cssi/SciSciGPT-SciSciNet huggingface dataset:
Strain Shielding from Mechanically Activated Covalent Bond Formation during Nanoindentation of Graphene Delays the Onset of Failure

Mechanical failure of an ideal crystal is dictated either by an elastic instability or a soft-mode instability. Previous interpretations of nanoindentation experiments on suspended graphene sheets,1,2 however, indicate an anomaly: the inferred strain in the graphene sheet directly beneath the diamond indenter at the measured failure load is anomalously large compared to the fracture strains predicted by both soft-mode and acoustic analyses. Through multiscale modeling combining the results of continuum, atomistic, and quantum calculations, and analysis of experiments, we identify a strain-shielding effect initiated by mechanochemical interactions at the graphene-indenter interface as the operative mechanism responsible for this anomaly. Transmission electron micrographs and a molecular model of the diamond indenter's tip suggest that the tip surface contains facets comprising crystallographic {111} and {100} planes. Ab initio and molecular dynamics (MD) simulations confirm that a covalent bond (weld) formation between graphene and the crystallographic {111} and {100} facets on the indenter's surface can be induced by compressive contact stresses of the order achieved in nanoindentation tests. Finite element analysis (FEA) and MD simulations of nanoindentation reveal that the shear stiction provided by the induced covalent bonding restricts relative slip of the graphene sheet at its contact with the indenter, thus initiating a local strain-shielding effect. As a result, subsequent to stress-induced bonding at the graphene-indenter interface, the spatial variation of continuing incremental strain is substantially redistributed, locally shielding the region directly beneath the indenter by limiting the buildup of strain while imparting deformation to the surrounding regions. The extent of strain shielding is governed by the strength of the shear stiction, which depends upon the level of hydrogen saturation at the indenter's surface. We show that at intermediate levels of hydrogen saturation the strain-shielding effect can enable the graphene to support experimentally determined fracture loads and displacements without prematurely reaching locally limiting states of stress and deformation.
Creating Collaborative Third-space Discourse to Address Contradictions in Coteaching

In diesem Beitrag wird untersucht, wie Einwande gegen das "Coteaching" vorgebracht werden, ohne sein rekursives Gegenstuck, den "kogenerativen Dialog", miteinzubeziehen. Um dualistische Tendenzen beim Coteaching zu vermeiden, konnen Teilnehmerinnen und Teilnehmer den kogenerativen Dialog verwenden, um einen kollaborativen drei-dimensionalen Diskurs aufzubauen, in dem Plane fur das kooperative Vorgehen gemeinsam entwickelt werden. Es wird auserdem aufgezeigt, wie die Ubertragung der kosmopolitischen Ethik im Zusammenspiel mit kogenerativen Dialogen verwendet werden kann, um ideologische Differenzen zwischen Coteaching-Praktizierenden zu steuern und fruchtbare Arbeitsbeziehungen aufzubauen. URN: urn:nbn:de:0114-fqs0604198
Job satisfaction and perceived autonomy for nurse practitioners working in nurse‐managed health centers

Purpose More primary care providers are needed to deliver health care to Americans living in poverty and those soon to be insured under the Affordable Care Act. Nurse practitioners (NPs) in nurse-managed health centers (NMHCs) are poised to meet this need. This research study examined the characteristics of NPs working in NMHCs and measured job satisfaction and perceived level of autonomy. No studies about job satisfaction or autonomy for NPs working in NMHCs had been previously reported. Data sources This descriptive, quantitative study surveyed primary care NPs working in NMHCs that are part of the National Nursing Centers Consortium (NNCC). NP e-mail addresses were obtained from NNCC center directors. Of 198 NPs invited to the electronic survey, 99 completed the Misener Nurse Practitioner Job Satisfaction Scale, demographic questionnaire, questions about perceived autonomy, and whether they would recommend working in an NMHC. Participants came from 16 states and 46 NMHCs. Conclusions NPs working in NMHCs have job satisfaction, perceive their role as autonomous, and are satisfied with the autonomy they have. Implications for practice NMHCs can provide access to primary health care for many Americans. More NPs may choose employment in NMHCs for job satisfaction and autonomy.
Micronutrients and Human Immunodeficiency Virus Type 1 Disease Progression among Adults and Children

The results of randomized trials among men and nonpregnant women have confirmed the potential benefits of vitamins B, C, and E supplements on the immune status of human immunodeficiency virus (HIV)-infected individuals. Larger trials are needed to ascertain whether these benefits are sustained and to examine the effect of supplementation on clinical outcomes. Among pregnant women, vitamin A supplements increase the risk of mother-to-child transmission. Supplementation with vitamins B, C, and E during prenatal and breastfeeding periods should be encouraged, in light of the protective effects on adverse pregnancy and child outcomes. In children aged >6 months, vitamin A supplements are beneficial for reducing morbidity and mortality in developing countries, including among HIV-infected children. There are no data on the relationships of other micronutrients and child health. For adults and children, more research is warranted on the role of selenium, zinc, and other trace elements on various measures of health among HIV-infected individuals.
Atypical Depression: Useful Concept, but it's Time to Revise the DSM-IV Criteria

