cssi/SciSciGPT-SciSciNet huggingface dataset:
Tumbling for Stealth

One of the most remarkable and pervasive feats in the microscopic world is the coordination of flagella, the slender, whiplike structures that protrude from many types of cells. The collective motion of flagella (also known as cilia when they occur in large numbers in eukaryotes) drives fluid transport ( 1 ), and permits individuals to save energy through cooperation ( 2 ). Because the internal structure of cilia is highly conserved among eukaryotes from algae to humans, free-swimming organisms like Chlamydomonas (see the first figure, panel A) have long been powerful model systems ( 3 ). On page 487 of this issue, Polin et al. ( 4 ) show how synchronization of the flagella in Chlamydomonas reinhardtii governs the movement of this green alga through water, a key determinant of its ecological fitness.
The deformation behavior of a vanadium-strengthened dual phase steel

A study has been made of the mechanical properties of dual phase (martensite plus ferrite) structures produced when a V containing HSLA steel is cooled in a controlled manner from either the austenite or austenite plus ferrite phase fields. Such a heat treatment results in the pearlite regions and carbide particles of the standard V steel being replaced by martensite; this leads to a decrease in the yield stress and an increase in ductility while the tensile strength is essentially unchanged. The fatigue of dual phase steels is slightly superior in the high strain life (ductility controlled) region and slightly inferior in the low strain life (yield dominated) region when compared to standard V steel. The replacement of the pearlite and cementite particles which can nucleate cracks, by more ductile martensite islands results in improved Charpy impact properties. The strength and the ductility of the dual phase materials is shown to be in agreement with a theory of composites with two ductile phases. This theory then allows one to understand the relative importance of various microstructural features in controlling strength and ductility. In this way it is found that the key to the superior elongation (at a constant tensile strength) is largely due to the high strength (fine grained), highly ductile ferrite matrix.
A hierarchical modeling approach to accelerated degradation testing data analysis: A case study

In this case study, we investigate the degradation process of light-emitting diodes (LEDs), which is used as a light source in DNA sequencing machines. Accelerated degradation tests are applied by varying temperature and forward current, and the light outputs are measured by a computerized measuring system. A degradation path model, which connects to the LED function recommended in Mitsuo (1991), is used in describing the degradation process. We consider variations in both measurement errors and degradation paths among individual test units. It is demonstrated that the hierarchical modeling approach is flexible and powerful in modeling a complex degradation process with nonlinear function and random coefficient. After fitting the model by maximum likelihood estimation, the failure time distribution can be obtained by simulation. Copyright © 2010 John Wiley & Sons, Ltd.
Analysis of carrier ampholytes by ion exchange chromatography.

Commercially available and synthetic wide-range and short-range ampholytes used in the isoelectric focusing of proteins were analyzed by ion-exchange chromatography. A pH gradient over the pH range 3.8 to 11.0 was used to elute the ampholytes from a column of a sulfonated polystyrene resin. The wide-range ampholytes were resolved into some 60 to 70 ninhydrin-positive components. The recovery obtained with the method was quantitative. Analysis of the cathodic and anodic fractions of wide-range ampholytes focused concurrently with whale myoglobin on a polyacrylamide gel, suggested that no simple relationship exists between the pI of the ampholyte components and the pH at which they are eluted from the ion-exchange column.
Philosophy as a practice for life

Abstract The following is a case study of a client who received individual philosophical counseling from a private practice. The client attended for five 1-hour sessions over a period of 2 months. Client details and locations have been altered to protect the client's true identity and confidence. The name of “Tim” is pseudonymous.
An asymptotic approach to the connection problem for the first and the second painlevé equations

Abstract A new asymptotic method of attack on the connection problem around the point at infinity for Painleve transcendents of the first and second kind is developed. Connection results between two general angles of approach to infinity, not on special sector boundaries, are obtained for generic four-real-parameter asymptotic behaviours of the Painleve transcendent. Here the term generic means that two of the four free real parameters are constrained to be nonzero.
Computations of Slowly Moving Shocks

Computations of slowly moving shocks by shock capturing schemes may generate oscillations that appear as a wavy tail attached to the shock front. These oscillations are generated already by first-order schemes, but become more pronounced in higher-order schemes due to their lower dissipation. We focus on two first-order schemes which seem to exhibit different behaviors: (i) the first-order upwind (UW) scheme which generates strong oscillations and (ii) the Lax?Friedrichs scheme which appears not to generate any disturbances at all. A key observation is that in the UW case, the numerical viscosity in the shock family vanishes inside the slow shock layer. Simple scaling arguments show that third-order effects on the solution may no longer be neglected. We derive the third-order modified equation for the UW scheme and regard the oscillatory solution as a traveling wave solution of the parabolic modified equation plus a small perturbation. We then look at the governing equation for the perturbation, which points to a plausible mechanism by which postshock oscillations are generated. It contains a third-order source term that becomes significant inside the shock layer, and a nonlinear coupling term which projects the perturbation on all characteristic fields, including those not associated with the shock family.
Determination of serotonin, its precursors, metabolites and [3H]serotonin in lung by high-performance liquid chromatography with fluorescence detection

