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The spectrum of bound and scattering states of the one dimensional Dirac Hamiltonian describing fermions distorted by a static background built from two Dirac delta potentials is studied. A distinction will be made between 'mass-spike' and 'electrostatic' δ -potentials. The second quantisation is then performed to promote the relativistic quantum mechanical problem to a relativistic quantum field theory and study the quantum vacuum interaction energy for fermions confined between opaque plates. The work presented here is a continuation of (Guilarte et al 2019 Front. Phys. 7 109). [ABSTRACT FROM AUTHOR]

The mucosa of the female reproductive tract must reconcile the presence of commensal microbiota and the transit of exogenous spermatozoa with the elimination of sexually transmitted pathogens. In the vagina, neutrophils are the principal cellular arm of innate immunity and constitute the first line of protection in response to infections or injury. Neutrophils are absent from the vaginal lumen during the ovulatory phase, probably to allow sperm to fertilize; however, the mechanisms that regulate neutrophil influx to the vagina in response to aggressions remain controversial. We have used mouse inseminations and infections of Neisseria gonorrhoeae, Candida albicans, Trichomonas vaginalis, and HSV-2 models. We demonstrate that neutrophil infiltration of the vaginal mucosa is distinctively contingent on the ovarian cycle phase and independent of the sperm and pathogen challenge, probably to prevent sperm from being attacked by neutrophils. Neutrophils extravasation is a multi-step cascade of events, which includes their adhesion through selectins (E, P and L) and integrins of the endothelial cells. We have discovered that cervical endothelial cells expressed selectin-E (SELE, CD62E) to favor neutrophils recruitment and estradiol down-regulated SELE expression during ovulation, which impaired neutrophil transendothelial migration and orchestrated sperm tolerance. Progesterone up-regulated SELE to restore surveillance after ovulation. [ABSTRACT FROM AUTHOR]

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In this paper we study the system of a scalar quantum field confined between two plane, isotropic, and homogeneous parallel plates at thermal equilibrium. We represent the plates by the most general lossless and frequency-independent boundary conditions that satisfy the conditions of isotropy and homogeneity and are compatible with the unitarity of the quantum field theory. Under these conditions we compute the thermal correction to the quantum vacuum energy as a function of the temperature and the parameters encoding the boundary condition. The latter enables us to obtain similar results for the pressure between plates and the quantum thermal correction to the entropy. We find out that our system is thermodynamically stable for any boundary conditions, and we identify a critical temperature below which certain boundary conditions yield attractive, repulsive, and null Casimir forces. [ABSTRACT FROM AUTHOR]

The basic thermodynamic quantities for a non-interacting scalar field in a periodic potential composed of either a one-dimensional chain of Dirac δ - δ ′ functions or a specific potential with extended compact support are calculated. First, we consider the representation in terms of real frequencies (or one-particle energies). Then we turn the axis of frequency integration towards the imaginary axis by a finite angle, which allows for easy numerical evaluation, and finally turn completely to the imaginary frequencies and derive the corresponding Matsubara representation, which this way appears also for systems with band structure. In the limit case T → 0 we confirm earlier results on the vacuum energy. We calculate for the mentioned examples the free energy and the entropy and generalize earlier results on negative entropy. [ABSTRACT FROM AUTHOR]

We obtain new expressions for the Casimir energy between plates that are mimicked by the most general possible boundary conditions allowed by the principles of quantum field theory. This result enables to provide the quantum vacuum energy for scalar fields propagating under the influence of a one-dimensional crystal represented by a periodic potential formed by an infinite array of identical potentials with compact support. [ABSTRACT FROM AUTHOR]

La valoración de la respuesta a la terapia es una de las indicaciones más complejas de los estudios de imagen. Valorar la respuesta a la terapia de un paciente incluido en un ensayo clínico usualmente está sujeto a unos criterios de respuesta estandarizados para ese contexto. Sin embargo, en la práctica clínica habitual se realizan muchos estudios en los que la pregunta clínica es si el tratamiento que recibe el paciente está siendo o no efectivo. Responder a esta pregunta representa uno de los mayores retos de los especialistas en imagen, especialmente con la introducción de nuevas modalidades de tratamiento, cuyos efectos directos sobre el tejido tumoral son inicialmente poco conocidos. Tenemos un papel esencial en la introducción de nuevas terapias, valorando sus efectos y sus beneficios en las diferentes situaciones clínicas. El conocimiento de estos efectos ha llevado a desarrollar nuevos criterios de respuesta que, a pesar de ser aplicables únicamente en ensayos clínicos, nos ofrecen información de cómo interpretar los hallazgos en la práctica clínica. Therapy response assessment is one of the most challenging indications of imaging studies. In clinical trial patients is usually measured with standardized response criteria. However, in the clinical practice, many studies are carried out in which the clinical question is whether or not the treatment is being effective. Answering this question is one of the greatest challenges for diagnostic imaging physicians, especially when a new treatment modality is being introduced, whose effects on tumoral lesions are firstly poorly understood. We have an essential role in the introduction of new therapies, assessing their effects and benefits. The knowledge of these effects has led to the development of many response criteria that, despite being applicable only in clinical trials, offer us information on how to interpret the findings in clinical practice. [ABSTRACT FROM AUTHOR]

