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In order to study the corrosion behavior of weathering high strength bolted steel in typical industrial atmospheric environment，samples compared with 35 VB bolts were taken from the industrial trial production of 10.9 grade weathering bolts to carry out the simulated periodic infiltration accelerated corrosion tests of typical industrial atmospheric environment for 24，48，96，168，and 216 hours.The corrosion behavior of high strength bolted steel with weathering resistance in simulated industrial atmosphere was studied by means of corrosion weight loss，XRD，SEM and electrochemical test.Results showed that the corrosion weight loss of both grade 10.9 and 35VB bolted steels increased with the prolongation of corrosion cycle，and the weight loss of grade 10.9 weathering bolted steel was significantly lower than that of grade 35VB bolted steel.With the prolongation of corrosion period，the diffraction peak strength of the corrosion products of the 10.9 grade weathering bolted steel and 35VB bolted steel increased，and the α-FeOOH phase diffraction peak was stronger in the 10.9 grade weathering bolted steel under the same corrosion period.Under the same period，compared with 35VB bolted steel，the self-corrosion potential of 10.9 grade weathering bolted steel was more positive，the self-corrosion current density was smaller，and the capacitance resistance arc was larger.The results indicated that the 10.9 grade weathering bolted steel with the addition of Cu，Cr and Ni alloy elements possessed excellent corrosion resistance in typical industrial atmospheric environment.

The present study aimed to shed light on the effects of altitudes and three cooking methods (boiling, steaming, and roasting) on the physicochemical quality, volatile profile, and sensorial characteristics of yak meat. Composite meat samples were prepared to represent each cooking method and altitude level from the longissimus thoracis et lumborum (LTL) muscle of nine yaks. The techniques employed were gas chromatography-mass spectrometry (GC–MS) and electronic nose (E-nose) along with chemometrics analysis to study the changes occurring in yak volatile profile, and TBARS measurement in lipid oxidation during cooking. Among the cooking methods, boiling and steaming exhibited higher protein and fat content while lower volatile compound contents. Additionally, roasted yak meat received the highest sensory scores, along with decreased L*-values, while elevated a*- and b*-values, and tenderness. A total of 138 volatile compounds were detected, and among them, 36 odorants were identified as odor-active compounds in cooked yak meat. It is evidenced that low-altitude yak presented more complex and richer flavor profiles than high-altitude ones. Moreover, yak meat from low- and high-altitude was classified into two groups by an electronic nose (E-nose) owing to distinct flavor characteristics. Overall, roasted yak meat originating from low altitudes tends to be more popular from a sensory perspective.

A series of three-dimensional porous lead dioxide anode materials were prepared by anodizing method using oxygen bubbles as templates. The effects of additives sodium acetate, cetyltrimethyl ammonium bromide(CTAB), sodium dodecyl benzene sulfonate(SDBS) and polyethylene glycol(PEG) on three-dimensional porous PbO2 anode materials were studied. The morphology and phase composition of the electrode surface were characterized by SEM and XRD. The electrocatalytic activity of the electrode material in Na2SO4 solution was determined by anodic polarization curve(LSV), cyclic voltammetry curve(CV) and AC impedance spectrum(EIS).The results show that after the addition of additives, the directional arrangement on the surface of the plating bath can promote the uniform dispersion of Pb2+, when PbO2 is deposited, the surface is coated, the particle aggregation is reduced, and the coating is flatter and denser; at the same time, due to the adsorption of organic additives, the preferred orientation of grains is changed, but the crystal form is not changed, the prepared electrode materials are still β-PbO2 with complete morphology and three-dimensional porous structure. With the addition of organic additives, the pore density of the electrode material is increased, the specific surface area of the electrode material is promoted, the charge transfer resistance in the electrocatalysis process is reduced, and the electrocatalytic activity of the electrode material is improved. Among all organic additives, the porous PbO2 electrodes added with SDBS has the largest j0 (5.514×10-5 A·cm-2) and the smallest Rct (0.3395 Ω·cm2), showing good electrocatalytic performance. According to the CV data, the qi* of the PbO2 electrode with SDBS is 0.652 C·cm-2, which is 4 times higher than that of the porous PbO2 electrode without additive, The addition of organic additives effectively increases the electrochemically active surface area of the electrode material.

