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Since the very beginning of astronomy the location of objects on the sky has been a fundamental observational quantity that has been taken for granted. While precise two dimensional positional information is easy to obtain for observations in the electromagnetic spectrum, the positional accuracy of current and near future gravitational wave detectors is limited to between tens and hundreds of square degrees, which makes it extremely challenging to identify the host galaxies of gravitational wave events or to detect any electromagnetic counterparts. Gravitational wave observations provide information on source properties that is complementary to the information in any associated electromagnetic emission. Observing systems with multiple messengers thus has scientific potential much greater than the sum of its parts. A gravitational wave detector with higher angular resolution would significantly increase the prospects for finding the hosts of gravitational wave sources and triggering a multi-messenger follow-up campaign. An observatory with arcminute precision or better could be realised within the Voyage 2050 programme by creating a large baseline interferometer array in space and would have transformative scientific potential. Precise positional information of standard sirens would enable precision measurements of cosmological parameters and offer new insights on structure formation; a high angular resolution gravitational wave observatory would allow the detection of a stochastic background and resolution of the anisotropies within it; it would also allow the study of accretion processes around black holes; and it would have tremendous potential for tests of modified gravity and the discovery of physics beyond the Standard Model. [ABSTRACT FROM AUTHOR]

The World Health Organization (WHO) and the World Organization for Animal Health (OIE) both recognize the importance of veterinary services in controlling zoonotic diseases, in preventing human injury, and in protecting the welfare of non-human animals. Furthermore, both organizations recommend regular evaluations of veterinary programs. Accordingly, we conducted a scoping review to collate the available peer-reviewed evaluations of subsidized small animal veterinary services in terms of the effects on animal and public health. We summarized the evaluation methods used, identified key journals in this disparate literature, and identified gaps in knowledge. CAB Abstracts, PubMed, and Scopus were searched, yielding 1441 records published between 2009 and 2016 for initial screening. After examining titles and keywords, abstracts, and finally full articles, we identified 32 relevant papers that evaluated 27 distinct programs. The global distribution was broad, with half of the papers evaluating programs in Africa or Asia, all of which were rabies vaccination programs targeting dogs. Three program evaluation categories were identified: zoonotic disease prevention (9 papers), animal welfare and control (9 papers), and One Health promotion (14 papers). Nearly three-quarters (72%) of the papers used more than one method for collecting data. The most common data sources were questionnaires (22 papers) and administrative records, such as medical charts (21 papers). The most common indicators used for animal health-related program assessments were the number of animals reached by the program (27 papers) and any changes in animal population demographics (22 papers). These indicators were found in all three types of program evaluations (i.e., zoonotic disease prevention, animal welfare/control, and One Health promotion). For public health-related program assessments, the most common indicators consisted of determining barriers to a veterinary program’s success (13 papers), followed by costs of a program (11 papers), changes in perceived threats or nuisances (11 papers), and community knowledge of a zoonotic disease (11 papers). The small number of papers identified in this review, n = 32, underscores that comprehensive evaluations of subsidized veterinary services are uncommon in the peer-reviewed literature. Yet, when performed, such evaluations can help guide program delivery and future research. Given the high stakes and the high costs of subsidized veterinary services, greater efforts in program evaluation are warranted. [ABSTRACT FROM AUTHOR]

The Laser Interferometer Space Antenna (LISA) has two scientific objectives of cosmological focus: to probe the expansion rate of the universe, and to understand stochastic gravitational-wave backgrounds and their implications for early universe and particle physics, from the MeV to the Planck scale. However, the range of potential cosmological applications of gravitational-wave observations extends well beyond these two objectives. This publication presents a summary of the state of the art in LISA cosmology, theory and methods, and identifies new opportunities to use gravitational-wave observations by LISA to probe the universe. [ABSTRACT FROM AUTHOR]

Iron complexes containing pincer ligands that incorporate N-heterocyclic carbene (NHC) moieties are of significant interest in organometallic catalysis in order to generate more oxidatively robust complexes that may exhibit novel catalytic properties. In order to define the effect that introducing NHC moieties into pincer ligands has on electronic structure and bonding in iron(II)-pincer complexes, MCD and DFT studies of (iPrCDA)FeBr2, (iPrPDI)FeBr2, and (iPrCNC)FeBr2 were performed. These studies quantify the electronic structures and bonding interactions as a function of pincer ligand variation. They also demonstrate that the observed ligand fields (and, hence, spin states) directly correlate to the increased Fe-C bonding and pincer-donating abilities that result from introducing NHC moieties into the pincer ligand. However, the net donor abilities of the pincers and the strength of the Fe-pincer interaction do not directly correlate to the number of NHC moieties present, but instead are determined to be due to differences in Fe-C and overall Fe-pincer bonding as a result of the position of the NHC moieties in the pincer ligand and the overall geometric constraints of the pincer architecture. [ABSTRACT FROM AUTHOR]

