Occupational heat stress and associated productivity loss estimation using the PHS model (ISO 7933): a case study from workplaces in Chennai, India

Background

Heat stress is a major occupational problem in India that can cause adverse health effects and reduce work productivity. This paper explores this problem and its impacts in selected workplaces, including industrial, service, and agricultural sectors in Chennai, India.

Design

Quantitative measurements of heat stress, workload estimations, and clothing testing, and qualitative information on health impacts, productivity loss, etc., were collected. Heat strain and associated impacts on labour productivity between the seasons were assessed using the International Standard ISO 7933:2004, which applies the Predicted Heat Strain (PHS) model.

Results and conclusions

All workplaces surveyed had very high heat exposure in the hot season (Wet Bulb Globe Temperature x¯ =29.7), often reaching the international standard safe work values (ISO 7243:1989). Most workers had moderate to high workloads (170–220 W/m²), with some exposed to direct sun. Clothing was found to be problematic, with high insulation values in relation to the heat exposure. Females were found to be more vulnerable because of the extra insulation added from wearing a protective shirt on top of traditional clothing (0.96 clo) while working. When analysing heat strain – in terms of core temperature and dehydration – and associated productivity loss in the PHS model, the parameters showed significant impacts that affected productivity in all workplaces, apart from the laundry facility, especially during the hot season. For example, in the canteen, the core temperature limit of 38°C predicted by the model was reached in only 64 min for women. With the expected increases in temperature due to climate change, additional preventive actions have to be implemented to prevent further productivity losses and adverse health impacts. Overall, this study presented insight into using a thermo-physiological model to estimate productivity loss due to heat exposure in workplaces. This is the first time the PHS model has been used for this purpose. An exploratory approach was taken for further development of the model.

Phase Diagram Studies on the Al- Ni System

The Al-Ni phase diagram has been investigated in the com position range xNi = 0.70 to 0.97. Phase boundaries were determined by using differential thermal analysis and Knudsen effusion mass spectrometry. The measurements were carried out in the temperature range between 1409 and 1730K. An Al-Ni phase diagram is obtained for xNi ≧ 0.70 by combining the data from this work with selected data from the literature. This diagram deviates from that recommended by phase diagram compilations and used generally in the literature to date; it agrees reasonably well with a diagram which has been rejected in the literature.

First case report of acute hemorrhagic leukoencephalitis following Plasmodium vivax infection

Acute hemorrhagic leukoencephalitis (AHLE, Hurst's disease) is a rare hyperacute variant of acute disseminated encephalomyelitis (ADEM) characterized by severe, rapidly progressive clinical illness and hemorrhagic necrosis of white matter. Like ADEM, it is often preceded by viral illness or vaccination. Plasmodium vivax infection is usually uncomplicated and non-fatal with only a handful of reports of central nervous system complications. In this article, we report a previously unknown association between AHLE and P. vivax infection.

Squamous cell carcinoma of penis with bullous pemphigoid masquerading as lymphogranuloma venereum

We report a case of a 60-year old unmarried male who presented with multiple ulcers and foul smelling discharge from the groin since 4 months and multiple tense bullae over the trunk of 1 month duration. Groove sign was present. Investigations for lymphogranuloma venereum (LGV) and other sexually transmitted diseases were negative. Histopathology from the ulcer in the groin and growth in the penis revealed squamous cell carcinoma (SCC). Skin biopsy of bulla was diagnostic of bullous pemphigoid (BP). We report a rare case of SCC masquerading as LGV with BP occurring as a paraneoplastic phenomenon.

Woolly hair nevus: a rare entity

Woolly hair nevus is a rare non-hereditary focal condition characterized by unruly and tightly coiled hair. It can appear in childhood or adolescence and may be associated with epidermal or melanocytic nevus. Patients presenting with woolly hair must be examined completely to rule out cardiofaciocutaneous and Noonan syndrome.

