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The aim of this study is to explore the influence of tea consumption on diabetes mellitus in Chinese population. This multicenter, cross-sectional study was conducted in eight sites from south, east, north, west and middle regions in China by enrolling 12,017 subjects aged 20–70. Sociodemographic and general information were collected by standardized questionnaire. Standard procedure was used to measure anthropometric characteristics and obtain blood samples. The diagnosis of diabetes was determined using a standard 75-g oral glucose tolerance test. In the final analysis, 10,825 participants were included, and multiple logistic models and interaction effect analysis were applied for assessing the association between tea-drinking with diabetes. Compared with non-tea drinkers, the multivariable-adjusted odds ratios for newly-diagnosed diabetes were 0.80(0.67, 0.97), 0.88(0.71, 1.09) and 0.86(0.67, 1.11) for daily tea-drinkers, occasional tea-drinkers and seldom tea-drinkers, respectively. Furthermore, drinking tea daily was related to decreased risk of diabetes in female by 32%, elderly (>45y) by 24% and obese (BMI>30kg/m2) by 34%. Moreover, drinking dark tea was associated with reduced risk of diabetes by 45% [OR: 0.55 (0.42, 0.72), P < 0.01]. The results imply that drinking tea daily was negatively related to risk of diabetes in female, elderly and obese people. In addition, drinking dark tea was associated with decreased risk of T2DM.
Maternal supraphysiological estradiol (E2) environment during pregnancy leads to adverse perinatal outcomes. However, the influence of oocyte exposure to high E2 levels on perinatal outcomes remains unknown. Thus, a retrospective cohort study was conducted to explore the effect of high E2 level induced by controlled ovarian stimulation (COH) on further outcomes after frozen embryo transfer (FET). The study included all FET cycles (n = 10,581) between 2014 and 2017. All cycles were categorized into three groups according to the E2 level on the day of the human Chorionic Gonadotropin trigger. Odds ratios (ORs) and their confidence intervals (CIs) were calculated to evaluate the association between E2 level during COH and pregnancy outcomes and subsequent neonatal outcomes. From our findings, higher E2 level was associated with lower percentage of chemical pregnancy, clinical pregnancy, ongoing pregnancy, and live birth as well as increased frequency of early miscarriage. Preterm births were more common among singletons in women with higher E2 level during COH (aOR1 = 1.93, 95% CI: 1.22–3.06; aOR2 = 2.05, 95% CI: 1.33–3.06). Incidence of small for gestational age (SGA) was more common in both singletons (aOR1 = 2.01, 95% CI: 1.30–3.11; aOR2 = 2.51, 95% CI: 1.69–3.74) and multiples (aOR1 = 1.58, 95% CI: 1.03–2.45; aOR2 = 1.99, 95% CI: 1.05–3.84) among women with relatively higher E2 level. No association was found between high E2 level during COH and the percentage of macrosomia or large for gestational age. In summary, oocyte exposure to high E2 level during COH should be brought to our attention, since the pregnancy rate decreasing and the risk of preterm birth and SGA increasing following FET.
The Sichuan–Yunnan–Guizhou (SYG) Pb–Zn metallogenic province is one of the most productive areas of Pb–Zn resources in China. The Fule deposit occurs in Permian carbonate and contains Pb–Zn reserves exceeding 1 Mt. To investigate the sulphur source, in situ S isotopic analysis of sphalerite and pyrite was carried out using nanoscale secondary-ion mass spectrometry. The results show that the δ34S values of the sulphide minerals range from +16.1‰ to +23.0‰, higher than that of marine sulphates hosted in Permian carbonate rocks (+11‰), but similar to that of sulphates over a broader area (+12.9‰ to +25.9‰). The sulphates in the regional rocks could therefore represent an important source of S for the Fule deposit via thermochemical sulphate reduction. The S source of the Fule deposit is different from those of most other Pb–Zn deposits in the SYG Pb–Zn mineralization province, which were mainly derived from the ore-bearing strata. The δ34S values of the early to late generations and some single sulphide crystals from the cores to rims show a slight increasing trend, implying that partial Rayleigh fractionation took place in the Fule deposit. It is suggested that the Fule sulphide precipitation resulted from the mixing of a metalliferous fluid with a H2S-rich fluid derived from the regional strata. Combining the geology, mineralogy and S isotope results with previous Pb isotope studies, it is suggested that the Fule deposit should be attributed to a Mississippi Valley type deposit.
The three-dimensional flow characteristics of the compressible vortex ring generated by under-expanded circular jets with two typical pressure ratios, i.e.
