cssi/SciSciGPT-SciSciNet huggingface dataset:
The enhancement of CO hydrogenation on rhodium by TiOx overlayers

Abstract The kinetics of CO hydrogenation at atmospheric pressure over a polycrystalline Rh foil with titania deposits were characterized with respect to the surface composition. The titania overlayers (TiO x , x ~ 1.9) were prepared by titanium evaporation under ultrahigh vacuum with subsequent oxidation. Coverages were determined by Auger electron spectroscopy (AES). A sharp maximum in methanation activity, relative to the clean Rh surface, was observed with coverage. A threefold enhancement in activity was found for a TiO x coverage of 0.15 of a monolayer. The increase in rate at low coverages was accompanied by a higher selectivity toward olefins (10% → 31%), a lower activation energy (24.4 → 16.8 kcal/mol), a higher H 2 reaction order (1.0 → 2.6), and a higher CO reaction order (−1.0 → −0.3). The kinetic parameters for olefin production were noticeably different than those for paraffin production as well. The dependence of the activity on TiO x coverage has been modeled through a Monte Carlo simulation assuming the existence of sites of high activity at the oxide-metal interface. This model is consistent with the premise of Ti 3+ participation in the dissociation of CO.
Protuberances in a Turbulent Thermal Boundary Layer

Recent efforts to evaluate the effects of isolated protuberances within velocity and thermal boundary layers have been performed using transient heat transfer approaches. While these approaches provide accurate and highly resolved measurements of surface flux, measuring the state of the thermal boundary-layer during transient tests with high spatial resolution presents several challenges. As such, the heat transfer enhancement evaluated during transient tests are presently correlated to a Reynolds number based either on the distance from the leading edge or on the momentum thickness. Heat flux and temperature variations along the surface of a turbine blade may cause significant differences between the shapes and sizes of the velocity and thermal boundary layer profiles. Therefore, correlations are needed which relate the states of both the velocity and thermal boundary layers to protuberance and roughness distribution heat transfer. In this study, a series of three experiments are performed for various freestream velocities to investigate the local temperature details of protuberances interacting with thermal boundary layers. The experimental measurements are performed using isolated protuberances of varying thermal conductivity on a steadily-heated, constant flux flat plate. In the first experiment, detailed surface temperature maps are recorded using infrared thermography. In the second experiment, the unperturbed velocity profile over the plate without heating is measured using hot-wire anemometry. Finally, the thermal boundary layer over the steadily heated plate is measured using a thermocouple probe. Because of the constant flux experimental configuration, the protuberances provide negligible heat flux augmentation. Consequently, the variation in protuberance temperature is investigated using the velocity boundary layer parameters, the thermal boundary layer parameters, and the local fluid temperature at the protuberance apices. A comparison of results using plastic and steel protuberances illuminates the importance of the shape of the thermal and velocity boundary layers in determining the minimum protuberance temperatures.Copyright © 2011 by ASME
Three-dimensional position determination from motion

The analysis of sequences of images over time provides a means of extracting meaningful information which is used to compute and track the three-dimensional position of a moving object This paper describes an application in which sensory feedback based on time-varying camera images is used to provide position information to a manipulator control system. The system operates in a real-time environment and provides updated information at a rate which permits intelligent trajectory planning by the control system.
Highly Enantioselective Syntheses of Functionalized α-Methylene-γ-butyrolactones via Rh(I)-catalyzed Intramolecular Alder Ene Reaction: Application to Formal Synthesis of (+)-Pilocarpine

A highly enantioselective Rh(I)-catalyzed intramolecular Alder ene reaction has been developed. The desired products, 3-vinyl, vinyl acetate, and vinyl ether-substitued α-methylene-γ-butyrolactones were formed in high yields. Aldehydes were produced with the formation of γ-lactones when alcohols were substituted at allylic position in the substrates. All reactions with listed substrates proceeded in over 99% ee. A formal synthesis of (+)-pilocarpine is an excellent example to demonstrate the synthetic utility of this methodology.
CATALYTIC INTRAMOLECULAR HYDROAMINATION OF HINDERED ALKENES USING ORGANOLANTHANIDE COMPLEXES

The intramolecular hydroamination of hindered alkenes has been developed as a versatile route to heterocyclic systems. The current process utilizes the unhindered catalyst system [CpTMS2LnMe]2 (Ln = Sm, Nd) to effect the cyclization of hindered amino olefins, providing products containing quaternary centers. The process tolerates a wide variety of substitution patterns, allowing the construction of monocyclic as well as fused and bridged bicyclic heterocycles. Two experimental procedures were employed in this study: one without solvent, minimizing waste streams, the other in deuterated solvents, allowing NMR monitoring of the reaction. The yield of each reaction was high, with NMR analysis of the reactions in progress showing clean conversion from starting material to a single product in most cases.
QBE/PC: the design of an integrated software system for a personal computer

