LLukas22/scidocs huggingface dataset:
Really Uncertain Business Cycles

We propose uncertainty shocks as a new impulse driving business cycles. First, we demonstrate that uncertainty, measured by a number of proxies is strongly countercyclical. Second, we build a dynamic stochastic general equilibrium model that extends the benchmark neoclassical growth model along two dimensions. It allows for the existence of heterogeneous rms with non-convex adjustment costs in both capital and labor and time-variation in uncertainty that is modeled as a change in the variance of innovations to productivity. We nd that increases in uncertainty lead to large drops in economic activity. This occurs because a rise in uncertainty makes rms cautious, leading them to pause hiring and investment. It also reduces the reallocation of capital and labor across rms, leading to large falls in productivity growth. Finally, we show that because uncertainty makes rms cautious it signicantly reduces the response of the economy to stimulative policy, leading to pro-cyclical policy multipliers. Keywords: uncertainty, adjustment costs and business cycles. JEL Classication: D92, E22, D8, C23. Disclaimer: Any opinions and conclusions expressed herein are those of the authors and do not necessarily represent the views of the U.S. Census Bureau. All results have been reviewed to ensure that no condential information is disclosed. We would like to thank our formal discussants Eduardo Engel at the AEA (2009) and Frank Smets at the ECB (2009) for their comments and suggestions. We thank Gadi Barlevy, Patrick Kehoe, and Naryana Kocherlakota for most helpful comments and suggestions. We would like to thank seminar participants at the AEA, ECB, UC-Irvine, IMF, Warwick University, Kellogg Business School of Management, NBER summer institute (2009). Correspondence: Nick Bloom, Department of Economics, Stanford University, Stanford, CA 94305, nbloom@stanford.edu.
A GIS data model for landmark-based pedestrian navigation

Landmarks provide the most predominant navigation cue for pedestrian navigation. Very few navigation data models in the geographical information science and transportation communities support modeling of landmarks and use of landmark-based route instructions for pedestrian navigation services. This article proposes a landmark-based pedestrian navigation data model to fill this gap. This data model can model landmarks in several pedestrian navigation scenarios (buildings, open spaces, multimodal transportation systems, and urban streets). This article implements the proposed model in the ArcGIS software environment and demonstrates two typical pedestrian navigation scenarios: (1) a multimodal pedestrian navigation environment involving bus lines, parks, and indoor spaces and (2) a subway system in a metropolitan environment. These two scenarios illustrate the feasibility of the proposed data model in real-world environments. Further improvements of this model could lead to more intuitive and user-friendly landmark-based pedestrian navigation services than the functions supported by current map-based navigation systems.
Trustworthiness in electronic commerce: the role of privacy, security, and site attributes

While the growth of business-to-consumer electronic commerce seems phenomenal in recent years, several studies suggest that a large number of individuals using the Internet have serious privacy concerns, and that winning public trust is the primary hurdle to continued growth in e-commerce. This research investigated the relative importance, when purchasing goods and services over the Web, of four common trust indices (i.e. (1) third party privacy seals, (2) privacy statements, (3) third party security seals, and (4) security features). The results indicate consumers valued security features significantly more than the three other trust indices. We also investigated the relationship between these trust indices and the consumer’s perceptions of a marketer’s trustworthiness. The findings indicate that consumers’ ratings of trustworthiness of Web merchants did not parallel experts’ evaluation of sites’ use of the trust indices. This study also examined the extent to which consumers are willing to provide private information to electronic and land merchants. The results revealed that when making the decision to provide private information, consumers rely on their perceptions of trustworthiness irrespective of whether the merchant is electronic only or land and electronic. Finally, we investigated the relative importance of three types of Web attributes: security, privacy and pleasure features (convenience, ease of use, cosmetics). Privacy and security features were of lesser importance than pleasure features when considering consumers’ intention to purchase. A discussion of the implications of these results and an agenda for future research are provided. q 2002 Elsevier Science B.V. All rights reserved.
Abnormal Structure and Function of the Esophagogastric Junction and Proximal Stomach in Gastroesophageal Reflux Disease

