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Frequent low visibility, haze and fog events were found in the North China Plain (NCP). Data throughout the NCP during the past 30 years were examined to determine the horizontal distribution and decadal trends of low visibility, haze and fog events. The impact of meteorological factors such as wind and relative humidity (RH) on those events was investigated. Results reveal distinct distributions of haze and fog days, due to their different formation mechanisms. Low visibility, haze and fog days all display increasing trends of before 1995, a steady stage during the period 1995–2003 and a drastically drop thereafter. All three events occurred most frequently during the heating season. Benefiting from emission control measures, haze and fog both show decreasing trends in winter during the past 3 decades, while summertime haze displays continuous increasing trends. The distribution of wind speed and wind direction as well as the topography within the NCP has determinative impacts on the distribution of haze and fog. Weakened south-easterly winds in the southern part of the NCP have resulted in high pollutant concentrations and frequent haze events along the foot of the Taihang Mountains. The orographically generated boundary layer wind convergence line in the central area of the southern NCP is responsible for the frequent fog events in this region. Wind speed has been decreasing throughout the entire southern NCP, resulting in more stable atmospheric conditions and weaker dispersion abilities, calling for harder efforts to control emissions to prevent haze events. Haze events are strongly influenced by the ambient RH. RH values associated with haze days are evidently increasing, suggesting that an increasing fraction of haze events are caused by the hygroscopic growth of aerosols, rather than simply by high aerosol loadings.

This study is aimed at investigating the mechanism by which a reactive material enhances the energy output of a composite charge consisting of an inner explosive, an intermediate non-detonating layer, and an outer explosive, which are widely used in tunable ammunition. Explosion experiments are conducted in two initiation modes. Using reactive Al/rubber significantly increases the fireball growth, shock wave velocity, and shock wave overpressure of the composite charge compared to using inert LiF/rubber. For simultaneous initiation, the increase is more obvious owing to the continuous exothermic reaction of the reactive layer. A composite charge with 40% (vol.) Al shows the highest difference in peak overpressure under the two initiation modes: 41.4%. A charge with 60% (vol.) Al ensures even lower shock wave and fireball velocities and peak overpressure than those of the 40% (vol.) Al charge, indicating that the excessive reactive Al content in the non-detonating layer inhibits the blast of the composite charge.

In this paper, a detailed investigation is conducted to analyze the relationships between the mechanical properties of recycled aggregate concrete (RAC). Based on a large number of experimental results published worldwide in literature from 1985 to 2004, an experimental database is developed with regard to the main mechanical properties of RAC. In particular, the relations between the compressive strength, the density, the splitting tensile strength, the flexural strength, and the elastic modulus are investigated and discussed in detail. It is found that the interrelationships between the mechanical properties of RAC could be quite different from those of normal concrete. Some improved new equations are proposed for the prediction of the relations between the mechanical properties of RAC based on the statistical regression analysis with the least squares method.[PUBLICATION ABSTRACT]

Adenosine-to-inosine (A-to-I) RNA editing is a neurodevelopmentally regulated epigenetic modification shown to modulate complex behavior in animals. Little is known about human A-to-I editing, but it is thought to constitute one of many molecular mechanisms connecting environmental stimuli and behavioral outputs. Thus, comprehensive exploration of A-to-I RNA editing in human brains may shed light on gene–environment interactions underlying complex behavior in health and disease. Synaptic function is a main target of A-to-I editing, which can selectively recode key amino acids in synaptic genes, directly altering synaptic strength and duration in response to environmental signals. Here, we performed a high-resolution survey of synaptic A-to-I RNA editing in a human population, and examined how it varies in autism, a neurodevelopmental disorder in which synaptic abnormalities are a common finding. Using ultra-deep (>1000 × ) sequencing, we quantified the levels of A-to-I editing of 10 synaptic genes in postmortem cerebella from 14 neurotypical and 11 autistic individuals. A high dynamic range of editing levels was detected across individuals and editing sites, from 99.6% to below detection limits. In most sites, the extreme ends of the population editing distributions were individuals with autism. Editing was correlated with isoform usage, clusters of correlated sites were identified, and differential editing patterns examined. Finally, a dysfunctional form of the editing enzyme adenosine deaminase acting on RNA B1 was found more commonly in postmortem cerebella from individuals with autism. These results provide a population-level, high-resolution view of A-to-I RNA editing in human cerebella and suggest that A-to-I editing of synaptic genes may be informative for assessing the epigenetic risk for autism.

