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In order to understand the pyrolysis and explosion characteristics of typical wood fiber dusts, the pyrolysis process, kinetic parameters, and pyrolysis gas types of the two dusts were calculated and analyzed using thermogravimetric-infrared coupler with redwood fiber dust and poplar fiber dust as the research objects. The results showed that the pyrolysis rate of mahogany dust was higher than that of poplar dust, and the activation energy was lower. The thermal weight loss of the two dusts was mainly reflected in the thermal decomposition at low temperature and combustion reaction at high temperature, and the pyrolysis products were mainly CO2, CO, H2O and a small amount of alkanes, alcohols, aldehydes, ketones and carboxylic acids, and the combustion products were mainly CO2 and CO, and the amount of CO2 of combustion products of mahogany fiber was higher than that of poplar fiber, while the pyrolytic combustion process of poplar fiber is relatively complex, with a high degree of incomplete combustion. The dust cloud minimum ignition temperature and maximum explosion pressure of the two wood fiber dusts were tested. Redwood fiber dust was more dangerous than poplar, and the mechanism was explained from the thermogravimetric-infrared test results. The results of this study could provide some data reference for the development of relevant policies and measures at sites involving such dusts. [ABSTRACT FROM AUTHOR]

Neuron is the basic unit of nervous system. Studying the fine morphology of neurons is crucial for understanding the structure of neural network and the manner of neural information processing. At present, effective methods to visualize fine morphology of neurons with specific cell types and specific projection are still lacking. In this paper, a recombination vesicular stomatitis virus (VSV) was designed, with nucleoprotein gene mutated and glycoprotein gene deleted. The virus, VSV-△G-NR7A-EGFP, was capable of highlighted morphology of the labelled neurons in a short time. With specific transgenic animals and a helper virus rAAV-EF1α-Dio-Bfp-Tva, it was demonstrated that, a further constructed virus VSV-△G-EnvA-NR7A-EGFP could sparsely and specifically label D2R neurons with nucleus accumbens-lateral hypothalamus (NAc-LH) projection and dopamine neurons with ventral tegmental area (VTA)-NAc projection.

Quantitative analyses of molecular expression, cell counts and neural network connections among different brain regions are essential in brain science research. Based on Paxinos and Franklin's the Mouse Brain in Stereotaxic Coordinates (Ⅱ) and public image processing software such as Photoshop and ImageJ, we developed a convenient method for semi-automatic segmentation and cell counting on brain sections. A standard template for brain region segmentation was first obtained from the Paxinos and Franklin's mouse brain atlas. Photoshop was then used to transform the standard template semi-automatically into the space of brain sections, yielding masks of segmented brain regions. Finally, ImageJ was used to analyze the data in different brain regions. This method is useful for immunohistochemical and neuron distribution pattern analyses, as well as neural network labelling studies. The method does not require expensive commercial image analysis software, and is also easy to implement and use.

The high strength and stiffness-to-weight ratios of structural steel often result in relatively slender members and systems, which are governed to a great extent by stability limit states. However, predicting the stability of slender structures is difficult due to various inherent uncertainties in material and geometry. Generally, structural and member stabilities are nonlinear problems that cannot be directly evaluated based on the section strength using conventional analysis method. Nonlinear behaviors are basically categorized as materially and geometrically nonlinear, which can be observed at the cross-sectional, member, and frame levels. To provide a comprehensive understanding of the current state-of-the-art non-linear behavior and design of steel structures and to identify key areas for future research and development, this paper presents a review on the materially and geometrically nonlinear effects of steel structures. A discussion of the effects of material yielding accentuated by the presence of residual stresses, initial imperfections, and end conditions will be conducted. The stiffness reduction due to second-order effects and material yielding will be illustrated. Moreover, current and emerging design approaches that consider nonlinear responses will also be reviewed and evaluated. Lastly, with the development of modern flexible and complex steel structures, which sometimes violate fundamental assumptions of the current stability design method, the application of advanced analysis and design methods will be explored. [ABSTRACT FROM AUTHOR]

