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Pathogenesis of pregnancy toxemia (PT) is believed to be associated with the disruption of lipid metabolism. The present study aimed to explore the underlying mechanisms of lipid metabolism disorder in the livers of ewes with PT. In total, 10 pregnant ewes were fed normally (control group) whereas another 10 were subjected to 70% level feed restriction for 15 days to establish a pathological model of PT. Results showed that, as compared with the controls, the levels of blood β-hydroxybutyrate (BHBA), non-esterified fatty acids (NEFAs) and cholesterol were greater (P<0.05) and blood glucose level was lower (P<0.05) in PT ewes. The contents of NEFAs, BHBA, cholesterol and triglyceride were higher (P<0.05) and glycerol content was lower (P<0.05) in hepatic tissues of PT ewes than those of the controls. For ewes with PT, excessive fat vacuoles were observed in liver sections stained with hematoxylin–eosin; furthermore, inner structures of hepatocytes including nuclei, mitochondria and endoplasmic reticulum were damaged seriously according to the results of transmission electron microscope. Real-time PCR data showed that compared with the controls, the expression of hepatic genes involved in fatty acid oxidation (FAO) and triglyceride synthesis (TGS) was enhanced (P<0.05) whereas that related to acetyl-CoA metabolism (ACM) was repressed (P<0.05) in PT ewes. Generally, our results showed that negative energy balance altered the expression of genes involved in FAO, ACM and TGS, further caused lipid metabolism disorder in livers, resulting in PT of ewes. Our findings may provide the molecular basis for novel therapeutic strategies against this systemic metabolic disease in sheep.
Diarrhea is a common cause of morbidity and mortality and the incidence of diarrhea in the world has changed little over the past four decades. To assess the prevalence of and healthcare practices for diarrhea, a cross-sectional study was conducted in Pudong, Shanghai, China. In October 2014, a total of 5324 community residents were interviewed. Respondents were asked if they had experienced diarrhea (defined as ⩾3 passages of watery, loose, bloody, or mucoid stools within a 24-h period) in the previous month prior to the interview. The monthly prevalence of diarrhea was 4·1% (95% CI: 3·3–4·8), corresponding to an incidence rate of 0·54 episodes per person-year. The proportion of individuals with diarrhea who sought healthcare was 21·2% (95% CI: 13·4–29·0). Diarrhea continues to impose a considerable burden on the community and healthcare system in Pudong. Young age and travel were identified as predictors of increased diarrhea occurrence.
The fruit of Ligustrum lucidum (FLL, Nuzhenzi in Chinese) is an important traditional medicine, and have attracted significant research attention because of their various biological activities. However, there are few research reports available on the use of FLL as a feed additive in livestock nutrition, particularly in layers. This study was conducted to determine the effects of supplementation of the diet of laying hens with FLL on laying performance, egg quality and blood metabolites. A total of 360 72-week-old hens were allocated to three dietary treatments (eight replications of 15 hens/treatment group) and were fed either a control diet or a diet supplemented with an inclusion level of 0.25% or 0.50% of FLL powder in the final feed, until 78 weeks of age. Hens were housed in a three-tier cage system. Feed and water were provided ad libitum. Blood samples and eggs were collected at the end of the experiment. The results showed that dietary supplementation with FLL did not affect egg weight, feed conversion ratio, eggshell thickness, albumen height, egg yolk color, eggshell breaking strength or egg shape index. However, FLL supplementation significantly decreased (P<0.001) mortality, cracked-egg rate and blood serum levels of cholesterol, low-density lipoprotein cholesterol, triglycerides and alanine aminotransferase, and increased (P<0.001) blood serum levels of high-density lipoprotein cholesterol. No differences in serum levels of total protein, albumin, glucose, calcium, aspartate aminotransferase or alkaline phosphatase were observed in hens fed FLL compared with the control group. It can be concluded that FLL, at a supplementation level of 0.25% final feed, can be used as an effective feed additive to improve the performance of laying hens during the late laying period.
