African humid periods triggered the reactivation of a large river system in Western Sahara

The Sahara experienced several humid episodes during the late Quaternary, associated with the development of vast fluvial networks and enhanced freshwater delivery to the surrounding ocean margins. In particular, marine sediment records off Western Sahara indicate deposition of river-borne material at those times, implying sustained fluvial discharges along the West African margin. Today, however, no major river exists in this area; therefore, the origin of these sediments remains unclear. Here, using orbital radar satellite imagery, we present geomorphological data that reveal the existence of a large buried paleodrainage network on the Mauritanian coast. On the basis of evidence from the literature, we propose that reactivation of this major paleoriver during past humid periods contributed to the delivery of sediments to the Tropical Atlantic margin. This finding provides new insights for the interpretation of terrigenous sediment records off Western Africa, with important implications for our understanding of the paleohydrological history of the Sahara.

Given the absence of a major river system in the Western Sahara, the source of late Quaternary fluvial sediments along the West African margin remains unclear. Here, the authors present geomorphological data that reveal the existence of a large buried paleodrainage network on the Mauritanian coast.

Alternative growth functions for predicting body, carcass, and breast weight in ducks: Lomolino equation and extreme value function

In this study, 2 alternative growth functions, the Lomolino and the extreme value function (EVF), are introduced and their ability to predict body, carcass, and breast weight in ducks evaluated. A comparative study was carried out of these equations with standard growth functions: Gompertz, exponential, Richards, and generalized Michaelis-Menten. Goodness of fit of the functions was evaluated using R(2), mean square error, Akaike information criterion, and Bayesian information criterion, whereas bias factor, accuracy factor, Durbin-Watson statistic, and number of runs of sign were the criteria used for analysis of residuals. Results showed that predictive performance of all functions was acceptable, though the Richards and exponential equations failed to converge in a few cases for both male and female ducks. Based on goodness-of-fit statistics, the Richards, Gompertz, and EVF were the best equations whereas the worst fits to the data were obtained with the exponential. Analysis of residuals indicated that, for the different traits investigated, the least biased and the most accurate equations were the Gompertz, EVF, Richards, and generalized Michaelis-Menten, whereas the exponential was the most biased and least accurate. Based on the Durbin-Watson statistic, all models generally behaved well and only the exponential showed evidence of autocorrelation for all 3 traits investigated. Results showed that with all functions, estimated final weights of males were higher than females for the body, carcass, and breast weight profiles. The alternative functions introduced here have desirable advantages including flexibility and a low number of parameters. However, because this is probably the first study to apply these functions to predict growth patterns in poultry or other animals, further analysis of these new models is suggested.

[Radiotherapy and implantable medical device: example of infusion pumps]

Indication for radiotherapy is often questioned for patients equipped with implantable medical devices like infusion pumps as the radiation tolerance is poor or not known. We report here on the case of a patient who we treated with pelvic radiotherapy for cervical cancer and who had an infusion pump in iliac fossa. We conducted a series of tests on five identical pumps that insured that the treatment protocol is harmless to the implanted device.

Interpreting experimental data on egg production--applications of dynamic differential equations

This contribution focuses on applying mathematical models based on systems of ordinary first-order differential equations to synthesize and interpret data from egg production experiments. Models based on linear systems of differential equations are contrasted with those based on nonlinear systems. Regression equations arising from analytical solutions to linear compartmental schemes are considered as candidate functions for describing egg production curves, together with aspects of parameter estimation. Extant candidate functions are reviewed, a role for growth functions such as the Gompertz equation suggested, and a function based on a simple new model outlined. Structurally, the new model comprises a single pool with an inflow and an outflow. Compartmental simulation models based on nonlinear systems of differential equations, and thus requiring numerical solution, are next discussed, and aspects of parameter estimation considered. This type of model is illustrated in relation to development and evaluation of a dynamic model of calcium and phosphorus flows in layers. The model consists of 8 state variables representing calcium and phosphorus pools in the crop, stomachs, plasma, and bone. The flow equations are described by Michaelis-Menten or mass action forms. Experiments that measure Ca and P uptake in layers fed different calcium concentrations during shell-forming days are used to evaluate the model. In addition to providing a useful management tool, such a simulation model also provides a means to evaluate feeding strategies aimed at reducing excretion of potential pollutants in poultry manure to the environment.

