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1.
Health Commun ; : 1-12, 2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32633142

RESUMO

This study explores hospital workers' experiences with workplace communication overload and its implications for effective safety and risk messaging in hospital organizations. We use a multi-step thematic analysis of interview (N = 12) and focus group (N = 8, 28 participants) data collected from hospital workers to analyze how they describe specific organizational communication channels influencing their communication overload. We specifically examine how workers' socially constructed channel affordances and constraints for sending/receiving safety information provide meaning to their communicatively overloaded states. Hospital workers explained that asynchronous channels such as e-mail and voicemail aggravated communication overload, while synchronous channels such as team huddles alleviated it. We discuss the implications of these results for the communication overload model by pointing to violations of communication channel preference and literature on the social affordances of communication channels. Study limitations and future directions are offered.

2.
Am J Pharm Educ ; 84(1): 7250, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32292193

RESUMO

Objective. To deliver a brief, applied workshop in improvisational communication skills during the new student orientation for first-year Doctor of Pharmacy students and to assess students' perceptions about the experience. Methods. Communication instructors developed a two-hour communication "boot camp" based on established principles of clear, responsive, flexible communication. They taught core skills through interactive applied improvisational exercises and facilitated debriefings. A questionnaire was administered following the workshop that asked students to rate the quality of the session and comment on its strengths and weaknesses. Results. Of the 124 students who participated in the workshop, 95 (77%) completed evaluations at the end. Their feedback was generally favorable: 90% of participants indicated that the boot camp improved their communication skills and 92% agreed that the activities were realistic and relevant to real-life scenarios. The students reported that they valued the chance to connect with classmates, learn how to adapt to different audiences, and explore how communication skills would be useful in professional settings. Conclusion. This interactive program delivered valuable content in a short period of time. Student feedback suggested that they valued the expertise of communication instructors and the playful, active method of learning. The creation of the workshop was labor-intensive because of the formative research that guided it.

3.
Health Commun ; : 1-11, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31931622

RESUMO

Supportive social ties positively impact cancer patients' health; however, little is known about the intertwined links between both offline and online ties, and individual and group ties. Using the common-identity/common-bond approach, we empirically tested the critical difference that individual and group ties exert on health across offline and online settings. Results from 356 female breast cancer patients showed group ties affect quality of life through sequential group identification and social support, while individual ties affect quality of life through sequential interpersonal bonds and social support. Offline group and online individual ties are stronger predictors of quality of life than online group and offline individual ties. A cluster analysis categorized participants into four distinguishable segments. People with stronger offline interpersonal bonds and online group identification reported a better quality of life. This offers insight into the social dynamics that are most consequential for health, and the potential theoretical pathways through which they operate.

4.
Nat Commun ; 11(1): 305, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949160

RESUMO

Surface and subsurface are commonly considered as separate entities because of the difference in the bonding environment and are often investigated separately due to the experimental challenges in differentiating the surface and subsurface effects. Using in-situ atomic-scale transmission electron microscopy to resolve the surface and subsurface at the same time, we show that the hydrogen-CuO surface reaction results in structural oscillations in deeper atomic layers via the cycles of ordering and disordering of oxygen vacancies in the subsurface. Together with atomistic calculations, we show that the structural oscillations in the subsurface are induced by the hydrogen oxidation-induced cyclic loss of oxygen from the oxide surface. These results demonstrate the propagation of the surface reaction dynamics into the deeper layers in inducing nonstoichiometry in the subsurface and have significant implications in modulating various chemical processes involving surface-subsurface mass transport such as heterogeneous catalysis, oxidation, corrosion and carburization.

