cssi/SciSciGPT-SciSciNet huggingface dataset:
Studies on biosynthesis of waxes by developing jojoba seed. II. the demonstration of wax biosynthesis by cell-free homogenates

The following enzyme activities were demonstrated in cell-free homogenates from developing jojoba cotyledons: 1) elongation of long chain acyl-CoAs in the presence of malonyl-CoA and NADPH (or NADH), 2) NADPH-dependent reduction of long chain acyl-CoAs to the corresponding alcohols, 3) esterification of long chain acyl-CoAs and the alcohols produced from them into wax, 4) elongation of stearoyl-ACP to eicosanoate and docosanoate as well as reduction to stearyl alcohol, 5) desaturation of stearoyl-ACP to oleate in the presence of reduced ferredoxin, and 6) incorporation of malonyl-CoA into long chain fatty acids and alcohols in the presence of added acyl carrier protein. These activities were associated entirely with the floating wax pad after centrifugation of the cell-free homogenate at 12,000 g for 20 min. The relevance of the above reactions (1–6) to wax biosynthesis in vivo is discussed. Production of oleate from acetate by enzymes utilizing ACP-thioesters as substrates followed by conversion of oleyl-ACP to oleoyl-CoA (via free oleic acid) for subsequent elongation, reduction, and esterification, is presented as the most probable in vivo pathway, for wax biosynthesis. The substrate specificities of the elongation and reduction reactions utilizing acyl-CoAs as substrates are examined in terms of wax composition.
Trapping of feral honey bee workers (Hymenoptera: Apidae) in a coastal prairie landscape: effects of season and vegetation type.

Nous avons examine les taux de capture d'ouvrieres d'abeilles domestiques (Apis mellifera L.) au cours de l'annee et compare les taux de capture dans quatre communautes vegetales differentes. Les taux de capture varient pendant l'annee et le plus grand nombre d'abeilles est recolte de decembre jusqu'en fevrier alors que la disponibilite du nectar et du pollen est basse. Les taux de capture varient aussi en fonction des communautes vegetales. Les pieges places dans des communautes forestieres contiennent moins d'abeilles domestiques que ceux situes dans des communautes de chenes verts en fevrier ou dans des communautes de broussailles et de chenes verts en decembre, ce qui s'explique par des estimations de la disponibilite plus faible du nectar dans la foret. Peu d'abeilles ont ete capturees durant les periodes d'essaimage, ce qui indique que la plupart des abeilles recoltees etaient a la recherche de sources de nourriture. Le nombre d'abeilles domestiques capturees dans les pieges fournit une estimation qualitative de la disponibilite des ressources alimentaires. Les pieges peuvent aussi servir a recolter des insectes pour les analyses genetiques ou pour etudier la repartition spatiale et temporelle d'autres especes.
Criminal justice programs in higher education: Course and curriculum orientations

Abstract The growth of criminal justice education programs at institutions of higher learning has been largely a phenomenon of the 1960s and 1970s. This rapid growth has resulted in a variety of program types in terms of both subject area and content orientation. Programs appear to be moving toward a total-system approach with both a social science and professional emphasis. The type of program developed by educational institutions has implications for instructor selection, practitioner relationships, and organizational location within the institution of higher learning.
Aeroelastic analysis of sounding rocket vehicles

Rigid-body stability analysis can be extended to treat aeroelastic effects by allowing the structure to deflect under airloads as a simple beam. Linear aerodynamics and the bent shape then define the airloads. The resulting equations are indeterminant but can be manipulated to show the basic aeroelastic effects of flexibility, dynamic pressure, and angle of attack. The FLMD quasi-static program can solve these equations by iteration and compute stability for a specific vehicle/payload combination. Given the proper distributed inputs for the instant of time investigated, the FLMD predicts the center of pressure and related parameters, such as static margin.
Selective attention and the processing of integral and nonintegral dimensions: A developmental study

Abstract In two experiments, first- and fourth-grade subjects (age 6 and 9 years) performed a speeded card-sorting task with either integral or nonintegral dimensions. The dimensions were so arranged that subjects sorted on three types of task: (1) single dimension, (2) correlated dimensions, and (3) orthogonal dimensions. Results of the first experiment indicate that both first- and fourth-grade subjects sorted integral dimensions in a manner not qualitatively different from that of the adult ( Garner & Felfoldy, Cognitive Psychology , 1970 , 1 , 225–241). In comparison with single-dimension tasks, performance was facilitated on the correlated-dimensions tasks and interference was observed on the orthogonal-dimensions tasks. Performances with nonintegral dimensions revealed an age-related processing difference. Fourth graders sorted nonintegral dimensions like the adult; no differences in performance were observed between the tasks. In contrast, first-graders sorted nonintegral dimensions as if they were integral. Interference was consistently observed on orthogonal-dimensions tasks. On correlated-dimensions tasks, interference was observed on easy tasks and redundancy facilitated difficult tasks. In the second experiment, first graders showed consistent facilitation on the correlated-dimensions task; all other results were indentical to those of Experiment I. The results were interpreted as consistent with perceptual learning theory ( Gibson, Principles of perceptual learning and development . New York: Appleton-Century-Crofts, 1969 ).
Clival lesion incidentally discovered on cone-beam computed tomography: A case report and review of the literature

