Semen quality as a potential susceptibility indicator to SARS-CoV-2 insults in polluted areas

Environmental Science and Pollution Research - The epidemic of the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has impacted worldwide with its infectious spread and mortality...     

A comparison of strike and prey capture kinematics of three species of piscivorous fishes: Florida gar ( Lepisosteus platyrhincus), redfin needlefish ( Strongylura notata), and great barracuda ( Sphyraena barracuda)

Ram feeding is the process by which a predatory fish uses a high-velocity lunge or chase to overtake its prey. This study compares the strike and prey capture behaviors and kinematics of three species of ram-feeding fishes: Florida gar Lepisosteus platyrhincus, redfin needlefish Strongylura notata, and great barracuda Sphyraena barracuda. These ram-feeding piscivores are morphologically similar with fusiform bodies, posteriorly placed dorsal and anal fins, and large, conical teeth. Strike and prey capture kinematics for five individuals of each species were recorded with high-speed video. Pre-strike behavior in L. platyrhincus consists of a slow stalk, resulting in the close, lateral positioning of the predators head relative to the prey. Lepisosteus employ a sideways lunge of the head during the strike, which lasts only 25–40 ms and is the most rapid strike among these three species. Strongylura notata and Sphyraena barracuda exhibit longitudinal orientation to the prey before the strike, followed by a high velocity, head-on lunge, initiated by an s-start in Sphyraena barracuda. Prey capture in adult L. platyrhincus and Strongylura notata is characterized by the jaws closing on the prey, with the prey held orthogonal to the jaws. This is followed by manipulation using the inertia of the prey to reposition the prey head first, and then suction transport into the buccal cavity. Prey capture in juvenile Sphyraena is accomplished by closing the jaws after the prey has entered the buccal cavity, resulting in possible ram transport of the prey with no oral manipulation under these experimental conditions. Although these three species all employ ram feeding for prey capture of elusive prey, each species has a unique repertoire that appears to minimize hydrodynamic constraints and prey response, utilize locomotory capabilities, and may be suited to each species specific habitat.Communicated by P.W. Sammarco, Chauvin     

The neglected burden of agricultural intensification: a contribution to the debate on land-use change

ABSTRACT

Between 1992 and 2015 Argentina lost 17% of its tree cover. Regionally, deforestation continues, but net forest loss recently came to a halt. Some scholars argue that this was facilitated by industrial agricultural intensification. This view is debated, but we focus on the neglected costs associated with this intensification. An almost tenfold increase of pesticide use in Argentina during the last two decades caused the pollution of soil, water and sediments. The widespread use of pesticides is impairing the health of agricultural workers and people living near agricultural fields, and is putting the health of vulnerable parts of the population (children and pregnant women) at risk. More than 50 pesticide active ingredients marketed in Argentina have been banned in the European Union for safety reasons. We contend that health and pollution aspects need to be taken into account when assessing the benefits and drawbacks of different types of land use.     

Stable carbon isotope ratio in atmospheric CO2 collected by new diffusive devices

In this paper, stable carbon isotope ratios (δ ¹³C) were determined in the atmosphere by using a Ca-based sorbent, CaO/Ca₁₂Al₁₄O₃₃ 75:25 w/w, for passively collecting atmospheric CO₂, in both field and laboratory experiments. Field measurements were conducted in three environments characterized by different carbon dioxide sources. In particular, the environments under consideration were a rather heavily trafficked road, where the source of CO₂ is mostly vehicle exhaust, a rural unpolluted area, and a private kitchen where the major source of CO₂ was gas combustion. Samplers were exposed to the free atmosphere for 3 days in order to allow collection of sufficient CO₂ for δ¹³C analysis, then the collected CO₂ was desorbed from the adsorbent with acid treatment, and directly analyzed by nondispersive infrared (NDIR) instrument. δ ¹³C results confirmed that the samplers collected representative CO₂ samples and no fractionation occurred during passive trapping, as also confirmed by an appositely designed experiment conducted in the laboratory. Passive sampling using CaO/Ca₁₂Al₁₄O₃₃ 75:25 w/w proved to be an easy and reliable method to collect atmospheric carbon dioxide for δ ¹³C analysis in both indoor and outdoor places.     

Local ecological knowledge and incremental adaptation to changing flood patterns in the Amazon delta

The need for understanding the factors that trigger human responses to climate change has opened inquiries on the role of indigenous and local ecological knowledge (ILK) in facilitating or constraining social adaptation processes. Answers to the question of how ILK is helping or limiting smallholders to cope with increasing disturbances to the local hydro-climatic regime remain very limited in adaptation and mitigation studies and interventions. Herein, we discuss a case study on ILK as a resource used by expert farmer-fishers (locally known as Caboclos) to cope with the increasing threats on their livelihoods and environments generated by changing flood patterns in the Amazon delta region. While expert farmer-fishers are increasingly exposed to shocks and stresses, their ILK plays a key role in mitigating impacts and in strengthening their adaptive responses that are leading to a process of incremental adaptation (PIA). We argue that ILK is the most valuable resource used by expert farmer-fishers to adapt the spatial configuration and composition of their land-/resource-use systems (agrodiversity) and their produced and managed resources (agrobiodiversity) at landscape, community and household levels. We based our findings on ILK on data recorded for over the last 30 years using detailed ethnographic methodologies and multitemporal landscape mapping. We found that the ILK of expert farmer-fishers and their “tradition of change” have facilitated the PIA to intensify a particular production system to optimize production across a broad range of flood conditions and at the same time to manage or conserve forests to produce resources and services.     

