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Plant genetic resource collection expedition across various parts of India and herbarium study of Amaranthus and Luffa genera at Botanical Survey of India (BSI), Kolkata and Coimbatore revealed the distribution of 18 plant taxa new to various Indian states/union territory, viz., Arunachal Pradesh (7), Andaman & Nicobar Islands (5), Jammu & Kashmir (3), Andhra Pradesh (2), Manipur (1), and Tamil Nadu (1). Out of these, 14 taxa have importance as wild relatives of 12 crop species. In addition, herbarium studies at the BSI, Kolkata revealed the natural distribution of a cucurbitaceous species – Siraitia siamensis in Myanmar, which remained unnoticed and unreported so far. Locality of herbarium/ germplasm collection, habitat and other field observations have been highlighted here.

Field surveys across various parts of the country coupled with an analysis of literature and examination of herbarium specimens revealed the natural distribution of six wild relatives of crop species in various states/union territories of India, viz., Cajanus scarabaeoides (from Lakshadweep), Cucumis javanicus (from Meghalaya), Hystrix duthiei (from Jammu & Kashmir), Luffa echinata (from Haryana) and Trichosanthes pilosa (from Andhra Pradesh), which have not been reported earlier from these states. Their descriptions, phenology, habitat and other field notes have been presented here.

Background and objective Hypoglycemia is a major hindrance for optimal glycemic control in women with gestational diabetes mellitus[GDM] on insulin. We objectively estimated masked hypoglycemia [glucose

During survey and exploration undertaken for collection of germplasm of crop wild relatives from terai region (foothills) of Uttarakhand and parts of Uttar Pradesh, a wild species of okra [Abelmoschus manihot (L.) Medik. subsp. tetraphyllus (Roxb. ex Hornem.) Borss. Waalk.] locally called “Sukhlai” being used as organic clearant in small scale jaggery industry was reported for the first time under cultivation in farmers’ field. There is no specific documentation on its commercial cultivation for the above use. Variability study was undertaken for cultivated and wild types in areas of exploration to work out trends of domestication. Brief information on botany, distribution, genetic resource value and methodology of use of the species in jaggery industry has been discussed.

A pulsatile pattern of secretion is a characteristic of many hormonal systems, including the glucocorticoid-producing hypothalamic–pituitary–adrenal (HPA) axis. Despite recent evidence supporting its importance for behavioral, neuroendocrine and transcriptional effects of glucocorticoids, there has been a paucity of information regarding the origin of glucocorticoid pulsatility. In this review we discuss the mechanisms regulating pulsatile dynamics of the HPA axis, and how these dynamics become disrupted in disease. Our recent mathematical, experimental and clinical studies show that glucocorticoid pulsatility can be generated and maintained by dynamic processes at the level of the pituitary–adrenal axis, and that an intra-adrenal negative feedback may contribute to these dynamics.

Chinese chives (Allium tuberosum Rottler ex Sprengel) is a less known cultivated vegetable in western and eastern Himalayan regions of India. This species is reported here for its potential for commercialization to supplement the onion and garlic production in different parts of India especially under the present unpredictable climatic conditions. Due to multipurpose use and wider adaptability of the species future thrust is laid on collection and conservation programmes in India.

A morphotype of chinese chives (Allium tuberosum Rottler ex Spreng.) with pink mid-vein in white tepals on the abaxial surface growing in Leh, Ladakh (Jammu & Kashmir), India was studied on a comparative account with common type A. tuberosum (white tepals with green mid-vein) and a close wild relative, A. ramosum L. Allium subg. Butomissa (Salisb.) N. Friesen is discussed here with reference to taxa in India based on the study undertaken using observations from field, experimental, ecogeographical, herbarium and molecular data. A key is provided with some characters previously not included in the available diagnostic keys. Issues relating to use of terminology for plant characters are provided to the facilitate fi eld identification.

