Etude du cycle nycthéméral de la teneur en oxygène dissous en bassins de pisciculture par la méthode des moyennes mobiles. Relation avec la température et l'insolation

Dans ce travail, le cycle journalier de l'oxygène dissous en bassins de pisciculture semi-intensive a été étudié en relation avec des données météorologiques. Nous disposions pour cela de 22 semaines d'enregistrements (mesures horaires) de janvier 1988 à décembre 1989, dont une semaine de mesures sous glace. Chaque période de mesures a été traitée comme une série chronologique en pratiquant une décomposition saisonnière par la méthode des moyennes mobiles qui permet d'extraire à partir d'une série de mesures la tendance sur la période étudiée et la composante journalière.Cette méthode, montre que le cycle nycthéméral de l'oxygène dissous garde son aspect et classique toute l'année, excepté sous la glace. Toutefois, l'amplitude journalière de la teneur en oxygène varie beaucoup selon la saison, et nous avons pu distinguer une période estivale où le métabolisme de l'étang semblait accéléré. L'analyse du cycle nycthéméral de l'oxygène dissous, dans lequel on distingue production et consommation, comparé à ceux de la température de l'eau et de l'insolation journalière moyenne, a permis d'étudier ce phénomène et de montrer l'importance des facteurs météorologiques dans la détermination du bilan de l'oxygène dissous en étang.Dissolved oxygen is a very important factor in fish ponds, particularly under intensive conditions. Thus, the daily fluctuations of dissolved oxygen have been studied in different countries and under different conditions (lakes, ponds, rivers), but with data series generally limited to a few measurements per day. The automatic data recorder of the IRRA'S experimental station provides very long series of data concerning of dissolved oxygen, temperature and meteorological factors through hourly measurements which allow the use of mathematical analysis like the moving average method. This automatic data recorder bas been in use since September 1987 and the data obtained have been analysed in research on summer oxygen deficit prevention. After 3 years' measurements it was interesting to investigate the annual change in the daily fluctuations of the dissolved oxygen. For this, daily hourly measurements of dissolved oxygen, temperature and solar radiations were taken and examined during 22 weeks from January 1988 to December 1989 (one week under ice cover). Oxygen data were analysed using seasonal decomposition by the moving average method, and the results were compared with the temperature and solar radiation measurements.The measurements were taken from 6 of the 16 IRRA'S experimental ponds (in the Dombes region, to the North-East of Lyon, France) and in a fish pond. All these ponds were semi-intensive fish-ponds stocked with Carp (Cyprinus carpio) Tench, (Tinca tinca), Grass Carp (Ctenopharingodon idella) and Silver Carp (Hypophthalmichthys molitrix).The seasonal decomposition through the moving average method devides the time series data into a trend (long term fluctuations), seasonal indices (or daily component) and residuals, but only seasonal indices, representing the daily variations, are studied here. The daily component was next spin into oxygen production and consumption if respiration is taken to be constant over one day and can be evaluated through the night oxygen decrease (EDELINE et al., 1968; ROMAIRE and BOYD, 1978; BARTHELEMY and COUTURE, 1990).Through this method, it appeared that the daily fluctuations of dissolved oxygen had the same classical aspect all the year round, except under ice cover, where it was impossible to observe a significant oxygen production. Such fluctuations, which are the result of the effect of oxygen production and consumption, have also been observed under different conditions (BOUD and LICHTKOPPLER, 1979; SIN and CHIU,1982; KEPENYES and VARADI, 1984; MARZOLF and SAUNDERS, 1984; GINOT, 1988; COUTURE, 1988). The aspect of the daily cycles was relatively constant but it was possible to distinguish 3 periods according to the amplitude of these cycles :- a winter period with less than 2 mg/l daily variations,- a summer period when these variations were greater titan 4 or 7 mg/l,- an intermediate period in spring and autumn.As these 3 periods did not occur at the same time of the year for 1988 & 1989, it appeared that the meteorological conditions (temperature and solar radiations) were important factors for determining these periods in the year.The study of oxygen production and consumption gave the same conclusions.These results have been compared with meteorological data : mean water temperature over 7-day periods (168 measurements), plus mean cumulative daily solar radiations over 7 days.There appeared significant correlations between the oxygen production and the consumption, with these meteorological factors, but these relations were different for the « summer » period (June to October) and the rest of the year. There was a delay between the period when temperature and solar radiations are best for primary production (June and July) and the period when the pond’s metabolism is maximum.There have been no measurements on primary production or algal population dynamics to explain these results clearly, but considering the observations of GRYGIEREK and WASILEWSKA (1979) and ELORANTA (1985) it is possible to give an explanation. In May-June the ponds are characterized by clear water (a higher than 60 cm transparency was observed) with low density algal populations, thus the pond ecosystem is not ready to use thermic and light energy. This delay between meteorological conditions and oxygen dynamics have been observed by ELORANTA (1985) and BOYD (1985).These results are useful in pond management, particularly when it is necessary to prevent oxygen depletion. The risk of oxygen deficits is greater in August-September, when the ecological conditions are very unstable owing to the important daily oxygen fluctuations. In this case, meteorological changes like temperature decreases or rain-fall can perturb the ecosystem and cause algal die-off with a great risk of oxygen depletion.The aim of this study was to show the possibilities of seasonal decomposition by the moving average method in the analysis of oxygen measurements. When it is possible to get long serie data, with constant skip, this method is very valuable for studying long term and daily fluctuations. The decomposition of the daily component through the method of EDELINE et al. (1968) also gives indications on primary production and oxygen consumption

