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Ground heat exchangers are key component of ground-coupled heat pump systems, and their thermal response is therefore very important for ground-coupled heat pump system design and operation. This paper proposes a new hourly simulation method, and uses it to study the performance improvement potential for the ground-coupled heat pump system. First, with an effective U-pipe shank spacing determined by the calculated and measured borehole thermal resistance, a reasonable and accurate fluid temperature prediction method is developed, and the hourly energy performance simulation method is also proposed accordingly with the Fast Fourier Transform superposition algorithm. This hourly simulation method is validated using experimental data collected from a well-designed ground-coupled heat pump experiment platform, which shows that the maximum absolute error for the predicted fluid temperature is smaller than 1.04 °C. Second, using the proposed hourly simulation method, a framework for the energy performance simulation of an office building served by the ground-coupled heat pump system is developed. Impact factors on ground-coupled heat pump system performance are systematically analyzed using this simulation method, and the results show that performance can be improved with shorter operation schedules and lower heat fluxes. [ABSTRACT FROM AUTHOR]

The interval multiple attribute decision-making problems are studied in this paper, where the preference information on attributes is expressed with preference orderings, linguistic terms, interval numbers, and inequality constraints among partial attribute weights. An approach is proposed to determine the attribute weights based on the preference information on attributes and the interval decision matrix. Firstly, preference orderings, linguistic terms, and interval numbers are normalized and aggregated into the group opinions, based on which an optimization model is set up to calculate the subjective attribute weights by including inequality constraints among partial attribute weights in the model. Then, based on the interval decision matrix, the entropy method is adopted to calculate the objective attribute weights, which is integrated with the subjective weights so that both the subjective preference information and the objective information in the decision matrix are reflected. Finally, an example is used to illustrate the proposed approach. [ABSTRACT FROM AUTHOR]

Background and aims: Nitrogen (N) deficiency and drought are two key limiting factors for rice production worldwide, but the relationship of drought stress with N homeostasis in rice is rarely advanced. The aim of this study was to dissect the physiological effects of drought stress on rice growth that coupled unbalanced N metabolism.Results: Water-deficient stress (WD) limited stomatal aperture function and activity of Rubisco carboxylase to photosynthesis. The rate of total electron transport (Jt) and the electron to carboxylation (Jc) were considerably decreased, whereas the proportion of e− flow to photorespiration was stimulated by WD, especially at 1600 μmol m−2 s−1 PPFD. Concurrently, the expressions of glycolate oxidase genes (GOX1, GOX5) and glycine decarboxylase complex (GDCH, GDCP and GDCT) were significantly induced in leaves of WD treatment, which led to the accumulation of reactive oxygen species in leaves. With the photosynthetic change, nitrate uptake and reduction were suppressed. Moreover, the enhanced photorespiration generated excess NH3 accumulation in leaves and stimulated the expressions of GS1;1, GS1;2 and GS2, which were tightly coupled with the expressions of PEPC1 and PEPC2 under WD stress.Conclusions: Our results suggest that the inhibited nitrate reduction associated with diminished electron transport rate, and the photorespiration-associated accumulation of hydrogen peroxide and NH3 were critical in the drought-induced rice growth inhibition. [ABSTRACT FROM AUTHOR]

In nearly all large-scale terrestrial ecosystem models, soil respiration is represented as a function of soil temperature. However, the relationship between soil respiration and soil temperature is highly variable across sites and there is often a pronounced hysteresis in the soil respiration-temperature relationship over the course of the growing season. This phenomenon indicates the importance of biophysical factors beyond just temperature in controlling soil respiration. To identify the potential mechanisms of the seasonal soil respiration-temperature hysteresis, we developed a set of numerical models to demonstrate how photosynthesis, soil moisture, and soil temperature, alone and in combination, affect the hysteresis relationship. Then, we used a variant of the model informed by observations of soil respiration, soil temperature, photosynthesis, and soil moisture from multiple mesic and semi-arid ecosystems to quantify the frequency of hysteresis and identify its potential controls. We show that the hysteresis can result from the seasonal cycle of photosynthesis (which supplies carbon to rhizosphere respiration), and soil moisture (which limits heterotrophic respiration when too low or too high). Using field observations of soil respiration, we found evidence of seasonal hysteresis in 9 out of 15 site-years across 8 diverse biomes. Specifically, clockwise hysteresis occurred when photosynthesis preceded seasonal soil temperature and counterclockwise hysteresis occurred when photosynthesis lagged soil temperature. We found that across all sites, much of the respiration-temperature lag was explained by the decoupling of photosynthesis and temperature, highlighting the importance of recently assimilated carbon to soil respiration. An analysis of observations from 129 FLUXNET sites revealed that time lags between gross primary productivity (a proxy for canopy photosynthesis) and soil temperature were common phenomena, which would tend to drive counterclockwise hysteresis at low-latitude sites and clockwise hysteresis at high-latitude sites. Collectively, our results show that incorporating photosynthesis and soil moisture in the standard exponential soil respiration-temperature model (i.e., Q 10 model) improves the explanatory power of models at local scales. [ABSTRACT FROM AUTHOR]

Understanding the hydrogen adsorption of porous materials is crucial to the design of high-efficiency hydrogen isotope separation materials. Much importance has been attached to tailoring the structures of materials, while the thermal management during the adsorption is often ignored. Here, we have experimentally found that the hydrogen adsorption capacity of a 5A molecular sieve (5A) is improved by enhancing its thermal conductivity. It can be facilely achieved by constructing rich and firm thermally conductive networks by filling graphite. 5A with 30 wt. % graphite shows a high thermal conductivity of 0.97 W m−1 K−1 and a fast thermal response. Notably, it also displays an enhancement of 15.6 ml/g normalized hydrogen adsorption capacity compared to the neat 5A. This indicates that there is a close relationship between thermal conductivity and hydrogen adsorption. The above demonstrations show that thermal management plays a significant role in hydrogen adsorption and should be seriously considered for designing the materials of hydrogen isotope separation. [ABSTRACT FROM AUTHOR]

Now we are entering the era of the Internet of Everything (IoE) and billions of sensors and actuators are connected to the network. As one of the most sophisticated IoE applications, real-time video analytics is promising to significantly improve public safety, business intelligence, and healthcare & life science, among others. However, cloud-centric video analytics requires that all video data must be preloaded to a centralized cluster or the cloud, which suffers from high response latency and high cost of data transmission, given the scale of zettabytes of video data generated by IoE devices. Moreover, video data is rarely shared among multiple stakeholders due to various concerns, which restricts the practical deployment of video analytics that takes advantages of many data sources to make smart decisions. Furthermore, there is no efficient programming interface for developers and users to easily program and deploy IoE applications across geographically distributed computation resources. In this paper, we present a new computing framework, Firework, which facilitates distributed data processing and sharing for IoE applications via a virtual shared data view and service composition. We designed an easy-to-use programming interface for Firework to allow developers to program on Firework. This paper describes the system design, implementation, and programming interface of Firework. The experimental results of a video analytics application demonstrate that Firework reduces up to 19.52 percent of response latency and at least 72.77 percent of network bandwidth cost, compared to a cloud-centric solution. [ABSTRACT FROM AUTHOR]

