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The densely populated Bay of Bengal (BoB) rim witnesses the deadliest tropical cyclones (TCs) globally, before and after the summer monsoon. Previous studies indicated that enhanced salinity and reduced thermal stratification reduce cooling under BoB TCs after the monsoon, suggesting that air‐sea coupling may favor stronger TCs during that season. Using observations and simulations from a one fourth degree regional ocean‐atmosphere model, we show that BoB TCs are stronger before the monsoon due to a more favorable large‐scale background state (less vertical wind shear and higher sea surface temperature). Air‐sea coupling however alleviates this background state influence, by reducing the number of premonsoon intense TCs, because of larger cooling and reduced upward enthalpy fluxes below TCs during that season. As the impact of air‐sea interactions on BoB TCs is largest for intense TCs, it should be further investigated for Category 3 and above TCs, which are not reproduced at one fourth degree resolution. Tropical cyclones that develop in the Bay of Bengal are amongst the most lethal globally, owing to the dense and vulnerable coastal population living along its rim. These cyclones mostly occur in April–May and October–December, that is, before and after the Indian summer monsoon. In this study, we show that there are more intense cyclones before than after the monsoon, because of more favorable large‐scale background conditions. We however also show that more intense interactions between the cyclone and the ocean tend to reduce risks for intense cyclones before the monsoon, hence opposing the effect of background conditions. Since air‐sea coupling clearly contributes to the Bay of Bengal cyclone intensity, in particular before the monsoon, it should be accounted for in operational forecasts. Bay of Bengal tropical cyclones are stronger before than after the monsoon, due to more favorable large‐scale background conditionsAir‐sea coupling alleviates the effect of large‐scale background conditions, by inhibiting premonsoon tropical cyclonesThe air‐sea coupling negative feedback on tropical cyclones is weak after the monsoon, due to a fresher, less thermally stratified BoB

The response of the Indian winter monsoon to climate change has received considerably less attention than that of the summer monsoon. We show here that all Coupled Model Intercomparison Project Phase 5 (CMIP5) models display a consistent reduction (of 6.5% for Representative Concentration Pathways 8.5 and 3.5% for 4.5, on an average) of the winter monsoon winds over the Arabian Sea at the end of 21st century. This projected reduction weakens but remains robust when corrected for overestimated winter Arabian Sea winds in CMIP5. This weakening is driven by a reduction in the interhemispheric sea level pressure gradient resulting from enhanced warming of the dry Arabian Peninsula relative to the southern Indian Ocean. The wind weakening reduces winter oceanic heat losses to the atmosphere and deepening of convective mixed layer in the northern Arabian Sea and hence can potentially inhibit the seasonal chlorophyll bloom that contributes substantially to the Arabian Sea annual productivity. The Indian summer monsoon response to climate change has been previously the focus of many studies. The Indian winter monsoon‐projected response to climate change is, however, largely unexplored. This is the first study to report a robust weakening of the Indian winter monsoon winds over the Arabian Sea in two Coupled Model Intercomparison Project Phase 5 scenarios (an unmitigated and a mitigated one). The wind weakening leads to reduced winter oceanic convective overturning in the northern Arabian Sea. This winter convection is the key mechanism for a productivity (winter) bloom that strongly contributes to the Arabian Sea annual productivity. The projected winter monsoon weakening may thus reduce the Arabian Sea productivity. We also show a rainfall increase that could affect water supply in tropical Indian Ocean islands and Eastern Africa. This study reports a robust reduction of the northeast monsoon winds over the Arabian Sea under two climate change scenariosThe wind weakening is driven by a reduction of the Interhemispheric sea level pressure gradientWeakening of winds leads to a reduced winter mixed layer deepening in the northern Arabian Sea and hence less oceanic productivity

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. Surface layer temperature inversion (SLTI) in the Bay of Bengal occurs during winterSLTI has significant interannual and intraseasonal variabilityNet surface heat loss is the most dominant process controlling the formation and maintenance of SLTI

