On circuit functionality in boolean networks.

It has been proved, for several classes of continuous and discrete dynamical systems, that the presence of a positive (resp. negative) circuit in the interaction graph of a system is a necessary condition for the presence of multiple stable states (resp. a cyclic attractor). A positive (resp. negative) circuit is said to be functional when it "generates" several stable states (resp. a cyclic attractor). However, there are no definite mathematical frameworks translating the underlying meaning of "generates." Focusing on Boolean networks, we recall and propose some definitions concerning the notion of functionality along with associated mathematical results.

"As you receive with one hand, so should you give with the other": the mutual-help practices of Cape Verdeans on the Lisbon periphery”

Rural Cape Verdeans employ a number of mutual-help practices to mitigate the uncertainties surrounding activities fundamental to their subsistence. One of these practices is djunta mon (‘to work together’), a loosely planned, non-monetized system of allocating labor at peak intervals during the growing season. By means of djunta mon, neighbors or family members work in each other’s fields until the tasks of every landowning participant are complete. Alongside djunta mon in rural Cape Verde exist a number of other non-remunerated mutual-help practices, such as djuda mutua (‘mutual help’) and laja kaza (‘to add concrete to one’s house’). While less visible than djunta mon, they are nonetheless important in completing tasks essential to rural life in the islands. In this thesis, I will attempt to show how Cape Verdean immigrants in Lisbon have adapted the mutual-help practices of rural Cape Verde to a new, transnational context. The iterations of these practices in Lisbon differ from their rural counterparts in that they involve fewer people, occur on a year-round basis, and are concerned primarily with domestic work. They also help people find employment, access childcare, secure interest-free credit, and construct or repair houses. I will argue that extensive mutual-help ties ensure Cape Verdean migrants in Lisbon a sufficient pool of family and friends upon which they can rely for support and assistance. An additional element I will explore is the perception among Cape Verdean immigrants that these mutual-help practices seem to be occurring with less frequency. While this shift is in part due to the availability of other means of support, I will contend that the changing attitude of Cape Verdeans towards mutual help is also due to their encountering neoliberal notions of ‘self-accountability.’ Thus, Cape Verdeans perceive that their mutual-help practices are in decline, while simultaneously needing the material support that they provide.

Software per al cronometratge de temps mitjançant sensors digitals

L’Slot, conegut per tots amb el nom d’Scalextric, s’ha implantat com a una forma d’oci habitual, la pràctica del qual no queda restringida als més petits, sinó que cada vegada crea més afició entre els grans. El fet que l’Slot s’hagi extès entre els adults n’ha revolucionat la pràctica. L’entrada al mercat de l’Slot de gent adulta, i amb poder adquisitiu molt superior als adolescents, ha provocat que les marques especialitzades vagin evolucionant els seus productes cada vegada més. Totes les marques s’han vist obligades a desenvolupar vehicles més competitius i alhora treure al mercat accessoris que augmentin la realitat del joc. Una de les necessitats que s’ha creat és la de competir entre jugadors. Aquesta competició tan pot ser en forma de carrera entre diversos participants, com de forma individual, cronometrant el temps de cada participant en un circuit. L’objectiu principal del projecte és crear un sistema capaç de realitzar cronometratges en temps real mitjançant sensors digitals ja existents en el mercat de l’Slot i poder controlar i visualitzar la informació des d’un PC. Per a poder captar els senyals dels sensors s’ha utilitzat un sistema microcontrolat, que garanteix gran velocitat d’adquisició, processament de dades i transmissió. La comunicació del Microcontrolador amb el PC s’ha realizat mitjançant el bus USB. El PC serà el controlador del sistema i donarà les ordres al Microcontrolador, podent així tenir control total sobre el funcionament del programa. També serà el PC el que tractarà els crocometratges enregistrats i els mostrarà per pantalla

Is adjuvant chemotherapy of benefit for postmenopausal women who receive endocrine treatment for highly endocrine-responsive, node-positive breast cancer? International Breast Cancer Study Group Trials VII and 12-93.

To compare the efficacy of chemoendocrine treatment with that of endocrine treatment (ET) alone for postmenopausal women with highly endocrine responsive breast cancer. In the International Breast Cancer Study Group (IBCSG) Trials VII and 12-93, postmenopausal women with node-positive, estrogen receptor (ER)-positive or ER-negative, operable breast cancer were randomized to receive either chemotherapy or endocrine therapy or combined chemoendocrine treatment. Results were analyzed overall in the cohort of 893 patients with endocrine-responsive disease, and according to prospectively defined categories of ER, age and nodal status. STEPP analyses assessed chemotherapy effect. The median follow-up was 13 years. Adding chemotherapy reduced the relative risk of a disease-free survival event by 19% (P = 0.02) compared with ET alone. STEPP analyses showed little effect of chemotherapy for tumors with high levels of ER expression (P = 0.07), or for the cohort with one positive node (P = 0.03). Chemotherapy significantly improves disease-free survival for postmenopausal women with endocrine-responsive breast cancer, but the magnitude of the effect is substantially attenuated if ER levels are high.

