cssi/SciSciGPT-SciSciNet huggingface dataset:
Damage-Associated Molecular Patterns Induce Inflammatory Injury During Machine Preservation of the Liver: Potential Targets to Enhance a Promising Technology.

Machine preservation (MP) has emerged as a promising technology in liver transplantation, but the cellular processes occurring during MP have not been characterized. Recent studies have noted the presence of inflammatory molecules generated during MP. We hypothesized that there is a metabolism-dependent accumulation of damage-associated molecular patterns (DAMPs) and inflammatory cytokines during MP and that these molecules provoke inflammation in the graft. To stratify groups by metabolic rate, MP was performed on rat livers from standard donors at 3 different temperatures: room temperature (RT), subnormothermic (30°C), and normothermic (37°C). Static cold storage at 4°C was included as a reference group. Following a 4-hour preservation period, graft reperfusion was performed ex vivo at 37°C (n = 6 for all groups). Levels of DAMPs and inflammatory cytokines were measured, and their biological activity was assessed by determining toll-like receptor (TLR) stimulation, inflammatory gene expression, and activation of cell death pathways. There was a time-dependent increase in levels of DAMPs during MP with high-mobility group box 1 and extracellular DNA levels increasing for all groups (P < 0.05, 30 versus 240 minutes). Tumor necrosis factor α levels in the perfusate also increased during MP for all groups (P < 0.05, 30 minutes versus 240 minutes). Levels of inflammatory molecules correlated with increased activation of TLRs (TLR3, P = 0.02, normothermic machine preservation [MP37] versus machine preservation at room temperature [MPRT]; TLR9, P = 0.02, MP37 versus MPRT). Priming of the NLRP3 inflammasome and activation of cell death pathways were reduced in grafts preserved by MP at room temperature. In conclusion, inflammatory molecules produced during MP have a biological impact on the graft. Therapies to attenuate DAMP-mediated inflammation during MP may further enhance this promising technology.
Overuse and Limited Benefit of Chemotherapy for Stage II Colon Cancer in Young Patients.

Abstract Background Few studies have confirmed a benefit for adjuvant chemotherapy (aCTX) in stage II colon cancer. We used the National Cancer Database to explore the use and efficacy of aCTX in patients with both normal-risk (NR) and high-risk (HR) young stage II colon cancer. Patients and Methods We identified patients with stage II colon cancer who underwent colectomy between 2010 and 2015. HR patients included at least: lymphovascular or perineural invasion, Results Among the 81,066 stage II patients who underwent colectomy, 6093 (7.5%) were 50 years (P Conclusion Young patients with HR and NR colon cancer received aCXT more frequently than older patients with no demonstrable survival benefit. This bears further evaluation to avoid the real risks of over-treatment in this increasing population.
Graphene prevents neurostimulation-induced platinum dissolution in fractal microelectrodes

Platinum (Pt) is one of the most commonly used materials for neural interface owing to its excellent biocompatibility and good charge transfer characteristics. Although Pt is generally regarded to be a safe and inert material, it is known to undergo irreversible electrochemical dissolution during neurostimulation. The byproducts of these irreversible electrochemical reactions are known to be cytotoxic that can damage the surrounding neural substrate. With decreasing size of microelectrodes for more advanced high-density neural interfaces, there is a need for a more reliable, safe, and high-performance neurostimulating electrodes. In this work, we demonstrate that a monolayer of graphene can significantly suppress Pt dissolution while maintaining excellent electrochemical functionality. We microfabricated bare and graphene-coated Pt microelectrodes with circular and fractal designs and measured their Pt dissolution rate using inductively coupled plasma mass spectrometry. In addition, we measured changes in electrochemical characteristics of these microelectrodes before and after a prolonged stimulation period to quantify the effects of Pt dissolution and graphene protective layer. We confirm that fractal microelectrodes do have a better charge transfer performance than conventional circular designs but bare Pt fractal microelectrodes had significantly faster dissolution rate than the circular ones. When coated with monolayer of graphene, however, Pt dissolution was reduced >97% for fractal microelectrodes while they retained the superior charge transfer characteristics. The results of our work suggest that graphene can serve as an excellent diffusion barrier that can ameliorate the concerns for Pt dissolution in chronically implanted neurostimulation microelectrodes.
Contact Center Operations Management Systems Architecture and Reliability

Contact centers play a critical role in service businesses by acting as the interface between customers and the organizations. They are strategic tools to establish a relationship with customers to promote customers satisfaction, which can lead to an increase in customer loyalty and sales. One important factor impacting customer satisfaction is the service quality, which should be constantly monitored and aligned with the organization strategic management. This paper investigates contact centers from a systems perspective to help decision-makers have a holistic view of customer support process. We present an architecture of the contact center operations management system incorporating concepts of enterprise transformation, and describe its components and functions. As reliability is one of the most important dimensions of service quality, we propose a mathematical model to measure the reliability of the system. The developed system architecture and reliability metric are general enough and can be implemented in any industry. An empirical analysis using data from a major insurance company is provided to illustrate the applicability of the system design, reliability, and performance control using a control chart.
A student affairs podcast as novel communication tool

Podcasts are prevalent within medical education, but not within medical student affairs. Our Office of Student Affairs (OSA) created a podcast focusing on topics relevant to the medical student experience. There have been over 20,000 downloads thus far. Survey responses and feedback have been positive and highlight the podcast’s utility as a communication tool, with 96% of respondents saying they would recommend this podcast to others. Given the mission of student affairs offices to advise, mentor, and educate students, a student affairs podcast is an exciting innovation for medical schools to consider.
Zinc Gluconate Induces Potentially Cancer Chemopreventive Activity in Barrett's Esophagus: A Phase 1 Pilot Study.

