cssi/SciSciGPT-SciSciNet huggingface dataset:
5-Enolpyruvylshikimate-3-phosphate synthase from Escherichia coli—The substrate analogue bromopyruvate inactivates the enzyme by modifying Cys-408 and Lys-411

In order to identify the essential reactive amino acid residues of 5-enolpyruvylshikimate-3-phosphate synthase, the reaction of the enzyme with its substrate analogue bromopyruvate was investigated. Incubation of the enzyme with bromopyruvate resulted in a time-dependent loss of enzyme activity. The inactivation followed pseudo-first-order and saturation kinetics with a Kinact of 28 microM and a maximum rate constant of 0.31 min-1. The inactivation was prevented by preincubation of the enzyme with the substrates shikimate 3-phosphate, 5-enolpyruvylshikimate 3-phosphate or by the combination of shikimate 3-phosphate plus glyphosate (N-phosphonomethylglycine), an inhibitor of the enzyme. Addition of sodium [3H]borohydride to the reaction mixture had no effect on the rate of inactivation but resulted in the incorporation of 3H label to the modified enzyme. Upon 90% inactivation, approximately 1 mol of bromo[14C]pyruvate was incorporated per mole of enzyme modified in the absence or presence of sodium borohydride. When the enzyme was incubated with bromopyruvate in the presence of sodium [3H]borohydride, approximately 1 mol of 3H label was found to be associated per mole of the modified enzyme. Tryptic digestion of these labeled proteins followed by reverse phase chromatographic separation resulted in the isolation of three radioactive peptides. Analyses of these three peptides indicated that bromopyruvate inactivated the enzyme by modifying Cys-408 and Lys-411, which are conserved in all enzyme sequences studied to date.
Distinct regulation of interleukin‐17 in human T helper lymphocytes

Objective Interleukin-17 (IL-17)–producing T helper cells have been proposed to represent a separate lineage of CD4+ cells, designated Th17 cells, which are regulated by the transcription factor retinoic acid–related orphan receptor γt (RORγt). However, despite advances in understanding murine Th17 differentiation, a systematic assessment of factors that promote the differentiation of naive human T cells to Th17 cells has not been reported. The present study was undertaken to assess the effects on naive human CD4+ T cells of cytokines known to promote murine Th17 cells. Methods Human naive and memory CD4+ T cells isolated from peripheral blood were activated and cultured with various cytokines. Cytokine production was measured by enzyme-linked immunosorbent assay and flow cytometry. Messenger RNA was measured by quantitative polymerase chain reaction. Results In response to anti-CD3/anti-CD28 stimulation alone, human memory T cells rapidly produced IL-17, whereas naive T cells expressed low levels. Transforming growth factor β1 and IL-6 up-regulated RORγt expression but did not induce Th17 differentiation of naive CD4+ T cells. However, IL-23 up-regulated its own receptor and was an important inducer of IL-17 and IL-22. Conclusion The present data demonstrate the differential regulation of IL-17 and RORγt expression in human CD4+ T cells compared with murine cells. Optimal conditions for the development of IL-17–producing T cells from murine naive precursors are ineffective in human T cells. Conversely, IL-23 promoted the generation of human Th17 cells but was also a very potent inducer of other proinflammatory cytokines. These findings may have important implications in the pathogenesis of human autoimmunity as compared with mouse models.
Factors involved in herbivore food preference

Abstract Herbivore food preference can be measured either in terms of attractiveness or of edibility: these quantities are not necessarily correlated. The isopod Idotea baltica (Pallas) is attracted to large, tough, branched algae (perennials) while the amphipod Ampithoe valida (Smith) is attracted to softer, filamentous or bladed algae (ephemerals). Attractiveness for Ampithoe is related to the nutritive value of the algae; this is not so for Idotea , which responds more to algal morphology and availability. Idotea's mobility, possible susceptibility to fish predation, and preference for moderate wave exposures may select for a primary response to algae as habitat rather than as food source.
The need for two large schmidts

Abstract A 20-year sky survey in two colors is proposed that would photograph a volume of space about 20 times that reached by the National Geographic Society Palomar Sky Survey, and with three times the scale. Two f/3–75, 96-inch schmidts would be needed and would seem to be technically and financially feasible. The problems of plate size, lengthy exposure times, seeing criteria, program completion time and costs are discussed. Quite possibly the most significant discoveries resulting from such a survey would be of objects and would concern physical phenomena that we know nothing of today.
Couples' Concurrent Cognitions The Influence of Relational Satisfaction on the Thoughts Couples Have as They Converse

