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Steelmaking industry generates a large volume of by-products that not always can be reintroduced into production processes, such as the steelmaking process itself or the production of cement. This is the case of ladle furnace slag (LFS), whose potential use is limited and usually ends up in landfill. This work investigates the feasibility of using LFS as binder for clayey soils stabilization in substitution of lime. The main parameters evaluated are plasticity index, California Bearing Ratio (CBR) and Unconfined Compressive Strength (UCS). The results show that the strength behavior of the mixtures is remarkable, obtaining increases in the CBR index between 8-14 times above unmodified clays. The mechanical performance base on UCS results show improvements of 85 % relative to natural soils three days after mixing. Moreover, if the curing time is up to 90 days, the UCS doubles or triples its value. Depending on the chemical composition of the soils, the performances of the mixtures are different, but in all cases the results are positive and encourage further research for the incorporation of ladle furnace slag as stabilizing agent.

A surface layer of permeable bituminous mixture has been laid on an existing pavement section. This layer, in addition to providing the pavement with draining characteristics and acoustic comfort, incorporates a residue that is difficult to apply, the ladle furnace steel slag. The tests carried out show that the designed mixture meets the requirements in terms of mechanical properties, resistance to the action of water, and porosity. Furthermore, in-situ tests on the completed layer demonstrate its excellent permeability, as well as a surface texture suitable for use on roads and highways. The introduction of the ladle furnace slag makes it possible to design a high-performance, but also environmentally sustainable, mix.

The hammer rebound index has traditionally been solely and exclusively used to estimate the compressive strength of vibrated concrete. Its use has recently been extended to the prediction of the compressive strength of Self-Compacting Concrete (SCC) and concrete produced with Recycled Concrete Aggregate (RCA). The conventional use of the hammer-rebound test is further developed in this paper, by demonstrating how it can be used to estimate the overall mechanical behavior of SCC containing RCA. To do so, nine SCC mixes with different contents and fractions (coarse, fine, and powder) of RCA are analyzed. Following a simple-linear-regression validation and property standardization procedure, the hammer rebound index is then expressed as a linear combination of four mechanical properties, adjusted through a multiple regression. The hammer rebound index is therefore expressed as a weighting of both the mean value of compressive behavior (arithmetic mean of compressive strength and modulus of elasticity) amounting to a weight of 72.8%, and the mean value of bendingtensile behavior (arithmetic mean of splitting tensile strength and flexural strength) amounting to a weight of 27.2%. The hammer rebound index can therefore be construed as an overall-mechanical-quality performance indicator of the SCC containing RCA, which can also yield predictions of every mechanical property. In this way, the application of the hammer rebound index could likewise be of use in rehabilitation, pathology, and healthmonitoring works where a full characterization of the mechanical performance of SCC with RCA is required, facilitating the use of SCC with RCA in real structures., The authors wish to express their gratitude to the following government ministries, agencies, and universities for funding this research: the Spanish Ministry of Universities, MICIN, AEI, EU, ERDF and NextGenerationEU/ PRTR [PID2020-113837RB-I00; 10.13039/501100011033; TED2021- 129715B-I00; FPU17/03374; PRX21/00007]; the Junta de Castilla y León (Regional Government) and ERDF [UIC-231, BU119P17]; the University of Burgos [SUCONS, Y135.GI]; and, finally, the University of Padova.

Objective To establish the prevalence of lesions of the labrum and articular cartilage of the hip in asymptomatic elite soccer players by performing 3T magnetic resonance imaging. Methods Eighty-four asymptomatic hips of 42 professional soccer players were evaluated. Male subjects older than 18 years were included. Cam and pincer deformity were defined as an alpha angle greater than 55 degrees and a lateral centre edge angle greater than 39 degrees, respectively. Labral injuries were classified with the Czerny classification and cartilage damage was classified with the Outerbridge classification. Specific statistical tests were used to establish the relationship between anatomical variances of the hip and the presence of chondral and labral injuries. Results FAI morphology prevalence was 25%. Abnormalities such as cam (22.5%) and labral injuries (33.8%) were found. Those cases with reported labral injury were predominantly intrasubstance damage (18.8%). Anatomical features of FAI were found to be related to lesions of the femoral cartilage (p Conclusion Asymptomatic labral or cartilaginous injuries of the hip were reported in 25% of the included professional soccer players. These injuries were associated with anatomical features of FAI.

