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A historic rainstorm occurred over Henan, China, in July 2021 (“7.20” extreme precipitation event), resulting in significant human casualties and socioeconomic losses. A global variable-resolution model (MPAS-Atmosphere v7.3) was employed to simulate this extreme precipitation event. A series of simulations have been done at both quasi-uniform (60 and 15 km) and variable-resolution (60–15 and 60–3 km) meshes from hydrostatic to nonhydrostatic scale with two parameterization scheme suites. For the 48 h peak precipitation duration (20–22 July), the 60–3 km variable-resolution simulation coupled with the scale-aware convection-permitting parameterization scheme suite stands out predominantly among other simulation experiments as it reproduces this extreme precipitation event most accurately. At 15 km resolution, the 60–15 km variable-resolution simulation achieves comparable forecasting skills to the 15 km quasi-uniform simulation but at a much reduced computing cost. In addition, we found that the default mesoscale suite generally outperforms the convection-permitting suite at 15 km resolution as simulations coupled with the convection-permitting suite missed the third peak of this extreme precipitation event, while the mesoscale suite did not. Furthermore, it is found that the large-scale circulation plays a critical role in the peak precipitation simulations at 15 km resolution, via influencing the simulated low-level wind. During the second peak precipitation period, simulations with the convection-permitting parameterization scheme suite at 15 km resolution generate a prominent low-level easterly wind component bias, which is largely attributed to the excessively evaporative cooling in the lower troposphere. This study further reveals that at 15 km resolution the diabatic heating from the grid-scale precipitation accounts more for the low-level wind bias than the convective-scale precipitation. Given that two different cloud microphysics schemes, namely Thompson and WSM6 schemes, are used in the convection-permitting and default mesoscale parameterization scheme suites, respectively, these microphysics schemes are found to be the primary contributor to the low-level wind simulation bias.

SUMMARY: Parasitic infections, including avian chronic haemosporidian infection, have been proven to be a major selection force affecting birds on a global scale including closely related bird species. To date, there has been limited information about haemosporidian infections in the red junglefowl (Gallus gallus) as compared to the domestic chicken (G. gallus domesticus). In this study, we collected blood samples of 39 wild red junglefowls and 122 domestic chickens to test for the presence of haemosporidian infections and various parasitic lineages. The PCR product of positive samples was sequenced, and their lineage was identified using the GenBank database. The result showed that all sampled red junglefowls tested positive for haemosporidian infection with 100% of parasite prevalence, while 104 domestic chickens tested positive (85%). Furthermore, parasite lineages were more diverse in red junglefowls compared to domestic chickens. We recommend that further research should be conducted on more populations of wild red junglefowls in comparison to the domestic chickens to ascertain the prevalence of haemosporidian parasites in association with vectors and other risk factors.

Surface reflectance data is the basic data source for the hyperspectral parametric remote sensing products and remote sensing quantitative application, which is widely used in various application fields such as natural resources and ecological environment monitoring. At present, multispectral data takes the leading role among the common land surface reflectance datasets and the reflectance data mainly involves the types of ground objects such as farmland, forest land, water body, soil, etc., while the datasets relatively less targets the types of rock and mineral surface objects, yet especially the reflectance datasets with the combination of time series and multi-scale satellite-earth are even more scarce. In order to better promote the application of hyperspectral surface reflectance and explore the advantages of joint application of satellite-earth multi-scale reflectance data, on the basis of field-measured rock and mineral target spectral, a comprehensive surface reflectance dataset was generated by using domestically produced hyperspectral satellite data as the data source in this study, mainly focusing on the typical ore concentration area in the Hami Remote Sensing test field in Xinjiang. The dataset includes multi-period hyperspectral satellite surface reflectance images, field measured rock and mineral spectral data, and multi-period sub-pixel spectral data collected based on ground spectral measured points, which can provide significant support for the research and development and accuracy verification as well as performance evaluation of algorithms such as surface reflectance inversion, mineral identification and ground object classification.

A detailed understanding of snow cover and its possible feedback on climate change on the Tibetan Plateau (TP) is of great importance. However, spatiotemporal variability in snow phenology (SP) and its influencing factors on the TP remain unclear. Based on the daily gap-free snow cover product (HMRFS-TP) with 500 m resolution, this study investigated the spatiotemporal variability in snow cover days (SCDs), snow onset date (SOD), and snow end date (SED) on the TP from 2002 to 2022. A structural equation model was used to quantify the direct and indirect effects of meteorological factors, geographical location, topography, and vegetation greenness on SP. The results indicate that the spatial distribution of SP on the TP was extremely uneven and exhibited temporal heterogeneity. SP showed vertical zonality influenced by elevation (longer SCD, earlier SOD, and later SED at higher elevations). A total of 4.62 % of the TP area had a significant decrease in SCDs, at a rate of −1.74 d yr−1. The SOD of 2.34 % of the TP area showed a significant delayed trend, at a rate of 2.90 d yr−1, while the SED of 1.52 % of the TP area had a significant advanced trend, at a rate of at −2.49 d yr−1. We also found a strong elevation dependence for the trend in SCDs (R=-0.73). Air temperature, precipitation, wind speed, and shortwave radiation can directly affect SP as well as indirectly affect it by influencing the growth of vegetation, whereas the direct effect was much greater than the indirect effect. Geographical location (latitude and longitude) and topographic conditions (elevation and slope) indirectly affected SP by modulating meteorological conditions and the growth of vegetation. Vegetation primarily influences SP by intercepting the snow and regulating the balance of the solar radiation budget. Regarding the total effect, air temperature was found to be the dominant factor. This study contributes to the understanding of snow variation in response to global warming over the past 2 decades by providing a basis for predicting future environmental and climate changes and their impacts on the TP.

Dicke state is one of the most useful multipartite quantum states. In this paper, by utilizing the method of designing the evolution operators to construct shortcuts to adiabatic passages (STAP), we have implemented the fast preparation of Dicke states |D3(2)〉 and |D4(2)〉 with one step. Specifically, with the assistance of quantum Zeno dynamics, the original Hamiltonian of the system is simplified into an effective Hamiltonian. Under the dynamic evolution of this effective Hamiltonian, the pulse control is realized by selecting two appropriate auxiliary parameters. This not only greatly shortens the evolution time but also optimizes the operation of the quantum system. In addition, we have discussed the effects of decoherence, parameter fluctuations and noise on fidelity. The results indicate that the proposed protocol maintains high fidelity. Finally, the fast preparation of Dicke state |Dn(2)〉 can be achieved based on the same method.