Studies of cognition in relationships show that people's thoughts about their partners shape and reflect the quality of relationships. Some research further suggests that women's cognitions are more relationship-centered than men's. The data supporting these arguments, however, often are based on partners' retrospective reports or responses to hypothetical scenarios. This study examined partners' concurrent cognitions—the thoughts they have during the course of interaction. Data were collected using a modification of “protocol analysis.” Partners conversed over networked computers and also voiced what they were thinking. Results indicated that those who were dissatisfied with their relationship expressed significantly more negative thoughts about their partner, fewer positive thoughts about their partner, and fewer positive thoughts about their relationship than did those who were satisfied. Dissatisfied men vocalized fewer negative thoughts about themselves than did those who were satisfied. ‘Women's thoughts were not more focused on relationship-oriented issues than were men's; men expressed more negative cognitions about relationships. The findings confirm that there are distinctions between the concurrent cognitions of satisfied and dissatisfied partners. Researchers should continue questioning the influence of gender on the ways partners evaluate their relationships.
Abnormal fMRI Connectivity in Children with Dyslexia During a Phoneme Task: Before But Not After Treatment

Abstract Brains of 18 children with dyslexia (5 girls, 13 boys) and 21 without dyslexia (8 girls, 13 boys) were scanned before and after the children with dyslexia received instructional treatment. Both at Time 1 and Time 2 all children performed an fMRI phoneme mapping task during brain scanning—deciding whether letter(s) in pair of pronounceable nonwords could stand for the same sound. Results were analyzed with a seed point correlational method for functional connectivity from four seed points based on prior studies: inferior frontal gyrus, middle frontal gyrus, the occipital region, and cerebellum. At Time 1 before treatment, a significant difference in fMRI connectivity occurred between children with dyslexia and normal reading controls in the left inferior frontal gyrus and its correlations with right and left middle frontal gyrus, right and left supplemental motor area, left precentral gyrus, and right superior frontal gyrus. There were no significant differences for the seed regions placed in the middle frontal gyrus, occipital gyrus or cerebellum. Children with dyslexia had greater functional connectivity from the left inferior frontal gyrus seed point to the right inferior frontal gyrus than did the children without dyslexia. Compared to adults with and without dyslexia who differed in bilateral connectivity from inferior frontal gyrus on the same task, the children with and without dyslexia differed in left side connectivity from left inferior frontal gyrus. At Time 2 after treatment, the children with dyslexia, who had participated in a 3-week instructional program that provided explicit instruction in linguistic awareness, alphabetic principle (taught in a way to maximize temporal contiguity of grapheme–phoneme associations), decoding and spelling, and a writers’ workshop, did not differ from the children without dyslexia in any of the clusters in the group difference map identifying differences between dyslexics and good readers, showing that functional connectivity (and not just regions of interest) may normalize following instructional treatment.
Performance comparisons of multi-modal medical image registration algorithms

In this paper we study the performance of the maximization of mutual information (MMI) based registration algorithm using a select number of medical image data sets. Where appropriate, we present a comparison of the MMI based algorithm with surface based and centerline (medial axes) based registration algorithms. In the paper we first show that the MMI based registration algorithm can accurately estimate the registration parameters using real patient image data sets. We then present a data set where the MMI based estimates are not as accurate. For this image data set, the MMI based algorithm requires sufficiently close initialization to the true parameters. Also, we show that for such image data sets feature based algorithms, such as, surface based and the centerline based methods, can accurately estimate the registration parameters. The paper also discusses the effects of the optimization method (Powell's versus Simplex) on the quality and computation time of the MMI based and correlation based registration algorithms.
Membrane Compartmentation Is Required for Efficient T Cell Activation

The plasma membrane of mammalian cells contains detergent-resistant membrane rafts enriched in glycosphingolipids and cholesterol. Although several important signaling molecules have been found in such rafts, evidence documenting a functional role for their localization has been scarce. Using a fractionation scheme that preserves tyrosine phosphorylation, we show that T cell activation leads to a striking compartmentation in the rafts of activated T cell receptor and associated signal-transducing molecules. Conditions that reversibly disrupt raft structure either by dispersing their contents or by forcing their internalization reversibly disrupt the earliest steps of T cell activation. Thus, raft integrity is a prerequisite for efficient T cell receptor signal transduction.
The Impact of Uncertainty on Decision Making in Prenatal Consultations: Obstetricians' and Midwives' Perspectives

This article examines decision making in prenatal consultations, how obstetricians (OBs) and midwives differ, and the role of uncertainty in these processes. Using participant-observation, comparative case-study methodology, pregnant women were observed and audio-recorded in their pre- and postnatal appointments, and in-depth, semistructured interviews were conducted with mothers and providers. Although decision-making processes appear similar between the OBs and midwives, closer analysis, employing problematic integration theory, reveals marked differences in providers' probabilistic and evaluative orientations that carry clear implications for both mothers and providers during pregnancy care.
A topology-independent transmission scheduling in multihop packet radio networks