Resumen Objetivo Establecer la prevalencia de lesiones del labrum y el cartilago articular de la cadera en futbolistas profesionales asintomaticos y explorar la asociacion con hallazgos en las pruebas de imagen de choque femoroacetabular (CFA). Metodos Estudio de corte transversal que evaluo por imagen de resonancia magnetica en 3 tesla (IRM 3 T) un total de 84 caderas en jugadores de futbol profesional, con edades entre los 18 y 31 anos. Se identificaron las lesiones del labrum y las del cartilago acetabular y femoral. Pruebas estadisticas especificas fueron utilizadas para establecer la relacion entre las alteraciones anatomicas de CFA y la presencia de lesiones condrolabrales. Resultados La prevalencia de CFA fue del 25%, siendo el tipo cam el mas predominante con 22,5%. Para las lesiones del labrum existe una prevalencia de 33,8%, de las cuales el 18,8% fueron para degeneracion intrasustancial y 2,5% para rotura completa. Las caracteristicas anatomicas de la cadera segun el tipo de CFA estan asociadas con lesiones del cartilago femoral p Conclusion Existe una alta prevalencia de lesiones asintomaticas del labrum y del cartilago articular de la cadera en futbolistas profesionales, las cuales se asocian a las caracteristicas anatomicas de CFA de cadera.

The compressive strength of recycled concrete is acknowledged to be largely conditioned by the incorporation ratio of Recycled Concrete Aggregate (RCA), although that ratio needs to be carefully assessed to optimize the design of structural applications. In this study, Self-Compacting Concrete (SCC) mixes containing 100% coarse RCA and variable amounts, between 0% and 100%, of fine RCA were manufactured and their compressive strengths were tested in the laboratory for a statistical analysis of their strength variations, which exhibited robustness and normality according to the common statistical procedures. The results of the confidence intervals, the one-factor ANalysis Of VAriance (ANOVA), and the Kruskal&ndash, Wallis test showed that an increase in fine RCA content did not necessarily result in a significant decrease in strength, although the addition of fine RCA delayed the development of the final strength. The statistical models presented in this research can be used to define the optimum incorporation ratio that would produce the highest compressive strength. Furthermore, the multiple regression models offered accurate estimations of compressive strength, considering the interaction between the incorporation ratio of fine RCA and the curing age of concrete that the two-factor ANOVA revealed. Lastly, the probability distribution predictions, obtained through a log-likelihood analysis, fitted the results better than the predictions based on current standards, which clearly underestimated the compressive strength of SCC manufactured with fine RCA and require adjustment to take full advantage of these recycled materials. This analysis could be carried out on any type of waste and concrete, which would allow one to evaluate the same aspects as in this research and ensure that the use of recycled concrete maximizes both sustainability and strength.