An osteolytic lesion with a small central area of mineralization and sclerotic borders was discovered incidentally in the clivus on the cone-beam computed tomography (CBCT) of a 27-year-old male patient. This benign appearance indicated a primary differential diagnosis of non-aggressive lesions such as fibro-osseous lesions and arrested pneumatization. Further, on magnetic resonance imaging (MRI), the lesion showed a homogenously low T1 signal intensity with mild internal enhancement after post-gadolinium and a heterogeneous T2 signal intensity. These signal characteristics might be attributed to the fibrous tissues, chondroid matrix, calcific material, or cystic component of the lesion; thus, chondroblastoma and chondromyxoid fibroma were added to the differential diagnosis. Although this report was limited by the lack of final diagnosis and the patient lost to follow-up, the incidental skull base finding would be important for interpreting the entire volume of CBCT by a qualified oral and maxillofacial radiologist. (Imaging Sci Dent 2014; 44: 165-9)
Size, Structure and Growth of the U.S. Information Economy

This paper presents the results of our empirical research in measuring the size and structure of the U.S. information economy in 1992 and 1997, and in assessing the growth experienced by different industries and sectors since Porat’s research on the U.S. information economy in 1967. The study indicates that the share of the information economy in total GNP grew from about 46 percent in 1967 to about 56 percent in 1992, and to 63 percent in 1997. The study further indicates that during this time period the share of service sector information activities in total GNP increased substantially, while the shares of non-service sectors declined correspondingly. The industries displaying the highest growth rates include business services, and medical and educational services. The paper also provides a critical assessment of Porat’s methodology and suggests specific improvements that may be made to obtain a more plausible measure of the size and structure of the information economy.
Flying by Ear: Blind Flight with a Music-Based Artificial Horizon

Two experiments were conducted in actual flight operations to evaluate an audio artificial horizon display that imposed aircraft attitude information on pilot-selected music. The first experiment examined a pilot's ability to identify, with vision obscured, a change in aircraft roll or pitch, with and without the audio artificial horizon display. The results suggest that the audio horizon display improves the accuracy of attitude identification overall, but differentially affects response time across conditions. In the second experiment, subject pilots performed recoveries from displaced aircraft attitudes using either standard visual instruments, or, with vision obscured, the audio artificial horizon display. The results suggest that subjects were able to maneuver the aircraft to within its safety envelope. Overall, pilots were able to benefit from the display, suggesting that such a display could help to improve overall safety in general aviation.
Giant scrotal lipomatosis.

A 38-year-old morbidly obese man presented with a gradually enlarging groin mass, difficulty walking and a 100pound weight gain in the last year. He had no other gastrointestinal or constitutional symptoms, and no specific scrotal pain or voiding symptoms. Physical examination revealed weight 500 pounds and a 21 x 22 X 24 cm. mass in the left hemiscrotum (fig. 1). "he left testicle was not palpable and the mass did not transmit light. Bowel sounds were not audible over the mass. The right hemiscrotum was normal and contained a normal testicle. The penile shaft was not visible secondary to obesity. Remainder of the physical examination was unremarkable. Sonography revealed a heterogeneous solid mass. Serum P-human chorionic gonadotropin and a-fetoprotein were in the normal range (less than 1 mIU/ml. and less than 15 ng./ml., respectively). Left hemiscrotectomy was performed with the patient under spinal anesthesia. Body habitus precluded an inguinal
Heterogeneous electron behaviour in a turbulent plasma jet

Uncommonly large electron density fluctuations, accompanied by large skewness and flatness factors, have been observed in the transitional zone of a plasma jet. These effects are investigated further by a digital analysis of Langmuir probe signals from this zone. The electron aggregate is found split into a decaying laminar-fluid remnant and a growing population of turbulent fluid. The uncommon statistics are caused by the double-humped histogram, while those of each population separately are normal. The mean electron density of the aggregate displays no simple chemical decay trend, but that of the laminar population fits known argon recombination schemes. (auth)
Clinical findings among young women with genital human papillomavirus infection

OBJECTIVE: The purpose of this study was to identify clinical signs and symptoms associated with detection of human papillomavirus (HPV) DNA in the female genital tract. STUDY DESIGN: A total of 516 university students (18 to 24 years old) enrolled in a cohort study that included the collection of genital specimens for HPV DNA testing every 4 months for up to 4 years. Reported symptoms and objective clinical findings of women with and without HPV DNA were compared by multivariate analysis. RESULTS: Acute and persisting HPV infections were not associated with discharge, itching, burning, soreness, or fissures. Clinical evidence of genital warts was statistically associated only with HPV types 6 and 11. Detection of any HPV DNA was associated with bacterial vaginosis (BV). Furthermore, a time lag analysis suggests that HPV infection usually precedes detection of BV. CONCLUSION: Most women who acquire genital HPV infection are asymptomatic; some, however, are at increased risk for BV.
Achieving resonance in a congenital heart team