(moderate) and 4.0 (high), are investigated numerically with the use of large-eddy simulations. Our results illustrate that these two pressure ratios correspond to different shock structures (shock cell and Mach disc, respectively) within the jet. These two typical types of flow structures and characteristics are discussed and validated with experiments, and the different generation mechanisms of the secondary vortex rings are compared. Moreover, detailed information about the evolution of the secondary vortex ring, primary vortex ring and turbulence transition features, including the radial and azimuthal modes, is investigated. The geometric features and mixing effects of the jets are also explored.
Maternal one-carbon metabolism during pregnancy is crucial for fetal development and programming by DNA methylation. However, evidence on one-carbon biomarkers other than folate is lacking. We, therefore, investigated whether maternal plasma methyl donors, that is, choline, betaine and methionine, are associated with birth outcomes. Blood samples were obtained from 115 women during gestation (median 26·3 weeks, 90 % range 22·7–33·0 weeks). Plasma choline, betaine, methionine and dimethylglycine were measured using HPLC-tandem MS. Multivariate linear and logistic regression models were used to estimate the association between plasma biomarkers and birth weight, birth length, the risk of small-for-gestational-age and large-for-gestational-age (LGA). Higher level of maternal betaine was associated with lower birth weight (–130·3 (95 % CI –244·8, –15·9) per 1 sd increment for log-transformed betaine). Higher maternal methionine was associated with lower risk of LGA, and adjusted OR, with 95 % CI for 1 sd increase in methionine concentration was 0·44 (95 % CI 0·21, 0·89). Stratified analyses according to infant sex or maternal plasma homocysteine status showed that reduction in birth weight in relation to maternal betaine was only limited to male infants or to who had higher maternal homocysteine status (≥5·1 µmol/l). Higher maternal betaine status was associated with reduced birth weight. Maternal methionine was inversely associated with LGA risk. These findings are needed to be replicated in future larger studies.
Information systems (IS) have facilitated workflow in the health care system for years. However, the utilization of IS in disaster medical assistance teams (DMATs) has been less studied.
In Taiwan, we started a program in 2008 to build up an information system, MEDical Assistance and Information Dashboard (MED-AID), to improve the capability and increase the efficiency of our national DMAT.
Method: The mission of our national DMAT was to provide acute trauma care and subacute outpatient care in the field after an emergency event (e.g., earthquakes). We built the IS through a user-oriented process to fit the need of the DMAT. We first analyzed the response work in the DMAT missions and reviewed the current paperwork. We evaluated the eligibility and effectiveness of the core functions of DMATs by experts in Taiwan and then developed the IS. The IS was then tested and revised each year in two table-top exercises and one regional full-scale exercise by the DMAT staffs who came from different hospitals in Taiwan.
During the past 10 years, we identified several core concepts of IS of DMAT: patient tracking, medical record, continuity of care, integration of referral resources, disease surveillance, patient information reporting, and medical resources management. The application of the IS facilitate the DMAT in providing safe patient care with continuous recording and integrate patient referral resources based on geographic information. The IS also help the planning in real-time disease surveillance and logistic function in the medical resources monitoring.
Information systems could facilitate patient care and relieve the workload on information analysis and resources management for DMATs.
This study investigates numerically the performance of applying aerospike nozzle in a hydrogen peroxide mono-propellant propulsion system. A set of governing equations, including continuity, momentum, energy and species conservation equations with extended k-ε turbulence equations, are solved using the finite-volume method. The hydrogen peroxide mono-propellant is assumed to be fully decomposed into water vapor and oxygen after flowing through a catalyst bed before entering the nozzle. The aerospike nozzle is expected to have high performance even in deep throttling cases due to its self-compensating characteristics in a wide range of ambient pressure environments. The results show that the thrust coefficient efficiency (Cf,η) of this work exceeds 90% of the theoretical value with a nozzle pressure ratio (PR) in the range of 20 ~ 45. Many complex gas dynamics phenomena in the aerospike nozzle are found and explained in the paper. In addition, performance of the aerospike nozzle is compared with that of the bell-shape nozzle.
Ga2−xFexO3 (GFO) bulks with x from 0.7 to 1.3 have been fabricated using the classic solid-state route. The structural, optical, and magnetic properties have been investigated systematically. X-ray diffraction spectra and FULLPROF profile fitting indicate that GFO bulks belong to the orthorhombic structure with the space group Pc21n. Phase separation appears at the Fe content of x = 1.3. The optical bandgap decreases almost linearly with the increase of iron content, which means that the bandgap of GFO bulks can be controlled by adjusting the Fe content in the samples. The magnetic property measurements suggest that GFO is ferromagnetic, and the magnetic properties are enhanced compared with other reported works, exhibiting the application in ferromagnetic semiconductors devices.
