cssi/SciSciGPT-SciSciNet huggingface dataset:
Bermudagrass Management in the Southern Piedmont USA

al., 1994). Summed to 1-m depth, SOC content was not different between cropland and conservation reserve. Estimates of potential soil organic C (SOC) and total N (TN) In a shortgrass-steppe with 56 yr of grazing in Colorado, sequestration at depths below the traditional plow layer (i.e., 0–0.3 m) in agricultural systems are needed to improve our understanding of SOC was not different between unharvested and lightly management influences on nutrient cycling and potential greenhouse grazed rangeland at any soil depth increment to 0.9-m gas mitigation. We evaluated the factorial combination of nutrient depth(Reederetal.,2004).Incontrast,SOCwasgreater source (inorganic, inorganic cover crop, and broiler litter) and in four of seven depth increments to 0.9-m depth under forage utilization (unharvested, hayed monthly, and low and high heavily grazed compared with unharvested rangeland. grazing pressure) on profile distribution of and changes in SOC and At the end of 12 yr of grazing on a previously ungrazed TN during the first 5 yr of ‘Coastal’ bermudagrass [Cynodon dactylon mixed-grass rangeland in Wyoming, SOC and TN were (L.) Pers.] management. Nutrient source did not affect SOC and TN greater with light and heavy stocking than an ungrazed in the soil profile. Contents of SOC and TN under haying were lower exclosure at a depth of 0 to 0.3 m, but statistically similar than under other management systems throughout the soil profile. between treatments at a depth of 0 to 0.6 m (Schuman et
Do changes in neighborhood characteristics lead to changes in travel behavior? A structural equations modeling approach

Suburban sprawl has been widely criticized for its contribution to auto dependence. Numerous studies have found that residents in suburban neighborhoods drive more and walk less than their counterparts in traditional environments. However, most studies confirm only an association between the built environment and travel behavior, and have yet to establish the predominant underlying causal link: whether neighborhood design independently influences travel behavior or whether preferences for travel options affect residential choice. That is, residential self-selection may be at work. A few studies have recently addressed the influence of self-selection. However, our understanding of the causality issue is still immature. To address this issue, this study took into account individuals’ self-selection by employing a quasi-longitudinal design and by controlling for residential preferences and travel attitudes. In particular, using data collected from 547 movers currently living in four traditional neighborhoods and four suburban neighborhoods in Northern California, we developed a structural equations model to investigate the relationships among changes in the built environment, changes in auto ownership, and changes in travel behavior. The results provide some encouragement that land-use policies designed to put residents closer to destinations and provide them with alternative transportation options will actually lead to less driving and more walking.
Economic Systems of Foraging, Agricultural, and Industrial Societies

Drawing upon the disciplines of economics, anthropology, statistics, and history, and employing a new and unified analytic approach, Frederic L. Pryor reformulates in this book the entire field of comparative economic systems. He examines large samples of foraging (hunting, gathering and fishing), agricultural, and industrial economies to explore four key questions: What are the distinct economic systems found in each group? Why do certain societies or nations have one economic system rather than another? What impact do economic systems have on the performance of the economy? How do these economic systems develop and change? The results provide a context that allows us to move beyond the chaos of case studies and ideological assertions to gain an overview of the development of economic systems over the millennia. It also raises a series of new analytic and empirical issues that have not hitherto been systematically explored.
Parallel Polarization State Generation

The control of polarization, an essential property of light, is of wide scientific and technological interest. The general problem of generating arbitrary time-varying states of polarization (SOP) has always been mathematically formulated by a series of linear transformations, i.e. a product of matrices, imposing a serial architecture. Here we show a parallel architecture described by a sum of matrices. The theory is experimentally demonstrated by modulating spatially-separated polarization components of a laser using a digital micromirror device that are subsequently beam combined. This method greatly expands the parameter space for engineering devices that control polarization. Consequently, performance characteristics, such as speed, stability, and spectral range, are entirely dictated by the technologies of optical intensity modulation, including absorption, reflection, emission, and scattering. This opens up important prospects for polarization state generation (PSG) with unique performance characteristics with applications in spectroscopic ellipsometry, spectropolarimetry, communications, imaging, and security.
Quantum collapse of a charged n-dimensional BTZ-like domain wall

We investigate both the classical and quantum gravitational collapse of a massive, charged, nonrotating n-dimensional Banados–Teitelboim–Zanelli (BTZ)-like domain wall in AdS space. In the classical picture, we show that, as far as the asymptotic observer is concerned, the details of the collapse depend on the amount of charge present in the domain wall; that is, if the domain wall is extremal, nonextremal or overcharged. In both the extremal and nonextremal cases, the collapse takes an infinite amount of observer time to complete. However, in the over-charged case, the collapse never actually occurs, instead one finds an oscillatory solution which prevents the formation of a naked singularity. As far as the infalling observer is concerned, in the nonextremal case, the collapse is completed within a finite amount of proper time. Thus, the gravitational collapse follows that of the typical formation of a black hole via gravitational collapse. Quantum mechanically, we take the absence of induced quasi-parti...
On convexity of the regular set of conical Kahler-Einstein metrics

In this note we prove convexity, in the sense of Colding-Naber, of the regular set of solutions to some complex Monge-Ampere equations with conical singularities along simple normal crossing divisors. In particular, any two points in the regular set can be joined by a smooth minimal geodesic lying entirely in the regular set. We show that as a result, the classical theorems of Myers and Bishop-Gromov extend almost verbatim to this singular setting.
Humoral immunity and heart disease: postpericardiotomy syndrome.

