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1.
J Phys Chem Lett ; 15(4): 895-902, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38241169

RESUMEN

Cyanogen NCCN and cyanoacetylene HCCCN are isoelectronic molecules, and as such, they have many similar properties. We focus on the bond cleavage in these induced by the dissociative electron attachment. In both molecules, resonant electron attachment produces CN- with very similar energy dependence. We investigate the very different dissociation dynamics, in each of the two molecules, revealed by velocity map imaging of this common fragment. Different dynamics are manifested both in the excess energy partitioning and in the angular distributions of fragments. Based on the comparison with electron energy loss spectra, which provide information about possible parent states of the resonances (both optically allowed and forbidden excited states of the neutral target), we ascribe the observed effect to the distortion of the nuclear frame during the formation of core-excited resonance in cyanoacetylene. The proposed mechanism also explains a puzzling difference in the magnitude of the CN- cross section in the two molecules which has been so far unexplained.

2.
J Dent Res ; 102(10): 1162-1171, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37449307

RESUMEN

Teeth consist of 3 mineralized tissues: enamel, dentin, and cementum. Tooth malformation, the most common craniofacial anomaly, arises from complex genetic and environmental factors affecting enamel structure, size, shape, and tooth eruption. Hyaluronic acid (HA), a primary extracellular matrix component, contributes to structural and physiological functions in periodontal tissue. Transmembrane protein 2 (TMEM2), a novel cell surface hyaluronidase, has been shown to play a critical role during embryogenesis. In this study, we demonstrate Tmem2 messenger RNA expression in inner enamel epithelium and presecretory, secretory, and mature ameloblasts. Tmem2 knock-in reporter mice reveal TMEM2 protein localization at the apical and basal ends of secretory ameloblasts. Micro-computed tomography analysis of epithelial-specific Tmem2 conditional knockout (Tmem2-CKO) mice shows a significant reduction in enamel layer thickness and severe enamel deficiency. Enamel matrix protein expression was remarkably downregulated in Tmem2-CKO mice. Scanning electron microscopy of enamel from Tmem2-CKO mice revealed an irregular enamel prism structure, while the microhardness and density of enamel were significantly reduced, indicating impaired ameloblast differentiation and enamel matrix mineralization. Histological evaluation indicated weak adhesion between cells and the basement membrane in Tmem2-CKO mice. The reduced and irregular expressions of vinculin and integrin ß1 suggest that Tmem2 deficiency attenuated focal adhesion formation. In addition, abnormal HA accumulation in the ameloblast layer and weak claudin 1 immunoreactivity in Tmem2-CKO mice indicate impaired tight junction gate function. Irregular actin filament assembly was also observed at the apical and basal ends of secretory ameloblasts. Last, we demonstrated that Tmem2-deficient mHAT9d mouse ameloblasts exhibit defective adhesion to HA-containing substrates in vitro. Collectively, our data highlight the importance of TMEM2 in adhesion to HA-rich extracellular matrix, cell-to-cell adhesion, ameloblast differentiation, and enamel matrix mineralization.


Asunto(s)
Hipoplasia del Esmalte Dental , Ratones , Animales , Hipoplasia del Esmalte Dental/genética , Microtomografía por Rayos X , Esmalte Dental/metabolismo , Ameloblastos/metabolismo , Amelogénesis/genética , Ratones Noqueados , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo
3.
J Phys Chem Lett ; 13(48): 11136-11142, 2022 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-36441975

RESUMEN

We experimentally show that N-H bond cleavage in the pyrrole molecule following resonant electron attachment is allowed and controlled by the motion of the atoms which are not dissociating, namely, of the carbon-attached hydrogen atoms. We use this fact to steer the efficiency of this bond cleavage. In order to interpret the experimental findings, we have developed a method for locating all resonant and virtual states of an electron-molecule system in the complex plane, based on all-electron R-matrix scattering calculations. Mapping these as a function of molecular geometry allows us to separate two contributing dissociation mechanisms: a π* resonance formation inducing strong bending deformations and a nonresonant σ* mechanism originating in a virtual state. The coupling between the two mechanisms is enabled by the out-of-plane motion of the C-H bonds, and we show that it must happen on an ultrafast (few fs) time scale.

