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AbstractIt is of importance to investigate the significance of a subset of covariates W for the response Y given covariates Z in regression modeling. To this end, we propose a significance test for the partial mean independence problem based on machine learning methods and data splitting. The test statistic converges to the standard chi-squared distribution under the null hypothesis while it converges to a normal distribution under the fixed alternative hypothesis. Power enhancement and algorithm stability are also discussed. If the null hypothesis is rejected, we propose a partial Generalized Measure of Correlation (pGMC) to measure the partial mean dependence of Y given W after controlling for the nonlinear effect of Z. We present the appealing theoretical properties of the pGMC and establish the asymptotic normality of its estimator with the optimal root-N convergence rate. Furthermore, the valid confidence interval for the pGMC is also derived. As an important special case when there are no conditional covariates Z, we introduce a new test of overall significance of covariates for the response in a model-free setting. Numerical studies and real data analysis are also conducted to compare with existing approaches and to demonstrate the validity and flexibility of our proposed procedures. [ABSTRACT FROM AUTHOR]

A discrete-continuous (PFC–FLAC) coupling method was used in this study to simulate laboratory triaxial tests with soybean granular material. The mesoscopic mechanical parameters of the soybean granular material were calibrated by comparing them with actual laboratory test results, and the validity of the modeling method was verified. Subsequently, the particle motion law and mechanical mechanism of the soybean granular materials were analyzed based on the particle displacement field, velocity field, and force chain network. The results showed that the coupled PFC–FLAC method could better describe the macroscopic stress–strain relationship, deformation damage characteristics, and shear strength mechanical indexes of soybean granular materials. With increasing confining pressure (50–200 kPa), the bulging deformation of the specimens changed from uniform to concentrated but uneven. The particle contact number and maximum particle contact stress increased by 19.3 and 48%, respectively. Additionally, variations of the macroscopic properties of the specimens with microscopic parameters were revealed. Under the same conditions, the change in the peak stress of the specimen was proportional to the interparticle friction coefficient. Moreover, the slope of the stress–strain curve increased gradually with an increase in the effective modulus. [ABSTRACT FROM AUTHOR]

AbstractThis article aims to develop an effective model-free inference procedure for high-dimensional data. We first reformulate the hypothesis testing problem via sufficient dimension reduction framework. With the aid of new reformulation, we propose a new test statistic and show that its asymptotic distribution is χ2 distribution whose degree of freedom does not depend on the unknown population distribution. We further conduct power analysis under local alternative hypotheses. In addition, we study how to control the false discovery rate of the proposed χ2 tests, which are correlated, to identify important predictors under a model-free framework. To this end, we propose a multiple testing procedure and establish its theoretical guarantees. Monte Carlo simulation studies are conducted to assess the performance of the proposed tests and an empirical analysis of a real-world dataset is used to illustrate the proposed methodology. Supplementary materials for this article are available online including a standardized description of the materials available for reproducing the work. [ABSTRACT FROM AUTHOR]

Hard thresholding rule is commonly adopted in feature screening procedures to screen out unimportant predictors for ultrahigh-dimensional data. However, different thresholds are required to adapt to different contexts of screening problems and an appropriate thresholding magnitude usually varies from the model and error distribution. With an ad-hoc choice, it is unclear whether all of the important predictors are selected or not, and it is very likely that the procedures would include many unimportant features. We introduce a data-adaptive threshold selection procedure with error rate control, which is applicable to most kinds of popular screening methods. The key idea is to apply the sample-splitting strategy to construct a series of statistics with marginal symmetry property and then to utilize the symmetry for obtaining an approximation to the number of false discoveries. We show that the proposed method is able to asymptotically control the false discovery rate and per family error rate under certain conditions and still retains all of the important predictors. Three important examples are presented to illustrate the merits of the new proposed procedures. Numerical experiments indicate that the proposed methodology works well for many existing screening methods. for this article are available online. [ABSTRACT FROM AUTHOR]

We develop a new class of distribution-free multiple testing rules for false discovery rate (FDR) control under general dependence. A key element in our proposal is a symmetrized data aggregation (SDA) approach to incorporating the dependence structure via sample splitting, data screening, and information pooling. The proposed SDA filter first constructs a sequence of ranking statistics that fulfill global symmetry properties, and then chooses a data-driven threshold along the ranking to control the FDR. The SDA filter substantially outperforms the Knockoff method in power under moderate to strong dependence, and is more robust than existing methods based on asymptotic p-values. We first develop finite-sample theories to provide an upper bound for the actual FDR under general dependence, and then establish the asymptotic validity of SDA for both the FDR and false discovery proportion control under mild regularity conditions. The procedure is implemented in the R package sdafilter. Numerical results confirm the effectiveness and robustness of SDA in FDR control and show that it achieves substantial power gain over existing methods in many settings. [ABSTRACT FROM AUTHOR]

This study makes a significant contribution to the field of groundwater potential mapping (GWPM) by exploring the application of ensemble learning models (ELMs), specifically boosting ensemble models (BEMs), which have not been fully utilized in GWPM. By employing six ELMs (random forest, AdaBoost, XGBoost, CatBoost, GBDT and LightGBM), along with Tree-structured Parzen Estimator in Luoning County, China, this study identifies key indicators (topographic position index, distance to rivers and topographic wetness index) and demonstrates the superior model performance of XGBoost compared to other ELMs. Additionally, correlation analysis confirms the accuracy of XGBoost in predicting relationships between important indicators and groundwater potentials. Finally, the findings provide valuable insights for sustainable groundwater management strategies in Luoning County and emphasize the need for further exploration of ELMs, development of comprehensive performance evaluation and indicator systems, reduction of the inconsistencies between indicators and predication results and practical research to support future sustainable groundwater management. [ABSTRACT FROM AUTHOR]

