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The purpose of this retrospective study was to optimize the transplantation strategy for women of advanced maternal age to achieve live births within the shortest time. Data were collected from patients older than 40 years who underwent assisted reproductive therapy at our centre from 1 January 2009 to 31 December 2019. In total, 1023 cases of fresh cleavage embryo transfer (CET) cycles, 280 cases of frozen–thawed blastocyst transfer (FBT) cycles, and 26 cases of frozen–thawed CET (FCET) cycles were included. The main outcome was the live birth rate (LBR). The secondary outcomes were the clinical pregnancy rate (CPR) and neonatal outcomes. Multivariable logistic regression was performed to adjust for confounding factors. The blastocyst formation rate of patients older than 40 years was 23.5%, the freezing cycle rate was 19.8%, and the fresh-embryo transfer rate was 83.0%. The implantation rate, CPR, and LBR were significantly different among the CET, FCET, and FBT groups. There were no significant differences in multiple pregnancies and abortion rates among the groups, and neonatal outcomes were similar. Multivariate logistic regression analysis showed that, compared with the CET group, LBR did not increase in the FCET group, whereas LBR increased in the FBT group. For patients older than 40 years when having approximately eight embryos after fertilization, blastocyst transfer can be considered after fully discussing the advantages and disadvantages of blastocyst culture. Alternatively, CET can be performed first, followed by FBT if the cleavage embryo transfer is unsuccessful.
We demonstrate an efficient ultrafast source with 195 fs pulse duration, 54 W average power at 200 kHz repetition rate and near diffraction-limited beam quality. The compact setup incorporates a thin-disk Yb:YAG regenerative amplifier (RA) and a subsequent nonlinear pulse compression stage with periodic-layered Kerr media (PLKM), which is one of the multiple-thin-solid-plate schemes based on nonlinear resonator theory. In virtue of the formation of quasi-stationary spatial soliton in PLKM, the near diffraction-limited beam quality of the RA remained almost undisturbed after post-compression. The nonlinear pulse compression module is simple and efficient with a transmission of 96%. To the best our knowledge, for pulse energy over 200 μJ, this is the highest output power reported for the multiple-thin-solid-plate scheme. This source manifests an economical combination to mitigate the bandwidth limitations of Yb-based high-power chirped pulse amplifiers.
South-west China, particularly between the Himalayas and the Beibu Gulf, constitutes an important corridor for migratory raptors along the East-Asian continental flyway. However, a lack of ornithological assessment and the common practice of illegal hunting in this region emphasize the need for research and conservation actions. To investigate the ecology of migration and scale of persecution, we launched one of the first citizen-science projects in mainland China to record southward-migrating raptors and hunting gunshots from 2015 to 2019 on Guantouling, a well-known raptor site in South-west China. A total of 42,891 raptors were recorded, belonging to 30 diurnal raptor species. Grey-faced Buzzard Butastur indicus, Oriental Honey Buzzard Pernis ptilorhynchus and Amur Falcon Falco amurensis were the three most abundant species recorded. The bulk of Grey-faced Buzzard and Amur Falcon migrated through Guantouling from mid-October till early November, while Oriental Honey Buzzard migrated throughout October and early November. Precipitation slowed down migration significantly while increasing cloud cover was favoured by the three most abundant species. We found hunting mostly occurred in the afternoon, coinciding with an increasing number of Oriental Honey Buzzard, which may become a major victim of hunting. It is thus suggested to prioritize peak raptor migration period for law enforcement actions, especially on cloudy days and after passage of cold fronts, when Oriental Honey Buzzards and other species are likely to migrate. The annual counting scheme on Guantouling is not only an ecological survey, but also an effective way of engaging the public to counter raptor persecution.
