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Surface layer temperature inversion (SLTI), a warm layer sandwiched between surface and subsurface colder waters, has been reported to frequently occur in conjunction with barrier layers in the Bay of Bengal (BoB), with potentially commensurable impacts on climate and postmonsoon tropical cyclones. Lack of systematic measurements from the BoB in the past prevented a thorough investigation of the SLTI spatiotemporal variability, their formation mechanisms, and their contribution to the surface temperature variations. The present study benefits from the recent Research Moored Array for African-Asian-Australian Monsoon Analysis and Prediction (RAMA) buoys located in BoB along 90°E at 4°N, 8°N, 12°N, and 15°N over the 2006–2014 period. Analysis of data from these RAMA buoys indicates that SLTI forms after the summer monsoon and becomes fully developed during winter (December–February). SLTI exhibits a strong geographical dependency, with more frequent (80% times during winter) and intense inversions (amplitude, ΔT ∼ 0.7°C) occurring only in the northern BoB compared to central and southern Bay. SLTI also exhibits large interannual and intraseasonal variations, with intraseasonal amplitude significantly larger (ΔT ∼ 0.44°C) than the interannual amplitude (∼0.26°C). Heat budget analysis of the mixed layer reveals that the net surface heat loss is the most dominant process controlling the formation and maintenance of SLTI. However, there are instances of episodic advection of cold, low-saline waters over warm-saline waters leading to the formation of SLTI as in 2012–2013. Vertical processes contribute significantly to the mixed layer heat budget during winter, by warming the surface layer through entrainment and vertical diffusion.

Repeat XBT transects made at near-fortnightly intervals in the Lakshadweep Sea (southeastern Arabian Sea) and ocean data assimilation products are examined to describe the year-to-year variability in the observed near-surface thermal inversions during the winter seasons of 2002–06. Despite the existence of a large low-salinity water intrusion into the Lakshadweep Sea, there was an unusually lower number of near-surface thermal inversions during the winter 2005/06 compared to the other winters. The possible causative mechanisms are examined. During the summer monsoon of 2005 and the following winter season, unusually heavy rainfall occurred over the southwestern Bay of Bengal and the Lakshadweep Sea compared to other years in the study. Furthermore, during the winter of 2005, both the East India Coastal Current and the Winter Monsoon Current were stronger compared to the other years, transporting larger quantities of low salinity waters from the Bay of Bengal into the Lakshadweep Sea where a relatively cooler near-surface thermal regime persisted owing to prolonged upwelling until November 2005. In addition, the observed local surface wind field was relatively stronger, and the net surface heat gain to the ocean was weaker over the Lakshadweep Sea during the postmonsoon season of 2005. Thus, in winter 2005/06, the combination of prolonged upwelling and stronger surface wind field resulting in anomalous net surface heat loss caused weaker secondary warming of the near-surface waters in the Lakshadweep Sea. This led to a weaker horizontal sea surface temperature (SST) gradient between the Lakshadweep Sea and the intruding Bay of Bengal waters and, hence, a reduced number of thermal inversions compared to other winters despite the presence of stronger vertical haline stratification.

A new species of Dubyaea (Asteraceae), D. forrestii Mamgain & R.R.Rao, from the Burma/China border is described, illustrated and compared with D. atropurpurea. The affinities of the new species to Dubyaea atropurpurea are discussed.

The formation mechanisms of the barrier layer (BL) and its seasonal variability in the Arabian Sea (AS) are studied using a comprehensive dataset of temperature and salinity profiles from Argo and other archives for the AS. Relatively thick BL of 20–60 m with large spatial extent is found in the central-southwestern AS (CSWAS), the convergence zone of the monsoon wind, during the peak summer monsoon (July–August) and in the southeastern AS (SEAS) and northeastern AS (NEAS) during the winter (January–February). Although the BL in the SEAS has been reported before, the observed thick BL in the central-southwestern AS during the peak summer monsoon and in the northeastern AS during late winter are the new findings of this study. The seasonal variability of BL thickness (BLT) is closely related to the processes that occur during summer and winter monsoons. During both seasons, the Ekman processes and the distribution of low-salinity waters in the surface layer show a dominant influence on the observed BLT distributions. In addition, Kelvin and Rossby waves also modulate the observed BL thickness in the AS. The relatively low salinity surface water overlying the Arabian Sea high-salinity water (ASHSW) provides an ideal ground for strong haline stratification in the CSWAS (during summer monsoon) and in NEAS (during winter monsoon). During summer, northward advection of equatorial low-salinity water by the Somali Current and the offshore advection of low-salinity water from the upwelling region facilitate the salinity stratification that is necessary to develop the observed BL in the CSWAS. In the SEAS, during winter, the winter monsoon current (WMC) carries less saline water over relatively high salinity ambient water to form the observed BL there. The winter West India Coastal Current (WICC) transports the low-salinity water from the SEAS to the NEAS, where it lies over the subducted ASHSW leading to strong haline stratification. Ekman pumping together with the downwelling Kelvin wave in the NEAS deepen the thermocline to cause the observed thick BL in the NEAS.

