cssi/SciSciGPT-SciSciNet huggingface dataset:
Thromboprophylaxis is associated with reduced post-hospitalization venous thromboembolic events in patients with inflammatory bowel diseases.

Background & Aims Patients with inflammatory bowel diseases (IBDs) have increased risk for venous thromboembolism (VTE); those who require hospitalization have particularly high risk. Few hospitalized patients with IBD receive thromboprophylaxis. We analyzed the frequency of VTE after IBD-related hospitalization, risk factors for post-hospitalization VTE, and the efficacy of prophylaxis in preventing post-hospitalization VTE. Methods In a retrospective study, we analyzed data from a multi-institutional cohort of patients with Crohn's disease or ulcerative colitis and at least 1 IBD-related hospitalization. Our primary outcome was a VTE event. All patients contributed person-time from the date of the index hospitalization to development of VTE, subsequent hospitalization, or end of follow-up. Our main predictor variable was pharmacologic thromboprophylaxis. Cox proportional hazard models adjusting for potential confounders were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Results From a cohort of 2788 patients with at least 1 IBD-related hospitalization, 62 patients developed VTE after discharge (2%). Incidences of VTE at 30, 60, 90, and 180 days after the index hospitalization were 3.7/1000, 4.1/1000, 5.4/1000, and 9.4/1000 person-days, respectively. Pharmacologic thromboprophylaxis during the index hospital stay was associated with a significantly lower risk of post-hospitalization VTE (HR, 0.46; 95% CI, 0.22–0.97). Increased numbers of comorbidities (HR, 1.30; 95% CI, 1.16–1.47) and need for corticosteroids before hospitalization (HR, 1.71; 95% CI, 1.02–2.87) were also independently associated with risk of VTE. Length of hospitalization or surgery during index hospitalization was not associated with post-hospitalization VTE. Conclusions Pharmacologic thromboprophylaxis during IBD-related hospitalization is associated with reduced risk of post-hospitalization VTE.
The economic implications of preventive health care

Abstract Today's cost-conscious political environment subjects the economic implications of proposed health care expenditures to careful scrutiny. This paper examines both the logic of and the evidence on preventive health care activities' ability to serve the objective of health cost containment. Following a brief introduction to benefit-cost analysis, the paper presents a prevention activity classification schema intended to clarify distinctions among the modalities of prevention and to differentiate activities with significant cost-containment potential from those which seem to offer less potential. Empirical evidence supports the conventional wisdom that primary prevention activities are frequently cost-effective, particularly when the recipient's role is relatively passive (e.g. receiving an immunization) and when the prevention measure is a public good delivered to an entire community (e.g. water fluoridation). The existing success of such traditional public health measures suggests that future prevention opportunities may lie in nontraditional activities which violate “rules” of effective health care delivery or communication of prevention information. For example, the broadcast media may prove to be a cost-effective vehicle for health education, despite the impersonal character of the media and the required “activation” of the viewer/listener. Whatever prevention's long-run cost-containment potential might be, the near-term outlook for support of prevention activities is clouded by the budgetary myopia of the political system, the lack of a vocal constituency for prevention, and a limited base of solid understanding of the health and economic consequences of numerous prevention measures.
Photonic time stretch enhanced recording scope

We demonstrate a new mode of operation for the time stretched A/D converter. The technique is superior to the sampling scope in that it permits the capture of non periodic events such as clustered noise.
A bestiary of higher-dimensional Taub–NUT–AdS spacetimes

We present a menagerie of solutions to the vacuum Einstein equations in six, eight and ten dimensions. These solutions describe spacetimes which are either locally asymptotically AdS or locally asymptotically flat, and which have non-trivial topology. We discuss the global structure of these solutions, and their relevance within the context of M-theory.
Uncertainty Propagation in Integrated Airframe–Propulsion System Analysis for Hypersonic Vehicles

Air-breathing hypersonic vehicles are based on an airframe-integrated scramjet engine. The elongated forebody that serves as the inlet of the engine is subject to harsh aerothermodynamic loading, which causes it to deform. Unpredicted deformations may produce unstart, combustor chocking, or structural failure due to increased loads. An uncertainty quantification framework is used to propagate the effects of aerothermoelastic deformations on the performance of the scramjet engine. A loosely coupled airframe-integrated scramjet engine is considered. The aerothermoelastic deformations calculated for an assumed trajectory and angle of attack are transferred to a scramjet engine analysis. Uncertainty associated with deformation prediction is propagated through the engine performance analysis. The effects of aerodynamic heating and aerothermoelastic deformations at the cowl of the inlet are the most significant. The cowl deformation is the main contributor to the sensitivity of the propulsion system performance...
Notas sobre el problema autor y su función

En este articulo se recuperan algunas de las reflexiones utilizadas en la teoria literaria y los estudios culturales que, sacudidos por el caso Sokal , intentan explicar la funcion de la categoria autor . En particular, sirven de apoyo para sostener que autor es una categoria colectiva, un tipo de ideologema, un mecanismo ecoico, argumentos expuestos por Barthes, Foucault, Bourdieu, Jameson y Vattimo, entre otros. Se anaden tambien notas historiograficas de la evolucion del concepto autor de la mano de los estudios de Burke, que nos ayudan a apreciar que el registro autor fue una jugada comercial, durante la etapa tardia de la Edad Media y el comienzo del Renacimiento, para certificar como propiedad individual la distribucion del conocimiento social.
On conserved quantities at spatial infinity

