46 research outputs found
Selective Combining for Hybrid Cooperative Networks
In this study, we consider the selective combining in hybrid cooperative
networks (SCHCNs scheme) with one source node, one destination node and
relay nodes. In the SCHCN scheme, each relay first adaptively chooses between
amplify-and-forward protocol and decode-and-forward protocol on a per frame
basis by examining the error-detecting code result, and () relays will be selected to forward their received signals to the
destination. We first develop a signal-to-noise ratio (SNR) threshold-based
frame error rate (FER) approximation model. Then, the theoretical FER
expressions for the SCHCN scheme are derived by utilizing the proposed SNR
threshold-based FER approximation model. The analytical FER expressions are
validated through simulation results.Comment: 27 pages, 8 figures, IET Communications, 201
Genomewide association studies of suicide attempts in US soldiers
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/139960/1/ajmgb32594.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139960/2/ajmgb32594_am.pd
Monochromatic X-ray imaging using a combination of doubly curved crystal and polycapillary X-ray lens
Graphene/graphene nanoribbon aerogels decorated with S-doped MoSe2 nanosheets as an efficient electrocatalyst for hydrogen evolution
Searching for an efficient and cost effective electrochemical catalyst is regarded as the key challenge for the hydrogen evolution reaction (HER). Both the active sites and electrical conductivity of the catalysts should be carefully engineered to improve their HER performance. In this work, S-doped MoSe2-decorated graphene/graphene nanoribbon aerogel (S-MoSe2@GGNR) hybrids have been fabricated as high-performance electrocatalysts for HER. The unique nanoribbon-interconnected-nanosheet structure of the graphene/graphene nanoribbon aerogel (GGNR) provides an open structure for fast ion diffusion and conductive channels for fast electron transport. GGNR as a substrate could prevent MoSe2 nanosheets from agglomeration and fully expose the active sites of MoSe2, while further S-doping can modify its electronic and crystalline structure, which can improve the activity of the catalytic sites. Consequently, the S-MoSe2@GGNR hybrids exhibit outstanding electrochemical activity with a potential of −153 mV vs. reversible hydrogen electrode to achieve a current density of 10.0 mA cm−2 and a small Tafel slope of 46 mV per decade. The good performance of the S-MoSe2@GGNR hybrids can be credited to synergistic effects between the unique hierarchical architecture of carbon aerogels and positive effect of S-doping, which makes them promising electrocatalysts for hydrogen production.The authors are grateful for the financial support from the National Natural Science Foundation of China (21704014, 51433001, and 21674019), Science and Technology Commission of Shanghai Municipality (16520722100), the Fundamental Research Funds for the Central Universities (2232017D-06), Shanghai Municipal Education Commission (17CG33), Shanghai Sailing Program (17YF1400200), and Program of Shanghai Academic Research Leader (17XD1400100)
Cardiac rehabilitation engagement and associated factors among heart failure patients: a cross-sectional study
Abstract Background Chronic Heart Failure (CHF) still affects millions of people worldwide despite great advances in therapeutic approaches in the cardiovascular field. Cardiac rehabilitation (CR) is known to improve disease-related symptoms, quality of life and clinical outcomes, yet implementation is suboptimal, a frequently low engagement in rehabilitation programs has been found globally. Objective To quantify diverse CR-engaged processes and elucidate associated factors of the various levels of CR engagement in CHF patients. Methods Discharged patients admitted from cardiology departments between May 2022 to July 2022 were enrolled by mobile phone text messaging, CHF patients from same department between August 2022 to December 2022 were enrolled by face-to-face. Individuals who met the inclusion criteria filled the questionnaires, including the generalized anxiety disorders scale, patient health questionnaire, cardiac rehabilitation inventory, patient activation measure, Tampa scale for kinesiophobia heart, social frailty, Patient Health Engagement Scale (PHE-s®). We obtained sociodemographic characteristics and clinical data from medical records. Chi-square tests and multivariable logistic regression analyses were performed to examine the factors associated with CR engagement phases. Results A total of 684 patients were included in the study. 