cssi/SciSciGPT-SciSciNet huggingface dataset:
Construction of di-scFv through a trivalent alkyne-azide 1,3-dipolar cycloaddition

Heterofunctional azide and alkyne PEG-linkers have been synthesized and site specifically conjugated to scFv via a reactive thiol functionality; two scFv were coupled by copper catalyzed 1,3-dipolar cycloaddition to make divalent scFv (di-scFv) with an inter-scFv distance defined to provide divalent binding; antigen binding was maintained for the di-scFv construct and increased several times compared to that of the parent scFv; the cycloaddition reaction reported herein represents an important ligation strategy to covalently link macromolecular proteins and retain sensitive structural conformations.
Catalytic hydrodechlorination of trichloroethylene in water with supported CMC-stabilized palladium nanoparticles.

Abstract In this work, we developed and tested a new class of supported Pd catalysts by immobilizing CMC (carboxymethyl cellulose) stabilized Pd nanoparticles onto alumina support. The alumina supported Pd nanoparticles were able to facilitate rapid and complete hydrodechlorination of TCE (trichloroethylene) without intermediate by-products detected. With a Pd mass loading of 0.33 wt% of the alumina mass, the observed pseudo first order reaction rate constant, k obs , for the catalyst was increased from 28 to 109 L/min/g when CMC concentration was raised from 0.005 to 0.15 wt%. The activity increase was in accord with an increase of the Pd dispersion (measured via CO chemisorption) from 30.4% to 45.1%. Compared to the commercial alumina supported Pd, which has a lower Pd dispersion of 21%, our CMC-stabilized Pd nanoparticles offered more than 7 times greater activity. Pre-calcination treatment of the supported catalyst resulted in minor drop in activity, yet greatly reduced bleeding (
Twenty-year perspective of randomized controlled trials for surgery of chronic nonspecific low back pain: citation bias and tangential knowledge

Abstract Background context After decades of clinical research, the role of surgery for chronic nonspecific low back pain (CNLBP) remains equivocal. Despite significant intellectual, human, and economic investments into randomized controlled trials (RCTs) in the past two decades, the role of surgery in the treatment for CNLBP has not been clarified. Purpose To delineate the historical research agenda of surgical RCTs for CNLBP performed between 1993 and 2012 investigating whether conclusions from earlier published trials influenced the choice of research questions of subsequent RCTs on elucidating the role of surgery in the management of CNLBP. Study design Literature review. Methods We searched the literature for all RCTs involving surgery for CNLBP. We reviewed relevant studies to identify the study question, comparator arms, and sample size. Randomized controlled trials were classified as “indication” trials if they evaluated the effectiveness of surgical therapy versus nonoperative care or as “technical” if they compared different surgical techniques, adjuncts, or procedures. We used citation analysis to determine the impact of trials on subsequent research in the field. Results Altogether 33 technical RCTs (3,790 patients) and 6 indication RCTs (981 patients) have been performed. Since 2007, despite the unclear benefits of surgery reported by the first four indication trials published in 2001 to 2006, technical trials have continued to predominate (16 vs. 2). Of the technical trials, types of instrumentation (13 trials, 1,332 patients), bone graft materials and substitutes (11 trials, 833 patients), and disc arthroplasty versus fusion (5 trials, 1,337 patients) were the most common comparisons made. Surgeon authors have predominantly cited one of the indication trials that reported more favorable results for surgery, despite a lack of superior methodology or sample size. Trials evaluating bone morphogenic protein, instrumentation, and disc arthroplasty were all cited more frequently than the largest trial of surgical versus nonsurgical therapy. Conclusions The research agenda of RCTs for surgery of CNLBP has not changed substantially in the last 20 years. Technical trials evaluating nuances of surgical techniques significantly predominate. Despite the publication of four RCTs reporting equivocal benefits of surgery for CNLBP between 2001 and 2006, there was no change in the research agenda of subsequent RCTs, and technical trials continued to outnumber indication trials. Rather than clarifying what, if any, indications for surgery exist, investigators in the field continue to analyze variations in surgical technique, which will probably have relatively little impact on patient outcomes. As a result, clinicians unfortunately have little evidence to advise patients regarding surgical intervention for CNLBP.
Gravel imbrication on the deflating backshores of beaches on Prince Edward Island, Canada

Abstract Discoidal- to prolate-shaped pebble- to cobble-size clasts on the partially deflated beach backshore of the north shore of Prince Edward Island display a pronounced imbrication. The direction of imbrication correlates with the orientation of wind-shadow sand ridges behind the clasts. The imbrication is created by the selective removal of sand particles beneath the upwind margins of the clasts during deflation. This fabric can be preserved and has the potential to provide a means for the measure of paleowind orientation in partially deflated deposits in shoreline and possibly interdune areas.
Observation of magnetically quenchable positronium-like systems in λ-Al2O3

