ARTICLE | doi:10.20944/preprints202203.0271.v1
Subject: Engineering, Energy And Fuel Technology Keywords: equilibrium of mutual retention; self-contained energy of mutual retention; motor of mutual retention
Online: 19 March 2022 (03:25:32 CET)
This work proposes a new theoretical approach for the next generation of extremely efficient motors, whose impact will be substantial for future sustainable technological development. Building on well-known physical concepts, this approach introduces the concept of equilibrium of mutual retention, upon which a device remains in an equilibrium state between movement and attraction-repulsion. This new theoretical approach showed promising results in computer simulation experiments, indicating that the equilibrium of mutual retention can allow for a new way of modeling an extremely efficient motor. Finally, a theoretical efficiency analysis showed the need to expand the limits of some physical concepts already established.
ARTICLE | doi:10.20944/preprints201909.0007.v1
Subject: Business, Economics And Management, Business And Management Keywords: retention policy; emotional contribution; job retention and business growth
Online: 1 September 2019 (10:11:07 CEST)
This study investigates aspects of job retention and business growth in small- and medium-sized enterprises (SMEs). It examines how employers think about retention policy in relation to business growth, in contrast to previous studies’ main focus on employee motivation, job retention, and turnover. Qualitative semi-structured interviews were conducted face-to-face with Chief Executive Officers (CEOs) of Engineering and Informational Technology SMEs in South Korea. The results show that an important factor influencing job retention policies of SMEs is the motivation of employees to make voluntary effort, rather than offering them additional financial rewards or using other Human Resource Management (HRM) practices to improve individual performances. Interviewees believed that job retention and business growth are closely related and they discussed various ways of eliciting emotional contributions from employees. Unlike research on larger firms, these suggestions did not involve financial rewards. How employers think about the roles played by employees strongly influences their firm’s productivity and competitiveness. The SME CEOs examined in this study considered this issue central to their firm’s survival and growth. This study suggests SME employers adjust their retention policy correspondingly.
ARTICLE | doi:10.20944/preprints202212.0522.v1
Subject: Computer Science And Mathematics, Computer Networks And Communications Keywords: privacy; social media; data retention; hyperloglog
Online: 28 December 2022 (01:25:25 CET)
Social media data is widely used to gain insights about social incidents, whether on a local or global scale. Within the process of analyzing and evaluating the data, it is common practice to download and store it locally. Considerations about privacy protection of social media users are often neglected thereby. However, protecting privacy when dealing with personal data is demanded by laws and ethics. In this paper we introduce a method to store social media data using the cardinality estimator HyperLogLog. Based on an exemplary disaster management scenario, we show that social media data can be analyzed by counting occurrences of posts, without becoming in possession of the actual raw data. For social media data analyses like these, that are based on counting occurrences, cardinality estimation suffices the task. Thus, the risk of abuse, loss or public exposure of the data can be mitigated and privacy of social media users can be preserved. The ability to do unions and intersections on multiple data sets further encourages the use of this technology. We provide a proof-of-concept implementation for our introduced method, using data provided by the Twitter API.
ARTICLE | doi:10.20944/preprints201810.0055.v1
Subject: Social Sciences, Education Keywords: Native American students; Retention, Enrollment, Graduation
Online: 3 October 2018 (14:35:04 CEST)
Native Americans are the single most underrepresented racial group in American higher education today; those enrolled in college are also disproportionately first-generation students. In order to help universities attract and retain Native American students, this study utilizes the four R’s of indigenous research to document the motivations of first-generation Native American students to attend and remain at a mid-sized public university in the northwest. Student participants report that social and cultural support were key factors in their decisions to attend and remain at their institution. Implications of these findings are discussed, and recommendations are made to higher education institutions seeking to attract and retain Native American students.
ARTICLE | doi:10.20944/preprints202310.1762.v1
Subject: Engineering, Mechanical Engineering Keywords: lateral screw retained; retrievability; retention; dental implants
Online: 27 October 2023 (08:22:07 CEST)
This study aims to develop a novel retention method combining the retrievability of the screw retention method with the ideal occlusal table and the aesthetics capability of cement retention. Coping was developed to have lateral screw access allowing the screw to lock coping using lateral forces from screw tightening and friction between the tip of the screw and the sandblasted surface of an abutment. Sandblasting parameters varied based on particle size. Results show a positive correlation to surface roughness and indicate a positive correlation to retention force. The highest surface roughness and retention force result was shown by groups that were sandblasted using 686 μm of aluminum oxide. Experiment on the tightening strength of 48 subjects measured in simulated conditions similar to assembly conditions of lateral screw retention implant resulted in a mean of 69.75 Nmm with the highest and lowest values of 120.67 Nmm and 34.67 Nmm. This result became the basis of tightening torque variation. Each group's retention capability is measured and compared to cement-retained dental implants. Results show that tightening torque correlates positively with retention force, with the highest average retention score showed by lateral screw retained under tightening torque of 200 Nmm with 317.87 N higher than cement-retained.
ARTICLE | doi:10.20944/preprints202308.2025.v1
Subject: Biology And Life Sciences, Life Sciences Keywords: intron retention; RNA-seq; cancer; diagnosis; prognosis
Online: 30 August 2023 (14:10:03 CEST)
Alternative splicing can produce transcripts that affect cancer development and shows potential for cancer diagnosis and treatment. However, intron retention (IR), a type of alternative splicing, has been less systematically studied in cancer biology research. Here, we generated a pan-cancer IR landscape for more than 10,000 samples across 33 cancer types from The Cancer Genome Atlas (TCGA). We characterized differentially retained introns between tumor and normal samples and identified retained introns associated with survival. We discovered 988 differentially retained introns in 14 cancers, some of which demonstrated diagnostic potential in multiple cancer types. We also inferred a large number of prognosis-related introns in 33 cancer types, and the associated genes included well-known cancer hallmarks such as angiogenesis, metastasis, and DNA mutations. Notably, we discovered a novel intron retention event inside 5′UTR of STN1 that is associated with the survival of lung cancer patients. The retained intron reduces translation efficiency by producing upstream open reading frames (uORFs) and thereby inhibits colony formation and cell migration of lung cancer cells. Besides, the IR-based prognostic model achieved good stratification on certain cancers, as illustrated in acute myeloid leukemia. Taken together, we performed a comprehensive IR survey at a pan-cancer level, and the results implied that IR has the potential to be diagnostic and prognostic cancer biomarkers, as well as new drug targets.
REVIEW | doi:10.20944/preprints202307.1955.v1
Subject: Medicine And Pharmacology, Other Keywords: medical education; gamified learning; knowledge retention; algorithm
Online: 28 July 2023 (09:22:22 CEST)
The aim of this review was to summarize the available literature regarding resident and medical student education utilizing the spaced repetition program Anki. This review enables current residents and medical students to recognize and utilize evidence-proven study techniques to increase learning efficacy. A systemic review of papers across all medical journals available on Pubmed was conducted to identify studies published without time constraints. The search was for (Anki) and (spaced repetition residency). Available outcome data was collected and discussed independently for students and residents. Many studies showed a statistically significant increase in exam performance associated with Anki use and high levels of satisfaction among residents and medical students. Further research is warranted to provide high-quality evidence of Anki’s applications and there is a need for exploration in additional residency specialties. Anki use has steadily increased with both medical students and residents. The application demonstrated consistent improvement on exam-based performance and was regarded highly by users. As burnout and time constrictions threaten educational workflow, Anki may serve as a powerful tool to improve the quality of learning. Further data needs to be collected and analyzed in specialties where Anki use may already exist.
ARTICLE | doi:10.20944/preprints201811.0205.v1
Subject: Social Sciences, Education Keywords: cognates; kindergarten children; recall; recognition; vocabulary retention
Online: 8 November 2018 (10:49:05 CET)
This study investigates five-year-old learners’ vocabulary retention through case studies, on a one week, one month, three months, and five months basis. It concerns the vocabulary learning of kindergarten children learning English as a second language (L2). This study attempts to seek answers to the questions of to what extent the presentation of the three different sets of words more effective than the other two is, both on recall and recognition and whether the recall and recognition levels showed differences in the three sets of words in course of time. In the literature, some studies have favoured semantic mapping in which new words are presented and organized in terms of associated lexical meanings. Some other studies have disfavoured semantic mapping. This study has administered three different sets of vocabulary: semantically related, cognates and semantically unrelated words. This study indicated that all participants were more successful with semantically related words on word recall and with cognates on word recognition. The results of this study do not support those which claim that making semantic associations may cause interference and hinder vocabulary learning. This study further suggests that semantically related words should be taught thematically to facilitate vocabulary teaching, particularly on word recall.