In this paper, based on coding theory concepts, a new time scheduling algorithm for multihop packet radio networks is described. Each mobile host is assigned a word from an appropriate constant weight code of length n, distance d and weight w. The host can send a message at the j/sup th/ slot provided the assigned code has a 1 in this j/sup th/ bit. The proposed algorithm is better than the previously known algorithms in terms of minimum system throughput. The algorithm also preserves other desired properties, such as topology independence, guaranteed minimum throughput, bounded maximum delay, and fair transmission policy.
New Directions in Research on Public Health and Health Literacy

Numerous calls for a public health approach to health literacy and visions of a health literate society have appeared in recent years. Yet, many gaps in what we know about and do to improve health literacy remain. Major developments at the national level in the last decade help define the role of health literacy in creating better public health and have set the stage for new investigations in public health and health literacy. Four frameworks are examined for their usefulness in posing new questions about public health and health literacy: Healthy People, the Ten Essential Public Health Functions, health promotion, and health disparities. Each of the frameworks generates questions and uses methods that can produce new findings about health literacy. Using the frameworks will open new investigations into population health and health literacy improvement at multiple levels.
Interference effects of Stroop color-word test in childhood, adulthood, and aging.

(1962). Interference Effects of Stroop Color-Word Test in Childhood, Adulthood, and Aging. The Journal of Genetic Psychology: Vol. 100, No. 1, pp. 47-53.
Multi-user TCP throughput in multi-rate cellular networks

In this paper, we consider a multi-rate cellular system like High Data Rate (HDR) and represent the state space using a Markov chain. We compute the transition probability of each state assuming that transition is possible between adjacent states. We focus on the TCP performance with a radio link protocol implemented that tries to hide channel related losses from TCR We use an M/G/l queuing model to capture the delay and throughput for different schedulers. We also illustrate how TCP throughput, link layer throughput, delay, and fairness are affected and dependent on parameters like number of users in the system and the underlying radio link protocol.
Can a Complete Fetal Echocardiogram Be Performed at 12 to 16 Weeks' Gestation?

Background The aim of this study was to determine the feasibility of performing complete early fetal echocardiography (FE) at Methods Fetal echocardiograms obtained in pregnancies studied at Results One hundred thirty-nine pregnancies were assessed by early FE at 17 weeks) FE. Of these, complete fetal echocardiograms were obtained in 27 early (24%; 95% confidence interval [CI], 17%–33%) and 76 later (67%; 95% CI, 58%–75%) exams. In most early exams, color and pulsed Doppler interrogation of the pulmonary veins was unsuccessful. If pulmonary vein Doppler assessment was excluded, complete studies were performed in 80 early exams (71%; 95% CI, 62%–78%) and 97 standard midtrimester exams (86%; 95% CI, 78%–91%). On early FE, heart disease was suspected in 20 pregnancies, and although no major congenital heart disease was missed, in four pregnancies, ventricular septal defects were found only on later FE or after birth. Conclusions Early FE yields nearly complete information (exclusive of pulmonary venous interrogation) in the majority of patients.
The accuracy of the pseudopotential approximation within density-functional theory

We have investigated the accuracy of pseudopotential (PSP) density-functional calculations with respect to the corresponding all-electron (AE) results for a variety of atoms and small molecules. It is found that most of the deviations between ab-initio PSP and AE calculations are due to the linearization of the exchange-correlation functional within the PSP approach. This problem can be eliminated by applying nonlinear core corrections (NLCC). We find that a correct description of spin-polarized states requires the NLCC, even for first-row atoms. This is essential for simulations of magnetic systems and reaction processes which involve radicals. The NLCC is also essential for a realistic description of elements with more long-range core states such as alkali atoms. A further improvement of pseudopotential accuracy may be achieved by explicitly including semi-core states in the calculation.
Interleukin-6 genetic variability and adiposity: associations in two prospective cohorts and systematic review in 26,944 individuals.

Context: IL-6 (IL6) is an immune-modulating cytokine associated with obesity in humans. Objective: Our objective was to assess the associations between the genetic variability of IL6 gene and adiposity and long-term changes. Design and Subjects: We determined the linkage disequilibrium-tagging single-nucleotide polymorphisms of IL6 gene in 2255 healthy women and 980 healthy men from two prospective cohorts. We also conducted a metaanalysis on the associations between polymorphism −174G>C (rs1800795) and adiposity. Results: IL6 haplotype 222211 (possessing rs2069827, rs1800797, rs1800795, rs1554606, rs2069861, and rs1818879; 1 codes the common and 2 codes the minor alleles) was consistently and significantly associated with greater waist circumference (P = 0.009 in men; P = 0.0003 in women) and baseline body mass index (BMI) (P = 0.01 in men; P = 0.046 in women) compared with the most common haplotype 111112. Haplotype 222211 was also associated with significantly higher early-adulthood BMI in women (P = 0...
Characterize and Quantify Residual Steelhead in the Clearwater River, Idaho, 2002 Annual Report.

