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Ovarian follicle selection is a natural biological process in the pre-ovulatory hierarchy in birds that drives growing follicles to be selected within the ovulatory cycle. Follicle selection in birds is strictly regulated, involving signaling pathways mediated by dietary nutrients, gonadotrophic hormones and paracrine factors. This study aimed to test the hypothesis that dietary Ca may participate in regulating follicle selection in laying ducks through activating the signaling pathway of cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA)/extracellular signal-regulated kinase (ERK), possibly mediated by gonadotrophic hormones. Female ducks at 22 weeks of age were initially fed one of two Ca-deficient diets (containing 1.8% or 0.38% Ca) or a Ca-adequate control diet (containing 3.6% Ca) for 67 days (depletion period), then all birds were fed the Ca-adequate diet for an additional 67 days (repletion period). Compared with the Ca-adequate control, ducks fed 0.38% Ca during the depletion period had significantly decreased (P < 0.05) numbers of hierarchical follicles and total ovarian weight, which were accompanied by reduced egg production. Plasma concentration of FSH was decreased by the diet containing 1.8% Ca but not by that containing 0.38%. The ovarian content of cAMP was increased with the two Ca-deficient diets, and phosphorylation of PKA and ERK1/2 was increased with 0.38% dietary Ca. Transcripts of ovarian estradiol receptor 2 and luteinizing hormone receptor (LHR) were reduced in the ducks fed the two Ca-deficient diets (P < 0.05), while those of the ovarian follicle stimulating hormone receptor (FSHR) were decreased in the ducks fed 0.38% Ca. The transcript abundance of ovary gap junction proteins, A1 and A4, was reduced with the Ca-deficient diets (P < 0.05). The down-regulation of gene expression of gap junction proteins and hormone receptors, the increased cAMP content and the suppressed hierarchical follicle numbers were reversed by repletion of dietary Ca. These results indicate that dietary Ca deficiency negatively affects follicle selection of laying ducks, independent of FSH, but probably by activating cAMP/PKA/ERK1/2 signaling pathway.
The risk factors of criminal behavior in patients with schizophrenia are not well explored. This study is to explore the risk factors for criminal behavior in patients with schizophrenia in rural China.
We used data from a 14-year prospective follow-up study (1994-2008) of criminal behavior among a cohort (n=510) of patients with schizophrenia in Xinjin County, Chengdu, China.
There were 489 patients (95.9%) who were followed up from 1994 to 2008. The rate of criminal behavior was 13.5% among these patients with schizophrenia during the follow-up period. Compared with female subjects (6 cases, 20.0%), male patients had significantly higher rate of violent criminal behavior (e.g., arson, sexual assault, physical assault, and murder) (24 cases, 80.0%) (p< 0.001). Bivariate analyses showed that the risk of criminal behavior was significantly associated with being unmarried, of younger age, previous violent behavior, homelessness, lower family economic status, no family caregivers, and higher scores on measures (PANSS) of positive, negative, and total symptoms of illness. In multiple logistic regression analyses being unmarried and previous violent behavior were identified as independent predictors of increased criminal behavior in persons with schizophrenia.
The risk factors for criminal behavior among patients with schizophrenia should be understood within a particular social context. Criminal behavior may be predicted by specific characteristics of patients with schizophrenia in rural community. The findings of risk factors for criminal behavior should be considered in planning community mental health care and interventions for high-risk patients and their families.
There seems to be geographical differences in decisions about breast conserving surgery (BCS) in breast cancer patients. This study was to evaluate patients’ attitude to BCS and to assess the factors affecting cancer practice in West China.
A structured questionnaire was distributed to 184 patients, eliciting information about the patients’ characteristics, occupation, education, family life, recognition of illness, knowledge about BCS, the main means of gaining surgery information, selecting surgery approaches, preferences to breast reservation.
In all, 163 patients completed the questionnaire. The results indicated that only 7.4% of patients received BCS and 23% of the remaining patients desired to have BCS and the affecting factors were significantly associated with their family life, recognition of illness and the main means of gaining surgery information (P < 0.05). No associations were between BCS selecting and the other variables studied. The most frequent reasons for selecting BCS were keeping the female shape and improving quality of life (71%), the second most were postoperative recovery, minimal influence of physical function (47%) and patients’ knowledge about BCS (42%). The most frequent reasons for not selecting BCS were uncertainty about BCS results and worry about recurrence (81%), the second most was the elderly age unnecessary for BCS (40%).
