cssi/SciSciGPT-SciSciNet huggingface dataset:
Some genetic aspects of the epilepsies: Waking and sleep EEGs in siblings of patients with various idiopathic and symptomatic seizure types

Waking and sleep EEGs were recorded in siblings of patients with various idiopathic and symptomatic seizure types. More than one-third of the siblings of nearly all seizure types showed epileptic activity (EA). The lowest rate of EA was found in siblings of patients with complex partial seizures (24.1%), the highest in those of patients with idiopathic absences (72%). More EA was found in siblings of patients with idiopathic absences (72%) than in those of patients with symptomatic absences (46.7%). On the other hand, the siblings of patients with idiopathic generalized tonic-clonic seizures (42%) showed the same rate of EA as those of patients with symptomatic tonic-clonic seizures (41%). By counting the EA, however, considerably more EA was found in siblings of patients with the idiopathic type (one paroxysm every 53 s) than in those of patients with the symptomatic type (one paroxysm every 229.3 s). One-quarter to one-half of the EA was recorded exclusively in sleep. Predominantly generalized spike-and-wave complexes were seen in siblings of all seizure types. Benign sharp wave foci were recorded in 1.5–5.8% of siblings of patients of nearly all seizure types, most frequently (5.8%) in those of patients with rolandic epilepsy. Photosensitivity was also found in siblings of patients of nearly all seizure types, most often in those of patients with absences (22.5%). The highest rates of EA were recorded in siblings of patients of all seizure types in the waking EEG during hyperventilation, during sleep in Stage C. The most EA was seen in siblings of nearly all seizure types in the age range between 6 and 15 years. Significantly more EA was recorded in siblings of female patients with Lennox-Gastaut syndrome (66.7%:33.3%), in those of patients with febrile seizures (68.5%:43.3%), as well as complex partial seizures (55.6%:20%). More EA was also seen in female siblings of patients with symptomatic generalized tonic-clonic seizures (54.5%:30%) and complex partial seizures (27.8%: 18.2%). A multifactorial mode of inheritance is supposed.
Mechanism of proton gating of a urea channel

The size and complexity of many pH-gated channels have frustrated the development of specific structural models. The small acid-activated six-membrane segment urea channel of Helicobacter hepaticus (HhUreI), homologous to the essential UreI of the gastric pathogen Helicobacter pylori, enables identification of all the periplasmic sites of proton gating by site-directed mutagenesis. Exposure to external acidity enhances [(14)C]urea uptake by Xenopus oocytes expressing HhUreI, with half-maximal activity (pH(0.5)) at pH 6.8. A downward shift of pH(0.5) in single site mutants identified four of six protonatable periplasmic residues (His-50 at the boundary of the second transmembrane segment TM2, Glu-56 in the first periplasmic loop, Asp-59 at the boundary of TM3, and His-170 at the boundary of TM6) that affect proton gating. Asp-59 was the only site at which a protonatable residue appeared to be essential for pH gating. Mutation of Glu-110 or Glu-114 in PL2 did not affect the pH(0.5) of gating. A chimera, where the entire periplasmic domain of HhUreI was fused to the membrane domain of Streptococcus salivarius UreI (SsUreI), retained the pH-independent properties of SsUreI. Hence, proton gating of HhUreI likely depends upon the formation of hydrogen bonds by periplasmic residues that in turn produce conformational changes of the transmembrane domain. Further studies on HhUreI may facilitate understanding of other physiologically important pH-responsive channels.
New moves of the spintronics tango

The ability of spintronics to re-energize itself in directions that germinate new subfields has made it one of the most fertile grounds for basic research aimed at future applications. A brief overview of the connections between five emerging subfields suggests exciting things to come.
SU-E-J-120: Reduction in Breathing Motion Intra-Fraction Variability through Prone Body Positioning

Purpose: Simplicity in treatment is preferable, whenever possible: it reduces errors, execution time and effort, and increases patient confidence. We aim at this benefit by using a natural body compression approach through positioning the patient prone, instead of the habitual (albeit unsubstantiated) supine positioning. The innovative premise tested in this work is that prone positioning can moderate the respiratory‐induced motion and make it more consistent from cycle‐to‐cycle, compared to supine positioning. Methods: Breathing traces from 8 patients positioned supine, then prone, were used to evaluate cycle‐to‐cycle variances in end‐of‐exhale(EoE), end‐of‐inhale(EoI) and average(AVE) locations, and to quantify the statistical significance at a p‐value=0.05. Population variances were also evaluated for these locations. Results: Prone positioning has improved EoE‐location consistency for all patients, and was superior in all but one case for AVE‐location. EoI reproducibility was poorer (improved in 5 out of 8 cases). Data analysis for the entire population reveals an overall improvement through prone positioning for all locations of interest. Variance reduction implies a corresponding reduction in the random component of the respiratory motion. Conclusions: Our analysis demonstrates statistically significant improvements in breathing pattern consistency in prone position. This conclusion can be extended to the tumor motion as well, under the assumption that the RPM traces and the tumor trajectories exhibit similar motion pattern characteristics, a condition often fulfilled. Radiotherapy with prone body positioning is straightforward and non‐invasive, and can be implemented without using complex respirationcontrol technology (therefore could become widespread available). The reduction in breathing variability through prone positioning offers the potential for 4DCT image acquisition with even fewer motion artifacts and for radiation delivery under anatomical conditions resembling more closely those from the pre‐treatment CT scans, while enabling the possibility of tumordose escalation at similar or reduced normal tissuedoses compared to the conventional supine treatment position.
Influence of norepinephrine on somatosensory neuronal responses in the rat thalamus: A combined modeling and in vivo multi-channel, multi-neuron recording study

