cssi/SciSciGPT-SciSciNet huggingface dataset:
[11C]PIB imaging in primary progressive aphasia and Alzheimer disease

192 Objectives: Progressive non-fluent aphasia (PNFA) is a neurodegenerative disorder characterized by gradually deteriorating expressive language function and variable progression to a more generalized dementia. There is currently no antemortem method to distinguish cases of PNFA related to Alzheimer’s from those caused by other disorders. In an effort to make this distinction, we examined whether PET imaging using the Pittsburgh Compound B, [11C]PIB revealed distinctive patterns of amyloid deposition in clinically diagnosed PNFA versus AD. Methods: Three patients with a clinical diagnosis of PNFA and three age- and gender-matched patients with mild probable AD were included in this study. All subjects underwent FDG-PET, PIB-PET and CT scans under an IRB-approved protocol. With both tracers, venous samples were used to generate blood time activity curves. Quantitative cerebral glucose utilization images were derived from the FDG scans and blood data. Modified Logan plots were generated with cerebellar references for the analysis of the PIB scans. Results: All subjects showed decreased cerebral metabolism, but in two PNFA patients hypometabolism was asymmetric with accentuated left-sided abnormalities in language-related cortical regions. All PNFA patients demonstrated bilateral cortical PIB retention, but the two patients with asymmetric FDG hypometabolism retained PIB to lesser degree. The one PNFA patient who progressed to a more generalized dementia showed FDG and PIB activity patterns similar to that of AD. Conclusions: The asymmetric distribution of PIB and lateralized cerebral hypometabolism observed in patients with PNFA may be useful in identifying this entity. The finding of PIB retention in all three PNFA subjects was unexpected given the lack of plaque pathology in as many as 2/3 of PNFA patients who have come to autopsy. This could reflect underlying AD pathology in these three cases, or binding of PIB to fibrillar proteins other than beta amyloid. Further studies of PIB binding in other PNFA cases are therefore warranted.
Wilson, Edward Osborne

Edward Osborne Wilson (1929–) is an American biologist, the world's leading authority on ants, who has explored biogeography. Keywords: biogeography; social behavior; consilience of inductions
Influence of purines and pyrimidines on cold hardiness of plants. V. Uptake and translocation of purines and pyrimidines in alfalfa.

Abstract Differential uptake of radioactive purines and pyrimidines by alfalfa leaves was observed. Translocation of radioactive constituents from leaves to stem-crown or root tissues (metabolic sinks) was not proportional to uptake. After 40 days of hardening at low temperatures, ranking of radioactivity levels changed for the base treatments and the change in leaves was different from that in whole plants. Ratios calculated for radioactivity from guanine and cytosine/adenine and uracil for RNA of leaves was twice as large as that for stem-crown or root tissues. More than 3 4 of the total radioactivity was found in soluble cytoplasm, although less than 10% of the RNA of hardened plants has been found in this fraction. This has special significance because soluble cytoplasm is the fraction that contains most of the polynucleotide phosphorylase activity and contains 60% of the soluble proteins that have been closely associated with cold tolerance.
The co-sintering of electrode and electrolyte layered structures for sofc applications

Planar designs for solid oxide fuel cells contain layered structures of electrode and electrolyte materials that must be co-sintered to produce flat, crack-free layers. In this work, the sintering behavior of model electrolyte (YSZ) and anode (NiO-based) materials was studied using in situ video observation of sintering individual materials and bi-layers at temperatures up 1350°C. The behavior of bi-layers was then compared to the predictions of a constrained sintering model.
Retinal Stem Cells

The vertebrate retina is a well-characterized central nervous system (CNS) structure, consisting of seven major cell types, which in adult are arranged in a stereotypical laminar organization. These cell types are born in an evolutionarily conserved temporal sequence: the majority of retinal ganglion cells (RGCs), horizontal cells, amacrine cells, and cone photoreceptors are born during early histogenesis, whereas the majority of rod photoreceptors, bipolar cells, and the Muller glia are generated during late histogenesis (1). Thus, as elsewhere in the CNS (2), neurogenesis in the retina precedes gliogenesis. Underlying cellular diversity in the retina is population of neural progenitors that generate stage-specific neurons and glia (3). Evidence from a variety of experimental approaches including cell ablation studies and in vivo lineage analyses demonstrated that neural progenitors in the developing retina were multipotential, possessing capacity to generate all seven retinal cell types, including the Muller glia (4, 5, 6, 7, 8). Although retinal progenitors have not been demonstrated to possess the potential of self-renewal (9,10), a hallmark of stem cells, they are included within the broad description of stem cells, with the assumption that they possess the potential of self-renewal. Potentially this is not demonstrable in vitro because of a lack of a conducive environment (3). In mammals and other warm-blooded vertebrates, neural stem cells are found only in the embryonic retina (11, 12, 13). Recently a quiescent population of neural stem cells with retinal potential has been identified in the ciliary epithelium of warm-blooded vertebrates (13, 14, 15). These cells are regarded as analogous to those found in the ciliary marginal zone (CMZ) of adult fish and frog retina (11,16,17). In adult fish, neural stem cells are not confined to CMZ but are also located in the inner retina and are regardedto generate rod photoreceptors during regeneration and in response to injury (16).
Design and analysis of an algorithm for fair service in error-prone wireless channels

