cssi/SciSciGPT-SciSciNet huggingface dataset:
Proton Transfer in Perfluorosulfonic Acid Fuel Cell Membranes with Differing Pendant Chains and Equivalent Weights.

Proton transfer in the nanoscopic water channels of polyelectrolyte fuel cell membranes was studied using a photoacid, 8-hydroxypyrene-1,3,6-trisulfonic acid sodium salt (HPTS), in the channels. The local environment of the probe was determined using 8-methoxypyrene-1,3,6-trisulfonic acid sodium salt (MPTS), which is not a photoacid. Three fully hydrated membranes, Nafion (DuPont) and two 3M membranes, were studied to determine the impact of different pendant chains and equivalent weights on proton transfer. Fluorescence anisotropy and excited state population decay data that characterize the local environment of the fluorescent probes and proton transfer dynamics were measured. The MPTS lifetime and anisotropy results show that most of the fluorescent probes have a bulk-like water environment with a relatively small fraction interacting with the channel wall. Measurements of the HPTS protonated and deprotonated fluorescent bands’ population decays provided information on the proton transport dynamics. Th...
Quantum Simulations of Charge Separation at a Model Donor-Acceptor Interface: Role of Delocalization and Local Packing

Organic Polymer-based photovoltaic systems offer a viable alternative to more standard solid-state devices for light-harvesting applications. In this study, we investigate the electronic dynamics of a model organic photovoltaic (OPV) heterojunction consisting of polyphenylene vinylene (PPV) oligomers and a -phenyl C61-butyric acid methyl ester (PCBM) blend. Our approach treats the classical molecular dynamics of the atoms within an Ehrenfest mean-field treatment of the - singly excited states spanning a subset of donor and acceptor molecules near the phase boundary of the blend. Our results indicate that interfacial electronic states are modulated by C=C bond stretching motions and that such motions induce avoided crossings between nearby excited states thereby facilitating transitions from localized excitonic configurations to delocalized charge-separated configurations on an ultrafast time-scale. The lowest few excited states of the model interface rapidly mix allowing low frequency C-C out-of-plane torsions to modulate the potential energy surface such that the system can sample both intermolecular charge-transfer and charge-separated electronic configurations on sub-100 fs time scales. Our simulations support an emerging picture of carrier generation in OPV systems in which interfacial electronic states can rapidly decay into charge-separated and current producing states via coupling to vibronic degrees of freedom.
Abstract 467: Nitric Oxide-Mediated Regulation of the Adiponectin-Adiponectin Receptor Pathway Following Arterial Injury

Objectives Nitric oxide (NO) has been shown to limit the development of neointimal hyperplasia; however, little is known about its effects on the adventitia. Adiponectin is a molecule that originates from periadventitial adipose tissue and has been shown to negatively regulate neointimal growth. Thus, we hypothesize that removal of periadventitial fat from the arterial wall will negatively impact the ability of NO to inhibit the development of neointimal hyperplasia following injury. Methods The carotid artery injury model was performed on 11-week-old Sprague Dawley rats. Animal models underwent either removal of all periadventitial fat from the artery at the time of surgery (absent) or no disturbance of the periadventitial fat (present). Treatment groups included control, injury, and injury + NO (PROLI/NO, 10mg). Arteries were harvested at 2 weeks. Morphometric analysis was performed using ImageJ software. Immunofluorescent staining was performed for the adiponectin receptor (AR) and assessed using blinded grading (scale 0-4). Results Morphometric analysis revealed a 29% increase in neointima development in the absent vs. present group (p Conclusions Removal of the source of periadventitial adiponectin resulted in more neointimal hyperplasia following arterial injury, but a paradoxical NO-mediated increase in AR levels and corresponding responsiveness to NO therapy. These data suggest that AR expression is upregulated in the absence of adiponectin by NO. Further studies that identify the mechanism by which NO may regulate adiponectin may provide a novel therapeutic target to prevent neointimal hyperplasia.
Numerical simulation of ion transport membrane reactors: Oxygen permeation and transport and fuel conversion

Abstract Ion transport membrane (ITM) based reactors have been suggested as a novel technology for several applications including fuel reforming and oxy-fuel combustion, which integrates air separation and fuel conversion while reducing complexity and the associated energy penalty. To utilize this technology more effectively, it is necessary to develop a better understanding of the fundamental processes of oxygen transport and fuel conversion in the immediate vicinity of the membrane. In this paper, a numerical model that spatially resolves the gas flow, transport and reactions is presented. The model incorporates detailed gas phase chemistry and transport. The model is used to express the oxygen permeation flux in terms of the oxygen concentrations at the membrane surface given data on the bulk concentration, which is necessary for cases when mass transfer limitations on the permeate side are important and for reactive flow modeling. The simulation results show the dependence of oxygen transport and fuel conversion on the geometry and flow parameters including the membrane temperature, feed and sweep gas flow, oxygen concentration in the feed and fuel concentration in the sweep gas.
Approximate Distributional Results Based on the Maximum Likelihood Estimators for the Weibull Distribution

