Effect of short range order on electronic and magnetic properties of disordered Co based alloys

We here study electronic structure and magnetic properties of disordered CoPd and CoPt alloys using Augmented Space Recursion technique coupled with the tight-binding linearized muffin tin orbital (TB-LMTO) method. Effect of short range ordering present in disordered phase of alloys on electronic and magnetic properties has been discussed. We present results for magnetic moments, Curie temperatures and electronic band energies with varying degrees of short range order for different concentrations of Co and try to understand and compare the magnetic properties and ordering phenomena in these systems.Comment: 15 pages,17 postscript figures,uses own style file

Pressure-induced collapsed-tetragonal phase in SrCo2As2

We present high-energy x-ray diffraction data under applied pressures up to p = 29 GPa, neutron diffraction measurements up to p = 1.1 GPa, and electrical resistance measurements up to p = 5.9 GPa, on SrCo2As2. Our x-ray diffraction data demonstrate that there is a first-order transition between the tetragonal (T) and collapsed-tetragonal (cT) phases, with an onset above approximately 6 GPa at T = 7 K. The pressure for the onset of the cT phase and the range of coexistence between the T and cT phases appears to be nearly temperature independent. The compressibility along the a-axis is the same for the T and cT phases whereas, along the c-axis, the cT phase is significantly stiffer, which may be due to the formation of an As-As bond in the cT phase. Our resistivity measurements found no evidence of superconductivity in SrCo2As2 for p <= 5.9 GPa and T >= 1.8 K. The resistivity data also show signatures consistent with a pressure-induced phase transition for p >= 5.5 GPa. Single-crystal neutron diffraction measurements performed up to 1.1 GPa in the T phase found no evidence of stripe-type or A-type antiferromagnetic ordering down to 10 K. Spin-polarized total-energy calculations demonstrate that the cT phase is the stable phase at high pressure with a c/a ratio of 2.54. Furthermore, these calculations indicate that the cT phase of SrCo2As2 should manifest either A-type antiferromagnetic or ferromagnetic order.Comment: 6 pages, 5 figure

The mechanism of auricular paroxysmal tachycardia

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32584/1/0000713.pd

MOBILE and the provision of total joint replacement

Modern joint replacements have been available for 45 years, but we still do not have clear indications for these interventions, and we do not know how to optimize the outcome for patients who agree to have them done. The MOBILE programme has been investigating these issues in relation to primary total hip and knee joint replacements, using mixed methods research

Auricular paroxysmal tachycardia with auriculoventricular block,

1. 1. Seventeen previously reported cases of auricular paroxysmal tachycardia with auriculoventricular block are reviewed, and eighteen additional cases are reported.2. 2. This arrhythmia may occur at almost any age, and in persons with otherwise normal hearts or with organic heart disease.3. 3. The attacks are often of long duration, i.e., they commonly last several days or longer.4. 4. High-grade disability is common in patients with organic heart disease, but sometimes occurs in those with otherwise normal hearts. One patient without significant organic heart disease died of cardiac exhaustion and failure attributable entirely to the long continued tachycardia.5. 5. In some cases the auricular deflections of the electrocardiogram are small or not readily apparent in limb leads. In such instances precordial or esophageal leads are especially valuable because they yield prominent auricular waves and thus permit the identification of the arrhythmia. Such curves are quite different from those of auricular flutter, in that the auricular deflections are separated by periods of electrical quiescence, with the curve at rest on the base line.6. 6. Digitalis in large amounts often restores normal rhythm. Quinidine and quinine are somewhat less effective, but sometimes restore normal rhythm, occasionally even when digitalis has failed to do so. Pressure upon the carotid sinus rarely terminates the paroxysms; it was successful in only one case (Mackinnon9). Mecholyl and acetylcholine have been ineffectual. Some patients may not respond to any of these measures; in one such instance normal rhythm returned spontaneously after a period of rest in bed, whereas, in another, death resulted from cardiac exhaustion caused by the prolonged tachycardia.7. 7. Auricular paroxysmal tachycardia with partial A-V block resembles auricular flutter in many respects, but differs from it in some important particulars. Most of the features of auricular paroxysmal tachycardia can be accounted for by circus rhythm involving either the sinoauricular node or the auriculoventricular node.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32589/1/0000718.pd

On Einthoven's triangle, the theory of unipolar electrocardiographic leads, and the interpretation of the precordial electrocardiogram,

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32566/1/0000692.pd

The chaperone protein clusterin may serve as a cerebrospinal fluid biomarker for chronic spinal cord disorders in the dog

