A Real Space Description of Field Induced Melting in the Charge Ordered Manganites: II. the Disordered Case

We study the effect of A site disorder on magnetic field induced melting of charge order (CO) in half doped manganites using a Monte-Carlo technique. Strong A-site disorder destroys CO even without an applied field. At moderate disorder, the zero field CO state survives but has several intriguing features in its field response. Our spatially resolved results track the broadening of the field melting transition due to disorder and explain the unusual dependence of the melting scales on bandwidth and disorder. In combination with our companion paper on field melting of charge order in clean systems we provide an unified understanding of CO melting across all half doped manganites.Comment: 9 pages, pdflatex, 10 embedded png fig

A Real Space Description of Magnetic Field Induced Melting in the Charge Ordered Manganites: I. The Clean Limit

We study the melting of charge order in the half doped manganites using a model that incorporates double exchange, antiferromagnetic superexchange, and Jahn-Teller coupling between electrons and phonons. We primarily use a real space Monte Carlo technique to study the phase diagram in terms of applied field $(h)$ and temperature $(T)$, exploring the melting of charge order with increasing $h$ and its recovery on decreasing $h$. We observe hysteresis in this response, and discover that the `field melted' high conductance state can be spatially inhomogeneous even without extrinsic disorder. The hysteretic response plays out in the background of field driven equilibrium phase separation. Our results, exploring $h$, $T$, and the electronic parameter space, are backed up by analysis of simpler limiting cases and a Landau framework for the field response. This paper focuses on our results in the `clean' systems, a companion paper studies the effect of cation disorder on the melting phenomena.Comment: 16 pages, pdflatex, 11 png fig

Bilayer manganites: polarons in the midst of a metallic breakdown

The exact nature of the low temperature electronic phase of the manganite materials family, and hence the origin of their colossal magnetoresistant (CMR) effect, is still under heavy debate. By combining new photoemission and tunneling data, we show that in La{2-2x}Sr{1+2x}Mn2O7 the polaronic degrees of freedom win out across the CMR region of the phase diagram. This means that the generic ground state is that of a system in which strong electron-lattice interactions result in vanishing coherent quasi-particle spectral weight at the Fermi level for all locations in k-space. The incoherence of the charge carriers offers a unifying explanation for the anomalous charge-carrier dynamics seen in transport, optics and electron spectroscopic data. The stacking number N is the key factor for true metallic behavior, as an intergrowth-driven breakdown of the polaronic domination to give a metal possessing a traditional Fermi surface is seen in the bilayer system.Comment: 7 pages, 2 figures, includes supplementary informatio

Turner syndrome and associated problems in turkish children: A multicenter study

Objective: Turner syndrome (TS) is a chromosomal disorder caused by complete or partial X chromosome monosomy that manifests various clinical features depending on the karyotype and on the genetic background of affected girls. This study aimed to systematically investigate the key clinical features of TS in relationship to karyotype in a large pediatric Turkish patient population. Methods: Our retrospective study included 842 karyotype-proven TS patients aged 0-18 years who were evaluated in 35 different centers in Turkey in the years 2013-2014. Results: The most common karyotype was 45,X (50.7%), followed by 45,X/46,XX (10.8%), 46,X,i(Xq) (10.1%) and 45,X/46,X,i(Xq) (9.5%). Mean age at diagnosis was 10.2±4.4 years. The most common presenting complaints were short stature and delayed puberty. Among patients diagnosed before age one year, the ratio of karyotype 45,X was significantly higher than that of other karyotype groups. Cardiac defects (bicuspid aortic valve, coarctation of the aorta and aortic stenosi) were the most common congenital anomalies, occurring in 25% of the TS cases. This was followed by urinary system anomalies (horseshoe kidney, double collector duct system and renal rotation) detected in 16.3%. Hashimoto’s thyroiditis was found in 11.1% of patients, gastrointestinal abnormalities in 8.9%, ear nose and throat problems in 22.6%, dermatologic problems in 21.8% and osteoporosis in 15.3%. Learning difficulties and/or psychosocial problems were encountered in 39.1%. Insulin resistance and impaired fasting glucose were detected in 3.4% and 2.2%, respectively. Dyslipidemia prevalence was 11.4%. Conclusion: This comprehensive study systematically evaluated the largest group of karyotype-proven TS girls to date. The karyotype distribution, congenital anomaly and comorbidity profile closely parallel that from other countries and support the need for close medical surveillance of these complex patients throughout their lifespan. © Journal of Clinical Research in Pediatric Endocrinology

