nils-herrmann/clean_scirepeval huggingface dataset:
When does gradient descent with logistic loss find interpolating two-layer networks?

We study the training of finite-width two-layer smoothed ReLU networks for binary classification using the logistic loss. We show that gradient descent drives the training loss to zero if the initial loss is small enough. When the data satisfies certain cluster and separation conditions and the network is wide enough, we show that one step of gradient descent reduces the loss sufficiently that the first result applies. In contrast, all past analyses of fixed-width networks that we know do not guarantee that the training loss goes to zero.

Field of study: Computer science
The diffusion model for migration and selection in a dioecious population

The diffusion approximation is derived for migration and selection at a multiallelic locus in a dioecious population subdivided into a lattice of panmictic colonies. Generations are discrete and nonoverlapping; autosomal and X-linked loci are analyzed. The relation between juvenile and adult subpopulation numbers is very general and includes both soft and hard selection; the zygotic sex ratio is the same in every colony. All the results hold for both adult and juvenile migration. If ploidy-weighted average selection, drift, and diffusion coefficients are used, then the ploidy-weighted average allelic frequencies satisfy the corresponding partial differential equation for a monoecious population. The boundary conditions and the unidimensional transition conditions for coincident discontinuities in the carrying capacity and migration rate extend identically. The previous unidimensional formulation and analysis of symmetric, nearest-neighbor migration of a monoecious population across a geographical barrier is generalized to symmetric migration of arbitrary finite range, and the transition conditions are shown to hold for a dioecious population. Thus, the entire theory of clines and of the wave of advance of favorable alleles is applicable to dioecious populations.

Field of study: Biology, Mathematics
Cost of illness studies: An aid to decision-making?

(1986) 119–143 contained an article by Henke and Behrens which purported to estimate the economic costs of illness in the Federal Republic of Germany. The paper is one of the latest in a collection of empirical studies which are linked by a common approach and methodology dating from Rice's seminal work in 1966. It has been argued that such work is of value in indicating the burden of disease and in setting priorities in research, prevention and treatment. Indeed it has been claimed that cost of illness studies are an essential component of the evaluation of alternative demands on scarce health care resources. However, cost of illness estimates are based on unsound theory which leads to circularity and bias in their policy prescriptions. The shortcomings of the technique are both well known and well documented yet cost of illness estimates continue to be produced. In response to this we would like to restate the theoretical errors of the approach and indicate its limitations for policy. We would also like to remind policy-makers that economics can offer something more useful than a method for estimating the ‘benefits of the unattainable’. Cost-benefit analysis provides a framework in which information relevant to the decision at hand, on the effectiveness and resource consequences of policy options, can be considered in a systematic manner.

Field of study: Medicine, Political science
Molecular Rotors as Fluorescent Viscosity Sensors: Molecular Design, Polarity Sensitivity, Dipole Moments Changes, Screening Solvents, and Deactivation Channel of the Excited States

A library of new fluorescent molecular rotors (FMRs) for viscosity sensing was synthesized. The sensitivity of the fluorescence emission toward solvent viscosity and polarity was investigated by using UV/Vis absorption, fluorescence emission spectra, and theoretical calculations. For the new FMRs, red-shifted emissions at 620 nm, Stokes shifts of 170 nm, and up to 40-fold fluorescence enhancement upon increasing the viscosity of solvents were observed (cf. known FMRs with emissions at 491 nm, Stokes shift of 33 nm and fivefold emission enhancement). By using solvents with high viscosity but low polarity, for example, polyethylene glycol (PEG-400) or dimethyl silicone oil, rotors previously identified as non-FMRs with ethylene glycol/glycerol show FMR properties. We found triphenylamine (TPA)-based rotors showed solvent-polarity-dependent emission, but also FMR properties. This is contrary to the known theory of FMRs. One of the TPA-based rotors shows the highest x value of 0.88 (versus 0.6 for known FMRs). The emissive excited states of the FMRs proved to be locally excited (LE) states and twisted intramolecular charge-transfer (TICT) states were identified as dark states through trifluoroacetic acid titration and DFT/time-dependent DFT calculations, which show that the nonradiative decay channel of the excited FMRs is the rotation about the dicyanovinyl C=C double bonds in the S1 state, not rotation around C–C single bonds. Extension of the π conjugation of the rotors increases the rotation barrier around the C=C double bond in the S1 state (to ca. 50 kJ mol–1 or higher), thus the nonradiative channel is blocked and higher fluorescence quantum yields are observed for the new rotors. Our results will be useful for future design of FMRs as fluorescent viscosity sensors.

