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Evidence from our research on young children's temporal understanding supports Hoerl & McCormack's view that young children rely on a temporal updating system to change representations over time. We propose that the shift from temporal updating to temporal reasoning is enabled by children's expanding representations of event sequences, along with developments in language, memory, and other cognitive competencies.
The effect of hot streaks from a gas turbine combustor on the thermodynamic load of internally air-cooled nozzle guide vanes (NGVs) and shrouds has been numerically investigated under flight conditions. The study follows two steps: one for the high-fidelity 60° combustor sector with simplified ten NGVs and three thermocouples attached; and the other for the NGV sectors where each sector consists of one high-fidelity NGV (probe NGV) and nine dummy NGVs. The first step identifies which NGV has the highest thermal load and provides the inlet flow boundary conditions for the second step. In the second step, the flow fields and thermal loads of the probe NGVs are resolved in detail.
With the systematically validated physical models, the two-phase flowfield of the combustor-NGVs sector has been successfully simulated. The predicted mean and maximum temperature at the combustor sector exit are in excellent agreement with the experimental data, which provides a solid basis for the hot-streak effect investigation. The results indicate that the second NGV, looking upstream from left, has the highest thermal load. Its maximum surface temperature is 8.4% higher than that for the same NGV but with the mean inlet boundary conditions, and 14.1% higher than the ninth NGV. The finding is consistent with the field-observed NGV damage pattern. To extend the service life of these vulnerable NGVs, some protection methods should be considered.
Enhancing the supply of arginine (Arg), a semi-essential amino acid, has positive effects on immune function in dairy cattle experiencing metabolic stress during early lactation. Our objective was to determine the effects of Arg supplementation on biomarkers of liver damage and inflammation in cows during early lactation. Six Chinese Holstein lactating cows with similar BW (508 ± 14 kg), body condition score (3.0), parity (4.0 ± 0), milk yield (30.6 ± 1.8 kg) and days in milk (20 ± days) were randomly assigned to three treatments in a replicated 3 × 3 Latin square design balanced for carryover effects. Each period was 21 days with 7 days for infusion and 14 days for washout. Treatments were (1) Control: saline; (2) Arg group: saline + 0.216 mol/day l-Arg; and (3) Alanine (Ala) group: saline + 0.868 mol/day l-Ala (iso-nitrogenous to the Arg group). Blood and milk samples from the experimental cows were collected on the last day of each infusion period and analyzed for indices of liver damage and inflammation, and the count and composition of somatic cells in milk. Compared with the Control, the infusion of Arg led to greater concentrations of total protein, immunoglobulin M and high density lipoprotein cholesterol coupled with lower concentrations of haptoglobin and tumor necrosis factor-α, and activity of aspartate aminotransferase in serum. Infusion of Ala had no effect on those biomarkers compared with the Control. Although milk somatic cell count was not affected, the concentration of granulocytes was lower in response to Arg infusion compared with the Control or Ala group. Overall, the biomarker analyses indicated that the supplementation of Arg via the jugular vein during early lactation alleviated inflammation and metabolic stress.
The co-occurrence of hepatic cystic echinococcosis (CE) and alveolar echinococcosis (AE) is extremely rare. Here, we present the clinical manifestations and treatment outcomes of three cases with co-occurring CE and AE in the liver. Computed tomography (CT), magnetic resonance imaging and 18FFluorodeoxyglucose Positron Emission Tomography-CT were used for preoperative diagnosis. Specimens were taken intraoperatively and sent for pathological studies to confirm the coexistence of CE and AE by laminated membrane, daughter cysts or germinal layer and infiltration structure. Albendazole was prescribed after operation for 12 months. All patients were completely recovered and showed no recurrence at last follow-up. Therefore, surgical intervention and postoperative application of albendazole are recommended for patients with concurrence of hepatic AE and CE.