The association properties of Pu with aquatic humic substances in a 0.01M NaClO4 solution at pH 6–8 were studied on the basis of molecular size distribution. Seven humic substances were isolated from river water and groundwaters using XAD extraction technique. They were used for comparing their effects on the association of Pu. In the presence of humic acid, the dominant molecular size of Pu was 100–30 kDa. In the presence of fulvic acid, Pu exhibited three dominant molecular sizes: 30–10 kDa, 30–5 kDa, and less than 5 kDa. The association of Pu-humus complexes might be controlled by the molecular size distribution of humic substances and characteristics of their respective size fractions.

The Andaman coral reef region experienced mass bleaching events during 1998 and 2010. The purpose of this study is to investigate the role of the El Nino in the coral reef bleaching events of the Andaman region. Both Nino 3.4 and 3 indices were examined to find out the relationship between the mass bleaching events and El Nino, and correlated with sea surface temperature (SST) anomalies in the Andaman Sea. The result shows that abnormal warming and mass bleaching events in the Andaman Sea were seen only during strong El Nino years of 1997–1998 and 2009–2010. The Andaman Sea SST was more elevated and associated with El Nino Modoki (central Pacific El Nino) than conventional El Nino (eastern Pacific El Nino) occurrences. It is suggested that the development of hot spot patterns around the Andaman Islands during May 1998 and April–May 2010 may be attributed to zonal shifts in the Walker circulation driven by El Nino during the corresponding period.

A subset of the newly published salinity and temperature climatologies of the global ocean is assembled to examine the observed seasonal variability of the near-surface salinity field of the tropical Indian Ocean. The role of vertical haline stratification in the near-surface layers on the manifestation of the barrier layer thickness in the new climatology is addressed. The warm pool of the tropical Indian Ocean is characterized to identify the geographic regions where the near-surface haline stratification and the warm pool core co-exist. Among the three regions within the warm pool of the tropical Indian Ocean, viz., southeastern Arabian Sea, southwestern Bay of Bengal and eastern equatorial Indian Ocean, a strong coupling between the near-surface haline stratification and the subsequent evolution of the warm pool core is most prominently seen only in the southeastern Arabian Sea. The observed year to year co-variability of the near-surface low salinity pool and the warm pool core in the southeastern Arabian Sea is examined.

Observed short term (few days to few weeks) variability of mixed layer depth (MLD) and temperature (MLT) at selected locations in the Arabian Sea during pre and summer monsoon seasons is discussed. In the Arabian Sea, pre monsoon season is generally characterized by fair weather conditions with occasional thunder squalls. In the eastern Arabian Sea, SST is above 30° C, which is assumed to be the part of the Indian Ocean warm pool, and is characterized by the diurnal range of about 1.5° C. During the monsoon season, maximum cooling (>l° C) and deepening (5075 m) of the mixed layer is noticed in the central Arabian Sea during the onset phase. On the contrary, the mixed layer shoals in the coastal zones due to upwelling. Miller's one dimensional mixed layer model is used to simulate the observed mixed layer variability. The model simulated MLT and MLD variations reasonably well on a synoptic scale. Whenever advective processes (horizontal and vertical) and large amplitude waves dominate, significant departures are noticed between the observed and simulated values.

Floristic Composition of the Weed Flora, Seasonal Variation and Phenology of Some Weeds of Agriculture Lands in Khasi Hills, Meghalaya

Diversity of Indian Flora

Observations on The Reproductive Biology of Endangered Eremostachys superba (Labiatae)

Contributions to the Aerobilogy of Shillong I Studies on the Seasonal Varation of Atmospheric Pollen and Fungal Spores

The Genus Eupatorium Linn (Asteraceae) in North-East India

The present paper deals with the different life form categories and biological spectrum of the flora of Tons Valley in Garhwal Himalaya. It includes Phanerophytes (29.06%), Nano- phanerophytes (6.47%), Chamaephytes (22.19%), Hemicryptophytes (2.11%), Geophytes (2.64%), Hydrophytes and Helophytes (8.58%), Therophytes (17.83%), Lianas (10.43%), and Epiphytes (O.66%). The comparison with Raunkiaer's normal spectrum depicts 'Hydro- Chamaephytic Phytoclimate.'

