Explorando la relación ser humano-naturaleza: agricultura urbana, ciencias de la conservación y ciudad

La tendencia dominante de las ciencias de la conservación y del urbanismo, ha buscado detener el deterioro ambiental estableciendo una base ética de actitudes consideradas apropiadas para conservar una naturaleza particular. A través del estudio de 9 jardines comunitarios parisinos, mostramos los límites que muestra esta aproximación al limitar la interacción ser humano-naturaleza. Tomando en cuenta subjetividades ciudadanas, brindamos perspectivas para nutrir las ciencias de la conservación y repensar las ciudades, en vista a alimentar la reflexión sobre el desafío global mayor que es la conservación de la naturaleza

Quantifying the Flexibility of Real-Time Systems

International audienceIn this paper we define the flexibility of a system as its capability to schedule a new task. We present an approach to quantify the flexibility of a system. More importantly, we show that it is possible under certain conditions to identify the task that will directly induce the limitations on a possible software update. If performed at design time, such a result can be used to adjust the system design by giving more slack to the limiting task. We illustrate how these results apply to a simple system

Antiretroviral Treatment Start-Time during Primary SIVmac Infection in Macaques Exerts a Different Impact on Early Viral Replication and Dissemination

BACKGROUND: The time of infection is rarely known in human cases; thus, the effects of delaying the initiation of antiretroviral therapy (ART) on the peripheral viral load and the establishment of viral reservoirs are poorly understood. METHODOLOGY/PRINCIPAL FINDINGS: Six groups of macaques, infected intravenously with SIV(mac251), were given placebo or antiretroviral therapy to explore reservoir establishment; macaques were treated for 2 weeks, with treatment starting 4 hours, 7 or 14 days after infection. Viral replication and dissemination were measured in the gut (rectum), in the lung and in blood and lymphoid tissues (peripheral lymph nodes), by quantifying viral RNA, DNA and 2LTR circles. We used immunohistochemistry (CD4 and CD68) to assess the impact of these treatments on the relative amount of virus target cells in tissue. Treatment that was started 4 hours post-infection (pi) decreased viral replication and dissemination in blood and tissue samples, which were assessed on day 14 (RNA/DNA/2LTR circles). The virus remained detectable and lymphoid tissues were activated in LN and the gut in both placebo- and ART-treated animals. Viral RNA in plasma continued to be lower in macaques treated seven days after infection; however, this was not the case for viral DNA in peripheral blood mononuclear cells. There was a small but significant difference in RNA and DNA levels in tissues between placebo- and ART-treated animals on day 21. When started 14 days after infection, treatment resulted in a limited decrease in the plasma viral load. CONCLUSIONS: Treatment that was started 4 hours after infection significantly reduced viral replication and dissemination. When started 7 days after infection, it was of slight virological benefit in peripheral blood and in tissues, and treatment was even less effective if started 14 days pi. These data favor starting ART no longer than one week after intravenous SIV(mac251) exposure

Identification of glucocorticoid-induced leucine zipper as a key regulator of tumor cell proliferation in epithelial ovarian cancer

<p>Abstract</p> <p>Background</p> <p>Little is known about the molecules that contribute to tumor progression of epithelial ovarian cancer (EOC), currently a leading cause of mortality from gynecological malignancies. Glucocorticoid-Induced Leucine Zipper (GILZ), an intracellular protein widely expressed in immune tissues, has been reported in epithelial tissues and controls some of key signaling pathways involved in tumorigenesis. However, there has been no report on GILZ in EOC up to now. The objectives of the current study were to examine the expression of GILZ in EOC and its effect on tumor cell proliferation.</p> <p>Results</p> <p>GILZ expression was measured by immunohistochemical staining in tissue sections from 3 normal ovaries, 7 benign EOC and 50 invasive EOC. GILZ was not detected on the surface epithelium of normal ovaries and benign tumors. In contrast, it was expressed in the cytoplasm of tumor cells in 80% EOC specimens. GILZ immunostaining scores correlated positively to the proliferation marker Ki-67 (Spearman test in univariate analysis, <it>P </it>< 0.00001, r = 0.56). They were also higher in tumor cells containing large amounts of phosphorylated protein kinase B (p-AKT) (unpaired t test, <it>P </it>< 0.0001). To assess the effect of GILZ on proliferation and AKT activation, we used the BG-1 cell line derived from ovarian tumor cells as a cellular model. GILZ expression was either enhanced by stable transfection or decreased by the use of small interfering (si) RNA targeting GILZ. We found that GILZ increased cell proliferation, phospho-AKT cellular content and AKT kinase activity. Further, GILZ upregulated cyclin D1 and phosphorylated retinoblastoma (p-Rb), downregulated cyclin-dependent kinase inhibitor p21, and promoted the entry into S phase of cell cycle.</p> <p>Conclusion</p> <p>The present study is the first to identify GILZ as a molecule produced by ovarian cancer cells that promotes cell cycle progression and proliferation. Our findings clearly indicate that GILZ activates AKT, a crucial signaling molecule in tumorigenesis. GILZ thus appears as a potential key molecule in EOC.</p