Abstract A rapid, simple, sensitive method for the determination of serotonin, its precursors, metabolites and [3H]serotonin in lung is described. Tissue preparation requires only homogenization in dilute perchloric acid and centrifugation prior to separation by high-performance liquid chromatography using a reversed-phase column. Detection is based on the native fluorescence of indole compounds and detection limits ranged between 30–90 pg injected. The method has been used to determine these compounds in mouse lung and plasma.
Consumer Responses to the CPA WEBTRUST™ Assurance

With the advent of WEBTRUST™, accountants are providing assurances about online transactions to consumers who may otherwise hesitate to engage in electronic commerce. This study explores the influence of assurance services on consumers' online transaction expectations and intent to purchase online. In short, the study supports the notion that many of the marketing efforts associated with WEBTRUST™ can have desirable effects on consumer behavior. Results suggest that consumers who pay more attention to the WEBTRUST™ seal and disclosures at the web site or who have been exposed to WEBTRUST™ advertising have higher online transaction expectations and stronger intent to purchase online than their counterparts. Similarly, consumers' knowledge about CPAs positively influences their online transaction expectations, but not intent to purchase online. However, the study also indicates areas of concern for practitioners and researchers. Only 56 percent of subjects noticed the seal, 27 percent clicked on the seal, a...
The dynamics of commensalism

The outcome of the interaction of two commensal populations growing in a continuous bioreactor depends on the operating conditions (dilution rate and feed concentration) and the shape and mutual disposition of the specific growth rate curves of the two populations. The stability of the possible steady states is analyzed by a new method based on the Poincare index and a comprehensive portrait of the dynamics of the interaction of commensalism is presented. Potential operating difficulties and associated control problems are discussed.
Real-time adaptive motion planning for a continuum manipulator

Continuum manipulators, featuring “continuous backbone structures”, are promising for deft manipulation of a wide range of objects under uncertain conditions in less-structured and cluttered environments. A multi-section trunk/tentacle robot is such a continuum manipulator. With a continuum robot, manipulation means a continuous whole-arm motion, often without a clear distinction between transport and grasping. In this paper, we address the novel problem of real-time motion planning for such a robot under uncertain conditions. We present an algorithm for on-line planning the motion of a planar continuum robot for grasping a target object amid an environment of other objects with uncertain movements. Our algorithm substantially extends the RAMP paradigm [19] for real-time adaptive motion planning to this new form of whole-arm manipulation. Simulation results are promising, demonstrating the effectiveness of our approach.
Observations of abyssal flow and mixing

Scientists once thought the abyssal ocean, near the ocean bottom, was nearly stagnant, but recent observations show it is quite dynamic and that abyssal mixing plays an important role in the general circulation. Contributing to understanding of abyssal flow,Alford et al. report measurements of temperature and velocity in the abyssal ocean from two moorings near Hawaii. They found three major cold events in their 2.5-year record, indicating that mixing events are strongly intermittent. They focus in detail on one unusual cold event that appeared in two pulses spaced about 2 weeks apart in September and October 2010. The event included an anomalously low temperature about 0.15°C below normal temperatures that extended more than 500 meters above the ocean bottom as well as vigorous turbulent flows. (Geophysical Research Letters, doi:10.1029/2011GL048075, 2011)
Economies of scale in steam-electric power generation in East-North-Central U.S.

In this study the author investigates firm-level cross-sectional unit cost advantages for electricity generation for 31 regulated private steam-electric utilities in East-North-Central U.S. region during 1987. The production technology is modeled using the implied dual minimum total variable cost translog methodology. Estimates of Zellner’s Seemingly Unrelated Regressions indicate a smooth non-homothetic technology, a typical regional firm-level scale economies of about 0.263, and an implied mean cost-output elasticity of about 0.737. Significant scale economies exist for several of the smaller utilities. The findings support policies which steer energy-intensive industrial location decisions in a direction which captures unutilized unit cost economies in electricity generation.
CDSchecker: checking concurrent data structures written with C/C++ atomics

Writing low-level concurrent software has traditionally required intimate knowledge of the entire toolchain and often has involved coding in assembly. New language standards have extended C and C++ with support for low-level atomic operations and a weak memory model, enabling developers to write portable and efficient multithreaded code.Developing correct low-level concurrent code is well-known to be especially difficult under a weak memory model, where code behavior can be surprising. Building reliable concurrent software using C/C++ low-level atomic operations will likely require tools that help developers discover unexpected program behaviors.In this paper we present CDSChecker, a tool for exhaustively exploring the behaviors of concurrent code under the C/C++ memory model. We develop several novel techniques for modeling the relaxed behaviors allowed by the memory model and for minimizing the number of execution behaviors that CDSChecker must explore. We have used CDSChecker to exhaustively unit test several concurrent data structure implementations on specific inputs and have discovered errors in both a recently published C11 implementation of a work-stealing queue and a single producer, single consumer queue implementation.
Demonstration of cholinergic cells in human neuroblastoma and ganglioneuroma.

