cssi/SciSciGPT-SciSciNet huggingface dataset:
Polyamines and nonmelanoma skin cancer

Elevated levels of polyamines have long been associated with skin tumorigenesis. Tightly regulated metabolism of polyamines is critical for cell survival and normal skin homeostasis, and these controls are dysregulated in skin tumorigenesis. A key enzyme in polyamine biosynthesis, ornithine decarboxylase (ODC) is upregulated in skin tumors compared to normal skin. Use of transgenic mouse models has demonstrated that polyamines play an essential role in the early promotional phase of skin tumorigenesis. The formation of skin tumors in these transgenic mice is dependent upon polyamine biosynthesis, especially putrescine, since treatment with inhibitors of ODC activity blocks the formation of skin tumors and causes the rapid regression of existing tumors. Although the mechanism by which polyamines promote skin tumorigenesis are not well understood, elevated levels of polyamines have been shown to stimulate epidermal proliferation, alter keratinocyte differentiation status, increase neovascularization, and increase synthesis of extracellular matrix proteins in a manner similar to that seen in wound healing. It is becoming increasingly apparent that elevated polyamine levels activate not only epidermal cells but also underlying stromal cells in the skin to promote the development and progression of skin tumors. The inhibition of polyamine biosynthesis has potential to be an effective chemoprevention strategy for nonmelanoma skin cancer.
Elsevier Compendex and Google Scholar: A Quantitative Comparison of Two Resources for Engineering Research and an Update to Prior Comparisons

Elsevier's Compendex product (and its ancestor, Engineering Index) has been a de rigeur indexing tool for searching the primary literature in engineering for many years. However, the price of Compendex continues to rise while at the same time, broader, lower-cost or even free alternatives to such expensive indexing tools have proliferated. This paper seeks to quantitatively and, to a lesser extent, qualitatively compare Compendex to Google Scholar. In this paper, the author used a combination of methodologies in prior comparisons of both Google Scholar and Compendex to other indexing services and to each other. We undertook a quantitative comparison of the retrieval capabilities of the two indexing tools with the specific aim of examining Google's suitability to be a primary indexing tool for engineering literature. The author also considered additional factors regarding the ease-of-use and ‘added value’ features of the two interfaces.
Race Differences in Union Transitions among Cohabitors: The Role of Relationship Features

Using data from the first two waves of the National Survey of Families and Households, we analyze union transitions among cohabitors (n = 456) to determine whether relationship features, including relationship quality, marital expectations, and relationship duration, account for race differences in union outcomes. Black cohabitors are much less likely than Whites to marry but are more likely to remain cohabiting. Although the inclusion of relationship features does not eliminate the race difference in transitions to marriage, the effect of relationship happiness on cohabitors' union outcomes operates differently for Blacks and Whites. Specifically, relationship happiness encourages marriage only among Whites.
AMP-deaminases from avian brain and muscle: catalytic and immunological differences.

Abstract 1. 1. Purified adenylic acid deaminases from brain and breast muscle of adult chickens have been compared with respect to activation by ATP, substrate specificity and the effect of anti-breast muscle deaminase serum on enzyme activity. 2. 2. Both deaminases are activated by ATP; the effect is most pronounced on the brain enzyme. 3. 3. Although the brain and muscle deaminases will utilize deoxy-AMP, in addition to AMP, as a substrate, the ribonucleotide is deaminated at a faster rate. The brain enzyme is most specific. 4. 4. Rabbit anti-breast muscle deaminase serum strongly inhibits muscle adenylate deaminase but has no effect on the enzyme from brain.
GENDER PATTERNS IN COLLEGE STUDENTS' CHOICES OF THEIR BEST AND WORST PROFESSORS

Students (N = 175) at a large public university described their best and worst professors. Male students chose a female professor as “best” less often than expected whereas female students chose a ...
Speech-Language Hearing Interventions in the Schools: A Public Health Perspective on Measuring Their Short-Term and Long-Term Impact

Prevalence of studies of speech, language, and hearing disorders do not yet adequately define the frequency of specific communication disorders in children. Such data are needed to provide a strong...
Variability of summer cloudiness in the Arctic Basin

The extent and thickness of clouds in the Arctic Basin varied considerably in space and time in the late springs and summers of 1977–1979. While, on the average, clouds covered two thirds or more of the basin at any one time, cloud-free episodes were particularly common from the middle of June to late July and persisted locally for several days or even weeks. The central Arctic was less cloudy than the ocean zones closer to the coast in spring, but more cloudy in summer. Most clouds were semi-transparent, allowing recognition of underlying surface features. Optically thick clouds with middle and high level tops were associated with low pressure systems and with atmospheric flows from lower latitudes at the surface and aloft. Cloud-free skies were most frequent in high pressure cells. Climate models used to assess the impact of CO2 and other trace gases on the radiation budget in the high latitudes should account for the heterogeneity of cloud extent and thickness in the Arctic Basin.
Self-dual Yang-Mills as a totally integrable system

