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A novel series of zinc(II) complexes of type [ZnL(H2O)2], has been synthesized by the reaction of zinc(II) acetate dihydrate with Schiff bases (H2L) derived from bis-(2-hydrazino-1,3,4-thiadiazole-5- yl)arene/alkanes and 2-hydroxynaphthaldehyde/3,5-dichlorosalicyldehyde in presence of a base. The structures of all the zinc complexes were proposed by elemental analysis and spectroscopic data (IR, 1H, 13C NMR). TGA investigations were carried out to confirm the presence of coordinated water molecules in the zinc complexes. The powder crystal structure of one particular zinc complex has been analyzed by XRD diffraction method and SEM studies have been carried out to investigate the surface morphology. The biological studies reveal that the synthesized zinc complexes possess good antimicrobial properties against different species of pathogenic fungi and bacteria.

Europium(III) and Terbium(III) complexes of type [Eu(L)Cl(H2O)2] and [Tb(L)OAc(H2O)2] (H2L = thiosemicarbazone ligands derived from substituted thiosemicarbazide and benzil/diacetyl) were synthesized. The ligands and synthesized complexes were characterized on the basis of elemental analysis, FT-IR and 1H NMR and X-ray diffraction studies. Photo-physical properties such as excitation spectra, emission spectra and luminescence curves of complexes were investigated. The most intense peak of Eu3+ ion found at 618 nm attributed to 5D0 → 7F2 transition and peak of Tb3+ ion at 549 nm attributed to 5D4 →7F5 transition.

A series of some mononuclear oxovanadium(IV) complexes have been synthesized by the reactions of oxovanadium(IV) sulfatewith Schiff base ligands derived from 3-(phenyl / substituted phenyl)-4-amino-5-mercapto-1, 2, 4-triazoles of aromatic carboxylic acids and benzyl.The complexes were analyzed by different spectroscopic methods (FTIR, UV-Vis., EPR), X-ray diffraction (XRD) analysis, elemental analysis, conductivity measurement, and cyclic voltammetry (CV) analysis. The non-electrolytic nature of the complexes was determined on the basis of the molar conductance values. The powder X-ray diffraction pattern has also been used to determine crystal size and type. On the basis of the physicochemical data, the tentative square- pyramidal geometry of the complexes has been proposed. In vitro antibacterial andantidiabeticproperties by alpha amylase inhibition activities of the selected complexes have also been determined. &nbsp

Europium (III) and Terbium (III) complexes of types [Eu(L)Cl(H2O)3] and [Tb(L)OAc(H2O)3] (H2L = Schiff base derived from condensation of 3-(phenyl/substituted phenyl)-4-amino-5-mercapto-1,2,4-triazole with benzil/diacetyl) have been synthesized by the reactions of anhydrous europium (III) chloride and anhydrous terbium (III) acetate with Schiff bases in ethanol. The synthesized complexes were characterized on the basis of elemental analysis, spectroscopic measurement, magnetic moment, electrical conductance and X-ray diffraction studies. The photoluminescence properties of europium (III) and terbium (III) complexes have also been studied. Europium (III) and Terbium (III) complexes show very strong characteristic emission in red and green regions, respectively.

Fossil records of the now-extinct short-lived nuclide 26Al were analyzed in twelve chondrules from four unequilibrated ordinary chondrites (UOCs), Semarkona (3.0), Bishunpur and Y-791324 (both 3.1) and ALHA76004 (3.3), belonging to the LL group to infer their time of formation. The present data along with those reported by us previously firmly establish a short duration of less than a million years for the major episode of UOC chondrule formation. Nebular processes responsible for chondrule formation started ~ 1 Ma after formation of CAIs and effectively stopped within another one and a half million years in the inner region of the asteroidal belt. Modeling of thermal evolution of chondritic parent bodies suggest that the longer duration of UOC chondrule formation inferred in some of the earlier studies could be attributed to thermal metamorphism experienced by some chondrules in UOC parent bodies. The duration of formation of UOC chondrules is significantly shorter than that for carbonaceous chondrite chondrules.

