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The outbreak of novel coronavirus (COVID-19) provided an opportunity to undertake an online survey to study the relationships between body weight changes with changes in physical activity and lifestyle during an unusual event of forced isolation, or quarantine.
We distributed an electronic questionnaire using the popular social application WeChat to adults from any province of China except Hubei Province, the epicenter of the outbreak. The questionnaire asked for demographic information, body weight, physical activity, and lifestyle factors before and during the quarantine.
Of 376 questionnaires returned, 339 were valid (90.2%). During the period of semi-lockdown, both females and males with BMI <24 gained weight, males with BMI ≥24 lost weight, and females with BMI ≥24 gained weight. The average steps per day and the average moderate or vigorous-intensity exercise declined significantly for both males and females during the semi-lockdown. Changes in body weight inversely correlated with changes in steps per day and moderate or vigorous-intensity exercise during the quarantine.
Normal weight individuals, who are not normally troubled by overweight or obesity, had less awareness of weight gain than people with a BMI ≥ 24. Under the conditions of the semi-lockdown, they tended to gain weight.
Since Deng Xiaoping’s economic reforms starting in 1978, the Chinese government has continuously improved the basic laws and regulations that guarantee women’s economic rights and employment rights. Chinese women can participate equally in economic development, and enjoy the fruits of reform and development on an equal footing with men. In China (Aaltio and Huang, 2007), working women now account for 47.0% of the total labor force, higher than the world average of 40.8%. However, in the computing industry, the proportion of female practitioners in China is about 7% (Proginn and Juejin, 2017; Proginn, 2018), significantly lower than 17% in United States (Elizabeth, 2017). The problem of the small proportion of Chinese computing female practitioners should be remedied.
An in-house self-held respiration monitoring device (SHRMD) was developed for providing deep inspiration breath hold (DIBH) radiotherapy. The use of SHRMD is evaluated in terms of reproducibility, stability and heart dose reduction.
Methods and materials:
Sixteen patients receiving radiotherapy of left breast cancer were planned for treatment with both a free breathing (FB) scan and a DIBH scan. Both FB and DIBH plans were generated for comparison of the heart, left anterior descending (LAD) artery and lung dose. All patients received their treatments with DIBH using SHRMD. Megavoltage cine images were acquired during treatments for evaluating the reproducibility and stability of treatment position using SHRMD.
Compared with FB plans, the maximum dose to the heart by DIBH technique with SHRMD was reduced by 29·9 ± 15·6%; and the maximum dose of the LAD artery was reduced by 41·6 ± 18·3%. The inter-fractional overall mean error was 0·01 cm and the intra-fractional overall mean error was 0·04 cm.
This study demonstrated the potential benefits of using the SHRMD for DIBH to reduce the heart and LAD dose. The patients were able to perform stable and reproducible DIBHs.
We assessed inheritance of resistance to sugarcane brown rust (Puccinia melanocephala) in selfing F1 populations of wild sugarcane germplasm Erianthus rockii ‘Yundian 95-19’ and E. rockii ‘Yundian 95-20’. We tested parent and selfing F1 individuals for the brown rust resistance gene, Bru1, that has been shown to confer resistance to brown rust in sugarcane. The Bru1 gene was not detected in E. rockii ‘Yundian 95-19’, E. rockii ‘Yundian 95-20’ or their selfing F1 individuals, and we found there was segregation of resistance in the two selfing F1 populations (segregation ratio: 3:1). The results confirmed resistance in E. rockii ‘Yundian 95-19’ and E. rockii ‘Yundian 95-20’ to sugarcane brown rust is controlled by a novel, single dominant gene.
This paper presents new LA-ICP-MS zircon U–Pb chronology, whole-rock geochemical and zircon Hf isotopic data for the felsic lavas of the Huili Group from the southwestern Yangtze Block. LA-ICP-MS zircon U–Pb dating shows that these rocks were emplaced in Late Mesoproterozoic time (∼1028 to 1019 Ma). Relative to typical I-type and S-type granitoids, all the samples are characterized by low Sr and Eu, and high high-field-strength element contents, high TFeO/MgO, enriched rare earth element compositions and negative Eu anomalies, indicating that they share the geochemical signatures of A-type granitoid. They can be further divided into two groups: Group I and Group II. Group I are A1-type felsic rocks and were produced by fractional crystallization of alkaline basaltic magmas. The Group II felsic lavas belong to the A2-type and were derived by partial melting of a crustal source with mixing of mantle-derived magmas. Both Group I and Group II felsic lavas may erupt in a continental back-arc setting. The coexistence of A1- and A2-type rocks in the southwestern Yangtze Block suggests that they can occur in the same tectonic setting.
