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Two temporal second-order energy stable schemes with variable time step sizes are constructed for the time fractional Cahn–Hilliard model. Nonuniform L1 + formula is utilized for the discretization of the fractional derivative, while the nonlinear term is handled by the fully-implicit scheme and the scalar auxiliary variable method, respectively. By means of the recently proposed discrete gradient structure of the temporal discretization operator, the discrete energy dissipation laws are developed via a unified framework, which are stronger than the energy boundedness results reported in the previous literature. Moreover, the discrete energy decay nature coincides with the classical analogies as the fractional order tends to one. The optimal convergence rate is verified numerically, furthermore, the coarsening dynamics simulation demonstrates the efficiency of the variable-step schemes combined with the adaptive time strategy. [ABSTRACT FROM AUTHOR]

Abstract: Hip axis length (HAL) has been proposed as an independent predictor of hip fracture risk in Caucasian females. There are, however, few data concerning its predictive risk in Chinese. The aim of this study was to investigate the changes of HAL in healthy Chinese population and the relationship between HAL and femoral neck fracture. The study population included 10,554 healthy Chinese people (8665 females, 1889 males) aged 20–97 yrs living in Shanghai. Cases were 106 patients (82 females, 24 males) aged 52 yrs old and over with femoral neck fracture. Controls were 106 age-matched healthy persons. All subjects were measured bone mineral density (BMD) at any site of proximal femur and HAL using dual-energy X-ray absorptiometry. HAL had significantly positive correlations with height and weight. After the adjustment of height and weight, HAL increased with age at 50 yrs of age and over in females, and no difference was found among the age groups in males. Males had longer HAL than females in all age groups. The peak BMD appeared in 30–44 yrs for females and 20–24 yrs for males and decreased thereafter, especially for females at 50 yrs old and over. HAL was similar in both fracture and control groups, whereas the BMD values at proximal femur were significantly lower in fracture group than in controls. There was no evidence that subjects with femoral neck fracture had longer HAL. Because of the limitations of retrospective study and relatively small fracture sample, prospective studies are required to determine the conclusions. [Copyright &y& Elsevier]

Abstract: Our study surveyed age-related bone mineral density (BMD), bone loss rate, and prevalence of osteoporosis in women at multiple research centers in China. Survey results were used to establish a BMD reference database for the diagnosis of osteoporosis in Chinese women nationwide. We used dual-energy X-ray absorptiometry bone densitometers to measure BMD at posteroanterior (PA) lumbar spine (L1–L4; n=8142) and proximal femur (n=7290) in female subjects of age 20–89yr from Beijing, Shanghai, Guangzhou, Chengdu, Nanjing, and Jiaxing. A cubic regression-fitting model was used to describe the change of BMD with age at various skeletal sites. Peak BMD occurred between 30 and 34yr of age for femur neck and total femur, and between 40 and 44yr for spine and trochanter measurement sites. Young adult (YA) BMD values (mean and standard deviation [SD], calculated as the average BMD in the age range of 20–39, were 1.116±0.12, 0.927±0.12, 0.756±0.11, and 0.963±0.13g/cm2 at PA spine, femoral neck, trochanter, and total femur, respectively. The BMD of 85-yr-old women reflected a loss of 32% at the spine and 30–35% at femur measurement sites. The prevalence of osteoporosis, defined as a BMD of ≤−2.5 SDs from YA values established in this study, in female subjects of age 50yr or older, was 28% for the spine, 15% for any femur site, and 31% for any spine or femur site. This study provides important information for formulating osteoporosis prevention and treatment strategies in Chinese women, and it establishes a reliable BMD reference database for the diagnosis of osteoporosis of Chinese women nationwide. [Copyright &y& Elsevier]