Chemopreventive effects of zinc for esophageal cancer have been well documented in animal models. This prospective study explores if a similar, potentially chemopreventive action can be seen in Barrett’s esophagus (BE) in humans. To determine if molecular evidence can be obtained potentially indicating zinc’s chemopreventive action in Barrett’s metaplasia. Patients with a prior BE diagnosis were placed on oral zinc gluconate (14 days of 26.4 mg zinc BID) or a sodium gluconate placebo, prior to their surveillance endoscopy procedure. Biopsies of Barrett’s mucosa were then obtained for miRNA and mRNA microarrays, or protein analyses. Zinc-induced mRNA changes were observed for a large number of transcripts. These included downregulation of transcripts encoding proinflammatory proteins (IL32, IL1β, IL15, IL7R, IL2R, IL15R, IL3R), upregulation of anti-inflammatory mediators (IL1RA), downregulation of transcripts mediating epithelial-to-mesenchymal transition (EMT) (LIF, MYB, LYN, MTA1, SRC, SNAIL1, and TWIST1), and upregulation of transcripts that oppose EMT (BMP7, MTSS1, TRIB3, GRHL1). miRNA arrays showed significant upregulation of seven miRs with tumor suppressor activity (-125b-5P, -132-3P, -548z, -551a, -504, -518, and -34a-5P). Of proteins analyzed by Western blot, increased expression of the pro-apoptotic protein, BAX, and the tight junctional protein, CLAUDIN-7, along with decreased expression of BCL-2 and VEGF-R2 were noteworthy. When these mRNA, miRNA, and protein molecular data are considered collectively, a cancer chemopreventive action by zinc in Barrett’s metaplasia may be possible for this precancerous esophageal tissue. These results and the extensive prior animal model studies argue for a future prospective clinical trial for this safe, easily-administered, and inexpensive micronutrient, that could determine if a chemopreventive action truly exists.
Woody Cover Mediates Fox and Gray Squirrel Interactions

Human activities are changing the environments that animal communities utilize, altering competition and co-existence dynamics as well as changing species distributions. A global consequence of human activity is increased woody cover, which changes environmental conditions on landscape, local, and fine spatial scales. These multi-scale processes are likely to change species interactions and distributions in unexpected ways. To elucidate these effects, we investigated the co-occurrence of two interacting species in a rapidly changing ecosystem. Eastern fox (Sciurus niger) and gray (S. carolinensis) squirrels occur sympatrically throughout the southeastern United States. We used single-season, two-species occupancy modeling to understand what factors influence competition between the squirrels at three spatial scales. We found evidence that fox and gray squirrels compete at fine scales but not at local and landscape scales. The best model to explain fox and gray squirrel co-occurrence at fine scales was an additive fine scale understory and tree canopy closure model. Increased fine-scale canopy closure correlated with increased fox and gray squirrel occupancy while increased fine-scale understory cover correlated with decreased gray and fox squirrel occupancy. Fox squirrel occupancy probability declined in the presence of gray squirrels. The intensity of interaction was modified by fine-scale canopy cover and understory density. These findings support the hypothesis that species interactions can be an important factor in structuring biotic communities, however the strength of the effect changes across spatial scales. Our results support the importance of considering species interactions at multiple scales when predicting community composition in human modified and managed systems.
Factors Associated With the Professional Success of Female Surgical Department Chairs: A Qualitative Study

Importance Only 7% of US surgical department chairs are occupied by women. While the proportion of women in the surgical workforce continues to increase, women remain significantly underrepresented across leadership roles within surgery. Objective To identify commonality among female surgical chairs with attention toward moderators that appear to have contributed to their professional success. Design, Setting, and Participants A grounded theory qualitative study was conducted in academic surgical departments within the US. Participants included current and emeritus female chairs of American academic surgical departments. The study was conducted between December 1, 2018, and March 31, 2019. An eligible cohort of 26 women was identified. Interventions and Exposures Participants completed semistructured telephone interviews conducted with an interview guide. Main Outcomes and Measures Common themes associated with career success. Results Of the eligible cohort of 26 women, 20 individuals (77%) participated. Sixteen participants were serving as active department chairs and 4 were former department chairs. Mean (SD) length of time served in the chair position, either active or former, was calculated at 5.6 (2.6) years. Two major themes were identified. First, internal factors emerged prominently. Personality traits, including confidence, resilience, and selflessness, were shared among participants. Adaptability was described as a major facilitator to career success. Second, participants described 2 subtypes of external factors, overt and subtle, each of which included barriers and bolsters to career development. Overt support from mentors of both sexes was described as contributing to success. Subtle factors, such as gender norms, on institutional and cultural levels, affected behavior by creating environments that supported or detracted from career advancement. Conclusions and Relevance In this study, participants described both internal and external factors that have been associated with their advancement into leadership roles. Future attention toward encouraging intrinsic strengths, fostering environments that bolster career development, and emphasizing adaptability, along with work-system redesign, may be key components to career success and advancing diversity in surgical leadership roles.
Applying OSiRIS NMAL to Network Slices on SLATE

