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While child self-regulation is shaped by the environment (e.g., the parents’ caregiving behaviors), children also play an active role in influencing the care they receive, indicating that children's individual differences should be integrated in models relating early care to children's development. We assessed 409 children's observed temperamental behavioral inhibition (BI), effortful control (EC), and the primary caregiver's parenting at child ages 3 and 5. Parents reported on child behavior problems at child ages 3, 5, and 8. Mediation analyses were conducted to examine relations between child temperament and parenting in predicting child problems. BI at age 3 was positively associated with structured parenting at age 5, which was negatively related to child internalizing and attention-academic problems at age 8. In contrast, parenting at child age 3 did not predict child BI or EC at age 5, nor did age 3 EC predict parenting at age 5. Findings indicate that child behavior may shape the development of caregiving and, in turn, long-term child adjustment, suggesting that studies of caregiving and child outcomes should consider the role of child temperament toward developing more informative models of child–environment interplay.
The development and subsistence strategies adopted in ancient settlements are crucial to the understanding of long-term human–environmental interaction in the past. Here, we reassess the chronology of the ancient walled settlement of Sanjiao in the Hexi Corridor in northwestern China through accelerator mass spectrometry radiocarbon (AMS 14C) dating and explore the subsistence of the settlers inside through the identification of carbonized seeds and charcoal. In addition, high-resolution paleoclimate records in the Hexi Corridor and nearby regions are employed to explore the reason for the construction of Sanjiao. Our results show that Sanjiao was built around 828 cal BC and remained inhabited through 384–116 cal BC. This indicates Sanjiao is the earliest known walled settlement in the Hexi Corridor. Ancient people at Sanjiao consumed crops such as barley, broomcorn millet, and foxtail millet, and used wood from Tamarix chinensis, Tamarix, Salix, Picea, Hippophae, Betulaceae, and Poaceae as fuel. The construction date of Sanjiao correlates with climate deterioration and social upheavals in the Hexi Corridor, potentially suggesting a defensive purpose for the site.
While assessing the environmental impact of nuclear power plants, researchers have focused their attention on radiocarbon (14C) owing to its high mobility in the environment and important radiological impact on human beings. The 10 MW high-temperature gas-cooled reactor (HTR-10) is the first pebble-bed gas-cooled test reactor in China that adopted helium as primary coolant and graphite spheres containing tristructural-isotropic (TRISO) coated particles as fuel elements. A series of experiments on the 14C source terms in HTR-10 was conducted: (1) measurement of the specific activity and distribution of typical nuclides in the irradiated graphite spheres from the core, (2) measurement of the activity concentration of 14C in the primary coolant, and (3) measurement of the amount of 14C discharged in the effluent from the stack. All experimental data on 14C available for HTR-10 were summarized and analyzed using theoretical calculations. A sensitivity study on the total porosity, open porosity, and percentage of closed pores that became open after irradiating the matrix graphite was performed to illustrate their effects on the activity concentration of 14C in the primary coolant and activity amount of 14C in various deduction routes.
With the aims of overcoming the limitations of the existing basic flow model derived from an axisymmetric generating body and extending the aerodynamic design method of the airframe/inlet integrated waverider vehicle, this study develops an upgraded basic flow model derived from an axisymmetric shock wave. It then upgrades the design method for airframe/inlet integration of an air-breathing hypersonic waverider vehicle, which is termed the ‘full-waverider vehicle’ in this study. In this paper, first, the design principle and method for the upgraded full-waverider vehicle derived from an axisymmetric basic shock wave are described in detail. Second, an upgraded basic flow model that accounts for both internal and external flows is derived from an axisymmetric basic shock wave by use of both the streamline tracing method and the method of characteristics (MOC). Third, the upgraded full-waverider vehicle is developed from the upgraded basic flow model by the streamline tracing method. Fourth, the design theories and methodologies of both the upgraded basic flow model and the upgraded full-waverider vehicle are validated by a numerical computation method. Finally, the aerodynamic performances and viscous effects of both the upgraded basic flow model and the upgraded full-waverider vehicle are analysed by numerical computation. The obtained results show that the upgraded basic flow model and aerodynamic design method are effective for the design of the airframe/inlet integration of an air-breathing hypersonic waverider vehicle.