Ruthenium dissolution is an inevitable issue for an anodic electrocatalyst in direct methanol fuel cells (DMFCs). Carbon nitride (C3N4) decoration derived from the carbonization of melamine simultaneously promoted a PtRu electrocatalyst's stability and electrocatalytic activity toward concentrated methanol ascribed to the additional active sites from C3N4. [ABSTRACT FROM AUTHOR]

Endocrine disrupting chemicals (EDCs) can exhibit adverse effects by increasing or blocking hormonal activities as agonists or antagonists through nuclear receptors. Computational toxicology research provides a fast and automated screening tool for determining the potential effects of EDCs. Here, we collected a large dataset of known hormonal activities to develop ternary classification models of androgen receptor (AR) and thyroid hormone receptor (TR), in combination linear discriminant analysis (LDA), classification and regression trees (CART), and support vector machines (SVM). The optimum model for classifying AR and TR activities was SVM. These newly developed models constitute a rapidly systematic early-warning technical system for identifying different hormone activities. [ABSTRACT FROM AUTHOR]

In lamivudine-refractory chronic hepatitis B (CHB) patients, discontinuation of lamivudine therapy may lead to loss of lamivudine-resistant hepatitis B virus (HBV) and reappearance of wide-type HBV as dominant strains, yet the underlying mechanism remains unclear. In this study, we cloned wide-type and lamivudine-resistant HBV genomes from the sera of a CHB patient who stopped lamivudine therapy after occurrence of resistant virus and determined the biologic properties of the two isolates in hepatoma cell lines. Sequencing reverse transcriptase region of HBV revealed that the patient developed lamivudine-resistant mutations (rtV173 L, rtL180 M, and rtM204 V) 36 months after the start of lamivudine therapy, and lamivudine-resistant mutants reversed to wild-type after the treatment was stopped for 8 months. Our data showed that the wild-type and mutant isolates had similar transcriptional and translational activity. However, comparison of intracellular and released HBV DNA levels showed that replication efficiency of the mutant virus was approximately 50% of wild-type HBV, while the infectivity of released virus was not affected by the lamivudine-resistant mutations. In conclusion, the reversion of lamivudine-resistant mutants to wild-type HBV after discontinuation of lamivudine in hepatitis B patients may be attributed to better replication fitness of wild-type HBV. [ABSTRACT FROM AUTHOR]

The structural and mechanical properties of 9R diamond and 12R diamond have been investigated by using the first-principles calculations. The elastic constants, bulk modulus and Young’s modulus at various pressures have been investigated. The elastic anisotropy under pressure from 0 to 100 GPa has been studied. From our calculations, we found that 9R diamond and 12R diamond have similar high elastic constants and elastic modulus as lonsdaleite and diamond. The detailed ideal strength calculations show that 9R diamond and 12R diamond are intrinsic superhard materials. [ABSTRACT FROM AUTHOR]

The mTOR signaling pathways regulate cell growth and are involved in multiple human diseases. Here, we identify UBTOR, a previously unannotated gene as a functional player in regulating cell growth and mTOR signaling. Reduction of UBTOR function in cultured hippocampal neurons and PC12 cells promotes neurite outgrowth. UBTOR depletion activates mTOR signaling and promotes cell growth, whilst UBTOR overexpression suppresses colony formation in cancer cell lines. Studies in cultured cells and zebrafish model show that UBTOR inhibits mTOR signaling by stabilizing the mTOR complex component DEPTOR, and ubtor gene disruption result in higher mTOR activity and aggravate HRAS(G12V) induced neoplasia in the zebrafish. Lastly, UBTOR depletion promotes tumor growth and mTOR signaling in a xenograft mouse model. Together, our results demonstrate how UBTOR regulates cell growth and neoplasia via mTOR signaling. [ABSTRACT FROM AUTHOR]

Highlights • A new classifier, ProCRCIS, provides a probabilistic interpretation for ISCRC. • Bound with ProCRCIS, a new feature extraction method, ProCR-ODP-IS, is designed. • An iterative strategy is applied to solving the proposed optimization problem. Image set based collaborative representation and classification(ISCRC) has been proposed and achieved state-of-the-art performance. Though ISCRC works well for Image set based face recognition(ISFR), the classification mechanism of ISCRC is still unclear. Besides, another challenge that ISCRC encountered is to deal with the high-dimensional data. In this paper, we first propose a novel Probabilistic Collaborative Representation based Classifier for Image Set (ProCRCIS), which is interpreted from a probabilistic viewpoint. Then, according to the reconstruction residual-based classification rule of ProCRCIS, we propose a novel dimensionality reduction method, called Probabilistic Collaborative Representation based Orthogonal Discriminative Projection for Image Set(ProCR-ODP-IS). The goal of ProCR-ODP-IS is to find a projection space such that the between-class reconstruction residual is maximized and the within-class reconstruction residual is minimized simultaneously. Hence, this projected space can fit ProCRCIS very well. Extensive experimental results on different datasets demonstrate the superiority of the proposed method compared to the state-of-the-arts. [ABSTRACT FROM AUTHOR]

• ZSM-5 zeolite doped with Zn species showed excellent EDC cracking performance. • The acidity of the zeolite catalyst played a decisive role in EDC cracking reaction. • The catalytic performance was investigated by DFT calculations. The acidity and porosity of zeolite catalysts are crucial parameters affecting the catalytic performance. In this work, alkali treatment and metal species loading were used to modify the porosity and acidity of ZSM-5 zeolite to prepare an efficient catalyst for the 1,2-dichloroethane cracking reaction. After optimization, the highly active catalyst Zn (1%) /ZSM-5-120 was obtained, and 78% conversion of EDC and 99% selectivity toward VCM could be achieved under the conditions of 300 °C and 3.0 h−1 (WHSV). A detailed investigation was conducted on the effects of acidity, texture properties and metal species loaded on ZSM-5 zeolite on the 1,2-dichloroethane cracking reaction. Catalytic cracking of 1,2-dichloroethane to produce Vinyl Chloride Monomer using zeolite catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

Silk gland genes of Bombyx mori can have strict spatial expression patterns, which impact their functions and silk quality. However, our understanding of their regulation mechanisms is currently insufficient. To address this, the middle silk gland (MSG) and posterior silk gland (PSG) of the silkworm were investigated. Gene ontology annotation showed that spatially specific expressed genes were involved in the formation of H3k9me and chromatin topology. Chromatin conformation data generated by Hi-C showed that the topologically associated domain boundaries around FibL and S ericin1 genes were significantly different between MSG and PSG. Changes in chromatin conformation led to changes in chromatin activity, which significantly affected the expression of nearby genes in silkworm. Chromatin accessibility regions of MSG and PSG were analyzed using FAIRE-seq, and 1006 transcription factor motifs were identified in open chromatin regions. Furthermore, the spatial-specific expression patterns of silk gland genes were mainly associated with homeobox-contained transcription factors, such as POU-M2, which was specifically bound and relatively highly expressed in the MSG. The regulatory network mediated by POU-M2 regulated most of the spatial-specific expressed genes in MSG, such as ADH1. These results can aid in improving silk performance, optimizing silkworm breeding, and improving the gene spatial regulatory model research for insects. • The chromatin conformation shows spatial difference between MSG and PSG. • Spatially dynamic changes in chromatin activity influence the spatial regulation of silk protein genes in silk gland. • Chromatin accessibility in active chromatin regions mediates the spatial regulatory network of silk gland genes. • Transcriptional factor POU-M2 was identified as a key regulator of MSG specific expressed genes. • The specific expression of ADH1 gene in MSG is regulated by POU-M2. [ABSTRACT FROM AUTHOR]

