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In energetic materials, high-energy propellants always encounter poor mechanical properties. Herein, a novel energetic binder nitrate glycerol ether cellulose (NGEC)/hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) composite was prepared by a facile, safe water suspension and freeze-drying technology, and integrated in gun propellant (GP) through semi-solvent manufacturing. A series of characterizations and tests were conducted to characterize the NGEC/RDX-GP. The findings revealed that the mechanical properties in terms of the impact strength of NGEC/RDX-GPs with different content of NGEC was improved by 15.3% ~ 117.1%, 3.9% ~ 34.6%, 6.9% ~ 31.1% under conditions of -40 °C, 20 °C and 50 °C; the compression strength was improved by 2.5% ~ 23.1%, 10.7% ~ 27.9%, 7.3% ~ 28.5%, while the tensile strength was improved by 15.4% ~ 35.0%, 10.4% ~ 33.0%, 11.8% ~ 35.5%, respectively. Besides, the thermal decomposition dynamics and thermodynamics were also investigated to probe the thermal properties of NGEC/RDX-GP. Moreover, the impact and electrostatic spark sensitivity have also been tested and present excepted results compared with neat propellant. In addition, the improved gunpowder impetus of NGEC/RDX-GP indicated that the energetic performance of propellant was further enhanced, and maintained stable combustion behavior. Finally, the enhancement mechanism of the propellant was discussed and proposed. Therefore, this construction strategy and application of NGEC/RDX composites in propellants can provide reliable fundamental theory and data support for the development of high performances propellant. [ABSTRACT FROM AUTHOR]

To evaluate the association of uric acid (UA) with adverse outcomes and its potential mediator in patients with left ventricular diastolic dysfunction (LVDD) and pulmonary hypertension (PH). We retrospectively analyzed 234 patients with LVDD and PH. The baseline characteristics of patients with low UA (≤ 330 µmol/L) group were compared with high UA (> 330 µmol/L) group. Adverse outcomes included all-cause mortality, cardiac death and heart failure (HF) hospitalization. Their association with UA and the mediator were evaluated using Cox regression and mediation analysis. The mediation proportion was further quantified by the R mediation package. During a mean follow-up of 50 ± 18 months, there were 27 all-cause deaths, 18 cardiovascular deaths and 41 incidents of HF hospitalization. Multivariable Cox regression analysis showed UA was an independent risk factor of adverse outcomes in LVDD and PH patients, even after adjusting for age, sex, body mass index, medical histories, systolic blood pressure, fasting blood glucose, total cholesterol, triglyceride, eGFR, BNP and medications. The hazard ratios (HRs) for UA (per 10 µmol/L increase) were as below: for all-cause mortality, HR 1.143, 95% CI 1.069–1.221, P < 0.001; for cardiac death, HR 1.168, 95% CI 1.064–1.282, P = 0.001; for HF hospitalization, HR 1.093, 95% CI 1.035–1.155, P = 0.001. Neutrophil-to-lymphocyte ratio (NLR) played a partial mediation role in the association, and the mediation proportion for NLR on the UA-adverse outcomes were 21%, 19% and 17%, respectively. In patients of LVDD with PH, higher UA level was independently correlated with adverse outcomes. Furthermore, NLR partially mediated the effect of UA on the risk of all-cause mortality, cardiac death and HF hospitalization. [ABSTRACT FROM AUTHOR]

The northern Andaman Sea off Myanmar is one of the relatively high productive regions in the Indian Ocean. The abundance, biomass and species composition of mesozooplankton and their relationships with environmental variables in the epipelagic zone (∼200 m) were studied for the first time during the Sino-Myanmar joint cruise (February 2020). The mean abundance and biomass of mesozooplankton were (1 916.7±1 192.9) ind./m3 and (17.8±7.9) mg/m3, respectively. A total of 213 species (taxa) were identified from all samples. The omnivorous Cyclopoida Oncaea venusta and Oithona spp. were the top two dominant taxa. Three mesozooplankton communities were determined via cluster analysis: the open ocean in the Andaman Sea and the Bay of Bengal (Group A), the transition zone across the Preparis Channel (Group B), and nearshore water off the Ayeyarwady Delta and along the Tanintharyi Coast (Group C). Variation partitioning analysis revealed that the interaction of physical and biological factors explained 98.8% of mesozooplankton community spatial variation, and redundancy analysis revealed that column mean chlorophyll a concentration (CMCHLA) was the most important explanatory variable (43.1%). The abundance and biomass were significantly higher in Group C, the same as CMCHLA and column mean temperature (CMT) and in contrast to salinity, and CMT was the dominant factor. Significant taxon spatial variations were controlled by CMCHLA, salinity and temperature. This study suggested that mesozooplankton spatial variation was mainly regulated by physical processes through their effects on CMCHLA. The physical processes were simultaneously affected by heat loss differences, freshwater influx, eddies and depth. [ABSTRACT FROM AUTHOR]

A serials of nanofibers with different contents of CeO2 were successfully fabricated by electrospinning techniques. The structure, morphology and optical properties were characterized by X-ray diffraction, Scanning electron microscopy, Fourier transform infrared spectra, X-ray photoelectron spectroscopy, UV‒Vis spectroscopy. The catalytic properties of CeO2/g-C3N4 composites were evaluated using tetracycline hydrochloride under simulated solar light illumination. When the loading amount of CeO2 was 5.0 wt %, the composite showed the highest catalytic activity, which was 5.8 times that of porous g-C3N4. The enhanced photocatalytic properties of CeO2/g-C3N4 may be attributed to effective separation of photogenerated carriers and enhanced absorption of visible light. The photocatalyst had an excellent catalytic stability and possible photodegradation mechanism of the obtained sample was proposed. [ABSTRACT FROM AUTHOR]

