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1.
Phys Rev Lett ; 121(7): 077002, 2018 Aug 17.
Article in English | MEDLINE | ID: mdl-30169060

ABSTRACT

We show that a wide class of layered superconductor-ferromagnet (S/F) hybrids demonstrates the emergence of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase well below the superconducting transition temperature. By decreasing the temperature, one can switch the system from uniform to the FFLO state which is accompanied by the damping of the diamagnetic Meissner response down to zero and also by the sign change in the curvature of the current-velocity dependence. Our estimates show that an additional layer of the normal metal (N) covering the ferromagnet substantially softens the conditions required for the predicted FFLO instability, and for existing S/F/N systems, the temperature of the transition into the FFLO phase can reach several kelvins.

2.
Alcohol Alcohol ; 49(1): 118-22, 2014.
Article in English | MEDLINE | ID: mdl-24226811

ABSTRACT

In response to our suggestion to define substance use disorders via 'heavy use over time', theoretical and conceptual issues, measurement problems and implications for stigma and clinical practice were raised. With respect to theoretical and conceptual issues, no other criterion has been shown, which would improve the definition. Moreover, heavy use over time is shown to be highly correlated with number of criteria in current DSM-5. Measurement of heavy use over time is simple and while there will be some underestimation or misrepresentation of actual levels in clinical practice, this is not different from the status quo and measurement of current criteria. As regards to stigma, research has shown that a truly dimensional concept can help reduce stigma. In conclusion, 'heavy use over time' as a tangible common denominator should be seriously considered as definition for substance use disorder.


Subject(s)
Social Stigma , Substance-Related Disorders/diagnosis , Substance-Related Disorders/psychology , Diagnostic and Statistical Manual of Mental Disorders , Humans , Substance-Related Disorders/therapy , Time Factors
3.
Alcohol Alcohol ; 48(6): 633-40, 2013.
Article in English | MEDLINE | ID: mdl-23926213

ABSTRACT

AIMS: The aim of the study was to explore whether the concept of heavy substance use over time can be used as definition of substance use disorder. METHODS: Narrative review. RESULTS: Heavy use over time clearly underlies the neurobiological changes associated with current thinking of substance use disorders. In addition, there is evidence that heavy use over time can explain the majority of social problems and of burden of disease (morbidity and mortality). A definition of substance use disorders via heavy use over time would avoid some of the problems of current conceptualizations, for instance the cultural specificity of concepts such as loss of control. Finally, stressing the continuum of use may avoid the high level of stigmatization currently associated with substance use disorders. CONCLUSION: 'Heavy substance use over time' seems to be a definition of substance use disorders in line with results of basic research and epidemiology. Additionally, it reduces stigmatization. This approach should thus be further explored.


Subject(s)
Substance-Related Disorders/psychology , Humans , Substance-Related Disorders/complications , Substance-Related Disorders/diagnosis , Terminology as Topic
4.
Phys Rev Lett ; 109(23): 237006, 2012 Dec 07.
Article in English | MEDLINE | ID: mdl-23368248

ABSTRACT

We study peculiarities of the proximity effect in clean superconductor-ferromagnet structures caused by either the spatial or momentum dependence of the exchange field. Even a small modulation of the exchange field along the quasiparticle trajectories is shown to provide a long-range contribution to the supercurrent due to the specific interference of particle- and holelike wave functions. The momentum dependence of the exchange field caused by the spin-orbit interaction results in long-range superconducting correlations even in the absence of a ferromagnetic domain structure and can explain recent experiments on ferromagnetic nanowires.