The Network Management Abstraction Layer (NMAL) extends perfSONAR capabilities to include automated network topology discovery and tracking in the Unified Network Information Service (UNIS), and incorporate Software Defined Networking (SDN) into overall operations of the OSiRIS distributed Ceph infrastructure. We deploy perfSONAR components both within OSiRIS and at our “client” locations to allow monitoring and measuring the networks interconnecting science domain users and OSiRIS components. Topology discovery (using an SDN controller application) and Flange Network Orchestration (NOS) rules are used to dynamically manage network pathing in our testbed environments. NMAL components have been containerized to operate within the Services Layer at the Edge (SLATE) infrastructure, and we describe our experiences in packaging and deploying our services.
Lamellar Level Correlations Between Mechanical Behavior and Composition in Mouse Bone

We studied the lamellar level correlations between the local composition and local mechanical properties in the femur of two inbred strains of mice (A/J and C57BL/6J (B6)), with known differences in the average mineralization and long-bone mechanical properties, to gain insights into how their extracellular matrix is mineralized. The local elastic moduli and indentation yield strengths were determined using spherical nanoindentation stress-strain analysis, while Raman spectroscopy was used to determine the local composition around the indents in a total of 11 samples. Our results show a significant difference in the mineral-to-matrix ratio of the two strains of mice, with the A/J mice showing an overall higher mineral-to-matrix ratio and lower carbonate substitution in the mineral. These differences are prominent in the newer bone and become less significant as the bone matures. Additionally, local mineral-to-matrix ratio was found to be a good indicator of the local mechanical properties.
Bayesian Methodology for Uncertainty Quantification in Complex Engineering Systems

This chapter presents a Bayesian methodology for system-level uncertainty quantification and test resource allocation in complex engineering systems. The various component, subsystem, and system-level models, the corresponding parameters, and the model errors are connected efficiently using a Bayesian network. This provides a unified framework for uncertainty analysis where test data can be integrated along with computational models across the entire hierarchy of the overall engineering system. The Bayesian network is useful in two ways: (1) in a forward problem where the various sources of uncertainty are propagated through multiple levels of modeling to predict the overall uncertainty in the system-level response; and (2) in an inverse problem where the model parameters of multiple subsystems are calibrated simultaneously using test data. Test data available at multiple data are first used to infer model parameters, and then, this information is propagated through the Bayesian network to compute the overall uncertainty in the system-level prediction. Then, the Bayesian network is used for test resource allocation where an optimization-based procedure is used to identify tests that can effectively reduce the overall uncertainty in the system-level prediction. Finally, the overall Bayesian methodology for uncertainty quantification and test resource allocation is illustrated using three different numerical examples. While the first example is mathematical, the second and third examples deal with practical applications in the domain of structural mechanics.
Electronic Oscillators with Bias-Shift Limiting

In this chapter a major, yet simple oscillator prototype is studied, together with several derivative configurations. Of particular interest is the fact that although the basic differential equation which describes the oscillator has the same form as that encountered in the last chapter, there is now a new limiting phenomenon. The essential limiting of the growth of oscillatory buildup is due to the shift of the virtual or dynamic operating point of the configuration. That is, the effective bias point of the oscillator shifts from the initial values at the quiescent state in the active region of the device(s) to equivalent bias values corresponding to a near-off state of the devices. Steady-state operation of the oscillator corresponds to Class-C operation wherein the devices are off during more than one-half of the period of the oscillation.
The Performance Of Nonlinearity Tests On Asymmetric Nonlinear Time Series

Abstract This paper examines nonlinearity tests of asymmetric time series in a controlled Monte Carlo setting with the goal of exploring how well existing nonlinear test statistics performed in a variety of typical time series settings. The data generation processes and sample sizes were allowed to vary in a controlled fashion. The study confirmed that none of the test statistics were dominant relative to the others. Also, dependent upon the data generating process, the test statistics exhibited very different powers. Finally, our research showed that the test performance was heavily dependent upon sample size and the degree of asymmetric mechanism.
Ligation of Cell Surface-Associated Glucose-Regulated Protein 78 by Receptor-Recognized Forms of α2-Macroglobulin: Activation of p21-Activated Protein Kinase-2-Dependent Signaling in Murine Peritoneal Macrophages

