Variable Metric Random Pursuit

We consider unconstrained randomized optimization of smooth convex objective functions in the gradient-free setting. We analyze Random Pursuit (RP) algorithms with fixed (F-RP) and variable metric (V-RP). The algorithms only use zeroth-order information about the objective function and compute an approximate solution by repeated optimization over randomly chosen one-dimensional subspaces. The distribution of search directions is dictated by the chosen metric. Variable Metric RP uses novel variants of a randomized zeroth-order Hessian approximation scheme recently introduced by Leventhal and Lewis (D. Leventhal and A. S. Lewis., Optimization 60(3), 329--245, 2011). We here present (i) a refined analysis of the expected single step progress of RP algorithms and their global convergence on (strictly) convex functions and (ii) novel convergence bounds for V-RP on strongly convex functions. We also quantify how well the employed metric needs to match the local geometry of the function in order for the RP algorithms to converge with the best possible rate. Our theoretical results are accompanied by numerical experiments, comparing V-RP with the derivative-free schemes CMA-ES, Implicit Filtering, Nelder-Mead, NEWUOA, Pattern-Search and Nesterov's gradient-free algorithms.Comment: 42 pages, 6 figures, 15 tables, submitted to journal, Version 3: majorly revised second part, i.e. Section 5 and Appendi

Potreba za psihosocijalnom rehabilitacijom oboljelih od raka

In addition to the healing and alleviation of primary somatic cancer symptoms, the comprehensive psycho oncological treatment of cancer patients is an important and fundamental component of oncological rehabilitation in Germany. Rehabilitation treatment encompasses medical, physiotherapeutic, psychological, and creative therapeutic methods, as well as psycho-educational interventions within the framework of an individualized therapy plan. Psycho-oncological interventions within rehabilitation are governed less by individual therapeutic schools of thought, and more by a supportive, patient-centered approach that integrates various psychotherapeutic methods. Adapted methods and techniques from various psychotherapeutic approaches (behavioral therapy, psychoanalytical psychotherapies, systemic family therapy, or hypnotherapy) are currently used in the treatment of cancer patients. A total of N=116 patients of the Paracelsus Clinic am See in Bad Gandersheim were able to be included in the study. In summary, this study shows that about two thirds of the patients admitted to the oncological rehabilitation clinic exhibit middle to high degrees of distress in the areas of anxiety and/or depression. Moreover, it appears to be particularly important to assess not only the mental distress of cancer patients but also their degree of information with regard to psycho-oncological treatment when performing screening for psycho-oncological treatment outside of the rehabilitation clinic setting. Here it is particularly important to accommodate for a differing need for differing forms of treatment (need for counseling, care, or treatment).Sveobuhvatno psiho-onkološko liječenje bolesnika s rakom važan je prilog u liječenju i ublažavanju primarnih somatskih simptoma te temeljna komponenta onkološke rehabilitacije u Saveznoj Republici Njemačkoj. Ova vrsta rehabilitacije obuhvaća medicinske, fizioterapijske, psihološke te kreativno terapijske pristupe, ali i psihoedukacijske intervencije u okviru individualiziranih terapijskih programa. Psiho-onkološki rehabilitacijski postupci manje su određeni kognitivnim psihoterapijskim metodma, a više potpornim, pacijentu usmjerenim pristupima koji obuhvaćaju različite psihoterapijske tehnike. Prilagođene metode i tehnike iz različitih psihoterapijskih pristupa (bihevioralna terapija, psihoanalitička psihoterapija, sistemska obiteljska terapija ili hipnoterapija) predstavljaju suvremeni koncept u liječenju onkoloških bolesnika. Ova studija provedena je na uzorku od 116 pacijenata Paracelsus Clinic am See u Bad Gandersheimu. Rezultati studije pokazali su da dvije trećine pacijenata uključenih u onkološku rehabilitaciju pokazuje srednji do visok stupanj poremećaja u području anksioznosti i/ili depresije. Osim toga, osobito je važno da se u uvjetima definiranja psiho-onkološkog liječenja u izvankliničkim uvjetima ne procjenjuje samo vrsta i stupanj psihičkog poremećaja, već također i razina informiranosti o psiho-onkološkom liječenju. U tom smislu posebno je važno različite oblike liječenja prilagoditi različitim osobnim potrebamabolesnika (npr. potreba za savjetovanjem, njegom, liječenjem)

