bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of positive end-expiratory pressure and tidal volume on lung injury induced by alveolar instability
Authors: Halter Jeffrey M , Steinberg Jay M , Gatto Louis A , DiRocco Joseph D , Pavone Lucio A , Schiller Henry J , Albert Scott , Lee Hsi-Ming , Carney David , Nieman Gary F
Published: February 2007

Introduction

One potential mechanism of ventilator-induced lung injury (VILI) is due to shear stresses associated with alveolar instability (recruitment/derecruitment). It has been postulated that the optimal combination of tidal volume (Vt) and positive end-expiratory pressure (PEEP) stabilizes alveoli, thus diminishing recruitment/derecruitment and reducing VILI. In this study we directly visualized the effect of Vt and PEEP on alveolar mechanics and correlated alveolar stability with lung injury.

Methods

In vivo microscopy was utilized in a surfactant deactivation porcine ARDS model to observe the effects of Vt and PEEP on alveolar mechanics. In phase I (n = 3), nine combinations of Vt and PEEP were evaluated to determine which combination resulted in the most and least alveolar instability. In phase II (n = 6), data from phase I were utilized to separate animals into two groups based on the combination of Vt and PEEP that caused the most alveolar stability (high Vt [15 cc/kg] plus low PEEP [5 cmH2O]) and least alveolar stability (low Vt [6 cc/kg] and plus PEEP [20 cmH2O]). The animals were ventilated for three hours following lung injury, with in vivo alveolar stability measured and VILI assessed by lung function, blood gases, morphometrically, and by changes in inflammatory mediators.

Results

High Vt/low PEEP resulted in the most alveolar instability and lung injury, as indicated by lung function and morphometric analysis of lung tissue. Low Vt/high PEEP stabilized alveoli, improved oxygenation, and reduced lung injury. There were no significant differences between groups in plasma or bronchoalveolar lavage cytokines or proteases.

Conclusion

A ventilatory strategy employing high Vt and low PEEP causes alveolar instability, and to our knowledge this is the first study to confirm this finding by direct visualization. These studies demonstrate that low Vt and high PEEP work synergistically to stabilize alveoli, although increased PEEP is more effective at stabilizing alveoli than reduced Vt. In this animal model of ARDS, alveolar instability results in lung injury (VILI) with minimal changes in plasma and bronchoalveolar lavage cytokines and proteases. This suggests that the mechanism of lung injury in the high Vt/low PEEP group was mechanical, not inflammatory in nature.
BMP4 and PTHrP interact to stimulate ductal outgrowth during embryonic mammary development and to inhibit hair follicle induction
Authors: Hens Julie R. , Dann Pamela , Zhang Jian-Ping , Harris Stephen , Robinson Gertraud W. , Wysolmerski John
Published: February 2007

The mammary glands develop initially as buds arising from the ventral embryonic epidermis. Recent work has shed light on signaling pathways leading to the patterning and formation of the mammary placodes and buds in mouse embryos. Relatively little is known of the signaling pathways that initiate branching morphogenesis and the formation of the ducts from the embryonic buds. Previous studies have shown that parathyroid hormone-related protein(PTHrP; also known as parathyroid hormone-like peptide, Pthlh) is produced by mammary epithelial cells and acts on surrounding mesenchymal cells to promote their differentiation into a mammary-specific dense mesenchyme. As a result of PTHrP signaling, the mammary mesenchyme supports mammary epithelial cell fate,initiates ductal development and patterns the overlying nipple sheath. In this report, we demonstrate that PTHrP acts, in part, by sensitizing mesenchymal cells to BMP signaling. PTHrP upregulates BMP receptor 1A expression in the mammary mesenchyme, enabling it to respond to BMP4, which is expressed within mesenchymal cells underlying the ventral epidermis during mammary bud formation. We demonstrate that BMP signaling is important for outgrowth of normal mammary buds and that BMP4 can rescue outgrowth of PTHrP-/-mammary buds. In addition, the combination of PTHrP and BMP signaling is responsible for upregulating Msx2 gene expression within the mammary mesenchyme, and disruption of the Msx2 gene rescues the induction of hair follicles on the ventral surface of mice overexpressing PTHrP in keratinocytes (K14-PTHrP). Our data suggest that PTHrP signaling sensitizes the mammary mesenchyme to the actions of BMP4, triggering outgrowth of the mammary buds and inducing MSX2 expression, which, in turn, leads to lateral inhibition of hair follicle formation within the developing nipple sheath.
Hippocampus-like corticoneurogenesis induced by two isoforms of the BTB-zinc finger geneZbtb20in mice
Authors: Nielsen Jakob V. , Nielsen Flemming H. , Ismail Rola , Noraberg Jens , Jensen Niels A.
Published: February 2007

