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Microbial infection as a type of environmental risk factors is considered to be associated with long-term increased risk of dementia, including Alzheimer’s disease (AD). AD is characterized by two neuropathologically molecular hallmarks of hyperphosphorylated tau and amyloid-β (Aβ), the latter generated by several biochemically reactive enzymes, including γ-secretase. However, how infectious risk factors contribute to pathological development of the AD core molecules remains to be addressed. In this work, we utilized a modified herpes simplex virus type 1 (mHSV-1) and found that its hippocampal infection locally promotes Aβ pathology in 5 × FAD mice, the commonly used amyloid model. Mechanistically, we identified HSV-1 membrane glycoprotein US7 (Envelope gI) that interacts with and modulates γ-secretase and consequently facilitates Aβ production. Furthermore, we presented evidence that adenovirus-associated virus-mediated locally hippocampal overexpression of the US7 aggravates Aβ pathology in 5 × FAD mice. Collectively, these findings identify a herpesviral factor regulating γ-secretase in the development and progression of AD and represent a causal molecular link between infectious pathogens and neurodegeneration.

Cell morphology and motility are crucial trait of somatic cell phenotype, closely linked to cellular function and susceptibility to external stimuli. Oxidative damage impacts cell functionality, ultimately influencing cell morphology and motility. In this study, the changes in cell state were characterized and quantified through dynamic analysis of cell morphodynamic parameters, thereby reflecting the impairment of cellular function. The protective effects of antioxidants on oxygen-damaged cells were assessed in terms of cellular morphology and motility, based on the aforementioned findings.

Purpose: The purpose of this paper is to compare the thermal resistances between optimized gallium- and water-based heat sinks to show which one is superior. Design/methodology/approach: Taking the thermal resistances of heat sinks as the goal function, an optimization process is programmed based on the genetic algorithm. The optimal channel/fin widths and the corresponding thermal resistances of gallium- and water-based heat sinks are obtained and compared with/without a laminar flow constraint. The analytic model and CFD method are applied in different situations to ensure sufficient accuracy. Findings: The results show that in the laminar regime, the thermal resistance of optimized gallium-based heat sink is lower than the water-based counterpart in most cases, but the latter becomes better if it is long enough or the channel is sufficient high. Without the laminar constraint, the thermal resistance of the optimized gallium-based heat sink can be decreased by 33-45 per cent compared with the water-based counterparts. It is interesting to find that when the heat sink is long or the channel height is short, the optimal geometry of gallium-based heat sink is a mini gap. Originality/value: This paper demonstrates that the cooling performance of gallium-based heat sink can be significantly improved by optimization without the laminar flow constraint. [ABSTRACT FROM AUTHOR]

The main objective of this study is to investigate the effect of cementitious capillary crystalline waterproofing (CCCW) material on the water impermeability and microstructure of concrete. The water impermeability of concrete covered with or without CCCW material was tested according to the Chinese standard GB 18445-2012. The results indicate that concretes coated with CCCW material showed much higher water impermeability than blank ones, and the ratio of water impermeability pressure between them reached 275. The samples obtained in various depths of hardened cement paste specimens with or without CCCW coating were analyzed through scanning electron microscopy (SEM) and thermogravimetry-differential scanning calorimetry (TG-DSC), to study the differences in microstructure and hydration products. The results present that after a 28-day standard curing, there were lots of ettringite crystals and CaCO3 formed in the paste in 1 cm from the coating, but the action depth of the CCCW coating could not reach 3 cm. The ettringite and CaCO3 is precipitated in the pore structure of cement matrix and filling the voids, which leads to the significant enhancement in water impermeability.

