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Cinnamomum chago is a woody species of the family Lauraceae endemic to Yunnan province, China, previously known from only one location, and categorized as a Plant Species with Extremely Small Population. We surveyed to determine the distribution and population size of C. chago, characterize its habitat, identify any threats, assess its conservation status, and provide guidelines for its management and conservation. During 2014–2017 we found only 64 mature C. chago, in five locations. These small, fragmented populations occur along Lancang River in Dali Prefecture at altitudes of 2,200–2,400 m. The species' extent of occurrence is c. 923 km2, with an area of occupancy of c. 60 km2. The habitat of the species has been degraded by expansion of pastoral activities and deforestation. We recommend categorization of C. chago as Endangered on the IUCN Red List, prevention of the collection of seeds and wood of the species, protection and monitoring, and ex situ propagation for future reintroductions.
Novel NiMoO4-integrated electrode materials were successfully prepared by solvothermal method using Na2MoO4·2H2O and NiSO4·6H2O as main raw materials, water, and ethanol as solvents. The morphology, phase, and structure of the as-prepared materials were characterized by SEM, XRD, Raman, and FT-IR. The electrochemical properties of the materials in supercapacitors were investigated by cyclic voltammetry, constant current charge–discharge, and electrochemical impedance spectroscopy techniques. The effects of volume ratio of water to ethanol (W/E) in solvent on the properties of the product were studied. The results show that the pure phase monoclinic crystal NiMoO4 product can be obtained when the W/E is 2:1. The diameter and length are 0.1–0.3 µm and approximately 3 µm, respectively. As an active material for supercapacitor, the NiMoO4 nanorods material delivered a discharge specific capacitance of 672, 498, and 396 F/g at a current density of 4, 7, and 10 A/g, respectively. The discharge specific capacitance slightly decreased from 815 to 588 F/g with a retention of 72% after 1000 cycles at a current density of 1 A/g. With these superior capacitance properties, the novel NiMoO4 integrated electrode materials could be considered as promising material for supercapacitors.
Chickenpox is a common acute and highly contagious disease in childhood; moreover, there is currently no targeted treatment. Carrying out an early warning on chickenpox plays an important role in taking targeted measures in advance as well as preventing the outbreak of the disease. In recent years, the infectious disease dynamic model has been widely used in the research of various infectious diseases. The logistic differential equation model can well demonstrate the epidemic characteristics of epidemic outbreaks, gives the point at which the early epidemic rate changes from slow to fast. Therefore, our study aims to use the logistic differential equation model to explore the epidemic characteristics and early-warning time of varicella. Meanwhile, the data of varicella cases were collected from first week of 2008 to 52nd week of 2017 in Changsha. Finally, our study found that the logistic model can be well fitted with varicella data, besides the model illustrated that there are two peaks of varicella at each year in Changsha City. One is the peak in summer–autumn corresponding to the 8th–38th week; the other is in winter–spring corresponding to the time from the 38th to the seventh week next year. The ‘epidemic acceleration week’ average value of summer–autumn and winter–spring are about the 16th week (ranging from the 15th to 17th week) and 45th week (ranging from the 44th to 47th week), respectively. What is more, taking warning measures during the acceleration week, the preventive effect will be delayed; thus, we recommend intervene during recommended warning weeks which are the 15th and 44th weeks instead.