Chronic inflammation exerts pleiotropic effects in the aetiology and progression of chronic obstructive pulmonary disease (COPD). Glucosamine is widely used in many countries and may have anti-inflammatory properties. We aimed to prospectively evaluate the association of regular glucosamine use with incident COPD risk and explore whether such association could be modified by smoking in the UK Biobank cohort, which recruited more than half a million participants aged 40–69 years from across the UK between 2006 and 2010. Cox proportional hazards models with adjustment for potential confounding factors were used to calculate hazard ratios (HR) as well as 95 % CI for the risk of incident COPD. During a median follow-up of 8·96 years (interquartile range 8·29–9·53 years), 9016 new-onset events of COPD were documented. We found that the regular use of glucosamine was associated with a significantly lower risk of incident COPD with multivariable adjusted HR of 0·80 (95 % CI, 0·75, 0·85; P < 0·001). When subgroup analyses were performed by smoking status, the adjusted HR for the association of regular glucosamine use with incident COPD were 0·84 (0·73, 0·96), 0·84 (0·77, 0·92) and 0·71 (0·62, 0·80) among never smokers, former smokers and current smokers, respectively. No significant interaction was observed between glucosamine use and smoking status (Pfor interaction = 0·078). Incident COPD could be reduced by 14 % to 84 % through a combination of regular glucosamine use and smoking cessation.
Operation of tools has long been studied in robotics. Although appropriate hold of the tool by robots is the base of successful tool operation, it is not with ease especially for tools with complicated shape. In this paper, an assist system for a four-limbed robot is proposed for remote operation of reaching and grasping electric drills using deep reinforcement learning. Through comparative evaluation experiments, the increase of success rate for reaching and grasping is verified and the decrease in both physical and mental workload of the operator is also validated by the index of NASA-TLX.
Drilling and sampling are the most direct and effective methods available to study Antarctic subglacial lakes. Based on the Philberth probe, a Recoverable Autonomous Sonde (RECAS) allows for in situ lake water measurement and sampling, through the addition of an upper thermal tip and a cable recoiling mechanism. RECAS-200, a prototype of RECAS, has a drilling depth of 200 m, a surface supply voltage of 800 VAC and a downhole power of ~9.6 kW during drilling. In this study, a heating control system for RECAS-200 was designed. The system avoids the need for high-power step-down converters, by separating heating power from control power, thereby reducing the overall weight of the probe and avoiding the need to increase cable diameter. We also introduce a self-developed, small, solid-state, 800 VAC power regulator and a fuzzy PID temperature control algorithm. Their purpose was to manage the power adjustment of each heating element and to provide closed-loop temperature control of certain heating elements which can easily burn out due to overheating. Test results indicated that the proposed RECAS-200 heating control system met all our design specifications and could be easily assembled into the RECAS-200 probe.
Subglacial lake exploration is of great interest to the science community. RECoverable Autonomous Sonde (RECAS) provides an exploration tool to measure and sample subglacial lake environments while the subglacial lake remains isolated from the glacier surface and atmosphere. This paper presents an electronic control system design of 200 m prototype of RECAS. The proposed electronic control system consists of a surface system, a downhole control system, and a power transfer and communication system. The downhole control system is the core element of RECAS, and is responsible for sonde status monitoring, sonde motion control, subglacial water sampling and in situ analysis. A custom RS485 temperature sensor was developed to cater for the limited size and depth requirements of the system. We adopted a humidity-based measurement to monitor for a housing leak. This condition is because standard leak detection monitoring of water conductivity may be inapplicable to pure ice in Antarctica. A water sampler control board was designed to control the samplers and monitor the on/off state. A high-definition camera system with built-in storage and self-heating ability was designed to perform the video recording in the subglacial lake. The proposed electronic control system is proven effective after a series of tests.
Seaweeds have numerous biologically active ingredients, such as polysaccharides, polyphenols and carotenoids, that are beneficial to human health. Although these benefits might be related to the synthesis, secretion or reabsorption of uric acid, no studies have explored the relationship between seaweeds consumption and hyperuricaemia (HUA) in the general population. The aim of this study was to investigate whether seaweeds consumption is related to HUA in a large-scale adult population. A cross-sectional study was conducted with 32 365 adults (17 328 men and 15 037 women) in Tianjin, People’s Republic of China. Frequency of seaweeds consumption was assessed by a validated self-administered FFQ. HUA was defined as serum uric acid levels >420 μmol/L in men and >350 μmol/L in women. The association between seaweeds consumption and HUA was assessed by multiple logistic regression analysis. Restricted cubic spline functions were used for non-linearity tests. The prevalence of HUA in men and women was 21·17 % and 5·93 %, respectively. After adjustments for potential confounding factors, the OR (95 % CI) for HUA across seaweed consumption (g/1000 kcal per d) were 1·00 (reference) for level 1, 0·91 (95 % CI 0·81, 1·02) for level 2; 0·90 (95 % CI 0·81, 1·01) for level 3; 0·86 (95 % CI 0·78, 0·97) for level 4 in men and 0·90 (95 % CI 0·73, 1·10) for level 2; 0·82 (95 % CI 0·67, 1·00) for level 3; 0·84 (95 % CI 0·68, 1·03) for level 4 in women, respectively. A negative correlation between seaweeds consumption and HUA in males but not in females was observed. Further studies are needed to explore the causal relationship.
