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Colloidal lithography is a cost-effective and scalable technique for producing nanostructures with defined shapes and sizes. In this study, colloidal lithography was utilized to fabricate nanostructured silver layers for a three-layer transparent conductive oxide AZO/Ag/AZO. The silver nanostructures were deposited onto an aluminum-doped zinc oxide (AZO) substrate via RF sputtering at room temperature and served as the conductive layer in the AZO/Ag/AZO stack. The resulting nanostructured silver layer exhibited a peak of 93% transmittance in the 300–400 nm range and a steady value of 61% in the 400–1000 nm range. The sheet resistance value was 9.3 Ω/sq for the 15 nm Ag film after polystyrene nanospheres (PS) were chemically removed; it showed improved electrical conductivity and transparency compared to traditional AZO layers. Scanning electron microscopy (SEM) images revealed a disordered, random distribution of the PS in the films. The incorporation of the optimized nanostructured silver layer in this structure resulted in highly competent transparent conductive oxide (TCO), whose performance was evaluated using a figure of merit. This work demonstrates the potential of colloidal lithography for the fabrication of nanostructured silver layers in transparent conductive oxides, opening new alternatives for the development of low-cost and highly efficient transparent conductors. [ABSTRACT FROM AUTHOR]

Background: Lactoferrin (LTF) is an iron-binding glycoprotein found in milk and other exocrine secretion with antibacterial activity proposed as an alternative to mastitis treatment or prevention. LTF has been proposed as a candidate gene for mastitis resistance selection. The aim of this paper was to assess LTF promotor to explore variations with potential association to mastitis resistance in dairy cows from Honduras. Methods: A resequencing of promotor and Exon I of LTF gene in extreme mastitis susceptibility cows (126 Holstein and Holstein crossbred) was performed. Results: Eight polymorphisms were found in promotor region, four of them were novel variations. Two were important by frequency among extreme groups, but a polymorphism in − 421 A/T position was significantly (P = 0.0188) associated to mastitis susceptibility. Conclusion: Results support the key role of regulatory region of LTF gene. Some candidate genes are proposed in association with mastitis traits and implications are discussed. [ABSTRACT FROM AUTHOR]

A crossed beam pulsed laser deposition configuration was used to prepare nanocomposites Bi/TiO2 thin films on two different substrates. The multilayered system was formed by depositing TiO2 and Bi layers alternately. In order to embed the Bi nanostructures in TiO2, the subsequent TiO2 layers were synthesized using a constant number of laser pulses (3000) corresponding to a thickness of approximately 21 nm. The Bi nanostructures were deposited on the TiO2 layers alternately by irradiating the Bi target with 30, 100, 200, and 300 laser pulses. In this way, the Bi nanostructures were embedded inside the TiO2 matrix. A total of 8 samples with bismuth and one reference, with TiO2 only, were produced. Transmission Electron Microscopy (TEM) showed that nearly spherical nanoparticles (NPs) were obtained at lower number of pulses, whereas at 300 pulses a quasi-percolated nanostructured Bi film was obtained. X-Ray Photoelectron Spectroscopy (XPS) revealed that the TiO2 layers were not affected due to the bismuth presence. Raman Spectroscopy showed vibrational features characteristic of the rutile phase for the titania layer. The Raman spectrum of the multilayer prepared using 300 laser pulses on the bismuth, suggests that the Bi layer is formed by a mixture of metallic Bi, and α-Bi2O3. The Ultraviolet–Visible Spectroscopy reveals that no substantial changes are presented in the transmittance spectra indicating similar optical properties of the different deposits. Finally, the photoluminescence emission spectra indicate that the substrate position in the deposition chamber affects the electronic structure of the material. [ABSTRACT FROM AUTHOR]

This work presents a methodology based on the WO3/Ag/WO3 (WAW) tri-layer configuration for obtaining indium-free TCOs by RF sputtering at room temperature. The tri-layer performance is shown to be very sensitive to the thickness variations. Through the optimization of the WO3 top layer, it was possible to obtain a combination of thicknesses that allow to maximize the optical transmittance and at the same time lower the sheet resistance, this translates into an excellent compromise between these two properties that are usually antagonists. Using a metallic layer with a thickness that is just at its percolation limit, high electrical conductivity values can be obtained without compromising the optical transmittance. Thickness variation of the dielectric layers in turn, allowed to optimize the transport of the electrons to the metallic film. The overall tri-layer performance was evaluated using multifigure of merit analysis. Our best results were obtained for WO3(40 nm)/Ag(7 nm)/WO3(20 nm) with 1.2 Ω/sq sheet resistance and transmittance above 85%. Therefore, it is possible to obtain a TCO in an indium-free tri-layer WAW configuration at room temperature with good performance that represents a viable alternative that is not restricted by the scarcity of indium. [ABSTRACT FROM AUTHOR]