• Five multimorbidity clusters were identified among middle-aged and older adults in China: minimal disease, arthritis, cardiovascular disease, lung/asthma, and multisystem morbidity. • The multisystem morbidity group had the highest use in outpatient, inpatient and self-treament healthcare, and the highest cost in self-treatment. • The five groups did not show significant differences in outpatient costs. While the lung/asthma and arthritis groups reported lower inpatient costs than other groups. This study investigated multimorbidity patterns among middle-aged and older Chinese people and whether healthcare costs varied among different multimorbidity patterns. Data were from the 2011–2018 waves of the China Health and Retirement Longitudinal Study (CHARLS). We included 20,855 unique observations with information coming from their last wave of interviews and aged at least 45 years or older. Latent class analysis (LCA) was performed to classify individuals with common multimorbidity clusters based on 14 self-reported chronic diseases. Healthcare costs were from participants' self-reports and categorized into outpatient, inpatient, and self-treatment. Two-part regression was performed to analyze the association of multimorbidity patterns with healthcare costs. Five multimorbidity clusters were identified: minimal disease, arthritis, cardiovascular disease (CVD), lung/asthma, and multisystem morbidity. The multisystem morbidity group had the highest use in all three types of healthcare and the highest self-treatment cost. Compared with the minimal disease group, the other four groups did not show significant differences in outpatient costs. Relative to the minimal disease group, the lung/asthma group reported lower inpatient costs. Healthcare use and costs varied across multimorbidity patterns among middle-aged and older Chinese people. Implementing an integrated care plan for multimorbidity is suggested to improve the cost-effectiveness of healthcare provision and reduce the financial burden of the healthcare system. Reimbursement policy design should also take multimorbidity patterns into account. [ABSTRACT FROM AUTHOR]

Background: While mother-to-child transmission (MTCT) of hepatitis B virus (HBV) remains a significant challenge in China, research investigating the effectiveness of the September 2017 pilot program to eliminate MTCT of HIV, syphilis, and HBV is limited. Baoan district, which has a higher-than-average rate of hepatitis B infection among pregnant women and strong support from the government, was one of six national pilot districts selected for the program. Therefore, this study aims to assess the progress and implementation of the elimination of MTCT of HBV in Baoan district over a period of 5 years. Methods: Data was collected from the national information system for the prevention of MTCT, registration forms, and follow-up forms of pregnant women and their live births from 2018 to 2022. Joinpoint models were used to analyze changing trends over time, calculating annual percentage change (APC) and the corresponding 95% confidence interval (95%CI). Multivariate logistic regression models were used to analyze risk factors for HBV MTCT. Results: From 2018 to 2022, the coverage of HBV screening during pregnancy increased from 98.29 to 99.55% (APC = 0.30, P = 0.012). The coverage of HBV early screening within 13 gestational weeks increased from 40.76 to 86.42% (APC = 18.88, P = 0.033). The prevalence of maternal HBV infection declined by an APC of − 3.50 (95% CI -6.28 ~ − 0.63). The coverage of antiviral therapy among high-risk pregnant women increased from 63.59 to 90.04% (APC = 11.90, P = 0.031). Coverage for timely administration of hepatitis B immunoglobulin, hepatitis B birth dose vaccine, and three-dose hepatitis B vaccination remained consistently above 97.50%. The coverage of post-vaccination serological testing (PVST) in high-risk infants was 56.15% (1352/2408), and the MTCT rate of HBV was 0.18%. Mothers with high-school education or below (OR = 3.76, 95% CI 1.04 ~ 13.60, P = 0.04) and hepatitis B e antigen (HBeAg) positivity (OR = 18.89, 95% CI 1.98 ~ 18.50, P = 0.01) had increased MTCT risk. Conclusions: The implementation of comprehensive prevention strategies in Baoan district, including screening, treatment, and immunoprophylaxis, has proven effective in maintaining the MTCT of HBV at an extremely low level. However, it remains crucial to raise public awareness, specifically on the importance of improving the coverage of PVST for infants exposed to HBV. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) supported metal nanoparticles (MNPs) (MNPs@MOFs) composites, as a class of effective functional materials, have been extensively explored because of the synergetic effect of MOFs and MNPs. Lots of synthesized methods are developed to synthesize MNPs@MOFs composites. These strategies can be generally divided into four main synthesis strategies: ship‐in‐the‐bottle, bottle‐around‐the‐ship, one‐pot, and sandwich assembly approaches. In this review, the recent synthesized strategies are discussed and summarized for the design and fabrication of different MNPs@MOFs composites. Then, the catalytic applications of some MNPs@MOFs composites are presented. Lastly, the challenges and future perspectives are also pointed out in this hot research filed. [ABSTRACT FROM AUTHOR]

Joint capsule fibrosis, a common complication of joint immobilization, is mainly characterized by abnormal collagen deposition. The present study aimed to investigate the effect of extracorporeal shock wave therapy (ESWT) on reduced collagen deposition in the joint capsule during immobilization-induced joint capsule fibrosis. Additionally, the potential involvement of the adenosine A2A receptor (A2AR)-Neurotrophic factor e2-related factor 2 (Nrf2)/Haem oxygenase-1 (HO-1) pathway was explored. Thirty 3-month-old male Sprague–Dawley rats were randomly assigned to five groups: control (C), immobilization model (IM), natural recovery (NR), ESWT intervention (EI), and ESWT combined with A2AR antagonist SCH 58261 intervention (CI). After the left knee joints of rats in the IM, NR, EI and CI groups were immobilized using a full-extension fixation brace for 4 weeks, the EI and CI groups received ESWT twice a week for 4 weeks. The CI group was also treated with ESWT following intraperitoneal injection of SCH 58261 (0.01 mg/kg) for 4 weeks. The range of motion of the left knee joint was measured, and the protein levels of collagens I and III, A2AR, phosphorylated-protein kinase A/protein kinase A (p-PKA/PKA), p-Nrf2/Nrf2, and HO-1 were analysed by Western blotting. The IM and NR groups showed significantly greater arthrogenic contracture than the C group (P < 0.05). Compared to the NR group, the EI and CI groups exhibited significant improvement in arthrogenic contracture (P < 0.05). Conversely, the EI group showed lower contracture than the CI group (P < 0.05). Similar results were observed for collagen deposition and the protein levels of collagens I and III. The intervention groups (EI and CI groups) showed higher levels of p-Nrf2/Nrf2 and HO-1 than the NR group (P < 0.05). Moreover, the EI group exhibited higher levels of p-PKA/PKA, p-Nrf2/Nrf2, and HO-1 than the CI group (P < 0.05). However, no significant difference was found in the A2AR levels among the five groups (P > 0.05). ESWT may activate A2AR, leading to the phosphorylation of PKA. Subsequently, Nrf2 may be activated, resulting in the upregulation of HO-1, which then reduces collagen deposition and alleviates immobilization-induced joint capsule fibrosis. [ABSTRACT FROM AUTHOR]