The strong seasonal cycle of sea level along the west coast of India (WCI) has important consequences for ecosystem and fisheries, and the Lakshadweep high/low in the southeast Arabian Sea is important for fisheries and the Indian summer monsoon. Previous studies suggested that WCI sea level variability is primarily driven by remote wind forcing from the Bay of Bengal and equatorial Indian Ocean through coastal Kelvin wave propagation. Using a linear ocean model, we demonstrate that wind forcing in a relatively small region around the southern tip of India and east of Sri Lanka contribute to ~60% of this variability. Wind variations from the rest of the Bay and the equator only account respectively for ~20% and ~10%. Sea level signals forced by the “southern tip” winds extend westward into the eastern Arabian Sea through Rossby wave propagation, with more than 50% contribution in the Lakshadweep high/low region. Winds near Sri Lanka drive 60% of Indian west coast seasonal sea levelBay of Bengal wind forcing contributes to only 20%Winds near Sri Lanka are also essential for driving Lakshadweep high/low

To assess the feasibility and to audit the practice of determining chorionicity in twin pregnancies in South India. Sonographic findings from first trimester scans of twin pregnancies were retrospectively analysed to evaluate the feasibility of determining chorionicity in the first visit to the unit. In addition, an audit was carried out on all twin pregnancies referred to the authors in the second trimester to ascertain whether chorionicity had been established prior to referral. It was feasible to determine chorionicity at the first visit in 100 % of the 611 twin pregnancies that were seen at 11–14 weeks in the unit. However, the audit revealed that only 40 % of the referred population had a diagnosis of chorionicity prior to referral. Whilst it is feasible to determine chorionicity in all twin pregnancies in the first trimester, the practice is not widespread in the referring community in South India and this needs to be addressed.

Introduction:Mild stress-induced hormesis is becoming increasingly attractive as an ageing interventional strategy and is leading to the discovery of hormesis-inducing compounds called hormetins. Almost 50 years of modern biogerontolgical research has established a clear framework regarding the biological basis of ageing and longevity, and it is now generally accepted that ageing occurs in spite of the presence of complex pathways of maintenance, repair and defense, and there is no ‘enemy within.’ This viewpoint makes modulation of ageing different from the treatment of one or more age-related diseases. A promising strategy to slow down ageing and prevent or delay the onset of age-related diseases is that of mild stress-induced hormesis by using hormetins.Areas covered:The article presents the rationale and a strategy for discovering novel hormetins as potential drugs for ageing intervention by elucidating multiple stress responses of normal human cells. Furthermore, it discusses the first steps in identifying prospective hormetin drugs and provides a recent example of successful product development, based on the ideas of hormesis and by following the strategy described here.Expert opinion:As a biomedical issue, the biological process of ageing underlies several major diseases, and although the optimal treatment of every disease, irrespective of age, is a social and moral necessity, preventing the onset of age-related diseases by intervening in the basic process of ageing is the best approach for achieving healthy ageing and for extending the healthspan.

Overexpression of platelet-derived growth factor receptor alpha (PDGFR-A) has been documented in association with primary tumors and metastasis in medulloblastoma. Tumors from our genetically engineered sonic hedgehog-driven medulloblastoma mouse model overexpress PDGFR-A in primary tumors and thus this mouse model is a good platform with which to study the role of PDGFR-A in this central nervous system malignancy. We hypothesized that inhibition of PDGFR-A in medulloblastoma can slow or inhibit tumor progression in living individuals. To test our hypothesis, we targeted PDGFR-A mediated tumor growth in vitro and in vivo using the tyrosine kinase inhibitor, tandutinib (MLN-518), which strongly inhibits PDGFR-A. Although PDGFR-A inhibition by this agent resulted in reduced mouse tumor cell growth and increased apoptosis in vitro, and reduced tumor cell proliferation in vivo, tandutinib did reduce tumor volume at the doses tested (360 mgkg) in vivo. Thus, tandutinib may be an agent of interest for sonic hedgehog-driven medulloblastoma if a synergistic drug combination can be identified.

