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Objective: This study was to evaluate measurement properties of the Chinese version of the Brief Inventory of Perceived Stress (BIPS-C) and confirm possible solutions for measuring the constructs underlying perceived stress. Methods: A total of 1356 community residents enrolled and were randomly split into two halves. The first half was used to explore the underlying constructs of the BIPS-C by exploratory graph analysis (EGA) and the second half was used to compare and confirm the constructs by confirmatory factor analysis (CFA). Results: The EGA identified a one-factor model of the BIPS-C with an accuracy of 99.3%. One-factor, three-factor, second-order, and bifactor models were compared by CFAs. The bifactor model with one general and three specific factors was found to be the most adequate [comparative fit index (CFI) = 0.990; Tucker-Lewis index (TLI) = 0.979; root mean square error of approximation (RMSEA) = 0.058] and was superior to the other models. The related bifactor indices showed a stronger existence of the general factor. The bifactor model of the BIPS-C also showed adequate internal consistency with McDonald's omega and omega subscales ranging from moderate to strong (0.677–0.869). Conclusion: The BIPS-C demonstrates sufficient measurement properties for assessing general perceived stress. [ABSTRACT FROM AUTHOR]

Large quantities of sand carried by crosswinds often settle in the cabin of diesel locomotives operating in desert regions. This study adopts an Euler-Lagrange two-phase flow model to simulate sand movement and deposition in a running diesel locomotive through the ventilation grilles. The realistic sand particle diameter distribution obtained from the field test is incorporated by the Rosin-Rummler model in computational fluid dynamics software. The realizable k-ε turbulent model is adopted to simulate the turbulence. The operation of the locomotive on a straight track at 200 km/h with five different crosswind velocities is studied numerically. The simulation results indicate that the increment of crosswind speed leads to higher pressure on the grille and the velocity of the internal flow field. The relationship between the number of sand particles trapped inside the car and the incident angle (i.e., resultant wind angle) is discovered. It is evident that the majority of sand particles enter the compartment through the windward tail grilles. Therefore, the influence of adjusting the tilt angle of the tail grille on the sand entering the locomotive cabin is calculated. It is discovered that the compartment experiences the least sand deposition at a 30° title angle. Therefore, optimizing the tilt angle of the frame for grilles can significantly enhance the filtering of the grille. [ABSTRACT FROM AUTHOR]

Context: In order to further improve the manufacturing technology of resonator facet of GaAs (gallium arsenide)-based laser, the scratching process of GaAs was simulated by molecular dynamics. Models of GaAs crystals with different orientations, including GaAs [100], GaAs [110], and GaAs [111], were generated, followed by scratch simulations on these models. The surface characteristics of scratches, damage width, subsurface damage, stack height, and the distribution and activity characteristics of dislocations were analyzed based on the simulation results. The results show that there are obvious anisotropy in the deformation of different crystal orientation during the scratching process of GaAs. Surface features, damage width, subsurface damage, and dislocation dynamics during scraping in GaAs crystals strongly depend on crystal orientation. It was also observed that GaAs exhibits distinct characteristics of dislocation activity during the scratching process, depending on its crystal orientation. In addition, GaAs [110] crystal direction has the smallest maximum damage width and subsurface damage depth. The maximum of maximum damage width is in GaAs [100] crystal direction, and the maximum subsurface damage depth is in GaAs [111] crystal direction. In addition, the stacking height is maximum when GaAs [100] is scraped and minimum when GaAs [110] is scraped. Methods: The engraving quality of GaAs materials was investigated utilizing the LAMMPS software through molecular dynamics simulations, while observations were facilitated using the OVITO software. The MD simulation was conducted employing the NPT ensemble, with the temperature fixed at 300 K. A time step of 2 fs was utilized, and the total duration of the MD simulation spanned 600 ps. [ABSTRACT FROM AUTHOR]

Basal cell carcinoma (BCC) is one of the most common malignancies worldwide, yet its genetic determinants are incompletely defined. We perform a European ancestry genome-wide association (GWA) meta-analysis and a Hispanic/Latino ancestry GWA meta-analysis and meta-analyze both in a multi-ancestry GWAS meta-analysis of BCC, totaling 50,531 BCC cases and 762,234 controls from four cohorts (GERA, Mass-General Brigham Biobank, UK Biobank, and 23andMe research cohort). Here we identify 122 BCC-associated loci, of which 36 were novel, and subsequently fine-mapped these associations. We also identify an association of the well-known pigment gene SLC45A2 as well as associations at RCC2 and CLPTM1L with BCC in Hispanic/Latinos. We examine these BCC loci for association with cutaneous squamous cell carcinoma (cSCC) in 16,407 SCC cases and 762,486 controls of European ancestry, and 33 SNPs show evidence of association. Our study findings provide important insights into the genetic basis of BCC and cSCC susceptibility. A large multi-ancestry genome-wide meta-analysis identifies novel basal cell carcinoma loci and shared genetic effects with squamous cell carcinoma, providing insight into the genetic basis of these serious forms of cancer. [ABSTRACT FROM AUTHOR]

Heteroepitaxy of GaAs on Si enables well-functioning III–V semiconductor lasers integrated onto silicon, solving the issue of lacking purely silicon-based light sources. Since GaAs has been the key material in many III–V laser structures, the Si-based GaAs epilayer should be of high quality which requires a low surface roughness and dislocation density. Herein, we demonstrate a high-quality heteroepitaxy of 1.84 μm GaAs on Si (001) substrates by molecular beam epitaxy. By virtue of multi-time thermal cycle annealing, the surface roughness was reduced to 1.74 nm within a scan area of 10 × 10 μm2, and the measured threading dislocation density was as low as 6.87 × 106/cm2. Periodic interfacial misfit dislocation arrays were found at the GaAs/Si interface with a misfit-dislocation-spacing distance of 9.6 nm. The formation of these arrays is attributed to the usage of thermal cycle annealing which makes near-interface TDs form into in-plane misfit dislocations. The demonstrated epitaxy scheme of growing such high-quality GaAs/Si virtual substrates provides a feasible way to fabricate III–V semiconductor lasers with enhanced performances. [ABSTRACT FROM AUTHOR]

Background: There are no universally accepted indications to initiate renal replacement therapy (RRT) among patients with acute kidney injury (AKI). This study aimed to develop a nomogram to predict the risk of RRT among AKI patients in intensive care unit (ICU). Methods: In this retrospective cohort study, we extracted AKI patients from Medical Information Mart for Intensive Care III (MIMIC-III) database. Patients were randomly divided into a training cohort (70%) and a validation cohort (30%). Multivariable logistic regression based on Akaike information criterion was used to establish the nomogram. The discrimination and calibration of the nomogram were evaluated by Harrell's concordance index (C-index) and Hosmer–Lemeshow (HL) test. Decision curve analysis (DCA) was performed to evaluate clinical application. Results: A total of 7413 critically ill patients with AKI were finally enrolled. 514 (6.9%) patients received RRT after ICU admission. 5194 (70%) patients were in the training cohort and 2219 (30%) patients were in the validation cohort. Nine variables, namely, age, hemoglobin, creatinine, blood urea nitrogen and lactate at AKI detection, comorbidity of congestive heart failure, AKI stage, and vasopressor use were included in the nomogram. The predictive model demonstrated satisfying discrimination and calibration with C-index of 0.938 (95% CI, 0.927–0.949; HL test, P = 0.430) in training set and 0.935 (95% CI, 0.919–0.951; HL test, P = 0.392) in validation set. DCA showed a positive net benefit of our nomogram. Conclusion: The nomogram developed in this study was highly accurate for RRT prediction with potential application value. [ABSTRACT FROM AUTHOR]