Three types of multilayer flyer energy conversion elements (MFECEs) through integrating different laser pulse absorption/ablation layer of nano-film materials into a laser-driven flyer plates between thermal barrier of alumina and transparent substrate have been investigated in this study. The relationships among the velocity of flyer plates, initiation performance of hexanitrostilbene (HNS-IV), and initiation energy were analyzed, comparing with single-layer Al flyer plate. The photonics Doppler velocimetry and James criterion were utilized in the experiments to characterize the velocity of flyer plates and shock initiation of laser-driven flyer detonator, respectively. The surface reflectivity measurements of the Al, C/Al and Mg/Al layers were performed using laser reflectivity. HNS-IV without initiation was analyzed by scanning electron microscope and energy dispersive spectrometer. Caused by aluminum/alumina/aluminum (Al/Al2O3/Al) flyer plate, the residual fragments were found in the pit on the surface of charge. The results obtained were shows that three types of multilayer flyer plates can initiate HNS-IV successfully under the lower laser pulse energy, although all four kinds of flyer plates have successfully initiated HNS-IV with laser pulse energy in the range of 53.80–166.80 mJ. Changing the ablation layer structure and adding thermal insulation layer to the multilayer flyer plates, reduces the shock initiation laser pulse energy of HNS-IV to 53.80 mJ. The laser-driven flyer detonator has significant advantages in providing safety and reliability, especially in a strong electromagnetic environment. The MFECEs of laser-driven flyer detonator exhibited a high level of integration and proved to have promoted laser-driven energy coupling rate, which can significantly be used to improve the performance of the laser-driven flyer detonator in military and civilian applications.
The aim of this study was to explore perinatal and early postnatal outcomes in fetuses with prenatally diagnosed d-transposition of the great arteries and impacts of standardised prenatal consultation.
All fetuses with prenatally diagnosed d-transposition of the great arteries prospectively enrolled at South China cardiac centre from 2011 to 2015. Standardised prenatal consultation was introduced in 2013 and comprehensive measures were implemented, such as establishing fetal CHD Outpatient Consultation Service, performing standard prenatal consultation according to specifications, and establishing a multidisciplinary team with senior specialists performing in-person consultations. Continuous follow-up investigation was conducted. Perinatal and postnatal outcomes were compared before and after consultation including live birth, elective termination of pregnancy, spontaneous fetal death, stillbirths, referral for surgery, and survival.
In all, 146 fetuses were enrolled with 41 (28%) lost to follow-up. Among 105 remaining fetuses, 29 (28%) were live births and 76 (72%) were terminated. After consultation, live birth rate was higher (50 versus 33%) and termination rate was lower (50 versus 76%), although there was no statistical significance. Excluding three live births without postnatal d-transposition of the great arteries, 65% (17/26) underwent arterial switch operation within 30 days. A total of three in-hospital deaths occurred and during the 10-month follow-up period, one death was observed. In one case, the switch procedure was performed at 13 months and the infant survived. Out of eight infants without arterial switch operation, two died.
Live birth rate increased after consultation; however, termination remained high. Combining termination, patients without arterial switch operation, and operative mortality, outcomes of d-transposition of the great arteries infants can be improved. Standard consultation, multidisciplinary collaboration, and improved perinatal care are important to improve outcomes.
This article outlines the evolution of a rescue team in responding to adenovirus prevention with a deployable field hospital. The local governments mobilized a shelter hospital and a rescue team consisting of 59 members to assist with rescue and response efforts after an epidemic outbreak of adenovirus. We describe and evaluate the challenges of preparing for deployment, field hospital maintenance, treatment mode, and primary treatment methods. The field hospital established at the rescue scene consisted of a medical command vehicle, a computed tomography shelter, an X-ray shelter, a special laboratory shelter, an oxygen and electricity supply vehicle, and epidemic prevention and protection equipment. The rescue team comprised paramedics, physicians, X-ray technicians, respiratory therapists, and logistical personnel. In 22 days, more than 3000 patients with suspected adenovirus infection underwent initial examinations. All patients were properly treated, and no deaths occurred. After emergency measures were implemented, the spread of adenovirus was eventually controlled. An emergency involving infectious diseases in less-developed regions demands the rapid development of a field facility with specialized medical personnel when local hospital facilities are either unavailable or unusable. An appropriate and detailed prearranged action plan is important for infectious diseases prevention. (Disaster Med Public Health Preparedness. 2018;12:109–114)
A compact three-dimensional (3D) circularly polarized (CP) microstrip antenna is presented in this paper. The antenna adopts three low-cost printed circuit boards to form an integrated and closed 3D structure, and the radiation patch and the feed patches are etched on the surface of that. A crossed slot is cut on the radiation patch to miniaturize the antenna, and triangular feed patches are introduced to increase the bandwidths. In addition, because of the utilization of a low-loss series feed line, the antenna has a high efficiency of more than 95%. A prototype of the antenna is measured to validate the method. The dimensions of the antenna is 0.064λ × 0.36λ (λ is the wavelength in free space at 1.2 GHz). The results indicate that the impedance bandwidth for voltage standing wave ratio ≤ 2 reaches 23%, and the bandwidth for axial ratio (AR) ≤ 3 dB reaches 10.1%. In the overlap band, the gains are > 4.5dBic. Additionally, the 3 dB beamwidth is more than 114°, and the beamwidth for AR ≤ 3 dB is more than 131° at 1.2 GHz.
