Miracle-dz/UniFAR-FTUs huggingface dataset:
Platform Governance in the Presence of Within-Complementor Interdependencies: Evidence from the Rideshare Industry

Existing studies suggest that platform access restriction may cause restricted complementors to switch to competing platforms, which will increase complement quantity on competing platforms. We re-examine this prediction by accounting for the impact of economies of scope on complementor responses to platform access restriction. We argue that restricting a complementor’s access on a platform may prevent it from achieving economies of scope from multi-homing, thereby incentivizing it to abandon both the restricted and (unrestricted) competing platforms. Using rideshare data in New York City, we compare the numbers of trips made by Lyft and Uber drivers, respectively, before and after Lyft restricted drivers’ access on its platform. We find that Lyft’s access restriction reduced trip numbers not only on Lyft but also on Uber. In addition, both Lyft’s and Uber’s trip numbers decreased not only during the restricted low-demand periods (e.g., non-rush hours) but also during the unrestricted high-demand periods (e.g., rush hours). In contrast, after a substantial number of multi-homing drivers left both platforms following Lyft’s access restriction, a subsequent access restriction by Uber led to an increase in trip numbers on Lyft. These results highlight the importance of accounting for interdependencies across complementor activities when designing platform governance policies. This paper was accepted by Alfonso Gambardella, business strategy. Funding: H. D. Chung acknowledges support from the Strategic Research Foundation’s Dissertation Research [Grant SRF-2021-DRG-8363]. Supplemental Material: The data files and online appendix are available at https://doi.org/10.1287/mnsc.2023. 4706 .
Adversarial Collaborative Learning on Non-IID Features

Federated Learning (FL) has been a popular approach to enable collaborative learning on multiple parties without exchanging raw data. However, the model performance of FL may degrade a lot due to non-IID data. While many FL algorithms focus on non-IID labels, FL on non-IID features has largely been overlooked. Different from typical FL approaches, the paper proposes a new learning concept called ADCOL ( Ad versarial Co llaborative L earning) for non-IID features. Instead of adopting the widely used model-averaging scheme, ADCOL conducts training in an adversarial way: the server aims to train a discriminator to distinguish the representations of the parties, while the parties aim to generate a common representation distribution. Our experiments show that ADCOL achieves better performance than state-of-the-art FL algorithms on non-IID features.
On the minimal compactification of a polynomial in two variables

Consider a primitive polynomial $f$ in two variables, thought of as a map from the affine plane to the affine line. We study the minimimal compactification of $f$; from our result one deduces in particular that if one of the fibers of $f$ has only one fiber at infinity, then all the fibers of $f$ have a simultaneous resolution of singularities at infinity. From this one gets a very simple proof of the Suzuki-Abhyankar-Moh theorem on the embeddings of the affine line in the plane.
Boundary relations and boundary conditions for general (not necessarily definite) canonical systems with possibly unequal deficiency indices

We investigate in the paper general (not necessarily definite) canonical systems of differential equation in the framework of extension theory of symmetric linear relations. For this aim we first introduce the new notion of a boundary relation $\G:\gH^2\to\HH$ for $A^*$, where $\gH$ is a Hilbert space, $A$ is a symmetric linear relation in $\gH, \cH_0$ is a boundary Hilbert space and $\cH_1$ is a subspace in $\cH_0$. Unlike known concept of a boundary relation (boundary triplet) for $A^*$ our definition of $\G$ is applicable to relations $A$ with possibly unequal deficiency indices $n_\pm(A)$. Next we develop the known results on minimal and maximal relations induced by the general canonical system $ J y'(t)-B(t)y(t)=\D (t)f(t)$ on an interval $\cI=(a,b),\; -\infty\leq a<b\leq\infty $ and then by using a special (so called decomposing) boundary relation for $\Tma$ we describe in terms of boundary conditions proper extensions of $\Tmi$ in the case of the regular endpoint $a$ and arbitrary (possibly unequal) deficiency indices $n_\pm (\Tmi)$. If the system is definite, then decomposing boundary relation $\G$ turns into the decomposing boundary triplet $\Pi=\bt$ for $\Tma$. Using such a triplet we show that self-adjoint decomposing boundary conditions exist only for Hamiltonian systems; moreover, we describe all such conditions in the compact form. These results are generalizations of the known results by Rofe-Beketov on regular differential operators. We characterize also all maximal dissipative and accumulative separated boundary conditions, which exist for arbitrary (not necessarily Hamiltonian) definite canonical systems.
GDQFEM Numerical Simulations of Continuous Mediawith Cracks and Discontinuities

