Kinetic arrest of the ferromagnetic state in Mn[Formula: see text]GaC and Ni[Formula: see text]MnGa composite mixtures.

The kinetics of the ferromagnetic to antiferromagnetic transition in Mn[Formula: see text]GaC can be arrested and its magnetic properties can be tuned by mixing a small amount ([Formula: see text] 10%) of Heusler Ni[Formula: see text]MnGa to Mn[Formula: see text]GaC. A detailed study of magnetic properties of composite mixtures of Mn[Formula: see text]GaC and Ni[Formula: see text]MnGa with different antiperovskite to Heusler ratio, reveals that the ferromagnetic Ni[Formula: see text]MnGa polarizes magnetic spins of the antiperovskite phase by creating a magnetic strain field in its vicinity. The Heusler phase acts as a defect centre whose influence on the magnetic properties of the majority antiperovskite phase progressively diminishes, creating a distribution of transition temperatures. Such strong interaction between the two phases of the mixture allows for tunability and control over the properties of such magneto-structurally transforming materials.

Acute effects of exercise on cerebrovascular response and cognitive performance in individuals with stable coronary heart disease.

BACKGROUND: Individuals with coronary heart disease (CHD) exhibit cognitive deficits and cerebrovascular dysfunctions, and are at higher risk of developing dementia. Cognitive function in individuals with CHD has never been studied during acute aerobic exercise. Given the increasing popularity of training at high peak power output (PPO), its impact on cerebrovascular and cognitive functions in individuals with CHD should be further studied. METHOD: Thirty-eight individuals with CHD and 16 healthy controls completed two exercise bouts at 30% and 70% of their individualized PPO on an ergocycle while performing a cognitive task including non-executive and executive conditions. Variations of oxy- deoxy-hemoglobin, and total hemoglobin concentrations were measured on left prefrontal cortex at both PPO using near-infrared spectroscopy. RESULTS: Cognitive task performances were equivalent between groups at all intensity levels. Individuals with CHD exhibited larger variation of deoxyhemoglobin in the executive condition and larger variation in total hemoglobin concentration in all task conditions compared to healthy controls at 70% of PPO. CONCLUSION: Exercising at high intensity seems to have a larger impact on cerebral blood volume in CHD patients compared to healthy age-matched controls. Higher exercise intensity has negative impacts on cerebral blood volume variations during a cognitive task in CHD patients and could potentially lead to other neurocognitive dysfunctions. Other studies are needed to determine if a cognitive task administered during an exercise test could help identify individuals with CHD at higher risk of developing cognitive decline.

Non-equilibrium magnetic response of canonical spin glass and magnetic glass.

Time and history dependent magnetization has been observed in a wide variety of materials, which are collectively termed as the glassy magnetic systems. However, such systems showing similar non-equilibrium magnetic response can be microscopically very different and they can be distinguished by carefully looking into the details of the observed metastable magnetic behavior. Canonical spin glass (SG) is the most well studied member of this class and has been extensively investigated both experimentally and theoretically over the last five decades. In canonical SGs, the low temperature magnetic state obtained by cooling across the SG transition temperature in presence of an applied magnetic field is known as the field cooled (FC) state. This FC state in canonical SG is widely believed as an equilibrium state arising out of a thermodynamic second order phase transition. Here, we show that the FC state in canonical SG is not really an equilibrium state of the system. We report careful dc magnetization and ac susceptibility measurements on two canonical SG systems, AuMn (1.8%) and AgMn (1.1%). The dc magnetization in the FC state shows clear temperature dependence. In addition, the magnetization shows a distinct thermal hysteresis in the temperature regime below the SG transition temperature. On the other hand, the temperature dependence of ac susceptibility has clear frequency dispersion below SG transition in the FC state prepared by cooling the sample in the presence of a dc-bias field. We further distinguish the metastable response of the FC state of canonical SG from the metastable response of the FC state in an entirely different class of glassy magnetic system namely magnetic glass, where the non-equilibrium behavior is associated with the kinetic-arrest of a first order magnetic phase transition.

