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Radiative Heating of an Ice-Free Arctic Ocean
During recent decades, there has been dramatic Arctic sea ice retreat. This has reduced the top-of-atmosphere albedo, adding more solar energy to the climate system. There is substantial uncertainty regarding how much ice retreat and associated solar heating will occur in the future. This is relevant to future climate projections, including the timescale for reaching global warming stabilization targets. Here we use satellite observations to estimate the amount of solar energy that would be added in the worst-case scenario of a complete disappearance of Arctic sea ice throughout the sunlit part of the year. Assuming constant cloudiness, we calculate a global radiative heating of 0.71 W/m2 relative to the 1979 baseline state. This is equivalent to the effect of one trillion tons of CO2 emissions. These results suggest that the additional heating due to complete Arctic sea ice loss would hasten global warming by an estimated 25 years
Thermal energy storage systems using fluidized bed heat exchangers
The viability of using fluidized bed heat exchangers (FBHX) for thermal energy storage (TES) in applications with potential for waste heat recovery was investigated. Of the candidate applications screened, cement plant rotary kilns and steel plant electric arc furnaces were identified, via the chosen selection criteria, as having the best potential for successful use of FBHX/TES system. A computer model of the FBHX/TES systems was developed and the technical feasibility of the two selected applications was verified. Economic and tradeoff evaluations in progress for final optimization of the systems and selection of the most promising system for further concept validation are described
Biochemical & histochemical changes relating to fibrosis following, infection with Mycobacterium tuberculosis in the guineapig
Guineapigs infected with M. tuberculosis were studied for pammeters relating to fibrosis following infection.
The infected animals were followed up to a period of 44 wk and the changes that occurred in the lung, liver and
spleen were studied. Corresponding tissues from animals injected with bleomycin, an anti-mitotic drug which
has the ability to produce pulmonary fibrosis, served as positive controls. Tissue collagen, elastin and hexosamines
were estimated biochemically. The presence of granuloma and stainable collagen in paraffin sections of these
tissues was also studied. Establishment of the infection was assessed bacteriologically by culturing the viable
organisms from the spleen. It was observed that a self-limiting infection was established in the guineapigs and
none of the animals died of the infection. In the infected animals, collagen, elastin and hexosamines showed an
initial decrease followed by an increase. While the elastin and the hexosamine levels returned to the basal levels
in all the three organs, collagen levels increased in the lung and were comparable to those of the bleomycin
control. Collagen stainable by Van Gieson’s method was found to be increased in the lung from the 4th wk
onwards. The present report indicates the potential of adopting this system for studying mechanisms of
fibrogenesis in tuberculous infection
Observation of a 2D Bose-gas: from thermal to quasi-condensate to superfluid
We present experimental results on a Bose gas in a quasi-2D geometry near the
Berezinskii, Kosterlitz and Thouless (BKT) transition temperature. By measuring
the density profile, \textit{in situ} and after time of flight, and the
coherence length, we identify different states of the gas. In particular, we
observe that the gas develops a bimodal distribution without long range order.
In this state, the gas presents a longer coherence length than the thermal
cloud; it is quasi-condensed but is not superfluid. Experimental evidence
indicates that we observe the superfluid transition (BKT transition).Comment: 5 pages, 6 figure
STRUCTURAL AND FUNCTIONAL IMPACT OF G2032R MUTATION IN ROS1 – A THEORETICAL PERSPECTIVE
Objective: Drug resistance is an imperative issue in the treatment of patients with lung cancer. In this work, investigation of the drug resistance mechanism of G2032R mutation in ROS1 is carried out using computational simulation techniques.Methods: Molecular docking and molecular dynamics (MD) simulation approach have been utilized to uncover the mechanism behind crizotinib resistance in ROS1 at a molecular level. Normal mode analysis was carried out using ElNemo server which examines the movements and conformational changes in the protein structure. ArgusLab, PEARLS, and Autodock were employed for the docking analysis, whereas GROMACS package 4.5.3 was used for MD simulation approach.Results: The results from our analysis indicates that wild-type ROS1 (Protein Data Bank Code 3ZBF) could be more crucial for the crizotinib binding as it indicates largest binding affinity, minimum number of H-bonds, and higher flexibility than mutant-type ROS1. Moreover, the theoretical basis for the cause of drug insensitivity is the differences in the electrostatic properties of binding site residues between the wild and mutant ROS1 structures. Our analysis theoretically suggests that E-2027 is a key residue responsible for the ROS1 drug selectivity.Conclusion: Molecular docking and MD simulation results provide an explanation of the resistance caused by G2032R and may give a key clue for the drug design to encounter drug resistance.Â
A sequential study of circulating immune complexes, complement mediated IC solubilisation and immunoglobulins in borderline tuberculoid patients with and without reactions
Sequential estimates of the levels of circulating immune complexes (CIC), complement
catabolic fragment C3d, complement-mediated immune complex solubilization (CMS) and
immunoglobulins were made in 24 newly diagnosed patients with borderline tuberculoid
leprosy over a 20 month period after initiation of chemotherapy.
