cssi/SciSciGPT-SciSciNet huggingface dataset:
A Re-examination of the Motives and Gains in Joint Ventures

We distinguish between horizontal and vertical joint ventures, and find correspondingly different valuation effects. Horizontal joint ventures create synergistic gains that are shared by the partners. In contrast, vertical joint ventures generate gains only for suppliers. This is similar to the pattern we find for simple contracts, which suggests economic similarities between vertical joint ventures and contracts. Analyzing firms' choices between these contracting options, we find that firms choose vertical joint ventures over simple contracts when potential hold-up problems are severe and when suppliers face finance constraints. The results do not support a risk-sharing motive for joint ventures.
Periodontology and pregnancy: An overview of biomedical and epidemiological evidence

Women are particularly susceptible to developing gingival problems during pregnancy. In addition, periodontal disease in pregnant women may lead to adverse outcomes for both mother and infant, which have serious clinical and public health implications. Both scenarios have been extensively researched, helping to bring attention to pregnant women as an important and vulnerable population as it concerns periodontal health. The increase in gingival inflammation caused by hormonal changes in pregnant women is undisputed and has been studied and documented since the 1960s, although the exact etiology is not fully understood. The relationship between periodontal disease during pregnancy and adverse pregnancy outcomes is less substantiated, because of conflicting evidence. This review of the biomedical and epidemiologic literature provides an overview of both sides of this relationship and examines the potential mechanisms for developing periodontal disease during pregnancy and the proposed mechanisms by which periodontal disease leads to adverse pregnancy outcomes.
Operation Cool Shade

Trees do more than just decorate your yard. They can actually help you save money. Studies show that proper shading of the home can reduce energy consumption by as much as 20 percent. In Tucson, the Pima County Cooperative Extension has joined with Trico Electric Cooperative to distribute shade trees at reduced prices to residents for energy conservation. The program, known as "Operation Cool Shade," began in 1997 when Trico Electric Cooperative and Pima County Extension began distributing shade trees in neighborhoods. A requirement of the program was that trees be planted in locations around the house to ensure maximum shading. The residents received training from Cooperative Extension on correct placement, planting and care of trees, according to John Begeman, urban horticulture agent. The trees selected for distribution in the past have included desert willow, eldarica pine, blue palo verde, mesquite and live oak. Trico customers are eligible to receive up to three five -gallon trees at about $5 each. Master Gardeners were trained to conduct sessions for program participants on the correct selection, placement, planting and care of shade trees. Four programs were conducted by the master gardener volunteers. In addition, master gardeners staffed a tree planting and care answer booth at the tree distribution day conducted by Trico Electric Cooperative's headquarters in Tucson. Trico employees conducted follow up inspections to ensure that trees were planted in the pre -determined locations and that the trees reMesquite tree in Tucson neighborhood
Reflections on trust: trust assurance by dynamic discovery of static properties

Static analyses allow dangerous code to be rejected before it runs. The distinct security concerns of code providers and end users necessitate that analysis be performed, or at least confirmed, during deployment rather than development; examples of this approach include bytecode verification and proof-carrying code. The situation is more complex in multi-party distributed systems, in which the multiple web services deploying code may have their own competing interests. Applying static analysis techniques to such systems requires the ability to identify the codebase running at a remote location and to dynamically determine the static properties of a codebase associated with an identity. In this paper, we provide formal foundations for these requirements. Rather than craft special-purpose combinators to address these specific concerns, we define a reflective, higher-order applied pi calculus and apply it. We treat process abstractions as serialized program files, and thus permit the direct observation of process syntax. This leads to a semantics quite different from that of higher-order pi or applied pi.
Electromotive force studies in aqueous solutions at elevated temperatures—XIII: the thermodynamic properties of HClNaClMgCl2 mixtures

Abstract E.M.F. measurements of the cell Pt−H 2 (p=1)| HCl (m 2 ), NaCl (m 3 ), MgCl 2 (m 4 )| AgCl, Ag have been combined with isopiestic and glass electrode measurements of the system NaClMgCl2 to calculate the activity coefficients of each of the electrolytes in aqueous HClNaClMgCl2 mixtures. The activity coefficient behaviour in this system is compared with that observed in the previously studied HClCsClBaCl2 system.
Bear Bryant : Symbol for an embattled south

En 1961, l'equipe de football de l'universite d'Alabama remporta la finale du Sugar Bowl. Cette victoire fut recuperee politiquement par le depute Frank Boykin, qui esperait ainsi ameliorer l'image negative du Sud et s'octroyer des appuis exterieurs pour faire face a la lutte des droits civiques. L'entraineur de l'equipe, Paul « Bear » Bryant devint un puissant symbole de fierte et de vitalite culturelle pour les blancs du sud dans une periode de profond changement social. Le role du football universitaire comme pouvoir talismanique est ici mis largement en avant, ainsi que l'histoire de Bear Bryant qui relate la vie d'un homme auquel on confia le role de defenseur de la suprematie blanche en 1961, puis qui devint vingt ans plus tard un hero national pour avoir integre des etudiants noirs dans son equipe universitaire. L'image de Bryant, que ce soit au niveau national ou federal, reflete le besoin societal d'avoir des heros qui incarnent les valeurs culturelles dominantes
Evolution of brown carbon in wildfire plumes