Integrated software has become rather popular in recent years. After the spreadsheet found wide acceptance among application users, many vendors rushed to integrate several well-defined business application tasks within a spreadsheet environment. Such systems, however, are limited in that they cannot replace a conventional database. Businesses must keep data in a formal database to maintain data consistency and facilitate sharing. This paper describes the design and implementation of an integrated software system which captures the ease-of-use of many of the current integrated systems, and also provides a relational database for common data storage, allowing for data sharing among several integrated business applications. In addition, the system provides an unusually powerful visual interface which can be used to build custom applications without the need for traditional programming.
The Lockerbie disaster and other aircraft breakups in midair

This is a review of the experiences and activities of various specialty groups that constituted the organization developed to investigate the Lockerbie air disaster. Circumstances surrounding other aircraft midair breakup crashes are also discussed.
Application of bidirectional ellipsometry to the characterization of roughness and defects in dielectric layers

The polarization of light scattered into directions out of the plane of incidence is calculated for microroughness, defects, or particles in or near a dielectric film on a substrate. The theories for microroughness and Rayleigh scatter in the presence of dielectric films are reviewed, and a method for calculating the Mueller matrix for scatter from multiple sources is described. The situation of a 1 micrometers thick layer of SiO2 on a silicon substrate illuminated by a p-polarized 633 nm light at a 60 degree(s) angle of incidence is used to demonstrate the model calculations. The polarization of scattered light is calculated for scatter from roughness at each of the interfaces separately and roughness of both interfaces when those roughnesses are correlated and uncorrelated. The scatter from a single Rayleigh defect is considered as a function of the position of that defect within the dielectric film, and the scatter from a random distribution of Rayleigh defects in the layer is calculated. The capability of distinguishing amongst different scattering sources is discussed.
The X-Ray Polarization Signature of Quiescent Magnetars: Effect of Magnetospheric Scattering and Vacuum Polarization

In the magnetar model, the quiescent non-thermal soft X-ray emission from anomalous X-ray pulsars and soft gamma repeaters is thought to arise from resonant Comptonization of thermal photons by charges moving in a twisted magnetosphere. Robust inference of physical quantities from observations is difficult, because the process depends strongly on geometry, and current understanding of the magnetosphere is not very deep. The polarization of soft X-ray photons is an independent source of information, and its magnetospheric imprint remains only partially explored. In this paper, we calculate how resonant cyclotron scattering would modify the observed polarization signal relative to the surface emission, using a multidimensional Monte Carlo radiative transfer code that accounts for the gradual coupling of polarization eigenmodes as photons leave the magnetosphere. We employ a globally twisted, self-similar, force-free magnetosphere with a power-law momentum distribution, assume a blackbody spectrum for the seed photons, account for general relativistic light deflection close to the star, and assume that vacuum polarization dominates the dielectric properties of the magnetosphere. The latter is a good approximation if the pair multiplicity is not much larger than unity. Phase-averaged polarimetry is able to provide a clear signature of the magnetospheric reprocessing of thermal photons and to constrain mechanisms generating the thermal emission. Phase-resolved polarimetry, in addition, can characterize the spatial extent and magnitude of the magnetospheric twist angle at ~100 stellar radii, and discern between uni- or bidirectional particle energy distributions, almost independently of every other parameter in the system. We discuss prospects for detectability with the Gravity and Extreme Magnetism (GEMS) mission.
Criticality of Counterexamples to Toroidal Edge-Hamiltonicity

A well-known conjecture of Grunbaum and Nash-Williams proposes that $$4$$4-connected toroidal graphs are Hamiltonian. The corresponding results for $$4$$4-connected planar and projective-planar graphs were proved by Tutte and by Thomas and Yu, respectively, using induction arguments that proved a stronger result, that every edge is on a Hamilton cycle. However, this stronger property does not hold for $$4$$4-connected toroidal graphs: Thomassen constructed counterexamples. Thus, the standard inductive approach will not work for the torus. One possible way to modify it is by characterizing the situations where some edge is not on a Hamilton cycle. We provide a contribution in this direction, by showing that the obvious generalizations of Thomassen's counterexamples are critical in a certain sense.
A concise synthesis of quinazolinone TGF-β RI inhibitor through one-pot three-component Suzuki-Miyaura/etherification and imidate-amide rearrangement reactions

Abstract A simple and efficient synthesis of dihydropyrrolopyrazole boronic acid intermediate ( 5 ) has been developed. Utilization of a three-component Suzuki–Miyaura/etherification with microwave heating led to advanced compound 11 in high yield and with easy purification. Reaction of compound 11 with methanesulfonyl chloride at room temperature furnished the 1,3 O – N rearranged product ( 12 ), which is postulated to proceed via an intramolecular mechanism. The outlined synthesis provides a highly efficient and high-yielding route that is amenable to rapid analog synthesis.
THE CASE FOR CORPORATE MANAGEMENT OF FOREIGN EXCHANGE RISK

* The objective of this paper is to present the case for corporate management of foreign exchange risk. The arguments that oppose hedging at the level of the firm can be summed up as follows: Foreign exchange risk does not exist; even if it exists, it need not be hedged; even if it is to be hedged, corporations need not hedge it. In support of the above reasoning, one or more of the following arguments are advanced. 1. The Purchasing Power Parity (PPP) theorem implies compensating changes in price levels and exchange rates; hence, there is no exchange risk. 2. The Capital Asset Pricing Model (CAPM) purportedly suggests that it makes no difference whether exchange risk is managed separately or passed along to the capital market; hence, even if exchange risk exists, it need not be hedged. 3. The Modigliani-Miller (MM) theorem implies
Institutional Owners and Corporate Social Performance