There is a well-known short list of asymptotic conserved quantities for a physical system at spatial infinity. We search for new ones. This is carried out within the asymptotic framework of Ashtekar and Romano, in which spatial infinity is represented as a smooth boundary of space–time. We first introduce, for physical fields on space–time, a characterization of their asymptotic behavior as certain fields on this boundary. Conserved quantities at spatial infinity, in turn, are constructed from these fields. We find, in Minkowski space–time, that each of a Klein–Gordon field, a Maxwell field, and a linearized gravitational field yields an entire hierarchy of conserved quantities. Only certain quantities in this hierarchy survive into curved space–time.
The Far-Infrared Radio Correlation at High-z : Prospects for the SKA

In this conference proceedings article I summarize the recent work of Murphy (2009) which presents physically motivated predictions for the evolution of the Far-Infrared--radio correlation as a function of redshift arising from variations in the cosmic-ray (CR) electron cooling time-scales as Inverse Compton (IC) scattering off of the Cosmic Microwave Background (CMB) becomes increasingly important.
Regional center for complex colonoscopy: yield of neoplasia in patients with prior incomplete colonoscopy

Background and Aims Incomplete colonoscopy increases the risk of incident proximal colon cancer postcolonoscopy. Incomplete colonoscopy is often followed by barium enema or CT colonography. We sought to describe the yield of completion colonoscopy in a regional center for complex colonoscopy. Methods This is a retrospective cohort study of 520 consecutive patients referred to a single colonoscopist over a 14-year period for completion colonoscopy after a previous incomplete examination. Results Colonoscopy was completed to the cecum in 506 of 520 patients (97.3%). A total of 913 conventional adenomas was removed in 277 patients (adenoma detection rate 53.3%). There were 184 adenomas ≥ 1 cm in size or with advanced pathology. There were 525 serrated-class lesions removed in 175 patients, including 54 sessile serrated polyps in 26 patients and 41 hyperplastic polyps greater than 1 cm in 26 patients. Nine colorectal cancers were found. We estimated that approximately 57% of the conventional adenomas, 58% of the sessile serrated polyps, 27% of the hyperplastic polyps, and all 9 cancers detected by the completion colonoscopy were beyond the extent of the previous examination. Conclusions The yield of completion colonoscopy in a cohort of patients with previous failed cecal intubation was substantial. Regional centers for complex colonoscopy can provide high rates of cecal intubation in cases of incomplete colonoscopy and high yields of lesions in these cases. The regional center for complex colonoscopy is an important medical service.
Asymmetric Hydrogenations for the Synthesis of Boc-Protected 4-Alkylprolinols and Prolines

The utility of 4-substituted prolinols and their corresponding prolines in peptides, peptidomimetics, and natural products has motivated researchers to find new and efficient routes for their preparation. Herein, we report a general approach to the synthesis of Boc-protected 4-alkylprolinols and prolines via a divergent asymmetric hydrogenation strategy. Intermediate exocyclic olefins were prepared by Wittig-type reactions with ketone 6 and subjected to hydroxyl and sterically directed reductions. The Crabtree catalyst (Ir[COD]PyPCy3PF6) proved to be highly effective in diastereoselective hydrogenations to give trans-substituted pyrrolidines (9). Good facial selectivities were also observed in heterogeneous hydrogenations with Raney-nickel to obtain cis-substituted pyrrolidines (11). Employing this strategy, we describe the synthesis of novel prolinol and proline-based building blocks for incorporation into biologically relevant peptidomimetics.
Converse Lyapunov functions for exponentially stable periodic orbits

Abstract In this paper, we present a technique for constructing a class of quadratic Lyapunov functions for exponentially stable periodic orbits. This construction is facilitated by the use of a special set of local coordinates that serve to highlight the tangential and transverse dynamics of the system.
On system state equipartitioning and semistability in network dynamical systems with arbitrary time-delays

In many applications involving multiagent systems, groups of agents are required to agree on certain quantities of interest. In particular, it is important to develop consensus protocols for networks of dynamic agents with directed information flow, switching network topologies, and possible system time-delays. In this paper, we use compartmental dynamical system models to characterize dynamic algorithms for linear and nonlinear networks of dynamic agents in the presence of inter-agent communication delays that possess a continuum of semistable equilibria, that is, protocol algorithms that guarantee convergence to Lyapunov stable equilibria. In addition, we show that the steady-state distribution of the dynamic network is uniform, leading to system state equipartitioning or consensus. These results extend the results in the literature on consensus protocols for linear balanced networks to linear and nonlinear unbalanced networks with time-delays.
Synthesis of functionalized bicyclo[3.2.1]octan-6-ones for diterpenoids: allylsilane directed Pummerer reaction: insertion reactions of diazoketones

