cssi/SciSciGPT-SciSciNet huggingface dataset:
Effects of the Built Environment on Childhood Obesity: the Case of Urban Recreational Trails and Crime

We study the effects of urban environment on childhood obesity by concentrating on the effects of walking trails and crime close to children’s homes on their BMI and obesity status. We use a unique dataset, which combines information on recreational trails in Indianapolis with data on violent crimes and anthropomorphic and diagnostic data from children’s clinic visits between 1996 and 2005. We find that having a trail near a home reduces children’s weight. However, the effect depends on the amount of nearby violent crimes. Significant reductions occur only in low crime areas and trails could have opposite effects on weight in high crime areas. These effects are primarily among boys, older children, and children who live in higher income neighborhoods. Evaluated at the mean length of trails this effect for older children in no crime areas would be a reduction of two pounds of the body weight. Falsification tests using planned trails instead of existing trails, show that trails are more likely to be located in areas with heavier children, suggesting that our results on effects of trails represent a lower bound.
Web document clustering using hyperlink structures

With the exponential growth of information on the World Wide Web, there is great demand for developing efficient methods for effectively organizing the large amount of retrieved information. Document clustering plays an important role in information retrieval and taxonomy management for the Web. In this paper we examine three clustering methods: K-means, multi-level METIS, and the recently developed normalized-cut method using a new approach of combining textual information, hyperlink structure and co-citation relations into a single similarity metric. We found the normalized-cut method with the new similarity metric is particularly effective, as demonstrated on three datasets of web query results. We also explore some theoretical connections between the normalized-cut method and the K-means method.
Synthesis of highly functionalized cyclohexenone rings: rhodium-catalyzed 1,3-acyloxy migration and subsequent [5+1] cycloaddition.

The Diels–Alder cycloaddition represents the most powerful technology for the preparation of substituted cyclohexenes and has proven to be extremely valuable in organic synthesis.[1] However, efficient syntheses of cyclohexenes having diverse substitutions, stereochemistry, and functionalities are still challenging and continue to stimulate the development of novel cycloaddition reactions.[2] We report herein a stereoselective synthesis of highly functionalized cyclohexenones from substituted cyclopropanes through a rhodium-catalyzed 1,3-acyloxy migration and subsequent [5+1] cycloaddition. Given the well-documented strategies for the preparation of optically pure cyclopropanes,[3] this promises to be a versatile method for the synthesis of complex cyclohexenones from cyclopropanes.[4]
Zinc metalloproteins as medicinal targets

Zinc bioinorganic chemistry has emphasized the role of the metal ion on the structure and function of the protein. There is, more recently, an increasing appreciation of the role of zinc proteins in a variety of human diseases. This critical review, aimed at both bioinorganic and medicinal chemists, shows how apparently widely-diverging diseases share the common mechanistic approaches of targeting the essential function of the metal ion to inhibit activity. Protein structure and function is briefly summarized in the context of its clinical relevance. The status of current and potential inhibitors is discussed along with the prospects for future developments (162 references).
Active sites and states in the heterogeneous catalysis of carbon-hydrogen bonds.

C–H bond activation for several alkenes (ethylene, propylene, isobutene, cyclohexene and 1-hexene) and alkanes (methane, ethane, n-hexane, 2-methylpentane and 3-methylpentane) has been studied on the (111) crystal face of platinum as a function of temperature at low (!10 K6 Torr) and high (R1 Torr) pressures in the absence and presence of hydrogen pressures (R10 Torr). Sum frequency generation (SFG) vibrational spectroscopy has been used to characterize the adsorbate structures and high pressure scanning tunnelling microscopy (HP-STM) has been used to monitor their surface mobility under reaction conditions during hydrogenation, dehydrogenation and CO poisoning. C–H bond dissociation occurs at low temperatures, approximately 250 K, for all of these molecules, although only at high pressures for the weakly bound alkanes because of their low desorption temperatures. Bond dissociation is known to be surface structure sensitive and we find that it is also accompanied by the restructuring of the metal surface. The presence of hydrogen slows down dehydrogenation and for some of the molecules it influences the molecular rearrangement, thus altering reaction selectivity. Surface mobility of adsorbates is essential to produce catalytic activity. When surface diffusion is inhibited by CO adsorption, ordered surface structures form and the reaction is poisoned. Ethylene hydrogenation is surface structure insensitive, while cyclohexene hydrogenation and dehydrogenation are structure sensitive. n-Hexane and other C6 alkanes form either upright or flat-lying molecules on the platinum surface which react to produce branched isomers or benzene, respectively.
An organization for optical linkages between integrated circuits

