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Continuous hBN films have been grown by means of a radio-frequency-sputtering technology, and their material properties have been investigated. The prepared hBN films can achieve good smoothness in a large area. The surface morphologies and compositions of the hBN films on Si substrate and Al film have been characterized, indicating that there is no difference. The 101-phase peak of hBN film is the strongest, and the optical band gap of the fabricated film is 5.84 eV. An attempt on the fabrication of the hBN based resistive switching (RS) device has been made by using an Ag/hBN/Al structure, leading to the observation of a clear and stable RS behavior. The device exhibits a resistance window (high-resistivity state/low-resistivity state) of around 102, and the RS behaviors of hBN film prepared by sputtering were first observed. It has been found that the opening voltage for the device is changed when a different cycle voltage is applied because of the built-in electric field increasing with the increase of applied cycle voltage. The mechanism of the RS behavior has been analyzed, which lay a foundation for the application of hBN as RS material in resistive random access memory to improve the storage density.
Although the progression of invasive aspergillosis (IA) shares some risk factors in the development of active pulmonary tuberculosis (PTB), however, the prevalence of IA in suspected PTB remains unclear. During a period of 1 year (from January 2016 to December 2016), consecutive patients with suspected PTB were included in a referral TB hospital. Data, including demographic information and underlying diseases, were collected from medical records. PTB were all confirmed by mycobacterial culture (Lowenstein–Jensen medium). IA were diagnosed as proven or probable according to the criteria of the 2008 EORTC/MSG definitions. A descriptive analysis was performed to estimate the corresponding prevalence. During the study year, 1507 patients have a positive mycobacterial culture, with a mean age of 45.6 (s.d. 19.9) years old and a female:male ratio of 1:4. Among the 82 patients with non-tuberculous mycobacterial diseases, two patients (2.44%, 95% CI 0.67–8.46%) were diagnosed as IA (one proven and one probable); two probable IA patients (0.15%, 95% CI 0.04–0.55%) were diagnosed in PTB patients (n = 1315), and all were retreatment cases. In addition, all four IA patients (100%) exhibited cavities in both lobes on radiograph. In China, the prevalence of IA is low in active PTB patients. However, when high-risk factors for IA are encountered in PTB patients, further investigations are required and empirically treatment for IA might be warranted.
Acute haemorrhagic conjunctivitis is a highly contagious eye disease, the prediction of acute haemorrhagic conjunctivitis is very important to prevent and grasp its development trend. We use the exponential smoothing model and the seasonal autoregressive integrated moving average (SARIMA) model to analyse and predict. The monthly incidence data from 2004 to 2017 were used to fit two models, the actual incidence of acute haemorrhagic conjunctivitis in 2018 was used to validate the model. Finally, the prediction effect of exponential smoothing is best, the mean square error and the mean absolute percentage error were 0.0152 and 0.1871, respectively. In addition, the incidence of acute haemorrhagic conjunctivitis in Chongqing had a seasonal trend characteristic, with the peak period from June to September each year.
More mobile devices such as mobile phones and robots are wirelessly charged for convenience, simplicity, and safety, and it would be desirable to achieve three-dimensional (3D) wireless charging with high spatial freedom and long range. This paper proposes a 3D wireless charging cube with three orthogonal coils and supporting magnetic cores to enhance the magnetic flux outside the cube. The proposed system is simulated by Ansoft Maxwell and implemented by a downsized prototype. Both simulation and experimental results show that the magnetic cores can strengthen the magnitude of B-field outside the cube. The final prototype demonstrates that the power transfer distance outside the cube for getting the same induced electromotive force in the receiver coil is extended approximately by 50 mm using magnetic cores with a permeability of 2800. It is found that the magnitude of B-field outside the cube can be increased by increasing the width and the permeability of the magnetic cores. The measured results show that when the permeability of the magnetic cores is fixed, the induced electromotive force in the receiver coil at a point 300 mm away from the center of the cube is increased by about 2V when the width of the magnetic cores is increased from 50 to 100 mm. The increase in the induced electromotive force at an extended point implies a greater potential of wireless power transfer capability to the power pickup.