Foxtail millet (Setaria italica (L.) P. Beauv.) is a naturally stress-tolerant plant, a major reserve crop and a model for panicoid grasses. The recent completion of the S. italica genome facilitates identification and characterization of WRKY transcription factor family proteins that are important regulators of major plant processes, including growth, development and stress response. The present study identified 103 WRKY transcription factor-encoding genes in the S. italica genome. The genes were named SiWRKY1–SiWRKY103 according to their order on the chromosomes. A comprehensive expression analysis of SiWRKY genes among four different tissues was performed using publicly available RNA sequencing data. Eighty-four SiWRKY genes were more highly expressed in root tissue than in other tissues and nine genes were only expressed in roots. Additionally, real-time quantitative polymerase chain reaction was performed to comprehensively analyse the expression of all SiWRKY genes in response to dehydration. Results indicated that most SiWRKY genes (over 0.8) were up-regulated by drought stress. In conclusion, genome-wide identification and expression profiling of SiWRKY genes provided a set of candidates for cloning and functional analyses in plants’ response to drought stress.
A new death line for radio pulsars is presented in this paper within the framework of vacuum gap and inverse Compton scattering (ICS) induced pair production process. The 8.5s period pulsar PSR J2144-3933 is located above the death line without any additional assumptions. An “appearance line” instead of the so-called “Hubble line”, is also presented in this paper. Both of those two lines fit observations well.
We report on the properties of the hot gaseous halos of 10 nearby ultraluminous IRAS galaxies from Chandra observations. There exists diffuse soft X-ray emission surrounding the central nucleus within 10 kpc of the nuclear region with a temperature of about 0.7 keV and metallicity about Z ~ 1.0Z⊙. Also, emission lines from α elements and ions for are seen in all nearby ULIRGs in our sample. Outside the central region, the Chandra observations reveal a more extended hot gaseous halo with a temperature of about 0.6 keV and low metallicity (Z ~ 0.1Z⊙) for some of the ULIRGs. We discuss the nature and the implications of our results for the origin of X-ray halos in elliptical galaxies and the constraints this places on the feedback process.
The unprecedented combination of spatial resolution and stability achieved by the Solar Oscillations Investigation/Michelson Doppler Imager on SOHO has opened up new opportunities for the analysis of solar surface oscillations of high spatial frequencies. In this regime the oscillations are essentially plane waves, amenable to the techniques of ring-diagram analysis of their three-dimensional power spectra. This approach holds the promise of measuring fluid motions and possibly magnetic fields in spatially-resolved structures within the uppermost levels of the convective envelope, a region unresolved by the global modes. Atmospheric g-modes trapped above the photosphere may also be detectable. We review the first results of plane-wave analysis of various types of SOI data and comparisons with the analyses of comparable ground-based datasets.
Both growth and immune capacity are important traits in animal breeding. The animal quantitative trait loci (QTL) database is a valuable resource and can be used for interpreting the genetic mechanisms that underlie growth and immune traits. However, QTL intervals often involve too many candidate genes to find the true causal genes. Therefore, the aim of this study was to provide an effective annotation pipeline that can make full use of the information of Gene Ontology terms annotation, linkage gene blocks and pathways to further identify pleiotropic genes and gene sets in the overlapping intervals of growth-related and immunity-related QTLs. In total, 55 non-redundant QTL overlapping intervals were identified, 1893 growth-related genes and 713 immunity-related genes were further classified into overlapping intervals and 405 pleiotropic genes shared by the two gene sets were determined. In addition, 19 pleiotropic gene linkage blocks and 67 pathways related to immunity and growth traits were discovered. A total of 343 growth-related genes and 144 immunity-related genes involved in pleiotropic pathways were also identified, respectively. We also sequenced and genotyped 284 individuals from Chinese Meishan pigs and European pigs and mapped the single nucleotide polymorphisms (SNPs) to the pleiotropic genes and gene sets that we identified. A total of 971 high-confidence SNPs were mapped to the pleiotropic genes and gene sets that we identified, and among them 743 SNPs were statistically significant in allele frequency between Meishan and European pigs. This study explores the relationship between growth and immunity traits from the view of QTL overlapping intervals and can be generalized to explore the relationships between other traits.