Stewart et al (2009) have outlined the evidence in support of the validity of the DSM-IV definition of the 'With Atypical Features' episode specifier. Although recognizing the historical significance and clinical utility of the concept of atypical depression, this article takes issue with the DSM-IV criteria. It is concluded that mood reactivity, the A or obligative criterion, is neither significantly associated with the other symptomatic criteria nor useful to diagnose atypical depression, and thus should be eliminated. Problems with operationalization, specification, and reliability of ratings of the diagnostic criteria further limit validity. Despite these limitations in classification, many of the features associated with atypical depression are linked to an early onset of affective illness, including trait-like interpersonal sensitivity, comorbid social anxiety and agoraphobia, a history of childhood physical or sexual trauma, and indicators of the 'soft' side of the bipolar spectrum. Neurophysiologic studies also suggest that chronic, early-onset atypical depressions differ from both melancholia and normality. Re-analyses of the Columbia group's seminal studies suggest that preferential response to phenelzine vs imipramine--arguably the strongest validator of atypical depression--similarly appears to be limited to patients with chronic, early-onset syndromes. The criteria for atypical depression need to be revised in DSM-V, including sharpening the operational definitions for the specific symptoms. The importance of age of onset and comorbid anxiety warrant further study. Research examining the validity of a subform of atypical depression characterized by trait-like interpersonal sensitivity and a chronic, early-onset course may further enhance the clinical utility of the DSM-V classification.
Breaking out of the mold: diversity within adult stem cells and their niches

During the past several years, it has become increasingly possible to study adult stem cells in their native territories within tissues. These studies have provided new evidence for the existence of stem cells in the breast, muscle, lung and kidney and have led to a deeper understanding of the best-known stem cells in Drosophila and mice. Tissue stem cells are turning out to be diverse, with varying division rates, lineage lengths, and mechanisms of regulation. In addition, stem cells are now known to engage in a wide variety of interactions with neighboring cells and extracellular matrices, and to respond to various neural and hormonal signals. Stem cell niches are also diverse, sometimes harboring multiple stem cell types. Internally, a stem cell's chromatin and cytoskeletal organization play key roles. Understanding how stem cells and their progeny are controlled will illuminate fundamental biological mechanisms that govern the construction and maintenance of tissues within metazoan animals.
Nicolai maps and fermion sectors

Abstract Nicolai maps, and particularly their fermion sector structure, are explored over a broad variety of supersymmetric theories. Studies are made in the Witten model, the N = 2 supersymmetric sigma model in 1 + 0 dimensions, dimensionally reduced Wess-Zumino models, and N = 1 Yang-Mills in D = 4. In general each theory yields families of Nicolai maps, each map being a Langevin equation, equivalent to the dynamics of a particular sector. We also detail the remarkable fact that closed form Nicolai maps exist for a few ordinary bosonic nonsupersymmetric theories, with ordinary QCD 4 as an important example. These bosonic theories correspond to “null-fermion” sectors of supersymmetric theories, in which the fermions fail to contribute.
Issues in Oral History: Elaboration of Traumatic Events:

Szrmmary.-Two cases of allegoricdl elaboration of traumatic events were scrutinized. The described observations suggcsr that elaboration of real events and the possibhty of their subsequent distor~lonb sllould be considered when interpceting natratives pertaining to issues viewed by society as undesirable. When society prohibits critique of some historical events or makes such critique socially unacceptable, it is hkely that remembrance of these events may take the form of an allegory. With the passage of time, further &stortions of real events may take place to conform the story to the contemporary niueau of a society. Attending a school event in which his daughters participated, the first author observed the children's dramatization of the classical story of the Pied Piper of Hamelm. The script appeared to follow the familiar version of the story: The Pied Piper appeared when the town was infested with rats. For a fee, he played his magic pipe and lured the rats into a river. When the townspeople reneged on the payment, the Pied Piper played his pipe again and led the children of the townspeople away. So far, the school play followed the original story faithfully. However, the conclusion of the play was altered: after being paid by the repenting mayor, the Pied Piper of Hamelin brought the children back.
Use of the ThinPrep® method in bile duct brushings: Analysis of morphologic parameters associated with malignancy and determination of interobserver reliability

