Quantum bounds for gravitational de Sitter entropy and the Cardy-Verlinde formula

We analyze different types of quantum corrections to the Cardy-Verlinde entropy formula in a Friedmann-Robertson-Walker universe and in an (anti)-de Sitter space. In all cases we show that quantum corrections can be represented by an effective cosmological constant which is then used to redefine the parameters entering the Cardy-Verlinde formula so that it becomes valid also with quantum corrections, a fact that we interpret as a further indication of its universality. A proposed relation between Cardy-Verlinde formula and the ADM Hamiltonian constraint is given.Comment: LaTeX file, 15 pages, reference is adde

Fortaleciendo los sistemas tradicionales de producción de semilla en los Andes en Perú.

Los cultivos alimenticios en el Perú han estado históricamente asociados a la pequeña agricultura andina, caracterizada por predios muy pequeños (<3ha), tecnificación tradicional y producción destinada principalmente al autoconsumo y una pequeña proporción para la venta y producción de semilla. El Centro Internacional de la Papa (CIP) a través de su programa Papa Andina/INCOPA promovió una serie de innovaciones que han permitido revalorizar la biodiversidad de la papa y organizar cadenas productivas inclusivas para articular a pequeños productores pobres alto andinos a nuevos mercados. Sin embargo, esta innovación generó demanda por semilla de variedades nativas con potencial de mercado, la cual no ha podido ser satisfecha debido a que el sistema formal de semilla no abastece la demanda interna y las variedades nativas no han sido priorizadas por dicho sistema. Como alternativa, los proyectos del CIP como InnovAndes (Junín y Huancavelica) y McKnight (Pasco), están promoviendo esquemas no convencionales como una alternativa flexible para mejorar los sistemas tradicionales de producción de semilla y responder a la demanda de los pequeños productores. En ambos casos, en las comunidades participantes se organizaron comités de gestión de semillas, que fueron capacitados en técnicas de multiplicación de semilla e identificación de plagas para tener a su cargo la producción de semilla básica en campos semilleros e invernaderos empleando la técnica de selección positiva. La capacitación se realizó a través de escuelas de campo de agricultores (ECA) semilleristas. Como resultado de la intervención, del Proyecto McKnight en las comunidades de La Quinua y Quichas (Pasco) se logró reducir en más del 92% la incidencia de virus (PVX y PVS), enfermedades (P. infestans) e insectos (Epitrix spp, y Diabrótica spp) que afectan la calidad de la semilla, lográndose aumentar el rendimiento promedio de tubérculos en 53%. En este proyecto, el comité de gestión de semillas se constituyó como empresa y cuentan con un invernadero de aeroponia para producir semilla prebásicaa bajo costo, habiendo producido hasta la fecha 54,000 tuberculillos de 6 variedades nativas. En el marco del proyecto Innovandes, los productores de Chicche y Pomamanta (Junín) aprendieron la técnica convencional de propagación y multiplicación de semilla pre-básica en sus respectivos invernaderos. En 2011 la producción fue en total 20,574 tuberculillos de variedades nativas con demanda en el mercado, con lo que han constituido un fondo rotatorio de semilla de las variedades Leona y Cceccorani de uso en gastronomía y la industria, respectivamente. Los resultados indican que la producción de semilla pre-básica en combinación con la técnica de selección positiva ayudará a gestar un mercado regional de semilla de calidad, con posibilidades de evolucionar hacia un esquema o modelo no convencional, similar al de semilla de calidad declarada (QDS)

Identificação de um polimorfismo de única base no gene rap-1 de Babesia bovis.

Babesia bovis provoca um grave quadro de anemia hemolítica em bovinos, resultando em grandes prejuízos devido à mortalidade, abortos, redução de fertilidade e queda da produção de carne e leite. O gene RAP-1 (Rhoptry-associated protein)1 de Babesia bovis codifica uma proteína de 60 KDa, que é reconhecida por anticorpos e linfócitos T de bovinos. O objetivo deste trabalho foi verificar a presença de polimorfismos no gene RAP-1 de Babesia bovis amplificado de material proveniente de búfalos infectados. Parte do gene RAP-1 de B. bovis foi amplificado por Nested-PCR. Foram sequenciadas amostras de quatro búfalos e de um bovino para que se pudesse comparar as sequências obtidas nestas espécies. As reações de seqüenciamento foram realizadas utilizando o Kit ABI PRISM® Big Dye terminator v. 3.1 cycle sequencing da Applied Biosystem. Os eletroferogramas gerados pelo seqüenciador ABI 3100 foram submetidos à análise de qualidade pelo programa Phred, que atribui um valor de qualidade a cada nucleotídeo identificado. Em seguida, foram submetidos ao programa de montagem Phrap que agrupa as sequências organizando-as em contigs. A visualização das sequências geradas e, conseqüentemente, dos SNPs foi realizada através do programa Consed. Não foi encontrada diferença entre a sequência de B. bovis isolada de bovino e as dos isolados de búfalos, no entanto, em relação à sequência depositada no banco de dados NCBI (http://www.ncbi.nlm.nih.gov/), foi encontrado um polimorfismo de única base (SNP) G/A no nucleotídeo 688. Verificou-se que este polimorfismo também estava presente na amostra obtida de bovino, pois o segmento do gene RAP-1 do isolado de bovino apresentou genótipo heterozigoto AG . Três isolados de búfalos também apresentaram o genótipo AG para este polimorfismo. O SNP identificado neste trabalho não está depositado no NCBI