We tagged 4,513 hatchery steelhead from Dworshak National Fish Hatchery (NFH), with Passive Integrated Transponder (PIT) tags to evaluate factors contributing to residualism. Steelhead from typical growth ponds (System I) averaged eight mm less and traveled two days faster to Lower Granite Dam than those in faster growth ponds (System II). The mean detection rates of steelhead by rearing system were 57.4%, 55.9%, and 57.8% for System I, System II, and System III. Steelhead released into Clear Creek, South Fork Clearwater River and directly from Dworshak NFH had detection rates of 55.0%, 59.1%, and 57.8%, respectively. Overall detection rate for all release sites, rearing systems and egg takes was 54.1%. We PIT tagged an additional 270 hatchery steelhead in the North Fork and mainstem Clearwater rivers and the adult ladder at Dworshak National Fish Hatchery between May 15 and October 29. In the four tributaries sampled, no hatchery steelhead were captured or observed. A total of 51 code d-wire tags were recovered; 3 were released at Dworshak NFH in 2001 and 47 in 2002. One fish was released at Clear Creek. Although sample sizes were small, we were able to verify that at least 33 residual steelhead tagged in 2001more » persisted in the Clearwater River during winter and were detected at downstream dams in 2002. Final analysis will include influences of water flow and temperature in emigration success.« less
Exact partition function and boundary state of 2D massive Ising field theory with boundary magnetic field

Abstract We compute the exact partition function, the universal ground-state degeneracy and boundary state of the 2D Ising model with boundary magnetic field at off-critical temperatures. The model has a domain that exhibits states localized near the boundaries. We study this domain of boundary bound state and derive exact expressions for the “ g function” and boundary state for all temperatures and boundary magnetic fields. In the massless limit we recover the boundary renormalization group flow between the conformally invariant free and fixed boundary conditions.
Valence bond isomers of aromatic systems

The prefix xn is proposed for the classification of valence-bond isomers of aromatic systems, where n is the change in the number of rings or in the number of π-bonds on isomerization. Representatives of the x1-series are Dewar benzene and 9, 10-dihydronaphthalene. Benzvalene and prismane belong to the x2 and x3 series, respectively. Various derivatives of such valence-bond isomers have recently become known.
Punctate epiphyses associated with Turner syndrome

The radiographic observation of stippled calcification in cartilage defines the chondrodysplasia punctata group of bone dysplasias. Several other diseases may be associated with the radiographic finding of punctate epiphyses, usually uncommonly – for example, trisomy 21. Other more subtle chromosomal abnormalities also associated with punctate epiphyses include microdeletions of the X chromosome. A case of Turner syndrome with punctate calcification of the epiphyses is described.
Tendon arrangement and muscle force requirements for human-like force capabilities in a robotic finger

Human motion can provide a rich source of examples for use in robot grasping and manipulation. Adapting human examples to a robot manipulator is a difficult problem, however, in part due to differences between human and robot hands. Even hands that are anthropomorphic in external design may differ dramatically from the human hand in ability to grasp and manipulate objects due to internal design differences. For example, force transmission mechanisms in robot fingers are generally symmetric about flexion/extension axes, but in human fingers they are focused toward flexion. This paper describes how a tendon driven robot finger can be optimized for force transmission capability equivalent to the human index finger. We show that two distinct tendon arrangements that are similar to those that have been used in robot hands can achieve the same range of forces as the human finger with minimal additional cost in total muscle force requirements.
Child Abuse as an Area of Aggression Research

Child abuse research and research on aggression have not been well integrated. This paper reviews current parallel research on aggressive behavior and child abuse and concludes that the 2 areas have much in common; a rapprochement might be especially fruitful. Special attention was given to problems in definition, the role of aggressive repertoires, target characteristics, and aggressive traits as factors in research on abuse of offspring.
Predator–prey interactions between crayfish (Orconectes juvenilis) and snails (Physa gyrina) are affected by spatial scale and chemical cues

. We conducted two experiments to compare the behaviors of predatory crayfish (Orconectes juvenilis) and snail prey (Physa gyrina), with and without exposure to injured-snail cues, in seven different sizes of arena. Individuals in both O. juvenilis and P. gyrina are known to obtain information about predation events from chemical cues present in the water, but the effect of spatial scale on this information or the ensuing interaction has not been previously investigated. We found that crayfish were generally more active in larger arenas, but their response to injured-snail cues decreased as arena size increased. Snails responded to injured-snail cue by seeking refuge, but responded less strongly in larger arenas. Less time was required for crayfish to capture a snail in the presence of injured-snail cue, and there was an interaction between cue and arena size evident in middle-sized arenas. Consumption time was lower in the presence of injured-snail cue but was unaffected by arena size. Based on these results, we conclude that the effects of injured-snail cue are mediated by spatial scale, and this affects the outcome of this predator–prey interaction. Spatial scale should be considered in the design and interpretation of other predator–prey studies, particularly when sensory or motility differences exist between predators and prey that affect how each gathers information about the environment.
Chronic Partial Occlusion of the Pulmonary Artery in Cats Change In Ventricular Action Potential Configuration During Early Hypertrophy

