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Global Navigation Satellite Systems (GNSS) tropospheric tomography is a commonly used technique for the reconstruction of three-dimensional water vapour field, and a priori vertical constraint models are required for water vapour density (WVD) determination which plays a critical role in the quality of tomographic results. However, generalised exponential models were routinely used for vertical constraints and limited research was carried out in the GNSS tomography by taking epoch-by-epoch variations into consideration. In this study, an adaptive four-dimensional (4-D) WVD model for the vertical constraints in GNSS tropospheric tomography was developed based on both ERA5 and surface meteorological data in Hong Kong for each month during the period of 2015–2019, and the back-propagation neural network technique was used to develop the fitting model. Then, the WVD model was used to obtain the WVD of adjacent voxels in the vertical direction to alleviate the mis-representation of the generalised exponential model. The newly developed WVD model used in GNSS tropospheric tomography was validated using GNSS data from the Hong Kong region in the year 2020 and two tomographic epochs (00:00–00:30 UTC and 12:00–12:30 UTC) were evaluated each day. For each topographic epoch, the WVDs of the tomographic voxels including radiosonde profile are evaluated (10 voxels over 10 height layers) using radiosonde data as the reference and the WVDs of all tomographic voxels are evaluated (300 voxels over 10 height layers) using ERA5 data as the reference. Results showed that when radiosonde/ERA5 data were utilized as the references, corresponding monthly mean values of the root mean square errors (RMSEs) in the entire year reduced from 1.97/1.94 g/m3 of the traditional tomographic method to 1.56/1.36 g/m3 of the new method which showed approximately 21/30% improvements. These results suggest a better performance of the tomographic approach using the new WVD model for the vertical constraints proposed by this study by taking epoch-by-epoch information. [ABSTRACT FROM AUTHOR]

Camouflaged object detection (COD) aims to accurately segment camouflaged objects blending into the environment and is a challenging task. Most existing deep learning-based COD methods do not explicitly enhance the region information of camouflaged objects, nor do they use the region information for mask calibration. To solve this issue, we propose a novel mask stepwise calibration network (MSCNet) for camouflaged object detection, which achieves high-precision detection of camouflaged objects. Specifically, MSCNet consists of a region information enhancement encoder and a mask stepwise calibration decoder. In the encoder, we first utilize a PVT backbone network to extract different levels of features from camouflaged images. Then, we design a region information enhancement module to enhance the region information of camouflaged objects while suppressing the interference of background information by mining, embedding, and aggregating the region information in different levels of features. In the decoder, we first design a coarse mask generation module to generate coarse prediction masks of camouflaged objects by directly cross-fusing different levels of features extracted by the backbone. In addition, we also design a mask calibration module to calibrate coarse prediction masks of camouflaged objects using the region information of different levels of camouflaged objects as a guide. Extensive experimental results on four benchmark datasets show that our method effectively identifies camouflaged objects and surpasses most state-of-the-art COD methods. [ABSTRACT FROM AUTHOR]

Microcracks are common in compact bone, but their continued propagation can lead to macroscopic fractures. These microcracks cannot be visualized radiographically, necessitating alternative noninvasive methods to identify excessive microcracking and prevent fractures. In this study, terahertz time-domain spectroscopy (THz-TDS) was used to examine bone interiors near cracks resulting from loading in bovine tibia samples. Various loading configurations, such as impact, quasi-static loading, and fatigue loading, known to induce different types of micro-scale damage, were applied. The values of refractive index and absorption coefficient of the bone samples were then determined from the THz-TDS spectra acquired before loading and after fracture. The study revealed that different loading configurations led to varying terahertz optical coefficients associated with various types of bone fractures. Specifically, the refractive index notably increased under fatigue loading but remained relatively stable during quasi-static bending. The absorption coefficient of bone decreased only under fatigue loading. Furthermore, samples were subjected to axial and radial impacts without sustaining damage. Results indicated that in the undamaged state, the change in refractive index was smaller compared to after impact failure, while the change in absorption coefficient remained consistent after failure. Under radial impact loading, changes in refractive index and absorption coefficient were significantly more pronounced than under axial loading. Prior to loading, the measured value of refractive index was 2.72 ± 0.11, and the absorption coefficient was 6.33 ± 0.09 mm−1 at 0.5 THz. [ABSTRACT FROM AUTHOR]

Based on the spatially correlated effects of air pollution on regional innovation, theoretical hypotheses are proposed, and this paper employs a spatial Durbin model to conduct empirical tests using panel data from 267 Chinese cities from 2003 to 2019, and investigates the mediating effect of human capital. Research has shown that (1) air pollution significantly reduces regional innovation output and has a negative spatial spillover effect significantly in the short term; (2) in the process of regional innovation impacted by air pollution, human capital acts as a mediator role; and (3) analysis of heterogeneity reveals that, from the regional perspective, air pollution has significantly damaged regional innovation in eastern and middle cities, but not significantly influences western cities, and in terms of innovation types, there is a stronger detrimental effect on invention patents exerted by air pollution compared to non-innovation patents. The study's findings provide theoretical and empirical evidence to strengthen environmental governance, enhance regional innovation and promote the coordinated development of regional innovation. [ABSTRACT FROM AUTHOR]