Film cooling protects high-temperature components and generates complex vortex structures through the interaction between the mainstream flow and the injected coolant. Additionally, the process of applying thermal barrier coatings introduces imperfect cooling holes. A numerical simulation study is conducted on two geometric configurations: inclined perfect and imperfect holes arranged in a single row on a flat plate to investigate the effects of flow field vortex structures and hole imperfections. The k-epsilon turbulent model is employed to analyse the impact of varying blowing ratios and defect positions on flow field structure and cooling efficiency, with vortex dynamics providing explanatory insights. As the blowing ratio increases, the kidney vortex associated with the perfect holes progressively detaches from the wall, reducing film cooling efficiency. The kidney vortex originates from the shear interaction between the mainstream and the impinging jet, predominantly influenced by the vortex stretching component. Imperfect holes influence the distribution state of the kidney vortex, with weakened roll-up phenomena observed at the IT4 defect location. Consequently, a noticeable enhancement in film cooling effectiveness is achieved near the proximal end of the hole.

The vibration of the leveling mill is common in metallurgical enterprises, which causes vibration marks on the surface of the support rolls and affects the surface quality of the strip. This paper establishes a bearing-rotor system model for a leveling mill, and finds that reducing the bearing clearance helps to improve the stability of the mill. The study of different speeds under the amplitude of the change, the work of the roll system gap changes on the vibration of the mill. Finally, the results of the study can provide reference for the theory of vibration suppression of rolling mills.

The rare earth metal ingots obtained by molten salt electrolysis method have oxide layers, salt layers, and other impurities on the surface, which require polishing processing. However, currently, manual polishing processing has problems such as low processing efficiency and resource waste. By designing a flexible end effector and adopting a parallel fuzzy Proportion Integration Differentiation (PID) control strategy for constant force control of the end effector, automation and high efficiency of rare earth metal ingot grinding are achieved.

Aiming at the problems of low grinding efficiency and difficulty in ensuring grinding uniformity of rare earth metal ingots, a rare earth metal ingot grinding system was designed. Based on Creo software and ANSYS/Workbench software, the kinematics analysis, modal analysis and transient dynamics analysis were carried out on the walking mechanism and flipping mechanism of automatic displacement platform of grinding system. The results show that the rare earth metal ingot grinding system has good stability and is beneficial to improving the grinding quality.

Vortex pinning is a crucial factor that determines the critical current of practical superconductors and enables their diverse applications. However, the underlying mechanism of vortex pinning has long been elusive, lacking a clear microscopic explanation. Here, using high-resolution scanning tunneling microscopy, we studied single vortex pinning induced by point defect in layered FeSe-based superconductors. We found the defect-vortex interaction drives low-energy vortex bound states away from E_{F}, creating a “mini” gap that effectively lowers the system energy and enhances pinning. By measuring the local density of states, we directly obtained the elementary pinning energy and estimated the pinning force via the spatial gradient of pinning energy. The results are consistent with bulk critical current measurement. Furthermore, we showed that a general microscopic quantum model incorporating defect-vortex interaction can naturally capture our observation. It suggests that the local pairing near pinned vortex core is actually enhanced compared to unpinned vortex, which is beyond the traditional understanding that nonsuperconducting regions pin vortices. Our study thus unveils a general microscopic mechanism of vortex pinning in superconductors and provides insights for enhancing the critical current of practical superconductors.

Remote sensing (RS) and earth observing technology are flourished with the development of a series of high-resolution earthobservation satellites. As the improvement of China’s earth observation data acquisition capability, one critical issue is put on the agenda that is what kind of models and techniques can promote the future data processing into a new level in terms of service model, massive data processing, development methods, business models, resource sharing, and system sustainability (1). In order to embed domestic satellite advantages into global world and provide increasingly more Chinese wisdom and solution to support the ASEAN regional development, China highlights the propositions on ASEAN-China remote sensing cooperation. On November 1, 2022, the ASEAN-China Satellite Remote Sensing Application Centre (hereinafter referred to as the ACSAC) was officially inaugurated in Beijing. The ACSAC will mainly focus on the establishment of a system and mechanism for a series of substantive operation, promoting the comprehensive sharing of China's land and ocean satellite data, comprehensively rich the international application scenarios of Chinese satellites, promoting applications in multiple fields and carrying out satellite remote sensing application promotion and typical demonstration, continuing to carry out technical exchanges and training with mutual demands and development. At present, ACSAC has stepped into the substantive construction stage. It will give full play to the advantages of China's natural resources land and ocean satellite remote sensing resources, to form a multi-scale, full coverage data resource support, jointly carry out the construction of the ASEAN-China satellite remote sensing data network platform based on the cloud environment, and to jointly build an integrated service open portal for land and ocean satellite data products to ASEAN region. Focusing on the core construction content of ACSAC, this paper systematically collects, summarizes and analyse the data and application needs of satellite remote sensing in ASEAN countries, finds out the current needs to meet the gap, and puts forward some thoughts and ideas on cooperation mechanism, data sharing, customized products and application demonstration of advanced products, aiming to lay a solid foundation for the substantial construction of ACSAC.

To improve the overall performance of marine centrifugal pumps (MCPs), their vibration and noise performances were optimized using the hydraulic design of the volute casing parameters considering a constant hydraulic performance at a specific speed of 66.7. Numerical simulations of the full flow field, vibration, and noise were conducted for each of five volute base circle diameters. The impact of dynamic and static disturbances on the flow and vibration and noise characteristics were investigated. These results provide some theoretical and technical support for the design and application of MCPs. The flow pattern inside the volute becomes more uniform as the D3 increases, but the pressure pulsation decreases. The total vibration levels of the inlet flange, outlet flange, and pump base decreased by 8.3%, 7.9%, and 12.3% respectively. The sound pressure of the flow noise at each characteristic frequency showed a different degree of decreasing trend.

Present and historical climate conditions jointly determine contemporary biodiversity patterns and ecosystem functions. However, it remains unclear how contemporary climate and paleoclimate changes together affect the three dimensions of biodiversity (i.e., taxonomic diversity, functional diversity and phylogenetic diversity) and their relationship with ecosystem functions. Here, we assess the impact of current climate, paleoclimate and its anomalies on contemporary biodiversity and ecosystem functions. We estimated the taxonomic, functional and phylogenetic diversity of grassland on the Mongolian Plateau using vegetation survey data and trait information. We then used random forest and structural equation models to assess the relative importance of the present, the Mid-Holocene and the Last Glacial Maximum climate as well as paleoclimate changes as determinants of diversity and aboveground biomass. Our results showed that paleoclimate changes and modern climate jointly determined contemporary biodiversity patterns, while community biomass was mainly affected by modern climate, namely the aridity index. Modern aridity and temperature were two major influences on all three dimensions of biodiversity. Mid-Holocene climate anomalies had a strong effect on species richness and phylogenetic diversity, while functional diversity had mainly been affected by temperature anomalies since the Last Glacial Maximum. These findings suggest that contemporary biodiversity patterns may be affected by processes at divergent temporal scales. Our results show that simultaneously exploring the response of the three dimensions of biodiversity in different periods of climate change and the theoretical framework for its impact on community biomass is helpful to provide a more comprehensive understanding of patterns of biodiversity and its relationship with ecosystem functions.

