cssi/SciSciGPT-SciSciNet huggingface dataset:
Capillarity-Mediated Grain Growth in 3-D

Space-filling in kinetically active 3-d network structures, such as polycrystalline solids at high temperatures, is treated using topological methods. The theory developed represents individual network elements—the polyhedral cells or grains—as a set of objects called average N-hedra, where N, the topological class, equals the number of contacting neighbors in the network. Average N-hedra satisfy network topological averages for the dihedral angles and quadrajunction vertex angles, and, most importantly, act as “proxies” for real irregular polyhedral grains with equivalent topology. The analysis provided in this paper describes the energetics and kinetics of grains represented as average N-hedra as a function of their topological class. The new approach provides a quantitative basis for constructing more accurate models of three-dimensional grain growth. As shown, the availability of rigorous mathematical relations for the curvatures, areas, volumes, free energies, and rates of volume change provides precise predictions to test simulations of the behavior 3-d networks, and to guide quantitative experiments on microstructure evolution in three-dimensional polycrystals.
Molecular Analysis of Dehalococcoides 16S Ribosomal DNA from Chloroethene-Contaminated Sites throughout North America and Europe

The environmental distribution of Dehalococcoides group organisms and their association with chloroethene-contaminated sites were examined. Samples from 24 chloroethene-dechlorinating sites scattered throughout North America and Europe were tested for the presence of members of the Dehalococcoides group by using a PCR assay developed to detect Dehalococcoides 16S rRNA gene (rDNA) sequences. Sequences identified by sequence analysis as sequences of members of the Dehalococcoides group were detected at 21 sites. Full dechlorination of chloroethenes to ethene occurred at these sites. Dehalococcoides sequences were not detected in samples from three sites at which partial dechlorination of chloroethenes occurred, where dechlorination appeared to stop at 1,2-cis-dichloroethene. Phylogenetic analysis of the 16S rDNA amplicons confirmed that Dehalococcoides sequences formed a unique 16S rDNA group. These 16S rDNA sequences were divided into three subgroups based on specific base substitution patterns in variable regions 2 and 6 of the Dehalococcoides 16S rDNA sequence. Analyses also demonstrated that specific base substitution patterns were signature patterns. The specific base substitutions distinguished the three sequence subgroups phylogenetically. These results demonstrated that members of the Dehalococcoides group are widely distributed in nature and can be found in a variety of geological formations and in different climatic zones. Furthermore, the association of these organisms with full dechlorination of chloroethenes suggests that they are promising candidates for engineered bioremediation and may be important contributors to natural attenuation of chloroethenes.
Extensive polymorphism of the BOLA-DRB3 gene distinguished by PCR-RFLP

A polymerase chain reaction (PCR)-based method is described for typing of alleles of the bovine lymphocyte antigen (BoLA)-DRB3 gene. A total of 30 DRB3 alleles were distinguished by digestion of PCR amplification products of BoLA-DRB3 exon 2 with RsaI, BstYI and HaeIII (PCR-RFLP). All restriction fragment patterns, with the exception of one HaeIII pattern, were consistent with restriction sites that were found among 14 previously sequenced DRB3 alleles. The PCR-RFLP typing method was evaluated on 168 genomic DNA samples collected from animals of 10 cattle breeds, 48 of which were typed in the Fourth International BoLA Workshop for BoLA-DRB and -DQ by conventional restriction fragment length polymorphism (RFLP) analysis using heterologous and homologous DNA probes. Thirty-one DRB/DQ haplotypes containing 23 DRB3 alleles were identified among the 48 workshop animals analysed. Using PCR-RFLP, 11 DRB3 alleles were identified in 18 workshop animals for which DRB RFLPs were not informative. PCR-RFLP typing of additional animals revealed five new DRB3 alleles, of which three contained a putatively located three basepair deletion in the identical position as found for the sequenced allele DRB*2A. PCR-RFLP was shown to be a rapid and sensitive method for the detection of polymorphism in a functionally relevant domain of the BoLA-DRB3 gene and should be useful for studying the evolution of DRB polymorphism in cattle and other Bovidae.
Model system takes us a step closer to efficacious imaging biomarkers of angiogenesis in head and neck cancer

Commentary to:Establishment and characterization of patient tumor-derived head and neck squamous cell carcinoma xenograftsMukund Seshadri, Mihai Merzianu, Haikuo Tang, Nestor R. Rigual, Maureen Sullivan-Nasca, Thom R. Loree, Saurin R. Popat, Elizabeth A. Repasky and Bonnie L. Hylander
Simultaneous measurements of radii and wall thickness of microvessels in the anesthetized rat.

