Barriers and opportunities for adapting to climate change on the North Coast of São Paulo,Brazil

Regional Environmental Change - This paper examines barriers and opportunities for climate change adaptation in an urban coastal setting where adaptation is in its infancy. It draws on a diagnostic...     

Assessment of mammal reproduction for hunting sustainability through community‐based sampling of species in the wild

Wildlife subsistence hunting is a major source of protein for tropical rural populations and a prominent conservation issue. The intrinsic rate of natural increase. (r_max) of populations is a key reproductive parameter in the most used assessments of hunting sustainability. However, researchers face severe difficulties in obtaining reproductive data in the wild, so these assessments often rely on classic reproductive rates calculated mostly from studies of captive animals conducted 30 years ago. The result is a flaw in almost 50% of studies, which hampers management decision making. We conducted a 15‐year study in the Amazon in which we used reproductive data from the genitalia of 950 hunted female mammals. Genitalia were collected by local hunters. We examined tissue from these samples to estimate birthrates for wild populations of the 10 most hunted mammals. We compared our estimates with classic measures and considered the utility of the use of r_max in sustainability assessments. For woolly monkey (Lagothrix poeppigii) and tapir (Tapirus terrestris), wild birthrates were similar to those from captive populations, whereas birthrates for other ungulates and lowland‐paca (Cuniculus paca) were significantly lower than previous estimates. Conversely, for capuchin monkeys (Sapajus macrocephalus), agoutis (Dasyprocta sp.), and coatis (Nasua nasua), our calculated reproductive rates greatly exceeded often‐used values. Researchers could keep applying classic measures compatible with our estimates, but for other species previous estimates of r_max may not be appropriate. We suggest that data from local studies be used to set hunting quotas. Our maximum rates of population growth in the wild correlated with body weight, which suggests that our method is consistent and reliable. Integration of this method into community‐based wildlife management and the training of local hunters to record pregnancies in hunted animals could efficiently generate useful information of life histories of wild species and thus improve management of natural resources.     

Chemometric tools applied to optimize a fast solid-phase microextraction method for analysis of polycyclic aromatic hydrocarbons in produced water

Environmental Science and Pollution Research - Chemometric tools are powerful strategies to efficiently optimize many processes. These tools were employed to optimize a fast-solid phase...     

Voltammetric analysis of metallothioneins and copper (II) in fish for water biomonitoring studies

An major research area in environmental chemistry is the development of methods for the analysis of biomarkers. Metallothioneins are used as biomarkers in studies of heavy metals exposure in water, because metallothioneins are synthesized and accumulated when organisms are exposed to toxic concentrations of pollutants. In this work, simple and sensitive voltammetric methods were developed for metallothionein and copper (II) determinations in fish liver Lepomis gibbosus. Both analytical methodologies were optimized and applied to samples extracted from individuals previously submitted to sub-lethal toxicological trials with copper sulphate (CuSO₄) and cadmium chloride (CdCl₂). The obtained results showed that both methods are very precise, sensitive, and involve simple sample preparation processes. Moreover, metallothioneins showed better correlation with the toxic exposure than Cu²⁺. To the best of our knowledge, this is the first time that hepatic metallothioneins and Cu²⁺ contents are voltammetrically determined in order to be compared in their function as heavy metal biological indicators.     

Changes in glucose uptake rate and in the energy status of PC-12 cells acutely exposed to hexavalent chromium,an established human carcinogen

In the 1920s, Otto Warburg reported a striking metabolic shift in solid tumors: contrary to their normal counter parts, which exhibited a nearly pure respiratory metabolism, where cancer cells relied strongly on lactic fermentation for energy production, even in the presence of ample oxygen. This metabolic shift, later named the Warburg effect, is now viewed as a nearly universal cancer phenotype. To investigate whether it is operating in hexavalent chromium (Cr(VI))-induced carcinogenesis, PC-12 cells were exposed to low Cr(VI) concentrations and effects determined on the rates of glucose uptake, lactate production and oxygen consumption, critical indicators of the type of energy metabolism adopted by the cells. Further, the influence on the cells’ energy charge, an important parameter in the evaluation of the cellular physiological state was assessed. In the presence of ample oxygen, concentration-dependent, statistically significant decreases in the energy charge were detected, which were accompanied by an increased glucose uptake rate. This enhanced uptake may constitute the first step in a compensatory mechanism aimed at counteracting the decrease in energy charge. Although these changes may be too small to exert an impact in the cellular functions, they may provide insight into the initial steps of Cr(VI)-induced carcinogenesis.     

Terpenylnaphthoquinones are reductively activated by NADH/NADH dehydrogenase

Novel terpenylnaphthoquinones were found to enhance the rate of oxygen consumption in the presence of NADH/NADH dehydrogenase in 1?:?1?v/v mixtures of 40?mM phosphate buffer (pH 7.4) and DMSO. Initial rates of oxygen consumption increase with an increase in the half-wave reduction potentials of the quinones. The amounts of spin trapped methyl radicals in the presence of DMSO, produced through the Haber–Weiss reaction of the oxygen consumption process, and of the corresponding semiquinones, generated under anaerobic conditions, also correlate with the quinone redox potential. Since this enzymatic system is found in mitochondria, a possible pathway in the cytotoxic activity of these terpenylnaphthoquinones could be the interference or inhibition of mitochondrial respiration by NADH depletion or by mitochondrial degradation due to reactive oxygen species generation.     

An approach to simulate wind fields around an urban environment for wind energy application

This work proposes an approach to simulate wind flow fields around an urban environment with the aim of evaluating the potential impact of buildings on the general wind patterns and power production using the current generation of commercial wind turbines. The simulation process was performed with the aid of accessible computational tools that can potentially render the proposed procedure applicable in other cases of interest. The roughness of the urban environment was defined as the association of roughness map, topography, and an alternative process for obtaining the volumetry of buildings. A case study was conducted in a region located at the district of Boa Viagem (Recife-PE) for assessing the applicability of the approach. Scenarios were designed in order to simulate wind flow patterns and pre-identify sites that have suitable wind energy potential for electric power production by investigating the combination of wind speed magnitude and turbulence intensity. From the results obtained, it was possible to identify zones of potential wind sources that are not detected in classical wind atlas probably due to the influence of the built environment on local wind flow patterns.     

The surgeonfish, Acanthurus bahianus, has crossed the Amazon–Orinoco outflow barrier

Dispersal varies among species according to different biological and environmental factors. It is known that there is strong genetic division between the Ocean Surgeonfish (Acanthurus tractus) and the Barber Surgeonfish (Acanthurus bahianus) in the Caribbean and southern Atlantic biogeographic provinces with relation to the Amazon–Orinoco outflows. We analyzed cytb gene sequence diversity from 149 individuals collected at five localities around Cuba between October 2006 and February 2010. As expected, most individuals had haplotypes identical or closely related to those previously reported for the Caribbean. However, south Atlantic lineage haplotypes were also found in all surveyed localities with frequencies around 5 %. This finding suggests that A. bahianus has dispersed in recent times across the Amazon–Orinoco barrier, probably because environmental perturbations have aided dispersal.