cssi/SciSciGPT-SciSciNet huggingface dataset:
The Feeding Infants and Toddlers Study (FITS) 2016: Moving Forward.

The years from birth through preschool involve more changes in growth, development, eating patterns, nutrition, and other functions than any other time of life (1). Food consumption during this time is dynamic and is influenced by rapidly changing trends in feeding practices for infants and young children, as well as by longer-term trends in family incomes and food programs. It is critical to know what children are being fed, what they are eating, and how practices are changing, if we are to craft interventions that lay a solid nutritional foundation for later health, decrease risks of inappropriate eating habits, and develop evidence-based feeding recommendations. Informal guidelines for feeding the young have been available since antiquity. Today, we use formal evaluation of the evidence before making recommendations (2–5). Of particular relevance here is the Birth to 24 Months (B-24) project to evaluate data and support the addition of the first ever recommendations for children younger than 24 mo to the 2020–2025 Dietary Guidelines for Americans (6). Sound recommendations must be based on up-to-date information, and yet data on intakes and eating patterns are sparse, particularly for those <24 mo of age. NHANES provides much useful information for children <24 mo of age, but the sample sizes of both breast- and bottle-fed infants and toddlers are insufficient to trace the rapid changes in intakes that occur during that time (7, 8). The Feeding Infants and Toddlers Study (FITS) 2016 contributes to this evidence base and complements NHANES by applying similar methods to a large sample of infants and toddlers aged <24 mo, including minorities, providing greater detail about the adequacy of usual nutrient intakes and the foods and food groups consumed. FITS 2016 is a cross-sectional study of caregivers of children under the age of 4 y living in the 50 states and Washington DC. Data collection occurred between June 2015 and May 2016. A recruitment interview (respondent and child characteristics, feeding practices including responsive feeding and reasons for starting or stopping breastfeeding, physical activity, screen use, sleep habits, participation in food assistance programs) was completed by telephone or online. This was followed by a feeding practices questionnaire and a 24-h recall conducted by telephone. A second 24-h recall was collected for a random subsample of 25% of the total sampled population. Because FITS is a telephone survey, direct anthropometric data could not be collected; the lack of accurate anthropometric data or other biomarkers to link the food consumption data collected to health outcomes is a limitation (9).
Sex Differences on Vestibular and Ocular Motor Assessment in Youth Athletes

Context The Vestibular/Ocular Motor Screening (VOMS) is a newly developed measure that evaluates vestibular and ocular motor symptom provocation after sport-related concussion. The effects of sex o...
Postfire deciduous canopies drive patterns in snowshoe hare herbivory of regenerating black spruce

The future of boreal forests in Alaska, United States, will likely consist of more deciduous-dominant stands because larger and more severe fires facilitate the establishment of deciduous species s...
Structural verification of a tetrahydrotetrazole compound

Tetra­hydro­tetra­zoles are five-membered-ring heterocycles containing four contiguous saturated nitrogen atoms. Very few examples of such compounds have been reported in the literature. Our previous attempt at the synthesis of a member of this class of compound suggested that the N—N bonds may be more labile than expected. This finding raised the question as to whether the structures of any of the previously reported tetra­hydro­tetra­zoles had been properly assigned. We have reproduced the synthesis of a reported tetra­hydro­tetra­zole, namely 1,2-di-tert-butyl 3-phenyl-1H,2H,3H,10bH-[1,2,3,4]tetra­zolo[5,1-a]iso­quinoline-1,2-di­carboxyl­ate, C25H30N4O4, and have now confidently con­firmed its structure via X-ray crystallography. However, while sufficiently stable in the crystal phase, we discovered that it remains very labile in solution (having a half-life of only 15 min at 20 °C in CDCl3). A tentative reaction pathway for its dissociation based on 1H NMR spectral evidence is provided.
Tissue imaging depth limit of stimulated Raman scattering microscopy.

Stimulated Raman scattering (SRS) microscopy is a promising technique for studying tissue structure, physiology, and function. Similar to other nonlinear optical imaging techniques, SRS is severely limited in imaging depth due to the turbidity and heterogeneity of tissue, regardless of whether imaging in the transmissive or epi mode. While this challenge is well known, important imaging parameters (namely maximum imaging depth and imaging signal to noise ratio) have rarely been reported in the literature. It is also important to compare epi mode and transmissive mode imaging to determine the best geometry for many tissue imaging applications. In this manuscript we report the achievable signal sizes and imaging depths using a simultaneous epi/transmissive imaging approach in four different murine tissues; brain, lung, kidney, and liver. For all four cases we report maximum signal sizes, scattering lengths, and achievable imaging depths as a function of tissue type and sample thickness. We report that for murine brain samples thinner than 2 mm transmissive imaging provides better results, while samples 2 mm and thicker are best imaged with epi imaging. We also demonstrate the use of a CNN-based denoising algorithm to yield a 40 µm (24%) increase in achievable imaging depth.
Declined functional connectivity of white matter during rest and working memory tasks associates with cognitive impairments in schizophrenia

