To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Understanding the patterns of treatment response is critical for the treatment of patients with schizophrenia; one way to achieve this is through using a longitudinal dynamic process study design.
This study aims to explore the response trajectory of antipsychotics and compare the treatment responses of seven different antipsychotics over 6 weeks in patients with schizoprenia (trial registration: Chinese Clinical Trials Registry Identifier: ChiCTR-TRC-10000934).
Data were collected from a multicentre, randomised open-label clinical trial. Patients were evaluated with the Positive and Negative Syndrome Scale (PANSS) at baseline and follow-up at weeks 2, 4 and 6. Trajectory groups were classified by the method of k-means cluster modelling for longitudinal data. Trajectory analyses were also employed for the seven antipsychotic groups.
The early treatment response trajectories were classified into a high-trajectory group of better responders and a low-trajectory group of worse responders. The results of trajectory analysis showed differences compared with the classification method characterised by a 50% reduction in PANSS scores at week 6. A total of 349 patients were inconsistently grouped by the two methods, with a significant difference in the composition ratio of treatment response groups using these two methods (χ2 = 43.37, P < 0.001). There was no differential contribution of high- and low trajectories to different drugs (χ2 = 12.52, P = 0.051); olanzapine and risperidone, which had a larger proportion in the >50% reduction at week 6, performed better than aripiprazole, quetiapine, ziprasidone and perphenazine.
The trajectory analysis of treatment response to schizophrenia revealed two distinct trajectories. Comparing the treatment responses to different antipsychotics through longitudinal analysis may offer a new perspective for evaluating antipsychotics.
To improve the endurance performance of long-endurance Unmanned Aerial Vehicles (UAVs), a smart morphing method to adjust the UAV and flight mode continuously during flight is proposed. Using this method as a starting point, a smart morphing long-endurance UAV design is conducted and the resulting improvement in the endurance performance studied. Firstly, the initial overall design of the smart morphing long-endurance UAV is carried out, then the morphing form is designed and various control parameters are selected. Secondly, based on multi-agent theory, an architecture for the smart morphing control system is built and the workflow of the smart morphing control system is planned. The morphing decision method is designed in detail based on the particle swarm optimisation algorithm. Finally, a simulation of the smart morphing approach in the climb and cruise stages is carried out to quantitatively verify the improvement in the endurance performance. The simulation results show that the smart morphing method can improve the cruise time by 4.1% with the same fuel consumption.
Shifts in the maternal gut microbiota have been implicated in the development of gestational diabetes mellitus (GDM). Understanding the interaction between gut microbiota and host glucose metabolism will provide a new target of prediction and treatment. In this nested case-control study, we aimed to investigate the causal effects of gut microbiota from GDM patients on the glucose metabolism of germ-free (GF) mice. Stool and peripheral blood samples, as well as clinical information, were collected from 45 GDM patients and 45 healthy controls (matched by age and prepregnancy body mass index (BMI)) in the first and second trimester. Gut microbiota profiles were explored by next-generation sequencing of the 16S rRNA gene, and inflammatory factors in peripheral blood were analyzed by enzyme-linked immunosorbent assay. Fecal samples from GDM and non-GDM donors were transferred to GF mice. The gut microbiota of women with GDM showed reduced richness, specifically decreased Bacteroides and Akkermansia, as well as increased Faecalibacterium. The relative abundance of Akkermansia was negatively associated with blood glucose levels, and the relative abundance of Faecalibacterium was positively related to inflammatory factor concentrations. The transfer of fecal microbiota from GDM and non-GDM donors to GF mice resulted in different gut microbiota colonization patterns, and hyperglycemia was induced in mice that received GDM donor microbiota. These results suggested that the shifting pattern of gut microbiota in GDM patients contributed to disease pathogenesis.
