Microbiological strategies for enhancing biological nitrogen fixation in nonlegumes.

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.

Temporary anions of the dielectric gas C3F7CN and their decay channels.

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.

Prosthetic management of a hemimandibulectomy patient using tilted implant protocol with 3-year follow-up.

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.

Treatment of the Complete Edentulous Atrophic Maxilla: The Tall Tilted Pin Hole Placement Immediate Loading (TTPHIL)-ALL TILT™ Implant Option.

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.

Contrasting Dynamics in Isoelectronic Anions Formed by Electron Attachment.

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.

Tmem2 Deficiency Leads to Enamel Hypoplasia and Soft Enamel in Mouse.

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.

Distant Symmetry Control in Electron-Induced Bond Cleavage.

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.

Characterization of antisperm antibody binding patterns in relation to sperm phenotypic attributes and field fertility in dairy bulls.

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.

Intraluminal brachytherapy boost following external beam radiotherapy with concurrent chemotherapy of oesophagus carcinoma: Results of a prospective observational study.

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.

Effective Office Ergonomics Awareness: Experiences from Global Corporates.

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.

Web-based KAP Intervention on Office Ergonomics: A Unique Technique for Prevention of Musculoskeletal Discomfort in Global Corporate Offices.

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.

Comparison of dosimetric parameters and acute toxicity of intensity-modulated and three-dimensional radiotherapy in patients with cervix carcinoma: A randomized prospective study.

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.

Two distinct superconducting phases in LiFeAs.

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.

Androgenic regulation of steroid hormone receptor mRNAs in the brain of whiptail lizards.

Sex and species differences in androgenic regulation of steroid hormone receptor mRNAs were examined in the diencephalon of two species of whiptail lizards: Cnemidophorus inornatus is a sexual species and the direct evolutionary ancestor to Cnemidophorus uniparens, an all-female parthenogenetic species. Lizards were gonadectomized and treated with different doses of either aromatizable testosterone or nonaromatizable dihydrotestosterone. The relative abundances of androgen-, oestrogen-, and progesterone-receptor mRNAs were compared in various nuclei following in situ hybridization with homologous riboprobes. A diversity of patterns in androgenic regulation was observed, with effects differing according to brain region, the steroid-receptor mRNA being considered and, in some cases, between androgens. In the ancestral sexual species, intact males had lower androgen-receptor mRNA abundances than castrated, blank-implanted males in the medial preoptic area. Testosterone significantly decreased androgen-receptor mRNA abundance in the medial preoptic area of castrated males. Males had higher androgen-receptor mRNA levels in the preoptic area than females generally and neither the sexual or parthenogenetic females showed a decrease in androgen-receptor mRNA with androgen treatment. Both testosterone and dihydrotestosterone increased oestrogen-receptor mRNA abundance in the ventromedial hypothalamus of C. inornatus, but no sex differences in this effect were observed. Gonadectomy decreased, whereas androgen treatment increased, progesterone-receptor mRNA abundance in the ventromedial hypothalamus. There was a sex difference in this response to androgen in the sexual species, with males having greater amounts than females in this brain area. The parthenogenetic species exhibited a similar pattern to females of the sexual species, but the levels were higher overall, possibly because Cnemidophorus uniparens is triploid. The periventricular preoptic area showed a different pattern, with testosterone treatment increasing progesterone-receptor mRNA abundance in both sexes of the sexual species and in the parthenogenetic species, while dihydrotestosterone did not. The diversity of patterns in androgen effects indicates that gonadal sex, aromatization of androgen, and perhaps gene dosage all influence the expression of steroid-receptor mRNAs in the lizard brain.

Regulation of estrogen receptor and progesterone receptor messenger ribonucleic acid by estrogen in the brain of the whiptail lizard (Cnemidophorus uniparens).

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)

Species differences in estrogen receptor and progesterone receptor-mRNA expression in the brain of sexual and unisexual whiptail lizards.

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.

Hand anthropometry of Indian women.

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.

Human heat tolerance in simulated environment.

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).

Muscular strains in different modes of load handling.

The influence of posture on the ability of a person to hold loads was evaluated from a study on six healthy, young males. The muscle activities in terms of isometric strength and electromyographic (EMG) characteristics of the trunk and lower limb were determined in ten load-holding postures. The postures were comprised of trunk, knee and elbow in different straight and bent positions to include load heights (LH) of 32, 44, 85 and 125cm from the ground and subject-load distance (SLD) of 12 and 32cm. The pull-up maximum voluntary contraction (MVC) was significantly influenced by the SLD. The MVC values were consistently high with the increase in LH, when the SLD was 12 cm but the opposite was the case for SLD of 32 cm. The trunk-bent/knee-straight postures had higher MVC values (31 ± 8 to 34 ± 2·5 kgf) than those in knee-bent/trunk-straight postures (21 ± 3 to 28 ± 5 kgf). The trunk muscles behaved differently in trunk-straight and in bent postures. The hamstrings and quadriceps were counter-balanced in sharing loads during knee-bent or straight postures. It was observed that the load-holding operations were performed better in trunk-bent/knee-straight postures, and when the load was closer to the body at heights ranging from 32 to 44 cm. Whereas, in trunk and knee-straight postures, the pulling of the load was more convenient from waist height.

Endurance limits in different modes of load holding.

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.