High-Order Harmonics from Bow Wave Caustics Driven by a High-Intensity Laser

<p>We propose a new mechanism of high-order harmonic generation during an interaction of a high-intensity laser pulse with underdense plasma. A tightly focused laser pulse creates a cavity in plasma pushing electrons aside and exciting the wake wave and the bow wave. At the joint of the cavity wall and the bow wave boundary, an annular spike of electron density is formed. This spike surrounds the cavity and moves together with the laser pulse. Collective motion of electrons in the spike driven by the laser field generates high-order harmonics. A strong localization of the electron spike, its robustness to oscillations imposed by the laser field and, consequently, its ability to produce high-order harmonics is explained by catastrophe theory. The proposed mechanism explains the experimental observations of high-order harmonics with the 9 TW J-KAREN laser (JAEA, Japan) and the 120 TW Astra Gemini laser (CLF RAL, UK) [A. S. Pirozhkov, et al., arXiv:1004.4514 (2010); A. S. Pirozhkov et al, AIP Proceedings, this volume]. The theory is corroborated by high-resolution two- and three-dimensional particle-in-cell simulations.p>

Genetic screening protocol for familial hypercholesterolemia which includes splicing defects gives an improved mutation detection rate

Familial hypercholesterolemia (FH) is a common single gene disorder, which predisposes to coronary artery disease. In a previous study, we have shown that in patients with definite FH around 20% had no identifiable gene defect after screening the entire exon coding area of the low density lipoprotein receptor (LDLR) and testing for the common Apolipoprotein B (ApoB) R3500Q mutation. In this study, we have extended the screen to additional families and have included the non-coding intron splice regions of the gene. In families with definite FH (tendon xanthoma present, n = 68) the improved genetic screening protocol increased the detection rate of mutations to 87%. This high detection rate greatly enhances the potential value of this test as part of a clinical screening program for FH. In contrast, the use of a limited screen in patients with possible FH (n = 130) resulted in a detection rate of 26%, but this is still of significant benefit in diagnosis of this genetic condition. We have also shown that 14% of LDLR defects are due to splice site mutations and that the most frequent splice mutation in our series (c.1845 + 11 c > g) is expressed at the RNA level. In addition, DNA samples from the patients in whom no LDLR or ApoB gene mutations were found, were sequenced for the NARC-1 gene. No mutations were identified which suggests that the role of NARC-1 in causing FH is minor. In a small proportion of families (

Removal of naphthenic acids from crude oil using amino acid ionic liquids

<p>A number of tetraalkylammonium and tetraalkylphosphonium amino acid based ionic liquids (AAILs) have been successfully used and recycled for the reactive extraction of naphthenic acids from crude oil and crude oil distillates. Spectral studies show that the mechanism by which this occurs is through the formation of a zwitterionic complex. Therein, the amino acid anion plays a key role in the formation of this complex. (C) 2013 Elsevier Ltd. All rights reserved.p>

Relative contributions of lipooligosaccharide inner and outer core modifications to nontypeable Haemophilus influenzae pathogenesis

<p>Nontypeable Haemophilus influenzae (NTHi) is a frequent commensal of the human nasopharynx that causes opportunistic infection in immunocompromised individuals. Existing evidence associates lipooligosaccharide (LOS) with disease, but the specific and relative contributions of NTHi LOS modifications to virulence properties of the bacterium have not been comprehensively addressed. Using NTHi strain 375, an isolate for which the detailed LOS structure has been determined, we compared systematically a set of isogenic mutant strains expressing sequentially truncated LOS. The relative contributions of 2-keto-3-deoxyoctulosonic acid, the triheptose inner core, oligosaccharide extensions on heptoses I and III, phosphorylcholine, digalactose, and sialic acid to NTHi resistance to antimicrobial peptides (AMP), self-aggregation, biofilm formation, cultured human respiratory epithelial infection, and murine pulmonary infection were assessed. We show that opsX, lgtF, lpsA, lic1, and lic2A contribute to bacterial resistance to AMP; lic1 is related to NTHi self-aggregation; lgtF, lic1, and siaB are involved in biofilm growth; opsX and lgtF participate in epithelial infection; and opsX, lgtF, and lpsA contribute to lung infection. Depending on the phenotype, the involvement of these LOS modifications occurs at different extents, independently or having an additive effect in combination. We discuss the relative contribution of LOS epitopes to NTHi virulence and frame a range of pathogenic traits in the context of infection.p>

BTLA mediates inhibition of human tumor-specific CD8+ T cells that can be partially reversed by vaccination.

