cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The biosynthesis of deoxyribonucleic acid in vivo in the intestinal mucosa of rat
Creators: name: Mezei, Catherine
Publisher: name: University of British Columbia
Year: 2011

description: The in vivo biosynthesis of deoxyribonucleic acid (DNA) from labelled thymidine has been investigated in rat intestinal mucosa. The DNA preparations were fractionated by column chromatography and the fractions were assayed for radioactivity by liquid scintillation counting methods. In the first experiments the DNA was isolated from the intestinal mucosa of rats which had received H³-thymidine 5, 10 or 20 minutes or 24 hours before sacrifice. When the macromolecules were fractionated on ECTEOLA-cellulose the results obtained were inconclusive because no definits pattern of incorporation of radioactivity was observed in the fractions. Chromatography on ECTEOLA-cellulose was considered unsatisfactory, because of the variations in the elution patterns of DNA preparations from experiment to experiment and evidence indicating degradation of DNA during the fractionation procedure. In subsequent experiments fractionation on methylated albumin-kieselguhr (MAK) columns was employed and double labelling experiments were carried out. The animals were injected intravenously with H³-thymidine and 24 hours later with C¹⁴-thymidine. The rats were killed 20 or 40 minutes after the second injection and the double labelled DNA was isolated from the intestinal mucosa. On fractionation by MAK columns reproducible elution patterns were obtained even after storage of the DNA solutions. The main DNA peak was always eluted at the same range of sodium chloride concentration and 95-97 percent of the radioactivity was eluted in this peak. Each subfraction comprising the main peak was examined for H³ and C¹⁴ activity. By studying the H³/C¹⁴ ratios of the fractions newly synthesized material could be compared with older, presumably stabilized DNA. When the animals were exposed to the C¹⁴-labelled thymidine for 40 minutes the H³/C¹⁴ ratios of the subfractions were constant, indicating no metabolic differences between the newly synthesized DNA (C¹⁴-labelled and the "old" (H³-labelled) DNA. However, when the time of exposure to the C¹⁴-labelled precursor in vivo was 20 minutes, the H³ /C¹⁴ ratios of subtractions increased as the sodium chloride concentration of the eluant increased. These results indicated some metabolic differences amongst these fractions. Stepwise enzymatic degradation by snake venom phosphodiesterase of the double labelled DNA preparations, and the main peak obtained after MAK chromatography, indicated the incorporation of thymidine into newly synthesized and "old" DNA occurred well within the chain.
Elasticity management for capacity planning in software as a service cloud computing
Creators: name: Stauffer, Jon M.
name: Megahed, Aly
name: Sriskandarajah, Chelliah
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Medicine
subject: Ecology
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: Computational Biology

description: Applications of cloud computing are increasing as companies shift from on-premise IT environments to public, private, or hybrid clouds. Consequently, cloud providers use capacity planning to maintain the capacity of computing resources (instances) required to meet the dynamic nature of the demand (queries). However, there is a trade-off between deploying too many costly instances, and deploying too few instances and paying penalties for not being able to process queries on-time. An instance has multiple resource dimensions and executing a query consumes multiple dimensions of an instance’s capacity. This detailed multi-dimensional management of cloud computing resource capacity is known as elasticity management and is an important issue faced by all cloud providers. Determining the optimal number of instances needed in a given planning horizon is challenging, due to the combinatorial nature of the optimization problem involved. We develop an optimization model and related algorithms to capture the trade-off between the resource cost versus the delayed execution penalty in software as a service applications from the cloud provider’s perspective. We develop an exact approach to solve small to medium sized applications and heuristics to solve large applications. We then evaluate their performance via extensive computational analyses with real-world data and current cloud provider approaches. We also develop a stochastic framework and methodology to deal with demand uncertainty, and using two different randomly generated data sets (representing problem instances in practice), we demonstrate that robust solutions can be obtained.
MOND and the Galaxies
Creators: name: Combes, F.
name: Tiret, O.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We review galaxy formation and dynamics under the MOND hypothesis of modified gravity, and compare to similar galaxies in Newtonian dynamics with dark matter. The aim is to find peculiar predictions both to discriminate between various hypotheses, and to make the theory progress through different constraints, touching the interpolation function, or the fundamental acceleration scale. Galaxy instabilities, forming bars and bulges at longer term, evolve differently in the various theories, and help to bring constraints, together with the observations of bar frequency. Dynamical friction and the predicted merger rate could be a sensitive test of theories. The different scenarios of galaxy formation are compared within the various theories and observations.
description: 8 pages, 7 figures, Invited paper to "The Invisible Universe International Conference", ed. J-M. Alimi, A. Fuzfa, P-S. Corasaniti, AIP pub
Left ventricle hydatid cyst
Creators: name: Faizi, Ahmad Reshad
Publisher: name: EURORAD
Year: 2015
Subjects: subject: Abdomen
subject: Cardiovascular system
subject: CT
subject: Biopsy
subject: Comparative studies
subject: Computer Applications-3D
subject: Abscess
subject: Cysts
subject: Metastases

