Chondrosterins A–E, Triquinane-Type Sesquiterpenoids from Soft Coral-Associated Fungus Chondrostereum sp.

The marine fungus Chondrostereum sp. was collected from a soft coral Sarcophyton tortuosum from the South China Sea. This fungus was cultured in potato dextrose broth medium and the culture broth was extracted with EtOAc. Five new triquinane-type sesquiterpenoids, chondrosterins A–E (1–5), and the known sesquiterpenoid hirsutanol C (6), were isolated. The structures were elucidated mainly on the basis of NMR, MS, and X-ray single-crystal diffraction data. Chondrosterin A (1) showed significant cytotoxic activities against cancer lines A549, CNE2, and LoVo with IC50 values of 2.45, 4.95, and 5.47 μM, respectively

Effects of physical properties on the compression wave speed of seafloor sediment in the South China Sea: Comparisons between theoretical models and measured data

The compression wave speed and physical properties of seafloor sediments are significant in marine engineering and marine acoustics. Although most regression equations can be satisfactorily fitted to the data and provide a useful predictive method, there is little insight into the influence of physical properties on the compression wave speed of seafloor sediment in the South China Sea (SCS). To characterize the compression wave speed and physical properties of seafloor sediments, the compression wave speed, porosity, density, and mean grain size were measured and calculated for forty-two samples collected from the South China Sea. The results show that the RMS roughness of seafloor sediment in the South China Sea ranges from 0.2 to 15 μm, and the porosity and density are determined by the RMS roughness and mean grain size. The relationships between the compression wave speed and physical properties of seafloor sediments are consistent with the intergranular friction model. When we have the physical parameters but no compression wave speed, therefore, the intergranular friction model can be used to predict the compression wave speed of seafloor sediment. Compared with the Wood model curve, we also reveal that the intergranular friction of seafloor sediment is an important parameter in determining the compression wave speed

Overtone spectra and intensities of tetrahedral molecules in boson-realization models

The stretching and bending vibrational spectrum and the intensities of infrared transitions in a tetrahedral molecule are studied in two boson-realization models, where the interactions between stretching and bending vibrations are described by a quadratic cross term and by Fermi resonance terms, called harmonically coupled and Fermi resonance boson-realization model, respectively. The later is a development of our recent model. As an example, the two models are applied to the overtone spectrum and the intensities of silicon tetrafluorde. Those models provide fits to the published experimental vibrational eigenvalues with standard deviations 1.956 cm$^{-1}$ and 0.908 cm$^{-1}$, respectively. The intensities of infrared transitions of its complete vibrations are calculated in the two models, and results show a good agreement with the observed data.Comment: 14 pages Revtex, no figure, to appear in Annals of Physic

Communication security of autonomous ground vehicles based on networked control systems: The optimized LMI approach

The paper presents a study of networked control systems (NCSs) that are subjected to periodic denial-of-service (DoS) attacks of varying intensity. The use of appropriate Lyapunov–Krasovskii functionals (LKFs) help to reduce the constraints of the basic conditions and lower the conservatism of the criteria. An optimization problem with constraints is formulated to select the trigger threshold, which is solved using the gradient descent algorithm (GDA) to improve resource utilization. An intelligent secure event-triggered controller (ISETC) is designed to ensure the safe operation of the system under DoS attacks. The approach is validated through experiments with an autonomous ground vehicle (AGV) system based on the Simulink platform. The proposed method offers the potential for developing effective defense mechanisms against DoS attacks in NCSs

Adenosine A2A Receptors Mediate Anti-Inflammatory Effects of Electroacupuncture on Synovitis in Mice with Collagen-Induced Arthritis

To study the role of adenosine A2A receptor (A2AR) in mediating the anti-inflammatory effect of electroacupuncture (EA) on synovitis in collagen-induced arthritis (CIA), C57BL/6 mice were divided into five treatment groups: Sham-control, CIA-control, CIA-EA, CIA-SCH58261 (A2AR antagonist), and CIA-EA-SCH58261. All mice except those in the Sham-control group were immunized with collagen II for arthritis induction. EA treatment was administered using the stomach 36 and spleen 6 points, and stimulated with a continuous rectangular wave for 30 min daily. EA treatment and SCH58261 were administered daily from days 35 to 49 (n=10). After treatment, X-ray radiography of joint bone morphology was established at day 60 and mouse blood was collected for ELISA determination of tumor necrosis factor alpha (TNF-α) levels. Mice were sacrificed and processed for histological examination of pathological changes of joint tissue, including hematoxylin-eosin staining and immunohistochemistry of A2AR expression. EA treatment resulted in significantly reduced pathological scores, TNF-α concentrations, and bone damage X-ray scores. Importantly, the anti-inflammatory and tissue-protective effect of EA treatment was reversed by coadministration of SCH58261. Thus, EA treatment exerts an anti-inflammatory effect resulting in significant protection of cartilage by activation of A2AR in the synovial tissue of CIA