Norepinephrine released within primary sensory circuits from locus coeruleus afferent fibers can produce a spectrum of modulatory actions on spontaneous or sensory-evoked activity of individual neurons. Within the ventral posterior medial thalamus, membrane currents modulated by norepinephrine have been identified. However, the relationship between the cellular effects of norepinephrine and the impact of norepinephrine release on populations of neurons encoding sensory signals is still open to question. To address this lacuna in understanding the net impact of the noradrenergic system on sensory signal processing, a computational model of the rat trigeminal somatosensory thalamus was generated. The effects of independent manipulation of different cellular actions of norepinephrine on simulated afferent input to the computational model were then examined. The results of these simulations aided in the design of in vivo neural ensemble recording experiments where sensory-driven responses of thalamic neurons were measured before and during locus coeruleus activation in waking animals. Together the simulated and experimental results reveal several key insights regarding the regulation of neural network operation by norepinephrine including: 1) cell-specific modulatory actions of norepinephrine, 2) mechanisms of norepinephrine action that can improve the tuning of the network and increase the signal-to-noise ratio of cellular responses in order to enhance network representation of salient stimulus features and 3) identification of the dynamic range of thalamic neuron function through which norepinephrine operates.
Measuring corrosion thinning by thermal-wave imaging

We describe an IR thermal wave imaging technique for making corrosion thinning determinations on aging aircraft skins. The technique uses pulsed surface heating and fast, synchronous IR imaging of subsurface structure, such as skin corrosion and disbonded doublers or tear straps. Sensitivity to corrosion thinning of less than two percent is demonstrated. Practical implementation of a simplified numerical measurement algorithm is presented, and the results are compared with profilometry and ultrasonic measurements of calibration standards. Examples are presented of thermal wave imaging of fuselage skin corrosion of a B737 testbed aircraft in a hangar environment at the FAA's Aging Aircraft NDI Validation Center.
Inhibition of neuronal firing in murine striatal slices by cyclodiene insecticides is mediated by release of dopamine and not GABA antagonism

Abstract This study investigated the effects of dieldrin and heptachlor epoxide, members of the cyclodiene class of insecticides, on neuronal firing in murine brain slices. The cyclodienes are environmentally persistent and human exposure to these compounds still occurs. Major physiological effects of cyclodienes include: (1) blockage of 3 GABA A receptors and (2) facilitation of neurotransmitter release with specificity for release of dopamine. Extracellular recordings were used to compare the effects of the cyclodienes to those of the prototypical GABA antagonist, picrotoxinin, on firing rates of striatal neurons. Recordings were made from cells that were inhibited by exogenously applied dopamine, which is an ideal neural substrate for differentiating effects on dopamine release from GABA antagonism. Low micromolar concentrations of cyclodiene caused depression of firing, inconsistent with GABA antagonism. Alternatively, application of picrotoxinin produced a consistent neuronal excitation in slices. The inhibitory action of dieldrin was blocked by the dopamine receptor antagonist fluphenazine, verifying the fact that cyclodiene-released dopamine was mediating the observed depression of striatal neurons. These results suggest that the ability of cyclodienes to evoke neurotransmitter release, especially dopamine, may significantly contribute to the neurotoxicity of these compounds, in vivo.
Development of a modal emissions model for a hybrid electric vehicle

With the growing market share of hybrid electric vehicles (HEVs), new methods are needed for estimating their actual energy use and emissions in order to support emission inventories. This research quantifies criteria associated with startup and shutdown of the internal combustion engine (ICE) for a 2001 Toyota Prius HEV and develops a modal tailpipe emissions model under hot stabilized conditions. The engine is found to be “off” below thresholds of engine power demand that are speed and acceleration dependent. Vehicle specific power (VSP) is used as the basis for modeling emissions. The predicted cycle emissions of CO, NOx and HC for individual cycles are subject to large relative errors, but the overall emission predictions for the average of multiple cycles have relative errors within 10% for each selected pollutant. The ICE engine status identification method is recommended for application to model HEV emissions under actual driving conditions.
Sdc2 and Tbx16 regulate Fgf2-dependent epithelial cell morphogenesis in the ciliated organ of asymmetry.

