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White beam synchrotron X-ray topography has been applied both to the characterization of two semiconductor heterostructures, GaAs/Si and InxGa1-xAs/GaAs strained layers, and a substrate to be used for growing semiconductor epilayers, Cd1-xZnxTe. In the case of the heterostructures, misfit dislocations were observed using depth sensitive X-ray topographic imaging in grazing incidence Bragg-Laue geometries. The X-ray penetration depth, which can be varied from several hundreds of angstroms to hundreds of micrometers by rotating about the main reflection vector, which in this specific case was (355), is governed by kinernatical theory. This is justified by comparing dislocation contrast and visibility with the extent of the calculated effective misorientalion field in comparison to the effective X-ray penetration depth. For the case of Cd1-xZnxTe, twin configurations are observed, and their analysis is presented.
The triplite LiFeSO4F displays both the highest potential ever reported for an Fe-based compound, as well as a comparable specific energy with that of popular LiFePO4. The synthesis is still a challenge because the present approaches are connected with long time, special equipments or organic reagents, etc. In this work, the triplite LiFeSO4F powder was synthesized through an ambient two-step solid-state route. The reaction process and phase purity were analyzed, coupled with structure refinement and electrochemical test.
The study investigated whether different dietary energy and protein sources affect laying performance, antioxidant status, fresh yolk fatty acid profile and quality of salted yolks in laying ducks. In all, 360 19-week-old Longyan ducks were randomly assigned to four diets in a factorial arrangement (2×2). The four diets consisted of two energy sources, corn (CO) or sorghum (SO) and two protein sources, soybean meal (SM) and rapeseed meal with corn distillers dried grains with solubles (RMD), and each treatment contained six replicates of 15 birds each. The experimental diets were isocaloric (metabolizable energy, 10.84 MJ/kg) and isonitrogenous (CP, 17%). The results showed that egg production, average egg weight, egg mass and feed conversion ratio were not affected by diets (P>0.05). Plasma contents of reduced glutathione (GSH), GSH/oxidized glutathione and total antioxidant capacity were lower (P<0.05) in ducks fed the RMD diets compared with those fed SM diets with a substantial increase (P=0.006) in plasma content of malondialdehyde (MDA). Egg yolks from ducks fed SO diets had higher proportions of polyunsaturated fatty acids (PUFA) and lower saturated and monounsaturated fatty acids compared with CO diets (P<0.001). Similarly, ducks fed RMD diets had a higher content of PUFA and n-6/n-3 ratio in fresh yolks (P<0.001), and increased salted yolk MDA, carbonylated proteins content and incidence of hard salted yolks (P<0.05) compared with SM diets. Scanning electron microscopy showed that salted yolks contained rougher polyhedral granules and fewer fat droplets, and were surrounded with a layer of bunchy fibers in ducks fed SO+RMD than those fed CO+SM diet. In conclusion, the current study showed that feeding laying ducks with diets containing SO or RMD reduced antioxidant capacity and increased egg yolk concentrations of PUFA. It appeared that egg yolks from ducks fed these diets were more sensitive to lipid peroxidation and protein oxidation during salting, and reduced the quality of salted yolks.
The mammalian target of rapamycin (mTOR) has been shown to be involved in lipopolysaccharide (LPS)-induced immune responses in many mammal cells. Here, we suggest that the mTOR pathway is involved in the intestinal inflammatory responses evoked by LPS treatment in chicken embryos. The intestinal tissue from Specific pathogen free chick embryos was cultured in the presence of LPS for 2 h. Secretory immunoglobulin A (sIgA) concentrations, messenger RNA (mRNA) expression of cytokines, and protein levels of nuclear factor-κB (NF-κB), mitogen-activated protein kinase (MAPK), mTOR and p70 ribosomal S6 kinase (p70S6K) were determined. The results showed that LPS treatment increased sIgA concentrations in a dose-dependent manner. The mRNA levels of interleukine (IL)-6, IL-8, IL-10, tumor necrosis factor-α and Toll-like receptor (TLR) 4 were upregulated by LPS treatment (P<0.05). Lipopolysaccharide increased the phosphorylation of Jun N-terminal kinase (JNK), p38 MAPK and NF-κB (P<0.05) while decreasing the phosphorylation level of mTOR (P<0.05). Supplementation of leucine at doses of 10, 20 and 40 mM dose-dependently decreased sIgA production. Leucine supplementation at 40 mM restored the phosphorylation level of mTOR and p70S6K while suppressing the phosphorylation levels of NF-κB (P<0.05) and partially down-regulating the phosphorylation of p38 MAPK and JNK. The transcription of IL-6 was significantly decreased by leucine supplementation. These results suggested that leucine could alleviate LPS-induced inflammatory responses by down-regulating NF-κB signaling pathway and evoking mTOR/p70S6K signaling pathway, which may involve in the regulation of the intestinal immune system in chicken embryos.
