A comprehensive size‐segregated characterization of the chemical properties (water‐soluble inorganic fraction) of the sea‐salt aerosol originated from the surf zone at the land‐ocean boundary of ...Sundarban Mangrove forest, NE coast of Bay of Bengal, and an analysis of the relevant meteorological parameters revealed how the combined effect of anthropogenic gases and aerosol advected to the virgin mangrove forest and micrometeorological conditions could change the marine character of the aerosol before the onset of SW monsoon. The average aerosol mass concentration was 99.94 ± 41.9 μg m−3 with production rate of 0.19 μg m−2 s−1 (during January) to 4.29 μg m−2 s−1 (during April) and dry deposition rate of 0.019 μg m−2 s−1 (during January) to 13.21 μg m−2 s−1 (during June). 72.35% of the total aerosol mass was leachable by water, and relatively large concentrations of phosphorus were observed. More chloride depletion from the coarse (2.0 < dp < 10 μm) and nucleation (dp < 0.4 μm) modes compared to the accumulation mode (0.4 < dp < 2.0 μm) was observed in winter (Cl/Na = 0.6023 ± 0.1798), and a reverse trend was observed in summer (Cl/Na = 0.644 ± 0.262). A significant positive correlation was obtained for chloride loss with non‐sea‐sulphate and nitrate for particles > 2.0 μm. Distributions of Na+, K+, Ca2+, Mg2+, NH4+, Cl−, NO2−, NO3−, SO42−, and PO43− in different size modes were considered to collate their source apportionment. The proximity of Calcutta and Haldia metropolis to the mangrove forest could influence the forest air quality and depositional processes.
Retinoblastoma Mehta, M; Sethi, S; Pushker, N ...
Singapore medical journal,
02/2012, Volume:
53, Issue:
2
Journal Article
Peer reviewed
Retinoblastoma is the most common intraocular malignancy in children and one of the very few life-threatening ophthalmic conditions. Genetically, the disease may be heritable or non-heritable. It can ...have unilateral or bilateral involvement and can present either sporadically or with a positive family history. Leukocoria and strabismus are the most common presentations. Diagnosis is made by indirect ophthalmoscopy aided by imaging techniques. Multidisciplinary management is aimed at saving lives, salvaging the globe and maintaining good vision. The use of neoadjuvant chemotherapy and focal treatments, such as cryotherapy, laser photocoagulation, transpupillary thermotherapy, brachytherapy and periocular chemotherapy, form the mainstay of globe preserving treatment in retinoblastoma. In developing countries, retinoblastoma is unfortunately accompanied by a high mortality rate due to delayed diagnosis made at advanced stages of the disease. Early diagnosis and timely management are vital for a good prognosis.
In the recent past a few important open problems such as those involving developing polynomial-time iterative algorithms for solving linear programs in both integer and real number models and for ...testing and generating primes have been solved. There are still several problems we have not found solutions over decades/centuries. Problems such as those involving (i) devising a deterministic noniterative polynomial-time algorithm for linear programs, (ii) deciding a priori all required fail-proof prime bases for errorfree computations for linear systems and linear optimization, (iii) determining computational complexities in some deterministic algorithms, (iv) designing algorithms with the lowest possible bound of complexity for matrix multiplications, (v) developing a polynomial-time deterministic algorithm for computing the error-bounds in an error-free computation, (vi) verification of the solution of some nonlinear optimization problems in polynomial time, (vii) obtaining the error-bounds in the solution of some linear/nonlinear problems when solved probabilistically are open problems. The solution of these open problems has the potential to revolutionize the whole area of computational mathematics and science as well as super-/grid-computing. We present here some of these open problems precisely along with the related discussions.
The fast-growing networked computing devices create many distributed systems and generate new signals on a large scale. Typical applications include peer-to-peer streaming of multimedia data, crowd- ...sourcing, and measurement by sensor networks. Therefore, the massive amount of networked data is a form of big data, calling for new data structures and algorithms different from classical ones suitable for small data sizes. We consider a vital data format for recording information from networked distributed systems: signals on graphs. A significant concern is to protect the privacy of large scales of signals when processed at third parties, such as cloud data centers. A de-facto solution is to outsource encrypted data before they arrive at the third-parties. We propose a novel and efficient privacy-protected outsourced denoising algorithm based on the information-theoretic secure multi-party computation (secure MPC). Among the operations of signals on graphs, denoising is useful before further meaningful processing can occur. We experiment with our algorithms in a popular platform of secure MPC and compare it with Paillier's homomorphic encryption approach. The results demonstrate a better efficiency of our approach.
Nonlinear dynamics of a thermal pulse combustor was investigated using a coupled fourth order lumped combustor model. The effects of optically thin radiation from the combustor gases to the wall are ...also investigated. The system response changes from steady combustion to extinction through oscillatory combustion as the wall temperature is lowered. The qualitative results suggest a transition to chaos through a period-doubling route prior to extinction. The presence of chaos is also confirmed by quantitative measures like correlation dimension and Lyapunov exponent. The system dynamics is qualitatively similar in presence and absence of radiation. However, inclusion of radiative heat loss leads to extinction at higher temperatures and also increases the predicted range of wall temperatures for which limit cycle behaviour is obtained. A measure for monitoring the proximity of the system to extinction has been developed using the time series data.
It's hip to be square: The reaction of amidinato chlorosilylene (PhC(NtBu)2SiCl) with adamantyl phosphaalkyne and white phosphorus affords the formation of Si‐C‐Si‐P and Si‐P‐Si‐P (see picture) ...four‐membered rings. Both compounds were characterized by single‐crystal X‐ray studies and by solution and solid‐state NMR spectroscopy. DFT calculations elucidated the bonding situation.
To predict residual and thermal stresses which occur during water quenching of solid cylindrical rod and ring cross-sectioned steel tubes, a finite element technique has been used. The variations of ...residual stresses on different surfaces and cross-sections, e.g. in the radial, axial and tangential directions have been examined, and the effect of internal diameter of tubes on residual stress was investigated. The results show that the residual stresses act as a compressive force along the cooling surface and then by moving away from the surface begin to decrease and reverse their sign, near the centre of the cylinder are subjected to tensile stresses. Because of the reversal of the sign of stress, the effective stress goes to a minimum at some distance from the frontal surface and this may be vital since lower plastic deformation may cause cracking failure. As in solid cylinder, in cylindrical tubes also, the frontal and the upper cooling surface has significant effect on the stress distribution. From the comparison of the residual stress distributions of solid cylinder and cylindrical tubes and using their individual stress maps it was seen that they vary considerably along different cooling surfaces, especially at the frontal surface.
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