Secondary lymphangioma of vulva: a report of two cases

Secondary lymphangiomas or acquired lymphangiomas of vulva represent dilatation of upper dermal lymphatics following damage to previously normal deep lymphatics. They have been reported to occur following various infections, surgeries and radiotherapy which can cause damage to deep lymphatics.Treatment options in the management of secondary lymphangiomas include surgical resection, carbon dioxide laser vaporisation, sclerosing agents etc. We report two cases of secondary lymphangioma of vulva that followed radiotherapy for carcinoma of cervix. Both the patients were treated successfully by surgery.

Poisoning and non-poisoning oxygen on Cu(410)

We have investigated ethene and oxygen co-adsorption on Cu(410) by high resolution electron energy loss spectroscopy. We find that these two species compete for the adsorption sites and that pre-exposure to oxygen affects ethene adsorption more or less strongly depending on oxygen coverage and the kind of occupied sites. The c(2 × 2) O overlayer is inert with respect to ethene adsorption, while when some oxygen is removed by thermally induced subsurface incorporation, ethene chemisorption is restored. The latter species also adsorbs on the disordered oxygen phase formed when O(2) is dosed at low crystal temperature. Contrary to the bare surface case, most of the ethene ends up in a π-bonded configuration. Dehydrogenation occurs, too, albeit as a minority channel. The so-produced carbon reacts already at low temperature with adsorbed oxygen to yield carbon monoxide, which desorbs around 190 K.

Air pollution from household solid fuel combustion in India: an overview of exposure and health related information to inform health research priorities

Environmental and occupational risk factors contribute to nearly 40% of the national burden of disease in India, with air pollution in the indoor and outdoor environment ranking amongst leading risk factors. It is now recognized that the health burden from air pollution exposures that primarily occur in the rural indoors, from pollutants released during the incomplete combustion of solid fuels in households, may rival or even exceed the burden attributable to urban outdoor exposures. Few environmental epidemiological efforts have been devoted to this setting, however. We provide an overview of important available information on exposures and health effects related to household solid fuel use in India, with a view to inform health research priorities for household air pollution and facilitate being able to address air pollution within an integrated rural-urban framework in the future.

On the application of electrochemical techniques for the preparation of 57Co source core, encapsulation and quality evaluation for radiometric assay of nuclear fuel rods

This paper describes an electrochemical method for the preparation of 57Co source to be used in quality evaluation of nuclear fuel rods. The electrolytic cell, the experimental set up used and the process of deposition are described. The effect of various parameters such as pH of the electrolyte, bath temperature, current density, content of cobalt in the bath, electrolyte volume in the cell and deposition time were investigated and optimized for maximum deposition. The texture and morphology of the electrodeposited samples were examined by X-ray diffraction (XRD), SEM and EDS analyses. Sources containing ∼370 MBq (10 mCi) 57Co on a circular copper foil of 4 mm diameter could be prepared and encapsulated in an aluminum capsule. Quality assurance tests performed to ensure non-leachability, uniform distribution of activity and stability of the sources gave satisfactory results.

Fixation of some major fission products in NaZr2P3O12 ceramic employing microwave heating

Attempts were made to introduce four major fission products, namely, Cs, Sr, Ru and Te into thermodynamically stable NaZr2P3O12 (NZP) ceramic, considered to be a viable alternative for fixation of high level nuclear waste (HLW), in place of borosilicate glass. The results showed that all these elements could be incorporated in NZP at temperatures as low as 723 K by heating the reaction mixtures in a microwave heating system. Among the four elements introduced in NZP, except for Te, all others were retained nearly quantitatively in samples heated to 1273 K for three hours. The tellurium substituted NZP exhibited the maximum loss exceeding the amount of TeO2 added, which could probably be due to formation of some volatile compounds by TeO2 with the elements in the NZP matrix. Addition of Sr and Te simultaneously in NZP decreased the amount of TeO2 loss considerably.