Abstract The presence of a magnetically quenchable positronium-like compound was observed at or near the internal grain surface boundaries of λ-Al 2 O 3 when positrons were stopped in a power pellet specimen. A 38% change in τ 3 , the orthopositronium lifetime component, when the grain surfaces are saturated with an overlayer of absorbed gases in the presence of a 13 kG quenching field is strong evidence for a new weakly bound surface final state for the positron. Good agreement is obtained between our results and the calculated values for the lifetime and quenching fraction for positronium in the field when the overlayer of gas is removed by calcining. These results suggest systems ( − O 2 , Ps), ( − OH, e + ) adn ( − OH, Ps).
Chemical Tuning of the Electronic Properties of Nanostructured Semiconductor Films Formed through Surfactant Templating of Zintl Cluster

Inorganic/organic coassembly provides a powerful route to the formation of periodic, nanostructured materials. In this work, the surfactant cetyltriethylammonium bromide is used as an organic structure directing agent, and the inorganic phase is formed from the condensation of metal cations with reduced main group clusters know as Zintl clusters. These anionic clusters are formed by alloying alkali metals with various main group elements. The chalcogenide-based Zintl clusters used here have an affinity for gold and other transition metals and will thus nucleate the formation of films on metal surfaces. Interface nucleated inorganic/organic co-organization results in thin films with the periodicity of a liquid crystal phase, but with a cross-linking inorganic network surrounding the surfactant domains. In this work, we investigate the extent to which the band structure of these films can be tuned by altering the elemental composition of the inorganic framework of these periodic nanocomposites. For the semi...
Evaluation of Gas-Phase Rearrangement and Competing Fragmentation Reactions on Protein Phosphorylation Site Assignment Using Collision Induced Dissociation-MS/MS and MS3

The development of strategies directed toward comprehensive analysis of the phosphoproteome have undoubtedly been facilitated by recent advances in the application of ion trap tandem mass spectrometry-based techniques for routine phosphopeptide identification. However, when multiple potential sites of phosphorylation exist within a phosphorylated peptide sequence, unambiguous characterization of the site of phosphorylation remains a significant challenge. Here, the gas-phase fragmentation reactions of a series of 33 synthetic phospho-serine, -threonine, and -tyrosine peptides containing multiple potential phosphorylation sites have been examined using collision induced dissociation (CID) and multistage tandem mass spectrometry (MS/MS and MS(3)) in a linear quadrupole ion trap. From this study, 15 of the peptides (45%) gave rise to product ions that were formed following initial transfer of a phosphate group from the phosphorylated residue to an unmodified hydroxyl-containing amino acid residue upon CID-MS/MS. The propensity for this rearrangement was found to be highly dependent on the precursor ion charge state and amino acid composition (i.e, proton mobility) of the peptide and was observed predominantly for peptides under "nonmobile" or "partially mobile" protonation conditions. The observation of these rearrangement reactions and/or the lack of product ions that provided definitive evidence for the correct site of phosphorylation, limited the ability to unambiguously assign the correct site of phosphorylation to only 12 of the 33 peptides (36%). Furthermore, the observation of competing fragmentation reactions for the neutral loss of 98 Da from these precursor ions (i.e., the loss of H(3)PO(4) versus the combined losses of HPO(3) and H(2)O) indicates that CID-MS(3) of [M + nH - 98](n+) ions may not be used for unambiguous phosphorylation site localization.
On generalized donating regions: Classifying Lagrangian fluxing particles through a fixed curve in the plane

Abstract For a fixed simple curve in a nonautonomous flow, the fluxing index of a passively-advected Lagrangian particle is the total number of times it goes across the curve within a given time interval. Such indices naturally induce flux sets, equivalence classes of the particles at the initial time. This line of research mainly concerns donating regions, the explicit construction of the flux sets from a sufficiently continuous velocity field. In the author's previous paper (Zhang, 2013 [13] ) the flux sets with indices ±1 were constructed from characteristic curves of the flow field. This work generalizes the notion of donating regions and shows that flux sets are index-by-index equivalent to the generalized donating regions for any finite integer index, provided that the two backward streaklines seeded at the two endpoints of the simple curve neither intersect nor self-intersect. All Lagrangian particles marked by their initial positions are thus classified by their fluxing indices.
EFFECTS OF GENDER AND AGE ON THE CARDIAC BARORECEPTOR REFLEX IN HYPERTENSION

The present study examined whether alterations in the cardiac baroreceptor reflex in hypertension may be a function of constitutional differences associated with gender and age. These hypotheses were tested using a cross-sectional design that compared 20 normotensive and 21 hypertensive men and women of varying age for differences in baroreceptor reflex sensitivity and response latency for heart rate, obtained using a modified bolus phenylephrine (Oxford) method. Relative to their respective normotensive controls, baroreceptor reflex sensitivity was reduced in hypertensive men, but not in hypertensive women. Among normotensive subjects, men had greater baroreceptor reflex sensitivity than women. Independent from the effects associated with differences in blood pressure, age was not a significant predictor of reduction in baroreceptor reflex sensitivity. However, a combination of high blood pressure and older age was associated with a significant increase in baroreceptor reflex response time. In summary, gender and aging interacted with hypertension to alter two different aspects of the baroreceptor reflex. These results provide a preliminary indication that a decline in arterial baroreflex sensitivity may be more specific to hypertension in men than in women. Prolongation in baroreflex response latency in older hypertensive subjects also suggested that aging and hypertension may have a synergistic effect on cardiac parasympathetic function.
Sample size for measuring grammaticality in preschool children from picture-elicited language samples.