This study aims to assess the role of methotrexate-related gene polymorphisms in children with acute lymphoblastic leukemia (ALL) during high-dose methotrexate (HD-MTX) therapy and to explore their effects on serum metabolites before and after HD-MTX treatment. The MTHFR 677C>T, MTHFR 1298A>C, ABCB1 3435C>T, and GSTP1 313A>G genotypes of 189 children with ALL who received chemotherapy with the CCCG-ALL-2020 regimen from January 2020 to April 2023 were analyzed, and toxic effects were reported according to the Common Terminology Criteria for Adverse Events (CTCAE, version 5.0). Fasting peripheral blood serum samples were collected from 27 children before and after HD-MTX treatment, and plasma metabolites were analyzed by liquid chromatography-tandem mass spectrometry (LC–MS). The results of univariate and multivariate analyses showed that MTHFR 677C>T and ABCB1 3435 C>T gene polymorphisms were associated with the delayed MTX clearance (P < 0.05) and lower platelet count after treatment in children with MTHFR 677 mutation compared with wild-type ones (P < 0.05), and pure mutations in ABCB1 3435 were associated with higher serum creatinine levels (P < 0.05). No significant association was identified between MTHFR 677C>T, MTHFR 1298A>C, ABCB1 3435 C>T, and GSTP1 313A>G genes and hepatotoxicity or nephrotoxicity (P > 0.05). However, the serum metabolomic analysis indicated that the presence of the MTHFR 677C > T gene polymorphism could potentially contribute to delayed MTX clearance by influencing L-phenylalanine metabolism, leading to the occurrence of related toxic side effects. Conclusion: MTHFR 677C>T and ABCB1 3435 C>T predicted the risk of delayed MTX clearance during HD-MTX treatment in children with ALL. Serum L-phenylalanine levels were significantly elevated after HD-MTX treatment in children with the MTHFR 677C>T mutation gene. Trial registration: This study was registered at the Chinese Clinical Trial Registry (registration number: ChiCTR2000035264; registration: 2020/08/05; https://www.chictr.org.cn/). What is Known: • MTX-related genes play an important role in MTX pharmacokinetics and toxicity, but results from different studies are inconsistent and the mechanisms involved are not clear. What is New: • Characteristics, prognosis, polymorphisms of MTX-related genes, and metabolite changes were comprehensively evaluated in children treated with HD-MTX chemotherapy. • Analysis revealed that both heterozygous and pure mutations in MTHFR 677C>T resulted in a significantly increased risk of delayed MTX clearance, and that L-phenylalanine has the potential to serve as a predictive marker for the metabolic effects of the MTHFR 677C>T polymorphism. [ABSTRACT FROM AUTHOR]

With the deepening of the construction of the new type power system, the grid has become increasingly complex, and its safe and stable operation is facing more challenges. In order to improve the quality and efficiency of power grid management, State Grid Corporation continues to promote the digital transformation of the grid, proposing concepts such as cloud-edge-end collaborative architecture and power Internet of Things, for which comprehensive sensing of the grid is an important foundation. Power equipment is widely distributed and has a wide variety of types, and online monitoring of them involves the deployment and application of a large number of power sensors. However, there are various problems in implementing active power supplies for these sensors, which restrict their service life. In order to collect and utilize the vibration energy widely present in the grid to provide power for sensors, this paper proposes an electromagnetic vibration energy harvester and its design methodology based on a four-straight-beam structure, and carries out a trial production of prototype. The vibration pickup unit of the harvester is composed of polyimide cantilevers, a permanent magnet and a mass-adjusting spacer. The mass-adjusting spacer can control the vibration frequency of the vibration unit to match the target frequency. In this paper, a key novel method is proposed to increase the number of turns in a limited volume by stacking flexible coils, which can boost the output voltage of the energy harvester. A test system is built to conduct a performance test for the prototype harvester. According to the test results, the resonant frequency of the device is 100 H z , the output peak-to-peak voltage at the resonant frequency is 2.56 V at the acceleration of 1 g , and the maximum output power is around 151.7 μ W . The proposed four-straight-beam electromagnetic vibration energy harvester in this paper has obvious advantages in output voltage and power compared with state-of-the-art harvesters. It can provide sufficient power for various sensors, support the construction of cloud-edge-end architecture and the deployment of a massive number of power sensors. In the last part of this article, a self-powered transformer vibration monitor is presented, demonstrating the practicality of the proposed vibration energy harvester. [ABSTRACT FROM AUTHOR]

