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Al-based composites with micrometer and submicro-TiB2 reinforcements (1 wt%) have been produced by selective laser melting (SLM) from mixed powder under different processing conditions. The results show that the densification level of SLM-processed composite with submicro-TiB2 particles (>99.0%) was 0.3–2.4% larger than that of micrometer TiB2-reinforced composite under the same processing conditions. The distribution of Si precipitates in the matrix experienced a transform from continuous cellular to directional line-like morphology with reinforcement size decreasing from micron to submicron. The reinforcement size added in the matrix also exhibited a critical influence on preferred orientation and grain size of matrix. The SLM-processed composites exhibited improved tensile strength and ductility with a decrease of reinforcement size. High tensile strength of ∼400 MPa and elongation of ∼3.6% were obtained for the fine TiB2-reinforced samples, increasing by 6 and 13% compared with that of micro-TiB2–added samples, respectively.
Schizophrenia is a serious health problem worldwide. This systematic analysis aims to quantify the burden of schizophrenia at the global, regional and national levels using the Global Burden of Disease Study 2017 (GBD 2017).
We collected detailed information on the number of incidence cases, disability-adjusted life years (DALYs) and age-standardised incidence rate (ASIR) and age-standardised rate of DALYs (ASDR) during 1990–2017 from GBD 2017. The estimated annual percentage changes (EAPCs) in the ASIR and in the ASDR were calculated to quantify the temporal trends in the ASIR and ASDR of schizophrenia.
Globally there were 1.13 million (95% uncertainty interval [UI] = 1.00 to 1.28) incident schizophrenia cases and 12.66 million (95% UI = 9.48 to 15.56) DALYs due to schizophrenia in 2017. The global ASIR decreased slightly from 1990 to 2017 (EAPC = −0.124, 95% UI = −0.114 to −0.135), while the ASDR was stable. The number of incident cases, DALYs, ASIR and ASDR were higher for males than for females. The incident rate and DALYs rate were highest among those aged 20–29 and 30–54 years, respectively. ASIR and ASDR were highest in East Asia in 2017, at 19.66 (95% UI = 17.72 to 22.00) and 205.23 (95% UI = 153.13 to 253.34), respectively. In 2017, the ASIR was highest in countries with a high-moderate sociodemographic index (SDI) and the ASDR was highest in high-SDI countries. We also found that the EAPC in ASDR was negatively correlated with the ASDR in 1990 (P = 0.001, ρ = −0.23).
The global burden of schizophrenia remains large and continues to increase, thereby increasing the burden on health-care systems. The reported findings should be useful for resource allocation and health services planning for the increasing numbers of patients with schizophrenia in ageing societies.
Octapyrgites elongatus n. gen. n. sp., a relatively rare, tetraradial olivooid (Cnidaria, Medusozoa), is described from Bed 5 of the Yanjiahe Formation (Cambrian Stage 2) near Yichang, China. Although similar to Olivooides and Quadrapyrgites from the Fortunian Stage in consisting of a partially corrugated (longitudinal) periderm with a quadrate (transverse) apical portion and V-shaped apertural lobes, O. elongatus is substantially larger than other olivooids. The elongate apical region of O. elongatus is similar to four-sided Anaconularia anomala (Barrande, 1867), though with a flat tip that may have been an adaption for a sessile mode of life. As in other olivooids, embryonic development in O. elongatus may have been direct. Last, the paucity of olivooids and the absence of pentaradial cnidarians and carinachitids in Cambrian Stage 2 indicate a marked decline in the disparity of cnidarians near the Fortunian–Cambrian Age 2 boundary, when by contrast bilaterians underwent rapid diversification.
To evaluate the effects of gestational weight gain (GWG) in the first trimester (GWG-F) and the rate of gestational weight gain in the second trimester (RGWG-S) on gestational diabetes mellitus (GDM), exploring the optimal GWG ranges for the avoidance of GDM in Chinese women.
A population-based prospective study was conducted. Gestational weight was measured regularly in every antenatal visit and assessed by the Institute of Medicine (IOM) criteria (2009). GDM was assessed with the 75-g, 2-h oral glucose tolerance test at 24–28 weeks of gestation. Multivariable logistic regression was performed to assess the effects of GWG-F and RGWG-S on GDM, stratified by pre-pregnancy BMI. In each BMI category, the GWG values corresponding to the lowest prevalence of GDM were defined as the optimal GWG range.
