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Due to the huge impact of temperature on mechanical and tribological properties of polymer composites, polyimide composites reinforced with glass fiber and aramid fiber were fabricated. The composites were treated by the alternate temperature from-50 °C to 150 °C with 200 cycles. The comparation of the test results were analyzed and discussed before and after alternate temperature treatment.

HIV-1 is a highly host-specific retrovirus that infects humans but not most nonhuman primates. Thus, the lack of a suitable primate model that can be directly infected with HIV-1 hinders HIV-1/AIDS research. In the previous study, we have found that the northern pig-tailed macaques (NPMs) are susceptible to HIV-1 infection but show a nonpathogenic state. In this study, to understand this macaque–HIV-1 interaction, we assembled a de novo genome and longitudinal transcriptome for this species during the course of HIV-1 infection. Using comparative genomic analysis, a positively selected gene, Toll-like receptor 8, was identified with a weak ability to induce an inflammatory response in this macaque. In addition, an interferon-stimulated gene, interferon alpha inducible protein 27, was upregulated in acute HIV-1 infection and acquired an enhanced ability to inhibit HIV-1 replication compared with its human ortholog. These findings coincide with the observation of persistently downregulated immune activation and low viral replication and can partially explain the AIDS-free state in this macaque following HIV-1 infection. This study identified a number of unexplored host genes that may hamper HIV-1 replication and pathogenicity in NPMs and provided new insights into the host defense mechanisms in cross-species infection of HIV-1. This work will facilitate the adoption of NPM as a feasible animal model for HIV-1/AIDS research.

BACKGROUND AND AIMS Vascular calcification (VC) is considered to be an important initiating risk factor of cardiovascular events, which contributes to the leading cause of death in maintenance hemodialysis (MHD) patients. VC has a high incidence and has been reported to predict the mortality of MHD patients. Inspired by an extreme example of VC in dialysis patients, calciphylaxis (which involves extensive calcification of small- and medium- arteries with poor prognosis), we hypothesized that VC of branches was a better predictor of mortality than abdominal aortic calcification. Therefore, a cohort study based on MHD patients was constructed to investigate the distribution characteristics of VC, compare the predictive value of VC on mortality among different arteries, and explore a comprehensive model predicting mortality. METHOD A total of 1583 patients in our Blood Purification Center from January 2015 to September 2017 were screened, and 237 eligible patients were finally included. Abdominal-pelvic computed tomography images were collected and an open-source software 3D Slicer (version 4.11) was used to calculate the calcification volume in abdominal aorta, celiac trunk, superior and inferior mesenteric artery, renal artery, common iliac artery and internal iliac artery. Demographic and clinical data including medical history and some laboratory indexes were collected. Patients were followed-up until all-cause death or September 2020. Cause of death and survival time were recorded in detail. The area under the curve (AUC) of Time-dependent receiver operating curves (ROC) was calculated to evaluate the predictive value of arterial calcification. 80% of cases were randomly assigned to the training dataset and the remaining were assigned to the validation dataset. Lasso regression was performed to screen variables. Cox proportional hazards regression was performed to construct the predicting model and nomogram. C-index, calibration and decision curve analysis were used to evaluate the comprehensive model. SPSS software (version 26.0) and R software (version 4.1.2) perform statistical analysis. RESULTS The prevalence of total VC is 95.36%. Among the abdominal arteries, abdominal aortic calcification is the most prevalent (88.61%), followed by calcification of internal iliac artery (85.65%) and common iliac artery (80.17%). Median survival time was 37.00 (1.00–70.00) months. The 1-year survival rate, 3-year survival rate and 5-year survival rate were 73.42%, 50.01% and 35.43%, respectively. Cardiovascular disease accounts for 54.01% of the death cause. AUC of Time-dependent ROC by internal iliac artery and mesenteric artery calcification for predicting mortality is significantly higher than that of other arterial calcification. Internal iliac artery calcification (IIAC) was screened out as the most representative predictor for all-cause death among the calcification of arterial calcification by lasso regression. When analyzing IIAC and other clinical data, age (hazard ratio 1.03, P CONCLUSION This is the first study evaluating the calcification volume of abdominal aortic branches and comparing their predictive values. In conclusion, calcification of abdominal aortic branches, especially internal iliac artery, is a better predictor for mortality of HD patients than abdominal aortic calcification. Our concern with calcification of large arteries in MHD patients needs to be shifted to smaller branch arteries.

BACKGROUND AND AIMS Warfarin is a common anticoagulant drug. How to effectively reduce vascular calcification induced by warfarin while ensuring its anticoagulant effect is an urgent problem to be solved. Previous studies have found that warfarin enhances the expression and activity of transglutaminase 2 (TG2) in vascular smooth muscle cells (VSMCs), which mediates communication between cells and extracellular matrix (ECM). Matrix vesicles (MVs) are the center of hydroxyapatite crystal precipitation, which is released to ECM and interacts with ECM protein to initiate mineralization and form calcification core. This study observed the role of the warfarin-TG2-MVs axis in vascular calcification by culturing VSMCs in vitro. METHOD VSMCs were cultured in normal or osteogenic medium (OM) and stimulated with 10 μm warfarin for 3–14 days. The expressions of SM22α, Runx2, ALP, OPN and OPG were detected by RT-PCR and western blot. Alizarin red and von Kossa staining were performed to evaluate calcification, and calcium content was determined. Meanwhile, the expression and activity of TG2 were detected. Differential centrifugation was used to extract MVs and evaluate their release. Type I collagen was coated in the culture dish to determine the calcification of MV-collagen. RESULTS Warfarin stimulation promoted transdifferentiation of VSMCs, and the expression of osteogenic factors Runx2, ALPL and OPN were increased, while the expression of SM22α and calcification inhibitor OPG were decreased. When using OM, the above trend was more obvious. Alizarin red and von Kossa staining were performed when the cells were cultured for 14 days. The results of calcium staining in the warfarin intervention group were all positive. Warfarin promoted the expression and activity of TG2, and it gradually increased with the extension of the intervention time. The same number of cells were cultured for 7 days under different stimuli, and the medium was changed every other day. Then, the supernatant was collected for differential centrifugation. The amount of MVs produced by the warfarin and OM groups was significantly higher than that of other groups, and the ability to mineralize of MVs in type I collagen was increased. CONCLUSION Warfarin increased the expression and activity of TG2, promoted the release of MVs from VSMCs, and further cross-linked ECM to aggravate vascular calcification.

