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Cirrus clouds are highly reflective clouds that play an important role in the atmospheric radiative balance and contribute to climate change. We present the seasonal distribution of cirrus cloud occurrence, characteristics and evolution over a coastal station (Goa, 15.4°N, 73.8°E, 40 m above MSL) in India using ground-based micro pulse lidar and radiosonde observations from July 2013 to June 2015. The frequency of cirrus occurrence was approximately 44%, 33%, 17% and 6% in winter (JF), premonsoon (MAM), southwest monsoon (JJAS) and postmonsoon season (OND), respectively. Thicker cirrus was more frequent in September, with an average value of > 1.7 ± 0.89 km. The frequency of cirrus descent occurs almost similarly in monsoon and postmonsoon (42% and 43% respectively). Two extreme cirrus descending cases were observed during the monsoon: (1) on 22 August 2014 with a displacement of 9.6 km from the initial height of 14 km with a descending rate and geometrical thickness of 0.4 ms−1 and 1.5 km, respectively, and (2) on 14 September 2013 with a displacement of 7.8 km with descending rate and thickness of 0.2 ms−1 and 2.3 km respectively. Relatively high humidity (> 60%) and low (< − 20 °C) ambient temperature caused thick cirrus formation in September 2013. However, during August 2014 event, relatively thinner cirrus was observed, and the same is attributed to lower humidity conditions (45 to 60%). The wind shear associated with the tropical easterly jet (TEJ) plays a major role in cirrus displacement by modifying their vertical velocity. The positive and negative vertical velocity fields cause cirrus to have a descending shape. The gradual descending pattern of cirrus is moving parallel to the vertical velocity contour, while the rapid descending in 2014 was mainly due to the occurrence of cirrus perpendicular to the velocity contour. Overall, this study highlights the descending nature of cirrus clouds over a coastal station in India, which can impact surface radiative characteristics. [ABSTRACT FROM AUTHOR]

Atmospheric mineral dust is derived from arid/semi-arid region, undergoes long-range transport, and can impact surface biogeochemical processes in the pristine marine region. This study reports fluxes of mineral dust (wet and dry deposition), their clay mineralogy, and associated seasonal variability over the Northeastern Arabian Sea. Dust sources are assessed using mineral composition and their ratios as well as satellite retrievals during 2012–2015. The average wet deposition flux (293 mg m−2 day−1) of mineral dust is three times higher than dry deposition flux (96 mg m−2 day−1). A clear distinction is observed in the mineral composition of wet and dry deposited dust with smectite and palygorskite being dominant during the wet period and illite and chlorite being dominant during the dry period. Mineralogical composition and their ratios indicate that major dust sources to the Northeastern Arabian Sea are from northeast Africa, Arabian Peninsula, and southwest Asia. These observations are corroborated with the satellite retrievals, aerosol optical depth, and back trajectory analyses. [ABSTRACT FROM AUTHOR]

The selection of text features is a fundamental task and plays an important role in digital document analysis. Conventional methods in text feature extraction necessitate indigenous features. Obtaining an efficient feature is an extensive process, but a new and real-time representation of features in text data is a challenging task. Deep learning is making inroads in digital document mining. A significant distinction between deep learning and traditional methods is that deep learning learns features in a digital document in an automatic manner. In this paper, logistic regression and deep dependency parsing (LR-DDP) methods are proposed. The logistic regression token generation model generates robust tokens by means of Napierian grammar. With the robust generated tokens, a deep transition-based dependency parsing using duplex long short-term memory is designed. Experimental results demonstrate that our dependency parser achieves comparable performance in terms of digital document parsing accuracy, parsing time and overhead when compared to existing methods. Hence, these methods are found to be computationally efficient and accurate. [ABSTRACT FROM AUTHOR]