Background The 7.5-kb chlamydial cryptic plasmid remains a widely used sequence target for Chlamydia trachomatis nucleic acid amplification tests, but sequence variation in this plasmid, particularly a previously reported 377-bp deletion, can cause false-negative results. Here we report the presence in Australia of a C. trachomatis strain lacking the cryptic plasmid. Methods: A rectal swab from a male in his 50s provided a positive result for C. trachomatis using the Roche Cobas 4800 test, but a negative result in our confirmatory in-house polymerase chain reaction (PCR) method targeting the chlamydial cryptic plasmid. This result was unexpected given our in-house PCR assay targeted a region of sequence outside the recognised 377-bp deletion. To further investigate this discrepancy, the sample was retested using a second in-house PCR targeting a chromosomal (ompA) gene as well as six primer sets flanking various regions of the cryptic plasmid. Results: The sample provided positive results in the second in-house method, confirming the presence of C. trachomatis DNA. All other primer sets targeting the cryptic plasmid failed to amplify, indicating a lack of the chlamydial cryptic plasmid in this sample. Conclusions: The recognition of a plasmid-deficient strain of C. trachomatis within Australia highlights further limitations of using the chlamydial cryptic plasmid for C. trachomatis diagnostics and re-emphasises the benefits of using multitarget assays to avoid false-negative results.

Hypoglycemia is a major hindrance for optimal glycemic control in women with gestational diabetes mellitus (GDM) on insulin. In the present study, masked hypoglycemia (glucose2.77mmol/L for ≥30 min) was estimated in pregnant women using a continuous glucose monitoring (CGM) system.Twenty pregnant women with GDM on insulin (cases) and 10 age-matched euglycemic pregnant women (controls) between 24 and 36 weeks gestation were recruited. Both groups performed self-monitoring of blood glucose (SMBG) and underwent CGM for 72 h to assess masked hypoglycemia. Masked hypoglycemic episodes were further stratified into two groups based on interstitial glucose (2.28-2.77 and ≤2.22 mmol/L).Masked hypoglycemia was recorded in 35% (7/20) of cases and 40% (4/10) of controls using CGM, with an average of 1.28 and 1.25 episodes per subject, respectively. Time spent at glucose levels between 2.28 and 2.77 mmol/L did not differ between the two groups (mean 114 vs 90 min; P = 0.617), but cases spent a longer time with glucose ≤2.2 mmol/L. Babies born to women with GDM were significantly lighter than those born to controls (2860 vs 3290 g; P = 0.012). There was no significant difference in birth weight within the groups among babies born to women with or without hypoglycemia.Euglycemic pregnant women and those with GDM on insulin had masked hypoglycemia. Masked hypoglycemia was not associated with adverse maternal or fetal outcomes. Therefore, low glucose levels in the hypoglycemic range may represent a physiologic adaptation in pregnancy. This response is exaggerated in women with GDM on insulin.

Bacterial diseases, diarrhoea, cholera, typhoid and dysentery mainly originate through consumption of bacterial contaminated water. Comparative in-vitro antimicrobial activity of some essential oils (EOs) against a few water borne bacterial diseases are reported. The minimum inhibitory concentrations (MIC) of essential oil of Micromeria biflora Benth for Escherichia coli (ATCC-25922), E. coli (MTCC-723), Shigella dysenteriae (ATCC-23513) Salmonella typhimurium (MTCC-98) respectively was 0.172, 0.308, 0.178, 0.202 mg/ml but in case of Vibrio cholerae (MTCC-3906) the oil was found ineffective. The essential oil of Citrus reticulata Blanco had MIC against E. coli 2.60 mg/ml, V. cholerae 8.06 mg/ml, S. dysenteriae 2.99 mg/ml, S. typhimurium 5.18 mg/ml, but the oil has no efficacy against E. coli (MTCC). Further, due to synergistic activity, the oils were found to be more effective against MTCC strain of E. coli and V. cholerae at MIC of 0.15 and 0.14 mg/ml respectively. The phylogenetic evaluations of the pathogens were carried out with help of ClustalW computer program.

Medicinal plants are facing threats due to loss of habitat and overexploitation of knows species. Therefore the present work shows utilization of essential oil from discarded leaves of Psidium guajava Linn. against human dermatophytic fungi Trichophyton rubrum, T. mentagrophytes, Trichophyton violaceum, Trichophyton tonsurans, Epidermophyton floccosum, Microsporum gypseum and Microsporum canis. The oil was found to be fungicidal at 3.0 μl/ml and it tolerated heavy inoculum of pathogens at fungicidal concentrations. The fungicidal activity of the oil was thermostable, up to 70°C and shelf life was found to be six months, which was maximum the time taken into consideration. The oil having cineole, caryophyllane, copaene, azulene and eucalyptol as main constituents, exhibited broad fungicidal activity. The oil did not show any adverse effect on mammalian skin upto 5% concentration. Phylogeny of the dermatophytes with respect to toxicity of the oil has also been discussed using molecular data. The cost effective formulation from waste leaves can be exploited after undergoing double blind successful multicentral topical testing.

