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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.
We identified and characterized a new cosmocercid nematode species, Cosmocercoides wuyiensis n. sp., through microscopic examination and sequencing of the partial small ribosomal RNA gene (18S rDNA), internal transcribed spacer (ITS) and mitochondrial cytochrome c oxidase subunit 1 (COI) genes. The new species was isolated from the intestine of the Asiatic frog Amolops wuyiensis Liu and Hu, 1975 captured from four localities of the Anhui province in south-east China. Among the 25 recorded species of the Cosmocercoides genus, the morphology of C. wuyiensis n. sp. is closest to that of C. kiliwai and C. malayensis, which were isolated from various Mexican frog and Malaysian lizard species, respectively. However, C. wuyiensis n. sp. displayed several distinguishing features, such as small size of the male body, two spicules of unequal lengths in the male, small gubernaculum, pre-, ad- and post-cloacal caudal rosette papillae in the ratio of 18–24:2:6 and simple papillae in the ratio of 14:multiple:4, circle and number of punctation in each rosette at 1:11–16, sharply conical tail-end and the presence of lateral alae and somatic papillae in both sexes. BLAST and the phylogenetic analyses of the 18S rDNA and ITS sequences indicated that C. wuyiensis n. sp. belonged to the genus Cosmocercoides, while that of the COI gene sequence of C. wuyiensis n. sp. showed 16.36% nucleotide divergence with C. pulcher and 47.99% nucleotide divergence with C. qingtianensis. The morphological and molecular characterization of C. wuyiensis n. sp. provides new taxonomic data for this genus.
Sodium and chloride are the key factors maintaining normal osmotic pressure (OSM) and volume of the extracellular fluid, and influencing the acid–base balance of body fluids. The experiment was conducted to investigate the effects of dietary Na+ and Cl− level on growth performance, excreta moisture, blood biochemical parameters, intestinal Na+–glucose transporter 1 (SGLT1) messenger RNA (mRNA), and Na+–H+ exchanger 2 (NHE2) mRNA, and to estimate the optimal dietary sodium and chlorine level for yellow-feathered chickens from 22 to 42days. A total of 900 22-day-old Lingnan yellow-feathered male chickens were randomly allotted to five treatments, each of which included six replicates of 30 chickens per floor pen. The basal control diet was based on corn and soybean meal (without added NaCl and NaHCO3). Treatments 2 to 5 consisted of the basal diet supplemented with equal weights of Na+ and Cl−, constituting 0.1%, 0.2%, 0.3% and 0.4% of the diets. Supplemental dietary Na+ and Cl− improved the growth performance (P<0.05). Average daily gain (ADG) showed a quadratic broken-line regression to increasing dietary Na+ and Cl− (R2=0.979, P<0.001), and reached a plateau at 0.1%. Supplemental Na+ and Cl− increased (P<0.05) serum Na+ and OSM in serum and showed a quadratic broken-line regression (R2=0.997, P=0.004) at 0.11%. However, supplemental Na+ and Cl− decreased (P<0.05) serum levels of K+, glucose (GLU) and triglyceride. Higher levels of Na+and Cl− decreased duodenal NHE2 transcripts (P<0.05), but had no effect on ileal SGLT1 transcripts. The activity of Na+ /K+-ATPase in the duodenum decreased (P<0.05) with higher levels of dietary Na+ and Cl−. In conclusion, the optimal dietary Na+ and Cl− requirements for yellow-feathered chickens in the grower phase, from 22 to 42 days of age, to optimize ADG, serum Na+, OSM, K+ and GLU were 0.10%, 0.11%, 0.11%,0.17% and 0.16%, respectively, by regression analysis.
The Pain Catastrophizing Scale (PCS) measures three aspects of catastrophic cognitions about pain—rumination, magnification, and helplessness. To facilitate assessment and clinical application, we aimed to (a) develop a short version on the basis of its factorial structure and the items’ correlations with key pain-related outcomes, and (b) identify the threshold on the short form indicative of risk for depression.
Social centers for older people.
664 Chinese older adults with chronic pain.
Besides the PCS, pain intensity, pain disability, and depressive symptoms were assessed.
For the full scale, confirmatory factor analysis showed that the hypothesized 3-factor model fit the data moderately well. On the basis of the factor loadings, two items were selected from each of the three dimensions. An additional item significantly associated with pain disability and depressive symptoms, over and above these six items, was identified through regression analyses. A short-PCS composed of seven items was formed, which correlated at r=0.97 with the full scale. Subsequently, receiver operating characteristic (ROC) curves were plotted against clinically significant depressive symptoms, defined as a score of ≥12 on a 10-item version of the Center for Epidemiologic Studies-Depression Scale. This analysis showed a score of ≥7 to be the optimal cutoff for the short-PCS, with sensitivity = 81.6% and specificity = 78.3% when predicting clinically significant depressive symptoms.
