Enhancing solar cells with localized plasmons in nanovoids.

Localized plasmon resonances of spherical nanovoid arrays strongly enhance solar cell performance by a factor of 3.5 in external quantum efficiency at plasmonic resonances, and a four-fold enhancement in overall power conversion efficiency. Large area substrates of silver nanovoids are electrochemically templated through self-assembled colloidal spheres and organic solar cells fabricated on top. Our design represents a new class of plasmonic photovoltaic enhancement: that of localized plasmon-enhanced absorption within nanovoid structures. Angularly-resolved spectra demonstrate strong localized Mie plasmon modes within the nanovoids. Theoretical modelling shows varied spatial dependence of light intensity within the void region suggesting a first possible route towards Third Generation plasmonic photovoltaics.

Repair of burns of the scrotum using a gracilis myocutaneous flap.

An unusual case of isolated burns of the scrotum reconstructed by a unilateral gracilis myocutaneous flap is reported because of its clinical rarity.

Time of firing of shot shells.

The possibility of ascertaining approximate time of firing by utilizing the phenomenon of rate of escape of gaseous products of combustion has been investigated with special reference to 12-bore, 2 1/2-in. (6.35-mm), fired cartridges made by the Indian Ordnance Factory. The relative rate of escape of gases has been determined indirectly by ascertaining the time needed to develop color in reagents by escaping gases by diazotization and coupling reaction. It has been observed that although the time to develop color tends to increase with the time lapse after firing, the observations are not interpretable for all possible time intervals due to overlapping and insignificant increase in certain intervals. A choice of suitable time intervals may be found to be useful in ascertaining the approximate time of firing, which may be determined experimentally in each case. Normal variation due to atmospheric conditions has been found not to have significant influence under certain limits. The method suggested has been found to be comparatively more useful than the already existing methods.

Atomic absorption spectrophotometric and X-ray studies of respirable dusts in Indian coal mines.

Quantitative determination of 10 minor and 8 trace elements in respirable coal dust by atomic absorption spectrophotometry is described herein. The coal dust samples were collected in the mine atmosphere during drilling in coal seams. A "Hexhlet" apparatus specially designed and fitted with a horizontal elutriator was used to collect the respirable coal dust fraction. After destruction of organic matter by wet oxidation and filtering off the clay and silica, iron, calcium, magnesium, sodium, potassium, manganese, zinc, copper, cadmium, and nickel were determined directly in the resulting solution by atomic absorption spectrophotometry. The studies relate to the respiratory disease-pneumoconiosis-affecting coal mine workers. X-Ray diffraction studies have shown the presence of kaolin, quartz, pirrsonite and beidellite clay minerals in the coal dust.

Temporomandibular ankylosis.

Temporomandibular ankylosis is commonly seen in children and young adults. Trauma in childhood is the commonest cause. Treatment of choice is by surgical intervention. Depending upon the local findings a gap arthroplasty or interposition arthroplasty is the procedure carried out. Early mobilisation is recommended.

Identification of tandem bullets.

The possibility of identifying tandem bullets, causing separate entry holes on one or two victims, or found separately at the scene of a crime, is investigated. The phenomenon of tandem bullets has been studied to evaluate the physical evidence. The presence of deep indentations of propellant particles on the exposed lead base cavity, along with patches of striations on the inner periphery of the cavity, have been found to be useful physical evidence to conclude that the bullet had moved in tandem and was a lodged bullet. An outward protrusion of the base acts as corroborative physical evidence that the bullet was the striking bullet.

Local steroid therapy in cutaneous hemangiomas.

OBJECTIVES: To evaluate the efficacy of intralesional triamcinolone in enhancing regression in various type of hemangiomas. SETTING: Outpatients department of a teaching hospital Subjects: One hundred and five patients with rapidly growing surface hemangioma. The age ranged from 1 month to 15 months (mean 7 months). INTERVENTION: Intralesional triamcinolone administered at monthly intervals, ranging from single injection to 7 injections (mean 3.6 injections). MAIN OUTCOME MEASURE: Regression of the hemangioma. RESULTS: The overall response rate was 88.6% (excellent 51.4%, and good 37.2%). Maximum response was observed in children below 1 year of age (> 90%), lesions over the face (92.8%) and strawberry hemangiomas (99.9%). CONCLUSION: Intralesional administration of triamcinolone devoid of systemic side effects and an effective initial modality for rapidly growing hermangiomas.

Increased macromolecular damage due to oxidative stress in the neocortex and hippocampus of WNIN/Ob, a novel rat model of premature aging.