The characteristics of a totally integrable system for the self-dual Yang-Mills equations are pointed out: the Parametric Bianchi-Backlund transformations, infinite conservation laws, the corresponding linear systems, and the infinite dimension Kac-Moody algebra.
Dimensionality-Driven Insulator-to-Metal Transition in the Bechgaard Salts

Optical experiments were conducted on a series of organic linear chain conductors with different values of the interchain single-electron transfer integral tb, which quantifies the degree of anisotropy. Electron-electron interactions together with Umklapp scattering resulted in a correlation gap and an insulating state for small tb. An insulator-to-metal transition was observed whentb exceeded a critical value, on the order of the correlation gap Egap. The absence of a plasma edge on the insulator side of the transition for polarization perpendicular to the chains suggests that the electrons are confined to the chains. The optical features of the metallic state, when contrasted with the magnetic properties, are suggestive of spin-charge separation.
Thermally driven atmospheric escape: Monte Carlo simulations for Titan's atmosphere

Abstract Recent models of Titan's upper atmosphere were used to reproduce the Cassini measurements of the density vs. altitude by allowing a net upward flow at the exobase. Large mass flow rates were extracted and interpreted due to thermally driven escape to space at a rate that is orders of magnitude larger than the Jeans escape rate. This process is referred to as slow hydrodynamic escape. Direct simulation Monte Carlo (DSMC) models are used here to describe the transition region of Titan's atmosphere where the gas changes from being dominated by collisions to being dominated by ballistic transport. When normalized at an altitude below the exobase to the densities and temperatures calculated in the recent continuum descriptions of the Cassini ion neutral mass spectrometer data, these simulations show no evidence for slow hydrodynamic escape. In addition, above the nominal exobase there is no evidence for the proposed enhancement in the tail of the molecular speed distribution that would be required at these temperatures to give the suggested escape rates. Even simulations at Titan for artificially small Jeans parameters do not give thermal escape rates that deviate enormously from the Jeans estimate. Therefore, we conclude that the suggested upward flow rates extracted from the INMS data, if confirmed, must be due to mass loss by non-thermal processes and/or global transport.
Analysis of Gulf of Mexico bottlenose dolphins for organochlorine pesticides and PCBs

Abstract Organochlorine concentrations were determined in blubber samples from 33 Tursiops truncatus stranded on the Texas and Florida coastlines. All tissues had measurable concentrations of 4,4'-DDE (0·18–70·7 μg/g lipid weight) and ΣPCB (4·1–149 μg/g lipid weight). Pesticide and PCB concentrations were similar to those reported in Tursiops truncatus from the Atlantic coast of the United States and the southeast coast of Africa. Organochlorine concentrations were highest in mature males, and differences in the ΣPCB/ΣDDT ratios between mature and immature males suggests a recent decrease in DDT uptake, related to the commercial DDT ban in the US in 1971, as well as dietary differences between younger and older animals. Analysis of a female and her calf indicate that females reduce their own organochlorine body burden through transplacental transfer. However, no reduction of some higher molecular weight PCBs was found. Transplacental transfer rates of 5·1% for ΣDDT and 3·7% for ΣPCB were determined based on a stranded female and her full term, unborn calf. Predictions of uptake and depuration rates of organochlorines based on gender in Tursiops truncatus agree with clearance rates from previous studies.
A nonisothermal film model for mass-transfer-limited selective epitaxial growth of silicon on patterned surfaces

Abstract A two-dimensional film model for mass-transfer-controlled selective epitaxial growth (SEG) of Si on bare and regularly patterned wafers was developed, and the effects of bulk gas composition, pressure, substrate temperature, thermal diffusion, and oxide coverage were analyzed. SEG rates decrease with a lower concentration of the source gas and with the addition of HCl, which eventually leads to etching. The effects of pressure and substrate temperature on mass-transfer-limited SEG rates are determined by the way in which the equilibrium composition at the deposition surface depends on these variables. Thermal diffusion contributes to larger net fluxes away from the deposition surface. The effect of thermal diffusion is to inhibit SEG rates at lower bulk HCl concentrations and to extend the growth region to higher bulk HCl concentrations. Higher oxide coverages produce higher deposition rates with reduced mass transfer limitations. These model predictions are qualitatively consistent with reported observations.
A pilot study of women's knowledge of pregnancy health risks: implications for contraception.