ARTICLE | doi:10.20944/preprints201810.0680.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: desensitizing paste; dentin; retention; cements; cobalt-chromium
Online: 29 October 2018 (11:50:02 CET)
The effect of dentin pretreatment with desensitizing paste containing 8% arginine and calcium carbonate on the retention of laser-sintered cobalt-chromium (Co-Cr)-based crowns was examined. Forty molars were prepared using a standardized protocol. The Co-Cr crowns were produced using selective laser melting. The teeth were either pretreated with the desensitizing paste or not pretreated. After one week, each group was cemented with glass ionomer cement (GIC) or zinc phosphate cement (ZPC). Surface areas of the teeth were measured before cementation. After aging, the cemented crown-tooth assemblies were tested for retentive strength using a universal testing machine. The debonded surfaces of the teeth and crowns were examined at 2.7× magnification. Pretreating the dentin surfaces with the desensitizing paste before cementation with GIC or ZPC did not affect the retention of the Co-Cr crowns. The retention of the GIC group (6.04±1.10 MPa) was significantly higher than that of the ZPC group (2.75±1.25 MPa). The predominant failure mode for the ZPC and for the nontreated group of the GIC was adhesive cement-dentin; for the GIC-treated group, it was adhesive cement-crown. The desensitizing paste can be safely used to reduce postcementation sensitivity without reducing the retentive strength of Co-Cr crowns cemented with GIC or ZPC.
ARTICLE | doi:10.20944/preprints202312.0076.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: removable prosthesis; prosthesis modification; aesthetics, retention
Online: 4 December 2023 (08:36:13 CET)
The removable partial denture, despite new technologies and new materials, continues to play a significant role in clinical dental practice. The purpose of the following study was to evaluate the design of new retention devices in Kennedy's second grade classrooms. For the study of "lamellar" retentive devices, 4 prosthetists were chosen and selected, according to inclusion and exclusion criteria, 16 patients, 8 women and 8 men, whose upper arch had to be rehabilitated with a removable partial prosthesis. The results showed that the parameters taken into consideration such as satisfaction, stability, aesthetics and retention had an average score higher than 3.30 (range 1-4), with an average standard deviation of 0.6225 in the 4 indicative parameters that the data they are relatively homogeneous and coherent. In conclusion we can state that the skeletonized prosthesis with lamellar retentions, designed in Kennedy's second grade classes, has shown good acceptance in selected patients
ARTICLE | doi:10.20944/preprints202308.0259.v1
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: retention mechanism; partitioning; adsorption; phase ratio; quantitative; HILIC
Online: 3 August 2023 (05:19:09 CEST)
Retention mechanisms in HILIC have been investigated and reported in literature. However, the current understanding of the retention mechanisms is qualitative and lacks quantitative details. Previously, mechanism elucidation was based on indirect evidence, and unambiguous assignment of retention mechanisms has not been reported based on direct data. This study aims to quantitatively determine the contributions of two major retention mechanisms in HILIC, hydrophilic partitioning and surface adsorption to the overall retention of neutral compounds. Using the methodologies we developed previously, the phase ratio for adsorbed water layer and distribution coefficients were measured and used to calculate the retention factors attributed to hydrophilic partitioning. The methodology allows the determination of the contribution of surface adsorption simultaneously. The evaluation of five test compounds demonstrates that the retention may be controlled by hydrophilic partitioning, surface adsorption or both depending on compound characteristics. Quantitative assessment of retention mechanisms also makes it possible to better understand the effect of acetonitrile on retention in HILIC.
ARTICLE | doi:10.20944/preprints202106.0126.v1
Subject: Business, Economics And Management, Accounting And Taxation Keywords: municipality; profession; school leaders; retention and working conditions
Online: 4 June 2021 (08:23:20 CEST)
This article reports on the findings of a research project examining how to create a profession that is attractive and fulfilling for new and existing school leaders in two different municipalities in Sweden. The project set out to explore how work environments, career structures, salaries, and working conditions can contribute to attracting, retaining, and motivating school leaders to stay longer in the profession. To realise this objective, the study adopted a qualitative research design. Data was collected by carrying out semi-structured interviews with a sample of five school leaders in two different municipalities to investigate their experiences and views of the profession. The findings demonstrate that school leaders’ working conditions play a more critical role in their decisions to stay or leave the profession than financial compensation. The study also shows an unequal allocation of resources, both in terms of support functions and the limited time available for in-service education.
ARTICLE | doi:10.20944/preprints201805.0202.v1
Subject: Engineering, Civil Engineering Keywords: urban flood; hydrologic and hydraulic modeling; retention structures
Online: 15 May 2018 (06:03:58 CEST)
Flooding and overflows are recurring problems in several Brazilian cities, which usually undergo disorderly development. Their causes vary from increased impervious surface areas, deficiency/inefficiency of drainage structures and their maintenance, siltation of rivers, channel obstructions, and climatic factors. This situation is aggravated in the major cities. The Anhangabau watershed lies in the central portion of the city of Sao Paulo – Brazil and covers a drainage area of 5.4 km². The region is highly urbanized and crossed by a major north-south road connection. During heavy rain events, portions of this interconnection passage become compromised, disrupting the flow of vehicles, creating a chaotic situation for the population, as well as losses to the national economy. Observed rainfall records and an existing IDF (intensity duration frequency) curve for the region are used to obtain design storms. To account for climate change, a well know procedure, the equidistance quantile matching method for updating IDF curves under climate change, was applied to the existing historical data. Several different global climate models (GCM) and one regional model were applied to obtain and update rainfall design storm. The GCMs and future scenarios used were from the IPCC Assessment Report 5 (AR5) and two future projections: RCP (representative concentration pathway) 4.5 and 8.5. Alternatives previously proposed to solve to flooding issue are briefly reviewed. On one of the latest studies , a few modern concepts of water resources management are presented, and the linear retention measure was found to offer higher potential to mitigate the flooding problem in the lower valley of the watershed. Therefore, this alternative was used to evaluate different design storms scenarios combined with return periods of 25 and 100-years as well as the updated IDF under climate change for RCP 4.5 and RCP 8.5. To model the complex network, representing both road and drainage systems and their interconnections, PCSWMM/SWMM software was applied. Results are presented as flooding maps and show the impacts of the proposed linear retention measure based on the existing IDF curves and the updated IDF curves under climate change for two different drainage system conditions, current and improved with the use of linear retention reservoirs. Results show that the prosed changes on the drainage system help reduce the risk and damage to flooding. The climate change scenarios, however, impose a significant threat and need immediate attention from city planners and stakeholders.
ARTICLE | doi:10.20944/preprints202310.1249.v1
Subject: Social Sciences, Psychology Keywords: jealousy; partner retention strategies; romantic relationship; age; relationship length
Online: 20 October 2023 (08:06:42 CEST)
Jealousy and mate retention have received attention in the research over the last decades. Despite this, most of the research examined male jealousy and male mate retention, emphasizing cost-inflicting behavior due to its role in relationship and domestic violence. The aim of this study was to investigate the relationship between jealousy and all mate retention strategies in romantic relationship among women during the COVID-19 pandemic. The sample consisted of 772 Croatian women aged 19 to 40 who were in a heterosexual relationship at the time. The study was conducted online, and the participants completed the Multidimensional jealousy scale and Mate Retention Inventory. The results showed that cognitive, emotional, and behavioral jealousy are positively correlated with all mate retention strategies which indicate that a stronger experience of jealousy can be expected to result in more frequent use of all partner retention strategies. We also found that all three dimensions of jealousy and relationship length positively predicted both cost-inflicting and benefit-provisioning mate retention behavior, whereas age was a negative predictor of benefit-provisioning behavior only. Findings of this study suggest that although jealousy can substantially explain interpersonally risky and damaging behavior in relationships, it can also explain affectionate and attentive behavior to some extent.