Milk fat is a natural product containing essential nutrients as well as fatty acids and other food factors with reported anti-cancer potential. Here bovine milk fat was tested for its ability to inhibit the growth of breast and colon cancers and their metastasis to the lung and liver; either alone or in combination with the chemotherapeutic agent paclitaxel. A diet containing 5% typical anhydrous milk fat (representing ~70% of the total dietary fat component) fed to Balb/c mice delayed the appearance of subcutaneous 4T1 breast and CT26 colon cancer tumours and inhibited their metastasis to the lung and liver, when compared to the control diet containing soybean oil as the only fat component. It augmented the inhibitory effects of paclitaxel on tumour growth and metastasis, and reduced the microvessel density of tumours. It displayed no apparent organ toxicity, but instead was beneficial for well-being of tumour-bearing mice by maintaining gastrocnemius muscle and epididymal adipose tissue that were otherwise depleted by cachexia. The milk fat diet ameliorated gut damage caused by paclitaxel in non-tumour-bearing mice, as evidenced by retention of jejunal morphology, villi length and intestinal γ-glutamyl transpeptidase activity, and inhibition of crypt apoptosis. It prevented loss of red and white blood cells due to both cancer-mediated immunosuppression and the cytotoxic effects of chemotherapy. The present study warrants the use of milk fat as an adjuvant to inhibit tumour metastasis during cancer chemotherapy, and to spare patients from the debilitating side-effects of cytotoxic drugs.

Adenosine is a constitutive cell metabolite with a putative role in protection and regeneration in many tissues. This study was undertaken to determine if adenosine signalling pathways are involved in protection against noise injury. A1 adenosine receptor expression levels were altered in the cochlea exposed to loud sound, suggesting their involvement in the development of noise injury. Adenosine and selective adenosine receptor agonists (CCPA, CGS-21680 and Cl-IB-MECA) were applied to the round window membrane of the cochlea 6 h after noise exposure. Auditory brainstem responses measured 48 h after drug administration demonstrated partial recovery of hearing thresholds (up to 20 dB) in the cochleae treated with adenosine (non-selective adenosine receptor agonist) or CCPA (selective A1 adenosine receptor agonist). In contrast, the selective A2A adenosine receptor agonist CGS-21680 and A3 adenosine receptor agonist Cl-IB-MECA did not protect the cochlea from hearing loss. Sound-evoked cochlear potentials in control rats exposed to ambient noise were minimally altered by local administration of the adenosine receptor agonists used in the noise study. Free radical generation in the cochlea exposed to noise was reduced by administration of adenosine and CCPA. This study pinpoints A1 adenosine receptors as attractive targets for pharmacological interventions to reduce noise-induced cochlear injury after exposure.

This review describes the nature and applications of ribosome inactivating proteins (RIPs) from Momordica charantia (bitter melon). RIPs from the plant kingdom have received much attention in biomedical research because they target conserved host protein synthesis machinery and show specificity towards human and animal cell targets. Recent studies aimed at unravelling the enzymatic activities of the M charantia RIPs provide a structural basis for their activities. It has been reported that RIPs are member of the single chain ribosome inactivating protein (SCRIP) family which act irreversibly on ribosome by removing adenine residue from eukaryotic ribosomal RNA. Various activities of RIPs include anti-tumor, broad anti-viral, ribonuclease and deoxyribonuclease. MAP30 (Momordica Anti-HIV Protein), alpha- and beta-momorcharins inhibit HIV replication in acutely and chronically infected cells and thus are considered potential therapeutic agent in HIV infection and AIDS. Further, MAP30 improved the efficacy of anti-HIV therapy when used in combination with other anti-viral drugs. MAP30 holds therapeutic promise over other RIPs because not only it is active against infection and replication of both HSV and HIV but is non toxic to normal cells. Here we review the nature, action, structure function relationship and applications of RIPs from Momordica charantia and evaluate their potential for anti-cancer and anti-viral therapy.

