Traditional Chinese eight brocade exercise (TCEBE) with same cycle and frequency and different durations has an effect on patients with chronic heart failure (CHF). However, relevant reports on the ...topic are lacking.
This study aims to explore the differences of rehabilitation effect by conducting TCEBE with the same cycle and frequency and different single exercise time for patients with CHF.
A total of 103 patients with CHF were randomly divided into long-time group (LTG), short-time group (STG) and control group (CG). The subjects in the three groups were given corresponding routine treatment. In addition, under the guidance of professional TCEBE coaches and nurses, TCEBE was conducted for 12 weeks (3 times/week) for LTG (60 min/time) and STG (30 min/time). Minnesota living with heart failure questionnaire (MLHFQ) was used, and 6-min walk (6MWK) and brain nautical peptide (BNP) were tested.
1) At 12 weeks, the comparison between groups obtained the following results: For the LTG, MLHFQ was less than that of the CG (P < 0.01), 6MWT was greater than that of the CG (P < 0.05), and 6MWT was greater than that of the STG (P < 0.05); for the STG, MLHFQ was less than that of the CG (P < 0.05); no significant difference in BNP was found among the three groups; 2) At 12 weeks and 0 weeks, the comparison obtained the following results: For the LTG, MLHFQ decreased by 37.7 %, and 6MWT increased by 46.7 % (P < 0.01); for the STG, MLHFQ decreased by 31.7 %, and 6MWT increased by 31.5 % (P < 0.01); for the CG, MLHFQ decreased by 14.6 %, and 6MWT increased by 19.7 % (P < 0.05); no significant change in BNP was found in each group.
TCEBE of two kinds of duration improves the quality of life and 6MWT of patients with CHF but has no positive effect on BNP. Compared with 30-min/time, 60-min/time further improves 6MWT in patients with CHF but has no additional benefit on quality of life.
•Physical exercise can improve exercise tolerance, improve the symptoms of patients with CHF and reduce mortality and rehospitalisation rate.•Previous studies have suggested that regular TCEBE has a positive effect on patients with CHF.•Whether the length of a single TCEBE affects the exercise effect is worth exploring.•Compared with 30-min/time exercise, 60-min/time exercise further improved the 6MWT of patients with CHF but did not improve the quality of life.
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•The circular or elliptical arc is used in the struts through the curving lattice strategy, maintaining lightweight, relieving stress concentration.•Theoretical prediction models with ...a high calculation accuracy of elastic modulus ratios are established.•The specific elastic modulus and specific compressive strength of curving lattice structures are maximally raised 213.7% and 126.2% the original.•The curving lattice structure has a superior energy absorption capacity with a maximum increase of 92.9% the original.
A porous lattice structure with highly controllable mechanical properties, low weight, and high strength is the most promising option for many fields, such as the aerospace, automobile, and biomedical industries. However, the most common and critical issue is the excessively high stress concentration at the struts’ nodes when the lattice structure is loaded. Thus, a curving lattice design strategy is proposed, maintaining a light structure, through which either a circular or elliptical arc is used in the lattice struts to obtain new forms of curving lattice structures. By establishing theoretical models and preparing samples by laser powder bed fusion (L-PBF), combined with scanning electron microscopy (SEM), quasi-static uniaxial compressive experiments, finite element analysis (FEA), and Gibson-Ashby models, excellent results were obtained. The stress distribution of the original under the loads was altered in the curving lattice structure and the stress concentration at the nodes of the struts was effectively relieved, dramatically improving its mechanical properties. Compared with the original structure, the specific elastic modulus and specific compressive strength of curving lattice structures were maximally increased by 213.7% and 126.2%, respectively. Meanwhile, the curving lattice structure had a superior energy absorption capacity, with a significant increase of 92.9%.
To assess the association between the risk of malnutrition, as estimated by the Patient-Generated Subjective Global Assessment (PG-SGA) numerical scores, and adverse outcomes in oncology patients.
...Systematic review and meta-analysis.
A comprehensive search was conducted in PubMed, Web of Science, Embase, CKNI, VIP, Sinomed and Wanfang databases. Studies that examined the association between the risk of malnutrition, as estimated by the PG-SGA numerical scores, and overall survival (OS) or postoperative complications in oncology patients were included. Patients were classified as low risk (PG-SGA ≤ 3), medium risk (PG-SGA 4-8) and high risk of malnutrition (PG-SGA > 8).
Nineteen studies reporting on twenty articles (
9286 patients).
The prevalence of medium and high risk of malnutrition ranged from 16·0 % to 71·6 %. A meta-analysis showed that cancer patients with medium and high risk of malnutrition had a poorer OS (adjusted hazard ratios (HR) 1·98; 95 % CI 1·77, 2·21) compared with those with a low risk of malnutrition. Stratified analysis revealed that the pooled HR was 1·55 (95 % CI 1·17, 2·06) for medium risk of malnutrition and 2·65 (95 % CI 1·90, 3·70) for high risk of malnutrition. Additionally, the pooled adjusted OR for postoperative complications was 4·65 (95 % CI 1·61, 13·44) for patients at medium and high risk of malnutrition.