The reconstruction of 3D shapes from a single view has been a longstanding challenge. Previous methods have primarily focused on learning either geometric features that depict overall shape contours but are insufficient for occluded regions, local features that capture details but cannot represent the complete structure, or structural features that encode part relationships but require predefined semantics. However, the fusion of geometric, local, and structural features has been lacking, leading to inaccurate reconstruction of shapes with occlusions or novel compositions. To address this issue, we propose a two-stage approach for achieving 3D shape reconstruction. In the first stage, we encode the hierarchical structure features of the 3D shape using an encoder-decoder network. In the second stage, we enhance the hierarchical structure features by fusing them with global and point features and feed the enhanced features into a signed distance function (SDF) prediction network to obtain rough SDF values. Using the camera pose, we project arbitrary 3D points in space onto different depth feature maps of the CNN and obtain their corresponding positions. Then, we concatenate the features of these corresponding positions together to form local features. These local features are also fed into the SDF prediction network to obtain fine-grained SDF values. By fusing the two sets of SDF values, we improve the accuracy of the model and enable it to reconstruct other object types with higher quality. Comparative experiments demonstrate that the proposed method outperforms state-of-the-art approaches in terms of accuracy. [ABSTRACT FROM AUTHOR]

The aim of the work described here was to investigate the efficacy and potential mechanisms of low-intensity pulsed ultrasound (LIPUS) for the treatment of arthrogenic contracture induced by immobilization in rabbits. The left knee joint of rabbits was immobilized for 6 wk to establish the model of extending knee joint contracture. The rabbits were divided into a control group (C), a group immobilized for 6 wk (IM-6w), a group remobilized for 1 wk (RM-1w), a group subjected to LIPUS intervention for 1 wk (LIPUS-1w), a group remobilized for 2 wk (RM-2w) and a group subjected to LIPUS intervention for 2 wk (LIPUS-2w). The degrees of arthrogenic contracture and joint capsule fibrosis were assessed, as were the levels of reactive oxygen species (ROS) and the activation status of the TGF-β1/Smad signaling pathway in the joint capsule. After immobilization for 6 wk, the degrees of arthrogenic contracture and joint capsule fibrosis increased. The ROS level increased, as evidenced by an increase in malondialdehyde content and a decrease in superoxide dismutase content. In addition, the TGF-β1/Smad signaling pathway was significantly activated. The degrees of knee joint contracture increased in the first week after remobilization and decreased in the second week. Furthermore, joint capsule fibrosis continued to develop during the 2 wk of remobilization, and the ROS level increased, while the TGF-β1/Smad signaling pathway was significantly activated. LIPUS effectively reduced the level of ROS in the joint capsule, which further inhibited activation of the TGF-β1/Smad signaling pathway, thereby improving joint capsule fibrosis and reducing arthrogenic contracture. The high ROS levels and overactivation of the TGF-β1/Smad signaling pathway may be reasons why immobilization induces knee joint capsule fibrosis. LIPUS can alleviate the degree of knee joint capsule fibrosis induced by immobilization by inhibiting the production of ROS and the activation of the TGF-β1/Smad signaling pathway. [ABSTRACT FROM AUTHOR]

As well known, ruthenium is electrochemically unstable in direct methanol fuel cell (DMFC) operation shortening lifetime and deteriorating performance of DMFC device. In this work, a facile methodology for improvement in stability of PtRu electrocatalyst is described, in which PtRu alloyed nanoparticles are decorated by nitrogen-doped carbon (N x C) originating from the carburization of in-situ polymerized polyaniline (PANI). Deceleration in Ru dissolution of N x C protected PtRu electrocatalyst comes from the ionized Ru atoms induced by the carburization of PANI transferring electrons from Ru to nitrogen atoms evidenced by XPS measurement, which results in higher CO tolerance during potential sweeping from 0.6 to 1.0 V versus RHE for N x C decorated PtRu electrocatalyst. Meanwhile, N x C protected PtRu electrocatalyst only losses 10% of active sites after stability estimation; in contrast, 50% of active sites are lost for bare PtRu electrocatalyst. Moreover, fuel cell test illustrates that N x C protected PtRu electrocatalyst shows comparable performance to bare PtRu electrocatalyst. [ABSTRACT FROM AUTHOR]

The Atmospheric Infrared Sounder (AIRS) provides limited hyperspectral thermal infrared (TIR) emissivity data for the retrieval of critical land surface and climate parameters in environmental research. However, the AIRS land surface emissivity (LSE) data lack accuracy, resulting in low-quality data retrieval, particularly for the lower boundary layer. In this study, a practical and effective method is proposed to derive high-accuracy AIRS LSE data and continuous emissivity spectra in the TIR range of 8–14.5 μm. The AIRS LSE is first rescaled to the Moderate Resolution Imaging Spectroradiometer (MODIS) LSE using cumulative distribution function (CDF) matching, and then the emissivity spectra are recovered from the rescaled AIRS LSE using principal component analysis (PCA) regression. The results show that rescaling the AIRS LSE significantly reduced the bias and root mean square (RMS) error in the study area of Africa and the Arabian Peninsula, and PCA regression successfully recovered the emissivity spectra in the 8–14.5 μm range from the rescaled AIRS LSE. At two validation sites in the Namib and Kalahari deserts of southern Africa, the biases of the rescaled AIRS LSE at three hinge points are 0.62% and 0.61%, respectively, and the biases of the recovered AIRS LSE spectra in the 8–12 μm TIR range are 0.53% and 0.56%, respectively. Variations in land cover homogeneity and the accuracy of the MODIS LSE are the critical factors impacting the final accuracy of the rescaled AIRS LSE and the recovered emissivity spectra. [ABSTRACT FROM AUTHOR]

Based on the first-principles calculations, the strain effects on the optical properties of direct band gap silicon crystal D135-Si were systemically investigated. The stress-strain relations and phonon spectra show that the realistic peak tensile strengths in three principle symmetry crystallographic directions [100], [010] and [001] are 4.5, 9.7 and 12.1 GPa, respectively. By imposing the pressure and strain on structure, we studied the direct-indirect band gap transitions and obtained the ranges of the direct band gap, namely 0–4 GPa on pressure, −0.07–0, −0.04–0.08, and −0.01–0.03 on strain along a- , b- and c- direction, respectively. The imaginary part of the dielectric function was calculated to analyze the optical absorption property, which shows the strong adsorption coefficients in the visible range of the sunlight. The effect of pressure on the optical absorption property of structure is the smallest, and the strain effects are gradually enhanced along c- , b- and a- direction, respectively. [ABSTRACT FROM AUTHOR]

