cssi/SciSciGPT-SciSciNet huggingface dataset:
Molecular Mechanism of Natural Killer Cell-Mediated Cytotoxicity

Cytotoxic effector systems mediated by cells and humoral factors have been discovered and appear to play an important role in the host defense mechanism against infection and newly arising neoplasia. Several cytotoxic effector cells have been characterized, all of which have in common the ability to interact with and destroy unwanted target cells. However, the underlying molecular mechanism by which the cytotoxic cell destroys the target is not yet completely resolved. Several potential mechanisms have been proposed for cell mediated cytotoxicity (CMC), such as the necessity of cell to cell contact resulting in membrane perturbation, transfer of cytotoxic materials from the effector to the target, co-factors present on target cells that facilitate lysis, pore formation, etc. It is possible that all of these mechanisms may participate in a particular cytolytic reaction and different mechanisms may operate with different cytotoxic effector cells.
Federated Learning over Noisy Channels: Convergence Analysis and Design Examples

Does Federated Learning (FL) work when both uplink and downlink communications have errors? How much communication noise can FL handle and what is its impact to the learning performance? This work is devoted to answering these practically important questions by explicitly incorporating both uplink and downlink noisy channels in the FL pipeline. We present several novel convergence analyses of FL over simultaneous uplink and downlink noisy communication channels, which encompass full and partial clients participation, direct model and model differential transmissions, and non-independent and identically distributed (IID) local datasets. These analyses characterize the sufficient conditions for FL over noisy channels to have the same convergence behavior as the ideal case of no communication error. More specifically, in order to maintain the O(1/T) convergence rate of FedAvg with perfect communications, the uplink and downlink signal-to-noise ratio (SNR) for direct model transmissions should be controlled such that they scale as O(t^2) where t is the index of communication rounds, but can stay constant for model differential transmissions. The key insight of these theoretical results is a "flying under the radar" principle - stochastic gradient descent (SGD) is an inherent noisy process and uplink/downlink communication noises can be tolerated as long as they do not dominate the time-varying SGD noise. We exemplify these theoretical findings with two widely adopted communication techniques - transmit power control and diversity combining - and further validating their performance advantages over the standard methods via extensive numerical experiments using several real-world FL tasks.
Dislocation drag and its influence on elastic precursor decay

Abstract Plastic deformation is mediated by the creation and movement of dislocations, and at high stress the latter is dominated by dislocation drag from phonon wind. By simulating a 1-D shock impact problem we analyze the importance of accurately modeling dislocation drag and dislocation density evolution in the high stress regime. Dislocation drag is modeled according to a first-principles derivation as a function of stress and dislocation character, and its temperature and density dependence are approximated to the extent currently known. Much less is known about dislocation density evolution, leading to far greater uncertainty in these model parameters. In studying anisotropic fcc metals with character dependent dislocations, the present work generalizes similar earlier studies by other authors.
Stress, Anxiety, Binge Drinking, and Substance Use Among College Student-Athletes: A Cross-Sectional Analysis

The immense pressure faced by college student-athletes to balance participation in sports with other responsibilities can contribute to unhealthy coping behaviors including alcohol and drug use. We administered online surveys to 188 college student-athletes to examine stress, athletics-related anxiety, and perceived control of stress as predictors of binge drinking, substance use, and associated risk behaviors. Participants rated athletics as the second greatest source of stress in their lives, trailing only academics. Athletics-related anxiety was a significant predictor of cannabis use and substance-related risk behaviors, and represents an understudied area in the literature. Reports of alcohol and drug use in our sample were comparable to national surveys of student-athletes, but opioid misuse was troublingly high. Participants over the age of 21 and males were more likely to report substance use and risk behaviors. Athletes are susceptible to orthopedic injury and associated pain, which may lead to early exposure to opioids with high potential for abuse. Interventions for this population must target social contributors to substance use among student-athletes, opioid prescription and misuse as a gateway to opioid use disorders, and untreated anxiety as a potential driver of substance use, including anxiety associated with athletic performance.
An Introduction to the Theory of Knowledge: Internalism, externalism, and epistemic circularity

In the last chapter, we examined a reliability theory of justification. In this chapter, we will continue to explore issues concerning justification, knowledge, and reliability. In the first section, we will focus on the debate between “internalism” and “externalism,” two very general views about the nature of epistemic justification. In the last two sections, we shall consider some issues concerning how we know that any of our ways of forming beliefs, such as perception and memory, are reliable. Suppose, for example, that the only way to support the reliability of memory involves using memory. Would that way of supporting the reliability of memory be epistemically unacceptable? Would it prevent us from knowing that it is reliable? We shall consider some different answers to such questions. We shall focus mainly on the views of William Alston and Ernest Sosa. Internalism and externalism In the previous chapters, we considered a variety of theories about epistemic justification, including different forms of foundationalism, coherentism, and reliabilism. In the past twenty years, many philosophers have classified these theories of epistemic justification as either internalist or externalist . Internalism and externalism are general views about what is relevant to epistemic justification. Assessing the debate between internalists and externalists is difficult because different writers often use the terms “internalism” and “externalism” to mean different things. Still, it is worth considering some of the main issues that arise in the debate. Let's consider one common way of drawing the distinction between internalism and externalism.
Points of View and Practical Reasoning