The findings indicate that breast cancer patients in West China do not take BCS as the first choice as the best treatment method. It is warranted that further study of more patients, attitude of patients’ partners and physicians to BCS.
To get a more robust DNA methylation profile from the data given by a published article of a MZ study of psychiatry.
Considering the relevance of birth weight with DNA methylation profiles, we reanalyzed the data from the paper of Mill etc. (DOI: 10.1002/ajmg.b.30316) with rearrangement of the group order within twin pair, prior if lighter in birth weight. Statistical methods used are including mean, correlation and paired-samples t-test (considering twins’ particularity).
We calculated twin difference by lighter twin's methylation percentage minus that of heavier twin. The mean of CpG1 methylation differences is -7.08% while -7.17% for CpG2. The two means have no statistical significant difference in a paired-samples t-test (t=0.027, p=0.979, 2-tailed). These results are different from the original paper: 10.3% for CpG1 and 16.1% for CpG2, which are statistical significantly different (t=-2.792, p=0.018, 2-tailed). Besides, we found that in the lighter twin group, the methylation percentage are statistical significantly different between CpG1 and CpG2 (t=2.627, p=0.024, 2-tailed). As to correlation analysis, we got a slightly different result: correlation between MZ differences in two sites is weaker after rearrangement (r=0.875, while r=0.913 before arrangement, both p< 0.001).
According to our study, the results imply that twin differences may not be the only thing worthy of investigation. Different patterns among CpGs in certain kinds of subgroups should also need attention. We need conduct a robust data analysis strategy in our researches on the epigenetic aspects of psychiatry, where monozygotic twins have a favorable utility.
Many family characteristics were reported to increase the risk of bipolar disorder (BPD). The development of BPD may be mediated through different pathways, involving diverse risk factor profiles. We evaluated the associations of family characteristics to build influential causal-pie models to estimate their contributions on the risk of developing BPD at the population level. We recruited 329 clinically diagnosed BPD patients and 202 healthy controls to collect information in parental psychopathology, parent-child relationship, and conflict within family. Other than logistic regression models, we applied causal-pie models to identify pathways involved with different family factors for BPD. The risk of BPD was significantly increased with parental depression, neurosis, anxiety, paternal substance use problems, and poor relationship with parents. Having a depressed mother further predicted early onset of BPD. Additionally, a greater risk for BPD was observed with higher numbers of paternal/maternal psychopathologies. Three significant risk profiles were identified for BPD, including paternal substance use problems (73.0%), maternal depression (17.6%), and through poor relationship with parents and conflict within the family (6.3%). Our findings demonstrate that different aspects of family characteristics elicit negative impacts on bipolar illness, which can be utilized to target specific factors to design and employ efficient intervention programs.
Patients with chronic kidney disease (CKD) have more cognitive impairments. However, the etiologies are not fully clear. Plasma homocysteine levels and vascular burden rise in CKD; meanwhile, high homocysteine levels and vascular factors are known risk factors of dementia in non-CKD patients. Thus, we aimed to investigate the association between homocysteine, vascular burden and cognitive impairment in CKD and to see if the effect of elevated homocysteine on cognitive impairment mediated by vascular factor.
146 patients with CKD and 69 normal comparisons were recruited. Cognitive function was evaluated by comprehensive neuropsychological tests assessing processing speed, executive function, language, visuospatial function, memory, and attention domains. Vascular burden was assessed by Framinghan cardiovascular risk scale (FCRS) which indicates risk of atherosclerotic diseases including stroke.
In controlled analysis, patients with CKD had lower scores in all cognitive domains, and had higher homocysteine levels (18.5±6.4 vs. 9.8±2.9, p< 0.0001) and FCRS(17.0±4.7 vs. 14.0±4.7, p< 0.0001). Among patients with CKD, higher homocysteine levels (p=0.026) were associated with lower score on digit symbol task which is related to processing speed and executive function with controlling for age, sex, education and stage of CKD. The association persisted (p=0.047) after controlling for vascular risks.
