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The short-lived polygamous moth Grapholita molesta (Busck) is an important fruit pest worldwide. Trapping males by synthetic female sex pheromones is not an effective reproductive control strategy. It is important to improve this technology by understanding the mating system of G. molesta. This study investigated mating opportunities and fertile egg production by altering the operational sex ratio, mating age, and male mating history in repeated single mating and multiple mating in the two sexes. Our results showed that the mating and reproductive parameters of virgin males were affected by the number and age of virgin females. Males preferred a female number ≤three-fifths of the male number or ≤2-day-old females, while they discriminated against a female number ≥three times of the male number or ≥5-day-old females. On the other hand, the mating and reproductive parameters of virgin females were affected by repeated single mating and especially multiple mating under different male mating histories. Females preferred once-mated males and discriminated against virgin males. These results indicated that mating systems including more and older virgin females for virgin males and different virgin males for virgin females may be suitable for suppressing G. molesta populations. Hence, these results revealed that preventing mating of virgin adults by synthetic female sex pheromones should be most effective in controlling G. molesta.
The FNDC5 gene encodes the fibronectin type III domain-containing protein 5 that is a membrane protein mainly expressed in skeletal muscle, and the FNDC5 rs3480 polymorphism may be associated with liver disease severity in non-alcoholic fatty liver disease (NAFLD). We investigated the influence of the FNDC5 rs3480 polymorphism on the relationship between sarcopenia and the histological severity of NAFLD. A total of 370 adult individuals with biopsy-proven NAFLD were studied. The association between the key exposure sarcopenia and the outcome liver histological severity was investigated by binary logistic regression. Stratified analyses were undertaken to examine the impact of FNDC5 rs3480 polymorphism on the association between sarcopenia and the severity of NAFLD histology. Patients with sarcopenia had more severe histological grades of steatosis and a higher prevalence of significant fibrosis and definite non-alcoholic steatohepatitis than those without sarcopenia. There was a significant association between sarcopenia and significant fibrosis (adjusted OR 2·79, 95 % CI 1·31, 5·95, P = 0·008), independent of established risk factors and potential confounders. Among patients with sarcopenia, significant fibrosis occurred more frequently in the rs3480 AA genotype carriers than in those carrying the FNDC5 rs3480 G genotype (43·8 v. 17·2 %, P = 0·031). In the association between sarcopenia and liver fibrosis, there was a significant interaction between the FNDC5 genotype and sarcopenia status (P value for interaction = 0·006). Sarcopenia is independently associated with significant liver fibrosis, and the FNDC5 rs3480 G variant influences the association between sarcopenia and liver fibrosis in patients with biopsy-proven NAFLD.
HIV-1 drug resistance can compromise the effectiveness of antiretroviral therapy (ART). A survey of pretreatment HIV-1 drug resistance (PDR) was conducted in Lincang Prefecture of Yunnan Province. From 372 people living with HIV/AIDS initiating ART for the first time during 2017–2018, 322 pol sequences were obtained, of which 11 HIV-1 strain types were detected. CRF08_BC (70.2%, 226/322) was the predominant strain, followed by URF strains (10.6%, 34/322). Drug resistance mutations (DRMs) were detected among 34.2% (110/322) of the participants. E138A/G/K/R (14.3%, 46/322) and V179E/D/T (13.7%, 47/322) were the predominant DRMs. Specifically, E138 mutations commonly occurred in CRF08_BC (19.9%, 45/226). Among the DRMs detected, some independently conferred resistance, such as K65R (1.6%, 5/322), Y188C/F/L (0.9%, 3/322), K103N (0.6%, 2/322) and G190A (0.3%, 1/322), which conferred high-level resistance. The prevalence of PDR was 7.5% (95% CI: 4.6–10.3%) and the prevalence of non-nucleotide reverse transcriptase inhibitor (NNRTI) resistance was 5.0% (95% CI: 2.6–7.4%), which is below the threshold (⩾10%) of initiating a public health response. In conclusion, HIV-1 genetic diversity and an overall moderate level of PDR prevalence were found in western Yunnan. PDR surveillance should be continually performed to decide whether a public health response to NNRTI resistance should be initiated.