We report herein a means of transforming TiO 2 nanotube arrays (TNAs) from an amorphous state to an anatase crystal state (denoted as ∗ TNAs), and present a single-step synthetic route for preparing CdS quantum dots (CdS QDs) as well as reduced graphene oxide (rGO) through gamma-ray irradiation. The as-prepared ∗ TNAs, CdS QDs, and rGO, which had all been subjected to gamma-ray irradiation, were then assembled together to produce the desired heterojunction (denoted as CdS QDs/rGO- ∗ TNAs). X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), ultraviolet/visible diffuse-reflectance spectroscopy (UV/Vis DRS), Fourier-transform infrared spectroscopy (FTIR), micro-Raman spectrometry (RS), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS) have been applied to characterize the appearance and performance of this photocatalyst. The photocatalytic activity of CdS QDs/rGO- ∗ TNAs towards ethylene degradation has been measured by placing it in a simulated cold-storage environment, the temperature and humidity of which were set at about 3 ± 1 °C and 75–90%, respectively. The results showed that the rate constant ( K ) of ethylene degradation could reach up to 1.07 × 10 −3  min −1 with CdS QDs/rGO- ∗ TNAs, as compared to 2.30 × 10 −4  min −1 with ∗ TNAs and 6.25 × 10 −4  min −1 with CdS QDs- ∗ TNAs, indicating that the constructed CdS QDs/rGO- ∗ TNAs constitutes a promising photocatalyst for ethylene removal in a cold storage environment. [ABSTRACT FROM AUTHOR]

Most current strategies for designing tunable locally resonant metamaterials are based on tuning the stiffness of the resonator; however, this approach presents a major shortcoming as the effective mass density is constant at a high frequency. Here, this paper reports a type of tunable locally elastic metamaterial—called “tunable fluid-solid composite.” The proposed metamaterial consists of several liquid or gas inclusions in a solid matrix, controlled through a pair of embedded pumps. Both the band gap and effective mass density at the high frequency can be tuned by controlling the liquid distribution in the unit cell, as demonstrated through a combination of theoretical analysis, numerical simulation, and experimental testing. Finally, we show that the tunable fluid-solid metamaterial can be utilized to manipulate wave propagation over a broad frequency range, providing avenues for vibration isolation and wave guiding. [ABSTRACT FROM AUTHOR]

This paper explored the application of model predictive control (MPC) technology to the TBSs hybrid free cooling system with latent heat thermal energy storage (LHTES) unit for minimizing the building operational cost without sacrificing temperature requirements. First, the system was briefly introduced and the dynamic thermal process models of building structure and LHTES unit were developed. Then, a hierarchical control structure with dynamic multi-swarm particle swarm optimization was presented to address the dimensional challenge and discontinuities in control variables. Due to the considerable decrease of optimization variable space, the method presented in this paper enables long-term simulation and application in a real controller. Simulations were carried out based on a typical TBS building located in Beijing, China. The total energy consumption of the cooling system and the control quality of indoor air temperature were used as the criteria to evaluate the performance. Compared to a defined baseline case, the optimal control method can achieve significant energy saving, i.e. up to 18%. The impacts of the size of LHTES unit and the type of building structure were discussed, as well. The active and passive heat capacity both played a catalytic role in performance of MPC. Additionally, an uncertainty analysis demonstrated that the proposed approach has strong robustness and can handle quite high errors in forecasting building disturbances from energy consumption level. In summary, the knowledge and use of the plant system and future disturbances make MPC a powerful control tool for TBS buildings for maximizing the use of renewable energy sources. [ABSTRACT FROM AUTHOR]

Key points: Na+ current inactivation is biphasic in insulin‐secreting cells, proceeding with two voltage dependences that are half‐maximal at ∼−100 mV and −60 mV. Inactivation of voltage‐gated Na+ (NaV) channels occurs at ∼30 mV more negative voltages in insulin‐secreting Ins1 and primary β‐cells than in HEK, CHO or glucagon‐secreting αTC1‐6 cells. The difference in inactivation between Ins1 and non‐β‐cells persists in the inside‐out patch configuration, discounting an involvement of a diffusible factor. In Ins1 cells and primary β‐cells, but not in HEK cells, inactivation of a single NaV subtype is biphasic and follows two voltage dependences separated by 30–40 mV. We propose that NaV channels adopt different inactivation behaviours depending on the local membrane environment. Abstract: Pancreatic β‐cells are equipped with voltage‐gated Na+ channels that undergo biphasic voltage‐dependent steady‐state inactivation. A small Na+ current component (10–15%) inactivates over physiological membrane potentials and contributes to action potential firing. However, the major Na+ channel component is completely inactivated at −90 to −80 mV and is therefore inactive in the β‐cell. It has been proposed that the biphasic inactivation reflects the contribution of different NaV α‐subunits. We tested this possibility by expression of TTX‐resistant variants of the NaV subunits found in β‐cells (NaV1.3, NaV1.6 and NaV1.7) in insulin‐secreting Ins1 cells and in non‐β‐cells (including HEK and CHO cells). We found that all NaV subunits inactivated at 20–30 mV more negative membrane potentials in Ins1 cells than in HEK or CHO cells. The more negative inactivation in Ins1 cells does not involve a diffusible intracellular factor because the difference between Ins1 and CHO persisted after excision of the membrane. NaV1.7 inactivated at 15‐­20 mV more negative membrane potentials than NaV1.3 and NaV1.6 in Ins1 cells but this small difference is insufficient to solely explain the biphasic inactivation in Ins1 cells. In Ins1 cells, but never in the other cell types, widely different components of NaV inactivation (separated by 30 mV) were also observed following expression of a single type of NaV α‐subunit. The more positive component exhibited a voltage dependence of inactivation similar to that found in HEK and CHO cells. We propose that biphasic NaV inactivation in insulin‐secreting cells reflects insertion of channels in membrane domains that differ with regard to lipid and/or membrane protein composition. [ABSTRACT FROM AUTHOR]

The response of near ground air temperature to changing precipitation regimes has received extensive attentions in climate change studies. In semi-arid and arid regions, the mean annual temperature correlates negatively with precipitation. However, it remains unclear to what extent one unit change of precipitation can trigger temperature change (i.e., the temperature sensitivity to precipitation). Taking a semi-arid region in Northwest China as a study area, we quantitatively investigated the temperature sensitivity to precipitation change. Further analysis shows that the temperature sensitivity correlates well with the Normalized Difference Vegetation Index (NDVI), indicating that vegetation plays an important role in controlling the long-term temperature sensitivity to precipitation change. Specifically, different land covers show significant differences in temperature sensitivity, with bare soil generally having a higher sensitivity while more densely vegetated areas such as forest and grassland having lower sensitivity values. This implies that vegetation contributes to reducing the temperature sensitivity to precipitation change through the land surface-atmosphere interaction in semi-arid and arid regions. [ABSTRACT FROM AUTHOR]

Microbial production of chondroitin and chondroitin-like polysaccharides from renewable feedstock is a promising and sustainable alternative to extraction from animal tissues. In this study, we attempted to improve production of fructosylated chondroitin in Escherichia coli K4 by balancing intracellular levels of the precursors UDP-GalNAc and UDP-GlcA. To this end, we deleted pfkA to favor the production of Fru-6-P. Then, we identified rate-limiting enzymes in the synthesis of UDP-precursors. Third, UDP-GalNAc synthesis, UDP-GlcA synthesis, and chondroitin polymerization were combinatorially optimized by altering the expression of relevant enzymes. The ratio of intracellular UDP-GalNAc to UDP-GlcA increased from 0.17 in the wild-type strain to 1.05 in a 30-L fed-batch culture of the engineered strain. Titer and productivity of fructosylated chondroitin also increased to 8.43 g/L and 227.84 mg/L/h; the latter represented the highest productivity level achieved to date. [ABSTRACT FROM AUTHOR]

