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The effects of macronutrient intake on obesity are controversial. This research aims to investigate the associations between macronutrient intake and new-onset overweight/obesity. The relationship between the consumption of carbohydrate and total fat and obesity was assessed by the multivariable Cox model in this 11-year cohort, which included 6612 adults (3291 men and 3321 women) who were free of overweight and obesity at baseline. The dietary intake was recorded using a 24-h recall method for three consecutive days. Moreover, substitution models were developed to distinguish the effects of macronutrient composition alteration from energy intake modification. During 7·5 person years (interquartile range 4·3, 10·8) of follow-up, 1807 participants became overweight or obese. After adjusting for risk factors, the hazard ratio (HR) of overweight/obesity in extreme quintiles of fat was 1·48 (quintile 5 v. quintile 1, 95 % CI 1·16, 1·89; Ptrend = 0·02) in women. Additionally, replacing 5 % of energy from carbohydrate with equivalent energy from fat was associated with an estimated 4·3 % (HR 1·043, 95 % CI 1·007, 1·081) increase in overweight/obesity in women. Moreover, dietary carbohydrate was inversely associated with overweight/obesity (quintile 5 v. quintile 1, HR 0·70, 95 % CI 0·55, 0·89; Ptrend = 0·02) in women. Total fat was related to a higher risk of overweight/obesity, whereas high carbohydrate intake was related to a lower risk of overweight/obesity in women, which was not observed in men.
The aim of this network meta-analysis is to compare bone mineral density (BMD) changes among different osteoporosis prevention interventions in postmenopausal women. We searched MEDLINE, Embase and Cochrane Library from inception to 24 February 2019. Included studies were randomised controlled trials (RCT) comparing the effects of different treatments on BMD in postmenopausal women. Studies were independently screened by six authors in three pairs. Data were extracted independently by two authors and synthesised using Bayesian random-effects network meta-analysis. The results were summarised as mean difference in BMD and surface under the cumulative ranking (SUCRA) of different interventions. A total of ninety RCT (10 777 participants) were included. Ca, vitamin D, vitamin K, oestrogen, exercise, Ca + vitamin D, vitamin D + vitamin K and vitamin D + oestrogen were associated with significantly beneficial effects relative to no treatment or placebo for lumbar spine (LS). For femoral neck (FN), Ca, exercise and vitamin D + oestrogen were associated with significantly beneficial intervention effects relative to no treatment. Ranking probabilities indicated that oestrogen + vitamin D is the best strategy in LS, with a SUCRA of 97·29 % (mean difference: +0·072 g/cm2 compared with no treatment, 95 % credible interval (CrI) 0·045, 0·100 g/cm2), and Ca + exercise is the best strategy in FN, with a SUCRA of 79·71 % (mean difference: +0·029 g/cm2 compared with placebo, 95 % CrI –0·00093, 0·060 g/cm2). In conclusion, in postmenopausal women, many interventions are valuable for improving BMD in LS and FN. Different intervention combinations can affect BMD at different sites diversely.
Porphyrins are a class of conjugated molecules that structurally and functionally resemble natural photosynthetic and enzymatic chromophores. Crystalline solids self-assembled from anionic and cationic porphyrins yield a new class of multifunctional optoelectronic micro- and nanomaterials. In this article, we provide details on the concept of binary ionic self-assembly (ISA) and ionized forms of porphyrins, as well as formation of hierarchical structures, including nanotubes, rods and ribbons, sheets, and three-dimensional clover-like shapes, spheres, and sheaf-like structures. We summarize key physical properties from ultraviolet–visible characterizations of J-aggregate, exciton delocalization and extended π–π stacking, and related electronic and light-harvesting properties of the structures. Depending on the molecular subunits, the functionalities of the ISA materials are altered. These ISA nanostructures possess attractive light-harvesting and charge- and energy-transport functionalities and allow access to a novel class of nanomaterials with potential for applications in sensors, photovoltaics, photocatalysis, and solar power.
