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Seismotectonic and the geodynamical processes between India and Antarctica are essential. During the initial 25 years of Indian expeditions, India's National Geophysical Research Institute (NGRI) launched a GPS-Geodesy programme by establishing a permanent GPS tracking station and a state-of-the-art Digital Broad Band Seismological Observatory Maitri during 1997. Both these stations have been continuously operational. It addresses the crustal deformation in the south of the Indian peninsula, the driving mechanisms, and the response of the Indian Ocean lithosphere bringing a deep understanding of the causes of the accumulation processes of strain in the Indian Ocean and the northward movement of the Indian plate.

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.

The observed variability of zonal currents (ZC) at the Equator, 90°E shows a strong seasonal cycle in the near-surface 40–350 m water column with periodic east–west reversals most pronounced at semiannual frequency. Superposed on this, a strong intraseasonal variability of 30–90 day periodicity is also prominently seen in the near-surface layer (40–80 m) almost throughout the year with the only exception of February–March. An eastward flowing equatorial undercurrent (EUC) is present in the depth range of 80–160 m during March–April and October–November. The observed intraseasonal variability in the near-surface layer is primarily determined by the equatorial zonal westerly wind bursts (WWBs) through local frictional coupling between the zonal flow in the surface layer and surface zonal winds and shows large interannual variability. The eastward flowing EUC maintained by the ZPG set up by the east–west slope of the thermocline remotely controlled by the zonal wind (ZW) and zonally propagating wave fields also shows significant interannual variability. This observed variability on interannual time scales appears to be controlled by the corresponding variability in the alongshore winds off the Somalia coast during the preceding boreal winter, the ZW field along the equator, and the associated zonally propagating Kelvin and Rossby waves. The salinity induced vertical stratification observed in the near-surface layer through barrier layer thickness (BLT) effects also shows a significant influence on the ZC field on intraseasonal time scale. Interestingly, among all the 8 years (2001–2008), relatively weaker annual cycle is seen in both ZC in the 40–350 m water column and boreal spring sea surface temperature (SST) only during 2001 and 2008 along the equator caused through propagating wave dynamics.

We studied the magnetic ordering of thin films and bulk crystals of rutile RuO_{2} using resonant x-ray scattering across the Ru L_{2} absorption edge. Combining polarization analysis and azimuthal angle dependence of the magnetic Bragg signal, we have established the presence and characteristic of collinear antiferromagnetism in RuO_{2} with T_{N}300 K. In addition to revealing a spin-ordered ground state in the simplest ruthenium oxide compound, the persistence of magnetic order even in nanometer-thick films lays the ground for potential applications of RuO_{2} in antiferromagnetic spintronics.

Due to the impact of global warming and increasing cost of fossil fuels day by day, development of alternative sources of energy has become important so that the world’s future energy needs can be mitigated. The focus has been given to develop economically viable and environment friendly technologies. Among all the forms of alternate energy sources, biohydrogen (BioH2) is of significant interest due to its carbon neutral combustion. Use of second-generation (lignocelluloses) and third-generation feedstocks (algae) to produce BioH2 can be a promising and efficient method, which fulfills the future demand of energy. Recently, BioH2 production using extremophiles has gained high attention due to fast production rate without any preprocessing or mild processing of plant biomass. Extremophiles are reported to produce BioH2 and other value-added products even from untreated lignocellulosic biomass. This chapter presents a review and in-depth analyses of extremophilic BioH2 production from lignocellulosic biomass. The chapter also provides the knowledge on how to develop a more efficient and economical integrated process for enhanced conversion of lignocellulosic feedstocks to BioH2.