In this study, we hypothesize that institutions invest more heavily in companies with strong corporate social performance. Analysis indicated a significant, positive relationship between social per...
Time-optimal tree computations on sparse meshes

The main goal of this work is to fathom the suitability of the mesh with multiple broadcasting architecture (MMB) for some treerelated computations. We view our contribution at two levels: on the one hand we exhibit time lower bounds for a number of tree-related problems both on the CREW-PRAM and on the MMB. On the other hand, we show that these lower bounds are tight by exhibiting time-optimal tree algorithms on the MMB. Specifically, we show that the task of encoding and/or decoding n-node binary and ordered trees cannot be solved faster than Ω(log n) time even if the MMB has an infinite number of processors. We then go on to show that this lower bound is tight. We also show that the task of reconstructing n-node binary trees from their traversais can be performed in O(1) time on the same architecture. Our algorithms rely on novel time-optimal algorithms on sequences of parentheses that we also develop.
How virtual teams use their virtual workspace to coordinate knowledge

Virtual team members increasingly rely on virtual workspace tools to coordinate knowledge that each individual brings to the team. How the use of these tools affects knowledge coordination within virtual teams is not well understood. We distinguish between tools as features and the use of the virtual workspace as providing affordances for behaviors. Using situational awareness theory, we hypothesized two affordances of virtual workspaces that facilitate knowledge coordination. Using trading zone theory, we hypothesized two forms of trading zones created by features of virtual workspaces and the impact of these trading zones on the creation of affordances for team members. Members of 54 teams were asked about the affordances of the virtual workspace, and team leaders were asked about specific tools provided to the team. Our hypothesized model was supported: the different forms of trading zones were differentially related to the different affordances and on affordances were related to knowledge coordination satisfaction. Theoretical implications focus on the distinction between features and affordances and on the identification of specific features that affect specific affordances. Practical implications for managers and engineers supporting virtual teams include the utility of becoming knowledgeable about different forms of trading zones that virtual workspaces can provide and understanding the relationship between trading zones and different affordances.
Tin mediated Barbier type allylation in ionic liquids

Abstract The Barbier type allylation of carbonyl compounds is a useful organic transformation as the resultant homoallylic alcohols are important building blocks for many biologically active molecules. Tin mediated Barbier allylation of different carbonyl compounds in room temperature ionic liquid, [BMIM][BF 4 ] afforded the corresponding homoallylic alcohols in good to excellent yields. The ionic liquid was successfully recycled and reused in allylation reactions.
Warming of the Eurasian Landmass Is Making the Arabian Sea More Productive

The recent trend of declining winter and spring snow cover over Eurasia is causing a land-ocean thermal gradient that is particularly favorable to stronger southwest (summer) monsoon winds. Since 1997, sea surface winds have been strengthening over the western Arabian Sea. This escalation in the intensity of summer monsoon winds, accompanied by enhanced upwelling and an increase of more than 350% in average summertime phytoplankton biomass along the coast and over 300% offshore, raises the possibility that the current warming trend of the Eurasian landmass is making the Arabian Sea more productive.
A Convenient, Highly Efficient One-Pot Preparation of Peracetylated Glycals From Reducing Sugars

ABSTRACT A convenient, highly efficient, one-pot, three-step procedure has been developed for the synthesis of peracetylated glycal derivatives from various reducing sugars including D-glucose, D-galactose, L-rhamnose, L-arabinose, D-maltose, D-lactose, and maltotriose. This procedure involves peracetylation of the reducing sugars with acetic anhydride and HBr/acetic acid followed by the transformation of the anomeric acetates to the corresponding bromides with additional HBr/acetic acid and finally reductive elimination of the 1-bromo and 2-acetoxy groups with Zn/CuSO4·5H2O in acetic acid/water containing sodium acetate. The overall yields of purified peracetylated glycals from the corresponding sugars range from 50 - 98%. Fax/Tel #: 1-313-764-7371; E-mail: koreeda@Chem.LSA.UMich.Edu
Stellar Outflows Driven by Magnetized Wide-Angle Winds

We present two-dimensional, cylindrically symmetric simulations of hydrodynamic and magnetohydrodynamic (MHD) wide-angle winds interacting with a collapsing environment. These simulations have direct relevance to young stellar objects. The results may also be of use in the study of collimated outflows from proto-planetary and planetary nebulae. We study a range of wind configurations consistent with asymptotic MHD wind collimation. The degree of collimation is parameterized by the ratio of the wind density at the pole to that of the equator. We find that a toroidal magnetic field can have a significant influence on the resulting outflow, giving rise to a very dense, jetlike flow in the postshock region. The properties of the flow in this region are similar to the asymptotic state of a collimated MHD wind. We conclude that wide-angle MHD winds are quite likely capable of driving molecular outflows. Because of difficulty in treating MHD winds ab initio in simulations, we choose magnetic field strengths in the wind consistent with slow magnetic rotators. While MHD-launched winds will be in the fast rotator regime, we discuss how our results, which rely on toroidal pinch effects, will hold for stronger field strengths.
Risk analysis in the 1980's