This study investigated the effect of pre-exercise α-lactalbumin ingestion on subsequent endurance exercise performance, muscle pain and mood states. In a two-stage cross-over counterbalance design, eleven male endurance runners (age: 31 (se 2) years, height: 169·5 (se 4·4) cm, weight: 63·6 (se 5·1) kg, V̇O2max: 58·8 (se 6·3) ml/kg per min) consumed two solutions (carbohydrate+α-lactalbumin, CA; carbohydrate+whey protein isolate, CW) 2 h before a self-paced 21-km run. Creatine kinase, IL-6, muscle pain, pressure pain threshold (PPT) and mood states were assessed 2 h before exercise, immediately before exercise (Pre-ex0) and immediately after exercise (Post-ex0). No difference was found in 21-km running performance between two trials (CA v. CW: 115·85 (se 5·20) v. 118·85 (se 5·51) min, P=0·48). Compared with CW, CA led to higher PPT at Pre-ex0 (41·77 (se 2·27) v. 35·56 (se 2·10) N/cm2, P<0·01) and Post-ex0 (38·76 (se 3·23) v. 35·30 (se 3·55) N/cm2, P=0·047). Compared with CW, CA reduced the feeling of fatigue at Post-ex0 (P<0·01); CA also reduced salivary cortisol levels at Post-ex0 (0·72 (se 0·07) v. 0·83 (se 0·13) ng/ml, P<0·01). In conclusion, the ingestion of α-lactalbumin did not improve the 21-km time-trial performance. However, compared with the pre-exercise ingestion of whey protein, that of α-lactalbumin led to superior results during similar levels of endurance exercise: it elevated PPT and reduced the feeling of fatigue and the cortisol levels.
The Cu–S compounds have been reported as promising thermoelectric materials with abundant element composition, low price, and low toxicity. In this work, SnxCu1.8−xS samples with different Sn contents (x = 0.005, 0.01, 0.03, and 0.05) were fabricated by mechanical alloying combined with spark plasma sintering. The phase structure and microstructure of all the bulk samples were checked by X-ray diffraction (XRD) and field emission scanning electron microscopy respectively. The thermoelectric transport properties, such as electrical conductivity, Seebeck coefficient, carrier concentration, carrier mobility, and thermal conductivity, were measured. The effect of second phase introduced by Sn addition on the thermoelectric properties of Cu–S system was investigated. The thermoelectric properties of samples were improved by the precipitations of two different second phases (Cu2SnS3 and Cu4SnS4). The second phase species depend on the Sn contents. Finally, the Sn0.01Cu1.79S bulk sample obtained the highest ZT value of 0.81 at 773 K, which is 1.6-fold higher than that of the pristine Cu1.8S sample due to the significantly reduced thermal conductivity by second phase and nanopores scattering.
The novel Three-dimensional rambutan-like NiCo2O4 microspheres have been successfully coated onto surface of carbon nanofibers (CNFs) to form NiCo2O4–CNFs hybrids. The composition and microstructure of NiCo2O4–CNFs were characterized by the field-emission scanning electronmicroscopy, x-ray photoelectron spectroscopy, transmission electron microscopy, and x-ray diffractometer. The obtained NiCo2O4–CNFs exhibited a specific capacity of 160 mAh/g at 1 mA/cm2 in 2 M potassium hydroxide aqueous solution. The specific capacity gradually increases with the increasing of cycles; and after 3000 cycles, the specific capacity still can be remained over 90%.
Rapid progress in the stellar pulsation research has presented many new challenges to traditional pulsation theory. The following progress made by us should belong to one of the new challenges:
1)There are many variable stars located at the Horizontal Branch (HB) but outside the instability strip with amplitude larger than 0.02 mag.
Maybe some astronomers have already doubted of the 1950’s conclusion-the RR Lyrae stars are confined to the narrow instability strip in the C-M diagram, the boundaries of the gap are extremely sharp and definite, beyond the edges no light variations occur with ranges greater than 0.02 mag. We are changing the conclusion by observations. Here we do not mean the microvariability. We still raise the question from the classical viewpoint. We want to show that there are variable stars outside the strip with peak to peak amplitudes larger than 0.02 mag.
In this paper, hierarchical nanostructures of BiOBr/AgBr on electrospun carbon nanofibers (CNFs) were prepared by combination of electrospinning and carbonization. Compared with the smooth surface of CNFs, the rough surface with hierarchical nanostructures of BiOBr/AgBr can be obtained by adding the certain amount of BiOBr/AgBr precursors into the spinning solution. The as-prepared composite CNFs exhibited highly photocatalytic activities for degradation of rhodamine-B and reduction of p-nitrophenol under the visible-light irradiation and at room temperature. Furthermore, the as-prepared composite CNFs showed the favor separation, recovery, and cyclic utilization properties.