Potreba za psihosocijalnom rehabilitacijom oboljelih od raka

In addition to the healing and alleviation of primary somatic cancer symptoms, the comprehensive psycho oncological treatment of cancer patients is an important and fundamental component of oncological rehabilitation in Germany. Rehabilitation treatment encompasses medical, physiotherapeutic, psychological, and creative therapeutic methods, as well as psycho-educational interventions within the framework of an individualized therapy plan. Psycho-oncological interventions within rehabilitation are governed less by individual therapeutic schools of thought, and more by a supportive, patient-centered approach that integrates various psychotherapeutic methods. Adapted methods and techniques from various psychotherapeutic approaches (behavioral therapy, psychoanalytical psychotherapies, systemic family therapy, or hypnotherapy) are currently used in the treatment of cancer patients. A total of N=116 patients of the Paracelsus Clinic am See in Bad Gandersheim were able to be included in the study. In summary, this study shows that about two thirds of the patients admitted to the oncological rehabilitation clinic exhibit middle to high degrees of distress in the areas of anxiety and/or depression. Moreover, it appears to be particularly important to assess not only the mental distress of cancer patients but also their degree of information with regard to psycho-oncological treatment when performing screening for psycho-oncological treatment outside of the rehabilitation clinic setting. Here it is particularly important to accommodate for a differing need for differing forms of treatment (need for counseling, care, or treatment).Sveobuhvatno psiho-onkološko liječenje bolesnika s rakom važan je prilog u liječenju i ublažavanju primarnih somatskih simptoma te temeljna komponenta onkološke rehabilitacije u Saveznoj Republici Njemačkoj. Ova vrsta rehabilitacije obuhvaća medicinske, fizioterapijske, psihološke te kreativno terapijske pristupe, ali i psihoedukacijske intervencije u okviru individualiziranih terapijskih programa. Psiho-onkološki rehabilitacijski postupci manje su određeni kognitivnim psihoterapijskim metodma, a više potpornim, pacijentu usmjerenim pristupima koji obuhvaćaju različite psihoterapijske tehnike. Prilagođene metode i tehnike iz različitih psihoterapijskih pristupa (bihevioralna terapija, psihoanalitička psihoterapija, sistemska obiteljska terapija ili hipnoterapija) predstavljaju suvremeni koncept u liječenju onkoloških bolesnika. Ova studija provedena je na uzorku od 116 pacijenata Paracelsus Clinic am See u Bad Gandersheimu. Rezultati studije pokazali su da dvije trećine pacijenata uključenih u onkološku rehabilitaciju pokazuje srednji do visok stupanj poremećaja u području anksioznosti i/ili depresije. Osim toga, osobito je važno da se u uvjetima definiranja psiho-onkološkog liječenja u izvankliničkim uvjetima ne procjenjuje samo vrsta i stupanj psihičkog poremećaja, već također i razina informiranosti o psiho-onkološkom liječenju. U tom smislu posebno je važno različite oblike liječenja prilagoditi različitim osobnim potrebamabolesnika (npr. potreba za savjetovanjem, njegom, liječenjem)

Continuous integral kernels for unbounded Schroedinger semigroups and their spectral projections

By suitably extending a Feynman-Kac formula of Simon [Canadian Math. Soc. Conf. Proc, 28 (2000), 317-321], we study one-parameter semigroups generated by (the negative of) rather general Schroedinger operators, which may be unbounded from below and include a magnetic vector potential. In particular, a common domain of essential self-adjointness for such a semigroup is specified. Moreover, each member of the semigroup is proven to be a maximal Carleman operator with a continuous integral kernel given by a Brownian-bridge expectation. The results are used to show that the spectral projections of the generating Schroedinger operator also act as Carleman operators with continuous integral kernels. Applications to Schroedinger operators with rather general random scalar potentials include a rigorous justification of an integral-kernel representation of their integrated density of states - a relation frequently used in the physics literature on disordered solids.Comment: 41 pages. Final version. Dedicated to Volker Enss on the occasion of his 60th birthda

Molecular epidemiology and antimicrobial resistance of Clostridioides difficile detected in chicken, soil and human samples from Zimbabwe

Background: Clostridioides difficile is the major cause of infectious nosocomial diarrhoea in industrialized nations. Data on the occurrence of C. difficile in Africa, ribotype (RT) distribution, antimicrobial susceptibility patterns and potential zoonotic transmission are scarce. Methods: 80 Zimbabwean C. difficile isolates from different sources (chicken [n = 30], soil [n = 21] and humans [n = 29]) were investigated using ribotyping, toxin gene detection, resistance testing, multiple-locus variable-number tandem repeat analysis (MLVA), and whole genome sequencing (WGS). Results: Among chicken isolates, the most common RTs were RT103 (6/30), RT025 (5/30) and RT070 (4/30). Within soil samples, RT025 and RT056 were most common (3/21 each). In contrast, the non-toxigenic RT084 was most frequently found in human isolates (4/29). Toxin genes were detected in only 19/29 human isolates. Susceptibility testing showed no resistance against metronidazole and vancomycin, and resistance against macrolides and rifampicin was scarce (3/80 and 2/80, respectively); however, 26/80 isolates showed moxifloxacin resistance. MLVA and WGS of strains with identical RTs stemming from different sources revealed clustering of RT025 and RT084 isolates from human und non-human samples. Conclusion: No "hypervirulent” strains were found. The detected clusters between human, chicken and soil isolates indicate ongoing transmission between humans and environmental sources and might point towards a zoonotic potential

