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Photo-fermentative hydrogen production, the new energy production alternative, was greatly enhanced by formed biofilm. To understand the mechanism of enhancement, the intracellular proteome and extracellular polymeric substance (EPS)ii EPS: extracellular polymeric substanceiiPFHP: Photo-fermentative hydrogen productioniiiPFB: photo-fermentative bacteriaivQS: quorum sensingvCLSM: Confocal laser scanning microscopyviCR: Control reactorviiBR: Biofilm reactorviiiTEM: Transmission electron microscopeixXPS: X-ray photoelectron spectroscopyxFTIR: Fourier transform infrared spectroscopyxiSM: Supplementary materialsxiiDEPs: Differentially expressed proteinsxiiiTCA cycle: Tricarboxylic acid cyclexivGO: Gene ontologyxvKEGG: Kyoto encyclopedia of genes and genomes during biofilm formation were investigated in this work. Experimental results indicated that a possible and effective altered system could transfer light to hydrogen. Proteins were significantly regulated, for example those related with nitrogenase, flagellin, EPS transportation and DNA duplication were up-regulated while those concerned photosystem were down-regulated. It revealed these changes of proteins contributed to positive activity of key enzymes, improved communication system and increased total light utilization efficiency thus leading to enhanced capacity of hydrogen production. Besides above metabolic changes inside the cells, EPS secreted by the bacteria played an important role in hydrogen production and its yield decided the release of hydrogen. When EPS descended to a lower concentration during biofilm formation, it meant carbon source for EPS synthesis was reduced, and more energy and reducing power could be transferred into hydrogen energy. More importantly, this work found that composition and structure of EPS were efficiently influenced by the formation of biofilm, such as benzene and O-H structure, secondary protein structure and the kinds of protein, which were important to stable biofilm and efficient hydrogen production. Therefore, final hydrogen yield was improved by altered protein and EPS resulted from biofilm formation. This study demonstrated that formation of biofilm is an efficient, ecological and attracting way to the future bio-hydrogen production.

Background: Cap-assisted endoscopic sclerotherapy is a new interventional therapy for internal hemorrhoids and rectal prolapse under colonoscopy. The proper length of the endoscopic injection needle is the core for performing cap-assisted endoscopic sclerotherapy well with more benefits and less complications. However, no data are currently available to guide endoscopists to consider the length of injection needle before cap-assisted endoscopic sclerotherapy. This study is designed to evaluate the efficacy and safety of cap-assisted endoscopic sclerotherapy with long or short injection needle in the treatment of internal hemorrhoids. Methods: This is a nationwide multi-center, prospective, single-blind and randomized controlled trial. Patients with grade I-II internal hemorrhoids who have failed to conservative treatments and grade III internal hemorrhoids who are not suitable for surgery or refuse surgery will be included. Participants will be randomized 1:1 into either long or short injection needle group. The primary outcome is the recurrence rate of internal hemorrhoids 24 weeks after cap-assisted endoscopic sclerotherapy. The secondary outcomes are as follows: (1) symptom severity score, (2) three-level EuroQoL five dimensions health scale scores, (3) occurrence of adverse events and severe adverse events, and (4) patients’ attitudes toward cap-assisted endoscopic sclerotherapy. Data collection will be conducted before and during operation, the 1st day, 1st week, 2nd week, and 24th week after cap-assisted endoscopic sclerotherapy. Discussion: The outcome of this study is expected to provide a practical clinical protocol of cap-assisted endoscopic sclerotherapy for patients with internal hemorrhoids and promote the use of this new endoscopic technique. Trial registration: ClinicalTrials.gov, NCT03917056. Registered on 12 April 2019.

Complex animal behaviors arise from a flexible combination of stereotyped motor primitives. Here we use the escape responses of the nematode Caenorhabditis elegans to study how a nervous system dynamically explores the action space. The initiation of the escape responses is predictable: the animal moves away from a potential threat, a mechanical or thermal stimulus. But the motor sequence and the timing that follow are variable. We report that a feedforward excitation between neurons encoding distinct motor states underlies robust motor sequence generation, while mutual inhibition between these neurons controls the flexibility of timing in a motor sequence. Electrical synapses contribute to feedforward coupling whereas glutamatergic synapses contribute to inhibition. We conclude that C. elegans generates robust and flexible motor sequences by combining an excitatory coupling and a winner-take-all operation via mutual inhibition between motor modules.