In order to support diverse communication‐intensive real‐time and non‐real‐time data flows over a scarce, varying and shared wireless channel with location‐dependent and bursty errors, we define a service model that has the following characteristics: short‐term fairness among flows which perceive a clean channel, long‐term fairness for flows with bounded channel error, worst‐case delay bounds for packets, short‐term throughput bounds for flows with clean channels and long‐term throughput bounds for all flows with bounded channel error, expanded schedulable region, and support for both delay sensitive and error sensitive data flows. We present the wireless fair service algorithm, and show through both analysis and simulation that it achieves the requirements of the service model in typical wireless network environments. The key aspects of the algorithm are the following: (a) an enhanced fair queueing based service scheme that supports decoupling of delay and bandwidth, (b) graceful service compensation for lagging flows and graceful service degradation for leading flows, (c) support for real‐time delay sensitive flows as well as non‐real‐time error sensitive flows, and (d) an implementation within the framework of the simple and robust CSMA/CA wireless medium access protocol.
Exposed white dwarfs in dwarf novae

Hubble Space Telescope far ultraviolet spectroscopic observations of cataclysmic variable white dwarfs, exposed during dwarf nova quiescence, have yielded a number of new insights on accretional heating, photospheric abundances of the accreted atmosphere and rotational velocities of the underlying degenerates. Recent results of synthetic spectral analyses of HST spectra (and, in some cases, IUE spectra) are highlighted together with comparisons between time-dependent theoretical simulations of the heating effect of the dwarf nova accretion event on the underlying degenerate and actual spectroscopic observations of white dwarf surface cooling.
Potassium Chloride (KCI)

Publisher Summary The chapter describes various aspects of the optical constants—namely, refractive index n and extinction coefficient k for potassium chloride (KCl). The spectral region 3000-300 μm primarily contains absorption because of two and three-phonon absorption processes. Here, k is determined by the transmission measurements of slabs. Measurement is done with a grating monochromator utilizing an Hg lamp and the harmonics of a 12-ram Klystron as sources. The tabulated numbers were read from a wavelength graph with a smooth line drawn through the data points, which scattered. It is noted that the more-limited results of Stolen and Dransfeld at 300 K are in good agreement, with the temperature dependence studied in detail. The spectral region 200-30 μm is studied by Johnson and Bell by asymmetric Fourier-transform spectroscopy. This technique yields the phase and amplitude of the reflectivity experimentally, thus circumventing Kramers-Kronig (KK) analysis of R or oscillator-model fits. At the reststrahlen minimum, a power reflectance of 0.0004 is measured, which suggests little polishing damage.
Late Effects of Breast Radiotherapy in Young Women

Radiotherapy (RT) to the breast or chest wall of young women is associated with long-term cardiotoxicity and an increased risk of secondary breast cancers. As many patients with early stage breast cancer and Hodgkin's disease are cured of their disease, there is significant concern regarding the long term risks of therapy. Older RT techniques for treating the breast/chest wall and draining lymph nodes for breast cancer resulted in a relatively high dose being delivered to a substantial volume of heart, and convincing evidence exists of excess cardiovascular morbidity and mortality in patients treated with these techniques. While modem RT techniques have reduced radiation exposure to the heart, they have not eliminated it. Many large studies of Hodgkin's disease survivors have demonstrated a clear risk of secondary breast cancer development after mantle RT for Hodgkin's disease. The risk of developing breast cancer after mantle RT appears to be related to age at time of irradiation, dose delivered to the breast tissue, and whether or not chemotherapy is incorporated into the overall treatment plan. In this article we review late cardiac complications associated with tangential breast RT and the risk of developing a secondary breast cancer after mantle RT for Hodgkin's disease.
The Practice of Prelates: Tyndale's Papal Narrative and its German Model

AbstractAmong the most interesting sections of William Tyndale's Practice of Prelates (1530) is his account of the medieval papacy's rise to ecclesiastical primacy and temporal power. This account, in its structure, contents and some of its imagery, closely follows a section of an anonymous Reformation tract, Vom alten und nuen Gott, Glauben und Ler (Basel, 1521). The two publications include parallel histories of the popes' dealings with the Carolingian dynasty. However, the papal narrative has a somewhat different purpose and orientation in Tyndale's work than it does in his source. In Vom alten und nuen Gott, the story of papal aggrandizement is part of an exposition of medieval distortions of Christianity, which the text contrasts with the recovered Gospel of the reformers. Seeing the difference should help 'all Chrysten men' find their way through the religious upheavals of the early sixteenth century. Whereas Vom alten und nuen Gott thus brings the papal narrative into relation to a dilemma of all C...
Bridging the Gap between Desktop and the Cloud for eScience Applications

