cssi/SciSciGPT-SciSciNet huggingface dataset:
Carcinoma of the thyroid gland: a statistical study of 390 patients.

At the University of California Hospitals a study has been made of the 390 patients with thyroid carcinoma who were observed in the 40-year period between 1920 and 1959. Thyroid carcinoma was found in both lobes at the time of the “initial operation” in 19 per cent of these patients, and regional lymph node metastases were reported at one time or another in 42 per cent. These data warrant a more radical surgical approach to thyroid carcinoma. During the past fifteen years, therefore, the majority of such patients at the University of California have been treated by more radical forms of thyroidectomy. The rate of local recurrence in the thyroid area was significantly lower in patients treated by total thyroidectomy than in those treated only by unilateral subtotal lobectomy. Cumulative survival rates were higher for patients with papillary carcinoma than for those with follicular carcinoma, and the survival rates for patients with papillary or follicular carcinoma were higher than for those with anaplasti...
The Experiences of Students with Learning Disabilities in a Higher Education Virtual Campus.

Institutions of higher education are increasingly asking students to use the online environment, or virtual campus, when carrying out business related to college life. In this paper, we report findings from a study conducted to learn more about the experiences of college students with learning disabilities as they interacted with this virtual campus. Sixteen college students with documented learning disabilities were observed and interviewed while completing eight tasks in a virtual campus environment. Tasks were chosen from those typically performed by college students and included such items as locating the email address of an instructor, locating a journal article in the library’s online database, and identifying the textbook for a course on the bookstore webpage. Findings indicate that these participants were both successful and not successful in task completion within the virtual campus. Factors that impacted performance included features of the virtual campus and participants’ implementation of cognitive and behavioral strategies.
Intraglottal pressure distribution computed from empirical velocity data in canine larynx

Intraglottal velocity measurements were taken using particle image velocimetry and the corresponding estimates for the intraglottal pressure were computed using the pressure Poisson equation. Results from five canine larynges showed that when the flow separated from the divergent glottal walls during closing, the vortices that were formed in the separated region of the glottis created negative pressure near the superior aspect of the folds. The magnitude of the negative pressure was directly proportional to the subglottal pressure. At low subglottal pressure, negative pressures at the superior edge were not observed when the divergence angle of the wall was minimal and the glottal flow did not separate from the wall.
Interrelationship of Dietary Vitamin D3 with Zinc and Iron in Young Turkeys

Abstract Three experiments were conducted with Large White turkeys to four weeks of age. The interrelationship of zinc and vitamin D3 was studied in two experiments. Iron and vitamin D3 were involved in one experiment. One group of ten male and one group of ten female poults were randomly assigned to each treatment within an experiment. All experiments involved a factorial arrangement of two dietary variables, D3 and either zinc or iron. For example, all possible combinations of four zinc levels; 31, 46, 76 and 106 p.p.m. and three vitamin D3 levels; 600, 1200, and 3600 I.C. units/kg. were fed in the second zinc experiment. Significant (P
Negatively curved graphitic sheet model of amorphous carbon.

A computational method has been developed for generating graphitic carbon structures on an arbitrary smooth surface and with a given number of carbon rings. Using both periodic and random surfaces for constraint, many extended graphitic carbon structures have been generated. The energy relative to graphite and the bulk elastic properties have been calculated. Like their periodic counterparts, the random structures are found to be exceptionally stable. Their radial distribution functions match closely those of films of amorphous carbon grown on NaCl substrates from sublimated graphite.
Statistical evaluation of econometric air travel demand models

To use econometric air travel demand models properly and effectively, it is essential to understand the underlying assumptions which lead to the estimation procedure, and to subject these assumptions to rigorous scrutiny before any such models can be used either to forecast air traffic or to assess the impact of policy changes dictated by the airline, the aircraft manufacturer, or the federal government. This paper evaluates the impact of violation of the following assumptions in the regression model: 1) mean of the stochastic disturbance term is zero; 2) variance-covariance matrix of the disturbance vectors is diagonal with constant variance; 3) the disturbance terms are distributed normally; 4) values of explanatory variables are nonstochastic; and 5) matrix X is of full column rank. Methods of detecting the violation of these assumptions, as well as methods of eliminating the severity of these problems, are presented. The paper also contains extensions of the common statistical tests used to evaluate the appropriateness of such models. While at first sight the statistical evaluation procedures discussed here may appear overly complex, the aerospace anlayst is reminded of the multimillion-dollar investments which are sometimes made based on the results of econometric models judged solely on the high R2 values. I. Introduction S INCE econometric models have become common tools for forecasting demand for air transportation, it is important to examine the statistical procedures commonly used in the estimation of parameters in such models. To apply the models properly and effectively, it is essential not only to understand the underlying assumptions and their implications, which lead to the estimation procedure, but also to subject these assumptions to rigorous scrutiny. With careful analysis the model can be used either to forecast air traffic or to assess the impact of policy changes dictated by airline management and the Civil Aeronautics Board. The purpose of this paper is first to discuss the more important theoretical assumptions in determining the best estimators of the unknown parameters of air travel demand models, and second, to present some formal statistical tests to examine the appropriateness of such models. The emphasis is focused on the statistical evaluation of the common econometric methods and the confidence which can be placed in models which often influence large investments in either fleet acquisition or market planning. Often the decision maker is not statistically oriented, and can make the commitment of substantial corporate resources on the results of a model which may be statistically invalid, or at least inappropriate. This discussion is theoretical, since the currently operating air traffic forecasting models have not been published in sufficient detail to perform the formal statistical evaluation discussed in this paper.
A hybrid algorithm for predicting chip form/chip breakability in machining