Particulate brown carbon (BrC) in the atmosphere absorbs light at subvisible wavelengths and has poorly constrained but potentially large climate forcing impacts. BrC from biomass burning has virtually unknown lifecycle and atmospheric stability. Here, BrC emitted from intense wildfires was measured in plumes transported over 2 days from two main fires, during the 2013 NASA SEAC4RS mission. Concurrent measurements of organic aerosol (OA) and black carbon (BC) mass concentration, BC coating thickness, absorption Angstrom exponent, and OA oxidation state reveal that the initial BrC emitted from the fires was largely unstable. Using back trajectories to estimate the transport time indicates that BrC aerosol light absorption decayed in the plumes with a half-life of 9 to 15 h, measured over day and night. Although most BrC was lost within a day, possibly through chemical loss and/or evaporation, the remaining persistent fraction likely determines the background BrC levels most relevant for climate forcing.
AXIOMS FOR DYNAMIC PROGRAMMING

This paper describes an abstract framework, called valuation network (VN), for representing and solving discrete optimization problems. In VNs, we represent information in an optimization problem using functions called valuations. Valuations represent factors of an objective function. Solving a VN involves using two operators called combination and marginalization. The combination operator tells us how to combine the factors of the objective function to form the global objective function (also called joint valuation). Marginalization is either maximization or minimization. Solving a VN can be described simply as finding the marginal of the joint valuation for the empty set. We state some simple axioms that combination and marginalization need to satisfy to enable us to solve a VN using local computation. We describe a fusion algorithm for solving a VN using local computation. For optimization problems, the fusion algorithm reduces to non-serial dynamic programming. Thus the fusion algorithm can be regarded as an abstract description of the dynamic programming method, and the axioms can be viewed as conditions that permit the use of dynamic programming. Subject classification: Dynamic programming: theory, algorithm.
Absence of a 5S RNA complnent in the mitochondrial ribosomes of Neurospora crassa.

RIBOSOME-BOUND, low molecular weight RNA, distinct from tRNA, was first observed in E. coli by Rosset and Monier1. This RNA, which has a sedimentation coefficient of about 5S, is now considered to be a universal component of ribosomes. We report here our attempts to find low molecular weight RNAs other than tRNA in mitochondria of Neurospora. Our evidence suggests that the mitochondrial ribosomes of this organism lack a 5S RNA component.
A simple, fast numerical method for the solution of a wide variety of electrochemical diffusion problems

Abstract A numerical analysis technique known as orthogonal collocation, which has found considerable use in solving linear and non-linear partial differential equations in chemical engineering, is applied to a variety of boundary value problems found in chronoamperometry. Due to the properties of the collocation functions, the technique requires very little implicit mathematics and results in a large savings in computer time over the common digital simulation technique or the Crank-Nicholson finite difference scheme. Simulation of a new boundary value problem requires only a few operations of calculus and matrix algebra and alteration of very few program statements. The computer program employed is quite simple and is composed almost entirely of highly efficient library subroutines. Due to the nature of the orthogonal polynomials used to represent the spatial dependence of concentration, the trial function exactly fits the partial differential equation at the collocation points and transforms it into a set of simultaneous first order ordinary differential equations. These equations are solved numerically in about 5 s on a CDC 6600 to give accurate working curves (≈0.1% error or less) for the e.c.e. and for first and second order disproportionation mechanisms at a planar electrode.
A cost-benefit analysis of a cardiovascular disease prevention trial, using folate supplementation as an example.

OBJECTIVES: This study illustrates a cost-benefit analysis of clinical trial design, using as an example a trial of folate supplementation to prevent cardiovascular disease. METHODS: Bayesian statistical and decision-analytic techniques were used to estimate the cost-benefit and sample size of a placebo-controlled trial of folate targeted to US citizens, aged 35 to 84 years, with elevated serum homocysteine levels. The main end point is event-free survival (i.e., survival without new ischemic heart disease or stroke) at 5 years. RESULTS: Because the screening cost and annual cost and inconvenience of taking folate is small compared with the consequences of stroke, ischemic heart disease, or death, the increase in 5-year event-free survival with folate that should compel the use of folate is just 1.1%. The sample size per group needed to establish this level of folate's medical effectiveness is estimated to be 17310. Such a trial would provide an expected societal cost-benefit savings exceeding $11 billion...
Relative integral bases over a Hilbert class field

Abstract Let K be a number field, H its Hilbert class field and L a Galois extension of K containing H. In this paper, we prove that L|H has a relative integral basis (RIB) if the order of G=Gal(L|H) is odd or if the 2-Sylow subgroups of G are not cyclic. If the order of G is even and the 2-Sylow subgroups are cyclic we reduce the problem of the existence of a RIB to a quadratic extension of H.
A Steady-State Stratospheric Aerosol Model