4.
J Indian Prosthodont Soc ; 20(3): 326-330, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33223704

RESUMEN

Surgical resection of the mandible due to the presence of benign or malignant tumor commonly results in the deviation of the remaining mandible toward the defective side. Based on the location and extent (mandible), various surgical approaches such as marginal, segmental, and hemi or subtotal or total mandibulectomy can be executed. The restoration of normal form, function, and esthetic is often challenging in the prosthetic rehabilitation of patients with hemimandibulectomy. A 36-year-old male patient reported with a chief complaint of difficulty in eating and speech. Past dental history of the patient revealed ameloblastoma of the left mandibular alveolus, which was surgically operated 6 years back with a wide resection of the tumor with left-sided hemimandibulectomy without disarticulation and reconstruction with an osteocutaneous free fibula flap (from the right leg) fixed with a screw plate system. This case report suggests that the rehabilitation of surgically resected patients using tilted implant technique can reach a desirable prosthetic outcome. This clinical report describes prosthetic management (implant-supported fixed prosthesis) of a hemimandibulectomy patient using tilted implants and screw-retained prosthetic solutions using multiunit abutments. It improves speech, masticatory efficiency, and esthetics without any further deviation of the mandible with a 3-year follow-up.

5.
J Chem Phys ; 152(24): 244304, 2020 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-32610971

RESUMEN

We probe the transient anion states (resonances) in the dielectric gas C4F7N by the electron energy loss spectroscopy and the dissociative electron attachment spectroscopy. The vibrationally inelastic electron scattering leads to two excitation types. The first is the excitation of specific vibrational modes that are assigned with the help of an infrared spectrum of this molecule and quantum chemistry calculations. In the second type of vibrational excitation, the excess energy is randomized via internal vibrational redistribution in the temporary anion, and the electrons are emitted statistically. The electron attachment proceeds in three different regimes. The first is the formation of the parent C4F7N- anion at energies close to 0 eV. The second is a statistical evaporation of the F-atom, leading to the defluorinated anion C4F6N-. Finally, the third is dissociative electron attachment proceeding via the formation of several resonances and leading to a number of fragments. The present data explain the puzzling recent results of the pulsed-Townsend experiments with this gas.

6.
Theriogenology ; 141: 161-167, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31542519

RESUMEN

To test our hypothesis that antisperm antibodies (ASA) might alter sperm phenotypic attributes thus leading to sub-fertility/infertility in bulls, ASA were generated in crossbred male calves by immunizing with sperm two times. Cryopreserved spermatozoa from crossbred bulls (n = 24) with different field fertility ratings were incubated with ASA and different patterns of ASA immunolocalization were studied. In addition, sperm membrane integrity, acrosomal integrity and cryo-capacitation status were also assessed. Immunolocalization of sperm antigens using antisperm antibody revealed three major patterns (Acrosomal-AR, apical-AP and, acrosome and tail-AT). The proportion of ASA reactive spermatozoa was significantly (P < 0.05) higher in low- and medium-fertile bulls compared to high-fertile bulls. Among the three patterns, the proportion of spermatozoa with AR pattern was significantly (P < 0.05) higher in low- and medium-fertile bulls compared to high-fertile bulls. The proportion of membrane and acrosome intact spermatozoa was significantly (P < 0.05) higher in high-fertile bulls compared to medium- and low-fertile bulls. There were no significant differences in the proportion of cryo-capacitated spermatozoa among high-, medium- and low-fertile bulls. The relationship between ASA reactive spermatozoa and conception rates (CR) of bulls was highly (P < 0.01) significant and negative. Similarly, AR and AT pattern were also significantly (P < 0.01) and negatively related to CR of bulls. The reactivity of spermatozoa with ASA was also significantly (P < 0.01) and negatively related to the membrane and acrosome integrity of spermatozoa. It was concluded that the proportion of spermatozoa responding to ASA was higher in low-compared to high-fertile bulls and ASA localization in sperm acrosomal area was negatively related to sperm membrane and acrosomal integrity and bull fertility.