Force-feeding was considered as a traditional high-efficiency approach to improve growth performance and accelerate fat deposition of Pekin ducks. However, force-feeding is a serious violation of international advocacy on animal welfare, because it can induce serious injuries to animals, such as damages to the digestive tract, effects on immunity and even severe oxidative stress. Therefore, it is urgent to stop force-feeding. The aim of this study was to determine the effects of force feeding on immune function, digestive function and oxidative stress in the mucosa of duodenum and jejunum of Pekin ducks. A total of 500 ducks were randomly divided into two groups. The control group was allowed to feed freely on a basal diet. The experimental group was force-fed by inserting a plastic feeding tube 8 to 10 inches long down the esophagus for 6 days. Compared with the control group, there was a significant (P<0.05) increase in serum diamine oxidase, d-lactic acid, endotoxin and corticosterone levels in the force-feeding group. The crypt depth in duodenum and jejunum showed significant differences (P<0.05) between the two groups and the intestinal villus epithelium cell was severely damaged in force-feeding group. Similarly, the activities of digestive enzymes as well as the levels of immune function in the duodenal and jejunal mucosa in the force-feeding group were significantly higher than the control group (P<0.05). However, there was a significant decrease in the superoxide dismutase, glutathione peroxidase and catalase levels with a marked increase in malondialdehyde level in duodenal and jejunal mucosa (P<0.05). In summary, at the end of the fattening period with force-feeding for 6 days, Pekin ducks experienced an adverse effect on the integrity of their duodenal and jejunal mucosa epithelium cell as well as their immune function and antioxidant capacity of Pekin ducks but also had improvement in digestive enzyme activities.
Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus (MRSA) have been considered prevalent pathogens in foot infections. However, whether empiric therapy directed against these organisms is necessary, and in whom to consider treatment, is rather unclear. The aim of this study was to develop predictive algorithms for forecasting the probability of isolating these organisms in the infected wounds of patients in a population where the prevalence of resistant pathogens is low. This was a retrospective study of regression model-based risk factor analysis that included 140 patients who presented with infected, culture positive foot ulcers to two urban hospitals. A total of 307 bacteria were identified, most frequently MRSA (11.1%). P. aeruginosa prevalence was 6.5%. In the multivariable analysis, amputation (odds ratio (OR) 5.75, 95% confidence interval (CI) 1.48–27.63), renal disease (OR 5.46, 95% CI 1.43–25.16) and gangrene (OR 2.78, 95% CI 0.82–9.59) were identified as risk factors associated with higher while diabetes (OR 0.07, 95% CI 0.01–0.34) and Infectious Diseases Society of America infection severity >3 (OR 0.18, 95% CI 0.03–0.65) were associated with lower odds of P. aeruginosa isolation (C statistic 0.81). Similar analysis for MRSA showed that amputation was associated with significantly lower (OR 0.29, 95% CI 0.09–0.79) risk, while history of MRSA infection (OR 5.63, 95% CI 1.56–20.63) and osteomyelitis (OR 2.523, 95% CI 1.00–6.79) was associated with higher odds of isolation (C statistic 0.69). We developed two predictive nomograms with reasonable to strong ability to discriminate between patients who were likely of being infected with P. aeruginosa or MRSA and those who were not. These analyses confirm the association of some, but also question the significance of other frequently described risk factors in predicting the isolation of these organisms.
To investigate the effects of friendly competition on hand hygiene compliance as part of a multimodal intervention program.
Prospective observational study in which the primary outcome was hand hygiene compliance. Differences were analyzed using the Pearson χ2 test. Odds ratios (ORs) with 95% confidence interval were calculated using multilevel logistic regression.
Observations were performed in 9 public hospitals and 1 rehabilitation center in Rotterdam, Netherlands.
From 2014 to 2016, at 5 time points (at 6-month intervals) in 120 hospital wards, 20,286 hand hygiene opportunities were observed among physicians, nurses, and other healthcare workers (HCWs).
The multimodal, friendly competition intervention consisted of mandatory interventions: monitoring and feedback of hand hygiene compliance and optional interventions (ie, e-learning, kick-off workshop, observer training, and team training). Hand hygiene opportunities, as formulated by the World Health Organization (WHO), were unobtrusively observed at 5 time points by trained observers. Compliance data were presented to the healthcare organizations as a ranking.
The overall mean hand hygiene compliance at time point 1 was 42.9% (95% confidence interval [CI], 41.4–44.4), which increased to 51.4% (95% CI, 49.8–53.0) at time point 5 (P<.001). Nurses showed a significant improvement between time points 1 and 5 (P<.001), whereas the compliance of physicians and other HCWs remained unchanged. In the multilevel logistic regressions, time points, type of ward, and type of HCW showed a significant association with compliance.