A meta-analysis was conducted to investigate the correlation between calcium intake and the risk of brain tumors (especially glioma). The PubMed, Web of Science, and Embase databases were searched for relevant papers on the association between calcium intake and glioma as of August 22, 2021. The odds ratio (OR) with a 95% confidence interval (CI) was calculated using a random-effects model. Egger's test was conducted to assess publication bias. The meta-analysis includes four studies. The meta-analysis showed that calcium intake and the risk of brain tumors have a significant negative relationship (OR = 0.28; 95% CI: 0.11 to 0.72; P = 0.008). Dose-response analysis showed that for every 100 mg/day increase in calcium intake, the risk of glioma decreased by 7% (OR = 0.93; 95% CI: 0.88 to 0.98). In addition, compared with humans without calcium intake, when calcium intake is 455 mg/day, 800 mg/day and 1000 mg/day, the risk of glioma is 0.65 (95% CI 0.43, 0.97), 0.55 (95% CI 0.37, 0.82) and 0.37 (95% CI 0.15, 0.86). There is a significant negative association between calcium intake and brain tumors (especially gliomas), but more high-quality studies are needed to verify these results. [ABSTRACT FROM AUTHOR]

With the advent of the Industry 4.0 era, the manufacturing industry realizes the importance of developing information and communications technology (ICT). Based on organizational information processing theory and resource-based view, this study constructs the conceptual model with the framework of "information-integration-performance," uses survey data from Chinese manufacturing enterprises, and investigates the impact of ICT alignment on supply chain performance using a structural equation model with supply chain integration as the mediation variable. The study found that ICT alignment has no direct effect on supply chain performance, but its indirect effect is significant under the mediation effect of supply chain integration. In the relationship between supply chain integration and financial performance, operational performance plays a good mediation effect. These findings help companies to implement Industry 4.0 and ICT strategies that apply ICT alignment rationally and innovatively to ensure good organizational operations and improve supply chain performance. [ABSTRACT FROM AUTHOR]

Childhood trauma tends to influence cortisol stress reactivity through the mediating effects of DNA methylation. Houtepen et al. conducted a study to investigate the role of DNA methylation in cortisol stress reactivity and its relationship with childhood trauma. The study collected a dataset consisting of 385,882 DNA methylation loci, cortisol stress reactivity, one-dimensional score on a childhood trauma questionnaire and several covariates for 85 healthy individuals. Of great scientific interest is to identify the active mediating loci out of the 385,882 ones. Houtepen et al. conducted 385,882 linear mediation analyses, in each of which one locus was considered, and identified three active mediating loci. More recently, van Kesteren and Oberski proposed a coordinate-wise mediation filter (CMF) and applied it to the same dataset. They identified five active mediating loci. Unfortunately, the three loci identified by Houtepen et al. are completely different from the five loci identified by van Kesteren and Oberski, probably because both Houtepen et al. and van Kesteren and Oberski did not consider all loci jointly in their analyses. The high dimensional DNA methylation loci indeed necessitate new techniques for identifying active mediating loci and testing the direct and indirect effects of the early life traumatic stress on later cortisol alteration. Motivated by the contradictory results in the aforementioned two scientific works, we develop a new estimating and testing procedure, and apply it to the same dataset as that analyzed by the two works. We identify three new loci: cg19230917, cg06422529 and cg03199124, and their effect sizes and p-values are 321.196 (p-value = 0.035965), 418.173 (p-value = 0.000234) and 471.865 (p-value = 0.001691), respectively. These three loci possess both reasonably neurobiological interpretations and statistically significant effects via our proposed tests. Based on our new procedure, we further confirm that the childhood trauma does not have significant direct effects on cortisol change—it only indirectly affects cortisol through DNA methylation, and the indirect effect is negative. for this article are available online. [ABSTRACT FROM AUTHOR]

In this paper, we provide a unified framework for two-sample t-test with partially paired data. We show that many existing two-sample t-tests with partially paired data can be viewed as special members in our unified framework. Some shortcomings of these t-tests are discussed. We also propose the asymptotically optimal weighted linear combination of the test statistics comparing all four paired and unpaired data sets. Simulation studies are used to illustrate the performance of our proposed asymptotically optimal weighted combinations of test statistics and compare with some existing methods. It is found that our proposed test statistic is generally more powerful. Three real data sets about CD4 count, DNA extraction concentrations, and the quality of sleep are also analyzed by using our newly introduced test statistic. [ABSTRACT FROM AUTHOR]