The purpose of this investigation was to measure the radius and wall thickness of small blood vessels in mesentery and striated (cremaster) muscle in the anesthestized rat. Using the method of image-splitting, the vessel images were sheared at magnifications of 3,OOOx and 6,500x on the video screen. In the resting state, the mean lumen values for the thinnest portion of endothelial capillary were 4.1 ± 1.2µ (SD) in cremaster and 5.6 ± 1.3µ (SD) in mesentery. Lumen and total diameter were also greater at several levels of precapillary arterioles in mesentery than similar vessels in cremaster, suggesting that smaller vessel size in cremaster might be characteristic of this tissue. Vasoconstriction of up to 50% from resting state is associated with an increase in wall thickness and a decrease in lumen to wall ratio due to a disproportional decrease in radius (inner greater than outer radius). Similarly, an increase in vessel radius in a proportion 4 to 1 (inner greater than outer) was sustained up to about 6...
Investigating the dependence of polymorphic liquid-liquid transitions on the concentration of amphiphiles in water

A way of identifying polymorphic transitions via the hydrolysis of S-decylisothiuronium chloride and other properties of water in solutions of amphiphiles is described. Features of amphiphile transitions (smoothness, micelle bistability, solubilization hysteresis, the autooscillation of micelles, and fluctuations in the extensive properties of a water and micelle nanosystem ensemble) are discussed.
Factored, a-stable, linear multistep methods: an alternative to the method of lines for multidimensions

Historically, the development and analysis of methods for ordinary differential equations (ODEs) have been more advanced than those for partial differential equations (PDEs). The present state of numerical methods is no exception; therefore, it behooves the numerical analyst to exploit sophisticated ODE methods for the numerical solution of PDEs.
When the world turned

The Genesis of the Copernican World. By Hans Blumenberg. Translated by Robert M. Wallace. MIT Press: 1987. Pp. 772. $40, £35.95.
The Impact of a Pharmacist's Participation on Hospitalists' Rounds:

Background: Expanding the role of pharmacists in the hospital setting has the potential to positively impact the quality of patient care and provide cost savings. Previous studies have shown that integrating pharmacists into rounding teams can enhance patient care through interventions at the point of assessment and prescribing. This study examines these potential benefits at a community hospital that does not have formal hospitalist rounds and in which the pharmacists must make recommendations via written communication.Objective: The primary objective was to identify the number of interventions and to determine how to optimally utilize a pharmacist for a group of 19 hospitalists. Secondary objectives included estimating pharmacist time invested and cost savings.Methods: Initially, methods in this study included reviewing patient medication profiles and informally rounding with the hospitalists. Interventions were performed at the time of rounding. After 2 weeks of rounding, methods were altered to improv...
Targeted Eradication of Ovarian Cancer Mediated by Intracellular Expression of Anti-erbB-2 Single-Chain Antibody

Abstract Objective: Overexpression of the tyrosine kinase receptor erbB-2 is important in the pathogenesis of a variety of neoplasms including ovarian cancer. As a strategy to selectively eradicate erbB-2-overexpressing tumor cells, an anti-erbB-2 single-chain immunoglobin (sFv) gene was constructed to direct expression of intracellular anti-erbB-2 antibody. The purpose of this study is to establish tim antitumorigenicity of this strategy in in vitro and in vivo models. Methods: An anti-erbB-2 sFv construct containing an endoplasmic reticulum (ER)-directed leader sequence was transiently expressed in the human ovarian carcinoma cell line SKOV3 using the adenovirus-polylysine vector. SKOV3 cells transfected with a non-ER form of an anti-erbB-2 sFv construct or an irrelevant plasmid DNA served as controls. Antitumorigenicity, as measured by anchorage-independent growth in soft agar and subcutaneous (sc) tumor formation, was analyzed. The ability to achieve a biological effect with relevant sFv in murine orthotopic xenograft models and in primary human ovarian cancer cells was also evaluated. Results: The ER form of anti-erbB-2 sFv was found to exert a marked antineoplastic effect on the SKOV3 cell line resulting in an arrest of anchorage-independent growth. A significant increase in sc tumor volume was noted in animals challenged with control constructs. In marked contrast, complete tumor eradication was noted at necropsy 80 days after sc transplantation in the group challenged with the ER-directed anti-erbB-2 sFv gene. Intraperitoneal treatment of malignant ascites in human tumor xenograft models with the ER form of the anti-erbB-2 sFv gene resulted in profound downregulation of cell surface erbB-2 in retrieved ovarian cancer cells. The ER-directed anti-erbB-2 sFv also elicited a significant cytotoxic effect in transfected primary ovarian cancer cells obtained from a patient with malignant ascites. Conclusion: The ability to selectively "knock out" erbB-2 demonstrates that this strategy can induce a significant antineoplastic effect in ovarian cancer cells overexpressing this growth factor receptor. In addition, the ability to accomplish selective abrogation of erbB-2 expression in animal treatment models and to transfect and eradicate primary ovarian cancer cells justifies further investigation of this novel strategy in ovarian cancer patients.
A theoretical study of membrane constraint in polymer-electrolyte fuel cells