Pregnant women (n 1910) in 2017.
After adjusting for confounders, GWG-F above IOM recommendations increased the risk of GDM (OR; 95 % CI) among underweight (2·500; 1·106, 5·655), normal-weight (1·396; 1·023, 1·906) and overweight/obese women (3·017; 1·118, 8·138) compared with women within IOM recommendations. No significant difference was observed between RGWG-S and GDM (P > 0·05) after adjusting for GWG-F based on the previous model. The optimal GWG-F ranges for the avoidance of GDM were 0·8–1·2, 0·8–1·2 and 0·35–0·70 kg for underweight, normal-weight and overweight/obese women, respectively.
Excessive GWG in the first trimester, rather than the second trimester, is associated with increased risk of GDM regardless of pre-pregnancy BMI. Obstetricians should provide more pre-emptive guidance in achieving adequate GWG-F.
Metabolically healthy obesity refers to a subset of obese people with a normal metabolic profile. We aimed to explore the association between metabolically healthy and obesity status and risk of hypertension among Chinese adults from The Rural Chinese Cohort Study. This prospective cohort study enrolled 9137 Chinese adults without hypertension, type 2 diabetes, or treatment for lipid abnormality at baseline (2007-2008) and followed up during 2013-2014. Modified Poisson regression models were used to examine the risk of hypertension by different metabolically healthy and obesity status, estimating relative risks (RRs) and 95% confidence intervals (CIs). During 6 years of follow-up, we identified 1734 new hypertension cases (721 men). After adjusting for age, sex, smoking, and other confounding factors, risk of hypertension was increased with metabolically healthy general obesity (MHGO) defined by body mass index (RR 1.75, 95% CI 1.02–3.00) and metabolically healthy abdominal obesity (MHAO) defined by waist circumference (RR 1.51, 95% CI 1.12–2.04) as compared with metabolically healthy non-obesity. The associations between metabolically healthy and obesity status and hypertension outcome were consistent after stratifying by sex, age, smoking, alcohol drinking, and physical activity. Both MHGO and MHAO were associated with increased risk of hypertension. Obesity control programs should be implemented to prevent or delay the development of hypertension in rural China.
This study examined the activation of first language (L1) translations in second language (L2) word recognition in a lexical decision task. Test materials included English words that differed in the frequency of their Chinese translations or in their surface lexical frequency while other lexical properties were controlled. Chinese speakers of English as a second language of different proficiencies and native speakers of English were tested. Native speakers produced a reliable lexical frequency effect but no translation frequency effect. English as a second language speakers of lower English proficiency showed both a translation frequency effect and a lexical frequency effect, but those of higher English proficiency showed a lexical frequency effect only. The results were discussed in a verification model of L2 word recognition. According to the model, L2 word recognition entails a checking procedure in which activated L2 words are checked against their L1 translations. The two frequency effects are seen to have two different loci. The lexical frequency effect is associated with the initial activation of L2 lemmas, and the translation frequency effect arises in the verification process. Existing evidence for verification in L2 word recognition and new issues this model raises are discussed.
The microbiota–gut–brain axis, especially the microbial tryptophan (Trp) biosynthesis and metabolism pathway (MiTBamp), may play a critical role in the pathogenesis of major depressive disorder (MDD). However, studies on the MiTBamp in MDD are lacking. The aim of the present study was to analyze the gut microbiota composition and the MiTBamp in MDD patients.
We performed shotgun metagenomic sequencing of stool samples from 26 MDD patients and 29 healthy controls (HCs). In addition to the microbiota community and the MiTBamp analyses, we also built a classification based on the Random Forests (RF) and Boruta algorithm to identify the gut microbiota as biomarkers for MDD.
The Bacteroidetes abundance was strongly reduced whereas that of Actinobacteria was significantly increased in the MDD patients compared with the abundance in the HCs. Most noteworthy, the MDD patients had increased levels of Bifidobacterium, which is commonly used as a probiotic. Four Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologies (KOs) (K01817, K11358, K01626, K01667) abundances in the MiTBamp were significantly lower in the MDD group. Furthermore, we found a negative correlation between the K01626 abundance and the HAMD scores in the MDD group. Finally, RF classification at the genus level can achieve an area under the receiver operating characteristic curve of 0.890.
The present findings enabled a better understanding of the changes in gut microbiota and the related Trp pathway in MDD. Alterations of the gut microbiota may have the potential as biomarkers for distinguishing MDD patients form HCs.