Abstract Background This study was performed to assess women's knowledge of the health risks of pregnancy and how their assessment of pregnancy risks compared to their estimates of the risks of oral contraceptives. Study Design A survey, which asked both open-ended and specific questions about the health benefits and risks of pregnancy, was administered verbally on a one-on-one basis to nonpregnant, English-speaking, reproductive-age women. Results Of the 248 women who provided information for analysis, over one quarter of women could not correctly name any health risk associated with pregnancy. When shown a list of potential health risks, only 13.3% correctly identified all the health problems that increased in pregnancy. Only 49% knew that risks of venous thromboembolism (VTE), diabetes and hypertension increase in pregnancy; 30.6% did not know that VTE risk increases. Over 75% of respondents rated birth control pills as more hazardous to a woman's health than pregnancy. The greater the women's education, the more likely she was to believe that oral contraceptives are riskier than pregnancy. Conclusion This pilot project clearly demonstrates a need to assess women's understanding of the health hazards of pregnancy on a national level. Underestimation of pregnancy risks can lead to contraceptive method discontinuation, can decrease motivation to seek preconceptional care and can lead to greater medicolegal liability for providers of obstetrical care.
Local parametric representation of displacement functions for linkages and manipulators

Abstract A Taylor series approach is used to derive a general procedure for determining an n th-order local parametric approximation to the displacement functions. It is proven that the developed approach will provide local displacement functions in the neighborhood of any regular position as well as in the neighborhood of any singular position for which a certain nonsquare augmented matrix has full rank. The computational procedure requires only the solution of systems of (nonsingular) linear equations and is illustrated for the examples of the crank-slider, RRCPRP and RCRCR linkages. The importance of the proposed approach is that it enables determination of the local behavior of the displacement functions to: (i) provide a higher-order numerical predictor for extending the displacement functions and (ii) provide the n th order instantaneous kinematics of the system in the space of motion parameters. The method can be applied to any system of N equations in N + 1 unknowns.
Accuracy of Inferring Self- and Other-Preferences from Spontaneous Facial Expressions

Participants’ faces were covertly recorded while they rated the attractiveness of people, the decorative appeal of paintings, and the cuteness of animals. Ratings employed a continuous scale. The same participants then returned and tried to guess ratings from 3-s videotapes of themselves and other targets. Performance was above chance in all three stimulus categories, thereby replicating the results of an earlier study (North et al. in J Exp Soc Psychol 46(6):1109–1113, 2010) but this time using a more sensitive rating procedure. Across conditions, accuracy in reading one’s own face was not reliably better than other-accuracy. We discuss our findings in the context of “simulation” theories of face-based emotion recognition (Goldman in The philosophy, psychology, and neuroscience of mindreading. Oxford University Press, Oxford, 2006) and the larger body of accuracy research.
Overexpression of Krüppel-like factor 4 in the human colon cancer cell line RKO leads to reduced tumorigenecity.

Kruppel-like factor 4 (KLF4) is a zinc-finger-containing transcription factor, the expression of which is enriched in the postmitotic cells of the intestinal epithelium. KLF4 is a target gene of the tumor suppressor adenomatous polyposis coli (APC). We sought to determine the role of KLF4 in suppressing the tumorigenecity of RKO colon cancer cells, which do not express KLF4. We utilized an established system in RKO cells, in which an inducible promoter controls expression of KLF4. Four independent assays were used to assess the effects of KLF4 induction on tumor cells. We find that KLF4 overexpression reduces colony formation, cell migration and invasion, and in vivo tumorigenecity. The mechanism of action of KLF4 does not involve apoptosis. These findings, along with our previous findings that KLF4 induces G1/S arrest, suggest that KLF4 is a cell cycle checkpoint protein that can reduce tumorigenecity of colon cancer cells.
In vitro predictive testing: the sulfonamide era

Since initial reports of use of a human tumor cloning system to predict response or lack of response of a patient's tumor to chemotherapy, there have been approximately 2,166 clinical correlations attempted. Overall, the percent true positives has been 69% while the percent true negatives has been 92%. Despite the high reliability of this system to predict patient response or lack of response, the cloning assay has not been put into general clinical use. Reasons for this include the past inability to grow a majority of the patients' malignancies and lack of controlled trials demonstrating an advantage of a cloning assay choice over a clinician's choice. Both of these problems are being addressed with greatly improved abilities to grow patient malignancies (70%-80% of patients' tumors can now be grown in vitro) and the reporting of results of prospectively controlled randomized trials. It is likely that the most significant limitation for the human tumor cloning assay will be the lack of agents with in vitro activity. It is proposed that we are in the "sulfonamide era" of in vitro drug sensitivity testing of human tumors. It is unlikely any predictive assay will be of major utility until a more active spectrum of agents becomes available for in vitro testing and in vivo treatment.
Metabolic Scaling in Complex Living Systems