Purpose The purpose of this study was to investigate whether a shorter language sample elicited with fewer pictures (i.e., 7) would yield a percent grammatical utterances (PGU) score similar to that computed from a longer language sample elicited with 15 pictures for 3-year-old children. Method Language samples were elicited by asking forty 3-year-old children with varying language skills to talk about pictures in response to prompts. PGU scores were computed for each of two 7-picture sets and for the full set of 15 pictures. Results PGU scores for the two 7-picture sets did not differ significantly from, and were highly correlated with, PGU scores for the full set and with each other. Agreement for making pass–fail decisions between each 7-picture set and the full set and between the two 7-picture sets ranged from 80% to 100%. Conclusion The current study suggests that the PGU measure is robust enough that it can be computed on the basis of 7, at least in 3-year-old children whose language samples were e...
Multiple DNA processing reactions underlie Tn7 transposition.

Abstract The bacterial transposon Tn 7 uses a cut and paste mechanism to translocate between non-homologous insertion sites. In the first step of recombination, double-strand breaks at each transposon end disconnect the element from the donor backbone; in the second step, the now exposed 3′ transposon ends join to the target DNA. To dissect the chemical steps in these reactions, we have used mutant transposons altered at and near their extreme termini. We find that the initiating double-strand breaks result from a collaboration of two distinct DNA strand processing activities, one mediating cleavages at the 3′ ends of Tn 7 , which can be blocked by changes at the transposon tips, and another mediating cleavages at the 5′ ends. The joining of exposed 3′ transposon ends to the target DNA can be blocked by changing the transposon tips. Our results suggest that the target joining step occurs through two usually concerted, but actually separable, reactions in which individual 3′ transposon ends are joined to separate strands of the target DNA. Thus Tn 7 transposition involves several distinct DNA processing reactions: strand cleavage and strand transfer reactions at the 3′ ends of the transposon, and separate strand cleavage reactions at the 5′ ends of the transposon.
The assessment cycle: a model for learning through peer assessment

This paper advances a model describing how peer assessment supports self-assessment. Although prior research demonstrates that peer assessment promotes self-assessment, the connection between these two activities is underspecified. This model, the assessment cycle, draws from theories of self-assessment to elaborate how learning takes place through peer assessment. The model is applied to three activity structures described in the literature to analyse their potential to support learning by promoting self-assessment. Broadly speaking, the model can be used to understand learning that takes place in a variety of peer assessment activities: marking/grading, analysis, feedback, conferencing and revision. This approach contrasts most studies on peer assessment, which have focused on calibration of instructor and peer grades, rather than learning opportunities.
Bronchioloalveolar carcinoma is not associated with younger age at diagnosis: an analysis of the SEER database.

Introduction Bronchioloalveolar carcinoma (BAC) is a unique subtype of non-small cell lung cancer (NSCLC) that is associated with female gender, Asian ethnicity, and never-smoking status. Although BAC is commonly reported to occur more frequently in young people with lung cancer, there is a lack of evidence to support this association. Methods We analyzed the association between age at diagnosis and NSCLC histology among 293,417 incident cases of NSCLC in the Surveillance Epidemiology, and End Results (SEER) database during the years 1973 to 2002. Results The mean age of patients with BAC (66.99 years) was similar to the mean age of all patients with NSCLC (66.44 years). The proportion of patients younger than 50 years of age was significantly smaller among patients with BAC than the overall cohort (6.06% compared with 6.90%). Although a greater percentage of women and Asian patients with lung cancer were younger than 50 years old, the proportion of patients with BAC was similar to the proportion of men and non-Asians with BAC. Finally, the prevalence of BAC histology among patients younger than 50 years did not change significantly after revision of the 1999 World Health Organization pathologic criteria for the diagnosis of BAC (risk ratio 0.93 versus 0.87, p = 0.31). Conclusion BAC is not associated with a younger mean age at diagnosis, nor is it associated with an age of less than 50 years at diagnosis. Patients with mixed BAC probably have similar age characteristics compared with patients with pure BAC.
Variables related to patterns of union Stewards’ commitment

This article examines whether the union and employer commitment of stewards can be predicted by the same antecedent factors and whether any o f those factors are related to dual or unilateral commitment. It modifies a conceptual framework of organizational commitment to recognize the presence of a union and then applies that framework to both union and employer commitment. The analysis found that the predictors of union and employer commitment were mostly different, and structural characteristics of the union, employer, and work significantly differentiated between stewards with high and low dual commitment and between standards with high and low unilateral commitment.
PHP12: ACUTE CARE ELDERLY UNITS: THEIR PREVALENCE, CHARACTERISTICS AND DETERMINANTS