The aim of this retrospective study was to investigate the prognostic significance of pre-treatment immunological and nutritional statuses in patients with locally advanced gastric cancer (GC), and to use the risk factors to develop a predictive score. A total of 731 patients who underwent gastrectomy for stage II/III GC from November 2010 to December 2015 were recruited into this retrospective study. On the basis of univariate and further multivariate Cox regression analyses, decreased pretreatment lymphocyte count (<1·5×109/litre) and prealbumin concentrations (<180 mg/l) were identified to be independently associated with poorer overall survival (OS) and disease-free survival (DFS). Low albumin concentrations (<33 g/l) were identified as an independent risk factor only for OS, but not for DFS. Thereafter, patients who had a decreased prealbumin concentration and lymphocyte count were given a combination of serum prealbumin concentration and lymphocyte count (Co-PaL) score of 2. Patients with only one or neither of these concentrations were given a Co-PaL score of 1 or 0, respectively. Both the OS and the DFS time were inversely related to the Co-PaL scores, and the differences among the three groups were all significant. In contrast, the prognosis did not differ significantly between patients with good nutrition and those with mild to moderate malnutrition according to the prognostic nutritional index. This study indicated that the simple scoring system could accurately predict the prognosis of patients who underwent gastrectomy for stage II/III GC. The score might be helpful in terms of clinical preoperative decision-making.
Power repeaters are used to extend the power transfer range or enhance the power transfer capability of Inductive Power Transfer (IPT) systems, but how to tune the power repeaters to improve the system power transfer performance remains an unsolved problem. In this paper, studies of the effect of the tuning capacitance of the power repeater of an IPT system on the power transfer capability are presented. A theoretical model is established to analyze the output power of the system with the primary coil and secondary coil tuned at a nominal resonant frequency, and a passive power repeater placed in between. By analyzing the relationship between the tuning capacitance of the power repeater and the output power, a critical tuning capacitance which sets up the boundary between enhancing and reducing the output power is determined, and the optimal tuning capacitances corresponding to the maximum and minimum output power are also obtained. A practical IPT system with a passive power repeater placed at 40, 80, and 104 mm from the primary coil is built. It has shown that the practically measured critical capacitance and the optimal tuning capacitance for maximum power transfer are in good agreement with the analytical results.
Disclosing the diagnosis of Alzheimer's disease (AD) to a patient is controversial. There is significant stigma associated with a diagnosis of AD or dementia in China, but the attitude of the society toward disclosure of such a diagnosis had not been formally evaluated prior to our study. Therefore, we aimed to evaluate the attitude toward disclosing an AD diagnosis to patients in China with cognitive impairment from their caregivers, and the factors that may affect their attitude.
We designed a 17-item questionnaire and administered this questionnaire to caregivers, who accompanied patients with cognitive impairment or dementia in three major hospitals in Shanghai, China. The caregiver's attitude toward disclosing the diagnosis of AD as evaluated by the questionnaire was compared to that of disclosing the diagnosis of terminal cancer.
A majority (95.7%) of the 175 interviewed participants (mean 14.2 years of education received) wished to know their own diagnosis if they were diagnosed with AD, and 97.6% preferred the doctor to tell their family members if they were diagnosed with AD. If a family member of the participants suffered from AD, 82.9% preferred to have the diagnosis disclosed to the patient. “Cognitive impairment” was the most accepted term by caregivers to disclose AD diagnosis in Chinese.
This study suggests most of the well-educated individuals in a Chinese urban area favored disclosing the diagnosis when they or their family members were diagnosed with AD.
In tropical plant communities with diverse species, many congeners are found to coexist. Do environment or biotic interactions structure the coexistence of congeners in tropical forest communities? In this paper, we aimed to disentangle the effect of environment (first-order effects) and species interactions (second-order effects) on the spatial distributions of tree species. We used a classification scheme and torus-translation to test the first-order interaction of 48 species from 17 genera in a fully mapped 20-ha dipterocarp tropical seasonal rain-forest plot in Xishuangbanna, south-west China. Then we used heterogeneous Poisson null models to reveal significant uni- and bivariate second-order interactions. The results demonstrated that (1) 34 of the 48 studied species showed a significant relation with at least one topographic variable. This confirmed that topographical heterogeneity is important for distribution of these congeners. Spatial segregation (36.6%) and partial overlap (34.8%) were the most common bivariate association types in Xishuangbanna plot, which indicated first-order effects (environment) were strong. (2) For small-scale associations, 51% saplings (1 to ≤ 5 cm) (68.8% for large trees with dbh > 5 cm) of the species showed non-significant associations. For large-scale associations, 61.6% saplings (81.2% for large trees) of the species showed non-significant associations. Lack of significant species interactions provides evidence for the unified neutral theory. In conclusion, both environment and biotic interactions structure congeneric species' coexistence in tropical seasonal rain forest in this region.
