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.
The oxidation behavior of the selective laser melting (SLM)–fabricated Inconel 718 was investigated through isothermal oxidation testing at 650 °C for 500 h and compared with that of the as-cast and as-forged specimens at the same testing conditions. The effect of microstructure and surface roughness on the oxidation behavior of the SLM-fabricated, as-cast, and as-forged Inconel 718 specimens was examined. The result shows that Inconel 718 fabricated by SLM with the unique layer structure exhibited a better resistance to the 500 h oxidation at 650 °C compared with as-cast and as-forged 718 with coarse dendritic structure and uniform equiaxed grain microstructure, respectively. The influence of the surface roughness on the long-time oxidation resistance of SLM specimens is not pronounced compared with that of as-cast and as-forged specimens. The tiny dendrites instead of grain boundaries are a major influencing factor for the oxidation process of SLM specimens. The surface roughness has more evident influence on the oxidation resistance of as-forged specimens than that of the as-cast ones subjected to the 500 h oxidation at 650 °C.
To improve the corrosion resistance and to increase the hardness of copper substrate in marine environment, the Cu-Ni/Ni-P composite coatings were prepared on the copper substrate using the galvanostatic electrolytic deposition method. The deposition current densities were explored to find the optimized deposition conditions for forming the composite coatings. Corrosion resistance properties were analyzed using the polarization curves and electrochemical impedance spectroscopy (EIS). Considering the corrosion resistance and hardness, the −20 mA/cm2 was selected to deposit Cu-Ni coatings on copper substrate and the −30 mA/cm2 was selected to deposit Ni-P coating on the Cu-Ni layer. The Cu-Ni/Ni-P composite coatings not only exhibited superior corrosion resistance compared to single Cu-Ni coating in 3.5 wt.% NaCl solution, but also showed much better mechanical properties than single Cu-Ni coating.
Internationalization plays an important role in Huawei’s transformation from a fledgling Chinese start-up to a powerful multinational company. Huawei’s internationalization is characterized by repeated failures, difficult struggles and unceasing learning by doing. In this chapter, we divide the whole internationalization process of Huawei into three stages based on the different challenges at each stage. They are (1) overcoming the liability of foreignness, (2) managing complexity to achieve synergy from a global perspective, and (3) changing from a latecomer mindset to that of a global leader. For each stage, we summarize and discuss how Huawei adopts routinization and de-routinization strategies to efficiently overcome different challenges. The managerial implications derived from Huawei’s internationalization will be useful for other multinational firms.
Schizophrenia is a common major mental disorder and prenatal nutritional deficiency may increase its risk. We aimed to investigate long-term impact of prenatal exposure to malnutrition on risk of schizophrenia in adulthood using the Chinese famine of 1959–1961 as a natural experiment.
We obtained data from the Second National Sample Survey on Disability implemented in 31 provinces in 2006, and restricted our analysis to 387,093 individuals born from 1956 to 1965. Schizophrenia was ascertained by psychiatrists based on the International Statistical Classification of Diseases, Tenth Revision. Famine severity was defined as cohort size shrinkage index. The famine effect on adult schizophrenia was estimated by difference-in-difference models, established by examining the variations of famine exposure across birth cohorts.
Compared with the reference cohort of 1965, famine cohorts (1959–1962) had significantly higher odds (OR: 1.84; 95% CI: 1.13, 3.00; P = 0.014) of schizophrenia in the rural population. After adjusting for multiple covariates, this association remained significant (OR: 1.82; 95% CI: 1.11, 2.98; P = 0.018). We did not observe statistically significant differences in odds of schizophrenia among famine cohorts compared with the reference cohort in the urban population.
Prenatal malnutrition exposure has a detrimental impact on risk of schizophrenia in adulthood in the rural population. Further studies were needed to investigate corresponding mechanisms on this topic.
