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Two-dimensional (2D) piezoelectric nanomaterials have widely been studied recently due to their promise for various applications in technology. Investigation of vertical piezoelectricity will contribute to a deeper understanding of the intrinsic mechanism of piezoelectric effects in the 2D structures. In this paper, we report a first-principle study for the structural, electronic, piezoelectric, and transport properties of new-designed Janus WSi Z 3 H (Z = N, P, and As) monolayers. The structural stability of WSi Z 3 H is theoretically confirmed based on the energetic, phonon dispersion, and also elastic analyses. At the ground state, while WSiN 3 H is an indirect semiconductor, both WSiP 3 H and WSiAs 3 H are predicted to be direct semiconductors with smaller bandgaps. When the spin-orbit coupling effects are taken into account, a large valley spin splitting is observed at the K point of WSi Z 3 H materials. Interestingly, a giant Rashba spin splitting is found in WSiP 3 H and WSiAs 3 H with Rashba constant α R up to 770.91 meV Å. Additionally, our first-principles study indicates that Janus WSi Z 3 H monolayers are piezoelectric semiconductors with high out-of-plane piezoelectric coefficient | d 31 | , up to 0.15 pm/V, due to the broken mirror symmetry. Besides, with high electron mobilities and also possessing direct band gaps, WSiP 3 H and WSiAs 3 H monolayers are favorable for applications in optoelectronics. [ABSTRACT FROM AUTHOR]

Li Li,1 Rongjin Sun,1 Joseph Zenga,2 Heather Himburg,3 Lu Wang,1 Shengnan Duan,1 Jingwen Liu,1 Dinh Bui,1 Zuoxu Xie,1 Ting Du,4 Lijun Xie,1 Taijun Yin,1 Stu Wong,2 Song Gao,4 Ming Hu1 1Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX, USA; 2Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, Milwaukee, WI, USA; 3Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI, USA; 4Department of Pharmaceutical Science, College of Pharmacy and Health Sciences, Texas Southern University, Houston, TX, USACorrespondence: Ming Hu, Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX, USA, Email mhu@uh.edu Song Gao, Department of Pharmaceutical Science, College of Pharmacy and Health Sciences, Texas Southern University, Houston, TX, USA, Email Song.Gao@tsu.eduObjective: We aim to quantify the absolute protein expression of cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) in various cells and tissues to determine the relative contribution of COX-1 and COX-2 to PGE2 production.Methods: An LC-MS method was developed and validated, then used for quantifying the absolute amounts of COX-1 and COX-2 in recombinant human COX-1 and COX-2, lysates from different cells, tissue microsomes of rodents and humans, Pirc rat colonic polyps, and biopsy specimens from squamous cell carcinoma (SCC) patients. The COX-1 and COX-2 turnover numbers were subsequently calculated based on apparent formation rates of PGE2.Results: A robust LC-MS method for quantification of COX-1 and COX-2 was developed and validated and then used to calculate their apparent turnover numbers. The results showed that COX-1 expression levels were much higher than that of COX-2 in all the tested tissues including the colonic epithelium of F344 (28-fold) and Pirc rats (20-fold), colonic polyps of Pirc rats (8-fold), and biopsy specimens of SCC patients (11– 17-fold). In addition, both COX-1 and COX-2 were higher in polyps when compared to adjacent mucosa of Pirc rats. The turnover number of recombinant human COX-2 was 14-fold higher than that of recombinant human COX-1. LPS stimulation increased COX-2 protein expression in three cell lines (Raw 264.7, SCC9 and EOMA) as expected but unexpectedly increased COX-1 protein expression (13.8-fold) in EOMA cells.Conclusion: In human oral cancer tissues and cells as well as Pirc rat colon, COX-1 plays an unexpectedly but more important role than COX-2 in abnormal PGE2 production since COX-1 expression is much higher than COX-2. In addition, COX-1 expression levels are inducible in cells, and higher in polyps than surrounding mucosa in Pirc rat colon. These results indicate that targeted suppression of local COX-1 should be considered to reduce colon-specific PGE2-mediated inflammation.Graphical Abstract: Keywords: cyclooxygenase-1, cyclooxygenase-2, turnover number, inflammation, absolute quantification, liquid chromatography with tandem mass spectrometry

