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1.
Indian J Occup Environ Med ; 21(1): 18-22, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29391743

RESUMO

AIMS: The purpose of this study was to evaluate web-based Knowledge, Attitude and Practice (KAP) intervention on office ergonomics - a unique method for prevention of musculoskeletal discomfort (MSD) - in corporate offices that influences behavior modification. BACKGROUND: With the increasing use of computers, laptops and hand-held communication devices globally among office employees, creating awareness on office ergonomics has become a top priority. Emphasis needs to be given on maintaining ideal work postures, ergonomic arrangement of workstations, optimizing chair functions, as well as performing desk stretches to reduce MSD arising from the use of these equipment, thereby promoting safe work practices at offices and home, as in the current scenario many employees work from home with flexible work hours. Hence, this justifies the importance of our study. OBJECTIVE: To promote safe working by exploring cost-effective communication methods to achieve behavior change at distant sites when an on-site visit may not be feasible. MATERIALS AND METHODS: An invitation was sent by the Medical and Occupational Health Team of a multinational corporation to all employees at their offices in Sri Lanka, Singapore, and Malaysia to take up an online Nordic questionnaire, a screening tool for musculoskeletal symptoms, shared in local languages on two occasions - baseline evaluation (n = 240) and a follow-up evaluation after 3 months (n = 203). After completing the baseline questionnaire, employees were immediately trained on correct postures and office ergonomics with animation graphics. The same questionnaire was sent again after a 12-week gap only to those employees who responded to the baseline questionnaire on initial assessment. STATISTICAL ANALYSIS USED: Data collected were analyzed using the Statistical Package for the Social Sciences (SPSS) version 20.0 software and variables were compared using odds ratio as well as Chi-square test. RESULTS: Of the 203 employees who responded, 47.35% had some musculoskeletal symptoms. Among them 58.7% had lower back pain, 46.9% had upper back pain, 44.1% had wrist pain, 39.5% had shoulder pain, and 37% had knee pain. The percentages are high as some participants had multiple complaints i.e. 2 or 3 complaints. However, only 40% of these employees had ongoing symptoms at the time of evaluation (past 7 days). A subsequent 3-month evaluation after web-based intervention showed a significant 41-50% decline in ongoing symptoms. CONCLUSIONS: We conclude that newer technology using web-based animation graphics is a highly efficient technique to create office ergonomics awareness and has the potential to become a best practice in countries where language is a communication barrier and an on-site visit may not be feasible due to meagre resources.

2.
Indian J Occup Environ Med ; 21(2): 77-83, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29540968

RESUMO

BACKGROUND: Use of laptops and hand-held devices increase the risk of musculoskeletal disorders (MSDs). More time spent on this activity adopting faulty postures, higher the risk of developing such injuries. This study addresses training on office ergonomics with emphasis on sustainable behavior change among employees to work in safe postures, as this is a top priority in the corporate environment, today. AIM: To explore training intervention methods that ensure wider coverage of awareness on office ergonomics, thereby promoting safer working and suggesting sustainable programs for behavior change and job enrichment. MATERIALS AND METHODS: A cross-sectional study was conducted (2012 - 2017), encompassing corporate office employees of multinational corporations selected from India, Dubai (U.A.E), Nairobi (East Africa), Durban (South Africa), South East Asian countries (Philippines, Vietnam, Indonesia, Singapore, Malaysia, Thailand and Sri Lanka).Participant employees (n = 3503) were divided into two groups to study the effect of interventions'; i.e., (a) deep training: 40 minute lecture by the investigator with a power point presentation (n = 1765) using a mock workstation and (b) quick training: live demonstrations of 10 minutes (n = 1738) using a live workstation. RESULTS: While deep training enhanced awareness in 95.51% and quick training in 96.59% globally, the latterwas much appreciated and educated maximum employees. From statistical analysis, quick training was found superior in providing comprehensive training and influencing behavior modification in India, but all over the world it was found highly superior in knowledge enlargement, skills enrichment in addition to providing comprehensive training (P < 0.05). In countries, located to West of India, it significantly influenced behavior modification. CONCLUSION: As because few employees attend deep training lectures, the quick 10-minute program is highly promising as it is practical, replicable, yields increased awareness with wider employee coverage in a much shorter time, instilling a feeling of caring and confidence amongst them towards a robust office ergonomics program. This could lead to propose as a best practice for corporate offices globally.

