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1.
This study used two dimensional biomechanical analysis to examine the effects of back belts and lifting load on selected lifting kinematics during a simulated patient transfer. A human manikin placed in a sitting position was attached to a customized lifting apparatus which controlled the lifting load and direction of the manikin. Eighteen female participants, between the age of 21 and 27, completed six lifts (sit to stand transfers) of the manikin. Three lifts were completed at the 30 lb load condition (no belt, belt 1 and belt 2) and three lifts were completed at the 50 lb load condition (no belt, belt 1 and belt 2). A doubly two way ANOVA found a significant main effect for the belt condition, F(12,6)=10.06, P=0.002. There was no significant effect for load and no interaction existed between belt and load. The results revealed a significant decrease in trunk flexion when participants wore the wider (nine inch) belt during the 30~lb lifts when compared to the no belt trials. No significant differences were found in trunk flexion means with the narrower width (six inch) belt. No significant differences were found in trunk spinal flexion with either belt condition during the 50 lb lifts. There were no significant differences found in either of the belts in the means of lifting time, knee flexion, elbow flexion, forward displacement of the lifter's center of mass, and the lifter's maximum center of mass velocity. The results suggest that wider back belts may be more effective at reducing spinal flexion during patient lifting under moderate load conditions when compared to narrower back belts and to no-belted controls.  相似文献   

2.
Ai T 《Work (Reading, Mass.)》2012,41(Z1):1588-1593
There has been limited attention given to the physiological demands of pushing and pulling, especially in industrially developing countries such as South Africa. Two key factors affecting the physiological demands of these tasks are the hand forces exerted and the start/stop frequency. The purpose of the current study was therefore to investigate the physiological responses to pushing and pulling at various loads and start/stop frequencies. 36 male subjects participated in the study and were required to complete a total of 18 conditions (three techniques: pushing, two- and one-handed pulling; three loads: 200, 350 and 500 kg; and two frequencies: 2 and 4 stops per minute). During each condition the heart rate, oxygen uptake and energy expenditure were measured. Pushing was found to elicit significantly lower responses for all three dependent variables than either form of pulling. The start/stop frequency was also found to have a significant impact on subject responses. The findings of this study indicate that the technique adopted to maneuver loads is critical in determining the physical demands placed on the human operator. Furthermore increasing the frequency of start/stops plays an important role, thus the forces exerted during these two phases are important from a physiological perspective.  相似文献   

3.
There is an increasing interest in alpha-range rhythms in the electroencephalogram (EEG) in relation to perceptual and attentional processes. The infant mu rhythm has been extensively studied in the context of linkages between action observation and action production in infancy, but less is known about the mu rhythm in relation to cross-modal processes involving somatosensation. We investigated differences in mu responses to cued vibrotactile stimulation of the hand in two age groups of infants: From 6 to 7 months and 13 to 14 months. We were also interested in anticipatory neural responses in the alpha frequency range prior to tactile stimulation. Tactile stimulation of infants’ left or right hand was preceded by an audiovisual cue signaling which hand would be stimulated. In response to the tactile stimulus, infants demonstrated significant mu desynchronization over the central areas contralateral to the hand stimulated, with higher mu peak frequency and greater contralateral mu desynchronization for older infants. Prior to the tactile stimulus, both age groups showed significant bilateral alpha desynchronization over frontocentral sites, which may be indicative of generalized anticipation of an upcoming stimulus. The findings highlight the potential of examining the sensorimotor mu rhythm in the context of infant attentional development.  相似文献   

4.
This article investigates how the social media site Reddit hindered the collective action efforts stemming from the Gamergate controversy. Using forum posts from two time-points, one early in the movement and another six months later, this work describes how the Reddit platform impeded movement efforts over time. More specifically, we examine how the nature of Reddit discussions created barriers to each of three key movement processes: narrative construction of collective identity, framing, and boundary work. We argue that unlike social media platforms such as Facebook, some sites–Reddit in this case–may negatively impact movement success depending on its structure. We also discuss the importance of differing ICT structures and implications for online interactions more generally.  相似文献   