Between the start and the end of the multimodal intervention program in a friendly competition setting, overall hand hygiene compliance increased significantly.
Heading date (HD) and flowering date (FD) are critical for yield potential and stability, so understanding their genetic foundation is of great significance in wheat breeding. Three related recombinant inbred line populations with a common female parent were developed to identify quantitative trait loci (QTL) for HD and FD in four environments. In total, 25 putative additive QTL and 20 pairwise epistatic effect QTL were detected in four environments. The additive QTL were distributed across 17 wheat chromosomes. Of these, QHd-1A, QHd-1D, QHd-2B, QHd-3B, QHd-4A, QHd-4B and QHd-6D were major and stable QTL for HD. QFd-1A, QFd-2B, QFd-4A and QFd-4B were major and stable QTL for FD. In addition, an epistatic interaction test showed that epistasis played important roles in controlling wheat HD and FD. Genetic relationships between HD/FD and five yield-related traits (YRTs) were characterized and ten QTL clusters (C1–C10) simultaneously controlling YRTs and HD/FD were identified. The present work laid a genetic foundation for improving yield potential in wheat molecular breeding programmes.
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.
Although application of organic fertilizers has become a recommended way for developing sustainable agriculture, it is still unclear whether above-ground and below-ground crops have similar responses to chemical fertilizers (CF) and organic manure (OM) under the same farming conditions. The current study investigated soil quality and crop yield response to fertilization of a double-cropping system with rapeseed (above-ground) and sweet potato (below-ground) in an infertile red soil for 2 years (2014–16). Three fertilizer treatments were compared, including CF, OM and organic manure plus chemical fertilizer (MCF). Organic fertilizers (OM and MCF) increased the yield of both above- and below-ground crops and improved soil biochemical properties significantly. The current study also found that soil-chemical properties were the most important and direct factors in increasing crop yields. Also, crop yield was affected indirectly by soil-biological properties, because no significant effects of soil-biological activities on yield were detected after controlling the positive effects of soil-chemical properties. Since organic fertilizers could not only increase crop yield, but also improve soil nutrients and microbial activities efficiently and continuously, OM application is a reliable agricultural practice for both above- and below-ground crops in the red soils of China.
During a study of the ore minerals belonging to the recently discovered Shuangjianzishan Ag–Pb–Zn deposit in NE China, we have discovered exceptional selenium enrichment in canfieldite (up to 11.6 wt.% of Se). Incorporation of Se into canfieldite has been investigated by an integrated approach using field emission scanning electron microscopy, electron microprobe and single-crystal X-ray diffraction. Canfieldite has been identified as one of the dominant Ag-bearing ore minerals in the studied deposit, which occurs mostly in slate-hosted vein type Ag–Pb–Zn ore bodies. Selenium is either homogeneously or, remarkably, heterogeneously distributed in the different canfieldite fragments studied. Chemical variations of Se are mostly attributable to a series of retrograde reactions resulting in diverse decomposition and exsolution of primary phases during cooling, or alternatively, related to influxes of Se-rich fluids during the formation of canfieldite. To evaluate the effects of the Se-for-S substitution in the structure, a crystal of Se-rich canfieldite [Ag7.98Sn1.02(S4.19Se1.81)Σ6.00] was investigated. The unit-cell parameters are: a = 10.8145(8) Å and V = 1264.8(3) Å3. The structure was refined in the space group F
3m to R1 = 0.0315 for 194 independent reflections, with 20 parameters. The crystal structure of Se-rich canfieldite was found to be topologically identical to that of pure canfieldite. If the short Ag–Ag contacts are ignored (due to the disorder), the two Ag atoms in the structure can be considered as three-fold (Ag1) and four-fold (Ag2) coordinated. Tin adopts a regular tetrahedral coordination. As in the case of Te-rich canfieldite, the refinement of the site-occupancy factor indicates that Se is disordered over the three anion positions.
Active drag reduction of an Ahmed body with a slant angle of
, corresponding to the high-drag regime, has been experimentally investigated at Reynolds number
, based on the square root of the model cross-sectional area. Four individual actuations, produced by steady blowing, are applied separately around the edges of the rear window and vertical base, producing a drag reduction of up to 6–14 %. However, the combination of the individual actuations results in a drag reduction 29 %, higher than any previous drag reductions achieved experimentally and very close to the target (30 %) set by automotive industries. Extensive flow measurements are performed, with and without control, using force balance, pressure scanner, hot-wire, flow visualization and particle image velocimetry techniques. A marked change in the flow structure is captured in the wake of the body under control, including the flow separation bubbles, over the rear window or behind the vertical base, and the pair of C-pillar vortices at the two side edges of the rear window. The change is linked to the pressure rise on the slanted surface and the base. The mechanisms behind the effective control are proposed. The control efficiency is also estimated.