Tool sizes and material properties significantly influence the surface quality of micro grooves and the life of the milling tool in micro milling. Thus, expanding the application range of micro-milling tool sizes and exploring the milling performance of different materials are crucial for high-precision milling. In this study, the experimental research on in situ preparation and in situ milling was conducted using a self-developed high-precision combination machine tool. The preparation of D-shaped micro-milling tools with a diameter of 50 μm class was realized using a wire-cutting electrical discharge grinding technology. The performances of carbide, polycrystalline diamond (PCD)-coated carbide, and PCD tools during the micro-milling process of brass were investigated in terms of tool wear and workpiece surface finish. The results showed that the PCD micro-milling tool had the slightest wear, effectively inhabited burr generation, and had stable side wall and groove bottom processing capabilities compared with uncoated and coated PCD carbide micro-milling tools. In addition, the surface roughness of the PCD micro-milling tool was 41.9% lower than that of the carbide micro-milling tool, and high-precision machining with minimum roughness of 32.37 nm was realized. PCD micro-milling tool had excellent milling properties, which significantly prolonged tool life and improved machining quality and accuracy. [ABSTRACT FROM AUTHOR]

Solution precursor plasma-sprayed (SPPS) yttrium aluminum garnet (YAG) thermal barrier coatings (TBCs) have previously been shown to have higher temperature capability and reduced thermal conductivity compared to state-of-the- art TBCs. This previous work was conducted using a relatively low enthalpy plasma gun (Metco 9 MB) and TBCs were deposited on laboratory specimens. The primary goal of this work was to advance the state of technology readiness of SPPS YAG TBC coatings by using a high enthalpy cascaded arc gun (Sinplex Pro) to produce varied microstructures optimized for specific engine components: a fuel nozzle tip, an annular combustor liner, and turbine ceramic outer air seals. The microstructure and properties of these TBCs have been characterized and shown to be superior to those obtained previously. Based on these favorable results, the processing technology was transferred to solar turbines incorporated. Their process optimization of coatings for the three engine components and the rig and engine testing of the coated components will be described in Part II of this paper. [ABSTRACT FROM AUTHOR]

Background: Kidney dysfunction frequently occurred after orthotopic liver transplantation (OLT). Chronic renal disease (CKD) is a complicated problem and is associated with increased mortality. The aim of this study is to find the risk factors for the incidence of CKD at 1 year after OLT in China. Methods: From January 2017 to December 2017, we retrospectively assessed 280 recipients in our single center. Chronic renal failure was defined as estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2 for 3 months, regardless of the presence or absence of structural kidney damage. Cox proportional hazard model was used to identify the factors to the incidence of CKD after liver transplantations. Kaplan–Meier plots with log-rank test were presented to evaluate patient survival time in those with and without CKD. Results: With a median follow-up of 17.4 months, 48 patients developed CKD after liver transplantations, representing 17.1% of the cohort. The cox-regression model showed that recipients age (HR = 1.097, P < 0.01), AKI (HR = 1.542, P < 0.01) and MELD score (HR = 1.077, P < 0.01) were significantly associated with the development of post-transplant CKD at 1 year. Recipient survival at 1 year was significantly worse in recipients with CKD compared to those without CKD (P < 0.01) after adjustment by age and gender. Conclusion: Our findings suggested that age, AKI and MELD score were associated with the incidence of CKD 1 year after OLT in a Chinese cohort. Recipients with CKD were associated with worse survival. [ABSTRACT FROM AUTHOR]

Baiyacha (BYC) is a kind of wild tea plant growing and utilizing in the remote mountain area of Fujian province, Southeastern China. However, scientific studies on this plant remain limited. Our results showed that BYC exhibits the typical morphological characteristics of Camellia gymnogyna Chang, a closely related species of C. sinensis (L.) O. Kuntze, which was not found in Fujian before. Chemical profiling revealed that parts of BYC plants are rich in purine alkaloids and catechins, especially featuring high levels of theacrine and 3″-methyl-epigallocatechin gallate (EGCG3″Me), chemical compounds with multiple biological activities that are rarely observed in regular tea plants. The contents of EGCG3″Me and theacrine in BYC both increased with the leaf maturity of tea shoots, whereas the caffeine content decreased significantly. The obtained results provide abundant information about the morphology and chemical compounds of BYC and may be used for tea production, breeding, and scientific research in the future. [ABSTRACT FROM AUTHOR]

Gas turbine efficiency can be improved by increasing the operating temperature and by reducing the need for cooling air, both of which are enabled by higher temperature materials. Silicon carbide based ceramic matrix composites (CMCs) have shown promise for achieving higher temperatures. However, to survive in the high-temperature high-humidity combustion environment, environmental barrier coatings (EBCs) are essential to limit silicon loss of CMCs and its associated damage. Atmospheric plasma spray (APS) is a popular process for making such coatings. In this work, an alternative deposition process is explored, specifically the solution precursor plasma spray (SPPS), where it will be shown for ytterbium monosilicate EBCs that such process directly deposits thin (< 50 μm), dense and crystalline EBC topcoats without annealing of amorphous phases as is needed in the APS process. In addition, the SPPS process allows for quick compensation of system-specific element loss observed in both SPPS and APS processes. Finally, the secondary phase present in EBCs are much smaller in size for the SPPS process and hence less likely to produce cracking compared to APS EBCs. [ABSTRACT FROM AUTHOR]

Time-dependent reliability analysis (TRA) has drawn much attention due to its ability in measuring the probability that a system or component keeps safe in the full life cycle. Since it is difficult to efficiently obtain accurate results for TRA problems with expensive simulation demand, many surrogate model-based methods have been proposed to handle this challenge. Moreover, when both random and interval uncertainties are included in these TRA problems simultaneously, the analysis process will be more complicated. In this paper, two methods based on projection outline adaptive Kriging (POK) are proposed to handle TRA and TRA with mixed interval uncertainties (iTRA), respectively. Firstly, POK-TRA method is put forward for the TRA problems with different stochastic processes. Different from current TRA methods, POK-TRA regards the time parameter as a special interval variable, which converts TRA problem into a special hybrid reliability analysis (HRA) problem with one interval variable. Based on the concept of projection outline as well as a correlation condition, an efficient sampling strategy is proposed to refine the Kriging model adaptively. Secondly, POK-TRA is extended to the time-dependent reliability analysis including both random and interval variables (POK-iTRA). By inheriting the processing strategy of time parameter and stochastic processes, the iTRA problem is converted into the HRA problem with multiple interval variables. Finally, four cases are used to show the accuracy and efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