Hippocampus-associated genes that orchestrate the formation of the compact stratum pyramidale are largely unknown. The BTB (broad complex, tramtrack,bric-a-brac)-zinc finger gene Zbtb20 (also known as HOF, Znf288,Zfp288) encodes two protein isoforms, designated Zbtb20S and Zbtb20L, which are expressed in newborn pyramidal neurons of the presumptive hippocampus in mice. Here, we have generated transgenic mice with ectopic expression of Zbtb20S and Zbtb20L in immature pyramidal neurons differentiated from multipotent non-hippocampal precursors. The subiculum and posterior retrosplenial areas in these mice were transformed into a three-layered hippocampus-like cortex with a compact homogenous pyramidal cell layer. Severe malformations of lamination occur in neocortical areas, which coincide with a deficiency in expression of cortical lamination markers. The alterations in cortical cytoarchitecture result in behavioral abnormalities suggestive of a deficient processing of visual and spatial memory cues in the cerebral cortex of adult Zbtb20 transgenic mice. Overall,our in vivo data suggest that Zbtb20 functions as a molecular switch for a pathway that induces invariant pyramidal neuron morphogenesis and suppression of cell fate transitions in newborn neurons.
Three-dimensional finite element prediction of transient thermal history and residual deformation due to line heating
Authors: Biswas P , Mandal N R , Sha O P
Published: February 2007

The parameters of the line heating process have significant effect on thermal history and the resulting residual deformation of the heated plate. The thermal transients are dependent on torch speed, torch height, gas pressure, and nozzle size, which in turn controls the residual deformation of the plate. In the present work, three-dimensional transient finite element thermomechanical analysis of line heating using oxyacetylene gas flame is presented. The analysis is carried out using temperature-dependent material properties, Newton's convection, and Gaussian distribution of heat. To reduce the computation time, a fine mesh was used along and near the heating line that was coarsened at the edges and away from the heating line. Numerical thermal transients and residual deformation were presented for various torch speeds, heat inputs, and different thicknesses of plate (6 mm, 8 mm, 10 mm, and 12 mm thick plates). The results compared fairly well with experimental and previously published results. The reduction in peak temperature, for similar heating conditions, and the increase in structural stiffness of thicker plates resulted in a reduction in out-of-plane deformation. In this work, the computational model for correlation of deformation pattern with heat input for a single heating line has been achieved. This model will further be extended to predict deformation patterns due to multiple parallel and oblique heating lines.
A Novel Route to Prepare ZnO Nanotubes by Using Microwave Irradiation Method
Authors: Kong Xiang-rong , Duan Yueqin , Peng Peng , Qiu Chen , Wu Liyan , Liu Lin , Zheng Wenjun
Published: February 2007

Well-crystallized zinc oxide nanoscale tubular structures have been prepared by using the microwave irradiation method which does not need any templates, seeds, and surfactants. The ZnO nanotubes have regular polyhedral shapes, hollow cores with diameters of 100–200 nm, lengths of 1–3 μm and wall thicknesses of 10–40 nm.
Formation of Mesoporous Silica from a Layered Polysilicate Makatite
Authors: Tamura Hiroaki , Mochizuki Dai , Kimura Tatsuo , Kuroda Kazuyuki
Published: February 2007

Mesoporous silicas with highly ordered and less ordered mesopores were formed through the reaction of a crystalline layered polysilicate makatite with hexadecyltrimethylammonium (C16TMA) chloride. The uniqueness of makatite as a starting material for the formation of mesostructured silica is verified.
Stochastic Approximations and Differential Inclusions, Part II: Applications
Authors: Benaïm Michel , Hofbauer Josef , Sorin Sylvain
Published: February 2007

We apply the theoretical results on “stochastic approximations and differential inclusions” developed in Benaïm et al. [M. Benaïm, J. Hofbauer, S. Sorin. 2005. Stochastic approximations and differential inclusions. SIAM J. Control Optim. 44 328–348] to several adaptive processes used in game theory, including classical and generalized approachability, no-regret potential procedures (Hart and Mas-Colell [S. Hart, A. Mas-Colell. 2003. Regret-based continuous time dynamics. Games Econom. Behav. 45 375–394]), and smooth fictitious play [D. Fudenberg, D. K. Levine. 1995. Consistency and cautious fictitious play. J. Econom. Dynam. Control 19 1065–1089].
Approximation Algorithms for the Job Interval Selection Problem and Related Scheduling Problems
Authors: Chuzhoy Julia , Ostrovsky Rafail , Rabani Yuval
Published: February 2007

In this paper we consider the job interval selection problem (JISP), a simple scheduling model with a rich history and numerous applications. Special cases of this problem include the so-called real-time scheduling problem (also known as the throughput maximization problem) in single- and multiple-machine environments. In these special cases we have to maximize the number of jobs scheduled between their release date and deadline (preemption is not allowed). Even the single-machine case is NP-hard. The unrelated machines case, as well as other special cases of JISP, are MAX SNP-hard. A simple greedy algorithm gives a two-approximation for JISP. Despite many efforts, this was the best approximation guarantee known, even for throughput maximization on a single machine. In this paper, we break this barrier and show an approximation guarantee of less than 1.582 for arbitrary instances of JISP. For some special cases, we show better results.
Constraint Qualifications and KKT Conditions for Bilevel Programming Problems
Authors: Ye Jane J.
Published: February 2007