REFERENCES 1. Zellweger, H., White, C., and Kretzschmar, R. M.: Prenatal genetics and eytogenetics, J. Iowa Med. Soc. 61: 546, 1971. 2. Zellweger, H., White, C., and Kretzschmar, R. M.: Praenatale Geschlechtsbestimmung und Zytogenetik, Schweiz. Med. Wochenschr. 101: 1400, 1971. 3. Penrose, L. S., and Smith, G. F.: Down's anomaly, London, 1966, J. & A. Churchill, Ltd. 4. Nadler, H. L.: Personal communication. 5. Lilienfeld, A. M.: Epidemiology of mongolism, Baltimore, 1969, The Johns Hopkins Press. 6. Wright, S. W., Crandall, B. F., and Boyer, L.: Perspectives in cytogenetics, Springfield, Ill., 1972, Charles C Thomas, Publisher.
Interactive informed consent: randomized comparison with paper consents.

Informed consent is the cornerstone of human research subject protection. Many subjects sign consent documents without understanding the study purpose, procedures, risks, benefits, and their rights. Proof of comprehension is not required and rarely obtained. Understanding might improve by using an interactive system with multiple options for hearing, viewing and reading about the study and the consent form at the subject’s own pace with testing and immediate feedback. This prospective randomized study compared the IRB-approved paper ICF for an actual clinical research study with an interactive presentation of the same study and its associated consent form using an iPad device in two populations: clinical research professionals, and patients drawn from a variety of outpatient practice settings. Of the 90 participants, 69 completed the online test and survey questions the day after the session (maximum 36 hours post-session). Among research professionals (n = 14), there was a trend (p = .07) in the direction of iPad subjects testing better on the online test (mean correct = 77%) compared with paper subjects (mean correct = 57%). Among patients (n = 55), iPad subjects had significantly higher test scores than standard paper consent subjects (mean correct = 75% vs 58%, p < .001). For all subjects, the total time spent reviewing the paper consent was 13.2 minutes, significantly less than the average of 22.7 minutes total on the three components to be reviewed using the iPad (introductory video, consent form, interactive quiz). Overall satisfaction and overall enjoyment slightly favored the interactive iPad presentation. This study demonstrates that combining an introductory video, standard consent language, and an interactive quiz on a tablet-based system improves comprehension of research study procedures and risks.
An automatic unsupervised classification of MR images in Alzheimer's disease

Image-analysis methods play an important role in helping detect brain changes in and diagnosis of Alzheimer's Disease (AD). In this paper, we propose an automatic unsupervised classification approach to distinguish brain magnetic resonance (MR) images of AD patients from those of elderly normal controls. The symmetric log-domain diffeomorphic demons algorithm, with the properties of symmetry and invertibility, is used to compute the pair-wise registration, whose deformation field is then used to calculate the Riemannian distance between them. The spectral embedding algorithm is performed based on the Riemannian distance matrix to project images onto a low-dimensional space where each image is represented as a point and its neighboring points correspond to images of high anatomical similarity. Finally, the quick shift clustering method is employed in the embedded space to partition the dataset into subgroups. The experiments using the proposed method show very good performance for clustering images into AD and normal aging, using the Clinical Dementia Rating (CDR) scale as a comparison.
Ultrastable CO 2 Laser Trapping of Lithium Fermions

We demonstrate an ultrastable ${\mathrm{CO}}_{2}$ laser trap that provides tight confinement of neutral atoms with negligible optical scattering and minimal laser-noise-induced heating. Using this method, fermionic ${}^{6}\mathrm{Li}$ atoms are stored in a 0.4 mK deep well with a $1/e$ trap lifetime of 300 sec, consistent with a background pressure of ${10}^{\ensuremath{-}11}\mathrm{Torr}$. To our knowledge, this is the longest storage time ever achieved with an all-optical trap, comparable to the best reported magnetic traps.
KINETICS OF GRAFTING IN SOLUTION POLYMERIZATION

A mechanistic kinetic model, which includes several elementary reactions occurring simultaneously, is developed for the kinetics of grafting in solution polymerization. This model allows prediction of the rate of polymerization and grafting efficiency under various reaction conditions. It also permits evaluation of grafting reaction rate constants. Experimental data available in the literature are used to test the model. Very good agreement is observed between the data and model predictions.
Asymptotic Invariants in Gravitational Radiation Fields

Asymptotic integral invariants are constructed for the electromagnetic and gravitational fields. The integrals are taken over closed two-dimensional surfaces embedded in a null hypersurface. In the absence of incoming radiation, the asymptotic behavior of the electromagnetic field ${F}^{\mathrm{ab}}$ and the Riemann tensor ${R}^{\mathrm{abcd}}$ is such that the integrals formed with these quantities are independent of the particular space-like surface of integration, as long as it lies in the same null hypersurface. Therefore, the integrals are related to the multipole structure of the charge distribution and the matter distribution, respectively. This relationship is shown explicitly for the electromagnetic field and for the linearized gravitational field. It follows that energy radiation as determined by the Einstein pseudotensor depends on the existence of a type III asymptotic behavior of the Riemann tensor. Finally, the asymptotic conditions are formulated under which the superpotential ${{U}_{m}}^{\mathrm{ns}}$ will also lead to asymptotically invariant integrals. It is pointed out that the linearized gravitational field with retarded potentials satisfies these conditions as do the asymptotic solutions for the Einstein field equations ${R}_{\mathrm{ab}}=0$, which have been constructed by Bondi and Newman. The significance of this result for the interpretation of the Bondi metric is discussed.
Ultraviolet light-induced responses of an mfd mutant of Escherichia coli B/r having a slow rate of dimer excision.