An experimental study of the afterglow mode was performed with a third generation electron cyclotron resonance ion source, SECRAL-II (Superconducting ECR ion source with Advanced design in Lanzhou No. II), under double frequency heating. The experimental results show that intense pulsed beams of highly charged ions (e.g.,266eμAofXe12934+and169eμAofXe12938+) could be produced at high frequency (24+18GHz) and high power (∼8kW), even compared with the beam intensity records of SECRAL-II obtained in continuous wave (cw) mode at higher microwave frequency (28+18GHz) and higher power (∼10kW), the gain factor is also up to∼3. Meanwhile, it is found that the afterglow decay time in our study is much longer than that obtained with the second generation ECR ion sources typically operating at 10–18 GHz, and the corresponding peak duration is greater than 2 ms. This study provides a viable solution for heavy ion synchrotron accelerator complex such as High Intensity Heavy Ion Accelerator Facility project that requires intense pulsed beams of highly charged ions with long peak duration.

The purpose of this study was to test the mutant selection window (MSW) hypothesis in vitro and in vivo with Staphylococcus aureus exposed to fosfomycin. With the in vitro time–kill studies, S. aureus ATCC 29213 [with a minimal concentration that inhibits colony formation by 99 % (MIC 99 ) of 2.2 μg/mL and a mutant prevention concentration (MPC) of 57.6 μg/mL] lost fosfomycin susceptibility at antibiotic concentrations (2×, 4×, and 8× MIC) that are between the lower and upper boundaries of the MSW. In the tissue-cage model, S. aureus was exposed to fosfomycin pharmacokinetics at concentrations below the MIC 99 , between the MIC 99 and the MPC, and above the MPC, respectively. Changes in susceptibility and counts of total and resistant viable bacteria were monitored in tissue-cage fluid obtained daily. However, the selection of resistant mutants was not observed during antibacterial treatment and 48 h after the termination of fosfomycin treatment, regardless of the fosfomycin dosage. Besides, we found no differences between the in vitro-isolated mutant and its sensitive parental strain, which indicates the absence of fitness cost of fosfomycin resistance in S. aureus ATCC 29213. These findings demonstrate that agar plate determinations do not fit the MSW for fosfomycin treatment of rabbits infected with S. aureus ATCC 29213; therefore, the existence of the window must be demonstrated not only in vitro but also in vivo. Further research is needed on the exact mechanism of resistance.

Abstract In arthropods, the moult-inhibiting hormone (MIH), the ecdysone receptor (EcR), and the retinoid X receptor (RXR) are key regulators in moulting. In the present study, the full-length cDNAs of the MIH, EcR2, and RXR3 genes from the red swamp crayfish, Procambarus clarkii (Girard, 1852) (denoted as PcMIH, PcEcR2, and PcRXR3) were cloned. Tissue-specific and moult stage-specific mRNA expression patterns of these genes were detected by real-time quantitative polymerase chain reaction. PcMIH was detected only in the eyestalk, whereas PcEcR2 and PcRXR3 mRNA were expressed in all tissues tested. The highest levels of PcEcR2 and PcRXR3 were detected in the gill and hepatopancreas. Expression of PcMIH mRNA in the eyestalk increased from postmoult to peak in intermoult and then decreased in premoult. Expression of PcEcR2 mRNA in the eyestalk, hepatopancreas, and muscle increased from postmoult to peak in early premoult and then decreased. However, expression of PcEcR2 mRNA in the gill increased from postmoult to reach a maximum in intermoult and then decreased in premoult. Expression of PcRXR3 mRNA also fluctuated in the eyestalk, hepatopancreas, muscle, and gill, with a decrease from postmoult to late premoult. Expression of PcEcR2 and PcRXR3 mRNA increased relative to the control in the hepatopancreas and gill after unilateral and bilateral eyestalk ablation, which suggested that PcMIH can inhibit their mRNA expression. Double-stranded RNA-mediated RNA interference of PcRXR3 caused different changes in mRNA expression of these genes in different tissues and resulted in decreased expression of PcEcR2 mRNA, which suggested a collaborative relationship between PcEcR2 and PcRXR3.