A mathematical model is developed that examines the effect of having a constrained membrane in a fuel cell. During operation, a polymer-electrolyte fuel-cell membrane is prone to swell but is unable to do so by system design. This builds up a stress that affects transport in, and the properties of, the membrane. This report is the first to incorporate such effects into a macrohomogeneous model. Both the physical and mathematical effects are described. Results include the magnitude of constraint, the change in water content of the membrane attributed to constraint, and one-dimensional simulations showing the effect of constraint on the water balance of the fuel cell. The paper demonstrates the need for considering membrane constraint both in modeling and experimental studies of fuel cells. © 2004 American Institute of Chemical Engineers AIChE J, 50: 3215–3226, 2004
SURFACE CHEMISTRY OF THE HYDRANDEPTS AND ITS RELATION TO NITRATE ADSORPTION AS AFFECTED BY PROFILE DEPTH AND DEHYDRATION1

Summary The pH0 and ZPC of two Hydiandepts were determined by potentiomettic titiation in NaCl and by ion adsorption measurements from NH4NO3, respectively. The decrease of pH, pH0, and ZPC due to drying was explained by the hydrolysis reaction. Partial drying, high organic matter content, and low Al2 O3 concentration in the surface soil were responsible for its low pH, pH0 and ZPC. The high pH0 of subsoils was attributed to the presence of amorphous aluminosilicates and mixed polymeric gels of Fe(III) and A1 with high water content. The significant decrease of nitrate adsorption due to dehydration is discussed in relation to the change in pH, pH0, ZPC, and surface area on drying.
Effects of stimulus comparison during discrimination training on subsequent transposition and generalization gradients

Only pigeons in a comparison group were afforded opportunity for direct comparison between stimuli on the same dimension. Following discrimination learning both a comparison and a noncomparison group were given post discrimination generalization tests and transposition tests. The results provided further evidence for a correspondence between postdiscrimination and transposition data. However, this correspondence was not complete, as Ss without peak shifts produced statistically significant transposition scores. Also the comparison group produced a significantly greater amount of transposition. Differences in transposition scores between the comparison and noncomparison groups, however, were not reflected in underlying differences in the postdiscrimination generalization gradients.
The origin of deoxynucleosides in brain : Implications for the study of neurogenesis and stem cell therapy

Detection of DNA synthesis in brain employing ((3)H)thymidine (((3)H)dT) or bromo deoxyuridine (BrdU) is widely used as a measure of the "birth" of cells in brain development, adult neurogenesis and neuronal stem cell replacement strategies. However, recent studies have raised serious questions about whether this methodology adequately measures the "birth" of cells in brain either quantitatively or in an interpretable way in comparative studies, or in stem cell investigations. To place these questions in perspective, we review deoxynucleoside synthesis and pharmacokinetics focusing on the barriers interfacing the blood-brain (cerebral capillaries) and blood-cerebrospinal fluid (choroid plexus), and the mechanisms, molecular biology and location of the deoxynucleoside transport systems in the central nervous system. Brain interstitial fluid and CSF nucleoside homeostasis depend upon the activity of concentrative nucleoside transporters (CNT) on the 'central side' of the barrier cells and equilibrative nucleoside transporters (ENT) on their 'plasma side.' With this information about nucleoside transporters, blood/CSF concentrations and metabolic pathways, we discuss the assumptions and weaknesses of using ((3)H)dT or BrdU methodologies alone for studying DNA synthesis in brain in the context of neurogenesis and potential stem cell therapy. We conclude that the use of ((3)H)dT and/or BrdU methodologies can be useful if their limitations are recognized and they are used in conjunction with independent methods.
Intracellular distribution of type II collagen mRNA and prolyl 4-hydroxylase in embryonic avian corneal epithelia.

Background The distribution of endoplasmic reticulum (ER) proteins and type II collagen mRNA in whole mount preparations of embryonic corneal epithelia was investigated. We asked, do transmission electron microscopy (TEM) and confocal microscopy of chick prolyl 4-hydroxylase (CPH) show similar ER distributions as CPH is necessary for collagen biosynthesis? Methods The overall distribution of ER was analyzed by TEM. Collagen secreting ER was localized with antibodies to chick prolyl 4-hydroxylase (CPH, CPH-α, or CPH-β subunits). Type II collagen mRNA distribution was determined by in situ hybridization. Results The ER localized with TEM, and immunohistochemistry using anti-CPH antibodies, showed similar distribution patterns. Immunostaining for CPH and CPH-β was prominent in both periderm and basal cells and also appeared to stain the periderm apical surface. CPH-α was less intense, only localizing to ER regions. The basal cell CPH distribution appeared perinuclear in optical sections that contained nuclei, but occupied nearly all the cytoplasm in a reticular pattern above and below nuclei, similar to that seen with TEM cross-sections. Epithelia double labeled with propidium iodide and CPH showed overlapping cytoplasmic staining. The distribution of type II collagen mRNA was similar to the ER staining pattern, appearing to represent a subset of total ER. Conclusions This study demonstrates that ER markers have a similar distribution as type II collagen mRNA in embryonic avian corneal epithelia. In addition the CPH subunits had distinct, but overlapping distributions, suggesting that they may act independently. © 1996 Wiley-Liss, Inc.
Making educational games that work in the classroom: A new approach for integrating STEM simulations