Cathodoluminescence and micro-Raman studies of GaAs on Si layers grown by the conformal method show a characteristic quasiperiodic modulation of the stress distribution perpendicular to the growth direction. Using the capability of the spectral imaging in the cathodoluminescence technique, the stress distribution has been directly mapped. The Raman data give accurate information of the stress level variations in the upper part of the samples, which compare well with the luminescence data. The origin of the quasiperiodic stress variations are discussed in terms of the growth geometry, taking account of the presence of a compliant thin SiO2 layer in between the Si substrate and the <110> growing GaAs layer. [ABSTRACT FROM AUTHOR]

Background: Nail psoriasis disease is associated with an increased probability of psoriatic arthritis, and its clinical signs may have different correlates with the pathogenesis of adjacent bone destruction and have different prognostic value. Recent publications about psoriasis and nail psoriatic disease describe different ultrasonographic findings but the relationship between these ungueal alterations measured by ultrasonography and the presence of enthesopathy of the extensor digitorum has yet to be discovered. Objective: To describe which ultrasonographic characteristics of nail psoriasis are associated with the presence of subclinical enthesopathy in patients with PsO and asymptomatic PsA. Methods: Patients with psoriasis and asymptomatic psoriatic arthritis were included in the prospective study. Demographic, clinical data and PASI and NAPSI indexes were recorded of all the patients in the assessment visit. The US assessment included Achilles tendon, extensor digitorum tendon and US scan of the nail plate, nail matrix, nail bed and adjacent skin over nail matrix of the five nails of each hand. Results: Forty‐eight patients were included in the study; 33 of them presented ultrasound evidence of extensor digitorum tendon enthesopathy. Nails of the patients with subclinical enthesopathy had a higher NAPSI and skin thickness than the nails of the patients without subclinical enthesopathy (P = 0.047). Patients with asymptomatic enthesopathy had significantly thicker proximal nail folds (1.44 ± 0.312 vs. 1.23 ± 0.27, P = 0.023). Nail beds and matrices were also thicker but the differences were not statistically significant (1.77 ± 0.27 vs. 1.74 ± 0.21, P = 0.66, and 1.79 ± 0.28 vs. 1.67 ± 0.19, P = 0.10, respectively). No statistically significant differences in the trilaminar structure were found between both groups. Patients with and without asymptomatic enthesopathy of extensor digitorum tendons did not statistically differ as regards ultrasonographic alterations of the Achilles tendons (60.6% vs. 46.4%, P 0.368). Conclusion: Enthesopathy abnormalities can be detected by US in patients with psoriasis without musculoskeletal complaints frequently. There is a close relationship between subclinical enthesopathy of the extensor digitorum tendon and the presence of nail alterations. Further studies are required to research what implications have the presence of these ungual alterations measured by US, and how it affects later development of a PsA. [ABSTRACT FROM AUTHOR]

The variability of seawater temperature through time is a critical measure of climate change, yet its reconstruction remains problematic in many regions. Mg/Ca and oxygen isotope (δ18OC) measurements in foraminiferal carbonate shells can be combined to reconstruct seawater temperature and δ18O (δ18OSW). The latter is a measure of changes in local hydrology (e.g., precipitation/evaporation, freshwater inputs) and global ice volume. But diagenetic processes may affect foraminiferal Mg/Ca. This restricts its potential in many places, including the Mediterranean Sea, a strategic region for deciphering global climate and sea-level changes. High alkalinity/salinity conditions especially bias Mg/Ca temperatures in the eastern Mediterranean (eMed). Here we advance the understanding of both western Mediterranean (wMed) and eMed hydrographic variability through the penultimate glacial termination (TII) and last interglacial, by applying the clumped isotope (Δ47) paleothermometer to planktic foraminifera with a novel data-processing approach. Results suggest that North Atlantic cooling during Heinrich stadial 11 (HS11) affected surface-water temperatures much more in the wMed (during winter/spring) than in the eMed (during summer). The method's paired Δ47 and δ18OC data also portray δ18OSW. These records reveal a clear HS11 freshwater signal, which attenuated toward the eMed, and also that last interglacial surface warming in the eMed was strongly amplified by water-column stratification during the deposition of the organic-rich (sapropel) interval known as S5. [ABSTRACT FROM AUTHOR]

