cssi/SciSciGPT-SciSciNet huggingface dataset:
Estimation of Origin and Destination Information from Bluetooth and Wi-Fi Sensing for Transit

Public urban transit offers a convenient, affordable, and sustainable mode of transportation for many. However, limited subsidies and revenue collected from bus fares place restrictions on the number of bus lines that can operate; these restrictions in turn limit the number of individuals who can benefit from public transit. To make well-informed operational decisions for transit planning and operations, understanding the origin and destination patterns of riders is crucial. However, traditional methods of transit data collection are labor-intensive and costly. Although some transit agencies use data from smart card transactions to obtain trip origin information readily, the trip destination information cannot be directly inferred. To aid in transit data acquisition efforts, this study presents a new technique that uses the Bluetooth and wireless fidelity (Wi-Fi) sensing technologies to estimate the origin and destination information for transit lines. Sensors were installed on four buses to collect Bluet...
In vitro CA-125 secretion by endometrium from women with advanced endometriosis.

Objective To determine if the endometrium of Women with endometriosis is a potential source of the elevated serum concentrations of CA-125 associated with endometriosis. Design Secretion of CA-125 by the endometrium in tissue culture was documented and measured in response to treatment with progesterone (P), 17 β -estradiol (E 2 ), and progesterone and estradiol (E 2 +P). Sequential biopsies of the endometrium from the early and late luteal phase were obtained from women with laparoscopically documented normal anatomy or moderate to severe endometriosis. Setting Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology at the University of Vermont, College of Medicine, Burlington, Vermont. Main Outcome Measures Secretion of CA-125 by endometrium in vitro was determined by radioimmunoassay in spent media using a commercially available kit (Centicor CA-125 Kit; Centicor, Malvern, PA). Results Secretion of CA-125 by endometrium in vitro is inhibited by the presence of P and E 2 +P in both the early and the late luteal phase. The amount of CA-125 secreted increases significantly from the early to the late luteal phase in all treatment groups. When compared with controls, the endometrium of women of with endometriosis secreted two to four times more CA-125 in all treatment groups, in both the early and late luteal phase. Conclusions When compared with control endometrium, the endometrium of women with advanced endometriosis secretes significantly more CA-125 and represents a potential source of the elevated serum levels of CA-125 seen in these women.
Design of Modified Amine Transfer Reagents Allows the Synthesis of α-Chiral Secondary Amines via CuH-Catalyzed Hydroamination.

The CuH-catalyzed hydroamination of alkenes and alkynes using a silane and an amine transfer reagent represents a simple strategy to access chiral amine products. We have recently reported methods to prepare chiral amines with high efficiency and stereoselectivity using this approach. However, the current technology is limited to the synthesis of trialkylamines from dialkylamine transfer reagents (R2NOBz). When monoalkylamine transfer reagents [RN(H)OBz] were used for the synthesis of chiral secondary amines, competitive, nonproductive consumption of these reagents by the CuH species resulted in poor yields. In this paper, we report the design of a modified type of amine transfer reagent that addresses this limitation. This effort has enabled us to develop a CuH-catalyzed synthesis of chiral secondary amines using a variety of amine coupling partners, including those derived from amino acid esters, carbohydrates, and steroids. Mechanistic investigations indicated that the modified amine transfer reagents ...
Scheduling for cloud-based computing systems to support soft real-time applications

Cloud-based computing infrastructure provides an efficient means to support real-time processing workloads, e.g., virtualized base station processing, and collaborative video conferencing. This paper addresses resource allocation for a computing system with multiple resources supporting heterogeneous soft real-time applications subject to Quality of Service (QoS) constraints on failures to meet processing deadlines. We develop a general outer bound on the feasible QoS region for non-clairvoyant resource allocation policies, and an inner bound for a natural class of policies based on dynamically prioritizing applications' tasks by favoring those with the largest (QoS) deficits. This provides an avenue to study the efficiency of two natural resource allocation policies: (1) priority-based greedy task scheduling for applications with variable workloads, and (2) priority-based task selection and optimal scheduling for applications with deterministic workloads. The near-optimality of these simple policies emerges when task processing deadlines are relatively large and/or when the number of compute resources is large. Analysis and simulations show substantial resource savings for such policies over reservation-based designs.
ShowMe the World: Learning with Global Peers

ShowMe The World, the global education project implemented by the University of Missouri-Columbia's College of Education (MU CoE), has created a global learning community using advanced technologies to develop and foster school/community relationships, promote cross-cultural learning and experience, and facilitate curricular change. Access to the Internet allows partner school participants to communicate through videoconferencing, digital resource exchange, and e-mail. This paper describes the project, and how it has fostered global partnerships.
Mathematics of Complete-Mixing Activated Sludge