BACKGROUND: The acutely ill hospitalized elderly patients face the risk of functional decline and poor quality care. To improve the outcomes of hospitalization, various intervention models have been used. However, the contributors to the functional loss and quality of care are interrelated and warrant a multidimensional intervention. The Acute Care for Elders (ACE) unit is a one such promising model of care for elderly to minimize adverse outcomes of hospitalization. OBJECTIVE: To analyze the determinants, prevalence and characteristics of ACE units. METHODS: We surveyed all established Geriatric Medicine Divisions (n = 100) across US to determine presence of ACE unit. Data on demographics, resource, structure, administration, and patient care was obtained via a questionnaire. Hospital data regarding number of beds, revenue, number of medicare inpatients, and average length of stay was obtained from Annual Survey data of the American Hospital Association. Descriptive analysis and step-wise logistic regression were used to analyze the characteristics and determinants of ACE units. RESULTS: Of the 82 responding geriatric divisions, 15 had an active ACE unit. Average daily census on ACE units ranged from 5 to 25, average length of stay was 5.2 days and the average nurse to patient ratio was 1:6. Community dwelling was the most common pre-admission living setting. Two most common admitting diagnoses were congestive heart failure and pneumonia. T-test showed significant difference (<.05) between hospitals with ACE unit and hospitals without, with respect to number of beds and total revenue. The step-wise logistic regression indicated that total hospital revenue was the only significant factor in determining the presence of an ACE unit. CONCLUSIONS: Thus, application of the ACE unit model remains modest given the paucity of information regarding its long and short-term benefits and cost-effectiveness. Further research in this direction can facilitate informed policy decisions.
Physical properties of water in Zizania embryos in relation to maturity status, water content and temperature

Changes in the properties of water in excised embryos were measured during the late stages of grain development in two cultivars of Zizania palustris and a population of the endangered species Z. texana. The relationships between water content and water activity were determined from water sorption isotherms, measured at temperatures between 35 and 5°C and then derived for lower temperatures. The freezing and melting behaviour of water in embryos at different water contents was determined using differential scanning calorimetry. The moisture content of embryos at high water activities decreased with maturation, as did the moisture content at which freezing transitions were not observed. While the temperatures of freezing and melting transitions decreased as the moisture content of embryos decreased, there were no discernible differences among embryos at different developmental stages. The properties of water measured in maturing Zizania embryos approached those for orthodox seeds as determined from the strength of water sorption, the enthalpy of the melting transition and the moisture content at which water is unfreezable. From these data we conclude that the properties of water in recalcitrant Zizania embryos change with development to resemble those of embryos of desiccation-tolerant seeds, but that the seeds never achieve the orthodox condition. The effects of interactions between moisture content and temperature on desiccation damage, freezing damage and germination in Zizania are predicted, based on the physical properties of water reported here and the correspondence of these properties with physiological function reported for other species. The resulting ‘phase diagram’ defines possible combinations of moisture content and temperature for storage under equilibrium conditions.
Untangled Web: Internet Use during the 1998 Election

During the 1996 election cycle, candidates for public office began to use the Internet as a campaign tool (Browning 1996; Casey 1996; Rash 1997). As Internet use grew among the general population, it was reasonable to expect that the 1998 election cycle would see increased use of this new medium by political candidates, and new methods and techniques developed to exploit its capabilities.In increasing numbers, House and Senate candidates campaigned along the information superhighway in 1998. While very few candidates had web sites in previous elections (Browning 1996), by October 1998 more than two-thirds of the candidates for U.S. Senate and for U.S. House open seats had established web sites. In the past, candidate web sites were little more than digital yard signs (Casey 1996). In 1998, candidates made use of their sites to solicit small-dollar contributions however better, particularly by using them.Like it or not, the Internet is now a campaign tool that many campaigns employ. Therefore, we believe the manner in which it is used needs to be investigated. In this article we pay particular attention to candidates' solicitation of campaign contributions over the Internet. Our analysis is mostly descriptive as we try to summarize the Internet activity of candidates in a sample of Senate and House races during 1998.
[3+2] Cycloaddition Approaches to Five-Membered Rings via Trimethylenemethane and Its Equivalents [New Synthetic Methods (55)]