Markov Random Field Segmentation of Brain MR Images

We describe a fully-automatic 3D-segmentation technique for brain MR images. Using Markov random fields the segmentation algorithm captures three important MR features, i.e. non-parametric distributions of tissue intensities, neighborhood correlations and signal inhomogeneities. Detailed simulations and real MR images demonstrate the performance of the segmentation algorithm. The impact of noise, inhomogeneity, smoothing and structure thickness is analyzed quantitatively. Even single echo MR images are well classified into gray matter, white matter, cerebrospinal fluid, scalp-bone and background. A simulated annealing and an iterated conditional modes implementation are presented. Keywords: Magnetic Resonance Imaging, Segmentation, Markov Random FieldsComment: 34 pages, 10 figures; the paper (published in 1997) has introduced the concept of Markov random field to the segmentation of medical MR images. For the published version see http://dx.doi.org/10.1109/42.65088

Identification of an ADAMTS2 frameshift variant in a cat family with Ehlers-Danlos syndrome.

We investigated four European domestic shorthair kittens with skin lesions consistent with the dermatosparaxis type of the Ehlers-Danlos syndrome (EDS), a connective tissue disorder. The kittens were sired by the same tomcat, but were born by three different mothers. The kittens had easily torn skin resulting in non-healing skin wounds. Both clinically and histologically, the skin showed thin epidermis in addition to inflammatory changes. Changes in collagen fibers were visible in electron micrographs. The complete genome of an affected kitten was sequenced. A one base pair duplication leading to a frameshift in the candidate gene ADAMTS2 was identified, p.(Ser235fs*3). All four affected cats carried the frameshift duplication in a homozygous state. Genotypes at this variant showed perfect co-segregation with the autosomal recessive EDS phenotype in the available family. The mutant allele did not occur in 48 unrelated control cats. ADAMTS2 loss-of-function variants cause autosomal recessive forms of EDS in humans, mice, dogs, cattle and sheep. The available evidence from our investigation together with the functional knowledge on ADAMTS2 in other species allow to classify the identified ADAMTS2 variant as pathogenic and most likely causative variant for the observed EDS

Discrimination between hypervirulent and non-hypervirulent ribotypes of Clostridioides difficile by MALDI-TOF mass spectrometry and machine learning

Hypervirulent ribotypes (HVRTs) of Clostridioides difcile such as ribotype (RT) 027 are epidemiologically important. This study evaluated whether MALDI-TOF can distinguish between strains of HVRTs and non-HVRTs commonly found in Europe. Obtained spectra of clinical C. difcile isolates (training set, 157 isolates) covering epidemiologically relevant HVRTs and non-HVRTs found in Europe were used as an input for diferent machine learning (ML) models. Another 83 isolates were used as a validation set. Direct comparison of MALDI-TOF spectra obtained from HVRTs and non-HVRTs did not allow to discriminate between these two groups, while using these spectra with certain ML models could diferentiate HVRTs from non-HVRTs with an accuracy >95% and allowed for a sub-clustering of three HVRT subgroups (RT027/ RT176, RT023, RT045/078/126/127). MALDI-TOF combined with ML represents a reliable tool for rapid identifcation of major European HVRTs

Ein-/Ausstieg in einen PKW – Besteht Unterstützungsbedarf bei älteren Menschen?

Im Alter vermehrt auftretende körperliche Beschwerden und Bewegungseinschränkungen erschweren den Ein-/Ausstieg in den PKW. Das Ziel der vorgestellten Probandenstudie ist es, die mit dem Ein-/ Ausstieg verbundene Beanspruchung zu analysieren und mithilfe einer optimal positionierten Einstiegshilfe zu minimieren. Hierzu wird zunächst die Ein-/Ausstiegsstrategie sowie die wirkende Beanspruchung ohne Einstiegshilfe näher analysiert. Anschließend wird die Einstiegshilfe in drei Positionen im Hinblick auf ihre beanspruchungsreduzierende Wirkung evaluiert