SiO2 supported NaVOx catalysts have raised interest due to reports showing an increase in the selectivity to propene in propane oxidation; a process that may become an alternative to conventional petrochemical routes for producing this valuable olefin. In this work, the effects of pH, the concentration of vanadium in solution, [V]Sol, and of their interaction; i.e., non-additive effect, over the properties of Na-SiO2 used for the oxidation of propane under oxygen rich conditions were studied. In general, the studied experimental factors had no net effects over the difference between the nominal and final loadings of vanadium in the catalysts, the surface area, and porosity. However, all catalysts presented a ~50% decrease in surface area due to partial mesopore blocking reflected by a ~30% increase in the average pore diameter. On the other hand, NaVO3 microcrystals and particles constituted -NaVO3 and -NaVO3 were formed at acidic pH, whereas Na metavanadate nanoparticles were formed at pH=9.0. These nanoparticles transformed into an -NaVO3 type phase upon dehydration. The reducibility of the catalysts was a function of the impregnation pH, where the catalysts synthesized at pH=3.8 and 9.0 displayed similar reduction patterns but lower reducibility than those synthesized at pH=1.5. The produced patterns were correlated to the existence of a mixture of V5+ and V4+ species among which V4+ was prevalent for the catalysts synthesized at pH=3.8 and 9.0. Consequently, the basicity of the catalysts decreased with the increase in pH. The surface concentration of vanadium increased with the increase in the concentration of vanadium in solution, while the pH had a weak negative effect over the former. On the other hand, it was established that chemical surface state of oxygen in the synthesized catalysts was influenced weakly by the synthesis pH and, more importantly, by non-additive effects between the pH and the concentration of vanadium in solution. The latter was coherent with the detection of surface oxygen species related to the partial dissolution of the Na-SiO2 support; a phenomenon that seemed to be favored at acidic pH. The latter properties were correlated to changes in basicity. Concerning the catalytic performance, the catalysts synthesized at pH=9.0 displayed the best steady state performance in terms of the selectivity to propene and oxygen consumption. The collected evidence allowed corroborating that both the oxidative dehydrogenation of propane to propene and its combustion to CO and CO2 are kinetically controlled by the initial activation of one of the C-H bonds of propane. But, the production of CO2 depended on the level of consumption of O2; where, a surplus of the latter compared to the conversion of propane combusted the hydrocarbon into CO2. Such a finding agreed with what has already been established for supported vanadium oxides for hydrocarbon oxidation. An analysis of the Raman spectra of the spent catalysts suggested that under the applied reaction conditions, all catalysts were provided of an active phase mostly constituted by -NaVO3 type structures. Therefore, the observed differences in catalytic behavior were rather associated to changes in particle size, reducibility, and acidity.

Thioredoxin system–mediated persulfidation of Cys residues controls protein function and protects them from oxidative stress., Irreversible oxidation of Cys residues to sulfinic/sulfonic forms typically impairs protein function. We found that persulfidation (CysSSH) protects Cys from irreversible oxidative loss of function by the formation of CysSSO1-3H derivatives that can subsequently be reduced back to native thiols. Reductive reactivation of oxidized persulfides by the thioredoxin system was demonstrated in albumin, Prx2, and PTP1B. In cells, this mechanism protects and regulates key proteins of signaling pathways, including Prx2, PTEN, PTP1B, HSP90, and KEAP1. Using quantitative mass spectrometry, we show that (i) CysSSH and CysSSO3H species are abundant in mouse liver and enzymatically regulated by the glutathione and thioredoxin systems and (ii) deletion of the thioredoxin-related protein TRP14 in mice altered CysSSH levels on a subset of proteins, predicting a role for TRP14 in persulfide signaling. Furthermore, selenium supplementation, polysulfide treatment, or knockdown of TRP14 mediated cellular responses to EGF, suggesting a role for TrxR1/TRP14-regulated oxidative persulfidation in growth factor responsiveness.

Redox regulation of STAT3 is targeted by direct inhibition of TrxR1, illuminating a promising link for therapeutic development., Because of its key role in cancer development and progression, STAT3 has become an attractive target for developing new cancer therapeutics. While several STAT3 inhibitors have progressed to advanced stages of development, their underlying biology and mechanisms of action are often more complex than would be expected from specific binding to STAT3. Here, we have identified and optimized a series of compounds that block STAT3-dependent luciferase expression with nanomolar potency. Unexpectedly, our lead compounds did not bind to cellular STAT3 but to another prominent anticancer drug target, TrxR1. We further identified that TrxR1 inhibition induced Prx2 and STAT3 oxidation, which subsequently blocked STAT3-dependent transcription. Moreover, previously identified inhibitors of STAT3 were also found to inhibit TrxR1, and likewise, established TrxR1 inhibitors block STAT3-dependent transcriptional activity. These results provide new insights into the complexities of STAT3 redox regulation while highlighting a novel mechanism to block aberrant STAT3 signaling in cancer cells.

The construction sector is clearly one of the most pollutant at a global level and its consumption of natural resources is also enormous. Over recent years, heightened awareness of this issue within the construction sector has motivated changes within its working practice,seeking to reduce its environmental impacts and to mitigate the effects of climate change. The consumption of natural resources can be reduced in very different areas and special attention has been given to the substitution of Natural Aggregates (NA) in concrete design by replacing those aggregates with various waste coproducts. Siderurgic concrete is the name given to concrete manufactured with siderurgical aggregate from the steel-making industry. In this paper, test results on fiber-reinforced siderurgical concrete are reported. The concrete is manufactured with approximately 50% Electric Arc Furnace Slag (EAFS) aggregate by volume, for use in pavement applications. Steel and polypropylene fibers, amounting to approximately 0.5% by volume of the concrete mass, are also added to the mix. The durability properties of this concrete type are analyzed through freeze/thaw and moist/dry tests. Furthermore, the long-term behavior of the concrete is explained through its internal structure, using Mercury Intrusion Porosity (MIP) and low-vacuum Scanning Electron Microscopy (SEM) analyses. The results add further weight to the feasibility of using EAFS in replacement of NA in fiber-reinforced concrete for pavement construction.