Lattice strain accommodation and absence of pre-transition phases in Ni50Mn25+xIn25-x.

The stoichiometric Ni50Mn25In25Heusler alloy transforms from a stable ferromagnetic austenitic ground state to an incommensurate modulated martensitic ground state with a progressive replacement of In with Mn without any pre-transition phases. The absence of pre-transition phases like strain glass in Ni50Mn25+xIn25-xalloys is explained to be the ability of the ferromagnetic cubic structure to accommodate the lattice strain caused by atomic size differences of In and Mn atoms. Beyond the critical value ofx= 8.75, the alloys undergo martensitic transformation despite the formation of ferromagnetic and antiferromagnetic clusters and the appearance of a super spin glass state.

Role of Bone Marrow Examination in the Evaluation of Infections: Clinico-Hematological Analysis in a Tertiary Care Centre.

OBJECTIVE: Bone marrow examination (BME) is an important modality for investigation of case of pyrexia of unknown origin (PUO). However, its yield in the diagnosis of infections has not been extensively studied and its role has not been well established. The aim of the study was to investigate the usefulness of BME and to evaluate the etiological and clinico-hematological profile in cases of bone marrow infections. MATERIAL AND METHOD: This was a retrospective study where bone marrow cases were retrieved and a review of bone marrow findings with an infectious etiology from July 2014 to June 2018 was done. Detailed history, clinical examination and hematological parameters at presentation were recorded. Clinico-hematological correlation using descriptive statistics was performed. RESULTS: The study included 55 cases, on analysis of which the maximum number of infections were those of leishmaniasis accounting for 35%, followed by HIV (29%) and tuberculosis (15%). Other etiological agents included fungal infections (histoplasmosis and aspergillosis), Enteric fever, Scrub typhus, parvovirus, falciparum malaria and filariasis. The most common clinical presentation was fever (80%) and the most common clinical finding was splenomegaly (66%). CONCLUSION: Bone marrow examination is an important diagnostic tool to delineate etiological diagnosis in infectious conditions, particularly those presenting with PUO. Moreover, it is particularly important if urgent diagnosis is required or if alternate diagnostic modalities have not revealed a reason for PUO.

Possible glass-like random singlet magnetic state in 1T-TaS2.

Two-dimensional layered transition-metal-dichalcogenide compound 1T-TaS2 shows the rare coexistence of charge density wave (CDW) and electron correlation driven Mott transition. In addition, atomic-cluster spins on the triangular lattice of the CDW state of 1T-TaS2 give rise to the possibility of the exotic spin-singlet state in which quantum fluctuations of spins are strong enough to prevent any long range magnetic ordering down to the temperature absolute zero (0 K). We present here the evidences of a glass-like random singlet magnetic state in 1T-TaS2 at low temperatures through a study of temperature and time dependence of magnetization. Comparing the experimental results with a representative canonical spin-glass system Au(1.8%Mn), we show that this glass-like state is distinctly different from the well established canonical spin-glass state.

Spin phonon coupling in Mn doped HoFeO3 compounds exhibiting spin reorientation behaviour.

An investigation has been carried out on the spin phonon coupling in a series of isostructural polycrystalline orthorhombic (Space group Pnma) compounds HoFe1-X Mn X O3 (x ⩽ 0.6) exhibiting spin reorientation below Néel temperature (T N), using magnetization, neutron diffraction, and Raman scattering techniques. Mn doping leads to an anomalous increase in the spin reorientation temperature (T SR), shifting it close to room temperature from T SR ~ 60 K for x = 0 sample, and concomitant lowering of T N. The T SR is absent in samples for x ⩾ 0.5. The magnetic structure undergoes a transition at T SR from Γ4 → Γ1 in the Mn doped compounds as against Γ4 → Γ2 observed in HoFeO3 sample. In the region T < T N an anomalous softening of Raman phonon modes viz., B 2g(5) and B 3g(3), identified with the stretching motion and breathing mode, respectively, of Fe/Mn-O6 octahedra, is observed in compounds exhibiting spin-reorientation behaviour, indicating a spin-phonon coupling in these compounds. A quadratic correlation between the deviation of phonon frequency and variation of antiferromagnetic moment (Δω [Formula: see text] M 2) is observed in these compounds. The temperature evolution of the M2+ mode obtained from the analysis of neutron diffraction data based on symmetry adapted mode decomposition of the Pnma structure further corroborates the mode softening observation.