Conventional integrated circuit packaging techniques which use pins for input-output have several disadvantages, which are becoming increasingly important as more logic is put on a chip. Recent intensive development of optical links for long distance communications suggests that they could be used between integrated circuits, to alleviate the bottleneck created by the connection technology, so that LSI technology can be further exploited. However, the complex linkages between integrated circuit cannot be economically realized by just replacing each wire by an optical link; rather a "bus organization" should be developed so that, by time multiplexing one optical link that threads just once through each integrated circuit, different time slots can be used to realize any necessary transfer. Additionally, the time slices are controlled by a microprogram, so that "wiring changes" can be realized by program changes. A unified treatment of busses is first developed, then two physical realizations of the time-multiplexed bus are described.
IRREGULAR SATELLITES IN THE CONTEXT OF PLANET FORMATION

All four giant planets in the solar system possess irregular satellites, characterized by large, highly eccentric and/or highly inclined orbits. These bodies were likely captured from heliocentric orbit, probably in association with planet formation itself. Enabled by the use of large-format digital imagers on ground-based telescopes, new observational work has dramatically increased the known populations of irregular satellites, with 74 discoveries in the last few years. A new perspective on the irregular satellite systems is beginning to emerge. We find that the number of irregular satellites measured to a given diameter is approximately constant from planet to planet. This is surprising, given the radically different formation scenarios envisioned for the gas giants Jupiter and Saturn compared to the (much less massive and compositionally distinct) ice giants Uranus and Neptune. We discuss the new results on the irregular satellites and show how these objects might be used to discriminate amongst models of giant planet formation.
WHY CONDUCTIVITY DECREASES WITH PRESSURE IN ION-DOPED POLYMERS

The relaxation time scale in glassy materials is derived within a model of anomalous defect diffusion. The effect of the defects on ion-doped polymeric glasses is to produce a stretched exponential waiting time distribution for ion jumps. The characteristic time scale for ion jumps is connected to the temperature and pressure dependent concentration of mobile defects. The resultant expression for ionic conductivity is compared with experimental results for the polymer electrolyte poly(propylene glycol) (PPG) containing LiCF3SO3.
Multimedia and Online Video Case Studies for Preservice Teacher Preparation

Case studies have been used successfully as a part of teacher education. There are many possibilities in extending the impact of case studies through the use of technology. Video and the Internet could enable demonstration of more examples, dissemination beyond the walls of the classroom, and discussion between geographically dispersed preservice teachers. Several projects are now investigating the possible ways that technology might enhance or extend text case studies. After exploring four existing products, four essential elements for video case studies are proposed. As video case studies move to the Internet, additional issues arise and these are also explored.
Vertical scales and dynamics of eddies in the Arctic Ocean's Canada Basin

A decade of moored measurements from the Arctic Ocean’s northwestern Beaufort Gyre (collected as a component of the Beaufort Gyre Exploration Project) are analyzed to examine the range of mesoscale eddies over the water column and the dynamical processes that set eddy vertical scales. A total of 58 eddies were identified in the moored record, all anticyclones with azimuthal velocities ranging from 10 to 43 cm/s. These are divided into three classes based on core depths. Shallow eddies (core depths around 120 m) are shown to be vertically confined by the strong stratification of the halocline; typical thicknesses are around 100 m. Deep eddies (core depths around 1200 m) are much taller (thicknesses around 1300 m) owing to the weaker stratification at depth, consistent with a previous study. Eddies centered around mid-depths all have two cores (vertically aligned and separated in depth) characterized by velocity maxima and anomalous temperature and salinity properties. One core is located at the base of the halocline (around 200 m depth) and the other at the depth of the Atlantic Water layer (around 400 m depth). These double-core eddies have vertical scales between those of the shallow and deep eddies. The strongly decreasing stratification in their depth range motivates a derivation for the quasi-geostrophic adjustment of a nonuniformly stratified water column to a potential vorticity anomaly. The result aids in interpreting the dynamics and origins of the double-core eddies, providing insight into transport across a major water mass front separating Canadian and Eurasian Water.
Foobaz: Variable Name Feedback for Student Code at Scale

Current traditional feedback methods, such as hand-grading student code for substance and style, are labor intensive and do not scale. We created a user interface that addresses feedback at scale for a particular and important aspect of code quality: variable names. We built this user interface on top of an existing back-end that distinguishes variables by their behavior in the program. Therefore our interface not only allows teachers to comment on poor variable names, they can comment on names that mislead the reader about the variable's role in the program. We ran two user studies in which 10 teachers and 6 students created and received feedback, respectively. The interface helped teachers give personalized variable name feedback on thousands of student solutions from an edX introductory programming MOOC. In the second study, students composed solutions to the same programming assignments and immediately received personalized quizzes composed by teachers in the previous user study.
A NUMERICAL EXPERIMENT ON THE DEVELOPMENT OF A TROPICAL CYCLONE