Underwater gliders measure high-resolution spatiotemporal oceanographic data. In April 2014, the National Institute of Ocean Technology, Chennai operated an underwater glider ‘Barathi’, for 127 days for observation of Bay of Bengal (BoB). In this article we present the effectiveness of the glider Barathi for high resolution temporal sampling of the surface layer in the central BoB for studying variation of temperature, salinity and density structures and acoustic characteristics on 26–27 May 2014. The results showed ‘afternoon effect’ on acoustic characteristics and formation of secondary sound channel. Our data set is strongly correlated (coefficient of determination r 2 > 0.96) with data from a nearby Array for real-time geostrophic Oceanography (Argo) float.

The observed nature of buildup and collapse of warm pool in the eastern Arabian Sea and the Bay of Bengal is examined with help of sea surface temperature (SST) data collected by NIOT buoy network during the period 1998–2008. During the buildup phase, the SSTs showed a progressive increase in both the eastern Arabian Sea and the Bay of Bengal. During this phase, the amplitudes of the diurnal oscillations of SST are relatively larger in the Bay of Bengal compared to those in the Arabian Sea. During the collapse phase, the SST cooling was dramatic in the eastern Arabian Sean caused by the monsoon onset vortex. Relatively larger amplitude intraseasonal oscillations are seen only in the Bay of Bengal and off the southwest coast of India during the collapse phase.

The diversity in vegetation and flora of Tons Valley in Garhwal Himalaya has been extensively studied during 1994-98. On the whole 761 species of phanerogams referable to 480 genera and 132 families could be recognised in the flora of Tons Valley. The vegetation predominantly is of forest communities which is evergreen type intermixed with deciduous species. The vegetational diversity of the area is discussed broadly under: forest vegetation, seasonal vegetation, and aquatic and marshy vegetation. An analysis of the phytogeographical affinities of the flora shows that the flora of Tons Valley has affinities with surrounding regions. There is predominance of Indian, Indo-Malayan, African-Asiatic-Australian and Palaeotropical elements in the flora. Euro-Siberian and Sino-Jananese species have also found their ways to the Tons Valley.

The observed short term variability in the current field of the upper layers at selected locations in the Arabian Sea is examined utilising the available short (1-2 weeks) time series of moored currentmeter records obtained from former USSR stationary ship polygons during MONSOON-77 and MONEX-79 field experiments. Supplementary time series data sets on surface wind, sub-surface temperature and salinity were also made use of to explain the observed structure and variability of current field, in the upper 2OOm water column. The thermal regime in the central Arabian Sea showed cooling and deepening of the surface mixed layer with the onset and progress of the summer monsoon during MONSOON- 77 while the corresponding variability was marginal in the western and south-central Arabian Sea during pre-onset regime of MONEX-79, The Ekman balance appeared to be limited to the mixed layer, only during pre-onset regime of MONSOON-77 and was absent during pre-onset and onset regimes of MONEX-79 suggesting the importance of internal ocean dynamics influencing the current field. Most of the current records showed rich structure with superposed oscillations extending over the entire 200m water column. During progress regime of MONSOON-77 and at the equatorial station during pre-onset regime of MONEX-79. dramatic reduction in the current strength is noticed from mixed layer to thermocline due to differences in the eddy viscosity. During MONEX-79, a strong subsurface core of southerly flow ( -100 cm/s) was noticed at the equator (49°E) even before the onset of monsoon. The vector time series of current-meter records subjected to rotary spectral analysis showed inertial oscillations in the flow regime more prominently during MONSOON-77 as compared to MONEX-79. R.R. RAO. K. V. SANIL KUMAR123@gmail.com and BASIL MATHEW123@gmail.com

Canadian deuterium uranium (CANDU) pressurized heavy-water reactors produce 14C by neutron activation of trace quantities of nitrogen in annular gas and reactor components (14N(n,p)14C), and from 17O in the heavy water moderator by (17O(n,α)14C). The radiocarbon produced in the moderator is removed on ion exchange resins incorporated in the water purification systems; however, a much smaller gaseous portion is vented from reactor stacks at activity levels considerably below 1% of permissible derived emission limits. Early measurements of the carbon speciation indicated that >90% of the 14C emitted was in the form of CO2. We conducted surveys of the atmospheric dispersion of 14CO2 at the Chalk River Laboratories and at the Pickering Nuclear Generating Station. We analyzed air, vegetation, soils and tree rings to add to the historical record of 14C emissions at these sites, and to gain an understanding of the relative importance of the various carbon pools that act as sources/sinks within the total 14C budget. Better model parameters than those currently available for calculating the dose to the critical group can be obtained in this manner. Global dose estimates may require the development of techniques for estimating emissions occurring outside the growing season.