Abstract Prediction of chip breakability for a wide range of machining conditions is a difficult task. Currently available predictive machining theories are not suitable for use in the shop floor environment. The methodology presented in this paper provides a new and viable means to predict chip breakability and chip shapes/sizes in machining process planning systems. Due to the extreme difficulty involved in developing a numerical model for predicting chip breakability for a wide range of machining conditions, including work materials, tool geometry, chip-breakers and cutting conditions, this paper presents a hybrid algorithm-based model to characterize various chip shapes and sizes, and to quantify the chip form/chip breakability based on a chip control reference database developed through a set of systematic machining experiments. The chip form and chip breakability could then be predicted with reasonable accuracy for a given set of machining conditions using this new algorithm in conjunction with the chip control reference database.
Carrington Maps of the Upper Photosphere

We have used images of the Sun's disk, obtained in the 6767 A continuum with the Michelson Doppler Interferometer (MDI) on the Solar and Heliospheric Observatory (SOHO), to make Carrington maps of the upper photosphere during the years 1996-2005. Each map is constructed from observations near the limb where the continuum radiation originates relatively high in the photosphere and faculae have their greatest visibility. Consequently, the Carrington maps resemble spectroheliograms in temperature-sensitive photospheric lines and show the global distribution of faculae and all but the smallest sunspots (which are obscured by overlying faculae). A time-lapse sequence of the combined east-limb and west-limb maps shows the emergence of active regions and the evolution of large-scale patterns of faculae with an average temporal resolution of 14 days during the sunspot cycle. Also, a longitudinally averaged butterfly diagram of these maps shows that in each hemisphere there is a facula-free zone separating the old-cycle polar field from trailing-polarity flux that is migrating poleward from the sunspot belts. These facula-free zones coincide with the neutral zones of the axisymmetric component of photospheric magnetic field and their arrival at the poles in 2001 marks the reversal of the polar fields. We think that this mapmaking technique can be applied to white-light images obtained daily at the Mount Wilson Observatory since 1905 and that the resulting Carrington maps will provide details about the polar-field reversal process during past sunspot cycles when high-quality magnetograms were unavailable.
In vitro incorporation of amino-acids into the contractile protein of human blood platelets.

BLOOD platelets contain a considerable concentration of protein of which about 21 per cent can be accounted for by fibrinogen, serum albumin and a glycogen–globulin complex1. Most of the protein of the platelet consists of the specific contractile protein, thrombosthenin2,3, and other uncharacterized protein1. The origin of platelet proteins has not been established, but it is likely that albumin and fibrinogen originate in plasma, although no other plasma proteins have been detected in platelets1. Platelets are formed by fragmentation of the megakaryocyte4–6 and do not contain a nucleus. It is possible that the contractile as well as other proteins are already present in the cytoplasm during the maturation of the megakaryocyte. It is also possible that certain proteins are synthesized by the platelet in which ribosomes have been observed7. This communication reports the incorporation of amino-acids labelled with carbon-14 into the contractile protein of human blood platelets.
Analysis of Aluminum by Inductively Coupled Plasma-Atomic Emission Spectroscopy

Inductively coupled plasma-atomic emission spectroscopy (ICP-AES) is applied in the determination of 21 elements in primary, refined, and alloy aluminum. Rapid and reliable sample preparation procedures are developed. Spectral lines are selected after examination of experimental wavelength scans at each analyte wavelength. The limits of detection, background equivalent concentration, and analytical figures of merit are determined. For high silicon-containing aluminum, HF solutions were analyzed by employing an inert nebulizer utilizing polytetrafluoroethylene (PTFE) capillary tubes, a PTFE spray chamber, and an ICP torch with a graphite injector tube.
Transmembrane allosteric coupling of the gates in a potassium channel.

