cssi/SciSciGPT-SciSciNet huggingface dataset:
Brittle crack initiation at the elastic-plastic interface

To study fracture initiation near notches experiments were conducted on polycarbonate at room temperature. It could be demonstrated conclusively that cracks are nucleated under the influence of a critical normal stress at the elastic-plastic boundary. Slip line field theory allows the determination of the critical normal fracture stress from the knowledge of the notch root radius and the location of the crack nucleation. For 0.5 in. thick specimens with root radii between 0.001 and 0.01 in. the calculated critical fracture stress of polycarbonate is nearly constant, 21.2 ±0.6 ksi. An analysis of the data in accordance with the theory developed by R. Beeuwkes, Jr. for parabolic notches resulted in critical fracture stress values of approximately 21.5 ksi. Specimens with central holes between 0.04 and 0.05 in. diam also showed crack nucleation below the surface of the hole but the calculated critical fracture stress values were considerably lower, approximately 11.2 ksi. This may be attributed to the loss of plane strain conditions in these 0.5 in. thick specimens. The experimentally observed slip lines in polycarbonate are not orthogonal to each other but intersect at a lower (~80 deg) angle. This may be due to the relief of stresses on unloading and sectioning, and it may indicate that plane strain conditions were not present. Because of its flow characteristics, which are similar to those of metals, and because of its transparency, polycarbonate appears to be a good model material for the study of plastic flow initiated brittle fracture. It could be used to check the theoretical slip line field solutions proposed for a variety of loading conditions.
A study of the ventricular gradient in normal infants and children.

Abstract 1. 1. The electrocardiograms of 172 infants and children without heart disease and ranging in age from a few hours to sixteen years were analyzed for ÂQRS, ÂT and Ĝ in the frontal plane projection. 2. 2. The mean ÂQRS and Ĝ were of less magnitude during the first three years of life than in adults. During the first year of life ÂQRS was directed more to the right than in adults. 3. 3. Except for five subjects, the angles between Ĝ and ÂQRS, and Ĝ and ÂT were less than 30 degrees. 4. 4. It is concluded that the mean ÂQRS, ÂT and Ĝ for children are very similar to adults except for the differences noted before the third year of life, and that the standards that already exist in the literature for adults are applicable to children.
Lunar Excavation Experiments in Simulant Soil Test Beds: Revisiting the Surveyor Geotechnical Data

AbstractThe establishment of permanent bases on planetary surfaces is an important long-term goal of the space community. Understanding the geotechnical properties of planetary surfaces and their interaction with tools and implements will be essential in addressing the challenges of material-handling equipment for infrastructure development during surface missions. With this aim, a replica of the soil mechanics surface sampler, an extendable scoop with a bearing plate attachment, operated on some of the lunar Surveyor missions in the 1960s, was fabricated and used in a series of simulated bearing and excavation tests. Initially, a set of tests was performed on a small laboratory test stand using an acrylic soil bin with a 30.5×33.0-cm footprint. Subsequent tests were performed in a new large-scale soil bin facility (2.27×5.94×0.76 m) to minimize wall effects. Both test setups involved the use of JSC-1a lunar simulant soil beds and motorized actuators to drive the scoop into the simulant. Emphasis was plac...
Excretion of Uric Acid in Periplaneta americana

Srivastava and Gupta (1961) postulated that the malpighian tubules in the American cockroach do not function in the removal of uric acid. However, the silver method of Gomori (1952) for uric acid shows typical staining in the tubules, and especially dense staining at the junction of the tubules and the gut (Fig. 1).
A thick composite-beam model for delamination prediction by the use of neural networks

A composite beam with a delamination has been modeled, accounting for the Poisson effect and transverse shear deformation. Delaminations may be caused by imperfections introduced during the fabrication process or by external loads during the operational life, such as impact by foreign objects. A consequence of delamination is the change in stiffness of the structure, and this affects the modal frequencies of the structure. The applicability of neural networks in determining delaminations in laminated composite beams is examined in the present study. The modal frequencies are obtained by using the beam model for different delamination sizes and locations. The beam model developed is applicable to various boundary conditions. A back-propagation neural network is trained to predict the delamination size and location from the natural frequencies of the beam. The neural-network model is found to be quite successful in determining the delamination size and location.
History of Stage 5 Sea Level in Bermuda: Review with New Evidence of a Brief Rise to Present Sea Level During Substage 5a

Abstract Oxygen-isotope Substage 5e is represented by the Devonshire Formation in Bermuda. The occurrence of these coastal-marine deposits to about 5 m indicates Pleistocene sea-level data in Bermuda do not need tectonic corrections. A few published U-series coral dates suggest that a conglomerate (Spencer's Point Formation) may have formed during Substage 5c. Geologic mapping, however, indicates that the eolianite beneath the conglomerate is pre- rather than post-Devonshire Formation in age as was previously thought, and the aminostratigraphy of marine sheels also confirms the correlation of the Spencer's Point and Devonshire Formations. Substages 5c and 5a are represented by the Southampton Formation. Large eolianites comprise the bulk of this formation. They are onlapped by a few, small, younger marine (+1 m) and eolian deposits. Aminostratigraphy confirms that these late Southampton age deposits are significantly younger than the Devonshire Formation, and U-series dates indicate a Substage 5a age. The setting of some of these deposits along a protected shoreline precludes discounting their position as anomalous due to large storms. This evidence that sea level in Bermuda was at about present datum late in Substage 5a agrees with interpretations of Neotyrrhenian deposits of Mediterranean shorelines, but not with inferences from the deep-sea oxygen-isotope record, or with data from uplifted coral reefs.
A systematic approach to performative and authentic assessment