5.
Sci Total Environ ; 711: 135141, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31822401

RESUMO

Water supply safety of riverbank filtration wells (RBFWs) have attracted a great deal of attention in recent years as their role in water supply is increasingly valued. In this study, this issue was revealed from the perspective of water level, quality and supply capacity of RBFWs based on an interference-pumping test with three pumping wells near the Songhua River in Northeast China followed by a recovery test. The results showed that a stable cone of depression of groundwater level in the riverbank filtration (RBF) formed after pumping for about five days with the maximum drawdown of the groundwater level of 10.42 m. The corresponding water capacity of the well group maintained 2.78 × 104 m3/d from then until the end of the test, 60% of which were captured directly from the river. The groundwater level could return to the level before the pumping test after the pumping test stopped for one day. The RBF could provide turbidity, trace organic substances and major cations and anions (except for Ca2+ and Mg2+) pre-treatment of the river water with the removal rates of 29%-95% for some water quality indicators. However, limited improvement of water quality was observed with respect to some inorganic contaminants (Fe, Mn and NH4+-N) because the background concentrations of them in the groundwater were higher than in the river water. When compared with the impact on water level and supply capacity, the impact of the surface water-groundwater interaction on the mechanisms of water quality evolution was more complicated. Taken together, the results of this study indicate that RBFWs can ensure a sustainable water supply of stable quality, which can also simplify the post-treatment processes of waterworks and reduce costs.

6.
Opt Express ; 27(16): 22161-22172, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31510511

RESUMO

Iterative point-wise reinforcement learning (IPWRL) is proposed for highly accurate indoor visible light positioning (VLP). By properly updating the height information in an iterative fashion, the IPWRL not only effectively mitigates the impact of non-deterministic noise but also exhibits excellent tolerance to deterministic errors caused by the inaccurate a priori height information. The principle of the IPWRL is explained, and the performance of the IPWRL is experimentally evaluated in a received signal strength (RSS) based VLP system and compared with other positioning algorithms, including the conventional RSS algorithm, the k-nearest neighbors (KNN) algorithm and the PWRL algorithm where iterations exclude. Unlike the supervised machine learning method, e.g., the KNN, whose performance is highly dependent on the training process, the proposed IPWRL does not require training and demonstrates robust positioning performance for the entire tested area. Experimental results also show that when a large height information mismatch occurs, the IPWRL is able to first correct the height information and then offers robust positioning results with a rather low positioning error, while the positioning errors caused by the other algorithms are significantly higher.

7.
Front Neurorobot ; 13: 59, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31427942

RESUMO

Synchronization of coupled non-linear oscillators inspired by a central pattern generator (CPG) can control the bionic robot and promote the coordination and diversity of locomotion. However, for a robot with a strong mutual coupled structure, such neurobiological control is still missing. In this contribution, we present a σ-Hopf harmonic oscillator with decoupled parameters to expand the solution space of the locomotion of the robot. Unlike the synchronization of original Hopf oscillators, which has been fully discussed, the asymmetric factor of σ-Hopf oscillator causes a deformation in oscillation waveform. Using the non-linear synchronization theory, we construct the transition state model of the synchronization process to analyze the asymmetrical distortion, period change and duty ratio inconsistency. Then a variable coupling strength is introduced to eliminate the waveform deformation and maintain the fast convergence rate. Finally, the approach is used for the locomotion control of a bionic parallel waist of legged robot, which is a highly coupled system. The effectiveness of the approach in both independent and synthesis behavior of four typical motion patterns are validated. The result proves the importance of controllability of the oscillation waveform and the instantaneous state of the synchronization, which benefits the transition and transformation of the locomotion and makes the coupling motion more flexible.

