Using active learning for monitoring networks design: The example of wind power plants sites evaluation

Locating new wind farms is of crucial importance for energy policies of the next decade. To select the new location, an accurate picture of the wind fields is necessary. However, characterizing wind fields is a difficult task, since the phenomenon is highly nonlinear and related to complex topographical features. In this paper, we propose both a nonparametric model to estimate wind speed at different time instants and a procedure to discover underrepresented topographic conditions, where new measuring stations could be added. Compared to space filling techniques, this last approach privileges optimization of the output space, thus locating new potential measuring sites through the uncertainty of the model itself.

Transplantation tolerance induced by regulatory T cells: in vivo mechanisms and sites of action.

The mechanisms by which CD4(+)CD25(+)Foxp3(+) T (Treg) cells regulate effector T cells in a transplantation setting and their in vivo homeostasis still remain to be clarified. Using a mouse adoptive transfer model, we analyzed the in vivo expansion, trafficking, and effector function of alloreactive T cells and donor-specific Treg cells, in response to a full-thickness skin allograft. Fluorescent-labeled CD4(+)CD25(-) and antigen-specific Treg cells were transferred alone or co-injected into syngeneic BALB/c-Nude recipients transplanted with skins from (C57BL/6 x BALB/c) F1 donors. Treg cells divided in vivo, migrated and accumulated in the allograft draining lymph nodes as well as within the graft. The co-transfer of Treg cells did not modify the early activation and homing of CD4(+)CD25(-) T cells in secondary lymphoid organs. However, in the presence of Treg cells, alloreactive CD4(+)CD25(-) T cells produced significantly less IFN-gamma and were present in reduced numbers in the secondary lymphoid organs. Furthermore, time-course studies showed that Treg cells were recruited into the allograft at a very early stage after transplantation and effectively prevented the infiltration of effector T cells. In conclusion, suppression of rejection requires the early recruitment to the site of antigenic challenge of donor-specific Treg cells, which then mainly regulate the effector arm of T cell alloresponses.

Sub-cortical and brainstem sites associated with chemo-stimulated increases in ventilation in humans.

We investigated the neural basis for spontaneous chemo-stimulated increases in ventilation in awake, healthy humans. Blood oxygen level dependent (BOLD) functional MRI was performed in nine healthy subjects using T2 weighted echo planar imaging. Brain volumes (52 transverse slices, cortex to high spinal cord) were acquired every 3.9 s. The 30 min paradigm consisted of six, 5-min cycles, each cycle comprising 45 s of hypoxic-isocapnia, 45 s of isooxic-hypercapnia and 45 s of hypoxic-hypercapnia, with 55 s of non-stimulatory hyperoxic-isocapnia (control) separating each stimulus period. Ventilation was significantly (p<0.001) increased during hypoxic-isocapnia, isooxic-hypercapnia and hypoxic-hypercapnia (17.0, 13.8, 24.9 L/min respectively) vs. control (8.4 L/min) and was associated with significant (p<0.05, corrected for multiple comparisons) signal increases within a bilateral network that included the basal ganglia, thalamus, red nucleus, cerebellum, parietal cortex, cingulate and superior mid pons. The neuroanatomical structures identified provide evidence for the spontaneous control of breathing to be mediated by higher brain centres, as well as respiratory nuclei in the brainstem.

Which anatomical sites should be sampled for screening of methicillin-resistant Staphylococcus aureus carriage by culture or by rapid PCR test?

The nose is the anatomical site usually recommended for methicillin-resistant Staphylococcus aureus (MRSA) screening. Other sites are also recommended, but are more controversial. We showed that the sensitivities of MRSA detection from nasal swabs alone were 48% and 62% by culture or by rapid PCR test, respectively. These percentages increased to 79% and 92% with the addition of groin swabs, and to 96% and 99% with the addition of groin and throat swabs. In conclusion, neither by culture nor by rapid PCR test is nose sampling alone sufficient for MRSA detection. Additional anatomical sites should include at least the groin and throat.

Ectodysplasin A (EDA) - EDA receptor signalling and its pharmacological modulation.

The TNF family ligand ectodysplasin A (EDA) regulates the induction, morphogenesis and/or maintenance of skin-derived structures such as teeth, hair, sweat glands and several other glands. Deficiencies in the EDA - EDA receptor (EDAR) signalling pathway cause hypohidrotic ectodermal dysplasia (HED). This syndrome is characterized by the absence or malformation of several skin-derived appendages resulting in hypotrychosis, hypodontia, heat-intolerance, dry skin and dry eyes, susceptibility to airways infections and crusting of various secretions. The EDA-EDAR system is an important effector of canonical Wnt signalling in developing skin appendages. It functions by stimulating NF-κB-mediated transcription of effectors or inhibitors of the Wnt, Sonic hedgehog (SHH), fibroblast growth factor (FGF) and transforming growth factor beta (TGFβ) pathways that regulate interactions within or between epithelial and mesenchymal cells and tissues. In animal models of Eda-deficiency, soluble EDAR agonists can precisely correct clinically relevant symptoms with low side effects even at high agonist doses, indicating that efficient negative feedback signals occur in treated tissues. Hijacking of the placental antibody transport system can help deliver active molecules to developing foetuses in a timely manner. EDAR agonists may serve to treat certain forms of ectodermal dysplasia.