Abstract: The uptake of nitrate by plant roots causes a pH increment in rhizosphere and leads to iron (Fe) deficiency in rice. However, little is known about the mechanism how the nitrate uptake‐induced high rhizosphere pH causes Fe deficiency. Here, we found that rice showed severe leaf chlorosis and large amounts of Fe plaque were aggregated on the root surface and intercellular space outside the exodermis in a form of ferrihydrite under alkaline conditions. In this case, there was significantly decreased Fe concentration in shoots, and the Fe deficiency responsive genes were strongly induced in the roots. The high rhizosphere pH induced excess hydrogen peroxide (H2O2) production in the epidermis due to the increasing expression of NADPH‐oxidase respiratory burst oxidase homolog 1, which enhanced root oxidation ability and improved the Fe plaque formation in rhizosphere. Further, the concentrated H2O2 regulated the phenylpropanoid metabolism with increased lignin biosynthesis and decreased phenolics secretion, which blocked apoplast Fe mobilization efficiency. These factors coordinately repressed the Fe utilization in rhizosphere and led to Fe deficiency in rice under high pH. In conclusion, our results demonstrate that nitrate uptake‐induced rhizosphere alkalization led to Fe deficiency in rice, through H2O2‐dependent manners of root oxidation ability and phenylpropanoid metabolism. [ABSTRACT FROM AUTHOR]

To purify cellulosic ethanol wastewater (CEW) and obtain algae simultaneously, culturing microalgae using CEW as the medium is a potentially promising technology. In this study, mutation breeding of Scenedesmus sp. induced by ultraviolet (UV) and ethyl methanesulfonate (EMS) was performed, and three mutant strains were screened using undiluted CEW. Among them, the mutant MU1 showed a high biomass yield of 1075 mg L−1 and biomass productivity of 39.81 mg L−1 day−1, and the lipid and protein content of MU1 can reach up to 21.4 and 41.9% (dry weight of biomass), respectively. Meanwhile, the chemical oxygen demand (COD), total ammonia nitrogen (TAN), total phosphorus (TP) and chroma (CHR) removal percentages in CEW reached to 33.5, 71.2, 46.4 and 17.8%, respectively. These results indicated that MU1 is suitable for purifying CEW and producing biomass simultaneously, providing a prospective way for CEW treatment and low-cost microalgae cultivation.ᅟ [ABSTRACT FROM AUTHOR]

Iron-bearing amendments, such as iron grit, are proved to be effective amendments for the remediation of arsenic- (As-) contaminated soils. In present study, the effect of redox condition on As fractions in As-contaminated soils remediated by iron grit was investigated, and the bioaccessibility of As in soils under anoxic condition was evaluated. Results showed that the labile fractions of As in soils decreased significantly after the addition of iron grit, while the unlabile fractions of As increased rapidly, and the bioaccessibility of As was negligible after 180 d incubation. More labile fractions of As in iron-amended soils were transformed into less mobilizable or unlabile fractions with the contact time. Correspondingly, the bioaccessibility of As in iron-amended soils under the aerobic condition was lower than that under the anoxic condition after 180 d incubation. The redistribution of loosely adsorbed fraction of As in soils occurred under the anoxic condition, which is likely ascribed to the reduction of As(V) to As(III) and the reductive dissolution of Fe-(hydr)oxides. The stabilization processes of As in iron-amended soils under the anoxic and aerobic conditions were characterized by two stages. The increase of crystallization of Fe oxides, decomposition of organic matter, molecular diffusion, and the occlusion within Fe-(hydr)oxides cocontrolled the transformation of As fractions and the stabilization process of As in iron-amended soils under different redox conditions. In terms of As bioaccessibility, the stabilization process of As in iron-amended soils was shortened under the aerobic condition in comparison with the anoxic condition. [ABSTRACT FROM AUTHOR]

Aims Contrary findings exist on the consistency between hair cortisol and salivary cortisol in assessing the basal activity of the hypothalamic-pituitary-adrenal (HPA) axis. The mismatches in temporal characteristic and the indices of hair and salivary cortisol might be potential reasons for the inconsistency. The aim of this study was to investigate the consistency between hair and salivary levels in cortisol and cortisone by directly examining the correlation between hair level and salivary level with different temporal characteristics (acute, short-term and long-term levels) and reflecting different HPA functions (basal level and reactivity level) in the well-matched time span. Main methods A longitudinal design within a five-week period was conducted in a sample of 44 healthy female college students (mean age: 18.8 yrs.; age range: 18–22 yrs) of Han nationality with the exclusion criteria, such as use of oral contraceptives or glucocorticoids and bleached hairs, etc. Four saliva samples (awakening, awakening + 30 min, awakening + 4 h and awakening + 9 h) were collected from an identical participant on three separate days with an interval of one week and 1-cm hair segment nearest to the scalp was collected two weeks later after completing saliva collection. Cortisol and cortisone in saliva and hair were simultaneously measured with high performance liquid chromatography tandem mass spectrometry. Key findings There were significantly moderate correlations in cortisol and cortisone between hair level and three-day average of single-day salivary level, but low to moderate correlations between hair level and single-point and single-day salivary level. Hair cortisol and cortisone were unrelated to single-day level and three-day average of diurnal slope and cortisol awakening response of salivary cortisol and cortisone, respectively. Significance The considerable consistency between hair level and long-term salivary level in cortisol and cortisone implies that cortisol and cortisone in hair are valid biomarkers of cumulative exposure of cortisol and cortisone to retrospectively reflect long-term basal activity of the HPA system. [ABSTRACT FROM AUTHOR]

Field electron emission from carbon nanotubes shows promising application potential in devices. Low adhesive bonding strength between the carbon nanotubes and the substrate presents a practical challenge in environments such as high field emission current density. In this paper, we report on the performance of a carbon nanotube microbundle attached to a tungsten needle by a uniform glue layer. The device is easily fabricated without complex fixture and possesses a complete array structure. After curing the glue in air, the adhesive strength between the carbon nanotubes and the needle is over 2000 N/cm2. Field emission measurements demonstrate that the maximum current density of the emitters is over 20 A/cm2 under a low applied field (<0.4 V/μm). The emitter with high current density, low emission field, and good stability has a wide range of applications in flat displays, X-ray tubes, and lamps. [ABSTRACT FROM AUTHOR]

Radiation shielding materials have attracted much attention across academia and industry because of the increasing of nuclear activities. To achieve the materials with low toxicity but good protective capability is one of the most significant goals for personal protective articles. Here, bismuth tungstate nanostructures are controllably fabricated by a versatile hydrothermal treatment under various temperatures. The crystals structure and morphology of products are detailedly characterized with X-ray diffraction, electron microscope and specific surface area. It is noteworthy that desired Bi 2 WO 6 nanosheets treated with 190 °C show the higher specific surface area (19.5 m 2 g −1 ) than that of the other two products. Importantly, it has a close attenuating property to lead based counterpart for low energy gamma-rays. Due to the less toxicity, Bi 2 WO 6 nanosheets are more suitable than lead based materials to fabricate personal protective articles for shielding low energy radiations and have great application prospect as well as market potential. [ABSTRACT FROM AUTHOR]