Patients with CKD had extensive cognitive impairments. Elevated homocysteine levels may be an risk factor, which is independent of vascular burden, of cognitive impairment on processing speed and executive function. Further studies to investigate if normalization of homocysteine can improve cognitive function will be suggested.
Previously, we reported the clinical efficacy of MPH-LA in adult ADHD evaluated in a 40-week, randomised, double-blind, placebo-controlled, multicentre core study [comprising of dose confirmation (9-week), real-life dose optimisation (5-week) and maintenance of effect phases (6- month)] (Atten Defic Hyperact Disord. 2013;(5):219–220). Here, we report the long-term efficacy from the 26-week extension phase of the same study.
During the extension phase, patients initiated treatment with MPH-LA 20 mg/day (oral, once daily capsules); uptitrated to optimal dose of 40, 60 or 80 mg/day in increments of 20 mg/week. Change in DSM-IV ADHD rating scale (RS) and SDS total scores at the end of study, were evaluated from the baseline of maintenance of effect phase of the core study and the baseline of extension phase.
At the end of the extension phase, the mean change in DSM-IV ADHD RS and SDS total scores from baseline of the maintenance of effect phase was −0.9 and −1.4 points respectively; and from baseline of extension phase was −7.2 and −4.8 respectively (Table). No new or unexpected safety concerns were observed during the extension phase.
MPH-LA continued to maintain clinical efficacy in adult ADHD patients over long-term.
Table DSM-IV ADHD RS, SDS total scores and change from baseline at the end of extension phase
Previous studies have shown that the polymorphisms in COMT gene and environmental factors affect the risk of drug dependence, but there’s no research shown in relapse of heroin dependence, and the mechanism underlying remains uncertain.
Examine the interaction between allelic variants of the catechol-O- methlytransferase (COMT) gene and environmental factors (encountering drug-related environmental situations, social support) in contribution to relapse in heroin dependence.
Construct the gene-environment interaction model in order to understand the mechanism for relapse in heroin dependence.
The 249 heroin dependent subjects who followed up at one year after abstinent by using the natural history interview (NHI), social support rateing Scale (SSRS), and other questionnaires were genotyped for eight tagging single nucleotide polymorphisms (SNP) on the COMT gene. General Multifactor Dimensionality Reduction (GMDR) was used to construct the gene-environment interaction model which impacting relapse in heroin dependence.
The relapse group had higher frequencies of encountering drug-related environment (EDE) and G allele and GG genotype frequencies on COMT gene rs4680 locus and less Social Support Scale scores than that in the abstinence group. Logistic regression analysis showed that encountering more drug-related environment and GG genotype carriers were the risk factors for relapse in heroin dependence. GMDR analysis showed that the COMT gene was interact with the frequency of EDE and social support level to impact the relapse in heroin dependence.
Gene-environment interaction between COMT gene and the frequency of EDE and social support were related to heroin dependence relapse.
Recent epidemiology studies have reported the prevalence of adult ADHD to be approximately 4%, however approved treatments are limited.
Primary objectives were to confirm the clinically-effective and safe dosage range of MPH-LA in adults with ADHD and evaluate the 6-month maintenance of effect.
Treatment Period (TP) 1: Patients were randomized to double-blind placebo, MPH-LA 40, 60, or 80 mg/day for 9- weeks (3-week titration, 6-week fixed-dose) to evaluate change in DSM-IV ADHD-RS and Sheehan Disability Scale (SDS) total score in TP1. TP2: 5-week titration to individual optimal dose. TP3: Patients were randomized to their optimal dose or placebo for 6-months double-blind withdrawal period to evaluate percentage of treatment failures during TP3.
Improvement from baseline in total score on the DSM-IV ADHD-RS and SDS was significantly greater than placebo for all MPH-LA dose levels (table). Patients treated with MPH-LA had significantly lower treatment failure rates (21.34%) compared to placebo in TP3 (49.6%; odds-ratio (95%CI=0.3 (0.2, 0.4); p< 0.0001). The safety results were consistent with the established safety profile for MPH-LA.
[Improvement by week 9: DSM-IV ADHD-RS and SDS].