Effect of operational parameters on the removal of particulate chemical oxygen demand in the activated sludge process.

The removal of particulate material in the aeration basin of the activated sludge process is mainly attributed to bioflocculation and hydrolysis of particulate substrate. The bioflocculation process in the aeration tank of the activated sludge process occurs only under favorable conditions in the system, and several common operational parameters affect its performance. The principal objective of this research was to observe the effect of mixed liquor suspended solids, solids retention time (SRT), and extracellular polymer substances on the removal of particulate substrate by bioflocculation. A first-order particulate removal expression, based on flocculation, accurately described the removal rates for supernatant suspended solids and colloidal chemical oxygen demand. Based on the results presented in this investigation, a mixed liquor concentration of approximately 2200 mg/L, an SRT of at least 3 days, and a contact time of 30 minutes are needed for relatively complete removal of the particulate substrate in a plug-flow reactor.     

Ontogeny of feeding behavior and cranial morphology in the whitespotted bambooshark <Emphasis Type="Italic">Chiloscyllium plagiosum</Emphasis>

Morphological and behavioral development of the feeding apparatus over early ontogeny can profoundly affect the ability of an organism to obtain nourishment, ultimately impacting survival. The interplay between morphology and behavior over the first year of life was studied in the whitespotted bambooshark Chiloscyllium plagiosum (Bennett 1830) beginning in March of 2002 using high-speed videography and dissection. Externally measured variables describing cranial growth, and jaw weight, scaled at or near isometry while jaw and hyoid musculature, especially the coracohyoideus, demonstrated considerable hypertrophication. The difference between the volume of the buccal cavity when open and closed scaled with substantial positive allometry while the time to reach maximum jaw and hyoid abduction exhibited weak allometry, resulting in the capacity for more rapid and greater volumetric intake during feeding. In addition, the relative forward motion of the predator during a strike decreased over ontogeny and the feeding modality became more suction-dominated. Kinematic variables exhibited little variability and the primary aspect of food capture that was modulated in response to food type was the forward motion of the predator. An increase in capture success was noted for live, elusive shrimp over ontogeny indicating that morphological and behavioral changes have direct consequences for prey acquisition. Conservation of head shape coupled with a narrow behavioral repertoire is hypothesized to increase prey capture success in the wild over ontogeny as individuals become more proficient in the execution of a single, low-variability, suction-dominated capture behavior.     

Modelling Regression and Dispersion Parameters in a Complex Repeated Measures Experiment

We analyze data from a complex repeated measures experiment directed at the evaluation of the response to an electric stimulus applied to mussel nerves under 5 different salinity levels. We discuss the form of the relation between the response and the different salinity levels, as well as the choice of an adequate within subjects covariance structure that includes random effects and autoregressive models.     

Diving of the sea snakePelamis platurus in the Gulf of Panamá

Fifteen yellow-bellied sea snakes,Pelamis platurus, fitted with pressure-sensitive ultrasonic transmitters, were tracked in the Gulf of Panamá during 1983–1985. Snakes spent up to 99.9% ( = 87%) of the tracking time under water and dived to 50 m. The maximum voluntary submergence time observed was 213 min, and of 202 complete dives logged, 19 exceeded 90 min. Dive durations of tracked snakes were typically longer than expected, based upon their estimated body-oxygen stores, and some were even longer than the reported survival times of forceably submerged snakes. Snakes, however, dived repeatedly and did not spend long periods at the surface between dives, suggesting that they did not develop an oxygen deficit during diving. Diving snakes may be able to avoid anaerobiosis by having a reduced metabolic rate, an enhanced rate of cutaneous oxygen uptake, or both. Surface conditions and subsurface temperatures influence the diving behavior ofP. platurus. Laboratory experiments in Panamá indicated that a larger number of snakes were submerged when surface water was turbulent. During February and March, the period of dry season upwelling in the Gulf of Panamá, sea snakes were found to avoid cooler, subsurface water and to make significantly shallower dives: mean maximum depth 6:8 m (n=76) in contrast to a mean maximum depth of 15.1 m (n=147) during the wet season. The dives during the dry season tended to be of shorter duration, with 44% lasting less than 15 min, compared to only 19% of the dives recorded during the wet season being completed in less than 15 min. General avoidance of subsurface temperatures cooler than 19°C was confirmed by laboratory experiments in the 10 m-deep tank at Scripps Institution of Oceanography.     

Leonardo da Vinci’s “Last Supper”: a case study to evaluate the influence of visitors on the Museum preservation systems

Environmental Science and Pollution Research - The most important parameter to obtain an appropriate preservation condition of museum environments concerns the indoor air quality. The exposure of...