52.49% patients were in the Adhesion phase. At the multivariate level, compared with the blackout phase process anxiety, monthly income (RMB yuan) equal to or more than 5,000 were the most important factor impacting CHF patients CR engagement. Compared with the Blackout phase, regular exercise or not, severe depression, previous cardiac-related hospitalizations 1 or 2 times, Age influenced patient CR engagement in the Arousal phase. Besides, compared with the Blackout phase, outcome anxiety and activation level were independent factors in the Eudaimonic Project phase. Conclusion This study characterized CR engagement, and explored demographic, medical, and psychological factors—with the most important being process anxiety, monthly income, patient activation, severe depression, and previous cardiac-related hospitalizations. The associated factors of CR engagement were not identical among different phases. Our findings suggested that factors could potentially be targeted in clinical practice to identify low CR engagement patients, and strategies implemented to strengthen or overcome these associations to address low CR engagement in CHF patients
Hydrogen-bonded network enables polyelectrolyte complex hydrogels with high stretchability, excellent fatigue resistance and self-healability for human motion detection
Polyelectrolyte complex hydrogel (PECH) is an emerging ion conductive hydrogel made from non-covalent interacted oppositely charged polyelectrolytes in water. However, the construction of PECH with high stretchability, excellent fatigue resistance and self-healability is heavily demanded while remaining a profound challenge. Herein, a hydrogen-bonded network densification strategy is presented for preparing a highly stretchable and deformation-tolerant PECH hydrogel (Fe/CS/PAA), which is composed of an anionic Fe3+-coordinated polyacrylic acid network (Fe-PAA) and cationic Fe3+-coordinated chitosan network (Fe-CS). Benefiting from the formation of dense hydrogen-bonded network between the Fe-PAA and Fe-CS networks activated by salt impregnation, the resultant densified hydrogen-bonded Fe/CS/PAA hydrogel (DHB-Fe/CS/PAA) exhibits large tensile strength (~0.34 MPa), high stretchability (~1370%), low-temperature resistance to −25 °C, and heat-accelerated self-healability. Due to its high stretchability, excellent fatigue resistance and high ionic conductivity, the DHB-Fe/CS/PAA can readily work as a stretchable ionic conductor for skin-inspired ionic strain sensor, displaying high sensitivity in a wide strain range (0.5%–500%), fast response time (<180 ms) and excellent durability for 500 cycles at a 100% strain. Besides, the as-assembled ionic sensor is capable of maintaining high ionic conductivity and mechanical robustness at a sub-zero temperature of −25 °C ascribing to the presence of high-concentration charged functional groups and impregnated salts. As a demonstration, a wearable DHB-Fe/CS/PAA ionic sensor in a resistive mode is assembled, demonstrating high sensitivity, wide response range and excellent cyclability in detecting and distinguishing complex human motions rapidly and in real-time.</p
Med. Chem. Res.
The monoacylglycerol lipase (MAGL) regulates 2-arachidonoyl glycerol (2-AG) level in the endocannabinoid system (ECS), which is implicated in a number of severe diseases such as cancer and Alzheimer's disease. However, most existing MAGL inhibitors also show additional inhibitory effects on fatty acid amide hydrolase (FAAH), another member of the ECS that degrades the 2-AG analog N-arachidonoyl ethanolamine. Understanding of molecular mechanism and biological implication underlying the specific interactions in MAGL-ligand recognition is thus fundamentally important for the rational design of selective MAGL inhibitors. In the current study, the structural basis and energetic property regarding the binding of several MAGL inhibitors as well as its substrate 2-AG to both the MAGL and FAAH are investigated systematically by integrating molecular docking, quantum mechanics/molecular mechanics analysis, and Poisson-Boltzmann/surface area solvent model. In addition, a novel quantitative structure-selectivity relationship method is proposed to help in the explanation and prediction of inhibitor selectivity between MAGL and FAAH. It is suggested that the selectivity is primarily determined by the size, topology, and property of the rear moiety of inhibitor compounds; a bulky, bifurcated rear is the prerequisite for a inhibitor to have high selectivity for MAGL over FAAH, whereas those dual-type MAGL-FAAH inhibitors should possess a small, rear moiety-the ideal choice is a single aromatic branch occupying this position.The monoacylglycerol lipase (MAGL) regulates 2-arachidonoyl glycerol (2-AG) level in the endocannabinoid system (ECS), which is implicated in a number of severe diseases such as cancer and Alzheimer's disease. However, most existing MAGL inhibitors also show additional inhibitory effects on fatty acid amide hydrolase (FAAH), another member of the ECS that degrades the 2-AG analog N-arachidonoyl ethanolamine. Understanding of molecular