Breakdown of the quantum Hall effect (QHE) is commonly associated with an electric field approaching the inter-Landau-level (LL) Zener field, the ratio of the Landau gap and the cyclotron radius. ...Eluded in semiconducting heterostructures, in spite of extensive investigation, the intrinsic Zener limit is reported here using high-mobility bilayer graphene and high-frequency current noise. We show that collective excitations arising from electron-electron interactions are essential. Beyond a noiseless ballistic QHE regime a large super-Poissonian shot noise signals the breakdown via inter-LL scattering. The breakdown is ultimately limited by collective excitations in a regime where phonon and impurity scattering are quenched. The breakdown mechanism can be described by a Landau critical velocity as it bears strong similarities with the roton mechanism of superfluids. In addition, we show that breakdown is a precursor of an electric-field induced QHE-metal transition.
The periodontal ligament (PDL) is a fibrillar connective tissue that lies between the alveolar bone and the tooth and is composed of highly specialized extracellular matrix (ECM) molecules and a ...heterogeneous population of cells that are responsible for collagen formation, immune response, bone formation, and chewing force sensation. Type VI collagen (COL6), a widely distributed ECM molecule, plays a critical role in the structural integrity and mechanical properties of various tissues including muscle, tendon, bone, cartilage, and skin. However, its role in the PDL remains largely unknown. Our study shows that deficiency of COL6 impairs PDL fibrillogenesis and exacerbates tissue destruction in ligature-induced periodontitis (LIP). We found that COL6-deficient mice exhibited increased bone loss and degraded PDL in LIP and that fibroblasts expressing high levels of Col6α2 are pivotal in ECM organization and cell-ECM interactions. Moreover, COL6 deficiency in the PDL led to an increased number of fibroblasts geared toward the inflammatory response. We also observed that cultured COL6-deficient fibroblasts from the PDL exhibited decreased expression of genes related to collagen fiber turnover and ECM organization as well as migration and proliferation. Our findings suggest that COL6 plays a crucial role in the PDL, influencing fibroblast function in fibrillogenesis and affecting the immune response in periodontitis. These insights advance our understanding of the molecular mechanisms underlying PDL maturation and periodontal disease.
Burning Mouth Syndrome (BMS), a chronic intraoral burning sensation or dysesthesia without clinically evident causes, is one of the most common medically unexplained oral symptoms/syndromes. Even ...though the clinical features of BMS have been astonishingly common and consistent throughout the world for hundreds of years, BMS remains an enigma and has evolved to more intractable condition. In fact, there is a large and growing number of elderly BMS patients for whom the disease is accompanied by systemic diseases, in addition to aging physical change, which makes the diagnosis and treatment of BMS more difficult. Because the biggest barrier preventing us from finding the core pathophysiology and best therapy for BMS seems to be its heterogeneity, this syndrome remains challenging for clinicians. In this review, we discuss currently hopeful management strategies, including central neuromodulators (Tricyclic Antidepressants - TCAs, Serotonin, and Norepinephrine Reuptake Inhibitors - SNRIs, Selective Serotonin Reuptake Inhibitors - SSRIs, Clonazepam) and solutions for applying non-pharmacology approaches. Moreover, we also emphasize the important role of patient education and anxiety management to improve the patients' quality of life. A combination of optimized medication with a short-term supportive psychotherapeutic approach might be a useful solution.
Monoclonal antibodies (mAb) and natural ligands targeting costimulatory tumor necrosis factor receptors (TNFR) exhibit a wide range of agonistic activities and antitumor responses. The mechanisms ...underlying these differential agonistic activities remain poorly understood. Here, we employ a panel of experimental and clinically-relevant molecules targeting human CD40, 4-1BB and OX40 to examine this issue. Confocal and STORM microscopy reveal that strongly agonistic reagents induce clusters characterized by small area and high receptor density. Using antibody pairs differing only in isotype we show that hIgG2 confers significantly more receptor clustering than hIgG1 across all three receptors, explaining its greater agonistic activity, with receptor clustering shielding the receptor-agonist complex from further molecular access. Nevertheless, discrete receptor clustering patterns are observed with different hIgG2 mAb, with a unique rod-shaped assembly observed with the most agonistic mAb. These findings dispel the notion that larger receptor clusters elicit greater agonism, and instead point to receptor density and subsequent super-structure as key determinants.