Prevalence of Deliberate Self-harm Among Chinese Patients With Heroin Dependence: A Meta-Analysis

Background: There is paucity of data regarding the prevalence and methods of deliberate self-harm (DSH) in patients with heroin dependence in international literature. In China, there have been a few studies investigating the prevalence of DSH in heroin-dependent patients (HDPs), but their rates varied widely. We thus conducted a meta-analysis of studies assessing the prevalence of DSH among Chinese HDPs.Methods: Relevant studies were retrieved from major Chinese databases (China National Knowledge Infrastructure, Wanfang data, and SinoMed) and western databases (PubMed, EMBASE, and PsycInfo). Two authors independently identified eligible studies and extracted data. Studies that included a representative sample of Chinese HDPs and ascertained DSH caseness in a reliable way were considered as high quality. Statistical analysis was performed using R software.Results: In total, 15 eligible studies with a total of 37,243 Chinese HDPs were included. All included studies were conducted in heroin detoxification settings. Only two studies were rated as high quality. The pooled prevalence of DSH in Chinese HDPs was 4.4% (95%CI: 2.9, 6.2%), but the heterogeneity of prevalence rates across studies was significant (I2 = 98%, P < 0.001). Studies rated as high quality had significantly higher prevalence of DSH than those rated as low quality (13.2 vs. 3.4%, P < 0.001). Swallowing foreign objects was the most common method of DSH, with a combined prevalence of 2.7% (95%CI: 1.6, 4.4%). Extreme DSH methods such as cutting off fingers and jumping from height were also not uncommon in this patient population.Conclusion: Due to methodological problems in available studies, we find a relatively low prevalence of DSH among Chinese HDPs receiving detoxification treatment. Nevertheless, the self-harmers of Chinese HDPs are more likely to harm themselves in a dangerous or life-threatening way. Restricting the availability of DSH methods may be an effective way to prevent or reduce DSH in China's detoxification treatment settings

Immobilizing lead and copper in aqueous solution using microbial- and enzyme-induced carbonate precipitation

Inappropriate irrigation could trigger migration of heavy metals into surrounding environments, causing their accumulation and a serious threat to human central nervous system. Traditional site remediation technologies are criticized because they are time-consuming and featured with high risk of secondary pollution. In the past few years, the microbial-induced carbonate precipitation (MICP) is considered as an alternative to traditional technologies due to its easy maneuverability. The enzyme-induced carbonate precipitate (EICP) has attracted attention because bacterial cultivation is not required prior to catalyzing urea hydrolysis. This study compared the performance of lead (Pb) and copper (Cu) remediation using MICP and EICP respectively. The effect of the degree of urea hydrolysis, mass and species of carbonate precipitation, and chemical and thermodynamic properties of carbonates on the remediation efficiency was investigated. Results indicated that ammonium ion (NH4+) concentration reduced with the increase in lead ion (Pb2+) or copper ion (Cu2+) concentration, and for a given Pb2+ or Cu2+ concentration, it was much higher under MICP than EICP. Further, the remediation efficiency against Cu2+ is approximately zero, which is way below that against Pb2+ (approximately 100%). The Cu2+ toxicity denatured and even inactivated the urease, reducing the degree of urea hydrolysis and the remediation efficiency. Moreover, the reduction in the remediation efficiency against Pb2+ and Cu2+ appeared to be due to the precipitations of cotunnite and atacamite respectively. Their chemical and thermodynamic properties were not as good as calcite, cerussite, phosgenite, and malachite. The findings shed light on the underlying mechanism affecting the remediation efficiency against Pb2+ and Cu2+

FY2014 Annual Report

Abstract Background This population-based study was designed to investigate whether consumption of sugar-sweetened beverages (SSB) is associated with lower serum total testosterone concentration in men 20–39 years old. Methods All data for this study were retrieved from the National Health and Nutrition Examination Survey (NHANES) 2011–2012. The primary outcome was serum testosterone concentration, and main independent variable was SSB intake. Other variables included age, race/ethnicity, poverty/income ratio, body mass index (BMI), serum cotinine, heavy drinking, and physical activity. Results Among all subjects (N = 545), 486 (90.4%) had normal testosterone levels (defined as ≥231 ng/dL) and 59 (9.6%) had low testosterone levels (defined as < 231 ng/dL). Multivariate logistic regression revealed the odds of low testosterone was significantly greater with increasing SSB consumption (Q4 [≥442 kcal/day] vs. Q1 [≤137 kcal/day]), adjusted odds ratio [aOR] = 2.29, p = 0.041]. After adjusting for possible confounding variables, BMI was an independent risk factor for low testosterone level; subjects with BMI ≥ 25 kg/m2 had a higher risk of having a low testosterone level than those with BMI < 25 kg/m2 (aOR = 3.68, p = 0.044). Conclusion SSB consumption is significantly associated with low serum testosterone in men 20–39 years old in the United States