Previous studies of the plasma proteinase inhibitor α 2 -macroglobulin (α 2 M) demonstrated that α 2 M-proteinase complexes (α 2 M*) modulate immune responses and promotes macrophage locomotion and chemotaxis. α 2 M* binds to cell surface-associated glucose-regulated protein 78 (GRP78), which activates downstream signaling events. The role of p21-activated protein kinase-1 and -2 (PAK-1 and -2) in promoting cellular motility is well documented. In the current study, we examined the ability of α 2 M* to activate PAK-1 and PAK-2. Upon macrophage stimulation with α 2 M*, PAK-2 is autophosphorylated, resulting in increased kinase activity; however, PAK-1 is negligibly affected. α 2 M*-stimulated macrophages showed a marked elevation in the levels of Rac·GTP. Receptor tyrosine phosphorylation upon binding of α 2 M* to GRP78, recruits PAK-2 to the plasma membrane via the adaptor protein NCK. Consistent with this hypothesis, silencing of GRP78 gene expression greatly attenuated the levels of membrane-associated PAK-2 and NCK. PAK-2 activity was markedly decreased by inhibition of tyrosine kinases and PI3K before α 2 M* stimulation. We further demonstrate that phosphorylation of Lin-11, Isl-1, Mec-3 (LIM) kinase and cofilin is promoted by treating macrophages with α 2 M*. Thus, α 2 M* regulates activation of the PAK-2-dependent motility mechanism in these cells.
Anomalous momentum dependence of the quasiparticle scattering rate in overdoped Bi2Sr2CaCu2O8.

The momentum dependence of the ‘‘quasiparticle’’ width along the Fermi surface is a very sensitive test of the scattering processes in cuprates, which is ultimately important to understand its superconducting mechanism. In the underdoped regime in p-type cuprates [1– 4], it has been shown in many systems that the spectra near �; 0 is particularly broad. This anisotropy is generally attributed to spin scattering centered at Q �; � , that for p-type cuprates in the k space connects �; 0 to 0 ;� points of the Brillouin zone —the Fermi surface ‘‘hot spots.’’ In optimal and overdoped n-type materials, the Q �; � vector also connects Fermi surface points, and corresponding hot spots were recently reported in Nd1:85Ce0:15CuO4 (NCCO) [5]. The Q �; � scattering and its broadening of the �; 0 spectra exhibit itself most strongly in the undoped insulator [6,7]. There is a general agreement that insulating behavior in the undoped system results from a strong electron-electron correlation effect which is also intimately related to antiferromagnetic interactions peaked at Q �; � . Hence, an anisotropy in peak width which increases towards �; 0 in p-type materials is a hallmark of the impact on the electron dynamics by Q �; � antiferromagnetic interaction. Since this effect is generally expected on theoretical grounds and is seen in many materials, it remains true despite two technical problems complicating the analysis of the Bi2212 data near �; 0. One is the superstructure, and the other is the recently realized bilayer splitting [8– 11] that strongly influences the near �; 0 spectra when it is unresolved. The scattering anisotropy in overdoped p-type samples has hardly been studied, other than a brief discussion of Bi2212 in [1], and the resolution was not good enough for quantitative analysis. In this Letter, we present the first results of scattering rate measurements along the two well-resolved pieces of the Fermi surface in overdoped Pb-doped Bi2212 with suppressed superstructure. As shown in Fig. 1, these samples and experimental setup allow clear observation of the two bilayer-split Fermi surfaces using angle-resolved photoemission spectroscopy (ARPES) [10]. We performed measurements above and well below the superconducting transition temperature to measure the widths of the quasiparticle peaks along the two resolved Fermi surface pieces and found that the scattering rate does not increase towards �; 0. This contradicts what is expected from Q �; � scattering, indicating that the hot spot has already turned cold at this doping level. This strongly suggests that any magnetic excitations near Q �; � would have minimal effect on the quasiparticle dynamics, consistent with [12,13], but inconsistent with [14 –17]. This finding in a sample with Tc as high as 70 K puts a very strong constraint on theory. In particular, it shows that the Q �; � magnetic resonance mode cannot be the driving force for pairing.
Determination of platinum and rhodium in γ-alumina catalysts by glow discharge atomization atomic absorption spectrophotometry

Abstract The technique of glow discharge atomization atomic absorption spectrophotometry (GDA-AAS) is used to determine platinum and rhodium concentrations in automotive catalyst materials. The glow discharge atomizer allows these difficult-to-dissolve samples to be atomized directly from the solid state after the alumina-based catalyst is mixed intimately with a conductive host matrix material. A troublesome and time-consuming dissolution step is therefore unnecessary. Optimization of the major analytical parameters (discharge current, discharge pressure, and the percentage of catalyst to be mixed with host material) is presented, along with actual determinations of platinum and rhodium, via calibration curves. Internal standardization is employed to compensate for differences in sputtering efficiency from sample to sample. Relative sensitivity factors (RSF) are also used for quantitation. The technique is shown to provide accurate determinations with relative errors of 2–3% ( C x / C known × 100%) with either quantitation scheme, providing a relatively rapid and inexpensive alternative to competing methods of analysis.
Recent developments in factor-facilitated ribosome assembly.

