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1.
Environ Sci Technol ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967661

RESUMO

Although exogenous chemicals frequently exhibit a biphasic response in regulating plant growth, characterized by low-dose stimulation and high-dose inhibition, the underlying mechanisms remain elusive. This study demonstrates, for the first time, the compensatory function of rhizosphere microbiota in assisting plants to withstand pesticide stress. It was observed that pak choi plants, in response to foliar-spraying imidacloprid at both low and high doses, could increase the total number of rhizosphere bacteria and enrich numerous beneficial bacteria. These bacteria have capabilities for promoting plant growth and degrading the pesticide, such as Nocardioides, Brevundimonas, and Sphingomonas. The beneficial bacterial communities were recruited by stressed plants through increasing the release of primary metabolites in root exudates, such as amino acids, fatty acids, and lysophosphatidylcholines. At low doses of pesticide application, the microbial compensatory effect overcame pesticide stress, leading to plant growth promotion. However, with high doses of pesticide application, the microbial compensatory effect was insufficient to counteract pesticide stress, resulting in plant growth inhibition. These findings pave the way for designing improved pesticide application strategies and contribute to a better understanding of how rhizosphere microbiota can be used as an eco-friendly approach to mitigate chemical-induced stress in crops.

2.
BMC Nurs ; 22(1): 388, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37853383

RESUMO

BACKGROUND: Burnout is a major concern in healthcare professions. Although theory and empirical evidence support the relationship between job stressors and burnout, the question remains how and when the job stressors are related to burnout. Based on conservation of resources theory and effort recovery model, the current study aimed to provide a deeper understanding of the effect of job stressors on burnout by investigating the mediating role of need for recovery and the moderating role of career calling. METHODS: A cross-sectional online survey was conducted among 709 nurses enrolled from eight public hospitals in China. The Work Stressors Scale, Psychological Detachment Scale, Brief Calling Scale, and Maslach Burnout Inventory were used to collect data. Hierarchical regression analysis with bootstrapping procedure was performed to test the proposed model. RESULTS: The results showed that need for recovery mediated the job stressors-burnout relationship, and that high career calling buffered against the relationships between job stressors and need for recovery and burnout. Furthermore, the result revealed a moderated mediation model that career calling buffered the indirect effect of job stressors on burnout through need for recovery. CONCLUSIONS: Our findings suggest that environmental demands and personal resource are important antecedents of nurses' burnout. Career calling as personal resources can serve as a protective factor that guards against burnout. Thus, nursing managers can reduce nurse burnout by focusing on effective strategies related to recovery experiences, as well as investing in training career calling.

3.
Adv Colloid Interface Sci ; 305: 102684, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35525088

RESUMO

Droplet dynamics and condensation phenomena are widespread in nature and industrial applications, and the fundamentals of various technological applications. Currently, with the rapid development of interfacial materials, microfluidics, micro/nano fabrication technology, as well as the intersection of fluid mechanics, interfacial mechanics, heat and mass transfer, thermodynamics and reaction kinetics and other disciplines, the preparation and design of various novel functional surfaces have contributed to the local modulation of droplets (including nucleation, jumping and directional migration) and the improvement of condensation heat transfer, further deepening the understanding of relevant mechanisms. The wetting and dynamic characteristics of droplets involve complex solid-liquid interfacial interactions, so that the local modulation of microdroplets and the extension of enhanced condensation heat transfer by means of complex micro/nano structures and hydrophilic/hydrophobic properties is one of the current hot topics in heat and mass transfer research. This work presents a detailed review of several scientific issues related to the droplet dynamics and dropwise condensation heat transfer under the influence of multiple factors (including fluid property, surface structure, wettability, temperature external field, etc.). Firstly, the basic theory of droplet wetting on the solid wall is introduced, and the mechanism of solid-liquid interfacial interaction involving droplet jumping and directional migration on the functional surfaces under the various influencing factors is discussed. Optimizing the surface structure for the local modulation of droplets is of guidance for condensation heat transfer. Secondly, we summarize the existing theoretical models of dropwise condensation applicable to various functional surfaces and briefly outline the current numerical models for simulating dropwise condensation at different scales, as well as the fabricating techniques of coatings and functional surfaces for enhancing heat transfer. Finally, the relevant problems and challenges are summarized and future research is discussed.