3.
Sci Rep ; 6: 27926, 2016 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-27297474

RESUMO

A non-trivial temperature evolution of superconductivity including a temperature-induced phase transition between two superconducting phases or even a time-reversal symmetry breaking order parameter is in principle expected in multiband superconductors such as iron-pnictides. Here we present scanning tunnelling spectroscopy data of LiFeAs which reveal two distinct superconducting phases: at = 18 K a partial superconducting gap opens, evidenced by subtle, yet clear features in the tunnelling spectra, i.e. particle-hole symmetric coherence peak and dip-hump structures. At Tc = 16 K, these features substantiate dramatically and become characteristic of full superconductivity. Remarkably, the distance between the dip-hump structures and the coherence peaks remains practically constant in the whole temperature regimeT ≤ . This rules out the connection of the dip-hump structures to an antiferromagnetic spin resonance.

4.
Rev Sci Instrum ; 85(1): 013706, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24517774

RESUMO

We present the design, setup, and operation of a new dip-stick scanning tunneling microscope. Its special design allows measurements in the temperature range from 4.7 K up to room temperature, where cryogenic vacuum conditions are maintained during the measurement. The system fits into every (4)He vessel with a bore of 50 mm, e.g., a transport dewar or a magnet bath cryostat. The microscope is equipped with a cleaving mechanism for cleaving single crystals in the whole temperature range and under cryogenic vacuum conditions. For the tip approach, a capacitive automated coarse approach is implemented. We present test measurements on the charge density wave system 2H-NbSe2 and the superconductor LiFeAs which demonstrate scanning tunneling microscopy and spectroscopy data acquisition with high stability, high spatial resolution at variable temperatures and in high magnetic fields.

5.
Ind Health ; 51(1): 113-22, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23411761

RESUMO

Extreme climatic heat is a major health concern among workers in different occupational pursuits. People in the regions of western India confront frequent heat emergencies, with great risk of mortality and morbidity. Taking account of informal occupational groups (foundry and sheet metal, FSM, N=587; ceramic and pottery, CP, N=426; stone quarry, SQ, N=934) in different seasons, the study examined the body temperature profiling as indicator of vulnerability to environmental warmth. About 3/4th of 1947 workers had habitual exposure at 30.1-35.5°C WBGT and ~10% of them were exposed to 38.2-41.6°C WBGT. The responses of FSM, CP and SQ workers indicated prevailing high heat load during summer and post-monsoon months. Local skin temperatures (T(sk)) varied significantly in different seasons, with consistently high level in summer, followed by post-monsoon and winter months. The mean difference of T(cr) and T(sk) was ~5.2°C up to 26.7°C WBGT, and ~2.5°C beyond 30°C WBGT. Nearly 90% of the workers had T(cr) within 38°C, suggesting their self-adjustment strategy in pacing work and regulating T(cr). In extreme heat, the limit of peripheral adjustability (35-36°C T(sk)) and the narrowing down of the difference between T(cr) and T(sk) might indicate the limit of one's ability to withstand heat exposure.