The application of scientific procedures to the study and evaluation of information and communications systems risks is still in its infancy. Hopefully, before the end of this decade we will see major breakthroughs both in improved techniques and greater utilization of Risk Analysis procedures by computer users. On the other hand Risk Analysis (also sometimes called Threat or Vulnerability Analysis) has real merit even by todays standards. The problem is that many organizations have still to be convinced as to its potential.
Low-Energy Universality in Atomic and Nuclear Physics

An effective field theory developed for systems interacting through short-range interactions can be applied to systems of cold atoms with a large scattering length and to nucleons at low energies. It is therefore the ideal tool to analyze the universal properties associated with the Efimov effect in three- and four-body systems. In this progress report, we will discuss recent results obtained within this framework and report on progress regarding the inclusion of higher order corrections associated with the finite range of the underlying interaction.
Variable Selection for Nonparametric Gaussian Process Priors: Models and Computational Strategies

This paper presents a unified treatment of Gaussian process models that extends to data from the exponential dispersion family and to survival data. Our specific interest is in the analysis of data sets with predictors that have an a priori unknown form of possibly nonlinear associations to the response. The modeling approach we describe incorporates Gaussian processes in a generalized linear model framework to obtain a class of nonparametric regression models where the covariance matrix depends on the predictors. We consider, in particular, continuous, categorical and count responses. We also look into models that account for survival outcomes. We explore alternative covariance formulations for the Gaussian process prior and demonstrate the flexibility of the construction. Next, we focus on the important problem of selecting variables from the set of possible predictors and describe a general framework that employs mixture priors. We compare alternative MCMC strategies for posterior inference and achieve a computationally efficient and practical approach. We demonstrate performances on simulated and benchmark data sets.
Gleason score 7 prostate cancer on needle biopsy: relation of primary pattern 3 or 4 to pathological stage and progression after radical prostatectomy

Purpose: There have been only a few contradictory publications assessing whether Gleason score 4 + 3 = 7 has a worse prognosis than 3 + 4 = 7 on biopsy material in predicting pathological stage and biochemical recurrence. Older studies predated the use of the modified Gleason grading system established in 2005.Materials and Methods: We retrospectively studied 1,791 cases of Gleason score 7 on prostatic biopsy to determine whether the breakdown of Gleason score 7 into 3 + 4 vs 4 + 3 has prognostic significance in the modern era.Results: There was no difference in patient age, preoperative serum prostate specific antigen, maximum tumor percent per core or the number of positive cores between Gleason score 3 + 4 = 7 and Gleason score 4 + 3 = 7. Gleason score 4 + 3 = 7 showed an overall correlation with pathological stage (organ confined, focal extraprostatic extension, nonfocal extraprostatic extension, seminal vesicle invasion/lymph node metastases, p = 0.005). On multivariate analysis Gleason score 4 + 3 =...
Undirected connectivity of sparse Yao graphs

Given a finite set S of points in the plane and a real value d > 0, the d--radius disk graph Gd contains all edges connecting pairs of points in S that are within distance d of each other. For a given graph G with vertex set S, the Yao subgraph Yk[G] with integer parameter k > 0 contains, for each point p ∈ S, a shortest edge pq ∈ G (if any) in each of the k sectors defined by k equally-spaced rays with origin p. Motivated by communication issues in mobile networks with directional antennas, we study the connectivity properties of Yk[Gd], for small values of k and d. In particular, we derive lower and upper bounds on the minimum radius d that renders Yk[Gd] connected, relative to the unit radius assumed to render Gd connected. We show that d = [EQUATION] is necessary and sufficient for the connectivity of Y4[Gd]. We also show that, for d ≤ 5 − 2/3 [EQUATION], the graph Y3[Gd] can be disconnected, but Y3[G2/[EQUATION]] is always connected. Finally, we show that Y2[Gd] can be disconnected, for any d ≥ 1.
CHANGES IN SOIL PHYSICAL CHARACTERISTICS DURING TRANSITION FROM INTENSIVE TILLAGE TO DIRECT SEEDING

Converting from intensive tillage to no–till systems often increases soil strength, but the long–term impact of no–till on soil strength is not fully understood. Soil strength (evaluated with a hand–held cone penetrometer) and soil water content were evaluated in the top 30 cm of a replicated wheat/fallow rotation in a Pacific Northwest silt loam (coarse–silty, mixed, mesic, typic Haploxeroll). Soil water content was significantly lower in the no–till plots than in intensive tillage plots, which required a correction to remove the impact of soil water on penetrometer resistance. A regression equation was developed to adjust cone index values for soil water content. Comparisons of cone penetration resistance, adjusted for soil water, were made among intensive tillage, first–year no–till, and 17–year no–till. First–year no–till soil was resistant to penetration, but after 17 years of no–till the soil strength was lower and approached tilled conditions. Cone index values just below the plow layer (18 cm) increased from 2 to 3 fold the first year of no–till, but after 17 years of no–till the cone index values were not statistically different between no–till and intensive tillage below the tillage layer. This research demonstrated that silt loam soil structure improved with time during transition from intensive tillage to no–till.
On steady states of van der Waals force driven thin film equations