Domestic biodegradable wastes (DBW) pose a threat to environmental quality and human health. Bioconversion via black soldier fly larvae (BSFL; Hermitia illucens L.) is an expedient way for converting 'waste to resource' (insect protein and biofertilizer). Although researches abounded in laboratory-reared experiments and bioconversion mechanisms were pertinent, the void of data from actual and full-scale operation restricts the intensification of BSFL technology and its global adoption. Hence, a full-scale BSFL bioconversion system lasting 4 years in Hangzhou (China) was investigated, and the feasibility and efficiency of 15 tonnes of DBW per day were studied. Through continuous technical optimization, the average production of fresh larvae was increased from 8.5% in 2017 to 15.3% in 2020, along with bioconversion rate of final vermicompost decreased from 35.4% to 14.5%. The total biomass reduction rate in 2020 was 68.7 ± 17.4 kg/(m3 d), equivalent to 0.735 ± 0.215 kg/(kg d) in the form of fresh larvae. Crude fat in fresh larvae accounted for 13.4%, and crude protein accounted for 16.2% in which the determined amino acid profile bore a strong resemblance to fish meal only except histidine and tyrosine. Its economic benefits proved the feasibility of this technology, and the profit reached up to 35.9 US$ per tonne of DBW in 2019. In conclusion, BSFL bioconversion system under current 'insect-farm' operation was a promising solution for DBW treatment with value-added waste recycling. [ABSTRACT FROM AUTHOR]

Background: Molecular targeted therapy for non-small cell lung carcinoma (NSCLC) is restricted due to resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). This study evaluated the effects of dual targeting of MEK and PI3K in human EGFR-TKI resistant NSCLC cell lines.Methods: EGFR-TKI resistant NSCLC cell lines H1975, H460, and A549, with different mutation and amplification status in EGFR, K-RAS, PIK3CA, and MET genes, were treated with a MEK162 (MEK inhibitor) and BKM120 (PI3K inhibitor) combination or a BIBW2992 (EGFR inhibitor) and ARQ197 (MET inhibitor) combination and assayed for cell proliferation, apoptosis, and cell cycle distribution.Results: Dual targeting of MEK and PI3K efficiently inhibited the cell proliferation, induced apoptosis and the G0/G1 cell cycle, and decreased the phosphorylation of ERK1/2, AKT, S6, and 4E-BP1. H460 cells with K-RAS and PIK3CA mutation were most sensitive to MEK162 and BKM120 combinations. H1975 cells with EGFR and PIK3CA mutation and MET amplification were sensitive to BIBW2992 and ARQ197 combinations.Conclusion: Dual targeting regulated the proliferation of EGFR-TKI-resistant NSCLC cells, especially mutants in K-RAS and PIK3CA that are promising for EGFR-TKI-resistant NSCLC therapeutics. [ABSTRACT FROM AUTHOR]

Background/Aims Diabetic nephropathy (DN) is one of the main causes of end-stage kidney disease worldwide. Emerging studies have suggested that its pathogenesis is distinct from nondiabetic renal diseases in many aspects. However, it still lacks a comprehensive understanding of the unique molecular mechanism of DN. Methods A total of 255 Affymetrix U133 microarray datasets (Affymetrix, Santa Calra, CA, USA) of human glomerular and tubulointerstitial tissues were collected. The 22 215 Affymetrix identifiers shared by the Human Genome U133 Plus 2.0 and U133A Array were extracted to facilitate dataset pooling. Next, a linear model was constructed and the empirical Bayes method was used to select the differentially expressed genes (DEGs) of each kidney disease. Based on these DEG sets, the unique DEGs of DN were identified and further analyzed using gene ontology and pathway enrichment analysis. Finally, the protein–protein interaction networks (PINs) were constructed and hub genes were selected to further refine the results. Results A total of 129 and 1251 unique DEGs were identified in the diabetic glomerulus (upregulated n  = 83 and downregulated n  = 203) and the diabetic tubulointerstitium (upregulated n  = 399 and downregulated n  = 874), respectively. Enrichment analysis revealed that the DEGs in the diabetic glomerulus were significantly associated with the extracellular matrix, cell growth, regulation of blood coagulation, cholesterol homeostasis, intrinsic apoptotic signaling pathway and renal filtration cell differentiation. In the diabetic tubulointerstitium, the significantly enriched biological processes and pathways included metabolism, the advanced glycation end products–receptor for advanced glycation end products signaling pathway in diabetic complications, the epidermal growth factor receptor (EGFR) signaling pathway, the FoxO signaling pathway, autophagy and ferroptosis. By constructing PINs, several nodes, such as AGR2, CSNK2A1, EGFR and HSPD1, were identified as hub genes, which might play key roles in regulating the development of DN. Conclusions Our study not only reveals the unique molecular mechanism of DN but also provides a valuable resource for biomarker and therapeutic target discovery. Some of our findings are promising and should be explored in future work. [ABSTRACT FROM AUTHOR]