BACKGROUND AND AIMS Calciphylaxis is a rare life-threatening syndrome. Although sodium thiosulfate (STS) showed clinical improvement, some patients presented with serious adverse events and withdrew from treatment. The optimized STS approach included four features: repeated treatment courses, small initial dose, once daily, and escalating low-to-moderate dose. The optimized STS approach, named ‘Zhong Da STS Therapy’ (Zhong Da: the name of a hospital, affiliated with Southeast University, School of Medicine, Nanjing, Jiangsu, China), was generalized with four features: repeated treatment courses, small initial dose, daily medicine, and daily escalating low-to-moderate dose of STS. STS from the initial dose (5 g) was administered intravenously once daily escalating to the highest daily dose as a maintenance dose (no more than 10 g). This study retrospectively evaluated the efficacy and safety of optimized STS therapy for calciphylaxis in China. METHOD The medical records of maintenance hemodialysis or CKD patients who were first diagnosed with calciphylaxis and received STS treatment at Zhong Da Hospital affiliated to Southeast University between October 2017 and October 2019 were retrospectively evaluated. The exclusion criteria of this retrospective study were death at the time of diagnosis (retrospectively confirmed cases) and did not receive the optimized STS approach treatment. The data to evaluate the efficacy included the changes in skin lesions, pain relief, survival rate and laboratory data. Adverse events were summarized as safety parameters. RESULTS The mean age was 51.10 ± 14.85 years old and 71% of patients were male. By October 2019, 87.1% of patients survived, 74.2% markedly improved and 41.9% of patients were followed up for more than 1 year with 100% survival. About 27 (87.10%) patients had typical skin lesions with 66.70% ulceration and skin lesions showed a predominantly peripheral distribution. After the first course, skin lesions improved by 77.8%, and 38.1% of pain sufferers were free from analgesics. The reduction of the Numerical Pain Rating Scale (NPRS) (P CONCLUSION Optimized STS therapy is a promising approach for calciphylaxis patients because it is relatively safe and associated with good outcomes.

The authors have requested that this preprint be removed from Research Square.

Skeletal muscle atrophy is prevalent and remarkably increases the risk of cardiovascular (CV) events and mortality in hemodialysis (HD) patients. However, whether diaphragm dysfunction predicts clinical outcomes in HD patients is unknown. This was a prospective cohort study of 103 HD patients. After assessment of diaphragm function by ultrasonography and collection of other baseline data, a 36-month follow-up was then initiated. Participants were divided into diaphragm dysfunction (DD+) group and normal diaphragm function (DD−) group, according to cutoff value of thickening ratio (i.e. the change ratio of diaphragm thickness) at force respiration. The primary endpoint was the first nonfatal CV event or all-cause mortality. A secondary endpoint was less serious CV events (LSCEs, a composite of heart failure readmission, cardiac arrhythmia or myocardial ischemia needed pharmacological intervention in hospital). 98 patients were eligible to analysis and 57 (58.16%) were men. 28 of 44 patients(63.64%) in DD+ group and 23 of 54 patients (42.59%) in DD− group had at least one nonfatal CV event or death (p = 0.038). Compared to DD− group, DD+ group had significantly higher incidence of LSCEs (21 vs.14, p = 0.025) and shorter survival time (22.02 ± 12.98 months vs. 26.74 ± 12.59 months, p = 0.046). Kaplan–Meier analysis revealed significantly higher risks of primary endpoint (p = 0.039), and LSCEs (p = 0.040) in DD+ group. Multivariate hazard analysis showed that DD+ group had significantly higher risk of primary endpoint [hazard ratio (HR) 1.59; 95% confident interval (CI) 1.54–1.63], and LSCEs (HR 1.47; 95%CI 1.40–1.55). Ultrasound-assessed diaphragm dysfunction predicts clinical outcomes in HD patients.Trial registration: This study was registered with Chinese Clinical Trials Registry (www.chictr.org.cn) as ChiCTR1800016500 on Jun 05, 2018.