A pilot project was initiated to study the feasibility of preparing milk as a candidate reference material for 14C near environmental levels. Two materials, MK-B at natural level of 14C and MK-C4 at an elevated level, have been prepared from pasteurized 2% dairy milk. MK-C4 was spiked with an appropriate amount of 14C-methylated casein tracer to achieve the elevated level. Several samples from MK-B and MK-C4 have been analyzed to test the homogeneity of these materials for the distribution of 14C. The samples were combusted in oxygen under 20 atmospheres pressure using a Parr bomb. The 14C concentrations were determined by liquid scintillation counting using Carbo-Sorb/Permafluor E+ cocktail. The results indicate that these materials are homogeneous with respect to 14C concentration even in sub-sample sizes of 0.25 g of the freeze-dried material. The precision of our 14C measurements, as expressed by the % relative standard deviation, is within 5%. The accuracy has been tested by analyzing replicate samples of the IAEA 14C quality assurance materials, C-3 (cellulose) and C-6 (ANU sucrose) and found to be within 3%. The lower limits of detection are 0.08, 0.05 and 0.02 Bq.g−1 of carbon for 20 ml of liquid scintillation mixture (Carbo-Sorb/Permafluor E+ = ∼0.67) loaded with up to 0.4 g of carbon from the sample and counted for 3 cycles of 60, 180 and 1000 min each, respectively. Our measurements of 14C specific activities of MK-B and MK-C4 are 0.26±0.01 and 15.3±0.4 Bq.g−1 of carbon, respectively.

Epithermal instrumental neutron activation analysis (EINAA) methods have been optimized and applied to several biological reference materials and selected food items for the determination of iodine. The method involves irradiation of the samples for different periods in epi-cadmium and/or epi-boron flux of the Dalhousie University SLOWPOKE-2 reactor and direct counting without any pre-treatment on a 25-cm3 hyperpure Ge detector. The 443 keV photopeak of 128I is used for assaying the iodine content. Precision of measurements, expressed as the relative standard deviation, is 10–15% at 200–500 ppb and 3–12% at 500–6000 ppb levels of iodine. Accuracy of iodine measurements is within 5%. The detection limits for iodine in several biological materials with cadmium and boron, either alone or a combination of the two, as thermal neutron shields have been found to vary between 0.1 and 0.4 mg · kg−1 for different periods of irradiation, decay and counting. The results suggest that the EINAA methods can be successfully applied to biological materials for routine analysis of iodine at levels higher than 200 ppb.

The volatile oil of the leaves of Pogostemon heyneanus Benth. (Lamiaceae) was analyzed by GC and GC-MS. Twenty-six components representing 96.0% of the oil were identified. The major components of the oil were acetophenone (51.0%), β-pinene (5.3%), ( E)-nerolidol (5.4%), and patchouli alcohol (14.0%). Comparison of the compositions of the oils of P. heyneanus and P. cablin (Blanco) Benth. (Patchouli oil) showed wide variation between them. Though 13 sesquiterpenes and oxygenated sesquiterpenes were detected in both oils, their concentrations in the oils differed widely. Acetophenone, benzoyl acetone and ( E)-nerolidol present in the oil of P. heyneanus were not detected in patchouli oil.

Residues of polychlorinated biphenyls (PCBs) and organochlorine pesticides were determined in several species of commercial fish from the Great Lakes and compared to the total organic chlorine determined by neutron activation analysis. The mean organochlorine contents ranged from 44 to 138 ppm (lipid basis) and were 5 to 72 times higher than the contents of PCBs and organochlorine pesticides. Marine fish also contained a large proportion of unidentified organic chlorine. The unknown material in the Great Lakes fish was found to chromatograph with the high molecular weight lipid fraction by gel permeation chromatography.

A preliminary study was conducted to know the age, sex distribution and clinical pattern of cutaneous leishmaniasis (CL) in a remote hilly area, Faifa, Gizan situated in the South West region of the Kingdom of Saudi Arabia. C L accounted for nearly 5% of the new outpatient attendance in the study period (1988-90) of 20 months. Out of the 140 new patients who formed the study group, 82 were males (58.57%) and 58 females (41.43%) in the age range of 9 months to 60 years. Ninety two patients were children (65.71%) below 15 years. including 58 boys and 34 girls and CL is a major public health problem in children of this area. The fact that out of 140 affected individuals, 134 were local Saudis and 6 non-Saudis reveals the autochthonous nature of the disease in this region. The clinical spectrum included dry crusted ulcers, erythematous indurated plaques, nodules, papules, and oozing shallow ulcers. The lesions were distributed mostly on face and extremities. Response to pentostam (Sodium stibogluconate) was highly satisfactory.