Background Infantile hemangiomas with minimal or arrested growth ( IH- MAGs) are characterized by a proliferative component of <25% of its surface area. The co-occurrence of IH- MAGs and soft tissue anomalies is rare, and case series of this association are lacking. Objective We present 10 cases of IH- MAGs associated with soft tissue hypertrophy and describe their clinical features. Methods We reviewed all infantile hemangiomas with minimal or arrested growth seen between 2009 and 2016 in the dermatology clinic department at Hospital Santa Creu i Sant Pau, Barcelona. To collect more patients, we also requested cases from the Hemangioma Investigator Group and members of the Spanish Society of Vascular Anomalies. Results Ten patients had IH- MAGs associated with soft tissue hypertrophy; seven involving the arm and three involving the leg. All displayed a segmental pattern, a doughy and puffy texture and prominent surface veins. No significant asymmetries in limbs and no other visceral anomalies were observed at follow-up (range 15 months to 7 years). One patient reported coldness in the limb with infantile hemangioma, but RMI-angiography did not disclose a vascular malformation underneath the lesion. Ulceration was observed in three patients. The proliferative component in all IH- MAGs had faded at 1-year follow-up, while soft tissue hypertrophy and prominent vessels remained unchanged. Conclusions In this first case series of IH- MAGS associated with soft tissue hypertrophy, soft tissue hypertrophy was not progressive and remained unchanged over time, unlike the proliferative component of classic infantile hemangioma. The origin of the prominent vessels and the higher ulceration risk are unknown; however, these findings are probably related to a minor disruption of local vessels not detected in imaging tests. [ABSTRACT FROM AUTHOR]

This work focuses on the validation of a method for reconstructing the fcc crystallographic data from martensite orientation electron backscatter diffraction (EBSD) maps based on the ' γ nuclei identification' and ' γ nuclei spreading strategy.' To that end, an Fe-30Ni alloy was employed. The martensite transformation start temperature ( M ) of this material is close to or below room temperature; therefore, during hot deformation and after water quenching, it presents an fcc austenitic microstructure, while after subzero quenching, austenite-to-martensite transformation takes place. Accordingly, the reconstruction procedure can be applied to the martensitic EBSD crystallographic data, and the morphological and orientation results of the reconstruction can be validated by comparison with the original crystallographic fcc data. Torsion tests were performed to produce recrystallized and deformed austenite microstructures. Although applying the Kurdjumov-Sachs orientation relationship (OR) resulted in reconstructed area fractions larger than 75 pct, the reconstruction quality improved significantly when other ORs closer to the Greninger-Troiano OR were applied. The analysis carried out on the recrystallized microstructure shows that the method is robust against variation in the different parameters involved in the reconstruction. Good angular and morphological reconstruction results were obtained in both recrystallized and deformed microstructures, including the ability to reconstruct twins. [ABSTRACT FROM AUTHOR]

The aim of this work is to analyze the influence of the fast development of a disease on competition dynamics. To this end we present two discrete time ecoepidemic models. The first one corresponds to the case of one parasite affecting demography and intraspecific competition in a single host, whereas the second one contemplates the more complex case of competition between two different species, one of which is infected by the parasite. We carry out a complete mathematical analysis of the asymptotic behavior of the solutions of the corresponding systems of difference equations and derive interesting ecological information about the influence of a disease in competition dynamics. This includes an assessment of the impact of the disease on the equilibrium population of both species as well as some counterintuitive behaviors in which although we would expect the outbreak of the disease to negatively affect the infected species, the contrary happens. [ABSTRACT FROM AUTHOR]

In this work we present a discrete predator-prey ecoepidemic model. The predator-prey interactions are represented by a discrete Leslie-Gower model with prey intra-specific competition. The disease dynamics follows a discrete SIS epidemic model with frequency-dependent transmission. We focus on the case of disease only affecting prey though the case of a parasite of the predators is also presented. We assume that parasites provoke density- and trait-mediated indirect interactions in the predator-prey community that occur on a shorter time scale. This is included in the model considering that in each time unit there exist a number k of episodes of epidemic changes followed by a single episode of demographic change, all of them occurring separately. The aim of this work is examining the effects of parasites on the long-term prey-predators interactions. These interactions in the absence of disease are governed by the Leslie-Gower model. In the case of endemic disease they can be analyzed through a reduced predator-prey model which summarizes the disease dynamics in its parameters. Conditions for the disease to drive extinct the whole community are obtained. When the community keeps stabilized different cases of the influence of disease on populations sizes are presented. [ABSTRACT FROM AUTHOR]