The practices of head and neck surgical oncologists must evolve to meet the unprecedented needs placed on our health care system by the Coronavirus disease 2019 (COVID‐19) pandemic. Guidelines are emerging to help guide the provision of head and neck cancer care, though in practice, it can be challenging to operationalize such recommendations. Head and neck surgeons at Wuhan University faced significant challenges in providing care for their patients. Similar challenges were faced by the University of Toronto during the severe acute respiratory syndrome (SARS) pandemic in 2003. Herein, we outline our combined experience and key practical considerations for maintaining an oncology service in the midst of a pandemic. [ABSTRACT FROM AUTHOR]

The housefly larvae (Musca domestica) vermireactor is capable of highly efficient waste reduction for swine manure management; however, effectiveness of larvae-vermicompost land utilization and the associated impact on soil environment are poorly understood. This study, which integrated incubation pot experiments and field plot tests on a chrysanthemum (Chrysanthemum morifolium) farm, was designed to investigate soil biochemical and microbial functions in response to inorganic fertilizer (NPK), vermicompost (VC) application, and/or combination of inorganic fertilizer and vermicompost (I + V). Pot experiments indicated that available soil nitrogen (N), phosphorus (P), and potassium (K) were significantly higher (21%-43%, 206%-306%, and 35%-36%, respectively) with VC treatment compared to NPK treatment; meanwhile, soil organic carbon (C), N and P mineralization was increased by 46%-57%, 53%-70%, and 30%-113%, respectively. Vermicompost application increased soil highly labile organic C by 19% to 42%. Vermicompost also enhanced soil enzymatic activities: 37%-68% for dehydrogenase, 22%-107% for urease, and 3.4%-56% for phosphatases, but activities of soil β-1,4-glucosidase and β-1,4-N-acetylglucosaminidase were reduced by 17%-53% and 24%-42%, respectively. Compared to pot experiment, continuous land application of vermicompost overwhelmingly caused soil nutrient accumulation, increased soil C stock and microbial biomass, enhanced soil mineralization, and improved C-, N-, and P-related enzymatic activities. Co-inertia analysis indicated that soil fertility indices positively correlated with most microbiological indices. This work reveals VC as a new biofertilizer for crop production and highlights its merit on soil health improvement. [ABSTRACT FROM AUTHOR]

Summary: Vermicomposting using black soldier fly (BSF) larvae (Hermetia illucens) has gradually become a promising biotechnology for waste management, but knowledge about the larvae gut microbiome is sparse. In this study, 16S rRNA sequencing, SourceTracker, and network analysis were leveraged to decipher the influence of larvae gut microbiome on food waste (FW) biodegradation. The microbial community structure of BSF vermicompost (BC) changed greatly after larvae inoculation, with a peak colonization traceable to gut bacteria of 66.0%. The relative abundance of 11 out of 21 metabolic function groups in BC were significantly higher than that in natural composting (NC), such as carbohydrate‐active enzymes. In addition, 36.5% of the functional genes in BC were significantly higher than those in NC. The changes of metabolic functions and functional genes were significantly correlated with the microbial succession. Moreover, the bacteria that proliferated in vermicompost, including Corynebacterium, Vagococcus, and Providencia, had strong metabolic abilities. Systematic and complex interactions between the BSF gut and BC bacteria occurred over time through invasion, altered the microbial community structure, and thus evolved into a new intermediate niche favourable for FW biodegradation. The study highlights BSF gut microbiome as an engine for FW bioconversion, which is conducive to bioproducts regeneration from wastes. [ABSTRACT FROM AUTHOR]