Surface adsorption of amphiphilic molecules is a vital mechanism of boundary lubrication on stainless steel surfaces. The self-assembly of four fatty acid-based organic friction modifiers in two alkane solvents and their adsorption onto stainless steel surfaces was investigated using Dynamic Light Scattering and Quartz Crystal Balance with Dissipation, respectively. These properties were related to the friction force between a sharp tip and the steel surface measured using Lateral Force Microscopy. The molecular structures of the organic friction modifiers were chosen in order to study the effects of unsaturation and number of alkyl chains as well as the composition of the polar head groups on their assembly in solution, adsorption, and nanotribological behavior. Sorbitan monooleate and dioleate adsorb as monolayers with their alkyl chains either in the upright or tilted configuration, depending on their concentration. If large supramolecular structures were present in the solvent, i.e., for sorbitan monolaurate and glycerol monooleate, micelle adsorption and rearrangement on the surface and multilayer formation took place, respectively. A correlation between the adsorption rate constant and the coefficient of friction of the organic friction modifiers was revealed in these studies, with the coefficient of friction decreasing with an increase in the adsorption rate. [ABSTRACT FROM AUTHOR]

This study is focused on the anaerobic biological treatment of a polyethylene glycol (PEG)-rich industrial wastewater and mechanically sorted organic fraction of municipal solid wastes, called residual organic matter (ROM), in order to assess the effects of mixing these substrates to produce volatile fatty acids (VFA) through anaerobic co-fermentation or biogas through anaerobic co-digestion. As a consequence of the anaerobic co-digestion of PEG and ROM (PEG representing a 3.5% v/v), the specific methane production (SMP) reached 0.44 Nm3 CH4 kg−1 volatile solids (VS) in front of 0.30 Nm3 CH4 kg−1 VS of the anaerobic digestion (AD) control reactor, with just a 35% higher organic loading rate (OLR) on VS basis. The fast degradation of PEG implied that effluent quality was nearly the same of AD process, showing high stability with neither increase of VS nor significant variations in nutrients. Acidogenic fermentation was carried out in batch tests for several mixtures of PEG industrial wastewater and ROM, where the percentages of PEG-rich wastewater on VS basis were 0, 12.5, 25, 37.5 and 50%. The best results of VFA increase per unit of VS of co-substrate fed was obtained for the mixture with 12.5% of PEG wastewater at 5 days retention time. The same mixture was fed in an anaerobic fermenter under mesophilic conditions treating ROM at an HRT of 3.5 days and without modifying the OLR (VS basis). As a consequence of this co-fermentation, the production of VFA was increased by 14% (12.1 g VFA L−1) when compared with the values obtained in mono-fermentation. Moreover, the percentages of acetic acid + propionic acid (66.5%) was in the range than that obtained with mono-fermentation of ROM (64.6%). [ABSTRACT FROM AUTHOR]

CdS buffer layer plays an important role in thin film solar cells; as a result, a deep understanding of its physical properties and impact on solar cell performance is highly required. In this work, we report results on growth conditions of CdS thin films deposited by chemical bath method to be used as insulators in MIS structure instead of the traditionally assumed p-n junction. Three different Cd sources-CdCl, Cd(NO), and CdSO-are considered for CdS processing. The impact of Cd source on CdS physical properties as well as on the electro-optical device properties of CdS/CZTGSe solar cells is evaluated. Furthermore, interface state properties are calculated as a function of temperature. These states are a result of the CdS interaction with both the TCO and Kesterites, depending on the Cd source used in solution of the chemical bath deposition. Besides, some important requirements to be considered in order to improve device efficiency are discussed in the present work. [ABSTRACT FROM AUTHOR]