Simple approximations which are useful for constructing confidence intervals for the parameters, tolerance limits and confidence limits on reliability, based on maximum likelihood estimators, are studied in this paper. A new approximation for the distri..
Orbital symmetry and the optical response of single-layer MX monochalcogenides

We show that the absorption spectra of single-layer GaSe and GaTe in the hexagonal phase feature exciton peaks with distinct polarization selectivity. We investigate these distinct features from first-principles calculations using the GW-BSE formalism. We show that, because of the symmetry of the bands under in-plane mirror symmetry, the bound exciton states selectively couple to either in-plane or out-of-plane polarization of the light. In particular, for a p-polarized light absorption experiment, the absorption peaks of the hydrogenic s-like excitons emerge at large angle of incidence, while the overall absorbance reduces over the rest of the spectrum.
Public Health Issues in 2016 Presidential Campaign Communications.

An editorial is presented which addresses the authors' views about the communication of various public health issues during the 2016 U.S. presidential campaign, and it mentions how then-American presidential candidates Donald Trump and Hillary Clinton rarely discussed public health topics during the 2016 campaign. Issues such as mental health and health care costs in America are examined, along with children's health care and the U.S. Patient Protection and Affordable Care Act.
Bounded Point Derivations on Certain Function Algebras

Let X be a compact nowhere dense subset of the complex plane ℂ, let C(X) be the linear space of all continuous functions on X endowed with the uniform norm, and let dA denote two-dimensional Lebesgue (or area) measure in ℂ. Denote by R(X) the closure in C(X) of the set of all rational functions having no poles on X. It is well known that if X is sufficiently massive, then the functions in R(X) can inherit many of the properties usually associated with the analytic functions, such as unlimited degrees of differentiability and even the uniqueness property itself. Here we shall examine the extent to which some of those properties are inherited by the larger algebra H ∞ (X), which by definition is the weak-* closure of R(X) in L∞(X) = L∞(X, dA).
Primary prevention of chronic kidney disease through population-based strategies for blood pressure control: The ARIC study

While much of the chronic kidney disease (CKD) literature focuses on the role of blood pressure reduction in delaying CKD progression, little is known about the benefits of modest population-wide decrements in blood pressure on incident CKD. The authors used multivariable linear regression to characterize the impact on incident CKD of two approaches for blood pressure management: (1) a 1-mm Hg reduction in systolic BP across the entire study population; and (2) a 10% reduction in participants with unaware, untreated, and uncontrolled BP above goal as defined by the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) thresholds. Over a mean of 20 years of follow-up (ARIC [Atherosclerosis Risk in Communities] study, n = 15 390), 3852 incident CKD events were ascertained. After adjustment, a 1-mm Hg decrement in systolic BP across the population was associated with an estimated 11.7 (95% confidence interval [CI], 6.2-17.3) and 13.4 (95% CI, 10.3-16.6) fewer CKD events per 100 000 person-years in blacks and whites, respectively. Among participants with BP above JNC 7 goal, a 10% decrease in unaware, untreated, or uncontrolled BP was associated with 3.2 (95% CI, 2.0-4.9), 2.8 (95% CI, 1.8-4.3), and 5.8 (95% CI, 3.6-8.8) fewer CKD events per 100 000 person-years in blacks and 3.1 (95% CI, 2.3-4.1), 0.7 (95% CI, 0.5-0.9), and 1.0 (95% CI, 1.3-2.4) fewer CKD events per 100 000 person-years in whites. Modest population-wide reductions in systolic BP hold potential for the primary prevention of CKD.
Usability problem description and the evaluator effect in usability testing

Previous usability evaluation method (UEM) comparison studies have noted an evaluator effect on problem detection in heuristic evaluation, with evaluators differing in problems found and problem severity judgments. There have been few studies of the evaluator effect in usability testing (UT), task-based testing with end-users. UEM comparison studies focus on counting usability problems detected, but we also need to assess the content of usability problem descriptions (UPDs) to more fully measure evaluation effectiveness. The goals of this research were to develop UPD guidelines, explore the evaluator effect in UT, and evaluate the usefulness of the guidelines for grading UPD content. Ten guidelines for writing UPDs were developed by consulting usability practitioners through two questionnaires and a card sort. These guidelines are (briefly): be clear and avoid jargon, describe problem severity, provide backing data, describe problem causes, describe user actions, provide a solution, consider politics and diplomacy, be professional and scientific, describe your methodology, and help the reader sympathize with the user. A fourth study compared usability reports collected from 44 evaluators, both practitioners and graduate students, watching the same 10-minute UT session recording. Three judges measured problem detection for each evaluator and graded the reports for following 6 of the UPD guidelines. There was support for existence of an evaluator effect, even when watching prerecorded sessions, with low to moderate individual thoroughness of problem detection across all/severe problems (22%/34%), reliability of problem detection (37%/50%) and reliability of severity judgments (57% for severe ratings). Practitioners received higher grades averaged across the 6 guidelines than students did, suggesting that the guidelines may be useful for grading reports. The grades for the guidelines were not correlated with thoroughness, suggesting that the guideline grades complement measures of problem detection. A simulation of evaluators working in groups found a 34% increase in severe problems found by adding a second evaluator. The simulation also found that thoroughness of individual evaluators would have been overestimated if the study had included a small number of evaluators. The final recommendations are to use multiple evaluators in UT, and to assess both problem detection and description when measuring evaluation effectiveness.
The Role of Nutritional and Pharmacological Antioxidants in the Treatment of Cardiovascular Disease