In this work, we are interested in the implementation of single-qubit gates on coupled Bose-Einstein condensates (BECs). The system, a feasible candidate for a qubit, consists of condensed atoms in different hyperfine levels coupled by a two-photon transition. It is well established that the dynamics of coupled BECs can be described by the two-mode Hamiltonian that takes into account the confinement potential of the trap and the effects of collisions associated with each condensate. Other effects, such as collisions between atoms belonging to different BECs and detuning, are included in this approach. We demonstrate how to implement two types of quantum logic gates: population-transfer gates (NOT, $\hat {Y}$, and Hadamard), which require a population inversion between hyperfine levels, and phase gates ( $\hat {Z}$, $\hat {S}$, and $\hat {T}$), which require self-trapping. We also discuss the experimental feasibility by evaluating the robustness of quantum gates against variations of physical parameters outside of the ideal conditions for the implementation of each quantum logic gate. [ABSTRACT FROM AUTHOR]

This paper presents Analog Fault Tolerant University of Seville Debugging System (AFTU), a tool to evaluate the Single-Event Effect (SEE) sensitivity of analog/mixed signal microelectronic circuits at transistor level. As analog cells can behave in an unpredictable way when critical areas interact with the particle hitting, there is a need for designers to have a software tool that allows an automatic and exhaustive analysis of Single-Event Effects influence. AFTU takes the test-bench SPECTRE design, emulates radiation conditions and automatically evaluates vulnerabilities using user-defined heuristics. To illustrate the utility of the tool, the SEE sensitivity of a 13-bits Successive Approximation Analog-to-Digital Converter (ADC) has been analysed. This circuit was selected not only because it was designed for space applications, but also due to the fact that a manual SEE sensitivity analysis would be too time-consuming. After a user-defined test campaign, it was detected that some voltage transients were propagated to a node where a parasitic diode was activated, affecting the offset cancelation, and therefore the whole resolution of the ADC. A simple modification of the scheme solved the problem, as it was verified with another automatic SEE sensitivity analysis. [ABSTRACT FROM PUBLISHER]

Our current understanding of ocean-atmosphere-cryosphere interactions at ice-age terminations relies largely on assessments of the most recent (last) glacial-interglacial transition, Termination I (T-I). But the extent to which T-I is representative of previous terminations remains unclear. Testing the consistency of termination processes requires comparison of time series of critical climate parameters with detailed absolute and relative age control. However, such age control has been lacking for even the penultimate glacial termination (T-II), which culminated in a sea-level highstand during the last interglacial period that was several metres above present. Here we show that Heinrich Stadial 11 (HS11), a prominent North Atlantic cold episode, occurred between 135 ± 1 and 130 ± 2 thousand years ago and was linked with rapid sea-level rise during T-II. Our conclusions are based on new and existing data for T-II and the last interglacial that we collate onto a single, radiometrically constrained chronology. The HS11 cold episode punctuated T-II and coincided directly with a major deglacial meltwater pulse, which predominantly entered the North Atlantic Ocean and accounted for about 70 per cent of the glacial-interglacial sea-level rise. We conclude that, possibly in response to stronger insolation and CO2 forcing earlier in T-II, the relationship between climate and ice-volume changes differed fundamentally from that of T-I. In T-I, the major sea-level rise clearly post-dates Heinrich Stadial 1. We also find that HS11 coincided with sustained Antarctic warming, probably through a bipolar seesaw temperature response, and propose that this heat gain at high southern latitudes promoted Antarctic ice-sheet melting that fuelled the last interglacial sea-level peak. [ABSTRACT FROM AUTHOR]

Purpose. To study whether a corneal thickness segmentation model, consisting in a central circular zone of 1 mm radius centered at the corneal apex (zone I) and five concentric rings of 1 mm width (moving outwards: zones II to VI), could boost the diagnostic accuracy of Heidelberg Retina Tomograph’s (HRT’s) MRA and GPS. Material and Methods. Cross-sectional study. 121 healthy volunteers and 125 patients with primary open-angle glaucoma. Six binary multivariate logistic regression models were constructed (MOD-A1, MOD-A2, MOD-B1, MOD-B2, MOD-C1, and MOD-C2). The dependent variable was the presence of glaucoma. In MOD-A1, the predictor was the result (presence of glaucoma) of the analysis of the stereophotography of the optic nerve head (ONH). In MOD-B1 and MOD-C1, the predictor was the result of the MRA and GPS, respectively. In MOD-B2 and MOD-C2, the predictors were the same along with corneal variables: central, overall, and zones I to VI thicknesses. This scheme was reproduced for model MOD-A2 (stereophotography along with corneal variables). Models were compared using the area under the receiver operator characteristic curve (AUC). Results. MOD-A1-AUC: 0.771; MOD-A2-AUC: 0.88; MOD-B1-AUC: 0.736; MOD-B2-AUC: 0.845; MOD-C1-AUC: 0.712; MOD-C2-AUC: 0.838. Conclusion. Corneal thickness variables enhance ONH assessment and HRT’s MRA and GPS diagnostic capacity. [ABSTRACT FROM AUTHOR]

