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Cognitive impairment in late-life depression is common and associated with a higher risk of all-cause dementia. Late-life depression patients with comorbid cardiovascular diseases (CVDs) or related risk factors may experience higher risks of cognitive deterioration in the short term. We aim to investigate the effect of CVDs and their related risk factors on the cognitive function of patients with late-life depression.
A total of 148 participants were recruited (67 individuals with late-life depression and 81 normal controls). The presence of hypertension, coronary heart disease, diabetes mellitus, or hyperlipidemia was defined as the presence of comorbid CVDs or related risk factors. Global cognitive functions were assessed at baseline and after a one-year follow-up by the Mini-Mental State Examination (MMSE). Global cognitive deterioration was defined by the reliable change index (RCI) of the MMSE.
Late-life depression patients with CVDs or related risk factors were associated with 6.8 times higher risk of global cognitive deterioration than those without any of these comorbidities at a one-year follow-up. This result remained robust after adjusting for age, gender, and changes in the Hamilton Depression Rating Scale (HAMD) scores.
This study suggests that late-life depression patients with comorbid CVDs or their related risk factors showed a higher risk of cognitive deterioration in the short-term (one-year follow up). Given that CVDs and their related risk factors are currently modifiable, active treatment of these comorbidities may delay rapid cognitive deterioration in patients with late-life depression.
Soil moisture is a key factor in the ecohydrological cycle in water-limited ecosystems, and it integrates the effects of climate, soil, and vegetation. The water balance and the hydrological cycle are significantly important for vegetation restoration in water-limited regions, and these dynamics are still poorly understood. In this study, the soil moisture and water balance were modelled with the stochastic soil water balance model in the Loess Plateau, China. This model was verified by monitoring soil moisture data of black locust plantations in the Yangjuangou catchment in the Loess Plateau. The influences of a rainfall regime change on soil moisture and water balance were also explored. Three meteorological stations were selected (Yulin, Yan'an, and Luochuan) along the precipitation gradient to detect the effects of rainfall spatial variability on the soil moisture and water balance. The results showed that soil moisture tended to be more frequent at low levels with decreasing precipitation, and the ratio of evapotranspiration under stress in response to rainfall also changed from 74.0% in Yulin to 52.3% in Luochuan. In addition, the effects of a temporal change in rainfall regime on soil moisture and water balance were explored at Yan'an. The soil moisture probability density function moved to high soil moisture in the wet period compared to the dry period of Yan'an, and the evapotranspiration under stress increased from 59.5% to 72% from the wet period to the dry period. The results of this study prove the applicability of the stochastic model in the Loess Plateau and reveal its potential for guiding the vegetation restoration in the next stage.
Over the recent years, potential associations between Toxoplasma gondii (T. gondii) infection and cancer risk have attracted a lot of attention. Nevertheless, the association between T. gondii infection and oral cancer remains relatively unexplored. We performed a case–control study of 861 oral cancer patients and 861 control subjects from eastern China with the aim to detect antibodies to T. gondii by enzyme-linked immunosorbent assay (ELISA) in these patients. The results showed that oral cancer patients (21.72%, 187/861) had a significantly higher seroprevalence than control subjects (8.25%, 71/861) (P < 0.001). Among them, 144 (16.72%) oral cancer patients and 71 (8.25%) control subjects were positive for IgG antibodies to T. gondii, while 54 (6.27%) oral cancer patients and 9 (1.05%) controls were positive for IgM antibodies to T. gondii. In addition, multiple logistic analysis showed that T. gondii infection in oral cancer patients was associated with blood transfusion history, keeping cats at home, and oyster consumption. To our knowledge, this is the first study that provided a serological evidence of an association between T. gondii infection and oral cancer patients. However, further studies are necessary to elucidate the role of T. gondii in oral cancer patients.