(1982). Points of View and Practical Reasoning. Canadian Journal of Philosophy: Vol. 12, No. 2, pp. 321-333.
HIGH-VELOCITY GAS IN THE KLEINMANN-LOW NEBULA

ABSTRACT New observations of the high velocity CO emission and near infrared H 2 lines in the Orion Kleinmann-Low nebula are described. The CO emission which is detected out to ± 50 km s −1 from the line centre is characterized by low opacity (τ ≤ 2) and an angular diameter of only 37” or 2.8 × 10 17 cm at 500 pc. The total mass of highvelocity gas in the core region is 15 M θ assuming 8% of the carbon is in CO. On the basis of line profile modelling and theoretical considerations, the source structure appears to be a differentially expanding envelope, possibly the result of an explosive event within the infrared cluster. The v = 1 → 0 emission of H 2 recently detected at λ = 2μ may originate from a shock heated layer where the leading edge of the expanding shell collides with the exterior molecular cloud. Measurement of the 2μ S(l) line at high spectral resolution is used to estimate that the H 2 shock velocity is less than 30 km s −1 . The mean velocity of the H 2 emission coincides precisely with that of the large Orion molecular cloud.
Section I. The Interpretation and Use of Newer Diagnostic Studies

The diagnosis and the treatment of rheumatic diseases in older people pose special problems. Degenerative joint disease, almost universally present in the elderly, may not be the basis for the newly developing rheumatic symptoms. Systemic inflammatory disease may be confused with malignancy or it may be an initial manifestation of malignancy. Some drugs used to control central-nervous-system or cardiovascular disease may produce painful rheumatic syndromes. Results of laboratory tests used in the diagnosis of rheumatic diseases may be altered by other nonrheumatic disorders in older people. Papers in this symposium will explore these concepts in greater detail.
Low k-factor and low density HCFC-141b appliance foam

HCFC-141b blown rigid foams have now been used successfully for a couple of years in North America as insulation in refrigerated home appliances. Manufacturers have had time to adjust to the differences in processing between these systems and the CFC-11 systems that they replaced. Many appliance manufacturers have now focused their interest on foams that will provide lower cost without sacrificing properties or processing characteristics. Although there are a number of ways to reduce cost, one of the best ways is to reduce the density of the foam. Bayer Corporation has previously reported on low density HCFC-141b appliance foam which had similar densities to CFC-11 foams of around 1.9 to 2.0 pounds per cubic foot (pcf). These foams had somewhat higher k-factors but still were successful in replacing some of the CFC-11 foams commercially. Other HCFC-141b foam systems were developed that gave equivalent or lower k-factor foams but at somewhat higher densities. These systems replaced most of the commercial CFC-11 systems. Thermal conductivity of rigid polyurethane foams is to a large extent affected by the blowing agent, the closed cell content, cell size and the density. It has been reported that there exists a minimum thermal conductivity in the density range of around 2 to 3 pcf for CFC-11 blown foams. This appears to be true also for HCFC-141b foams, although the density range maybe slightly different or narrower. It is not easy to reduce the density below 2 pcf without increasing the k-factor of the foam. Around or below 2 pcf, the increase in k-factor is caused not only by an increase in the radiation contribution to thermal conductivity due to coarser cells but to higher open cell content and possible convection currents within the cells. Since strength properties are also affected by density. There is a need by developers and manufacturers to evaluate long term dimensional stability of lower density foams. This paper will discuss the development of new low density HCFC-141b appliance foams which have similar k-factors compared to the majority of commercial appliance foam systems in the 2.1 to 2.2 pcf range. These new systems will also be shown to have substantially lower k-factors with only a slight increase in density compared to a commercial system in the 1.9 to 2.0 pcfrange. In addition, physical properties and processing characteristics of these foams will be compared to commercial foams.
Teaching Critical Thinking: Bringing the Real World into the Classroom

Educators have recently begun to stress the importance of teaching critical-thinking skills. California Executive Order Number 338 mandates that no less than nine semester hours of an undergraduate's education at a state system school be devoted to improving communication skills and critical-thinking skills (Walters 1986). The National Commission on Excellence in Education (1983) recommended that all subject matter areas should try to develop critical-thinking skills. Throughout the nation, programs to teach critical-thinking skills are being implemented from grade school to the college level. For example, undergraduate schools such as Bloomfield College (Sadler and Whimbey 1985), the University of Louisville (Blum and Spanghel 1979) and Bowling Green University (Woditsch 1978) have instituted formal programs. Programs on the elementary levels include Lipman's (1985) Philosophy for Children, Feuerstein's (1980) Instrumental Enrichment, and the Chicago Mastery Learning Project (Jones 1982). Though many programs are being developed, a number of controversies exist regarding instruction in criticalthinking skills. The major controversies include defining the skills to be taught and designing instructional delivery systems that promote the generalized use of these skills.
The Acoustic Environment of the NASA Glenn 9- by 15-foot Low-Speed Wind Tunnel