The function of antigen-specific CD8+ T cells, which may protect against both infectious and malignant diseases, can be impaired by ligation of their inhibitory receptors, which include CTL-associated protein 4 (CTLA-4) and programmed cell death 1 (PD-1). Recently, B and T lymphocyte attenuator (BTLA) was identified as a novel inhibitory receptor with structural and functional similarities to CTLA-4 and PD-1. BTLA triggering leads to decreased antimicrobial and autoimmune T cell responses in mice, but its functions in humans are largely unknown. Here we have demonstrated that as human viral antigen-specific CD8+ T cells differentiated from naive to effector cells, their surface expression of BTLA was gradually downregulated. In marked contrast, human melanoma tumor antigen-specific effector CD8+ T cells persistently expressed high levels of BTLA in vivo and remained susceptible to functional inhibition by its ligand herpes virus entry mediator (HVEM). Such persistence of BTLA expression was also found in tumor antigen-specific CD8+ T cells from melanoma patients with spontaneous antitumor immune responses and after conventional peptide vaccination. Remarkably, addition of CpG oligodeoxynucleotides to the vaccine formulation led to progressive downregulation of BTLA in vivo and consequent resistance to BTLA-HVEM-mediated inhibition. Thus, BTLA activation inhibits the function of human CD8+ cancer-specific T cells, and appropriate immunotherapy may partially overcome this inhibition.

Incidencia de la política migratoria de España sobre los migrantes colombianos y su efecto en las relaciones diplomáticas binacionales. 2005-2010

El presente estudio de caso pretende explicar los mecanismos de respuesta que incorpora la política migratoria de España, específicamente la Ley Orgánica 4/2000. Este tipo de investigación permite observar el grado de incidencia entre las variables frente a las relaciones diplomáticas binacionales Colombia - España y tiene como objetivo analizar los mecanismos de respuesta de los migrantes colombianos frente a la política migratoria de España en el periodo 2005-2010. Se explican las acciones, proyectos y dimensiones de esta política migratoria y se analiza la posición de los migrantes colombianos frente a dicha política, que incide en aspectos relacionados con el empleo, la calidad de vida y la salud, mediante la teoría Push-Pull de Ernst Georg Ravenstein que permite establecer los mecanismos y las razones de aquellos que emigran. Finalmente, se determinan las acciones utilizadas por los grupos de presión que influyen en la articulación de las relaciones diplomáticas binacionales.

Cambios maculares y de capa de fibras nerviosas ganglionares posterior a la vitrectomía pars plana y sus factores pronósticos en la fundación oftalmológica nacional

OBJETIVOS: Determinar los factores pronóstico, cambios maculares morfológicos y de capa de fibras nerviosas ganglionares posterior a vitrectomía pars plana, en la Fundación Oftalmológica Nacional. MATERIALES Y MÉTODOS: Estudio longitudinal de antes y después (3y6 meses) de la vitrectomía pars plana (VPP) en pacientes con membrana epirretiniana, agujero macular, síndrome de tracción vítreo macular y opacidades vítreas no-inflamatorias. Se realizó seguimiento clínico y con tomografía de coherencia óptica. RESULTADOS: Grupo de 60 pacientes (mujeres 65.0%), edad promedio 65.45+9.49años y tiempo de enfermedad promedio 23+29.79meses. Las indicaciones de VPP (n=60ojos) fueron agujero macular (38.3%) y membrana epirretiniana (36.7%). Se encontró diferencia significativa entre grosor del complejo capa de células ganglionares (CCG)+capa plexiforme interna (CPI) inicial y 3 meses (p=0.039), correlación entre grosor del complejo CCG+CPI al tercer y sexto mes (r=0.704,p<0.001) y grosor del complejo CCG+CPI al tercer mes con grosor foveal central (CFT) al tercer y sexto mes (r=–0.594,p<0.001 y r=–0.595,p=0.001). Mayores de 65años tenían menor grosor de CFNG a 6meses (r=-0.528,p=0.007). El grosor de CFNG promedio y la presencia de la zona elipsoide inicial fueron factores pronósticos de buena agudeza visual al tercer mes de VPP (r2=0.414,p=0.018, y r2=0.414,p=0.010). CONCLUSIÓN: El grosor de CFNG y la presencia de la zona elipsoide inicial tienen alta capacidad predictiva de buena agudeza visual al tercer mes de VPP, y, correlación inversa entre grosor del complejo CCG+CPI con CFT al tercer y sexto mes de VPP.

