ABSTRACT
Competition between ground states at phase boundaries can lead to significant changes in properties under stimuli, particularly when these ground states have different crystal symmetries. A key challenge is to stabilize and control the coexistence of symmetry-distinct phases. Using BiFeO3 layers confined between layers of dielectric TbScO3 as a model system, we stabilize the mixed-phase coexistence of centrosymmetric and non-centrosymmetric BiFeO3 phases at room temperature with antipolar, insulating and polar semiconducting behaviour, respectively. Application of orthogonal in-plane electric (polar) fields results in reversible non-volatile interconversion between the two phases, hence removing and introducing centrosymmetry. Counterintuitively, we find that an electric field 'erases' polarization, resulting from the anisotropy in octahedral tilts introduced by the interweaving TbScO3 layers. Consequently, this interconversion between centrosymmetric and non-centrosymmetric phases generates changes in the non-linear optical response of over three orders of magnitude, resistivity of over five orders of magnitude and control of microscopic polar order. Our work establishes a platform for cross-functional devices that take advantage of changes in optical, electrical and ferroic responses, and demonstrates octahedral tilts as an important order parameter in materials interface design.
ABSTRACT
Petersdorf and Beeson first defined fever of unknown origin (FUO) in 1961, and subsequently, over the next 60 years, the definition of FUO has changed considerably. In the western world, non-infectious inflammatory diseases are the most common cause of FUO; however, in developing countries, infections remain the leading cause of FUO. Dermatomyositis (DM) is an autoimmune inflammatory disease of unknown aetiology which mainly affects skin and muscles. Anti-melanoma differentiation-associated protein 5 (MDA-5) positive DM generally presents with classical cutaneous manifestations, early interstitial lung disease, and patients generally do not have clinical features of muscle involvement. We present a case of a 39-year-old male who presented with FUO and hepatitis and was diagnosed as clinically amyopathic DM after two weeks of admission. Subsequently, he was found to have a high titre of Anti-MDA-5 antibody. This is the first case of Anti-MDA-5 positive DM presenting as FUO and hepatitis with a favourable outcome to the best of our knowledge.
ABSTRACT
BACKGROUND AND AIMS: Diabetes is a frequent comorbidity in patients with Severe COVID-19 infection associated with a worse prognosis. Hypercoagulability with elevation in D-dimer levels has been demonstrated in patients with COVID-19. This study aims to study D-dimer levels in people with diabetes compared to those without diabetes among patients with COVID-19 infection. METHODS: In this observational study 98 moderate and severely ill patients with COVID-19 infection were included at a dedicated COVID hospital. The study group was divided into patients with diabetes and without diabetes. Peak D-dimer was measured in both the groups and compared using appropriate statistical tests. RESULTS: In our study peak D-dimer levels were 1509 ± 2420 ng/mL (Mean ± SD) in people with diabetes and 515 ± 624 ng/mL (Mean ± SD) in patients without diabetes. Patients with diabetes had higher D-dimer levels which were statistically significant. CONCLUSIONS: This study shows COVID-19 patients with diabetes had significantly higher D-dimer levels. Therefore, it is possible that COVID-19 infection with diabetes is more likely to cause hypercoagulable state with a worse prognosis. However clinical implications of these findings will need to be seen in further studies.
