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We report an unexpected direct transfer hydrogenation (TH) from 8-alkoxyjulolidine as a strong electron donor to tricyanofuran-based hemicyanines and tandem condensation for the synthesis of push–pull chromophores. Density functional theory calculations identify the α-hydride transfer of julolidine derivatives, instead of nucleophilic addition, as the key initial step of reaction cascades, followed by efficient β-deprotonation to generate a nucleophilic enamine of isojuloline that condenses in situ with a second equivalent of hemicyanines as electrophiles. The scheme represents an exceptional example of TH reactions from 8-alkoxyjulolidine to highly polarizable hemicyanines, notably under simple reaction conditions without using potent catalysts of metal complexes or Lewis acids. The resulting products of isojuloline-based merocyanines exhibit strong near-infrared (NIR) absorption and large first hyperpolarizabilities. The study suggests that direct TH can be exploited to construct new NIR merocyanines by following rational, regioselective condensation pathways for photonic applications. [ABSTRACT FROM AUTHOR]

A new catalytic combustion hydrogen (H 2) sensor is developed using the electrodeposition method and the Pd catalyst layer is directly deposited on a Pt filament without carrier. The sensing performance was investigated by altering the electroplating time to control the thickness of the Pd catalyst layer. The sensitivity is changed with the increase of the Pd layer's thickness and the highest sensitivity (26.8) was obtained when the thickness is 1.635 μm. In addition, the new sensor exhibits great selectivity, while having the advantages of low power consumption (25 mW) and high vibration resistance. The achievement of this carrier-free sensor is expected to meet the requirement for H 2 energy vehicles. • A carrier-free catalytic combustion H 2 sensor has been fabricated using the electrodeposition method. • The influence of catalytic layer on sensing performance was discussed. • The vibration resistance of sensors was demonstrated. [ABSTRACT FROM AUTHOR]

Background: Clinical nurses are susceptible to compassion fatigue when exposed to various types of traumatic events in patients for extended periods of time. However, the developmental process, staging, and psychological responses distinct to each stage of compassion fatigue in nurses are not fully clarified. This study aimed to explore the processes of compassion fatigue and the psychological experiences specific to each phase of compassion fatigue among clinical nurses. Methods: Charmaz's Constructivist Grounded Theory methodology was used in this qualitative research. Semi-structured interviews were conducted with 13 clinical nurses with varying degrees of compassion fatigue from December 2020 to January 2021. Interview data were analyzed using grounded theory processes. Results: The data were categorized into five separate categories and 22 sub-categories. This study found that the process of compassion fatigue is dynamic and cumulative, which was classified into five phases: compassion experience period, compassion decrement period, compassion discomfort period, compassion distress period, and compassion fatigue period. Conclusion: Clinical nurses who experience compassion fatigue may go through five stages that are stage-specific and predictable. The findings can shed light on local and global applications to better understand the problem of nurses' compassion fatigue. The interventions for addressing compassion fatigue in clinical nurses should be stage-specific, targeted, and individualized. [ABSTRACT FROM AUTHOR]

Ecosystem water use efficiency (WUE) and ecosystem photosynthetic efficiency (EPE) are key indicators in studies of the carbon–water cycle in terrestrial ecosystems. Analyses of WUE and EPE can enhance our understanding of the relationship between ecosystem light use efficiency and WUE. Although several studies of individual indexes (i.e., either WUE or EPE) have been conducted, analyses of variation in both WUE and EPE, as well as their relationships, have rarely been conducted. Here, we analyzed spatial and temporal variation in WUE and EPE in Central Asia. Specifically, time trend analysis was conducted to characterize temporal and spatial changes in WUE and EPE in Central Asia from 2001 to 2020 at different altitudes and latitudes. Pearson correlation analysis was used to characterize the effects of precipitation and temperature on WUE and EPE. WUE decreased and EPE increased in Central Asia over the 20-year study period; this might have been due to interannual variations in precipitation and temperature. WUE was highest in August, and EPE was highest in June and July. Substantial spatial heterogeneity in WUE and EPE was observed; WUE was highly variable in Central Asia as well as in western and southern Central Asia. Major changes in EPE were observed in northern, eastern, and southern Central Asia. We also found that both WUE and EPE decreased with the increase in altitude. WUE was positively correlated with temperature and negatively correlated with precipitation, whereas EPE was positively correlated with both temperature and precipitation. The increase in photosynthetic efficiency might be one of the main factors contributing to increases in ecosystem productivity in arid environments. The temporal and spatial variation in WUE and EPE observed in our study will aid ecosystem research, providing a reliable theoretical basis for ecosystem research in areas with scarce large-scale data, integrated water resources management, and ecosystem restoration efforts. Our findings also enhance our understanding of the terrestrial carbon–water cycle and have implications for predicting ecosystem responses to climate change. The results of this study provide insights that will aid studies of the terrestrial carbon–water cycle under the background of climate change. It is of great significance to further study the carbon water cycle in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] Amidst the rapid advancements in experimental technology, noise-intermediate-scale quantum (NISQ) devices have become increasingly programmable, offering versatile opportunities to leverage quantum computational advantage. Here we explore the intricate dynamics of programmable NISQ devices for quantum reservoir computing. Using a genetic algorithm to configure the quantum reservoir dynamics, we systematically enhance the learning performance. Remarkably, a single configured quantum reservoir can simultaneously learn multiple tasks, including a synthetic oscillatory network of transcriptional regulators, chaotic motifs in gene regulatory networks, and the fractional-order Chua's circuit. Our configured quantum reservoir computing yields highly precise predictions for these learning tasks, outperforming classical reservoir computing. We also test the configured quantum reservoir computing in foreign exchange (FX) market applications and demonstrate its capability to capture the stochastic evolution of the exchange rates with significantly greater accuracy than classical reservoir computing approaches. Through comparison with classical reservoir computing, we highlight the unique role of quantum coherence in the quantum reservoir, which underpins its exceptional learning performance. Our findings suggest the exciting potential of configured quantum reservoir computing for exploiting the quantum computation power of NISQ devices in developing artificial general intelligence. [ABSTRACT FROM AUTHOR]

With the existing pressure sensors, it is difficult to achieve the unification of wide pressure response range and high sensitivity. Furthermore, the preparation of pressure sensors with excellent performance for sleep health monitoring has become a research difficulty. In this paper, based on material and microstructure synergistic enhancement mechanism, a hybrid pressure sensor (HPS) integrating triboelectric pressure sensor (TPS) and piezoelectric pressure sensor (PPS) is proposed. For the TPS, a simple, low-cost, and structurally controllable microstructure preparation method is proposed in order to investigate the effect of carbon nano-onions (CNOs) and hierarchical composite microstructures on the electrical properties of CNOs@Ecoflex. The PPS is used to broaden the pressure response range and reduce the pressure detection limit of HPS. It has been experimentally demonstrated that the HPS has a high sensitivity of 2.46 V/104 Pa (50–600 kPa) and a wide response range of up to 1200 kPa. Moreover, the HPS has a low detection limit (10 kPa), a high stability (over 100,000 cycles), and a fast response time. The sleep monitoring system constructed based on HPS shows remarkable performance in breathing state recognition and sleeping posture supervisory control, which will exhibit enormous potential in areas such as sleep health monitoring and potential disease prediction. [ABSTRACT FROM AUTHOR]