Abstract To improve outcomes in congenital heart care, and create a more satisfying work environment for our congenital heart team, we have focused on achieving states of resonance in two areas—clinical care and information management. The common pathway to achieving these different states of resonance was the constant adoption and creation of new technology. We defined clinical resonance as a state of strategic synchrony in the therapeutic approach to each patient presented to the team for congenital heart treatment. We felt that boundaries between subspecialties might inhibit progress, and focused on developing a unified approach to a number of congenital lesions. We synthesized techniques in conventional surgery, minimally invasive surgery, and interventional catheterization to create a series of hybrid approaches. The overall goal of each therapeutic plan was designed to minimize the cumulative trauma to each patient over their lifetime. A strategy for information technology development was devised, using an on site technology advisor to facilitate the integration of numerous cardiac team information sources. A series of tools were created and adopted by the cardiac team, to achieve information resonance. Information technology was used to measure clinical performance, and facilitate rapid clinical information sharing between all members of the extended congenital heart team. Our current information technology platform is an Internet based medical information system, integrating diverse clinical databases on the World Wide Web.
The electron capture cross section of 1.5–3 MeV protons from carbon

Abstract Since single collision conditions for electron capture processes cannot be obtained for solid carbon targets, gaseous carbon compounds (CH 4 , C 2 H 2 , C 2 H 4 , C 3 H 6 , C 3 H 6 , and C 4 H 8 ) were used as targets to determine the electron capture cross sections of protons from carbon. Although the statistical uncertainty of the measurement was less than 1%, the pressure determination limited our absolute accuracy to 10–15%. Within this uncertainty, the electron capture cross sections of protons from carbon was independent of the carbon compound used in the experiment. The measured cross sections were 8.6 × 10 −21 , 3.0 × 10 −21 7.4 × 10 −22 cm 2 /atom for proton enrgies 1.5, 2, and 3 MeV respectively.
Rigorous Interdisciplinary Pedagogy: Five Years of ACE

The emergence of media-arts and digital cultural practices has provided a highly charged context for the development of interdisciplinary pedagogy, combining as it does, practices and traditions from historically, culturally and theoretically wildly divergent disciplines. This article addresses aspects of effective interdisciplinary educational process, attending to questions of pedagogy, theory and institutional pragmatics. In my analysis, the key components of such a project are: deep technical training and understanding; deep training in artmaking and cultural practice; deep theoretical and historical contextualization, and an open and rigorous interdisciplinary context which maximally facilitates the negotiation of these often divergent ways of thinking and making. In building such interdisciplinary practice in the context of a campus, one abruptly confronts the discontinuity between the rapidly changing fluidity of the contemporary moment and the relative stasis of institutionalized disciplines which...
XXXIX.—The Carboniferous insects of Maryland

(1927). XXXIX.—The Carboniferous insects of Maryland. Annals and Magazine of Natural History: Vol. 19, No. 112, pp. 385-416.
Half-lives of 204Tl and 134Cs

Abstract Ionization measurements extending over a period of 6·3 years have yielded half-lives of 4·11 ± 0·13 years for 204 Tl and 2·26 ± 0·05 years for 134 Cs.
Estudio preliminar de la flora liquénica de Isla Mocha, sur de Chile

La micobiota liquenizada de Isla Mocha, sur de Chile, esta representada por 76 especies en 30 generos; el 38 % de las especies son endemicas del sur de Sudamerica. Xanthoria parietina, registrada en todas las zonas de muestreo, y Pseudocyphellaria malmeana recolectada solo en el bosque de Aextoxicon punctatum, son las especies mas representativas. Ramalina fastigiata constituye un nuevo registro para Chile.
Patient and surgeon decision making regarding surgery for advanced cancer

PURPOSE/OBJECTIVES To describe a program of research related to outcomes of palliative surgery and focus on one phase of this research involving decision making by patients and surgeons considering surgery for advanced disease. DESIGN Descriptive. SAMPLE 10 patients undergoing surgery and 3 oncology surgeons. METHODS Qualitative interviews were conducted with patients and their surgeons pre- and postoperatively. Transcripts were content analyzed to identify major themes in patient and surgeon interviews based on study questions. MAIN RESEARCH VARIABLES Decision making, palliative surgery, quality of life. FINDINGS The study findings highlight the issues of greatest concern to patients and surgeons considering palliative surgery. This phase was an important component of the overall program of palliative surgery research. CONCLUSIONS Comprehensive care for patients with advanced cancer seeks to achieve a balance of providing aggressive care, ensuring optimum symptom management, and maintaining a focus on comfort. Further study of palliative surgery as an aspect of interdisciplinary care is warranted. IMPLICATIONS FOR NURSING Patients undergoing surgery for advanced disease require expert nursing care to address quality-of-life concerns. Further research is needed in this area.
Development of Pattern Recognition Software for Tracks of Ionizing Radiation In Medipix2-Based (TimePix) Pixel Detector Devices