Abstract A model of a tropical cyclone is constructed which is based upon conservation of momentum, mass,water vapor and heat in the hydrostatic system. The horizontal and vertical eddy-exchange processes for momentum, moisture and heat are included in the equations in order to incorporate the planetary frictional (Ekman) layer into the model. The effects of the surface boundary (Prandtl) layer are simulated by the boundary conditions for the equations, which permit the evaluation of surface stress, the sensible heat transport and the evaporation of water vapor from the earth surface. The energy sources of the model are the latent heat of condensation released during the ascent of moist air and the sensible heat transported from the ocean surface. The formulation of the finite-difference equations for the axially-symmetric case is presented, together with an examination of the computational stability. By means of a high-speed computer, two independent computations with and without the supply of latent hea...
Preventing arithmetic overflows in Alloy

In a bounded analysis, arithmetic operators become partial, and a different semantics becomes necessary. One approach, mimicking programming languages, is for overflow to result in wrap-around. Although easy to implement, wrap-around produces unexpected counterexamples that do not correspond to cases that would arise in the unbounded setting. This paper describes a new approach, implemented in the latest version of the Alloy Analyzer, in which instances that would involve overflow are suppressed, and consequently, spurious counterexamples are eliminated. The key idea is to interpret quantifiers so that bound variables range only over values that do not cause overflow. A new treatment of partial functions in classical logic.Goal: suppress variable bindings causing out-of-domain applications.Idea: assign truth values to undefined formulas to make them globally irrelevant.Applied to Alloy (a bounded model finder) to prevent arithmetic overflows.Result: the Alloy Analyzer made sound with respect to counterexamples.
Large-Scale Conflicts in Massively Multiplayer Online Games

Complex systems are of interest to the scientific community due to their ubiquity and diversity in daily life. Popularity notwithstanding, the analysis of complex systems remains a difficult task, due to the problems in capturing high-volume data. Massively Multiplayer Online Games (MMOGs) have recently emerged as a tractable way to analyze complex system interactions, because these virtual environments are able to capture a great amount of data and at high-fidelity, often tracking the actions of many individuals at a time resolution of seconds. MMOGs have been used to study phenomena such as social networks and financial systems; our focus is to identify behaviors related to Large-Scale Conflict (LSC). In this paper, we review how one particular MMOG allows large-scale complex behavior to emerge and we draw parallels between virtual-world LSCs and real-world LSCs. The LSC-related behavior that we are interested in identifying deals with the conditions that lead a participant in the virtual environment (a game player) to engage and actively participate in a LSC, with the goal of informing an agent-based model that predicts when any one player is likely to engage in conflict. We identify virtual world behavioral analogues to real-world behavior of interest (i.e. insurgent behavior), and link the virtual behavior to a (previously derived) theoretical framework that analyzes the determinants of participation in the civil war of Sierra Leone. This framework identifies three general theories that collectively predict participation in civil war (a type of LSC); we operationalize one of the theories (Theory of Social Sanctions), and look at how insurgent behavior can occur as a function of community networks, which are assumed to impose social sanctions for non-participation in an LSC.
A single-flask synthesis of α-alkylidene and α-benzylidene lactones from ethoxyacetylene, epoxides/oxetanes, and carbonyl compounds

Low temperature treatment of (ethoxyethynyl)lithium with epoxides or oxetanes in the presence of BF3•OEt2, followed by addition of aldehydes or ketones and warming to room temperature, affords structurally diverse five- and six-membered α-alkylidene and α-benzylidene lactones (5) in good to excellent yields. This one-pot process, in which three new carbon-carbon bonds and a ring are formed, affords substituted α,β-unsaturated lactones of predominantly Z-configuration. The reaction likely occurs via alkyne-carbonyl metathesis of a hydroxy-ynol ether intermediate, acid-promoted alkene E- to Z-isomerization, and lactonization.
ASP flood of a viscous oil in a carbonate rock

Abstract The goal of this work is to develop an alkaline–surfactant–polymer (ASP) formulation for a viscous oil (105 cP at the reservoir temperature) and compare secondary and tertiary ASP floods. Phase behavior studies were performed to find an ultralow interfacial tension (IFT) ASP formulation for the viscous oil. Static surfactant adsorption experiments were performed to compare the effectiveness of different alkalis in reducing adsorption. The surfactant formulation was tested with an outcrop vuggy dolomite core in both tertiary and secondary modes. Lab coreflood results were modeled in UTCHEM which used EQBATCH to model sodium metaborate geochemical reactions in a carbonate rock. Sodium carbonate and sodium metaborate were both found to be equally effective in reducing surfactant adsorption on crushed dolomite. Waterflood recovered about 47.8% of the oil in place and reduced the oil saturation to 43.8%. The tertiary surfactant flood increased the cumulative oil recovery to 92.7% whereby the oil saturation was reduced to 6.1%. The secondary surfactant flood was even more effective than the tertiary; the oil saturation was reduced to 3.1% and the oil recovery was 95.6% OOIP. Very low surfactant retention was observed in the ASP corefloods. UTCHEM simulations showed a reasonable match with the experimental results. Experimental data for surfactant phase behavior, polymer viscosity, and surfactant adsorption were critical in modeling the experimental results.
Nucleophilic Activation of Carbon Monoxide: Applications to Homogeneous Catalysis by Metal Carbonyls of the Water Gas Shift and Related Reactions