Eating disorders have increasingly become a public health concern globally. This study aimed to reveal the burden of eating disorders at the global, regional and national levels using the Global Burden of Disease (GBD) Study 2017 data.
We extracted the age-standardised rates (ASRs) of prevalence and disability-adjusted life years (DALYs) and their 95% uncertainty intervals (UIs) of eating disorders, including anorexia nervosa and bulimia nervosa, between 1990 and 2017 from the GBD 2017 data. The estimated annual percentage changes (EAPCs) were calculated to quantify the secular trends of the burden of eating disorders.
The ASRs of prevalence and the DALYs of eating disorders continuously increased worldwide from 1990 to 2017 by an average of 0.65 (95% UI: 0.59–0.71) and 0.66 (95% UI: 0.60–0.72), respectively. The burden of eating disorders was higher in females than in males, but the increment in ASRs was greater in males than in females over time. In 2017, the highest burden of eating disorders was observed in the high sociodemographic index (SDI) regions, especially Australasia (ASR of prevalence = 807.13, 95% UI: 664.20–982.30; ASR of DALYs = 170.74, 95% UI: 113.43–244.14, per 100 000 population), Western Europe and high-income North America. However, the most significant increment of the burden of eating disorders was observed in East Asia (EAPC for prevalence = 2.23, 95% UI: 2.14–2.32; EAPC for DALYs = 2.22, 95% UI: 2.13–2.31), followed by South Asia. An increasing trend in the burden of eating disorders at the national level was observed among most countries or territories. The countries with the top three highest increasing trends were Equatorial Guinea, Bosnia and Herzegovina and China. Positive associations were found between the burden estimates and the SDI levels in almost all geographic regions during the observed 28-year period. We also found that the human development indexes in 2017 were positively correlated with the EAPCs of the ASRs of prevalence (ρ = 0.222, P = 0.002) and DALYs (ρ = 0.208, P = 0.003).
The highest burden of eating disorders remains in the high-income western countries, but an increasing trend was observed globally and in all SDI-quintiles, especially in Asian regions that were highly populous. These results could help governments worldwide formulate suitable medical and health policies for the prevention and early intervention of eating disorders.
Several observational studies have investigated the association of insomnia with psychiatric disorders. Such studies yielded mixed results, and whether these associations are causal remains unclear. Thus, we aimed to identify the causal relationships between insomnia and five major psychiatric disorders.
The analysis was implemented with six genome-wide association studies; one for insomnia and five for psychiatric disorders (attention-deficit/hyperactivity disorder, autism spectrum disorder, major depressive disorder, schizophrenia, and bipolar disorder). A heterogeneity in dependent instrument (HEIDI) approach was used to remove the pleiotropic instruments, Mendelian randomization (MR)-Egger regression was adopted to test the validity of the screened instruments, and bidirectional generalized summary data-based MR was performed to estimate the causal relationships between insomnia and these major psychiatric disorders.
We observed significant causal effects of insomnia on the risk of autism spectrum disorder and bipolar disorder, with odds ratios of 1.739 (95% confidence interval: 1.217–2.486, p = 0.002) and 1.786 (95% confidence interval: 1.396–2.285, p = 4.02 × 10−6), respectively. There was no convincing evidence of reverse causality for insomnia with these two disorders (p = 0.945 and 0.546, respectively). When insomnia was considered as either the exposure or outcome variable, causal estimates for the remaining three psychiatric disorders were not significant.
Our results suggest a causal role of insomnia in autism spectrum disorder and bipolar disorder. Future disease models should include insomnia as a factor for these two disorders to develop effective interventions. More detailed mechanism studies may also be inspired by this causal inference.