This study develops a semiautomated methodology for estimating cumulus cloud base heights using high-spatial-resolution Landsat multispectral scanner data. The approach employs a variety of image processing techniques to match cloud edges with their corresponding shadow edges. Cloud base height is then estimated by computing the separation between the corresponding generalized Hough transform reference points. Sixteen subregions, each 30 km*30 km in size, are selected for four Landsat scenes. Standard deviations of cloud base height within each of the subregion range from about 100 m to 150 m. Differences between cloud base heights computed using the Hough transform and a manual verification technique are small. It is estimated that cloud base height accuracies of 50-70 m may be possible using HIRIS and ASTER instruments in the Earth Observation Satellite (EOS) Global Climate Change program. >

Bis(cyclopentadienyl)titanium(IV)/zirconium(IV) complexes, [Cp 2 M(J-R)] [where M = Ti or Zr and H 2 J-R is a Jager type ligand with bridging group R (ethylene, o -phenylene or 4-methyl- o -phenylene], have been synthesized. The subsequent condensations of the complexes (R = o -phenylene) with o -phenylenediamine have also been studied, which cause ring closure and the formation of cyclic complexes. All these derivatives were characterized by elemental analyses, electrical conductance, magnetic moment and spectral (electronic, IR, 1 H NMR) data. 1 H NMR spectra of these complexes indicate that there is rapid rotation of the cyclopentadienyl ring about the metal ring axis. The probable structures of the complexes are proposed.

The problem of robust automatic road detection in remotely sensed images is complicated by the fact that the sensor, spatial resolution, acquisition conditions, road width, road orientation and road material composition can all vary. A novel technique for detecting road pixels in multisource remotely sensed images based on the phase (i.e., orientation or directional) information in edge pixels is described. A very dense map of edges extracted from the image is separated into channels, each containing edge pixels whose phases lie within a different range of orientations. The edge map associated with each channel is de-cluttered. A map of road pixels is formed by re-combining the de-cluttered channels into a composite edge image which is itself then separately de-cluttered. Road detection results are provided for DigitalGlobe and TeiraServerUSA images. Road representations suitable for various applications are then discussed

A new approach to fusion of information from multispectral (MS) imagery is presented. This approach is motivated by the desire to develop an unsupervised classifier which can robustly detect settled regions (i.e., regions containing man-made structures). It is well known in the remote sensing community that the ground truth used in supervised classification are not only difficult to obtain but tend to be inconsistent and difficult to validate. In this paper, we present an unsupervised approach for the problem which combines a two-step analysis of MS imagery with a spatial analysis of higher resolution panchromatic imagery. The MS analysis first combines the multispectral pixel information to create an image of pixel labels generated by the K-Means clustering algorithm. Tile-based features are then computed based on the first and second order class label statistics. These tile features are then used to classify the tiles via a second application of the K-Means clustering algorithm. The results from this MS analysis define clusters of tiles of variable texture that are highly likely to contain evidence of human settlements. Spatial information is then brought to bear by analyzing coregistered high-resolution panchromatic images. By standard detectors we find the corner and edge densities in each coregistered tile. Determination of the threshold values used to determine the presence or absence of human settlements is currently performed by a human observer. The results of this spatial analysis are then compared and combined with the MS results to finally determine the set of tiles containing signs of human settlements.

This document provides the findings from a peer review of the Oak Ridge National Laboratory (ORNL) Hightower 2000 study, which set forth a strategy for characterization of low levels of radioactive contaminants in depleted uranium hexafluoride (DUF{sub 6}) cylinders at the Oak Ridge, Paducah, and Portsmouth gaseous diffusion plants. The information from that study will be used in a DOE-issued request for proposal (RFP) for conversion services from the private sector, to assist vendors in reducing costs associated with contingencies relating to handling this DUF{sub 6} with elevated transuranics (TRUs) and technetium (Tc). The Hightower study developed a general strategy for DUF{sub 6} sampling and analysis in accordance with their task but also recommended the following courses of action: (a) Collect and analyze liquid samples from the two identified Paducah Gaseous Diffusion Plant (PGDP) feed cylinders, feed the DUF{sub 6} into the cascades, and conduct an analysis on the resulting heels by washing and analyzing the wash rinsate; (b) Characterize the cylinder coatings to determine the extent and levels of polychlorinated biphenyl (PCB) contamination; and (c) Verify the characterization of the cylinder inventory's compliance with Department of Transportation (DOT) regulations and the American Society of Mechanical Engineers (ASME) pressure vessel code In addition to the above recommendations, the study also concluded that additional characterization is not likely to result in lower bids by prospective vendors, and that direct sampling of many older tails cylinders may be impractical.