It has been hypothesized that transmembrane allostery is the basis for inactivation of the potassium channel KcsA: opening the intracellular gate is spontaneously followed by ion expulsion at the extracellular selectivity filter. This suggests a corollary: following ion expulsion at neutral pH, a spontaneous global conformation change of the transmembrane helices, similar to the motion involved in opening, is expected. Consequently, both the low potassium state and the low pH state of the system could provide useful models for the inactivated state. Unique NMR studies of full-length KcsA in hydrated bilayers provide strong evidence for such a mutual coupling across the bilayer: namely, upon removing ambient potassium ions, changes are seen in the NMR shifts of carboxylates E118 and E120 in the pH gate in the hinges of the inner transmembrane helix (98–103), and in the selectivity filter, all of which resemble changes seen upon acid-induced opening and inhibition and suggest that ion release can trigger channel helix opening.
Metabolic regulation of steroidogenesis in isolated adrenal cells of the rat. ACTH regulation of cGMP and cAMP levels and steroidogenesis.

The model of isolated adrenal cell system [l-3] permits direct studies of ACTH’ action on isolated target tissue cells. These cells a) respond to microunit amounts of ACTH [l] in the synthesis of corticosterone from endogenous precursors, b) have undetectable levels of phosphodiesterase activity [4] and c) can convert the exogenously added precursors, (2OS)-20hydroxycholesterol, pregnenolone, progesterone and deoxycorticosterone to corticosterone [5-81. The levels of CAMP produced in response to ACTH have been measured in this preparation [9] but the nucleotide levels and corticosterone production lack a perfect correlation [IO]. It is thus possible that ACTH control of steroidogenesis is not entirely due to its presumed second messenger CAMP [S] . The present studies provide evidence that ACTH control of steroidogenesis may be du: to both cyclic nucleotides, CAMP and cGMP. Preliminary results of these observations have been presented elsewhere [ 11,121.
On the Threshold: Youth as Arbiters of Urban Space in Early Modern France

Recent historical interest in early modern urban space has largely ignored the place of children and youth in the city. This study uses criminal records from seventeenth- and eighteenth-century Dijon, France to determine the triggers, locations, and contexts for disputes involving young people. The essay demonstrates that while young people articulated a field of honor similar to that of established adults in their neighbourhoods, their liminal status encouraged them to refine their concepts of honor and identity in urban areas not controlled by adults. City walls and night-time streets, for example, were common spaces where youth experimented with their identities. While historians may anticipate that the youths’ activities occurred primarily within peer groups, this essay argues that the fragile identities of young men and women were strongly rooted in their households. The strategies and tactics the youth employed within the city landscape were informed by their gender and by their transitional life-stage between dependence and autonomy.
Helicobacter pylori: rational management options

Abstract In the treatment of Helicobacter pylori -associated peptic ulcer disease, the complexity (ie, frequency and duration) of drug administration, the presence or development of bacterial antibiotic resistance, and the occurrence of side effects influence patient compliance and eradication rates, which consequently affect the costs of treatment regimens. The National Institutes of Health Consensus Conference and 1997 Digestive Health Initiative Update Conference have recommended that all patients with gastric or duodenal ulcer and H pylori infection, whether on first presentation or recurrence, be treated with antimicrobials. However, H pylori resistance to antimicrobials, specifically to nitroimidazole compounds, has resulted in varied and decreasing success rates of treatment regimens. Comparing the efficacy, safety, and costs of current treatment strategies for the eradication of H pylori , a combination triple therapy with a proton pump inhibitor, amoxicillin, and clarithromycin is recommended as an effective alternative to standard bismuth-based triple therapy. When compared with other therapies, these offer more rapid symptomatic relief, improved tolerability, increased compliance and efficacy, and moderate costs.
Neurosteroids enhance bandpass filter characteristics of the rat Schaffer collateral-to-CA1 synapse.

Neurosteroids are important modulators of synaptic activity in the mammalian central nervous system. We have shown previously that the neurosteroid, pregnenolone sulfate (PREGS) enhances paired-pulse facilitation at the Schaffer collateral-to-CA1 synapse in rat hippocampal slices. Here we show that PREGS enhances the facilitation of postsynaptic potentials (PSPs) during a 300 ms train of repetitive stimuli at frequencies between10 and 50 Hz. At higher or lower frequencies, however, PREGS does not affect the PSPs produced by repetitive stimuli. This enhancement of the bandpass filtering characteristic of a central synapse by a naturally occurring neurosteroid could selectively influence transmission at bursting or other highly active synapses.
Microtubule sliding in cilia of the rabbit trachea and oviduct

Evidence for active sliding of microtubules during ciliary activity has been demonstrated in a number of organisms: sea urchin sperm flagella, protozoan cilia, and mollusc gill cilia. Although there is evidence that active sliding also occurs in mammalian sperm flagella, there is little or no information on whether active sliding of microtubules also occurs in the short (5-micron) cilia of the mammalian trachea or oviduct. Since these cilia are important in tracheobronchial clearance and ovum transport, respectively, it has been important to demonstrate that microtubule sliding is also involved in the activity of somatic cilia. Ciliated apical portions (cortices) and cilia were isolated from rabbit trachea and oviduct, using Triton X-100 to demembranate the cilia. Most of the ciliated cortices reactivated upon addition of ATP, whereas isolated cilia reactivated to a lesser extent. When preparations of cilia were digested with trypsin before or after ATP addition, disintegration of axonemal doublets occurred with about the same frequency as reactivation. These events were recorded using Nomarski optics and dark-field microscopy. When isolated cilia which had been digested by trypsin and exposed to ATP were also prepared for electron microscopy by negative staining, telescoping of doublet microtubules from axonemes could be shown. These results demonstrate that mammalian somatic ciliary doublet microtubules actively slide in a manner similar to that described for invertebrate cilia.
Field-Static Corrections For Shallow Reflection Surveys Using the Generalized Reciprocal Method