Abstract Aims/Introduction Emerging evidence has suggested the detrimental role of oxidative stress in aggravating ischemia and reperfusion (IR) injury in diabetic livers. Interplay between oxidative stress and mitophagy has been shown. However, the role and mechanism of mitophagy in regulating oxidative stress and IR injury in diabetic livers remain unclear. Materials and Methods Wild‐type and db/db (DB) mice were subjected to a partial warm liver IR model. Liver injury, oxidative stress, mitophagy and related molecular pathways were analyzed. Results Here, we found that increased liver IR injury was observed in DB mice, as evidenced by higher levels of serum alanine aminotransferase and serum aspartate, worsened liver architecture damage and more hepatocellular death. DB mice also showed increased mitochondrial oxidative stress. Mitochondrial reactive oxygen species scavenge alleviated liver IR injury in DB mice. Mechanistic analysis showed that 5′ adenosine monophosphate‐activated protein kinase‐mediated mitophagy was suppressed in DB mice post‐IR. Pharmacological activation of 5′ adenosine monophosphate‐activated protein kinase by its agonist effectively restored mitophagy activation, leading to decreased mitochondrial oxidative stress and attenuated liver IR injury in DB mice. Conclusions Our findings showed that diabetes increased oxidative stress to exacerbate liver IR injury by impairing 5′ adenosine monophosphate‐activated protein kinase‐mediated mitophagy. Strategies targeting oxidative stress and mitophagy might provide a promising approach to ameliorate liver IR injury in diabetes patients.

Lipase-catalyzed stereoselective resolution of cis-(±)-dimethyl 1-acetylpiperidine-2,3-dicarboxylate (cis-(±)-1) is an attractive route for the synthesis of (S,S)-2,8-diazobicyclo[4.3.0]nonane, an important chiral intermediate of the fluoroquinolone antibiotic, moxifloxacin. In our previous study, a lipase from Sporisorium reilianum (SRL) was identified to possess excellent thermostability and pH stability. However, the low enzymatic activity of the SRL is a challenge that must be addressed. A rational design was initially employed for SRL tailoring according to the engineered Candida antarctica lipase B (CALB), resulting in a beneficial variant called SRL-I194N/V195L. Subsequently, two key amino acid residues in loop 6, L145 and L154, which might modulate the lid conformation between open and closed, were identified. A tetra-site variant, SRL-I194N/V195L/L145V/L154G (V13), with a significantly enhanced activity of 87.8 U∙mg−1 was obtained; this value was 2195-fold higher than that of wild-type SRL. Variant V13 was used to prepare optically pure (2S,3R)-dimethyl 1-acetylpiperidine-2,3-dicarboxylate ((2S,3R)-1), resolving 1 mol∙L−1 cis-(±)-1 with a conversion of 49.9% in 2 h and absolute stereoselectivity (E > 200). Excellent stability with a half-life of 92.5 h was also observed at 50 °C. Overall, the study findings reveal a lipase with high activity toward cis-(±)-1 at an industrial level and may offer a general strategy for enhancing the enzyme activity of other lipases and other classes of enzymes with a lid moiety.

Acrylic powder coating has excellent anti-aging function and often used as an environmentally friendly topcoat coating. In order to understand its anti-corrosion performance and anti-corrosion mechanism for the purpose of expanding its application, the corrosion behavior and mechanism of intact acrylic powder coatings in marine environment and the defect of acrylic powder coating had been investigated using CASS test, immersion test and AC impedance method. Results showed that the transparent acrylic powder coatings with a thickness of 80 μm and 120 μm respectively had a few blisters on the edge of the scratch after treated by a 240 h CASS test. For the powder coating with a thickness of 120 μm, the maximum and minimum widths of corrosion products around the scratch were about 3.5 mm and 0.5 mm respectively, and the adhesion to the surface was level 0, indicating that the coating had good CASS resistance. After an immersion of 30 d, the amount of corrosion products generated around the scratch of 120 μm coating was smaller than that of 80 μm coating, revealing that 120 μm coating had better immersion resistance. Furthermore, the EIS of scratch specimens in 0.6 mol/L NaCl solution showed that the electric double layer capacitance decreased rapidly firstly and then tended to be stable, and the corrosion rate increased with the prolonging of immersion time. The impedance of the intact acrylic powder coating decreased from about 1010～1011Ω·cm2 to 106 Ω·cm2 after an immersion in 0.6 mol/L NaCl solution for 720 h. The barrier effect of these two kinds of coatings was basically the same after a 360 h immersion. Besides, as the aluminum alloy material covered with acrylic powder coating had poor corrosion resistance, the acrylic powder coating was not suitable to be used alone as the coating system for the automobile aluminum wheel hub or the alumimum alloy material. Hence, it is recommended to use composite coating system as the coating scheme for automobile aluminum alloy wheel hub.

