Acoustic Phonon-Assisted Resonant Tunneling via Single Impurities

We perform the investigations of the resonant tunneling via impurities embedded in the AlAs barrier of a single GaAs/AlGaAs heterostructure. In the $I(V)$ characteristics measured at 30mK, the contribution of individual donors is resolved and the fingerprints of phonon assistance in the tunneling process are seen. The latter is confirmed by detailed analysis of the tunneling rates and the modeling of the resonant tunneling contribution to the current. Moreover, fluctuations of the local structure of the DOS (LDOS) and Fermi edge singularities are observed.Comment: accepted in Phys. Rev.

Etiology of ‘sinus headache’. Moving the focus from rhinology to neurology. A systematic review

‘Sinus headache and/or facial pain’ (SH) is a common complaint encountered by otorhi-nolaryngologists, neurologists and general practitioners. However, several studies suggested that the majority of those cases may be attributed to primary headaches (i.e., migraine and tension-type headache (TTH). The purpose of this review is to evaluate the etiology of SH. The first part in-cludes cross-sectional studies analyzing the prevalence of respective diagnoses in subjects with SH. The majority of these publications indicate that migraine and TTH are the most prevalent causes of SH, although most of these studies were conducted in a clinical setting. The second part of this review included treatment trials in subjects with SH. The findings from this part of the review show that SH without rhinosinusitis responds well to pharmacotherapy targeted at primary headaches. This observation further supports a neurologic etiology of the majority of SH cases

Hydrostatic pressure study of paramagnetic-ferromagnetic phase transition in (Ga,Mn)As

The effect of hydrostatic pressure on the paramagnetic - ferromagnetic phase transition has been studied in (Ga,Mn)As. The variation of the Curie temperature (TC) with pressure was monitored by two transport methods: (1) - measurement of zero field resistivity versus temperature {\rho}(T), (2) - dependence on temperature of the Hall voltage hysteresis loop. Two specimens of different resistivity characteristics were examined. The measured pressure-induced changes of TC were relatively small (of the order of 1K/GPa) for both samples, however they were opposite for the two.Comment: 8 pages, 7 figure

Coexistence of Anomalous Hall Effect and Weak Net Magnetization in Collinear Antiferromagnet MnTe

Anomalous Hall effect (AHE) plays important role in the rapidly developing field of antiferromagnetic spintronics. It has been recently discussed that it can be a feature of not only uncompensated magnetic systems but also in altermagnetic materials. Hexagonal MnTe belongs to this appealing group of compounds exhibiting AHE and is commonly perceived as magnetically compensated. Here, we demonstrate that bulk form of MnTe exhibits small but detectable magnetic moment correlating with hysteretic behaviour of the AHE. We formulate a phenomenological model which explains how this feature allows to create a disbalance between states with opposite N\'eel vector and prevent the AHE signal from averaging out to zero. Moreover, we show how the dependence of AHE on the N\'eel vector arises on microscopical level and highlight the differences in Berry curvature between magnetically compensated and uncompensated systems

Excellent Response to OnabotulinumtoxinA: Different Definitions, Different Predictors

The identification of patients who can benefit the most from the available preventive treatments is important in chronic migraine. We explored the rate of excellent responders to onabotulinumtoxinA in a multicenter European study and explored the predictors of such response, according to different definitions. A pooled analysis on chronic migraineurs treated with onabotulinumtoxinA and followed-up for, at least, 9 months was performed. Excellent responders were defined either as patients with a ≥75% decrease in monthly headache days (percent-based excellent responders) or as patients with <4 monthly headache days (frequency-based excellent responders). The characteristics of excellent responders at the baseline were compared with the ones of patients with a <30% decrease in monthly headache days. Percent-based excellent responders represented about 10% of the sample, whilst frequency-based excellent responders were about 5% of the sample. Compared with non-responders, percent-based excellent responders had a higher prevalence of medication overuse and a higher excellent response rate even after the 1st and the 2nd injection. Females were less like to be frequency-based excellent responders. Chronic migraine sufferers without medication overuse and of female sex may find fewer benefits with onabotulinumtoxinA. Additionally, the excellent response status is identifiable after the first cycle

Influence of the ERTMS/ETCS control system traffic on the increase in the capacity of railway lines

System ETCS został zaprojektowany do stosowania na wszystkich kategoriach infrastruktury obejmującej ruch pasażerskich i towarowych, odcinkach linii dużych prędkości, obsługę pociągu na liniach konwencjonalnych i regularnych, węzły, stacje rozrządowe. Warunkiem o wysokim priorytecie jest osiągnięcie przepustowości dla każdej aplikacji ETCS, stosowanej na liniach lub węzłach kolejowych. W celu oszacowania i spełnienia warunków pojemności linii należy rozważyć następujące parametry: cechy charakterystyczne infrastruktury, plany transportowe i poziom punktualności

ERTMS - perspectives for system

W obecnej chwili wspólne wysiłki kolei oraz przemysłu, wspierane przez Komisję Europejską i Europejską Agencją Kolejową (ERA), osiągają coraz lepsze wyniki w obszarze dostaw systemów sterowania ruchem ERTMS. Dotychczas, w pracy systemy ETCS i GSM-R były dominujące w eksploatacji miejscowej, jako tak zwane "wyspy". Deklarowane korzyści z systemu GSM-R, wynikają głównie i rozległego zasięgu stosowania ogólnych aplikacji GSM i od zdobytego doświadczenia z produkcji na szeroką skalę. Problemy wynikające z charakterystycznej specyfiki kolejowej zostały rozwiązane dla stref, tj. obszary robót i manewrowe, pokrycia radiowego tunelu i osiągnięcie niezmiernie wysokiej dokładności dla transmisji danych dla ETCS. Instalacja i eksploatacja GSM-R udowadnia realizację stawianych systemowi zadań i celów dla kolejowych rozwiązań technicznych, organizacyjnych i zarządzania

Basic Assumptions and Functions of the ETCS Simulator

W życiu codziennym ważną rolę odgrywają symulatory. Znalazły one także zastosowanie w kolejnictwie. W artykule zaprezentowano możliwości zastosowania symulatora ETCS na kolei.Simulators play important role in the everyday life. They have been applied in the railway engineering as well. The paper presents possibilities to use the ETCS simulator by the Railways

The Issues Related to Modernization of a Line with Low Density of Traffic

W artykule omówiono zagadnienia związane z modernizacją urządzeń sterowania ruchem kolejowym stosowanych na liniach kolejowych. Przeprowadzona analiza rynku linii o małym natężeniu ruchu wskazała korzyści wynikające z celowości realizacji inwestycji modernizacyjnych, a także przedstawiła obszary, w których jest możliwe poszukiwanie oszczędności wpływające na zbilansowanie inwestycji. W rozważaniach przedstawiono problemy związane z wyborem zakresu wykonywanych robót modernizacyjnych na liniach o małym natężeniu ruchu, a dla wybranych opcji przedstawiono analizę efektywności finansowej wybranych wariantów modernizacyjnych.The paper discusses issues concerning the modernization of safety installations applied in the railway lines. Low density of traffic line market analysis has shown benefits of modernization investments and indicated the areas where savings influencing investment balancing could be achieved. Next, the issues related to the choice of the scope of modernization work in the lines with low density of traffic were presented, while analysis of financial effectiveness was prepared for selected modernization variants