The development of analytical skills is a central goal of the Next Generation Science Standards and foundational to subject mastery in STEM fields. Yet, significant barriers exist to students gaining such skills. Here we describe a new “gentle-slope” cyberlearning strategy that gradually introduces students to the authoring of scientific simulations via a Web-based modding approach called CyberMOD. Modding involves adding agents with predefined functionality to a simulation world to produce a unique combination whose behavior can then be visualized by running the simulation. This permits low barrier experimentation on the modded simulation, which is hoped to help students gain a deeper understanding of scientific phenomena that is the focus of the activity. Our research questions are: i) does this approach encourage students' interest in computational science and ii) does it enhance their analytical abilities, and iii) does it foster a deeper understanding of the processes modded? Here we take an in-depth look at what was created for the CyberMOD infrastructure and analyze the results of initial in-class studies as to the effectiveness of this strategy. The results support the premise that teachers can easily integrate CyberMOD into their in-class activities, that CyberMOD activities encourage creative student learning, and that the CyberMOD approach facilitates student understanding.
Automatic Versus Contingent Mechanisms of Sensory-Driven Neural Biasing and Reflexive Attention

Recent studies have generated debate regarding whether reflexive attention mechanisms are triggered in a purely automatic stimulus-driven manner. Behavioral studies have found that a nonpredictive "cue" stimulus will speed manual responses to subsequent targets at the same location, but only if that cue is congruent with actively maintained top-down settings for target detection. When a cue is incongruent with top-down settings, response times are unaffected, and this has been taken as evidence that reflexive attention mechanisms were never engaged in those conditions. However, manual response times may mask effects on earlier stages of processing. Here, we used event-related potentials to investigate the interaction of bottom-up sensory-driven mechanisms and top-down control settings at multiple stages of processing in the brain. Our results dissociate sensory-driven mechanisms that automatically bias early stages of visual processing from later mechanisms that are contingent on top-down control. An early enhancement of target processing in the extrastriate visual cortex (i.e., the P1 component) was triggered by the appearance of a unique bright cue, regardless of top-down settings. The enhancement of visual processing was prolonged, however, when the cue was congruent with top-down settings. Later processing in posterior temporal–parietal regions (i.e., the ipsilateral invalid negativity) was triggered automatically when the cue consisted of the abrupt appearance of a single new object. However, in cases where more than a single object appeared during the cue display, this stage of processing was contingent on top-down control. These findings provide evidence that visual information processing is biased at multiple levels in the brain, and the results distinguish automatically triggered sensory-driven mechanisms from those that are contingent on top-down control settings.
Role of the bases and phosphoryl bases of phospholipids in the autoxidation of methyl linoleate emulsions

Methyl linoleate, emulsified in borate buffer with sodium lauryl sulfate, was used to study the pro- or antioxidant effect of 0-phosphocholine, 0-phosphoethanolamine, 0-phosphoserine, as well as the corresponding nonphosphoryl compounds. Oxygen uptake was calculated from rate data obtained at 37 C with an oxygen electrode. The results were similar for the corresponding phosphoryl and nonphosphoryl bases. 0-Phosphocholine and choline had little effect at either pH 7.9 or 10.2. 0-Phosphoethanolamine and ethanolamine significantly increased oxygen uptake at pH 7.9, but significantly decreased uptake at pH 10.2. 0-Phosphoserine and serine decreased oxygen uptake at both pH values. The catalytic activities of the bases investigated may be attributed to their functional groups. The phosphoryl and β-hydroxy groups exhibited no catalytic activity in the autoxidation of methyl linoleate emulsions at either pH 7.9 or 10.2. The α-carboxyl amino group of 0-phosphoserine and serine decelerated autoxidation at both pH values. The amino group H3N+ of the primary amine accelerated autoxidation, but the H2N: group and the reverse effect. Since the quaternary amino group (CH3)3N+ did not affect autoxidation at either pH 7.9 or 10.2, we concluded that the presence of the N−H bond may be necessary for the prooxidant activity of an amine, and that the presence of a pair of free electrons on the nitrogen of an amine is necessary for its antioxidant activity. Kinetically, the autoxidation of methyl linoleate emulsion without added base was in agreement with Farmer’s proposed mechanism involving a bimolecular dissociation of hydroperoxides. However, methyl linoleate emulsion at pH 7.9 and 37 C in the presence of ethanolamine or 0-phosphoethanolamine was autoxidized by a mechanism involving a combined mono- and bimolecular dissociation of hydroperoxides.
Diverse Transcriptional Programs Associated with Environmental Stress and Hormones in the Arabidopsis Receptor-Like Kinase Gene Family