This study aimed to identify clinical features for prognosing mortality risk using machine-learning methods in patients with coronavirus disease 2019 (COVID-19). A retrospective study of the inpatients with COVID-19 admitted from 15 January to 15 March 2020 in Wuhan is reported. The data of symptoms, comorbidity, demographic, vital sign, CT scans results and laboratory test results on admission were collected. Machine-learning methods (Random Forest and XGboost) were used to rank clinical features for mortality risk. Multivariate logistic regression models were applied to identify clinical features with statistical significance. The predictors of mortality were lactate dehydrogenase (LDH), C-reactive protein (CRP) and age based on 500 bootstrapped samples. A multivariate logistic regression model was formed to predict mortality 292 in-sample patients with area under the receiver operating characteristics (AUROC) of 0.9521, which was better than CURB-65 (AUROC of 0.8501) and the machine-learning-based model (AUROC of 0.4530). An out-sample data set of 13 patients was further tested to show our model (AUROC of 0.6061) was also better than CURB-65 (AUROC of 0.4608) and the machine-learning-based model (AUROC of 0.2292). LDH, CRP and age can be used to identify severe patients with COVID-19 on hospital admission.
Cardiac fibroma is a rare benign primary tumour of the heart. In the paediatric population, it has been reported as the second most common benign cardiac tumour following rhabdomyoma. However, the prevalence of cardiac fibroma is rarely reported in the adult population. Signs and symptoms are nonspecific, including palpitations, cardiac murmur, arrhythmias, dyspnoea, cyanosis, chest pain, and sudden mortality, whereas, a number of patients with cardiac fibroma are asymptomatic. Surgical resection should be considered as the best option in symptomatic patients. This study reported four surgical cases of adults with cardiac fibroma arising from the left ventricle and a literature review regarding the clinical and pathological features, diagnostic modalities, therapeutic aspects, and prognosis of this rare entity.
Isolated congenital tricuspid regurgitation other than Ebstein’s anomaly was rare especially for children. The objective of this study was to investigate the clinical characteristics and to assess the results of tricuspid valvuloplasty for children with isolated tricuspid regurgitation.
From January 2010 to June 2019, 10 consecutive patients with isolated tricuspid regurgitation who were unresponsive to drug therapy underwent tricuspid valvuloplasty in our hospital. Patients’ clinical data were analysed retrospectively.
Mean age at operation was 48.5 ± 31.0 (range: 9–106) months and mean weight at operation was 16.1 ± 6.9 (range: 8.6–33.0) kg. All patients presented severe isolated tricuspid regurgitation. According to pathological lesions, the main causes accounted for chordae tendinea rupture (3/10), leaflet cleft (2/10), mal-connected chordal tendinea to leaflets (2/10), elongated chordae (1/10) and chordae absent (1/10), and severe anterior leaflet dysplasia (1/10). Individualised tricuspid valvuloplasty was adapted to all of them successfully. Post-operative echocardiography showed no tricuspid regurgitation in two patients and mild regurgitation in eight patients. The cardiothoracic ratios on their chest roentgenograms decreased from 0.59 ± 0.05 to 0.54 ± 0.05. At the latest follow-up (50.4 ± 47.2 months), echocardiography showed that mild to moderate tricuspid regurgitation in seven patients, moderate tricuspid regurgitation in three patients, and no patient with severe tricuspid regurgitation. All patients were in NYHA functional class I.
For patients with isolated tricuspid regurgitation who were not well responsive to drug therapy, individualised tricuspid valve repair can achieve an excellent result.
The COVID-19 outbreak required the significantly increased working time and intensity for health professionals in China, which may cause stress signs.
From March 2–13 of 2020, 4,618 health professionals in China were included in an anonymous, self-rated online survey regarding their concerns on exposure to the COVID-19 outbreak. The questionnaires consisted of five parts: basic demographic information and epidemiological exposure; occupational and psychological impact; concerns during the episode; coping strategies; and the Huaxi Emotional-Distress Index (HEI).