Compound-specific hydrogen isotopes have increasingly been used as a powerful proxy for investigating biogeochemical cycles and climate change over the past 2 decades. Understanding the hydrogen isotope in extant organisms is fundamental for us to interpret such isotope signals preserved in natural environmental samples. Here, we studied the controls on hydrogen isotope fractionation between fatty acids and growth water by an Fe-reducing heterotrophic marine bacterium Shewanella piezotolerans WP3 growing on different organic substrates, including N-acetyl-D-glucosamine (GlcNac), glucose, acetate, pyruvate, L-alanine, and L-glutamate. Meanwhile, we also evaluated the impact of growth temperature on the hydrogen isotope composition of fatty acids using GlcNac as the sole organic substrate. Our results show that the abundance-weighted mean fatty-acid / water fractionations (εFA/water) display considerable variations for cultures grown on different substrates. Specifically, WP3 yielded the most 2H-enriched fatty acids growing on L-glutamate and pyruvate with an εFA/water of 52 ± 14 ‰ and 44 ± 4 ‰, respectively, and exhibited 2H depletion using GlcNac (−76 ± 1 ‰) and glucose (−67 ± 35 ‰) as sole carbon sources and relatively small fractionations on acetate (23 ± 3 ‰) and L-alanine (−4 ± 9 ‰). Combined with metabolic model analysis, our results indicate that the central metabolic pathways exert a fundamental effect on the hydrogen isotope composition of fatty acids in heterotrophs. Temperature also has an obvious influence on the δ2H values of fatty acids, with strong 2H depletion at an optimal growth temperature (−23 ± 2 ‰ and −23 ‰ growing at 15 and 20 ∘C, respectively) and relatively small fractionations at non-optimal temperatures (4 ± 5 ‰, −4 ± 12 ‰, and 15 ± 41 ‰ at 4, 10, and 25 ∘C, respectively). We hypothesized that this may be associated with temperature-induced enzyme activity for nicotinamide adenine dinucleotide phosphate (NADPH) production. This study helps understand the controlling factors of hydrogen isotope fractionation by marine bacteria, laying the foundation for further interpreting the hydrogen isotope signatures of lipids as an important proxy to decode the biogeochemical cycles and ecological changes in marine sediments.

Summary: Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7–15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05–0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01–0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health.

To reduce the noise in a pump piping system and increase the usage time of equipment, a new type of porous muffler is proposed in this paper. A water guide cone is incorporated into the muffler structure, which may help to redirect the fluid media in the piping system. The porous structure is adapted from a muffler shell, water cone wall and round bottom plate. According to this structure, the muffler sample is made, and a pump pipeline system test bench is set up. The outlet noise of the pump pipeline system is measured after installing the muffler. At the same time, the muffler is numerically simulated by combining computational fluid mechanics and Lighthill acoustic theory. The characteristics of the flow field and external sound field under three different flow conditions of 200 m3/h, 400 m3/h and 600 m3/h are assessed. The numerical simulation results show the same dominant frequency and trend as the experimental results. The rationality of the numerical simulation is verified. Research shows that: the level of sound pressure at the muffler's outlet is lower than at the inlet, causing muffling, and the characteristics of a quadrupole sound source appear at the outlet. The proposed muffler has a certain effect in reducing noise in the pump pipeline system.

Scientific knowledge about light absorption by aerosols is extremely limited at the eastern slope of the Tibetan Plateau (ESTP). We conducted the first aerosol field experiment at six sites (Chengdu, Sanbacun, Wenchuan, Lixian, Maerkang, Hongyuan) along the ESTP, ranging in elevation from 500 to 3500 m. The fraction of light absorption by brown carbon (BrC) to total carbon increases from 20 % to 50 % with altitude, and the mass absorption efficiency (MAE) of BrC over the Tibetan Plateau (TP) is 2–3 times higher than that inside the Sichuan Basin (SCB), especially in winter. In contrast, the MAE of elemental carbon (EC) in winter decreases with altitude. The contrasting variation of EC and BrC MAE with altitude is mainly attributed to source differences between the TP and SCB. Emissions from the more urban sources (motor vehicles, industries, etc.) inside the SCB fail to be transported to the TP due to the stable air in winter inside the basin, which is also favourable for aerosol ageing to enhance absorption efficiency. The radiative forcing of BrC relative to EC varies from 0.10 to 0.42 as altitude increases with the higher organic carbon (OC) to EC ratio over the TP than SCB. Thus, the reason for the enhanced relative BrC to EC radiative forcing from polluted SCB to pristine TP is that the BrC concentration decreases more slowly than the EC concentration with altitude. This study contributes to the understanding of the difference in light absorption by EC and BrC with altitude, from polluted lower-altitude basins to the pristine TP, and provides a data set for regional climate model validation.

Abstract Background Four-dimensional flow cardiovascular magnetic resonance imaging (4D flow CMR) allows comprehensive assessment of pulmonary artery (PA) flow dynamics. Few studies have characterized longitudinal changes in pulmonary flow dynamics and right ventricular (RV) recovery following a pulmonary endarterectomy (PEA) for patients with chronic thromboembolic pulmonary hypertension (CTEPH). This can provide novel insights of RV and PA dynamics during recovery. We investigated the longitudinal trajectory of 4D flow metrics following a PEA including velocity, vorticity, helicity, and PA vessel wall stiffness. Methods Twenty patients with CTEPH underwent pre-PEA and > 6 months post-PEA CMR imaging including 4D flow CMR; right heart catheter measurements were performed in 18 of these patients. We developed a semi-automated pipeline to extract integrated 4D flow-derived main, left, and right PA (MPA, LPA, RPA) volumes, velocity flow profiles, and secondary flow profiles. We focused on secondary flow metrics of vorticity, volume fraction of positive helicity (clockwise rotation), and the helical flow index (HFI) that measures helicity intensity. Results Mean PA pressures (mPAP), total pulmonary resistance (TPR), and normalized RV end-systolic volume (RVESV) decreased significantly post-PEA (P