Assuntos
Temperatura Corporal , Mudança Climática , Transtornos de Estresse por Calor/etiologia , Doenças Profissionais/etiologia , Exposição Ocupacional/efeitos adversos , Ocupações , Adulto , Feminino , Transtornos de Estresse por Calor/epidemiologia , Humanos , Índia/epidemiologia , Masculino , Doenças Profissionais/epidemiologia , Medição de Risco , Fatores de Risco , Estações do Ano , Termografia/métodos
6.
Ind Health ; 48(3): 339-48, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20562510

RESUMO

A study was undertaken to identify the work stressors among male and female weavers (N=516) in powerloom and handloom and examine the association of work stressors with the prevalence of work related musculo-skeletal disorders (MSDs). Physical and psychosocial stresses of work, job diagnostics, hazards of workplace, working environment and MSDs prevalence were assessed. There is high prevalence of MSDs among weavers. Female weavers in powerloom and handloom were more prone to developing MSDs in upper back (OR 1.8; p<0.05 and OR 2.1; p<0.01) and lower back (OR 1.9; p<0.05 and OR 1.8; p<0.05). Male weavers were more prone to developing pain in the knee (OR 2.9; p<0.001), and hand (OR 2.2; p<0.05). Multivariate analysis indicated that job duration >10 yr (OR 3.7, p<0.05), manual material handling (OR 3, p<0.05), and poor machinery safety (OR 11, p<0.05), contributed to occurrence of MSDs amongst powerloom weavers. Among the handloom weavers, age >25 yr (OR 3.2, p<0.05), poor machinery design (OR 2.2, p<0.01), mental overload (OR 5.7, p<0.001), skill requirement to perform jobs (OR 20.7, p<0.05) had significant influence in the occurrence of pain. Gender differences exist in the prevalence of MSDs and the perception of work and psycho-social stresses among the weavers.


Assuntos
Doenças Musculoesqueléticas/epidemiologia , Doenças Profissionais/epidemiologia , Fatores Sexuais , Estresse Fisiológico , Estresse Psicológico/epidemiologia , Indústria Têxtil/estatística & dados numéricos , Adulto , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Dor/epidemiologia , Prevalência , Fatores de Risco , Inquéritos e Questionários , Fatores de Tempo
8.
Appl Ergon ; 40(2): 286-91, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18508029

RESUMO

The effects of forearm and wrist supports on the upper extremity postures in computer keying tasks and associated EMG activity of arm and back muscles were examined (N = 8). Four positions were forearms unsupported (floating) and supported, wrists supported by bead packed (WR1) and gel-filled (WR2) wrist rest. The right and left elbow extensions were 65 degrees and 68 degrees , respectively, in unsupported forearms. Bilateral elbow extension increased with the forearm/wrist supports and mostly, the elbow was maintained at around 90 degrees or greater. The wrist extension decreased with forearm/wrist supports over the unsupported condition. The forearm support significantly reduced the activity of forearm extensor digitorum, i.e., right (F((1, 47)) = 12.19, p < 0.01) and left (F((1, 47)) = 5.38, p < 0.05) and upper trapezius muscles over the floating posture. Wrist rests, however, increased load on the upper trapezius; the activities of flexor digitorum superficialis and erector spinae were close to the resting EMG activity for both forearm and/or wrist support. The type of wrist rests was a concern and this study indicated that the gel filled wrist rest was advantageous in reducing the forearm muscle load, in comparison to the bead packed cushions.


Assuntos
Sistemas Homem-Máquina , Músculo Esquelético/fisiologia , Postura/fisiologia , Análise e Desempenho de Tarefas , Braço , Dorso , Fenômenos Biomecânicos , Terminais de Computador , Eletromiografia , Humanos , Masculino , Doenças Profissionais/fisiopatologia , Punho , Adulto Jovem
9.
Indian J Med Res ; 117: 260-9, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-14748472