To provide a theoretical basis for the prevention and treatment of atherosclerosis (As), the current study aimed to investigate the mechanism underlying the effect of homocysteine (Hcy) on inducing the lipid deposition and foam cell formation of the vascular smooth muscle cell (VSMC) via C1q/Tumor necrosis factor-related protein9 (CTRP9) promoter region Hypermethylation negative regulating endoplasmic reticulum stress (ERs). Therefore, apolipoprotein E deficient (ApoE−/−) mice were randomly divided into the control [ApoE−/− + normal diet (NC)] and high methionine [ApoE−/− + (normal diet supplemented with 1.7% methionine (HMD)] groups (n = 6 mice/group). Following feeding for 15 weeks, the serum levels of Homocysteine (Hcy), total cholesterol (TC), and triglyceride (TG) were measured using an automatic biochemical analyzer. HE and oil red O staining were performed on the aorta roots to observe the pathological changes. Additionally, immunofluorescence staining was performed to detect the protein expression levels of CTRP9, glucose-regulated protein 78 kD (GRP78), phosphorylated protein kinase RNA-like ER kinase (p-PERK), activating transcription factor 6a (ATF6a), phosphorylated inositol-requiring enzyme-1α (p-IRE1α), sterol regulatory element binding proteins-1c (SREBP1c) and sterol regulatory element binding proteins-2 (SREBP2) in VSMC derived from murine aortic roots. In vitro, VSMC was stimulated with 100 μmol/l Hcy. After transfection of plasmids with overexpression and interference of CTRP9, ERs agonist (TM) and inhibitor (4-PBA) were given to stimulate VSMC cells. HE staining and oil red O staining were used to observe the effect of Hcy stimulation on lipid deposition in VSMC. Additionally, The mRNA and protein expression levels of CTRP9, GRP78, PERK, ATF6a, IRE1α, SREBP1c, and SREBP2 in VSMC were detected by RT-qPCR and western blot analysis, respectively. Finally, The methylation modification of the CTRP9 promoter region has been studied. The NCBI database was used to search the promoter region of the CTRP9 gene, and CpG Island was used to predict the methylation site. After Hcy stimulation of VSMC, overexpression of DNMT1, and intervention with 5-Azc, assess the methylation level of the CTRP9 promoter through bisulfite sequencing PCR (BSP). The results showed that the serum levels of Hcy, TC, and TG in the ApoE−/− + HMD group were significantly increased compared with the ApoE−/− + NC group. In addition, HE staining and oil red O staining showed obvious AS plaque formation in the vessel wall, and a large amount of fat deposition in VSMC, thus indicating that the hyperhomocysteinemia As an animal model was successfully established. Furthermore, CTRP9 were downregulated, while GRP78, p-PERK, ATF6a, p-IRE1α, SREBP1c, SREBP2 was upregulated in aortic VSMC in the ApoE−/− + HMD group. Consistent with the in vivo results, Hcy can inhibit the expression of CTRP9 in VSMC and induce ERs and lipid deposition in VSMC. Meanwhile, the increased expression of CTRP9 can reduce ERs and protect the lipid deposition in Hcy induced VSMC. Furthermore, ERs can promote Hcy induced VSMC lipid deposition, inhibition of ERs can reduce Hcy induced VSMC lipid deposition, and CTRP9 may play a protective role in Hcy induced VSMC lipid deposition and foam cell transformation through negative regulation of ERs. In addition, The CTRP9 promoter in the Hcy group showed hypermethylation. At the same time as Hcy intervention, overexpression of DNMT1 increases the methylation level of the CTRP9 promoter, while 5-Azc can reduce the methylation level of the CTRP9 promoter. Finally, Hcy can up-regulate the expression of DNMT1 and down-regulate the expression of CTRP9. After overexpression of DNMT1, the expression of CTRP9 is further decreased. After 5-Azc inhibition of DNMT1, the expression of DNMT1 decreases, while the expression of CTRP9 increases. It is suggested that the molecular mechanism of Hcy inhibiting the expression of CTRP9 is related to the hypermethylation of the CTRP9 promoter induced by Hcy and regulated by DNMT1. 5-Azc can inhibit the expression of DNMT1 and reverse the regulatory effect of DNMT1 on CTRP9. Overall, the results of the present study suggested that Hcy induces DNA hypermethylation in the CTRP9 promoter region by up-regulating DNMT1 expression, and negatively regulates ERs mediated VSMC lipid deposition and foam cell formation. CTRP9 may potentially be a therapeutic target in the treatment of hyperhomocysteinemia and As. [ABSTRACT FROM AUTHOR]

In industrial buildings, the presence of overhead cranes severely affects roof exhaust ventilation systems when capturing and discharging fumes, resulting in severe deterioration of the indoor plant environment. In this study, an overhead crane-based ventilation auxiliary device, called overhead crane fume-collecting hood (CFCH), is proposed to guide pollutants blocked by the overhead crane back to the roof exhaust hood. The airflow characteristics and pollutant distribution under the three modes of no overhead crane, overhead crane, and overhead crane + CFCH were compared using numerical simulations. Subsequently, the effects of the CFCH length (a), width (b), and height (h) on the pollutant capture performance were determined through orthogonal experiments and computational fluid dynamics. Finally, the pollutant capture efficiency (PCE) of the optimal CFCH was investigated considering different exhaust airflow rates. The results showed that the pollutants captured by the CFCH can be classified into directly and secondary captured pollutants, with the directly captured pollutants dominating. In addition, with the introduction of different sizes of CFCH around the overhead crane girders, the PCE significantly improved by 49.9%–74.6%. The length, width, and height of the CFCH on the PCE were statistically significant, and the priority of the three factors was as follows: h > b > a. The PCE decreased with increasing a, initially increased and then decreased with increasing b, and increased with h. Subsequently, when the optimal CFCH was used, the excessive exhaust air rate had no evident PCE improvement. This provides a new concept for the control of pollutants in industrial buildings and provides a theoretical basis for the design of CFCHs. [ABSTRACT FROM AUTHOR]