Blazed gratings are the critical dispersion elements in spectral analysis instruments, whose performance depends on structural parameters and topography of the grating groove. In this paper, high diffraction efficiency silicon-blazed grating working at 800–2500 nm has been designed and fabricated. By diffraction theory analysis and simulation optimization based on the accurate boundary integral equation method, the blaze angle and grating constant are determined to be 8.8° and 4 μm, respectively. The diffraction efficiency is greater than 33.23% in the spectral range of 800–2500 nm and reach the maximum value of 85.62% at the blaze wavelength of 1180 nm. The effect of platform and fillet on diffraction efficiency is analyzed, and the formation rule and elimination method of the platform are studied. The blazed gratings are fabricated by anisotropic wet etching process using tilted (111) silicon substrate. The platform is minished by controlling etching time and oxidation sharpening process. The fillet radius of the fabricated grating is 50 nm, the blaze angle is 7.4°, and the surface roughness is 0.477 nm. Finally, the blazed grating is integrated in scanning micromirror to form scanning grating micromirror by MEMS fabrication technology, which can realize both optical splitting and scanning. The testing results show that the scanning grating micromirror has high diffraction efficiency in the spectral range of 810–2500 nm for the potential near-infrared spectrometer application.

Aramid fiber-reinforced plastic (AFRP) composites are widely used in aerospace, rail transit, marine and military industries, due to their high specific strength, high impact resistance, fatigue resistance and excellent designable properties. In order to meet different application requirements, cutting processes need to be carried out, such as window opening, edge cutting and slit cutting. However, the characteristics of high tensile strength and toughness, low interlaminar strength, non-uniformity and anisotropy make AFRP composites a difficult-to-machine material. They are prone to produce rough cutting surfaces and cutting damages including burr, wire drawing, delamination, resin burn, material flanging, etc. To solve this problem, the ultra-thin diamond dicing blade was used for high-speed cutting of AFRP composites in sub-fiber scale in this research. The influence of process parameters on cutting force, cutting temperature, maximum spindle current, tool wear and cutting surface quality were investigated by establishing the cutting force model, L16(45) orthogonal experiment, single factor experiment, range analysis and variance analysis. The theoretical and experimental results show that cutting AFRP composites with ultra-thin diamond dicing blade can obtain smooth surfaces without common cutting damages. When the cutting speed is 91.11 m/s (spindle speed n = 30,000 r/min), the cutting depth is 0.2 mm and the feed speed is 5 mm/s, the surface roughness Ra can be as low as 32 nm, which realize the precision cutting of AFRP composites.

As one of the effective renewable energy sources, wind energy has received attention because it is sustainable energy. Accurate wind speed forecasting can pave the way to the goal of sustainable development. However, current methods ignore the temporal characteristics of wind speed, which leads to inaccurate forecasting results. In this paper, we propose a novel SSA-CCN-ATT model to forecast the wind speed. Specifically, singular spectrum analysis (SSA) is first applied to decompose the original wind speed into several sub-signals. Secondly, we build a new deep learning CNN-ATT model that combines causal convolutional network (CNN) and attention mechanism (ATT). The causal convolutional network is used to extract the information in the wind speed time series. After that, the attention mechanism is employed to focus on the important information. Finally, a fully connected neural network layer is employed to get wind speed forecasting results. Three experiments on four datasets show that the proposed model performs better than other comparative models. Compared with different comparative models, the maximum improvement percentages of MAPE reaches up to 26.279%, and the minimum is 5.7210%. Moreover, a wind energy conversion curve was established by simulating historical wind speed data.

Abstract Background Hepatocyte transplantation has been proposed as an effective treatment for patients with acute liver failure (ALF), but its application is limited by a severe shortage of donor livers. Human pluripotent stem cells (hPSCs) have emerged as a potential cell source for regenerative medicine. Human amniotic epithelial stem cells (hAESCs) derived from amniotic membrane have multilineage differentiation potential which makes them suitable for possible application in hepatocyte regeneration and ALF treatment. Methods The pluripotent characteristics, immunogenicity, and tumorigenicity of hAESCs were studied by various methods. hAESCs were differentiated to hepatocyte-like cells (HLCs) using a non-transgenic and three-step induction protocol. ALB secretion, urea production, periodic acid-Schiff staining, and ICG uptake were performed to investigate the function of HLCs. The HLCs were transplanted into ALF NOD-SCID (nonobese diabetic severe combined immunodeficient) mouse, and the therapeutic effects were determined via liver function test, histopathology, and survival rate analysis. The ability of HLCs to engraft the damaged liver was evaluated by detecting the presence of GFP-positive cells. Results hAESCs expressed various markers of embryonic stem cells, epithelial stem cells, and mesenchymal stem cells and have low immunogenicity and no tumorigenicity. hAESC-derived hepatocytes possess the similar functions of human primary hepatocytes (hPH) such as producing urea, secreting ALB, uptaking ICG, storing glycogen, and expressing CYP enzymes. HLC transplantation via the tail vein could engraft in live parenchymal, improve the liver function, and protect hepatic injury from CCl4-induced ALF in mice. More importantly, HLC transplantation was able to significantly prolong the survival of ALF mouse. Conclusion We have established a rapid and efficient differentiation protocol that is able to successfully generate ample functional HLCs from hAESCs, in which the liver injuries and death rate of CCl4-induced ALF mouse can be significantly rescued by HLC transplantation. Therefore, our results may offer a superior approach for treating ALF.