Heparan sulfate proteoglycans (HSPGs) control many cellular processes and have been implicated in the regulation of left-right (LR) development by as yet unknown mechanisms. Using lineage-targeted knockdowns, we found that the transmembrane HSPG Syndecan 2 (Sdc2) regulates LR patterning through cell-autonomous functions in the zebrafish ciliated organ of asymmetry, Kupffer’s vesicle (KV), including regulation of cell proliferation and adhesion, cilia length and asymmetric fluid flow. Exploring downstream pathways, we found that the cell signaling ligand Fgf2 is exclusively expressed in KV cell lineages, and is dependent on Sdc2 and the transcription factor Tbx16. Strikingly, Fgf2 controls KV morphogenesis but not KV cilia length, and KV morphogenesis in sdc2 morphants can be rescued by expression of fgf2 mRNA. Through an Fgf2-independent pathway, Sdc2 and Tbx16 also control KV ciliogenesis. Our results uncover a novel Sdc2-Tbx16-Fgf2 pathway that regulates epithelial cell morphogenesis.
The EuNi5-H system

Abstract The EuNi 5 -H system was examined using pressure-composition-temperature ( p - c - T ) methods and in situ X-ray diffractometry. One compound hydride (EuNi 5 H 5.5 ) is formed with ΔH = 26.4 kJ (mol H 2 ) −1 and ΔS = 128.5 J K −1 ( mol H 2 ) −1 obtained from the p - c - T data. The diffraction pattern can be indexed on a hexagonal lattice with a = 5.4519(21) A , c = 4.2354(24) A and V = 109.02 A 3 . The system characteristics, which include an exceptionally large value of 4.7 A 3 for ΔV per hydrogen atom, a very large pressure hysteresis and high ( x = 0.6) residual hydrogen at 298 K, are compared with those of the CaNi 5 -H and other AB 5 -H systems.
Cross-link induced linear and curved polymer channel waveguide arrays for massively parallel optical interconnects

A single-mode polymer-based channel waveguide array with 1250 channels/cm packaging density on a cross-link induced photopolymeric thin film is reported. This array works at 1.31 micrometers and 0.63 micrometers . Curved waveguides with radii of curvature (ROC) from 1 mm to 40 mm were demonstrated. Waveguide propagation loss in the neighborhood of 0.1 db/cm was demonstrated for both linear and curved waveguides. Interconnectivity for various interconnection architectures including cross bar, hypercube, daisy chain and star are further considered. Multiple layers of optical interconnects may be required for an optical backplane involving massively parallel highly distributed computing systems.
Kappa-Carrageenan Effects on the Gelation Properties of Simulated Oven-roasted Turkey Breast Juice

The gelling mechanism in oven-roasted turkey breast juice and the effects of k-carrageenan and certain salts were evaluated. In the presence of 2.2% salt and 0.5% phosphate, the soluble protein started to gel at 52°C, and k-carrageenan started to swell at 46°C during heating and gel at 44°C during cooling. When sodium chloride content was changed to 0% or 4.4% and phosphate content to 0% or 1.2%, k-carrageenan started to swell at 28°C and gel at 36°C, or swell at 67°C and gel at 55°C, respectively. The protein and k-carrageenan combination showed a significant (P<0.05) synergistic increase in final gel strength; the effect was increased further (P<0.05) by 0.2% added potassium chloride or calcium chloride.
First-Principles Periodic Density Functional Study of the Hydrogenation of Maleic Anhydride to Succinic Anhydride over Palladium(111)

Gradient-corrected periodic density functional (DFT) calculations were carried out in order to examine the hydrogenation of maleic anhydride to succinic anhydride via a Horiuti-Polanyi like mechanism on the well-defined Pd(111) surface. Reaction path calculations were performed at a surface coverage of maleic anhydride corresponding to 0.11 monolayer. The hydrogenation of maleic anhydride to the maleic anhydryl surface intermediate was found to have the highest intrinsic barrier (+95 kJ/mol) on Pd(111), of all the elementary steps involved in the hydrogenation of the olefinic group of maleic anhydride. This step is endothermic by 17 kJ/mol. Calculations indicate that the second step in the mechanism, the hydrogenation of maleic anhydryl to succinic anhydride, has a slightly lower barrier (+89 kJ/mol) and is exothermic by 37 kJ/mol. In an effort to understand the effect of change in the electronic properties of the metal on the intrinsic barrier for maleic anhydride hydrogenation, the C−H bond formation re...
Threshold effect in second-stage acceleration

Proton fluxes observed at Earth (van Hollebeke et al., 1975) have a much flatter size distribution than do other parameters of solar flares more representative of total energy. Peak proton flux varies at least as rapidly as the fourth power of total flare energy. An absolute threshold may exist, in view of the flatness of the proton distribution.
Motion control of a mobile robot traveling in a convoy using fuzzy logic