In the present paper the Generalized Differential Quadrature Finite Element Method (GDQFEM) is applied to deal with the static analysis of plane state structures with generic through the thickness material discontinuities and holes of various shapes. The GDQFEM numerical technique is an extension of the Generalized Differential Quadrature (GDQ) method and is based on the idea of conventional integral quadrature. In particular, the GDQFEM results in terms of stresses and displacements for classical and advanced plane stress problems with discontinuities are compared to the ones by the Cell Method (CM) and Finite Element Method (FEM). The multi-domain technique is implemented in a MATLAB code for solving irregular domains with holes and defects. In order to demonstrate the accuracy of the proposed methodology, several numerical examples of stress and displacement distributions are graphically shown and discussed.
Large-eddy simulation of turbulent flow using the finite element method

The equations of motion describing turbulent flows (in both the low and high Reynolds-number regimes) are well established. However, present day computers cannot meet the enormous computational requirement for numerically solving the governing equations for common engineering flows in the high Reynolds number turbulent regime. The characteristics that make turbulent, high Reynolds number flows difficult to simulate is the extreme range of time and space scales of motion. Most current engineering calculations are performed using semi-empirical equations, developed in terms of the flow mean (average) properties. These turbulence{open_quote} models{close_quote} (semi-empirical/analytical approximations) do not explicitly account for the eddy structures and thus, the temporal and spatial flow fluctuations are not resolved. In these averaging approaches, it is necessary to approximate all the turbulent structures using semi-empirical relations, and as a result, the turbulence models must be tailored for specific flow conditions and geometries with parameters obtained (usually) from physical experiments. The motivation for this research is the development of a finite element turbulence modeling approach which will ultimately be used to predict the wind flow around buildings. Accurate turbulence models of building flow are needed to predict the dispersion of airborne pollutants. The building flow turbulence models used today are not capable of predicting the three-dimensional separating and reattaching flows without the manipulation of many empirical parameters. These empirical parameters must be set by experimental data and they may vary unpredictably with building geometry, building orientation, and upstream flow conditions.
ABSORPTION EFFICIENCIES OF FORSTERITE. I. DISCRETE DIPOLE APPROXIMATION EXPLORATIONS IN GRAIN SHAPE AND SIZE

We compute the absorption efficiency (Qabs) of forsterite using the discrete dipole approximation in order to identify and describe what characteristics of crystal grain shape and size are important to the shape, peak location, and relative strength of spectral features in the 8–40 μm wavelength range. Using the DDSCAT code, we compute Qabs for non-spherical polyhedral grain shapes with aeff = 0.1 μm. The shape characteristics identified are (1) elongation/reduction along one of three crystallographic axes; (2) asymmetry, such that all three crystallographic axes are of different lengths; and (3) the presence of crystalline faces that are not parallel to a specific crystallographic axis, e.g., non-rectangular prisms and (di)pyramids. Elongation/reduction dominates the locations and shapes of spectral features near 10, 11, 16, 23.5, 27, and 33.5 μm, while asymmetry and tips are secondary shape effects. Increasing grain sizes (0.1–1.0 μm) shifts the 10 and 11 μm features systematically toward longer wavelengths and relative to the 11 μm feature increases the strengths and slightly broadens the longer wavelength features. Seven spectral shape classes are established for crystallographic a-, b-, and c-axes and include columnar and platelet shapes plus non-elongated or equant grain shapes. The spectral shape classes and the effects of grain size have practical application in identifying or excluding columnar, platelet, or equant forsterite grain shapes in astrophysical environs. Identification of the shape characteristics of forsterite from 8 to 40 μm spectra provides a potential means to probe the temperatures at which forsterite formed.
Horn's Curve Estimation Through Multi-Dimensional Interpolation