ABSTRACTIntestinal dysbiosis frequently occurs in abdominal radiotherapy and contributes to irradiation (IR)-induced intestinal damage and inflammation. Akkermansia muciniphila(A. muciniphila) is a recently characterized probiotic, which is critical for maintaining the dynamics of the intestinal mucus layer and preserving intestinal microbiota homeostasis. However, the role of A. muciniphilain the alleviation of radiation enteritis remains unknown. In this study, we reported that the abundance of A. muciniphilawas markedly reduced in the intestines of mice exposed to abdominal IR and in the feces of patients who received abdominal radiotherapy. Abundance of A. muciniphilain feces of radiotherapy patients was negatively correlated with the duration of diarrhea in patients. Administration of A. muciniphilasubstantially mitigated IR-induced intestinal damage and prevented mouse death. Analyzing the metabolic products of A. muciniphilarevealed that propionic acid, a short-chain fatty acid secreted by the microbe, mediated the radioprotective effect. We further demonstrated that propionic acid bound to G-protein coupled receptor 43 (GRP43) on the surface of intestinal epithelia and increased histone acetylation and hence enhanced the expression of tight junction proteins occludin and ZO-1 and elevated the level of mucins, leading to enhanced integrity of intestinal epithelial barrier and reduced radiation-induced intestinal damage. Metformin, a first-line agent for the treatment of type II diabetes, promoted intestinal epithelial barrier integrity and reduced radiation intestinal damage through increasing the abundance of A. muciniphila. Together, our results demonstrated that A. muciniphilaplays a critical role in the reduction of abdominal IR-induced intestinal damage. Application of probiotics or their regulators, such as metformin, could be an effective treatment for the protection of radiation exposure-damaged intestine.

For patients with chronic kidney disease (CKD), adequate protein intake is required to cope with proteinuria-induced protein loss, but excessive protein consumption may increase renal pressure and exacerbate kidney injury. In contrast to macromolecular proteins, peptides with high tissue permeability and biological activity can efficiently serve as protein sources without exerting glomerular pressure. To investigate the potential of peptides as nutritional intervention in CKD, we initially optimized CKD mouse model by treating with 75 mg/kg/day adenine for up to 21 days. Subsequently, we confirmed that peptides exhibited higher increase in survival rate of CKD mice compared to proteins, possibly due to their relatively high oligopeptide levels of 64.5%. Additionally, compared to positive control group, the soy peptides replacement feed significantly reduced serum urea nitrogen levels (15.4%, P < 0.05) and notably decreased the cross-sectional area of renal tubules (13.1%, P < 0.05) as observed through HE staining. The findings further indicated that soy peptides ameliorated kidney damage by inhibiting inflammatory factors TNF-α and IL-6 expression. Combined with peptides composition analysis, soy peptides were shown to aid in regulating the acid-base balance in mice with CKD. In summary, this study evidenced that soy peptides are viable protein source for nutritional intervention to ameliorate the progression of CKD.

Background: Systemic lupus erythematosus–associated immune thrombocytopenia (SLE-ITP) is characterized by relapse. The risk factors of relapse and appropriate maintenance therapy strategy deserve further exploration.Objectives: To determine the risk factors for relapse and appropriate maintenance therapy in significant SLE-ITP patients (a platelet count ⩽30 × 109/l) after the first complete response.Design: Retrospective cohort study using the medical records of 105 patients diagnosed as significant SLE-ITP in Fujian Medical University Union Hospital during December 2012 to March 2021. Patients were followed through a call for observations in January 2022.Methods: Data including demographics, initial clinical feature, induction and maintenance therapy, and outcome at the end of follow-up were analyzed. Risk factors for significant relapse were analyzed using multivariate logistic regression models. The cumulative hazard of significant relapse and the duration of response were estimated, and the differences in outcome between groups were compared using the Cox regression analysis.Results: A total of 65 significant SLE-ITP patients were eligible for the final analysis. Median [interquartile range (IQR)] follow-up duration and median [IQR] duration of response were 62.2 [41.0–79.6] months and 43.4 [20.3–68.7] months, respectively. After the first complete response, 19/65 (29.2%) had a significant relapse. Compared with sustained clinical remission (SCR) + sustained response (SR) group, significant relapse group had a higher proportion of discontinued patients (47.4% versus8.7%, p= 0.001). Among the 13 discontinued patients, the duration of maintenance therapy of the patients in significant relapse group was significantly shorter than that of the patients in SCR + SR group (months, median [IQR], 43.1 [32.0–62.4] versus12.0 [5.1–22.0], p= 0.009). Multivariate logistic regression analysis showed that drug withdrawal was an independent risk factor for significant relapse [odds ratio (OR) = 10.4, confidence interval (CI) 95% 2.2–47.8, p= 0.003]. There was no significant difference between glucocorticoids (GCs) + hydroxychloroquine (HCQ) group and GCs + HCQ + immunosuppressive agents (ISAs) group in significant relapse rate (26.7% versus22.2%, p> 0.05). The two SR curves of GCs + HCQ and GCs + HCQ+ ISA group basically coincided by the Cox regression analysis, demonstrating comparable long-term outcomes (p> 0.05).Conclusion: Drug withdrawal, especially abrupt withdrawal with insufficient duration of maintenance therapy, is an independent risk factor for significant relapse of SLE-ITP. HCQ combined with GCs is expected to be the first choice of the maintenance therapy for SLE-ITP patients.