Lincomycin is chemically distinct from all other available antibiotics except its semi-synthetic derivative clindamycin. Though it has been in the market for over three decades, there were not many clinical studies in India. This study has been undertaken to know its efficacy against Staphylococcus aureus, commonest organism of pyodermas in children. Material was taken from the lesions of 100 fresh cases of various types of pyodermas in children and studied by Gram stain and in 50% human blood agar and nutrient agar according to standard methods. The staphylococci thus isolated were tested for linocomycin susceptibility by using the disc diffusion technique. Lincomycin was given to all these children in a daily dose of 30 mg/kg 5 - 10 days. Treatment failure was defined as persistence of lesions after 10 days of treatment. 75% strains of staphylococci were susceptible to lincomycin in vitro and 95% of the patients responded to 5-10 days treatment. Five out of 100 children did not respond to treatment even after 10 days. No case of relapse was noticed among these 95 children for a period of 2 weeks. No side effects were observed and the drug was very well tolerated. Being highly effective and least toxic linomycin deserves a place in the antimicrobial arsenal of the modern dermatologists.

International audience; The southeastern Arabian Sea (SEAS), located in the Indian Ocean warm pool, is a key-region of the regional climate system. It is suspected to play an important role in the dynamics of the Asian summer monsoon system. The present study reports the salient features derived from a newly harvested observational dataset consisting of repeated fortnightly XBT transects in the SEAS over the period 2002-2008. The fortnightly resolution of such a multi-year record duration is unprecedented in this part of the world ocean and provides a unique opportunity to examine the observed variability of the near-surface thermal structure over a wide spectrum, from intra-seasonal to interannual timescales. We find that most of the variability is trapped in the thermocline, taking the form of upwelling and downwelling motions of the thermal stratification. The seasonal variations are consistent with past studies and confirm the role of the monsoonal wind forcing through linear baroclinic waves (coastally-trapped Kelvin and planetary Rossby waves). Sub-seasonal variability takes the form of anomalous events lasting a few weeks to a few months and occurs at two preferred timescales: in the 30-110 day band, within the frequency domain of the Madden-Julian oscillation and in the 120-180 day band. While this sub-seasonal variability appears fairly barotropic in the offshore region, the sign of the anomaly in the upper thermocline is opposite to that in its lower part on many occasions along the coast. Our dataset also reveals relatively large interannual temperature variations of about 1 °C from 50 to 200 m depth that reflect a considerable year-to-year variability of the magnitude of both upwelling and downwelling events. This study clearly demonstrates the necessity for sustained long-term temperature measurements in the SEAS.

Superconducting thin films of Y1Ba2Cu3 O7 −x have been deposited on (100) Y-ZrO2 substrates by pulsed excimer laser ablation from anunreacted mixture of Y2O3, BaCO3 and CuO. The films deposited at substrate temperature of 680°C and oxygen partial pressure of 200 mtorr were found to be superconducting with zero resistive transition temperature of 89 K and critical current density of over 3 × 105 A/cm2 at 77 K. These results are compared with those obtained by laser ablation from a sintered superconducting pellet.

The intra-seasonal variability observed in the salinity field of the upper layers at a few locations in the east central Arabian Sea and the northern Bay of Bengal during the summer monsoon seasons of 1977 and 1979 is documented with the aid of short time series (1–2 weeks) of salinity measurements made from USSR and Indian ships deployed during MONSOON-77 (1977) and MONEX-79 (1979) field experiments. In the Arabian Sea a typical subsurface maxima observed beneath the mixed layer base either disappeared or considerably weakened due to strong vertical mixing caused by the monsoonal forcing. In the northern Bay of Bengal the salinity variability in the top 30 m water column was rapid and appeared to be influenced by large amounts of fresh water from rain and probably from the major adjoining rivers. Some simple diagnostic calculations are presented to assess the relative importance of various processes which control the observed salinity variability.

The observed short term. variability in .the current field of the upper layers of the northern Bay of Bengal IS examined utilizing the available time series data sets of current meter records obtained from mooring lines deployed from USSR stationary ship polygons during MONSOON-77 and MONEX-79 field experiments. Supplementary time series data sets on the vertical profiles of temperature and salinity in addition to surface winds were also made use of to describe the observed variability and structure of the horizontal velocity in the upper 200 m water column. Although the thermal regime appeared to be homogeneous within both the observational arrays considerable differences were noticed in the salinity and current regimes. The strong vertical stratification which is variable in the northern Bay of Bengal appeared to have Influenced the observed upper oceanic flow regime. Evidence for Ekman type of balance was rather weak suggesting the importance of baroclinic and river driven circulation modes. A clockwise eddy type of circulation was evident only during MONEX-79 but not during MONSOON- 77. The vector time series of current meter records were subjected to rotary spectral analysis to identity the periodicities of energetic oscillations and to infer the nature of circulation. Three to five-day oscillations in the flow regime were noticed during MONEX- 79.