Stable isotope ratios (δ18O and δD) in Antarctic snow and ice are basic proxy indices of climate in ice core studies. The relation between the ratios has important indicative significance for moisture sources. In general, the fractionation characteristics of the two isotopes vary with different meteorological and topographical conditions. This paper presents the spatial and temporal distribution of meteoric water line (MWL) slopes along a traverse from the Zhongshan Station (ZSS) to Dome A in East Antarctica. It is found that the slopes decrease with the increasing distance inland from the coast and the lowest slope occurred at Dome A, where the long-range transported moisture dominates and clear sky snowing have an influence. The slopes in different layers of the snowpack showed a decreasing trend with depth and this is attributed to the fractionation during the interstitial sublimation and re-condensation processes of the water vapor. Frost flower development on the interior plateau surface can greatly alter the depth evolution of the MWL slope. The coastal snow pits also go through the post-depositional smoothing effect, but their influences are not so significant as the inland regions.
More than 50% patients with major depressive disorder (MDD) have severe functional impairment. The restoration of patient functioning is a critical therapeutic goal among patients with MDD. We conducted a systematic review and network meta-analysis to evaluate the efficacy of pharmacological treatments on self-rated functional outcomes using the Sheehan Disability Scale in adults with MDD in randomized clinical trials.
PubMed, EMBASE, PsycINFO, Cochrane Library, and ClinicalTrials.gov were searched from inception to December 10, 2019. Summary statistics are reported as weighted mean differences with 95% confidence intervals. Interventions were ranked using the surface under the cumulative ranking probabilities.
We included 42 randomized controlled trials (RCTs) (n = 18 998) evaluating the efficacy of 13 different pharmacological treatments on functional outcomes, as measured by the Sheehan Disability Scale (SDS). Duloxetine was the most effective pharmacological agent on functional outcomes, followed by (ranked by efficacy): paroxetine, levomilnacipran, venlafaxine, quetiapine, desvenlafaxine, agomelatine, escitalopram, amitriptyline, bupropion, sertraline, vortioxetine, and fluoxetine. Serotonin and norepinephrine reuptake inhibitors were more effective than other drug classes. Additionally, the comparison-adjusted funnel plot suggested the publication bias between small and large studies was relatively low.
Our results indicate that there may be differences across antidepressant agents and classes with respect to self-reported functional outcomes. Validation and replication of these findings in large-scale RCTs are warranted. Our research results will be clinically useful for guiding psychiatrists in treating patients with MDD and functional impairment. PROSPERO registration number CRD42018116663.
GBF1 [Golgi brefeldin A (BFA) resistance factor 1] is a member of the guanine nucleotide exchange factors Arf family. GBF1 localizes at the cis-Golgi and endoplasmic reticulum (ER)-Golgi intermediate compartment where it participates in ER-Golgi traffic by assisting in the recruitment of the coat protein COPI. However, the roles of GBF1 in oocyte meiotic maturation are still unknown. In the present study, we investigated the regulatory functions of GBF1 in mouse oocyte organelle dynamics. In our results, GBF1 was stably expressed during oocyte maturation, and GBF1 localized at the spindle periphery during metaphase I. Inhibiting GBF1 activity led to aberrant accumulation of the Golgi apparatus around the spindle. This may be due to the effects of GBF1 on the localization of GM130, as GBF1 co-localized with GM130 and inhibiting GBF1 induced condensation of GM130. Moreover, the loss of GBF1 activity affected the ER distribution and induced ER stress, as shown by increased GRP78 expression. Mitochondrial localization and functions were affected, as the mitochondrial membrane potential was altered. Taken together, these results suggest that GBF1 has wide-ranging effects on the distribution and functions of Golgi apparatus, ER, and mitochondria as well as normal polar body formation in mouse oocytes.