The sulfide 5 underwent Pummerer cyclization to give 6 , whereas the allyl silane analog 10 produced the bicyclo[3.2.1]octanones 11 and 11a . Extension of this methodology to 15 resulted in 16 without the necessity for allyl silane activation. The intermediate diazoketone 14 on treatment with BF 3 ·OEt 2 gave 17 , 18 and 19 , whereas the saturated adduct 22 on treatment with Rh 2 (OAc) 4 gave 23 .
Quality of a 28 cm Long LYSO Crystal and Progress on Optical and Scintillation Properties

Because of their high stopping power and fast and bright scintillation, cerium doped LSO and LYSO crystals have attracted a broad interest in the physics community pursuing precision electromagnetic calorimeter for future high energy physics experiments. Their excellent radiation hardness against γ -rays, neutrons and charged hadrons also makes them a preferred material for calorimeters to be operated in a severe radiation environment, such as the HL-LHC. An effort was made at SIPAT to grow 25 X0 (28 cm) long LYSO crystals for high energy physics applications. In this paper, the optical and scintillation properties and its radiation hardness against γ -ray irradiations up to 1 Mrad are presented for the first 2.5×2.5×28 cm LYSO sample. An absorption band was found at the seed end of this sample and three other long samples, which was traced back to a bad seed crystal used in the corresponding crystal growth process. Significant progresses in optical and scintillation properties were achieved for large size LYSO crystals after eliminating this absorption band.
The Geometry of Axisymmetric Ideal Fluid Flows with Swirl

The sectional curvature of the volume preserving diffeomorphism group of a Riemannian manifold M can give information about the stability of inviscid, incompressible fluid flows on M. We demonstrate that the submanifold of the volumorphism group of the solid flat torus generated by axisymmetric fluid flows with swirl, denoted by \(\mathcal {D}_{\mu ,E}(M)\), has positive sectional curvature in every section containing the field \(X = u(r)\partial _\theta \) iff \(\partial _r(ru^2)>0\). This is in sharp contrast to the situation on \(\mathcal {D}_{\mu }(M)\), where only Killing fields X have nonnegative sectional curvature in all sections containing it. We also show that this criterion guarantees the existence of conjugate points on \(\mathcal {D}_{\mu ,E}(M)\) along the geodesic defined by X.
Online variational inference for the hierarchical Dirichlet process

The hierarchical Dirichlet process (HDP) is a Bayesian nonparametric model that can be used to model mixed-membership data with a potentially infinite number of components. It has been applied widely in probabilistic topic modeling, where the data are documents and the components are distributions of terms that reflect recurring patterns (or “topics”) in the collection. Given a document collection, posterior inference is used to determine the number of topics needed and to characterize their distributions. One limitation of HDP analysis is that existing posterior inference algorithms require multiple passes through all the data—these algorithms are intractable for very large scale applications. We propose an online variational inference algorithm for the HDP, an algorithm that is easily applicable to massive and streaming data. Our algorithm is significantly faster than traditional inference algorithms for the HDP, and lets us analyze much larger data sets. We illustrate the approach on two large collections of text, showing improved performance over online LDA, the finite counterpart to the HDP topic model.
Treating hypertension in hemodialysis improves symptoms seemingly unrelated to volume excess

BACKGROUND Among hemodialysis patients, probing dry weight is an effective strategy for improving control of hypertension. Whether controlling hypertension improves or worsens symptoms among such patients remains unclear. The purpose of the study was to develop a tool to evaluate symptoms and examine the relationship of the change in these symptoms with blood pressure (BP) control. METHODS Among patients participating in the Hemodialysis Patients Treated with Atenolol or Lisinopril (HDPAL) randomized controlled trial, a confirmatory factor analysis (CFA) was performed to establish the relationship between symptoms and organ systems. Next, the change in symptom scores pertaining to organ systems was analyzed using a mixed model. Finally, the independent effect of lowering home BP on change in symptoms was evaluated. RESULTS Among 133 participants where symptoms were available at baseline, CFA revealed four level 1 domains: gastrointestinal symptoms, dialysis-related symptoms, cardiovascular symptoms and general symptoms. All except dialysis-related symptoms were ascribed to uremia (level 2 domain). Uremic symptoms improved over 6 months and then increased. Dialysis-related symptoms (fatigue, cramps and orthostatic dizziness) did not worsen despite lowering home BP. Probing dry weight was independently associated with an improvement in cardiovascular symptoms such as shortness of breath. CONCLUSIONS Reducing BP through the use of a strategy that includes volume control and medication improves symptoms seemingly unrelated to volume excess. In long-term hemodialysis patients, treating hypertension using home BP measurements may improve well-being.
Effect of Local Loss of Support on Foundation Design

Investigation of effects of development of small sink holes, excavation for temporary repairs, erosion by groundwater, or compaction resulting from vibrations on local subsidence beneath foundation structures; results of study for beams and slabs that span gaps in elastic subgrade; in order to simplify computations, curves have been prepared that may be used for design.
Sealed Silver-Zinc Batteries