China's rise has not only propelled China to be the second-largest economy in the world but also produced an increasing socio-economic inequality that undermines the legitimacy of the socialist political system. What do people think of social inequality and social justice? To understand the public attitudes towards the issue of social justice, this article develops a typology of public opinion and social justice to study how people look at social justice in China. A public survey was conducted and analyzed. Our research shows that people tend to use their subjective belief system to view social justice. We find that overall public opinion focuses more on distributional justice and less than procedure fairness. We also find an increasing number of young people who began to pay more attention to policy-making processes and procedural justice. This finding may have an important implication for policymaking as the Chinese government seeks to reduce social instability. [ABSTRACT FROM AUTHOR]

The fusion of infrared and visible images can obtain a combined image with hidden objective and rich visible details. To improve the details of the fusion image from the infrared and visible images by reducing artifacts and noise, an infrared and visible image fusion algorithm based on ResNet-152 is proposed. First, the source images are decomposed into the low-frequency part and the high-frequency part. The low-frequency part is processed by the average weighting strategy. Second, the multi-layer features are extracted from high-frequency part by using the ResNet-152 network. Regularization L1, convolution operation, bilinear interpolation upsampling and maximum selection strategy on the feature layers to obtain the maximum weight layer. Multiplying the maximum weight layer and the high-frequency as new high-frequency. Finally, the fusion image is reconstructed by the low-frequency and the high-frequency. Experiments show that the proposed method can obtain more details from the image texture by retaining the significant features of the images. In addition, this method can effectively reduce artifacts and noise. The consistency in the objective evaluation and visual observation performs superior to the comparative algorithms. [ABSTRACT FROM AUTHOR]

Obvious spatiotemporal heterogeneity is a distinct characteristic of ecosystems in subtropical bays. To aid targeted management and ecological restoration in long and narrow semi-enclosed subtropical bays, we analyzed seasonal and regional differences in long-term changes (1980–2019) in the biomass and abundance of large mesozooplankton (LMZ; >505 µm) in Xiangshan Bay, Zhejiang, China. We found spatiotemporal heterogeneity in the historical changes of LMZ. Significant negative trends in LMZ biomass were found in the inner and middle bay during the warm season (summer and autumn), when the nutrient concentration (especially dissolved inorganic nitrogen) and temperature increased simultaneously. Nutrient changes in Xiangshan Bay began in the late 1980s or early 1990s, coinciding with large-scale fish cage development. A rapid decline in LMZ biomass occurred after 2005 when power plants commenced operation, accelerating the warming trend. Therefore, the joint stress of eutrophication and warming likely precipitated the decline in LMZ biomass. Conversely, a significant increase in LMZ biomass was found in the outer bay in spring. This trend was consistent with the trend of LMZ biomass near the Changjiang (Yangtze) River estuary, which indicates that the pelagic ecosystem in the outer bay was affected by water from the Changjiang River estuary during spring. Based on our results, ecosystem management and restoration in semi-enclosed subtropical bays should focus on internal waters, which have a poor capacity for water exchange. For Xiangshan Bay, the changes in the Changjiang River estuary ecosystem during the cold season (winter and spring) should also be considered. [ABSTRACT FROM AUTHOR]

Conspecific seagrass living in differing environments may develop different root system acclimation patterns. We applied X-ray computed tomography (CT) for imaging and quantifying roots systems of Zostera japonica collected from typical oligotrophic and eutrophic sediments in two coastal sites of northern China, and determined sediment physicochemical properties that might influence root system morphology, density, and distribution. The trophic status of sediments had little influence on the Z. japonica root length, and diameters of root and rhizome. However, Z. japonica in oligotrophic sediment developed the root system with longer rhizome node, deeper rhizome distribution, and larger allocation to below-ground tissues in order to acquire more nutrients and relieve the N deficiency. And the lower root and rhizome densities of Z. japonica in eutrophic sediment were mainly caused by fewer shoots and shorter longevity, which was resulted from the more serious sulfide inhibition. Our results systematically revealed the effect of sediment trophic status on the phenotypic plasticity, quantity, and distribution of Z. japonica root system, and demonstrated the feasibly of X-ray CT in seagrass root system research. [ABSTRACT FROM AUTHOR]

Remdesivir is a nucleotide analog prodrug that has received much attention since the outbreak of the COVID-19 pandemic in December 2019. GS-441524 (Nuc) is the active metabolite of remdesivir and plays a pivotal role in the clinical treatment of COVID-19. Here, a robust HPLC-MS/MS method was developed to determine Nuc concentrations in rat plasma samples after a one-step protein precipitation process. Chromatographic separation was accomplished on Waters XBrige C18 column (50 × 2.1 mm, 3.5 μm) under gradient elution conditions. Multiple reaction monitoring transitions in electrospray positive ion mode were m/z 292.2 → 163.2 for Nuc and 237.1 → 194.1 for the internal standard (carbamazepine). The quantitative analysis method was fully validated in line with the United States Food and Drug Administration guidelines. The linearity, accuracy and precision, matrix effect, recovery, and stability results met the requirements of the guidelines. Uncertainty of measurement and incurred sample reanalysis were analyzed to further ensure the robustness and reproducibility of the method. This optimized method was successfully applied in a rat pharmacokinetics study of remdesivir (intravenously administration, 5 mg kg−1). The method can act as a basis for further pharmacokinetic and clinical efficacy investigations in patients with COVID-19. [ABSTRACT FROM AUTHOR]