8.
Materials (Basel) ; 12(13)2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31277351

RESUMO

Recycled aggregates have high water absorption and crushing index. In order to improve the properties of recycled aggregates in concrete production, various treatments were used to modify the aggregates. In recent years, bio-deposition as a new treatment method of recycled aggregates was environmentally friendly. An improved method of bio-deposition was implemented to modify the properties of recycled mortar aggregates (RMA). O-bio-deposition is based on aerobic bacteria induced CaCO3 precipitation by respiration by varying the distance between the RMA and the bottom of the container and by adding an oxygen release compound to the culture solution that contains bacteria to promote the induction of CaCO3. First, the physical properties, including water absorption, crushing value, and apparent density, of the coarse RMA under different treatment methods were determined, and an o-bio-deposition treatment method was obtained. The fine RMA was treated and compared with the untreated RMA. Concretes were then prepared from the treated coarse RMA, and compressive strength and slump were determined. In addition, the effect of the o-bio-deposition treatment on the RMA surface and the micro-cracks of concretes were observed by scanning electron microscopy (SEM). It was found that the water absorption and crushing index of the coarse RMA treated by o-bio-deposition were reduced by 40.38 and 19.76% compared with untreated RMA, respectively. Regarding the concrete, the slump and the compressive strength (28 d) of concrete were increased by 115% and 25.3%, respectively compared with the untreated concrete.

9.
Phys Chem Chem Phys ; 21(12): 6381-6390, 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30838369

RESUMO

To ensure the safety and efficiency of engineered subsurface operations, it is vital to understand impacts of aqueous chemistries on brine-mineral interactions in subsurface environments. In this study, using biotite as a model phyllosilicate, we investigated the effects of sulfate on its interfacial reactions under subsurface relevant conditions (95 °C and 102 atm of CO2). By making monodentate mononuclear complexes with biotite surface sites, 50 mM sulfate enhanced biotite dissolution by 40% compared to that without sulfate. However, sulfate at lower concentrations than 50 mM did not obviously affect biotite dissolution. In addition, sulfate did not impact secondary mineral precipitation. However, even without any discernible surface morphological change, sulfate adsorption made biotite surfaces more hydrophilic. To provide a more comprehensive perspective on environmentally-abundant ligands, we further comparatively examined the effects of various inorganic (e.g., sulfate and phosphate) and organic ligands (e.g., acetate, oxalate, and phosphonates) on biotite interfacial interactions and assessed their impacts on physico-chemical properties. We found that the presence of phosphate and phosphonates significantly promoted precipitation of Fe- and Al-bearing secondary minerals, but sulfate, acetate, and oxalate did not. Biotite surface wettability was also altered as a result of changes in biotite surface functional groups and surface charges by ligand adsorption: sulfate, oxalate, phosphate, and phosphonate made biotite more hydrophilic, while acetate made it less hydrophilic. This study provides useful new insights into the effects of brine chemistries on brine-mineral interactions, enabling safer and more efficient engineered subsurface operations.

10.
Sensors (Basel) ; 18(9)2018 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-30149656

RESUMO

In view of terrain classification of the autonomous multi-legged walking robots, two synthetic classification methods for terrain classification, Simple Linear Iterative Clustering based Support Vector Machine (SLIC-SVM) and Simple Linear Iterative Clustering based SegNet (SLIC-SegNet), are proposed. SLIC-SVM is proposed to solve the problem that the SVM can only output a single terrain label and fails to identify the mixed terrain. The SLIC-SegNet single-input multi-output terrain classification model is derived to improve the applicability of the terrain classifier. Since terrain classification results of high quality for legged robot use are hard to gain, the SLIC-SegNet obtains the satisfied information without too much effort. A series of experiments on regular terrain, irregular terrain and mixed terrain were conducted to present that both superpixel segmentation based synthetic classification methods can supply reliable mixed terrain classification result with clear boundary information and will put the terrain depending gait selection and path planning of the multi-legged robots into practice.