The present study was undertaken to investigate the antiparasitic activity of extracellular products of Streptomyces albus. Bioactivity-guided isolation of chloroform extracts affording a compound showing potent activity. The structure of the compound was elucidated as salinomycin (SAL) by EI-MS, 1H NMR and 13C NMR. In vitro test showed that SAL has potent anti-parasitic efficacy against theronts of Ichthyophthirius multifiliis with 10 min, 1, 2, 3 and 4 h (effective concentration) EC50 (95% confidence intervals) of 2.12 (2.22–2.02), 1.93 (1.98–1.88), 1.42 (1.47–1.37), 1.35 (1.41–1.31) and 1.11 (1.21–1.01) mg L−1. In vitro antiparasitic assays revealed that SAL could be 100% effective against I. multifiliis encysted tomonts at a concentration of 8.0 mg L−1. In vivo test demonstrated that the number of I. multifiliis trophonts on Erythroculter ilishaeformis treated with SAL was markedly lower than that of control group at 10 days after exposed to theronts (P < 0.05). In the control group, 80% mortality was observed owing to heavy I. multifiliis infection at 10 days. On the other hand, only 30.0% mortality was recorded in the group treated with 8.0 mg L−1 SAL. The median lethal dose (LD50) of SAL for E. ilishaeformis was 32.9 mg L−1.
Dietary energy density (ED) might have influences on body composition. We therefore examined whether ED is associated with body composition among Chinese adults.
We collected dietary data through validated two-day 24 h recalls. ED, defined as the amount of energy per unit weight of food consumed, was calculated based on five methods. Multiple linear regression analyses were performed to explore the associations between ED and body composition parameters, including BMI, fat mass index (FMI), fat-free mass index (FFMI), percentage body fat (%BF) and waist circumference (WC).
Chinese adults (n 1933) in 2013.
After adjusting the covariates, all ED definitions were positively associated with BMI, FMI, FFMI, %BF and WC among women (P<0·01). In men, however, ED with foods only was positively associated with BMI, FMI, FFMI and %BF (P<0·05), but not with WC (P=0·07); we also found null associations between ED with foods and all beverages and body composition among men. Additionally, ED contributed to higher increases of body composition in women than in men (P<0·01).
The present study supports the positive association between ED and body composition among adults in Southwest China, in which beverages may play an important role.
In this paper, we introduce a lower extremity exoskeleton CUHK-EXO that is developed to help paraplegic patients, who have lost the motor and sensory functions of their lower limbs to perform basic daily life motions. Since the sit-to-stand and stand-to-sit (STS) motion is the first step for paraplegic patients toward walking, analysis of the exoskeleton's applicability to the STS motion assistance is performed. First, the human-exoskeleton system (HES) is modeled as a five-link model during the STS motion, and the center of pressure (COP) on the ground and center of gravity of the whole system are calculated. Then, a description of the CUHK-EXO hardware design is presented, including the mechatronics design and actuator selection. The COP position is an important factor indicating system balance and wearer's comfort. Based on the COP position, a trajectory online modification algorithm (TOMA) is proposed for CUHK-EXO to counteract disturbances, stabilize system balance, and improve the wearer's comfort in the STS motion. The results of STS motion tests conducted with a paraplegic patient demonstrate that CUHK-EXO can provide a normal reference pattern and proper assistive torque to support the patient's STS motion. In addition, a pilot study is conducted with a healthy subject to verify the effectiveness of the proposed TOMA under external disturbances before future clinical trials. The testing results verify that CUHK-EXO can counteract disturbances, and help the wearer perform the STS motion safely and comfortably.
135Cs with a half-life of T1/2=2.3×106 yr is an important nuclide in studies of the dispersal of nuclear material in the environment. Preliminary measurements using 133Cs as a proxy for the long-lived 135Cs, with accelerator mass spectrometry (AMS) have been developed at the China Institute of Atomic Energy (CIAE). In order to improve the sensitivity of 135Cs AMS measurement, a new conducting material, Fe powder, was used in the experiment. According to the present results, the background level that can be obtained with blanks was 135Ba/Cs~1.83×10–10 with the CIAE-AMS system. These measurements showed that the Fe was an inferior conducting medium because the interference of 135Ba in Fe powder is 10 times higher than that in Ag powder.
