cssi/SciSciGPT-SciSciNet huggingface dataset:
Contributions of neuropsychology and neuroimaging to understanding clinical subtypes of mild cognitive impairment.

Publisher Summary Mild cognitive impairment (MCI) is a clinical construct that describes individuals with mildly impaired performance on objective neuropsychological tests but relatively intact global cognition and daily functioning. The chapter discusses that MCI has been validated as qualitatively different from both normal aging and dementia and is a risk factor for the development of dementia. Because of its potential importance for early identification and intervention in those at risk for the development of dementia, the concept of MCI has received considerable research attention. Conceptualizations of MCI have emerged that encompass cognitive domains other than memory. These characterizations delineate clinical subtypes that commonly include amnestic and non-amnestic forms, and that involve single and multiple cognitive domains against the backdrop of intact daily functioning. The chapter provides an overview of neuropsychological, neuroimaging, functional, and treatment findings specific to clinical subtypes of MCI. It also discusses the methodological issues involved in studying this heterogeneous population and future directions to continue to improve one's understanding of MCI and its clinical subtypes.
Drain Depth and Subirrigation in Layered Soils

The Richards equation for two-dimensional saturated—unsaturated water movement was solved for subirrigation from buried drains in layered soils. Numerical solutions were obtained for soils that have subsurface layers with high hydraulic conductivities. Results showed that increasing the drain depth so that it approaches or penetrates a high conductivity bottom layer will reduce head loss due to convergence near the drain. Deeper drains significantly increased subirrigation rates for deep soils and narrow drain spacings but had a smaller effect for shallow profiles and wide spacings. The response to deeper drains also increased with hydraulic conductivity and thickness of the bottom layer. The results showed that the drain should be placed at the interface of the high conductivity layer when possible. Further increases in the depth of the drain did not result in significant increases in subirrigation rate or water table rise.
Glutathione in the developing mouse liver--I. Developmental curve and depletion after acetaminophen treatment.

Abstract The developmental aspects of glutathione in the mouse fetal liver and the relative roles of glutathione in maternal liver, placenta and fetal liver int he protection against possible harmful effects of acetaminophen were studied. The glutatione concentration in the fetal mouse liver is significantly less than that in adult liver and reaches the adult levels about 10 days after birth. The rate of depletion of glutathione after acetaminophen administration reaches the adult levels about 15 days after birth. Treatment with 3-methylcholanthrene (MC) enhances the rate of glutathione depletion in both maternal and fetal livers of the genetically responsive C57BL/6N mouse, but not in the gentically nonresponsive AKR/N mouse. No teratogenic effects of acetaminophen were observed at doses between 100 and 250 mg kg−1 given between days 6 and 13 of gestation.
NK cell activation by the heat shock protein gp96 (VAC12P.1018)

Heat Shock Proteins (HSPs) are key mediators in the development of immune responses. Following immunization with HSPs chaperoning tumor antigens, anti-tumor immune responses are elicited. The current model of HSP mediated anti-tumor immunity suggests HSPs bind to and are internalized by antigen presenting cells (APCs), which results in the priming of effector T cells that subsequently inhibit tumor growth. In addition to APCs and T cells, NK cells have also been demonstrated to be essential for HSP mediated anti-tumor immunity. However what role NK cells play in eliciting immunity is poorly understood. In these studies, we aim to characterize the activation of NK cells following stimulation with the prototypical HSP, gp96. Our results show that, following incubation with gp96 in vitro, we observe an increase in the frequency of NK cells containing the intracellular effector proteins granzyme B and IFNγ. Although intracellular levels of IFNγ are increased, we do not detect IFNγ secretion and the intracellular levels are less than what is observed following cytokine mediated activation. Due to these responses, we are currently investigating NK cells for the presence of the HSP receptor CD91. Collectively, these data indicate that directly, HSP stimulation results in partial NK cell activation, and other mechanisms, such as indirect activation via HSP activated APCs, may be necessary to observe optimal NK cell effector functions.
Fluorometric Techniques for the Detection of Nitric Oxide and Metabolites

Recently fluorometric techniques have been developed to determine NO and S-nitrosothiols with improved sensitivity over spectrophotometric techniques based on similar chemistry. This unit contains protocols for detection and quantification of NO from chemical reactions and from cellular systems, and of S-nitrosothiols in chemical, biochemical, and cellular experiments.
A method for developing and maintaining a powerful but inexpensive computer data base of clinical information about emergency department patients

We describe a method of creating and maintaining a computer data base containing demographic, diagnostic, procedural, and laboratory data on all emergency department patients. The data base is inexpensive because it avoids redundant data entry; instead, it relies on data already entered into the hospital computers. It is unobtrusive because the ED providers do not have to complete any extra paperwork; data captured on other hospital computers are transferred to the ED data base, making the ED computer a data "parasite." It is powerful because data can be extracted in arbitrarily complex ways using common relational data base software. The data base facilitates administrative, quality improvement, and research tasks for ED managers and researchers. By using standard diagnostic and procedural coding schemes, comparison of patient populations from different EDs can be accomplished. The technologic and financial requirements of this type of data base are within the reach of most EDs.
Learning modes and subsequent use of computer-mediated communication systems