The observed trend in Earth's energy imbalance (TEEI), a measure of the acceleration of heat uptake by the planet, is a fundamental indicator of perturbations to climate. Satellite observations (2001–2020) reveal a significant positive globally-averaged TEEI of 0.38 ± 0.24 Wm−2decade−1, but the contributing drivers have yet to be understood. Using climate model simulations, we show that it is exceptionally unlikely (<1% probability) that this trend can be explained by internal variability. Instead, TEEI is achieved only upon accounting for the increase in anthropogenic radiative forcing and the associated climate response. TEEI is driven by a large decrease in reflected solar radiation and a small increase in emitted infrared radiation. This is because recent changes in forcing and feedbacks are additive in the solar spectrum, while being nearly offset by each other in the infrared. We conclude that the satellite record provides clear evidence of a human-influenced climate system. Satellite observations reveal a significant positive trend in Earth's energy imbalance, but the contributing drivers have yet to be understood. Here, the authors show that it is exceptionally unlikely that this trend can be explained by internal variability; instead, anthropogenic forcing and feedbacks cause the trend. [ABSTRACT FROM AUTHOR]

Purpose: Metabolic alterations underlie many pathophysiological conditions, and their understanding is critical for the development of novel therapies. Although the assessment of metabolic changes in vivo has been historically challenging, recent developments in molecular imaging have allowed us to study novel metabolic research concepts directly in the living subject, bringing us closer to patients. However, in many instances, there is need for sensors that are in close proximity to the organ under investigation, for example to study vascular metabolism. Methods: In this study, we developed and validated a metabolic detection platform directly in the living subject under an inflammatory condition. The signal collected by a scintillating fiber is amplified using a photomultiplier tube and decodified by an in-house tunable analysis platform. For in vivo testing, we based our experiments on the metabolic characteristics of macrophages, cells closely linked to inflammation and avid for glucose and its analog 18F-fluorodeoxyglucose (18F-FDG). The sensor was validated in New Zealand rabbits, in which inflammation was induced by either a) high cholesterol (HC) diet for 16 weeks or b) vascular balloon endothelial denudation followed by HC diet. Results: There was no difference in weight, hemodynamics, blood pressure, or heart rate between the groups. Vascular inflammation was detected by the metabolic sensor (Inflammation: 0.60 ± 0.03 AU vs. control: 0.48 ± 0.03 AU, p = 0.01), even though no significant inflammation/atherosclerosis was detected by intravascular ultrasound, underscoring the high sensitivity of the system. These findings were confirmed by the presence of macrophages on ex vivo aortic tissue staining. Conclusion: In this study, we validated a tunable very sensitive metabolic sensor platform that can be used for the detection of vascular metabolism, such as inflammation. This sensor can be used not only for the detection of macrophage activity but, with alternative probes, it could allow the detection of other pathophysiological processes. [ABSTRACT FROM AUTHOR]

Water supply reservoir management is based on long-term management policies which depend on customer demands and seasonal hydrologic changes. However, increasing frequency and intensity of precipitation events is necessitating the short-term management of such reservoirs to reduce downstream flooding. Operational management of reservoirs at hourly/daily timescales is challenging due to the uncertainty associated with the inflow forecasts and the volumes in the reservoir. We present an ensemble-based streamflow prediction and optimization framework consisting of a regional scale hydrologic model forced with ensemble precipitation inputs to obtain probabilistic inflows to the reservoir. A multi-objective dynamic programming model was used to obtain optimized release strategies accounting for the inflow uncertainties. The proposed framework was evaluated at a water supply reservoir in the Hackensack River basin in New Jersey during Hurricanes Irene and Sandy. Hurricane Irene resulted in the overtopping of the dam despite releases made in anticipation of the event and resulted in severe downstream flooding. Hurricane Sandy was characterized by low rainfall, however, raised significant concerns of flooding given the nature of the event. The improvement in NSE for the Hurricane Irene inflows from 0.5 to 0.76 and reduction of the spread of PBIAS with decreasing lead times resulted in improvements in the forecast informed releases. This study provides perspectives on the benefits of the proposed forecasting and optimization framework in reducing the decision making burden on the operator by providing the uncertainties associated with the inflows, releases and the water levels in the reservoir. [ABSTRACT FROM AUTHOR]

Ependymomas are common childhood brain tumours that occur throughout the nervous system, but are most common in the paediatric hindbrain. Current standard therapy comprises surgery and radiation, but not cytotoxic chemotherapy as it does not further increase survival. Whole-genome and whole-exome sequencing of 47 hindbrain ependymomas reveals an extremely low mutation rate, and zero significant recurrent somatic single nucleotide variants. Although devoid of recurrent single nucleotide variants and focal copy number aberrations, poor-prognosis hindbrain ependymomas exhibit a CpG island methylator phenotype. Transcriptional silencing driven by CpG methylation converges exclusively on targets of the Polycomb repressive complex 2 which represses expression of differentiation genes through trimethylation of H3K27. CpG island methylator phenotype-positive hindbrain ependymomas are responsive to clinical drugs that target either DNA or H3K27 methylation both in vitro and in vivo. We conclude that epigenetic modifiers are the first rational therapeutic candidates for this deadly malignancy, which is epigenetically deregulated but genetically bland. [ABSTRACT FROM AUTHOR]