Abstract Escherichia coli ribosomal subunits can be reconstituted in vitro under highly optimized conditions. These reconstitution systems have proven invaluable for the study of ribosomal subunit assembly. While E. coli ribosomal subunits can self-assemble in vitro there has been much speculation regarding the existence of extra-ribosomal assembly factors that act in functional subunit formation in vivo. Recently, a biochemical assay has been implemented to identify factors that facilitate a single, critical step in 30S subunit assembly in vitro. These studies have revealed that the DnaK (heat shock protein 70) chaperone system can facilitate 30S subunit assembly in vitro. The 30S subunits, formed in the presence of the chaperones under otherwise non-permissive conditions, are highly similar to 30S subunits formed under standard reconstitution conditions. It has become evident that the manner in which the “factor-assembled” 30S subunits are purified is critical for monitoring formation of functional ribosomal particles. Given that methodologies for in vitro reconstitution and functional analysis of ribosomal subunits have been described in detail previously, this manuscript will focus on isolation of functional 30S subunits that have been assembled in the presence of exogenous factors in vitro. Also, recent efforts toward understanding the roles of exogenous factors in 50S subunit and eukaryotic ribosome assembly will be briefly discussed.
Representative instances and γ-acyclic relational schemes

In this paper, we study under what conditions will a pairwise inconsistent relational database ≪R,r≫ have a universal/representative instance L. If R is γ-acyclic and r satisfies all existence constraints, then it is possible to construct a universal instance L, using unmarked nulls, whose total projections onto R yield exactly the relations in r. We show that L would actually be a representative instance under a set of functional dependencies if R satisfies the additional mild condition: for any functional dependency X → A where A is a single attribute, whenever XA is contained in two relation schemes R and R' of R, it follows that R ∩R' is a relation scheme of R, having X as one of its keys.
Investigation of the domain wall fermion approach to chiral gauge theories on the lattice.

We investigate a recent proposal to construct chiral gauge theories on the lattice using domain wall fermions. We restrict ourselves to the finite volume case, in which two domain walls are present, with modes of opposite chirality on each of them. We couple the chiral fermions on only one of the domain walls to a gauge field. In order to preserve gauge invariance, we have to add a scalar field, which gives rise to additional light mirror fermion and scalar modes. We argue that in an anomaly-free model these extra modes would decouple if our model possesses a so-called strong coupling symmetric phase. However, our numerical results indicate that such a phase most probably does not exist.
Women in politics in the people's republic of china: Holding up half the sky?

In China, there has been a long tradition of oppression, with the burden falling particularly on rural women. Since 1949, Chinese leaders have supported women's emancipation as a natural consequence of Socialist economic development. Government actions to mitigate the problem of inequality have enhanced some achievements but are largely inadequate. This paper examines the issue of Chinese women in politics and concludes that negative influences of the past, misunderstanding of the connection between general and gender specific policies, and the absence of general commitment to the ideology of sex equality have been the obstacles to women's emancipation in China.
The Use of Apps to Prime Learning for a Verbal Task

This study tested whether or not children’s memory performance would be affected by stimulating brain activity by completing a verbal puzzle task or a non-verbal puzzle task prior to a verbal learning task.
Properties of multilevel block α̲-circulants

Abstract In a previous paper we characterized unilevel block α -circulants A = [ A s - α r ] r , s = 0 n - 1 , A m ∈ C d 1 × d 2 , 0 ⩽ m ⩽ n - 1 , in terms of the discrete Fourier transform F A = { F 0 , F 1 , … , F n - 1 } of A = { A 0 , A 1 … , A n - 1 } , defined by F l = 1 n ∑ m = 0 n - 1 e - 2 π i l m / n A m . We showed that most theoretical and computational problems concerning A can be conveniently studied in terms of corresponding problems concerning the Fourier coefficients F 0 , F 1 , … , F n - 1 individually. In this paper we show that analogous results hold for ( k + 1 ) -level matrices, where the first k levels have block circulant structure and the entries at the ( k + 1 ) -st level are unstructured rectangular matrices.
Decompositions of vector spaces over GF(2) into disjoint equidimensional affine spaces

We investigate the possibilities for decomposing the vector space [GF(2)]n into a set of 2r−d (necessarily disjoint) d dimensional affine subspaces.
Filament winding cylinders. III: Selection of the process variables

By using the Lee-Springer filament winding model temperatures, degrees of cure, viscosities, stresses, strains, fiber tensions, fiber motions, and void diameters were calculated in graphite-epoxy composite cylinders during the winding and subsequent curing. The results demonstrate the type of information which can be generated by the model. It is shown, in reference to these results, how the model, and the corresponding WINDTHICK code, can be used to select the appropriate process variables.
Characterization of lead zirconate titanate microwires using digital image correlation

Lead zirconate titanate (PZT) microwires with applications in sensors, actuators, and energy harvesters are produced using hydrothermal synthesis. The synthesized microwires are relatively large with an average length of about 450 microns and an average width of 4 microns. Each of these individual PZT microwires can be integrated in smart systems as an active phase or be used as an independent smart material. In this paper, the synthesis procedure and characterization of these large microwires is demonstrated. The converse piezoelectric properties of the microwires are measured using digital image correlation after clamping and adding electrodes at each end of the microwire. It has been shown in the literature that digital image correlation can be used as a precise tool for rapid characterization of piezoelectric materials. Here, it is demonstrated that this technique can be applied to characterize the actual response of piezoelectric materials at the micron scale.
Perturbed angular correlation experiment for 57Fe in a Ni host