RESUMO

BACKGROUND & OBJECTIVES: Data on the physical dimension of the hand of Indian women are scanty. This information is necessary to ascertain human-machine compatibility in the design of manual systems for the bare and gloved hand, such as design and sizing of hand tools, controls, knobs and other applications in different kinds of precision and power grips. The present study was undertaken to generate hand anthropometric data of 95 women, working in informal industries (beedi, agarbatti and garment making). METHODS: Fifty one hand measurements of the right hand (lengths, breadths, circumferences, depths, spreads and clearances of hand and fingers) were taken, using anthropometric sliding and spreading calipers, measuring tape and handgrip strength dynamometer. The data were statistically analyzed to determine the normality of data and the percentile values of different hand dimensions, and simple and multiple regression analysis were done to determine better predictors of hand length and grip strength. RESULTS: The hand breadths, circumferences and depths were approximately normally distributed, with some deviation in case of the finger lengths. Hand length was significantly correlated with the fist, wrist and finger circumferences. The fist and wrist circumferences, in combination, were better predictors of hand length. The hand lengths, breadths and depths, including finger joints of the Indian women studied were smaller than those of American, British and West Indian women. The hand circumferences of the Indian women were also smaller than the American women. Grip strengths of Indian women (20.36 +/- 3.24 kg) were less than those of American, British and West Indian women. Grip strength was found to be statistically significant with hand dimensions, such as hand height perpendicular to wrist crease (digit 5), proximal interphalangeal joint breadth (digit 3) and hand spread across wedge 1. INTERPRETATION & CONCLUSION: The women who are forced to frequently use cutters, strippers and other tools, which are not optimally designed to their hand dimensions and strength range, might have higher prevalence of clinical symptoms and disorders of the hand. In view of the human hand-tool interface requirements, the present data on Indian women would be useful for ergo-design applications of hand tools and devices.


Assuntos
Mãos/anatomia & histologia , Adolescente , Adulto , Antropometria , Ergonomia , Feminino , Humanos , Índia , Pessoa de Meia-Idade , Saúde Ocupacional
10.
J Hum Ergol (Tokyo) ; 30(1-2): 161-6, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14564876

RESUMO

The study examined the risks of heat induced workplace accidents (textile industry, N = 4125) and the heat tolerability of the rotating day (morning and afternoon, N = 16) and permanent night shift workers (N = 13) in hot-dry and hot-humid environment (34 to 49 degrees C, 50-80% RH; 31 to 42 degrees C ET, Basic). Accident prevalence was significantly high in the summer months (May-June) when the ambient temperature ranged between 42 and 48 degrees C (hot-dry). The influence of hot climate in accident causation was evident from the shift-wise variations in the occurrence of accidents. The longitudinal study showed that the night workers were more vulnerable and less tolerant to heat, the tolerance time being less by about 15% (31 degrees C ET) to 40% (39 degrees C ET), compared to the rotating day workers. The relationship of the segmental and compartmental temperatures (segmental triggering response) played a critical role in heat dissipation/accumulation mechanism, and reflected in the heat tolerability of the day and night workers.


Assuntos
Acidentes de Trabalho/estatística & dados numéricos , Países em Desenvolvimento , Transtornos de Estresse por Calor/epidemiologia , Clima Tropical , Tolerância ao Trabalho Programado , Adulto , Ritmo Circadiano , Estudos Transversais , Feminino , Humanos , Índia/epidemiologia , Estudos Longitudinais , Masculino , Risco , Estações do Ano , Indústria Têxtil
11.
Ergonomics ; 41(2): 179-87, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9494430

RESUMO

The efficacy of a water-cooled jacket for auxiliary body cooling was examined under a simulated hot environment. The personal garment comprised of a water re-circulating three-layered vest of cotton fabric lined with 2 mm diameter latex tubing and inter-spaced coating of rubberized solution. Four subjects wearing the water-cooled jacket were tested in the environment chamber (30, 35 and 40 degrees C DB, 50-60% RH, air velocity 0.3, 0.6 and 0.9 m/s, with corresponding average effective temperature of 26 +/- 2.3, 33 +/- 1.1 and 36 +/- 1.5 degrees C). The inlet water temperature was maintained at 10-12 degrees C, with flow rates of 2.6 +/- 0.3, 4.3 +/- 0.3 and 5.1 +/- 0.3 l/h). At 30 degrees C DB, variation in water flow had marginal effect on microclimate, while at higher temperatures (35 and 40 degrees C DB), the re-circulating cooled water had noticeable effects in lowering microclimate, trunk and other skin temperatures, and maintaining the body core within 36.7 +/- 0.2 to 37.5 +/- 0.2 degrees C, over 2 h exposure at 35 and 40 degrees C DB. The observation indicates that the water-cooled jacket provided auxiliary cooling to maintain comfortable microclimate, skin and body core temperatures. This enabled subjects to sustain comfortable heat balance over 2 h heat exposure without any noticeable heat strain.