To explore the feasibility of high-intensity focused ultrasound (HIFU) ablation for treating metastatic pelvic tumors and recurrent ovary cancer. Eight patients with metastatic pelvic tumors or recurrent ovary cancer were enrolled in this study. Among them, 5 patients had ovarian cancer, 1 had cervical cancer, 1 had endometrial cancer, and 1 had rectal cancer. Six of them received abdominal surgical operation for their primary cancer, no one received radiotherapy. HIFU treatment was performed under conscious sedation. Vital signs were monitored during the procedure, and adverse effects were recorded. Postoperative follow-up was performed to observe pain relief and the improvement of the patient’s quality of life. The median age of the patients was 54 (range: 33–76) years, with a total of 12 lesions. The average volume of the lesions was 238.0 cm3. Six patients completed 12 months follow-up. Postoperative pain relief rate was 60% (3/5), and the quality of life improved in the short term. The main adverse effect of HIFU was pain in the treated area, with the pain score lower than 4, and all of which was self-relieved within 1 day after HIFU treatment. No serious complications such as skin burn, intestinal perforation, and nerve injury occurred. HIFU is feasible for the treatment of metastatic pelvic tumors or recurrent ovary cancer without serious complications. Therefore, HIFU seems a promising treatment for recurrent ovary cancer, metastatic pelvic tumors from cervical cancer, endometrial cancer, and rectal cancer. [ABSTRACT FROM AUTHOR]

A versatile dispersant plays a critical role in suspension stability of pesticide aqueous suspension concentrate (SC), thus it is extremely important to design and synthesize an effective dispersant for SC. Herein, nonionic trimeric nonylphenol polyoxyethylene (10) (TNP10) was successfully synthesized using nonylphenol polyoxyethylene(10) ethers (NP10) as raw materials. The surface activities of TNP10 were evaluated according to critical micelle concentration (CMC), and the surface tension at CMC (γCMC). TNP10 showed higher surface activity due to its lower CMC value compared with that of NP10. In addition, the dispersing and stabilizing properties of TNP10 in 25 wt.% pyraclostrobin SC system were investigated. The results showed that TNP10 as a dispersant exhibited more excellent dispersion performance than NP10. Meanwhile, the obtained SC system exhibits shear thinning behavior under high-speed shearing showing typical features of pseudo-plastic non-Newtonian fluids, which conforms to the Herschel-Buckley model. The nonionic trimeric nonylphenol polyoxyethylene (10 can effectively improve the surface activities and the suspension rate and stability of SC compared with its monomer NP10. [ABSTRACT FROM AUTHOR]

The Birnbaum–Saunders distribution is a widely used distribution in reliability applications to model failure times. For several samples from possible different Birnbaum–Saunders distributions, if their means can be considered as the same, it is of importance to make inference for the common mean. This paper presents procedures for interval estimation and hypothesis testing for the common mean of several Birnbaum–Saunders populations. The proposed approaches are hybrids between the generalized inference method and the large sample theory. Some simulation results are conducted to present the performance of the proposed approaches. The simulation results indicate that our proposed approaches perform well. Finally, the proposed approaches are applied to analyze a real example on the fatigue life of 6061-T6 aluminum coupons for illustration. [ABSTRACT FROM AUTHOR]

In the present work, we concentrate on the analytical study of American options under the CGMY process. The decomposition formula of the American option and the integral equation for the optimal-exercise boundary are established in explicit forms. Moreover, an analytical approximation formula is obtained for the American value. This approximation is valid when time to maturity is either very short or very long. Numerical simulations are provided for European options, optimal-exercise prices and approximate values for American options. [ABSTRACT FROM AUTHOR]

Five diarylpentanol derivatives including two new compounds stellerasme A (1), stellerasme B (2) were isolated from the aerial parts ofStelleropsis tianschanica. Their structures were elucidated by various spectroscopic techniques (UV, IR, MS, CD, 1D and 2D NMR). All compounds were evaluated for their cytotoxicity activity against HeLa and KB cell lines, and compound1showed selective activities against HeLa cell line with an IC50value of 7.4 μM. [ABSTRACT FROM PUBLISHER]

Two new stigmastane type of steroidal glycosides, vernoniacums A and B (1 and 2), with a Δ7,9(11) steroidal core were isolated from the roots of Vernonia cumingiana. Their structures were elucidated based on various spectroscopic techniques, including IR, HR-FAB-MS, and 1D and 2D NMR. Both compounds were evaluated for their cytotoxicity against HeLa and HCT-8 cells, and compound 1 showed mild activity against the tested cell lines with IC50 values of 15.8 and 35.7 pounds were evaluated for their cytotoxicity against HeLa and HCT-8 cells, and compound 1 showed mild activity against the tested cell lines with IC50 values of 15.8 and 35.7 µM, respectively. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the empirical-likelihood-based inference for the construction of confidence intervals and regions of the parameters of interest in single index models with missing covariates at random. An augmented inverse probability weighted-type empirical likelihood ratio for the parameters of interest is defined such that this ratio is asymptotically standard chi-squared. Our approach is to directly calibrate the empirical log-likelihood ratio, and does not need multiplication by an adjustment factor for the original ratio. Our bias-corrected empirical likelihood is self-scale invariant and no plug-in estimator for the limiting variance is needed. Some simulation studies are carried out to assess the performance of our proposed method. [ABSTRACT FROM AUTHOR]

In the paper, the authors establish some new Hermite-Hadamard type inequalities for differentiable co-ordinated convex functions of two variables. [ABSTRACT FROM AUTHOR]

Birnbaum–Saunders (BS) distribution is widely used in reliability applications to model failure times. For several samples from possible different BS distributions, to prevent wrong conclusions in any further analysis, it is of importance to accompany a formal comparison for characteristic quantities of the distributions, including mean, quantile and reliability function difference. To this end, two test statistics, which are respectively based on the exact generalizedp-value approach and the Delta method, are proposed and their behaviours are investigated. Simulation studies are carried out to examine the size and power performance of the newly proposed statistics. An interesting phenomenon is that in the finite sample simulations we conduct, the Delta method-based test almost uniformly outperforms the generalizedp-value-based test although its sampling null distribution is simulated by Monte Carlo method. This might suggest that the sampling null distribution of the Delta method-based test statistic would have a fast convergence to its limit. The tests are also applied to analyse a real example on the fatigue life of 6061-T6 aluminium coupons for illustration. [ABSTRACT FROM AUTHOR]

