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Many particles, whether passive or active, possess elongated shapes. When these particles settle or swim in shear flows, they often form regions of accumulation and depletion. Additionally, the density contrast between the particles and the fluid can further alter the flow by increasing the local suspension density, resulting in a two-way buoyancy–flow coupling mechanism. This study investigates the buoyancy–flow coupled dispersion of active spheroids, examining the effects of elongation, orientation-dependent settling and gyrotaxis in a vertical pipe subjected to either downwards or upwards discharge. While the concentration and velocity profiles of passive settling spheroids and spherical gyrotactic swimmers can be analysed similarly to a recent study, notable differences in dispersion characteristics emerge due to different streamline-crossing mechanisms. For suspensions of elongated swimmers, the interplay between orientation-dependent settling, gyrotaxis-induced accumulation and shear-induced trapping results in distinct concentration and velocity distributions compared to those of neutrally buoyant particles and extremely dilute suspensions with negligible coupling effect. These differences further impact drift velocity, dispersivity, and the time elapsed to steady dispersion under varying flow rates. Interestingly, low-shear trapping of non-settling elongated swimmers around the centreline, commonly observed in planar Poiseuille flow, is absent in the vertical pipe due to the change of confinement from reflectional to rotational symmetry. However, elongated settling swimmers show a non-trivial concentration response to strong downwelling discharge. This phenomenon, linked to the centreline accumulation of passive settling spheroids, bears similarities to low-shear trapping observed in planar Poiseuille flow.
The study aims were to present in vitro susceptibilities of clinical isolates from Gram-negative bacteria bloodstream infections (GNBSI) collected in China. GNBSI isolates were collected from 18 tertiary hospitals in 7 regions of China from 2018 to 2020. Minimum inhibitory concentrations were assessed using a Trek Diagnostic System. Susceptibility was determined using CLSI broth microdilution, and breakpoints were interpreted using CLSI M100 (2021). A total of 1,815 GNBSI strains were collected, with E. coli (42.4%) and Klebsiella pneumoniae (28.6%) being the most prevalent species, followed by P. aeruginosa (6.7%). Susceptibility analyses revealed low susceptibilities (<40%) of ESBL-producing E. coli and K. pneumonia to third-/fourth-generation cephalosporins, monobactamases, and fluoroquinolones. High susceptibilities to colistin (95.0%) and amikacin (81.3%) were found for K. pneumoniae, while Acinetobacter baumannii exhibited a high susceptibility (99.2%) to colistin but a low susceptibility to other antimicrobials (<27.5%). Isolates from ICUs displayed lower drug susceptibility rates of K. pneumoniae and A. baumannii than isolates from non-ICUs (all P < 0.05). Carbapenem-resistant and ESBL-producing K. pneumoniae detection was different across regions (both P < 0.05). E. coli and K. pneumoniae were major contributors to GNBSI, while A. baumannii exhibited severe drug resistance in isolates obtained from ICU departments.
River terraces serve as excellent indicators of the landform evolution of the Guizhou Plateau. This paper presents the results of terrace investigation and optically stimulated luminescence (OSL) dating focused on five sections along the Liujiang River of the southeastern Guizhou Plateau. The OSL ages of the terraces range from 0.21 ± 0.02 to 16.0 ± 1.4 ka for the first terraces (T1) and from 3.5 ± 0.3 to 26.5 ± 3.3 ka for the second terraces (T2), which are much younger than those of other basins on the Guizhou Plateau. These ages, considered in tandem with the results of previous investigations, enhance our understanding of the fluvial landform evolution of the Guizhou Plateau since the Late Pleistocene. On the Guizhou Plateau platform, terraces are considered to be the response of river evolution to tectonic uplift, indicating a relatively slow geomorphic process. In the slope zone, climate change has had a significant impact on the fluvial landform processes, driving the formation of the younger terraces along the Liujiang River. In the platform–slope transition zone, the evolution of terraces was driven by both tectonic uplift and climate change, where the landform processes were dominated by strong headward erosion.
Depression has been linked to disruptions in resting-state networks (RSNs). However, inconsistent findings on RSN disruptions, with variations in reported connectivity within and between RSNs, complicate the understanding of the neurobiological mechanisms underlying depression.
