cssi/SciSciGPT-SciSciNet huggingface dataset:
Isolated oligohydramnios in the term pregnancy: Is it a clinical entity?

The aim of this study was to test the hypothesis that isolated oligohydramnios in the otherwise normal term pregnancy does not indicate fetal compromise. Women undergoing labor induction for isolated oligohydramnios between 37 and 41-6/7 weeks gestation were matched by gestational age and parity to women with normal amniotic fluid index measurements who presented in spontaneous labor. Pregnancies complicated by hypertension, diabetes, fetal anomalies, or suspected fetal growth restriction were excluded. The primary outcome variable was route of delivery. Secondary outcomes examined included presence of meconium, acidosis, low Apgar score, and NICU admission. A total of 183 women underwent induction for isolated oligohydramnios. When compared to the control group, neonatal outcome measures did not differ in the group induced for oligohydramnios. However, the women who were induced had significantly more cesarean deliveries (15.8% vs. 6.6%, P < 0.01, odds ratio 2.7). The increased need for operative delivery was not attributable to more fetal distress in the oligohydramnios group. We conclude that isolated oligohydramnios in the otherwise normal term pregnancy may not be a marker for fetal compromise, and induction of labor may not be warranted in most cases.
Possible Observational Criteria for Distinguishing Brown Dwarfs From Planets

The difference in formation process between binary stars and planetary systems is reflected in their composition, as well as orbital architecture, particularly in their orbital eccentricity as a function of orbital period. It is suggested here that this difference can be used as an observational criterion to distinguish between brown dwarfs and planets. Application of the orbital criterion suggests that, with three possible exceptions, all of the recently discovered substellar companions may be brown dwarfs and not planets. These criterion may be used as a guide for interpretation of the nature of substellar-mass companions to stars in the future.
Application of an hp-Adaptive FEM for Solving Thermal Flow Problems

Numerical results are presented for a set of forced and natural convective problems using an hp-adaptive finite element technique. The hp-adaptive model is based on mesh refinement and increasing spectral order to produce enhanced accuracy while reducing computational requirements. An a posteriori error estimator based on the L 2 norm is employed to guide the adaptation procedure. A projection algorithm is employed as the flow solver. Example test cases consisting of natural convection in a differentially heated enclosure, flow with forced convection over a backward facing step and natural convection within an enclosed partition are presented. Numerical results compare closely with published data.
Solitary, adult-onset, intraosseous myofibroma of the finger: report of a case and review of literature

Myofibroma is a rare benign neoplasm of myofibroblastic origin. It typically occurs in the skin and subcutaneous tissues of the head and neck in infants and young children as multicentric lesions known as infantile myofibromatosis. Intraosseous myofibromas are very rare and are typically destructive lesions that predominantly affect craniofacial bones in the setting of myofibromatosis. Solitary, intraosseous myofibromas in adults are exceedingly rare. Herein, we report a myofibroma involving the middle phalanx of the right index finger in a 58-year-old man who presented with a pathologic fracture. Twelve other cases of adult-onset, intraosseous myofibroma were compiled from the English language literature and integrated with this report.
Information Technology Capability, Knowledge Assets and Firm Innovation: A Theoretical Framework for Conceptualizing the Role of Information Technology in Firm Innovation

In this paper, the author presents a theoretical framework that establishes an indirect link between IT capabilities and firm innovation by characterizing the mediating role of knowledge assets: knowledge networks and knowledge capabilities. Firm innovation itself is characterized as innovation development and innovation commercialization. The search on literature of IT capability and innovation revealed a very lukewarm recognition towards firm level variables in knowledge networks, knowledge capabilities, and distinction between innovation development and commercialization. Backed up by detailed reviews of literature on innovation, strategy, and entrepreneurship, the author posits propositions linking the aforementioned constructs, and proposes a framework for future research linking IT Capability with Firm Innovation.
Nursing Professional Capital: A Qualitative Analysis

OBJECTIVE:The objective of this study was to offer qualitative support for the assertion that nurses possess professional capital.BACKGROUND:Nurses embrace professional standards and tenets that have been measured as trust and ethics. By understanding forms of capital and combining quantitative publ
Energy Relations in Complex Spectra

The manner in which the energy levels of extreme ($\mathrm{jj}$) coupling are split up by interaction of the electrons is calculated, and the results serve in special cases to determine energies in the condition intermediate between ($\mathrm{jj}$) and ($\mathrm{LS}$) coupling. Single-electron wave functions appropriate to large spin-orbit interaction are selected, and antisymmetric atomic wave functions are formed of them. With these the diagonal elements of the matrix of electrostatic interaction are reduced to combinations of radial integrals, the same integrals met by Slater in ($\mathrm{LS}$) coupling. Some configurations have only one such radial integral to express electrostatic interaction. It serves as a parameter in the extension to intermediate coupling by a method of Goudsmit. Coefficients in the general equation for the energies are determined by the energies in extreme couplings. Knowledge of electrostatic energies in ($\mathrm{jj}$) coupling, as here calculated, extends the applicability of the method to configurations having three states with the same angular momentum.
Improved Resolution of (±)-cis-2′-Hydroxy-5,9-dimethyl-6, 7-benzomorphan and Preparation of Racemic, (+)-, and (-)-cis-2-Methylcyclopropyl-2′-hydroxy-5,9-dimethyl-6,7-benzomorphan (Cyclazocine)