Based on the relationship between industrial agglomeration, green finance development, and carbon emissions, some relevant theoretical hypotheses are proposed, and this paper employs the combination of spatial Durbin model and panel threshold model to empirically test data from 30 provincial regions in China from 2006 to 2019. The results show that the agglomeration of high energy-consuming industries has an inverse U-curve relationship with carbon emission intensity, and the development of green finance will inhibit the growth of carbon emission intensity. There are significant spatial characteristics of high energy-consuming industrial agglomeration, green financial development, and carbon emissions. And the intensity of local carbon emissions will be influenced by the agglomeration of high energy-consuming industrial agglomeration and green financial development in local and neighboring areas. Moreover, green financial development plays a moderating role in the relationship between high energy-consuming industrial agglomeration and carbon emissions, and the role of high energy-consuming industrial agglomeration and green financial development on carbon emissions has a threshold effect due to the mismatch between the two developments. Under different levels of green financial development, the influence of high energy-consuming industrial agglomeration on carbon emissions varies widely, and green financial development helps to suppress the negative impact of high energy-consuming industrial agglomeration on carbon emissions. Accordingly, we argue that inter-regional joint prevention and control mechanism should be established for pollution control. And China should build more effective high energy-consuming industrial clusters to make them play an active role in reducing emissions. At the same time, China should accelerate the construction of green finance, strengthen the disclosure and transparency of green financial information, and establish a joint mechanism for the development of inter-regional green finance, so that it can contribute to regional industrial transformation and pollution control. [ABSTRACT FROM AUTHOR]

Developing efficient catalysts is of paramount importance to oxygen evolution, a sluggish anodic reaction that provides essential electrons and protons for various electrochemical processes, such as hydrogen generation. Here, we report that the oxygen evolution reaction (OER) can be efficiently catalyzed by cobalt tetrahedra, which are stabilized over the surface of a Swedenborgite-type YBCo4O7 material. We reveal that the surface of YBaCo4O7 possesses strong resilience towards structural amorphization during OER, which originates from its distinctive structural evolution toward electrochemical oxidation. The bulk of YBaCo4O7 composes of corner-sharing only CoO4 tetrahedra, which can flexibly alter their positions to accommodate the insertion of interstitial oxygen ions and mediate the stress during the electrochemical oxidation. The density functional theory calculations demonstrate that the OER is efficiently catalyzed by a binuclear active site of dual corner-shared cobalt tetrahedra, which have a coordination number switching between 3 and 4 during the reaction. We expect that the reported active structural motif of dual corner-shared cobalt tetrahedra in this study could enable further development of compounds for catalyzing the OER. Efficient oxygen evolution relies on the development of promising catalysts. Herein, the authors demonstrate that cobalt tetrahedra, stabilized over the surface of YBCo4O7 material, can catalyze oxygen evolution reaction efficiently. [ABSTRACT FROM AUTHOR]

The structural origins of bone toughness at the nanoscale are not completely understood. Therefore, we performed in situ scanning using atomic force microscopy during macroscopic mechanical testing of antler and bovine bone, to reveal the origins of the irreversible plastic deformation at the mineralized collagen fibril (MCF) array and MCF levels. We found that the plastic deformation behavior at the nanoscale level could be divided into two stages. The first stage of plastic deformation at the nanoscale level was characterized by slippage between the MCF arrays, which contained mineral aggregate grains with regular shapes under load. In the second stage of nanoscale plastic deformation, the MCFs broke through the bonds of the extrafibrillar mineral aggregate grains and exhibited interfibrillar slippage. These nanoscale plastic deformation behaviors may thus be the origins of stress whitening and irreversible plastic deformation. Thus, the findings in this study not only shed light on the plastic deformation mechanisms of MCF arrays and MCFs, but also provide structural and mechanistic insights into bioinspired materials design and mechanisms of relevant bone diseases. [ABSTRACT FROM AUTHOR]

