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Recently, we found that in ovo feeding of l-leucine (l-Leu) afforded thermotolerance, stimulated lipid metabolism and modified amino acid metabolism in male broiler chicks. However, the effects of in ovo feeding of l-Leu on thermoregulation and growth performance until marketing age of broilers are still unknown. In this study, we investigated the effects of in ovo feeding of l-Leu on body weight (BW) gain under control thermoneutral temperature or chronic heat stress. We measured changes of body temperature and food intake, organ weight, as well as amino acid metabolism and plasma metabolites under acute and chronic heat stress in broilers. A total of 168 fertilized Chunky broiler eggs were randomly divided into 2 treatment groups in experiments. The eggs were in ovo fed with l-Leu (34.5 µmol/500 µl per egg) or sterile water (500 µl/egg) during incubation. After hatching, male broilers were selected and assigned seven to nine replicates (one bird/replicate) in each group for heat challenge experiments. Broilers (29- or 30-day-old) were exposed to acute heat stress (30 ± 1°C) for 120 min or a chronic heat cyclic and continued heat stress (over 30 ± 1°C; ages, 15 to 44 days). In ovo feeding of l-Leu caused a significant suppression of enhanced body temperature without affecting food intake, plasma triacylglycerol, non-esterified fatty acids, ketone bodies, glucose, lactic acid or thyroid hormones under acute heat stress. Daily body temperature was significantly increased by l-Leu in ovo feeding under chronic heat stress. Interestingly, in ovo feeding of l-Leu caused a significantly higher daily BW gain compared with that of the control group under chronic heat stress. Moreover, some essential amino acids, including Leu and isoleucine, were significantly increased in the liver and decreased in the plasma by l-Leu in ovo feeding under acute heat stress. These results suggested that l-Leu in ovo feeding afforded thermotolerance to broilers under acute heat stress mainly through changing amino acid metabolism until marketing age.
We present ALMA band 7 data of the extreme OH/IR star, OH 26.5+0.6. In addition to lines of CO and its isotopologues, the circumstellar envelope also exhibits a number of emission lines due to metal-containing molecules, e.g., NaCl and KCl. A lack of C18O is expected, but a non-detection of C17O is puzzling given the strengths of H217O in Herschel spectra of the star. However, a line associated with Si17O is detected. We also report a tentative detection of a gas-phase emission line of MgS. The ALMA spectrum of this object reveals intriguing features which may be used to investigate chemical processes and dust formation during a high mass-loss phase.
Multiple human immunodeficiency virus (HIV)-1 genotypes in China were first discovered in Yunnan Province before disseminating throughout the country. As the HIV-1 epidemic continues to expand in Yunnan, genetic characteristics and transmitted drug resistance (TDR) should be further investigated among the recently infected population. Among 2828 HIV-positive samples newly reported in the first quarter of 2014, 347 were identified as recent infections with BED-captured enzyme immunoassay (CEIA). Of them, 291 were successfully genotyped and identified as circulating recombinant form (CRF)08_BC (47.4%), unique recombinant forms (URFs) (18.2%), CRF01_AE (15.8%), CRF07_BC (14.4%), subtype C (2.7%), CRF55_01B (0.7%), subtype B (0.3%) and CRF64_BC (0.3%). CRF08_BC and CRF01_AE were the predominant genotypes among heterosexual and homosexual infections, respectively. CRF08_BC, URFs, CRF01_AE and CRF07_BC expanded with higher prevalence in central and eastern Yunnan. The recent common ancestor of CRF01_AE, CRF07_BC and CRF08_BC dated back to 1983.1, 1992.1 and 1989.5, respectively. The effective population sizes (EPS) for CRF01_AE and CRF07_BC increased exponentially during 1991–1999 and 1994–1999, respectively. The EPS for CRF08_BC underwent two exponential growth phases in 1994–1998 and 2001–2002. Lastly, TDR-associated mutations were identified in 1.8% of individuals. These findings not only enhance our understanding of HIV-1 evolution in Yunnan but also have implications for vaccine design and patient management strategies.
Obsessive–compulsive disorder (OCD) has been associated with abnormal cognitive and emotional functions and these dysfunctions may be dependent on the disruption of dynamic interactions within neuronal circuits associated with emotion regulation. Although several studies have shown the aberrant cognitive–affective processing in OCD patients, little is known about how to characterize effective connectivity of the disrupted neural interactions. In the present study, we applied effective connectivity analysis using dynamic causal modeling to explore the disturbed neural interactions in OCD patients.