Recent studies have suggested an association between vitamin D and non-alcoholic fatty liver disease (NAFLD); however, some results are subject to debate. This study was carried out to evaluate the correlation between NAFLD and vitamin D in men and women in East China. The data were obtained from a cross-sectional study that focused on the health and metabolic status of adults in sixteen areas of East China. According to ultrasonic assessments, the patients were divided into normal and NAFLD groups. Demographic characteristics and biochemical measurements were obtained. Binary logistic regression analysis was used to explore the association. In total, 5066 subjects were enrolled, and 2193 (43·3 %) were diagnosed with NAFLD; 84·56 % of the subjects showed vitamin D deficiency. Subjects with high vitamin D levels had a lower prevalence of NAFLD, particularly male subjects. Within the highest quartile of vitamin D levels, the prevalence of NAFLD was 40·8 %, whereas the lowest quartile of vitamin D levels showed a prevalence of 62·2 %, which was unchanged in women across the vitamin D levels. Binary logistic analysis showed that decreased vitamin D levels were associated with an increased risk of NAFLD (OR 1·54; 95 % CI 1·26, 1·88). This study suggests that vitamin D levels are significantly associated with NAFLD and that vitamin D acts as an independent factor for NAFLD prevalence, particularly in males in East China. Vitamin D interventional treatment might be a new target for controlling NAFLD; elucidating the mechanism requires further research.
In this work, we developed a convenient way to immobilize silver nanoparticles on the aminated polyacrylonitrile (PAN) nanofibrous mats by combing the electrospinning technology from complex-containing polymer solution, amination of PAN nanofibrous and electroless plating technique. The resultant composite nanaofibrous mats had been characterized by scanning electron microscopy, energy-dispersive spectrometer, transmission electron microscopy, X-ray diffraction, and Fourier transform infrared spectra analysis. The catalytic activity and stability of these resultant composite nanofibrous mats for the catalytic reactions, including reduction of 4-nitrophenol to form 4-aminophenol, and selective oxidation of benzyl alcohol, were investigated. The resultant nanofibrous mats exhibited high-efficiency, convenient separation, recovery, and cyclic utilization properties.
The Mn-doped ZrO2/TiO2 nanostructured photocatalysts had been prepared by the simple hydrothermal method. The morphologies and structures of the as-prepared photo-catalyst were characterized by transmission electron microscopy, x-ray diffraction, x-ray photoelectron spectroscopy, and electron paramagnetic resonance. The resultant nanostructured photocatalysts exhibited high photocatalytic activity under ultraviolet (UV) light irradiation, attributing to the improvement of the photo-absorption property and the separation efficiency of photo-generated electrons and holes. The hydroxyl radicals (•OH), superoxide radical (•O2−), and holes (h+) are the main active species in aqueous solution under UV light irradiation.
Dielectric thin films of high- and low-refractive index are the essential components for optical coatings. To achieve high sputtering rates and superior film quality, the authors have developed novel conductive SiO2:Si and ZnO:Zn composites that become conductive once the doped silicon and metal Zn reach a critical ratio. The sputtering characteristics of the composite targets in direct current and radio-frequency (RF) plasma discharge are quite different from the corresponding element targets. The optical properties of the RF sputtered SiO2 and ZnO films from the composite targets is comparable with the films obtained from RF sputtering of pure oxide targets.
Dietary fibre intake has been suggested to reduce blood glucose levels in diabetic patients, particularly when glycosylated Hb (HbA1c) levels are high. In the present study, we used a quantile regression (QR) approach to characterise the possible heterogeneous associations of dietary fibre intake with HbA1c levels in Chinese diabetic patients. A total of 497 diabetic patients participated in the baseline survey in 2006 and in the follow-up survey in 2011, both of which were conducted in Pudong New Area of Shanghai, China. Structured in-person interviews were conducted to collect information on demographic characteristics and lifestyle factors. Dietary intake was assessed using a validated FFQ. Blood samples were collected during the interviews for biochemical assays. QR models were used to examine the heterogeneous associations of dietary factors with HbA1c levels. A significant marginal association of insoluble dietary fibre intake with subsequent HbA1c levels was observed only when the HbA1c level was over 6·8 %. The associations appeared to be greater when the quantile levels of HbA1c were higher. The coefficient estimates were − 0·174 (95 % CI − 0·433, − 0·025) at the quantile of 0·60, − 0·200 (95 % CI − 0·306, − 0·008) at 0·70, − 0·221 (95 % CI − 0·426, − 0·117) at 0·80, and − 0·389 (95 % CI − 0·516, − 0·018) at 0·90. A similar pattern was observed for the associations of dietary glycaemic index (GI) value with HbA1c levels. In conclusion, the present results indicate that the associations of insoluble dietary fibre intake and GI value with subsequent HbA1c levels depend on glycaemic control status in Chinese diabetic patients. More studies are required to confirm our findings.