Purpose – The purpose of this paper is to provide an overview of the learning outcomes assessment process and a five‐step, systematic approach for incorporating learning outcomes assessment into information literacy instruction. The paper focuses specifically on using performative and authentic assessments to measure higher‐level skills and ensure that students are able to perform the information literacy skills that library instruction programs intend to teach.Design/methodology/approach – The authors reviewed current assessment literature from both the information literacy and instructional design fields and pulled successful examples from their respective institutions in order to provide an overview of how best to incorporate performative and authentic assessment into the information literacy instruction process. This also includes discussions of assessment terminology, tools, and strategies.Findings – Engaging in learning outcomes assessment can be invaluable when performed as part of the information ...
Effects of Heavy Meson Exchange on the $D$ Wave Singlet and $F$ Wave Triplet $N N$ Partial Waves and the Question of Dibaryon Resonances

The $^{1}D_{2}$ and $^{3}F_{3}$ $N\ensuremath{-}N$ amplitudes are studied in a unitary dynamical model. Parameterfree long- and medium-range forces are given by multiple pion exchange, allowing coupling to the $\mathrm{NN}\ensuremath{\pi}$ channel. Short-range forces are mainly given by $\ensuremath{\rho}$ and $\ensuremath{\omega}$ exchange, parametrized to fit known low-energy phase shifts for $Jg~2$. Resulting Argand diagrams at medium energies show counter-clockwise loops, but far less dramatic than in the Hoshizaki phase-shift analysis. However, the results are similar to recent Arndt phase shifts.
The Qajar uymaq in the Safavid period, 1500–1722

(1978). The Qajar uymaq in the Safavid period, 1500–1722. Iranian Studies: Vol. 11, No. 1-4, pp. 117-143.
Characterization of Collagen Fibrils Films Formed on Polydimethylsiloxane Surfaces for Microfluidic Applications

Type I collagen fibrillar thin films have been prepared on hydrophobic recovered poly(dimethylsiloxane) (PDMS) surfaces and inside of irreversibly sealed PDMS microfluidic devices. Fibrillar films prepared on PDMS surfaces have been characterized with optical microscopy and atomic force microscopy and compared with films prepared using more traditional bulk methods on thiol-coated gold substrates. Collagen fibril films formed after 18 h of incubation on PDMS surfaces were observed to have similar underlying film thicknesses (15 nm), fibril size (67 nm), fibril coverage (45%), and physiologically supermolecular structure when compared to films on gold substrates. Collagen fibrils formed within devices were also determined to be usable across physiologically relevant cell perfusion rates. To validate the utility of these collagen fibril thin films for cell culture applications, vascular smooth muscle cells are shown to attach to collagen fibrils and exhibit cell spread areas equivalent to those seen on coll...
Use of lyophilised pig skin for donor site cover

Summary Reconstituted lyophilised pig-skin dressings have been used on skin graft donor sites. Their advantages are: They virtually eliminate all pain and discomfort from the donor sites. They allow earlier ambulation with comfort. By minimising the inflammatory reaction around the donor sites, pig-skin cover allows epithelialisation to proceed at an earlier date and the epithelium shows earlier maturation and organisation of the basal layers.
A polyhedron clipping and capping algorithm and a display system for three dimensional finite element models

This paper describes an algorithm for clipping and capping polyhedrons and a display system for three-dimensional finite element math models to facilitate viewing internal surfaces in the form of continuous tone computer generated color images. A plane is passed through the model with the result that the elements (or portions thereof) on one side of the plane may be eliminated. A new grid is generated for the cutting plane to include the prediction of such quantities as displacements, stresses, and temperatures. The Cutting plane is colored and/or warped to indicate the variation of selected scalar functions.
MLIS distance education at the University of South Carolina: report of a case study

In 1992, the University of South Carolina's College of Library and Information Science undertook the delivery of its American Library Association accredited Master of Library and Information Science degree program to a 3-year cohort of students in West Virginia and Georgia through a combination of live interactive telecommunications instruction and onsite class meetings in each state. After tracing the development of distance education at the University of South Carolina with emphasis on the College of Library and Information Science, the author describes a case study comparing the performance of this cohort of students with that of their counterparts in South Carolina. © 1996 John Wiley & Sons, Inc.
Use of aspirin for prevention of cardiovascular disease—1981–1982 to 1985–1986: The Minnesota Heart Survey