Abstract We report novel procedures for the efficient resolution of (±)-cis-2 -hydroxy-5, 9-dimethyl-6, 7-benzomorphan via the (-)-N-acetyl-L-glutamate and (+)-α-bromocamphor-φ-sulfonate salts, the direct N-substitution of the (+)-α-bromocamphor-φ-sulfonate salts, and the use of these methods for the synthesis of racemic, (+)-, and (-)-cyclazocine.
Diffusive Fluctuations for One-Dimensional Totally Asymmetric Interacting Random Dynamics

We study central limit theorems for a totally asymmetric, one-dimensional interacting random system. The models we work with are the Aldous–Diaconis–Hammersley process and the related stick model. The A-D-H process represents a particle configuration on the line, or a 1-dimensional interface on the plane which moves in one fixed direction through random local jumps. The stick model is the process of local slopes of the A-D-H process, and has a conserved quantity. The results describe the fluctuations of these systems around the deterministic evolution to which the random system converges under hydrodynamic scaling. We look at diffusive fluctuations, by which we mean fluctuations on the scale of the classical central limit theorem. In the scaling limit these fluctuations obey deterministic equations with random initial conditions given by the initial fluctuations. Of particular interest is the effect of macroscopic shocks, which play a dominant role because dynamical noise is suppressed on the scale we are working.
Properties of ionic liquid solvents for catalysis

Ionic liquids are good solvents for catalytic reactions. The rational selection of the appropriate ionic liquid solvent for a particular reaction requires general knowledge of the properties of ionic liquids, and the details of some properties of the specific ionic liquid solvents being considered. The solvent properties of ionic liquids that are relevant to catalysis are discussed, and sources of the values of those properties for ionic liquids are identified. A roadmap for the literature values of density, viscosity, melting and glass transition temperatures, thermal stability, empirical solvent parameters, absorption, toxicity, surface tension, heat capacity, and thermal conductivity is provided.
Leveraging belief propagation, backtrack search, and statistics for model counting

We consider the problem of estimating the model count (number of solutions) of Boolean formulas, and present two techniques that compute estimates of these counts, as well as either lower or upper bounds with different trade-offs between efficiency, bound quality, and correctness guarantee. For lower bounds, we use a recent framework for probabilistic correctness guarantees, and exploit message passing techniques for marginal probability estimation, namely, variations of the Belief Propagation (BP) algorithm. Our results suggest that BP provides useful information even on structured, loopy formulas. For upper bounds, we perform multiple runs of the MiniSat SAT solver with a minor modification, and obtain statistical bounds on the model count based on the observation that the distribution of a certain quantity of interest is often very close to the normal distribution. Our experiments demonstrate that our model counters based on these two ideas, BPCount and MiniCount, can provide very good bounds in time significantly less than alternative approaches.
Global Customer Management Programs: How To Make Them Really Work

Identifying the right business model for addressing global customers and formalizing that model into a global customer management program is a key challenge for any firm with global aspirations. The key to success is embedding the program firmly within the firm's corporate strategy. Simply leveraging domestic or regional account management into such a program will not deliver the desired results. This article presents a framework for successfully introducing a global customer management program, describing key challenges companies face at each stage of the process. It also identifies specific strategies and key principles to help firms transition to becoming truly customer-centric on a global basis.
Organic host–guest molecular assemblies

Abstract The utility of materials possessing molecular-scale porosity has been amply demonstrated by the use of inorganic zeolite frameworks as functional catalysts, separating media, and novel electronic materials. This has prompted an increase in the development of porous organic host materials capable of including guest molecules within their pores, thereby mimicking the behavior of inorganic zeolites. Such organic host–guest complexes may prove to be superior to their inorganic counterparts in some applications because they are formed spontaneously by self-assembly from molecular building blocks that can be customized through organic synthesis, yielding host structures in which the pores have precisely defined size, shape and composition. However, in order to design and synthesize host–guest complexes possessing unique and useful properties it is essential to control the assembly of molecules into preordained, desirable solid-state architectures. Understanding how molecules arrange in the solid state and using this information rationally to ‘engineer’ solid-state properties is essential to numerous technologies, including electronics, optoelectronics, sensors, information storage, and chemical separations.
The Cosmic Background Explorer (COBE)