Identification of Races 0 and 2 of Cladosporium fulvum (syn Passalora fulva) on Tomato in the Cinturón Hortícola de La Plata, Argentina

Surveys aimed at evaluating the incidence and severity of a new disease that developed in greenhouses cultivated with tomato (Solanum lycopersicum L.) were performed during 2009 and 2010 in greenhouses of the cultivars Elpida (Enza Zaden) and Colibrí (Clause) in an area of tomato production known as the Cinturón Hortícola de La Plata (the "horticultural belt of La Plata"). The disease had a 100% prevalence and 90% incidence within the ten 250 m² greenhouses that were monitored in 2009, 2010, and 2011. In two consecutive assays, severity was 40%. The wide distribution of the disease suggests that the tomato hybrids under use lack resistance genes. The upper surface of diseased leaves had pale green to yellowish, 1- to 1.5-cm spots with undefined margins that progressed to a yellowish brown color, while on the lower side they had pale brown to brown sporulation of fungal conidiophores and conidia. Monosporic fungal cultures were obtained by needle transfer of conidia from sporulating areas of leaves (n = 20) to water agar medium. On 2% potato dextrose agar (PDA) the colonies of the relatively low growing fungus were strongly pigmented, greenish grey, and black on the reverse of the plate. The fungus developed one-celled, pale olive-green, ovoid conidia on long, branched chains, which arose from pigmented conidiophores, corresponding to the description of Cladosporium fulvum made by Joosten and de Wit (1). The identity of two isolates was confirmed by amplifying the 580-bp ITS sequences by means of primers ITS4 (5'-TCCTCCGCTTATTGATATGC-3') and ITS5 (5'-GAATTCGGAAGTAAAAGTCGTAACAAGG-3') (ITS sequence Race 0 JQ768324.1 and Race 2 JQ768325.1). Both were 100% homologous to the ITS sequences of C. fulvum strains ATCC44962 (AF393700) and ATCC44960 (AF303701). Monosporic cultures of four isolates, each obtained from leaves collected from different plants growing in different greenhouses, were inoculated on a set of differential genotypes of tomato: cvs. Moneymaker, Cf-0, Cf-2, Cf-4, Cf-5, and Cf-9 (kindly provided by the Laboratory of Phytopathology of Wageningen University). Three plants of each tomato genotype at the 5 to 6 true leaf stage were inoculated by spraying a 10⁵ conidia/ml conidial suspension of C. fulvum on the leaflets of the 3rd and 4th leaf. Inoculation tests of each isolate were repeated at least twice. After inoculation, plants were grown in the greenhouse at 13 to 29°C and 99% relative humidity. However, for the first 20 h after inoculation, plants were kept in the dark. They were regularly monitored and were scored as resistant or susceptible at 20 days after inoculation. Susceptible genotypes developed pale green to yellow spots on the abaxial leaf surface and pale brown to olivaceous brown sporulation on the adaxial side. Plants lacking disease symptoms were considered resistant. Inoculated fungi were reisolated from infected tissue and the identity of the fungal cultures confirmed based on morphology and the ITS sequence. Based on the reactions of the tomato genotypes, two races were identified, three isolates (race 2) developed symptoms only in cv. MM Cf-2, while the remaining isolate (race 0) provoked symptoms only in cv. MM Cf-0. Reference: (1) M. Joosten and P. de Wit. Annu Rev Phytopathol. 37:335, 1999.

KIT-D816V oncogenic activity is controlled by the juxtamembrane docking site Y568-Y570

Mutation of KIT receptor tyrosine kinase at residue D816 results in ligand-independent constitutive kinase activity. This mutation occurs in most patients with mastocytosis, a myeloproliferative neoplasm, and is detected at lower frequencies in acute myeloid leukemia and in germ cell tumors. Other KIT mutations occur in gastrointestinal stromal tumors (GIST) and mucosal melanoma. KIT is considered as a bona fide therapeutic target as c-kit mutations are driving oncogenes in these pathologies. However, several evidences suggest that KIT-D816V mutant is not as aggressive as other KIT mutants. Here, we show that an intracellular docking site in the juxtamembrane region of KIT maintains a negative regulation on KIT-D816V transforming potential. Sixteen signaling proteins were shown to interact with this motif. We further demonstrate that mutation of this site results in signaling modifications, altered gene expression profile and increased transforming activity of KIT-D816V mutant. This result was unexpected as mutations of the homologous sites on wild-type (WT) KIT, or on the related oncogenic FLT3-ITD receptor, impair their function. Our results support the hypothesis that, KIT-D816V mutation is a mild oncogenic event that is sufficient to confer partial transforming properties, but requires additional mutations to acquire its full transforming potential.