In this paper we consider the bilevel programming problem (BLPP), which is a sequence of two optimization problems where the constraint region of the upper-level problem is determined implicitly by the solution set to the lower-level problem. We extend well-known constraint qualifications for nonlinear programming problems such as the Abadie constraint qualification, the Kuhn-Tucker constraint qualification, the Zangwill constraint qualification, the Arrow-Hurwicz-Uzawa constraint qualification, and the weak reverse convex constraint qualification to BLPPs and derive a Karash-Kuhn-Tucker (KKT)-type necessary optimality condition under these constraint qualifications without assuming the lower-level problem satisfying the Mangasarian Fromovitz constraint qualification. Relationships among various constraint qualifications are also given.
Synthesis and Physico-Chemical Characterizations of the Lithium-Substituted NASICONS Series with General Formula Li2.8Zr2−y
Si1.8−4y
P1.2+4y
O12 where (0 ≤ y ≤ 0.45)
Authors: Belam W. , Essoumhi A. , Satre P.
Published: February 2007

The lithium-substituted NASICONS materials, with general formula Li2.8Zr2−y
Si1.8−4y
P1.2+4y
O12 where 0 ≤ y ≤ 0.45, were synthesized by the sol–gel method which consisted in calcinig the preliminary precursors at temperatures higher than their crystallization temperatures. The calcined powders have been characterized by physico-chemical techniques: coupled DTA-TGA, XRD and CIS. The coupled DTA-TGA was used to determine the crystallization temperatures and leading to the estimation of the calcined temperatures. The XRD analyses show the obtaining of only the single phase without any detection of other phases as: ZrO2, SiO2, Li2O, ZrSiO4, Li3PO4, Li2SiO3 or Li2ZrO3, according to their JCPDS file cards and suggest that the decrease in the zirconium concentration does not modify the stability of the lithium-substituted NASICONS, whereas the complex impedance spectroscopy results have highlighted the best total electric conductivity for y value equal to 0.225.
Interactions among Three Top-Level Predators in a Polymictic Great Plains Reservoir
Authors: Olson Nathan W. , Guy Christopher S. , Koupal Keith D.
Published: February 2007

After the introduction of hybrid striped bass (white bass Morone chrysops × striped bass M. saxatilis) into Harlan County Reservoir, Nebraska, gill-net catch per unit effort (CPUE) of walleyes Sander vitreus appeared to decline while that of white bass remained stable. This result prompted the question of whether these three species can be managed collectively in reservoir ecosystems. However, despite the frequency with which these three popular sport fishes coexist in Great Plains reservoirs, we are unaware of any studies that evaluate resource overlap among them. Therefore, we compared their diets, diet overlap, isotopic composition, vertical distribution, and vertical overlap in Harlan County Reservoir from June to September 2002 and 2003. All three species consumed similar prey (i.e., gizzard shad Dorosoma cepedianum and Chironomidae), and diet overlap was high (i.e., Pianka's index > 40) during all months. On no occasion did all three predators consume the same sizes of gizzard shad. Hybrid striped bass consumed larger gizzard shad than white bass did in September 2002 and 2003, whereas white bass consumed smaller gizzard shad than walleyes and hybrid striped bass did in August 2002 and 2003. Stable isotope analysis corroborated the diet analysis and indicated that all three species occupied the same trophic level and that each predator derived carbon from a similar prey source. White bass were consistently located within the upper 3 m of water, whereas the vertical distribution of hybrid striped bass and walleyes varied from the surface to 10 m deep. Spatial overlap was therefore not as high as dietary overlap and was variable among species and months. Although diet overlap was high, resource partitioning (i.e., different feeding locations and different sizes of gizzard shad eaten) reduced the negative interactions among the three predators. Therefore, we conclude that concurrent management of these three sport fishes is feasible in highly productive reservoirs similar to the one in this study.
Distinguishing Centrarchid Genera by Use of Lateral Line Scales
Authors: Roberts Nathan M. , Rabeni Charles F. , Stanovick John S.
Published: February 2007

Predator–prey relations involving fishes are often evaluated using scales remaining in gut contents or feces. While several reliable keys help identify North American freshwater fish scales to the family level, none attempt to separate the family Centrarchidae to the genus level. Centrarchidae is of particular concern in the midwestern United States because it contains several popular sport fishes, such as smallmouth bass Micropterus dolomieu, largemouth bass M. salmoides, and rock bass Ambloplites rupestris, as well as less-sought-after species of sunfishes Lepomis spp. and crappies Pomoxis spp. Differentiating sport fish from non-sport fish has important management implications. Morphological characteristics of lateral line scales (n = 1,581) from known centrarchid fishes were analyzed. The variability of measurements within and between genera was examined to select variables that were the most useful in further classifying unknown centrarchid scales. A linear discriminant analysis model was developed using 10 variables. Based on this model, 84.4% of Ambloplites scales, 81.2% of Lepomis scales, and 86.6% of Micropterus scales were classified correctly using a jackknife procedure.
Use of Underwater Visual Distance Sampling for Estimating Habitat-Specific Population Density
Authors: Pink Melissa , Pratt Thomas C. , Fox Michael G.
Published: February 2007