In 2008, the World Economic Forum (WEF) created the Global Agenda Councils – an amalgamation of scientists, public policy makers, academics, physicians and business leaders with the task of devising transformational innovation in global governance for the purpose of advancing knowledge and collaboratively developing solutions for the most crucial issues facing humanity. Because of its overarching effect on many aspects of society, a Council was created to address global issues associated with an ageing society. The Councils have the task of challenging prevailing assumptions, monitoring trends, proposing solutions, devising strategies, making public policy proposals and evaluating the effectiveness of actions using measurable benchmarks. This report is the first product of the WEF’s Council on the Ageing Society – our goal is to lay down the initial principles that will guide our actions in the coming years.

Pituitary adenomas are classified into functioning and nonfunctioning (silent) tumors on the basis of hormone secretion. However, the mechanism of tumorigenesis and the cell of origin for pituitary adenoma subtypes remain to be elucidated. Employing a tamoxifen-inducible mouse model, we demonstrate that a novel postnatal Pax7+progenitor cell population in the pituitary gland gives rise to silent corticotroph macro-adenomas when the retinoblastoma tumor suppressor is conditionally deleted. While Pax transcriptional factors are critical for embryonic patterning as well as postnatal stem cell renewal for many organs, we have discovered that Pax7 marks a restricted cell population in the postnatal pituitary intermediate lobe. This Pax7+early progenitor cell population is overlapping but ontologically downstream of the Nestin+pituitary stem cell population, yet upstream of another newly discovered Myf6+late progenitor cell population. Interestingly, the Pax7+progenitor cell population is evolutionarily conserved in primates and humans, and Pax7 expression is maintained not only in murine tumors but also in human functioning and silent corticotropinomas. Taken together, our results strongly suggest that human silent corticotroph adenomas may in fact arise from a Pax7 lineage of the intermediate lobe, a region of the human pituitary bearing closer scientific interest as a reservoir of pituitary progenitor cells.

Abstract: This paper describes the variability in the diurnal range of SST in the north Indian Ocean using in situ measurements and tests the suitability of simple regression models in estimating the diurnal range. SST measurements obtained from 1556 drifting and 25 moored buoys were used to determine the diurnal range of SSTs. The magnitude of diurnal range of SST was highest in spring and lowest in summer monsoon. Except in spring, nearly 75–80% of the observations reported diurnal range below 0.5°C. The distributions of the magnitudes of diurnal warming across the three basins of north Indian Ocean (Arabian Sea, Bay of Bengal and Equatorial Indian Ocean) were similar except for the differences between the Arabian Sea and the other two basins during November–February (winter monsoon) and May. The magnitude of diurnal warming that depended on the location of temperature sensor below the water level varied with seasons. In spring, the magnitude of diurnal warming diminished drastically with the increase in the depth of temperature sensor. The diurnal range estimated using the drifting buoy data was higher than the diurnal range estimated using moored buoys fitted with temperature sensors at greater depths. A simple regression model based on the peak solar radiation and average wind speed was good enough to estimate the diurnal range of SST at ∼1.0 m in the north Indian Ocean during most of the seasons except under low wind-high solar radiation conditions that occur mostly during spring. The additional information on the rate of precipitation is found to be redundant for the estimation of the magnitude of diurnal warming at those depths.