Proposing a Tool for Supply Chain Configuration: An Application to Customised Production

The full implementation of collaborative production networks is crucial for companies willing to respond to consumer demand strongly focused on product customisation. This chapter proposes an approach to evaluate the performance of different Supply Chain (SC) configurations in a customised production context. The model is based on discrete-event simulation and is applied to the case of supply chain in the fashion sector to support the comparison between mass and customised production. A prototype web-based interface is also developed and proposed to facilitate the use of the model not only for experts in simulation but for any user in the SC management field

Contextualising adverse events of special interest to characterise the baseline incidence rates in 24 million patients with COVID-19 across 26 databases: a multinational retrospective cohort study

BACKGROUND: Adverse events of special interest (AESIs) were pre-specified to be monitored for the COVID-19 vaccines. Some AESIs are not only associated with the vaccines, but with COVID-19. Our aim was to characterise the incidence rates of AESIs following SARS-CoV-2 infection in patients and compare these to historical rates in the general population. METHODS: A multi-national cohort study with data from primary care, electronic health records, and insurance claims mapped to a common data model. This study's evidence was collected between Jan 1, 2017 and the conclusion of each database (which ranged from Jul 2020 to May 2022). The 16 pre-specified prevalent AESIs were: acute myocardial infarction, anaphylaxis, appendicitis, Bell's palsy, deep vein thrombosis, disseminated intravascular coagulation, encephalomyelitis, Guillain- Barré syndrome, haemorrhagic stroke, non-haemorrhagic stroke, immune thrombocytopenia, myocarditis/pericarditis, narcolepsy, pulmonary embolism, transverse myelitis, and thrombosis with thrombocytopenia. Age-sex standardised incidence rate ratios (SIR) were estimated to compare post-COVID-19 to pre-pandemic rates in each of the databases. FINDINGS: Substantial heterogeneity by age was seen for AESI rates, with some clearly increasing with age but others following the opposite trend. Similarly, differences were also observed across databases for same health outcome and age-sex strata. All studied AESIs appeared consistently more common in the post-COVID-19 compared to the historical cohorts, with related meta-analytic SIRs ranging from 1.32 (1.05 to 1.66) for narcolepsy to 11.70 (10.10 to 13.70) for pulmonary embolism. INTERPRETATION: Our findings suggest all AESIs are more common after COVID-19 than in the general population. Thromboembolic events were particularly common, and over 10-fold more so. More research is needed to contextualise post-COVID-19 complications in the longer term. FUNDING: None

Приклади завдань для позакласної роботи з інформатики у початковій школі

У статті коротко описана методика проведення позакласної роботи з інформатики у початковій школі

Dissolution Control of Mg by Cellulose Acetate–Polyelectrolyte Membranes

Cellulose acetate (CA)-based membranes are used for Mg dissolution control: the permeability of the membrane is adjusted by additions of the polyelectrolyte, poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA). Spin-coated films were characterized with FT-IR, and once exposed to an aqueous solution the film distends and starts acting as a membrane which controls the flow of ions and H2 gas. Electrochemical measurements (linear sweep voltammograms, open-circuit potential, and polarization) show that by altering the CA:PDMAEMA ratio the dissolution rate of Mg can be controlled. Such a control over Mg dissolution is crucial if Mg is to be considered as a viable, temporary biomedical implant material. Furthermore, the accumulation of corrosion products between the membrane and the sample diminishes the undesirable effects of high local pH and H2 formation which takes place during the corrosion process.Peer reviewe