About 24.2% of respondents experienced high levels of anxiety or/and depressive symptoms since the COVID-19 outbreak. Respondents who worried about their physical health and those who had COVID-19 infected friends or close relatives were more likely to have high HEI levels, than those without these characteristics. Further, family relationship was found to have an independent protective effect against high HEI levels. Their main concerns were that their families would not be cared for and that they would not be able to work properly. Compared to respondents with clear emotional problems, those with somewhat hidden emotional issues adopted more positive coping measures.
About a quarter of medical staff experienced psychological problems during the pandemic of COVID-19. The psychological impact of stressful events was related to worrying about their physical health, having close COVID-19 infected acquaintances and family relationship issues. Therefore, the psychological supprot for medical staff fighting in the COVID-19 pandemic may be needed.
This paper presents a soft robot which can imitate the crawling locomotion of an earthworm. Locomotion of the robot can be achieved by expanding and contracting the body that is made of flexible material. A link of the earthworm-like robot is combined with three modules, and a multi-cavity earthworm-like soft robot is combined with multiple links. The multiple links of the earthworm-like soft robot are fabricated by silicone in the three-dimensional printed customized molds. Experiments on a single module, two-links, and three-links show that the soft robot can move and bend on condition of modules extension and contraction in a specified gait. The development of the earthworm-like soft robot shows a great prospect in many complicated environments such as pipeline detection.
Employing atomic-scale simulations, the response of a high-angle grain boundary (GB), the soft/hard GB, against external loading was systematically investigated. Under tensile loading close to the hard orientation, strain-induced dynamic recrystallization was observed to initiate through direct soft-to-hard grain reorientation, which was triggered by stress mismatch, inhibited by surface tension from the soft-hard GB, and proceeded by interface ledges. Such grain reorientation corresponds with expansion and contraction of the hard grain along and perpendicular to the loading direction, respectively, accompanied by local atomic shuffling, providing relatively large normal strain of 8.3% with activation energy of 0.04 eV per atom. Tensile strain and residual dislocations on the hard/soft GB facilitate the initiation of dynamic recrystallization by lowering the energy barrier and the critical stress for grain reorientation, respectively.
Laser-induced acoustic desorption (LIAD) enables the desorption of nonvolatile and/or thermally labile neutral compounds, such as asphaltenes, saturated hydrocarbons in base-oil fractions and biomolecules, from a metal surface into a mass spectrometer. This is a “gentle” evaporation technique and causes minimal fragmentation to the desorbed neutral molecules, including oligonucleotides and polypeptides. LIAD can be coupled with a wide range of ionization methods to facilitate analysis of the desorbed analytes by using many different types of mass spectrometers, including Fourier transform ion cyclotron resonance, linear quadrupole ion trap and quadrupole time-of-flight instruments. The development and improvement of LIAD remains an active research area with diverse goals such as better desorption efficiencies, minimized analyte fragmentation and greater versatility. This article details the theory, experimental methods, applications, and future directions of LIAD in combination with mass spectrometry.
Imprinted genes uniquely drive and support fetoplacental growth by controlling the allocation of maternal resources to the fetus and affecting the newborn’s growth. We previously showed that alterations of the placental imprinted gene expression are associated with suboptimal perinatal growth and respond to environmental stimuli including socio-economic determinants. At the same time, maternal psychosocial stress during pregnancy (MPSP) has been shown to affect fetal growth. Here, we set out to test the hypothesis that placental imprinted gene expression mediates the effects of MPSP on fetal growth in a well-characterized birth cohort, the Stress in Pregnancy (SIP) Study. We observed that mothers experiencing high MPSP deliver infants with lower birthweight (P=0.047). Among the 109 imprinted genes tested, we detected panels of placental imprinted gene expression of 23 imprinted genes associated with MPSP and 26 with birthweight. Among these genes, five imprinted genes (CPXM2, glucosidase alpha acid (GAA), GPR1, SH3 and multiple ankyrin repeat domains 2 (SHANK2) and THSD7A) were common to the two panels. In multivariate analyses, controlling for maternal age and education and gestational age at birth and infant gender, two genes, GAA and SHANK2, each showed a 22% mediation of MPSP on fetal growth. These data provide new insights into the role that imprinted genes play in translating the maternal stress message into a fetoplacental growth pattern.