It is urgent to develop new antimalarial drugs with good therapeutic effects to address the emergence of drug resistance. Here, the artelinic acid-choline derivative (AD) was synthesized by dehydration reaction and esterification reaction, aimed to avoid the emergence of drug resistance by synergistic effect of artemisinins and choline derivative, which could compete with choline for rate-limiting enzymes in the phosphatidylcholine (PC) biosynthetic pathway. AD was formulated into liposomes (ADLs) by the thin-film hydration method. Efficacy of ADLs was evaluated by Peters 4-day suppression test. The suppression percentage against Plasmodium yoelii BY265 (PyBY265) in ADLs group was higher than those of positive control groups (dihydroartemisinin liposomes, P < 0.05) and other control groups (P ⩽ 0.05) at the doses of 4.4, 8.8, 17.6 µmol (kg·d)−1, respectively. The negative conversion fraction, recrudescence fraction and survival fraction of ADLs group were superior to other control groups. Pharmacokinetics in rats after intravenous injection suggested that ADLs exhibited higher exposure levels (indexed by area under concentration-time curve) than that of AD solution, artelinic acid liposomes or artelinic acid solution (P < 0.01). Taken together, ADLs exhibited promising antimalarial efficacy and pharmacokinetic characteristics.
Above-threshold ionization (ATI) is one of the most fundamental processess when atoms or molecules are subjected to intense laser fields. Analysis of ATI process in intense laser fields by a Wigner-distribution-like (WDL) function is reviewed in this paper. The WDL function is used to obtain various time-related distributions, such as time-energy distribution, ionization time distribution, and time-emission angle distribution and so on, of atoms in laser field pulses with different laser parameters. For the linearly polarized laser pulses, the time-energy distribution intuitively shows from a quantum point of view the relationship between the ionization moment and the final energy and clearly reveals the origin of interference structures in the photoelectron spectrum. In particular, for linearly polarized few-cycle laser pulses, all calculated distributions show the dependence of electron behavior on the ionization time, emission direction, and carrier-envelope phase (CEP). For elliptically polarized few-cycle pulses, we calculate the angular distribution, ionization time distribution, and time-emission distribution, which are compared with the semiclassical calculations. Analysis shows that the offset angle (difference between positions of the peaks in the angular distributions obtained by two methods) in the angular distributions does not correspond to the offset time (difference between positions of the peaks in the ionization time distributions obtained by two methods) in the ionization time distributions, which implies that the attosecond angular streaking technique based on this correspondence between the offset angle and time is in principle inaccurate. Furthermore, the offset time cannot be interpreted as tunneling time.
The dipeptide dl-methionyl-dl-methionine (Met-Met) has extremely low water solubility and better absorption than other methionine sources (such as dl-methionine and l-methionine) available in the market. Therefore, six diets (D1, D2, D3, D4, D5 and D6) containing 0, 0·07, 0·15, 0·21, 0·28 and 0·38 % Met-Met were formulated to investigate the effects of Met-Met in juvenile Nile tilapia, Oreochromis niloticus (17 g initial body weight). The results indicated that percentage weight gain and specific growth rate of fish fed with D2 and D3 diets were higher than those fed with D1, D4–D6 diets. The levels of total essential amino acid in whole body of fish fed with D3 and D4 diets were significantly higher than those fed the D1 diet. Superoxide dismutase activity and malondialdehyde content have no significant difference in fish fed the diet with or without Met-Met supplementation. Majority of reads derived from the fish intestine belonged to members of Fusobacteria, followed by Bacteroidetes and Proteobacteria. Diversity of intestinal microbiota and total antioxidant capacity in fish fed with D3 diet was significantly higher than that of other groups. Based on the growth results, the authors conclude that the optimal level of Met is 0·61 % Met with the addition of 0·15 % Met-Met for grower-phase O. niloticus.
Using ethanol adsorption calorimetry, the surface energetics of two carbon substrates and two products in microwave-assisted carbon nanotube (CNT) growth was studied. In this study, the ethanol adsorption enthalpies of the two graphene-based samples at 25 °C were measured successfully. Specifically, the near-zero differential enthalpies of ethanol adsorption are −75.7 kJ/mol for graphene and −63.4 kJ/mol for CNT-grafted graphene. Subsequently, the differential enthalpy curve of each sample becomes less exothermic until reaching a plateau, −55.8 kJ/mol for graphene and −49.7 kJ/mol for CNT-grafted graphene, suggesting favorable adsorbate–adsorbent binding. Moreover, the authors interpreted and discussed the partial molar entropy and chemical potential of adsorption as the ethanol surface coverage (loading) increases. Due to the low surface areas of carbon black–based samples, adsorption calorimetry could not be performed. This model study demonstrates that using adsorption calorimetry as a fundamental tool and ethanol as the molecular probe, the overall surface energetics of high–surface area carbon materials can be estimated.