Vitamin E deficiency was first described as a deficiency disease in 1922 by Evans and Bishop; it was found to prevent fetal resorption in the laboratory rat. Neurological disorders were first described in 1928, when researchers observed paralysis in suckling offspring of vitamin-E-deficient rats. In the following decade, nutritional encephalomalacia was described in the chicken.
Explicit and Implicit Lifetime Assessment Methods of 9Cr-1Mo Steel Under Combined Creep and Fatigue Loads Using a Strip Yield Model

Growing demand for clean, affordable energy has driven the power industry towards generation plants with higher thermal efficiency and higher operating temperatures. ASTM Grade 91 is a high chromium (9Cr-1Mo) creep resistant steel commonly used in high temperature pressure vessel and piping applications. These service conditions often involve a combination of stationary and cyclic loads at elevated temperatures. Lifecycle assessments of components under such conditions require modeling of both creep and fatigue behaviors. This paper develops two approaches to modeling mixed creep and fatigue crack growth for lifetime assessment of high service temperature components. Both approaches model fatigue crack growth using the Paris law integrated over the number of lifetime cyclic reversals to obtain crack extension. A strip yield model is used to characterize the crack tip stress-strain fields.The first approach employed an explicit method to approximate creep crack growth using C* as a crack tip parameter characterizing creep crack extension. The Norton power law was explicitly solved to model the primary and secondary stages of creep.The second approach used an implicit method to solve a set of constitutive equations based on properties of the material microstructure to model all creep stages. Constitutive equations were fit to experimental data collected at stresses 10–60% of yield and temperatures 550–650°C. These methods were compared to published experimental data under purely stationary loads, purely cyclic loads and mixed loading. Both models showed good agreement with experimental data in the stress and temperature conditions considered.Copyright © 2014 by ASME
A retrospective cohort analysis of the effects of renin-angiotensin system inhibitors on spinal fusion in ACDF patients

Abstract BACKGROUND CONTEXT Recently, preclinical and clinical studies suggest an association between renin-angiotensin system (RAS) blockers and bone healing, particularly in the context of osteoporotic bone fractures. PURPOSE To determine the correlation between the use of RAS inhibitors and fusion outcomes and neurologic status in anterior cervical discectomy and fusion (ACDF) surgery. STUDY DESIGN Retrospective observational study. PATIENT SAMPLE Patients who underwent ACDF for degenerative disorders. OUTCOME MEASURES Spinal fusion status and neurologic function (modified Japanese Orthopedic Association [mJOA] and Nurick grading scales). METHODS A retrospective chart review was performed, including 200 patients who underwent ACDF for degenerative disorders with 1-year minimum follow-up. Demographic data, comorbidities, antihypertensive medication, neurologic examination, and fusion status were collected. Spinal fusion was assessed via plain cervical x-ray, resorting to dynamic radiographs and/or computer tomography (CT) in cases of uncertainty. Preoperative mJOA and Nurick scores and recovery rates were calculated to determine neurologic status. RESULTS Of the 200 patients (42.5% females, 57.5% males, median age of 53.7 years), 82 hypertensive patients were identified. Seventy-seven (93.9%) were taking antihypertensive medication as follows: 36.4% angiotensin-II receptor blockers (ARBs), 35.1% angiotensin-converting enzyme inhibitors (ACEIs), and the remaining patients were taking other medication. In the analysis of fusion rates, patients treated with ARBs exhibited a higher fusion rate, while those treated with ACEIs displayed a lower fusion rate compared to untreated nonhypertensive patients (p = .04 and .02, respectively). The difference in fusion rates between ARBs and ACEIs was also significant, with the former displaying higher rates (p CONCLUSIONS In ACDF patients, we observed that ARBs were associated with higher fusion rates. Conversely, ACEIs and smoking were related to failed fusion. Prospective case-control studies are needed to confirm these RAS inhibitors effects on spinal fusion.
Oxide rupture-induced conductivity in liquid metal nanoparticles by laser and thermal sintering