5.
Previous research on work after stroke has used quantitative methods and a medical model approach to identify factors that influence return to work. This study uses an inclusive, qualitative methodology (focus groups) to begin to explore stroke survivors' own perspectives about what helps and hinders paid or voluntary work after stroke. The research was conducted in partnership with Different Strokes, a British organisation of stroke survivors. Five focus group discussions were held with 37 stroke survivors and 12 of their supporters. Data was analysed using an adapted Framework approach to identify themes within and across individuals and groups. Factors representing barriers to or enablers of work were identified in four key themes: rehabilitation process, employer agency, social structural and personal. The study found evidence of social oppression via infrastructure, institutional structures and practices, and some individuals' attitudes. Alongside this, some supportive individuals, practices and strategies were identified.  相似文献   

6.
Lifting and carrying heavy loads occur frequently among ironworkers and result in high prevalence and incidence rates of low back complaints, injuries and work-disability. From a health perspective, little information is available on the effect of team lifting on work demands and workload. Therefore, the objective of this study was to compare the effects of team lifting of maximally 50 kg by two ironworkers (T50) with team lifting of maximally 100 kg by four ironworkers (T100). This study combined a field and laboratory study with the following outcome measures: duration and frequency of tasks and activities, energetic workload, perceived discomfort and maximal compression forces (Fc peak) on the low back. The physical work demands and workload of an individual iron worker during manual handling of rebar materials of 100 kg with four workers did not differ from the manual handling of rebar materials of 50 kg with two workers, with the exception of low back discomfort and Fc peak. The biomechanical workload of the low back exceeded for both T50 and T100 the NIOSH threshold limit of 3400N. Therefore, mechanical transport or other effective design solutions should be considered to reduce the biomechanical workload of the low back and the accompanying health risks among iron workers.  相似文献   

7.
Models, in the sense of loosely entertained clusters of beliefs, attitudes, assumptions and expectations which direct the work of researchers and clinicians, also act as perceptual filters, tending to focus the attention of those who use them on certain aspects of reality and relegating to the background or ignoring altogether other aspects of the field of study and action. The central characteristics of social learning and of medical models are briefly reviewed and they are compared as perceptual filters for their distorting effects on research in gambling and in gambling addictions and on intervention strategies for problem gamblers. It is concluded that the exclusive predominance of any one model leads to the impoverishment of both research and intervention.  相似文献   

8.
9.
The focus of this study is a human's ability to make full use of listening and hearing. This ability consists of dividing auditory information into a signal and a noise. To evaluate the risk of using headphones, the study investigated the auditory perception when a warning sound is given in the presence of environmental noise.  相似文献   

10.
The incidence of low back pain has continued to increase in modern society, despite the considerable amount of scientific research that has aimed to isolate its exact aetiology. Although low back pain is still largely idiopathic, research has identified over one hundred risk factors for the condition. Of these risk factors, manual material handling tasks are perhaps the most widely explored within the biomechanical literature, as these tasks have been associated with high mechanical stresses on the lower back. Numerous technique-related variables have been addressed by researchers, whilst the influence of intra-abdominal pressure has also been considered. In addition to this, the implications of variations in the size and structural composition of the load have also been assessed. However, low back pain continues to pose a significant threat to the financial stability and happiness of millions of people worldwide. In addition, a number of functional work capacity assessment tests use lifting as a method for assessment of return to work condition. Many of these tests are not standardised and do not consider the implications of low back loading. Therefore new research attempts in this area are justified and should aim to identify the extent of the association that exists between the known risk factors and the incidence of low back pain.  相似文献   