Assuntos
Temperatura Baixa , Transtornos de Estresse por Calor/prevenção & controle , Látex , Roupa de Proteção/normas , Água , Adulto , Temperatura Corporal , Ergonomia , Humanos , Masculino , Temperatura
12.
Indian J Med Res ; 105: 226-34, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9183079

RESUMO

The heat tolerance of 11 male volunteers were examined under seven climatic conditions in a climatic chamber. The conditions were 38 to 49 degrees C dry bulb temperature and 45 to 80 per cent relative humidity, i.e., 32.3 to 40 degrees C effective temperature-basic [ET(B)]. The ET(B) values were equated to other heat stress indices, e.g., WBGT (Wet-bulb Globe Temperature Index) and Oxford Index. The subjects did ergometric work at an intensity of 60 per cent VO2max. The exposure durations were decided by the cardiorespiratory, body temperature and sweating responses. Of the climatic conditions studied, at 35.4, 38, 39 and 40 degrees C ET(B), the body core temperature (Tcr) reached over 39 degrees C and heart rates attained 172 to 182 beats/min, which were taken as the tolerance limit. The total oxygen demand significantly varied with the increase in environmental warmth, i.e., increase or decrease of one litre of oxygen demand was equivalent to one minute change in tolerance time. The volunteers were not susceptible to heat; only in extreme hot situations beyond 35.4 degrees C ET(B), were unacceptable levels of physiological and psychophysical reactions seen. The study suggests the acceptable and tolerable limits for human exposure in heat: (i) acceptable at 38 to 38.2 degrees C Tcr for a tolerance time of 80 to 85 min; and (ii) the tolerable limit of short duration (40-45 min) at 39 degrees C Tcr that corresponded to 31.5 and 36.5 degrees C ET(B).


Assuntos
Regulação da Temperatura Corporal , Transtornos de Estresse por Calor/fisiopatologia , Consumo de Oxigênio , Adolescente , Adulto , Teste de Esforço , Humanos , Masculino , Distribuição Aleatória , Fatores de Tempo , Clima Tropical
13.
J Hum Ergol (Tokyo) ; 25(2): 105-13, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9735591

RESUMO

The working capacity of young, healthy, unacclimatized men (N = 11) was studied under long-duration (8 to 9 days) exposure to combined work and heat (dry and humid). The dry (Gr A, N = 5) and humid (Gr B, N = 6) groups were exposed to 41.3 +/- 0.6 degrees C DB, 40-50% RH and 39.2 +/- 0.6 degrees C DB, 70-80% RH, respectively, for all days of exposure. The experimental protocol was divided into: (i) direct determination of maximal oxygen uptake (VO2max) by stepped increases in bicycle ergometry everyday in the morning in the initial hours before exposure to heat, after which the recovery process of oxygen debt contraction was examined; and (ii) exposure to heat in a climatic chamber for 2 h where the subjects performed two spells of ergometric work (10 to 12 min each) at a relative intensity of 50 +/- 12 to 69 +/- 11% VO2max. The average heat exposure time for Gr A was higher (108 +/- 12 min) as compared to Gr B (95 +/- 10 min), but Gr B sustained a high heat load as reflected from the high deep-body temperature maintained during the exposure. The high body temperature load of Gr B had a significant effect on the cardiorespiratory capacity, indicating an upward trend in VO2max. This was statistically significant (p < 0.05) for the first four days of exposure. Subjects of Gr B had a relatively higher working capacity compared to those in Gr A on all days. The VO2max and analysis of the fractions of oxygen debt contraction (fast and slow component) indicated that the subjects showed a better training/heat acclimatization effect under hot, humid conditions.