The tin–bismuth eutectic alloy possesses anomalous physicochemical properties that are dependent on temperature. This paper reports the interfacial reaction and growth behavior of the intermetallic compound (IMC) layer during the dissolution of solid copper in liquid eutectic tin–bismuth at 673–823 K under the influence of the structural transition of liquid eutectic tin–bismuth. The structural transition markedly affected the dissolution rate constant of solid copper and the growth rate of the IMCs. Correspondingly, the application of the liquid structural transition significantly decreased the activation energy of dissolution and increased the apparent activation energy for IMC growth. Moreover, two major roles of elemental Bi on the formation and growth of the IMCs were suggested.
Autophagy process in Toxoplasma gondii plays a vital role in regulating parasite survival or death. Thus, once having an understanding of certain effects of autophagy on the transformation of tachyzoite to bradyzoite this will allow us to elucidate the function of autophagy during parasite development. Herein, we used three TgAtg proteins involved in Atg8 conjugation system, TgAtg3, TgAtg7 and TgAtg8 to evaluate the autophagy level in tachyzoite and bradyzoite of Toxoplasma in vitro based on Pru TgAtg7-HA transgenic strains. We showed that both TgAtg3 and TgAtg8 were expressed at a significantly lower level in bradyzoites than in tachyzoites. Importantly, the number of parasites containing fluorescence-labelled TgAtg8 puncta was significantly reduced in bradyzoites than in tachyzoites, suggesting that autophagy is downregulated in Toxoplasma bradyzoite in vitro. Moreover, after treatment with drugs, bradyzoite-specific gene BAG1 levels decreased significantly in rapamycin-treated bradyzoites and increased significantly in 3-MA-treated bradyzoites in comparison with control bradyzoites, indicating that Toxoplasma autophagy is involved in the transformation of tachyzoite to bradyzoite in vitro. Together, it is suggested that autophagy may serve as a potential strategy to regulate the transformation.
Intra-uterine growth restriction (IUGR) impairs postnatal growth and skeletal muscle development in neonatal infants. This study evaluated whether dietary β-hydroxy-β-methylbutyrate Ca (HMB-Ca) supplementation during the early postnatal period could improve muscle growth in IUGR neonates using piglets as a model. A total of twelve pairs of IUGR and normal-birth-weight (NBW) male piglets with average initial weights (1·85 (sem 0·36) and 2·51 (sem 0·39) kg, respectively) were randomly allotted to groups that received milk-based diets (CON) or milk-based diets supplemented with 800 mg/kg HMB-Ca (HMB) during days 7–28 after birth. Blood and longissimus dorsi (LD) samples were collected and analysed for plasma amino acid content, fibre morphology and the expression of genes related to muscle development. The results indicate that, regardless of diet, IUGR piglets had a significantly decreased average daily weight gain (ADG) compared with that of NBW piglets (P<0·05). However, IUGR piglets fed HMB-Ca had a net weight and ADG similar to that of NBW piglets fed the CON diet. Irrespective of body weight (BW), HMB-Ca supplementation markedly increased the type II fibre cross-sectional area and the mRNA expression of mammalian target of rapamycin (mTOR), insulin-like growth factor-1 and myosin heavy-chain isoform IIb in the LD of piglets (P<0·05). Moreover, there was a significant interaction between the effects of BW and HMB on mTOR expression in the LD (P<0·05). In conclusion, HMB-Ca supplementation during the early postnatal period could improve skeletal muscle growth and maturity by accelerating fast-twitch glycolytic fibre development in piglets.
In this study, the effects of Sm on the microstructure and corrosion resistance of hot-extruded AZ61 magnesium alloys were investigated by optical microscopy, scanning electron microscopy, and transmission electron microscopy. The results showed that uniformly dispersed Al2Sm particles with size of ∼2 μm were discovered in the hot-extruded AZ61 magnesium alloy sample modified with 1.0 wt% Sm, which promoted dynamic recrystallization grain growth during the hot-extruded process, gradually increasing the grain of the alloy as Sm content increased. The morphology of the corroded surface and the corrosion rate of the hot-extruded AZ61 magnesium alloy both were significantly improved after Sm addition. The alloy sample modified with 2.0 wt% Sm after immersion in 3.5 wt% NaCl solution for 12 h showed minimum corrosion rate value, 3.1 mg/cm2 day, which is only 3.7% of the corrosion rate of unmodified alloy (82 mg/cm2 day).
