We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
To save 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 saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
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 saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved 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.
Laterite could play a crucial role in soil stabilization and environmental remediation, but its internal particle interaction mechanism remains unclear. This study, based on molecular dynamics simulations, used umbrella sampling methods to measure the interaction strength between amorphous alumina and montmorillonite particles in laterite. The mechanisms were explored using differential charge density analysis and bond energy analysis. The results show that the interaction process between alumina and montmorillonite exhibited initial repulsion, then attraction, followed again by repulsion. Calcium ion-induced polarization, the negative charge on the alumina surface and the bonding strength during adsorption played key roles in this interaction. Notably, the bond energy measurement results in this study are consistent with data from other related research, validating the data’s accuracy. These findings improve our understanding of the microscopic mechanisms of laterite particle interactions, providing a scientific basis for its application in soil stabilization and environmental remediation.
A high-energy pulsed vacuum ultraviolet (VUV) solid-state laser at 177 nm with high peak power by the sixth harmonic of a neodymium-doped yttrium aluminum garnet (Nd:YAG) amplifier in a KBe2BO3F2 prism-coupled device was demonstrated. The ultraviolet (UV) pump laser is a 352 ps pulsed, spatial top-hat super-Gaussian beam at 355 nm. A high energy of a 7.12 mJ VUV laser at 177 nm is obtained with a pulse width of 255 ps, indicating a peak power of 28 MW, and the conversion efficiency is 9.42% from 355 to 177 nm. The measured results fitted well with the theoretical prediction. It is the highest pulse energy and highest peak power ever reported in the VUV range for any solid-state lasers. The high-energy, high-peak-power, and high-spatial-uniformity VUV laser is of great interest for ultra-fine machining and particle-size measurements using UV in-line Fraunhofer holography diagnostics.
Supercritical carbon dioxide (scCO2) processing has been proven as a method for preparing polymer/montmorillonite (MMT) nanocomposites with improved platelet dispersion. The influence of scCO2 processing on the shape and size of the MMT tactoid/platelet, which is of great importance to the final platelet dispersion in the polymer matrix, is scarcely reported in the literature. In the present study, the pristine MMT was first surface modified with 3-glycidoxypropyltrimethoxysilane (the grafted MMT is labeled as GMMT), and then intercalated using three kinds of intercalating agents, myristyltrimethyl-ammonium bromide (MTAB), tetradecyltrihexylphosphonium chloride (TDTHP), and ethoxyltriphenyl-phosphonium chloride (ETPC), in water or scCO2, to study the effect of intercalating agent type and intercalation method on the morphology and thermal properties of GMMT, as a part of a program devoted to the synthesis of polymer/MMT nanocomposites. The structure of intercalated GMMT was characterized by thermogravimetric analysis, X-ray powder diffraction, and scanning electron microscopy (SEM). The optimum intercalation conditions in scCO2 were established by trying a range of reaction times and pressures. The structures of intercalated GMMT obtained under optimum scCO2 conditions and water were compared. The basal spacing of GMMT intercalated in scCO2 was almost the same as that in water, and both were obviously larger than that of GMMT. The GMMT exhibited a compact spherical morphology (examined using SEM), and the surface structures (including surface morphology, surface roughness, and surface compactness) of samples intercalated in water became ‘less compact’ and the degree of the ‘compactness’ of samples intercalated in scCO2 decreased further. Whether in water or scCO2, samples intercalated with TDTHP exhibited a larger basal spacing and the extent of disorder increased compared to that for samples intercalated with MTAB. The pristine MMT was also intercalated for comparison and silane grafting was proven to contribute to the increased basal spacing and ‘less compact’ surface structure.
