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New epoxy thermosets have been prepared via cationic UV-photopolymerization introducing two different multiarm star-like polymers. Both stars have a poly(glycidol) core but one has poly(methylmetacrylate) arms and the other poly(ζ--caprolactone) ones. The characterization of the curing process has been performed by Real-Time FTIR and photo-DSC, observing a slight reduction in the curing rate on increasing the proportion of star. The thermosets prepared were characterized by gel content determination, DMTA and TGA, and finally the morphology observed by FE-SEM, demonstrating the formation of nanophases in the case of the star with poly(ζ--caprolactone) arms. POLYM. ENG. SCI., 54:17-23, 2014. © 2013 Society of Plastics Engineers, INTRODUCTION Epoxy resins are one of the most used thermosets in the field of coatings. They are versatile materials that present high chemical resistance and good mechanical and thermal properties [...]

The effect of adding a multiarm star poly(styrene)-b-poly(ϵ-caprolactone) polymer on the cationic thermal and photoinitiated curing of diglycidyl ether of bisphenol A was studied. This star-polymer decelerated the thermal curing of diglycidyl ether of bisphenol A and modified the final structure of the epoxy matrix. The photocuring was influenced significantly by the addition of the multiarm star. When the proportion of this modifier added was 5%, much more time was necessary for complete photocuring (160 min at 40°C). In the presence of 10% of modifier, the degree of photocuring reached was very low (0.196 at 120°C). A subsequent thermal post-curing was necessary to cure completely the system. During photocuring in presence of poly(styrene)-b-poly(ϵ-caprolactone), the formation of dormant species, which are reactivated when the temperature increases, takes places. The kinetics of the thermal curing and the photocuring was analyzed using an isoconversional method due to the complexity of the reactive process. Applying this method, it has been confirmed the dependence of activation energy on the degree of conversion. The fracture morphology analyzed by scanning electron microscopy exhibited a second phase originated during photocuring by the presence of the modifier. [ABSTRACT FROM AUTHOR]

Describing the auditory periphery of odontocetes is a key conservation issue to further assess the effect of acoustic pollution. Because all odontocetes produce species-specific frequency ranges, differences in echolocation signals should reflect anatomical differences in the auditory pathways. Here, we studied the ears of 15 odontocete species through 3D reconstructions from computerized tomography scans to extract standard measurements (bullae lengths/volumes and cochlear volume) and investigate the discriminatory weight of each of these variables as well as their relation to the species' hearing specificity. Any of the measurements appeared to be a good indicator of the species and could therefore be used to classify them. All the ear lengths and most volumes were strongly linearly correlated (r >0.9) in all species and the proportion between the tympanic and periotic bones appeared to remain constant. This constant ratio could be an indication of a functional relationship between both structures, and might suggest an active role of the odontocete middle ear during target acoustic detection, providing new information on the odontocete sound reception mechanism. Our results are generally consistent with previous studies, although here the coefficients of correlation between animal lengths and the total volume and lengths of the bullae were lower (0.77< r <0.86), indicating that the length of the animals may not be a primary parameter to take into account when defining ear measurements. These results suggest that the measurements described characterize standard ears which could be used as a morphological basis for further species-specific acoustic comparison. [ABSTRACT FROM PUBLISHER]

Genes for an isoamylase-like debranching enzyme have been isolated from rice and Aegilops tauschii, the donor of the D genome to wheat. The structures of the genes are very similar to each other and to the maize SU1 isoamylase gene and consist of 18 exons spread over approximately 7.5 kb. Southern analysis and flourescent in situ hybridization showed the Ae.tauschii gene to be located in the proximal region of the short arm of chromosome 7D, thus showing synteny with the localization of the rice isoamylase gene on rice chromosome *. Analysis of the expression pattern of wheat sugary isoamylase genes indicates that they are strongly expressed in the developing endosperm 6 days after flowering. Three distinct Sugary-type cDNA sequences were isolated from the wheat endosperm that are likely to correspond to the products of the three genomes. The deduced amino acid sequence of rice and wheat Sugary-type isoamylase is compared with other sequences available in the database and the results demonstrate that there are three types of isoamylase sequences in plants: those containing 18 exons (the Sugary-type isoamylase gene), those containing 21 exons, and those containing only 1 exon. It is possible that different combinations of isoamylase genes are expressed in different tissues. [ABSTRACT FROM AUTHOR]