A Compilation Flow for Parametric Dataflow: Programming Model, Scheduling, and Application to Heterogeneous MPSoC

International audienceEfficient programming of signal processing applications on embedded systems is a complex problem. High level models such as Synchronous dataflow (SDF) have been privileged candidates for dealing with this complexity. These models permit to express inherent application parallelism, as well as analysis for both verification and optimization. Parametric dataflow models aim at providing sufficient dynamicity to model new applications, while at the same time maintaining the high level of analyzability needed for efficient real life implementations. This paper presents a new compilation flow that targets parametric dataflows. Built on the LLVM compiler infrastructure, it offers an actor based C++ programming model to describe parametric graphs, a compilation front-end providing graph analysis features, and a retargetable back-end to map the application on real hardware. This paper gives an overview of this flow, with a specific focus on scheduling. The crucial gap between dataflow models and real hardware on which actor firing is not atomic, as well as the consequences on FIFOs sizing and execution pipelining are taken into account.The experimental results illustrate our compilation flow applied to compilation of 3GPP LTE-Advanced demodulation on a heterogeneous MPSoC with distributed scheduling features. This achieves performances similar to time-consuming hand made optimizations

Health Care Support Issues for Internationally Adopted Children: A Qualitative Approach to the Needs and Expectations of Families

International audienceBACKGROUND: Families of internationally adopted children may face specific problems with which general practitioners (GPs) may not be familiar. The aim of the study was to explore problems faced by families before, during and after the arrival of their internationally adopted child and to assess the usefulness of a specific medical structure for internationally adopted children, which could be a resource for the GP. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a qualitative study using individual semistructured guided conversations and interviewed 21 families that had adopted a total of 26 children internationally in the Puy de Dome department, France, in 2003. Quantitative data were used to describe the pathologies diagnosed and the investigations performed.Our study showed that the history of these families, from the start of the adoption project to its achievement, is complex and warrants careful analysis. Health-care providers should not only consider the medical aspects of adoption, but should also be interested in the histories of these families, which may play a role in the forming of attachments between the adoptee and their adoptive parents and prevent further trouble during the development of the child. We also showed that adoptive parents have similar fears or transient difficulties that may be resolved quickly by listening and reassurance. Most such families would support the existence of a specific medical structure for internationally adopted children, which could be a resource for the general practitioner. However, the health-care providers interviewed were divided on the subject and expressed their fear that a special consultation could be stigmatizing to children and families. CONCLUSIONS/SIGNIFICANCE: A specific consultation with well-trained and experienced practitioners acting in close collaboration with GPs and paediatricians may be of help in better understanding and supporting adopted children and their families

