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The low-temperature linear and nonlinear transport on nanoperforated titanium nitride films is experimentally studied. A metallic Bose state is shown to appear in the system, and it transforms into a metallic state in a magnetic field. The linear and differential magnetoresistances of the system exhibit oscillations. A vortex Mott insulator was shown to transfer into a metallic state when a direct current passes through a film. [ABSTRACT FROM AUTHOR]

We investigate the evolution of the electronic transport in disordered NbTiN films at the insulating side of the superconductor-insulator transition as function of the effective system size along the current direction. We demonstrate that both, the threshold voltage characterizing low-temperature superinsulating phase, and the Berezinskii-Kosterlitz-Thouless criticality of the conductance above the superinsulator critical temperature, vanish upon increasing disorder taking the system far from the disorder-driven superconductor-insulator transition. We find that decrease in the system's effective size suppresses its insulating and superinsulating properties and that threshold voltage drops linearly with the diminishing system size. We demonstrate that this linear dependence can be used for experimental measurement of the linear tension of the electric string binding Cooper pairs and anti-Cooper pairs in a superinsulator. [ABSTRACT FROM AUTHOR]

Experimental results indicating a direct disorder-induced superconductor–insulator transition in NbTiN thin films have been reported. It has been shown that an increase in the resistance per square in the normal state is accompanied by the suppression of the critical temperature of the superconducting transition according to the fermion mechanism of suppression of superconductivity by disorder. At the same time, the temperature of the Berezinskii–Kosterlitz–Thouless transition is completely suppressed at a nonzero critical temperature and, then, the ground state changes to insulating, which is characteristic of the boson model of suppression of superconductivity by disorder. It has been shown that the temperature dependences of the resistance of insulating films follow the Arrhenius activation law. [ABSTRACT FROM AUTHOR]

The low-temperature transport properties of titanium nitride wires with the width comparable with or much larger than the superconducting coherence length are studied experimentally. It is shown that the reduction of the width of wires does not affect the transport properties at the temperatures above the superconducting transition temperature and electron transport in this temperature range is determined by quantum contributions to the conductivity from weak localization and electron-electron interaction. It is established that the reduction of the width of wires does not change the superconducting transition temperature but completely suppresses the topological Berezinskii-Kosterlitz-Thouless transition. It is found that the threshold magnetic field increases with a decrease in the width of wires. [ABSTRACT FROM AUTHOR]

The linear and nonlinear conductions of titanium nitride films with the thickness d ≤ 10 nm have been studied experimentally in the region of superconducting transitions. It has been shown that the inclusion of all quantum contributions to the conductivity at temperatures above the critical temperature of the superconducting transition T makes it possible to completely describe the temperature dependence of the conductivity measured in the linear regime, and the nonlinear behavior of the current-voltage characteristics is in complete agreement with the classical model of the heating of an electron gas in metals. The electron-phonon coupling constant has been determined. The analysis of the linear and nonlinear conductivities at temperatures below T shows that the transition to a superconducting state occurs through the Berezinskii-Kosterlitz-Thouless mechanism. [ABSTRACT FROM AUTHOR]

Vitiligo is an acquired pigmentary disorder characterized by depigmented macules and patches secondary to the loss of functional melanocytes. It is a chronic disease that affects between 0.1% and 2% of the general population, affecting both sexes and all races. The appearance and the unpredictable course are psychologically and socially devastating. The success of current therapeutic options is limited. The objective of this review was to assess non-surgical treatments of vitiligo and to determine if comparing these studies can lead to (1) practical applications in the clinical setting and (2) recommendations for future research including study design and topics to be investigated further. Combination therapies were found to be more effective than monotherapy, and most combinations included a form of phototherapy, of which narrow-band-UVB was found to be most effective with the least adverse effects. Topical treatment with corticosteroids, immunomodulators, vitamin D analogs, and psoralens had mixed outcomes. Oral therapies including antioxidants were helpful adjuvants to treatment. Studies lacked consistent design, mechanism of disease assessment, and long-term follow-up. Sample size was also frequently limited. This review found that while several non-surgical therapies exist for the treatment of vitiligo, their usefulness, especially in the long term, is not well understood. Those studies that were able to elicit repigmentation often lacked an assessment on quality of life and/or patjent satisfaction. More standardized methods of study design and assessment are needed to compare outcomes and make definitive conclusions on treatment effectiveness. [ABSTRACT FROM AUTHOR]