The presence of medium and high risk of malnutrition, as estimated by the PG-SGA numerical scores, is significantly linked to poorer OS and an increased risk of postoperative complications in oncology patients.
The ratio of the two roots of the Langmuir kinetic rate equation at equilibrium is a critical factor for assessing the possibility of reducing the Langmuir kinetics to the pseudo first- (PFO) and ...second-order (PSO) models of batch adsorption. This critical factor solely depends on the ratio of available adsorbate to adsorbent capacity and the product of the Langmuir equilibrium constant and the adsorbent capacity.
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•Derivation of physical meaning of two roots of the Langmuir rate equation.•Derivation of applicability criteria for the pseudo first- and second-order models.•The criteria, the ratio of the two roots, are solely determined by two factors.•Determination of correct pseudo-first- and second-order rate constant.•Detailed analyses on the errors introduced if the criteria are not satisfied.
The pseudo first- (PFO) and second-order (PSO) kinetic models have been extensively applied to study the kinetics of interfacial processes, for example, separation or removal of toxic metal ions from aqueous solution by adsorption. However, the two models were used without any specialization of operating conditions and their theoretical origin is not well understood. The aim of the present study is to provide clear physical understanding on the relationships of the Langmuir kinetics with the two models. The conditions under which the Langmuir kinetics can be reduced to the simplified models and their explicit dependence on operating conditions and isotherm parameters are provided. We adopt the square root method to obtain two roots of the differential Langmuir rate equation at equilibrium, then prove that one root is the surface coverage fraction and the other is the reciprocal of adsorption efficiency at equilibrium, and show that the root ratio is a critical factor in assessing the applicability of the PFO and PSO models. This critical factor solely depends on the ratio of available adsorbate to adsorbent capacity and the product of the Langmuir equilibrium constant and adsorbent capacity. The reduction of the Langmuir kinetics to the PFO and PSO models can be valid only under extreme conditions. The system with too high or too low available adsorbate relative to the maximum adsorbent capacity or with too small adsorption rate constant multiplied by the maximum adsorbent capacity relative to the desorption rate constant might be approximately described by the PFO model. On the other extreme that available adsorbent capacity matches available adsorbate and desorption rate constant is negligible compared with the adsorption rate constant multiply by the maximum adsorbent capacity, the PSO model could replace the Langmuir kinetics. As such, the desorption part in the Langmuir rate equation disappears and the reversible Langmuir kinetics is reduced to irreversible process. Obviously, this is hardly encountered in reality. The present study offers physical insights into the relationships between the Langmuir kinetics with the PFO and PSO models in terms of operating conditions and isotherm parameters.
The development of science and technology (sci-tech) finance is conducive to improving the transformation quality of sci-tech achievements and optimizing the allocation of resources. However, the ...current sci-tech finance field in China is mainly promoted by the way of government work, and the theoretical research on the operation mechanism and system structure of sci-tech finance is relatively lagging. This article constructs the research framework of the sci-tech financial ecosystem from the perspective of ecology, uses the quantitative method of index design to deconstruct the gap between China and other major countries in the world, and analyzes the reasons and enlightenment. It is expected to provide decision-making support for relevant policies from the perspective of top-level design while promoting theoretical research.
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•Graded triply periodic minimal surfaces scaffold with adjustable strut size and graded pore size design method was proposed.•A better deformation process and mechanical properties of ...the graded scaffold were found.•The significant energy absorption capacity was gained compared to uniform scaffold.•The graded scaffolds showed a better cell survival rate with the increase of time.
The advantages of “printing the right material in the right position” and “printing the unique structure for unique function” in additive manufacturing make the design of biomimetic graded scaffold of bone tissue engineering possible. Here, under different porosities, we propose a biomimetic graded TPMS scaffold design with adjustable graded pore size, providing guidance for designing porous bone implants without the characteristics of stress concentration, stress shielding and barrier mass transport. Specifically, the structural characteristics of TPMS can be achieved without stress concentration. By adjusting the porosity, the elastic modulus of Ti6Al4V samples can be adjusted in the range of 1158–4567 MPa, which can match the individual selection of mechanical properties of the biological bone. Since the TPMS scaffold is designed by layer-by-layer splicing, through adjusting the height parameters of the single-layer structure, the selective pore size variation can be realized to further match mass transport of biological bone. Then, the in vitro culture experiments have been conducted and the maximum cell survival rate of the scaffold with an offset constant 0.4 is 85.44%, which can meet the mass transport of bone implants. As such, the proposed graded scaffold design in this paper shows excellent potential for orthopedic implants.