Replacing natural raw materials with industrial by-products can increase the sustainability of Self-Compacting Concrete (SCC), although its fresh and hardened behavior will usually worsen. The benefits of increased sustainability must therefore outweigh any reduction in concrete flowability and strength. These aspects can be analyzed through Multi-Criteria Decision-Making (MCDM) algorithms. In all, 19 SCC mixes were studied. One reproduced commercial SCC (limestone filler and conventional cement), the others were produced with more sustainable materials: 100% coarse Recycled Concrete Aggregate (RCA); 0%, 50% or 100% fine RCA; 45% Ground Granulated Blast-furnace Slag (GGBS); and sustainable aggregate powders such as limestone fines 0/0.5 mm and RCA powder 0/0.5 mm. Decreased flowability at 15 and at 60 min, compressive strength, modulus of elasticity, carbon footprint, and cost of mix were all studied. Both the carbon footprint and the cost were calculated considering only the composition of the SCC, without including aspects that depend on each particular case study, such as transport distances. These aspects constituted the decision-making criteria of the MCDM analysis, under which 14 scenarios were evaluated with different requirements for SCC, using 3 different algorithms (TOPSIS, AHP, and PROMETHEE). The results suggested that the ideal choice for fast concreting is a combination of GGBS, 100% coarse RCA and limestone fines, although if SCC has to be transported to the concreting point, then conventional cement should be used. Strength and stiffness can be maximized by limiting the fine RCA content to 50%. Finally, considering a versatile choice, only SCC with coarse RCA, limestone fines, GGBS and 0% fine RCA could compete with conventional SCC. Adapting the design to minimize the detrimental effects of by-products is therefore essential to promote sustainable SCC that is also commercially competitive., Spanish Ministry MCIU, AEI and ERDF [grant numbers PID 2020-113837RB-I00; 10.13039/501100011033; FPU17/03374]; the Junta de Castilla y León (Regional Government) and ERDF [grant number UIC-231, BU119P17]; Youth Employment Initiative (JCyL) and ESF [grant number UBU05B_1274]; and, finally, the University of Burgos [grant number SUCONS, Y135.GI].

In its Historical Memory Law (October 2007), Spain recognized victims on both sides of its 1936–1939 Civil War and established entitlements for victims and descendants of victims of the war and the Franco regime that followed (1939–1975). The law requires authorities to remove Francoist symbols and signs from public buildings and spaces, rename streets and squares, and cleanse the public space of monuments and artifacts that glorify or commemorate the regime. By allowing exceptions on artistic, architectural, or religious grounds, however, the law triggered persistent public struggles over monuments, memorials, and outdoor sculptures. This article examines the implementation of the law in the city of Granada, via a case study relating to the removal of a sculpture honoring the founder of the Spanish Fascist movement, José Antonio Primo de Rivera. The controversy over the statue sparked a debate in Granada about the implementation of the law in the public space and raised questions about the role of text, material and visual culture in redesigning Linguistic Landscape by articulating contested memories.

In this paper, we examine the performance of several popular hydraulic computer models in predicting the magnitude and location of a hydraulic jump. The computer programs considered include the standard HEC-RAS one-dimensional (1-D) models, as well as computational fluid dynamics models. Other computer programs considered include one-, two-, and three-dimensional (2-D and 3-D) models of both the steady and unsteady flow types. The computational model results are compared with experimental data from two different laboratories. It is shown that a few of these commonly used computer models miss the prediction of the hydraulic jump entirely and produce water surface profiles that are not proper estimates. Although the laboratory tests are one-dimensional steady-state scenarios, the failure of some of the multi-dimensional computer models to predict the likely occurrence of the hydraulic jump, or even provide an indication that the flow conditions are favorable for a jump to occur, indicates that care ...