Field of study: Chemistry
Strategies Applied by the Board of Management to Enhance Students Academic Performance in National Examinations in Secondary Schools in Mandera County, Kenya

The thrust of the study was to examine the strategies applied by Board of Management to enhance students’ academic performance in National Examinations in secondary schools in Mandera County. The study was premised on the Goal Path Leadership Theory propounded by Martin Evans and Robert House (1970) which contends that people are satisfied by their work if they believe that their work will lead to things that are highly valued.  A descriptive survey research design was adopted. The study was conducted in all five public secondary schools in Mandera County of North Eastern Province. The study involved a survey design of the five secondary schools in the district. Purposive sampling technique was used to draw 5 principals and 30 members of the Board of Management in the selected schools to yield a sample size of 35 subjects to participate in the study. Focus group guideline for members of Board of Management was the main research instrument used to collect data.  The qualitative approach involving thematic analysis was used to manage data. The study established that most of the members of the Board of Management lacked requisite knowledge and skills to manage these institutions as a result of their low level of formal education. As a result, there were challenges including: lack of monitoring of most decisions made by the Board; frequent political interference especially from powerful politicians and members of the provincial administration; general school mismanagement; amongst others. These challenges impacted negatively on students’ academic performance in the study locale. It was recommended that members of the Board of Management should be appointed on merit and provided with appropriate managerial training; proper communication and monitoring of crucial decisions made by the Board ; and optimal utilization of available physical and human resources geared towards enhancing students academic performance in the study locale of Mandera County.( 305 words).  Managerial skill, Board of Management, Challenges, Secondary education, Academic Performance; Mandera County, Kenya

Field of study: Education
Low-Resolution Vehicle Image Recognition Technology by Frame-Composition of Moving Images

Developing on-board automotive driver assistance systems aiming to alert drivers about driving environments, and possible collision with other vehicles has attracted a lot of attention lately. Especially, many researchers have suggested the forward vehicle recognition technology by a camera on vehicle. In the forward vehicle recognition, however, it is difficult to detect the features of vehicle from a distant vehicle image by conventional methods because the image is too low-resolution (LR). This paper presents vehicle image recognition technology for detecting of the features of a distant vehicle by frame-composition of moving images. To detect the vehicle features of a distant LR vehicle image, we use the moving images obtained from the camera on the vehicle, and utilize super-resolution (SR) image reconstruction. SR image reconstruction is to use signal processing techniques to obtain a high-resolution (or sequence) image from observed multiple LR images. Use of this technique on real road image, we show the effectiveness of the proposed techniques.

Field of study: Computer science
Analysis of the low-energy ηNN-dynamics within a three-body formalism

The interaction of an η-meson with two nucleons is studied within a three-body approach. The major features of the ηNN-system in the low-energy region are accounted for by using a s-wave separable ansatz for the two-body ηN and NN amplitudes. The calculation is confined to the (Jπ;T) = (0-;1) and (1-;0) configurations which are assumed to be the most promising candidates for virtual or resonant ηNN-states. The eigenvalue three-body equation is continued analytically into the nonphysical sheets by contour deformation. The position of the poles of the three-body scattering matrix as a function of the ηN-interaction strength is investigated. The corresponding trajectory, starting on the physical sheet, moves around the ηNN three-body threshold and continues away from the physical area giving rise to virtual ηNN-states. The search for poles on the nonphysical sheets adjacent directly to the upper rim of the real energy axis gives a negative result. Thus no low-lying s-wave ηNN-resonances were found. The possible influence of virtual poles on the low-energy ηNN-scattering is discussed.

Field of study: Physics
Sampling expansions for discrete transforms and their relationship with interpolation series

Kramer's sampling theorem gives us the possibility to reconstruct integral transforms from their values at sequences of real numbers. It is known that this theorem includes the Whittaker-Shannon-Kotel'nikov (WSK) sampling theorem, and that many Kramer-type expansions can be written in forms of Lagrange-type interpolation series. Here we introduce a discrete version of Kramer's theorem and prove that the discrete theorem is equivalent to Kramer's theorem. The WSK sampling theorem is shown to be included in the new theorem. Moreover, the relationship between the sampling expansions of the discrete transforms and the interpolation expansions is discussed.

Field of study: Philosophy
Anomalous normal fluid response in a chiral superconductor UTe2

Chiral superconductors have been proposed as one pathway to realize Majorana normal fluid at its boundary. However, the long-sought 2D and 3D chiral superconductors with edge and surface Majorana normal fluid are yet to be conclusively found. Here, we report evidence for a chiral spin-triplet pairing state of UTe2 with surface normal fluid response. The microwave surface impedance of the UTe2 crystal was measured and converted to complex conductivity, which is sensitive to both normal and superfluid responses. The anomalous residual normal fluid conductivity supports the presence of a significant normal fluid response. The superfluid conductivity follows the temperature behavior predicted for an axial spin-triplet state, which is further narrowed down to a chiral spin-triplet state with evidence of broken time-reversal symmetry. Further analysis excludes trivial origins for the observed normal fluid response. Our findings suggest that UTe2 can be a new platform to study exotic topological excitations in higher dimension.

