Bifurcations in the theory of current transfer to cathodes of dc discharges and observations of transitions between different modes

General scenarios of transitions between different spot patterns on electrodes of dc gas discharges and their relation to bifurcations of steady-state solutions are analyzed. In the case of cathodes of arc discharges, it is shown that any transition between different modes of current transfer is related to a bifurcation of steady-state solutions. In particular, transitions between diffuse and spot modes on axially symmetric cathodes, frequently observed in the experiment, represent an indication of the presence of pitchfork or fold bifurcations of steady-state solutions. Experimental observations of transitions on cathodes of dc glow microdischarges are analyzed and those potentially related to bifurcations of steady-state solutions are identified. The relevant bifurcations are investigated numerically and the computed patterns are found to conform to those observed in the course of the corresponding transitions in the experiment

Special subgroups of regular semigroups

This work was partially supported by the Portuguese Foundation for Science and Technology through the grant UID/MAT/00297/2013 (CMA).Extending the notions of inverse transversal and associate subgroup, we consider a regular semigroup S with the property that there exists a subsemigroup T which contains, for each x∈S, a unique y such that both xy and yx are idempotent. Such a subsemigroup is necessarily a group which we call a special subgroup. Here we investigate regular semigroups with this property. In particular, we determine when the subset of perfect elements is a subsemigroup and describe its structure in naturally arising situations.PostprintPeer reviewe

Congruences associated with inverse transversals

An inverse transversal of a regular semigroup $S$ is an inverse subsemigroup of $S$ that contains a unique inverse $x^\circ$ of every element $x$ of $S$. Here we consider the congruences on such a semigroup, considered as an algebra of type (2, 1). The structure of such semigroups being known, with 'building bricks' the inverse subsemigroup $S^\circ$ and the sub-bands $I = \{xx^\circ; x\in S\},\Lambda = \{x^\circ x; x\in S\}$, we investigate how congruences on $S$ are related to congruences on these building bricks

A Systemic Review of Endocardial Left Ventricular Pacing

Background: Endocardial left ventricular pacing is an alternative technique used in cardiac resynchronization therapy (CRT), when placement of a left ventricular lead is not possible via the coronary sinus or in non-responders to conventional CRT. Objectives: To review the evidence regarding the efficacy and safety of endocardial left ventricular pacing. Methods: Systematic research on Medline (PubMed), ClinicalTrials.gov and Embase with the terms "endocardial left ventricular pacing", "biventricular pacing" or "endocardial left pacing" was performed with the identification of 1038 results. Eleven studies with endocardial left ventricular pacing patients were included, independent of the technique being applied to naïve CRT patients or con non-responders to conventional CRT. The end-point of this analysis was the impact of endocardial left ventricular pacing techniques regarding New York Heart Association (NYHA) functional classification, left ventricular ejection fraction (LVEF) and QRS width, and the occurrence of complications Mean differences (MD) and confidence interval (CI) was used as a measurement of treatment. Results: A total of 560 patients were included, with different techniques used (trans-atrial septal technique, trans-ventricular septal technique and transapical technique). Significant improvement was registered in NYHA class (MD 0.73, CI 0.48-0.98, p<0.00001, I2 = 87%), LVEF (MD -7.63, CI -9.93 - -5.33, p<0.00001, I2 = 69%) and QRS width (MD 29.25, CI 9.99-48.50, p<0.00001, I2 = 91%). Several complications were reported after the procedure, 11 pocket infections, 22 transient ischemic attacks, 18 ischemic strokes, 41 thromboembolic events, among other complications. The mortality rate during the follow-up was 20.54%. Conclusion: Left ventricular endocardial pacing is a feasible alternative to conventional CRT, with clinical, electrocardiographic and echocardiogrphic improvement. However, first data regarding this procedure was associated with significant complications rates.info:eu-repo/semantics/publishedVersio

Influence of the external pressure on the quantum correlations of molecular magnets

The study of quantum correlations in solid state systems is a large avenue for research and their detection and manipulation are an actual challenge to overcome. In this context, we show by using first-principles calculations on the prototype material KNaCuSi$_{4}$O$_{10}$ that the degree of quantum correlations in this spin cluster system can be managed by external hydrostatic pressure. Our results open the doors for research in detection and manipulation of quantum correlations in magnetic systems with promising applications in quantum information science

Patterns of Mycobacterium tuberculosis-complex excretion and characterization of super-shedders in naturally-infected wild boar and red deer

Wild boar (Sus scrofa) and red deer (Cervus elaphus) are the main maintenance hosts for bovine tuberculosis (bTB) in continental Europe. Understanding Mycobacterium tuberculosis complex (MTC) excretion routes is crucial to define strategies to control bTB in free-ranging populations, nevertheless available information is scarce. Aiming at filling this gap, four different MTC excretion routes (oronasal, bronchial-alveolar, fecal and urinary) were investigated by molecular methods in naturally infected hunter-harvested wild boar and red deer. In addition MTC concentrations were estimated by the Most Probable Number method. MTC DNA was amplified in all types of excretion routes. MTC DNA was amplified in at least one excretion route from 83.0% (CI95 70.8-90.8) of wild ungulates with bTB-like lesions. Oronasal or bronchial-alveolar shedding were detected with higher frequency than fecal shedding (p 10(3) CFU/g or mL (referred here as super-shedders). Red deer have a significantly higher risk of being super-shedders compared to wild boar (OR = 11.8, CI95 2.3-60.2). The existence of super-shedders among the naturally infected population of wild boar and red deer is thus reported here for the first time and MTC DNA concentrations greater than the minimum infective doses were estimated in excretion samples from both species.We are grateful to all owners, hunters and hunting organizations that helped us to collect samples. Thanks are also due to Monica Cunha (INIAV, Portugal) for her advice during the setup of the laboratorial diagnosis techniques. Nuno Santos was supported by the Fundacao para a Ciencia e a Tecnologia (Ph.D. Grant SFRH/BD/69390/2010). This is also a contribution to MINECO Plan Nacional grant AGL2014-56305 and FEDER, and to the EU FP7 grant ANTIGONE # 278976

Aspirin desensitization in a woman with inherited thrombophilia and recurrent miscarriage.

Women with inherited thrombophilia and recurrent miscarriage might benefit from preconceptional antiagreggation with low-dose acetylsalicylic acid (ASA), but concerns about severe adverse reactions may prevent physicians from performing this treatment in patients with ASA hypersensitivity. We report the first known case of ASA desensitization in a 41-year-old woman with inherited thrombophilia, who had homozygosity (4G/4G polymorphism) of the plasminogen activator inhibitor-1 (PAI-1) gene and first trimester recurrent miscarriage, and had previously presented with anaphylaxis to ASA. Desensitization was completed despite one self-limited adverse reaction, and the patient has maintained a daily ASA intake of 100 mg with good tolerance