Atypical Odontalgia (AO) is a condition characterized by tooth pain with no apparent cause. Although psychiatric comorbidity seems to be very common, it has rarely been studied. To clarify the ...influence of psychiatric comorbidity on the clinical features in patients with AO, we retrospectively evaluated their examination records.
Clinical features and psychiatric diagnoses of 383 patients with AO were investigated by reviewing patients' medical records and referral letters. Psychiatric diagnoses were categorized according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). We also analyzed visual analogue scale (VAS), self-rating depression scale (SDS), and the short-form McGill pain questionnaire (SF-MPQ) scores.
Of the 383 patients with AO, 177 (46.2%) had comorbid psychiatric disorders. The most common were depressive disorders (15.4%) and anxiety disorders (10.1%). Serious psychotic disorders such as bipolar disorder (3.0%) and schizophrenia (1.8%) were rare. Dental trigger of AO was reported in 217 (56.7%) patients. There were no significant correlations between psychiatric comorbidities and most of the demographic features. Higher VAS and SDS scores, higher frequency of sleep disturbance, and higher ratings of “Fearful” and “Punishing-cruel” descriptors of the SF-MPQ were found in patients with psychiatric comorbidity.
About half of AO patients had comorbid psychiatric disorders. Dental procedures are not necessarily causative factors of AO. In AO patients with comorbid psychiatric disorders, pain might have a larger emotional component than a sensory one. VAS, SDS, and SF-MPQ scores might aid in the noticing of underlying comorbid psychiatric disorders in AO patients.
•Depression and anxiety disorders are the most common comorbidities in AO patients.•Specific questionnaires might help to notice underlying psychiatric disorders.•Pain might have a larger emotional component than a sensory one in patients with psychiatric-disorders.•Dental procedures are not necessarily causative factors of AO.•A little difference pathophysiology might exist between AO and PIFP.
Numerical techniques for parallel dynamics in electromagnetic gyrokinetic simulations are introduced to regulate unphysical grid-size oscillations in the field-aligned coordinate. It is found that a ...fixed boundary condition and the nonlinear mode coupling in the field-aligned coordinate, as well as numerical errors of non-dissipative finite difference methods, produce fluctuations with high parallel wave numbers. The theoretical and numerical analyses demonstrate that an outflow boundary condition and a low-pass filter efficiently remove the numerical oscillations, providing small but acceptable errors of the entropy variables. The new method is advantageous for quantitative evaluation of the entropy balance that is required for obtaining a steady state in gyrokinetic turbulence.
Objectives
The aim of this study was to examine the reliability and validity of the Job Content Questionnaire (JCQ) in Vietnamese among hospital nursing staff.
Methods
The 22‐items version of the JCQ ...was used. This includes four scales: (a) psychological demands (5 items); (b) job control (9 items); (c) supervisor support (4 items); and (d) coworker support (4 items). All 1258 nurses in a general hospital in Vietnam, excluding 11 who were due to retire, were invited to complete the cross‐sectional survey. The internal consistency reliability was estimated using Cronbach's α. Construct validity was examined using exploratory factor analysis (EFA). Convergent validity was evaluated by calculating correlations between the JCQ scores and DASS 21 and overtime work.
Results
In total, 949 (75%) of the 1258 eligible nurses completed the survey. Cronbach's α values demonstrated acceptable internal consistency in two scales (supervisor support α = .87; coworker support α = .86), while Cronbach's α was below the acceptable threshold of 0.70 for job control (α = .45) and job demand (α = .50). EFA assuming a four‐factor structure showed a factor structure that was almost identical to the original JCQ, with two items loading on other scales. The subscales of depression, anxiety, and stress response of DASS 21 and the subscales of JCQ were significantly correlated, as expected.
Conclusion
The results suggest that the JCQ in Vietnamese can be used with some reliability and validity for examining psychosocial work environment among nurses. Further studies should be done to confirm and expand our findings in a variety of occupational groups and in other Asian low‐ and middle‐income countries.
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