This paper deals with the development of a one-dimensional steady-state stratospheric aerosol model and the subsequent perturbations caused by including the expected Space Shuttle particulate effluents in the model. Two approaches to the basic modeling effort have been made: in one, enough simplifying assumptions were introduced so that a more or less exact solution to the descriptive equations could be obtained; in the other, very few simplifications were made and a computer technique was used to solve the equations. The most complete form of the model contains the effects of sedimentation, diffusion, particle growth and coagulation. The results indicate that the model is capable of describing many aspects of the stratospheric aerosol layer, such as size distribution and the vertical profile of particles greater than 0.3 micron diameter.
Anomalous structure-activity relationships of 13-homo-13-oxarotenoids and 13-homo-13-oxadehyrorotenoids.

Cube resin, used as an insecticide/miticide and piscicide, contains in decreasing amounts rotenone (1), deguelin (2), the 6a,12a-dehydro derivatives of rotenone (3) and deguelin (4), and the newly-discovered 13-homo-13-oxa-6a,12a-dehydro analogs [referred to as oxadehydrorotenone (5) and -deguelin (6)]. These six rotenoids were compared for potency as inhibitors of NADH:ubiquinone oxidoreductase activity and for organismal toxicity to mosquito larvae, goldfish, and mice and cytotoxicity in three mammalian cell lines (Hepa 1C1C7, MCF 7, and NB 41A3). Although rotenoids 3-6 contribute very little to the overall activity of cube resin, there were two surprising aspects to the structure-activity relationships. First, 1 was 7-15-fold more active than 2 in the cytotoxicity assays of 4-day duration but not in the other systems. This difference in cytotoxicity is not due to specificity at the oxidoreductase target but instead to more extensive cytochrome P450-dependent (piperonyl butoxide-sensitive) detoxification of 2 than of 1. Second, the observed potency increase on conversion of dehydrorotenone to either rotenone or oxadehydrorotenone suggests that combining both structural changes to form cis-13-homo-13-oxarotenone (8) might result in maximal activity. Accordingly, 5 was reduced with diisobutylaluminum hydride to the trans-isomer 7 and then epimerized with aqueous pyridine to the cis-isomer 8 of the same configuration as 1. Surprisingly, 8 was much less active than 1. This is rationalized on the basis of conformational changes in the B/C ring system and decreasing dihedral angle (determined by X-ray crystallography and/or molecular modeling) between the A and D rings that follow the potency order, i.e., rotenoids 1 and 2 > oxadehydrorotenoids 5 and 6 > trans- and cis-oxarotenoids 7 and 8 > dehydrorotenoids 3 and 4. Thus, the novel oxarotenoids and oxadehydrorotenoids help define the conformation optimal for NADH:ubiquinone oxidoreductase inhibition and toxicity.
Multiplicity Reactivation as a Test for Recombination Function

Multiplicity reactivation of bacteriophage inactivated by ultraviolet light is dependent on the recombination function of either the host bacterial cell or the infecting bacteriophage. Absence of both recombination systems leads to a loss of multiplicity reactivation.
The origins and impact of primate segmental duplications

Duplicated sequences are substrates for the emergence of new genes and are an important source of genetic instability associated with rare and common diseases. Analyses of primate genomes have shown an increase in the proportion of interspersed segmental duplications (SDs) within the genomes of humans and great apes. This contrasts with other mammalian genomes that seem to have their recently duplicated sequences organized in a tandem configuration. In this review, we focus on the mechanistic origin and impact of this difference with respect to evolution, genetic diversity and primate phenotype. Although many genomes will be sequenced in the future, resolution of this aspect of genomic architecture still requires high quality sequences and detailed analyses.
Energy status in the fat body of Trichoplusia ni parasitized by the insect parasite Hyposoter exiguae

Abstract The levels of adenylate nucleotides were examined in 4th-instar Trichoplusia ni larvae 3 days after parasitization by the insect parasite Hyposoter exiguae. In general, parasitization caused a decrease in the level of ATP and increased ADP and AMP levels. These changes resulted in alteration of the adenylate kinase mass-action ratio. The overall energy status of parasitized larvae, however, as indicated by energy ratios, including the “energy charge,” was affected only slightly. The result demonstrates that the host maintained an active and viable metabolic state despite extensive alterations in physiology which occur at this stage of the parasite-host association.
Acalculous and Clostridial Cholecystitis in a Pig