Abstract The efficacy of aspirin to prevent ischemic cardiovascular disease has received considerable attention recently. To determine the prevalence of aspirin use for cardiovascular disease prevention, the Minnesota Heart Survey examined population-based samples of Twin Cities' adults in 1981 to 82 and 1985 to 86. Over the 4-year period, reported use of aspirin for cardiovascular disease prophylaxis increased from 0.6% to 2.4% in women ( p p = 0.10). Prophylactic aspirin use was more common in older than in younger adults, in whites than in blacks, in those with a history of cardiovascular disease or hypercholesterolemia, and in health professionals and nonsmokers. Some individuals were apparently taking aspirin for “primary” prevention, although it has not yet been approved for that reason. Use of aspirin for cardiovascular disease prevention has been increasing and is likely to increase more rapidly over the next few years. This could favorably impact on mortality rates of cardiovascular disease, but untoward side effects of aspirin may be expected to increase as well.
A local composition model for multicomponent liquid mixture shear viscosity

Abstract A local composition model for multicomponent, nonaqueous, liquid mixture shear viscosity has been developed and tested. Only binary equilibrium thermodynamic information is used in the model in addition to pure component data. No mixture shear viscosities and no adjustable parameters are required. Predictions based on this model were compared to experimental data obtained from the literature and in this laboratory, yielding an average absolute deviation of 1.1% for ln(ηV) for 47 binary and 0.8% for seven ternary systems.
Model-driven architecture for agent-based systems

The Model Driven Architecture (MDA) approach uses a platform-independent model to define system functionality, or requirements, using some specification language. The requirements are then translated to a platform-specific model for implementation. An agent architecture based on the human cognitive model of planning, the Cognitive Agent Architecture (Cougaar) is selected for the implementation platform. The resulting Cougaar MDA prescribes certain kinds of models to be used, how those models may be prepared and the relationships of the different kinds of models. Using the existing Cougaar architecture, the level of application composition is elevated from individual components to domain level model specifications in order to generate software artifacts. The software artifacts generation is based on a metamodel. Each component maps to a UML structured component which is then converted into multiple artifacts: Cougaar/Java code, documentation, and test cases.
Speed of finger tapping and goal attainment after unilateral cerebral vascular accident

Abstract Objective: To determine (1) if speed of finger tapping is bilaterally slow after an acute unilateral cerebral vascular accident (CVA) and (2) if speed of finger tapping and grip strength are related to achieving rehabilitation goals during the first few weeks after stroke. Design: Prospective inception cohort study. Study Setting: Medical center and neurological institute. Participants: Fifty-one patients with unilateral CVAs. Main Outcome Measures: Documentation of goal attainment at discharge and bilateral measures of speed of finger tapping and grip strength. Results: Speed of finger tapping and grip strength were often bilaterally below normal limits after an acute unilateral CVA, with the contralateral hand most affected. Speed of finger tapping, but not grip strength, in the ipsilateral hand was associated with achieving rehabilitation goals. Speed of finger tapping in the contralateral hand as well as bilateral grip strength was not related to achievement of rehabilitation goals. Conclusions: Motor findings suggest that bilateral cerebral dysfunction may be common after an acute unilateral CVA. The speed of finger movement in the hand ipsilateral to the lesion may reflect the degree to which the so-called "unaffected" cerebral hemisphere has in fact maintained its functional integrity. As such, it may be a useful behavioral marker for predicting goal attainment during early stages of neurorehabilitation.
3D printing sandstone porosity models

The petroleum industry requires new technologies to improve the economics of exploration and production. Digital rock physics is a methodology that seeks to revolutionize reservoir characterization, an essential step in reservoir assessment, using computational methods. A combination of X-ray computed microtomography, digital pore network modeling, and 3D printing technology represents a novel workflow for transferring digital rock models into tangible samples that can be manufactured in a variety of materials and tested with standard laboratory equipment. Accurate replication of pore networks depends on the resolution of tomographic images, rock sample size, statistical algorithms for digital modeling, and the resolution of 3D printing. We performed this integrated approach on a sample of Idaho Gray Sandstone with an estimated porosity of 29% and permeability of 2200 mD. Tomographic images were collected at resolutions of 30 and ![Formula][1] per voxel. This allowed the creation of digital porosity models segmented into grains and pores. Surfaces separating pores from grains were extracted from the digital rock volume and 3D printed in plastic as upscaled tangible models. Two model types, normal (with pores as voids) and inverse (with pores as solid), allowed visualization of the geometry of the grain matrix and topology of pores, while allowing characterization of pore connectivity. The current resolution of commodity 3D printers with a plastic filament (![Formula][2] for pore space and ![Formula][3] for grain matrix) is too low to precisely reproduce the Idaho Gray Sandstone at its original scale. However, the workflow described here also applies to advanced high-resolution 3D printers, which have been becoming more affordable with time. In summary, with its scale flexibility and fast manufacturing time, 3D printing has the potential to become a powerful tool for reservoir characterization. [1]: /embed/mml-math-1.gif [2]: /embed/mml-math-2.gif [3]: /embed/mml-math-3.gif
Stratification of attitudes and skill level as correlated with knowledge and self confidence in a pre-engineering curriculum