One of the most basic and important problems in statistical inference is the construction of the confidence interval (CI). In this paper, we propose a novel CI for a binomial proportion by modifying the midpoint of the score interval. The proposed modified interval can solve the ‘downward spikes’ problem of the score interval without enlarging the interval length. Simulation studies are carried out to illustrate the performance of the modified interval. With regard to the criterions of coverage probability, mean absolute error and expected length, our method is competitive among the several commonly used methods for constructing a CI. A real data example is also presented to show the application of our method. [ABSTRACT FROM AUTHOR]

Cassane-type diterpenes are main bioactive constituents of Caesalpinia minax HANCE. As a part of our ongoing chemical investigation of C. minax, two new degradative cassane-type diterpenes, named caesalpins I (1) and J (2), were isolated from the EtOAc extract of the seeds of C. minax. The structures were elucidated by means of spectroscopic analysis. [ABSTRACT FROM AUTHOR]

Two new cassane-type diterpenes, neocaesalpin MR (1) and minaxin C (2), were isolated from Caesalpinia minax HANCE. The structures of these compounds were elucidated by means of spectroscopic analysis. Among these isolated compounds, neocaesalpin MR showed mild activities toward HeLa and colon cancer (HCT-8) human cancer cell lines. [ABSTRACT FROM PUBLISHER]

Conclusions: The long-term quality of life of adolescents with chronic rhinosinusitis improved significantly after functional endoscopic sinus surgery (FESS), and endoscopic sinus surgery showed certain benefits for adolescent patients. The selection of appropriate patients may further improve the surgical outcomes and quality of life. Objective: To analyze the long-term quality of life in adolescents (12-18 years) with chronic rhinosinusitis after endoscopic sinus surgery, and to evaluate the value of endoscopic sinus surgery in adolescent patients. Methods: From 2003 to 2008, 729 adolescents with chronic sinusitis underwent endoscopic sinus surgery in our department; 270 of these patients were included in the study. Their quality of life was assessed before and within 3-8 years after the surgery using the SNOT-20 scale and was compared with that of healthy individuals of the same age. Results: The SNOT-20-based assessment showed that the overall quality of life differed significantly before and after surgery ( p = 0.000) and that some symptoms (dizziness, sense of facial oppression, sleep difficulty, embarrassment, and fatigue) had no significant differences before and after surgery ( p > 0.05). Preoperative and postoperative symptoms (dizziness, sense of facial oppression, sleep difficulty, embarrassment, and fatigue) showed no significant differences between the healthy population and treated patients ( p > 0.05). [ABSTRACT FROM AUTHOR]

In this study, we consider the testing problem about the null hypothesis that the nonlinear part in the partial linear regression model with missing response at random is a parametric function or not against the alternative that it is nonparametric. By imputation and inverse probability weighting methods, we then construct two completed data sets. Two empirical process-based tests, from these completed data sets, are introduced. Under the null hypothesis and local alterative hypotheses, the limiting null distributions and power study of the test statistics are, respectively, investigated. A nonparametric Monte Carlo test procedure, which can automatically make the test procedure scale-invariant even when the test statistics are not scale-invariant, is applied to approximate the limiting null distributions of the test statistics. Simulation study is carried out to examine the performance of the tests. We illustrate the proposed method with a real data set on monozygotic twins. [ABSTRACT FROM PUBLISHER]

A dinuclear copper(II) complex [Cu2(oxheel)] was synthesized and its structure was analyzed. This compound was then mixed with a surfactant (Brij35 or LSS) to form a metallomicelle, which would catalyze the phenol oxidation with the hydrogen peroxide (H2O2). The reaction mechanism and the mathematic model for the kinetics of this reaction were proposed, and the effect of the molar ratio between H2O2 and catalyst, of the temperature and of the pH levels on the rate of catalytic reaction were studied. [ABSTRACT FROM AUTHOR]

AbstractIn order to protect and develop marine resources, it is essential to reinforce the calcareous sand foundation on coral reefs during engineering construction. This study proposes a novel approach that combines enzyme-induced carbonate precipitation (EICP) with casein to solidify calcareous sand, which overcomes the issues of low calcium carbonate crystallization and insufficient cementation strength encountered in the pure EICP method. This study investigated the reinforcement effects and mechanisms of the combined method across various scales. Sonic time testing revealed an initial decline in sample density followed by a gradual increase, with the lowest density observed at 10% casein content. Sample strength depends on casein dosage and curing time. Overall, the trend in sample strength showed an initial decrease followed by a gradual increase, with 10% casein content again resulting in the lowest strength. The measured experimental groups achieved a minimum strength of approximately 1.17 MPa and a maximum strength of around 6.34 MPa. As casein concentration rises, the optimal curing time increases from 12–48 h. Microscopic experiments reveal casein expansion and dissolution in the EICP liquid, explaining UCS value changes with casein dosage and curing time. Combining scanning electron microscopy and microscopic experiments highlights the cementitious material’s vital role in strengthening samples. In conclusion, combining EICP and casein for solidifying calcareous sand is technically feasible and highly effective with significant reinforcement effects. [ABSTRACT FROM AUTHOR]