In this review I show that four major kinds of theoretical approaches have been used to explain the scaling of metabolic rate in cells, organisms and groups of organisms in relation to system size. They include models focusing on surface-area related fluxes of resources and wastes (including heat), internal resource transport, system composition, and various processes affecting resource demand, all of which have been discussed extensively for nearly a century or more. I argue that, although each of these theoretical approaches has been applied to multiple levels of biological organization, none of them alone can fully explain the rich diversity of metabolic scaling relationships, including scaling exponents (log-log slopes) that vary from ~0 to >1. Furthermore, I demonstrate how a synthetic theory of metabolic scaling can be constructed by including the context-dependent action of each of the above modal effects. This “contextual multimodal theory” (CMT) posits that various modulating factors (including metabolic level, surface permeability, body shape, modes of thermoregulation and resource-transport, and other internal and external influences) affect the mechanistic expression of each theoretical module. By involving the contingent operation of several mechanisms, the “meta-mechanistic” CMT differs from most metabolic scaling theories that are deterministically mechanistic. The CMT embraces a systems view of life, and as such recognizes the open, dynamic nature and complex hierarchical and interactive organization of biological systems, and the importance of multiple (upward, downward and reciprocal) causation, biological regulation of resource supply and demand and their interaction, and contingent internal (system) and external (environmental) influences on metabolic scaling, all of which are discussed. I hope that my heuristic attempt at building a unifying theory of metabolic scaling will not only stimulate further testing of all of the various subtheories composing it, but also foster an appreciation that many current models are, at least in part, complementary or even synergistic, rather than antagonistic. Further exploration about how the scaling of the rates of metabolism and other biological processes are interrelated should also provide the groundwork for formulating a general metabolic theory of biology.
Cigarette Smoking and Panic Attacks Among Young Adults in the Community: The Role of Parental Smoking and Anxiety Disorders

Background The goal of the current study is to examine the association between cigarette smoking and panic attacks and panic disorder among youth and to investigate parental anxiety disorders and parental cigarette smoking in these links. Methods Data were drawn from the Oregon Adolescent Depression Project (OADP) (n = 1709). Cigarette smoking and panic attacks and panic disorder were assessed at three time points from adolescence to young adulthood. Results Daily cigarette smoking at Time 1 was associated with a significantly increased risk of panic attacks (odds ratio [OR] = 2.6 [1.3, 5.3]) and panic disorder (OR = 4.2 [2.0, 8.9]) at Time 3. After adjusting for parental anxiety disorder and parental smoking, the association between cigarette smoking and panic attack was no longer statistically significant (OR = 2.0 [.9, 4.5]), though the association between cigarette smoking and panic disorder remained (OR = 3.7 [1.6, 8.9]). The association between smoking and panic was not evident between smoking and other anxiety disorders. Conclusions These findings replicate previous results showing cigarette smoking in adolescence is associated with an increased risk of panic attacks and panic disorder in early adulthood and provide initial evidence that parental anxiety and parental smoking may play a role.
Creation of "amyloid" fibrils from Bence Jones proteins in vitro.

"Amyloid" fibrils have been created from some human Bence Jones proteins by proteolytic digestion under physiologic conditions. These fibrils with an antiparallel, β-pleated sheet conformation consist of only a portion of the variable region of the immunoglobulin light polypeptide chain and share the physical properties of amyloid fibrils. The relation between amyloidosis and immunoglobulins is thus more firmly established and a pathogenetic mechanism for amyloid fibril formation is suggested.
On the functional equations in undiscounted and sensitive discounted stochastic games

This paper considers two-person zero-sum sequential games with finite state and action spaces. We consider the pair of functional equations (f.e.) that arises in the undiscounted infinite stage model, and show that a certain class of successive approximation schemes is guaranteed to converge to a solution pair whenever an equilibrium policy with respect to the average return per unit time criterion (AEP) exists. Existence of the latter thus implies the existence of a solution to this pair of f.e. whereas the converse implication is shown only to hold under special circumstances.
Signal subspace registration of 3D images

This paper addresses the problem of fusing the information content of two uncalibrated sensors. This problem arises in registering images of a scene when it is viewed via two different sensory systems, or detecting change in a scene when it is viewed at two different time points by a sensory system (or via two different sensory systems or observation channels). We are concerned with sensory systems which have not only a relative shift, scaling and rotational calibration error, but also an unknown point spread function (that is time-varying for a single sensor, or different for two sensors). By modeling one image in terms of an unknown linear combination of the other image, its powers and their spatially-transformed (shift, rotation and scaling) versions, a signal subspace processing is developed for fusing uncalibrated sensors. Numerical results with realistic 3D magnetic resonance images of a patient with multiple sclerosis, which are acquired at two different time points, are provided.
Sorption of Mercuric Ion by Synthetic Nanocrystalline Mackinawite (FeS)

Iron sulfides are known to be efficient scavengers of heavy metals. In this study, Hg(II) sorption was investigated using synthetic nanocrystalline mackinawite (a disordered phase) as a function of initial Hg(II) concentration [Hg(II)]0, initial FeS concentration [FeS]0, total chloride concentration CIT, and pH. Hg(II) sorption mechanisms are dependent on relative concentrations of [Hg(II)]0 and [FeS]0 (the molar ratio of [Hg(II)0/[FeS]0). When the molar ratio of [Hg(II)]0/[FeS]o is as low as 0.05, adsorption is mainly responsible for Hg(II) removal, with its contribution to the overall sorption increasing at lower Cl(T). As the molar ratio increases, the adsorption capacity becomes saturated, resulting in precipitation of a sparingly soluble HgS(s). XRD analysis indicates formation of metacinnabar (beta-HgS). Concurrently with HgS(s) precipitation, the released Fe(II) from FeS(s) is resorbed by adsorption at acidic pH and either adsorption or precipitation as Fe (hydr)-oxides at neutral to basic pH. Subsequently, the Fe precipitate formed at neutral to basic pH serves as an adsorbent for Hg(II). Under the conditions where either adsorption or HgS(s) precipitation is dominant, more than 99% of [Hg(II)]0 is immobilized. When the molar ratio of [Hg(II)]0/[FeS]0 exceeds 1, the sulfide concentration is no longer sufficient for HgS(s) precipitation, and formation of chloride salts (Hg2Cl2 at acidic pH and HgCl2 x 3HgO at basic pH) occurs.
Juvenile rheumatoid arthritis, human leukocyte antigen, and other immunoglobulin supergene family polymorphisms