It is well accepted that a solid background in the appropriate math and science classes prior to college is a key to success in pursuing careers in Engineering and Technology (E & T). Pre-engineering courses for K-12 students have repeatedly shown that they can help improve the skill level, and self-confidence of students as they enter the university E & T environment. This paper will examine student attitude and skill level as it related to the background knowledge and self confidence that students had during a three year summer pre-engineering camp conducted for urban high school students.
SAMAS: Scalable Architecture for Multi-resolution Agent-Based Simulation *

Large scale agent-based simulation has become the focus of great interest from both academy and industry in resent years. It has been shown an effective tool for understanding a variety of complex systems, such as market economics, war games, and epidemic propagation models. As the systems of interest grow in complexity, it is often desirable to have different categories of artificial agents that execute tasks on different time scales. With the added complexity, the scalability of a simulation environment becomes a crucial measure of its ability in coping with the complexity of the underlying system. In this paper, we present the design of SAMAS, a highly scalable architecture for multi-resolution agent-based simulation. SAMAS is a dynamic data driven application system (DDDAS) that adopts an efficient architecture that allows large number of agents to operate on a wide range of time scales. It uses gossiping, an efficient broadcasting communication model for maintaining the overall consistency of the simulation environment. We demonstrate the effectiveness of this communication model using experimental results obtained from simulation.
University Counselors Serve High Schools

Here is an interesting account of a service to high schools which developed from the regular personnel activities of Marquette University. The author describes the procedure followed in preparing the high school program and its record of 11 successful years.
A population genetic window into the past and future of the walleye Sander vitreus : relation to historic walleye and the extinct “blue pike” S. v. “glaucus”

Conserving genetic diversity and local adaptations are management priorities for wild populations of exploited species, which increasingly are subject to climate change, habitat loss, and pollution. These constitute growing concerns for the walleye Sander vitreus, an ecologically and economically valuable North American temperate fish with large Laurentian Great Lakes' fisheries. This study compares genetic diversity and divergence patterns across its widespread native range using mitochondrial (mt) DNA control region sequences and nine nuclear DNA microsatellite (μsat) loci, examining historic and contemporary influences. We analyze the genetic and morphological characters of a putative endemic variant– “blue pike” S. v. “glaucus” –described from Lakes Erie and Ontario, which became extinct. Walleye with turquoise-colored mucus also are evaluated, since some have questioned whether these are related to the “blue pike”. Walleye populations are distinguished by considerable genetic divergence (mean FST mtDNA = 0.32 ± 0.01, μsat = 0.13 ± 0.00) and substantial diversity across their range (mean heterozygosity mtDNA = 0.53 ± 0.02, μsat = 0.68 ± 0.03). Southern populations markedly differ, possessing unique haplotypes and alleles, especially the Ohio/New River population that houses the oldest haplotype and has the most pronounced divergence. Northern formerly glaciated populations have greatest diversity in Lake Erie (mean heterozygosity mtDNA = 0.79 ± 0.00, μsat = 0.72 ± 0.01). Genetic diversity was much less in the historic Lake Erie samples from 1923–1949 (mean heterozygosity mtDNA = 0.05 ± 0.01, μsat = 0.47 ± 0.06) than today. The historic “blue pike” had no unique haplotypes/alleles and there is no evidence that it comprised a separate taxon from walleye. Turquoise mucus walleye also show no genetic differentiation from other sympatric walleye and no correspondence to the “blue pike”. Contemporary walleye populations possess high levels of genetic diversity and divergence, despite habitat degradation and exploitation. Genetic and previously published tagging data indicate that natal homing and spawning site philopatry led to population structure. Population patterns were shaped by climate change and drainage connections, with northern ones tracing to post-glacial recolonization. Southerly populations possess unique alleles and may provide an important genetic reservoir. Allelic frequencies of Lake Erie walleye from ~70–90 years ago significantly differed from those today, suggesting population recovery after extensive habitat loss, pollution, and exploitation. The historic “blue pike” is indistinguishable from walleye, indicating that taxonomic designation is not warranted.
Measuring the Effectiveness of Hierarchical Address Assignment

Hierarchical, topology-based addressing has long been considered crucial to routing and forwarding scalability. Recently, however, a number of research efforts are considering alternatives to this traditional approach. With the goal of informing such research, we investigated the efficiency of address assignment in the existing (IPv4) Internet--that is, the assignment of prefixes to ASes. In particular, we ask the question: ``Exactly how much does addressing hierarchy help us at the interdomain level?'''' To do so, we first define a notion of efficiency or locality based on the total number of bit-hops required to advertise all prefixes in the Internet in BGP, and compute this quantity for the current Internet using RouteViews data. In order to quantify how far from
AVCast : New Approaches For Implementing Availability-Dependent Reliability for Multicast Receivers