This study associated the liver proton density fat fraction (PDFF), measured by multi-echo Dixon (ME-Dixon) and breath-hold single-voxel high-speed T2-corrected multi-echo 1H magnetic resonance spectroscopy (HISTO) at 1.5 T, with serum biomarkers and liver fibrosis stages. This prospective study enrolled 75 patients suspected of liver fibrosis and scheduled for liver biopsy and 23 healthy participants with normal liver function. The participant underwent ME-Dixon and HISTO scanning. The agreement of PDFF measured by ME-Dixon (PDFF-D) and HISTO (PDFF-H) were compared. Correlations between PDFF and serum fat biomarkers (total cholesterol, triglyceride, and high- and low-density lipoproteins) and the liver fibrosis stages were assessed. PDFF were compared among the liver fibrosis stages (F0–F4) based on clinical liver biopsies. The Bland–Altman plot showed agreement between PDFF-D and PDFF-H(LoA, − 4.44 to 6.75), which have high consistency (ICC 0.752, P < 0.001). The correlations with the blood serum markers were mild to moderate (PDFF-H: r = 0.261–0.410, P < 0.01; PDFF-D: r = 0.265–0.367, P < 0.01). PDFF-D, PDFF-H, and steatosis were distributed similarly among the liver fibrosis stages. PDFF-H showed a slight negative correlation with the liver fibrosis stages (r = − 0.220, P = 0.04). Both ME-Dixon and HISTO sequences measured liver fat content noninvasively. Liver fat content was not directly associated with liver fibrosis stages. [ABSTRACT FROM AUTHOR]

Climate change forecasts indicate that the frequency and intensity of extreme climate events will increase in the future; these changes will have important effects on ecosystem stability and function. An important arid region of the world, Central Asia has ecosystems that are extremely vulnerable to extreme weather events. However, few studies have investigated the resistance and resilience of this region's ecosystems to extreme weather events. In this study, first, the extreme drought/wet threshold was calculated based on the 113-year (1901–2013) standardized precipitation–evapotranspiration index (SPEI); second, moderate resolution imaging spectroradiometer (MODIS) remote sensing data were applied to calculate ecosystem water use efficiency (WUE) and quantify ecosystem resistance and resilience after different extreme climate events; and finally, differences in the changes of various ecosystem types before and after climate events were assessed. The results showed the following: (1) The average SPEI was 0.073, and the thresholds of extreme wetness and drought were 0.91 and −0.67, respectively. Central Asia experienced extreme wet periods in 2002 and 2003 and a drought period in 2008. (2) Suitable wetness levels can increase the resistance of an ecosystem; however, continuous wetness reduces ecosystem resistance, as does drought. Wet areas had strong resilience after wet events, and arid areas had strong resilience after drought events. (3) During both wet and drought years, the transition between shrubland and grassland caused changes in ecosystem resistance and resilience. These findings are important for understanding the impact of future climate change on ecosystem stability. [ABSTRACT FROM AUTHOR]

Mixed-potential type ammonia sensors based on yttria-stabilized zirconia are promising devices in NOx reducing system for high-temperature exhaust. However, selectivity is a critical issue that should be urgently addressed. Herein, a novel bilayer Cr2O3|In2O3 sensing electrode (SE) was designed to improve the selectivity of the ammonia sensor, in which an additional Cr2O3 layer was deposited on In2O3 SE. The selectivity was examined in NH3, CO, NO and NO2. Finally, the sensor with the bilayer Cr2O3|In2O3 SE exhibits an improvement of NH3 selectivity at 600 °C, which is attributed to the Cr2O3 layer catalysing the removal of CO and NOx before the gases reach the triple-phase boundaries (TPBs). Furthermore, the mixed-potential model of the NH3 sensor with the bilayer SE was identified using the polarization curves obtained in different concentrations of NH3. Additionally, the proposed sensor displayed a good repeatability and resistances to CO2 and H2O. This innovative bilayer Cr2O3|In2O3 SE is expected to be applied in high-temperature NH3 detection. [ABSTRACT FROM AUTHOR]

A one-step strategy for synthesizing fluorescent copper clusters stabilized by L -cysteine has been successfully established in aqueous solutions. The direct determination of copper ions was realized by the fluorescence enhancement phenomenon caused by the preparation and aggregation process. At the same time, ammonia treatment can lead to rapid fluorescence quenching, resulting from the influence on the aggregation behavior of Cu clusters, while the fluorescence can be recovered by the continuous addition of copper ions. Therefore, a recyclable fluorescence sensing system is constructed for the simultaneous determination of copper ions and ammonia. This method is simple, anti-interference and has been successfully applied to the determination of environmental samples. [ABSTRACT FROM AUTHOR]

Drought appears at flowering and boll formation for cotton frequently. However, reports on the impact of carbon dynamics in the subtending leaf on boll biomass under periodic droughts are limited. To investigate this, experiments were carried out with two cultivars (drought‐tolerant: Dexiamian 1; drought‐sensitive: Yuzaomian 9110), three water levels [soil relative water content (SRWC): control (75 ± 5)%, moderate drought (60 ± 5)%, severe drought (45 ± 5)%] and five drought durations (10, 17, 24, 31 and 38 days). A 38‐day drought declined the net photosynthetic rate of subtending leaf, which could be collectively attributed to the reduction in carboxylation with reduced ribulose‐1,5‐bisphosphate carboxylase activity, and stomal limitation with decreased stomatal conductance, along with the damage of photosynthetic apparatus with depressed maximum and actual photochemical quantum yield, leading to lower starch content. A 38‐day drought also increased the activities of sucrose phosphate synthase (SPS), sucrose synthase (Susy) and expressions of genes (GhSPS1, GhSPS2, GhSusA and GhSusB) associated with these enzymes, causing the accumulation of sucrose content, finally resulting in lower boll biomass. Some of the above parameters fully recovered under more than 17‐day moderate drought or over 10‐day severe drought, but boll biomass still decreased after re‐watering. Under 10‐day moderate drought, all aforementioned indices and boll biomass were completely recovered within 7 days of re‐watering, and the recovery capacity of Yuzaomian 9110 was lower than that of Dexiamian 1. Therefore, rapid recovery of photosynthesis and decline in the subtending leaf sucrose content to pre‐stress levels are important factors in lessening the impacts of drought on boll biomass and are indicative of cultivar tolerance to short‐term moderate water deficit. [ABSTRACT FROM AUTHOR]

Deep Reinforcement Learning (DRL) algorithms have been increasingly used to construct stock trading strategies, but they often face performance challenges when applied to financial data with low signal-to-noise ratios and unevenness, as these methods were originally designed for the gaming community. To address this issue, we propose a DRL-based stock trading system that leverages Cascaded Long Short-Term Memory (CLSTM-PPO Model) to capture the hidden information in the daily stock data. Our model adopts a cascaded structure with two stages of carefully designed deep LSTM networks: it uses one LSTM to extract the time-series features from a sequence of daily stock data in the first stage, and then the features extracted are fed to the agent in the reinforcement learning algorithm for training, while the actor and the critic in the agent also use a LSTM network. We conduct experiments on stock market datasets from four major indices: the Dow Jones Industrial index (DJI) in the US, the Shanghai Stock Exchange 50 (SSE50) in China, S&P BSE Sensex Index (SENSEX) in India, and the Financial Times Stock Exchange 100 (FTSE100) in the UK. We compare our model with several benchmark models, including: (i) a model based on a buy-and-hold strategy; (ii) a Proximal Policy Optimization (PPO) model with Multilayer Perceptron (MLP) policy; (iii) some up-to-date models like the MLP model, LSTM model, Light Gradient Boosting Machine (LGBM) model, and histogram-based gradient boosting model; and (iv) an ensemble strategy model. The experimental results show that our model outperforms the baseline models in several key metrics, such as cumulative returns, maximum earning rate, and average profitability per trade. The improvements range from 5% to 52%, depending on the metric and the stock index. This indicates that our proposed method is a promising way to build an automated stock trading system. [ABSTRACT FROM AUTHOR]