Cerebrovascular disease is the most common cause of death in China, and the incidence of ischemic stroke (240 per 100,000 people) is higher than that of hemorrhagic stroke (82 per 100,000 people). More than 80 percent of strokes can be prevented by early control of risk factors. Therefore, identifying and managing high-risk groups is a top priority in preventing stroke. The CHA2DS2-VASc score is a key prediction tool for stratifying stroke risk in individuals with atrial fibrillation (AF) as follows: zero score is low risk; one is intermediate risk; and two is high risk. The present study was undertaken to evaluate the accuracy of the CHA2DS2-VASc scoring system for stratifying ischemic stroke risk in the non-AF population.
We searched PubMed, EMBASE, and the Cochrane Library in June 2018 for relevant diagnostic studies. Study selection, data extraction, and quality assessment (using the QUADAS-2 criteria) were performed independently by two authors. Methodological variation across the selected studies precluded meta-analysis, so the results were synthesized narratively.
Seven prospective studies involving 50,652 patients (6,760 with ischemic stroke) were included. The treatment threshold ranged from two to four across the studies. Three studies reported diagnostic accuracy at a threshold of two, with a sensitivity above 0.8 and a specificity ranging from 0.32 to 0.68. The diagnostic odds ratio was greater than two (seven studies). The two studies using a treatment threshold of four reported a sensitivity of 0.59 to 0.76 and a specificity of 0.43 to 0.69. One study used a threshold of three, with a sensitivity of 0.79 and a specificity of 0.39.
The CHA2DS2-VASc score may be used to predict ischemic stroke in the non-atrial fibrillation population. Treatment thresholds greater than two provide more optimal diagnostic accuracy, although the predictive performance of the CHA2DS2-VASc score may be better in patients with chronic obstructive pulmonary disease but not AF.
Conotruncal heart defects are considered to be one of the most common types of birth defect worldwide. Genetic disturbances in folate metabolism such as Thymidylate synthase may increase risk for conotruncal heart defects. We evaluated two common Thymidylate synthase polymorphisms, including the 28 bp tandem repeat in the promoter enhancer region of the 5′-untranslated region and the 6 bp deletion in the 3′-untranslated region, as risk factors of conotruncal heart defects including various subtypes of malformations, in a total of 193 mothers with conotruncal heart defect in offspring and 234 healthy controls in the Chinese population. Logistic regression analyses revealed that mothers who were homozygotes with deletion (−/−) had a 1.8-fold (odds ratio: 1.8; 95% confidence interval: 1.0–3.0, p = 0.040) increased risk for conotruncal heart defect in offspring, respectively, when compared with mothers carrying the wild type (+/+) genotype. Consistently, individuals carrying the genotype −/− of the Thymidylate synthase 6 bp deletion also had higher plasma homocysteine levels compared to the mothers carrying the genotype +/+ in the control and conotruncal heart defect groups (p = 0.006 and p = 0.004, respectively). However, our results showed that Thymidylate synthase 28 bp tandem repeat polymorphism was not associated with risk for conotruncal heart defect and plasma homocysteine level. In conclusion, our data suggest that the maternal Thymidylate synthase 6 bp deletion polymorphism might be associated with plasma homocysteine level and risk for conotruncal heart defect in offspring.
Nanopore tuning via atomic layer deposition (ALD) is promising but its conformality on sub-10nm pores and its homogeneity over the whole porous network is still challenging, primarily due to the slow transport within the porous network. Conventional ALD process oftentimes falls into a dilemma: higher temperature and prolonged exposure/purge time are required to overcome the slow transport issue, but higher temperature will cause the instability of surface –OH groups and prolonged exposure/purge time will result in “over purge” at the surface vicinity, leading to another type of non-homogeneity. To resolve this issue, a new dual-stage exposure/purge ALD process was developed. Each exposure/purge step contains a longer exposure/purge stage and a shorter exposure/purge stage, where the longer stage ensures ideal exposure/purge for inner pores, and the shorter stage makes up the surface depletion for the outer pores. By doing so, we’ve been able to extend the ALD nanopore tuning to sub-10nm pores with excellent coating homogeneity and conformality.
The prevalence of CHD has been well described worldwide except in Tibet. This study aimed to illustrate the prevalence and composition of CHD in Tibetan children according to altitude.