The widely discussed scientific data deluge creates a need to computationally scale out eScience applications beyond the local desktop and cope with variable loads over time. Cloud computing offers a scalable, economic, on-demand model well matched to these needs. Yet cloud computing creates gaps that must be crossed to move existing science applications to the cloud. In this article, we propose a Generic Worker framework to deploy and invoke science applications in the cloud with minimal user effort and predictable cost-effective performance. Our framework addresses three distinct challenges posed by the cloud: the complexity of application deployment, invocation of cloud applications from desktop clients, and efficient transparent data transfers across desktop and the cloud. We present an implementation of the Generic Worker for the Microsoft Azure Cloud and evaluate its use for a genomics application. Our evaluation shows that the user complexity to port and scale the application is substantially reduced while introducing a negligible performance overhead of of <; 5% for the genomics application when scaling to 20 VM instances.
Republicans do it better

(2000). Republicans do it better. Bulletin of the Atomic Scientists: Vol. 56, No. 5, pp. 17-19.
High-resolution cytogenetic characterization of telomeric associations in ring chromosome 19

High-resolution cytogenetic studies of a normal individual with ring chromosome 19 indicate that, at the late-to-mid prophase level of band resolution, no apparent chromosomal material is missing, and that telomeric fusion/association, not deletion, is the cause of the ring chromosome formation. Sub-band analysis of the telomeric fusion shows thin chromatin filaments between the telomeres of some of the very elongated ring chromosomes, which cannot be resolved by metaphase chromosome analysis. The ring chromosome found in this individual shows evidence of the characteristic instability associated with ring chromosomes, including duplicated segments, double rings, and subsequent loss of the ring resulting in cells with monosomy 19. The lack of phenotypic effect and the unstable ring behavior, unlike previously reported patients with ring 19, support the formation of this ring by telomeric association.
Linearization Error in Electrical Impedance Tomography

Abstract—In borehole electromagnetic tomography and resistivity survey a linearized model approximation is often used, in the context of regularized regression, to image the conductivity distribution in a domain of interest. Due to the error introduced by the simplified model, quantitative image reconstruction becomes challenging without implementing a nonlinear algorithm. We derive a closed form expression of the linearization error in electrical impedance tomography based on the complete electrode model. The error term is expressed in an integral form involving the gradient of the perturbed electric potential in the interior of the domain and renders itself readily available for analytical or numerical computation. For real isotropic conductivity inhomogeneities with piecewise uniform characteristic functions the perturbed potential field can be shown to satisfy Poisson’s equation with Robin boundary conditions and interior point sources positioned at the interfaces of the inclusions. Simulation experiments using a finite element method have been performed to validate these results.
GRAIN BOUNDARY CHEMISTRY OF NiAl

Etude par sonde atomique-microscopie ionique a emission de champ de la composition chimique des joints de grains dans l'alliage Ni-49% at. Al. Il existe une majorite de regions qui ne contiennent pratiquement pas d'aluminium, et quelques regions qui indiquent aucun enrichissement ou depletion en aluminium. La zone depletee en aluminium semble etre la cause de l'augmentation de ductilite et de la variation du mecanisme de rupture intervenant dans l'alliage intermetallique par comparaison aux alliages NiAl plus eloignes de la stœchiometrie
Mechanomyographic and electromyographic time and frequency domain responses during submaximal to maximal isokinetic muscle actions of the biceps brachii

The purpose of this investigation was to determine the mechanomyographic (MMG) and electromyographic (EMG) amplitude and mean power frequency (MPF) versus torque relationships during isokinetic muscle actions of the biceps brachii. Twelve adults [mean (SD) age, 22.2 (2.7) years] performed submaximal to maximal isokinetic muscle actions of the dominant forearm flexors. Following determination of isokinetic peak torque (PT), the subjects randomly performed submaximal muscle actions in 20% increments from 20% to 80% PT. Polynomial regression analyses indicated linear increases in both MMG (r 2=0.984) and EMG (r 2=0.988) amplitude to 100% PT. There were no significant (P>0.05) relationships, however, for MMG and EMG MPF versus isokinetic torque. The results demonstrated similar responses for MMG and EMG in both the time and frequency domains. These findings suggested that simultaneous examination of MMG and EMG amplitude and MPF may be useful for describing the unique motor control strategies that modulate dynamic torque production. Furthermore, the results indicated that dynamic muscle actions can be used when applying techniques that require a linear EMG amplitude versus torque relationship.
EFFECT OF COLOR OF TRAY COVER ON DIETARY INTAKE OF ELDERLY LONG‐TERM CARE PATIENTS