Background: Protein-energy wasting (PEW) and inflammation have been recognized as two major factors associated with the poor prognosis of patients with maintenance haemodialysis (MHD). The aim of this study was to evaluate the effects of oral fat based high-energy supplements (Fresubin) on malnutrition and inflammation in MHD patients. Method: This study was open-label, prospective, nonrandomized and comparative. A total of 47 MHD patients with PEW were randomly assigned into 2 groups: a control group, and a Fresubin treatment group, in which patients received daily diet intake and Fresubin nutrient support 120 mL/d for 80 days. Laboratory data and anthropometric parameters were measured. Result: The results showed that compared with baseline, the level of serum albumin at 80 d in the Fresubin treatment group was significantly increased (35.4 ± 3.7 vs 38.9 ± 2.9, p = 0.003), while there was no significant difference in the control group. In addition, the magnitudes of changes in albumin (p = 0.009), serum prealbumin (p = 0.017), and abdominal circumference (p = 0.037) in the Fresubin treatment group were markedly increased compared with those in the control group. There was a downward trend in the inflammatory marker hypersensitive C-reactive protein in the Fresubin group (p =0.056), which decreased more dramatically than that in the control group (p = 0.026). Conclusion: Fresubin treatment is well tolerated, and improves malnutrition and inflammatory status in MHD patients with PEW.

Growing evidences have confirmed the effect of Sacubitril/Valsartan (SV) on antihypertension and cardiac protection in general population. However, there was no prospective study about the effect and safety of SV on resistant hypertension and myocardial work in hemodialysis patients. In this single-center, prospective, before-after study, enrolled patients were endured with resistant hypertension for more than 6 months. Participants were initially instructed to take SV 50 mg twice daily, and the dosage was gradually increased up to 100 mg twice daily. The primary outcomes were blood pressure (BP) control, N-terminal pro-B-type natriuretic peptide (NT-proBNP), myocardial work (MW), fatigue and life quality. In addition, the adverse events were also recorded in this cohort. A total of 18 patients (34-64 years old) was finally enrolled and completed in this study. The SV-based regimen provided significantly mean sitting systolic BP (msSBP) and mean sitting diastolic BP (msDBP) reductions from baseline (-20.7/-8.3 mm Hg), respectively. The cardiac remodeling parameters were partially improved. Compared to the baseline, NT-proBNP was significantly reduced at week 4 (8119.50 [3710.75, 29300] pg/ml to 7216.50 [4124.75, 17455.00] pg/ml, p = .046), which was much lower at week 12 (3130.50 [2244.50, 9565.70] pg/ml, p = .037). Global MW index was higher at week 12 compared to the baseline (p = .026). MW efficiency was also improved accordingly compared to the baseline, even though the statistical difference was not significant (p = .226). Life quality and fatigue were improved at week 12 compared to the baseline (all p = .000). There was no serious adverse events were observed. SV safely and effectively controlled resistant hypertension and improved MW as well as life quality in hemodialysis patients.

Nonlinear optical properties of tetraphenylporphyrin (H2TPP) and protonated tetraphenylporphyrin (H4TPP2+) in toluene were investigated by Z-scan technique using a nanosecond laser with 5 ns pulse at 532 nm. Results show that H4TPP2+ exhibits weaker nonlinear refraction but enhanced reverse saturable absorption (RSA) and optical limiting performance in comparison with pristine H2TPP. Since no nonlinear scattering is observed in H4TPP2+ under low input fluence, and H4TPP2+ exhibits weaker nonlinear scattering signals than H2TPP under high input fluence, the enhancement of RSA and optical limiting performance can be attributed to the larger ratio of excited state absorption cross-section to that of the ground state of H4TPP2+. H4TPP2+ also exhibits superior optical limiting performance, even better than the benchmark RSA material C60.

BackgroundAntibiotics are among the most frequently prescribed medications. Many studies suggest an increased risk of health care–associated infections (HAIs) among antibiotic users. However，most related studies have focused only on a single type of HAIs, but considering the complexity and extent of the subject, it is necessary to conduct extensive research. We conducted a case-control study to determine the association between antibiotic combination therapy and risk of HAIs. MethodsRetrospective case-control study in a teaching hospital in Northwest China. Cases of 216 patients were diagnosed as HAIs during hospitalization between January 2019 and December 2019. Use antibiotics on admission and before the occurrence of HAIs were compared with 428 patients without HAIs during the same period, and matched by department.ResultsNinety-one of 216 health care–associated infections, 157 of 428 Patients without health care–associated infections prescribed antibiotics on admission and before the occurrence of HAIs. After multi-variable analysis, Compared with patients without HAIs, the OR for antibiotics combination exposure in cases was 5.43 [95% confidence interval (CI) 2.62-11.24], and the OR for antibiotics exposure in cases was 0.23 (95% CI 0.12-0.43).Conclusions Combined use of antibiotics increases the risk of HAIs. In addition, Use of antibiotics before the diagnosis of HAIs is conducted associated with HAIs, and is the main protective factor.

This paper addresses the region-reaching control problem for a flexible-joint robotic manipulator which is formulated by Lagrangian dynamics. An adaptive control scheme is proposed for the manipulator system having two constrained regions which are constructed by selecting appropriate objective functions. The two joints of the flexible-joint manipulator can be, respectively, confined in different regions, and this gives more flexibility than the traditional fixed-point tracking control. By performing a straightforward Lyapunov stability analysis, a simple control algorithm is established to provide a solution for the region-reaching control problem. Finally, numerical simulations are given to validate the theoretical results.

