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A model for the evolution of laminates in finite-strain elastoplasticity
We study the time evolution in elastoplasticity within the rate-independent framework of generalized standard materials. Our particular interest is the formation and the evolution of microstructure. Providing models where existence proofs are possible is a challenging task since the presence of microstructure comes along with a lack of convexity and, hence, compactness arguments cannot be applied to prove the existence of solutions. In order to overcome this problem, we will incorporate information on the microstructure into the internal variable, which is still compatible with generalized standard materials. More precisely, we shall allow for such microstructure that is given by simple or sequential laminates. We will consider a model for the evolution of these laminates and we will prove a theorem on the existence of solutions to any finite sequence of time-incremental minimization problems. In order to illustrate the mechanical consequences of the theory developed some numerical results, especially dealing with the rotation of laminates, are presented
Quantum criticality and the phase diagram of the cuprates
I discuss a proposed phase diagram of the cuprate superconductors as a
function of temperature, carrier concentration, and a strong magnetic field
perpendicular to the layers. I show how the phase diagram gives a unified
interpretation of a number of recent experiments.Comment: 2 pages, 1 figure; Talk at M2S IX, Tokyo; (v2) corrected typo
Quantum critical point for stripe order: An organizing principle of cuprate superconductivity
A spin density-wave quantum critical point (QCP) is the central organizing
principle of organic, iron-pnictide, heavy-fermion and electron-doped cuprate
superconductors. It accounts for the superconducting Tc dome, the
non-Fermi-liquid resistivity, and the Fermi-surface reconstruction. Outside the
magnetically ordered phase above the QCP, scattering and pairing decrease in
parallel as the system moves away from the QCP. Here we argue that a similar
scenario, based on a stripe-order QCP, is a central organizing principle of
hole-doped cuprate superconductors. Key properties of Eu-LSCO, Nd-LSCO and YBCO
are naturally unified, including stripe order itself, its QCP, Fermi-surface
reconstruction, the linear-T resistivity, and the nematic character of the
pseudogap phase.Comment: Written for a special issue of Physica C on "Stripes and electronic
liquid crystal
Stripes and electronic quasiparticles in the pseudogap state of cuprate superconductors
This article is devoted to a discussion of stripe and electron-nematic order
and their connection to electronic properties in the pseudogap regime of
copper-oxide superconductors. We review basic properties of these
symmetry-breaking ordering phenomena as well as proposals which connect them to
quantum-oscillation measurements. Experimental data indicate that these orders
are unlikely to be the cause of the pseudogap phenomenon, implying that they
occur on top of the pseudogap state which itself is of different origin.
Specifically, we discuss the idea that the non-superconducting pseudogap ground
state hosts electron-like quasiparticles which coexist with a spin liquid,
realizing a variant of a fractionalized Fermi liquid. We speculate on how
stripe order in such a pseudogap state might offer a consistent description of
ARPES, NMR, quantum-oscillation, and transport data.Comment: 15 pages, 6 figs. Article prepared for a Physica C special issue on
"Stripes and Electronic Liquid Crystals
The CANNA-TICS Study Protocol: A Randomized Multi-Center Double-Blind Placebo Controlled Trial to Demonstrate the Efficacy and Safety of Nabiximols in the Treatment of Adults With Chronic Tic Disorders
Background: Gilles de la Tourette syndrome (TS) is a chronic neuropsychiatric disorder characterized by motor and vocal tics. First-line treatments for tics are antipsychotics and tic-specific behavioral therapies. However, due to a lack of trained therapists and adverse events of antipsychotic medication many patients seek alternative treatment options including cannabis. Based on the favorable results obtained from case studies on different cannabis-based medicines as well as two small randomized controlled trials using delta-9-tetrahydrocannabinol (THC), we hypothesize that the cannabis extract nabiximols can be regarded as a promising new and safe treatment strategy in TS.
Objective: To test in a double blind randomized clinical trial, whether treatment with the cannabis extract nabiximols is superior to placebo in patients with chronic tic disorders.
Patients and Methods: This is a multicenter, randomized, double-blind, placebo controlled, parallel-group, phase IIIb trial, which aims to enroll 96 adult patients with chronic tic disorders (TS or chronic motor tic disorder) across 6 centers throughout Germany. Patients will be randomized with a 2:1 ratio into a nabiximols and a placebo arm. The primary efficacy endpoint is defined as tic reduction of at least 30% (compared to baseline) according to the Total Tic Score of the Yale Global Tic Severity Scale (YGTSS-TTS) after 13 weeks of treatment. In addition, several secondary endpoints will be assessed including changes in different psychiatric comorbidities, quality of life, driving ability, and safety assessments.
Discussion: This will be the first large, controlled study investigating efficacy and safety of a cannabis-based medicine in patients with TS. Based on available data using different cannabis-based medicines, we expect not only a reduction of tics, but also an improvement of psychiatric comorbidities. If the cannabis extract nabiximols is proven to be safe and effective, it will be a valuable alternative treatment option. The results of this study will be of high health-economic relevance, because a substantial number of patients uses cannabis (illegally) as self-medication.
