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To explore the associations between nutrition literacy (NL) and possible sarcopenia in older Chinese adults. A cross-sectional study was conducted. NL was assessed using a twelve-item short-form NL scale. Possible sarcopenia was identified using SARC-CALF. Logistic regression was used to calculate OR and 95 % CI for NL and the incidence of possible sarcopenia. A total of 1338 older individuals, aged 71·41 (sd 6·84) years, were enrolled in this study. After confounders were adjusted for, older adults in the upper quartile of NL were found to be 52 % less likely to have possible sarcopenia than those in the lower quartile of NL (OR = 0·48, 95 % CI: 0·29, 0·77). The associations between NL and possible sarcopenia were present only in those who lived in rural areas (OR: 0·38, 95 % CI: 0·19, 0·77), had a primary school education or less (OR: 0·21, 95 % CI: 0·09, 0·48), had a monthly income < 3000 RMB (OR: 0·39, 95 % CI: 0·22, 0·70) and had chronic diseases (OR: 0·37, 95 % CI: 0·22, 0·63). Moreover, an interaction effect was observed between having a chronic disease and junior high school education and being in the upper quartile of NL. The prevalence of possible sarcopenia in older Chinese adults is substantial, with prevalence decreasing with increasing NL. Moreover, the association between NL and possible sarcopenia varies by residence type, education level, monthly income and chronic disease experience. Targeted NL interventions are required to prevent and manage sarcopenia in older adults, particularly those with low socio-economic status and chronic diseases.
Depression is highly prevalent in haemodialysis patients, and diet might play an important role. Therefore, we conducted this cross-sectional study to determine the association between dietary fatty acids (FA) consumption and the prevalence of depression in maintenance haemodialysis (MHD) patients. Dietary intake was assessed using a validated FFQ between December 2021 and January 2022. The daily intake of dietary FA was categorised into three groups, and the lowest tertile was used as the reference category. Depression was assessed using the Patient Health Questionnaire-9. Logistic regression and restricted cubic spline (RCS) models were applied to assess the relationship between dietary FA intake and the prevalence of depression. As a result, after adjustment for potential confounders, a higher intake of total FA [odds ratio (OR)T3 vs. T1 = 1·59, 95 % confidence interval (CI) = 1·04, 2·46] and saturated fatty acids (SFA) (ORT3 vs. T1 = 1·83, 95 % CI = 1·19, 2·84) was associated with a higher prevalence of depressive symptoms. Significant positive linear trends were also observed (P < 0·05) except for SFA intake. Similarly, the prevalence of depression in MHD patients increased by 20% (OR = 1.20, 95% CI = 1.01–1.43) for each standard deviation increment in SFA intake. RCS analysis indicated an inverse U-shaped correlation between SFA and depression (Pnonlinear > 0·05). Additionally, the sensitivity analysis produced similar results. Furthermore, no statistically significant association was observed in the subgroup analysis with significant interaction. In conclusion, higher total dietary FA and SFA were positively associated with depressive symptoms among MHD patients. These findings inform future research exploring potential mechanism underlying the association between dietary FA and depressive symptoms in MHD patients.
This study presents a dual-channel vortex generator (VG) that leverages the snap-through behaviour of flexible sheets. The VG outperforms a similar-sized rigid VG in generating vortices within dual-channel flows while minimizing pressure loss. Numerical simulations using the immersed boundary-lattice Boltzmann method analyse the dynamics and vortex generation performance of the sheet under various system parameters. Two distinct modes are identified for the elastic sheet: a sustained snap-through mode (SSTM) and a dormant mode (DM). The sheet's mode is predominantly influenced by its length ratio (L*), bending stiffness $(K_b^\ast )$ and flow strength, with the mass ratio having a minimal impact. The sheet exhibiting regular SSTM can effectively generate vortices in both channels and the vortex generation performance can be conveniently tuned by altering the sheet's initial buckling (i.e. L*). An increase in $K_b^\ast $ results in a higher critical Reynolds number (Rec) required for mode transition. An increase in L*, however, initially raises Rec and then lowers it, suggesting an optimal length ratio (approximately 0.7 for our considered system) for minimizing the Rec necessary to trigger SSTM. Furthermore, a disparity in the flow strength between channels is found to suppress the snap-through of the sheet; a greater disparity, however, is permissible to induce the SSTM of more compliant sheets. These findings underscore the potential of snap-through behaviour for enhanced flow manipulation in dual-channel systems.