Let , N ≥2 be a bounded smooth domain and α > 1. We are interested in the singular elliptic equation with Neumann boundary conditions. In this paper, a complete description of all continuous radially symmetric solutions is given. In particular, we construct nontrivial smooth solutions as well as rupture solutions. Here a continuous solution is said to be a rupture solution if its zero set is nonempty. When N = 2 and α = 3, the equation is used to model steady states of van der Waals force driven thin films of viscous fluids. We also consider the physical problem when total volume of the fluid is prescribed.
Eta invariants as sliceness obstructions and their relation to Casson-Gordon invariants

We give a useful classification of the metabelian unitary repre- sentations of π1(MK), where MK is the result of zero-surgery along a knot K ⊂ S 3 . We show that certain eta invariants associated to metabelian representations π1(MK) → U(k) vanish for slice knots and that even more eta invariants vanish for ribbon knots and doubly slice knots. We show that our vanishing results contain the Casson-Gordon sliceness obstruction. In many cases eta invariants can be easily computed for satellite knots. We use this to study the relation between the eta invariant sliceness obstruction, the eta-invariant ribbonness obstruction, and the L 2 -eta invariant sliceness obstruction recently introduced by Cochran, Orr and Teichner. In partic- ular we give an example of a knot which has zero eta invariant and zero metabelian L 2 -eta invariant sliceness obstruction but which is not ribbon. AMS Classification 57M25, 57M27; 57Q45, 57Q60
Simulation-based Investigation of a Model for the Interaction between Stellar Magnetospheres and Circumstellar Accretion Disks

We examine, parametrically, the interaction between the magnetosphere of a rotating young stellar object and a circumstellar accretion disk using 2.5-dimensional (cylindrically symmetric) numerical magnetohydrodynamic simulations. The interaction drives a collimated outflow, and we find that the jet formation mechanism is robust. For variations in initial disk density of a factor of 16, variations of stellar dipole strength of a factor of 4, and various initial conditions with respect to the disk truncation radius and the existence of a disk field, outflows with similar morphologies were consistently produced. Second, the system is self-regulating, where the outflow properties depend relatively weakly on the parameters above. The large-scale magnetic field structure rapidly evolves to a configuration that removes angular momentum from the disk at a rate that depends most strongly on the field and weakly on the rotation rate of the footpoints of the field in the disk and the mass outflow rate. Third, the simulated jets are episodic, with the timescale of jet outbursts identical to the timescale of magnetically induced oscillations of the inner edge of the disk. To better understand the physics controlling these disk oscillations, we present a semianalytical model and confirm that the oscillation period is set by the spin-down rate of the disk inner edge. Finally, our simulations offer strong evidence that it is indeed the interaction of the stellar magnetosphere with the disk, rather than some primordial field in the disk itself, that is responsible for the formation of jets from these systems.
A straightforward synthesis of pentosidine framework

The concise synthesis of the pentosidine framework (X) consists of a five-step sequence which provides the target compound in a satisfactory overall yiel (75%).
Hydration of Kr(aq) in dilute and concentrated solutions

Molecular dynamics simulations of water with both multi-Kr and single Kr atomic solutes are carried out to implement quasi-chemical theory evaluation of the hydration free energy of Kr(aq). This approach obtains free energy differences reflecting Kr–Kr interactions at higher concentrations. Those differences are negative changes in hydration free energies with increasing concentrations at constant pressure. The changes are due to a slight reduction of packing contributions in the higher concentration case. The observed Kr–Kr distributions, analyzed with the extrapolation procedure of Kruger et al., yield a modestly attractive osmotic second virial coefficient, B2 ≈ −60 cm3/mol. The thermodynamic analysis interconnecting these two approaches shows that they are closely consistent with each other, providing support for both approaches.
A highly efficient and selective synthesis of lissoclinolide featuring hydrogen transfer hydrozirconation,trans-selective Pd-catalyzed cross coupling of alkenylzirconiums with 1,1-dibromoalkenes and Ag-catalyzed lactonization providing(Z)-γ-alkylidenebutenolides

Abstract An antibiotic lissoclinolide has been synthesized from propargyl alcohol in 9 steps and in 32% overall yield via (i) hydrogen transfer hydrozirconation of TBS-protected propargyl alcohol with i -BuZrCp 2 Cl, (ii) Pd-catalyzed trans -selective cross coupling of the hydrozirconation product with a key 1,1-dibromoalkene intermediate 5 and (iii) Ag-catalyzed lactonization of a trienynoic acid precursor 2 .
Disease and Development: Evidence from Hookworm Eradication in the American South

