996 resultados para multiple quantum wells


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Background: The analysis of the promoter sequence of genes with similar expression patterns isa basic tool to annotate common regulatory elements. Multiple sequence alignments are on thebasis of most comparative approaches. The characterization of regulatory regions from coexpressedgenes at the sequence level, however, does not yield satisfactory results in manyoccasions as promoter regions of genes sharing similar expression programs often do not shownucleotide sequence conservation.Results: In a recent approach to circumvent this limitation, we proposed to align the maps ofpredicted transcription factors (referred as TF-maps) instead of the nucleotide sequence of tworelated promoters, taking into account the label of the corresponding factor and the position in theprimary sequence. We have now extended the basic algorithm to permit multiple promotercomparisons using the progressive alignment paradigm. In addition, non-collinear conservationblocks might now be identified in the resulting alignments. We have optimized the parameters ofthe algorithm in a small, but well-characterized collection of human-mouse-chicken-zebrafishorthologous gene promoters.Conclusion: Results in this dataset indicate that TF-map alignments are able to detect high-levelregulatory conservation at the promoter and the 3'UTR gene regions, which cannot be detectedby the typical sequence alignments. Three particular examples are introduced here to illustrate thepower of the multiple TF-map alignments to characterize conserved regulatory elements inabsence of sequence similarity. We consider this kind of approach can be extremely useful in thefuture to annotate potential transcription factor binding sites on sets of co-regulated genes fromhigh-throughput expression experiments.

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Syngnathia is an extremely rare condition involving congenital fusion of the maxilla with the mandible. Clinical presentations vary from simple mucosal bands (synechiae) to complete bony fusion (synostosis). Most cases are unilateral incomplete fusions. We report the case of a severely growth-retarded newborn infant with complete synostosis of the mandible with the maxilla and the zygoma associated with cleft palate, choanal atresia, deafness, delayed cerebral white matter development, and genital and limb malformations. Extensive genetic analysis did not reveal any mutations. This association of multiple congenital malformations may represent an entity distinct from previously described syndromes associated with syngnathia.

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In this study, we show that a chemical dye, malachite green (MG), which is commonly used in the fish industry as an antifungal, antiparasitic, and antibacterial agent, could effectively kill Candida albicans and non-C. albicans species. We have demonstrated that Candida cells are susceptible to MG at a very low concentration (MIC that reduces growth by 50% [MIC(50)], 100 ng ml(-1)) and that the effect of MG is independent of known antifungal targets, such as ergosterol metabolism and major drug efflux pump proteins. Transcriptional profiling in response to MG treatment of C. albicans cells revealed that of a total of 207 responsive genes, 167 genes involved in oxidative stress, virulence, carbohydrate metabolism, heat shock, amino acid metabolism, etc., were upregulated, while 37 genes involved in iron acquisition, filamentous growth, mitochondrial respiration, etc., were downregulated. We confirmed experimentally that Candida cells exposed to MG resort to a fermentative mode of metabolism, perhaps due to defective respiration. In addition, we showed that MG triggers depletion of intracellular iron pools and enhances reactive oxygen species (ROS) levels. These effects could be reversed by the addition of iron or antioxidants, respectively. We provided evidence that the antifungal effect of MG is exerted through the transcription regulators UPC2 (regulating ergosterol biosynthesis and azole resistance) and STP2 (regulating amino acid permease genes). Taken together, our transcriptome, genetic, and biochemical results allowed us to decipher the multiple mechanisms by which MG exerts its anti-Candida effects, leading to a metabolic shift toward fermentation, increased generation of ROS, labile iron deprivation, and cell necrosis.

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The choice of a research path in attacking scientific and technological problems is a significant component of firms’ R&D strategy. One of the findings of the patent races literature is that, in a competitive market setting, firms’ noncooperative choices of research projects display an excessive degree of correlation, as compared to the socially optimal level. The paper revisits this question in a context in which firms have access to trade secrets, in addition to patents, to assert intellectual property rights (IPR) over their discoveries. We find that the availability of multiple IPR protection instruments can move the paths chosen by firms engaged in an R&D race toward the social optimum.