Shell weights of planktonic foraminifera species Globigerinoides ruber in the size range of 300-355 $\upmu$m were measured from sediment traps in the western and eastern Arabian Sea which represent upwelling and non-upwelling conditions respectively. In the Western Arabian Sea Trap (WAST), G. ruber flux ranged from 33.3 to 437.3 #/m/day and shell weights ranged from 6.7 to 14.2 $\upmu$g. Whereas, in the Eastern Arabian Sea Trap (EAST), flux ranged from 0.7 to 164.6 #/m/day and shell weights ranged from 10.4 to 14.8 $\upmu$g. Shell weights of G. ruber versus flux showed significant correlation at both the sites which reveals that shell calcification mainly depends on optimal growth conditions. Though the WAST and EAST location have distinct difference in pCO and sea surface temperature (SST), the shell weights of G. ruber are similar in these two regions which suggest that surface water pCO and SST do not show dominant influence on shell calcification on a seasonal timescale. [ABSTRACT FROM AUTHOR]

Leptospirosis is one of the diseases with economic impact, so its diagnosis and serosurveillance are very important for any control program. Many tests have been used in the field as screening tests of leptospirosis. The aim of this study was to evaluate the efficacy of combined recombinant antigens (rLipL41 + rLipL32) for serodiagnosis of canine leptospirosis and to compare the efficacy of IgG Enzyme linked immunosorbent assay and Latex agglutination test with standard MAT. A total of 533 canine serum samples were subjected to IgG-ELISA and LAT using recombinant LipL41 and LipL32 antigens in a single and in a combinations which were compared with standard MAT. The potential diagnostic cocktails of combined recombinant antigens (rLipL31 + rLipL41) developed in this study showed higher sensitivity and specificity in IgG ELISA and LAT (94.84, 88.50%; 98.21, 97.7%) when compared to the use of single recombinant antigen in this study. Results indicated that the both assays can be easily performed, and avoids the risk of infection in laboratory workers, and it seems to be a practical and suitable tool for serodiagnosis of leptospirosis. [ABSTRACT FROM AUTHOR]

Catalysts of general formula, MoVAlO x were prepared with the initial elemental composition of 1:0.34:0.167 (Mo:V:Al) at a pH value in the range of 1–4. The elemental analysis showed that the final composition of the catalysts is pH dependant. The performance of the catalysts was tested for selective oxidation of ethane to give ethylene and acetic acid. While all of them were active for ethane oxidation with a moderate conversion, the catalyst prepared at pH 2 showed a highest activity with 23% ethane conversion and a combined selectivity of 80.6% to ethylene and acetic acid. The catalyst prepared at pH 4 was least selective to ethylene and acetic acid. Various techniques like powder XRD, SEM, Raman, UV–Vis and EPR were used to characterize the catalysts and to identify the active phases responsible for the selective oxidation of ethane. The powder XRD data showed that the catalysts prepared at pH 1 and 2 contain mainly of MoO3 and MoV2O8 along with traces of Mo4O11. The amount of MoO3 was slightly higher in the catalyst prepared at pH 1. However, the catalyst prepared at pH 3 contains mainly of MoV2O8 with no trace of MoO3. The catalyst prepared at pH 4 showed V2O5 as the major phase along with MoVAlO4 phase. The Raman data corroborated the XRD results. EPR and UV–Vis studies indicated the presence of traces of V4+ in pH 1 and 2 catalysts and significant amount of Mo5+ in all the catalysts. Thus, the high activity and selectivity to ethylene and acetic acid are attributed to the presence of MoV2O8 phase and other reduced species like Mo4O11 phase supported on MoO3. The presence of V and Mo ions in a partially reduced form seems to play a crucial role in the selective oxidation of ethane. [ABSTRACT FROM AUTHOR]