The short-PCS may be used in lieu of the full scale and as a brief screen to identify individuals with serious catastrophizing.
A new generation of high power laser facilities will provide laser pulses with extremely high powers of 10 petawatt (PW) and even 100 PW, capable of reaching intensities of
in the laser focus. These ultra-high intensities are nevertheless lower than the Schwinger intensity
at which the theory of quantum electrodynamics (QED) predicts that a large part of the energy of the laser photons will be transformed to hard Gamma-ray photons and even to matter, via electron–positron pair production. To enable the investigation of this physics at the intensities achievable with the next generation of high power laser facilities, an approach involving the interaction of two colliding PW laser pulses is being adopted. Theoretical simulations predict strong QED effects with colliding laser pulses of
focused to intensities
Various surgical approaches have been described to remove tumours in the parapharyngeal space. This study investigated the feasibility of a transoral approach in the surgical management of parapharyngeal space benign tumours located in the medial portion of the carotid sheaths and extending toward the skull base.
Thirty-two patients were selected and underwent a transoral or an endoscope-assisted transoral approach in the surgical management of parapharyngeal space benign tumours located in the medial portion of the carotid sheaths. Medical photographs were used.
All patients underwent complete resection of their lesions via a transoral or endoscope-assisted transoral approach. None of the patients demonstrated residual or recurrent neoplasms, either clinically or radiographically, during their follow up.
Based on our studies, we assert that transoral and endoscope-assisted transoral approaches are suitable in managing parapharyngeal space benign tumours located in the medial portion of the carotid sheaths and extending toward the skull base.
Hand-foot-mouth disease (HFMD) is an acute infectious disease caused by serotypes of the enterovirus (EV) family. HFMD reinfection occurs commonly in lack of cross-protection between different EV serotypes. In this study, we investigated the hazards of HFMD reinfection using Cox-proportional hazard model. Retrospective data of 95 209 HFMD cases in Wuhan during 2008–2015 was used. Kaplan–Meier survival methods and Cox-proportional hazard model were used to estimate the hazard probabilities. Of the all HFMD cases, about 2% experienced reinfection (1842/95 209). Kaplan–Meier curves revealed the reinfection risk sharply increased before 40 months from first infection. Higher hazards of reinfection were detected among those who were males, aged 3 years and below, scattered children, belonging to urban areas and first infected with coxsackievirus (CV)-A16 compared with their respective counterparts. Cox-proportional hazard model suggested that gender, age, group, living area and serotypes of first infection had significant effect on reinfection even after adjusting for potential confounding effects of other selected factors considered in the study. These results indicate that boys aged 3 years and below, especially those living in urban areas and first infected with CV-A16 are more prone to reinfection. Interventions should be imposed on these high-risk populations.
Influenza is a long-standing public health concern, but its transmission remains poorly understood. To have a better knowledge of influenza transmission, we carried out a detailed modelling investigation in a nosocomial influenza outbreak in Hong Kong. We identified three hypothesised transmission modes between index patient and other inpatients based on the long-range airborne and fomite routes. We considered three kinds of healthcare workers’ routine round pathways in 1140 scenarios with various values of important parameters. In each scenario, we used a multi-agent modelling framework to estimate the infection risk for each hypothesis and conducted least-squares fitting to evaluate the hypotheses by comparing the distribution of the infection risk with that of the attack rates. Amongst the hypotheses tested in the 1140 scenarios, the prediction of modes involving the long-range airborne route fit better with the attack rates, and that of the two-route transmission mode had the best fit, with the long-range airborne route contributing about 94% and the fomite route contributing 6% to the infections. Under the assumed conditions, the influenza virus was likely to have spread via a combined long-range airborne and fomite routes, with the former predominant and the latter negligible.
It is a challenge for small, fixed-wing aerial vehicles to maintain flight stability under gusts. Inspired by the geometric features and the structural dynamic characteristics of the gliding bird wing, an elastic wing with similar characteristics was designed and optimised for use as part of unmanned aerial vehicle. A flight dynamic model, which includes the coupling of the longitudinal flight modes and the aeroelastic modes of the flexible wing, was built to analyse the mechanisms of specific coupling for the structural characteristics of the wing design, and how these specific couplings affect flight dynamics. The results showed that the bio-inspired elastic wing effectively allows alleviation of the gust response of the prototype through coupling effects of the short period and the first aeroelastic mode, even with a considerable frequency gap. These effects become more significant when the airspeed becomes larger. The conclusions of this research can facilitate further development of bird-sized unmanned aerial vehicles to extend their applications and make these vehicles more adaptive for flight in complex atmospheric environments.
