Stochastic Bounds For The Mean Characteristics Of An M/G/l Queue With General Retrial Times

The main goal of this paper is to investigate various monotonicity properties of a single server retrial queue with a first-come-first-served (FCFS) orbit and general retrial times using the stochastic order relations (strong stochastic (≤st), increasing convex (≤icx), and Laplace ordering (≤ L)) in order to derive performance indices bounds

Optimal bandwidth matrices in functional principal component analysis of density functions

In order to explore and compare a finite number T of data sets by applying functional principal component analysis (FPCA) to the T associated probability density functions, we estimate these density functions by using the multivariate kernel method. The data set sizes being fixed, we study the behaviour of this FPCA under the assumption that all the bandwidth matrices used in the estimation of densities are proportional to a common parameter h and proportional to either the variance matrices or the identity matrix. In this context, we propose a selection criterion of the parameter h which depends only on the data and the FPCA method. Then, on simulated examples, we compare the quality of approximation of the FPCA when the bandwidth matrices are selected using either the previous criterion or two other classical bandwidth selection methods, that is, a plug-in or a cross-validation method

LEÓN, JOSÉ CLAUDIO DE Y SRA. [Material gráfico]

Copia digital. Madrid : Ministerio de Educación, Cultura y Deporte, 201

African Mitochondrial DNA Haplogroup L2 Is Associated with Slower Decline of β-cell Function and Lower Incidence of Diabetes Mellitus in Non-Hispanic, Black Women Living with Human Immunodeficiency Virus

Background: Susceptibility to metabolic diseases may be influenced by mitochondrial genetic variability among people living with human immunodeficiency virus (HIV; PLWH), but remains unexplored in populations with African ancestry. We investigated the association between mitochondrial DNA (mtDNA) haplogroups and the homeostatic model assessments of β-cell function (HOMA-B) and insulin resistance (HOMA-IR), as well as incident diabetes mellitus (DM), among Black women living with or at risk for HIV. Methods: Women without DM who had fasting glucose (FG) and insulin (FI) data for ≥2 visits were included. Haplogroups were inferred from genotyping data using HaploGrep. HOMA-B and HOMA-IR were calculated using FG and FI data. Incident DM was defined by a combination of FG ≥ 126 mg/dL, the use of DM medication, a DM diagnosis, or hemoglobin A1c ≥ 6.5%. We compared HOMA-B, HOMA-IR, and incident DM by haplogroups and assessed the associations between HOMA-B and HOMA-IR and DM by haplogroup. Results: Of 1288 women (933 living with HIV and 355 living without HIV), PLWH had higher initial HOMA-B and HOMA-IR than people living without HIV. PLWH with haplogroup L2 had a slower decline in HOMA-B per year (Pinteraction =. 02) and a lower risk of incident DM (hazard ratio [HR], 0.51; 95% confidence interval [CI],. 32-.82) than PLWH with other haplogroups after adjustments for age, body mass index, combination antiretroviral therapy use, CD4 cell counts, and HIV RNA. The impact of HOMA-IR on incident DM was less significant in those with haplogroup L2, compared to non-L2 (HR, 1.28 [95% CI,. 70-2.38] vs 4.13 [95% CI, 3.28-5.22], respectively; Pinteraction <. 01), among PLWH. Conclusions: Mitochondrial genetic variation is associated with β-cell functions and incident DM in non-Hispanic, Black women with HIV and alters the relationship between insulin resistance and DM

Interleukin-10 (IL-10) Pathway: Genetic Variants and Outcomes of HIV-1 Infection in African American Adolescents

promoter sequence have been reported to influence pathogenesis or acquisition of HIV-1 infection. T-cell increased by 31±0.9% and 17±8% every 3 months for AA and AG genotype, respectively. gene family to HIV-1/AIDS

Association between Regulator of G Protein Signaling 9–2 and Body Weight

Regulator of G protein signaling 9–2 (RGS9–2) is a protein that is highly enriched in the striatum, a brain region that mediates motivation, movement and reward responses. We identified a naturally occurring 5 nucleotide deletion polymorphism in the human RGS9 gene and found that the mean body mass index (BMI) of individuals with the deletion was significantly higher than those without. A splicing reporter minigene assay demonstrated that the deletion had the potential to significantly decrease the levels of correctly spliced RGS9 gene product. We measured the weights of rats after virally transduced overexpression of RGS9–2 or the structurally related RGS proteins, RGS7, or RGS11, in the nucleus accumbens (NAc) and observed a reduction in body weight after overexpression of RGS9–2 but not RGS7 or 11. Conversely, we found that the RGS9 knockout mice were heavier than their wild-type littermates and had significantly higher percentages of abdominal fat. The constituent adipocytes were found to have a mean cross-sectional area that was more than double that of corresponding cells from wild-type mice. However, food intake and locomotion were not significantly different between the two strains. These studies with humans, rats and mice implicate RGS9–2 as a factor in regulating body weight.National Institute of Mental Health (U.S.) (R41MH78570 award)National Center for Research Resources (U.S.) (Rhode Island IDeA Network of Biomedical Research Excellence (RI-INBRE) Award P20RR016457-10

Modeles de Risque et Files d’Attente: La methode de stabilite forte

Abstract. One of the problems which appear during comprehension and working of the complex systems is the analysis of the stability of their functioning. These last years, the specialists became aware of the importance of the stability analysis in actuarial sciences and in financial mathematics. In this work, we are interested in the applicationof the strong stability method in queueing systems and in risk models. We clarify the conditions of equivalence and translation of results between models of these two theories.Resume. L’un des probl`emes qui apparaissent lors de la conception et de l’exploitation des syst`emes complexes est l’analyse de la stabilit´e de leur fonctionnement. Ces derni`eres ann´ees, les sp´ecialistes ont pris conscience de l’importance de l’analyse de stabilit´e dans les probl`emes en actuariat et en math´ematiques financi`eres. Dans ce travail, nous nousint´eressons `a l’application de la m´ethode de stabilit´e forte dans les files d’attente et les mod`eles de risque. Nous  clarifions ainsi les conditions d’´equivalence et de translation de r´esultats entre la th´eorie de risque et celle des files d’attente. Key words: Risk models, Ruin probabilities, Queueing systems, Interaction risk and queueing theories, Strong stability,Continuity estimates