The high repetition rate 10 J/10 ns Yb:YAG laser system and its key techniques are reported. The amplifiers in this system have a multi-pass V-shape structure and the heat in the amplifiers is removed by means of laminar water flow. In the main amplifier, the laser is four-pass, and an approximately 8.5 J/1 Hz/10 ns output is achieved in the primary test. The far-field of the output beam is approximately 10 times the diffraction limit. Because of the higher levels of amplified spontaneous emission (ASE) in the main amplifier, the output energy is lower than expected. At the end we discuss some measures that can improve the properties of the laser system.
This study was designed to determine the effect of melatonin on the in vitro maturation (IVM) and developmental potential of bovine oocytes denuded of the cumulus oophorus (DOs). DOs were cultured alone (DOs) or with 10−9 M melatonin (DOs + MT), cumulus–oocyte complexes (COCs) were cultured without melatonin as the control. After IVM, meiosis II (MII) rates of DOs, and reactive oxygen species (ROS) levels, apoptotic rates and parthenogenetic blastocyst rates of MII oocytes were determined. The relative expression of ATP synthase F0 Subunit 6 and 8 (ATP6 and ATP8), bone morphogenetic protein 15 (BMP-15) and growth differentiation factor 9 (GDF-9) mRNA in MII oocytes and IFN-tau (IFN-τ), Na+/K+-ATPase, catenin-beta like 1 (CTNNBL1) and AQP3 mRNA in parthenogenetic blastocysts were quantified using real-time polymerase chain reaction (PCR). The results showed that: (1) melatonin significantly increased the MII rate of DOs (65.67 ± 3.59 % vs. 82.29 ± 3.92%; P < 0.05), decreased the ROS level (4.83 ± 0.42 counts per second (c.p.s) vs. 3.78 ± 0.29 c.p.s; P < 0.05) and apoptotic rate (36.99 ± 3.62 % vs. 21.88 ± 2.08 %; P < 0.05) and moderated the reduction of relative mRNA levels of ATP6, ATP8, BMP-15 and GDF-9 caused by oocyte denudation; (2) melatonin significantly increased the developmental rate (24.17 ± 3.54 % vs. 35.26 ± 4.87%; P < 0.05), and expression levels of IFN-τ, Na+/K+-ATPase, CTNNBL1 and AQP3 mRNA of blastocyst. These results indicated that melatonin significantly improved the IVM quality of DOs, leading to an increased parthenogenetic blastocyst formation rate and quality.
Dietary fibre has been linked to lower levels of glycosylated haemoglobin A1c (HbA1c) among diabetes patients. The present study aimed to evaluate the long-term effect of dietary fibre on HbA1c levels among Chinese patients with type 2 diabetes mellitus.
Two cross-sectional surveys were conducted in 2006 and 2011, with the second one being a repeat survey on a sub-sample from the initial one. In both surveys, an in-person interview was conducted to collect information on demographic characteristics and lifestyles following a similar protocol. Dietary intake was assessed with a validated FFQ. Anthropometric measures and biochemical assays were performed at the interview.
Communities in Pudong New Area of Shanghai, China.
Chinese patients (n 934) with type 2 diabetes mellitus.