CXCL12 expression by healthy and malignant ovarian epithelial cells

<p>Abstract</p> <p>Background</p> <p>CXCL12 has been widely reported to play a biologically relevant role in tumor growth and spread. In epithelial ovarian cancer (EOC), CXCL12 enhances tumor angiogenesis and contributes to the immunosuppressive network. However, its prognostic significance remains unclear. We thus compared CXCL12 status in healthy and malignant ovaries, to assess its prognostic value.</p> <p>Methods</p> <p>Immunohistochemistry was used to analyze CXCL12 expression in the reproductive tracts, including the ovaries and fallopian tubes, of healthy women, in benign and borderline epithelial tumors, and in a series of 183 tumor specimens from patients with advanced primary EOC enrolled in a multicenter prospective clinical trial of paclitaxel/carboplatin/gemcitabine-based chemotherapy (GINECO study). Univariate COX model analysis was performed to assess the prognostic value of clinical and biological variables. Kaplan-Meier methods were used to generate progression-free and overall survival curves.</p> <p>Results</p> <p>Epithelial cells from the surface of the ovary and the fallopian tubes stained positive for CXCL12, whereas the follicles within the ovary did not. Epithelial cells in benign, borderline and malignant tumors also expressed CXCL12. In EOC specimens, CXCL12 immunoreactivity was observed mostly in epithelial tumor cells. The intensity of the signal obtained ranged from strong in 86 cases (47%) to absent in 18 cases (<10%). This uneven distribution of CXCL12 did not reflect the morphological heterogeneity of EOC. CXCL12 expression levels were not correlated with any of the clinical parameters currently used to determine EOC prognosis or with HER2 status. They also had no impact on progression-free or overall survival.</p> <p>Conclusion</p> <p>Our findings highlight the previously unappreciated constitutive expression of CXCL12 on healthy epithelia of the ovary surface and fallopian tubes, indicating that EOC may originate from either of these epithelia. We reveal that CXCL12 production by malignant epithelial cells precedes tumorigenesis and we confirm in a large cohort of patients with advanced EOC that CXCL12 expression level in EOC is not a valuable prognostic factor in itself.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00052468">NCT00052468</a></p

Small but powerful: The importance of French community gardens for residents

International audienc

Specificities of French community gardens as environmental stewardships

Community-based efforts are essential to address urban social-ecological challenges. Here, we focus on French community gardens. Through participant observation and semistructured interviews, this study seeks to provide empirical evidence on: (1) what motivates volunteer gardeners in French community gardens to undertake this activity, (2) what practices take place in the gardens, and (3) which individual and collective processes are associated with gardeners' experiences in the gardens. Through these questions, we aim to understand how these initiatives relate to environmental stewardship. Our results show that environmental, social, and self-motivations are the drivers behind gardeners' participation in the gardens. It seems that involvement in the gardens provides opportunities to fulfill those needs and/or motives through different interrelated processes between the individual with him/herself, the human collective, and nature such as: contemplating nature and benefiting from sensory experiences, having access to environmental education, experiencing individual and collective organization, renewing social-ecological relationships, and facing local challenges. We note that French community gardens provide arenas for new experiences of nature. In addition, even if gardens' biophysical features and gardening practices allow a series of processes that provide social and ecological benefits and outcomes, these gardens refer to environmental stewardship practices by cultivating relational values. These values provide opportunities for innovative ways of creative conservation, reflecting how care for ourselves extends to care for others, for places, and for nature