"The authors had an academic meeting to face the challenge to provide clean water and to dispose of wastewaters once treated to reduce pollution impacts and to recycle the treated effluent. Chemistry plays a substantial role to the solution of removing pollutants since chemical reactions are crucial to increase the final quality of the treated effluents. A viable option might be the installation of units using the artificial wetlands technology. There microbial consortia carry these chemical reactions. Two case studies were considered, Mexico and Cuba. An example of the use of artificial wetlands to solve the lack of sanitation facilities for Mexico City’s Tlalpan section is given using as example two prototype plants located near this neighbourhood so that climate conditions will not interfere in the chemical reactions. The equivalent is given for a zone Havana City considering the Almendares river and the environmental impact on it."

PURPOSE The aim of this study was to assess the efficacy and safety of sertraline compared with placebo in a good clinical practice trial conducted with major depressive disorder patients naive to selective serotonin reuptake inhibitors. METHODS This was a 10-week randomized, multicenter, placebo-controlled, double blind, superiority trial. Adult patients diagnosed with major depressive disorder (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria), total score of 19 to 36 in the 17-item Hamilton Depression Rating Scale (HAMD-17), were randomly allocated to sertraline (n = 39) or placebo (n = 38). Each patient received a fixed dose of sertraline 50 mg/d or placebo for 4 weeks. Afterward a flexible dose up to 200 mg/d was allowed if needed. The primary efficacy end point was clinical response defined as 50% score reduction in HAMD-17 at 10 weeks relative to baseline. Supplementary analysis was performed on HAMD-17 score change from baseline. FINDINGS The clinical response favored sertraline (72% vs 32%; relative risk, 2.27; 95% confidence interval, 1.37-3.78; P = 0.0006). A linear mixed model showed arm × time interaction was significant (likelihood ratio test χ on 7 df = 48.42, P < 0.0001). The HAMD-17 change score favored sertraline from week 8 onwards. The most frequent adverse events in the sertraline arm were headache, diarrheas, and weight loss. IMPLICATIONS In this trial, the benefit of sertraline compared with placebo appeared later than usual. The therapeutic process with a close doctor-patient relationship throughout the trial and the effect expectancy due to a new treatment might explain the response delay. TRIAL REGISTRATION RPCEC, ID no. 00000128.

To establish the prevalence of lesions of the labrum and articular cartilage of the hip in asymptomatic elite soccer players by performing 3T magnetic resonance imaging.Eighty-four asymptomatic hips of 42 professional soccer players were evaluated. Male subjects older than 18 years were included. Cam and pincer deformity were defined as an alpha angle greater than 55 degrees and a lateral centre edge angle greater than 39 degrees, respectively. Labral injuries were classified with the Czerny classification and cartilage damage was classified with the Outerbridge classification. Specific statistical tests were used to establish the relationship between anatomical variances of the hip and the presence of chondral and labral injuries.FAI morphology prevalence was 25%. Abnormalities such as cam (22.5%) and labral injuries (33.8%) were found. Those cases with reported labral injury were predominantly intrasubstance damage (18.8%). Anatomical features of FAI were found to be related to lesions of the femoral cartilage (P.001), chondrolabral damage (P=.042), or both injuries (P.001).Asymptomatic labral or cartilaginous injuries of the hip were reported in 25% of the included professional soccer players. These injuries were associated with anatomical features of FAI.

In order to describe changes in ice volume in the cryosphere, a differential equation mathematical model is used in this paper. The dominating effects of freezing and thawing in the cryosphere enable simplification of the heat transport equations. This results in a mathematical model that can be solved exactly and is useful in investigating other climatic components, which in turn may be similarly analyzed for possible Global Circulation Model (GCM) validation. Data forms representing temperature and ice volume during the Pleistocene are available and can be directly compared with the exact solution of the simplified differential equation used in this paper. The model parameters may then be adjusted to approximate the effects of climate change; the adjusted model then run in reverse time, to develop an alternative history of ice volume of the cryosphere to be compared with the actual data interpretations previously published in the literature. In this fashion, an assessment may be made as to possible climate impacts in the cryosphere.