11.
J Hazard Mater ; 358: 427-433, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-30014932

RESUMO

To determine the effects of dietary constituents on soil Pb oral bioavailability, Pb relative bioavailability (RBA) in 3 soils contaminated by zinc smelting (ZS), wire-rope production (WR), and metal mining (MM) was measured under fasted and fed states with 9 foods. Under fasted state, Pb-RBA was 84.4 ±â€¯10.3, 82.6 ±â€¯4.70, and 32.3 ±â€¯1.10% for ZS, WR, and MM soils; however, it decreased by 1.3-3.5 fold to 23.9-58.8, 25.6-49.9, and 14.8-24.2% under fed states with foods excluding Pb-RBA with egg in WR soil (97.3 ±â€¯4.46%), and with cabbage and egg in MM soil (40.0 ±â€¯8.62 and 44.4 ±â€¯0.96%). In the presence of foods, egg and pork with significantly higher protein and fat contents leaded to the highest soil Pb-RBA (44.4-97.3%), while Pb-RBA determined with mineral-rich mouse feed was 1.6-7.9 fold lower (9.41-13.5%), suggesting high fat and protein foods tended to increase soil Pb-RBA, while high mineral diets decreased soil Pb-RBA. The increased Pb-RBA of MM soil with cabbage compared to fasted state was due to high organic content in cabbage, which could increase soil Pb solubility by inhibiting Fe and Pb co-precipitation in the intestine. For accurate assessment of health risks of contaminated soils, dietary influence on soil Pb-RBA should be considered.


Assuntos
Alimentos , Chumbo/farmacocinética , Poluentes do Solo/farmacocinética , Animais , Disponibilidade Biológica , Feminino , Privação de Alimentos , Fígado/metabolismo , Camundongos Endogâmicos BALB C
12.
J Phys Chem B ; 122(2): 855-863, 2018 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-29091455

RESUMO

The role of oxygen in the activation of C-H bonds in methane on clean and oxygen-precovered Cu(111) and Cu2O(111) surfaces was studied with combined in situ near-ambient-pressure scanning tunneling microscopy and X-ray photoelectron spectroscopy. Activation of methane at 300 K and "moderate pressures" was only observed on oxygen-precovered Cu(111) surfaces. Density functional theory calculations reveal that the lowest activation energy barrier of C-H on Cu(111) in the presence of chemisorbed oxygen is related to a two-active-site, four-centered mechanism, which stabilizes the required transition-state intermediate by dipole-dipole attraction of O-H and Cu-CH3 species. The C-H bond activation barriers on Cu2O(111) surfaces are large due to the weak stabilization of H and CH3 fragments.

13.
J Health Commun ; 22(12): 974-980, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29173072

RESUMO

Despite widespread understanding of the benefits of physical activity, many adults in the United States do not meet recommended exercise guidelines. Burgeoning technologies, including wearable fitness trackers (e.g., Fitbit, Apple watch), bring new opportunities to influence physical activity by encouraging users to track and share physical activity data and compete against their peers. However, research has not explored the social processes that mediate the relationship between the use of wearable fitness trackers and intention to exercise. In this study, we applied the Theory of Planned Behavior (Ajzen, 1991) to explore the effects of two communicative features of wearable fitness devices-social sharing and social competing-on individuals' intention to exercise. Drawing upon surveys from 238 wearable fitness tracker users, we found that the relationship between the two communication features (social sharing and competing) and exercise intention was mediated by attitudes, subjective norms, and perceived behavioral control. The results suggest that the ways in which exercise data are shared significantly influence the exercise intentions, and these intentions are mediated by individuals' evaluation of exercise, belief about important others' approval of exercise, and perceived control upon exercise.


Assuntos
Exercício Físico/psicologia , Monitores de Aptidão Física , Rede Social , Adulto , Comportamento Competitivo , Feminino , Humanos , Intenção , Masculino , Teoria Psicológica , Inquéritos e Questionários
14.
Sensors (Basel) ; 17(12)2017 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-29168742

RESUMO

Abstract: In order to find a common approach to plan the turning of a bio-inspired hexapod robot, a locomotion strategy for turning and deviation correction of a hexapod walking robot based on the biological behavior and sensory strategy of ants. A series of experiments using ants were carried out where the gait and the movement form of ants was studied. Taking the results of the ant experiments as inspiration by imitating the behavior of ants during turning, an extended turning algorithm based on arbitrary gait was proposed. Furthermore, after the observation of the radius adjustment of ants during turning, a radius correction algorithm based on the arbitrary gait of the hexapod robot was raised. The radius correction surface function was generated by fitting the correction data, which made it possible for the robot to move in an outdoor environment without the positioning system and environment model. The proposed algorithm was verified on the hexapod robot experimental platform. The turning and radius correction experiment of the robot with several gaits were carried out. The results indicated that the robot could follow the ideal radius and maintain stability, and the proposed ant-inspired turning strategy could easily make free turns with an arbitrary gait.