mechanism and biological implication underlying the specific interactions in MAGL-ligand recognition is thus fundamentally important for the rational design of selective MAGL inhibitors. In the current study, the structural basis and energetic property regarding the binding of several MAGL inhibitors as well as its substrate 2-AG to both the MAGL and FAAH are investigated systematically by integrating molecular docking, quantum mechanics/molecular mechanics analysis, and Poisson-Boltzmann/surface area solvent model. In addition, a novel quantitative structure-selectivity relationship method is proposed to help in the explanation and prediction of inhibitor selectivity between MAGL and FAAH. It is suggested that the selectivity is primarily determined by the size, topology, and property of the rear moiety of inhibitor compounds; a bulky, bifurcated rear is the prerequisite for a inhibitor to have high selectivity for MAGL over FAAH, whereas those dual-type MAGL-FAAH inhibitors should possess a small, rear moiety-the ideal choice is a single aromatic branch occupying this position
Advances in rapid detection of common mycotoxins in food based on spectral technology
Mycotoxins are widely present in foods,espacially in cereals and cereal products.It does serious harms to the safety and health of humans and animals.With the development of chromatographic techniques,immunochemical,spectroscopy,electricity and other areas,the methods to detect the presence of mycotoxins have been diversified.However,all these methods have both advantages and disadvantages under the current situation,as a result,how to detect mycotoxins fastly,sensitively,accurately and conveniently turns out to be highly desirable.This review introduces several mycotoxins,as well as their limit standards and the present situations of mycotoxin detection.An optical based technique named Raman and its applications in detecting different mycotoxin have also been described
Activity and Mechanism of Action of Antifungal Peptides from Microorganisms: A Review
Harmful fungi in nature not only cause diseases in plants, but also fungal infection and poisoning when people and animals eat food derived from crops contaminated with them. Unfortunately, such fungi are becoming increasingly more resistant to traditional synthetic antifungal drugs, which can make prevention and control work increasingly more difficult to achieve. This means they are potentially very harmful to human health and lifestyle. Antifungal peptides are natural substances produced by organisms to defend themselves against harmful fungi. As a result, they have become an important research object to help deal with harmful fungi and overcome their drug resistance. Moreover, they are expected to be developed into new therapeutic drugs against drug-resistant fungi in clinical application. This review focuses on antifungal peptides that have been isolated from bacteria, fungi, and other microorganisms to date. Their antifungal activity and factors affecting it are outlined in terms of their antibacterial spectra and effects. The toxic effects of the antifungal peptides and their common solutions are mentioned. The mechanisms of action of the antifungal peptides are described according to their action pathways. The work provides a useful reference for further clinical research and the development of safe antifungal drugs that have high efficiencies and broad application spectra
Clostridium thermocellum Nitrilase Expression and Surface Display on Bacillus subtilis Spores
Nitrilases are an important class of industrial enzymes. They require mild reaction conditions and are highly efficient and environmentally friendly, so they are used to catalyze the synthesis of carboxylic acid from nitrile, a process considered superior to conventional chemical syntheses. Nitrilases should be immobilized to overcome difficulties in recovery after the reaction and to stabilize the free enzyme. The nitrilase from Clostridium thermocellum was expressed, identified and displayed on the surface of Bacillus subtilis spores by using the spore coat protein G of B. subtilis as an anchoring motif. In a free state, the recombinant nitrilase catalyzed the conversion of 3-cyanopyridine to niacin and displayed maximum catalytic activity (8.22 units/mg protein) at 40 degrees C and pH 7.4. SDS-PAGE and Western blot were used to confirm nitrilase display. Compared with the free enzyme, the sporeimmobilized nitrilase showed a higher tolerance for adverse environmental conditions. After the reaction, recombinant spores were recovered via centrifugation and reused 3 times to catalyze the conversion of 3-cyanopyridine with 75.3% nitrilase activity. This study demonstrates an effective means of nitrilase immobilization via spore surface display, which can be applied in biological processes or conversion. (C) 2015 S. Karger AG, Basel</p