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We report on a novel processing route to prepare La0.8Ce0.2(Fe0.95Co0.05)11.8Si1.2/Cu bulk composites by low-temperature hot pressing. With increasing copper content, the compressive strength of the composites first decrease and then increase owing to the buffering effect of copper, but the magnetocaloric effect reduces to some extent. Copper addition improves the thermal conductivity of the composites, which compensates for the decrease in thermal conductivity due to porosity. A relatively large entropy change of 5.75–7.19 J/(kg K) at 2 T near the Curie temperature (249 K), good thermal conductivity of 7.51–15.55 W/(m·K), and improved compressive strength of 151.1–248.0 MPa make these composites attractive magnetic refrigeration materials.
Suicide-related behaviours are common in schizophrenia and are significantly associated with premature death. The objective of this meta-analysis study was to estimate the pooled prevalence of suicide-related behaviours in schizophrenia patients in China.
The relevant literature was searched systematically via the relevant electronic databases (PubMed, Embase, PsycINFO, Chinese National Knowledge Infrastructure, Wanfang Databases and Chinese Biological Medical Literature Database) from their inception until 14 September 2016. Only original studies that reported the prevalence of suicide-related behaviours including suicidal ideation (SI), suicide plan, suicide attempt (SA) and completed suicide were selected.
Nineteen articles met the inclusion criteria and were analysed. The pooled lifetime prevalence of SI and SA were 25.8% (95% CI 14.7–41.1%) and 14.6% (95% CI 9.1–22.8%), respectively. The 1-month prevalence of SI was 22.0% (95% CI 18.2–26.4%). Subgroup analyses of lifetime SI and SA showed that gender, sample size, survey year, study location and source of patients have no significant mediating effects on the results.
Suicide-related behaviours are common in Chinese schizophrenia patients. Due to the high mortality risk, regular screening and effective suicide prevention programmes are warranted.
In recent years, the effect of Toxoplasma gondii infection on the cerebrum and neuropsychiatric patients has been increasingly highlighted. However, there is limited information about the epidemiology of T. gondii infection in psychiatric patients in Shandong province, eastern China. Therefore, through a case-control study, 445 patients hospitalized for diacrisis or treatment in Weihai, eastern China, and 445 control subjects from the general population of the same region matched by gender, age, and residence were examined with enzyme-linked immunoassays for the presence of IgG and IgM antibodies to T. gondii and associated sociodemographic and behavioural characteristics in a population of psychiatric patients. Seroprevalence of IgG antibodies to T. gondii in psychiatric patients (77/445, 17·30%) was significantly higher than in control subjects (55/445, 12·36%) (P = 0·038). Fourteen (3·15%) psychiatric patients and 10 (2·25%) control subjects had IgM antibodies to T. gondii (P = 0·408). Multivariate analysis using logic regression showed that T. gondii infection was associated with cats at home and consumption of raw/undercooked meat in psychiatric patients. Considering that most psychiatric patients usually have lower cognitive functioning and additional transmission routes related to their inappropriate behaviours that could enhance the risk of infection, psychiatric patients should be considered as a specific group of T. gondii infection.
Despite substantial research, uncertainty remains about the clinical and etiological heterogeneity of major depression (MD). Can meaningful and valid subtypes be identified and would they be stable cross-culturally?
Symptoms at their lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years, with recurrent DSM-IV MD. Latent class analysis (LCA) was performed in Mplus.
Using the nine DSM-IV MD symptomatic A criteria, the 14 disaggregated DSM-IV criteria and all independently assessed depressive symptoms (n = 27), the best LCA model identified respectively three, four and six classes. A severe and non-suicidal class was seen in all solutions, as was a mild/moderate subtype. An atypical class emerged once bidirectional neurovegetative symptoms were included. The non-suicidal class demonstrated low levels of worthlessness/guilt and hopelessness. Patterns of co-morbidity, family history, personality, environmental precipitants, recurrence and body mass index (BMI) differed meaningfully across subtypes, with the atypical class standing out as particularly distinct.
MD is a clinically complex syndrome with several detectable subtypes with distinct clinical and demographic correlates. Three subtypes were most consistently identified in our analyses: severe, atypical and non-suicidal. Severe and atypical MD have been identified in multiple prior studies in samples of European ethnicity. Our non-suicidal subtype, with low levels of guilt and hopelessness, may represent a pathoplastic variant reflecting Chinese cultural influences.