The near-surface layers in the Arabian Sea progressively warm up from February to early May resulting in the formation of pool of warm waters popularly known as the Arabian Sea Warm Pool (ASWP). The availability of high quality TMI sea surface temperature (SST) data for the years 1998–2010 is exploited to describe the evolution of the ASWP on seasonal and interannual time scales and to explain the associated mechanisms. The multi-year (1998–2010) averaged TMI SSTs during April–May show peak values of the ASWP in excess of 30 °C with its core >30.5 °C extending offshore as a well-marked southwestward tongue stretching from the southwest coast of India. The ASWP shows both seasonal and interannual variability in the evolution of spatio-temporal characteristics such as amplitude, phase and spatial extent. Among these 13 years, the ASWP was most (least) pronounced during 1998, 2003 and 2010 (1999, 2000, 2001 and 2008). The mechanisms that govern the observed interannual variability of the ASWP are examined addressing the most relevant issues such as—(1) dynamic pre-conditioning: background pycnocline topography influenced by the westward propagating Rossby waves during October–May, (2) thermal pre-conditioning: background SST/heat content signal during October–January influenced by the strength of the preceding year’s summer monsoon and the post-monsoon cyclones during October–December, (3) haline pre-conditioning: near-surface vertical salinity stratification during November–February influenced by the advection of low saline waters from the Bay of Bengal, (4) influence of surface net heat flux forcing during February–May, and (5) influence of El Nino/La Nina.

Feelings and experiences of the author over Classical Taxonomy in India during the last 4 decades is discussed. Brief history and outline of development of the subject is provided. The systematic exploratory phase of taxonomy is said to have started around the middle of 16th century and with two major events, the subject reached its peak. The first one being the development of the concept of Herbarium and second one being the introduction of the Binomial System of Nomenclature by Linnaeus in 1753. Both the events laid the firm foundation for Classical Taxonomy. But during the last few decades with the development of Bio-systematic phase, although revolutionary changes in concepts of taxonomy could be noticed, the Classical Taxonomy got completely side tracked. Discussing the current status of Taxonomy in the country, the author emphasizes the dwindling nature of the subject. Among many other causes, development of more fashionable and experimental areas of modern biology, faulty methods of teaching by untrained taxonomists in most Universities, lack of sufficient taxonomic literature and herbaria, synthetic nature of discipline of taxonomy, lack of sufficient number of practicing taxonomists and field botanists to carry out the survey and documentation of the vast diversity of the flora of India, most taxonomic journals with least or no impact factor, low citation index of Classical Taxonomists, development of computer databases and computer identification devices by non-taxonomists, molecular biologists side tracking the Classical Taxonomists in areas of biodiversity assessments, avoidance of taxonomists by modern biologists in programmes of Bioprospection, apathy towards the subject by fund giving bodies and lastly, least recognitions of Classical Taxonomists by scientific bodies are cited as prominent reasons for the decline of the subject. Although Botanical Survey of India has done a commendable job in accomplishing the tasks of Taxonomists, some how the organization has failed in generating and enthusing the required number of younger taxonomists and group specialists in the country. Worse is the case with many Universities who have, to some extent killed the subject. All these factors have collectively brought about a serious decline in the subject resulting in the acute shortage of younger generation of field botanists and taxonomists who are to shoulder the big responsibilities of inventorizing the rich biodiversity in the tropics. However, the situation is not that hopeless. The achievements of Classical Taxonomists during the last 4 decades in inventorization and documentation of the flora of the country is commendable. Today the dimensions and scope of the subject have widened beyond imagination. Floristic taxonomists are sought after by many for taking part in applied aspects such as bio-prospection, new drug discoveries, search for alternate economic plant resources, conservation of biological resources and monitoring of fragile ecosystems. The author strongly feels that taxonomy with the additional objectives and broadened scope will certainly regain its past glory and become one of the challenging disciplines of biology in the 21st century.

During winter, along the east coast of India, the near-surface flow is characterized by the southward-flowing East India Coastal Current EICC which bends around Sri Lanka and enters into the south-eastern Arabian Sea AS. This current carries cooler, low-salinity waters from the head Bay of Bengal BoB into the south-eastern AS. But due to a lack of any direct in situ measurements, it is not clear whether any part of this current that flows through the Indo-Sri Lanka Channel ISLC is significant. An attempt is made in this study to look for any observational evidence for the southward flow of cooler, low salinity waters through the ISLC during winter. In the absence of direct in situ measurements on the observed currents in the non-navigable shallow ISLC, the observed high resolution, advanced very high resolution radiometer AVHRR sea surface temperature SST, and sea-viewing wide field-of-view sensor SeaWiFS chlorophyll-a and historic sea surface salinity SSS data are utilized as tracers to track any southward water flow through the Pamban Pass and Adam's Bridge in the ISLC. The analysis suggests that both the non-navigable shallow Pamban Pass and the Adam's Bridge in the ISLC act as barriers and limit the southward flow of cooler, low salinity waters into the Gulf of Mannar in the south during winter.