Publisher Summary This chapter discusses the roles played by certain nucleophile adducts of metal–coordinated carbon monoxide in the stoichiometric and catalytic chemistry of metal–carbonyl complexes and relatively recent developments for systems where oxygen or nitrogen bases have been used as the nucleophiles. The syntheses, spectral characterizations, and chemical reaction studies of various nucleophile–carbonyl complexes are described with the goal of drawing attention to how such adduct formation not only activates the carbonyl directly involved for further reaction but also influences the reactivities of the balance of the complex. Preparation by direct addition of a nucleophile anion Nu – to a coordinated CO has been a widely applicable approach. Nuclear magnetic resonance (especially 13 C NMR) and infrared spectroscopy have proved the most used and successful diagnostic tools in characterizing the formation and transformations of various L n M–(CO)Nu complexes and related species. Reactions of uncharged nucleophiles with coordinated CO provide a different situation. Kinetics studies of systems for which characterizable nucleophilecarbonyl adducts have been isolated are relatively few.
Advanced Fabrication Processes for Superconducting Very Large-Scale Integrated Circuits

We review the salient features of two advanced nodes of an 8-Nb-layer fully planarized process developed recently at MIT Lincoln Laboratory for fabricating single flux quantum (SFQ) digital circuits with very large-scale integration on 200-mm wafers: the SFQ4ee and SFQ5ee nodes, where “ee” denotes that the process is tuned for energy-efficient SFQ circuits. The former has eight superconducting layers with 0.5- $\mu\text{m}$ minimum feature size and a 2- $\Omega/\text{sq}$ Mo layer for circuit resistors. The latter has nine superconducting layers: eight Nb wiring layers with the minimum feature size of 350 nm and a thin superconducting $\text{MoN}_{{x}}$ layer $(T_c \sim 7.5\ \text{K})$ with high kinetic inductance (about 8 pH/sq) for forming compact inductors. A nonsuperconducting $(T_{c} layer with lower nitrogen content is used for 6- $\Omega/\text{sq}$ planar resistors for shunting and biasing of Josephson junctions (JJs). Another resistive layer is added to form interlayer sandwich-type resistors of milliohm range for releasing unwanted flux quanta from superconducting loops of logic cells. Both process nodes use Au/Pt/Ti contact metallization for chip packaging. The technology utilizes one layer of Nb/AlOx-Al/Nb JJs with critical current density $J_{c}$ of 100 $\mu\text{A}/\mu\text{m}^{2}$ and minimum diameter of 700 nm. Circuit patterns are defined by 248-nm photolithography and high-density plasma etching. All circuit layers are fully planarized using chemical mechanical planarization of SiO2 interlayer dielectric. The following results and topics are presented and discussed: the effect of surface topography under the JJs on the their properties and repeatability, $I_c$ and $J_c$ targeting, effect of hydrogen dissolved in Nb, $\text{MoN}_{x}$ properties for the resistor layer and for high-kinetic-inductance layer, and technology of milliohm-range resistors.
Novel ZE-isomerism descriptors derived from molecular topology and their application to QSAR analysis.

We introduce several series of novel ZE-isomerism descriptors derived directly from two-dimensional molecular topology. These descriptors make use of a quantity named ZE-isomerism correction, which is added to the vertex degrees of atoms connected by double bonds in Z and E configurations. This approach is similar to the one described previously for topological chirality descriptors (Golbraikh, A., et al. J. Chem. Inf. Comput. Sci. 2001, 41, 147−158). The ZE-isomerism descriptors include modified molecular connectivity indices, overall Zagreb indices, extended connectivity, overall connectivity, and topological charge indices. They can be either real or complex numbers. Mathematical properties of different subgroups of ZE-isomerism descriptors are discussed. These descriptors circumvent the inability of conventional topological indices to distinguish between Z and E isomers. The applicability of ZE-isomerism descriptors to QSAR analysis is demonstrated in the studies of a series of 131 anticancer agents i...
Scalable models for computing hierarchies in information networks

Information hierarchies are organizational structures that often used to organize and present large and complex information as well as provide a mechanism for effective human navigation. Fortunately, many statistical and computational models exist that automatically generate hierarchies; however, the existing approaches do not consider linkages in information networks that are increasingly common in real-world scenarios. Current approaches also tend to present topics as an abstract probably distribution over words, etc., rather than as tangible nodes from the original network. Furthermore, the statistical techniques present in many previous works are not yet capable of processing data at Web-scale. In this paper, we present the hierarchical document-topic model (HDTM), which uses a distributed vertex-programming process to calculate a nonparametric Bayesian generative model. Experiments on three medium- size data sets and the entire Wikipedia data set show that HDTM can infer accurate hierarchies even over large information networks.
Perioperative thermoregulation and heat balance.