Abstract The 122-14 keV gamma-gamma cascade of 57 Fe has been used to detect the precession of the 14 keV state in the hyperfine field of a Ni host. The data yield a hyperfine field of −267.5 ± 2.7 kG at room temperature.
Memory Contrivances in Everyday Life

Phenomena of human memory traditionally have been explained in terms of memory processes. However, memory performance and the claims that people make about memory performance may also reflect social processes such as contriving to make a memory act appear different from what actually occurred The present research investigated the extent of the use of memory contrivances as reported on a questionnaire, Memory Use in Social Environments (MUSE). Factor analysis of the responses of the 92 subjects to the MUSE items identified the following eight forms of contrivances (listed in order from most to least used): ignoring another's remembering, excuses, self-deprecation self-enhancement, cover-ups for self-forgetfulness, politeness, insults and misevaluation. In a second study, 43 subjects identified the social goals underlying the eight contrivances. These results indicate a role for social processes in memory performance not recognized previously; the results also suggest specific ways in which cognitive perfor...
Evaluation of Propofol as a General Anesthetic for Horses

This study provides baseline information on the potential use of propofol as a general anesthetic for horses. Using a Latin square design, propofol (2, 4, and 8 mg/kg) was administered intravenously on three separate occasions to six mature horses. Information about anesthetic induction, duration, and recovery was recorded along with results of rectal temperature, heart rate, respiratory rate, pHa, PaCO2 and PaO2. Statistical analysis included a mixed model analysis of variance, a general linear model analysis and least square means test for post hoc comparisons. A P < .05 was considered significant. The quality of induction of anesthesia varied from poor to good. Two horses were not recumbent following the lowest dose of propofol. Brief paddling limb movements occurred occasionally and unpredictably after recumbency induced by all three doses. During recovery, horses were uniformly calm and coordinated in their moves to stand. Duration of recumbency (minutes) was dose related; 15.05 +/- 1.58 (mean +/- SD) following 2 mg/kg, 31.06 +/- 5.56 following 4 mg/kg, and 47.85 +/- 13.63 following 8 mg/kg. During recumbency at all doses, heart rate significantly increased from a predrug value of 40 +/- 6 beats per minute. Substantial respiratory depression, characterized by a significant decrease in respiratory rate (from 11.7 +/- 2.9 to 3.7 +/- 1.6 breaths per minute) and increased PaCO2 (from 44.5 +/- 2.5 to 52.7 +/- 8.0 mm Hg) was seen only after 8 mg/kg. A significant decrease in PaO2 was observed throughout the recumbency induced by 8 mg/kg, and also at 3 and 5 minutes following induction of anesthesia with 4 mg/kg propofol.(ABSTRACT TRUNCATED AT 250 WORDS)
Advanced flow-through external pressure-balanced reference electrode for potentiometric and pH studies in high temperature aqueous solutions

Abstract A new flow-through external pressure-balanced reference electrode (FTEPBRE) has been developed for potentiometric and pH measurements in high temperature aqueous solutions. The unique feature of this advanced FTEPBRE is that the reference solution flows through the electrode so that the concentration of solution across the thermal liquid junction is well defined. Because the electrolyte concentration profile in the reference electrode is maintained constant, uncertainty in the thermal liquid junction potential (TLJP) can be eliminated at a given temperature and pressure. We have employed the silver⊢silver chloride |platinum|hydrogen non-isothermal electrochemical system for potentiometric measurements of potentials between HCI (aq) solutions of 0.01 and 0.001 mol kg −1 at temperatures up to 633 K and at pressures of 275 and 338 bar. The results of the measurements have been compared with calculations made using the available thermodynamic data, and good agreement, within ±3 to 10 mV, between the calculated and the measured potentials is obtained. We concluded that the advanced reference electrode can be used to make accurate potentiometric measurements (within a few mV) in aqueous systems over wide ranges of temperatures and pressures. Also we demonstrated an ability of the thermocell to measure pH with high accuracy of ± 0.04 to 0.09 over wide ranges of temperature and pressure.
Vasopressin stimulates phospholipase D activity against phosphatidylcholine in vascular smooth muscle cells.