Crystal structure and electronic structure of YMnO3 were investigated by X-ray diffraction and transmission electron microscopy related techniques. According to the density of states (DOS), the individual interband transitions to energy loss peaks in the low energy loss spectrum were assigned. The hybridization of O 2p with Mn 3d and Y 4d analyzed by the partial DOS was critical to the ferroelectric nature of YMnO3. From the simulation of the energy loss near-edge structure, the fine structure of O K-edge was in good agreement with the experimental spectrum. The valence state of Mn (+3) in YMnO3 was determined by a comparison between experiment and calculations.
Space Infrared Telescope for Cosmology and Astrophysics (SPICA), the cryogenic infrared space telescope recently pre-selected for a ‘Phase A’ concept study as one of the three remaining candidates for European Space Agency (ESA's) fifth medium class (M5) mission, is foreseen to include a far-infrared polarimetric imager [SPICA-POL, now called B-fields with BOlometers and Polarizers (B-BOP)], which would offer a unique opportunity to resolve major issues in our understanding of the nearby, cold magnetised Universe. This paper presents an overview of the main science drivers for B-BOP, including high dynamic range polarimetric imaging of the cold interstellar medium (ISM) in both our Milky Way and nearby galaxies. Thanks to a cooled telescope, B-BOP will deliver wide-field 100–350
m images of linearly polarised dust emission in Stokes Q and U with a resolution, signal-to-noise ratio, and both intensity and spatial dynamic ranges comparable to those achieved by Herschel images of the cold ISM in total intensity (Stokes I). The B-BOP 200
m images will also have a factor
30 higher resolution than Planck polarisation data. This will make B-BOP a unique tool for characterising the statistical properties of the magnetised ISM and probing the role of magnetic fields in the formation and evolution of the interstellar web of dusty molecular filaments giving birth to most stars in our Galaxy. B-BOP will also be a powerful instrument for studying the magnetism of nearby galaxies and testing Galactic dynamo models, constraining the physics of dust grain alignment, informing the problem of the interaction of cosmic rays with molecular clouds, tracing magnetic fields in the inner layers of protoplanetary disks, and monitoring accretion bursts in embedded protostars.
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
To compare the epidemiologic features (e.g. settings and transmission mode) and patient clinical characteristics associated with outbreaks of different norovirus (Nov) strains, we retrospectively analysed data of Nov outbreaks occurring in Guangzhou, China from 2012 to 2018. The results suggested that outbreaks of Nov GII.2, GII.17 and GII.4 Sydney exhibited different outbreak settings, transmission modes and symptoms. GII.2 outbreaks mainly occurred in kindergartens, elementary and high schools and were transmitted mainly through person-to-person contact. By contrast, GII.4 Sydney outbreaks frequently occurred in colleges and were primarily associated with foodborne transmission. Cases from GII.2 and GII.17 outbreaks reported vomiting more frequently than those from outbreaks associated with GII.4 Sydney.
Nucleos(t)ide analogues (NAs) are widely used for antiviral therapy in patients with chronic hepatitis B (CHB), but real-world data on treatment patterns and long-term clinical outcomes are not always available. Using data from electronic medical records between January 2011 and December 2016 in Shanghai, China, we evaluated patient characteristics, treatment patterns and clinical outcomes in patients with CHB. There were 6688 patients in the study cohort. The incidences of cirrhosis and hepatocellular carcinoma (HCC) were 41.0‰ and 6.8‰ person-years, respectively. There were more cirrhosis and HCC cases among patients who had shorter NA treatment duration (<365 days), or who were less compliant (<80%). In addition, increased risk of cirrhosis and HCC was observed in patients who did not achieve hepatitis B surface antigen (HBsAg) loss/seroconversion. Moreover, patients with cirrhosis developed after antiviral treatments had a higher incidence of HCC (adjusted hazard ratio 15.86, 95% confidence interval 7.35–34.24). Good compliance with treatment and longer treatment duration significantly decreased the risk of developing cirrhosis and HCC. HBsAg loss seemed to be a protective factor for cirrhosis/HCC in NAs-treated patients with CHB, and cirrhosis was a confirmed risk factor for HCC development as expected.
