The cross sections of e^{+}e^{-}→π^{+}π^{-}h_{c} at center-of-mass energies from 3.896 to 4.600 GeV are measured using data samples collected with the BESIII detector operating at the Beijing ...Electron Positron Collider. The cross sections are found to be of the same order of magnitude as those of e^{+}e^{-}→π^{+}π^{-}J/ψ and e^{+}e^{-}→π^{+}π^{-}ψ(2S), but the line shape is inconsistent with the Y states observed in the latter two modes. Two structures are observed in the e^{+}e^{-}→π^{+}π^{-}h_{c} cross sections around 4.22 and 4.39 GeV/c^{2}, which we call Y(4220) and Y(4390), respectively. A fit with a coherent sum of two Breit-Wigner functions results in a mass of (4218.4_{-4.5}^{+5.5}±0.9) MeV/c^{2} and a width of (66.0_{-8.3}^{+12.3}±0.4) MeV for the Y(4220), and a mass of (4391.5_{-6.8}^{+6.3}±1.0) MeV/c^{2} and a width of (139.5_{-20.6}^{+16.2}±0.6) MeV for the Y(4390), where the first uncertainties are statistical and the second ones systematic. The statistical significance of Y(4220) and Y(4390) is 10σ over one structure assumption.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Global petroleum exploration is currently undergoing a strategic shift from conventional to unconventional hydrocarbon resources. Unconventional hydrocarbons in tight reservoirs show characteristics ...distinct from those of conventional hydrocarbon sources hosted in structural and stratigraphic traps. The characteristic features include the following: a hydrocarbon source and reservoir coexist; porosity and permeability are ultra-low; nano-pore throats are widely distributed; hydrocarbon-bearing reservoir bodies are continuously distributed; there is no obvious trap boundary; buoyancy and hydrodynamics have only a minor effect, and Darcy's law does not apply; phase separation is poor; there is no uniform oil–gas–water interface or pressure system; and oil or gas saturation varies. Examples of unconventional hydrocarbon accumulations are the Mesozoic tight sandstone oil province and the Upper Paleozoic tight sandstone gas province in the Ordos Basin, north-central China. Generally, continuous hydrocarbon accumulation over a large area is a distinguishing characteristic of unconventional hydrocarbon sources. Because of the great potential of unconventional petroleum resources, it is believed that research on such resources will be at the forefront of the future development of petroleum geology.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Hydrolysis of sodium borohydride (NaBH sub(4)) is one of the most attractive methods for energy generation of mobile systems used as hydrogen source because of the high gravimetric density and ...controllable hydrogen generation of NaBH sub(4). However, regeneration of NaBH sub(4) is a key issue that remains to be solved, and the energy efficiency of NaBH sub(4) is unknown. In the present study, the energy efficiency of NaBH sub(4) hydrolysis and the entire process of sodium metaborate (NaBO sub(2)) regeneration via reaction with magnesium hydride (MgH sub(2)) is determined through thermodynamics calculations. The maximum energy efficiency is 49.91%, indicating that NaBH sub(4) generation by reaction between MgH sub(2) and NaBO sub(2) during ball milling is feasible. An inexpensive high-energy ball milling method is employed to regenerate NaBH sub(4) by reaction of NaBO sub(2) with magnesium-lanthanum hydrides (H-Mg sub(3)La). Products after ball milling are characterized through Fourier transform infrared spectroscopy and X-ray diffraction measurements. In the reaction of NaBO sub(2) with H-Mg sub(3)La, MgH sub(2) reacts with NaBO sub(2) and then lanthanum hydride (LaH sub(3)) reacts with NaBO sub(2) to produce NaBH sub(4).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
To reveal the association between retinal microvasculature changes and coronary heart disease (CHD), we assessed the full retinal thicknesses of eight areas, the vessel density of four layers ...(consisting of nine areas) and the flow area in two layers with optical coherence tomography angiography (OCTA) in CHD patients and healthy controls. The mean vessel density of several layers was significantly lower in patients. The difference in choroid capillary flow (negative correlation) between the two groups was significant. Decreased vessel density and blood flow were associated with coronary artery and branch stenosis. The decreases in retinal vessel density, choroidal vessel density, and blood flow area are closely related to coronary artery and branch stenosis.
The aim of this study was to explore the allelic association between SOST polymorphisms and the variance of clinical effects of alendronate in postmenopausal Chinese women with osteoporosis or ...osteopenia. In the study, 500 postmenopausal women in Shanghai area with osteoporosis or osteopenia were included. All participants were treated with weekly oral alendronate 70 mg, daily calcium 600 mg and vitamin D 125 IU for 12 months. Nine tagging single-nucleotide polymorphisms (SNPs) in SOST gene were genotyped. Bone mineral density of lumbar spine (L1-L4), left femoral neck and total hip were measured at baseline and after 1 year of treatment, respectively. In the study, 450 subjects completed the 1-year follow-up. The rs865429 was significantly associated with the % change of BMD at the femoral neck (P = 0.007). GG carriers seemed to be at an advantage after treatment of alendronate. Compared with AG and AA heterozygote, GG homozygote had the highest % change of BMD (3.100 ± 2.899%) at femoral neck. The odds ratio (95% confidence) of GG homozygote to be responders at femoral neck was 1.921 (1.211-3.048). Two haplotypes GG and AC constituted by rs865429 and rs851057 were associated with the % change of BMD at femoral neck and total hip, respectively. Therefore, the common variation of SOST gene contribute to the therapeutic response to alendronate treatment in Chinese women with osteoporosis or osteopenia.