Gene-nutrient interactions in the metabolic syndrome: single nucleotide polymorphisms in ADIPOQ and ADIPOR1 interact with plasma saturated fatty acids to modulate insulin resistance

Background: Progression of the metabolic syndrome (MetS) is determined by genetic and environmental factors. Gene-environment interactions may be important in modulating the susceptibility to the development of MetS traits. Objective: Gene-nutrient interactions were examined in MetS subjects to determine interactions between single nucleotide polymorphisms (SNPs) in the adiponectin gene (ADIPOQ) and its receptors (ADIPOR1 and ADIPOR2) and plasma fatty acid composition and their effects on MetS characteristics. Design: Plasma fatty acid composition, insulin sensitivity, plasma adiponectin and lipid concentrations, and ADIPOQ, ADIPOR1, and ADIPOR2 SNP genotypes were determined in a cross-sectional analysis of 451 subjects with the MetS who participated in the LIPGENE (Diet, Genomics, and the Metabolic Syndrome: an Integrated Nutrition, Agro-food, Social, and Economic Analysis) dietary intervention study and were repeated in 1754 subjects from the LIPGENE-SU.VI.MAX (SUpplementation en VItamines et Mineraux AntioXydants) case-control study (http://www.ucd.ie/lipgene). Results: Single SNP effects were detected in the cohort. Triacylglycerols, nonesterified fatty acids, and waist circumference were significantly different between genotypes for 2 SNPs (rs266729 in ADIPOQ and rs10920533 in ADIPOR1). Minor allele homozygotes for both of these SNPs were identified as having degrees of insulin resistance, as measured by the homeostasis model assessment of insulin resistance, that were highly responsive to differences in plasma saturated fatty acids (SFAs). The SFA-dependent association between ADIPOR1 rs10920533 and insulin resistance was replicated in cases with MetS from a separate independent study, which was an association not present in controls. Conclusions: A reduction in plasma SFAs could be expected to lower insulin resistance in MetS subjects who are minor allele carriers of rs266729 in ADIPOQ and rs10920533 in ADIPOR1. Personalized dietary advice to decrease SFA consumption in these individuals may be recommended as a possible therapeutic measure to improve insulin sensitivity. This trial was registered at clinicaltrials.

Períodos de interferência das plantas daninhas na cultura do algodoeiro (Gossypium hirsutum)

Com o objetivo de determinar os efeitos de períodos de controle e de convivência das plantas daninhas na produtividade da cultura do algodoeiro (Gossypium hirsutum), cultivar Delta-Opal, realizou-se um experimento que constou de dois grupos de tratamentos. No primeiro, a cultura permaneceu livre da competição das plantas daninhas desde a emergência até 7, 14, 21, 28, 35, 42, 49, 56, 63 dias e colheita (159 dias). No segundo, a cultura permaneceu em competição com a comunidade infestante desde a emergência até os mesmos períodos descritos para a primeira série de tratamentos. Dentre as espécies de plantas daninhas encontradas na área experimental, destacaram-se a tiririca (Cyperus rotundus), o fedegoso (Senna obtusifolia), a anileira (Indigofera hirsuta) e o capim-carrapicho (Cenchrus echinatus). Pelas condições edáficas, climáticas e florísticas sob as quais foi conduzida a cultura de algodão, o Período Anterior à Interferência (PAI) dessa comunidade que reduziu em 5% a produtividade da cultura foi de oito dias após a emergência da cultura (DAE); o Período Total de Prevenção da Interferência (PTPI) foi de 66 DAE; e o Período Crítico de Prevenção da Interferência (PCPI) foi dos 8 aos 66 DAE.

Composição florística da comunidade infestante em gramados de Paspalum notatum no município de Assis, SP

Os gramados de Paspalum notatum são os mais disseminados no Brasil, constituindo diferentes locais e propósitos. A infestação por plantas daninhas acarreta perda de qualidade estética quando a finalidade do gramado é ornamental. Com o objetivo de caracterizar a comunidade infestante em gramados de P. notatum no município de Assis/SP, foi realizado entre os meses de junho e julho de 2004 um levantamento florístico em áreas ensolaradas e sombreadas, sob copas de árvores. Cem amostras de 0,50 x 0,50 m foram coletadas nas duas condições de luminosidade (50 em áreas ensolaradas e 50 em áreas sombreadas), a partir das quais foram calculados os parâmetros freqüência, densidade, abundância, freqüência relativa, densidade relativa, abundância relativa e índice de valor de importância. Ao todo, foram identificadas 45 espécies de plantas daninhas, distribuídas em 15 famílias; Asteraceae apresentou o maior número de espécies nas condições ensolaradas e sombreadas. As espécies mais importantes nas áreas ensolaradas foram: Oxalis latifolia > Desmodium incanum > Cyperus flavus > Cyperus diffusus > Cyperus brevifolius; e nas áreas sombreadas: C. brevifolius > Alternanthera tenella > D. incanum > Elephantopus mollis > C. flavus. Para 80,0% das amostragens, a massa seca total da parte aérea das espécies de plantas daninhas não sofreu influência das condições ensolarada ou sombreada, constituindo uma produção máxima de aproximadamente 150 kg ha-1 para ambas as condições.

Search for Anomalous Wtb Couplings in Single Top Quark Production

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeitos cardiovasculares da anestesia dissociativa na reposição volêmica com colóide e solução hipertônica em cães: avaliação biotelemétrica

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)