Optimizing the dietary calcium (Ca) level is essential to maximize the eggshell quality, egg production and bone formation in poultry. This study aimed to establish the Ca requirements of egg-type duck breeders from 23 to 57 weeks of age on egg production, eggshell, incubation, tibial, plasma and ovary-related indices, as well as the expression of matrix protein-related genes. Totally, 450 Longyan duck breeders aged 21 weeks of age were allotted randomly into five treatments, each with six replicates of 15 individually caged birds. The data collection started from 23 weeks of age and continued over the following 35 weeks. The five groups corresponded to five dietary treatments containing either 2.8%, 3.2%, 3.6%, 4.0% or 4.4% Ca. The tested dietary Ca levels increased (linear, P <0.01) egg production and egg mass, and linearly improved (P <0.01) the feed conversion ratio (FCR). Increasing the dietary Ca levels from 2.8% to 4.4% increased (P <0.01) the eggshell thickness and eggshell content. The tested Ca levels showed a quadratic effect on eggshell thickness and ovarian weight (P <0.01); the highest values were obtained with the Ca levels 4.0% and 3.6%, respectively. Dietary Ca levels affected the small yellow follicles (SYF) number and SYF weight/ovarian weight, and the linear response (P <0.01) was significant vis-à-vis SYF number. In addition, dietary Ca levels increased (P <0.05) the tibial dry weight, breaking strength, mineral density and ash content. Plasma and tibial phosphorus concentration exhibited a quadratic (P <0.01) response to dietary Ca levels. Plasma calcitonin concentration linearly (P <0.01) increased as dietary Ca levels increased. The relative expression of carbonic anhydrase 2 in the uterus rose (P <0.01) with the increment of dietary Ca levels, and the highest value was obtained with 3.2% Ca. In conclusion, Longyan duck breeders fed a diet with 4.0% Ca had superior eggshell and tibial quality, while those fed a diet with 3.6% Ca had the heaviest ovarian weights. The regression model indicated that the dietary Ca levels 3.86%, 3.48% and 4.00% are optimal levels to obtain maximum eggshell thickness, ovarian weight and tibial mineral density, respectively.
Co-receptor tropism has been identified to correlate with HIV-1 transmission and the disease progression in patients. A molecular epidemiology investigation of co-receptor tropism is important for clinical practice and effective control of HIV-1. In this study, we investigated the co-receptor tropism on HIV-1 variants of 85 antiretroviral-naive patients with Geno2pheno algorithm at a false-positive rate of 10%. Our data showed that a majority of the subjects harboured the CCR5-tropic virus (81.2%, 69/85). No significant differences in gender, age, baseline CD4+ T-cell counts and transmission routes were observed between subjects infected with CXCR4-tropic or CCR5-tropic virus. The co-receptor tropism appeared to be associated with the virus genotype; a significantly more CXCR4-use was predicted in CRF01_AE infections whereas all CRF07_BC and CRF08_BC were predicted to use CCR5 co-receptor. Sequences analysis of V3 revealed a higher median net charge in the CXCR4 viruses over CCR5 viruses (4.0 vs. 3.0, P < 0.05). The predicted N-linked glycosylation site between amino acids 6 and 8 in the V3 region was conserved in CCR5 viruses, but not in CXCR4 viruses. Besides, variable crown motifs were observed in both CCR5 and CXCR4 viruses, of which the most prevalent motif GPGQ existed in both viral tropism and almost all genotypes identified in this study except subtype B. These findings may offer important implications for clinical practice and enhance our understanding of HIV-1 biology.