N=Full Analysis Set for TP1 (All randomized patients receiving one dose of study drug in TP1)
MPH-LA administered at 40-80mg/day demonstrated superior ADHD symptom control and reduction in functional impairment compared to placebo and demonstrated maintenance of effect over 6 months. No unexpected adverse events were observed.
Metabolic abnormality is common among schizophrenia patients. Some metabolic traits were found associated with subgroups of schizophrenia patients.
We examined a possible relationship between metabolic abnormality and psychosis profile in schizophrenia patients.
Three hundred and seventy-two chronic schizophrenia patients treated with antipsychotics for more than 2 years were assessed with the Positive and Negative Syndrome Scale. A set of metabolic traits was measured at scheduled checkpoints between October 2004 and September 2006.
Multiple regressions adjusted for sex showed negative correlations between body mass index (BMI) and total score and all subscales; triglycerides (TG) was negatively correlated with total score and negative syndrome, while HDLC was positively correlated with negative syndrome. When sex interaction was concerned, total score was negatively correlated with BMI but not with others; negative syndrome was negatively correlated with BMI and positively with HDLC. No metabolic traits were correlated with positive syndrome or general psychopathology.
Loss of body weight is a serious health problem in schizophrenia patients with severe psychosis syndrome, especially the negative syndrome. Schizophrenia patients with severe negative syndrome may have a distinct lipid pathophysiology in comparison with those who were less severe in the domain.
Alcohol is legally accessible and widely used in Taiwan, but few studies have addressed alcohol-drinking problems in hospital settings.
To explore (1) the prevalence and risk factors for hazardous alcohol-drinking problems and (2) previous assessments and interventions for alcohol-drinking problems among a general Chinese patient population.
Self-report data were collected from 484 patients at five randomly selected hospitals.
The prevalence of hazardous alcohol-drinking problems was 19.2%. Logistic regression analysis revealed that risk factors for hazardous drinking problems were being male, smoking, and chewing betel quid. Only 29.1% of participants were assessed for drinking problems in the past year. Only 38.7% of participants with drinking problems had received a drinking intervention in the past year.
Alcohol problems in Taiwanese general hospitals are insufficiently assessed and targeted with interventions. Targeting high-risk groups and integrating psychiatric healthcare teams in general hospitals are important to prevent patients’ drinking problems.
The safety profile of MPH-LA in the paediatric population has been well studied. However, there are very limited studies reporting safety of MPH-LA in adults. We present the safety profile of MPH-LA in adults and from a pooled analysis in children.
Data from 3 multiple-dose, double-blind, placebo-controlled studies of 7-12 weeks duration in children with ADHD; MPH-LA (10-80mg/d) (n=314) & placebo (n=318) (aged 6-12 yrs in 2 studies &13-17 yrs in one study) were pooled for this analysis. In addition, data from 722 adult patients, 18-60 yrs of age with ADHD receiving MPH-LA 40-80 mg/d (n=542) or placebo (n=180) from double-blind dose confirmation phase of 9-week duration from one study was included in the analysis.
Common adverse events (AEs) reported by both adult and paediatric ADHD patients were decreased appetite, headache, nasopharyngitis, nausea, and insomnia (Table). Incidence of serious AEs (SAEs) was low with MPH-LA in both adults (0.7%) and children (0.6%) compared with placebo group (1.1% in adults and 0.3% in children).
Our findings show that safety profile of MPH-LA in adults is similar to that observed in the paediatric population.
Adverse events (>5%) by preferred term in multiple dose, placebo-controlled studies In adult and paedlatrlc ADHD patients
Most common AEs
MPH-LA N=542, n (%)
Placebo N=1B0, n (%)
MPH-LA N=314, n (%)
Placebo N=31S, n (%)
Total number of patients with anyAE
Analysis data set: Safety population of double-blind dose confirmation phase of 9-week duration conducted in adult ADHD patients and pooled safety population from 3 paediatric studies.