ARTICLE | doi:10.20944/preprints202107.0061.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: Sheep breeds; Awassi; Najdi; Harri; Growing; Digestibility; Nitrogen retention
Online: 2 July 2021 (14:19:29 CEST)
Forty-five of intact three sheep breeds (Awassi, Harri, and Najdi) were used in this study (15 animals of each breed), with weight ranged from 23.40 to 25.87 kg. Five animals from each group at the end of growth trial were used for digestibility and nitrogen balance trials. The three groups of sheep had effect (p > 0.05) in the final live weight (FLW). Average daily feed intake (ADI), average daily gain (ADG) and feed conversion ratio (FCR) were significantly (p < 0.05) different among the three groups. For digestibility coefficients, the three breeds of sheep had no effect (p > 0.05) in dry matter (DM), organic matter (OM), crude protein (CP), crude fiber (CF), nitrogen free extract (NFE), neutral detergent fiber (NDF) and acid detergent fiber (ADF). In the similar approach, no significant differences were founds among three breeds of sheep in digestible organic matter, digestible of crude protein, total digestible nutrients and nitrogen retention. The current study concluded that the sheep breeds affected average daily feed intake, average daily gain and feed conversion ratio (FCR). Awassi breed showed the best of average daily gain and feed conversion ratio followed by Najdi then Harri breeds. The breed of sheep had no effect on digestibility coefficients and nitrogen retention.
Subject: Biology And Life Sciences, Ecology, Evolution, Behavior And Systematics Keywords: Biodiversity; Conservation; Extinction; Threat management; Habitat retention; Protected Areas.
Online: 19 October 2020 (11:08:56 CEST)
Earth’s extinction crisis is escalating, and threat classification schemes are increasingly important for assessing which human activities are the most prominent drivers of species declines. However, a quantitative understanding of the conservation responses needed to abate threatening processes, and avoid species extinctions, is often lacking. Here, we provide a threat abatement framework which groups threats based on the shared conservation goal of the actions needed to abate their impact. We apply this framework to Australia’s threatened species to quantify the relative importance of achieving different conservation response goals. Our analysis shows the most important conservation responses across Australia are habitat retention and restoration, due to the combined impact of threatening processes causing habitat destruction and degradation (e.g. logging, mining, urbanisation and agriculture), which affects the majority (86%) of Australia’s threatened species and the effective control of invasive species (82%). Most species also require conservation responses focussed on improved fire management (66%). We show that implementing responses in isolation will be inadequate for abating species extinctions as almost all species (89%) require multiple, integrated management responses to redress their threats. We also acknowledge that already small and potentially genetically compromised taxa may require more direct interventions (e.g. captive insurance populations or genetic rescue). Our analysis highlights the necessity of addressing multiple threats at appropriate geographic scales across Australia. Our threat abatement framework ensures that core conservation actions can be identified and aid recovery of threatened species, and can be applied to other geographic regions and conservation contexts.
ARTICLE | doi:10.20944/preprints201911.0362.v1
Subject: Business, Economics And Management, Human Resources And Organizations Keywords: employee retention; employee turnover; client embeddedness; human resource management
Online: 28 November 2019 (11:22:28 CET)
The employee turnover literature to date is teeming with process models that assume only organizational and personal factors contribute to employees’ intentions to leave and stay. However, with the average percentage variance explained still only around 50%, it is clear that other factors play a substantial role in these decision-making processes. One possible explanation is to explore the unique role that clients play in employees’ intentions to stay or leave. This paper extends the conceptualization of the role that clients play on employee’s intentions to stay and leave their roles, particularly within service industries such as health care. This paper presents the results of two qualitative studies that examine employees’ decision-making process for turnover and retention intentions. The first study explores the factors influencing employees’ intentions to stay and leave the Australian aged care sector (N = 420) and the second study explores prison health care nurses in the United States (N = 175). The results of both studies reveal that client-related factors affect the choice to stay within a job and, in some cases, are the favoured aspect of the role. Therefore encouraging client-staff relationships will expand job satisfaction and therefore increase retention of employees within both contexts.
ARTICLE | doi:10.20944/preprints201806.0500.v1
Subject: Chemistry And Materials Science, Nanotechnology Keywords: nanocellulose; retention; petroleum; energy; oil; petrochemical; cellulose nanocrystals; nanoparticle
Online: 30 June 2018 (15:15:54 CEST)
The application of nanotechnology to the petroleum industry has sparked recent interest to increase oil recovery while reducing environmental impact. Nanocellulose is an emerging nanoparticle that is derived from trees and may provide an environmentally friendly alternative to current enhanced oil recovery (EOR) technologies. However, before nanocellulose can be applied as an EOR technique, further understanding of its transport behavior and retention in porous media is required. The research documented in this paper examines retention mechanisms that occur during nanocellulose transport. In a series of experiments, nanocellulose particles dispersed in brine were injected into sandpacks and Berea sandstone cores. The resulting retention and permeability reduction were measured. The experimental parameters that were varied include sand grain size, nanocellulose type, salinity, and flow rate. Under low salinity conditions, the dominant retention mechanism was adsorption and when salinity was increased, the dominant retention mechanism shifted towards log-jamming. Retention and permeability reduction increased as grain size decreased, which results from increased straining of nanocellulose aggregates. In addition, each type of nanocellulose was found to have significantly different transport properties. The experiments with Berea sandstone cores indicate that some pore volume was inaccessible to the nanocellulose. As a general trend, the larger the size of aggregates in bulk solution, the greater the observed retention and permeability reduction. Salinity was found to be the most important parameter affecting transport. Increased salinity caused additional aggregation, which led to increased straining and filter cake formation. Higher flow rates were found to reduce retention and permeability reduction. Increased velocity was accompanied by an increase in shear which is believed to promote breakdown of nanocellulose aggregates.
ARTICLE | doi:10.20944/preprints201806.0237.v1
Subject: Biology And Life Sciences, Agricultural Science And Agronomy Keywords: biochar; compost; nutrient retention; highly weathered soil; Chinese cabbage
Online: 14 June 2018 (15:46:36 CEST)
Highly weathered soils in the tropics are low in fertility, negatively affecting plant growth. The potential of biochar for improving soil nutrient retention is reportedly promising, triggering this study to assess the nutrient retention capacities of two biochars when applied at 2% in combination with two composts also applied at 2% to an Ultisol (Ustic Kanhaplohumult, Leilehua series) and an Oxisol (Rhodic haplustox, Wahiawa series) of Hawai’i. Chinese cabbage (Brassica rapa cv. Bonsai) was used as the test plant in two greenhouse plantings, which had a factorial completely randomized design with three replicates per treatment. The results indicated that the combined additions of biochar and compost significantly increased the pH, EC, P and K of the soils; improved Ca, Mg and Fe uptake; and increased shoot and total cabbage fresh and dry matter. Exchangeable aluminum in the Ultisol was decreased from 2.5 cmol+/kg to virtually zero. Extractable Mn and Fe in the high Mn-Oxisol were decreased by 55 and 42%, respectively. Chinese cabbage growth in the Ultisol amended with the lac tree (Schleichera oleosa) wood biochar and vermicompost was almost twice over lime at 2 cmol+/kg. Essential nutrients in the plant tissues, with the exception of N and K, were sufficient for the cabbage growth, suggesting increases in nutrients and reduced soil acidity by the additions of biochar combined with compost were the probable cause.