The principal aim of our project is to develop an efficient pattern recognition tool for the automated identification and classification of tracks of ionizing radiation as measured by a TimePix version of the hybrid semiconductor Medipix2 pixel detector system. Such a software tool would have a number of applications including dosimeters to assess the risk of human exposure to radiation, and area monitors to characterize the general background radiation environment harmful to humans and electronic equipment. We are particularly interested in the development of the real-time analysis software needed to support an operational dosimeter that can assess the radiation environment during space missions. Our software development project makes use of data taken in beams of heavy ions at HIMAC (Heavy Ion Medical Accelerator Facility) in Chiba, Japan, including data from several different heavy ions with similar Linear Energy Transfers (LETs) for calibration purposes. We describe two modules of our pattern recognition tool: feature generation and classification. Our first module builds on a segmentation algorithm that identifies tracks from the pixel image assuming an approximately elliptical form that varies in size and degree of elongation based on multiple factors, including the particle species and angle of incidence. Determining the charge and energy of the particles creating each track is a particularly challenging task because different energy and charge incident particles can produce very similar patterns. Our classification module invokes different algorithms such as decision trees, support vector machines, and Bayesian classifiers.
Surface contact potential patches and Casimir force measurements

We present calculations of contact potential surface patch effects that simplify previous treatments. It is shown that, because of the linearity of Laplace's equation, the presence of patch potentials does not affect an electrostatic calibration of a two-plate Casimir measurement apparatus. Using models that include long-range variations in the contact potential across the plate surfaces, a number of experimental observations can be reproduced and explained. For these models, numerical calculations show that if a voltage is applied between the plates which minimizes the force, a residual electrostatic force persists, and that the minimizing potential varies with distance. The residual force can be described by a fit to a simple two-parameter function involving the minimizing potential and its variation with distance. We show the origin of this residual force by use of a simple parallel capacitor model. Finally, the implications of a residual force that varies in a manner different from $1/d$ on the accuracy of previous Casimir measurements is discussed.
Towards efficient query processing on massive time-evolving graphs

Time evolving graph (TEG) is increasingly being used as a paradigm for modeling and analyzing dynamic relationships in many emerging domains such as online social networks, World Wide Web and evolutionary genomics. A time-evolving graph consists of a sequence of snapshots of the graph as it evolves over time. The ability to scalably process various types of queries on massive TEGs is central to building powerful analytic applications for these domains. Unfortunately, indexing techniques and cluster computing schemes that have been designed for static graphs are not very effective for processing massive TEGs. Towards designing scalable mechanisms for answering TEG queries, this paper studies three important problems. The first is the distribution of TEG data on the nodes of a cluster computing framework such as Pregel or Giraph so that the computing and communication resources of the cluster are effectively harnessed. The second is the answering of reachability queries on any snapshot of a TEG and the third is that of processing pattern matching queries in TEGs. For each problem, we provide a brief literature survey and explain why trivial extensions of static graph techniques are not adequate for TEGs. We also present our preliminary ideas towards addressing these problems and discuss their benefits.
Using time of first positive HIV test and other auxiliary data in back-projection of AIDS incidence

Estimation of HIV incidence by the method of back-projection typically uses data on the time of diagnosis of AIDS cases, together with known information about the incubation distribution of AIDS. This paper discusses back-projection using auxiliary data on AIDS cases, particularly the time of first positive HIV test. We discuss the possibility that certain types of auxiliary data, including time of first positive test, can be useful in back-projection because they provide extra information about the incubation period of AIDS cases. Under a back-projection model, theoretical efficiency calculations are given comparing back-projection with and without the time of first positive HIV test of AIDS cases. These calculations suggest that such data have the potential to significantly improve HIV incidence estimates, particularly in the recent past. Smoothed non-parametric estimates of both HIV incidence and time-dependent testing rates are described. These can be obtained using the EM algorithm, in conjunction with a smoothing step or a penalized likelihood. The benefit of these methods in practice needs to be assessed as such data become available.
An Evaluation Procedure for a New Program to Prepare Administrator Change Agents

In this article the authors describe a new administrative preparation program which they conduct. They also discuss at some length a procedure developed for evaluating that program.
Scanner observations of selected cool stars

Photoelectric spectral scans at 30 A resolution of nine dwarfs, ten giants, and six supergiants with spectral types G0 to M5 are presented. (All stars were observed every 4 A from 3300 to 7000 A.) Absorption features observed at this resolution coincide with: strong atomic lines of Fe I, Fe II, Ca I, Ca II, Mg I, and Na I; vibrational bands of the electronic transitions of TiO, MgH, CaH, SiH, AlH, CN, CH, C2, OH, and NH. The dependences of the 3740-A Fe I blend and the 3440-A depression on temperature are discussed.
Enthusiasm: Collectiveness, Politics, and Aesthetics

From “Black Collectivities: A Conference,” held May 3–4, 2013, at Northwestern University’s Mary and Leigh Block Museum of Art, the Museum of Contemporary Art Chicago, and the University of Chicago’s Arts Incubator. This article begins with part of Elvira Dyangani Ose’s ongoing doctoral research into the recent upsurge of multidisciplinary and collective projects in Africa. It focuses on artists and artist collectives whose works intervene in everyday experience, emphasizing elements of the “common things” and questioning “the habitual.” Proceeding to a series of examples in modern Africa, the article uses Jean-Francois Lyotard’s notion of enthusiasm to explore in depth two case studies, Bessengue City Project and Chimurenga Library . Both initiatives incorporate the significance of the space where the art intervention is being produced and reflect the social relationships established there. Both look at modern African scenarios and propose new sociospatial paradigms.
Kriging bootstrapped neural network training for fast and accurate process variation analysis