Background and Aims Endothelial progenitor cells (EPCs) patrol the circulation and contribute to endothelial cell regeneration and tissue revascularization. Atherosclerotic renal artery stenosis (ARAS) induces microvascular loss in the stenotic kidney. A regimen of low–energy shockwave therapy (SW) induces angiogenesis and reduces chronic ischemia, but the mechanism remains unclear. This study tested the hypothesis that SW increases EPCs homing to the stenotic kidney and increases renal capillary regeneration in a unilateral ARAS swine model. Method Domestic pigs were randomized to normal control or unilateral ARAS (induced by a local irritant coil in the renal artery and a high-fat diet). ARAS pigs were treated with low-energy SW (0.1 mJ/mm2) or sham (n=6 each group), bi-weekly for 3 consecutive weeks, starting after 3 weeks of ARAS. Blood samples for EPCs (CD34+ and KDR+ by flow cytometry) and the homing factor SDF-1 were collected 4 weeks after completion of SW treatment from the inferior vena cava (IVC) and the stenotic kidney (STK) vein and artery. Urine was collected from the urinary bladder. Kidneys were studied ex vivo for morphology and expression of an endothelial cell marker (CD31) and the pro- angiogenic growth factor angiopoietin (Ang)-1. Results In ARAS, tubulointerstitial fibrosis, tubular score, urinary protein, serum creatinine and mean arterial pressure were significantly increased and capillary count (Fig. 1A) decreased (P Conclusion Low-energy shockwave improves ischemic kidney capillary density, which is associated with and may be at least in part mediated by promoting EPC mobilization and homing to the stenotic kidney.

Due to insufficient mechanical performance, such as low tensile strength, the application of hydroxyapatite (HA)/high-density polyethylene (HDPE) biocomposites has been limited to use as minor load-bearing bone substitutes. In the current work, we propose to impose an intense shear flow during injection molding to tune the microstructure of the HA/HDPE biocomposites, by which an anisotropic biomimetic structure and superior mechanical properties were gained. Morphological observations manifested that the imposed intense shear induced a large amount of oriented self-reinforced superstructure, i.e., interlocked shish-kebabs, which brought not only structure similarity with the natural bone but also considerable mechanical reinforcement. For the 20 wt% HA/HDPE biocomposite, the tensile strength and bending strength of the structured sample rose from 22.4 and 20.2 MPa for the normal sample to 60.4 and 44.0 MPa, increasing by 169% and 118%, respectively, which already reaches the bounds of human cortical bone. The Young's modulus increased to 1462.0 MPa, with an augment of 37%. The impact toughness of the structured biocomposite (64.6 kJ m−2) showed as over 5 times larger than the normal biocomposite (10.1 kJ m−2). Besides, the dispersion of the HA in the biocomposites especially at the high filler content was enhanced, playing a positive role in sustaining the bioactivity. All these results indicate that the structured HA/HDPE biocomposites hold great promise for use in high load-bearing orthopedic applications.

APOBEC3 family members, particularly APOBEC3F and APOBEC3G, inhibit the replication and spread of various retroviruses by inducing hypermutation in newly synthesized viral DNA. Viral hypermutation by APOBEC3 is associated with viral evolution, viral transmission, and disease progression. In recent years, increasing attention has been paid to targeting APOBEC3G for AIDS therapy. Thus, a controllable model system using species such as macaques, which provide a relatively ideal in vivo system, is needed for the study of APOBEC3-related issues. To appropriately utilize this animal model for biomedical research, important differences between human and macaque APOBEC3s must be considered. In this study, we found that the ratio of APOBEC3G-mediated/APOBEC3-mediated HIV-1 hypermutation footprints was much lower in peripheral blood mononuclear cells (PBMCs) from northern pig-tailed macaques than in PBMCs from humans. Next, we identified a novel and conserved APOBEC3G pre-mRNA alternative splicing pattern in macaques, which differed from that in humans and resulted from an Alu element insertion into macaque APOBEC3G gene intron 1. This alternative splicing pattern generating an aberrant APOBEC3G mRNA isoform may significantly dilute full-length APOBEC3G and reduce APOBEC3G-mediated hypermutation pressure on HIV-1 in northern pig-tailed macaques, which was supported by the elimination of other possibilities accounting for this hypermutation difference between the two hosts.IMPORTANCE APOBEC3 family members, particularly APOBEC3F and APOBEC3G, are important cellular antiviral factors. Recently, more attention has been paid to targeting APOBEC3G for AIDS therapy. To appropriately utilize macaque animal models for the study of APOBEC3-related issues, it is important that the differences between human and macaque APOBEC3s are clarified. In this study, we identified a novel and conserved APOBEC3G pre-mRNA alternative splicing pattern in macaques, which differed from that in humans and which may reduce the APOBEC3G-mediated hypermutation pressure on HIV-1 in northern pig-tailed macaques (NPMs). Our work provides important information for the proper application of macaque animal models for APOBEC3-related issues in AIDS research and a better understanding of the biological functions of APOBEC3 proteins.

The potential influence of coexisting nonhydrogen species on hydrogen permeation through metallic membranes is critically reviewed considering five issues: dilution effect, concentration polarization (external diffusion resistance), competitive adsorption, irreversible poisoning effect, and surface catalytic effect. The irreversible poisoning effects of typical species such as H2S, CO, and NH3 on hydrogen permeation are subsequently discussed. Some development strategies are presented for the improved chemical stability of metallic membranes.

The potential degradation of coexisting nonhydrogen species on hydrogen permeation through Pd membranes is investigated with experimental and simulation methods. The apparent experimental results show that hydrogen flux in H2–Y binary mixtures would deviate from that of a pure hydrogen atmosphere. During mixture separation tests, there were different hydrogen permeation profiles along the axial coordinate of Pd tubular membranes and the nonhydrogen species did not change the hydrogen permeation mechanism of the Pd membrane.

