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

Bycatch species composition over time by tuna purse-seine fishery in the eastern tropical Atlantic Ocean.

Post-print

Consenso Mexicano para el Tratamiento de la Hepatitis C

El objetivo del Consenso Mexicano para el Tratamiento de la Hepatitis C fue el de desarrollar un documento como guía en la práctica clínica con aplicabilidad en México. Se tomó en cuenta la opinión de expertos en el tema con especialidad en: gastroenterología, infectología y hepatología. Se realizó una revisión de la bibliografía en MEDLINE, EMBASE y CENTRAL mediante palabras claves referentes al tratamiento de la hepatitis C. Posteriormente se evaluó la calidad de la evidencia mediante el sistema GRADE y se redactaron enunciados, los cuales fueron sometidos a voto mediante un sistema modificado Delphi, y posteriormente se realizó revisión y corrección de los enunciados por un panel de 34 votantes. Finalmente se clasificó el nivel de acuerdo para cada oración. Esta guía busca dar recomendaciones con énfasis en los nuevos antivirales de acción directa y de esta manera facilitar su uso en la práctica clínica. Cada caso debe ser individualizado según sus comorbilidades y el manejo de estos pacientes siempre debe ser multidisciplinario. Abstract The aim of the Mexican Consensus on the Treatment of Hepatitis C was to develop clinical practice guidelines applicable to Mexico. The expert opinion of specialists in the following areas was taken into account: gastroenterology, infectious diseases, and hepatology. A search of the medical literature was carried out on the MEDLINE, EMBASE, and CENTRAL databases through keywords related to hepatitis C treatment. The quality of evidence was subsequently evaluated using the GRADE system and the consensus statements were formulated. The statements were then voted upon, using the modified Delphi system, and reviewed and corrected by a panel of 34 voting participants. Finally, the level of agreement was classified for each statement. The present guidelines provide recommendations with an emphasis on the new direct-acting antivirals, to facilitate their use in clinical practice. Each case must be individualized according to the comorbidities involved and patient management must always be multidisciplinary

Changes in fishing power and fishing strategies driven by new technologies : the case of tropical tuna purse seiners in the eastern Atlantic Ocean

Technological advancements can influence both the fishing power of a fleet and the fishing strategies itemploys. To investigate these potential linkages, we examined almost three decades of data (1981–2008)from French tropical tuna purse seiners operating in the eastern Atlantic Ocean. Applying a sequence ofstatistical methods at different temporal and spatial scales, we analyzed two indicators of fishing power(sets per boat-day on fish aggregating devices (FADs) and sets per boat-day on free-swimming schools)each of which represent a distinct fishing mode. Our results show that the increasing modernizationof this fleet has led to increases in both fishing power and the available number of fishing strategies tochoose from. A key output of this analysis was the breakdown of fishing power time series (for each fishingmode) into separate periods of continuous years during which catchability was assumed to be constant,thus identifying regime shifts. This partitioning allowed us to identify when key changes occurred inthe fishery. Changes in FAD-associated fishing were mostly driven by the introduction of radio beacons(early 1990s) which lead to an increase in fishing effort and an expansion of fishing grounds (directeffect) and the implementation of time-area management measures which resulted in a fragmentationof the traditional fishing grounds in the 2000s (indirect effect). During the same period, fishing on free-swimming schools also increased despite the biomass of stocks decreasing and fishing grounds remainingunchanged. This suggests these increases were driven by improvements in fish detection technology (e.g.,bird radars, sonar). These identified increases are not entirely unexpected: indeed it is widely recognizedthat fishing power in the purse seine tuna fishery has increased over time. However, these increases donot necessarily occur linearly. Thus, understanding how fishing power is changing over time (such asdetermining when regime shifts occur) is critical to improving the CPUE standardization procedure intropical tuna purse seine fisheries

Determination of the soil moisture recession constant from satellite data: a case study of the Yucatan peninsula

Estimation of the recession constant for soil moisture can assist in soil and water management. This article estimates soil moisture recession velocity from satellite data, thereby taking advantage of extensive data coverage in a metric that is more commonly used with point data for rivers. Retrieval from satellites of the surface soil moisture has produced global coverage of multiannual time series data, thereby allowing the application of techniques that require long time series of daily data. We applied two techniques from river hydrology to soil moisture data from the advanced scatterometer aboard the meteorological operational satellite: (1) baseflow separation; and (2) master recession curve (MRC) with the correlation method. The former filtered the data and extracted those for the base soil moisture (BSM), which is considered the water that circulates in the soil by capillarity. The latter technique allowed the estimation of recession constants by the extraction of continuously decreasing BSM segments. The use of MRC for a large range of BSM provides a recession constant representative of all the moisture decrease for each pixel, thereby permitting the identification of drought-sensitive zones. The recession constant, a metric that had not been used for soil moisture, allowed us to determine potential temporal evolution of drought in the Yucatan peninsula. Government agencies could use the approach applied in this study to improve water management and drought prevention

Influence of ZrO2 nanoparticles and thermal treatment on the properties of PMMA/ZrO2 hybrid coatings

In this work, ZrO2 nanoparticles were synthesized by the sol-gel method, treated thermally at different temperatures (400, 600 and 800 °C), and added to a polymer matrix in two different weight percentages (0.5 and 1) by single screw extrusion in order to determine the influence of these parameters on the thermal stability and UV radiation resistance of PMMA/ZrO2 composites. Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), X-ray diffraction (XRD), transmission electron microscopy (TEM), confocal laser scanning microscopy (CLSM), ultraviolet-visible spectroscopy (UV-Vis), thermogravimetric analysis (TGA) and nanoindentation techniques were used to evaluate the structural, morphological, optical, thermal and mechanical properties of as-prepared composites. The average crystallite sizes for ZrO2 sintered at 600 and 800 °C were about 17 and 26 nm, respectively. It was found that the incorporation of a low percentage of ZrO2 nanoparticles increased the thermal properties of PMMA as well as its hardness and elastic modulus. The degradation temperature at 10 wt.% loss of the PMMA/ZrO2 (0.5 wt.%, 400 °C) nanocomposite was approximately 48 °C higher than that of pure PMMA. The absorption in the UV region was increased according to the ZrO2 heat treatment temperature and amount added to the polymer matrix. © 2014 Elsevier B.V. All rights reserved