Stat ic correct ion is an essent ia l s tep in ref lec t ion se ismic process ing. I t removes t h e t r a v e l t i m e e f f e c t o f n e a r surface veloci ty var ia t ion on ref lect ions originating at depth. Because small time s h i f t s e q u a t e t o l a r g e p h a s e s h i f t s f o r h i g h f r e q u e n c y d a t a , t h i s c o r r e c t i o n i s especially important for shallow, highresolution surveys. CMP surveys provide a great r e d u n d a n c y i n f i r s t a r r i v a l s a t e a c h geophone location. This s tudy uses the G e n e r a l i z e d R e c i p r o c a l M e t h o d ( G R M ) (Palmer, 1986) to transform these firsta r r i v a l t i m e s i n t o r e f r a c t o r d e p t h a n d velocity. Small geophone spacing insures continuously varying depth and veloci ty c a l c u l a t i o n a l o n g t h e r e f r a c t o r . U s e o f the median avoids the influence of erratic values and combines multiple values at each geophone into a single, reliable number. The direct arrival from the top of the weathered layer usually is not captured on reflection data because the near-offset trace lies beyond the crossover distance. Consequently, a means of establishing accurate veloci ty v a r i a t i o n i n the weathered layer is needed. This study shows how the assumption of reasonable refractor topography allows weathered layer velocity variation to be established from GRM-derived refractor depths Detailed field-static correction is c a l c u l a t e d f o r a h i g h r e s o l u t i o n survey from southern Kansas. A variation of 5 ms in static correction occurs across 250 m, and a shift of up to 1 ms occurs over 60 m.
Connectionist models of recognition memory: Constraints imposed by learning and forgetting functions.

Multilayer connectionist models of memory based on the encoder model using the backpropagation learning rule are evaluated. The models are applied to standard recognition memory procedures in which items are studied sequentially and then tested for retention. Sequential learning in these models leads to 2 major problems. First, well-learned information is forgotten rapidly as new information is learned. Second, discrimination between studied items and new items either decreases or is nonmonotonic as a function of learning. To address these problems, manipulations of the network within the multilayer model and several variants of the multilayer model were examined, including a model with prelearned memory and a context model, but none solved the problems. The problems discussed provide limitations on connectionist models applied to human memory and in tasks where information to be learned is not all available during learning. The first stage of the connectionist revolution in psychology is reaching maturity and perhaps drawing to an end. This stage has been concerned with the exploration of classes of models, and the criteria that have been used to evaluate the success of an application have been necessarily loose. In the early stages of development of a new approach, lax acceptability criteria are appropriate because of the large range of models to be examined. However, there comes a second stage when the models serve as competitors to existing models developed within other theoretical frameworks, and they have to be competitively evaluated according to more stringent criteria. A few notable connectionist models have reached these standards, whereas others have not. The second stage of development also requires that the connectionist models be evaluated in areas where their potential for success is not immediately obvious. One such area is recognition memory. The work presented in this article evaluates several variants of the multilayer connectionist model as accounts of empirical results in this area. I mainly discuss multilayer models using the error-correcting backpropagation algorithm and do not address other architectures such as adaptive resonance schemes (Carpenter & Grossberg, 1987). Before launching into the modeling of recognition memory, I need to specify the aims and rules under which this project was carried out. This is important in a new area of inquiry because there are many divergent views about what needs to be
Perfluorooctyl and perfluorobutyl bonded alumina stationary phases for high performance liquid chromatography

Abstract The preparation and properties of perfluorooctylalumina (PFOA) and perfluorobutylalumina (PFBA) high performance liquid chromatographic stationary phases have been investigated. The PFOA phase was produced by chemisorption of perfluorooctanoic acid onto the surface of alumina. The PFBA phase was produced by a similar adsorption of perfluorobutylphosphonic acid onto alumina. Both phases exhibit reverse phase liquid chromatographic properties. Elemental analyses of these materials indicated that alkyl group surface coverage of the PFBA phase is higher than that of the PFOA phase. In contrast, retention of solutes on the PFBA phase is lower than that of PFOA. Isocratic capacity factors of over 20 compounds on the PFOA and PFBA phases were determined and compared with those obtained on octadecylalumina (ODA) and octadecylsilica (ODS) phases. In contrast to the greater retention of phenols than other compounds that was evident on the unfluorinated ODA phase, the retention of phenols on the PFOA and PF...
The influence of grain size and grain size distribution on methods for estimating paleostresses from twinning in carbonates