Abstract A mutant of Eschirichia coli B/r designated mfd has drastically reduced ability to exhibit “mutation frequency decline” (MFD) the irreversible loss of potential suppressor mutations which occurs when protein synthesis is briefly inhibited after irradiation with U.V. We have found that the initial rate of thymine dimer excision in the mfd mutant is only about one-third that of its mfd + parent strain after a UV dose of 400 erg/mm 2 . The yield of UV-induced Tyr + revertants is 4–10 times higher in the mfd strain than in the mfd + strain. This is comparable to the level of UV-mutability in the mfd + strain in the presence of caffeine, an inhibitor of dimer excision. UV-mutability, prophage induction and Weigle reactivation of irradiated λ phage occur to a greater extent at low UV doses (10–50 erg/mm 2 ) in the mfd strain compared to the mfd + strain. We propose that the slow excision repair in the mfd mutant results in a shift in the induction threshold for these UV-inducible functions toward lower UV doses.
Glioblastoma multiforme: State of the art and future therapeutics

Background: Glioblastoma multiforme (GBM) is the most common and lethal primary malignancy of the central nervous system (CNS). Despite the proven benefit of surgical resection and aggressive treatment with chemo- and radiotherapy, the prognosis remains very poor. Recent advances of our understanding of the biology and pathophysiology of GBM have allowed the development of a wide array of novel therapeutic approaches, which have been developed. These novel approaches include molecularly targeted therapies, immunotherapies, and gene therapy.
The Toyota Production System — Lessons for American Management

A management system which has been used in Japan's Toyota Motor Company for many years is described. The system is applicable to the assembled goods industry and is widely used in such circumstances in that country. It extends well beyond production and inventory control and incorporates a number of features of a decidedly Japanese nature. Dominant among these is just‐in‐time production which is examined at some length. Also described is Kanban, and several of its elements, which is an essential aspect of just‐in‐time production.
A Comparator Bridge Circuit

This paper describes a bridge circuit which was designed to perform a comparison between a temperature which is the controlled variable in a feedback control system, and a reference input or set point value. The feedback system was designed to control a certain heat transfer process.
Significance of p53 overexpression in urinary bladder transitional cell carcinoma in situ before and after bacillus Calmette-Guérin treatment

Abstract Objectives. Overexpression of p53, normally secondary to gene mutation, in invasive uroepithelial neoplasms (transitional cell carcinoma) and a high percentage of transitional cell carcinoma in situ (CIS) has been described; however, the role of p53 before and after bacillus Calmette-Guerin (BCG) treatment of CIS needs to be defined. Methods. Immunohistochemical reaction for p53 overexpression was performed on 12 patients with CIS before and after BCG treatment. Thirty cystectomy specimens with invasive TCC were also evaluated for the presence of CIS, hyperplasia, and dysplasia. Results. Twenty-three cases of CIS were identified. Approximately 90% of CIS cases (21 of 23) were positive for p53 overexpression, whereas transitional cell hyperplasia was uniformly negative. Less than 5% of the cells in morphologically dysplastic lesions were positively stained. Ten of 12 CIS patients displayed p53 overexpression before BCG treatment. After BCG treatment, 4 patients displayed residual CIS with p53 overexpression, and 8 patients showed no residual CIS or p53 overexpression. Three of the 4 patients with residual CIS and overexpression rapidly developed invasive transitional cell carcinoma requiring cystectomy. The 1 remaining patient was treated with a second course of BCG; further biopsies displayed the development of grade 1 papillary transitional cell carcinoma without invasion, and the patient is currently being followed. Conclusions. Our data suggest that follow-up biopsy procedures are essential in all patients with CIS treated with BCG. The biopsy specimens should be evaluated for p53 overexpression, because our data indicate that persistent p53 overexpression in uroepithelial lesions after BCG treatment is an ominous finding for probable tumor progression.
Reduction of Head Size in Advanced Hydrocephalus: A Case Report

On October 8, 1951, at the dawn of modern neurosurgical treatment of hydrocephalus and other cranial abnormalities, the parents of a child with advanced hydrocephalus posed the question: might the size of the head be reduced so as to allow sitting, standing, and perhaps walking? With the ingenious assistance of the child's father, who devised and made unique surgical instruments, the objectives were accomplished over a period of almost 2 years during which more than a dozen operations were carried out, including one of the first lumbar subarachnoid to peritoneum shunts using the Touhy needle instead of laminectomy. The operations conducted, the devices and tactics used, and the end results are described. No opportunity to treat another patient similarly has presented itself in the over 30-year interval since then, but I believe that the concept is valid and that success is realizable by others who may wish to use some of the techniques described, with appropriate modification.
Structural and chemical basis for glucosamine 6-phosphate binding and activation of the glmS ribozyme