The study was conducted to investigate whether the dietary intake of patients who are in marginal deficiency state because of lack of environmental stimulus could be affected by color of tray cover. Subjects were elderly women between the ages of 70 and 90 and were 5% below ideal body weight. All of the subjects were able to feed themselves. Four colors were selected for tray covers: red, yellow, black and white. The study was conducted over an 8-week period of 56 days. A percentage was assigned to each menu item on the tray. After the patients had finished the noon meal their percentage intake was recorded. Colors of tray covers were changed daily in a selective fashion. The data were analyzed using analysis of variance, repeated measures design. The mean total percentage of meals consumed by subjects for red was 82 ± 12%. The mean result for yellow was 82 ± 23%. The mean result for black was 82 ± 11%. The mean result for white was 82 ± 11%. The means were within 0.7% of each other. With an F ratio of 0.10 it was concluded that the colors red, yellow, black, and white did not have any affect on percentage of meal consumed by subjects tested.
The Effect of Strong Versus Weak Evidence on the Assessment of Race Stereotypic and Race Nonstereotypic Crimes1

The effects of defendant race, type of crime, and strength of evidence on the perception and evaluation of criminal offenses were examined. Consistent with past research, defendants accused of race stereotypic crimes were more likely to be perceived as guilty and as more typical offenders than were defendants accused of race nonstereotypic crimes. The strength of evidence supplied to subjects did moderate the interaction between defendant race and type of crime on some of the punishment items. These findings and their implications for future related research are discussed.
Three layers of working memory: Focus-switch costs and retrieval dynamics as revealed by the N-count task

Two experiments explored the process of switching items in and out of the focus of attention using a new paradigm, the N count task (adapted from Garavan, 1998; N varied from 1 to 4). This task yielded a focus size of one, indicated by a substantial focus switch cost for 2 count. Additionally, the focus switch costs in response time increased with working memory load, indicating an effortful search process occurring at a speed of about 240 ms/item. Maintaining and switching to and from a passive load did not increase the focus switch costs or decrease memory accuracy, indicating that there is no crosstalk between passive and active items. The results support a concentric theory of working memory: a small focus at its core, a surrounding area of (at least) three readily available items referred to as the outer store, and a still wider region of passive storage, possibly more long term memory than working memory.
Horizontally elongated optic nerve heads.

Lindsay A. Kuester et al. (Veterinary Ophthalmology, V. 7, no. 3, 169–173, 2004) note that ‘The squirrel is the only mammal, to our knowledge, with a dramatically horizontally elongated ONH.’ We wish to expand upon that knowledge by noting that we have observed a similarly shaped optic nerve head (ONH) in various members of the deer family including the white-tailed deer ( Odocoileus virginianus ; Fig. 1a); 1 the fallow deer ( Cervus dama ; Fig. 1b); 1 red brocket deer ( Mazama americana ; Fig. 1c); 2 Pere David’s deer ( Elaphurus davidianus ; Fig. 1d); 2 and red deer ( Cervus elaphus ). 3 We concur with Kuester et al . that the ‘why’ relating to this shape is not readily discernible; especially in that deer would most likely have a rod-dominant retina vs. the conedominant squirrel.
Receptor binding sites for substance P, but not substance K or neuromedin K, are expressed in high concentrations by arterioles, venules, and lymph nodules in surgical specimens obtained from patients with ulcerative colitis and Crohn disease.

Abstract Several lines of evidence indicate that tachykinin neuropeptides [substance P (SP), substance K (SK), and neuromedin K (NK)] play a role in regulating the inflammatory and immune responses. To test this hypothesis in a human inflammatory disease, quantitative receptor autoradiography was used to examine possible abnormalities in tachykinin binding sites in surgical specimens from patients with inflammatory bowel disease. Surgical specimens of colon were obtained from patients with ulcerative colitis (n = 4) and Crohn disease (n = 4). Normal tissue was obtained from uninvolved areas of extensive resections for carcinoma (n = 6). In all cases, specimens were obtained less than 5 min after removal to minimize influences associated with degradation artifacts and were processed for quantitative receptor autoradiography by using 125I-labeled Bolton-Hunter conjugates of NK, SK, and SP. In the normal colon a low concentration of SP receptor binding sites is expressed by submucosal arterioles and venules and a moderate concentration is expressed by the external circular muscle, whereas SK receptor binding sites are expressed in low concentrations by the external circular and longitudinal muscle. In contrast, specific NK binding sites were not observed in any area of the human colon. In colon tissue obtained from ulcerative colitis and Crohn disease patients, however, very high concentrations of SP receptor binding sites are expressed by arterioles and venules located in the submucosa, muscularis mucosa, external circular muscle, external longitudinal muscle, and serosa. In addition, very high concentrations of SP receptor binding sites are expressed within the germinal center of lymph nodules, whereas the concentrations of SP and SK binding sites expressed by the external muscle layers are not altered significantly. These results demonstrate that receptor binding sites for SP, but not SK or NK, are ectopically expressed in high concentrations (1000-2000 times normal) by cells involved in mediating inflammatory and immune responses. These data suggest that SP may be involved in the pathophysiology of inflammatory bowel disease and might provide some insight into the interaction between the nervous system and the regulation of inflammation and the immune response in human inflammatory disease.
Higher-order Darboux transformations with foreign auxiliary equations and equivalence with generalized Darboux transformations