A total of 20 patients and 21 matched healthy controls performed a delayed-response working memory task under emotional or non-emotional distraction while undergoing functional magnetic resonance imaging.
During the delay interval under negative emotional distraction, both groups showed similar patterns of activations in the amygdala. However, under negative emotional distraction, the dorsolateral prefrontal cortex (DLPFC) and the orbitofrontal cortex (OFC) exhibited significant differences between groups. Bayesian model averaging indicated that the connection from the DLPFC to the OFC was negatively modulated by negative emotional distraction in patients, when compared with healthy controls (p < 0.05, Bonferroni-corrected).
Exaggerated recruitment of the DLPFC may induce the reduction of top-down prefrontal control input over the OFC, leading to abnormal cortico-cortical interaction. This disrupted cortico-cortical interaction under negative emotional distraction may be responsible for dysfunctions of cognitive and emotional processing in OCD patients and may be a component of the pathophysiology associated with OCD.
The objective of this study was to investigate the effects of maternal protein or energy restriction on hormonal and metabolic status of pregnant goats during late gestation and their postnatal male kids. Forty-five pregnant goats were fed a control (CON), 40% protein-restricted (PR) or 40% energy-restricted (ER) diet from 90 days of gestation until parturition. Plasma of mothers (90, 125 and 145 days of gestation) and kids (6 weeks of age) were sampled to determine metabolites and hormones. Glucose concentration for pregnant goats subjected to PR or ER was less (P<0.001) than that of CON goats at 125 and 145 days of gestation. However, plasma nonesterified fatty acids concentration was greater (P<0.01) at 125 and 145 days for PR and ER than CON. Protein restriction increased (P<0.01) maternal cortisol concentration by 145 days of gestation, and ER decreased (P<0.01) maternal insulin concentration at 125 days of gestation. Moreover, maternal amino acid (AA) concentrations were affected by nutritional restriction, with greater (P<0.05) total AA (TAA) and nonessential AA (NEAA) for PR goats but less (P<0.05) TAA and NEAA for ER goats at 125 days of gestation. After 6 weeks of nutritional recovery, plasma concentrations of most metabolic and hormonal parameters in restricted kids were similar to CON kids, except for reduced (P<0.05) insulin concentration in ER, and reduced (P<0.05) Asp concentration in PR and ER kids. These results provide information on potential metabolic mechanisms responsible for fetal programming.
Batch cultures of mixed rumen micro-organisms were used to evaluate varying enzyme products with high xylanase activity (EPX), four of which were recombinant single xylanase activity developmental enzyme products (EPX1–EPX4, products of xylanase genes derived from Trichoderma harzianum, Trichoderma reesei, Orpinomyces and Aspergillus oryzae, respectively), for their potential to improve in vitro ruminal fermentation of three forages [maize (Zea mays) stover (MS), rice (Oryza sativa) straw (RS) and Guimu No. 1 grass (Pennisetum americanum×Pennisetum purpureum, GM)]. The enzyme product EPX5, derived from Trichoderma longibrachiatum, was used as a positive control that could improve in vitro fermentation of forages. Enzymes were supplied at dose rates of 0 (control), 20 (low), 50 (medium) and 80 (high) enzymic units of xylanase/g of dry matter (DM). There were no interactions between EPX and dose for the fermentation characteristics evaluated. Increasing EPX dose linearly increased gas production (GP) kinetic characters [i.e. asymptotic GP (VF), half time when GP is half of the theoretical maximum GP (t0·5), and initial fractional rate of degradation (FRD0)] and methane (CH4) production from RS and GM at 24 h, and increased degradability of DM at 24 h for MS and RS. A linear increase in degradability of neutral detergent fibre (NDF) of the three forages at 24 h was observed with increasing dose of EPX, but at 48 h only NDF degradability of RS was increased. There were differences in the effects of EPX on degradability of DM and NDF from RS at 24 h, with EPX4 having the highest and EPX1 having the lowest. In addition, increasing EPX dose linearly increased acetate proportion at 24 h and total volatile fatty acids (TVFA) at 48 h in MS. Increasing EPX dose linearly increased TVFA at 24 h, and ammonia-nitrogen (NH3-N) concentration at 48 h in RS. For GM, linear or quadratic effects of dose on acetate and butyrate concentration were observed at 24 and 48 h. The present study indicates that applying EPX to low-quality forages has the potential to improve rumen degradability and utilization. Furthermore, EPX from different sources differed in their effects when applied at the same dose rate, with the responses being forage-specific. For RS, the EPX derived from A. oryzae showed the greatest positive effects on forage degradation; whereas for MS and GM, the source of micro-organism where EPX gene was derived did not affect the degradation, with little difference among the EPX evaluated.