OBJECTIVES:This study applies concurrent magnetic resonance imaging (MRI) and high-resolution manometry (HRM) to test the hypothesis that structural factors involved in reflux protection, in particular, the acute insertion angle of the esophagus into the stomach, are impaired in gastroesophageal reflux disease (GERD) patients.METHODS:A total of 24 healthy volunteers and 24 patients with mild-moderate GERD ingested a test meal. Three-dimensional models of the esophagogastric junction (EGJ) were reconstructed from MRI images. Measurements of the esophagogastric insertion angle, gastric orientation, and volume change were obtained. Esophageal function was assessed by HRM. Number of reflux events and EGJ opening during reflux events were assessed by HRM and cine-MRI. Statistical analysis applied mixed-effects modeling.RESULTS:The esophagogastric insertion angle was wider in GERD patients than in healthy subjects (+7°±3°; P=0.03). EGJ opening during reflux events was greater in GERD patients than in healthy subjects (19.3 mm vs. 16.8 mm; P=0.04). The position of insertion and gastric orientation within the abdomen were also altered (both P<0.05). Median number of reflux events was 3 (95% CI: 2.5–4.6) in GERD and 2 (95% CI: 1.8–3.3) in healthy subjects (P=0.09). Lower esophageal sphincter (LES) pressure was lower (−11±2 mm Hg; P<0.0001) and intra-abdominal LES length was shorter (−1.0±0.3 cm, P<0.0006) in GERD patients.CONCLUSIONS:GERD patients have a wider esophagogastric insertion angle and have altered gastric morphology; structural changes that could compromise reflux protection by the “flap valve” mechanism. In addition, the EGJ opens wider during reflux in GERD patients than in healthy volunteers: an effect that facilitates volume reflux of gastric contents.
Evaluation of the effect of D-002, a mixture of beeswax alcohols, on osteoarthritis symptoms

BACKGROUND/AIMS
Nonsteroidal anti-inflammatory drugs relieve osteoarthritis (OA) symptoms but cause adverse effects. D-002, a mixture of beeswax alcohols, is effective against experimental OA. A pilot study found that D-002 (50 mg/day) for 8 weeks improves OA symptoms. The aim of this study was to investigate the effects of D-002 (50 to 100 mg/day) administered for 6 weeks on OA symptoms.


METHODS
Patients with OA symptoms were double-blindly randomized to D-002 (50 mg) or placebo for 6 weeks. Symptoms were assessed by the Western Ontario and McMaster Individual Osteoarthritis Index (WOMAC) and the visual analog scale (VAS) scores. Patients without symptom improvement at week 3 were titrated to two daily tablets. The primary outcome was the total WOMAC score. WOMAC pain, joint stiffness and physical function scores, VAS score, and use of rescue medications were secondary outcomes.


RESULTS
All randomized patients (n = 60) completed the study, and 23 experienced dose titration (two in the D-002 and 21 in the placebo groups). At study completion, D-002 reduced total WOMAC (65.4%), pain (54.9%), joint stiffness (76.8%), and physical function (66.9%) WOMAC scores, and the VAS score (46.8%) versus placebo. These reductions were significant beginning in the second week, and became enhanced during the trial. The use of rescue medication by the D-002 (6/30) group was lower than that in the placebo (17/30) group. The treatment was well tolerated. Seven patients (two in the D-002 and five in the placebo group) reported adverse events.


CONCLUSIONS
These results indicate that D-002 (50 to 100 mg/day) for 6 weeks ameliorated arthritic symptoms and was well tolerated.
FD-GAN: Pose-guided Feature Distilling GAN for Robust Person Re-identification

Person re-identification (reID) is an important task that requires to retrieve a person’s images from an image dataset, given one image of the person of interest. For learning robust person features, the pose variation of person images is one of the key challenges. Existing works targeting the problem either perform human alignment, or learn human-region-based representations. Extra pose information and computational cost is generally required for inference. To solve this issue, a Feature Distilling Generative Adversarial Network (FD-GAN) is proposed for learning identity-related and pose-unrelated representations. It is a novel framework based on a Siamese structure with multiple novel discriminators on human poses and identities. In addition to the discriminators, a novel same-pose loss is also integrated, which requires appearance of a same person’s generated images to be similar. After learning pose-unrelated person features with pose guidance, no auxiliary pose information and additional computational cost is required during testing. Our proposed FD-GAN achieves state-of-the-art performance on three person reID datasets, which demonstrates that the effectiveness and robust feature distilling capability of the proposed FD-GAN. ‡‡
Treatment planning for volumetric modulated arc therapy.