Sertaconazole is a new antifungal agent. To compare the efficacy and tolerability of sertaconazole and miconazole cream in cutaneous dermatophytosis, this prospective, randomized, multicentric comparative, phase 4 study was undertaken in 260 patients with cutaneous dermatophytosis after approvals from Institutional Ethics Committees. Patients were assigned to sertaconazole cream (2%) or miconazole cream (2%) topically twice daily for 2 weeks after obtaining informed consent. Efficacy variables included changes in mean scores of erythema, pruritus, desquamation, erythema/itching, burning/weeping, scaling/pustule and overall global assessment. Safety and tolerability were also assessed. A total of 122 patients in the sertaconazole group and 128 in the miconazole group completed the study with 10 drop-outs. There was a significant decrease (P < 0.05) in mean symptom scores and total scores from the first week onwards, sustained till 2 weeks and statistically significant (P < 0.05) in favour of sertaconazole. Moreover, 62.3% patients had complete clinical cure in the sertaconazole group (P < 0.05) compared with 44.6% in miconazole users. Both drugs were well tolerated and five patients in the sertaconazole group and nine in the miconazole group reported mild to moderate adverse events. Therapy with sertaconazole cream (2%) provided a better efficacy and tolerability compared with the miconazole cream (2%) and could thus be a therapeutic option in cutaneous dermatophytosis.

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.

Biofuels have been considered as an alternative energy source to cope up the future energy demand. There are various biomass-based energy sources including biogas, bioethanol, biobutanol, etc. Biogas is one of the biofuels which can be produced from the lignocellulosic biomass. Cellulose, hemicellulose, lignin, and several inorganic materials constitute lignocelluloses. Lignocelluloses are often the sole component of different agricultural waste such as paddy straw. Paddy straw is one of the lignocellulosic biomass that can be used as feedstock for biogas production because of its great profusion, sustainable supply, and low price. This type of biomass is not fully biodegraded in anaerobic digestion process at industrial scale due to their intricate physical and chemical structure that consequently leads to lower energy resurgence in terms of biogas yield. The biodegradability of these lignocelluloses waste can be increased by a pretreatment. Therefore, breakdown of complex materials to simpler ones or to make cellulose accessible to hydrolytic enzymes is the key step for better digestion to biogas. The aim of this paper is to review promising pretreatment technologies which have greatly improved the production of biogas. Effective parameters in paddy straw pretreatment involve increased fortification by lignin and hemicelluloses. Various pretreatment methods such as mechanical, thermal, chemical, biological, and their advantages and disadvantages as well as effects on the improvement of biogas production are discussed.

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.

Lanthanum hexa-aluminate (LHA) is considered a promising material for thermal barrier coatings for gas turbine applications as well as oxidation resistant coatings for fibres in oxide based ceramic composites. Combustion synthesis has attractive advantages such as simple experimental setup, low cost, short reaction time, energy savings due to exothermic reaction, better control of stoichiometry and fine powder size. The present study involves combustion synthesis of LHA using lanthanum and aluminium nitrates as oxidising precursors, and urea as fuel. The precursor salts were dissolved in a minimum amount of deionised water and the solution was heated in a mantle heater to temperatures of around 300–350°C, at which combustion takes place with rapid evolution of gas. The LHA powder was also prepared by a precipitation route for comparative study. The as synthesised powders were calcined at up to 1450°C and subjected to X-ray diffraction for phase evolution studies. Product powders were then characte...

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.

A subset of the global ocean temperature climatology is used to characterize the observed seasonal variability in the near-surface thermal structure of the tropical Indian Ocean. In the near-surface isothermal layer the seasonal variability is least in the warm pool region and increases poleward. Over much of the tropical Indian Ocean, local surface heat fluxes overwhelm horizontal advection in the seasonal evolution of the mixed layer temperature. Entrainment cooling is weaker by an order of magnitude than the other two processes. Several dynamical processes produce the most prominent signals in the thermocline in different geographic regions, such as coastal upwelling/downwelling with associated reversals in the flow off Arabia, off southwest India, and off the east coast of India, Ekman-driven thermocline deepening in the central Arabian Sea, convergence of waters caused by Wyrtki Equatorial Jets in the eastern equatorial Indian Ocean, Ekman divergence of a dome of cold waters just south of the equator in the west, propagating Kelvin waves in the coastal regions of the Bay of Bengal, and propagating Rossby waves from off southwest India to Somalia and in the Indo-Pacific throughflow region. For the spatiotemporal resolutions considered in this study the penetration of the seasonal cycle of temperature appears to be limited to 150 m depth or so. Numerical model solutions have revealed the causative mechanisms for some of the prominent signals seen in the observations, in particular, those driven by long-period propagating waves in regions of large stratification, whose structure was not revealed by earlier climatologies to date, as revealed by this new climatology.