Support vector regression (SVR), as a promising surrogate model, has been widely used to approximate expensive simulations in engineering design problem. To build a SVR model accurately and efficiently, a two-stage support vector regression (TSSVR) assisted sequential sampling approach is proposed in this paper with the consideration of SVR’s two unique features. In each sampling iteration of TSSVR, two SVR models are constructed successively based on the same training data. As for the first feature that only support vectors (SVs) have impact on the construction of SVR, the first-stage SVR with lower ε precision is built to prescreen some important samples as current SVs. As for the second feature that SVR model does not completely go through the samples, the second-stage SVR with higher ε precision is built to calculate the prediction errors at the SVs without any other computational cost, and the prediction errors are used to approximately measure the accuracy of the local regions around the SVs. Moreover, to describe the local regions around the SVs, the design space is partitioned into a set of Voronoi cells according to the current samples before prescreening SVs from the sample points. Then a new sample can be exploited in the corresponding Voronoi cell with the largest prediction error. In the next sampling iteration, the Voronoi cells and SVs are redefined. As the change of the local cell with the largest prediction error, global exploration is achieved. Finally, the proposed approach is validated by seven numerical examples and an engineering example. An overall comparison between the proposed approach and some other methods demonstrates that the proposed approach is efficient and suitable for engineering design problems involving computational-expensive simulations. [ABSTRACT FROM AUTHOR]

Low thermal conductivity in yttrium aluminum garnet (YAG)-based thermal barrier coatings (TBCs) made by solution precursor plasma spray (SPPS) can be achieved by creating planar arrays of porosity called inter-pass boundaries (IPBs) as shown in Part I. In the current work, the mechanism of IPBs formation is studied through analysis of precursor entrainment and collection of single/raster step deposition patterns. It is concluded that the IPBs are formed by trapping precursor that under/over penetrates the plasma jet. CMAS interaction tests on SPPS YAG TBCs with heavy IPBs show an improvement of 123X and 15X over APS YSZ and SPPS YAG-light IPBs TBCs, respectively. It is demonstrated that the exceptional coating performance is because of the engineered heavy IPBs which branch out from the vertical cracks and run parallel to the surface. The CMAS melt gets drawn in the IPBs due to the capillary forces, leading to a shallow infiltration depth. The IPBs have a porosity of 70%, thus act as reservoirs for CMAS. Based on the favorable results, an alternate CMAS mitigation strategy is proposed that solely relies on microstructural features instead of the conventional approach where a vigorous reaction between CMAS-TBCs is desirable to form secondary phases. [ABSTRACT FROM AUTHOR]

Single-loop approach (SLA) is one of the most promising methods for solving linear and weakly nonlinear reliability-based design optimization (RBDO) problems. However, since SLA locates the current approximate most probable point (MPP) by using the gradient information of the previous one to reduce the computational cost, it may lead to inaccuracy when the nonlinearity of probabilistic constraints becomes relatively high. To overcome this limitation, a new adaptive hybrid single-loop method (AH-SLM) that can automatically choose to search for the approximate MPP or accurate MPP is proposed in this paper. Moreover, to get the accurate MPP more efficiently and alleviate the oscillation in the search process, an iterative control strategy (ICS) with two iterative control criteria is developed. In each iterative step, the KKT-condition of performance measure approach (PMA) is introduced to check the validity of the approximate MPP. If the approximate MPP is infeasible, ICS will be further carried out to search for the accurate MPP. The two iterative control criteria are used to update the oscillation control step length, then ICS can converge fast for both weakly and highly nonlinear performance functions. Besides, numerical examples are presented to verify the efficiency and robustness of our proposed method. [ABSTRACT FROM AUTHOR]

Our previous works presented experimental investigations of the brittle material removal fraction (BRF) on the machined surface of optical glass. It is related to the area fraction of brittle material removed on the machined surface and is used to assess the surface roughness of optical glass during precision grinding. In general, subsurface damage (SSD) is considered to be one of the most important machining qualities in grinding of optical glass. This work presents an experimental investigation of the relationship between BRF and SSD depth of optical glass during precision grinding to understand the significance of BRF on sensing the SSD of optical glass. A series of precision grinding experiments were conducted on a precision grinder machine to investigate the influence of grinding parameters on SSD depth. Based on an image processing algorithm developed in previous work, the BRF was calculated by using a microtopography image of a machined surface of K9 glass during precision grinding. The experimental results show that the BRF was determined for different machining parameters (cutting depth, wheel speed, and feed rate) and was dependent on SSD depth in precision grinding, which implies that the BRF has potential for application as a rapid and affordable online vision measurement approach to monitor surface and subsurface qualities during the grinding of brittle materials. [ABSTRACT FROM AUTHOR]

Ultrasound-assisted grinding (UAG) is generally considered as one of the most efficient and cost-effective techniques to machine optical glass. To understand the influence of the UAG parameters on the surface quality of optical glass, a series of experiments was conducted on a precision grinder machine assisted with an axial ultrasonic vibration device. On the basis of the mechanism of removal of hard, brittle materials, we propose a new surface-quality parameter for optical glass subjected to UAG: the brittle material removal fraction (BRF), which is related to the area fraction of brittle material removed from a machined surface. To calculate the BRF, an image-processing algorithm was developed by analyzing microtopographic images of the machined optical glass surface. The BRF was determined for different machining parameters (cutting depth, wheel speed, feed rate, and ultrasonic vibration amplitude) and was found to be dependent on the surface roughness. The grinding force measured in the UAG experiments exhibited a similar trend to the BRF with respect to the different machining parameters. Therefore, the BRF is a reasonable variable for estimating the surface quality of optical glass subjected to UAG. [ABSTRACT FROM AUTHOR]

Yttrium aluminum garnet thermal barrier coatings (TBCs) deposited by the solution precursor plasma spray process (SPPS) have been shown to have a 200 °C temperature advantage compared to air plasma spray yttria-stabilized zirconia TBCs (Gell et al. in J Therm Spray Technol 27:1-13, 2018). These properties were generated on specimens and included phase stability to 1900 °C, improved sinter resistance, reduced thermal conductivity, and enhanced CMAS resistance. Part I of this paper describes the development of the SPPS processing parameters with different microstructures for three solar engine components (fuel nozzle injectors, annular combustor, and turbine ceramic outer air seals). This Part II paper describes the technology transfer to Solar Turbines Incorporated, coating of the three components and the successful rig and engine tests. [ABSTRACT FROM AUTHOR]