The Righi–Leduc heat flux generated by the self-generated magnetic field in the ablative Rayleigh–Taylor instability driven by a laser irradiating thin targets is studied through two-dimensional extended-magnetohydrodynamic simulations. The perturbation structure gets into a low magnetization state though the peak strength of the self-generated magnetic field could reach hundreds of teslas. The Righi–Leduc effect plays an essential impact both in the linear and nonlinear stages, and it deflects the total heat flux towards the spike base. Compared to the case without the self-generated magnetic field included, less heat flux is concentrated at the spike tip, finally mitigating the ablative stabilization and leading to an increase in the velocity of the spike tip. It is shown that the linear growth rate is increased by about 10% and the amplitude during the nonlinear stage is increased by even more than 10% due to the feedback of the magnetic field, respectively. Our results reveal the importance of Righi–Leduc heat flux to the growth of the instability and promote deep understanding of the instability evolution together with the self-generated magnetic field, especially during the acceleration stage in inertial confinement fusion.
This paper investigates the issue of tracking control for a free-floating space manipulator with prescribed performance constraints, considering the inertia uncertainties, internal disturbances and input saturation. An inherently continuous adaptive controller is proposed by incorporating non-singular fixed-time sliding mode control, prescribed performance control (PPC), and auxiliary compensation. First, a modified non-singular fast fixed-time terminal sliding surface is constructed, which has a shorten convergence time than the conventional fixed-time sliding surface. Unlike the existing complicated PPCs, a simple structure controller is developed to satisfy prescribed performance constraints through a unique tangent-type PPC technique. The input saturation is then compensated adaptively by an auxiliary mechanism. The Lyapunov theory thoroughly validates the stability and fixed-time convergence of the closed-loop tracking system. With the suggested control scheme, the system states can converge quickly to a small neighbourhood around the origin within a preassigned time, while the position tracking error can be confined within a prescribed performance bounds even in the presence of input saturation. Compared to the existing tracking methods, the suggested control approach has the advantages of faster transient convergence, higher steady-state tracking precision, and stronger robustness. Simulation comparisons demonstrate the effectiveness and superiority of the proposed controller.
Customer preference modelling has been widely used to aid engineering design decisions on the selection and configuration of design attributes. Recently, network analysis approaches, such as the exponential random graph model (ERGM), have been increasingly used in this field. While the ERGM-based approach has the new capability of modelling the effects of interactions and interdependencies (e.g., social relationships among customers) on customers’ decisions via network structures (e.g., using triangles to model peer influence), existing research can only model customers’ consideration decisions, and it cannot predict individual customer’s choices, as what the traditional utility-based discrete choice models (DCMs) do. However, the ability to make choice predictions is essential to predicting market demand, which forms the basis of decision-based design (DBD). This paper fills this gap by developing a novel ERGM-based approach for choice prediction. This is the first time that a network-based model can explicitly compute the probability of an alternative being chosen from a choice set. Using a large-scale customer-revealed choice database, this research studies the customer preferences estimated from the ERGM-based choice models with and without network structures and evaluates their predictive performance of market demand, benchmarking the multinomial logit (MNL) model, a traditional DCM. The results show that the proposed ERGM-based choice modelling achieves higher accuracy in predicting both individual choice behaviours and market share ranking than the MNL model, which is mathematically equivalent to ERGM when no network structures are included. The insights obtained from this study further extend the DBD framework by allowing explicit modelling of interactions among entities (i.e., customers and products) using network representations.