Abstract: Ocean modellers use bathymetric datasets like ETOPO5 and ETOPO2 to represent the ocean bottom topography. The former dataset is based on digitization of depth contours greater than 200 m, and the latter is based on satellite altimetry. Hence, they are not always reliable in shallow regions. An improved shelf bathymetry for the Indian Ocean region (20°E to 112°E and 38°S to 32°N) is derived by digitizing the depth contours and sounding depths less than 200 m from the hydrographic charts published by the National Hydrographic Office, India. The digitized data are then gridded and used to modify the existing ETOPO5 and ETOPO2 datasets for depths less than 200 m. In combining the digitized data with the original ETOPO dataset, we apply an appropriate blending technique near the 200 m contour to ensure smooth merging of the datasets. Using the modified ETOPO5, we demonstrate that the original ETOPO5 is indeed inaccurate in depths of less than 200 m and has features that are not actually present on the ocean bottom. Though the present version of ETOPO2 (ETOPO2v2) is a better bathymetry compared to its earlier versions, there are still differences between the ETOPO2v2 and the modified ETOPO2. We assess the improvements of these bathymetric grids with the performance of existing models of tidal circulation and tsunami propagation.

The Great Tsunami of 26 December 2004 is described using data from seven tide gauges in India and others from surrounding areas in the Indian Ocean. The tsunami struck the Indian east coast around 0330 UTC. The amplitude was 2 m above the tide at Chennai, Paradip, and Colombo. The east coast of India (and of Sri Lanka) was hit shortly after high tide; Tuticorin and Colombo, however, were hit shortly after low tide. The tsunami wave propagated northward along the Indian west coast. All these gauges are to the west of the earthquake zone and the detided sea levels show first a rise in sea level with the arrival of the tsunami, and then a sharp decrease. Spectral and wavelet analysis of the detided series show that the maximum amplitude was at a period of 35–45 minutes, with another maximum around 20 minutes. Along the Indian east coast, however, there is another broad peak between 1–2 hours within the first few hours after the first tsunami wave.

The phenomenon of hormesis is represented by mild stress-induced stimulation of maintenance and repair pathways, resulting in beneficial effects for cells and organisms. We have reported that repeated mild heat stress (RMHS) has anti-aging hormetic effects on growth and various cellular and biochemical characteristics of human skin fibroblasts undergoing aging in vitro. These effects of RMHS include the maintenance of the stress protein profile, reduction in the accumulation of oxidatively and glycoxidatively damaged proteins, stimulation of the activities of the proteasome and its 11S activator, improvement in cellular resistance to ethanol, hydrogen peroxide, and ultraviolet rays, and increased antioxidative activity of the cells. We have also reported that RMHS prolongs the lifespan of Drosophila. Others have reported anti-aging and life prolonging effects of a wide variety of so-called stressors, such as pro-oxidants, aldehydes, calorie restriction, irradiation, heat shock, and hypergravity. Although molecular mechanisms of hormesis are yet to be elucidated, there are indications that relatively small hormetic effects become biologically amplified, resulting in significant improvement of cellular and organic functions and survival. Hormesis, therefore, can be an effective approach for modulating aging, for preventing or delaying the onset of age-related diseases, and for improving the quality of life in old age.

Decreased bone formation is an important pathophysiological mechanism responsible for bone loss associated with aging and osteoporosis. Osteoblasts (OBs), originate from mesenchymal stem cells (MSCs) that are present in the bone marrow and form colonies (termed colony‐forming units‐fibroblastic [CFU‐Fs]) when cultured in vitro. To examine the effect of aging and osteoporosis on the MSC population, we quantified the number of MSCs and their proliferative capacity in vitro. Fifty‐one individuals were studied: 38 normal volunteers (23 young individuals [age, 22‐44 years] and 15 old individuals [age, 66‐74 years]) and 13 patients with osteoporosis (age, 58‐83 years). Bone marrow was aspirated from iliac crest; mononuclear cells were enriched in MSCs by magnetic activated cell sorting (MACS) using STRO‐1 antibody. Total CFU‐F number, size distribution, cell density per CFU‐F, number of alkaline phosphatase positive (ALP+) CFU‐Fs, and the total ALP+cells were determined. In addition, matrix mineralization as estimated by alizarin red S (AR‐S) staining was quantified. No significant difference in colony‐forming efficiency between young individuals (mean ± SEM; 87 ± 12 CFU‐Fs/culture), old individuals (99 ± 19 CFU‐Fs/culture), and patients with osteoporosis (129 ± 13 CFU‐Fs/culture; p= 0.20) was found. Average CFU‐F size and cell density per colony were similar in the three groups. Neither the percentage of ALP+CFU‐Fs (66 ± 6%, 65 ± 7%, and 72 ± 4% for young individuals, old individuals, and patients with osteoporosis, respectively) nor the percentage of ALP+cells per culture (34 ± 5%, 40 ± 6%, and 41 ± 4%) differed between groups. Finally, mineralized matrix formation was similar in young individuals, old individuals, and patients with osteoporosis. Our study shows that the number and proliferative capacity of osteoprogenitor cells are maintained during aging and in patients with osteoporosis and that other mechanisms must be responsible for the defective osteoblast (OB) functions observed in these conditions.

