An Isolated Stellar-Mass Black Hole Detected Through Astrometric Microlensing

We report the first unambiguous detection and mass measurement of an isolated stellar-mass black hole (BH). We used the Hubble Space Telescope (HST) to carry out precise astrometry of the source star of the long-duration (t_E ~ 270 days), high-magnification microlensing event MOA-2011-BLG-191/OGLE-2011-BLG-0462, in the direction of the Galactic bulge. HST imaging, conducted at eight epochs over an interval of six years, reveals a clear relativistic astrometric deflection of the background star's apparent position. Ground-based photometry shows a parallactic signature of the effect of the Earth's motion on the microlensing light curve. Combining the HST astrometry with the ground-based light curve and the derived parallax, we obtain a lens mass of 7.1 +/- 1.3 M_Sun and a distance of 1.58 +/- 0.18 kpc. We show that the lens emits no detectable light, which, along with having a mass higher than is possible for a white dwarf or neutron star, confirms its BH nature. Our analysis also provides an absolute proper motion for the BH. The proper motion is offset from the mean motion of Galactic-disk stars at similar distances by an amount corresponding to a transverse space velocity of ~45 km/s, suggesting that the BH received a modest natal 'kick' from its supernova explosion. Previous mass determinations for stellar-mass BHs have come from radial-velocity measurements of Galactic X-ray binaries, and from gravitational radiation emitted by merging BHs in binary systems in external galaxies. Our mass measurement is the first ever for an isolated stellar-mass BH using any technique

Data from: Advancement in long-distance bird migration through individual plasticity in departure

Research summary: Globally, bird migration is occurring earlier, consistent with climate-related changes in breeding resources. Although often attributed to phenotypic plasticity, there is no clear demonstration of long-term population advancement in avian migration through individual plasticity. Using direct observations of bar-tailed godwits (Limosa lapponica) departing New Zealand on a 16,000-km journey to Alaska, we show that migration advanced by six days during 2008–2020, and that within-individual advancement was sufficient to explain this population-level change. However, in individuals tracked for the entire migration, earlier departure did not lead to earlier arrival or breeding in Alaska, due to prolonged stopovers in Asia. Moreover, changes in breeding-site phenology varied across Alaska, but were not reflected in within-population differences in advancement of migratory departure. We demonstrate that plastic responses can drive population-level changes in timing of long-distance migration, but also that behavioral and environmental constraints en route may yet limit adaptive responses to global change. The collection of long-term departure data was supported by Chris & Neville Hopkins, David & Lucile Packard Foundation, Dobberke Foundation for Comparative Psychology, Manawatu Estuary Trust, Marsden Fund (Royal Society of New Zealand), Massey University Doctoral Scholarship, New Zealand Department of Conservation, Ornithological Society of New Zealand, Pacific Shorebird Migration Project, Pūkorokoro Miranda Naturalist’s Trust, and Royal Netherlands Academy of Arts & Sciences

Aspects of writing in 16+ English examinations between 1980 & Vocabulary, spelling, punctuation, sentence structure, non-standard English and their implications for comparability of grading standards

SIGLEGBUnited Kingdo

Asian dance in Britain A selection of researches and reviews

SIGLEAvailable from British Library Document Supply Centre-DSC:98/08559 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Economic imperatives vs environmental quality in the dragon's head The Waigaoqiao Free Trade Zone Shanghai

SIGLEAvailable from British Library Document Supply Centre-DSC:9348.935(56) / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Technopolis emerging? First steps in realising the potential of high-tech development opportunities in the Pudong New Area, Shanghai

SIGLEAvailable from British Library Document Supply Centre-DSC:9348.935(58) / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Leading China into the global economy? Free trade zone developments and opportunities in the Pudong New Area, Shanghai

Available from British Library Document Supply Centre-DSC:9348.935(54) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Community-based grassland management in Western China - Rationale, pilot project experience, and policy implications

Grassland degradation in China is widely perceived to be accelerating, and the. blame is often placed by government officials and researchers on a supposed "tragedy of the commons." Grassland policy seeks to address this through the establishment of household tenure and the derivation and external enforcement of household, stocking rates. Drawing upon the authors' field research at a number of sites in western. China, this article argues that the actual tenure situation is not as open access as is commonly implied and that existing forms of community-based management (including collective and small group tenure) are advantageous, given the socioeconomic and ecological context. Among other things, community-based management can facilitate low-cost external exclusion, economies of size in herd supervision, equal access to pastoral resources, the mitigation of environmental risk, and the prompt resolution of grassland-related disputes, Recent innovative attempts to both improve and formalize collective and group tenure arrangements indicate that there is a wide range of different possible grassland tenure-management models available, in addition to the household tenure-household management model emphasized in grassland policy. China's revised Grassland Law (2003), arguably provides legal space for these alternative models. However, for the future of community-based grassland management to be secure, implementing. agencies need to be more aware of these alternative models and. have the willingness and capacity to adopt a flexible and participatory approach to grassland policy implementation