More than half a century after the Chapel Hill meeting of 1957, the landscape of general relativity has been transformed. In relativistic cosmology we are entering an era in which we can seriously consider testing some of the most fundamental assumptions that go into our view of the Universe. We propose that precision tests of gravity on cosmological scales may be feasible with up-and-coming surveys of galaxies. To achieve the most accurate general constraints yet we briefly describe a formalism which is applicable on the largest scales: the parametrized post-Friedmann approach. We sketch out the steps that need to be taken to link realistic, cosmological observables with fundamental properties of general relativity. [ABSTRACT FROM AUTHOR]

Access to veterinary services can have positive impacts on animal health and welfare, and on human mental and physical health and well-being; however, many communities worldwide lack access to such services. At their request, the 5 communities of the Sahtu Settlement Area, Northwest Territories, Canada, have received annual access to preventive veterinary services through the University of Calgary's Northern Community Health Rotation since 2008. To determine the reach of the program, we conducted a dog census in 2017. We then conducted a chart review of 11 years of dog medical records from 2008 to 2018 to evaluate how the reach of the program, the uptake of veterinary services, and dog population demographics, health and welfare measures changed over the duration of the program. In the chart review, we used either multi-level logistic regression or generalized linear models, to determine how seven variables, including age, sex, breed, body condition, deworming, vaccination, and sterilization status upon clinic entry, changed over the course of program delivery. Our results suggest that program reach, veterinary service uptake, and dog demographic, health and welfare measures improved over time. We observed high rabies vaccination coverage in some communities (48 %–83 % of the dog population) and moderate overall sterilization status (25 %–56 % of the dog population) with female dog sterilization more common than male (75 % of dogs leaving the 2017 clinics, compared to 43 %). Several dog demographic, health, and welfare measures, including age, body condition, and vaccination, deworming, and sterilization status, were significantly better in later years of the program (all p < 0.001). Differences among communities, both in dog population numbers from the 2017 census (40–89 dogs) and in the uptake of veterinary services in 2017 (48 %–83 % of the dog population), were notable. Vaccination uptake was directly related to clinic attendance, but sterilization was impacted by additional factors, including community members' acceptance of the procedure. Some unintended consequences were noted, however, including the potential effect of sterilization on the availability of traditional dog breeds in the communities. Overall, our study findings demonstrate that subsidized veterinary services provided over a regular and extended period of time benefit animal population demographics, health and welfare, and could have positive impacts on human well-being. The framework of community collaboration and long-term commitment developed through this program serves as a model for achieving common health goals among communities in need and veterinary service providers. [ABSTRACT FROM AUTHOR]

Access to veterinary services in marginalized communities has important implications for people and animals around the world. Subsidized veterinary services are occasionally provided, however, they are seldom evaluated for their value to stakeholders and overall animal health. In 2017, we evaluated a decade-long veterinary program in four remote communities in the Sahtu Settlement Area of the Northwest Territories, Canada to understand if there were changes in dog husbandry and community perceptions of, and experiences with, dogs since an initial assessment at the beginning of the program in 2008. Using questionnaires and a dog census, we found a significant increase over time in dog health indicators, including the proportion of dogs that had received preventive veterinary care and had been sterilized. We documented significant changes in the described purpose of dogs, husbandry practices, experiences with dogs, and attitudes towards dogs and veterinary services. In 2017, respondents commonly described their dog(s) as companions and as part of their family. However, communities differed in the way dogs were housed and fed and in their attitudes towards dogs and dog-related issues. These inter-community differences are noteworthy as they impact service provision, uptake, and evaluation and must be taken into consideration in order to develop effective programs. Regular program evaluations are critical to check in with stakeholders, to ensure the program is meeting community needs, and to optimize effective use of resources. [ABSTRACT FROM AUTHOR]

Homoleptic σ‐bonded uranium–alkyl complexes have been a synthetic target since the Manhattan Project. The current study describes the synthesis and characterization of several unprecedented uranium–methyl complexes. Amongst these complexes, the first example of a homoleptic uranium–alkyl dimer, [Li(THF)4]2[U2(CH3)10], as well as a seven‐coordinate uranium–methyl monomer, {Li(OEt2)Li(OEt2)2UMe7Li}n were both crystallographically identified. The diversity of complexes reported herein provides critical insight into the structural diversity, electronic structure and bonding in uranium–alkyl chemistry. [ABSTRACT FROM AUTHOR]

