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This study aimed to determine whether increased carotenoids intake was associated with reduced risk of gestational diabetes mellitus (GDM). We performed a cross-sectional analysis using data from Tongji Maternal and Child Health Cohort study. The dietary carotenoids intake of 1978 pregnant women was assessed using a researcher-administered FFQ before undertaking an oral glucose tolerance test at 24–28 weeks. Multivariate logistic and linear regression analyses were used to obtain the effect estimates. Participants in the highest quartile of lycopene intake showed a lower risk of GDM (OR 0·50; 95 % CI 0·29, 0·86; Pfor trend = 0·007) compared with those in the lowest quartile; each 1 mg increase in lycopene consumption was associated with a 5 % (95 % CI 0·91, 0·99; Pfor trend = 0·020) decrease in GDM risk. No significant association was found between α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin intake and GDM risk. Multiple linear regression analysis suggested an inverse association between lycopene intake and fasting blood glucose (FBG) (Pfor trend < 0·001); each 1 mg increase in lycopene intake was associated with 0·005 (95 % CI 0·002, 0·007; Pfor trend < 0·001) mmol/l decrease in FBG. Interaction analysis indicated consistent effect on each age or pre-BMI subgroup; however, a stronger protective effect of lycopene intake against GDM was observed among primigravid women (OR 0·20; 95 % CI 0·07, 0·55 in the highest v. the lowest quartile of intake; Pfor interaction = 0·036). In conclusion, dietary lycopene intake was mainly assumed via reducing FBG to decrease GDM risk, and the protection was relatively increased among primigravid women.
Associations have been shown between father’s absence and menarcheal age, but most studies have focused on absence resulting from divorce, abandonment or death. Little research has been conducted to evaluate the effect on menarcheal age of paternal absence through migrant work. In a sample of 400 middle school students, this study examined the association between paternal migrant work and menarcheal age against a backdrop of extensive rural-to-urban migration in China. Data were collected through a self-reported questionnaire, including social-demographic characteristics, aspects of family relationships, information about father’s migrant work and age at menarche. After adjusting for BMI, parent marital status and perceived relationship with mother, lower self-perceived quality of father–daughter relationship (both ‘father present, relationship poor’ and ‘father absent, relationship poor’) and lower frequency of contact with the father were associated with higher odds for early menarche. These findings suggest that the assumption that father’s absence for work influences the timing of menarche needs to be examined in the context of the quality of the father–daughter relationship and paternal care, which appear to play a critical role in the timing of menarche. These findings also emphasize the importance of enhancing paternal involvement and improving father–daughter relationships in the development of appropriate reproductive strategy in daughters.
A field study to optimize the nitrogen (N) top-dressing mode of panicle fertilization and improve rice yields was conducted in mid-eastern China. Japonica cultivar Yunongjing-6 was grown and panicle N fertilizer was applied at the beginning of the inverted fourth leaf stage using three different modes: manual broadcast application (BA) on the soil surface as a control treatment, deep application during ditching at a depth of 15 cm (DD) and manual BA on the soil surface during deep ditching (BAD). The activity of soil enzymes, including invertase, urease, phosphatase and catalase, was increased significantly at the jointing, booting and grain-filling stages with the DD and BAD treatments compared with the traditional BA mode. The DD and BAD treatments also increased basal internode and neck-panicle internode bleeding intensity. The DD treatment gave the highest crop yield, increasing the yield by 0.63 and 0.31 t/hm2 in 2011 and 2012, respectively, compared with BA. The results suggest that ditching during panicle N fertilizer application after sun-drying of the fields increases rice yields, most likely by improving the activity of soil enzymes and enhancing the physiological activity of roots and grain weight.
The aims of this systematic review were to examine the effects of the overall and the different types of the interventions on the do-not-resuscitate (DNR) designation and the time between DNR and death among cancer patients.
Data were searched from the databases of PubMed, CINAHL, EMbase, Medline, and Cochrane Library through 2 November 2017. Studies were eligible for inclusion if they were (1) randomized control trails, quasi-experimental study, and retrospective observational studies and (2) used outcome indicators of DNR designation rates. The Effective Public Health Practice Project tool was used to assess the overall quality of the included studies.