The water treatment experiment for rust layer stabilization for Q500qENH weathering steel was carried out in seven different locations for 8 weeks to determine the applicability of the optimal treatment process. Results showed that with the prolonging of the stabilization treatment period, the weight loss and corrosion thinning of the samples increased, the corrosion rate presented a downward trend, and the color of the rust layer on the surface of the samples changed from orange to brown. In addition, the thickness of the rust layer increased gradually. The electrochemical analysis results indicated that the self - corrosion current density of the samples decreased, and the self - corrosion potential gradually shifted positively with the prolonging of the stabilization treatment period. Meanwhile, the results of XRD analysis revealed that the unstable phase (γ - FeOOH) gradually transformed into stable phase (α - FeOOH), and the proportion of stable phase (α - FeOOH) gradually increased with the extension of stabilization treatment period. To sum up the above results, Q500qENH weathering steel was treated by different rust layer stabilization water treatment processes in 3 kinds of typical locations, and a relatively stable rust layer could be obtained after 4～6 weeks.

The recovery of gold from water is an important research area. Recent reports have highlighted the ultrahigh capacity and selective extraction of gold from electronic waste using reduced graphene oxide (rGO). Here, we made a further attempt with the thermal rGO membranes and found that the thermal rGO membranes also had a similarly high adsorption efficiency (1.79 g gold per gram of rGO membranes at 1000 ppm). Furthermore, we paid special attention to the detailed selectivity between Au3+ and other ions by rGO membranes. The maximum adsorption capacity for Au3+ ions was about 16 times that of Cu2+ ions and 10 times that of Fe3+ ions in a mixture solution with equal proportions of Au3+/Cu2+ and Au3+/Fe3+. In a mixed-ion solution containing Au3+:Cu2+:Na+:Fe3+:Mg2+ of printed circuit board (PCB), the mass of Au3+:Cu2+:Na+:Fe3+:Mg2+ in rGO membranes is four orders of magnitude higher than the initial mass ratio. A theoretical analysis indicates that this selectivity may be attributed to the difference in the adsorption energy between the metal ions and the rGO membrane. The results are conducive to the usage of rGO membranes as adsorbents for Au capture from secondary metal resources in the industrial sector.

The vapor-phase antibacterial activity of essential oils makes them suitable for applications in air disinfection and other fields. At present, vapor-phase antibacterial activity of plant-based essential oils has rarely been reported. Herein, we report a new approach to investigate the antimicrobial activity and mechanism of vapor-phase cinnamaldehyde using Escherichia coli (E. coli) and three other pathogenic bacteria (Pseudomonas aeruginosa, Salmonella, Staphylococcus aureus) as model bacteria. Plate fumigation and agar block transfer techniques were used to determine the antimicrobial activities of vapor-phase cinnamaldehyde fumigation on the four types of bacteria, and the mechanism of action was determined by electrical conductivity (EC), OD260nm measurement, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and fluorescence spectroscopy. Cinnamaldehyde had good vapor-phase antibacterial activity against the four types of bacteria. The TEM, EC, and OD260nm measurements showed that after fumigation with cinnamaldehyde, the ultrastructures of the cells were damaged, and plasmolysis, cell collapse, and leakage of intracellular substances were observed. The FTIR and fluorescence spectroscopy analyses showed that the secondary and tertiary structures of bacterial membrane proteins were altered. These findings indicate that the cell membrane is an important target for plant-based essential oils to exert their vapor-phase antimicrobial effects. The results showed that plant-based essential oils can be developed as volatile broad-spectrum disinfection products and vapor-phase antiseptics.

Objective To investigate the effect of WeChat platform combined with problem-based learning (PBL) teaching method in standardization training for proctology specialist. Methods Totally 60 medical specialists who required standardization training were randomly divided into two groups, with 30 cases in each group. The observation group adopted wechat platform combined with PBL teaching method, while the control group adopted traditional teaching method. After teaching, the written test, operation skill and clinical competency were evaluated comprehensively. Results Scores of written test and operation skill in the observation group were higher than those in the control group (P＜0. 05). All indicators of clinical competence including reasoning ability, information processing capability, interpersonal communication skills and overall coordination ability in the observation group were higher than those in the control group (P＜0. 05). Conclusion WeChat platform combined with PBL teaching method in the standardization training can significantly improve the theoretical knowledge mastery and practical operation skills of specialists. The combined teaching method contributes to the establishment of standardized thinking mode in clinical diagnosis and treatment. (目的 探讨微信平台联合以问题为基础的学习(PBL)教学法在肛肠学科规范化培训教学中的应用效果。方法 将60例规范化培训学员随机分为观察组和对照组, 各30例。对照组采用传统教学法, 观察组采用微信平台联合PBL教学法。比较2组培训考核成绩以及临床胜任力。结果 观察组笔试和技能操作成绩均得分均高于对照组, 差异有统计学意义(P＜0. 05)。观察组临床推理能力、信息处理能力、人际交流能力、整体协同能力得分均高于对照组, 差异有统计学意义(P＜0. 05)。结论 微信平台联合PBL教学法在肛肠学科住院医师规范化培训中应用效果显著, 有助于提高规范化培训医生的理论知识掌握能力和实践操作技术水平, 帮助建立规范的临床诊疗思维模式。)

