Diagnóstico sobre el estado de conocimiento y conservación de la Flora Acuatica y Mamiferos asociados a los Humedalesde las Cuencas, Orinoco, Magdalena y Cauca

Colombia es un País con importantes recursos Hídricos a nivel continental, representados por una gran cantidad de cuerpos de agua tanto de tipo lotico como lentico que soportan importantes servicios eco sistémico y social. Se estima que el área total de los Humedales del país es de 20´252.500 hectáreas, representados por lagos, pantanos y turberas, ciénagas, llanuras y Bosques inundados (Ministerio del Medio Ambiente, 1999), las Ciénagas y otros cuerpos de agua con mayor profundidad abarcan aproximadamente 5´622.750 ha, las cuales se encuentran principalmente en los departamentos de Bolívar y Magdalena. Las lagunas representan cerca de 22.950 ha y las sabanas inundables cubren una superficie total aproximada 9´255.475 ha, ubicadas en los departamentos del Amazonas, Guainía y Guaviare. Los bosques inundables, por su parte, en conjunto representan cerca de 5´351.325 ha, encontrándose en su mayoría en la Orinoquía, Amazonia, Bajo Magdalena y en menos medida en la zona Pacífica (Ministerio del Medio Ambiente, 1999).BogotáBiología de la Conservació

Intrinsic plasticity of silicon nanowire neurotransistors for dynamic memory and learning functions

Neuromorphic architectures merge learning and memory functions within a single unit cell and in a neuron-like fashion. Research in the field has been mainly focused on the plasticity of artificial synapses. However, the intrinsic plasticity of the neuronal membrane is also important in the implementation of neuromorphic information processing. Here we report a neurotransistor made from a silicon nanowire transistor coated by an ion-doped sol-gel silicate film that can emulate the intrinsic plasticity of the neuronal membrane. The neurotransistors are manufactured using a conventional complementary metal-oxide-semiconductor process on an 8-inch (200 mm) silicon-on-insulator wafer. Mobile ions allow the film to act as a pseudo-gate that generates memory and allows the neurotransistor to display plasticity. We show that multiple pulsed input signals of the neurotransistor are non-linearly processed by sigmoidal transformation into the output current, which resembles the functioning of a neuronal membrane. The output response is governed by the input signal history, which is stored as ionic states within the silicate film, and thereby provides the neurotransistor with learning capabilities. A neurotransistor made from a silicon nanowire transistor coated by an ion-doped sol-gel silicate film can emulate the intrinsic plasticity of the neuronal membrane.11Nsciescopu

Pitx2 regulates gonad morphogenesis

Organ shape and size, and, ultimately, organ function, relate in part to the cell and tissue spatial arrangement that takes place during embryonic development. Despite great advances in the genetic regulatory networks responsible for tissue and organ development, it is not yet clearly understood how specific gene functions are linked to the specific morphogenetic processes underlying the internal organ asymmetries found in vertebrate animals. During female chick embryogenesis, and in contrast to males where both testes develop symmetrically, asymmetrical gonad morphogenesis results in only one functional ovary. The disposition of paired organs along the left–right body axis has been shown to be regulated by the activity of the homeobox containing gene pitx2. We have found that pitx2 regulates cell adhesion, affinity, and cell recognition events in the developing gonad primordium epithelia. This in turn not only allows for proper somatic development of the gonad cortex but also permits the proliferation and differentiation of primordial germ cells. We illustrate how Pitx2 activity directs asymmetrical gonad morphogenesis by controlling mitotic spindle orientation of the developing gonad cortex and how, by modulating cyclinD1 expression during asymmetric ovarian development, Pitx2 appears to control gonad organ size. All together our observations indicate that the effects elicited by Pitx2 during the development of the female chick ovary are critical for cell topology, growth, fate, and ultimately organ morphogenesis and function

Overall survival in the OlympiA phase III trial of adjuvant olaparib in patients with germline pathogenic variants in BRCA1/2 and high-risk, early breast cancer

International audienc

Overall survival in the OlympiA phase III trial of adjuvant olaparib in patients with germline pathogenic variants in BRCA1/2 and high-risk, early breast cancer

Background: The randomized, double-blind OlympiA trial compared 1 year of the oral poly(adenosine diphosphate-ribose) polymerase inhibitor, olaparib, to matching placebo as adjuvant therapy for patients with pathogenic or likely pathogenic variants in germline BRCA1 or BRCA2 (gBRCA1/2pv) and high-risk, human epidermal growth factor receptor 2-negative, early breast cancer (EBC). The first pre-specified interim analysis (IA) previously demonstrated statistically significant improvement in invasive disease-free survival (IDFS) and distant disease-free survival (DDFS). The olaparib group had fewer deaths than the placebo group, but the difference did not reach statistical significance for overall survival (OS). We now report the pre-specified second IA of OS with updates of IDFS, DDFS, and safety. Patients and methods: One thousand eight hundred and thirty-six patients were randomly assigned to olaparib or placebo following (neo)adjuvant chemotherapy, surgery, and radiation therapy if indicated. Endocrine therapy was given concurrently with study medication for hormone receptor-positive cancers. Statistical significance for OS at this IA required P < 0.015. Results: With a median follow-up of 3.5 years, the second IA of OS demonstrated significant improvement in the olaparib group relative to the placebo group [hazard ratio 0.68; 98.5% confidence interval (CI) 0.47-0.97; P = 0.009]. Four-year OS was 89.8% in the olaparib group and 86.4% in the placebo group (Δ 3.4%, 95% CI -0.1% to 6.8%). Four-year IDFS for the olaparib group versus placebo group was 82.7% versus 75.4% (Δ 7.3%, 95% CI 3.0% to 11.5%) and 4-year DDFS was 86.5% versus 79.1% (Δ 7.4%, 95% CI 3.6% to 11.3%), respectively. Subset analyses for OS, IDFS, and DDFS demonstrated benefit across major subgroups. No new safety signals were identified including no new cases of acute myeloid leukemia or myelodysplastic syndrome. Conclusion: With 3.5 years of median follow-up, OlympiA demonstrates statistically significant improvement in OS with adjuvant olaparib compared with placebo for gBRCA1/2pv-associated EBC and maintained improvements in the previously reported, statistically significant endpoints of IDFS and DDFS with no new safety signals