Assuntos
Temperatura Alta/efeitos adversos , Esforço Físico/fisiologia , Clima Tropical/efeitos adversos , Avaliação da Capacidade de Trabalho , Adulto , Humanos , Índia , Masculino , Oxigênio/metabolismo
14.
J Neuroendocrinol ; 7(7): 567-76, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7496397

RESUMO

Circulating concentrations of gonadal steroid hormones and reproductive behavior in female vertebrates vary as a function of ovarian state. Steroids secreted by the ovary, specifically estrogen and progesterone, influence the expression of behaviors associated with reproduction by intracellular sex steroid receptors located in specific regions of the brain. Using in situ hybridization, we analyzed estrogen receptor and progesterone receptor messenger RNA expression in several brain regions of ovariectomized, vitellogenic, and postovulatory individuals from two species of whiptail lizards (Cnemidophorus uniparens and C. inornatus). Although these species are genetically very similar, they differ in two aspects of their reproductive biology: (i) the unisexual C. uniparens alternate between expressing female-typical and male-like pseudosexual behaviors while female C. inornatus normally express only female receptive behavior, and (ii) circulating estradiol concentrations in reproductively active female C. uniparens are approximately five-fold lower than in reproductively active female C. inornatus. We found that the regulation of sex steroid receptor gene expression was region specific, with receptor-mRNA expression being increased, unchanged, or decreased during vitellogenesis depending on the area. Furthermore, several species differences in the amount of sex steroid receptor-mRNA were found that may be relevant to the species differences in circulating estrogen concentrations and sexual behavior.


Assuntos
Encéfalo/metabolismo , Lagartos/metabolismo , RNA Mensageiro/biossíntese , Receptores de Estrogênio/genética , Receptores de Progesterona/genética , Caracteres Sexuais , Animais , Evolução Biológica , Feminino , Hibridização In Situ , Lagartos/anatomia & histologia , Ovário/fisiologia , Partenogênese , Comportamento Sexual Animal/fisiologia , Especificidade da Espécie
15.
Neuroendocrinology ; 61(6): 680-6, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7659192

RESUMO

Cnemidophorus uniparens is a unisexual species of whiptail lizard of hybrid origin whereas C. inornatus is a sexual species and the maternal ancestor of C. uniparens. Together they represent an excellent model system for investigating the evolution of hormone-brain-behavior relationships. Normal circulating estradiol (E) concentrations in C. uniparens are approximately 5-fold lower than those of female C. inornatus in a similar reproductive state. Experiments were performed to determine whether (i) C. uniparens is more sensitive to E, and (ii) whether the difference in sensitivity is correlated with differences in estrogen receptor (ER)-mRNA expression in the brain. Dose-response curves reveal that ovariectomized C. uniparens are more responsive than ovariectomized C. inornatus to exogenous estradiol 17 beta-benzoate (EB). EB is more effective in C. uniparens at inducing receptive behavior and progesterone receptor (PR) gene expression in the ventromedial nucleus of the hypothalamus (VMH). In situ hybridization analysis of ER-mRNA expression revealed no species differences in ER-mRNA content in the VMH of ovariectomized animals. Treatment of ovariectomized animals with EB resulted in a greater induction of ER-mRNA expression in the VMH of C. uniparens compared to C. inornatus. These results indicate that the differences in behavioral sensitivity to E lie in the estrogen target neurons in the brain region controlling receptive behavior, the VMH, and that the difference in sensitivity cannot be explained by species differences in the basal rate of ER gene expression.