Inactivated foot-and-mouth disease virus (FMDV) vaccines have been used widely to control foot-and-mouth disease (FMD). However, the virions (146S) of this virus are easily dissociated into pentamer subunits (12S), which limits the immune protective efficacy of inactivated vaccines when the temperature is higher than 30 °C. A cold-chain system can maintain the quality of the vaccines, but such systems are usually not reliable in limited-resource settings. Thus, it is imperative to improve the thermostability of vaccine strains to guarantee the quality of the vaccines. In this study, four recombinant FMDV strains containing single or multiple amino acid substitutions in the structural proteins were rescued using a previously constructed FMDV type O full-length infectious clone (pO/DY-VP1). We found that single or multiple amino acid substitutions in the structural proteins affected viral replication to different degrees. Furthermore, the heat and acid stability of the recombinant viruses was significantly increased when compared with the parental virus. Three thermally stable recombinant viruses (rHN/DY-VP1Y2098F, rHN/DY-VP1V2090A-S2093H, and rHN/DY-VP1V2090A-S2093H-Y2098F) were prepared as inactivated vaccines to immunize pigs. Blood samples were collected every week to prepare sera, and a virus neutralization test showed that the substitutions S2093H and Y2098F, separately or in combination, did not affect the immunogenicity of the virus, but the Y2098F mutation increased the thermostability significantly (p < 0.05). Therefore, the rHN/DY-VP1Y2098F mutant should be considered for use in future vaccines. [ABSTRACT FROM AUTHOR]

Susceptibility to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the risk of mortality among people living with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) (PLWHA) is largely unknown. PLWHA are unique due to their altered immune system from their history of chronic HIV infection and their use of antiretroviral therapy, some of which have been used experimentally to treat coronavirus disease 2019 (COVID-19). Therefore, we conducted a systematic review and meta-analysis to assess the epidemiology of SARS-COV-2/HIV coinfection and estimate associated mortality from COVID-19 (Prospero Registration ID: CRD42020187980). PubMed, SCOPUS, OVID and Cochrane Library databases, and medRxiv preprint repositories were searched from January 1, 2020, to December 12, 2020. Data were extracted from studies reporting COVID-19 attack and mortality rates in PLWHA compared to their HIV-negative counterparts. Pooled attack and mortality risks were quantified using random-effects models. We identified 22 studies that included 20,982,498 participants across North America, Africa, Europe, and Asia. The median age was 56 years, and 50% were male. HIV-positive persons had a significantly higher risk of SARS-CoV-2 infection [risk ratio (RR) 1.24, 95% CI 1.05–1.46)] and mortality from COVID-19 (RR 1.78, 95% CI 1.21–2.60) than HIV-negative individuals. The beneficial effects of tenofovir and protease-inhibitors in reducing the risk of SARS-CoV-2 infection and death from COVID-19 in PLWHA remain inconclusive. HIV remains a significant risk factor for acquiring SARS-CoV-2 infection and is associated with a higher risk of mortality from COVID-19. In support of the current Centers for Disease Control and Prevention (CDC) guidelines, persons with HIV need priority consideration for the SARS-CoV-2 vaccine. [ABSTRACT FROM AUTHOR]

Sulfate-reducing bacteria (SRB) are ubiquitous anaerobic microorganisms that play significant roles in the global biogeochemical cycle. Coastal wetlands, one of the major habitats of SRB, exhibit high sulfate-reducing activity and thus play significant roles in organic carbon remineralization, benthic geochemical action, and plant-microbe interactions. Recent studies have provided credible evidence that the functional rather than the taxonomic composition of microbes responds more closely to environmental factors. Therefore, in this study, functional gene prediction based on PacBio single molecular real-time sequencing of 16S rDNA was applied to determine the sulfate-reducing and organic substrate-decomposing activities of SRB in the rhizospheres of two typical coastal wetland plants in North and South China: Zostera japonica and Scirpus mariqueter. To this end, some physicochemical characteristics of the sediments as well as the phylogenetic structure, community composition, diversity, and proportions of several functional genes of the SRB in the two plant rhizospheres were analyzed. The Z. japonica meadow had a higher dissimilatory sulfate reduction capability than the S. mariqueter-comprising saltmarsh, owing to its larger proportion of SRB in the microbial community, larger proportions of functional genes involved in dissimilatory sulfate reduction, and the stronger ability of the SRB to degrade organic substrates completely. This study confirmed the feasibility of applying microbial community function prediction in research on the metabolic features of SRB, which will be helpful for gaining new knowledge of the biogeochemical and ecological roles of these bacteria in coastal wetlands. [ABSTRACT FROM AUTHOR]