•Combined MD and MC methods was first used to address coal swelling.•Temperature has no effect on the maximum adsorption expressed on a volume basis.•Quantify CH4 absorption for both dry and moist ...coal.•Effect of water on CH4 adsorption and coal swelling mechanism were investigated.•Water is preferably adsorbed on oxygen and nitrogen atoms.
A quantitative understanding of methane (CH4) adsorption on dry and moist coal and the mechanism of coal swelling is vital for successful coal bed methane (CBM) projects. CH4 adsorption isotherms of coal with moisture contents ranging from 0 to 3wt% water, the temperature effect on maximum adsorption capacity, coal swelling, and adsorbed phase density have been modeled by performing combined Monte Carlo (MC) and molecular dynamics (MD) simulations at temperatures of 308 and 370K (35 and 97°C) and at pressures up to 10MPa. Simulation results demonstrate that absolute adsorption (expressed as a mass basis) divided by bulk density is independent of temperature for CH4 on dry coal when pressure is over 8MPa. Both the adsorption capacity and adsorption rate of CH4 decrease, while coal swells as moisture content increases. These results show that the presence of water in the coal matrix reduces the interaction between the coal and methane. Our results indicate that coal–water interaction dominates and is the main contributing factor to the coal swelling. The interaction of CH4–H2O and CH4–CH4 is negligible and the absolute adsorption of CH4 on both dry and moist coal follows the Langmuir isotherm for the pressure range simulated. This study provides a quantitative understanding of the effects of moisture and temperature on CH4 adsorption, coal swelling, and the adsorbed CH4 density from a microscopic perspective. Molecular modeling proves to be a valuable and cost-effective tool for studying gas adsorption behavior in complex and complicated systems.
In order improve the poor mechanical properties of the body-centred cubic (BCC) lattice structure, which suffers from the stress concentration effects at the nodes of the BCC unit cell, a ...graded-strut design method is proposed to increase the radii corner of the BCC nodes, which can obtain a new graded-strut body-centred cubic (GBCC) unit cell. After the relative density equation and the force model of the structure are obtained, the quasi-static uniaxial compression experiments and finite element analysis (FEA) of GBCC samples and BCC samples are performed. The experimental results show that for the fabricated samples with the same relative density, the GBCC can increase the initial stiffness by at least 38.20%, increase the plastic failure strength by at least 34.12%, compared with the BCC. Coupled experimental and numerical results not only suggest that the GBCC has better mechanical and impact resistance properties than the BCC, but also indicate that as the radii corner increases, the stress concentration effect at the node and the mechanical properties will be improved, which validates the proposed design method for graded-strut unit cells and can provide guidance for the design and future research on ultra-light lattice structures in related fields.
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•The bidirectionally graded strategy is proposed to realize the compliant connection and promote the improvement of mechanical properties.•The dependence of the structure's mechanical ...performance on the gradient direction and the degree of gradient variation are obtained.•A method for predicting the stiffness of bidirectionally graded structures is proposed to effectively predict the stiffness of graded body-centered cubic lattice structures.
Functionally graded lattice structures are gaining increasing attention due to their potential to enable the customization of the structural response and development of multi-functional applications. However, some grading methods may lead to weak layers or discontinuous unit cells. These problems can be overcome by varying the morphology, but the mechanical performance is only slightly improved, limiting the application of lattice structures. This work proposes a bidirectionally graded lattice structure, wherein the gradient design is simultaneously implemented in parallel and perpendicularly to the load direction. Experimental samples fabricated through laser powder bed fusion (L-PBF) and using PA2200 as the matrix material, were subjected to quasi-static compression tests. The results showed that the bidirectionally graded lattice structure attains a significantly higher compressive modulus, yield stress, and plateau stress (59.8%, 43.0%, and 33.9% higher, respectively) compared with a unidirectionally graded lattice structure. Moreover, a proposed stiffness prediction method was appropriate for effectively estimating the modulus of graded body-centered cubic lattice structures, which combined with the understanding of the influence of gradient parameters, allows the realization of a tailored structural performance. In conclusion, the proposed bidirectionally graded strategy and experimental findings provide an effective reference for the design of multi-functional lightweight additive manufactured parts.
This study examined the impact of parental involvement on the psychological adjustment of children with autism spectrum disorder (ASD), and the role of parenting self-efficacy and parenting stress in ...the transition from kindergarten to primary school.
Using the questionnaires, we collected data from 237 Chinese parents of children with ASD.
Mediation analyses showed that parental involvement partially promoted the psychological adjustment of children with ASD, which was reflected in the fact that parental involvement promoted children's prosocial behavior but did not reduce their emotional/behavioral problems. Mediation analyses also revealed the role of the mediator in parenting stress between parental involvement and the psychological adjustment of children. Additionally, the results suggested that parenting self-efficacy and parenting stress played a chain-mediating role in the association between parental involvement and psychological adjustment in children with ASD.
These findings enhance our understanding of the mechanisms underlying the relationship between parental involvement and psychological adjustment in children with ASD in the transition from kindergarten to primary school.
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