In this study, wideband bandpass power divider with good out-of-band performance is proposed. Two bandpass filters (BPFs) are utilized to substitute the quarter-wavelength transmission line in conventional Wilkinson power divider. A resistor is specially arranged between two BPFs for a good isolation. Four transmission zeros (TZs) are found to be distributed in the lower and upper stopband of the power divider. Moreover, the locations of two TZs can be shifted by tuning the impedance ratio of the center-loaded open stub, which is propitious to improve the frequency selectivity. Even- and odd-mode methods are applied to analyze the proposed power divider and closed-form design formulas are obtained. Finally, two prototype power dividers with measured rejection level in the upper stopband larger than 29.1 and 32 dB till to 2.7f0 and 2.69f0, respectively, are designed and fabricated to testify the proposed design concept. Good agreement between the simulated and measured results is observed, validating the validity of the proposed design principle.
As one of the major components of the Himalayan–Tibetan Orogeny, the Lhasa terrane plays a key role in understanding the origin and evolution of this giant orogenic belt and the opening and closure of the Tethys oceans. The eclogite-bearing Sumdo Complex in the central Lhasa terrane was recognized as the main suture of the Palaeo-Tethys Ocean between the north and south Lhasa sub-terranes. Despite the eclogite having been studied for a long time, no attempts have been applied to studying the country rocks, causing confusion in understanding the relationship between the eclogite and the adjacent schist. Petrological investigations and phase equilibrium calculations on the garnet-bearing mica schist of the Sumdo Complex have been performed to constrain its metamorphic evolution. The P–T conditions for three metamorphic stages are constrained as P1 (480–500°C, 2.6–2.7 GPa), P2 (580–600°C, 1.3–1.4 GPa) and R (530°C, 0.9 GPa), which represent the prograde, temperature peak and retrograde stages. Two possible P–T paths were constructed, which experienced isothermal decompression (PT1) or heating with a decompression process (PT2), corresponding to the growth and extinction of garnet porphyroblasts in the matrix. The LA-MC-ICP-MS U–Pb dating method yielded a metamorphic age of 229.7±3.5 Ma, which was interpreted as the age of amphibolite-facies metamorphism at c. 600°C, 1.2–1.4 GPa during the closure of the Palaeo-Tethys Ocean, resulting in the aggregation of the north and south Lhasa sub-terranes. The close relationship between the eclogite and garnet-bearing mica schist, and their similar P–T–t paths indicate an in situ tectonic evolution rather than tectonic juxtaposition during exhumation.
This research paper addresses the hypothesis that RagD is a key signalling factor that regulates amino acid (AA) mediated-casein synthesis and cell proliferation in cow mammary epithelial cells (CMECs). The expression of RagD was analysed at different times during pregnancy and lactation in bovine mammary tissue from dairy cows. We showed that expression of RagD at lactation period was higher (P < 0·05) than that at pregnancy period. When CMECs were treated with methionine (Met) or lysine (Lys), expression of RagD, β-casein (CSN2), mTOR and p-mTOR, and cell proliferation were increased. Further, when CMECs were treated to overexpress RagD, expression of CSN2, mTOR and p-mTOR, and cell proliferation were up-regulated. Furthermore, the increase in expression of CSN2, mTOR and p-mTOR, and cell proliferation in response to Met or Lys supply was inhibited by inhibiting RagD, and those effects were reversed in the overexpression model. When CMECs were treated with RagD overexpression together with mTOR inhibition or conversely with RagD inhibition together with mTOR overexpression, results showed that the increase in expression of CSN2 and cell proliferation in response to RagD overexpression was prevented by inhibiting mTOR, and those effects were reversed by overexpressing mTOR. The interaction of RagD with subunit proteins of mTORC1 was analysed, and the result showed that RagD interacted with Raptor. CMECs were treated with Raptor inhibition, and the result showed that the increase in expression of mTOR and p-mTOR in response to RagD overexpression was inhibited by inhibiting Raptor.
In conclusion, our study showed that RagD is an important activation factor of mTORC1 in CMECs, activating AA-mediated casein synthesis and cell proliferation, potentially acting via Raptor.