AIM: To evaluate the clinical effect of bevacizumab in pterygium treatment. METHODS: A systematic review and quantitative Meta-analysis was performed. PubMed, EMBASE, Web of Science and Cochrane database were searched for eligible literatures published in English until June 2016. The endpoint was recurrence rate and pooled risk ratio (RR) was calculated. RESULTS: Nine eligible studies were included and Meta-analysis results showed no significantly difference in patients treated with bevacizumab in short term follow-up [3mo: RR=0.70 (0.34, 1.45); 6mo: RR=0.55 (0.23, 1.32)] compared with control groups. No significant effects were observed in favor of bevacizumab in subgroup analyses: patients with subconjunctival injection of bevacizumab [3mo: RR=0.95 (0.70, 1.29); 6mo: RR=0.83 (0.55, 1.28)], primary pterygium [3mo: RR=0.59 (0.23, 1.54; 6mo: RR=0.59 (0.23, 1.53)], simple pterygium excision [3mo: 0.32 (0.05, 2.04), P=0.23; 6mo: 0.27 (0.05, 1.53)] and excision with conjunctival autograft [3mo: 1.51 (0.25, 9.15); 6mo: 1.11 (0.06, 21.69)]. CONCLUSION: In this Meta-analysis, we did not found the significant effect of bevacizumab in pterygium treatment, at least in short term follow-up (3mo and 6mo).

Abstract Background We aimed to investigate the effect of early-life diverse microbial exposures on gut microbial colonization in an OVA-induced asthma model in BALB/c mice. Methods BALB/c mice were divided into 4 groups: A, offsprings were kept in a SPF environment during fetal, lactation, and childhood periods; B, offsprings were kept in the SPF environment during fetal and lactation periods, and kept in the general environment during childhood; C, offsprings were kept in the SPF environment only during fetal period, and then kept in the general environment; and D, offsprings were kept in the general environment during whole periods. The diversity of intestinal flora was analyzed using denaturing gradient gel electrophoresis. Mice were sensitized with OVA to establish an animal model of asthma. Then asthma-related inflammatory cytokines and histological analysis were performed. Results The diversity of intestinal microflora in group D was significantly higher than groups A, B and C at three days and three weeks after birth, and the diversity of intestinal microflora in groups C and D were significantly higher than groups A and B at five weeks after birth. The pathologic scores of OVA-induced asthmatic mice in group D were significantly lower than group A, and serum IFN-γ levels and the IFN-γ/IL-4 ratio in group D were significantly higher than group A. Conclusions Exposure to diverse microbial environments in early life affects gut microbial colonization in BALB/c mice. The diversity of the intestinal flora in early life may prevent airway inflammation in asthma via regulating the Th1/Th2 balance.

The strength, toughness, and fatigue crack growth (FCG) resistance of high‐strength steels are the key performance indexes concerned in the material selection of engineering components. It is considered that the FCG resistance of high‐strength steels can be optimized by simultaneous strengthening and toughening. In order to make clear whether the above view is correct or not, the strength–toughness combination and FCG resistance of AISI 4340 steel under different heat treatments are investigated and compared with those of 18Ni maraging steel in the present study. Meanwhile, the major fatigue damage mechanism of the AISI 4340 steel is analyzed and discussed. It is found that the FCG resistance of AISI 4340 steel enhances rapidly at first and then remains approximately the same with the decrement of strength (the improvement of toughness). Moreover, it is detected that simultaneously upgrading the strength and toughness of high‐strength steels cannot improve the FCG resistance. Finally, it is believed that the microscopic fatigue damage mechanism is the major factor determining the FCG resistance rather than the macroscopic strength–toughness combination, and the factors affecting the FCG resistance of AISI 4340 steel are mainly the pre‐existing dislocations and carbide precipitates. [ABSTRACT FROM AUTHOR]

The study aimed to investigate the effects of 'Zhang Za Gu' on the semen quality and serum biochemical indexes in male breeder rabbits. Thirty-six healthy adult Iraqi male rabbits with good sexual desire were randomly divided into six groups, with six replicates in each group and one breeder rabbits in each replicate. Rabbits in each group were fed diets containing 0, 5%, 10%, 15%, 20%, and 25% 'Zhang Za Gu', respectively. The pretrial period was seven days, and the pretrial period was 90 days. The results showed that, compared to day 30, sperm motility and sperm density of the experimental groups increased on the 60th day and the 90 th day ( P<0.05), while semen volume and sperm abnormality rate showed no significant changes ( P>0.05). Different levels of 'Zhang Za Gu' had no significant impact on the serum biochemical indices of male breeder rabbits ( P>0.05). The study indicates that considering factors such as feed cost and semen quality, the optimal effect is observed when 'Zhang Za Gu' appending proportion is 10%. [ABSTRACT FROM AUTHOR]