Asunto(s)
Anticuerpos/fisiología , Especificidad de Anticuerpos/fisiología , Bovinos/fisiología , Fertilidad/fisiología , Espermatozoides/fisiología , Animales , Antígenos/fisiología , Bovinos/inmunología , Masculino , Análisis de Semen
7.
J Appl Microbiol ; 129(2): 186-198, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31858682

RESUMEN

In an agro-ecosystem, industrially produced nitrogenous fertilizers are the principal sources of nitrogen for plant growth; unfortunately these also serve as the leading sources of pollution. Hence, it becomes imperative to find pollution-free methods of providing nitrogen to crop plants. A diverse group of free-living, plant associative and symbiotic prokaryotes are able to perform biological nitrogen fixation (BNF). BNF is a two component process involving the nitrogen fixing diazotrophs and the host plant. Symbiotic nitrogen fixation is most efficient as it can fix nitrogen inside the nodule formed on the roots of the plant; delivering nitrogen directly to the host. However, most of the important crop plants are nonleguminous and are unable to form symbiotic associations. In this context, the plant associative and endophytic diazotrophs assume importance. BNF in nonlegumes can be encouraged either through the transfer of BNF traits from legumes or by elevating the nitrogen fixing capacity of the associative and endophytic diazotrophs. In this review we discuss mainly the microbiological strategies which may be used in nonleguminous crops for enhancement of BNF.


Asunto(s)
Productos Agrícolas/microbiología , Endófitos/metabolismo , Fijación del Nitrógeno , Fabaceae/microbiología , Nódulos de las Raíces de las Plantas/microbiología , Simbiosis
8.
J Contemp Dent Pract ; 20(6): 754-763, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-31358722

RESUMEN

AIM: A severely atrophied maxilla presents serious limitations for conventional implant placement and the reconstruction of which requires extensive surgical treatments. This original article presents an overview of this evidence-based technique used for maxillary rehabilitation. BACKGROUND: Growing patients' needs to regain proper oral function with limited surgical effort presents a challenge to the surgeon for implant placement in harmony with the planned prosthesis. Different techniques and protocols have been put forward through the ages to improve implant survival, osseointegration, and quality of life. A new technique-Tall Tilted Pin Hole Immediate Loading (TTPHIL-ALL TILT™ technique)-utilizes angulated long bicortical tapered implants placed in a flapless way in immediate loading with screw-retained prosthetic solutions. TECHNIQUE: TTPHIL-ALL TILT™ technique involves flapless subcrestal bicortical placement of a total of six tall threaded tilted implants engaging the nasal cortex and the pterygoid pillars, rigidly splinted maintaining adequate anteroposterior spread, achieving proper primary stability, fit for immediate loading. Screw-retained prosthetic solutions are provided with the elimination of distal cantilever. CONCLUSION: The TTPHIL-ALL TILT™ technique can facilitate surgical rehabilitation of patients with maxillary resorption, as an alternative to other graft less and grafting procedures. CLINICAL SIGNIFICANCE: TTPHIL-ALL TILT™ technique provides a graftless solution for the challenging resorbed maxillary edentulous ridges. By following this protocol, primary stability is achieved which gives way for immediate loading satisfying the patient's functional and aesthetic needs.


Asunto(s)
Implantes Dentales , Carga Inmediata del Implante Dental , Arcada Edéntula , Implantación Dental Endoósea , Prótesis Dental de Soporte Implantado , Fracaso de la Restauración Dental , Estética Dental , Estudios de Seguimiento , Humanos , Maxilar , Calidad de Vida , Resultado del Tratamiento
9.
Cancer Radiother ; 22(2): 163-166, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29615371

RESUMEN

PURPOSE: The main objective of our study is to evaluate response and toxicity profile in patients receiving external beam radiotherapy with concurrent chemotherapy followed by intraluminal brachytherapy boost for a carcinoma of the oesophagus. MATERIAL AND METHODS: Twenty patients with biopsy-proven carcinoma of the oesophagus received external beam radiotherapy (50Gy in 25 fractions) with concurrent chemotherapy (cisplatin: 40mg/m2). After a gap of two to three weeks, intraluminal brachytherapy (10Gy in two fractions each 1 week apart by a high dose rate 60Co source) was given. Response was evaluated at 1 month and at 1 year of completion of treatment. In addition, acute and chronic toxicity was evaluated at 1 month and 6 months of treatment. RESULTS: Complete response were seen in 80% of patients and partial response in 20% at 1 month. Moreover, there were 65% complete response, 10% local recurrences, 15% patients showed local control with distant metastasis and 10% patients died at 1 year. Grade 1, grade 2 and grade 3 oesophagitis were seen in 10%, 70% and 20% of patients respectively. Stricture was seen in 40% of patients and fistula in 10% of patients. There was no spinal cord, cardiac and nephrotoxicity found. CONCLUSIONS: With the concept that high tumoricidal dose for adequate tumor control achieved by intraluminal brachytherapy as a mean of dose escalation, while sparing surrounding normal tissue and potentially improving therapeutic ratio, external beam radiotherapy followed by intraluminal brachytherapy could be a better choice for oesophagus carcinoma.