It was reported that high blood cholesterol levels increased the susceptibility to mitochondrial dysfunction. This study hypothesized that the gestational hypercholesterolemia (HC) could induce the mitochondrial dysfunction in term human placenta. The eligible pregnant women were recruited from Xuanwu Hospital in Beijing during their first prenatal visit (before their 10th week of pregnancy). In total, 19 pregnant women whose serum total cholesterol levels were higher than 7.25 mm at third trimester (measured at 36–38 weeks) were selected as gestational HC. Other 19 pregnant women with normal cholesterol level matched with age, pre-gestational body mass index, and the neonatal gender were included as the control group. Full-term placenta samples were collected. The mitochondrial DNA (mtDNA) copy number, messenger RNA (mRNA) expression of cytochrome c oxidase subunit I, adenosine triphosphate monophosphatase 6 (ATP6ase), citrate synthase, peroxisome proliferator-activated receptor-γ (PPARγ) co-activator 1α, PPARγ co-activator 1β and estrogen-related receptor-α, and the activity of mitochondrial respiratory chain enzyme complex were measured. Pregnancy outcomes were obtained by extraction from medical records and the labor ward register. The results showed that only placental mtDNA copy number and mRNA expression of ATP6ase were significantly decreased in HC group. No significant differences were detected of other measurements between the two groups. These findings indicated that gestational HC might not induce the damage of placental function seriously.
We are constructing a collector for capturing Interplanetary Dust Particles (IDPs) and space debris on space shuttle. The unit consists of three pieces of thin polyester film, equally spaced 7 cm apart, and an aerogel disk of 3 cm thickness. For each particle captured in the aerogel disk, we determine its direction of impact and its speed, from which we can trace its trajectory. The purpose of the experiment is to study the compositions of IDPs from different origins.
In ovo feeding (IOF) of l-arginine (Arg) can affect growth performance of broilers, but the response of IOF of Arg on breast muscle growth is unclear, and the mechanism involved in protein deposition remains unknown. Hense, this experiment was conducted to evaluate the effects of IOF of Arg on breast muscle growth and protein-deposited signalling in post-hatch broilers. A total of 720 fertile eggs were collected from 34-week-old Arbor Acres breeder hens and distributed to three treatments: (1) non-injected control group; (2) 7.5 g/l (w/v) NaCl diluent-injected control group; (3) 0.6 mg Arg/egg solution-injected group. At 17.5 days of incubation, fertile eggs were injected 0.6 ml solutions into the amnion of the injected groups. Upon hatching, 80 male chicks were randomly assigned to eight replicates of 10 birds each and fed ad libitum for 21 days. The results indicated that IOF of Arg increased relative breast muscle weight compared with those of control groups at hatch, 3-, 7- and 21-day post-hatch (P<0.05). In the Arg-injected group, the plasma total protein and albumen concentrations were higher at 7- and 21-day post-hatch than those of control groups (P<0.05). The alanine aminotransferase activity in Arg group was higher at hatch than that of control groups (P<0.05). The levels of triiodothyronine at four time points and thyroxine hormones at hatch, 7- and 21-day post-hatch in Arg group were higher than those of control groups (P<0.05). In addition, IOF of Arg increased the amino acid concentrations of breast muscle at hatch, 7- and 21-day post-hatch (P<0.05). In ovo feeding of Arg also enhanced mammalian target of rapamycin, ribosomal protein S6 kinase-1 and eIF4E-bindingprotein-1 messenger RNA expression levels at hatch compared with those of control groups (P<0.05). It was concluded that IOF of Arg treatment improved breast muscle growth, which might be associated with the enhancement of protein deposition.