Recent work suggests the ThinPrep® method can improve diagnostic sensitivity and accuracy in bile duct brushings. However, the proportion of atypical and suspicious diagnoses remains high. The aim of this study was to identify the most useful morphologic features in ThinPrep® bile duct cytology and evaluate interobserver reliability. We evaluated 100 bile duct brushings prepared by ThinPrep®, all with either histology or long term clinical follow-up (55 malignant, 45 benign). Morphologic features were evaluated by four experienced cytopathologists blind to clinical information and follow-up diagnoses. These features included cellularity, blood or diathesis, mitoses, inflammation, three-dimensional groups, discohesive atypical cells, macronucleoli, well-defined cytoplasmic borders, and nuclear features of malignancy (nuclear membrance irregularity, chromatin clumping). The data were analyzed by intraclass correlation (ICC) and stepwise multiple logistic regression. Reviewers showed unanimous agreement in 29% of cases, one degree of disagreement in 58% of cases, and full disagreement in 13% of cases. Of benign cases, 38% were thought to be diagnostic of malignancy by at least one of the four reviewers. Sensitivity for the morphologic parameters varied from 18 to 67%; the highest sensitivity was for discohesive atypical cells, well-defined cytoplasmic borders, nuclear features of malignancy, and cellularity (67, 62, 51 and 46%, respectively). Specificity of parameters varied from 16 to 100%; the highest specificity was for mitoses, three-dimensional groups, nuclear features of malignancy, and macronucleoli (100, 98, 93, and 93%, respectively). Interobserver reliability (ICC) was very good for specimen cellularity (0.72) and nuclear features of malignancy (0.60). In logistic regression analysis, only nuclear features of malignancy and increasing patient age separated benign from malignant. On ThinPrep® bile duct brushings, nuclear features of malignancy are most useful in distinguishing benign from malignant, and interobserver reliability for this parameter is very good. Discohesive atypical cells show moderate sensitivity and specificity, while three dimensional clusters and macronucleoli are specific but not sensitive for malignancy, and are not significant in multivariate logistic regression models. The relatively high proportion of benign cases thought to be diagnostic of malignancy by at least one reviewer argues for a consensus approach to this diagnosis. Diagn. Cytopathol. 2008;36:651–656. © 2008 Wiley-Liss, Inc.
Integrated Quantum Well Bipolar Devices for Tunable Detection and Optical Logic Applications

The properties of exciton-based quantum well devices suitable for low-power photonic switching and logic applications and wavelength selective detection will be described. The basic device is a heterojunction bipolar transistor with MQW collector region monolithically integrated with a p-i(MQW)-n modulator, realized by single-step epitaxy. The integrated controller-modulator device, by virtue of its unique photocurrent-voltage characteristics, exhibits integrating-thresholding properties. These properties have been exploited to demonstrate cascadability, fan-out, optoelectronic amplification, special logic functions, programmable optical/electronic memory capabilities, and wavelength selective detection with GaAs/AlGaAs heterostructure devices.
Relationship Between the Public’s Belief in Recovery, Level of Mental Illness Stigma, and Previous Contact

Disbelief exits that individuals who have a mental health condition are able to recover and fully function in life. This study analyzed 1,437 adults from the 2006 General Social Survey. Structural equation modeling (1) examined the relationship between respondents’ level of prejudicial attitudes and social distance (i.e., stigma) toward individuals who have a mental health condition and their belief in the potential of recovery (2) tested whether previous contact with an individual who received treatment was a mediator. Findings indicated that the belief in recovery led to lower levels of social distance. Prejudicial attitudes were found to be a predictor of one’s level of social distance. Previous contact was not a mediator however; males, minorities and those with less education were less likely to have had previous contact. Results indicated a need to emphasize the probability of recovering from a mental health condition when developing target-specific stigma reducing strategies.
A comparative study of photosynthetic electron transport in algal cells and spinach chloroplasts.

Steady-state relaxation spectroscopy provides absorption data which may be used to calculate the rates of electron flow through intermediates of the electron transport chain. In chloroplasts, the calculated rates for P700 agree well with measured Hill reaction velocities. The relaxation times of cytochrome and P700 are consistent with current theories of sequential electron transport from cytochrome to P700 in chloroplasts, but not in whole cells of a red and of a blue-green alga. 3-(3,4-Dichlorophenyl)-1, 1-dimethylurea (DCMU) inhibits all activity in chloroplasts while in intact cells electron transport through P700 and cytochrome continues even at a concentration of the inhibitor which eliminates O2 evolution. With 620-nm light, the amplitude of oxidized cytochrome increases upon addition of DCMU partly because its reduction rate declines and partly because quanta are diverted from Photosystem II to Photosystem I. Relaxation times also increase, but this increase can be reversed by further addition of the uncoupler carbonyl cyanide m-chlorophenylhydrazone.
Periodontics in general practice.

Healthy periodontal tissues are the foun­ dation which must be the basis for all dental measures to rebuild and repair after damage has been caused by dental disease. Periodontics, therefore, has a major role in the therapeutic and pre­ ventive phases of dentistry and should be practiced by every general practitioner. Only thus will it be possible for the pro­ fession to alter the present statistics which reveal the exceedingly high incidence of periodontal disease. Epidemiological studies1,2 of perio­ dontal disease have shown that nearly 80 per cent of adults and over 20 per cent of children have inflammatory lesions, varying in degree from marginal gingi­ vitis— localized or general— to the more severe periodontitis simplex and com­ plex. Figure 1 is an example of cases, all too common, where chronic gingival in­ flammation spreads from the gingival crest tissues into the marrow space of the interdental bone, causing resorption of the bone. Unfortunately periodontal le­ sions are so common that many dentists consider them “ normal” — unless they are advanced— and do not try to correct them until the damage is severe and ob­ vious even to the patient. Most periodontists have been asked by the patient referred to them, “How long have I had this condition?” The resorp­ tion of the alveolar crest in cases of chronic periodontitis simplex is usually slow enough that the lesion could have been present for a few years. To be able to detect the pathological condition quickly, first of all the practitioner must have a thorough knowledge of normal histology3 and physiology of the mouth. The common periodontal lesions4 occur as inflammation, which is a cellular and biochemical reaction to a mechanical, bacterial, chemical or traumatic injury. The inflammatory process is a reversible reaction; the affected tissue can be re­ stored to normal condition by removal of the etiological factors. Sir William Osier’s oft quoted statement that “ the practice of medicine is in relation to the knowledge of pathology” may be applied to dentistry. With a knowledge of pa­ thology, the horizon of dentistry becomes unlimited. , In another study it was shown that 65 per cent of adult patients have lost their teeth through periodontal disease.5 This high percentage is evidence of the neces­ sity of giving an important place to pe­ riodontal treatment in the dental care of
Fractal analysis of stealthy pathfinding aesthetics