An inverse association was observed between dietary fibre and glycaemic status indicated by HbA1c level in both surveys, although it was significant only in the first survey. Among 497 patients participating in both surveys, dietary fibre intake at the first survey was inversely associated with uncontrolled glycaemic status at the second survey, with adjusted odds ratios across the tertiles of intake being 1·00, 0·72 (95 % CI 0·43, 1·21) and 0·58 (95 % CI 0·34, 0·99; Ptrend = 0·048). The change in fibre intake was slightly associated with glycaemic status, with each increase in tertile scores of intake linked to a 0·138 % (β = −0·138; 95 % CI −0·002, 0·278) decrease in HbA1c value and a 19 % (OR = 0·81; 95 % CI 0·65, 1·02) reduced risk of uncontrolled glycaemic status at the second survey.
Dietary fibre may have a long-term beneficial effect on HbA1c level among Chinese diabetes patients.
A joint diagnostic system was established for the diagnosis of laser-driven shock wave experiments. The system has high temporal resolution (time resolution ~12 ps) and high spatial resolution (spatial resolution ~7 μm) and fits for diagnostics of the experiment with small sample size and short time physical process. The joint diagnostic system was applied for shock wave measurement on the Shenguang-II laser facility. The passive shock breakout signal and active diagnostic signal were simultaneously obtained. The temporal measurement reliability of the system was verified using a multi-layered target. The experimental results show that the two measurement results were consistent.
Photoperiods influence diapause beyond the maternal generation in Cotesia vestalis (Haliday) (Hymenoptera: Braconidae). The sizes, 20-hydroxyecdysone (20E), and juvenile hormone III (JH III) contents in the G1 diapausing prepupae, G0 nondiapausing prepupae, adults, and G1 eggs from C. vestalis cultures reared under three photoperiods (8:16 hours light:dark, 12:12 hours light:dark, and 16:8 hours light:dark) were measured to investigate the hormones’ roles on maternal information transmission and diapause regulation. Results showed that the body size of G1 diapausing prepupae was significantly larger than that of G0 nondiapausing prepupae. The sizes of G0 prepupae, female abdomens, and G1 eggs under eight-hour light were significantly larger than those under 16-hour light. The 20E content in diapausing prepupae was significantly lower than that in nondiapausing prepupae, whereas JH III content did not show significantly difference under the same photoperiod. The 20E content in maternal prepupae, mated females and G1 eggs decreased as the light period was reduced. Juvenile hormone III contents in G0-mated females and G1 eggs (after oviposition) under three photoperiods showed no significant differences. These findings suggest that 20E may play a critical role in diapause regulation of C. vestalis, and be used as a maternal environmental message to be transmitted to the next generation.
We investigated the effect mouse cumulus cells (mCCs) on the in vitro maturation (IVM) and developmental potential of bovine denuded germinal vesicle oocytes (DOs). Cumulus–oocyte complexes (COCs), DOs and DOs cocultured with either mCCs (DOs + mCCs) or bovine cumulus cells (bCCs; DOs + bCCs) were subjected to IVM. The meiosis II (MII) rates of DOs, glutathione (GSH) contents, zona pellucida (ZP) hardening and parthenogenetic blastocyst rates of MII oocytes were determined. The relative expression levels of bone morphogenetic protein 15 (BMP-15) and growth differentiation factor 9 (GDF-9) in MII oocytes were measured using quantitative real-time polymerase chain reaction (PCR). mCCs significantly increased the MII rate of DOs from 53.5 ± 3.58% to 69.67 ± 4.72% (p < 0.05) but had no effect on the GSH content (2.17 ± 0.31 pmol/oocyte with mCCs, 2.14 ± 0.53 pmol/oocyte without mCCs). For the DOs + mCCs group, the BMP-15 and GDF-9 expression levels were significantly higher and the ZP dissolution time was significantly lower (162.49 ± 12.51 s) than that of the DOs group (213.95 ± 18.87 s; p < 0.05). The blastocyst rate of the DOs + mCCs group (32.56 ± 4.94%) was similar to that of the DOs group (31.75 ± 3.65%) but was significantly lower than that of the COCs group (43.52 ± 5.37%; p < 0.05). In conclusion, mCCs increased the MII rate of DOs and expression of certain genes in MII oocytes, and decreased the ZP hardening of MII oocytes, but could not improve their GSH content or developmental potential.