Little is known about the joint mental health effects of air pollution and tobacco smoking in low- and middle-income countries.
To investigate the effects of exposure to ambient fine particulate matter pollution (PM2.5) and smoking and their combined (interactive) effects on depression.
Multilevel logistic regression analysis of baseline data of a prospective cohort study (n=41785). The 3-year average concentrations of PM2.5 were estimated using US National Aeronautics and Space Administration satellite data, and depression was diagnosed using a standardised questionnaire. Three-level logistic regression models were applied to examine the associations with depression.
The odds ratio (OR) for depression was 1.09 (95% CI 1.01–1.17) per 10 μg/m3 increase in ambient PM2.5, and the association remained after adjusting for potential confounding factors (adjusted OR = 1.10, 95% CI 1.02–1.19). Tobacco smoking (smoking status, frequency, duration and amount) was also significantly associated with depression. There appeared to be a synergistic interaction between ambient PM2.5 and smoking on depression in the additive model, but the interaction was not statistically significant in the multiplicative model.
Our study suggests that exposure to ambient PM2.5 may increase the risk of depression, and smoking may enhance this effect.
Astronomy cloud computing environment is a cyber-Infrastructure for Astronomy Research initiated by Chinese Virtual Observatory (China-VO) under funding support from NDRC (National Development and Reform commission) and CAS (Chinese Academy of Sciences). Based on virtualization technology, astronomy cloud computing environment was designed and implemented by China-VO team. It consists of five distributed nodes across the mainland of China. Astronomer can get compuitng and storage resource in this cloud computing environment. Through this environments, astronomer can easily search and analyze astronomical data collected by different telescopes and data centers , and avoid the large scale dataset transportation.
In tritrophic ‘plants–herbivores–natural enemies’ systems, there are relatively few reports concerning the role(s) of kairomones in pupal parasitism. Chouioia cunea Yang (Hymenoptera: Eulophidae), an endoparasitic chalcid wasp, parasitizes pupae of the fall webworm (Hyphantria cunea Drury). The role of host-related kairomones was investigated using electroantennogram (EAG) and behavioral techniques. Chemicals from some host stages (pupae) and host by-products (frass), induced arrestment behavior of female parasitoids, while chemicals from prepupae, were inactive. Gas chromatography–mass spectrometry analysis of volatiles collected from pupae, frass and prepupae using solid-phase microextration revealed seven compounds with carbon chain lengths ranging from C4 to C20. All of the chemicals elicited significant EAG responses in C. cunea. Y-tube olfactometer bioassays demonstrated a significant positive response of mated female C. cunea to 1-dodecene. These data provide a better understanding of the host location mechanisms of pupal parasitoid.