Abstract This study examines the relative differential stresses around a minor thrust fault within the Mountain City window, Tennessee, U.S.A. The fault zone developed within dolomite rocks and deformation took place by twinning, fracturing, pressure solution and the development of fine-grained deformation zones. Grain-size reduction is observed from undeformed wall rock to the center of the fault zone, and occurred by dynamic recrystallization. Methods to determine paleostresses in naturally deformed rocks from twinning assume a single, coaxial, strain-inducing event. The recrystallization within the center of the fault zone removed the effects of earlier deformation, so that the twinning more closely reflects a single, coaxial deformation event late in the fault history. Two methods were used to estimate the relative differential stresses across the fault zone and the results show opposite trends towards the center of the fault zone. The different results may be partially explained by the influence of grain size, as only one of these methods considers the influence of grain size. In addition, the grainsize data from this fault zone demonstrate that the tendency for a grain-size class to be twinned depends on the grain size distribution. The grain size distribution may result in grain-to-grain stress concentrations that induce twinning. Thus, grain size distribution should also be considered to achieve more accurate estimates of paleostresses.
Sleep-waking discharge of neurons in the posterior lateral hypothalamic area of cats

Damage to the posterior hypothalamic area produces a syndrome of EEG synchrony and behavioral somnolence. Cells of a recently described projection system within the posterior lateral hypothalamic area (PLHa) are potential candidates for mediating this area's influences on EEG and behavioral arousal. We examined PLHa neuronal activity during sleep and wakefulness in freely moving cats, identifying projection neurons by antidromic activation from stimulation sites in the external capsule, anterior cingulate bundle, or mesencephalic reticular formation. Orthodromic response evoked from these sites were also investigated. Twenty-two cells were found to send axons outside the PLHa; 9 with ascending projections and 13 with descending projections. Projection cells were found to discharge phasically in relation to waking movements. Most seemed to be related to complex head movements, although specific movement correlates were difficult to ascertain. Discharge rates during periods of waking immobility were similar to those occurring during slow-wave sleep. Rates during phasic REM sleep were generally similar to peak waking rates. Cells with ascending and descending projections displayed similar discharge profiles, although the former had somewhat higher rates in all conditions. Seventy-four cells were orthodromically driven from external capsule or anterior cingulate bundle. Responses evoked from these two sites were similar; an initial brief period of excitation, followed by a sustained (mean greater than 100 msec) episode of discharge suppression. Twenty-four cells exhibited orthodromic excitation from the mesencephalic reticular formation, but the duration of the subsequent discharge suppression was comparatively brief (mean less than 30 msec). With few exceptions, the discharge correlates of orthodromically driven cells were identical to those described above for identified projection neurons. These results do not support a role for neurons within the PLHa in the control of tonic EEG arousal. They are consistent with a possible involvement in either motor function, or phasic movement-related aspects of EEG activation.
Approximation of Tail Probabilities by Means of the B n -Transformation

Abstract A general method for approximating tail probabilities is described and exemplified. The method has the advantage of being quite straightforward and easy to apply. The behavior of the approximations resulting from the proposed procedure is investigated for gamma, beta, and normal distributions.
Mining high dimensional data for classifier knowledge

We present in this paper the problem of discovering sets of attribute-value pairs in high dimensional data sets that are of interest not because of co-occurrence alone, but due to their value in serving as cores for potential classifiers of clusters. We present our algorithm in the context of a gene-expression dataset. Gene expression data, in most situations, is insufficient for clustering algorithms and any statistical inference because for 6000+ genes, typically only 10s and at most 100s of data points become available. It is difficult to use statistical techniques to design a classifier for such immensely under-specified data. The observed data, though statistically, insufficient contains some information about the domain. Our goal is to discover as much information about all potential classifiers as possible from the data and then summarize this knowledge. This summarization provides insights into the composition of potential classifiers. We present here algorithms and methods for mining a high dimensional data set, exemplified by a gene expression data set, for mining such information.
Breaking the energy barrier in fault-tolerant caches for multicore systems

Balancing cache energy efficiency and reliability is a major challenge for future multicore system design. Supply voltage reduction is an effective tool to minimize cache energy consumption, usually at the expense of increased number of errors. To achieve substantial energy reduction without degrading reliability, we propose an adaptive fault-tolerant cache architecture, which provides appropriate error control for each cache line based on the number of faulty cells detected at reduced supply voltages. Our experiments show that the proposed approach can improve energy efficiency by more than 25% and energy-execution time product by over 10%, while improving reliability up to 4X using Mean-Error-To-Failure (METF) metric, compared to the next-best solution at the cost of 0.08% storage overhead.
Managing Disruption Risks in Supply Chains