The Doba gabbro was collected from an exploration well through the Cretaceous Doba basin of southern Chad. The gabbro is composed mostly of plagioclase, clinopyroxene and Fe–Ti oxide minerals and displays cumulus mineral textures. Whole-rock 40Ar–39Ar step-heating geochronology yielded a Late Permian plateau age of 257 ± 1 Ma. The major and trace elemental geochemistry shows that the gabbro is tholeiitic in composition and has trace element ratios (i.e. La/YbN > 7; Sm/YbPM > 3.4; Nb/Y > 1; Zr/Y > 5) indicative of a basaltic melt derived from a garnet-bearing mantle source. The moderately enriched Sr–Nd isotopes (i.e. ISr = 0.70495 to 0.70839; ɛNd(T) = −1.0 to −1.3) fall within the mantle array (i.e. OIB-like) and are similar to other Late Permian plutonic rocks of North-Central Africa (i.e. ISr = 0.7040 to 0.7070). The enriched isotopic composition of the Doba gabbro contrasts with the more depleted compositions of the spatially associated Neoproterozoic post-Pan-African within-plate granites. The contrasting Nd isotope composition between the older within-plate granites and the younger Doba gabbro indicates that different mantle sources produced the rocks and thus may mark the southern boundary of the Saharan Metacraton.
Few studies have explored the relationship between dietary patterns and the risk of gestational diabetes mellitus (GDM). Evidence from non-Western areas is particularly lacking. In the present study, we aimed to examine the associations between dietary patterns and the risk of GDM in a Chinese population. A total of 3063 pregnant Chinese women from an ongoing prospective cohort study were included. Data on dietary intake were collected using a FFQ at 24–27 weeks of gestation. GDM was diagnosed using a 75 g, 2 h oral glucose tolerance test. Dietary patterns were determined by principal components factor analysis. A log-binomial regression model was used to examine the associations between dietary pattern and the risk of GDM. The analysis identified four dietary patterns: vegetable pattern; protein-rich pattern; prudent pattern; sweets and seafood pattern. Multivariate analysis showed that the highest tertile of the vegetable pattern was associated with a decreased risk of GDM (relative risk (RR) 0·79, 95 % CI 0·64, 0·97), compared with the lowest tertile, whereas the highest tertile of the sweets and seafood pattern was associated with an increased risk of GDM (RR 1·23, 95 % CI 1·02, 1·49). No significant association was found for either the protein-rich or the prudent pattern. The protective effect of a high vegetable pattern score was more evident among women who had a family history of diabetes (P for interaction = 0·022). These findings suggest that the vegetable pattern was associated with a decreased risk of GDM, while the sweets and seafood pattern was associated with an increased risk of GDM. These findings may be useful in dietary counselling during pregnancy.
Numerical simulation based on the Euler equation and one-step reaction model is carried out to investigate the process of deflagration to detonation transition (DDT) occurring in a straight duct. The numerical method used includes a high resolution fifth-order weighted essentially non-oscillatory (WENO) scheme for spatial discretization, coupled with a third order total variation diminishing Runge-Kutta time stepping method. In particular, effect of energy release on the DDT process is studied. The model parameters used are the heat release at q = 50,30,25,20,15,10 and 5, the specific heat ratio at 1.2, and the activation temperature at Ti = 15, respectively. For all the cases, the initial energy in the spark is about the same compared to the detonation energy at the Chapman-Jouguet (CJ) state. It is found from the simulation that the DDT occurrence strongly depends on the magnitude of the energy release. The run-up distance of DDT occurrence decreases with the increase of the energy release for q = 50 ~ 20, and increases with the increase of the energy release for q = 20 ~ 5. This phenomenon is found to be in agreement with the analysis of mathematical stability theory. It is suggested that the factors to strengthen the DDT would make the detonation more stable, and vice versa. Finally, it is concluded from the simulations that the interaction of the shock wave and the flame front is the main reason for leading to DDT.
Monodominance in the tropics is often seen as an unusual phenomenon due to the normally high diversity in tropical rain forests. Here we studied Parashorea chinensis H. Wang (Dipterocarpaceae) in a seasonal tropical forest in south-west China, to elucidate the mechanisms behind its monodominance. Twenty-eight 20 × 20-m plots were established in monodominant and mixed forest in Xishuangbanna, Yunnan province. All individuals ≥1 cm stem diameter and 16 soil variables were measured. Parashorea chinensis forest had a significantly higher mean tree dbh compared with mixed forest. Diversity did not differ significantly between the two forest types. However, within monodominant patches, all diversity indices decreased with an increase in P. chinensis dominance. Floristic composition of P. chinensis forest did differ significantly from the mixed forest. These differences were associated with more fertile soils (significantly higher pH, Mn, K and lower carbon pools and C:N ratio) in the P. chinensis forest than the mixed forest. In contrast to current paradigms, this monodominant species is not associated with infertile, but with fertile soils. Parashorea chinensis seems to be especially associated with high manganese concentrations which it can tolerate, and with edaphic conditions (water, K) that allow this tall and exposed emergent species to maintain its water balance. This is in contrast with most previous studies on monodominance in the tropics that found either no effect of soil properties, or predict associations with nutrient-poor soils.