Radiocarbon dating by accelerator mass spectrometry (AMS) of the shell bar section of Qaidam Basin, NE Tibetan Plateau, shows that this section was formed between ~39.7 and ~17.5 14C kyr BP and represented the highest paleolake development period since the Late Pleistocene. It was difficult to obtain reliable dates due to the low organic carbon content, which was formed mainly by authochtonous algae-bacteria (Zhang et al. 2007a). In order to improve the dating, 14C ages of both the alkali residual and acid-soluble components of the organic carbon were measured to check the consistency of the dating results. Total organic carbon (TOC) content and stable carbon isotopes (δ13Corg) might also be used as critical references for checking the reliability of dates. For example, in our study of the shell bar section from Qaidam Basin, we found that when the TOC content was higher than 0.15% and/or δ13Corg was lower than −23, the AMS dates were reliable. AMS dating of fossil shells demonstrated that they could provide valuable age information. The ages given by fossil shells are comparable to those of bulk carbonate from a similar sampling site, and are about 15~18 kyr older than the ages given by organic matter. Due to the U/Th dating requirements and open nature of the system, we concluded that U/Th dating results are unreliable and that this technique is unsuitable for dating halite deposits from Qaidam Basin.
Accurate and reliable dating of paleosols, animal remains, and artifacts is of crucial importance in reconstructing environmental change and understanding the interrelationship between human activities and natural environments. Dating different materials in the same sample can help resolve problems such as soil carbon sources and carbon storage state. Conventional radiocarbon dating of soil (inorganic and organic matter) and accelerator mass spectrometry (AMS) dating of animal remains (fossil bones and teeth) result in different ages for materials from the same sample position in a typical loess section at Xinglong Mountain, Yuzhong County, Gansu Province in NW China. Inorganic matter is ∼3400 yr older than organic matter, 4175 ± 175 cal BP to 3808 ± 90 cal BP. A 1610-yr difference between the 14C ages of fossils (animal bones and teeth) and soil organic matter suggests that a depositional hiatus exists in the studied profile. The varying 14C ages of fossils and soil organic and inorganic matter have important implications for paleoclimate reconstructions from loess sections. It is critical to consider the meaning of the variable 14C ages from different material components from the same sample position in terms of soil organic and inorganic carbon storage, vegetation history reconstruction, archaeology, and the study of ancient civilizations.
Conventional and accelerator mass spectrometry (AMS) radiocarbon, TL, OSL, and IRSL dating results on samples from the cores D100 and I70 from Ejina Basin, one of the most important inland basins in arid-hyperarid NW China, show that it is difficult to determine the ages of sediments at different depths. AMS ages of core D100 samples demonstrate that the sediments at depths from 10 to 90 m were formed between 14 to 30 kyr BP. The inverted ages from both the D100 and I70 cores imply that there was a strong reworking of the sediments during and after deposition processes. The inverted ages also indicate drastic fluctuations of groundwater bearing soluble organic matters, which might be related to neotectonic activities and climate changes during the period. Consequently, it is impossible to establish an accurate and reliable chronology for the cores based only on these dates. All AMS ages, if they are reliable and acceptable, indicate a high deposition rate (5∼8 mm/yr), and since all TL, OSL, and IRSL ages are much older than those given by AMS, it makes these methods questionable for determining the ages of lacustrine-fluvial-alluvial deposits.
This paper presents an analytical study on the buckling of cylindrical shells with arbitrary circumferential thickness variations under external pressure. Firstly, based on the thin shell theory and separation of variables, corresponding ordinary differential equations of laterally pressured cylinders are obtained. Secondly, the general asymptotic formula of buckling load, which is in terms of thickness variation parameter up to arbitrary order, is derived by combining the perturbation method and Fourier series expansion. Thirdly, the effects of uniform and circumferential modal thickness variations on the buckling of cylindrical shells under external pressure are investigated, respectively, and the results agree well with those available in literature. Particularly, the buckling load reduction of cylinders with circumferential modal thickness variation obtained by the proposed method coincides with the numerical results presented by Gusic et al. This analytical method is applicable for evaluating the stability of laterally pressured cylindrical shells with arbitrary circumferential thickness variations, once the thickness variation is known.