The paper enumerates four varieties of Berberis lycium ROYLE. Morphological, distributional, leaf epidermal and pollen morphological data have been appended to show that the varieties – lycium, subfascicularis AHRENDT, simlensis AHRENDT and subvirescens AHRENDT are distinct. In der Arbeit werden vier Varietaten von Berberis lycium ROYLE aufgezahlt. Daten zur Morphologie, Verbreitung, Blattepidermis und Pollenmorphologie werden ausgewertet. Dabei zeigt es sich, das die Varietaten lycium, subfascicularis AHRENDT, simlensis AHRENDT und subvirescens AHRENDT sich voneinander unterscheiden.

Aconitum (Ranunculaceae) in North-West Himalaya is represented by ten species and two varieties. Although most species of Aconitum exhibit remarkable morphological variations, no infraspecifc taxa have been recognized (except under A. heterophyllum) as these variation are observed to be continuous. A. heterophyllum and A. violaceum are shown to be morphologically highly diverse. Genetic diversity in this group is least studied. The taxonomic treatment of the genus includes a key to all species, correct nomenclature, distribution and usefull taxonomic notes, where possible. In the present study A. ovatum and A. cordatum have been shifted back under A. heterophyllum. A. kashmiricum is also treated here as a morphological variant of A. heterophyllum. A. balfourii var. rhombilobum, A. falconri var. latilobum, A. heterophyllum subsp. parciflorum, A. laeve var. curvipilosum, A. violaceum var. robustum and A. violaceum var. weilerii have been reduced as synonyms under their typical varieties. A. falconeri has been reported for the first time from Kumaon Himalaya. A. heterophyllum var. roylei var. nova is described here as a new variety. Lectotypification has also been done for a few species. Discussing the current status of the species, it is said that owing to the medicinal virtues, most species of the genus have become critically endangered in their type localities. Both – in situ and ex situ – efforts are recommended to conserve the genetic diversity in these species. Die Gattung Aconitum ist im Nordwest-Himalaya mit zehn Arten und zwei Varietaten vertreten. Obwohl die meisten Aconitum-Arten eine beachtliche morphologische Variabilitat zeigen, wurden keine infraspezifischen Taxa ausgeschieden (ausgenommen unter A. heterophyllum, weil die Varietaten als konstant angesehen werden). A. heterophyllum und A. violaceum erwiesen sich als morphologisch sehr unterschiedlich. Die genetische Diversitat wurde letztlich in dieser Gruppe untersucht. Die taxonomische Behandlung der Gattung schliest einen Schlussel aller Arten, korrekte Nomenklatur, Verbreitungsangaben und – wenn moglich – taxonomische Bemerkungen ein. In der vorliegenden Untersuchung wurden A. ovatum und A. cordatum wieder mit A. heterophyllum vereint. A. kashmiricum wird hier als morphologische Variante von A. heterophyllum behandelt. A. balfourii var. rhombilobum, A. falconeri var. latilobum, A. heterophyllum subsp. parciflorum, A. laeve var. curvipilosum sowie A. violaceum var. robustum und A. violaceum var. weileri wurden als Synonyme ihren typischen Varietaten zugeordnet. A. falconeri wird hier zum ersten mal vom Kumaon Himalaya erwahnt. A. heterophyllum var. roylei var. nova wird als neue Varietat beschrieben. Fur einige Arten wird die Lectotypification durchgefuhrt. Bei Erorterung des derzeitigen Status der Arten unter Berucksichtigung ihrer medizinischen Bedeutung ist festzustellen, das die meisten Arten der Gattung an ihren Typus-Standorten gefahrdet sind. Beide Moglichkeiten – in situ und ex situ – zur Erhaltung der genetischen Diversitat dieser Arten empfohlen werden.

