Structural studies of some coordination and organometallic complexes of transition metals

Imperial Users onl

Some estimates of farm-level storage losses of rice in Bangladesh

This paper relates to farm-level storage of Aman (winter) season paddy (unhusked rice) and rice in 1978-79. The estimates are based on work from the first year of the Institute of Development Studies post-harvest research project in Comilla district of Bangladesh. After a description of the causes of loss arising during farm-level storage, the problems of loss measurement and the methods adopted are explained. Estimates of quantitative losses of paddy and parboiled rice, in a variety of different storage structures, are given with a 'best estimate' of average physical loss (2.04 per cent). A factor (1.25) has been calculated to convert the physical loss of paddy to a loss of food, so as to obtain an overall estimate of average food loss (2.43 per cent). The results are briefly discussed with regard to the relative performance of raw and parboiled grain and to possible implications for policies concerned with reducing post-harvest loss

The urban geography of the heart of a city : with special reference to Edinburgh

A city is the expression both of its region and its site. The region calls it into being; the site governs its birth. Thereafter as it glows it exploits the site to serve the region, It increasingly focuses the activities of the region on the site, thus making that site the heart of the region. In most cases it draws the region into a crucial area within the site which becomes the heart of the city. Although the pattern of landuse in the core of the city is due mainly to ecological forces within the city itself to competition for space, to specialisation in function, and to segregation of forms - nevertheless that pattern does reflect wider realities. Therefore a study of the heart of the city might properly begin with that of the general setting and local site

Colorectal carcinoma: nucleosomes, carcinoembryonic antigen and ca 19-9 as apoptotic markers; a comparative study

<p>Abstract</p> <p>Background</p> <p>Colorectal carcinoma is a common and often fatal disease in which methods of early detection and monitoring are essential. The present study was conducted for measuring serum levels of nucleosomes, carcinoembryonic antigen (CEA) and CA 19-9 in patients newly diagnosed with colorectal carcinoma and confirmed by clinicopathological study.</p> <p>Method</p> <p>Thirty subjects were included in the current study: six normal subjects as a control group with mean age (45.6 ± 7.9) and twenty four colorectal carcinoma patients with mean age (46.9 ± 15.6), which were classified pathologically according to the degree of malignant cell differentiation into well differentiated (group I), moderately differentiated (group II) and poorly differentiated (group III). Fasting venous blood samples were collected preoperative.</p> <p>Results</p> <p>The results revealed a significant increase in serum level of nucleosomes in patients with poorly differentiated tumors versus patients with well differentiated tumors (p = 0.041). The levels of CEA and CA19-9 showed no significant increase (p = 0.569 and 0.450, respectively).</p> <p>Conclusion</p> <p>In conclusion, serum level of nucleosomes provides a highly sensitive and specific apoptotic marker for colorectal carcinoma.</p

trans-Bis(3-hy­droxy­pyridine-κN)diiodidoplatinum(II) dimethyl sulfoxide disolvate

In the title compound, [PtI2(C5H5NO)2]·2(CH3)2SO, the PtII ion lies on an inversion center and is coordinated in a slightly distorted square-planar environment by two trans iodide ligands and two pyridine N atoms. In the crystal, complex mol­ecules and solvent dimethyl sulfoxide mol­ecules are linked by inter­molecular O—H⋯O hydrogen bonds

DESIGN, PERFORMANCE ANALYSIS AND EFFICIENCY OPTIMIZATION OF COPPER INDIUM GALLIUM SELENIDE (CIGS) SOLAR CELL

A comparative investigation of the cell performance of Copper Indium Gallium Selenide (CIGS) thin-film solar cell, fabricated using ZnO:Al/i-ZnO/CdS/CIGS layers, has been reported. ADEPT 2.0, a 1D simulation software, were used throughout the whole research for the simulation of light J-V characteristics for different designs. Energy conversion efficiency for each design was calculated from its corresponding light J-V characteristics curve. The efficiency variation were investigated under 1 sun, AM1.5G illumination and optimized layer parameters (thickness) for each layer of the device. The device has designed with an ntype ZnO window layer, an n-type CdS as buffer layer and a p-type CIGS as absorber layer. Molybdenum (Mo) substrate is used for the structure. A totalarea efficiency of 19·75% for ZnO:Al/i-ZnO/CdS/CIGS based thin-film solar cells had been found. Performance is improved due to higher fill factor. The device parameters are optimized separately for each layer. Based on these optimizations, the ultra-thin film solar cell design is proposed after careful consideration of lattice mismatch between two adjacent layers of the device