Background Cisgender women represent over half of people living with HIV globally. However, current research efforts toward a cure for HIV focus predominantly on cisgender men. The under-representation of women in HIV cure clinical studies is particularly problematic given data suggesting that sex-dependent phenotypes limit scientific discovery. Objective We aimed to generate considerations to increase the meaningful involvement of women in HIV cure-related research. Materials and methods We conducted in-depth interviews with biomedical researchers and community members to better understand factors that could increase the meaningful involvement of women in HIV cure clinical trials. Participants were affiliated with academia, industry, community advisory boards, and community-based organizations, and were identified using listings from the AIDS Clinical Trials Group and the Martin Delaney Collaboratories. We used conventional content analysis to analyze the qualitative data. Results We recruited 27 participants, of whom 11 were biomedical researchers and 16 were community members. Participants included 25 cisgender women, 1 transgender woman, and 1 cisgender man. Key considerations emerged, including the need to ensure that HIV cure studies reflect HIV epidemiologic trends and having accurate representation by sex and gender in HIV cure research. To increase the meaningful involvement of women, recommendations included instituting intentional enrollment goals, frequent and mandatory reporting on enrollment, and incentives for sites to enroll women. Additional themes included the need for agency and self-determination, attention to lived experiences, trauma and healing, and adequate support for women (e.g. logistical, psychosocial, mental, emotional, and physical). Participants noted that women would be willing to participate in HIV cure trials, related procedures (e.g. biopsies), and analytical treatment interruptions. They also expressed a desired for women-centered and holistic clinical trial designs that account for intersectionality. Conclusions Our empirical inquiry extends recent calls to action to increase diversity of people involved in HIV cure research. Redressing the under-inclusion of women in HIV cure research is an urgent imperative. The entire field must mobilize and reform to achieve this goal. Meaningfully involving women across the gender spectrum in HIV cure research is needed to ensure that interventions are safe, effective, scalable, and acceptable for all people with HIV.

Abstract Objectives We aimed to operationalize a head and neck microvascular free tissue transfer (MVFTT) program at a Veterans Affairs (VA) hospital with the emphasis on initiating radiotherapy within 6 weeks of surgery for cancer patients and minimizing readmissions. Study Design Case series. Setting Tertiary care VA hospital. Methods A retrospective analysis was performed on consecutive head and neck MVFTT patients from May 1, 2017 and April 30, 2022. Demographics, patient and disease characteristics, per‐operative data and postoperative outcomes were recorded from the electronic medical record. We sought to compare our rate of 30‐day readmissions with those published in the literature. Results One hundred and forty‐one procedures were performed in the queried timeframe. Eighty‐four percent (119) were performed after oncologic resections and 16% (22) were for nononcologic procedures. The rate of total flap loss was

Despite much recent effort, the highest reported T c of the infinite-layer nickelates remains lower than 15 K. Here, the authors apply pressure to Pr0.82Sr0.18NiO2 thin films and observe a monotonic increase of T c to 31 K at 12.1 GPa, an increase that does not level off with increasing pressure.

Despite antiretroviral therapy, HIV often persists in tissue sanctuary sites. In this work, authors investigate HIV persistence and T cell responses in lymph node biopsies obtained from individuals who initiated antiretroviral therapy in Fiebig stage I and beyond.

A genetic bottleneck is a hallmark of HIV-1 transmission such that only very few viral strains, termed transmitted/founder (T/F) variants establish infection in a newly infected host. Phenotypic characteristics of these variants may determine the subsequent course of disease. The HIV-1 5' long terminal repeat (LTR) promoter drives viral gene transcription and is genetically identical to the 3' LTR. We hypothesized that HIV-1 subtype C (HIV-1C) T/F virus LTR genetic variation is a determinant of transcriptional activation potential and clinical disease outcome. The 3'LTR was amplified from plasma samples of 41 study participants acutely infected with HIV-1C (Fiebig stages I and V/VI). Paired longitudinal samples were also available at one year post-infection for 31 of the 41 participants. 3' LTR amplicons were cloned into a pGL3-basic luciferase expression vector, and transfected alone or together with Transactivator of transcription (tat) into Jurkat cells in the absence or presence of cell activators (TNF-α, PMA, Prostratin and SAHA). Inter-patient T/F LTR sequence diversity was 5.7% (Renge: 2-12) with subsequent intrahost viral evolution observed in 48.4% of the participants analyzed at 12 months post-infection. T/F LTR variants exhibited differential basal transcriptional activity, with significantly higher Tat-mediated transcriptional activity compared to basal (p

The Jacobi linear iterative method and weight Jacobi method (WJM) are introduced for solving the large-scale linear problem in the proximity effect correction (PEC) of electron beam lithography. Based on the discussion of PEC physics, a symmetrical and positive defined proximity interaction matrix is constructed to ensure the convergence of the methods. It shows that zeroing the center exposure fraction in the point spread function matrix is equal to the operation of splitting the proximity interaction matrix. Then, the Jacobi method is ready for the PEC calculation. The iterative can be performed in the Fourier domain due to the inherent parallelization of the Jacobi method. The convergent property of the Jacobi method is discussed and then testified by the PEC simulation. Compared with the classical Jacobi method, an improvement of 100% in convergence efficiency can be achieved by introducing the optimized relaxation parameter quasi-ωopt in the WJM. By combining the WJM and Gold nonlinear iteration method, a new method that shows an order of magnitude superior in accuracy to the WJM is proposed. Results indicate the methods introduced here could be used to calculate the PEC problem efficiently.

Here, the authors report pressure-induced superconductivity with concomitant enhancement of antiferromagnetic transition in layered EuTe2. The superconductivity is distinctly characterized by the high upper critical fields exceeding the Pauli limit among binary tellurides, a prerequisite of the coexistence of ferromagnetism with superconductivity.