Wistar of the National Institute of Nutrition obese (WNIN/Ob) is a unique rat strain isolated and established at NIN, Hyderabad, India, in 1996, from its existing stock of Wistar rat colony (WNIN). This animal model exhibits all traits of metabolic syndrome and has a remarkably reduced lifespan (1.5 years as compared to 3 years in parental WNIN rats), albeit, the factors associated with premature aging are not well understood. Considering that oxidative stress and DNA damage are crucial players associated with senescence, we analyzed oxidative stress markers like lipid peroxidation and protein oxidation; DNA damage in terms of both single-stranded and double-stranded breaks and the activity of antioxidant enzymes: superoxide dismutase and catalase in brain regions of these animals. Our study revealed that the magnitude of oxidative stress and DNA damage in the neocortex and hippocampus of 3-month-old WNIN/Ob obese rats is as high as that seen in 15-month-old parental WNIN control rats. Concurrently, the antioxidant enzyme activity was significantly decreased. From these results, it can be concluded that increased oxidative stress-induced damage of macromolecules, probably due to reduced activity of antioxidant enzymes, is associated with premature aging in WNIN/Ob obese rats.

Extensive facial damage caused by a blast injury arising from a 6 volt lead accumulator.

Low-voltage electrical injuries are relatively uncommon. Injury caused by flow of heavy current due to short-circuiting a low-voltage battery has not been described in the English literature. A 9-year-old boy connected two thin household electrical wires to the two terminals of a 6 volt (lead accumulator) battery and pressed the other two ends between his teeth. This resulted in a blast causing a compound comminuted fracture of the mandible and extensive tissue damage in the oral cavity. The low internal resistance of a lead accumulator (approximately 0.03 ohms) permits the flow of a heavy current (approximately 200 amps) when short-circuited. This instantaneously vaporises a minuscule portion of wire at approximately 2000 K resulting in a sudden rise of intraoral pressure to 30 kg cm-2 leading to tissue damage.

Management of scalp injuries.

Scalp avulsions of various origin are frequently seen, owing to rapid industrialization and the increased incidence of road-traffic accidents. This article deals with 20 such cases seen and treated by the authors in the last 5 years. The victims were predominantly young females. The anatomic and pathophysiologic aspects of avulsion injury are considered in detail, and various modalities of treatment are discussed. With intact pericranium, split-skin grafting remains the treatment of choice. In the presence of bare bone, local flap is preferred, if feasible. If not, then the outer table of the skull is chiseled out or multiple drilling is done through it to accelerate the formation of granulation tissue. Subsequently, this is covered by split-skin grafting. Of course, the grafts do not grow hair and the patients need to wear a wig for total psychological and functional rehabilitation. Prevention remains still the best remedy.

Traumatic avulsion of penile and scrotal skin.

Due to the use of high speed machinery in industry and the rapid mechanisation of agriculture an increasing number of avulsion injuries are being referred for treatment. This paper describes our experience in the management of ten patients with extensive traumatic avulsion of the penile and scrotal skin, treated by primary split-thickness skin grafting.

Macroradiographic study of post-burn contracture of limbs.

Fifty patients with post-burn contracture involving various joints of the limbs were analysed. To study the minor skeletal changes the patients were subjected to macroradiography. In half of the patients various types of pathology were observed and their therapeutic and prognostic significance have been discussed.

Respiratory functions in thermal burns.

In our present series, respiratory functions were observed in patients with a relatively small extent of burn compared to that commonly represented by the published works, and for a considerable duration of time (three weeks), commencing soon after the burn trauma. Respiratory rate increased in the post burn trauma and the peak expiratory rate was observed on the 8th post burn days and then it gradually fell but still remaining much higher than the control normal value. The minute volume and tidal volume also showed similar rise on the 8th post burn day and then gradually fell to below the mean level of 3rd post burn day before the 3rd post burn week. Forced vital capacity, forced expiratory volume in one second, forced expiratory volume in three seconds, forced expiratory volume in one second as a percentage of forced vital capacity, forced expiratory volume in three seconds, as a percentage of forced vital capacity and peak expiratory flow rates, did not vary much and indicated no significant respiratory abnormality.

Blood gas studies in thermal burns.

In the present study we have included 25 cases with a relatively small extent of burns as compared to those described in many of the other published work. We have chosen the 3rd post-burn day as the day of reference (because most of the patients did not turn up before that day) from which day onwards adequate number of observations were available. Arterial blood gas studies revealed significant decrease in arterial partial pressure oxygen on 5th and 8th post-burn days with lowest mean value on 8th post burn day and then a gradual rise towards the normal value. Arterial partial pressure of carbon dioxide fell after the burn to reach the lowest value on the 5th post burn day and then returned towards the normal value. Arterial hydrogen ion concentration also fell (i.e. arterial blood pH rise) in the post-burn course. This was significant on the 11th post burn day.