The role of the protozoan parasite Toxoplasma gondii in the pathogenesis of liver disease has recently gained much interest. The aim of this study was to determine the prevalence and risk factors associated with T. gondii infection in patients with liver disease from three cities in Shandong and Henan provinces, China. A case–control study was conducted from December 2014 to November 2015 and included 1142 patients with liver disease and 1142 healthy controls. Serum samples were collected from all individuals and were examined with enzyme-linked immunosorbent assay for the presence of anti-T. gondii IgG and IgM antibodies. Information on the demographics, clinical, and lifestyle characteristics of the participants was collected from the medical records and by the use of a questionnaire. The prevalence of anti-T. gondii IgG was 19·7% in patients with liver disease compared with 12·17% in the controls. Only 13 patients had anti-T. gondii IgM antibodies compared with 12 control individuals (1·14% vs. 1·05%, respectively). The highest seroprevalence was detected in patients with liver cancer (22·13%), followed by hepatitis patients (20·86%), liver cirrhosis patients (20·42%), and steatosis patients (20%). Multivariate logistic regression analysis indicated that consumption of raw meat (odds ratio (OR) = 1·32; 95% confidence interval (CI) 1·01–1·71; P = 0·03) and source of drinking water from wells (OR = 1·56; 95% CI 1·08–2·27; P = 0·01) were independent risk factors for T. gondii infection in liver disease patients. These findings indicate that T. gondii infection is more likely to be present in patients with liver disease. Therefore, efforts should be directed toward health education of populations at high risk of T. gondii infection and measures should be taken to protect vulnerable patients with liver disease.
We investigate theoretically the field-free orientation of CO molecules induced by a single-cycle THz laser pulse train. It is shown that the molecular orientation can be obviously enhanced by applying the pulse train. The laser intensity and pulse number have some effects on the molecular orientation. The high degree of field-free molecular orientation |⟨cosθ⟩|max=0.9246 is obtained at temperature T=0 K. The variations of the maximum orientation degree with the experimentally available pulse number and peak intensity are given. Temperature T has a considerable influence on the field-free molecular orientation. The maximal field-free molecular orientation at T=0, 10, 20 and 30 K for N=14 and E0=1.8 MV/cm are |⟨cosθ⟩|max=0.9188, 0.7338, 0.6055 and 0.5154 in order, and the corresponding effective duration times of molecular orientation are Δt=0.759, 0.432, 0.297 and 0.117 ps.
Porpidia hypostictica is described as a new species; it has a white to grey-white thallus with yellow, oxidized patches near the margin, and contains hypostictic acid as the only major compound. A phylogenetic analysis is provided which is based on ITS sequences using ML and Bayesian analyses. The phylogeny supported the separation of the new species from other species. A key to all known Chinese Porpidia species is provided.
High-resolution δ18O records from a Geladaindong mountain ice core spanning the period 1477-1982 were used to investigate past temperature variations in the Yangtze River source region of the central Tibetan Plateau (TP). Annual ice-core δ18O records were positively correlated with temperature data from nearby meteorological stations, suggesting that the δ18O record represented the air temperature in the region. A generally increasing temperature trend over the past 500 years was identified, with amplified warming during the 20th century. A colder stage, spanning before the 1850s, was found to represent the Little Ice Age with colder periods occurring during the 1470s–1500s, 1580s–1660s, 1700s–20s and 1770s–1840s. Compared with other temperature records from the TP and the Northern Hemisphere, the Geladaindong ice-core record suggested that the regional climate of the central TP experienced a stronger warming trend during the 20th century than other regions. In addition, a positive relationship between the Geladaindong δ18 O values and the North Atlantic Oscillation index, combined with a wavelet analysis of δ18 O records, indicated that there was a potential atmospheric teleconnection between the North Atlantic and the central TP.
Identification of individuals within pairs of monozygotic (MZ) twins remains unresolved using common forensic DNA typing technology. For some criminal cases involving MZ twins as suspects, the twins had to be released due to inability to identify which of the pair was the perpetrator. In this study, we performed a genome-wide scan on whole blood-derived DNA from four pairs of healthy phenotypically concordant MZ twins using the methylated DNA immunoprecipitation sequencing technology to identify candidate DNA methylation markers with capacity to distinguish MZ twins within a pair. We identified 38 differential methylation regions showing within-pair methylation differences in all four MZ pairs. These are all located in CpG islands, 17 of which are promoter-associated, 17 are intergenic islands, and four are intragenic islands. Genes associated with these markers are related with cell proliferation, differentiation, and growth and development, including zinc finger proteins, PRRX2, RBBP9, or are involved in G-protein signaling, such as the regulator of G-protein signaling 16. Further validation studies on additional MZ twins are now required to evaluate the broader utility of these 38 markers for forensic use.