To reveal the molecular mechanism in the accumulation of chlorogenic acids (CGAs) in peach (Prunus persica) fruit during growth and development, CGA contents in the flesh of the three peach cultivars 'Ruiguang 18', 'Heiyoutao', and 'Beijingyixianhong' were determined. The expression levels of CGA metabolism-related genes were analyzed based on transcriptome data (RNA-seq). These candidate genes were then screened and real-time fluorescent quantitative PCR (qRT-PCR) was performed to verify their expression. The results showed that the content of total CGAs, 5-O-caffeoylquinic acid and 3-O-caffeoylquinic acid, in the flesh of 'Ruiguang 18' exhibited a decreasing trend during fruit development, and there was a great drop at maturity stage (P < 0.05). The three contents in 'Heiyoutao' increased first at stage S2 (P < 0.05) and then decreased significantly (P < 0.05). In 'Beijingyixianhong', they stayed stable in the early stages, then total CGAs and 3-O-caffeoylquinic acid decreased significantly at the maturity stage (P < 0.05). RNA-seq transcriptome data analysis and qRT-PCR expression analysis showed that the accumulation of CGAs in fruit flesh was mainly affected by the expression of Prupe.3G100800 (PpHCT) and Prupe.3G107300 (Pp4CL), and their expression levels were highly consistent with total CGA content. Thus, we concluded that Prupe.3G100800 (PpHCT) and Prupe.3G107300 (Pp4CL) are the key genes for CGAs synthesis in peach flesh. [ABSTRACT FROM AUTHOR]

The microbiota modulates gut immune homeostasis. Bacteria influence the development and function of host immune cells, including T helper cells expressing interleukin-17A (TH17 cells). We previously reported that the bile acid metabolite 3-oxolithocholic acid (3-oxoLCA) inhibits TH17 cell differentiation1. Although it was suggested that gut-residing bacteria produce 3-oxoLCA, the identity of such bacteria was unknown, and it was unclear whether 3-oxoLCA and other immunomodulatory bile acids are associated with inflammatory pathologies in humans. Here we identify human gut bacteria and corresponding enzymes that convert the secondary bile acid lithocholic acid into 3-oxoLCA as well as the abundant gut metabolite isolithocholic acid (isoLCA). Similar to 3-oxoLCA, isoLCA suppressed TH17 cell differentiation by inhibiting retinoic acid receptor-related orphan nuclear receptor-γt, a key TH17-cell-promoting transcription factor. The levels of both 3-oxoLCA and isoLCA and the 3α-hydroxysteroid dehydrogenase genes that are required for their biosynthesis were significantly reduced in patients with inflammatory bowel disease. Moreover, the levels of these bile acids were inversely correlated with the expression of TH17-cell-associated genes. Overall, our data suggest that bacterially produced bile acids inhibit TH17 cell function, an activity that may be relevant to the pathophysiology of inflammatory disorders such as inflammatory bowel disease.Bacterially produced bile acids inhibit TH17 cell function, which may be relevant to the pathophysiology of inflammatory disorders such as inflammatory bowel disease. [ABSTRACT FROM AUTHOR]

Normally, preslaughter acute heat stress could accelerate postmortem glycolysis and impair chicken breast (pectoralis major muscle) quality. However, previous studies indicated that it might be different when the acute heat stress temperature rises to an extreme range (above 35 °C). Therefore, this study's objectives were to compare the pH decline, glycolytic enzyme activity, and AMP-activated protein kinase (AMPK) phosphorylation at early postmortem among three extreme acute heat stress temperature settings: a control group (36 °C) and two experimental groups (38 °C and 40 °C). Although the temperature did not affect glycogen phosphorylase a and pyruvate kinase activity, there was a decrease in pH decline rate, phosphofructokinase-1 activity, and phospho-AMPK-α[Thr172] within 4 h postmortem when temperature increased from 36 to 40 °C. Temperature also affected hexokinase activity, with the 36 °C-group having the highest activity. The results of the current study, for the first time, indicated that postmortem metabolic rate in chicken breast muscle could be changed by acute heat stress temperature setting at extreme range. [ABSTRACT FROM AUTHOR]

Lycium barbarum polysaccharide (LBP) is an alkaloid extracted from lycium barbarum. LBP is the active component of lycium barbarum used to treat hypertension, atherosclerosis and other cardiovascular diseases in Chinese traditional medicine. However, the underlying cellular and molecular mechanisms of LBP- mediated activity in vascular disease remain poorly understood. In the present study, we showed the protective effect of LBP in vascular smooth muscle cells. Our results indicate that LBP significantly reduces the proliferation of VSMCs caused by Homocysteine (Hcy) and inhibits the phenotypic transformation of VSMCs caused by Hcy, from contractile to synthetic. LBP inhibited the protein expression of PI3K and Akt caused by Hcy, and increased the expression of miR-145. The results indicate that LBP exhibits substantial therapeutic potential for the treatment of Hcy-induced VSMCs proliferation and phenotypic transformation through inhibition of PI3K/Akt signaling pathway. [ABSTRACT FROM AUTHOR]