Enterocytozoon bieneusi is a zoonotic pathogen commonly found in humans and animals all over the world. Here, we investigated the occurrence and genotype constitute of E. bieneusi among the individuals from Haikou city of Hainan, China. A total of 1,264 fecal samples of humans were collected, including 628 samples from patients with diarrhea (325 adults and 303 children) and 636 samples from the asymptomatic population (383 college students and 253 kindergarten children). E. bieneusi was detected using nested polymerase chain reaction (PCR) amplification of the internal transcribed spacer (ITS) region. A phylogenetic tree was constructed using a neighbor-joining tree construction method. The overall prevalence of E. bieneusi was 3.7% (47/1,264), while it was 5.6% in the patients with diarrhea (5.8% in adults and 5.3% in children) and 1.9% in the asymptomatic population (2.9% in college students and 0.4% in kindergarten children). The prevalence of E. bieneusi in humans with diarrhea was significantly higher than that in the asymptomatic population (χ2 = 36.9; P < 0.05). A total of 28 genotypes were identified, including ten known genotypes: CHG2 (n = 3), CHG3 (n = 5), CHG5 (n = 10), CM21 (n = 1), EbpA (n = 1), EbpC (n = 1), PigEBITS4 (n = 1), PigEBITS7 (n = 1), SHR1 (n = 4), Type IV (n = 2), and 18 novel genotypes (HNH-1 to HNH-18; one each). All these genotypes were categorized into three groups, including group 1 (n = 6), group 2 (n = 14), and group 13 (n = 8). This was the first study on the identification of E. bieneusi among humans in Hainan, China. The correlation between E. bieneusi infection and diarrhea was observed. The high diversity and distinctive distribution of E. bieneusi genotypes found in this study reflected the unique epidemic genetic characteristics of E. bieneusi in humans living in Hainan.

Peters anomaly is a congenital condition which results in a central corneal opacity from birth. Selective Endothelial Removal (SER) is a novel surgical technique and a form of regenerative therapy, which encourages clearance of the central corneal opacity by the patient’s own corneal endothelial cells, and it may potentially be beneficial for the treatment of Peters anomaly. We have performed a phase I/II surgical trial, evaluating the safety of SER in four eyes (three patients) with Peters Anomaly. These patients underwent SER at between 9 and 39 months of age, each demonstrating clearance of central corneal opacities and improvements in vision post-operatively. No complications occurred in any of these eyes, at a minimal post-operative follow-up duration of 48 months. We conclude that SER for Peters anomaly is a safe surgical procedure. While encouraging efficacy outcomes have been observed, these findings should be further evaluated in a larger scale Phase II/III surgical trial.

Abstract Background Enterocytozoon bieneusi, a microsporidian species, is a zoonotic pathogen found in both humans and animals. Here, we determined the prevalence, explored the different genotypes of E. bieneusi in wild rhesus macaques (Macaca mulatta) (Hainan Island of China), and assessed their zoonotic potential. Methods We collected 173 fecal specimens from wild rhesus macaques living in Nanwan Monkey Island, Hainan, China. Subsequently, we identified and genotyped E. bieneusi using nested PCR analysis amplification of the internal transcribed spacer region (ITS) of the rRNA gene. Lastly, a neighbor-joining tree was built based on gene sequences from the ITS region of E. bieneusi. Results Of the 173 specimens from wild rhesus macaques, 26 (15%) were infected with E. bieneusi. We identified six genotypes of E. bieneusi, of which five were known: PigEBITS7 (n = 20), D (n = 2), Type IV (n = 1), Peru6 (n = 1), Henan-III (n = 1), and a novel genotype: HNM-IX (n = 1). From the phylogenetic analysis, the six genotypes identified here were all clustered into zoonotic group 1. Conclusion This study is the first report to detect E. bieneusi infection in wild rhesus macaques from Hainan, China. Human-pathogenic genotypes D, Henan-III, Peru6, PigEbITS7, and Type IV in the wild rhesus macaques support these animals infected with E. bieneusi have a public health significance.

Long noncoding RNA OPA-interacting protein 5 antisense transcript 1 (OIP5-AS1) was confirmed to involve in the malignancy of breast cancer. However, whether exosomal OIP5-AS1 is implicated in trastuzumab resistance remains unclear.