The phase summation effect in sum-frequency mixing process is utilized to avoid a nonlinearity obstacle in the power scaling of single-frequency visible or ultraviolet lasers. Two single-frequency fundamental lasers are spectrally broadened by phase modulation to suppress stimulated Brillouin scattering in fiber amplifier and achieve higher power. After sum-frequency mixing in a nonlinear optical crystal, the upconverted laser returns to single frequency due to phase summation, when the phase modulations on two fundamental lasers have a similar amplitude but opposite sign. The method was experimentally proved in a Raman fiber amplifier-based laser system, which generated a power-scalable sideband-free single-frequency 590 nm laser. The proposal manifests the importance of phase operation in wave-mixing processes for precision laser technology.
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.
The purpose of this study was to analyse the clinical characteristics of patients with severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) PCR re-positivity after recovering from coronavirus disease 2019 (COVID-19). Patients (n = 1391) from Guangzhou, China, who had recovered from COVID-19 were recruited between 7 September 2021 and 11 March 2022. Data on epidemiology, symptoms, laboratory test results and treatment were analysed. In this study, 42.7% of recovered patients had re-positive result. Most re-positive patients were asymptomatic, did not have severe comorbidities, and were not contagious. The re-positivity rate was 39%, 46%, 11% and 25% in patients who had received inactivated, mRNA, adenovirus vector and recombinant subunit vaccines, respectively. Seven independent risk factors for testing re-positive were identified, and a predictive model was constructed using these variables. The predictors of re-positivity were COVID-19 vaccination status, previous SARs-CoV-12 infection prior to the most recent episode, renal function, SARS-CoV-2 IgG and IgM antibody levels and white blood cell count. The predictive model could benefit the control of the spread of COVID-19.
High-power continuous-wave single-frequency Er-doped fiber amplifiers at 1560 nm by in-band and core pumping of a 1480 nm Raman fiber laser are investigated in detail. Both co- and counter-pumping configurations are studied experimentally. Up to 59.1 W output and 90% efficiency were obtained in the fundamental mode and linear polarization in the co-pumped case, while less power and efficiency were achieved in the counter-pumped setup for additional loss. The amplifier performs indistinguishably in terms of laser linewidth and relative intensity noise in the frequency range up to 10 MHz for both configurations. However, the spectral pedestal is raised in co-pumping, caused by cross-phase modulation between the pump and signal laser, which is observed and analyzed for the first time. Nevertheless, the spectral pedestal is 34.9 dB below the peak, which has a negligible effect for most applications.
We report VLBI monitoring observations of the 22 GHz H2O masers toward the Mira variable BX Cam. Data from 37 epochs spanning ∼3 stellar pulsation periods were obtained between May 2018 and June 2021 with a time interval of 3–4 weeks. In particular, the VERA dual-beam system was used to measure the kinematics and parallaxes of the H2O maser features. The obtained parallax, 1.79±0.08 mas, is consistent with Gaia EDR3 and previous VLBI measurements. The position of the central star was estimated relied on Gaia EDR3 data and the center position of the 43 GHz SiO maser ring imaged with KVN. Analysis of the 3D maser kinematics revealed an expanding circumstellar envelope with a velocity of 13±4 km s−1 and significant spatial and velocity asymmetries. The H2O maser animation achieved by our dense monitoring program manifests the propagation of shock waves in the circumstellar envelope of BX Cam.
A method is presented for configuration selection to obtain the best tip-over stability of a modular reconfigurable mobile manipulator (MRMM) under various application situations. The said MRMM consists of a modular reconfigurable robot (MRR) mounted on a mobile platform. The MRR in different configurations creates different wrenches onto the mobile platform, leading to different tip-over moments of the MRMM, even though the joint speeds or tip speeds remain the same. The underlying problem pertains to selecting one configuration of MRR for reconfiguration that would obtain the best tip-over stability under a given application. First, all the permissible configurations are identified through an enumeration method. Then, the feasible configurations are determined based on application-oriented workspace classifications. At last, two workspace indices, vertical reach and horizontal reach, are used to select an optimal configuration. The tip-over stability analysis and evaluation of MRMM are carried out for verification for three cases including vertical, horizontal, and general 3D space applications. The results demonstrate the effectiveness of the proposed method.