description: Clinical History Image Findings Discussion Find Diagnosis Differential Diagnosis
description: female, 22 years
description: Clinical History: A 22-year-old female patient presented with right upper quadrant pain and chest pain. Her past medical history was unremarkable. Final Diagnosis: Left ventricle hydatid cyst
Cutting planes for security-constrained unit commitment with regulation reserve
Creators: name: Jianqiu Huang
name: Pan, Kai
name: Yongpei Guan
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Pharmacology
subject: Sociology
subject: FOS: Sociology
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: Computational Biology

description: With significant economic and environmental benefits, renewable energy is increasingly used to generate electricity. To hedge against the uncertainty due to the increasing penetration of renewable energy, an ancillary service market was introduced to maintain reliability and efficiency, in addition to day-ahead and real-time energy markets. To co-optimize these two markets, a unit commitment problem with regulation reserve (the most common ancillary service product) is solved for daily power system operations, leading to a large-scale and computationally challenging mixed-integer program. In this article, we analyze the polyhedral structure of the co-optimization model to speed up the solution process by deriving problem-specific strong valid inequalities. Convex hull results for certain special cases (i.e., two- and three-period cases) with rigorous proofs are provided, and strong valid inequalities covering multiple periods under the most general setting are derived. We also develop efficient polynomial-time separation algorithms for the inequalities that are in the exponential size. We further tighten the formulation by deriving an extended formulation for each generator in a higher-dimensional space. Finally, we conduct computational experiments to apply our derived inequalities as cutting planes in a branch-and-cut algorithm. Significant improvement from our inequalities over commercial solvers demonstrates the effectiveness of our approach, leading to practical usefulness to enhance the co-optimization of energy and ancillary service markets.
Uniform Large deviations for infinite dimensional stochastic systems with jumps
Creators: name: Maroulas, Vasileios
Publisher: name: arXiv
Year: 2010
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics

description: Uniform large deviation principles for positive functionals of all equivalent types of infinite dimensional Brownian motions acting together with a Poisson random measure are established. The core of our approach is a variational representation formula which for an infinite sequence of i.i.d real Brownian motions and a Poisson random measure was shown in [5].
New Developments in Papua New Guinea's Research and Development Regulatory Framework
Creators: name: Forsyth, Miranda
Publisher: name: Canberra, ACT : Coral Bell School of Asia Pacific Affairs, College of Asia and the Pacific, The Australian National University
Year: 2016

description: This In Brief updates In Brief 2015/24 that first reported on the emergence of a new regulatory framework around research and development in Papua New Guinea (PNG). It outlines developments in this area over the past 18 months, including the most recent event, the National Forum on Intellectual Property and Research and Development, held in Port Moresby 1–2 September 2016. It is important that researchers, donor agencies and PNG government departments are aware of these developments because once the new arrangements are in place they will have considerable impact upon the regulation of research and development in PNG. For instance, there will be greater national coordination of research and more requirements on researchers to pay attention to the national research priorities and comply with codes of ethical practice.
Iatrogenic oesophageal perforation after pneumatic balloon dilatation for achalasia
Creators: name: Tonolini, Massimo
Publisher: name: EURORAD
Year: 2015
Subjects: subject: Mediastinum
subject: Oesophagus
subject: CT
subject: CT-Angiography
subject: Fluoroscopy
subject: Plain radiographic studies
subject: Complications
subject: Dilation
subject: Dynamic swallowing studies
subject: Dilatation
subject: Motility

description: Clinical History Image Findings Discussion Find Diagnosis Differential Diagnosis
description: male, 83 years
description: Clinical History: Elderly male suffering from malaise, limited oral intake and weight loss since a few months, recently diagnosed with achalasia. Several comorbidities including atrial fibrillation, congestive heart failure, multifactorial anaemia, melaena from bleeding me... Final Diagnosis: Iatrogenic esophageal perforation after balloon dilatation for achalasia. Conservative treatment.
Supplementary document for Keyframe-aided resolution enhancement network for dynamic super-resolution structured illumination microscopy - 6389451.pdf
Creators: name: Tang, Yujun
name: Wen, Gang
name: Liang, Yong
name: Wang, Linbo
name: zhang, Jie
name: li, Hui
Publisher: name: Optica Publishing Group
Year: 2023
Subjects: Uncategorized