More than one million hectares have undergone irrigation modernization in Spain during this century. Irrigation modernization to pressurized systems is currently facing challenges derived from increasing electricity prices and decreasing public subsidies. The economic viability of such projects is compromised, and the number of projects is decreasing. Pressurized collective networks are commonly designed and managed using hydraulic simulation tools and probabilistic hypotheses on hydrant use. In this paper, a simulation tool is presented that widens the scope of the analysis by combining hydraulics with agronomy, agrometeorology, solid-set sprinkler irrigation and economics. The CINTEGRAL software simulates the net benefit of the seasonal operation of a collective pressurized irrigation network. The software incorporates an optimization module for the electricity contract associated with the pumping station. CINTEGRAL runs on a time step of a half-hour, and simulates the irrigation season of a variety of crops. The software was applied to analyze the economic benefit of a Water User Association (WUA) under different design and management scenarios (on-demand, network sectoring and dividing the irrigated area in separate networks). In the studied WUA, the network sectoring scenario provided important energy savings (22%) but negatively affected yield by a similar economic magnitude. The division of the area in two independent networks was the most cost-effective scenario. Network topologies, cropping patterns, market prices, irrigation infrastructure, soil conditions and management rules determine the optimum WUA management options. CINTEGRAL is a comprehensive simulation tool designed to help designers and managers guarantee the economic viability of their projects. [ABSTRACT FROM AUTHOR]

Purpose: Morphometry techniques were applied to quantify the normal tissue therapy response in patients receiving whole-brain radiation for intracranial malignancies. Methods: Pre- and Post-irradiation magnetic resonance imaging (MRI) data sets were retrospectively analyzed in N = 15 patients. Volume changes with respect to pre-irradiation were quantitatively measured in the cerebrum and ventricles. Measurements were correlated with the time interval from irradiation. Criteria for inclusion included craniospinal irradiation, pre-irradiation MRI, at least one follow-up MRI, and no disease progression. The brain on each image was segmented to remove the skull and registered to the initial pre-treatment scan. Average volume changes were measured using morphometry analysis of the deformation Jacobian and direct template registration-based segmentation of brain structures. Results: An average cerebral volume atrophy of $$-$$ 0.2 and $$-$$ 3 % was measured for the deformation morphometry and direct segmentation methods, respectively. An average ventricle volume dilation of 21 and 20 % was measured for the deformation morphometry and direct segmentation methods, respectively. Conclusion: The presented study has developed an image processing pipeline for morphometric monitoring of brain tissue volume changes as a response to radiation therapy. Results indicate that quantitative morphometric monitoring is feasible and may provide additional information in assessing response. [ABSTRACT FROM AUTHOR]

Eating disorders (ED) can arise from a combination of biological and psychological factors. Some studies suggest that intellectual factors might be important in the development of ED, although the evidence is still scarce. The aim of this study was to examine the association between cognition measurements (cognitive performance and academic achievement) and the risk of developing ED in adolescents considering their weight status. The sample consisted of 3,307 adolescents (1,756 girls), aged 13-18.5 years, who participated in the AVENA ( n = 1,430; 783 girls) and AFINOS ( n = 1,877; 973 girls) studies. Cognitive performance was measured by the TEA test in the AVENA study, and academic achievement was self-reported in the AFINOS study. ED risk was evaluated in both studies by using the SCOFF questionnaire. Body mass index was calculated to classify adolescents as non-overweight or overweight (including obesity). Overweight adolescents showed a higher risk of developing ED than non-overweight ones in both studies. In the AVENA study, overweight boys with low performance in reasoning ability showed increased risk of ED ( p = 0.05). In the AFINOS study, overweight boys with low academic performance in physical education and non-overweight girls with low academic achievement in all the areas analyzed showed higher risk of ED than their peers (all p < 0.05). Conclusion: No association between cognitive performance and ED risk was found in adolescents, while academic achievement was associated with ED risk, especially in non-overweight girls. The non-cognitive traits that accompany academic achievement could influence the likelihood of developing ED in these girls. [ABSTRACT FROM AUTHOR]

crude biosurfactant mixture was produced in a 1.4 L tubular reactor by a mixed culture; after the thermal treatment of the whole culture an increase in emulsification activity and surface tension was observed, with a main effect on the first one. The emulsification index of the mixture obtained was of 60.4 %. The crude mixed biosurfactant was used to enhance hydrocarbon biodegradation of intemperized soil in a slurry reactor, for which two biodegradation assays were carried out. In the first reactor (R1), the crude mixed biosurfactant was added along with inoculum at initial stage, and the second reactor (R2) was inoculated 5 days after the initial biosurfactant addition. When the crude biosurfactant mixture was added as a pretreatment (R2), the extent and rate of hydrocarbon biodegradation was increased efficiently in the slurry phase reactor 1.3-folds in comparison to non-biosurfactant control. So, the initial hydrocarbon content (9,275 g/kg of dry soil) was reduced to 674 ± 34 mg kg-1 with about 92% of removal efficiency at the 10 days of treatment in the slurry reactor. On the other hand, the bioreactor that received the biosurfactant and the inoculum at the initial stage showed slower hydrocarbon consumption and as result hydrocarbon content was reduced by approximately 34%. [ABSTRACT FROM AUTHOR]