Previous studies showed that butyrate played benefit roles in the health and metabolism of animals. However, little information on the effects of butyrate on the metabolism of piglets at the extraintestinal level is available. The present study investigated transcriptomic and metabolomic responses in the livers of pigs to evaluate the effects of intravenous sodium butyrate (SB) on the body’s metabolism at the extraintestinal level. A total of 12 Duroc×Landrace×Large White growing barrows (60 days of age) fitted with jugular vein cannula were randomly allocated to either the SB group or the control (CO) group. Pigs in the SB group were intravenously infused with 10 ml SB (200 mmol/l) for 7 days, whereas pigs in the CO group were treated with the same amount of saline. The livers of pigs were collected for gene expression and metabolome analyses. The RNA sequencing (RNA-Seq) analysis showed that the mRNA expression of Acyl-CoA synthetase long-chain family member 1 (ACSL1), carnitine palmitoyltransferase 1A (CPT1A), acetyl-CoA acyltransferase 2 (ACAA2) and phosphoenolpyruvate carboxykinase 1 (PCK1) were downregulated (Q<0.05), whereas fatty acid binding protein 1 (FABP1) and cytochrome P450 family 7 subfamily A member 1 (CYP7A1) were upregulated (P<0.05) by SB treatment, indicating a decrease in fatty acid oxidation and gluconeogenesis and an increase in fatty acid transportation and cholesterol metabolism. Gas chromatography-mass spectrometry analysis showed that raffinose was enriched in the SB group compared with the CO group, indicating a decrease in metabolism of galactose. Moreover, SB treatment significantly decreased the concentration of blood cholesterol. The results suggest that a short-term intravenous infusion of SB could modulate hepatic lipid metabolism by decreasing fatty acid oxidation and increasing fatty acid transportation and cholesterol metabolism.
Fermented soybean meal (FSM), which has lower anti-nutritional factors and higher active enzyme, probiotic and oligosaccharide contents than its unfermented form, has been reported to improve the feeding value of soybean meal, and hence, the growth performance of piglets. However, whether FSM can affect the bacterial and metabolites in the large intestine of piglets remains unknown. This study supplemented wet-FSM (WFSM) or dry-FSM (DFSM) (5% dry matter basis) in the diet of piglets and investigated its effects on carbon and nitrogen metabolism in the piglets’ large intestines. A total of 75 41-day-old Duroc×Landrace×Yorkshire piglets with an initial BW of 13.14±0.22 kg were used in a 4-week feeding trial. Our results showed that the average daily gain of piglets in the WFSM and DFSM groups increased by 27.08% and 14.58% and that the feed conversion ratio improved by 18.18% and 7.27%, respectively, compared with the control group. Data from the prediction gene function of Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) based on 16S ribosomal RNA (rRNA) sequencing showed that carbohydrate metabolism function families in the WFSM and DFSM groups increased by 3.46% and 2.68% and that the amino acid metabolism function families decreased by 1.74% and 0.82%, respectively, compared with the control group. These results were consistent with those of other metabolism studies, which showed that dietary supplementation with WFSM and DFSM increased the level of carbohydrate-related metabolites (e.g. 4-aminobutanoate, 5-aminopentanoate, lactic acid, mannitol, threitol and β-alanine) and decreased the levels of those related to protein catabolism (e.g. 1,3-diaminopropane, creatine, glycine and inosine). In conclusion, supplementation with the two forms of FSM improved growth performance, increased metabolites of carbohydrate and reduced metabolites of protein in the large intestine of piglets, and WFSM exhibited a stronger effect than DFSM.
To investigate the effectiveness and usability of automated procedural guidance during virtual temporal bone surgery.
Two randomised controlled trials were performed to evaluate the effectiveness, for medical students, of two presentation modalities of automated real-time procedural guidance in virtual reality simulation: full and step-by-step visual presentation of drillable areas. Presentation modality effectiveness was determined through a comparison of participants’ dissection quality, evaluated by a blinded otologist, using a validated assessment scale.
While the provision of automated guidance on procedure improved performance (full presentation, p = 0.03; step-by-step presentation, p < 0.001), usage of the two different presentation modalities was vastly different (full presentation, 3.73 per cent; step-by-step presentation, 60.40 per cent).
Automated procedural guidance in virtual temporal bone surgery is effective in improving trainee performance. Step-by-step presentation of procedural guidance was engaging, and therefore more likely to be used by the participants.
The human retina is supplied by two vascular systems: the highly vascular choroidal, situated behind the retina; and the retinal, which is dependent on the restriction that the light path must be minimally disrupted. Between these two circulations, the avascular retinal layers depend on diffusion of metabolites through the tissue. Oxygen supply to these layers may be threatened by diseases affecting microvasculature, for example diabetes and hypertension, which may ultimately cause loss of sight.
An accurate model of retinal blood flow will therefore facilitate the study of retinal oxygen supply and, hence, the complications caused by systemic vascular disease. Here, two simple models of the blood flow and exchange of hydrogen with the retina are presented and compared qualitatively with data obtained from experimental measurements. The models capture some interesting features of the exchange and highlight effects that will need to be considered in a more sophisticated model and in the interpretation of experimental results.