Abstract We show that a recently developed modified Darboux transformation that uses foreign auxiliary equations, can be unified with the Darboux transformation for generalized Schrodinger equations. As a consequence of this unification, we obtain explicit Darboux transformations with foreign auxiliary equations of arbitrary order.
TU‐C‐BRA‐04: A New Approach to Model‐Based Dose Calculations for Kilovoltage Beams

Purpose: The additional radiationdose delivered to radiotherapy patients from repeated image guidance procedures is a growing concern. This study presents a new approach to model‐based dose calculation that overcomes the deficiencies of currently available model‐based algorithms in the kilovoltage regime. Method and Materials:Monte Carlo techniques were used to calculate the dose to patients resulting from kV‐CBCT scans for multiple scan sites including the head‐and‐neck, chest, and pelvis. Both dose‐to‐medium and dose‐to‐water were calculated using realistic simulated kV‐CBCT beams to find a correlation between the effective thickness of bone (dEB) traversed by an x‐ray beam to reach a voxel and the correction factor needed to correct the model‐based dose calculation. A program was written to facilitate the calculation of dEB in which the incident beam profiles and isocenter relative to a scanned patient were taken into account. Results: A strong correlation between dose correction factor and dEB was observed. A unique correction factor calibration curve as a function of dEB was derived and used to predict patient dose. Compared to gold standard Monte Carlo calculated dose distributions, the resulting mean dose error for each patient was less than 3% for bone and 2% for soft‐tissue. This was in contrast to model‐based calculations, which resulted in mean errors of up to −103% for bone and 8% for soft‐tissue. Conclusion: The derived correction factor as a function of effective bone thickness is capable of accurately calculating the dose to bone and soft‐tissue by making use of patient CT data and the incident kV‐CBCT beam information. The accuracy of this new approach is patient and scan site independent because it takes into account the spectral changes of the x‐ray beam. With the addition of a commissioned kV‐CBCT beam this new approach can facilitate inclusion of imagingdose in radiotherapytreatment planning.
Can Tinto's Student Departure Model Be Applied To Nontraditional Students?:

While Tinto's student departure model has been tested and supported in numerous studies, it has not yet been applied to nontraditional students. This study attempted to find out whether Tinto's model, in particular the concepts of academic and social integration, can explain retention among nontraditional students. Attrition rates of 25 adult learner classes in a college of management and business were calculated. Four independent variables were entered into a regression equation in an attempt to explain attrition from these classes. They were: social, academic, and career integration; and the size of each class. The data showed that classes that were socially integrated and smaller were better able to retain their students than the less socially integrated and larger-sized classes. The data suggest that what keeps adult learners in educational programs is the social environment in which the learning takes place.
MO-A-BRB-01: Non-Coplanar Rotational Therapy by Using High Efficient Unflattened Beams

The rapid dose fall‐off from treatment target to the adjacent critical organs has been the Holy Grail for radiotherapytreatment planning. The modern treatment delivery technologies to address such goal include volumetric modulated rotational therapy, non‐coplanar EVIRT beams and the use of unflattened beams to reduce the penumbra area. In this lecture, the integration of above techniques will be presented to achieve the goal of a sharp gradient dose around the target and also the discussion of middle to low dose volumes. Use of volumetric modulated rotational therapy by multiple non‐coplanar arcs is an idea treatment modality to focus the high dose in the target area while spreading the low dose to even larger volume to reduce the middle range dose to surrounding critical organs. This is especially important for SBRT treatment plans since the fraction dose is much higher than the traditional fraction schema. The challenges we face today are 1. the gantry‐couch (patient) collision issue for non‐coplanar beam angles, 2. the treatment delivery efficiency due to multiple arc rotations and 3. the massive inverse optimization computation for multiple rotational arcs can be resource intensive and time consuming for treatment plan systems. It might not be easy to resolve all the challenges at one time. However, the high efficient unflattened beam can certainly improve the delivery speed by reducing the beam‐ on time and this, again, is essential to SBRT patients with high fractional dose. In this lecture, the non‐coplanar rotational therapy treatment planning techniques will be presented and be evaluated by using comformality index, gradient index as well as dose volume histogram comparison. The differences in treatment delivery time will be tabulated and compared. At the end, the high‐medium‐low dose volumes will be illustrated with radiobiological models for the philosophy of sun tanned versus sun burned. Learning Objectives: 1. Understand treatment plan and dose gradient advantages of using non‐ coplanar rotational therapy 2. Understand potential delivery efficiency by using unflattened beams for multiple non‐coplanar rotational beams 3. Understand sun tanned versus sun burned: the low dose volume and integrated dose
Some fundamental ideas in topology and their application to problems in metallurgy

Abstract The topological ideas and results that have been used by metallurgists, together with several results not previously presented in the metallurgical literature, are developed in a systematic manner. Based on this presentation, a review is given of the use of topology in metallurgy. The additional topology that is introduced includes the Alexander duality theorem, the Euler-Poincare formula, and the concept of deformation retract. These concepts are used to establish interrelationships among the results of several papers and to clarify the mathematical treatment.
Ventral hippocampal α4β2 nicotinic receptors and chronic nicotine effects on memory