Homoleptic σ‐bonded uranium–alkyl complexes have been a synthetic target since the Manhattan Project. The current study describes the synthesis and characterization of several unprecedented uranium–methyl complexes. Amongst these complexes, the first example of a homoleptic uranium–alkyl dimer, [Li(THF)4]2[U2(CH3)10], as well as a seven‐coordinate uranium–methyl monomer, {Li(OEt2)Li(OEt2)2UMe7Li}n were both crystallographically identified. The diversity of complexes reported herein provides critical insight into the structural diversity, electronic structure and bonding in uranium–alkyl chemistry. [ABSTRACT FROM AUTHOR]

The combination of simple cobalt salts and N-heterocyclic carbene (NHC) ligands has been highly effective in C–H functionalization, hydroarylation and cross-coupling catalysis, though displaying a strong dependence on the identity of the NHC ligand. In addition, reactions effective with NHC ligands are often ineffective with phosphine ligands, further motivating the evaluation of the fundamental electronic structure and bonding differences in well-defined distorted tetrahedral Co(ii) complexes. Magnetic circular dichroism (MCD) studies indicate that Co(ii)–bisphosphines have larger ligand fields than Co(ii)–NHC complexes. Theoretical density functional theory (DFT) calculations were performed on an expanded set of L2CoCl2 complexes (L2 = NHC, bisphosphine and diamine) to study the electronic structure and relative ligation properties of NHCs compared to bisphosphine and diamine ligands. Mayer bond order and charge decomposition analyses indicate that NHC ligands are slightly stronger donor ligands than bisphosphines but also result in a weakening of Co–Cl bonds in a trans-like influence. From MCD and DFT studies, changing the NHC N-substituent has a larger effect on the ligand field of Co(ii)–NHC complexes than saturating the backbone. Overall, these studies provide detailed insight into the electronic structure and bonding effects in Co(ii) complexes with ligand types commonly explored in catalysis. [ABSTRACT FROM AUTHOR]

Since 2015 the gravitational-wave observations of LIGO and Virgo have transformed our understanding of compact-object binaries. In the years to come, ground-based gravitational-wave observatories such as LIGO, Virgo, and their successors will increase in sensitivity, discovering thousands of stellar-mass binaries. In the 2030s, the space-based LISA will provide gravitational-wave observations of massive black holes binaries. Between the ∼ 10 –103 Hz band of ground-based observatories and the ∼ 1 0 − 4 –10− 1 Hz band of LISA lies the uncharted decihertz gravitational-wave band. We propose a Decihertz Observatory to study this frequency range, and to complement observations made by other detectors. Decihertz observatories are well suited to observation of intermediate-mass (∼ 1 0 2 –104M⊙) black holes; they will be able to detect stellar-mass binaries days to years before they merge, providing early warning of nearby binary neutron star mergers and measurements of the eccentricity of binary black holes, and they will enable new tests of general relativity and the Standard Model of particle physics. Here we summarise how a Decihertz Observatory could provide unique insights into how black holes form and evolve across cosmic time, improve prospects for both multimessenger astronomy and multiband gravitational-wave astronomy, and enable new probes of gravity, particle physics and cosmology. [ABSTRACT FROM AUTHOR]

The gravitational-wave astronomical revolution began in 2015 with LIGO's observation of the coalescence of two stellar-mass black holes. Over the coming decades, ground-based detectors like laser interferometer gravitational-wave observatory (LIGO), Virgo and KAGRA will extend their reach, discovering thousands of stellar-mass binaries. In the 2030s, the space-based laser interferometer space antenna (LISA) will enable gravitational-wave observations of the massive black holes in galactic centres. Between ground-based observatories and LISA lies the unexplored dHz gravitational-wave frequency band. Here, we show the potential of a decihertz observatory (DO) which could cover this band, and complement discoveries made by other gravitational-wave observatories. The dHz range is uniquely suited to observation of intermediate-mass (∼102–104M⊙) black holes, which may form the missing link between stellar-mass and massive black holes, offering an opportunity to measure their properties. DOs will be able to detect stellar-mass binaries days to years before they merge and are observed by ground-based detectors, providing early warning of nearby binary neutron star mergers, and enabling measurements of the eccentricity of binary black holes, providing revealing insights into their formation. Observing dHz gravitational-waves also opens the possibility of testing fundamental physics in a new laboratory, permitting unique tests of general relativity (GR) and the standard model of particle physics. Overall, a DO would answer outstanding questions about how black holes form and evolve across cosmic time, open new avenues for multimessenger astronomy, and advance our understanding of gravitation, particle physics and cosmology. [ABSTRACT FROM AUTHOR]