The genome of Arabidopsis thaliana encodes more than 600 receptor-like kinase (RLK) genes, by far the dominant class of receptors found in land plants. Although similar to the mammalian receptor tyrosine kinases, plant RLKs are serine/threonine kinases that represent a novel signaling innovation unique to plants and, consequently, an excellent opportunity to understand how extracellular signaling evolved and functions in plants as opposed to animals. RLKs are predicted to be major components of the signaling pathways that allow plants to respond to environmental and developmental conditions. However, breakthroughs in identifying these processes have been limited to only a handful of individual RLKs. Here, we used a Syngenta custom Arabidopsis GeneChip array to compile a detailed profile of the transcriptional activity of 604 receptor-like kinase genes after exposure to a cross-section of known signaling factors in plants, including abiotic stresses, biotic stresses, and hormones. In the 68 experiments comprising the study, we found that 582 of the 604 RLK genes displayed a two-fold or greater change in expression to at least one of 12 types of treatments, thereby providing a large body of experimental evidence for targeted functional screens of individual RLK genes. We investigated whether particular subfamilies of RLK genes are responsive to specific types of signals and found that each subfamily displayed broad ranges of expression, as opposed to being targeted towards particular signal classes. Finally, by analyzing the divergence of sequence and gene expression among the RLK subfamilies, we present evidence as to the functional basis for the expansion of the RLKs and how this expansion may have affected conservation and divergences in their function. Taken as a whole, our study represents a preliminary, working model of processes and interactions in which the members of the RLK gene family may be involved, where such information has remained elusive for so many of its members.
Towards an architectural treatment of software security: a connector-centric approach

Security is a very important concern for software architecture and software components. Previous modeling approaches provide insufficient support for an in-depth treatment of security. This paper argues for a more comprehensive treatment based on software connectors. Connectors provide a suitable vehicle to model, capture, and enforce security. Our approach models security principal, privilege, trust, and context of architectural constituents. Extending our existing architecture description language and support tools, our approach can facilitate describing the security characteristics of an architecture generating enabling infrastructure, and monitoring run-time conformance. Initial results of applying this approach are illustrated through a case study. The contribution of this research is a deeper and more comprehensive treatment of architectural security through software connectors.
Laparoscopic repair of potentially contaminated abdominal ventral hernias using a xenograft: a case series.

Background The aim of this study was to describe the preliminary experience of definitive single stage laparoscopic reconstruction of the abdominal wall utilizing a tissue matrix in a potentially contaminated surgical field.
Future of electronic printing

Since the mid-1970s, electronic printing has been available to businesses. Its growth has been truly amazing. Original predictions of a need for no more than 500 laser printers has now given way to millions of printers of all types from home and personal office to the print shop. This paper is intended to look at what the future of electronic printing might look like. Any prognostication of the future is always risky and the intent here is to look at what has happened and what is happening in the marketplace and thus get some view of the future. Will the printer vendors of today be the printer vendors tomorrow? What will be the market leading characteristics of future electronic printers? Can we measure value to the first order? We shall try to briefly explore these and some other questions in order to pursue some idea of where the business is going.
Downstaging of Breast Carcinomas in Older Women Associated with Mammographic Screening

▪ Abstract: The efficacy of mammographic screening for older women has not been well studied. The present study was designed to evaluate for downstaging of breast carcinomas associated with mammographic screening in older women. The study population consisted of 130 women age 65 years with newly diagnosed breast carcinoma in 1993–1994 and was obtained from women enrolled in a large health maintenance organization. Mammographic screening, if done, was performed by a network of predominantly community-based radiologists. Significant downstaging was found for the breast cancers detected in women who had undergone mammographic screening compared to the breast cancers detected in women who had not undergone mammographic screening. The American Joint Committee on Cancer (AJCC) clinical stage was stage 0 and stage I in 7% (8/107) and 73% (78/107), respectively, of the breast cancers detected in women who had undergone mammographic screening compared to 0% (0/23) and 22% (5/23), respectively, of the breast cancers detected in women who had not undergone mammographic screening (p < 0.0001). Clinical Tis and T1 tumors were found in 7% (8/107) and 74% (79/107), respectively, of the breast cancers detected in women who had undergone mammographic screening compared to 0% (0/23) and 22% (5/23), respectively, of the breast cancers detected in women who had not undergone mammographic screening (p < 0.0001). Of the 102 AJCC clinical stage I–II breast cancers with known pathologic axillary lymph node staging, lymph node stage was N0 for 76% (66/87) of the women who had undergone mammographic screening compared to 53% (8/15) of the women who had not undergone mammographic screening (p = 0.019). The results of downstaging reported in this study are important because earlier staged lesions are associated with an improved prognosis and an increased potential for breast-conservation treatment. These findings have shown that mammographic screening is effective in downstaging breast carcinomas found in older women. ▪
Early deaths due to hemorrhage and leukostasis in childhood acute myelogenous leukemia. Associations with hyperleukocytosis and acute monocytic leukemia