Abstract The corneal endothelium located on the posterior corneal surface is responsible for regulating stromal hydration. This is contributed by a monolayer of corneal endothelial cells (CECs), which are metabolically active in a continuous fluid-coupled efflux of ions from the corneal stroma into the aqueous humor, preventing stromal over-hydration and preserving the orderly arrangement of stromal collagen fibrils, which is essential for corneal transparency. Mature CECs do not have regenerative capacity and cell loss due to aging and diseases results in irreversible stromal edema and a loss of corneal clarity. The current gold standard of treatment for this worldwide blindness caused by corneal endothelial failure is the corneal transplantation using cadaveric donor corneas. The top indication is Fuchs corneal endothelial dystrophy/degeneration, which represents 39% of all corneal transplants performed. However, the global shortage of transplantable donor corneas has restricted the treatment outcomes, hence instigating a need to research for alternative therapies. One such avenue is the CEC regeneration from endothelial progenitors, which have been identified in the peripheral endothelium and the adjacent transition zone. This review examines the evidence supporting the existence of endothelial progenitors in the posterior limbus and summarizes the existing knowledge on the microanatomy of the transitional zone. We give an overview of the isolation and ex vivo propagation of human endothelial progenitors in the transition zone, and their growth and differentiation capacity to the corneal endothelium. Transplanting these bioengineered constructs into in vivo models of corneal endothelial degeneration will prove the efficacy and viability, and the long-term maintenance of functional endothelium. This will develop a novel regenerative therapy for the management of corneal endothelial diseases.

In order to study the shear-flow coupling characteristics of joints under constant normal stiffness (CNS) boundary condition, the shear-flow coupling tests under three different stiffness and seepage pressure settings were carried out for duplicate joint specimens with three different joint roughnesses. Meanwhile, the effects of normal stiffness, seepage pressure and joint roughness on the mechanical properties and seepage characteristics in joint shearing process were systematically analyzed. The test results indicate that the peak shear strength of joint increases with the increasing of normal stiffness, while the flow rate, equivalent hydraulic aperture and transmissivity decrease with the increasing of normal stiffness; and the flow rate of seepage through joint surfaces decreases during shearing process with the increasing of joint roughness. Similar to the three-stage change rule of joint dilatancy, three distinct stages are also observed for the flow rate, equivalent hydraulic aperture and transmissivity: rapid growth stage, slow growth stage, and stable stage. During the stable stage, the flow rate has approximately a linear relation with the variations of the normal stiffness and seepage pressure. The joints with higher roughness present lower flow rate as the seepage pressure increases.

The present work aimed to explore the protective effect of APSP on Pb-induced reproductive toxicity and possible mechanism. APSP (100 mg/kg) was administered to Pb-intoxicated (0.2% lead acetate) male Kunming mice once daily by oral gavage for 6 weeks. Our results showed that APSP exerted male reproductive protection effects as showed by attenuated Pb-induced testicular injury, improved sperm count and motility, and reduced sperm abnormality rate. APSP also restored Pb-induced decrease in both enzymatic and non-enzymatic antioxidants, and GSH/GSSG ratio, but inhibited lipid peroxidation in serum and testes. Moreover, APSP downregulated Pb-induced Bax mRNA and protein expressions, suppressed activation of caspase-3, upregulated Bcl-2 protein expression, and prevented Pb-induced DNA damage. APSP treatment also interfered with Pb-induced testicular JNK signaling through inhibition of JNK mRNA expression and phosphorylation, resulting in inhibition of c-Jun expression. These effects of APSP were abolished by Pb. In conclusion, APSP represents a potential therapeutic agent for preventing Pb-caused reproductive toxicity, which is attributed to its antioxidant and anti-apoptotic properties, as well as, modulation of JNK signaling pathway.

Enterocytozoon bieneusi is a microsporidian and zoonotic species. This study investigated the prevalence and distribution of E. bieneusi genotypes in farmed masked palm civets using nested PCR, as well as assessed their zoonotic potential by phylogenetic analysis of the ITS region of the rRNA region. Here, we collected 251 fecal specimens from farmed masked palm civets (Paguma larvata) from the Hainan Island, China. In total, 128 of 251 samples were positive for E. bieneusi, with an average infection rate of 51.0%. Seventeen genotypes were identified including 12 known genotypes—HNR-VI (n = 56), SHR1 (n = 45), SHW7 (n = 6), KIN-1 (n = 3), D (n = 3), New1 (n = 3), EbpC (n = 2), CHC5 (n = 1), CHG19 (n = 1), CHN4 (n = 1), EbpA (n = 1), and Henan-III (n = 1)—and five novel genotypes (HNPL-I to HNPL-II; one each). Phylogenetic analysis categorized these genotypes into two groups. Thirteen of them were members of the zoonotic group 1, and the remaining four genotypes were in group 12. This study has shown that the infection rates of E. bieneusi in masked palm civets from Hainan were relatively high and provide baseline data to control and prevent microsporidiosis in farm-related communities. Therefore, infections in masked palm civets with zoonotic genotypes D, EbpC, CHN4, EbpA, KIN-1, and Henan-III should be considered potential threats to public health.