A 21-month-old domestic Hanford pig (Sus scrofa domestica) in a 1-year study for experimental myocardial infarction was euthanized at the end of the study. One week earlier, the animal had symptoms and elevated clinical chemistry results suggestive of hepatobiliary disease, which resolved after medical therapy. At necropsy, the gallbladder was markedly enlarged, discolored, and had a thickened wall. Within the gallbladder, there was abundant friable green-brown material. A culture of the gallbladder luminal material yielded Clostridium perfringens type A. Histopathology of the gallbladder demonstrated multifocal areas of necrosis of varying depths, admixed with an inflammatory infiltrate that was also observed on the serosa and within the associated adipose tissue. Luminal material was composed of cellular debris and bile sludge admixed with numerous bacterial rods. Smooth-muscle hypertrophy of numerous small arterioles with narrowed lumina was observed in the gallbladder. A diagnosis of acalculous cholecystitis presumably because of ischemia of the gallbladder with secondary clostridial infection was made. To the authors' knowledge, this is the first reported case of acalculous cholecystitis with evidence of vascular compromise in a pig, as well as cholecystitis secondarily attributed to Clostridium perfringens type A.
Tracking in a Ground to Satellite Optical Link : Effects due to Lead-ahead and Aperture Mismatch

Establishing a link between a ground station and a geosynchronous orbiting satellite can be aided greatly with the use of a beacon on the satellite. A tracker, or even an adaptive optics system, can use the beacon during communications activities to correct beam pointing for atmospheric turbulence and mount jitter effects. However, the pointing lead-ahead required to illuminate the moving object and an aperture mismatch between the tracking and pointing apertures can limit the effectiveness of the correction as the sensed tilt will not be the same as the tilt required for optimal transmission to the satellite. In this paper we present an analytical model that addresses the combined impact of these tracking issues in a ground-to-satellite optical link. The analysis considers geosynchronous Earth orbit satellites as well as low Earth orbit satellites.
On the Mach- and Reynolds-Number Dependence of the Flat-Plate Turbulent Boundary Layer Wall-Pressure Spectrum

Wall-pressure measurements are performed using an array of pinhole microphones mounted into the test wall of a low noise, low turbulence flow facility. The frequency–wave-number spectra for both streamwise and spanwise directions are obtained through the spatial Fourier transformation of cross-spectral measurements in the said directions. The results of the wind-tunnel measurements reveal an interesting behavior of the low wave-number portion of the wall-pressure spectrum. Namely, this portion of the spectrum does not exhibit any Mach-number dependence for nearly incompressible flows. A low Mach-number analysis accounting for finite Reynolds-number effects is performed. This analysis shows the wall-pressure spectrum to have a leading term independent of the Mach number. The frequency dependence of the theoretical spectrum agrees well with that of the experimental spectrum. The physical mechanism for the Mach-number independence of the spectrum is attributed to a hydrodynamic dipole contribution to the wall pressure resulting from the Stokes layer induced by the turbulent eddies. The higher differential order of the viscous equations of motion allows for the existence of such Stokes layers. They have no counterpart in invisicd theories wherein no such Mach-number independence of the spectrum has been observed. A simple model problem is devised which isolates the viscous mechanism responsible for the modification of the wall pressure and the corresponding sound field. It is argued that the physical process involved is akin (albeit inversely) to that operative in the boundary-layer receptivity problem for nearly incompressible flows.
Elastic scattering of vector polarized deuterons by 4He

Abstract The vector analyzing power iT 11 for deuterons elastically scattered by 4 He has been measured for c.m. angles between 51.8° and 158.9° and deuteron energies in the range 11.5 to 17 MeV. The results show that d- α scattering is a convenient analyzer for deuteron vector polarization in the energy range investigated, since the angular dependence of iT 11 is fairly insensitive to energy and the magnitude of iT 11 is quite large at some angles.
Sobolev smoothing of SVD-based Fourier continuations

Abstract A method for calculating Sobolev smoothed Fourier continuations is presented. The method is based on the recently introduced singular value decomposition based Fourier continuation approach. This approach allows for highly accurate Fourier series approximations of non-periodic functions. These super-algebraically convergent approximations can be highly oscillatory in an extended region, contaminating the Fourier coefficients. It is shown that through solving a subsequent least squares problem, a Fourier continuation can be produced which has been dramatically smoothed in that the Fourier coefficients exhibit a prescribed rate of decay as the wave number increases. While the smoothing procedure has no significant negative effect on the accuracy of the Fourier series approximation, in some situations the smoothed continuations can actually yield increased accuracy in the approximation of the function and its derivatives.
Studies on the apparent instability of bovine kidney α-ketoglutarate dehydrogenase complex

Abstract The α-ketoglutarate dehydrogenase complex in extracts of bovine kidney and liver mitochondria is inactivated rapidly at 25 °C. This inactivation is not accompanied by loss of activity of the three component enzymes of the complex. This inactivation can be prevented by extensive washing of the mitochondria with dilute phosphate buffer prior to rupturing the mitochondria by freezing and thawing. Evidence is presented that the washings contain a protease which cleaves a peptide bond or bonds in the dihydrolipoyl transsuccinylase component of the α-ketoglutarate dehydrogenase complex, and this limited proteolysis results in dissociation of α-ketoglutarate dehydrogenase and dihydrolipoyl dehydrogenase from the transsuccinylase. The protease appears to be specific for the transsuccinylase component of the mammalian α-ketoglutarate dehydrogenase complex. It does not affect the activity of the mammalian pyruvate dehydrogenase complex or the Escherichia coli α-ketoglutarate dehydrogenase complex. The protease has been purified about 100-fold from extracts of unwashed mitochondria from bovine kidney. It requires a thiol for activity and it is not affected by treatment with diisopropyl phosphorofluoridate or phenylmethyl sulfonylfluoride. A component has been detected in highly purified preparations of the bovine kidney α-ketoglutarate dehydrogenase complex by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, which is present in trace amounts, if at all, in purified preparations of the bovine heart α-ketoglutarate dehydrogenase complex. This component is tightly bound to the transsuccinylase.
New and emerging therapies for the treatment of rheumatoid arthritis