This paper uses a fractal model to analyze aesthetic values of a new class of obstacle-prone or "stealthy" pathfinding which seeks to avoid detection, exposure, openness, and so forth in videogames. This study is important since in general the artificial intelligence literature has given relatively little attention to aesthetic outcomes in pathfinding. The data we report, according to the fractal model, suggests that stealthy paths are statistically significantly unique in relative aesthetic value when compared to control paths. We show furthermore that paths generated with different stealth regimes are also statistically significantly unique. These conclusions are supported by statistical analysis of model results on experimental trials involving pathfinding in randomly generated, multiroom virtual worlds.
Hurricane vulnerability modeling: Development and future trends

Abstract Catastrophe models help to evaluate the vulnerability of the building stock exposed to a hazard. This paper presents a history of the hurricane risk models in Florida, and discusses their relationship to the building codes. The first models were econometric, and failed to predict the insured building losses produced by hurricane Andrew. This led to a change in the loss projection paradigm and to the advent of modern catastrophe modeling. Advantages and challenges of the current methodologies are discussed, including the quality of input, validation, uncertainty, and scope of the outputs. The paper concludes with a brief overview of current and future research in vulnerability modeling.
Cellular metabolism of brevetoxin (PbTx-2) by a monocyte cell line (U-937)

Blooms of Karenia brevis produce brevetoxins which cause neurotoxic shellfish poisoning and respiratory symptoms in humans as well as harmful effects on sea life. To investigate potential effects of brevetoxins on immune system components, a monocyte cell line (U-937) was exposed in vitro to PbTx-2. U-937 cells metabolized PbTx-2 through cellular detoxification mechanisms, as evidenced by depletion of intracellular glutathione and formation of glutathione and cysteine conjugates. Total intracellular glutathione was significantly decreased in toxin-treated cells compared to control cells, as measured using an enzymatic recycling method. LC/MS was used to detect the following brevetoxin metabolites: a cysteine-PbTx-2 conjugate (m/z 1018) and two putative glutathione-PbTx-2 conjugates (m/z 1204 and 1222). During 3h incubation, glutathione conjugates were detectable as early as 1h and increased in concentration after 2 and 3h. A cysteine-PbTx-2 conjugate appeared after 2h and increased in concentration after 3h. Detectable levels of brevetoxin conjugates were present in response to toxin concentrations of 1muM. Depletion of intracellular glutathione and formation of brevetoxin metabolites, with changes in concentrations over time, suggest immune cells (U-937) have important cellular detoxification pathways for PbTx-2.
Development of an optimal X-ray beam for dual-mode emission and transmission mammotomography

Abstract Objectives : A dual-mode Single Photon Emission Computed Tomography (SPECT)/X-ray CT (XCT) system for full-field mammotomography is proposed for evaluation of breast lesions, where dual-view X-ray mammography has proven to be ineffective or inconclusive, particularly in radiographically dense breasts. Investigated design parameters include combined SPECT/XCT system geometry, X-ray focal spot size, tube loading, kVp, filtration, and detector type to determine operating parameters for a novel quasi-monochromatic X-ray beam for use in X-ray computed mammotomography that would use a dose equal to that from dual view mammography and that could be combined in a dual-mode system with SPECT. Methods: The relatively compact design of the hybrid SPECT/XCT will allow both systems to rotate on the same gantry below a patient. The hybrid system will be composed of a versatile, goniometer-based SPECT gantry, and an XCT system with a fixed position tungsten target, cone-beam geometry and digital flat panel detector frame nearly orthogonal to the SPECT system. The X-ray beam was modeled by xSpect, a semi-empirical simulation code for X-ray production, attenuation, and detection. The idealized operating parameters for the quasi-monochromatic beam were determined by evaluating a beam hardening (minimum) figure of merit (FOM) along with quantitative spectral characteristics, and an exposure efficiency (maximum) FOM. These FOMs were evaluated in 8–16 cm thick uncompressed breasts. Filters with atomic numbers ( Z ) from 51–65 with 10th to 1000th value attenuating layer thicknesses were modeled, while considering tube loading limitations. Results: Using a tungsten target, increased tube potential and filtration can yield minimal beam hardening with improved exposure efficiency and contrast for various thicknesses of uncompressed breasts. Optimal tube operating range between 50–70 kVp with filter thickness of between 100th and 500th value layer for Z filters 56–62 result in optimized FOMs while remaining at or below expected dose of two-view X-ray mammography for the entire breast. Mean quasi-monochromatic beam energies were near 40 keV, with beam widths of Z =65 and for thicknesses greater than the 500th value layer. Heavy filtration also demonstrated near-independence of FOM outcomes based on breast size. Conclusion: Simulated data show that a quasi-monochromatic beam with minimal beam hardening can readily be generated. Given the small expected source-image distance, it is geometrically feasible for the XCT system to be mounted on the SPECT gantry so that simultaneous SPECT/XCT images of a pendant, uncompressed breast can be obtained with identical imaging geometries.
An Empirical Theory of Rational Nominating Behaviour Applied to Japanese District Elections