The presence of hypoxic regions in solid tumors is an adverse prognostic factor for patient outcome. Here, we show that hypoxia induces the expression of Ephrin-A3 through a novel hypoxia-inducible factor (HIF)-mediated mechanism. In response to hypoxia, the coding EFNA3 mRNA levels remained relatively stable, but HIFs drove the expression of previously unknown long noncoding (lnc) RNAs from EFNA3 locus and these lncRNA caused Ephrin-A3 protein accumulation. Ephrins are cell surface proteins that regulate diverse biological processes by modulating cellular adhesion and repulsion. Mounting evidence implicates deregulated ephrin function in multiple aspects of tumor biology. We demonstrate that sustained expression of both Ephrin-A3 and novel EFNA3 lncRNAs increased the metastatic potential of human breast cancer cells, possibly by increasing the ability of tumor cells to extravasate from the blood vessels into surrounding tissue. In agreement, we found a strong correlation between high EFNA3 expression and shorter metastasis-free survival in breast cancer patients. Taken together, our results suggest that hypoxia could contribute to metastatic spread of breast cancer via HIF-mediated induction of EFNA3 lncRNAs and subsequent Ephrin-A3 protein accumulation. [ABSTRACT FROM AUTHOR]

Purpose: To compare central corneal thickness (CCT) values obtained by Lenstar (LE), Pentacam (PC), specular microscopy (SM) and ultrasound pachymetry (UP) in healthy corneas and study their influence on intraocular pressure (IOP) readings determined by Goldmann applanation tonometry (GAT). Methods: CCT was measured in 76 healthy subjects by LE, PC, SM and UP. We established Lin's concordance correlation coefficient (ρ-C) between different techniques. The influence of CCT on GAT was established through univariate linear regression models, IOP being the dependent variable. Results: The highest ρ-C was found between LE and SM at 0.94 (95% CI: 0.91-0.96) and between LE and UP at 0.95 (95% CI: 0.94-0.97). IOP readings showed less variability when CCT was determined using LE (7.7%, B = 0.16; 95% CI: 0.004-0.28). Conclusions: Although CCT values obtained with UP, PC, SM and LE show good correlation, these methods are not completely interchangeable. The amount of IOP variation differs when CCT is determined using LE or SM. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objective: The main objective of this study was to not only determine the most appropriate sequence for the analysis of white matter hyperintensities (WMH) on MRI but also to confirm the advantage of three-dimensional (3D) acquisition, as it has been suggested in previous studies, and to test the convenience of using maximum intensity projection (MIP) algorithms on 3D-fluid-attenuated inversion-recovery (FLAIR) images for a quicker evaluation of brain MR studies. Methods: The number of WMH was compared in 40 patients and a control group of 10 volunteers using 4 different imaging modalities: two dimensional (2D)-FLAIR, 2D fast spin echo proton density (FSE PD), 3D-FLAIR and FLAIR MIP, Four experienced radiologists took part in the imaging analysis. All studies were performed on a 1.5-T whole-body MR unit. Results: A statistically significant difference between the number of lesions detected on 3D acquisitions (FLAIR CUBE' or FLAIR MIP sequences) compared with those on 2D-FLAIR or 2D FSE PD was demonstrated. There is no significant difference between 3D-FLAIR and FLAIR MIP, therefore both of them can be used with similar results. Conclusion: 3D-FLAIR sequences should replace conventional 2D-FLAIR and/or FSE PD sequences in the MR acquisition protocol when WMH are suspected. MIP reformat algorithms are less time consuming, therefore these can also be used to simplify the detection. Advances in knowledge: 3D sequences are superior for WMH depiction. Moreover, MIP algorithms allow easier analyses with similar results. [ABSTRACT FROM AUTHOR]

In this work we review the aggregation of variables method for discrete dynamical systems. These methods consist of describing the asymptotic behaviour of a complex system involving many coupled variables through the asymptotic behaviour of a reduced system formulated in terms of a few global variables. We consider population dynamics models including two processes acting at different time scales. Each process has associated a map describing its effect along its specific time unit. The discrete system encompassing both processes is expressed in the slow time scale composing the map associated to the slow one and the k-th iterate of the map associated to the fast one. In the linear case a result is stated showing the relationship between the corresponding asymptotic elements of both systems, initial and reduced. In the nonlinear case, the reduction result establishes the existence, stability and basins of attraction of steady states and periodic solutions of the original system with the help of the same elements of the corresponding reduced system. Several models looking over the main applications of the method to populations dynamics are collected to illustrate the general results. [ABSTRACT FROM AUTHOR]