Depth-duration analysis, such as accomplished for rainfall, can be useful in the analysis of infiltration of rainfall. The assessment of infiltration depth-duration in terms of return frequency is of interest. In this paper, depth-duration values of daily rainfall infiltration are estimated using the National Resources Conservation Service (NRCS) Curve Number (CN) approach for estimating daily runoff. The CN methods may be generally applicable to soils that are free draining. From the estimated history of daily infiltration, a depth-duration analysis is accomplished for all duration sizes from 1 day to 365 days. These annual outcomes are then analyzed as to a possible underlying probability distribution. For the rain gages considered, the depth-duration infiltration estimates (using the CN approach) appear to be normally distributed. From the fitted distribution, estimates of rare events of rainfall infiltration may be made, and possible linkage to earth movement events accomplished with respect to return frequency of infiltration, which in turn can aid in the design and risk assessment of fixed works involving soil water accumulation.

In this paper, a comparison is made of available rainfall data in a localized study area of Los Angeles County, California. This particular area has also been studied by the State of California Department of Water Resources (DWR), the National Weather Service (NWS) National Oceanographic and Atmospheric Administration (NOAA), and the Los Angeles County (LAC) Department of Public Works. All three of these cited governmental agencies independently analyzed the rainfall data to identify rainfall trends for the study area, and then prepared statistical analyses in order to develop estimates of return frequencies for various peak durations of rainfall, among other items of interest to hydrologists. Additionally, these three agencies have available two different analyses of the available data, resulting in updates to their respective published works. Consequently, six different statistical analyses are available for comparison and assessment. In this paper, an examination is made of these six statistical studies and some of the differences between the various analyses are identified and explained.

A mathematical model is developed to describe changes in ice volume in the cryosphere. Modeling the cryosphere may be useful in assessing future climate impacts currently captured by global circulation models (GCMs) by providing an opportunity to validate GCMs. Leveraging the dominating effects of freezing and thawing in the cryosphere to simplify relevant heat transport equations allows for the derivation of a mathematical model that can be solved exactly. Such exact solutions are useful in investigating other climatic components that may be similarly analyzed for possible GCM validation. The current trend in GCM advancement is to increase the complexity and sophistication of the various heat transport effects that are represented in the governing mathematical model in cumulative form as the heat forcing function. In this paper, simplified models are developed whose solution can be directly compared with available data forms representing temperature and ice volume during the Pleistocene. With car...

Background: The orally available BRAF kinase inhibitor vemurafenib, compared with dacarbazine, shows improved response rates, progression-free survival (PFS), and overall survival in patients with metastatic melanoma that has a BRAFV600 mutation. We assessed vemurafenib in patients with advanced metastatic melanoma with BRAFV600 mutations who had few treatment options. Methods: In an open-label, multicentre study, patients with untreated or previously treated melanoma and a BRAFV600 mutation received oral vemurafenib 960 mg twice a day. The primary endpoint was safety. All analyses were done on the safety population, which included all patients who received at least one dose of vemurafenib. This report is the third interim analysis of this study. This study is registered with ClinicalTrials.gov, number NCT01307397. Findings: Between March 1, 2011, and Jan 31, 2013, 3226 patients were enrolled in 44 countries. 3222 patients received at least one dose of vemurafenib (safety population). At data cutoff, 868 (27%) patients were on study treatment and 2354 (73%) had withdrawn, mainly because of disease progression. Common adverse events of all grades included rash (1592 [49%]), arthralgia (1259 [39%]), fatigue (1093 [34%]), photosensitivity reaction (994 [31%]), alopecia (826 [26%]), and nausea (628 [19%]). 1480 (46%) patients reported grade 3 or 4 adverse events, including cutaneous squamous cell carcinoma (389 [12%]), rash (155 [5%]), liver function abnormalities (165 [5%]), arthralgia (106 [3%]), and fatigue (93 [3%]). Grade 3 and 4 adverse events were reported more frequently in patients aged 75 years and older (n=257; 152 [59%, 95% CI 53-65] and ten [4%, 2-7], respectively) than in those younger than 75 years (n=2965; 1286 [43%, 42-45] and 82 [3%, 2-3], respectively). Interpretation: Vemurafenib safety in this diverse population of patients with BRAFV600 mutated metastatic melanoma, who are more representative of routine clinical practice, was consistent with the safety profile shown in the pivotal trials of this drug. Funding: F Hoffmann-La Roche. © 2014 Elsevier Ltd.