There were 294 children with acute myelogenous leukemia (AML) entered into the German AML Berlin, Frankfurt, and Munster hospitals (BFM) 78 and 83 studies. Thirty (10%) died as a result of hemorrhage and/or leukostasis prior to or in the first 12 days of therapy. The risk of early death due to hemorrhage and/or leukostasis is significantly greater when certain features are initially present: acute monocytic leukemia (French-American-British [FAB] M5), hyperleukocytosis (greater than or equal to 100,000/microliter), and extramedullary organ involvement (P less than 0.001). The risk increases sharply when these factors exist in combination: 72% mortality with FAB M5 and hyperleukocytosis, and 43% with FAB M5 and extramedullary organ involvement. In 11 patients leukostasis alone or in combination with hemorrhage was probably the cause of death during the first 3 days after diagnosis. All 11 children presented with hyperleukocytosis and were classified as monocytic subtype FAB M4 or M5. After induction, a close temporal association between rapid blast reduction and occurrence of fatal hemorrhage was established in five patients. Thrombocytopenic hemorrhages were controllable and, therefore, responsible for death only in exceptional cases. It is difficult to avoid these early fatal complications with current therapeutic measures. Early exchange transfusion together with special supportive care may be useful.
Precision of sustained fixation in trained and untrained observers

During visual fixation, microscopic eye movements shift the image on the retina over a large number of photoreceptors. Although these movements have been investigated for almost a century, the amount of retinal image motion they create remains unclear. Currently available estimates rely on assumptions about the probability distributions of eye movements that have never been tested. Furthermore, these estimates were based on data collected with only a few, highly experienced and motivated observers and may not be representative of the instability of naive and inexperienced subjects in experiments that require steady fixation. In this study, we used a high-resolution eye-tracker to estimate the probability distributions of gaze position in a relatively large group of human observers, most of whom were untrained, while they were asked to maintain fixation at the center of a uniform field in the presence/absence of a fixation marker. In all subjects, the probability distribution of gaze position deviated from normality, the underlying assumption of most previous studies. The resulting fixational dispersion of gaze was much larger than previously reported and varied greatly across individuals. Unexpectedly, the precision by which different observers maintained fixation on the marker was best predicted by the properties of ocular drift rather than those of microsaccades. Our results show that, during fixation, the eyes move by larger amounts and at higher speeds than commonly assumed and highlight the importance of ocular drift in maintaining accurate fixation.
β-carotene alters vitamin E protection against heme protein oxidation and lipid peroxidation in chicken liver slices

Abstract This study investigated the interaction between dietary β-carotene and vitamin E in protecting against heme protein oxidation and lipid peroxidation initiated by incubation of liver slices with ferrous sulfate. Male leghorn chicks were fed a basal diet deficient in β-carotene and vitamin E for 3 weeks. Beta-carotene (0, 30, and 100 mg/kg) and vitamin E (0, 50 mg/kg) were added to the diet using a 3 × 2 factorial arrangement of treatments. Analysis of variance showed the following significant effects. Vitamin E protected against both heme protein oxidation and lipid peroxidation as measured by thiobarbituric acid reactive substances ( P ≤ 0.001). Liver slices from vitamin E adequate chicks had less hemichrome and produced fewer thiobarbituric acid reactive substances than liver slices from vitamin E-deficient chicks. Addition of β-carotene to the diets did not protect chicks significantly against either hemichrome formation or the production of thiobarbituric acid reactive substances ( P ≤ 0.001). Supplementation of the vitamin E-adequate diet with 100 mg β-carotene/kg diet resulted in substantially lower retention of hepatic vitamin E ( P ≤ 0.001).
A graph-theoretic optimal control problem for terminating discrete event processes

Most of the results to date in discrete event supervisory control assume a “zero-or-infinity” structure for the cost of controlling a discrete event system, in the sense that it costs nothing to disable controllable events while uncontrollable events cannot be disabled (i.e., their disablement entails infinite cost). In several applications however, a more refined structure of the control cost becomes necessary in order to quantify the tradeoffs between candidate supervisors. In this paper, we formulate and solve a new optimal control problem for a class of discrete event systems. We assume that the system can be modeled as a finite acylic directed graph, i.e., the system process has a finite set of event trajectories and thus is “terminating.” The optimal control problem explicitly considers the cost of control in the objective function. In general terms, this problem involves a tradeoff between the cost of system evolution, which is quantified in terms of a path cost on the event trajectories generated by the system, and the cost of impacting on the external environment, which is quantified as a dynamic cost on control. We also seek a least restrictive solution. An algorithm based on dynamic programming is developed for the solution of this problem. This algorithm is based on a graph-theoretic formulation of the problem. The use of dynamic programming allows for the efficient construction of an “optimal subgraph” (i.e., optimal supervisor) of the given graph (i.e., discrete event system) with respect to the cost structure imposed. We show that this algorithm is of polynomial complexity in the number of vertices of the graph of the system.
Role of Mitogen-Activated Protein Kinases in Ischemia and Reperfusion Injury The Good and the Bad