Laser–solid interactions are highly suited as a potential source of high energy X-rays for nondestructive imaging. A bright, energetic X-ray pulse can be driven from a small source, making it ideal for high resolution X-ray radiography. By limiting the lateral dimensions of the target we are able to confine the region over which X-rays are produced, enabling imaging with enhanced resolution and contrast. Using constrained targets we demonstrate experimentally a
X-ray source, improving the image quality compared to unconstrained foil targets. Modelling demonstrates that a larger sheath field envelope around the perimeter of the constrained targets increases the proportion of electron current that recirculates through the target, driving a brighter source of X-rays.
The second Singapore Mental Health Study (SMHS) – a nationwide, cross-sectional, epidemiological survey - was initiated in 2016 with the intent of tracking the state of mental health of the general population in Singapore. The study employed the same methodology as the first survey initiated in 2010. The SMHS 2016 aimed to (i) establish the 12-month and lifetime prevalence and correlates of major depressive disorder (MDD), dysthymia, bipolar disorder, generalised anxiety disorder (GAD), obsessive compulsive disorder (OCD) and alcohol use disorder (AUD) (which included alcohol abuse and dependence) and (ii) compare the prevalence of these disorders with reference to data from the SMHS 2010.
Door-to-door household surveys were conducted with adult Singapore residents aged 18 years and above from 2016 to 2018 (n = 6126) which yielded a response rate of 69.0%. The subjects were randomly selected using a disproportionate stratified sampling method and assessed using World Health Organization Composite International Diagnostic Interview version 3.0 (WHO-CIDI 3.0). The diagnoses of lifetime and 12-month selected mental disorders including MDD, dysthymia, bipolar disorder, GAD, OCD, and AUD (alcohol abuse and alcohol dependence), were based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria.
The lifetime prevalence of at least one mood, anxiety or alcohol use disorder was 13.9% in the adult population. MDD had the highest lifetime prevalence (6.3%) followed by alcohol abuse (4.1%). The 12-month prevalence of any DSM-IV mental disorders was 6.5%. OCD had the highest 12-month prevalence (2.9%) followed by MDD (2.3%). Lifetime and 12-month prevalence of mental disorders assessed in SMHS 2016 (13.8% and 6.4%) was significantly higher than that in SMHS 2010 (12.0% and 4.4%). A significant increase was observed in the prevalence of lifetime GAD (0.9% to 1.6%) and alcohol abuse (3.1% to 4.1%). The 12-month prevalence of GAD (0.8% vs. 0.4%) and OCD (2.9% vs. 1.1%) was significantly higher in SMHS 2016 as compared to SMHS 2010.
The high prevalence of OCD and the increase across the two surveys needs to be tackled at a population level both in terms of creating awareness of the disorder and the need for early treatment. Youth emerge as a vulnerable group who are more likely to be associated with mental disorders and thus targeted interventions in this group with a focus on youth friendly and accessible care centres may lead to earlier detection and treatment of mental disorders.
Hematite (α-Fe2O3) powder compacts have been subjected to controlled, quantitative high pressure shock loading at peak pressures from 8-27 GPa and preserved for post shook analysis. The broadened x-ray diffraction peak profiles have been analyzed to determine the residual lattice strain and the coherent crystallite sizes. Maximum modification effects are observed near 17 GPa with strain values near 3 x 10-3 and size values near 200 Å suggesting annealing at higher shock pressure, resulting from the higher shock temperature.
The aim of the study was to investigate any association between extrauterine growth restriction (EUGR) and intestinal flora of <30-week-old preterm infants. A total of 59 preterm infants were assigned to EUGR (n=23) and non-EUGR (n=36) groups. Intestinal bacteria were compared by using high-throughput sequencing of bacterial rRNA. The total abundance of bacteria in 344 genera (7568 v. 13,760; P<0.0001) and 456 species (10,032 v. 18,240; P<0.0001) was significantly decreased in the EUGR group compared with the non-EUGR group. After application of a multivariate logistic model and adjusting for potential confounding factors, as well as false-discovery rate corrections, we found four bacterial genera with higher and one bacterial genus with lower abundance in the EUGR group compared with the control group. In addition, the EUGR group showed significantly increased abundances of six species (Streptococcus parasanguinis, Bacterium RB5FF6, two Klebsiella species and Microbacterium), but decreased frequencies of three species (one Acinetobacter species, Endosymbiont_of_Sphenophorus_lev and one Enterobacter_species) compared with the non-EUGR group. Taken together, there were significant changes in the intestinal microflora of preterm infants with EUGR compared to preterm infants without EUGR.