Methods
A systematic literature search of PubMed and Web of Science identified studies that employed resting-state functional magnetic resonance imaging (fMRI) to explore RSN changes in depression. Studies using seed-based functional connectivity analysis or independent component analysis were included, and coordinate-based meta-analyses were performed to evaluate alterations in RSN connectivity both within and between networks.
Results
A total of 58 studies were included, comprising 2321 patients with depression and 2197 healthy controls. The meta-analysis revealed significant alterations in RSN connectivity, both within and between networks, in patients with depression compared with healthy controls. Specifically, within-network changes included both increased and decreased connectivity in the default mode network (DMN) and increased connectivity in the frontoparietal network (FPN). Between-network findings showed increased DMN–FPN and limbic network (LN)–DMN connectivity, decreased DMN–somatomotor network and LN–FPN connectivity, and varied ventral attention network (VAN)–dorsal attentional network (DAN) connectivity. Additionally, a positive correlation was found between illness duration and increased connectivity between the VAN and DAN.
Conclusions
These findings not only provide a comprehensive characterization of RSN disruptions in depression but also enhance our understanding of the neurobiological mechanisms underlying depression.
This study aimed to investigate the intake of dairy products during pregnancy in women with gestational diabetes mellitus (GDM) and its impacts on neonatal birth weight and pregnancy outcomes. A total of 386 women with GDM during the second trimester pregnancy participated in this prospective cohort study. We evaluated dairy products intake through the FFQ. Pregnancy outcomes were obtained from the delivery data. Participants were divided into insufficient and sufficient intake of milk and dairy products groups (< 300 g/d and ≥ 300 g/d, respectively). The average intake of dairy products during the second trimester pregnancy in women with GDM was 317·8 ± 179·5 g/d, and the total energy intake was 1635·4 ± 708·7 kcal/d. However, 76·68 % of them did not meet the recommended total energy intake of women with GDM. After adjusting for confounding factors, women with GDM who consumed ≥ 300 g/d of dairy products had an average reduction in birth weight of 93·1 g compared with women who consumed < 300 g/d of dairy products (95 % CI −171·343, −14·927). Women with GDM in sufficient intake group was also associated with lower risk of macrosomia (95 % CI 0·043, 0·695) and caesarean section (95 % CI 0·387, 0·933) and not related to low birth weight infant (95 % CI 0·617, 14·502) and preterm birth (95 % CI 0·186, 1·510) when compared with participants in insufficient intake group. Under the premise of insufficient total energy intake, the intake of dairy products during the second trimester pregnancy in women with GDM might be related to the decrease of neonatal birth weight.
Bronze mou vessels appear in Shu tombs in south-west China during the Eastern Zhou period (c. 771–256 BC). Examination of these vessels reveals major changes in the supply of metal and alloying technology in the Shu State, throwing new light on the social impact of the Qin conquest and later unification of China.
The emotion regulation network (ERN) in the brain provides a framework for understanding the neuropathology of affective disorders. Although previous neuroimaging studies have investigated the neurobiological correlates of the ERN in major depressive disorder (MDD), whether patients with MDD exhibit abnormal functional connectivity (FC) patterns in the ERN and whether the abnormal FC in the ERN can serve as a therapeutic response signature remain unclear.
Methods
A large functional magnetic resonance imaging dataset comprising 709 patients with MDD and 725 healthy controls (HCs) recruited across five sites was analyzed. Using a seed-based FC approach, we first investigated the group differences in whole-brain resting-state FC of the 14 ERN seeds between participants with and without MDD. Furthermore, an independent sample (45 MDD patients) was used to evaluate the relationship between the aforementioned abnormal FC in the ERN and symptom improvement after 8 weeks of antidepressant monotherapy.
Results
Compared to the HCs, patients with MDD exhibited aberrant FC between 7 ERN seeds and several cortical and subcortical areas, including the bilateral middle temporal gyrus, bilateral occipital gyrus, right thalamus, calcarine cortex, middle frontal gyrus, and the bilateral superior temporal gyrus. In an independent sample, these aberrant FCs in the ERN were negatively correlated with the reduction rate of the HAMD17 score among MDD patients.
Conclusions
These results might extend our understanding of the neurobiological underpinnings underlying unadaptable or inflexible emotional processing in MDD patients and help to elucidate the mechanisms of therapeutic response.