Comparative analysis of 2-week glycaemic profile of healthy versus mild gestational diabetic pregnant women using flash glucose monitoring system: an observational study.

OBJECTIVE: To compare glycaemic profiles in women with mild gestational diabetes (GDM) and those with a healthy pregnancy. DESIGN: Observational study. SETTING: Hospital-based. POPULATION: Healthy nonpregnant, healthy pregnant, and women with GDM, diagnosed by oral glucose tolerance test. METHODS: Nine nonpregnant women, 33 healthy pregnant women, 29 pregnant women with GDM between 24 and 36 weeks' gestation, received ambulatory glucose profile (AGP) monitoring for a 2-week period. AGP values were compared in the three groups: 100 days (9600 data points) for nonpregnant women, 396 days (33 792 data points) for healthy pregnant women, and 348 days (34 408 data points) for women with GDM. RESULTS: Mean glucose values for fasting and postmeals were highest in nonpregnant healthy women and lowest in healthy pregnant women (P < 0.001). Women with mild GDM had significantly higher blood glucose values than did healthy pregnant women, though still within the target range. Blood glucose values >160 mg/dl were observed in 41.4% (12/29) in the GDM group compared with 18.2% in women with a healthy pregnancy. The maximum peak of day and night time glucose was respectively 234 and 215 mg/dl in women with GDM compared with 183 and 171 mg/dL in the control group. Glycaemic variability as measured by interquartile range was higher in GDM pregnancies. CONCLUSIONS: Although the blood glucose level remained within the target levels in women with mild GDM, glycaemic variability and mean blood glucose levels were significantly higher among women with GDM than among women with a healthy pregnancy. TWEETABLE ABSTRACT: Average blood glucose levels and glycaemic variability are significantly higher in women with GDM than in women with a healthy pregnancy.

Unraveling the physical properties and superparamagnetism in anti-site disorder controlled Fe2TiSn.

With an aim to control the anti-site disorder between Fe and Ti atoms in the full Heusler alloy, Fe[Formula: see text]TiSn, we substitute a small percentage of Ti at Fe site to form the Fe[Formula: see text]Ti[Formula: see text]Sn ([Formula: see text]) series. Using the incident x-rays tuned to the Fe K-edge absorption energy, we record the high resolution synchrotron x-ray diffraction profiles and unambiguously show the reduction in anti-site disorder. In particular, the Fe-Ti anti-site disorder decreases up to an excess Ti content of 0.07; further increase of Ti content leads to disorder between Ti-Sn sites. Detailed characterization vis-á-vis the excess Ti content has been carried out in terms of its thermal and electrical transport, and magnetic properties. Signatures of strong spin fluctuation are seen in all the physical properties reported here. The much disputed high value of the Sommerfeld constant has been shown to be a resultant of such strong spin fluctuations, thus ruling out the long standing controversy of heavy fermionic nature of Fe[Formula: see text]TiSn. Magnetization and the Seebeck coefficient show clear dependence on the disorder. Both dc and ac magnetic measurements reveal the low temperature superparamagnetic nature of this system, comprising of large magnetic clusters [Formula: see text]3 nm in size.

Spectrum of clinicohematological profile and its correlation with average parasite density in visceral leishmaniasis.