In this paper, we propose a hybrid PML (H-PML) combining the normal absorption factor of convolutional PML (C-PML) with tangential absorption factor of Mutiaxial PML (M-PML). The H-PML boundary conditions can better suppress the numerical instability in some extreme models. and the computational speed of finite-element method and the dynamic range are greatly increased using this HPML. We use the finiteelement method with a hybrid PML to model the acoustic reflection of the interface when wireline and well logging while drilling (LWD), in a formation with a reflector outside the borehole. The simulation results suggests that the PS- and SP- reflected waves arrive at the same time when the inclination between the well and the outer interface is zero, and the difference in arrival times increases with increasing dip angle. When there are fractures outside the well, the reflection signal is clearer in the subsequent reflection waves and may be used to identify the fractured zone. The difference between the dominant wavelength and the model scale shows that LWD reflection logging data are of higher resolution and quality than wireline acoustic reflection logging.

Viral reservoirs of HIV-1 are a major obstacle for curing AIDS. The novel animal models that can be directly infected with HIV-1 will contribute to develop effective strategies for eradicating infections. Here, we inoculated 4 northern pig-tailed macaques (NPM) with the HIV-1 strain HIV-1NL4.3 and monitored the infection for approximately 3 years (150 weeks). The HIV-1-infected NPMs showed transient viremia for about 10 weeks after infection. However, cell-associated proviral DNA and viral RNA persisted in the peripheral blood and lymphoid organs for about 3 years. Moreover, replication-competent HIV-1 could be successfully recovered from peripheral blood mononuclear cells (PBMCs) during long-term infection. The numbers of resting CD4+ T cells in HIV-1 infected NPMs harboring proviruses fell within a range of 2- to 3-log10 per million cells, and these proviruses could be reactivated both ex vivo and in vivo in response to co-stimulation with the latency-reversing agents JQ1 and prostratin. Our results suggested that NPMs can be infected with HIV-1 and a long-term viral reservoir was formed in NPMs, which might serve as a potential model for HIV-1 reservoir research.

The effects of the pre-deformation on the microstructure, mechanical properties and corrosion resistance of Al–Cu–Mg–Ag alloys were investigated by means of hardness tests, tensile tests, intergranullar corrosion (IGC) tests and transmission electron microscopy (TEM), respectively. The results show that with the increase of deformation amount, the aging hardening rate increases while the strength of the alloy decreases and then increases. The sample with a pre-deformation of 6% possesses the highest tensile strength due to the refinedly and homogeneously distributed precipitations. The pre-deformation aging accelerates the heterogeneous nucleation of Ω and θ′ phases at dislocations, and also refines the precipitations both in the grains and along the grain boundaries. The precipitation of Ω phase is restrained while that of θ′ phase is accelerated in pre-deformed Al–Cu–Mg–Ag alloy compared with the sample without pre-deformation. In addition, the width of the precipitate free zone decreases with increasing the pre-deformation amount, leading to a narrower IGC passageway. This results in an enhanced IGC resistance of Al–Cu–Mg–Ag alloy treated by pre-deformation aging.

The effects of serials of electric parameters (i.e. electric pulsed current, electric pulse width, etc.) on machining speed and surface quality were investigated. Furthermore the selected parameters in electrical discharge machining (EDM) were optimized. Experiments indicate that the machining speed of EDM increases with the increasing of pulse current and pulse width. On the other side, the surface quality decrease with the increasing of pulse current and pulse width.

APOBEC3 family members, particularly APOBEC3F and APOBEC3G, inhibit the replication and spread of various retroviruses by inducing hypermutation in newly synthesized viral DNA. Viral hypermutation by APOBEC3 is associated with viral evolution, viral transmission, and disease progression. In recent years, increasing attention has been paid to targeting APOBEC3G for AIDS therapy. Thus, a controllable model system using species such as macaques, which provide a relatively ideal in vivo system, is needed for the study of APOBEC3-related issues. To appropriately utilize this animal model for biomedical research, important differences between human and macaque APOBEC3s must be considered. In this study, we found that the ratio of APOBEC3G-mediated/APOBEC3-mediated HIV-1 hypermutation footprints was much lower in peripheral blood mononuclear cells (PBMCs) from northern pig-tailed macaques than in PBMCs from humans. Next, we identified a novel and conserved APOBEC3G pre-mRNA alternative splicing pattern in macaques, which differed from that in humans and resulted from an Alu element insertion into macaque APOBEC3G gene intron 1. This alternative splicing pattern generating an aberrant APOBEC3G mRNA isoform may significantly dilute full-length APOBEC3G and reduce APOBEC3G-mediated hypermutation pressure on HIV-1 in northern pig-tailed macaques, which was supported by the elimination of other possibilities accounting for this hypermutation difference between the two hosts. IMPORTANCE APOBEC3 family members, particularly APOBEC3F and APOBEC3G, are important cellular antiviral factors. Recently, more attention has been paid to targeting APOBEC3G for AIDS therapy. To appropriately utilize macaque animal models for the study of APOBEC3-related issues, it is important that the differences between human and macaque APOBEC3s are clarified. In this study, we identified a novel and conserved APOBEC3G pre-mRNA alternative splicing pattern in macaques, which differed from that in humans and which may reduce the APOBEC3G-mediated hypermutation pressure on HIV-1 in northern pig-tailed macaques (NPMs). Our work provides important information for the proper application of macaque animal models for APOBEC3-related issues in AIDS research and a better understanding of the biological functions of APOBEC3 proteins.