New users of four computer-mediated communication systems were asked to indicate which of a variety of learning modes they had used, including reading written manuals, using online automated help facilities, personal or group lessons from a human teacher, and trial-and-error learning. Despite often elaborate documentation and online help, the most frequent mode actually selected by users is trial and error learning. Rather than bemoaning the fact that users do not make proper use of written documentation, the implication for system implementation is that it should be designed to effectively encourage and support trial-and-error learning. An experimental intervention offering a guided learning activity supports this conclusion.
On the Set of Attainability of Nonlinear Nonautonomous Control Systems

An important tool in optimal control theory is the Pontryagin maximum principle. A necessary condition for optimality, the principle is an analytic description of a control whose response stays in the boundary of the attainable set. See [2], [23]. It is useful to know that the attainable set has a nonempty interior because the maximum principle gives no information otherwise.If we consider nonlinear, nonautonomous control systems determined by the set $\mathcal{A}^k $ of time dependent $C^k $ controllable vector fields on the m -dimensional manifold M in the Whitney $C^k $ topology and if $k \geqq 2m + 2$, then a few technical restrictions on the control system assure us that there is an open dense subset $\mathcal{O}$ of $\mathcal{A}^k $ such that for each $F \in \mathcal{O}$ the attainable set is contained in the closure of its own interior.
Pragmatic problems with step-wise refinement program development

This paper presents a generalization of two fundamental programming concepts, LOCAL ABSTRACTIONS and GLOBAL ABSTRACTIONS, and a survey of several mechanisms for implementing them. Global abstractions are semantic definitions (of objects) used throughout a program, whereas Local abstractions are refinement steps generated by the subdivision of a problem into subproblems. Global abstractions are very well supported in today's programming languages, but there is no mechanism entirely satisfactory for the "natural" development of programs using top-down step-wise decomposition techniques. Current languages lack means of expressing the hierarchical tree structure of programs. The structure of the program must be retained explicitly, and with varying degrees of detail at different levels corresponding to the way the program was developed. There is an important deficiency in the process of refining the solution to a problem: local abstractions, which describe intermediate stages of the solution, are replaced by their corresponding refinements.In particular, we discuss some inadequacies of "the facto" structuring constructs in modern languages, showing that, for instance, procedures should not be used for represeting refinements, since these are intended to control the "static" program structure (refinements may well represent non-executable pieces of code!). Finally, we propose the introduction of two new DESIGN constructs for developing structured programs which can show and maintain the solutions's structure as produced during the development process.
The initial growth of Ag films on W(110): a helium diffraction study

Abstract Growth of Ag films on W(110) has been monitored for substrate temperatures between 170 and 800 K. In agreement with earlier studies we find that two epitaxial layers are formed which are stable up to the desorption temperature. We have determined the buckling amplitude of these incommensurate structures and find that they are less than expected from a hard-sphere model using a uniformly distorted (111) plane for the Ag film. We conclude that local rearrangements must take place in the film. In comparison with Cu growth, we find that the monolayer is less well ordered although the defect density is no more than 8% at 1.0 ML. No stable layer by layer growth occurs for coverages above the bilayer. Layer by layer growth does not occur at 170 K where diffusion is too slow to allow the necessary material transport.
Are Remittances an Effective Mechanism for Development? Evidence from Tajikistan, 1999–2007

In many remittance-receiving countries, evidence linking remittances to household economic stability and investment is limited. Using three cross-sectional national surveys (1999, 2003, 2007) we co...
Do Policies Aimed Toward the Homeless Help Families? The Detroit Experience

Agencies providing services for families experiencing homelessness face challenges, particularly with diminishing resources driven and prioritized by policy mandates. To understand the impact of policies related to homeless families, we conducted a qualitative, exploratory study including the chief executive officers (CEOs) and/or executive directors (EDs) of five family homeless providers in southeast Michigan. Our analysis revealed that policies for homeless families are made with limited input from service providers and recipients. Providers struggle to deliver services within narrow funding boundaries and worry about future needs of homeless families. Future policies must increase stakeholder input to maximize policy relevance and effectiveness.
Discourse, Foucault, and Critical Medical Anthropology

One of the major research interests of critical medical anthropology is the examination of Western biomedicine. The concepts of discourse and genealogy elaborated in the writing of Michel Foucault are particularly useful in this task. In addition, the notion of discursive structure defines a unit of investigation well suited to the anthropological examination of complex society. This paper reviews some of these theoretical and methodological possibilities, and then looks at the case example of borderline hypertension in 20th-century American culture drawn from the author's dissertation research.
The biological race concept as a research tool.