SUMMARY: Drought stress significantly affects cotton's net photosynthetic rate (A) by restraining stomatal (gs) and mesophyll conductance (gm) as well as perturbing its biochemical process, resulting in yield reductions. Despite the significant progress in dissecting effects of drought on photosynthesis, the variability observed in cotton's gm, and the mechanisms contributing to that variability under dynamic drought stress conditions are poorly understood. For that reason, a controlled‐environment experiment with two cotton genotypes (Dexiamian 1, Yuzaomian 9110), three water levels (soil relative water content: control [75 ± 5]%, moderate drought [60 ± 5]%, severe drought [45 ± 5]%), and two drought durations (10 and 31 days) were conducted. The results indicated that the cotton boll biomass was significantly decreased under 10‐day severe drought and 31‐day moderate and severe drought. Decreases in gs were later accompanied by decreases in gm and further combined with reductions in electron transport rate, as drought stress progressed in duration and severity, ultimately resulting in significant reductions in A of subtending leaf. Stomatal and mesophyll conductance constraints were the primary factors limiting photosynthesis, while biochemical constraints decreased, as drought stress progressed. Considering gm, its decline was ascribed to increases in the diffusion resistance of CO2 through cytoplasm (rcyt), under short‐ or long‐term drought, as well as to increases in leaf dry mass (LMA), and decreases in the chloroplast surface area exposed to intercellular air space (Sc/S), under long‐term drought. It was concluded that A could be enhanced, under dynamic drought stress conditions, by increasing gm through increasing Sc/S and reducing LMA and rcyt. [ABSTRACT FROM AUTHOR]

We report herein a series of quinoline-4-carboxylic acid linked COFs via the multicomponent one-pot in situ Doebner reaction. The obtained acid–base bifunctional COFs are chemically stable and can highly promote one-pot cascade deacetalization–Knoevenagel condensation reaction in a heterogeneous way under solvent-free conditions. [ABSTRACT FROM AUTHOR]

Introduction: Newborn screening is an important supplement to thalassemia control and prevention. Capillary electrophoresis (CE) technology has several advantages for thalassemia screening but with low sensitivity, especially for thalassemia carriers. This study aims to illustrate the application of an optimized interpretation model in newborn thalassemia screening by capillary hemoglobin electrophoresis. Methods: Two thousand, two hundred fifty‐eight neonates selected from four regions in China were enrolled and were screened for α‐thalassemia and β‐thalassemia by capillary electrophoresis. Results were interpreted based on an optimized model integrated with multiple parameters. Molecular analysis was carried out in synchrony and used as the gold standard for the screening performance assessment. The consistency among different regions and thalassemia genotypes were also investigated. Results: Among the 2258 neonates, 485 were identified to have a likely diagnosis of thalassemia, and 422 α‐thalassemia, 80 β‐thalassemia, and 21 α/β‐thalassemia cases were confirmed by molecular analysis, including 277 α‐thalassemia silent carriers, 135 α‐thalassemia trait carriers, 10 Hemoglobin H disease, and 80 β‐thalassemia trait carriers. The screening sensitivity, specificity, positive, and negative predictive value for α‐thalassemia and β‐thalassemia were 84.83%, 99.14%, 95.98%, 96.41%, and 88.75%, 98.73%, 76.34%, and 99.48%, respectively. The optimized interpretation model showed higher performance for thalassemia carriers, though some neonates with silent α‐thalassemia genotypes (‐α3.7/αα, ‐α4.2/αα, and αWSα/αα) and β‐28/βN genotype were still missed. The screening performance among different regions was comparable. Conclusions: Capillary hemoglobin electrophoresis with the optimized interpretation model shows reliable performance for newborn thalassemia screening. It is applicable to large‐scale population screening. [ABSTRACT FROM AUTHOR]

Selective catalytic reduction (SCR) utilizing urea hydrolysis to generate ammonia (NH 3) is the most efficient technology to reduce the emission of nitrogen oxides (NO x). NH 3 detection is crucial in the closed-loop feedback system for the precise urea injection. In this work, a high-temperature NH 3 sensor using a BaZr 0.8 Y 0.2 O 3-δ (BZY) proton conductor as the electrolyte and a BaCo 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3-δ (BCFZY) H+/e–/O2– triple conductor as the sensing electrode (SE) is reported. The effect of the micromorphology of the BCFZY SE on the sensing performance is investigated by varying the sintering temperature of SE. The sensor shows high sensitivity to NH 3 with response currents of 0.39, 1.31, 3.03, and 1.81 μA/ppm at 350, 400, 450, and 500 °C, respectively. Furthermore, the sensor shows excellent selectivity and repeatability. This work demonstrates that the BCFZY-based sensor has great potential for the high-temperature NH 3 detection. • BaCo 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3-δ triple conductor was used as the sensing electrode for ammonia detection. • A novel ammonia sensor was proposed based on the BZY proton electrolyte. • The influence of the morphology of BCFZY on the sensing performance was investigated. [ABSTRACT FROM AUTHOR]

We have developed a finite element model to simulate the penetration of nanoneedles into the cellular nucleus. It is found that the nuclear lamina, the primary supporting structure of the nuclear membrane, plays a crucial role in maintaining the integrity of the nuclear envelope and enhancing stress concentration in the nuclear membrane. Notably, nuclear lamina A exhibits a more pronounced effect compared to nuclear lamina B. Subsequently, we further conducted experiments by controlling the time of osteopontin (OPN) treatment to modify the nuclear lamina density, and the results showed that an increase in nuclear lamina density enhances the probability of nanoneedle penetration into the nuclear membrane. Through employing both simulation and experimental techniques, we have gathered compelling evidence indicating that an augmented density of nuclear lamina A can enhance the penetration of nanoneedles into the nuclear membrane. [ABSTRACT FROM AUTHOR]

• Discuss the ideal focal species from the perspective of habitat preference. • Explore wading birds' substitute potential to represent broader bird biodiversity. • Consider habitat preference in both ecological source selection and resistance surface design. • The EN4 for wading birds is the most cost-effective and potentially fits all birds. • The ES4 exhibits a remarkable overlap with the ECR and PBF. Focal species play a crucial role in planning ecological networks (ENs). Despite the finding that ENs designed for a specific focal species can yield benefits for associated communities, current practices of applying individual focal species have faced criticism for oversimplifying intricate ecosystems. Besides, the aggregation of ENs for individual species has been demonstrated as ineffective and costly. To improve cost-effectiveness, species with similar habitat preferences are typically conserved using shared strategies. Thus, drawing from the habitat preference of wading birds for blue and green spaces, we hypothesized that an EN for wading birds may benefit co-existing water and forest birds that prefer blue or green spaces. To validate this hypothesis, we conducted our study in the Yangtze River Delta's Ecological Green Integration Demonstration Zone. We simulated six scenarios S1-S6 to compare the cost-effectiveness of focal species networks, respectively for water, forest, and wading birds in the S2-S4, with the aggregate networks in the S5-S6. During ENs' construction, we employed the InVEST Habitat Quality model, MSPA, MCR model, and Linkage Mapper Tools. Furthermore, we selected the most cost-effective EN by calculating six ENs' connectivity-cost ratio (CCr index) and ranked the conservation priority for its sources and corridors. The results showed that the EN4 ranked highest in the CCr index and displayed a high conservation efficiency for all bird species. 93.41% of primary ES4 and 42.46% of secondary ES4 overlapped with the ecological conservation redline and the permanent basic farmland and could be well protected under current statutory planning. Our findings confirm that wading birds are the ideal focal species in EN planning for broader bird conservation in the context of the Yangtze River Delta. The constructed regional EN could contribute to establishing a linkage with the supra-regional EN and the world's major bird migration flyway. Moreover, our cost-effective approach to bird conservation could provide new insights for targeting focal species from the perspective of habitat preference in multi-species EN planning. [ABSTRACT FROM AUTHOR]