4.
Sci Total Environ ; 834: 155354, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35460773

RESUMO

Deoxynivalenol (DON) and fumonisin B1 (FB1), as a group of highly toxic secondary metabolites, have become a potential source of water environmental pollutants. To minimize two mycotoxins exposure to consumers, a dual lateral flow immunoassay (LFIA) integrated with the smartphone was reported for simultaneous and quantitative detection of DON and FB1 in the water environment. The significantly improved sensitivity was contributed to a smartphone-based device with the ability to image and analyze results. Under optimized conditions, the detection limits of DON and FB1 were calculated to be 3.46 and 2.65 ng/mL, which were approximately 25 and 10 folds lower than those of the visual detection of the LFIA. This method showed good specificity and a good dynamic linear detection for DON and FB1. The recoveries of DON and FB1 were evaluated by the spiked lake water, river water, and pond water, ranging from 92.47% to 106.2% with the relative standard deviation under 9.13%. Moreover, the results of the developed LFIA showed a high correlation with enzyme-linked immunosorbent assay (ELISA) results, with a correlation coefficient of 0.999 for DON and 0.996 for FB1, respectively. To sum up, the developed LFIA provides a promising platform for sensitive, simultaneous, quantitative, and on-site detection of DON and FB1 in the water environment.


Assuntos
Fumonisinas , Micotoxinas , Fumonisinas/análise , Fumonisinas/toxicidade , Imunoensaio , Micotoxinas/análise , Smartphone , Tricotecenos , Água
5.
Chemosphere ; 299: 134446, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35358551

RESUMO

Soil amendment with biochar may trigger a series of positive and negative biological effects, partly because it interferes quorum sensing (QS) signals synthesized by microorganisms for communication. However, the mechanisms through which biochar interacts with these QS signals remain elusive. This study explored the mechanisms of interactions between N-acyl homoserine lactones (AHLs) and two maize straw-derived biochars (MBs) with different pyrolysis temperature. Pseudo-second-order equation model best depicted AHLs sorption kinetics on MBs. The intra-particle diffusion model revealed that AHLs sorption onto MBs consists of several stages. The sorption isotherms data of AHLs on MBs were in well agreement with both Langmuir and Freundlich models, indicating the occurrence of energetic distribution of active sites on the heterogeneous biochar with multilayer sorption. However, the AHLs sorption capacity on MBs varied, with biochar pyrolyzed at 600 °C displaying a higher AHLs sorption capacity compared with biochar pyrolyzed at 300 °C. It may be attributed to a variety of physiochemical interactions such as pore filling, functional groups complexation, hydrogen bond, and hydrophobic action. The adsorption/partitioning model results and thermodynamic parameters of Gibbs free energy (ΔG) confirmed that physical and chemical sorption occurred concurrently throughout the whole AHLs sorption process, with physical partitioning playing a greater role than surface sorption. The findings suggest that soil amendment with biochar may have a variety of effects on intra/inter-cellular communication, further implying biochar can be specially prepared to mediate soil processes related to microbial communication, like pollutant biodegradation, and carbon/nitrogen cycling.