Objectives: We determined the frequencies of (1) female patients aged 65 years and older having bone density measurement performed and (2) prescription therapy use among osteoporotic women. Methods: We completed a retrospective chart audit to assess our adherence to Physician Quality Reporting Initiative guidelines. Women aged 65 to 75 with an office visit between June 1 to November 30, 2007, were divided into 3 subgroups: those who had a recent preventive general medical examination (GME), those who received one in the last 10 years, and those who had not. We determined osteoporosis screening rates for all 3 groups. The first group then underwent electronic medical record review to obtain patient demographics, determine bone mineral density results, and review if those with osteoporosis were receiving prescription treatment. Results: Ninety-six percent of 305 female patients seen for a GME during the study period had completed bone mineral density testing. This was a screening rate significantly greater than that for patients with an earlier GME and those who never had one in our offices (70% and 50%, respectively). Seventy-seven percent of recent GME patients had abnormal T scores. Low weight and body mass index were significantly associated with osteoporotic T scores. Seventy-four percent of patients whose latest T scores were less than −2.5 were receiving prescription therapy. Conclusions: Female patients who completed a recent GME had extraordinarily high rates of screening for osteoporosis. We believe this demonstrates the importance of a dedicated preventive health examination as well as the increased significance that physicians and patients currently place on this behavior.

Bovine lactoferrin (bLf), an iron-containing natural defence protein found in bodily secretions, has been reported to inhibit carcinogenesis and the growth of tumours. Here, we investigated whether natural bLf and iron-saturated forms of bLf differ in their ability to augment cancer chemotherapy. bLf was supplemented into the diet of C57BL/6 mice that were subsequently challenged subcutaneously with tumour cells, and treated by chemotherapy. Chemotherapy eradicated large (0.6 cm diameter) EL-4 lymphomas in mice that had been fed iron-saturated bLf (here designated Lf(+)) for 6 weeks prior to chemotherapy, but surprisingly not in mice that were fed lesser iron-saturated forms of bLf, including apo-bLf (4% iron saturated), natural bLf (approximately 15% iron saturated) and 50% iron-saturated bLf. Lf(+)-fed mice bearing either EL-4, Lewis lung carcinoma or B16 melanoma tumours completely rejected their tumours within 3 weeks following a single injection of either paclitaxel, doxorubicin, epirubicin or fluorouracil, whereas mice fed the control diet were resistant to chemotherapy. Lf(+) had to be fed to mice for more than 2 weeks prior to chemotherapy to be wholly effective in eradicating tumours from all mice, suggesting that it acts as a competence factor. It significantly reduced tumour vascularity and blood flow, and increased antitumour cytotoxicity, tumour apoptosis and the infiltration of tumours by leukocytes. Lf(+) bound to the intestinal epithelium and was preferentially taken up within Peyer's patches. It increased the production of Th1 and Th2 cytokines within the intestine and tumour, including TNF, IFN-gamma, as well as nitric oxide that have been reported to sensitize tumours to chemotherapy. Importantly, it restored both red and white peripheral blood cell numbers depleted by chemotherapy, potentially fortifying the mice against cancer. In summary, bLf is a potent natural adjuvant and fortifying agent for augmenting cancer chemotherapy, but needs to be saturated with iron to be effective.

(2007). La promotion du poker sur Internet et son influence sur la participation des jeunes adultes aux jeux d’argent. Loisir et Societe / Society and Leisure: Vol. 30, No. 2, pp. 513-526.

Study objectives To determine whether, in patients with bilateral pleural effusions, the main cellular and biochemical features of the pleural fluid on the right side differ from or correlate with those on the left side. We examined lactate dehydrogenase (LDH), glucose, and total protein (TP) levels, RBC count, nucleated cell count (NCC), and differential cell count. Patients and methods Twenty-seven patients with bilateral pleural effusions, including 13 patients with effusions after coronary artery bypass graft surgery, 12 patients with congestive heart failure, 1 patient with malignant pericarditis, and 1 patient with renal failure, were studied retrospectively. Results The right-sided and the left-sided pleural effusions did not differ in the mean TP (p = 0.38), glucose (p = 0.31), and LDH (p = 0.39) levels, RBC count (p = 0.31), NCC (p = 0.96), and the percentage of neutrophils (p = 0.22), lymphocytes (p = 0.73), mononuclear cells (MNCs) [p = 0.49], and eosinophils (p = 0.65). The bias ± precision was 0.1 ± 0.64 g/dL for TP, − 2.7 ± 23 mg/dL for glucose, 41 ± 362 IU/L for LDH, 6,100 ± 62,900 cells/μL for RBC count, − 36 ± 1,043 cells/μL for NCC, − 2.9 ± 11.6% for the percentage of neutrophils, 1.15 ± 17% for the percentage of lymphocytes, 2.3 ± 17% for the percentage of the MNCs, and − 0.15 ± 5.4% for the percentage of eosinophils. Moreover, there was a close correlation between the right-sided and the left-sided pleural effusions concerning TP level ( r = 0.85, p r = 0.78, p r = 0.71, p r = 0.66, p r = 0.60, p = 0.001), and the percentage of neutrophils ( r = 0.77, p r = 0.77, p r = 0.74, p r = 0.84, p Conclusion Since the pleural fluid findings tend to be similar in both sides of patients with bilateral pleural effusion, we suggest that diagnostic thoracentesis may not need to be performed on both sides, unless there is a specific clinical indication.

