Effect of Ge substitution on first order ferrimagnetic (FRI) -antiferromagnetic (AFM) transition in Mn2Sb has been studied. It shows that transition temperature (Tt) can be tuned between 119 K -271 K by substituting 2.5-10% Ge at Sb site in Mn2Sb. The variation of density of state at Fermi level N(E f ) with Ge substitution shows that dN(E)/dE is positive at E f in the AFM state. With the application of magnetic field Tt shifts to low temperature, which results in a giant negative magnetoresistance (MR) reaching a value of 70% for 2.5% substitution. Our results show that FRI to AFM transformation during cooling stops around 35 K, even though it remains incomplete. It along with non-monotonic variation of lower critical field, open loop in isothermal MR and increasing difference in zero field cooled warming (ZFCW) and field cooled warming (FCW) resistivity with increasing magnetic field shows that FRI to AFM transition is kinetically arrested in the case of 2.5% Ge substitution.

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Niobium nitride (NbN) has attracted scientific interest due to its diverse physical properties and a variety of structural phases. The structure and superconductivity of the cubic [Formula: see text]-NbN phase are well established, but its hexagonal phases are not explored hitherto. In the present work, we report a simple synthesis route and a detailed study of hexagonal [Formula: see text]-Nb2N thin films. Thermal annealing of sputtered grown [Formula: see text]-NbN leads to a single phase [Formula: see text]-Nb2N at 973 K as confirmed by x-ray diffraction and absorption spectroscopy. The electrical transport measurements revealed a dominance of electron–phonon interactions with a superconducting transition around 4.74 K and an upper critical field [[Formula: see text]] of 3.99 T. The estimated [Formula: see text] is well below the calculated Pauli limit, and the Maki parameter value ([Formula: see text] [Formula: see text] 1) indicates that [Formula: see text] is dominated by an orbital pair breaking effect. Finally, the obtained value of electron–phonon coupling constant ([Formula: see text]) is in excellent agreement with a weak coupling Bardeen–Cooper–Schrieffer value of conventional superconducting materials.

A 30-year-old woman presented with an acute-onset high-grade fever (103°F), multiple episodes of throbbing abdominal pain in the right quadrant, and pustular red lesions on the left leg. The radiological findings were suggestive of autoimmune cholangitis and pancreatitis. The skin lesions recurred on different portions of the body, and histopathological findings showed lobular and septal lymphohistiocytic infiltrate without vasculitis. The epidermis had focal ulcerations, and the dermis showed the presence of subcutaneous fat and an infiltrate of lymphocytes, histiocytes, and neutrophils (described as lobular and septal panniculitis without vasculitis). Based on the clinical and histopathological features, a diagnosis of migratory panniculitis was made. The patient was managed with analgesics, antibiotics, and a long course of steroids; the patient responded well to these medications. To the best of our knowledge, this is one of the first case reports of migratory panniculitis associated with IgG4-related disease. Patients with migratory panniculitis should be investigated for the presence of IgG4-related autoimmune disease. However, steroids remain the drug of choice when these conditions occur together.

FeRh 0.8 Pd 0.2 is known to exhibit near room-temperature first-order antiferromagnetic (AF)–ferromagnetic (FM) transition, typical of chemically ordered FeRh system. In addition, it is also reported to show martensitic transition at a lower temperature. In this work, the effect of sample history on transition temperature (Tt) and the magnetocaloric effect (MCE) have been studied. The experimentally determined MCE parameters across FM to AF transition induced either by isothermal magnetic field sweep or by temperature sweep showed a large isothermal change in entropy around room temperature, i.e., 14 J/kg K for 50 kOe magnetic field change, whereas MCE corresponding to AF–FM transition depends on cooling history. Our study shows that in the presence of martensite phase, the peak value of MCE is shifted to higher temperatures but with significantly reduced magnitude.

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