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

A subset of world ocean monthly mean temperature climatology generated by Levitus and Boyer (1994), is utilised to describe the observed seasonal variability of the characteristics of the near-surface isothermal layer and thermocline for the entire tropical Indian Ocean (TIO). The most salient features of the observed annual cycle are described in terms of amplitude and phase of the annual and semi-annual frequencies employing Fourier analysis technique. On the annual mode, the near-surface isothermal layer depth (ILD), exhibits larger variability away from the equator with peak values in the northernmost Arabian Sea, the northernmost Bay of Bengal and the southern TIO, while on the semi-annual mode, it shows larger variability in the central Arabian Sea. The variability of the near-surface isothermal layer temperature (ILT), on the annual mode, is very weak in the warmpool region, and increases with latitude, while on the semi-annual mode, it shows larger variability in the northwestern Arabian Sea. The variability of 20°C isotherm topography (D20), on the annual mode, is weakest in the equatorial region and largest in the coastal regions of the Arabian Sea and the Bay of Bengal and in the southern T10, while on the semi-annual mode, it is prominent in the eastern and western equatorial regions. The thermocline gradient (TG) is very sharp below the warmpool region and diffuses meridionally. On the annual mode, it shows larger variability in the southern TIO, off Somalia and northernmost Arabian Sea, while on the semiannual mode, it shows larger variability in the southwestern Arabian Sea and eastern equatorial Indian Ocean. The relationship between near-surface isothermal layer and thermocline characteristics over an annual cycle are explored through correlation analysis. The correlation between ILD and ILT is strong over much of the basin with the exception of the equatorial and coastal upwelling/downwelling zones where internal ocean dynamics are important. In the southern TIO, entrainment of colder waters appears to be important in maintaining the annual cycle of ILT as strong correlation is noticed between ILT and TG. In the Indo-Pacific throughflow region and another region west of it, the annual Rossby waves appear to control D20, as correlations between D20 and other fields are strong in these regions. A similar strong correlation between D20 and ILD is also noticed in the southeastern Arabian Sea where mode-2 Rossby waves identified in numerical model solutions.

A systematic study of separating the actinides from each other in 1 M hydrochloric acid media has been carried out using selective oxidation/reduction processes followed by coprecipitation with neodymium fluoride. We have optimized two such procedures, one with bromate and another with permanganate, for the sequential separation of Am, Pu, Np, and U isotopes. The first procedure involves oxidation of Pu, Np, and U to +6 state in 1 M HCl media at 85° C with 30% NaBrO3 and separation from trivalent Am by collecting the latter on the first NdF3 coprecipitated source. Plutonium is then reduced and converted to +4 oxidation state with 40% NaNO2 at 85°C, while Np and U are kept oxidized with additional bromate in 50–70°C hot solution, thus separating Pu by collection on a second NdF3 source. At this stage, Np present in the filtrate is reduced with hydroxylamine hydrochloride and separated from U by collecting on a third source. Subsequently, U is reduced with 30% TiCl3 and co-precipitated on a final source. The second procedure, which employs KMnO4 in 1 M HCl media at 60–85°C for oxidizing Pu, Np, and U, and separating from Am, produced MnO2 which is collected along with Am on the coprecipitated NdF3. This MnO2 is dissolved on the filter itself with 1 mL of acidified 1.5% H2O2 without any degradation of the α-spectra. After evaporating the filtrate to destroy H2O2, Pu, Np, and U are separated by following steps similar to those in the bromate procedure. The recoveries of the actinides with both procedures are >99%. The decontamination factors are between 103 and 104. The precision and accuracy of measurements, as expressed by the relative standard deviation of replicate analyses, are within 5%. Absolute detection limits for a one-day count on a 600 mm2 detector at 32% counting efficiency and 450 mm2 detector at 27% counting efficiency are about 2.7×10−4 and 3.2×10−4 Bq, respectively. These procedures have been applied to the analysis of actinides in environmental samples.