Speeding up the design optimization process of Analog/Mixed-Signal circuits has been a subject of active research. Techniques such as metamodeling, artificial neural networks, and optimization over SPICE netlists have been used. While the results are accurate and promising, the effects of process variation on design space exploration still persist. Metamodels created by existing techniques are still not variation aware. This paper presents a novel technique for fast and accurate process variation analysis of nanoscale circuits. The technique combines traditional Kriging with an artificial neural network (ANN) to achieve the objective. Kriging captures correlated process variations of the circuits and accurately trains the ANN to generate the metamodels. The proposed technique uses Kriging to bootstrap target samples used for the ANN training. This introduces Kriging characteristics, which account for correlation effects between design parameters, to the ANN. As a case study of the proposed method, Kriging bootstrapped trained ANN metamodels are presented for an 180 nm Phase-Locked Loop (PLL) circuit design.
Using Robotis Bioloid systems for instructional Robotics

This is a report on our evaluation of Robotis' Bioloid robotic systems for their use in a senior-level engineering robotics course. We had found that Robotis had provided robust embedded C and LabView libraries that we were able to intermix, adapt and extend for our needs in sensor and actuator interfacing, especially in ZigBee applications to create a mobile wireless sensor network whereas the PC acted as the base station to 3 carbots sending back their NIR sensor data and the number of node hops needed for a data packet to get back to base. In the area of harmonizing multiple controllers on a single robotic platform, Robotis did not have tools readily usable for us, but we managed to develop a basic motion capture tool to work on a quadruped robot platform in a master-slave controllers configuration.
Outcome of Extracorporeal Membrane Oxygenation for Early Primary Graft Failure After Pediatric Heart Transplantation

Objectives We sought to analyze the indications and outcome of extracorporeal membrane oxygenation (ECMO) for early primary graft failure and determine its impact on long-term graft function and rejection risk. Background Early post-operative graft failure requiring ECMO can complicate heart transplantation. Methods A retrospective review of all children requiring ECMO in the early period after transplantation from 1990 to 2007 was undertaken. Results Twenty-eight (9%) of 310 children who underwent transplantation for cardiomyopathy (n = 5) or congenital heart disease (n = 23) required ECMO support. The total ischemic time was significantly longer for ECMO-rescued recipients compared with our overall transplantation population (276 ± 86 min vs. 242 ± 70 min, p Conclusions Overall survival was 54%, with all patients surviving to at least 3 years after undergoing transplantation. None of the children requiring >4 days of ECMO support survived. Despite an increased number of early and hemodynamically compromising rejections, the long-term graft function is similar to our overall transplantation population.
A retrospective review of clinical features and treatment outcomes in steroid-resistant interstitial lung disease from polymyositis/dermatomyositis.

Summary Introduction We reviewed our experience with immunosuppressive agents in patients with steroid-resistant Interstitial Lung Disease in the setting of Polymyositis/Dermatomyositis (PM/DM-ILD) to determine whether there were major differences in outcomes. Methods We identified all patients treated for PM/DM-ILD and assessed cyclophosphamide (CYC), azathioprine (AZA) and mycophenolate (MMF) when used as first-line steroid sparing therapy for effects on pulmonary function variables, dyspnea and tolerance at six and twelve months. Results Among 46 patients meeting the inclusion criteria, 24 were treated with CYC, 13 with AZA and 9 with MMF. There were no baseline differences between the three treatment groups for any of the demographic or physiologic variables, dyspnea score, the presence of >30% fibrosis on CT, or the baseline steroid dose. At the six months assessment, the overall median change in FVC was 5.0% (25th, 75th percentile −3, 11.5%), corresponding to +.20 L (.09, 0.42 L) and the DLCO increased by 2.93% (−4, 9%), corresponding to 1 mm/ml/Hg (−.58, 2.3). The severity of dyspnea decreased substantially, prednisone dose could be reduced and no important difference in side effects was found in the whole group of patients. This effect was sustained after twelve months of therapy. Conclusions In patients with PM/DM-ILD related, treatment with CYC, AZA or MMF was associated with stabilization of pulmonary physiology, improved dyspnea, and a reduction of steroid dose.
Revised U.S. nutrient management standard

A newly revised National Nutrient Management Standard could have “a continental impact on how we use nutrients” on potentially hundreds of millions of acres of farmland in the United States, Dave White, chief of the U.S. Department of Agriculture's Natural Resources Conservation Service (USDA/NRCS), said at a 13 December news briefing. NRCS uses the voluntary standard, which was last updated in 2006, to help producers better manage the application of nutrients—including fertilizers, animal manures, legumes, and crop cover—on agricultural land. Proper application of nitrogen and phosphorous is of particular concern, White said, adding that the new standard has an increased emphasis on the “four R's” of nutrient management: using the right amount of fertilizer and the right source, and applying the fertilizer in the right place at the right time. In addition, he said, the new standard emphasizes a number of technological tools for fertilizer and farmland management that have become available since the last update of the standards.
Crystal Structure of a Lipoxygenase in Complex with Substrate THE ARACHIDONIC ACID-BINDING SITE OF 8R-LIPOXYGENASE