11.
Although they have a recent work history, 70 to 80% of adults with multiple sclerosis are unemployed following their diagnosis. This high rate of unemployment constitutes a great loss of potential to the American economy. To help individuals with multiple sclerosis (MS) return to work or retain employment, rehabilitation professionals must understand the barriers resulting in unemployment and implement interventions to reduce or remove those concerns. In this article, Hershenson's systemic model of rehabilitation counseling is presented as a diagnostic scheme for identifying barriers to employment. Counselor consultation on barrier removal via reasonable accommodation is presented as one example of a rehabilitation intervention consistent with the systemic diagnostic model.  相似文献   

12.
Recent sociological works establish the significance and role of the state and political sphere in the enactment of racial oppression and construction of racial categories. However, less understood are the racialized dynamics that mediate exclusion and access to political power, particularly at the meso‐ and micro‐levels. Synthesizing extant theory and research on racial inequality, the state, politics, and power, this article advances a framework centering on boundaries and barriers. First, it discusses the relationship between the state and political sphere, political power, and racial inequality. Next, it explores the literature on the deployment and contestation of racialized boundaries to the symbolic and material benefits of the state. It then examines the literature on racialized barriers to engagement, participation, and influence in the political sphere . The article concludes by suggesting future research in the related areas of agenda‐setting and influence and the microdynamics of political power.  相似文献   

13.
Regenwetter and Grofman [17] offer a probabilistic generalization of Sen's [25, 27] classic value restriction condition when individual preferences are linear orders. They provide necessary and sufficient conditions for transitive majority preferences on linear orders. They call these conditions net value restriction and net preference majority. We study parallel generalizations for general binary relations. In general, neither net value restriction nor net preference majority is necessary for transitive majority preferences. Net value restriction is sufficient for transitive strict majority preferences, but not sufficient for transitive weak majority preferences. Net majority is sufficient for transitive majorities only if the preference relation with a net majority is a weak order. An application of our results to four U.S. National Election Study data sets reveals, in each case, transitive majorities despite a violation of Sen's original value restriction condition. We thank the National Science Foundation for funding this collaborative research through NSF grants SBR 97-30076 to Regenwetter and SBR 97-30578 to Grofman and Marley. We are indebted to the Interuniversity Consortium for Political and Social Research (ICPSR) for access to the 1968, 1980, 1992 and 1996 U.S. National Election Study (NES) data. We thank Mark Berger for helping us with the necessary data extraction. We are grateful to the action editor and the referees for extensive and helpful comments. Most of this work was carried out while the first author was a faculty member at the Fuqua School of Business, Duke University, which has generously supported our collaboration. Marley was a fellow at the Hanse-Wissenschaftskolleg, Germany, during the paper's completion.  相似文献   

14.
There are still fewer female than male managers in Norway's state bureaucracy. This article asks if there are organizational barriers which prevent women from entering these positions. Is there really a glass ceiling, or must one look outside the organizational environment to find an explanation? Is it rather the case that the scarcity of female managers is caused by women's own preferences or their life situations outside work? Or do both contribute to the situation? The study shows that female managers are treated just as well as male managers in central parts of the state bureaucracy. Employers give equal shares of respect and attention to both genders. Female managers are encouraged to apply for the same number of jobs as men and are offered an equal number of jobs as men when they apply; in fact, women are offered more jobs than men, when one controls for the number of job applications. This indicates that organizational barriers are not the problem. The study also shows that there are no differences in work orientation between male and female managers. Female managers are just as ambitious as male managers. Nor do female managers find it more difficult than male managers to combine work and family life. So, how can one explain the low number of female managers? The study shows that one reason can be that female managers apply for management jobs less often than their male colleagues. The cause of this seems to be anticipated discrimination rather than lack of ambition or self‐confidence. However, this slows down women's movement into higher management positions in the state bureaucracy.  相似文献   