Summary Core body temperature is normally tightly regulated to within a few tenths of a degree. The major thermoregulatory defences in humans are sweating, arteriovenous shunt vasoconstriction, and shivering. The core temperature triggering each response defines its activation threshold. General anaesthetics greatly impair thermoregulation, synchronously reducing the thresholds for vasoconstriction and shivering. Neuraxial anaesthesia also impairs central thermoregulatory control, and prevents vasoconstriction and shivering in blocked areas. Consequently, unwarmed anaesthetised patients become hypothermic, typically by 1–2°C. Hypothermia results initially from an internal redistribution of body heat from the core to the periphery, followed by heat loss exceeding metabolic heat production. Complications of perioperative hypothermia include coagulopathy and increased transfusion requirement, surgical site infection, delayed drug metabolism, prolonged recovery, shivering, and thermal discomfort. Body temperature can be reliably measured in the oesophagus, nasopharynx, mouth, and bladder. The standard-of-care is to monitor core temperature and to maintain normothermia during general and neuraxial anaesthesia.
Controlled excitation of a cold turbulent swirling free jet

Experimental results from acoustic excitation of a cold free turbulent jet with and without swirl are presented. A flow with a swirl number of 0.35 (i.e., moderate swirl) is excited internally by plane acoustic waves at a constant sound pressure level and at various frequencies. It is observed that the cold swirling jet is excitable by plane waves, and that the instability waves grow about 50 percent less in peak rms amplitude, and saturate further upstream compared to corresponding waves in a jet without swirl having the same axial mass flux. The preferred Strouhal number based on the mass-averaged axial velocity and nozzle exit diameter for both swirling and nonswirling flows is 0.4. So far no change in the mean velocity components of the swirling jet is observed as a result of excitation.
On the Finite Sample Properties of Regularized M-Estimators

We propose a general framework for regularization in M-estimation problems under time dependent (absolutely regular-mixing) data which encompasses many of the existing estimators. We derive non-asymptotic concentration bounds for the regularized M-estimator. The concentration rate exhibits a “variance-bias” trade-off, with the “variance” term being governed by a novel measure of the “size” of the parameter set. We also show that the mixing structure affect the variance term by scaling the number of observations; depending on the decay rate of the mixing coefficients, this scaling can even affect the asymptotic behavior. Finally, we propose a data-driven method for choosing the tuning parameters of the regularized estimator which yield the same (up to constants) concentration bound as one that optimally balances the “(squared) bias” and “variance” terms. We illustrate the results with several canonical examples of, both, non-parametric and high-dimensional models.
THE REPRESENTATION OF CONSTITUENT STRUCTURES FOR FINITE-STATE PARSING

A mixed prefix-postfix notation for representations of the constituent structures of the expressions of natural languages is proposed, which are of limited degree of center embedding if the original expressions are noncenter-embedding. The method of constructing these representations is applicable to expressions with center embedding, and results in representations which seem to reflect the ways in which people actually parse those expressions. Both the representations and their interpretations can be computed from the expressions from left to right by finite-state devices.The class of acceptable expressions of a natural language L all manifest no more than a small, fixed, finite degree n of center embedding. From this observation, it follows that the ability of human beings to parse the expressions of L can be modeled by a finite transducer that associates with the acceptable expressions of L representations of the structural descriptions of those expressions. This paper considers some initial steps in the construction of such a model. The first step is to determine a method of representating the class of constituent structures of the expressions of L without center embedding in such a way that the members of that class themselves have no more than a small fixed finite degree of center embedding. Given a grammar that directly generates that class of constituent structures, it is not difficult to construct a deterministic finite-state transducer (parser) that assigns the appropriate members of that class to the noncenter-embedded expressions of L from left to right. The second step is to extend the method so that it is capable of representing the class of constituent structures of expressions of L with no more than degree n of center embedding in a manner which appears to accord with the way in which human beings actually parse those sentences. Given certain reasonable assumptions about the character of the rules of grammar of natural languages, we show how this step can also be taken.
Thermoelectric properties of semiconductor nanowire networks