The 14 studies with a total of 7,180 participants were included in this review. There were 78.6% (11 of 14) studies that indicated that the interventions could improve the DNR designation rates. Three types of DNR interventions were identified in this review: palliative care unit service, palliative consultation services, and patient-physician communication program. The significant increases of the time between DNR designation and death only occurred in a patient-physician communication program.
Significance of results:
The palliative care unit service provided a continuing care model to reduce unnecessary utilization of healthcare service. The palliative consultation service is a new care model to meet the needs of cancer patients in non-palliative care unit. The share decision-making communication program and physician's compassion attitudes facilitate to make DNR decision early. The individualized DNR program needs to be developed according to the needs of cancer patients.
A novel synthetic air data estimation method without using air data sensors is presented, and the method only relies on the information from the Navigation System (NS) and Flight Control System (FCS). The aircraft's aerodynamic model is also required to make a connection between the FCS control parameters and the NS measurements. The airspeed, angle of attack and sideslip, angular velocity and wind speed are defined as state vectors, and state equations are established through the aircraft's aerodynamic model and dynamics. Linear velocity and angular velocity provided by the navigation system are considered as the measurement vector. To deal with variable wind fields, a novel Initialised Three-step Extended Kalman Filter (ITEKF), which considers the wind speed as an unknown input, is developed to track the variation of wind speed. Simulation results based on a Generic Hypersonic Vehicle (GHV) model are presented and compared with an existing method. Factors affecting the method's accuracy include the navigation system accuracy and the aerodynamic model error, are also discussed.
Parents commonly fail to correctly recognize the weight status of their child. Whether parental perception of child weight is associated with weight-related parenting behaviours and child behaviours is unclear. The present study aimed to investigate the distribution of parental perception of child weight and its associations with weight-related parenting behaviours and child behaviours in China.
Seven provinces in China.
A total of 47 417 children aged 6–17 years and their parents were included from a national survey in 2013. Parental perception of child weight, weight-related parenting behaviours and child behaviours were self-reported. Child’s weight and height were objectively measured.
A total of 30·5 % of parents underestimated and 8·7 % overestimated the child’s weight. Parental underestimation was more common among younger children, boys and children with a lower BMI Z-score. Parents who perceived that their child had a healthy weight (accurately or inaccurately) were more likely to prepare breakfast for the child, exercise with him/her, set apart his/her exercise time, restrict his/her screen time, and were less likely to store soft drinks for the child. Children perceived to have a healthy weight, regardless of their actual weight status, behaved healthier on dietary intake, physical activity and homework time.
Parental underestimation of their child’s weight was prominent in China, especially among younger children, boys and children with a lower BMI Z-score. Parental recognition of their child being overweight did not appear to translate into healthy changes in weight-related parenting behaviours or child behaviours.
Attention-deficit hyperactivity disorder (ADHD) increases the risk of suicidal behaviours through psychiatric comorbidities; however, a significant direct association has not been observed between ADHD and suicide attempts.
To evaluate the risk of suicide attempt in adolescents and young adults with ADHD.
Using a nationwide, population-based insurance claims database, this longitudinal cohort study enrolled 20 574 adolescents and young adults with ADHD and 61 722 age- and gender-matched controls between 2001 and 2009. Any suicide attempt was identified from enrolment to 31 December 2011. The association between ADHD medications and the likelihood of suicide attempt was assessed.
ADHD was an independent risk factor for any suicide attempt (hazard ratio = 3.84, 95% CI = 3.19–4.62) and repeated suicide attempts (hazard ratio = 6.52, 95% CI = 4.46–9.53). Subgroup analyses of men, women, adolescents and young adults demonstrated the same trend. Methylphenidate or atomoxetine treatment did not increase the risk of suicide attempt or repeated suicide attempts. Long-term methylphenidate treatment was associated with a significantly decreased risk of repeated suicide attempts in men (hazard ratio = 0.46, 95% CI = 0.22–0.97).
ADHD was a risk factor for suicide attempt and a stronger predictor of repeated suicide attempts, independent of comorbidities. Further investigation is warranted to explore the mechanism underlying the association between ADHD and suicidal behaviours.
Apathy is a condition characterized by a lack of motivation that manifests in emotional, behavioral, and cognitive domains. Although previous studies have indicated that apathy is associated with frontal lesions, few studies have focused on the different subdomains of apathy, and no in vivo human biochemical data have been obtained to examine the neurochemical changes related to apathy in patients with Alzheimer's disease (AD). Thus, we investigated the frontal neurochemical alterations related to apathy among patients with AD using proton magnetic resonance spectroscopy (1H MRS).