In present day research in human biology, the validity of the concept of biological race rests on its utility as a research tool. The methodology of this research into human biological variability is a multidimensional application of the comparative method, utilizing, as one dimension, genetic distance. The body of this paper suggests two generalizing principles for the establishment of genetic distance. Genetic distance may occur due to physical or temporal isolation or in conjunction with environmental differences. A brief analysis of the fifteenth century human populations examines the relationship between these principles and presently used racial taxonomic systems. It is concluded that race may be defined operationally as a rough measure of genetic distance in human populations and as such may function as an informational construct in the multidisciplinary area of research in human biology.
Intracellular Ca2+ Stores and Ca2+ Influx Are Both Required for BDNF to Rapidly Increase Quantal Vesicular Transmitter Release

Brain-derived neurotrophic factor (BDNF) is well known as a survival factor during brain development as well as a regulator of adult synaptic plasticity. One potential mechanism to initiate BDNF actions is through its modulation of quantal presynaptic transmitter release. In response to local BDNF application to CA1 pyramidal neurons, the frequency of miniature excitatory postsynaptic currents (mEPSC) increased significantly within 30 seconds; mEPSC amplitude and kinetics were unchanged. This effect was mediated via TrkB receptor activation and required both full intracellular Ca2+ stores as well as extracellular Ca2+. Consistent with a role of Ca2+-permeable plasma membrane channels of the TRPC family, the inhibitor SKF96365 prevented the BDNF-induced increase in mEPSC frequency. Furthermore, labeling presynaptic terminals with amphipathic styryl dyes and then monitoring their post-BDNF destaining in slice cultures by multiphoton excitation microscopy revealed that the increase in frequency of mEPSCs reflects vesicular fusion events. Indeed, BDNF application to CA3-CA1 synapses in TTX rapidly enhanced FM1-43 or FM2-10 destaining with a time course that paralleled the phase of increased mEPSC frequency. We conclude that BDNF increases mEPSC frequency by boosting vesicular fusion through a presynaptic, Ca2+-dependent mechanism involving TrkB receptors, Ca2+ stores, and TRPC channels.
PAR proteins and the cytoskeleton: a marriage of equals

The PAR proteins are a group of widely conserved regulators of polarity, many of which are asymmetrically localized in polarized cells. Recent work shows that distinct modes of actomyosin- and microtubule-based transport contribute to the establishment of PAR asymmetries in different cell types. Cross-regulatory interactions among PAR proteins and with other conserved polarity complexes stabilize asymmetries once they form, and shape the evolution of PAR protein distributions in response to cytoskeletal transport or other polarizing inputs. The PAR proteins in turn modulate the actomyosin and microtubule cytoskeletons. In some cases, this is a form of feedback control, central to the establishment and maintenance of PAR asymmetries. In others, it underlies the elaboration of functional cell polarity.
Direct measurements of the rate coefficient for the reaction OH+CH4 → CH3+H2O over 300-1500 K

The flash photolysis/resonance fluorescence technique for styding OH radical kinetics was extended to temperatures above 1500 K using the High Temperature Photochemistry reactor. In this application to combustion related processes, direct measurements of the rate coefficient for the benchmark reaction, OH+CH4 → CH3+H2O were obtained over the widest temperature range to date on this reaction and are described by the expression: k(T)=10−16.59±0.68 T1.83±0.17 exp [−1396±134/T] cm3 molecule−1 s−1 (298-1512K) This expression ties together previous low and high temperature data, and allows use of the rate coefficient over the measurement temperatures to an estimated accuracy of 10% or better. It also provides a firmer basis for the extrapolation of k(T) to higher temperatures, and allows critical comparison with theoretical calculations. The experimental methods employed are applicable, with minor modifications, to the study of many OH reactions over the temperature range 300-1500 K. An upper limit of ≈ 1600 K was found on the use of H2O as a photolytic source of OH radicals for kinetic studies, due to the thermal dissociation of H2O at higher temperatures.
Relationships between measures of auditory verbal learning and executive functioning

Abstract Relationships between performance on the California Verbal Learning Test (CVLT) and executive abilities were examined. In a sample of 115 neurological cases principal components factor analysis produced five theoretically and clinically meaningful CVLT factors. The five CVLT factors reflected general verbal learning (CVLT1), response discrimination (CVLT2), a proactive interference effect or “working memory” (CVLT3), serial learning strategy (CVLT4), and a retroactive interference effect (CVLT5). Canonical correlation between executive function measures and the five CVLT factor scores yielded one significant canonical variable accounting for 29 percent of the variance in the data. Two CVLT factors (CVLT1 and CVLT3), the Trail Making Test Part B, and Digit Span were significantly correlated with the canonical variate. Higher levels of memory performance were associated with better attention and mental tracking. Based on the present findings, attentional aspects of executive abilities appear to pla...
The other side of molecular biology

Abstract The question is raised whether in addition to the well-known causal processes of molecular mechanics there are other effects of atomic physics which might appear significantly in biology. We find one, namely the process of molecular synthesis that involves ambiguities due to the competition of isomers. The ambiguities, mathematically called bifurcations, represent binary decisions buried in noise. The assumption is made that collectively there are enough causally undefined decisions to speak of the creativity of the organism as a basic phenomenon in its own right. Creativity, in the past a purely literary term, becomes then a scientific one for which exact definitions are required. We point out that in such a case theory can only specify necessary conditions of phenomena not sufficient ones, as distinct from physics. A very brief survey is made of the major features of a biological theory based on such assumptions.
Composition of Raw and Roasted Lamb and Mutton II. Amino Acids