A compact hybrid rocket motor design that incorporates a dual-vortical-flow (DVF) concept is proposed. The oxidizer (nitrous oxide, N2O) is injected circumferentially into various sections of the rocket motor, which are sectored by several solid fuel “rings” (made of hydroxyl-terminated polybutadiene, HTPB) that are installed along the central axis of the motor. The proposed configuration not only increases the residence time of the oxidizer flow, it also implies an inherent “roll control” capability of the motor. Based on a DVF motor geometry with a designed thrust level of 11.6 kN, the characteristics of the turbulent reacting flow within the motor and its rocket performance were analyzed with a comprehensive numerical model that implements both real-fluid properties and finite-rate chemistry. Data indicate that the vacuum specific impulse (Isp) of the DVF motor could reach 278 s. The result from a preliminary ground test of a lab-scale DVF hybrid rocket motor (with a designed thrust level of 3,000 N) also shows promising performance. The proposed DVF concept is expected to partly resolve the issue of scalability, which remains challenging for hybrid rocket motors development.
A novel small embedded long-term evolution/wireless wide area network (LTE/WWAN) antenna integrated with the keyboard ground plane in a laptop computer is presented. The antenna is installed on a notched region (40 × 8 mm2) of the keyboard ground plane at a distance of 10 mm from the laptop computer hinge. A coupled-fed loop antenna was used because of its suitability for integration with the ground plane and achieving wide operating bands. This antenna can not only be configured to have a compact configuration but also be designed to excite several resonant modes of the hinge slot between the display ground plane and the keyboard ground plane. The proposed antenna comprises a hook-shaped strip and a shorted strip, which together form a coupled-fed loop that not only has a compact size when printed on a 0.8-mm-thick FR4 substrate 40 × 8 mm2 in size but also provides eight-band LTE/WWAN operation. The proposed antenna can cover LTE/WWAN operation in the 698–960 and 1710–2690 MHz bands. Details of the antenna structure are provided here. The proposed antenna was fabricated and tested, and measurement and simulation results are presented. The measured antenna efficiency was approximately 45–80% in the lower band and approximately 52–75% in the upper band.
237Np (≃2.14 × 106 yr half-life) is potentially applicable in studies on nuclear safeguards and radioactive waste migration. The atomic ratio of 237Np/U in nature is 10−12 or even lower, depending strongly on the integral neutron flux received by the material. As an ultra-sensitive technique, accelerator mass spectrometry (AMS) is the best for measuring ultratrace 237Np. By extracting negative molecular ions NpO– from the oxide sample using 238UO– and 208Pb16O2– pilot beams for the simulation of 237Np ion transport, identifying the interference isotopes by high-resolution dedicated injector, electrostatic analyzer, and time of flight (TOF) detector, a method for AMS measurement of 237Np was set up on the HI-13 accelerator at the China Institute of Atomic Energy (CIAE). A sensitivity of <10–11 has been achieved for the isotopic ratio 237Np/238U.
Associations of folic acid supplementation with risk of preterm birth (PTB) and small-for-gestational-age (SGA) birth were unclear for the Chinese populations. The aim of the present study was to investigate the associations in a large Chinese prospective cohort study: the Jiaxing Birth Cohort. In the Jiaxing Birth Cohort, 240 954 pregnant women visited local clinics or hospitals within their first trimester in Southeast China during 1999–2012. Information on anthropometric parameters, folic acid supplementation and other maternal characteristics were collected by in-person interviews during their first visit. Pregnancy outcomes were recorded during the follow-up of these participants. Multinomial logistic regression was used to examine the association of folic acid supplementation with pregnancy outcomes. The prevalence of folic acid supplementation was 24·9 % in the cohort. The prevalence of PTB and SGA birth was 3·48 and 9·2 %, respectively. Pre-conceptional folic acid supplementation was associated with 8 % lower risk of PTB (relative risk (RR) 0·92; 95 % CI 0·85, 1·00; P=0·04) and 19 % lower risk of SGA birth (RR 0·81; 95 % CI 0·70, 0·95; P=0·008), compared with non-users. Higher frequency of pre-conceptional folic acid use was associated with lower risk of PTB (Ptrend=0·032) and SGA birth (Ptrend=0·046). No significant association between post-conceptional initiation of folic acid supplementation and either outcome was observed. In conclusion, the present study suggests an association between pre-conceptional, but not post-conceptional, folic acid supplementation and lower risk of PTB and SGA birth in the Jiaxing Birth Cohort. Further research in other cohorts of large sample size is needed to replicate these findings.