This study examines the impact of employability on turnover intention by differentiating internal and external employability, and considering the possible moderating roles of perceived organizational support (POS) and career orientation. Using a sample of 411 responses to a two-wave questionnaire survey generated from six cities in China, we find that external employability positively influenced turnover intention, but internal employability negatively influenced turnover intention. The results also indicate that POS had a positive moderating effect only on the relationship between external employability and turnover intention. Furthermore, for employees with disengaged career orientation, external employability exerts a strong impact on turnover intention. This study adds to the limited research empirically linking employability and turnover intention, whereas the findings can be used by HRM practitioners to factor in organizational support and career orientation initiatives that improve the retention of employees with high external employability.
The dynamic mechanical force transmitted through microenvironments during tissue formation and regeneration continuously impacts the mechanics of cells and thereby regulates gene and protein expression. The mechanical properties are altered during the process of stem cells differentiating into different lineages. At different stages of differentiation, stem cells display different mechanical properties in response to surrounding microenvironments, which depend on the subcellular structures, especially the cytoskeleton and nucleus. The mechanical properties of the cell nucleus affect protein folding and transport as well as the condensation of chromatin, through which the cell fate is regulated. These findings raise the question as to how cell mechanics change during differentiation. In this study, the mechanical properties of human bone marrow mesenchymal stem cells (hBMSCs) were determined during adipogenic and osteogenic differentiation by atomic force microscopy (AFM). The cytoskeletal structure and the modification of histone were investigated using laser confocal microscope and flow cytometry. The mechanical properties of cell nuclei at different stages of cell differentiation were compared. The stiffness of nuclei increased with time as osteogenesis was induced in hBMSCs. The H3K27me3 level increased during osteogenesis and adipogenesis according to flow cytometry analysis. Our results show conclusively that AFM is a facile and effective method to monitor stem cell differentiation. The measurement of cell mechanical properties by AFM improves our understanding on the connection between mechanics and stem cell fate.
The cao vit gibbon Nomascus nasutus, also known as eastern black crested gibbon, is categorized as Critically Endangered on the IUCN Red List and was considered one of the world's 25 most threatened primates. The only known population occurs along the border between China and Viet Nam. Accurate information on population size and dynamics is critical for the species’ conservation, but population surveys conducted in only one country may over- or underestimate total population size because the home ranges of cao vit gibbon groups often cross the international border. In 2007 and 2016 we conducted two collaborative transboundary censuses of the cao vit gibbon populations in the Trung Khanh Cao Vit Gibbon Species and Habitat Conservation Area in Viet Nam and the Bangliang Gibbon National Nature Reserve in China. The results showed a population size of 102–110 in 2007, which increased to 107–136 in 2016. Our results indicate that previous surveys conducted separately in Viet Nam and China underestimated the global population size of this species. According to our more comprehensive surveys, the gibbon population is increasing slowly. The gibbons and their habitat are legally protected in both countries. Hunting and charcoal making have not been reported in this area since 2007. As habitat carrying capacity is a limiting factor, habitat restoration is required. However, lack of funding to protect the cao vit gibbon remains a challenge.
The aim of the study was to investigate how maternal dietary patterns and maternal/fetal cytokines are associated with birth weight and whether cytokines mediate the association. A total of 469 pregnant women and their children were recruited for this prospective study. Dietary patterns in pregnancy were identified using factor analysis of data from three consecutive 24 h dietary recalls. Maternal and umbilical blood serum cytokines (adiponectin (APN), IL-6 and interferon-γ) were measured via ELISA. Path analysis was used to explore the relationships between maternal diet, cytokines and birth weight. Four dietary patterns were identified: a mainly fruit, dairy products and poultry diet (FDP); a mainly vegetables, beans and pork diet (VBP); a mainly fish, shrimp and soup diet (FS) and a mainly tuber and egg diet (TE). Path analysis showed the order of effects of dietary patterns on birth weight was FS>FDP>TE>VBP (β=0·130, 0·109, –0·094 and 0·046, respectively). Only the TE pattern’s effect was negative. Maternal and fetal APN were positively associated with birth weight (β=0·045 and 0·226, respectively), and they mediated the association between the TE pattern and birth weight (indirect effect was 5·3 %). Maternal IL-6 was negatively associated with birth weight (β=–0·067) and mediated the association between maternal FDP and VBP patterns and birth weight (indirect effects were 10·1 and 100·0 %, respectively). All variables in the path explained 33·6 % of variation. These results suggested that maternal dietary patterns in pregnancy are associated with birth weight and mediated directly and indirectly through some maternal/fetal serum cytokines.