There are two broad categories of risk affecting supply chain design and management: (1) risks arising from the problems of coordinating supply and demand, and (2) risks arising from disruptions to normal activities. This paper is concerned with the second category of risks, which may arise from natural disasters, from strikes and economic disruptions, and from acts of purposeful agents, including terrorists. The paper provides a conceptual framework that reflects the joint activities of risk assessment and risk mitigation that are fundamental to disruption risk management in supply chains. We then consider empirical results from a rich data set covering the period 1995–2000 on accidents in the U. S. Chemical Industry. Based on these results and other literature, we discuss the implications for the design of management systems intended to cope with supply chain disruption risks.
A non-classical Kirchhoff plate model incorporating microstructure, surface energy and foundation effects

A new non-classical Kirchhoff plate model is developed using a modified couple stress theory, a surface elasticity theory and a two-parameter elastic foundation model. A variational formulation based on Hamilton’s principle is employed, which leads to the simultaneous determination of the equations of motion and the complete boundary conditions and provides a unified treatment of the microstructure, surface energy and foundation effects. The new plate model contains a material length scale parameter to account for the microstructure effect, three surface elastic constants to describe the surface energy effect, and two foundation moduli to represent the foundation effect. The current non-classical plate model reduces to its classical elasticity-based counterpart when the microstructure, surface energy and foundation effects are all suppressed. In addition, the newly developed plate model includes the models considering the microstructure dependence or the surface energy effect or the foundation influence alone as special cases and recovers the Bernoulli–Euler beam model incorporating the microstructure, surface energy and foundation effects. To illustrate the new model, the static bending and free vibration problems of a simply supported rectangular plate are analytically solved by directly applying the general formulas derived. For the static bending problem, the numerical results reveal that the deflection of the simply supported plate with or without the elastic foundation predicted by the current model is smaller than that predicted by the classical model. Also, it is observed that the difference in the deflection predicted by the new and classical plate models is very large when the plate thickness is sufficiently small, but it is diminishing with the increase of the plate thickness. For the free vibration problem, it is found that the natural frequency predicted by the new plate model with or without the elastic foundation is higher than that predicted by the classical plate model, and the difference is significant for very thin plates. These predicted trends of the size effect at the micron scale agree with those observed experimentally. In addition, it is shown both analytically and numerically that the presence of the elastic foundation reduces the plate deflection and increases the plate natural frequency, as expected.
An investigation into factors affecting the precision of CT radiation dose profile width measurements using radiochromic films

Purpose: To investigate the impact of x-ray beam energy, exposure intensity, and flat-bed scanner uniformity and spatial resolution on the precision of computed tomography (CT) beam width measurements using Gafchromic XR-QA2 film and an off-the-shelf document scanner. Methods: Small strips of Gafchromic film were placed at isocenter in a CT scanner and exposed at various x-ray beam energies (80–140 kVp), exposure levels (50–400 mA s), and nominal beam widths (1.25, 5, and 10 mm). The films were scanned in reflection mode on a Ricoh MP3501 flat-bed document scanner using several spatial resolution settings (100 to 400 dpi) and at different locations on the scanner bed. Reflection measurements were captured in digital image files and radiation dose profiles generated by converting the image pixel values to air kerma through film calibration. Beam widths were characterized by full width at half maximum (FWHM) and full width at tenth maximum (FWTM) of dose profiles. Dependences of these parameters on the above factors were quantified in percentage change from the baselines. Results: The uncertainties in both FWHM and FWTM caused by varying beam energy, exposure level, and scanner uniformity were all within 4.5% and 7.6%, respectively. Increasing scanner spatial resolution significantly increased the uncertainty in both FWHM and FWTM, with FWTM affected by almost 8 times more than FWHM (48.7% vs 6.5%). When uncalibrated dose profiles were used, FWHM and FWTM were over-estimated by 11.6% and 7.6%, respectively. Narrower beam width appeared more sensitive to the film calibration than the wider ones (R 2 = 0.68 and 0.85 for FWHM and FWTM, respectively). The global and maximum local background variations of the document scanner were 1.2%. The intrinsic film nonuniformity for an unexposed film was 0.3%. Conclusions: Measurement of CT beam widths using Gafchromic XR-QA2 films is robust against x-ray energy, exposure level, and scanner uniformity. With proper film calibration and scanner resolution setting, it can provide adequate precision for meeting ACR and manufacturer’s tolerances for the measurement of CT dose profiles.
Vasopressin regulation of renal sodium excretion