Plurality electoral systems with multi-member districts and single nontransferable votes (SNTV) allow parties to win multiple seats in district elections by nominating multiple candidates, but they also penalize a party's seat share if the number of candidates offered is ‘too many’ or ‘too few’. Given an institutional incentive to nominate the ‘correct’ number of candidates, we seek to establish empirically that the nominating behaviour of parties in such systems results from a rational calculus of strategic choice. So we develop and test an empirical theory of rational nominating behaviour applied to Japanese district elections before the 1994 electoral reform. We establish, for all possible nominating strategies, the conditions on voting outcomes required for actors to maximize benefits in the context. The efficiency of actual strategy choices for maximizing benefits is found by comparing an observed outcome from voting (the distributed benefit) with the benefit that would be expected had the party chosen its ‘best’ alternative nominating strategy instead. Empirical testing indicates that Japanese parties discriminated between available nominating strategies and made choices that maximized benefits in the context, evidence that the nominating behaviour of parties in this test environment was based on rational calculation.
An improved linear placement algorithm using node compaction

Linear placement has several applications in the design of very large scale integrated (VLSI) circuits. Several authors have recently shown that node clustering or compaction enhances the performance of iterative algorithms. This paper describes a technique to extract clusters by means of an algorithm that identifies a maximum weight matching in a path graph in linear time. The resulting linear placement algorithm (CLP) combines node compactions and iterative improvement in an efficient and effective approach. The benefit of compaction is quite visible. Comparisons of the results of CLP with and without compaction on several test cases show the dramatic effect of compaction on the final solution. The approach of CLP is an efficient improvement of the linear placement algorithm of Saab and Chen [1994]. On many instances with known optimal solutions, CLP also achieves an optimal solution. The dependency of the results of CLP on the initial placement is minimal, since solutions found by CLP using many different starts do not significantly differ from each other. Under suitable assumption, CLP can be shown to run in O(nP), where n and P are the number of nodes and the number of pins of the input circuit, respectively.
Influence of Tightly Bound Mg2+ and Ca2+, Nucleotides, and Phalloidin on the Microsecond Torsional Flexibility of F-Actin†

To better understand the relationship between structure and molecular dynamics in F-actin, we have monitored the torsional flexibility of actin filaments as a function of the type of tightly bound divalent cation (Ca2+ or Mg2+) or nucleotide (ATP or ADP), the level of inorganic phosphate and analogues, KCl concentration, and the level of phalloidin. Torsional flexibility on the microsecond time scale was monitored by measuring the steady-state phosphorescence emission anisotropy (rFA) of the triplet probe erythrosin-5-iodoacetamide covalently bound to Cys-374 of skeletal muscle actin; extrapolations to an infinite actin concentration corrected the measured anisotropy values for the influence of variable amounts of rotationally mobile G-actin in solution. The type of tightly bound divalent cation modulated the torsional flexibility of F-actin polymerized in the presence of ATP; filaments with Mg2+ bound (rFA = 0.066) at the active site cleft were more flexible than those with Ca2+ bound (rFA = 0.083). Filaments prepared from G-actin in the presence of MgADP were more flexible (rFA = 0.051) than those polymerized with MgATP; the addition of exogenous inorganic phosphate or beryllium trifluoride to ADP filaments, however, decreased the filament flexibility (increased the anisotropy) to that seen in the presence of MgATP. While variations in KCl concentration from 0 to 150 mM did not modulate the torsional flexibility of the filament, the binding of phalloidin decreased the torsional flexibility of all filaments regardless of the type of cation or nucleotide bound at the active site. These results emphasize the dynamic malleability of the actin filament, the role of the cation-nucleotide complex in modulating the torsional flexibility, and suggest that the structural differences that have previously been seen in electron micrographs of actin filaments manifest themselves as differences in torsional flexibility of the filament.
Graph theory and statistical physics

A graph theoretic formulation of the Ising, percolation and graph colouring problems is given, and it is shown that the solution to all three problems is derivable from the Whitney rank function. The Mobius inversion technique is illustrated in the context of the colouring problem using both the lattice of all subgraphs and the lattice of only bond closed subgraphs of a graph. It is pointed out that, in statistical mechanics, the lattice of all connected subgraphs is more useful than either of these, and its Mobius function is given. The weight factors in the resulting linked-cluster expansion of the Whitney rank function are discussed, special consideration being given to the mean number of clusters. The duality relation for the rank function is derived from Minty's theorem and the theorem is extended to enable a similar relation for the site problem to be obtained.
Src-mediated caveolin-1 phosphorylation regulates intestinal epithelial restitution by altering Ca2+ influx after wounding