The upsurge in the number of people affected by the COVID-19 is likely to lead to increased rates of emotional trauma and mental illnesses. This article systematically reviewed the available data on the benefits of interventions to reduce adverse mental health sequelae of infectious disease outbreaks, and to offer guidance for mental health service responses to infectious disease pandemic. PubMed, Web of Science, Embase, PsycINFO, WHO Global Research Database on infectious disease, and the preprint server medRxiv were searched. Of 4278 reports identified, 32 were included in this review. Most articles of psychological interventions were implemented to address the impact of COVID-19 pandemic, followed by Ebola, SARS, and MERS for multiple vulnerable populations. Increasing mental health literacy of the public is vital to prevent the mental health crisis under the COVID-19 pandemic. Group-based cognitive behavioral therapy, psychological first aid, community-based psychosocial arts program, and other culturally adapted interventions were reported as being effective against the mental health impacts of COVID-19, Ebola, and SARS. Culturally-adapted, cost-effective, and accessible strategies integrated into the public health emergency response and established medical systems at the local and national levels are likely to be an effective option to enhance mental health response capacity for the current and for future infectious disease outbreaks. Tele-mental healthcare services were key central components of stepped care for both infectious disease outbreak management and routine support; however, the usefulness and limitations of remote health delivery should also be recognized.
For a wide range of insect species, the microbiota has potential roles in determining host developmental programme, immunity and reproductive biology. The tea geometrid moths Ectropis obliqua and E. grisescens are two closely related species that mainly feed on tea leaves. Although they can mate, infertile hybrids are produced. Therefore, these species provide a pair of model species for studying the molecular mechanisms of microbiotal involvement in host reproductive biology. In this study, we first identified and compared the compositions of microbiota between these sibling species, revealing higher microbiotal diversity for E. grisescens. The microbiota of E. obliqua mainly comprised the phyla Firmicutes, Proteobacteria and Cyanobacteria, whereas that of E. grisescens was dominated by Proteobacteria, Actinobacteria and Firmicutes. At the genus level, the dominant microbiota of E. grisescens included Wolbachia, Enterobacter and Pseudomonas and that of E. obliqua included Melissococcus, Staphylococcus and Enterobacter. Furthermore, we verified the rate of Wolbachia to infect 80 samples from eight different geographical populations, and the results supported that only E. grisescens harboured Wolbachia. Taken together, our findings indicate significantly different microbiotal compositions for E. obliqua and E. grisescens, with Wolbachia possibly being a curial factor influencing the reproductive isolation of these species. This study provides new insight into the mechanisms by which endosymbiotic bacteria, particularly Wolbachia, interact with sibling species.
The Antarctic subglacial drilling rig (ASDR) is designed to recover 105 mm-diameter ice cores up to 1400 m depth and 41.5 mm-diameter bedrock cores up to 2 m in length. In order to ensure safe and convenient drilling, drilling auxiliaries are designed to support fieldwork and servicing. These auxiliaries are subdivided into several systems for power supply, drill tripping in the borehole, ice core and chip processing, and drill servicing and maintenance. The required equipment also includes two generators, a drilling winch with a cable, logging winch with a cable, control desk, pipe handler with a fixed clamp, chip chamber vibrator, centrifuge, emergency devices and fitting and electrical tools. Additionally, several environmental protective measures such as a new liquid-tight casing with a thermal casing shoe and a bailing device for recovering drilling fluid from the borehole were designed. Most of the auxiliaries were tested during the summer of 2018–2019 near Zhongshan Station, East Antarctica while drilling to the bedrock to a depth of 198 m.