Mathematical equations are presented to permit complete evaluation of 3 basic complete-mixing systems and examples given for each system to show how data obtained can be used in design of various systems. (34 refs.)
A nonparametric approach to identifying a subset of forecasters that outperforms the simple average

Empirical studies in the forecast combination literature have shown that it is notoriously difficult to improve upon the simple average despite the availability of optimal combination weights. In particular, historical performance-based combination approaches do not select forecasters that improve upon the simple average going forward. This paper shows that this is due to the high correlation among forecasters, which only by chance causes some individuals to have lower root-mean-squared error (RMSE) than the simple average. We introduce a new nonparametric approach to eliminate forecasters who perform well based on chance as well as poor performers. This leaves a subset of forecasters with better performance in subsequent periods. The average of this group improves upon the simple average in the SPF particularly for bond yields where some forecasters may be more likely to have superior forecasting ability.
Income Inequality and Economic Growth: Evidence from American Data

While most cross-country studies find a negative relationship between income inequality and economic growth, studies that use panel data suggest the presence of a positive relationship between inequality and growth. This paper uses a cross-state panel for the United States to assess the relationship between inequality and growth. Using both standard fixed effects and GMM estimations, this paper does not find evidence of a positive relationship between inequality and growth but finds some evidence in support of a negative relationship between inequality and growth. The paper, however, shows that the relationship between inequality and growth is not robust and that small differences in the method used to measure inequality can result in large differences in the estimated relationship between inequality and growth.
The Role of Evolutionary Selection in the Dynamics of Protein Structure Evolution

Homology modeling is a powerful tool for predicting a protein's structure. This approach is successful because proteins whose sequences are only 30% identical still adopt the same structure, while structure similarity rapidly deteriorates beyond the 30% threshold. By studying the divergence of protein structure as sequence evolves in real proteins and in evolutionary simulations, we show that this nonlinear sequence-structure relationship emerges as a result of selection for protein folding stability in divergent evolution. Fitness constraints prevent the emergence of unstable protein evolutionary intermediates, thereby enforcing evolutionary paths that preserve protein structure despite broad sequence divergence. However, on longer timescales, evolution is punctuated by rare events where the fitness barriers obstructing structure evolution are overcome and discovery of new structures occurs. We outline biophysical and evolutionary rationale for broad variation in protein family sizes, prevalence of compact structures among ancient proteins, and more rapid structure evolution of proteins with lower packing density.
Using 300 Pretreatment Shock Waves in a Voltage Ramping Protocol Can Significantly Reduce Tissue Injury During Extracorporeal Shock Wave Lithotripsy.

Abstract Purpose: Pretreating a pig kidney with 500 low-energy shock waves (SWs) before delivering a clinical dose of SWs (2000 SWs, 24 kV, 120 SWs/min) has been shown to significantly reduce the size of the hemorrhagic lesion produced in that treated kidney, compared with a protocol without pretreatment. However, since the time available for patient care is limited, we wanted to determine if fewer pretreatment SWs could be used in this protocol. As such, we tested if pretreating with 300 SWs can initiate the same reduction in renal lesion size as has been observed with 500 SWs. Materials and Methods: Fifteen female farm pigs were placed in an unmodified Dornier HM-3 lithotripter, where the left kidney of each animal was targeted for lithotripsy treatment. The kidneys received 300 SWs at 12 kV (120 SWs/min) followed immediately by 2000 SWs at 24 kV (120 SWs/min) focused on the lower pole. These kidneys were compared with kidneys given a clinical dose of SWs with 500 SW pretreatment, and without pretreatme...
Leucine metabolism in perfused rat skeletal muscle during contractions.

An isolated single rat hindlimb muscle preparation was used to examine leucine metabolism during steady-state conditions as a function of metabolic rate (VO2) and leucine concentration. The rates of muscle leucine uptake and leucine oxidation (measured as alpha-decarboxylation) were dependent on leucine delivery. At a physiological leucine concentration (0.1 mM), leucine uptake and alpha-ketoisocaproic acid (KIC) release during rest was 12.8 +/- 0.4 and 1.86 +/- 0.06 nmol.min-1.g-1 g, respectively. Leucine oxidation was 2.35 +/- 0.11 nmol.min-1.g-1 (n = 24) and if fully oxidized could account for only 3-4% of the resting VO2. This fraction was reduced to approximately 1% during contractions. The rate of leucine oxidation progressively increased, up to two to three times above rest (6-7 nmol.min-1.g-1), during contractions of graded frequency (7.5, 15, 30, 45, and 60 tetani/min) in a manner related to the eightfold increase in VO2 of the mixed fiber muscle. The fraction of muscle leucine uptake that was transaminated (i.e., leucine decarboxylation + KIC release) increased from 33% at rest to approximately 60% during contractions. The increase in leucine oxidation during contractions was probably primarily due to the high oxidative fast-twitch, red muscle mass, whose VO2 was estimated to increase up to 24-fold above rest. On the basis of our observed rates of muscle leucine alpha-decarboxylation, it is reasonable to attribute the rates of whole-body leucine oxidation of nontrained individuals during exercise to leucine oxidation by the working muscle.
SNAP: A General-Purpose Network Analysis and Graph-Mining Library