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This paper presents several algorithms for joint estimation of the target number and state in a time-varying scenario. Building on the results presented in [1], which considers estimation of the target number only, we assume that not only the target number, but also their state evolution must be estimated. In this context, we extend to this new scenario the Rao-Blackwellization procedure of [1] to compute Bayes recursions, thus defining reduced-complexity solutions for the multi-target set estimator. A performance assessmentis finally given both in terms of Circular Position Error Probability - aimed at evaluating the accuracy of the estimated track - and in terms of Cardinality Error Probability, aimed at evaluating the reliability of the target number estimates.

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The ways in which the dominant cultural majority frames the educationalsystem determine perceptions of its own identity and understandings ofthe ‘other.’ In this article I take a political approach, by examining themanagement of cultural diversity within Spanish education policies, treating“education as the mirror of society”. This article analyzes Spanish challengesand policies approaches towards the management of immigrationrelated diversity in education. The main finding is that there is not one approach,but several, due to both the decentralized character of the educationsystem and the multiplicity of diversity that is at stake (i.e. language,religion, culture etc.)

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INTRODUCTION: Mass casualty incidents involving victims with severe burns pose difficult and unique problems for both rescue teams and hospitals. This paper presents an analysis of the published reports with the aim of proposing a rational model for burn rescue and hospital referral for Switzerland. METHODS: Literature review including systematic searches of PubMed/Medline, reference textbooks and journals as well as landmark articles. RESULTS: Since hospitals have limited surge capacities in the event of burn disasters, a special approach to both prehospital and hospital management of these victims is required. Specialized rescue and care can be adequately met and at all levels of needs by deploying mobile burn teams to the scene. These burn teams can bring needed skills and enhance the efficiency of the classical disaster response teams. Burn teams assist with both primary and secondary triage, contribute to initial patient management and offer advice to non-specialized designated hospitals that provide acute care for burn patients with Total Burn Surface Area (TBSA) <20-30%. The main components required for successful deployments of mobile burn teams include socio-economic feasibility, streamlined logistical implementation as well as partnership coordination with other agencies including subsidiary military resources. CONCLUSIONS: Disaster preparedness plans involving burn specialists dispatched from a referral burn center can upgrade and significantly improve prehospital rescue outcome, initial resuscitation care and help prevent an overload to hospital surge capacities in case of multiple burn victims. This is the rationale behind the ongoing development and implementation of the Swiss burn plan.

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There is currently no approved neuroprotective pharmacotherapy for acute conditions such as stroke and cerebral asphyxia. One of the reasons for this may be the multiplicity of cell death mechanisms, because inhibition of a particular mechanism leaves the brain vulnerable to alternative ones. It is therefore essential to understand the different cell death mechanisms and their interactions. We here review the multiple signaling pathways underlying each of the three main morphological types of cell death - apoptosis, autophagic cell death and necrosis - emphasizing their importance in the neuronal death that occurs during cerebral ischemia and hypoxia-ischemia, and we analyze the interactions between the different mechanisms. Finally, we discuss the implications of the multiplicity of cell death mechanisms for the design of neuroprotective strategies.

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The Anyplex II HPV28 (H28; Seegene) is a new semiquantitative real-time multiplex PCR assay for screening and genotyping 28 human papillomaviruses (HPV) in only 2 reaction wells. H28 was compared to the PGMY-CHUV assay (PG) with 309 archival DNA samples from cervical smears collected over 8 years in our laboratory. H28 and PG were fully concordant at the genotypic level on 228 (73.8%) out of 309 samples: 27 HPV negative and 201 HPV positive. The 201 fully concordant positive samples corresponded to single infections (n = 145) and to multiple infections (2 genotypes, n = 38; 3 to 5 genotypes, n = 18). The remaining 81 samples (26.2%) were either partially concordant (n = 64, 20.7%) or fully discordant (n = 17, 5.5%). While genotype-specific agreement was nearly perfect (κ = 0.877), HPV51 was significantly less well detected by H28 and the converse was observed for HPV40, -42, -54, and -68. Sequencing of PG amplicons confirmed HPV51 discordants and suggested the involvement of a possibly local HPV51 subtype. Mismatches in the PGMY09 primers to HPV68a explained most of the HPV68 discordants, confirming the specificity of H28 toward HPV68. With PG as a reference, the sensitivity and specificity of H28 were 93.4% and 99.0%, respectively. Considering H28 as a reference, the sensitivity and specificity of PG were 83.8% and 99.6%, respectively. H28 is a very sensitive and specific HPV genotyping assay suitable for research and clinical use as an adjunct to a clinically validated test. H28 semiquantitative readout ought to be evaluated for primary cervical cancer screening.