[1] Repeat near-fortnightly expendable bathythermograph (XBT) transects made along Kochi-Kavaratti (KK) shipping lane in the Lakshadweep Sea (LS) during 2002–2006 are examined to describe the observed year-to-year variability of upwelling during summer monsoon season (SMS). Among all the years, the upwelling characterized by up-sloping of 25°C isotherm is relatively weaker and persisted until November during SMS of 2005 and is stronger during the SMS of 2002. As a result of prolonged upwelling, the sea surface temperature has shown cooling extending into the postmonsoon season. The estimated marine pelagic fish landings along the southwest coast of India (SWCI) have also shown increase until December. The governing mechanisms both in terms of local and remote forcings are examined to explain the observed anomalous upwelling during SMS of 2005. The equatorward alongshore wind stress (WS) along the KK XBT transect persisted in a transient manner beyond September only during SMS of 2005. The westerly wind bursts over the equator during the winter of 2004–2005 are both short-lived and relatively weaker triggering weaker upwelling Kelvin waves that propagated into LS in the following SMS of 2005. The observed distribution of negative sea surface height anomaly in the LS is relatively weaker during the SMS of 2005 and lasted longer. The correlation analysis suggests that the local alongshore WS off the SWCI and the remote forcing from the southern coast of Sri Lanka has greater influence on the observed interannual variability of upwelling in the LS when compared to the remote forcing from the equator.

The intra-seasonal variability noticed in the thermohaline characteristics in the upper layers of the Arabian Sea during the summer monsoon season of 1973 is described with the aid of repeat transects made by USSR and Indian ships along some typical zonal and meridional sections covered during the pre and post onset regimes of Indo-Soviet Monsoon Experiment (ISMEX-73). An attempt is made to compare this observed variability during the summer monsoon seasons of 1971, 1972 and 1973 with the limited available data sets. The observed short-term variability during the pre and post onset regimes at one station (60OE) on the equator and another station (18O N, 67O E) in the northeastern Arabian Sea is described and discussed to highlight the uneven response of the Arabian s\Sea in its spatial domain to the variable seasonal monsoonal forcing.

Temperature data collected in the upper layers of the central Arabian Sea before and after the onset of the summer monsoon during the three monsoon experiments ISMEX-73 (1973), MONSOON-77 (1977) and MONEX-79 (1979) from stationary ships are made use of to document the observed variability in the upper ocean thermal structure with the onset of the monsoon. Cooling and deepening of the mixed layer and warming below the layer were found to be of unequal magnitudes under the influence of onset vortex during these three years. Similar differences were also noticed in the profiles of vertical thermal gradient. Absence of a secondary maximum in the vertical thermal gradient during 1973 suggests a weak summer monsoonal forcing during 1972, which was viewed as a global drought year. Large differences were noticed in the changes of accumulative heat content between 1973 and 1979 which were good and bad monsoon years respectively.

A cyclic instrumental neutron activation analysis method has been used to calculate sampling constants and to evaluate homogeneity for Se in five biological reference and certified reference materials, namely NRC lobster hepatopancreas (RM TORT-1), IAEA horse kidney (RM-H8), and NIST bovine liver (SRM-1577a), oyster tissue (SRM-1566) and mixed diet (RM-8431). The between-weight-range heterogeneity has been observed to be no greater than the within-weight-range heterogeneity. The subsampling standard deviation (S s) has been found to be less than the measurement standard deviation (S m) for H-8 (>5 mg sample) and TORT-1 (>50 mg). For 1577a, S s is almost equal to S m; while S s is 2–3 times higher than S m for the other two materials. The sampling constants varied between 0.04 and 3.0 g for four materials while the mixed diet had a value of 31 g.

Background: Kaposi`s varicelliform eruption (KVE) represents widespread cutaneous herpes simplex virus (HSV) infection in patients with preexisting dermatoses. Occasionally, this infection can present as a nosocomial infection in skin wards, if adequate bed-spacing and barrier nursing methods are not followed. We are reporting five cases of KVE; four cases acquired the infection in a makeshift ward after admission of the first case in May 2005, due to the renovation work of the regular skin ward. Aim: The purpose of this study is to create clinical awareness about this uncommon dermatologic entity and to stress upon the importance of bed-spacing and barrier nursing in skin wards. Methods: Five cases of KVE, three females and two males with different primary dermatoses (pemphigus foliaceus - one, pemphigus vulgaris - two, paraneoplastic pemphigus - one and toxic epidemal necrolysis - one) were included in this study. Diagnosis was made clinically and supported with Tzanck smear and HSV serology. All the cases were treated with oral acyclovir. Results: Four out of five cases of KVE recovered with treatment, one case of extensive pemphigus vulgaris with KVE succumbed to death. Conclusion: Mini outbreaks of KVE can occur in skin wards with inadequate bed-spacing and overcrowding of patients. Therefore adequate bed-spacing, barrier nursing and isolation of suspected cases are mandatory to prevent such life-threatening infections.