Metallic inks with superior conductivity and printability are necessary for high-throughput manufacturing of printed electronics. In particular, gallium-based liquid metal inks have shown great potential in creating soft, flexible and stretchable electronics. Despite their metallic composition, as-printed liquid metal nanoparticle films are non-conductive due to the surrounding metal oxide shells which are primarily Ga2O3, a wide-bandgap semiconductor. Hence, these films require a sintering process to recover their conductivity. For conventional solid metallic nanoparticles, thermal and laser processing are two commonly used sintering methods, and the sintering mechanism is well understood. Nevertheless, laser sintering of liquid metal nanoparticles was only recently demonstrated, and to date, the effect of thermal sintering has rarely been investigated. Here, eutectic gallium–indium nanoparticle films are processed separately by laser or thermal sintering in an ambient environment. Laser and thermally sintered films are compared with respect to electrical conductivity, surface morphology and elemental composition, crystallinity and surface composition. Both methods impart thermal energy to the films and generate thermal stress in the particles, resulting in rupture of the gallium oxide shells and achieving electrical conductivity across the film. For laser sintering, extensive oxide rupture allows liquid metal cores to flow out and coalesce into conductive pathways. For thermal sintering, due to less thermal stress and more oxidation, the oxide shells only rupture locally and extensive phase segregation occurs, leading to non-liquid particle films at room temperature. Electrical conductivity is instead attributed to segregated metal layers and gallium oxide which becomes crystalline and conductive at high temperatures. This comprehensive comparison confirms the necessity of oxidation suppression and significant thermal stress via instantaneous laser irradiation to achieve conductive patterns in liquid form.
Variability in Noninvasive Vascular Laboratory Experience of Vascular Surgery Training Programs Based on Survey of Trainees Suggests the Need for a Standardized Curriculum

Background Although a Registered Physician in Vascular Interpretation certification is required for vascular surgery board certification, no standardized noninvasive vascular laboratory (NIVL) curriculum for vascular surgery trainees exists. The purpose of this study is to investigate the NIVL experience of trainees and understand what helps them feel well prepared. Methods Current trainees in all 0 + 5 and 5 + 2 vascular surgery training programs (114) were surveyed. The most complete survey from each program was included in the analysis. Programs were divided into those in which trainees felt well prepared (WP) and those in which trainees felt unprepared (UP) for the Physician Vascular Interpretation (PVI) examination. Responses for the 2 groups were compared. Results Responses from 61 of the 114 programs (53.5%) were analyzed. Most programs devote Conclusions There is wide variation in NIVL experience among vascular surgery training programs. Many trainees feel unprepared for the PVI examination, especially those without a structured curriculum. These results suggest that a structured NIVL curriculum that includes dedicated time with vascular technologists, lectures, and articles should be established.
Molecular Oxygen Activation on Suspended Doped Cerium(IV) Oxide Particles in Molten Chloride Salts

Suspensions of cerium(IV) oxide (CeO2) particles in molten chloride salts were found to be active for molecular oxygen activation when doped with the larger Lanthanides, gadolinium (Gd), praseodymium, (Pr), and samarium, (Sm). The activity for O2 oxidation of gas phase CO on suspended doped ceria in molten mixtures of LiCl–LiBr–KBr and NaCl–KCl is significantly higher than undoped ceria or the salt mixtures alone in the temperature ranges of 350–600 °C, and 700–800 °C, respectively. Surface tension measurements show that the solid doped ceria particles suspended in the melt are contacting the gas–liquid interface of the bubbles. The activity for O2 oxidation of liquid phase MgCl2 in molten MgCl2–KCl to produce Cl2 and solid MgO was also observed to be significantly increased on suspended CeO2 doped with 5 wt% or 10 wt% Gd. The rates of oxidation were observed to increase with catalyst loading.
What Lawyers Can Learn from Edgar Allan Poe

Treat yourself to a spine-tingling Edgar Allan Poe sensation by reading about the synergy between stories of horror and legal writing. Poe defined a short-story writing technique and named four qualities—brevity, unity, focus, and brilliant style—as critical. These exact same qualities are familiar to lawyers because they are just as critical for persuasive briefs. This article examines Poe’s critique of Nathaniel Hawthorne’s Twice-Told Tales, reviews some of Poe’s own work, and applies Poe’s advice about great short-story writing to legal writing.
Physics-Informed and Hybrid Machine Learning in Additive Manufacturing: Application to Fused Filament Fabrication

This article investigates several physics-informed and hybrid machine learning strategies that incorporate physics knowledge in experimental data-driven deep-learning models for predicting the bond quality and porosity of fused filament fabrication (FFF) parts. Three types of strategies are explored to incorporate physics constraints and multi-physics FFF simulation results into a deep neural network (DNN), thus ensuring consistency with physical laws: (1) incorporate physics constraints within the loss function of the DNN, (2) use physics model outputs as additional inputs to the DNN model, and (3) pre-train a DNN model with physics model input-output and then update it with experimental data. These strategies help to enforce a physically consistent relationship between bond quality and tensile strength, thus making porosity predictions physically meaningful. Eight different combinations of the above strategies are investigated. The results show how the combination of multiple strategies produces accurate machine learning models even with limited experimental data.
Coagulation status, fibrinolysis, and platelet dynamics in dogs with chronic inflammatory enteropathy.