Solution precursor plasma spray (SPPS) is a coating deposition process that uses conventional plasma spray equipment, and solution precursors, rather than ceramic or metal powders, as starting materials. Because the process is exposed to oxygen at high temperatures, nearly all coatings, to date, are oxide ceramics. In this review, both the advantages and the disadvantages of the SPPS process and some comparisons made to the suspension plasma spray (SPS) process will be discussed. The advantages of the SPPS process include rapid exploration of compositions and fabrication of advanced coatings with unique microstructural features. Examples presented span densities from porous thermal barrier coatings (TBCs) to dense TiO coatings. Two TBCs are in an advanced development stage: (1) a low thermal conductivity YSZ TBC and (2) a high-temperature yttrium aluminum garnet TBC. As for disadvantages, there are (1) the additional development work for each new precursor and (2) a lower standoff distance and deposition rate than the APS process, related to the evaporation of the solvent. The SPS process shares the same disadvantages. In developing new coatings, a number of factors should be considered and understood, which would help to shorten future development efforts. Future directions of the SPPS process will also be discussed. [ABSTRACT FROM AUTHOR]

Advanced thermal barrier coatings (TBCs) with lower thermal conductivity, increased resistance to calcium-magnesium-aluminosilicate (CMAS), and improved high-temperature capability, compared to traditional yttria-stabilized zirconia (YSZ) TBCs, are essential to higher efficiency in next generation gas turbine engines. Double-layer rare-earth zirconate/YSZ TBCs are a promising solution. From a processing perspective, solution precursor plasma spray (SPPS) process with its unique and beneficial microstructural features can be an effective approach to obtaining the double-layer microstructure. Previously durable low-thermal-conductivity YSZ TBCs with optimized layered porosity, called the inter-pass boundaries (IPBs) were produced using the SPPS process. In this study, an SPPS gadolinium zirconate (GZO) protective surface layer was successfully added. These SPPS double-layer TBCs not only retained good cyclic durability and low thermal conductivity, but also demonstrated favorable phase stability and increased surface temperature capabilities. The CMAS resistance was evaluated with both accumulative and single applications of simulated CMAS in isothermal furnaces. The double-layer YSZ/GZO exhibited dramatic improvement in the single application, but not in the continuous one. In addition, to explore their potential application in integrated gasification combined cycle environments, double-layer TBCs were tested under high-temperature humidity and encouraging performance was recorded. [ABSTRACT FROM AUTHOR]

Chalcogenide glasses of the GeSbSeI ( x = 0, 5, 10, 15, 20 at.%) system were prepared. This study was performed to examine some Ge-Sb-Se-I glass physical and optical properties, the structural evolution of the glass network, and the optical properties of the infrared glass fibers based on our previous studies. The variation process of the glass physical properties, such as transition temperature, glass density, and refractive index, was investigated from the glass of GeSbSe to the GeSbSeI glass series. The structural evolutions of these glasses were examined by Raman spectroscopy. The GeSbSeI composition was selected for the preparation of the IR fiber. The GeSbSeI glass was purified through distillation, and the intensity of the impurity absorption peaks caused by Ge-O, HO, and Se-H was reduced or eliminated in the purified glasses. Then, GeSbSeI chalcogenide glass fiber for mid-infrared transmission was fabricated using high-purity materials. The transmission loss of the GeSbSeI fiber was greatly reduced compared with that of the GeSbSe glass fiber. The lowest losses obtained were 3.5 dB/m at 3.3 μm for GeSbSeI fiber, which was remarkably improved compared with 48 dB/m of the unpurified GeSbSe fiber. [ABSTRACT FROM AUTHOR]

Objective: To analyze the efficacy of levonorgestrelintrauterine system, Drospirenone & ethinylestradiol tablets (II), and dydrogesterone in preventing the recurrence of endometrial polyps after hysteroscopic endometrial polypectomy. Methods: One hundred seventy patients who underwent hysteroscopic endometrial polypectomy in the Gynecology Department of Tianmen First People's Hospital in Hubei Province from January 2022 to June 2023 were randomly divided into the levonorgestrelintrauterine system group, Drospirenone & ethinylestradiol tablets (II) group, dydrogesterone group, and a control group. The recurrence rates, endometrial thickness, and menstrual volume changes at 6 and 12 months post-operation were compared among these four groups. Results: The recurrence rates in the levonorgestrelintrauterine system group, Drospirenone & ethinylestradiol tablets (II) group, and dydrogesterone group were lower than the control group, with statistical significance (P < 0.01), with the levonorgestrelintrauterine system group having the lowest recurrence rate. The endometrial thickness at 6 and 12 months post-operation in the levonorgestrelintrauterine system group, Drospirenone & ethinylestradiol tablets (II) group, and dydrogesterone group was thinner than that of the control group and thinner than pre-operation, with statistical significance (P < 0.01). The menstrual volume at 3 months post-operation in the levonorgestrelintrauterine system group, Drospirenone & ethinylestradiol tablets (II) group, and dydrogesterone group was significantly less than the control group, and less than the pre-operation volume. Conclusion: Dydrogesterone, drospirenone & ethinylestradiol tablets (II), and levonorgestrelintrauterine system all play a role in preventing the recurrence of endometrial polyps, but levonorgestrelintrauterine system is significantly better than dydrogesterone and Drospirenone & ethinylestradiol tablets (II) in terms of postoperative recurrence rate, endometrial thickness, menstrual changes, and compliance, and is worth promoting in clinical application. [ABSTRACT FROM AUTHOR]

The primary function of thermal barrier coatings (TBCs) is to insulate the underlying metal from high temperature gases in gas turbine engines. As a consequence, low thermal conductivity and high durability are the primary properties of interest. In this work, the solution precursor plasma spray (SPPS) process was used to create layered porosity, called inter-pass boundaries, in yttria-stabilized zirconia (YSZ) TBCs. IPBs have been shown to be effective in reducing thermal conductivity. Optimization of the IPB microstructure by the SPPS process produced YSZ TBCs with a thermal conductivity of 0.6 W/mK, an approximately 50% reduction compared to standard air plasma sprayed (APS) coatings. In preliminary tests, SPPS YSZ with IPBs exhibited equal or greater furnace thermal cycles and erosion resistance compared to regular SPPS and commercially made APS YSZ TBCs. [ABSTRACT FROM AUTHOR]

We examined the relationship between maternal depressive symptoms in late pregnancy and Epstein-Barr virus reactivation before delivery. In this prospective observational study, prevalence of Epstein-Barr virus reactivation within one week before delivery was compared between 163 pregnant women with depressive symptoms at 33 to 34 weeks of gestation and a computer-generated control group of 163 pregnant healthy women without depressive symptoms. Depressive symptoms at 33 to 34 weeks of gestation were significantly related to the prevalence of Epstein-Barr virus reactivation before delivery after adjustment for potential confounders (adjusted OR52.74, 95%CI: 1.23-6.08). Compared to that in the control group, the prevalence of Epstein-Barr virus reactivation was higher in women with depressive symptoms accompanied by higher negative coping (24.2% compared with 7.9%; adjusted OR53.67, 95%CI: 1.47-9.16). Maternal depressive symptoms in late pregnancy are associated with Epstein-Barr virus reactivation, and this association could be moderated by maternal coping style. [ABSTRACT FROM AUTHOR]