Light microscope and scanning electron microscope observations on new material of unicellular microfossils Dictyosphaera macroreticulata and Shuiyousphaeridium macroreticulatum, from the Mesoproterozoic Ruyang Group in China, provide insights into the microorganisms’ biological affinity, life cycle and cellular complexity. Gigantosphaeridium fibratum n. gen. et sp., is described and is one of the largest Mesoproterozoic microfossils recorded. Phenotypic characters of vesicle ornamentation and excystment structures, properties of resistance and cell wall structure in Dictyosphaera and Shuiyousphaeridium are all diagnostic of microalgal cysts. The wide size ranges of the various morphotypes indicate growth phases compatible with the development of reproductive cysts. Conspecific biologically, each morphotype represents an asexual (resting cyst) or sexual (zygotic cyst) stage in the life cycle, respectively. We reconstruct this hypothetical life cycle and infer that the organism demonstrates a reproductive strategy of alternation of heteromorphic generations. Similarly in Gigantosphaeridium, a metabolically expensive vesicle with processes suggests its protective role as a zygotic cyst. In combination with all these characters and from the resemblance to extant green algae, we propose the placement of these ancient microorganisms in the stem group of Chloroplastida (Viridiplantae). A cell wall composed of primary and secondary layers in Dictyosphaera and Shuiyouisphaeridium required a high cellular complexity for their synthesis and the presence of an endomembrane system and the Golgi apparatus. The plastid was also present, accepting the organism was photosynthetic. The biota reveals a high degree of morphological and cell structural complexity, and provides an insight into ongoing eukaryotic evolution and the development of complex life cycles with sexual reproduction by 1200 Ma.
Ketoacids (KA) are known to improve muscle mass among patients with chronic kidney disease (CKD) on a low-protein diet (CKD-LPD), but the mechanism of its preventive effects on muscle atrophy still remains unclear. Since muscle atrophy in CKD may be attributable to the down-regulation of the Wnt7a/Akt/p70S6K pathway and the activation of the ubiquitin–proteasome system (UPS) and the apoptotic signalling pathway, a hypothesis can readily be drawn that KA supplementation improves muscle mass by up-regulating the Wnt7a/Akt/p70S6K pathway and counteracting the activation of the UPS and caspase-3-dependent apoptosis in the muscle of CKD-LPD rats. Rats with 5/6 nephrectomy were randomly divided into three groups, and fed with either 22 % protein (normal-protein diet; NPD), 6 % protein (LPD) or 5 % protein plus 1 % KA for 24 weeks. Sham-operated rats with NPD intake were used as the control. The results demonstrated that KA supplementation improved protein synthesis and increased related mediators such as Wnt7a, phosphorylated Akt and p70S6K in the muscle of CKD-LPD rats. It also inhibited protein degradation, withheld the increase in ubiquitin and its ligases MAFbx (muscle atrophy F-box) and MuRF1 (muscle ring finger-1) as well as attenuated proteasome activity in the muscle of CKD-LPD rats. Moreover, KA supplementation gave rise to a reduction in DNA fragment, cleaved caspase-3 and 14 kDa actin fragment via the down-regulation of the Bax:Bcl-2 ratio in the muscle of CKD-LPD rats. The beneficial effects unveiled herein further consolidate that KA may be a better therapeutic strategy for muscle atrophy in CKD-LPD.
In this paper, we study the regularity of a weak solution for a coupled system derived from a microwave-heating model. The main feature of this model is that electric conductivity in the electromagnetic field is assumed to be temperature dependent. It is shown that the weak solution of the coupled system possesses some regularity under certain conditions. In particular, it is shown that the temperature is Hölder continuous, even if electric conductivity has a jump discontinuity with respect to the temperature change. The main idea in the proof is based on an estimate for a linear degenerate system in Campanato space. As an application, the regularity result for the coupled system is used to derive the necessary condition for an optimal control problem arising in microwave heating processes.
Introduction: Earthquake exposure has been associated with adverse consequences for coronary heart disease. However, the natural history and prognostic significance of earthquake-related, new-onset angina have not been characterized.
Objective: The objective of this study was to evaluate the association between episodes of depressive symptoms and one-year prognosis after the first admission to the hospital among adults with new-onset angina before and after the Sichuan earthquake.
Methods: One hundred forty-one first hospitalized patients with new-onset angina before and after the Sichuan earthquake underwent psychological assessments during their first admission to the hospital following the earthquake. Patients were followed for 12 months to determine survival status. The independent relationships between baseline variables and readmission risk after the earthquake were examined. Baseline somatic and psychosocial variables were collected with the aid of standard, validated questionnaires.
Results: The proportion of patients with moderate/severe depression symptom in the earthquake-related group is higher than among their counterparts (23.7% vs. 8.9%, p = 0.026). Patients with new-onset angina after the Sichuan earthquake had a higher risk of readmission (22.4% vs. 8.9%, p = 0.041) and longer total hospitalization (average of 13.4 ±6.8 vs. 10.7 ±5.5 days, p = 0.015). The risks for readmission was associated with moderate/severe depression (adjusted hazard ratio, 9.18 [95% confidence interval (CI) = 3.09–27.23, p = 0.0000]) and low ejection fraction (adjusted hazard ratio, 6.66 [95%CI = 2.131–20.781, p = 0.001]).
Conclusions: Among patients diagnosed with new-onset angina, those with first episode after the Sichuan earthquake generated more moderate/severe depressive symptoms and had a higher risk for readmission and longer hospital stay. Depressive symptoms upon admission and low ejection fractions were significant predictors of 12-month risk for readmission, which indicates that antidepressants should be prescribed.