Large networks are becoming a widely used abstraction for studying complex systems in a broad set of disciplines, ranging from social-network analysis to molecular biology and neuroscience. Despite an increasing need to analyze and manipulate large networks, only a limited number of tools are available for this task. Here, we describe the Stanford Network Analysis Platform (SNAP), a general-purpose, high-performance system that provides easy-to-use, high-level operations for analysis and manipulation of large networks. We present SNAP functionality, describe its implementational details, and give performance benchmarks. SNAP has been developed for single big-memory machines, and it balances the trade-off between maximum performance, compact in-memory graph representation, and the ability to handle dynamic graphs in which nodes and edges are being added or removed over time. SNAP can process massive networks with hundreds of millions of nodes and billions of edges. SNAP offers over 140 different graph algorithms that can efficiently manipulate large graphs, calculate structural properties, generate regular and random graphs, and handle attributes and metadata on nodes and edges. Besides being able to handle large graphs, an additional strength of SNAP is that networks and their attributes are fully dynamic; they can be modified during the computation at low cost. SNAP is provided as an open-source library in C++ as well as a module in Python. We also describe the Stanford Large Network Dataset, a set of social and information real-world networks and datasets, which we make publicly available. The collection is a complementary resource to our SNAP software and is widely used for development and benchmarking of graph analytics algorithms.
Micro-Cathode Arc Thruster for small satellite propulsion

The George Washington University (GWU) has developed a CubeSat-class thruster called the Micro-Cathode Arc Thruster (μ CAT). The μCAT is a high Isp (2000–3500s), solid metal fueled, low average power (<0.1 W when operating) micro-thruster of small cross section (5 mm), with a mass of less than 200g, and no pressurant tanks. Electric current forms a plasma discharge between a concentric cathode-anode configuration. Thrust is produced through arc discharge, eroding some of the cathode material in uniform manner, to exit at high velocity, during which it is accelerated out the nozzle by a Lorentz force. Thrust can be controlled by varying the frequency of pulses, with a demonstrated range to date of 1–50 Hz, (1 μN–0.05 mN). The μ CAT design achieves uniform electrode erosion, and has demonstrated over two months of continuous operation during trials. The system operates at low voltage, accepting unregulated DC power from the spacecraft bus. The corresponding exhaust plume is 99% percent ionized, with near zero backflux. New ideas for high thrust-to power ratio microthruster will be discussed.
Student–Teacher Relationships for Young Children with Autism Spectrum Disorder: Risk and Protective Factors

The quality of early student-teacher relationships (STRs) has been shown to predict children's school adjustment, and children with autism spectrum disorder (ASD) are at risk for poor quality STRs. The present study examined 162 children with ASD (ages 4-7) and their teachers to evaluate student, teacher, and classroom characteristics that predicted concurrent and prospective STR quality across one school year. Child oppositional behavior, autism severity and teacher degree predicted changes in student-teacher conflict over a 1-year period, while child social skills and IQ positively predicted change in student-teacher closeness. Teacher preparedness, trainings in ASD, and classroom setting were unrelated to STR quality. Implications for intervention are discussed.
Predictors of NCLEX-RN success of associate degree graduates: A correlational study

Background/Significance: Enrich the literature on variables that predict first-time NCLEX-RN success. Among ADN students, what is the relationship between academic variables (cumulative GPA, TEAS test score, ATI test score, and final course grade for the last medical-surgical course) and successful first-time passing of the NCLEX-RN? H: ADN students who achieve high cumulative GPA (≥3.0), TEAS, ATI test scores and final course grade for the last med-surg course (≥80%) will pass the NCLEX-RN on their first attempt.
Membraneless flow battery leveraging flow-through heterogeneous porous media for improved power density and reduced crossover

We propose and demonstrate a novel flow battery architecture that replaces traditional ion-exchange membranes with less expensive heterogeneous flow-through porous media. Compared to previous membraneless systems, our prototype exhibits significantly improved power density (0.925 W cm−2), maximum current density (3 A cm−2), and reactant crossover, shown by the proposed experimentally-validated crossover model.
Path integral approach to the Wigner representation of canonical density operators for discrete systems coupled to harmonic baths.