The NLRP3-interleukin1β (IL1β) signaling pathway is involved in monosodium urate (MSU)-mediated inflammation. The aim of this present study was to determine whether single nucleotide polymorphisms (SNPs) in the NLRP3 gene are associated with susceptibility to gouty arthritis (GA) and whether these SNPs alter the expression of components of the NLRP3-IL1β signaling pathway. The rs10754558, rs4612666, and rs1539019 SNPs were detected in 583 patients with GA and 459 healthy subjects. NLRP3 and IL1β mRNA levels in peripheral blood mononuclear cells (PBMCs) and serum IL1β levels were measured in different genotype carriers, and correlations between the NLRP3 SNPs and NLRP3 mRNA, IL1β mRNA, and serum IL1β levels were investigated. The GG genotype of NLRP3 rs10754558 was found to be significantly associated with patients with GA compared to the healthy control subjects via multivariate logistic regression analysis (adjusted OR = 2.68, P = 0.006). The CGA haplotypes were independently associated with patients with GA compared to the healthy control subjects (adjusted OR = 1.968, P = 0.02). The levels of NLRP3 mRNA, IL1β mRNA, and serum IL1β in the patients with GA were significantly different among the three genotypes of rs10754558 (all P < 0.01). The GG genotype of rs10754558 and the CGA haplotype of rs4612666-C, rs10754558-G, and rs1539019-A are both independent risk factors for primary GA development. The rs10754558 polymorphism might participate in regulating immune and inflammation responses in patients with GA by influencing the expression of components of the NLRP3 inflammasome. Future multicenter studies aimed at replicating these findings in an independent population as well as functional tests will aid in further defining the role of these SNPs in the development of GA. [ABSTRACT FROM AUTHOR]

Lead borate nanowhiskers have been successfully prepared by a facile solvothermal method. The morphologies and crystal sizes of the lead borate nanowhiskers are controlled by adjusting the amount of added ammonia hydroxide in the solvothermal reaction. The morphology evolution and structure changes are tracked during the growth process by field SEM, TEM, and XRD, respectively. The as-prepared lead borate nanowhiskers are 60–90 μm in length and 150–500 nm in diameter and possess typical single-crystal attributes. The influence of lead borate nanowhiskers on the mechanical properties, thermal conductivity, and radiation shielding performance of polymer composites is also discussed. The results show that lead borate nanowhiskers can significantly improve these properties of the composites. The excellent integrated properties contribute to the application of the materials for shielding mixed neutron and gamma radiation. [ABSTRACT FROM AUTHOR]

This paper addresses the dynamic model and active vibration control of a rigid-flexible parallel manipulator with three smart links actuated by three linear ultrasonic motors. To suppress the vibration of three flexible intermediate links under high speed and acceleration, multiple Lead Zirconium Titanate (PZT) sensors and actuators are collocated mounted on each link, forming a smart structure which can achieve self-sensing and self-actuating. The dynamic characteristics and equations of the flexible link incorporated with the PZT sensors and actuator are analyzed and formulated. The smooth adaptive sliding mode based active vibration control is proposed to suppress the vibration of the smart links, and the first and second modes of the three links are targeted to be suppressed in modal space to avoid the spillover phenomenon. Simulations and experiments are implemented to validate the effectiveness of the smart structures and the proposed control laws. Experimental results show that the vibration of the first mode around 92 Hz and the second mode around 240 Hz of the three smart links are reduced respectively by 64.98%, 59.47%, 62.28%, and 45.80%, 36.79%, 33.33%, which further verify the multi-mode vibration control ability of the smooth adaptive sliding mode control law. [ABSTRACT FROM AUTHOR]

Lead borate compounds with a formula of Pb 3 B 10 O 16 [OH] 4 synthesized via low-temperature solvothermal route are highly effective to co-shielding neutron and gamma radiations. Complementary structural characterizations and radiation shielding tests are used to determine structure/activity relations of the as-prepared materials. The morphologies and the crystal structures of the lead borate are controlled by simply adjusting the amount of added pyridine and/or ammonium hydroxide in the solvothermal reaction. In addition, a plausible mechanism is proposed to follow the formation of the lead borate with various morphologies. [ABSTRACT FROM AUTHOR]

Several new stable phases of MoS at ambient and high pressures were uncovered by using the global minimization of energy surfaces merging ab initio total energy calculations, and a phase transition order of Imm 2 → Pnma → Pm -3 m was revealed. The transition pressures are 5.5 GPa and 45.3 GPa, respectively, retrieved from the calculated formation enthalpy. The mechanical and dynamical stabilities of these phases were determined by the elastic constants and phonon dispersions. Moreover, the calculated band structures show that the Imm 2 and Pnma phases are indirect band gap semiconductors, whereas the Pm -3 m phase shows metallic character. The electron localization function calculations of these three stable phases were also been analyzed. [ABSTRACT FROM AUTHOR]

MgO thin films of different thicknesses were prepared on polished Ag-3wt%Mg alloy by an activation process at 500–650 °C under oxygen pressures of 0.5–10.0 Pa. The influence of the thickness of MgO film on the secondary electron yield of the Ag-3wt%Mg alloy is investigated. The alloy with an MgO film of moderate thickness of 65 ± 1 nm shows the highest secondary electron yield of 10. Oxygen pressure below 10.0 Pa is crucial for the formation of intact MgO film on the top surface. Computational simulation analysis reveals that the maximum yield occurs when the penetration depth of primary electrons is 13–18 nm less than the thickness of MgO film. Electron supply of this extra MgO film is allowed by an electron tunneling mechanism under certain bias voltage. The replenishment of new electrons to the electron deficient surface is crucial for obtaining optimized secondary electron yields for Ag-Mg alloy cathodes. [ABSTRACT FROM AUTHOR]

Melatonin-loaded liposomes (MLL) were successfully prepared using rapid expansion of supercritical solution technology. The effects of supercritical pressure on encapsulation efficiency (EE) and average particle size were then analysed. Meanwhile, temperature, formation time and ethanol concentration in the products were studied and optimised based on the response surface methodology (RSM). Anin vitrosimulated digestion model was also established to evaluate the release performance of MLL. The results showed that 140 bar was the best pressure for maximising the EE value using RSM optimisation, reaching up to 82.2%. MLL characterisations were performed using analytic techniques including infrared spectroscopy, transmission electron microscopy, a laser scattering particle size analyser and gas chromatograph-mass spectrometer. The size distribution was uniform, with an average diameter of 66 nm. Stability tests proved that MLL maintained good preservation duration, and residual solvent experiments indicated that only 1.03% (mass ratio) of ethanol remained in the products. Simulated release experiments indicated the slow release feature in early digestive stages and more thorough characteristics in later stages of simulated digestion. [ABSTRACT FROM PUBLISHER]

We have systematically explored the electronic structures and magnetic properties of metal Pd, Pt, Cu, Ag, Au and Zn adsorbed MoSe 2 monolayer by means of first-principles calculations. It reveals that stable chemical adsorption has been formed between the adatoms Pd, Pt, Cu, Ag, Au and MoSe 2 monolayer, however, weak physical interaction is found between Zn and MoSe 2 monolayer owing to the small adsorption energy. Both the framework structure and electronic property of the metal adsorbed MoSe 2 monolayer are slightly tuned by the adatoms. More importantly, magnetic character is introduced in Cu, Ag and Au systems. [ABSTRACT FROM AUTHOR]

