446 research outputs found
'Let's make lots of money': the determinants of performance in the recorded music sector
This research analyzes the performance of 467 record labels in eight European countries over a period of 13 years (2003-2015). The main goal is to explain a relative measure of profitability in terms of observed variables, although the nature of the dataset also allows us to include non-observed firm and country effects. To this end alternative models are estimated and three main research questions are tested, namely: (1) the effect of the dual structure of the recorded music market, in which a competitive segment and an oligopoly coexist; (2) the extent and source of the volatility of profits in record labels; and (3) the nonlinear impact of size on performance
Finding turning-points in ultra-high-resolution animal movement data
1. Recent advances in biologging have resulted in animal location data at unprecedentedly high temporal resolutions, sometimes many times per second. However, many current methods for analysing animal movement (e.g. step selection analysis or state-space modelling) were developed with lower-resolution data in mind. To make such methods usable with high-resolution data, we require techniques to identify features within the trajectory where movement deviates from a straight line.
2. We propose that the intricacies of movement paths, and particularly turns, reflect decisions made by animals so that turn points are particularly relevant for behavioural ecologists. As such, we introduce a fast, accurate algorithm for inferring turning-points in high-resolution data. For analysing big data, speed and scalability are vitally important. We test our algorithm on simulated data, where varying amounts of noise were added to paths of straight-line segments interspersed with turns. We also demonstrate our algorithm on data of free-ranging oryx (Oryx leucoryx). We compare our algorithm to existing statistical techniques for break-point inference.
3. The algorithm scales linearly and can analyse several hundred-thousand data-points in a few seconds on a mid-range desktop computer. It identified turnpoints in simulated data with complete accuracy when the noise in the headings had a standard deviation of 8 degrees, well within the tolerance of many modern biologgers. It has comparable accuracy to the existing algorithms tested, and is up to three orders of magnitude faster.
4. Our algorithm, freely available in R and Python, serves as an initial step in processing ultra high-resolution animal movement data, resulting in a rarefied path that can be used as an input into many existing step-and-turn methods of analysis. The resulting path consists of points where the animal makes a clear turn, and thereby provides valuable data on decisions underlying movement patterns. As such, it provides an important breakthrough required as a starting point for analysing sub-second resolution data
Transrectal drainage of a diverticular abscess using a pigtail catheter without radiological guidance: a case report
<p>Abstract</p> <p>Introduction</p> <p>Percutaneous or endocavitory drainage of a diverticular abscess under radiological guidance often enables one to perform a one-staged resection and anastomosis (without stoma formation) instead of a two-staged procedure. It reduces the significant postoperative morbidity and mortality associated with the conventional emergency surgical management. However, radiological guidance is not always available due to limited resources during out-of-hours.</p> <p>Case presentation</p> <p>A 78-year-old Caucasian woman underwent transrectal drainage of a diverticular abscess performed with a pigtail catheter without radiological guidance. Technical details of the procedure are described and alternative options discussed.</p> <p>Conclusion</p> <p>In carefully selected patients, per-rectal drainage using a pigtail catheter can be performed without radiological guidance and the procedure offers a simple and effective way of controlling sepsis.</p
Financial crises and the attainment of the SDGs: an adjusted multidimensional poverty approach