We contrasted fish abundance estimates generated from mark–recapture and underwater visual distance sampling to determine whether the latter method is a potentially valuable fisheries assessment tool. We further examined whether altering the detection function or habitat stratification and including lake characteristics such as Secchi depth, temperature, and fish density affected distance sampling estimates. Distance sampling produced estimates that were comparable to those of mark–recapture techniques (r  2 = 0.60), and the relationship improved considerably when two species that were difficult to sample visually were removed from the analysis (r  2 = 0.88). The precision of mark–recapture estimates was significantly better than that of distance sampling. Distance sampling estimates were more similar to mark–recapture estimates when stratified by habitat than when pooled across habitats. The addition of Secchi depth, temperature, fish density, or a combination thereof to a regression equation that included mark–recapture and distance sampling estimates did not improve the strength of the relation. We were able to detect significant among-habitat differences using habitat-specific density estimates provided from distance sampling. Distance sampling is a less-intrusive means to determine fish abundance and microhabitat patterns and provides a way to determine age-0 fish abundance in addition to information (e.g., school size) that is not readily obtained by mark–recapture studies.
Genetic Analyses Provide Insight into the Early Ocean Stock Distribution and Survival of Juvenile Coho Salmon off the Coasts of Washington and Oregon
Authors: Van Doornik Donald M. , Teel David J. , Kuligowski David R. , Morgan Cheryl A. , Casillas Edmundo
Published: February 2007

Estimating the stock proportions of mixed-stock fishery samples by means of genetic stock identification has played an important role in the management of salmon fisheries. In addition, stock identification of individual fish has applications for population studies, forensic cases, and management issues. We examined 11 microsatellite DNA loci in 84 populations of coho salmon Oncorhynchus kisutch sampled at 78 locations from southern British Columbia to northern California to construct a database of microsatellite allele frequencies. We then evaluated the applicability of the database for estimating stock proportions in a mixed fishery and assigning individuals to their regions of origin. The loci were highly polymorphic: observed heterozygosity ranged from 0.754 to 0.943. Using genetic distance calculations, we identified six major geographic regions and 15 smaller subregions into which the populations grouped. Computer simulations and a sample of 143 coho salmon with known origins showed that the database was sufficient to make accurate stock proportion estimates to the 15 subregions. For the sample of fish with known origins, individual assignments to region of origin were 82.5% accurate for all samples and 97.8% accurate for those where P was greater than 0.95. We used the database to estimate stock proportions and densities of 2,344 coho salmon sampled over eight summers in a juvenile marine ecology study conducted off the coasts of Washington and Oregon. Columbia River juveniles were caught at higher densities than coastal fish throughout the summer. Fish from Columbia River and coastal sources were captured both north and south of their points of sea entry in early summer and at higher densities than in late summer. September catch of Columbia River juveniles was correlated with adult abundance in the following year, indicating that year-class strength for this stock is largely set during the first summer in the ocean.
Symmetry of tetrahydroxycalix[4]arenes
Authors: Gholami A. , Safaei-Ghomi J. , Ashrafi A.R. , Ghorbani M.
Published: February 2007

Graph theory provides an elegant and natural representation of molecular symmetry and the resulting group expressed in terms of permutations is isomorphic to the permutation-inversion group of Longuet-Higgins. In this paper, using the group theory package GAP, the character table and the automorphism group of the Euclidean graph of tetrahydroxycalix[4]arenes were computed. .
The inhibition action of N-furfuryl-N'-phenyl thiourea on the corrosion of mild steel in acid media
Authors: Shetty Divakara , Shetty Prakash , Nayak Sudhaker
Published: February 2007

The inhibiting effect of N-furfuryl-N'-phenyl thiourea (FPTU) on the corrosion of mild steel in aqueous solutions of 0.05 and 0.1MHCl, as well as 0.025 and 0.05 M H2SO4 has been demonstrated using the potentiodynamic polarization technique. The polarization data showed that FPTU acts as an efficient anodic inhibitor for mild steel in both acid solutions. Avery high inhibition efficiency was evidenced in both acid solutions and it was found to vary with the concentration of the inhibitor and temperature. The obtained kinetic parameters of adsorption revealed spontaneous adsorption and a strong interaction of FPTU with the mild steel surface. .
A study of the electrode/solution interface during electrochemical reactions by digital holography
Authors: Chen Shenhao
Published: February 2007

Digital holography was used to study in situ the dynamic changes of the electrode/solution interface and the solution near the electrode during the anodic process of iron in a sulfuric acid solution. The effects of chloride, bromide and iodine ions on this process were also investigated. The magnetic field also has effects on the process. The effects are discussed in combination with SEM results. .
A highly efficient and recoverable bi-cinchona alkaloid ligand for the catalytic asymmetric aminohydroxylation of olefins
Authors: Sun Xiaoli , Wang Qiaofeng , Jiang Ru , Zhang Shengyong
Published: February 2007

A new freely recyclable bi-cinchona alkaloid ligand has been developed for the homogeneous catalytic asymmetric aminohydroxylation (AA) of olefins. It can be easily recovered by precipitation and reused for 5 times without any significant loss in its catalytic efficiency in AA reactions. .
Principal component articial neural network calibration models for the simultaneous spectrophotometric estimation of mefenamic acid and paracetamol in tablets
Authors: Satyanarayana Dondeti , Kannan Kamarajan , Manavalan Rajappan
Published: February 2007