In this paper, we investigate the optical response of the PbBiI single-layer by developing a strain-induced Kane–Mele model from Peierls substitution and by employing the Kubo formula at low temperatures. We address three different regimes of uniform and non-uniform classes created by tuning the strength of the strain. From a detailed analysis of the electronic band structure, we find that the Rashba spin splitting gap is destroyed with strain, while the bulk gap slightly changes. We also find that interband optical transitions exhibit a blueshift spectrum with strain. Interestingly, all these findings are independent of the regime and class of strain. However, our simulations show that only the non-uniform class of strain leads to anisotropic optical conductivity. These results enhance optoelectronic applications of low-dimensional materials. [ABSTRACT FROM AUTHOR]

In this study, using the tight-binding model and Green's function technique, we investigate potential electronic phase transitions in bilayer P6mmm borophene under the influence of external stimuli, including a perpendicular electric field, electron–hole coupling between sublayers (excitonic effects), and dopants. Our focus is on key electronic properties such as the band structure and density of states. Our findings reveal that the pristine lattice is metal with Dirac cones around the Fermi level, where their intersection forms a nodal line. The system undergoes transitions to a semiconducting state – elimination of nodal line – with a perpendicular electric field and a semimetallic state – transition from two Dirac cones to a single Dirac cone – with combined electric field and excitonic effects. Notably, with these, the system retains its massless Dirac-like bands characteristic at finite energy. However, introducing a dopant still leads to a metallic phase, but the Dirac-like bands become massive. Considering all these effects, the system ultimately reaches a semiconducting phase with massive Dirac-like bands. These results hold significance for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Kate Nguyen,1 Dinh Bui,2 Mahak Hashemi,1,3 Dianna M Hocking,4 Priyan Mendis,3 Richard A Strugnell,4 Shyamali C Dharmage2 1School of Engineering, RMIT University, Melbourne, Victoria, Australia; 2Centre of Epidemiology and Biostatistics, The University of Melbourne, Melbourne, Victoria, Australia; 3ARC Training Centre on Advanced Manufacturing of Prefabricated Housing, The University of Melbourne, Melbourne, Victoria, Australia; 4Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, AustraliaCorrespondence: Shyamali C Dharmage Email s.dharmage@unimelb.edu.auAbstract: This work is part of a project on the development of a smart prefabricated sanitising chamber (SPSC) to provide extra measures against the transmission of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Stabilised hypochlorous acid (HOCl) is an approved disinfectant against SARS-CoV-2 by the Environmental Protection Association US in its liquid form on non-porous surfaces. This review is extended to cover its viricidal/bactericidal efficacy in aerosolised or sprayed form which showed an effective dose of as low as 20 ppm and the exposure duration of at least 60 s. The aerosolised application was also recommended with particle size of less than 200 μm to increase the contact with pathogens. The review also includes the safety and toxicity of HOCl with different concentrations. The review calls for more investigations into the effect of HOCl in mist and fog form on the respiratory system when transitioning through the proposed SPSC.Keywords: SARS-CoV-2, Sanitiser, occupational health, cross-contamination, healthcare management

Internet of Things (IoT) and its applications are becoming commonplace with more devices, but always at risk of network security. It is therefore crucial for an IoT network design to identify attackers accurately, quickly and promptly. Many solutions have been proposed, mainly concerning secure IoT architectures and classification algorithms, but none of them have paid enough attention to reducing the complexity. Our proposal in this paper is an edge-cloud architecture that fulfills the detection task right at the edge layer, near the source of the attacks for quick response, versatility, as well as reducing the Cloud's workload. We also propose a multi-attack detection mechanism called LocKedge (Low-Complexity Cyberattack Detection in IoT Edge Computing), which has low complexity for deployment at the edge zone while still maintaining high accuracy. LocKedge is implemented in two manners: centralized manner and federated learning manner in order to verify the performance of the architecture from different perspectives. The performance of our proposed mechanism is compared with that of other machine learning and deep learning methods using the most updated BoT-IoT data set. The results show that LocKedge outperforms other algorithms such as NN, CNN, RNN, KNN, SVM, KNN, RF and Decision Tree in terms of accuracy and NN in terms of complexity.