Assuntos
Acil-Butirolactonas , Zea mays , Adsorção , Carvão Vegetal/química , Cinética , Solo/química
6.
J Healthc Eng ; 2022: 1939844, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35126907

RESUMO

Assessment is critical during the procedure of stroke rehabilitation. However, traditional assessment methods are time-consuming, laborious, and dependent on the skillfulness of the therapist. Moreover, they cannot distinguish whether the improvement comes from the abnormal compensation or the improvement of upper extremity motor function. To make up for the shortcomings of the traditional methods, this study proposes a novel assessment system, which consisted of a rehabilitation robot and motion capture (MoCAP) system. A 9-degree-of-freedom (DOF) kinematic model is established, which consists of the shoulder girdle, shoulder, elbow, and wrist joints. And seven assessment indices are selected for this assessment system, including a range of motion (ROM), shoulder girdle compensation (SGC), trunk compensation (TC), aiming angle (AA), motion error (ME), motion length ratio (MLR), and useful force (UF). For AA, ME, and MLR, all describe the motor ability of the upper extremity, and a linear model was proposed to map these three indices into one index, called motor control ability (MCA). Then, this system can quantitatively evaluate human upper extremity motor function from joint space kinematics, Cartesian space kinematics, and dynamics. Three healthy participants were invited to verify the effectiveness of this system. The preliminary results show that all participants' handedness performs a little better than the nonhandedness. And the performance of the participants and the change of all the upper limb joints can be directly watched from the trajectory of the hand and joint angles' curve. Therefore, this assessment system can evaluate the human upper limb motor function well. Future studies are planned to recruit elderly volunteers or stroke patients to further verify the effectiveness of this system.


Assuntos
Robótica , Reabilitação do Acidente Vascular Cerebral , Idoso , Fenômenos Biomecânicos , Humanos , Movimento , Robótica/métodos , Reabilitação do Acidente Vascular Cerebral/métodos , Extremidade Superior
7.
Technol Health Care ; 30(1): 105-116, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34024793

RESUMO

BACKGROUND: With the population aging, post-stroke patients suffering from hemiplegia are also rapidly increasing. It is essential to provide valid rehabilitation methods for hemiplegia patients. Mirror therapy is an effective rehabilitation method and is widely applied in many rehabilitation robots. OBJECTIVE: The aim of this paper is to present a path planning method to guarantee the robot's motion performance during mirror therapy. METHODS: The kinematic framework of the proposed rehabilitation system is detailed, then the reference motion path of the manipulator is calculated according to kinematic transformation. The concept of manipulability is introduced to describe the motion performance of the manipulator. Based on the above work, a path planning method based on A* algorithm is proposed to quantitatively analyze and optimize the motion performance of the manipulator. RESULTS: Preliminary experiments with the proposed rehabilitation system are conducted to verify the proposed path planning method. The characteristics of the proposed method are analyzed through two typical situations. The results showed that the proposed method can build a new path for manipulator, which can ensure the robot's motion performance and is highly consistent with the reference path. CONCLUSION: The results showed that the manipulator could achieve the task with acceptable error, which indicates the potential of the proposed path planning method for mirror therapy.


Assuntos
Robótica , Algoritmos , Fenômenos Biomecânicos , Humanos , Terapia de Espelho de Movimento , Movimento (Física)
8.
Psychol Res Behav Manag ; 14: 1675-1689, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34675707

RESUMO

PURPOSE: Given that extensive studies have documented the wide-ranging benefits of living a calling, determining whether and how living a calling can be improved is of great importance. Although recent research implies that a growth mindset about work may link to self-regulatory processes and living a calling, little research to date has directly examined the relationships between these variables. Building on Burnette's SOMA model, this study was designed to examine the premise that a growth mindset about work was a predictor of living a calling and to explore the mediating role of self-regulation in the growth mindset about work-living a calling link. METHODS: This cross-sectional study was conducted among educational professionals in China. Data were collected from 608 primary and secondary school teachers on growth mindsets about work, self-regulation and living a calling. A structural equation model was used to test the hypothesis that self-regulation would mediate the relationship between a growth mindset about work and living a calling. RESULTS: Consistent with our premise, a growth mindset about work was positively associated with living a calling. Also, a growth mindset about work was significantly associated with self-regulation strategies in terms of goal setting, perseverance, decision making, and learning from mistakes. As hypothesized, a growth mindset about work was related to higher levels of living a calling via goal setting, perseverance, and learning from mistakes. CONCLUSION: The findings contribute to the increasing breadth of the growth mindset literature across various contexts and its consequences for one's living a calling, which expand the nomological web of correlates of growth mindset about work. Furthermore, these findings suggest that fostering a growth mindset about work may facilitate adaptive behaviors and, thereby, serve as a calling intervention.

