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The vital role of honeybees in pollination and their high rate of mortality in the last decade have raised concern among beekeepers and researchers alike. As such, robust and remote sensing of beehives has emerged as a potential tool to help monitor the health of honeybees. Over the last decade, several monitoring systems have been proposed, including those based on in-hive acoustics. Despite its popularity, existing audio-based systems do not take context into account (e.g., environmental noise factors), and thus the performance may be severely hampered when deployed. In this paper, we investigate the effect that three different environmental noise factors (i.e., nearby train rail squealing, beekeeper speech, and rain noise) can have on three acoustic features (i.e., spectrogram, mel frequency cepstral coefficients, and discrete wavelet coefficients) used in existing automated beehive monitoring systems. To this end, audio data were collected continuously over a period of three months (August, September, and October) in 2021 from 11 urban beehives located in downtown Montréal, Québec, Canada. A system based on these features and a convolutional neural network was developed to predict beehive strength, an indicator of the size of the colony. Results show the negative impact that environmental factors can have across all tested features, resulting in an increase of up to 355% in mean absolute prediction error when heavy rain was present. [ABSTRACT FROM AUTHOR]

Bees play an important role in agriculture and ecology, and their pollination efficiency is essential to the economic profitability of farms. The drastic decrease in bee populations witnessed over the last decade has attracted great attention to automated remote beehive monitoring research, with beehive acoustics analysis emerging as a prominent field. In this paper, we review the existing literature on bee acoustics analysis and report on the articles published between January 2012 and December 2021. Five categories are explored in further detail, including the origin of the articles, their study goal, experimental setup, audio analysis methodology, and reproducibility. Highlights and limitations in each of these categories are presented and discussed. We conclude with a set of recommendations for future studies, with suggestions ranging from bee species characterization, to recording and testing setup descriptions, to making data and codes available to help advance this new multidisciplinary field. [ABSTRACT FROM AUTHOR]

Motivated by the intrinsic ferromagnetic properties and high Curie temperature of V-based Janus dichalcogenide monolayers as a new class of 2D materials, we investigated the structural, electronic and magnetic properties of the Janus VSeS monolayer by first-principles calculations. By focusing on the 2H phase, which is energetically more favorable than the 1T phase, we show that the spin orientation has a profound effect on the dynamical stability and electronic structure of the VSeS monolayer. Transition from non-magnetic to magnetic phase opens a band gap and switching from anti-ferromagnetic (AFM) to ferromagnetic (FM) phase eliminates imaginary modes of phonon dispersion and stabilizes the monolayer. Magnetic and anisotropic phase diagrams of the ferromagnetic VSeS monolayer are also studied under an applied biaxial strain. Tensile strain enhances the FM coupling by modifying through-bond and through-space interactions. Magnetic anisotropy energy is tunable by charge doping and a small carrier concentration can induce a transition from a ferromagnetic semiconductor to a half-metal. Moreover, by means of the 2D XY model, we estimate that the Berezinskii–Kosterlitz–Thouless (BKT) transition to a quasi-long-range ordered phase occurs at 83 K. We also simulate a vertical van der Waals heterostructure of VSeS/hBN to study not only the magnetic proximity effect, but also the magnetic properties of the VSeS monolayer on a substrate. The results indicate that the heterostructure is a ferromagnetic semiconductor and the VSeS monolayer preserves its magnetic properties, demonstrating high potential for application in spintronics. [ABSTRACT FROM AUTHOR]

Background: In 2020, the World Health Organization introduced cardiovascular diseases as the first cause of death. One of the common causes of this category of diseases is Myocardial Infarction. Myocardial Infarction is necrosis of the myocardium caused by an obstruction of the blood supply to the heart. The advancement of hybrid technologies such as machine learning and m-health provides a significant capacity for managing the treatment of this disease. Objective: In this study, we determine how m-health can benefit from machine learning to manage Myocardial Infarction. Material and Methods: This study is a rapid review. We applied MeSH Terms such as: Machine Learning, Telemedicine and Myocardial Infarction by Boolean operators in databases including: IEEE Xplore, ISI-web of science, Pub Med, Scopus, Science Direct and Google Scholar in recently five years. The obtained articles synthesized in accordance with the study goal. Results: Our findings showed that m-health used these models of machine learning to manage/monitor Myocardial Infarction: A) statistical learning models for processing and analyzing clinical data B) data mining algorithms for classifying clinical data and training the databases. Conclusion: The development of applications using machine learning on mobile health platforms warns more efficiently and effectively the prognosis of Myocardial Infarction and since it is accessible at any time and place, it leads to the realization of the goals of health justice in communities. [ABSTRACT FROM AUTHOR]