Abstract Chronic nicotine administration has been repeatedly shown to facilitate working memory function in rats on the radial-arm maze. The critical neural mechanisms for this effect are still being discovered. The nicotinic nature of the chronic nicotine induced memory improvement is supported by the finding that it is blocked by chronic mecamylamine co-infusion. The hippocampus also appears to be critically important. Hippocampal ibotenic acid lesions block the effect. Within the hippocampus, we have found that the α4β2 nicotinic receptor subtype is involved in memory functioning. Acute ventral hippocampal infusions of the α4β2 nicotinic antagonist dihydro-β-erythroidine (DHβE) significantly decreased working memory performance in the radial-arm maze. The aim of the current study was to determine the importance of α4β2 receptors within the ventral hippocampus for the memory enhancing effects of chronic nicotine treatment. Adult female Sprague–Dawley rats were trained on the 8-arm radial maze and were cannulated bilaterally in the ventral hippocampus. Osmotic minipumps administering chronic nicotine at a rate of 5 mg per kg per day were also implanted in the nicotine treatment rats. Control rats received saline-only minipumps. For a period of 4 weeks after surgery, each rat received bilateral hippocampal infusions of 0, 2, 6 and 18 μg per side of DHβE and tested for memory performance on the radial-arm maze. Radial-arm maze choice accuracy was impaired by acute hippocampal DHβE infusion in a dose-related fashion. This acute hippocampal DHβE-induced choice accuracy impairment was eliminated by chronic systemic nicotine infusion. Chronic nicotine in combination with acute vehicle hippocampal infusion was not seen to alter choice accuracy. Response latency was not found to be altered by acute hippocampal DHβE in the absence of chronic nicotine administration, but it did attenuate the response latency reduction induced by chronic nicotine infusion. Wet dog shakes were not found to be affected by hippocampal DHβE when given without chronic nicotine. Wet dog shakes were significantly increased by chronic nicotine infusion. Intra-hippocampal DHβE significantly potentiated this effect. The results from the current study reinforce the hypothesis that ventral hippocampal α4β2 nicotinic receptors are important for memory function. These receptors may also have a role to play in the development of other aspects of behavior associated with chronic nicotine treatment.
Quintessence, cosmic coincidence, and the cosmological constant

Recent observations suggest that a large fraction of the energy density of the Universe has negative pressure. One explanation is vacuum energy density; another is quintessence in the form of a scalar field slowly evolving down a potential. In either case, a key problem is to explain why the energy density nearly coincides with the matter density today. The densities decrease at different rates as the Universe expands, so coincidence today appears to require that their ratio be set to a specific, infinitesimal value in the early Universe. In this paper, we introduce the notion of a ``tracker field,'' a form of quintessence, and show how it may explain the coincidence, adding new motivation for the quintessence scenario.
Squeezing the most out of interference: An optimization framework for joint interference exploitation and avoidance

There is a growing interest in exploiting interference (rather than avoiding it) to increase network throughput. In particular, the so-called successive interference cancellation (SIC) scheme appears very promising, due to its ability to enable concurrent receptions from multiple transmitters as well as interference rejection. Although SIC has been extensively studied as a physical layer technology, its research and advances in the context of multi-hop wireless network remain limited. In this paper, we try to answer the following fundamental questions. What are the limitations of SIC? How to overcome such limitations? How to optimize the interaction between SIC and interference avoidance? How to incorporate multiple layers (physical, link, and network) in an optimization framework? We find that SIC alone is not adequate to handle interference in a multi-hop wireless network, and advocate the use of joint SIC and interference avoidance. To optimize a joint scheme, we propose a cross-layer optimization framework that incorporates variables at physical, link, and network layers. This is the first work that combines successive interference cancellation and interference avoidance in multi-hop wireless network. We use numerical results to affirm the validity of our optimization framework and give insights on how SIC and interference avoidance can complement each other in an optimal manner.
Further developments in estimation of the largest mean of K normal populations

We revisit the bounded maximal risk point estimation problem as well as the fixed-width confidence interval estimation problem for the largest mean amongk(≥2) independent normal populations having unknown means and unknown but equal variance. In the point estimation setup, we devise appropriate two-stage and modified two-stage methodologies so that the associatedmaximal risk can bebounded from aboveexactly by a preassigned positive number. Kuo and Mukhopadhyay (1990), however, emphasized only the asymptotics in this context. We have also introduced, in both point and interval estimation problems,accelerated sequential methodologies thereby saving sampling operations tremendously over the purely sequential schemes considered in Kuo and Mukhopadhyay (1990), but enjoying at the same time asymptotic second-order characteristics, fairly similar to those of the purely sequential ones.
Supervisory Bullying, Status Inequalities and Organizational Context