ARTICLE | doi:10.20944/preprints201806.0037.v1
Subject: Engineering, Control And Systems Engineering Keywords: green roof; water retention efficiency; runoff quality; hydrological performance
Online: 4 June 2018 (11:56:40 CEST)
This study assessed the hydrological performance and runoff water quality of 12 green roof (GR) modular systems located at the Universidad de los Andes campus (Bogotá, Colombia). Based on 223 rainfall events spanning a 3-year period, average rainfall retention was 85% (SD = 25%). T-tests, Welch Test, multiple linear regressions and correlation analysis were performed in order to assess the potential effect of air temperature, substrate type, vegetation cover, relative humidity, antecedent dry weather period (ADWP), rainfall duration and rainfall maximum intensity. In some cases, GR design variables (i.e. growing media and type of vegetation) were found to be significant for describing rainfall retention efficiencies and, depending on the GR type, some hydrological variables were also correlated with the rainfall retention. Rainfall and GR runoff were monitored for Total Kjeldahl Nitrogen (TKN), Nitrates, Nitrites, Ammonia, Total Phosphorus (TP), Phosphates, pH, Total Dissolved Solids (TDS), Total Suspended Solids (TSS), Color, Turbidity, Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Coliforms, metals and Poliaromatic Hydrocarbons (PAHs). The results obtained confirmed that GR systems have the ability to neutralize pH, but are source of the rest of the aforementioned parameters, excluding PAHs (with concentrations below detection limits), Ammonia, TSS, Se and Li, where differences with reference values (rainfall and plastic panel runoff) were not statistically significant. Substrate type, event size and rainfall regime are relevant variables for explaining runoff water quality.
ARTICLE | doi:10.20944/preprints202209.0138.v1
Subject: Chemistry And Materials Science, Inorganic And Nuclear Chemistry Keywords: radionuclide; uranyl; retention; cementitious media; saline plume; NaNO3; luminescence; TRLFS
Online: 9 September 2022 (13:31:00 CEST)
Evaluation of the mobility behavior of radionuclides in highly saline and alkaline conditions is a major concern for performance assessment of radioactive waste disposal. The aim of this study is to determine the effect of up to 2.8 mol/kgsolution content of NaNO3, onto the solubility and the sorption of U(VI) in a hardened cement-paste (HCP) prepared from an ordinary Portland cement (CEM I). To avoid the interference of the high salt concentration (and ionic strength) and because of expected low solubility of uranium under such alkaline conditions, the time-resolved laser fluorescence (TRLFS) was selected to measured accurate U(VI) concentration in solution using the standard addition method in 85% H3PO4 to limit dilution and matrix effects and allows determining of resulting [U(VI)] in solution with acceptable precision for distribution factor (Rd) both in sorption and desorption experiments. The operational solubility limit measured at high ionic strength is lowered by a factor 3 compared to the reference cementitious condition, with the Rd values decrease by ca. a factor 4. Sorption of U(VI) appears to be reversible under these conditions.
ARTICLE | doi:10.20944/preprints202103.0603.v1
Subject: Environmental And Earth Sciences, Atmospheric Science And Meteorology Keywords: Ecosystem Services; Spatial Modelling; Soil Erosion; Sediment retention; InVEST model
Online: 24 March 2021 (16:22:25 CET)
Soils provide important regulating ecosystem services and have crucial implications for human well-being and environmental conservation. However, soil degradation and particularly soil erosion jeopardize the maintenance and existence of these services. This study explores the spatio-temporal relationships of soil erosion to understand the distribution patterns of sediment retention services in mainland Portugal. Based on Corine Land Cover maps from 1990 to 2018, the InVEST Sediment Delivery Ratio (SDR) model was used to evaluate the influence of sediment dynamics for soil and water conservation. Spatial differences in the sediment retention levels were observed within the NUTS III boundaries, showing which areas are more vulnerable to soil erosion processes. Results indicated that the Region of Leiria, Douro and the coastal regions have decreased importantly sediment retention capacity over the years. However, in most of the territory (77.52%) changes in sediment retention were little or not important (i.e., less than 5%). The statistical validation of the model proved the consistency of the results, highlighting the usefulness of this methodology to analyse the state of soil erosion in the country. These findings can be relevant to support strategies for more efficient land use planning regarding soil erosion mitigation practices.
REVIEW | doi:10.20944/preprints202010.0243.v1
Subject: Business, Economics And Management, Accounting And Taxation Keywords: distance education; open and distance education; student retention; survival analysis
Online: 12 October 2020 (13:22:55 CEST)
Student retention is one indicator of accountability in the implementation of educational programs. Achievement of student retention rates indicates the performance of the quality objectives of an institution or college. To get an accurate picture of the factors related to retention, we need to do modeling. The retention variable is the time response variable measured in semester units. One of the statistical analyzes that can be used to analyze response data in time is survival analysis. The selection of an accurate analytical method in modeling will produce valid conclusions and impact making policies that are right and on target. This paper presents alternative modeling of student retention in distance education using survival analysis. The method used is a literature review. This paper also briefly describes distance education, open and distance education, distance education students' characteristics, distance education student retention, and survival models for modeling student retention in distance education.
REVIEW | doi:10.20944/preprints202005.0314.v1
Subject: Biology And Life Sciences, Virology Keywords: antiretroviral therapy; differentiated service delivery; retention; suppression; Africa; systematic review
Online: 19 May 2020 (09:53:46 CEST)
Introduction: Differentiated service delivery (DSD) models for antiretroviral treatment (ART) for HIV are being scaled up in the expectation that they will improve the quality and efficiency of treatment delivery and reduce costs while maintaining at least equivalent clinical outcomes. Even this minimum requirement of equivalent clinical outcomes is poorly documented for most models and settings, however. We reviewed the recent literature on DSD models to describe what is known about clinical outcomes. Methods: We conducted a rapid systematic review of peer-reviewed publications in PubMed, Embase, and the Web of Science and major international conference abstracts that reported outcomes of DSD models for the provision of ART in sub-Saharan Africa from January 1, 2016 to September 12, 2019. Sources reporting standard clinical HIV treatment metrics, primarily retention in care and viral load suppression, were reviewed and categorized by DSD model and source quality assessed. Results and Discussion: Twenty-nine papers and abstracts describing 37 DSD models and reporting 52 discrete outcomes met search inclusion criteria. Of the 37 models, 7 (19%) were facility-based individual models, 12 (32%) out-of-facility based individual models, 5 (14%) client-led groups, and 13 (35%) healthcare worker-led groups. Retention was reported for 73% of the models and viral suppression for 57%. Where a comparison with conventional care was provided, retention in most DSD models was within 5% of that for conventional care; where no comparison was provided, retention generally exceeded 80%. For viral suppression, all those with a comparison to conventional care reported a small increase in suppression in the DSD model; reported suppression exceeded 90% in 11/21 models. Analysis was limited by the extensive heterogeneity of study designs, outcomes, models, and populations. Most sources did not provide comparisons with conventional care, and metrics for assessing outcomes varied widely and were in many cases poorly defined. Conclusion: Existing evidence on the clinical outcomes of DSD models for HIV treatment in sub-Saharan Africa is limited in both quantity and quality but suggests that retention in care and viral suppression are roughly equivalent to those in conventional models of care.
REVIEW | doi:10.20944/preprints201902.0238.v1
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: hydride surface; silicon-carbon bond; aqueous normal phase; retention mechanism
Online: 26 February 2019 (11:33:15 CET)
The development of a stationary phase material for high performance liquid chromatography based on a surface of silica hydride as opposed to silanols on ordinary silica is discussed including synthetic approaches, characterization and applications. There are several synthetic approaches available to create a silica hydride surface. Modification of the Si-H moiety on the silica surface can be accomplished through use of a hydrosilation reaction. Both the intermediate silica hydride and the material modified with an organic moiety can be characterized by a number of spectroscopic as well as a variety of other methods. Further insights into the retention mechanism are provide through chromatographic measurements. The ultimate utility of any chromatographic stationary phase material is determined by its success for solving challenging analytical problems. A broad range of applications are reviewed to illustrate the versatility and usefulness of silica hydride-based stationary phases.