Background: Docetaxel (DTX) exhibits antitumor effects against breast cancer by stabilizing microtubules and increasing the accumulation of reactive oxygen species (ROS). DTX extravasation during infusion often causes skin injury. The present study aimed to investigate the effects and mechanisms of icaritin (ICT) on DTX‐induced skin injury. Methods: The effects of ICT on the viability and apoptosis of HaCaT cells were measured by SRB assay and flow cytometry, respectively. Endogenous LC3 puncta and microtubules were determined by immunofluorescence. The number of mitochondria was measured by MitoTracker orange staining. ROS were determined by dihydroethidium staining. The expression of markers of ROS and autophagy were measured by western blotting. Chloroquine, compound D, and tamoxifen were employed as the inhibitor for autophagy and AMPK, estrogen receptors (ERs) modulator, respectively. Results: DTX inhibited the viability and decreased apoptosis of HaCaT cells, which can be rescued by ICT. ICT decreased microtubule bundles, increased the number of mitochondria, and attenuated ROS of HaCaT cells induced by DTX. ICT blocks autophagy and the autophagic flux. Compound C or tamoxifen diminished the protection effects of ICT on DTX‐treated HaCaT cells. Conclusion: ICT alleviates DTX‐induced skin injury by suppressing ROS, reducing microtubule bundles, and blocking autophagy via ERs. Our study indicated that ICT may be a potential candidate for DTX‐induced skin injury. [ABSTRACT FROM AUTHOR]

We inoculated Tuber aestivum and Tuber sinoaestivum on Carya illinoinensis to explore the effects of inoculation on host plant growth, enzyme activities, the physicochemical properties of rhizosphere soil, the denitrifying bacterial community in the rhizosphere, and the distribution of mating type genes in the rhizosphere. We found that the Tuber spp. inoculation increased the height of the host plant and that the stem circumference of the host was greater two months after inoculation. Six months after inoculation, the peroxidase activity of the seedlings inoculated with T. sinoaestivum was higher than that of the control. At four and six months after inoculation, the superoxidase dismutase activities of the seedlings inoculated with T. aestivum were higher than those of the seedlings inoculated with T. sinoaestivum. Six months after inoculation, nitrate nitrogen content was lowest in the control and highest in the T. sinoaestivum treatment. Among the nirS -type denitrifying bacteria community, the relative abundances of Proteobacteria were high. T. aestivum and T. sinoaestivum inoculation did not affect the diversity of denitrifying bacteria. The mating type genes MAT1-1-1 and MAT1-2-1 were detected in the rhizosphere of C. illinoinensis inoculated with T. sinoaestivum and T. aestivum , and MAT1-1-1 dominated over MAT1-2-1. [ABSTRACT FROM AUTHOR]

The mechanical properties of WC-6Co cemented carbides with different contents of graphene oxide (GO)/nanoalumina (Al 2 O 3) composite particles were investigated. The results showed that some of the GO/Al 2 O 3 composite particles were tightly wrapped in WC grains through boundary deformation, but some of them existed in the cobalt phase, which gradually decreased the cobalt phase lattice constant and caused different degrees of grain refinement. When the content was 0.05 wt%, the cobalt phase dissolved more W; thus, the solid solution strengthening effect was improved. In addition, the superior dispersion of the composite particles aided in particle refinement. The relative alloy density increased as the GO/Al 2 O 3 composite particle content increased. The mechanical properties first increased and then decreased with increasing additive amounts. When the content was 0.05 wt%, the alloy had the best performance. The hardness was 2021 HV 30 , the strength was 2480.4 MPa, and the toughness was 11.5 MPa⋅m1/2. [ABSTRACT FROM AUTHOR]

The present study aimed to analyse the frequencies of human leukocyte antigen HLA‐ABCDQB1 and HLA‐DRB1 alleles and haplotypes in a subset of 3,732 Han population from Hubei of China. All samples were typed in the HLA‐ABCDQB1 and HLA‐DRB1 loci using the sequence‐based typing method; subsequently, the HLA polymorphisms were analysed. A total of 47 HLA‐A, 89 HLA‐B, 43 HLA‐C, 49 HLA‐DRB1 and 24 HLA‐DQB1 alleles were identified in the Hubei Han population. The top three most frequent alleles in the HLA‐ABCDQB1 and HLA‐DRB1 were A*11:01 (0.2617), A*24:02 (0.1590), A*02:07 (0.1281); B*46:01 (0.1502), B*40:01 (0.1409) and B*58:01 (0.0616); C*01:02 (0.2023), C*07:02 (0.1691) and C*03:04 (0.1175); and DQB1*03:01 (0.2000), DQB1*03:03 (0.1900), DQB1*06:01 (0.1187); DRB1*09:01 (0.1790), DRB1*15:01 (0.1062) and DRB1*12:02 (0.0841), respectively. Meanwhile, the three most frequent two‐loci haplotypes were A*02:07‐C*01:02 (0.0929), B*46:01‐C*01:02 (0.1366) and DQB1*03:03‐DRB1*09:01 (0.1766). The three most frequent three‐loci haplotypes were A*02:07‐B*46:01‐C*01:02 (0.0883), B*46:01‐DQB1*03:03‐DRB1*09:01 (0.0808) and C*01:02‐DQB1*03:03‐DRB1*09:01 (0.0837). The three most frequent four‐loci haplotypes were A*02:07‐B*46:01‐C*01:02‐DQB1*03:03 (0.0494), B*46:01‐DRB1*09:01‐C*01:02‐DQB1*03:03 (0.0729) and A*02:07‐B*46:01‐DQB1*03:03‐DRB1*09:01 (0.0501). The most frequent five‐loci haplotype was A*02:07‐B*46:01‐C*01:02‐DQB1*03:03‐DRB1*09:01 (0.0487). Heat maps and multiple correspondence analysis based on the frequencies of HLA specificity indicated that the Hubei Han population might be described into Southern Chinese populations. Our results lay a certain foundation for future population studies, disease association studies and donor recruitment strategies. [ABSTRACT FROM AUTHOR]

Yttrium-doped BaZrO 3 (BZY) shows great potential as a new solid electrolyte for high-temperature NH 3 sensing applications. However, it is difficult to obtain a dense BZY electrolyte due to the refractory nature of this material. For this paper, an amperometric NH 3 sensor based on a BaZr 0.8 Y 0.2 O 3-δ (BZY20) electrolyte was proposed, and volatile B 2 O 3 was added to improve the density of BZY, which was essential to enhance the sensitivity and stability of the sensor. The effects of B 2 O 3 on the density, morphology, and conductivity of the electrolyte were investigated. Furthermore, the influence of the density of BZY20 on the sensitivity and stability of the sensor was analyzed. It was found that the sensitivity and stability were significantly improved by the enhancement of the conductivity. In addition, the sensor could reach a detection limit as low as 2.5 ppm for NH 3 at 450 ℃ and showed good selectivity, repeatability, and long-term stability. [Display omitted] • An NH 3 sensor was studied based on a dense BaZr 0.8 Y 0.2 O 3-δ electrolyte using volatile B 2 O 3 as a sintering additive. • The stability and sensing performance of the sensor improved with an increase in the density of BZY20. • The sensing mechanism and stability of the dense BZY20-based NH 3 sensor was analyzed by EIS. [ABSTRACT FROM AUTHOR]

Owing to their permanent porosity, highly ordered and extended structure, good chemical stability, and tunability, covalent organic frameworks (COFs) have emerged as a new type of organic materials that can offer various applications in different fields. Benefiting from the huge database of organic reactions, the required functionality of COFs can be readily achieved by modification of the corresponding organic functional groups on either polymerizable monomers or established COF frameworks. This striking feature allows homochiral covalent organic frameworks (HCCOFs) to be reasonably designed and synthesized, as well as their use as a unique platform to fabricate asymmetric catalysts. This contribution provides an overview of new progress in HCCOF‐based asymmetric catalysis, including design, synthesis, and their application in asymmetric organic synthesis. Moreover, major challenges and developing trends in this field are also discussed. It is anticipated that this review article will provide some new insights into HCCOFs for heterogeneous asymmetric catalysis and help to encourage further contributions in this young but promising field. [ABSTRACT FROM AUTHOR]