Historically it was adults with rheumatic heart disease and mitral stenosis who first suffered from the common postoperative complication of the postpericardiotomy syndrome (PPS). Fever appeared or persisted beyond the first postoperative week together with signs and symptoms of pericardial reaction: chest pain, pericardial friction rub, electrocardiographic as well as radiographic evidence of pericarditis and often of pericardial and pleural effusions, together with leukocytosis and less specific sign of inflammation. In the setting of rheumatic mitral stenosis, it was natural to assume that this postoperative illness was due to reactivation of rheumatic fever and to treat the patients with medication considered beneficial in acute rheumatic fever: salicylates or steroids.
Some fundamental limitations of mathematical software revealed by the calculation of spacetime curvature

The use of library mathematical software will, ideally, provide solutions to problems in science and engineering without the user having to become involved in the details of the software. In practice, some knowledge of the characteristics of the problem is often required to arrive at an acceptable solution. We illustrate this requirement with the solution of the Einstein field equations to calculate spacetime curvature. These equations under certain circumstances can become more difficult to solve with increasing problem time, and eventually cause a failure in the calculations, which we think will occur no matter what mathematical software is used.
Soliton propagation with up- and down-sliding-frequency guiding filters

We analyze the effect of the third-order guiding filter term on soliton transmission in optical fibers. We find that this term causes a significant difference between the regimes of up- and down-sliding of filter frequency. In particular, the use of up-sliding requires less additional amplifier gain than down-sliding does, which is preferable in real systems.
Manager Incentives and Turnover of Managers: Evidence from the Czech Republic

The association between corporate performance, managers and incentives is a much studied topic. One strand of literature has been motivated by the notion that financial incentives for managers, in the form of performance contracts, equity ownership and so on, could help align the interest of owners and managers: that is, reduce principal-agent problems, and thereby improve corporate performance and increase market valuation. This topic has been studied extensively (for example, see Murphy, 1985, for the effect of performance contracts on market valuation of firms in the United States, and World Bank, 1996b, for a review of performance contracts for state enterprises). The general finding is that these incentives do not work well for state enterprises, especially in developing countries (and the focus of improving state enterprises’ performance has subsequently shifted to privatization), but work reasonably well for private firms in developed market economies (Jensen and Zimmermann, 1985). Recent theoretical models (Aghion et al., 1994; Blanchard and Aghion, 1996) build on the existing literature and investigate the importance of incentive systems for executive performance in the context of transition economies. Some empirical evidence on the link between executive compensation and enterprise productivity growth during the initial transition period is becoming available (see Jones and Kato, 1996, for a study of Bulgarian firms).
Alkaloid-Catalyzed Enantioselective [3 + 2] Cycloaddition of Ketenes and Azomethine Imines

A new asymmetric synthesis of bicyclic pyrazolidinones through an alkaloid-catalyzed formal [3 + 2] cycloaddition of in situ generated ketenes and azomethine imines is described. The products were formed in good to excellent yields (52–99% for 17 examples), with good to excellent diastereoselectivity (dr 5:1 to 27:1 for 11 examples), and with excellent enantioselectivity in all cases (≥96% ee). This method represents the first unambiguous example of an enantioselective reaction between ketenes and a 1,3-dipole.
Leadership and the Mandate of Heaven: Political Risk in China

Abstract. China has experienced very impressive economic growth over the past three decades and has raised millions of people out of poverty in a short period of time. This economic miracle has brought prosperity to millions and extreme wealth to some. China now faces slower growth and a number of other obstacles which may undermine its stability. This paper explores the problems facing modern China by looking back at history and using current social science research as a predictor of potential unrest and political instability. Keywords. China, Political risk, Globalization, Geopolitics. JEL. J11, F51, O53.
High speed optical detectors for monolithic millimeter wave integrated circuits

Metal-semiconductor-metal photodiodes with interdigitated Schottky barrier fingers are being developed for applications in monolithic optical receiver circuits with the purpose of detecting millimeter-wave modulation signals being transmitted via an optical carrier. The devices are planar and incorporate submicron finger spacings and a thin absorption region for speed with a buried stack of tuned Bragg reflectors for enhanced sensitivity at the carrier wavelength. These devices are being integrated with short-gate MODFET (modulation-doped field-effect transistor) amplifiers to form the complete monolithic integrated optical receiver circuit. Device measurements indicate a top surface reflectance of 0.5% with an operation bandwidth in excess of 40 GHz and a dynamic range of 33 dB. >
A circuit model of human whole blood in a microfluidic dielectric sensor