The equilibrium extraction behavior of Sm(III), Eu(III) and Dy(III) from aqueous NaClO4 solutions in the pH range of 4–9 at 0.1 M ionic strength into organic solutions of 1-nitroso-2-naphthol (HA) and 1,10-phenanthroline (Phen) has been studied. The equilibrium concentrations of Eu were assayed through the 344 keV photopeak of the152Eu radiotracer used. The concentrations of Sm and Dy were measured by irradiating one mL portions of the organic extract and analyzing the 104 and 108 keV photopeaks of the short-lived neutron activation products,155Sm and165mDy, respectively. Quantitative extraction of Eu with 5×10−2 M HA alone was obtained in the pH range of 6.7–7.8 with n-butanol, 7.4–8.5 with chloroform, 8.0–8.7 with ethyl acetate, 7.7–8.5 with isoamyl alcohol and 6.1–8.0 with methyl isobutyl ketone (MIBK). But, Eu was extracted only to a maximum of 78% and 83% in the pH range of 8.3–8.9 and 7.4–8.1 with carbon tetrachloride and xylene, respectively. The extraction of Sm and Dy were found quantitative in the pH range of 6.3–7.0 and 6.6–7.1, respectively, with 5×10−2 M HA alone in MIBK solutions. The synergistic extraction of Eu was quantitative in the pH range of 6.6–9.8 with chloroform, 7.8–8.9 with ethyl acetate, 7.7–8.5 with isoamyl alcohol and 6.0–9.6 with MIBK when 1×10−2 M each of HA and Phen were employed. Sm and Dy were quantitatively extracted into MIBK solutions containing 5×10−2 M each of HA and Phen in the pH range 6.0–7.5 and 6.1–7.5, respectively. The distribution ratios of these lanthanides (Ln) were determined as a function of pH, and HA and Phen concentrations. The analysis of the data suggests that these Ln are extracted as LnA3 chelates when HA alone is used. In the presence of HA and Phen, both LnA3(Phen) and LnA3(Phen)2 adducts are formed only in the MIBK system while LnA3(Phen) complexes are the predominant ones in all other solvent systems studied. The extraction constants and the adduct formation constants of these complexes have been calculated.

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.

This chapter describes floristic changes, particularly in the herbaceous flora, that have occurred during recent years due to the introduction and spread of alien invasive weeds in Meghalaya and other states in north-east India. Factors favouring biological invasions are briefly covered. Some of the worst invasive weeds that have affected human health and the economic status of the tribal populations of the region are presented: Mikania micrantha, Lantana camara, Chromolaena odorata, Ageratina adenophora, Eichhornia crassipes, Galinsoga quadriradiata and Parthenium hysterophorus.

This chapter describes the utilization of invasive weeds in the Western Ghats region of India as medicinal plants, ornamental plants, edible plants, fodder plants, hyperaccumulators for bioremediation, biofertilizers and timber source, among other uses.

This chapter describes the characteristics of invasive alien species that are associated with their invasive nature, factors influencing the introduction of invasive species, and ecological disturbance resulting from the introduction of invasive species. The taxonomy, morphology and geographical distribution of 42 invasive species in the Western Ghats region in India (i.e. classified under Amaranthaceae, Araceae, Butomaceae, Calceolariaceae, Caesalpiniaceae, Convolvulaceae, Euphorbiaceae, Fabaceae, Lamiaceae, Melastomataceae, Mimosaceae, Papaveraceae, Pontederiaceae, Salviniaceae, Typhaceae and Verbenaceae) are briefly covered.

The extraction behavior of Sm(III), Eu(III) and Dy(III) with 1-nitroso-2-naphthol (HA) and trioctylphosphine oxide (TOPO) in methyl isobutyl ketone (MIBK) from aqueous NaClO4 solutions in the pH range 4–9 at 0.1M ionic strength has been studied. The equilibrium concentrations of Sm and Dy were measured using their short-lived neutron activation products,155Sm and165mDy, respectively. In the case of Eu, the concentrations were assayed through the152,154Eu radiotracer. The distribution ratios of these elements were determined as a function of pH, 1-nitroso-2-naphthol and TOPO concentrations. The extractions of Sm, Eu and Dy were found to be quantitative with MIBK solutions in the pH range 5.9–7.5, 5.6–7.5 and 5.8–7.5, respectively. Quantitative extraction of Eu was also obtained between pH 5.8 and 8.8 with chloroform solutions. The results show that these lanthanides (Ln) are extracted as LnA3 chelates with 1-nitroso-2-naphthol alone, and in the presence of TOPO as LnA3(TOPO) and LnA3(TOPO)2 adducts. The extraction constants and the adduct formation constants of these complexes have been calculated.