Recent efforts in biomedical visual question answering (VQA) research rely on combined information gathered from the image content and surrounding text supporting the figure. Biomedical journals are a rich source of information for such multimodal content indexing. For multipanel figures in these journals, it is critical to develop automatic figure panel splitting and label recognition algorithms to associate individual panels with text metadata in the figure caption and the body of the article. Challenges in this task include large variations in figure panel layout, label location, size, contrast to background, and so on. In this work, we propose a deep convolutional neural network, which splits the panels and recognizes the panel labels in a single step. Visual features are extracted from several layers at various depths of the backbone neural network and organized to form a feature pyramid. These features are fed into classification and regression networks to generate candidates of panels and their labels. These candidates are merged to create the final panel segmentation result through a beam search algorithm. We evaluated the proposed algorithm on the ImageCLEF data set and achieved better performance than the results reported in the literature. In order to thoroughly investigate the proposed algorithm, we also collected and annotated our own data set of 10,642 figures. The experiments, trained on 9,642 figures and evaluated on the remaining 1,000 figures, show that combining panel splitting and panel label recognition mutually benefit each other. [ABSTRACT FROM AUTHOR]

Both labeled and unlabeled data have been widely used in electroencephalographic (EEG)-based brain-computer interface (BCI). However, labeled EEG samples are generally scarce and expensive to collect, while unlabeled samples are considered to be abundant in real applications. Although the semi-supervised learning (SSL) allows us to utilize both labeled and unlabeled data to improve the classification performance as against supervised algorithms, it has been reported that unlabeled data occasionally undermine the performance of SSL in some cases. To overcome this challenge, we propose a collaborative representation-based semi-supervised extreme learning machine (CR-SSELM) algorithm to evaluate the risk of unlabeled samples by a new safety-control mechanism. Specifically, the ELM model is firstly used to predict unlabeled samples and then the collaborative representation (CR) approach is employed to reconstruct the unlabeled samples according to the obtained prediction results, from which the risk degree of unlabeled sample is defined. A risk-based regularization term is then constructed accordingly and embedded into the objective function of the SS-ELM. Experiments conducted on benchmark and EEG datasets demonstrate that the proposed method outperforms the ELM and SS-ELM algorithm. Moreover, the proposed CR-SSELM even offers the best performance while SS-ELM yields worse performance compared with its supervised counterpart (ELM). [ABSTRACT FROM AUTHOR]

This study lays a foundation for the design of the SH0 plate acoustic wave (PAW) resonators based on LiNbO3 plate, and are applicable to the ultra-wideband filters and next-generation tunable filters. The coupling coefficient ($k^{2}$) of SH0 mode is optimized to as high as 55% and wideband spurious are well controlled by analyzing the propagation characteristics of plate modes in LiNbO3. The SH0 mode is demonstrated to be slowly dispersive and features the superiority of interdigital transducer (IDT)—defining frequency over most other plate modes. On the device level, the transducer types and electrode materials are investigated and compared. In addition, for edge-reflected SH0 resonators, stopband dispersion analysis is provided and the longitudinal ripples are suppressed. For edge-reflected SH0 resonators, a novel perfect edge reflector is proposed with elimination of longitudinal spurious ripples. [ABSTRACT FROM AUTHOR]

A concept for the development of spectrum-clean S1 Lamb wave resonator (LWR) utilizing an aluminum nitride (AlN) plate with damped edge reflectors is demonstrated. Numerical analysis is performed on the dispersive characteristics of the Lamb modes propagating in AlN plates, and the design parameters to enable zero group velocity (vg) for the S1 mode are identified. The simulation results based on finite element analysis verify that the use of the damped edge reflectors, instead of the conventional edge reflectors, can efficiently de-couple most of the Lamb waves such as the S0 mode by mode conversion upon edges, but not the S1 mode characterizing zero vg. Specifically, the measured frequency response of a 1.38-GHz AlN S1 LWR with damped edge reflectors yields a clean spectrum up to 6 GHz and excellent resonance passband performance. [ABSTRACT FROM AUTHOR]

Microfibers with a core-shell structure can be produced by co-axial electrospinning, allowing for the functionalization of the outer layer with bioactive molecules. In this study, a thermoplastic, degradable polyesteretherurethane (PEEU), consisting of poly(p-dioxanone) (PPDO) and poly(ɛ-caprolactone) (PCL) segments with different PPDO to PCL weight ratios, were processed into fiber meshes by co-axial electrospinning with gelatin. The prepared PEEU fibers have a diameter of 1.3±0.5 μm and an elastic modulus of around 5.1±1.0 MPa as measured by tensile testing in a dry state at 37°C, while the PEEU/Gelatin core-shell fibers with a gelatin content of 12±6 wt% and a diameter of 1.5±0.5 μm possess an elastic modulus of 15.0±1.1 MPa in a dry state at 37 °C but as low as 0.7±0.7 MPa when hydrated at 37 °C. Co-axial electrospinning allowed for the homogeneous distribution of the gelatin shell along the whole microfiber. Gelatin with conjugated Fluorescein (FITC) remained stable on the PEEU fibers after 7 days incubation in Phosphate-buffered saline (PBS) at 37 °C. The gelatin coating on PEEU fibers lead to enhanced human adipose tissue derived mesenchymal stem cell (hADSC) attachment and a proliferation rate 81.7±34.1 % higher in cell number in PEEU50/Gelatin fibers after 7 days of cell culture when compared to PEEU fibers without coating. In this work, we demonstrate that water-soluble gelatin can be incorporated as the outer shell of a polymer fiber via molecular entanglement, with a sustained presence and role in enhancing stem cell attachment and proliferation. [ABSTRACT FROM AUTHOR]

Laminin-5 (Ln-5), an important extracellular matrix (ECM) protein, plays a critical role in regulating the growth and differentiation of mesodermal tissues, including bone. Ln-5 can be secreted by the mesenchymal stem cells (MSCs), and Ln-5 promotes MSCs osteogenic differentiation. It has been demonstrated that a substrate's surface topography could regulate MSC secretion and differentiation. A better understanding of the mechanism of how Ln-5 and surface roughness regulate MSC osteogenic differentiation would guide the design of surface topography and coatings of orthopedic implants and cell culture substrates. However, few studies have investigated the relationship between surface roughness and the secretion of Ln-5 in MSC osteogenic differentiation. Whether substrate surface topography regulates MSC differentiation via regulating Ln-5 secretion and how surface topography contributes to the secretion of Ln-5 are still not known. In this study, the influence of microscale roughness at different levels (R0, R1 and R2) on the secretion of Ln-5 of human bone marrow MSCs (hBMSCs) and subsequent osteogenic differentiation were examined. hBMSCs spreading, distribution and morphology were greatly affected by different roughness levels. A significantly higher level of Ln-5 secretion was detected on R2, which correlated to the local cell density regulated by the rough surface. Ln-5 binding integrins (α2 and α3) were strongly activated on R2. In addition, the results from hBMSCs on R0 inserts with different cell densities further confirmed that local cell density regulated Ln-5 secretion and cell surface integrin activation. In addition, the mineralization level of MSCs on R2 was remarkably higher than that on R0 and R1. These results suggest that hBMSC osteogenic differentiation level on R2 roughness was enhanced via increased Ln-5 secretion that was attributed to rough surface regulated local cell density. Thus, the microroughness could serve as effective topographical stimulus in cell culture devices and bone implant materials. [ABSTRACT FROM AUTHOR]