Field surveys across various parts of the country coupled with an analysis of literature and examination of herbarium specimens revealed the natural distribution of six wild relatives of crop species in various states/union territories of India, viz., Cajanus scarabaeoides (from Lakshadweep), Cucumis javanicus (from Meghalaya), Hystrix duthiei (from Jammu & Kashmir), Luffa echinata (from Haryana) and Trichosanthes pilosa (from Andhra Pradesh), which have not been reported earlier from these states. Their descriptions, phenology, habitat and other field notes have been presented here.

Teke, Ali (Balikesir Author), We report on the operation and non-linear dynamics of a hot electron device that emits light with wavelength tunability, The device consists of p-GaAs/n-Ga-1 -xAlxAs heterojunction containing an inversion layer on the p-side, and GaAs quantum wells on the n-side. It is referred to as HELLISH-2 (Hot Electron Light Emitting and Lasing in Semiconductor Heterostructure Type 2). The device utilises hot electron longitudinal transport and the light emission is independent of the polarity of applied voltage. The wavelength of the emitted light can be tuned with applied bias from 1.50 to 1.61 eV. The operation of the device requires only two diffused in point contacts. Theoretical modelling of the device operation has been carried out and compared with the experimental results.

Teke, Ahmet (Balikesir Author), We demonstrate the operation of a novel tunable wavelength surface emitting device. The device is based on a p-GaAs and n-Ga1-xAlxAs heterojunction containing an inversion layer on the p-side, and GaAs quantum wells on the n-side, and is referred to as HELLISH-II (hot-electron light emitting and lasing in semiconductor heterojunction). The device utilizes hot-electron longitudinal transport and, therefore, light emission is independent of the polarity of the applied voltage. Because of this symmetric property, the device can perform light logic functions. The wavelength of the emitted tight can be tuned with the applied bias from GaAs band-to-band transition in the inversion layer to e1-hh1 transition in the quantum wells. The operation of the device requires only two diffused in point contacts. Therefore, a two-dimensional array of surface emitters can be fabricated very cheaply and easily. Theoretical modelling of the device operation is carried out and compared with the experimental results. An optimized structure for high-efficiency device operation, as based on our model calculations, is also proposed.

A model is presented which determines the output from a semiconductor laser as a function of the direct current (d.c.) and radio frequency (r.f.) current applied to the laser. It is shown that by adjusting these two components the output optical pulse from a laser can be shifted in time without change to the pulse shape or height. Experimental results are presented which support the model. It is suggested how these results can be used to produce a semiconductor pump-probe source, which is essential for the development of optical probing.

A novel hot electron light-emitting device is proposed which operates by the application of longitudinal electric field, i.e. in the plane of the GaAs quantum wells, which are placed next to the junction plane of an n-Ga1-xAlxAs--p-GaAs heterostructure. Application of high electric fields results in the transfer of hot electrons via tunnelling and thermionic emission, from the quantum well in the depletion region, into the GaAs inversion layer. The hot holes in the p-GaAs, initially away from the junction, then diffuse towards the junction plane to recombine with the excess hot electrons, giving rise to electroluminescence (EL) which is representative of the GaAs band-to-band emission. As the applied field is increased, a high-energy tail in the EL spectrum develops, and, photons with energies greater than the el-hhl transition energy in the quantum well are absorbed and re-emitted by the quantum well. Thus a second peak develops in the EL spectra which becomes stronger with increasing applied electric field. The device has been theoretically modelled, by solving Schrodinger and Poisson's equations self-consistently, to understand the processes leading to EL emission in the various channels.

Taxa belonging to the genus Allium are bulbous or rhizomatous with hollow or flat leaves and small delicate flowers, therefore preparing an ideal herbarium specimen is difficult. Quite often some of the characters are not well preserved while processing for herbarium specimen; occasionally they are misunderstood for characters therefore defeat the very purpose of their use as source for taxonomic study. In this paper the authors have made an attempt to provide methodology on collection and preparation of herbarium specimens of different species of Allium. Information provided herein is primarily based on the authors’ field experience and experimental and herbarium study on the genus in the Indian context. Most significant observations to be recorded in field during collecting include characters of root and bulb/rhizome, leaf, scape and flower. The paper also includes modified procedures for ‘difficult to preserve herbarium specimens’ with special notes on plant odour, flower colour and leaf colour. This can be broadly applied to taxa belonging to other bulbous groups with appropriate modification. Illustrations provided in this paper depict the representative types to facilitate better understanding by the readers.