SUMMARY Microbiological assay values are reported for content of 18 amino acids in separable lean of raw and roasted rib-loin and leg cuts of lamb and mutton. These values agreed well with values obtained in other laboratories. The amino acid content of lamb protein tended to be constant and was not affected by cut or by roasting. Retentions of amino acids in lamb lean after roasting were essentially complete.
Effects of pH and phosphate on metal distribution with emphasis on As speciation and mobilization in soils from a lead smelting site

Arsenic in soils from the Asarco lead smelter in East Helena, Montana was characterized by X-ray absorption spectroscopy (XAS). Arsenic oxidation state and geochemical speciation were analyzed as a function of depth (two sampling sites) and surface distribution. These results were compared with intensive desorption/dissolution experiments performed in a pH stat reactor for samples from the site with the highest degree of As heterogeneity. The objectives of the study were to investigate the solid-phase geochemical As speciation, assess the speciation of As in solutions equilibrated with the solids under controlled pH (pH=4 or 6) and Eh (using hydrogen or air) environments, observe the effects of phosphate on the release of As into solution, and examine the effects of phosphate on metal mobility in the systems. Arsenic was predominantly found in the As(V) valence state, though there was evidence that As(III) and As(0) were present also. The dominant geochemical phase was scorodite (FeAsO4·2H2O). The pH was controlled in the pH stat experiments by the addition of equinormal solutions of monoprotic (HNO3), diprotic (H2SO4), or triprotic (H3PO4) acids. For many of the divalent metal cations, solution concentrations greatly decreased in the presence of phosphate. Solutions were also analyzed for anions. Evidence exists for sulfate release into solution. More As was released into solution at lower pH. A slight increase in solution arsenate occurs with the addition of phosphate, but the risk posed from the increased desorption/dissolution of As must be weighed against the decrease in solution concentrations of many metals especially Pb. If tailings from this site underwent acidification (e.g., acid mine drainage), in situ sequestration of metals by phosphate could be combined with placement of subsurface permeable reactive barriers for capture of As to reduce the risk associated with arsenic and trace metal mobilization. Results from this study could be used in risk management plans for sites similar to the Pb smelter site examined here.
Tetraphyllins A and B, deidaclin and epitetraphyllin B from Tetrapathaea tetrandra (Passifloraceae)

Abstract Tetraphyllin A, deidaclin, tetraphyllin B and epitetraphyllin B have been isolated from the vegetative parts of Tetrapathaea tetrandra (Passifloraceae), a liana which is native to New Zealand. The fruits of this plant have previously been shown to contain tetraphyllins A and B. This is the first report of the isolation of four cyclopentenoid cyanogenic compounds from a single plant.
Contextual and Competitive Interference: Inhibition or Facilitation?

Existing literature has found two sources of advertising interference, competitive and contextual, that decrease the effectiveness of an ad in a cluttered environment. However, to date, the negative impact of competitive and contextual interference has been examined independently. This research explores advertising effectiveness when these sources exist concurrently. Contrary to the supposition concerning the additive effects of both sources of interference when simultaneously present, our findings indicate that viewing ads for the same product category with similar executional elements leads to the dissipation of interference effects (Study 1). Consistent with the process rationale, when a product-brand cue (versus a picture cue) is provided, this novel effect disappears (Study 2). The implications of these findings for advertising are highlighted in the discussion section.
Solutions of the nonlinear Boltzmann equation describing relaxation to equilibrium

A moment method is used to obtain exact solutions of the nonlinear Boltzmann equation for the relaxation to equilibrium of a spatially uniform gas of Maxwell-model molecules. The results contradict a recent conjecture of Krook and Wu concerning similarity solutions. Unless the initial conditions are very special, long-time relaxation follows linear modes corresponding to solutions of the linearized Boltzmann equation, rather than similarity solutions. Application of the moment method to other collision models gives approximate rather than exact results, but shows that there is coupling between the linear relaxation modes, which are independent for the Maxwell model. At long times all moments, therefore, decay together along the lowest linear mode. Numerical calculations for rigid spheres illustrate this behavior.
Listeria monocytogenes keratitis.

We treated a farmer who had Listeria monocytogenes bacterial keratitis. Therapy with topical antibiotics was unsuccessful; it was necessary to treat the patient with topical and systemic penicillin and gentamicin. To elucidate the pathogenesis of this infection, we developed a rabbit model. Using the patient's strain of L. monocytogenes , we determined that the severity of the rabbit infection was dose-related. If we used an inoculum of more than 10 7 organisms, many of the features of the human Listeria keratitis were mimicked. We also found that treatment with either penicillin or gentamicin did not control the infection as well as using both antibiotics simultaneously, a combination which resulted in relatively rapid resolution of infection and no corneal scarring. The human and animal data indicate that L. monocytogenes can be a virulent corneal pathogen. Listeria corneal infections must be treated aggressively with both penicillin and gentamicin to prevent permanent visual loss.
Discrete chromatic series