It is now clear that various hormones and agonists can stimulate the production of lipid mediators from nonphosphoinositide phospholipids. We have investigated the production of diacylglycerol from nonphosphoinositide sources, and we demonstrated that vasopressin and other vasoactive agents stimulate hydrolysis of phosphatidylcholine in a variety of cultured vascular smooth muscle cells of rat and human origin. We used vasopressin to characterize this response and found that vasopressin stimulates phospholipase D activity against phosphatidylcholine in A-10 vascular smooth muscle cells. The vasopressin-stimulated phosphatidylcholine hydrolysis is both time- and concentration-dependent. The half-maximal dose of vasopressin required for phosphatidylcholine hydrolysis (ED50∼1 nM) correlates well with vasopressin binding to A-10 cells (Kd∼2 nM). The phosphatidylcholine in A-10 cells can be preferentially radiolabeled with [3H]myristic acid; subsequent treatment with vasopressin stimulates a rapid increase in3H-labeled phosphatidate (∼4×control values at 3 min), and after a short lag,3H-labeled diacylglycerol rises and reaches maximal levels at 10 min (∼2×control values). Similar temporal elevations of phosphatidate and diacylglycerol occur in A-10 cells labeled with [3H]glycerol. In A-10 cells radiolabeled with [3H]choline the elevation of cellular phosphatidate and diacylglycerol is concomitant with the release of [3H]choline metabolites (predominately choline) to the culture medium. The temporal production of phosphatidate and diacylglycerol as well as the release of choline to the culture medium are consistent with vasopressin activating phospholipase D. In addition, vasopressin stimulates a transphosphatidylation reaction that is characteristic of phospholipase D. The transphosphatidylation reaction is detected by the production of phosphatidylethanol that occurs when A-10 cells are incubated with ethanol and stimulated with vasopressin. The phospholipase D is active in the absence of extracellular Ca++ whereas the vasopressin-stimulated mobilization of arachidonic acid is dependent on extracellular Ca++. The data indicate that vasopressin stimulates phospholipase D which hydrolyzes phosphatidylcholine to phosphatidate. The phosphatidate is then metabolized, presumably by a phosphatidate phosphohydrolase, to produce sustained levels of cellular diacylglycerol. These sustained levels of diacylglycerol may activate protein kinase C and theraby function in the “sustained phase” of cellular responses.
The determination of the decomposition mechanism and kinetics of methoxy on clean Ni(100) and the effects of coadsorbed hydrogen, CO, and sulfur by time-resolved Fourier transform infrared spectroscopy

Abstract Time-resolved Fourier transform infrared spectroscopy (TR-FTIR) was used to simultaneously examine the mechanism and kinetics of methoxy decomposition on Ni(100) under varying conditions. The use of TR-FTIR to obtain kinetic parameters was first validated by comparison to temperature-programmed desorption using annealed CO adlayers. Assuming a first-order reaction with a constant pre-exponential factor of 5.2 × 1012 s−1, we find the activation energy for methoxy decomposition to CO and hydrogen to increase as the reaction proceeds according to 16.9 + 10θCO ± 0.3 kcal/mol, where θCO is the coverage of CO product in monolayers, for initial methoxy coverages between 0.18 and 0.056 ML. The addition of 0.10 ± 0.02 ML of CO increases the energy for CH bond activation to 19.2 ± 0.4 kcal/mol. Coadsorbed sulfur was found to inhibit both methoxy formation and decomposition. The addition of 0.14 ± 0.02 ML of sulfur raises the activation energy for methoxy decomposition by 1 ± 0.4 kcal/mol, an effect similar in magnitude to coadsorbed CO. The preadsorption of 0.4 ML of hydrogen reduces the amount of methoxy formed from a methanol multilayer but does not raise the activation energy for methoxy decomposition. These results are compared to methoxy decomposition studies on Ni(111) and Ni(110).
CONSIDERATIONS ON DEPOLARIZATION OF POSITIVE MUONS IN GASES EFFECT OF MOLECULAR IONS

A brief discussion of various causes of depolarization is given with particular application to muons in gases. The additional depolarizing mechanism suggested is associated with the possible formation of a molecular ion by the attachment of a mu /sup +/ meson to a neutral gas atom or molecule. (L.T.W.)
Elevated serotonergic signaling amplifies synaptic noise and facilitates the emergence of epileptiform network oscillations

Serotonin fibers densely innervate the cortical sheath to regulate neuronal excitability, but its role in shaping network dynamics remains undetermined. We show that serotonin provides an excitatory tone to cortical neurons in the form of spontaneous synaptic noise through 5-HT3 receptors, which is persistent and can be augmented using fluoxetine, a selective serotonin re-uptake inhibitor. Augmented serotonin signaling also increases cortical network activity by enhancing synaptic excitation through activation of 5-HT2 receptors. This in turn facilitates the emergence of epileptiform network oscillations (10–16 Hz) known as fast runs. A computational model of cortical dynamics demonstrates that these two combined mechanisms, increased background synaptic noise and enhanced synaptic excitation, are sufficient to replicate the emergence fast runs and their statistics. Consistent with these findings, we show that blocking 5-HT2 receptors in vivo significantly raises the threshold for convulsant-induced seizures.
Bovine hemoglobin as the sole source of dietary iron does not support adequate iron status in copper-adequate or copper-deficient rats

Abstract This experiment was designed to determine whether dietary hemoglobin (Hgb) iron (Fe) could sustain normal Fe status in growing rats adequate or deficient in copper (Cu). Forty-eight weanling rats were divided into 3 groups, each consisting of 16 animals. One group was fed a diet containing 40 mg Fe/kg as ferrous sulfate (FeSO 4 ). A second and a third group were fed 40 and 70 mg Fe/kg, respectively, as bovine Hgb. Each of these groups was divided into 2 subgroups of 8 rats each and fed 5.0 or less than 0.5 mg Cu/kg. After 4 weeks, Cu and Fe statuses were assessed. Rats fed 40 mg Fe/kg as Hgb were anemic, but not when fed 70 mg Fe/kg as Hgb. Rats fed CuD diets also were anemic compared to CuA rats. Rats fed Hgb Fe at 40 mg/kg had lower ( P 4 ; however, these parameters were normal in rats fed Hgb Fe at 70 mg/kg. Regardless of the dietary Hgb Fe level, Fe concentrations in the intestinal mucosa, liver, and kidney were significantly lower than in rats fed FeSO 4 . Copper was significantly ( P P P P P 4 , but was not affected by CuD. This investigation demonstrates that adequate Fe status cannot be maintained in the growing rat with Hgb as the sole source of dietary Fe.
The isolation of unidentified pleomorphic bacteria from the blood of patients with chronic illness.