ABSTRACT BACKGROUND Schizophrenia, characterized by cognitive impairments, arises from a disturbance of brain network. Pathological changes in white matter (WM) have been indicated as playing a role in disturbing neural connectivity in schizophrenia. However, deficits of functional connectivity (FC) in individual WM bundles in schizophrenia have never been explored; neither have cognitive correlates with those deficits. METHODS Resting-state and spatial working memory task fMRI images were acquired on 67 healthy subjects and 84 patients with schizophrenia. The correlations in blood-oxygenation-level-dependent (BOLD) signals between 46 WM and 82 gray matter regions were quantified, analyzed and compared between groups under three scenarios (i.e., resting state, retention period and entire time of a spatial working memory task). Associations of FC in WM with cognitive assessment scores were evaluated for three scenarios. RESULTS FC deficits were significant (p CONCLUSIONS Decreases in FC are evident in several WM bundles in patients with schizophrenia and are significantly associated with cognitive impairments during both rest and working memory tasks. Furthermore, working memory tasks expose FC deficits in more WM bundles and more cognitive associates in schizophrenia than resting state does.
Psychometric Evaluation of the TIC Grade, a Self-Report Measure to Assess Youth Perceptions of the Quality of Trauma-Informed Care They Received:

BackgroundAgencies and clinical practices are beginning to provide trauma-informed care (TIC) to their clients. However, there are no measures to assess clients’ perceptions of and satisfaction wit...
Managerial discipline and corporate restructuring following performance declines

Abstract We examine the incidence of disciplinary events that reduce the control of current managers, and corporate restructuring among firms experiencing a large decline in operating performance during an active takeover period (1985–1988) and a less active period (1989–1992). We document a significant decline in the disciplinary events from the active to the less active period that is driven by a significant decline in disciplinary takeovers, those takeovers that result in a top executive change. Following the performance decline, however, there is a substantial amount of corporate restructuring, and a significant improvement in operating performance, during both the active and the less active takeover period. We conclude that, although some managerial disciplinary events are related to overall takeover activity, the decline in takeover activity does not result in fewer performance-enhancing restructurings following performance declines.
22 Developmental Control in Caulobacter crescentus: Strategies for Survival in Oligotrophic Environments

In stalked alphaproteobacteria such as Caulobacter crescentus, Asticcacaulis biprosthecum, and Hyphomicrobium neptunium, development is not triggered by environmental changes but is a consequence of normal progression through the cell cycle. In contrast to M. xanthus and B. subtilis, the oligotrophic C. crescentus has adopted a different strategy to cope with almost constant famine. First, the production of a chemotactically competent swarmer cell allows dispersal towards more nutritionally rich environments. Second, the successive synthesis of a flagellum, pili, and holdfast at the same pole of the cell optimizes attachment of swarmer cells to surfaces, thus improving the cell’s access to nutrients absorbed to surfaces. Finally, once attached tightly to a surface by its holdfast, the cell synthesizes a stalk, which dramatically improves nutrient uptake in the diffusion-limited environment where C. crescentus typically lives. This chapter focuses on the mechanisms of surface adhesion and stalk function, as well as how the overall developmental cycle is controlled. Differentiation is an essential process for adhesion of C. crescentus to surfaces. The stalk is an extension of the cell wall and membranes devoid of ribosomes, DNA, and cytoplasmic proteins. The stalk is transected perpendicularly by crossbands synthesized during each round of cell division, which may serve to compartmentalize the stalk from the cell body. A complex signal transduction pathway ensures that polar development, DNA replication, and cell division are coordinated. The new pole remains marked until late in cell division when TipN moves from the pole to the site of division.
Arterial ischemic perinatal stroke

Stroke is more common in the newborn period than at any other time in childhood and carries the risk of significant long-term neurodevelopmental morbidity. Arterial ischemic stroke may present acutely in the neonatal period, or may come to attention later when the child develops a hemiparesis or symptomatic epilepsy syndrome. Case-control and hospital-based cohort studies have revealed many factors associated with arterial ischemic perinatal stroke (IPS), including congenital heart disease, placental pathology, and thrombophilia. Since both motor and cognitive abnormalities may result, supportive care of the individual with arterial IPS requires a multidisciplinary approach and must extend beyond the acute illness phase. Herein we review the epidemiology, presentation, risk factors, suggested diagnostic approach, treatment, and outcomes of arterial IPS.
Enhancement of photonic density of states in finite graphene multilayers

We consider the optical properties of finite systems composed of a series of graphene sheets separated by thin dielectric layers. Because these systems respond as conductors to electric fields in the plane of the graphene sheets and as insulators to perpendicular electric fields, they can be expected to have properties similar to those of hyperbolic metamaterials. We show that under typical experimental conditions graphene/dielectric multilayers have enhanced Purcell factors, and enhanced photonic densities of states in both the terahertz (THz) and midinfrared (mid-IR) frequency range. These behaviors can be traced to the coupled plasmon modes of the multilayer graphene system. We show that these results can be obtained with just a few layers of graphene.
Philosophical Reflection on Petitionary Prayer