To determine the factors controlling variations in the biomass (B), abundance (A), and mean individual biomass (B/A) of mesozooplankton in a subtropical eutrophic bay, a random forest model was used to analyze the effects of physicochemical factors and phytoplankton biomass, size, and taxonomic composition on the variations in B, A, and B/A of mesozooplankton using 100 samples from all four seasons of 2015 in Xiangshan Bay, China. Variations in the B and A of mesozooplankton were related to both physicochemical and phytoplankton factors, while physicochemical factors were the best predictors of variation in the B/A of mesozooplankton. Phytoplankton biomass was too high to limit mesozooplankton growth, leading to a weak relationship between mesozooplankton and phytoplankton biomasses. The mesozooplankton were sensitive to temperature, and an increase in temperature increased mainly the number of small mesozooplankton. Temperature, suspended solids (SS), and nutrients indirectly affected the A and B/A of mesozooplankton by changing the abundance, size, and species composition of phytoplankton. Size mismatches between phytoplankton and mesozooplankton sometimes occur with changes in the physicochemical environment, which might reduce trophic transfer efficiency in planktonic ecosystems. This study implies that we should pay attention to the impact of warming on the planktonic ecosystem in the context of global warming, especially in subtropical bays with intensive human activity. [ABSTRACT FROM AUTHOR]

Watermarking plays an import role in digital copyright protection. It enables copyright owners to embed invisible watermarks within copies of data before distribution. However, most existing watermarking algorithms for 2D vector maps use either spatial domain methods, e.g., the Least Significant Bit or frequency domain methods, e.g., discrete Fourier transform (DFT), and very few algorithms combine the two domains. In order to improve the robustness of watermarks to against more common attacks, a novel algorithm using a combination of spatial and frequency domains is presented. Both the spatial domain and the frequency domain can be used for watermark embedding. Obviously, the advantages of each method are retained and the disadvantages of each method are offset by complementation. The watermark was also shuffled before embedding. A one-way hash function was used to map the watermark and 2D vector map. By using two different methods, one part of the watermark was embedded into the spatial domain first and another part of the watermark was embedded into the DFT domain. Additionally, the watermark was embedded multiple times. No original map data are required for the watermark extraction procedure. Analysis shows that the distortions of the watermarked data are extremely small, and the algorithm is more robust than methods using a single domain. It can resist the most common attacks, such as vertex insertion and removal, cropping, compression, reordering, and data format conversion attacks. It is also robust against rotation scaling and translation attacks. [ABSTRACT FROM AUTHOR]

The effect of nitroguanidine (NQ) content on thermal decomposition of nitroguanidine propellants was studied using three nitroguanidine propellants with different NQ contents (10%, 30% and 47%) and one double-base propellant. The thermal decomposition was investigated by high-pressure differential scanning calorimetry. Results show that heat flow curves of the four tested formulations all had only one exothermic peak, and as the heating rate increased, both the peak temperature and the decomposition heat increased. Calculation of thermal decomposition kinetics of the propellants was performed using multiple-temperature programs. Increased NQ contents changed the mechanism of thermal decomposition of the propellant. The reaction mechanism is chemical reaction for the double-base propellant and the 47%-NQ propellant, phase boundary reaction for the 30%-NQ propellant and nucleation and growth for the 10%-NQ propellant. The thermodynamic parameters indicate that, as the NQ content increases, the critical temperature (Tbe) of thermal explosion of the propellants increases, which leads to higher thermal stability for the 30%-NQ content. Thus, among the three nitroguanidine propellants, the 30%-NQ propellant has a lower thermal stability. [ABSTRACT FROM AUTHOR]

A Christmas tree is a key wellhead device consisting of valves and fittings used for controlling oil and gas well fluid. Generally, various combinations are applied on Christmas tree to meet the requirement of specific working conditions. In present work, fracture of a four-way flange of a KQ65 wellhead Christmas tree was investigated through mechanical properties testing, microstructure characterization and fractography analysis. It is revealed that the four-way flange possesses very low impact toughness, and its CVN impact energy was only 4 J at 243 K. Representative microstructure of the four-way flange consists of coarse polygonal ferrite and pearlite, and the size of pearlite cluster was up to 280 μm. Ferrite grains displayed networks along grain boundaries of pearlite colony. The brittle microstructure of the four-way flange was likely caused by inappropriate heat treatment process. In addition, fractography analysis showed that fracture crack initiated from the flange and four-way junction, where stress was concentrated and thus resulted in the dimensional and structural change of four-way flange. It is concluded that fracture failure of the KQ65 wellhead Christmas tree was caused by coupling effect of the brittle microstructure and the localized stress concentration. [ABSTRACT FROM AUTHOR]

A detailed understanding of the composition, buffering capacity, surface charge property, and metals leaching behavior of bauxite residue is the key to improved management, both in reducing the environmental impact and using the material as an industrial by-product for other applications. In this study, physical, chemical, and surface charge properties of bauxite residue derived from a combined process were investigated. Results indicated that the main alkaline solids in bauxite residue were katoite, sodalite, and calcite. These minerals also lead to a higher acid neutralizing capacity of bauxite residue. Acid neutralizing capacity (ANC) to pH 7.0 of this residue is about 0.9 mol H+/kg solid. Meanwhile, the Fe-, Al-, and Si-containing minerals in bauxite residue resulted in an active surface; The isoelectric point (IEP) and point of zero charge (PZC) were 7.88 and 7.65, respectively. This also leads to a fact that most of the metals in bauxite residue were adsorbed by these surface charged solids, which makes the metals not readily move under natural or even moderately acidic conditions. The leaching behavior of metals as a function of pH indicated that the metals in bauxite residue present low release concentrations (pH > 3). [ABSTRACT FROM AUTHOR]