Field of study: Physics
Electric vehicle adoption: can short experiences lead to big change?

Plug-in electric vehicles (PEVs) offer a promising pathway to decarbonizing the personal transportation sector, but PEV sales remains low. Prior research has found that direct experience with PEVs increases consumers' stated purchase consideration, but these studies have used relatively long exposure times (days to months) with a PEV. To assess the effect of shorter exposure times (e.g. minutes) on stated purchase consideration, we conducted an experiment at the 2019 Washington D.C. Auto Show. Participants (n = 6,518) were asked to rate their level of consideration to adopt a PEV before and after riding in one of four different PEVs for just three to five minutes. We find that the experience of riding in a PEV on average had a significant, positive effect on participants' consideration ratings. We also find that the vast majority of respondents were unable to correctly answer basic knowledge questions about refueling a PEV and federal subsidies available for purchasing a PEV. These results suggest that while consumer knowledge about PEVs remains low, short rides or drives in a PEV could be an effective, more scalable strategy for increasing PEV consideration across larger populations.

Field of study: Environmental science
Chemical deposition of bismuth selenide thin films using N,N-dimethylselenourea

Good quality thin films of bismuth selenide of thickness up to were deposited from solutions containing bismuth nitrate, triethanolamine and N,N-dimethylselenourea maintained at temperatures ranging from room temperature to . X-ray diffraction patterns of the samples annealed at in air match the standard pattern of hexagonal (paraguanajuatite, JCPDS 33-0214). The films exhibit strong optical absorption corresponding to a bandgap of about 1.7 - 1.41 eV in the as-prepared films. These values decrease to about 1.57 - 1.06 eV upon annealing the films at for 1 h in nitrogen. As-deposited, the films show high sheet resistance in the dark. Annealing the films in air or in nitrogen enhances the dark current by about seven orders of magnitude; the resulting dark conductivity is about . This enhancement in conductivity results from improved crystallinity as well as from partial loss of selenium.

Field of study: Materials science
Poster - Thurs Eve-07: The dosimetric consequences of MLC position inaccuracy in IMRT.

The Multileaf Collimator (MLC), the most widely used means of intensity modulating beams for IMRT, is subject to random and systematic errors in leaf positions that may compromise the treatment quality. This work is a simulation study of the effect of random and systematic errors in leaf position on delivered dose distributions. The dosimetric effects of random errors of up to 2 mm and systematic errors (±1mm in 2 banks, ±0.5mm in 2 banks and 2mm in 1 bank of leaves) were analysed for a typical head and neck IMRT plan and a typical prostate IMRT plan. Dose Volume Histograms and Equivalent Uniform Doses (EUD) of the target volumes, bladder and rectum for the prostate plan and brainstem, larynx, parotids and spinal cord for the head and neck plan were calculated with and without MLC positioning errors and compared. The results show that if we adopt a 2% change in EUD of the target and 2 Gy for the OARs as acceptable levels of uncertainty in dose due to MLC effects only, then random errors of up to 2mm may be tolerated but systematic errors in leaf position will need to be limited to 0.5mm. Our study provides guidance, based on a surrogate of clinical outcome, for the development of quality control standards for multileaf collimators.

Field of study: Medicine, Physics
Mechanical Behavior Prediction of Asphalt Mastic Based on 2D Micro Finite Element Approach

Asphalt mastic is a kind of composite which included fine aggregates, asphalt and filler. Its mechanical behavior has significant effect on asphalt mixture. Therefore, mechanical behavior of asphalt mastic was predicted using FEM method. Stress concentration and effective modulus were evaluated. Result indicates that factor of stress concentration decrease with mastic modulus. Scale of FEM model has significant influence on effective modulus of mastic. The predicted modulus tends to a stable value when scale ratio is greater than 5.

Field of study: Engineering
Expression and characterization of the zeta 1 subunit of the N-methyl-D-aspartate (NMDA) receptor channel in a baculovirus system.