If God actually answers prayers that petition him for something, then it seems he is willing to withhold some good(s) from the world unless and until someone prays for those goods. But how is this compatible with His benevolence? On the other hand, if God is dedicated to providing every good to us that we may need, it would seem that He would provide these to us even if we did not pray for them. But if so, it would appear that petitionary prayer is pointless. This discussion reviews the various contributions (especially the most recent ones) made by philosophers in trying to answer these questions, and in criticizing these answers.
Degeneration of cochlear neurons as seen in the spiral ganglion of man

A light and electron microscopic study of the spiral ganglion cells of a normal individual, a patient with Meniere's syndrome, and a patient with long-standing unilateral profound deafness was done to evaluate patterns of neural degeneration in the human inner ear. Parametric data for the normal spiral ganglion are presented and compared with the pathologic ganglia. In the ear with Meniere's syndrome, the nuclear area and axonic diameter of spiral ganglion cells were significantly smaller than in the contralateral and the normal ear. This was interpreted as evidence of neuronal degeneration in Meniere's syndrome. In the spiral ganglion of the long-standing deaf ear, there appeared to be selective preservation of large cells with no dendritic processes, contrary to the pattern of degeneration seen in the spiral ganglion of the animal.
Representations of group planar algebras

Abstract We explicitly find out the irreducible representations of the planar algebra corresponding to the subfactor arising from the action of a finite group. We also answer the question posed by Vaughan Jones on the radius of convergence of the dimension of a representation in the affirmative for the case of group planar algebras.
Theory and Practice of Teaching for Transfer.

Transfer of teaching is central to education. In this article, the evolution of the sole viable theory of transfer—the theory of common elements—is traced from its mentalistic beginnings, through the behaviorist view of elements as stimuli and responses related by the mechanism of conditioning, to the contemporary view of elements as mental representations, knowledge, and strategies operated on by cognitive mechanisms including automatization, inferential reasoning, and metacognitive monitoring. Second, the cognitive theory of elements and mechanisms is used to answer three educationally crucial questions: (1) How do students select, from all they have learned, particular knowledge and skills for use in new situations? (2) What determines the utility of the knowledge and skills selected? (3) When selected knowledge and skills are not useful, what determines whether and how learners cope? Third, the authors identify what they view as needed refinements in experimental methods of studying transfer, in the theory of common elements, in basic and applied research, and in the uses of technology in education.
Coping with serious illness on integrating constructs to enhance clinical research assessment and intervention

Empirical research suggests that given relatively similar illness contingencies, patients who cope successfully with serious illness have access to and use effectively social network support, believe events are to some extent within their control, perceive themselves to be effective, and employ an array of flexible coping strategies. Based on a selective literature review, the argument is made that more integrative conceptual frameworks are needed to advance theory and to enhance the applied value of research data. Clinical implications for assessment, intervention, and evaluation are set forth.
Quantitative determination of Ascaris eggs in clear suspensions by photonephelometry

Abstract Clear suspensions of Ascaris lumbricoides var. suis eggs in different concentrations were estimated by nephelometric readings and the results were compared with dilution egg counts. A linear relationship between the concentration factors and the nephelometric readings was observed. Under the present experimental conditions, each nephelometric unit was equivalent to approximately 65 eggs per milliliter. Statistical analysis of the data revealed that the variability between different readings was directly proportional to the magnitude of egg concentrations. The nephelometric determinations yielded substantially smaller variabilities and required considerably less time to perform than the dilution egg counts.
The use of dimensionless groups in electrochemistry

Abstract The applications of dimensional analysis and dimensionless groups in electrochemical mass transfer problems are discussed. On the basis of this review suggestions for the definition of some quantities pertaining to electrochemical mass transfer are made in connection with the work of the CITCE commission for electrochemical nomenclature and definitions.
A Novel, One-Pot Reductive Alkylation of Amines by S-Ethyl Thioesters Mediated by Triethylsilane and Sodium Triacetoxyborohydride in the Presence of Palladium on Carbon.

The reductive alkylation of primary amines with aldehydes or ketones is an important tool in the synthesis of wide variety of amines. We described here a novel, one-pot reductive alkylation method using multifunctional S-ethyl thioesters as a source for in situ generation of aldehydes to alkylate a range of multifunctional primary amines. The corresponding multifunctional secondary amines were obtained in good to excellent yields (mostly >90%). This one-pot reductive alkylation included the treatment of a mixture of protected S-ethyl thioester, primary amine, 10% Pd/C, and sodium triacetoxyborohydride in N,N-dimethylformamide with triethylsilane for 30 min at temperature lower than 20 °C. This method has special merit when the aldehyde is not stable enough to allow isolation and therefore does not lend itself to a stepwise strategy of reductive alkylation. This was the case with tert-butyl 1(S)-[(9-fluorenylmethoxycarbonyl)amino]-4-oxobutyrate (10) which could not be obtained from the α-tert-butyl γ-S-eth...
General manager perceptions of guest satisfaction measurement systems in the hotel industry.