Decreased bone formation is an important pathophysiological mechanism responsible for bone loss associated with aging and osteoporosis. Osteoblasts (OBs), originate from mesenchymal stem cells (MSCs) that are present in the bone marrow and form colonies (termed colony‐forming units‐fibroblastic [CFU‐Fs]) when cultured in vitro. To examine the effect of aging and osteoporosis on the MSC population, we quantified the number of MSCs and their proliferative capacity in vitro. Fifty‐one individuals were studied: 38 normal volunteers (23 young individuals [age, 22‐44 years] and 15 old individuals [age, 66‐74 years]) and 13 patients with osteoporosis (age, 58‐83 years). Bone marrow was aspirated from iliac crest; mononuclear cells were enriched in MSCs by magnetic activated cell sorting (MACS) using STRO‐1 antibody. Total CFU‐F number, size distribution, cell density per CFU‐F, number of alkaline phosphatase positive (ALP+) CFU‐Fs, and the total ALP+cells were determined. In addition, matrix mineralization as estimated by alizarin red S (AR‐S) staining was quantified. No significant difference in colony‐forming efficiency between young individuals (mean ± SEM; 87 ± 12 CFU‐Fs/culture), old individuals (99 ± 19 CFU‐Fs/culture), and patients with osteoporosis (129 ± 13 CFU‐Fs/culture; p= 0.20) was found. Average CFU‐F size and cell density per colony were similar in the three groups. Neither the percentage of ALP+CFU‐Fs (66 ± 6%, 65 ± 7%, and 72 ± 4% for young individuals, old individuals, and patients with osteoporosis, respectively) nor the percentage of ALP+cells per culture (34 ± 5%, 40 ± 6%, and 41 ± 4%) differed between groups. Finally, mineralized matrix formation was similar in young individuals, old individuals, and patients with osteoporosis. Our study shows that the number and proliferative capacity of osteoprogenitor cells are maintained during aging and in patients with osteoporosis and that other mechanisms must be responsible for the defective osteoblast (OB) functions observed in these conditions.

Wheat bran was mixed with broken rice to develop nutritionally balanced extruded crisp snacks for human consumption. The inclusion of wheat bran enhanced the content of nutrients such as calcium, phosphorus, iron, copper, thiamine, riboflavin, lysine and also of antinutrients like phytic phosphorus and trypsin inhibitor. Extrusion cooking decreased the content of thiamine, riboflavin and lysine. The degradation of phytic phosphorus and inactivation of trypsin inhibitor had an improving effect on the nutritional quality of the extruded snacks as reflected by higher in vitro digestibility of its proteins.

We tested the ability of N6-furfuryladenine (kinetin) to protect against oxidative and glycoxidative protein damage generated in vitro by sugars and by an iron/ascorbate system. At 50 μM, kinetin was more efficient (82% inhibition) than adenine (49% inhibition) to inhibit the bovine serum albumin (BSA)-pentosidine formation in slow and fast glycation/glycoxidation models. Kinetin also inhibited the formation of BSA-carbonyls after oxidation significantly more than adenine did. However both compounds inhibited the advanced glycation end product (AGE) formation to the same extent (59–68% inhibition). At 200 μM, kinetin but not adenine, limited the aggregation of BSA during glycation. These data suggest that kinetin is a strong inhibitor of oxidative and glycoxidative protein-damage generated in vitro.