During the summer, high ambient temperature and humidity cause economic loss to the global livestock industry via reduced livestock productivity and increased mortality. The problem of heat stress (HS) is likely to be exacerbated by global warming and climate change. Recent research has shown that HS not only leads to physiological and metabolic perturbations in live animals but can also affect carcass and meat quality characteristics plausibly by altering the rate and extent of postmortem muscle glycolysis and resultant pH. However, these impacts of HS are not consistent across species. Higher incidence of pale soft and exudative (PSE) meat has been reported in poultry. On the contrary, higher incidence of high ultimate pH and dark firm and dry (DFD) meat or no impacts of HS have been reported in sheep and cattle. With the limited data on HS impacts on meat quality of ruminants, it is difficult to explain the exact mechanisms driving these variable impacts. However, it is hypothesized that the severity and duration of HS may lead to variable impacts due to lack of opportunity to adapdate to acute heat exposure. Longer HS exposure may allow ruminants to adapdate to heat and may not record any negative impacts on meat quality. This paper reviews the recent research on impacts of HS on meat quality characteristics and identify the key areas of further research required to better understand these negative impacts to develop strategies for amelioration. In addition, some mitigation strategies of HS have also been discussed which include both managemental and nutritional interventions. [ABSTRACT FROM AUTHOR]

The proliferation, migration, and cellular morphology of vascular smooth muscle cells (VSMCs) play important roles in the pathogenesis of atherosclerosis (AS). Homocysteine (Hcy) is a sulfur-containing amino acid, which is an intermediate product of methionine metabolism. Hcy can induce proliferation, migration, and phenotypic switch of VSMCs, but details of these mechanisms are still unclear. The phosphatidylinositol 3-kinase (PI3K/Akt/mTOR) signaling pathway is involved in a host of cellular functions. In this study, we sought to determine if this multifunctional pathway played a role in Hcy-induced proliferation, migration, and phenotypic transformation of VSMCs, which has not been previously reported. miR-145 has been previously reported to suppress the effects of Hcy in VSMCs. In our study, using qRT-PCR, we found that Hcy itself reduced the expression of miR-145 in VSMCs, while overexpression of miR-145 reduced the proliferation, migration, and phenotypic transformation of VSMCs caused by Hcy. Using Western blot analysis, we found that VSMCs exposed to Hcy exhibited significant increases in the levels of PI3K, Akt, and mTOR proteins. Additionally, overexpression of miR-145 dramatically decreased PI3K, Akt, and mTOR expression. Using qRT-PCR we found that miR-145 expression increased after blocking PI3K using an inhibitor. Inhibition of the PI3K signaling pathway also prevented Hcy-induced VSMC proliferation, migration, and phenotypic switch. Taken together, our results suggest that miR-145 could inhibit VSMC proliferation, migration, and phenotype switching by preventing activation of the PI3K/Akt/mTOR signaling pathway. [ABSTRACT FROM AUTHOR]

An ideal wound dressing is highly desired for the repair of chronic wounds which should provide a moist environment, self-healing, antibacterial properties etc. Here, a novel injectable antibacterial chitosan hydrogel with good self-healing and improved mechanical properties has been prepared by dialdehyde bacterial cellulose (DABC) nanofibers as the non-toxic biocrosslinker. It is the first time to prepare the all-natural chitosan hydrogels by using ascorbic acid (VC) as solvent to dissolve chitosan and the natural fiber DABC as reinforcing and crosslinking agent. Then, the disadvantage of the use of acetic acid in the medical field was overcome and the other toxic crosslinking agents were abandoned. Accordingly, this work provides a new strategy towards fabricating the self-healing hydrogel with injectable and antibacterial properties. The new multifunctional hydrogels demonstrate strong potentiality in wound dressings or tissue engineering. [ABSTRACT FROM AUTHOR]

This work reports a comprehensive study of a novel polyol method that can successfully synthesize layered LiNi0.4Mn0.4Co0.2O2, spinel LiNi0.5Mn1.5O4, and olivine LiCoPO4 cathode materials. When properly designed, polyol method offers many advantages such as low cost, ease of use, and proven scalability for industrial applications. Most importantly, the unique properties of polyol solvent allow for greater morphology control as shown by all the resulting materials exhibiting monodispersed nanoparticles morphology. This morphology contributes to improved lithium ion transport due to short diffusion lengths. Polyol-synthesized LiNi0.4Mn0.4Co0.2O2 delivers a reversible capacity of 101 and 82 mAh·g−1 using high current rate of 5C and 10C, respectively. It also displays surprisingly high surface structure stability after charge-discharge processes. Each step of the reaction was investigated to understand the underlying polyol synthesis mechanism. A combination of in situ and ex situ studies reveal the structural and chemical transformation of Ni-Co alloy nanocrystals overwrapped by a Mn- and Li-embedded organic matrix to a series of intermediate phases, and then eventually to the desired layered oxide phase with a homogeneous distribution of Ni, Co, and Mn. We envisage that this type of analysis will promote the development of optimized synthesis protocols by establishing links between experimental factors and important structural and chemical properties of the desired product. The insights can open a new direction of research to synthesize high-performance intercalation compounds by allowing unprecedented control of intermediate phases using experimental parameters. [ABSTRACT FROM AUTHOR]