Amino acid functionalized D301 resins (Tyr-D301, Phe-D301, and Ala-D301) are successfully prepared to remove phenols. The influences of adsorption condition on adsorption ability and the practical application value are investigated. The functionalized D301 resins possess strong adsorption ability toward phenol by ways of hydrogen bond interaction. The adsorption capacity of Tyr-D301, Phe-D301, and Ala-D301 is 388.2, 368.4, and 321.5 mg· g−1 at 293 K and pH of 2, respectively. The adsorption process could be described satisfactorily by Lagergren-first-order model and Langmuir model. The rate constant is 0.057, 0.042, and 0.035 min−1, respectively. The functionalized D301 can be used to dispose wastewater containing phenols. [ABSTRACT FROM AUTHOR]

A new furostan type steroidal saponin, kingianoside Z (1), along with four known compounds (2-5), was isolated from the ethanolic extract of Polygonatum sibiricum Delar. ex Redoute. Their structures were determined by spectroscopical method and by comparison with previously reported spectroscopic data. Compounds 3-5 showed significant cytotoxicity against HepG2 cell lines with IC50 values of 14.2, 12.1 and 8.5 μM, respectively. [ABSTRACT FROM AUTHOR]

The bubble breakup mechanism in a venturi-type bubble generator is a hot research topic, and the bubble breakup mechanisms induced by the axial regional flow field characteristics has long been studied and debated. A coupled volume of fluid and large eddy simulation numerical simulation method was conducted within the OpenFOAM® framework to track the two-phase interfaces and transient turbulence characteristics of the flow field in a venturi-type bubble generator. A turbulence inlet database was established to ensure the reliability of the numerical solution and the economy of the calculation. The results indicated that the bubble breakup induced by the axial regional flow field characteristics of the divergent section can be divided into a steady-state disturbed breakup pattern and an unsteady-state disturbed breakup pattern macroscopically, the latter playing a dominant role in generating fine bubbles. Furthermore, a series of typical bubble breakup processes were captured via a Lagrangian approach that showed that interfacial instability played an important role at each stage of bubble transport: Kelvin–Helmholtz instability caused bubbles to detach from the gas film during the steady-state disturbed breakup pattern, and Rayleigh–Taylor instability induced the deformation of detached bubbles in the unsteady-state disturbed region. Additionally, viscous shear force strengthened the interfacial instability in the binary breakup process, and turbulent fluctuations and collisions contributed to the shattering of defective bubbles. Moreover, a shearing-off process tended to occur in regions with small vorticity fluctuations, therefore playing a small role in creating large clusters of bubbles. [ABSTRACT FROM AUTHOR]

Low back pain is a common symptom of intervertebral disc degeneration (IDD), which seriously affects the quality of life of patients. The abnormal apoptosis and senescence of nucleus pulposus (NP) cells play important roles in the pathogenesis of IDD. Proanthocyanidins (PACs) are polyphenolic compounds with anti-apoptosis and anti-aging effects. However, their functions in NP cells are not yet clear. Therefore, this study was performed to explore the effects of PACs on NP cell apoptosis and aging and the underlying mechanisms of action. Cell viability was evaluated by cell counting kit-8 (CCK-8) assay. The apoptosis rate was determined TUNEL assays. Levels of apoptosis-associated molecules (Bcl-2, Bax, C-caspase-3 and Caspase-9) were evaluated via western blot. The senescence was observed through SA-β-gal staining and western blotting analysis was performed to observe the expression of senescence-related molecules (p-P53, P53, P21 and P16). Pretreatment with PACs exhibited protective effects against IL-1β-induced NP cell apoptosis including apoptosis rate, expressions of proapoptosis and antiapoptosis related genes and protein. PACs could also alleviate the increase of p-p53, P21, and P16 in IL-1β-treated NP cells. SA-β-gal staining showed that IL-1β-induced senescence of NP cells was prevented by PACs pertreatment. In addition, PACs activated PI3K/Akt pathway in IL-1β-stimulated NP cells. However, these protected effects were inhibited after LY294002 treatment. The results of the present study showed that PACs inhibit IL-1β-induced apoptosis and aging of NP cells by activating the PI3K/Akt pathway, and suggested that PACs have therapeutic potential for IDD. [ABSTRACT FROM AUTHOR]

Plant-derived natural products have been the highly significant sources of novel antitumor agents. The cassane-type diterpenes of genusCaesalpiniahave been reported to bear antiproliferative activities toward different types of cancer cells. In this study, we evaluated the antineoplasmic activities of 16 natural origin cassane-type diterpenes isolated from the CHCl3extract of the seeds ofC. minaxin pituitary adenomas cells and identified caesalpin G (CAG) showed the strongest cytotoxicity. Moreover, we further investigated the structure–activity relationship and molecular mechanism of these derivatives systematically. The results confirmed the unsaturated lactone-type ring, hydroxyl at C-7, and alkenyl at C-11 or C-14 functionality as critical for anticancer activity in this family of natural products. In addition, the mechanism experiments also demonstrated unfolded protein response and ER stress and Wnt/β-catenin pathway were involved in the CAG-induced apoptosis. [ABSTRACT FROM PUBLISHER]