There is growing evidence that multiple mitogen-activated protein (MAP) kinases are activated during ischemia and/or reperfusion and may contribute to the structural and functional changes after myocardial ischemia. A new study by Yue et al1 in this issue of Circulation Research attempts to address the role of MAP kinases in ischemic myocardium and suggests that ERK1/ERK2 is part of a “survival” pathway whereas p38 and JNK mediate a “death” pathway in the ischemic myocardium. Myocyte loss during the acute stage of myocardial infarction involves both apoptotic and necrotic cell death.2 3 4 Therefore, it is reasonable to think that the balance of cell survival and death is critical during the pathological evolution of postischemic cardiac dysfunction. Recently, many scientists seeking to elucidate the intricate relationship between signal transduction and this balance of survival and death in ischemic myocardium have focused on MAP kinases. MAP kinases are highly conserved serine/threonine kinases that are activated in response to a wide variety of stimuli including growth factors, G protein–coupled receptors, and environmental stresses.5 Consequently, they play a role in numerous cell functions including growth and proliferation. The MAP kinases themselves require dual phosphorylation on a Thr-X-Tyr motif to become active. Three major MAP kinase cascades have been extensively studied in the heart: extracellular signal–regulated kinases (ERK1 and ERK2), c-Jun N-terminal kinases (JNK1 and JNK2), and p38 kinases, of which the p38α and p38β isoforms are found in the heart.5 Recently, a fourth MAP …
Separation of retinoid receptors from cultured retinoblastoma cells

Abstract Receptor proteins for [3H] retinol and [3H] retinoic acid in cultured human retinoblastoma cells have been separated rapidly and reproducibly by two different methods. By isoelectric focusing, the isoelectric point of the retinol receptor is at pH 4.0; the retinoic acid receptor has a higher isoelectric point of 4.3. Polyacrylamide slab gel electrophoresis revealed a slower migration rate for the [3H] retinoic acid receptor compared to the [3H] retinol receptor. The separate nature of the two proteins has thus been established in this unique human cell line.
The Relation Between Flow Rate and Axial Pressure Gradient for Time-Periodic Poiseuille Flow in a Pipe

Consider a fully developed, time-periodic motion of a Navier–Stokes fluid in an infinite straight pipe of constant cross section Ω (time-periodic Poiseuille flow). In this note we show that the axial pressure gradient and the flow rate associated to this motion are uniquely connected through a very simple relation involving parameters depending only on Ω and, therefore, independent of the particular velocity field. One immediate and important consequence of this property is that it allows for a very elementary proof of existence of time-periodic Poiseuille flow under a given flow rate.
An automated vital sign monitoring system for congestive heart failure patients

Congestive heart failure (CHF) is a cardiovascular disorder that affects approximately 4.6 million Americans and is a leading cause of death in the United States. Current research shows that strategies to promote early recognition and treatment of symptoms and enhance self-care management behaviors reduce unnecessary hospitalizations. However, mechanisms to monitor patients' health status and behaviors are limited by constraints imposed by the patient's geography, infirmity, or resources. Remote monitoring supports a more dynamic connection between healthcare providers and patients, improves health promotion and patient care through monitoring of health data, communicates health reminders, and makes provisions for patient feedback. This paper will describe two versions of Weight and Activity with Blood Pressure Monitoring System (WANDA [22]) that leverages sensor technology and wireless communication to monitor health status of patients with CHF. The WANDA system is built on a three-tier architecture consisting of sensors, a web server, and back-end database tiers. The system was developed in conjunction with the UCLA School of Nursing and the UCLA Wireless Health Institute to enable early detection of key clinical symptoms indicative of CHF-related decompensation in a real-time automated fashion and allows health professionals to offer surveillance, advice, and continuity of care and triggers early implementation of strategies to enhance adherence behaviors. The small study has enabled patients to reduce or maintain the number of readings which are out of the acceptable range. For diastolic, systolic, and heart rate values, the t-test results show that the WANDA study is effective for patients with CHF.
Electrons in the ionopause boundary layer of Venus

Measurements made by the retarding potential analyzer on board the Pioneer Venus Orbiter (PVO) have indicated the presence of both magnetosheath electrons and atmospheric photoelectrons in the plasma mantle region of Venus, which lies just outside the ionopause. A theoretical model of the spatial and energy distribution of electrons in the plasma mantle has been constructed using the two-stream electron transport method and the time-dependent electron energy equation. Magnetic field lines parallel to the ionopause are assumed. Transport and collisional processes, including electron scattering by neutrals and ions, are taken into consideration. The calculated electron spectra in the mantle show signatures of both solar wind electrons and photoelectrons. Cold ionospheric electrons are present only for altitudes below the ionopause. The calculated electron temperatures agree very well with the PVO data both in the mantle region and in the magnetized ionosphere.
BOOTSREG: An SAS Matrix Language Program for Bootstrapping Linear Regression Models

BOOTSREG is an SAS/IML program for performing the bootstrap resampling technique in regression analysis. The program can be used in any version of SAS as long as the installation includes the Interactive Matrix Language (IML) module of the SAS system. Program input and output are both highly automated, so the users need to know very little about the SAS system or the SAS language. The program produces both standard regression results (parameter estimates, goodness of fit, and standard errors) and boot-strapped sampling distributions for the parameter estimates. The program outputs both statistical summaries and graphical representations of the bootstrap distributions for each regression coefficient.
Südländisch: the borders of fear with reference to Foucault

