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Electronic skin (e-skin) is playing an increasingly important role in health detection, robotic teleoperation, and human-machine interaction, but most e-skins currently lack the integration of on-site signal acquisition and transmission modules. In this paper, we develop a novel flexible wearable e-skin sensing system with 11 sensing channels for robotic teleoperation. The designed sensing system is mainly composed of three components: e-skin sensor, customized flexible printed circuit (FPC), and human-machine interface. The e-skin sensor has 10 stretchable resistors distributed at the proximal and metacarpal joints of each finger respectively and 1 stretchable resistor distributed at the purlicue. The e-skin sensor can be attached to the opisthenar, and thanks to its stretchability, the sensor can detect the bent angle of the finger. The customized FPC, with WiFi module, wirelessly transmits the signal to the terminal device with human-machine interface, and we design a graphical user interface based on the Qt framework for real-time signal acquisition, storage, and display. Based on this developed e-skin system and self-developed robotic multi-fingered hand, we conduct gesture recognition and robotic multi-fingered teleoperation experiments using deep learning techniques and obtain a recognition accuracy of 91.22%. The results demonstrate that the developed e-skin sensing system has great potential in human-machine interaction.
Since embryonic stem cells (ESCs) were first identified, significant progress has been achieved. However, the establishment of buffalo ESCs (bESCs) is still unclear. This study was undertaken to explore the effect of the blastocyst stage on the isolation of bESCs. Firstly, our results indicated that the pluripotent genes were mainly expressed at the early stages of blastocyst, and the attachment and colony formation rates of bESCs derived from expanded blastocyst and hatched blastocyst were significantly higher than early blastocyst and blastocyst. In the meantime, bESCs showed positive alkaline phosphatase activity and expressed genes like OCT4, NANOG, SOX2, c-MYC, CDH1, KLF4, and TBX3. Immunofluorescence also confirmed the expression of OCT4, SOX2. Embryoid bodies expressing three marker genes were generated from the differentiation experiment, and fibroblast, epithelial, and neuron-like cells were induced. Moreover, naive-related genes KLF4, TBX3, primed-related genes FGF5, ACTA2 were expressed in the cells, but not REX-1. Immunofluorescence and western blot confirmed the FGF5 expression. Furthermore, bESCs could maintain pluripotency with the signal of LIF and bFGF. In summary, our results indicated that expanded blastocyst and hatched blastocyst are more suitable for bESCs isolation.
The southern Great Xing’an Range (SGXR), located in the eastern segment of the Central Asian Orogenic Belt (CAOB), is one of the most economically important Cu–Mo–Fe–Sn–Pb–Zn–Ag metallogenic provinces in China. The newly discovered Panjiaduan Cu–Pb–Zn deposit (9.3 Mt; at 1.36% Cu, 2.90% Pb, 3.80% Zn and 38.12 g/t Ag), located in the SE segment of the SGXR, is primarily hosted in fracture zones in volcanic rocks and granodiorite of the Manitu Formation. Four paragenetic stages of metallic mineralization are identified: (I) quartz-pyrite-arsenopyrite; (II) quartz-polymetallic sulphide; (III) quartz-galena-sphalerite-argentite; and (IV) quartz-calcite-minor sulphide. The hydrothermal quartz contains three types of primary fluid inclusion (FIs): vapour-rich two-phase liquid-vapour (LV-type), liquid-rich two-phase liquid-vapour (VL-type) and three-phase liquid-vapour-solid FIs (SL-type). Stages I and II contain all types with homogenization temperatures (Th) of 324–386 °C and 276–334 °C as well as salinities of 0.7–38.0 wt% and 0.9–34.7 wt%, respectively, whereas stage III is composed of VL- and LV-type FIs with Th of 210–269 °C and salinities of 0.5–7.2 wt%. Only VL-type FIs occur in stage IV, with Th of 139–185 °C and salinities of 1.6–4.2 wt%. The δ18OH2O and δD values vary from −15.7 to 2.6‰ and −132.7 to −110.2‰, respectively, indicating predominant meteoric water with an initial magmatic source. The He–Ar isotopic compositions of the pyrite inclusions from the Panjiaduan Cu–Pb–Zn veins suggest that fluids were derived from the crust.