The 9- by 15-Foot Low Speed Wind Tunnel is an acoustic testing facility with a long history of aircraft propulsion noise research. Due to interest in renovating the facility to support future testing of advanced quiet engine designs, a study was conducted to document the background noise level in the facility and investigate the sources of contaminating noise. The anechoic quality of the facility was also investigated using an interrupted noise method. The present report discusses these aspects of the noise environment in this facility.
Video compression for portable communication using pyramid vector quantization of subband coefficients

The authors describes a video compression scheme that performs pyramid vector quantization (PVQ) of subband coefficients and a VLSI architecture for the PVQ decoder. This algorithm not only provides good compression performance, but also results in a low complexity, low power VLSI implementation. Furthermore, this algorithm demonstrates good error resiliency under severe channel distortion without the use of error correction codes. PVQ also allows encoding and decoding to be computation-based instead of memory-based, as in standard VQ, thus allowing for real-time video coding and eliminating the need for large memories. The algorithm and its performance are described in detail, and the chip architecture of the PVQ decoder is presented. >
Multiple synaptic and membrane sites of anesthetic action in the CA1 region of rat hippocampal slices

Background Anesthesia is produced by a depression of central nervous system function, however, the sites and mechanisms of action underlying this depression remain poorly defined. The present study compared and contrasted effects produced by five general anesthetics on synaptic circuitry in the CA1 region of hippocampal slices.
Reliability of Calculated Low-Density Lipoprotein Cholesterol

Aggressive low-density lipoprotein cholesterol (LDL-C)–lowering strategies are recommended for prevention of cardiovascular events in high-risk populations. Guidelines recommend a 30% to 50% reduction in at-risk patients even when LDL-C concentrations are between 70 and 130 mg/dl (1.8 to 3.4 mmol/L). However, calculation of LDL-C by the Friedewald equation is the primary laboratory method for routine LDL-C measurement. We compared the accuracy and reproducibility of calculated LDL-C F values
Mechanism of cytotoxicity mediated by the C31 fragment of the Amyloid Precursor Protein

Abstract The cytoplasmic tail of the amyloid precursor protein (APP) contains two putatively cytotoxic peptides, Jcasp and C31, derived by caspase cleavage of APP. Jcasp is a fragment starting from the e-secretase site to position 664, while C31 is a fragment from position 665 to the C-terminus. Our studies now showed that compared to C31, Jcasp appeared to play a minor role in cytotoxicity. In particular, inhibition of Jcasp generation by treatment of γ-secretase inhibitor did not lead to any attenuation of C31-induced toxicity. Secondly, because C31 toxicity is largely absent in cells lacking endogenous APP, we determined, using a split β-galactosidase complementary assay to monitor protein–protein interactions, the presence of APP associated complexes. Our results demonstrated that both APP homomeric and C31/APP heteromeric complexes were correlated with cell death, indicating that C31 complexes with APP to recruit the interacting partners that initiate the signals related to cellular toxicity.
The Relative Brauer Group of an Affine Double Plane

We study algebra classes and divisor classes on a normal affine surface of the form z 2 = f(x, y). The affine coordinate ring is T = k[x, y, z]/(z 2 − f), and if R = k[x, y][f −1] and S = R[z]/(z 2 − f), then S is a quadratic Galois extension of R. If the Galois group is G, we show that the natural map H1(G, Cl(T)) → H1(G, Pic(S)) factors through the relative Brauer group B(S/R) and that all of the maps are onto. Sufficient conditions are given for H1(G, Cl(T)) to be isomorphic to B(S/R). The groups and maps are computed for several examples.
The performance of steady-state harmonic magnetic resonance elastography when applied to viscoelastic materials

Purpose: The clinical efficacy of breast elastography may be limited when the authors employ the assumption that soft tissues exhibit linear, frequency-independent isotropic mechanical properties during the recovery of shear modulus. Thus, the purpose of this research was to evaluate the degradation in performance incurred when linear-elastic MR reconstruction methods are applied to phantoms that are fabricated using viscoelastic materials. Methods: To develop phantoms with frequency-dependent mechanical properties, the authors measured the complex modulus of two groups of cylindrical-shaped gelatin samples over a wide frequency range (up to 1 kHz) with the established principles of time-temperature superposition (TTS). In one group of samples, the authors added varying amounts of agar (1%–4%); in the other group, the authors added varying amounts of sucrose (2.5%–20%). To study how viscosity affected the performance of the linear-elastic reconstruction method, the authors constructed an elastically heterogeneous MR phantom to simulate the case where small viscoelastic lesions were surrounded by relatively nonviscous breast tissue. The breast phantom contained four linear, viscoelastic spherical inclusions (10 mm diameter) that were embedded in normal gelatin. The authors imaged the breast phantom with a clinical prototype of a MRE system and recovered the shear-modulus distribution using the overlapping-subzone-linear-elastic image-reconstruction method. The authors compared the recovered shear modulus to that measured using the TTS method. Results: The authors demonstrated that viscoelastic phantoms could be fabricated by including sucrose in the gelation process and that small viscoelastic inclusions were visible in MR elastograms recovered using a linear-elastic MR reconstruction process; however, artifacts that degraded contrast and spatial resolution were more prominent in highly viscoelastic inclusions. The authors also established that the accuracy of the MR elastograms depended on the degree of viscosity that the inclusion exhibited. Conclusions: The results demonstrated that reconstructing shear modulus from other constitutive laws, such as viscosity, should improve both the accuracy and quality of MR elastograms of the breast.
Promotion of Pt/γ-Al2O3 by New Pretreatment for Low-Temperature Preferential Oxidation of CO in H2 for PEM Fuel Cells