description: revised supplemental document
Inventory rationing on a one-for-one inventory model for two priority customer classes with backorders and lost sales
Creators: name: Oguzhan Vicil
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Medicine
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics
subject: Science Policy

description: In this study, we are primarily motivated by the research problem of recognizing heterogeneous customer behavior towards waiting for order fulfillment under the threshold rationing policy (also known as the critical level policy), and aim to find its effect on system stock levels and performance measures. We assume a continuous review one-for-one ordering policy with generally distributed lead times. In the first model, we consider the case in which the low-priority customer class exhibits zero patience for waiting if the demand is not satisfied immediately (a lost sale), whereas the demand of the high-priority customer class can be backordered. This is the first study in the literature to consider this model. We provide an exact analysis for the derivation of the steady-state probability distribution and the average infinite horizon cost per unit time. We then develop an efficient optimization procedure to minimize the average expected cost rate. We also determine the forms of the optimal solutions for the two service level optimization models that are common in practice. In the second model, we study the opposite case in which the high-priority customer class exhibits zero patience for waiting. We establish a theoretical basis for the rationale of using the Continuous-Time Markov Chain (CTMC) approach as an approximation. We show that under certain assumptions, the steady-state probabilities of the system with generally distributed lead times are identical to the steady-state probabilities of the CTMC system with the same mean. This result enables us to link the dynamics of the studied model to the CTMC model, which may open new doors for future research.
Point prevalence probing of antimicrobial prescription patterns from a developing country
Creators: name: Khursheed, Nazia
name: Ahsan, Qadeer
name: Rattani, Salima
name: Fatima, Madeeha
name: Raza, Ali
name: Tariq, Saba
name: Mustafa, Tauqeer
name: Ahmed, Kamran
name: Iqbal, Sadia
name: Zulfiqar, Sibgha
name: Ahmed, Syed Masroor
name: Fatima, Ghulam
name: Khan, Shehzad Akbar
name: Ullah, Farman
name: Ahmed, Rana Altaf
name: Jamal, Saba
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Pharmacology
subject: Biotechnology
subject: Chemical Sciences not elsewhere classified
subject: Immunology
subject: FOS: Clinical medicine
subject: Marine Biology
subject: Science Policy
subject: Infectious Diseases
subject: FOS: Health sciences
subject: Virology
subject: Computational Biology

description: Irrational use of antibiotics intensifies resistance and jeopardizes advances made in modern medicine. We aimed to conduct a baseline gap analysis survey on antibiotic prescription practices across Pakistan. This multi-centered cross-sectional survey was conducted at six public sector tertiary care hospitals from February 2021 to March 2021. Data related to various variables including hospital infrastructure, policies and practices, monitoring and feedback, and epidemiological, clinical, and antibiotic prescription for surveyed patients was collected using World Health Organization (WHO) Point Prevalence Survey (PPS) methodology. In a survey of 837 inpatients, 78.5% were prescribed antibiotics. Most commonly prescribed antimicrobial was ceftriaxone (21.7%), followed by metronidazole (17.3%), cefoperazone-sulbactam (8.4%), amoxicillin-clavulanate (6.3%), and piperacillin/tazobactam (5.9%). Surgical prophylaxis (36.7%) and community-acquired infections (24.7%) were the main reasons for antibiotic prescriptions. Single antibiotics were given to 46.7% of patients, 39.9% received a combination of two antibiotics, and 12.5% were prescribed three or more antibiotics. Among six hospitals surveyed, two had drug and therapeutic committees, three had infection prevention and control committees, and one had an antibiotic formulary. Findings demonstrate high consumption of broad-spectrum antimicrobials and emphasize the importance of expanding antimicrobial stewardship programs among hospitals. Mentoring clinical teams could help rationalize antimicrobial use.
An iterative filter to reconstruct planetary transit signals in the presence of stellar variability
Creators: name: Alapini, A.
name: Aigrain, S.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The detrending algorithms which are widely used to reduce the impact of stellar variability on space-based transit surveys are ill-suited for estimating the parameters of confirmed planets, as they unavoidably alter the transit signal. We present a post-detection detrending algorithm, which filters out signal on other timescales than the period of the transit while preserving the transit signal. We compare the performance of this new filter to a well-established pre-detection detrending algorithm, by applying both to a set of 20 simulated light curves containing planetary transits, stellar variability, and instrumental noise as expected for the CoRoT space mission, and performing analytic fits to the transits. Compared to the pre-detection benchmark, the new post-detection filter systematically yields significantly reduced errors (median reduction in relative error over our sample of about 40%) on the planet-to-star radius ratio, system scale and impact parameter. This is particularly important for active stars, where errors induced by variability can otherwise dominate the final error budget on the planet parameters. Aside from improving planet parameter estimates, the new filter preserves all signal at the orbital period of the planet, and thus could also be used to search for light reflected by the planet.
description: 16 pages, 6 figures, accepted for publication in MNRAS
An investigation of academic post-secondary school students in King Edward Senior Matriculation and Continuing Education Centre
Creators: name: Glenesk, Alfred H.
Publisher: name: University of British Columbia
Year: 2011