We report a detailed theoretical modeling of lattice thermal conductivity in nanoscale AlN/GaN/AlN heterostructures. Thermal conductivity in such heterostructures is derived based on the solution of the phonon Boltzmann equation in the relaxation-time approximation. Phonon dispersion relations are obtained in the elastic continuum approximation using the finite-difference numerical method. Quasi-two-dimensional (2D) phonon density of states is derived using the actual phonon dispersion. To investigate the effects of partial phonon spatial confinement, numerical simulations are performed for both the three-layer heterostructures and the single GaN thin films. The dependence of the thermal conductivity on the core or cladding layer thickness in an AlN/GaN/AlN heterostructure is also discussed. We have demonstrated that partial phonon confinement leads to a higher thermal conductivity in an AlN/GaN/AlN heterostructure than that in a single GaN thin film with the same total structure thickness. Such thermal conductivity can also be tuned higher or lower by adjusting the core or cladding layer thickness without changing the total thickness of the structure. Obtained results have quantitatively shown that it is possible to improve heat conduction in semiconductor nanostructures through phonon spectrum engineering, in agreement with other recent studies. [ABSTRACT FROM AUTHOR]

The effects of synchronous variations of influent salinity with the elevation of NH 4 +-N concentration on nitrification performance and microbial community structure of bioreactor are often ignored. In this study, we investigated the dynamic response of nitrifying activated sludge to synchronously increased salinity and ammonia loading rate (ALR) in a nitrification membrane bioreactor (MBR). We found that the increase in influent salinity above 1% (from 0.91 to 1.32%) led to the deterioration of the nitrification performance of the MBR. The combined inhibition effect of salinity (1.32%), free ammonia (FA, an average of 1.37 mg/L), and free nitrous acid (FNA, an average of 0.155 mg/L) on nitrite-oxidizing bacteria (NOB) resulted in long-term (35 days) nitrite accumulation. The further increase of salinity and ALR exhibited little influence on the nitrification performance of MBR after the activated sludge had adapted to high salinity (>1%), effective nitrification performance was achieved at high ALR up to 1.71 kg NH 4 +-N/m3·d and high salinity (2.13%). The microbial analysis showed that the elevated salinity and accumulation of FNA reshaped the microbial community structure of ammonia-oxidizing bacteria (AOB) and NOB. The dominant species of AOB and NOB shifted from the salinity-resistant species Nitrosomonas aestuarii to the species Nitrosomonas mobilis with dual resistant to salinity and FNA, and from non-salinity-resistant species Candidatus Nitrospira defluvii to salinity-resistant species Nitrobacter winogradskyi and Nitrospira marina , respectively. Therefore, the salinity of 1% may be a critical level for the nitrification performance and the shift in the nitrifier community of activated sludge without salinity acclimation. [Display omitted] • The elevation of salinity above 1% deteriorated the nitrification performance. • The elevation of salinity above 1% reshaped the nitrifier community. • The dominant AOB shifted from Nitrosomonas aestuarii to Nitrosomonas mobilis. • Nitrobacter winogradskyi and Nitrospira marina are predominant NOB at high salinity. [ABSTRACT FROM AUTHOR]

Pt nanoparticle (PtNP)-modified La 0.8 Sr 0.2 MnO 3 (LSM)-sensing electrodes (SE) were developed successfully by the impregnation method for amperometric total NO X (NO and NO 2) sensors. The structure, morphology, and surface valence state of SE were characterized by thermogravimetry (TG), X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The results showed that all SEs of the sensors were uniformly modified with PtNPs; interestingly, the size of the PtNPs increased with an increase in the modified content. Compared with pure LSM, the sensor based on 0.50 vol% Pt/LSM exhibited enhanced gas-sensing properties toward total NO X. The sensitivity improved from − 9.04 to − 18.7 μA/decade in the NO X , ranging from 50 ppm to 800 ppm. Moreover, the sensor maintained a 94% response signal after a long-term stability test, showing a stable response during the long-term thermal cycling test towards total NO X. Meanwhile, the sensor exhibited markable selectivity and consistency. The catalytic effect of Pt nanoparticles was believed to be the main reason for the enhancement of gas-sensing characteristics. • A total NO X amperometric sensor was achieved through modification with PtNPs on the La 0.8 Sr 0.2 MnO 3 sensing electrode. • PtNP agglomeration was quantified using SEM images and software. • The influence of Pt nanoparticles (PtNPs) on sensing performance was evaluated, and the sensing process was analyzed. [ABSTRACT FROM AUTHOR]

A model for phonon heat conduction in a semiconductor nanowire with dimensions comparable to the phonon mean free path is developed. It is based on the solution of Boltzmann's equation, which takes into account (i) modification of the acoustic phonon dispersion due to spatial confinement, and (ii) change in the nonequilibrium phonon distribution due to partially diffuse boundary scattering. Numerical simulation is performed for a silicon nanowire with boundaries characterized by different interface roughness. Phonon confinement and boundary scattering lead to a significant decrease of the lattice thermal conductivity. The value of this decrease and its interface roughness and temperature dependence are different from the predictions of the early models. The observed change in thermal resistance has to be taken into account in simulation of deep-submicron and nanometer-scale devices. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Estimates of clumping index (Ω) are required to improve the indirect estimation of leaf area index (L) from optical field-based instruments such as digital hemispherical photography (DHP). A widely used method allows estimation of Ω from DHP using simple gap fraction averaging formulas (LX). This method is simple and effective but has the disadvantage of being sensitive to the spatial scale (i.e., the azimuth segment size in DHP) used for averaging and canopy density. In this study, we propose a new method to estimate Ω (LXG) based on ordered weighted gap fraction averaging (OWA) formulas, which addresses the disadvantages of LX and also accounts for gap size distribution. The new method was tested in 11 broadleaved forest stands in Italy; Ω estimated from LXG was compared with other commonly used clumping correction methods (LX, CC, and CLX). Results showed that LXG yielded more accurate Ω estimates, which were also more correlated with the values obtained from the gap size distribution methods (CC and CLX) than Ω obtained from LX. Leaf area index estimates, adjusted by LXG, are only 5%–6% lower than direct measurements obtained from litter traps, while other commonly used clumping correction methods yielded more underestimation. [ABSTRACT FROM AUTHOR]

Type 1 diabetes (T1D) is an autoimmune disease in which cells of the immune system destroy pancreatic β cells, which secrete insulin. The high prevalence of T1D in developed societies may be explained by environmental changes, including lower exposure to helminths. Indeed, infection by helminths such as Schistosoma, Filaria, and Heligmosomoides polygyrus and their by-products has been reported to ameliorate or prevent the development of T1D in human and animal models. Helminths can trigger distinct immune regulatory pathways, often involving adaptive immune cells that include T helper 2 (Th2) cells and regulatory T cells (Tregs) and innate immune cells that include dendritic cells, macrophages, and invariant natural killer T cells, which may act synergistically to induce Tregs in a Toll-like receptor-dependent manner. Cytokines such as interleukin (IL)-4, IL-10, and transforming growth factor (TGF)-β also play an important role in protection from T1D. Herein, we provide a comprehensive review of the effects and mechanisms underlying protection against T1D by helminths. [ABSTRACT FROM AUTHOR]

Lipid-containing adipocytes can dedifferentiate into fibroblast-like cells under appropriate culture conditions, which are known as dedifferentiated fat (DFAT) cells. However, the relative low dedifferentiation efficiency with the established protocols limit their widespread applications. In this study, we found that adipocyte dedifferentiation could be promoted via periodic exposure to cold (10°C) in vitro. The lipid droplets in mature adipocytes were reduced by culturing the cells in periodic cooling/heating cycles (10–37°C) for one week. The periodic temperature change led to the down-regulation of the adipogenic genes (FABP4, Leptin) and up-regulation of the mitochondrial uncoupling related genes (UCP1, PGC-1α, and PRDM16). In addition, the enhanced expression of the cell proliferation marker Ki67 was observed in the dedifferentiated fibroblast-like cells after periodic exposure to cold, as compared to the cells cultured in 37°C. Our in vitro model provides a simple and effective approach to promote lipolysis and can be used to improve the dedifferentiation efficiency of adipocytes towards multipotent DFAT cells. [ABSTRACT FROM AUTHOR]