ABSTRACT This research examined 151 hotel general managers' perceptions of four different guest satisfaction measurement systems in the hotel industry. The results found that general managers had questionable confidence in the output from any of the systems investigated. The general managers felt that all systems present sample size, representative sample and manipulation problems. The general managers had the greatest confidence in third-party mail-out satisfaction systems and preferred these systems in a rank-order response.
Redressing the balance of community schooling and religion in the USA 1

The varying definitions and conceptions of secularism are explored in terms of government interpretation and legal response. It is argued that issues of state neutrality towards religion can be balanced with religious expression within the context of community schooling in the USA. Examining a more balanced approach of effects of government action or inaction as it pertains to the Establishment Clause can help create a clearer understanding of the proper philosophical and legal place of religious expression within the public spaces of government schooling.
Prenatal Treatment of Biotin‐responsive Multiple Carboxylase Deficiency

The prenatal diagnosis and prenatal treatment of a fetus with the neonatal-onset variant of biotin-responsive multiple carboxylase deficiency are described. Pre-amniocentesis maternal urinary organic-acid profiles were normal. Amniotic-fluid methylcitrate (17 weeks' gestation) was ten standard deviations above the control mean. Amniotic-fluid-cell propionyl CoA carboxylase, pyruvate carboxylase, and 3-methylcrotonyl CoA carboxylase activities were indistinguishable from activities in controls after cell growth in biotin-supplemented media. In contrast, growth in biotin-restricted media resulted in carboxylase activities significantly below control values. The fetus was considered to be affected, and the mother was begun on oral biotin at 231/2 weeks' gestation. The full-term baby girl exhibited no clinical or chemical aberrations during the first 4 days of life, before the start of postnatal biotin supplementation. Cord-blood biotin was 34 times the upper normal neonatal concentration. The diagnosis was confirmed by carboxylase assays on cultured skin fibroblasts obtained after birth; by slightly raised urinary organic-acid levels later in infancy; and by demonstration of· fibroblast holocarboxylase synthetase with an elevated Km(biotin) and a depressed Vmax. Growth and development of the baby have been normal to age 11/4 years on oral biotin. The prenatal diagnosis of neonatal-onset biotin-responsive multiple carboxylase deficiency can be made by means of enzymatic studies of amniotic-fluid cells. Amniotic-fluid methylcitrate should be a useful adjunct to enzymatic studies. Prenatal treatment was effective in our patient, and there was no apparent toxicity to mother or baby from biotin supplementation during the last 16 weeks of pregnancy.
Membrane-mediated extractive fermentation for lactic acid production from cellulosic biomass.

Lactic acid production from cellulosic biomass by cellulase and Lactobacillus delbrueckii was studied in a fermenter-extractor employing a microporous hollow fiber membrane (MHF). This bioreactor system was operated under a fed-batch mode with continuous removal of lactic acid by an in situ extraction. A tertiary amine (Alamine 336) was used as an extractant for lactic acid. The extraction capacity of Alamine 336 is greatly enhanced by addition of alcohol. Long-chain alcohols serve well for this purpose since they are less toxic to micro-organism. Addition of kerosene, a diluent, was necessary to reduce the solvent viscosity. A solvent mixture of 20% Alamine 336, 40% oleyl alcohol, and 40% kerosene was found to be most effective in the extraction of lactic acid. Progressive change of pH from an initial value of 5.0 down to 4.3 has significantly improved the overall performance of the simultaneous saccharification and extractive fermentation over that of constant pH operation. The change of pH was applied to promote cell growth in the early phase, and extraction in the latter phase.
pNFS, POSIX, and MPI-IO: a tale of three semantics

MPI-IO is emerging as the standard mechanism for file I/O within HPC applications. While pNFS demonstrates high-performance I/O for bulk data transfers, its performance and scalability with MPI-IO is unproven. To attain success, the consistency semantics and interfaces of pNFS, POSIX, and MPI-IO must all be reconciled and efficiently translated. This paper investigates and discusses the challenges of using pNFS to support the consistency semantics of HPC applications.
Pressurized Hot Water Procedures for Use on Small Farms in Developing Countries

Abstract Soil analysis for small farms in developing countries is often inconvenient and prohibitively expensive, yet the information gained from these soil tests could result in significant benefits. Based on tests done on a limited range of soils, the pressurized hot water (PHW) extraction coupled with colorimetric or turbidimetric analysis is a promising alternative. Before this extraction and analysis can be used in developing countries, testing is needed across the range of soils found in these countries. At Brigham Young University (BYU), 228 soils from Guatemala and Morocco were analyzed for NO3‐N, phosphorus (P), and potassium (K) using standard methods (water–CTA, Olsen–molybdic acid and ammonium acetate–atomic absorption, respectively). Results were correlated to values obtained from the PHW extraction coupled with colorimetric or turbidimetric analytical procedures. The relationships between these tests were good (r2 values of 0.96, 0.71, and 0.52 for NO3‐N, P, and K, respectively). In an addit...
The utility of positron emission tomography in staging of potentially operable carcinoma of the thoracic esophagus: Results of the American College of Surgeons Oncology Group Z0060 trial