Chromatic series are series expansions in which the coefficients are linear combinations of derivatives of a function. They were introduced by Ignjatovic (Introduction to Signal Processing Based on Differential Operators, Tech. Rep. 1, Kromos Technology, available at http://www.kromos.com, February 2001.) as a replacement for Taylor's series and are based on orthogonal polynomials. However, real data usually involves the values of a function and not its derivatives which are needed in both theories. In this article, we replace the derivatives by discrete values in the calculations of the coefficients.
Isolator-combustor interaction in a dual-mode scramjet engine

A constant-area diffuser, or 'isolator', is required in both the ramjet and scramjet operating regimes of a dual-mode engine configuration in order to prevent unstarts due to pressure feedback from the combustor. Because the nature of the combustor-isolator interaction is different in the two operational modes, however, attention is presently given to the use of thermal vs kinetic energy coordinates for these interaction processes' visualization. The results of the analysis thus conducted indicate that the isolator requires severe flow separation at combustor entry, and that its entropy-generating characteristics are more severe than an equivalent oblique shock. A constant-area diffuser is only marginally able to contain the equivalent normal shock required for subsonic combustor entry.
Calibration of a planar differential CO2 probe

The working mechanism of the differential CO2 sensor inherently contains several calibration problems. These difficulties are highlighted and some possibilities for eliminating them are discussed. Finally, a simple error analysis is shown for optimizing the composition of the standard solutions to be used for the calibration of the differential CO2 probe in blood electrolyte analyzers.
THE CIRCADIAN RHYTHM OF BIOLUMINESCENCE IN PYROCYSTIS IS NOT DUE TO DIFFERENCES IN THE AMOUNT OF LUCIFERASE: A COMPARATIVE STUDY OF THREE BIOLUMINESCENT MARINE DINOFLAGELLATES

The biochemistry and circadian regulation of luminescence in two Pyrocystis species, P. lunula Hulburt and P. noctiluca Murray et Haeckel, were compared with a well-studied species, Gonyaulax polyedra Stein. All exhibit circadian rhythms and all have similar luciferins and luciferases. However, the Pyrocystis species lack a second protein involved in the reaction in Gonyaulax, the luciferin (substrate) binding protein, which sequesters the luciferin at the cytoplasmic pH and releases it upon acidification, thus controlling the characteristic flashing, which is similar in the three species. More striking is the difference in the circadian regulation of luminescence, which in Gonyaulax involves the daily synthesis and destruction of the two proteins, along with the luminous organelles (scintillons) from which light is emitted, and which are present in all species. In the Pyrocystis species, the amount of luciferase is the same in extracts made during the day and night phases; its circadian regulation in vivo may be attributed to a change in its localization from day to night phase.
Evidence for improved conclusion accuracy after reading about rather than conducting a belief‐inconsistent simple physics experiment

Prior beliefs that contradict data may interfere with the ability to draw accurate conclusions; however, evidence shows that through engaged activity individuals may learn new information. In Experiment 1, undergraduates performed or read about two physics experiments involving a ball and ramp. The first experiment was consistent with most people's prior beliefs, while the second was inconsistent with most people's prior beliefs. Participants' predictions, experimentation adequacy, conclusions and ability to generalize knowledge were measured to determine the effects of prior belief bias depending on whether participants conducted or read about the experiment. In Experiment 2, a structured hands-on condition was included and developmental trends across adolescence and adulthood were examined. In both Experiments, reading about a belief-inconsistent experiment led to improved conclusion accuracy and ability to generalize knowledge as compared to performing the experiment. This was the case when experiments were performed well and after a 12-week delay for adolescents. Copyright © 2009 John Wiley & Sons, Ltd.
Triosidines: novel Maillard reaction products and cross-links from the reaction of triose sugars with lysine and arginine residues

The role of the highly reactive triose sugars glyceraldehyde and glyceraldehyde-3-phosphate in protein cross-linking and other amino acid modifications during the Maillard reaction was investigated. From the incubation of glyceraldehyde with N (alpha)-acetyl-L-lysine and N (alpha)-acetyl-L-arginine, we isolated four new Maillard reaction pyridinium compounds named 'triosidines'. Two of them, 'lys-hydroxy-triosidine' [1-(5-amino-5-carboxypentyl)-3-[(5-amino-5-carboxypentylamino)methyl]-5-hydroxypyridinium] and 'arg-hydroxy-triosidine' [2-(4-amino-4-carboxybutylamino)-8-(5-amino-5-carboxypentyl)-6-hydroxy-3,4-dihydro-pyrido[2,3-d]pyrimidin-8-ium] are fluorescent, UV-active Lys-Lys and Lys-Arg cross-links respectively. Their structures were identified by NMR and MS. In addition, two UV-active lysine adducts, 'trihydroxy-triosidine' [1-(5-amino-5-carboxypentyl)-3,4-dihydroxy-5-(hydroxymethyl)pyridinium] and 'triosidine carbaldehyde' [1-(5-amino-5-carboxypentyl)-3-formylpyridinium] were tentatively identified by MS. All structures involve six sugar-derived carbons as part of the heterocyclic ring. Of the two novel cross-links, only arg-hydroxy-triosidine was formed by glyceraldehyde-3-phosphate, an intermediate metabolite of the glycolytic pathway. Lys-hydroxy-triosidine and arg-hydroxy-triosidine were detected in human and porcine corneas treated with glyceraldehyde. The HPLC-fluorescence identification was confirmed by MS. Triosidines were also formed from dihydroxyacetone, a widely used artificial sun-tanning agent. Triosidines are expected to be useful tools in tissue engineering, where the utilization of highly reactive sugars is needed to stabilize the loose matrix. In addition, they are expected to be present in selected biological conditions, such as on consumption of a high fructose diet, and syndromes associated with high glyceraldehyde excretion, such as Fanconi Syndrome, fructose-1,6-diphosphatase deficiency and tyrosinaemia.
Evolution of the mitochondrial DNA control region in the mbuna (Cichlidae) species flock of lake Malawi, East Africa