We present a high-energy, hundred-picosecond (ps) pulsed mid-ultraviolet solid-state laser at 266 nm by a direct second harmonic generation (SHG) in a barium borate (BaB2O4, BBO) nonlinear crystal. The green pump source is a 710 mJ, 330 ps pulsed laser at a wavelength of 532 nm with a repetition rate of 1 Hz. Under a green pump energy of 710 mJ, a maximum output energy of 253.3 mJ at 266 nm is achieved with 250 ps pulse duration resulting in a peak power of more than 1 GW, corresponding to an SHG conversion efficiency of 35.7% from 532 to 266 nm. The experimental data were well consistent with the theoretical prediction. To the best of our knowledge, this laser exhibits both the highest output energy and highest peak power ever achieved in a hundred-ps/ps regime at 266 nm for BBO-SHG.
Despite increasing knowledge on the neuroimaging patterns of eating disorder (ED) symptoms in non-clinical populations, studies using whole-brain machine learning to identify connectome-based neuromarkers of ED symptomatology are absent. This study examined the association of connectivity within and between large-scale functional networks with specific symptomatic behaviors and cognitions using connectome-based predictive modeling (CPM).
Methods
CPM with ten-fold cross-validation was carried out to probe functional networks that were predictive of ED-associated symptomatology, including body image concerns, binge eating, and compensatory behaviors, within the discovery sample of 660 participants. The predictive ability of the identified networks was validated using an independent sample of 821 participants.
Results
The connectivity predictive of body image concerns was identified within and between networks implicated in cognitive control (frontoparietal and medial frontal), reward sensitivity (subcortical), and visual perception (visual). Crucially, the set of connections in the positive network related to body image concerns identified in one sample was generalized to predict body image concerns in an independent sample, suggesting the replicability of this effect.
Conclusions
These findings point to the feasibility of using the functional connectome to predict ED symptomatology in the general population and provide the first evidence that functional interplay among distributed networks predicts body shape/weight concerns.
The relationship of a diet low in fibre with mortality has not been evaluated. This study aims to assess the burden of non-communicable chronic diseases (NCD) attributable to a diet low in fibre globally from 1990 to 2019.
Design:
All data were from the Global Burden of Disease (GBD) Study 2019, in which the mortality, disability-adjusted life-years (DALY) and years lived with disability (YLD) were estimated with Bayesian geospatial regression using data at global, regional and country level acquired from an extensively systematic review.
Setting:
All data sourced from the GBD Study 2019.
Participants:
All age groups for both sexes.
Results:
The age-standardised mortality rates (ASMR) declined in most GBD regions; however, in Southern sub-Saharan Africa, the ASMR increased from 4·07 (95 % uncertainty interval (UI) (2·08, 6·34)) to 4·60 (95 % UI (2·59, 6·90)), and in Central sub-Saharan Africa, the ASMR increased from 7·46 (95 % UI (3·64, 11·90)) to 9·34 (95 % UI (4·69, 15·25)). Uptrends were observed in the age-standardised YLD rates attributable to a diet low in fibre in a number of GBD regions. The burden caused by diabetes mellitus increased in Central Asia, Southern sub-Saharan Africa and Eastern Europe.
Conclusions:
The burdens of disease attributable to a diet low in fibre in Southern sub-Saharan Africa and Central sub-Saharan Africa and the age-standardised YLD rates in a number of GBD regions increased from 1990 to 2019. Therefore, greater efforts are needed to reduce the disease burden caused by a diet low in fibre.
This study presents an under-actuated snake arm maintainer (SAM) for complex and extreme environments such as nuclear power plants. The structure adopts the layered cable drive principle, whereby a single drive layer drives multiple joints. This design significantly reduces the complexity of the control system while increasing the spatial curvature. The traction of multiple wire ropes with a composite capstan drives the synchronous angular motion of several adjacent joints. By changing the number of joints in the single driver layer of the snake arm, the arm can be adapted to various complex environments. The trajectory planning and trajectory tracking motion control methods of the under-actuated SAM are established based on the improved backbone method and the variable rod length algorithm. Finally, a 10-joint prototype with an arm length of 2300 mm is designed for nuclear reactor maintenance. Trajectory experiments confirmed the rationality of the under-actuated SAM, the correctness of the inverse kinematics, and the effectiveness of the motion control methods.