Facilitated by the establishment of terrestrial networks and satellite constellations of Automatic Identification System (AIS) receivers, large quantities of spatial and temporal information that trace ships' paths have been collected. The exponential increase in the amount of AIS data has caused expensive and time-consuming transmission, calculation and storage problems. Using appropriate trajectory simplification methods in a timely manner to compress redundant information while minimising the loss of importation information is important. To minimise the simplification error, this paper proposes an online multi-dimensional simplification algorithm for AIS trajectory streaming data. The simplification algorithm takes into account position, direction and speed preservation. Finally, a comparison experiment with other algorithms is made to examine the effectiveness of this algorithm. The results indicate that the proposed online multi-dimensional simplification algorithm can effectively preserve a ship's motion state, including its position, speed and course.
High inductive helical support provides a solution to controlling the alignment error of inner electrodes in magnetically insulated transmission lines (MITLs). Three-dimensional particle-in-cell simulations were performed to examine the current loss mechanism and the effects of structural parameters on electron flow in an MITL with a helical inductor. An empirical expression related to the ratio of electron current loss to anode current and the ratio of anode current to self-limited current was obtained. Electron current loss caused by helical inductor with different structures was displayed. The results indicate that the current loss in an MITL, near an inductive helical support, comprises both the inductor current and the electron current loss. The non-uniform structure and current of a helical inductor cause an abrupt change in the magnetic field near the helical support, which leads to anomalous behavior and current loss of electron flow. In addition, current loss in the inductive helical-supported MITL is negligible when the inductance of the support is sufficiently high. This work facilitates the estimation of electron current loss caused by the inductive helical support in MITLs.
Extant medusozoans (phylum Cnidaria) are dominated by forms showing tetraradial symmetry, but stem-group medusozoans of early Cambrian age collectively exhibit tetra-, bi-, penta-, and hexaradial symmetry. Moreover, the developmental and evolutionary relationships between four-fold and other types of radial symmetry in medusozoans remain poorly understood. Here we describe a new hexangulaconulariid, Septuconularia yanjiaheensis new genus new species, from Bed 5 of the Yanjiahe Formation (Cambrian Stage 2) in the Three Gorges area of Hupei Province, China. The laterally compressed, biradially symmetrical periderm of this species possesses 14 gently tapered faces, the most of any hexangulaconulariid described thus far. The faces are bordered by longitudinal ridges and crossed by short, irregularly spaced transverse ribs. Longitudinally, the periderm consists of three regions that probably correspond, respectively, to an embryonic stage, a transient juvenile stage, and a long adult stage. Septuconularia yanjiaheensis may have been derived from six-faced Hexaconularia (Fortunian Stage), which is morphologically intermediate between Septuconularia yanjiaheensis and Arthrochites. Furthermore, conulariids sensu stricto, carinachitids, and hexangulaconulariids may constitute a monophyletic group united by possession of an organic or organophosphatic periderm exhibiting longitudinal (corner) sulci, a facial midline, and offset of transverse ribs along the facial midline.
The effect of maternal folate intake on small-for-gestational-age (SGA) births remains inconclusive. The present study aimed to investigate the associations of maternal folate intake from diet and supplements with the risk of SGA births using data from a cross-sectional study in Shaanxi Province of Northwest China. A total of 7307 women who were within 12 months (median 3; 10th–90th percentile 0–7) after delivery were included. Two-level models were adopted to examine the associations of folate (dietary folate, supplemental folic acid and total folate) intake with the risk of SGA births and birth weight Z score, controlling for a minimum set of confounders that were identified in a directed acyclic graph. Results showed that a higher supplemental folic acid intake during the first trimester was negatively associated with the risk of SGA births (≤60 d v. non-use: OR 0·80; 95 % CI 0·66, 0·96; >60 d v. non-use: OR 0·78; 95 % CI 0·65, 0·94; Ptrend = 0·010; per 10-d increase: OR 0·97; 95 % CI 0·95, 0·99). A higher total folate intake during pregnancy was associated with a reduced risk of SGA births (highest tertile v. lowest tertile: OR 0·77; 95 % CI 0·64, 0·94; Ptrend = 0·010; per one-unit increase in the log-transformed value: OR 0·81; 95 % CI 0·69, 0·95). A similar pattern was observed for the birth weight Z score. Our study suggested that folic acid supplementation during the first trimester and a higher total folate intake during pregnancy were associated with a reduced risk of SGA births.