Considerable controversy has surrounded the application of mitochondrial DNA data to reconstruction of evolutionary relationships among the endemic cichlids of Lake Malawi. Central to this debate has been the issue of whether lineage sorting is complete, and thus whether these data actually reflect species phylogeny, or simply gene genealogy. Review of all mtDNA control region sequences available for members of one monophyletic subset of this species flock, the Malawi rockfishes, or mbuna, strongly indicates that lineage sorting is incomplete: Character-based analyses of these sequences reconstruct gene, not species, interrelationships. Analysis of the pattern of nucleotide substitutions differentiating these mtDNA alleles suggests that pyrimidine residues undergo transition substitutions more often than do purines. Estimation of the magnitude of derived sequence differentiation in light of the reconstructed gene genealogy suggests that the mbuna may be of considerably more recent vintage than previous molecular characterizations have indicated.
Solar cycle evolution of the heliospheric magnetic field: The Ulysses legacy

Abstract Important contributions of Ulysses to understanding the solar cycle evolution of the heliospheric magnetic field (HMF) and solar wind are reviewed: a dramatic reorientation of the HMF as the solar dipole rotates between axial and equatorial orientations; solar cycle variation of the total heliospheric magnetic flux and its response to changes in solar magnetic fields; the unusual on-going solar minimum and its effects; a connection between magnetic flux and solar wind mass flux in the heliosphere and at the source; a recurrent north–south heliospheric asymmetry at solar minimum and the equatorial offset of the solar magnetic dipole.
Compositional specification and realisation of mixed-initiative web dialogs

We present DialogXML – a markup language approach to specifying and realising mixed-initiative web dialogs on mobile devices. By capturing the functional structure of the dialog independent of the modalities used to realise it, DialogXML facilitates the implementation of web interfaces that integrate hyperlink and speech modes of interaction. It enables the creation of websites that adapt to the needs of users yet permits the designer fine-grained control over what interactions to support. The framework uses an algorithm based on staging transformations – an approach that represents dialogs by programs and uses program transformations to simplify them based on user input. Design methodology, implementation details, and two case studies are presented.
High quality methylome-wide investigations through next-generation sequencing of DNA from a single archived dry blood spot

The potential importance of DNA methylation in the etiology of complex diseases has led to interest in the development of methylome-wide association studies (MWAS) aimed at interrogating all methylation sites in the human genome. When using blood as biomaterial for a MWAS the DNA is typically extracted directly from fresh or frozen whole blood that was collected via venous puncture. However, DNA extracted from dry blood spots may also be an alternative starting material. In the present study, we apply a methyl-CpG binding domain (MBD) protein enrichment-based technique in combination with next generation sequencing (MBD-seq) to assess the methylation status of the ~27 million CpGs in the human autosomal reference genome. We investigate eight methylomes using DNA from blood spots. This data are compared with 1,500 methylomes previously assayed with the same MBD-seq approach using DNA from whole blood. When investigating the sequence quality and the enrichment profile across biological features, we find that DNA extracted from blood spots gives comparable results with DNA extracted from whole blood. Only if the amount of starting material is ≤ 0.5µg DNA we observe a slight decrease in the assay performance. In conclusion, we show that high quality methylome-wide investigations using MBD-seq can be conducted in DNA extracted from archived dry blood spots without sacrificing quality and without bias in enrichment profile as long as the amount of starting material is sufficient. In general, the amount of DNA extracted from a single blood spot is sufficient for methylome-wide investigations with the MBD-seq approach.
Enhancing the performance of a dynamically partitionable bus network using a graph coloring algorithm

An efficient dynamic graph traversal algorithm is used to identify non-conflicting requests and to allocate network resources in a dynamically partitionable bus network (DPBN). A special processor receives from the control computer of a partitionable bus network an adjacency matrix which indicates conflicts among requests. It applies the dynamic graph traversal algorithm and returns the identified non-conflicting requests to the control computer. The control computer then physically partitions the network into a number of subnetworks for processing non-conflicting requests in parallel. The results of performance evaluation show a forty percent decrease of network delay as compared with a fully utilized, but unpartitioned local area network.
Inhibitory effect of toluene on tumor promotion in mouse skin.