Abstract : A well-known multivariate data reduction method is principal components analysis (PCA). PCA transforms the variables under study into a set of components that are used to summarize the variation among the variables. The benefit is the dimension of the data may be reduced by the descriptive power of the components, permitting tractable analysis on large and messy datasets. Integral to successful PCA is determining when to stop extracting components - the matter is not a trivial one. A component extraction stopping rule that consistently produces reliable estimates of principal components is Horn's test. The drawback of the test is it requires a large amount of random data to evaluate the hidden component structure. Leveraging the flexibility and power of the MATLAB software package, a lookup table interpolates nearest neighbor searches of pre-processed mean eigenvalue data to provide real-time results for datasets up to 1,000 variables on 7,000 samples. The methodology is extended to a linear regression second-order model producing Horn's curve, significantly reducing the required size of the lookup table with no loss of resolution into the dimensionality estimate.
Near-infrared interferometry of eta Carinae with spectral resolutions of 1 500 and 12 000 using AMBER/VLTI

Aims. We present the first NIR spectro-interferometry of the LBV ? Carinae. The observations were performed with the AMBER instrument of the ESO Very Large Telescope Interferometer (VLTI) using baselines from 42 to 89 m. The aim of this work is to study the wavelength dependence of ? Car's optically thick wind region with a high spatial resolution of 5 mas (11 AU) and high spectral resolution. Methods: The observations were carried out with three 8.2 m Unit Telescopes in the K-band. The raw data are spectrally dispersed interferograms obtained with spectral resolutions of 1500 (MR-K mode) and 12 000 (HR-K mode). The MR-K observations were performed in the wavelength range around both the He I 2.059 ? m and the Br? 2.166 ? m emission lines, the HR-K observations only in the Br? line region. Results: The spectrally dispersed AMBER interferograms allow the investigation of the wavelength dependence of the visibility, differential phase, and closure phase of ? Car. In the K-band continuum, a diameter of 4.0±0.2 mas (Gaussian FWHM, fit range 28-89 m baseline length) was measured for ? Car's optically thick wind region. If we fit Hillier et al. (2001, ApJ, 553, 837) model visibilities to the observed AMBER visibilities, we obtain 50% encircled-energy diameters of 4.2, 6.5 and 9.6 mas in the 2.17 ? m continuum, the He I, and the Br? emission lines, respectively. In the continuum near the Br? line, an elongation along a position angle of 120°±15° was found, consistent with previous VINCI/VLTI measurements by van Boekel et al. (2003, A&A, 410, L37). We compare the measured visibilities with predictions of the radiative transfer model of Hillier et al. (2001), finding good agreement. Furthermore, we discuss the detectability of the hypothetical hot binary companion. For the interpretation of the non-zero differential and closure phases measured within the Br? line, we present a simple geometric model of an inclined, latitude-dependent wind zone. Our observations support theoretical models of anisotropic winds from fast-rotating, luminous hot stars with enhanced high-velocity mass loss near the polar regions. Based on observations collected at the European Southern Observatory, Paranal, Chile, within the AMBER guaranteed time programme 074.A-9025 and the VLTI science demonstration programme 074.A-9024.
Multi-Level Analysis of Complex IS Change: A Case Study of eCustoms