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BACKGROUND: Multiple epiphyseal dysplasia (MED) is one of the more common generalised skeletal dysplasias. Due to its clinical heterogeneity diagnosis may be difficult. Mutations of at least six separate genes can cause MED. Joint deformities, joint pain and gait disorders are common symptoms. CASE PRESENTATION: We report on a 27-year-old male patient suffering from clinical symptoms of autosomal recessive MED with habitual dislocation of a multilayered patella on both sides, on the surgical treatment and on short-term clinical outcome. Clinical findings were: bilateral hip and knee pain, instability of femorotibial and patellofemoral joints with habitual patella dislocation on both sides, contractures of hip, elbow and second metacarpophalangeal joints. Main radiographic findings were: bilateral dislocated multilayered patella, dysplastic medial tibial plateaus, deformity of both femoral heads and osteoarthritis of the hip joints, and deformity of both radial heads. In the molecular genetic analysis, the DTDST mutation g.1984T > A (p.C653S) was found at the homozygote state. Carrier status was confirmed in the DNA of the patient's parents. The mutation could be considered to be the reason for the patient's disease. Surgical treatment of habitual patella dislocation with medialisation of the tibial tuberosity led to an excellent clinical outcome. CONCLUSIONS: The knowledge of different phenotypes of skeletal dysplasias helps to select genes for genetic analysis. Compared to other DTDST mutations, this is a rather mild phenotype. Molecular diagnosis is important for genetic counselling and for an accurate prognosis. Even in case of a multilayered patella in MED, habitual patella dislocation could be managed successfully by medialisation of the tibial tuberosity.

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We studied for the first time the occurrence of multiple paternity, male reproductive success, and neonate survival in wild, low-density adder (Vipera berus) populations using 13 microsatellite loci. Paternity was assigned for 15 clutches, collected during 3 years. Our data demonstrated that multiple paternity can occur at a high level (69%) in natural populations of V. berus, even if the density of adults is low. The high proportion of multiple sired clutches was comparable to the proportion observed in captive populations. Male reproductive success significantly increased with body length, and only the largest males successfully sired entire clutches. Finally, no relationship was detected between the number of fathers per clutch and neonate survival. These results suggest that multiple matings could be beneficial in populations with high level of inbreeding or low male fecundity.

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This final project was made for the Broadband/Implementation department of TeliaSonera Finland. The question to be examined is if the operator should replace multiple ADSL connections implemented over a leased line with Multi-Dwelling access based on an Ethernet/Optical Fibre access network. The project starts with describing the technology related to these access network solu-tions and presents the technology that is used in TeliaSonera Finland's access network. It continues from the technology to describe the problem with some of the ADSL implemen-tations of TeliaSonera. The problem is the implementations done over a leased line that can cost TeliaSonera over years as much as a possible investment to extend network when there is several lines leased to the same building. The project proposes a Multi-Dwelling access as a solution to this problem and defines the circumstances when to use it. After a satisfactory solution has found the project takes a view how implementation of the solution might alter the network and a new problem is found. When used commonly to replace need of ADSL implementation Multi-Dwelling access would significantly increase optical cable congestion near operators POP. As a final deed this project also proposes a technical change to existing way to implement multi-dwelling access with EPON technology.