description: This study seeks to discover any significant differences among the participants of three types of educational programs at King Edward Senior Matriculation and Continuing Education Centre. Selected measurable characteristics of these post-secondary students are tested in order to investigate any differences among the participants at the Centre. The data chosen include various performance factors of continuing education participants. These characteristic factors of student behavior were coded for use in the key-sort cards, and tabulated for electronic processing and statistical analysis. The chi-square test and the "t" test were applied to the data to test for significant differences among the three types of participants in a post-secondary school. Relationships within groups and between groups were further tested by the Pearson product-moment coefficient of correlation using three selected factors: grade-point average, intelligence quotient, and final achievement. The null hypothesis was upheld in most instances, and evidence could not be found that any single factor tested other than final achievement contributed to distinguishing young adults on the basis of the educational measurements selected. Further research into other characteristics of adult learners might more clearly account for differences in academic performance. Of the three groups of participants which were analysed, the senior matriculation students were more distinct and had characteristics which were more singularly predictable when related to the criterion of success on a final examination than the interrupted program students or the grade XII students.
Accelerated Componentwise Gradient Boosting Using Efficient Data Representation and Momentum-Based Optimization
Creators: name: Schalk, Daniel
name: Bischl, Bernd
name: Rügamer, David
Publisher: name: Taylor & Francis
Year: 2022
Subjects: subject: Neuroscience
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics

description: Componentwise boosting (CWB), also known as model-based boosting, is a variant of gradient boosting that builds on additive models as base learners to ensure interpretability. CWB is thus often used in research areas where models are employed as tools to explain relationships in data. One downside of CWB is its computational complexity in terms of memory and runtime. In this article, we propose two techniques to overcome these issues without losing the properties of CWB: feature discretization of numerical features and incorporating Nesterov momentum into functional gradient descent. As the latter can be prone to early overfitting, we also propose a hybrid approach that prevents a possibly diverging gradient descent routine while ensuring faster convergence. Our adaptions improve vanilla CWB by reducing memory consumption and speeding up the computation time per iteration (through feature discretization) while also enabling CWB learn faster and hence to require fewer iterations in total using momentum. We perform extensive benchmarks on multiple simulated and real-world datasets to demonstrate the improvements in runtime and memory consumption while maintaining state-of-the-art estimation and prediction performance.
Robust inference on income inequality: t-statistic based approach
Creators: name: Ibragimov, Rustam
name: Kattuman, Paul
name: Skrobotov, Anton
Publisher: name: Taylor & Francis
Year: 2025
Subjects: subject: Medicine
subject: Sociology
subject: FOS: Sociology
subject: Biological Sciences not elsewhere classified
subject: Mathematical Sciences not elsewhere classified
subject: Science Policy

description: Empirical analyses of income and wealth inequality often face the difficulty that the observations are heterogeneous, heavy-tailed, or correlated in some unknown fashion. This article focuses on applications of the recently developed computationally simple t-statistic based robust inference approach to the analysis of inequality. Two regions can be compared in terms of inequality as follows: the data in the samples relating to the two regions are partitioned into small numbers of groups, and the chosen inequality index/measure is estimated for each group. Inference is then based on standard t-tests with the resulting group estimators. The t-statistic based approach results in valid inference, as long as the group estimators of the inequality index are asymptotically independent, unbiased, and Gaussian, possibly with different variances. These conditions are typically satisfied in empirical applications. The presented method complements and compares favorably with other approaches to inference on inequality. We apply this approach to examine income inequality across Russian regions. Our analysis reveals that income distribution in Russia is notably heavy-tailed, with most regions exhibiting higher levels of inequality compared to Moscow. Robust comparisons of this type offer a good foundation for evaluating and shaping regional policies aimed at addressing income disparities.
Voting in agreeable societies
Creators: name: Berg, Deborah E.
name: Norine, Serguei
name: Su, Francis Edward
name: Thomas, Robin
name: Wollan, Paul
Publisher: name: arXiv
Year: 2008
Subjects: subject: Combinatorics (math.CO)
subject: History and Overview (math.HO)
subject: FOS: Mathematics
subject: 52A35, 91B12