We derive a semi-analytical form for the Wigner transform for the canonical density operator of a discrete system coupled to a harmonic bath based on the path integral expansion of the Boltzmann factor. The introduction of this simple and controllable approach allows for the exact rendering of the canonical distribution and permits systematic convergence of static properties with respect to the number of path integral steps. In addition, the expressions derived here provide an exact and facile interface with quasi- and semi-classical dynamical methods, which enables the direct calculation of equilibrium time correlation functions within a wide array of approaches. We demonstrate that the present method represents a practical path for the calculation of thermodynamic data for the spin-boson and related systems. We illustrate the power of the present approach by detailing the improvement of the quality of Ehrenfest theory for the correlation function Czz(t)=Re⟨σz(0)σz(t)⟩ for the spin-boson model with syste...
Circuit quantum electrodynamics architecture for gate-defined quantum dots in silicon

We demonstrate a hybrid device architecture where the charge states in a double quantum dot (DQD) formed in a Si/SiGe heterostructure are read out using an on-chip superconducting microwave cavity. A quality factor Q = 5400 is achieved by selectively etching away regions of the quantum well and by reducing photon losses through low-pass filtering of the gate bias lines. Homodyne measurements of the cavity transmission reveal DQD charge stability diagrams and a charge-cavity coupling rate g c / 2 π = 23 MHz. These measurements indicate that electrons trapped in a Si DQD can be effectively coupled to microwave photons, potentially enabling coherent electron-photon interactions in silicon.
Access control in ad hoc groups

Ad hoc groups, such as peer-to-peer (P2P) systems and mobile ad hoc networks (MANETs) represent recent technological advancements. They support low-cost, scalable and fault-tolerant computing and communication. Since such groups do not require any pre-deployed infrastructure or any trusted centralized authority they have many valuable applications in military and commercial settings as well as in emergency and rescue operations. However, due to lack of centralized control, ad hoc groups are inherently insecure and vulnerable to attacks from both within and outside the group. Decentralized access control is the fundamental security service for ad hoc groups. It is needed not only to prevent unauthorized nodes from becoming members but also to bootstrap other security services such as key management. In this paper, we survey a number of practical distributed access control mechanisms based on various flavors of threshold signatures.
Huddler: Convening Stable and Familiar Crowd Teams Despite Unpredictable Availability

Distributed, parallel crowd workers can accomplish simple tasks through workflows, but teams of collaborating crowd workers are necessary for complex goals. Unfortunately, a fundamental condition for effective teams -- familiarity with other members -- stands in contrast to crowd work's flexible, on-demand nature. We enable effective crowd teams with Huddler, a system for workers to assemble familiar teams even under unpredictable availability and strict time constraints. Huddler utilizes a dynamic programming algorithm to optimize for highly familiar teammates when individual availability is unknown. We first present a field experiment that demonstrates the value of familiarity for crowd teams: familiar crowd teams doubled the performance of ad-hoc (unfamiliar) teams on a collaborative task. We then report a two-week field deployment wherein Huddler enabled crowd workers to convene highly familiar teams in 18 minutes on average. This research advances the goal of supporting long-term, team-based collaborations without sacrificing the flexibility of crowd work.
CONTEMPORARY CROSSLINKED POLYMERS: ALL OUR BURDENS NOW OVER?

Highly crosslinked polyethylene (XLPE) was introduced to decrease peri-prosthetic osteolysis related to polyethylene wear, a major reason for revision of total hip arthroplasty. There are few reports of wear and osteolysis at 10 years post-operatively. We asked the following questions: (1) What are the linear and volumetric wear rates of one remelted XLPE at 10–14 years using the Martell method? (2) What is the relationship between volumetric wear, femoral head size, and osteolysis? (3) What is the incidence of osteolysis using conventional radiographs with Judet views and the Martell method? Methods We evaluated a previously reported cohort of 84 hips (72 patients) with one design of an uncemented acetabular component and one electron-beam irradiated, remelted XLPE at a mean follow-up of 11 years (range 10 to 14 years). Measurements of linear and volumetric wear were performed in one experienced laboratory by the Martell method and standard radiographs, with additional Judet views, were used to detect peri-prosthetic osteolysis. Statistical analysis of wear and osteolysis compared to head size was performed. Results The mean linear wear rate by the first-to-last method was 0.024 mm/year (median, 0.010 mm/year) and the mean volumetric wear rate by this method was 12.2 mm 3 /year (median, 3.6 mm 3 /year). We found no association between femoral head size and linear wear rate. However, there was a significant relationship between femoral head size and volumetric wear rates, with 36/40 mm femoral heads having significantly higher volumetric wear (p=0.02). Small osteolytic lesions were noted in 12 hips (14%), but there was no association with head size, acetabular component position, or linear or volumetric wear rates. Conclusion This uncemented acetabular component and this particular remelted XLPE had low rates of linear and volumetric wear. Small osteolytic lesions were noted at 10 to 14 years, but were not related to femoral head size, linear or volumetric wear rates.
Reduction of mutual coupling between strip dipole antennas at terahertz frequencies with an elliptically shaped graphene monolayer