The Cosmic Background Explorer (COBE) satellite, under study by NASA since 1976, will map the spectrum and the angular distribution of diffuse radiation from the universe over the entire wavelength range from 1 micron to 1.3 cm. It carries three instruments: a set of differential microwave radiometers (DMR) at 23.5, 31.4, 53, and 90GHz, a far infrared absolute spectrophotometer (FIRAS) covering 1 to 100 per cm, and a diffuse infrared background experiment (DIRBE) covering 1 to 300 microns. They will use the ideal space environment, a one year lifetime, and standard instrument techniques to achieve orders of magnitude improvements in sensitivity and accuracy, providing a fundamental data base for cosmology. The instruments are united by common purpose as well as similar environmental and orbital requirements. The data from all three experiments will be analyzed together, to distinguish nearby sources of radiation from the cosmologically interesting diffuse background radiations. Construction is planned to begin in 1982 for a launch in 1988.
Effects of humidity and body size on evaporative water loss in three desert rodents

Abstract 1. 1. Pulmocutaneous evaporative water loss (EWL) was studied in 3 Namib Desert rodents at three relative humidities (RH). 2. 2. Mean EWL at each RH in these species was inversely correlated with RH, and the dependence of EWL on RH was described relatively well by a linear model. 3. 3. In 2 species, EWL sample variances tended to decrease with increasing RH. 4. 4. Interspecific differences in body size were inversely correlated with mean EWL, EWL sample variances, the slopes of the regressions of EWL on RH, and the intraspecific correlations between body size and EWL. 5. 5. Body size effects on EWL appeared to interact with RH effects.
On the development of the intersection of a plane with a polytope

Define a "slice" curve as the intersection of a plane with the surface of a polytope, i.e., a convex polyhedron in three dimensions. We prove that a slice curve develops on a plane without self-intersection. The key tool used is a generalization of Cauchy's arm lemma to permit nonconvex "openings" of a planar convex chain.
Evaluating wind-following and ecosystem services for hydroelectric dams in PJM

Hydropower can provide inexpensive, flexible fill-in power to compensate for intermittent renewable generation. Policies for hydropower dams maintain multiple services beyond electric generation, including environmental protection, flood control and recreation. We model the decision of a hydroelectric generator to shift some of its power production capacity away from the day-ahead energy market into a “wind-following” service to smooth the intermittent production of wind turbines. Offering such a service imposes both private and social opportunity costs. Since fluctuations in wind energy output are not perfectly correlated with day-ahead energy prices, a wind-following service will necessarily affect generator revenues. Seasonal wind patterns produce conflicts with the goal of managing rivers for “ecosystem services”—the maintenance or enhancement of downstream ecosystems. We illustrate our decision model using the Kerr Dam in PJM’s territory in North Carolina. We simulate the operation of Kerr Dam over a three-year period that features hydrologic variability from normal water years to extreme drought conditions. We use an optimization framework to estimate reservation prices for Kerr Dam offering wind-following services in the PJM market. Wind-following may be profitable for Kerr Dam at low capacity levels during some time periods if ecosystems services are neglected and if side payments, or reserves-type payments, are provided. Wind-following with ecosystem services yields revenue losses that typically cannot be recovered with reserves market payments. Water release patterns are inconsistent with ecosystem-services goals when Kerr Dam dedicates significant capacity to wind-following, particularly in drought years.
Non-monotonic hydrodynamic lift force on highly extended polymers near surfaces

The hydrodynamic lift force that polymers experience near boundaries is known to be a crucial element when considering rheological flows of dilute polymer solutions. Here we develop a theory to describe the hydrodynamic lift force on extended polymers flowing near flat surfaces. The lift force is shown to display a non-monotonic character increasing linearly with the distance to the wall Z in the near-surface regime defined as Z L we recover the well-known far-field result in which the force decays as Z−2. Our analytical theory has important implications in understanding adsorption, desorption, and depletion layers of highly extended objects in flow.
Diastereoselective Palladium-Catalyzed α-Arylation of 4-Substituted Cyclohexyl Esters

A diastereoselective palladium-catalyzed arylation of 4-substituted cyclohexyl esters has been developed. The reaction proceeds at room temperature in the presence of [(t-Bu3P)PdBr]2 providing products in up to 37:1 dr.
RNA structure characterization from chemical mapping experiments

Despite great interest in solving RNA secondary structures due to their impact on function, it remains an open problem to determine structure from sequence. Among experimental approaches, a promising candidate is the “chemical modification strategy”, which involves application of chemicals to RNA that are sensitive to structure and that result in modifications that can be assayed via sequencing technologies. One approach that can reveal paired nucleotides via chemical modification followed by sequencing is SHAPE, and it has been used in conjunction with capillary electrophoresis (SHAPE-CE) and high-throughput sequencing (SHAPE-Seq). The solution of mathematical inverse problems is needed to relate the sequence data to the modified sites, and a number of approaches have been previously suggested for SHAPE-CE, and separately for SHAPE-Seq analysis. Here we introduce a new model for inference of chemical modification experiments, whose formulation results in closed-form maximum likelihood estimates that can be easily applied to data. The model can be specialized to both SHAPE-CE and SHAPE-Seq, and therefore allows for a direct comparison of the two technologies. We then show that the extra information obtained with SHAPE-Seq but not with SHAPE-CE is valuable with respect to ML estimation.
Inertial energy distribution error control for optimal wind-shear penetration