Background Reverse engineering in systems biology entails inference of gene regulatory networks from observational data. This data typically include gene expression measurements of wild type and mutant cells in response to a given stimulus. It has been shown that when more than one type of experiment is used in the network inference process the accuracy is higher. Therefore the development of generally applicable and effective methodologies that embed multiple sources of information in a single computational framework is a worthwhile objective. Results This paper presents a new method for network inference, which uses multi-objective optimisation (MOO) to integrate multiple inference methods and experiments. We illustrate the potential of the methodology by combining ODE and correlation-based network inference procedures as well as time course and gene inactivation experiments. Here we show that our methodology is effective for a wide spectrum of data sets and method integration strategies. Conclusions The approach we present in this paper is flexible and can be used in any scenario that benefits from integration of multiple sources of information and modelling procedures in the inference process. Moreover, the application of this method to two case studies representative of bacteria and vertebrate systems has shown potential in identifying key regulators of important biological processes.

We present a review of the experimental results of the steady-state hot-electron energy and momentum relaxation for longitudinal transport in GaAs/${\mathrm{Ga}}_{1\mathrm{\ensuremath{-}}\mathit{x}}$${\mathrm{Al}}_{\mathit{x}}$As quantum wells. The results of the current work and the work reported in the literature indicate that the nonequilibrium population of LO phonons, contrary to the assumptions made in conventional theories, is randomized in K space. Therefore, the production of hot phonons not only reduces the energy relaxation rate but also enhances the momentum relaxation rate. The latter reduces the drift velocity at high fields and hence inhibits negative differential conductivity via real-space transfer or intervalley transfer. The results are compared with a comprehensive theoretical model involving nondrifting hot phonons and scattering from remote impurities and interface roughness. It is shown that hot-phonon effects increase with increasing three-dimensional carrier concentration and the agreement between the theory and the experiments carried out by three independent research groups is excellent.

The influence of a non-equilibrium population of LO phonons (hot phonons) on hot-electron energy and momentum relaxation in modulation-doped GaAs quantum wells are studied both experimentally and theoretically. The experimental results on high-field parallel transport indicate strongly that: (i) non-equilibrium phonons in GaAs quantum wells, contrary to the assumptions made in the conventional theories, are non-drifting; (ii) therefore, the production of hot phonons not only reduces the energy relaxation rate but also enhances the momentum relaxation rate; (iii) the enhancement of the momentum relaxation at high fields inhibits negative differential conductivity via real space transfer or intervalley transfer; (iv) the enhancement of the momentum relaxation rate also reduces the drift velocity at high fields, which is detrimental to the speed of the hot electron devices; (v) hot phonon effects increases with increasing 3D carrier concentration. The results are compared with a comprehensive theoretical model involving non-drifting hot phonons and scattering from remote impurities and interface roughness. The agreement between the theory and the experiments is excellent.

Hearing loss from noise exposure is a leading occupational disease, with up to 5% of the population at risk world-wide. Here, we present a novel purine-based pharmacological intervention that can ameliorate noise-induced cochlear injury. Wistar rats were exposed to narrow-band noise (8-12 kHz, 110 dB SPL, 2-24 h) to induce cochlear damage and permanent hearing loss. The selective adenosine A(1) receptor agonist, adenosine amine congener (ADAC), was administered intraperitoneally (100 microg/kg/day) at time intervals after noise exposure. Hearing thresholds were assessed using auditory brainstem responses and the hair cell loss was evaluated by quantitative histology. Free radical damage in the organ of Corti was assessed using nitrotyrosine immunohistochemistry. The treatment with ADAC after noise exposure led to a significantly greater recovery of hearing thresholds compared with controls. These results were upheld by increased survival of sensory hair cells and reduced nitrotyrosine immunoreactivity in ADAC-treated cochlea. We propose that ADAC could be a valuable treatment for noise-induced cochlear injury in instances of both acute and extended noise exposures.