A CoNiCrAlTaHfY/Co composite coating was prepared on the etched C/C composites by using duplex vapor phase surface alloying treatments, i.e., Co alloying and Co–Ni–Cr–Al–Ta–Hf–Y alloying. Microstructures and oxidation behavior of the coated C/C composites were analyzed by scanning electron microscopy, energy-dispersive spectroscopy, and X-ray diffraction. The result showed that the CoNiCrAlTaHfY/Co composite coating, 25 μm in thickness, was compact and composed of CrCoTa, AlCo2Ta, AlxCry, AlxNiy, and Co. The coating adhesion can be enhanced by microwave plasma chemical vapor deposition etching of matrix surface and adding a Co intermediate layer between the CoNiCrAlTaHfY top layer and C/C composites substrate. The honeycomb structure after etching was helpful to alloying element absorb and diffuse into substrate surface, and the composite coating continuation was improved by the Co buffer layer. After exposing in air for 180 min at 1000 °C, the bulk C/C composites volatilized while the loss rate of coated C/C composites was 0.82%, showing an improved oxidation resistance. Mixed oxides mainly containing Al2O3 and Cr2O3 were formed in the composite coating surface and protected the C/C composites from oxidation in air.
Iodine intake and excretion vary widely; however, these variations remain a large source of geometric uncertainty. The present study aims to analyse variations in iodine intake and excretion and provide implications for sampling in studies of individuals or populations. Twenty-four healthy women volunteers were recruited for a 12-d sampling period during the 4-week experiment. The duplicate-portion technique was used to measure iodine intake, while 24-h urine was collected to estimate iodine excretion. The mean intra-individual variations in iodine intake, 24-h UIE (24-h urinary iodine excretion) and 24-h UIC (24-h urinary iodine concentration) were 63, 48 and 55 %, respectively, while the inter-individual variations for these parameters were 14, 24 and 32 %, respectively. For 95 % confidence, approximately 500 diet samples or 24-h urine samples should be taken from an individual to estimate their iodine intake or iodine status at a precision range of ±5%. Obtaining a precision range of ±5% in a population would require twenty-five diet samples or 150 24-h urine samples. The intra-individual variations in iodine intake and excretion were higher than the inter-individual variations, which indicates the need for more samples in a study on individual participants.
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.
The co-occurrence of hepatic cystic echinococcosis (CE) and alveolar echinococcosis (AE) is extremely rare. Here, we present the clinical manifestations and treatment outcomes of three cases with co-occurring CE and AE in the liver. Computed tomography (CT), magnetic resonance imaging and 18FFluorodeoxyglucose Positron Emission Tomography-CT were used for preoperative diagnosis. Specimens were taken intraoperatively and sent for pathological studies to confirm the coexistence of CE and AE by laminated membrane, daughter cysts or germinal layer and infiltration structure. Albendazole was prescribed after operation for 12 months. All patients were completely recovered and showed no recurrence at last follow-up. Therefore, surgical intervention and postoperative application of albendazole are recommended for patients with concurrence of hepatic AE and CE.
Existing data on folate status and hepatocellular carcinoma (HCC) prognosis are scarce. We prospectively examined whether serum folate concentrations at diagnosis were associated with liver cancer-specific survival (LCSS) and overall survival (OS) among 982 patients with newly diagnosed, previously untreated HCC, who were enrolled in the Guangdong Liver Cancer Cohort (GLCC) study between September 2013 and February 2017. Serum folate concentrations were measured using chemiluminescent microparticle immunoassay. Cox proportional hazards models were performed to estimate hazard ratios (HR) and 95 % CI by sex-specific quartile of serum folate. Compared with patients in the third quartile of serum folate, patients in the lowest quartile had significantly inferior LCSS (HR = 1·48; 95 % CI 1·05, 2·09) and OS (HR = 1·43; 95 % CI 1·03, 1·99) after adjustment for non-clinical and clinical prognostic factors. The associations were not significantly modified by sex, age at diagnosis, alcohol drinking status and Barcelona Clinic Liver Cancer (BCLC) stage. However, there were statistically significant interactions on both multiplicative and additive scale between serum folate and C-reactive protein (CRP) levels or smoking status and the associations of lower serum folate with worse LCSS and OS were only evident among patients with CRP > 3·0 mg/l or current smokers. An inverse association with LCSS were also observed among patients with liver damage score ≥3. These results suggest that lower serum folate concentrations at diagnosis are independently associated with worse HCC survival, most prominently among patients with systemic inflammation and current smokers. A future trial of folate supplementation seems to be promising in HCC patients with lower folate status.