Dielectric spectroscopy (DS) is a powerful monitoring technique that can extract important molecular and cellular properties from a variety of biological materials. DS measurements on human whole blood can reveal a wealth of physiologic information, primarily from the dispersion region that arises from interfacial polarization of red blood cells (RBCs) [1]. Specifically, the use of DS to monitor the blood coagulation process (i.e., dielectric coagulometry) enables rapid and comprehensive assessment of patients' blood coagulation status at the point-of-care (POC) [2]. However, the ratio of RBC volume to total blood volume, or hematocrit (Hct) value, is a confounding parameter in dielectric coagulometry and thus important to analyze using DS. Comprehensive DS analysis on human whole blood has thus far been limited to bulk-solution measurements using ∼mL sample volumes [1]. On the other hand, DS analysis on a single drop of blood (∼10μL) in a microfluidic dielectric sensor presents challenges due to the increased effect of the capacitive double-layer (CDL) formed at electrode surfaces (electrode polarization) due to the scaling of electrode dimensions.
A connected sum formula for involutive Heegaard Floer homology

We prove a connected sum formula for involutive Heegaard Floer homology, and use it to study the involutive correction terms of connected sums. In particular, we give an example of a three-manifold with $$\underline{d}(Y) \ne d(Y) \ne \bar{d}(Y)$$ . We also construct a homomorphism from the three-dimensional homology cobordism group to an algebraically defined Abelian group, consisting of certain complexes (equipped with a homotopy involution) modulo a notion of local equivalence.
Microgrid Reference Methodology for Understanding Utility and Customer Interactions in Microgrid Projects

Abstract A holistic and systematic approach, based in key concepts of systems thinking, systems of systems and management science, can be employed to completely represent, model and analyze microgrid systems. This proposed Microgrid Reference Methodology can guide electric utilities and industrial customers in cooperating to attain the mutual benefits of microgrid projects.
N-Terminal Pro-B-Type Natriuretic Peptide and Risk of Future Cognitive Impairment in the REGARDS Cohort

Background Improved understanding of the etiology of cognitive impairment is needed to develop effective preventive interventions. Higher amino-terminal pro-B-type natriuretic peptide (NT-proBNP) is a biomarker of cardiac dysfunction associated with risk of cardiovascular diseases and stroke in apparently healthy people. Objective To study the association of NT-proBNP with risk of incident cognitive impairment. Methods The Reasons for Geographic and Racial Differences in Stroke is a national cohort study of 30,239 black and white Americans age 45 and older at baseline, enrolled in 2003-7. Among participants without prebaseline stroke or cognitive impairment, baseline NT-proBNP was measured in 470 cases of incident cognitive impairment and 557 controls. Cases were participants scoring below the 6th percentile of demographically-adjusted means on at least 2 of 3 serially administered tests (word list learning, word list recall and semantic fluency) over 3.5 years follow-up. Results Adjusting for age, gender, race, region of residence, education, and income, there was an increased odds ratio of incident cognitive impairment with increasing NT-proBNP; participants in the 4th versus 1st quartile (>127 versus ≤33 pg/ml) had a 1.69-fold increased odds (95% CI 1.11-2.58). Adjustment for cardiovascular risk factors and presence of an apolipoprotein E4 allele had no substantial impact on the odds ratio. Results did not differ by age, race, gender, or presence of an apolipoprotein E4 allele. Conclusion Higher NT-pro-BNP was associated with incident cognitive impairment in this prospective study, independent of atherogenic and Alzheimer's disease risk factors. Future work should clarify pathophysiologic connections of NT-proBNP and cognitive dysfunction.
Benefits of Surgical Smoothing and Spare Capacity: An Econometric Analysis of Patient Flow

In this study, we examine the hospital's ability to admit patients from its emergency department. From a medical perspective, the number of patients being admitted should depend solely on the patients’ clinical conditions. Using a large-scale econometric study that includes detailed operational and clinical data on all cardiac patient encounters from a set of 128 hospitals over a period of four years, we show that this is not the case. In particular, we find that independent of their medical condition, many emergency patients are denied hospital admission because of a lack of inpatient beds. Our analysis suggests that having one more inpatient bed at the start of a day can increase the likelihood of an emergency room patient admission by around 3% on average. We examine two policies – active discharge and demand smoothing – that can help hospitals improve patient access. We find that some hospitals actively discharge inpatients when beds become scarce; hospitals that follow such an active discharge protocol are, on average, able to admit more patients. We also investigate to what extent the hospital's ability to smooth its surgical schedule impacts hospital admissions. Hospitals tend to schedule their elective patients early in the week (Mondays and Tuesdays), and discharge them by the weekend in order to minimize weekend staffing, effectively maximizing bed occupancy during the middle of the week. This “weekend effect” artificially induces variability, and reduces effective system capacity. We find that by scheduling patients more uniformly over the week, hospitals can dramatically increase patient access, obviating the need for active discharges or additional capacity investment. Our analysis quantifies these effects, and can help hospitals make effective capacity management decisions in order to improve patient flow.
Cross-validated wavelet block thresholding for non-Gaussian errors