While oral antidepressants reach efficacy after weeks, single-dose intravenous (i.v.) ketamine has rapid, yet time-limited antidepressant effects. We aimed to determine the efficacy and safety of single-dose i.v. ketamine augmentation of escitalopram in major depressive disorder (MDD).
Thirty outpatients with severe MDD (17-item Hamilton Rating Scale for Depression total score ⩾24) were randomized to 4 weeks double-blind treatment with escitalopram 10 mg/day+single-dose i.v. ketamine (0.5 mg/kg over 40 min) or escitalopram 10 mg/day + placebo (0.9% i.v. saline). Depressive symptoms were measured using the Montgomery–Asberg Depression Rating Scale (MADRS) and the Quick Inventory of Depressive Symptomatology – Self-Report (QIDS-SR). Suicidal ideation was evaluated with the QIDS-SR item 12. Adverse psychopathological effects were measured with the Brief Psychiatric Rating Scale (BPRS)-positive symptoms, Young Mania Rating Scale (YMRS) and Clinician Administered Dissociative States Scale (CADSS). Patients were assessed at baseline, 1, 2, 4, 24 and 72 h and 7, 14, 21 and 28 days. Time to response (⩾50% MADRS score reduction) was the primary outcome.
By 4 weeks, more escitalopram + ketamine-treated than escitalopram + placebo-treated patients responded (92.3% v. 57.1%, p = 0.04) and remitted (76.9% v. 14.3%, p = 0.001), with significantly shorter time to response [hazard ratio (HR) 0.04, 95% confidence interval (CI) 0.01–0.22, p < 0.001] and remission (HR 0.11, 95% CI 0.02–0.63, p = 0.01). Compared to escitalopram + placebo, escitalopram + ketamine was associated with significantly lower MADRS scores from 2 h to 2 weeks [(peak = 3 days–2 weeks; effect size (ES) = 1.08–1.18)], QIDS-SR scores from 2 h to 2 weeks (maximum ES = 1.27), and QIDS-SR suicidality from 2 to 72 h (maximum ES = 2.24). Only YMRS scores increased significantly with ketamine augmentation (1 and 2 h), without significant BPRS or CADSS elevation.
Single-dose i.v. ketamine augmentation of escitalopram was safe and effective in severe MDD, holding promise for speeding up early oral antidepressant efficacy.
We derive zphot for sources in the entire (~0.4 deg2) H-HDF-N field with the EAzY code, based on PSF-matched broad-band (U band to IRAC 4.5 μm) photometry. Our catalog consists of a total of 131,678 sources. We find σNMAD = 0.029 for non-X-ray sources. We also classify each object as a star or galaxy through SED fitting. Furthermore, we match our catalog with the 2 Ms CDF-N main X-ray catalog. For the 462 matched non-stellar X-ray sources, we improve their zphot quality (σNMAD = 0.035) by adding three additional AGN templates. We make our photometry and zphot catalog publicly available.
We numerically investigate the thermally unstable accretion discs around spinning black holes with different spins. We adopted an additional evolutionary viscosity equation to replace the standard alpha-prescription based on the results of two MHD simulations. We find an interesting oscillation when accretion switches to slim disc mode. The oscillation arises from the sonic point of accretion flow and propagates outwards. We mimic the bolometric light-curve and find a series of harmonics on its power spectrum. The frequency ratio of those harmonics is a regular integer series. The lowest frequency of the harmonics is identical to the prediction of trapped p-mode in QPO theory.