PURPOSE
Volumetric modulated arc therapy (VMAT) is a specific type of intensity-modulated radiation therapy (IMRT) in which the gantry speed, multileaf collimator (MLC) leaf position, and dose rate vary continuously during delivery. A treatment planning system for VMAT is presented.


METHODS
Arc control points are created uniformly throughout one or more arcs. An iterative least-squares algorithm is used to generate a fluence profile at every control point. The control points are then grouped and all of the control points in a given group are used to approximate the fluence profiles. A direct-aperture optimization is then used to improve the solution, taking into account the allowed range of leaf motion of the MLC. Dose is calculated using a fast convolution algorithm and the motion between control points is approximated by 100 interpolated dose calculation points. The method has been applied to five cases, consisting of lung, rectum, prostate and seminal vesicles, prostate and pelvic lymph nodes, and head and neck. The resulting plans have been compared with segmental (step-and-shoot) IMRT and delivered and verified on an Elekta Synergy to ensure practicality.


RESULTS
For the lung, prostate and seminal vesicles, and rectum cases, VMAT provides a plan of similar quality to segmental IMRT but with faster delivery by up to a factor of 4. For the prostate and pelvic nodes and head-and-neck cases, the critical structure doses are reduced with VMAT, both of these cases having a longer delivery time than IMRT. The plans in general verify successfully, although the agreement between planned and measured doses is not very close for the more complex cases, particularly the head-and-neck case.


CONCLUSIONS
Depending upon the emphasis in the treatment planning, VMAT provides treatment plans which are higher in quality and/or faster to deliver than IMRT. The scheme described has been successfully introduced into clinical use.
Putting people in the map: anthropogenic biomes of the world

© The Ecological Society of America www.frontiersinecology.org H have long distinguished themselves from other species by shaping ecosystem form and process using tools and technologies, such as fire, that are beyond the capacity of other organisms (Smith 2007). This exceptional ability for ecosystem engineering has helped to sustain unprecedented human population growth over the past half century, to such an extent that humans now consume about one-third of all terrestrial net primary production (NPP; Vitousek et al. 1986; Imhoff et al. 2004) and move more earth and produce more reactive nitrogen than all other terrestrial processes combined (Galloway 2005; Wilkinson and McElroy 2007). Humans are also causing global extinctions (Novacek and Cleland 2001) and changes in climate that are comparable to any observed in the natural record (Ruddiman 2003; IPCC 2007). Clearly, Homo sapiens has emerged as a force of nature rivaling climatic and geologic forces in shaping the terrestrial biosphere and its processes. Biomes are the most basic units that ecologists use to describe global patterns of ecosystem form, process, and biodiversity. Historically, biomes have been identified and mapped based on general differences in vegetation type associated with regional variations in climate (Udvardy 1975; Matthews 1983; Prentice et al. 1992; Olson et al. 2001; Bailey 2004). Now that humans have restructured the terrestrial biosphere for agriculture, forestry, and other uses, global patterns of species composition and abundance, primary productivity, land-surface hydrology, and the biogeochemical cycles of carbon, nitrogen, and phosphorus, have all been substantially altered (Matson et al. 1997; Vitousek et al. 1997; Foley et al. 2005). Indeed, recent studies indicate that human-dominated ecosystems now cover more of Earth’s land surface than do “wild” ecosystems (McCloskey and Spalding 1989; Vitousek et al. 1997; Sanderson et al. 2002, Mittermeier et al. 2003; Foley et al. 2005). It is therefore surprising that existing descriptions of biome systems either ignore human influence altogether or describe it using at most four anthropogenic ecosystem classes (urban/built-up, cropland, and one or two cropland/natural vegetation mosaic(s); classification systems include IGBP, Loveland et al. 2000; “Olson Biomes”, Olson et al. 2001; GLC 2000, Bartholome and Belward 2005; and GLOBCOVER, Defourny et al. 2006). Here, we present an alternate view of the terrestrial biosphere, based on an empirical analysis of global patterns of sustained direct human interaction with ecosystems, yielding a global map of “anthropogenic biomes”. We then examine the potential of anthropogenic biomes to serve as a new global framework for ecology, complete with CONCEPTS AND QUESTIONS
Evolutionary and Neo-Schumpeterian Approaches to Economics