This study evaluates the economic consequences of the successful eradication of hookworm disease from the American South. The hookworm-eradication campaign (c. 1910) began soon after (i) the discovery that a variety of health problems among Southerners could be attributed to the disease and (ii) the donation by John D. Rockefeller of a substantial sum to the effort. The Rockefeller Sanitary Commission (RSC) surveyed infection rates in the affected areas (eleven southern states) and found that an average of forty percent of school-aged children were infected with hookworm. The RSC then sponsored treatment and education campaigns across the region. Follow-up studies indicate that this campaign substantially reduced hookworm disease almost immediately. The sudden introduction of this treatment combines with the cross-area differences in pre-treatment infection rates to form the basis of the identification strategy. Areas with higher levels of hookworm infection prior to the RSC experienced greater increases in school enrollment, attendance, and literacy after the intervention. This result is robust to controlling for a variety of alternative factors, including differential trends across areas, changing crop prices, shifts in certain educational and health policies, and the effect of malaria eradication. No significant contemporaneous results are found for adults, who should have benefited less from the intervention owing to their substantially lower (prior) infection rates. A long-term follow-up of affected cohorts indicates a substantial gain in income that coincided with exposure to hookworm eradication. I also find evidence that eradication increased the return to schooling.
Comparison of stream merging algorithms for media-on-demand

Stream merging is a technique for efficiently delivering popular media-on-demand using multicast and client buffers. Recently, several algorithms for stream merging have been proposed, and in this paper we perform a comprehensive comparison of these algorithms. We present the differences in philosophy and mechanics among the various algorithms and illustrate the tradeoffs between their system complexity and performance. We measure performance in total, maximum, and time-varying server bandwidth usage under different assumptions for the client request patterns. We also consider the effects on clients when the server has limited bandwidth. The result of this study is a deeper understanding of the system complexity and performance tradeoffs for the various algorithms.
An examination of the substitution chemistry of di-n-hexyldichlorosilane

Abstract Various nucleophiles were reacted with the substrate di- n -hexyldichlorosilane as model reactions for the substitution of two geminal SiCl bonds on polymer backbone repeat units. The reactants examined were chosen on the basis of steric bulk, electronic factors, and resulting stability of the product. Linear and branched alcohol nucleophiles used in conjunction with an amine proton acceptor produced disubstituted products in moderate yields, whereas bulkier reagents substituted only one siliconchlorine bond. Due to their vastly increased nucleophilicity, alkyllithium reagents were found to have increased activity and were found to produce very high yields.
Heat transfer in tissue containing a prevascular tumor

Abstract A mathematical model which examines the steady state temperature distribution in tissue containing a prevascular tumor is presented. The tumor is modeled as a one-dimensional cancer cell culture consisting of a necrotic core surrounded by a region of live proliferating cells. Skin temperature is expressed as a function of tumor location, tumor size, necrotic region size, and ambient temperature. It is determined that the size of the necrotic region is a critical parameter for detecting the presence of the tumor from the skin temperature.
Synthesis of the securinega alkaloids (±)-norsecurinine and (±)-Nirurine from 3-hydroxypyridine.

Abstract Treatment of the dihydropyridine 5 with fluoride anion resulted in in situ formation of the allenyldiene 4 which cyclized to the azabicyclo[2.2.2]octene 9. Subsequent elaboration to the alcohol 24 and rearrangement gave norsecurinine 2. The intermediate diol 16 was converted into prenirurine 34 which upon conversion into an N-oxide rapidly rearranged to give traces of nirurine 1 and norphyllanthine 38.
US Integrated Ocean Observing System (IOOS®): Delivering benefits to science and society

The United States Integrated Ocean Observing System (IOOS®) is a user-driven, coordinated network of people, organizations, and technology that generate and disseminate continuous data about our coastal waters, Great Lakes, and oceans supported by strong research and development activities. IOOS® is our Eyes on our Oceans, Coasts and Great Lakes that enable the United States to track, predict, manage, and adapt to changes in our marine environment and deliver critical information to decision makers to improve safety, enhance our economy and protect our environment. IOOS provides a major shift in the approach to ocean observing by drawing together the vast network of disparate federal and non-federal observing systems to produce a cohesive suite of data, information, and products on a sufficient geographic and temporal scale to support decision-making. Two interdependent components constitute the U.S. IOOS: (1) the global ocean component, and (2) the coastal component. The strength of IOOS is in its partnerships, starting with the federal agencies, the partnerships extend internationally for the global component and to the local level for the coastal component. The coastal component includes the national set of observations for the U.S. Ocean, Coasts and Great Lakes, a network of Regional Associations that are establishing Regional Coastal Ocean Observing Systems (RCOOS) and the Alliance for Coastal Technologies (ACT). The U.S. IOOS is our nation's contribution to the Global Ocean Observing System (GOOS) — the ocean component of the Global Earth Observation System of Systems (GEOSS).
Bomb calorimetric and NMR studies on crystalline hexaglycine

Abstract The enthalpy of combustion of crystalline hexaglycine (C12H20N6O7cr) has been determined by combustion bomb calorimetry. The molar enthalpy of combustion at 298.15 K for the following reaction: C12H20N6O7(cr) + 13.5O2(g) = 12CO2(g) + 10H2O(1) + 3N2(g) is ΔcHmo = −(5930.3 ± 11.3) kJ mol−1; the corresponding enthalpy of formation at 298.15 K is ΔfHmo = −(1650.1 ± 11.7) kJ mol−1. Because of the difficulty in establishing the moisture content of the sample, the enthalpy of combustion is based upon the mass of carbon dioxide formed in each calorimetric experiment rather than upon the mass of sample prior to combustion. A variety of NMR measurements have been made, both 1H NMR and CP-MAS 13C, to characterize hexaglycine and several other oligoglycines, and to determine the water content of the hexaglycine. The energy contribution to the enthalpy of formation of crystalline hexaglycine for the repeating unit, -(CH2-CO-NH)-, is compared to similar values derived from related peptides and amino acids in the solid phase.
Alternate instrumental methods of measuring scorch and cure characteristics