Early mucosal restitution occurs as a consequence of intestinal epithelial cell (IEC) migration to reseal superficial wounds, but its exact mechanism remains largely unknown. Caveolin-1 (Cav1), a major component associated with caveolar lipid rafts in the plasma membrane, is implicated in many aspects of cellular functions. This study determined if c-Src kinase (Src)-induced Cav1 phosphorylation promotes intestinal epithelial restitution after wounding by activating Cav1-mediated Ca2+ signaling. Src directly interacted with Cav1, formed Cav1-Src complexes, and phosphorylated Cav1 in IECs. Inhibition of Src activity by its chemical inhibitor PP2 or suppression of the functional caveolin scaffolding domain by caveolin-scaffolding domain peptides prevented Cav1-Src interaction, reduced Cav1 phosphorylation, decreased Ca2+ influx, and inhibited cell migration after wounding. Disruption of caveolar lipid raft microdomains by methyl-β-cyclodextrin reduced Cav1-mediated Ca2+ influx and repressed epithelial restitution. Moreover, Src silencing prevented subcellular redistribution of phosphorylated Cav1 in migrating IECs. These results indicate that Src-induced Cav1 phosphorylation stimulates epithelial restitution by increasing Cav1-mediated Ca2+ signaling after wounding, thus contributing to the maintenance of gut mucosal integrity under various pathological conditions.
Novel computational methods for the determination of partition coefficients by planar chromatography

Abstract An evaluation of an empirical method for the determination of log P values for 24 phenols by thin-layer chromatography is described. Separation is on bonded C8 plates and aqueous methanol is used as the mobile phase. The method is based on the Soczewinski equation and uses standards to define a solvent composition at which RM is equal to log P. In addition, a new approach, based on a paired t-test is described. The t-statistic is used to compare the differences between the literature log P values and the computed RM values over a range of solvent compositions. The p-value corresponding to the t-score can then be used as the measure of agreement between the computed and chromatographic values of log P. The mean difference between the estimated and the literature log P values varies between 0.1 and 0.2 of a log P unit, depending on the method used.
Preparation of UDP-D-(U-14C)galacturonic acid and UDP-D-(6-3H)galactose with high specific activities.

Abstract Simple procedures for the preparation of UDP- d -[U- 14 C]galacturonic acid and UDP- d -[6- 3 H]galactose with high specific activities are described. The conversion involves the enzymatic oxidation of the appropriate UDP- d -galactose derivative to UDP- d -galactose-6-aldehyde followed by either further oxidation with iodine or reduction with sodium borotritide. The labeled products were isolated from reaction mixtures by ion exchange and paper chromatography.
New Plant Introductions with Resistance to the Soybean Aphid

The soybean aphid (SA; Aphis glycines Mat- sumura) was fi rst found in the northern soybean (Glycine max (L.) Merr.) growing regions of the United States in 2000. By 2005, the aphids had spread to 23 soybean growing states reaching as far south as Mississippi and Georgia and also north into Ontario, Canada. The objective of this study was to identify new sources of resistance to the SA. Nearly 200 soybean genotypes (cul- tivars, breeding lines, and plant introductions (PIs)) were screened for resistance to SA in a greenhouse choice test using SA collected in Wooster, OH. Three PIs (PI 243540, PI 567301B, and PI 567324) were identifi ed as resistant while six PIs were identifi ed as moderately resistant. The fi ndings on the three resistant and three of the six moderately resistant PIs were confi rmed through further fi eld and greenhouse tests. PI 243540 displayed strong antibiosis resistance such that SA was unable to survive on this PI in a no-choice test. The other two resistant PIs possessed mainly antixenosis type resistance. PI 243540 and PI 567301B were also resistant to the SA collection from Illinois. The aphid resistant PIs identifi ed in this study will be useful in efforts to develop aphid-resistant soybean cultivars.
Convex Models of High Dimensional Discrete Data

Categorical data of high (but finite) dimensionality generate sparsely populated J-way contingency tables because of finite sample sizes. A model representing such data by a "smooth" low dimensional parametric structure using a "natural" metric would be useful. We discuss a model using a metric determined by convex sets to represent moments of a discrete distribution to order J. The model is shown, from theorems on convex polytopes, to depend only on the linear space spanned by the convex set—it is otherwise measure invariant. We provide an empirical example to illustrate the maximum likelihood estimation of parameters of a particular statistical application (Grade of Membership analysis) of such a model.
Delayed Light Emission as an Indicator of Cantaloupe Maturity

Saticoy cantaloupes at six stages of maturity were evaluated for differences in delayed light emission (DLE), chlorophyll, and soluble solids. DLE varied significantly and predictably by stage of maturity indicating its potential as a rapid, nondestructive method for measuring cantaloupe maturity.
Informed policy making for the prevention of unwanted pregnancy. Understanding low-income women's experiences with family planning.