The principle of inertial energy distribution error control for optimal airplane microburst wind-shear penetration was developed, and a controller based on this principle was tested for its robustness in a realistic environment. A Monte Carlo approach together with a nonlinear simulation of a takeoff flight condition was used to evaluate system performance. Statistical models for the microburst strength, size, and location were used for the Monte Carlo simulation. A microburst-specific controller, based on a minimax height-loss performance index, was used in the Monte Carlo simulation as a reference controller. These trajectory results were compared with those of the controller based on an inertial energy distribution error performance index. The results obtained demonstrated two important concepts: 1) It is important to distribute inertial energy error equally between potential energy and inertial kinetic energy of the airplane system to minimize height losses. 2) Minimization of height loss results in maintaining an approximately constant inertial speed.
Domain wall fermions with exact chiral symmetry

We show how the standard domain wall action can be simply modified to allow arbitrarily exact chiral symmetry at a finite fifth dimensional extent. We note that the method can be used for both quenched and dynamical calculations. We test the method using smooth and thermalized gauge field configurations. We also make comparisons of the performance (cost) of the domain wall operator for spectroscopy compared to other methods such as the overlap-Dirac operator and find both methods are comparable in cost.
Ground-based observations of the Jovian ring and inner satellites☆

Abstract Ground-based 0.9-μm observations of the Jovian ring and inner satellites are reported. The ring observations substantially confirm those obtained by the Voyager spacecraft. The first ground-based detection of 1979J2 suggests a geometric albedo of ∼0.10 and a new value for its orbit period of 16 hr 11 min 23.5 ± 0.5 sec.
Impact of Land-Surface Moisture Variability on Local Shallow Convective Cumulus and Precipitation in Large-Scale Models

Numerical experiments using state-of-the-art high-resolution mesoscale cloud model showed that land-surface moisture significantly affects the timing of onset of clouds and the intensity and distribution of precipitation. In general, landscape discontinuity enhances shallow convective precipitation. Two mechanisms that are strongly modulated by land-surface moisture-namely, random turbulent thermal cells and organized sea-breeze-like mesoscale circulations-also determine the horizontal distribution of maximum precipitation. However, interactions between shallow cumulus and land-surface moisture are highly nonlinear and complicated by different factors, such as atmospheric thermodynamic structure and large-scale background wind. This analysis also showed that land-surface moisture discontinuities seem to play a more important role in a relatively dry atmsophere, and that the strongest precipitation is produced by a wavelength of land-surface forcing equivalent to the local Rossby radius of deformation. A general trend between the maximum precipitation and the normalized maximum latent heat flux was identified. In general, large values of mesoscale latent heat flux imply strongly developed mesoscale circulations and intense cloud activity, accompanied by large surface latent heat fluxes that transport more water vapor into the atmosphere.
Transchromatic generalized character maps

The generalized character map of Hopkins, Kuhn, and Ravenel [9] can be interpreted as a map of cohomology theories beginning with a height n cohomology theory E and landing in a height 0 cohomology theory with a rational algebra of coefficients that is constructed out of E . We use the language of p-divisible groups to construct extensions of the generalized character map for Morava E -theory to every height between 0 and n .
Conditional independence in uncertainty theories

This paper introduces the notions of independence and conditional independence in valuation-based systems (VBS). VBS is an axiomatic framework capable of representing many different uncertainty calculi. We define independence and conditional independence in terms of factorization of the joint valuation. The definitions of independence and conditional independence in VBS generalize the corresponding definitions in probability theory. Our definitions apply not only to probability theory, but also to Dempster-Shafer's belief-function theory, Spohn's epistemic-belief theory, and Zadeh's possibility theory. In fact, they apply to any uncertainty calculi that fit in the framework of valuation-based systems.
Shifts between Automobile, Bus, and Bicycle Commuting in an Urban Setting

AbstractIn an urban setting, investments in bicycle and transit modes are expected to reduce automobile vehicle miles traveled. In reality, these benefits might be lower than expected if users simply shift between nonautomobile modes. This article investigates modal shifts among automobile, bus, and bicycle use in students commuting to the University of Wisconsin-Milwaukee (UWM) in 2008 and 2012, when a few changes were made to the local transportation system. The authors found that a significant decline in automobile mode share was associated with a significant increase in bicycle mode share, suggesting that bicycling replaced certain automobile commuting trips. Analysis by distance revealed nuances in mode substitution. There were significant increases in bicycle commuting for students living between 1.6 and 15.9 km (1.0 and 9.9 miles) from campus. However, the increases in bicycling for students living between 1.6 and 3.1 km (1.0 and 1.9 miles) corresponded with decreases in bus rather than automobile ...
Killing spinors and supersymmetry on AdS