The goal of this paper is to propose a novel approach for determining the weights of decision makers (DMs) in group settings with a rough set group method, in which each decision maker’s decision matrix is in interval numbers. In this paper, we first build a lower rough group decision (LRGD) and an upper rough group decision (URGD) from a rough group decision. Then, we define the average matrix of LRGD as a Lower positive ideal solution (Lower PIS), and the average matrix of URGD as an Upper positive ideal solution (Upper PIS) based on the Technique for Order Preference by Similarity to Ideal Solution method. Next, the average matrix of the Lower PIS and Upper PIS is regarded as the positive ideal solution (PIS), and the farthest distance from the PIS is regarded as the negative ideal solution (NIS). After that, each DM’s weight is derived from the distances from the DM’s decision to the PIS and NIS. Comparisons with existing methods are also made. Finally, an example of air quality evaluation is provided to clarify the availability of the proposed method. [ABSTRACT FROM AUTHOR]

Bauxite residue neutralization is intended to open opportunities for revegetation and reuse of the residue. Ferrous sulfate (FS) and nitrohumic acid (NA) were two kinds of materials studied for pH reduction of the residue from 10.6 to 8.3 and 8.1, respectively. The effects of FS and NA on the leaching of metals from a combined bauxite residue were investigated by using sequential and multiple extraction procedures. Neutralization with FS and NA restricted the leaching of Al, V, and Pb from the residue but promoted the leaching of Fe, Cu, Mn, and Ni, consistent with the changes in the potentially mobile fractions. With the exceptions of Pb and Ni, leaching of metals increased during a 10-day extraction period. However, the maximum leaching of Al, V, Pb, Fe, Cu, Mn, and Ni from neutralized bauxite residue were 0.46 mg/L, 59.3, 12.9, 167, 95.3, 15.5, and 14.5 μg/L, respectively, which were under the corresponding limits in the National Standard (GB/T 14848-93). Although it is necessary to consider the continued leaching of metals during neutralization, both maximum and accumulation leaching concentrations of metals from a combined bauxite residue were too low to pose a potential environmental risk. [ABSTRACT FROM AUTHOR]

Aim: Ultrasound-guided biopsy technique with the large-core needle has widely been applied in the diagnosis of adult abdominopelvic cavity, thyroid, and neck tumors. There are few reports on ultrasound-guided biopsy using large-core needle in pediatric abdominopelvic cavity tumors. This study was to evaluate the ultrasound features and the diagnostic value of ultrasound-guided core needle biopsy for pediatric neuroblastic tumors.Methods: The pediatric patients with neuroblastic tumor that underwent ultrasound examination and ultrasound-guided core needle biopsy from January 2009 to November 2015 were reviewed. A minimum of two cores in each case was obtained. The biopsy results were confirmed by subsequent surgical histopathology. The ultrasound features and the diagnostic accuracy of ultrasound-guided core needle biopsy were evaluated.Results: Eighty-three patients were enrolled into the study. Conventional ultrasound examination showed irregular hypoechoic or mixed echo masses and calcification and liquefied necrosis. The diagnostic accuracy of ultrasound-guided core needle biopsy was 96.4% (80/83). Three cases were misdiagnosed because of inadequate tissue sample. No serious complication, infection, or needle track seeding occurred.Conclusions: Ultrasound-guided core needle biopsy seems to be an accurate, minimally invasive, and safe diagnostic method of pediatric neuroblastic tumor. [ABSTRACT FROM AUTHOR]

China's insistence on the non-interference principle has been increasingly inconsistent. While China's concern with sovereignty, regime security, and legitimacy, as well as its developing country identity, have pushed it to continue its insistence on the principle of non-interference, China's further adaptation to the international system, increasing engagement in international institutions, and new identity as a responsible power have led China to drag its feet on the same principle. To reconcile these competing forces, China has to make concessions, namely, setting preconditions to legitimize intervention, designing a sovereignty-first solution, and/or complementing the non-interference principle with alternative principles. China's application of the non-interference principle has thus been made contingent. It is more inflexible at one end of a spectrum and more flexible at the other end, with China's foreign policies shifting back and forth between them. [ABSTRACT FROM AUTHOR]

Concentrations of eight heavy metals (arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), and zinc (Zn)) were measured in 92 topsoil samples collected from agricultural areas in Daye City to (1) assess the distribution of these heavy metals, (2) discriminate natural and anthropic contributions, and (3) identify possible sources of pollution. Mean concentrations of As, Cd, Cu, and Zn in the investigated soils were 23.8, 1.41, 105, and 159 mg kg, respectively. These values were higher, in some cases by several orders of magnitude, than their corresponding background values. Estimated ecological risks, based on contamination factors and potential ecological risk indexes, were mostly low, but were considerable for As and Cd. A range of basic and multivariate statistical analyses (Pearson's correlation analysis, hierarchical cluster analysis, and principal component analysis) clearly revealed two distinct metal groups, comprising As/Cd/Cu/Zn and Cr/Ni/Hg/Pb, whose concentrations were closely associated with the distribution and pollution characteristics of industries in and around the city. Results demonstrated that As/Cd/Cu/Zn were indicators of anthropic pollution, while Cr/Hg/Ni/Pb were from parent materials. Maps of pollutant distribution compiled for the entire arable area further indicated that non-ferrous metal smelting and mining is the main source of diffuse pollution, and also showed the contribution of point source pollution to metal concentrations in agricultural topsoil. Results of this study will be useful for planning, risk assessment, and decision making by environmental managers in this region. [ABSTRACT FROM AUTHOR]