Abstract Research and development programs have been in progress to provide design criteria for the successful operation of hermetically sealed secondary silver-zinc batteries for aerospace applications. A systematic approach was used to elucidate and optimize the important internal design factors governing cycle life and energy yield. New data are presented which establish the effects on cycle life of variation in active material ratios, electrolyte concentration, and mercury content in the zinc plate. Addition of palladium to the positive plate is shown to increase recharge capability. Data for energy yield of plate packs where total equivalent amounts of active material are distributed among several plate number combinations show that yields increase as plate thickness increases. Sealed operation was accomplished for hundreds of cycles with minor internal pressure build up by controlling the upper limit of charge voltage. Appropriate data describe the magnitude of the several effects and a photograph of cycling sealed batteries show internal pressure levels. It is concluded that sealed operation of silver-zinc batteries is practical, that substantial progress has been made in improving life, and that considerable improvement in performance is still possible.
Repair of bone-transplant fractures.

Fresh autogenous-bone transplant fractures in rabbits have the capacity to unite as early as two weeks in more than two-thirds of the animals. Some of the surface cells of the transplants appeared to survive and proliferate to produce new bone. The graft replacement occurred by creeping substitution. The transplants were well tolerated by host tissues. Graft fracture healing in fresh homogenous transplants was delayed by several weeks, and less than one-third of the fractures united. Marked absorption of the fresh homogenous implant predominated prior to ossification, if any. Fresh and frozen homogenous transplants induced a cellular inflammatory reaction similar to that described for other homogenous graft tissue. Frozen, freeze-dried, and merthiolate-preserved homogenous-bone implants produced little osteogenic stimulus in the host tissues. Graft fractures usually do not unite. These grafts were replaced very slowly, if at all, by fibrous tissue first, and then by bone. Fresh autogenous-bone transplants are far superior to any other type of bone transplant. The repair capacity of fresh autogenous grafts as measured by graft fracture healing exceeds that of fresh, frozen, freeze-dried, merthiolate-preserved homogenous grafts, or frozen and boiled autogenous grafts. Fresh homogenous grafts exhibited the next best osteogenic-repair capacity; however, the marked inflammatory incompatibility reaction to the homogenous bone may be detrimental.
Catalytic Enantioselective Functionalization of Unactivated Terminal Alkenes

Terminal alkenes are readily available functional groups which appear in α-olefins produced by the chemical industry, and they appear in the products of many contemporary synthetic reactions. While the organic transformations that apply to alkenes are amongst the most studied reactions in all of chemical synthesis, the number of reactions that apply to nonactivated terminal alkenes in a catalytic enantioselective fashion is small in number. This Minireview highlights the cases where stereocontrol in catalytic reactions of 1-alkenes is high enough to be useful for asymmetric synthesis.
On the Power of Public-Key Encryption in Secure Computation

We qualitatively separate semi-honest secure computation of nontrivial secure-function evaluation (SFE) functionalities from existence of keyagreement protocols. Technically, we show the existence of an oracle (namely, PKE-oracle) relative to which key-agreement protocols exist; but it is useless for semi-honest secure realization of symmetric 2-party (deterministic finite) SFE functionalities, i.e. any SFE which can be securely performed relative to this oracle can also be securely performed in the plain model.
Effect of Isovalent Substitution on the Structure and Properties of the Zintl Phase Solid Solution Eu7Cd4Sb8-xAsx (2 ≤ x ≤ 5).

A novel Zintl phase structure type, Eu7Cd4Sb8–xAsx (x = 2, 3, 4, and 5), with the general formula Eu7Cd4Pn8 (Pn = mixed occupancy Sb and As), was synthesized by molten tin flux reaction. Its structure was determined using single-crystal X-ray diffraction methods. This structure type is only preserved for 2 ≤ x ≤ 5 under our experimental conditions, and efforts to synthesize samples with x 5 resulted in other structure types. The mixed occupancy Sb and As can be thought of as a pseudoatom whose ideal size, in this range of Sb/As ratios, fits the structure. The title phase crystallizes in the I-centered monoclinic space group I2/m (No. 12, Z = 4) with unit cell parameters ranging as follows: a = 19.7116(17)–19.4546(13) A, b = 4.6751(4)–4.6149(3) A, c = 24.157(2)–23.871(15) A, and β = 95.8798(1)–96.016(5)°, depending on the Sb/As ratio. The structure can be described as parallel double pentagonal tubes resulting from Cd–Pn and Pn–Pn bonding. These double pentagons are formed through corner sharing...
Shear-Induced Desorption of Isolated Polymer Molecules from a Planar Wall

We use Brownian dynamics simulations with hydrodynamic interactions to reconcile the apparent contradictions in experiments on the effect of shear flow on desorption of polymers. Our simulations sh...
Allocation of licensed and unlicensed spectrum in heterogeneous networks