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The aim of this thesis is to present a solution to the quantum phase problem of the single-mode optical field. The solution is based on the use of phase shift covariant normalized positive operator measures. These measures describe realistic direct coherent state phase measurements such as the phase measurement schemes based on eight-port homodyne detection or heterodyne detection. The structure of covariant operator measures and, more generally, covariant sesquilinear form measures is analyzed in this work. Four different characterizations for phase shift covariant normalized positive operator measures are presented. The canonical covariant operator measure is definded and its properties are studied. Finally, some other suggested phase theories are introduced to investigate their connections to the covariant sesquilinear form measures.

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OBJECTIVE: A single course of antenatal corticosteroids (ACS) is associated with a reduction in respiratory distress syndrome and neonatal death. Multiple Courses of Antenatal Corticosteroids Study (MACS), a study involving 1858 women, was a multicentre randomized placebo-controlled trial of multiple courses of ACS, given every 14 days until 33+6 weeks or birth, whichever came first. The primary outcome of the study, a composite of neonatal mortality and morbidity, was similar for the multiple ACS and placebo groups (12.9% vs. 12.5%), but infants exposed to multiple courses of ACS weighed less, were shorter, and had smaller head circumferences. Thus for women who remain at increased risk of preterm birth, multiple courses of ACS (every 14 days) are not recommended. Chronic use of corticosteroids is associated with numerous side effects including weight gain and depression. The aim of this postpartum assessment was to ascertain if multiple courses of ACS were associated with maternal side effects. METHODS: Three months postpartum, women who participated in MACS were asked to complete a structured questionnaire that asked about maternal side effects of corticosteroid use during MACS and included the Edinburgh Postnatal Depression Scale. Women were also asked to evaluate their study participation. RESULTS: Of the 1858 women randomized, 1712 (92.1%) completed the postpartum questionnaire. There were no significant differences in the risk of maternal side effects between the two groups. Large numbers of women met the criteria for postpartum depression (14.1% in the ACS vs. 16.0% in the placebo group). Most women (94.1%) responded that they would participate in the trial again. CONCLUSION: In pregnancy, corticosteroids are given to women for fetal lung maturation and for the treatment of various maternal diseases. In this international multicentre randomized controlled trial, multiple courses of ACS (every 14 days) were not associated with maternal side effects, and the majority of women responded that they would participate in such a study again.

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When continuous data are coded to categorical variables, two types of coding are possible: crisp coding in the form of indicator, or dummy, variables with values either 0 or 1; or fuzzy coding where each observation is transformed to a set of "degrees of membership" between 0 and 1, using co-called membership functions. It is well known that the correspondence analysis of crisp coded data, namely multiple correspondence analysis, yields principal inertias (eigenvalues) that considerably underestimate the quality of the solution in a low-dimensional space. Since the crisp data only code the categories to which each individual case belongs, an alternative measure of fit is simply to count how well these categories are predicted by the solution. Another approach is to consider multiple correspondence analysis equivalently as the analysis of the Burt matrix (i.e., the matrix of all two-way cross-tabulations of the categorical variables), and then perform a joint correspondence analysis to fit just the off-diagonal tables of the Burt matrix - the measure of fit is then computed as the quality of explaining these tables only. The correspondence analysis of fuzzy coded data, called "fuzzy multiple correspondence analysis", suffers from the same problem, albeit attenuated. Again, one can count how many correct predictions are made of the categories which have highest degree of membership. But here one can also defuzzify the results of the analysis to obtain estimated values of the original data, and then calculate a measure of fit in the familiar percentage form, thanks to the resultant orthogonal decomposition of variance. Furthermore, if one thinks of fuzzy multiple correspondence analysis as explaining the two-way associations between variables, a fuzzy Burt matrix can be computed and the same strategy as in the crisp case can be applied to analyse the off-diagonal part of this matrix. In this paper these alternative measures of fit are defined and applied to a data set of continuous meteorological variables, which are coded crisply and fuzzily into three categories. Measuring the fit is further discussed when the data set consists of a mixture of discrete and continuous variables.