9.
Technol Health Care ; 29(5): 1029-1045, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33427698

RESUMO

BACKGROUND: The definition of rehabilitation training trajectory is of great significance during rehabilitation training, and the dexterity of human-robot interaction motion provides a basis for selecting the trajectory of interaction motion. OBJECTIVE: Aimed at the kinematic dexterity of human-robot interaction, a velocity manipulability ellipsoid intersection volume (VMEIV) index is proposed for analysis, and the dexterity distribution cloud map is obtained with the human-robot cooperation space. METHOD: Firstly, the motion constraint equation of human-robot interaction is established, and the Jacobian matrix is obtained based on the speed of connecting rod. Then, the Monte Carlo method and the cell body segmentation method are used to obtain the collaborative space of human-robot interaction, and the VMEIV of human-robot interaction is solved in the cooperation space. Finally, taking the upper limb rehabilitation robot as the research object, the dexterity analysis of human-robot interaction is carried out by using the index of the approximate volume of the VMEIV. RESULTS: The results of the simulation and experiment have a certain consistency, which indicates that the VMEIV index is effective as an index of human-robot interaction kinematic dexterity. CONCLUSIONS: The VMEIV index can measure the kinematic dexterity of human-robot interaction, and provide a reference for the training trajectory selection of rehabilitation robot.


Assuntos
Robótica , Reabilitação do Acidente Vascular Cerebral , Fenômenos Biomecânicos , Humanos , Movimento (Física) , Extremidade Superior
10.
J Sci Food Agric ; 101(11): 4473-4480, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33432579

RESUMO

BACKGROUND: The greatest hurdle to commercial marketing of fresh-cut fruits and vegetables is limited shelf life due to microbial hazards and quality deterioration. Atmospheric cold plasma (ACP) is an emerging non-thermal technology with significant potential to improve the safety and storability of fresh products. The objective of this study was to evaluate the effects of ACP, generated in sealed packaging, on the qualitative, metabolic and microbial stability of fresh-cut pears during simulated cold storage. RESULTS: ACP treatments were effective in inhibiting the growth of mesophilic aerobic bacteria, yeast and mold, particularly CP3 (65 kV, 1 min), which could prolong shelf life to the greatest extent. While decontamination was not always associated with an increase in plasma intensity. Moreover, at 65 kV for 1 min, ACP treatment had the potential to retard respiration, and maintain organoleptic properties and other quality attributes. Additionally, peroxidase and pectin methylesterase (PME) activities were reduced immediately after treatments. These effects were dependent on treatment voltage and time, while a subsequent recovery in activity was only observed for PME. CONCLUSION: The results obtained from this study will contribute to an understanding of the effects of in-package ACP treatments on the storability and microbial safety of fresh-cut pears. This knowledge could be beneficial in reducing quality losses for fresh-cut pears and the preservation of other products. © 2021 Society of Chemical Industry.


Assuntos
Conservação de Alimentos/métodos , Frutas/química , Gases em Plasma/farmacologia , Pyrus/metabolismo , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Hidrolases de Éster Carboxílico/metabolismo , Embalagem de Alimentos , Conservação de Alimentos/instrumentação , Frutas/metabolismo , Frutas/microbiologia , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Peroxidase/metabolismo , Proteínas de Plantas/metabolismo , Pyrus/química , Pyrus/microbiologia , Controle de Qualidade
11.
Plants (Basel) ; 9(12)2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33261053