In many applications, the use of multiple robots of different capabilites will be desirable. In a teaming approach, multiple robots will cooperate to accomplish a task which a single robot alone is incapable, inefficient, or impractical at performing. When multiple robots are deployed, the motion of each robot may have to be coordinated with the rest of the robots. This paper deals with development of a fuzzy logic based motion controller for convoying the coordinated motion between a leader and a follower. The fuzzy logic based real-time motion controller uses relative distance and speed information to adust the speed of the trailing robot to smoothly follow the leader without either collisions or loosing sight of it. The performance and robustness of the system has been verified in a series of extensive laboratory trials.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Spectroscopic Investigations of ADMA Encapsulated in Pyrogallol[4]arene Nanocapsules

Pyrogallol[4]arenes form stable hydrogen-bonded nanocapsules that have unique properties that may make them suitable for diverse applications, such as catalysts and molecular transporters. Little is known about the behavior of the interior of these new materials in solution, and by using the solvent-dependent properties of 1-(9-anthryl)-3-(4-dimethylaniline) propane (ADMA), the inner phase properties of the hexamers are investigated. Steady-state and dynamic spectrofluorometric results are in agreement, are consistent with solid-state studies, and indicate that the majority of ADMA is sequestered in an extended conformation with the crystallization solvent. The conformational flexibility of ADMA is attributed to lower capsule occupancies (∼50%, i.e., 1 molecule per 2 capsules, one occupied and one empty) relative to our previous study with pyrene butyric acid (occupancy of 150%, i.e., 1.5 molecules per capsule) in which the probe was restricted within a nanocapsule. The nature of the encapsulated ADMA com...
On recent existence theorems in the theory of optimization

A condition recently proposed is shown to imply the weak compactness inH1,1 and actually is equivalent to another condition previously proposed by the authors. Once compactness is proved, then existence theorems follow from lower closure theorems also previously proved by the authors, and extended to Pareto problems. The present analysis adds to the recent work of Goodman concerning the equivalence of seminormality conditions with concepts of convex analysis and lattice theory.
The effects of incorrect specification of the Minkowski metric: Some analytical results

This article investigates the consequences of incorrectly specifying the Minkowski metric. Five theorems are developed which hold if the true and assumed spaces have the same axis orientations. If is further shown that four of these theorems hold only for the special Euclidean case when the axis orientations of the true and assumed spaces are different. A second part of this study, scheduled to be published in the Fall issue of this journal, investigates the sensitivity of the TORSCA nonmetric multidimensional scaling algorithm to incorrect specification of the Minkowski metric and the ability of Kruskal's “stress” measure to detect such incorrect specification.
Performance-Based Design Applied Analysis of Large-Scale Commercial Complexes

With the urbanized development, large-scale commercial complexes emerge rapidly in which many constructive shapes and formats distribution exist. However, the current design of fire protection code is unable to stipulate them. Although it really resolved many difficulties in the engineering practice using the performance of fire protection design, it has also brought many problems like circumventing the standard requirement, derating fire load by choosing fire scenes at will, reducing safety standards due to depending on the management excessively, choosing technical parameter randomly, losing contact with reality in the evaluation analysis and so on. So people need to put forward the control of performance design application scope after analyzing some performance-based design cases of some large-scale commercial complexes, to determine the security goal combining the condition of our country and the safety management, to select the fire scenes objectively and actually and to formulate and improve the current standards after summarizing the performance design measures of the indoor commercial pedestrian streets and the large and middle-scale atriums even the common architectural shapes.
An educational moment

This is a time of extraordinary opportunity for the US physics community. We have successively been urged by reports from Congress, the business community, the National Academy of Sciences, and the executive branch to expand innovation in the physical sciences, with the eventual goal of improving the economy. The proposed effort has two arms: increased activity in research and an enhancement of Americans’ educational attainments in math and physical sciences. There is a clear path toward the first goal based upon reversing the decline in federal and industrial funding of U.S.-based research. Here I make a few suggestions for how physicists might help improve education in the sciences and allied areas.
Immunogenicity in Weanling Rabbits of a Polyribophosphate Complex from Haemophilus influenzae Type b

Polyribophosphate (PRP), the capsular polysaccharide of Haemophilus influenzae type b, is more effectively immunogenic when it is associated with the bacterium than when it is in the purified form that is being tested as a vaccine for humans. In an effort to analyze this difference, we isolated from H. influenzae type b a high-molecular-weight, soluble complex, in which PRP appears to be combined with protein (about 7% protein). The pyrogenicity and limulus lysate gelation activity of the complex suggest that a small amount of lipopolysaccharide also is present. The protein was resolved into five polypeptides by electrophoresis in polyacrylamide gel containing sodium dodecyl sulfate. In weanling rabbits, which do not respond to purified PRP, the complex induces high titers of antibody of PRP, in an anamnestic pattern. Bactericidal antibody to other bacterial components was also elicited. Equilibrium density gradient centrifugation of the complex indicated that most of the immunogenicity of PRP resides in the least dense fractions, which are high in protein, low in polysaccharide, and active in the limulus lysate test; denser fractions that react strongly with limulus lysate but are poor in protein were much less immunogenic.
Age-related changes in immune function: effect on airway inflammation.