Schiff base butyltin complexes C1 ∼ C3 have been synthesized via the reaction of dibutyltin oxide with the substituted salicylaldehyde-o-aminophenol Schiff base ligands (L1 ∼ L3), respectively. The complexes have been characterized by elemental analysis, IR, UV-Vis, 1H NMR, 13C NMR spectra and the crystal structures have been determined by X-ray diffraction. The anticancer activity of the Schiff base ligands L1 ∼ L3 and complexes C1 ∼ C3 against five species of cancer cells which are MCF7, Colo205, NCI-H460, Hela and HepG2 were tested respectively, the tests showed that C3 exhibited significant anticancer activity for the cancer cells in comparison with other complexes. The interaction between C3 and calf thymus DNA were studied by fluorescence, UV-Vis and Viscosity experiment, the results show that the interaction of C3 with calf thymus DNA was intercalation. [ABSTRACT FROM AUTHOR]

Conclusion: The auditory brainstem response (ABR) wave I threshold, latency and amplitude are insensitive to spiral ganglion neurons (SGNs) degeneration, but are sensitive to the degeneration of Schwann cells and can estimate the status of Schwann cells in a neural degeneration mouse model. The thorough pre-operative ABR assessment would be helpful in predicting cochlear implant performance. Objectives: This study aimed in finding a non-invasive electrophysiological method to evaluate the status of the auditory nerve and the Schwann cells in sensorineural hearing loss (SNHL) and auditory neuropathy (AN) ears, and providing useful information for candidates screening and outcome prediction in cochlear implantation. Methods: The frequency-specific acoustic ABR was recorded in mice. The immunohistochemical staining was performed to detect the SGNs and Schwann cells in mice cochlea. The correlations between ABR wave I metrics and SGNs, Schwann cells were investigated. Results: In SNHL and AN mice cochlea, statistically significant correlations between ABR wave I thresholds, latencies and amplitudes at 8, 16, and 32 kHz and their corresponding SGNs densities were found only in wave I amplitude at 8 kHz. While the ABR wave I metrics at all three frequencies showed strong significant correlations with their corresponding Schwann cells densities. [ABSTRACT FROM AUTHOR]

This paper presents results of an experimental study on the axial compression behavior of reinforced geopolymer concrete columns with demolished concrete lumps (DCLs). A total of 22 reinforced concrete short columns were tested under axial compression. The test variables include the type of fresh concrete (ordinary Portland cement concrete (CC) and geopolymer concrete (GC)), strength level of fresh concrete (FC) and demolished concrete, and replacement ratio of FC by DCLs. The test results were used to evaluate the effect of strength difference between fresh and demolished concrete, and replacement ratio of FC by DCLs on bearing capacity and deformation ductility of geopolymer concrete columns with DCLs. Data from these tests showed that the axial compression behaviors of short columns made of geopolymer concrete and ordinary concrete with DCLs were similar. The ultimate bearing capacity and stiffness of recycled concrete columns with DCLs decrease with an increase in replacement ratio. Nevertheless, the maximum reduction in bearing capacity of geopolymer recycled concrete columns is only 10%, when the replacement ratio of FC by DCLs is 24%. The strength difference between fresh concrete and DCLs has a significant influence on mechanical properties of recycled concrete columns, especially for geopolymer recycled concrete columns. Compared to ordinary recycled concrete columns with DCLs, geopolymer recycled concrete columns with DCLS exhibit a slight lower bearing capacity, but a higher ductility. [ABSTRACT FROM AUTHOR]