The relation of single cell electrical activity to generation of force was determined for myocardium during the development of hypertrophy induced by pressure loading. Transmembrane potentials and isometric active force at optimal length (P o ) were monitored in isolated right ventricular papillary muscles and trabeculae carneae after inducing chronic right ventricular outflow tract obstruction. Cats subjected to partial pulmonary artery occlusion or to sham operation were studied 1, 3, 7, 10, 21, and > 90 days after surgery. Right ventricular muscles were stimulated at 30/min at optimal length in Tyrode9s solution (36°C). Muscles from sham-operated and 1 day pressure-loaded hearts had electrical and mechanical properties similar to normal muscles. Right ventricular peak systolic and end-diastolic pressures were increased for 1 and 3 day pressure-loaded hearts; the percent of right ventricular water was increased for 3, 7, and 10 day pressure-loaded hearts. Muscles from 3 day pressure-loaded ventricles had significantly decreased P o , maximum rate of force development, time to peak force, and duration of contraction compared with normal muscles, and their action potential plateaus originated at more negative potentials (mean 24.7 mv for 11 muscles). The alteration in action potential configuration was less obvious in muscles studied 7 and 10 days after partial pulmonary artery occlusion and did not occur 21 and > 90 days after pressure loading; however, P o and maximum rate of force development remained decreased, although time to peak force and duration of contraction returned to normal for preparations from 7, 10, 21, and > 90 day pressure-loaded ventricles.
Equilibrium Heat Distribution

In the next chapter, we will see the Ascoli-Arzela and Schauder theories used once again, to demonstrate the existence of solutions to a type of problem in the theory of ordinary differential equations that is quite different from what we encountered in studying the forced pendulum. The purpose of the present chapter is to present an illustration of how problems like those discussed in the next chapter come up. Although a single application is hardly sufficient to justify the entire theoretical apparatus, I hope that you will be willing to take my word for it that there are more where this one came from. Furthermore, by following the steps from the mathematical model of the physical problem to the abstract mathematics, you will be able to see why the differential equation problem has the particular form that it does. If I didn’t show you something of the sort, you would have every right to suspect that the somewhat complicated hypotheses of the mathematical problem were constructed just so that the abstract theory we’ve been developing could be applied to it.
Human serum catalase decreases endothelial cell injury from hydrogen peroxide

Serum from normal human subjects contained variable amounts of catalase activity, which was inhibitable by heat, azide, trichloroacetic acid (TCA), or aminotriazole treatment. Serum also decreased hydrogen peroxide (H2O2) concentrations in vitro and H2O2-mediated injury to cultured endothelial cells. By comparison, heat-, azide-, TCA-, or aminotriazole-treated serum neither decreased H2O2 concentrations in vitro nor reduced H2O2-mediated damage to endothelial cells. We conclude that serum catalase activity can alter H2O2-dependent reactions. We speculate that variations in serum catalase activity may alter individual susceptibility to oxidant-mediated vascular disease or be a factor when added to test systems in vitro.
Planning an Athletic Field

(1930). Planning an Athletic Field. The Journal of Health and Physical Education: Vol. 1, No. 9, pp. 38-42.
Design and implementation of a scalable membership service for supercomputer resiliency-aware runtime

As HPC systems and applications get bigger and more complex, we are approaching an era in which resiliency and run-time elasticity concerns become paramount. We offer a building block for an alternative resiliency approach in which computations will be able to make progress while components fail, in addition to enabling a dynamic set of nodes throughout a computation lifetime. The core of our solution is a hierarchical scalable membership service providing eventual consistency semantics. An attribute replication service is used for hierarchy organization, and is exposed to external applications. Our solution is based on P2P technologies and provides resiliency and elastic runtime support at ultra large scales. Resulting middleware is general purpose while exploiting HPC platform unique features and architecture. We have implemented and tested this system on BlueGene/P with Linux, and using worst-case analysis, evaluated the service scalability as effective for up to 1M nodes.
Should Motivational Humeans be Humeans About Rationality