Software development is mainly a social activity where teams of developers should work as a coordinated unit to fulfill the needs of customers. Studies have shown the importance of teamwork ability as the main skill for software professionals both in local settings and in global software development. Teamwork performance can be evaluated according to different approaches but we need deeper analysis within software teams of differences in individuals' performance related to culture, nationality or even gender. We applied a simple evaluation experience named teamwork benefits awareness (TBA) to groups of last-year students of computing degrees with experience as junior IT professionals during intensive multinational workshops based on international software projects. TBA allowed to measure individual and team performance during a requirements analysis session based on a real project. Results segmented by nationality and gender are presented and analysed in comparison with the data collected from computing professionals in local settings. In general, no significant differences have been found out although interesting relations are suggested with two Hofstede's country indicators. TBA is also perceived as a good technique for highlighting both teamwork benefits as well as the nature of real situations of software requirements analysis and orientation to customer needs. [ABSTRACT FROM AUTHOR]

As an alternative to recombinant protein administration, ex vivo gene-modified cells may provide a novel strategy for systemic delivery of therapeutic proteins. This approach has been used in preclinical and clinical studies of a plethora of pathological conditions, including anemia, hemophilia and cancer for the production of erythropoietin, coagulation factors, immunostimulatory cytokines, recombinant antibodies and angiogenesis inhibitors. Cell delivery vehicles may also be varied: autologous or allogeneic, precursor or terminally differentiated cells, with targeting properties or immobilized in immunoprotective devices. This field did not meet the expectation raised initially, mainly because of difficulties with obtaining therapeutic plasma levels and the short lifespan of producer cells that hampered clinical application. Different non-hematopoietic stem/progenitor cells have emerged as potential delivery vehicles, since they are easy to obtain, expand and transduce, and they exhibit prolonged lifespans (with mesenchymal stem cells probably being the most popular cell type, but not the only one). Special emphasis is placed on the different routes used to deliver these cellular vehicles and the controversies about their targeting abilities. [ABSTRACT FROM AUTHOR]

Recently, the field of multiple hypothesis testing has experienced a great expansion, basically because of the new methods developed in the field of genomics. These new methods allow scientists to simultaneously process thousands of hypothesis tests. The frequentist approach to this problem is made by using different testing error measures that allow to control the Type I error rate at a certain desired level. Alternatively, in this article, a Bayesian hierarchical model based on mixture distributions and an empirical Bayes approach are proposed in order to produce a list of rejected hypotheses that will be declared significant and interesting for a more detailed posterior analysis. In particular, we develop a straightforward implementation of a Gibbs sampling scheme where all the conditional posterior distributions are explicit. The results are compared with the frequentist False Discovery Rate (FDR) methodology. Simulation examples show that our model improves the FDR procedure in the sense that it diminishes the percentage of false negatives keeping an acceptable percentage of false positives. [ABSTRACT FROM AUTHOR]

Approximate aggregation techniques consist of introducing certain approximations that allow one to reduce a complex system involving many coupled variables obtaining a simpler ʽʽaggregated systemʼʼ governed by a few variables. Moreover, they give results that allow one to extract information about the complex original system in terms of the behavior of the reduced one. Often, the feature that allows one to carry out such a reduction is the presence of different time scales in the system under consideration. In this work we deal with aggregation techniques in stochastic discrete time models and their application to the study of multiregional models, i.e., of models for an age structured population distributed amongst different spatial patches and in which migration between the patches is usually fast with respect to the demography (reproduction-survival) in each patch. Stochasticity in population models can be of two kinds: environmental and demographic. We review the formulation and the main properties of the dynamics of the different models for populations evolving in discrete time and subjected to the effects of environmental and demographic stochasticity. Then we present different stochastic multiregional models with two time scales in which migration is fast with respect to demography and we review the main relationships between the dynamics of the original complex system and the aggregated simpler one. Finally, and within the context of models with environmental stochasticity in which the environmental variation is Markovian, we make use these techniques to analyze qualitatively the behavior of two multiregional models in which the original complex system is intractable. In particular we study conditions under which the population goes extinct or grows exponentially. [ABSTRACT FROM PUBLISHER]

The objective of this paper is to present a methodology to evaluate the status of the Air Traffic Management (ATM) system in terms of the relationship between the offered capacity and the traffic demand, identifying weakness areas and proposing solutions. The first part of the methodology relates to the characterization and evaluation of the current system, while the second part analyzes the system development limit. The following general criteria are established to define the methodological framework: use of Air Traffic Control (ATC) sectors as analysis unit, consideration of network effects, tactical focus, relative character of the analysis, objectivity and a high level assessment for assumptions on the human and Communications, Navigation and Surveillance (CNS) elements. The steps followed start with definition of indicators and metrics, like the nominal criticality or the nominal efficiency of a sector; scenario characterization; network effects analysis to study the relations among the constitutive elements of the ATC system; diagnostic by means of a "System Status Diagram"; analytical study of the ATC system development limit; and finally, formulation of conclusions and proposal for improvement. This methodology was employed by the Spanish Air Navigation Service Provider in the frame of the Spanish Airspace Capacity Sustainability Program, although it could be applied elsewhere. [ABSTRACT FROM AUTHOR]