Rhopalosiphum padi is an important grain pest, causing severe losses during crop production. As a systemic insecticide, flonicamid can control piercing-sucking pests efficiently. In our study, the lethal effects of flonicamid on the biological traits of R. padi were investigated via a life table approach. Flonicamid is highly efficiently toxic to R. padi, with an LC50 of 9.068 mg L−1. The adult longevity and fecundity of the R. padi F0 generation were markedly reduced under the LC25 and LC50 concentrations of flonicamid exposure. In addition, negative transgenerational effects on R. padi were observed under exposure to lethal concentrations of flonicamid, with noticeable decreases in the reproductive period, adult longevity, total longevity, and total fecundity of the F1 generation under the LC25 concentration of flonicamid. Furthermore, the third nymph stage (N3), preadult stage, duration of the adult pre-reproductive period, duration of the total pre-reproductive period, reproductive period, adult longevity, total longevity, and total fecundity of the F1 generation were significantly lower under treatment with the LC50 concentration of flonicamid. The life table parameters were subsequently analysed, revealing that the intrinsic rate of increase (rm) and the net reproductive rate (R0) were significantly lower but that the finite rate of increase (λ) and the mean generation time (T) were not significantly different under the LC25 and LC50 concentrations of flonicamid. These data are beneficial for grain aphid control and are critical for exploring the role of flonicamid in the integrated management of this key pest.
An advanced deformable Kirkpatrick–Baez (K-B) mirror system was developed, equipped with high-speed piezoelectric actuators, and designed to induce beam decoherence and significantly enhance the quality of X-ray imaging by minimizing undesirable speckles in synchrotron radiation or free-electron laser facilities. Each individual mirror is engineered with 36 independent piezoelectric actuators that operate in a randomized manner, orchestrating the mirror surface to oscillate at a high frequency up to 100 kHz. Through in situ imaging single-slit diffraction measurement, it has been demonstrated that this high-frequency-vibration mirror system is pivotal in disrupting the coherent nature, thereby diminishing speckle formation. The impact of the K-B mirror system is profound, with the capability to reduce the image contrast to as low as 0.04, signifying a substantial reduction in speckle visibility. Moreover, the coherence of the X-ray beam is significantly lowered from an initial value exceeding 80% to 13%.
Glaciers play a crucial role in the Asian Water Tower, underscoring the necessity of accurately assessing their mass balance and ice volume to evaluate their significance as sustainable freshwater resources. In this study, we analyzed ground-penetrating radar (GPR) measurements from a 2020 survey of the Xiao Dongkemadi Glacier (XDG) to determine ice thickness, and we extended the glacier’s volume-change record to 2020 by employing multi-source remote-sensing data. Our findings show that the GPR-derived mean ice thickness of XDG in 2020 was 54.78 ± 3.69 m, corresponding to an ice volume of 0.0811 ± 0.0056 km3. From 1969 to 2020, the geodetic mass balance was −0.19 ± 0.02 m w.e. a−1, and the glacier experienced area and ice volume losses of 16.38 ± 4.66% and 31.01 ± 4.59%, respectively. The long-term mass-balance reconstruction reveals weak fluctuations occurred from 1967 to 1993 and that overall mass losses have occurred since 1994. This ongoing shrinkage and ice loss are mainly associated with the temperature increases in the warm season since the 1960s. If the climate trend across the central Tibetan Plateau follows to the SSP585 scenario, then XDG is at risk of disappearing by the end of the century.
Palygorskite (Pal) shows great potential for physical, chemical and biological uses due to its colloidal, catalytic and adsorption properties. Pal mines, however, are facing the challenge of low-grade materials (5–15%), making it difficult to use Pal in emerging fields such as new materials, environmental protection and health. Therefore, there is an urgent need to develop an efficient method for separating and purifying Pal to obtain high purity levels. Hence, we have developed a dispersant-assisted rotating liquid film reactor separation strategy based on sodium hexametaphosphate as the dispersant. This strategy utilizes the double electron layer of Pal and the density difference between impurities to achieve effective disaggregation and purification of Pal bundles through the promotion of repulsive driving effects. Under optimal conditions, the purity of Pal can be increased from less than 10% to over 80%. This research presents a novel approach to the efficient refining of low-grade Pal. The crudely purified Pal’s adsorption capacity for methylene blue increased from 84.2 to 256.4 mg g–1.