Apathy was assessed through the Apathy Evaluation Scale (AES). 1H MRS was performed to measure neurochemical metabolite levels in the anterior cingulate region and right orbitofrontal region. Associations between neurochemical metabolites and the total score and subscores of each domain of the AES were analyzed.
Altogether, 36 patients completed the study. Patients with lower N-acetylaspartate/creatine ratios (NAA/Cr) in the anterior cingulate region demonstrated higher total apathy scores (β = −0.56, p = 0.003) with adjustments for age, gender, educational level, dementia severity, and depression severity. In a further analysis, a lower NAA/Cr in the anterior cingulate region was associated with all subdomains of apathy, including cognition (β = −0.43, p = 0.028), behavior (β = −0.55, p = 0.002), and emotion (β = −0.50, p = 0.005). No statistically significant associations were discovered in the right orbitofrontal region.
Our results suggest that apathy, in each of its cognitive, behavioral, or emotional subdomains is associated with brain neurochemical alterations in the anterior cingulate region. Abnormal neuronal integrity over the anterior cingulate cortex may exhibit a central role in causing all aspects of apathy in patients with AD.
During 1997–2012 we conducted a nationwide camera-trapping survey and assessed the availability of prey and habitat for the clouded leopard Neofelis nebulosa in Taiwan. We surveyed 1,249 camera-trap sites over 113,636 camera-trap days, from the seashore to an altitude of 3,796 m and covering various types of vegetation. No clouded leopards were photographed during 128,394 camera-trap days, including at 209 sites in other studies, confirming the presumed extinction of clouded leopards in Taiwan. Assessment of the prey base revealed altitudinal distribution patterns of prey species and prey biomass. Areas at lower altitudes and with less human encroachment and hunting supported a higher prey biomass and more of the typical prey species of clouded leopards. Habitat analysis revealed 8,523 km2 of suitable habitat but this was reduced to 6,734 km2 when adjacent areas of human encroachment were subtracted. In the absence of hunting and large mammalian carnivores the major prey of clouded leopards in Taiwan, such as Formosan macaques Macaca cyclopis, Reeves's muntjacs Muntiacus reevesi, Formosan serow Capricornis swinhoei and sambar Rusa unicolor, could become over-abundant. Thus, it is important to address the cascading effect of the disappearance of top-down predator control. Our assessment indicated that, with proper regulation of hunting, habitat restoration and corridor improvement, it may be possible to reintroduce the clouded leopard.
We present a plasmonic splitter based on metal-insulator-metal (MIM) structure. This splitter consists of two parallel waveguides and two resonators. One resonator is a ring tangentially connected with the two waveguides, and the other resonator is a semi-ring directly connected to the lower waveguide. The finite-difference time-domain (FDTD) method is used to numerically analyze the transmittance spectra of the splitter. The results show that this splitter is a beam splitter when the wavelength of the incident wave is around 1355 nm or 1553 nm. This splitter can also be regarded as a power splitter. To our knowledge, this is the first designed surface plasmon polaritons (SPPs) splitter which utilize both the communication wavelengths at around 1310 nm and 1550 nm. This characteristics show potential applications in future optical circuits.
Unawareness of deficits is common and is associated with poor outcomes in Alzheimer's disease (AD); however, little is known about correlated neurobiochemical changes.
Proton magnetic resonance spectroscopy was used to examine neurobiochemical correlates of unawareness of deficits as assessed by the Dementia Deficit Scale in 36 patients with AD. Magnetic resonance spectroscopy spectra were acquired from the anterior cingulate area and right orbitofrontal area. Concentrations of N-acetyl-aspartate (NAA), total creatine, and other neurometabolites were calculated.
Nineteen (52.8%) participants had relative unawareness of deficits. This condition was negatively correlated with NAA/creatine in the anterior cingulate area (β = −0.36, p = 0.025) and positively correlated with NAA/creatine in the right orbitofrontal area (β = 0.41, p = 0.009) after controlling for dementia severity.
These findings suggest unawareness of deficits in AD was associated with the altered neurochemical metabolites in the anterior cingulate area and right orbitofrontal area. However, the two areas might have opposite neuronal functions in unawareness of deficits.