There is little investigation on the interaction effects of adverse childhood experiences (ACEs) and social support on non-suicidal self-injury (NSSI), suicidal ideation and suicide attempt in community adolescent populations, or gender differences in these effects.
To examine the individual and interaction effects of ACEs and social support on NSSI, suicidal ideation and suicide attempt in adolescents, and explore gender differences.
A school-based health survey was conducted in three provinces in China between 2013–2014. A total of 14 820 students aged 10–20 years completed standard questionnaires, to record details of ACEs, social support, NSSI, suicidal ideation and suicide attempt.
Of included participants, 89.4% reported one or more category of ACEs. The 12-month prevalence of NSSI, suicidal ideation and suicide attempt was 26.1%, 17.5% and 4.4%, respectively; all were significantly associated with increased ACEs and lower social support. The multiple adjusted odds ratio of NSSI in low versus high social support was 2.27 (95% CI 1.85–2.67) for girls and 1.81 (95% CI 1.53–2.14) for boys, and their ratio (Ratio of two odds ratios, ROR) was 1.25 (P = 0.037). Girls with high ACEs scores (5–6) and moderate or low social support also had a higher risk of suicide attempt than boys (RORs: 2.34, 1.84 and 2.02, respectively; all P < 0.05).
ACEs and low social support are associated with increased risk of NSSI and suicidality in Chinese adolescents. Strategies to improve social support, particularly among female adolescents with a high number of ACEs, should be an integral component of targeted mental health interventions.
Kevlar (polyparaphenylene terephthalamide) and PBDT (poly(2,2′-disulfonyl-4,4′-benzidine terephthalamide))-derivatives have very similar chemical structures with aromatic rings. In this study, thermal conductivities of their single chains were calculated using molecular dynamics simulations. Chain rotation was found to be the key to reducing the thermal conductivity. By introducing a new chain rotation factor (CRF), we can easily quantify chain rotation level of single-chain polymers. We demonstrated that thermal conductivity decreases as the CRF increases. We performed further calculations on phonon properties and unveiled that the small thermal conductivity led by large chain rotation can be attributed to reduced phonon group velocities and shortened phonon mean free paths. Insights obtained in this study can be used for tuning thermal conductivity of various polymers and facilitating their various applications including thermal energy conversion and management.
Given the global water challenges, solar-driven steam generation has become a renewed topic recently as an energy-efficient way for clean water production. Here, a hybrid plasmonic structure consisting of a top layer of TiN nanoparticles (NPs) and a bottom layer of mesoporous anodized alumina membrane (AAM) was rationally designed and fabricated. The top TiN NPs with broadband light absorption acted as a plasmonic heating layer, which converted the absorbed light to heat efficiently for interfacial water heating. The AAM acted as the mechanical support layer, guaranteeing the heat isolation and continuous water replenishment. With optimized thickness of the TiN top layer, a solar steam generation efficiency of 87.7% was achieved in this study. This efficiency is comparable or even higher than prior studies. The current work proves the capability of the TiN NPs as an alternative photothermal material.