Source localization models assume brain electrical conductivities are isotropic at about 0.33 S/m. These assumptions have not been confirmed ex vivo in humans. This study determined bidirectional electrical conductivities from pediatric epilepsy surgery patients. Electrical conductivities perpendicular and parallel to the pial surface of neocortex and subcortical white matter (n = 15) were measured using the 4-electrode technique and compared with clinical variables. Mean (±SD) electrical conductivities were 0.10 ± 0.01 S/m, and varied by 243% from patient to patient. Perpendicular and parallel conductivities differed by 45%, and the larger values were perpendicular to the pial surface in 47% and parallel in 40% of patients. A perpendicular principal axis was associated with normal, while isotropy and parallel principal axes were linked with epileptogenic lesions by MRI. Electrical conductivities were decreased in patients with cortical dysplasia compared with non-dysplasia etiologies. The electrical conductivity values of freshly excised human brain tissues were approximately 30% of assumed values, varied by over 200% from patient to patient, and had erratic anisotropic and isotropic shapes if the MRI showed a lesion. Understanding brain electrical conductivity and ways to non-invasively measure them are probably necessary to enhance the ability to localize EEG sources from epilepsy surgery patients.

We explore the implementation of specific optical properties of armchair graphene nanoribbons (AGNRs) through edge-defect manipulation. This technique employs the tight-binding model in conjunction with the calculated absorption spectral function. Modification of the edge states gives rise to the diverse electronic structures with striking changes in the band gap and special flat bands at low energy. The optical-absorption spectra exhibit unique excitation peaks, and they strongly depend on the type and period of the edge extension. Remarkably, there exist the unusual transition channels associated with the flat bands for selected edge-modified systems. We discovered the special rule governing how the edge-defect influences the electronic and optical properties in AGNRs. Our theoretical prediction demonstrates an efficient way to manipulate the optical properties of AGNRs. This might be of importance in the search for suitable materials designed to have possible technology applications in nano-optical, plasmonic and optoelectronic devices.

Introduction: People who inject drugs (PWID) experience high HIV incidence and face significant barriers to engagement in HIV care and substance use treatment. Strategies for HIV treatment as prevention and substance use treatment present unique challenges in PWID that may vary regionally. Understanding differences in the risk structure for HIV transmission and disease progression among PWID is essential in developing and effectively targeting intervention strategies of HIV treatment as prevention. Methods: We present a baseline analysis of HIV Prevention Trials Network (HPTN) 074, a two-arm, randomized controlled trial among PWID in Indonesia (n = 258), Ukraine (n = 457) and Vietnam (n = 439). HPTN 074 was designed to determine the feasibility, barriers and uptake of an integrated intervention combining health systems navigation and psychosocial counselling for the early engagement of antiretroviral therapy (ART) and substance use treatment for PWID living with HIV. Discordant PWID networks were enrolled, consisting of an HIV-positive index and their HIV-negative network injection partner (s). Among the enrolled cohort of 1154 participants (502 index participants and 652 network partners), we examine regional differences in the baseline risk structure, including sociodemographics, HIV and substance use treatment history, and injection and sexual risk behaviours. Results: The majority of participants were male (87%), with 82% of the enrolled females coming from Ukraine. The overall mean age was 34 (IQR: 30, 38). Most commonly injected substances included illegally manufactured methadone in Ukraine (84.2%), and heroin in Indonesia (81.8%) and Vietnam (99.5%). Injection network sizes varied by region: median number of people with whom participants self-reported injecting drugs was 3 (IQR: 2, 5) in Indonesia, 5 (IQR: 3, 10) in Ukraine and 3 (IQR: 2, 4) in Vietnam. Hazardous alcohol use, assessed using the Alcohol Use Disorders Identification Test--Alcohol Consumption Questions (AUDIT-C), was prominent in Ukraine (54.7%) and Vietnam (26.4%). Reported sexual risk behaviours in the past month, including having two or more sex partners and giving/receiving money or drugs in exchange for sex, were uncommon among all participants and regions. Conclusions: While regional differences in risk structure exist, PWID particularly in Ukraine need immediate attention for risk reduction strategies. Substantial regional differences in risk structure will require flexible, tailored treatment as prevention interventions for distinct PWID populations. Keywords: injection drug use; PWID; HIV; substance use treatment; ART; treatment as prevention, 1 | INTRODUCTION HIV epidemics in eastern Europe, central Asia and many parts of South East Asia are concentrated among people who inject drugs (PWID) [1]. Serial use and sharing [...]