Microrheology measurements were performed on suspensions of bacteriophage fd with diffusive wave spectroscopy in the concentrated regime, at different values of ionic strength. Viscosity vs. shear rate was also measured, and the effect of bacteriophage concentration and salt addition on shear thinning was determined, as well as on the peaks in the viscosity vs. shear curves corresponding to a transition from tumbling to wagging flow. The influence of concentration and salt addition on the mean square displacement of microspheres embedded in the suspensions was determined, as well as on their viscoelastic moduli up to high angular frequencies. Our results were compared with another microrheology technique previously reported where the power spectral density of thermal fluctuations of embedded micron-sized particles was evaluated. Although both results in general agree, the diffusive wave spectroscopy results are much less noisy and can reach larger frequencies. A comparison was made between measured and calculated shear modulus. Calculations were made employing the theory for highly entangled isotropic solutions of semiflexible polymers using a tube model, where various ways of calculating the needed parameters were used. Although some features are captured by the model, it is far from the experimental results mainly at high frequencies. [ABSTRACT FROM AUTHOR]

In the present paper, the ionic conductivity and the dielectric relaxation properties on the poly(vinyl alcohol)-CF3COONH4 polymer system have been investigated by means of impedance spectroscopy measurements over wide ranges of frequencies and temperatures. The electrolyte samples were prepared by solution casting technique. The temperature dependence of the sample’s conductivity was modeled by Arrhenius and Vogel-Tammann-Fulcher (VTF) equations. The highest conductivity of the electrolyte of 3.41×10 − 3 (Ωcm) − 1 was obtained at 423 K. For these polymer system two relaxation processes are revealed in the frequency range and temperature interval of the measurements. One is the glass transition relaxation ( α-relaxation) of the amorphous region at about 353 K and the other is the relaxation associated with the crystalline region at about 423 K. Dielectric relaxation has been studied using the complex electric modulus formalism. It has been observed that the conductivity relaxation in this polymer system is highly non-exponential. From the electric modulus formalism, it is concluded that the electrical relaxation mechanism is independent of temperature for the two relaxation processes, but is dependent on composition. [ABSTRACT FROM AUTHOR]

We report on electrical relaxation measurements of (1 − x)NH4H2PO4- xTiO2 ( x = 0.1) composites by admittance spectroscopy, in the 40-Hz–5-MHz frequency range and at temperatures between 303 and 563 K. Simultaneous thermal and electrical measurements on the composites identify a stable crystalline phase between 373 and 463 K. The real part of the conductivity, σ’, shows a power-law frequency dependence below 523 K, which is well described by Jonscher’s expression $\sigma'=\sigma_0(1+(\omega/\omega_p)^n)$ , where σ 0 is the dc conductivity, ω p /2 π = f p is a characteristic relaxation frequency, and n is a fractional exponent between 0 and 1. Both σ 0 and f p are thermally activated with nearly the same activation energy in the II region, indicating that the dispersive conductivity originates from the migration of protons. However, activation energies decrease from 0.55 to 0.35 eV and n increases toward 1.0, as the concentration of TiO2 nanoparticles increases, thus, enhancing cooperative correlation among moving ions. The highest dc conductivity is obtained for the composite x = 0.05 concentration, with values above room temperature about three orders of magnitude higher than that of crystalline NH4H2PO4 (ADP), reaching values on the order of 0.1 (Ω cm) − 1 above 543 K. [ABSTRACT FROM AUTHOR]

We present a critical assessment of the diffusing wave spectroscopy (DWS) technique for obtaining the characteristic lengths and for measuring the loss and storage moduli of a reasonable well-known wormlike micelle (WM) system. For this purpose, we tracked the Brownian motion of particles using DWS embedded in a Maxwellian fluid constituted by a wormlike micellar solution made of cetyltrimethylam-monium bromide (CTAB), sodium salicylate (NaSal), and water. We found that the motion of particles was governed by the viscosity of the solvent at short times and by the stress relaxation mechanisms of the giant micelles at longer times. From the time evolution of the mean square displacement of particles, we could obtain for the WM solution the cage size where each particle is harmonically bound at short times, the long-time diffusion coefficient, and experimental values for the exponent that accounts for the broad spectrum of relaxation times at the plateau onset time found in the 〈Δ r 2( t)〉 vs. time curves. In addition, from the 〈Δ r 2( t) vs. time curves, we obtained G′( ω) and G″( ω) for the WM solutions. All the DWS microreological information allowed us to estimate the characteristic lengths of the WM network. We compare our DWS microrheological results and characteristic lengths with those obtained with mechanical rheometers at different NaSal/CTAB concentration ratios and temperatures. [ABSTRACT FROM AUTHOR]