6.
Addict Behav ; 112: 106649, 2021 01.
Article in English | MEDLINE | ID: mdl-32979691

ABSTRACT

OBJECTIVE: Substance use disorders (SUD) are frequently comorbid with other psychiatric conditions, but a comprehensive diagnostic assessment is often not feasible clinically. Efficient psychometrically-validated screening tools exist for commonly comorbid conditions, but cutoff accuracies have typically not been evaluated in addiction treatment settings. This study examined the performance of several widely-used screening measures in relation to diagnostic status from a clinical interview to identify and validate cutoff scores in an inpatient SUD treatment setting. METHOD: Participants were 99 patients in a large residential SUD treatment program in Ontario, Canada. Participants completed a screening battery, including the Patient Health Questionnaire - 9 (PHQ-9), Generalized Anxiety Disorder - 7 (GAD-7), and Post-Traumatic Stress Disorder Checklist-5 (PCL-5), and underwent a semi-structured diagnostic clinical interview. Receiver operating characteristic curves were used to determine optimal cutoff scores on the screening tool against the interview-based diagnosis. RESULTS: Area under the curve (AUC) was statistically significant for all screens and were as follows: PHQ-9 = 0.70 (95% CI = 0.59-0.80), GAD-7 = 0.74 (95% CI = 0.63-0.84), and PCL-5 = 0.79 (95% CI = 0.66-0.91). The optimal accuracy cutoff scores based on sensitivity and specificity were: PHQ-9 ≥ 16, GAD-7 ≥ 9, the PCL-5 ≥ 42. CONCLUSIONS: In general, the candidate screeners performed acceptably in this population. However, the optimal cutoff scores were notably higher than existing guidelines for depression and PTSD, potentially due to the general elevations in negative affectivity among individuals initiating SUD treatment. Further validation of these cutoff values is warranted. PUBLIC HEALTH SIGNIFICANCE: This study provides modified screening cutoff scores for major depression, anxiety disorders, and post-traumatic stress disorder in addiction treatment settings.


Subject(s)
Anxiety Disorders , Depression , Stress Disorders, Post-Traumatic , Anxiety Disorders/diagnosis , Anxiety Disorders/epidemiology , Depression/diagnosis , Humans , Inpatients , Mass Screening , Ontario/epidemiology , Psychometrics , Sensitivity and Specificity , Stress Disorders, Post-Traumatic/diagnosis , Stress Disorders, Post-Traumatic/epidemiology
7.
Epidemiol Infect ; 138(12): 1789-95, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20380771

ABSTRACT

The aim of this study was to quantify the association between alcohol consumption and incidence of pneumonia and to examine possible pathways. This was done by a systematic review and meta-analyses on the dose-response relationship between alcohol consumption or alcohol-use disorders and the incidence of community-acquired pneumonia (CAP). The relative risk (RR) of CAP increased monotonically with increasing alcohol consumption. Individuals consuming 24, 60, and 120 g of pure alcohol daily demonstrated RRs for incident CAP of 1·12 (95% CI 1·02-1·23), 1·33 (95% CI 1·06-1·67) and 1·76 (95% CI 1·13-2·77), respectively, relative to non-drinkers. Clinically defined alcohol-use disorders were associated with an eightfold increased risk of CAP (RR 8·22, 95% CI 4·85-13·95). In conclusion, alcohol was found to be a risk factor for pneumonia with a clear statistical association, and a monotonic dose-response relationship.


Subject(s)
Alcohol Drinking/adverse effects , Pneumonia/epidemiology , Community-Acquired Infections/epidemiology , Female , Humans , Incidence , Male , Risk Factors
8.
Sci Rep ; 4: 5671, 2014 Jul 11.
Article in English | MEDLINE | ID: mdl-25011929

ABSTRACT

Josephson junctions with a ferromagnetic metal weak link reveal a very strong decrease of the critical current compared to a normal metal weak link. We demonstrate that in the ballistic regime the presence of a small region with a non-collinear magnetization near the center of a ferromagnetic weak link restores the critical current inherent to the normal metal. The above effect can be stimulated by additional electrical bias of the magnetic gate which induces a local electron depletion of ferromagnetic barrier. The underlying physics of the effect is the interference phenomena due to the magnetic scattering of the Cooper pair, which reverses its total momentum in the ferromagnet and thus compensates the phase gain before and after the spin-reversed scattering. In contrast with the widely discussed triplet long ranged proximity effect we elucidate a new singlet long ranged proximity effect. This phenomenon opens a way to easily control the properties of SFS junctions and inversely to manipulate the magnetic moment via the Josephson current.


Subject(s)
Magnets/chemistry , Metals/chemistry , Nanotechnology/methods , Nanowires/chemistry , Electric Conductivity , Electrons , Magnetics/methods
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