Background Coagulation status is poorly understood in dogs with chronic inflammatory enteropathy (CIE). Fibrinolytic activity and platelet dynamics have not been evaluated in CIE dogs. Objectives To assess coagulation status and fibrinolysis in normoalbuminemic CIE dogs (CIE-N) and CIE dogs with protein-losing enteropathy (CIE-PLE) compared to healthy controls (HC). To evaluate thromboelastography (TEG) variable differences between groups and for correlations with clinicopathologic data. To report platelet dynamics in CIE dogs. Animals Twenty-five client-owned dogs with CIE (n = 16 CIE-N; n = 9 CIE-PLE); 14 HC beagle dogs. Methods All dogs had tissue factor + tissue plasminogen activator TEG. Nine of 25 CIE dogs had whole blood impedance platelet aggregometry. The TEG variables and coagulation data were compared between all CIE vs HC dogs, CIE-N dogs vs HC, and CIE-PLE dogs vs HC. Clinicopathologic and coagulation data were available for CIE dogs and assessed for correlation to TEG variables. Results Dogs with CIE had higher maximum amplitude (MA; P Conclusions and clinical importance Normoalbuminemic and hypoalbuminemic CIE dogs were considered hypercoagulable based on TEG compared to HC. Some CIE dogs displayed hypofibrinolytic phenotypes on TEG.
Medical complexity and concurrent hospice care: A national study of Medicaid children from 2011 to 2013

Purpose Pediatric hospice is a comprehensive model of care for medically complex children at end of life. The Affordable Care Act changed regulatory requirements for pediatric Medicaid enrollees to allow for enrollment into hospice services while still receiving life-prolonging therapy. There are gaps in understanding factors associated with pediatric concurrent hospice care use. The objectives were to examine the prevalence of concurrent hospice care overtime and investigated the relationship between medical complexity and concurrent hospice care among Medicaid children. Design and methods We used national Medicaid data and included children less than 21 years with an admission to hospice care. Medical complexity was defined with four criteria (i.e., chronic conditions, functional limitations, high health care use and substantial needs). Using multivariate logistic regression, we evaluated the influence of medical complexity on concurrent hospice care use, while controlling for demographic, hospice, and community characteristics. Results Thirty-four percent of the study sample used concurrent hospice care. Medical complexity was unrelated to concurrent hospice care. However, the four individual criteria were associated. A complex chronic condition was negatively related to concurrent hospice care, whereas technology dependence, multiple complex chronic conditions, and mental/behavioral disorders were positively associated to concurrent care use. Practice implications These findings suggest that concurrent hospice care may be important for a subset of medically complex children with functional limitations, high health utilization, and substantial needs at end of life.
Forgone Medical Care Associated With Increased Health Care Costs Among the U.S. Heart Failure Population.

Abstract Objectives The objective of this study was to describe the prevalence of patients with forgone/delayed care for heart failure (HF) and examine the associated demographic characteristics, health care utilization, and costs. Background HF is a leading cause of morbidity and mortality, with health care expenditures projected to increase 3-fold from 2012 to 2030. The proportion of HF patients with forgone/delayed medical care and the association with health care expenditures and utilization remain unknown. Methods Data on patients with HF were obtained from the Medical Expenditure Panel Survey to assess expenditures and health care utilization in the United States from 2004 to 2015. Patients with HF who reported forgone/delayed care, any missed or delayed medical treatment, were compared with those without care lapses. Results Overall, 16% of patients with HF reported forgone/delayed care, including 10% among the elderly (aged ≥65 years) and 27% among the nonelderly (aged Conclusions Nearly 1 in 6 patients with HF in the United States reported forgone/delayed medical care, with one-half attributing it to financial reasons, and this was associated with higher overall health care spending.
Criminal achievement, criminal self-efficacy, and the criminology of Carlo Morselli: suggestions for continuing and extending a fruitful line of inquiry

The unique scholarship of Carlo Morselli fuelled interest in criminal networks, entrepreneurship, and achievement. In this paper, we summarise Morselli’s contributions to the scholarship on crimina...
Using Automatic Case Splits and Efficient CNF Translation to Guide a SAT-solver when Formally Verifying Out-Of-Order Processors.

The paper integrates automatically generated case-splitting expressions, and an efficient translation to CNF, in order to formally verify an out-of-order superscalar processor having register renaming, as well as Reorder Buffer and Reservation Stations that are completely implemented and instantiated. The processor was defined in the high-level Hardware Description Language AbsHDL, based on the logic of Equality with Uninterpreted Functions and Memories (EUFM), and was formally verified with an extended version of the decision procedure EVC, combined with a SAT-solver. The manual work was limited to definition of necessary invariant constraints. The formal verification was decomposed, based on automatically generated case-splitting expressions—matching Recorder Buffer entries with Reservation Stations to compute the results for those Reorder Buffer entries, and allowing for orders of magnitude speedup if many CPUs are available for parallel runs of EVC. Efficient translation from EUFM to CNF—by producing more ITEs, and merging ITE-trees with 2 levels of their leaves—resulted in additional 32× speedup.
Resistance and susceptibility to infection in inbred murine strains: II. Variations in the effect of treatment with thymosin fraction 5 on the release of lymphokines in vivo

Abstract Of nine inbred murine strains sensitized intravenously with killed lyophilized Candida albicans and challenged 3 weeks later with a C. albicans filtrate, four strains were low responders and five were high responders in the in vivo release of migration inhibitory factor (MIF) and gamma interferon (IFN-γ). An identical distribution of high- and low-responder strains occurred in response to sensitization with Mycobacterium bovis BCG and subsequent challenge with old tuberculin. Treatment of the murine strains with thymosin fraction 5 prior to sensitization and challenge had different effects: (a) the high-responder strains had a decrease in their release in vivo of the two lymphokines; (b) three of five of the low-responder strains had a striking increase in the in vivo release of MIF and IFN-γ; and (c) one low-responder strain did not have its response altered. A parallelism existed between the capacity of a murine strain to release the two lymphokines in vivo on stimulation with C. albicans antigens and the capacity of that strain to resist intravenous infection with living C. albicans .
Spatial representation and reasoning for human-robot collaboration