Chlamydia trachomatis (CT) infection has been a major public health threat globally. Monitoring and prediction of CT epidemic status and trends are important for programme planning, allocating resources and assessing impact; however, such activities are limited in China. In this study, we aimed to apply a seasonal autoregressive integrated moving average (SARIMA) model to predict the incidence of CT infection in Shenzhen city, China. The monthly incidence of CT between January 2008 and June 2019 in Shenzhen was used to fit and validate the SARIMA model. A seasonal fluctuation and a slightly increasing pattern of a long-term trend were revealed in the time series of CT incidence. The monthly CT incidence ranged from 4.80/100 000 to 21.56/100 000. The mean absolute percentage error value of the optimal model was 8.08%. The SARIMA model could be applied to effectively predict the short-term CT incidence in Shenzhen and provide support for the development of interventions for disease control and prevention.
To describe the infection control preparedness measures undertaken for coronavirus disease (COVID-19) due to SARS-CoV-2 (previously known as 2019 novel coronavirus) in the first 42 days after announcement of a cluster of pneumonia in China, on December 31, 2019 (day 1) in Hong Kong.
A bundled approach of active and enhanced laboratory surveillance, early airborne infection isolation, rapid molecular diagnostic testing, and contact tracing for healthcare workers (HCWs) with unprotected exposure in the hospitals was implemented. Epidemiological characteristics of confirmed cases, environmental samples, and air samples were collected and analyzed.
From day 1 to day 42, 42 of 1,275 patients (3.3%) fulfilling active (n = 29) and enhanced laboratory surveillance (n = 13) were confirmed to have the SARS-CoV-2 infection. The number of locally acquired case significantly increased from 1 of 13 confirmed cases (7.7%, day 22 to day 32) to 27 of 29 confirmed cases (93.1%, day 33 to day 42; P < .001). Among them, 28 patients (66.6%) came from 8 family clusters. Of 413 HCWs caring for these confirmed cases, 11 (2.7%) had unprotected exposure requiring quarantine for 14 days. None of these was infected, and nosocomial transmission of SARS-CoV-2 was not observed. Environmental surveillance was performed in the room of a patient with viral load of 3.3 × 106 copies/mL (pooled nasopharyngeal and throat swabs) and 5.9 × 106 copies/mL (saliva), respectively. SARS-CoV-2 was identified in 1 of 13 environmental samples (7.7%) but not in 8 air samples collected at a distance of 10 cm from the patient’s chin with or without wearing a surgical mask.
Appropriate hospital infection control measures was able to prevent nosocomial transmission of SARS-CoV-2.
The foetal programming hypothesis posits that optimising early life factors e.g. maternal diets can help avert the burden of adverse childhood outcomes e.g. childhood obesity. To improve applicability to public health messaging, we investigated whether maternal whole diet quality and inflammatory potential influence childhood adiposity in a large consortium.
We harmonized and pooled individual participant data from up to 8,769 mother-child pairs in 7 European mother-offspring cohorts. Maternal early-, late-, and whole-pregnancy dietary quality and inflammatory potential were assessed with Dietary Approaches to Stop Hypertension (DASH) and energy-adjusted Dietary Inflammatory Index (E-DII), respectively. Primary outcome was childhood overweight and obesity (OWOB), defined as age- and sex-specific body-mass-index-z score (BMIz) > 85th percentile based on WHO growth standard. Secondary outcomes were sum-of-skinfold-thickness (SST), fat-mass-index (FMI) and fat-free-mass-index (FFMI) in available cohorts. Outcomes were assessed in early- [mean (SD) age: 2.8 (0.3) y], mid- [6.2 (0.6) y], and late-childhood [10.6 (1.2) y]. We used multivariable regression analyses to assess the associations of maternal E-DII and DASH with offspring adiposity outcomes in cohort-specific analyses, with subsequent random-effects meta-analyses. Analyses were adjusted for maternal age, pre-pregnancy BMI, parity, lifestyle factors, energy intake, educational attainment, offspring age and sex.
