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851.
Helena Borges Martins da Silva Paro Renata Rodrigues Catani Rafaela Cordeiro Freire Gabriela Rondon 《Developing world bioethics》2023,23(2):147-153
In Brazil, abortion is only allowed in cases of rape, serious risk to a woman's life or fetal anecephaly. Legal abortion services cover less than 4% of the Brazilian territory and only 1,800 procedures are performed, in average, per year. During the COVID-19 pandemic, almost half of the already few Brazilian abortion clinics shut down and women had to travel even longer distances, reaching abortion services at later gestational ages. In this paper, we describe three bottom-up advocacy strategies that emerged from difficulties deepened during the COVID-19 pandemic at a single abortion service in Brazil, amidst anti-gender policies from the federal government. Telemedicine abortion, outpatient surgical abortion and the provision of abortion after 20 weeks' gestation are important strategies that may reduce inequalities that impact the most vulnerable populations, such as black and indigenous women, children, adolescents and women experiencing domestic violence. 相似文献
852.
Daniela R. Rosa Iolanda C.S. Duarte N. Katia Saavedra Maria B. Varesche Marcelo Zaiat Magali C. Cammarota Denise M.G. Freire 《Bioresource technology》2009,100(24):6170-6176
The effect of a lipase-rich fungal enzymatic preparation, produced by a Penicillium sp. during solid-state fermentation, was evaluated in an anaerobic digester treating dairy wastewater with 1200 mg of oil and grease/L. The oil and grease hydrolysis step was carried out with 0.1% (w/v) of solid enzymatic preparation at 30 °C for 24 h, and resulted in a final free acid concentration eight times higher than the initial value. The digester operated in sequential batches of 48 h at 30 °C for 245 days, and had high chemical oxygen demand (COD) removal efficiencies (around 90%) when fed with pre-hydrolyzed wastewater. However, when the pre-hydrolysis step was removed, the anaerobic digester performed poorly (with an average COD removal of 32%), as the oil and grease accumulated in the biomass and effluent oil and grease concentration increased throughout the operational period. PCR-DGGE analysis of the Bacteria and Archaea domains revealed remarkable differences in the microbial profiles in trials conducted with and without the pre-hydrolysis step, indicating that differences observed in overall parameters were intrinsically related to the microbial diversity of the anaerobic sludge. 相似文献
853.
Theory of DNA melting curves 总被引:15,自引:0,他引:15
Exact algorithms for the calculation of melting curves of heterogeneous DNA with N base pairs apparently require computer time proportional to N2. However, it is shown that a decomposition of the loop entropy factor into a sum of I exponential functions (1) gives an extremely accurate approximation to the loop entropy factor for small values of I and (2) makes the computer time for the exact algorithms proportional to I·N. In effect, exact results for melting curves and lengths of helix or coil stretches are obtained with computer time comparable to that required for the Frank-Kamenetskii approximation. The remarkable accuracy of the latter for the fraction of helical content (errors of 0.01–0.05) is confirmed, but appreciably larger errors are found for the lengths of helix or coil stretches (typical errors of 30–100%). 相似文献
854.
855.
Anderson Odon Carolina A. Freire R. Mark Brigham Marcelo O. Bordignon Emygdio L. A. Monteiro-Filho 《Biotropica》2023,55(3):573-578
Torpor and hibernation are energy-saving heterothermic strategies widespread among mammals, and bats have reports of hibernation in North America, Europe, Asia, Oceania, and Africa. However, to date, there was no evidence of hibernation by bats in South America. We tagged four individuals of Eptesicus brasiliensis and one remained torpid for 13 consecutive days in a tree cavity roost in southern Brazil, showing evidence that bats can hibernate in South America. 相似文献
856.
857.
Antonio G. González Raimundo Freire Rosendo Hernández Jost A. Salazar Ernesto Suárez 《Phytochemistry》1973,12(11):2733-2735
From stems and leaves of Semele androgyna L. the new steroid sapogenin 25S-dihydrodracogenin (Ia) has been isolated and its structure confirmed by conversion into the acetates of 25R-dihydrosansevierigenin (Id) and ruscogenin (If) and by partial hydrogenation of dracogenin. 相似文献
858.
859.
Oren Feine Elvira Hukasova Wytse Bruinsma Raimundo Freire Abraham Fainsod Julian Gannon 《Cell cycle (Georgetown, Tex.)》2014,13(11):1727-1736
Cdk1 and Plk1/Plx1 activation leads to their inactivation through negative feedback loops. Cdk1 deactivates itself by activating the APC/C, consequently generating embryonic cell cycle oscillations. APC/C inhibition by the mitotic checkpoint in somatic cells and the cytostatic factor (CSF) in oocytes sustain the mitotic state. Plk1/Plx1 targets its co-activator Bora for degradation, but it remains unclear how embryonic oscillations in Plx1 activity are generated, and how Plk1/Plx1 activity is sustained during mitosis. We show that Plx1-mediated degradation of Bora in interphase generates oscillations in Plx1 activity and is essential for development. In CSF extracts, phosphorylation of Bora on the Cdk consensus site T52 blocks Bora degradation. Upon fertilization, Calcineurin dephosphorylates T52, triggering Plx1 oscillations. Similarly, we find that GFP-Bora is degraded when Plk1 activity spreads to somatic cell cytoplasm before mitosis. Interestingly, GFP–Bora degradation stops upon mitotic entry when Cdk1 activity is high. We hypothesize that Cdk1 controls Bora through an incoherent feedforward loop synchronizing the activities of mitotic kinases. 相似文献
860.
Calorimetric determination of cooperative interactions in high affinity binding processes 总被引:1,自引:0,他引:1
It is demonstrated that isothermal titration calorimetry can be used to determine cooperative interaction energetics even for extremely tight binding processes in which the binding affinity constants are beyond the limits of experimental determination. The approach is based on the capability of calorimetry to measure the apparent binding enthalpy at any degree of ligand saturation. When calorimetric measurements are performed under conditions of total association at partial saturation, the dependence of the apparent binding enthalpy on the degree of saturation is a function only of the cooperative binding interactions. The method developed in this paper allows an independent estimation of cooperative energetic parameters without the need to simultaneously estimate or precisely know the value of the association constants. Since total ligand association at partial saturation is achieved only at macromolecular concentrations much larger than the dissociation constants, the method is especially suited for high and very high affinity processes. Biological associations in this category include fundamental cellular processes like cell surface receptor binding or protein-DNA interactions. 相似文献