description: When can a majority of voters find common ground, that is, a position they all agree upon? How does the shape of the political spectrum influence the outcome? When mathematical objects have a social interpretation, the associated theorems have social applications. In this article we give examples of situations where sets model preferences and develop extensions of classical theorems about convex sets, such as Helly's theorem, that can be used in the analysis of voting in "agreeable" societies.
description: 13 pages, 8 figures; to appear, Amer. Math. Monthly. Related work at http://www.math.hmc.edu/~su/papers.html
Specialist care in rural hospitals: From Emergency Department consultation to hospital discharge
Creators: name: Klein, Michael G.
name: Verter, Vedat
name: Hughie F. Fraser
name: Moses, Brian G.
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Medicine
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: Sociology
subject: FOS: Sociology
subject: Cancer
subject: Science Policy
subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: Computational Biology

description: In urban and rural hospitals, congested Emergency Departments (EDs) are filled with patients boarding in the ED awaiting admission to inpatient wards. We study this problem beyond the walls of the ED, examining the multi-departmental process managed by specialists. In rural hospitals, an Internal Medicine Specialist (Internist) commonly serves simultaneously as both the Intensive Care Unit (ICU) physician and Internist on call. We develop a stochastic dynamic programming framework for specialists’ workflow decisions and apply it to data sets developed from two rural hospitals. One uses the dual role approach and the other, similar to urban hospitals, staffs the ICU with another physician, each with a single role. Our empirical results show that, excluding an overnight batch, arrivals of ED consultation requests for rural specialists follow a homogeneous Poisson process. Our models help identify better policies and determine how much better off a hospital is with two rather than one Internist on call. Although current guidelines suggest an early inpatient discharge strategy, we find that specialists should give higher priority to ED consultations unless a threshold number of patients are boarding in the ED or until a threshold time of day when specialists should give higher priority to inpatient discharges.
Gluon masses without seagull divergences
Creators: name: Papavassiliou, Joannis
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The study of dynamical gluon mass generation at the level of Schwinger-Dyson equation involves a delicate interplay between various field-theoretic mechanisms The underlying local gauge invariance remains intact by resorting to the well-known Schwinger mechanism, which is assumed to be realized by longitudinally coupled bound state poles, produced by the non-perturbative dynamics of the theory. These poles are subsequently included into the Schwinger-Dyson equation of the gluon propagator through the three-gluon vertex, generating a non-vanishing gluon mass, which, however, is expressed in terms of divergent seagull integrals. In this talk we explain how such divergences can be eliminated completely by virtue of a characteristic identity, valid in dimensional regularization. The ability to trigger this identity depends, in turn, on the details of the three-gluon vertex employed, and in particular, on the exact way the bound state poles are incorporated. A concrete example of a vertex that triggers the aforementioned identity is constructed, the ensuing cancellation of all seagull divergences is explicitly demonstrated, and a finite gluon mass is obtained. Due to the multitude of conditions that must be simultaneously satisfied, this construction appears to be exclusively realized within the PT-BFM framework. The resulting system of integral equations gives rise to a gluon mass that displays power-law running and an effective charge which, due to the presence of the gluon mass, freezes in the infrared at a finite (non-vanishing) value.
description: 12 pages, 5 figures. Talk presented at the International Workshop on QCD Green's Functions, Confinement, and Phenomenology - QCD-TNT09, September 07 - 11 2009, ECT* Trento, Italy
Price discounts and personalized product assortments under multinomial logit choice model: A robust approach
Creators: name: Qingwei Jin
name: Jen-Yen Lin
name: Zhou, Sean X.
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Sociology
subject: FOS: Sociology
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics
subject: Computational Biology

description: With increasing availability of consumer data and rapid advancement and application of technologies, online retailers are gaining better knowledge of customers’ shopping behavior and preferences. Thus more and more retailers are providing personalized product assortment to better match the needs of customers and generate more sales. In this article, we study a two-stage revenue management model. In the first stage, the retailer decides non-personalized price discounts for each product. In the second stage (upon the arrival of customers), the retailer offers a personalized assortment to each type of customer. Based on this assortment, the customer then makes a purchase decision according to the Multinomial logit choice model. We employ a robust approach for the joint discounts and personalized assortment optimization problem in order to handle data uncertainty from estimating customer preferences and distribution of different customer segments. We analyze the structural properties of the problems and propose efficient computational methods to solve the problems with/without a cardinality constraint on the assortment. In certain cases, our algorithm converges at a superlinear rate. When there is a cardinality constraint on the assortment, we find that the retailer should offer greater discounts as the constraint becomes more restrictive. We also discuss the value of our robust solution and the extension of when the customer discount sensitivity function is also uncertain. Finally, our extensive numerical study shows that the solutions under the robust approach perform very well when compared to the one assuming accurate information, and are robust when there is uncertainty.
Testing for nonlinear cointegration under heteroskedasticity
Creators: name: Hanck, Christoph
name: Massing, Till
Publisher: name: Taylor & Francis
Year: 2024
Subjects: subject: Medicine
subject: Physiology
subject: FOS: Biological sciences
subject: Sociology
subject: FOS: Sociology
subject: Mathematical Sciences not elsewhere classified
subject: Science Policy