How should a robot represent and reason about spatial information when it needs to collaborate effectively with a human? The form of spatial representation that is useful for robot navigation may not be useful in higher-level reasoning or working with humans as a team member. To explore this question, we have extended previous work on how children and robots learn to play hide and seek to a human-robot team covertly approaching a moving target. We used the cognitive modeling system, ACT-R, with an added spatial module to support the robot's spatial reasoning. The robot interacted with a team member through voice, gestures, and movement during the team's covert approach of a moving target. This paper describes the new robotic system and its integration of metric, symbolic, and cognitive layers of spatial representation and reasoning for its individual and team behavior.
Sarcolipin overexpression in mice increases their endurance exercise capacity (1162.2)

Sarcolipin (SLN) is a transmembrane protein that interacts with Sarco(endo)plasmic Reticulum Calcium ATPase (SERCA) and is expressed in cardiac and skeletal muscle. SLN is known to inhibit Vmax of ...
Functionally important residues at a subunit interface site in the RecA protein from Escherichia coli

Assembly of RecA subunits into long, helical oligomers is required for its roles in recombinational DNA repair and homologous genetic recombination. The crystal structure of RecA reveals an extensive network of amino acid residues that lie at the subunit boundaries. We have introduced a large set of substitutions at 5 clustered residues, which are shown in the crystal structure to make specific contacts with positions in the neighboring monomer. We find that 3 of the 5 residues are important for RecA function (Lys216, Phe217, and Arg222), whereas the other 2 (Asn213 and Tyr218) are not. The patterns of functionally allowed substitutions provide insight into the chemical and steric constraints required at these positions.
Effects of fracture stabilization by internal fixation: I. A haemodynamic and blood gas evaluation of the systemic and regional changes☆

Abstract The effect of internal stabilization of a fracture of the femur on arterial blood oxygen levels, limb blood flow and oxygen consumption was measured in 24 dogs. Those with stabilized fractures bore weight on their limbs and were much more active. Without fracture stabilization the arterial oxygen tension fell by 10 per cent. With internal fixation this hypoxia did not develop. In fact, there was a 10 per cent increase beginning in the third week. Stabilization of the fracture gave a persistent increase in limb blood flow, but without stabilization this increase was transient and followed by a significant decrease. Over the 7-week observation period, the total oxygen consumption of the uninjured limbs in the stabilized group was twice that in the unstabilized group, an indication of their functional activity. Also with stabilization, the oxygen consumption of the injured limb was not significantly different from the opposite limb, whereas without stabilization the consumption was 32 per cent greater, an indication of the energy cost of countering instability.
Image based search engine

We are in the process of improving an image-based search engine, capable of using distributed computing techniques to locate one image in another, regardless of scale or orientation. With the continuing expansion of the Internet, users have access to more media content than ever. It is important to redesign this search engine to take advantage of present and future resources as well as to realize the full capabilities in the searching of images.
Tetranitromethane modification of photosystem 2.

Inhibition of photosystem 2 by the peptide-modification reagent, tetranitromethane, has been investigated with spinach digitonin particles. In the presence of tetranitromethane, (1) the initial fluoresence yield is suppressed with a concomitant elimination of the variable component of fluorescence; (2) the optical absorption transient at 820 nm, attributed to P680+, is greatly attenuated; (3) diphenylcarbazide-supported photoreduction of dichlorophenol indophenol is abolished; and (4) electron spin resonance Signal 2f and Signal 2s are eliminated. These results are consistent with multiple sites of modification in photosystem 2 by tetranitromethane, and suggest further that this reagent can inhibit charge stabilization in the reaction center.
System Green functions for interacting quantum particles

We propose a formalism for the study of many-particle interacting quantum systems that allows the determination of the Green function of the system as a whole and corresponding Green functions of lower order from a knowledge of any Green function of a higher order. We illustrate the formalism by means of calculations on a model single-band system described by a Hamiltonian of tight-binding kind and corresponding to four electrons on a ring of four sites.
Clinical Outcome of Patients Undergoing Endoluminal Coronary Artery Reconstruction With Three or More Stents