In a closed ecologic niche in organism hydrogen-producing fermentation reactor, non-organism factors to influence organism fermentation rate and fermentation product ingredient normally contain temperature, pH and organic elements, etc. Physiological ecology is about how organism adapts the change of ecological factors in the ecologic niche through physiological reaction and adjustment. This adjustment is very important for acid-producing phase fermentation bacteria to adapt the change of ecological factors and influences terminal fermentation product ingredient. Each kind of fermentation bacteria has special fermentation types, such as propionic acid fermentation, butyric acid fermentation, ethanol fermentation or lactic acid fermentation, etc. When ecological factors change, fermentation bacteria will also change conversion rate of all terminal fermentation products through normal physiological regulation of organism even if fermentation-type does not change. Butyric acid-type fermentation type in acid-producing phase often occurs during two-phase anaerobic biological treatment. Terminal fermentation products of butyric acid-type fermentation usually contain a lot of propionic acid product. As a matter of fact, this is a consequence to adjust physiological metabolism equilibrium of fermentation bacteria. If ethanol is terminal product of liquid phase, effect of terminal product on normal metabolic process not only can be avoided, but also orderly fermentation can be obtained for oxidation–reduction. Hydrogen partial pressure in the reactor greatly influences ethanol conversion rate. It is known that ethanol can be accumulated only when hydrogen partial pressure is more than . When hydrogen partial pressure is below , ethanol will be converted to acetic acid. By control of fermentation bacteria at an ecological environment phase anaerobic biological treatment is one of the advantages of two-phase anaerobic biological treatment technique. [Copyright &y& Elsevier]

Abstract: The potential energy surface of the H13 proton in base cytosine of the DNA molecules is calculated ab initio at the Gaussian98 MP2/6-311G level. Two potential wells are found. One corresponds to the normal cytosine, while the other corresponds to its imino tautomer. The bindings of the proton in these wells are stable enough against the thermo-disturbance. The motions of the proton in these wells are oscillations around the nearest nitrogen atom like the pendula, and may move far away from the nitrogen atom to form the hydrogen bond with other bases. The estimated tunneling probability of the H13 proton from one well to another well shows that the life time of the proton staying in one of these wells is about . It is too long to let tautomers of cytosine be in thermodynamical equilibrium in a room temperature gas phase experiment. The biological significance of this result is discussed. [Copyright &y& Elsevier]

Bipolaris sorokiniana is a fungal pathogen that caused root rot and spot blotch on wheat. A Recombinase Polymerase Amplification (RPA) assay was developed to detect B. sorokiniana specifically based on the sequences of calmodulin gene sequence. The specificity of RPA assay was tested against 19 fungal organisms associated with wheat, and the detection limit was determined to be 10 pg for B. sorokiniana pure fungal DNA. Further, the RPA assay was capable of detecting B. sorokiniana from artificially inoculated and field collected wheat tissues directly. These results indicate that the RPA assay is rapid and effective method for detection and molecular identification of B. sorokiniana. • A rapidly detection method of B. sorokinian was developed based on Recombinase Polymerase Amplification (RPA). • The RPA assay have the same sensitivity with PCR assay in detecting B. sorokiniana. • The RPA assay could potentially be utilized in molecular identification and routine diagnostics of B. sorokiniana. [ABSTRACT FROM AUTHOR]

Abstract: The defect models of La3+: PbWO4 (PWO) for different doping concentrations are discussed by defect chemistry and the optimal substituting positions of the impurity La3+ ions are obtained using the General Utility Lattice Program (GULP). The calculated results indicate that, in the lightly doped La3+: PWO crystal, the main compensating mechanism is [2La+ Pb +V2− Pb], and in the heavily doped La3+: PWO crystal, it will bring interstitial oxygen ions to compensate the positive electricity caused by La+ Pb, forming defect cluster [2La+ Pb +O2− i ] in the crystal. The electronic structures of the La3+: PWO with the optimal defect models are calculated using the DV-Xα method. It can be concluded from the electronic structures that, for lightly doped case, the energy gap of the crystal would be broaden and the 420 nm absorption band will be restricted; for heavily doped case, because of the existence of interstitial oxygen ions, it can bring new absorption bands and reduce the radiation hardness of the crystal. [Copyright &y& Elsevier]