Abstract P3-03-01: 3D mapping of total choline in human breast cancer using high-speed MR spectroscopic imaging at 3T: initial experience during neoadjuvant therapy

OBJECTIVE: To assess the feasibility of quantitative high-speed MR spectroscopic imaging (MRSI) of total Choline (tCho) as an adjunct to dynamic-contrast enhanced MRI to improve lesion characterization and monitor treatment response in patients undergoing neoadjuvant chemotherapy (NAC).

METHODS: Twelve patients with infiltrating ductal carcinoma (Table 1) were studied using a clinical 3T MR scanner (Siemens, Erlangen, Germany) equipped with 8- and 16-channel breast array (Hologic Inc., Bedford, MA). Four patients were studied before NAC. Four patients were studied once during NAC. Two patients were studied before and within 2–7 days of treatment initiation. One of these patients participated in an additional scan after 5 months of treatment. Two additional patients were studied at 3 time points during NAC. Measurements were performed using PRESS prelocalized 3D Proton-Echo-Planar-Spectroscopic-Imaging (PEPSI) using TR/TE=2000ms/135ms, matrix size up to 32×16×8, voxel size = 1cc, and total acquisition time of 10 minutes (including water reference scan). Additional data were collected at TE 60 ms to enhance sensitivity for detecting tCho and J-coupled resonances. TE-averaging (8 steps, DTE: 2.5 ms) was employed to minimize gradient sideband artifacts. Quantification of tCho in reference to tissue water was performed using spectral fitting and relaxation correction.

RESULTS: Strongly elevated tCho with maximum concentration up to 5.3 mmol/kg was measured in 9 patients with enhancing lesions larger than 2 cc volume (Table 2). Decreases in tCho were measured in all four patients who were followed during neoadjuvant chemotherapy. Decreases in tCho were measurable during the first week of neoadjuvant treatment in responders, consistent with previous studies. Our preliminary data also indicate that the combination of concentration and spatial extent of detectable tCho may be the most sensitive marker of treatment response.

[Infants and toddlers behavioral and functional disorders: characteristics, mother-child interactions, alliance and outcome after a brief parents-child psychotherapy. A pilot study]

OBJECTIVES

Functional and behavioral disorders are the most frequent reasons for consultation in infant psychiatry, but there are still few studies about the efficacy of parents-child psychotherapies. Functional disorders appear to be easier to treat than behavioral disorders. The aim of this study was: (1) to assess outcome after a brief psychotherapy in a population of 49 infants aged 3 to 30 months, presenting functional or behavioral disorders; (2) to compare characteristics before therapy and outcomes for children with functional disorders and with behavioral disorders, to have a better understanding of the worse outcome of children with behavioral disorders.

METHODS

Two assessments were performed, one before treatment and the second a month after the end of the therapy including the infant's symptoms (Symptom Check-list), parents' anxious and depressive symptoms (Hospital Anxiety and Depression scale) and mother-infant interactions (Crittenden Experimental Index of adult-infant relationship). The therapeutic alliance was assessed by the therapist and the parents after the first consultation (Working Alliance Inventory).

RESULTS

The assessments after therapy show complete or partial improvement in the child's symptoms, in the mother's anxious and depressive symptoms and in the father's anxious symptoms. During interaction, the mothers become more sensible, the number of controlling and of unresponsive mothers decrease, while the children become more cooperative and less passive. Initial characteristics and outcome are however different according to the type of the child's disorder. The children with behavioral disorders are older and present an association of several symptoms. The disorder onset is later. Their mothers are, before therapy, more anxious and depressive. The therapeutic alliance is weaker. After therapy, despite the fact that their mothers' affective state and that interactive behavior improves, the mothers are more anxious and less sensible, while the children no longer differ from the group without behavioral disorder from the point of view of opposition (assessed during mother-child interaction).

CONCLUSION

Although this study is limited by the lack of a control group and the sample size, it underlines some particularities of infants and toddlers presenting behavioral disorders and the difficulties involved in their treatment. One can wonder if these characteristics are specific of the behavioral disorders or if they are the result of an older dysfunction, complicated by the developmental evolution of the child and the duration of the difficulties. The small number of cases, among the children with behavioral disorders, presenting a preexistent functional disorder, the absence of difference in the duration of the disorders, and the different disorder's onset plead in favor of the first hypothesis. The behavioral disorders often associate child psychopathology, dysfunctional parents-child-relationships and environmental factors difficult to modify with a brief therapy focused on the relationship. It would appear necessary to develop specific treatments for this population.