This article examines the term ‘sudlandisch’ in the German news media's description of two suspected terrorists, whose images were captured on video surveillance cameras as they were planting bombs on two German trains in Summer 2006. Strictly untranslatable in just one word, the term sudlandisch is commonly used to designate anyone who appears to come from a ‘southern’ or Mediterranean country, or simply anyone who appears ‘brown.’ However, as this article discusses, the video surveillance footage was of such low quality that this description was almost arbitrary. The images of the suspects were not any ‘browner’ than those of the bystanders whose images were also captured on the video surveillance footage. This article uses the occasion of this medial incident to address the problem of referentiality in Michel Foucault's notion of ‘discourse,’ showing how the term sudlandisch functions as a discursive formation. Focusing on the borders of discourse as the constitutive moment of discourse, this article t...
Critical Literacy as Comprehension: Expanding Reader Response

This article presents the theoretical underpinnings of critical literacy and related principles. It also provides ideas for creating environments to promote reading from a critical stance, teaching strategies, sample classroom applications, and annotated lists of theme-related texts. When engaging in critical literacy, readers move beyond traditional beliefs about reading comprehension to read not only the word but also the world. Raising questions about whose voices are represented in the text, whose voices are missing, and who gains and who loses by the reading of the text helps readers understand the text's purpose and avoid being manipulated by it. A number of essential understandings and beliefs about the power relationship between the reader and the author underpin critical literacy. These principles include focusing on issues of power and promoting reflection, transformation, and action; focusing on the problem and its complexity; understanding that critical literacy strategies are dynamic and adapt to the contexts in which they are used; and examining multiple perspectives.
Neurological and EEG findings in the monkey after total body x-irradiation.

Abstract Serial neurological and EEG examinations have been made in monkeys subjected to lethal and near-lethal doses of total body X-irradiation. With the onset of symptoms of radiation sickness, behavioral alterations consisting of anorexia, listlessness and hypokinesia appeared and, in severely ill animals, progressed to prostration and coma before death. Depression of iridal and tendon reflexes was encountered in such severely ill monkeys and, in one case, tic-like jerks of the neck and upper extremities were displayed terminally. In convalescent and surviving cases, no behavioral or neurological abnormalities were exhibited. Preliminary study of the normal monkey's EEG revealed low voltage fast discharge associated with alertness or excitement, an alpha rhythm of 7–9.5/sec. in relaxed wakefulness and large 1–2/sec. humps or waves with drowsiness or sleep. The induction of Nembutal anesthesia in the normal animal was associated with a period of low fast discharge before regular, high amplitude 1/sec. waves appeared. The overall EEG picture after irradiation was that of no significant change from normal. However, a slight slowing and greater irregularity of the alpha rhythm was present in several animals from the day of radiation. In pre-terminal stages, when the animal was severely ill, the EEG was greatly altered and consisted of high voltage, slow waves which gave way to an almost iso-electric tracing before death. These terminal alterations appeared secondary to general breakdown of the body's homeostasis, and the present findings are considered to be in accord with those of others which point to a high degree of resistance or protection of the nervous system to irradiation.
Lysis of gram-negative organisms and the role of versene.

Abstract Conditions for lysis of E. coli B, Azotobacter vinelandii, Ps. aeruginosa and Ps. fluorescens by lysozome have been described; the three active agents required are: lysozyme, Versene (EDTA) and Tris buffer. Lysis of these organisms was shown to vary with the pH of the lysing medium, physiological age of the culture and the type of culture medium. The function of Versene in relation to metals associated with cell walls of E. coli and A. vinelandii was discussed.
Epistemological Beliefs and Thinking About Everyday Controversial Issues

The authors investigated the relationship between individuals' beliefs about the nature of knowledge and the nature of learning (epistemological beliefs) and their thinking about everyday controversial issues. Adults (N = 174) ranging in age from 17 to 71 years old with a mean age of 38 completed the Schommer Epistemological Questionnaire (M. Schommer, 1990), which assessed their beliefs in the certainty and organization of knowledge and the speed and control of learning. After they had completed the questionnaire, they responded to a series of questions about two controversial issues that had been discussed in the local newspaper. Regression analyses indicated that the more the participants believed in complex and tentative knowledge, the more likely they were to take on multiple perspectives, be willing to modify their thinking, withhold ultimate decisions until all information was available, and acknowledge the complex, tentative nature of everyday issues. Epistemological beliefs that are heavily influenced by a higher level of education appear to relate to thinking beyond the classroom, and introducing controversial issues into the curriculum may reciprocally foster the development of epistemological beliefs.
Intraoral palatal mucosal graft harvest

Summary The anatomy of the hard palate is reviewed with respect to the clinical considerations of harvesting intraoral hard palate grafts for various reconstructive eyelid procedures. Recommendations for harvesting grafts based on these anatomic principles are given.