California health and welfare officials asked the authors to identify ways that their programs could encourage service use among low-income women. The project posed a challenge: The clients wanted to identify supply-side barriers amenable to intervention, but prior research suggested other factors might be more influential. The approach was to examine service-related issues, but in the broader context of women's experiences. The authors identify factors amenable to intervention, including inaccurate beliefs about methods. Other important influences—such as instability of relationships, skepticism about planning, or unsatisfactory method experiences—may be beyond the reach of specific policies, but are nevertheless critical to understanding program context. Findings suggest that punitive messages and policies based on a simplistic model of behavior may be unrealistic and ineffective.
Analysis of Multiple Response in Marketing Research: Estimating the Degree of Association

Researchers often are forced to analyze nominally-scaled multiple response questions for which respondents have provided more than one response. A Multiple Index of Predictive Association (MIPA) is derived for estimating the effect of the independent variable on the dependent variable when one or both variables have multiple responses. MIPA is illustrated using demographic and preference data. The relevance of the Multiple Index of Predictive Association to marketing and its implications are discussed.
Quantification of myocardial perfusion using CMR with a radial data acquisition: comparison with a dual-bolus method

Quantitative estimates of myocardial perfusion generally require accurate measurement of the arterial input function (AIF). The saturation of signal intensity in the blood that occurs with most doses of contrast agent makes obtaining an accurate AIF challenging. This work seeks to evaluate the performance of a method that uses a radial k-space perfusion sequence and multiple saturation recovery times (SRT) to quantify myocardial perfusion with cardiovascular magnetic resonance (CMR). Perfusion CMR was performed at 3 Tesla with a saturation recovery radial turboFLASH sequence with 72 rays. Fourteen subjects were given a low dose (0.004 mmol/kg) of dilute (1/5 concentration) contrast agent (Gd-BOPTA) and then a higher non-dilute dose of the same volume (0.02 mmol/kg). AIFs were calculated from the blood signal in three sub-images with differing effective saturation recovery times. The full and sub-images were reconstructed iteratively with a total variation constraint. The images from the full 72 ray data were processed to obtain six tissue enhancement curves in two slices of the left ventricle in each subject. A 2-compartment model was used to determine absolute flows The proposed multi-SRT method resulted in AIFs that were similar to those obtained with the dual-bolus method. Myocardial blood flow (MBF) estimates from the dual-bolus and the multi-SRT methods were related by MBF multi-SRT = 0.85MBF dual-bolus + 0.18 (r = 0.91). The multi-SRT method, which uses a radial k-space perfusion sequence, can be used to obtain an accurate AIF and thus quantify myocardial perfusion for doses of contrast agent that result in a relatively saturated AIF.
Seismic Analysis of Integral Abutment Bridge in Tennessee, Including Soil–Structure Interaction:

Integral abutment bridges are jointless bridges in which the deck is continuous and connected monolithically with the abutment walls, supported typically by a single row of piles. Part of the research results from an ongoing project focus on the effects of two major parameters on the seismic behavior of an integral abutment bridge in Tennessee. The soil-structure interaction around the piles and in back of the abutments is considered, namely, clay stiffness (medium versus hard) around the piles and level of compaction (loose versus dense) of the abutment wall backfilling. Modal and nonlinear time-history analyses were performed on a three-dimensional detailed bridge model with the commercial software SAP2000. These analyses clearly showed that (a) compacting the backfilling of the abutment wall will increase the dominant bridge longitudinal natural frequency considerably more than increasing the foundation clay stiffness; (b) the maximum deflection and bending moment in the piles under seismic loading wil...
β-Relaxation governs protein stability in sugar-glass matrices

The stabilizing effect of sugar-glass matrix materials for freeze-drying proteins or nucleic acids has been variously ascribed to the thermodynamic effect of ‘water replacement’ by sugar molecules or to the kinetic effect of slowed α relaxation associated with sugar matrix vitrification. While evidence for each of these hypotheses exists, we show that neither can adequately account for the observed stabilization of proteins embedded in sugar-glasses. Instead, we find firm evidence that protein stability in these glasses is directly linked to high frequency β relaxation processes of the sugar matrix. Specifically, we observe that when the β relaxation time, τβ, of sugar-glasses is increased with antiplasticizing additives, protein stability increases in linear proportion to the increase in τβ, even though these same additives simultaneously decrease the glass transition temperature, Tg, and the α relaxation time, τα, of the sugar matrix materials. Moreover, we find that while sugars ‘replace’ water by stabilizing protein native-like conformation in the dry state, the resulting enhanced protein conformational stability does not have a significant impact on the degradation rate of the proteins in sugar-glasses. We discuss implications of these findings for the fundamental physics of glass formation and for effective engineering of protein stabilizing glasses through the modification of τβ.
Sustained acceleration of colonic transit following chronic homotypic stress in oxytocin knockout mice