After the development of the oscillating disk curemeter over 30 years ago, standard conditions for measuring scorch times (time till the onset of vulcanization) were developed. ISO 3417 and ASTM D2084 describe t(s)1 and t(s)2 test parameters which are accepted by the rubber industry as a method for measuring scorch times. t(s)1 is the time until one torque unit rise above minimum torque and t(s)2 is the time until two torque units rise above minimum torque. These parameters are arbitrary and do not measure the 'true' scorch time. Also t(s)1 and t(s)2 may not be an accurate comparison for compounds which differ greatly in their state of cure. Experience has shown that some rotorless curemeter designs are far more sensitive to physicochemical changes occurring during the cure process than the conventional oscillating curemeters. The MDR 2000(R) rotorless curemeter (MDR) and the RPA 2000(TM) Rubber Process Analyzer (RPA) measure subtle changes in viscoelastic properties during the caring process. This paper discusses the feasibility of using the time until the viscous torque (S'') peaks (f??) to more accurately measure the 'true' scorch time. Other techniques for measuring care characteristics are also reviewed for comparison.
The Unfolded Protein Response in a Pair of Sensory Neurons Promotes Entry of C. elegans into Dauer Diapause

Summary In response to unfavorable environmental conditions such as starvation, crowding, and elevated temperature, Caenorhabditis elegan s larvae enter an alternative developmental stage known as dauer [1], which is characterized by adaptive changes in stress resistance and metabolism [2, 3]. The genetic dissection of the molecular mechanisms of the C. elegans dauer developmental decision has defined evolutionarily conserved signaling pathways of organismal neuroendocrine physiology [2–4]. Here, we have identified a mechanism by which a dominant mutation in a neuronal insulin gene, daf-28(sa191) [5–7], causes constitutive entry into dauer diapause. We demonstrate that expression of the mutant DAF-28 insulin peptide results in endoplasmic reticulum (ER) stress in the ASI pair of chemosensory neurons. The neuronal ER stress does not compromise cellular survival but activates PEK-1, the C. elegans ortholog of the mammalian eIF2α kinase PERK, which in turn phosphorylates Ser49 of eIF2α, specifically in the ASI neuron pair, to promote entry into dauer diapause. Our data establish a novel role for ER stress and the unfolded protein response (UPR) in promoting entry into dauer diapause and suggest that, in addition to cell-autonomous activities in the maintenance of ER homeostasis, the UPR may act in a non-cell-autonomous manner to promote organismal adaptation to stress during larval development.
SYNTHESIS OF 3-QUINUCLIDINYL BENZILATE DERIVATIVES

(1990). SYNTHESIS OF 3-QUINUCLIDINYL BENZILATE DERIVATIVES. Organic Preparations and Procedures International: Vol. 22, No. 1, pp. 87-94.
An integral identity with applications in orthogonal polynomials

For $\boldsymbol{\large {\lambda}} = (\lambda_1,\ldots,\lambda_d)$ with $\lambda_i > 0$, it is proved that \begin{equation*} \prod_{i=1}^d \frac{ 1}{(1- r x_i)^{\lambda_i}} = \frac{\Gamma(|\boldsymbol{\large {\lambda}}|)}{\prod_{i=1}^{d} \Gamma(\lambda_i)} \int_{\mathcal{T}^d} \frac{1}{ (1- r \langle x, u \rangle)^{|\boldsymbol{\large {\lambda}}|}} \prod_{i=1}^d u_i^{\lambda_i-1} du, \end{equation*} where $\mathcal{T}^d$ is the simplex in homogeneous coordinates of $\mathbb{R}^d$, from which a new integral relation for Gegenbuer polynomials of different indexes is deduced. The latter result is used to derive closed formulas for reproducing kernels of orthogonal polynomials on the unit cube and on the unit ball.
Transportable English-language processing for office environments

This article describes the Layered Domain Class system (LDC), a state-of-the-art natural language processor whose major goals are (1) to provide English-language retrieval capabilities for medium-sized office domains that have been stored on the computer as text-edited files, rather than more restrictive database structures and (2) to eliminate the need to call in the system designer when extensions into new domains are desired, without sacrificing the depth or reliability of the interface. Early developments in the design of portions of LDC were presented at NCC-83, and the entire system became operational in July 1983. The article gives an overview of the construction of the system, gives examples of the English structures provided for, briefly describes the most recently completed portions of the system, and mentions current directions the project is taking.
Inhomogeneous charge state in HTSC cuprates and CMR manganites

Recent measurements of neutron elastic and inelastic scattering suggest that the charge states are spatially inhomogeneous at two length scales, atomic and nanometer scales, in both the high-temperature superconducting (HTSC) cuprates and colossal magnetoresistive (CMR) manganites. We suggest that the two-phonon mechanism that controls the charge localization in CMR manganites is also at work in HTSC cuprates, and may hold a key to understanding the mechanism of superconductivity.
Towards low-threshold, real-time solar neutrino detectors