Soluble tumor necrosis factor receptor 1 and 2 predict outcomes in advanced chronic kidney disease : a prospective cohort study

Background : Soluble tumor necrosis factor receptors 1 (sTNFR1) and 2 (sTNFR2) have been associated to progression of renal failure, end stage renal disease and mortality in early stages of chronic kidney disease (CKD), mostly in the context of diabetic nephropathy. The predictive value of these markers in advanced stages of CKD irrespective of the specific causes of kidney disease has not yet been defined. In this study, the relationship between sTNFR1 and sTNFR2 and the risk for adverse cardiovascular events (CVE) and all-cause mortality was investigated in a population with CKD stage 4-5, not yet on dialysis, to minimize the confounding by renal function. Patients and methods : In 131 patients, CKD stage 4-5, sTNFR1, sTNFR2 were analysed for their association to a composite endpoint of all-cause mortality or first non-fatal CVE by univariate and multivariate Cox proportional hazards models. In the multivariate models, age, gender, CRP, eGFR and significant comorbidities were included as covariates. Results : During a median follow-up of 33 months, 40 events (30.5%) occurred of which 29 deaths (22.1%) and 11 (8.4%) first non-fatal CVE. In univariate analysis, the hazard ratios (HR) of sTNFR1 and sTNFR2 for negative outcome were 1.49 (95% confidence interval (CI): 1.28-1.75) and 1.13 (95% CI: 1.06-1.20) respectively. After adjustment for clinical covariables (age, CRP, diabetes and a history of cardiovascular disease) both sTNFRs remained independently associated to outcomes (HR: sTNFR1: 1.51, 95% CI: 1.30-1.77; sTNFR2: 1.13, 95% CI: 1.06-1.20). A subanalysis of the non-diabetic patients in the study population confirmed these findings, especially for sTNFR1. Conclusion : sTNFR1 and sTNFR2 are independently associated to all-cause mortality or an increased risk for cardiovascular events in advanced CKD irrespective of the cause of kidney disease

(Non)-singular brane-world cosmology induced by quantum effects in d5 dilatonic gravity

5d dilatonic gravity (bosonic sector of gauged supergravity) with non-trivial bulk potential and with surface terms (boundary cosmological constant and trace anomaly induced effective action for brane quantum matter) is considered. For constant bulk potential and maximally SUSY Yang-Mills theory (CFT living on the brane) the inflationary brane-world is constructed. The bulk is singular asymptotically AdS space with non-constant dilaton and dilatonic de Sitter or hyperbolic brane is induced by quantum matter effects. At the same time, dilaton on the brane is determined dynamically. This all is natural realization of warped compactification in AdS/CFT correspondence. For fine-tuned toy example of non-constant bulk potential we found the non-singular dilatonic brane-world where bulk again represents asymptotically AdS space and de Sitter brane (inflationary phase of observable Universe) is induced exclusively by quantum effects. The radius of the brane and dilaton are determined dynamically. The analytically solvable example of exponential bulk potential leading to singular asymptotically AdS dilatonic bulk space with de Sitter (or hyperbolic) brane is also presented.In all cases under discussion the gravity on the brane is trapped via Randall-Sundrum scenario. It is shown that qualitatively the same types of brane-worlds occur when quantum brane matter is described by $N$ dilaton coupled spinors.Comment: LaTeX file 28 pages and two eps files, few misprints are correcte