Introduction: This study aimed to develop the Healthy Eating Report Card for Pre-school Children in Hong Kong for evaluating the prevalence of healthy eating behaviours and favourable family home food environments (FHFEs) among pre-school children in Hong Kong.Methods: In this cross-sectional study, 538 parent-child dyads from eight kindergartens in Hong Kong were recruited. Parents or guardians completed a questionnaire comprising Report Card items. The Report Card included two indicators of Children’s Eating Behaviours (ie, Children’s Dietary Patterns and Children’s Mealtime Behaviours) and three indicators of FHFEs (ie, Parental Food Choices and Preparation, Avoidance of Unhealthy Foods, and Family Mealtime Environments). Each indicator and its specific items were assigned a letter grade representing the percentage of participants achieving the predefined benchmarks. The grades were defined as A (≥80%, Excellent); B (60%-79%, Good); C (40%-59%, Fair); D (20%-39%, Poor); and F (<20%, Very poor). Plus (+) and minus (-) signs were used to indicate the upper or lower 5% of each grade.Results: Overall, Children’s Eating Behaviours were classified as Fair (average grade of ‘C’), whereas FHFEs were classified as Good (average grade of ‘B’). The sub-grades ranged from ‘C’ to ‘A-’, as follows: Children’s Dietary Patterns, ‘C+’; Children’s Mealtime Behaviours, ‘C’; Parental Food Choices and Preparation, ‘C+’; Avoidance of Unhealthy Foods, ‘B’; and Family Mealtime Environments, ‘A-’.Conclusion: The findings highlight areas for improvement in healthy eating among children. The Healthy Eating Report Card could offer novel insights into intervention tools that promote healthy eating.

Sepsis is characterized as an uncontrolled inflammatory response. Spite et al. (Nature 461(7268):1287–1291, 2009 ) had demonstrated that resolvin D2, which is derived from docosahexaenoic acid (DHA), improves survival in cecal ligation and puncture (CLP)-initiated sepsis and enhances bacterial clearance without immune suppression. Resolvin D1, which is also derived from DHA and homologous with resolvin D2, is an endogenous anti-inflammatory and proresolving lipid molecule. We sought to investigate the effects of resolvin D1 on sepsis and to explore the mechanism of action. Six-to-eight-week-old male C57BL/6 mice were randomly divided into three groups: the sham group underwent the sham operation followed by tail vein injection of vehicle (0.1 % ethanol); the CLP group received vehicle (0.1 % ethanol) after CLP; the resolvin D1 group received resolvin D1 (100 ng) after CLP. Blood, peritoneal lavage fluid, and organs of mice were harvested 24 h after treatment for cytokine analysis, cell counts, bacterial cultures, histopathological studies, and apoptosis quantification. Compared with the vehicle control group, the survival rate and bacterial clearance of mice with sepsis induced by CLP were improved after resolvin D1 treatment, but the numbers of neutrophils in peritoneal lavage fluid, the inflammatory cytokines, the phosphorylation of the nuclear factor-κB (NF-κB) (P65) pathway, and the apoptosis rate of CD3 +  T lymphocytes of the thymus were suppressed. Resolvin D1 treatment improved survival in mice with sepsis induced by CLP, enhanced organism bacterial clearance, suppressed the increase of the numbers of neutrophils in peritoneal lavage fluid, reduced the release of inflammatory cytokines, and decreased the apoptosis rate of CD3 +  T lymphocytes of the thymus. These results suggest that resolvin D1 may attenuate the degree of inflammatory reaction in sepsis caused by CLP, without harming the host defense response.

A “rock bridge”, defined as the closest distance between two joints in a rock mass, is an important feature affecting the jointed rock mass strength. Artificial jointed rock specimens with two parallel joint fractures were tested under uniaxial compression and numerical simulations were carried out to study the effects of the inclination of the rock bridge, the dip angle of the joint, rock bridge length, and the length of joints on the strength of the jointed rock mass. Research results show: (1) When the length of the joint fracture, the length of the rock bridge, and the inclination of the rock bridge stay unchanged, the uniaxial compressive strength of the specimen gradually increases as the inclination of the joint fracture increases from 0°to 90°. (2) When the length of the joint fracture, the length of the rock bridge, and the inclination of the joint fracture stay unchanged, the uniaxial compressive strength of the specimen shows variations in trends with the inclination of the rock bridge increasing from 30° to 150° (3). In the case when the joint is angled from the vertical loading direction, when the dip angle of the joint fracture, the inclination of the rock bridge, and the length of the rock bridge stay unchanged, the uniaxial compressive strength of the specimen gradually decreases with an increasing length of joint fracture. When the dip angle of the joint fracture, the inclination of the rock bridge, and the length of the joint fracture stay unchanged, the uniaxial compressive strength of the specimen does not show a clear trend with an increase of the length of the rock bridge.