The characteristics of the multi-mode resonance behavior of AlN Lamb wave resonators (LWRs) are theoretically and experimentally investigated for the first time in this paper. Adler’s approach and finite element method (FEM) are used to calculate the dispersive characteristics of the phase velocity ($v_{p}$), group velocity ($v_{g}$), effective coupling coefficient ($k^{2}_{\text {eff}}$), and temperature coefficient of frequency for the first eight Lamb wave modes with different transducer configurations. The FEM is performed to take an insight into the mode shapes of the S0mode and S1mode specifically: the S0mode is more contour-like and exhibits the largest $k^{2}_{\text {eff}}$ when $h_{\text {AlN}}/\lambda $ is close to 0.5; the S1mode is strong in vertical direction and can enable high resonance frequency ($f_{s}$) and large $k^{2}$ simultaneously when AlN thickness is very thin. Experimentally, AlN LWRs with different AlN thicknesses are designed and fabricated. The measured results are fitted into the multi-resonance BVD model so that the device performance parameters, as well as the equivalent, lumped element values are extracted and compared. By choosing different normalized AlN thicknesses, the performance of different Lamb wave modes varies largely due to the dispersive characteristics and agrees well with theoretically predicted acoustic characteristics. This paper lays the foundation for characterizing the multi-resonance behaviors of AlN LWRs and gives guidance on choosing the optimal design parameters and Lamb wave modes for different applications. [2018-0040] [ABSTRACT FROM AUTHOR]

Abstract Shale gas is becoming increasingly important to mitigate the energy crisis of the world. Understanding the mechanisms of gas transport in shale matrix is crucial for development strategies. In this study, methane adsorption kinetics in shale samples were measured under different pressures and temperatures. The results of methane adsorption rate were fitted by the bidisperse diffusion model. Pore structure of the shale samples were characterized by low-pressure N 2 and CO 2 adsorption. The results showed that pressure has a negative effect on methane adsorption rate and diffusion, while the effect of temperature is positive. Combining the total organic carbon (TOC) and pore structure, methane adsorption rate and effective diffusivity were compared between all the shale samples. The methane adsorption rate under high pressure (50bar) is positively related to the TOC content. The micropore volume showed a moderate positive relation with the methane adsorption rate at 30bar. A weak positive relation exists between the TOC and effective diffusivity at low pressure and the effective diffusivity at low pressure shows an increasing trend with micropore(<2 nm) volume. A hypothetic pore model is proposed: micropore in shales controls gas diffusion as pore throat which connects pores. Highlights • This study illustrates the effect of pressure and temperature on methane adsorption rate and diffusion in shales. • The contribution of micropore volume to the macropore effective diffusivity is more significant than the TOC. • The micropores in shales need to be redefined as pore throats that connects pores rather than pore itself. [ABSTRACT FROM AUTHOR]

The existing moisture in shale samples makes the evaluation for shale gas reservoirs more difficult due to its impact on the methane adsorption capacity and pore structure measurements. This paper compares the pore structure characteristics and methane adsorption capacity between dry and wet shale samples from Perth Basin, Western Australia. Pores with size between 0.4 nm and 100 nm were quantified by low-pressure N 2 and CO 2 adsorption. The comparative results demonstrate that moisture could alter the pore size distribution for big pores (>16 nm) and small pores (0.4–16 nm) in different ways. For each sample, the moisture effect on methane adsorption in shales changes with pressure: moisture effect on methane adsorption is more pronounced at lower pressure than higher pressure. For all samples, the effect of moisture on methane adsorption is related to the total organic carbon (TOC) content. Moisture could reduce methane adsorption by blocking clay- hosted small pores directly and organic matter-hosted small pores indirectly in high TOC samples. This phenomenon can effectively lead to a reduced Langmuir volume (V L ) and increased Langmuir pressure (P L ) when moisture exists. [ABSTRACT FROM AUTHOR]

Polycarbonate (PC) substrate is well suited for culturing human mesenchymal stem cells (MSCs) with high proliferation rate, low cell apoptosis rate and negligible cytotoxic effects. However, little is known about the influence of PC on MSC activity including senescence, differentiation and secretion. In this study, the PC cell culture insert was applied for human MSC culture and was compared with polystyrene (PS) and standard tissue culture plate (TCP). The results showed that MSCs were able to adhere on PC surface, exhibiting a spindle-shaped morphology. The size and distribution of focal adhesions of MSCs were similar on PC and TCP. The senescence level of MSCs on PC was comparable to that on TCP, but was significantly lower than that on PS. MSCs on PC were capable of self-renewal and differentiation into multiple cell lineages, including osteogenic and adipogenic lineages. MSCs cultured on PC secreted a higher level inflammatory cytokines and pro-angiogenic factors including FGF2 and VEGF. Conclusively, PC represents a promising cell culture material for human MSCs. [ABSTRACT FROM AUTHOR]

A chemoenzymatic synthesis of the veterinary antibiotic florfenicol is described. The key step involves the dynamic reductive kinetic resolution (DYRKR) of a keto ester by using a ketoreductase‐02 (KRED‐02) to afford the two contiguous stereocenters of the (2S,3R)‐cis‐1,2‐amino alcohol intermediate in >99 % ee and a diastereomeric ratio (dr) of 99 %. This green biocatalysis is environmental friendly with high enantioselectivity and product yields. Two methods for the nucleophilic fluorination step involved the use of aziridines and cyclic sulfates to safely prepare fluoroamines with high regioselectivity. Additional studies have indicated that KRED‐02 can also be used to afford chiral alcohol (S)‐21 in good yields with high enantioselectivity. This study shows that the integration of biocatalysis into organic synthesis can be useful and provide industrial opportunities for applications of florfenicol. [ABSTRACT FROM AUTHOR]

Selectivity of the Zirconia-based amperometric gas sensors can be easily controlled via manipulating the applied bias voltage. Nevertheless, poor sensitivity and inadequate response signal hindered their research foreground. Recently, light-regulated electrochemical reaction has been confirmed to be helpful in improving the electrocatalytic activity of photoactive sensing materials, herein, we studied the impact of UV illumination on the sensing performance of zirconia-based amperometric gas sensor, with utilizing photoactive ZnO sensing electrode and Pt counter electrode (vs. Mn-based reference electrode). Through manipulating the applied bias voltage, the sensor demonstrates acceptable selectivity to C 3 H 6 against CO and NO. Moreover, after illuminated by UV light, response signal to all the examined hazardous gases is enhanced. Interestingly, relatively large enhancement is solely observed for sensing C 3 H 6 , leading to simultaneous improvements in the sensitivity and selectivity for the sensor operated upon illumination. These promising results shed light on an alternative strategy for artificially tailoring gas sensing characteristics via light-regulated amperometric gas sensors. [ABSTRACT FROM AUTHOR]

[Display omitted] • A bottom-up strategy is used to fabricate regenerated cellulose/GO nanofluidic membrane (TACM). • TACM had well-aligned nanochannels and negatively charged surfaces. • TACM exhibited good mechanical properties and excellent ionic conductivity (0.65 S m−1). • TACM was used in health monitoring and alerting systems. Nanofluids with directional, selective, and efficient ion-transport properties are widely used in energy-conversion research. However, designing wearable nanofluidic systems for personal health monitoring is challenging owing to the large size of the test equipment, complex preparation process, and stringent biosafety requirements. Herein, we present a bottom-up strategy, integrating structural orientation, densification, and charge, to prepare a robust regenerated cellulose/graphene oxide nanofluidic membrane (TACM) comprising well-aligned nanochannels (3–4 nm) and negatively charged surfaces. The TACM exhibited high strength (76.27 MPa) and toughness (24.56 MJ m−3) as well as excellent ionic conductivity (0.65 S m−1) at low salt concentrations (<0.001 mM), attributed to the selective transport properties of the ordered charged nanochannels for oppositely charged ions, as demonstrated by experiments and finite-element simulations. In addition, we fabricated a sweat-sensing system incorporating the TACM as a core, which successfully monitored sweat changes during various aerobic and anaerobic exercises and provided health alerts. This study contributes toward the application of biomass-based nanofluids in health monitoring and alerting systems. [ABSTRACT FROM AUTHOR]