The current meta-analysis evaluated the association between vitamin B12 intake and blood vitamin B12 level and colorectal cancer (CRC) risk.
The PubMed and EMBASE databases were searched. A dose–response analysis was performed with generalized least squares regression, with the relative risk (RR) and 95 % CI as effect values.
The meta-analysis included seventeen studies.
A total of 10 601 patients.
The non-linear dose–response relationship between total vitamin B12 intake and CRC risk was insignificant (P=0·690), but the relationship between dietary vitamin B12 intake and CRC risk was significant (P<0·001). Every 4·5 μg/d increment in total and dietary vitamin B12 intake was inversely associated with CRC risk (total intake: RR=0·963; 95 % CI 0·928, 0·999; dietary intake: RR=0·914; 95 % CI 0·856, 0·977). The inverse association between vitamin B12 intake and CRC risk was also significant when vitamin B12 intake was over a dosage threshold, enhancing the non-linear relationship. The non-linear dose–response relationship between blood vitamin B12 level and CRC risk was insignificant (P=0·219). There was an insignificant association between every 150 pmol/l increment in blood vitamin B12 level and CRC risk (RR=1·023; 95 % CI 0·881, 1·187).
Our meta-analysis indicates that evidence supports the use of vitamin B12 for cancer prevention, especially among populations with high-dose vitamin B12 intake, and that the association between CRC risk and total vitamin B12 intake is stronger than between CRC risk and dietary vitamin B12 intake only.
Antiperovskite manganese nitrides Mn3MN (M = Zn, Ni, Cu…) have been extensively studied in the past decade due to their many interesting properties, such as negative thermal expansion. To get a better understanding of the origin of these phenomena, the information from the microscopic scale is necessary, so we performed systematic transmission electron microscopic study of Mn3Zn0.8Ni0.2N and found that the sample particle is wrapped in a thin MnO layer. The same result was also found in Mn3Zn0.5Ni0.5N and Mn3ZnN, indicating that it is a common phenomenon in this kind of compound. The presence of the MnO surface layer was also confirmed by the macroscopic XPS measurements. Our study suggests that M is easier to be lost than Mn in manganese nitrides Mn3MN (M = Zn, Ni, Cu…), and this character is much more obvious on the surface, i.e., this kind of compound has a strong surface activity. Figure 6 could best represent this manuscript.
This paper presents the preimpact configuration of a dual-arm space manipulator with a prismatic joint for capturing an object based on the momentum conservation principle. A unique precapture configuration “generalized straight-arm capture” (GSAC) is proposed based on the dual-arm space manipulator with a prismatic joint and the corresponding angular relation is obtained. The configuration satisfies GSAC and can reduce the effect of system's angular momentum caused by the impact force during the capture operation and the burden of postimpact control, so it avoids the limitation of joint velocity and actuator torque when controlling the compound (a manipulator with a prismatic joint and an object) and guarantees the stability of the system. Finally, the effectiveness of the method is demonstrated by numerical simulations.
Quantum molecular dynamic simulations have been employed to study the equation of state (EOS) of fluid helium under shock compressions. The principal Hugoniot is determined from EOS, where corrections from atomic ionization are added onto the calculated data. Our simulation results indicate that principal Hugoniot shows good agreement with gas gun and laser driven experiments, and maximum compression ratio of 5.16 is reached at 106 GPa.
Nd-doped LaVO4 crystals with the concentration up to 0.94 at.% were successfully grown by the Czochralski method. X-ray powder diffraction measurement reveals that this crystal belongs to a monoclinic space group P21/n. Refractive indices of Nd:LaVO4 have been measured with two right angle prisms for the first time to our knowledge and show that they are anisotropic. Its absorption and fluorescence spectra are also investigated. With the Judd–Ofelt theory, the optical parameters calculated are Ω2 = 2.142 × 10−20 cm2, Ω4 = 3.704 × 10−20 cm2, and Ω6 = 2.948 × 10−20 cm2. By these parameters, the absorption oscillator strengths, line strengths, transition probabilities, fluorescence branch ratios, radiative lifetime, and integrated emission cross section are also derived and compared with familiar vanadates, which show that Nd:LaVO4 is a atypical material and has potential applications in the lasers, especially in the pulsed lasers.