The symptoms of major depression (MD) are clinically diverse. Do they form coherent factors that might clarify the underlying nature of this important psychiatric syndrome?
Symptoms at lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years with recurrent DSM-IV MD. Exploratory factor analysis (EFA) and confirmatoryfactor analysis (CFA) were performed in Mplus in random split-half samples.
The preliminary EFA results were consistently supported by the findings from CFA. Analyses of the nine DSM-IV MD symptomatic A criteria revealed two factors loading on: (i) general depressive symptoms; and (ii) guilt/suicidal ideation. Examining 14 disaggregated DSM-IV criteria revealed three factors reflecting: (i) weight/appetite disturbance; (ii) general depressive symptoms; and (iii) sleep disturbance. Using all symptoms (n = 27), we identified five factors that reflected: (i) weight/appetite symptoms; (ii) general retarded depressive symptoms; (iii) atypical vegetative symptoms; (iv) suicidality/hopelessness; and (v) symptoms of agitation and anxiety.
MD is a clinically complex syndrome with several underlying correlated symptom dimensions. In addition to a general depressive symptom factor, a complete picture must include factors reflecting typical/atypical vegetative symptoms, cognitive symptoms (hopelessness/suicidal ideation), and an agitated symptom factor characterized by anxiety, guilt, helplessness and irritability. Prior cross-cultural studies, factor analyses of MD in Western populations and empirical findings in this sample showing risk factor profiles similar to those seen in Western populations suggest that our results are likely to be broadly representative of the human depressive syndrome.
Previous studies support Beck's cognitive model of vulnerability to depression. However, the relationship between his cognitive triad and other clinical features and risk factors among those with major depression (MD) has rarely been systematically studied.
The three key cognitive symptoms of worthlessness, hopelessness and helplessness were assessed during their lifetime worst episode in 1970 Han Chinese women with recurrent MD. Diagnostic and other risk factor information was assessed at personal interview. Odds ratios (ORs) were calculated by logistic regression.
Compared to patients who did not endorse the cognitive trio, those who did had a greater number of DSM-IV A criteria, more individual depressive symptoms, an earlier age at onset, a greater number of episodes, and were more likely to meet diagnostic criteria for melancholia, postnatal depression, dysthymia and anxiety disorders. Hopelessness was highly related to all the suicidal symptomatology, with ORs ranging from 5.92 to 6.51. Neuroticism, stressful life events (SLEs) and a protective parental rearing style were associated with these cognitive symptoms.
During the worst episode of MD in Han Chinese women, the endorsement of the cognitive trio was associated with a worse course of depression and an increased risk of suicide. Individuals with high levels of neuroticism, many SLEs and high parental protectiveness were at increased risk for these cognitive depressive symptoms. As in Western populations, symptoms of the cognitive trio appear to play a central role in the psychopathology of MD in Chinese women.
Transparent films of platinum nanoparticles on graphene nanohybrids were synthesized in a two-step process. Reduction of homogeneously dispersed Pt precursor and graphene in water and solution coating/annealing afforded thin films with high catalytic performance as counter electrodes in dye-sensitized solar cells (DSSC). The requisite dispersant consisting of poly(oxyethylene)-(POE) segments and cyclic imide functionalities allowed the in-situ reduction of dihydrogen hexachloroplatinate by ethanol and the formation of nanohybrids of graphene-supported Pt nanoparticles at 4.0 nm diameter. Characterizations of polymeric dispersants by Fourier-transform infrared spectroscopy, thermogravimetric analysis, and nanohybrids by transmission electron microscope were performed. After screening various compositions of Pt/graphene, the nanohybrid film at the specific ratio of 5/1 by weight was fabricated into a counter electrode (CE) for DSSC by the solution casting method. The evaluation of cell performance demonstrated the most improved power conversion efficiency of 8.00%. This is significant achievement in comparison with 7.14% for the DSSC with the conventional platinum sputtered CE. Furthermore, the solution casting method allows the preparation of transparent CE films that are suitable for using as rear-illuminated DSSC. The approach was proven to be feasible by measuring the cell efficiency under rear light illumination. The power efficiency up to 7.01%, comparable to 8.00% by a normally front illumination, has been accomplished. In contrast, the rear illumination at merely 2.36% efficiency was obtained for the DSSC with sputtered platinum CE. Analyses of cyclic voltammetry, electrochemical impedance spectra were well correlated to the high efficiency of the performance caused by this nanohybrid film.