The aim of this study was to investigate the antioxidant effect of alpha-lipoic acid (α-LA) in dairy cows and its metabolic mechanism. Thirty Holstein cows weighing 550 ± 25 kg, 200 ± 15 days of lactation and calving 2–3 times were randomly divided into three groups, ten cows in each group. Different doses of α-LA were added based on body weight: 0 (CTL), 30 (LA-L) and 60 (LA-H) mg/kg per head per day; 7 days adaptation period, 30 days formal period. Milk production was recorded daily during the test period. Milk and blood samples were collected on the last day. ELISA kits and automatic biochemical analyser were used to detect the indicators in blood; serum metabolites were detected and analysed by non-target metabolomics. The results of the study showed that the addition of α-LA significantly increased milk yield; blood concentrations for HDL, triglyceride, cortisol and triiodothyronine were significantly elevated; and levels of glutathione reductase and nitric oxide synthase were significantly reduced in LA-L group as compared to CTL group. The concentrations of IL-1β, IL-2, TNF-α, IgG and IgA were significantly higher after supplementation with α-LA. Metabolomics analysis revealed 13 and 15 differential metabolites each in positive or negative modes. Methylmalonic acid levels were significantly higher following α-LA supplementation compared to CTL group, as were D-lactose, D-maltose and oleanolic acid levels in LA-L group. In summary, α-LA can enhance milk production, improve antioxidant capacity and immunity, and is more beneficial for animal production and economic benefits at 30 mg/kg.
Our study aimed to develop and validate a nomogram to assess talaromycosis risk in hospitalized HIV-positive patients. Prediction models were built using data from a multicentre retrospective cohort study in China. On the basis of the inclusion and exclusion criteria, we collected data from 1564 hospitalized HIV-positive patients in four hospitals from 2010 to 2019. Inpatients were randomly assigned to the training or validation group at a 7:3 ratio. To identify the potential risk factors for talaromycosis in HIV-infected patients, univariate and multivariate logistic regression analyses were conducted. Through multivariate logistic regression, we determined ten variables that were independent risk factors for talaromycosis in HIV-infected individuals. A nomogram was developed following the findings of the multivariate logistic regression analysis. For user convenience, a web-based nomogram calculator was also created. The nomogram demonstrated excellent discrimination in both the training and validation groups [area under the ROC curve (AUC) = 0.883 vs. 0.889] and good calibration. The results of the clinical impact curve (CIC) analysis and decision curve analysis (DCA) confirmed the clinical utility of the model. Clinicians will benefit from this simple, practical, and quantitative strategy to predict talaromycosis risk in HIV-infected patients and can implement appropriate interventions accordingly.
The self-generated magnetic field in three-dimensional (3-D) single-mode ablative Rayleigh–Taylor instability (ARTI) relevant to the acceleration phase of a direct-drive inertial confinement fusion (ICF) implosion is investigated. It is found that stronger magnetic fields up to a few thousand teslas can be generated by 3-D ARTI rather than by its two-dimensional (2-D) counterpart. The Nernst effects significantly alter the magnetic field convection and amplify the magnetic fields. The magnetic field of thousands of teslas yields the Hall parameter of the order of unity, leading to profound magnetized heat flux modification. While the magnetic field significantly accelerates the bubble growth in the short-wavelength 2-D modes through modifying the heat fluxes, the magnetic field mostly accelerates the spike growth but has little influence on the bubble growth in 3-D ARTI. The accelerated growth of spikes in 3-D ARTI is expected to enhance material mixing and degrade ICF implosion performance. This work is focused on a regime relevant to direct-drive ICF parameters at the National Ignition Facility, and it also covers a range of key parameters that are relevant to other ICF designs and hydrodynamic/astrophysical scenarios.
To construct an evidence-based practice programme for the nutrition management of older adults in nursing homes. The programme will provide a basis for improving or solving the nutrition management problems of older adults in nursing homes.