To examine the thermoelectric (TE) properties of a semiconductor nanowire (NW) network, we propose a theoretical approach mapping the TE network on a two-port network. In contrast to a conventional single-port (i.e., resistor) network model, our model allows for large scale calculations showing convergence of TE figure of merit, ZT, with an increasing number of junctions. Using this model, numerical simulations are performed for the Bi2Te3 branched nanowire (BNW) and Cayley tree NW (CTNW) network. We find that the phonon scattering at the network junctions plays a dominant role in enhancing the network ZT. Specifically, disordered BNW and CTNW demonstrate an order of magnitude higher ZT enhancement compared to their ordered counterparts. Formation of preferential TE pathways in CTNW makes the network effectively behave as its BNW counterpart. We provide formalism for simulating large scale nanowire networks hinged upon experimentally measurable TE parameters of a single T-junction.
Triangulable Leibniz Algebras

A converse to Lie's theorem for Leibniz algebras is found and generalized. The result is used to find cases in which the generalized property, called triangulable, is 2-recognizable; that is, if all 2-generated subalgebras are triangulable, then the algebra is also. Triangulability joins solvability, supersolvability, strong solvability, and nilpotentcy as a 2-recognizable property for classes of Leibniz algebras.
Deficit Irrigation and Vine Mineral Nutrition

Water and nutrients exist together in close association because plant-available nutrient ions are dissolved in the soil solution and nutrient uptake by grapevines depends on water flow through the soil-root-shoot pathway. Leaf transpiration generates the tension necessary for the roots to absorb this essential solution, but in a drying soil, uptake of water and nutrients becomes progressively more difficult for grapevines. In addition, application of nitrogen fertilizer can increase the vine’s susceptibility to drought, because nitrogen favors shoot growth over root growth. However, because growth is more sensitive than photosynthesis to both water and nitrogen shortage, deficit irrigation may be used in conjunction with limited nitrogen application to control canopy development, yield, and fruit composition. Growth is the “pacemaker” for nutrient uptake by the vine, hence the growth reduction induced by water deficit also decreases vine nutrient requirements. Nevertheless, reducing water or nitrogen supply can be perceived as a stress by the vine, and its response depends on developmental status. For instance, water deficit applied before fruit set may reduce cluster and berry numbers, especially if combined with nitrogen shortage. Properly regulated deficit irrigation in combination with low to moderate rates of nitrogen application between bloom and veraison reduces canopy size, berry size, and yield, accelerates ripening, improves fruit color, and reduces disease incidence. However, this strategy also reduces yeast-assimilable nitrogen in the fruit, thereby increasing the risk of sluggish or stuck fermentation. Moreover, if the water or nitrogen deficit becomes too severe, fruit quality suffers from both limited assimilate supply and excessive fruit exposure to sunlight. The relationship between vine nutrition and deficit irrigation clearly requires careful guidance to make it a happy one.
Environmental Justice Delayed: Failed Promises, Hope for the Future

Environmental justice has reemerged on the U.S. federal policy agenda. After more than two decades of fits and starts, the U.S. Environmental Protection Agency (EPA) during the Obama Administration...
Efficient simulation for branching linear recursions

We provide an algorithm for simulating the unique attracting fixed-point of linear branching distributional equations. Such equations appear in the analysis of information ranking algorithms, e.g., PageRank, and in the complexity analysis of divide and conquer algorithms, e.g., Quicksort. The naive simulation approach would be to simulate exactly a suitable number of generations of a weighted branching process, which has exponential complexity in the number of generations being sampled. Instead, we propose an iterative bootstrap algorithm that has linear complexity; we prove its convergence and the consistency of a family of estimators based on our approach.
Seizure Prediction and Detection via Phase and Amplitude Lock Values.

A robust seizure prediction methodology would enable a ‘closed-loop’ system that would only activate as impending seizure activity is detected. Such a system would eliminate ongoing stimulation to the brain, thereby eliminating such side effects as coughing, hoarseness, voice alteration, and paresthesias (Murphy et al., 1998, Ben-Menachem, 2001), while preserving overall battery life of the system. The seizure prediction and detection algorithm uses Phase/Amplitude Lock Values (PLV/ALV) which calculate the difference of phase and amplitude between EEG electrodes local and remote to the epileptic event. PLV is used as the seizure prediction marker and signifies the emergence of abnormal neuronal activations through local neuron populations. PLV/ALVs are used as seizure detection markers to demarcate the seizure event, or when the local seizure event has propagated throughout the brain turning into a grand-mal event. We verify the performance of this methodology against the ‘CHB-MIT Scalp EEG Database’ which features seizure attributes for testing. Through this testing, we can demonstrate a high degree of sensivity and precision of our methodology between pre-ictal and ictal events.
Multiple Sclerosis: MRI and Clinical Correlation

Fifty-three consecutive patients with suspected multiple sclerosis were studied to determine if the extent of disease apparent on MRI correlated with the clinical severity of the disease. MRI images were evaluated and compared with an assessment of the patient9s disability using three neurologic rating scales. The severity of the disease seen on MRI showed a strong statistically significant correlation ( p = 0.0001) with two of the three methods of clinical evaluation and a significant correlation ( p p = 0.05) with the length of time the patients had been symptomatic. Normal controls did not show any abnormality characteristic of multiple sclerosis on MRI or on neurologic exam.
Use of Perinatal and Infant Health Services by Mexican-American Medicaid Enrollees