Thermally stimulated depolarization currents, TSDC, wide-angle X-ray scattering, WAXS, differential scanning calorimetry, DSC, and polarized light optical microscopy, PLOM, have been used to examine poly(L-lactide)- b -poly( $ \upvarepsilon$ -caprolactone) diblock copolymers in a wide composition range. Both components are crystallizable and the miscibility in the amorphous phase has been determined from the behavior of the primary relaxations which are the dielectric manifestation of the glass transition, and also from the superstructural morphology revealed by PLOM and the compositional dependence of the melting points as determined by DSC. Distinct segmental mobilities in the amorphous phase which can be well resolved by TSDC are present; the $ \upalpha$ mode of the slower component shifts to lower temperatures as the PCL content increases while the glass transition of neat PCL is present for all compositions. A relaxation times bimodal distribution is apparent for PCL-rich copolymers. The composition dependence of the multiple glass transitions detected in these weakly segregated copolymers are predicted by the self-concentration model for a miscible blend made of components with a large Tg contrast. [ABSTRACT FROM AUTHOR]

In gynodioecious populations, the frequency of females is expected to have a strong influence on the contemporary genetic structure of populations. Historical patterns of range contraction and expansion are also known to influence the genetic diversity of plant populations. We explore the influence of male sterility and colonization history on the genetic diversity in populations of Kallstroemia grandiflora along the Pacific of México. Both the overall population Fis and Fis values of hermaphrodites showed a negative association with female frequency. Genetic diversity declined with latitude. Our results provide evidence that females have a significant effect on the genetic structure as predicted by theoretical models and provide support for the hypothesis that historical processes have modified the genetic structure of K. grandiflora.Heredity (2006) 97, 269–274. doi:10.1038/sj.hdy.6800849; published online 31 May 2006 [ABSTRACT FROM AUTHOR]

Cervical cancer constitutes a major health problem in Mexico and other developing countries. The purpose of our study was to assess the experience of a comprehensive national oncological reference center on pelvic exenteration for post-radiotherapy recurrent or persistent cervical cancer, describing the prognostic value of time to recurrence, procedure complications, and survival. Medical records from 42 patients with post-radiotherapy recurrent or persistent cervical cancer who underwent a pelvic exenteration with curative purposes from 1984 to 1989 were retrospectively reviewed. Histological diagnoses were squamous cell carcinoma (32 patients), adenosquamous carcinoma (9 patients), and adenocarcinoma (1 patient). Average follow up was of 56.3 mo after the procedure and global survival at 5 yr was 65.8%. Survival for patients with early recurrence was 56.9% vs 78% for patients with late recurrence (p = 0.05). Complications were observed in 65.3% of the cases with a surgical mortality of 4.8%. Pelvic exenteration is a surgical procedure with high morbidity in spite of the recent medical advances. Pelvic exenteration should not be indicated with palliative purposes owing to the high rate of complications. Patients with tumor persistence or early recurrence have a worse prognosis. In well-selected cases, exenteration may provide a survival benefit. [ABSTRACT FROM AUTHOR]

Augmented Lagrangian algorithms are very popular tools for solving nonlinear programming problems. At each outer iteration of these methods a simpler optimization problem is solved, for which efficient algorithms can be used, especially when the problems arc large. The most famous Augmented Lagrangian algorithm for minimization with inequality constraints is known as Powell-Hestenes-Rockafellar (PHR) method. The main drawback of PHR is that the objective function of the subproblems is not twice continuously differentiable. This is the main motivation for the introduction of many alternative Augmented Lagrangian methods. Most of them have interesting interpretations as proximal point methods for solving the dual problem, when the original nonlinear programming problem is convex. In this paper a numerical comparison between many of these methods is performed using all the suitable problems of the CUTE collection. [ABSTRACT FROM AUTHOR]