Studies in Western countries have repeatedly shown that women with a history of childhood sexual abuse (CSA) are at increased risk for developing major depression (MD). Would this relationship be found in China?
Three levels of CSA (non-genital, genital, and intercourse) were assessed by self-report in two groups of Han Chinese women: 1970 clinically ascertained with recurrent MD and 2597 matched controls. Diagnostic and other risk factor information was assessed at personal interview. Odds ratios (ORs) were calculated by logistic regression and regression coefficients by linear or Poisson regression.
Any form of CSA was significantly associated with recurrent MD [OR 3.26, 95% confidence interval (CI) 1.95–5.45]. This association strengthened with increasing CSA severity: non-genital (OR 2.47, 95% CI 1.17–5.23), genital (OR 2.77, 95% CI 1.32–5.83) and intercourse (OR 13.35, 95% CI 1.83–97.42). The association between any form of CSA and MD remained significant after accounting for parental history of depression, childhood emotional neglect (CEN), childhood physical abuse (CPA) and parent–child relationship. Among the depressed women, those with CSA had an earlier age of onset, longer depressive episodes and an increased risk for generalized anxiety disorder (GAD; OR 1.92, 95% CI 1.39–2.66) and dysthymia (OR 2.16, 95% CI 1.52–3.09).
In Chinese women CSA is strongly associated with MD and this association increases with greater severity of CSA. Depressed women with CSA have an earlier age of onset, longer depressive episodes and increased co-morbidity with GAD and dysthymia. Although reporting biases cannot be ruled out, our results are consistent with the hypothesis that, as in Western countries, CSA substantially increases the risk for MD in China.
Photoluminescence (PL) and X-ray Photoelectron Spectroscopy (XPS) are employed to study the Si nanocrystals formed in the thermal oxide by Si+ implantation. PL results estimate the size of nanocrystals and the concentration of Pb centers in the Si-SiO2 nanocrystal-matrix interfaces. It is shown that the size of Si nanocrystals increase with implantation dose. Increasing the dose from 1×1016 to 1×1017 Si+/cm2 shifts the size of nanocrystals from ~2 nm to ~3.5nm, while prolonging the annealing time from 1h to 2h has no effect on the position of PL peak. P and Ar implantations into the SiO2 films are also investigated to suggested that the PL peak is due to implant induced chemical changes rather than implant induced damage. XPS analysis shows that the concentration of Si nanocrystals increases with Si implantation dose. Research on the annealing dependence of the forming of Si nanocrystals suggests that 1000°C annealing produces larger amount of Si nanocrystals than 1100°C annealing.
Gut hormones play key roles in the regulation of energy homeostasis. However, little is known about the long- and short-term effects of changing dietary fat content on gut hormones. We aim to examine the effects of changing dietary fat content on plasma gut hormone concentrations in diet-induced obese (DIO) and diet-resistant (DR) rats. After inducing obesity with a high-fat (HF) diet, male Sprague–Dawley rats were divided into three groups according to their body-weight gain: DIO; DR; control (CON). The DIO and DR rats were further divided in random into two groups. One continued on a HF diet and the other switched to a low-fat (LF) diet for an additional 4 weeks. Finally, each group was randomly divided into three subgroups (n 8): fasted; fasted-refed HF; fasted-refed LF diet groups. Replacing a HF diet with a LF diet for 4 weeks resulted in less fat mass, higher fasting and post-HF plasma ghrelin concentration and lower postprandial plasma cholecystokinin concentration in the DIO and DR rats. Acute switching dietary fat resulted in significantly higher post-HF plasma ghrelin concentrations than post-LF ghrelin concentrations in the DR rats on LF diet (DRLF) and DIO rats on LF diet (DIOLF) rats, and significantly higher post-HF obestatin concentrations than post-LF obestatin concentrations in the CON, DR rats on HF diet (DRHF) and DRLF rats. Dietary fat content appears to play a role in the gut hormone profile, which may consequently influence fat mass.