Abstract 1. 1. Unidentified pleomorphic bacteria were isolated from the blood of 44 of 100 patients with chronic illness including fevers of unknown origin, lymphomas, chronic brucellosis, cardiovascular disease, and Reiter's disease. In only two instances were similar organisms isolated from so-called normal individuals. 2. 2. A number of the UPB were resistant to penicillin and a few were resistant to other antibiotics. 3. 3. The organisms are morphologically very similar to Corynebacteria and may belong to this genus. 4. 4. None of the UPB were pathogenic for laboratory animals. All, however, were pathogenic for five-day chick embryos.
Electronic structure and magnetism of Ni overlayers on a Cu(001) substrate

Our recently developed linearized augmented-plane-wave thin-film method is used to determine the electronic structure and magnetism of Ni overlayers on Cu(001). Accurate ab initio self-consistent spin-polarized semirelativistic band calculations are reported for (i) a clean five-layer Cu(001) slab and (ii) the same Cu slab plus one or two $p(1\ifmmode\times\else\texttimes\fi{}1)$ layers of Ni on either side. Results presented include charge and spin densities, work function, band structures, projected density of states, magnetic moments, and direct and transferred hyperfine fields. Both surface and interface effects are found to be important. The Ni overlayers are not magnetically dead: The Ni layer adjacent to the Cu has its moment decreased from the bulk value to 0.39${\mathrm{\ensuremath{\mu}}}_{\mathit{B}}$ for the single Ni overlayer and to 0.47${\mathrm{\ensuremath{\mu}}}_{\mathit{B}}$ for the two-Ni-thick layers; the surface Ni layer in the two-layer Ni on Cu film has its moment increased somewhat to 0.68${\mathrm{\ensuremath{\mu}}}_{\mathit{B}}$. This reduction in moment for the interface Ni arises primarily from charge transfer onto Ni sites from the Cu substrate. By contrast, the increase in moment of the Ni surface atoms arises in large part due to the dehybridization of the $p$ electrons from the $d$-band electrons; these $p$ electrons become more delocalized and spill out into the vacuum region. A similar effect was also observed for an unsupported Ni monolayer. In the case of the Ni monolayer on Cu, the total number of Ni electrons is almost the same as for bulk Ni. Here, the loss of electrons due to the dehybridization of $p$ electrons is nearly canceled by the increase from its interface with the Cu substrate; the decrease in magnetic moment (to 0.39${\mathrm{\ensuremath{\mu}}}_{\mathit{B}}$) agrees with electron-capture experiments.
Ensuring valid measurements for a disabled population: an insulin pen pilot study.

Health promotion and self-management for persons with disabilities have been severely underemphasized in health care research. As researchers seek to fill these gaps in knowledge, it is essential that they validate their methods through use of pilot studies. The following pilot study illustrates how such exploration can lead to unexpected and necessary modification of methods. The study focused on measurement of dosing accuracy by blind people using insulin pens. The National Federation of the Blind provided in-kind support for the study. The original study design used a common method for measuring dose accuracy: weighing insulin delivered into a small cup. For the pilot, 12 blind staff members of the U.S. National Federation of the Blind received instruction on insulin pen use and delivered doses into a small cup. Audible “clicks” for each dose were counted and recorded by the researchers, and the cups were weighed immediately before and after each dose using a precision balance. All doses (100%) were dialed correctly according to the click count. However, four doses had greater than 20% error by weight. During the last two of these doses, the principal investigator and research assistant independently noticed a large hanging drop of insulin remaining on the end of the needle. The hanging drop was a source of error for these two doses and may have been an unnoticed source of error for the other two doses. Measurement error produced by hanging drops is much less likely when sighted people deliver a dose, since they could see and shake off the drop. Blind people do not see the drop, and their dosing may seem inaccurate in comparison. This source of error has no clinical significance; anyone using an insulin pen would inject into subcutaneous tissue, which would not leave a hanging drop on the needle. The error is an artifact of the measurement method. Because this source of error was discovered in the pilot study, the measurement method for a larger follow-up study was changed to weighing insulin delivered into an injection ball (a rubber ball used to teach injections), which simulates injection into subcutaneous tissue more closely. If this source of error had not been noticed in pilot testing, the results of the larger study would have been artificially biased. The importance of conducting pilot studies to validate methods with disabled populations cannot be overemphasized. As this pilot study illustrates, a method that is valid in a nondisabled population but not pilot tested with a disabled population could reinforce inaccurate and limiting stereotypes about the true abilities of people with disabilities.