Immunosenescence is defined as changes in the innate and adaptive immune response associated with increased age. The clinical consequences of immunosenescence include increased susceptibility to infection, malignancy and autoimmunity, decreased response to vaccination, and impaired wound healing. However, there are several immune alterations that might facilitate persistence of asthma into late adulthood or development of asthma after the age of 50 to 60 years. Asthma in older patients is not uncommon, and this is a growing population as the average lifespan increases. Specific innate changes that might affect severity of asthma in older patients or be involved in the development of late-onset asthma include impaired mucociliary clearance and changes in airway neutrophil, eosinophil, and mast cell numbers and function. Additionally, age-related altered antigen presentation and decreased specific antibody responses might increase the risk of respiratory tract infections. Respiratory tract infections exacerbate asthma in older patients and possibly play a role in the pathogenesis of late-onset asthma. Furthermore, cytokine profiles might be modified with aging, with some investigators suggesting a trend toward T H 2 cytokine expression. This review examines specific innate and adaptive immune responses affected by aging that might affect the inflammatory response in older adults with asthma.
Homework for Students with Learning Disabilities The Implications of Research for Policy and Practice

The literature on homework for students with learning disabilities is reviewed. First, a summary of Cooper's (1989a) synthesis of research on homework for students without disabilities is presented, including (a) a definition of homework, (b) a model of the homework process, (c) the results of a meta-analysis of homework studies, and (d) generic policy guidelines. Next, special education research on homework conducted after 1985 is described. The literature is divided into studies that manipulated homework conditions and homework-related surveys of teachers and parents. The results of the literature review suggest that homework policies and practices for students with learning disabilities should emphasize (a) simple, short assignments; (b) careful monitoring by and prominent rewards from teachers; and (c) parental involvement, especially to provide structure, conducive environments, and immediate rewards.
FT-IR Spectra Analysis toward Cancer Detection

Computer-based research on cancer detection utilizes various types of data including MRI images, proteins and DNA. In this work, we investigate Fourier-transform infrared (FT-IR) spectra obtained from colon tissues as an alternative method to detect cancer. Fourier-transform infrared (FT-IR) spectra reflect the chemical composition of a source medium and hence provide utility for a wide range of applications including biology and medical science. They are characterized by high dimensionality and being prone to noise. In this paper, we present a study of machine learning algorithms to investigate the validity of FT-IR spectra for cancer detection. The Back-propagation neural network, the Decision tree, the Adaboost with decision tree, and the Support Vector Machine (SVM) algorithms were applied to 894 spectra in supervised learning. Of these algorithms, SVM held the most promise in binary classification. This result demonstrated the potential of FT-IR spectra in cancer research and the potential of SVM in spectra analysis.
Trichocereus pachanoi—A mescaline cactus used in folk healing in Peru

In north coastal Peru, a mescaline cactus called San Pedro (Trichocereus pachanoi2) is employed by folk healers in the diagnosis and cure of illness. Although such practices have been miientioned by Gutierrez-Noriega (3), Gutierrez-Noriega and Cru'z Sanchez (4), Friedberg (1, 2), Lastres (5), and Schultes (6), no discussion has dealt adequately with the ethnobotanical aspects of such drug use in a healing context. During the summer of 1967, under the aegis of the Institute of Social Psyehiatry3 of San Marcos University, Lima, I was fortunate to be able to eonduct an anthropological pilot study of a coastal Mestizo village some 500 miles north of Lima, where folk healing using this psychodysleptic substance is a specialized sphere of activity. In this small agricultural community, which will be called Valleseco (a pseudonym), located in the Department of Lambayeque, it is reputed that over 100 men and 3 womiien are actively engaged in the diagnosing and curing of illness in a practice inextricably linked to the use of Trichocereus pachanoi. Although my study was designed to relate folk healing to the social structure of the community, some of the data that I obtained may be of interest to ethnobotanists. At the time of *this writing, further interdisciplinary studies are being conducted to deal with subjective aspects of the use of this cactus. I will limit my remarks to the more general area of belief systems concerning
The patch microstructure in concrete: effect of mixing time

It has been previously shown by backscatter-mode scanning electron microscopy (SEM) that various laboratory- and field-mixed concretes exhibit dense areas or patches of hardened cement paste (hcp) alternating with highly porous areas or patches. The present work represents an effort to establish whether this distinctive microstructure was a result of inadequate mixing. A conventional laboratory concrete was prepared and subjected to prolonged mixing in an efficient pan mixer, with small samples being removed periodically, compacted, and cured for 28 days. Examination indicated that evidences of the patchy microstructure persisted despite prolonged mixing for up to 30 min, far beyond normal concrete mixing times.
Numerical and experimental study of vibration mitigation for highway light poles