The present investigation was undertaken to assess the binding characteristics of eight different lectins to normal oral mucosa (11 cases), leukoplakia with varying degrees of dysplasia (five cases), and oral mucosal squamous cell carcinoma (12 cases) by the use of biotinylated lectins and avidin biotin peroxidase complexes. The lectins employed were soybean (SBA), peanut (PNA), Dolichos biflorus (DBA), concanavalin A (Con A), wheat germ (WGA), Ulex europaeus (UEA), Ricinus communis (RCA), and Lotus tetragonolobus (LTA). It was observed that SBA, DBA, WGA, UEA, RCA, and LTA showed very strong to strong binding in healthy oral mucosa but no or very weak binding in squamous cell carcinoma. On the contrary, PNA showed weak binding to normal mucosal epithelial cells but showed strong binding to malignant cells. The dysplastic mucosa had an intermediate binding pattern. The lectin Con A was not bound at all or seen in very low concentration in the malignant cells and dysplastic epithelium, but it showed weak binding in the normal mucosa. Hence, we conclude that lectins may be utilized as probes to determine the dysplastic and malignant status of the oral mucosal epithelium.

Variables describing atmospheric circulation and other climate parameters derived from various GCMs and obtained from observations can be represented on a spatio-temporal grid (lattice) structure. The primary objective of this paper is to explore existing as well as some new statistical methods to analyze such data structures for the purpose of model diagnostics and intercomparison from a statistical perspective. Among the several statistical methods considered here, a new method based on common principal components appears most promising for the purpose of intercomparison of spatio-temporal data structures arising in the task of model/model and model/data intercomparison. A complete strategy for such an intercomparison is outlined. The strategy includes two steps. First, the commonality of spatial structures in two (or more) fields is captured in the common principal vectors. Second, the corresponding principal components obtained as time series are then compared on the basis of similarities in their temporal evolution.

The present investigation was undertaken to assess the binding characteristics of eight different lectins on normal mucosa (11 cases), Leukoplakia (5 cases) and squamous cell carcinoma (12 cases) by the use of biotinylated lectins and avidin biotin peroxidase complex. The lectins employed were soybean (SBA), peanut (PNA) Dolichos biflorus (DBA) Concanavalin A (CON A), Wheat germ (WGA), ulex Europeus(UEA), Ricinus communic (RCA) and Lotus tetragonolobus (LTA). It was noticed that SBA, DBA, WGA, UEA, RCA and LTA showed intense to high binding in normal oral mucosa but absent or very weak binding in squamous cell carcinoma. PNA on the contrary had a weak binding to normal mucosal epithelial cells but strong binding to malignant cells. The Leukoplakic mucosa had an intermediate binding pattern. The Lectin CON A was not bound at all or seen in very low concentration in the malignant cells and leukoplakic epithelium but showed weak bindng in the normal mucosa. Hence it appears that Lectin binding studies may provide information about functional differences between cells as the result of normal maturation or pathological changes.

Titanium(IV) alkyl xanthates of the types CpTi(S 2 COR)Cl 2 , CpTi(S 2 COR) 2 Cl and CpTi(S 2 COR) 3 , where R = CH 3 , C 2 H 5 , C 3 H 7 , C 4 H 9 and C 5 H 11 , have been prepared by the reaction of monocyclopentadienyl titanium(IV) trichloride with potassium alkyl xanthates in anhydrous dichloromethane. Conductance and infrared studies suggest that these complexes are non-electrolytes in which all of the xanthate ligands are bidentate. Proton nmr spectra of these complexes indicate that there is rapid rotation of the cyclopentadienyl ring about the metal-ring axis and for the CpTi(S 2 COR) 3 complexes non-equivalence of the alkylxanthate ligands was observed.

A retrospective analysis for a 10-year period (1976-1985) of Road Traffic Accident (RTA) fatalities was carried out in Port Moresby, the capital of Papua New Guinea. The majority of the victims were males and under the age of 45. Passengers formed the largest number, followed by pedestrians and drivers. Most fatal accidents occurred during the weekend. Analysis of injuries reveal head injury to be the dominant and possible cause of death in all three categories of victims. Multiple injuries involving many organs were more common in pedestrians and passengers than drivers. Factors contributing to the high rate of RTAs are discussed and measures to minimise the rate of such accidents have been suggested.