Lithium metal anodes offer high theoretical capacities (3,860 milliampere-hours per gram)1, but rechargeable batteries built with such anodes suffer from dendrite growth and low Coulombic efficiency (the ratio of charge output to charge input), preventing their commercial adoption2,3. The formation of inactive ('dead') lithium— which consists of both (electro)chemically formed Li+ compounds in the solid electrolyte interphase and electrically isolated unreacted metallic Li0 (refs 4,5)—causes capacity loss and safety hazards. Quantitatively distinguishing between Li+ in components of the solid electrolyte interphase and unreacted metallic Li0 has not been possible, owing to the lack of effective diagnostic tools. Optical microscopy6, in situ environmental transmission electron microscopy7,8, X-ray microtomography9 and magnetic resonance imaging10 provide a morphological perspective with little chemical information. Nuclear magnetic resonance11, X-ray photoelectron spectroscopy12 and cryogenic transmission electron microscopy13,14 can distinguish between Li+ in the solid electrolyte interphase and metallic Li0, but their detection ranges are limited to surfaces or local regions. Here we establish the analytical method of titration gas chromatography to quantify the contribution of unreacted metallic Li0 to the total amount of inactive lithium. We identify the unreacted metallic Li0, not the (electro)chemically formed Li+ in the solid electrolyte interphase, as the dominant source of inactive lithium and capacity loss. By coupling the unreacted metallic Li0 content to observations of its local microstructure and nanostructure by cryogenic electron microscopy (both scanning and transmission), we also establish the formation mechanism of inactive lithium in different types of electrolytes and determine the underlying cause of low Coulombic efficiency in plating and stripping (the charge and discharge processes, respectively, in a full cell) of lithium metal anodes. We propose strategies for making lithium plating and stripping more efficient so that lithium metal anodes can be used for next-generation high-energy batteries. Titration gas chromatography is developed as an analytical method of distinguishing between lithium metal and lithium compounds within a cycled battery and assessing the amount of unreacted metallic lithium available. [ABSTRACT FROM AUTHOR]

Abstract: To construct a biomimetic scaffold with a nanoscale structure similar to that of natural tissue, the objective of this work was to prepare three-dimensional (3D) porous hybrid scaffolds based on gelatin and bacterial cellulose nanofibers for tissue regeneration. The nanofibrous structure, water absorption, and compressive mechanical properties of the scaffolds were studied. The hybrid scaffolds not only give a sufficiently porous structure for efficient nutrient transport and vascularization, but also provide the nanofibrous structure and improve the roughness of the scaffold pore walls. The hybrid scaffolds also exhibit higher modulus as stiffness compared to the pure gelatin scaffold. The viability and morphology of Pig iliac endothelial cells (PIECs) cultured on the 3D scaffolds were examined. PIECs adhered and proliferated better on the stiff hybrid scaffold with nanofibers compared to the soft gelatin scaffold without nanofibers. The results addressed the effect of the nanofibers and the stiffness of scaffolds on cell behavior, and the biomimetic nanofibrous hybrid scaffolds would be highly favorable/desired for tissue regeneration, e.g., skin and urethral regeneration.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Abstract: Hypertrophic scar (HS) is a kind of fibroproliferative disorder with gross and inordinate fiber bundles twisted in the deep scar and it often occurs after deep dermal injury. In this paper, bacterial cellulose (BC), a good candidate for wound dressing, was modified with a stripe pattern by a simple static culture method using patterned PDMS templates in order to investigate the inhibition of cicatricial contractions. The obtained patterned bacterial celluloses (pBC) with different sizes were characterized by optical microscopy and field emission scanning electron microscopy. Different nanofiber structures were observed in bulges and depressions, indicating different cell behaviors on the pBC. In vitro experiments demonstrated that L929 cells showed a clear stripe distribution. Moreover, pBC had an obvious inhibitory effect on L929 cells proliferation, especially pBC with 10 μm stripes which was close to the size of the cells. Furthermore, in vivo experiments of injury model demonstrated that pBC effectively inhibited inflammatory response, reduced accumulation of fibroblasts, and significantly decreased the scar contraction compared to the control and standard groups, indicating its good HS inhibition effect. Compared with that for unmodified BC, the scar thickness for the pBC wound dressing significantly decreased from 428.7 ± 61.9 to 261.5 ± 89.6 µm, which was at least two times less than that of the standard and blank control groups. Excitingly, it was found that if the width of the stripes matched the size of the cell, the pBC had better anti-scar effect, which can also be extended to other dressings.Graphical Abstract: [ABSTRACT FROM AUTHOR]