15.
This study assessed the relative influence of psychological barriers, SES, and ethnic differences in mammography use for a community sample of 586 White, 227 Black, and 150 Hispanic women. Confirmatory factor analyses with latent variables indicated plausible factor structures for all groups on items related to barriers to mammography. Summed indicators of SES, fear of radiation, embarrassment, pain, anxiety, and cost concerns were correlated significantly with mammography use for the pooled group. Separate analyses by ethnicity indicated a substantial relationship between mammography use and cost concerns by White and Black women, and fear of pain by Black and Hispanic women. Use of mammography was associated more highly with SES among Hispanic women. Pooled logistic regression analyses controlling for SES and ethnicity showed that the psychological barriers, especially concern about cost, remained important independent predictors of mammography use. We explore sociocultural explanations for less mammography use by Hispanic women, especially those less acculturated.  相似文献   

16.
Homework is a therapeutic process that has strong theoretical and empirical basis, but existing research has focused on "compliance" rather than considering the broader and more clinically meaningful construct of "engagement." Absent in the literature is empirical study of the barriers to engagement or study of homework use among couple and family therapists (CFTs). The current study investigates the frequency and type of homework, as well as the influence of homework compliance, quality of compliance, and experience of barriers to compliance on CFTs' attitudes and beliefs toward barriers to homework completion for couples and families. Results indicated CFTs (N=226 AAMFT Clinical members) use homework more often with couples than with families, and CFTs report greater homework compliance and quality of compliance for couples when compared to families. A path analysis examining compliance, quality of compliance, and barriers to compliance as predictors of attitudes/beliefs toward barriers revealed no significant findings. A discussion presents implications for future research and practice for homework in couple and family therapy.  相似文献   

17.
李雪 《科学发展》2012,(5):81-91
目前我国基本养老保险统筹存在层次上的区域障碍,不同地区在经济水平、基本养老保险历史债务和现状等方面的巨大差距严重制约着基本养老保险统筹层次的提高,因此,适当降低地区间收入再分配的幅度,需要对在岗职工平均工资进行较长时期分步调节,以实现较小幅度的收入转移代价,这将有利于减小基本养老保险全国统筹实现的阻力。  相似文献   

18.
Advice and training on techniques for lifting is frequently provided. The choice of which technique to use should be based on the evidence available on a number of criteria. Important criteria include: psychophysical, physiological, biomechanical, psychological, performance and clinical. However few professionals have the time to read all the original research required to understand the limitations of the available criteria. The purpose of this paper was to present an accessible synthesis of the criteria used to choose a specific technique. Each criterion is described and its validity discussed to provide the reader with a better understanding of the criteria, and thus the evidence available.  相似文献   

19.
20.
This article reports results of the first migration study covering the entire State of Kerala. It encompasses both measurement as well as analysis of the various types and facets of migration. Migration has been the single most dynamic factor in an otherwise dreary development scenario in Kerala during the last quarter of the twentieth century. Kerala is approaching the end of the millennium with a little cheer in many people's homes as a result of migration which has contributed more to poverty alleviation than any other factor, including agrarian reforms, trade union activities and social welfare legislation. The study shows that nearly 1.5 million Keralites now live outside India. They send home more than Rs.4,000 million a year by way of remittances. Three‐quarters of a million former emigrants have come back. They live mostly on savings, work experience, and skills acquired while abroad. More than a million families depend on an internal migrant's earnings for subsistence, children's education and other economic requirements. Whereas the educationally backward Muslims from the Thrissur‐Malappuram region provide the backbone of emigration, it is the educationally forward Ezhawas, Nairs and Syrian Christians from the former Travancore‐Cochin State who form the core of internal migration. The article also analyses the determinants and consequences of internal and external migration. It offers suggestions for policy formulation directed at optimum utilization of remittances sent home by emigrants and the expertise brought back by the return migrants. Migration in Kerala began with demographic expansion, but it will not end up with demographic contraction. Kerala has still to develop into an internally self‐sustaining economy. The prevailing cultural milieu in which its people believe that anything can be achieved through agitation, and any rule can be circumvented with proper political connections, must change and be replaced by a liberalized open economy with strict and definite rules of the game.  相似文献   

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