A more pro-inflammatory maternal diet, indicated by higher E-DII, was associated with a higher risk of offspring late-childhood OWOB [pooled-OR (95% CI) comparing highest vs. lowest E-DII quartiles: 1.22 (1.01,1.47) for whole-pregnancy and 1.38 (1.05,1.83) for early-pregnancy; both P < 0.05]. Moreover, higher late-pregnancy E-DII was associated with higher mid-childhood FMI [pooled-β (95% CI): 0.11 (0.003,0.22) kg/m2; P < 0.05]; trending association was observed for whole-pregnancy E-DII [0.12 (-0.01,0.25) kg/m2; P = 0.07]. A higher maternal dietary quality, indicated by higher DASH score, showed a trending inverse association with late-childhood OWOB (pooled-OR (95% CI) comparing highest vs. lowest DASH quartiles: 0.58 (0.32,1.02; P = 0.06). Higher early-pregnancy DASH was associated with lower late-childhood SST [pooled-β (95% CI): -1.9 (-3.6,-0.1) cm; P < 0.05] and tended to be associated with lower late-childhood FMI [-0.34 (-0.71,0.04) kg/m2; P = 0.08]. Higher whole-pregnancy DASH tended to associate with lower early-childhood SST [-0.33 (-0.72,0.06) cm; P = 0.10]. Results were similar when modelling DASH and E-DII continuously.
Analysis of pooled data suggests that pro-inflammatory, low-quality maternal antenatal diets may influence offspring body composition and obesity risk, especially during mid- or late-childhood. Due to variation of data availability at each timepoint, our results should be interpreted with caution. Because most associations were observed at mid-childhood or later, future studies will benefit from a longer follow-up.
The influence of combined corrosion and vibration to the anti-loosening performance of a precision locknut used in a machine tool is investigated. Firstly, the locknut was submerged in 5% NaCl solution according to ASTM B895 standard for corrosion testing. The locknuts, after submerged in 1-hr, 2-hr and 4-hr periods, respectively, were then installed on the rotating spindle in a vertical dynamic impact tester for performing anti-loosening test. The initial installed pretension was 9800 N and the spindle was rotating in a constant speed of 1000 rpm. Turmogrease Li 802 EP lubricant was used on the contact surface between spindle thread and locknut. The set screws on the locknut were tightened sequentially and evenly in three-stage of torque: 1.96 N-m, 3.92 N-m and 5.88 N-m. Its real-time pretension variation with the periodic transverse impact and its final loosening torque were measured. Accordingly, the axial force ratio and anti-loosening torque ratio were calculated and discussed. It was found that corrosion treatment had similar influence on both the axial force ratio and the anti-loosening torque ratio. More corrosion on the locknut with longer submersion in NaCl solution deteriorated its anti-loosening characteristics. The result could serve as the reference for evaluating the fastening performance of precision locknut and guide the design and manufacturing for the application improvement.
Although numerous studies have investigated the individual effects of salinity, irrigation and fertilization on soil microbial communities, relatively less attention has been paid to their combined influences, especially using molecular techniques. Based on the field of orthogonal designed test and deoxyribonucleic acid sequencing technology, the effects of saline water irrigation amount, salinity level of irrigation water and nitrogen (N) fertilizer rate on soil bacterial community structure were investigated. The results showed that the irrigation amount was the most dominant factor in determining the bacterial richness and diversity, followed by the irrigation water salinity and N fertilizer rate. The values of Chao1 estimator, abundance-based coverage estimator and Shannon indices decreased with an increase in irrigation amount while increased and then decreased with an increase in irrigation water salinity and N fertilizer rate. The highest soil bacterial richness and diversity were obtained under the least irrigation amount (25 mm), medium irrigation water salinity (4.75 dS/m) and medium N fertilizer rate (350 kg/ha). However, different bacterial phyla were found to respond distinctively to these three factors: irrigation amount significantly affected the relative abundances of Proteobacteria and Chloroflexi; irrigation water salinity mostly affected the members of Actinobacteria, Gemmatimonadetes and Acidobacteria; and N fertilizer rate mainly influenced the Bacteroidetes' abundance. The results presented here revealed that the assessment of soil microbial processes under combined irrigation and fertilization treatments needed to be more careful as more variable consequences would be established by comparing with the influences based on an individual factor, such as irrigation amount or N fertilizer rate.