The glmS ribozyme is the first naturally occurring catalytic RNA that relies on an exogenous, nonnucleotide cofactor for reactivity. From a biochemical perspective, the glmS ribozyme derived from Bacillus anthracis is the best characterized. However, much of the structural work to date has been done on a variant glmS ribozyme, derived from Thermoanaerobacter tengcongensis. Here we present structures of the B. anthracis glmS ribozyme in states before the activating sugar, glucosamine 6-phosphate (GlcN6P), has bound and after the reaction has occurred. These structures show an active site preorganized to bind GlcN6P that retains some affinity for the sugar even after cleavage of the RNA backbone. A structure of an inactive glmS ribozyme with a mutation distal from the ligand-binding pocket highlights a nucleotide critical to the reaction that does not affect GlcN6P binding. Structures of the glmS ribozyme bound to a naturally occurring inhibitor, glucose 6-phosphate (Glc6P), and a nonnatural activating sugar, mannosamine 6-phosphate (MaN6P), reveal a binding mode similar to that of GlcN6P. Kinetic analyses show a pH dependence of ligand binding that is consistent with titration of the cofactor's phosphate group and support a model in which the major determinant of activity is the sugar amine independent of its stereochemical presentation.
Thermofluids Considerations and the Dynamic Behavior of a Finger Seal Assembly

Finger seals represent a compliant seal configuration. What differentiates and makes them preferable to the brush seals is their potential hydrodynamic lifting capabilities, and thus their noncontacting nature. The fingers' compliance allows both axial and radial adjustment to rotor excursions without damage to the integrity of the seal. The work to be presented here concerns the mapping of the thermofluid and dynamic behavior of a repetitive section of the newly proposed design of a two-layer finger seal. The assembly contains four high-pressure and four low-pressure fingers arranged axially in a staggered configuration and subject to an axial pressure drop. The numerical three-dimensional temperature and pressure results were obtained using a customized Navier-Stokes–based commercial package, CFD-ACE+. The results were obtained in a parametric fashion where the high-pressure side, the speed of rotation, and the heat transfer coefficient are the controlling parameters; the gas compressibility and the vis...
Toward Covalently Linked Organic Networks: Model Studies and Connector Syntheses

A model 1-naphthoic acid bearing a peri-positioned cinnamic acid residue crystallizes as a closed H-bonded dimer. Irradiation of this crystalline solid provides an α-truxillate-type cyclobutane pho...
QUALITY ATTRIBUTES OF D'ANJOU PEARS AFTER DIFFERENT WAX DRYING TEMPERATURES AND REFRIGERATED STORAGE

Half-cooling times for hot (60°C) and cold (0°C) dried waxed pears in boxes, were identical and equal to 17 h. Waxed hot dried pears required an additional 21 h to equilibrate to holding room temperature. Waxing of pears modified the ripening pattern dependent upon whether the waxed pears were hot or cold dried. Waxed hot and cold dried pears exhibited lower external, but higher internal concentrations of CO2 than nonwaxed fruit. After prolonged storage waxed cold dried pears required more time to develop the characteristic ripe yellow color and retained firmness longer than either waxed hot dried or non-waxed pears. Waxed hot dried pears were slower to develop yellow color and retained firmness longer than nonwaxed pears. Pears waxed immediately after harvest or after 90 days of cold storage demonstrated increased ripening time compared to nonwaxed fruit.
Evaluation of a Disinfectant Wipe Intervention on Fomite-to-Finger Microbial Transfer

Inanimate surfaces, or fomites, can serve as routes of transmission of enteric and respiratory pathogens. No previous studies have evaluated the impact of surface disinfection on the level of pathogen transfer from fomites to fingers. Thus, the present study investigated the change in microbial transfer from contaminated fomites to fingers following disinfecting wipe use. Escherichia coli (10(8) to 10(9) CFU/ml), Staphylococcus aureus (10(9) CFU/ml), Bacillus thuringiensis spores (10(7) to 10(8) CFU/ml), and poliovirus 1 (10(8) PFU/ml) were seeded on ceramic tile, laminate, and granite in 10-μl drops and allowed to dry for 30 min at a relative humidity of 15 to 32%. The seeded fomites were treated with a disinfectant wipe and allowed to dry for an additional 10 min. Fomite-to-finger transfer trials were conducted to measure concentrations of transferred microorganisms on the fingers after the disinfectant wipe intervention. The mean log10 reduction of the test microorganisms on fomites by the disinfectant wipe treatment varied from 1.9 to 5.0, depending on the microorganism and the fomite. Microbial transfer from disinfectant-wipe-treated fomites was lower (up to <0.1% on average) than from nontreated surfaces (up to 36.3% on average, reported in our previous study) for all types of microorganisms and fomites. This is the first study quantifying microbial transfer from contaminated fomites to fingers after the use of disinfectant wipe intervention. The data generated in the present study can be used in quantitative microbial risk assessment models to predict the effect of disinfectant wipes in reducing microbial exposure.
Electrochemistry, principles to practice

Electrochemical Methods: Fundamentals and Applications. By A.J. Bard and L.R. Faulkner. Pp.718. ISBN hbk 0-471-05542-5; ISBN pbk 0-471-08753-X. (Wiley: 1981.) Hbk £21, $39.85; pbk £11.75, $21.70.
Readability: Blind Faith in Numbers?.