The power of cycloadditions for ring formation derives from the potential for chemo-, regio-, diastereo-, and enantioselectivity. Trimethylenemethane (TMM) and its equivalents offer the possibility of extending such benefits to the synthesis of five-membered rings. Three types of conjunctive reagents appear to be promising candidates: (1) selected 4-alky-lidene-4,5-dihydro-3H-pyrazoles, (2) 2-[(trimethylsilyl)methyl]allyl esters and halides, and (3) alkylidenecyclopropanes. Thermal reactions, especially intramolecular ones, effect the cycloaddition of the pyrazoles to olefins–especially electron-poor olefins. The latter two precursors require a catalyst, notably a palladium complex, to unlock the synthetic potential. With the 2-[(trimethylsilyl)methyl]allyl esters, a general chemo-, regio-, and diastereoselective cycloaddition with typical Diels-Alder dienophiles forms methylenecyclopentanes in both inter- and intramolecular fashion. A tin analogue allows extension of this cycloaddition to aldehydes, and, in a related sequence, to ketones and imines to form 3-methylenete-trahydrofurans and 3-methylenepyrrolidines with excellent diastereoselectivity. The 2-[(tri-methylsilyl)methyl]allyl esters also serve to effect net methylenecyclopentane annulation to cyclic enols. Such adducts can further undergo three-carbon intercalation or combined ring contraction-spiroannulation simply by the use of either a nucleophilic or electrophilic trigger. Alkylidenecyclopropanes undergo cycloadditions to both electron-rich and electron-poor olefins when stimulated by metal catalysts, especially palladium. A complementary regiochemistry to the approach based upon silicon conjunctive reagents is observed. The availability of these cycloadditions provides new strategies for the synthesis of natural products.
Myocardial infarction patients' use of metaphors to share meaning and communicate underlying frames of experience

Myocardial infarction patients' use of metaphors to share meaning and communicate underlying frames of experience¶The onset of a myocardial infarction (MI) is frequently associated with distinct sensations that may shape the personal meaning of the MI illness experience. Although highly important, patients may have difficulty communicating the personal meaning of the MI illness experience because of lack of congruence between the clinician's and patient's frames of experience. The frame of experience defines the context and agenda for encounters from each participant's perspective. This secondary analysis of data explored MI patients' use of metaphorical language to convey aspects of their underlying frame of experience. Specifically, this paper addressed (a) the structural and linguistic features of metaphorical language used by patients to describe MI pain, (b) the content and structure of associated patient metaphors, and (c) the similarities and differences between the content of patient metaphors and descriptions of MI pain. Our findings confirm that even in encounters characterized by clinician imposition of an organizing framework upon the patient encounter, patients use metaphors to reveal their underlying frame of experience and aspects of the personal meaning of the MI illness experience. Furthermore, although non-metaphorical descriptions provide insights into the patients' cognitive understanding of events associated with the MI, metaphorical descriptions are particularly helpful in eliciting aspects of the affective response to the MI.
Age-related changes of calcitonin secretion in females.

Calcitonin secretion was studied in 50 normal females from 20-69 yr of age, with 10 subjects in each decade. Hormone measurements were made by RIA during response to a 10-min infusion of calcium (as the chloride salt) at 3 mg⁄kg BW. There was a progressive decrease of the calcium-stimulated plasma calcitonin with age. Linear regression analysis demonstrated a significant (P < 0.05) negative correlation (r = −0.29) between calcitonin response and age. Postmenopausal females had a significantly (P < 0.01) smaller calcitonin response than premenopausal females. The time of maximum calcitonin response progressively shifted from 10 min in the younger subjects to 20 min in the older subjects. These studies demonstrated that calcitonin secretion decreases with age in females. This decrease may play some role in the pathogenesis of the progressive loss of bone mass which occurs with aging in females
Investigating cultural heterogeneity in San Pedro de Atacama, northern Chile, through biogeochemistry and bioarchaeology

Individuals living in the San Pedro de Atacama oases and the neighboring upper Loa River Valley of northern Chile experienced the collapse of an influential foreign polity, environmental decline, and the appearance of a culturally distinct group during the Late Intermediate Period (ca. AD 1,100-1,400). We investigate cultural heterogeneity at the Loa site of Caspana through analyses of strontium and oxygen isotopes, cranial modification styles, and mortuary behavior, integrating biological aspects of identity, particularly geographic origins, with cultural aspects of identity manifested in body modification and mortuary behavior. We test the hypothesis that the Caspana population (n = 66) represents a migrant group, as supported by archeological and ethnographic evidence, rather than a culturally distinct local group. For Caspana archeological human tooth enamel, mean (87)Sr/(86)Sr = 0.70771 +/- 0.00038 (1sigma, n = 30) and mean delta(18)O(c(V-PDB)) = -3.9 +/- 0.6 per thousand (1sigma, n = 16); these isotopic data suggest that only one individual lived outside the region. Material culture suggests that the individuals buried at Caspana shared some cultural affinity with the San Pedro oases while maintaining distinct cultural traditions. Finally, cranial modification data show high frequencies of head shaping [92.4% (n = 61/65)] and an overwhelming preference for annular modification [75.4% (n = 46/61)], contrasting sharply with practices in the San Pedro area. Based on multiple lines of evidence, we argue that, rather than representing a group of altiplano migrants, the Caspana population existed in the region for some time. However, cranial modification styles and mortuary behavior that are markedly distinct from patterns in surrounding areas raise the possibility of cultural heterogeneity and cultural fissioning.
Speaker localisation using audio-visual synchrony: an empirical study