The nature of hadrons is one of the most fundamental mysteries of physics. It is generally agreed that they are made of "colored" quarks, which move nearly free at short scales but are confined inside hadrons by strong interactions at large distances. Because of confinement, quarks are never directly observable and, experimentally, their properties can be tested only indirectly, via high energy collisions. Here we show that superinsulating films realize a complete, one-color model system of hadron physics with Cooper pairs playing the role of quarks. We report measurements on highly controlled NbTiN films that provide a window into the interior of "Cooper pair mesons" and present the first direct evidence of asymptotic freedom, 't Hooft's dual superconductivity confinement mechanism, and magnetic monopoles. Quarks in the interior of hadrons make up most of ordinary matter, yet their observation is not possible, and their properties can only be probed indirectly. Adopting an analogy between physics of superinsulators and high energy physics, the authors present direct observations of the interior of electric mesons made of Cooper pairs by standard transport measurements. [ABSTRACT FROM AUTHOR]

We investigate the low-temperature complex impedance of disordered insulating thin TiN and NbTiN films in the frequency region 400 Hz–1 MHz in close proximity to the superconductor–insulator transition (SIT). The frequency, temperature, and magnetic field dependencies of the real and imaginary parts of the impedance indicate that in full accord with the theoretical predictions and earlier observations, the films acquire self-induced electronic granularity and become effectively random arrays of superconducting granules coupled via Josephson links. Accordingly, the inductive component of the response is due to superconducting droplets, while the capacitive component results from the effective Josephson junctions capacitances. The impedance crosses over from capacitive to inductive behavior as films go across the transition. [ABSTRACT FROM AUTHOR]

We discuss a challenging case of a 58-year-old Vietnamese-American woman who presented to her new primary care provider with an 8-year history of slowly progressive dysphagia, hoarseness, muscle weakness with associated frequent falls, and weight loss. She eventually reported dry eyes and dry mouth, and she was diagnosed with Sjogren's syndrome. Subsequently, she was additionally diagnosed with inclusion body myositis and gastric light-chain (AL) amyloidosis. Although inclusion body myositis has been previously associated with Sjogren's syndrome, inclusion body myositis is rare in non-Caucasians, and the trio of Sjogren's syndrome, inclusion body myositis, and AL amyloidosis has not been previously reported. Sjogren's syndrome is a systemic autoimmune condition characterized by ocular and oral dryness. It is one of the most common rheumatologic disorders in the USA and worldwide. Early diagnosis of Sjogren's is particularly important given the frequency and variety of associated autoimmune diseases and extraglandular manifestations. Furthermore, although inclusion body myositis has a low prevalence, it is the most common inflammatory myopathy in older adults and is unfortunately associated with long delays in diagnosis, so knowledge of this disorder is also crucial for practicing internists. [ABSTRACT FROM AUTHOR]

Dermatomyositis is a chronic systemic autoimmune disease characterized by inflammatory infiltrates in the skin and muscle. The wide variability in clinical and serologic presentation poses a diagnostic challenge for the internist. Appreciation of the clinical variants of dermatomyositis allows for expedient diagnosis and avoidance of diagnostic error. We illustrate these challenges with the case of a 51-year-old Vietnamese-American man who initially presented with fever of unknown origin in the absence of overt skin and muscle manifestations. The diagnosis of dermatomyositis was not evident on several clinical encounters due to the absence of these hallmark symptoms. We review the variable clinical manifestations of a subtype of dermatomyositis associated with an autoantibody against melanoma differentiation-associated protein 5 (anti-MDA5) and suggest consideration of dermatomyositis as a diagnosis in patients presenting with systemic illness and markedly elevated ferritin, even in the absence of elevated muscle enzymes and classic autoantibodies. [ABSTRACT FROM AUTHOR]