In this paper, we propose to use the concept of mantle cloaking in order to decrease the mutual coupling between strip dipole antennas at low-terahertz frequencies. Here, we show that by wrapping the antennas with a properly tuned elliptically shaped graphene monolayer, the electromagnetic interaction between the antennas can be suppressed considerably, and the radiation patterns can be restored. The tunability of graphene with respect to its chemical potential allows us to reduce the mutual coupling between the antennas over a range of frequencies.
Hyperbolic periodic orbits in nongradient systems and small-noise-induced metastable transitions

Abstract Small noise can induce rare transitions between metastable states, which can be characterized by Maximum Likelihood Paths (MLPs). Nongradient systems contrast gradient systems in that MLP does not have to cross the separatrix at a saddle point, but instead possibly at a point on a hyperbolic periodic orbit. A numerical approach for identifying such unstable periodic orbits is proposed based on String method. In a special class of nongradient systems (‘orthogonal-type’), there are provably local MLPs that cross such saddle point or hyperbolic periodic orbit, and the separatrix crossing location determines the associated local maximum of transition rate. In general cases, however, the separatrix crossing may not determine a unique local maximum of the rate, as we numerically observed a counter-example in a sheared 2D-space Allen–Cahn SPDE. It is a reasonable conjecture that there are always local MLPs associated with each attractor on the separatrix, such as saddle point or hyperbolic periodic orbit; our numerical experiments did not disprove so.
The Impurity‐Drag Effect in Grain Boundary Motion

Abstract The drag on a grain boundary produced by an impurity atmosphere is examined in detail, and is found to depend on the velocity of the grain boundary relative to the diffusivity of the impurity and its interaction with the grain boundary. At high velocities the faster diffusing impurities have the greater drag; whereas at low velocities the reverse is true. With increasing impurity concentration or with decreasing temperature a boundary may experience a transition due to a changing interaction with its impurity atmosphere. The nature of the transition depends on driving force and may give rise to a large apparent activation energy, as well as jerky boundary motion due to the existence of a range of conditions where two boundary velocities are possible. Special orientation effects that may result in textures are expected to occur more easily at high velocities.
A neural network model to classify liver cancer patients using data expansion and compression

We develop a neural network model to classify liver cancer patients into high-risk and low-risk groups using genomic data. Our approach provides a novel technique to classify big data sets using neural network models. We preprocess the data before training the neural network models. We first expand the data using wavelet analysis. We then compress the wavelet coefficients by mapping them onto a new scaled orthonormal coordinate system. Then the data is used to train a neural network model that enables us to classify cancer patients into two different classes of high-risk and low-risk patients. We use the leave-one-out approach to build a neural network model. This neural network model enables us to classify a patient using genomic data without any information about the survival time of the patient. The results from genomic data analysis are compared with survival time analysis. It is shown that the expansion and compression of data using wavelet analysis and singular value decomposition (SVD) is essential to train the neural network model.
Comprehension and Writing Strategy Training Improves Performance on Content-Specific Source-Based Writing Tasks

Source-based essays are evaluated both on the quality of the writing and the content appropriate interpretation and use of source material. Hence, composing a high-quality source-based essay (an essay written based on source material) relies on skills related to both reading (the sources) and writing (the essay) skills. As such, source-based writing must involve language comprehension and production processes. The purpose of the current study is to examine the impact of reading, writing, and blended (i.e., reading and writing) strategy training on students’ performance on a content-specific source-based essay writing task. In contrast to general source-based writing tasks, content-specific source-based writing tasks are tasks wherein writers are provided the source material on which to base their essays. Undergraduate students (n = 175) were provided with strategy instruction and practice in the context of two intelligent tutoring systems, Writing Pal and Interactive Strategy Training for Active Reading and Thinking (iSTART). Results indicated that participants in the blended strategy training condition produced higher quality source-based essays than participants in the reading comprehension-only, writing-only, or control condition, with no differences observed between the latter three conditions. Further, the benefits of this blended strategy instruction remained significant regardless of prior reading and writing skills, or time on task.
Clinching auctions with online supply

Abstract Auctions for perishable goods such as Internet ad inventory need to make real-time allocation and pricing decisions as the supply of the good arrives in an online manner, without knowing the entire supply in advance. In this work, we consider a multi-unit model where buyers have global budget constraints, and the supply arrives in an online manner. Our main contribution is to show that for this setting there is an individually-rational, incentive-compatible and Pareto-optimal auction that allocates these units and calculates prices on the fly, without knowledge of the total supply. We do so by showing that the Adaptive Clinching Auction satisfies a supply-monotonicity property. Finally, while our main technical result concerns multi-unit supply, we propose a formal model of online supply that captures scenarios beyond multi-unit supply and has applications to sponsored search.
Calculation of temperature coefficients of reactivity for EBR-II kinetic analyses