description: This article discusses Shin (1994, Econometric Theory)-type tests for nonlinear cointegration in the presence of variance breaks. We build on cointegration test approaches under heteroskedasticity (Cavaliere and Taylor, 2006, Journal of Time Series Analysis) and nonlinearity, serial correlation, and endogeneity (Choi and Saikkonen, 2010, Econometric Theory) to propose a bootstrap test and prove its consistency. A Monte Carlo study shows the approach to have satisfactory finite-sample properties in a variety of scenarios. We provide an empirical application to the environmental Kuznets curves (EKC), finding that the cointegration test provides little evidence for the EKC hypothesis. Additionally, we examine a nonlinear relation between the US money demand and the interest rate, finding that our test does not reject the null of a smooth transition cointegrating relation.
Testing the endogeneity of a spatial weight matrix in the weak-tied spatial dynamic panel data model
Creators: name: Lee, Jieun
Publisher: name: Taylor & Francis
Year: 2024
Subjects: subject: Medicine
subject: Environmental Sciences not elsewhere classified
subject: Sociology
subject: FOS: Sociology
subject: Biological Sciences not elsewhere classified
subject: Mathematical Sciences not elsewhere classified

description: Weak ties in large-scale networks facilitate the diffusion of information and resources, generating spillover effects. While geographic proximity may generate straightforward networks, a non predetermined spillover framework better accommodates socioeconomic interactions. In such cases, it is important to test the endogeneity of a spatial weight matrix before full estimation to ensure valid and efficient model selection. I propose a robust score test to assess this endogeneity in the weak-tied spatial dynamic panel data model, emphasizing its asymptotic optimality and computational efficiency. First, I correct score function biases to address the incidental parameters problem. Second, I adjust the score functions to enhance robustness against local parametric misspecifications. Monte Carlo simulations demonstrate favorable finite sample properties. In my application, I illustrate how this test helps model selection for the Solow-Swan growth model, considering spillovers from geographic and knowledge proximities. The estimation results reveal endogenous spillover effects with weakly positive impacts on real income per worker, while savings show positive internal effects but negative spillover effects, possibly due to competition for investment. Notably, the labor growth rate positively influences knowledge accumulation and innovation, leading to beneficial effects on real income per worker through both internal and spillover channels.
Accelerated Componentwise Gradient Boosting using Efficient Data Representation and Momentum-based Optimization
Creators: name: Schalk, Daniel
name: Bischl, Bernd
name: Rügamer, David
Publisher: name: Taylor & Francis
Year: 2022
Subjects: subject: Neuroscience
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics

description: Componentwise boosting (CWB), also known as model-based boosting, is a variant of gradient boosting that builds on additive models as base learners to ensure interpretability. CWB is thus often used in research areas where models are employed as tools to explain relationships in data. One downside of CWB is its computational complexity in terms of memory and runtime. In this paper, we propose two techniques to overcome these issues without losing the properties of CWB: feature discretization of numerical features and incorporating Nesterov momentum into functional gradient descent. As the latter can be prone to early overfitting, we also propose a hybrid approach that prevents a possibly diverging gradient descent routine while ensuring faster convergence. Our adaptions improve vanilla CWB by reducing memory consumption and speeding up the computation time per iteration (through feature discretization) while also enabling CWB learn faster and hence to require fewer iterations in total using momentum. We perform extensive benchmarks on multiple simulated and real-world data sets to demonstrate the improvements in runtime and memory consumption while maintaining state-of-the-art estimation and prediction performance.
Hidden symmetries of integrable conformal mechanical systems
Creators: name: Hakobyan, Tigran
name: Krivonos, Sergey
name: Lechtenfeld, Olaf
name: Nersessian, Armen
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We split the generic conformal mechanical system into a "radial" and an "angular" part, where the latter is defined as the Hamiltonian system on the orbit of the conformal group, with the Casimir function in the role of the Hamiltonian. We reduce the analysis of the constants of motion of the full system to the study of certain differential equations on this orbit. For integrable mechanical systems, the conformal invariance renders them superintegrable, yielding an additional series of conserved quantities originally found by Wojciechowski in the rational Calogero model. Finally, we show that, starting from any N=4 supersymmetric "angular" Hamiltonian system one may construct a new system with full N=4 superconformal D(1,2;α) symmetry.
description: 9 pages revtex
title: Exploring the prosocial effects of moral elevation in middle childhood and early adolescence
Creators: name: Ali, Shazza
Publisher: name: University of Kent
Year: 2021