NaY zeolite was synthesized from kaolin/dimethyl sulfoxide (DMSO) intercalation composites using an in situ crystallization technique. The effects of the intercalation ratios and the amounts of the kaolin/DMSO intercalation composite on the synthesis of an NaY zeolite molecular sieve were studied. The samples were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, differential thermal analysis, N2 adsorption–desorption and scanning electron microscopy. In the in situ synthesis system, when the kaolin/DMSO intercalation composite was added, pure NaY zeolite was formed. By increasing the amount of kaolin/DMSO intercalation composite added, the crystallinity of the samples increased, and after reaching the maximum amount of kaolin/DMSO intercalation composite added, the crystallinity decreased with further increases of the amount of kaolin/DMSO intercalation composite added. To higher intercalation ratio, the crystallinity can be greatly improved at the lower addition content. At an intercalation ratio of 84%, the added amount of kaolin/DMSO intercalation composite was 2.5% and the crystallinity of the NaY zeolite molecular sieve reached a maximum value of 45%. At intercalation ratios of 55% and 22%, the amount of kaolin/DMSO intercalation composite added was 15% and the crystallinities of the NaY zeolite molecular sieves were 44% and 47%, respectively. The NaY zeolite has good thermal stability and a particle diameter of ~0.5 μm. The Brunauer–Emmett–Teller (BET) specific surface area and pore volume of the sample were 519 m2 g–1 and 0.355 cm3 g–1, respectively.
We aimed to examine whether baseline neutrophil counts affected the risk of new-onset proteinuria in hypertensive patients, and, if so, whether folic acid treatment is particularly effective in proteinuria prevention in such a setting. A total of 8208 eligible participants without proteinuria at baseline were analysed from the renal substudy of the China Stroke Primary Prevention Trial. Participants were randomised to receive a double-blind daily treatment of 10 mg of enalapril and 0·8 mg of folic acid (n 4101) or 10 mg of enalapril only (n 4107). The primary outcome was new-onset proteinuria, defined as a urine dipstick reading of ≥1+ at the exit visit. The mean age of the participants was 59·5 (sd, 7·4) years, 3088 (37·6 %) of the participants were male. The median treatment duration was 4·4 years. In the enalapril-only group, a significantly higher risk of new-onset proteinuria was found among participants with higher neutrophil counts (quintile 5; ≥4·8 × 109/l, OR 1·44; 95 % CI 1·00, 2·06), compared with those in quintiles 1–4. For those with enalapril and folic acid treatment, compared with the enalapril-only group, the new-onset proteinuria risk was reduced from 5·2 to 2·8 % (OR 0·49; 95 % CI 0·29, 0·82) among participants with higher neutrophil counts (≥4·8 × 109/l), whereas there was no significant effect among those with neutrophil counts <4·8 × 109/l. In summary, among hypertensive patients, those with higher neutrophil counts had increased risk of new-onset proteinuria, and this risk was reduced by 51 % with folic acid treatment.
Major depressive disorder (MDD) is a common debilitating disorder characterized by impaired spontaneous brain activity, yet little is known about its alterations in dynamic properties and the molecular mechanisms associated with these changes.
Methods
Based on the resting-state functional MRI data of 65 first-episode, treatment-naïve patients with MDD and 66 healthy controls, we compared dynamic regional homogeneity (dReHo) of spontaneous brain activity between the two groups, and we investigated gene expression profiles associated with dReHo alterations in MDD by leveraging transcriptional data from the Allen Human Brain Atlas and weighted gene co-expression network analysis.
Results
Compared with healthy controls, patients with MDD consistently showed reduced dReHo in both fusiform gyri and in the right temporal pole and hippocampus. The expression profiles of 16 gene modules were correlated with dReHo alterations in MDD. These gene modules were enriched for various biological process terms, including immune, synaptic signalling, ion channels, mitochondrial function and protein metabolism, and were preferentially expressed in different cell types.