Depression is a serious mental disorder in the world, but the underlying mechanisms remain unclear and the effective cures are scarce. Iptakalim (Ipt), an ATP-sensitive potassium (K-ATP) channel opener that can cross the blood-brain barrier freely, has been demonstrated to inhibit neuro-inflammation and enhance adult hippocampal neurogenesis. But it is unknown whether Ipt is beneficial to therapy of depression by modulating neurogenesis and neuro-inflammation. This study aimed to determine the potential antidepressant efficacy of Ipt in a chronic mild stress (CMS) mouse model of depression. We showed that treatment with Ipt (10 mg/kg/day, i.p) for 4 wk restored the decrease of sucrose preference and shortened the immobile time in forced swimming tests (FST) and tail suspension tests (TST) in CMS model mice. We further found that Ipt reversed the CMS-induced reduction of the adult hippocampal neurogenesis and improved cerebral insulin signalling in the CMS mice. Furthermore, Ipt negatively regulated nod-like receptor protein 3 (NLRP3) expression and, in turn, inhibited microglia-mediated neuro-inflammation by suppressing the activation of NLRP3-inflammasome/caspase-1/interleukin 1β axis in the hippocampus of CMS mice. Taken together, our findings demonstrate that Ipt plays a potential antidepressant role in CMS model mice through regulating neuro-inflammation and neurogenesis, which will provide potential for Ipt in terms of opening up novel therapeutic avenues for depression.
Morphogenesis and identification of embryonic differentiation in porcine embryos are crucial issues for developmental biology and laboratory animal science. The current paper presents a study on the asynchronous development of hatched porcine embryos from days 7 to 13 post-insemination. Examination of semi-thin sections of the hypoblast showed that it had characteristics similar to those of the mouse anterior visceral endoderm during embryonic disc formation. Also, a cavity appeared in the epiblast, which was similar to a mouse proamniotic cavity. With the gradual disappearance of Rauber's layer, the cavity opened and contacted the external environment directly, all of which formed the embryonic disc. To confirm the differentiation characteristics, we performed immunohistochemical analyses and showed that GATA6 was detected clearly in parietal endoderm cells during embryonic disc establishment. OCT4 was expressed in the inner cell mass (ICM) and trophoblast of hatched blastocysts and in the epiblast during formation of the embryonic disc. However, OCT4 showed comparatively decreased expression in the posterior embryonic disc, primitive streak and migrating cells. SOX2 was present in the ICM and epiblast. Therefore, both SOX2 and OCT4 can be used as markers of pluripotent cells in the porcine embryonic disc. At the start of gastrulation, staining revealed VIMENTIN in the posterior of the embryonic disc, primitive streak and in migrating cells that underlay the embryonic disc and was also expressed in epiblast cells located in the anterior primitive streak. Together with serial sections of embryos stained by whole mount immunohistochemistry, the mesoderm differentiation pattern was shown as an ingression movement that took place at the posterior of the embryonic disc and with bilateral migration along the embryonic disc borders.
Spermatogenesis is a process in adult male mammals supported by spermatogonial stem cells (SSCs). The cultivation of SSCs has potential value, for example for the treatment of male infertility or spermatogonial transplantation. Testicular interstitial fluid was added to culture medium to a final concentration of 5, 10, 20, 30 or 40%, in order to investigate its effects on proliferation of mouse SSCs in vitro, Alkaline phosphatase (AKP) assay, reverse transcription polymerase chain reaction (RT-PCR) analysis and indirect immunofluorescence of cells were performed to identify SSCs, and the proliferation rate and diameters of the SSCs colonies were measured. The results showed that the optimal addition of testicular interstitial fluid to culture medium was 30%. When medium supplemented with 30% testicular interstitial fluid was used to culture mouse SSCs, the optimum proliferation rate and diameter of the cell colonies were 72.53% and 249 μm, respectively, after 8 days in culture, values that were significant higher than those found for other groups (P < 0.05). In conclusion, proliferation of mouse SSCs could be promoted significantly by supplementation of the culture medium with 30% testicular interstitial fluid. More research is needed to evaluate and understand the precise physiological role of testicular interstitial fluid during cultivation of SSCs.