Design:
The study is based on guideline evidence and Delphi method. The evidence was comprehensively searched, assessed and summarized, and the best evidence and a preliminary programme for nutrition management of older adults in nursing homes were aggregated. Then, the Delphi method was used to assess the applicability of the preliminary programme and the obstacle factors to modify, supplement and improve the nutrition management programme.
Setting:
Baseline survey data were collected from three nursing homes in Ningxia, China, and guideline evidence was obtained through systematic searches of the Cochrane Library, PubMed and other scientific databases, as well as relevant official websites.
Participants:
A total of 350 older adults residing nursing homes and 160 nurses participated in the baseline survey. To ensure the programme’s applicability and identify potential implementation obstacles, fifteen experts from local grade A hospitals, nursing homes and community health centres were consulted for review.
Results:
A fourteen-item, fifty-six-best-evidence nutrition management programme for older adults in nursing homes was developed based on five guideline evidences and baseline survey findings.
Conclusions:
This is a systematic and comprehensive nutritional management programme for older adults in nursing homes based on guideline evidence, which can provide a standardised basis for the implementation of scientific nutritional management in nursing homes in Ningxia. Managers should promote the translation of evidence into practice in accordance with the specific circumstances of individual nursing homes.
Rumen microbial biohydrogenation (RBH) is the major factor responsible for the bovine milk rich in saturated fatty acids (FAs). Here, we evaluated the effects of nutritional manipulation of ruminal propionogenesis and methanogenesis, two primary hydrogen sinks, on the RBH and milk FA profiles in vivo and in vitro using three propionogenesis enhancers (fumarate [FUM], biotin and monensin) and one methanogenesis inhibitor (N-[2-(nitrooxy)ethyl]-3-pyridinecarboxamide [NPD]). The in vivo results showed that inclusion of FUM in lactating dairy goat diet could protect dietary unsaturated FAs against RBH with increased proportions of C18:2n − 6 (by 33.5%), C18:3n − 3 (by 38.1%) and RBH intermediates (e.g. trans-10 C18:1 and trans-11 C18:1) in rumen contents. Additionally, FUM supplementation increased the milk Δ9 desaturase index (by 15.5%) with higher cis-9 monounsaturated FAs in the milk. As a result, FUM increased the proportions of polyunsaturated and monounsaturated FAs in the milk with lower atherogenicity index (by −15.3%) and thrombogenicity index (by −19.5%). Conversely, supplementing NPD increased RBH completeness (by 7.4%) with higher milk atherogenicity index (by 10.5%) and thrombogenicity index (by 8.7%). The adverse effects of NPD on the milk FA profiles can be eliminated when supplemented in combination with FUM. The metagenomic analyses showed that neither FUM nor NPD affect the rumen microbial α- or β-diversity at the strain or gene level. The in vitro study showed that the conversion rate of FUM to propionate was increased from 54.7% to 80.6% when FUM supplemented in combination with biotin and monensin, resulting a higher anti-RBH potential. Accordingly, manipulation of ruminal methanogenesis and propionogenesis can redirect hydrogen toward or away from RBH and thereby influence the milk FA profiles. FUM is a promising feed additive in ruminant not only to reduce the methane emissions as previously proved but also to improve the nutritional desirability of the milk FA profiles for human health.
This study aimed to assess the relationship between COVID-19 infection-related conditions and depressive symptoms among medical staff after easing the zero-COVID policy in China, and to further examine the mediating role of professional burnout.
Methods
A total of 1716 medical staff from all levels of health care institutions in 16 administrative districts of Beijing, China, were recruited to participate at the end of 2022 in this cross-sectional study. Several multiple linear regressions and mediating effects tests were performed to analyze the data.
Results
At the beginning of the end of the zero-COVID policy in China, 91.84% of respondents reported infection with COVID-19. After adjusting for potential confounding variables, the severity of infection symptoms was significantly positively associated with high levels of depressive symptoms (β = 0.06, P < 0.001), and this association was partially mediated by professional burnout. Specifically, emotional exhaustion (95% CI, 0.131, 0.251) and depersonalization (95% CI, 0.009, 0.043) significantly mediated the association between the severity of infection symptoms and depressive symptoms.
Conclusions
The mental health of medical staff with more severe symptoms of COVID-19 infection should be closely monitored. Also, interventions aimed at reducing emotional exhaustion and depersonalization may effectively reduce their risk of developing depressive symptoms.