Conclusions
Patients with MDD have reduced dReHo in brain areas associated with emotional and cognitive regulation, and these changes may be related to complex polygenetic and polypathway mechanisms.
Shifts in the maternal gut microbiota have been implicated in the development of gestational diabetes mellitus (GDM). Understanding the interaction between gut microbiota and host glucose metabolism will provide a new target of prediction and treatment. In this nested case-control study, we aimed to investigate the causal effects of gut microbiota from GDM patients on the glucose metabolism of germ-free (GF) mice. Stool and peripheral blood samples, as well as clinical information, were collected from 45 GDM patients and 45 healthy controls (matched by age and prepregnancy body mass index (BMI)) in the first and second trimester. Gut microbiota profiles were explored by next-generation sequencing of the 16S rRNA gene, and inflammatory factors in peripheral blood were analyzed by enzyme-linked immunosorbent assay. Fecal samples from GDM and non-GDM donors were transferred to GF mice. The gut microbiota of women with GDM showed reduced richness, specifically decreased Bacteroides and Akkermansia, as well as increased Faecalibacterium. The relative abundance of Akkermansia was negatively associated with blood glucose levels, and the relative abundance of Faecalibacterium was positively related to inflammatory factor concentrations. The transfer of fecal microbiota from GDM and non-GDM donors to GF mice resulted in different gut microbiota colonization patterns, and hyperglycemia was induced in mice that received GDM donor microbiota. These results suggested that the shifting pattern of gut microbiota in GDM patients contributed to disease pathogenesis.
Hubei province in China has had the most confirmed coronavirus disease 2019 (COVID-19) cases and has reported sustained transmission of the disease. Although Lu'an city is adjacent to Hubei province, its community transmission was blocked at the early stage, and the impact of the epidemic was limited. Therefore, we summarised the overall characteristics of the entire epidemic course in Lu'an to help cities with a few imported cases better contain the epidemic. A total of 69 confirmed COVID-19 cases and 11 asymptomatic carriers were identified in Lu'an during the epidemic from 12 January to 21 February 2020. Fifty-two (65.0%) cases were male, and the median age was 40 years. On admission, 56.5% of cases had a fever as the initial symptom, and pneumonia was present in 89.9% of cases. The mean serial interval and the mean duration of hospitalisation were 6.5 days (95% CI: 4.8–8.2) and 18.2 days (95% CI: 16.8–19.5), respectively. A total of 16 clusters involving 60 cases (17 first-generation cases and 43 secondary cases) were reported during the epidemic. We observed that only 18.9% (7/37) index cases resulted in community transmission during the epidemic in Lu'an, indicating that the scale of the epidemic was limited to a low level in Lu'an city. An asymptomatic carrier caused the largest cluster, involving 13 cases. Spread of COVID-19 by asymptomatic carriers represents an enormous challenge for countries responding to the pandemic.
We aimed to evaluate the relationship of plasma Mg with the risk of new-onset hyperuricaemia and examine any possible effect modifiers in hypertensive patients. This is a post hoc analysis of the Uric acid (UA) Sub-study of the China Stroke Primary Prevention Trial (CSPPT). A total of 1685 participants were included in the present study. The main outcome was new-onset hyperuricaemia defined as a UA concentration ≥417 μmol/l in men or ≥357 μmol/l in women. The secondary outcome was a change in UA concentration defined as UA at the exit visit minus that at baseline. During a median follow-up duration of 4·3 years, new-onset hyperuricaemia occurred in 290 (17·2 %) participants. There was a significantly inverse relation of plasma Mg with the risk of new-onset hyperuricaemia (per sd increment; OR 0·85; 95 % CI 0·74, 0·99) and change in UA levels (per sd increment; β −3·96 μmol/l; 95 % CI −7·14, −0·79). Consistently, when plasma Mg was analysed as tertiles, a significantly lower risk of new-onset hyperuricaemia (OR 0·67; 95 % CI 0·48, 0·95) and less increase in UA levels (β −8·35 μmol/l; 95 % CI −16·12, −0·58) were found among participants in tertile 3 (≥885·5 μmol/l) compared with those in tertile 1 (<818·9 μmol/l). Similar trends were found in males and females. Higher plasma Mg levels were associated with a decreased risk of new-onset hyperuricaemia in hypertensive adults.