Abstract Component and regional temperature coefficients of reactivity for four loading configurations of the Experimental Breeder Reactor-II (EBR-II) are compared. The coefficients are calculated by summations of microcoefficients obtained by fine axial delineations of every subassembly. A special-sum method for obtaining effective coefficients for use in kinetics code channels representing subassembly groupings is described. Evaluations of rod-bank suspension coefficients and of grid-plate radial-expansion coefficients are also presented.
HIGH-GAIN HARMONIC GENERATION OF SOFT X-RAYS WITH THE FRESH BUNCH TECHNIQUE

Abstract We report numerical simulations (using the TDA code) and analytical verification of the generation of 64 A high-power soft X-rays from an exponential regime single-pass seeded FEL. The seed is generated in the FEL using the High-Gain Harmonic Generation (HGHG) technique combined with the “fresh bunch” technique. A seed pulse at 2944 A is generated by conventional laser techniques. The seed pulse produces an intense energy modulation of the rear part of a 1 GeV, 1245 A electron beam in a “modulator” wiggler. In the “radiator” wiggler (resonant at 64 A), the energy modulation creates beam density modulation followed by radiation of the 46th harmonic of the seed. We use a magnetic delay to position the 64 A radiation at the undisturbed front of the bunch to serve as a seed for a single pass, exponential growth FEL. After a 9 m long exponential section followed by a 7 m long tapered section the radiation power reaches 3.3 GW.
Theory of nernst generators and refrigerators

Formulas for efficiency and coefficient of performance are derived for devices based on the Nernst and Ettingshausen effects. The equations reduce to those of Harman and Honig in the limits of small figure of merit and refrigerator current, but they do not approach the Carnot limits. To obtain a better device theory, one must solve a two‐dimensional partial differential equation in which the current density is allowed to vary with position.A crude maximization procedure for the figure of merit is shown for a one‐band nondegenerate semi‐conductor in a weak magnetic field. Experimental data indicate that HgxCd1−x Te alloys are perhaps the best materials for such devices at present.
From Status to Agency: Abolishing the “Very Spirit of Slavery”

In response to challenges that the disparate impact doctrine violates the Fourteenth Amendment’s Equal Protection Clause, the Thirteenth Amendment provides a constitutional foundation that deflects the equal protection argument. Early interpreters of the Thirteenth Amendment envisioned the provision as a means to abolish chattel as well as civil slavery, which was the condition of subordinate status shared by all Black persons. Resurrecting this interpretation of the Thirteenth Amendment reveals that early efforts to transform the status of Black persons failed as they unduly focused upon freedom of contract, rather than measures to achieve effective, individual agency. Interpreting the Thirteenth Amendment as a means of transitioning free Black persons from status to agency demonstrates that the societal barriers prohibiting the transformation warranted programs and policies beyond the right to contract. Based upon the dimensions of status suffered by Black persons—perceived as stigma, station, and stratification—the disparate impact doctrine is an appropriate Thirteenth Amendment vehicle to aid in transforming the subordinate status of Black persons.
Spatial variation of short-range order in amorphous intergranular complexions

Abstract Amorphous materials lack long-range order but short-range order can still persist through the recurrence of similar local packing motifs. While the short-range order in bulk amorphous phases has been well studied and identified as an intrinsic factor determining the material properties, these features have not been studied in disordered intergranular complexions. In this work, the short-range order in two types of amorphous complexions is studied with a Voronoi tessellation method. Amorphous complexions can have three distinct regions: amorphous-crystalline interfaces, regions deep inside the films that have short-range order identical to a bulk amorphous phase, and transition regions that connect the first two regions. However, thin amorphous films contain only the amorphous-crystalline interface and the transition region, providing further evidence of the constraints imposed by the abutting crystals. The thickness of the transition region depends on film thickness at low temperatures but becomes thickness-independent at high temperatures. Similarly, the complexion short-range order is dependent on the interfacing crystal plane at low temperatures, but this effect is lost at high temperatures. Our findings show that amorphous complexions contain spatial gradients in short-range order, meaning they are both structurally and chemically different from bulk metallic glasses.
The nanofluidic confinement apparatus: studying confinement-dependent nanoparticle behavior and diffusion

The behavior of nanoparticles under nanofluidic confinement depends strongly on their distance to the confining walls; however, a measurement in which the gap distance is varied is challenging. Here, we present a versatile setup for investigating the behavior of nanoparticles as a function of the gap distance, which is controlled to the nanometer. The setup is designed as an open system that operates with a small amount of dispersion of ≈20 μL, permits the use of coated and patterned samples and allows high-numerical-aperture microscopy access. Using the tool, we measure the vertical position (termed height) and the lateral diffusion of 60 nm, charged, Au nanospheres as a function of confinement between a glass surface and a polymer surface. Interferometric scattering detection provides an effective particle illumination time of less than 30 μs, which results in lateral and vertical position detection accuracy ≈10 nm for diffusing particles. We found the height of the particles to be consistently above that of the gap center, corresponding to a higher charge on the polymer substrate. In terms of diffusion, we found a strong monotonic decay of the diffusion constant with decreasing gap distance. This result cannot be explained by hydrodynamic effects, including the asymmetric vertical position of the particles in the gap. Instead we attribute it to an electroviscous effect. For strong confinement of less than 120 nm gap distance, we detect the onset of subdiffusion, which can be correlated to the motion of the particles along high-gap-distance paths.
Do interdisciplinary research teams deliver higher gains to science