Muons produced by the Bethe–Heitler process from laser wakefield accelerated electrons interacting with high
materials have velocities close to the laser wakefield. It is possible to accelerate those muons with laser wakefield directly. Therefore for the first time we propose an all-optical ‘Generator and Booster’ scheme to accelerate the produced muons by another laser wakefield to supply a prompt, compact, low cost and controllable muon source in laser laboratories. The trapping and acceleration of muons are analyzed by one-dimensional analytic model and verified by two-dimensional particle-in-cell (PIC) simulation. It is shown that muons can be trapped in a broad energy range and accelerated to higher energy than that of electrons for longer dephasing length. We further extrapolate the dependence of the maximum acceleration energy of muons with the laser wakefield relativistic factor
and the relevant initial energy
. It is shown that a maximum energy up to 15.2 GeV is promising with
on the existing short pulse laser facilities.
The mechanical properties of thin-walled plate with close-packed film cooling holes are studied based on the equivalent solid material concept. The equivalent principals of the method of equivalent strain energy, homogenization theory and uniform static deformation are considered. A simplification method of square penetration pattern for pitch and diagonal direction loading is presented. The goodness of fit is calculated to determine the optimal method. The tensile deformation, bending deflection, rotation displacement and maximum Mises equivalent stress of simplification plate models are in good agreement with plate models with close-packed film cooling holes. For square penetration pattern for pitch direction loading, the equivalent errors of Mises equivalent stress are all less than 10% when the ligament efficiency is more than 0.6.
β-Casomorphin is an opioid-like bioactive peptide derived from β-casein of milk that plays a crucial role in modulating animal’s feed intake, growth, nutrient utilization and immunity. However, the effect of β-casomorphin on lipid metabolism in chickens and its mechanism remain unclear. The aim of this study was to investigate the effects of β-casomorphin on fat deposition in broiler chickens and explore its mechanism of action. A total of 120 21-day-old Arbor Acres male broilers (747.94±8.85 g) was chosen and randomly divided into four groups with six replicates of five birds per replicate. Three groups of broilers were injected with 0.1, 0.5 or 1.0 mg/kg BW of β-casomorphin in 1 ml saline for 7 days, whereas the control group received 1 ml saline only. The results showed that subcutaneous administration of β-casomorphin to broiler chickens increased average daily gain, average daily feed intake and fat deposition, and decreased feed : gain ratio (P<0.05). The activity of malate dehydrogenase in the pectoral muscle, liver and abdominal adipose tissue was also increased along with the concentrations of insulin, very-low-density lipoprotein and triglyceride in the plasma (P<0.05). The activity of hormone-sensitive lipase in the liver and abdominal adipose tissue and the concentration of glucagon in the plasma were decreased by injection with β-casomorphin (P<0.05). Affymetrix gene chip analysis revealed that administering 1.0 mg/kg BW β-casomorphin caused differential expression of 168 genes in the liver with a minimum of fourfold difference. Of those, 37 genes are directly involved in lipid metabolism with 18 up-regulated genes such as very low density lipoprotein receptor gene and fatty acid synthase gene, and 19 down-regulated genes such as lipoprotein lipase gene and low density lipoprotein receptor gene. In conclusion, β-casomorphin increased growth performance and fat deposition of broilers. Regulation of fat deposition by β-casomorphin appears to take place through changes in hormone secretion and enzyme activities by controlling the gene expression of lipid metabolism and feed intake, increasing fat synthesis and deposition.