The ion-enrichment inside carbon nanotubes (CNTs) offers the possibility of applications in water purification, ion batteries, memory devices, supercapacitors, field emission and functional hybrid nanostructures. However, the low filling capacity of CNTs in salt solutions due to end caps and blockages remains a barrier to the practical use of such applications. In this study, we fabricated ultra-short CNTs that were free from end caps and blockages using ball milling and acid pickling. We then compared their ion-enrichment capacity with that of long CNTs. The results showed that the ion-enrichment capacity of ultra-short CNTs was much higher than that of long CNTs. Furthermore, a broad range of ions could be enriched in the ultra-short CNTs including alkali-metal ions (e.g., K+), alkaline-earth-metal ions (e.g., Ca2+) and heavy-metal ions (e.g., Pb2+). The ultra-short CNTs were much more unobstructed than the raw long CNTs, which was due to the increased orifice number per unit mass of CNTs and the decreased difficulty in removing the blockages in the middle section inside the CNTs. Under the hydrated-cation–π interactions, the ultra-short CNTs with few end caps and blockages could highly efficiently enrich ions.

The continental shale oil reservoir has low permeability, high clay content, rich lamellar structure, and strong heterogeneity, which makes the reservoir vulnerable to hydration damage. In order to study characteristics of hydration damage and its influence on permeability of lamellar shale oil reservoirs, a series of experiments such as high-pressure mercury injection, steady gas permeability, rock thin section identification, and scanning electron microscope were carried out with the downhole core in Ordos Basin as the experimental object. The effects of water and water-based drilling fluid on pore size distribution, permeability, and rock microstructure were analyzed. Results show that the pore size of the reservoir is mainly nanoscale, and the pore size of shale changes most dramatically in the stage of hydration for 12-24 hours, while that of tuff changes most dramatically in 24-48 hours. The permeability increases rapidly with hydration time and then tends to be stable, among which the permeability of samples with lamellar structure in the direction parallel to the lamellar structure is most easily affected by hydration and changes fastest. Hydration leads to the formation of new pores, new fractures, and the expansion of existing fractures in rocks, especially in the strata containing large amounts of terrigenous clastic, lamellar structure, and pyrite. The new seepage channel increases the permeability of rock, and the soil powder and plugging particles in drilling fluid are easy to form protective mud cake in these places. These protective mud cakes not only change the microstructure of rock but also inhibit the influence of hydration on the pore space and permeability of rock, which play an effective role in preventing the mineral shedding on the rock surface, reducing the increase of micropores and delaying hydration.

Nuclear factor, erythroid 2 like 2 (Nrf2), is an oxidative stress induced transcription factor that regulates cytoprotective gene expression. Thus, Nrf2 is essential for cellular redox homeostasis. Loss or dysregulation of Nrf2 expression has been implicated in the pathogenesis of degenerative diseases, including diseases of the cornea. One of the most common diseases of the cornea in which Nrf2 is implicated is Fuchs’ endothelial cornea dystrophy (FECD). FECD is the leading indication for corneal transplantation; and is associated with a loss of corneal endothelial cell (CEC) function. In this review, we propose that Nrf2 is an essential regulator of CEC function. Furthermore, we demonstrate that deficiency of Nrf2 function is a hallmark of FECD. In addition, we advocate that pharmacological targeting of Nrf2 as a possible therapy for FECD.

We studied the nuclear shape evolutions in fission process of 240Pu by the time-dependent Hartree-Fock approach with various Skyrme forces. Calculations are performed for the later phase of the fission with large initial deformations toward the scission. We show that calculations with Skyrme forces with large surface energies and large symmetry energies can have extremely long fission evolution time. The symmetry energy plays a role in the evolution of neutron-rich necks. In addition, we also demonstrated the shape oscillations of fission fragments after the fission. We see that particularly the heavy near-spherical fragments have remarkable octupole oscillations.