HYPOTHESIS | doi:10.20944/preprints201702.0018.v1
Subject: Social Sciences, Education Keywords: mastery learning strategy; learning retention; achievement; physical geography; conventional method
Online: 5 February 2017 (10:01:59 CET)
The need to alleviate the difficulties of abstraction and improve students’ achievement in Physical Geography informed this research. This study investigated the Effects of Mastery Learning Strategy and Learning Retention on Senior Secondary School Students’ Achievement in Physical Geography. The study adopted the quasi experimental non-equivalent pre-test, post-test control group design. The Multi-stage sampling technique at four levels was used to select four co-educational secondary schools in Ganye Educational Zone in Nigeria. The sample for the study was 218 Senior Secondary School two (SS II) students offering Geography from four intact classes in the four selected secondary schools. The instrument used for data collection was “Physical Geography Achievement and Retention Test” (PGART). The reliability of the instrument was established using Kendall tau b statistic. This gave a reliability index of 0.74. Data collected were analyzed using Mann-Whitney U and t-Test. The results showed that Mastery Learning Strategy has the potentials to improve students’ learning outcomes, retention and achievement in all spheres of cognitive domain in Physical Geography better than the Conventional Method. Hence the need to incorporate this teaching strategy during instruction so that learners would be guided to learn meaningfully and be assisted to retain content learnt in Geography.
ARTICLE | doi:10.20944/preprints202002.0425.v1
Subject: Environmental And Earth Sciences, Environmental Science Keywords: hydraulic conductivity; pedotransfer function; prediction uncertainty; random forest; soil water retention
Online: 28 February 2020 (12:06:14 CET)
Soil hydraulic properties are often derived indirectly, i.e. computed from easily available soil properties with pedotransfer functions (PTFs), when those are needed for catchment, regional or continental scale applications. When predicted soil hydraulic parameters are used for the modelling of the state and flux of water in soils, uncertainty of the computed values can provide more detailed information when drawing conclusions. The aim of this study was to update the previously published European PTFs (Tóth et al., 2015, euptf v1.4.0) by providing prediction uncertainty calculation built into the transfer functions. The new set of algorithms was derived for point predictions of soil water content at saturation (0 cm matric potential head), field capacity (both -100 and -330 cm matric potential head), wilting point (-15.000 cm matric potential head), plant available water, and saturated hydraulic conductivity, as well as the Mualem-van Genuchten model parameters of the moisture retention and hydraulic conductivity curve. The minimum set of input properties for the prediction is soil depth and sand, silt and clay content. The effect of including additional information like soil organic carbon content, bulk density, calcium carbonate content, pH and cation exchange capacity were extensively analysed. The PTFs were derived adopting the random forest method. The advantage of the new PTFs is that they i) provide information about prediction uncertainty, ii) are significantly more accurate than the euptfv1, iii) can be applied for more predictor variable combinations than the euptfv1, 32 instead of 5, and iv) are now also derived for the prediction of water content at -100 cm matric potential head and plant available water content.
ARTICLE | doi:10.20944/preprints201805.0070.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: Hyperpolarized gas MRI; xenon; gas retention; Alzheimer’s disease; wash out; vascular
Online: 3 May 2018 (12:02:44 CEST)
Biomarkers have the potential to aid in the study of Alzheimer’s disease (AD); unfortunately, AD biomarker values often have a high degree of overlap between healthy and AD individuals. This study investigates the potential utility of a series of novel AD biomarkers, the sixty second 129Xe retention time, and the xenon washout parameter, based on the washout of hyperpolarized 129Xe from the brain of AD participants following inhalation. The xenon washout parameter is influenced by cerebral perfusion, T1 relaxation of xenon, and the xenon partition coefficient, all factors influenced by AD. Participants with Alzheimer’s disease (n=4) and healthy volunteers (n=4) were imaged using hyperpolarized 129Xe magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) to determine the amount of retain xenon in the brain. At 60 sec post breath hold, AD patients retained significantly higher amounts of 129Xe compared to healthy controls. Data was fit to a pharmacokinetic model and the xenon washout parameter was extracted. Xenon washout in white and grey matter occurs at a slower rate in Alzheimer’s participants (129Xe half-life time of 42s and 43s, respectively) relative to controls (20s and 16s, respectively). Following larger scale clinical trials for validation, the xenon washout parameter has the potential to become a useful biomarker for the support of an AD diagnosis.
ARTICLE | doi:10.20944/preprints202310.0006.v1
Subject: Biology And Life Sciences, Plant Sciences Keywords: Abies balsamea; cold; conifer; fluorescence; galactosyldiacylglycerol; galactolipids; phospholipids; membrane injury; needle retention
Online: 1 October 2023 (08:11:54 CEST)
Needle abscission in balsam fir has been linked to both cold acclimation and changes in lipid composition. The overall objective of this research is to uncover lipid changes in balsam fir during cold acclimation and link those changes with postharvest abscission. Branches were collected monthly from September to December and assessed for cold tolerance via membrane leakage and chlorophyll fluorescence changes at -5, -15, -25, -35, and -45°C. Lipids were extracted and analyzed using mass spectrometry while postharvest needle abscission was determined gravimetrically. Cold tolerance and needle retention each significantly (P < 0.001) improved throughout autumn in balsam fir. There were concurrent increases in DGDG, PC, PG, PE, and PA throughout autumn and a decrease in MGDG. Those same lipids were strongly related to cold tolerance, though MGDG had the strongest relationship (R2 = 55.0% and 42.7% from membrane injury and chlorophyll fluorescence, respectively). There was a similar, albeit weaker, relationship between MGDG:DGDG and needle retention (R2 = 24.3%). Generally, a decrease in MGDG:DGDG ratio resulted in better cold tolerance and higher needle retention in balsam fir possibly due to increased membrane stability.
ARTICLE | doi:10.20944/preprints202309.0289.v1
Subject: Environmental And Earth Sciences, Remote Sensing Keywords: soil moisture; remote sensing; SMAP; Sentinel-1; soil-water retention curve; validation; Thailand
Online: 6 September 2023 (03:46:43 CEST)
Soil moisture plays a crucial role in various hydrological processes and energy partitioning of the global surface. The Soil Moisture Active Passive-Sentinel (SMAP-Sentinel) remote sensing technology has demonstrated a great potential in monitoring soil moisture at a scale greater than 1 km. This capability can be applied to improve weather forecast accuracy, enhance water management for agriculture, and climate-related disasters. Despite the techniques increasing used worldwide, its accuracy still requires field validation in specific regions like Thailand. In this paper, we report on extensive in-situ monitoring of soil moisture (from surface up to 1 m depth) at 10 stations across Thailand spanning the years 2021 to 2023. The aim was to validate SMAP surface soil moisture (SSM) Level 2 product over a period of two years. Using one month averaging approach, the study revealed linear relationships between the two measurement types, with the coefficient of determination (R-squared) varying from 0.13 to 0.58. Notably, areas with more uniform land use and topography such as croplands tended to have a better coefficient of determination. We also conducted detailed soil core characterization, including soil-water retention curves, permeability, porosity, and other physics properties. These soil properties were then used for estimating the correlation constants between SMAP and in-situ soil moistures using multiple linear regression. The results demonstrated R-squared values between 0.933 and 0.847. An upscaling approach of SMAP was proposed which showed a promising results when using 3-month average of all measurements in cropland together. The finding also suggest that the SMAP-Sentinel remote sensing technology exhibits significant potential for accurate soil moisture monitoring in diverse applications. Further validation efforts and research, particularly in terms of root zone depths and area-based assessments, especially in the agricultural sector, can greatly improve the technology’s effectiveness and usefulness in the region.
ARTICLE | doi:10.20944/preprints202307.1345.v1
Subject: Business, Economics And Management, Marketing Keywords: quality of experience; brand trust; brand attachment; user retention intention; case study; fsQCA
Online: 20 July 2023 (02:36:47 CEST)
To achieve user retention through multifactor synergy, Internet enterprises must reduce costs and increase efficiency and sustainable development. In response to the dilemma that Internet compa-nies are experiencing increasingly high user acquisition costs and serious user churn, this paper uses a sample of 46,695 user reviews of nine product series from Xiaomi Ecological Chain. Case studies and qualitative comparative analysis are used to explore the influence mechanisms of quality of experience, brand trust, and brand attachment on users' retention intentions. Our find-ings are as follows. (1) Brand attachment alone is not necessary for high user retention intention, but user perception, cognition, and brand trust are necessary. (2) Quality of experience positively impacts brand trust, attachment, and user retention intention. Therefore, improving user perception and cognition is critical in generating high user retention intention. (3) Five configuration paths can achieve high user retention intention, three configuration paths lead to low user retention intention, and there is an asymmetric relationship between these paths. Among them, the role of quality of experience-driven configuration paths in generating user retention intention is the most prominent. (4) In the substitution relationship between configuration paths, user perception, and cognition can substitute with brand trust and attachment. Our findings have important theoretical and practical implications for revealing the realization paths of high user retention intention in Internet companies and provide a new perspective for future research.