Background: The neuroinflammatory responses of microglial cells play an important role in the process of brain dysfunction caused by heat stroke. MicroRNAs are reportedly involved in a complex signaling network and have been identified as neuroinflammatory regulators. In this study, we determined the biological roles of microRNA-155 in the inflammatory responses in heat-stressed microglia and explored the underlying mechanisms. Methods: MicroRNA-155 mimic and inhibitor were used to separately upregulate or downregulate microRNA-155 expression. The activation state of BV-2 microglial cells (BV-2 cells) was assessed via immunoreactions using the microglial marker CD11b and CD68. Levels of induced interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were measured using real-time reverse transcription polymerase chain reaction (RT-PCR) and enzyme linked immunosorbent assays (ELISAs). The activation of nuclear factor kappa B (NF-κB) signaling proteins was evaluated by Western blotting for inhibitory kappa B alpha (IκBα) and NF-κB p65 phosphorylation and indirect immunofluorescence analysis using a p65 phosphorylation antibody. A luciferase reporter assay was used to verify liver X receptor α (LXRα) as a target gene of microRNA-155. Results: Heat stress significantly induced IL-1β, IL-6, and TNF-α release and increased the expression of CD11b and CD68. In addition, IκBα and NF-κB p65 phosphorylation were dramatically increased by heat stress, and microRNA-155 expression was also elevated. High expression of microRNA-155 in heat-stressed microglial cells was inversely correlated with LXRα expression. We then determined the role of microRNA-155 in the heat stress-induced inflammatory responses. The results revealed that by targeting LXRα, microRNA-155 enhanced NF-κB signaling activation and facilitated immune inflammation in heat stress-treated BV-2 cells. Conclusion: MicroRNA-155 promotes heat stress-induced inflammatory responses in microglia. The underlying mechanisms may include facilitating inflammatory factors expression by increasing NF-κB pathway activation via targeting LXRα.

GO/CNTs composite membranes with fine hierarchical nanostructure were facilely fabricated by intercalation with 1D carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) into 2D graphene oxide (GO) nanosheets for efficient organic wastewater treatment. By characterization results of XRD, Raman, FTIR, TEM and water contact angle, MWCNTs-COOH was successfully to be intercalated into GO lamellar interlayers with grafting reactions, which would improve water permeated flux and stability of membrane. The influences of GO/CNTs ratios, loading amounts, CNTs types and support types on the membrane separation performance were systematically investigated towards methylene blue dye solution. For the GO/CNTs composite membranes prepared under the optimized conditions, the permeated flux of 34.4 L m−2 h-1 and rejection over 99.7 % were obtained towards methylene blue solutions under the transmembrane pressure difference of 0.9 bar, respectively. Compared with pristine GO membrane, it exhibited a nearly 10-fold water permeated flux improvement meanwhile maintaining high rejection. Moreover, the electrostatic interaction and size exclusion effects were synergistically contributed to be responsible for the efficiently separation properties of the GO/CNTs membranes towards different positively/negatively charged dyes and neutral organic molecules. Such the GO/CNTs membranes also exhibited good chemical stability for acid resistance with highly efficient separation performance.

A simple method to fabricate one-dimensional (1-D) and two-dimensional (2-D) ordered micro- and nano-scale patterns is developed based on the original masters from optical discs, using nanoimprint technology and soft stamps. Polydimethylsiloxane (PDMS) was used to replicate the negative image of the 1-D grating pattern on the masters of CD-R, DVD-R and BD-R optical discs, respectively, and then the 1-D pattern on one of the PDMS stamps was transferred to a blank polycarbonate (PC) substrate by nanoimprint. The 2-D ordered patterns were fabricated by the second imprinting using another PDMS stamp. Different 2-D periodic patterns were obtained depending on the PDMS stamps and the angle between the two times of imprints. This method may provide a way for the fabrication of complex 2-D patterns using simple 1-D masters.

In this paper, influence of density on the microstructure, mechanical properties, thermal and electrical properties of recrystallized silicon carbide (RSiC) were investigated via XRD, SEM, mechanical test, thermal conductivity instrument and four-probe method, etc. The results showed that the main phase of the RSiC materials was 6H-SiC; The flexural strength and modulus of elasticity of RSiC materials increased with the increase of densities, and the flexural strength of it measured at 1400 °C increased about 10%-15% compared with that of at room temperature, while the modulus of elasticity at 1400°C were lower than that of at room temperature, resulting from the weakening of binding force between the Si and C atoms at high temperature; With the increase of temperatures, the thermal conductivity of the RSiC materials decreased, while it increased with the increase of RSiC density, when density of RSiC equaled to 2.60 g·cm­3, values of the thermal conductivity were 177.7 W·(m·K)­1 (RT) and 28.1 W·(m·K)­1(1300°C), respectively; The volume resistivity of RSiC materials dropped from 12.74 Ω·cm to 4.51 Ω·cm as the density of RSiC increased, the impurities played an more important role on this variety.

By adjusting mass fraction of Ni-Al composite additive in Ti-B4C primary system, a series of TiB2-based ceramic composites were prepared by combustion synthesis in high gravity field. Because the adiabatic temperature of the whole reaction system maintained a constant in the presence of mass fraction of Ni-Al additive smaller than 18.55%, increasing mass fraction of Ni-Al additive to be 15% brought about the improved homogeneity in refined microstructure of the enhanced-densification TiB2-based composite, so flexural strength and fracture toughness of the ceramic composite increased simultaneously due to the enhanced self-toughening mechanisms contributed by a number of fine TiB2 platelets.