Highway light poles are slender structures usually characterized by low values of structural damping, a factor that can lead to large-amplitude vibration sometimes leading to collapse. This paper is motivated by a recent investigation, conducted to identify the reason for repeated failures, experienced by aluminum tapered light poles in the State of Illinois during a winter storm. The study combined numerical and experimental full-scale analysis of the structural system and its response to simulated external actions. It was observed that, despite the simple structural form, the definitive identification of the mechanism causing the oscillations was challenging due to inherent variability in the configuration as well as the paucity of environmental and response data. However, a plausible mechanism was identified, and a mitigation technique was proposed and evaluated for amplitude reduction.
Contextual influences on self-control of is professionals engaged in systems development

Abstract In today's turbulent business environment, there is a move away from traditional hierarchical relations and governance within organizations, and a move toward increased reliance on self-control, where an individual sets his own goals, monitors his own work, and rewards or sanctions himself accordingly. Since the use of self control is often recommended in an environment of task complexity and ambiguity, systems development would seem to provide an excellent context in which to study it. The goal of this research is to examine contextual factors (work unit structure and knowledge technology) that influence IS project leaders' perceptions of self-control. To meet this goal, two studies were carried out: a survey of IS professionals and a series of three case studies of systems development efforts. Overall, the results suggest that IS project leaders' perceptions of self-control are highest when they have considerable job experience, when they are able to further refine existing development procedures, and when they are involved in smaller, less-complex systems development projects. Implications for the practice of systems development are discussed.
Consolidation dynamics of tungsten powder during dry bag cold isostatic pressing

Abstract Compaction of metal powders into billets for sintering is commonly accomplished by die pressing or isostatic pressing. The present paper describes the consolidation dynamics of tungsten powder during cold isostatic pressing. Tungsten powder was consolidated using pressures from 14–211 MPa at pressurization rates between 2 and 10 MPa/s. Elastic relaxation of tungsten compacts during decompression after pressing is an important phenomenon since it is a common cause of defects in pressed compacts. The increase in elastic relaxation during decompression of compacts pressed at pressures from 14 to 211 MPa is also described. The elastic relaxation increased from 0·13% at 14 MPa to 0·55% at 211 MPa. Some heating of the compact occurs during isostatic compaction due to friction between the powder particles, leading to a temperature increase of ≈ 10°C in the compact. The effect of pressurization rate on the heat generated is also described.
Developmental change in red blood cell volume: Implication in screening infants and children for iron deficiency and thalassemia trait*

The mean corpuscular volume when determined by electronic counter is an accurate tool for identification of children with microcytosis due to either iron deficiency or thalassemia trait. The purpose of this report is to describe the normal developmental changes in MCV that occur in children after 6 months of age. In 211 healthy infants and children screened to exclude those with borderline or overt iron deficiency, thalassemia trait, or hemoglobinopathy, we found that the lower limit of normal for MCV is 70 fl between 10 and 17 months of age and that there is a gradual increase of MCV with age; the lower limit is 74 between 1 1/2 and 4 years and 76 between 4 and 7 years. All of these values are well below the minimum adult level of 80 fl.
What's Best for Students? Comparing the Effectiveness of a Traditional Print Pathfinder and a Web-based Research Tool

This quantitative study compared a print pathfinder and a web-based research tool in library instruction for two sections of a first-year business course. The traditional print pathfinder received higher ratings on use, ease of use, and helpfulness, but both tools resulted in students citing a similar number of recommended sources.
Library screening for synthetic agonists and antagonists of a Pseudomonas aeruginosa autoinducer

The autoinducer (AI) that initiates the quorum sensing (QS) signaling cascade in Pseudomonas aeruginosa is an acyl-homoserine lactone (acyl-HSL). We initiated a study of the requirements for binding of the AI to its protein effector LasR by synthesizing a library of analogs with the HSL moiety replaced with different amines and alcohols. We tested each compound for both agonist and antagonist activity using a QS-controlled reporter gene assay and found several new agonists and antagonists. A representative antagonist was further tested for its ability to inhibit virulence factors. This data progresses our understanding of the LasR-AI interaction toward the rational design of therapeutic inhibitors of QS.
Obstacles to parent–adolescent communication in Hmong American families: exploring pathways to adolescent mental health promotion

ObjectiveMental health challenges disproportionately affect children in refugee families, with Hmong American adolescents being an extreme case (Thao, Leite, and Atella 2010). Limited understanding about the processes associated with this enhanced risk for children of refugees exists. Obstacles to parent–adolescent communication may contribute to this increased risk (Laursen and Collins 2004). This study's objective is to explore our limited understanding of parent–adolescent communication in refugee families by examining communication obstacles among Hmong Americans.DesignThirty Hmong American young adults (18 to 25 years; mean = 21.2, 50% female or n =15) participated in interviews that focused retrospectively on the parent–adolescent relationship.ResultsResults revealed obstacles that were initiated by the adolescent, parent, and community. Two adolescent-focused sub-themes (emotional discomfort and psychosocial immaturity), five parent-focused sub-themes (parental judgment, parental intimidation, no b...
Visibility Near Intersection Partially Obscured by Vegetation