ARTICLE | doi:10.20944/preprints202306.0509.v1
Subject: Engineering, Energy And Fuel Technology Keywords: nanoparticles enhanced oil recovery; pH control; alumina nanoparticles; permeability damage; transportability and retention
Online: 7 June 2023 (08:12:40 CEST)
Enhanced oil recovery using nanoparticles is a promising method. However, when injected into a reservoir, nanoparticles can block pores and cause permeability damage. Therefore, enhancing their performance to lower the permeability damage effect is crucial. This study investigated the effect of pH alteration through carbon dioxide (CO2) injection on the permeability damage of limestone caused by the aluminum oxide (α-Al2O3) nanofluid. The methodology involved nanofluid alternating CO2 core flooding experiments by using nanofluids with pH of 4.5 and 2.8. After core flooding, permeability damage was calculated as a percentage of the reduction of the original permeability. The results revealed that the permeability damage in the case of nanofluid alternating CO2 injection was 23.23%. In only nanofluid with a pH of 4.5 injection case, permeability damage was 47.53%. In the 2.8 pH nanofluid injection case, permeability damage was 31.01%. The retention of nanoparticles was confirmed through scanning electron microscopy and energy dispersive X-ray analysis. Permeability damage could be attributed to a large nanoparticles’ agglomeration size, roughness of pore surfaces, and nanoparticle sedimentation. The results of the study revealed that altering pH through the α-Al2O3 nanofluid alternating CO2 injection can effectively reduce the permeability damage of limestone.
ARTICLE | doi:10.20944/preprints202304.0325.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: agarose; methyl substituent; DSC; NMR; water retention; rheology; gelation hysteresis; gel in ethanol
Online: 13 April 2023 (12:49:48 CEST)
Abstract: Agarose is known to form a homogeneous thermoreversible gel in aqueous medium over a critical polymer concentration. The solid-liquid phase transitions are thermoreversible but depend on the molecular structure of the agarose sample tested. Then, in a first step, the structure was characterised by 1H and 13C NMR in D2O and in DMSO which is a solvent of agarose whatever the temperature. A low yield in methyl substituent on the D-galactose unit was determined. Then, evolution of the 1H NMR spectrum was followed as a function of temperature in increasing and decreasing temperature process from 25 to 80°C. A large thermal hysteresis is obtained and discussed. It helps to interpret rheological behaviour. In fact, NMR signals are related to proton relaxation and especially to proton involved in H-bonds between water and -OH agarose for tightly bound water and agarose/agarose in chain packing. In a second step, water was exchanged against ethanol which is a non solvent of agarose. A stable gel was demonstrated and characterised by rheology to be compared with aqueous behaviour. Bound water playing the role of plasticizer is probably removed and the gel is much stronger (and brittle) in ethanol with a larger thermal stability. It is the first time that such gel is characterised without phase transition when passing from a good-solvent to a non-solvent. This extends the domains of application of agarose.
Subject: Environmental And Earth Sciences, Atmospheric Science And Meteorology Keywords: disaster management; virtual operation support teams; privacy; data retention; hyperloglog; focus group discussion
Online: 1 October 2020 (13:58:16 CEST)
Social media data is heavily used to analyze and evaluate situations in times of disasters, and derive decisions for action from it. A cruicial part of the analysis is to avoid unnecessary data retention during that process, in order to prevent subsequent abuse, theft or public exposure of collected datasets and thus, protect the privacy of social media users. There are a number of technical approaches out to face the problem. One of them is using a cardinality estimation algorithm called HyperLogLog to store data in a privacy-aware structure, that can not be used for purposes other than the originally intended. In this case study, we developed and conducted a focus group discussion with teams of social media analysts, in which we identified challenges and opportunities of working with such a privacy-enhanced social media data structure in place of conventional techniques. Our findings show that, with the exception of training scenarios, deploying HyperLogLog in the data acquisiton process will not distract the data analysis process. Instead, it will improve working with huge datasets due to the improved characteristics of the resulting data structure.
ARTICLE | doi:10.20944/preprints201809.0574.v1
Subject: Engineering, Chemical Engineering Keywords: hydrodynamic; gas retention; submerged membrane bioreactor; influence of temperature; oxygen mass transfer coefficient
Online: 29 September 2018 (03:53:05 CEST)
Gas-liquid reactors pose transfer difficulties due to diffusion effects. It is necessary to master the aeration and hydrodynamics of the medium to conduct the reaction well and get a good performance. For this purpose, a study in a submerged membrane bioreactor with a useful volume of 30L, consisting of a microfiltration membrane with an average pore size of 0.14 mm having an effective surface area of 0.2 m2 and a PVC cylindrical air diffuser of radius 4 cm has been studied. The saline tracing method associated with a conductimetric follow-up made it possible to determine the residence times and the mixing time in the reactor at 4 different points both in recirculation and in the absence of recirculation. Gas retention was measured by the manometric method. The experiments were carried out at different temperatures of 25 ° C, at 45 ° C, with a variable air flow rate of 0.5 to 16 mL / s and different solutions (osmosis water, ammonium formate solution, solution ammonium formate + salt, synthetic rubber effluent). The results show that the mixing time varies from one point to another and the recirculation of the mixture reduces the mixing time. One of the positions is limiting, the transfer is done most by diffusion with a mixing time of 115 min without circulation and 65 min with circulation. Gas retention increases with aeration rate and temperature. On the other hand, the more the medium becomes rich in organic substances, the more the gaseous retention decreases. The homogeneous fine-bubble regime is obtained for an air flow rate of between 3 and 10 mL / s of aeration. Beyond this flow rate, the regime becomes heterogeneous without a transition phase for ammonium formate and formate ammonium + salt solutions.
ARTICLE | doi:10.20944/preprints201806.0358.v1
Subject: Chemistry And Materials Science, Polymers And Plastics Keywords: biodestruction, soil constructions, sustainability, polymers, synthetic hydrogels, peat, CO2 emission, water-retention, modeling.
Online: 22 June 2018 (14:20:10 CEST)
Decomposition of natural and synthetic polymeric materials (peat, humates, biochar, strongly swelling hydrogels and other soil conditioners) in a biologically- and chemically- active soil environment inevitably leads to their degradation and ability to improve the structure, water-retention, absorptive capacity and actual fertility of artificial soil constructions in urbanized ecosystems and agro landscapes (constructozems). Quantitative assessment of the biodegradation process using field and laboratory incubation experiments, as well as mathematical modeling, showed the possibility of significant (up to 30-50% per year) losses of organic matter of constructozems and a corresponding deterioration in their quality. Incubation experiments with the analysis of carbon dioxide emission for polymeric materials under given thermodynamic conditions allow to estimate the potential rates of their decomposition (half-life) and their dependence on the dose of inhibitors of microbial activity. Special nomographs provide an opportunity to determine the optimum depth of the arrangement of organic components in soil constructions to ensure their stable functioning during a fixed operating time in urban conditions. The results of the study are useful for geo-engineers and landscaping practitioners.
ARTICLE | doi:10.20944/preprints202211.0037.v1
Subject: Social Sciences, Language And Linguistics Keywords: non-native speech learning; talker variability; phonetically-irrelevant variability; long-term retention; cognitive abilities
Online: 2 November 2022 (03:05:23 CET)
Talker variability has been reported to facilitate generalization and retention of speech learning, but is also shown to place demands on cognitive resources. Our recent study provided evidence that phonetically-irrelevant acoustic variability in single-talker (ST) speech is sufficient to induce equivalent amounts of learning to the use of multiple-talker (MT) training. This study is a follow-up contrasting MT versus ST training with varying degrees of temporal exaggeration to examine how cognitive measures of individual learners may influence the role of input variability in immediate learning and long-term retention. Native Chinese-speaking adults were trained on the English /i/-/ɪ/ contrast. We assessed the trainees’ working memory and selective attention before training. Trained participants showed retention of more native-like cue weighting in both perception and production regardless of talker variability condition. The ST training group showed long-term benefit in word identification, whereas the MT training group did not retain the improvement. The results demonstrate the role of phonetically-irrelevant variability in robust speech learning and modulatory functions of nonlinguistic working memory and selective attention, highlighting the necessity to consider the interaction between input characteristics, task difficulty, and individual differences in cognitive abilities in assessing learning outcomes.