Today?s large-scale distributed systems consist of collections of nodes that have highly variable availability - a phenomenon sometimes called churn. This availability variation is often a hindrance to achieving reliability and performance for distributed applications such as multicast. This paper looks into utilizing and leveraging availability information in order to provide availability-dependent message reliability for multicast receivers. An application (e.g., a publish-subscribe system) may want to scale the multicast message reliability at each receiver according to that receiver?s availability (in terms of the fraction of time that receiver is online) - different options are that the reliability is independent of the availability, or proportional to it.. We propose several gossip-based algorithms to support several such predicates. These techniques rely on each node?s availability being monitored in a distributed manner by a small group of other nodes in such a way that the monitoring load is evenly distributed in the system. Our techniques are light-weight, scalable, and are space- and timeefficient. We analyze our algorithms and evaluate them experimentally by injecting availability traces collected from real peer-to-peer systems.
Iterative Decoding for Serial Concatenated System of VLEC and Recursive STTC

In this paper, we consider serially concatenated source and space time systems. Recursive space time Trellis code (Rec-STTC) with high order modulation is used to provide high bandwidth efficiency. Variable length error correcting code (VLEC) is adopted to provide error resilient capacity at the source coding side. We propose an iterative joint source and space time decoding scheme. The maximum a posteriori probability (MAP) decoding algorithm is adjusted to accommodate issues including the information in both bit and symbol domains and the inseparable systematic information. Systems with a fixed overall information rate but different coding rates in component codes are studied. Simulation results indicate that the proposed joint source space time decoding scheme achieves a significant decoding gain in both quasi-static and rapid fading channels. In addition, for a system with more redundancy dedicated to the source code and a higher order modulation of STTC, the joint decoding yields better performance, though with increased complexity.
Flattopped tunable wavelength-division-multiplexer filter design

We present what is to our knowledge the first design of a tunable optical filter with a flattopped passband. The filter consists of a Fabry-Perot etalon with multiple reflection gratings as dielectric mirrors. Wavelength tunability is achieved by modulation of the refractive indices of the cavity and the dielectric mirrors. Specifically, a filter with a 1-nm linewidth and a 40-nm wavelength-tuning range is designed for applications in wavelength-division-multiplexing (WDM) optical fiber communication systems. We also discuss several factors, including absorption and variations of other design parameters, that may affect the performance of the filter.
Indeterminacy, Incompleteness, Indecision, and Other Semantic Phenomena

This paper explores the relationships between Davidson's indeterminacy of interpretation thesis and two semantic properties of sentences that have come to be recognized recently, namely semantic incompleteness and semantic indecision. More specifically, I will examine what the indeterminacy thesis entails for sentences of the form ‘By sentence S (or word w), agent A means that m’ and ‘Agent A believes that p.’ My primary goal is to shed light on the indeterminacy thesis and its consequences. I will distinguish two kinds of indeterminacy that have very different sources and very different consequences. But this does not purport to be an exhaustive study: there may well be other forms of indeterminacy that this paper does not address. I will first explain the phenomena of semantic incompleteness and semantic indecision, and then explore their relationships with the indeterminacy thesis.
Horizontal Violence Among Hospital Staff Nurses Related to Oppressed Self or Oppressed Group

Horizontal violence among nurses is recognized as a major problem in hospitals; however, the origins and effects on patient care have not been studied. This study described the incidence of horizontal violence among hospital staff RNs and tested 2 hypotheses about the social origins of this behavior. A random sample of 175 hospital staff RNs drawn from the California Board of Registered Nursing's mailing list was surveyed. Horizontal violence was reported by 21.1% (n = 37) of participating nurses. Hypotheses were supported. Findings suggested (a) a positive relationship between beliefs consistent with an oppressed self and horizontal violence (r = .434, P < .05) and (b) a positive relationship between beliefs consistent with those of an oppressed group and horizontal violence (r = .453, P < .05). A change in the oppressive social structure of hospitals may be needed to truly address horizontal violence in the best interest of the quality and safety of patient care.
Effect of rural residence on use of VHA mental health care among OEF/OIF veterans.

Objective:The Veterans Health Administration (VHA) has worked to increase availability of mental health treatment for rural veterans. The objective was to understand the impact of rural residence on screening for, diagnosis of, and treatment for depression and posttraumatic stress disorder (PTSD) among veterans of Operation Enduring Freedom and Operation Iraqi Freedom (OEF/OIF) using VHA care.Methods:A cohort of veterans from a five-state region was identified whose first VHA clinic visit occurred between January 1, 2008, and March 17, 2009. The cohort was retrospectively followed for three months to identify a cohort who used VHA care at least twice.Results:The sample included 4,782 OEF/OIF veterans known to be using VHA care; mean age was 31 years (range 18–64); most were male (88%). Screening rates were 85% for depression and 84% for PTSD. Compared with veterans in small or isolated rural towns, those in urban areas were less likely to be diagnosed as having PTSD (odds ratio [OR]=.79, 95% confidence in...
Wishful Thinking or Buying Time? The Logic of British Appeasement in the 1930s