Studies on the dissolution behaviour of ThO2 and (U,Th)O2 by a solid state reaction method

A simple and fast method for the dissolution of sintered ThO2 and (U,Th)O2 was developed. The products formed when these oxides were fused with ammonium sulphate at various temperatures were found to be readily soluble in dilute nitric acid. Among all the products obtained at various temperatures, (NH4)2 Th (SO4)3 and (NH4)2(Ux,Th1-x)(SO4)3, obtained at 365 °C, were found highly soluble (>99%). After dissolution thorium was separated selectively by oxalate precipitation method. More than 95% of uranium was recovered from the solution by ammonium diuranate precipitation method. The products formed at different temperatures were characterised by X-ray, thermal and chemical analysis techniques.

Fluoride determination in various matrices relevant to nuclear industry: A review

The determination of fluoride from diverse matrices at front and back end of nuclear technology and some studies from this laboratory on optimizations of different experimental parameters differing with multiple fuels and reactor materials, have been reviewed. The most useful techniques such as fluoride ion selective electrode (F-ISE) and ion-chromatography (IC) widely adopted as routine methods for fluoride determination in nuclear industry have been discussed. The effect of various buffer strengths on the response of the fluoride ion selective electrode has been examined. The ion chromatographic studies on mobile phase concentration, medium of sample, sample injection volume etc. to get distinct fluoride peak within optimum time in presence of other anionic species in diverse concentrations have been reported. The results of various sample matrices such as UO2, PuO2, (U,Pu)O2, Pu-alloy, thoria, zircaloy, slag, HLLW, LLLW etc., analyzed after matrix separation using pyrohydrolysis setup, for both solid and liquid samples and without matrix separation by masking potentially interfering ions of liquid samples, have been presented.

Ion exchange studies for the removal of plutonium and americium from organic liquid scintillator waste solution

Removal of radioactive nuclides from effluents is important for the safe disposal of the radioactive waste. In the present work ion exchange studies were carried out using simulated alpha active organic liquid scintillator and ethyl alcohol waste solutions containing Pu and Am using different resins. The time of equilibration and batch data were obtained under different conditions for individual resins as well as their mixtures. The indigenously developed Macroporous bifunctional phosphinic acid (MPBPA) resin was found to be suitable for the removal of alpha activity mainly due to Pu and Amberlite IR-120 and Biorad 50W × 8 for removal of Am. The results indicated that the presence of alcohol in the scintillator solution helps in increasing the distribution ratio. Experiments were carried out with column containing either MPBPA resin alone or with additional resin bed of Amberlite IR-120 using active organic liquid scintillator waste (with and without dilution with alcohol). Studies were also carried out on alcoholic waste generated in the laboratory during the washing of the used liquid scintillator vials. The alcohol after removal of activity either could be reused or could be disposed off directly as a ‘potentially’ active waste.

Removal of radioactive caesium from low level radioactive waste (LLW) streams using cobalt ferrocyanide impregnated organic anion exchanger

The volumes of low level waste (LLW) generated during the operation of nuclear reactor are very high and require a concentration step before suitable matrix fixation. The volume reduction (concentration) is achieved either by co-precipitating technique or by the use of highly selective sorbents and ion exchange materials. The present study details the preparation of cobalt ferrocyanide impregnated into anion exchange resin and its evaluation with respect to removal of Cs in LLW streams both in column mode and batch mode operations. The Kd values of the prepared exchanger materials were found to be very good in actual reactor LLW solutions also. It was observed that the exchanger performed very well in the pH range of 3-9. A batch size of 6 g l(-1) of the exchanger was enough to give satisfactory decontamination for Cs in actual reactor LLW streams. The lab scale and pilot plant scale performance of the exchanger material in both batch mode and column mode operations was very good.

Remote ischaemic preconditioning reduces myocardial injury in patients undergoing cardiac surgery with cold-blood cardioplegia: a randomised controlled trial

BACKGROUND

Remote ischaemic preconditioning (RIPC) induced by brief ischaemia and reperfusion of the arm reduces myocardial injury in coronary artery bypass (CABG) surgery patients receiving predominantly cross-clamp fibrillation for myocardial protection. However, cold-blood cardioplegia is the more commonly used method world wide.