Lipoxygenases (LOX) play critical roles in mammalian biology in the generation of potent lipid mediators of the inflammatory response; consequently, they are targets for the development of isoform-specific inhibitors. The regio- and stereo-specificity of the oxygenation of polyunsaturated fatty acids by the enzymes is understood in terms of the chemistry, but structural observation of the enzyme-substrate interactions is lacking. Although several LOX crystal structures are available, heretofore the rapid oxygenation of bound substrate has precluded capture of the enzyme-substrate complex, leaving a gap between chemical and structural insights. In this report, we describe the 2.0 A resolution structure of 8R-LOX in complex with arachidonic acid obtained under anaerobic conditions. Subtle rearrangements, primarily in the side chains of three amino acids, allow binding of arachidonic acid in a catalytically competent conformation. Accompanying experimental work supports a model in which both substrate tethering and cavity depth contribute to positioning the appropriate carbon at the catalytic machinery.
Phase-matching optima for high-order multiwave mixing and harmonic generation beyond perturbation limit

Abstract We demonstrate that the optimal phase-matching conditions for the high-order optical multiwave mixing and harmonic generation, which are given by the perturbation theory, remain valid in the strong-field limit under quite general assumptions about induced nonlinear polarization.
Transmembrane Neuregulins Interact with LIM Kinase 1, a Cytoplasmic Protein Kinase Implicated in Development of Visuospatial Cognition *

The neuregulins are receptor tyrosine kinase ligands that play a critical role in the development of the heart, nervous system, and breast. Unlike many extracellular signaling molecules, such as the neurotrophins, most neuregulins are synthesized as transmembrane proteins. To determine the functions of the highly conserved neuregulin cytoplasmic tail, a yeast two-hybrid screen was performed to identify proteins that interact with the 157-amino acid sequence common to the cytoplasmic tails of all transmembrane neuregulin isoforms. This screen revealed that the neuregulin cytoplasmic tail interacts with the LIM domain region of the nonreceptor protein kinase LIM kinase 1 (LIMK1). Interaction between the neuregulin cytoplasmic tail and full-length LIMK1 was demonstrated by in vitro binding and co-immunoprecipitation assays. Transmembrane neuregulins with each of the three known neuregulin cytoplasmic tail isoforms interacted with LIMK1. In contrast, the cytoplasmic tail of TGF-α did not interact with LIMK1. In vivo, neuregulin and LIMK1 are co-localized at the neuromuscular synapse, suggesting that LIMK1, like neuregulin, may play a role in synapse formation and maintenance. To our knowledge, LIMK1 is the first identified protein shown to interact with the cytoplasmic tail of a receptor tyrosine kinase ligand.
Prediction of cognitive decline based on hemispheric cortical surface maps of FDDNP PET

Abstract Objectives A cross-sectional study to establish whether a subject's cognitive state can be predicted based on regional values obtained from brain cortical maps of FDDNP Distribution Volume Ratio (DVR), which shows the pattern of beta amyloid and neurofibrillary binding, along with those of early summed FDDNP PET images (reflecting the pattern of perfusion) was performed. Methods Dynamic FDDNP PET studies were performed in a group of 23 subjects (8 control (NL), 8 Mild Cognitive Impairment (MCI) and 7 Alzheimer's Disease (AD) subjects). FDDNP DVR images were mapped to the MR derived hemispheric cortical surface map warped into a common space. A set of Regions of Interest (ROI) values of FDDNP DVR and early summed FDDNP PET (0–6 min post tracer injection), were thus calculated for each subject which along with the MMSE score were used to construct a linear mathematical model relating ROI values to MMSE. After the MMSE prediction models were developed, the models' predictive ability was tested in a non-overlapping set of 8 additional individuals, whose cognitive status was unknown to the investigators who constructed the predictive models. Results Among all possible subsets of ROIs, we found that the standard deviation of the predicted MMSE was 1.8 by using only DVR values from medial and lateral temporal and prefrontal regions plus the early summed FDDNP value in the posterior cingulate gyrus. The root mean square prediction error for the eight new subjects was 1.6. Conclusion FDDNP scans reflect progressive neuropathology accumulation and can potentially be used to predict the cognitive state of an individual.
On the relationship between finite volume and finite element methods applied to the Stokes equations

We investigate the relationship between finite volume and finite element approximations for the lower-order elements, both conforming and nonconforming for the Stokes equations. These elements include conforming, linear velocity-constant pressure on triangles, conforming bilinear velocity-constant pressure on rectangles and their macro-element versions, and nonconforming linear velocity-constant pressure on triangles and nonconforming rotated bilinear velocity-constant pressure on rectangles. By applying the relationship between the two methods, we obtain the convergence finite volume solutions for the Stokes equations. © 2001 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 17: 440–453, 2001.
Identification of a high affinity divalent cation binding site near the entrance of the NMDA receptor channel.