Comparative molecular field analysis (CoMFA)and comparative molecular similarity indices analysis (CoMSIA) were performed on a set of pyridinone derivatives. A molecular alignment obtained by docking of compounds into the non-nucleoside reserve transcriptase inhibitor binding site of HIV-1 was used. Good correlations between the calculated binding free energies and experimental inhibitory activities suggest that the binding conformations of these inhibitors are reasonable. Robust and predictive 3D-QSAR models were obtained with q²values of 0.706 and 0.723 for CoMFA and CoMSIA, respectively. The models were validate by an external test set obtaining r²pred value of 0.720 and 0.750 for CoMFA and CoMSIA, respectively. The CoMSIA and docking results help to understand the type of interactions that occur between pyridinone derivatives with the non-nucleoside reverse transcriptase inhibitor binding pocket, and explain the viral resistance to pyridinone derivatives upon mutation of amino acids Tyr181 and Tyr188. The results obtained provide information for a better understanding of the drug resistance mechanism. The 3D-QSAR models derived will be used to guide the design of pyridinone derivatives active against mutant strains reverse transcriptase. [ABSTRACT FROM AUTHOR]

Field resistance to late blight – a fungal disease caused by Phytophthora infestans – has been genetically characterized by analyzing trait-marker association in a Solanum phureja (phu)×dihaploid Solanum tuberosum (dih-tbr) population. Trait data were developed at three locations over a 3-year period under natural infection pressure. RAPD (random amplified polymorphic DNA) and AFLP (amplified fragment length polymorphism)markers were used to develop anonymous genetic linkage groups subsequently anchored to potato chromosomes using mapped RFLP (restriction fragment length polymorphism), SSR (single sequence repeats) and AFLP markers. RFLP and SSR markers achieved the most-accurate anchoring. Two genetic maps were obtained, with 987.4 cM for phu and 773.7 cM for dih-tbr. Trait-marker association was revealed by single-marker and interval mapping analyses. Two important QTLs (quantitative trait loci) were detected on chromosomes VII and XII as a contribution from both parents, totalling up to 16% and 43%, respectively, of the phenotypic variation (PH). One additional QTL was detected on chromosome XI (up to 11% of the PH) as a contribution from the phu parent, and three others were detected on chromosome III (up to 13% of the PH), chromosome V (up to 11% of the PH) and chromosome VIII (up to 11% of the PH) as a contribution from the dih-tbr parent. Our results reveal new genetic loci of the potato genome that contribute to resistance to late blight. We postulate that some of these loci could be related to plant growth under short-day conditions. [ABSTRACT FROM AUTHOR]

Mantle cell lymphoma (MCL) is a tumor of intermediate-size, IgM+, IgD+ B cells derived from the mantle zone of the germinal center. Little is known about its specific immunologic features or responsiveness to T cell-derived signals. In this work, we evaluated the proliferation and cell cycle properties of freshly isolated MCL cells after CD40 ligation, in the absence and presence of interleukin 4 (IL-4). In each MCL case examined, there was a marked growth-enhancing effect of these two stimuli characterized by improved viability, augmented expression of Ki-67, and induction of the proliferating cell nuclear antigen (PCNA). Cyclin D1 was expressed throughout the cell cycle in MCL cells induced to enter S phase. From these investigations, we conclude that the biology of MCL B lymphocytes is affected by CD154 (CD40 ligand) and IL-4, two signals usually provided by CD4+ T cells. The capacity to manipulate the activation and cell cycle state of MCL cells by these specific immunological stimuli may be exploited to confer susceptibility to chemotherapy agents and develop novel therapies in this disease. [ABSTRACT FROM AUTHOR]

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We propose a G-foliated model of the seven-dimensional internal manifold M resulting from compactifying the N = 1, D = 11 model of supergravity of Cremmer, Julia and Scherk. This gives a generalisation of the usual G/H homogeneous-space approach. As a result, there is a natural way of expressing the internal spinor bundle as a graded tensor product. Under coordinate transformations mixing the tangential geometry with the transversal geometry of the foliation, spinors in this bundle with different internal helicities transform differently. We also argue that the ground-state compactifieation of the 11-dimensional manifold M into M × M is the result of a global submersion of M into M , giving rise to a foliation of dimension 7 and codimension 4. With these additional structures in place, we show that it is possible to incorporate physical chiral spinors into the original model while retaining the Riemannian geometry. There is also a canonical way of defining a Dirac operator on the internal spinor bundle, so that the mass spectrum of the internal Dirac operator is the sum of a tangential spectrum and a transversal spectrum. [ABSTRACT FROM AUTHOR]