OBJECTIVE

To assess whether RIPC is cardioprotective in CABG patients receiving cold-blood cardioplegia.

DESIGN

Single-centre, single-blinded, randomised controlled trial.

SETTING

Tertiary referral hospital in London.

PATIENTS

Adults patients (18-80 years) undergoing elective CABG surgery with or without concomitant aortic valve surgery with cold-blood cardioplegia. Patients with diabetes, renal failure (serum creatinine >130 mmol/l), hepatic or pulmonary disease, unstable angina or myocardial infarction within the past 4 weeks were excluded.

INTERVENTIONS

Patients were randomised to receive either RIPC (n = 23) or control (n = 22) after anaesthesia. RIPC comprised three 5 min cycles of right forearm ischaemia, induced by inflating a blood pressure cuff on the upper arm to 200 mm Hg, with an intervening 5 min reperfusion. The control group had a deflated cuff placed on the upper arm for 30 min.

MAIN OUTCOME MEASURES

Serum troponin T was measured preoperatively and at 6, 12, 24, 48 and 72 h after surgery and the area under the curve (AUC at 72 h) calculated.

RESULTS

RIPC reduced absolute serum troponin T release by 42.4% (mean (SD) AUC at 72 h: 31.53 (24.04) microg/l.72 h in controls vs 18.16 (6.67) microg/l.72 h in RIPC; 95% CI 2.4 to 24.3; p = 0.019).

CONCLUSIONS

Remote ischaemic preconditioning induced by brief ischaemia and reperfusion of the arm reduces myocardial injury in CABG surgery patients undergoing cold-blood cardioplegia, making this non-invasive cardioprotective technique widely applicable clinically.

TRIAL REGISTRATION NUMBER

NCT00397163.

Amino acid residues of Leishmania donovani cyclophilin key to interaction with its adenosine kinase: biological implications

Cyclophilins (CyPs), by interacting with a variety of proteins, often modulate their biological activities and thus have been implicated in several cellular functions. However, mechanisms that determine such interactions are poorly understood. We earlier reported that an endoplasmic reticulum (ER)-located cyclophilin (LdCyP) from the purine auxotrophic parasitic protozoan Leishmania donovani reactivated its adenosine kinase (AdK). The AdK-reactivating property of LdCyP was however abolished at high ionic strength but not by nonionic detergents. Modeling of LdCyP, based on its crystal structure solved at 1.97 A resolution, revealed several solvent-exposed hydrophobic and charged residues. Mutagenesis of several of such solvent-exposed residues was performed and their corresponding activities with regard to their (i) AdK reactivation property, (ii) ability to form complex with the enzyme, (iii) capacity to induce red shift in the intrinsic tryptophan fluorescence maxima of AdK, and (iv) efficiency to withdraw the ADP inhibition from the AdK-mediated reaction were compared to the wild-type protein. Results indicated that while the replacement of R147 with either A or D severely impaired all of the above characteristics displayed by the wild-type LdCyP, the effect of mutating K114 and K153 was although relatively less but nevertheless noticeable. Alteration of other exposed hydrophobic and charged residues apparently did not have any discernible effect. Under the condition of cellular stress, the ER-located LdCyP is released into the cytoplasm with concomitant increase both in the specific activity of the cytosol-resident AdK and the uptake of radiolabeled Ado into the cells. These experiments, besides demonstrating the importance of the positive charge, identified R147 as the most crucial residue in the LdCyP-AdK interaction and provide evidence for the stress-induced retrograde translocation of LdCyP from the ER to the cytoplasm. A possible implication of this interaction in the life cycle of the parasite is proposed.

An outbreak of Paederus dermatitis in a suburban hospital in South India: a report of 123 cases and review of literature

BACKGROUND

Paederus dermatitis is a peculiar irritant contact dermatitis caused when beetles of the genus Paederus (often called rove beetles) are crushed on the skin, releasing the vesicant pederin. The dermatitis is most frequently seen in regions with a hot, tropical climate.