Chronic immune activation and systemic inflammation are underlying causes of acquired immunodeficiency syndrome (AIDS). Products of virus replication and microbial translocation, co-infection or opportunistic pathogens, and danger-associated molecular patterns have been reported to contribute to chronic immune activation and inflammation in human immunodeficiency virus type-1/simian immunodeficiency virus (HIV-1/SIV) infection or other disease. To develop new strategies and therapies for HIV-1/AIDS, we tested if the CD24 and Fc fusion protein (CD24Fc), which interacts with danger-associated molecular patterns and sialic acid binding Ig-like lectin to attenuate inflammation, can protect Chinese rhesus macaques (ChRMs) with SIV infection. We found that CD24Fc treatment decreased weight loss, wasting syndrome, intractable diarrhea, and AIDS morbidity and mortality, while it was well tolerated by SIV-infected animals. Corresponding to the elimination of intractable diarrhea, CD24Fc significantly reduced the expression of IL-6 and indoleamine 2, 3-dioxygenase-1 in peripheral blood mononuclear cell and inflammation in the ileum, colon and rectum based on the reduction of inflammatory cells, pathological scores and expression of inflammatory cytokines. Furthermore, although CD24Fc did not restore CD4+ T cell number or significantly change T cell subsets or CD4+ T cell activation, it maintained low levels of plasma soluble CD14, CD8+ T cell activation, viral load and proviral load in the peripheral blood mononuclear cells and marrow. These results suggested that CD24Fc confers protection to SIV-infected ChRMs against progression to AIDS. It was also implied that CD24Fc may be a potential therapeutic approach for the control of HIV-1/AIDS.

Chinese rhesus macaques (CRMs) are ideal experimental animals for studying the pathogenesis of human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) and for vaccine research. SHIV89.6 has been reported to be an attenuated virus because, in most cases, SHIV89.6 infection only causes limited alteration of immune cells and tissues, and it has been used commonly for vaccine research. After two serial passages in vivo, SHIV (SHIV-89.6P) induces CD4 lymphopenia and an AIDS-like disease with wasting and opportunistic infections. However, the pathogenic ability of SHIV89.6 is not well understood. In this study, we found that 6 of 14 SHIV89.6-infected CRMs died within 127 weeks after infection. We found especially high immune activation, low IFN-α expression, and distinctive cytokine expression profiles in the infected and dead (ID) group of monkeys, while there was only few change in the CD4(+) T counts and distribution of T cell subsets in the ID group monkeys. Also, there was a similar dynamic of viral load between infected and surviving (IS) and ID group monkeys. Furthermore, we found various correlations among immune activation, IFN-α expression, and frequencies of cytokine-secreting cells. These results suggest that SHIV89.6 infections have pathogenic potential in CRMs and that high immune activation and abnormal expression of cytokines contribute to death of SHIV89.6-infected CRMs. This also implies that high immune activation may be relevant to dysfunction of immune cells. It is proposed that high immune activation and dysfunction of immune cells may be good predictors for disease progression and markers for therapy.

Stable porphyrin-oxygenated carbon nanomaterial dispersions were prepared by blending porphyrin solutions with hydroxyl groups modified multi-walled carbon nanotubes (MWNTs-OH) and graphene oxide (GO) dispersions, respectively. Optical nonlinearity and optical limiting (OL) property of these blends are investigated in nanosecond regime. Results show that the OL performance of the blends can be tuned by changing the concentrations ratio of porphyrin and oxygenated carbon nanomaterials. The high concentration of oxygenated carbon nanomaterial leads to the poor OL performance. However, with the moderate concentration, the blends exhibit the low threshold value of OL and the enhanced OL performance at high fluence region. The superior OL performance can be attributed to complementary mechanisms and possible photoinduced electron or energy transfer between porphyrin moiety and oxygenated carbon nanomaterials.

The idea of preparing the surface of chitosan layer pre-absorbed on the monodispers porous microsphere via layer by layer approach receives special relevance in enzyme technology. Moreover, the colloidal stability is not impeded by the adsorbed proteins despite the fact that up to 390.2 mg of enzyme adsorbed per gram of the carrier particles. Maximum relative activity was observed at 50 °C and pH 3.5. The activity half lives for native and bound states of enzyme were found as 14.27 d and 31.05 d, respectively. These particles, premodified with the layer of magnetic nanoparticles to impart the magnetic property, were repeatedly used as catalysts following their rapid and easy separation.

As companies rely more and more on information systems, security of database becomes increasingly important. The database has a security mechanism to ensure completeness and correctness, however attackers or unauthorized users always want to operate database through non-formal ways. Therefore, it’s important to record user’s operations worked on the database. This paper puts forward a new way to record user’s actions in the audit system, which accesses to the network through the bypass monitoring method, this way audits database by setting the policy. The advantages are that the audit system does not affect the communication between the client and the database server, and database problem does not affect the database audit system. In this paper, Oracle database communication protocol TNS will be example to describe the audit system. This paper also introduces TNS in the protocol framework and shows its level position, then designs a framework for the audit system according to the network model.