Assuntos
Comportamento Animal/efeitos dos fármacos , Estrogênios/farmacologia , Lagartos/fisiologia , Neurônios/efeitos dos fármacos , RNA Mensageiro/biossíntese , Receptores de Superfície Celular/biossíntese , Animais , Relação Dose-Resposta a Droga , Estradiol/farmacologia , Feminino , Hibridização In Situ , Neurônios/metabolismo , Ovariectomia , Especificidade da Espécie , Núcleo Hipotalâmico Ventromedial/efeitos dos fármacos , Núcleo Hipotalâmico Ventromedial/metabolismo
16.
J Neuroendocrinol ; 7(2): 119-25, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7767324

RESUMO

Receptive behavior in females vertebrates is controlled by hormones, principally estrogen, secreted by the ovary. Estrogen influences behavior by interacting with a specific estrogen binding protein, or receptor, located in target cells in certain hypothalamic nuclei. To better understand the molecular mechanisms involved in the control of receptive behavior in whiptail lizards, we investigated the effects of exogenous estrogen on the regulation of estrogen receptor and progesterone receptor expression in several regions of the brains of Cnemidophorus uniparens. First we determined a dosage of 17 beta-estradiol 3-benzoate (0.5 micrograms) which reliably induced receptive behavior in ovariectomized C. uniparens. Then using in situ hybridization, we examined the effects of that dosage on the expression of estrogen receptor and progesterone receptor mRNA in the brain 24 h after injection. Estrogen treatment resulted in a significant up-regulation of estrogen receptor mRNA expression in the ventromedial nucleus of the hypothalamus and torus semicircularis, down-regulation of estrogen receptor mRNA expression in the lateral septum, and no change in the periventricular nuclei of the hypothalamus, the periventricular nucleus of the preoptic area, and the dorsal hypothalamus. The same dosage resulted in increased progesterone receptor mRNA expression in the ventromedial nucleus of the hypothalamus and the periventricular nucleus of the preoptic area; no significant changes in progesterone receptor mRNA expression were observed in the periventricular nuclei of the hypothalamus or the torus semicircularis, although the differences in progesterone receptor expression in the torus semicircularis approached statistical significance.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Encéfalo/efeitos dos fármacos , Estradiol/farmacologia , Lagartos/metabolismo , RNA Mensageiro/biossíntese , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Progesterona/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Feminino , Hibridização In Situ , Ovariectomia , Ovário/fisiologia , Receptores de Estrogênio/genética , Receptores de Progesterona/genética
17.
J Hum Ergol (Tokyo) ; 22(2): 151-61, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7963481

RESUMO

The skin temperature is fundamental to heat exchange between the human body and the environment. The convective and evaporative heat exchanges depend on the temperature gradient and the extent of air flow over the skin surface. An attempt was made to study the topographical differences in skin temperature (Tsk) under varied levels of air flow and to examine the possible body temperature regulatory mechanism. Five volunteers were examined in a climatic chamber at 30 and 36 degrees C DB at 55-60% RH (ambient vapour pressure of 2.58 and 3.53 kPa and air flow of 0.6, 1.4, 1.9, 2.1 m/s). The deep body temperature (Tc) and local Tsk were recorded at 5-min intervals during 10 min pre-exposure, 30 min exposure to heat and 15 min recovery period after air flow was withdrawn. The time taken to attain at the lowest Tsk in different air speeds varied from 30 to 45 min. The highest drop in Tsk (2.4 degrees C) was recorded for forehead at 30 degrees C DB and significant skin cooling was achieved at an air flow of 0.6 m/s for most body regions. The overall drop in local Tsk was more greater at a higher ambient temperature (36 degrees C) and the changes were significantly different (p < 0.05) to those recorded at the preexposure level. There was a consistent drop in Tsk with time, while no definite pattern of drop was noted with the magnitude of air flow. The Tc increased significantly with the continued air flow and following withdrawal of air flow the Tc tended to drop, suggesting heat gain by the body with a consequent increase in Tc.