METHODS

We describe 123 patients who presented to our dermatology department at a suburban teaching hospital located in Tamilnadu, South India, known for its long, hot summers. Ours was a 1-year prospective study (January 2005 to December 2005).

RESULTS

The peak time of presentation was during April. The mean duration of lesions before presentation was 2.7 days. The neck and arms were the most common sites of involvement. Male patients outnumbered female patients in our study (males 65%, females 35%). The mean age of patients was 23.4 years. Clinically, the most common presentation consisted of linear, geographic, erythematous plaques with a "burnt" appearance. In 61% of patients, more than one lesion was present. Vesicles were seen in 33.3% of patients and pustules in 4.9% of patients. "Kissing lesions" were seen in 1.6% of patients. Periorbital involvement occurred in 4.9% of patients. The majority of patients were students residing in various hostels in our campus, within 1 km of rice fields.

LIMITATIONS

Species identification of the Paederus beetles was not done. In addition, skin biopsy of the lesions was not done and no histopathologic examination was performed.

CONCLUSION

An outbreak of paederus dermatitis can occur in tropical regions. Awareness of the condition and its clinical features will prevent misdiagnosis. Simple preventive measures can be undertaken based on the behavioral pattern of this nocturnal beetle.

Plica polonica in association with pediculosis capitis and scabies - a case report

Plica polonica is a rare disorder of hair in which groups of hair shafts become irreversibly entangled, forming a matted, malodorous and encrusted, sticky, moist mass. Various predisposing factors are known to cause this condition. We report one such case associated with pediculosis capitis and scabies.

Structure of cyclophilin from Leishmania donovani at 1.97 A resolution

The crystal structure of cyclophilin from Leishmania donovani (LdCyp) has been determined and refined at 1.97 A resolution to a crystallographic R factor of 0.178 (R(free) = 0.197). The structure was solved by molecular replacement using cyclophilin from Trypanosoma cruzi as the search model. LdCyp exhibits complete structural conservation of the cyclosporin-binding site with respect to the homologous human protein, as anticipated from LdCyp-cyclosporin binding studies. Comparisons with other cyclophilins show deviations primarily in the loop regions. The solvent structure encompassing the molecule has also been analyzed in some detail.

Increasing trend of extreme rain events over India in a warming environment

Against a backdrop of rising global surface temperature, the stability of the Indian monsoon rainfall over the past century has been a puzzle. By using a daily rainfall data set, we show (i) significant rising trends in the frequency and the magnitude of extreme rain events and (ii) a significant decreasing trend in the frequency of moderate events over central India during the monsoon seasons from 1951 to 2000. The seasonal mean rainfall does not show a significant trend, because the contribution from increasing heavy events is offset by decreasing moderate events. A substantial increase in hazards related to heavy rain is expected over central India in the future.

Stimulation of pigment accumulation in Anabaena azollae strains: effect of light intensity and sugars

The influence of high light intensity on the growth and pigment accumulating ability of Anabaena azollae was investigated. A. azollae responded positively to high light intensity (6 klx) and was further evaluated at higher intensities (10 and 15 klx), in the presence of glucose, sucrose and jaggery +/- DCMU. Significant enhancement in phycobiliproteins and carotenoids was observed in the sugar supplemented cultures at high light intensities. SDS-PAGE profiles of whole cell proteins revealed the presence of unique bands in such treatments. Sucrose supplementation induced a 30-90 % increase in carotenoids, phycocyanin and phycoerythrin content at 10 klx. Molecular analysis of the stimulatory and interactive role of sugars on pigment enhancement at high light intensity may aid in better exploitation of cyanobacteria as a source of pigments.

New Modes of Coordination for the β-Disulfoxide Ligand. The Crystal and Molecular Structure of [{UO2(DBM)2}2PhSOCH2SOPh]

The X-ray structure of the compound [{UO2(DBM)2}2C6H5SOCH2SOC6H5] confirms the bridging bidentate mode of coordination for the β-disulfoxide ligand C6H5SOCH2SOC6H5.