In this study, the thermal deformation of a machine tool structure due to the heat generated during operation was analyzed, and embedded cooling channels were applied to exchange the heat generated during the operation to achieve thermal error suppression. Then, the finite volume method was used to simulate the effect of cooling oil temperature on thermal deformation, and the effect of thermal suppression was experimentally studied using a feed system combined with a cooler to improve the positioning accuracy of the machine tool. In this study, the supply oil temperature in the structural cooling channels was found to significantly affect the position accuracy of the moving table and moving carrier. If the supply oil temperature in the cooling channels is consistent with the operational ambient temperature, the position accuracy of the moving table in the Y direction and the moving carrier in the X and Z directions has the best performance under different feed rates. From the thermal suppression experiments of the embedded cooling channels, the positioning accuracy of the feed system can be improved by approximately 25.5 % during the dynamic feeding process. Furthermore, when the hydrostatic guideway is cooled and dynamic feeding is conducted, positioning accuracy can be improved by up to 47.8 %. The machining accuracy can be improved by approximately 60 % on average by using the embedded cooling channels in this study. Therefore, thermal suppression by the cooling channels in this study can not only effectively improve the positioning accuracy but also enhance machining accuracy, proving that the method is effective for enhancing machine tool accuracy.
Abnormal effort-based decision-making represents a potential mechanism underlying motivational deficits (amotivation) in psychotic disorders. Previous research identified effort allocation impairment in chronic schizophrenia and focused mostly on physical effort modality. No study has investigated cognitive effort allocation in first-episode psychosis (FEP).
Cognitive effort allocation was examined in 40 FEP patients and 44 demographically-matched healthy controls, using Cognitive Effort-Discounting (COGED) paradigm which quantified participants’ willingness to expend cognitive effort in terms of explicit, continuous discounting of monetary rewards based on parametrically-varied cognitive demands (levels N of N-back task). Relationship between reward-discounting and amotivation was investigated. Group differences in reward-magnitude and effort-cost sensitivity, and differential associations of these sensitivity indices with amotivation were explored.
Patients displayed significantly greater reward-discounting than controls. In particular, such discounting was most pronounced in patients with high levels of amotivation even when N-back performance and reward base amount were taken into consideration. Moreover, patients exhibited reduced reward-benefit sensitivity and effort-cost sensitivity relative to controls, and that decreased sensitivity to reward-benefit but not effort-cost was correlated with diminished motivation. Reward-discounting and sensitivity indices were generally unrelated to other symptom dimensions, antipsychotic dose and cognitive deficits.
This study provides the first evidence of cognitive effort-based decision-making impairment in FEP, and indicates that decreased effort expenditure is associated with amotivation. Our findings further suggest that abnormal effort allocation and amotivation might primarily be related to blunted reward valuation. Prospective research is required to clarify the utility of effort-based measures in predicting amotivation and functional outcome in FEP.
There is evidence indicating that using the current UK energy feeding system to ration the present sheep flocks may underestimate their nutrient requirements. The objective of the present study was to address this issue by developing updated maintenance energy requirements for the current sheep flocks and evaluating if these requirements were influenced by a range of dietary and animal factors. Data (n = 131) used were collated from five experiments with sheep (5 to 18 months old and 29.0 to 69.8 kg BW) undertaken at the Agri-Food and Biosciences Institute of the UK from 2013 to 2017. The trials were designed to evaluate the effects of dietary type, genotype, physiological stage and sex on nutrient utilization and energetic efficiencies. Energy intake and output data were measured in individual calorimeter chambers. Energy balance (Eg) was calculated as the difference between gross energy intake and a sum of fecal energy, urine energy, methane energy and heat production. Data were analysed using the restricted maximum likelihood analysis to develop the linear relationship between Eg or heat production and metabolizable energy (ME) intake, with the effects of a range of dietary and animal factors removed. The net energy (NEm) and ME (MEm) requirements for maintenance derived from the linear relationship between Eg and ME intake were 0.358 and 0.486 MJ/kg BW0.75, respectively, which are 40% to 53% higher than those recommended in energy feeding systems currently used to ration sheep in the USA and the UK. Further analysis of the current dataset revealed that concentrate supplement, sire type or physiological stage had no significant effect on the derived NEm values. However, female lambs had a significantly higher NEm (0.352 v. 0.306 or 0.288 MJ/kg BW0.75) or MEm (0.507 v. 0.441 or 0.415 MJ/kg BW0.75) than those for male or castrated lambs. The present results indicate that using present energy feeding systems in the UK developed over 40 years ago to ration the current sheep flocks could underestimate maintenance energy requirements. There is an urgent need to update these systems to reflect the higher metabolic rates of the current sheep flocks.