Objectives. —Lack of health insurance and a regular source of medical care are barriers affecting use of health services by Mexican Americans. We studied perinatal and infant health service use by Mexican-American women and non-Hispanic white women and their infants enrolled in Arizona's Medicaid program and explored characteristics associated with use of health services. Design. —A descriptive comparative study that used data collected from office records, birth certificates, and household interviews. Setting. —Participants resided in the state's most populous county and were enrolled in the Arizona Health Care Cost Containment System, a health maintenance organization—oriented Medicaid demonstration project. Subjects. —Random sample of 308 Mexican-American mother-infant dyads and 312 non-Hispanic white mother-infant dyads. The women were enrolled before the sixth month of pregnancy and for 60 days post partum; their infants were continuously enrolled throughout their first year. Outcome Measures. —Timing and number of prenatal visits and a modified Kessner Index, postpartum visits, number and purpose of office visits during the infants' first year, and immunizations received. Results. —Mexican Americans averaged fewer prenatal visits than non-Hispanic whites (8.6 vs 10.2 visits) and were less likely to have "adequate" care (41.1% vs 52.8%). Both groups of mothers are well below the 68% of women nationally who receive adequate prenatal care. Controlling for important socioeconomic status and cultural characteristics, ethnicity had a strong independent effect on the number of prenatal visits and adequacy of prenatal care. Mexican-American infants made fewer visits (8.2 vs 9.8) and completed fewer age-appropriate immunizations than non-Hispanic whites. Conclusions. —Health insurance and a regular source of care are insufficient conditions for ensuring adequate use of maternal and child health services by Mexican-American Medicaid enrollees. Factors associated with their less frequent use of these preventive health services include higher numbers of children, transportation problems, and less assistance from their support system. ( JAMA . 1994;272:297-304)
Electrochemical Sulfur Treatments of GaAs Using Na2S and (NH4)2S Solutions: A Surface Chemical Study

Chemical sulfur treatments of GaAs have been shown to improve the GaAs surface electronic properties. These treatments result in lower surface state density, lower surface recombination velocity, and shifting or unpinning of the Fermi level, in addition to improvement in the performance of devices. However, there is still considerable controversy regarding the chemical nature of the surface film which results from this chemical sulfidation. It has been shown that this film is not stable chemically and electronically. The improved surface electronic properties decay with time and are sensitive to the chemical environment of the material. In this study, using surface infrared reflection spectroscopy (SIRS) and x-ray photoelectron spectroscopy (XPS), we have investigated the electrochemical sulfidation of GaAs as a possible new method to produce a GaAs surface that is stable chemically and electronically. We have found that anodic treatments with Na 2 S and (NH 4 S solutions result in the removal of the pre-existing oxide of GaAs and the formation of films comprising sulfur, sodium carbonate, ammonium thiosulfate, and sulfide and sulfur-oxygen compounds of arsenic. Rinsing the GaAs with water removes the bulk of the film, leaving behind a surface on which only arsenic sulfide was detected.
Ultimate Tensile Properties of Elastomers. II. Comparison of Failure Envelopes for Unfilled Vulcanizates

The tensile stress‐at‐break σb (based on the initial cross‐sectional area) and the corresponding ultimate extension ratio λb of unfilled vulcanizates of silicone, hydrofluorocarbon (Viton B), butyl (both sulfur‐cured and resin‐cured), and natural rubber were determined at many strain rates and temperatures; the latter ranged from slightly above the glass transition temperature Tg, up to a temperature somewhat below that at which chemical degradation affected the results. For each vulcanizate except natural rubber, data obtained over an extended temperature range superposed to give a time‐ and temperature‐independent failure envelope on a plot of log(σb273/T) vs log(λb−1), where T is the test temperature in °K; for natural rubber, data obtained between 90° and 120°C superposed, but those at lower temperatures did not because of strain‐induced crystallization. For each vulcanizate, data at elevated temperatures gave, or tended toward, a line of unit slope on a plot of log (λbσb273/T) vs log(λb−1), where λbσ...
Evolution of Catalytic Stereoselective Olefin Metathesis: From Ancillary Transformation to Purveyor of Stereochemical Identity