A technique has been developed to quantify the visibility of vehicles to drivers approaching, or stopped at, an intersection where vegetation intermittently blocks their clear line of sight. The technique yields visibility values associated with a specific intersection, movement of vehicles, and vegetative environment. A computer program developed around the technique allows a user to determine the effects of the size and locations of specific vegetative elements on the partial or total visibility of one vehicle from another vehicle's location. The software is used to analyze the effects of visibility from removing or modifying selected vegetation surrounding an intersection, or along the crossroads. The visibility technique is general and can be used in many types of visibility analysis. The paper provides an example using the technique to determine the visibility between moving crossroad vehicles. In another example the visibility that a driver stopped at a controlled intersection has of the crossroad and traffic on it is determined. The technique can be used alone or in conjunction with field observations for the planning or analysis of vegetation effects on intersection visibility ranging from residential to forest settings.
Detection of quantitative trait loci for seminal root traits in maize ( Zea mays L.) seedlings grown under differential phosphorus levels

Suboptimal phosphorus availability is a primary constraint for terrestrial plant growth. Seminal roots play an important role in acquisition of nutrients by plant seedlings. The length and number of seminal roots may be particularly important in acquisition of immobile nutrients such as phosphorus by increasing soil exploration. The objective of this study was to identify quantitative trait loci (QTL) controlling seminal root growth in response to phosphorus stress in maize, and to characterize epistatic interactions among QTL. Seminal root length and number were evaluated in 162 recombinant inbred lines derived from a cross between B73 and Mo17 in seedlings grown in a controlled environment. B73 and Mo17 significantly differed for seminal root length under low phosphorus, but not under adequate phosphorus conditions. Seminal root length of the population grown under low phosphorus ranged from 0 to 79.2 cm with a mean of 32.3 cm; while seminal root length of plants grown under high phosphorus ranged from 0.67 to 59.0 cm with a mean of 23.4 cm. Under low phosphorus, one main-effect QTL was associated with seminal root length and three QTL with seminal root number; under high phosphorus, two QTL with seminal root length and three QTL for seminal root number. These accounted for 11, 25.4, 22.8, and 24.1% of the phenotypic variations for seminal root length and number at low phosphorus, and seminal root length and number at high phosphorus, respectively. Di-genic epistatic loci were detected for seminal root length at low phosphorus (two pairs) seminal root number at low phosphorus (eight pairs), seminal root length at high phosphorus (four pairs), and seminal root number at high phosphorus (two pairs), which accounted for 23.2, 50.6, 32.2, and 20.3% of the total variations, respectively. Seminal root traits observed here were positively yet weakly correlated with shoot biomass in the field under low phosphorus, although no coincident QTL were detected. These results suggest that epistatic interactions are important in controlling genotypic variation associated with seedling seminal root traits.
Superplumes or supercontinents

I attribute the Cretaceous pulse of Pacific oceanic crust formation to a global plate reorganization associated with the breakup of Pangea and rapid growth and reorganization of the Pacific plate. The Cretaceous was characterized by widespread rifting, continental breakup, rapid spreading, and global magmatism. Tomography shows that the upper mantle of the Pacific and Indian oceans is hot. These large low-velocity regions contain most of the world's hotspots and ridges and were the sites of extensive plateau and continental flood-basalt magmatism. The formation and rapid expansion of the Pacific and Indian ocean plates took place in these regions that are hot because they have not been cooled or displaced by cold oceanic lithosphere for more than 200 m.y. Plumes are not required to explain such mantle. The Pacific hemisphere is isolated from the supercontinent hemisphere by a band of cool mantle over which continents collect and into which subduction preferentially occurs.
Force system generated by an adjustable molar root movement mechanism

Introduction Tooth movement simulation is important for planning the optimal force system and appliance design to correct a specific malocclusion. Experimental verification of a 3-dimensional force system is described for a unique molar root movement strategy that can be adapted to many clinical scenarios. Methods The force system was measured for molar root movement springs that had adjustable alpha (anterior) and beta (posterior) moments. A 3-dimensional transducer assessed moments and forces in 3 planes during deactivation and simulated molar rotation. Two experimental situations were compared by using 10 springs in each group: spring reactivation was performed to compensate for changes in the force system caused by molar movement, or there was no reactivation. Results Without reactivation, the force system becomes unfavorable after approximately 5° of molar movement (rotation). With reactivations, a favorable force system through 20° of molar movement is maintained. Conclusions Present root-movement appliances require periodic adjustment to achieve optimal tooth movement. Additional studies are needed to design orthodontic appliances for delivering optimal force systems for the entire range of tooth movement.
Reaction time to square-wave gratings as a function of spatial frequency, complexity and contrast