Bullying has been increasingly identified as a significant social problem. Although much of this attention has centered on the context of schooling, researchers are now beginning to recognize that workplaces are also arenas rife with abusive, bullying behaviors. Personality attributes of bullies and victims have received attention, but much less research has examined the social and organizational foundations of bullying. In this article, we focus theoretical attention on the importance of status-based power differentials and organizational context for the emergence of supervisory bullying in employment. Our multi-method analyses, which draw from content-coded organizational ethnographies (N = 204), highlight the importance not only of structural and social vulnerability – such as being in a racial minority or of a low occupational position – but also of chaotic and disorganized workplaces. Poor workplace organization, we show, creates positive motivations for supervisory bullying. Workplaces without capable guardians create further vulnerabilities to bullying as a managerial control tactic. We conclude by discussing the theoretical implications of our results for understanding social power, organizational dynamics and the ramifications of abuse in the workplace.
Some effects of fly ash (from coal burning) on bush bean plants grown in solution culture

Abstract Bush bean plants (Phaseolus vulgaris L. C. V. Improved Tendergreen) were grown for 14 days in 3700‐ml solution cultures with varying application rates of fly ash from a coal burning plant in California. Plants were also grown in a solution culture experiment in the presence of tiie chelating agent DTPA (diethylene triamine pentaacetic acid) and also in solutions acidified with HCl. The latter treatments were to determine if metals in the fly ash could be made more available to plants. The higher levels of fly ash (5 to 10 g/3700 ml) resulted in increased Ca, B, Si, Sr, and Ba in leaves, stems, and roots. No plants, however, appeared to have an excess of trace metals. In another experiment DTPA and HCl amendments failed to increase greatly the availability of trace metals from the fly ash in solution culture except for Zn. In this experiment the fly ash was the sole source of Ca and plants were deficient in Ca because insufficient fly ash was added. The fly ash resulted in increased Zn, Ca, Fe, Mn...
Effective ply and constituent elastic properties for cracked laminates

Abstract Symmetric laminates with cracked plies were studied utilizing finite element unit cell models. The laminate unit cell models were developed based on periodicity which assumes uniformly spaced cracks. A volume-averaging scheme was developed for evaluating the volume-averaged stresses, strains and effective residual properties in the cracked plies. Sensitivities of residual properties to several material parameters were examined. The predictions of the finite element model were found to be in good agreement with published experimental results. Finally, an approach is described for computing the effective fiber and matrix properties, from the effective lamina properties, as required for progressive failure analysis using multicontinuum theory. It was found that, even though the fibers are undamaged, their effective continuum properties in the transverse direction must be degraded to achieve constituent properties that coincide with the damage mode and the residual effective ply properties.
Organization size as an influence on perceived organizational goals: A comparative study among American, Japanese, and Korean managers

Abstract This study examined the influence of organizational size on perceived organizational goals in management jobs. Data from over 1400 American, Japanese, and Korean managers are presented. A comparative analysis of the three country data shows that there is a general trend of increasing behavioral relevance scores of organizational goals from small to large companies.
A Look at Lattice Artifacts in Weak Matrix Elements

Abstract Realistic estimates for systematic errors in weak matrix elements from the lattice are crucial for phenomenological applications. An important source of uncertainty is momentum dependent discretization errors. Pseudoscalar meson leptonic decays provide a good laboratory to explore momentum dependent cutoff effects.
Abrupt onsets cannot be ignored

Participants identified target letters at cued locations in the presence of occasional abrupt onsets of new distractor letters. The onsets distracted the participants and impaired their letter identification performance despite confirmation that they were using the information provided by the cue. This result contrasts with earlier results found by other researchers that revealed an ability of participants to ignore abrupt onsets in some cases. Our results, however, were obtained under conditions that prevented anticipatory eye movements to the target. In a subsequent experiment when participants were permitted to look at the target in advance, the distracting effect of the onsets was eliminated, suggesting that participants may have looked at the target in the earlier studies. We conclude that abrupt onsets cannot be ignored unless the target element receives a substantial advantage via fixation.
Sample preparation for the analysis of flavors and off-flavors in foods

Off-flavors in foods may originate from environmental pollutants, the growth of microorganisms, oxidation of lipids, or endogenous enzymatic decomposition in the foods. The chromatographic analysis of flavors and off-flavors in foods usually requires that the samples first be processed to remove as many interfering compounds as possible. For analysis of foods by gas chromatography (GC), sample preparation may include mincing, homogenation, centrifugation, distillation, simple solvent extraction, supercritical fluid extraction, pressurized-fluid extraction, microwave-assisted extraction, Soxhlet extraction, or methylation. For high-performance liquid chromatography of amines in fish, cheese, sausage and olive oil or aldehydes in fruit juice, sample preparation may include solvent extraction and derivatization. Headspace GC analysis of orange juice, fish, dehydrated potatoes, and milk requires almost no sample preparation. Purge-and-trap GC analysis of dairy products, seafoods, and garlic may require heating, microwave-mediated distillation, purging the sample with inert gases and trapping the analytes with Tenax or C18, thermal desorption, cryofocusing, or elution with ethyl acetate. Solid-phase microextraction GC analysis of spices, milk and fish can involve microwave-mediated distillation, and usually requires adsorption on poly(dimethyl)siloxane or electrodeposition on fibers followed by thermal desorption. For short-path thermal desorption GC analysis of spices, herbs, coffee, peanuts, candy, mushrooms, beverages, olive oil, honey, and milk, samples are placed in a glass-lined stainless steel thermal desorption tube, which is purged with helium and then heated gradually to desorb the volatiles for analysis. Few of the methods that are available for analysis of food flavors and off-flavors can be described simultaneously as cheap, easy and good.
Circumcision on the web: a comparison of quality, content, and bias online.