We like to report a novel conductive film containing graphene-silver nanohybrids from the process of solution coating and annealing at low-temperature for melting silver nanoparticles (AgNPs) into interconnected Ag matrice on surface. The fabrication required the assistance of a home-made polymeric dispersant, poly(oxyethylene)-segmented imide (POE-imide), for homogenize the AgNPs and graphene in hybridized form. The intermediate dispersion of AgNPs at 10–25 nm diameter on the surface of 2D-graphene were characterized and subsequently subjected to solution coating into thin films. Under the annealing temperature as low as 160 °C, the films exhibited a high electric conductivity or low sheet resistance at 2.4×10–1 Ω/sq (equivalent to 7.9×104 S/cm). It is noteworthy that the significant point of low-temperature annealing at 160–170 °C that is attributed to the fast deterioration and degradation of the POE-imide organics kinetically before the AgNP coalescence and melting. Furthermore, the comparisons of using silicate clays and carbon nanotubes in replacing the 2D graphene for hybridizing Ag had revealed the different morphologies in Ag networks. The findings of using the polymeric dispersion for synthesizing nanohybrids may open up a new avenue for making films with integrated properties of flexibility, transparency and high conductivity for a host of electronic applications.
The magnetic reconnection (MR) configuration was constructed by using two approaching laser-produced plasma bubbles. The characteristics of the MR current sheet were investigated. The driving energy of the laser pulse affects the type of the current sheet. The experiments present “Y-type” and “X-type” current sheets for larger and smaller driving energy, respectively. The energetic electrons were found to be well-collimated. The formation and ejection of plasmoid from the “Y-type” current sheet was expected to enhance the number of accelerated electrons.
Metastasis to regional lymph nodes via lymphatic microvessels plays a key role in cancer progression, and is an important prognostic factor in many cancers. Recent evidence suggests that tumour lymphangiogenesis promotes lymphatic metastasis.
To investigate whether tumour lymphatic microvessel density correlates with clinicopathological factors and serves as a prognostic indicator of supraglottic laryngeal carcinoma progression.
The lymphatics of 84 supraglottic laryngeal carcinoma cases were investigated by immunohistochemical staining for podoplanin (also termed D2-40). The relationships between (intra- and peritumoural) lymphatic microvessel density, clinicopathological parameters and clinical prognosis were analysed.
There was a significant relationship between high intratumoural lymphatic microvessel density and aggressive tumour node stage (p < 0.0001), distant metastasis (p = 0.037) and poor prognosis (p = 0.011), and between high peritumoural lymphatic microvessel density and node stage (p = 0.004) and poor prognosis (p = 0.029). Patients with high lymphatic microvessel density also had significantly worse disease-free survival (p = 0.003) and overall survival (p = 0.005). Intratumoural lymphatic microvessel density was found to be an independent prognostic factor for overall survival (p = 0.008) and disease-free survival (p = 0.005) (multivariate analysis).
Lymphatic microvessel density (detected by podoplanin immunohistochemistry), especially intratumoural density, may be an independent predictor of lymphatic tumour spread and survival in supraglottic laryngeal carcinoma patients, and may be useful to guide decisions regarding additional surgery.
The subtotal laryngectomy procedure enables the patient to avoid some of the serious consequences of total laryngectomy without having to relinquish oncological effectiveness. However, the important complication of aspiration may still seriously affect some patients. Many methods of reconstruction have been described in an attempt to avoid or minimise this complication.
Thirty-nine patients (15 with supraglottic laryngeal cancer and 24 with hypopharyngeal cancer) who had undergone subtotal laryngectomy between 2000 and 2006 were included in this study. In all patients, a sternohyoid muscle flap has been used for primary, one-stage reconstruction of laryngopharyngeal defects, following resection of advanced stage lesions. Patients' times to oral intake and decannulation, their speech function and their post-operative complications were reviewed.
The patients' three-year overall survival rate was 46.1 per cent. Their mean time to oral intake was 14 days. Twenty-six patients were decannulated (66.7 per cent). Almost all patients regained their speech function post-operatively, although their voice quality was not as good as before surgery.
Sternohyoid muscle fascia reconstruction leads to optimal repair of subtotal laryngectomy defects and restored laryngeal function.