BACKGROUND: Leishmaniasis is the prevalent in tropical and subtropical regions of the world. Demonstration of Leishman-Donovan (LD) bodies in the bone marrow aspirates (BMA) is vital to diagnosis of visceral leishmaniasis (VL). In the present study, we studied the clinicohematological parameters encountered in VL and correlated them with parasite load on BMA. METHODS: Retrospective analysis over 3 years was done; clinical details, biochemical profile, complete hemogram with peripheral smear findings, and BMA smears were reviewed and average parasite density (APD) calculated in each case. Multivariate analysis and tests of significance were applied. RESULTS: The study included 28 patients. Splenomegaly showed a positive trend with APD. rK39 antigen detection test was 100% positive in select cases. A strong negative correlation was observed between albumin to globulin ratio and grade of APD. BMA revealed hemophagocytosis (HPS) in 78.57% cases and it had a significant strong correlation with APD (P = 0.014). A significant correlation was also observed between APD and bone marrow plasma cell percentage (P = 0.01). LD bodies were noted in unusual locations such as within myelocytes (14.2%), plasma cells (7.1%), and megakaryocytes (10.7%). CONCLUSION: HPS and bone marrow plasmacytosis were two statistically significant findings, which showed positive correlation with parasite load. The presence of these two findings should prompt hematopathologists for more focused search of hemoparasites in BMA to arrive at a definitive diagnosis. This will avoid unnecessary workups and improve the prognosis. To the best of our knowledge, a statistical correlation between APD and clinicohematological parameters has never been previously studied.

Possible half-metallicity and variable range hopping transport in Sb-substituted Fe2TiSn Heusler alloys.

The investigation of the magnetotransport properties on [Formula: see text] [Formula: see text]Sb x with 0 [Formula: see text] 0.6 are presented in this paper. The substitution of Sb in place of Sn decreases the anti-site disorder as evident from x-ray diffraction patterns as well as from transport properties measurement. The much-disputed upturn in low temperature electrical resistivity of [Formula: see text]TiSn has been demonstrated to be a result of weak localization induced by anti-site disorder. With increased Sb substitution (⩾25%) the metallic transport behavior of [Formula: see text]TiSn changes to semiconductor-like. At low temperature, carrier transport in such compositions occurs via the variable range hopping mechanism. Moreover, a systematic increase in the anomalous Hall voltage is observed with increasing Sb-content, attributable to a side jump or Berry phase curvature effect. Electrical resistivity in the entire temperature regime hints towards half metallicity of the system. Our ab initio electronic structure calculations using generalised gradient approximation formalism further supports the results of our magnetotransport study.

Study of the sign change of exchange bias across the spin reorientation transition in Co(Cr1-x Fe x )2O4 (x = 0.00-0.125).

We present the evolution of novel phenomena of magnetic compensation effect, exchange bias (EB) effect and the field induced anomalies in '[Formula: see text]' substituted multiferroic compound [Formula: see text]. A few percent of '[Formula: see text]' substitution for '[Formula: see text]' in [Formula: see text] results in the reversal of field cooled magnetization under low applied fields below compensation temperature T comp. Further, increase in the field leads to the spin reorientation transition (T SR). Signature of EB in a narrow temperature window in the vicinity of T SR and its sign change across T SR is observed. Magnitude of EB depends on the amount of compensation and rigidity of the spin reorientation. We also notice the appearance of positive EB below the lock-in transition (T L). Presence of unidirectional anisotropy developed in the commensurate spin-spiral below T L could be responsible for the appearance of EB below T L.

Validity and reproducibility of a food frequency questionnaire focused on the Mediterranean diet for the Quebec population.

BACKGROUND AND AIMS: Validated dietary assessment methods specific to population and food habits are needed to conduct randomized clinical trials evaluating the efficacy of the Mediterranean diet in primary and secondary prevention of cardiovascular disease. Therefore, the aim of our study was to assess the reproducibility and the relative validity of a French language semi-quantitative food frequency questionnaire (FFQ) focused on the Mediterranean diet within the population of Quebec. METHODS AND RESULTS: Fifty-three participants aged 19-86 years with and without coronary heart disease were recruited, and randomized in 3 groups in a crossover design where the sequence of administration of two FFQs and a dietary record (DR) differed in each group. The FFQ includes 157 food items and was designed to measure food intake over one month. It was administered twice 3-5 weeks apart to assess reproducibility and was compared to a 12-day DR to assess validity. For reproducibility (n = 47), intraclass correlation coefficients (ICCs) for energy and 33 nutrients ranged from 0.38 to 0.91 (mean 0.63). For validity, the Pearson's correlation coefficients between the DR and the FFQ pre-DR ranged from 0.26 to 0.84 (mean 0.55) and ICCs ranged from 0.25 to 0.84 (mean 0.54). As for the DR and the FFQ post-DR, the Pearson's correlation coefficients ranged from 0.36 to 0.83 (mean 0.55) and the ICCs ranged from 0.36 to 0.83 (mean 0.53). CONCLUSION: This FFQ demonstrates good reproducibility and validity for most key nutrients of the Mediterranean diet for the Quebec population.