This paper analyses the impact of financial crises on the Sustainable Development Goal of eradicating poverty. To do so, we develop an adjusted Multidimensional Poverty Framework (MPF) that includes 15 indicators that span across key poverty aspects related to income, basic needs, health, education and the environment. We then use an econometric model that allows us to examine the impact of financial crises on these indicators in 150 countries over the period 1980–2015. Our analysis produces new estimates on the impact of financial crises on poverty’s multiple social, economic and environmental aspects and equally important captures dynamic linkages between these aspects. Thus, we offer a better understanding of the potential impact of current debt dynamics on Multidimensional Poverty and demonstrate the need to move beyond the boundaries of SDG1, if we are to meet the target of eradicating poverty. Our results indicate that the current financial distress experienced by many low-income countries may reverse the progress that has been made hitherto in reducing poverty. We find that financial crises are associated with an approximately 10% increase of extreme poor in low-income countries. The impact is even stronger in some other poverty aspects. For instance, crises are associated with an average decrease of government spending in education by 17.72% in low-income countries. The dynamic linkages between most of the Multidimensional Poverty indicators, warn of a negative domino effect on a number of SDGs related to poverty, if there is a financial crisis shock. To pre-empt such a domino effect, the specific SDG target 17.4 on attaining long-term debt sustainability through coordinated policies plays a key role and requires urgent attention by the international community
Overlapping Ablation Using a Coaxial Radiofrequency Electrode and Multiple Cannulae System: Experimental Study in ex-Vivo Bovine Liver
Objective To assess the sizes and configurations of thermal zones after overlapping ablations using a coaxial radiofrequency (RF) electrode and multiple cannulae in ex-vivo bovine liver. Materials and Methods For ablation procedures, a coaxial RF electrode and introducer set was used. Employing real-time ultrasound guidance and overlapping techniques in explanted, fresh bovine liver, we created five kinds of thermal zones with one (n=10), two (n=8), four (n=3), and six ablation spheres (n=3). Following ablation, MR images were obtained and the dimensions of all thermal zones were measured on the longitudinal or transverse section of specimens. The shape of the composite ablation zones was evaluated using three-dimensional MR image reconstruction. Results At gross pathologic examination of ten single-ablation zones (spheres), the long-axis (transverse) and short-axis lengths of zones ranged from 3.7 to 4.4 (mean, 4.1) cm and from 3.5 to 4.0 (mean, 3.7) cm, respectively. The long-axis (transverse) and short-axis lengths of double-ablation zones (cylinders) with 23% overlap ranged from 7.0 to 7.7 (mean, 7.3) cm and from 3.0 to 3.9 (mean, 3.5) cm, respectively; those with 58% overlap ranged from 6.0 to 6.4 (mean, 6.2) cm and from 3.8 to 4.6 (mean, 4.3) cm, respectively. The long-axis (diagonal) and short-axis lengths on a transverse section of four-ablation zones (cakes) ranged from 8.5 to 9.7 (mean, 9.1) cm and from 3.0 to 4.1 (mean, 3.7) cm, respectively. Gross pathologic examination of three composite six-ablation zones (spheres) showed that the long-axis (diagonal) and short-axis lengths of zones ranged from 9.0 to 9.9 (mean, 9.4) cm and from 6.8 to 7.5 (mean, 7.2) cm, respectively. T2-weighted MR images depicted low-signal thermal zones containing multiple curvilinear and spotty regions of hyperintensity. Conclusion Using a coaxial RF electrode and multiple cannulae, together with ultrasound guidance and precise overlapping ablation techniques, we successfully created predictable thermal zones in ex-vivo bovine liver.ope
Genome of a middle Holocene hunter-gatherer from Wallacea
Much remains unknown about the population history of early modern humans in southeast Asia, where the archaeological record is sparse and the tropical climate is inimical to the preservation of ancient human DNA1. So far, only two low-coverage pre-Neolithic human genomes have been sequenced from this region. Both are from mainland Hòabìnhian hunter-gatherer sites: Pha Faen in Laos, dated to 7939–7751 calibrated years before present (yr cal bp; present taken as ad 1950), and Gua Cha in Malaysia (4.4–4.2 kyr cal bp)1. Here we report, to our knowledge, the first ancient human genome from Wallacea, the oceanic island zone between the Sunda Shelf (comprising mainland southeast Asia and the continental islands of western Indonesia) and Pleistocene Sahul (Australia–New Guinea). We extracted DNA from the petrous bone of a young female hunter-gatherer buried 7.3–7.2 kyr cal bp at the limestone cave of Leang Panninge2 in South Sulawesi, Indonesia. Genetic analyses show that this pre-Neolithic forager, who is associated with the ‘Toalean’ technocomplex3,4, shares most genetic drift and morphological similarities with present-day Papuan and Indigenous Australian groups, yet represents a previously unknown divergent human lineage that branched off around the time of the split between these populations approximately 37,000 years ago5. We also describe Denisovan and deep Asian-related ancestries in the Leang Panninge genome, and infer their large-scale displacement from the region today.The Toalean burial from Leang Panninge Genomic analysis Discussio