This paper reports the first results of an ongoing
research work on rapid surface alloying of an AISI 316L stainless steel by
low energy, high current pulsed electron beam (LEHCPEB) with the aim of
enhancing the corrosion resistance of this material against aggressive
halide ions. A Ti powder layer was deposited on the substrate and
in-corporate at the top surface by using LEHCPEB. Due to the rapid surface
melting, liquid state mixing occurred and a Ti-rich layer formed. The
alloyed layer contained a mixture of the
and γ phases
because the addition of Ti favors the formation of α. The corrosion
resistance of the AISI 316L stainless steel in the simulated body fluid was
effectively improved after surface alloying by Ti.
A NiTi shape memory alloy was subjected to low energy high current pulsed
electron beam (LEHCPEB) irradiation. The samples were treated with the same
electron beam parameters and increasing number of pulses. The treatment
induces superfast melting, evaporation and rapid solidification at the top
surface. As a result of selective evaporation of Ni, the Ti content was
increased in the melted layer of the 5 pulse treated sample. However, for
the 10 pulsed sample, a part of the vapor condensed on the surface. It is
shown also that in the sub-surface, below the melted layer, the martensitic
transformation was triggered due to the effects of the thermal stresses and
shock waves propagating in the material.
We report on the visible and infrared emission characteristics of Er-doped III-N lightemitting diodes (LEDs). Quantum well-like device structures were grown through a combination of metal-organic chemical vapor deposition (MOCVD) and molecular beam epitaxy (MBE) on cplane sapphire substrates. The dual stage growth process was used to take advantage of the high quality of AlGaN layers produced by MOCVD and in situ doping of Er during MBE growth. The multilayer structures were processed into devices and LEDs with different sizes and geometric shapes were produced. Electroluminescence (EL) was observed under either forward or reverse bias conditions. Visible and infrared spectra displayed narrow emission lines representative of the Er3+ system. The temperature dependence of the spectra, which were measured from 100K to 300K, showed a stability in the visible emission intensity but a sharp decrease in the infrared intensity at room temperature. Based on light output vs current measurements, estimates of the excitation cross-section were obtained for visible EL emission.
Due to external loads, damage extension forces will drive mechanical and electrical damages to evolve in piezoelectric materials from the viewpoint of continuum damage mechanics, so it is important for understanding piezoelectric fracture mechanism and estimating the utilizing life and safety of a piezoelectric device to study the damage extension forces. Based on the static piezoelectric damage constitutive model established in our previously published papers, general expressions of the damage extension forces are given. The finite element method and the iterative procedure are utilized to calculate the extension forces at crack-tips in the samples for the experiments of Park and Sun's, and then the linear and nonlinear fracture criteria are presented. It is revealed from the list of the normalized mean square deviations that the nonlinear criterion is better.
The presence of a superstructure is identified to play a key role for the modifications in both superconductivity and structure transitions in the Mg1-xAlxB2 system. This superstructure occurs along the c-axis direction, and can be well interpreted by Al-layer ordering. The optimal composition of the superstructure phase is MgAlB4, a superconductor with Tc ∼12K. Raman spectrum of MgAlB4 gives rise to a sharp peak at around 941cm−1. Brief diagrams illustrating the superconductivity and structural features of Mg1-xAlxB2 (0≤x≤1) materials are presented.
Samples of the spontaneously ordered Ga0.5In0.5P alloys were grown by the MOCVD method on -oriented GaAs substrates. The thickness of the epitaxal layer is about 2 μm. Raman scattering and photoluminescence spectra have been measured at room temperature. The result from photoluminescence measurement indicates that the direct-band gaps of the spontaneously ordered samples are lower than that of the disordered sample. Three scattering peaks have been observed in the Raman spectra, corresponding to the GaP-like LO, InP-like LO and InP-like TO modes in the alloys, respectively. The frequencies of the GaP- and InP-like LO modes increase with the decrease of the band-gap of the ordered alloys. It is related to the formation of the (GaP)1/(InP)1 monolayer superlattice along  direction in the ordered alloys. The polarization properties of the ordered alloys are similar to those of the bulk III-V semiconductors with the zinc-blende structure.
Formation and electronic structure of the Mn/GaAs(100) interface grown at room temperature are studied by photoemission. The growth at early stage is identified to be in two-dimensional mode. The chemical reaction and the interface diffusion happened between Mn and GaAs are explored in some details. A ferromagnetic phase of Mn overlayer at early stage is deduced from the change of electron density of states near the Fermi edge.
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