A quasi one-dimensional kinetic Ising-like model is developed to study relaxation phenomena in linear polymer chains. In the case where the number N of bonds in the chain is very large, the model Hamiltonian reduces to the one giving the intramolecular energy of the Gibbs-di Marzio lattice model. The equations governing the dynamics of the different correlation functions are derived for this model and used to study relaxation phenomena in the system in the long-chain limit. First, the dielectric response where two cases are considered, namely, a single dipole placed in the middle of the chain and N non-interacting dipoles. In both cases a Debye behaviour is obtained. The effect of the temperature is introduced by considering a temperature-dependent relaxation time and surprisingly good agreement between the temperature dependence of the frequency of the maximum of the loss curve as computed with the model and experimental data of PMA and PVAC is obtained. Second, the relaxational heat capacity is analogously calculated; in this case, however, although the parameters used in the actual computations correspond to PMA and PVAC, respectively, no comparison with actual experimental results was feasible. One finds that here the behaviour is not Debye and no simple universality arises from the theoretical predictions.

The South American plains vizcacha, Lagostomus maximus, displays an exceptional ovulation rate of up to 800 eggs per cycle, the highest rate recorded for a mammal. Massive polyovulation arises from the overexpression of the apoptosis-inhibiting BCL2 gene leading to a suppression of apoptotic pathways responsible for follicular atresia in mammals. We analyzed the ovarian histology, ovarian apoptosis, and apoptosis-related protein expression with special emphasis in corpora lutea throughout the 5-mo-long gestation period, at parturition day and early postpartum, in L. maximus. Corpora lutea were abundant throughout gestation with no sign of structural regression even at the end of gestation. Both immunohistochemistry and Western blot analysis showed strong signals for apoptosis-inhibiting BCL2 protein, whereas the proapoptotic BAX protein was just detected in isolated luteal cells in gestating females and postpartum females. Apoptosis-associated DNA fragmentation detected by TUNEL was very scarce and occasional and correlated with BAX detection in luteal cells. Marked expression of progesterone and alpha-estrogen receptors in luteal cells was found at early, mid-, and late gestation as well as at parturition day and early postpartum samples. Additionally, serum level of progesterone increased markedly to reach maximal values at late gestation and decreasing at parturition to levels found at early gestation, suggesting that corpora lutea remained functional throughout gestation. These results point out that the unusual ovarian environment of L. maximus in which germ cell demise is abolished through antiapoptotic BCL2 gene overexpression also preserves structural integrity and functionality of corpora lutea during the whole gestation. Overexpression of antiapoptotic BCL2 gene may represent a strategy for an essential need of ovary and corpora lutea in order to maintain pregnancy until term.

The composition of the essential oil of Aristolochia brevipes Benth. has been investigated by GC and GC–MS. β-Pinene (20.6%), camphor (18.5%), dodecane (14.0%), 1,8-cineole (5.0%), and α-calacorene (5.0%) were the main components. The oil was characterized by the presence of a high percentage of monoterpene compounds. © 1997 John Wiley & Sons, Ltd.

Fifteen Rps genes confer resistance against the oomycete pathogen Phytophthora sojae, which causes root and stem rot disease in soybean. We have isolated a disease resistance gene-like sequence from the genomic region containing Rps1-k. Four classes of cDNA of the sequence were isolated from etiolated hypocotyl tissues that express the Rps1-k-encoded Phytophthora resistance. Sequence analyses of a cDNA clone showed that the sequence is a member of the coiled coil-nucleotide binding site–leucine rich repeat (CC-NBS–LRR)-type of disease resistance genes. It showed 36% identity to the recently cloned soybean resistance gene Rpg1-b, which confers resistance against Pseudomonas syringae pv. glycinea, and 56% and 38% sequence identity to putative resistance gene sequences from lotus and Medicago truncatula, respectively. The soybean genome contains about 38 copies of the sequence. Most of these copies are clustered in approximately 600 kb of contiguous DNA of the Rps1-k region. We have identified a recombinant that carries both rps1-k- and Rps1-k-haplotype-specific allelomorphs of two Rps1-k-linked molecular markers. An unequal crossover event presumably led to duplication of alleles for these two physically linked molecular markers. We hypothesize that the unequal crossing over was one of the mechanisms involved in tandem duplication of CC-NBS–LRR sequences in the Rps1-k region.