Methods and results
In the first part, we prospectively recruited 7088 unselected Tibetan children (4–17 years) from south-west Tibet. The total prevalence of CHD increased from 4.6/1000 below 4200 m to 13.4/1000 above 4700 m, with a female-to-male ratio of 1.3:3.1. The total prevalence and female prevalence of patent ductus arteriosus increased more than 10-fold. Females living above 4700 m had exceptionally high prevalence of patent ductus arteriosus (14.9/1000). The prevalence of atrial septal defect was comparable among different altitudes (3.3–3.8/1000). The prevalence of ventricular septal defect was 1.3/1000 below 4700 m, and no cases were found above this altitude. In the second part, we retrospectively reviewed the clinical data of 383 CHD children in Tibet and 73 children at lower altitudes. The percentage of isolated ventricular septal defect decreased from 54.8 to 3.1%, and the percentage of isolated patent ductus arteriosus increased from 8.2 to 68.4% with elevation. Children living below 4200 m (10.4–13.7%) had a larger proportion of complex CHD than those above this altitude (2.0–3.1%). Of the 20 Tibetan children with complex CHD, 14 (70.0%) lived below 4200 m.
A wide variation in CHD prevalence and composition existed in Tibetan children among different altitudes.
The Myanmar snub-nosed monkey Rhinopithecus strykeri was discovered in 2010 on the western slopes of the Gaoligong Mountains in the Irrawaddy River basin in Myanmar and subsequently in the same river basin in China, in 2011. Based on 2 years of surveying the remote and little disturbed forest of the Gaoligong Mountains National Nature Reserve in China, with outline transect sampling and infrared camera monitoring, a breeding group comprising > 70 individuals was found on the eastern slopes of the Gaoligong Mountains in the Salween River Basin. Given the Critically Endangered status of this primate (a total of < 950 individuals are estimated to remain in the wild), efforts to protect the relatively undisturbed habitat of this newly discovered population and to prevent hunting are essential for the long-term survival of this species.
In this present study, the influence of different casting processes on high cycle fatigue behavior of Mg–10Gd–3Y–0.5Zr magnesium alloy was investigated by using porosity-free low-pressure sand-casting (LPS) bars and gravity permanent mold casting (GPM) ingots. The results show that the fatigue properties of both LPS and GPM Mg–10Gd–3Y–0.5Zr alloy in as-cast condition are determined by Mg matrix and eutectic phase. However, the fatigue property improvement for LPS alloy by T6 heat treatment is significantly superior to that of GPM alloy. The different degree of enhancement of fatigue properties for two conditions of the alloy is related to different crack initiation mechanism. The fatigue crack of the LPS alloy initiates from the free surface of the sample, while the crack of the GPM alloy initiates from porosities or inclusions near the surface of the sample. Meanwhile, the crack of slip band has a crucial effect on the fatigue crack initiation of both as-cast and T6 conditions for LPS alloy.
Our experiments show that external focusing and initial laser energy strongly influences filament generated by the femtosecond Ti–sapphire laser in air. The experimental measurements show the filament length can be extended both by increasing the laser energy and focal length of focusing lens. On the other hand, the plasma fluorescence emission can be enhanced by increasing the laser energy with fixed focal length or decreasing the focal length. In addition, the collapse distance measured experimentally are larger than the calculated ones owing to the group-velocity-dispersion effect. In addition, we find that the line widths of the spectral lines from
is independent of filament positions, laser energies and external focusing.
Crack propagation behaviors in a precracked single crystal Ag under mode I loading at different temperatures are studied by molecular dynamics simulation. The simulation results show that the crack propagation behaviors are sensitive to external temperature. At 0 K, the crack propagates in a brittle manner. Crack tip blunting and void generation are first observed followed by void growth and linkage with the main crack, which lead to the propagation of the main crack and brittle failure immediately without any microstructure evolution. As the temperature gets higher, more void nucleations and dislocation emissions occur in the crack propagation process. The deformation of the single crystal Ag can be considered as plastic deformation due to dislocation emissions. The crack propagation dynamics characterizing the microstructure evolution of atoms around the crack tip is also shown. Finally, it is shown that the stress of the single crystal Ag changes with the crack length synchronously.