The present paper takes its place in the stream of studies that analyze the effect of interdisciplinarity on the impact of research output. Unlike previous studies, in this study the interdisciplinarity of the publications is not inferred through their citing or cited references, but rather by identifying the authors' designated fields of research. For this we draw on the scientific classification of Italian academics, and their publications as indexed in the WoS over a 5-year period (2004---2008). We divide the publications in three subsets on the basis the nature of co-authorship: those papers coauthored with academics from different fields, which show high intensity of inter-field collaboration ("specific" collaboration, occurring in 110 pairings of fields); those papers coauthored with academics who are simply from different "non-specific" fields; and finally co-authorships within a single field. We then compare the citations of the papers and the impact factor of the publishing journals between the three subsets. The results show significant differences, generally in favor of the interdisciplinary authorships, in only one third (or slightly more) of the cases. The analysis provides the value of the median differences for each pair of publication subsets.
Long-Acting Reversible Contraception

Key Clinical PointsLong-Acting Reversible Contraception Intrauterine devices (IUDs) and hormonal implants are the most effective reversible methods of contraception — approximately 20 times as effective as pills, patches, and rings; couples should be counseled and informed about the superior effectiveness of long-acting reversible contraception (LARC) methods. IUDs and hormonal implants are safe for almost all women, including adolescents, as well as women in the postpartum or postabortion period. The main side effect of IUDs and hormonal implants is a change in bleeding patterns; anticipatory counseling about expected changes in bleeding may increase rates of continuation. Barriers to access to IUDs and hormonal implants remain, including those related to education, provider training, cost, and logistics; successful interventions have been shown to minimize these barriers. Adolescents and adult women should be counseled about contraception and should have access to the full range of contraceptive methods...
The relation among trapped cash, permanently reinvested earnings, and foreign cash ☆

Abstract We investigate the relation among trapped cash, permanently reinvested earnings, and foreign cash. We define trapped cash as cash and cash equivalents generated by foreign earnings and held by U.S. MNC's foreign subsidiaries due to concerns over repatriation taxes, and explain why trapped cash, permanently reinvested earnings, and foreign cash are not synonymous. We exploit the one-time tax rate reduction on repatriated earnings provided for under the American Jobs Creation Act of 2004 to construct a proxy to identify firms with trapped cash. We find R&D intensity, capital intensity, foreign growth opportunities and tax haven subsidiaries are significant indicators of trapped cash. Interestingly, we find firms with tax haven operations are less likely to have trapped cash. These findings highlight the joint role of tax havens as low-tax jurisdictions and offshore financial hubs. Finally, we investigate the relation between firm value and trapped cash. Controlling for excess cash, we find that trapped cash is negatively related to firm value, but primarily for firms with poor governance. Overall, results suggest that our measure is a parsimonious way to estimate the likelihood of having trapped cash that can be applied to a large sample of firms.
The effects of board gender diversity on a firm's risk strategies

We study whether board gender diversity (BGD) affects corporate risk strategies. Specifically, we investigate the association between BGD and firms’ reputation risk and financial risk. Using S&P data from 1997 to 2013, we find that BGD is negatively associated with tax avoidance, suggesting firms with gender-diverse boards are more cautious about potential reputation risks associated with aggressive tax strategies. However, we find that BGD is positively associated with firms’ financial risk. The combined findings illustrate that BGD aligns a firm's risk exposure closer to risk-neutral shareholders’ preferences by reducing reputation risk exposure while enabling necessary financial risk exposure.
Debt covenant design and creditor control rights: Evidence from the tightest covenant

Abstract Within the same debt contract, some financial covenants are considerably more restrictive than others. I exploit this heterogeneity in covenant design and show that the design of the most restrictive covenant is systematically associated with covenant outcomes - compliance, violations, or renegotiations. Consistent with an alleviation of moral hazard problems, tighter capital expenditure restrictions (performance covenants) are more likely to facilitate ex post creditor control through covenant renegotiations (violations). By contrast, borrowers are more likely to comply with contracts with tighter capital covenants, suggesting that these covenants more effectively align shareholder-creditor interests ex ante to avoid adverse selection problems.
Predicted Realization of Cubic Dirac Fermion in Quasi-One-Dimensional Transition-Metal Monochalcogenides