Objectives The American College of Surgeons Oncology Group trial Z0060 is a prospective multi-institutional trial with a primary objective to evaluate whether positron emission tomography (PET) with F-18 fluorodeoxyglucose (FDG) detects evidence of metastastic disease that precludes esophagectomy in patients with esophageal cancer who are surgical candidates after routine staging. Methods Patients with resectable, biopsy-proven carcinoma were enrolled after computed tomography of chest and abdomen demonstrated no evidence of metastasis. FDG-PET was performed according to specified standards. FDG-PET findings suggesting metastases required confirmation and patients without metastases on PET were expected to proceed to surgery. Results A total of 262 patients were registered. Of these, 199 were deemed eligible and of these, 189 patients were evaluable. Seventy-three patients were ineligible or unevaluable. Reasons for ineligibility included nonresectable disease by routine staging (39), missing or outdated staging procedures (12), PET technical protocol violations (10), no cancer (4), pre-PET induction therapy (3), claustrophobia (1), and other causes (4). There were 145 (78%) patients who went on to have surgery, 42 (22%) who did not, and 2 patients for whom the surgical status was not determined. The reasons for no resection included the following: M1 disease found by PET and confirmed (9), M1 disease found by PET and not confirmed (2), M1 disease at exploration not found by PET (7), decline or death before surgery (10), patient refusal of surgery (7), unresectable local tumor at exploration (5), and extensive N1 disease precluding operation (2). Eight (4.2%) patients undergoing resection had a recurrence in the first 6 months. Conclusions Although 22% of eligible patients did not undergo esophagectomy, FDG-PET after standard clinical staging for esophageal carcinoma identified confirmed M1b disease in at least 4.8% (95% confidence interval: 2.2%-8.9%) of patients before resection. Unconfirmed PET evidence of M1 disease and regional adenopathy (N1 disease) led to definitive nonsurgical or induction therapy in additional patients.
Death rates among California's foster care and former foster care populations

Abstract Crude death rates are computed for 690 children who died while in foster care in California during 1988 to 1994. These death rates are compared to those for the general population of children in California, as well as for 321 former foster care children who were in care during the same time period and died after being released (and prior to age 19). While death rates of children in foster care during the study period were generally higher than those for the general population during the same period, breakdowns by age, race/ethnicity, cause of death, and type of care reveal important exceptions. Caucasian and Hispanic children in foster care have higher rates of death than their counterparts in the general population, whereas African American foster children experience comparable rates relative to African American children in the general population. Postneonates in foster care have higher rates of death relative to postneonates in the general population. Foster care children aged 1 through 9 years have higher rates of death regardless of race/ethnicity, while older children aged 10 through 18 have comparable rates of death relative to non-foster children. Regarding cause of death, foster children experience higher mortality rates (relative to the general population) due to natural causes, “ill-defined conditions” and SIDS, and violent deaths, while former foster children experience high rates of death from violent causes. African Americans in foster care have lower rates of death from preventable causes, while Hispanic and Caucasian children have comparable rates of death for these causes compared with the general population. Lastly, both current and former foster children entering care for reasons of neglect have higher mortality rates than the general population of children for preventable, congenital/perinatal, and natural deaths. Interpretation of the findings is complicated because children in foster care constitute a more fragile and impoverished population than the general population of children.
Separation and reattachment of non-newtonian fluid flows in a sudden expansion pipe

Abstract In the current flow visualization studies, the role of non-Newtonian characteristics (such as shear-rate-dependent viscosity and viscoelasticity) on flow behavior across the sudden expansion step in a circular pipe is investigated over a wide range of Reynolds numbers including the turbulent flow. The expansion ratios tested are 2.000 and 2.667 and the range of the Reynolds number covered in the current flow visualization tests are 10–35 000 based on the inlet diameter. The reattachment lengths for the viscoelastic fluids in the laminar flow regime are found to be much shorter than those for the Newtonian fluid. In addition they decrease significantly with increasingly concentration of viscoelastic fluid at the same Reynolds number. However, in the turbulent flow regime, the reattachment length for the viscoelastic fluids is two or three times longer than those for water, and gradually increases with increasing concentration of viscoelastic solutions, resulting in 25 and 28 step-height distances for 500 ppm and 1000 ppm polyacrylamide solutions respectively. This may be because the elasticity in polyacrylamide solutions suppresses the eddy motion and controls separation and reattachment behavior in the sudden expansion pipe flow. The reattachment lengths for the purely viscous non-Newtonian fluids are found to be almost the same as those for water.
The Affinity Grid: A Pre-fabricated EM Grid for Monolayer Purification