We discuss an alternative approach to the detection of solar neutrinos using a coarsely segmented detector based on inverse-beta decay onto 160Gd or 176Yb. While it is known that similar approaches, already discussed in the literature, can in principle provide low-threshold, real-time energy spectroscopy with intrinsic background rejection features, the concepts presented here make this scheme possible with lower background and current technology.
Volumetric depth peeling for medical image display

Volumetric depth peeling (VDP) is an extension to volume rendering that enables display of otherwise occluded features in volume data sets. VDP decouples occlusion calculation from the volume rendering transfer function, enabling independent optimization of settings for rendering and occlusion. The algorithm is flexible enough to handle multiple regions occluding the object of interest, as well as object self-occlusion, and requires no pre-segmentation of the data set. VDP was developed as an improvement for virtual arthroscopy for the diagnosis of shoulder-joint trauma, and has been generalized for use in other simple and complex joints, and to enable non-invasive urology studies. In virtual arthroscopy, the surfaces in the joints often occlude each other, allowing limited viewpoints from which to evaluate these surfaces. In urology studies, the physician would like to position the virtual camera outside the kidney collecting system and see inside it. By rendering invisible all voxels between the observer's point of view and objects of interest, VDP enables viewing from unconstrained positions. In essence, VDP can be viewed as a technique for automatically defining an optimal data- and task-dependent clipping surface. Radiologists using VDP display have been able to perform evaluations of pathologies more easily and more rapidly than with clinical arthroscopy, standard volume rendering, or standard MRI/CT slice viewing.
Environmental transformations of silver nanoparticles: impact on stability and toxicity.

Silver nanoparticles (Ag-NPs) readily transform in the environment, which modifies their properties and alters their transport, fate, and toxicity. It is essential to consider such transformations when assessing the potential environmental impact of Ag-NPs. This review discusses the major transformation processes of Ag-NPs in various aqueous environments, particularly transformations of the metallic Ag cores caused by reactions with (in)organic ligands, and the effects of such transformations on physical and chemical stability and toxicity. Thermodynamic arguments are used to predict what forms of oxidized silver will predominate in various environmental scenarios. Silver binds strongly to sulfur (both organic and inorganic) in natural systems (fresh and sea waters) as well as in wastewater treatment plants, where most Ag-NPs are expected to be concentrated and then released. Sulfidation of Ag-NPs results in a significant decrease in their toxicity due to the lower solubility of silver sulfide, potentiall...
Seasonal variations of Antarctic clouds observed by CloudSat and CALIPSO satellites

[1] The multiyear lidar and radar measurements obtained from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) and CloudSat between June 2006 and May 2010 were used to investigate the seasonal and interannual variabilities of the vertical and horizontal cloud distributions, cloud top height above ground (Htop) thickness (CTH), effective radius (re), and ice water content (IWC) over the southern high latitudes poleward of 60°S. The collocated lidar and radar data were used to derive the cloud mask, which was used to classify the clouds into four classes according to the cloud base height above ground (Hbase) and CTH. The Amundsen/Bellingshausen Sea region showed the highest cloud occurrence (>80%) and Antarctic Plateau had lowest cloud occurrence (<30%). The low-level clouds accounted for more than 60% of the total cloudiness, and their occurrence was greater during summer than during winter, but deep and high-level cloud occurrence, CTH, and Htop were greater during winter than during summer. CTH and Htopof deep and high-level clouds were greater over ocean than over land, but both CTH and Htopof low-level clouds were greater over land than over ocean. The mean IWCs for high-level clouds over land and ocean were 0.85 (2.0) and 1.3 (3.1) mg/kg, respectively, and the mean re over land and ocean were 18.0 (22.1) and 21.5 (26.4) μm, respectively, for winter (summer). The study provides a high-quality data set of cloud properties over the Antarctic region to improve our understanding and model simulations of Antarctic clouds.
Dynamic weighting Monte Carlo for constrained floorplan designs in mixed signal application

Simulated annealing has been one of the most popular stochastic optimization methods used in the VLSI CAD field in the past two decades. Recently, a new Monte Carlo and optimization method, named dynamic weighting Monte Carlo [WL97], has been introduced and successfully applied to the traveling salesman problem, neural network training [WL97], and spin-glasses simulation [LW99]. In this paper, we have successfully applied dynamic weighting Monte Carlo algorithm to the constrained floorplan design with consideration of both area and wirelength minimization. Our application scenario is the constrained floorplan design for mixed signal MCMs, where we need to place all the analog modules together in groups so that they can share common power and ground and are separate from those used by the digital modules. Our experiments indicate that the dynamic weighting Monte Carlo algorithm is very effective for constrained floorplan optimization. It outperforms the simulated annealing for a real mixed signal MCM design by 19.5% in wirelength, with slight area improvement. This is the first work adopting the dynamic weighting Monte Carlo optimization method for solving VLSI CAD problems. We believe that this method has applications to many other VLSI CAD optimization problems.