Spatio-Temporal Determination of Small-Scale Vessels’ Fishing Grounds Using a Vessel Monitoring System in the Southeastern Gulf of Mexico

In most small-scale fisheries (SSF), there is limited or null information about the distribution and spatial extent of the fishing grounds where the fleets operate, due to the lack of explicit spatial and temporal data. This information is key when addressing marine spatial planning and fisheries management programs for SSF. In addition to technical or biogeographic restrictions, environmental conditions in the area influence the way fishers operate. Making use of data from a pilot Vessel Monitoring System (VMS) project tested in a small-scale fleet in the Southeastern Gulf of Mexico (SGoM), for the first time in the region, we were able to learn what role environmental factors play in the distribution of potential fishing grounds for this fleet. We got tracking information of 1,608 daily fishing trips from vessels operating in four states using the VMS for 7 months. We used a correlative modeling approach to identify potential fishing grounds where this fleet operates along the SGoM, accounting for environmental variables. We assumed that environmental conditions can shape the spatial distribution of species targeted by this fleet and hence influence fishers’ operations. The results indicated that net primary production and sea surface temperature were the main drivers that shape the spatio-temporal potential distribution of fishing grounds in the study site. The approach employed here seems appropriated and opens an opportunity to learn more about the factors that define the spatial distribution of small-scale fleets and their potential fishing grounds

Use of Mesenchymal Stem Cells in Pre-Clinical Models of Spinal Cord Injury

Spinal Cord Injury (SCI) is a devastating disease that causes disruption of sensorimotor function below the site of injury. Current management is based on surgical decompression of the neural tissue and pharmacotherapy; however, there is no gold standard treatment readily available for patients in the clinic. This indicates that novel therapeutic strategies for the treatment are still needed in the clinical setting. There are several alternatives that are currently under investigation for the treatment of this disease, with increasing focus in regenerative medicine treatments. Mesenchymal stem cells (MSCs) are one of the most promising candidates for stem cell therapy in SCI, as they are easily obtained, have high safety profiles, and help with neural regeneration in SCI mainly via release of trophic factors, neovascularization, and immunomodulation. In this work, authors provide an insight of the available MSC for neural regeneration, their therapeutic role, and the potential MSC-based therapies for SCI

Burden of childhood-onset arthritis

Juvenile arthritis comprises a variety of chronic inflammatory diseases causing erosive arthritis in children, often progressing to disability. These children experience functional impairment due to joint and back pain, heel pain, swelling of joints and morning stiffness, contractures, pain, and anterior uveitis leading to blindness. As children who have juvenile arthritis reach adulthood, they face possible continuing disease activity, medication-associated morbidity, and life-long disability and risk for emotional and social dysfunction. In this article we will review the burden of juvenile arthritis for the patient and society and focus on the following areas: patient disability; visual outcome; other medical complications; physical activity; impact on HRQOL; emotional impact; pain and coping; ambulatory visits, hospitalizations and mortality; economic impact; burden on caregivers; transition issues; educational occupational outcomes, and sexuality

Variable Fitness Impact of HIV-1 Escape Mutations to Cytotoxic T Lymphocyte (CTL) Response

Human lymphocyte antigen (HLA)-restricted CD8+ cytotoxic T lymphocytes (CTL) target and kill HIV-infected cells expressing cognate viral epitopes. This response selects for escape mutations within CTL epitopes that can diminish viral replication fitness. Here, we assess the fitness impact of escape mutations emerging in seven CTL epitopes in the gp120 Env and p24 Gag coding regions of an individual followed longitudinally from the time of acute HIV-1 infection, as well as some of these same epitopes recognized in other HIV-1-infected individuals. Nine dominant mutations appeared in five gp120 epitopes within the first year of infection, whereas all four mutations found in two p24 epitopes emerged after nearly two years of infection. These mutations were introduced individually into the autologous gene found in acute infection and then placed into a full-length, infectious viral genome. When competed against virus expressing the parental protein, fitness loss was observed with only one of the nine gp120 mutations, whereas four had no effect and three conferred a slight increase in fitness. In contrast, mutations conferring CTL escape in the p24 epitopes significantly decreased viral fitness. One particular escape mutation within a p24 epitope was associated with reduced peptide recognition and high viral fitness costs but was replaced by a fitness-neutral mutation. This mutation appeared to alter epitope processing concomitant with a reduced CTL response. In conclusion, CTL escape mutations in HIV-1 Gag p24 were associated with significant fitness costs, whereas most escape mutations in the Env gene were fitness neutral, suggesting a balance between immunologic escape and replicative fitness costs

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Geogebra y Problemas de Optimización

El siguiente trabajo muestra una propuesta para la enseñanza del cálculo diferencial con el uso del software Geogebra como herramienta didáctica en el aprendizaje de la derivada con problemas de optimización. El artículo contiene dos actividades en las cuales se explotan las cualidades gráficas, numéricas y algebraicas del software para analizar la variación y el concepto de derivada, y al final queda de manifiesto que el uso adecuado de las distintas representaciones semióticas de un concepto matemático ayuda a una mejor comprensión del mismo