Abstract Objectives. We sought to evaluate the outcome of patients undergoing multiple (three or more), contiguous stent implantation within a single native coronary artery. Background. The implantation of multiple stents within a single coronary artery is increasing in frequency, although the outcome of such patients is not well described. Methods. Forty-five patients without previous coronary artery bypass graft surgery (CABG) undergoing multiple, contiguous stent implantation in a single coronary artery were identified. Clinical and angiographic characteristics and outcomes were analyzed. Results. The angiographic success rate was 97.8%. The procedural success rate was 91.1%; stent occlusion during the initial hospital period occurred in four patients (8.9%). Death, myocardial infarction (MI), CABG, repeat target vessel intervention or severe angina occurred in 10 (23.3%) of 43 hospital survivors at 6-month follow-up. The indication for stent placement was threatened or abrupt closure in 30 patients (66.7%). Of the 25 patients with abrupt or threatened closure whose clinical and angiographic data would have indicated emergent CABG had stents not been available, the frequency of in-hospital death and Q wave MI was similar to that of a matched consecutive series of patients at our institution who underwent emergent CABG after failed angioplasty. At 1 year, the frequency of death, Q wave MI, CABG and severe angina at 1 year was similar in the two groups; the need for repeat percutaneous intervention was more common in the stent group (25% vs. 0%, p = 0.01). Conclusions. Implantation of multiple, contiguous intracoronary stents was associated with a high initial success rate, although the incidence of early stent closure was relatively high. Adverse events at 6 months of follow-up were more frequent than previously reported for elective single-stent implantation; however, adverse angiographic characteristics such as dissection and thrombus were frequent in this group. In addition, the strategy of multiple stent implantation in the setting of failed angioplasty is a reasonable alternative to emergent CABG, although the need for further percutaneous intervention must be anticipated.
Definitions and the genetic bases of beneficent behavior

I n a recent paper (Rothstein and Pierotti 1988), we reviewed the distinctions and similarities between reciprocal altruism (RA) and other forms of cooperative/beneficent behavior and developed models for the initial evolution of such phenomena. Symons (1989a) raised two issues concerning our paper. We believe that one of these issues is mistaken but that Symons is justified in raising it, given a lack of sufficient precision in one of our definitions. Symons suggests that we should consider a type of by-product beneficence (BB) not mentioned in our paper. We defined BB (p. 200) as a situation in which ” . . . one individual aids another as a result of its own selfish behavior. . .” Following this definition, we modeled two cases with different payoffs to determine whether BB can increase from an initial frequency near zero in an unstructured population. In case I, individuals whose actions cause BB (BBers) receive the same gross benefits (i.e., benefits before costs are subtracted) whether they associate with another BBer or with a no-BBer (an individual who lacks the BB trait). In case 2. a BBer receives more benefits if it associates with another BBer than if it associates with a no-BBer. In both cases, no-BBers receive more net benefits than BBers when the two associate because only the latter pay the costs of BB. We pointed out that the modeling could be made more elaborate by considering other cases, e.g., the possibility that the gross benefits received by a no-BBer exceed those received by a BBer.
Ethanol potentiates the stimulatory effects of phorbol ester, sphingosine and 4‐hydroxynonenal on the hydrolysis of phosphatidylethanolamine in NIH 3T3 cells

Ethanol and other alcohols have been shown to specifically stimulate phospholipase-d-mediated hydrolysis of phosphatidylethanolamine (PtdEtn) in NIH 3T3 fibroblasts. Here, we further examined the possible mechanism of this ethanol action. Ethanol (10–300 mM) and the protein kinase C (PKC) activator 12-O-tetradecanoylphorbol 13-acetate (TPA) had synergistic stimulatory effects on the degradation of preformed [14C]PtdEtn when added in combination to [14C]ethanolamine-labelled suspended NIH 3T3 cells 30 min after collection of cells by scraping. Scraping caused a transient increase, lasting for less than 30 min, in the cellular content of 1,2-diacylglycerol, another PKC activator. Initially (0–50 min incubation), the main water-soluble product of [14C]PtdEtn degradation in ethanol plus TPA-treated cells was [14C]ethanolamine, while later (90 min) the main product of [14C]PtdEtn hydrolysis was [14C]ethanolamine phosphate in the presence of these agents. Ethanol also potentiated the specific stimulatory effects of sphingosine (through phospholipase D) and 4-hydroxynonenal (not involving phospholipase D) on PtdEtn hydrolysis. The effects of these latter agents were unrelated to PKC activation. These data indicate that the observed potentiating effects of ethanol on PtdEtn hydrolysis do not involve direct regulation of PKC or phospholipase D activities.
The horrors of smoking

Blood and smoke . Stephen King. New York: Simon & Schuster Audio, 1999, $23.50 (audiocassette), $27.50 (CD), 3.5 hours. ISBN 0671046160 (cassette)/0671046179 (CD) I have never read a book by Stephen King. But I couldn't resist buying Blood and smoke , available only as an audiobook and read engagingly by King himself. It comes in a flip top box resembling a pack of Marlboros, and contains a CD or three audiocassette tapes, depending on the version you buy. The “book” is actually a series of three short stories, which, according to the packaging, take the listener “inside the world of yearning and paranoia, isolation and addiction . . . the world of the smoker”. “The now politically incorrect habit plays a key role in the fates of three different men in three unabridged stories of unfiltered suspense.” In Lunch at the Gotham Cafe , Steve Davis is distraught after his wife leaves him. Two days later he quits smoking, after a 20 year history of smoking 20–40 cigarettes a day. For the next two weeks he suffers intense withdrawal from nicotine and his wife, until he meets her and her divorce lawyer for lunch at a Manhattan restaurant. While arguing at the table, they are attacked suddenly by a psychotic, knife-wielding maitre d'. Davis fights him off bravely, saving his own life and that of …
Epitope-tagged insulin-like growth factor-I expression in muscle