Simultaneous estimation of all drug components in a multicomponent analgesic dosage form with artificial neural networks calibration models using UV spectrophotometry is reported as a simple alternative to using separate models for each component. A novel approach for calibration using a compound spectral dataset derived from three spectra of each component is described. The spectra of mefenamic acid and paracetamol were recorded as several concentrations within their linear range and used to compute a calibration mixture between the wavelengths 220 to 340 nm. Neural networks trained by a Levenberg-Marquardt algorithm were used for building and optimizing the calibration models using MATALAB? Neural Network Toolbox and were compared with the principal component regression model. The calibration models were thoroughly evaluated at several concentration levels using 104 spectra obtained for 52 synthetic binary mixtures prepared using orthogonal designs. The optimized model showed sufficient robustness even when the calibration sets were constructed from a different set of pure spectra of the components. The simultaneous prediction of both components by a single neural network with the suggested calibration approach was successful. The model could accurately estimate the drugs, with satisfactory precision and accuracy, in tablet dosage with no interference from excipients as indicated by the results of a recovery study.
The synthesis and characterization of some ortho-substituted phenoxyalkanoic acids and their derivatives
Authors: Lupea Xenia , Popescu Iuliana , Tarabasanu Corneliu , Ienascu Ioana , Badea Valentin
Published: February 2007

The synthesis of 2-phenoxyalkanoic acids (ethanoic, propanoic, butanoic) was realized by the reaction of ortho-hydroxybenzamide respectively N-phenyl-o-hydroxybenzamide with ?-halogenated acids in aqueous sodium hydroxide solution. 2-[o-(carbamoyl)phenoxy]-2-methyl- and 2-[o-(phenylcarbamoyl)phenoxy]-2-methyl- propanoic acids were obtained by reaction of the appropriate amide with acetone, chloroform and sodium hydroxide. Ethyl esters of 2-phenoxyalkanoic acids were obtained by the reaction of the amide with ethyl esters of ?-halogenated acids in different reaction media. Starting from the ethyl esters of 2-[2-(N-phenylcarbamoyl) phenoxy]alkanoic acids with hydrazine 2-[2-(N-phenylcarbamoyl)phenoxy]alkanoic acids hydrazides were obtained, which are considered key intermediates for the synthesis of several series of new compounds. Schiff bases and N-imido-derivatives were obtained by condensation of hydrazide with substituted aromatic aldehydes respectively maleic anhydride. The synthesized compounds were characterized by physico-chemical methods (FTIR, NMR and mass spectrometry). .
Design of targeted dosage form of ofloxacin+
Authors: Shahar Yar , Siddiqui Ahamed , Ali Ashraf , Manogran E.
Published: February 2007

The targeted pro-drug is a classical pro-drug design often representing a non-specific chemical approach to mask undesirable drug properties, such as limited bioavailability, lack of site specificity, and chemical instability. On the other hand, targeted pro-drug design represents a new strategy for directed and efficient drug delivery. Quinolone antibiotics exert their pharmacological effect by inhibiting the cell wall synthesis of the pathogen. However, development of resistance exists, which instigates for a new higher congener to remain in clinical practice. To overcome this phenomenon and also to produce site-specific activity of the cell walls of the pathogen, ofloxacin is conjugated with a hydroxypropyl methacrylamide polymer backbone moiety. The results of in vitro release studies indicate the possibilities for the development of a new drug for site-specific therapy with an improved t 1/2 of the drug. This novel pro-drugmay have opened a new vista in antibiotic chemotherapy. .
Pyrrolizidine alkaloids from Bulgarian species of the genus Senecio
Authors: Kostova Nadezhda , Christov Veselin , Cholakova Maia , Nikolova Elena , Evstatieva Liuba
Published: February 2007

Nine Bulgarian species from the genus Senecio were studied phytochemically and/or by GC-MS analysis. Senecivernine-N-oxide was isolated and identified by spectral data for the first time. Different types of pyrrolizidine alkaloids were tested for cytotoxicity on murine lymphocytes. At a concentration of 100 ?g/ml, the alkaloid retroisosenine showed immunosuppressive effect. .
Thermogravimetric analysis of the total lipids extracted from the fatty tissue of fallow deer (Cervus Dama dama L)
Authors: Milovanovic Ljiljana , Popovic Ivanka , Skala Dejan , Saicic Snezana
Published: February 2007

Thermogravimetry, TG, of lipids is an appropriate analytical method, commonly used to correlate the kinetic parameters of the thermal degradation of lipids and their composition. Thus, samples of total lipids extracted from the raw fatty tissue of fallow deer were subjected to non-oxidative and oxidative TG analysis. The samples were previously stored for nine months at +4 ?C and -18?C. The material stability was investigated in order to establish the most favorable conditions for the production and storage of different foods. The total lipids were extracted according to the Folch method. The identification and quantitative analysis of the methyl esters of the fatty acids of the total lipids were performed by capillary gas chromatography. Based on the non-oxidative and oxidative TG results, the activation energies of the thermal degradation and oxidation of the total lipids extracted from different samples of fatty tissue were determined. The Doyle-Gorbachev method was used for the calculations. .
Synthesis, characterization and thermogravimetric study of Cu(II) adducts with 3- and 4-amino-1,2,4-triazole, 2-mercaptothiazoline and 2-mercaptopyridine
Authors: Refat Moamen , de Farias
Published: February 2007