Correlations between service induced microstructural degradation and creep properties in investment cast IN738LC turbine blades are discussed. Microstructural degradation in the form of γ' coarsen-ing, MC carbide degeneration, formation of continuous networks of grain boundary MC carbides, and the disappearance of serrated grain boundaries are considered in some detail. Their influence on primary ( t ,ε), secondary ( t , ε,ε) and tertiary (t, ε) creep behavior is analyzed through rela-tionships of the form: and These relationships are able to reveal service induced degeneration effects and can therefore be used to qualify rejuvenated blades. A systematic strategy for designing a HIPping rejuvenation cycle for Ni-base superalloys is presented. Once a rejuvenation cycle is designed, the above-mentioned relationships can then be used to analyze the extent of the rejuvenation of microstructure and creep properties in reheat-treated or hot isostatically pressed service exposed turbine blades. The influ-ence of trace amounts of Zr on creep properties of service exposed IN738LC turbine blades is also highlighted. [ABSTRACT FROM AUTHOR]

The present study examined the influence of chrome-aluminide coatings on the creep and stress rupture properties of a wrought Udimet-520 nickel-base superalloy used in gas turbine blade applications. Creep and stress rupture tests were conducted at 802 °C (1475 °F) on coated and uncoated wrought bars in the fully heat treated condition. The tests showed that the application of the chrome-aluminide coatings caused a marked deterioration in rupture strength and ductility. Masking procedures used to protect the turbine blade roots during coating of the Ni-base superalloy also affected the rupture strength or rupture ductility. The mechanical behavior in the coated creep resistant alloy was correlated with the microstructure and is discussed in terms of possible controlling processes. [ABSTRACT FROM AUTHOR]

The lethality and mutagenicity in ethyl methanesulfonate (EMS)-treated cells of five archaebacterial strains belonging to each of the three described genera of non-alkaliphilic halobacteria were investigated. In order to test the efficiency of the mutagenesis under a variety of experimental conditions, we chose the fast-growing halobacterium Haloferax mediterranei as a model strain. A strong induced mutagenicity was found, since the spontaneous mutation rate (expressed as the rate of resistance to the antibiotic josamycin) increased up to 500-fold after mutagen exposure. The mutagenesis was also successfully used in obtaining auxotrophic mutants. Although a heterogeneous response to the induced effects caused after EMS exposure was detected for the other halophilic archaebacteria tested, a clear, efficient mutagenicity of Halobacterium halobium and Haloferax gibbonsii was observed; auxotrophic mutants of this halobacterium were also produced. Optimal experimental conditions for EMS mutagenesis of some halobacteria were determined. [ABSTRACT FROM AUTHOR]

The lethal and mutagenic effects of hydroxylamine on Haloferax mediterranei and five other extremely halophilic archaebacteria are described for the first time. Although previous studies have shown that H. mediterranei was very resistant to the lethal action of other DNA-damaging agents, this strain was found to be relatively sensitive to hydroxylamine, but also more successfully mutated by the latter. The efficiency of the mutagenicity obtained with the hydroxylamine treatment was tested under a variety of conditions, and optimal procedures are described that yielded a number of useful auxotrophic mutant strains of H. mediterranei. Likewise, a strong induced mutagenicity after hydroxylamine mutagenesis was achieved for the majority of the other archaebacteria tested. [ABSTRACT FROM AUTHOR]

Von Willebrand factor (vWF), fibronectin (FN) and 13-hydroxy-octadecadienoic acid (13-HODE) are known to influence the regulation of the adhesive properties of vascular surfaces. In the present study vWF, FN and 13-HODE were comparatively localized in endothelial cells (EC) and in the extracellular matrix (ECM) produced by EC. An indirect immunofluorescent technique was applied to coverslips containing human EC cultures previously fixed and permeabilized following different procedures: A. Alcohol/acetone; B. Paraformaldehyde alone and C. Paraformaldehyde followed by Triton X-100. vWF was observed inside EC ( A), on the ECM produced by EC ( B) or in EC and ECM ( C) depending on the fixation procedures used. FN was mainly localized in the ECM despite the fixation procedures employed. FN was only seen in relation to cell bodies after strong permeabilization ( A). Under our experimental conditions 13-HODE was never found in ECM. This latter antigen was observed randomly dispersed in those preparations fixed with alcohol/acetone, indicating that it is probably extracted by this fixative. 13-HODE was detected in granular shaped structures in EC after permeabilization with detergent ( C). These results suggest that the cellular localization of vWF and FN is compatible with an adhesive role related to the abluminal side of ECs. 13-HODE was readily observed after mild permeabilization. This finding would be morphologically consistent with its contribution to the regulation of the vessel wall thromboresistance. [ABSTRACT FROM AUTHOR]