Growth factors (GFs) are very critical in stem cell differentiation and tissue regeneration. Therefore GF delivery carriers have been a major subject in tissue engineering research. In this study, we prepare and optimize core-shell microcapsules (C-S MCs) for dual GF delivery. The C-S MCs, composed of an alginate shell and poly(lactic-co-glycolic) acid (PLGA) core, are fabricated using an electrodropping method via custom-made coaxial needles. They are 198±38 µm in diameter with an average core size of 90±13 µm, and they are fabricated using an alginate concentration of 1% (w/v), an electrical voltage of 11 kV, and an inner syringe flow rate of 50 µL/min. Using this platform, dual GFs, bone morphogenetic protein (BMP-2) and vascular endothelial growth factor (VEGF) are encapsulated in the alginate shell and PLGA core, respectively. In vitro release tests of dual GF-loaded C-S MCs reveal early release of BMP-2, followed by VEGF on a temporal release profile of 28 days. In vitro study of the dual GF-loaded MCs demonstrates their osteogenic activity with preosteoblasts; osteogenic markers (osteocalcin and type I collagen) are upregulated and both calcium content and alkaline phosphatase (ALP) activity also increased. In addition, C-S MCs combined with collagen and preosteoblasts were subcutaneously transplanted to the dorsal region of nude mice for 3 weeks. Analysis of the retrieved constructs exhibits that both osteogenesis and angiogenesis were more active in the group containing dual GF-loaded MCs, along with deep penetration of blood vessels inside the construct, compared to blank MCs or single GF (BMP-2)-loaded MCs. This study proposes a dual GF delivery carrier using C-S MCs and demonstrates the feasibility of C-S MCs in the induction of osteogenesis and angiogenesis. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effect of large granulated lactose carrier particle systems on aerosol performance of dry powder inhaler formulations. Granulated lactose carriers with average sizes ranging from 200 to 1,000 μm were prepared and subsequently fractionated into separate narrow size powders. The fractionated granulated lactose (GL) samples were characterized in terms of size, specific surface area, surface roughness, morphology, density, flowability, and solid-state. The in vitro aerosolization performance was performed on the different size fractions of GL samples from a commercial inhaler device (Aerolizer®) with a model formulation (2% w/w salbutamol sulfate). The cascade impaction parameters employed were 60 or 90 L/min with standard (aperture size, 0.6 mm) or modified piercing holes (aperture size, 1.2 mm) of the inhaler loaded capsules. It was shown that the largest size fraction formulation (850-1000 μm) had a slight improvement in the fine particle fraction (FPF) compared to immediately preceding size fractions, explained by a smaller adhesive force between drug and carrier. Compared to commercial piercing holes, enlarged piercing holes generated a slight decreasing trend of FPF as the lactose powder sizes increased from 200-250 μm to 600-850 μm, perhaps due to the reduced detachment force by flow forces. The size, surface roughness, density, and flowability of lactose carrier as well as device design all contributed to the aerosol dispersion performance of granulated lactose-based adhesive mixtures. It was concluded that poorer or enhanced redispersion performance is not an inherent property to the significantly large size of granulated lactose carriers as previously contended. [ABSTRACT FROM AUTHOR]

Purpose: Plm60-s is a pegylated liposomal mitoxantrone formulation, in which mitoxantrone was loaded into small unilamellar vesicles (~60 nm) made from solid lipid membrane. This two-arm, dose-escalating phase I study was designed to determine safety and pharmacokinetics of plm60-s, and to compare with those of conventional mitoxantrone injection (c-MI). Methods: Patients received an intravenous infusion of plm60-s at 6, 10, 12, 14, 16 and 18 mg/m every 4 weeks. Three or 6 patients were in each group of dose level. If more than one third patients of a group experienced dose-limiting toxicity, dose climbing will stop. The control group of 3 patients received c-MI at 10 mg/m every 28 days. Samples for pharmacokinetic studies were collected. The analysis of the safety and tolerability was done according to the record and laboratory examination, etc. Results: Twenty patients were enrolled. One grade 3 leukocytopenia occurred in plm60-s groups. Plm60-s was safer than c-MI at the same dose of 10 mg/m. Two complete responses and one partial response occurred in plm60-s group. In plasma, plm60-s exhibited sustained release of the content, resulting in the reduced peak concentrations and enhanced AUC of released MIT. Total mitoxantrone was linearly cleared, and mitoxantrone was predominantly in the liposomal encapsulation form. Repeated administration of plm60-s did not affect the clearance kinetics. Conclusions: At a dose of up to 18 mg/m, plm60-s could be well tolerated and potential efficacy could be observed. The pharmacokinetic profile of plm60-s was remarkably altered. Further investigations are in progression. [ABSTRACT FROM AUTHOR]