To machine a noncoaxial nonaxisymmetric aspheric lens, a new parallel grinding method that employs a fixture with an adjustable gradient (AGF) is proposed. The AGF is developed for a three-axis computer numerically controlled grinding machine. The grinding method is presented according to the proposed grinding system. To ensure the machining accuracy, the main machining errors and the compensation algorithm are discussed for the grinding method using the AGF. Simulation results show that the AGF rotation errors are crucial factors affecting the profile error of the machined workpiece. Experimental results show that employing the compensation algorithm increases machining accuracy. [ABSTRACT FROM AUTHOR]

Polycystic ovary syndrome (PCOS) is a common metabolic disorder in women. To identify causative genes, we conducted a genome-wide association study (GWAS) of PCOS in Han Chinese. The discovery set included 744 PCOS cases and 895 controls; subsequent replications involved two independent cohorts (2,840 PCOS cases and 5,012 controls from northern Han Chinese; 498 cases and 780 controls from southern and central Han Chinese). We identified strong evidence of associations between PCOS and three loci: 2p16.3 (rs13405728; combined P-value by meta-analysis Pmeta = 7.55 × 10−21, odds ratio (OR) 0.71); 2p21 (rs13429458, Pmeta = 1.73 × 10−23, OR 0.67); and 9q33.3 (rs2479106, Pmeta = 8.12 × 10−19, OR 1.34). These findings provide new insight into the pathogenesis of PCOS. Follow-up studies of the candidate genes in these regions are recommended. [ABSTRACT FROM AUTHOR]

Tobacco hornworm, Manduca sexta, is a model insect for studying the action of Bacillus thuringiensis (Bt) Cry toxins on lepidopterans. The proteins, which bind Bt toxins to midgut epithelial cells, are key factors involved in the insecticidal functions of the toxins. Three Cry1A-binding proteins, viz., aminopeptidase N (APN), the cadherin-like Bt-R1, and membrane-type alkaline phosphatase (m-ALP), were localized, by immunohistochemistry, in sections from the anterior, middle, and posterior regions of the midgut from second instar M. sexta larvae. Both APN and m-ALP were distributed predominantly along microvilli in the posterior region and to a lesser extent on the apical tip of microvilli in the anterior and middle regions. Bt-R1 was localized at the base of microvilli in the anterior region, over the entire microvilli in the middle region, and at both the apex and base of microvilli in the posterior region. The localization of rhodamine-labeled Cry1Aa, Cry1Ab, and Cry1Ac binding was determined on sections from the same midgut regions. Cry1Aa and Cry1Ab bound to the apical tip of microvilli almost equally in all midgut regions. Binding of Cry1Ac was much stronger in the posterior region than in the anterior and middle regions. Thus, binding sites for Bt proteins and Cry1A toxins are co-localized on the microvilli of M. sexta midgut epithelial cells. [ABSTRACT FROM AUTHOR]

In this study, the sliding grid method is used to simulate a 350 km/h high-speed train passing through a 350 m standard single-line tunnel. The cross-sectional pressure distribution ahead of the train is investigated, the three-dimensional characteristics and propagation mechanism of pressure waves are described based on iso-pressure surfaces, and a newly accurate pressure sensor layout is proposed. The results show that the farther the cross-section is from the train, the smaller the cross-sectional pressure difference is. Influenced by the shape of the train nose and tunnel cross-section, the pressure waves are not simple planar waves, but spherical waves that vary in complexity over the propagation process. As the pressure difference of the 16.6 m cross-section before the train is within 1 Pa, the pressure waves behind this cross-section are defined as planar waves. Besides, the pressure peak-to-peak value difference between the wall and construction clearance reaches 13% at 70–90 m cross-sections, so the pressure sensors should be placed on the surface of the appurtenances rather than on the tunnel wall. In summary, this study is significant for understanding the formation and transmission mechanisms of pressure waves and guiding the scientific layout of pressure sensors in tunnels. [ABSTRACT FROM AUTHOR]

Time-variant reliability analysis plays a vital role in improving the validity and practicability of product reliability evaluation over a specific time interval. Sampling-based extreme value method is the most direct way to implement accurate reliability assessment. Its adoption for time-variant reliability analysis, however, is limited due to the computational burden caused by repeatedly evaluating performance function. This paper proposes a semi-analytical extreme value method to improve the computational efficiency of extreme value method. The time-variant performance function is transformed into dependent instantaneous performance functions in which the stochastic processes are discretized by the expansion optimal linear estimation method to simulate the dependence among different time instants. Each instantaneous function is separately approximated by Taylor series expansion at the most probable point through instantaneous reliability analysis. Based on the approximated performance functions, the computational cost of sampling-based extreme value method is significantly reduced. Results of three numerical examples demonstrate the efficacy of the proposed method. [ABSTRACT FROM AUTHOR]

The Periodontal Ligament (PDL) plays a very important role in load transmission between the teeth and alveolar bone. To capture biomechanical responses of Orthodontics, numerical analysis need to consider multiple types of materials: incompressible visco-hyperelastic for the PDL and compressible elastic for teeth. This article proposes a unified-implementation of smoothed finite element methods (UI-SFEM), which enables the use of different types of smoothing domains for different materials. It has several important properties: (1) A UI-SFEM model can use any types of smoothing domains in a combination as desired for complex systems. (2) The choice of the smoothing domain types can be done in a single model based on the user needs (material properties, incompressible numerical problems). (3) It provides a framework for designing models with different solution properties. Numerical experiments show that the UI-SFEM is efficient and robust against mesh distortion, which is works particularity well for complex biological systems. [ABSTRACT FROM AUTHOR]

Highlights: Mechanisms underlying immunosuppressive tumor immune microenvironment (TIME) in ‘cold’ tumor are summarized. Recent nanotechnology-based strategies for ‘cold’ TIME firing up are emphasized. Challenges and perspectives of nanomedicines for ‘cold’ tumor treatment are proposed.Although current anticancer immunotherapies using immune checkpoint inhibitors (ICIs) have been reported with a high clinical success rate, numerous patients still bear ‘cold’ tumors with insufficient T cell infiltration and low immunogenicity, responding poorly to ICI therapy. Considering the advancements in precision medicine, in-depth mechanism studies on the tumor immune microenvironment (TIME) among cold tumors are required to improve the treatment for these patients. Nanomedicine has emerged as a promising drug delivery system in anticancer immunotherapy, activates immune function, modulates the TIME, and has been applied in combination with other anticancer therapeutic strategies. This review initially summarizes the mechanisms underlying immunosuppressive TIME in cold tumors and addresses the recent advancements in nanotechnology for cold TIME reversal-based therapies, as well as a brief talk about the feasibility of clinical translation. [ABSTRACT FROM AUTHOR]