To respond or not to respond - a personal perspective of intestinal tolerance

For many years, the intestine was one of the poor relations of the immunology world, being a realm inhabited mostly by specialists and those interested in unusual phenomena. However, this has changed dramatically in recent years with the realization of how important the microbiota is in shaping immune function throughout the body, and almost every major immunology institution now includes the intestine as an area of interest. One of the most important aspects of the intestinal immune system is how it discriminates carefully between harmless and harmful antigens, in particular, its ability to generate active tolerance to materials such as commensal bacteria and food proteins. This phenomenon has been recognized for more than 100 years, and it is essential for preventing inflammatory disease in the intestine, but its basis remains enigmatic. Here, I discuss the progress that has been made in understanding oral tolerance during my 40 years in the field and highlight the topics that will be the focus of future research

Fracture–dislocation of the shoulder and brachial plexus palsy: a terrible association

Primary post-traumatic anterior dislocation of the shoulder with associated fracture of the greater tuberosity and brachial plexus injury is rare and, to our knowledge, has never previously been reported in the literature. We present a case of this unhappy triad in which a brachial plexus injury was diagnosed and treated 3 weeks later. The characteristics of this rare condition are discussed on the basis of our case and the published literature in order to improve early diagnosis and treatment of this lesion

CD25-Treg-depleting antibodies preserving IL-2 signaling on effector T cells enhance effector activation and antitumor immunity.

Intratumoral regulatory T cell (Treg) abundance associates with diminished anti-tumor immunity and poor prognosis in human cancers. Recent work demonstrates that CD25, the high affinity receptor subunit for IL-2, is a selective target for Treg depletion in mouse and human malignancies; however, anti-human CD25 antibodies have failed to deliver clinical responses against solid tumors due to bystander IL-2 receptor signaling blockade on effector T cells, which limits their anti-tumor activity. Here we demonstrate potent single-agent activity of anti-CD25 antibodies optimized to deplete Tregs whilst preserving IL-2-STAT5 signaling on effector T cells, and demonstrate synergy with immune checkpoint blockade in vivo. Pre-clinical evaluation of an anti-human CD25 (RG6292) antibody with equivalent features demonstrates, in both non-human primates and humanized mouse models, efficient Treg depletion with no overt immune-related toxicities. Our data supports the clinical development of RG6292 and evaluation of novel combination therapies incorporating non-IL-2 blocking anti-CD25 antibodies in clinical studies

Abscess Formation Following Spilled Gallstones During Laparoscopic Cholecystectomy

A review of the English literature concerning spilled gallstones during laparoscopic cholecystectomy is compared with one institution's experience of four cases during 1,726 laparoscopic cholecystectomies performed over a four-year period. Strategies regarding management and treatment are discussed

Oral Probiotic Control Skin Inflammation by Acting on Both Effector and Regulatory T Cells