Trypanosoma musculi is a, globally distributed, mouse-specific haemoflagellate, of the family Trypanosomatidae, which shares similar characteristics in morphology with Trypanosoma lewisi. The kinetoplast (mitochondrial) DNA of Trypanosomatidae flagellates is comprised of catenated maxicircles and minicircles. However, genetic information on the T. musculi kinetoplast remains largely unknown. In this study, the T. musculi maxicircle genome was completely assembled, with PacBio and Illumina sequencing, and the size was confirmed at 34 606 bp. It consisted of 2 distinct parts: the coding region and the divergent regions (DRs, DRI and II). In comparison with other trypanosome maxicircles (Trypanosoma brucei, Trypanosoma cruzi and T. lewisi), the T. musculi maxicircle has a syntenic distribution of genes and shares 73.9, 78.0 and 92.7% sequence identity, respectively, over the whole coding region. Moreover, novel insertions in MURF2 (630 bp) and in ND5 (1278 bp) were found, respectively, which are homologous to minicircles. These findings support an evolutionary scenario similar to the one proposed for insertions in Trypanosoma cruzi, the pathogen of American trypanosomiasis. These novel insertions, together with a deletion (281 bp) in ND4, question the role of Complex I in T. musculi. A detailed analysis of DRII indicated that it contains numerous repeat motifs and palindromes, the latter of which are highly conservative and contain A5C elements. The comprehensively annotated kinetoplast maxicircle of T. musculi reveals a high degree of similarity between this parasite and the maxicircle of T. lewisi and suggests that the DRII could be a valuable marker for distinguishing these evolutionarily related species.
This study aimed to investigate the organization, workload, and psychological impact of COVID-19 on healthcare workers from the domestic Medical Aid Teams (MATs) sent to Wuhan in China.
Leaders and members of MATs involved in the care for COVID-19 patients were invited to participate in a study by completing 2 separate self-report questionnaires from April 1 to 24, 2020.
A total of 9 MAT leaders were involved and 464 valid questionnaires were collected from 140 doctors and 324 nurses. Mean age of the doctors and nurses were 39.34 ± 6.70 (26∼58 years old) and 31.88 ± 5.29 (21∼52 years old), with 72 (15.5%) being males. Nurses were identified as an independent risk factor (HR 1.898; P = 0.001) for a day working time in the multivariate analysis. The proportions of psychological consulting received among nurses were higher than those among doctors (49.7 vs 30.0%, P < 0.001). More than 50% of the anesthetists and emergency doctors who have received psychological consulting thought that it was effective according to self-evaluation.
This study focused on healthcare workers’ situation during the early period of the pandemic. Nurses worked longer than doctors. The effectiveness of psychological consulting depends on the physicians’ specialties and the working conditions of the nurses and psychological consulting targeting different specialties need to be improved.
This study evaluated the association between inflammatory diets as measured by the Dietary Inflammatory index (DII), inflammation biomarkers and the development of preeclampsia among the Chinese population. We followed the reporting guidelines of the Strengthening the Reporting of Observational Studies in Epidemiology statement for observational studies. A total of 466 preeclampsia cases aged over 18 years were recruited between March 2016 and June 2019, and 466 healthy controls were 1:1 ratio matched by age (±3 years), week of gestation (±1 week) and gestational diabetes mellitus. The energy-adjusted DII (E-DII) was computed based on dietary intake assessed using a seventy-nine item semiquantitative FFQ. Inflammatory biomarkers were analysed by ELISA kits. The mean E-DII scores were −0·65 ± 1·58 for cases and −1·19 ± 1·47 for controls (P value < 0·001). E-DII scores positively correlated with interferon-γ (rs = 0·194, P value = 0·001) and IL-4 (rs = 0·135, P value = 0·021). After multivariable adjustment, E-DII scores were positively related to preeclampsia risk (Ptrend < 0·001). The highest tertile of E-DII was 2·18 times the lowest tertiles (95 % CI = 1·52, 3·13). The odds of preeclampsia increased by 30 % (95 % CI = 18 %, 43 %, P value < 0·001) for each E-DII score increase. The preeclampsia risk was positively associated with IL-2 (OR = 1·07, 95 % CI = 1·03, 1·11), IL-4 (OR = 1·26, 95 % CI = 1·03, 1·54) and transforming growth factor beta (TGF-β) (OR = 1·17, 95 % CI = 1·06, 1·29). Therefore, proinflammatory diets, corresponding to higher IL-2, IL-4 and TGF-β levels, were associated with increased preeclampsia risk.