Scholars typically define appeasement as a policy of satisfying grievances through one-sided concessions to avoid war for the foreseeable future and, therefore, as an alternative to balancing. They traditionally interpret British appeasement of Adolf Hitler in the 1930s as a naive attempt to maintain peace with Germany by satisfying his grievances. The standard conceptualization of appeasement and the empirical treatment of the 1930s, however, are theoretically limiting and historically incorrect. Appeasement is a strategy of sustained, asymmetrical concessions with the aim of avoiding war, at least in the short term. There are three distinct variations of appeasement: (1) resolving grievances (to avoid war for the foreseeable future); (2) diffusing secondary threats (to focus on a greater threat); and (3) buying time (to rearm and/or secure allies against the current threat). British appeasement was primarily a strategy of buying time for rearmament against Germany. British leaders understood the Nazi me...
Osteogenic Effect of Ashed Bone in Fixation of Hip Implants

The purpose of this work is to discuss the role of ashed bone reinforced Ultra-High Molecular Weight Polyethylene, UHMWPE, biocomposite in bringing about early biological fixation of hip implant by combining the high damping capacity of this composite with the osteogenic characteristic of ashed bone. This paper will present the damping results obtained for this composite containing 65 weight% ashed bone over a range of frequencies, 0.1-100 rad/s, using a forced vibration technique. Some of the data obtained for lower ash content compositions are compared. The structural characteristics of bone and ashed bone are illustrated using x-ray diffractometry, XRD, and scanning electron microscopy, SEM. The optimal ashing temperature and volume fraction of ashed bone are also significant parameters which will be discussed. The 65 weight % ashed bone composite was elected to simulate the bone mineral content and use as a bioactive agent for the enhancement of bone ingrowth in the early days post-implantation.
Superporous hydrogels for cartilage repair: Evaluation of the morphological and mechanical properties

Despite extensive research in the design of biomaterials for articular cartilage repair, there remains a need for the development of materials with the mechanical compliance to function synergistically with healthy cartilage, but porous enough to allow for tissue integration. In this study, superporous hydrogels of poly(vinyl alcohol) and poly(vinyl pyrrolidone) were prepared using a novel technique consisting of a double emulsion process. The hydrogel emulsions were physically cross-linked by freeze-thaw cycling. The hydrogels had a high degree of porosity, determined using environmental scanning electron microscopy, a technique superior to any method that involves dehydrating the samples. Increasing the volume of organic solvent increased porosity, due to cross-linking of the hydrogel solution around the droplets in the emulsion, leaving pores where the organic solvent was present. Poly(lactic-co-glyclic acid) microparticles formed and were embedded in the matrix. The mechanical properties, measured in confined creep and in unconfined, uniaxial compression, were similar to native articular cartilage. The permeability of the samples was unaffected by changing solvent content, despite changes in porosity. These materials are good candidates for tissue engineering of cartilage because they can mimic mature cartilage mechanically while providing a porous matrix through which cells can migrate and proliferate.
Toward an Integrative Medicine: Merging Alternative Therapies with Biomedicine

Toward an Integrative Medicine: Merging Alternative Therapies with Biomedicine. Hans Baer. Lanham, MD: AltaMira Press, 2005. 203 pp.
Disinfection of American Foulbrood Combs by Fumigation with Formaldehyde.—II

(1931). Disinfection of American Foulbrood Combs by Fumigation with Formaldehyde.—II. Bee World: Vol. 12, No. 2, pp. 16-19.
On Estimation of Plant Dynamics and Disturbance from Input-Output Data in Real Time

This paper is concerned with the question of, for a physical plant to be controlled, whether or not its internal dynamics and external disturbances can be realistically estimated in real time from its input-output data. A positive answer would have significant implications on control system design, because it means that an accurate model of the plant is perhaps no longer required. Based on the linear extended state observer (LESO), it is shown that, for a nth order plant, the answer to the above question is indeed yes. In particular, it is shown that the estimation error (1) converges to the origin asymptotically when the model of the plant is given; (2) is bounded and inversely proportional to the bandwidth of the observer when the plant model is mostly unknown. Note that this is not another parameter estimation algorithm in the framework of adaptive control. It applies to a large class of nonlinear, time-varying processes with unknown dynamics. The solution is deceivingly simple and easy to implement. The results of the mathematical analysis are verified in a simulation study and a motion control hardware test.
Sensitization of mice to methylphenidate.