The adducts CuCl2?(3amt), CuCl2?2(3amt)?2H2O, CuCl2?3(3amt), CuCl2?(4amt), CuCl2?2(4amt), CuCl2?3(4amt)?2H2O, CuCl2?(2mct)?H2O, CuCl2?2(2mct)?2.5H2O, CuCl2?3(2mct)?2H2O, CuCl2?(2mcp) and CuCl2?2(2mcp)?H2O, where 3-amino-1,2,4-triazole = 3amt, 4-amino-1,2,4-triazole = 4amt, 2-mercaptothiazoline = 2mct and 2-mercaptopyridine = 2mcp, were synthesized by a solid state route and characterized by CHN elemental analysis and infrared spectroscopy. A thermogravimetric study was also performed. It was verified that 4amp is a molecule with a higher ability to act as a bridging ligand in comparison with 3amp. It was also found that, for all compounds, the mono adducts were the most thermally stable ones. Such a fact is in agreement with a higher ionic and covalent character of the metal-ligand bond in surch compounds. .
Coordination diversity of new mononucleating hydrazone in 3d metal complexes: synthesis, characterization and structural studies
Authors: Baligar Rajesh , Revankar Vidyanand
Published: February 2007

The mononucleating hydrazone ligand LH3, a condensation product of salicyloylhydrazine and (2-formylphenoxy)acetic acid, was synthesized and its coordination behavior with first row transition metal(II) ions was investigated by isolating and elucidating the structure of the complexes using elemental analysis, conductivity and magnetic susceptibility measurements, as well as IR, 1H-NMR, electronic and EPR spectral techniques. The ligand forms mononuclear metal(II) complexes of the type [CoLH(H 2O)2], [NiLH(H 2O)2], [CuLH] and [ZnLH]. The ligand field parameters, Dq, B and ? values, in the case of the cobalt and nickel complexes support not only the octahedral geometry around the metal ion, but also imply the covalent nature of the bonding in the complexes. The EPR study revealed the presence of a spin exchange interaction in the solid copper complex and the covalent nature of the bonding. The 1H-NMR study of the zinc(II) complex indicated the non-involvement of the COOH group in the coordination. The physico-chemical study supports for the presence of octahedral geometry around cobalt(II), nickel(II) and tetrahedral geometry around copper(II) and zinc(II) ions. .
Methanol oxidation at platinum electrodes in acid solution: Comparison between model and real catalysts
Authors: Tripkovic A.V. , Gojkovic S.LJ. , Popovic K.Dj. , Lovic J.D.
Published: February 2007

Methanol oxidation in acid solution was studied at platinum single crystals, Pt(hkl), as the model catalyst, and at nanostructural platinum supported on high surface area carbon, Pt/C, as the real catalyst. The linear extrapolation method was used to determine the beginning of hydroxyl anion adsorption. Structural sensitivity of the adsorption was proved and a correlation with the onset of the methanol oxidation current was established at all catalysts. Bisulfate and chloride anions were found to decrease the methanol oxidation rate, but probably did not influence the reaction parth. The specific activity for the reaction increased in the sequence Pt(110) <Pt/C < Pt(111), suggesting that the activity of the supported Pt catalyst can be correlated with the activities of the dominating crystal planes on its surface. .
Studies on a Pb2+ - selective electrode with a macrocyclic liquid membrane: Potentiometric determination of pb2+ ions
Authors: Isvoranu Marian , Luca Constantin , Pleniceanu Maria , Spinu Cezar
Published: February 2007

This paper presents experimental and theoretical data regarding the design, characterization and analytical applications of a non-expensive, liquid-membrane ion-selective electrode for Pb2+ ions. The membrane is a solution of the active complex formed by Pb2+ ions with dibenzo-18-crown-6-ionophore (DB-[18]-C-6) extracted in propylene carbonate (PC). The successful application of the developed electrode for the determination of Pb2+ ions in aqueos solution samples by direct potentiometry and potentiometric titration is presented. For the presented analytical results, there are insignificant systematic errors between the direct potentiometric method with the developed ion-selective electrode and atomic absorption spectrometry. .
Study of the influence of temperature the venting depollution process of soils contaminated with volatile organic compounds
Authors: Brusturean Gabriela-Alina , Carré Jean , Perju Delia , Todinca Teodor
Published: February 2007

Venting is one of the most used in situ remediation methods for unsaturated soils contaminated with volatile organic compounds (VOC). The development of mathematical models and their validation by means of experimental results allowed the identification of the main parameters which influence the soil depollution process. The influence of temperature on the venting depollution process of soils polluted with volatile organic compounds was studied in this investigation. It was found that the depollution efficiency is strongly influenced by the vapour pressure of the pollutants. The conclusions, derived from the performed experimental determinations allowed characterization of the depollution process by using an "equilibrium" model. This model considers the existence of equilibrium between the four pollution phases (vapour, aqueous, "solid" and non-aqueous phase organic liquids) at any moment in time. In order to calculate the vapour pressure, a modified equation of the Antoine model was used in the model. Application of the mathematical model indicates that a 10 ?C temperature rise leads to a two-fold increase in the vapor pressure of a compound. Comparison of the modeled and experimental curves, as well as the values of the obtained performance critterions, verified that the chosen mathematical model describes the influence of temperature on the depollution process very well. .
Basic methodological preconditions for high quality research
Authors: Sevkusic Slavica
Published: February 2007