Aerosol–planetary boundary layer (PBL) interaction has been proposed as a key mechanism for stabilizing the atmosphere and exacerbating surface air pollution. Although the understanding of this process has progressed enormously, its magnitude and impact remain uncertain and vary widely concerning aerosol types, vertical distributions, synoptic conditions, etc. In this study, our primary interest is to distinguish the aerosol–PBL interaction of absorbing and scattering aerosols under contrasting synoptic patterns and aerosol vertical distributions. Detailed in situ aircraft (King Air 350) measurements and online coupled model Weather Research and Forecasting with Chemistry (WRF-Chem) simulations are explored over the North China Plain (NCP). Furthermore, a long-term PBL stability trend from 1980 to 2020 over the NCP is also investigated. The aircraft measurements and surface observations show that the surface air pollution over the city of Baoding on 3 January is heavier than that on 4 January 2020. In addition, the aerosols are restricted to the low layer on 3 January, whereas the aerosols mix more homogeneously in an upwards direction on 4 January. Thus, we focus on the 2 d with distinct synoptic circumstances, PBL stability, and aerosol vertical distributions over the NCP. According to the WRF-Chem modeling, the synoptic pattern over Baoding differs between the 2 d. The prevailing wind direction is opposite with a southwesterly wind on 3 January and a northeasterly wind on 4 January. The results indicate that the synoptic condition may affect the PBL thermal structure, thus affecting the aerosol vertical distribution. Additionally, the sensitive numerical experiments reveal that the light-absorbing and light-scattering aerosols have different effects on altering the PBL thermal structure. The inhibition effect of scattering aerosols on the PBL appears to be independent of the aerosol height distribution and solely depends on its concentration. However, the aerosol–PBL feedback of absorbing aerosols is highly dependent on its vertical distribution. Besides the 2 d case investigation, the analysis of the modeling results for nearly 1 month from 3 to 30 January 2020 in Baoding yields a more robust and representative conclusion. Our analysis highlights that we should principally concentrate on controlling the emissions of scattering aerosols under the stable stratification, while cooperating to control the emissions of scattering and absorbing aerosols in an unstable stratification. Moreover, the long-term interannual variation in the PBL stability shows a strong correlation with the East Asian winter monsoon, which seems to be valuable in determining which pollutants to target in different monsoon years and attaining more precise air pollution control. Based on the numerical simulations and observational constraints, a concept scheme description has been concluded to deepen our recognition of the interactions between thermodynamic stability and aerosols within the PBL over the NCP region.

By using the multi-source data of meteorology over recent decades, this study discovered a summertime “hollow wet pool” in the troposphere with a center of high water vapor over the Asian water tower (AWT) on the Tibetan Plateau (TP), which is indicated by a vertical transport “window” in the troposphere. The water vapor transport in the upper troposphere extends from the vertical transport window over the TP with significant connections among the Arctic, Antarctic and TP regions, highlighting the effect of the TP's vertical transport window of water vapor in the troposphere on global change in water vapor. The vertical transport window is built by the AWT's thermal forcing in association with the dynamic effect of the TP's “hollow heat island”. Our study improves the understanding of the vapor transport over the TP with important implication for global climate change.

To research the effect of the volute geometry on the radial force characteristics of the centrifugal pump during the starting process, choosing a centrifugal pump with a head of 87m as the research object. The pumping chamber is redesigned into a single-volute and a double-volute with similar external characteristics, and a circulation pipeline system is established. RNG k-ε turbulence model is employed to calculate the unsteady starting process of two kinds of centrifugal pumps. The variation trends of radial force received by the impeller and volute during the start-up process are obtained. The radial force characteristics and internal flow field evolution of two centrifugal pumps are compared and analyzed. The results show that the radial force vector distribution of the impeller changes in spiral periodicity during the startup process, and the spiral geometry is influenced by the number of impeller blades. The direction of the spiral is opposite to the rotational speed. The double-volute geometry can effectively reduce the radial force and pulsation amplitude of the impeller during the start-up process of the centrifugal pump, reducing the radial force by about 80% at rated speed. But the radial force vector distribution of the double-volute is more complicated and disordered than the single-volute.

To provide comprehensive information that will assist in making decisions regarding the adoption of lidar-assisted control (LAC) in wind turbine design, this paper investigates the impact of different turbulence models on the coherence between the rotor-effective wind speed and lidar measurement. First, the differences between the Kaimal and Mann models are discussed, including the power spectrum and spatial coherence. Next, two types of lidar systems are examined to analyze the lidar measurement coherence based on commercially available lidar scan patterns. Finally, numerical simulations have been performed to compare the lidar measurement coherence for different rotor sizes. This work confirms the association between the measurement coherence and the turbulence model. The results indicate that the lidar measurement coherence with the Mann turbulence model is lower than that with the Kaimal turbulence model. In other words, the potential value creation of LAC based on simulations during the wind turbine design phase, evaluated using the Kaimal turbulence model, will be diminished if the Mann turbulence model is used instead. In particular, the difference in coherence is more significant for larger rotors. As a result, this paper suggests that the impacts of different turbulence models should be considered uncertainties while evaluating the benefits of LAC.

Satellite remote sensing aerosol optical depth (AOD) and meteorological elements were employed to invert PM2.5 (the fine particulate matter with a diameter below 2.5 µm) in order to control air pollution more effectively. This paper proposes a restricted gradient-descent linear hybrid machine learning model (RGD-LHMLM) by integrating a random forest (RF), a gradient boosting regression tree (GBRT), and a deep neural network (DNN) to estimate the concentration of PM2.5 in China in 2019. The research data included Himawari-8 AOD with high spatiotemporal resolution, ERA5 meteorological data, and geographic information. The results showed that, in the hybrid model developed by linear fitting, the DNN accounted for the largest proportion, and the weight coefficient was 0.62. The R2 values of RF, GBRT, and DNN were reported as 0.79, 0.81, and 0.8, respectively. Preferably, the generalization ability of the mixed model was better than that of each sub-model, and R2 (determination coefficient) reached 0.84, and RMSE (root mean square error) and MAE (mean absolute error) were reported as 12.92 and 8.01 µg m−3, respectively. For the RGD-LHMLM, R2 was above 0.7 in more than 70 % of the sites and RMSE and MAE were below 20 and 15 µg m−3, respectively, in more than 70 % of the sites due to the correlation coefficient having a seasonal difference between the meteorological factor and PM2.5. Furthermore, the hybrid model performed best in winter (mean R2 was 0.84) and worst in summer (mean R2 was 0.71). The spatiotemporal distribution characteristics of PM2.5 in China were then estimated and analyzed. According to the results, there was severe pollution in winter with an average concentration of PM2.5 being reported as 62.10 µg m−3. However, there was only slight pollution in summer with an average concentration of PM2.5 being reported as 47.39 µg m−3. The period from 10:00 to 15:00 LT (Beijing time, UTC+8 every day is the best time for model inversion; at this time the pollution is also high. The findings also indicate that North China and East China are more polluted than other areas, and their average annual concentration of PM2.5 was reported as 82.68 µg m−3. Moreover, there was relatively low pollution in Inner Mongolia, Qinghai, and Tibet, for their average PM2.5 concentrations were reported below 40 µg m−3.