Objectives: Dysregulation of normal programmed cell death mechanisms plays an important role in the pathogenesis of breast cancer. The purpose of this study was to investigate the role of bax and p53 expression in tumorigenesis and progression of breast carcinoma as well as their relationship with proliferative and apoptotic activity. Methods: We used immunohistochemical methods and in situ detection of apoptotic cells to examine 30 carcinomas in situ (CIS), 131 invasive breast carcinomas and 45 lymph node metastases. Results: In 25% (33 of 131) of invasive breast carcinomas examined, bax expression was absent, while p53 accumulation was present in 37% (49 of 131). Interestingly, p53 accumulation and loss of bax expression occur in breast CIS as frequently as in invasive breast carcinoma. Thus, in 17% (5 of 30) of CIS bax expression was absent, and 30% (9 of 30) presented nuclear expression of p53. p53 accumulation was related to apoptosis and proliferative activity. However, the protein level of bax was unrelated to all parameters studied, including proliferation and apoptosis of tumor cells. A multivariate analysis of disease-free survival demonstrated that p53 accumulation and bax expression are not significant independent indicators of prognosis in operable breast carcinoma. Our results also show that the proportion of bax- and p53-positive cells does not vary between primary and metastatic tumors. Conclusions: p53 accumulation and loss of bax expression influence the acquisition of a malignant phenotype but seem to have no further impact on tumor progression. Copyright © 2003 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Myotonic muscular dystrophy (MMD) is a genetic disease caused by a defective enzyme, myotoninkinase. Male patients with MMD are reported to have reduced fertility. The purpose of this work was to study sperm capacitation and acrosome reaction in the ejaculates of sterile males with MMD and of healthy males (control group). The expression of the specific D-mannose receptors was explored by microscopic examination and by flow cytometry analysis. In addition, the binding patterns of Pisum sativum (PSA) lectin to acrosome content and outer acrosomal membrane in the spermatozoa of each group were analysed. Both the capacitation and the acrosome reaction in the spermatozoa of the MMD group were deficient and these findings strongly suggest that these anomalies may account for the sterility of these patients. [ABSTRACT FROM AUTHOR]

Myotonic muscular dystrophy (MMD) is a genetic disease caused by a defective enzyme, myotoninkinase. Male patients with MMD are reported to have reduced fertility. The purpose of this work was to study sperm capacitation and acrosome reaction in the ejaculates of sterile males with MMD and of healthy males (control group). The expression of the specific D-mannose receptors was explored by microscopic examination and by flow cytometry analysis. In addition, the binding patterns of Pisum sativum (PSA) lectin to acrosome content and outer acrosomal membrane in the spermatazoa of each group were analysed. Both the capacitation and the acrosome reaction in the spermatozoa of the MMD group were deficient and these findings strongly suggest that these anomalies may account for the sterility of these patients. [ABSTRACT FROM PUBLISHER]

Cognitive impairment is the main cause of disability in developed societies. New interactive technologies help therapists in neurorehabilitation in order to increase patients' autonomy and quality of life. This work proposes Interactive Video (IV) as a technology to develop cognitive rehabilitation tasks based on Activities of Daily Living (ADL). ADL cognitive task has been developed and integrated with eye-tracking technology for task interaction and patients' performance monitoring. [ABSTRACT FROM AUTHOR]

Abstract Background Mutational inactivation of plant genes is an essential tool in gene function studies. Plants with inactivated or deleted genes may also be exploited for crop improvement if such mutations/deletions produce a desirable agronomical and/or quality phenotype. However, the use of mutational gene inactivation/deletion has been impeded in polyploid plant species by genetic redundancy, as polyploids contain multiple copies of the same genes (homoeologous genes) encoded by each of the ancestral genomes. Similar to many other crop plants, bread wheat (Triticum aestivum L.) is polyploid; specifically allohexaploid possessing three progenitor genomes designated as 'A', 'B', and 'D'. Recently modified TILLING protocols have been developed specifically for mutation detection in wheat. Whilst extremely powerful in detecting single nucleotide changes and small deletions, these methods are not suitable for detecting whole gene deletions. Therefore, high-throughput methods for screening of candidate homoeologous gene deletions are needed for application to wheat populations generated by the use of certain mutagenic agents (e.g. heavy ion irradiation) that frequently generate whole-gene deletions. Results To facilitate the screening for specific homoeologous gene deletions in hexaploid wheat, we have developed a TaqMan qPCR-based method that allows high-throughput detection of deletions in homoeologous copies of any gene of interest, provided that sufficient polymorphism (as little as a single nucleotide difference) amongst homoeologues exists for specific probe design. We used this method to identify deletions of individual TaPFT1 homoeologues, a wheat orthologue of the disease susceptibility and flowering regulatory gene PFT1 in Arabidopsis. This method was applied to wheat nullisomic-tetrasomic lines as well as other chromosomal deletion lines to locate the TaPFT1 gene to the long arm of chromosome 5. By screening of individual DNA samples from 4500 M2 mutant wheat lines generated by heavy ion irradiation, we detected multiple mutants with deletions of each TaPFT1 homoeologue, and confirmed these deletions using a CAPS method. We have subsequently designed, optimized, and applied this method for the screening of homoeologous deletions of three additional wheat genes putatively involved in plant disease resistance. Conclusions We have developed a method for automated, high-throughput screening to identify deletions of individual homoeologues of a wheat gene. This method is also potentially applicable to other polyploidy plants.

Abstract Background Many enzymes of industrial interest are not in the market since they are bio-produced as bacterial inclusion bodies, believed to be biologically inert aggregates of insoluble protein. Results By using two structurally and functionally different model enzymes and two fluorescent proteins we show that physiological aggregation in bacteria might only result in a moderate loss of biological activity and that inclusion bodies can be used in reaction mixtures for efficient catalysis. Conclusion This observation offers promising possibilities for the exploration of inclusion bodies as catalysts for industrial purposes, without any previous protein-refolding step.

This paper deals with determining the linguistic competence of university students in EFL classes that are part of an English Studies degree. It suggests a language deficiency analysis (i.e., a combination of their target situation and their actual situation) to aid in the selection of language content to be taught. The proposed needs analysis makes use of the Oxford Placement Test (OPT), which is described as a sound standardized test for university EFL classes. The results obtained by students in the English Studies Department at the University of Alicante are used to explain how the OPT can be used to determine the students' linguistic competence, their language knowledge, their linguistic needs and their progress in linguistic competence.