Echinococcus granulosus sensu stricto (s.s.), Echinococcus multilocularis and Echinococcus canadensis are the common causes of human echinococcosis in China. An accurate species identification tool for human echinococcosis is needed as the treatments and prognosis are different among species. The present work demonstrates a method for the simultaneous detection of these three Echinococcus species based on multiplex polymerase chain reaction (mPCR). Specific primers of this mPCR were designed based on the mitochondrial genes and determined by extensive tests. The method can successfully detect either separated or mixed target species, and generate expected amplicons of distinct size for each species. Sensitivity of the method was tested by serially diluted DNA, showing a detection threshold as less as 0.32 pg for both E. granulosus s.s. and E. canadensis, and 1.6 pg for E. multilocularis. Specificity assessed against 18 other parasites was found to be 100% except weakly cross-react with E. shiquicus. The assay was additionally applied to 69 echinococcosis patients and 38 healthy persons, confirming the high reliability of the method. Thus, the mPCR described here has high application potential for clinical identification purposes, and can further provide a useful tool for evaluation of serology and imaging method.
We aimed to investigate the association between plasma retinol and incident cancer among Chinese hypertensive adults. We conducted a nested case–control study, including 231 patients with incident cancer and 231 matched controls during a median 4·5-year follow-up of the China Stroke Primary Prevention Trial. There was a significant, inverse association between retinol levels and digestive system cancer (per 10 μg/dl increases: OR 0·79; 95 % CI 0·69, 0·91). When compared with participants in the first quartile of retinol (< 52·3 μg/dl), a significantly lower cancer risk was found in participants in quartile 2–4 ( ≥ 52·3 μg/dl: OR 0·31; 95 % CI 0·13, 0·71). However, there was a U-shaped association between retinol levels and non-digestive system cancers where the risk of cancers decreased (although not significantly) with each increment of plasma retinol (per 10 μg/dl increases: OR 0·89; 95 % CI 0·60, 1·31) in participants with retinol < 68·2 μg/dl, and then increased significantly with retinol (per 10 μg/dl increase: OR 1·65; 95 % CI 1·12, 2·44) in participants with retinol ≥ 68·2 μg/dl. In conclusion, there was a significant inverse dose–response association between plasma retinol and the risk of digestive system cancers. However, a U-shaped association was observed between plasma retinol and the risk of non-digestive cancers (with a turning point approximately 68·2 μg/dl).
Computerized cognitive remediation therapy (CCRT) is generally effective for the cognitive deficits of schizophrenia. However, there is much uncertainty about what factors mediate or moderate effectiveness and are therefore important to personalize treatment and boost its effects.
In total, 311 Chinese inpatients with Diagnostic and Statistical Manual of Mental Disorders-IV schizophrenia were randomized to receive CCRT or Active control for 12 weeks with four to five sessions per week. All participants were assessed at baseline, post-treatment and 3-month follow-up. The outcomes were cognition, clinical symptoms and functional outcomes.
There was a significant benefit in the MATRICS Consensus Cognitive Battery (MCCB) total score for CCRT (F1,258 = 5.62; p = 0.02; effect size was 0.27, 95% confidence interval 0.04–0.49). There were no specific moderators of CCRT improvements. However, across both groups, Wisconsin Card Sort Test improvement mediated a positive effect on functional capacity and Digit Span benefit mediated decreases in positive symptoms. In exploratory analyses younger and older participants showed cognitive improvements but on different tests (younger on Symbol Coding Test, while older on the Spatial Span Test). Only the older age group showed MSCEIT benefits at post-treatment. In addition, cognition at baseline negatively correlated with cognitive improvement and those whose MCCB baseline total score was around 31 seem to derive the most benefit.
CCRT can improve the cognitive function of patients with schizophrenia. Changes in cognitive outcomes also contributed to improvements in functional outcomes either directly or solely in the context of CCRT. Age and the basic cognitive level of the participants seem to affect the cognitive benefits from CCRT.