Angiogenesis is essential in tumor biology and is regulated by vascular endothelial growth factor (VEGF) ligands and receptors. Here we aimed to discover genetic variants associated with levels of circulating angiogenic proteins in cancer patients. Plasma was collected at baseline in 216 pancreatic and 114 colorectal cancer patients. Thirty-one angiogenic proteins were measured by ELISA. 484,523 Single Nucleotide Polymorphisms (SNP) were tested for association with plasma levels for each protein in pancreatic cancer patients. Three top-ranked hits were then genotyped in colorectal cancer patients, where associations with the same proteins were measured. The results demonstrated rs2284284 and MCP1 (P-value = 6.7e-08), rs7504372 and VEGF-C (P-value = 9.8e-09), and rs7767396 and VEGF-A (P-value = 5.8e-09) were SNP-protein pairs identified in pancreatic cancer patients. In colorectal cancer patients, only rs7767396 (A > G) and VEGF-A was validated (P-value = 5.18e-05). The AA genotype of rs7767396 exhibited 2.04-2.3 and 2.7-3.4-fold higher VEGF-A levels than those with AG and GG genotypes. The G allele of rs7767396 reduces binding of the NF-AT1 transcription factor. In conclusion, a common genetic variant predicts the plasma levels of VEGF-A in cancer patients through altered binding of NF-AT1. [ABSTRACT FROM AUTHOR]

Objectives: This study was designed to determine the optimal anterior-posterior (AP) position of upper incisors through Anterior Nasal Spine (ANS) point. Materials and methods: Lateral cephalometric radiographic images of 690 patients were collected and divided into a derivation group and a validation group, and the former were subdivided into a proper AP position (PAP) group and an improper AP position (iPAP) group. The distance from facia-axis (FA) point of upper incisors to the line perpendicular to Frankfort horizontal (FH) plane through ANS (FA-ANS) was measured, and the relationship between FA-ANS and several cephalometric indices were studied through Pearson correlation analysis. Receiver operating characteristic (ROC) curves for different clinical indices were analyzed to evaluate the diagnostic efficiency of optimal AP position of upper incisors. Results: The average value of FA-ANS in PAP group was 0.57±1.99, which was significantly different from FA-ANS in iPAP group. Cephalometric indices such as U1-NA, U1-SN, AB-NPo, UL-TVL, Wits, and ANB were found to be correlated with FA-ANS. The receiver operating characteristic (ROC) curves represented a greater diagnostic efficiency of FA-ANS compared with other clinical indices. Conclusions: ANS point, as a stable skeletal landmark, could be used to access an optimal AP position of upper incisors, providing aids to clinical diagnosis and treatment goal determination for clinical practice. Clinical relevance: A new index FA-ANS, together with other traditional indices, could help determine the optimal position of upper incisors and provide a personalized therapeutic plan. [ABSTRACT FROM AUTHOR]

An effective method for reliability-based design optimization (RBDO) problems taking uncertainties into account is the probabilistic feasible region (PFR) approach. The PFR approach is built around the fixed nature of the standard deviation in general RBDO problems. Therefore, the accuracy of the PFR approach will be affected when dealing with RBDO problems with varying standard deviation. To improve the accuracy of PFR method in solving the RBDO problems with varying standard deviation, a novel probabilistic feasible region strategy considering varying standard deviations (PFR-vstd) approach is suggested in this paper. In place of the initial probabilistic feasible region in standard normal space, a new probabilistic feasible region is established in original design space in this novel approach. The results of four applications demonstrate the high accuracy and sufficient efficiency of PFR-vstd method. The findings demonstrate that PFR-vstd method is capable of accurately resolving RBDO problems with varying standard deviation. [ABSTRACT FROM AUTHOR]

A new mathematical model, optical-power-dependent model R(P), is proposed by investigating the nonlinearity of modified uni-traveling carrier photodiodes (MUTC-PD). Benefiting from this model, the harmonic power and output 3rd order intercept point (OIP3) of a photodiode can be calculated. Considering a bias voltage shift of the photodiode caused by a large voltage swing effect, the R(P) mathematical model is expanded into a voltage-related one, which is the optical-power-and-voltage-dependent model, R(P,V). The calculate results of both mathematical models are completely in accord with simulation results. [ABSTRACT FROM AUTHOR]

In this paper, a new single-loop active learning Kriging method with probability of rejecting classification is proposed for solving time-dependent system reliability analysis problems. The proposed method aims at making full use of the response information of all potential failure time instants or failure modes to improve the sampling efficiency and algorithm interpretability. Firstly, the probability of rejecting classification of each candidate sample for single failure mode is derived based on the Kriging models that are used to approximate the performance functions. Then, both the joint probability of rejecting classification and cumulative probability of rejecting classification are constructed for time-dependent series system and time-dependent parallel system, respectively. Any potential failure information for multiple failure modes over the entire time interval is taken into account. On this basis, an effective active learning strategy is developed to identify the new training sample and the target Kriging model to be updated corresponding to a certain failure mode. The maximum real-time estimation error criterion for time-dependent system problem is utilized to stop refining Kriging models after fully exploiting the limit state surface. Finally, three examples are used to demonstrate the excellent efficiency and computational accuracy of the proposed method. [ABSTRACT FROM AUTHOR]

Critical properties of TBCs include low thermal conductivity (TC) and high cyclic durability. In recent years, the solution precursor plasma spray (SPPS) process has been effectively used for deposition of TBCs with enhanced cyclic durability for yttria-stabilized zirconia (YSZ) and the higher temperature yttrium aluminum garnet (YAG) TBCs. Improvements in deposition efficiency (DE) and deposition rate (DR) were identified as needed for cost-effective commercialization. In this work, SPPS YAG TBCs with low TC and high DE and DR have been produced with microstructures containing a high density of planar arrays of increased porosity called inter-pass boundaries (IPBs). The IPBs have been shown to reduce the TC of SPPS YAG TBCs by 39% to a value of 0.58 W/mK at 1300 °C. Increasing the precursor feed rates and decreasing the raster scan step heights generate high-density IPB microstructures, while simultaneously increasing the DE and DR by 53 and 190%, respectively. The SPPS YAG microstructures with high-density IPBs also exhibit improved thermal cycling and sinter resistance compared to APS YSZ. [ABSTRACT FROM AUTHOR]

Surrogate models are usually used as a time-saving approach to reduce the computational burden of expensive computer simulations for engineering design. However, it is difficult to choose an appropriate model for an unknown design space. To tackle this problem, an effective method is forming an ensemble model that combines several surrogate models. Many efforts were made to determine the weight factors of ensemble, which include global and local measures. This article investigates the characteristics of global and local measures, and presents a new ensemble model which combines the advantages of these two measures. In the proposed method, the design space is divided into two parts, and different strategies are introduced to evaluate the weight factors in these two parts respectively. The results from numerical and engineering design cases show that the proposed ensemble model has satisfactory robustness and accuracy (it performs best for most cases tested in this article), while spending almost the equivalent modeling time (the additional cost is not more than 6.7% for any case tested in this article) compared with the combined global and local ensemble models. [ABSTRACT FROM AUTHOR]