Simotinib is a novel oral small-molecule tyrosine kinase inhibitor that has demonstrated equal or superior antineoplastic activities to erlotinib in preclinical studies. In support of a clinical pharmacokinetic study, a sensitive and accurate liquid chromatography (LC) method with mass spectrometry detection using multiple reaction monitoring (MRM) in positive ion mode was developed and validated for the quantification of simotinib in human plasma. The sample preparation procedure involved a simple protein precipitation with methanol. Erlotinib was used as the internal standard. The optimal chromatographic behavior was achieved on a Zorbax SB-C8 column (2.1 mm × 100 mm, 3.5 μm) using a mixture of 0.1 % formic acid with 10 mM ammonium formate/methanol (20:80, v/v) as the mobile phase. The total LC analysis time per injection was 4 min with a flow rate of 0.2 mL/min. The recovery was greater than 90 % and no significant matrix effect was observed. The assay was validated over the concentration range of 1-1,000 ng/mL. The intra- and interday precision and accuracy of the quality control samples at low, medium, and high concentration levels showed at most 9.4 % relative standard deviation (RSD) and −7.4 to 7.4 % relative errors (RE). Assay selectivity, freeze/thaw stability, storage stability, and dilution effects were also assessed. The method is now used to support clinical pharmacokinetic studies in patients with non-small cell lung cancer (NSCLC) after oral administration of simotinib. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The distributions of N utilizing bacteria (denitrifying bacteria and ammonifying bacteria), P utilizing bacteria (organic phosphobacteria and inorganic phosphobacteria) and heterotrophic bacteria in the Changjiang Estuary, and the roles of main environmental factors in distributing bacteria, are explored with observations from two cruises in June and August 2006. Comparisons between the two important periods of initial hypoxia phase (June) and developed hypoxia phase (August) show differences in both bacterial distributions and the associated main environmental factors. First, the primary group of ammonifying bacteria has larger magnitude with spatial maximum value in the hypoxic stations related to sediment in August. The phosphobacterial abundance and detection rates in August are much lower than those in June, but the denitrifying bacterial abundance becomes greater in August. However, the difference of heterotrophic bacterial abundance between June and August is not obvious. Second, main environmental factors influencing bacteria vary from initial hypoxia phase to developed hypoxia phase. Two parameters (salinity and NO) in surface water and five environmental parameters (pH, salinity, PO, NO and temperature) in bottom water and surface sediment play major roles in the bacterial abundance in June, while different parameter combinations (salinity and PO) in surface water and different parameter combinations (DO, DOC, NO, PO and pH) in bottom water and surface sediment play major roles in August. Moreover, the bottom bacteria distributions in area south of 31°N are related to the position of the Taiwan Warm Current in June. The bacterial abundance and distribution may respond to the environmental change in the hypoxia processes of initial phase and developed phase. During the hypoxia processes, the whole structure of bacterial functional groups probably turns to different states, causing the recycling of nutrient regeneration and aggravating hypoxia regionally. [ABSTRACT FROM AUTHOR]

With the rapid development of economy and increase of population in the drainage areas, the nutrient loading has increased dramatically in the Changjiang estuary and adjacent coastal waters. To properly assess the impact of nutrient enrichment on phytoplankton community, seasonal microcosm experiments were conducted during August 2010-July 2011 in the coastal waters of Zhejiang Province. The results of the present study indicated that the chl a concentration, cell abundance, diversity indices, species composition and community succession of the phytoplankton varied significantly with different N/P ratios and seasons. Higher growth was observed in the 64:1 (spring), 32:1 (summer), 16:1 (autumn) and 128:1, 256:1 (winter) treatments, respectively. The values of Shannon-Wiener index ( H′) and Pielou evenness index ( J) were lower in the 8:1 and 16:1 treatments in autumn test, while H′ value was higher in the 128:1 and 8:1 treatments in winter test. A definite community succession order from diatoms to dinoflagellates was observed in the autumn and winter tests, while the diatoms dominated the community throughout the culture in the spring and summer tests. [ABSTRACT FROM AUTHOR]

In this study, a vertical submerged biofilm reactor was applied to investigate autotrophic partial nitrification/denitrification and simultaneous sulfide removal by using synthetic wastewater. The appropriate influent ratios of ammonia and sulfide needed to achieve partial autotrophic nitrification and denitrification were evaluated with influent ammonium nitrogen ranging from 54.6 to 129.8 mg L and sulfide concentrations ranging from 52.7 to 412.4 mg S L. The results demonstrated that the working parameter was more stable when the sulfur/nitrogen ratio was set at 3:2, which yielded the maximum sulfur conversion. Batch experiments with different phosphate concentrations proved that a suitable phosphate buffer solution to control pH values could improve synchronous desulfurization denitrification process performance. [ABSTRACT FROM AUTHOR]

To analyze foot-and-mouth disease virus tropism and host range with respect to the integrin receptor, we cloned cDNAs encoding the integrin αν, β1, β3, β6 and β8 subunits from Chinese yellow cattle and Gansu black swine and carried out comparative analysis of their molecular characteristics. The lengths of the mature proteins and the functional domains of the four integrin β subunits were the same between bovine and swine; however, the number of putative N-linked glycosylation sites and cysteine residues and their arrangement varied. Homology analysis of the nucleotide and amino acid sequences showed that FMDV integrin receptors of Chinese yellow cattle and Gansu black swine are highly conserved. Phylogenetic analysis showed that all FMDV integrin receptor subunits of cattle and swine are clustered into the Artiodactyla group; however, Chinese yellow cattle are phylogenetically closer to sheep than to Gansu black swine. We postulate that the host tropism of FMDV may, in part, be related to the divergence of integrin subunits among different species. [ABSTRACT FROM AUTHOR]