This paper presents rigorous analytical solutions for cavity contraction analysis of a thick-walled cylinder/sphere after an arbitrary magnitude of expansion. Closed-form solutions are given for the distribution of stress and displacement within the cylinder/sphere of soil that is subjected to constant external pressure and monotonically decreasing internal pressure. The soil is modelled as an elastic-perfectly plastic material obeying the Mohr-Coulomb yield criterion and a non-associated flow rule. Large strain effects are taken into account by adopting the logarithmic strain definition in the plastic deformation analysis. The new solutions are validated with published results at first, then parametric studies are carried out. It is shown that the reference stress state (e.g. in-situ, elastic, partially plastic and fully plastic) and the cavity geometry ratio may greatly affect the unloading behaviour, in particular, when the cavity geometry ratio is smaller than a limit value. Finally, three typical applications of the solutions are demonstrated, including (i) design of the thickness of frozen cylinder walls accounting for large deformation effects, (ii) interpretation of laboratory pressuremeter tests with consideration of effect of the constant stress boundary, and (iii) shakedown analysis of a soil cylinder/sphere considering its geometry changes upon cyclic loading and unloading. [ABSTRACT FROM AUTHOR]

Phytochemical investigation on the 90% EtOH extract of the seeds of Cipadessa cinerascensa led to the isolation of three new limonoids, cinerascenoids A-C (1-3). Structural elucidation of all the compounds were performed by spectral methods such as 1D and 2D (¹H-¹H COSY, HMQC, and HMBC) NMR spectroscopy. All the limonoids were in vitro evaluated for their antimicrobial activities against six pathogenic microorganisms. Limonoids 1 and 2 exhibited some activities against three Gram negative bacteria with MIC values less than 60μg/ml. [ABSTRACT FROM AUTHOR]

Objective: Race disparities exist in bone metastasis (BM) development and survival in lung cancer (LC) patients. The Surveillance, Epidemiology, and End Results (SEER) database was used to investigate different patterns of BM development and survival in different races. Design: LC patients with BM were identified from the database from 2010 to 2014. Risk factors were investigated by univariable and multivariable logistic regression. Potential factors for prognosis were evaluated by univariable and multivariable Cox regression. Results: Asian and Pacific Islander (API) patients presented the highest prevalence of BM (24.6%), followed by white (20.7%) and black patients (19.9%) (χ2 = 78.74; p <.001). After adjusting for the demographic and clinical factors, API race was independently associated with a high risk of BM development. The median survival times for the API, white and black LC patients with BM were 16 months (95% CI: 15.2–16.8), 11 months (95% CI: 10.9–11.1) and 10 months (95% CI: 9.7–10.3), respectively, with significant differences (p <.001). Multivariable Cox regression showed that API race was positively associated with greater overall survival compared with white and black patients. Male gender, larger tumor size, lymph node involvement, lower tumor differentiated grade, and the presence of lung, liver and brain metastases were independently associated with a high risk of developing BM and worse survival with LC across all races. Age, income, insurance and histological types had different impacts on BM among different races. Conclusion: Homogeneous and heterogeneous associated factors for BM were revealed among different races. Individualized screening and treatment should be performed race-specifically. [ABSTRACT FROM AUTHOR]

A new ursane-type triterpene, cymosic acid (1) together with two known compounds, 3β,19α-dihydroxy-2-oxo-12-ursen-28-oic acid (2) and 2α,19α-dihydroxy-3-oxo-12-ursen-28-oic acid (3), were isolated from Rosa cymosa Tratt. The structure of compound 1 was elucidated by analyzing its 1H and 13C NMR, 1H–1H COSY, HSQC, HMBC, NOESY, and HR-ESI-MS values. The three compounds were found to display moderate inhibitory activities against nitric oxide production in lipopolysaccharide-activated macrophage cell lines, RAW 264.7 cells. [ABSTRACT FROM AUTHOR]

Aristolochic acid (AA) are persistent soil pollutants in the agricultural fields of the Balkan Peninsula. Preparations containing aristolochic acid are widely used for anti-inflammatory, diuretic, etc. To study the hepatotoxicity of aristolochic acid, 80 healthy SD rats were selected and divided into 20 mg/kg- AA group, 4 mg/kg-AA group, and 2 mg/kg-AA group and blank group, 20 rats per group. Mainly tested the body weight, liver function, liver tissue oxidative stress and pathological changes of liver tissue in rats. The ALT and AST activities in the serum of the rats in the administration groups were increased compared with the blank group. The activity of MDA in the administration groups was higher than that in the blank group; the activities of SOD, T-AOC and GSH-PX were significantly lower than those in the blank group. HE tissue sections also found that the administration groups showed varying degrees of hepatocyte boundary blur, nuclear fragmentation, and fibrosis tendency. Transmission electron microscopy showed that the mitochondria of the rat liver became more and more severely damaged with the increase of dose. Compared with the blank group, the mRNA expression of Bax, Caspase-9 and Caspase-3 in the administration groups were determined, while the mRNA expression of the Bcl-2 was increased. And compared with the blank control group, the expression levels of apoptotic proteins caspase-9 and caspase-3 increased significantly in the 20 mg/kg-AA group. Aristolochic acid can induce liver injury in rats through oxidative stress pathway and mitochondrial apoptosis pathway. [ABSTRACT FROM AUTHOR]