Although much efforts have been devoted to understanding IS change processes that take place in a single organization, there is very little understanding about the change processes that affect IS decisions and developments across organizations. In this paper we provide a conceptual framework to analyze and explain complex multi-level IS change. To demonstrate the use of the framework we apply it to analyze changes in the domain of eCustoms, as in this domain we find rich examples of multi-level IS changes. The framework combines the work on “motors of change” by Van de Ven and Poole with Pettigrew’s notions of “vertical” and “horizontal” levels of analysis. Based on our case analysis we conclude that the conceptual framework proves to be a useful lens through which to analyze complex multi-level IS change. We propose extensions of the framework by identifying different interaction types between the changes and we outline directions for further research. In this respect, this paper can be seen as a contribution to the existing IOS research on change.
On orders of finite groups and centralizers of $p$-elements

In this paper we shall see that a similar theorem holds when c is allowed to be I CG(x) I for any element x in G of order p. Indeed, consider the following two statements for a fixed prime p : (I) There exists a function f(c) with the following property: If G is a finite group of order divisible by p, x is an element of order p, c= \ CG(x) \ , and S(G) is the solvable radical of G, then | G: Oy, P(S(G)) \ <f(c). (II) There exists a function g(c) with the following property: If G is a finite non-abelian simple group, τ is an automrophism of order p of G, and *=|Cc(τ)|,then
Understanding Implementation Challenges of Cloud-based Enterprise Systems at Universities

Cloud-based enterprise systems (Cloud ES) are developing rapidly and their application has increased substantially. Early research suggested that tertiary educational institutions adopt Cloud ES due to benefits such as increased productivity and easy access to data. Although existing studies have identified some advantages, Cloud ES implementation is a complex initiative, and we do not yet have sufficient knowledge for successful implementation. This study identifies the challenges of Cloud ES implementation and investigates how the various stakeholders mitigated these challenges in an Australian university. A qualitative case study approach employing semi-structured interviews with the stakeholders was employed to explore the issues. The study shows the role of stakeholders in implementation and how they interacted with others to mitigate challenges. The results can serve as a foundation to develop guidelines for tertiary educational institutions who are considering implementing Cloud ES.
Competing magnetic ground states in nonsuperconducting Ba(Fe1-xCrx)2As2 as seen via neutron diffraction

We present neutron diffraction measurements on single-crystal samples of nonsuperconducting Ba(Fe{sub 1-x}Cr{sub x}){sub 2}As{sub 2} as a function of Cr doping for 0 {le} x {le} 0.47. The average spin-density-wave moment is independent of concentration for x {le} 0.2 and decreases rapidly for x {ge} 0.3. For concentrations in excess of 30% chromium, we find a new competing magnetic phase consistent with G-type antiferromagnetism which rapidly becomes the dominant magnetic ground state. Strong magnetism is observed for all concentrations measured, naturally explaining the absence of superconductivity in the Cr-doped materials.
Evidence of a nonadaptive buildup of mutational load in human populations over the past 40,000 years

The role played by natural selection in shaping present-day human populations has re-ceived extensive scrutiny [1, 2, 3], especially in the context of local adaptations [4]. However, most studies to date assume, either explicitly or not, that populations have been in their current locations long enough to adapt to local conditions [5], and that population sizes were large enough to allow for the action of selection [6]. If these conditions were satisﬁed, not only should selection be eﬀective at promoting local adaptations, but deleterious alleles should also be eliminated over time. To assess this prediction, the genomes of 2,062 individuals, including 1,179 ancient humans, were reanalyzed to reconstruct how frequencies of risk alleles and their homozygosity changed through space and time in Europe. While the overall deleterious homozygosity consistently decreased through space and time, risk alleles have shown a steady increase in frequency. Even the mutations that are predicted to be most deleterious fail to exhibit any signiﬁcant decrease in frequency. These conclusions do not deny the existence of local adaptations, but highlight the limi-tations imposed by drift and range expansions on the strength of selection in purging the mutational load aﬀecting human populations.
GENOMIC INVESTIGATIONS OF ACUTE HEPATITIS OF UNKNOWN AETIOLOGY IN CHILDREN

