Sperm number and velocity affect sperm competition success in the guppy (Poecilia reticulata)

While both sperm number and quality are now recognized to be important in determining the outcome of sperm competition, very few studies have experimentally assessed the influence of these two parameters simultaneously. We studied the effect of sperm quality and number on competitive fertilization success in an internal-fertilizing fish, the guppy (Poecilia reticulata), which is characterized by high levels of sperm competition. We artificially inseminated virgin females with varying proportion of sperm from two competing males, while holding constant the total number of sperm transferred to the female. Sperm morphology and sperm swimming velocity were also determined prior to insemination. The paternity outcome of sperm competition trials was assessed through molecular analyses of the resulting offspring using polymorphic microsatellite loci. We found that both sperm number and sperm velocity affected the outcome of sperm competition, with males that contributed more and faster sperm achieving a greater paternity share.     

Behavioural interference between ungulate species: roe are not on velvet with fallow deer

Interference is expected to occur at feeding areas between species with a similar diet, but few studies have tested this idea for wild ungulates. We analysed interactions between fallow deer, European roe deer and wild boar, in three sites, in a Mediterranean area. We expected that interference should be greater between deer than between them and wild boar. We documented the negative effects of behavioural interference by fallow on foraging behaviour of roe deer, under field conditions. Deer species built up 90% interference interactions, with fallow always dominant on roe, also through direct aggression. Although roe deer decreased feeding and increased vigilance levels in proximity (<50 m) of either fallow deer or wild boar, they were displaced significantly more often by the former than by the latter. Fallow deer were neither displaced nor alarmed by roe and rarely by wild boar. No deer species displaced wild boar. Interference was significantly greater on solitary roe deer, especially females, in spring and roe left the feeding ground most often in the smallest site (13 ha). Roe deer avoided areas where the local density of fallow deer was the highest. During our 4-year-study, roe deer density decreased whereas fallow deer numbers increased. Behavioural interference may explain how fallow deer outcompete roe deer through spatial exclusion from feeding sites and avoidance of areas with high densities of the former. Fallow deer evolved in semi-arid, relatively poor habitats of Asia Minor: interspecific defence of crucial resources could have developed as a beneficial tactic for its survival.     

Detection of Enteroviruses in Influent and Effluent Flow Samples from Wastewater Treatment Plants in Italy

This study evaluated the presence and seasonal distribution of polio and other enteroviruses in four wastewater treatment plants in three cities in Italy, using different treatment systems. Detection of enteroviruses was carried out by virus isolation in cell cultures after concentration of water samples collected at both inlet and outlet of the treatment plants, following the methods described in the WHO guidelines. Viral serotypes isolated before and after water treatment were compared. Forty-eight non-polio enteroviruses were isolated from 312 samples collected at the inlet of the four wastewater treatment plants, 35 of which were Coxsackievirus type B (72.9 %) and 13 Echovirus (27.1 %). After treatment, 2 CVB3, 1 CVB5, and 1 Echo 6 were isolated. CVB3 and Echo 6 serotypes were also detected in samples collected at the inlet of the TP, in the same month and year. The high rate of detection of infectious enteroviruses in inlet sewage samples (30.1 %) indicates wide diffusion of these viruses in the populations linked to the collectors. The incomplete removal of infectious viruses following sewage treatment highlights possible risks for public health relate to treated waters discharge into the environment.     

Identification and Genotyping of Human Sapoviruses Collected from Sewage Water in Naples and Palermo, Italy, in 2011

Human sapoviruses were identified in 15 (12.4 %) of 121 inlet sewage samples collected from wastewater treatment plants in Naples and Palermo, Italy, in 2011. All strains, except one GI.1, were genotyped as GI.2 by sequencing a capsid gene fragment. This is the first detection of sapovirus in wastewaters in Italy.     

Isolation of single circulating trophoblasts from maternal circulation for noninvasive fetal copy number variant profiling

Objective

To develop a multi-step workflow for the isolation of circulating extravillous trophoblasts (cEVTs) by describing the key steps enabling a semi-automated process, including a proprietary algorithm for fetal cell origin genetic confirmation and copy number variant (CNV) detection.

Methods

Determination of the limit of detection (LoD) for submicroscopic CNV was performed by serial experiments with genomic DNA and single cells from Coriell cell line biobank with known imbalances of different sizes. A pregnancy population of 372 women was prospectively enrolled and blindly analyzed to evaluate the current workflow.

Results

An LoD of 800 Kb was demonstrated with Coriell cell lines. This level of resolution was confirmed in the clinical cohort with the identification of a pathogenic CNV of 800 Kb, also detected by chromosomal microarray. The mean number of recovered cEVTs was 3.5 cells per sample with a significant reverse linear trend between gestational age and cEVT recovery rate and number of recovered cEVTs. In twin pregnanices, evaluation of zygosity, fetal sex and copy number profiling was performed in each individual cell.