Analog circuit for real-time computation of respiratory mechanical impedance in sleep studies

The aim of this work was to develop a low-cost circuit for real-time analog computation of the respiratory mechanical impedance in sleep studies. The practical performance of the circuit was tested in six patients with obstructive sleep apnea. The impedance signal provided by the analog circuit was compared with the impedance calculated simultaneously with a conventional computerized system. We concluded that the low-cost analog circuit developed could be a useful tool for facilitating the real-time assessment of airway obstruction in routine sleep studies.

A current-mode interface circuit for a piezoresistive pressure sensor

An interfacing circuit for piezoresistive pressure sensors based on CMOS current conveyors is presented. The main advantages of the proposed interfacing circuit include the use of a single piezoresistor, the capability of offset compensation, and a versatile current-mode configuration, with current output and current or voltage input. Experimental tests confirm linear relation of output voltage versus piezoresistance variation.

Analog circuit for real-time computation of respiratory mechanical impedance in sleep studies

The aim of this work was to develop a low-cost circuit for real-time analog computation of the respiratory mechanical impedance in sleep studies. The practical performance of the circuit was tested in six patients with obstructive sleep apnea. The impedance signal provided by the analog circuit was compared with the impedance calculated simultaneously with a conventional computerized system. We concluded that the low-cost analog circuit developed could be a useful tool for facilitating the real-time assessment of airway obstruction in routine sleep studies.

El circuit comercial de Barcino: reflexions al voltant de les marques amfòriques

Barcino és encara avui una ciutat romana poc coneguda de la província Tarraconense, que segons la majoria d¿especialistes fou fundada per raons polítiques. Malgrat això, una anàlisi detallada de les característiques econòmiques suggereixen que es va crear com a resultat de necessitats comercials, ja que es localitzava en una de les millors zones portuàries del NE de la península. L¿article present pretén reconstruir tot el circuit comercial de Barcino a partir de les nombroses estampilles d¿àmfores trobades en les excavacions. Aquestes marques comercials no solament evidencien una pròspera producció de vi en l¿àrea, sinó també la corresponent demanda externa

A circuit-based gatekeeper for adult neural stem cell proliferation: Parvalbumin-expressing interneurons of the dentate gyrus control the activation and proliferation of quiescent adult neural stem cells.

Newborn neurons are generated in the adult hippocampus from a pool of self-renewing stem cells located in the subgranular zone (SGZ) of the dentate gyrus. Their activation, proliferation, and maturation depend on a host of environmental and cellular factors but, until recently, the contribution of local neuronal circuitry to this process was relatively unknown. In their recent publication, Song and colleagues have uncovered a novel circuit-based mechanism by which release of the neurotransmitter, γ-aminobutyric acid (GABA), from parvalbumin-expressing (PV) interneurons, can hold radial glia-like (RGL) stem cells of the adult SGZ in a quiescent state. This tonic GABAergic signal, dependent upon the activation of γ(2) subunit-containing GABA(A) receptors of RGL stem cells, can thus prevent their proliferation and subsequent maturation or return them to quiescence if previously activated. PV interneurons are thus capable of suppressing neurogenesis during periods of high network activity and facilitating neurogenesis when network activity is low.

A new concept of integrated cardiopulmonary bypass circuit.

OBJECTIVE: Standard cardiopulmonary bypass (CPB) circuits with their large surface area and volume contribute to postoperative systemic inflammatory reaction and hemodilution. In order to minimize these problems a new approach has been developed resulting in a single disposable, compact arterio-venous loop, which has integral kinetic-assist pumping, oxygenating, air removal, and gross filtration capabilities (CardioVention Inc., Santa Clara, CA, USA). The impact of this system on gas exchange capacity, blood elements and hemolysis is compared to that of a conventional circuit in a model of prolonged perfusion. METHODS: Twelve calves (mean body weight: 72.2+/-3.7 kg) were placed on cardiopulmonary bypass for 6 h with a flow of 5 l/min, and randomly assigned to the CardioVention system (n=6) or a standard CPB circuit (n=6). A standard battery of blood samples was taken before bypass and throughout bypass. Analysis of variance was used for comparison. RESULTS: The hematocrit remained stable throughout the experiment in the CardioVention group, whereas it dropped in the standard group in the early phase of perfusion. When normalized for prebypass values, both profiles differed significantly (P<0.01). Both O2 and CO2 transfers were significantly improved in the CardioVention group (P=0.04 and P<0.001, respectively). There was a slightly higher pressure drop in the CardioVention group but no single value exceeded 112 mmHg. No hemolysis could be detected in either group with all free plasma Hb values below 15 mg/l. Thrombocyte count, when corrected by hematocrit and normalized by prebypass values, exhibited an increased drop in the standard group (P=0.03). CONCLUSION: The CardioVention system with its concept of limited priming volume and exposed foreign surface area, improves gas exchange probably because of the absence of detectable hemodilution, and appears to limit the decrease in the thrombocyte count which may be ascribed to the reduced surface. Despite the volume and surface constraints, no hemolysis could be detected throughout the 6 h full-flow perfusion period.