We previously reported four heterozygous missense mutations of MYH7, KCNQ1, MYLK2, and TMEM70 in a single three-generation Chinese family with dual Long QT and hypertrophic cardiomyopathy phenotypes for the first time. However, the clinical course among the family members was various, and the potential myocardial dysfunction has not been investigated.
The objective of this study was to investigate the echocardiographic and electrocardiographic characteristics in a genetic positive Chinese family with hypertrophic cardiomyopathy and further to explore the association between myocardial dysfunction and electric activity, and the identified mutations.
A comprehensive echocardiogram – standard two-dimensional Doppler echocardiography and three-dimensional speckle tracking echocardiography – and electrocardiogram were obtained for members in this family.
As previously reported, four missense mutations – MYH7-H1717Q, KCNQ1-R190W, MYLK2-K324E, and TMEM70-I147T – were identified in this family. The MYH7-H1717Q mutation carriers had significantly increased left ventricular mass indices, elevated E/e’ ratio, deteriorated global longitudinal stain, but enhanced global circumferential and radial strain compared with those in non-mutation patients (all p<0.05). The KCNQ1-R190W carriers showed significantly prolonged QTc intervals, and the MYLK2-K324E mutation carriers showed inverted T-waves (both p<0.05). However, the TMEM70-I147T mutation carriers had similar echocardiography and electrocardiographic data as non-mutation patients.
Three of the identified four mutations had potential pathogenic effects in this family: MYH7-H1717Q was associated with increased left ventricular thickness, elevated left ventricular filling pressure, and altered myocardial deformation; KCNQ1-R190W and MYLK2-K324E mutations were correlated with electrocardiographic abnormalities reflected in long QT phenotype and inverted T-waves, respectively.
MicroRNA (miR)-29b plays a crucial role during somatic cell reprogramming. The aim of the current study was to explore the effects of miR-29b on the developmental competence of bovine somatic cell nuclear transfer (SCNT) embryos, as well as the underlying mechanisms of action. The expression level of miR-29b was lower in bovine SCNT embryos at the pronuclear, 8-cell, and blastocyst stages compared with in vitro fertilized embryos. In addition, miR-29b regulates the expression of DNA methyltransferases (Dnmt3a/3b and Dnmt1) in bovine SCNT embryos. We further investigated SCNT embryo developmental competence and found that miR-29b overexpression during bovine SCNT embryonic development does not improve developmental potency and downregulation inhibits developmental potency. Nevertheless, the quality of bovine SCNT embryos at the blastocyst stage improved significantly. The expression of pluripotency factors and cellular proliferation were significantly higher in blastocysts from the miR-29b overexpression group than the control and downregulation groups. In addition, outgrowth potential in blastocysts after miR-29b overexpression was also significantly greater in the miR-29b overexpression group than in the control and downregulation groups. Taken together, these results demonstrated that miR-29b plays an important role in bovine SCNT embryo development.
Motion compensation is a significant part of an airborne remote sensing system. A Position and Orientation System (POS) can directly measure the motion information of an airborne remote sensing payload that can improve the quality of airborne remote sensing images. Gravity disturbance, information on which is often ignored due to being difficult to acquire in real-time, has become the main error source of POS in the development of inertial components. In this paper, a new real-time gravity compensation method is proposed, which includes the gravity disturbance as the error states of a POS Kalman filter, and an accurate gravity disturbance model is constructed using a time-varying Gaussian-Markov model based on a high-precision gravity map, whose resolution is enhanced by a new interpolation method based on Gaussian Process Regression (GPR). A flight experiment was conducted to evaluate the efficiency of the proposed method and the results showed that the proposed method performs well when compared with other real-time gravity compensation methods.