In order to support fast growing mobile data traffic, wireless operators have started to use multiple radio access technologies (RATs) over multiple licensed and unlicensed frequency bands. A widely used method is WiFi off-loading of cellular network traffic. A recent proposal is side-by-side deployment of Long Term Evolution (LTE) in licensed spectrum and LTE in unlicensed spectrum (LTE-U). This paper studies the spectrum allocation problem in such heterogeneous networks (HetNets). For practical reasons, the allocation is conceived to be on a relatively slow timescale. A queueing model is introduced for the unlicensed band to capture its lower spectral efficiency, reliability, and additional delay due to contention and/or listen-before-talk requirements. Under mild assumptions, the spectrum allocation problem is formulated as a bi-convex optimization problem. Solving this problem gives an effective and computationally efficient solution for both user association and spectrum allocation over multiple RATs. Simulation results show that in the heavy-traffic regime, the proposed scheme significantly outperforms both orthogonal and full-frequency-reuse allocations. In addition, the solution to the optimization problem matches the intuition that users with relatively higher traffic demand are mostly assigned to the licensed spectrum, while those with lower traffic demand and less exogenous interference from the unlicensed band are assigned to the unlicensed spectrum.
Manufacturing pathway and experimental demonstration for nanoscale fine-grained 3-D integrated circuit fabric

At Sub-20nm technologies CMOS scaling faces severe challenges primarily due to fundamental device scaling limitations, interconnection overhead and complex manufacturing. Migration to 3-D has been long sought as a possible pathway to continue scaling; however, CMOS's intrinsic requirements are not compatible for fine-grained 3-D integration. In [1], we proposed a truly fine-grained 3-D integrated circuit fabric called Skybridge that solves nanoscale challenges and achieves orders of magnitude benefits over CMOS. In Skybridge, device, circuit, connectivity, thermal management and manufacturing issues are addressed in an integrated 3-D compatible manner. At the core of Skybridge's assembly are uniform vertical nanowires, which are functionalized with architected features for fabric integration. All active components are created primarily using sequential material deposition steps on these nanowires. Lithography and doping precision requirements are significantly reduced, and are primarily required in early stages. In this paper, we discuss manufacturing aspects of Skybridge fabric; we introduce Skybridge's manufacturing pathway and show experimental demonstrations of key process steps.
Forging a West that Works: An Invitation to the Radical Center

Forging a West that Works: An Invitation to the Radical Center DOI:10.2458/azu_rangelands_v58i6_capelli
No Shot: US Vaccine Prices And Shortages

In 2004 an Institute of Medicine report warned of vaccine shortages, raising concerns about disease outbreaks. More than a decade later, we looked for progress in reducing vaccine shortages. We analyzed data on vaccine sales and shortages reported by practitioners and patients to the Food and Drug Administration and the American Society of Health-System Pharmacists in the period 2004-13. We found that the number of annual vaccine shortages peaked in 2007, when there were shortages of seven vaccines; there were only two shortages in 2013. There were no shortages of vaccines with a mean price per dose greater than $75 during the study period. Furthermore, we found that a 10 percent increase in price was associated with a nearly 1 percent decrease in the probability of a shortage. Government payers should carefully consider the benefits of averting shortages when evaluating prices for vaccines, including older vaccines whose prices have been subject to congressional price caps.
Hydrodynamic coupling of particle inclusions embedded in curved lipid bilayer membranes

We develop theory and computational methods to investigate particle inclusions embedded within curved lipid bilayer membranes. We consider the case of spherical lipid vesicles where inclusion particles are coupled through (i) intramembrane hydrodynamics, (ii) traction stresses with the external and trapped solvent fluid, and (iii) intermonolayer slip between the two leaflets of the bilayer. We investigate relative to flat membranes how the membrane curvature and topology augment hydrodynamic responses. We show how both the translational and rotational mobility of protein inclusions are effected by the membrane curvature, ratio of intramembrane viscosity to solvent viscosity, and intermonolayer slip. For general investigations of many-particle dynamics, we also discuss how our approaches can be used to treat the collective diffusion and hydrodynamic coupling within spherical bilayers.
Interaction-based invention: designing novel devices from first principles

An inventor who is skilled at constructing innovative designs is distinguished, not just by the first principles he knows, but by the way he uses these principles and how he focusses the search for novel devices among an overwhelming space of possibilities. We propose that an appropriate focus for design is the network of qualitative interactions between quantities, (called an interaction topology), used by a device to achieve its desired behavior. We present an approach, called interaction-based invention, which views design as a process of building interaction topologies -- in this paper directly from first principles. The program Ibis, which embodies this approach, designs simple hydro-mechanical regulators, analogous to devices that were fundamental to the development of feedback control theory.
Some Physical Properties of Isoprene

Abstract Isoprene (2-methyl-1,3-butadiene) has been for many years a substance of very considerable interest in the study of rubber, since it has been shown to be the fundamental unit in the constitution of the rubber hydrocarbon. Isoprene polymerizes to form a product which is chemically more closely related to natural rubber than any other synthetic product. Furthermore, the destructive distillation of natural rubber yields as its two major products isoprene and dipentene (dl-1-methyl-4-isopropenyl-1-cyclohexene) in amounts far exceeding those of any other constituents. Aside from its relation to rubber, isoprene is of interest, because it is thought to be the basic substance in the natural synthesis of terpenes and to play an important role in the formation of plant cells. An investigation of the chemical thermodynamics of rubber now in progress at the Cryogenic Laboratory of this Bureau includes a study of isoprene and its relationship to rubber. Measurements of heat capacity and heat of combustion ar...
Stereospecific nickel-catalyzed cross-coupling reactions of benzylic ethers and esters.

