Vulnerabilidad climática de Puerto Iguazú, Argentina: Camino hacia la adaptación

Las ciudades ocupan un papel vital en el combate contra el cambio climático. Su importancia como actores esenciales se basa en el hecho de que concentran gran parte de la actividad económica y se espera que alberguen a dos terceras partes de la población del planeta para mediados de siglo. En este sentido, las acciones que las ciudades pueden realizar para enfrentar este desafío son significativas. Estas acciones incluyen esfuerzos para mitigar los efectos adversos del calentamiento global, así como gestiones para protegerse y adaptarse a eventos climáticos extremos, los cuales es probable que se tornen más intensos y frecuentes en un futuro. Hasta el momento, la atención se ha volcado predominantemente hacia las grandes metrópolis, dejando a un lado las ciudades medianas y pequeñas, las cuales a menudo son las que registran los niveles de crecimiento más altos y las que carecen de recursos de diversa índole para hacer frente a este desafío. Bajo este contexto, el presente artículo se enfoca a examinar la vulnerabilidad climática de Puerto Iguazú, una ciudad argentina situada en la llamada región de la "Triple Frontera", ya que comparte límites territoriales con Ciudad del Este (Paraguay) y Foz do Iguaçu (Brasil). El análisis se base en un enfoque de métodos mixtos. En términos cuantitativos, se desarrolló un Índice de Vulnerabilidad Urbana (IVU), el cual incluye 73 indicadores económicos, sociales, físicos, climáticos y ambientales, con el propósito de cuantificar la sensitividad de la ciudad a eventos climáticos extremos, así como su capacidad para responder y adaptarse. En términos cualitativos, información derivada de entrevistas fue utilizada para complementar los hallazgos. Este estudio forma parte de la iniciativa Ciudades Resilientes al Clima (CRC) en América Latina. El artículo, en este sentido, también hace una reflexión sobre la experiencia de conducir un proyecto bajo dicha iniciativa, y sobre las lecciones que estos resultados ofrecen a otras ciudades en contextos similares en América Latina

Involvement of the basal cholinergic forebrain in the mediation of general (Propofol) anesthesia:

BACKGROUND: Recent studies have pointed out the involvement of the basal forebrain gamma-aminobutyric acid-mediated system in mediating the effects of general anesthesia. In this study, the authors asked whether the basal forebrain cholinergic system is also involved in mediating the effects of general anesthetics such as propofol. METHODS: Cholinergic lesions were produced by administration of the selective immunotoxin 192 immunoglobulin G-saporin into the lateral ventricles, the medial septum, or the nucleus basalis magnocellularis. The anesthetic potency of propofol was determined using an anesthetic score with a crossover counterbalanced design. Animals were given intraperitoneal propofol (25 or 50 mg/kg) repeatedly every 15 min to set up a subanesthetic (low-dose) or anesthetic (high-dose) state. The anesthetic score was assessed for each cumulative dose. Control of the cholinergic depletion was performed using histochemical acetylcholinesterase staining on brain slices. RESULTS: A shift from a subanesthetic state to an anesthetic state was observed mainly in the rats with the immunotoxin injected into the lateral ventricles or the medial septum and vertical diagonal band of Broca, compared with controls. In those rats, the density of acetylcholinesterase reaction products was normal in the striatum and the thalamus, but reduced in the cortex and the hippocampus. CONCLUSION: The anesthetic potency of propofol was increased in all rats with hippocampal lesions, whatever the injection sites, compared with controls. These results demonstrate that a cholinergic dysfunction in the basal forebrain potentiates the anesthetic effects of propofol

First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data

Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signalto- noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars over a fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of 11 pulsars using data from Advanced LIGO’s first observing run. Although we have found several initial outliers, further studies show no significant evidence for the presence of a gravitational wave signal. Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of the 11 targets over the bands searched; in the case of J1813-1749 the spin-down limit has been beaten for the first time. For an additional 3 targets, the median upper limit across the search bands is below the spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried out so far

All-sky search for periodic gravitational waves in the O1 LIGO data

We report on an all-sky search for periodic gravitational waves in the frequency band 20-475 Hz and with a frequency time derivative in the range of [-1.0,+0.1]×10-8 Hz/s. Such a signal could be produced by a nearby spinning and slightly nonaxisymmetric isolated neutron star in our galaxy. This search uses the data from Advanced LIGO\u27s first observational run, O1. No periodic gravitational wave signals were observed, and upper limits were placed on their strengths. The lowest upper limits on worst-case (linearly polarized) strain amplitude h0 are ∼4×10-25 near 170 Hz. For a circularly polarized source (most favorable orientation), the smallest upper limits obtained are ∼1.5×10-25. These upper limits refer to all sky locations and the entire range of frequency derivative values. For a population-averaged ensemble of sky locations and stellar orientations, the lowest upper limits obtained for the strain amplitude are ∼2.5×10-25

The Beta-decay Paul Trap Mk IV: Design and commissioning

The Beta-decay Paul Trap is an open-geometry, linear trap used to measure the decays of $^8$Li and $^8$B to search for a tensor contribution to the weak interaction. In the latest $^8$Li measurement of Burkey et al. (2022), $\beta$ scattering was the dominant experimental systematic uncertainty. The Beta-decay Paul Trap Mk IV reduces the prevalence of $\beta$ scattering by a factor of 4 through a redesigned electrode geometry and the use of glassy carbon and graphite as electrode materials. The trap has been constructed and successfully commissioned with $^8$Li in a new data campaign that collected 2.6 million triple coincidence events, an increase in statistics by 30% with 4 times less $\beta$ scattering compared to the previous $^8$Li data set.Comment: 17 pages, 7 figure

Negative priming and occasion setting in an appetitive Pavlovian procedure

Rats received training in which two auditory target stimuli, X and Y, were signaled by two visual stimuli, A and B, and followed by food (i.e., A→X1, B→Y+). The test consisted of presentations of X and Y preceded either by the same signal as during training (same trials: A→X, B→Y) or by the alternative signal (different trials: A→Y, B→X). After 8 training sessions, the animals responded less on same trials than on different trials; this effect was significantly reduced after 24 training sessions. In two additional experiments, animals that had also experienced presentations of A and B alone, either before or during training, showed the opposite pattern of results, responding more on same trials than on different trials. These results are interpreted as being due to the interaction between the effects of occasion setting andnegative priming (see Wagner, 1981)

Endothelial Stomatal and Fenestral Diaphragms in Normal Vessels and Angiogenesis

Vascular endothelium lines the entire cardiovascular system where performs a series of vital functions including the control of microvascular permeability, coagulation inflammation, vascular tone as well as the formation of new vessels via vasculogenesis and angiogenesis in normal and disease states. Normal endothelium consists of heterogeneous populations of cells differentiated according to the vascular bed and segment of the vascular tree where they occur. One of the cardinal features is the expression of specific subcellular structures such as plasmalemmal vesicles or caveolae, transendothelial channels, vesiculo-vacuolar organelles, endothelial pockets and fenestrae, whose presence define several endothelial morphological types. A less explored observation is the differential expression of such structures in diverse settings of angiogenesis. This review will focus on the latest developments on the components, structure and function of these specific endothelial structures in normal endothelium as well as in diverse settings of angiogenesis