Abstract: The use of N‐methylpyrrolidone (NMP) as a co‐solvent in ferric salt catalyzed cross‐coupling reactions is crucial for achieving the highly selective, preparative scale formation of cross‐coupled product in reactions utilizing alkyl Grignard reagents. Despite the critical importance of NMP, the molecular level effect of NMP on in situ formed and reactive iron species that enables effective catalysis remains undefined. Herein, we report the isolation and characterization of a novel trimethyliron(II) ferrate species, [Mg(NMP)6][FeMe3]2 (1), which forms as the major iron species in situ in reactions of Fe(acac)3 and MeMgBr under catalytically relevant conditions where NMP is employed as a co‐solvent. Importantly, combined GC analysis and 57Fe Mössbauer spectroscopic studies identified 1 as a highly reactive iron species for the selective formation generating cross‐coupled product. These studies demonstrate that NMP does not directly interact with iron as a ligand in catalysis but, alternatively, interacts with the magnesium cations to preferentially stabilize the formation of 1 over [Fe8Me12]− cluster generation, which occurs in the absence of NMP. [ABSTRACT FROM AUTHOR]

The use of N-methylpyrrolidone (NMP) as a cosolvent in ferric salt catalyzed cross-coupling reactions is crucial for achieving the highly selective, preparative scale formation of cross-coupled product in reactions utilizing alkyl Grignard reagents. Despite the critical importance of NMP, the molecular level effect of NMP on in situ formed and reactive iron species that enables effective catalysis remains undefined. Herein, we report the isolation and characterization of a novel trimethyliron(II) ferrate species, [Mg(NMP)6][FeMe3]2 (1), which forms as the major iron species in situ in reactions of Fe(acac)3 and MeMgBr under catalytically relevant conditions where NMP is employed as a co-solvent. Importantly, combined GC analysis and 57Fe Mössbauer spectroscopic studies identified 1 as a highly reactive iron species for the selective formation generating cross-coupled product. These studies demonstrate that NMP does not directly interact with iron as a ligand in catalysis but, alternatively, interacts with the magnesium cations to preferentially stabilize the formation of 1 over [Fe8Me12]- cluster generation, which occurs in the absence of NMP. [ABSTRACT FROM AUTHOR]

Euclid is a European Space Agency medium-class mission selected for launch in 2019 within the Cosmic Vision 2015 - 2025 program. The main goal of Euclid is to understand the origin of the accelerated expansion of the universe. Euclid will explore the expansion history of the universe and the evolution of cosmic structures by measuring shapes and red-shifts of galaxies as well as the distribution of clusters of galaxies over a large fraction of the sky. Although the main driver for Euclid is the nature of dark energy, Euclid science covers a vast range of topics, from cosmology to galaxy evolution to planetary research. In this review we focus on cosmology and fundamental physics, with a strong emphasis on science beyond the current standard models. We discuss ive broad topics: dark energy and modiied gravity, dark matter, initial conditions, basic assumptions and questions of methodology in the data analysis. This review has been planned and carried out within Euclid's Theory Working Group and is meant to provide a guide to the scientiic themes that will underlie the activity of the group during the preparation of the Euclid mission. [ABSTRACT FROM AUTHOR]

Euclid is a European Space Agency medium-class mission selected for launch in 2020 within the cosmic vision 2015-2025 program. The main goal of Euclid is to understand the origin of the accelerated expansion of the universe. Euclid will explore the expansion history of the universe and the evolution of cosmic structures by measuring shapes and red-shifts of galaxies as well as the distribution of clusters of galaxies over a large fraction of the sky. Although the main driver for Euclid is the nature of dark energy, Euclid science covers a vast range of topics, from cosmology to galaxy evolution to planetary research. In this review we focus on cosmology and fundamental physics, with a strong emphasis on science beyond the current standard models. We discuss five broad topics: dark energy and modified gravity, dark matter, initial conditions, basic assumptions and questions of methodology in the data analysis. This review has been planned and carried out within Euclid’s Theory Working Group and is meant to provide a guide to the scientific themes that will underlie the activity of the group during the preparation of the Euclid mission. [ABSTRACT FROM AUTHOR]