Poly(1-amino-5-chloroanthraquinone) (PACA) was firstly synthesized by a chemically oxidative interfacial polymerization. The PACA has been developed as a fluorescent sensor for the determination of Fe(III) in semi-aqueous solution at pH 7.0. The sensor exhibited remarkably high sensitivity toward Fe since the fluorescence of the polymer could be significantly quenched even though trace Fe was added. The sensor showed a linear fluorescence emission response over a wide concentration range from 1.0 × 10 to 1.0 × 10 M, with an ultra-low detection limit of 2.0 × 10 M. The quenching of the fluorescence was found to be static one due to the formation of non-fluorescent complex in the ground state. [ABSTRACT FROM AUTHOR]

The present study was to evaluate the value of miRNA-30a in plasma as potential tumor marker in detecting breast cancer (BC). Using a novel approach to extract miRNA-30a from the plasma followed by real-time quantitative polymerase chain reaction (RQ-PCR) analysis, levels of miRNA-30a were quantified in plasma specimens of 100 BCs and 64 age-matched and disease-free healthy controls (HC). And we compared the diagnostic value of plasma miRNA-30a with conventional circulating tumor markers CA153 and CEA. The median levels of miRNA-30a were significantly lower in preoperative BC than those in HC ( P < 0.001). The levels of CEA and CA153 were all significantly higher in preoperative BC compared with those in HC ( P = 0.008 and P = 0.001, respectively), and only the level of CA153 decreased in postoperative BC compared with preoperative BC ( P = 0.015). ROC analysis showed the sensitivity and specificity of miRNA-30a for BC diagnosis at 74.0 and 65.6 %, respectively, whereas the sensitivities of CEA and CA153 were 12.0 and 14.0 %, respectively. The status of ER and triple-negative BC was significantly associated with miRNA-30a level ( P = 0.007 and P = 0.005, respectively). And no other clinicopathological features were found to had significant difference. Our findings suggest that plasma miRNA-30a decreased in patients with BC and has great potential to use as novel biomarkers for BC diagnosis. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome (PRRS) is an economically important swine disease affecting swine worldwide. Northwest China has a sparse pig population and there is no comprehensive information currently available on PRRSV infection. In this study, we analyzed the epidemiological features and genetic diversity of PRRSV from this region. 322 field-isolated tissues or serum samples were collected from aborted pig fetuses or pigs with respiratory disease from 15 herds, twice over a period of 2 years. PRRSV infection was determined and virus strains were classified by the sequencing of GP5. We found that 35.9 % of the animals were PRRSV-positive, and the average prevalence in 2007-2008 and 2009-2010 was 46.5 and 29.3 %, respectively. To further investigate the genetic divergence of PRRSV samples collected from 2007 to 2010, 32 strains were isolated for GP5 sequencing and analysis, and phylogenetic trees were created based on GP5 amino acid sequences. All PRRSVs were of the North American genotype and belonged to the highly pathogenic HP-PRRSV subgenotype. Isolates from the Xinjiang province formed a tightly clustered branch and were closely related to an evolutionary intermediate subgroup isolate. Virus sequences from 2007 to 2008 were compared with those from 2009 to 2010 from the same herd. New mutations were found in isolates after 2009 and focused on nucleotides in the GP5 antibody decoy epitope. PRRSV strains in Northwest China from 2007 to 2010 were similar to those from other regions of China, with some regional characteristics. These results contribute to the knowledge of PRRSV epidemiology in China. [ABSTRACT FROM AUTHOR]

In this work, through inclusion complexation between cyclodextrin (CD) host and ferrocene (Fc) guest, a monomer with double bond was incorporated to the surface of CdS quantum dot (QD). The obtained supra-structure could act as a supra-crosslink (Fc-SCL) in its copolymerizing with N,N-dimethylacrylamide (DMA) leading to a hybrid supramolecular hydrogel (Fc-Gel). Fc-SCL inherited satisfactory electrochemical activity from Fc. When the weight percentage of Fc-SCL in Fc-Gel was increased, an apparent increase of elastic modulus ( G′) was observed. Furthermore, Fc-Gel also exhibited good fluorescent properties. It was also demonstrated that the inclusion complexation of CD and Fc played a crucial role in constructing the hydrogel; therefore, this Fc-Gel was an organic-inorganic hybrid hydrogel induced by supramolecular interaction. [ABSTRACT FROM AUTHOR]

The Chinese medical ethics committee and the ethical review system have made the following achievements: (1) enabled the institutionalization of medical ethics, (2) carried out the ethics review of Chinese medicine (CM) and integrative medicine extensively, (3) trained a large number of ethical professionals, (4) supported and protected the interests of patients and subjects, and (5) ensured the correct direction of biological research and provided ethical defense for the publication of its results. However, at the same time, they are also faced with some new problems and difficulties that need to be resolved in the following ways: (1) to refine the relevant rules of ethical review, (2) to develop the relevant standards of the CM and integrative medicine ethical review, (3) to enhance the independence and authority of ethics committee, (4) to emphasize innovation and to discover and solve new problems, and (5) to increase international exchanges and improve relevant research. [ABSTRACT FROM AUTHOR]