Experimental results on high-field parallel transport in selectively doped GaAs/GaAlAs HEMT structures are reported. The results indicate that in lightly doped material (n=3.92*1011 cm-2), the effective rate of electron energy relaxation (EER) by LO phonons, is ( tau e) approximately 213 fs. This is about a factor of two faster than that in more heavily doped material (n=8.85*1011 cm-2). The high-field drift velocity saturates at nu ds=1.2*107 cm s-1 in the former and at nu ds=8*106 cm s-1 in the latter. The experimental results are compared with a model of high-field transport involving non-drifting hot phonon effects.

Etude des processus par lesquels les phonons optiques longitudinaux relaxent de l'energie et de la quantite de mouvement, sans interaction avec les porteurs libres. Le processus a trois phonons implique pour la determination de la duree de vie est decrit en termes de parametre d'anharmonicite. Ce parametre est analogue en mode optique du parametre de Gruneisen. D'autres processus a trois phonons du premier ordre ont des rapports negligeables pour la quantite de mouvement de relaxation

Experimental data concerning high-field parallel transport in GaAs/GaAlAs quantum well structures are reported. The results strongly suggest that (i) in modulation doped GaAs quantum wells the non-equilibrium LO phonons (hot phonons) are non-drifting, and (ii) in samples with similar 2D electron densities hot phonon effects increase with reduced dimensionality, and hence with increasing 3D electron concentration. Both observations are in excellent agreement with a recent model of high-field transport involving hot phonons.

We demonstrate the operation of a surface emitting light emitting diode. The wavelength of the emitted light can be tuned with the applied voltage. The device is based on a p‐GaAs and n‐Ga1−xAlxAs heterojunction containing an inversion layer in the p side and, GaAs quantum wells in the n side, and, is referred to as HELLISH‐II (hot electron light emitting and lasing in semiconductor heterojunction). The device utilizes hot electron longitudinal transport and, therefore, light emission is independent of the polarity of the applied voltage.

Herbarium specimens representing plant genetic resources introduced from abroad, are a distinctive component of the National Herbarium of Cultivated Plants (NHCP). These specimens represent diversity augmented in crops and wild species mostly not native to the Indian region. Herbarium specimens, bearing the unique identity number assigned to germplasm introduced into the Indian region, were screened, checked with primary and secondary data records for identity, source locality/area, and its availability as ex situ germplasm. Additional data on area of origin/diversity of species was used to delineate specimens of value in PGR and represented as cultigens, cultivars, both popular and historic, as well as local morphotypes and ecotypes of crops, as well as wild relatives of crops.

AK: L'Abhidharmakos'a de Vasubandhu, Poussin. AN: The Anguttara Nikaya. BL: Buddhist Logic, Stcherbatsky. Buddhist Philosophy: Buddhist Philosophy in India and Ceylon, Keith. Buddhist Thought: The History of Buddhist Thought, Thomas. CBN: The Conception of Buddhist Nirvana, Stcherbatsky. CCB: Central Conception of Buddhism, Stcherbatsky. Referred to also as Central Conception. DN: The Digha Nikaya. FBDC: La Formule Bouddhique Des Douze Causes, Oltramare. JPTS : Journal of the Pâli Text Society. MKV: Madhyamakavrtti (Mâdhyamikasutras de Nâgârjuna, avec la Prasannapadâ Commentaire de Candrakirti), ed., De La Vallee Poussin. MMK: Mulamadhyamaka-kirikâs, Nâgârjuna. MN: The Maijhima Nikaya. PTS: Pâli Text Society. SN: The Samyutta Nikaya. TDDC: Theorie Des Douze Causes, Poussin. UCR : University of Ceylon Review.

One of the draw-backs of the conventional light emitters appears to be that the light emission is confined to a small region of the facets of the devices1. Thus, the compatibility in generic integration technology remains a problem. The research on simple devices that emit light from the surface with good control of wavelength tunability, and which can be fabricated in large scale 2- dimensional arrays has been largely stimulated by potential applications in optical signal processing. One possible candidate for such a simple functional device is the light emitting charge injection transistor (CHINT) 2. Another light emitter, HELLISH-1 (Hot Electron Light Emission and Lasing in Semiconductor Heterostructures) has been proposed by us3–5. In this paper we present a novel surface emitting device, HELLISH-2 and demonstrate its operation with a simple model. We also report the results of our recent studies on a heavily p-n doped HELLISH-1 device.

Recently, the optic vibrations in a two-dimensional heterostructure have been described in terms of the triple hybridization of the LO and TO phonons and the interface polariton. This hybrid mode, which satisfies both mechanical and electromagnetic boundary conditions, is expected to play an important role in the high-field electron transport in these systems. For example, the creation of non-drifting hot hybrid modes would lead to a reduction of the energy relaxation rate and an enhancement of the momentum relaxation rate. The latter effect, which depends on the magnitude of the nondrift, limits the high-field electron drift velocity. This results in a suppression of the intervalley- and real-space- transfer related NDRs. A calculation of the energy and momentum relaxation rates of the hybrid modes is presented, and, their relative magnitudes are used to determine the non-drift of the hot hybrid modes.