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EMUNI, GIS, NUK, SBMB, SBNM, UL, UM, UPUK
This study aims to assess the risk factors of cardiovascular disease (CVD) and to determine the association of traditional and biologic disease-modifying anti-rheumatic drugs (DMARDs) with risk for ...CVD in Chinese rheumatoid arthritis (RA) patients. A cross-sectional cohort of 2013 RA patients from 21 hospitals around China was established. Medical history of CVD was documented. The patients’ social background, clinical manifestations, comorbidities, and medications were also collected. Of the 2013 patients, 256 had CVD with an incidence of 12.7%. Compared with non-CVD controls, RA patients with CVD had a significantly advanced age, long-standing median disease duration, more often male and more deformity joints. Patients with CVD also had higher rates of smoking, rheumatoid nodules, interstitial lung disease, and anemia. The prevalence of comorbidities, including hypothyroidism, diabetes mellitus (DM), hypertension, and hyperlipidemia, was also significant higher in the CVD group. In contrast, patients treated with methotrexate, hydroxychloroquine (HCQ), and TNF blockers had lower incidence of CVD. The multivariate analysis showed that the use of HCQ was a protective factor of CVD, while hypertension, hyperlipidemia, and interstitial lung disease were independent risk factors of CVD. Our study shows that the independent risk factors of CVD include hypertension, hyperlipidemia, and interstitial lung disease. HCQ reduces the risk of CVD in patients with RA.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The spin and parity of the Z_{c}(3900)^{±} state are determined to be J^{P}=1^{+} with a statistical significance larger than 7σ over other quantum numbers in a partial wave analysis of the process ...e^{+}e^{-}→π^{+}π^{-}J/ψ. We use a data sample of 1.92 fb^{-1} accumulated at sqrts=4.23 and 4.26 GeV with the BESIII experiment. When parametrizing the Z_{c}(3900)^{±} with a Flatté-like formula, we determine its pole mass M_{pole}=(3881.2±4.2_{stat}±52.7_{syst}) MeV/c^{2} and pole width Γ_{pole}=(51.8±4.6_{stat}±36.0_{syst}) MeV. We also measure cross sections for the process e^{+}e^{-}→Z_{c}(3900)^{+}π^{-}+c.c.→J/ψπ^{+}π^{-} and determine an upper limit at the 90% confidence level for the process e^{+}e^{-}→Z_{c}(4020)^{+}π^{-}+c.c.→J/ψπ^{+}π^{-}.
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The short-range ordered but long-range disordered structure of metallic glasses yields strong structural and dynamic heterogeneities. Stress relaxation is a technique to trace the evolution of stress ...in response to a fixed strain, which reflects the dynamic features phenomenologically described by the Kohlrausch-Williams-Watts (KWW) equation. The KWW equation describes a broad distribution of relaxation times with a small number of empirical parameters, but it does not arise from a particular physically motivated mechanistic picture. Here we report an anomalous two-stage stress relaxation behavior in a Cu sub(46) Zr sub(46) Al sub(8) metallic glass over a wide temperature range and generalize the findings in other compositions. Thermodynamic analysis identifies two categories of processes: a fast stress-driven event with large activation volume and a slow thermally activated event with small activation volume, which synthetically dominates the stress relaxation dynamics. Discrete analyses rationalize the transition mechanism induced by stress and explain the anomalous variation of the KWW characteristic time with temperature. Atomistic simulations reveal that the stress-driven event involves virtually instantaneous short-range atomic rearrangement, while the thermally activated event is the percolation of the fast event accommodated by the long-range atomic diffusion. The insights may clarify the underlying physical mechanisms behind the phenomenological description and shed light on correlating the hierarchical dynamics and structural heterogeneity of amorphous solids.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
The physical and chemical properties of nanophase materials rely on their crystal and surface structures. Transmission electron microscopy (TEM) is a powerful and unique technique for structure ...characterization. The most important application of TEM is the atomic-resolution real-space imaging of nanoparticles. This article introduces the fundamentals of TEM and its applications in structural determination of shape-controlled nanocrystals and their assemblies. By forming a nanometer size electron probe, TEM is unique in identifying and quantifying the chemical and electronic structure of individual nanocrystals. Electron energy-loss spectroscopy analysis of the solid-state effects and mapping the valence states are even more attractive. In situ TEM is demonstrated for characterizing and measuring the thermodynamic, electric, and mechanical properties of individual nanostructures, from which the structure−property relationship can be registered with a specific nanoparticle/structure.
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IJS, KILJ, NUK, PNG, UL, UM
In China, ethnic minorities often live in frontier areas and have a relatively small population size, and tremendous social transitions have enlarged the gap between eastern and western China, with ...western China being home to 44 ethnic minority groups. These three disadvantages have health impacts. Examining ethnicity and health inequality in the context of western China is therefore essential.
This paper is based on data from the 2010 China Survey of Social Change (CSSC2010), which was conducted in 12 provinces, autonomous regions and province-level municipalities in western China and had a sample size of 10,819. We examined self-rated health and disparities in self-rated health between ethnic minorities and Han Chinese in the context of western China. Self-rated health was coded as poor or good, and ethnicity was coded as ethnic minority or Han Chinese. Ethnic differences in self-rated health was examined by using binary logistic regression. Associations among sociodemographic variables, SES variable, health behaviour variable, health problem variables and self-rated health were also explored.
Fourteen percent of respondents reported their health to be poor. A total of 15.75% of ethnic minorities and 13.43% of Han Chinese respondents reported their health to be poor, indicating a difference in self-rated health between ethnic minorities and Han Chinese. Age, gender, marital status, education, alcohol, and health problems were the main factors that affected differences in self-rated health.
In western China, there were obvious ethnic disparities in self-rated health. Elderly ethnic minorities, non-partnered ethnic minorities, ethnic minorities with an educational level lower than middle school, and ethnic minorities with chronic disease had higher odds of poor self-rated health.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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