Sample data may be corrupted by noise in engineering problems. In order to make satisfactory approximations for the data with noise, some regression metamodels are adopted in current researches. The commonly used nugget-effect Kriging regards the variance of noise as a constant and ignores the difference of the noise influence, thus may not be effective enough in some cases. Therefore, a Kriging-based metamodel which combines the merits of Kriging and Support Vector Regression (SVR) is put forward for improving the performance in metamodeling with noisy data. The developed method, termed as SVEK, can capture the underlying trend of an unknown function efficiently by classifying the sample points and then regressing these classified points with different extents. Besides, a criterion for selecting the error margin ε in SVR training is proposed to facilitate the parameter setting process. Moreover, a one-variable test example is used to illustrate the modeling theory and construction procedures of SVEK. Eight numerical benchmark problems with different important characteristics are used to validate the proposed method. Then an overall comparison between the nugget-effect Kriging and the proposed method has been made. Results show that SVEK is promising in metamodeling with noisy data. [ABSTRACT FROM AUTHOR]

Time-variant reliability-based design optimization (T-RBDO) issues are probabilistic design problems that assess the dependability of the design across time. The engineering situation is most closely resembled by it. The approaches to resolving T-RBDO problems, nevertheless, are convoluted and time-consuming. In this paper, an effective strategy for solving RBDO issues are extended to resolving TRBDO problems in order to increase efficiency. To solve T-RBDO challenges, the time-variant probabilistic feasible region (T-PFR) approach, which is based on the PFR method for resolving RBDO issues, was presented. The idea of the equivalent inverse most probable point (EIMPP) is put out in this methodology. Based on the EIMPP, the probabilistic feasible region is likewise developed for time-variant constraints. The effective tactic of the proposed method is to identify the non-active time-variant constraints using the probabilistic feasible region and to forego conducting time reliability analysis on them. Three mathematics and two engineering issues demonstrate that the suggested solution is viable and effective. [ABSTRACT FROM AUTHOR]

The dielectric properties of Z-type hexaferrite Sr3Co2Fe24O41 (SCFO) have been investigated as a function of temperature from 153 to 503 K between 1 and 2 GHz. The dielectric responses of SCFO are found to be frequency dependent and thermally activated. The relaxation-type dielectric behavior is observed to be dominating in the low frequency region and resonance-type dielectric behavior is found to be dominating above 108 Hz. This frequency dependence of dielectric behavior is explained by the damped harmonic oscillator model with temperature dependent coefficients. The imaginary part of impedance (Z″) and modulus (M″) spectra show that there is a distribution of relaxation times. The scaling behaviors of Z″ and M″ spectra further suggest that the distribution of relaxation times is temperature independent at low frequencies. The dielectric loss spectra at different temperatures have not shown a scaling behavior above 108 Hz. A comparison between the Z″ and the M″ spectra indicates that the short-range charges motion dominates at low temperatures and the long-range charges motion dominates at high temperatures. The above results indicate that the dielectric dispersion mechanism in SCFO is temperature independent at low frequencies and temperature dependent at high frequencies due to the domination of resonance behavior. [ABSTRACT FROM AUTHOR]

The ability to survive hypoxic conditions is important for various organisms, especially for aquatic animals. Teleost fish, representing more than 50 % of vertebrate species, are extremely efficient in utilizing low levels of dissolved oxygen in water. However, huge variations exist among various taxa of fish in their ability to tolerate hypoxia. In aquaculture, hypoxia tolerance is among the most important traits because hypoxia can cause major economic losses. Genetic enhancement for hypoxia tolerance in catfish is of great interest, but little was done with analysis of the genetic architecture of hypoxia tolerance. The objective of this study was to conduct a genome-wide association study to identify QTLs for hypoxia tolerance using the catfish 250K SNP array with channel catfish families from six strains. Multiple significant and suggestive QTLs were identified across and within strains. One significant QTL and four suggestive QTLs were identified across strains. Six significant QTLs and many suggestive QTLs were identified within strains. There were rare overlaps among the QTLs identified within the six strains, suggesting a complex genetic architecture of hypoxia tolerance. Overall, within-strain QTLs explained larger proportion of phenotypic variation than across-strain QTLs. Many of genes within these identified QTLs have known functions for regulation of oxygen metabolism and involvement in hypoxia responses. Pathway analysis indicated that most of these genes were involved in MAPK or PI3K/AKT/mTOR signaling pathways that were known to be important for hypoxia-mediated angiogenesis, cell proliferation, apoptosis and survival. [ABSTRACT FROM AUTHOR]

This study explores the viability and efficiency of employing a dual approach, combining proppant fracturing with acid fracturing, in ultra-low-permeability dolomite reservoirs. The damage of guar gum fracturing fluid and slick water fracturing fluid on rock permeability was assessed through high-pressure pulse permeability testing. The mechanical properties of rocks post-acid treatment were evaluated using gelled acid, and fracture conductivity under various stimulation methods was measured. The results reveal that both guar gum and slick water fracturing fluids induce minimal damage to reservoir permeability. Following 10 and 30 min of acid treatment, the Young's modulus of the rocks is decreased by 10.65% and 17.63%, respectively, enhancing the effectiveness of hydraulic fracturing. As closure pressure increases, the conductivity of acid-etched self-propped fractures decreases rapidly due to the highly non-uniform etching caused by the acid. The addition of proppants markedly enhances the conductivity retention of fractures. The particle size of proppants exerts a significant influence on fracture conductivity, with larger proppant sizes leading to enhanced conductivity. However, as closure stress escalates, the disparity in conductivity between fractures with varying proppant sizes diminishes. Fracture conductivity tests conducted under various stimulation methods reveal that introducing proppants before acid treatment yields the highest fracture conductivity. Delayed addition of acid prevents proppants from occupying the acid-etched channels, thus enhancing reservoir treatment effectiveness. This study holds significant importance for designing effective stimulation techniques tailored to ultra-low-permeability dolomite reservoirs. [ABSTRACT FROM AUTHOR]

Background: Hypertension and proteinuria are common bevacizumab-induced toxicities. No validated biomarkers are available for identifying patients at risk of these toxicities.Methods: A genome-wide association study (GWAS) meta-analysis was performed in 1039 bevacizumab-treated patients of European ancestry in four clinical trials (CALGB 40502, 40503, 80303, 90401). Grade ≥2 hypertension and proteinuria were recorded (CTCAE v.3.0). Single-nucleotide polymorphism (SNP)-toxicity associations were determined using a cause-specific Cox model adjusting for age and sex.Results: The most significant SNP associated with hypertension with concordant effect in three out of the four studies (p-value <0.05 for each study) was rs6770663 (A > G) in KCNAB1, with the G allele increasing the risk of hypertension (p-value = 4.16 × 10-6). The effect of the G allele was replicated in ECOG-ACRIN E5103 in 582 patients (p-value = 0.005). The meta-analysis of all five studies for rs6770663 led to p-value = 7.73 × 10-8, close to genome-wide significance. The most significant SNP associated with proteinuria was rs339947 (C > A, between DNAH5 and TRIO), with the A allele increasing the risk of proteinuria (p-value = 1.58 × 10-7).Conclusions: The results from the largest study of bevacizumab toxicity provide new markers of drug safety for further evaluations. SNP in KCNAB1 validated in an independent dataset provides evidence toward its clinical applicability to predict bevacizumab-induced hypertension. ClinicalTrials.gov Identifier: NCT00785291 (CALGB 40502); NCT00601900 (CALGB 40503); NCT00088894 (CALGB 80303) and NCT00110214 (CALGB 90401). [ABSTRACT FROM AUTHOR]

