The hepatoma cell lines stably expressing sodium taurocholate cotransporting polypeptide (NTCP), the receptor of hepatitis B virus (HBV) infection, serve as important infection models for studying viral biology and drug discovery. However, the efficiency of infection greatly varies. In this study, we studied the effects and potential mechanisms of Matrigel® hESC-qualified (M-hq), a biological basement membrane matrix commonly used in cell culture, on promotion HBV in vitro infection in HepG2-NTCP cells. For the first time, our findings demonstrate that M-hq could enhance the infection efficiency of cell culture-derived HBV with no impact on the cell viability, the HBV transcription and response to antiviral treatments. The infection enhancement is reproducible and is suggested to occur at HBV attachment step. Our study suggests that this novel system is applicable for studying HBV biology and new drugs.
Dietary shifts from staples toward meats, fruits, and vegetables increase environmental impacts. Excessive red meat intake and micro-nutrient deficiencies also raise health concerns. Previous research examined environmental and health consequences of alternative diets but overlooked impacts on air pollution and land use change. Here we examine implications of four potential Chinese dietary shifts on ammonia and particulate matter (PM2.5) air pollution, greenhouse gas (GHG) emissions, carbon storage loss associated with land-use change, water use, and human health. We show that a diet that replaces red meat with soy benefits the environment and avoids 57,000 PM2.5-related premature deaths annually. Dietary health benefits, however, appear larger with adoption of the Chinese Dietary Guideline (CDG) and EAT-Lancet diets, which prevent over one million premature deaths annually. However, both diets increase water use and GHGs. CDG also increases COCs, but EAT-Lancet reduces it by cutting dairy and red meat. Complex benefits and trade-offs of dietary shifts emphasize the need for further improvements in agricultural management to enable larger health-environment co-benefits.
Epidermal electronic systems that simultaneously provide physiological information acquisition, processing, and storage are in high demand for health care/clinical applications. However, these system-level demonstrations using flexible devices are still challenging because of obstacles in device performance, functional module construction, or integration scale. Here, on the basis of carbon nanotubes, we present an epidermal system that incorporates flexible sensors, sensor interface circuits, and an integrated flash memory array to collect physiological information from the human body surface; amplify weak biosignals by high-performance differential amplifiers (voltage gain of 27 decibels, common-mode rejection ratio of >43 decibels, and gain bandwidth product of >22 kilohertz); and store the processed information in the memory array with performance on par with industrial standards (retention time of 108 seconds, program/erase voltages of ±2 volts, and endurance of 106 cycles). The results shed light on the great application potential of epidermal electronic systems in personalized diagnostic and physiological monitoring. A CNT-based epidermal system is proposed for physiological signal capturing, processing, and storage.
There are several problems concerning the statistical definition of average bioequivalence provided by U.S. Food and Drug Administration (FDA). We proposed ratio of means based on the original bioavailability measure as the definition for average bioequivalence. Under the log-normal distribution assumption, we proposed a hypothesis testing based method and a confidence interval based methods to answer the question whether the ratio of means falls into a predetermined interval. For the hypothesis testing based method, we decomposed the null two-sided hypothesis of ratio of means into two one-sided hypotheses. With the inter-section union theorem for asymptotic tests, we constructed two asymptotic size-$\alpha$ tests for the original null hypothesis. Method of variance estimation recovery was adopted to develop the confidence interval based method. Simulation studies showed that the proposed methods can maintain the empirical type-I error rate closely at the nominal level and is as powerful as two one-sided $t$-test for testing the ratio of means under different settings. The application of the proposed methods was illustrated through 6 datasets in real-world examples.
The semi-open character with high passenger flow in Metro Rail Transport Stations (MRTS) makes safety management of human-electromechanical interaction escalator systems more complex. Safety management should not consider only single failures, but also the complex interactions in the system. This study applies task driven behavior theory and system theory to reveal a generic framework of the MRTS escalator accident mechanism and uses Lasso-Logistic Regression (LLR) for escalator injury prediction. Escalator accidents in the Beijing MRTS are used as a case study to estimate the applicability of the methodologies. The main results affirm that the application of System-Theoretical Process Analysis (STPA) and Task Driven Accident Process Analysis (TDAPA) to the generic escalator accident mechanism reveals non-failure state task driven passenger behaviors and constraints on safety that are not addressed in previous studies. The results also confirm that LLR is able to predict escalator accidents where there is a relatively large number of variables with limited observations. Additionally, increasing the amount of data improves the prediction accuracy for all three types of injuries in the case study, suggesting the LLR model has good extrapolation ability. The results can be applied in MRTS as instruments for both escalator accident investigation and accident prevention.
China has put great efforts into air pollution control over the past years and recently committed to its most ambitious climate target. Cost and benefit analysis has been widely used to evaluate the control policies in terms of past performance, future reduction potential, and direct and indirect impacts. To understand the cost and benefit analysis for air pollution control in China, we conducted a bibliometric review of more than 100 studies published over the past two decades, including the current research progress, most commonly adopted methods, and core findings. The control target in cost and benefit analysis has shifted in three stages, from individual and primary pollution control, moving to joint prevention of multiple and secondary pollutants, and then towards synergistic control of air pollution and carbon. With the expansion of the research scope, the integrated assessment model has gradually demonstrated the necessity for long-term ex-anti policy simulation, especially for dealing with complex factors. To ensure long-term air quality, climate, public health, and sustainable economic development, substantial evidence from published studies has suggested that China needs to continue its efforts in the upstream adjustment of the energy system and industrial structure with multi-regional and -sector collaboration. This cost and benefit review paper provides decision-makers with the fundamental information and knowledge gaps in air pollution control strategies in China, and direction for facing future challenges.
Redox shifts threaten to reduce the massive soil organic carbon (SOC) stocks in wetlands. However, ferrous iron [Fe(II)] oxidation may stabilize wetland SOC by reducing phenol oxidative activity, inhibiting CO2 emissions, and promoting SOC association with ferric Fe [Fe(III)] (oxyhydr)oxides. Yet the prevalence and efficacy of this mechanism are not clear. Here we select six contrasting soils from fens and bogs with different pH for microcosm incubation under cyclic redox conditions, with or without Fe(II) addition, and compared to static oxic incubation. CO2 emissions, microbial composition, enzyme activities, Fe species, and organic matter properties were measured to test the related mechanism. We found that compared to static oxic conditions, the response of Fe(II) to cyclic redox conditions (indicated by the response ratio of −0.48 to 0.53) was positively correlated with that of phenol oxidative activity and cumulative CO2 at the end of the incubation. Redox cycling had little effect on Fe-bound SOC (assessed by the modified citrate-bicarbonate-dithionite extraction), although Fe(II) addition increased Fe-bound SOC in all soils under cyclic redox owing to the production of short-range-ordered Fe(III) (oxyhydr)oxides (quantified by oxalate extraction). Furthermore, Fe(II) addition decreased CO2 emissions from three soils with pH > 6 but increased CO2 emissions from the Sphagnum-dominated soil, which had elevated Fe(II) levels after the incubation. These findings highlight the SOC stabilization potential of Fe(II) addition to wetland soils experiencing redox oscillations by promoting the accumulation of Fe-bound SOC as well as decreasing CO2 emissions (in response to phenol oxidative activity), especially in non-Sphagnum-dominated freshwater wetlands with relatively high pH.