Conclusion: The CANNA-TICS trial will clarify whether nabiximols is efficacious and safe in the treatment of patients with chronic tic disorders
Seasonal variations in the diagnosis of testicular germ cell tumors: a national cancer registry study in austria
SIMPLE SUMMARY: Seasonal variations in cancer diagnosis could already be demonstrated in prostate and breast cancer. The reasons for this observed seasonal pattern are still unclear. The health care system or other determinants such as the protective function of vitamin D3 in carcinogenesis could be assumed as one explanation. Testicular germ cell tumors are the most common developed malignancy among young men. The aim of our study was to investigate, for the first time, the seasonal variations in the clinical diagnosis of testicular germ cell tumors. We have been able to confirm that the frequency of monthly newly diagnosed cases of testicular cell tumors in Austria has a strong seasonality, with a significant reduction in the tumor incidence during the summer months and an increase during the winter months. ABSTRACT: We conducted a retrospective National Cancer Registry study in Austria to assess a possible seasonal variation in the clinical diagnosis of testicular germ cell tumors (TGCT). In total, 3615 testicular cancer diagnoses were identified during an 11-year period from 2008 to 2018. Rate ratios for the monthly number of TGCT diagnoses, as well as of seasons and half-years, were assessed using a quasi-Poisson model. We identified, for the first time, a statistically significant seasonal trend (p < 0.001) in the frequency of monthly newly diagnosed cases of TGCT. In detail, clear seasonal variations with a reduction in the tumor incidence during the summer months (Apr–Sep) and an increase during the winter months (Oct–Mar) were observed (p < 0.001). Focusing on seasonality, the incidence during the months of Oct–Dec (p = 0.008) and Jan–Mar (p < 0.001) was significantly higher compared to the months of Jul–Sep, respectively. Regarding histopathological features, there is a predominating incidence in the winter months compared to summer months, mainly concerning pure seminomas (p < 0.001), but not the non-seminoma or mixed TGCT groups. In conclusion, the incidence of TGCT diagnoses in Austria has a strong seasonal pattern, with the highest rate during the winter months. These findings may be explained by a delay of self-referral during the summer months. However, the hypothetical influence of vitamin D3 in testicular carcinogenesis underlying seasonal changes in TGCT diagnosis should be the focus of further research
Transport Properties of Stripe-Ordered High Tc Cuprates
Transport measurements provide important characterizations of the nature of
stripe order in the cuprates. Initial studies of systems such as
La(1.6-x)Nd(0.4)Sr(x)CuO(4) demonstrated the strong anisotropy between in-plane
and c-axis resistivities, but also suggested that stripe order results in a
tendency towards insulating behavior within the planes at low temperature. More
recent work on La(2-x)Ba(x)CuO(4) with x=1/8 has revealed the occurrence of
quasi-two-dimensional superconductivity that onsets with spin-stripe order. The
suppression of three-dimensional superconductivity indicates a frustration of
the interlayer Josephson coupling, motivating a proposal that superconductivity
and stripe order are intertwined in a pair-density-wave state. Complementary
characterizations of the low-energy states near the Fermi level are provided by
measurements of the Hall and Nernst effects, each revealing intriguing
signatures of stripe correlations and ordering. We review and discuss this
work.Comment: 12 pages, 13 figures, brief revie
Clinical Efficacy of a Novel Therapeutic Principle, Anakoinosis
Classic tumor therapy, consisting of cytotoxic agents and/or targeted therapy, has not overcome therapeutic limitations like poor risk genetic parameters, genetic heterogeneity at different metastatic sites or the problem of undruggable targets. Here we summarize data and trials principally following a completely different treatment concept tackling systems biologic processes: the principle of communicative reprogramming of tumor tissues, i.e., anakoinosis(ancient greek for communication), aims at establishing novel communicative behavior of tumor tissue, the hosting organ and organism via re-modeling gene expression, thus recovering differentiation, and apoptosis competence leading to cancer control – in contrast to an immediate, “poisoning” with maximal tolerable doses of targeted or cytotoxic therapies. Therefore, we introduce the term “Master modulators” for drugs or drug combinations promoting evolutionary processes or regulating homeostatic pathways. These “master modulators” comprise a broad diversity of drugs, characterized by the capacity for reprogramming tumor tissues, i.e., transcriptional modulators, metronomic low-dose chemotherapy, epigenetically modifying agents, protein binding pro-anakoinotic drugs, such as COX-2 inhibitors, IMiDs etc., or for example differentiation inducing therapies. Data on 97 anakoinosis inducing schedules indicate a favorable toxicity profile: The combined administration of master modulators, frequently (with poor or no monoactivity) may even induce continuous complete remission in refractory metastatic neoplasia, irrespectively of the tumor type. That means recessive components of the tumor, successively developing during tumor ontogenesis, are accessible by regulatory active drug combinations in a therapeutically meaningful way. Drug selection is now dependent on situative systems characteristics, to less extent histology dependent. To sum up, anakoinosis represents a new substantive therapy principle besides novel targeted therapies
Antiferromagnetism and Superconductivity in Cerium based Heavy Fermion Compounds
The study of competing ground states is a central issue in condensed matter
physic. In this article we will discuss the interplay of antiferromagnetic
order and unconventional superconductivity in Ce based heavy-fermion compounds.
In all discussed examples superconductivity appears at the border of magnetic
order. Special focus is given on the pressure-temperature-magnetic field phase
diagram of CeRhIn5 and CeCoIn5 which allows to discuss microscopic coexistence
of magnetic order and superconductivity in detail. A striking point is the
similarity of the phase diagram of different classes of strongly correlated
systems which is discussed briefly. The recently discovered non-centrosymmetric
superconductors will open a new access with the possible mixing of odd and even
parity pairing.Comment: 38 pages, 22 figures, to be published in Comptes rendues - Physiqu
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