Zirconium-containing medium-pore, Al-free molecular sieves (Si/Zr molar ratios > 50) with MFI structure have been synthesized both in alkaline and HF/CH3NH2 medium. The samples synthesized in HF/CH3NH2 medium exhibit a high crystallinity, bigger particle size, lower surface area and lower catalytic activity in the hydroxylation of phenol as compared to those synthesized in alkaline medium. An expansion in unit cell volume (XRD), an absorption at 965 cm-1 (FTIR) and at 212 nm (UV-Visible) as well as the catalytic activity data indicate that upto 0.6 zirconium atom per unit cell (Si/Zr=158) could be substituted isomorphously within the silicalite-1 framework. The IR study of adsorbed pyridine has shown that strong Lewis acid and weak Brønsted acid sites exist on all zirconium silicate samples, synthesized in alkaline medium. The relative stability of cluster models representing various possible lattice structures and the ordering of molecular orbitals derived from extended Hückel molecular orbital calculations are discussed to understand the nature of active sites in the zirconium silicates. [ABSTRACT FROM AUTHOR]

The importance of clouds in the upper troposphere (cirrus) for the sensitivity of the Earth's climate e.g., requires that these clouds be modeled accurately in general circulation model (GCM) studies of the atmosphere. Bearing in mind the lack of unambiguous quantitative information on the geographical distribution and properties of high clouds, the simulated distribution of upper tropospheric clouds in a spectral GCM is compared with several satellite-derived data-sets that pertain to high clouds only, for both winter and summer seasons. In the model, clouds are assumed to occupy an entire gridbox whenever the relative humidity exceeds 99%: otherwise the grid box is assumed to be free of cloud. Despite the simplicity of the cloud prediction scheme, the geographical distribution of the maxima in the model's upper tropospheric cloud cover coincides approximately with the regions of the observed maxima in the high cloud amount and their frequency of occurrence (e.g., intertropical convergence zone and the monsoon areas). These areas exhibit a minimum in the outgoing longwave radiation (OLR; Nimbus-7) and are also coincident with regions of heavy precipitation. The model, with its relatively simple cloud formation scheme, appears to capture the principal large-scale features of the tropical convective processes that are evident in the satellite and precipitation datasets, wherein the intense, upward motion is accompanied by condensation and the spreading of thick upper tropospheric layers of high relative humidity and cloudiness in the vicinity of the tropical rainbelt regions. [ABSTRACT FROM AUTHOR]

The stress-strain data of a high-strength low-alloy (HSLA) steel were measured at different temperatures and analyzed in terms of strain-hardening laws proposed by Hollomon,[1] Ludwik,[2] Swift,[3] and Voce.[4] Four methods of analysis, as suggested by Kleemola and Nieminen (K-N),[7] Crussard and Jaoul (C-J),[16] Ramani and Rodriguez (R-R),[11] and Guimarães (G),[15] have been employed. The C-J analysis has been extended to the Voce equation for the first time. The results have been discussed in terms of the linear correlation coefficient and error in the estimation of uniform strain. The Voce equation has been found to describe the flow be-havior most accurately. The observed increase in flow stress in the dynamic strain aging (DSA) range has been explained in terms of temperature-dependent strain-hardening parameters. It has been established that with increase in the value of the Voce strain component, n, the magnitude of the saturation stress approaches that of the ultimate tensile stress. A linear relationship has been established between ultimate tensile stress and saturation stress. [ABSTRACT FROM AUTHOR]

Recent developments in carbon and alloy steels outlined in this paper include those pertaining to low-carbon mild steels, high-strength low-alloy (HSLA) steels, dual-phase steels, low-carbon bainitic steels, ultrahigh strength steels and ferritic stainless steels. The factors that improve the cold-forming characteristics of low carbon sheets and strips are outlined. The physical metallurgy principles governing the ferrite grain refinement in HSLA steels are discussed, pointing out how it can be achieved by the controlled rolling process. The importance of sulphide shape control in imparting the necessary through-thickness ductility in HSLA steels is discussed and the various methods available for inclusion shape control are outlined. Improved formability coupled with adequate strength characterizes the dualphase steels. Among the ultrahigh strength steels, two recent developments, viz. TRIP steels and maraging steels are outlined. It is pointed out how the improved formability of ferritic stainless steels is making them compete with the more expensive austenitic stainless steels. The scope for future developments in these steels is discussed at the end. [ABSTRACT FROM AUTHOR]

