Sustainable intensification? Increased production diminishes omega-3 content of sheep milk

Intensifying agricultural production alters food composition, but this is often ignored when assessing system sustainability, yet it could compromise consumers’ health and the concept of ‘sustainable diets’. Here we consider milk composition from Mediterranean dairy sheep, finding inferior fatty acid (FA) profiles with respect to consumer health as a result of a more intensive system of production. Semi-intensive management did produce 57% more milk per ewe with 20% lower fat content, but inferior fat composition. Milk had a nutritionally poorer fatty acid (FA) profile, with 18% less omega-3 FA (n-3) (19% less long-chain n-3) and 7% less monounsaturated FA but 3% more saturated FA (9% higher in C14:0) concentrations compared with ewes under traditional, extensive management. Redundancy analysis identified close associations between fat composition and animal diets, particularly concentrate supplementation and grazing cultivated pasture - n-3 was associated with grazing diverse, native mountain pastures. The paper questions if identifying such key elements in traditional systems could be deployed for ‘sustainable intensification’ to maintain food quality whilst increasing output

Optimized consumer-centric demand response

Demand side management has focused more on centralized control and heavily depends on continuous consumer interaction, often overlooking consumer thermal and visual comfort. Distribution grid management will necessitate the active involvement of new market actors (i.e. prosumers, aggregators, distribution system operators, retailers, etc.), so a holistic approach becomes critical to transform demand into an active element of electricity system management. This paper presents a consumer centric demand flexibility framework, which facilitates the automated, human-centric demand response, minimizes consumer interactions and accommodates various power system ancillary services

Effect of intensification practices, lambing period and environmental parameters on animal health, and milk yield and quality in dairy sheep production systems on Crete

Due to increasing demand, many traditional, grazing-based Mediterranean sheep production systems have introduced intensified feeding regimes, increased investments in facilities and equipment (milking machines) and modified their veterinary regimes to increase milk yields. However, compared to bovine milk production systems, there is limited knowledge about the impact of these intensification practices on animal welfare/health and on the quality of dairy products. The aim of this study was therefore to quantify the effects of production intensity/feeding regimes, lambing period and environmental background conditions on udder health parameters, gastrointestinal nematode infection levels and milk yield and quality parameters in traditional Sfakiano sheep production systems in Crete. Milk yields were higher in semi-intensive production systems while concentrations of several nutritionally desirable compounds such as omega-3 fatty acids were found to be higher in milk from extensive systems. Antibiotic and anthelmintic use was relatively low in both extensive and semi-intensive production systems there was no substantial difference in faecal egg counts, somatic cell counts (a marker for subclinical mastitis) and mi-cro-biological parameters assessed in milk. Recording of flock health parameters showed that animal health/welfare was high in both extensive and semi-intensively managed flocks, and that overall, the health status of extensively managed ewes was slightly better. In contrast, environ-mental conditions (temperature and rainfall) had a substantial effect on nematode infection levels and milk quality parameters assessed

SN2019wxt: An ultrastripped supernova candidate discovered in the electromagnetic follow-up of a gravitational wave trigger

We present optical, radio, and X-ray observations of a rapidly evolving transient SN2019wxt (PS19hgw), discovered during the search for an electromagnetic counterpart to the gravitational-wave (GW) trigger S191213g. Although S191213g was not confirmed as a significant GW event in the off-line analysis of LIGO-Virgo data, SN2019wxt remained an interesting transient due to its peculiar nature. The optical/near-infrared (NIR) light curve of SN2019wxt displayed a double-peaked structure evolving rapidly in a manner analogous to currently known ultrastripped supernovae (USSNe) candidates. This double-peaked structure suggests the presence of an extended envelope around the progenitor, best modeled with two components: (i) early-time shock-cooling emission and (ii) late-time radioactive 56Ni decay. We constrain the ejecta mass of SN2019wxt at Mej ≈ 0.20M⊙, which indicates a significantly stripped progenitor that was possibly in a binary system. We also followed up SN2019wxt with long-term Chandra and Jansky Very Large Array observations spanning ∼260 days. We detected no definitive counterparts at the location of SN2019wxt in these long-term X-ray and radio observational campaigns. We establish the X-ray upper limit at 9.93 × 10−17 erg cm−2 s−1 and detect an excess radio emission from the region of SN2019wxt. However, there is little evidence for SN1993J- or GW170817-like variability of the radio flux over the course of our observations. A substantial host-galaxy contribution to the measured radio flux is likely. The discovery and early-time peak capture of SN2019wxt in optical/NIR observations during EMGW follow-up observations highlight the need for dedicated early, multiband photometric observations to identify USSNe

Constraining the Kilonova Rate with Zwicky Transient Facility Searches Independent of Gravitational Wave and Short Gamma-ray Burst Triggers