N6-Furfuryladenine (kinetin) has been shown to have anti-ageing effects on several different systems including plants, human cells in culture, and fruitflies. Since most of the experimental data point toward kinetin acting as an antioxidant both in vitro and in vivo, and since much evidence supporting a causal role of oxidative damage in ageing is accumulating, we tested the antioxidant properties of kinetin directly. Using 8-oxo-2′deoxyguanosine (8-oxo-dG) in calf thymus DNA as a marker for oxidative damage, we demonstrate that kinetin significantly (P < 0.005) protects the DNA against oxidative damage mediated by the Fenton reaction. Kinetin inhibited 8-oxo-dG formation in a dose-dependent manner with a maximum of 50% protection observed at 100 μM kinetin.

Our survival and the physical quality of life depends upon an efficient functioning of various maintenance and repair processes. This complex network of the so-called longevity assurance processes is composed of several genes, termed vitagenes. The homeodynamic property of living systems is a function of such a vitagene network. Because aging is characterized by the failure of homeodynamics, a decreased efficiency and accuracy of the vitagene network can transmutate it into a gerontogene network. It is not clear how various components of the vitagene network operate and influence each other in a concordant or a discordant manner. Experimental strategies through which this transmutation of vitagenes into virtual gerontogenes may be elucidated include induction of molecular damage, antisense intervention, and genetic screening for varied efficiencies of the members of the vitagene family. A reversal of this approach by maintaining or recovering the activity of vitagenes will lead to a delay of aging, a decreased occurrence of age-related diseases, and a prolongation of a healthy life span.

Monitoring of performance of wastewater treatment systems of an effluent treatment plant is a routine process. However, monitoring is not an easy process when storm water is mixed with wastewater. This is because the mixed water runoff varies significantly in physico-chemical properties unlike in the case of wastewater alone. The present work evaluates impact of storm water runoff on existing sewage treatment plant situated in an industrial township. Significant dilution effect is observed during monsoon period (June-September) in the influent and effluent characteristics of sewage. The estimated excess runoff water during these months is mainly due to the rainfall in the region and due to absence of proper control or design for collection of storm water, thereby avoiding the discharge of the storm water into the treatment plant. This has resulted in the reduction of BOD, COD, total nitrogen and total phosphorus, thus decreasing the efficiency of gas generation.

Kinetin, a cytokinin plant growth hormone, retards senescence in plants, delays aging in human cells in culture, slows down development of insects and prolongs their lifespan. We have now observed that the increased longevity of Kn‐fed Zaprionus fruitflies was accompanied by an increase in the specific activity of catalase during developmental stages and in adult insects. In addition, the egg laying capacity of Kn‐fed fruitflies was reduced drastically as compared with those kept on a normal diet. These results support the view that improved maintenance of the soma and prolongation of its life is achieved at the cost of decreased reproductive activity.

The effects of repetitive mild heat shock (30 min, 41° C) on growth and various cellular and biochemical characteristics of human skin fibroblasts undergoing ageing in vitro were analysed. Human skin ceils not only tolerated more than 30 repeated heat shocks throughout their replicative lifespan, but also maintained several characteristics of young cells until late in life. Whereas the growth rates, population doubling rates, and cumulative population doubling levels achieved in vitro remained unaffected, age‐related changes in cellular morphology, cell size, cytoskeletal organisation, autofluorescence and neutral β‐galactosidase activity were significantly slowed down by repeated mild heat shock. These hormesis‐like effects of stress‐induced defence processes can be useful to elucidate the role of maintenance and repair mechanisms in ageing.