In this paper we discuss two types of instabilities in two-dimensional semiconductor structures when the electron drift velocity, in an applied electric field, is in excess of the velocity of the acoustic modes of the system: acoustic phonons and acoustic plasmons, the latter being a feature of coupled carrier-carrier plasmas. Under suitable conditions, the piezoelectric coupling of electrons with acoustic phonons can result in an amplification of the modes, present in thermal equilibrium or deliberately injected from a transducer. This growth in acoustic flux leads to electrical non-linearities which result in the formation of acoustoelectric domains accompanied with current oscillations. These acoustoelectric domains, formed due to the bunching of electrons in the troughs of the acoustic wave, travel with the velocity of sound, and, therefore, the period of current oscillations is just the time needed for the acoustic wave to travel from one end of the crystal to the other.

Experimental results on high-field parallel transport in GaAs/GaAlAs quantum well structures are presented. The results are compared with a theoretical model of high field transport involving non-drifting hot phonons and scattering from remote impurities and interface roughness. The latter two effects contribute to the relaxation of the electron momentum. It is also shown that non-drifting hot phonons with a fmite life-time reduce the energy relaxation and enhance the momentum relaxation. The enhancement of the momentum relaxation at high fields inhibits negative differential conductivity via real space transfer or intervalley transfer. This is observed in our samples. The reduction of the drift velocity at high fields is also detrimental to the speed of many devices which operate in the hot electron regime.

In transport the creation of hot LU phonons causes a reduction in the carrier energy relaxation rate but an enhancement of the momentum relaxation rate. The magnitude of the latter determines the drift velocity attainable at high electric fields - which in turn limits the speed of devices such as FETs. How big this effect is depends on the rate of relaxation of phonon drift. Mechanisms for this relaxation are discussed and phonon-momentum relaxation rates are calculated for bulk and layered structures. Processes considered include the FrOhlich interaction with charged impurities phonon-phonon scattering and scattering at interface irregularities. We conclude that the quality of the material structure is crucial.

A novel light emitting device is proposed and demonstrated experimentally. The device consists of a GaAs quantum well placed on the n-side of the depletion region of a Ga1-xAlxAs p-n junction. Electric fields are applied parallel to the layers between two point contacts. The operation of the device is based upon the accumulation, in the quantum well, of excess hot electrons injected from the n region of the barrier via tunnelling and thermionic emission. Negative charge accumulation in the depletion region changes the potential profile, and therefore leads to a decrease in the depletion width and the potential barrier in the p-side of the junction. Hot holes then diffuse into the quantum well to recombine with the electrons. Emitted light intensity is independent of the polarity of the applied voltage. Theoretical modelling of the device is carried out by solving Schrodinger's and Poisson's equations self-consistently by incorporating tunnelling, and diffusion dynamics of the hot carriers.

Applying orthogonal in-plane electric and magnetic fields in a 2D system leads to the development of a Hall voltage across the width of the quantum well when the cyclotron orbit is greater than the well width. Tang and Butcher [1] have calculated the developed Hall voltage for a parabolic quantum well where they find that the Hall voltage is dependent on the frequency associated with the harmonic potential in the well. The limitation of this model is that it does not enable one to determine the well width dependence of the Hall Voltage, nor is it a particularly good model for a quantum well. It is also difficult to compare their model with the bulk result which would apply at large well widths. In this work we present a model calculation which considers a square quantum well and hence is able to predict the well width dependence of the Hall Voltage and compare the large well width case to the bulk result. An electro-optic probing method previously used to measure bulk Hall voltages [2] is shown to be capable of measuring the Hall 'voltage across a quantum well, and therefore can be used to confirm the prediction of the model presented here.

All of us are familiar with the saying, "nasau munir yasya matam na bhinnam — "none is a sage whose views do not differ from those of others". We find the adage in action in the highly edifying controversy regarding the momen tary, or enduring nature of things that raged between the Buddhist and the Nyaya schools of philosophy. In this paper I shall try to highlight the main points around which the wrangle has been carried on by giants on both sides. My analysis in based chiefly on a study of the doctrine of momentariness as presented by Dharmaklrti in his Hetubindu.