The following four points are discussed in this study: (1) Human leukocyte antigen (HLA) genes are associated with all groups of juvenile rheumatoid arthritis patients to varying degrees. (2) These HLA associations are similar to those of some adult inflammatory arthropathies (rheumatoid arthritis and ankylosing spondylitis), but distinct in others. (3) Predisposition commonly involves a contribution from both of a subject's HLA haplotypes. (4) Unusual immunogenetic aspects include a HLA-DP association, independent of linkage disequilibrium with other class II genes, and a HLA-associated mechanism increasing the relative proportion of girls in the involved sibships.
Modulation of cloned neuronal calcium channels through membrane-delimited pathway.

Abstract Modulation of voltage-gated Ca 2+ channels by the receptor coupled GTP-binding proteins (G-proteins) is essential for controlling secretion and muscle contraction. We have expressed cloned Ca 2+ channels in dysgenic myotubes to study G-protein modulation through the membrane-delimited pathway. The results obtained by the expression of α 1B channels and mutant channels of α 1B suggest that the two effects observed in G-protein modulated N-type channels (depression of current and slowing of activation) are through two independent mechanisms. In addition, neither the region linking repeat II and III nor carboxy-terminal region, which were demonstrated in L-type channels to determine some of their specific functions, are directly involved in G-protein modulation. The results obtained by the expression of the α 1A channel suggest that this channel is modulated through a novel membrane-delimited pathway that may not involve G-protein activation.
Pro: Early Extubation in the Operating Room Following Cardiac Surgery in Adults

There is growing evidence that the general current approach in many centers of continued mechanical ventilation following cardiac surgery has evolved through historical experience rather than having a strong physiological basis in current practice. There is evidence going back several decades supporting very early (in the operating room [OR]) extubation in pediatric cardiac anesthesia. The authors provide evidence from numerous sources showing that extubation in the OR or shortly after arrival in the ICU is safe and cost-effective and is not prevented by the type of cardiac surgery or the use of cardiopulmonary bypass. They query if the paradigm should not be reversed and very early extubation be the routine unless contraindicated. Like any anesthetic technique, appropriate patient selection is called for, but this technique is widely appropriate.
The evolution of reparative techniques for the mitral valve.

Abstract Forty-eight adult patients underwent mitral valve repair for nonischemic valvular incompetence between 1963 and 1981. Early in our experience, 21 individuals received wedge leaflet resection or leaflet plication with posteromedial commissural annuloplasty. More recently, midleaflet annuloplasty has been employed in 13 patients and is now our preferred technique. Operative mortality was 6.3%, and all deaths occurred prior to 1973. Eventually valve replacement was necessary in 10 patients; all replacements were done prior to 1977. Technical errors and progression of rheumatic disease each accounted for half of these replacements. Five-year survival by the life table method was 74 ± 9% for the entire group. Survival at 5 years for patients with prolapsing leaflets was significantly better (87 ± 7%) than for those with normal leaflet motion (46 ± 14%). A residual postoperative murmur of mitral insufficiency correlated with the likelihood of subsequent valve replacement. Important technical aspects of valve repair are described, and criteria for optimal patient selection are discussed. The evolution of reparative methods has led to a better understanding and broader application of mitral valve reconstruction.
Cholecystokinin-8 induces intracellular calcium signaling in cultured myenteric neurons from neonatal guinea pigs.

Abstract The responsiveness of cultured myenteric neurons to cholecystokinin (CCK-8) was examined using fura-2-based digital microfluorimetric measurement of intracellular calcium ([Ca2+]i). CCK-8 (10−10–10−6 M) evoked concentration-dependent increases in percentage of neurons responding (8–52%) and Δ[Ca2+]i (76–169 nM). Gastrin (1 μM) also induced an increase in [Ca2+]i in 29±6% of neurons (Δ[Ca2+]i: 71±3 nM). L-364,718, an antagonist for the CCK-A receptor, blocked [Ca2+]i response to CCK-8. Removal of extracellular calcium eliminated CCK-induced [Ca2+]i increments, as did the addition of the calcium channel inhibitors nickel (1 mM) and lanthanum (5 mM). Nifedipine (1–50 μM) dose-dependently attenuated CCK-caused [Ca2+]i responses. CCK evokes [Ca2+]i signaling in myenteric neurons by the influx of extracellular calcium, likely through L-type calcium channels.
DNA dynamics in aqueous solution: opening the double helix