Nerves play important roles in organ development and tissue homeostasis. Stem/progenitor cells differentiate into different cell lineages responsible for building the craniofacial organs. The mechanism by which nerves regulate stem/progenitor cell behavior in organ morphogenesis has not yet been comprehensively explored. Here, we use tooth root development in mouse as a model to investigate how sensory nerves regulate organogenesis. We show that sensory nerve fibers are enriched in the dental papilla at the initiation of tooth root development. Through single cell RNAsequencing analysis of the trigeminal ganglion and developing molar, we reveal several signaling pathways that connect the sensory nerve with the developing molar, of which FGF signaling appears to be one of the important regulators. Fgfr2 is expressed in the progenitor cells during tooth root development. Loss of FGF signaling leads to shortened roots with compromised proliferation and differentiation of progenitor cells. Furthermore, Hh signaling is impaired in Gli1-CreER;Fgfr2fl/fl mice. Modulation of Hh signaling rescues the tooth root defects in these mice. Collectively, our findings elucidate the nerve-progenitor crosstalk and reveal the molecular mechanism of the FGF-SHH signaling cascade during tooth root morphogenesis. [ABSTRACT FROM AUTHOR]

It is rather difficult to observe, record and analyze the pore-collapse-induced initiation of a 1,3,5,7-tetranitro-1,3,5,7-tetrazocane or HMX crystal via experiment because it is an extreme phenomenon involving multiphysics (such as shock, phase change of HMX) and chemical reactions (thermal decomposition of HMX) occurring in microseconds or even nanoseconds. Herein, a mechanical-thermal-chemical coupled finite element model is proposed to simulate the pore collapse in a HMX crystal under a shock loading at velocities under 500 m/s. A viscoplastic constitutive model and a Birch-Murnaghan equation of state (EoS) are employed to predict the mechanical response of the HMX crystal. The melting of the HMX crystal is also considered. A multi-step thermal-decomposition model is employed to simulate the chemical reaction of the HMX. Firstly, numerical simulations were implemented for a few plane shock experiments and it is demonstrated that the material model of HMX have reasonable accuracy. Then, the pore collapse in a HMX crystal under a shock at 500 m/s was simulated. It is shown that severe plastic deformation and high-velocity impact of HMX jet both contribute to the temperature rise of local materials. Finally, the influence of pore size on the calculated maximum temperature of the HMX crystal was simulated under various shock velocities ranging from 100 m/s to 500 m/s. It seems that there exists an "optimal" pore size for the HMX crystal to obtain the highest temperature under a shock, which is explained with simulation results. [ABSTRACT FROM AUTHOR]

Traditional rural settlements in China have long been recognised for their unique cultural and ecological values. However, rapid urbanisation and rural revitalisation processes pose significant threats to the sustainability of these traditional living environments. This study aimed to develop an innovative multi-dimensional framework based on the SciBERT algorithm in order to evaluate the residential environment of traditional settlements in Northern Jiangxi, China. Drawing on theories from landscape ecology, cultural geography and sustainable development, the framework encompasses four key dimensions: ecological suitability, cultural continuity, liveability and sustainability. A set of quantitative and qualitative indicators was constructed under each dimension based on a comprehensive literature review. The analytic hierarchy process (AHP) was then employed to determine the relative weights of these indicators. Data were collected from interviews with 13 respondents and an analysis of 68 Science Citation Index Expanded (SCIE) articles. The proposed framework was applied to assess the residential environment of three representative traditional settlements in Northern Jiangxi. The results revealed the strengths and weaknesses of each settlement, providing valuable insights for targeted conservation and revitalisation strategies. This study contributes to urban planning research by offering a holistic and empirically validated approach to evaluating the multi-faceted residential environment of traditional settlements, which can inform both academic research and practical policymaking in the context of rural development. [ABSTRACT FROM AUTHOR]

Objective:To observe the curative effects of acupuncture combined with kinesitherapy for the treatment of sleep disorder in senile stroke patients.Methods:80 sleep disorder in senile stroke patients were randomly assigned to treatment group (n=40) and control group (n=40). The treatment group was treated with acupuncture and kinesitherapy, and the control group received estazolam tablets for four weeks. The pittsburgh sleep quality index (PSQI), self-rating scale of sleep (SRSS), TCM symptom scale, barthel index (BI) and quality of life (QOL) were examined before and after treatment.Results:The difference-value of PSQI, SRSS, TCM symptom scale, BI and QOL in the treatment group before and after treatment was higher respectively than those in the control groups, and the differences were significant (P