Spintronic magnetic anisotropy

An attractive feature of magnetic adatoms and molecules for nanoscale applications is their superparamagnetism, the preferred alignment of their spin along an easy axis preventing undesired spin reversal. The underlying magnetic anisotropy barrier --a quadrupolar energy splitting-- is internally generated by spin-orbit interaction and can nowadays be probed by electronic transport. Here we predict that in a much broader class of quantum-dot systems with spin larger than one-half, superparamagnetism may arise without spin-orbit interaction: by attaching ferromagnets a spintronic exchange field of quadrupolar nature is generated locally. It can be observed in conductance measurements and surprisingly leads to enhanced spin filtering even in a state with zero average spin. Analogously to the spintronic dipolar exchange field, responsible for a local spin torque, the effect is susceptible to electric control and increases with tunnel coupling as well as with spin polarization.Comment: 6 pages with 4 figures + 26 pages of Supplementary Informatio

Bitopological Harmonious Labeling Of Some Acyclic Graphs By Using Python Program

In this paper, we define a new type of labeling called bitopological harmonious labeling in such a way that for a graph  with vertices, bitopological harmonious labeling is an injective function , where X is any non – empty set such that  and  forms a topology on , that induces an injective function , defined  for every  such that  forms a topology on where . A graph that admits bitopological harmonious labeling is called a bitopological harmonious graph. In this paper, we discuss bitopological harmonious labeling of some acyclic graphs and to generate these labels by using python program code

Centro virtual de coordinación del conocimiento en VIH / Sida: experiencia de gestión del conocimiento en políticas en salud

Knowledge management helps to capture and disseminate existing knowledge, creating new knowledge, communication and collaboration between people who have it. Many organizations in Peru which are committed in the fight against HIV-AIDS have contributed to improving society's response to the epidemic; To do this, they have developed various activities and the way they have learned many lessons. However, these had not been systematized much less shared. Network Knowledge Management (RGC) in HIV-AIDS emerges as a community of practice composed of organizations and governmental and non-governmental seeking systematize their best practices effectively and efficiently achieving a collective learning about the achievements and failures in the topic of interest. These experiences are presented on the platform called "Virtual Knowledge Coordination Centre in HIV-AIDS (HIV CVCC)". The National Institute of Health (NIH) in order to meet one of its priorities and research agenda, results of the Concerted Health and contribute to the national policy of modernization of public administration Plan, assumes responsibility for the joint administration and management Peru AIDS Network RGC and HIV CVCC

Mimetisme et imitation : Une revue de la litterature

Ce travail propose une revue d.un ensemble de travaux sur la thematique de l'imitation. A partir d'une  discussion critique, l'objectif est de definir une nouvelle voie de recherche sur cette problematique et d'etablir la pertinence et la legitimite d.une telle recherche. En conclusion, la presente contribution propose une   nouvelle strategie de recherche theorique et empirique, dont l'objectif premier est d'exploiter les resultats et de combler certaines lacunes des travaux existants en matiere d.imitation.Mots cles : Imitation, theories de l'imitation, mimetisme

PCSK9, apolipoprotein E and lipoviral particles in chronic hepatitis C genotype 3: evidence for genotype-specific regulation of lipoprotein metabolism.

BACKGROUND & AIMS: Hepatitis C virus (HCV) associates with lipoproteins to form "lipoviral particles" (LVPs) that can facilitate viral entry into hepatocytes. Initial attachment occurs via heparan sulphate proteoglycans and low-density lipoprotein receptor (LDLR); CD81 then mediates a post-attachment event. Proprotein convertase subtilisin kexin type 9 (PCSK9) enhances the degradation of the LDLR and modulates liver CD81 levels. We measured LVP and PCSK9 in patients chronically infected with HCV genotype (G)3. PCSK9 concentrations were also measured in HCV-G1 to indirectly examine the role of LDLR in LVP clearance. METHODS: HCV RNA, LVP (d1.07g/ml) fractions, were quantified in patients with HCV-G3 (n=39) by real time RT-PCR and LVP ratios (LVPr; LVP/(LVP+non-LVP)) were calculated. Insulin resistance (IR) was assessed using the homeostasis model assessment of IR (HOMA-IR). Plasma PCSK9 concentrations were measured by ELISA in HCV-G3 and HCV-G1 (n=51). RESULTS: In HCV-G3 LVP load correlated inversely with HDL-C (r=-0.421; p=0.008), and apoE (r=-0.428; p=0.013). The LVPr varied more than 35-fold (median 0.286; range 0.027 to 0.969); PCSK9 was the strongest negative predictor of LVPr (R(2)=16.2%; p=0.012). HOMA-IR was not associated with LVP load or LVPr. PCSK9 concentrations were significantly lower in HCV-G3 compared to HCV-G1 (p<0.001). PCSK9 did not correlate with LDL-C in HCV-G3 or G1. CONCLUSIONS: The inverse correlation of LVP with apoE in HCV-G3, compared to the reverse in HCV-G1 suggests HCV genotype-specific differences in apoE mediated viral entry. Lower PCSK9 and LDL concentrations imply upregulated LDLR activity in HCV-G3