Gap junctions, which is formed by connexins, has been proved to play an important role in the atherogenesis development. Rutaecarpine was reported to inhibited monocyte migration, which indicates its potential for anti-atherosclerosis activity. This study evaluated the effect of rutaecarpine on endothelial dysfunction, and focused on the regulation of connexin expression in endothelial cells by rutaecarpine. Endothelia damage was induced by exposing HUVEC-12 to Ox-LDL (100 mg/l) for 24 h, which decreased the expression of protective proteins Cx37 and Cx40, but induced atherogenic Cx43 expression, in both mRNA and protein levels, concomitant with the impaired propidium iodide diffusion through the gap junctions. Pretreatment with rutaecarpine effectively recovered the expression of Cx37 and Cx40, but inhibited Cx43 expression, thereby improving gap junction communication and significantly prevented the endothelial dysfunction. Consequently, the cell viability and nitric oxide production were increased, lactate dehydrogenase production was decreased and monocyte adhesion was inhibited. These protective effects of rutaecarpine were remarkably attenuated by pretreatment with capsazepine, a competitive antagonist of transient receptor potential vanilloid subtype 1 (TRPV1). In summary, this study is the first to report that rutaecarpine prevents endothelial injury and gap junction dysfunction induced by Ox-LDL in vitro, which is related to regulation of connexin expression patterns via TRPV1 activation. These results suggest that rutaecarpine has the potential for use as an anti-atherosclerosis agent with a novel mechanism. [ABSTRACT FROM AUTHOR]

Vascular endothelial insulin resistance (IR) is a critically initial factor in cardiocerebrovascular events resulted from diabetes and is becoming a worldwide public health issue. Thiazolidinediones (TZDs) are clinical insulin-sensitizers acting through a canonical peroxisome proliferator-activated receptor gamma (PPARγ)-dependent insulin trans-activation pathway. However, it remains elusive whether there are other mechanisms. In current study, we investigated whether TZDs improve endothelial IR induced by high glucose concentration or hyperglycemia via a non-canonical PPARγ-dependent nuclear factor-kappa B (NF-κB) trans-repression pathway. Our results showed that pre-treatment with TZDs dramatically decrease the susceptibility of endothelial cell to IR, while post-treatment notably improve the endothelial IR both in vitro and in vivo . Moreover, TZDs substantially increase the levels of endothelial nitric oxide synthase (eNOS) and inhibitory κB alpha (IκBα), whereas decrease those of the phosphorylated inhibitory κB kinase alpha/beta (phosphor-IKKα/β) and the cytokines including tumor necrosis factor alpha (TNFα), interleukin-6 (IL-6), soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cellular adhesion molecule-1 (sVCAM-1), suggesting that TZDs act indeed through a PPARγ-dependent NF-κB trans-repression pathway. These findings highlighted a non-canonical mechanism for TZDs to ameliorate endothelial IR which might provide a potential strategy to prevent and treat the diabetic vascular complications clinically. [ABSTRACT FROM AUTHOR]

In this study, three novel multi-sparger multi-stage airlift loop membrane bioreactors (Ms2ALMBRs) were set up in parallel for treating synthetic high-strength 7-ACA pharmaceutical wastewater under different HRTs, temperatures and pHs, respectively. During the 200-day operating time, average COD removal efficiencies were 94.96%, 96.05% and 93.9%. While average 7-ACA removal efficiencies were 66.44%, 59.04% and 59.60%, respectively. The optimal conditions were 10 h, 15-35 °C and 7-9 for HRT, temperature and pH, respectively. Moreover, the sludge characteristics and microorganism drug-resistances were explored. Results showed that different temperatures and pHs influenced contaminant removals by affecting MLSS concentration and β-lactamase activity significantly. In addition, mathematical statistical models, built on the polynomial and linear regression techniques, were developed for exploring the inner relationships between HRT, temperature and pH changes and MLSS concentrations, β-lactamase activities and contaminant removals of the Ms2ALMBR system. [ABSTRACT FROM AUTHOR]

Growth and lipid production performance of Scenedesmus sp. under different culture modes were investigated. Under heterotrophic aerobic mode, algal biomass concentration and total lipid content reached 3.42 g L-1 and 43.0 wt.%, which were much higher than those in autotrophic aerobic mode (0.55 g L-1/20.2 wt.%). The applied light exposure of 7.0 W m-2 was beneficial to biomass and lipid accumulation. Mixotrophic aerobic mode produced the highest biomass concentration of 3.84 g L-1. The biomass was rich in lipids (51.3 wt.%) and low in proteins (17.9 wt.%) and carbohydrates (10.3 wt.%). However, lower algal biomass concentration (2.93 g L-1) and total lipid content (36.1 wt.%) were obtained in mixotrophic anaerobic mode. Mixotrophic aerobic mode gave the maximum heat value conversion efficiency of 45.7%. These results indicate that mixotrophic aerobic cultivation was a promising culture mode for lipid production by Scenedesmus sp. [ABSTRACT FROM AUTHOR]