The opening of a DNA base pair is a simple reaction that is a prerequisite for replication, transcription, and other vital biological functions. Understanding the mo lecular mechanisms of biological reactions is crucial for predicting and, ultimately, controlling them. Realistic computer simulations of the reactions can provide the needed understanding. To model even the simplest re action in aqueous solution requires hundreds of hours of supercomputing time. We have used molecular dy namics techniques to simulate fraying of the ends of a six base pair double strand of DNA, [TCGCGA]2, where the four bases of DNA are denoted by T thymine, C cytosine, G guanine, and A adenine, and to estimate the free energy barrier to this process. The calculations, in which the DNA was surrounded by 2,594 water mol ecules, required 50 hours of CRAY-2 CPU time for every simulated 100 picoseconds. A free energy barrier to fraying, which is mainly characterized by the movement of adenine away from thymine into aqueous environ ment, was estimated to be 4 kcal/mol. Another fraying pathway, which leads to stacking between terminal adenine and thymine, was also observed. These detailed pictures of the motions and energetics of DNA base pair opening in water are a first step toward understanding how DNA will interact with any molecule.
A skull stripping method using deformable surface and tissue classification

ABSTRACT Many neuroimagingapplications require an initial step of skull stripping to extract the cerebrum, cerebellum, andbrain stem. We approach this problem by combining deformable surface models and a fuzzy tissue classicationtechnique. Our assumption is that contrast exists between brain tissue (gray matter and white matter) andcerebrospinal uid, which separates the brain from the extra-cranial tissue. We rst analyze the intensity of theentire image to nd an approximate centroid of the brain and initialize an ellipsoidal surface around it. We thenperform a fuzzy tissue classication with bias eld correct ion within the surface. Tissue classication and biaseld are extrapolated to the entire image. The surface iteratively deforms under a force eld computed fromthe tissue classication and the surface smoothness. Because of the bias eld correction and tissue classication,the proposed algorithm depends less on particular imaging contrast and is robust to inhomogeneous intensityoften observed in magnetic resonance images. We tested the algorithm on all T1 weighted images in the OASISdatabase, which includes skull stripping results using Brain Extraction Tool; the Dice scores have an average of0.948 with a standard deviation of 0.017, indicating a high degree of agreement. The algorithm takes on average2 minutes to run on a typical PC and produces a brain mask and membership functions for gray matter, whitematter, and cerebrospinal uid. We also tested the algorithm on T2 images to demonstrate its generality, wherethe same algorithm without parameter adjustment gives satisfactory results.Keywords: Magnetic Resonance Imaging, Deformable Surface Model, Tissue Classication, Skull Stripping
Interaction between intention and environmental constraints on the fractal dynamics of human performance

The current study investigated whether the influence of available task constraints on power-law scaling might be moderated by a participant’s task intention. Participants performed a simple rhythmic movement task with the intention of controlling either movement period or amplitude, either with or without an experimental stimulus designed to constrain period. In the absence of the stimulus, differences in intention did not produce any changes in power-law scaling. When the stimulus was present, however, a shift toward more random fluctuations occurred in the corresponding task dimension, regardless of participants’ intentions. More importantly, participants’ intentions interacted with available task constraints to produce an even greater shift toward random variation when the task dimension constrained by the stimulus was also the dimension the participant intended to control. Together, the results suggest that intentions serve to more tightly constrain behavior to existing environmental constraints, evidenced by changes in the fractal scaling of task performance.
After the Organizing Ends: Workers, Self-Efficacy, Activism, and Union Frameworks

Because union organizing is commonly studied as a single event rather than the beginning of a process, little is understood about how union organizing strategies continue to affect workers after campaigns end. In this article, I analyze interviews with workers organized by two union campaign strategies, the “comprehensive campaign” and the “blitz,” which differ significantly in the degree of participation they foster among the rank and file. I apply Carole Pateman's (1970) participatory democracy theory and Erving Goffman's (1974) framework analysis to understand the meanings workers invoke to understand the campaigns and their relations to the unions. By looking at three stages within these two union organizing processes, I examine the ways that worker activism diffuses after the campaigns and across organizations.
Is What's Good for the Patient Good for the Hospital? Aligning Incentives and the Business Case for Nursing:

This article examines the social and business case for quality related to nursing and the need to restructure incentives to align the interests of the hospital and payers with the interests of the patients. Increasing the proportion of nurses who are registered nurses is associated with net cost savings. Increasing both nursing hours and the proportion of nurses who are registered nurses would result in improved quality and fewer deaths (creating a social case for improved staffing) but would be associated with small cost increases. Cost offsets associated with reduced turnover because of higher staffing would reduce the net cost increase but not result in savings. Under current reimbursement systems, hospitals that increase nurse staffing to improve patient outcomes will likely lose money as a result. Current proposals for pay for performance would create limited incentives for improving hospital nursing care.
A More Complete Conceptual Framework for Financing of Small and Medium Enterprises