[1] The observed formation of barrier layer (BL) and the seasonal variability of BL thickness (BLT) in the Bay of Bengal are examined utilizing the most comprehensive data set. Thick BL (∼40 m) first appears in the coastal region of the northeastern bay in June and spreads westward as the summer monsoon progresses. Along the east coast of India the BL formation and its variability are controlled by the East India Coastal Current (EICC). Thick BL (∼50 m) appears along the east coast of India in November when the EICC flows equatorward and gets spatially organized by December. By January it weakens when the EICC reverses. The mature phase of BLT, both in amplitude (∼60 m) and in spatial extent occurs during February, when the Subtropical Anticyclonic Gyre (SAG) is well established in the bay. During both the summer and winter monsoon seasons the surface circulation and the redistribution of low saline waters show a dominant influence on the observed BLT distribution. Other processes such as Ekman pumping and propagating Rossby waves forced by the propagating Kelvin waves along the eastern boundary also contribute significantly in modulating its variability. The annual mode of BLT shows maxima during November–December, whereas the semiannual mode peaks during February–March and August–September. The peak in February–March is attributed to the interior Ekman pumping and the associated convergence in the central bay, whereas the peak during August–September is due to the westward propagating downwelling Rossby waves from the eastern boundary.

[1] The sea surface salinity (SSS) of the Lakshadweep Sea (LS) shows large seasonal variability due to horizontal advection of low (high) salinity waters from south (north) during winter (summer) monsoon. The measurements made in the LS during the Arabian Sea Monsoon Experiment (ARMEX), have shown a dramatic drop of 3.4 PSU in the SSS during the winter following an active (2003) monsoon that is double that of the drop of 1.7 PSU observed during the winter following a weak (2002) monsoon. The resultant near-surface thermal inversions also have shown large differences in the life cycle and depth of occurrence between these two winters.

Summary Serum cholesterol and its subfractions were estimated in 23 patients on thiazide diuretics, for treatment of mild hypertension, for at least 30 months. The results were compared with those obtained in a matched set of 25 untreated mild hypertensives. It was found that while there was no difference in the level of total cholesterol, the LDL-cholesterol was significantly lower and HDL-cholesterol significantly higher in the treated group. It was also found that the total:LDL-cholesterol ratio was more in the treated group and the total:HDL-cholesterol ratio was less in the treated group. These findings suggest that coronary risk attributable to cholesterol and its subfractions does not seem to operate in long term thiazide treated patients.

Powders of pure beta-tricalcium phosphate (beta-TCP), hydroxyapatite (HAP) and a biphasic composite mixture of HAP+beta-TCP were prepared by solid state reaction between two commercially available calcium-based precursors namely, tricalcium phosphate (TCP) and calcium hydroxide (Ca(OH)2). These reactants mixed in the molar ratios ranging from 3 : 0 to 3 : 4 (designated T0 to T4) in deionized water, milled and slip-cast into discs were heat treated in the temperature range of 600 degrees C to 1250 degrees C. The products formed were characterized by X-ray diffraction (XRD) and i.r. spectroscopic techniques for identification of phases formed and functional groups present in them. While tricalcium phosphate and calcium hydroxide taken in the molar ratio of 3 : 2 and 3 : 3 resulted in pure HAP when heat treated at 1000 degrees C for 8 h, the 3 : 1 and 3 : 1.5 molar ratio compositions resulted in a biphasic mixture of HAP+beta-TCP for similar heat treatments. Heat treatment of 3 : 4 molar ratio composition of tricalcium phosphate and calcium hydroxide at 1000 degrees C yielded HAP with free CaO as the secondary phase. Products of heat treatment at higher temperatures (1150 and 1250 degrees C) for even shorter duration (2 h) while not differing from the products obtained from T0 and T2 cases at 1000 degrees C (pure beta-TCP and pure HAP), change in the case of T1, T1.5, T3 and T4 to products with lesser percentages of HAP containing beta-TCP (in the case of T1 and T1.5) or CaO (in the case of T3 and T4) as the secondary phase.

The first accepted report of a novel human, slow virus disease belonging to "lentivirus" known as acquired immunodeficiency syndrome can be traced to reports of June 1981. HIV-1 and HIV-2 were later found over the period 1984-86 to be unequivocally associated with AIDS. They are two serologically distinct viruses belonging to the same family with the unique properties of integration and latency in the host cell genome and the presence of reverse transcriptase. Typical of all retroviruses, the HIV genome comprises three genes governing the synthesis of all core proteins, replication protein encoding, and envelope proteins. HIV uses the CD4 antigen on T-helper cells, and about 40% of blood monocytes and tissue macrophages as a cell surface receptor. HIV may, however, also infect cells which contain no CD4. Macrophages serve as the main reservoir of HIV and may carry the virus to different organs. Very recently a rare type of white blood cell called the dendritic cell has been found to allow for direct infection by HIV during sexual intercourse. These cells are prominently present in the anal and vaginal mucosa. The authors discuss facts and figures on the HIV epidemic, the Indian scenario, classification of the clinical spectrum, the enzyme immunoassay HIV testing format, Western blot, immunofluorescence antibody, HIV culture, flow cytometry, radio immuno precipitation assay, and the detection of HIV DNA. Significant advances have been made over the last ten years in understanding the pathogenesis of HIV infection and accurately diagnosing infected individuals, with recombinant technology, polymerase chain reaction, and the construction of synthetic hybrid virus rapidly becoming part of routine diagnostics. More sensitive, specific, and rapid techniques are, however, needed for the early diagnosis and management of AIDS cases. The need for more ideal antibody incorporating both regulatory and structural proteins of the virion, preferably manufactured using recombinant or peptide synthesis technique, with high purity and concentrations must be viewed seriously.