The introduction of tumor necrosis factor (TNF) inhibitors in the late 1990s significantly changed the therapeutic approach for rheumatoid arthritis (RA). With the approval of subsequent TNF inhibitors as well as other biologic agents effective in the management of RA, the treatment paradigm has become increasingly complex. This review examines the current literature regarding the efficacy and toxicity of these and other new anti-rheumatic therapies and discusses effective therapeutic strategies for their use.
High-intensity effects in liquid crystals driven by 532-nm nanosecond laser pulses

We observed unusual high-contrast, far-field, elliptical diffraction rings in a green, linear polarized nanosecond laser beam, a phenomenon strongly dependent on the orientation of the nematic liquid crystal molecules, under the experimental conditions excluding ordinary orientational or thermal self-focusing. The threshold of the nonlinearity is modified either by changing the laser repetition rate (cumulative nature) or by adding a two-photon absorbing chromophore.
Octahedral metal carbonyls. 74. Estimates of solvent-metal bond strengths in (solvent)M(CO)5 complexes (solvent=benzene (M=Mo, W) and tetrachloromethane (M=Cr))

Abstract Desolvation in three (solv)M(CO)5 complexes (M=Cr, Mo, W; solv=solvent) produced after pulsed laser flash photolysis in solv/1-hexene mixtures takes place exclusively via dissociative mechanisms. The enthalpies of activation for solvent dissociation, which should closely approximate the solv-M bond strengths, have been determined for the η2-benzene-Mo and η2-benzene-W bonds, in which benzene likely is coordinated to the metal edge-on in a dihapto fashion, and tetrachloromethane-Cr bonds, which involve Cl-to-Cr coordination. These inferred bond strengths are compared to other reported metal-ligand (L) bond strengths derived from kinetics data in solution for LM(CO)5 complexes, and M-alkane bond strengths obtained from time-resolved photoacoustic calorimetric studies.
Repetitive multifocal paroxysmal atrial tachycardia: With cyclic Wenckebach phenomenon under observation for thirteen years

Abstract A patient with repetitive multifocal paroxysmal atrial tachycardia with cyclic Wenckebach phenomenon is described. The arrhythmia has persisted, without other physical or laboratory abnormalities, for 13 years and perhaps for about 20 years.
Critical role for transcription factor AP-2α in human trophoblast differentiation

To examine whether AP-2α is a critical component of the genetic program that directs human trophoblast differentiation, we used DNA microarray analyses to characterize the effects of a dominant-neg...
Information design considerations for improving situation awareness in complex problem-solving

The conventional techniques for task analysis derive the basic tasks that make up user actions. However, in the complex-problem solving environment, attempts to describe step-by-step actions breakdown because no single route to a solution exists. Although individual tasks can be defined, task-analysis normally results in the tasks being divorced from context. However, to support complex problem-solving, the design must place the information within the situation context and allow users to develop and maintain situation awareness.
Seasonality of Monstrilla Helgolandica Claus, 1863 (Copepoda, Monstrilloida) and the Occurrences of Other Monstrillids in Maine

ABSTRACT Sixty-five monstrillid copepods, of five species, were taken from coastal and estuarine waters of Maine from 1971 to 1980. Monstrilla helgolandica was most abundant (53 individuals) and showed marked seasonality, occurring only from January to April, at temperatures of -1.3 to 3.2°C. A single specimen of Monstrilla canadensis, which is probably the male of M. helgolandica, was found in February. Monstrilla longicornis (3 specimens) and M. longiremis (5 specimens) occurred only in summer. Monstrillopsis dubia (3 specimens) seemed to have no seasonal preference. Only M. canadensis and M. dubia have been previously reported from the Gulf of Maine.
Saharan and Asian dust: similarities and differences determined by CALIPSO, AERONET, and a coupled climate-aerosol microphysical model