The degradation, alteration and depletion of riparian habitats caused by river regulation are among critical conservation concerns. Aquatic and riparian habitats support not only river-dwelling biota such as macroinvertebrates and fish, but also waterbirds, the top predators in the aquatic food web. Despite the intimate relationships between fish and waterbirds, the two groups are often investigated separately. Using an integrative approach, we examined the effects of dams on fish and scaly-sided merganser (Mergus squamatus), an endangered, iconic riverine species, where the lack of knowledge about habitat preferences greatly hampers long-term conservation efforts. Our analysis quantified three causal links: (1) water depth had direct, comparable, negative effects on both fish and waterbirds, and the path coefficients for fish and birds are –0.31 and –0.46, respectively; (2) river landscape heterogeneity directly and positively affected fish and waterbirds, and the path coefficients for fish and birds are 0.63 and 0.19, respectively; and (3) depth and river landscape also exerted indirect effects on waterbirds through their impacts on fish abundance, and the path coefficients for fish and birds are –0.15 and 0.28, respectively. Our findings could contribute to the rational spatial planning and sustainable operation of dams in that maintaining instream habitat availability and heterogeneity would benefit the whole riverine ecosystem.
We examined the in vitro developmental competence of parthenogenetic activation (PA) oocytes activated by an electric pulse (EP) and treated with various concentrations of AZD5438 for 4 h. Treatment with 10 µM AZD5438 for 4 h significantly improved the blastocyst formation rate of PA oocytes in comparison with 0, 20, or 50 µM AZD5438 treatment (46.4% vs. 34.5%, 32.3%, and 24.0%, respectively; P < 0.05). The blastocyst formation rate was higher in the group treated with AZD5438 for 4 h than in the groups treated with AZD5438 for 2 or 6 h (42.8% vs. 38.6% and 37.2%, respectively; P > 0.05). Furthermore, 66.67% of blastocysts derived from these AZD5438-treated PA oocytes had a diploid karyotype. The blastocyst formation rate of PA and somatic cell nuclear transfer (SCNT) embryos was similar between oocytes activated by an EP and treated with 2 mM 6-dimethylaminopurine for 4 h and those activated by an EP and treated with 10 µM AZD5438 for 4 h (11.11% vs. 13.40%, P > 0.05). In addition, the level of maturation-promoting factor (MPF) was significantly decreased in oocytes activated by an EP and treated with 10 µM AZD5438 for 4 h. Finally, the mRNA expression levels of apoptosis-related genes (Bax and Bcl-2) and pluripotency-related genes (Oct4, Nanog, and Sox2) were checked by RT-PCR; however, there were no differences between the AZD5438-treated and non-treated control groups. Our results demonstrate that porcine oocyte activation via an EP in combination with AZD5438 treatment can lead to a high blastocyst formation rate in PA and SCNT experiments.
Brief cognitive–behavioural therapy (CBT) is an emerging treatment for
schizophrenia in community settings; however, further trials are needed,
especially in non-Western countries.
To test the effects of brief CBT for Chinese patients with schizophrenia
in the community (trial registration: ChiCTR-TRC-13003709).
A total of 220 patients with schizophrenia from four districts of Beijing
were randomly assigned to either brief CBT plus treatment as usual (TAU)
or TAU alone. Patients were assessed at baseline, post-treatment and at
6- and 12-month follow-ups by raters masked to group allocation.
At the post-treatment assessment and the 12-month follow-up, patients who
received brief CBT showed greater improvement in overall symptoms,
general psychopathology, insight and social functioning. In total, 37.3%
of those in the brief CBT plus TAU group experienced a clinically
significant response, compared with only 19.1% of those in the TAU alone
group (P = 0.003).
Brief CBT has a positive effect on Chinese patients with schizophrenia in
There has been a lot of study on the SOR-like methods for solving the augmented system of linear equations since the outstanding work of Golub, Wu and Yuan (BIT 41(2001)71-85) was presented fifteen years ago. Based on the SOR-like methods, we establish a class of accelerated SOR-like methods for large sparse augmented linear systems by making use of optimization technique, which will find the optimal relaxation parameter ω by optimization models. We demonstrate the convergence theory of the new methods under suitable restrictions. The numerical examples show these methods are effective.