Using a baculovirus expression vector system, the zeta 1 subunit of the mouse N-methyl-D-aspartate (NMDA) receptor channel was expressed in Spodoptera frugiperda insect cells. The peptide corresponding to the C-terminus of the zeta 1 subunit was synthesized by using the multiple antigen peptide (MAP) system, and an antibody to the synthetic peptide was produced. Immunoblotting using the newly developed antibody revealed the major 122-kDa and the minor 104-kDa protein bands. The effect of tunicamycin on the immunoblots and [35S]methionine/[35S]cysteine metabolic radiolabeling suggested that the two bands corresponded to glycosylated and non-N-glycosylated forms, respectively. Membranes prepared from insect cells infected with the recombinant virus had the binding activity of antagonist ligand 5,7-[3-3H]dichlorokynurenate (DCKA) of a glycine recognition domain of the receptor. Both immunofluorescence labeling and the [3H]DCKA binding assays also showed a greater level of expression (Bmax = 51 pmol/mg protein) in the insect cells. The ligand binding characteristics of the receptors expressed in insect cells suggested that the single zeta 1 subunit protein has glycine antagonist binding properties comparable to those of the native NMDA receptor channels. The lack of DCKA-binding activity of the non-N-glycosylated NMDA receptor expressed in the presence of tunicamycin suggested that N-linked oligosaccharide is essentially required for expression of a functional receptor in insect cells. This is the first report describing the importance of N-glycosylation for the acquisition of ligand binding to NMDA receptor channel subunit protein.

Field of study: Biology
Armadillo: A Compilation Chain for Privacy Preserving Applications

In this work we present Armadillo a compilation chain used for compiling applications written in a high-level language (C++) to work on encrypted data. The back-end of the compilation chain is based on homomorphic encryption. The tool-chain further automatically handle a huge amount of parallelism so as to mitigate the performance overhead of using homomorphic encryption.

Field of study: Computer science, Mathematics
Libel: Its Purpose and Reform

Discussion of libel often fails to define defamation law's purpose and thus properly to assess its value. This article argues that defamation's purpose relates to fundamental human interests in sociality, directly linked to important aspects of human health and well‐being. Protecting such interests is arguably required by the right to private life under ECHR article 8 and should not count as a violation of the right to freedom of speech. Some current reform proposals are criticised as failing to appreciate the importance of protecting sociality. ‘Business’ libel, however, often protects not sociality but purely economic interests. The article therefore argues that the protection of libel law, as opposed to that offered by malicious falsehood and the economic torts, should be withdrawn from purely economic reputation, starting with removing the rights of corporations to sue in defamation, a position compatible with the ECtHR's decision in Karako v Hungary.

Field of study: Law
Paramedic ethics for computer professionals

Most computer professionals know that difficult ethical issues may arise in their work. We believe that these professionals want to “do the right thing.” They accept their responsibilities as moral agents and they recognize that their special technical skills give them power and responsibilities. However, the will to act ethically is not sufficient; computer professionals also need skills to arrive at reasonable, ethical decisions. In this article we suggest a set of guidelines to help computer professionals consider the ethical dimensions of technical decisions and offer practical advice to individuals who need to make timely decisions in an ethical manner. We call our guidelines a paramedic method to suggest a medical analogy. We use our method on two realistic ethical dilemmas facing computer professionals. We gather and analyze the data and reach conclusions much as the principals in our cases might. Our paramedic method is not a replacement for considered analysis by professional ethicists. It is a method by which computer professionals can quickly organize and view the facts of an ethical dilemma in a systematic and practical fashion.

Field of study: Computer science, Engineering
Path integration and lesions within the head direction cell circuit: comparison between the roles of the anterodorsal thalamus and dorsal tegmental nucleus.

Experiments were designed to determine whether 2 regions of the head direction cell circuit, the anterodorsal thalamic nucleus (ADN) and the dorsal tegmental nucleus (DTN), contribute to navigation. Rats were trained to perform a food-carrying task with and without blindfolds prior to receiving sham lesions or bilateral lesions of the ADN or DTN. ADN-lesioned rats were mildly impaired in both versions of the task. DTN-lesioned rats, however, were severely impaired and showed reduced heading accuracy in both task versions. These findings suggest that although both the DTN and ADN contribute to navigation based on path integration and landmarks, disruption of the head direction cell circuit at the level of the DTN has a significantly greater effect on spatial behavior than lesions of the ADN.

Field of study: Biology, Psychology
Status of the Milan Superconducting Cyclotron Project

This paper presents an updated status report on the Superconducting Cyclotron, under construction at the University of Milan during the past two years, with funding chiefly provided by the Italian National Institute for Nuclear Physics. The cyclotron is designed for a K of 800 and a K /SUB FOC/ of 200 and thus yields maximum energies of 100 MeV/n for fully stripped light ions and 20 MeV/n for uranium and other heavy ions. The pole radius is 90 cm with three sectors having an average spiral constant of 1/45.7 rad/cm. The average magnetic field will span between 22 and 48 K Gauss with a corresponding R.F. frequency range between 15 and 48 MHz. The anticipated peak dee voltage is 100 KV with harmonic operation from h = 1 to h = 4. The operating modes include the use of an internal PIG source, injection from a 16 MV tandem, and axial injection from an external ion source. This paper presents the design parameters and outlines the progress made so far.

Field of study: Physics