Several works have shown the feasibility of engineering functional blood vessels in vivo using human endothelial cells (ECs). Going further, we explored the therapeutic potential of neovessels after gene-modifying the ECs for the secretion of a therapeutic protein. Given that these vessels are connected with the host vascular bed, we hypothesized that systemic release of the expressed protein is immediate. As a proof of principle, we used primary human ECs transduced with a lentiviral vector for the expression of a recombinant bispecific αCEA/αCD3 antibody. These ECs, along with mesenchymal stem cells as a source of mural cells, were embedded in Matrigel and subcutaneously implanted in nude mice. High antibody levels were detected in plasma for 1 month. Furthermore, the antibody exerted a therapeutic effect in mice bearing distant carcinoembryonic-antigen (CEA)-positive tumors after inoculation of human T cells. In summary, we show for the first time the therapeutic effect of a protein locally secreted by engineered human neovessels. [ABSTRACT FROM AUTHOR]

The difficulties of software quality evaluation found during our activity in different projects and publications led us to investigate a systematic method for building domain-oriented quality models based on a sound empirical basis. General quality models need to be adapted to specific types of software products to be effective. Related literature reveals that existing quality models tend to suffer from poor empirical support. To overcome this situation, a review of applicable existing standards and related literature has enabled the generation of a basis for software quality models which can be adapted to specific application domains. The process, called DUMOD (Domain-oriented qUality MOdels Development), includes the collection of experts' opinions and the application of multivariate analysis techniques in order to eliminate redundant information and construct a validated model, more efficient and reliable. In this study, the empirical method to devise quality models for specific application domains is presented, as well as its application to a case study for security software products empirically validated by extensive collection of data from IT professionals. [ABSTRACT FROM AUTHOR]

Continuous Descent Approach (CDA) procedures for aircraft coming to an airport have proved their potential for reducing noise impact on the airport environment. During a CDA procedure, the aircraft keeps a specific altitude until it reaches top of descent (TOD), where it adopts a configuration that allows for continuous descent, i.e. with no "step-down" effects, without changing its status during approach, changing the speed and path profiles according to aircraft performance. A major problem faced when these procedures are applied in real scenarios is how compatible they are with conventional or staggered procedures. This article uses the aircraft total energy model (TEM) for a mathematical approach of aircraft descent, which allows for establishing their vertical, speed and thrusting profiles for a CDA-flying aircraft with fuel consumption and aerodynamic drag information provided by the Base of Aircraft Data (BADA).The purpose here is to have a simple, open tool to analyse the descent profiles of different aircraft into airports. This would enable us to predict the path followed by an aircraft from its dynamic state at descent launch, considering idle thrust and constant vertical. On the basis of the mathematical model and the computer-based development of the vertical and speed profiles followed by aircrafts, this article defines procedures that can be applied in a congested airport - like Madrid Barajas - so that its impact on real operation can be analysed as it is made compatible with conventional procedures. [ABSTRACT FROM AUTHOR]

Contents The aim of this study was to evaluate how different protein profiles of seminal plasma (SP) fractions affect sperm functionality in vitro. Ejaculates from three boars were separated into six fractions. The fractions differed from each other in their sperm content, in their total SP protein content, and their spermadhesin PSP-I/PSP-II and heparin-binding protein (HBP) concentrations. Spermatozoa were mainly recovered in fraction 2 (sperm-rich fraction, >1800 × 106 spermatozoa/ml), whereas the pre-sperm fraction 1 and the post-sperm fractions 4–6 contained low numbers of spermatozoa (<500 × 106/ml). Except in fraction 2, the total SP protein concentration and the concentration of both, spermadhesin PSP-I/PSP-II and the HBPs increased with fraction order. Distinct time-dependent effects were observed on motility characteristics and membrane integrity of highly diluted boar spermatozoa upon incubation with a 10% dilution of the SP from each fraction. The highest sperm viability was recorded after exposure for 5 h to fraction 2, followed by fractions 1 and 3. The percentages of motile spermatozoa also differed significantly among fractions after 5 h of incubation. Spermatozoa incubated with SP of fractions 1–3 showed the highest percentage motility. We conclude that different SP fractions exert distinct effects on the functionality of highly diluted boar spermatozoa. Fractions 1–3 appear to promote sperm survival, whereas fractions 4–6 seem to be harmful for preserving the physiological functions of highly diluted boar spermatozoa. [ABSTRACT FROM AUTHOR]

