On the analysis of a dynamical model representing gene regulatory networks under negative feedback

Cataloged from PDF version of article.In this work, stability analysis is performed for a cyclic dynamical model of gene regulatory networks involving time delays, under negative feedback. The model considered has nonlinearities with negative Schwarzian derivatives. Sufficient conditions implying global stability of these types of GRNs are obtained. The special case of homogenous gene regulatory networks is also studied; in this case, the proposed stability conditions depend only on the parameters of the nonlinearity function. Illustrative numerical examples complete the presentation.Copyright (c) 2013 John Wiley & Sons, Ltd

Capacitating Community: The Writing Innovation Symposium

The topic of this symposium, capacitating community, invites CLJ readers to consider what makes a community possible. This piece showcases one means, small conferences, via a retrospective on the Writing Innovation Symposium (WIS), a regional event with national scope that has hosted writers and writing educators annually in Milwaukee, WI, since 2018. Through a quilted conversation pieced from hours of small-group discussion, twenty-nine participants across academic and nonacademic ranks, roles, and ranges of experience offer insight into the WIS as well as the nature and value of professional community

Análisis de los principales factores externos e internos que influyen en la reparación de la planeacion tributaria por parte de las pequeñas y mediana empresas en colombia

En este trabajo se encontrara las diferentes alternativas que puede tomar un contribuyente o responsable para la elaboración de una planeacion tributaria, teniendo en cuenta los factores tanto internos como externos que afecta directamente a su negocio; basándose todo en marco legal con el fin de liquidar el impuesto estrictamente necesario y que se vea reflejado en la distribución de utilidades en cabeza de los socios. También se explica los diferentes efectos que se tienen el flujo de caja dependiendo de las políticas económicas y financieras, de la cultura tributaria que tenga implantada la empresa y si tiene fijados objetivos a corto o largo plazo

Capacitating Community: The Writing Innovation Symposium

The topic of this symposium, capacitating community, invites CLJ readers to consider what makes a community possible. This piece showcases one means, small conferences, via a retrospective on the Writing Innovation Symposium (WIS), a regional event with national scope that has hosted writers and writing educators annually in Milwaukee, WI, since 2018. Through a quilted conversation pieced from hours of small-group discussion, twenty-nine participants across academic and nonacademic ranks, roles, and ranges of experience offer insight into the WIS as well as the nature and value of professional community

Analysis of Gene Regulatory Networks under Positive Feedback

International audienc

Vitamin D3 Supplementation Increases Spine Bone Mineral Density in Adolescents and Young Adults With Human Immunodeficiency Virus Infection Being Treated With Tenofovir Disoproxil Fumarate: A Randomized, Placebo-Controlled Trial

BackgroundTenofovir disoproxil fumarate (TDF) decreases bone mineral density (BMD). We hypothesized that vitamin D3 (VITD3) would increase BMD in youth receiving TDF.MethodsThis was a randomized, double-blind, placebo-controlled trial of directly observed VITD3 vs placebo every 4 weeks for 48 weeks in youth aged 16-24 years with HIV, RNA load <200 copies/mL, taking TDF-containing combination antiretroviral therapy (TDF-cART) for ≥180 days. Participants (N = 214) received a daily multivitamin containing VITD3 400 IU and calcium 162 mg, plus monthly randomized VITD3 50000 IU (n = 109) or placebo (n = 105). Outcome was change from baseline to week 48 in lumbar spine BMD (LSBMD). Data presented are median (Q1, Q3).ResultsParticipants were aged 22.0 (21.0, 23.0) years, 84% were male, and 74% were black/African American. At baseline, 62% had 25-hydroxy vitamin D (25-OHD) <20 ng/mL. Multivitamin adherence was 49% (29%, 69%), and VITD3/placebo adherence 100% (100%, 100%). Vitamin D intake was 2020 (1914, 2168) and 284 (179, 394) IU/day, and serum 25-OHD concentration was 36.9 (30.5, 42.4) and 20.6 (14.4, 25.8) ng/mL at 48 weeks in VITD3 and placebo groups, respectively (P < .001). From baseline to week 48, LSBMD increased by 1.15% (-0.75% to 2.74%) in the VITD3 group (n = 99; P < .001) and 0.09% (-1.49% to 2.61%) in the placebo group (n = 89; P = .25), without between-group difference (P = .12). VITD3 group changes occurred with baseline 25-OHD <20 ng/mL (1.17% [-.82% to 2.90%]; P = .004) and ≥20 ng/mL (0.93% [-.26% to 2.15%]; P = .033).ConclusionsFor youth taking TDF-cART, LSBMD increased through 48 weeks with VITD3 plus multivitamin, but not with placebo plus multivitamin, independent of baseline vitamin D status.Clinical trials registrationNCT01751646