McConnell examines problems connected with measuring the readability of introductory economics textbooks and observes that an index of readability based on sentence length and the number of syllables per some given number of words may be deficient, misleading, and possibly counterproductive. In this connection, he observes that “virtually no work has been undertaken to determine whether the choice of textbook is a significant factor in determining student understanding and performance.” Research in this area might make it possible to substitute empirical evidence for what most instructors in their selection of a textbook attempt to intuit.
Venus and Adonis: Shakespeare's Critique of Spenser

IN writing Venus and Adonis, Shakespeare could not have ignored or been ignorant of The Faerie Queene. When Shakespeare published Venus and Adonis in 1593, The Shefheardes Calender (1581) had long since brought Spenser acclaim and renown; Sir Philip Sidney, for example, had singled it out for praise in The Defense of Poetry. In 1590, the first part of The Faerie Queene appeared and was enthusiastically received. Other writers—Nashe, Harrington, Daniel, Drayton, Lodge—heaped praise upon it: The printer's preface to a volume of Spenser's complaints published in 1591 describes the "favorable passage" The Faerie Queene won from the public.1 Recently, Donald Cheney has proposed that Shakespeare viewed "The Faerie Queene as his principal challenge as a poem to emulate and surpass" in Venus and Adonis.2 Because of the prominence of Spenser and his work, a version of the Venus and Adonis story published three years after Part I of the epic would not only admit Spenser's poem as a source, but also stand as a critical evaluation of the Garden of Adonis, the Garden's erotic philosophy, and Spenser's Ovidianism.
Improving the resilience of content distribution networks to large scale distributed denial of service attacks

Distributed Denial of Service (DDoS) attacks remain a daunting challenge for Internet service providers. Previous work on countering these attacks has focused primarily on attacks at a single server location and the associated network infrastructure. Increasingly, however, high-volume sites are served via content distribution networks (CDNs). In this paper, we propose two mechanisms to withstand and deter DDoS attacks on CDN-hosted Web sites and the CDN infrastructure. First, we present a novel CDN request routing algorithm which allows CDN proxies to effectively distinguish attacks from the requests from actual users. The proposed scheme, based on the keyed hash function, can significantly improve the resilience of CDNs to DDoS attacks. In particular, the resilience of a CDN, consisting of n proxies, becomes O(n^2) with the proposed approach, when compared to a site hosted by a single server. We present performance numbers from a controlled test environment to show that the proposed approach is effective. Second, we introduce novel site allocation algorithms based on the well-established theory on binary codes. The proposed allocation algorithm guarantees an upper bound on the level of service outage of a CDN-hosted site even when a DoS attack on another site on the same CDN has been successful. Together, our schemes significantly improve the resilience of the Web sites hosted by CDNs, and complement other work on countering DoS.
The ability of H-2+ and H-2− cell lines to induce or be lysed by Cytotoxic T cells

We have studied the T cell-mediated lysis of two C58 lymphoma lines: R1(TL+), which bears serologically detectable H-2k and TL1,2,3 antigens, and R1(TL−), an immunoselected variant which lacks these antigens. Unlike R1(TL+) cells, the variant cells are not sensitive to specific lysis by T cells directed against either H-2k or minor H antigens of C58 mice. An injection of R1(TL+) cells into allogeneic H-2-identical or H-2-different mice primes for an excellent secondary cytotoxic response in vitro to R1(TL+); but not to R1(TL−). Immunization in vivo and in vitro with R1(TL)−) leads to little or no priming or generation of cytotoxic T cells. Both cell lines, however, are sensitive to nonspecific lysis by cytotoxic cells in the presence of PHA or Con A, although even under these conditions, R1(TL+) is killed more effectively than is R1(TL−). We conclude that R1(TL−) does not express any form of H-2 antigen which can be detected by immunization or by sensitivity to cytotoxic T cells.
Assessing mitochondria biogenesis.