The paper considers basic methodological preconditions for the qualitative oriented research, in other words, the approaches which in the study of social phenomena rely on theoretical and methodological as well as epistemological premises of a new scientific paradigm. The paper draws special attention to the discussion of criteria of verifiability in qualitative research, which are significantly different from the criteria of positivist approaches. Interpretative research paradigms in social studies have a long history and numerous sources and the very concept of "interpretative shift" consists of a number of different research approaches unified under the name of qualitative methodology. The aim of the paper is not to prove that traditional and new paradigms and quantitative and qualitative research approaches based on them are incompatible in the process of discovering pedagogical reality. The intention is to demonstrate that the complexity of social phenomena requires a complex methodology meaning a complementary use of methods and techniques from both research approaches. The study of qualitative methodological approaches and their application in research, discovery and change of pedagogical reality are particularly important because they may provide new insights into pedagogical reality and a new view of old problems. .
Achievement of Serbian eighth grade students in science
Authors: Antonijevic Radovan
Published: February 2007

The paper considers the main results and some educational implications of the TIMSS 2003 assessment conducted in Serbia in the fields of the science achievement of Serbian eighth grade students and the science curriculum context of their achievement. There were 4264 students in the sample. It was confirmed that Serbian eighth graders had made average scale score of 468 points in the science, and with this achievement they are placed in the zone of the top of low international benchmarking level, very close to the point of intermediate benchmark. The average science achievement of the Serbian eighth graders is somewhat below the general international science achievement. The best results were achieved in the science content domain of "chemistry", and the lower results in the content domain of "environmental science". Across the defined science cognitive domains, it was confirmed that the Serbian students had achieved the best results in cognitive domain of "factual knowledge" and weaker results in "reasoning and analysis". The achieved results raise many questions about contents of the science curriculum in Serbia, its overall quality and basic characteristics of its implementation. These results can be eligibly used to improve the science curricula and teaching in Serbian primary school. .
Quantitative change of meta-cognitive activities of students effected by problem-solving teaching
Authors: Miscevic Gordana
Published: February 2007

Based on Fleivel?s theoretical framework, the subject of this paper is the study of changes in frequency of meta-cognitive activities affected by a two-month implementation of problem solving teaching in the subject of natural studies. The sample was made up of ten-year-old students. The instrument used was adapted to the student age; they were asked to state the frequency of meta-cognitive activities which they believe they applied before, during and after problem solving. The presence of meta-cognitive activities was following up in the phase of planning, monitoring and evaluation. The results show that problem solving teaching contributes to a larger presence of meta-cognitive activities in the process of planning compared to traditional teaching. In order to have a more comprehensive identification of potential meta-cognitive activities subsequent research should be directed at the use of not only this and similar instruments but also "thinking aloud" protocol. .
Young people’s attitudes to multculturalism and acceptance of plurality of ideas
Authors: Djurisic-Bojanovic Mirosava
Published: February 2007

The paper examines the possibility of a more efficient and effective education for a democratic, multicultural society from the perspective of psychological findings concerning personal democratic and antidemocratic predispositions. The starting premise of the research is a that there is a significant connection between the attitude to multiculturalism and acceptance of plurality of ideas. The research aimed to provide an answer to the question whether openness to other cultures is connected with a readiness to accept plurality of ideas. The research was carried out on a suitable sample (N=306) of multicultural groups of grammar school and secondary vocational school students in Subotica in 2005. The results point to a significant positive connection between attitudes to other cultures and acceptance of plurality of ideas (r=.43; p< .01). The school type also affects the degree of acceptance of plurality of ideas. The author concludes that the findings offer support for an integrative approach to education for democracy, while practice in accepting plurality of ideas through different subjects represents a necessary condition for the acceptance of democratic behavior and thinking. This is how the education for democracy can be made more efficient and effective and integration of young people into democratic and multicultural society facilitated. .
Imaging findings and surgical treatment of hemivertebrae in three dogs
Authors: Jeffery Nicholas D. , Smith Peter M. , Talbot Catherine E.
Published: February 2007

Case Description—3 immature screw-tailed dogs were evaluated because of progressive pelvic limb paraparesis.

Clinical Findings—Each dog had marked ataxia and paresis of the pelvic limbs and a palpable deformity of the midthoracic portion of the vertebral column. Pain perception in the pelvic limbs was considered normal, and there was no evidence of fecal or urinary incontinence in any of the 3 dogs. Radiography and magnetic resonance imaging revealed hemivertebrae with severe dorsoventral stenosis of the vertebral canal resulting in spinal cord compression in 2 dogs and lateral compression in the other.

Treatment and Outcome—Each dog underwent decompressive surgery consisting of dorsal laminectomy or hemilaminectomy and vertebral stabilization by use of combinations of Kirschner wires or threaded external fixator pins plus polymethylmethacrylate bone cement. All dogs regained strong locomotor function with minimal residual pelvic limb ataxia.

Clinical Relevance—Little detailed information regarding surgical treatment of hemivertebrae in dogs is available; results of treatment in these 3 dogs suggest that spinal cord decompression and stabilization of the vertebral column can achieve a satisfactory, functional outcome.
Keratoconjunctivitis sicca associated with administration of etodolac in dogs: 211 cases (1992–2002)
Authors: Klauss Gia , Giuliano Elizabeth A. , Moore Cecil P. , Stuhr Charles M. , Martin Stacy L. , Tyler Jeff W. , Fitzgerald Kelsie E. , Crawford Debra A.
Published: February 2007

Objective—To characterize features and response to treatment of keratoconjunctivitis sicca (KCS) associated with oral administration of etodolac in dogs.