Bulk metallic glasses (BMGs) possess excellent mechanical properties yet poor efficient processing ability at room temperature which limits the application of BMGs. Here, we report a high efficiency and energy-saving punching method suitable for processing of BMGs. By use of ultrasonic vibration on the punch, the accurate shape can be quickly manufactured from a BMG plate with a thickness upon 1 mm at an extremely low punch pressure of 110 MPa, which is less than one tenth of the estimated value by conventional theory. The underline physical mechanism of softening in BMG during the ultrasonic vibration assisted punching process was interpreted by cyclic liquefaction or the activation and connection of liquid-like regions in the elastic matrix of BMGs. This work would provide a novel route for solving the machining problem of BMGs at room temperature and promote wider applications of BMGs in precision manufacturing field. Keywords: Punching, Ultrasonic vibration, Bulk metallic glasses, Cyclic liquefaction

A novel low-profile dual-polarization frequency-selective rasorber (FSR) with a transmissive window in the absorption band is proposed in this paper. Based on the equivalent circuit model (ECM), the principles of the impedance design are theoretically derived. Then, a two-layer structure model is constructed. The top layer is composed of a lossy three-legged loaded element (TLLE), and the bottom layer is composed of a square ring bandpass frequency-selective surface (FSS). Furthermore, the strips are folded to reduce the unit cell size to stabilize the angular response. The maximum stable response angle increases from 20 to 40° due to the miniaturized design under both TE and TM polarization. The experimental results of the prototype are in good agreement with the simulation results, which validates the rationality of our design.

Carbon substrate-supported nano-TiO2 (a manufactured material) was prepared in this study for arsenic removal. The removal rates of arsenic were evaluated by batch tests under several simulation conditions including pH, ionic strength, and adsorbent dosage. Results showed that As(III) and As(V) adsorption reached equilibrium within 10 hours (pH = 8 and ionic strength 0.5 mol/L). At pH = 8, maximum adsorption efficiency was discovered for the adsorbent. Removal rate was proportional to the increase in ionic strength. The removal data were satisfactorily fitted to the pseudo-second-order kinetic model (R2 > 0.9990) and Freundlich equation (R2 ≥ 0.9600) for adsorption thermodynamic behaviors. New material showed more effective adsorption performance for As(V) than for As(III). It was found that 15.1800 mg/g As(V) and 13.3800 mg/g As(III) were adsorbed, respectively. In addition, material properties were studied including the structure of crystallinity, surface morphology, functional groups, and surface texture by XRD, TEM/SEM, FTIR, and BET methods, respectively. XRD result showed supported nano-TiO2 had the anatase phase. The size of the microparticle was around 52 nm. BET results indicated that material surface areas, pore volume, and pore size diameter were 371.17 m2/g, 0.35 cm3/g, and 11.70 nm, respectively. FTIR spectrum indicated that several functional groups (OH−, Ti-O) existing in supported nano-TiO2 may facilitate the adsorption efficiency. Mechanistically, supported nano-TiO2 played a key role in promoting adsorption efficiency and converting As(III) to As(V). Results indicated that the investigated adsorbents possessed an excellent arsenic removal capability.

The impact fracture mechanics of the cantilever beam-column specimens with different inclination angles(0°,30°,60°) prefabricated cracks subjected to hammer impact loading were studied by using digital dynamic caustic test system.The results show that the specimen with prefabricated crack of 0° reaches the fracture toughness first and starts to crack.Along with inclination angle increases,the energy accumulated at the crack tip becomes difficult,result in the initiation time is longer;The angle of crack has a great influence on the crack propagation trajectory,the bigger the angle is,the bigger the crack curving is.The increase of crack inclination leads to the vibration amplitude of the crack propagate rate increase and the average crack propagation rate increase,which indicates the influence of slanting crack on the velocity is larger than that of straight crack;With the inclination angle of prefabricated crack increases,the dynamic fracture toughness KICd gradually decreases, KIICd gradually increases and the composite characteristic becomes more obvious.The results provide a guidance for the prediction of crack propagating trajectory and the dynamic response of structure with cracks.

Climate change is increasing the frequency and severity of short-term (~1 y) drought events-the most common duration of drought-globally. Yet the impact of this intensification of drought on ecosystem functioning remains poorly resolved. This is due in part to the widely disparate approaches ecologists have employed to study drought, variation in the severity and duration of drought studied, and differences among ecosystems in vegetation, edaphic and climatic attributes that can mediate drought impacts. To overcome these problems and better identify the factors that modulate drought responses, we used a coordinated distributed experiment to quantify the impact of short-term drought on grassland and shrubland ecosystems. With a standardized approach, we imposed ~a single year of drought at 100 sites on six continents. Here we show that loss of a foundational ecosystem function-aboveground net primary production (ANPP)-was 60% greater at sites that experienced statistically extreme drought (1-in-100-y event) vs. those sites where drought was nominal (historically more common) in magnitude (35% vs. 21%, respectively). This reduction in a key carbon cycle process with a single year of extreme drought greatly exceeds previously reported losses for grasslands and shrublands. Our global experiment also revealed high variability in drought response but that relative reductions in ANPP were greater in drier ecosystems and those with fewer plant species. Overall, our results demonstrate with unprecedented rigor that the global impacts of projected increases in drought severity have been significantly underestimated and that drier and less diverse sites are likely to be most vulnerable to extreme drought.