Abstract In this paper we construct several supersymmetric theories on AdS 5 background. We discuss the proper definition of the Killing equation for the symplectic Majorana spinors required in AdS 5 supersymmetric theories. We find that the symplectic Killing spinor equation involves a matrix M in the USp(2 N ) indices whose role was not recognized previously. Using the correct Killing spinors we explicitly confirm that the particle masses in the constructed theories agree with the predictions of the AdS/CFT correspondence. Finally, we establish correct O( d − 1,2) isometry transformations required to keep the Lagrangian invariant on AdS d .
The Chemical Compositions of Stars with Planets: A Review

A number of trends among the properties of exoplanets have become evident in the years since the first one was announced in 1995. One particularly interesting trend began to emerge in 1997: the incidence of giant planets correlates with the metallicity of the host star. This has since been established with a high degree of statistical significance by several research groups. Other, more subtle trends are beginning to appear as the sample size continues to grow and the statistics improve. I review the state of our knowledge concerning the observed compositional trends and their possible causes and suggest several research directions.
The Transition between Nonorthogonal Polarization Modes in PSR B2016+28 at 1404 MHz

Polarization observations of the radio emission from PSR B2016+28 at 1404 MHz reveal properties that are consistent with two very different interpretations of the pulsar's viewing geometry. The pulsar's average polarization properties show a rapid change in position angle (P.A.) near the pulse center, suggesting that the observer's sight line nearly intersects the star's magnetic pole. But single-pulse polarization observations of the pulsar show nearly orthogonal modes of polarization following relatively flat and parallel P.A. trajectories across the pulse, suggesting that the sight line is far from the pole. Additionally, P.A. histograms reveal a modal connecting bridge of unknown origin, joining the modal P.A. trajectories over much of the pulse and following the rapid P.A. change shown in the average data. The nonorthogonality of polarization modes is incorporated in a statistical model of radio polarization to account for the deviations from mode orthogonality that are observed in the pulsar. The model is used to interpret the rapid P.A. change and modal connecting bridge as a longitudinally resolved transition between modes of nonorthogonal polarization. Thus, the modal P.A. trajectories are argued to reflect the pulsar's true viewing geometry. This interpretation is consistent with the pulsar's morphological classification, preserves the Radhakrishnan & Cooke model of pulsar radio emission, and avoids the complication that the modal connecting bridge might be produced by some other emission mechanism. The statistical model's ability to simulate the rich variety of polarization properties observed in the emission lends additional support to the model's applicability and its underlying assumption that the polarization modes occur simultaneously.
Cesium Beam Atomic Time and Frequency Standards

In recognition of the October 1964 declaration of the International Committee of Weights and Measures that the physical measurement of time be based on a particular transition between two hyperfine levels in the ground state of cesium 133, a review of the characteristics of cesium beam atomic frequency standards is presented. This article discusses the general requirements for frequency and time standards, advantages offered by the atomic standard as compared to astronomical standards, various other atomic standards in brief, the operating principles of cesium standards, measures of performance, error sources in cesium standards, characteristics of several standards in current operation, comparison of cesium standards, and atomic time standards derived from atomic frequency standards.
Multiplicities and a Dimension Inequality for Unmixed Modules

Abstract We prove the following result, which is motivated by the recent work of Kurano and Roberts on Serre's positivity conjecture. Assume that (R, m ) is a local ring with finitely generated module M such that R/Ann(M) is quasi-unmixed and contains a field, and that p and q are prime ideals in the support of M such that p is analytically unramified, p + q = m and e(M p ) = e(M). Then dim R / p + dim R / q ≤ dim M . We also prove a similar theorem in a special case of mixed characteristic. Finally, we provide several examples to explain our assumptions as well as an example of a noncatenary local domain R with prime ideal p such that e(Rp) > e(R) = 1.
Reduced arithmetically Gorenstein schemes and simplicial polytopes with maximal Betti numbers

Abstract An SI-sequence is a finite sequence of positive integers which is symmetric, unimodal and satisfies a certain growth condition. These are known to correspond precisely to the possible Hilbert functions of graded Artinian Gorenstein algebras with the weak Lefschetz property, a property shared by a nonempty open set of the family of all graded Artinian Gorenstein algebras having a fixed Hilbert function that is an SI sequence. Starting with an arbitrary SI-sequence, we construct a reduced, arithmetically Gorenstein configuration G of linear varieties of arbitrary dimension whose Artinian reduction has the given SI-sequence as Hilbert function and has the weak Lefschetz property. Furthermore, we show that G has maximal graded Betti numbers among all arithmetically Gorenstein subschemes of projective space whose Artinian reduction has the weak Lefschetz property and the given Hilbert function. As an application we show that over a field of characteristic zero every set of simplicial polytopes with fixed h -vector contains a polytope with maximal graded Betti numbers.
Effect of 2 stitches vs 1 stitch on the prevention of preterm birth in women with singleton pregnancies who undergo cervical cerclage.