RESUMO

Vacuolar H+-ATPases (V-ATPase) are multi-subunit complexes that function as ATP hydrolysis-driven proton pumps. They play pivotal roles in physiological processes, such as development, metabolism, stress, and growth. However, there have been very few studies on the characterisation of V-ATPase (VHA) genes in Rosaceae species. Therefore, in the present study, we performed a genome-wide analysis and identified VHA gene family members in five Rosaceae species (Pyrus bretschneideri, Malus domestica, Prunus persica, Fragaria vesca, and Prunus mume). A total of 159 VHA genes were identified, and were classified into 13 subfamilies according to the phylogenetic analysis. The structure of VHA proteins revealed high similarity among different VHA genes within the same subgroup. Gene duplication event analysis revealed that whole-genome duplications represented the major pathway for expansion of the Pyrus bretschneideri VHA genes (PbrVHA genes). The tissue-specific expression analysis of the pear showed that 36 PbrVHA genes were expressed in major tissues. Seven PbrVHA genes were significantly downregulated when the pollen tube growth stopped. Moreover, many PbrVHA genes were differentially expressed during fruit development and storage, suggesting that VHA genes play specific roles in development and senescence. The present study provides fundamental information for further elucidating the potential roles of VHA genes during development and senescence.

12.
Asian Nurs Res (Korean Soc Nurs Sci) ; 14(5): 306-311, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32916338

RESUMO

PURPOSE: This study explored the mediating effect of career calling in the relationship between family-supportive supervisor behaviors and turnover intention among nurses. METHODS: Data were gathered from 563 nurses enrolled in eight public hospitals in China. They were required to complete measures of family-supportive supervisor behaviors, career calling, and turnover intention. Hierarchical multiple regression analysis and the bootstrapping procedure were used to examine the mediating role of career calling. RESULTS: Family-supportive supervisor behaviors were positively associated with career calling, but negatively associated with turnover intention. Furthermore, career calling partially mediated the relationship between family-supportive supervisor behaviors and turnover intention. CONCLUSION: This study provides strong evidence for an increasing body of work that emphasizes the importance of nursing leaders engaging in family-supportive behaviors for increasing employee career calling and reducing turnover intention.


Assuntos
Escolha da Profissão , Relações Familiares/psicologia , Hospitais Públicos/estatística & dados numéricos , Satisfação no Emprego , Recursos Humanos de Enfermagem Hospitalar/psicologia , Recursos Humanos de Enfermagem Hospitalar/estatística & dados numéricos , Reorganização de Recursos Humanos/estatística & dados numéricos , Adulto , Atitude do Pessoal de Saúde , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Apoio Social , Inquéritos e Questionários
13.
Gene Expr Patterns ; 36: 119113, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32325218

RESUMO

Core browning of 'Whangkeumbae' pear has become an urgent problem in the Chinese pear industry, which often appears after several months of low-temperature storage. However, little is known regarding the crosstalk between physiology and molecular mechanisms regulating the core browning process of the pear. In this study, the physiological and genetic responses of the core were identified during storage. The results showed that the malonyldialdehyde (MDA) content, electrolyte leakage, hydrogen peroxide (H2O2) content and superoxide anion (O2·-) production rate progressively increased during the browning process. Polyphenoloxidase (PPO), phospholipase D (PLD) and lipoxygenase (LOX) activity initially slightly increased but then sharply increased during the later storage stage. A total of 33,265 unigenes was generated via high-throughput sequencing, and 5121 differentially expressed genes (DEGs) were identified. These DEGs were functionally annotated and some core browning-related DEGs involved in the redox reaction, membrane lipid metabolism and enzymatic browning were also determined. We found that the changes in the gene expression accorded with the physiological variation, indicating the close crosstalk between physiological and genetic response during storage. Our study provides a basis for future research on the core browning mechanism during pear storage.