The Wagner coefficient is a key parameter used to describe the inelastic lateral-torsional buckling (LTB) behaviour of the I-beam, since even for a doubly-symmetric I-section with residual stress, it becomes a monosymmetric I-section due to the characteristics of the non-symmetrical distribution of plastic regions. However, so far no theoretical derivation on the energy equation and Wagner’s coefficient have been presented due to the limitation of Vlasov’s buckling theory. In order to simplify the nonlinear analysis and calculation, this paper presents a simplified mechanical model and an analytical solution for doubly-symmetric I-beams under pure bending, in which residual stresses and yielding are taken into account. According to the plate-beam theory proposed by the lead author, the energy equation for the inelastic LTB of an I-beam is derived in detail, using only the Euler-Bernoulli beam model and the Kirchhoff-plate model. In this derivation, the concept of the instantaneous shear centre is used and its position can be determined naturally by the condition that the coefficient of the cross-term in the strain energy should be zero; formulae for both the critical moment and the corresponding critical beam length are proposed based upon the analytical buckling equation. An analytical formula of the Wagner coefficient is obtained and the validity of Wagner hypothesis is reconfirmed. Finally, the accuracy of the analytical solution is verified by a FEM solution based upon a bi-modulus model of I-beams. It is found that the critical moments given by the analytical solution almost is identical to those given by Trahair’s formulae, and hence the analytical solution can be used as a benchmark to verify the results obtained by other numerical algorithms for inelastic LTB behaviour. [ABSTRACT FROM AUTHOR]

The authors describe a signal amplification strategy for highly sensitive detection of the prostate-specific antigen (PSA). This is accomplished by a combination of two methods, viz. (a) improved surface-initiated enzymatic polymerization (SIEP), and (b) the use of nanoflowers prepared from C fullerene and Methylene Blue (C/MB) modified with a long single-strand DNA. C/MB acts as a novel electrochemical indicator. The C/MB nanoflowers improve the load of MB and promote the electron transfer. The integration of the SIEP technique and the C/MB nanomaterial also results in improved loading of MB on the nucleic acid. Ultimately, dual cascade signal amplification is accomplished. The biosensor was constructed as follows: (a) Gold nanospheres were modified with antibody 2 (Ab) and a thiolated oligonucleotide (referred to as S). (2) S is then extended by the SIEP reaction. (3) The redox indicator C/MB is then connected to the extended guanine-rich ssDNA which then yields the amperometric signal. (4) A sandwich immunoassay is performed by capturing the nanoprobe oy type Ab-Au-S on the gold electrode modified with multi-walled carbon nanotubes (MWCNTs) and protein A. Current is measured by using differential pulse voltammetry (DPV). The synergic effect of the biofunctional nanomaterial and the signal amplification strategy greatly improves the performance of this immunoassay. Under optimized conditions and at a working voltage of typically −0.18 V (vs Ag/AgCl), the assay has a linear range that extends from 15 pg·mL to 8 ng·mL of PSA. The detection limit is as low as 1.7 pg·mL (at an S/N ratio of 3). In our perception, this dual amplification scheme has a wide scope in that it may become applicable to numerous other immunoassays. [ABSTRACT FROM AUTHOR]

Transforming growth factor-β1 (TGFβ1) plays a significant role in regulating cellular proliferation and apoptosis. A large number of studies related to the association between TGFβ1 Leu10Pro polymorphism and prostate cancer (PC) risk, but get conflicting results. We performed a meta-analysis based on six studies, assessing the strength of the association using odds ratios (OR) with 95 % confidence intervals (CI). Overall, our evidence has indicated that TGFβ1 Leu10Pro polymorphism had significantly increased PC risk in the allele comparison model (OR = 1.081, 95 % CI = 1.003-1.165, P = 0.141, P = 0.041). In the stratified analysis by ethnicity, the same results were found among Caucasians (for heterozygote model, OR = 1.741, 95 % CI = 1.004-3.020, P = 0.000, P = 0.049; recessive model, OR = 1.339, 95 % CI = 1.045-1.717, P = 0.020, P = 0.021; allele comparison model, OR = 1.091, 95 % CI = 1.005-1.184, P = 0.048, P = 0.037). In conclusion, this meta-analysis suggested that TGFβ1 Leu10Pro polymorphism contributed to the development of PC. A well-designed and larger study is still required to evaluate this polymorphism and PC risk. [ABSTRACT FROM AUTHOR]

The innate immune system provides the first line of host defence against invading pathogens. Key to upregulation of the innate immune response are Toll-like receptors (TLRs), which recognize pathogen-associated molecular patterns (PAMPs) and trigger a signaling pathway culminating in the production of inflammatory mediators. Central to this TLR signaling pathway are heterotypic protein-protein interactions mediated through Toll/interleukin-1 receptor (TIR) domains found in both the cytoplasmic regions of TLRs and adaptor proteins. Pathogenic bacteria have developed a range of ingenuous strategies to evade the host immune mechanisms. Recent work has identified a potentially novel evasion mechanism involving bacterial TIR domain proteins. Such domains have been identified in a wide range of pathogenic bacteria, and there is evidence to suggest that they interfere directly with the TLR signaling pathway and thus inhibit the activation of NF-κB. The individual TIR domains from the pathogenic bacteria Salmonella enterica serovar Enteritidis, Brucella sp, uropathogenic E. coli and Yersinia pestis have been analyzed in detail. The individual bacterial TIR domains from these pathogenic bacteria seem to differ in their modes of action and their roles in virulence. Here, we review the current state of knowledge on the possible roles and mechanisms of action of the bacterial TIR domains. [ABSTRACT FROM AUTHOR]