description: A growing body of research has explored the impact of moral elevation - the emotional response to witnessing acts of moral virtue, or moral beauty, such as giving and kindness - on prosocial behaviour in adulthood, however much less is known about the experience and effects of moral elevation in a younger age group. This thesis examines the effect of moral elevation on prosociality in childhood and adolescence. Chapter 1 is a theoretical chapter that reviews the relevant literature on prosocial behaviour, the appraisal tendency framework (e.g., Lerner & Keltner, 2000) and moral emotions, specifically moral elevation. Chapter 1 also includes an overview of the empirical research that follows in Chapters 2, 3, 4 and 5. In Chapter 2 and 3, we test the effects of moral elevation on general and intergroup prosociality. We find that moral elevation increases general prosocial motivation (Study 1, 5-11-year-olds, N=91; Study 3, 13-14-year-olds, N=150) and outgroup prosocial motivation and behaviour (Study 2, 5-11-year-olds, N=125). In Chapter 4, we explore the (dis)similarities of the experience of moral elevation and admiration (Study 4, 5-11-year-olds, N=213; Study 5, 9-11-year-olds, N=203). These studies show that cognitive appraisals, and subsequent motivations associated with moral elevation and admiration differ, and that differences may become more pronounced between mid to late childhood. In Chapter 5, we test the effects of a longitudinal intervention designed to increase engagement with moral beauty, in school-settings (Study 6, 9-11-year-olds, N=36; Study 7, 11-12-year-olds, N=150), and in a lab-based setting with undergraduate students (Study 8, 18-31-year-olds, N=38). We found that repeatedly reflecting on displays of moral beauty over an extended period of time, increased feelings of moral elevation in 11-12-year-olds and undergraduate students, but not children aged 9-11 years old. Chapter 6 provides an integrative discussion of the findings, theoretical and practical implications and avenues for future research.
Elasticity Management for Capacity Planning in Software as a Service Cloud Computing
Creators: name: Stauffer, Jon M.
name: Megahed, Aly
name: Sriskandarajah, Chelliah
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Medicine
subject: Ecology
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: Computational Biology

description: Applications of cloud computing are increasing as companies shift from on-premise IT environments to public, private, or hybrid clouds. Consequently, cloud providers use capacity planning to maintain the capacity of computing resources (instances) required to meet the dynamic nature of computing demand (queries). However, there is a trade-off between deploying too many costly instances, and deploying too few instances and paying penalties for not being able to process queries on-time. An instance has multiple resource dimensions and executing a query consumes multiple dimensions of an instance’s capacity. This detailed multi-dimensional management of cloud computing resource capacity is known as elasticity management and is an important issue faced by all cloud providers. Determining the optimal number of instances needed in a given planning horizon is challenging due to the combinatorial nature of the optimization problem involved. We develop an optimization model and related algorithms to capture the trade-off between the resource cost versus the delayed execution penalty in software as a service applications from the cloud provider’s perspective. We develop an exact approach to solve small-medium sized applications and heuristics to solve large applications. We then evaluate their performance via extensive computational analysis with real-world data and current cloud provider approaches. We also develop a stochastic framework and methodology to deal with demand uncertainty, and using two different randomly generated data sets (representing problem instances in practice), we demonstrate that robust solutions can be obtained.
A Universal Hurricane Frequency Function
Creators: name: Ehrlich, Robert
Publisher: name: arXiv
Year: 2010
Subjects: subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: Evidence is provided that the global distribution of tropical hurricanes is principally determined by a universal function H of a single variable z that in turn is expressible in terms of the local sea surface temperature and latitude. The data-driven model presented here carries stark implications for the large increased numbers of hurricanes which it predicts for a warmer world. Moreover, the rise in recent decades in the numbers of hurricanes in the Atlantic, but not the Pacific basin, is shown to have a simple explanation in terms of the specific form of H(z), which yields larger percentage increases when a fixed increase in sea surface temperature occurs at higher latitudes and lower temperatures.
description: In press with "Advances in Meteorology"
Wahrheit und Wandlung im Wesen im Wesen der dramatischen Gestalten Franz Grillparzers
Creators: name: Williams, Uta Barbara
Publisher: name: University of British Columbia
Year: 2011