Mitochondria have their own DNA (mtDNA) and hence biogenesis of mitochondria requires a coordination of nuclear and mtDNA, both of which encode for mitochondria proteins. Our understanding of the molecular control of mitochondria biogenesis has increased in recent years, providing key signatures of the process. To determine whether or not a tissue or an organ of human or animal origin is undergoing mitochondria biogenesis, multiple parameters should be analyzed. First and foremost is visualization and measurement of mitochondria mass/volume in histological sections using fluorescent mitochondria dyes and light microscopy or transmission electron microscopy to yield quantitative results. To confirm or extend these types of analysis, biochemical markers of mitochondria biogenesis should also be included, including assessment of mtDNA copy number, steady-state levels of biogenesis-related transcription factors (e.g. mitochondria transcription factor A, mitochondrial transcription specificity factors, nuclear respiratory factors 1 and 2, and peroxisome proliferator activated receptor gamma coactivator-1-α), mtDNA-encoded transcripts and proteins, and rates of mitochondria translation. These techniques are described in isolation and in the context of transgenic and dietary animal models that have been used as tools to study the regulation of mitochondria biogenesis and its role in disease pathology.
Short- and medium-range structure of amorphous zircon from molecular dynamics simulations

We have obtained new insights into the structure of amorphous zircon using classical molecular dynamics simulations with a partial charge model. We present detailed structural characterizations of the simulated high and low density amorphous zircon and compare our results with available neutron diffraction, EXAFS, NMR and other experimental results. The results show that amorphization leads to polymerization of the silicon-oxygen network and the formation of regions rich in zirconium. The average n value of Qn species is 1.6-1.8. A considerable percentage of the oxygen ions (around 20%) have only zirconium in the first coordination shell (free oxygen) in amorphous zircon. The Zr-O bond length (around 2.10?) is shorter and the oxygen coordination number around zirconium smaller (6-7) than those in crystalline zircon, in good agreement with the EXAFS results. The total structure factors of simulated amorphous zircon also agree well with neutron diffraction results. We have examined the effects of the simulation cell size and relative density on the amorphous structure. The general features such as polymerization of silicon-oxygen network and the formation of clustered zirconium rich regions appear to be independent of system size and volume expansion in the range of 11 to 18%. Based on the obtained amorphousmore » zircon structure, experimentally observed lower chemical durability of amorphous zircon compared to its crystalline form can be explained by the existence of the silicon-oxygen networks and zirconium rich regions in amorphous zircon that provides diffusion channels and eases dissolution processes. Battelle operates PNNL for the USDOE« less
Field Dependence-Field Independence in 5- to 10-Year-Old Children

AbstractA final random sample of 160 Provo, Utah, elementary school children ages 5 to 10, was included in a balanced cell format to investigate the effects of school as reflective of socioeconomic level, age, sex, and intelligence on performance on the Children’s Embedded Figures Test (CEFT), a measure of Witkin’s field-dependence-independence hypothesis appropriate for use with young children. Results implied that (1) there may be differences on criterion performance according to relative social class; (2) age is the single best predictor of criterion performance, as significant differences proceeding from relative field-dependence to greater field-independence with increasing age were found; (3) there is a similar developmental pattern to increase in verbal intellectual power and increase in relative field-independence when all ages are considered together; (4) there were no significant similarities between field-dependence-independence and verbal intelligence within three of four specific ages investi...
Simultaneous Determination of Chromium(VI) and Chromium(III) by Flame Atomic Absorption Spectrometry with a Chelating Ion-Exchange Flow Injection System

Simultaneous Determination of Chromium(VI) and Chromium(III) by Flame Atomic Absorption Spectrometry with a Chelating Ion-Exchange Flow Injection System
Kinetics and Mechanism of the Formation of Palladium Bis(benzylamine) Complexes from Reaction of Benzylamine with Palladium Tri-o-tolylphosphine Mono(amine) Complexes

The kinetics of the conversion of the palladium mono(benzylamine) complex Pd[P(o-tol)3](p-C6H4CMe3)[H2NBn]Br (2) to the bis(benzylamine) complex Pd(p-C6H4CMe3)[H2NBn]2Br (3) established the second-...
Analysis of Performance and Efficiency of Conservation Voltage Optimization Considering Load Model Uncertainty

AbstractThis paper presents a novel method for evaluating the performance of conservation voltage optimization (CVO). The method investigates the load-to-voltage (LTV) sensitivity. A time-varying exponential load model is developed to represent the load’s dependence on voltage and other factors. The model parameters are estimated by applying the recursive least squares (RLS) algorithm. The effects of CVO can be assessed by using the estimated model parameters. The proposed RLS-based algorithm is validated by simulation tests and the Euclidian distance–based comparison method. Field test results also show the accuracy and effectiveness of the presented algorithm. To address the uncertainty and variability of the CVO performance, the Kolmogorov-Smirnov test is used to determine the distribution that represents the CVO effect of each substation. The proposed methodology can assist utilities in selecting target substations to implement voltage optimization.
Speed kills: cellular and molecular bases of methamphetamine-induced nerve terminal degeneration and neuronal apoptosis

Methamphetamine (METH) is a drug of abuse that has long been known to damage monoaminergic systems in the mammalian brain. Recent reports have provided conclusive evidence that METH can cause neuropathological changes in the rodent brain via apoptotic mechanisms akin to those reported in various models of neuronal death. The purpose of this review is to provide an interim account for a role of oxygen-based radicals and the participation of transcription factors and the involvement of cell death genes in METH-induced neurodegeneration. We discuss data suggesting the participation of endoplasmic reticulum and mitochondria-mediated activation of caspase-dependent and -independent cascades in the manifestation of METH-induced apoptosis. Studies that use more comprehensive approaches to gene expression profiling should allow us to draw more instructive molecular portraits of the complex plastic and degenerative effects of this drug.
Ultrastructural immunocytochemistry of nascent albumin topology: proposed cytosolic folding and membrane transit of the protein.