This paper reviews definitions of audio-visual synchrony and examines their empirical behaviour on test sets up to 200 times larger than used by other authors. The results give new insights into the practical utility of existing synchrony definitions and justify application of audio-visual synchrony techniques to the problem of active speaker localisation in broadcast video. Performance is evaluated using a test set of twelve clips of alternating speakers from the multiple speaker CUAVE corpus. Accuracy of 76% is obtained for the task of identifying the active member of a speaker pair at different points in time, comparable to performance given by two purely video image-based schemes. Accuracy of 65% is obtained on the more challenging task of locating a point within a 100×100 pixel square centered on the active speaker's mouth without no prior face detection; the performance upper bound if perfect face detection were available is 69%. This result is significantly better than two purely video image-based schemes.
Lipid bilayer dynamics from simultaneous analysis of orientation and frequency dependence of deuterium spin-lattice and quadrupolar order relaxation

Simultaneous analysis of the deuterium ${(}^{2}\mathrm{H})$ NMR spin relaxation rates of lipid bilayers as a function of both frequency and sample orientation may be decisive in evaluating different models for the dynamics of membranes. Angular dependent ${}^{2}\mathrm{H}$ spin-lattice ${(R}_{1Z})$ and quadrupolar order ${(R}_{1Q})$ ${}^{2}\mathrm{H}$ relaxation rates have been measured at 46.1 and 76.8 MHz for macroscopically oriented bilayers of 1,2-diperdeuteriomyristoyl-$\mathrm{sn}$-glycero-3-phosphocholine (DMPC-${d}_{54}),$ with perdeuterated acyl chains, in the liquid-crystalline ${(L}_{\ensuremath{\alpha}})$ state. The data have been simultaneously fitted to various dynamical models, together with frequency dependent ${}^{2}\mathrm{H}$ ${R}_{1Z}$ data for vesicles of specifically ${}^{2}\mathrm{H}$-labeled DMPC. The same mechanism for the nuclear spin relaxation in lipids has been assumed for both oriented bilayers and vesicles, except for the presence of orientational averaging and a possible contribution from vesicle tumbling in the latter case. A noncollective model describing individual molecular reorientations in the presence of a potential of mean torque is able to adequately account for the orientation dependence; however, the quality of the fits to the frequency dispersion is less satisfactory. By contrast, a three-dimensional director fluctuation model accounts for the frequency dispersion for DMPC vesicles, but does not fit the orientation dependence of the ${R}_{1Z}$ and ${R}_{1Q}$ relaxation data. Higher-order director fluctuations have also been included, which do not significantly improve the quality of the fits to the collective model. Therefore, a composite membrane model is proposed including both noncollective molecular motions and director fluctuations. The model adequately describes both the frequency and orientation dependent data along the entire acyl chain simultaneously, which suggests that both dynamical processes can be detected by analyzing the ${}^{2}\mathrm{H}$ NMR relaxation rates in the MHz range. Quantitative information about the bilayer dynamics including lipid reorientation rates, degree of molecular ordering, relative contributions from collective and noncollective motions, and director-frame spectral densities of motion has been obtained. The results suggest the bilayer dynamics in the MHz regime reflect molecular reorientations that are superimposed onto nematiclike deformations of the membrane interior in the liquid crystalline state.
A Study of Thoughtful Literacy and the Motivation to Read

This study examined the motivation to read of children in grades two through six. All children in the study were strong in their literal comprehension of narrative text. Some were equally strong in their ability to respond thoughtfully to the text (Blue Group); others struggled to respond to questions requiring them to think about the implications of text (Red Group). The Blue Group was significantly more motivated to read than the Red Group, particularly in the value that they ascribed to reading. Significant differences in favor of Red Group females in the value of reading were not present in the Blue Group. The authors called for teachers to investigate the potential benefits of teaching children to approach reading as thoughtful literacy and to determine if that approach could slow the typical loss of reading motivation in the elementary school years.
The Formation of the Russian National Identity: The Role of Status Insecurity and Ressentiment

This paper is a part of a much larger study in comparative historical sociology addressing the question of the emergence and initial development of the related phenomena that may be subsumed under the umbrella term “nationalism”: national identity, national consciousness, and political collectivities based on such an identity and consciousness—nations. This larger project focuses on the five societies that were among the very first to define themselves as nations—England, the United States of America, France, Germany, and Russia—and examines the social bases of national identity, its embodiment in and perpetuation through institutional arrangements and patterns of culture, and its transformation in the process of diffusion from one culture to another.
Dissemination of a simulation-based mastery learning intervention reduces central line-associated bloodstream infections