Anti-de Sitter black holes, perfect fluids, and holography

We consider asymptotically anti-de Sitter black holes in $d$-spacetime dimensions in the thermodynamically stable regime. We show that the Bekenstein-Hawking entropy and its leading order corrections due to thermal fluctuations can be reproduced by a weakly interacting fluid of bosons and fermions (`dual gas') in $\Delta=\alpha(d-2)+1$ spacetime dimensions, where the energy-momentum dispersion relation for the constituents of the fluid is assumed to be $\epsilon = \kappa p^\alpha$. We examine implications of this result for entropy bounds and the holographic hypothesis.Comment: Minor changes to match published version. 9 Pages, Revte

String versus Einstein frame in an AdS/CFT induced quantum dilatonic brane-world universe

AdS/CFT induced quantum dilatonic brane-world where 4d boundary is flat or de Sitter (inflationary) or Anti-de Sitter brane is considered. The classical brane tension is fixed but boundary QFT produces the effective brane tension via the account of corresponding conformal anomaly induced effective action. This results in inducing of brane-worlds in accordance with AdS/CFT set-up as warped compactification. The explicit, independent construction of quantum induced dilatonic brane-worlds in two frames: string and Einstein one is done. It is demonstrated their complete equivalency for all quantum cosmological brane-worlds under discussion, including several examples of classical brane-world black holes. This is different from quantum corrected 4d dilatonic gravity where de Sitter solution exists in Einstein but not in Jordan (string) frame. The role of quantum corrections on massive graviton perturbations around Anti-de Sitter brane is briefly discussed.Comment: LaTeX file, 24 pages, minor changes to match with published versio

Macrophages Are Required for Dendritic Cell Uptake of Respiratory Syncytial Virus from an Infected Epithelium

We have previously shown that the respiratory syncytial virus [RSV] can productively infect monocyte derived dendritic cells [MoDC] and remain dormant within the same cells for prolonged periods. It is therefore possible that infected dendritic cells act as a reservoir within the airways of individuals between annual epidemics. In the present study we explored the possibility that sub-epithelial DCs can be infected with RSV from differentiated bronchial epithelium and that in turn RSV from DCs can infect the epithelium. A dual co-culture model was established in which a differentiated primary airway epithelium on an Air Liquid Interface (ALI) was cultured on a transwell insert and MoDCs were subsequently added to the basolateral membrane of the insert. Further experiments were undertaken using a triple co-culture model in which in which macrophages were added to the apical surface of the differentiated epithelium. A modified RSV [rr-RSV] expressing a red fluorescent protein marker of replication was used to infect either the MoDCs or the differentiated epithelium and infection of the reciprocal cell type was assessed using confocal microscopy. Our data shows that primary epithelium became infected when rr-RSV infected MoDCs were introduced onto the basal surface of the transwell insert. MoDCs located beneath the epithelium did not become infected with virus from infected epithelial cells in the dual co-culture model. However when macrophages were present on the apical surface of the primary epithelium infection of the basal MoDCs occurred. Our data suggests that RSV infected dendritic cells readily transmit infection to epithelial cells even when they are located beneath the basal layer. However macrophages appear to be necessary for the transmission of infection from epithelial cells to basal dendritic cells

Accuracy of CT Colonography for Detection of Large Adenomas and Cancers

Background Computed tomographic (CT) colonography is a noninvasive option in screening for colorectal cancer. However, its accuracy as a screening tool in asymptomatic adults has not been well defined. Methods We recruited 2600 asymptomatic study participants, 50 years of age or older, at 15 study centers. CT colonographic images were acquired with the use of standard bowel preparation, stool and fluid tagging, mechanical insufflation, and multidetector-row CT scanners (with 16 or more rows). Radiologists trained in CT colonography reported all lesions measuring 5 mm or more in diameter. Optical colonoscopy and histologic review were performed according to established clinical protocols at each center and served as the reference standard. The primary end point was detection by CT colonography of histologically confirmed large adenomas and adenocarcinomas (10 mm in diameter or larger) that had been detected by colonoscopy; detection of smaller colorectal lesions (6 to 9 mm in diameter) was also evaluated. Results Complete data were available for 2531 participants (97%). For large adenomas and cancers, the mean (±SE) per-patient estimates of the sensitivity, specificity, positive and negative predictive values, and area under the receiver-operating-characteristic curve for CT colonography were 0.90±0.03, 0.86±0.02, 0.23±0.02, 0.99± Conclusions In this study of asymptomatic adults, CT colonographic screening identified 90% of subjects with adenomas or cancers measuring 10 mm or more in diameter. These findings augment published data on the role of CT colonography in screening patients with an average risk of colorectal cancer. (ClinicalTrials.gov number, NCT00084929; American College of Radiology Imaging Network [ACRIN] number, 6664.

Ginsenoside-Rb1 Inhibition of VEGF Release – Structure and Activity Relations (SAR) Perspective

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