To examine adherence to a Mediterranean-like diet at age 9–10 years in relation to onset of breast development (thelarche) and first menstruation (menarche).
Design:
We evaluated the associations of adherence to a Mediterranean-like diet (measured by an adapted Mediterranean-like Diet Score, range 0–9) with thelarche at baseline, age at thelarche and time to menarche. Data were collected at baseline during a clinic visit, complemented with a mailed questionnaire and three 24 hour telephone dietary recalls, followed by annual follow-up questionnaires. Multivariable Poisson regression, linear regression and Cox proportional hazards regression were used to evaluate timing of pubertal development in relation to diet adherence.
Setting:
New Jersey, USA.
Participants:
Girls aged 9 or 10 years at baseline (2006–2014, n 202).
Results:
High Mediterranean-like diet adherence (score 6–9) was associated with a lower prevalence of thelarche at baseline compared with low adherence (score 0–3; prevalence ratio = 0·65, 95 % CI 0·48, 0·90). This may have been driven by consumption of fish and non-fat/low-fat dairy. Our models also suggested a later age at thelarche with higher Mediterranean-like diet adherence. Girls with higher Mediterranean-like diet adherence had significantly longer time to menarche (hazard ratio = 0·45, 95 % CI 0·28, 0·71 for high v. low adherence). Further analysis suggested this may have been driven by vegetable and non-fat/low-fat dairy consumption.
Conclusions:
Consuming a Mediterranean-like diet may be associated with older age at thelarche and menarche. Further research is necessary to confirm our findings in other US paediatric populations and elucidate the mechanism through which Mediterranean-like diet may influence puberty timing.
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).
Genome-wide association studies (GWAS) have consistently revealed that a variant of microRNA 137 (MIR137) shows a quite significant association with schizophrenia. Identifying the network of genes regulated by MIR137 could provide insights into the biological processes underlying schizophrenia. In addition, DLPFC functional connectivity, a robust correlate of MIR137, may provide plausible endophenotypes. However, the regulatory role of the MIR137 gene network in the disrupted functional connectivity remains unclear. Here, we tested the effects of the MIR137 regulated genes on the risk for schizophrenia and DLPFC functional connectivity.
Methods
To evaluate the additive effects of the MIR137 regulated genes (N = 1274), we calculated a MIR137 polygenic risk score (PRS) for schizophrenia and tested its association with the risk for schizophrenia in the genomic data of a Han Chinese population that included schizophrenia patients (N = 589) and normal controls (N = 575). We then investigated the association between MIR137 PRS and DLPFC functional connectivity in two independent young healthy cohorts (N = 356 and N = 314).
Results
We found that the MIR137 PRS successfully captured the differences in genetic structure between the patients and controls, but the single gene MIR137 did not. We then consistently found that a higher MIR137 PRS was correlated with lower functional connectivities between the DLPFC and both the superior parietal cortex and the inferior temporal cortex in two independent cohorts.
Conclusion
The findings suggested that these two functional connectivities of the DLPFC could be important endophenotypes linking the MIR137-regulated genetic structure to schizophrenia.