Chronic spinal cord dysfunction occurs in dogs as a consequence of diverse aetiologies, including long-standing spinal cord compression and insidious neurodegenerative conditions. One such neurodegenerative condition is canine degenerative myelopathy (DM), which clinically is a challenge to differentiate from other chronic spinal cord conditions. Although the clinical diagnosis of DM can be strengthened by the identification of the Sod1 mutations that are observed in affected dogs, genetic analysis alone is insufficient to provide a definitive diagnosis. There is a requirement to identify biomarkers that can differentiate conditions with a similar clinical presentation, thus facilitating patient diagnostic and management strategies. A comparison of the cerebrospinal fluid (CSF) protein gel electrophoresis profile between idiopathic epilepsy (IE) and DM identified a protein band that was more prominent in DM. This band was subsequently found to contain a multifunctional protein clusterin (apolipoprotein J) that is protective against endoplasmic reticulum (ER) stress-mediated apoptosis, oxidative stress, and also serves as an extracellular chaperone influencing protein aggregation. Western blot analysis of CSF clusterin confirmed elevated levels in DM compared to IE (p &#60; 0.05). Analysis of spinal cord tissue from DM and control material found that clusterin expression was evident in neurons and that the clusterin mRNA levels from tissue extracts were elevated in DM compared to the control. The plasma clusterin levels was comparable between these groups. However, a comparison of clusterin CSF levels in a number of neurological conditions found that clusterin was elevated in both DM and chronic intervertebral disc disease (cIVDD) but not in meningoencephalitis and IE. These findings indicate that clusterin may potentially serve as a marker for chronic spinal cord disease in the dog; however, additional markers are required to differentiate DM from a concurrent condition such as cIVDD

Evaluation of Messages to Promote Intake of Calcium-Rich Foods in Early Adolescents

Parental practices influence intake of calcium-rich foods and beverages (CRFB) in adolescents. This study aimed to test two posters promoting such parental practices for comprehension, cultural and personal relevance, and ability to motivate parents to encourage CRFB intake. Interviews were conducted with 14 Hispanic and 6 Asian parents to evaluate two posters entitled “Good play starts with calcium” and “Strong families start with good nutrition.” Responses were reviewed for themes. For “Good play,” both racial/ethnic groups of parents understood the message to provide CRFB. Only Hispanics, however, recognized the connection between calcium and strong bones. For “Strong families,” both groups had difficulty understanding that foods pictured were calcium rich. Both posters were considered culturally and personally relevant; however, not all respondents indicated motivation to provide CRFB. Modifications are needed to emphasize the connection between images and taglines and calcium intake for use in a future intervention to improve CRFB-promoting practices

Magnetic detwinning and biquadratic magnetic interaction in EuFe2As2 revealed by Eu-153 NMR

In the nematic state of iron-based superconductors, twin formation often obscures the intrinsic, anisotropic, in-plane physical properties. Relatively high in-plane external magnetic fields Hext greater than the typical laboratory-scale magnetic fields 10–15 T are usually required to completely detwin a sample. However, recently a very small in-plane Hext∼0.1 T was found to be sufficient for detwinning the nematic domains in EuFe2As2. To explain this behavior, a microscopic theory based on biquadratic magnetic interactions between the Eu and Fe spins has been proposed. Here, using 153Eu nuclear magnetic resonance (NMR) measurements below the Eu2+ ordering temperature, we show experimental evidence of the detwinning under small in-plane Hext. Our NMR study also reveals the evolution of the angles between the Eu and Fe spins during the detwinning process, which provides experimental evidence for the existence of biquadratic coupling in the system

Limited Durability of Viral Control following Treated Acute HIV Infection

BACKGROUND: Early treatment of acute HIV infection with highly active antiretroviral therapy, followed by supervised treatment interruption (STI), has been associated with at least transient control of viremia. However, the durability of such control remains unclear. Here we present longitudinal follow-up of a single-arm, open-label study assessing the impact of STI in the setting of acute HIV-1 infection. METHODS AND FINDINGS: Fourteen patients were treated during acute HIV-1 infection and subsequently subjected to an STI protocol that required retreatment if viral load exceeded 50,000 RNA copies/ml plasma or remained above 5,000 copies/ml for more than three consecutive weeks. Eleven of 14 (79%) patients were able to achieve viral loads of less than 5,000 RNA copies/ml for at least 90 d following one, two, or three interruptions of treatment. However, a gradual increase in viremia and decline in CD4+ T cell counts was observed in most individuals. By an intention-to-treat analysis, eight (57%), six (43%), and three (21%) of 14 patients achieved a maximal period of control of 180, 360, and 720 d, respectively, despite augmentation of HIV-specific CD4+ and CD8+ T cell responses. The magnitude of HIV-1-specific cellular immune responses before treatment interruption did not predict duration of viremia control. The small sample size and lack of concurrent untreated controls preclude assessment of possible clinical benefit despite failure to control viremia by study criteria. CONCLUSIONS: These data indicate that despite initial control of viremia, durable viral control to less than 5,000 RNA copies/ml plasma in patients following treated acute HIV-1 infection occurs infrequently. Determination of whether early treatment leads to overall clinical benefit will require a larger and randomized clinical trial. These data may be relevant to current efforts to develop an HIV-1 vaccine designed to retard disease progression rather than prevent infection since they indicate that durable maintenance of low-level viremia may be difficult to achieve