Abstract Development of a recombinant insulin like growth factor I (IGF-I) that is distinguishable from its endogenous counterpart would provide a powerful tool for delineating the role of IGF in myogenesis. Therefore, the objective of this study was to create an epitope-tagged IGF-I that retains biological activity and determine whether expression of this construct is possible in muscle tissue following direct DNA injection. Expression vectors were created that encoded porcine IGF-I containing a T7 (11-amino acid) epitope-tag (TIGF). Immunoreactivity of the purified recombinant TIGF was confirmed using monoclonal antibodies. Biological activity was evaluated by examining differentiation of myoblasts cultured with TIGF or transfected with TIGF plasmid DNA. Addition of purified TIGF to myoblast cultures stimulated (P –5 M). Likewise, transfection of L6A1 with TIGF DNA hastened (P
Apigenin, a dietary flavonoid, sensitizes human T cells for activation-induced cell death by inhibiting PKB/Akt and NF-κB activation pathway

Resistance of T cells to activation-induced cell death (AICD) is associated with autoimmunity and lymphoproliferation. We found that apigenin (4',5,7-trihydroxyflavone), a non-mutagenic dietary flavonoid, augmented both extrinsic and intrinsic pathways of apoptosis in recurrently activated, but not in primarily stimulated, human blood CD4+ T cells. Apigenin potentiated AICD by inhibiting NF-kappaB activation and suppressing NF-kappaB-regulated anti-apoptotic molecules, cFLIP, Bcl-x(L), Mcl-1, XIAP and IAP, but not Bcl-2. Apigenin suppressed NF-kappaB translocation to nucleus and inhibited IkappaBalpha phosphorylation and degradation in response to TCR stimulation in reactivated peripheral blood CD4 T cells, as well as in leukemic Jurkat T cell lines. Among the pathways that lead to NF-kappaB activation upon TCR stimulation, apigenin selectively inhibited PI3K-PKB/Akt, but not PKC-theta activation in the human T cells, and synergized with a PI3K inhibitor to markedly augment AICD. Apigenin also suppressed expression of anti-apoptotic cyclooxygenase 2 (COX-2) protein in activated human T cells, but it did not affect activation of Erk MAPKinase. Thus, in chronically activated human T cells, relatively non-toxic apigenin can suppress anti-apoptotic pathways involving NF-kappaB activation, and especially cFLIP and COX-2 expression that are important for functioning and maintenance of immune cells in inflammation, autoimmunity and lymphoproliferation.
Adherence of a virulent strain of Listeria monocytogenes to the surface of a hepatocarcinoma cell line via lectin-substrate interaction.

Listeria monocytogenes was examined for the presence of surface carbohydrates to ascertain whether surface sugars, if present, would interact with eucaryotic surface carbohydrate receptors. We found that a virulent, but not two avirulent strains had a surface α-d-galactose residue as determined by agglutination with Griffonia simplicifolia (GS-I) and other lectins. The virulent strain bound to a human hepatocarcinoma cell line (HepG2), which has a well characterized receptor for α-d-galactose. This interaction could be blocked by pretreatment of the HepG2 cells with either α-d-galactose or neuraminidase, the latter of which will render the galactose receptor functionally inactive. We propose that the attachment of the virulent Listeria to eucaryotic cells occurs as a result of the interaction of the microbial α-d-galactose with that of the eucaryotic galactose receptor. This surface carbohydrate may provide an explanation for the mechanism of attachment and penetration of virulent Listeria into host cells during infection. As such, this may allow for amplication of pathogenesis through intracellular multiplication in nonprofessional phagocytes prior to macrophage involvement.
Relationships between disability measures and nursing effort during medical rehabilitation for patients with traumatic brain and spinal cord injury

Abstract Objective: The increasing use of disability measures requires that the validity of these instruments be adequately demonstrated. This study sought to evaluate the concurrent validity of one disability measure, the Functional Independence Measure (FIM SM ) using minutes of care reported by nursing staff. Study Design: Correlational, cohort design. Setting: Eight inpatient medical rehabilitation hospitals that subscribe to the Uniform Data System for Medical Rehabilitation. Patients or Other Participants: 129 patients with traumatic brain injury (TBI) and 53 patients with traumatic spinal cord injury (SCI). Interventions: Routine rehabilitation care. Main Outcome Measures: Patient-nurse contact times were recorded with a stop watch for a 24-hour period during the first and last weeks of inpatient rehabilitation. The FIM was also completed during the first and last weeks of rehabilitation. Results: Contact times declined from the first to last weeks of rehabilitation, concurrent with improving scores on motor and cognitive measures derived from the FIM. Statistically significant correlations between contact times and FIM measures were observed for medication dispensing, treatment provision, and teaching/activities of daily living at admission and discharge. Smaller and usually nonsignificant correlations were observed in activities that did not involve direct patient contact. Contact times increased exponentially as disability increased. Conclusions: These results support the construct validity of the FIM by demonstrating strong relationships (r values in the range of .40 to .60) between burden of care and a measure of disability.