The largest part of the image encryption algorithms operates on the pixel as a central element by implementing diffusion confusion and eventually a permutation. On the other side, a permutation applied at the bit level changes not only the pixel value, but also its location within the image. In this work, we will propose a new technology of medical and color image encryption, based on chaotic permutations acting at the bit level, and a diffusion confusion ensured by an application of the method of Vigenere largely improved and adapted to the subject. Simulations performed on a large number of images of different sizes and formats ensure that our method is not subject to any known attacks.

With the prevalence of smartphones, the scope of mobile applications has been significantly broadened in the past few years including almost every aspect of our daily life. Among the applications, message dissemination services play a significant role. Traditionally, users send messages to the servers, which forward them according to friend lists. This client-server architecture is efficient with the support of infrastructures, however, it restricts the application scope and may hinder the wide deployment of location-based mobile applications. This paper proposes a novel communication model called passive broadcast for local message dissemination. In this new model, each node does not maintain a connection state and data delivery is initialized by a receiver via a ’scan’ operation. The representative carriers of passive broadcast include Bluetooth and WiFi-Direct, both of which define a mandatory ‘peer discovery’ function. Passive broadcast features negligible cost for establishing and maintaining direct links and is extremely suitable for short message dissemination in proximity. Furthermore, we study the operation management in the proposed communication model with complete protocols and in-depth analysis for optimization. We prototyped our solution on commercial phones and evaluated it with extensive experiments and simulation.

Live streaming conferences increase the participation of a diverse audience, help defray travel costs and overcome problems related to travel restrictions. In this article, we lay out tips for implementing live-streaming in scientific meetings. We also cover legal, ethical, and technical aspects implicated with live-streaming scientific talks. To write this article, we leveraged knowledge from our experience in organizing the symposium “Deciphering the Denisovans,” presented at the 88th Annual Meeting of the American Association of Physical Anthropology (AAPA) in Cleveland, OH, in 2019, as well as literature on the topic.

This document introduces a new cryptosystem mixing two improvement standards generally used for text encryption, in order to give birth a new color image encryption algorithm capable of dealing with known attacks. Firstly, two substitution matrixes attached to a strong replacement function will be generated for advanced Vigenere technique application. At the end of this first round, the output vector is subdivided into size blocks according to the used chaotic map, for acting a single enhanced Hill circuit insured by a large inversible matrix. A detailed description of such a large involutive matrix constructed using Kronecker products will be given. accompanied by a dynamic translation vector to eliminate any linearity. A solid chaining is established between the encrypted block and the next clear block to avoid any differential attack. Simulations carried out on a large volume of images of different sizes and formats ensure that our approach is not exposed to any known attacks.

Balanced nitrogen (N) and phosphorus (P) rates coupling with rational fertilization methodology could promote crop N accumulation, N use efficiency and yield production, particularly in semi-arid and arid regions. To test these characteristics, a two-year (2018 and 2019) pot experiment was therefore performed by growing summer maize in a rain-proof glass greenhouse, under 9 combined N (112, 150 and 187 kg ha-1, urea) and P (45, 60, 75 kg ha-1, calcium superphosphate) rates and three contrasting fertilizer placements. The fertilizers were placed by broadcast on soil surface (Broadcast), side band on 4 cm strip soil surface within 7 cm from sowing line (Side band) and deep band on 4 cm strip below 7 cm soil depth within 7 cm from sowing line (Deep band). Results from three maize growth stages (eight-leaf, 45 days after sowing, DAS; tasseling, 60 DAS; and harvest, 115 DAS) showed that leaf, stem, root N accumulation and total soil N were significantly increased under Deep band than under both Side band and Broadcast at N150P60, N187P60, N150P75 and N187P75, but not at N112P45, N150P45, N187P45, N112P60 and N112P75. Significantly greater leaf, stem, and root N accumulations were also displayed at N150 and N187 than at N112 for the same P60 or P75 under Deep band at 60 DAS and 115 DAS, while were for leaf and stem N accumulations at P75 and P60 than at P45 for the same N150 under Deep band at 45 DAS, 60 DAS and 115 DAS. Significantly greater agronomy N use efficiency, partial factor productivity and N use efficiency exhibited under Deep band than under Side band and Broadcast at N150P75 and N187P75, but at N150P60 and N187P60 for NUE only. In addition, leaf, stem, seed, root N concentrations positively correlated with their own N accumulations or soil N concentration at tasseling and harvest stages. Our results demonstrate that a synchronized N150P60, N187P60, N150P75 or N187P75 fertilization rate with Deep band placement can improve soil N availability and root N uptake, and hereby greater aboveground N accumulation, N use efficiency and yield production of maize particularly practical for small-holder farmers globally.