Objective This study investigates whether 2 cerclage stitches are more effective than 1 stitch in the prevention of preterm birth. Study Design This is a retrospective cohort study of 150 singleton pregnancies that underwent cervical cerclage. Gestational age at delivery and clinical characteristics were compared. Results One hundred twelve patients (74.7%) received 1 stitch, and 38 patients (25.3%) received 2 stitches. There were no baseline differences between the groups. Analysis showed no significant difference in gestational age at delivery between the 1 vs 2 cerclage groups overall (median, 38.0 vs 38.3 weeks of gestation, respectively; P = .356) or for a given gestational age cut-off ( P = .727]; P = .823]; P = .179]). Conclusion This study shows no measurable benefit to the placement of 2 stitches over 1 stitch during cervical cerclage in singleton pregnancies; however, further study of preterm birth at
Neutral CH and cationic CH donor groups as anion receptors.

The design and synthesis of anion selective receptors and chemosensors continues to attract considerable interest within the supramolecular community. In recent years, increasing attention has focused on the use of neutral and cationic CH hydrogen bond donors as anion recognition elements. Over the last five years, motifs that support CH⋯X (X = anion) hydrogen bonds have been actively used in various shape persistent macrocycles, foldamers and “molecular machines”. This tutorial review highlights recent developments in host–guest chemistry based on the use of neutral and cationic CH hydrogen bond donors. Also discussed are various structural classifications, including alkyl CH, phenyl CH, triazole-based CH, imidazolium (CH)+ and triazolium (CH)+ hydrogen bond donor systems.
Strategies for Weather-Dependent Data Acquisition

A strategy for data acquisition from a very distant spacecraft is presented, when the system performance can be severely degraded by the earth's weather due to the high microwave frequency being used. Two cases are considered, one in which there is a certain minimum data rate to be maintained and one in which there is not. The goal is to maximize expected data return, where we assume that there are always new data, or a backlog of old data, that can be sent if conditions are favorable. When there is no minimum rate to be maintained, the optimum strategy is typically the greedy strategy, which always transmits at that single rate which maximizes the expected data returned. If there is a minimum data rate which we strive to maintain even in adverse conditions, the optimum strategy transmits simultaneously at the minimum or base data rate and typically at a bonus data rate. We use a coding system designed for the bandwidthconstrained degraded broadcast channel. The optimum version of this system can, under realistic assumptions, save on the order of 5 dB over the conservative strategy of just transmitting at a single lower data rate.
Measuring rate constants for reactions of the simplest Criegee intermediate (CH2OO) by monitoring the OH radical.

While generating the CH2OO molecule by reacting CH2I with O2, significant amounts of the OH radical were observed by laser-induced fluorescence. At least two different processes formed OH. A fast process was probably initiated by a reaction of vibrationally hot CH2I radicals. The second process appeared to be associated with the decay of the CH2OO molecule. The addition of molecules known to react with CH2OO increased the observed decay rates of the OH signal. Using the OH signals as a proxy for the CH2OO concentration, the rate constant for the reaction of hexafluoroacetone with CH2OO was determined to be (3.33 ± 0.27) × 10–11 cm3 molecule–1 s–1, in good agreement with the value measured by Taatjes et al.1 The rate constant for the reaction of SO2 with CH2OO, (3.53 ± 0.29) × 10–11 cm3 molecule–1 s–1, showed no pressure dependence over the range of 50–200 Torr and was in agreement with the value at 4 Torr reported by Welz et al.2
Heliospheric 2-3 kHz radio emissions and their relationship to large Forbush decreases

Two intense heliospheric 2-3 kHz radio emission events have been observed by Voyagers 1 and 2, the first in 1983-84 and the second in 1992-93. These radio emission events occurred about 400 days after large Forbush decreases in mid-1982 and mid-1991. Since Forbush decreases are indicative of a strong interplanetary shock propagating outward through the heliosphere, this temporal relationship provides strong evidence that the radio emissions are triggered by the interaction of a shock with one of the outer boundaries of the heliosphere. From the travel time and the known speed of the shock, the distance to the interaction region can be estimated and is well beyond 100 AU. At this great distance the plasma frequency at the terminal shock (100 to 200 Hz) is believed to be too small to explain the observed emission frequencies, which extend up to 3.6 kHz. For this reason, we have proposed that the interaction takes place at or near the heliopause, where remote sensing measurements show that the plasma frequency is in a suitable range (approximately 3 kHz) for explaining the radio emission. From the travel time and shock propagation speed, the radial distance to the heliopause has been calculated for various candidate solar events. After taking into account the likely deceleration of the shock, the heliopause is estimated to be in the range from about 110 to 160 AU.
A SPECTROSCOPIC BINARY AT THE M/L TRANSITION