Abstract Objective In 2012, the American Academy of Pediatrics (AAP) newborn circumcision policy statement expressed that although benefits outweigh risks, final decisions lie with parents. Although health information on the Internet is plentiful, the quality and availability of information on circumcision, including dissemination of AAP and AUA policy statements, is unknown. We analyzed English and Spanish circumcision websites to evaluate their overall quality, detail, accuracy, and bias. Methods In April 2013, three search engines were queried for English and Spanish circumcision websites, which were analyzed utilizing the DISCERN Plus scale for content quality as well as additional study-specific criteria. Results We analyzed 214 websites (141 English, 73 Spanish). Most websites in both languages had very good content quality and were neutral regarding circumcision. Regardless of language, only 21% of sites mentioned the updated AAP guidelines. Surprisingly, the AUA circumcision policy statement did not appear in the top results. Spanish sites were more likely to give good descriptions of circumcision procedures than English sites (p Conclusions Newborn circumcision information on the Internet is of very good quality, but different English and Spanish characteristics possibly reflect cultural bias, which may explain the disparate rates of circumcision between different groups in the USA. The AAP's circumcision policy statement was referenced by a minority (20%) of websites, and AUA's policy statement was not even part of the top results. The AUA should have a more active role in providing accurate and comprehensive online information to parents regarding circumcision.
Zinc silicophosphate cement: influence of composition on the acid solubility and fluoride content of enamel.

Abstract A series of experiments were conducted to determine the effect of the silicate concentration in zinc silicophosphate cements on the fluoride uptake and acid solubility of intact enamel. The cement prepared from powders that contained 50 and 90 per cent silicate powder produced an increase in fluoride and a reduction in the calcium solubility. The magnitude of change was approximately twice as great with the 90 per cent silicate as with the 50 per cent silicate formulation. Use of the cement prepared from the powder which contained only 10 per cent silicate had no appreciable effect.
Maintaining Your Focus in Focus Groups: Avoiding Common Mistakes

Focus groups are used frequently in nursing research as a method for collecting qualitative data. However, due to inadequate planning or execution, the results can be of poor quality or even worthless. A well-defined purpose, carefully planned environment, and well trained personnel are discussed as the cornerstones to focus group success. This article sets the stage with a description of a well conducted focus group, then provides examples and a critique of less-than-effective groups. Focus groups can be powerful and effective when their use is appropriate to the study purpose, the environment is non-judgmental and welcoming, and the personnel are skilled.
Graduated driver license nighttime compliance in U.S. teen drivers involved in fatal motor vehicle crashes.

BACKGROUND: Examination of teen driver compliance with graduated driver licensing (GDL) laws could be instrumental in identifying factors associated with persistently high motor vehicle mortality rates. METHODS: Fatality analysis reporting system (FARS) data from the years 2006 to 2009 were used in this nation-wide cross-sectional study of drivers covered by a state nighttime GDL law (n=3492). A new definition of weekend, based on the school night in relation to the teenage social landscape, redefined Friday night as a weekend night and Sunday night as a weekday/school night and compared it to previous weekend definitions. Multiple logistic regression was used to examine independent effects of demographic, behavioral, environmental, contextual, and other factors on compliance with nighttime GDL laws. All analyses were performed in Stata version 11. RESULTS: Given coverage under nighttime GDL laws, drivers aged 15-17 years were non-compliant in 14.9% of the fatal MVCs in which they were involved, and nearly one-fifth (18.8%) of all fatalities aged 15-17 years were associated with non-compliance. Mortality risk was 10% higher using a revised social (school night) versus traditional (Sat-Sun) weekend definitions. In multivariable analysis, drivers non-compliant with nighttime GDL laws were more likely to be drinking (OR=4.97, 3.85-6.40), unbelted (OR=1.58, 1.25-1.99), driving on the weekend (OR=1.82, 1.47-2.24), and killed (OR=1.31, 1.04-1.65). CONCLUSION: GDL non-compliance contributes to teen motor vehicle mortality. Legislative and enforcement efforts targeting non-school night driving, seatbelt nonuse and alcohol have potential to further reduce teen driving mortality. Language: en
Pattern perception - Integrating information presented in two modalities.

Subjects were required to organize and identify temporal patterns composed of either (i) two stimuli in one modality; (ii) two stimuli in each of two modalities, with the pattern alternately presented in the two modalities; or (iii) one stimulus in each of two modalities. Patterns (i) and (iii) are organized as structured patterns, but (ii) is organized by modality, not by pattern structure. When elements of a pattern appear in two modalities, the auditory-tactual combination produces the poorest performance.