The authors propose a more complete conceptual framework for analysis of credit availability for small and medium enterprises (SMEs). In this framework, lending technologies are the key conduit through which government policies and national financial structures affect credit availability. They emphasize a causal chain from policy to financial structures which affect the feasibility and profitability of different lending technologies. These technologies, in turn, have important effects on SME credit availability. Financial structures include the presence of different financial institution types and the conditions under which they operate. Lending technologies include several transactions technologies, plus relationship lending. The authors argue that the framework implicit in most of the literature is oversimplified, neglects key elements of the chain, and often yields misleading conclusions. A common oversimplification is the treatment of transactions technologies as a homogeneous group, unsuitable for serving informationally opaque SMEs, and a frequent misleading conclusion is that large institutions are disadvantaged in lending to opaque SMEs.
Pulmonary aspergillosis in acquired immune deficiency syndrome: Autopsy study of an emerging pulmonary complication of human immunodeficiency virus infection

Pulmonary aspergillosis has recently been described as an emerging infection in patients with acquired immune deficiency syndrome (AIDS), but the pathological changes have not been well documented. In this autopsy study, 17 cases of AIDS-related pulmonary aspergillosis were identified from the files of two institutions. With the exception of hypersensitivity reactions, the entire spectrum of pulmonary aspergillosis was represented. Thirteen patients exhibited acute invasive aspergillosis, and seven patients had evidence of subacute or chronic invasive infection, four of whom also had areas of acute invasion. One patient had necrotizing bronchial aspergillosis as well as acute invasive infection, and one individual had saprophytic colonization of a cavity caused by previous Pneumocystis carinii pneumonia (PCP) without evidence of invasive aspergillosis. The same conditions known to predispose immunocompromised individuals without human immunodeficiency virus (HIV) infection to invasive pulmonary aspergillosis were also identified in these patients with AIDS and included neutropenia, steroid therapy, and underlying lung disease. Additional pulmonary conditions were identified in all but one case and consisted mainly of infection or some form of chronic lung disease. In particular, half of the cases were associated with pulmonary fibrosis related to prior PCP. All cases occurred in or after 1990, confirming the perception of the recent emergence of aspergillosis in AIDS. As suggested by this study, one reason for this may be that patients with AIDS are now living long enough to develop one or more of the predisposing conditions for pulmonary aspergillosis.
Numerical simulation of ultrasonic wave propagation in anisotropic and attenuative solid materials

The axisymmetric elastodynamic finite element code developed is capable of predicting quantitatively accurate displacement fields for elastic wave propagation in isotropic and transversely isotropic materials. The numerical algorithm incorporates viscous damping by adding a time-dependent tensor to Hooke's law. Amplitude comparisons are made between the geometric attenuation in the far field and the corresponding finite element predictions to investigate the quality and validity of the code. Through-transmission experimental measurements made with a 1 MHz L-wave transducer attached to an aluminum sample support the code predictions. The algorithm successfully models geometric beam spreading dispersion and energy absorption due to viscous damping. This numerical model is a viable tool for the study of elastic wave propagation in nondestructive testing applications. >
Intragrain oxygen isotope zoning in titanite by SIMS: Cooling rates and fluid infiltration along the Carthage-Colton Mylonite Zone, Adirondack Mountains, NY, USA

Oxygen isotopes are an attractive target for zoning studies because of the ubiquity of oxygen- bearing minerals and the dependence of mineral 18 O/ 16 O ratios on temperature and fluid composi- tion. In this study, subtle intragrain oxygen isotope zoning in titanite is resolved at the 10-lm scale by secondary ion mass spectrometry. The patterns of d 18 O zoning differ depending on microstructural context of individual grains and reflect multiple processes, including diffusive oxy- gen exchange, partial recrystallization, grain-size reduction, and grain growth. Using the chrono- logical framework provided by structural relations, these processes can be related to specific events during the Grenville orogeny. Titanite was sampled from two outcrops within the Car- thage-Colton Mylonite Zone (CCMZ), a long-lived shear zone that ultimately accommodated exhumation of the Adirondack Highlands from beneath the Adirondack Lowlands during the Ott- awan phase (1090-1020 Ma) of the Grenville orogeny. Titanite is hosted in the Diana metasyenite complex, which preserves three sequentially developed fabrics: an early NW-dipping protomylonitic fabric (S1) is crosscut by near-vertical ultramylonitic shear zones (S2), which are locally reoriented by a NNW-dipping mylonitic fabric (S3). Texturally early titanite (pre-S2) shows diffusion-domi- nated d 18 O zoning that records cooling from peak Ottawan, granulite-facies conditions. Numerical diffusion models in the program Fast Grain Boundary yield good fits to observed d 18 O profiles for cooling rates of 50 � 20 ° CM a � 1 , which are considerably faster than the 1-5 ° CM a � 1 cooling rates previously inferred for the Adirondack Highlands from regional thermochronology. High cool- ing rates are consistent with an episode of rapid shearing and exhumation along the CCMZ during gravitational collapse of the Ottawan orogen at c. 1050 Ma. Texturally later titanite (syn-S2 )h as higher overall d 18 O and shows a transition from diffusion-dominated to recrystallization-dominated d 18 O zoning, indicating infiltration of elevated-d 18 O fluids along S2 shear zones and continued shear- ing below the blocking temperature for oxygen (~≤500 °C for grain sizes at the study site). The tex- turally latest titanite (post-S3 )h as growth-dominatedd 18 O zoning, consistent with porphyroblastic grain growth following cessation of shearing along the Harrisville segment of the CCMZ.
Physical unclonable functions for device authentication and secret key generation