Pedogenic alteration of illite from red earth sediments in Jiujiang in subtropical China was investigated using X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). Illite, hydroxy-interlayered vermiculite (HIV), kaolinite and mixed-layer illite-HIV (I-HIV) are present in the soils. The characteristic reflections of the clay phases were 14 Å, 10–14 Å, 10 Å, and 7 Å, respectively. After Mg-glycerol saturations, the 14 Å peak of the samples did not expand, and after heating at 350°C and 550°C it shifted to 13.8 Å and 12 Å respectively, with no residual 14 Å reflection, suggesting the occurrence of hydroxy-interlayered vermiculite. The randomly interstratified I-HIV clays were characterized by a broad peak at 10–14 Å, which did not change its position after Mg-glycerol saturation, but collapsed to 10 Å after heating at 350°C and 550°C. HRTEM analysis showed different lattice fringes of 12 Å, 10 Å and 7 Å . Mixed-layer I-HIV, HIV-K and illite-kaolinite (I-K) were observed in the HRTEM images which represented the intermediate phases during illite alteration. The merging of two 10 Å illite layers into a 12 Å HIV layer, lateral transformation of one HIV layer into one kaolinite layer and alteration of one illite layer into two kaolinite layers illustrated the mechanisms of illite-to-HIV, HIV-to-kaolinite and illite-tokaolinite transformation, respectively. The proposed pedogenic alteration of illite and the weathering sequence of the clay minerals in Jiujiang is illite → I-HIV → HIV → HIV-K → kaolinite. In addition, illite may transform directly to kaolinite.
While demand response has achieved promising results on making the power grid more efficient and reliable, the additional dynamics and flexibility brought by demand response also increase the uncertainty and complexity of the centralized load forecast. In this paper, we propose a game-theoretic demand response scheme that can transform the traditional centralized load prediction structure into a distributed load prediction system by the participation of customers. Moreover, since customers are generally rational and thus naturally selfish, they may cheat if cheating can improve their payoff. Therefore, enforcing truth-telling is crucial. We prove analytically and demonstrate with simulations that the proposed game-theoretic scheme is incentive compatible, i.e., all customers are motivated to report and consume their true optimal demands and any deviation will lead to a utility loss. We also prove theoretically that the proposed demand response scheme can lead to the solution that maximizes social welfare and is proportionally fair in terms of utility function. Moreover, we propose a simple dynamic pricing algorithm for the power substation to control the total demand of all customers to meet the target demand curve. Finally, simulations are shown to demonstrate the efficiency and effectiveness of the proposed game-theoretic algorithm.
We developed the Hong Kong Specific Learning Difficulties Behavior Checklist for Junior Secondary School Students (BCL-JS) for teachers to rate the frequency of 52 reading-related behavioral characteristics of Chinese secondary school students. An item factor analysis based on ratings on 947 students yielded seven distinct dimensions. In a separate sample of 90 students, the seven constructs of the BCL-JS significantly correlated with students’ performances on most literacy and reading-related cognitive measures, and differentiated adolescents with or without dyslexia. Discriminant analysis showed that the BCL-JS had a high rate of correct classification (82.2%). These findings support that the BCL-JS is a reliable screening tool for Chinese junior secondary school students at risk for dyslexia.
Atomistic lattice-gas models for thermodynamically and kinetically directed assembly are applied to Ru nanocluster formation on a monolayer of graphene supported on Ru(0001) at 309 K. Nanocluster density, mean size, height distribution, and spatial ordering are analyzed by kinetic Monte Carlo simulations. Both models can reproduce the experimental data, but additional density functional theory analysis favors the former.
The lifetime of contact binaries is an important parameter for studying the evolution of contact binaries. By reproducing the relative frequency of occurrence for contact binaries, we found that the lifetime of contact binaries decreases with increasing mass of the primaries. The lifetime of contact binaries is about 4%–10% of the main sequence lifetime of the primaries, and is about 0.006–0.65 Gyr. This suggests that the lifetime of contact binaries strongly depends on the mass of the primaries.