Background Approximately 41 000 central line-associated bloodstream infections (CLABSI) occur annually in US hospitals. We previously developed a simulation-based mastery learning (SBML) curriculum in central venous catheter (CVC) insertion that significantly reduced CLABSI rates. In this study, we evaluated the effect of dissemination of the SBML curriculum on trainee skills and CLABSI rates at a community hospital. Methods The authors performed a cohort study of residents who rotated in the intensive care unit (ICU) at Mercy Hospital and Medical Center from September 2010 to May 2012. Residents underwent an SBML CVC insertion curriculum and were required to meet or exceed a minimum passing score on a simulated internal jugular (IJ) and subclavian (SC) CVC insertion before ICU patient care. Infection control personnel measured CLABSI rates in the ICU before and after the educational intervention. Results Residents scored a mean IJ pretest of 35.5% (10.29/29, SD=8.30) compared with a post-test mean of 93.0% (26.96/29, SD=1.50; p<0.001). Their mean SC pretest score was 23.0% (6.68/29; SD=9.58) and increased to 96.1% (27.88/29, SD=1.41) at post-test (p<0.001). Patients experienced 3.82 infections per 1000 catheter-days (20 infections in 5235 catheter-days) in the ICU in the 23 months before the educational intervention. During the 21 months after the intervention, there were 1.29 infections per 1000 catheter-days (six infections in 4670 catheter-days (p=0.019)). The incidence rate ratio derived from the Poisson regression was 0.26 (95% CI 0.09 to 0.74) after controlling for Acute Physiology and Chronic Health Evaluation III score indicating that there was a 74% reduction in the incidence of CLABSI in the medical ICU after the intervention. Conclusions This study demonstrates successful dissemination and implementation of a CVC SBML curriculum and shows that rigorous medical education is a powerful quality improvement tool.
Exact Modeling of Propagation for Permutation-Scanning Worms

Modeling worm propagation has been an important research subject in the Internet-worm research community. An accurate analytical propagation model allows us to study the spreading speed and traffic pattern of a worm under an arbitrary set of worm/network parameters, which is often computationally too intensive for simulations. More importantly, it gives us an insight into the impact of each worm/network parameter on the propagation of the worm and the effectiveness of a potential defense mechanism that is designed to control some of those parameters. Traditionally, most modeling work in the area concentrates on the relatively simple random-scanning worms. However, worm technologies have advanced rapidly in recent years. By enabling close coordination among all infected hosts, the permutation-scanning worms minimize the duplication of effort when scanning the whole Internet address space. They propagate much faster, and more importantly, can be much more stealthy than the random-scanning worms. Modeling these worms, however, remains a challenge to date. This paper proposes a mathematical model that precisely characterizes the propagation patterns of the permutation-scanning worms. The analytical framework captures the interactions among all infected hosts by a series of inter-dependent differential equations, which together present the overall behavior of the worm. We use simulations to verify the numerical results from the model, and demonstrate how the model can be used to study the impact of various worm/network parameters on the propagation.
A global nonhydrostatic semi-Lagrangian atmospheric model without orography

Abstract A global nonhydrostatic semi-implicit semi-Lagrangian (SISL) atmospheric model with orography has been developed. The height-based terrain-following σz coordinate of Gal-Chen and Somerville is used to incorporate the orography. A 3D vector form of the SISL formulation is proposed. It is based on the complete Navier–Stokes equations. The model is stable for large time steps of up to 1 h at horizontal/vertical resolution of 2.8125°/1200 m. Isolated bell-shaped mountain profiles and real orography are employed to evaluate the model performance. The sensitivity of the model with orography to the order of accuracy of the uncentering scheme, the reference temperature (T), and size of the time step are similar to that of the model without orography described in Semazzi et al. The authors find that for successful execution of the model, it is important that the orographic height Zs, the reference state mass variable (qs), and T satisfy the hydrostatic balance relationship in the terrain-following σz coor...
Mycobacterium kansasii causing chronic monoarticular synovitis in a patient with HIV/AIDS

Mycobacterium kansasii is a nontuberculous mycobacterium that primarily causes pulmonary disease in AIDS patients, however it has also been known, rarely, to result in skeletal infection. When skeletal infection occurs, the time from onset of symptoms to diagnosis is up to 5 years in previously reported cases. We describe a 48-year-old woman with HIV/AIDS who presented with chronic, isolated left knee pain and swelling of over two decades which had recently worsened. Radiographs and magnetic resonance imaging demonstrated marked subarticular erosions, synovial thickening, and bone marrow edema, which had progressed compared with prior imaging done seven years earlier. Synovial biopsy grew Mycobacterium kansasii. Following the presentation of our case, clinical and imaging findings, including the differential diagnosis, of monoarticular arthritis caused by Mycobacterium kansasii are reviewed and discussed.
Web Access To National Health Survey Text/Image Databases

In this chapter we discuss the problem of providing access to databases created from two health surveys of the U.S. population which contain demographic, socioeconomic, and health history information derived from questionnaires, as well as hundreds of health-related measurements derived from physical examination and laboratory measurement. Included in this data are 17,000 digitized radiographs of the cervical and lumbar spine; an additional 10,000 digitized hand and knee radiographs are expected to be added. We discuss issues in using the Java language as a basic tool for system development, including comparing Java to HTML/CGI, getting access to resources local to the client machine, class download time, and access time for large image files. We describe the Web-based Medical Information Retrieval System (WebMIRS), a Java applet we have created which provides SQL query capability to these databases with display of the resulting text and image records, and which will have research capability to query the databases by image content, in combination with standard text queries.
Co-morbidity in adults with ADHD.