The first binary neutron star merger, GW170817, was accompanied by a radioactivity-powered optical/infrared transient called a kilonova. To date, no compelling kilonova has been found during optical surveys of the sky, independent of gravitational-wave triggers. In this work, we searched the first 23 months of the Zwicky Transient Facility (ZTF) data stream for candidate kilonovae in the form of rapidly evolving transients. We combined ZTF alert queries with forced point-spread-function photometry and nightly flux stacking to increase our sensitivity to faint and fast transients. Automatic queries yielded $>11,200$ candidates, 24 of which passed quality checks and strict selection criteria based on a grid of kilonova models tailored for both binary neutron star and neutron star-black hole mergers. None of the candidates in our sample was deemed a possible kilonova after thorough vetting, catalog cross-matching, and study of their color evolution. The sources that passed our selection criteria are dominated by Galactic cataclysmic variables. In addition, we identified two fast transients at high Galactic latitude, one of which is the confirmed afterglow of long-duration GRB190106A, and the other is a possible cosmological afterglow. Using a survey simulation code, we constrained the kilonova rate for a range of models including top-hat and linearly decaying light curves and synthetic light curves obtained with radiative transfer simulations. For prototypical GW170817-like kilonovae, we constrain the rate to be $R < 1775$ Gpc$^{-3}$ yr$^{-1}$ at 95% confidence level by requiring at least 2 high-significance detections. By assuming a population of kilonovae with the same geometry and composition of GW170817 observed under a uniform viewing angle distribution, we obtained a constraint on the rate of $R < 4029$ Gpc$^{-3}$ yr$^{-1}$.Comment: Submitted for publication in Ap

Constraining the Kilonova Rate with Zwicky Transient Facility Searches Independent of Gravitational Wave and Short Gamma-Ray Burst Triggers

The first binary neutron star merger, GW170817, was accompanied by a radioactivity-powered optical/infrared transient called a kilonova. To date, no compelling kilonova has been found in all-sky optical surveys, independently of short gamma-ray burst and gravitational-wave triggers. In this work, we searched the first 23 months of the Zwicky Transient Facility (ZTF) data stream for candidate kilonovae in the form of rapidly evolving transients. We combined ZTF alert queries with forced point-spread-function photometry and nightly flux stacking to increase our sensitivity to faint and fast transients. Automatic queries yielded >11,200 candidates, 24 of which passed quality checks and selection criteria based on a grid of kilonova models tailored for both binary neutron star and neutron star–black hole mergers. None of the candidates in our sample was deemed a possible kilonova after thorough vetting. The sources that passed our selection criteria are dominated by Galactic cataclysmic variables. We identified two fast transients at high Galactic latitude, one of which is the confirmed afterglow of long-duration GRB 190106A, the other is a possible cosmological afterglow. Using a survey simulation code, we constrained the kilonova rate for a range of models including top-hat, linearly decaying light curves, and synthetic light curves obtained with radiative transfer simulations. For prototypical GW170817-like kilonovae, we constrain the rate to be R < 1775 Gpc⁻³ yr⁻¹ (95% confidence). By assuming a population of kilonovae with the same geometry and composition of GW170817 observed under a uniform viewing angle distribution, we obtained a constraint on the rate of R < 4029 Gpc⁻³ yr⁻¹

Constraining the Kilonova Rate with Zwicky Transient Facility Searches Independent of Gravitational Wave and Short Gamma-Ray Burst Triggers

The first binary neutron star merger, GW170817, was accompanied by a radioactivity-powered optical/infrared transient called a kilonova. To date, no compelling kilonova has been found in all-sky optical surveys, independently of short gamma-ray burst and gravitational-wave triggers. In this work, we searched the first 23 months of the Zwicky Transient Facility (ZTF) data stream for candidate kilonovae in the form of rapidly evolving transients. We combined ZTF alert queries with forced point-spread-function photometry and nightly flux stacking to increase our sensitivity to faint and fast transients. Automatic queries yielded &gt;11,200 candidates, 24 of which passed quality checks and selection criteria based on a grid of kilonova models tailored for both binary neutron star and neutron star-black hole mergers. None of the candidates in our sample was deemed a possible kilonova after thorough vetting. The sources that passed our selection criteria are dominated by Galactic cataclysmic variables. We identified two fast transients at high Galactic latitude, one of which is the confirmed afterglow of long-duration GRB 190106A, the other is a possible cosmological afterglow. Using a survey simulation code, we constrained the kilonova rate for a range of models including top-hat, linearly decaying light curves, and synthetic light curves obtained with radiative transfer simulations. For prototypical GW170817-like kilonovae, we constrain the rate to be Gpc-3 yr-1 (95% confidence). By assuming a population of kilonovae with the same geometry and composition of GW170817 observed under a uniform viewing angle distribution, we obtained a constraint on the rate of R &lt; 4029 Gpc-3 yr-1. © 2020. The American Astronomical Society