The hydrogen-rich reformate used as a feed to polymer electrolyte fuel cells (PEFC) must contain less than 10 ppm CO since it poisons the Pt anode. The concentration of CO leaving the water–gas shift reactor is typically around 1 mol%, which is set by thermodynamic equilibrium. One method to remove the CO is by preferential oxidation (PROX) using O2 over a (typically) Pt catalyst while minimizing the amount of H2 oxidized. The activity and selectivity of this reaction were improved by a new pretreatment method for a 5 wt% Pt/γ-Al2O3 catalyst. The pretreatment involved saturating the reduced catalyst with water and allowing it to vaporize during reduction. The improvement is attributed to a reduction in size of the metallic Pt particles as measured by XRD and TEM.
Axial Length Measurement: PalmScan Versus IOLMaster.

OBJECTIVE To compare axial length measurements taken on the handheld Micro Medical Devices (MMD) PalmScan with those taken with the Carl Zeiss Meditec IOLMaster. METHODS Sixty subjects had IOLMaster performed by a single operator to measure axial length in both eyes. Subjects then had axial length measurements taken by a different single operator with the MMD device. Each operator was masked to the other's results. Independent statistical analysis was performed to compare results. RESULTS Sixty subjects had both eyes measured with each device for a total of 120 eyes. Subjects were categorized into 1 of 3 groups with 20 subjects each, 40 eyes in each group. Subjects in group A were wearers of overnight corneal reshaping, group B were soft lens wearers, and group C were noncontact lens wearers. Overall, the measures of axial length from IOLMaster and MMD were highly correlated (correlation = 0.93, P < 0.001, n = 120). Similarly, measures within each group between the 2 methods were highly correlated: group A (correlation = 0.94, P < 0.0001, n = 40), group B (correlation = 0.90, P < 0.0001, n = 40), and group C (correlation = 0.98, P < 0.001, n = 40). Results were highly correlated between the two devices. Data scatter plots and Bland-Altman plots were generated, showing that although there was good agreement between the methods, the MMD almost always measured the axial length smaller than the IOLMaster (median difference = 0.21 mm, mean difference ± SD = 0.26 ± 0.42 mm). CONCLUSIONS The MMD is a convenient, reliable, and portable device to measure axial length. It can be used to monitor axial length in patients over time.
Goodness-of-fit test statistics that dominate the Kolmogorov statistics

Two statistics are proposed for the simple goodness-of-fit problem. These are derived from a general principle for combining dependent test statistics that has been discussed elsewhere by the authors. It is shown that these statistics are relatively optimal in the sense of Bahadur efficiency and consequently, are more efficient than any weighted Kolmogorov statistic at every alternative. A curious pathology occurs: Under certain alternatives, the sequence of statistics has a Bahadur efficacy or exact slope only in the weak sense of convergence in law.
The balance between online web site usability and providing content

Purpose – The purpose of this paper is to provide basic and practical suggestions for obtaining a balance between online web site ease of use and comprehensive online content.Design/methodology/approach – The approach is to show how library administrators can prepare for achieving a balance of providing the online content users need, while still striving to make their library web site user‐friendly.Findings – Librarians may find that they need to change their mind‐set of web site design having comprehensive information and instead focus on a streamlined, clean‐looking web site that gets their patrons to their resources as fast as possible, especially in lieu of mobile devices which are becoming so popular. Librarians may also need to change their personal approach towards vendors, patrons, as well as their own staff.Originality/value – The value of this paper is in its list of practical and interpersonal suggestions for obtaining a balance of web site usability and comprehensive online content, and relayi...
An industrial engineering technique applied to pest management

Abstract Simulation of continuous systems has become a widely used tool for design and analysis in Industrial Engineering. This paper presents an application of the technique and the concept of systems dynamics to predict the status of bark beetle infestation in southern pine forests and to provide an estimate of subsequent timber loss. Such predictions are vital to the formulation of effective strategies for pest management.
A Delayed Time of the Peak Tricuspid Regurgitation Signal : Marker of Right Ventricular Dysfunction

ABSTRACT Background Worsening degrees of tricuspid regurgitation (TR) have been associated with worse outcomes. We investigated the time it takes for the TR jet to attain its maximum peak (tmpTR) with measures of right ventricular (RV) function. Methods Several echocardiographic variables of RV size and function and tmpTR corrected for heart rate were collected from 140 patients (mean age 57 ± 20 years). Results Mean RV end systolic (15 ± 9 cm 2 ) and end diastolic (25 ± 9 cm 2 ) areas, RV fractional area change (44 ± 19%), maximal tricuspid annular motion (1.98 ± 0.71 cm), pulmonary artery systolic pressure (57 ± 33 mm Hg) and tmpTR (248 ± 75 ms). A negative correlation was seen between tmpTR and RV fractional area change ( r = −0.74; P r = −0.69; P P 240 ms identified RV systolic dysfunction (sensitivity 79% and specificity 94%, areas under the curves 0.923, P = 0.0001). The longest tmpTR values were seen in patients with both RV systolic dysfunction and pulmonary hypertension (310 ± 30 ms, P Conclusion A delayed time to peak of the maximum TR jet correlates with RV dysfunction. Patients with normal RV function and no pulmonary hypertension had abnormal tmpTR values (243 ± 57 ms) implying an underlying RV mechanical abnormality that requires further investigation.
Decomposability of symmetric multilinear functions

