Inelastic Scattering from Local Vibrational Modes

We study a nonuniversal contribution to the dephasing rate of conduction electrons due to local vibrational modes. The inelastic scattering rate is strongly influenced by multiphonon excitations, exhibiting oscillatory behaviour. For higher frequencies, it saturates to a finite, coupling dependent value. In the strong coupling limit, the phonon is almost completely softened, and the inelastic cross section reaches its maximal value. This represents a magnetic field insensitive contribution to the dephasing time in mesoscopic systems, in addition to magnetic impurities.Comment: 5 pages, 3 figure

RPA Green's Functions of the Anisotropic Heisenberg Model

We solve in random-phase approximation the anisotropic Heisenberg model, including nearest and next-nearest neighbour interactions by calculating all Green's functions and pair correlation functions in a cumulant decoupling scheme. The general exposition is pedagogic in tone and is intended to be accessible to any graduate student or physicist who is not an expert in the field.Comment: 26 pages, 4 figure

Spin gap and Luttinger liquid description of the NMR relaxation in carbon nanotubes

Recent NMR experiments by Singer et al. [Singer et al. Phys. Rev. Lett. 95, 236403 (2005).] showed a deviation from Fermi-liquid behavior in carbon nanotubes with an energy gap evident at low temperatures. Here, a comprehensive theory for the magnetic field and temperature dependent NMR 13C spin-lattice relaxation is given in the framework of the Tomonaga-Luttinger liquid. The low temperature properties are governed by a gapped relaxation due to a spin gap (~ 30K), which crosses over smoothly to the Luttinger liquid behaviour with increasing temperature.Comment: 5 pages, 1 figure, 1 tabl

Validity and reliability of the 9‑item Shared Decision Making Questionnaire (SDM‑Q‑9) in a national survey in Hungary

Background The nine-item Shared Decision Making Questionnaire (SDM-Q-9) is one of the most frequently applied instruments for assessing patients’ involvement in medical decision-making. Our objectives were to develop a Hungarian version of SDM-Q-9, to evaluate its psychometric properties and to compare its performance between primary and specialised care settings. Methods In 2019, a sample of adults (n=537) representative of the Hungarian general population in terms of age, gender and geographic region completed an online survey with respect to a recent health-related decision. Outcome measures included SDM-Q-9 and Control Preferences Scale-post (CPSpost). Item characteristics, internal consistency reliability and the factor structure of SDM-Q-9 were determined. Results The overall ceiling and foor efects for SDM-Q-9 total scores were 12.3% and 2.2%, respectively. An excellent internal consistency reliability (Cronbach’s alpha 0.925) was demonstrated. Exploratory factor analysis resulted in a onefactor model explaining 63.5% of the variance of SDM-Q-9. A confrmatory factor analysis supported the acceptability of this model. Known-groups validity was confrmed with CPSpost categories; mean SDM-Q-9 total scores were higher in the ‘Shared decision’ category (72.6) compared to both ‘Physician decided’ (55.1, p=0.0002) and ‘Patient decided’ (57.2, p=0.0086) categories. In most aspects of validity and reliability, there was no statistically signifcant diference between primary and specialised care. Conclusions The overall good measurement properties of the Hungarian SDM-Q-9 make the questionnaire suitable for use in both primary and specialised care settings. SDM-Q-9 may be useful for health policies targeting the implementation of shared decision-making and aiming to improve efciency and quality of care in Hungary

Validation of the Musculoskeletal Health Questionnaire in a general population sample:a cross-sectional online survey in Hungary