There have been inconsistent results published regarding the relationship between dyslipidaemia and an increased risk of colorectal neoplasia (CRN), including colorectal adenoma (CRA) and colorectal cancer (CRC). We conducted a meta-analysis to explore the relationship between dyslipidaemia and CRN.
We identified studies by performing a literature search using PubMed, EMBASE and the Science Citation Index through October 2013.
We analysed thirty-three independent studies reporting the association between CRN and at least one of the selected lipid components, including total cholesterol (TC), TAG, HDL-cholesterol (HDL-C) and LDL-cholesterol (LDL-C).
CRN cases (n 21 809) were identified.
Overall, people with high levels of serum TAG (risk ratio (RR)=1·08; 95 % CI 1·05, 1·12, P<0·00001) and LDL-C (RR=1·07; 95 % CI 1·00, 1·14, P=0·04) presented an increased prevalence of CRN. Subgroup analyses revealed that high levels of serum TC (RR=1·04; 95 % CI 1·01, 1·09, P=0·02), TAG (RR=1·06; 95 % CI 1·03, 1·10, P=0·0009) and LDL-C (RR=1·11; 95 % CI 1·04, 1·19, P=0·003) increased the risk of CRA but not of CRC. No association between serum HDL-C and risk for CRN (including CRA and CRC) was observed.
Both TAG and LDL-C were significantly associated with an increasing prevalence of CRN. High levels of serum TC, TAG and LDL-C were positively associated with CRA but not with CRC. No significant association was observed between levels of serum HDL-C and CRN.
Nosema bombycis, a pathogen of silkworm pebrine, is an obligate unicellular eukaryotic parasite. It is reported that the spore wall proteins have essential functions in the adherence and infection process of microsporidia. To date, the information related to spore wall proteins from microsporidia is still limited. Here, a 44 kDa spore wall protein NbSWP16 was characterized in N. bombycis. In NbSWP16, a 25 amino acids signal peptide and 3 heparin binding motifs were predicted. Interestingly, a region that contains 3 proline-rich tandem repeats lacking homology to any known protein was also present in this protein. The immunofluorescence analysis (IFA) demonstrated that distinct fluorescent signals were detected both on the surface of mature spores and the germinated spore coats. Immunolocation by electron microscopy revealed that NbSWP16 localized on the exospore regions. Finally, spore adherence analysis indicated that spore adherence to host cell was decreased more than 20% by anti-NbSWP16 blocking compared with the negative control in vitro. In contrast with anti-NbSWP16, no remarkable decrement inhibition was detected when antibodies of NbSWP16 and NbSWP5 were used simultaneously. Collectively, these results suggest that NbSWP16 is a new exospore protein and probably be involved in spore adherence of N. bombycis.
The objective of this study was to explore the expression of urotensin II (UII), its receptor (GPR14), and vascular endothelial growth factor (VEGF), as well as their associations in the ischaemic brains of rats with focal cerebral ischaemia, under normal and diabetic conditions.
Diabetes mellitus (DM) was induced by injection of streptozotocin (STZ) into Sprague—Dawley rats. Focal cerebral ischaemia was induced by middle cerebral artery occlusion (MCAO) four weeks after DM onset by STZ. Rats (n=80) were divided into four groups: normal control, DM, MCAO, and DM/MCAO. Immunohistochemistry and reverse-transcriptase-polymerase chain reaction (RT-PCR) were used to detect the expression of UII, GPR14 and VEGF in the diabetic and ischaemic brain.
Expression of UII and GPR14 was increased at mRNA and protein levels in the DM and MCAO group compared with controls. In the DM/MCAO group, expression of UII and GPR14 was increased significantly in the ischaemic brain, and was accompanied by a significantly increased VEGF expression.
Diabetes mellitus was seen to aggravate brain lesions after ischaemia, and UII may have an important role.
The high repetition rate 10 J/10 ns Yb:YAG laser system and its key techniques are reported. The amplifiers in this system have a multi-pass V-shape structure and the heat in the amplifiers is removed by means of laminar water flow. In the main amplifier, the laser is four-pass, and an approximately 8.5 J/1 Hz/10 ns output is achieved in the primary test. The far-field of the output beam is approximately 10 times the diffraction limit. Because of the higher levels of amplified spontaneous emission (ASE) in the main amplifier, the output energy is lower than expected. At the end we discuss some measures that can improve the properties of the laser system.