Sterling alloy is widely used in the jewelry industry. Its anti-tarnish property is one of its most important characteristics. In this study, the effect of tin on the corrosion resistance, and tarnish resistance properties of sterling silver alloy were investigated quantized. The difference between anti-corrosion and anti-tarnish properties was investigated in this paper. The tarnish and corrosion resistance of sterling silver improved as tin content increased. However, there was a point at which increasing tin content further led to poor anti-tarnish properties, even though the alloy retained considerable anti-corrosive properties.

Effect of antioxidants in oxidative stress-induced cell damage has been extensively studied, but its effects on cell macroscopic phenomena have rarely been explored. Cell morphology and motility are two interrelated cellular processes reflecting cellular function phenotype, and the real-time imaging technology is key for the study of these processes. In this study, we used two known antioxidants, pyrroloquinoline quinone (PQQ) and rutin, to explore the antioxidant effects on cell morphology and motility in rotenone-damaged NIH3T3 cells, as well as roles in their antioxidant function based on Cytation 7 Cell Imaging Multi-Mode Reader. First, NIH-3T3 cells were pretreated with PQQ and rutin for 4 h and then rotenone was used to induce oxidative damage. It was found that PQQ (2 μM) and rutin (300 μM) had similar protective effects on the proliferation activity of rotenone-damaged cells. Subsequently, the morphology and motility of the treated cells were quantified. Results showed that both PQQ and rutin could significantly inhibit morphological changes including cell shape index and cell surface of the damaged cells, however PQQ had a stronger effect on cell motility under the specific experimental concentrations. Using principal component analysis (PCA), we further demonstrated that the quantified cell morphology and motility were consistent with the cell proliferation activity. Consequently, quantification of cell morphology and motility as evaluation indices may serve as potential reference values for the evaluation of biological activity of antioxidants.

This method provides a green and efficient method to selectively synthesize dihydroquinazolinones and quinazolinones catalyzed by Y(OTf)3. The usage of molecular oxygen in air renders this protocol very attractive and practical.

This method provides a practical, effective and green synthetic approach to benzothiazoles which are important units in many biologically active compounds.

A recyclable and efficient Yb/NaY zeolite catalyst was obtained for catalyzing the condensation synthesis of quinoxaline. The catalyst gave desired products in good to excellent yields (up to 94%), and could be reused several times without any loss of its catalytic activity.

A class of problems is usually met in actual engineering, i.e., the low-speed motion of the slider of a linkage in a section of its stroke is required based on the prerequisite of ensuring the slider’s definitive working times. Through analyzing the mechanisms of low-speed Stephenson’s six-bar linkage, the main parameters of the slider’s low motion are found. The Stephenson’s six-bar linkage satisfying low-speed working requirements is designed through a mechanical press as an example.