Abstract Acute restraint stress delays gastric emptying and accelerates colonic transit via central corticotropin releasing factor (CRF) in rats. In contrast, central oxytocin has anxiolytic effects and attenuates the hypothalamus–pituitary–adrenal (HPA) axis in response to stress. Our recent study showed that up regulated oxytocin expression attenuates hypothalamic CRF expression and restores impaired gastric motility following chronic homotypic stress in mice. We studied the effects of acute and chronic homotypic stress on colonic transit and hypothalamic CRF mRNA expression in wild type (WT) and oxytocin knockout (OXT-KO) mice. Colonic transit was measured following acute restraint stress or chronic homotypic stress (repeated restraint stress for 5 consecutive days). 51 Cr was injected via a catheter into the proximal colon. Ninety minutes after restraint stress loading, the entire colon was removed. The geometric center (GC) was calculated to evaluate colonic transit. Expression of CRF mRNA in the supraoptic nucleus (SON) was measured by real time RT-PCR. Colonic transit was significantly accelerated following acute stress in WT (GC = 8.1 ± 0.8; n = 7) and OXT KO mice (GC =9.4 ± 0.3; n = 7). The accelerated colonic transit was significantly attenuated in WT mice (GC = 6.6 ± 0.5; n = 9) following chronic homotypic stress while it was still accelerated in OXT KO mice (GC = 9.3 ± 0.5; n = 8). The increase in CRF mRNA expression at the SON was much greater in OXT-KO mice, compared to WT mice following chronic homotypic stress. It is suggested that oxytocin plays a pivotal role in mediating the adaptation mechanism following chronic homotypic stress in mice.
LONGITUDINAL ANALYSIS OF ACTIVITY AND TRAVEL PATTERN DYNAMICS USING GENERALIZED MIXED MARKOV LATENT CLASS MODELS

Abstract Understanding the dynamics of time allocation by households and their household members is becoming increasingly important for travel demand forecasting. A unique opportunity to understand day-to-day and year-to-year behavioral change, is provided by data from multi-day travel diaries combined with yearly observation of the same individuals over time (panel surveys). In fact, the “repeated” nature of the data allows to distinguish units that over time change their behavior from those that are not and to uncover the underlying stochastic behavior generating the data. In this paper data from the Puget Sound Transportation Panel (PSTP) are analyzed to identify change in the patterns of time allocation by the panel participants (i.e., patterns of activity participation and travel). The data analyzed are sequences of states in categorical data from reported individuals' daily activity participation and travel indicators. This is done separately for activity participation and trip making using probabilistic models that generalize the restrictive Markov chain models by incorporating unobserved variables of change. The PSTP data analysis here suggests the more likely presence of multiple paths of change for time allocation to activities, non-stationary switching of activity participation from one year to the next, and day-to-day stationarity in activity participation pattern switching. Travel pattern change is best explained by a single path of change with stationary day-to-day pattern transition probabilities that are different from their year-to-year counterparts.
Use of 3D laser radar for navigation of unmanned aerial and ground vehicles in urban and indoor environments

This paper discusses the integration of Inertial measurements with measurements from a three-dimensional (3D) imaging sensor for position and attitude determination of unmanned aerial vehicles (UAV) and autonomous ground vehicles (AGV) in urban or indoor environments. To enable operation of UAVs and AGVs at any time in any environment a Precision Navigation, Attitude, and Time (PNAT) capability is required that is robust and not solely dependent on the Global Positioning System (GPS). In urban and indoor environments a GPS position capability may not only be unavailable due to shadowing, significant signal attenuation or multipath, but also due to intentional denial or deception. Although deep integration of GPS and Inertial Measurement Unit (IMU) data may prove to be a viable solution an alternative method is being discussed in this paper. The alternative solution is based on 3D imaging sensor technologies such as Flash Ladar (Laser Radar). Flash Ladar technology consists of a modulated laser emitter coupled with a focal plane array detector and the required optics. Like a conventional camera this sensor creates an "image" of the environment, but producing a 2D image where each pixel has associated intensity vales the flash Ladar generates an image where each pixel has an associated range and intensity value. Integration of flash Ladar with the attitude from the IMU allows creation of a 3-D scene. Current low-cost Flash Ladar technology is capable of greater than 100 x 100 pixel resolution with 5 mm depth resolution at a 30 Hz frame rate. The proposed algorithm first converts the 3D imaging sensor measurements to a point cloud of the 3D, next, significant environmental features such as planar features (walls), line features or point features (corners) are extracted and associated from one 3D imaging sensor frame to the next. Finally, characteristics of these features such as the normal or direction vectors are used to compute the platform position and attitude changes. These "delta" position and attitudes are then used calibrate the IMU. Note, that the IMU is not only required to form the point cloud of the environment expressed in the navigation frame, but also to perform association of the features from one flash Ladar frame to the next. This paper will discuss the performance of the proposed 3D imaging sensor feature extraction, position change estimator and attitude change estimator using both simulator data and data collected from a moving platform in an indoor environment. The former consists of data from a simulated IMU and flash Ladar installed on an aerial vehicle for various trajectories through an urban environment. The latter consists of measurements from a CSEM Swissranger 3D imaging sensor and a MicroStrain low-cost IMU. Data was collected on a manually operated aerial vehicle inside the Ohio University School of Electrical Engineering and Computer Science building.