Abstract. This study compares the properties of atmospheric dust from the Saharan deserts and the Asian deserts using data from CALIPSO and AERONET during 2006 and 2007 along with simulations using a coupled climate-microphysical sectional model. Saharan deserts are largely south of 30° N, while Asian ones are primarily north of 30° N, hence they experience different meteorological regimes. Saharan dust lifting occurs all year long, primarily due to subtropical weather systems. However, Asian dust is lifted mostly in spring when mid-latitude frontal systems lead to high winds. Rainfall is more abundant over Asia during the dust lifting events, leading to greater local dust removal than over the Sahara. However, most dust removal is due to sedimentation. Despite the different meteorological regimes, the same dust lifting schemes work in models for Asian and Saharan dust. The magnitudes of dust lifted in Africa and Asia differ significantly over the year. In our model the yearly horizontal dust flux just downwind of the African dust source is about 1088 Tg (10° S–40° N, 10° W) and from the Asian dust source it is about 355 Tg (25° N–55° N, 105° E) in 2007, which is comparable to previous studies. We find the difference in dust flux is mainly due to the larger area over which dust is lifted in Africa than Asia. However, Africa also has stronger winds in some seasons. Once lifted, the Saharan dust layers generally move toward the west and descend in altitude from about 7 km to the surface over several days in the cases studied. Asian dust often has multiple layers (two layers in the cases studied) during transport largely to the east. One layer stays well above boundary layer during transport and shows little descent, while the other, lower, layer descends with time. This observation contrasts with studies suggesting the descent of Saharan dust is due to sedimentation of the particles, and suggests instead it is dominated by meteorology. We find the size distributions of Asian and African dust are similar when the dust is lifted, but the mode size can differ and secondary size modes can develop probably due to differences in vertical wind velocities during transport. The single scattering albedo of African and Asian dust does differ, due primarily to the imaginary parts of the refractive indexes being different, which in turn is likely due to different dust composition. This study is a step towards a global understanding of dust and its properties.
Infant-care behavior of mothers and fathers in a communal-care primate, the cotton-top tamarin (Saguinus oedipus)

Infant care behavior was examined for 35 litters of 23 different groups of captive cotton-top tamarins. The behavior of mothers and fathers was compared to determine the effects of infant number and helper presence on each parent and to determine whether parents differed in responsiveness to infants. For young infants (1-4 weeks), the contribution of fathers to infant carrying was negatively correlated with helpers' contribution; as helpers carried more, fathers carried less. In contrast, the mothers' contribution to infant carrying was unaffected by helper contribution. Mothers carried older infants (5-8 weeks) less than did fathers, regardless of infant number or helper contribution. Fathers and mothers were equally likely to retrieve a non-harassed infant; however, fathers were more likely than mothers to retrieve an infant being harassed. These results suggest that fathers are more responsive to infants than are mothers. Mothers may limit their involvement in infant care, as has been proposed by field results, due to an energetically demanding reproductive strategy.
Casting Ceramic-Polymer Sheets

Thin ceramic structures can be efficiently formed by the tape casting process, using a doctor blade for thickness control. A concentrated suspension of the ceramic precursor powder is made in a solvent system, with a polymeric binder, a dispersing agent, and other additives. For high performance ceramic applications, a non-aqueous solvent is generally preferred. The physical chemistry background leading to this choice is discussed, particularly in regard to the competing adsorptions of solvent, dispersant, and binder. Glyceryl trioleate is shown to be a useful dispersant for such systems, allowing dense compacts to be achieved, even with submicron particle sizes. Thus a refractory powder can be fired to nearly theoretical density at practical temperatures.
A comparison of the transform and classical methods

This article compares the amount of arithmetical computation required to determine transient currents by the transform method with that required to determine the same currents by the classical method. The amount of arithmetical computation is measured by the number of times it is necessary to multiply or add two numbers. Comparison is made only for the case in which the circuits have few branches with lumped constants of resistance, inductance, and capacitance, and any advantage or disadvantage either method may have in other cases is not considered. No account is taken of the added effort necessary to acquire a working knowledge of the transform method nor of the time required to derive the transform expressions for the currents from the differential equations.
Knowledge-Based Task Planning Using Natural Language Processing for Robotic Manufacturing

Robotic alternative to many manual operations falls short in application due to the difficulties in capturing the manual skill of an expert operator. One of the main problems to be solved if robots are to become flexible enough for various manufacturing needs is that of end-user programming. An end-user with little or no technical expertise in robotics area needs to be able to efficiently communicate its manufacturing task to the robot. This paper proposes a new method for robot task planning using some concepts of Artificial Intelligence. Our method is based on a hierarchical knowledge representation and propositional logic, which allows an expert user to incrementally integrate process and geometric parameters with the robot commands. The objective is to provide an intelligent and programmable agent such as a robot with a knowledge base about the attributes of human behaviors in order to facilitate the commanding process. The focus of this work is on robot programming for manufacturing applications. Industrial manipulators work with low level programming languages. This work presents a new method based on Natural Language Processing (NLP) that allows a user to generate robot programs using natural language lexicon and task information. This will enable a manufacturing operator (for example for painting) who may be unfamiliar with robot programming to easily employ the agent for the manufacturing tasks.© 2010 ASME
A statistical theory of traffic flow on highways—IV. Semi-empirical steady state theory☆

Abstract A simple semi-empirical model of traffic flow on highways, similar to one developed by Miller, is introduced. This consists of the distribution of desired speeds for the cars entering the road and of the passing frequencies from queues going various speeds as functions of the number of cars crossing a fixed point in unit time. Equations are derived giving the time evolution of all relevant probabilities. These equations are solved formally through an expansion in powers of the number of cars crossing a fixed point in unit time. It then becomes only a straightforward algebraic problem to compute any quantity of interest as a function of the number of cars crossing a fixed point in unit time for traffic conditions in which only queues of finite lengths are important.
Displacement partitioning and arc-parallel extension in the Aleutian volcanic island arc