ConspectusThis Account presents the development of a suite of stereospecific alkyl–alkyl cross-coupling reactions employing nickel catalysts. Our reactions complement related nickel-catalyzed stereoconvergent cross-coupling reactions from a stereochemical and mechanistic perspective. Most reactions of alkyl electrophiles with low-valent nickel complexes proceed through alkyl radicals and thus are stereoablative; the correct enantioselective catalyst can favor the formation of one enantiomer. Our reactions, in contrast, are stereospecific. Enantioenriched ethers and esters are cleanly converted to cross-coupled products with high stereochemical fidelity. While mechanistic details are still to be refined, our results are consistent with a polar, two-electron oxidative addition that avoids the formation of radical intermediates. This reactivity is unusual for a first-row transition metal.The cross-coupling reactions engage a range of benzylic ethers and esters, including methyl ethers, tetrahydropyrans, tetr...
Solving hybrid influence diagrams with deterministic variables

We describe a framework and an algorithm for solving hybrid influence diagrams with discrete, continuous, and deterministic chance variables, and discrete and continuous decision variables. A continuous chance variable in an influence diagram is said to be deterministic if its conditional distributions have zero variances. The solution algorithm is an extension of Shenoy's fusion algorithm for discrete influence diagrams. We describe an extended Shenoy-Shafer architecture for propagation of discrete, continuous, and utility potentials in hybrid influence diagrams that include deterministic chance variables. The algorithm and framework are illustrated by solving two small examples.
The Effects of the Works Progress Administration's Anti-Malaria Programs in Georgia 1932–1947

Abstract From 1900 to 1950, malaria rates declined rapidly in the southeast United States. At its peak, malaria infected over 30% of the population. Malaria declined over the period for several reasons: improvements in public infrastructure; development of new insecticides; improvements in agriculture that promoted drainage; increases in incomes; and changes in migration patterns. This paper focuses on public works constructed by the Works Progress Administration (WPA) during the 1930s and subsequent interventions during the 1940s. To estimate the relationship between these malaria programs and malaria rates, I construct a panel of annual county level malaria rates in Georgia from 1932 to 1947. Between 1932 and 1940 the malaria rate in counties that received WPA malaria projects fell from 25.9 deaths per 100,000 to 5.3 deaths per 100,000. The empirical estimates suggest that WPA malaria projects led to 9.1 fewer deaths per 100,000 or roughly 44% of the observed decline in treated counties. Additional public works constructed by the MCWA during World War II, and the introduction of DDT after 1945 completely eliminated malaria in Georgia by 1947.
Farmers’ Willingness and Expected Economic Benefit to Adopt BMPs: an Application of Multivariate Imputation by Chained Equation Method

Water Quality Trading (WQT) programs may offer farmers compensation to adopt Best Management Practices (BMPs). We conducted a survey of farmers in the Kentucky River watershed from 2011 to 2012. With respect to the five types of BMPs considered in the survey, about 20% of respondents did not indicate how much they will adopt. Missing responses are common for surveys on farming decisions. We compare three methods to handle the missing data: deleting the observations with missing value, mean imputation, and Multivariate Imputation by Chained Equation (MICE). Following these missing data treatments, we estimate the factors affecting how much farmers may engage in BMPs using Tobit or Poisson model. The results show that increasing the compensation for using BMPs is more likely to encourage farmers to adopt riparian buffers. In addition, land area, percentage of household income from farming, percentage of total household income reinvested back to farm, and current experience of BMPs will affect BMP adoption. The results obtained after using the MICE are more promising and reasonable than using the deletion or the mean imputation method. Implications are discussed for farmers’ BMP adoptions under WQT while missing observations are present.
Theory and Measurement in Social Capital Research

In 1988, James Coleman observed that “social capital is defined by its function. It is not a single entity but a variety of different entities, with two elements in common: they all consist of some aspect of social structures, and they facilitate certain actions of actors-whether persons or corporate actors-within the structure.” If one looks at the state of social capital research, it is clear that this is truer than ever before. This paper seeks to help researchers overcome the major challenges of social capital research, namely, measuring a concept that is notoriously difficult for measurement and choosing among the exhaustive list of direct, casual and consequential measures. It does so by arguing for a typology of social capital that considers five major types of social capital and then reviewing a diverse selection of data available from national surveys. This provides a resource for scholars wishing to pursue large-scale social capital research. Additionally, it draws six lessons from this body of theory and measurement to improve the study of social capital.
QoS Differentiated Adaptive Scheduled Optical Burst Switching for Grid Networks