Plant nitrogen (N) links with many physiological progresses of crop growth and yield formation. Accurate simulation is key to predict crop growth and yield correctly. The aim of the current study was to improve the estimation of N uptake and translocation processes in the whole rice plant as well as within plant organs in the RiceGrow model by using plant and organ maximum, critical and minimum N dilution curves. The maximum and critical N (Nc) demand (obtained from the maximum and critical curves) of shoot and root and Nc demand of organs (leaf, stem and panicle) are calculated by N concentration and biomass. Nitrogen distribution among organs is computed differently pre- and post-anthesis. Pre-anthesis distribution is determined by maximum N demand with no priority among organs. In post-anthesis distribution, panicle demands are met first and then the remaining N is allocated to other organs without priority. The amount of plant N uptake depends on plant N demand and N supplied by the soil. Calibration and validation of the established model were performed on field experiments conducted in China and the Philippines with varied N rates and N split applications; results showed that this improved model can simulate the processes of N uptake and translocation well.
Much of the interest in youth at clinical high risk (CHR) of psychosis has been in understanding conversion. Recent literature has suggested that less than 25% of those who meet established criteria for being at CHR of psychosis go on to develop a psychotic illness. However, little is known about the outcome of those who do not make the transition to psychosis. The aim of this paper was to examine clinical symptoms and functioning in the second North American Prodrome Longitudinal Study (NAPLS 2) of those individuals whose by the end of 2 years in the study had not developed psychosis.
In NAPLS-2 278 CHR participants completed 2-year follow-ups and had not made the transition to psychosis. At 2-years the sample was divided into three groups – those whose symptoms were in remission, those who were still symptomatic and those whose symptoms had become more severe.
There was no difference between those who remitted early in the study compared with those who remitted at one or 2 years. At 2-years, those in remission had fewer symptoms and improved functioning compared with the two symptomatic groups. However, all three groups had poorer social functioning and cognition than healthy controls.
A detailed examination of the clinical and functional outcomes of those who did not make the transition to psychosis did not contribute to predicting who may make the transition or who may have an earlier remission of attenuated psychotic symptoms.
Cultivated pastures in southern China are being used to improve forage productivity and animal performance, but studies on grazing behaviour of goats in these cultivated pastures are still rare. In the current study, the grazing behaviour of Yunling black goats under low (5 goats/ha) and high (15 goats/ha) stocking rates (SRs) was evaluated. Data showed that the proportion of time goats spent on activities was: eating (0.59–0.87), ruminating (0.05–0.35), walking (0.03–0.06) and resting (0.01–0.03). Compared with low SR, goats spent more time eating and walking, and less time ruminating and resting under high SR. Goats had similar diet preferences under both SR and preferred to eat grasses (ryegrass and cocksfoot) more than a legume (white clover). The distribution of eating time on each forage species was more uniform under high v. low SR. Bites/step, bite weight and daily intake were greater under low than high SR. Results suggest that the SR affects grazing behaviour of goats on cultivated pasture, and identifying an optimal SR is critical for increasing bite weight and intake.
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.
Layered transition metal dichalcogenides (TMDs) have attracted interest due to their promise for future electronic and optoelectronic technologies. As one approaches the two-dimensional (2D) limit, thickness and local topology can greatly influence the macroscopic properties of a material. To understand the unique behavior of TMDs it is therefore important to identify the number of atomic layers and their stacking in a sample. The goal of this work is to extract the thickness and stacking sequence of TMDs directly by matching experimentally recorded high-angle annular dark-field scanning transmission electron microscope images and convergent-beam electron diffraction (CBED) patterns to quantum mechanical, multislice scattering simulations. Advantageously, CBED approaches do not require a resolved lattice in real space and are capable of neglecting the thickness contribution of amorphous surface layers. Here we demonstrate the crystal thickness can be determined from CBED in exfoliated 1T-TaS2 and 2H-MoS2 to within a single layer for ultrathin ≲9 layers and ±1 atomic layer (or better) in thicker specimens while also revealing information about stacking order—even when the crystal structure is unresolved in real space.