Let V denote a finite dimensional vector space over a field K of characteristic 0, let Tn(V) denote the vector space whose elements are the K-valued n-linear functions on V, and let Sn(V) denote the subspace of Tn(V) whose members are the fully symmetric members of Tn(V). If Ln denotes the symmetric group on {1,2,…,n} then we define the projection PL : Tn(V) → Sn(V) by the formula (n!)−1Σσ ϵ Ln Pσ, where Pσ : Tn(V) → Tn(V) is defined so that Pσ(A)(y1,y2,…,yn = A(yσ(1),yσ(2),…,yσ(n)) for each A ϵ Tn(V) and yi ϵ V, 1 ⩽ i ⩽ n. If xi ϵ V∗, 1 ⩽ i ⩽ n, then x1⊗x2⊗ … ⊗xn denotes the member of Tn(V) such that (x1⊗x2· ⊗ ⋯ ⊗xn)(y1,y2,…,yn) = Пni=1xi(yi) for each y1 ,2,…,yn in V, and x1·x2… xn denotes PL(x1⊗x2⊗ … ⊗xn). If B ϵ Sn(V) and there exists x i ϵ V∗, 1 ⩽ i ⩽ n, such that B = x1·x2…xn, then B is said to be decomposable. We present two sets of necessary and sufficient conditions for a member B of Sn(V) to be decomposable. One of these sets is valid for an arbitrary field of characteristic zero, while the other requires that K = R or C.
Plate tectonics and the problem of anthropoid origins

Using plate tectonic theory, geologic and geophysical determinants of South Atlantic opening are assessed during the Cretaceous through the Oligocene (approximately 135–25 m.y.B.P.). This is done to evalute the feasibility of statements on paleontologic and neontologic distributional data that relate to African and South American separation as the South Atlantic was created. In particular, the question of anthropoid origins is examined in light of plate tectonic theory, and the idea that monophyly of the anthropoid grade is supported by continental drift is refuted. When geological and geophysical evidence is examined in detail, the occurrence of Tertiary transfer of primates between Africa and South America is improbable. Thus one must look to either North America or Middle America for the ancestors of the platyrrhines, and to Eurasia for the ancestors of the catarrhines. The problem of whether those ancestors were prosimians or anthropoids is not dealt with, because the question of whether the Platyrrhini and the Catarrhini are independently evolved from prosimian ancestors (anthropoid diphyly) or are evolved from ancestors that were already of an anthropoid level of structural organization (anthropoid monophyly) can only be resolved on biological grounds and at a level of analysis that allows one to distinguish between analogies developed in parallel, homologies caused by symple-siomorphy, and homologies caused by synapomorphy.
Biko, Black Consciousness, and ‘the System’ eZinyoka: Oral History and Black Consciousness in Practice in a Rural Ciskei Village

ABSTRACT Part of a larger research project on the community development programmes of the Black Consciousness movement (1969–1977), this article focuses on the relationship between the Zanempilo Community Health Centre and the people of Zinyoka, the village where Zanempilo operated. The article begins with an overview of community work within the Black Consciousness movement and the formation of the Black Community Programmes (BCP) organisation. It then follows Steve Biko to King William's Town, where he established a branch of the BCP. The article turns to Zinyoka as it explains why and when Zanempilo was built there and analyses its influence on the community. Drawing upon oral history interviews of Zinyoka residents and BCP employees, it argues that Black Consciousness action in the form of the clinic physically and economically improved Zinyoka, if only temporarily, and instilled a sense of human dignity in the residents. Situating this story in Zinyoka brings into relief the dynamics of Ciskei politi...
Amyloidosis and Alzheimer's disease.

Alzheimer's disease (AD) is the most frequent type of amyloidosis in humans and the commonest form of dementia. Extracellular Abeta amyloid deposits in the form of amyloid plaques and cerebral amyloid angiopathy as well as intraneuronal neurofibrillary tangles co-exist in the brain parenchyma of AD patients, the cognitive areas being the most severely affected. This review focuses on the potential role of amyloid in the development of neurodegeneration and presents studies of AD and other unrelated inherited dementia syndromes associated with neuronal loss and amyloid deposition in the brain.
Flow dynamics of Byrd Glacier, East Antarctica