Wavelet thresholding generally assumes independent, identically distributed normal errors when estimating functions in a nonparametric regression setting. VisuShrink and SureShrink are just two of the many common thresholding methods based on this assumption. When the errors are not normally distributed, however, few methods have been proposed. A distribution-free method for thresholding wavelet coefficients in nonparametric regression is described, which unlike some other non-normal error thresholding methods, does not assume the form of the non-normal distribution is known. Improvements are made to an existing even-odd cross-validation method by employing block thresholding and level dependence. The efficiency of the proposed method on a variety of non-normal errors, including comparisons to existing wavelet threshold estimators, is shown on simulated data.
Nanoengineered Surfaces for Thermal Energy Conversion

We provide an overview of the impact of using nanostructured surfaces to improve the performance of solar thermophotovoltaic (STPV) energy conversion and condensation systems. We demonstrated STPV system efficiencies of up to 3.2%, compared to ≤1% reported in the literature, made possible by nanophotonic engineering of the absorber and emitter. For condensation systems, we showed enhanced performance by using scalable superhydrophobic nanostructures via jumping-droplet condensation. Furthermore, we observed that these jumping droplets carry a residual charge which causes the droplets to repel each other mid-flight. Based on this finding of droplet residual charge, we demonstrated electric-field-enhanced condensation and jumping-droplet electrostatic energy harvesting.
Applying the Ecosystem Metaphor to Entrepreneurship: Uses and Abuses

This article uses a comparison of the generic features of natural ecosystems and the popular use of the term “entrepreneurship ecosystems” and identifies five mistakes in the way the ecosystem meta...
Digital Adultery, “Meta-Anon Widows,” Real-World Divorce, and the Need for a Virtual Sexual Ethic

Ethical issues that have emerged around relationships in virtual worlds can inform the way we approach the ethics of human/robot relationships. A workable ethic would be one that treats marriage as an enduring human institution and, while we value robots as worthy works of our hands, they are inappropriate partners for marital or sexual relationships.
Deciding equivalence with sums and the empty type

The logical technique of focusing can be applied to the λ-calculus; in a simple type system with atomic types and negative type formers (functions, products, the unit type), its normal forms coincide with βη-normal forms. Introducing a saturation phase gives a notion of quasi-normal forms in presence of positive types (sum types and the empty type). This rich structure let us prove the decidability of βη-equivalence in presence of the empty type, the fact that it coincides with contextual equivalence, and with set-theoretic equality in all finite models.
Simulating the Cranfield geological carbon sequestration project with high-resolution static models and an accurate equation of state.

In this study, a field-scale carbon dioxide (CO2) injection pilot project was conducted as part of the Southeast Regional Sequestration Partnership (SECARB) at Cranfield, Mississippi. We present higher-order finite element simulations of the compositional two-phase CO2-brine flow and transport during the experiment. High- resolution static models of the formation geology in the Detailed Area Study (DAS) located below the oil- water contact (brine saturated) are used to capture the impact of connected flow paths on breakthrough times in two observation wells. Phase behavior is described by the cubic-plus-association (CPA) equation of state, which takes into account the polar nature of water molecules. Parameter studies are performed to investigate the importance of Fickian diffusion, permeability heterogeneity, relative permeabilities, and capillarity. Simulation results for the pressure response in the injection well and the CO2 breakthrough times at the observation wells show good agreement with the field data. For the high injection rates and short duration of the experiment, diffusion is relatively unimportant (high P clet numbers), while relative permeabilities have a profound impact on the pressure response. High-permeability pathways, created by fluvial deposits, strongly affect the CO2 transport and highlight the importance of properly characterizing the formation heterogeneity in future carbon sequestrationmore » projects.« less
The Perfect Glass Paradigm: Disordered Hyperuniform Glasses Down to Absolute Zero.