This paper presents the QoS differentiated Adaptive Scheduled Optical Burst Switching (QAS-OBS) paradigm that efficiently supports dynamic grid applications. (QAS-OBS) paradigm enables differentiated-services optical burst switching via two-way reservation and adaptive QoS control in distribute wavelength-routed networks. Based on the network loading status, the edge nodes dynamically optimize per-class lightpath reservation control to provide proportional QoS differentiation, while maximizing the overall network throughput. Unlike existing QoS control schemes that require special core network to support burst switching and QoS control, QAS-OBS pushes all the complexity of burst switching and QoS control to the edge nodes, so that the core network design is maximally simplified. Simulation results evaluate the performance of QAS-OBS and verified the proposed control schemes could provide proportional QoS control while maximizing the overall network throughput.
(3+2)-Cycloaddition Reactions of Oxyallyl Cations

The (3+2)-cycloaddition reaction involving oxyallyl cations has proven to be a versatile and efficient approach for the construction of five-membered carbo- and heterocycles, which are prevalent frameworks in natural products and pharmaceuticals. The following article will provide a brief summary of recent disclosures on this process featuring chemo-, regio- and diastereoselective oxyallyl cycloadditions with both electron-rich and electron-deficient 2π partners.
Theoretical Investigation of the Second and Third Order Nonlinear Optical Properties of Some Fused Heterocyclic Aromatic Compounds

We report herein the results of coupled perturbed Hartree-Fock (CPHF) ab initio extended basis set calculations on the geometric structures, dipole moments, static first-order (α), second-order (β), and third-order polarizabilities (λ) of a series of fused heterocyclic aromatic compounds based on quinoline. The effects of the presence/absence of the heteroatom as well as the introduction of other substituents at various positions in the ring system on these molecular properties are described. The effect of the presence of N-oxide is also examined. Suggestions for the design of heterocyclic systems with enhanced polarizabilities are made.
Spin Hall effect in a magnetic field

When a spin-polarized current is injected into a non-magnetic semiconductor, a transverse electric field known as Hall voltage is generated. By using a macroscopic diffusion equation, we derive the Hall voltage in the presence of both spin current and magnetic field. Novel features such as oscillating Hall signals as a function of the magnetic field and geometrical dependence of Hall signals are predicted.
Efficient and Scalable Synthesis of 4-Carboxy-Pennsylvania Green Methyl Ester: A Hydrophobic Building Block for Fluorescent Molecular Probes.

Fluorinated fluorophores are valuable tools for studies of biological systems. However, amine-reactive single-isomer derivatives of these compounds are often very expensive. To provide an inexpensive alternative, we developed a practical synthesis of 4-carboxy-Pennsylvania Green methyl ester. Derivatives of this hydrophobic fluorinated fluorophore, a hybrid of the dyes Oregon Green and Tokyo Green, are often cell-permeable, enabling labeling of intracellular targets and components. Moreover, the low pK a of Pennsylvania Green (4.8) confers bright fluorescence in acidic cellular compartments, such as endosomes, enhancing its utility in chemical biology investigations. To improve access to the key intermediate 2,7-difluoro-3,6-dihydroxyxanthen-9-one, we subjected bis(2,4,5-trifluorophenyl)methanone to iterative nucleophilic aromatic substitution by hydroxide on scales in excess of 40 grams. The key intermediate was used to prepare over 15 grams of pure 4-carboxy-Pennsylvania green methyl ester in 28% overall yield without the use of chromatography. This compound can be converted into the amine-reactive N-hydroxysuccinimidyl ester in essentially quantitative yield for the synthesis of a wide variety of fluorescent molecular probes.
Teams, Leaders, and Performance Measures*

This paper studies the effect of leadership on the ability to promote cooperation in teams through the performance measurement system. Performance measurement of teams can promote cooperation by rewarding team success, or can emphasize and reward individual success, by promoting competition via relative performance evaluation. In order to highlight the tradeoff between individual and group incentives, I consider the impact of leadership, where one agent with private productivity information acts as a leader and partially signals his information via his action to the agent who is an uninformed follower. With symmetric, privately informed agents, promoting cooperation with group incentives is more costly than promoting competition with individual incentives. The team is more likely to be successful than individuals and agents rewarded based on the team output earn more informational rents than agents rewarded for individual performance. With one informed agent, group incentives that promote cooperation can be preferred for both agents but only with signaling between the leader and follower. With no signaling, group incentives are too costly for the informed agent, but may be preferred for the uninformed agent. Uninformed agents earn fewer rents, but are productively inefficient; with signaling, the follower’s productive efficiency improves, lowering the cost. Also, because of the effect of the follower’s action on the leader’s incentives, the leader’s incentives are decreased, resulting in a lower payment. The results suggest that leadership can not only improve productive efficiencies via information sharing, but can reduce information rents, allowing for the use of cooperative performance measures.
Synthesis of Propargylic and Allenic Carbamates via the C–H Amination of Alkynes

Propargylic amines are important intermediates for the synthesis of nitrogen-containing heterocycles. The insertion of a nitrene into a propargylic C–H bond has not been explored, despite the attention directed toward the Rh-catalyzed amination of other types of C–H bonds. In this communication, the conversion of a series of homopropargylic carbamates to propargylic carbamates and aminated allenes is described.
Development of a used fuel cladding damage model incorporating circumferential and radial hydride responses