The relationship of nascent albumin and hepatocyte organelles was studied with the immunoperoxidase reaction in rats given various drugs to alter cellular albumin content. Colchicine was used to increase intracellular albumin. Cycloheximide inhibited synthesis but allowed nascent albumin to remain with its ribosome of origin. Puromycin also inhibited synthesis but released albumin from its ribosome. There was no difference in the appearance of attached ribosomes in hepatocytes from saline-injected rats and those given colchicine or cycloheximide. In these cases, membranes of the endoplasmic reticulum were consistently decorated with ribosomes positive for the presence of albumin antigenicity on their cytosolic surface. The cisternal and cytosolic compartments were negative. The situation after puromycin was different. Here the membranes appeared to be denuded of ribosomes and reaction product, indicative of albumin, was present only on the lumenal surface. To determine whether puromycin had caused the release of ribosomes, sections from puromycin-treated cells were stained nonspecifically with uranyl acetate. This showed that the normal amount of ribosomes was still bound but that they could not be seen when a probe specific only for albumin was used. It appears that nascent albumin can associate with its ribosome within the cytosol. Also, apparently after albumin passes through the membrane of the rough endoplasmic reticulum, it remains attached to its lumenal surface. A model incorporating cytosolic folding of albumin followed by its entropic membrane transit is presented.
On‐line ultrasonic measurements of methyl methacrylate polymerization for application to reactive extrusion

An ultrasonic measurement system was developed for monitoring the polymerization of methyl methacrylate (MMA) in a model batch reactor and a model twin screw extruder. Conversion of MMA polymerized in a home-made reaction chamber was compared with results obtained from a differential scanning calorimeter (DSC). The objective is to correlate ultrasonic velocity to extent of reaction based on the model experiments of poly(methyl methacrylate) in solution with MMA. This primary ultrasonic measurement system was applied to the on-line measurement of the extent of MMA polymerization in a model twin-screw extruder.
Anthropometric data for describing the kinematics of the human hand

The major goal of this investigation was to collect statistically-based anthropometry describing the kinematics of the human hand and to model this anthropometry as a function of external hand measurements, so that it may be predicted noninvasively. Joint centres were anatomically estimated as the centre of curvature of the head of the bone proximal to the given joint. Joint centres determined using Reuleaux's method for PIP and DIP were within 1.4 mm of this anatomical estimate. Models using bone length as the independent variable explain more than 97% of the variability in the anatomically estimated joint centre position along the mid-line of the bone. Models for estimating the lengths of the kinematic segments using external hand length as the independent variable account for between 49 and 99% of the variability in segment length. Models for estimating the axial location of the finger MCP and thumb CMC joints with respect to the distal wrist crease using external hand length as the independent variable account for between 82 and 96% of the variability in these locations. Models for estimating the radio-ulnar location of the finger MCP and thumb CMC joints with respect to the long axis of the third metacarpal using external hand breadth as the independent variable account for between 30 and 74% of the variability in these locations.
READING HABITS OF ELDERLY ADULTS: IMPLICATIONS FOR INSTRUCTION

Elderly adults, 18 male and 31 female, with a mean age of 67 years, participated in a study of their reading habits. Subjects responded to the Survey of Elderly Reading Attitudes instrument. Findings indicated that similarities and differences did occur among the reading habits of elderly adults. For example, most subjects felt that they had time to read; significantly more married than single subjects reported that they invest their funds in magazines and daily newspapers and proportionally more female than male subjects reported that they read advertisements without difficulty.
Atmospheric chemistry: Radical regeneration from isoprene

Significant quantities of the ozone and aerosol precursor isoprene are released into the atmosphere in densely forested regions of the world. Experimental observations suggest that the oxidation of isoprene in these pristine environments adds to the self-cleansing capacity of the atmosphere.
Supervision With Rose: A Tribute

A clinical supervisor can offer the fledgling clinician a rich education, including a foundation in clinical theory, guidance on clinical technique, and an awareness of the use of countertransference. Yet there may be no greater gift that a supervisor can bestow than bolstering the neophyte's self-confidence. In this brief essay, the author fondly remembers what his supervisor said to him that was so essential when he was at an early stage in his professional development.
Nature of periodontal diseases: Assessment and diagnosis

The assessment and diagnosis of periodontal diseases has become an active and controversial area of research which incorporates both new technologies and new concepts. Previous efforts have demonstrated the potential value of diagnostic testing in differentiating different diseases, in evaluating disease progression, and in monitoring the response to therapy. A few studies have even shown promise in predicting the response to therapy. Some of this work has incorporated proven diagnostic principles which allow a comparison between techniques. It is clear, however, that future work would benefit from an increased incorporation of these diagnostic principles and a recognition of the value of a sequential use of tests. Much work remains and many questions cannot be adequately answered at this time, but we should not lose sight of the great progress which has been made in the area of assessing and diagnosing periodontal diseases.