Rapid cooling of liquids below a certain temperature range can result in a transition to glassy states. The traditional understanding of glasses includes their thermodynamic metastability with respect to crystals. However, here we present specific examples of interactions that eliminate the possibilities of crystalline and quasicrystalline phases, while creating mechanically stable amorphous glasses down to absolute zero temperature. We show that this can be accomplished by introducing a new ideal state of matter called a “perfect glass”. A perfect glass represents a soft-interaction analog of the maximally random jammed (MRJ) packings of hard particles. These latter states can be regarded as the epitome of a glass since they are out of equilibrium, maximally disordered, hyperuniform, mechanically rigid with infinite bulk and shear moduli, and can never crystallize due to configuration-space trapping. Our model perfect glass utilizes two-, three-, and four-body soft interactions while simultaneously retaining the salient attributes of the MRJ state. These models constitute a theoretical proof of concept for perfect glasses and broaden our fundamental understanding of glass physics. A novel feature of equilibrium systems of identical particles interacting with the perfect-glass potential at positive temperature is that they have a non-relativistic speed of sound that is infinite.
SEC Investigations and Securities Class Actions: An Empirical Comparison

Using actions with both an SEC investigation and a class action as our baseline, we compare the targeting of SEC-only investigations with class-action-only lawsuits. Looking at measures of information asymmetry, we find that investors in the market perceive greater information asymmetry following the public announcement of the underlying violation for class-action-only lawsuits compared with SEC-only investigations. Turning to sanctions, we find that the incidence of top officer resignation is greater for class-action-only lawsuits relative to SEC-only investigations. Our findings are consistent with the private enforcement targeting disclosure violations at least as precisely as (if not more so than) SEC enforcement.
BITCOIN 1, BITCOIN 2, ....: AN EXPERIMENT IN PRIVATELY ISSUED OUTSIDE MONIES

The value of Bitcoin depends upon self-fulfilling beliefs that are hard to pin down. We demonstrate this for the case where Bitcoin is the only form of money in the economy and then generalize the message to the case of multiple Bitcoin clones and/or a competing sovereign currency. Some aspects of the indeterminacy we describe would no longer hold if Bitcoin were an interesting-bearing object.
A hybrid sampling scheme for triangle counting

We study the problem of estimating the number of triangles in a graph stream. No streaming algorithm can get sublinear space on all graphs, so methods in this area bound the space in terms of parameters of the input graph such as the maximum number of triangles sharing a single edge. We give a sampling algorithm that is additionally parameterized by the maximum number of triangles sharing a single vertex. Our bound matches the best known turnstile results in all graphs, and gets better performance on simple graphs like G(n, p) or a set of independent triangles.We complement the upper bound with a lower bound showing that no sampling algorithm can do better on those graphs by more than a log factor. In particular, any insertion stream algorithm must use [EQUATION] space when all the triangles share a common vertex, and any sampling algorithm must take T1/3 samples when all the triangles are independent. We add another lower bound, also matching our algorithm's performance, which applies to all graph classes. This lower bound covers "triangle-dependent" sampling algorithms, a subclass that includes our algorithm and all previous sampling algorithms for the problem.
NAPR: a Cloud-Based Framework for Neuroanatomical Age Prediction.

The availability of cloud computing services has enabled the widespread adoption of the “software as a service” (SaaS) approach for software distribution, which utilizes network-based access to applications running on centralized servers. In this paper we apply the SaaS approach to neuroimaging-based age prediction. Our system, named “NAPR” (Neuroanatomical Age Prediction using R), provides access to predictive modeling software running on a persistent cloud-based Amazon Web Services (AWS) compute instance. The NAPR framework allows external users to estimate the age of individual subjects using cortical thickness maps derived from their own locally processed T1-weighted whole brain MRI scans. As a demonstration of the NAPR approach, we have developed two age prediction models that were trained using healthy control data from the ABIDE, CoRR, DLBS and NKI Rockland neuroimaging datasets (total N = 2367, age range 6–89 years). The provided age prediction models were trained using (i) relevance vector machines and (ii) Gaussian processes machine learning methods applied to cortical thickness surfaces obtained using Freesurfer v5.3. We believe that this transparent approach to out-of-sample evaluation and comparison of neuroimaging age prediction models will facilitate the development of improved age prediction models and allow for robust evaluation of the clinical utility of these methods.
Stimulating the Vote: ARRA Road Spending and Vote Share

This paper estimates the impact of public good spending on voting behavior in the United States, using a quasi-experimental design and the distribution of American Recovery and Reinvestment Act (ARRA) road projects in New Jersey. I find an approximate 1.5 percentage point increase in Democratic Party presidential vote share in areas close to highway and bridge expenditures. I consider two alternative mechanisms: one, a salience mechanism whereby spending and associated "funded-by" signage affect political preferences; the other, a possible political multiplier effect whereby stimulus spending improves local economic outcomes, generating incumbent votes. Evidence is inconsistent with the later explanation.
Relative permittivity in the electrical double layer from nonlinear optics