Attention-deficit/hyperactivity disorder (ADHD) is highly co-morbid across the life span. However, co-morbidity is not uniform across time; individual co-morbid conditions tend to occur at different times developmentally, with rates often reflecting lifetime occurrence (Slide 1). In addition to changes in the rates of co-morbidity, the nature of co-morbidity may also differ in late adolescence/adulthood, when co-morbid conditions can be especially impairing (eg, antisocial disorder, substance use disorder [SUD], more severe mood disorders).
Staying District Court Proceedings Pending FAA § 16(A) Appeals

Section 16(a) of the Federal Arbitration Act allows an immediate appeal from orders denying arbitration. When an order denies arbitration and the party demanding arbitration appeals, the statute does not specify whether a district court must stay litigation pending that appeal. Both the federal circuits and the student notes written on the topic to date are split on the issue. This article analyzes the four factors courts have used in cases raising this issue. Unlike the cases and notes on point to date, this article also analyzes the issue in light of the Supreme Court’s 2009 decision of Arthur Andersen LLP v. Carlisle which, though not directly on point, provides significant guidance regarding the direction the Supreme Court is likely to go. This article argues that courts should adopt the automatic stay approach because it is most consistent with the text and purpose of the FAA, it follows the reasoning of Supreme Court precedent, it best addresses the policy concerns of preventing frivolous appeals, and it is most consistent with the intent of signatories to arbitration agreements.
More than an adaptor molecule: The emerging role of tRNA in cell signaling and disease

This FEBS Letters “FOCUS ON…” series of short reviews on tRNA captures the essence of the Barcelona BioMed Conference on Gene Translation: Fidelity and Quality Control, which was held at the Institut d'Estudis Catalans in Barcelona on December 2–4, 2013. This meeting was powered by the dramatic resurgence of interest in tRNA biochemistry following the realization that tRNA is much more than a simple adaptor of the genetic code. This realization stems in part from the emergence of new convergent technologies, such as deep sequencing, bioinformatics, biological mass spectrometry and ‘omic science, as well as from the growing body of evidence that connects translation biology to the cell cycle, metabolism and disease. Research on translation has long focused on the interactions between the basic players of translation (tRNA, aminoacyl-tRNA synthetases, transcripts and ribosomes), but these interactions were mainly studied in isolation from the rest of the cell. However, tRNAs have now emerged as key players in the many mechanisms of control that tightly couple protein synthesis to the main signaling pathways that modulate cell biology and pathophysiology. Recent discoveries on the connections between tRNAs and signaling pathways and cell function have highlighted the need to establish a fluid dialogue among laboratories that approach the problem from its many different perspectives. The Barcelona BioMed Conference recognized and consolidated these emerging ideas and discoveries, the scientific substance of which is reflected in the five mini-reviews of this “FOCUS ON…” series. A major focus was the growing area of tRNA mistranslation (see also Moghal et al.), from the perspective of pathological errors in protein sequences due to mischarging of tRNAs, to the concept of “adaptive mistranslation” as a stress response and survival mechanism for many organisms. Another emerging topic was the role of anticodon modifications and their effects upon codon usage patterns and codon-biased translation in cell stress responses and pathophysiology (Begley and Dedon). A third area of interest was discoveries of direct mechanistic links between human diseases, such as cancer and neurodegeneration, and facets of tRNA biology including tRNA modification and maturation (Torres et al.), tRNA cleavage (Anderson and Ivanov) and aminoacyl-tRNA synthetases (Laporte et al.). While the meeting successfully accomplished the objective of bringing together a diverse group of scientists to discuss the present and the future of tRNA research, this FOCUS ON…series reflects its scientific substance, as well as the excitement still resonating among those who attended the conference. As co-organizers of this meeting and editors of the FOCUS ON…, we hope that you might share the excitement about these new developments in tRNA biology.
Dislocation Generation and Crack Propagation in Metals Examined in Molecular Dynamics Simulations

We have carried out a series of atomistic simulations on arrays of about 10,000 atoms containing an atomically sharp crack and subjected to increasing stress levels. The ordered stoichiometric alloys B2 NiAl, B2 RuAl and A15 Nb3AI have been studied at different temperatures and stress levels, as well as the elements Al, Ni, Nb and Ru. The many body interactions used in the simulations were derived semi-empirically, using techniques related to the Embedded Atom Method. Trends in dislocation generation rates and crack propagation modes will be discussed and compared to experimental indications where possible, and some of the simulations will be demonstrated in the form of computer movies.