Salivary gland myoepithelial carcinoma

Salivary gland myoepithelial carcinoma (MC) or malignant myoepithelioma is a rare entity. MC usually presents as a slow-growing painless mass arising in the parotid gland, but may involve other salivary glands. This tumour may be particularly locally aggressive, but its clinical and biological features are not yet fully understood. MC may arise from pre-existing benign lesions, such as pleomorphic adenomas or benign myoepitheliomas, or may arise de novo. It usually affects patients over 50 years old, with no gender preference. Because it is often asymptomatic, the presentation and diagnosis can be delayed by months, even years. The current WHO classification considers MC to be an intermediate- to high-grade malignancy. Other published data suggest it is likely to be a high-grade neoplasm, consistent with its aggressive behaviour. Its epidemiology, histopathological features, immunohistochemical profile, clinical behaviour and optimal management are not well understood. Following review of the current literature we aim to address these (AU)

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Salivary gland myoepithelial carcinoma.

Salivary gland myoepithelial carcinoma (MC) or malignant myoepithelioma is a rare entity. MC usually presents as a slow-growing painless mass arising in the parotid gland, but may involve other salivary glands. This tumour may be particularly locally aggressive, but its clinical and biological features are not yet fully understood. MC may arise from pre-existing benign lesions, such as pleomorphic adenomas or benign myoepitheliomas, or may arise de novo. It usually affects patients over 50 years old, with no gender preference. Because it is often asymptomatic, the presentation and diagnosis can be delayed by months, even years. The current WHO classification considers MC to be an intermediate- to high-grade malignancy. Other published data suggest it is likely to be a high-grade neoplasm, consistent with its aggressive behaviour. Its epidemiology, histopathological features, immunohistochemical profile, clinical behaviour and optimal management are not well understood. Following review of the current literature we aim to address these.

Characterization of bipolar disorder patient-specific induced pluripotent stem cells from a family reveals neurodevelopmental and mRNA expression abnormalities.

Bipolar disorder (BD) is a common neuropsychiatric disorder characterized by chronic recurrent episodes of depression and mania. Despite evidence for high heritability of BD, little is known about its underlying pathophysiology. To develop new tools for investigating the molecular and cellular basis of BD, we applied a family-based paradigm to derive and characterize a set of 12 induced pluripotent stem cell (iPSC) lines from a quartet consisting of two BD-affected brothers and their two unaffected parents. Initially, no significant phenotypic differences were observed between iPSCs derived from the different family members. However, upon directed neural differentiation, we observed that CXCR4 (CXC chemokine receptor-4) expressing central nervous system (CNS) neural progenitor cells (NPCs) from both BD patients compared with their unaffected parents exhibited multiple phenotypic differences at the level of neurogenesis and expression of genes critical for neuroplasticity, including WNT pathway components and ion channel subunits. Treatment of the CXCR4(+) NPCs with a pharmacological inhibitor of glycogen synthase kinase 3, a known regulator of WNT signaling, was found to rescue a progenitor proliferation deficit in the BD patient NPCs. Taken together, these studies provide new cellular tools for dissecting the pathophysiology of BD and evidence for dysregulation of key pathways involved in neurodevelopment and neuroplasticity. Future generation of additional iPSCs following a family-based paradigm for modeling complex neuropsychiatric disorders in conjunction with in-depth phenotyping holds promise for providing insights into the pathophysiological substrates of BD and is likely to inform the development of targeted therapeutics for its treatment and ideally prevention.