1. The Neo-Schumpeterian and Evolutionary Approach to Economics - an Introduction L. Magnusson. Part I: Evolutionary Theory. 2. What is Evolutionary Economics? R. Langlois, M.J.Everett. 3. The Unit which Evolves: Linking Self-Reproduction and Self-Interest M. Hutter. 4. On the Nature of Economic Evolution: John R. Commons and the Metaphor of Artificial Selection Y. Ramstad. Part II: Neo-Schumpeterian Dynamics. 5. The Phenomenon of Economic Change: Neoclassical vs. Schumpeterian Approaches K. Dopfer. 6. The Theory of the Firm and the Theory of Economic Growth G. Eliasson. 7. Evolutionary Regimes and Industrial Dynamics G. Dosi, F. Malerba, L. Orsenigo. 8. The Role of Firm Difference in an Evolutionary Theory of Technical Advance R. Nelson. Part III: Critique and New Challenges. 9. The Integration of Theory and History: Methodology and Ideology in Schumpeter's Economics W. Lazonick. 10. Neo-Schumpeterians and Economic Theory A. Heertje. Rethinking Economics. From GNP-Growth to Ecological Sustainability P. Soderbaum. Innovations and Institutions: an Historical Approach L. Magnusson, G. Marklund. Index.
Carbonatites in a subduction system: The Pleistocene alvikites from Mt. Vulture (southern Italy)

We report here, for the first time, on the new finding of extrusive calciocarbonatite (alvikite) rocks from the Pleistocene Mt. Vulture volcano (southern Italy). These volcanic rocks, which represent an outstanding occurrence in the wider scenario of the Italian potassic magmatism, form lavas, pyroclastic deposits, and feeder dikes exposed on the northern slope of the volcano. The petrography, mineralogy and whole-rock chemistry attest the genuine carbonatitic nature of these rocks, that are characterized by high to very high contents of Sr, Ba, U, LREE, Nb, P, F, Th, high Nb/Ta and LREE/HREE ratios, and low contents of Ti, Zr, K, Rb, Na and Cs. The O–C isotope compositions are close to the “primary igneous carbonatite” field and, thus, are compatible with an ultimate mantle origin for these rocks. The Sr–Nd–Pb–B isotope compositions, measured both in the alvikites and in the silicate volcanic rocks, indicate a close genetic relationship between the alvikites and the associated melilitite/nephelinite rocks. Furthermore, these latter products are geochemically distinct from the main foiditic-phonolitic association of Mt. Vulture. We propose a petrogenetic/geodynamic interpretation which has important implications for understanding the relationships between carbonatites and orogenic activity. In particular, we propose that the studied alvikites are generated through liquid unmixing at crustal levels, starting from nephelinitic or melilititic parent liquids. These latter were produced in a hybrid mantle resulting from the interaction through a vertical slab window, between a metasomatized mantle wedge, moving eastward from the Tyrrhenian/ Campanian region, and the local Adriatic mantle. The occurrence of carbonatite rocks at Mt. Vulture, that lies on the leading edge of the Southern Apennines accretionary prism, is taken as an evidence for the carbonatation of the mantle sources of this volcano. We speculate that mantle carbonatation is related to the introduction of sedimentary carbon from the Adriatic lithosphere during Tertiary subduction. © 2007 Elsevier B.V. All rights reserved.
Clinical and genetic outcome determinants of Internet- and group-based cognitive behavior therapy for social anxiety disorder.

OBJECTIVE
No study has investigated clinical or genetic predictors and moderators of Internet-based cognitive behavior therapy (ICBT) compared with cognitive behavioral group therapy for (CBGT) for SAD. Identification of predictors and moderators is essential to the clinician in deciding which treatment to recommend for whom. We aimed to identify clinical and genetic (5-HTTLPR, COMTval158met, and BDNFval66met) predictors and moderators of ICBT and CBGT.


METHOD
We performed three types of analyses on data from a sample comprising participants (N = 126) who had undergone ICBT or CBGT in a randomized controlled trial. Outcomes were i) end state symptom severity, ii) SAD diagnosis, and iii) clinically significant improvement.