Newcastle disease virus (NDV) was isolated from the faeces of seven different species of clinically healthy captive wild birds. All seven NDV isolates were characterized as velogenic, based on the mean death time in embryonated hens' eggs and the intracerebral pathogenicity index in day-old chicks. Three of the isolates were placed in group C1 based on the reactions with monoclonal antibodies. The role of captive wild birds in the epidemiology of Newcastle disease is briefly discussed. [ABSTRACT FROM AUTHOR]

Investigates the role of ozone losses in affecting patterns of temperature change by incorporating the observed increase in stratospheric ozone concentrations from 1979 to 1990 into a general circulation model of the atmosphere.

Determines the radiative forcing of the surface-troposphere system due to the observed decadal ozone losses, and compares it with that due to the increased concentrations of the other main radiatively active gases. Results that suggest that the net decadal contribution of CFCs to the greenhouse climate forcing is substantially less than previously estimated; Details; The Geophysical Fluid Dynamics Laboratory (GFDL); More.

Despite distinct geographic distributions of top-of-the-atmosphere radiative forcing, anthropogenic greenhouse gases and aerosols have been found to produce similar patterns of climate response in atmosphere-and-ocean coupled climate model simulations. Understanding surface energy flux changes, a crucial pathway by which atmospheric forcing is communicated to the ocean, is a vital bridge to explaining the similar full atmosphere-and-ocean responses to these disparate forcings. Here we analyze the fast, atmosphere-driven change in surface energy flux caused by present-day greenhouse gases vs aerosols to elucidate its role in shaping the subsequent slow, coupled response. We find that the surface energy flux response patterns achieve roughly two-thirds of the anti-correlation seen in the fully coupled response, driven by Rossby waves excited by symmetric changes to the land-sea contrast. Our results suggest that atmosphere and land surface processes are capable of achieving substantial within-hemisphere homogenization in the climate response to disparate forcers on fast, societally-relevant timescales. Anthropogenic aerosol and greenhouse gas concentrations are spatially uncorrelated, but the climate response to each shows a similar spatial pattern. Here the authors show that two-thirds of the spatial similarity in the full response manifests through fast-acting atmosphere and land surface processes alone. [ABSTRACT FROM AUTHOR]

Chemical weathering and the ensuing atmospheric carbon dioxide consumption has long been considered to work on geological time periods until recently when some modelling and natural records have shown that the weathering-related CO2 consumption can change at century to glacial-interglacial time scale. Last glacial to interglacial transition period is a best test case to understand the interplay between Pco2-temperature-chemical weathering when a pulse of rapid chemical weathering was initiated. Here we show, from a high resolution 54 ka record from the Andaman Sea in the northern Indian Ocean, that the chemical weathering responds to deglacial to mid-Holocene summer monsoon intensification in the Myanmar watersheds. The multi-proxy data (Al/K, CIA, Rb/Sr, 87Sr/86Sr for degree of weathering and 143Nd/144Nd for provenance) reveal an increase in silicate weathering with initiation of interglacial warm climate at ~17.7 ka followed by a major change at 15.5 ka. Inferred changes in chemical weathering have varied in tandem with the regional monsoonal proxies (δ18Osw-salinity changes of Northern Indian Ocean, effective Asian moisture content and δ18O records of Chinese caves) and are synchronous with changes in summer insolation at 30°N and δ18O of GISP2 implying that chemical weathering was not a later amplifier but worked in tandem with global climate change. [ABSTRACT FROM AUTHOR]

ALP from A. niger is a) P repressible enzyme; b) stimulated by addition of Zn to the growth medium, and c) that EDTA inhibits the enzyme reversibly, which could be restored by addition of Zn and perhaps Mg. This property is in contrast to the enzyme from N. crassa, which is independent of any metal requirement. [ABSTRACT FROM AUTHOR]

Focuses on an article by Rampino and Self in the September 3, 1992 issue of `Nature' that suggests that the massive volcanic eruption at Toba, in the Indian Ocean, 73,500 years ago, may have accelerated the onset of the last ice age by loading the stratosphere with aerosols and shadowing the Earth. Effect of volcanic eruptions on climate; More.