The Linkuo terrace, situated to the west of the Taipei Basin in NW Taiwan, has thick red soils that have been little studied. This paper aims to interpret the development of these soils through chemical and micromorphological investigations, and relate the soils to their palaeo-environments. The soil samples were air dried, crushed and passed through a 2 mm sieve, and then subjected to conventional soil chemical and physical analyses, together with clay mineralogical and morphological characterization. Pedons I and II were clay with low base saturation (BS), cation-exchange capacity (CEC), and exchangeable cations. The pH of pedons I and II ranged from 3.80 to 5.26. The low magnetic susceptibility of these soils indicates that no magnetite (Fe3O4) or maghemite (γ-Fe2O3) are present. X-ray diffraction patterns of the magnetic clay fraction showed lepidocrocite, goethite and hematite, the amounts of which may relate to water fluctuation in the soil environments. Illite, kaolinite and quartz are major clay minerals in the red soil clay fractions. The micromorphology of all horizons showed a great accumulation of Fe-oxides. The upper horizon showed darkened isotropic Fe-oxide materials, and lower horizon showed a black to reddish dense plasma with soil matrix. The groundmass of the oxic horizon is generally characterized by a homogeneous distribution of the different coarse and fine constituents. The thick (4 m depth) and homogeneous red soils of the Linkuo terrace were developed from fine sediments after the gradual subsidence of the Taipei Basin. Alarge amount of gravel was flushed from the Xindian River before the Taipei Basin subsided. The Linkuo red soils can be classified as mesic, Typic Kandiudox. From the chemical compositions of clay fractions and the red soil features, these red soils can be considered as lateritic red earths or red earths that do not reach the criteria for laterite.
A kind of novel poly-L-lactide (PLLA)/β-calcium metaphosphate (β-CMP) fracture-fixation composite rod was prepared by a two-step compression-molding method. The in vitro bioactivity of the composite rod was evaluated by investigating the effects of dissolved products from the composite rod on osteoblasts. In addition, the in vitro biocompatibility of the composite rod was evaluated by an osteoblast adhesion-and-proliferation assay. The products from composite rod dissolution significantly promoted cell growth. Furthermore, osteoblasts adhered and spread well on the rod. This PLLA/β-CMP composite rod has potential applications for clinical use following the assessment of adaptation during in vivo studies.
Monodisperse ligand-capped cubic wüstite FexO nanocrystals were prepared by a novel thermal decomposition method of iron (II) acetate in the presence of oleic acid as the surfactant. Controlled size distributions of cubic nanoparticles possessing the rock salt crystal structure were isolated in the range 10–18 nm. The influence of molar ratio of surfactant to precursor was investigated to understand size control and monodispersity. Using inexpensive, nontoxic metal salts as reactants, we were able to synthesize gram-scale quantities of relatively monodisperse nanocrystals in a single reaction, without further size selection, characterized by x-ray diffraction and transmission electron microscopy. The procedure enables the collection of samples of uniform size as a function of time, thus permitting a preliminary solid-state kinetic analysis of the reaction as a function of increasing particle size. Following controlled evaporation from nonpolar solvents, self-assembly into two-dimensional arrays, three-dimensional single-component superlattices, and binary superlattices with gold nanoparticles were observed and characterized.
In order to investigate the molecular mechanism of rehydration after serious drought in broomcorn millet (Panicum miliaceum L.), a forward subtracted cDNA library was constructed between normal watered leaves and rehydrated leaves after serious drought conditions, using the suppressive subtraction hybridization (SSH) technique. A total of 60 positive clones were picked out at random from the subtracted library and sequenced, and redundancy sequences were removed after sequence alignment. Based on the results of sequence homologous comparison and function querying, 32 expressed sequence tags (EST) were highly homologous with known ESTs. Most of those sequences were related to either abiotic or biotic stress in plants. Of those sequences, 11 ESTs were homologous with ESTs in rat (Rattus norvegicus) liver after partial hepatectomy. The Blast result of proteins revealed that 28 ESTs were similar to known proteins. The functions of these proteins mainly involve signal transduction, transcription and protein processing. This experiment demonstrated that a range of specific genes was induced and expressed in broomcorn millet during the rehydration stage after serious drought.
With the development of plant genetic engineering, many transformation methods can be used to transfer heterogeneous genes into plants to develop genetic crops. However, a lot of research results have shown that transgene expression remains largely unpredictable and there is great variation of expression level in different transgenic plant lines. Plant genetic engineering research is reviewed in the present paper. We analysed the reasons why low efficiency of heterogeneous gene expression has happened in transgenic plants in terms of DNA modification, localization of proteins and methods of transformation used. Some strategies for improving heterogeneous gene expression in transgenic plants are also discussed.