In the two-stage mouse model for skin tumorigenesis with phorbol-12-myristate-13-acetate (PMA) as promoter, topical application of 40 microliters of toluene 2X/week at the initiation/promotion site (the back) reduced the average number of tumors/mouse (ANT/M) to approximately one-fourth that of controls. Control procedure involved initiation of C3H mice with benzo[a]pyrene (BaP) and CD-1 mice with 7,12-dimethylbenz[a]anthracene (DMBA) followed by promotion with from 1 to 5 micrograms PMA in 40 microliters acetone 2X/week. Forty microliters of toluene 2X/week per se was a weak promoter (6-13% of control ANT/M), and produced mild skin irritation at the application site but behavior and body weights were normal. The toluene inhibition of tumorigenesis was not a direct chemical action on PMA since similar effects occurred whether toluene was the vehicle for PMA or whether it was applied up to 1 day before PMA (i.e., prepromotion). Prepromotion with acetone had no effect on tumorigenesis, substantiating its use as control vehicle and suggesting that the toluene inhibition was a specific tissue reaction. The inhibitory effect appeared to be on PMA promotion rather than on initiation since toluene and acetone produced similar numbers of tumors when used as the vehicle for BaP or DMBA in two-stage or BaP in single-stage trials. The inhibition was not permanent since tumorigenesis returned to control rates 2-3 weeks after prepromotion with toluene ceased but promotion with PMA in acetone continued. Toluene may be unique among reported promotion inhibitors in that it is a widely used commercial chemical which sometimes serves as a vehicle in cancer-screening trials. Since its metabolism is reasonably well defined, it may be of value in exploring further the process of tumor promotion.
Trade and Integration in the Caribbean

This paper analyzes trade in the Caribbean community (CARICOM) using a gravity model framework. The paper seeks to shed light on the dynamics of trade among CARICOM member countries, as well with the rest of world over 1980-99. Overall, the results show that intra-CARICOM trade has increased, suggesting that further regional integration is desirable. At the same time, CARICOM's trade with the rest of the world has risen as well, fueled notably by the reduction of the arrangement`s common external tariff and despite the negative impact of the declining preferential access to EU markets for banana. In contrast, WTO membership does not appear to have had a positive impact on trade. Overall, it appears that trade liberalization is consistent with greater CARICOM trade integration.
Reliability of Tanner staging performed by orthopedic sports medicine surgeons.

AB Purpose: The treatment of anterior cruciate ligament (ACL) tears in children is controversial because of the potential injury to the growth plate resulting from traditional transphyseal surgery. Some authors recommend Tanner staging as a method to determine the patient's maturity to decide between physeal-sparing or transphyseal surgery. This study examines the accuracy and interobserver and intraobserver reliabilities of Tanner staging performed by orthopedic surgeons. Methods: Twenty-eight photographs representing Tanner stages 1-5 were obtained from a pediatric endocrinologist. Four sports medicine orthopedic surgeons received a tutorial on Tanner staging and independently graded the photographs twice, with a 1-month interval between grading exams. The endocrinologist's grade was considered correct. Intraobserver and interobserver reliabilities were determined. Results: The overall average correct scores were as follows: 53% correct Tanner stages on exam 1 and 59% correct on exam 2. The average results for specific Tanner stages were as follows: Tanner stage 1 = 62% correct on exam 1, 83% on exam 2; Tanner stage 2 = 60%/65%; Tanner stage 3 = 60%/46%; Tanner stage 4 = 45%/55%; and Tanner stage 5 = 50%/45%. Per examiner, correct grading was as follows: examiner 1 = 39% on exam 1 and 35% on exam 2; examiner 2 = 67%/82%; examiner 3 = 50%/42%; and examiner 4 = 67%/75%. When comparing the grading between exams 1 and 2, examiner 1 changed five answers from correct to incorrect; four answers from incorrect to correct; and two answers from incorrect to a different incorrect choice; examiner 2, three/seven/zero; examiner 3, six/four/one; and examiner 4, two/four/zero. Conclusions: Preoperative Tanner staging performed by orthopedic surgeons is unreliable with large intraobserver and interobserver variabilities. Therefore, relying on Tanner staging as a method to guide decision making for surgery in skeletally immature patients with ACL tears may lead to inadvertent growth plate injury.
Discussion of “Forces exerted by waves on a sloping board”

Although the author of this paper makes it clear that a sloping board of moderate proportions can only be an effective breakwater for waves of very short length, the writer has been approached by persons who conceive such a breakwater to be of universal application. The purpose of this discussion is therefore to elaborate on the author's remarks as to the effectiveness of a sloping board as a breakwater, and in particular to point out the importance of the ratio of wave length to water depth in analyzing the behavior of a surface obstacle such as a sloping board.
Inter-annual higher germination from smaller than medium-sized premontane wet forest fragments for an animal-dispersed tree species in Costa Rica