Abstract Single channel currents from recombinant N-methyl-D-aspartate (NMDA) receptors having an N-to-Q mutation in M2 reveal a divalent cation binding site that is near the entrance of the pore (∼0.2 through the electric field). Ca 2+ rapidly binds to this site and readily permeates the channel, while Mg 2+ binds more slowly and does not permeate as readily. In wild-type receptors, Mg 2+ also blocks the current by occupying a site that is ∼0.6 through the field. When the more external site is occupied by Ca 2+ , the conductance of the pore to Na + is reduced but not abolished, perhaps by an electrostatic blocking mechanism. The site serves to enrich the fraction of NMDA receptor current carried by Ca 2+ .
A Hierarchical Control Strategy For 2-D Object Recognition

A control strategy for 2-D object recognition has been implemented on a hardware configuration which includes a Symbolics Lisp Machine (TM) as a front-end processor to a 16,384 processor Connection Machine (TM). The goal of this ongoing research program is to develop an image analysis system as an aid to human image interpretation experts. Our efforts have concentrated on 2-D object recognition in aerial imagery specifically, the detection and identification of aircraft near the Danbury, CT airport. Image processing functions to label and extract image features are implemented on the Connection Machine for robust computation. A model matching function was also designed and implemented on the CM for object recognition. In this paper we report on the integration of these algorithms on the CM, with a hierarchical control strategy to focus and guide the object recognition task to particular objects and regions of interest in imagery. It will be shown that these tech-nigues may be used to manipulate imagery on the order of 2k x 2k pixels in near-real-time.
Mixing behavior of identical molecular weight phosphatidylcholines with various chain-length differences in two-component lamellae

It has recently been suggested that mixed-chain phosphatidylcholines with normalized chain length differences (deltaC/CL) in the range of 0.10–0.40 undergo spontaneous self-assembly in excess water at T less than Tm into the partially interdigitated bilayer and those with delta C/CL values in the range of 0.44–0.57 form, in excess water, mixed interdigitated bilayers at T less than Tm. The mixing behavior of binary mixtures of C(22):C(12)PC/C(17):C(17)PC, C(22):C(12)/C(15):C(19)PC, and C(15):C(19)PC/C(13):C(21)PC reported in this work is used to support this view. The values of delta C/CL for C(17):C(17)PC, C(15):C(19)PC, C(13):C(21)PC, and C(22):C(12)PC are 0.10, 0.15, 0.35, and 0.55, respectively. The binary mixture of C(15):C(19)PC/C(13):C(21)PC exhibits a lens-shaped phase diagram, indicating that these two identical molecular weight (MW) lipids with delta C/CL values less than 0.4 are completely miscible over the entire compositional range in both gel and liquid-crystalline phases. In contrast, the phase diagrams of C(22):C(12)PC/C(17):C(17)PC and C(22):C(12)PC/C(15):C(19)PC are eutectic, indicating immiscibility of the component lipids over a wide compositional range in the gel phase. This immiscibility of identical MW lipids in the bilayer plane can be attributed to the different packing properties of the component lipids in the bilayer at T less than Tm.
An investigation of a fluidized bed solids feeder for an aerosol flow reactor

Abstract Feeding a dispersed cloud of powder into an aerosol flow reactor, particularly on a laboratory scale, presents challenges. In this study, a fluid bed feeder was developed. With this feeder, fluidizing gas and brass milling media were the key means to disperse and break apart particle aggregates. Particle size distributions were measured with a laser imaging system and the dispersing ability of the feeder characterized by the result of statistical fits. Statistical results from a spinning wheel feeder, which uses primarily mechanical shear to disperse particles, was also compared with those from the fluid bed feeder to see which appeared to disperse powder the best. The results indicated that a fluidized bed feeder is likely a superior feeder to provide dispersed particles into a reactor. Additionally, the amount of mass fed versus time from the fluid bed feeder was measured under a variety of conditions. Two distinct mass feeding regions were observed and analyzed. Download : Download full-size image
Chaotic ionization of a Rydberg atom subjected to alternating kicks: Role of phase-space turnstiles

We study the ionization of a highly excited Rydberg atom subjected to a periodic sequence of external electric-field pulses. Such systems are important laboratory and theoretical models of classical and quantum chaos. Furthermore, a good theoretical understanding of this chaos is important for controlling electronic states in atoms, as has been demonstrated in a series of recent experiments on the creation and control of electronic wave packets. Here, we present a theoretical analysis of the chaotic ionization of a hydrogen atom subjected to alternating positive and negative impulses. This analysis is based on the observation that the ionization of the atom is due to a turnstile in phase space which promotes the electronic state from negative to positive energy. The geometry of the lobes associated with the turnstile provides a clear picture of how the ionization process proceeds. Using this geometric intuition, we propose two experimental protocols to directly reveal the importance of the turnstile lobes in the laboratory.
Kinetics and mechanism of BAL 31 nuclease action on small substrates and single-stranded DNA.