description: Die folgende Interpretation versucht, die Entwicklung und damit die innere Wandlung der dramatischen Gestalten Grillparzers von ihrer ursprünglichen Wesenswahrheit zur Täuschung, die zugleich Selbsttäuschung und Betrug anderer ist, zu verfolgen, zu analysieren und zu motivieren. Zugrunde liegt dieser Analyse der Gedanke, dass Grillparzer den Menschen als ein notwendig transzendierendes, schrankenlos hochstre-bendes Wesen erfasst, dem es unmöglich ist, gesetzte Grenzen anzuerkennen und sich ihnen demütig zu unterwerfen. Als anschauliches Gleichnis hierfür zieht der Dramatiker den biblischen Sündenfall heran, als dort erstmalig die satanische Schlange im paradiesischen Menschen den phanta-sievollen Wunsch und das eigenwillige Streben erweckt, sein ursprüngliches, ihm von seinem Schöpfer gegebenes Wesen und mit ihm sein Geschick zu wandeln, urn so über sich selbst hinauszuwachsen: als Mensch war er geschaffen, doch wie Gott wollte er nun sein. - Als erbschuldiger "stolzer Enkel" ist es die Tragik eines jeden Menschen seitdem, dem "gleichen, ungezähmten Trieb," diesem eigensinnigen Selbstüberhebungsstreben seiner schuldigen Vorfahren zwangsläufig zu verfalien, wodurch ihm der kindlich naive, paradiesische Zustand seiner Wesenswahrheit und damit wiederum seiner Unschuld und Reinheit, seines inneren Eriedens und seiner eigentlichen Willensfreiheit verloren geht. Die einfachen, doch ehrgeizigen "Erdenbürger" drangen hinauf in den anderen, höheren Existenzbereich des still kontemplativen Seins der Künstler, Priester und Herrscher; ihr erstrebtes Ziel ist Glanz und Grösse, Ruhm und Ehre, Macht und Geltung. Die übernatürlichen, aussergewohnlichen Einzelnen hingegen sehnen sich hinunter in die Welt des "irdisch niedren Tuns." Einmal notwendigerweise aus dem heimatlichen, ursprünglichen Bereich seiner individuellen wahren Existenz herausgetreten und in der Wesensfremde erbärmlich gescheitert, bleibt dem übermütig hinausstrebenden, unglucklichen Menschen nur die einsichtsvolle, demütige, innere Umkehr, urn so in Wesenswahrheit "des Innern stillen Prieden" wiederzufinden. Diese Möglichkeit des Selbstgewinnes erblickt Grillparzer jedoch nicht im kampflosen Zurücksihken des Menschen in seinen ursprünglichen Stand der paradiesischen Wahrheit und Unschuld, noch durch einen göttlichen Akt der Gnade im neu-testamentarischen Sinne; sie stellt sich vielmehr dar als schwer errungene Selbstüberwindung. Diese Entsagung des persönlichen Verlangens nach den jenseits der gegebenen Grenzen lockenden Lebensgütern der "anderen Welt" ist an sich tragisch, da es dem transzendierenden, grenzenlos strebenden menschlichen Wesen widerspricht. [ … ]
Laser oscillation in a strongly coupled single quantum dot-nanocavity system
Creators: name: Nomura, M.
name: Kumagai, N.
name: Iwamoto, S.
name: Ota, Y.
name: Arakawa, Y.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: Strong coupling of photons and materials in semiconductor nanocavity systems has been investigated because of its potentials in quantum information processing and related applications, and has been testbeds for cavity quantum electrodynamics (QED). Interesting phenomena such as coherent exchange of a single quantum between a single quantum dot and an optical cavity, called vacuum Rabi oscillation, and highly efficient cavity QED lasers have been reported thus far. The coexistence of vacuum Rabi oscillation and laser oscillation appears to be contradictory in nature, because the fragile reversible process may not survive in laser oscillation. However, recently, it has been theoretically predicted that the strong-coupling effect could be sustained in laser oscillation in properly designed semiconductor systems. Nevertheless, the experimental realization of this phenomenon has remained difficult since the first demonstration of the strong-coupling, because an extremely high cavity quality factor and strong light-matter coupling are both required for this purpose. Here, we demonstrate the onset of laser oscillation in the strong-coupling regime in a single quantum dot (SQD)-cavity system. A high-quality semiconductor optical nanocavity and strong SQD-field coupling enabled to the onset of lasing while maintaining the fragile coherent exchange of quanta between the SQD and the cavity. In addition to the interesting physical features, this device is seen as a prototype of an ultimate solid state light source with an SQD gain, which operates at ultra-low power, with expected applications in future nanophotonic integrated systems and monolithic quantum information devices.
description: 12 pages, 4 figures