We have grown intermetallic ErPd2Si2 single crystals employing laser diodes with the floating-zone method. The temperature dependence of the unit-cell parameters was determined using synchrotron and in-house X-ray powder diffraction measurements from 20 to 500 K. The diffraction patterns fit well with the tetragonal I4/mmm space group (No. 139) with two chemical formulae within the unit cell. The synchrotron powder diffraction study shows that the refined unit-cell parameters are a = 4.10320(2) Å, c = 9.88393(5) Å at 298 K and a = 4.11737(2) Å, c = 9.88143(5) Å at 500 K, resulting in the unit-cell volume V = 166.408(1) Å3 (298 K) and 167.517(2) Å3 (500 K). In the whole studied temperature range, no structural phase transition was observed. Upon cooling, the unit-cell parameters a and c are shortened and elongated, respectively.
As a result of the COVID-19 pandemic, whether and when the world can reach herd immunity and return to normal life and a strategy for accelerating vaccination programmes constitute major concerns. We employed Metropolis–Hastings sampling and an epidemic model to design experiments based on the current vaccinations administered and a more equitable vaccine allocation scenario. The results show that most high-income countries can reach herd immunity in less than 1 year, whereas low-income countries should reach this state after more than 3 years. With a more equitable vaccine allocation strategy, global herd immunity can be reached in 2021. However, the spread of SARS-CoV-2 variants means that an additional 83 days will be needed to reach global herd immunity and that the number of cumulative cases will increase by 113.37% in 2021. With the more equitable vaccine allocation scenario, the number of cumulative cases will increase by only 5.70% without additional vaccine doses. As SARS-CoV-2 variants arise, herd immunity could be delayed to the point that a return to normal life is theoretically impossible in 2021. Nevertheless, a more equitable global vaccine allocation strategy, such as providing rapid vaccine assistance to low-income countries/regions, can improve the prevention of COVID-19 infection even though the virus could mutate.
Metabolically healthy obesity (MHO) might be an alternative valuable target in obesity treatment. We aimed to assess whether alternative Mediterranean (aMED) diet and Dietary Approaches to Stop Hypertension (DASH) diet were favourably associated with obesity and MHO phenotype in a Chinese multi-ethnic population. We conducted this cross-sectional analysis using the baseline data of the China Multi-Ethnic Cohort study that enrolled 99 556 participants from seven diverse ethnic groups. Participants with self-reported cardiometabolic diseases were excluded to eliminate possible reverse causality. Marginal structural logistic models were used to estimate the associations, with confounders determined by directed acyclic graph (DAG). Among 65 699 included participants, 11·2 % were with obesity. MHO phenotype was present in 5·7 % of total population and 52·7 % of population with obesity. Compared with the lowest quintile, the highest quintile of DASH diet score had 23 % decreased odds of obesity (OR = 0·77, 95 % CI 0·71, 0·83, Ptrend < 0·001) and 27 % increased odds of MHO (OR = 1·27, 95 % CI 1·10, 1·48, Ptrend = 0·001) in population with obesity. However, aMED diet showed no obvious favourable associations. Further adjusting for BMI did not change the associations between diet scores and MHO. Results were robust to various sensitivity analyses. In conclusion, DASH diet rather than aMED diet is associated with reduced risk of obesity and presents BMI-independent metabolic benefits in this large population-based study. Recommendation for adhering to DASH diet may benefit the prevention of obesity and related metabolic disorders in Chinese population.
Conventional unpowered lower limb exoskeleton paid little attention to the metabolic cost of body during sit down (SD)/stand up (SU). The SD motion model and the motion characteristics of lower extremity are analyzed; then, a novel unpowered lower limb exoskeleton is proposed, and the contribution degree of muscles and stiffness of joints are used for determining the location and stiffness of energy storage element. The metabolic cost of relevant muscles in joints of the left leg is obtained based on Opensim software. The results show that metabolic cost of the gracilis, rectus femoris (RF), and long head of the biceps femoris decreased about 13%, 9%, and 68%, respectively. The total metabolic cost of body decreased about 14% during SD. However, the metabolic cost of the gracilis, RF, and long/short head of the biceps femoris increased about 22%, 33%, 208%, and 46%, respectively. And the metabolic cost of sartorius reduces about 39%, the total metabolic cost of body increased about 25.6% during SU, under the exoskeleton conditions. The results of this study can provide a theoretical basis for the optimal design of unpowered lower limb exoskeleton.