Alzheimer's disease (AD) is a pathological process characterized by neuron degeneration and, as recently suggested, brain plasticity. In this work, we compared the reactive plasticity in AD brains associated to O-glycosydically linked glycans, recognized by lectins from Amaranthus leucocarpus (ALL) and Macrobrachium rosenbergii (MRL), and the tau neuritic degeneration. The neuritic degenerative process was evaluated by the quantification of aggregated neuritic structures. Lesions were determined using antibodies against hyperphosphorylated-tau (AD2), amyloid-beta, and synaptophysin. In these conditions, we classified and quantified three pathological structures associated to the neuritic degenerative process: 1) Amyloid-beta deposits (AbetaDs), 2) Classic neuritic plaques (NPs), and 3) Dystrophic neurites clusters (DNCs) lacking amyloid-beta deposits. Reactive plasticity structures were constituted by meganeuritic clusters (MCs) and peri-neuronal sprouting in neurons of the CA4 region of the hippocampus, immunoreactive to synaptophysin (exclusively in AD brains) and GAP-43. Besides, MCs were associated to sialylated O-glycosydically linked glycans as determined by positive labeling with ALL and MRL. Considering that these lectins are specific for the synaptic sprouting process in AD, our results suggest the co-occurrence of of several areas of reactive plasticity and neuron degeneration in AD.

Optimal conditions for pharmacological induction of ovulation of vesper mouse, Calomys musculinus, were analyzed. The best superovulation (a mean of about 21 eggs per female, range 12-45) was induced by the administration of 12 IU of PMSG followed 48 hr later by injection of 15 IU of hCG. Ovulation started about 10 hr after administration of hCG and was completed during the next 4-5 hr. The induction of ovulation was achieved irrespective of the stage of the oestrus cycle at the moment of PMSG administration. The majority of females (105, 82.7%) responded to the treatment with either an ovulatory (53.4%) or superovulatory (49.7%) response. Oocyte recovery and egg quality were clearly influenced by the age of females, 30 days to more than 120 days old. The majority (90.3%) of superovulated eggs was morphologically normal, and only a small proportion of eggs showed morphological abnormalities (7.4%) or were spontaneously activated (2.3%). Superovulated oocytes under these conditions, were able to undergo normal fertilization in vitro. After 6 hr of sperm-egg interaction in vitro, 87.5% of the oocytes had extruded the second polar body and/or developed pronuclei.

Two patients with the congenital form of the long QT syndrome and polymorphous ventricular tachycardias unresponsive to adrenergic beta-blockade, were successfully treated with permanent pacemaker. We discuss the role of cardiac stimulation with pacemakers in the context of all the therapeutic modalities, taking into account the recent knowledge of chromosomal alterations and also in ionic channels.

A premature 3 days-old female with AV block Möbitz type II and structurally normal heart is presented. Progressive atrial abnormal repolarization was observed. Besides, transient total electrical alternans that included P wave, QRS complex, ST segment and T wave was evident. Retrospective analysis on ECG findings showed multiple metabolic and electrolytic disturbances related with this phenomenon. Hypoxia, hypothermia and long QT interval around an immature heart are particularly discussed as triggering factors.

Ten patients with AIDS and voiding disorders were assessed to determine the most common type of lower urinary tract dysfunction and its possible usefulness in detecting neurological disease.A complete urodynamic evaluation was performed.The most common symptom was urge incontinence and the most common urodynamic finding was detrusor-external sphincter dyssynergia. Of the 5 patients found to have a neurological disorder, only 3 had demonstrable functional disorder of the lower urinary tract (2 patients had detrusor hyperreflexia: one of them had a history of encephalopathy from HIV and the other patient had polyneuritis; the third patient had myelitis and a urodynamically diagnosed sympathetic decentration.Knowing the functional disorders of patients with AIDS can avoid complications and improve patient quality of life. Furthermore, it can be useful in detecting an existing neurological lesion or one that may develop in the future.