We have recently developed monolayer purification as a rapid and convenient technique to produce specimens of His-tagged proteins or macromolecular complexes for single-particle electron microscopy (EM) without biochemical purification. Here, we introduce the Affinity Grid, a pre-fabricated EM grid featuring a dried lipid monolayer that contains Ni-NTA lipids (lipids functionalized with a nickel-nitrilotriacetic acid group). The Affinity Grid, which can be stored for several months under ambient conditions, further simplifies and extends the use of monolayer purification. After characterizing the Affinity Grid, we used it to isolate, within minutes, ribosomal complexes from Escherichia coli cell extracts containing His-tagged rpl3, the human homolog of the E. coli 50 S subunit rplC. Ribosomal complexes with or without associated mRNA could be prepared depending on the way the sample was applied to the Affinity Grid . Vitrified Affinity Grid specimens could be used to calculate three-dimensional reconstructions of the 50 S ribosomal subunit as well as the 70 S ribosome and 30 S ribosomal subunit from images of the same sample. We established that Affinity Grids are stable for some time in the presence of glycerol and detergents, which allowed us to isolate His-tagged aquaporin-9 (AQP9) from detergent-solubilized membrane fractions of Sf9 insect cells. The Affinity Grid can thus be used to prepare single-particle EM specimens of soluble complexes and membrane proteins.
A high-speed network interface for distributed-memory systems: architecture and applications

Distributed-memory systems have traditionally had great difficulty performing network I/O at rates proportional to their computational power. The problem is that the network interface has to support network I/O for a supercomputer, using computational and memory bandwidth resources similar to those of a workstation. As a result, the network interface becomes a bottleneck. In this article we present an I/O architecture that addresses these problems and supports high-speed network I/O on distributed-memory systems. The key to good performance is to partition the work appropriately between the system and the network interface. Some communication tasks are performed on the distributed-memory parallel system, since it is more powerful and less likely to become a bottleneck than the network interface. Tasks that do not parallelize well are performed on the network interface, and hardware support is provided for the most time-critical operations. This architecture has been implemented for the iWarp distributed-memory system and has been used by a number of applications. We describe this implementaiton, present performance results, and use application examples to validated the main features of the I/O architecture.
A survey of general-purpose manipulation

A general-purpose manipulator, in conjunction with other sensory modalities, can be used to measure the three-dimen sional character of the environment, support object recogni tion and localization procedures, and perform alternately as a delicate and powerful manipulator. This paper surveys the technologies which support general-purpose manipulation. While machines are capable of outperforming the human hand in specific applications, there is no machine capable of addressing the variety of tasks accomplished by our hands. We begin, therefore, by discussing the human hand. Some of the "bioware" supporting manipulation and haptics in humans is described. The development of hardware to sup port general-purpose manipulation is progressing rapidly. We focus on tactile sensing techniques and their role in percep tion. A variety of mechanical manipulators used in research and the methods employed to control them are presented. Finally, we discuss properties of the task, the manipulator, and the object which con...
CHOICE, DELAY, PROBABILITY, AND CONDITIONED REINFORCEMENT

The hyperbolic-decay model is a mathematical expression of the relation between delay and reinforcer value. The model has been used to predict choices in discrete-trial experiments on delay-amount tradeoffs, on preference for variable over fixed delays, and on probabilistic reinforcement. Experiments manipulating the presence or absence of conditioned reinforcers on trials that end without primary reinforcement have provided evidence that the hyperbolic-decay model actually predicts the strength of conditioned reinforcers rather than the strength of delayed primary reinforcers. The model states that the strength of a conditioned reinforcer is inversely related to the time spent in its presence before a primary reinforcer is delivered. A possible way to integrate the model with Grace’s (1994) contextual-choice model for concurrent-chain schedules is presented. Also discussed are unresolved difficulties in determining exactly when a stimulus will or will not serve as a conditioned reinforcer.
Continual Reassessment Method vs. Traditional Empirically-Based Design: Modifications Motivated by Phase I Trials in Pediatric Oncology by the Pediatric Brain Tumor Consortium

In this article we provide additional support for the use of a model-based design in pediatric Phase I trials and present our modifications to the continual reassessment method (CRM), which were largely motivated by specific challenges we encountered in the context of the Pediatric Brain Tumor Consortium trials. We also summarize the results of our extensive simulations studying the operating characteristics of our modified approach and contrasting it to the empirically based traditional method (TM). Compared to the TM, our simulations indicate that the modified version of CRM is more accurate, exposes fewer patients to potentially toxic doses, and tends to require fewer patients. Further, the CRM-based MTD has a consistent definition across trials, which is important, especially in a consortium setting where multiple agents are being tested in studies that are often running simultaneously and accruing from the same patient population.
A review of microstructure in concentrated suspensions and its implications for rheology and bulk flow

An overview of present understanding of microstructure in flowing suspensions is provided. An emphasis is placed on how the microstructure leads to observable bulk flow phenomena unique to mixtures. The bridge between the particle and bulk scales is provided by the mixture rheology; one focus of the review is on work that addresses the connection between microstructure and rheology. The non-Newtonian rheology of suspensions includes the well-known rate dependences of shear thinning and thickening, which have influence on bulk processing of suspensions. Shear-induced normal stresses are also measured in concentrated suspensions and include normal stress differences, and the isotropic particle pressure. Normal stresses have been associated with shear-induced migration, and thus have influence on the ultimate spatial distribution of solids, as well as the flow rate during processing; a second focus is on these uniquely two-phase behaviors and how they can be described in terms of the bulk rheology. An important bulk fluid mechanical consequence of normal stresses is their role in driving secondary flows.
One step Pd(0)-catalyzed synthesis, X-ray analysis, and photophysical properties of cyclopent[hi]aceanthrylene: fullerene-like properties in a nonalternant cyclopentafused aromatic hydrocarbon.