The bacteriology of brain abscess is complex--both aerobic and anaerobic organisms are involved, and their incidence varies from centre to centre. In this study of 50 consecutive cases of brain abscess, the value of both modern imaging techniques and the time-honoured Gram's stain was demonstrated. The Gram's stain showed organisms in 41 cases (82%) and culture was positive in 44 cases (88%). Thirty cultures yielded pure aerobic growth: Staphylococcus aureus, beta-haemolytic streptococci and Proteus spp. were predominant. Five cases gave mixed aerobic cultures, and in seven cases anaerobes were isolated. Of these, three showed a mixed aerobic and anaerobic flora. Mycobacterium tuberculosis was cultured from one of the samples, which had shown acid-fast bacilli on direct smear. M. fortuitum was cultured from one sample, although no organisms were seen in the gram-stained preparation.

Vanadium(IV) and (V) can be quantitatively extracted with 0.2 mol/l Amberlite LA-2 in xylene at pH 3.0 from 0.02 mol/l malonic acid, stripped with 0.5 mol/l hydrochloric acid, and determined spectrophotometrically. Five other liquid anion exchangers (Amberlite LA-1, Primene JM-T, Aliquat 336S, TOA and TIOA) were examined as possible extractants. The extraction of vanadium(IV) was found to be quantitative only with Amberlite LA-2, while that of vanadium(V) was quantitative with Amberlite LA-1 and LA-2, Primene JM-T and Aliquat 336S. Eight common solvents were tested as diluents; of these hexane, cyclohexane, benzene, and xylene were found to be satisfactory. Vanadium was separated from elements that do not form anionic complexes with malonic acid by selective extraction, from those that form weak complexes by washing the organic extract with water, and from metals that form strong malonato complexes by selective stripping with hydrochloric, nitric, or sulphuric acid. The method has been applied to the determination of vanadium in steel, coal fly ash and fuel oil. The precision of measurement is within +/- 5% and the detection limit of the method for vanadium is 0.5 mg/kg.

Serum Adenosine Deaminase (ADA) enzyme levels were estimated in 61 patients with symptoms and signs suggestive of Pulmonary Tuberculosis and correlated with "Gold standards" such as smear positivity of sputum for Acid Fast bacilli, Tuberculin skin testing and Radiological evidence. The mean ADA levels in smear and Tuberculin negative patients was 13.13 +/- 5.97 u/L, while in those with smear and/or strongly positive Tuberculin reaction, the mean levels of ADA were 33.52 +/- 15.22 u/L. The mean serum ADA levels in 25 healthy voluntary donors with no evidence of active or old Tuberculous lesion, were found to be 16.5 +/- 3.18 u/L. The specificity, sensitivity, positive predictive value and negative predictive value of the test was found to be 87%, 71%, 90% and 66.5% respectively. The results conclude that the serum ADA value is sufficiently useful in identifying those patients in whom the diagnosis of Pulmonary Tuberculosis should be actively considered.

Epidemiological surveillance of Hepatitis B surface antigen in the city of Hyderabad at our Institute shows that the incidence of HBsAg is considerably high among the general population. In a comparative evaluation of the two techniques used, RPHA and ELISA, the latter emerged as a reliable one with high specificity and sensitivity. Screening of all blood samples by ELISA is imperative for uniform reporting of the incidence. Non risk groups like voluntary blood donors, cardiac patients serve as potential reservoirs of HBV infection.

A case of necrotizing fasciitis of the anterior abdominal wall caused by the zygomycete Apophysomyces elegans in a healthy male following inguinal herniorrhaphy is reported. The portal of entry of the fungus into the incised skin and subcutaneous tissues was probably through either contaminated surgical sutures or postoperative surgical dressings. Broad, aseptate fungal hyphae were seen in the necrosed tissues with an associated necrotizing vasculitis. Extensive tissue debridements and a low dose of amphotericin B were not successful in controlling the rapid invasion of the tissues by the fungus.