This work studies the detachment of a micron-sized spherical particle from a surface with concave roughness in a linear shear flow. The concave roughness is described as regularly spaced hollow hemispheres below a flat surface and is characterised by two dimensionless parameters, i.e. dimensionless asperity distance and asperity size ratio. The hydrodynamic force and torque on the particle are calculated by performing lattice Boltzmann simulations for particle Reynolds numbers ranging from 0.02 to 40. Empirical correlations of the drag, lift and torque coefficients of the particle as functions of the particle Reynolds number and the asperity size ratio are proposed. For detachment by lifting, sliding and rolling, a numerical approach to calculate the critical particle Reynolds number (i.e. above which the particle can detach from the surface) is proposed. It is found that the dimensionless asperity distance and the distribution of asperities on the rough surface have a minor influence on the hydrodynamic force and torque on the particle, and the detachment of the particle becomes more difficult as the particle sits deeper in a larger hole. Both the empirical correlations and the numerical approach can be implemented into Lagrangian particle tracking and can accurately predict the detachment of particles from the surface with concave roughness or the detachment of particles embedded in a flat surface.
Previous analyses of grey and white matter volumes have reported that schizophrenia is associated with structural changes. Deep learning is a data-driven approach that can capture highly compact hierarchical non-linear relationships among high-dimensional features, and therefore can facilitate the development of clinical tools for making a more accurate and earlier diagnosis of schizophrenia.
Aims
To identify consistent grey matter abnormalities in patients with schizophrenia, 662 people with schizophrenia and 613 healthy controls were recruited from eight centres across China, and the data from these independent sites were used to validate deep-learning classifiers.
Method
We used a prospective image-based meta-analysis of whole-brain voxel-based morphometry. We also automatically differentiated patients with schizophrenia from healthy controls using combined grey matter, white matter and cerebrospinal fluid volumetric features, incorporated a deep neural network approach on an individual basis, and tested the generalisability of the classification models using independent validation sites.
Results
We found that statistically reliable schizophrenia-related grey matter abnormalities primarily occurred in regions that included the superior temporal gyrus extending to the temporal pole, insular cortex, orbital and middle frontal cortices, middle cingulum and thalamus. Evaluated using leave-one-site-out cross-validation, the performance of the classification of schizophrenia achieved by our findings from eight independent research sites were: accuracy, 77.19–85.74%; sensitivity, 75.31–89.29% and area under the receiver operating characteristic curve, 0.797–0.909.
Conclusions
These results suggest that, by using deep-learning techniques, multidimensional neuroanatomical changes in schizophrenia are capable of robustly discriminating patients with schizophrenia from healthy controls, findings which could facilitate clinical diagnosis and treatment in schizophrenia.
Neuroimaging- and machine-learning-based brain-age prediction of schizophrenia is well established. However, the diagnostic significance and the effect of early medication on first-episode schizophrenia remains unclear.
Aims
To explore whether predicted brain age can be used as a biomarker for schizophrenia diagnosis, and the relationship between clinical characteristics and brain-predicted age difference (PAD), and the effects of early medication on predicted brain age.
Method
The predicted model was built on 523 diffusion tensor imaging magnetic resonance imaging scans from healthy controls. First, the brain-PAD of 60 patients with first-episode schizophrenia, 60 healthy controls and 21 follow-up patients from the principal data-set and 40 pairs of individuals in the replication data-set were calculated. Next, the brain-PAD between groups were compared and the correlations between brain-PAD and clinical measurements were analysed.
Results
The patients showed a significant increase in brain-PAD compared with healthy controls. After early medication, the brain-PAD of patients decreased significantly compared with baseline (P < 0.001). The fractional anisotropy value of 31/33 white matter tract features, which related to the brain-PAD scores, had significantly statistical differences before and after measurements (P < 0.05, false discovery rate corrected). Correlation analysis showed that the age gap was negatively associated with the positive score on the Positive and Negative Syndrome Scale in the principal data-set (r = −0.326, P = 0.014).