Force-balance calculations on Byrd Glacier, East Antarctica, reveal large spatial variations in the along-flow component of driving stress with corresponding sticky spots that are stationary over time. On the large scale, flow resistance is partitioned between basal (~80%) and lateral (~20%) drag. Ice flow is due mostly to basal sliding and concentrated vertical shear in the basal ice layers, indicating the bed is at or close to the pressure-melting temperature. There is a significant component of driving stress in the across-flow direction resulting in nonzero basal drag in that direction. This is an unrealistic result and we propose that there are spatial variations of bed features resulting in small-scale flow disturbances. The grounding line of Byrd Glacier is located in a region where the bed slopes upward. Nevertheless, despite a 10% increase in ice discharge between December 2005 and February 2007, following drainage of two subglacial lakes in the catchment area, the position of the grounding line has not retreated significantly and the glacier has decelerated since then. During the speed-up event, partitioning of flow resistance did not change, suggesting the increase in velocity was caused by a temporary decrease in basal effective pressure.
Usability Analysis of Learning Environments — Needs and Realities:

This paper addresses the question of whether the application of principles and methods of usability analysis can benefit the design of learning environments, and can thereby benefit student learning. The application of principles and practices of usability and ergonomic analysis have achieved proven success in improving performance of many sociotechnical systems areas. However, the benefits that the application of HF/E science might bring to promoting educational system and student learning performance have yet to be widely recognized. On the assumption that such recognition may someday be realized, an analysis is offered of the comparative advantages and disadvantages of ergonomic program intervention, versus usability analysis, for purposes of improving the design quality of K–12 learning environments. Usability analysis may provide benefits in terms of flexibility of application, ease of implementation, and student learning gains. The true test of applying HF/E science as a meaningful strategy to benef...
Modulation of HeLa cells spreading by the non-receptor tyrosine kinase ACK-2

The CDC42 regulated non-receptor tyrosine kinase ACK-2 has been associated with integrin signaling. In this report, the effect of ACK-2 on the modulation of cell spreading and motility was examined. HeLa cells expressing epitope-tagged wild type ACK-2 showed a slower rate of spreading on fibronectin when compared with untransfected cells. An ACK-2 protein lacking its SH3 domain was still capable of modulating HeLa cell spreading suggesting that its tyrosine kinase activity is sufficient to induce the observed phenotype. The ACK-2 effect on the rate of cell spreading did not involve inhibition of integrin-mediated activation of PI-3K signaling, since it did not alter membrane translocation of a GFP-PH-AKT domain (AKT pleckstrin homology domain) used as a reporter for PI-3K products induced by cell adhesion. The ACK-2 effect appears to be upstream from the adapter protein CrkII, since co-expression of CrkII and ACK-2 results in a neutralization of ACK-2 mediated effects on HeLa cell spreading. Similarly, co-expression of p130Cas, which interacts with the adapter protein CrkII, with ACK-2, also results in a partial reversion of the ACK-2 effects on cell spreading. CrkII mediated reversal of the ACK-2 induced phenotype requires the activity of the small GTPase, Rap1. Co-expression of ACK-2 and CrkII with a dominant negative form of Rap1 reverses the neutralization by CrkII suggesting that CrkII mediated activation of Rap1 is required. However, an active form of Rap1 is not sufficient to reverse the ACK-2 phenotype by itself. A role for Rac1 in ACK-2 effects was also established. An activated Rac1 protein neutralized the ACK-2 mediated inhibition of cell spreading. A direct measurement of cell motility by either a modified Boyden chamber or wounding assay demonstrates that ACK-2 overexpression increases the motility of the cells. These results suggest that ACK-2 modulates HeLa cells spreading upstream of pathways regulated by CrkII and that ACK-2 may regulate cell motility by controlling the activation of small GTPases such as Rap1 and Rac1. J. Cell. Biochem. 84: 655–665, 2002. © 2001 Wiley-Liss, Inc.
Microstructural changes in eutectic tin–lead alloy due to severe bending

Severe plastic deformation in an eutectic tin-lead alloy is studied by imposing fast bending at room temperature, in an attempt to examine the microstructural response in the absence of thermally activated diffusion processes. A change in microstructure due to this purely mechanically imposed load is observed: the tin-rich matrix phase appears to be extruded out of the narrow region between neighboring layers of the lead-rich phase and alterations in the colony structure occur. A micromechanism is proposed to rationalize the experimental observations.
Neuroglobin protects PC12 cells against oxidative stress.

Abstract Neuroglobin (Ngb) is a newly discovered globin in the vertebrate brain that exhibits neuroprotection against hypoxic/ischemic injury. Hypoxic/ischemic brain injury is associated with accumulation of reactive oxygen species (ROS) and/or reactive nitrogen species (RNS), and antioxidants or ROS scavengers promote cell survival. Therefore, Ngb may serve as a scavenger of toxic reactive species, such as hydrogen peroxide. To examine the anti-oxidative role of neuroglobin, PC12 cells were transfected with wild type and mutant (H64 V/H96A) Ngb for 48 h and then treated with H2O2 (0.1, 0.2 and 0.4 mM) for 6 h. Ngb siRNA decreased the H2O2-induced Ngb expression and exacerbated H2O2-induced cell injury. Transient transfection of Ngb induced dose-dependent increases in Ngb protein expression and did not alter SOD, GPX, and catalase activities. Overexpression of wild type Ngb, but not of mutant Ngb, significantly attenuated H2O2-induced ROS/RNS accumulation and lipid peroxidation, decreased H2O2-induced mitochondrial dysfunction and apoptosis, and promoted overall cell survival. Thus, Ngb plays a protective role against oxidative stress, which appears to be primarily mediated by intrinsic Ngb antioxidant properties.
On the subtropical frontal zone north of Hawaii during winter