The environmental pollution of the rural area partly results from the excrement of sheep, cattle and poultry. In a systematic project of regulating and harnessing the excrement, the additive is applied to mix the faeces to remove the unbearable smell from livestock excreta and to make better and comprehensive utilization of the excreta. At present, the mixers at home and abroad are not applicable to mix the excrement of domestic animals for the reason that there are so many fibers in it. The shapes of sheep and cattle excrement like a ball which demands the rotor of the mixer to have the clipping function. Thus, the clipping and mixing machine is designed. Its principle, structure, technique and its main parameters are analyzed and proved in this paper.

Wheat lodging results in great losses of wheat production about 10%~30% every year. It is very important to study the lodging and to find new way to improve the quality of wheat stalks and its anti-lodging characteristics. The study about the changing of wheat stem mechanical properties with the elastic modulus and stem structure is carried on the basement of theoretical model, experimental improvement, and finite element method. Results show that the stem is more difficult to lodge if the ratio is bigger, which can be calculated through elastic modulus multiplying wall thickness and divided by diameter.

A method to estimate the thermodynamic properties of Multi- component white gold alloys from those of constitutive binary alloys was proposed. The Miedema's theory and Chou model. were used to calculate the formation enthalpies of Au–Cu–Ag-Zn-RE alloys. The agreement between the calculation and experiment is reasonable. Formation enthalpies of Au–Cu–Ni-Zn-RE and relative stability of their intermetallic compounds were predicted with present method.

In order to enhance the thermal efficiency of heating and dring facilities, the energy-saving high infrared radiation materials were synthesized by the solid state method for 2h at 950, 1050 and 1150 ℃, respectively, and rapid cooling in the air, from transitional metal oxides Fe2O3, Cr2O3, MnO2 andCuO. The strcture and emission property of the samples were characterized through X-ray diffractomete, scanning electron microscop and infrared radiation meter. The results show that the main phases of resultants are spinel ferrites, and with increasing temperature, crystals become better and multiple spinel and like-spinel structures are formed. The infrared radiance represents a nonlinear variation with calcining temperature. The coatings on the stainless steel surface prepared with the materials with self-made binders have good infrared radiation, up to a maximum of 0.90, and have perfect resistance to thermal shock and may arrive at 25 times (RT←→800 ℃), exhibiting fairly high binding strength. So the materials which are apply to on the internal wall of heating and drying facilities are believed to result in an long-term energy conservation.

Superfine Ag2WO4 antibacterial powders, which are prepared by supersonic assisted homogeneous precipitation method, is added 1.0-1.5wt.% to sanitary ceramics, having 90% antimicrobial action, and achieve good bactericidal effects. The antibacterial ceramics with Ag2WO4 were soaked into acid and alkali for 3 months, and antibacterial activities had little change, keeping good antimicrobial durability. Finally, the antibacterial mechanism of Ag2WO4 ceramics is advanced.

In this paper, Au-Zn-Cu-Ni alloy series was take as a benchmark. Nickel element was replaced by Manganese in different ratios. The existing state and distribution law of Manganese, and the effects of the Manganese on microstructure and properties of gold alloys were studied. The mechanism of effects of Manganese on the colour and the release of nickel of gold alloys were discussed.

The objective of this research was to investigate the effect of Cobalt in as-cast sterling silver alloys used in jewellery industry on microstructure, mechanical properties, and tarnish resistance. The tarnish and corrosion resistance of sterling silver were improved with cobalt. This may be due to the grain refinement and the forming of cobalt oxide film on the surface of sliver alloy.

Carbon fibre reinforced carbon and silicon carbide dual matrix composites (C/C-SiC) are new type of high performance brake materials, and possess a series of outstanding advantages. In the present study, the C/C-SiC brake composites were fabricated by the combination of chemical vapor infiltration with liquid silicon infiltration. The fabric preforms were prepared by three dimension needling method. Results show the SiC form inside the short-cut fabric, around the needing fibre and among the fibre bundles in the non-woven web of the C/C-SiC composites. The average static friction coefficient of the C/C-SiC materials was 0.61. The average dynamic friction coefficient were between 0.41 and 0.54 with the increase of brake speed, and the wear rates are not sensitive to the brake speed and maintained about 0.02 cm3•MJ-1 all along.