Conclusion

Our semi-automated methodology for the isolation and single-cell analysis of cEVTS supports the feasibility of a cell-based noninvasive prenatal test for fetal genomic profiling.     

The Role of Residual Contaminants and Recycling Steps on Rheological Properties of Recycled Polypropylene

Journal of Polymers and the Environment - Recycling of polymers is one of the alternatives to reduce the impact of polymers presence on the environmental. However, the contaminants, defined as...     

Development of a hybrid photo-bioreactor and nanoparticle adsorbent system for the removal of CO2 , and selected organic and metal co-pollutants

Fossil fuel combustion and many industrial processes generate gaseous emissions that contain a number of toxic organic pollutants and carbon dioxide (CO₂) which contribute to climate change and atmospheric pollution. There is a need for green and sustainable solutions to remove air pollutants, as opposed to conventional techniques which can be expensive, consume additional energy and generate further waste. We developed a novel integrated bioreactor combined with recyclable iron oxide nano/micro-particle adsorption interfaces, to remove CO_2, and undesired organic air pollutants using natural particles, while generating oxygen. This semi-continuous bench-scale photo-bioreactor was shown to successfully clean up simulated emission streams of up to 45% CO₂ with a conversion rate of approximately 4% CO₂ per hour, generating a steady supply of oxygen (6 mmol/hr), while nanoparticles effectively remove several undesired organic by-products. We also showed algal waste of the bioreactor can be used for mercury remediation. We estimated the potential CO₂ emissions that could be captured from our new method for three industrial cases in which, coal, oil and natural gas were used. With a 30% carbon capture system, the reduction of CO₂ was estimated to decrease by about 420,000, 320,000 and 240,000 metric tonnes, respectively for a typical 500 MW power plant. The cost analysis we conducted showed potential to scale-up, and the entire system is recyclable and sustainable. We further discuss the implications of usage of this complete system, or as individual units, that could provide a hybrid option to existing industrial setups.     

Changes in Environmental Conditions Modify Infection Kinetics of Dairy Phages

Latent period, burst time, and burst size, kinetic parameters of phage infection characteristic of a given phage/host system, have been measured for a wide variety of lactic acid bacteria. However, most studies to date were conducted in optimal growth conditions of host bacteria and did not consider variations due to changes in external factors. In this work, we determined the effect of temperature, pH, and starvation on kinetic parameters of phages infecting Lactobacillus paracasei, Lactobacillus plantarum, and Leuconostoc mesenteroides. For kinetics assessment, one-step growth curves were carried out in MRS broth at optimal conditions (control), lower temperature, pH 6.0 and 5.0 (MRS₆ and MRS₅, respectively), or in medium lacking carbon (MRS_N) or nitrogen (MRS_C) sources. Phage infection was progressively impaired as environmental conditions were modified from optimal. At lower temperature or pH, infection was delayed, as perceived by longer latent and burst times. Burst size, however, was lower, equal or higher than for controls, but this effect was highly dependent on the particular phage–host system studied. Phage infection was strongly inhibited in MRS_C, but only mildly impaired in MRS_N. Nevertheless, growth of all the bacterial strains tested was severely compromised by starvation, without significant differences between MRS_C and MRS_N, indicating that nitrogen compounds are specifically required for a successful phage infection, beyond their influence on bacterial growth.     

Prevalence and drivers of poison use by South African commercial farmers and perceptions of alternative livestock protection measures

The use of poison to eliminate predators is causing African vulture populations to collapse. To understand the prevalence and motivations of this practice we conducted an extensive survey with South African commercial farmers. Using a specialised questioning technique and ad hoc quantitative methods we found that an estimated 22% and 31% of farmers used poison over a 1-year and 5-year period, respectively. Poison use hotspots generally coincided with small stock farming areas. The strongest predictor of poison use was whether farmers believed the practice to be common amongst their peers. Our results suggest that farmers’ attitudes to vultures are primarily positive, and farmers are less likely to use poisons if they frequently encounter vultures on their farm. Overall, our findings provide an understanding on poison use that provides leverage points to change farmers’ behaviour and help avert the African vulture crisis and possible cascading ecosystem impacts.Supplementary informationThe online version of this article (10.1007/s13280-020-01461-2) contains supplementary material, which is available to authorized users.     

Autotrophic nitrogen removal for decentralized treatment of ammonia-rich industrial textile wastewater: process assessment,stabilization and modelling

Environmental Science and Pollution Research - Digital textile printing (DTP) is a game-changer technology that is rapidly expanding worldwide. On the other hand, process wastewater is rich in...