We report the discovery of a single-lined spectroscopic binary with an ultracool dwarf (UCD) primary with a spectral type between M8 and L0.5. This system was discovered during the course of an ongoing survey to monitor L dwarfs for radial velocity variations and is the first known small-separation (a < 1 AU) spectroscopic binary among dwarfs at the M/L transition. Based on radial velocity measurements with a typical precision of 300 m s−1, we estimate the orbital parameters of this system to be P = 246.73 ± 0.49 days, a1 sin i = 0.159 ± 0.003 AU, and M2 sin i = 0.2062(M1 + M2)2/3± 0.0034 M☉. Assuming a primary mass of M1 = 0.08 M☉ (based on spectral type), we estimate the secondary minimum mass to be M2 sin i = 0.054 M☉. With future photometric, spectroscopic, and interferometric observations it may be possible to determine the dynamical masses of both components directly, making this system one of the best-characterized UCD binaries known.
THE IMPRINT OF DISSIPATION ON THE SHAPES OF MERGER REMNANT LOSVDs

The properties of elliptical galaxies are broadly consistent with simulated remnants of gas-rich mergers between spirals, motivating more detailed studies of the imprint of this formation mechanism on the remnant distribution function. Gas has a strong impact on the non-Gaussian shapes of the line-of-sight velocity distributions (LOSVDs) of the merger remnant, owing to the embedded disk that forms out of the gas that retains its angular momentum during the merger, and the strong central mass concentration from the gas that falls to the center. The deviations from Gaussianity are effectively parameterized by the Gauss-Hermite moments h 3 and h 4, which are related to the skewness and kurtosis of the LOSVDs. We quantify the dependence of the (h 3, h 4)-v/? relations on the initial gas fraction f gas of the progenitor disks in 1:1 mergers, using Gadget-2 simulations including star formation, radiative cooling, and feedback from supernovae and active galactic nuclei. For f gas 15%, the overall correlation between h 3 and v/? is weak, consisting of a flat negatively correlated component arising from edge-on viewing angles plus a steep positively correlated part from more face-on projections. The spread in v/? values decreases toward high positive h 4, and there is a trend toward lower h 4 values as f gas increases from 0% to 15%. For f gas 20%, the (h 3, h 4)-v/? distributions look quite different?there is a tight negative h 3-v/? correlation, and a wide spread in v/? values at all h 4, in much better agreement with observations. Re-mergers of the high-f gas remnants (representing dry mergers) produce slowly rotating systems with near-Gaussian LOSVDs. We explain all of these trends in terms of the underlying orbit structure of the remnants, as molded by their dissipative formation histories.
Anomalous resistive transitions and new phenomena in hard superconductors

The value of the critical current (fc)-critical field (Hc) of cold-worked Nb, Mo-Re and Nb-Zr wires at constant temperature is not a single-valued function of the field and current direction. The previous history of a specimen during an experiment plays an important role and a measurement of the critical field-critical current value can influence the response of the specimen to subsequent measurements. Anomalous resistive transitions are observed when Ic, vs Hc, curves are determined by proceeding from low to high fields which may not occur in measurements proceeding from high to low fields. Further, it is possible to condition a specimen to enable it to reach maximum values of the critical field and critical current. This phenomenon is also encountered in the operation of superconducting solenoids. The polarity of the field and current during this treatment is found to be significant. The effects of the rate increase of the current, of rotating the Specimen in a transverse field, and of current density and temperature have also been studied.
Relational Contracts and the Value of Relationships

This article studies optimal relational contracts when the value of the relationship between contracting parties is not commonly known. I consider a principal-agent setting where the principal has persistent private information about her outside option. I show that if the principal has the bargaining power, she wants to understate her outside option to provide strong incentives and then renege on promised payments, while if the uninformed agent has the bargaining power, the principal wants to overstate her outside option to capture more surplus. I characterize how information is revealed, how the relationship evolves, and how this depends on bargaining power. (JEL C78, D82, D83, D86)
Laboratory Evaluation of In-Situ Gelled Acids for Carbonate Reservoirs