Conclusions
The brain age of patients with first-episode schizophrenia may be older than their chronological age. Early medication holds promise for improving the patient's brain ageing. Neuroimaging-based brain-age prediction can provide novel insights into the understanding of schizophrenia.
Residual negative symptoms and cognitive impairment are common for chronic schizophrenia patients. The aim of this study was to investigate the efficacy of a mindfulness-based intervention (MBI) on negative and cognitive symptoms of schizophrenia patients with residual negative symptoms.
Methods
In this 6-week, randomized, single-blind, controlled study, a total of 100 schizophrenia patients with residual negative symptoms were randomly assigned to the MBI or control group. The 6-week MBI group and the control group with general rehabilitation programs maintained their original antipsychotic treatments. The scores for the Positive and Negative Syndrome Scale (PANSS), the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), and the Symptom Checklist 90 (SCL-90) were recorded at baseline and week 6 to assess psychotic symptoms, cognitive performance, and emotional state, respectively.
Results
Compared with general rehabilitation programs, MBI alleviated the PANSS-negative subscore, general psychopathology subscore, and PANSS total score in schizophrenia patients with residual negative symptoms (F = 33.77, pBonferroni < 0.001; F = 42.01, pBonferroni < 0.001; F = 52.41, pBonferroni < 0.001, respectively). Furthermore, MBI improved RBANS total score and immediate memory subscore (F = 8.80, pBonferroni = 0.024; F = 11.37, pBonferroni = 0.006), as well as SCL-90 total score in schizophrenia patients with residual negative symptoms (F = 18.39, pBonferroni < 0.001).
Conclusions
Our results demonstrate that MBI helps schizophrenia patients with residual negative symptoms improve clinical symptoms including negative symptom, general psychopathology symptom, and cognitive impairment.
Patients with schizophrenia and individuals with schizotypy, a subclinical group at risk for schizophrenia, have been found to have impairments in cognitive control. The Dual Mechanisms of Cognitive Control (DMC) framework hypothesises that cognitive control can be divided into proactive and reactive control. However, it is unclear whether individuals with schizotypy have differential behavioural impairments and neural correlates underlying these two types of cognitive control.
Method:
Twenty-five individuals with schizotypy and 26 matched healthy controls (HCs) completed both reactive and proactive control tasks with electroencephalographic data recorded. The proportion of congruent and incongruent trials was manipulated in a classic colour-word Stroop task to induce proactive or reactive control. Proactive control was induced in a context with mostly incongruent (MI) trials and reactive control in a context with mostly congruent (MC) trials. Two event-related potential (ERP) components, medial frontal negativity (MFN, associated with conflict detection) and conflict sustained potential (conflict SP, associated with conflict resolution) were examined.
Results:
There was no significant difference between the two groups in terms of behavioural results. In terms of ERP results, in the MC context, HC exhibited significantly larger MFN (360–530 ms) and conflict SP (600–1000 ms) amplitudes than individuals with schizotypy. The two groups did not show any significant difference in MFN or conflict SP in the MI context.
Conclusions:
The present findings provide initial evidence for dissociation of neural activation between proactive and reactive cognitive control in individuals with schizotypy. These findings help us understand cognitive control deficits in the schizophrenia spectrum.
The development of thermoelectric measurement technology at nanoscale is a challenging task. Here, a novel MEMS-based dual temperature control (DTC) measurement method for thermoelectric properties of individual nanowires was proposed. Different from conventional thermal bridge testing devices, this DTC thermoelectric testing device can obtain the thermoelectric properties by independently control ambient temperature and temperature difference between two ends of the nanowires through two separate resistance thermometers without auxiliary heating devices. The reliability of the model and the testing accuracy were verified by accurately measuring the thermal conductivity, electrical conductivity, and the absolute value of the Seebeck coefficient of VO2 nanowires.
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.