Shikonin is the main component of the traditional Chinese medicine comfrey, which can inhibit the activity of PKM2 by regulating glycolysis and ATP production. Rheumatoid arthritis synovial cells (RA-FLSs) have been reported to increase glycolytic activity and have other similar hallmarks of metabolic activity. In this study, we investigated the effects of shikonin on glycolysis, mitochondrial function, and cell death in RA-FLSs. The results showed that shikonin induced apoptosis and autophagy in RA-FLSs by activating the production of reactive oxygen species (ROS) and inhibiting intracellular ATP levels, glycolysis-related proteins, and the PI3K-AKT-mTOR signaling pathway. Shikonin can significantly reduce the expression of apoptosis-related proteins, paw swelling in rat arthritic tissues, and the levels of inflammatory factors in peripheral blood, such as TNF-α, IL-6, IL-8, IL-10, IL-17A, and IL-1β while showing less toxicity to the liver and kidney. [ABSTRACT FROM AUTHOR]

Purpose: Inulin is a type of fermentable dietary fiber, which is non-digestible, and can improve metabolic function by modulating intestinal microbiota. This study aimed to evaluate the role of inulin in hyperuricemia and microbial composition of the gut microbiota in a mouse model of hyperuricemia established through knockout of Uox (urate oxidase) gene. Methods: KO (Uox -knockout) and WT (wild-type) mice were given inulin or saline by gavage for 7 weeks. The effect of inulin to combat hyperuricemia was determined by assessing the changes in serum UA (uric acid) levels, inflammatory parameters, epithelial barrier integrity, fecal microbiota alterations, and SCFA (short-chain fatty acid) concentrations in KO mice. Results: Inulin supplementation can effectively alleviate hyperuricemia, increase the expressions of ABCG2 in intestine, and downregulate expression and activity of hepatic XOD (xanthine oxidase) in KO mice. It was revealed that the levels of inflammatory cytokines and the LPS (lipopolysaccharide) were remarkably higher in the KO group than those in the WT group, indicating systemic inflammation of hyperuricemic mice, but inulin treatment ameliorated inflammation in KO mice. Besides, inulin treatment repaired the intestinal epithelial barrier as evidenced by increased levels of intestinal TJ (tight junction) proteins [ZO-1 (zonula occludens-1) and occluding] in KO mice. Moreover, serum levels of uremic toxins, including IS (indoxyl sulfate) and PCS (p -cresol sulfate), were reduced in inulin-treated KO mice. Further investigation unveiled that inulin supplementation enhanced microbial diversity and raised the relative abundance of beneficial bacteria, involving SCFAs-producing bacteria (e.g., Akkermansia and Ruminococcus). Additionally, inulin treatment increased the production of gut microbiota-derived SCFAs (acetate, propionate and butyrate concentrations) in KO mice, which was positively correlated with the effectiveness of hyperuricemia relief. Conclusions: Our findings showed that inulin may be a promising therapeutic candidate for the treatment of hyperuricemia. Moreover, alleviation of hyperuricemia by inulin supplementation was, at least, partially conciliated by modulation of gut microbiota and its metabolites. [ABSTRACT FROM AUTHOR]

Pancreatic cancer is a highly aggressive malignancy characterized by poor survival, recurrence after surgery and resistance to therapy. Nerves infiltrate the microenvironment of pancreatic cancers and contribute to tumor progression, however the clinicopathological significance of tumor innervation is unclear. In this study, the presence of nerves and their cross-sectional size were quantified by immunohistochemistry for the neuronal markers S-100, PGP9.5 and GAP-43 in a series of 99 pancreatic cancer cases versus 71 normal adjacent pancreatic tissues. A trend was observed between the presence of nerves in the tumor microenvironment of pancreatic cancer and worse overall patient survival (HR = 1.8, 95% CI 0.77–4.28, p = 0.08). The size of nerves, as measured by cross-sectional area, were significantly higher in pancreatic cancer than in the normal adjacent tissue (p = 0.002) and larger nerves were directly associated with worse patient survival (HR = 0.41, 95% CI 0.19–0.87, p = 0.04). In conclusion, this study suggests that the presence and size of nerves within the pancreatic cancer microenvironment are associated with tumor aggressiveness. [ABSTRACT FROM AUTHOR]

Upper ocean responses to the passage of sequential tropical cyclones over the northwestern South China Sea (SCS) in 2011 were investigated using satellite remote sensing data, Argo reanalysis data, and an array of mooring data. We found that the sea surface low temperature region lasted for more than 38 days and two phytoplankton blooms occurred after the passage of sequential tropical cyclones. The upper ocean cooling reached 2–5°C with a right-side bias was observed along the typhoon track to about 200 km. The maintenance of low temperature region and the two phytoplankton blooms were mainly driven by upwelling and near-inertial turbulence mixing induced by the sequential tropical cyclones. The first phytoplankton bloom appeared on the 7th day after the passage of the three tropical cyclones, and the chlorophyll a (chl a) concentration increased by 226%, which may be mainly driven by typhoons induced upwelling. The second phytoplankton bloom occurred on the 30th day, the chl-a concentration increased by 290%. Further analysis suggested that only the typhoons with similar characteristics as Nesat and Nalgae can induce strong near-inertial oscillation (NIO). Strong turbulent mixing associated with the near-inertial baroclinic shear instability lasted for 26 days. The measured mean eddy diffusivity in the upper ocean was above 10−4 m2/s after typhoon Nesat. Enhancement of the turbulent mixing in the upper ocean helped to transport nutrient-rich cold waters from the deep layer to the euphotic layer, and is a major mechanism for the long-term maintenance of low temperature region as well as the second phytoplankton bloom. [ABSTRACT FROM AUTHOR]

Reliability-based design optimization (RBDO) is powerful for probabilistic constraint problems. Metamodeling is usually used in RBDO to reduce the computational cost. Kriging model-based RBDO is very suitable to solve engineering problems with implicit constraint functions. However, the efficiency and accuracy of the kriging model constrain its use in RBDO. In this research, the importance boundary sampling (IBS) method is enhanced by the probability feasible region (PFR) method to fit kriging model with high accuracy. The proposed probability feasible region enhanced importance boundary sampling (PFRE-IBS) method selects sample points for inactive constraint functions only in its important region, thus reducing the number of sample points to improve the efficiency of sampling method. In order to verify the efficiency and accuracy of the proposed PFRE-IBS method, three RBDO problems are used in this paper. The comparison results with other sampling methods show that the proposed PFRE-IBS method is very efficient and accurate. [ABSTRACT FROM AUTHOR]