Design—Retrospective case series.

Sample Population—65 cases obtained from a survey of veterinary ophthalmologists (group A) and 146 cases reported to Fort Dodge Animal Health (group B).

Procedures—Data analyzed included breed, sex, age, weight, dose and duration of etodolac administration, results of Schirmer tear test at the time of diagnosis and last follow-up, treatments, and response to treatments. Groups A and B were analyzed separately by use of forward stepwise logistic regression models developed to predict probability of complete remission or clinical improvement as a function of several variables.

Results—Most dogs developed severe KCS (84 eyes of 50 dogs [group A]; 111 eyes of 62 dogs [group B]). Resolution of KCS occurred in 7 of 65 (A) and 23 of 146 (B) dogs. No response to treatment was observed in 26 of 65 (A) and 27 of 146 (B) dogs. Fifty-one (A) and 52 (B) dogs had records that were sufficiently complete to use in models. In group B, dogs with etodolac treatment intervals < 6 months prior to the onset of KCS were 4.2 times as likely to have remission as were dogs with treatment intervals ≥ 6 months.

Conclusions and Clinical Relevance—Shorter duration of etodolac administration (< 6 months) was associated with improved outcome in 1 population of dogs. Monitoring of tear production should be considered prior to and during administration of etodolac in dogs.
Bilateral phacoemulsification and intraocular lens implantation in a great horned owl
Authors: Carter Renee T. , Murphy Christopher J. , Stuhr Charles M. , Diehl Kathryn A.
Published: February 2007

Case Description—A great horned owl of estimated age < 1 year that was captured by wildlife rehabilitators was evaluated because of suspected cataracts.

Clinical Findings—Nuclear and incomplete cortical cataracts were evident in both eyes. Ocular ultrasonography revealed no evidence of retinal detachment, and electroretinography revealed normal retinal function.

Treatment and Outcome—For visual rehabilitation, cataract surgery was planned and intraocular lens design was determined on the basis of values obtained from the schematic eye, which is a mathematical model representing a normal eye for a species. Cataract surgery and intraocular lens placement were performed in both eyes. After surgery, refraction was within −0.75 diopters in the right eye and −0.25 diopters in the left eye. Visual rehabilitation was evident on the basis of improved tracking and feeding behavior, and the owl was eventually released into the wild.

Clinical Relevance—In raptors with substantial visual compromise, euthanasia or placement in a teaching facility is a typical outcome because release of such a bird is unacceptable. Successful intraocular lens implantation for visual rehabilitation and successful release into the wild are achievable.
Delineation of the cryptic 1qter deletion phenotype
Authors: Merritt J. Lawrence , Zou Ying , Jalal Syed M. , Michels Virginia V.
Published: February 2007

The 1qter microdeletion is often reported in the literature as a part of a complex chromosome rearrangement. We describe a patient with a normal initial cytogenetic analysis later found by subtelomeric FISH to have a de novo isolated 1qter microdeletion. Further characterization was completed through microarray comparative genomic hybridization (CGH) and specific bacterial artificial chromosomes (BACs) to a region of 5.2–5.3 Mbp. Six additional cases were reviewed from a literature search. While no particular feature is specifically unique, the most frequently associated features include short stature, developmental delay and mental retardation, microcephaly, seizures, abnormal corpus callosum, and abnormal ear shape. This further delineates the phenotype and further narrows the chromosomal region responsible for a 1qter microdeletion phenotype. © 2007 Wiley‐Liss, Inc.
Congenital arhinia: Molecular‐genetic analysis of five patients
Authors: Sato Daisuke , Shimokawa Osamu , Harada Naoki , Olsen Oystein E. , Hou Jia‐Woei , Muhlbauer Wolfgang , Blinkenberg Ellen , Okamoto Nobuhiko , Kinoshita Akira , Matsumoto Naomichi , Kondo Shinji , Kishino Tatsuya , Miwa Nobutomo , Ariga Tadashi , Niikawa Norio , Yoshiura Koh‐ichiro
Published: February 2007

Congenital arhinia, complete absence of the nose, is an extremely rare anomaly with unknown cause. To our knowledge, a total of 36 cases have been reported, but there has been no molecular‐genetic study on this anomaly. We encountered a sporadic case of congenital arhinia associated with a de novo chromosomal translocation, t(3;12)(q13.2;p11.2). This led us to analyze the patient by BAC‐based FISH for translocation breakpoints and whole‐genome array CGH for other possible deletions/duplications in the genome. We found in this patient an approximately 19 Mb deletion spanning from 3q11.2 to 3q13.31 but no disruption of any gene(s) at the other breakpoint, 12p11.2. As the deleted segment at 3q was a strong candidate region containing the putative arhinia gene, we also performed the array CGH in four other arhinia patients with normal karyotypes, as well as mutation analysis of two genes, COL8A1 and CPOX, selected among hundreds of genes located to the deleted region, because they are expressed during early stages of human craniofacial development. However, in the four patients, there were no copy number aberrations in the region examined or no mutations in the two genes. Although our study failed to identify the putative arhinia gene, the data may become a clue to unravel the underlying mechanism of arhinia. © 2007 Wiley‐Liss, Inc.