The effects of earthquakes on ischemic heart disease (IHD) have often been reported. At a population level, this study examined short-term (60-day) and long-term (5-year) hospitalization events for IHD after the 2008 Sichuan earthquake.
We examined the 10-year medical hospitalization records on IHD in the city of Deyang provided by the Urban Employee Basic Health Insurance program.
Evaluation of 19,083 hospitalizations showed a significantly lower proportional number and cost of hospitalizations in the 60 days after the earthquake (P<0.001). Hospitalizations were 27.81% lower than would have been expected in a normal year; costs were 32.53% lower. However, in the 5 years after the earthquake, the age-adjusted annual incidence of hospitalization increased significantly (P<0.001). In the fifth year after the earthquake, it was significantly higher in the extremely hard-hit area than in the hard-hit area (P<0.01).
After the 2008 earthquake, short- and long-term patterns of hospitalization for IHD changed greatly, but in different ways. Our findings suggest that medical resources for IHD should be distributed dynamically over time after an earthquake. (Disaster Med Public Health Preparedness. 2016;10:203–210)
To assess the association between maternal caffeine intake and risk of pregnancy loss using a systematic review and meta-analysis.
Categorical and dose–response meta-analysis of prospective studies.
Relevant articles were identified by searching MEDLINE and SCOPUS databases through 30 January 2015. Two authors independently extracted information from eligible studies. Random-effects models were used to derive the summary relative risks (RR) and corresponding 95 % CI for specific categories of caffeine consumption and for a continuous association using generalized least-squares trend estimation.
A total of 130 456 participants and 3429 cases in fourteen included studies.
Compared with the reference category with no or very low caffeine intake, the RR (95 % CI) of pregnancy loss was 1·02 (0·85, 1·24; I2=28·3 %) for low intake (50–149 mg/d), 1·16 (0·94, 1·41; I2=49·6 %) for moderate intake (150–349 mg/d), 1·40 (1·16, 1·68; I2=18·6 %) for high intake (350–699 mg/d) and 1·72 (1·40, 2·13; I2=0·0 %) for very high intake (≥700 mg/d). In the dose–response analysis, each 100 mg/d increment in maternal caffeine intake (~1 cup of coffee) was associated with 7 % (95 % CI 3 %, 12 %) higher risk of pregnancy loss. Our results may have been affected by publication bias, but the association remained significant for the subset of larger studies. Furthermore, adjustment for smoking and pregnancy symptoms may have been incomplete, potentially resulting in residual confounding.
Albeit inconclusive, higher maternal caffeine intake was associated with a higher risk of pregnancy loss and adherence to guidelines to avoid high caffeine intake during pregnancy appears prudent.
Hepatitis G virus or GB virus C (GBV-C) is a human virus of the Flaviviridae family that is structurally and epidemiologically closest to hepatitis C virus, but replicates primarily in lymphocytes. Co-infection with GBV-C has been reported to confer beneficial outcomes in some HIV-positive patients. Up to now, however, studies on GBV-C infection in the central nervous system (CNS) of HIV-infected patient have rarely been reported. Herein, we report on a 32-year-old HIV-1-infected patient with cerebral toxoplasmosis and fungal encephalitis. GBV-C viral loads were detected in CSF by quantitative real-time reverse transcription polymerase chain reaction (RT–PCR), and the results showed that GBV-C viral load was 6·5 log copies/ml. We amplified and sequenced the E2 and 5′-untranslated regions from the purified viral RNA from CSF by RT–PCR. Both sequences belong to genotype 3 and there were some minor nucleotide divergence among the E2 sequences from the CSF of the patient. These data suggest that GBV-C may be able to penetrate the blood–brain barrier and colonize the CNS of HIV-infected patients. However, the exact mechanisms and potential effect of the infected GBV-C in CNS on HIV-associated neuropathy needs to be further explored.