Experimental spinal cord trauma was produced in 3-month-old SS-1 minature pigs by dropping a 25 g weight from a height of 20 cm upon the exposed spinal cord. The histological lesion consisted of edema and hemorrhage. Phospholipid concentration and composition, cholesterol concentration and phospholipid fatty acid composition were determined in whole spinal cord 3 hours after injury, and in spinal cord myelin 5 hours after injury. Three hours after injury phospholipid and cholesterol concentration were decreased by about 14% in the whole spinal cord. Trauma had no effect on the phospholipid composition of whole spinal cord and myelin. Fatty acid composition of myelin also did not change after injury, and changed very slightly in the whole spinal cord. It is concluded that edema following spinal cord trauma is much more extensive than previously assumed. Furthermore, peroxidation of membrane lipid fatty acids does not appear to be a significant factor in spinal cord pathology 3 hours after injury. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate pretreatment prognostic factors that could be useful in predicting the response to plasma exchange in thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS). Thirty-two patients with TTP/HUS, treated with plasma exchange at our institution from 1980 to 1994, were studied. The main clinical and laboratory data at the beginning of plasma exchanges were analyzed by the Cox stepwise logistic regression, applied to either treatment failure or death. Seventeen (53%) patients attained a complete remission and 22 (69%) survived (five in advanced renal failure and long-term hemodialysis). Longer delay in initiating plasma exchanges, presence of stupor or coma, and higher creatinine levels at the beginning of plasma exchanges were independent predictors of treatment failure. Stupor or coma at the beginning of plasma exchanges was the only predictor of mortality from unremitted TTP/HUS. Hemoglobin levels, platelet count, and LDH activity, traditionally envisaged as markers of disease activity, neither correlated with previous duration of TTP/HUS nor had any prognostic value. Early diagnosis of TTP/HUS and prompt initiation of intensive plasma exchange emerged from this study as the most effective interventions for improving the prognosis of TTP/HUS patients. [ABSTRACT FROM AUTHOR]

A 50-year-old woman with primary biliary cirrhosis developed immune hemolytic anemia and renal failure while receiving rifampicin for the treatment of refractory pruritus. Serological studies revealed the presence of rifampicin-dependent antibodies of the IgM class that, when tested against a wide panel of erythrocytes, had anti-I specificity. Subsequently, rifampicin was withdrawn and prednisone treatment instituted, this resulting in a rapid resolution of the hemolysis, whereas hemodialysis was required for recovery of the renal function. A role is suggested for the anti-I specificity of the antibodies in the development of renal failure associated with rifampicin therapy. [ABSTRACT FROM AUTHOR]

Purpose of Review: Renal masses are a wide entity and a common finding in clinical practice. Detection of these masses has increased in the last years, yet mortality rates have slightly decreased.Recent Findings: According to the World Health Organization classification, there are 8 types, 51 subtypes, and a lot more subsequent subclassifications of renal tumors. Histopathological analysis should always be assessed for final diagnosis of theses tumors. However, imaging can be an important diagnostic guidance. The most common diagnoses of renal tumor are clear cell carcinoma, papillary renal cell carcinoma, angiomyolipoma, and transitional cell carcinoma. Nonetheless, a considerable variety of particular tumors can arise from the kidney, challenging the expertise of radiologists and urologists on this subject.Summary: The awareness of these unusual entities is vital for professionals working at a complex medical facility with greater volume of patients. We hereby present uncommon renal tumors and its pathological and radiological features. [ABSTRACT FROM AUTHOR]

Structural characterization at the nanometric scale of the Nautilus sp shell was carried out by high-resolution transmission electron microscopy and high-angle annular dark field to understand how the organic and inorganic components are related. The inorganic phase that built the shell is made of calcium carbonate (CaCO3), with the orthorhombic unit cell of the aragonite, in a texturized arrangement in such a way that the c-axis is always perpendicular to the shell surface. The organic material forms films through the plates. We observed for a very first time some aragonite nanocrystals embedded in the organic matrix. This observation supports the hypothesis that the proteins and other organic compounds guide the crystal growth because the organic matrixes are the places where the nanocrystals grow. [ABSTRACT FROM AUTHOR]