The present study evaluates the seasonal photosynthetic performances of Sargassum thunbergii via chlorophyll fluorescence technique. During summer and early winter, no significant change was observed in maximum photochemical efficiency ( F v/ F m), and performance index (PIabs). During late winter and early spring, F v/ F m, and PIabs decreased significantly, implying that S. thunbergii photosystem II (PSII) suffered apparent photoinhibition. Subsequently, PSII gradually recovered during late spring and summer, as evidenced by an increase of both parameters. Throughout the year, the maximum decrease in the slope of MR/MR0 maintained low values indicated that photosystem I (PSI) was incative, the initial rate of P700 + re-reduction maintained low value indicated that cyclic electron transport (CET) were inactive; nevertheless, a seasonal down-regulation of both PSI and CET during late winter and early spring could be detected. The weak performance of PSI and CET can potentially limit the flexibility in response to winter stress and result in a delayed recovery of PSII. In conclusion, the seasonal variability of S. thunbergii photosynthetic activity was characterized by three periods: active state, down-regulation and restoration. The rapid growth during early spring was accompanied by weak photosynthetic performance, indicating that the carbohydrates consumed during this period were derived from previously stored starch. [ABSTRACT FROM AUTHOR]

Synthetic pyrethroids (SPs) are one of the most widely used pesticides and frequently detected in the aquatic environment. Previous studies have shown that SPs posed high aquatic toxicity, but information on the developmental toxicity and endocrine disruption on zebrafish ( Danio rerio ) at environmentally relevant concentrations is limited. In this study, zebrafish embryos were employed to examine the adverse effects of λ-cyhalothrin (LCT), fenvalerate (FEN), and permethrin (PM) at 2.5, 10, 25, 125, 500 nM for 96 h. The results showed these 3 SPs caused dose-dependent mortality, malformation rate, and hatching rate. Thyroid hormone triiodothyronine (T 3 ) levels were significantly decreased after exposure to LCT and FEN. Quantitative real-time PCR analysis was then performed on a series of nuclear receptors ( NRs ) genes involved in the hypothalamic–pituitary–gonadal (HPG), hypothalamic–pituitary–thyroid (HPT), hypothalamic–pituitary–adrenocortical (HPA) axes, and oxidative-stress-related system. Our results showed that LCT, FEN, and PM downregulated AR expression while upregulated ER1 expression, and caused alteration to ER2a and ER2b expression. As for the expression of TRα and TRβ , they were both decreased following exposure to the 3 SPs. LCT and PM downregulated the MR expression and FEN induced MR expression. In addition, the expression of GR was increased after treating with LCT, while it was suppressed after exposure to FEN and PM. The 3 SPs also caused various alterations to the expression of genes including AhRs , PPARα , and PXR . These findings suggest that these 3 SPs may cause developmental toxicity to zebrafish larvae by disrupting endocrine signaling at environmentally relevant concentrations. [ABSTRACT FROM AUTHOR]

The targeted delivery of a photosensitizer (PS) with appropriate carriers represents an attractive means of selectively delivering cargo to target tissues or subcellular compartments for photodynamic therapy (PDT). Herein, a three-arm distyryl BODIPY derivative conjugated with mannose units (denoted by BTM) that can co-assemble with Tween 80 to form nanomicelles (BTM-NMs) for targeted PDT is reported. MDA-MB-231 breast cancer cells recognized and specifically internalized BTM-NMs via mannose-receptor-mediated endocytosis with preferential accumulation in the lysosomes. These NMs could disassemble in cell lysosomes and subsequently induce highly efficient singlet oxygen (1O2) generation upon light irradiation. 1O2 disrupted the lysosomal membrane and promoted the escape of BTM from the lysosome into the cytoplasm, thereby resulting in the efficient and selective killing of cancer cells through PDT. This study may provide a new strategy for designing targeted PDT systems to fight cancer. [ABSTRACT FROM AUTHOR]

Boron (B) is an essential micronutrient for plants, but the molecular mechanisms underlying the uptake and distribution of B in allotetraploid rapeseed ( Brassica napus) are unclear. Here, we identified a B transporter of rapeseed, BnaC4.BOR1;1c, which is expressed in shoot nodes and involved in distributing B to the reproductive organs. Transgenic Arabidopsis plants containing a BnaC4.BOR1;1c promoter-driven GUS reporter gene showed strong GUS activity in roots, nodal regions of the shoots and immature floral buds. Overexpressing BnaC4.BOR1;1c in Arabidopsis wild type or in bor1-1 mutants promoted wild-type growth and rescued the bor1-1 mutant phenotype. Conversely, knockdown of BnaC4.BOR1;1c in a B-efficient rapeseed line reduced B accumulation in flower organs, eventually resulting in severe sterility and seed yield loss. BnaC4.BOR1;1c RNAi plants exhibited large amounts of disintegrated stigma papilla cells with thickened cell walls accompanied by abnormal proliferation of lignification under low-B conditions, indicating that the sterility may be a result of altered cell wall properties in flower organs. Taken together, our results demonstrate that BnaC4.BOR1;1c is a AtBOR1-homologous B transporter gene expressing in both roots and shoot nodes that is essential for the developing inflorescence tissues, which highlights its diverse functions in allotetraploid rapeseed compared with diploid model plant Arabidopsis. [ABSTRACT FROM AUTHOR]

A refrigeration system using phase change material (PCM) with six operating modes is proposed to reduce the cooling energy use of energy-demanding spaces such as data centers and telecommunication base stations. PCM is used to store the cold of outdoor air (OA) and/or that produced by vapor compression refrigeration (VCR) at night, and to release the stored energy for indoor cooling during the daytime. Real-time space cooling and cold charging by VCR can be accomplished simultaneously. Free cooling from OA can provide significant energy saving for space conditioning. A prototype system using a commercially available PCM was developed and tested to investigate the system performance and operation characteristics. The temperatures of air, water and refrigerant were measured along with the refrigerant pressure. The study calculates and analyzes the refrigerating capacity, cooling capacity, cold storage rate, supplied cold, stored cold, and the coefficient of performance (COP) upon the measurements. Experimental results indicate that the proposed refrigeration system can perform the requested tasks in a stable manner. The paper further compares the operating performances with the cold from OA and from VCR. It is found that under the outdoor temperature of 15 °C, OA appears to be more energy-efficient than VCR when the stored cold is less than 5.8 MJ, but it takes more time to charge the cold. [ABSTRACT FROM AUTHOR]

Traditional chemical looping technologies utilize solid oxygen carriers and has some disadvantages, especially when solid fuels like coal are used. In this work, a novel chemical looping process using gaseous metal oxide as oxygen carrier was proposed. The reaction of activated charcoal with gas-phase MoO 3 was studied for the first time. The experiments were conducted isothermally at different temperatures in a fixed-bed reactor. The apparent activation energy of the reaction was calculated and suitable kinetic models were determined. The results and analysis showed that the proposed concept has potential in both coal chemical looping combustion and gasification process. [ABSTRACT FROM AUTHOR]