Coherent cuboidal B2 nanoprecipitation in body-centered cubic (BCC)-based high-entropy alloys (HEAs) is important for the improvement of mechanical strength. The present work primarily investigated the effect of Ti substitution for Al on the cuboidal B2 nanoprecipitates in BCC Al0.7NiCoFeCr2 HEAs. A series of (Al,Ti)0.7NiCoFeCr2 HEAs with different Al/Ti ratios were prepared by suction-cast processing, and their microstructures and mechanical properties were then characterized comprehensively. It was found that the substitution of Ti for Al can change the phase structures of ordered precipitation, from the B2-AlNi to a highly ordered L21-Ni2AlTi phase. Especially, a small amount addition of Ti (≤4.2 at.%, Al/Ti ratio ≥2/1) renders the HEAs with cuboidal L21 nanoparticles coherently precipitated into the BCC matrix, which is attributed to the moderate lattice misfit (ε = 0.5–0.6%) between BCC and L21 phases. HEAs with such coherent microstructures exhibit high compressive yield strength of about 1700–1800 MPa. When the Ti content reaches up to 6.25 at.%, the matrix of the alloy will be turned into the σ phase, rather than BCC, leading to a heavy brittleness.
Transition metal dichalcogenides (TMDC), such as MoS2, WS2 have attracted attention due to their mechanical and electronic properties in their two dimensional (2D) structures. Here, we report a facile growth of monolayer TMDC using oxide source materials with the assistant of NaCl. The addition of NaCl can enhance the lateral growth and widen the growth window of TMDC. Through carefully controlling the growth parameters, large area growth of TMDC can be achieved. Two steps E-beam lithography was utilized to fabricate electrodes of TMDC. The phototransistors made from the CVD grown TMDC show strong persistent photoconductivity (PPC). It was finally shown that TMDC device capping with h-BN could have suppressed PPC effects.
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.
We report on a target system supporting automated positioning of nano-targets with a precision resolution of
in three dimensions. It relies on a confocal distance sensor and a microscope. The system has been commissioned to position nanometer targets with 1 Hz repetition rate. Integrating our prototype into the table-top ATLAS 300 TW-laser system at the Laboratory for Extreme Photonics in Garching, we demonstrate the operation of a 0.5 Hz laser-driven proton source with a shot-to-shot variation of the maximum energy about 27% for a level of confidence of 0.95. The reason of laser shooting experiments operated at 0.5 Hz rather than 1 Hz is because the synchronization between the nano-foil target positioning system and the laser trigger needs to improve.
Nanosecond pulse discharges can provide high reduced electric field for exciting high-energy electrons, and the ultrafast rising time of the applied pulse can effectively suppress the generation of spark streamer and produce homogeneous discharges preionized by runaway electrons in atmospheric-pressure air. In this paper, the electrostatic field in a tube-plate electrodes gap is calculated using a calculation software. Furthermore, a simple physical model of nanosecond pulse discharges is established to investigate the behavior of the runaway electrons during the nanosecond pulse discharges with a rise time of 1.6 ns and a full-width at half-maximum of 3–5 ns in air. The physical model is coded by a numerical software, and then the runaway electrons and electron avalanche are investigated under different conditions. The simulated results show that the applied voltage, voltage polarity, and gas pressure can significantly affect the formation of the avalanche and the behavior of the runaway electrons. The inception time of runaway breakdown decreases when the applied voltage increases. In addition, the threshold voltage of runaway breakdown has a minimum value (10 kPa) with the variation of gas pressure.
A compact dual-frequency antenna with enhanced bandwidth is proposed in this paper. Dual-frequency operation is realized by cutting a slot in the elliptical patch, and bandwidth enhancement is achieved by using a partial ground plane. Compared with the conventional half-wave antenna, the antenna has a compact size of 24 × 20 mm2, which equals to 0.38 λ1 × 0.31 λ1 (λ1, the guided wavelength at the first resonant frequency). The dual-frequency antenna with a partial rectangle ground and a partial arc-shaped ground is investigated for impedance matching. Simulated results indicate that the antenna with a partial arc-shaped ground can obtain a larger bandwidth for two bands than that with a partial rectangle ground. Experimental results show that the antenna with a partial arc-shaped ground can operate in 2.4 and 5 GHz bands, which covers the 2.4, 5.2 and 5.8 GHz for wireless local area network. The impedance bandwidths of two bands are 9.5 and 13.6%, respectively. Also, good radiation performances have been achieved at two bands.