Forest fragmentation is pervasive in tropical landscapes, and animal-dispersed tree species are among the most threatened. Seed source is an important factor for active conservation and restoration efforts for such species but many studies show lower germination levels for seeds collected from small fragments compared to larger forests. However, the increasing rarity of large forests makes them difficult to be used as practical seed sources. We assessed the potential of small to medium-sized fragments (19–209 ha) to serve as seed sources for the conservation and restoration of an animal-dispersed tree Lacistema aggregatum (Lacistemataceae) in Costa Rican premontane wet forests. Germination, seedling survivorship, and growth for 2 years were quantified in a screen house environment. Two years later, more rigorous germination tests were conducted. Germination levels differed substantially among source trees. Seeds from some individuals had no germination inter-annually, suggesting that fecundity alone may be an incomplete indicator of individual fitness. Furthermore, in contrast to many previous studies, germination was better for seeds from smaller fragments for both study years. Subsequent seedling survivorship did not counteract the trends generated by germination, and the better performance of seeds from smaller fragments was retained for 2 years as ex situ seedlings. Higher seed quality in smaller fragments was associated with larger seed size in trees near forest edges, which might result from higher potential outcrossing rates. Our results suggest a previously unrecognized potential of small fragments as seed sources.
A pharmacokinetic comparison of cephalexin and cefadroxil using HPLC assay procedures

The pharmacokinetics of cephalexin and cefadroxil were compared following single 500 mg oral doses to 12 healthy male volunteers. Doses were administered after an overnight fast according to a crossover design. Plasma and urinary levels of both compounds were determined by HPLC procedures. Cephalexin was absorbed rapidly, achieving a mean peak plasma level of 17.5 micrograms ml-1 at 1 h, compared to 16 micrograms ml-1 at 1.8 h for cefadroxil. Elimination half-lives of cephalexin and cefadroxil were 0.7 and 1.1 h, respectively. The area under the cefadroxil plasma curve was significantly larger than that for cephalexin. However, after allowing for differences in elimination rate constants and assuming equal distribution volumes, plasma data indicated the compounds were equally well absorbed. Only 70 per cent of cefadroxil was recovered in urine compared to 87 per cent of cephalexin during the 12 h following drug administration. The therapeutic significance of the different pharmacokinetic characteristics of cephalexin and cefadroxil, if any, may be a function also of their pharmacologic activity and/or the sensitivity of the target organism.
Resistance against spider mites in cotton induced by mechanical abrasion

Mechanical abrasion of cotyledons induced resistance to spider mites (Tetranychus urticae Koch) in cotton plants in four of six replicates. Mite population growth was reduced on plants that had either been abraded or had been previously exposed to mite feeding, compared to undamaged controls. Populations of mites were not different for plants that were abraded and for those that had been exposed previously to mites. In two of the six replicates, mite populations were not different for abraded, previously exposed and control plants. In these two replicates, densities of mites were greater than in the four replicates in which abrasion and previous exposure were effective, although the reasons for this discrepancy are not known. Induction of resistance by mechanical abrasion indicates that the response is not caused only by some factor specific to mites but can be caused by general wounding. RESUME Induction par abrasion mecanique de la resistance aux acariens sur coton L'abrasion mecanique des cotyledons a induit la resistance aux acariens (Tetranychus urticae) sur des pieds de coton dans 4 repetitions sur 6. La croissance des populations d'acariens sur plantes abrasees ou precedemment exposees a l'alimentation des acariens, etait plus faible que celle des temoins. Les populations d'acariens sur plantes abrasees et sur plantes exposees precedemment aux acariens ne differaient pas. Dans 2 des 6 lots, les populations d'acariens ne differaient pas sur plantes abrasees, precedemment exposees ou temoin. Dans ces 2 lots, les densites d'acariens etaient plus elevees que dans les 4 autres, ou l'abrasion et l'exposition anterieure etaient efficaces, bien ce que les raisons de cette discordance soient inconnues. L'induction de la resistance par une abrasion mecanique montre que la reaction n'est pas provoquee seulement par quelque facteur specifique pour les acariens, mais par une reponse generale aux blessures.
The use of distortion product otoacoustic emissions in the estimation of hearing and sensory cell loss in noise-damaged cochleas

Distortion product otoacoustic emissions (DPOAE), permanent threshold shifts (PTS) and outer hair cell (OHC) losses were analyzed in a population of 187 noise-exposed chinchillas to determine the predictive accuracy (sensitivity and specificity) of the DPOAE for PTS and OHC loss. Auditory evoked potentials (AEP) recorded from the inferior colliculus of the brainstem were used to estimate hearing thresholds and surface preparation histology was used to determine sensory cell loss. The overlapping cumulative distributions and high variability in emission responses for both PTS and OHC loss made it difficult to predict AEP threshold and OHC loss from DPOAE level measurements alone. Using a strict criterion (i.e. emissions better than the 5th percentile of the preexposure DPOAE level, and PTS 30 dB or OHC loss>40%). However, the high variability of individual DPOAE responses resulted in a broad region of 'uncertainty' (i.e. 5 or = 50%) or PTS (> or = 35 dB) in noise-exposed chinchillas. Based on an exponential regression analysis of individual subjects, correlations were higher for PTS/DPOAE than for OHC loss/DPOAE.