Novel NiMoO4-integrated electrode materials were successfully prepared by solvothermal method using Na2MoO4·2H2O and NiSO4·6H2O as main raw materials, water, and ethanol as solvents. The morphology, phase, and structure of the as-prepared materials were characterized by SEM, XRD, Raman, and FT-IR. The electrochemical properties of the materials in supercapacitors were investigated by cyclic voltammetry, constant current charge–discharge, and electrochemical impedance spectroscopy techniques. The effects of volume ratio of water to ethanol (W/E) in solvent on the properties of the product were studied. The results show that the pure phase monoclinic crystal NiMoO4 product can be obtained when the W/E is 2:1. The diameter and length are 0.1–0.3 µm and approximately 3 µm, respectively. As an active material for supercapacitor, the NiMoO4 nanorods material delivered a discharge specific capacitance of 672, 498, and 396 F/g at a current density of 4, 7, and 10 A/g, respectively. The discharge specific capacitance slightly decreased from 815 to 588 F/g with a retention of 72% after 1000 cycles at a current density of 1 A/g. With these superior capacitance properties, the novel NiMoO4 integrated electrode materials could be considered as promising material for supercapacitors.
Compared with commercial polyolefin membranes, polyacrylonitrile (PAN) membrane prepared by electrostatic spinning has higher porosity, electrolyte uptake, thermal stability, and lithium-ion conductivity, etc. However, poor mechanical performance has largely limited the application of electrospun PAN separators. In this study, PAN/polyimide (PI) composite membrane is prepared by electrostatic spinning to improve the mechanical and electrochemical performances. Scanning electron microscopy, thermal analysis method, and electrochemical methods were used for evaluation of the electrospun composite membrane. The results show that the composite membrane possesses good thermal stability and exhibits better mechanical performance than pristine PAN membrane (increasing by 1.1 times in tension strength). The addition of PI can increase porosity and fluid absorption rate obviously. In addition, the composite membrane has high ionic conductivity (18.77 × 10−4 S/cm), wide electrochemical window (about 4.0 V), and excellent cycling performance. It can retain a discharge specific capacity of 153 mA h/g even after 50 cycles at 0.5 C. The electrospun PAN/PI membrane may be a promising candidate for lithium-ion battery separators.
We sought to examine the potential modifiers in the association between long-term low-dose folic acid supplementation and the reduction of serum total homocysteine (tHcy) among hypertensive patients, using data from the China Stroke Primary Prevention Trial (CSPPT). This analysis included 16 867 participants who had complete data on tHcy measurements at both the baseline and exit visit. After a median treatment period of 4·5 years, folic acid treatment significantly reduced the tHcy levels by 1·6 μmol/l (95 % CI 1·4, 1·8). More importantly, after adjustment for baseline tHcy and other important covariates, a greater degree of tHcy reduction was observed in certain subgroups: males, the methylenetetrahydrofolate reductase (MTHFR) 677TT genotype, higher baseline tHcy levels (≥12·5 (median) v. <12·5 μmol/l), lower folate levels (<8·0 (median) v. ≥8·0 ng/ml), estimated glomerular filtration rate (eGFR) <60 ml/min per 1·73 m2 (v. 60–<90 and ≥90 ml/min per 1·73 m2), ever smokers and concomitant use of diuretics (P for all interactions <0·05). The degree of tHcy reduction associated with long-term folic acid supplementation can be significantly affected by sex, MTHFR C677T genotypes, baseline folate, tHcy, eGFR levels and smoking status.
High-entropy ceramic (HEC) films refer to the carbide, boride, oxide, or nitride films of the high-entropy alloy, which have potential applications under high temperatures. In this study, we fabricated the HEC NbTiAlSiZrNx films using magnetron sputtering under various deposition atmospheres. The phase structure evolution and the mechanical properties of three HEC films under high temperatures were investigated. The HEC films demonstrated good thermal stability as well as high hardness. After annealing for 24 h at 700 °C, the films remained in an amorphous phase without obvious crystallization, and the hardness of the films declined. Nanocrystallizations occurred in films deposited at a nitrogen flow rate of 4 sccm and 8 sccm after annealing for 30 min at 900 °C and exhibited an face-centered cubic structure. HEC NbTiAlSiZrNx films have potential applications as protective coatings under high temperatures.