ARTICLE | doi:10.20944/preprints201710.0036.v1
Subject: Business, Economics And Management, Business And Management Keywords: Organizational loyalty, human resource management practices, structural equation modeling, employee turnover and employee retention
Online: 6 October 2017 (10:00:34 CEST)
The role of human resource management practices and organizational loyalty dealing with employee retention has been widely explored and examined in the existing literature. The majority of human resource management researchers have focused on the role of policies and practices in different sectors related to employee retention. However, less attention has been given to identifying the practices and procedures common across all industries and sectors. The present study attempts to determine and examine the most important constructs like HR practices and organizational loyalty of employee retention management and proposes a comprehensive structural equation model to measure the impact of these constructs on employee retention. After an extensive review of the literature, organizational loyalty, and human resources management practices like recruitment and selection, compensation and benefit, training and development, supervision and evaluation have been identified as four essential practices dealing with employee retention and are common across all industries. These practices constitute the component factors of an employee retention management predicting employee’s turnover intentions. The survey method was adopted, and the original data obtained through the self-administered questionnaire. The valid one hundred and eighty-nine (189) respondents analyzed by using Lisrel 8.7, Structural equation model (SEM) analysis results shows that human resource management practices and organizational loyalty have strong positive impact on employee retention. This study tends to assist human resource managers and decision makers in selecting the appropriate motivating factors to retain and satisfy their employees
ARTICLE | doi:10.20944/preprints202307.0066.v1
Subject: Environmental And Earth Sciences, Environmental Science Keywords: Controlled agrochemical release; urea fertilizer; poly(vinyl alcohol; chitosan; gum Arabic; SAP hydrogel; water-retention
Online: 7 July 2023 (14:27:57 CEST)
Agriculture technical development exclusively relies on the effective delivery of agrochemicals and water to the plants and reduce the harmful effects of the agrochemicals on the useful organisms in the soil. Wherefore, super absorbent hydrogels were prepared by copolymerization of gum Arabic (GA) with chitosan (CS) or poly(vinyl alcohol) (PVA), and cross-linked by N,’N-methylenebisacrylamide (MBA) chemically (CH) or using sodium hexametaphosphate (SHMP) as physical (PH) cross-linker. The prepared hydrogels include PVA/GA-CH, PVA/GA-PH, CS/GA-CH and CS/GA-PH showed different degree of swelling (DS) in the following swelling medium, deionized water (DW), river water(RW) and buffer solution pH9. PVA/GA-CH and CS/GA-CH hydrogels have showed 84g/g and 63g/g maximum DS in RW respectively, while PVA/GA-PH and CS/GA-PH hydrogels have showed 81g/g and 69g/g maximum DS in pH9 respectively. The water- retention capability of some hydrogels were studied using a mixture of 0.5%(w/w) hydrogel in agricultural soil and the composite showed about 20 days extra retain of water with a control sample of soil alone. The hydrogels were loaded using urea the important fertilizer in agriculture field. The hydrogels of higher DS were only loaded, where PVA/GA-CH hydrogel has shown 89%(w/w) maximum loading percentage (Lmax%), and CS/GA-PH hydrogel reached 79.75%(w/w) of urea. The release behavior in different medium and degree of temperatures of loaded hydrogels were studied. Generally, PVA/GA-CH hydrogel have shown better release profile in RW medium at 10oC, while CS/GA-PH hydrogel showed more controlled release in pH9 medium at 30oC. Different analytical methods of SEM, FTIR of loaded hydrogel and after their release were achieved, whereas XRD,1H NMR and (TGA, DSC) of prepared hydrogels have been characterized.
REVIEW | doi:10.20944/preprints202306.0998.v1
Subject: Chemistry And Materials Science, Paper, Wood And Textiles Keywords: alkenyl succinic anhydride; ASA; cellulose; paper sizing; covalent bonding; sizing agent stability; sizing agent retention
Online: 14 June 2023 (07:16:50 CEST)
Alkenyl Succinic Anhydride (ASA) is a sizing agent used in papermaking to increase the water repellency of paper. Almost 60 years after the introduction of the chemical in papermaking, scientists still have differing views on how ASA interacts with cellulose. Several experiments were conducted to bring more clarity to the ASA sizing mechanism, especially on the contentious question of ASA-cellulose covalent bonding or the esterification reaction between ASA and cellulose during papermaking. Herein, research papers and patents, including experiments and results, from the1960’s to 2020 were reviewed. Our investigation revealed that the ester bond formation between ASA and cellulose is insignificant and is not a prerequisite for sizing effectiveness; the main ASA related material found in sized paper is hydrolyzed ASA or both hydrolyzed ASA and ASA salt. In addition, ASA emulsion stability and ASA emulsion retention are important for sizing efficiency improvement.
ARTICLE | doi:10.20944/preprints202212.0001.v1
Subject: Public Health And Healthcare, Primary Health Care Keywords: medical workforce shortage; rural and remote; recruitment and retention; sustainable rural medical workforce; medical school innitiatives.
Online: 1 December 2022 (01:05:35 CET)
.Abstract: Indonesia, one of the Asia Pacific LMICs, has suffered from a chronic medical workforce shortage. However, there are limited published studies describing the approaches implemented by the Indonesian government regarding the recruitment and retention of the medical workforce. This case study aimed to understand the current practices for recruitment and retention of the medical workforce in Indonesian rural and remote provinces. We conducted a case study of the Maluku Province of Indonesia with document analysis and key informant interviews with officials responsible for medical workforce recruitment and retention. We used the WHO’s guidelines as an analytical matrix to examine the recruitment and retention practices under four domains, i) educational, ii) regulatory, iii) financial, and iv) professional and personal development, and classified them into University/Medical School level and Government/Non-government level. Our findings suggest that Indonesia has implemented most of the WHO-recommended medical workforce recruitment and retention strategies. However, implementation is still problematic; hence, the aim of establishing an adequate, sustainable medical workforce has not been reached. Nationwide government intervention in educational aspects is important to magnify the impact of the regional medical school initiatives. Relevant programs must be re-evaluated and re-enforced concerning significance, comprehensiveness and effectiveness for sustainable rural and remote medical workforce.
ARTICLE | doi:10.20944/preprints202306.1234.v1
Subject: Environmental And Earth Sciences, Environmental Science Keywords: Water-related ecosystem services; Sediment retention; Riparian vegetation; Brazilian Forest Code; Water management; Water-Energy-Food nexus
Online: 16 June 2023 (11:24:13 CEST)
The concept of ecosystem services (ESs) provides a valuable approach to communicate societies' dependence on natural ecosystems, assisting in the evaluation of measures to protect vegetation in watersheds that promote water-related ESs. Vegetation cover and land use are important factors related to the capacity of ecosystems to provide soil loss regulation and sediment retention services, which are highly relevant for sediment management in watersheds draining into reservoirs with multiple water uses. This study aims to assess the relationship between potential changes in land use and land cover and the sediment retention service provided by riparian vegetation in a watershed draining into a hydroelectric reservoir in the Brazilian Cerrado. Sediment load was selected as a physical variable that affects different water uses in reservoirs, with these uses being dependent on the quality or quantity of stored water. Scenarios were analyzed to represent landscape reconfigurations from a baseline condition in order to account for the recovery of riparian vegetation by the agricultural sector, as foreseen in the Brazilian Forest Code. To map and quantify variations in annual sediment retention, the InVEST model was used, which allows estimating an integrated response of the drainage basin to large-scale land use changes over time and space. The results show that for the drainage basin of the Corumbá IV Hydroelectric Power Plant (HPP), the recovery of riparian areas occupied by annual crops has the potential to generate greater benefits to water use in the reservoir. In the studied catchment area, 14% of the total vegetation deficit in riparian areas is occupied by crops, while 86% is occupied by pastures. This highlights the buffering role of riparian vegetation as an effective practice for managing sediment flows originating from sheet erosion in agricultural landscapes. The methodology employed in this study allows for the quantification and mapping of the effects of soil and water conservation measures in river basins. This enables the prioritization of sectoral efforts for the restoration of native vegetation, considering the highest returns in benefits perceived by water users affected by sediment input in reservoirs. The study's results reinforce the importance of conserving vegetation in riparian areas and their surroundings for sediment retention, highlighting the role of these areas as assets in providing water-related ecosystem services.