There have been numerous significant advances in catalytic olefin metathesis (OM) during the past two decades. Such progress has transformed this important set of reactions to strategically pivotal processes that generate stereochemical identity while delivering molecules that cannot be easily prepared by alternative routes. In this Perspective, an analysis of the origin of the inception of bidentate benzylidene ligands for Ru-based OM catalysts is first presented. This is followed by an overview of the intellectual basis that culminated in the development of Mo-based diolates and stereogenic-at-Ru complexes for enantioselective OM. The principles accrued from the study of the latter Ru carbenes and Mo alkylidenes and utilized in the design of stereogenic-at-Mo, -W, and -Ru species applicable to enantioselective and Z-selective OM are then discussed. The influence of the recently introduced catalytic OM protocols on the design of synthesis routes leading to complex organic molecules is probed. The impact of a better understanding of the mechanistic nuances of OM toward the discovery of stereoselective catalysts is reviewed as well.
Drag measurements on a modified prolate spheroid using a magnetic suspension and balance system

Low-speed wind tunnel drag force measurements were taken on a modified prolate spheroid free of support interference. This body was tested at zero incidence in the NASA Langley 13 inch Magnetic Suspension and Balance System. This shape was one of two bodies tested to determine the drag force measuring capabilities of the 13 inch MSBS. In addition, support interference on this shape at zero incidence was quantified by using a dummy sting. The drag force calibrations and wind-on repeatability data make it possible to assess the drag force measuring capabilities of the 13 inch MSBS. Comparisons with and without the sting showed differences in the drag coefficients with the dummy sting case resulting in lower drag coefficients.
Focusing light in scattering media by ultrasonically-encoded wavefront shaping (SEWS)

Wavefront distortion in scattering media can be compensated for using optical wavefront shaping. In this technique, a spatial light modulator (SLM) is used to apply a spatially distributed phase shift to the optical field. A genetic optimization algorithm was used to obtain the SLM pattern which best focuses light within the medium. The target volume is defined by using a focused ultrasound beam to encode light travelling within the acoustic focus. The ultrasonically-encoded light is measured and used as feedback to the algorithm, which then searches for the pattern which maximizes the encoded light intensity. We call this technique ultrasonically-encoded wavefront shaping (SEWS). Using SEWS, we focused light into a scattering medium consisting of ground glass diffuser and a gelatin phantom. The optical intensity at the target was increased by 11 times over the original intensity. These results were validated using fluorescent imaging at the ultrasonic focus.
Optical Phase Imaging Using a Synthetic Aperture Phase Retrieval Technique

We perform quantitative phase imaging using phase retrieval to implement synthetic aperture imaging. Compared to digital holography, the developed technique is simpler, less expensive, and more stable.
The Effect of Imprecise Information on Incentives and Team Production

This paper links the quality (i.e. noise and bias) of productivity information and of performance measures to the organizational choice of whether or not production should occur in teams. Incentives and performance evaluation are affected by the quality of accounting information and are fundamental in the determination of organizational design. Agents have private, pre-decision information about productivity and performance is measured with both error and bias. With a perfect, private signal, agents earn informational rents, and team production is more costly because of higher productivity and thus higher rents than agents who work individually. Teams are preferred when the productivity signal is imprecise enough because with less information, agents’ rents are reduced. More importantly, the threshold of the level of precision in the productivity signal for which teams are preferred depends inversely on the amount of error in the performance measure. Increasing noise in the performance measure results in a decreased chance of reporting the high output, which reduces agents’ rents, and makes teams less costly. Further, the impact of a biased performance measurement system depends on the precision and the direction of the bias, either conservative or liberal. Increasing or changing the direction of the bias can increase the precision of the performance measure, making teams more costly. The results suggest the importance of considering the impact of the quality of information in choosing how to organize production and show that an imprecise performance measure can reduce agent’s information rents and substitute for reducing the agent’s private information.
Synthesis and Structure of Perovskite ScMnO3

The rare-earth manganites RMnO3 (R = rare earth) are a class of important multiferroics with stable hexagonal structures for small R ion radius (Sc, Lu, Yb, ...). Metastable perovskite phases of these systems possess intriguing electronically driven electrical polarization, but the synthesis of the perovskite phase for the end member ScMnO3 system has proven to be elusive. We report the structure of a new monoclinic P21/n perovskite phase of ScMnO3 synthesized from the hexagonal phase under high-pressure and high-temperature conditions. This extends the small ion region for so-called E-phase electronically driven ferroelectric manganese perovsites.
How Frequent Financial Reporting Can Cause Managerial Short-Termism: An Analysis of the Costs and Benefits of Increasing Reporting Frequency

We develop a cost�benefit tradeoff that provides new insights into the frequency with which firms should be required to report the results of their operations to the capital market. The benefit to increasing the frequency of financial reporting is that it causes market prices to better deter investments in negative net present value projects. The cost of increased frequency is that it increases the probability of inducing managerial short-termism. We analyze the tradeoff between these costs and benefits and develop conditions under which greater reporting frequency is desirable and conditions under which it is not.
Integration in Finite Terms: The Liouville Theory

The search for elementary antiderivatives leads from classical analysis through modern algebra to contemporary research in computer algorithms.