Soluble starch synthase II (SSII) plays an important role in the biosynthesis of starch and in rice it consists of three isoforms encoded by SSII-1, SSII-2 and SSII-3. However, the genetic effects of various SSII alleles on grain quality have not been systematically characterized. In the present study, the japonica alleles on SSII-1, SSII-2 and SSII-3 (SSIIa) loci from a japonica cultivar, Suyunuo, were respectively introgressed by molecular marker-assisted selection into a typical indica cultivar, Guichao2, through successive backcrossing, generating three sets of near-isogenic lines (NILs). Grain quality and starch property analysis showed that NIL-SSII-3j exhibited significant decreases in the following parameters: amylose content, average granule size, and setback viscosity and consistency; but increases in peak viscosity, hot paste viscosity, gelatinization temperature and relative crystallinity. Moreover, the proportion of short amylopectin chains and branching degree also increased when compared with those of NIL-SSII-3i (Guochao2). Similar effects were observed in NIL-SSII-1j, and certain alterations in the fine structure of starch (granule size) were revealed. However, NIL-SSII-2j did not exert significant effect on grain quality and starch properties. In brief, among the SSII gene family, the functional diversity occurred on SSII-1 and SSII-3, and not on SSII-2. Therefore, it appears that more attention should be directed to SSII-1 and SSII-3 loci for improving the eating and cooking quality of rice.
The growing numbers of brown dwarfs have largely been divided into two new spectral classes, L and T. Subclassification systems for L, based on optical (0.6–1.0 μm) spectra, have existed since 1999, but there is a need for infrared systems for both spectral classes. The differences in the infrared (1.0–2.5 μm) characteristics of L spectra and T spectra observed prior to 2000 are huge, all then-known T dwarfs showing strong methane absorption bands, and all L dwarfs devoid of these bands. However, in the last 2–3 years a significant number of brown dwarfs with infrared spectra in transition between the L and first observed T types have been discovered. The spectra of late L dwarfs and these “transition objects” can be put into a well ordered sequence of increasing H2O and CH4 band strengths and decreasing CO band strengths. Specific infrared spectral indicators have been found that allow the L and T sequences to be linked and the boundary between L and T to be precisely defined. In current T classification schemes the transition objects are defined as early T dwarfs. We recommend that the boundary between the L and T classes be defined as the first appearance of methane absorption just longward of 1.60 μm, in the H band.
The photospheric spectra of all L and T dwarfs contain strong molecular bands and alkali absorption features, and those of L and early T dwarfs are also affected by dust. Although work on atmospheric models is addressing the treatment of dust, and is increasing the completeness of molecular opacity linelists, the effective temperatures of L and T dwarfs cannot be derived confidently from the modelled spectral energy distributions. However, because the radii of brown dwarfs older than 0.1 Gyr vary little with mass, measurements of intrinsic luminosity (i.e. total integrated flux and parallax) accurately determine effective temperature. Using this method we find a well constrained relationship between the effective temperatures of L and T dwarfs and spectral type, but with temperature nearly constant from L7 to T4. More work is required to determine the uniqueness of this relationship and to constrain the masses and ages of brown dwarfs.
Over the past decade, “thin flux tube” models have proven successful in explaining many properties of active regions in terms of magnetic flux tube dynamics in the solar interior. On the other hand, recent 2-D MHD simulations of the emergence of magnetic flux have shown that many of the assumptions adopted in the thin flux tube approximation are invalid. For example, unless the flux tubes exhibit a large degree of initial field line twist — and observations of emerging active regions suggest they do not — they will fragment (break apart) before they are able to emerge through the surface. We attempt to resolve this paradox using a number of 3-D MHD simulations (in the anelastic approximation) that describe the rise and fragmentation of twisted magnetic flux tubes. We find that the degree of fragmentation of an evolving Ω-loop depends strongly on the 3-D geometry of the loop, and that the Coriolis force plays a dynamically important role in the evolution and emergence of magnetic flux.
Post-irradiation rhinosinusitis is one of the most common untoward side effects in patients with nasopharyngeal carcinoma. This study aimed to evaluate the effect of fluticasone propionate aqueous nasal spray on post-irradiation rhinosinusitis.
Nasopharyngeal carcinoma patients who had undergone radiotherapy and subsequently developed chronic rhinosinusitis were randomised to receive either fluticasone propionate aqueous nasal spray 200 µg plus nasal irrigation or a single nasal irrigation, for six months. A questionnaire, nasal endoscopy and computed tomography were used to evaluate rhinosinusitis severity, at the beginning of treatment, and at three and six months after treatment.