Physical Unclonable Functions (PUFs) are innovative circuit primitives that extract secrets from physical characteristics of integrated circuits (ICs). We present PUF designs that exploit inherent delay characteristics of wires and transistors that differ from chip to chip, and describe how PUFs can enable low-cost authentication of individual ICs and generate volatile secret keys for cryptographic operations.
AMP-Activated Protein Kinase Induces a p53-Dependent Metabolic Checkpoint

Summary Replicative cell division is an energetically demanding process that can be executed only if cells have sufficient metabolic resources to support a doubling of cell mass. Here we show that proliferating mammalian cells have a cell-cycle checkpoint that responds to glucose availability. The glucose-dependent checkpoint occurs at the G 1 /S boundary and is regulated by AMP-activated protein kinase (AMPK). This cell-cycle arrest occurs despite continued amino acid availability and active mTOR. AMPK activation induces phosphorylation of p53 on serine 15, and this phosphorylation is required to initiate AMPK-dependent cell-cycle arrest. AMPK-induced p53 activation promotes cellular survival in response to glucose deprivation, and cells that have undergone a p53-dependent metabolic arrest can rapidly reenter the cell cycle upon glucose restoration. However, persistent activation of AMPK leads to accelerated p53-dependent cellular senescence. Thus, AMPK is a cell-intrinsic regulator of the cell cycle that coordinates cellular proliferation with carbon source availability.
The physical way of standardizing magnets

A new standardization method, using decreasing current cycles around the desired magnetic field B/sub */, is discussed which seems to have many advantages over the old scheme using one of the outer branches of the hysteresis loop. Experimental measurements have demonstrated the quick and good reproducibility and enhanced stability of the new method. The next step would apply some of these advantages to critical SLC (or other accelerator) magnets. >
Triaxial Woven Fabrics Part I: Behavior Under Tensile, Shear, and Burst Deformation

This paper describes some of the unique properties and performance characteristics of triaxial woven fabrics. With three systems of yarn interlacing at sixty-degree angles with one another, triaxial woven fabrics provide less of an anistotropic behavior and offer an alternative to the inherent structural weaknesses of biaxial woven fabrics: It is shown that triaxial woven fabrics exhibit a relatively higher and more uniform resistance to extension, shear deformation, and burst deformation than comparable biaxial woven fabrics.
A Functional Unit and Register Binding Algorithm for Interconnect Reduction

This paper describes a simultaneous register and functional unit (FU) binding algorithm in high level synthesis. Our algorithm targets the reduction of multiplexer inputs, shortening the total length of global interconnects. Specifically, our algorithm maximizes the interconnect sharing among FUs and registers by considering flow dependences, common primary inputs, and common register inputs among operations. Experimental results have shown that our scheme achieves more than 20% multiplexer input count reduction, on average, over previously proposed algorithms. Our approach delivers a 18% wirelength reduction of global interconnects with minor area overhead.
A new 3-D integral code for computation of accelerator magnets

A new integral code employing edge elements rather than nodal elements has overcome the difficulties associated with earlier integral codes. By using field integrals (potential differences) as solution variables, the number of unknowns is reduced to one less than the number of nodes. Two examples, a hollow iron sphere and the dipole magnet of the Advanced Photon Source injector synchrotron, show the capability of the code. The CPU time requirements are comparable to those of three-dimensional finite-element codes. Experiments show that in practice it can realize much of the potential CPU time savings that parallel processing makes possible. >
CpG oligodeoxyribonucleotides protect mice from Burkholderia pseudomallei but not Francisella tularensis Schu S4 aerosols

Studies have shown that CpG oligodeoxyribonucleotides (ODN) protect mice from various bacterial pathogens, including Burkholderia pseudomallei and Francisella tularensis live vaccine strain (LVS), when administered before parenteral challenge. Given the potential to develop CpG ODN as a pre-treatment for multiple bacterial biological warfare agents, we examined survival, histopathology, and cytokine data from CpG ODN-treated C57BL/6 mice to determine whether previously-reported protection extended to aerosolized B. pseudomallei 1026b and highly virulent F. tularensis Schu S4 infections. We found that, although CpG ODN protected mice from aerosolized B. pseudomallei challenges, the immunostimulant failed to benefit the animals exposed to F. tularensis Schu S4 aerosols. Our results, which contrast with earlier F. tularensis LVS studies, highlight potential differences in Francisella species pathogenesis and underscore the need to evaluate immunotherapies against human pathogenic species.