Since the first reports of hepatitis of unknown aetiology occurring in UK children, over 1000 cases have been reported worldwide, including 268 cases in the UK, with the majority younger than 6 years old. Using genomic, proteomic and immunohistochemical methods, we undertook extensive investigation of 28 cases and 136 control subjects. In five cases who underwent liver transplantation, we detected high levels of adeno-associated virus 2 (AAV2) in the explanted livers. AAV2 was also detected at high levels in blood from 10/11 non-transplanted cases. Low levels of Adenovirus (AdV) and Human Herpesvirus 6B (HHV-6B), both of which enable AAV2 lytic replication, were also found in the five explanted livers and blood from 15/17 and 6/9 respectively, of the 23 non-transplant cases tested. In contrast, AAV2 was detected at low titre in 6/100 whole bloods from child controls from cohorts with presence or absence of hepatitis and/or adenovirus infection. Our data show an association of AAV2 at high titre in blood or liver tissue, with unexplained hepatitis in children infected in the recent AdV-F41 outbreak. We were unable to find evidence by electron microscopy, immunohistochemistry or proteomics of AdV or AAV2 viral particles or proteins in explanted livers, suggesting that hepatic pathology is not due to direct lytic infection by either virus. The potential that AAV2, although not previously associated with disease, may, together with AdV-F41 and/or HHV6, be causally implicated in the outbreak of unexplained hepatitis, requires further investigation.
Ethnic disparities in medication adherence? A systematic review examining the association between ethnicity and antidiabetic medication adherence

Objectives Adherence to prescribed medication is an essential component of diabetes management to obtain optimal outcomes. Understanding the relationship between medication adherence and ethnicity is key in optimising treatment for all people with different chronic illnesses, including those with diabetes. The aim of this review is to examine whether the adherence to antidiabetic medications differed by ethnicity among people with diabetes. Methods A systematic review was conducted of studies reporting adherence to antidiabetic medication amongst people from different ethnic groups. MEDLINE, Embase, CINAHL, and PsycINFO were searched from their inception to June 2021 for quantitative studies with a specific focus on studies assessing adherence to antidiabetic medications (PROSPERO: CRD42021278392). The Joanna Briggs Institute critical appraisal checklist and a second checklist designed for studies using retrospective databases were used to assess study quality. A narrative synthesis approach was used to summarize the results based on the medication adherence measures. Results Of 15,685 citations screened, 39 studies that included observational retrospective database research and cross-sectional studies were selected, each of which involved diverse ethnic groups from different settings. This review identified a difference in the adherence to antidiabetic medications by ethnicity in 37 studies, despite adjustment for several confounding variables that may otherwise explain these differences. Conclusion This review revealed that adherence to antidiabetic medication differed by ethnicity. Further research is needed to explore the ethnicity-related factors that may provide an explanation for these disparities.
Gαs and Gαq/11 protein coupling bias of two AVPR2 mutants (R68W and V162A) that cause nephrogenic diabetes insipidus

Abstract Loss-of-function mutations of the arginine vasopressin receptor 2 gene (AVPR2) cause Nephrogenic diabetes insipidus (NDI). AVPR2 is a kind of G protein coupled receptor (GPCR) and mainly couples with Gαs protein leading to cAMP accumulation in the cell as a secondary messenger. Recent studies showed that some AVPR2 mutations could cause biased Gαq/11 protein coupling rather than Gαs. Investigation into the characterization of biased receptors may give insights into the relationship between the conformational change of the receptor because of the mutation and related downstream signaling. In this study, R68W and V162A were analyzed to whether they show a bias to Gαs or Gαq/11 proteins. Their functionality in terms of cAMP production via Gαs protein coupling was decreased compared to the wild-type receptor. On the other hand, they showed the ability to couple with Gαq/11 protein and make Ca2+ mobilization at different levels in the cell. R68W showed bias to coupling with Gαq/11 protein rather than V162A and wild-type receptor. Studies about the Gα protein coupling bias of mutant AVPR2s may broaden our understanding of the relationship between the changed conformation of the receptor and consequently activated signaling pathways, and also may shed light on the development of more effective new therapeutics.