Abstract Convergence between the Pacific and North American plates along the Aleutian volcanic island arc is generally right-oblique; the obliquity increases from 0° in the east to nearly 90° in the west where the plate boundary becomes a transform fault zone. Preliminary results of a structural geology study of Attu Island (the most westerly U.S. island in the Aleutian chain and part of the Near Islands group) shows that the deformational structures are not directly related to the relative plate-convergence-rate vector, but to the plate-boundary-normal and -parallel components of this vector. The plate-boundary-(sub)normal component is responsible for conjugate sets of arc-(sub)parallel thrust faults and the plate-boundary-parallel component resulted in arc-parallel dextral strike-slip faults and their conjugates. However, the most penetrative structures measured in outcrop are conjugate sets of strike-slip faults and arc-perpendicular normal faults and fractures (veins and dikes) which have formed by arc-parallel extension. This extension is most likely the result of the increase of obliquity from east to west and thus the increase of the arc-parallel component of the convergence-rate vector along the Aleutian arc. These structures require that Attu Island migrated westward, possibly for as many as 1150 km.
Prospective and retrospective tests of evolutionary theories of senescence

Retrospective and prospective methods in the study of the evolution of longevity and senescence are compared. Retrospective studies can provide tests of evolutionary theories of senescence through the interpretation of evolutionary pattern demonstrated by species in nature. Patterns in longevity displayed by African rivulin fishes provide a clear and incisive example of the evolution of longevity and associated life history characters, but such tests are often difficult to find or unclear in the a posteriori interpretation of evolution that they offer. Far more experimentation of the prospective kind has been applied to testing theories of life span. Though prospective tests of evolutionary theory are compromised to a degree by the artificiality of the laboratory environment, experiments performed there are not necessarily invalid. In addition, prospective tests offer the added impetus that theoretical predictions are tested a priori. The use of Drosophila melanogaster as a laboratory model for the study of longevity has provided a number of particularly enlightening recent advances describing the number and distribution of genes controlling longevity, the metabolic pathways by which other characters are physiologically associated with life span, and even the controlling genetic elements affecting those traits. Improvements in longevity shown under programs of selective breeding may be the result of adaptations in the glycolytic pathway altering the ability to utilize the sugar sucrose as a food source.
THE EFFECT OF DIGESTIVE JUICES ON THE POTENCY OF BOTULINUS TOXIN.

Botulinus toxin resists a degree of acidity equivalent to that of the stomach even when exposed thereto for 24 hours at 37°C. It is less resistant to alkali, however, as shown by the fact that in a medium of weakly alkaline reaction its potency is reduced to less than one-tenth in 24 hours. It is unaffected by peptic and tryptic digestion. Because of its instability in mildly alkaline solutions and resistance to acid, there is reason to believe that the toxin is in the main absorbed from the upper portion of the digestive tract; that is to say, from the stomach and upper duodenum.
Radiation patterning enabled by ε-near-zero reconfigurable metamaterial lenses

We analyze and experimentally demonstrate a novel class of reconfigurable microwave lens components based on the ultrafast propagation properties and anomalous impedance matching features of arrays of thin waveguide channels operated at cut-off, which are shown to realize low-loss, e-near-zero (ENZ) metamaterials impedance matched to free-space. Using this concept, we realize a compact microwave lens that can transform cylindrical wavefronts, excited by a simple coaxial source, into arbitrary wavefront patterns, obtained by simply reconfiguring the lens output interface. We are able to experimentally observe uniform-phase, oblique, converging, and “brick” patterns. We envision applications to realize a multitude of antenna reconfigurable radome and lens designs, impedance matched to free-space independent of the excitation.
Pulmonary Valvotomy: An Alternative Method

Abstract An alternative technique of pulmonary valvotomy for patients with pulmonary atresia and intact ventricular septum is presented. The method is simpler and safer than open valvotomy with inflow occlusion or with cardiopulmonary bypass. It is more precise and controlled than closed valvotomy.
Nonequilibrium chemical potentials and free energies for enzyme-catalyzed reactions.

Using the statistical theory of nonequilibrium thermodynamics we explore the nature of nonequilibrium corrections to chemical potentials in simple enzyme-catalyzed reactions. The statistical definition of the chemical potential, which pertains to systems that are at stable steady states, is applied to the Michaelis-Menten reaction scheme in a cellular-sized compartment that communicates with out-side reservoirs. Calculations based on the kinetic parameters for hexokinase and triose phosphate isomerase show that substantial corrections to the chemical potential of product (the order of 25 mV) are possible if the reaction is sufficiently far from equilibrium. The dependence of the corrections to the chemical potentials on the size of the cellular compartment are explored, and the relevance of the corrections for understanding the thermodynamics of metabolites is discussed.
Facets with fixed defect of the stable set polytope

The stable set polytope of a graph is the convex hull of the 0-1 vectors corresponding to stable sets of vertices. To any nontrivial facet ∑ v∈V a(v)x v ≤b of this polytope we associate an integer δ, called the defect of the facet, by δ=∑ v∈V a(v)-2b. We show that for any fixed δ there is a finite collection of graphs (called “basis”) such that any graph with a facet of defect δ contains a subgraph which can be obtained from one of the graphs in the basis by a simple subdivision operation.
Oxidation products of amino acids and collagen.