Assuntos
Movimentos do Ar , Temperatura Cutânea/fisiologia , Adulto , Humanos , Masculino , Fatores de Tempo
18.
Am Ind Hyg Assoc J ; 53(12): 751-6, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1471596

RESUMO

Six women were exposed to nine environmental conditions, ranging from 26.0 to 35.8 degrees C effective temperature (ET), in a climatic chamber. They were involved in manipulative work in a seated position for a duration of 3 hr. The O2 uptake, heart rate, deep body (Tc) and skin temperature (Tsk), sweat loss, and perception of thermal comfort were noted. The O2 uptake increased with the time of exposure at different heat levels. The work energy demand, which was 19% of VO2max at 26 degree C ET, increased to 35% of VO2max at 35.8 degrees C ET. However, the work output declined with the increase in ET. Thus, the elevated metabolic demands were the results of the thermal stimuli. The Tsk was greatly influenced by the environmental heat; the Tc changes were gradual. The highest mean Tsk attained was 37.3 degrees C at 33.8 degrees C ET when the gradient of Tc-Tsk was only 0.5 degrees C. The rate of change in mean Tsk for 31.6 to 33.8 degrees C ET was much faster compared to the range between 26.0 and 31.6 degrees C ET. From 32.1 degrees C ET onward the Tc and heart rates rose rapidly, while the sweating rate tended to fall, indicating some hindrance for evaporative cooling. Also, thermal sensations were noted as extremely hot for the conditions 32.1 to 35.8 degrees C ET with the increase in exposure duration.


Assuntos
Temperatura Alta/efeitos adversos , Estresse Fisiológico/fisiopatologia , Trabalho , Adulto , Regulação da Temperatura Corporal , Exposição Ambiental , Feminino , Frequência Cardíaca , Humanos , Consumo de Oxigênio , Temperatura Cutânea , Sudorese
19.
J Hum Ergol (Tokyo) ; 21(1): 47-55, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1491171

RESUMO

The study examined the work stresses of 107 women who were engaged in sewing machine operation in small garment manufacturing units. Of the three types of sewing machines (motor-operated, full and half shuttle foot-operated), 74% of the machines were foot-operated, where throttle action of the lower limb is required to move the shuttle of the machine. The motor-operated machines were faster than the foot-operated machines. The short cycle sewing work involves repetitive action of hand and feet. The women had to maintain a constant seated position on a stool without backrest and the body inclined forward. Long-term sewing work had a cumulative load on the musculo-skeletal structures, including the vertebral column and reflected in the form of high prevalence of discomfort and pain in different body parts. About 68% of the women complained of back pain, among whom 35% reported a persistent low back pain. Common sewing work accident is piercing of the needle through the fingers, particularly the right forefingers. Unsatisfactory man-machine incompatibility, work posture and fatigue, improper coordination of eye, leg and hand are the major problems of the operators. The design mis-match of the work place may be significantly improved by taking women's anthropometric dimensions in modifying the workplace, i.e. the seat surface, seat height, work height, backrest, etc.


Assuntos
Saúde Ocupacional , Estresse Mecânico , Indústria Têxtil , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Postura , Fatores de Tempo
20.
Appl Ergon ; 22(3): 185-8, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15676814

RESUMO

This study examines the influence of different modes of load holding on the isometric strength exertion and endurance capacity. Six healthy males underwent longitudinal testing with the trunk, knee and elbow in 10 different (straight and bent) postures. The load heights (LH) of 320, 440, 850 and 1250 mm from the floor level with subject-load-distance (S-L-D) of 120 and 320 mm were used. It was noted that the level and duration of force exertion were higher when the load was placed closer to the body. The endurance times were consistently high with the increase in LH, highest being recorded in Position 9 - i e, with the load placed at the shoulder level and S-L-D of 120 mm. As evident from MVC and endurance times, the back straight/knee bent postures may not be preferred to back bent postures.

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