Vasopressin promotes renal water reabsorption decreasing excretion of free water to dilute plasma and lower serum osmolality. We have good understanding of the causes, mechanisms and consequences of this vasopressin-dependent renal water movement. In comparison, vasopressin actions on renal electrolytes including sodium excretion and its consequences have been less well understood. This is so for investigation and discussions of the renal actions of vasopressin are framed primarily around water metabolism rather than any direct effect on salt handling. The fact that water moves in biological systems, to include the mammalian kidney, only by osmosis passively down its concentration gradient is implicit in such discussion but often not overtly addressed. This can cause confusion. Moreover, although vasopressin action on renal sodium excretion via the V2 receptor is critical to water transport, it is masked easily being situational—for instance, dependent on hydration state. It is now clear that an increase in sodium reabsorption along the distal nephron (CNT + CD) mediated by activation of the epithelial Na + channel (ENaC) by vasopressin makes an important contribution to maintenance of the axial corticomedullary osmotic gradient necessary for maximal water reabsorption. Thus, we need to modify slightly our understanding of vasopressin and its renal actions to include the idea that while vasopressin decreases free water excretion to dilute plasma, it does this, in part, by promoting sodium reabsorption and consequently decreasing sodium excretion via ENaC activated along the distal nephron.
A molecular theory of the fracture toughness of low molecular weight polymers

Recent experiments by Robertson show that the fracture toughness GIC of glassy polystyrene PS does not decrease to the ideal brittle value 2γ (where γ is the surface energy for PS) at molecular weights Mw below Mc the entanglement molecular weight. Instead GIC is more than an order of magnitude above 2γ at Mc and decreases slowly below Mc. It is postulated that a small craze exists at the crack tip in such low molecular weight glassy polymers. However, since entanglements do not occur single molecules must span this craze; if they do not the craze becomes unstable and the crack advances. Under these conditions a critical craze surface displacement exists and GC can be computed to be GIC=Sc(λ−1) 〈R2〉1/2, where λ and Sc are the craze fibril extension ratio and craze surface drawing stress observed in high molecular weight crazes (both quantities should be only weak functions of Mw) and 〈R2〉1/2 is the root mean square end-to-end distance of the PS molecule in the glass from neutron scattering measurements. The fracture toughness is predicted to decrease as Mw1/2; this prediction and the absolute magnitude of GIC are in excellent agreement with experiment.
Diffusion in concentrated polystyrene solutions

The wedge interferometer technique was used to measure the diffusion coefficients for concentrated solutions of polystyrene. A wide range of molecular weights, all monodisperse except for one, and 14 solvents were studied. Reproducibility of the data was demonstrated in the concentrated region, and good agreement with the sparse literature was observed. The experimental results are discussed and analyzed in terms of current knowledge and theories. In the concentrated region, the solvent type plays a significant role in determining the diffusion coefficient. Its effect cannot be explained simply in terms of hydrodynamics nor the molecular structure of the solvent. In cyclohexanone the diffusion coefficient was found to increase with polymer molecular weight up to 100,000 and to become independent thereafter.
A Companion to African American History

Alton Hornsby, Jr (ed.) A Companion to African American History Oxford: Blackwell, 2008, 564 pp., £24.99 pb. (ISBN 978-0-6312-3066-3) A Companion to African American History is an impressive collec...
Frequency Response of Phase Locked Loops

This paper is concerned with the design of the phase locked loop (PLL) to be used as an FM demodulator. With the introduction of the PLL IC and the trend of designing inductorless circuits, there has been much interest in the PLL FM demodulator.1'2 The discussion in this paper concentrates on the steady state response of the PLL to sinusoidally frequency modulated signals;. therefore, the analytic and experimental results are shown in the form of frequency response diagrams.
Validation of a relationship between statolith size and age of larval Great Lakes sea lamprey (Petromyzon marinus)

Sea lampreys (Petromyzon marinus) are parasitic pests in the Great Lakes that have negatively affected game fish populations. Accurate aging of pest species such as sea lampreys can provide estimates of growth and mortality rates, which can direct control efforts. Because growth of larval sea lampreys is both slow and variable, determining age based solely on visual assessments of length-frequency distributions is subject to considerable uncertainty. Otoliths have been used to estimate age in teleosts through annuli counts and otolith size metrics. Lampreys do not have otoliths, having instead an analogous structure called a statolith. Determining age based on statolith annuli counts has been found to be imprecise and inaccurate. Therefore, we evaluated whether statolith size was correlated with ammocoete age using known-age populations of ammocoetes from two Great Lakes streams with contrasting physical conditions that affect larval sea lamprey growth. A morphometric system was used to measure length, width, and height of statoliths from these known-age populations. Statolith width was found to be the measurement that best distinguished the age-classes within the populations. A likelihood-based statistical model was used to assess ammocoete population age composition. Even though statolith width was clearly associated with age, combining statolith width data and length-frequency did not improve estimates of proportions at age relative to those estimated using only length-frequency information.
Galvanomagnetic properties of Ag/M (M Fe, Ni, Co) layered metallic films

Abstract Magnetoresistance and the Hall Effect have been measured at 4.2, 78, and 300 K for a series of layered metallic films produced by sputtering. The sample periodicity Λ lay between 11 A and 400 A. The field and temperature dependencies of the magnetization were measured on a SQUID magnetometer. From the anomalous Hall Effect and magnetization measurements, surface anisotropy parameters are calculated. The magnetoresistance as a function of field direction is sharply peaked when the field is perpendicular to the sample. The associated anisotropy is Λ dependent.
DEVELOPING PERCEPTIONS OF TEMPERAMENT AND THEIR CHILDREN TO MOTHER AND INFANT BEHAVIOR