Spinal surgery is considered a high-risk surgery. To improve the accuracy, stability, and safety of such operations, we report the development of a novel six-degrees-of-freedom Robotic Spinal Surgical System that can assist surgeons in performing transpedicular surgery, one of the most common spinal surgeries. After optimization performed using Response Surface Methodology, the largest available workspace of the robot is determined and is found to easily cover the entire operation area. Cooperative control and navigation-based active control are implemented for different processes of the operation. We propose a hybrid control approach based on the speed and torque interface at the joint level. In this mode, the robot is compliant in Cartesian space, benefitting both the accuracy and efficiency of the operation. A comprehensive assessment index, combining the subjective and objective criteria in terms of positioning and operation efficiency, is proposed to compare the performance of cooperative control in speed mode, torque mode, and hybrid control mode. Active fine adjustment experiments are carried out to verify the positioning accuracy, and the results are found to satisfy the requirements of operation. As an application example, a pedicle screw insertion experiment is performed on a pig vertebral bone, demonstrating the effectiveness of our system.
The fabrication of a temperature sensor based on graphene nanoplatelets (GNPs) is reported. A preheat process was carried out and the micrographs of both original and preheat-treated GNPs are observed and compared. Nonlinear temperature variation of resistance is observed and humidity interference is found to be negligible. Region of 10–60 °C (the linear region) is selected as the sensor range and further studied. High sensitivity of GNPs can be seen and the temperature coefficient of resistance (TCR) of 0.0371 is calculated, higher than that of multiwall carbon nanotubes (MWCNTs) and many other materials reported in references. Great repeatability and small hysteresis are obtained. The time constant of the GNPs film is about 5 s, much shorter than that of MWCNTs film. The result suggests that GNPs have potential applications for use in highly sensitive and fast-response temperature sensors.
Bi2O2CO3/ZnWO4 composite photocatalysts have been successfully synthesized by a mixed calcination method after hydrothermal process. The catalysts were characterized by powder x-ray diffraction, scanning electron microscopy, transmission electron microscopy, high resolution transmission electron microscopy, x-ray photoelectron spectroscopy, and UV-vis diffuse reflectance spectrum. The results showed that the hierarchical Bi2O2CO3/ZnWO4 nanocomposites were obtained by mixed grinding calcination method and Bi2O2CO3 nanospheres grow on the primary ZnWO4 particles. The Bi2O2CO3/ZnWO4 composites exhibit higher photocatalytic activities compared to pure ZnWO4 and Bi2O2CO3 particles under UV light irradiation. Furthermore, the excellent photocatalytic efficiency of the Bi2O2CO3/ZnWO4 composite was deduced closely related to Bi2O2CO3/ZnWO4 heterojunctions whose presence is generally regarded to be a favorable factor for the separation of photogenerated electrons and holes.
Novel europium- and gadolinium-doped bismuth phosphate (Eu/BiPO4 and Gd/BiPO4) microcrystals have been synthesized by a hydrothermal route. The morphologies and optical properties of the as-prepared samples were characterized carefully. Their photocatalytic activities were determined by oxidative decomposition of methylene blue (MB) in aqueous solution. The results revealed that europium and gadolinium doping greatly improves the photocatalytic efficiency of BiPO4 microcrystals. Among these as-prepared europium and gadolinium dopant samples, 1% Eu/BiPO4 and 5% Gd/BiPO4 displayed the highest photocatalytic activity, and the degradation rates are 2 and 2.7 times greater than pure BiPO4, respectively. The photodegradation reactions of MB by Eu- and Gd-BiPO4 followed first-order kinetics. The different photocatalytic mechanisms of Eu/BiPO4 and Gd/BiPO4 photocatalysts are discussed.
Lecanora subjaponica L. Lü & H. Y. Wang from western China is described as new to science. It is the only known Lecanora species having (16–)32-spored asci and it is otherwise characterized by an epruinose, shiny brown apothecial disc, epihymenium lacking granules and the presence of zeorin in addition to atranorin. A worldwide key to the multispored species of Lecanora is also given.