Low-cost La(FexSi1-x)13 alloys exhibiting the large magnetocaloric effect (MCE) are one of the most promising magnetic refrigerant candidates for room temperature magnetic refrigeration. The NaZn13-type phase (hereinafter 1:13 phase) is believed to play a key role in the MCE of these alloys. While the formation of the 1:13 phase directly from the melt upon cooling was challenging, in this paper we demonstrate that the 1:13 phase can be formed directly during solidification. We found that three kinds of solidification microstructure were formed because a competitive nucleation occurred between the 1:13 and α-(Fe,Si) phase during the solidification of LaFe11.5Si1.5 alloy. In case of a high cooling speed, a large amount of NaZn13–type phase with equiaxed grains and a small amount of α-(Fe,Si) phase were formed because of a dominant nucleation rate of 1:13 phase. When the cooling rate was small, a large number of α-(Fe,Si) phase with dendrites were formed because the nucleation rate of α-(Fe,Si) phase is larger than that of the 1:13 phase. These results revealed that nucleation rates of phases is very important to the composition formation and microstructure of LaFe11.5Si1.5 alloys.
This paper presents a novel analysis approach by considering multiple crack interaction in achieving FAA certification for durability and damage tolerance of exterior attachment installations on an aircraft fuselage according to FAA policy on Certification by Analysis-Supported-by-Test (CAST). Durability and damage tolerance evaluation of an aircraft component requires assessment of damage initiation and fatigue crack propagations under service loading, which consists of complex loading types, paths and variable amplitudes. Both simulation and service experience showed that multiple cracks developed in the fuselage skin and doublers that are made of wrought aluminum alloys. Progressive failure analysis (PFA) tool was used to simulate the fatigue damage initiation life using a scale-down stress-life property. A virtual crack closure technique (VCCT) was implemented to evaluate fatigue crack growth with interactions between cracks from different parts in a component, which preserves conservativeness. The fatigue crack growth data is obtained uniquely from an analytical extension of fatigue crack growth data of thin aluminum sheet. Fatigue crack growth analysis showed that only a few initiated cracks propagated steadily before a crack became visible under inspection, which was validated by comparison to service history. Eventually one crack became dominate in the fracturing process thereby setting an inspection time. Analysis also showed that fatigue damage state in the components at the designed operational life will not exceed the static safety requirements. Therefore, FAA accepted the damage tolerance analysis and the aircraft retained certification with no need for repair.
Haemorrhagic fever with renal syndrome (HFRS) is a type of vector-borne zoonosis sensitive to climate change. To explore the short-term effect of air temperature and amount of precipitation on HFRS incidence, a total of 13 722 clinically confirmed HFRS cases from January 1977 to December 2001 in Junan County, China were included in this study. According to symmetric bidirectional case-crossover design, the hazard period (the three calendar months preceding the month when the case was diagnosed) and the control period (the same calendar month of the year before and the year after the hazard period) matched and conditional logistic regression was used to examine the effect of monthly mean temperature and precipitation on the risk of HFRS. The results showed the facilitating climatic conditions for HFRS included: condition with moderate mean air temperature (10–25 °C) and abundant precipitation (>120 mm) 3 months before [odds ratio (OR) 1·346, 95% confidence interval (CI) 1·191–1·522] and 2 months before (OR 1·193, 95% CI 1·063–1·339); and condition with temperature >25 °C and abundant precipitation (>120 mm) 3 months before (OR 1·17, 95% CI 1·004–1·363). Temperature of 10–25 °C and moderate precipitation (10–120 mm) in the current month was the most favourable condition for HFRS incidence.
Pulsatile tinnitus usually originates from vascular structures, causing an arterial or venous bruit. We report a new cause of pulsatile tinnitus: a focal defect of the mastoid bone shell in the region of the transverse-sigmoid junction, with a normal transverse-sigmoid sinus.
Participants and intervention:
Three patients complained of unilateral, pulsatile tinnitus present for many years. They were identified as having a focal defect of the mastoid bone shell in the region of the transverse-sigmoid junction. The patients underwent transmastoid reconstruction of the mastoid bone shell overlying the transverse-sigmoid sinus.
All three patients reported immediate resolution of their symptoms, and were asymptomatic at final follow up.