15.
Health Commun ; 32(3): 261-268, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27218673

RESUMO

With the growth in workplace health promotion (WHP) initiatives, organizations are asking employees to enact their personal health identities at work. To understand this prominent yet poorly understood phenomenon, we surveyed 204 employees at a company with a WHP program and found that participation in the wellness program mediated personal health and organizational identities. Results fill a gap in communication literature by demonstrating the effect of individual identity enactment on organizational identification and contribute to recent research stressing the relationship between identity and health behaviors. In addition, findings illuminate the role of situated activity in identity negotiation, suggesting that certain activities in organizations, like wellness programs, serve as identity bridges between personal and work-related identity targets.


Assuntos
Comunicação em Saúde , Promoção da Saúde , Identificação Social , Local de Trabalho/psicologia , Adulto , Feminino , Humanos , Masculino , Inquéritos e Questionários
16.
Sensors (Basel) ; 16(9)2016 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-27589766

RESUMO

Aimed at solving the misplaced body trajectory problem caused by the rolling of semi-round rigid feet when a robot is walking, a legged kinematic trajectory correction methodology based on the Least Squares Support Vector Machine (LS-SVM) is proposed. The concept of ideal foothold is put forward for the three-dimensional kinematic model modification of a robot leg, and the deviation value between the ideal foothold and real foothold is analyzed. The forward/inverse kinematic solutions between the ideal foothold and joint angular vectors are formulated and the problem of direct/inverse kinematic nonlinear mapping is solved by using the LS-SVM. Compared with the previous approximation method, this correction methodology has better accuracy and faster calculation speed with regards to inverse kinematics solutions. Experiments on a leg platform and a hexapod walking robot are conducted with multi-sensors for the analysis of foot tip trajectory, base joint vibration, contact force impact, direction deviation, and power consumption, respectively. The comparative analysis shows that the trajectory correction methodology can effectively correct the joint trajectory, thus eliminating the contact force influence of semi-round rigid feet, significantly improving the locomotion of the walking robot and reducing the total power consumption of the system.

17.
Sci Total Environ ; 532: 803-11, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26136157

RESUMO

Few studies have assessed As bioaccessibility in housedust using different in vitro assays and compared to those in contaminated soils. We determined As bioaccessibility in 24 housedust samples (4.48-38.2 mg kg(-1)) using SBRC, IVG, DIN, and PBET assays and they averaged 73, 68, 53, and 48% in the gastric phase and 26, 46, 55 and 43% in the intestinal phase of the 4 assays. The corresponding As bioaccessibility in 34 As-contaminated soils (22-6899 mg kg(-1)) were 34, 25, 22, and 22% in the gastric phase and 18, 19, 21, and 20% in the intestinal phase, which was 1.5-2.7 fold lower than those in housedust possibly due to differences in contamination sources and properties. Based on the gastric phase of SBRC assay, As bioaccessibility was 44-96% in housedust and 2.3-80% in soils. Variation in As bioaccessibility among assays was similar for housedust and soils, with SBRC assay providing the highest bioaccessibility in gastric phase. In intestinal phase, dissolved As was probably adsorbed onto precipitated iron oxides, causing a sharp decrease in As bioaccessibility by SBRC assay. Unlike SBRC assay, gastric constituents (pepsin, mucin, phosphate, and citrate) in other 3 assays inhibited As adsorption and/or enhanced As dissolution, leading to greater As bioaccessibility. The greater As bioaccessibility in housedust than soil suggests the potential of greater health risk from As exposure to housedust than soil.


Assuntos
Arsênico/análise , Poeira/análise , Exposição Ambiental/análise , Poluentes do Solo/análise , Exposição Ambiental/estatística & dados numéricos , Humanos
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