The reactions of mono(cyclopentadienyl)titanium(IV) trichloride with three important series of heterocyclic thiones, viz., triazoline thiones (3-trifluoromethyl-4-amino-1,2,4-triazoline-5-thione (HAFT), 3-trifluoromethyl-4-benzylidene-1,2,4-triazoline-5-thione (HFBT), 3-trifluoromethyl-4-furylidene-1,2,4-triazoline-5-thione (HFFT) and 3-trifluoromethyl-4-salicylidene-1,2,4-traizoline-5-thione (H 2 FST)), quinazolone thiones (3-methyl-quinazol-4-one-2-thione (MQztH), 3-phenyl-quinazol-4-one-2-thione (PQztH) and 3-tolyl-quinazol-4-one-2-thione (TQztH)) and oxadiazole thiones (5-phenyl-1,3,4-oxadiazole-2-thione (BOxtH), 5-nitrophenyl-1,3,4-oxadiazole-2-thione (POxtH) and 5-o-chlorophenyl-1,3,4-oxadiazole-2-thione(COxtH), were studied in anhydrous dichloromethane. The reaction products were characterized on the basis of elemental analyses, electrical conductance, magnetic susceptibility and spectral (electronic, infrared and 1 H NMR) data. Proton NMR spectra indicate that there is rapid rotation of the cyclopentadienyl ring around the metal ring axis on the NMR time scale at 28°C.

Titanium(IV) dithiocarbamato complexes of the typesCpTi(S2CNHR)Cl2 andCpTi(S2CNHR)2Cl, whereR=C8H5N2S, C9H5N2SCl2 and C9H7N2S, have been prepared by the reaction of monocyclopentadienyl titanium(IV) trichloride with the potassium salt of the appropriate dithiocarbamic acid in anhydrous dichloromethane. Conductance and infrared studies indicate that these complexes are non-electrolytes in which all dithiocarbamate ligands are bidentate. Therefore, 5 and 6 coordinate structures can be assigned toCpTi(S2CNHR)Cl2 andCpTi(S2CNHR)2Cl complexes, respectively.1H-NMR spectra indicate that there is rapid rotation of the cyclopentadienyl ring about the metal ring axis.

Praseodymium(III) macrocyclic complexes of types [Pr(L)(H2O)2]Cl3, [Pr(mac1)]Cl3 and [Pr(mac2)(H2O)2]Cl3 (L = ligands derived by the condensation of diacetyl or benzil with semicarbazide or thiosemicarbazide; mac1 = macrocyclic ligands derived by the condensation of diacetyl or benzil with carbohydrazide; mac2 = macrocyclic ligands derived by the condensation of diacetyl or benzil with semicarbazide, thiosemicarbazide or thiocarbohydrazide) have been prepared and characterized by conductance magnetic moment, spectral data, thermal and elemental analyses.

The design of a new low cost analog-to-digital converter system is described. It is based upon the method of linearising the charging process of a storage condenser and is controlled by logic gates. Its tested characteristics have been found to be reliable for application in cosmic ray air shower experiments.

By introducing a correction for surface conductance an attempt has been made to determine the true ζ-potential of fine particles of quartz, Jena and Pyrex glass by the electro-osmotic method in the presence of dilute solutions of NaCl and KCl. The values of ζ-potential, (corrected for surface conductance effect) found for quartz are 87 mV and 76.8 mV at 2.10 and 6.10 −4 N NaCl, respectively. For Jena glass the values obtained are 125.0 mV, 117.7 mV and 111.0 mV at 5.10 −5 , 1.10 −4 and 2.10 −4 N NaCl, respectively, and for Pyrex glass 125.0 mV, 117.0 mV and 111.5 mV at the same concentrations of KCl. Our values are in good agreement with those obtained by previous workers after applying a correction for surface conductance.

Nimbin, the crystalline principle of M. azadirachta Linn. is assigned the molecular formula C29H36O9. 1,2,5-Trimethylnaphthalene was isolated from the dehydrogenation of a reduction product of nimbin. The products of alkaline degradation and pyrolytic experiments establish that nimbin possesses either of the partial structures X or XI.

A rare case of Kaposi's Sarcoma primarily originating in the oral cavity of a 2-year-old male child with subsequent metastatic spread to the lymph node is presented and the literature reviewed.

The effect of temperature on the rate of coagulation of positively charged thorium oxide and ceric oxide hydrosols in presence of KCl and KBr has been studied. An equation relating the time of coagulation and temperature based on the theory of stability of colloids has barn derived and the results have been interpreted quantitativelyin that framework. It has been shown that the maximum value of the potential energy barrier for the coagulation of colloids can be calculated approximately by the use of this method.

This is a case report of a 3-week-old baby with acute intestinal obstruction due to gastric heterotopia protruding like a cyst in the wall of the jejunum.

γ-Sitosterol and the triterpene acids, oleanolic acid and ursolic acid, have been shown to be present in the Indian medicinal plant Oldenlandia corymbosa Linn. Evidence is presented to show that the plant does not contain any alkaloid.