Probiotics are believed to alleviate allergic and inflammatory skin disorders, but their impact on pathogenic effector T cells remains poorly documented. Here we show that oral treatment with the probiotic bacteria L. casei (DN-114 001) alone alleviates antigen-specific skin inflammation mediated by either protein-specific CD4+ T cells or hapten-specific CD8+ T cells. In the model of CD8+ T cell-mediated skin inflammation, which reproduces allergic contact dermatitis in human, inhibition of skin inflammation by L. casei is not due to impaired priming of hapten-specific IFNγ-producing cytolytic CD8+ effector T cells. Alternatively, L. casei treatment reduces the recruitment of CD8+ effector T cells into the skin during the elicitation (i.e. symptomatic) phase of CHS. Inhibition of skin inflammation by L. casei requires MHC class II-restricted CD4+ T cells but not CD1d-restricted NK-T cells. L casei treatment enhanced the frequency of FoxP3+ Treg in the skin and increased the production of IL-10 by CD4+CD25+ regulatory T cells in skin draining lymph nodes of hapten-sensitized mice. These data demonstrate that orally administered L. casei (DN-114 001) efficiently alleviate T cell-mediated skin inflammation without causing immune suppression, via mechanisms that include control of CD8+ effector T cells and involve regulatory CD4+ T cells. L. casei (DN-114 001) may thus represent a probiotic of potential interest for immunomodulation of T cell-mediated allergic skin diseases in human

CCL25/CCR9 Interactions Regulate Large Intestinal Inflammation in a Murine Model of Acute Colitis

CCL25/CCR9 is a non-promiscuous chemokine/receptor pair and a key regulator of leukocyte migration to the small intestine. We investigated here whether CCL25/CCR9 interactions also play a role in the regulation of inflammatory responses in the large intestine.Acute inflammation and recovery in wild-type (WT) and CCR9(-/-) mice was studied in a model of dextran sulfate sodium (DSS)-induced colitis. Distribution studies and phenotypic characterization of dendritic cell subsets and macrophage were performed by flow cytometry. Inflammatory bowel disease (IBD) scores were assessed and expression of inflammatory cytokines was studied at the mRNA and the protein level.CCL25 and CCR9 are both expressed in the large intestine and are upregulated during DSS colitis. CCR9(-/-) mice are more susceptible to DSS colitis than WT littermate controls as shown by higher mortality, increased IBD score and delayed recovery. During recovery, the CCR9(-/-) colonic mucosa is characterized by the accumulation of activated macrophages and elevated levels of Th1/Th17 inflammatory cytokines. Activated plasmacytoid dendritic cells (DCs) accumulate in mesenteric lymph nodes (MLNs) of CCR9(-/-) animals, altering the local ratio of DC subsets. Upon re-stimulation, T cells isolated from these MLNs secrete significantly higher levels of TNFα, IFNγ, IL2, IL-6 and IL-17A while down modulating IL-10 production.Our results demonstrate that CCL25/CCR9 interactions regulate inflammatory immune responses in the large intestinal mucosa by balancing different subsets of dendritic cells. These findings have important implications for the use of CCR9-inhibitors in therapy of human IBD as they indicate a potential risk for patients with large intestinal inflammation

Systemic IL-12 Administration Alters Hepatic Dendritic Cell Stimulation Capabilities

The liver is an immunologically unique organ containing tolerogenic dendritic cells (DC) that maintain an immunosuppressive microenvironment. Although systemic IL-12 administration can improve responses to tumors, the effects of IL-12-based treatments on DC, in particular hepatic DC, remain incompletely understood. In this study, we demonstrate systemic IL-12 administration induces a 2–3 fold increase in conventional, but not plasmacytoid, DC subsets in the liver. Following IL-12 administration, hepatic DC became more phenotypically and functionally mature, resembling the function of splenic DC, but differed as compared to their splenic counterparts in the production of IL-12 following co-stimulation with toll-like receptor (TLR) agonists. Hepatic DCs from IL-12 treated mice acquired enhanced T cell proliferative capabilities similar to levels observed using splenic DCs. Furthermore, IL-12 administration preferentially increased hepatic T cell activation and IFNγ expression in the RENCA mouse model of renal cell carcinoma. Collectively, the data shows systemic IL-12 administration enables hepatic DCs to overcome at least some aspects of the inherently suppressive milieu of the hepatic environment that could have important implications for the design of IL-12-based immunotherapeutic strategies targeting hepatic malignancies and infections