Abstract Background Cervicovaginal bacterial communities composed of diverse anaerobes with low Lactobacillus abundance are associated with poor reproductive outcomes such as preterm birth, infertility, cervicitis, and risk of sexually transmitted infections (STIs), including human immunodeficiency virus (HIV). Women in sub-Saharan Africa have a higher prevalence of these high-risk bacterial communities when compared to Western populations. However, the transition of cervicovaginal communities between high- and low-risk community states over time is not well described in African populations. Results We profiled the bacterial composition of 316 cervicovaginal swabs collected at 3-month intervals from 88 healthy young Black South African women with a median follow-up of 9 months per participant and developed a Markov-based model of transition dynamics that accurately predicted bacterial composition within a broader cross-sectional cohort. We found that Lactobacillus iners-dominant, but not Lactobacillus crispatus-dominant, communities have a high probability of transitioning to high-risk states. Simulating clinical interventions by manipulating the underlying transition probabilities, our model predicts that the population prevalence of low-risk microbial communities could most effectively be increased by manipulating the movement between L. iners- and L. crispatus-dominant communities. Conclusions The Markov model we present here indicates that L. iners-dominant communities have a high probability of transitioning to higher-risk states. We additionally identify transitions to target to increase the prevalence of L. crispatus-dominant communities. These findings may help guide future intervention strategies targeted at reducing bacteria-associated adverse reproductive outcomes among women living in sub-Saharan Africa. Video Abstract

HIV variants present in the reservoir, particularly in tissues, may differ from those present in peripheral blood prior to therapy initiation, and characterisation of these reservoir variants could better inform immune-based interventions for HIV cure. In the present study, Gag sequence differences between variants derived from the lymph node and peripheral blood mononuclear cell (PBMC) reservoirs as well as those derived from pre-therapy plasma, were investigated in 24 HIV-1 subtype C-infected individuals. HIV gag amplification was successful for 20 individuals, where 4 were controls including one untreated individual and 3 early treated individuals with LN collection within 2 weeks of treatment initiation. The remaining 16 individuals with LN and PBMC collection > 3 months after treatment initiation (median = 665 days), were further characterised. Recombinant viruses encoding patient-derived Gag-protease sequences from the pre-therapy plasma, LN reservoir, and PBMC reservoir, were constructed and the replication-competent viruses that grew in vitro were used to further investigate whether there are specific features of Gag reservoir variants that may have relevance for strategies to cure HIV. Virus characteristics measured included replication capacity, interferon-alpha resistance, cell-to-cell spread ability, and induction of antiviral cytokines. A limited number of novel Gag mutations (median = 4) in the reservoir of 3/7 early treated participants and 9/9 late treated participants were observed, where the majority of these mutations were likely cytotoxic T lymphocyte (CTL)-driven and 48% were represented in the replication-competent viruses. The reservoir variants had very few unique potential CTL escape mutations (median = 3) in Gag compared to the number of these Gag mutations that were already present in the plasma-derived virus (median = 23) at the time of treatment initiation, which was similar whether treatment was initiated late or early. The data suggest that the extent of CTL escape in Gag overall is likely similar between early and late treated individuals as well as between the reservoir and pre-therapy variants. The sequence differences in Gag that were unique to the reservoir viruses did not result in significantly altered virus characteristics overall, and are therefore unlikely to affect effectiveness of immune-based interventions for virus eradication.

Abstract Genomic studies have significantly improved our understanding of hepatocellular carcinoma (HCC) biology and have led to the discovery of multiple protein-coding genes driving hepatocarcinogenesis. In addition, these studies have identified thousands of new non-coding transcripts deregulated in HCC. We hypothesize that some of these transcripts may be involved in disease progression. Long non-coding RNAs are a large class of non-coding transcripts which participate in the regulation of virtually all cellular functions. However, a majority of lncRNAs remain dramatically understudied. Here, we applied a pooled shRNA-based screen to identify lncRNAs essential for HCC cell survival. We validated our screening results using RNAi, CRISPRi, and antisense oligonucleotides. We found a lncRNA, termed ASTILCS, that is critical for HCC cell growth and is overexpressed in tumors from HCC patients. We demonstrated that HCC cell death upon ASTILCS knockdown is associated with apoptosis induction and downregulation of a neighboring gene, protein tyrosine kinase 2 (PTK2), a crucial protein for HCC cell survival. Taken together, our study describes a new, non-coding RNA regulator of HCC.

Urban air pollution has tremendous spatial variability at scales ranging from kilometers to meters due to unevenly distributed emission sources, complex flow patterns, and photochemical reactions. However, high-resolution air quality information is not available through traditional approaches such as ground-based measurements and regional air quality models (with typical resolution > 1 km). Here we develop a 10 m resolution air quality model for traffic-related CO pollution based on the Parallelized Large-Eddy Simulation Model (PALM). The model performance is evaluated with measurements obtained from sensors deployed on a taxi platform, which collects data with a comparable spatial resolution to our model. The very high resolution of the model reveals a detailed geographical dispersion pattern of air pollution in and out of the road network. The model results (0.92 ± 0.40 mg m−3) agree well with the measurements (0.90 ± 0.58 mg m−3, n=114 502). The model has similar spatial patterns to those of the measurements, and the r2 value of a linear regression between model and measurement data is 0.50 ± 0.07 during non-rush hours with middle and low wind speeds. A non-linear relationship is found between average modeled concentrations and wind speed with higher concentrations under calm wind speeds. The modeled concentrations are also 20 %–30 % higher in streets that align with the wind direction within ∼ 20∘. We find that streets with higher buildings downwind have lower modeled concentrations at the pedestrian level, and similar effects are found for the variability in building heights (including gaps between buildings). The modeled concentrations also decay fast in the first ∼ 50 m from the nearest highway and arterial road but change slower further away. This study demonstrates the potential of large-eddy simulation in urban air quality modeling, which is a vigorous part of the smart city system and could inform urban planning and air quality management.

Cavitation monitoring is particularly important for pump efficiency and stability. It is easy to misjudge cavitation by using a given threshold of a single eigenvalue. In this work, based on the vibration signal, a method for multi-resolution cavitation status recognition of centrifugal pump is proposed to improve the accuracy and universality of cavitation status recognition., wavelet packet decomposition (WPD) is used to extract the statistical eigenvalues of multi-scale time-varying moment of cavitation signal after reducing the clutter, such as root mean square value, energy entropy value and so on. The characteristic matrix is constructed. Principal component analysis method (PCA) is employed to reduce the dimension of the characteristic matrix and remove the redundancy, which constructs the radial basis function (RBF) neural network as the input. The results show that the overall recognition rate of non-cavitation, inception cavitation and serious cavitation by using the vibration signal of one measuring point is more than 97.7%. The recognition rate of inception cavitation is more than 80%. Based on the vibration signal information fusion method of two measuring points, the recognition rate of centrifugal pump inception cavitation status reaches more than 99%, and the recognition rate of vibration signal information fusion method of three measuring points reaches 100% for all three cavitation statuses. Due to the influence of factors such as change of external excitation and abrupt change of working conditions, sensor data acquisition is often subjected to unpredictable disturbance. To study the ability of single-point cavitation status recognition method to resist unknown disturbances, by constantly adjusting the value of the interference coefficient of the interference term. It is found that the recognition rate of cavitation status using single measuring point decreases almost linearly with the increase of the interference coefficient. When five measuring points are used for information fusion cavitation status recognition, the cavitation status recognition rate still reaches over 90% even if the interference factor of one measuring point reaches 50%.