Abstract Amino acids are known to react with oxidizing agents and some of the degradation products are less complex amino acids. In this study, 14 amino acids as well as fibrous corium collagen and epoxy resin-tanned collagen were reacted with a hydrogen peroxide or hydrogen peroxide-copper sulfate solution, and a number of amino acids were identified chromatographically which were not originally present. These results may explain the presence of several ninhydrin-reactive unknowns formed during hydrolysis of the product obtained by tanning fibrous corium collagen with an epoxy resin.
Surveillance Issues in a Smart Home Environment

A surveillance system for assisting the elderly in remaining independent in their familiar environment is one of the subjects interest in recent healthcare studies. When mature, it is expected that this system will have the ability to track objects that a resident may lose periodically, detect falls within the home, alert family members or healthcare professionals to abnormal behaviors. This paper addresses the early stages and issues of the development of such a system, the physical characteristics of the system that is being designed, early results, and guidance on the future work that will have to be completed in the future.
Serial noninvasive assessment of left ventricular hypertrophy and function after surgical correction of aortic regurgitation

Serial echocardiographic analyses of left ventricular hypertrophy and function, with validation of extent of shortening by first pass radionuclide angiography, was performed in 16 patients before and after surgical correction of severe aortic valve regurgitation. All patients were symptomatic (predominantly in New York Heart Association functional class III or IV) before operation but were in class I or II after operation. The preoperative pattern of eccentric hypertrophy (increased mass with normal ratio of left ventricular cross-sectional wall area to cavity area) changed immediately after operation to a pattern of concentric hypertrophy (increased mass with increased ratio of left ventricular cross-sectional wall area to cavity area) because of a significant reduction in chamber size and increase in wall thickness. On late follow-up (9 to 35 months, average 15 months after operation), the hypertrophy lessened significantly, the cross-sectional area of the ventricular wall decreasing to 21.1 ± 5.4 (mean ± standard deviation) cm2 from a preoperative average of 31.6 ± 4.8 cm2 (P < 0.01), and the ratio of wall area to cavity area was once again normal. In the same period, left ventricular enddiastolic diameter decreased from 6.52 ± 0.68 to 4.64 ± 0.52 cm (P < 0.01). Preoperatively, ejection phase indexes were normal or only marginally depressed in 12 of 16 patients but were moderately depressed in the remaining 4. At early follow-up (average 4 months) ventricular shortening tended to increase; and at late follow-up the fractional shortening of the minor axis, the ejection fraction and the mean velocity of circumferential fiber shortening increased to 0.39 ± 0.07, 0.68 ± 0.10 and 1.26 ± 0.22 circumference/sec, respectively, from preoperative values of 0.33 ± 0.09, 0.60 ± 0.14 and 1.05 ± 0.31 circumferences/sec (P < 0.05 for each index). In the four subjects with preoperative depression of left ventricular function, the extent and speed of myocardial shortening at late follow-up became normal in three subjects and remained moderately depressed in one patient. Paradoxical septal motion was observed immediately postoperatively and in the early follow-up studies, but it was noted in only 3 of 16 cases by the late follow-up period. Provided septal dyskinesia was not present, echocardiographic and first pass radionuclide determinations of ejection fraction correlated highly (r = 0.92). It is concluded that when aortic valve replacement for symptomatic aortic regurgitation is undertaken prior to severe myocardial decompensation, improvement in clinical status is associated with significant regression of myocardial hypertrophy, reduction in left ventricular size, evolution of a normal massvolume ratio, recovery of septal dyskinesia as revealed on echocardiography, and improvement in left ventricular function. These data do not define the type and degree of left ventricular dysfunction which is irreversible.
Hidden Disparities: How Courses and Curricula Shape Opportunities in Mathematics During High School

Efforts to promote academic achievement by increasing access to courses, especially in mathematics, may mask educational disparities if variations in curriculum are not also monitored. A multi-dimensional description of students’ mathematics curricula during high school was obtained from analyses of surveys, transcripts, and textbooks collected for a nationally representative study of adolescents during the mid-1990s. Few gaps in the number of years or credits in mathematics coursework were found. However, the quantity and cognitive challenge of instructional materials in textbooks adopted for those courses differed significantly both across and within mathematics tracks. Differences in the quality of curriculum accumulating during high school were also related to parents’ education level. Reducing such gaps in learning opportunities would require teachers to supplement adopted instructional materials to ensure that all students receive a high quality mathematics curriculum.