The epithelial localization and expression of the spermadhesin PSP-I and PSP-II subunits were determined in the testis, ductus epididymes (caput, corpus and cauda), seminal vesicles and bulbourethral glands of mature boars, using immunohistochemical, western blotting and RT-PCR methods. Immunohistochemistry showed positive labelling for PSP-I and PSP-II antibodies in the epithelium of seminal vesicles in all males tested. Positive immunolabelling, but with variable intensity, was also present in the epididymal epithelium (caput, corpus and cauda), although varying largely among segments and boars. Immunoreactivity was nearly or completely absent in the seminiferous epithelium and the bulbourethral gland, although SDS-PAGE and western blotting revealed the presence of PSP-I and PSP-II immunoreactive bands in all the tissue extracts, including the testis and the bulbourethral gland. mRNA amplification by RT-PCR using primers specific for PSP-I and PSP-II showed a trend similar to that observed for western blotting, i.e. intensity variation between tissues (even between segments of the same epididymis) and among boars. Our results indicate that the seminal vesicles are the main source of PSP-I and PSP-II spermadhesins, although epididymal segments, testis and the bulbourethral gland also participate in the expression of both proteins. [ABSTRACT FROM AUTHOR]

The aim of this work is to present a general class of nonlinear discrete time models with two time scales whose dynamics is susceptible of being approached by means of a reduced system. The reduction process is included in the so-called approximate aggregation of variables methods which consist of describing the dynamics of a complex system involving many coupled variables through the dynamics of a reduced system formulated in terms of a few global variables. For the time unit of the discrete system we use that of the slow dynamics and assume that fast dynamics acts a large number of times during it. After introducing a general two-time scales nonlinear discrete model we present its reduced accompanying model and the relationships between them. The main result proves that certain asymptotic behaviours, hyperbolic asymptotically stable (A.S.) periodic solutions, to the aggregated system entail that to the original system. [ABSTRACT FROM AUTHOR]

Aims: To clone and characterize the gene coding for BGN16·3, a β-1,6-glucanase putatively implicated in mycoparasitism by Trichoderma harzianum, a biocontrol agent used against plant pathogenic fungi. Methods and Results: Using degenerate primed PCR and cDNA library screening, we have cloned the cDNA coding BGN16·3. bgn16·3 showed a significant sequence identity (50%) to bgn16·1; however, they both have low identity to the previously cloned bgn16·2, allowing the identification of amino acid sequences putatively involved in the common catalytic activity of the three proteins. bgn16·3 is a single-copy gene and highly homologous sequences are present in all tested Trichoderma species. bgn16·3 expression pattern is analysed by Northern blot, finding that it is expressed during the interaction of T. harzianum CECT 2413 with Botrytis cinerea, supporting the implication of the enzyme in the mycoparasitic process. Conclusions: The cloned bgn16·3 completes the knowledge on the β-1,6-glucanase isozyme system from T. harzianum CECT 2413. A highly homologous gene is present in all analysed Trichoderma strains. bgn16·3 is expressed under few specific conditions, including the mycoparasitic process. Significance and Impact of the Study: This study contributes to the knowledge of β-1,6-glucanases. It implicates this group of enzymes in the mycoparasitism by some biocontrol agents such as T. harzianum. [ABSTRACT FROM AUTHOR]

In this paper we propose a sliding mode control scheme that allows robust control of the output voltage in a class of non-linear switched converters that includes the non-inverting buck-boost, the Watkins-Johnson and the inverse of Watkins-Johnson. Using a full-state reference profile-based sliding surface, periodic signals may be tracked by the output voltage under appropriate restrictions. Furthermore, semi-infinite programming techniques are used to minimize power loses while taking into account the existence of load perturbations. The procedure consists of choosing a reference signal for the inductor current with minimum root mean square, subject to the maintenance of sliding regime under possible load variation in a set with known bounds. Realistic simulation results show a highly robust performance in the presence of load disturbances. [ABSTRACT FROM AUTHOR]

Infiltrating T lymphocytes are found in many malignancies, but they appear to be mostly anergic and do not attack the tumor, presumably because of defective T-cell activation events. Recently, we described a strategy for the tumor-specific polyclonal activation of tumor-resident T lymphocytes based on the in situ production of recombinant bispecific antibodies (bsAbs) by transfected nonhematological cell lines. Here, we have constructed a novel HIV-1-based lentiviral vector for efficient gene transduction into various human hematopoietic cell types. Several myelomonocytic and lymphocytic cell lines secreted the anti-carcinoembryonic antigen (CEA) × anti-CD3 diabody in a functionally active form with CD3+ T-cell lines being the most efficient secretors. Furthermore, primary human peripheral blood lymphocytes (PBLs) were also efficiently transduced and secreted high levels of functional diabody. Importantly gene-modified PBLs significantly reduced in vivo tumor growth rates in xenograft studies. These results demonstrate, for the first time, the utility of lentiviral vectors for sustained expression of recombinant bsAbs in human T lymphocytes. Such T lymphocytes, transduced ex vivo to secrete the activating diabody in autocrine fashion, may provide a promising route for a gene therapy strategy for solid human tumors.Cancer Gene Therapy (2007) 14, 380–388. doi:10.1038/sj.cgt.7701021; published online 12 January 2007 [ABSTRACT FROM AUTHOR]