A simple procedure for the synthesis of cyclopentafused polycyclic aromatic hydrocarbons (CP-PAH) with Pd(PPh3)2Cl2 catalyst has been applied to the one-pot palladium(0)-catalyzed coupling of 9,10-dibromoanthracene (1) with 2-methyl-3-butyn-2-ol. Reactions carried out in refluxing benzene in the presence of CuSO4/Al2O3 yielded 9,10-dialkynylanthracene 2a, alkynyl aceanthrylene 2b, and 2,7-disubstituted cyclopent[hi]aceanthrylene 2c in 13%, 23%, and 19% purified yields, respectively, with total conversions of 80−90%. Sealed tube reactions without copper at 110 °C improved the yield of 2c up to >75%. Single-crystal X-ray analyses of 2a and 2c reveal a three-dimensional hydrogen bonding network, producing a unique crystal packing. The packing structure of 2b is dominated by π−π stacking interactions between two aceanthrylene molecules. CP-PAHs 2b and 2c have potentially interesting fullerene-like photophysics. While the UV−vis and fluorescence spectra of 2a (ΦF = 0.87) show the characteristic vibronic struct...
Changes in word production, sentence production and relevance in an aphasic through verbal conditioning

Abstract Verbal conditioning techniques were introduced over 98 sessions dealing with several response dimensions of an aphasic patient. Verbal, token, and self-reinforcement and punishment, delayed feedback and modeling were systematically employed. Increases resulted in frequency of words, sentences, and relevant utterances. Decreases were produced in unclear, perseverative, and irrelevant utterances. This study suggests that several characteristic deficit areas in an aphasic might be dealt with by means of verbal conditioning technology. The most marked changes appeared to occur as a result of modeling, self-punishment, and delayed reinforcement.
Comparative clearance of quartz and cristobalite from the lung

The two silicon dioxide polymorphs, quartz and cristobalite, are known to have different toxicities. The clearance kinetics and biological response of two sources of quartz and one source of Pule cristobalite were compared. Models were also developed to show the accumulation of cristobalite in the lungs of Fischer 344 rats as the result of short-term exposures at three different concentrations. The amount of cristobalite cleared from the lung was considerably less than that of the two quartz materials, with little or no clearance after the initial 30 days post exposure. As an indicator of the cellular biological response to the aerosols, total and differential cell counts were measured on bronchoalveolar lavage specimens. Cristobalite showed an early and sustained response with an elevated macrophage, neutrophil, and lymphocyte count through 180 days post exposure. The two quartz Materials were not identical in their biological behavior even though they had identical crystal structure and similar trace el...
Effects of spacing of item repetitions in continuous recognition memory: does item retrieval difficulty promote item retention in older adults?

Background/Study Context: Older adults exhibit an age-related deficit in item memory as a function of the length of the retention interval, but older adults and young adults usually show roughly equivalent benefits due to the spacing of item repetitions in continuous memory tasks. The current experiment investigates the seemingly paradoxical effects of retention interval and spacing in young and older adults using a continuous recognition memory procedure. Methods: Fifty young adults and 52 older adults gave memory confidence ratings to words that were presented once (P1), twice (P2), or three times (P3), and the effects of the lag length and retention interval were assessed at P2 and at P3, respectively. Results: Response times at P2 were disproportionately longer for older adults than for younger adults as a function of the number of items occurring between P1 and P2, suggestive of age-related loss in item memory. Ratings of confidence in memory responses revealed that older adults remembered fewer item...
The independence of the parallel postulate and development of rigorous consistency proofs

I trace the development of arguments for the consistency of non-Euclidean geometries and for the independence of the parallel postulate, showing how the arguments become more rigorous as a formal conception of geometry is introduced. I analyse the kinds of arguments offered by Jules Houel in 1860–1870 for the unprovability of the parallel postulate and for the existence of non-Euclidean geometries, especially his reaction to the publication of Beltrami's seminal papers, showing that Beltrami was much more concerned with the existence of non-Euclidean objects than he was with the formal consistency of non-Euclidean geometries. The final step towards rigorous consistency proofs is taken in the 1880s by Henri Poincare. It is the formal conception of geometry, stripping the geometric primitive terms of their usual meanings, that allows the introduction of a modern fully rigorous consistency proof.
Pathogenic and nef-interrupted simian-human immunodeficiency viruses traffic to the macaque CNS and cause astrocytosis early after inoculation.