Second harmonic generation (SHG) spectroscopy has been applied to probe the fused silica/water interface at pH 7 and the uncharged 11¯02 sapphire/water interface at pH 5.2 in contact with aqueous solutions of NaCl, NaBr, NaI, KCl, RbCl, and CsCl as low as several 10 μM. For ionic strengths up to about 0.1 mM, the SHG responses were observed to increase, reversibly for all salts surveyed, when compared to the condition of zero salt added. Further increases in the salt concentration led to monotonic decreases in the SHG response. The SHG increases followed by decreases are found to be consistent with recent reports of phase interference and phase matching in nonlinear optics. By varying the relative permittivity employed in common mean field theories used to describe electrical double layers and by comparing our results to available literature data, we find that models recapitulating the experimental observations are the ones in which (1) the relative permittivity of the diffuse layer is that of bulk water, with other possible values as low as 30, (2) the surface charge density varies with salt concentration, and (3) the charge in the Stern layer or its thickness varies with salt concentration. We also note that the experimental data exhibit sensitivity depending on whether the salt concentration is increased from low to high values or decreased from high to low values, which, however, is not borne out in the fits, at least within the current uncertainties associated with the model point estimates.
MEGA PROSTHESIS FOR DISTAL FEMORAL PERI-PROSTHETIC FRACTURES – OPPOSES

Peri-prosthetic fractures above a TKA are becoming increasingly more common, and typically occur at the junction of the anterior flange of the femoral component and the osteopenic metaphyseal distal femur. In the vast majority of cases the TKA is well fixed and has been functioning well prior to fracture. For loose components, revision is typically indicated. Often, distal femoral mega prostheses are required to deal with metaphyseal bone loss. Good results have been reported in small series, however, complications, including infection remain concerning, and these implants are incredibly expensive. Although performing a mega prosthesis in the setting of a well fixed TKA is not unreasonable due to immediate full weight bearing, in my opinion, prosthetic replacement should be limited to cases of failed ORIF (rare), or in cases where fixation is likely to fail (i.e., severe osteolysis distally). For the majority of fractures above well fixed components, internal fixation is preferred for the main reason that the overwhelming majority of these fractures will heal. Fixation options include retrograde nailing or lateral locked plating. Nails are typically considered in arthroplasties that allow intercondylar access (“open box PS” or CR implants) and have sufficient length of the distal fragment to allow multiple locking screws to be used. This situation is rare, as most distal fragments are quite short. If a nail is chosen, use of a long nail is preferred, since it allows the additional fixation and alignment that diaphyseal fill affords. Short nails should be discouraged since they can “toggle” in the meta-diaphysis and do not engage the diaphysis to improve coronal alignment. Plates can be used with any implant type and any length of distal fragment. The challenge with either fixation strategy is obtaining stable fixation of the distal fragment while maintaining length, alignment, and rotation. Fixation opportunities in the distal fragment can be limited due to obstacles caused by femoral component lugs, boxes, stems, cement mantles, and areas of stress shielding or osteolysis. Modern lateral locked plates can be inserted in a biologically friendly submuscular extra-periosteal fashion. More recent developments with polyaxial locked screws (that allow angulation prior to end-point locking) may offer even more versatility when distal fragment fixation is challenging. The goal of fixation is to obtain as many long locked screws in the distal fragment as possible. High union rates have been reported with modern locked plating techniques, however, biplanar fluoroscopic vigilance is required to prevent malalignments, typically valgus, distraction, and distal fragment hyperextension.
UKA: THE GOLD STANDARD FOR MEDIAL COMPARTMENT DISEASE – OPPOSES

There exists a variety of options for a medial compartment knee with osteoarthritis, specifically a unicompartmental knee, high tibial osteotomy, and total knee arthroplasty. This surgeon prefers a rotating platform posterior stabilised total knee to the unicompartmental knee. Unicompartmental knee arthroplasty (UKA) in younger patients is being performed with increasing frequency. While UKA is a powerful marketing tool because of its minimally invasive nature and quality of knee function that is superior to the total knee arthroplasty (TKA), it has tremendous drawbacks. These include: the selection criteria is very specific and the number of patients that fit in that category is small, there is a steep learning curve for the surgeon to perfect the technique, higher failure due to wear and loss of fixation, and unexplained pain. Based on level 1 and 2 evidence available it is not justified to do more UKAs at present when the results of a TKA are so successful.
Short Selling Around Restatement Announcements When Do Bears Pounce

This article draws on two distinct literatures—one that investigates the impact of accounting restatements and another that investigates the trading behavior of short sellers—to further our understanding of how sophisticated investors process and respond to news about accounting corrections. We examine short-seller behavior in the days surrounding restatement announcements to determine when short sellers identify restatements and how they trade on restatement news. Our findings suggest that short sellers do not appear to anticipate restatement announcement dates, but we find that abnormal short selling is significantly higher than is typical when restatements are announced, especially for restatements announced transparently (i.e., in press releases or 8-Ks). Short sellers target small companies, whose information environments may be weaker, and companies making restatements that reduce previously reported income. In addition, we find that restating companies targeted most heavily by short sellers experie...
Heavy quark physics on the lattice