Abstract Oceanic fronts in the subtropical frontal zone north of Hawaii are investigated and related to atmospheric forcing. Particular attention is paid to the winter of 1974 when a detailed study was made of the thermohaline structure aboard the R.V. Thomas G. Thompson. In that winter, well-defined fronts occurred at 34, 31 and 28°N. In the upper 100 m, these fronts are nearly vertical and are characterized by temperature, salinity and sound velocity gradients of up to 2°C (27 km)−1, 0.3‰ (27 km)−1 and 12 m s−1 (27 km)−1, respectively. Horizontal density gradients across the northern two fronts are small because of compensating horizontal temperature and salinity gradients. A thin layer of increased stability is encountered between 100 and 125 m. Below this layer, there are prominent lateral intrusions of cool and low-salinity subsurface water under warmer and higher salinity surface water, at latitudes north of 31°N and longitudes east of 155°W. The 0/1500 db dynamic height topography bears no similari...
Whispering-Mode Waveguide

Properties of a relatively new type of waveguide structure of potential use for confining infrared radiation to a small mode volume over long path lengths are reviewed. A single guiding surface with curvature radius p and bend radius R allows propagation of a near-grazing incidence "whispering mode" of transverse width ≈ (λρR/π)1/2 and radial width ≈ 1/2 (λ2R)1/3. For sufficiently large p, the loss per revolution for TE-mode propagation is π AN, where AN is the normal-incidence reflection loss. Results on a number of prototype structures in general agreement with these considerations are described.© (1981) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Generative and Regulative Organization in Site-and-Services Housing Projects A Case from Oaxaca, Mexico

Housing is a major area where government regulative planning affects the lives of people from every socioeconomic class. This article examines the planning style (regulative) of a government agency organizing a site-and-services project in Oaxaca, Mexico and compares it to the situational response style (generative) of the community's residents. In most cases the style of planning used by community residents puts them at a disadvantage when faced with an organized plan pushed by outside change agents, [housing, planning, Oaxaca]
Cognitive multi-antenna radar detection using Bayesian inference

We consider a cognitive multi-antenna radar system that is capable of adjusting radar waveforms for iterative transmission based on prior radar scattering channel information. We formulate the cognitive target detection problem. The performance of the detection algorithm by matched illumination is tested using numerical examples and is compared with the time reversal waveforms. The detection results demonstrate the success of the algorithm.
Autoregulation of Release of Melanocyte Stimulating Hormone from the Rat Pituitary

MELANOCYTE stimulating hormone (MSH) enables amphibians such as the frog to change skin colour and thereby adapt to the environment. The function of this pituitary hormone in mammals such as the albino rat has not been established.
Substrate and underlayer dependence of sub-32nm e-beam HSQ pillar patterning process for RRAM application

High AR bi-layer resist (BLR) pillar with organic underlayer (UL) is inevitable for etching of thick RRAM film stacking considering etch selectivity to avoid collapse. Selection of UL is a key factor to determine the AR of BLR pillar and selectivity during etching of hard mask (HM) and RRAM film stacking. In this work, e-beam patterning of HSQ pillar under various e-beam dose conditions, pattern density and HSQ thicknesses are studied on carbon highly contained UL TBLC-100PM. Hard mask layer of low temperature nitride (LTN) or oxide (LTO) above TiN/Ti/HfOx RRAM film stacking are also studied for achieving highest HSQ CD resolution by reducing e-beam proximity effect. Fogging effect is studied with various e-beam dose of the L/S=1/20 isolated pillar array which is far from the other arrays of 36 μm. Experimental results are summarized below. Etch rates (etch resistance) of TBLC-100PM UL under fluorine or chlorine-based plasmas are lower (higher) than that of AR3-600 UL with low carbon contained. Thicker LTN HM is necessary for higher HSQ pillar CD resolution. HSQ pillar CD resolution on LTO HM is higher than that on LTN HM. Smallest CD of HSQ pillar is 23.1 nm. Fogging effect is strong for TBLC-100PM where e-beam dose could affect the shape of HSQ pillar of neighboring array. This is not observed for AR3-600 UL. HSQ pillar CD resolution is highest for HSQ coated at 2000 rpm. Small change of HSQ coating speed could degrade CD resolution and imaging contrast drastically which may come from the fogging effect.
Ventriculo-gallbladder shunts in children

Ventriculoperitoneal shunts are the most common procedure for the treatment of hydrocephalus. Ventriculoatrial shunts are effective but are subject to a higher incidence of potentially serious complications. We report our experience with ventriculo-gallbladder shunts in children. Ventriculo-gallbladder shunts are safe, effective, and technically easy to perform. We recommend their use when ventriculoperitoneal shunts have failed or the peritoneal cavity is not adequate for shunting.
Quartic ghost interactions of O(N) supergravity