An approach formulated by vector algebra is proposed to deal with great circle sailing problems. Using the technique of the fixed coordinates system and relative longitude concept, derivations of formulae for this approach are simpler than those of the conventional methods. Due to fixing the initial great circle course, the great circle track (GCT) is determined. Since the course is fixed (known as “COFI” in this paper), the proposed approach, which we have named the “COFI method”, can directly calculate the waypoints along the GCT. It is considered that the COFI method is a more understandable and straightforward method to solve waypoint problems than older approaches in the literature. Based on the COFI method, a program has been developed for the navigator. In addition, the spherical triangle method with respect to the equator crossing point (STM-E) is developed by supplemental theorem. Several examples are demonstrated to validate the proposed COFI method and STM-E.
Background: Though multiple policies have been implemented, the cigarette control in China is still facing a great challenge. At the same time, alcohol drinking has increasingly become a public health problem. Considering cigarette smoking and alcohol drinking often co-occur, a few studies tested the covariance of these phenotypes. However, the genetic and environmental correlation between them among Chinese population has not been determined. The main aim of this study is to fill this gap. Methods: From the Chinese National Twin Registry, we obtained the data on cigarette smoking and alcohol drinking behaviors. The ordinal bivariate genetic analysis was performed to fit the categorical variables. After identifying the best decomposition among the Cholesky, common, and independent pathway model, we established the most parsimonious submodel. Results: The correlation between current tobacco and alcohol use could be explained by Cholesky model. The shared environmental variances for both phenotypes were dropped to construct the most parsimonious submodel. Furthermore, the most parsimonious submodel showed a moderate correlation (0.32, 95%CI = 0.17 – 0.46) between the genetic components and a negligible non-shared environmental correlation. Conclusion: As the first bivariate genetic analysis on current tobacco smoking and current alcohol drinking in China, this study suggested a common genetic vulnerability to tobacco and alcohol use in male twins. Further studies should be carried out to track the pertinent genes that are related to the comorbidity of smoking and drinking in Chinese population. Another urgent need is to recognize the behavior-specific environmental risk factors.
The effect of direct current (dc) substrate bias on the promotion of nanocrystallization in Si network has been studied, specifically within He-diluted SiH4 plasma in radio frequency (RF)-plasma-enhanced chemical vapor deposition. In view of organizing nanocrystallinity, controlled transmission of energy to the growing surface is needed and that is obtainable from metastable helium (He*) bombardment and, in particular, ionic helium (He+) bombardment under negative substrate bias. The structural morphology has been adequately regulated to a homogeneous network restraining from an exclusive columnar structure that is coherent to low-temperature growth. Notable improvements in the film quality in terms of enhanced crystallinity with low hydrogen content as well as reduced incubation volume, bulk void, and surface roughness have been demonstrated, even at low substrate temperature and low RF power. Use of appropriate dc substrate-bias has been identified as a supplementary parameter efficiently organizing the growth, making it more device-friendly.
We give an overview of the open-boundary planar supercell stack method (OPSSM), as a means for treating 3D quantum transport in mesoscopic tunnel structures. The flexibility of the method allows us to examine a variety of physical phenomena relevant to quantum transport. In this work we focus on the effects of interface roughness and embedded nanostructures in tunnel devices. Four representative applications of OPSSM are discussed: (1) interface roughness in double barrier resonant tunneling structures, (2) self-organized InAs quantum dot insertions in GaAs/AlAs double barrier structures, (3) tunneling characteristics of ultra-thin oxides with interface roughness, and, (4) embedded quantum wire model of dielectric breakdown. These examples demonstrate scattering and localization effects under different biasing conditions.
Barium strontium titanate (Ba0.7Sr0.3TiO3, BST) ceramics prepared by a reaction-sintering process were investigated. The mixture of raw materials of stoichiometric Ba0.7Sr0.3TiO3 was pressed and sintered into ceramics without any calcination stage involved. Perovskite BST ceramics were obtained after sintered at 1330–1370°C for 2–6 h. For 6 h soak time, a density value 5.68g/cm3 (99.8% of the theoretic value) was obtained at 1350°C sintering. Grains of sizes between 2μm and 15μm were formed after 1330–1370°C sintering for 2–6 h. A diffused ferroelectric-paraelectric transition was observed in pellets sintered at 1330°C for 2 h and disappeared at a longer soak time or a higher sintering temperature.