I review the current status of lattice calculations of the properties of bound states containing one or more heavy quarks. Many of my remarks focus on the heavy-light leptonic decay constants, such as fB, for which the systematic errors have by now been quite well studied. I also discuss B-parameters, semileptonic form factors, and the heavy-light and heavy-heavy spectra. Some of my “world averages” are: fB = 200(30) MeV, , fBs / fB = 1.16(4) and .
A MODULAR METAPHYSEAL SLEEVE: A STRAIGHT STEM ALTERNATIVE

There is no mathematical relationship between the internal diameter of the femoral metaphysis and diaphysis. Unless an infinite number of monolithic stems are available with variable metaphyseal and diaphyseal diameters, which is not economically possible, even in virgin cases, the surgeon has to decide if the stem is going to fit in the metaphysis or the diaphysis. It is not possible to match both. In revision cases with a hollowed out metaphysis, the situation is much worse. As it is obviously easier to fit the diaphysis, this is what stems such as the AML and Wagner stem have done. They completely ignore the metaphysis and obtain fixation in the diaphysis. This is all well and good, but it means that the proximal femur is unloaded, like an astronaut in space. While, there will be some recovery due to removal of the toxins and local muscle pull, it will be incomplete. Furthermore, should sepsis occur, one is faced with the horror of removing a distally fixed implant. Clearly, if proximal fixation, i.e. above the level of lesser trochanter could reliably be achieved, this would be preferable in terms of proximal loading leading to bone recovery and ease of removal should it be required. The only way that proximal loading can be achieved is if the metaphyseal and diaphyseal parts of the component can be varied infinitely. This clearly can only be achieved by using a modular stem. The concern with modularity always has been fretting at the sleeve-stem locking mechanism with release of metal ions. The stem, which I have been using for the last 25 years, is the SROM stem. Fretting and ion release had never been an issue. As the components are made of a relatively soft titanium alloy, it is likely that the sleeve and the stem cold weld, thus, eliminating any movement and eliminating friction. I have a follow-up of roughly 120 revision cases with a minimum follow-up of 5 years and a maximum follow-up of 22 years. I have no loosening in easy revision cases where a primary stem was used. I have had some loosenings in extremely difficult revision situations where a long bowed stem was required, but even then, the loosening rate is less than 3%. I use this stem in primary situations, i.e. in about 80% of all the primaries I have done. This means I have done roughly 1500 cases or more. Other than some late infections, I have never, ever had any stem loosening in a simple case. Obviously, I have had loosenings in some cases, where we have been doing fancy shortening or de-rotation osteotomies, but none in simple primary cases. I would, therefore, suggest that the surgeon, if he wishes to use this stem, please try it out on some simple primary cases. The ability to vary distal and proximal internal diameters and proximal geometry makes for easy surgery. I have been using this stem for 25 years and continue to use it in all my primary noncemented cases. I believe in the adage of “train hard and fight easy.” I think that surgeons should not get themselves into a situation where they are forced in a difficult case to use something they have never seen before.
Resonant Compton upscattering in anomalous X-ray pulsars

A significant new development in the study of Anomalous X-ray Pulsars (AXPs) has been the recent discovery by INTEGRAL and RXTE of flat, hard X-ray components in three AXPs. These non-thermal spectral components differ dramatically from the steeper quasi-power-law tails seen in the classic X-ray band in these sources. A prime candidate mechanism for generating this new component is resonant, magnetic Compton upscattering. This process is very efficient in the strong magnetic fields present in AXPs. Here an introductory exploration of an inner magnetospheric model for upscattering of surface thermal X-rays in AXPs is offered, preparing the way for an investigation of whether such resonant upscattering can explain the 20–150 keV spectra seen by INTEGRAL. Characteristically flat emission spectra produced by non-thermal electrons injected in the emission region are computed using collision integrals. A relativistic QED scattering cross section is employed so that Klein–Nishina reductions are influential in determining the photon spectra and fluxes. Spectral results depend strongly on the magnetospheric locale of the scattering and the observer’s orientation, which couple directly to the angular distributions of photons sampled.
Geometry of domains with the uniform squeezing property

Abstract We introduce the notion of domains with uniform squeezing property, study various analytic and geometric properties of such domains and show that they cover many interesting examples, including Teichmuller spaces and Hermitian symmetric spaces of non-compact type. The properties supported by such manifolds include pseudoconvexity, hyperconvexity, Kahler-hyperbolicity, vanishing of cohomology groups and quasi-isometry of various invariant metrics. It also leads to nice geometric properties for manifolds covered by bounded domains and a simple criterion to provide positive examples to a problem of Serre about Stein properties of holomorphic fiber bundles.
Fragility of decentralized load-side frequency control in stochastic environment