Abstract Several studies have shown that deletion of the nef gene of simian immunodeficiency virus (SIV) and simian–human immunodeficiency virus (SHIV) results in attenuated viruses. However, studies have not critically examined trafficking of attenuated viruses to the central nervous system (CNS) at early stages after inoculation. In this study, we investigated the colocalization of pathogenic and vpu -negative, nef -interrupted SHIVs at early stages following inoculation. The first virus, designated SHIV 50OLNV , was isolated from the lymph node of a pig-tailed macaque which developed severe CD4 + T cell loss and neurological disease. The second virus was a molecularly cloned virus in which the vpu gene was deleted and the gene for the enhanced green fluorescent protein from the jellyfish Aequoria victora had been inserted in-frame within the nef gene of the pathogenic SHIV KU-1bMC33 (designated SHIV KU-1bEGFP ). Three pig-tailed macaques were inoculated intravenously with equivalent amounts of two viruses, two macaques were inoculated with SHIV KU-1bEGFP , and two macaques were inoculated with SHIV 50OLNV . The peripheral blood mononuclear cells (PBMCs) were isolated from bleeds obtained 3, 7, 10, and 14 days postinoculation and monitored for syncytia-inducing virus and for fluorescent cells. Virus was detected in the PBMCs as early as 3 days postinoculation and was present throughout the course of this short-term study. At 14 days postinoculation, the macaques were sacrificed and examined for virus in lymphoid tissues and different regions of the CNS following necropsy. Our results revealed the presence of both viruses in lymphoid and CNS tissues, although SHIV 50OLNV was present to a much greater extent. Histological examination revealed that one macaque displayed signs of meningitis and all three macaques developed massive cortical astrocyte activation as demonstrated by immunostaining for glial fibrillary acidic protein, but only limited microglial activation. In the two macaques inoculated with SHIV 50OLNV , astrocyte activation similar to that in the macaques inoculated with both viruses was observed while no astrocyte activation was observed in macaques inoculated with SHIV KU-1bEGFP . Thus, this study demonstrates that SHIVs with an intact nef (SHIV 50OLNV ) as well as those lacking a vpu gene and with a nonfunctional nef gene (SHIV KU-1bEGFP ) are capable of invading the CNS and that pathogenic SHIVs are capable of causing reactive astrocytosis early after inoculation.
Cirrus-cloud thermostat for tropical sea surface temperatures tested using satellite data

Cirrus clouds associated with tropical convection may shield the ocean from sunlight and therefore act as a thermostat to limit tropical SST (sea surface temperature) to less than 305 K. This hypothesis was tested using satellite radiance data. It was found that changes in the properties of cirrus clouds do not seem to be related to changes in SSTs. During the 1987 El Nino event large-scale atmospheric circulation changes rather than the direct effect of SSTs seemed to control large-scale changes in radiative effects of cirrus clouds. If averaged over the entire tropical Pacific, increases in surface evaporative cooling are stronger than decreases in solar heating owing to cirrus cloud variation. This would indicate that there is no cirrus cloud thermostat to tropical SSTs.
Ultraviolet Light-induced Formation of Pisatin and Phenylalanine Ammonia Lyase.

The production of pisatin is induced3 in pea tissue by various plant pathogens (4, 8). This de novo synthesis can also be induced by an array of chemicals (9, 19, 22), most of which are known to have an affinity for double stranded DNA. Also, most of the inducers of pisatin or phenylalanine ammonia lyase (PAL)', EC 4.3.1.5 (a key enzyme in the biosynthesis of pisatin) have the potential to change the conformation of DNA. The induction of both pisatin and PAL is dependent on new RNA and protein synthesis (9, 22). We have proposed (9, 22) that the control of these cellular responses occurs at the gene transcription level and depends on the conformational state of the double stranded DNA (i.e., the DNA becomes more transcribable either by dissociating a repressor component or by assuming a more desirable conformation for transcription). If conformational changes in cellular DNA do, in fact, initiate this response, ultraviolet light which can dimerize thymidine bases and cause lesions in DNA (5, 23) should also influence this response. This paper describes the induced synthesis of pisatin and PAL by ultraviolet light.
Soil characterization for indoor radon potential at eighteen schools in New York State

During the two school years between 1991 and 1993, 60 schools were measured for indoor radon in New York State. Schools were solicited from areas considered to be at risk for above-average indoor radon based on residential indoor radon measurements and on the geology of the area. Eighteen of the sixty schools participating in the New York State study were selected for soil-radon potential characterization. Soils near the perimeter of the school, in the school yard, and in crawl spaces were measured for soil 226Ra concentration, soil-gas 222Rn concentration, and permeability for gas flow. In general, above-average indoor radon concentrations in the schools were found to correlate with highly permeable, gravelly soils. At 10 schools, the average soil permeability for gas flow was greater than 3 × 10−10m2 for each school, and 47% of the rooms tested in these 10 schools had long-term indoor radon concentrations greater than 150 Bq/m3. The soils near the 10 schools were generally glacial outwash gravel deposits containing average concentrations of 226Ra and soil-gas 222Rn.