Cubically dispersed Dirac fermions are proposed exotic quasiparticles that have no analog in the standard model of particle physics, and they have not yet been identified in any compound. A design methodology quickly identifies one group of compounds as an ideal candidate and shows promise for realizing other novel types of fermions.
International Migration, Workers’ Remittances and Permanent Income Hypothesis

Summary Studies that examine the long-run impact of remittances on economic growth in West Africa and the Caribbean show that remittances are not growth enhancing. Money has been used toward consumption rather than investment. Because migrants from these regions are mostly permanent immigrants who settle in the host countries, we ask if there is a difference for South Asia where migrant workers are flooding for short-term, temporary contracts in the Middle Eastern countries. The permanent income hypothesis states that a permanent increase in income raises current consumption while transitory income increase is saved or smoothed over a life time. We argue that the transitory income remitted by short-term migrants is invested to generate future income when they return. We examine a panel data of five South Asian countries—Bangladesh, India, Nepal, Pakistan, and Sri-Lanka—for a period from 1975 to 2011. Using panel cointegration and Pooled Mean Group (PMG) estimation of dynamic heterogeneous panels, we show that there is a long-run significant impact of workers' remittances on income while the impact on consumption is not significant. A one-percent increase in remittance receipt per person raises per-capita income by approximately 0.23%. The results are robust across different tests.
How specialized is a diet specialist? Niche flexibility and local persistence through time of the Chisel-toothed kangaroo rat

ummary Rapid environmental changes are putting many species at risk, particularly niche specialists. In response, species can shift their ranges, or remain in place by taking advantage of new resources. The potential for specialists to undergo in situ niche shifts is not well understood yet can buffer species from the effects of long-term environmental change over centuries and millennia. In the Great Basin of western North America, the Chisel-toothed kangaroo rat, Dipodomys microps, is a folivore thought to be an obligate specialist on the desert shrub Atriplex confertifolia. Because of its association with A. confertifolia, D. microps is presumed to have tracked the shrub as it moved south during the last glacial maximum. However, recent phylogeographic evidence indicates that D. microps did not shift or contract its range into a southern refugium. Here we evaluate the role that niche flexibility may have played in allowing this presumed dietary specialist to cope with a changing environment and resource base. We do so using carbon and nitrogen isotopes measured in D. microps bone collagen from modern and fossil specimens spanning the last 8,000 years at Two Ledges Chamber (TLC) in northwestern Nevada. δ13C values indicates that, contrary to expectation, the population of D. microps at TLC consumes a variety of plants other than A. confertifolia, an isotopically distinct C4 shrub, and has done so for millennia. Mixing models suggest that the proportion of C4 in the diet was highest (˜35%) in the middle Holocene, and has declined towards the recent, especially over the last 30 years. δ15N values are consistently elevated through time suggesting that D. microps at TLC are potentially also consuming a high proportion of insects. Our results indicate that this population of dietary specialists has greater niche flexibility than previously assumed. This implies that, at the species level, even presumed niche specialists may be capable of undergoing niche shifts over centennial to millennial time scales in response to changing environmental conditions, and highlights the unique role that historical and paleontological data can play in establishing resource-use baselines of the past. This article is protected by copyright. All rights reserved.
Long-Run Pollution Exposure and Adult Mortality: Evidence from the Acid Rain Program

Abstract We estimate the effects of long-run pollution exposure on mortality by exploiting the United States Acid Rain Program (ARP) as a natural experiment. We use a difference-in-differences design to compare changes in adult mortality over time driven by installations of sulfur controls on power plants, combined with a model of atmospheric pollution transport. We find that sulfur controls reduced pollution immediately, with smaller relative improvements in the following years. Mortality reductions started small and grew steadily, suggesting cumulative health effects over time. We also find persistent mortality effects for those 35–64 years of age, suggesting the ARP had large productivity gains for the working-age population.
Testing the Stability and Reliability of U.S. Money Demand Functions

Abstract Our ability to model money demand in the postwar era has been constrained by evidence of instability in this function. Recent work has suggested that consumption, rather than income, is a more satisfactory measure of transactions demand. This paper attempts to provide a stable and reliable benchmark demand for money function, against which the consumption-based model may be measured. We find evidence against the claimed superiority of consumption-based functions.
Nondilated Obstructive Nephropathy

Three patients had renal failure due to obstructive nephropathy associated with processes that prevented dilatation of the collecting systems. Thus, various radiologic procedures, including renal sonography, angiography, and isotope renography, all failed to identify an obstructing process. Because of the high index of clinical suspicion, surgical exploration and nephrostomy were performed on each patient. This confirmed the presence of obstructive nephropathy and led to marked improvement of renal function in each case. When renal failure develops in a setting with a high probability of ureteral obstruction, this diagnosis should be vigorously pursued despite normal radiologic results.