Solutions of the heat conduction equation in multilayers for photothermal deflection experiments
Optical properties of MgH2 measured in situ in a novel gas cell for ellipsometry/spectrophotometry
The dielectric properties of alpha-MgH2 are investigated in the photon energy
range between 1 and 6.5 eV. For this purpose, a novel sample configuration and
experimental setup are developed that allow both optical transmission and
ellipsometric measurements of a transparent thin film in equilibrium with
hydrogen. We show that alpha-MgH2 is a transparent, colour neutral insulator
with a band gap of 5.6 +/- 0.1 eV. It has an intrinsic transparency of about
80% over the whole visible spectrum. The dielectric function found in this work
confirms very recent band structure calculations using the GW approximation by
Alford and Chou [J.A. Alford and M.Y. Chou (unpublished)]. As Pd is used as a
cap layer we report also the optical properties of PdHx thin films.Comment: REVTeX4, 15 pages, 12 figures, 5 table
The performance effects of creative imitation on original products: Evidence from lab and field experiments
Research Summary: A market entrant often challenges the incumbent using creative imitation: The entrant creatively combines imitated aspects of the original with its own innovative characteristics to create a distinct offering. Using lab and field experiments to examine creative imitation in China, we find the effects of creative imitations on the originals depend on the creative imitation's quality. We explore the underlying mechanisms, and show that including a low-quality creative imitation in the retail choice set increases satisfaction with and choice of the original, while a moderate-quality creative imitation does the opposite. Moreover, creative imitation affects consumers' satisfaction with the original by influencing whether their experience with the original verifies their expectations. Our paper reveals creative imitation effects to help incumbent firms effectively address them. Managerial Summary: When the incumbent is challenged by an entrant using creative imitation, consumers may react differently to the incumbent, and understanding consumers' reactions allows the incumbent to make better strategic decisions about how to address the challenge. Using lab and field experiments, we investigate creative imitations with two quality levels common in our empirical context, low quality and moderate quality, and examine how and why they differentially affect the originals. We find the presence of a low-quality creative imitation actually increased choice of the original by enhancing consumers' satisfaction with it, while a moderate-quality creative imitation reduced choice of the original by undermining satisfaction with it. Our research suggests the incumbent should address moderate-quality creative imitations' challenges to customer satisfaction, while temporarily tolerating low-quality creative imitations
Radiofrequency Ablation of Liver Cancer: Early Evaluation of Therapeutic Response with Contrast-Enhanced Ultrasonography
The early assessment of the therapeutic response after percutaneous radiofrequency (RF) ablation is important, in order to correctly decide whether further treatment is necessary. The residual unablated tumor is usually depicted on contrast-enhanced multiphase helical computed tomography (CT) as a focal enhancing structure during the arterial and portal venous phases. Contrast-enhanced color Doppler and power Doppler ultrasonography (US) have also been used to detect residual tumors. Contrast-enhanced gray-scale US, using a harmonic technology which has recently been introduced, allows for the detection of residual tumors after ablation, without any of the blooming or motion artifacts usually seen on contrast-enhanced color or power Doppler US. Based on our experience and reports in the literature, we consider that contrast-enhanced gray-scale harmonic US constitutes a reliable alternative to contrast-enhanced multiphase CT for the early evaluation of the therapeutic response to RF ablation for liver cancer. This technique was also useful in targeting any residual unablated tumors encountered during additional ablation
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