The elderly population infected with HIV-1 is often characterized by the rapid AIDS progression and poor treatment outcome, possibly because of immunosenescence resulting from both HIV infection and aging. However, this hypothesis remains to be fully tested. Here, we studied 6 young and 12 old Chinese rhesus macaques (ChRM) over the course of three months after simian immunodeficiency virus (SIV) SIVmac239 infection. Old ChRM showed a higher risk of accelerated AIDS development than did young macaques, owing to rapidly elevated plasma viral loads and decreased levels of CD4+ T cells. The low frequency of naïve CD4+ T cells before infection was strongly predictive of an increased disease progression, whereas the severe depletion of CD4+ T cells and the rapid proliferation of naïve lymphocytes accelerated the exhaustion of naïve lymphocytes in old ChRM. Moreover, in old ChRM, a robust innate host response with defective regulation was associated with a compensation for naïve T cell depletion and a high level of immune activation. Therefore, we suggest that immunosenescence plays an important role in the accelerated AIDS progression in elderly individuals and that SIV-infected old ChRM may be a favorable model for studying AIDS pathogenesis and researching therapies for elderly AIDS patients.

Spinel nickel ferrite (NiFe 2 O 4 ) nanoparticles with high specific area and excellent magnetic properties were synthesized via a template-assisted sol – gel method. The effects of template type on the structural properties, magnetic properties, and heating rate are investigated. Results of XRD and TEM indicate that the NiFe 2 O 4 particles synthesized using templates exhibit a typical single phase spinel structure in nano size. The sample using sponge or cotton as template presents the best saturation magnetization (66.6 emu/g) and the lowest coercivity (137.7 Oe), respectively, and their specific surface area is enhanced greatly from 20.1 m 2 /g to 55.7 m 2 /g. It is found that the calculated hysteresis loss agrees well with the measured radio frequency heating rate.

Regenerated cellulose (RCE)/poly(vinyl alcohol) (PVA) composite hydrogels were successfully prepared via physical repeated freezing and thawing method. The structure and properties of the RCE/PVA composite hydrogel were investigated by Fourier transform infrared spectrum, scanning electron microscopy, mechanical and swelling tests. The results revealed that a novel compact dual-network structure was formed between the cross-linked cellulose network and PVA matrix, which can strongly enhance the mechanical properties of the composite hydrogels as expected. Compared with neat PVA hydrogels, a 611% increase in tensile strength of RCE/PVA composite hydrogel from 0.09 to 0.64 MPa and 643% improvement in compressive strength from 0.07 to 0.52 MPa were achieved with the addition of 4 wt% of cellulose. The presence of cellulose is also beneficial to the elasticity of PVA hydrogels. With the incorporation of RCE, the composite hydrogels perform better shape recovery after compression test. Moreover, the addition o...

The root cause of the failure of a cracked blade in the low pressure turbine of a nuclear power plant was investigated. The low clearance between the blade and the disk caused a sliding motion, which led to fretting wear during in-service operations. The crack in the blade was determined to have initiated under fretting wear and propagated with high cycle fatigue by means of analyzing the fracture surface of the failed blade. Micro oxide particles were detected from the Electron Dispersive Spectroscopy data analysis at the fatigue initiation position as typical evidence of fretting wear. The stress distribution on the blade in normal service was calculated with a non-linear elastic–plastic finite element method. The analysis results show that the crack initiation location was different with the location of the highest Mises stress. The fretting fatigue crack initiated under a combination of fretting wear and relatively high Mises stress. Designed fretting fatigue experiments were performed with the results that the fatigue life was greatly reduced by the interaction of the loading history and local fretting wear.

This work presents an approach to realize hybrid damping passively on the basis of inerter-spring-damper system, and demonstrates a passive hybrid damping suspension system that offers the performances of skyhook and groundhook dampers, but without the need of an inertial frame. The design principle and method of the system are presented, and a full-car model is built to analyze and compare the performances of the conventional passive, ideal and passive hybrid damping suspensions. The results demonstrate that the ideal and passive hybrid damping suspensions have the quite consistent performance that they both can suppress body and wheel resonances. As a result, the presented suspension improves ride comfort and safety significantly. It therefore has a good comprehensive performance.

The influence of MoSi2 content on the microstructural, mechanical, and electrical properties of MoSi2–RSiC composites was studied. Results showed that the main phases in the MoSi2–RSiC composites were SiC, MoSi2 and Mo4.8Si3C0.6. When the MoSi2 content was below 10%, most of the Mo compounds coated the surface of the coarse SiC particles. At MoSi2 contents >10%, some Mo compounds coated the surface while others filled the pores near the sintering neck between the SiC particles. MoSi2 can also accelerate the re-crystallization process of RSiC. Increases in MoSi2 content resulted in decreases in the porosity of the composite; in contrast, the flexural strength initially increased and then decreased under the same conditions. The flexural strength reached 94.0 MPa when the MoSi2 content was 10%. With increasing MoSi2 content, the volume resistivity of the composites decreased steeply, the electrical conductivity mechanism of it resembled that of a two shunt-wound equivalent circuit.

Electrical Discharge Machining (EDM) is the machining technique of discharging corrosion of the material surface. The effect of the EDM pulse current on the micro structure and properties of the P20 specimen surface were investigated. Three layers were observed on the specimen surface after discharging: ablation layer, molten layer and recrystallized layer. The experimental results show that with the increment of the pulse current, the thickness of the molten layer and recrystallized layer increased. The contents of the oxygen and carbon on the outside of the molten layer were higher than the base metal for the diffusion during the machining. The micro hardness reduced from the out layer to the base metal after the heat treatment, indicating the mechanical properties changing of the machining surface. In the molten layer, micro fracture is caused by the residual thermal stress during the machining.