ARTICLE | doi:10.20944/preprints202312.0286.v1
Subject: Engineering, Civil Engineering Keywords: stainless steel; standard duplex steel; lean duplex steel; post-fire strength; post-fire ductility; retention factors; recovery factors
Online: 5 December 2023 (17:03:44 CET)
Experimental quantification of retention factors related to post-fire strength as well as post-fire ductility of intentionally selected stainless steel grades applied in construction is the objective of research presented here. These steel grades are characterized by a two-phase austenitic-ferritic microstructure of the duplex type. In this context two mutually corresponding chromium-nickel-molybdenum steel grades have been subjected to analysis, namely X2CrNiMoN22-5-3 steel belonging to the standard duplex group (DSS 22% Cr) and X2CrMnNiN21-5-1 steel belonging to the lean duplex group (LDSS). The similarities and differences in the mechanical properties exhibited by these steel grades after effective cooling, following more or less prolonged simulated fire action conforming to several development scenarios, have been identified and indicated. The resistance of given steel grade to permanent structural changes induced by the heating program proved to be the critical factor determining these properties and resulting in many cases in increased susceptibility to brittle fracture.
ARTICLE | doi:10.20944/preprints202311.1500.v1
Subject: Environmental And Earth Sciences, Soil Science Keywords: Retrogressive thaw slumps; Thaw slump stages; Soil water retention; Soil organic content; Soil hydraulic properties; Qinghai-Tibet Plateau.
Online: 23 November 2023 (10:28:07 CET)
Retrogressive thaw slumps (RTSs) are becoming more common on the Qinghai-Tibet Plateau as permafrost thaws, but the hydraulic characteristics of these slumps have not been extensively studied. To fill this knowledge gap, we used the ''space-for-time substitution method'' to differentiate three stages of RTSs: original grassland, collapsing, and collapsed. Our study included on-site investigations, measurements, and simulated analyses of soil water characteristics, environmental factors, and hydrological properties. Our findings show that the measurements and simulated analyses of soil water characteristics were highly consistent across RTSs, indicating the accuracy of the V-G model in reproducing soil hydraulic parameters for different stages of RTSs. The original grassland stage had the highest soil water retention and content due to its high SOM content and fine-textured micropores. In contrast, the collapsed stage had higher soil water retention and content compared to the collapsing stage, primarily due to increased proportions of soil micropores, SOM content, and lower bulk density (BD). Freeze-thaw cycles had a significant impact on the soil texture and structure of RTSs, resulting in a decrease in SOM content and an increase in BD. However, the absence of soil structure and compaction led to the subsequent accumulation of organic matter, increasing SOM content. Changes in field capacity (FC), permanent wilting point (PWP), and soil micropore distribution aligned with variations in SOM content and water content.These findings highlight the importance of managing SOM content and water content to mitigate the adverse effects of freeze-thaw cycles on soil structure and stability at different stages of RTSs. Effective management strategies may include incorporating organic matter, reducing soil compaction, and maintaining optimal water content. Further research is needed to determine the most suitable management practices for different soil types and environmental conditions.
ARTICLE | doi:10.20944/preprints202111.0496.v1
Subject: Public Health And Healthcare, Primary Health Care Keywords: School feeding programme; Osun Elementary School Feeding and Health Programme (O-MEALS); enrolment and retention; rural pupils; primary schools
Online: 26 November 2021 (10:08:06 CET)
School Feeding Programmes are social safety net interventions providing educational and health benefits to vulnerable children in developing countries. This study assessed the impact of Osun Elementary School Feeding and Health Programme (O-MEALS) on the enrolment and retention of rural primary schools in Osun State. Multi stage sampling technique was used to select 188 respondents while data was collected through interview schedule. Percentages, Chi-square, PPMC and T-test were used for data analysis. Findings revealed that over half (51.6%) of the respondents were male, aged 9.38 ± 1.84 years and majority (83.0%) had a family size of 6-10 people. Food incentives (=1.25), health challenge (=0.69), and peer influence (=0.67) were major factors affecting school attendance. More than half (53.2%) of the respondents had unfavourable perception towards the school feeding programme. Results showed a significant difference between pupils’ enrolment (t = 5.332, p = 0.006) and retention rate (t = 58.386, p = 0.000) before and after the commencement of O-MEALS. Furthermore, pupils’ enrolment and retention (r = 0.993, p = 0.001) after the commencement of O-MEALS was significantly related. Food incentive was a major factor affecting school attendance, which fostered an improvement in the poor enrolment and retention previously experienced. Since a good number of the pupils possessed unfavourably perception towards the school feeding programme, it was recommended that effective monitoring be established to checkmate food vendors’ activities in delivering quality and satisfactory services. Likewise, the Government’s policies on school restructuring and levy, which had proved counterproductive, should be reviewed.
ARTICLE | doi:10.20944/preprints202304.0625.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: adverse drug reaction; cisplatin liposomes; circulating tumor cells; enhanced permeability and retention effect; nephrotoxicity; pulmonary metastasis of pancreatic cancer; quality of life; recurrent liver metastases from primary nasal cancer
Online: 20 April 2023 (07:52:10 CEST)
Cisplatin (CDDP) is a platinum-based drug effective against various cancers, including lung, bladder, prostate, ovarian, esophageal, stomach, and cervical cancer and malignant lymphoma. It plays a central role as the first choice in current anticancer therapy. However, CDDP causes serious side effects, such as neurological disorders, myelosuppression, and renal damage, because it is a small molecule indiscriminately distributed in normal tissues. Therefore, it is very important to prevent or attenuate CDDP toxicity. We hypothesized that liposomalization of CDDP could alleviate serious side effects. Therefore, this study aimed to evaluate the safety and efficacy of CDDP liposomes. A patient with multiple recurrent liver metastases from metastatic nasal carcinoma was administered CDDP liposomes with consent. Magnetic resonance imaging showed that the patient remained stable-diseased; however, no apparent side effects were observed, and blood draw data showed no worsening of renal function. Patients undergoing partial pancreatectomy and jejunoileal biliary anastomosis for biliary tract cancer who consented to receive CDDP liposomes demonstrated a partial response on angiographic computed tomography; however, they showed slight fatigue. To our knowledge, the present study is the first in Japan to suggest that liposomalization of CDDP may have anticancer effects while alleviating renal damage and bone marrow suppression.
ARTICLE | doi:10.20944/preprints202304.1064.v1
Subject: Public Health And Healthcare, Nursing Keywords: Nursing practice; engagement; retention; multilevel mixed methods; child and maternal health; child and family health services; progressive universalism; nurse home visiting; universal health services; nurse-parent relationship; families with complex needs; child maltreatment
Online: 27 April 2023 (09:42:43 CEST)
Family support is offered to Australian parents of young children using a mix of targeted and universal child and family health services. A feature of the universal services is the ability for nurses to work in partnership with families and to offer flexibility depending on need. This model of progressive universalism relies on the voluntary engagement of families, including families with complex needs. In this study, the capacity to engage and retain families, including those at risk for child maltreatment and family violence, was examined. Child and Family Health Nurses (n=129) participated in a pragmatic, multilevel mixed-methods study using the McCurdy and Daro (2001) Integrated Theory of Parent Involvement. A questionnaire was used in the first phase of the study to collect the quantitative data. Focus groups were then held with 27 participants recruited from phase one. Both homogeneous and heterogenous practices identified from the questionnaire were the focus of the discussions. Three phases of practice were identified and described: enrolment, retention and conclusion of the nurse-parent relationship and are presented and discussed in this paper. The retention of families with complex needs relies on flexible, advanced, and multidimensional nursing practices.