Explorando la relación ser humano-naturaleza: agricultura urbana, ciencias de la conservación y ciudad

In this article we present how human-nature duality has been the epistemological and ontological base of environmental sciences. Then, we show how the French initiatives of community gardens in spite of been anchored on this human-nature separation, constitute an opportunity to (re)build news relationships toward nature(s) and the city; allowing a new environmental sciences epistemic reflection. We base our argument on thirty interviews of gardeners realized between October 2013 and September 2014 in twelve community gardens in Paris and its suburbs. Also, we realized a file study in various locals associations involved in this activity. La tendencia dominante de las ciencias de la conservación y del urbanismo, ha buscado detener el deterioro ambiental estableciendo una base ética de actitudes consideradas apropiadas para conservar una naturaleza particular. A través del estudio de 9 jardines comunitarios parisinos, mostramos los límites que muestra esta aproximación al limitar la interacción ser humano-naturaleza. Tomando en cuenta subjetividades ciudadanas, brindamos perspectivas para nutrir las ciencias de la conservación y repensar las ciudades, en vista a alimentar la reflexión sobre el desafío global mayor que es la conservación de la naturaleza.

Improving and Estimating the Precision of Bounds on the Worst-Case Latency of Task Chains

Special Issue of the EMSOFT 2018 International ConferenceInternational audienceOne major issue that hinders the use of performance analysis in industrial design processes is the pessimism inherent to any analysis technique that applies to realistic system models. Indeed, such analyses may conservatively declare unschedulable systems that will in fact never miss any deadlines. We advocate the need to compute not only tight upper bounds on worst-case behaviors, but also tight lower bounds. As a first step, we focus on uniprocessor systems executing a set of sporadic or periodic hard real-time task chains. Each task has its own priority, and the chains are scheduled according to the fixed-priority preemptive scheduling policy. Computing the worst-case end-to-end latency (WCEL) of each chain is complex because of the intricate relationship between the task priorities. Compared to the state of the art, our analysis provides upper bounds on the WCEL in the more general case of asynchro-nous task chains, and also provides lower bounds on the WCEL both for synchronous and asynchronous chains. Our computed lower bounds correspond to actual system executions exhibiting a behavior that is as close to the worst case as possible, while all other approaches rely on simulations. Extensive experiments show the relevance of lower bounds on the worst-case behavior for the industrial design of real-time embedded systems. CCS CONCEPTS • Computer systems organization → Embedded systems; KEYWORDS Worst-case end to end latency, Latency analysis, Task chains ACM Reference format

Calibration of a coupled canopy functioning and SVAT model in the ReSeDA experiment. Towards the assimilation of SPOT/HRV observations into the model

In the framework of the Alpilles-ReSeDA experiment [12], a coupled canopy functioning and SVAT model was used to simulate wheat crops. Each sub-model was first initialized and calibrated separately, using literature and ground measurements. The model was then run in coupled mode and gave reasonable results in terms of vegetation model outputs. The results were less satisfactory for the SVAT outputs. As a conclusion we pointed out that the SPOT/HRV measurements could be used through a calibration procedure to retrieve some of the growth model key parameters.Calage d'un modèle couplé de fonctionnement du couvert et de SVAT dans l'expérience ReSeDA. Vers l'intégration des observations SPOT/HRV dans le modèle. Dans le cadre de l'expérimentation Alpilles-ReSeDA, un modèle couplé de fonctionnement du couvert et de SVAT a été utilisé pour simuler les cultures de blé. Chaque sous-modèle a été tout d'abord initialisé et calé séparément en utilisant les données de la littérature et les mesures au sol. Le modèle a ensuite été utilisé en mode couplé et a donné des résultats raisonnables en terme de sortie de modèle de végétation. Les résultats ont été moins satisfaisants pour les sorties du modèle SVAT. En conclusion, nous avons mis en évidence que les mesures SPOT/HRV peuvent être utilisées à travers une procédure de calage pour fournir un certain nombre de paramètres-clés des modèles de croissance