Introduction: White matter hyperintensities (WMHs) were commonly seen in brain magnetic resonance imaging (MRI) of the elderly. Many studies found that WMHs were associated with cognitive decline and dementia. However, the association between WMHs in different brain regions and cognitive decline remains debated. Methods: We explored the association of the severity of WMHs and cognitive decline in 115 non-demented elderly (≥50 years old) sampled from the Wuliqiao Community located in urban area of Shanghai. MRI scans were done during 2009–2011 at the beginning of the study. Severity of WMHs in different brain regions was scored by Improved Scheltens Scale and Cholinergic Pathways Hyperintensities Scale (CHIPS). Cognitive function was evaluated by Mini-Mental State Examination (MMSE) every 2 to 4 years during 2009–2018. Results: After adjusting for confounding factors including age, gender, education level, smoking status, alcohol consumption, depression, hypertension, diabetes, hyperlipidemia, brain infarcts, brain atrophy, apoE4 status, and baseline MMSE score, periventricular and subcortical WMH lesions as well as WMHs in cholinergic pathways were significantly associated with annual MMSE decline ( p < 0.05), in which the severity of periventricular WMHs predicted a faster MMSE decline (–0.187 points/year, 95% confidence interval: –0.349, –0.026, p = 0.024). Conclusions: The severity of WMHs at baseline was associated with cognitive decline in the non-demented elderly over time. Interventions on WMH lesions may offer some benefits for cognitive deterioration.
Underground Nuclear Astrophysics in China (JUNA) will take the advantage of the ultra-low background in Jinping underground lab. High current accelerator with an ECR source and detectors were commissioned. JUNA plans to study directly a number of nuclear reactions important to hydrostatic stellar evolution at their relevant stellar energies. At the first period, JUNA aims at the direct measurements of 25Mg(p,γ)26 Al, 19F(p,α) 16 O, 13C(α, n) 16O and 12C(α,γ) 16O near the Gamow window. The current progress of JUNA will be given.
It has been demonstrated that the introduction of NaCl can significantly improve the quality of monolayer WS2 at the growth temperatures ranging from 700°C to 850°C by atmospheric pressure chemical vapor deposition (APCVD) without the assistant of hydrogen. Here, the influence of NaCl on the nucleation and growth of WS2 has been thoroughly investigated. The morphology and quality of WS2 grown with different temperatures are discussed by optical microscope, Raman and Photoluminescence (PL) spectra. It was found that amount of NaCl can efficiently influence the morphology and quality of WS2 crystals. PL intensity of WS2 crystal increases around three times from the center region to the edge of an individual domain, which may be attributed to the appearance of small triangle hollows formed during the growth at the edge of single crystal WS2.
Outside surface fluctuations of inertial confinement fusion (ICF) capsule greatly affect the implosion performance. An atomic force microscope (AFM)-based profilometer is developed to precisely characterize the capsule surface with nanometer resolution. With the standard nine surface profiles and the complete coverage data, 1D and 2D power spectra are obtained to quantitatively qualify the capsule. Capsule center fast aligning, orbit traces automatic recording, 3D capsule orientation have been studied to improve the accuracy and efficiency of the profilometer.