Asunto(s)
Braquiterapia/métodos , Carcinoma/terapia , Quimioradioterapia , Neoplasias Esofágicas/terapia , Radioterapia Adyuvante , Carcinoma/mortalidad , Carcinoma/patología , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/patología , Estenosis Esofágica/etiología , Esofagitis/clasificación , Esofagitis/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estudios Prospectivos , Dosificación Radioterapéutica
10.
Indian J Occup Environ Med ; 21(2): 77-83, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29540968

RESUMEN

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.

11.
Indian J Occup Environ Med ; 21(1): 18-22, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29391743

RESUMEN

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.

12.
Cancer Radiother ; 20(5): 370-6, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27368915

RESUMEN

PURPOSE: The use of intensity-modulated radiotherapy (IMRT) to treat cervix carcinoma has increased, however prospective randomized trials are still lacking. AIM: To compare the dosimetric parameters and associated acute toxicity in patients with cervix carcinoma treated with three-dimensional (3D) conformal radiotherapy and IMRT. PATIENTS AND METHODS: Forty patients were randomized in two arms each consisting of 20 patients. Patients in both arms received concurrent chemoradiation (cisplatin 40mg/m(2) weekly; 50Gy/25 fractions). Patients were treated with 3D conformal radiotherapy in one arm and with IMRT in another arm. After external beam radiotherapy, all patients received brachytherapy (21Gy/3 fractions at weekly interval). For dosimetric comparison, both kinds of the plans were done for all the patients. All patients were assessed throughout and until 90 days after completion of treatment for acute gastrointestinal, genitourinary and hematologic toxicities. RESULTS: Both plans achieved adequate planning target volume coverage, while mean conformity index was found significantly better in IMRT plans (P-value=0.001). D35 (dose to 35% volume) and D50 for bladder was reduced by 14.62 and 32.57% and for rectum by 23.82 and 43.68% in IMRT. For IMRT, V45 (volume receiving 45Gy) of bowel were found significantly lesser (P-value=0.0001), non-tumour integral dose was found significantly higher (P-value=0.0240) and V20 of bone marrow was found significantly reduced (P-value=0.019) in comparison to that in 3D conformal radiotherapy. Significant reduction of grade 2 or more (20 vs 45%; P-value=0.058) and grade≥3 (5 vs 15%, P-value=0.004) acute genitourinary toxicity and grade 2 or more (20 vs 45%, P-value=0.003) and grade 3 or more (5 vs. 20%, P-value=0.004) acute gastrointestinal toxicity while no significant difference for grade 2 and 3 or more haematological toxicity was noted in patients treated with IMRT compared to 3D conformal radiotherapy. CONCLUSION: IMRT provide a good alternative for treatment of cervix carcinoma with lower acute gastrointestinal and acute genitourinary toxicity with similar target coverage compared to 3D conformal radiotherapy.


Asunto(s)
Carcinoma/terapia , Radioterapia Conformacional/efectos adversos , Radioterapia de Intensidad Modulada/efectos adversos , Neoplasias del Cuello Uterino/terapia , Adulto , Anciano , Anemia/etiología , Antineoplásicos/uso terapéutico , Braquiterapia , Carcinoma/patología , Quimioradioterapia , Cisplatino/uso terapéutico , Femenino , Tracto Gastrointestinal/efectos de la radiación , Humanos , Leucopenia/etiología , Persona de Mediana Edad , Estudios Prospectivos , Dosificación Radioterapéutica , Radioterapia Conformacional/métodos , Radioterapia de Intensidad Modulada/métodos , Índice de Severidad de la Enfermedad , Sistema Urinario/efectos de la radiación , Neoplasias del Cuello Uterino/patología , Vómitos/etiología
13.
Sci Rep ; 6: 27926, 2016 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-27297474

RESUMEN

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.