A new, modified version of the cable-suspended Ice and Bedrock Electromechanical Drill (IBED) was designed for drilling in firn, ice, debris-rich ice and rock. The upper part of the drill is almost the same for all drill variants and comprises four sections: cable termination, a slip-ring section, an antitorque system and an electronic pressure chamber. The lower part of the IBED comprises an auger core barrel, reamers, a core barrel for ice/debris-ice drilling and a conventional geological single-tube core barrel or custom-made double-tube core barrel. First, the short and full-scale field versions of the IBED were tested at an outdoor testing stand and a testing facility with a 12.5 m-deep ice well. Then, in the 2018–2019 summer season, the IBED was tested in the field at a site ~12 km south of Zhongshan Station, East Antarctica, and a ~6 cm bedrock core was recovered from a 198 m-deep borehole. A total of 18 d was required to penetrate the ice sheet. The retrieved core samples of blue ice, basal ice and bedrock provided valuable information regarding the Earth's paleo-environment.
This study examined the within- and cross-language metalinguistic contribution of three components of metalinguistic awareness (i.e., phonological awareness, morphological awareness, and syntactic awareness) to reading comprehension in monolingual Chinese-speaking children from Mainland China (n = 190) and English–Chinese bilingual children from Singapore (n = 390). Moreover, the effect of home language use on the relationship between metalinguistic awareness and reading performance was investigated. For monolingual children, hierarchical regression analyses revealed that after partialing out the effects of age, nonverbal intelligence, and oral vocabulary, syntactic awareness uniquely predicted 7%–13% of the variance in reading comprehension measures, whereas this relationship was not observed between morphological awareness and reading comprehension. For the bilingual children, within-language regression analyses revealed that English/Chinese morphological awareness and syntactic awareness both contributed significantly to English/Chinese reading measures over and above vocabulary and phonological awareness. Cross-linguistically, structure equation modeling results demonstrated that the bilingual children’s English and Chinese metalinguistic awareness were closely related and jointly supported reading comprehension in both languages, thus lending support to Koda’s transfer facilitation model. Furthermore, home language use was found to contribute to the bilingual children’s reading proficiency via its impact on metalinguistic awareness. The paper concludes with a discussion of the policy and pedagogical implications that can be drawn from these findings.
A simple, compact, double-pass pumped Nd:YVO4 thin disk laser is demonstrated. Its continuous-wave performance with different Nd doping concentrations and thicknesses is investigated experimentally. The maximum output power of 17.7 W is achieved by employing a 0.5 at.% doped sample, corresponding to an optical-to-optical efficiency of 46% with respect to the absorbed pump power. In addition, a numerical analysis and an experimental study of the temperature distribution, and thermal lens effect of the Nd:YVO4 thin disk, are presented considering the influence of the energy transfer upconversion effect and the temperature dependence of the thermal conductivity tensor. The simulated results are in good agreement with the experimental results.
The interaction of the Palaeo-Pacific and Palaeo-Asian Oceans is an enigmatic issue as their temporal and spatial features are controversial. To address this issue, we present a systematic study of large volumes of early Permian volcanic rocks and intrusions developed in the East Tianshan. The represented samples of basaltic andesites and rhyolites yield zircon crystallization ages of 285.1 ± 5.9 Ma and 275.3 ± 1.8 Ma, respectively. The basalts have normal mid-ocean ridge basalt (N-MORB) and arc-related geochemical signatures with high TiO2 contents, negative Rb, Th, U, Nb and Ta anomalies and positive Eu anomalies. Basaltic andesites and andesites have arc-related geochemical characteristics with moderate TiO2 contents and relatively negative Nb, Ta and Ti anomalies, together with slightly negative to positive Eu anomalies. The rhyolites show an affinity with A2-type granite with high SiO2, K2O + Na2O, Fe/Mg, Ga, Zr, Nb, Y, HFSE, REE and Y/Nb levels (>1.2). These geochemical data suggest that the rocks formed in a supra-subduction zone. The presence of high ϵNd(t) values of +4.6 to +8.2 and low (87Sr/86Sr)i (0.70342–0.70591) values indicates that the volcanic rocks originated from a depleted mantle. We propose that oblique subduction with slabs breaking off gave rise to transtension and to the emplacement of large volumes of mantle-derived melts in the early Permian in the East Tianshan, serving as an important record of the subduction zone of the Palaeo-Pacific Ocean.