For many years, the received view was that the Humean Theory of Motivation. concisely captured in the slogan that reason alone cannot motivate actions, is inconsistent with any very robust non-instrumental theory of rationality. This in turn meant that the Humean Theory was also incompatible with robust versions of moral rationalism." Recently various authors have advocated positions which challenge the prevailing orthodoxy in various ways. Michael Smith, for example, advocates both the Humean Theory of Motivation and an Anti-Humean theory of rationality.' And Christine Korsgaard, herself a rationalist, in at least one paper has seemed to argue that robust rationalism about moral judgements is compatible with Bernard Williams, Humean motivational assumptions in his well-known paper, "Internal and External Reasons." The trick, she suggests, is to think of rationality as requiring a certain sort of disposition, broadly classifiable as a desire whose content is such that rational individuals will always possess the desire that the Humean Theory requires for motivation." In this paper I will argue that the orthodox view has a lot going for it. Its strength can be easy to miss if we focus on idealized, fully rational and fully informed agents. The availability of information or the lack thereof can influence what we have reason to do, and I will argue that certain versions of rationalism have trouble taking account of this if they also want to remain consistent with a Humean theory of motivation. Furthermore, such rationalists often are not able to say what they should want to say about the reasons had by those who are somewhat irrational. My exposition will be somewhat dialectical. I begin by sketching some of the motivations for the orthodox position resting on motivational internalism about reasons for action. I will then outline a tempting strategy for making the Humean Theory of Motivation compatible with an anti-Humean theory of rationality. Mark van Roojen
Optimal Power Descent Guidance with 6-DoF Line of Sight Constraints via Unit Dual Quaternions

In this paper, we present a model predictive control (MPC) approach for powered descent guidance and control synthesis in the presence of line of sight and glide slope constraints. The design of an autonomous control algorithm for such a mission scenario is challenging due to fact that the constraints are coupled with rotational and translational motions of a lander spacecraft, leading to a complex configuration space. We approach this problem by representing the general dynamics of the rigid body in an uniform gravity field as a piece-wise affine system utilizing the unit dual quaternion parameterization. Such a parameterization enables a 6-DOF motion prediction algorithm while also allowing selecting a quadratic cost on the required acceleration commands in order to minimize propellant consumption. The constraints are imposed to ensure that the lander’s position and orientation are not violating the constraints. A novel feature of this approach is the development of convex representable subset of unit dual quaternions that correspond to translational and rotational states satisfying predefined types of constraints with respect to a moving body frame. The stability and feasibility issues of the piece-wise affine MPC approach are also discussed. Simulation results are then presented to demonstrate the effectiveness of the proposed algorithm for powered descent guidance.
In search of sacred time. Jacobus de Voragine and the Golden Legend

Jacques Le Goff’s interest in the medieval concept of time goes back at least to 1960, when he wrote his seminal article on ‘Temps de l’Eglise et temps du Marchant’ (Annales 15, 1960). In what was ...
Selective Epitaxy of Compound Semiconductors in MOVPE Growth: Growth, Modelling, and Applications

Selective cpitaxial growth during metal-organic vapor phase epitaxy (MOVPE) can be accomplished over a wide range of growth conditions through the usC of alternative growth precursors. We have used chlorine-containing growth precursors, such as diethyl gallium chloride, (C2H5)2GaCl, to selectively grow GaAs and AIGaj As. The growth process has been thermodynamically modelled in order to estimate relative growth rates and alloy composition. This model indicates that near the growth front the growth process is chemically similar to the inorganic-based growth of compound semiconductors. This growth technique has been applied to the growth of extremely low resistance ohmic contact structures and quantum well structures.
Microfluidics made easy: A robust low-cost constant pressure flow controller for engineers and cell biologists

Over the last decade, microfluidics has become increasingly popular in biology and bioengineering. While lab-on-a-chip fabrication costs have continued to decrease, the hardware required for delivering controllable fluid flows to the microfluidic devices themselves remains expensive and often cost prohibitive for researchers interested in starting a microfluidics project. Typically, microfluidic experiments require precise and tunable flow rates from a system that is simple to operate. While many labs use commercial platforms or syringe pumps, these solutions can cost thousands of dollars and can be cost prohibitive. Here, we present an inexpensive and easy-to-use constant pressure system for delivering flows to microfluidic devices. The controller costs less than half the price of a single syringe pump but can independently switch and deliver fluid through up to four separate fluidic inlets at known flow rates with significantly faster fluid response times. It is constructed of readily available pressure regulators, gauges, plastic connectors and adapters, and tubing. Flow rate is easily predicted and calibrated using hydraulic circuit analysis and capillary tubing resistors. Finally, we demonstrate the capabilities of the flow system by performing well-known microfluidic experiments for chemical gradient generation and emulsion droplet production.
Ensemble Reduction via Logic Minimization

An ensemble of machine learning classifiers usually improves generalization performance and is useful for many applications. However, the extra memory storage and computational cost incurred from the combined models often limits their potential applications. In this article, we propose a new ensemble reduction method called CANOPY that significantly reduces memory storage and computations. CANOPY uses a technique from logic minimization for digital circuits to select and combine particular classification models from an initial pool in the form of a Boolean function, through which the reduced ensemble performs classification. Experiments on 20 UCI datasets demonstrate that CANOPY either outperforms or is very competitive with the initial ensemble and one state-of-the-art ensemble reduction method in terms of generalization error, and is superior to all existing reduction methods surveyed for identifying the smallest numbers of models in the reduced ensembles.
Evaluation of obesity. Who are the obese