Assuntos
Temperatura Baixa , Armazenamento de Alimentos , Reação de Maillard , Proteínas de Plantas/metabolismo , Pyrus/metabolismo , Transcriptoma , Catecol Oxidase/genética , Catecol Oxidase/metabolismo , Eletrólitos/metabolismo , Frutas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , Peróxido de Hidrogênio/metabolismo , Lipoxigenase/genética , Lipoxigenase/metabolismo , Malondialdeído/metabolismo , Fosfolipase D/genética , Fosfolipase D/metabolismo , Proteínas de Plantas/genética , Pyrus/genética , Superóxidos/metabolismo
14.
J Healthc Eng ; 2020: 1506250, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104556

RESUMO

Discussed in this paper is the tip-over stability analysis of a pelvic support walking robot. To improve the activities of daily living (ADL) in hemiplegic patients, a pelvic support walking robot is proposed to help patients facilitating their rehabilitation. During the gait training with the robot, the abnormal man-machine interaction forces may lead to the tip-over of the robot, which is not beneficial to the rehabilitation process. A new method is proposed to predict the possibility of tipping over and evaluate the stability of the robot based on statics model, dynamics model, and zero-moment point (ZMP) theory. Through the interaction forces and moments analysis with static case, the safe point (ZMP) is studied, and the influence factors of force/moment are analyzed by dynamics case. An optimization algorithm based on the genetic algorithm (GA) is proposed to reduce the risk of tipping over. The simulation results show that the optimization algorithm can keep the robot from tipping over when the interaction forces exceed the safety threshold.


Assuntos
Acidentes por Quedas , Pelve , Robótica , Tecnologia Assistiva , Caminhada , Algoritmos , Previsões/métodos , Humanos , Modelos Teóricos
15.
Mol Plant Pathol ; 17(1): 16-28, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25808544

RESUMO

Fusarium graminearum, the causal agent of Fusarium head blight, is a common pathogen on small grain cereals worldwide and produces various trichothecenes [deoxynivalenol (DON) is predominant] during infection. A previous study has revealed that DON production is positively correlated with the occurrence of carbendazim (MBC) resistance. Here, we identified and characterized two putative genes encoding hexokinase in F. graminearum (FgHXK1 and FgHXK2), which is a rate-limiting enzyme in DON biosynthesis. The expression level of hexokinase genes and the production of pyruvate, which is the precursor of DON, were up-regulated in the MBC-resistant strain, indicating that hexokinase genes might be involved in increased DON production. Phylogenetic and comparative analyses indicated that FgHXK1 was the predominant hexokinase gene. Gene disruption showed that ΔFgHXK1 severely affected DON production, indicating that FgHXK1 played a role in the regulation of DON biosynthesis. Morphological characterization showed that ΔFgHXK1 led to inhibited vegetative growth and conidiation. Sensitivity tests to MBC and various stresses indicated that both ΔFgHXK1 and ΔFgHXK2 mutants showed no significant difference from parental strains. Pathogencity assays showed that ΔFgHXK1 mutants lost virulence on wheat head and corn stigma; however, they showed no change in sexual reproduction. The FgHXK1-overexpressing transformants were obtained subsequently. Their pyruvate and DON production was confirmed to be increased, indicating that FgHXK1 positively regulated DON biosynthesis. Although additional defects appeared in overexpression mutants, MBC sensitivity showed no change. All of the results indicated that the transcriptional level of FgHXK1 regulated DON biosynthesis, but showed no direct relationship with MBC resistance.


Assuntos
Proteínas Fúngicas/metabolismo , Fusarium/enzimologia , Fusarium/crescimento & desenvolvimento , Hexoquinase/metabolismo , Tricotecenos/biossíntese , Benzimidazóis/farmacologia , Carbamatos/farmacologia , Carbono/metabolismo , Sequência Conservada , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Fusarium/patogenicidade , Deleção de Genes , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Genes Fúngicos , Hexoquinase/química , Hexoquinase/genética , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Pressão Osmótica/efeitos dos fármacos , Ácido Pirúvico/metabolismo , Reprodutibilidade dos Testes , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/crescimento & desenvolvimento , Virulência/efeitos dos fármacos , Zea mays/efeitos dos fármacos , Zea mays/microbiologia
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