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Juan Carlos Yugar-Toledo,1 Rodrigo Modolo,2 Ana Paula de Faria,2 Heitor Moreno2 1São José do Rio Preto Medicine School – FAMERP, São José do Rio Preto, 2School of Medical Sciences, University of Campinas (UNICAMP), Campinas, Brazil Abstract: Mineralocorticoid-receptor antagonists (MRAs) have proven to be effective in some types of hypertension, especially in resistant hypertension (RHTN). In this phenotype of hypertension, the renin–angiotensin–aldosterone pathway plays an important role, with MRAs being especially effective in reducing blood pressure. In this review, we show the relevance of aldosterone in RHTN, as well as some clinical characteristics of this condition and the main concepts involving its pathophysiology and cardiovascular damage. We analyzed the mechanisms of action and clinical effects of two current MRAs – spironolactone and eplerenone – both of which are useful in RHTN, with special attention to the former. RHTN represents a significant minority (10%–15%) of hypertension cases. However, primary-care physicians, cardiologists, nephrologists, neurologists, and geriatricians face this health problem on a daily basis. MRAs are likely one of the best pharmacological options in RHTN patients; however, they are still underused. Keywords: resistant hypertension, aldosterone, aldosteronism, mineralocorticoid-receptor antagonists, spironolactone, eplerenone

Se describen las características morfológicas de las semillas y las plántulas de nazareno (Peltogyne paniculata), peinemono (Apeiba membranacea Spruce ex Benth), sapán (Clathotropis brachypetala (Tul.) Kleinh.), sota amarilla (Virola sebífera) y sota negra (Virola flexuosa A.C. Sm.). También se incluyen algunas observaciones y revisión de literatura sobre otros aspectos de la biología reproductiva de estas especies, el hábitat, la descripción taxonómica y los usos.

Se describen las características morfológicas de las semillas y plántulas de abarco (Cariniana pyriformis), almendrón (Caryocar glabrum), cabuyo (Eschweilera cf. reticulata), chingalé (Jacaranda copaia) y fresno (Tapirira guianensis). También se incluyen algunas observaciones y revisión de literatura sobre otros aspectos de la biología reproductiva de estas especies, el hábitat, la descripción taxonómica y los usos.

Termites are important ecosystem engineers in tropical habitats, with different feeding groups able to decompose wood, grass, litter, and soil organic matter. In most tropical regions, termite abundance and species diversity are assumed to increase with rainfall, with highest levels found in rainforests. However, in the Australian tropics, this pattern is thought to be reversed, with lower species richness and termite abundance found in rainforest than drier habitats. The potential mechanisms underlying this pattern remain unclear. We compared termite assemblages (abundance, activity, diversity, and feeding group composition) across five sites along a precipitation gradient (ranging from ∼800 to 4,000 mm annual rainfall), spanning dry and wet savanna habitats, wet sclerophyll, and lowland and upland rainforests in tropical North Queensland. Moving from dry to wet habitats, we observed dramatic decreases in termite abundance in both mounds and dead wood occupancy, with greater abundance and activity at savanna sites (low precipitation) compared with rainforest or sclerophyll sites (high precipitation). We also observed a turnover in termite species and feeding group diversity across sites that were close together, but in different habitats. Termite species and feeding group richness were highest in savanna sites, with 13 termite species from wood-, litter-, grass-, dung-, and soil-feeding groups, while only five termite species were encountered in rainforest and wet sclerophyll sites—all wood feeders. These results suggest that the Australian termite diversity anomaly may be partly driven by how specific feeding groups colonized habitats across Australia. Consequently, termites in Australian rainforests may be less important in ecosystem processes, such as carbon and nutrient cycling during decomposition, compared with termites in other tropical rainforests.

Objetivo: Evaluar los variables que influyen de manera Importante en la presión del neumotaponador en pacientes intubados en la UCI del HSJD. Diseño: Estudio retrospectivo de 76 mediciones en 16 pacientes ventilados mecánicamente. Mediciones: Durante las dos fases del ciclo respiratorio se midieron: presión máxima del neumotaponador al final de lo fase inspiradora (PNI). presión máxima del neumotaponador al final de la fase espiradora (PNE), el volumen con el cual se Insuflaba el neumotaponador hasta evitar el escape de aire (VN). Se tuvo en cuenta también el calibre del tubo (TUBCAT). Igualmente se registraron la presión inspiratoria máxima generada por el ventilador (PIM) y la presión positiva al final de la espiración (PEEP).

We have investigated the Ni magnetic alignment when deposited on the CrN (111) magnetic surface and the possible growth of NiN and Ni4N on this surface using first principles calculations. The results revealed that when Ni substituted the Cr atoms of the outermost layer, a switching in the magnetic arrangement, from ferromagnetic to antiferromagnetic, takes place. We have used the surface formation energy (SFE) formalism to establish the thermodynamic stability to study the growth of these nickel nitrides. According to the results, NiN growth yields the formation of only 2 bilayers under N-rich conditions; in contrast, Ni4N may grow on the CrN (111) substrate. To confirm the stability, ab initio molecular dynamics (AIDM) calculations were performed at 80 K and 300 K; moreover, different strains have been considered in the studies. Our results suggest that the Ni4N (111) surface may form with a strain substrate up to 6% at low temperatures and below; the compound is stable at room temperature. Beyond this strain, the structure showed a non-crystalline array. In addition, the SFE demonstrated that the N-terminated surface is the most stable configuration under Ni-rich conditions, for example, at 20% N2 flux. These facts agree well with the experimental data. The magnetic anisotropic energy (MAE) of the NiN structure showed that the Ni spins are pinned to the easy magnetization axis of the CrN (111) surface, and its electronic properties exhibit a metallic character. [ABSTRACT FROM AUTHOR]

The coherent elastic scattering of neutrinos off nuclei has eluded detection for four decades, even though its predicted cross section is by far the largest of all low-energy neutrino couplings. This mode of interaction offers new opportunities to study neutrino properties and leads to a miniaturization of detector size, with potential technological applications. We observed this process at a 6.7σ confidence level, using a low-background, 14.6-kilogram CsI[Na] scintillator exposed to the neutrino emissions from the Spallation Neutron Source at Oak Ridge National Laboratory. Characteristic signatures in energy and time, predicted by the standard model for this process, were observed in high signal-to-background conditions. Improved constraints on nonstandard neutrino interactions with quarks are derived from this initial data set.