The effect of nitrogen gas addition in Ar-based double-layer shielding gas on the impact toughness of welded ultra-ferritic stainless steel during an autogenous gas tungsten arc welding (GTAW) process was investigated. The nitrogen behavior was proposed. The microstructure, mechanical properties, and fracture surface morphology of the weld metals have been evaluated. More equiaxed crystals, refined grain, narrow HAZ width, and increased microhardness were produced with nitrogen addition. Experimental findings indicated that nitrogen diffused into HAZ and dissolved into weld pool. The solute distribution was changed thus bringing significant constitutional supercooling and decreased temperature gradient of weld pool, which contributed to fine microstructure. Impact toughness at room temperature was enhanced from 2J to 9J (welds), 5J–13J (HAZ). Ductile fracture zone was produced about 0.3–0.5 mm thickness distance from the weld surface. A significant increased impact toughness of weld metal was due to the refinement of microstructure and element addition.
Potassium titanyl phosphate crystals in both x-cut and z-cut were irradiated with 185 MeV Au ions. The morphology of the resulting ion tracks was investigated using small angle x-ray scattering (SAXS), transmission electron microscopy (TEM), and atomic force microscopy (AFM). SAXS measurements indicate the presence of cylindrical ion tracks with abrupt boundaries and a density contrast of 1 ± 0.5% compared to the surrounding matrix, consistent with amorphous tracks. The track radius depends on the crystalline orientation, with 6.0 ± 0.1 nm measured for ion tracks along the x-axis and 6.3 ± 0.1 nm for those along the z-axis. TEM images in both cross-section and plan-view show amorphous ion tracks with radii comparable to those determined from SAXS analysis. The protruding hillocks covering the sample surface detected by AFM are consistent with a lower density of the amorphous material within the ion tracks compared to the surrounding matrix. Simulations using an inelastic thermal-spike model indicate that differences in the thermal conductivity along the z- and x-axis can partially explain the different track radii along these directions.
Creative conceptual design requires significant previous design knowledge. Case-based reasoning enables learning from previous design experience and has a great potential in supporting creative conceptual design by means of seeking to retrieve, reuse, and revise most appropriate cases to generate inspired solutions. However, traditional case-based reasoning based creative conceptual design models focus on design strategies research, pay little attention to defining a consistent knowledge representation model, and neglect the research to make various types of knowledge retrieval tractable. Faced with such drawbacks, the expected design knowledge cannot be retrieved properly, especially in cases where multidisciplinary knowledge is concerned or exact query terms are absent. In order to solve these issues, this paper presents a combined approach to support creative conceptual design process. First, function–behavior–structure knowledge cell is introduced as a unified consistent design knowledge representation model. Second, a hybrid similarity measure is proposed to increase the overall possibility of obtaining useful design knowledge by considering semantic understanding ability. Third, an intelligent creative conceptual design system has been developed with a case study of a novel insulin pump design to demonstrate its usage, and two experiments are conducted to evaluate the performance of the proposed approach. The results show that the proposed approach outperforms other case-based reasoning based creative conceptual design models.
Direct coagulation casting of alumina via controlled release of high valence counter ions using ammonium polyphosphate (APP) chelate complex as the coagulating agent was proposed. APP chelate complex suspension was prepared from APP and calcium chloride. Calcium used as high valence counter ions was chelated by APP. The average particle size of the chelate complex is 0.13 μm with a narrow particle size distribution which is close to the size of alumina particles. Glycerol diacetate was used to tailor the pH value of the suspension by hydrolysis which produces acetic acid. The lowering of the pH value helps to decompose the chelate complex, and enhance to release the calcium chelated. It is indicated that the viscosity of the suspensions with the addition of APP chelate complex suspension and glycerol diacetate increases to approximately 20 Pa s after heating at 40–70 °C for 1.5–5 h, which is high enough to coagulate the suspension. 55 vol% alumina suspension with a addition of 3 vol% APP chelate complex suspension and 5 vol% glycerol diacetate treated at 60 °C could coagulate completely within 2 h with a compressive strength of 2.1 MPa. Dense alumina with a relative density of above 97% and a flexural strength of 388 ± 23 MPa can be prepared by this method from 55 vol% alumina suspensions without a burnout process.