Objectives To identify clinical factors associated with cancer risk in the idiopathic inflammatory myopathies (IIMs) and to systematically review the existing evidence related to cancer screening. Methods A systematic literature search was carried out on Medline, Embase and Scopus. Cancer risk within the IIM population (i.e. not compared with the general population) was expressed as risk ratios (RR) for binary variables and weighted mean differences (WMD) for continuous variables. Evidence relating to cancer screening practices in the IIMs were synthesized via narrative review. Results Sixty-nine studies were included in the meta-analysis. DM subtype (RR 2.21), older age (WMD 11.19), male sex (RR 1.53), dysphagia (RR 2.09), cutaneous ulceration (RR 2.73) and anti-transcriptional intermediary factor-1 gamma positivity (RR 4.66) were identified as being associated with significantly increased risk of cancer. PM (RR 0.49) and clinically amyopathic DM (RR 0.44) subtypes, Raynaud's phenomenon (RR 0.61), interstitial lung disease (RR 0.49), very high serum creatine kinase (WMD −1189.96) or lactate dehydrogenase (WMD −336.52) levels, and anti-Jo1 (RR 0.45) or anti-EJ (RR 0.17) positivity were identified as being associated with significantly reduced risk of cancer. Nine studies relating to IIM-specific cancer screening were included. CT scanning of the thorax, abdomen and pelvis appeared to be effective in identifying underlying asymptomatic cancers. Conclusion Cancer risk factors should be evaluated in patients with IIM for risk stratification. Screening evidence is limited but CT scanning could be useful. Prospective studies and consensus guidelines are needed to establish cancer screening strategies in IIM patients. [ABSTRACT FROM AUTHOR]

• The intervening Bose metal (BM) state is the bosonic topological insulator. • In the bulk vortices and Cooper pairs are frozen by Aharonov-Bohm interactions. • Transport in the Bose metal is mediated by topologically protected edge modes. • Transitions BM–superinsulator and BM–superconductor are quantum BKT transitions. A low-temperature intervening metallic regime arising in the two-dimensional superconductor-insulator transition challenges our understanding of electronic fluids. Here we develop a gauge theory revealing that this emergent anomalous metal is a bosonic topological insulator where bulk transport is suppressed by mutual statistics interactions between out-of-condensate Cooper pairs and vortices and the longitudinal conductivity is mediated by symmetry-protected gapless edge modes. We explore the magnetic-field-driven superconductor-insulator transition in a niobium titanium nitride device and find marked signatures of a bosonic topological insulator behavior of the intervening regime with the saturating resistance. The observed superconductor-anomalous metal and insulator-anomalous metal dual phase transitions exhibit quantum Berezinskii-Kosterlitz-Thouless criticality in accord with the gauge theory. [ABSTRACT FROM AUTHOR]

A correction to the article "A systematic Review and Meta-analysis to Inform Cancer Screening Guidelines in Idiopathic Inflammatory Myopathies" by Alexander G. S. Oldroyd et al is presented.

We developed novel techniques to fabricate atomically thin Bi2.1Sr1.9CaCu2.0O8+δ van der Waals heterostructures down to two unit cells while maintaining a transition temperature Tc close to the bulk, and carry out magnetotransport measurements on these van der Waals devices. We find a double sign change of the Hall resistance Rxy as in the bulk system, spanning both below and above Tc. Further, we observe a drastic enlargement of the region of sign reversal in the temperature-magnetic field phase diagram with decreasing thickness of the device. We obtain quantitative agreement between experimental Rxy(T,B) and the predictions of the vortex dynamics-based description of Hall effect in high-temperature superconductors both above and below Tc. [ABSTRACT FROM AUTHOR]

Abstract: We present the results of the comparative study of low-temperature transport properties of critically disordered nanoperforated titanium nitride films of the thickness less than the superconducting coherence length, . The samples were patterned by the electron beam lithography and the subsequent plasma etching to form a square array of holes, with the hole diameter being ⩾ and the center to center separation being 80nm. In the wide temperature region below the superconducting critical temperature, , we observe a periodic dependence of the resistance upon the external magnetic field, with the period corresponding to the magnetic flux quantum per unit cell. On top of that we see secondary minima at the half-integer quanta points. We find that the effect of perforation on the low-temperature (⩽) magnetoresistance depends drastically on the degree of disorder. Namely, in the moderately disordered films the perforation results in the shift of magnetoresistance curves towards higher fields as compared to those of the original films, while in the more disordered films , the perforation gives rise to the shift of the magnetoresistance in the opposite direction. [ABSTRACT FROM AUTHOR]