Controversies about temperamental assessments raise questions about whether questionnaires, which assess parental perceptions of temperament, validly measure within-child characteristics. Thirty-eight couples were recruited from childbirth classes for a short-term longitudinal study. Mother's perceptions of activity, rhythmicity and mood were moderately stable from late pregnancy to 6 mth postnatally. Only father's perceptions of activity were stable during this time. Infants rated by parents as difficult on the Carey Infant Temperament Questionnaire at 6 mth were rated by observers as less responsive while being fed by their mothers. Results are discussed in the context of influences on parental perceptions of temperament.
Pre-seizure state identified by diffuse optical tomography

In epilepsy it has been challenging to detect early changes in brain activity that occurs prior to seizure onset and to map their origin and evolution for possible intervention. Here we demonstrate using a rat model of generalized epilepsy that diffuse optical tomography (DOT) provides a unique functional neuroimaging modality for noninvasively and continuously tracking such brain activities with high spatiotemporal resolution. We detected early hemodynamic responses with heterogeneous patterns, along with intracranial electroencephalogram gamma power changes, several minutes preceding the electroencephalographic seizure onset, supporting the presence of a “pre-seizure” state. We also observed the decoupling between local hemodynamic and neural activities. We found widespread hemodynamic changes evolving from local regions of the bilateral cortex and thalamus to the entire brain, indicating that the onset of generalized seizures may originate locally rather than diffusely. Together, these findings suggest DOT represents a powerful tool for mapping early seizure onset and propagation pathways.
The effects of projectile shape on laminated composite perforation

The development of damage in B/Al composite laminates subjected to high-velocity impact has been investigated by using the smoothed particle hydrodynamics (SPH) method. In lieu of a macrohomogenous, anisotropic medium, the composites are treated as a heterogeneous material. This model of the individual fibers and matrix separately is of importance, especially for predicting detailed damage mechanisms resulting from localized, intensive loadings. The numerical results show that damage in B/Al composite laminates due to high-velocity impact is caused not only by perforation but also by a great deal of delamination. It is also shown that for impact velocities exceeding the ballistic limit, a flat projectile can result in a larger perforation hole and more severe damage to the composite targets than a thick projectile with the same mass.
A Multiepitope of XBP1, CD138 and CS1 Peptides Induces Myeloma-Specific Cytotoxic T lymphocytes in T cells of Smoldering Myeloma Patients

We evaluated a cocktail of HLA-A2-specific peptides including heteroclitic XBP1 US184-192 (YISPWILAV), heteroclitic XBP1 SP367-375 (YLFPQLISV), native CD138260-268 (GLVGLIFAV) and native CS1239-247 (SLFVLGLFL), for their ability to elicit multipeptide-specific cytotoxic T lymphocytes (MP-CTLs) using T cells from smoldering multiple myeloma (SMM) patients. Our results demonstrate that MP-CTLs generated from SMM patients' T cells show effective anti-MM responses including CD137 (4-1BB) upregulation, CTL proliferation, interferon-γ production and degranulation (CD107a) in an HLA-A2-restricted and peptide-specific manner. Phenotypically, we observed increased total CD3(+)CD8(+) T cells (>80%) and cellular activation (CD69(+)) within the memory SMM MP-CTL (CD45RO(+)/CD3(+)CD8(+)) subset after repeated multipeptide stimulation. Importantly, SMM patients could be categorized into distinct groups by their level of MP-CTL expansion and antitumor activity. In high responders, the effector memory (CCR7(-)CD45RO(+)/CD3(+)CD8(+)) T-cell subset was enriched, whereas the remaining responders' CTL contained a higher frequency of the terminal effector (CCR7(-)CD45RO(-)/CD3(+)CD8(+)) subset. These results suggest that this multipeptide cocktail has the potential to induce effective and durable memory MP-CTL in SMM patients. Therefore, our findings provide the rationale for clinical evaluation of a therapeutic vaccine to prevent or delay progression of SMM to active disease.
PROGRAM EVALUATORS AND ETHICAL CHALLENGES A National Survey

A random sample of American Evaluation Association members was surveyed concerning the ethical challenges they encountered in their evaluation work Respondents who indicated that they had faced such challenges differed significantly (in amount and type of evaluation experience, as well as professional discipline) from those who said that they had never encountered an ethical conflict. Ethical problems associated with the reporting of findings by the evaluator were, by far, the most frequently mentioned. Also frequently described were conflicts involving the misinterpretation/misuse of results by stakeholders, contracting with stakeholders, and adherence to disclosure agreements. Aframeworkfor interpreting the study’s findings, based on understanding the subjective commitment of evaluators to the roles of scientist and/or helping