Carbon fibre reinforced carbon and silicon carbide dual matrix composites (C/C-SiC) were fabricated by warm compacted in-situ reaction. The C/C-SiC composites microstructure and tribological properties at different brake speeds were investigated. The results indicated that the composites were composed of 58 wt% C, 37 wt% SiC and 5 wt% Si. The density and open porosity were 2.0 g•cm-3 and 10%, respectively. The C/C-SiC brake composites show excellent tribological performance, including a good stability of brake, the coefficient of friction between 0.57 and 0.67, and the wear rate less than 2.02 cm3•MJ-1. These results show that the C/C-SiC brake composites are the promising candidates for advanced brake and clutch systems.

A method to estimate the thermodynamic properties of Multi- component white gold alloys from those of constitutive binary alloys was proposed. The Miedema's theory and Chou model. were used to calculate the formation enthalpies of Au–Cu–Ni-Zn-RE alloys. The agreement between the calculation and experiment is reasonable. Formation enthalpies of Au–Cu–Ni-Zn-RE and relative stability of their intermetallic compounds were predicted with present method.

In this paper, A kind of ideal non-cyanide silver deposits was obtained by joining the ultrasonic. ultrasonic frequency of 28KHz, power increased from 0-500W, XRD tests show:with the increasing in electric power deposition, silver coating (111) and (200) crystal plane orientation significantly improved, and (220) crystal plane orientation declined . With the ultrasonic power increased, silver deposition current efficiency increased first and then reduced. the grain size refined with the ultrasonic increasing .the corrosion resistance decreased with the ultrasonic increasing.and SEM showed that the grain sizes decreased with the ultrasonic.

AbstractPolydnavirus was purified from the calyx fluid of Cotesia plutellaeovary. The genomic features of C. plutellaepolydnavirus (CpPDV) were investigated. The viral genome consists of at least 12 different segments and the aggregate genome size is a lower estimate of 80kbp. By partial digestion of CpPDV DNA with BamHI and subsequent ligation with BamHI‐cut plasmid Bluescript, a representative library of CpPDV genome was obtained.

The oxidation tests of five different porosity C/C composites for non-isothermal oxidation and three different porosity samples for isothermal oxidation in O 2 and two samples which had approximate porosity and different total surface area values for static air oxidation were performed. Results show that the oxidation was controlled by the total surface area other than by the open porosity or the densification degree of samples or amount of pore entrance. The oxidation occurred preferentially at the fiber-matrix interface and pyrocarbon-pyrocarbon interface, and then progressed along the micro-cracks between the interfaces.

Abstract: In this paper a two-dimensional (2-D) model of earthquake fault rupturing was presented. It was estabilished on the basis of 1-D spring-block model. Using this model, we studied the dynamical plane-strain fracture problem, modeled the whole dynamical process of nucleating, expanding and propagating of fracture on a 2-D fault with homogeneous or inhomogeneous rupture strength distribution. Our studies show that under homogeneous prestress condition, the fault will gain enough momentum to tear strong obstacles in their propagating path. The rupturing fronts can also propagate forth around the isolated barriers. It is shown that the stopping conditions for rupturing processes play an important role in modeling whole earthquake process. We also studied the dynamical rupturing problems of the fault on which the rupture strength distribution is inhomogeneous, and modeled the earthquake sequence generated on a 2-D fault with the strength distribution of fractal structure. It possesses some similar features as a seismic sequence in the nature. These features mainly depend on the distribution of rupture strength on the fault plane and the level of initial stress drop. The modeling studies which were established on the basis of experiments and observations provided the physical basis for explaining some statistical rules of seismicity.

Abstract: According to the source mechanism of the main shock and the distribution feature of the aftershocks occurring in the southern Taiwan Straits on Sept. 16, 1994, in this paper the authors analysed the source rupture feature of the major earthquake, demonstrated that this seismic sequence possessed the characteristics of a large intraplate earthquake. And according to the seismotectonic background and the historical seismicity in the area, the authors clarified the active characteristics of the seismically active belts along northwestern direction and analysed preliminarily the earthquake circumstance in the southeastern coast of China.