Studies on the synthesis, characterization, binding with DNA and activities of two cis-planaramineplatinum(II) complexes of the form: cis-PtL(NH(3))Cl(2 )where L = 3-hydroxypyridine and 2,3-diaminopyridine

BACKGROUND: Cis-planaramineplatinum(II) complexes like their trans isomers are often found to be active against cancer cell lines. The present study deals with the synthesis, characterization and determination of activity of new cis-planaramineplatinum(II) complexes. RESULTS: Two cis-planaramineplatinum(II) complexes: cis-(3-hydroxypyridine)(ammine)dichloroplatinum(II) (code named AH3) and cis-(2,3-diaminopyridine)(ammine)dichloroplatinum(II) (code named AH7) have been prepared and characterised based on elemental analyses, IR, Raman, mass and 1H NMR spectral measurements. The interactions of the compounds with pBR322 plasmid DNA have been investigated and their activity against ovarian cancer cell lines: A2780, A2780(cisR )and A2780(ZD047R)have been determined. Like cisplatin, AH3 and AH7 are believed to form mainly monofunctional N7(G) and bifunctional intrastrand N7(G)N7(G) adducts with DNA, causing a local distortion of a DNA strand. As a result, gel mobility of the DNA changes. Both AH3 and AH7 are found to be less active than cisplatin against the three cell lines with AH3 being the more active compound of the two. The higher activity of AH3 is in line with its lower molar conductivity value corresponding to a lower degree of dissociation. CONCLUSION: The differences in activity of AH3, AH7 and cisplatin against the cell lines illustrate structure-activity relationship

Quantitative and morphological characteristics of the human corneal endothelium in relation to age, gender, and ethnicity in cataract populations of South Asia

Purpose: To describe the differences of corneal endothelial cell densities, cell size variability and cell hexagonality in cataract populations of south Asia between sexes and ethnic groups. Methods: 1,235 eyes of 1,235 male and female patients 40-75 years of age with senile cataract were examined with non contact specular microscopy with semi-automated analysis technique. The cell data of the study population was analyzed in relation to age, sex, and ethnic groups. Mean arithmetic differences and the coefficient of variation of repeated observations were calculated to estimate precision of the technique utilized. The main outcome measures were corneal endothelial cell density, cell size variability and cell hexagonality. Results: The mean corneal endothelial cell density was 2,720 cells/mm2, mean cell size variability was 37.8% and percent cell hexagonality 40%. We found statistical significant difference between the three ethnic populations in all the corneal endothelial cell measurements (p &lt; 0.0001). Females had a 2.9% greater cell density than males (p = 0.0001). There was no significant difference in mean cell density according to age. Variability of cell size, however, increased with age (p &lt; 0.001). These findings were consistent across the three ethnic groups. Conclusions: In a total sample of 1,235 eyes distributed evenly in three cataract patient populations of south Asia, we found statistically significant differences of corneal endothelial cell densities of cell size variability and cell hexagonality between sexes and ethnic groups

Effect of Source Activity and Source Volume on Intrinsic Uniformity of SPECT Gamma Camera

Purpose: The quality control of the gamma camera is obligatory for the proper diagnosis of the patients. The most intensive and sensitive routine quality control of gamma camera is intrinsic uniformity. The main objective of this research work is to determine the best parameters for daily quality control testing of intrinsic uniformity for dual head Single Photon Emission Computed Tomography (SPECT) gamma camera.Method: The integral and differential intrinsic uniformity test for both Useful Field Of View (UFOV) and Central Field Of View (CFOV) was done by placing a point source of 99mTc in front of the detectors with removed collimators to measure the effect of source activity and source volume on intrinsic uniformity.Result: The result shows that the best intrinsic uniformity image is obtained at activity volume in the range of 0.2 – 0.7 ml in 3 ml syringe with source activity between 70 – 200 MBq since place of point source on the central axis of the detector at a distance from its face equal to five times the diameter of the useful field of view as defined by the lead mask.Conclusion: Finally we can conclude that, the lower the intrinsic uniformity the better the imaging and diagnosis