Supported molybdic acid on nano-Fe3O4@TiO2 (Fe3O4@TiO2@CH2)3OMoO3H) has been successfully prepared, characterized and applied as a catalyst for the synthesis of sulfonamide containing coumarin moieties. The prepared Fe3O4 nanoparticles by coprecipitation of Fe2+ and Fe3+ ions were treated with tetraethyl orthotitanate to obtain Fe3O4@TiO2. By anchoring 3-chloropropyltriethoxysilan on Fe3O4@TiO2 followed by reacting with molybdic acid, the desired catalyst was produced. The synthesized catalyst was characterized using XRD, SEM, EDS, FT-IR and VSM analysis. Fe3O4@TiO2@ CH2)3OMoO3H was used as a catalyst for the synthesis of sulfonamide containing coumarin moieties via a three-component reaction of aryl aldehydes, para-toluenesulfonamide and 4-hydroxycoumarin or 5,7-dihydroxy-4-methylcoumarin. The catalyst recovery test showed the catalyst is highly reusable without losing its activity. [ABSTRACT FROM AUTHOR]

Supported molybdic acid on nano-Fe3O4@TiO2 (Fe3O4@TiO2@(CH2)3OMoO3H) has been successfully prepared, char-acterized and applied as a catalyst for the synthesis of sulfonamide containing coumarin moieties. The prepared Fe3O4nanoparticles by coprecipitation of Fe2+ and Fe3+ ions were treated with tetraethyl orthotitanate to obtain Fe3O4@TiO2. By anchoring 3-chloropropyltriethoxysilan on Fe3O4@TiO2 followed by reacting with molybdic acid, the desired catalyst was produced. The synthesized catalyst was characterized using XRD, SEM, EDS, FT-IR and VSM analysis. Fe3O4@TiO2@(CH2)3OMoO3H was used as a catalyst for the synthesis of sulfonamide containing coumarin moieties via a three-com-ponent reaction of aryl aldehydes, para-toluenesulfonamide and 4-hydroxycoumarin or 5,7-dihydroxy-4-methylcou-marin. The catalyst recovery test showed the catalyst is highly reusable without losing its activity.

Background: The current trend of heart transplantation in recent years has taken a quantum leap forward. We decided to look back at our experience in this center., Objectives: Here, we focus on the diagnostic pitfalls and challenges in these biopsies., Patients and Methods: Forty two patients based on the standard protocol of heart transplantation group, yielded 63 biopsy samples over a period of 33 months (April 2010 - December 2012). The mean age was 30.4 years (ranging from 16 to 58 years) with 51 males (81%) and 12 females (19%). All the patients were examined periodically and biopsy samples were taken from the right ventricular wall., Results: Rarely fewer than three pieces of myocardial samples were procured. Scar, adipose tissues and blood clots may be seen instead. Quilty effect (nodular endocardial lesions composed of inflammatory cell infiltrates) was seen in 8 cases (12.7%). Other findings not directly related to rejection including early ischemic injury, Quilty effect and post-transplant lymphoproliferative disorders (PTLD) were not encountered., Conclusions: Specimen inadequacy was not a major problem in our center. It poses a great limitation, because suboptimal specimens sometimes mislead the pathologist. Other findings especially Quilty effect were within the range defined for this finding.

Anthrax lethal toxin is the major cause of death in systemic anthrax. Lethal toxin consists of two proteins: protective antigen and LF (lethal factor). Protective antigen binds to a cell-surface receptor and transports LF into the cytosol. LF is a metalloprotease that targets MKKs [MAPK (mitogen-activated protein kinase) kinases]/MEKs [MAPK/ERK (extracellular-signal-regulated kinase) kinases], cleaving them to remove a small N-terminal stretch but leaving the bulk of the protein, including the protein kinase domain, intact. LF-mediated cleavage of MEK1 and MKK6 has been shown to inhibit signalling through their cognate MAPK pathways. However, the precise mechanism by which this proteolytic cleavage inhibits signal transmission has been unclear. Here we show that the C-terminal LF-cleavage products of MEK1, MEK2, MKK3, MKK4, MKK6 and MKK7 are impaired in their ability to bind to their MAPK substrates, suggesting a common mechanism for the LF-induced inhibition of signalling.

Mitogen-activated protein kinase (MAPK) cascades control gene expression patterns in response to extracellular stimuli. MAPK/ERK (extracellular-signal-regulated kinase) kinases (MEKs) activate MAPKs by phosphorylating them; activated MAPKs, in turn, phosphorylate target transcription factors, and are deactivated by phosphatases. One mechanism for maintaining signal specificity and efficiency is the interaction of MAPKs with their substrates and regulators through high-affinity docking sites. In the present study, we show that peptides corresponding to the MAPK-docking sites of MEK1, MEK2, Ste7, Elk-1 and MAPK phosphatase (MKP)-2 potently inhibit MEK2 phosphorylation of ERK2, ERK2 phosphorylation of Elk-1, and MKP-1 dephosphorylation of ERK2. Each peptide inhibited multiple reactions; for example, the MEK2 peptide inhibited not only MEK2, but also ERK2 and MKP-1. In addition, these docking-site peptides inhibited MEK2-ERK2 binding. The MAPK-docking site of MEK1 also potently stimulated ERK2-mediated phosphorylation of a target site on the same peptide. Control peptides with mutations of conserved basic and hydrophobic residues of the MAPK-docking site consensus lacked biological activity. We conclude that MEKs, MKPs and the Elk-1 transcription factor compete for binding to the same region of ERK2 via protein-protein interactions that are crucial for kinase/phosphatase activity.