The group who received fluticasone propionate aqueous nasal spray combined with irrigation had fewer nasal complaints (overall symptoms, blocked nose and headache were reduced), a better quality of life and less severe endoscopic findings than those who only received nasal irrigation at three and six months after treatment.
Nasal steroids are a safe and effective therapy for patients with post-irradiation rhinosinusitis.
The Oriental fruit moth, Grapholita molesta (Lepidoptera: Tortricidae), is a major pest of tree fruits worldwide, and the diapausing larvae overwinter in cryptic habitats. Investigations of overwintering G. molesta were conducted in adjacent peach, pear and apple orchards in Northern China over three consecutive winters to determine the overwintering site and habitat preferences of the moth. Counts of overwintering larvae in the different orchards demonstrated that the late-maturing peach orchard (‘Shenzhou honey peach’) was the most preferred overwintering habitat with more than 90% of the collected larvae. Larvae were more abundant in host trees, and they very rarely overwintered in the soil. The overwintering site preferences on the host trees were significantly different; over 50% larvae were located in the tree trunks, and followed by main branches. Most of the G. molesta overwintered on the sunny side of the host trees at or below 60 cm from the ground; a few were cocooned on the shaded sides of the trees or greater than 60 cm from the ground. G. molesta began overwintering between August and October, mid- to late September was the peak period for entering winter diapause during 2011–2013 (77.78, 67.59 and 71.15%, respectively). Our findings improve understanding of the orchard habitat and overwintering site preferences of G. molesta and would be useful in the development of efficient forecasting and pest-management strategies for orchards during the winter and early spring.
Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease that was caused by a novel bunyavirus, SFTSV. The study aimed to disclose the epidemiological and clinical characteristics of SFTSV infection in China so far. An integrated clinical database comprising 1920 SFTS patients was constructed by combining first-hand clinical information collected from SFTS sentinel hospitals (n = 1159) and extracted data (n = 761) from published literature. The considered variables comprised clinical manifestations, routine laboratory tests of acute infection, hospitalization duration and disease outcome. SFTSV-IgG data from 19 119 healthy subjects were extracted from the published papers. The key clinical variables, case-fatality rate (CFR) and seroprevalence were estimated by meta-analysis. The most commonly seen clinical manifestations of SFTSV infection were fever, anorexia, myalgia, chill and lymphadenopathy. The major laboratory findings were elevated lactate dehydrogenase, aminotransferase, followed by thrombocytopenia, lymphocytopenia, elevated alanine transaminase and creatine kinase. A CFR of 12·2% was estimated, significantly higher than that obtained from national reporting data, but showing no geographical difference. In our paper, the mortality rate was about 1·9 parts per million. Older age and longer delay to hospitalization were significantly associated with fatal outcome. A pooled seroprevalence of 3·0% was obtained, which increased with age, while comparable for gender. This study represents a clinical characterization on the largest group of SFTS patients up to now. A higher than expected CFR was obtained. A wider spectrum of clinical index was suggested to be used to identify SFTSV infection, while the useful predictor for fatal outcome was found to be restricted.
Precise control of structural parameters through nanoscale engineering to continuously tailor optical and electronic properties of functional nanomaterials remains an outstanding challenge. Previous work focused largely on chemical or physical interactions that occur under ambient pressures. In this article, we introduce a new pressure-directed assembly and fabrication method that uses a mechanical compressive force applied to nanoparticles (NPs) to induce structural phase transitions and consolidate new nanomaterials with precisely controlled structures and tunable properties. By manipulating NP coupling through external pressure instead of through chemistry, a reversible change in assembly structure and properties can be demonstrated. In addition, over a certain threshold, the external pressure forces these NPs into contact, allowing the formation and consolidation of one- to three-dimensional nanostructures. Through stress-induced NP assembly, unusual materials engineering and synthesis, in which morphology and architecture can be readily tuned to produce desired optical and electrical properties, appear feasible.