To investigate the association between the Metabolic Score for Visceral Fat (METS-VF) and risk of type 2 diabetes mellitus (T2DM) and compare the predictive value of the METS-VF for T2DM incidence with other obesity indices in Chinese people. A total of 12 237 non-T2DM participants aged over 18 years from the Rural Chinese Cohort Study of 2007–2008 were included at baseline and followed up during 2013–2014. The cox proportional hazards regression was used to calculate hazard ratios (HR) and 95 % CI for the association between baseline METS-VF and T2DM risk. Restricted cubic splines were used to model the association between METS-VF and T2DM risk. Area under the receiver operating characteristic curve (AUC) analysis was used to evaluate the ability of METS-VF to predict T2DM incidence. During a median follow-up of 6·01 (95 % CI 5·09, 6·06) years, 837 cases developed T2DM. After adjusting for potential confounding factors, the adjusted HR for the highest v. lowest METS-VF quartile was 5·97 (95 % CI 4·28, 8·32), with a per 1-sd increase in METS-VF positively associated with T2DM risk. Positive associations were also found in the sensitivity and subgroup analyses, respectively. A significant nonlinear dose–response association was observed between METS-VF and T2DM risk for all participants (Pnonlinearity = 0·0347). Finally, the AUC value of METS-VF for predicting T2DM was largest among six indices. The METS-VF may be a reliable and applicable predictor of T2DM incidence in Chinese people regardless of sex, age or BMI.
The effect of vitamin D (VD) on the risk of preeclampsia (PE) is uncertain. Few of previous studies focused on the relationship between dietary VD intake and PE risk. Therefore, we conducted this 1:1 matched case–control study to explore the association of dietary VD intake and serum VD concentrations with PE risk in Chinese pregnant women. A total of 440 pairs of participants were recruited during March 2016 to June 2019. Dietary information was obtained using a seventy-eight-item semi-quantitative FFQ. Serum concentrations of 25(OH)D2 and 25(OH)D3 were measured by liquid chromatography–tandem MS. Multivariate conditional logistic regression was used to estimate OR and 95 % CI. Restricted cubic splines (RCS) were plotted to evaluate the dose–response relationship of dietary VD intake and serum VD concentrations with PE risk. Compared with the lowest quartile, the OR of the highest quartile were 0·45 (95 % CI 0·29, 0·71, Ptrend = 0·001) for VD dietary intake and 0·26 (95 % CI 0·11, 0·60, Ptrend = 0·003) for serum levels after adjusting for confounders. In addition, the RCS analysis suggested a reverse J-shaped relationship between dietary VD intake and PE risk (P-nonlinearity = 0·02). A similar association was also found between serum concentrations of total 25(OH)D and PE risk (P-nonlinearity = 0·02). In conclusion, this study provides evidence that higher dietary intake and serum levels of VD are associated with the lower risk of PE in Chinese pregnant women.
The present study evaluated effects of dietary supplementation with tryptophan (Trp) on muscle growth, protein synthesis and antioxidant capacity in hybrid catfish Pelteobagrus vachelli♀ × Leiocassis longirostris♂. Fish were fed six different diets containing 2·6 (control), 3·1, 3·7, 4·2, 4·7 and 5·6 g Trp/kg diet for 56 d, respectively. Results showed that dietary Trp significantly (1) improved muscle protein content, fibre density and frequency of fibre diameter; (2) up-regulated the mRNA levels of PCNA, myf5, MyoD1, MyoG, MRF4, IGF-I, IGF-II, IGF-IR, PIK3Ca, TOR, 4EBP1 and S6K1; (3) increased phosphorylation levels of AKT, TOR and S6K1; (4) decreased contents of MDA and PC, and increased activities of CAT, GST, GR, ASA and AHR; (5) up-regulated mRNA levels of CuZnSOD, CAT, GST, GPx, GCLC and Nrf2, and decreased Keap1 mRNA level; (6) increased nuclear Nrf2 protein level and the intranuclear antioxidant response element-binding ability, and reduced Keap1 protein level. These results indicated that dietary Trp improved muscle growth, protein synthesis as well as antioxidant capacity, which might be partly related to myogenic regulatory factors, IGF/PIK3Ca/AKT/TOR and Keap1/Nrf2 signalling pathways. Finally, based on the quadratic regression analysis of muscle protein and MDA contents, the optimal Trp requirements of hybrid catfish (21·82–39·64 g) were estimated to be 3·94 and 3·93 g Trp/kg diet (9·57 and 9·54 g/kg of dietary protein), respectively.
In minimally invasive surgery, surgical instruments with a wrist joint have better flexibility. However, the bending motion of the wrist joint causes a coupling motion between the end-effector and wrist joint, affecting the accuracy of the movement of the surgical instrument. Aiming at this problem, a new gear train decoupling method is proposed in the paper, which can automatically compensate for the coupled motion in real-time. Based on the performance tests of the instrument prototype, a series of decoupling effects tests are carried out. The test results show that the surgical instrument has excellent decoupling ability and stable performance.
