107 research outputs found
Portfolio preferences of foreign institutional investors
The authors examine the relationship between foreign investment and the attributes of emerging market countries and firms in which investment is made. Their findings indicate that countries with higher levels of economic development and floating exchange rate regimes tend to have greater ability to obtain foreign capital. After controlling for the country's level of economic development, they find that firms in countries with stronger shareholder rights and legal framework attract more foreign capital. The authors also find that foreign institutions allocate more of their assets to firms with better corporate governance after controlling for other country and firm attributes. The main firm-level measures of corporate governance are derived from accounting quality variables. Their results imply that steps can be taken both at the country and the firm level to create an environment conducive to foreign portfolio investment. The analysis is based on a unique dataset consisting of equity positions of U.S. mutual funds in emerging markets.Payment Systems&Infrastructure,Economic Theory&Research,Labor Policies,International Terrorism&Counterterrorism,Financial Intermediation,International Terrorism&Counterterrorism,Economic Theory&Research,Financial Intermediation,Environmental Economics&Policies,Banks&Banking Reform
Imaging and Control of Surface Magnetization Domains in a Magnetoelectric Antiferromagnet
Common Sole Larvae Survive High Levels of Pile-Driving Sound in Controlled Exposure Experiments
In view of the rapid extension of offshore wind farms, there is an urgent need to improve our knowledge on possible adverse effects of underwater sound generated by pile-driving. Mortality and injuries have been observed in fish exposed to loud impulse sounds, but knowledge on the sound levels at which (sub-)lethal effects occur is limited for juvenile and adult fish, and virtually non-existent for fish eggs and larvae. A device was developed in which fish larvae can be exposed to underwater sound. It consists of a rigid-walled cylindrical chamber driven by an electro-dynamical sound projector. Samples of up to 100 larvae can be exposed simultaneously to a homogeneously distributed sound pressure and particle velocity field. Recorded pile-driving sounds could be reproduced accurately in the frequency range between 50 and 1000 Hz, at zero to peak pressure levels up to 210 dB re 1µPa2 (zero to peak pressures up to 32 kPa) and single pulse sound exposure levels up to 186 dB re 1µPa2s. The device was used to examine lethal effects of sound exposure in common sole (Solea solea) larvae. Different developmental stages were exposed to various levels and durations of pile-driving sound. The highest cumulative sound exposure level applied was 206 dB re 1µPa2s, which corresponds to 100 strikes at a distance of 100 m from a typical North Sea pile-driving site. The results showed no statistically significant differences in mortality between exposure and control groups at sound exposure levels which were well above the US interim criteria for non-auditory tissue damage in fish. Although our findings cannot be extrapolated to fish larvae in general, as interspecific differences in vulnerability to sound exposure may occur, they do indicate that previous assumptions and criteria may need to be revised
Using a Delphi process to determine optimal care for patients with pancreatic cancer
Aim
Overall 5-year survival for pancreatic cancer is ~5%. Optimising the care that pancreatic cancer patients receive may be one way of improving outcomes. The objective of this study was to establish components of care which Australian health professionals believe important to optimally manage patients with pancreatic cancer.
Methods
Using a Delphi process, a multi-disciplinary panel of 250 health professionals were invited to provide a list of factors they considered important for optimal care of pancreatic cancer patients. They were then asked to score and then rescore (from one (no importance/disagree) to 10 (very important/agree) the factors. The mean and coefficient of variation scores were calculated and categorised into three levels of importance.
Results
Overall 63 (66% of those sent the final questionnaire; 25% of those initially invited) health professionals from 9 disciplines completed the final scoring of 55 statements/factors encompassing themes of presentation/staging, surgery and biliary obstruction, multi-disciplinary team details and oncology. Mean scores ranged from 3.7 to 9.7 with the highest related to communication and patient assessment. There was substantial intra- and inter- disciplinary variation in views about MDT membership and roles.
Conclusion
Overall the opinions of Australian health professionals reflect international guideline recommended care; however they identified a number of additional factors focusing on where patients should be treated, the importance of clear communication and the need for multi-disciplinary care which were not included in current clinical practice guidelines. Differences in priorities between specialty groups were also identified
Of volatiles and peptides: in search for MHC-dependent olfactory signals in social communication
The effect of climate change on avian offspring production: A global meta-analysis
Climate change affects timing of reproduction in many bird species, but few studies have investigated its influence on annual reproductive output. Here, we assess changes in the annual production of young by female breeders in 201 populations of 104 bird species (N = 745,962 clutches) covering all continents between 1970 and 2019. Overall, average offspring production has declined in recent decades, but considerable differences were found among species and populations. A total of 56.7% of populations showed a declining trend in offspring production (significant in 17.4%), whereas 43.3% exhibited an increase (significant in 10.4%). The results show that climatic changes affect offspring production through compounded effects on ecological and life history traits of species. Migratory and larger-bodied species experienced reduced offspring production with increasing temperatures during the chick-rearing period, whereas smaller-bodied, sedentary species tended to produce more offspring. Likewise, multi-brooded species showed increased breeding success with increasing temperatures, whereas rising temperatures were unrelated to repro- ductive success in single-brooded species. Our study suggests that rapid declines in size of bird populations reported by many studies from different parts of the world are driven only to a small degree by changes in the production of young
Collaborative Synthesis for Neglected Diseases through the Open Synthesis Network: Structure–Activity Relationships of Arylaminopyrazoles as Chagas Disease Treatments
Neglected tropical diseases (NTDs) make up a diverse group of debilitating illnesses disproportionately affecting impoverished communities in tropical and subtropical regions. Despite their significant global health burden, they are often overshadowed by more prominent diseases, resulting in a critical lack of investment in the research and development of new treatments. A renewed focus on NTDs is, therefore, urgently needed, particularly in terms of novel therapeutic strategies. The Open Synthesis Network, launched by DNDi and partner institutions in 2016, is an innovation powerhouse that taps into the potential of students to help drive the discovery of new drugs for patients living with NTDs. We present the results of student-led work into the development of a series of aminopyrazoles for Chagas disease, a multisystemic disease caused by the Trypanosoma cruzi parasite. Seventy-four compounds were synthesized by undergraduate and postgraduate students from six universities from Brazil, Ghana, Germany, USA, and UK, illustrating that open innovation and collaboration for education can drive drug discovery forward. Early evaluation of the structure−activity relationships identified a range of potent hit compounds with selectivity for T. cruzi and no observable cytotoxicity. continued..
Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network
Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects
Ultralight vector dark matter search using data from the KAGRA O3GK run
Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM
Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo
Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level
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