Three different commercial formulations (A, B, and C) of in-situ gelled acids are compared in detail at temperatures up to 150°F and acid concentrations from 5 to 20 wt% HCl. In-situ gelled acids are said to work by a gelation mechanism that occurs at the rock surface as the acid is spent. These acids contain a polymer, a crosslinker, and a breaker, in addition to other additives. Detailed viscosity measurements of each in-situ gelled acid were made with live, partially neutralized, and spent acid. A new experimental procedure was developed to partially neutralize the in-situ gelled acid with calcium carbonate, and then the apparent viscosity was measured as a function of shear rate in the range 1 to 3,000 s. The pH values of these samples varied from 0 to 6. Relative reaction rates with reservoir rock of the three in-situ gelled acids were compared at 100°F. Coreflood experiments were conducted with small acid volumes, so that permeability could be measured before acid breakthrough occurred. In-situ gelled acids all retarded the reaction of acid with reservoir rock, primarily as a result of the polymer present in the acid formulae. From viscosity measurements, live in-situ gelled acids A and B behaved more like gelled acids. Their viscosity in live acid was significantly higher than that of Acid C. In spent acid, the viscosity of Acid C was higher than that of Acids A or B. Acid C was most effective at initial HCl concentrations of 5 and 10 wt% at 100 and 150°F. Acids A and B were effective only at an initial HCl concentration of 10 wt% and 100°F. Coreflood studies showed that the polymer and crosslinker component of in-situ gelled acids irreversibly reduced the permeability of carbonate reservoir rock. As with any spent acids, mixing spent in-situ gelled acids with seawater resulted in calcium sulfate precipitation for all three of the acid systems.
Sample size and positive false discovery rate control for multiple testing

The positive false discovery rate (pFDR) is a useful overall mea- sure of errors for multiple hypothesis testing, especially when the underlying goal is to attain one or more discoveries. Control of pFDR critically depends on how much evidence is available from data to distinguish between false and true nulls. Oftentimes, as many aspects of the data distributions are unknown, one may not be able to obtain strong enough evidence from the data for pFDR control. This raises the question as to how much data are needed to attain a target pFDR level. We study the asymptotics of the minimum number of observations per null for the pFDR control associated with multiple Studentized tests and F tests, especially when the differences between false nulls and true nulls are small. For Studentized tests, we con- sider tests on shifts or other parameters associated with normal and general distributions. For F tests, we also take into account the effect of the num- ber of covariates in linear regression. The results show that in determining the minimum sample size per null for pFDR control, higher order statistical properties of data are important, and the number of covariates is important in tests to detect regression effects.
Wavefront control in space with MEMS deformable mirrors for exoplanet direct imaging

To meet the high contrast requirement of 1×10 −10 to image an Earth-like planet around a sun-like star, space telescopes equipped with coronagraphs require wavefront control systems. Deformable mirrors (DMs) are a key element of a wavefront control system, as they correct for imperfections, thermal distortions, and diffraction that would otherwise corrupt the wavefront and ruin the contrast. The goal of the CubeSat DM technology demonstration mission is to test the ability of a microelectromechanical system (MEMS) DM to perform wavefront control on-orbit on a nanosatellite platform. We consider two approaches for an MEMS DM technology demonstration payload that will fit within the mass, power, and volume constraints of a CubeSat: (1) a Michelson interferometer and (2) a Shack-Hartmann wavefront sensor. We clarify the constraints on the payload based on the resources required for supporting CubeSat subsystems drawn from subsystems that we have developed for a different CubeSat flight project. We discuss results from payload laboratory prototypes and their utility in defining mission requirements.
Leggett-Rice Systems in Harmonic Traps

We present two resugts concerning the spin (or pseudo spin) dynamics of trapped quantum gases in the hydrodynamic regime described by the Leggett equations. First, we apply perturbation theory to extend the “bounded diffusion” description to trapped systems for small field inhomogeneities. Second, we study the formation of long-lived domains with a numerical stability analysis of the lowest-lying longitudinal diffusive modes. We also use computer simulations of π/2-pulse experiments to determine the range of experimental parameters where the formation of domains can be observed.
A framework for robust mobile robot systems

Fielded mobile robot systems will inevitably suffer hardware and software failures. Failures in a single subsystem can often disable the entire robot, especially if the controlling application does not consider such failures. Often simple measures, such as a software restart or the use of a secondary sensor, can solve the problem. However, these fixes must generally be applied by a human expert, who might not be present in the field. In this paper, we describe a recovery-oriented framework for mobile robot applications which addresses this problem in two ways. First, fault isolation automatically provides graceful degradation of the overall system as individual software and hardware components fail. In addition, subsystems are monitored for known failure modes or aberrant behavior. The framework responds to detected or immanent failures by restarting or replacing the suspect component in a manner transparent to the application programmer and the robot's operator.
Isolation and Synthesis of Dibenzocyclooctadiene Lignans: (±)‐Schizandrin and Its Analogues

Abstract Simple isolation of (±)‐schizandrin (1) and preparation of its analogues (6–8) via acylation of (±)‐schizandrin (1) are described. The key strategy in the synthesis involves the catalytic acylation reaction of 1 with several acylating reagents.
Collisional dark matter and scalar phantoms

Abstract As has been previously proposed, a minimal modification of the standard SU (3)× SU (2)× U (1) theory provides a viable dark matter candidate. Such a particle, a scalar gauge singlet, is naturally self-interacting — making it of particular interest given recent developments in astrophysics. We review this dark matter candidate, with reference to the parameter ranges currently under discussion.