14.
Rev Sci Instrum ; 85(1): 013706, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24517774

RESUMEN

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.

15.
Ind Health ; 51(1): 113-22, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23411761

RESUMEN

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.


Asunto(s)
Temperatura Corporal , Cambio Climático , Trastornos de Estrés por Calor/etiología , Enfermedades Profesionales/etiología , Exposición Profesional/efectos adversos , Ocupaciones , Adulto , Femenino , Trastornos de Estrés por Calor/epidemiología , Humanos , India/epidemiología , Masculino , Enfermedades Profesionales/epidemiología , Medición de Riesgo , Factores de Riesgo , Estaciones del Año , Termografía/métodos
16.
Ind Health ; 48(3): 339-48, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20562510

RESUMEN

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.


Asunto(s)
Enfermedades Musculoesqueléticas/epidemiología , Enfermedades Profesionales/epidemiología , Factores Sexuales , Estrés Fisiológico , Estrés Psicológico/epidemiología , Industria Textil/estadística & datos numéricos , Adulto , Femenino , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Dolor/epidemiología , Prevalencia , Factores de Riesgo , Encuestas y Cuestionarios , Factores de Tiempo
18.
Appl Ergon ; 40(2): 286-91, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18508029

RESUMEN

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.


Asunto(s)
Sistemas Hombre-Máquina , Músculo Esquelético/fisiología , Postura/fisiología , Análisis y Desempeño de Tareas , Brazo , Dorso , Fenómenos Biomecánicos , Terminales de Computador , Electromiografía , Humanos , Masculino , Enfermedades Profesionales/fisiopatología , Muñeca , Adulto Joven
19.
Abdom Imaging ; 31(5): 582-7, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16465580

RESUMEN

BACKGROUND: Drugs such as secretin and morphine have been used to augment the visualization of magnetic resonance cholangiopancreatography (MRCP). This study investigated the effectiveness of intravenous administration of a synthetic opioid, fentanyl, in improving the MRCP image quality. METHODS: Thirty consecutive patients with a provisional diagnosis of benign biliary and/or pancreatic disease underwent MRCP. Coronal single-shot fast spin-echo heavily T2-weighted dynamic MRCP images were generated before and at every minute for 10 min after intravenous administration of fentanyl citrate at a dose of 1.0 mug/kg. Pre- and postinjection images were compared and analyzed qualitatively and quantitatively. RESULTS: Qualitatively, visualization of intrahepatic bile ducts, common bile duct, and main pancreatic duct improved after fentanyl injection in five (16%), 11 (37%), and 19 (63%) patients, respectively. The pancreatobiliary junction and common channel were visualized better after fentanyl injection in eight of the 18 patients (44%). Quantitatively, signal intensity and diameters of the intrahepatic ducts, common bile duct, and main pancreatic duct measured at corresponding points on pre- and postinjection images showed an increase above preinjection values in 28 (93%), 27 (90%), and 21 (70%) and in 18 (60%), 26 (86%), and 22 (73%), respectively, and these changes were highly significant at all sites (p < 0.001). CONCLUSIONS: Intravenous administration of fentanyl before MRCP improves qualitative and quantitative visualization of the ductal system anatomy that may be of value in clinical diagnosis and management.


Asunto(s)
Enfermedades de las Vías Biliares/diagnóstico , Pancreatocolangiografía por Resonancia Magnética/métodos , Fentanilo , Narcóticos , Enfermedades Pancreáticas/diagnóstico , Adolescente , Adulto , Niño , Preescolar , Femenino , Fentanilo/administración & dosificación , Humanos , Lactante , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Narcóticos/administración & dosificación
20.
Indian J Med Res ; 117: 260-9, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-14748472

RESUMEN

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.


Asunto(s)
Mano/anatomía & histología , Adolescente , Adulto , Antropometría , Ergonomía , Femenino , Humanos , India , Persona de Mediana Edad , Salud Laboral
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