Mice that received five daily injection of methylphenidate HCl, 10–75 mg/kg, showed an increased running response to methylphenidate, cocaine, and amphetamine. Sensitization to methylphenidate persisted for at least 50 days. Repeated IP injections of methylphenidate into mice with unilateral striatal lesions increased ipsilateral turning in response to methylphenidate, but decreased contralateral turning after apomorphine. The climbing response to apomorphine in intact, methylphenidate-sensitized mice was also decreased. There was no change in either basal or dopamine-stimulated adenyl cyclase activity in the striata of sensitized mice, but there was a 36% increase in the specific binding of haloperidol. The rate of turnover of striatal dopamine was increased in sensitized mice. These results suggest that pretreatment with methylphenidate may alter the sensitivity of presynaptic dopamine receptors.
Induction of Lymphokine-activated Killer Activity by Interleukin 4 in Human Lymphocytes Preactivated by Interleukin 2 in Vivo or in Vitro

In an attempt to augment the generation of human cytotoxic effector cells for potential cancer therapy with interleukin 2 (IL2) and lymphokine-activated killer (LAK) cells, the effect of interleukin 4 (IL4) on LAK cell induction was studied. In normal human peripheral blood lymphocytes (PBL), IL4 does not induce LAK activity and inhibits LAK induction by IL2. However, since lymphocyte activation, such as with antigen or mitogen, can render them responsive to IL4, the ability of IL4 to induce LAK activity in lymphocytes preactivated in vivo or in vitro with IL2 was investigated. PBL obtained from 12 patients with advanced cancer 1 to 3 days after IL2 therapy and from eight healthy control subjects were cultured 4 to 5 days with or without IL4 and/or IL2 and then tested for LAK activity as assessed by lysis of Daudi in a 4-h 51Cr release assay. In normal PBL, IL4 failed to induce LAK activity and consistently inhibited LAK induction by a suboptimal concentration of IL2 (10 units/ml). By contrast, IL4 induced LAK activity in PBL from seven of twelve IL2-treated patients and augmented LAK induction by the suboptimal IL2 in PBL from five of twelve IL2-treated patients. With an optimal LAK-inducing concentration of IL2 (1000 units/ml), IL4 less consistently inhibited LAK induction in normal PBL and had a variable effect upon LAK induction in PBL from IL2-treated patients. IL4 induced LAK activity in PBL obtained from a cancer patient after, but not before, systemic IL2 therapy. Similarly, IL4 induced LAK activity in normal PBL only after they had been preincubated with IL2. Thus, IL4 induces LAK activity in lymphocytes preactivated by IL2 in vivo or in vitro . Fluorescence-activated cell sorting revealed that the LAK activity, whether induced by IL4 or by IL2, was mediated largely by non-T (CD5-) natural killer-like (CD56+) cells. The results suggest a regulatory relationship between IL2 and IL4 in the induction and/or maintenance of LAK activity, which might be exploited to augment the generation of cytotoxic cells for lymphokine-mediated immunotherapy of human cancer.
Online Medline plus Fan Search V Offsearch: A Comparison of Literature Retrieval Methods

Medline is a computerized indexing and abstracting service for biomedical literature and is one of the most commonly used methods of literature retrieval. An alternative manual technique is fan searching. Fan searching involves scanning bibliographies of relevant articles from online Medline searches of the most current literature. We compared the amount of relevant literature retrieval between these two methods. We conducted 14 searches, which were randomly selected from typical drug information questions answered in our center. Overall only 20% of the references from computerized offsearches were identified by manual fan searching. In only one instance did fan searching identify greater than 50% of the same citations listed in the offsearch. We conclude that fan searching is not a comprehensive method of literature retrieval.
Depression and Thought Intrusions, Relating Thought Frequency to Activation and Arousal

Laboratory studies have demonstrated that task-unrelated image and thought (TUIT) likelihood decreased with increased age, displayed a circadian rhythm, and increased with hyperactivity; these outcomes are consistent with the speculation that TUIT production is directly related to brain activation/arousal level. We examined the association between TUIT likelihood and depression and anxiety and their putative activation/arousal levels. Individuals diagnosed with a major depressive disorder reported TUITs while performing a vigilance task. Significant, p < .05, correlations indicated that deeper depression, dejection, and perceived fatigue were associated with a reduced likelihood of unintentional TUITs and greater anxiety were associated with increased likelihood of unintentional TUITs. These results were consistent with an association between arousal/activation and unbidden TUIT likelihood.
Analysis and design of self-oscillating flyback converter

The self-oscillating flyback converter is a popular circuit for cost-sensitive applications due to its simplicity and low component count. It is widely employed in mobile phone chargers and as the stand-by power source in off-line power supplies for data-processing equipment. However, the optimization of this circuit is almost exclusively performed by a cut-and-dry approach since its operation is generally not well understood. This paper presents a detailed steady-state analysis of the self-oscillating flyback converter along with its small-signal model. Design guidelines of the control circuit and loop compensation are presented and verified on an offline, stand-by, 5 V/2 A power supply.
Lysine need of heavy broiler males applying the ideal protein concept