Objective: This study aimed in fully investigating the toxicities of ouabain to mouse cochlea and the related cellular environment, and providing an optimal animal model system for cell transplantation in the treatment of auditory neuropathy (AN) and sensorineural hearing loss (SNHL). Methods: Different dosages of ouabain were applied to mouse round window. The auditory brainstem responses and distortion product otoacoustic emissions were used to evaluate the cochlear function. The immunohistochemical staining and cochlea surface preparation were performed to detect the spiral ganglion neurons (SGNs), Schwann cells and hair cells. Results: Ouabain at the dosages of 0.5 mM, 1 mM and 3 mM selectively and permanently destroyed SGNs and their functions, while leaving the hair cells relatively intact. Ouabain at 3 mM resulted in the most severe SGNs loss and induced significant loss of Schwann cells started as early as 7 days and with further damages at 14 and 30 days after ouabain exposure. Conclusions: The application of ouabain to mouse round window induces damages of SGNs and Schwann cells in a dose- and time-dependent manner, this study established a reliable and accurate animal model system of AN and SNHL. [ABSTRACT FROM AUTHOR]

In order to obtain the energy consumption and efficiency data of simple lifts, energy transfer was studied under different working conditions. Comparative testing scheme of energy efficiency was established according to the actual situation. Among energy supply, effective nominal value and the nominal value of energy efficiency, the nominal value of energy efficiency was shose as the index to evaluate the simple lift energy consumption level. Three-phase power quality analyzer was adopted to test the energy efficiency of two different type simple lifts with same parameters. The measured values of energy supply, available energy, energy efficiency and active power were comparative analyzed with the theoretical values, under different working conditions. Finally, test results and analysis show that since there is an energy feedback loop during the falling process for the forced type simple lift, the overall traction type simple lift is more energy-saving. Also, the test results provide the foundation for energy consumption of simple lifts. [ABSTRACT FROM AUTHOR]

Objectives: We examined the prevalence and risk factors of migraine among the She population. The prevalence of migraine among She Chinese in Fujian province is high. Methods: This study is a cross-sectional survey. Subjects completed a questionnaire that collected demographic and clinical data related to migraine. Physical examination and clinical laboratory tests were performed. Data were analyzed by regression analysis. Results: Of the 5519 subjects enrolled, 2377 were male (43.1%) and 3142 female (56.9%). Of these, 581 (10.53%) experienced migraine annually, including 6.18% of males and 13.82% of females. Highest prevalence rate was among those aged 40-49 years (11.28%). The 141 (24.3%) subjects who had migraine with aura had higher incidence of family history of headache than those without aura (38.5% vs 19.9%, P < 0.0001). Conclusion: Female gender and insomnia are possible risk factors for migraine in the She population. [ABSTRACT FROM AUTHOR]

By using soil and water assessment tool (SWAT) model, this paper simulated the surface runoff intensity and the export loadings of sediment particulates and nutrients via non-point source hydrological pathway in Tiaoxi watershed, and integrated with the simulation results, analyzed the temporal and spatial distribution characteristics of non-point source pollution in the watershed in 2008. In the study area, the per unit area non-point source pollution was stronger in northern region than in southern region and in eastern region than in western region, and the weakest in central region. Among the land utilization types, farmland had the biggest contribution to the sediment loading. There were significantly positive correlations between the loadings of surface runoff and associated sediment particulates and the rainfall intensity. The export loadings of nutrients through surface runoff were higher in rainy season (from June to September) than in dry season (from December to next March), and there existed significant correlations between the surface runoff loadings of sediment particulates, organic nitrogen, and nitrate and the average gradient of lands. [ABSTRACT FROM AUTHOR]

Here we show that stem cell factor (SCF) signaling through its receptor, c-kit, is essential for the development of c-kit-expressing small- and medium-diameter primary sensory neurons. We used the W mouse, which is c-kit deficient and has a perinatal lethal phenotype due to a naturally occurring point mutation in the c-kit gene. In c-kit-null newborn mice, 52.5% of substance P immunoreactive and 31.4% of calcitonin gene-related peptide (CGRP) immunoreactive small- and medium-diameter sensory neurons were absent, whereas large-diameter sensory neurons were unaffected. Equivalent deficits occurred during embryogenesis. There was neither a developmental delay nor degeneration of differentiated neurons. We thus conclude that, in the absence of SCF signaling, neural crest-derived progenitors do not differentiate into c-kit-expressing visceral and somatic afferent neurons. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]