Limited-oxygen mediated synergistic relationships between sulfate-reducing bacteria (SRB), nitrate-reducing bacteria (NRB) and sulfide-oxidizing bacteria (SOB, including nitrate-reducing, sulfide-oxidizing bacteria NR-SOB) were predicted to simultaneously remove contaminants of nitrate, sulfate and high COD, and eliminate sulfide generation. A lab-scale experiment was conducted to examine the impact of limited oxygen on these oxy-anions degradation, sulfide oxidation and associated microbial functional responses. In all scenarios tested, the reduction of both nitrate and sulfate was almost complete. When limited-oxygen was fed into bioreactors, S0 formation was significantly improved up to ~70%. GeoChip 4.0, a functional gene microarray, was used to determine the microbial gene diversity and functional potential for nitrate and sulfate reduction, and sulfide oxidation. The diversity of the microbial community in bioreactors was increased with the feeding of limited oxygen. Whereas the intensities of the functional genes involved in sulfate reduction did not show a significant difference, the abundance of the detected denitrification genes decreased in limited oxygen samples. More importantly, sulfide-oxidizing bacteria may alter their populations/genes in response to limited oxygen potentially to function more effectively in sulfide oxidation, especially to elemental sulfur. The genes fccA/fccB from nitrate-reducing, sulfide-oxidizing bacteria (NR-SOB), such as Paracoccus denitrificans, Thiobacillus denitrificans, Beggiatoa sp., Thiomicrospira sp., and Thioalkalivibrio sp., were more abundant under limited-oxygen condition. [ABSTRACT FROM AUTHOR]

Persistent hyperglycemia increases a systemic oxidative stress, causing the onset of vascular endothelial dysfunction and atherosclerosis. Diallyl trisulfide (DAT), a natural organosulfur compound in garlic, has been reported to have actions of dilating blood vessels and antibacteria, etc. In this study, models of obese diabetic rat in vivo and high glucose concentration (HG)-induced endothelial cell injury in vitro were used to investigate the protective effects of DAT on vascular endothelial injury and its underlying mechanisms. In the in vivo model, the obese diabetic rats were injected venously with DAT (5.0mgkg−1 d−1) and Vitamin E (1.0mgkg−1 d−1) respectively, once daily for 7 consecutive days. In the in vitro model, HG-injured HUVEC were treated with or without DAT (25µmolL−1, 50µmolL−1, 100µmolL−1) or Vitamin E (25µmolL−1) respectively for 24h. The extents of vascular endothelial injury and protective effects of DAT were evaluated. The results both in vivo and in vitro displayed that DAT-treatment significantly attenuated the endothelial cell impairments. Besides, DAT-treatment markedly decreased the levels of malondialdehyde (MDA) and reactive oxygen species, whereas elevated the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in mitochondrium. Moreover, DAT-treatment considerably improved mitochondrial respiration function. Taken together, our results suggest that DAT protects vascular endothelium from HG or hyperglycemia induced-injury by reducing mitochondrial oxidative stress. The findings provide a novel insight for DAT to potentially treat the oxidative stress diseases, i.e., atherosclerosis, diabetes, and neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Abstract: Anoxic preconditioning (APC) attenuates myocardial injury caused by ischemia/reperfusion. The protective mechanisms of APC involve up-regulation of the protective proteins and inhibition of apoptosis. 14-3-3 protein, as a molecular chaperone, plays an important role in regulating cell survival and apoptosis. However, the role of 14-3-3 protein in cardioprotection of APC and the pathways determining 14-3-3 protein expression during APC are not clear. In this work, Western blotting analysis was used to detect the 14-3-3 protein expression and activity of extracellular signal-regulated protein kinase 1/2 (ERK1/2) in cardiomyocytes subjected to anoxia–reoxygenation injury with and without APC and control. The cardiomyocytes from APC group were more resistant to injury induced by anoxia–reoxygenation and had much stronger phosphorylation of ERK1/2 than the control. The 14-3-3 protein expression was positively correlated with the phosphorylation of ERK1/2. Furthermore, inhibition of the ERK1/2 with PD98059 abolished the 14-3-3 protein up-regulation in cardiomyocytes induced by APC. The results indicate that APC up-regulates 14-3-3 protein expression through the ERK1/2 signaling pathways. [Copyright &y& Elsevier]