Abstract Kinetic and mechanistic aspects of the action of two forms of the BAL 31 nuclease (EC 3.1.11) from Alteromonas espejiana on model substrates, small oligonucleotides, larger oligonucleotides and poly[d(A)] have been examined. The minimal oligonucleotide substrate is a 5′-phosphorylated dinucleotide and a phosphodiester not containing a nucleotide residue is not cleaved. Both forms act predominantly in an exonucleolytic fashion on single-stranded DNA polymers in a highly processive manner; however, the mechanism becomes distributive for small oligomers (3–4 nucleotide residues). The direction of attack is from the 5′ end, in contrast to the mode of digestion of duplex DNA which involves attack at the 3′ termini. An endonucleolytic mode of attack also exists, but at a level 2–3% or less of that of the terminally directed cleavage. Apparent values for the catalytic efficiency of the action on long DNA polymers are too large to fit a simple kinetic scheme involving a direct enzyme-substrate encounter and lead to an interpretation in which nuclease molecules are non-productively bound away from the 5′ ends and undergo facilitated diffusion to yield productive (terminally bound) enzyme-substrate complexes.
Restoration of plant–pollinator interaction networks via species translocation

The recent decline in pollinator biodiversity, notably in the case of wild bee populations, puts both wild and agricultural ecosystems at risk of ecological community collapse. This has triggered calls for further study of these mutualistic communities in order to more effectively inform restoration of disturbed plant–pollinator communities. Here, we use a dynamic network model to test a variety of translocation strategies for restoring a community after it experiences the loss of some of its species. We consider the reintroduction of extirpated species, both immediately after the original loss and after the community has reequilibrated, as well as the introduction of other native species that were originally absent from the community. We find that reintroducing multiple highly interacting generalist species best restores species richness for lightly disturbed communities. However, for communities that experience significant losses in biodiversity, introducing generalist species that are not originally present in the community may most effectively restore species richness, although in these cases the resultant community often shares few species with the original community. We also demonstrate that the translocation of a single species has a minimal impact on both species richness and the frequency of community collapse. These results have important implications for restoration practices in the face of varying degrees of community perturbations, the refinement of which is crucial for community management.
Power source research at USC: Development of advanced electrocatalysts for polymer electrolyte membrane fuel cells

Abstract This paper provides an overview on the development of advanced fuel cell cathode catalysts at University of South Carolina (USC) with the emphasis on the stability of non-precious metal and Pt alloy catalysts. Nitrogen-modified carbon composite (NMCC) catalysts were developed for the oxygen reduction reaction (ORR) through the pyrolysis of cobalt (iron)–nitrogen chelate followed by the treatment combination of pyrolysis, acid leaching, and re-pyrolysis. A promising stability was observed for 1050 h fuel cell operation under current density of 200 mA cm −2 as evidenced by a potential decay rate as low as 40 μV h −1 . The performance degradation mechanism of the NMCC-based fuel cell is discussed. Pt and PtPd hybrid catalysts are developed that use a NMCC, which is itself active for the ORR, instead of a conventional carbon black support. The stability test at 1 A cm −2 indicated that the Pt/NMCC hybrid catalyst (new Pt–Co/C) is more stable than the conventional Pt–Co/C without the Co leaching out. The PEM fuel cell accelerated stress test (AST) for supports and catalysts demonstrated that their stability changes in the order: Pt 3 Pd 1 /NMCC hybrid catalyst > Pt/NMCC hybrid catalyst > conventional Pt/C catalyst. Moreover, the hybrid catalysts exhibit higher mass activity than the Pt/C catalysts.
Controlling the controls: GAD65 autoreactive T cells in type 1 diabetes

The clinical onset of autoimmune (type 1) diabetes is associated with multiple immune abnormalities. First, the islets of Langerhans are infiltrated with macrophages and CD4 and CD8 T lymphocytes. This islet inflammation, or insulitis, is related to a major loss of islet β cells. In addition, the onset is strongly associated with autoantibodies against specific islet cell autoantigens. In particular, autoantibodies against the smaller isoform of glutamic acid decarboxylase (GAD65), the islet antigen-2 (IA-2, also known as ICA512), or insulin are common at the day of clinical onset. The simultaneous presence of all three autoantibodies is highly predictive of type 1 diabetes (1).
Preparation and characterization of carbon-sulfur surface compounds

Abstract Carbon-sulfur surface compounds ( C χ S ), in which sulfur is chemically bound, have been prepared with a sulfur content greater than 30 wt.%. X-Ray diffractometry and electron microscopy show that the structure of the material is similar to that of disordered carbons. C χ S compounds are chemically stable in base and after an initial loss of several per cent of sulfur, they are stable in strong acids such as HCl and HNO 3 . In inert atmosphere, no measurable loss of sulfur was detected after being heated to 700°C. The XPS spectra (C 1s ,: 284.3 eV; S2p3/2: 163.7 eV) and the Fourier transform IR absorption spectra (1180,1550 cm −1 ) of CχS materials indicate no significant charge separation in carbon-sulfur bonds. Furthermore, these results suggest that, on CχS, carbon-sulfur surface groups exist in the form of thiocarbonyls, C and thiolactones, C, analogous to carbonyls and lactones existing on activated carbons.