Abstract At the completion of the fuel drying process, used fuel Zry4 cladding typically exhibits a significant population of δ -hydride inclusions. These inclusions are in the form of small platelets that are generally oriented both circumferentially and radially within the cladding material. There is concern that radially-oriented hydride inclusions may weaken the cladding material and lead to issues during used fuel storage and transportation processes. A high fidelity model of the mechanical behavior of hydrides has utility in both designing fuel cladding to be more resistant to this hydride-induced weakening and also in suggesting modifications to drying, storage, and transport operations to reduce the impact of hydride formation and/or the avoidance of loading scenarios that could overly stress the radial inclusions. We develop a mechanical model for the Zry4-hydride system that, given a particular morphology of hydride inclusions, allows the calculation of the response of the hydrided cladding under various loading scenarios. The model treats the Zry4 matrix material as J 2 elastoplastic, and treats the hydrides as platelets oriented in predefined directions (e.g., circumferentially and radially). The model is hosted by the Albany analysis framework, where a finite element approximation of the weak form of the cladding boundary value problem is solved using a preconditioned Newton–Krylov approach. Instead of forming the required system Jacobian operator directly or approximating its action with a differencing operation, Albany leverages the Trilinos Sacado package to form the Jacobian via automatic differentiation. We present results that describe the performance of the model in comparison with as-fabricated Zry4 as well as HB Robinson fuel cladding. Further, we also present performance results that demonstrate the efficacy of the overall solution method employed to host the model.
DESAFÍOS PARA EL ORDENAMIENTO JURÍDICO CHILENO ANTE EL CRECIMIENTO SOSTENIDO DE LOS FLUJOS MIGRATORIOS

Este trabajo realiza un analisis critico de algunos elementos configuradores de la legislacion chilena de inmigracion, especificamente aquellos relacionados con sus fundamentos y con la proteccion de los derechos de las personas inmigrantes. Luego de constatar los importantes cambios en los flujos migratorios hacia Chile, se revisan recientes decisiones del Tribunal Constitucional y de la Corte Suprema, asi como del proyecto de nueva ley de inmigracion, actualmente en tramite. El articulo considera como los bajos estandares en materia de proteccion de derechos de las personas migrantes en Chile han sido constatados por organismos internacionales, para concluir en la necesidad de revisar integramente la configuracion legislativa del estatuto juridico del inmigrante.
Effects of Bearings and Housing on Mode Localization of a Nearly Cyclic Symmetric System

This technical brief is to study how flexible bearings and housing affect mode localization of a nearly cyclic symmetric system with mistuning. This study is conducted via finite-element analyses and deductive reasoning. A reference system studied is a bladed disk with two groups of 24 localized modes. When bearings and housing are introduced into the reference system, their presence changes natural frequencies, mode shapes, and the number of the localized modes. Moreover, the mistuning causes bearing forces to surge for all the localized modes. A deductive reasoning based on the existing literature supports the observation from the finite-element analyses.
Power it up: Strengthening the electricity sector to improve efficiency and support economic activity

Poor performance of the electricity sector remains a drag to economic efficiency and a bottleneck to economic activity in many low-income countries. This paper proposes a number of models that account for different equilibria (some better, some worse) of the electricity sector. They show how policy choices (affecting insolvency prospects or related to rules for electricity dispatching or tariff setting), stochastic generation costs, and initial conditions, affect investment in generation and electricity supply. They also show how credible (non-credible) promises of stronger enforcement to reduce theft result in larger (smaller) electricity supply, lower (higher) government subsidies, and lower (higher) tariffs and distribution losses, which in turn affect economic activity. To illustrate these findings, the paper reviews the experience of Haiti, a country stuck in a bad equilibrium of insufficient supply, high prices, and electricity theft; and that of Nicaragua, which is gradually transitioning to a better equilibrium.
The splenic injury outcomes trial: An American Association for the Surgery of Trauma multi-institutional study.

BACKGROUNDDelayed splenic hemorrhage after nonoperative management (NOM) of blunt splenic injury (BSI) is a feared complication, particularly in the outpatient setting. Significant resources, including angiography (ANGIO), are used in an effort to prevent delayed splenectomy (DS). No prospective, lo
Fractionation techniques in process biotechnology

The application of fractionation techniques to protein purification at a process or industrial scale is reviewed. The principles of various chromatographic separations are described and the choice and selection of available matrices discussed. Gel filtration, ion-exchange hydrophobic interaction and affinity chromatographic techniques can all operate at process scale. HPLC is particularly suitable for process development and scale up without loss of efficiency. Magnetic separation, solvent partitioning and electrophoresis also offer potential for process scale operation. Recent developments also include improved matrices and the application of genetic engineering techniques to design proteins for efficient separation.
Osteoporosis in men.

Although early studies of the epidemiology of fractures revealed that the classical age-related increase seen in women is evident in men as well, only in the last few years has it been recognized that the problem of osteoporosis in men represents an important public health issue. 88,110,114 Osteoporosis in men presents a unique array of scientific challenges and opportunities and deserves the same vigorous evaluation applied to postmenopausal osteoporosis.