A few former studies suggested that there are partial overlaps in abnormal brain structure and cognitive function between hypochondriasis (HS) and schizophrenia (SZ). But their differences in brain activity and cognitive function were unclear.
Twenty-one HS patients, 23 SZ patients, and 24 healthy controls (HC) underwent resting-state functional magnetic resonance imaging (rs-fMRI) with the regional homogeneity analysis (ReHo), subsequently exploring the relationship between ReHo value and cognitive functions. The support vector machines (SVM) were used on effectiveness evaluation of ReHo for differentiating HS from SZ.
Compared with HC, HS showed significantly increased ReHo values in right middle temporal gyrus (MTG), left inferior parietal lobe (IPL), and right fusiform gyrus (FG), while SZ showed increased ReHo in left insula, decreased ReHo values in right paracentral lobule. Additionally, HS showed significantly higher ReHo values in FG, MTG, and left paracentral lobule, but lower in insula than SZ. The higher ReHo values in insula were associated with worse performance in MATRICS consensus cognitive battery (MCCB) in HS group. SVM analysis showed a combination of the ReHo values in insula and FG was able to satisfactorily distinguish the HS and SZ patients.
Our results suggested that the altered default mode network (DMN), of which abnormal spontaneous neural activity occurs in multiple brain regions, might play a key role in the pathogenesis of HS, and the resting-state alterations of insula are closely related to cognitive dysfunction in HS. Furthermore, the combination of the ReHo in FG and insula was a relatively ideal indicator to distinguish HS from SZ.
Spoofing is a kind of deliberate interference that aims to manipulate global navigation satellite system (GNSS) receivers into counterfeit position solutions. Conventional anti-spoofing methods are implemented prior to the calculation of the position solution, depending on the specific spoofing attack mechanisms. The paper presents a spoofing detection and mitigation method implemented in the position domain. The proposed method projects the correlograms of the visible satellites to a position-clock bias domain to construct the position domain projected correlogram. P(Y) code signatures retrieved from a reference station receiver are used to identify the counterfeit position solution and remove it from the victim receiver. Compared with the conventional single-channel spoofing detection technique, the proposed anti-spoofing method is more robust against thermal noise by combining the energy from multiple satellites. Detailed mathematical derivation of the statistical characteristics of this method is presented. Its effectiveness is validated using a realistic dataset generated by a Spirent GNSS simulator and NordNav wideband front-end. Results show that the proposed algorithm is capable of not only detecting a spoofing attack but also removing the spoofing effect from the victim receiver.
Over recent decades, Chinese giant salamanders Andrias spp. have declined dramatically across much of their range. Overexploitation and habitat degradation have been widely cited as the cause of these declines. To investigate the relative contribution of each of these factors in driving the declines, we carried out standardized ecological and questionnaire surveys at 98 sites across the range of giant salamanders in China. We did not find any statistically significant differences between water parameters (temperature, dissolved oxygen, ammonia, nitrite, nitrate, salinity, alkalinity, hardness and flow rate) recorded at sites where giant salamanders were detected by survey teams and/or had been recently seen by local respondents, and sites where they were not detected and/or from which they had recently been extirpated. Additionally, we found direct and indirect evidence that the extraction of giant salamanders from the wild is ongoing, including within protected areas. Our results support the hypothesis that the decline of giant salamanders across China has been primarily driven by overexploitation. Data on water parameters may be informative for the establishment of conservation breeding programmes, an initiative recommended for the conservation of these species.
A multidisciplinary fieldwork and research project was recently begun at the Yangshang site (220–140 ka), a late Early Paleolithic locale in the western Chinese Loess Plateau. 1696 lithic artifacts and 337 faunal remains were recovered during the excavation. Sedimentological and paleoenvironmental investigations indicate the site preserves a relatively long and minimally disturbed archaeological sequence associated with paleoenvironmental changes during MIS 7–6. A detailed techno-typological analysis of Yangshang's lithic assemblages was undertaken to examine the influence of glacial cycles on late Middle Pleistocene hominin technological strategies in the western Chinese Loess Plateau. The results show that while the Yangshang site is dominated by quartz-based core/flake assemblages typical of most Early Paleolithic sites in North China, the lithic assemblages provide evidence that different provisioning systems existed during the penultimate glaciation. We argue that these shifts reflect changes in land use and mobility that were tied to climate change. Our results suggest that theoretically informed statistical analyses of so-called unchanging and crude lithic technology can yield meaningful evidence for behavioral shifts.