Fourteen of these patients had not suffered from reversal reactions either at the time
of presentation or during the follow-up period. The levels of CIC were elevated in them
from the third to the eleventh month after starting chemotherapy and immunoglobulin G
(IgG) levels were elevated upto eight months. The concentrations of C3d and
immunoglobulins A (IgA) and M (IgM) were normal in these patients.
The other ten patients had reversal reaction at the time of diagnosis which subsided
by the third month after starting treatment. They did not have reversal reactions later. The
levels of CIC and IgG were elevated and those of CMS were depressed throughout the
study period. Serum C3d level was initially elevated but came down to normal by the third
month while IgA and IgM levels were within normal limits.
The relevance of these findings to the genesis of reversal reaction is discussed in this
communication
Ensemble quantum-information processing by NMR: implementation of gates and the creation of pseudopure states using dipolar coupled spins as qubits
Quantum-information processing is carried out using dipolar coupled spins and high-resolution nuclear magnetic resonance (NMR). The systems chosen are the dipolar coupled methyl protons of CH3CN partially oriented in a liquid crystalline matrix yielding a two-qubit system and dipolar coupled 13C and methyl protons of 13CH3CN also partially oriented in the liquid crystalline matrix, yielding a three-qubit system. The dipolar coupled protons of oriented CH3 group are chemically and magnetically identical and their eigenstates can be divided into a set of quartet states (symmetric A) and a pair of doublet (E) states. We describe here a method for selectively retaining the magnetization of the symmetric states, yielding two and three qubit systems. We create pseudopure states using single-quantum-transition selective pulses and implement two- and three-qubit gates using one- and two-dimensional NMR
Toward quantum information processing by nuclear magnetic resonance: pseudopure states and logical operations using selective pulses on an oriented spin <SUP>3/2</SUP> nucleus
Nuclear magnetic resonance spectroscopy has demonstrated significant experimental progress toward the development of quantum computations. The developments so far have taken place mainly through the use of spin ½ nuclei. In this paper we describe the use of a spin math nucleus, oriented in a liquid crystal matrix for the creation of pseudopure states and the implementation of a complete set of two-qubit reversible logic gates using single-quantum transition-selective pulses, extending the range of practice of NMR toward quantum computation
Latitude gradient in aerosol properties across the Inter Tropical Convergence Zone: results from the joint Indo-US study onboard Sagar Kanya
As part of the Indian Ocean Experiment (INDOEX) Intensive Field Phase (IFP), a cruise by ORV Sagar Kanya was conducted in the Arabian Sea and the Indian Ocean from 20 January to 12 March 1999. Measurements on aerosol properties such as optical depth, mass concentration, size distribution, scattering and absorption coefficients were measured using instruments such as sun-photometer, quartz crystal microbalance, nephelometer and particle-soot absorption photometer. One of the important findings is the large north-south asymmetry in the aerosol characteristics. Aerosol optical depth values were very high, exceeding 0.4, close to the west coast of India and the Arabian Sea, which is greater than by a factor of 4 or more, compared to the values south of the ITCZ. The wavelength exponent α, is found to be in the range of 1.3 to 1.7 in the high optical depth region and is in the range of 0.5 to 0.7 over the pristine region. Aerosol mass concentration data show that the nucleation mode aerosols (radius < 0.1 µm) are systematically higher over the Arabian Sea, with values ranging from 20 to 50 µg/m3. Correlating the aerosol mass with the scattering coefficient, we get a scattering to mass concentration ratio of 2.27 m2/g, for the Arabian Sea region, which is in between the values reported by other workers, 3.3 m2/g for the continent and 1.67 m2/g for the marine regions, elsewhere in the world. The single scattering albedo, ω derived from the scattering and absorption data, is around 0.9 for aerosols found over the Arabian Sea, while near the coastal regions the values are as low as 0.8. Low ω and high optical depth found in the coastal region and Arabian Sea indicate large absorption by aerosols. The results undoubtedly show a large spatial difference in aerosol characteristics between north and south of the ITCZ which could lead to a large asymmetry in aerosol radiative forcing between the two regions
Partial-Transfer Absorption Imaging: A versatile technique for optimal imaging of ultracold gases
Partial-transfer absorption imaging is a tool that enables optimal imaging of
atomic clouds for a wide range of optical depths. In contrast to standard
absorption imaging, the technique can be minimally-destructive and can be used
to obtain multiple successive images of the same sample. The technique involves
transferring a small fraction of the sample from an initial internal atomic
state to an auxiliary state and subsequently imaging that fraction absorptively
on a cycling transition. The atoms remaining in the initial state are
essentially unaffected. We demonstrate the technique, discuss its
applicability, and compare its performance as a minimally-destructive technique
to that of phase-contrast imaging.Comment: 10 pages, 5 figures, submitted to Review of Scientific Instrument
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