This work studied the changes in microbiological and physiochemical properties during the fermentation of Suan yu by liquid smoking and traditional smoking (batches B, C, and A). Lactobacillus plantarum, Pediococcus pentosaceus, Saccharomyces cerevisiae, and Hansenula polymorpha were the dominant microorganisms in the three samples. Only the acid-resistant Staphylococcus xylosus and Staphylococcus carnosus survived in the acid environment of the final fermented products. The amounts of Enterobacteriaceae, Enterococci, and Pseudomonades in the final fermented products were under the detection limit. Batch B and C samples had higher rate of reduction in pH (4.24 ± 0.17–4.39 ± 0.18 from 6.21 ± 0.24, respectively) and lower acetic acid generation rate (0.06%±0. 00% and 0.05%±0. 00%, respectively) than batch A samples. Large amounts of free amino acids were generated during the fermentation of the samples. Batches B and C had thiobarbituric acid reactive substances (TBARS) value between 0.88 ± 0.03 and 0.89 ± 0.03, total volatile basic nitrogen (TVB-N) value between 18.9 ± 0.34 and 18.8 ± 0.33 mg/kg, and benzo(a)pyrene (BaP) content of 0.1 ± 0.00 μg/kg, which was lower than those of fermented Suan yu prepared by traditional smoking. Sensory analysis indicates that these sample groups have unique smoking and fermentation flavor. Consequently, the fermented Suan yu produced through liquid smoking is a kind of fermented aquatic product with full-bodied smoking flavor, palatable acid flavor, abundant nutrition, and high safety. [ABSTRACT FROM AUTHOR]

The inability to access health services when needed is a critical barrier to HIV prevention, treatment and care among men who have sex with men (MSM) and transgender women (TGW). Using data collected in HPTN 075, we explored factors associated with any experienced healthcare-related stigma. HPTN 075 was a cohort study to assess the feasibility of recruiting and retaining MSM and TGW in clinical trials in sub-Saharan Africa. Of 401 MSM and TGW enrolled at four sites (Kisumu, Kenya; Blantyre, Malawi; Cape Town, Soweto, South Africa) 397 contributed to the analysis (79.9% cis-gender and 20.1% TGW). Of these, (45.3%; 180/397) reported one or more of healthcare-related stigma experiences. Most frequently reported experiences included fear to seek healthcare services (36.3%) and avoiding seeking such services because of the discovery of MSM status (29.2%). Few men and TGW (2.5%) reported having been denied health services because of having sex with men. In multivariable analysis, more participants in Soweto [adjusted odds ratio (AOR) = 2.60] and fewer participants in Blantyre (AOR = 0.27) reported any healthcare-related stigma experiences, in comparison to participants in Kisumu. MSM and TGW that did not have a supportive gay community to rely on were more likely to report any healthcare-related stigma experiences (AOR = 1.46), whereas MSM and TGW who reported high social support and who never had engaged in transactional sex were less likely to report such experiences (AOR = 0.76 and AOR = 0.43, respectively). Our results suggest that encouraging support groups for MSM and TGW as well as training and sensitizing healthcare staff, and the general community, on MSM and TGW health issues and cultural competence may reduce stigma, improve access to healthcare, which could ultimately reduce HIV transmission. [ABSTRACT FROM AUTHOR]

In this article, the problem of estimating the model error distribution in a heteroscedastic varying coefficient regression model is considered. A residual-based estimator of the model error distribution is proposed, associated with its asymptotic results. Furthermore, the application of estimated error distribution for testing whether some varying coefficient components are constants or not is investigated. Test statistics based on the Kolmogorov-Smirnov and Cramér-von Mises type functionals of the estimated model error distribution are used to check the null hypothesis. A bootstrap procedure is further proposed to calculate the critical values. Simulation studies are conducted to demonstrate the performance of the proposed test statistics. [ABSTRACT FROM AUTHOR]

This paper examines {10 } twin nucleation and growth under uniaxial tension at the prismatic/basal boundary through both molecular dynamics simulations and continuum mechanics modelling. Our results show that two disconnection dipoles exist on every intrinsic prismatic plane of the crystal which constructs the prismatic/basal boundary. Only one of the two disconnection dipoles is at the nucleus of {10 } twins. The disconnection is activated and glides plane-by-plane along the direction throughout twin growth. The prismatic plane of the matrix is converted to the basal plane of the twin during the sliding of the disconnection. It is also predicted that a twin nucleates when the local gradient of elastic-energy or the average elastic-energy difference along the prismatic/basal boundary exhibit a sharp increase. Furthermore, the critical strain for twin nucleation can be obtained with the aid of local energy-based descriptors, when viewing twin nucleation as an instability phenomenon. Simulations suggest that both the local gradient and spatial average of elastic-energy difference are fundamental quantities behind the onset of twin nucleation at the prismatic/basal grain boundary in hexagonal close-packed metals under uniaxial loadings. Furthermore, results from our simulations and mechanics model, provide the position and the critical strain of the {10 } twin nucleation at the prismatic/basal boundary. [ABSTRACT FROM AUTHOR]

A new bis-γ-pyrone polypropionate compound onchidione II (1), together with three known compounds, was isolated from a marine pulmonate mollusc Onchidium struma, collected at Hainan Island of China. The structure of new compound was determined by extensive spectroscopic analyses including IR, 1D and 2D NMR techniques, and chemical methods. Compounds 1–4 were evaluated for their cytotoxicity against human tumor cell lines HepG-2, A549, and MCF-2. The results showed that compounds 1 and 2 were moderate cytotoxic against HepG-2, A549, and MCF-2 cell lines, with IC50 values from 13.2 to 22.4 μM. [ABSTRACT FROM AUTHOR]