An experiment was conducted to determine arginine need of male broilers between the ages of 42 to 56 d, in conjunction with dietary protein approaching a previously advocated ideal amino acid pattern. Ross x Ross 308 chicks were reared in floor pens (32 pens with 35 birds each) of an open-sided house on common feeds until 42 d of age. From 42 to 56 d of age, birds were fed a corn-soybean meal diet (17% CP, 3,250 kcal/kg ME, and 0.85% lysine) having basal arginine at 0.80%, and then progressive additions of 0.15% were made until 1.25% was reached to form the dietary treatments. Final body weight together with body weight gain and feed conversion through the 42-to-56-d experimental period were optimized at 0.98% arginine. Weight of the chilled carcass was optimized at 1.00% arginine, whereas depot fat that had been removed from the abdominal cavity continued to decrease to the highest level of supplementation. Additional total arginine to 1.05% was needed to maximize weight recovery of fillets and total breast meat. An arginine requirement for nutritional purposes approximating 1.00% as advocated by NRC (1994) is in general agreement with present results for live production and meat yield; however, carcass incidence of skin scratch infections and parts defects from processing stresses continually responded until the highest level to suggest that additional amounts would be needed for immunological and connective tissue challenges.
No association between genetic polymorphisms in IGF-I and IGFBP-3 and prostate cancer

High levels of circulating insulin-like growth factor-I (IGF-I), or IGF-I in relation to IGF binding protein-3 (IGFBP-3), have been associated with an increased risk of prostate cancer (CaP) and other common epithelial cell malignancies ([1][1]). Twin studies estimate that 38% of the interindividual
Pulse Oximeter Plethysmograph Estimate of Pulsus Paradoxus as a Measure of Acute Asthma Exacerbation Severity and Response to Treatment

Objectives Pulsus paradoxus is one of the few objective bedside measures of acute asthma exacerbation severity but is difficult to measure in tachypneic and tachycardic patients and in noisy clinical environments. Our primary objective was to examine whether pulse oximeter plethysmograph estimate of pulsus paradoxus (PEP) is associated with physiologic and symptom measures of acute exacerbation severity (airway resistance by impulse oscillometry [%IOS] and the Acute Asthma Intensity Research Score [AAIRS]). Secondary objectives were to validate the previous association of PEP with percent predicted forced expiratory volume in 1 second (%FEV1) and to examine associations of change of PEP with change of these outcomes after 2 hours of treatment. Methods This was a secondary analysis of data from a prospective observational study of patients aged 5–17 years with acute asthma exacerbations. The predictor variable, PEP, was measured using a dedicated pulse oximeter and waveform analysis program. Outcome measures included the AAIRS, %IOS, and %FEV1 at baseline and after 2 hours of treatment. We examined associations of PEP with %IOS and the AAIRS at baseline using multiple linear regression models adjusted for age, sex, and race. As secondary analyses we similarly examined the association of PEP with %FEV1 at baseline and change of PEP with change of %IOS, the AAIRS, and %FEV1 after 2 hours of treatment using multiple linear regression models adjusted for the baseline value of the outcome measure and the AAIRS. Results Among 684 participants (61% males; 61% African American) there were associations of baseline PEP with %IOS, the AAIRS, and %FEV1 (p < 0.001). Change of PEP after 2 hours of treatment was associated with change of %FEV1 (p < 0.001) and change of the AAIRS (p = 0.01) but not with change of %IOS (p = 0.60). Conclusions PEP demonstrates criterion validity in predicting baseline %IOS, the AAIRS, and %FEV1, and responsiveness to change of the AAIRS and %FEV1. Data contained in the oximeter plethysmograph waveform might be utilized as a continuous, objective measure of acute asthma exacerbation severity and real-time response to treatment.
Seeing mTORC1 specificity

Cells must sense their environment to determine whether conditions are suitable for growth. Despite the physiological importance of a multiprotein complex called mammalian/mechanistic target of rapamycin complex 1 (mTORC1) in this process, a detailed molecular understanding of its assemblage and regulation of its serine-threonine kinase function have proven difficult to elucidate. On page 48 of this issue, Aylett et al. ( 1 ) help uncover the molecular underpinnings of mTORC1, while on pages 43 and 53, Wolfson et al. ( 2 ) and Saxton et al. ( 3 ), respectively, make strides in determining how mTORC1 is regulated by the amino acid leucine.
Cellular mechanisms involved in carotid body inhibition produced by atrial natriuretic peptide.

Atrial natriuretic peptide (ANP) and its analog, atriopeptin III (APIII), inhibit carotid body chemoreceptor nerve activity evoked by hypoxia. In the present study, we have examined the hypothesis ...
Seamless blended learning using the Cognitive Learning Companion: A systemic view

We present the motivation, design, and preliminary study of a mobile-enabled, blended learning technology called the Cognitive Learning Companion (CLC). The CLC concept emerged from field studies with teachers and students in Africa. These studies led to two key high-level requirements that shaped the design philosophy of CLC: 1) seamless support for different modes of learning and teaching in a blended scenario (where a student learns in part through face-to-face interactions with a teacher in a classroom, and in part through a combination of teacher and system supervision/direction outside of class) and 2) support for tracking student engagement and sentiment during this blended learning journey, and the interplay of these affective processes with concept and skill-building processes as part of learning. In this paper, we discuss findings from the field studies and outline our approach to address the requirements. We present the overall architecture and design of CLC. The first version supporting a core set of capabilities for blended learning has been implemented as mobile applications for teachers and students. We conducted a limited pilot to test the technology in an actual classroom setting. We also report on a usability study of CLC that demonstrates user awareness and support for data-driven cognitive decision-making in education.