Abstract Introduction Immunological damage in acute HIV infection (AHI) may predispose to detrimental clinical sequela. However, studies on the earliest HIV-induced immunological changes are limited, particularly in sub-Saharan Africa. We assessed the plasma cytokines kinetics, and their associations with virological and immunological parameters, in a well-characterized AHI cohort where participants were diagnosed before peak viremia. Methods Blood cytokine levels were measured using Luminex and ELISA assays pre-infection, during the hyperacute infection phase (before or at peak viremia, 1–11 days after the first detection of viremia), after peak viremia (24–32 days), and during the early chronic phase (77–263 days). Gag-protease-driven replicative capacities of the transmitted/founder viruses were determined using a green fluorescent reporter T cell assay. Complete blood counts were determined before and immediately following AHI detection before ART initiation. Results Untreated AHI was associated with a cytokine storm of 12 out of the 33 cytokines analyzed. Initiation of ART during Fiebig stages I–II abrogated the cytokine storm. In untreated AHI, virus replicative capacity correlated positively with IP-10 (rho = 0.84, P

Rumen-protected betaine (RPB) can enhance betaine absorption in the small intestine of ruminants, while betaine can alter fat distribution and has the potential to affect the meat quality of livestock. Hence, we hypothesized that RPB might also affect the meat quality of lambs. Sixty male Hu sheep of similar weight (30.47 ± 2.04 kg) were selected and randomly subjected to five different treatments. The sheep were fed a control diet (control treatment, CTL); 1.1 g/day unprotected-betaine supplemented diet (UPB); or doses of 1.1 g/day (low RPB treatment; L-PB), 2.2 g/day (middle RPB treatment; M-PB) or 3.3 g/day (high RPB treatment; H-PB) RPB-supplemented diet for 70 days. Slaughter performance, meat quality, fatty acid and amino acid content in the longissimus dorsi (LD) muscle, shoulder muscle (SM) and gluteus muscle (GM) were measured. Compared with CTL, betaine (including UPB and RPB) supplementation increased the average daily weight gain (ADG) (P < 0.05) and average daily feed intake (P < 0.01) of lambs. Rumen-protected betaine increased ADG (P < 0.05) compared with UPB. With increasing RPB doses, the eye muscle area of the lambs linearly increased (P < 0.05). Compared with CTL, betaine supplementation decreased water loss (P < 0.05) in SM and increased pH24 in the SM (P < 0.05) and GM (P < 0.05). Compared with UPB, RPB decreased water loss in the GM (P < 0.01), decreased shear force (P < 0.05) in the LD and SM and increased the pH of the meat 24 h after slaughter (pH24). With increasing RPB doses, the shear force and b* value in the LD linearly decreased (P < 0.05), and the pH24 of the meat quadratically increased (P < 0.05). Compared with CTL, betaine supplementation increased the polyunsaturated fatty acid in the GM (P < 0.05). Compared with UPB, RPB supplementation decreased the saturated fatty acid (SFA) content in the LD (P < 0.05) and increased the unsaturated fatty acids (UFA), mono-unsaturated fatty acids and UFA/SFA ratio in the LD (P < 0.05). Compared with CTL, the content of histidine in the LD increased with betaine supplementation. Compared with UPB, RPB supplementation increased the content of total free amino acids and flavor amino acids in the LD of lambs (P < 0.05). With increasing RPB, the isoleucine and phenylalanine contents in the LD linearly increased (P < 0.05). Overall, the data collected indicated that the meat quality of lambs (especially in the LD) improved as a result of betaine supplementation, and RPB showed better effects than those of UPB.

The microbiome of the female genital tract (FGT) is closely linked to reproductive health outcomes. Diverse, anaerobe-dominated communities with low Lactobacillus abundance are associated with a number of adverse reproductive outcomes, such as preterm birth, cervical dysplasia, and sexually transmitted infections (STIs), including HIV. Vaginal dysbiosis is associated with local mucosal inflammation, which likely serves as a biological mediator of poor reproductive outcomes. Yet the precise mechanisms of this FGT inflammation remain unclear. Studies in humans have been complicated by confounding demographic, behavioral, and clinical variables. Specifically, hormonal contraception is associated both with changes in the vaginal microbiome and with mucosal inflammation. In this study, we examined the transcriptional landscape of cervical cell populations in a cohort of South African women with differing vaginal microbial community types. We also investigate effects of reproductive hormones on the transcriptional profiles of cervical cells, focusing on the contraceptive depot medroxyprogesterone acetate (DMPA), the most common form of contraception in sub-Saharan Africa. We found that antigen presenting cells (APCs) are key mediators of microbiome associated FGT inflammation. We also found that DMPA is associated with significant transcriptional changes across multiple cell lineages, with some shared and some distinct pathways compared to the inflammatory signature seen with dysbiosis. These results highlight the importance of an integrated, systems-level approach to understanding host-microbe interactions, with an appreciation for important variables, such as reproductive hormones, in the complex system of the FGT mucosa.

Human immunodeficiency virus (HIV)-induced changes in immune cells during the acute phase of infection can cause irreversible immunological damage and predict the rate of disease progression. Antiretroviral therapy (ART) remains the most effective strategy for successful immune restoration in immunocompromised people living with HIV and the earlier ART is initiated after infection, the better the long-term clinical outcomes. Here we explored the effect of ART on peripheral antigen presenting cell (APC) phenotype and function in women with HIV-1 subtype C infection who initiated ART in the hyperacute phase (before peak viremia) or during chronic infection. Peripheral blood mononuclear cells obtained longitudinally from study participants were used for immunophenotyping and functional analysis of monocytes and dendritic cells (DCs) using multiparametric flow cytometry and matched plasma was used for measurement of inflammatory markers IL-6 and soluble CD14 (sCD14) by enzyme-linked immunosorbent assay. HIV infection was associated with expansion of monocyte and plasmacytoid DC (pDC) frequencies and perturbation of monocyte subsets compared to uninfected persons despite antiretroviral treatment during hyperacute infection. Expression of activation marker CD69 on monocytes and pDCs in early treated HIV was similar to uninfected individuals. However, despite early ART, HIV infection was associated with elevation of plasma IL-6 and sCD14 levels which correlated with monocyte activation. Furthermore, HIV infection with or without early ART was associated with downmodulation of the co-stimulatory molecule CD86. Notably, early ART was associated with preserved toll-like receptor (TLR)-induced IFN-α responses of pDCs. Overall, this data provides evidence of the beneficial impact of ART initiated in hyperacute infection in preservation of APC functional cytokine production activity; but also highlights persistent inflammation facilitated by monocyte activation even after prolonged viral suppression and suggests the need for therapeutic interventions that target residual immune activation.