To improve the power density and energy density of vanadium flow batteries (VFBs), a novel Ti x O y -loaded carbon felt (Ti x O y -CF) electrode is designed, fabricated, and applied. Ti x O y (consisted of TiO 2 and Ti 4 O 7) has the advantages of easy preparation, high electrical conductivity, good stability, etc. It is evenly distributed on carbon felt and shows high catalytic efficiency on V2+/V3+ redox couple to facilitate the electrochemical kinetics of the vanadium redox reactions. As a result, the VFB assembled with Ti x O y -CF achieves a high energy efficiency of 82.0% at a current density of 200 mA cm−2, and maintains 77.9% energy efficiency at 260 mA cm−2. In addition, the VFB with Ti x O y -CF exhibits good stability and high capacity retention within 400 cycles at 100 mA cm−2. This work provides a new perspective for the development of highly active electrodes for VFBs. [Display omitted] • A novel Ti x O y -loaded carbon felt (Ti x O y -CF) electrode is fabricated for VFB. • The Ti x O y is consisted of TiO 2 and Ti 4 O 7. • The Ti x O y -CF with abundant oxygen vacancies speeds up reaction rate for V3+/V2+. • The VFB assembled with Ti x O y -CF shows better electrochemical performance. [ABSTRACT FROM AUTHOR]

La 0.8 Sr 0.2 MnO 3 (LSMn) was prepared as a sensing electrode (SE) for mixed-potential type NO 2 sensors, and the effects of porous micromorphology on sensing performance were studied. The results showed that the grain size of La 0.8 Sr 0.2 MnO 3 and the pore size of the SEs were regulated by sintering time. The sensitivity of the sensors increased and then decreased as the pore size increased. Selectivity was optimized via the sintering time. Finally, a NO 2 sensor with SEs sintered at 1100 °C for 2 h showed commercially viable performance at 550 °C. These results indicate that the regulation of porous LSMn SE by sintering time could be applied in mixed-potential type NO 2 sensors and is therefore a candidate for the monitoring of high-temperature exhaust. • The effects of SE micromorphology on sensing performance were investigated by extending the sintering time. • Excellent sensing performance of the sensor was achieved after the SE was sintered at 1100 °C for 2 h. • The effects of pore size on sensing performance were discussed. [ABSTRACT FROM AUTHOR]

In recent years, Vortioxetine derivatives have attracted much attention as main protease inhibitors of SARS‐CoV‐2. In this study, the structure‐activity relationship of 32 Vortioxetine derivatives was studied by CoMFA and CoMSIA models. The results show that CoMFA (q2=0.522, r2=0.996) and CoMSIA (q2=0.562, r2=0.934) have good estimation stability and prediction ability. Subsequently, through the analysis of 3D‐QSAR model, we designed four novel compounds, and verified that the pharmacokinetic properties of the new molecules were superior to compound 28 by ADMET, and verified the key amino acid action sites of the new molecule by molecular docking. Finally, the new molecules was compared with compound 28 by molecular dynamics simulation and MMPBSA, which further verified the efficacy of the new molecules, wherein the binding free energy N1 (ΔG=−161.38 kJ/mol)>N4 (ΔG=−154.19 kJ/mol)>C28 (ΔG=−129.13 kJ/mol), indicating that the newly designed drug molecules are more suitable for subsequent experimental verification. The findings presented herein can offer valuable guidance for the design and development of efficacious and innovative inhibitors targeting the SARS‐CoV‐2 main protease. [ABSTRACT FROM AUTHOR]

Post-deposition rapid thermal annealing (RTA) was performed on multilayered films consisting of a Mn capping layer on top of CoCrPt/CrTi/NiAl. High coercivities were achieved even at low M[sub r]t values and coercivity values increased more than that would have been predicted by the decrease in magnetization values. This is most likely due to the significant decrease in intergranular exchange coupling, as shown by the δM measurement. Transmission electron microscopy characterization indicates no apparent grain growth and no visible improvement in CoCrPt crystallographic texture after RTA. It is believed that the preferential diffusion of Mn into CoCrPt grain boundaries promotes magnetic grain isolation. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The catalytic activity of an oxygen-pumping electrode is very important to the performance of amperometric NO x (NO and NO 2) sensors. To enhance the stability of electrochemical NO x sensors based on Pt electrodes, we fabricated sensitive electrodes of Pt-based materials doped with small and different Au contents on 8% mol Y 2 O 3 -stabilized ZrO 2 (8YSZ) solid electrolyte substrates by screen printing and high-temperature co-firing. The effects of Au on the porous Pt electrode's catalytic activity and long-term stability were investigated, and the results are as follows. First, the catalytic capacity of the Pt–Au alloy electrode decreases with increasing Au content due to the inhibition of the oxygen adsorption on Au, which decreases the amount of oxygen participating in the reaction at triple-phase boundaries (TPBs). Second, the catalytic ability of the alloy electrode decreases exponentially with aging time due to the reduction in the length of TPBs caused by the significant reduction in the number of holes in the electrode, and the oxidation of Pt. In addition, the conductivity decay rate of the electrode decreases with increasing Au doping. This indicates that Pt-based electrodes doped with varying Au contents, long-term, and high-temperature aging have notably regular effects on the catalytic activity of oxygen-pumping electrodes, for which we have developed a model of Au passivation and the synergistic effect of aging time on the activity of Pt-based oxygen-pumping electrodes. [Display omitted] • DFT and EIS experiments were combined to elucidate the role of Au passivation. • The aging mechanism of electrodes was illustrated by long-term aging tests. • Synergistic effect of Au passivation and aging on catalytic activity was modeled. [ABSTRACT FROM AUTHOR]

To improve yield in lettuce during indoor cultivation, far-red radiation (FR, 700–800 nm) is often added to the photosynthetic active radiation (PAR, 400–700 nm). Different scenarios was applied in this study: in one scenario FR is applied throughout the 16 h photoperiod (FR-Day); in another scenario FR is applied for a short duration (1 h) at the end of the day (FR-EOD). We have shown that FR-Day is optimal for improving yield, whereas FR-EOD is optimal for production efficiency (Zou et al., 2019). Here, we evaluated the impact of both scenarios on the postharvest quality of lettuce. Shelf-life of excised packaged (polyethylene film) leaves was monitored during dark storage at 4 and 16 ℃, respectively. FR during cultivation decreased the content of major health-promoting metabolites at harvest, especially under FR-Day. At 4 ℃, shelf-life was not affected by the cultivation regime. At 16 ℃, instead, FR was associated with increased postharvest deterioration rate and reduced overall visual quality throughout storage. The reduced shelf-life following FR during cultivation was related to elevated O 2 •− content along with decreased activity of enzymatic (superoxide dismutase) and reduced levels of non-enzymatic (carotenoids, total phenolics, and flavonoids) antioxidants. We conclude that FR during cultivation especially under FR-Day is associated with reduced nutraceutical quality at harvest, and potentially shorter shelf-life. Notably, the latter was only observed under inappropriate postharvest temperature management. • Additional FR during cultivation decreases nutraceutical quality at harvest. • This is more evident when applied throughout rather than at the end of day. • FR during cultivation does not affect shelf-life under optimal storage temperature. • FR during cultivation decreases shelf-life under supra-optimal storage temperature. • FR attenuates the postharvest activation of antioxidant networks. [ABSTRACT FROM AUTHOR]