The view that the life span of an organism is intrinsically limited and is largely species‐specific necessarily involves certain notions of genetic elements of regulation. The term gerontogenes refers to any such genetic elements that are involved in the regulation of aging and life span. The existence of genes for programmed aging is generally discounted on the basis of evolutionary arguments against the notion of the adaptive nature of aging. It is suggested here that the concept of gerontogenes be linked with the idea of genes involved in homeostasis and longevity assurance, which is not contradictory to the nonadaptive nature of aging. Because these genes were not originally selected as real genes for aging, their involvement in aging is an emergent property making them virtual gerontogenes. Some experimental evidence is available that suggests that sets of genes involved in the maintenance and repair of various cellular functions are the primary candidates qualifying as virtual gerontogenes.—Rattan, S. I. S. Gerontogenes: real or virtual? FASEB J.9, 284–286 (1995)

Interannual sea level anomalies (SLA), and the related thermocline variations, along the west coast of India (WCI) strongly impact the ecosystems, fisheries, and potentially the monsoon rainfall. Here we investigate the mechanisms driving the WCI interannual SLA using a linear continuously stratified ocean model, which realistically simulates the leading northern Indian Ocean SLA mode associated with the Indian Ocean Dipole (IOD). During, for example, positive IOD events, easterly wind anomalies near Sri Lanka in late summer and fall force downwelling coastal Kelvin waves, which induce positive WCI SLA within days. Meanwhile, equatorial easterlies force upwelling Kelvin waves that travel to WCI through the Bay of Bengal coastal waveguide. Part of this opposite signal also transits slowly through the Bay of Bengal interior as Rossby waves, eventually yielding negative SLA along the WCI in winter. The WCI SLA thus shifts from positive in fall to negative in winter during positive IOD events. The Indian Ocean Dipole (IOD) is the leading mode of Indian Ocean climate variability and is associated with anomalous winds over the equatorial Indian Ocean. A recent work has demonstrated that IOD events could strengthen or inhibit the upwelling of poorly oxygenated waters along the west coast of India (WCI). Such an upwelling impacts oxygen distribution in the upper layers and can thus have adverse effects on ecosystem and fisheries. Here we explain the mechanisms linking the IOD to upwelling along the WCI. IOD zonal winds in the central equatorial Indian Ocean produce two opposite signals on WCI. One that travels fast, directly up the WCI during summer and fall. But another opposite‐polarity signal follows equator and Bay of Bengal rim—a part of which transits slowly through the Bay of Bengal interior, eventually reaching the WCI and flipping the sign of sea level anomalies there in winter. Positive Indian Ocean Dipoles induce positive (negative) sea level anomalies in boreal fall (winter) along the west coast of IndiaFall easterly wind anomalies near Sri Lanka force downwelling coastal Kelvin waves that travel quickly to the west coast of IndiaFall eastern equatorial upwelling signals travel more slowly through the interior Bay of Bengal, reaching the Indian west coast in winter

Focuses on the strategy used by the Minnesota city of Minneapolis to address the issue of urban flooding. Severity, economic impact and consequences of the flooding of the city in 1997; Content and goal of the 'Flood '97' report developed by the city; Improvements done on the storm sewer model used in the city.

Aging is characterized by a stochastic accumulation of molecular damage, progressive failure of maintenance and repair, and consequent onset of age-related diseases. Applying hormesis in aging research and therapy is based on the principle of stimulation of maintenance and repair pathways by repeated exposure to mild stress. In a series of experimental studies we have shown that repetitive mild heat stress has anti-aging hormetic effects on growth and various other cellular and biochemical characteristics of human skin fibroblasts undergoing aging in vitro. These effects include the maintenance of stress protein profiles, reduction in the accumulation of oxidatively and glycoxidatively damaged proteins, stimulation of the proteasomal activities for the degradation of abnormal proteins, improved cellular resistance to ethanol, hydrogenperoxide and ultraviolet-B rays, and enhanced levels of various antioxidant enzymes. Anti-aging hormetic effects of mild heat shock appear to be facilitated by reducing protein damage and protein aggregation by activating internal antioxidant, repair and degradation processes.