Several decades after the development of acoustic stealth technology for ships, there remains an urgent necessity to reduce low frequency structural and acoustic response due to excitation from the stern. This paper reviews research into the coupled vibration and acoustic problems of the sterns of vessels. Attention is especially paid to three key aspects: the characteristics of propeller forces, the vibration-acoustic signatures of coupled propeller-shaft-hull systems, and vibration/noise controls. Therefore, the mapping relationships of vibration noise from the stern excitation and propeller-shaft-hull system is obtained, and the control approaches for low frequency vibration noise is presented. Thereafter, several suggestions are made for further research work in the testing technology of the unsteady force of propellers, the structural vibration induced by the stern bearing friction and the vibration control of propeller-shaft systems in the future.

The dynamic fracture behavior of notched semi-circular bending(NSCB) subjected to hammer impact loading was studied by using caustics experimental method.The results show that the shear stress at the crack tip increased with the offset distance increased, and correspondingly, the crack changed from mode I to mixed mode I-II, the time from impact force loaded to crack initiation also increased, moreover, the crack deflecting angle became more fluctuating with crack propagation;the crack velocity increased rapidly under dynamic load until it reached a certain value with continual fluctuation, with the ratio of crack vertical displacement to the total vertical lengthλ> 0.8, the crack velocity sharply decreased because of the effect of the local compressive stress around the hammer;as the offset distance increased, the initial fracture toughness KIC decreased, whereas KIIC increased;while the dynamic propagation toughness increased gradually with crack propagation.

The dynamic viscoelastic behavior and phase morphology of high impact polystyrene (HIPS)/high density polyethylene (HDPE) blends were investigated by dynamic rheological test and scanning electron microscopy (SEM). The compatibilizing effect of 1%(mass fraction, same as below) micron-CaCO3 and nano-CaCO3 on HIPS/HDPE(30/70) immiscible blend was compared. The results indicate that the complex viscosity and storage modulus of HIPS/HDPE blends at low frequencies show positive deviation from the mixing rule when HDPE is less than 30%, while negative deviation is observed when HDPE is more than 30%. The former is related to the interaction between HDPE and PB particles and the latter is attributed to the poor interfacial interaction between HDPE matrix and PS particles. When HIPS is the matrix phase, HDPE particles display broad size distribution. When HDPE acts as a matrix phase, PS dispersed phase exhibits bimodal size distribution corresponding to the presence of two different types of PS dispersed particles. 1% nano-CaCO3 has a certain compatibilizing effect on HIPS/HDPE(30/70) immiscible blend, which is mainly located at HIPS/HDPE interface and in the HDPE matrix, while micron-CaCO3 acts as viscosifier rather than compatibilizer, which is confined in the HDPE matrix.

Atomic force microscopy allows for the imaging of molecules at a nanometre resolution. Here the authors combine AFM with self-assembling DNA origami structures to detect single-nucleotide polymorphisms and determine haplotypes.

Summary: The hepatitis C virus (HCV) is a major cause of chronic liver disease, affecting around 71 million people worldwide. Viral RNA replication occurs in a membranous compartment composed of double-membrane vesicles (DMVs), whereas virus particles are thought to form by budding into the endoplasmic reticulum (ER). It is unknown how these steps are orchestrated in space and time. Here, we established an imaging system to visualize HCV structural and replicase proteins in live cells and with high resolution. We determined the conditions for the recruitment of viral proteins to putative assembly sites and studied the dynamics of this event and the underlying ultrastructure. Most notable was the selective recruitment of ER membranes around lipid droplets where structural proteins and the viral replicase colocalize. Moreover, ER membranes wrapping lipid droplets were decorated with double membrane vesicles, providing a topological map of how HCV might coordinate the steps of viral replication and virion assembly. : Lee et al. visualized likely HCV assembly in live cells and with high resolution. During assembly, HCV structural proteins relocalize to the viral replicase and together induce the wrapping of lipid droplets by ER membranes. These membranes are linked to the viral replication organelle, allowing spatial coordination of replication and assembly. Keywords: replication organelle, double-membrane vesicles, correlative light and electron microscopy, CLEM, HCV, lipid metabolism, virus–host interaction, assembly, lipid droplet, plus-strand RNA virus