Liaoning cashmere goats are the most precious genetic resources in China. The function of LAMTOR3 [late endosomal/lysosomal adaptor, mitogen-activated protein kinase (MAPK), and mammalian target of rapamycin activator 3/MAPK scaffold protein 1] gene is expressed in the skin of Liaoning cashmere goats. In situ hybridization (ISH) found that LAMTOR3 is expressed in the inner root sheath (IRS) of hair follicles. During the anagen or catagen phase, the expression of LAMTOR3 is higher in secondary hair follicles than in primary hair follicles. Expression of LAMTOR3 in skin cells treated with melatonin or insulin-like growth factor-1 (IGF-1) is lower than in untreated cells. In addition, the simultaneous treatment of fibroblast growth factor 5 and melatonin decrease the expression of LAMTOR3 in skin cells. The simultaneous treatment with melatonin and 10−5 g/L IGF-1 or 10−4 g/L IGF-1 increases the expression of LAMTOR3 gene in skin cells. If Noggin expression is decreased, then LAMTOR3 expression is increased. This hypothesis suggested that LAMTOR3 influences the character of cashmere fiber, and it may regulate the development of hair follicle and cashmere growth by inducing the MAPK signaling pathway. [ABSTRACT FROM AUTHOR]

Two new daphnane diterpenes named tianchaterpenes A and B were isolated from the roots of Stelleropsis tianschanica. Their structures were elucidated on the basis of chemical and spectral analysis, including 1D, 2D NMR analyses and HRESIMS. Compounds 1 and 2 were evaluated for their cytotoxic activities against HeLa and HCT-8 cell lines. The results showed that all compounds displayed weak cytotoxicities to the HeLa cells and were inactive to the HCT-8 cells. [ABSTRACT FROM AUTHOR]

Phytochemical investigation on the stems of Schisandra glaucescens resulted into the isolation of three new lanostane triterpenoids, 12-hydroxyschiglausin B (1), 12-hydroxykadsuphilactone B (2), and 20R-hydroxyschinalactone C (3). Structural elucidation of all the compounds was accomplished by spectral methods. The isolated compounds were tested in vitro for cytotoxic activities. As a result, triterpenoids 1 and 2 showed cytotoxic activities for all six tested tumor cell lines with IC50 values less than 15 μM. [ABSTRACT FROM AUTHOR]

Objective: Several studies have reported the association of benign paroxysmal positional vertigo (BPPV) with vitamin D deficiency. This study aimed to evaluate serum 25-hydroxy vitamin D (25 (OH) D) levels in native Chinese postmenopausal women with de novo idiopathic BPPV and to investigate the possible relationship between the occurrence of BPPV and low 25 (OH) D levels. Methods: This retrospective study comprised of 85 postmenopausal women with de novo idiopathic BPPV and 80 age-matched healthy controls. All subjects had bone mineral density (BMD) and serum 25 (OH) D levels measurements recorded, and the results were compared. Results: The prevalence of reduced BMD (T score <−1.0) was significantly higher in female patients with BPPV than in healthy controls (71.8% vs. 51.2%, p = .004). The mean serum 25 (OH) D levels were also significantly lower in female patients with BPPV than in healthy controls (19.1 ± 5.2 vs. 22.5 ± 5.8, p < .001). The regression analyses demonstrated that vitamin D deficiency was associated with BPPV with an odds ratio of 2.1 (95% confidence interval = 1.1-3.1, p = .031). Conclusion: Our study suggests that low 25 (OH) D may be a risk factor for BPPV in postmenopausal women. [ABSTRACT FROM AUTHOR]

A new cyclolanostane triterpenoid glycoside, soulieoside O (1), together with 25-O-acetylcimigenol-3-O-β-d-xylopyranoside (2) and cimigenol-3-O-β-d-xylopyranoside (3), was isolated from the rhizomes ofSouliea vaginata. Their structures were characterized by spectroscopic analysis and chemical methods. The new compound showed moderate inhibitory activity against three human cancer cell lines with IC50values of 9.3–22.5 μM. [ABSTRACT FROM PUBLISHER]

Two new triterpene saponins, clinopodiside VI (1) and saikosaponin c (2), along with six known saikosaponins (3–8), were isolated from the plant ofClinopodium polycephalum.Compounds1–3showed moderate inhibition against H9c2 cell damage induced by H2O2. [ABSTRACT FROM PUBLISHER]

Two new steroidal glycosides ponasteroside C (1) and ponasteroside D (2) were isolated from the aerial parts ofLepidogrammitis drymoglossoides. Their structures were elucidated by various spectroscopic techniques (IR, HRESIMS, 1D and 2D NMR). All compounds were evaluated for their cytotoxicity against HeLa and HCT-8 cell lines, and compounds1and2showed mild activity against all the test cell lines. [ABSTRACT FROM PUBLISHER]

A new phenylethanoid glycoside, 3′′′-O-methylcampneoside I (1), was isolated from the 90% ethanolic extract of the roots ofIncarvillea compacta, together with three known compounds, campneoside I (2), ilicifolioside A (3), and campneoside II (4). Their structures were determined spectroscopically and compared with previously reported spectral data. Compound1existed as epimers and displayed better 1,1-diphenyl-2-picrylhydrazyl (DPPH)-free radical scavenging activity using di-tert-butyl-4-methylphenol (BHT) as the positive control. In addition, pretreatment of human HepG2 cells with compound1significantly increased the viability on CCl4-induced cell death. [ABSTRACT FROM PUBLISHER]