A focal defect of the mastoid bone shell overlying the transverse-sigmoid sinus, with no abnormality of the sinus itself, may be a new cause of pulsatile tinnitus. Surgical reconstruction of the mastoid bone shell overlying the transverse-sigmoid sinus can provide lasting symptom relief for patients with pulsatile tinnitus and computed tomographic evidence of the defect.
We have studied the kinetics of the chemical reaction between Mg and B by differential thermal analysis. There are two exothermal peaks observed at 500 and 650 °C. We speculate that the first exothermal peak is mainly related to the chemical reaction between Mg and oxygen, forming MgO. The second exothermal peak, which coincides with the melting point of Mg, clearly indicates the chemical reaction between Mg and B. The effect of synthesis conditions and defects on the transport property of MgB2 has been investigated. A correlation between the microstrain, the lattice parameters, and the Mg concentration were observed and are discussed.
In this work, the surface properties of a DNA microarray formed on silicon based solid support are studied at different stages during the hybridization process. A modified immobilization process using the covalent immobilization of thiol-terminated DNA oligonucleotides on self-assembled layers of (3-mercaptopropyl) trimethoxysilane (MPTS) by disulfide bond formation is used to selectively attach DNA probes onto the surface of silicon dioxide. Contact angle measurement is used to monitor the bonding of MPTS on the surface. Atomic force microscopy (AFM) shows an increase in particle size before and after the growth of the MPTS layer. Fluorescence microscopy reveals the success of hybridization of complementary oligonucleotides labeled by FAM to the probe. The effects of modified immobilization process on other common material in silicon processing are also studied. As a result of the corrosive chemical used in the process, common metals used in micro-fabrication processes like aluminum are etched away. Silicon nitride is not affected by the immobilization and hybridization process, and thus can be used as a passivation and isolation material to conform the DNA to a specific area for DNA microarray to reduce cross-talk. The fluorescence image from the scanner indicates silicon nitride can effectively be used as an isolation material with linewidth down to 1 μm.
On the basis of Raman, photoluminescence, and absorption studies of porous and nanoparticle silicon we propose that the strong luminescence in porous silicon results from strained silicon quantum dots. A silicon nanoparticle is a special Jahn-Teller system induced by extended electron states rather than localized state. Thus Raman scattering and photoluminescence in porous silicon are multi-phonon assisted free electronic transition processes, all observed anomalous properties of porous silicon can be clearly explained by using this strained quantum dot model.
High-energy heavy-ion irradiation has been shown to be effective in introducing flux-pinning defects in Y123 single crystals. Contrary to electron, low energy proton, and fast neutron irradiation, high-energy heavy-ion irradiation produces defects beneficial to flux pinning through the electronic (rather than nuclear) stopping mechanism. This type of stopping results in tubular defects many microns long that can increase the range of irreversible magnetic behavior to higher fields. In contrast, dense arrays of small defects (size < 100 Ang.) produce enhanced critical currents at low fields but do not extend the range of irreversible behavior significantly. We have used two ion-energy combinations in which the electronic stopping powers vary by nearly two orders of magnitude. The difference in stopping powers results in very different defect types, ranging from well oriented and dense (Xe) to much less well oriented and shorter (O) tubular defects. A novel analysis of the ac μ data indicates that the strong pinning introduced by the Xe irradiation breaks the vortex glass picture in favor of an individual pinning model, while O irradiation does not.
Transition metal impurities such as Fe, Ni, and Co can be intercalated into the van der Waals gap of layer structure dichalcogenides and these modify the charge-density wave (CDW) structure and CDW energy gaps. Ordered superlattices associated with antiferromagnetic phases can be detected by both scanning tunneling microscopy (STM) and atomic force microscopy (AFM). STM spectroscopy indicates the formation of a mixed spin-density-wave (SDW) and CDW (SDWCDW) in the doped materials. The quasi-one dimensional trichalcogenide NbSe3 exhibits two CDW transitions and the presence of dilute transition metal impurities produces ordered superlattices due to long range screening of the impurities.