In this paper, we demonstrate the fragility of decentralized load-side frequency algorithm proposed in [1] against stochastic parametric uncertainty in power network model. The stochastic parametric uncertainty is motivated through the presence of renewable energy resources in power system model. We show that relatively small variance value of the parametric uncertainty affecting the system bus voltages cause the decentralized load-side frequency regulation algorithm to become stochastically unstable. The critical variance value of the stochastic bus voltages above which the decentralized control algorithm become mean square unstable is computed using an analytical framework developed in [2], [3]. Furthermore, the critical variance value is shown to decrease with the increase in the cost of the controllable loads and with the increase in penetration of renewable energy resources. Finally, simulation results on IEEE 68 bus system are presented to verify the main findings of the paper.
The Returns to Nursing: Evidence from a Parental-Leave Program

In this article, we quantify the effects of nurses on health care delivery and patient health in the context of an unintended and policy-induced nurse shortage. Our empirical strategy takes advantage of a parental-leave program in Denmark, which offered any parent the opportunity to take up to one year’s absence per child aged 0–8. Combining the policy variation with administrative employer–employee match data, we document substantial program take-up among nurses, who could not be replaced on net despite public education and immigration expansion efforts to mitigate the employment effects. We find that the parental leave program reduced hospital and nursing home nurse employment by 15% and 10%, respectively. Using detailed patient health records, we find detrimental effects on hospital-care delivery as indicated by a large increase in 30-day readmission rates among acute myocardial infarction patients. We find no evidence for an increase in hospital mortality. In nursing homes, we estimate a large increase in mortality.
Contextual Motifs: Increasing the Utility of Motifs using Contextual Data

Motifs are a powerful tool for analyzing physiological waveform data. Standard motif methods, however, ignore important contextual information (e.g., what the patient was doing at the time the data were collected). We hypothesize that these additional contextual data could increase the utility of motifs. Thus, we propose an extension to motifs, contextual motifs, that incorporates context. Recognizing that, oftentimes, context may be unobserved or unavailable, we focus on methods to jointly infer motifs and context. Applied to both simulated and real physiological data, our proposed approach improves upon existing motif methods in terms of the discriminative utility of the discovered motifs. In particular, we discovered contextual motifs in continuous glucose monitor (CGM) data collected from patients with type 1 diabetes. Compared to their contextless counterparts, these contextual motifs led to better predictions of hypo- and hyperglycemic events. Our results suggest that even when inferred, context is useful in both a long- and short-term prediction horizon when processing and interpreting physiological waveform data.
Probability estimation of CO2 leakage through faults at geologic carbon sequestration sites

Abstract Leakage of CO 2 and brine along faults at geologic carbon sequestration (GCS) sites is a primary concern for storage integrity. The focus of this study is on the estimation of the probability of leakage along faults or fractures. This leakage probability is controlled by the probability of a connected network of conduits existing at a given site, the probability of this network encountering the CO 2 plume, and the probability of this network intersecting environmental resources that may be impacted by leakage. This work is designed to fit into a risk assessment and certification framework that uses compartments to represent vulnerable resources such as potable groundwater, health and safety, and the near-surface environment. The method we propose includes using percolation theory to estimate the connectivity of the faults, and generating fuzzy rules from discrete fracture network simulations to estimate leakage probability. By this approach, the probability of CO 2 escaping into a compartment for a given system can be inferred from the fuzzy rules. The proposed method provides a quick way of estimating the probability of CO 2 or brine leaking into a compartment. In addition, it provides the uncertainty range of the estimated probability.
Optimal regulation response of batteries under cycle aging mechanisms

When providing frequency regulation in a pay-for-performance market, batteries need to carefully balance the trade-off between following regulation signals and their degradation costs in real-time. Existing battery control strategies either do not consider mismatch penalties in pay-for-performance markets, or cannot accurately account for battery cycle aging mechanism during operation. This paper derives an online control policy that minimizes a battery owner's operating cost for providing frequency regulation in a pay-for-performance market. The proposed policy considers an accurate electrochemical battery cycle aging model, and is applicable to most types of battery cells. It has a threshold structure, and achieves near-optimal performance with respect to an offline controller that has complete future information. We explicitly characterize this gap and show it is independent of the duration of operation. Simulation results with both synthetic and real regulation traces are conducted to illustrate the theoretical results.
A new class of combinatorial markets with covering constraints: algorithms and applications

We introduce a new class of combinatorial markets in which agents have covering constraints over resources required and are interested in delay minimization. Our market model is applicable to several settings including scheduling and communicating over a network. This model is quite different from the traditional models, to the extent that neither do the classical equilibrium existence results seem to apply to it nor do any of the efficient algorithmic techniques developed to compute equilibria. In particular, our model does not satisfy the condition of non-satiation, which is used critically to show the existence of equilibria in traditional market models and we observe that our set of equilibrium prices could be a connected, non-convex set. We give a proof of the existence of equilibria and a polynomial time algorithm for finding one, drawing heavily on techniques from LP duality and submodular minimization. Finally, we show that our model inherits many of the fairness properties of traditional equilibrium models as well as new models, such as CEEI.