RESULTS
The most stable predictors of better treatment response were working full time, having children, less depressive symptoms, higher expectancy of treatment effectiveness, and adhering to treatment. None of the tested gene polymorphisms were associated with treatment outcome. Comorbid general anxiety and depression were moderators meaning that lower levels were associated with a better treatment response in ICBT but not in CBGT.


CONCLUSION
We conclude that demographic factors, symptom burden, adherence, and expectations may play an important role as predictors of treatment outcome. The investigated gene polymorphisms do not appear to make a difference.
Vascular heterogeneity between native rat pancreatic islets is responsible for differences in survival and revascularisation post transplantation

Highly blood-perfused islets have been observed to be the most functional islets in the native pancreas. We hypothesised that differences in vascular support of islets in donor pancreases influence their susceptibility to cellular stress and capacity for vascular engraftment after transplantation. Highly blood-perfused islets in rats were identified by injection of microspheres into the ascending aorta before islet isolation. Cell death was evaluated after in vitro cytokine or hypoxia exposure, and 2 days post transplantation. One month post transplantation, islet engraftment, including vascular density, blood perfusion and oxygen tension (pO2) in the tissue, was evaluated. Microsphere-containing islets had a similar frequency of cell death during standard culture conditions but increased cell death after exposure to cytokines and hypoxia in comparison with other islets. Two days after transplantation the percentage of apoptotic or necrotic cells was also higher in grafts of such islets and 1 month post transplantation these grafts were composed of substantially more connective tissue. Grafts of highly blood-perfused islets in the native pancreas regained a higher vascular density, blood perfusion and pO2 in comparison with grafts of other islets. Native islets that are highly blood-perfused regained this feature after transplantation, indicating a superior capacity for revascularisation and post-transplant function. However, the same group of islets was more vulnerable to different kinds of cellular stress, which limited their early survival post transplantation. Preferential death of these most active islets may contribute to the high number of islets needed to provide cure with islet transplantation.
Biomarker-calibrated dietary energy and protein intake associations with diabetes risk among postmenopausal women from the Women's Health Initiative.

BACKGROUND
Self-report of dietary energy and protein intakes has been shown to be systematically and differentially underreported.


OBJECTIVE
We assessed and compared the association of diabetes among postmenopausal women with biomarker-calibrated and uncalibrated dietary energy and protein intakes from food-frequency questionnaires (FFQs).


DESIGN
The analyses were performed for 74,155 participants of various race-ethnicities from the Women's Health Initiative. Uncalibrated and calibrated energy and protein intakes from FFQs were assessed for associations with incident diabetes by using HR estimates based on Cox regression.


RESULTS
A 20% increment in uncalibrated energy consumption was associated with increased diabetes risk (HR) of 1.03 (95% CI: 1.01, 1.05), 2.41 (95% CI: 2.06, 2.82) with biomarker calibration, and 1.30 (95% CI: 0.96, 1.76) after adjustment for BMI. A 20% increment in uncalibrated protein (g/d) resulted in an HR of 1.05 (95% CI: 1.03, 1.07), 1.82 (95% CI: 1.56, 2.12) with calibration, and 1.16 (95% CI: 1.05, 1.28) with adjustment for BMI. A 20% increment in uncalibrated protein density (% of energy from protein) resulted in an HR of 1.13 (95% CI: 1.09, 1.17), 1.01 (95% CI: 0.75, 1.37) with calibration, and 1.19 (95% CI: 1.07, 1.32) with adjustment for BMI.


CONCLUSIONS
Higher protein and total energy intakes (calibrated) appear to be associated with a substantially increased diabetes risk that may be mediated by an increase in body mass over time. Diet-disease associations without correction of self-reported measurement error should be viewed with caution. This trial is registered at clinicaltrials.gov as NCT00000611.
Life cycle welfare: evidence and conjecture

Abstract At a point in time subjective well-being is positively related to income; over the life course subjective well-being is constant despite substantial growth in income. This paradox is explained by new evidence on consumption aspirations. At a point in time aspirations vary fairly little by income level; over the life cycle, aspirations increase about in proportion to income. These shifts in aspirations also affect assessments of past and future well-being in such a way that the choices underlying behavior (based on what psychologists call “decision utility”) turn out not to have their expected welfare effects (experienced utility). Of the two influences shaping consumption aspirations – comparisons with others and with one’s past experience – the former appears more salient early in the life cycle and the latter, later on.