Obesity has become increasingly prevalent in westernized countries, and in the United States it has reached epidemic proportions. The risks linked to obesity--such as cardiovascular disease, hypertension, and type 2 diabetes--make this condition one that deserves time and recognition by primary care physicians. Here, Dr Bray reviews the characteristics that define overweight and obesity, the factors that contribute to the pathogenesis of obesity, and current approaches to its management.
Information empowers vegetable supply chain

This study is about how information systems may benefit vegetable supply chain.We studied information needs and sharing among vegetable farmers and vendors.The farmers and vendors had different information needs and sharing strategies.The findings justify building a center of agricultural information in the area.Cross-discipline research like this should help cope with agricultural challenges. Agricultural extension systems often fail due to inadequate knowledge of farmers' information needs and sharing strategies. This study aims to meet an urgent need of studying information needs and sharing strategies among vegetable farmers and vendors in Chengdu, China, whose results might be used in building a center of agricultural information disseminating vegetable production and marketing information. The findings disclose interesting differences between the farmers and vendors regarding their willingness to join such a center, information needs, sharing strategies and preferred information sources. Ample evidences justify the construction of the proposed center of agricultural information, which should not only empower the vegetable farmers and vendors but also enhance the efficiency of the existing vegetable supply chain and food security. Cross-discipline research involving both agriculture and communication scholars, like this, should shed more insights on working out strategies to cope with agricultural challenges.
Navigating the Local Modes of Big Data: The Case of Topic Models

We consider the problem of multi-modality as it arises in the use of latent variable models to analyze big data. We focus in particular on unsupervised topic models which provide a powerful method for discovering latent structure in large corpora of unstructured texts. Although these approaches have proven useful throughout the social sciences, these models often have extremely multi-modal likelihood surfaces and different starting values will produce different parameter estimates. In this chapter, we develop tools for assessing sensitivity to initialization, selecting a model to analyze and improving the quality of starting values. We offer the perspective that even if the user is unable to identify the global maximum, local modes can provide useful and sometimes even better solutions for the data under study. ∗Prepared for “Data Science for Politics, Policy and Government”, R. Michael Alvarez, editor. The research assistance of Antonio Coppola, under the support of the Harvard BLISS program, was extremely valuable for this paper. Our thanks to participants of the Harris School Political Economy workshop and Princeton University Political Methodology workshop for reinforcing the need to write this chapter, and Jetson Leder-Luis for comments. An R package for estimating the Structural Topic Model is freely available at www.structuraltopicmodel.com.
Analyses of Indoor Optical Wireless Channels Based on Channel Impulse Responses

This chapter analyzes different indoor channel impulse responses and their Fourier transforms, and the frequency responses of the channels. It shows that the size of the room and the positions of transmitters and receivers have a big influence on their achievable performance. The chapter shows that line‐of‐sight (LOS) channels have better ‐3 dB bandwidth and smaller root‐mean‐square (rms) delay spread compared to NLOS channels. It explains the effects of adding furniture in a room. The conclusion is that if the receiver location is not near some furniture which is at a higher height than the receiver itself, the results obtained from analyzing an empty room can be used interchangeably without introducing too many significant errors. Lastly, signal‐to‐noise ratio (SNR) calculations are used to show that using a bare photodiode, even an avalanche photodiode (APD), will not be good enough to obtain sufficient SNR to ensure a bit‐error‐rate (BER) of 10‐6.
Development of Oligodendrocytes in the Vertebrate CNS

One characteristic of the vertebrate CNS is the presence of myelin, a fatty insulation that surrounds individual axons and facilitates the rapid conduction and enhances the efficiency of electrical impulses along the length of the axon. Oligodendrocytes are the primary cellular source of myelin in the CNS, and their development has been extensively studied over the last 2 decades. Compact myelin appears as concentric rings of modified plasma membrane that ensheaths a segment or internode along an axon. The gap between two adjacent internodes on the same axon is known as the Node of Ranvier and is a complex structure that maintains the integrity of the axon–glial unit. The discontinuous nature of myelin and the localized concentration of ion channels at Nodes of Ranvier result in accelerated conduction of electrical signals along axons and a lowering of the threshold for propagating such signals. Not all axons are myelinated, and some axons have regions that are both unmyelinated and myelinated. The functioning of the adult nervous system is however dependent on the appropriate level of myelination, and diseases or injuries that reduce the extent of local myelination result in functional deficits.
Interface passivation by deuterium for nanoscale CMOS devices