BACKGROUND: The Versus Arthritis Musculoskeletal Health Questionnaire (MSK-HQ) measures symptom severity and health-related quality of life (HRQoL) of people with musculoskeletal (MSK) conditions. We aimed to test the psychometric properties of the MSK-HQ among the general adult population and identify the determinants of MSK-HQ states. In addition, we aimed to explore the relationship between MSK-HQ and standard well-being measurement tools. METHODS: The translation proccess of the MSK-HQ into Hungarian followed the standard methods provided by the developer. A cross-sectional online survey was performed in Hungary involving a population normative sample (N = 2004, women: 53.1%; mean age: 48.3, SD = 16.6 years). Socio-demographic characteristics and self-reported MSK disorders were recorded. Alongside the MSK-HQ, standard measures of HRQoL (EQ-5D-5L), physical functioning (HAQ-DI) and well-being (ICECAP-A/O, WHO-5, Happiness VAS) were applied. Clinical and convergent validity were assessed by subgroup comparisons (Mann–Whitney-U and Kruskal–Wallis tests) and Spearman’s rank correlations. Internal consistency was assessed by Cronbach’s alpha. Test–retest reliability (N = 50) was evaluated by intraclass correlation coefficient (ICC). Predictors of MSK-HQ were analysed by ordinary least square multiple regressions. RESULTS: The mean MSK-HQ index score was 44.1 (SD = 9.9). MSK-HQ scores were significantly lower in subgroups with self-reported MSK disorders. Correlations were strong between MSK-HQ and EQ-5D-5L (0.788), EQ VAS (0.644) and HAQ-DI (-0.698) and moderate with the well-being measures (p < 0.05). Cronbach’s alpha was 0.924 and ICC was 0.936 (p < 0.05). Being a man, living in the capital, having higher income and education were positively associated with MSK-HQ scores. CONCLUSIONS: This is the first study to prove the validity and reliability of the MSK-HQ among the general public. The impact of socio-demographic characteristics on MSK-HQ scores deserves consideration in clinical studies. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12891-022-05716-9

Finite temperature bosonization

Finite temperature properties of a non-Fermi liquid system is one of the most challenging probelms in current understanding of strongly correlated electron systems. The paradigmatic arena for studying non-Fermi liquids is in one dimension, where the concept of a Luttinger liquid has arisen. The existence of a critical point at zero temperature in one dimensional systems, and the fact that experiments are all undertaken at finite temperature, implies a need for these one dimensional systems to be examined at finite temperature. Accordingly, we extended the well-known bosonization method of one dimensional electron systems to finite temperatures. We have used this new bosonization method to calculate finite temperature asymptotic correlation functions for linear fermions, the Tomonaga-Luttinger model, and the Hubbard model.Comment: REVTex, 48 page

Subjective well‑being in patients with pemphigus: a path analysis

Background Pemphigus is a chronic autoimmune blistering disease of the skin and mucosa severely impairing patients’ health-related quality of life (HRQoL). To date, no studies have measured subjective well-being in terms of life satisfaction in pemphigus. Our main objective was to evaluate satisfaction with life in patients with pemphigus, and to analyse its relationship with clinical severity and HRQoL. Methods A cross-sectional survey was carried out enrolling 77 patients with pemphigus. Subjective well-being was measured using the Satisfaction with Life Scale (SWLS). HRQoL was assessed by the Dermatology Life Quality Index (DLQI) and EQ-5D-5L. Disease severity was measured by Autoimmune Bullous Skin Disorder Intensity Score (ABSIS). Results Mean ABSIS, DLQI, EQ-5D-5L and SWLS scores of patients were 11.7 (SD 17.3), 5.4 (6.8), 0.84 (0.22) and 4.76 (SD 1.52), respectively. The proportion of patients indicating extreme dissatisfaction, dissatisfaction, slightly below average in life satisfaction, average satisfaction, high satisfaction and very high satisfaction with life was 6 (7.8%), 5 (6.5%), 14 (18.2%), 16 (20.8%), 21 (27.3%) and 15 (19.5%), respectively. Life satisfaction was independent from age, gender, level of education and type of disease. A path analysis revealed that there was no direct relationship between ABSIS and SWLS (beta=−0.09; p=0.428); however, the following indirect path was confrmed: ABSIS→DLQI→EQ-5D-5L→SWLS. Conclusions Disease severity and HRQoL measures regularly used to assess patients’ health status may be complemented with a measure of subjective well-being, such as SWLS, to achieve a more holistic assessment of patients’ lives and optimise pemphigus care