Visuomotor reaction time (RT) of normal human subjects to briefly presented square-wave bar patterns were measured. The pattern varied with respect to magnitude and number of spatial frequencies (one cycle/degree of visual angle, 3 cycles/degree, and both combined) with each spatial frequency stimulus presented at 3 levels of contrast. Space-average luminance was held constant. RT increased with the higher spatial frequency and was intermediate in value for the combination stimulus at each level of contrast. RT increased with decreasing contrast levels for each spatial frequency stimulus. There was no interaction between the two parameters. The findings indicate that a behavioral response measure can be employed to study the multiple channel hypothesis of human vision. The results were compared with those of other investigators employing sine-wave gratings, perceptual response measures and the evoked potentials technique.
Simulation of swing phase dynamics in above-knee prostheses

Abstract The paper presents a dynamic analysis of an above-knee prosthesis during the swing period of the walking cycle. The prosthesis consists of a four-bar knee mechanism with a pneumatic swing control unit. The kinematics of the knee joint, the dynamics of the leg, and the thermodynamics of the controller are analyzed. As predicted on the basis of the analysis, the behavior of the prosthesis compares well with experimental measurements. The analysis is useful in evaluating prosthetic devices during the design stage.
Imaging RNA in Single Living Cells: Recent Advances and Future Outlook

Recently, we developed an oligonucleotide-based probe for imaging RNA in living cells, i.e. Ratiometric BiMolecular Beacons (RBMBs). RBMBs are highly sensitive, exhibit little/no false-positives, and can be used for prolonged imaging of single RNA transcripts.
Populating Partially Unfolded Forms by Hydrogen Exchange-Directed Protein Engineering

The native-state hydrogen exchange of a redesigned apocytochrome b 5 6 2 suggests that at least two partially unfolded forms (PUFs) exist for this four-helix bundle protein under native conditions. The more stable PUF hasthe N-terminal helix unfolded. To verify the conclusion further and obtain more detailed structural information about this PUF, five hydrophobic core residues in the N-terminal helix were mutated to Gly and Asp to destabilize the native state selectively and populate the PUF for structural studies. The secondary structure and the backbone dynamics of this mutant were characterized using multidimensional NMR. Consistent with the prediction, the N-terminal region of the mutant was found to be unfolded while other parts of the proteins remained folded. These results suggest that native-state hydrogen exchange-directed protein engineering can be a useful approach to populating partially unfolded forms for detailed structural studies.
The next generation of science policy-makers.

Donald Kennedy “(Aftermaths,” Editorial, 29 Nov., p. [1679][1]) is wise to advocate new means of encouraging science and technology training for future policy-makers in the United States. The National Defense Education Act is an informative model, not least for its expansive view of the critical skills the United States would require. By focusing on educating the next generation of public servants, however, Kennedy addresses only a part of the United States' intellectual deficit and only part of our opportunity. In an era of dazzling opportunities across many scientific disciplines, our country has been disinvesting ([1][2]). Federally supported R&D shrank in 2000 to less than 0.7% of the gross domestic product—a level last seen before the Soviets launched Sputnik. A laudable bipartisan effort to double the NIH budget has nourished biomedical research and training, but a steady attrition of investment has weakened the physical sciences and engineering. The Department of Energy's funding for the physical sciences has decreased by 20% since 1993. The number of graduate students has dropped proportionately, with U.S. students minorities in many departments. While continuing to welcome foreign students and sustaining our enormously beneficial position as graduate school to the world, we must take new steps to encourage and support the advanced graduate studies of U.S. citizens in science and engineering. An ambitious new program of graduate fellowships—let us call them Benjamin Franklin fellowships—would show students that our country values science and technology and would spur them toward creative public service. Graduate students we attract during this decade will help shape the world for half a century, so it would be shortsighted to target a few specialties. It would be better by far to attract more of our best students to the most interesting sciences and to inspire them, like Benjamin Franklin, to range over pure and applied science, engineering, and even statecraft! 1. [↵][3]“Federal Investment in R&D,” a project memorandum prepared for the President's Council of Advisors on Science and Technology by the RAND Science and Technology Policy Institute and the AAAS (see [www.rand.org/publications/MR/MR1639.0/][4]). [1]: /lookup/doi/10.1126/science.298.5599.1679 [2]: #ref-1 [3]: #xref-ref-1-1 "View reference 1 in text" [4]: http://www.rand.org/publications/MR/MR1639.0/
A mutual information based double-talk detector for nonlinear systems

A reliable double-talk detector (DTD) is often a necessary requirement for acoustic echo cancellers (AECs). Various techniques have been proposed in the literature to detect double-talk for AEC systems. In those DTD algorithms, the acoustic echo path is assumed to be linear. On the other hand, nonlinear AEC is necessary when the system components such as loudspeakers exhibit nonlinearities. In this paper, we show that existing DTDs do not perform well when the acoustic echo path is nonlinear. We propose a novel DTD based on the mutual information (MI) concept and show that it performs well in the presence of nonlinearity. Effectiveness of the proposed method is demonstrated through computer simulations.