Passivation of interfaces such as Si/SiO/sub 2/ and Si/HfO/sub 2/ (Si/high-k) by deuterium instead of hydrogen is getting significant attention for scaled CMOS devices. This paper introduces the various methods of deuterium incorporation at the interface including thermal annealing and deuterium implantation at the Si/SiO/sub 2/ interface when a thin oxide is grown on implanted silicon substrate. In case of annealing thermal budget is a limiting factor whereas for implantation, energy and implantation dose significantly influence the interface passivation. Interface passivation by hydrogen and deuterium implantation is discussed. Observed interface states at the Si/SiO/sub 2/ interface suggests an isotope effect where deuterium implanted devices yielded better interface results compared to that of hydrogen implanted devices. Transient enhanced diffusion of implanted hydrogen and deuterium is affected by the implantation damage.
Learning the Fundamentals of Kinetics and Reaction Engineering With the Catalytic Oxidation of Methane

Understanding catalytic chemistry, collecting and interpreting kinetic data, and operating chemical reactors are critical skills for chemical engineers. This laboratory experiment provides students with a hands-on supplement to a course in chemical kinetics and reaction engineering. The oxidation of methane with a palladium catalyst supported on alumina (Pd/Al2O3) is used to introduce the ideal batch, plug-flow, and continuous stirredtank reactor types. Students can vary reactant partial pressures, temperature, and catalyst particle size to measure apparent activation energies, apparent reaction orders, effects of diffusion and mass transfer within catalytic pellets, and effects of product inhibition on reaction kinetics.
Feeding Behavior and Diet in Paranthropus boisei : The Limits of Functional Inference from the Mandible

The craniofacial morphology of Paranthropus boisei is highly derived, representing the evolutionary culmination of one robust australopith lineage. Following its discovery, OH 5 was popularly described as “Nutcracker Man,” and this image of the East African robust australopiths as hard-object feeders has persisted for the last half-century. Emerging lines of evidence, however, suggest that the diet of this species was not primarily comprised of hard foods. An alternative view is that P. boisei consumed a relatively tough diet of grasses and sedges. As the covariation of diet and/or feeding behavior with mandibular morphology has been the focus of a voluminous literature, this paper evaluates whether the jaws of P. boisei – interpreted within a framework of masticatory mechanics in particular and bone biology in general – can be interpreted as functionally coherent with a herbivorous diet that lacked a significant component of durophagy. In terms of proportion and geometry, australopith mandibles have no parallel among living primates and P. boisei represents the extreme expression of this morphotype. From the perspective of primate masticatory biomechanics, the inference of loading regimes experienced in this fossil species is speculative, and subsequent inference of diet from corpus geometry should be regarded with skepticism. However, in terms of overall mandibular architecture, and from what is known about the biomechanical influences governing bone hypertrophy, competing hypotheses of dietary specialization are equally plausible on morphological criteria. Mandibular hypertrophy is an expected outcome of a fibrous diet requiring extensive and prolonged mastication, especially in a taxon in which occlusal morphology is suboptimal for the breakdown of fibrous foods.
Stepwise regression modeling for compressive strength of alkali-activated concrete

Abstract This paper presents the results from a parametric experimental investigation of the compressive strength of alkali-activated concrete. The effects of curing condition (moist-cured versus heat-cured), sodium oxide dosage, silica dosage, silica modulus (relative dosage of silica to sodium), solution/binder ratio, and free water/binder ratio on the compressive strength of sodium silicate-activated fly ash and slag cement concrete are evaluated. More than 5000 specimens with 676 unique combinations of mixture proportion and curing condition were tested. The marginalized effects of each parameter indicate effects similar to those identified by previous studies. Predictive models for the compressive strength of fly ash and slag cement-based concretes are developed by stepwise regression analysis. Although the specific models presented in this paper are applicable only for the materials and activators identified herein, the modeling procedures are generalized results are of doubtless utility for the design of alkali-activated concrete mixtures.
New astrophysical bounds on ultralight axionlike particles

Motivated by tension between the predictions of ordinary cold dark matter (CDM) and observations at galactic scales, ultralight axionlike particles (ULALPs) with mass of the order ${10}^{\ensuremath{-}22}\text{ }\text{ }\mathrm{eV}$ have been proposed as an alternative CDM candidate. We consider cold and collisionless ULALPs produced in the early Universe by the vacuum realignment mechanism and constituting most of CDM. The ULALP fluid is commonly described by classical field equations. However, we show that, like QCD axions, the ULALPs thermalize by gravitational self-interactions and form a Bose-Einstein condensate, a quantum phenomenon. ULALPs, like QCD axions, explain the observational evidence for caustic rings of dark matter because they thermalize and go to the lowest energy state available to them. This is one of rigid rotation on the turnaround sphere. By studying the heating effect of infalling ULALPs on galactic disk stars and the thickness of the nearby caustic ring as observed from a triangular feature in the infrared astronomical satellite map of our galactic disk, we obtain lower-mass bounds on the ULALP mass of order ${10}^{\ensuremath{-}23}$ and ${10}^{\ensuremath{-}20}\text{ }\text{ }\mathrm{eV}$, respectively.