The dynamics of HIV-1 DNA sequences early after HIV-1 transmission remains poorly characterized. Here, the authors perform a longitudinal evaluation of HIV-1 DNA sequences in subtype C-infected individuals during acute infection, providing a landscape of the nature and evolution of the very early viral genome.

Lidar is an effective tool for high-altitude atmospheric measurement in which a weak absorption line for the target gas is selected to ensure a large optical depth. The laser frequency stabilization to the line center is required, and a sub-Doppler (sD) spectroscopy of the target line is preferred as a frequency reference. In this paper, a novel universal sD noise-immune cavity-enhanced optical heterodyne molecular spectroscopy (NICE-OHMS) instrumentation based on a fiber-coupled optical single-sideband electro-optic modulator (f-SSM) for the potential application in atmospheric lidar for different target gases with different types of lasers is reported. The f-SSM can replace all frequency actuators in the system, so as to eliminate the individual design of feedback servos that often are tailored for each laser. The universality of the instrumentation was demonstrated by the alternative use of either an Er-doped fiber laser or a whispering-gallery-mode laser. Then the instruments based on both lasers were used to produce the sD signals of acetylene, which worked as a frequency reference to stabilize the laser. By performing the lockings, relative frequency stabilizations of 8.3×10-13 and 7.5×10-13 at an integration time of 240 s were demonstrated.

Abstract In this paper, we first introduce a new algorithm which involves projecting each iteration to solve a split feasibility problem with paramonotone equilibria and using unconstrained convex optimization. The strong convergence of the proposed algorithm is presented. Second, we also revisit this split feasibility problem and replace the unconstrained convex optimization by a constrained convex optimization. We introduce some algorithms for two different types of objective function of the constrained convex optimization and prove some strong convergence results of the proposed algorithms. Third, we apply our algorithms for finding an equilibrium point with minimal environmental cost for a model in electricity production. Finally, we give some numerical results to illustrate the effectiveness and advantages of the proposed algorithms.

A cavity-enhanced photoacoustic (CEPA) sensor was developed based on an ultra-narrow linewidth whispering-gallery-mode (WGM) diode laser. A cavity-enhanced photoacoustic module (CEPAM) was designed to match the output beam from the WGM-diode laser, resulting in an increase in the excitation light power, which, in turn, significantly enhanced the photoacoustic signal amplitude. The results show that a signal gain factor of 166 was achieved, which is in excellent agreement with the power enhancement factor of 175 after considering the power transmissivity. The performance of the sensor was evaluated in terms of the detection sensitivity and linearity. A 1σ detection limit of 0.45 ppmV for C2H2 detection was obtained at atmospheric pressure with a 1 s averaging time.

In this paper, the Geometric Optics (GO)/Physical Optics (PO) method is improved to analyze the terahertz (THz)-wave scattering characteristics of objects with multiple small-scale grooves, where the grooves are of the same size. For the traditional GO/PO method, when the number of grooves reaches dozens or even hundreds, the existence of a large number of redundant intersection tests will be a main limitation to calculate the electromagnetic (EM) scattering in THz band. Therefore, in order to solve this problem, the scattered field from one of the grooves is computed using the GO/PO method and extended to obtain the scattered field of the other grooves according to their dimensional information. In this way, the computation load is effectively reduced. To demonstrate the validity of our method, the results are compared with those of MLFMM, traditional GO/PO method and experimental data. A good agreement is achieved. Meanwhile, the runtime of our method is compared with that of traditional GO/PO method, where the computational time is greatly saved. Furthermore, the scattering characteristics of objects with multiple small-scale grooves in THz band is studied. The simulation results show that the small-scale grooves will have a great effect on EM scattering characteristics in THz band.

In this study, a total of 180 one-day-old male Arbor Acres broilers were randomly allotted to 5 groups with 6 replicates per group. Birds in negative control group were fed a corn-soybean meal-based diet, and birds in positive control group, MEF group, COSE group, MEF + COSE group were challenged with E. coli K88 and supplemented with 0, 1 × 1010 cfu MEF/kg of diets, 500 mg COSE/kg of diets or their combinations, respectively. Results showed that PC group had lower average body weight and greater E. coli counts in caecal contents than NC group. MEF and COSE significantly increased average body weight, serum IgA level, T-SOD activity compared with that of PC group. MEF and MIX group had less caecal E. coli counts than PC birds. The results indicated dietary supplementation of MEF and COSE had a positive moderating effect on E. coli K88-challenged broiler chickens.

The capillary wave and initial spreading velocity in the spreading phase of drop impacting on a glass surface are studied experimentally, while the drop photos are obtained by using a high-speed video camera, which can catch up to 9000 images per second with an exposure time of 4 µs. A wide range of impact velocities are studied by varying the fall height, showing different capillary waves. All attention is given to the capillary wave and initial spreading velocity of drop. A non-linear relation between the wavelength and the impact velocity is found experimentally. Combined with the minimum spreading radius theory, a linear relation between the initial spreading velocity and the impact velocity is acquired.

HIV-1 must overcome host antiviral restriction factors for efficient replication. We hypothesized that elevated levels of bone marrow stromal cell antigen 2 (BST-2), a potent host restriction factor that interferes with HIV-1 particle release in some human cells and is antagonized by the viral protein Vpu, may associate with viral control. Using cryopreserved samples, from HIV-1 seronegative and seropositive Black women, we measured in vitro expression levels of BST-2 mRNA using a real-time PCR assay and protein levels were validated by Western blotting. The expression level of BST-2 showed an association with viral control within two independent cohorts of Black HIV infected females (r=-0.53, p=0.015, [n =21]; and r=-0.62, p=0.0006, [n=28]). DNA methylation was identified as a mechanism regulating BST-2 levels, where increased BST-2 methylation results in lower expression levels and associates with worse HIV disease outcome. We further demonstrate the ability to regulate BST-2 levels using a DNA hypomethylation drug. Our results suggest BST-2 as a factor for potential therapeutic intervention against HIV and other diseases known to involve BST-2.