Multivariate analysis of risk factors for feline hyperthyroidism in New Zealand

AIM: To search for putative risk factors for feline hyperthyroidism in New Zealand, using a case-control study.\ud \ud METHODS: A questionnaire-based case-control study involving the owners of 375 cats in New Zealand (125 hyperthyroid cats, 125 randomly selected control cats, and 125 age- and sex-matched control cats) was conducted to examine associations between potential risk factors and occurrence of feline hyper-thyroidism. Data were collected between December 1996 and February 1998, relative to cat and owner demography and medical history, cats' indoor and outdoor environments, and cats' diets. A range of statistical techniques was employed to analyse the data, including descriptive analyses, univariate logistic regression for each variable and multivariate stepwise forward logistic regression.\ud \ud RESULTS: Multivariate analysis revealed that affected cats were more likely to be female (odds ratio (OR)=3.3; 95% confidence interval (CI)=1.2–9.0) and older than unaffected random control cats. Purebred cats were at a much lower risk of being diagnosed as hyperthyroid than were domestic short- and long-haired cats (OR=0.01; 95% CI=0.001–0.20). If more than one cat was present in a household, hyperthyroidism was less likely to be identified (OR=0.15; 95% CI=0.05–0.44) compared with single-cat households. Hyperthyroid cats were 6.6 times more likely (95% CI=1.8–23.9) to be reported to sleep predominantly on the floor than control cats. Cats whose bedding was regularly treated with anti-flea products appeared to be at a considerably higher risk for hyperthyroidism (OR=57.6; 95% CI=3.8–<200); and, to a lesser extent, so were cats living in households where fly sprays were reported to be used regularly (OR=3.3; 95% CI=1.2–9.3). The interaction between drinking water from puddles and regular use of organic garden fertilisers, such as compost or animal manure, was associated with a 5.3-fold (95% CI=1.1–25.6) increase in the risk of cats being diagnosed with the disease. Hyperthyroid cats were twice as likely (95% CI=0.3–12.9) to have eaten at least half of their daily food requirements as canned commercial cat food compared with unaffected cats. Cats exposed to a variety of flavours of canned cat food were more likely to be diagnosed with hyper-thyroidism than were those fed only one flavour (OR=3.8; 95% CI=1.5–9.6). The presence of dental disorders was associated with a 5.5-fold increase in the risk of being diagnosed as hyper-thyroid and this association was independent of the cat's age (95% CI=1.7–17.5).\ud \ud CONCLUSIONS: The results of this study support and extend those in several earlier reports and show that cats in New Zealand are, in many respects, similar to cats in Europe and North America in terms of their susceptibility to hyperthyroidism. The finding that female cats are predisposed to hyperthyroidism is at variance with most previously published work. It remains unclear which, if any, of the identified disease associations are causal, so further studies of this increasingly prevalent feline endocrinopathy are warranted

Multivariate analysis of risk factors for feline hyperthyroidism in New Zealand

AIM: To search for putative risk factors for feline hyperthyroidism in New Zealand, using a case-control study.\ud \ud METHODS: A questionnaire-based case-control study involving the owners of 375 cats in New Zealand (125 hyperthyroid cats, 125 randomly selected control cats, and 125 age- and sex-matched control cats) was conducted to examine associations between potential risk factors and occurrence of feline hyper-thyroidism. Data were collected between December 1996 and February 1998, relative to cat and owner demography and medical history, cats' indoor and outdoor environments, and cats' diets. A range of statistical techniques was employed to analyse the data, including descriptive analyses, univariate logistic regression for each variable and multivariate stepwise forward logistic regression.\ud \ud RESULTS: Multivariate analysis revealed that affected cats were more likely to be female (odds ratio (OR)=3.3; 95% confidence interval (CI)=1.2–9.0) and older than unaffected random control cats. Purebred cats were at a much lower risk of being diagnosed as hyperthyroid than were domestic short- and long-haired cats (OR=0.01; 95% CI=0.001–0.20). If more than one cat was present in a household, hyperthyroidism was less likely to be identified (OR=0.15; 95% CI=0.05–0.44) compared with single-cat households. Hyperthyroid cats were 6.6 times more likely (95% CI=1.8–23.9) to be reported to sleep predominantly on the floor than control cats. Cats whose bedding was regularly treated with anti-flea products appeared to be at a considerably higher risk for hyperthyroidism (OR=57.6; 95% CI=3.8–<200); and, to a lesser extent, so were cats living in households where fly sprays were reported to be used regularly (OR=3.3; 95% CI=1.2–9.3). The interaction between drinking water from puddles and regular use of organic garden fertilisers, such as compost or animal manure, was associated with a 5.3-fold (95% CI=1.1–25.6) increase in the risk of cats being diagnosed with the disease. Hyperthyroid cats were twice as likely (95% CI=0.3–12.9) to have eaten at least half of their daily food requirements as canned commercial cat food compared with unaffected cats. Cats exposed to a variety of flavours of canned cat food were more likely to be diagnosed with hyper-thyroidism than were those fed only one flavour (OR=3.8; 95% CI=1.5–9.6). The presence of dental disorders was associated with a 5.5-fold increase in the risk of being diagnosed as hyper-thyroid and this association was independent of the cat's age (95% CI=1.7–17.5).\ud \ud CONCLUSIONS: The results of this study support and extend those in several earlier reports and show that cats in New Zealand are, in many respects, similar to cats in Europe and North America in terms of their susceptibility to hyperthyroidism. The finding that female cats are predisposed to hyperthyroidism is at variance with most previously published work. It remains unclear which, if any, of the identified disease associations are causal, so further studies of this increasingly prevalent feline endocrinopathy are warranted