Abstract The quartic ghost couplings of O(N) (N ⩽ 8) supergravity are obtained to order κ2. These additional interactions which are necessary for unitarity are formally the same for all N. This pattern may be useful in the search for auxilliary fields of O(N > 2) supergravity.
Teaching Combined Methods: The Upside

This article describes how the perspectives of physical education and elementary education majors on physical education teaching changes as a result of attending a combined Methods of Teaching Elementary Physical Education course.
Feasibility and preliminary accuracy of high-resolution imaging of the liver and pancreas using FNA compatible microendoscopy (with video)

Background EUS-guided FNA is one of the few techniques that can obtain cells and tissue from the liver and pancreas. However, the technique remains vulnerable to poor specimen quality and sampling error. Objective To evaluate the ability of a high-resolution microendoscope (HRME) to visualize the cellular and architectural features of normal and malignant liver and pancreatic tissue ex vivo, to assess the ability of endosonographers to identify normal and neoplastic tissue by using HRME images, and to demonstrate preliminary technical feasibility of in vivo HRME imaging via EUS fine-needle puncture (FNP). Design Ex vivo pilot feasibility study in human tissue; in vivo swine model. Setting Two academic medical centers. Patients Co-registered HRME images and biopsies were obtained from surgically resected hepatic and pancreatic tissues from 44 patients. Intervention Images were divided into training (12 images) and test (80 images) sets containing a range of normal and pathologic conditions for each organ. After viewing the training sets, 9 endosonographers attempted to distinguish malignant tissue from normal or benign lesions in the test sets, each of which contained 40 unique images with individual diagnoses from pathology. Main Outcome Measurements Image acquisition feasibility, ex vivo and in vivo. Ability of endosonographers to recognize features of normal/benign or malignant tissue from the liver and pancreas. Results Overall, the 9 endosonographers achieved median accuracy figures of 85% in the liver and 90% in the pancreas. The endosonographers with prior experience in reading HRME images achieved accuracy rates between 90% and 95%. Technical feasibility of HRME imaging through a 19-gauge EUS-FNP needle was demonstrated in an in vivo swine model. Limitations Ex vivo study. Conclusion High-resolution microendoscopy allows real-time imaging of cellular-level morphology and tissue architecture in the liver and pancreas. The technique appears to have a short learning curve, after which endosonographers achieved high accuracy rates in distinguishing malignant tissue from normal and benign pathology in both organs. Translating this imaging platform to the in vivo setting appears technically feasible.
Non-Fermi-liquid behavior in a Heisenberg chain with impurities

Abstract The Takhtajan–Babujian chain of spin S interacting with a finite concentration c of impurity spins S′ is solved by means of Bethe's Ansatz. The ground state is studied as a function of c, the magnetic field and the coupling of the impurities to the lattice. In particular a crossover from Fermi-liquid to non-Fermi-liquid behavior is found.
Metabolic images from dynamic positron emission tomography studies

A dynamic sequence of positron emission tomography (PET) images gives rise to the possibility of creating images of in vivo tissue metabolism. For this reason PET is potentially a valuable instrument in the study of human biology and medicine. The analysis of dynamic PET data to produce metabolic images is a challenging problem from a statistical point of view. For example, a typical data set arising in the study of cerebral glucose utilization has on the order of 30 time-binned images per cross-sectional slice of tissue under examination, each of dimension 128 x 128 pixels. Metabolic imaging requires that the time series at each pixel, known as the time activity curve (TAC), be analysed to produce an estimate of local metabolism. This paper describes a mixture analysis approach to the construction of such metabolic images. In the approach the TAC at a given pixel is expressed as a weighted sum of sub-TACs corresponding to homogeneous tissues represented at the pixel. Estimates of tissue metabolism at the pixel are then constructed as a weighted sum of the metabolism associated with the individual sub-TACs. The procedure is illustrated by application to a [F-18]-labelled deoxyglucose study in a patient with a brain tumour. The ability to map simultaneously a range of parameters related to the transport and biochemical transformation of the radio-tracer, demonstrates the potential power of dynamic PET.
Physical Principles of Exploration Methods

The subtitle of this book An Introductory Text for Geology and Geophysics Students, is appropriate. Beck has achieved his goal of providing a useful textbook for an introductory undergraduate course in exploration geophysics with an emphasis on basic physical principles. The remarkable aspect of this book is that the fundamental physics of geophysical exploration is explained in a very readable fashion without overwhelming the student mathematically because derivations do not go beyond basic calculus. Furthermore, the importance of geology and rock properties to planning and interpreting geophysical measurements are not lost in the discussion of the physics of the problem.
Density of states and resistive transitions in the fluctuation regime above Tc

Abstract We present data on the rounding of the resistive transition for granular Al and the corresponding electronic density of states (EDS) as determined from tunneling measurements. We find that the EDS of the granular Al in the fluctuation regime is depressed from the normal state value over a small energy range Ec(T) centered about the Fermi level. From the values of Ec(T), we are able to estimate the decay rate Γ(T)/h of fluctuations in the Cooper pair density. The values of Γ(T) determined from tunneling measurements agree with the theoretical prediction only over a limited temperature range.