cssi/SciSciGPT-SciSciNet huggingface dataset:
Increasing cardiopulmonary resuscitation between countershocks during use of automated external defibrillators in out-of-hospital cardiac arrest

Study objectives: Prompt cardiopulmonary resuscitation (CPR) and electrical defibrillation are the most important determinants of successful resuscitation in out-of-hospital ventricular fibrillation cardiac arrest (OHCA). Evidence supports that increasing the balance of "hands-on" CPR compared with "hands-off" CPR may improve survival in OHCA. We assess whether emergency medical technician training and automated external defibrillator (AED) reconfiguration are associated with an increase in the amount of CPR delivered between countershocks. Methods: The study was a cohort study of 301 persons who experienced OHCA and were treated with at least 2 AED countershocks by the emergency medical services (EMS) first-tier responders in the study community. In January 2003, first-tier EMS providers were retrained as to the importance of hands-on CPR between countershocks. In addition, a subset of AEDs (models using biphasic waveform) was reconfigured to remove continuous fibrillation detection and its associated voice prompts for the first 2 minutes after the each defibrillatory shock to be comparable with the other AED models. AED electronic recordings and EMS reports were reviewed to assess the amount of CPR. The main outcome was the density of CPR assessed as the time spent performing hands-on CPR divided by the total time between the first and second countershock. The density of CPR was compared for the cohort of cases before and after the training and reconfiguration intervention. Results: Two hundred sixty-one cases were treated in the preintervention period and 40 in the postintervention period. CPR density was 0.42±0.20 in the preintervention period compared with 0.50±0.17 in the postintervention period ( P =.03). The difference in CPR density was greatest for the biphasic waveform AED for which EMS was retrained and the AED reconfigured (0.35±0.21 versus 0.51±0.16, P =.001). There was a smaller increase for the other AED models for which EMS was retrained, but no reconfiguration was necessary (0.43±0.19 versus 0.50±0.18, P =.30). Survival to hospital discharge was 24.5% for the preintervention period compared with 26.3% in the postintervention period ( P =.81). Among patients treated with biphasic waveform AEDs, survival to hospital discharge was 16.7% in the preintervention period compared with 25.9% for the postintervention period ( P =.30). Conclusion: Training interventions and AED reconfiguration may increase the proportion of time spent performing hands-on CPR between countershocks in ventricular fibrillation cardiac arrest. Whether this increase improves outcomes including survival requires additional study.
GC/IR Optimal Design, A Comprehensive Study

A theoretical model for the optimum optical design of lightpipe GC/FT-IR systems was developed. This model predicts the optimum optical design based on the maximum spectral signal-to-noise (S/N) for a given lightpipe size. Experimental measurements were made to confirm the accuracy of this model and a GC/FT-IR system based on this model was built and tested.
GPS profiling of the lower troposphere from space: Inversion and demodulation of the open-loop radio occultation signals

[1] Global Positioning System (GPS) radio occultation (RO) is a space-borne remote sensing technique providing accurate, all-weather, high vertical resolution atmospheric parameters, including pressure, temperature and humidity in the troposphere and stratosphere. In the moist lower troposphere (LT) RO encounters known problem related to the phase-locked loop (PLL) tracking technique applied in standard GPS receivers and the complicated structure of LT RO signals. This problem has been overcome by developing an open-loop (OL) tracking technique. This paper outlines post-processing of OL RO data. In order to invert OL RO signals, the GPS navigation data modulation (NDM) has to be removed in post-processing. This paper demonstrates that some tropical occultations are not accurately inverted (associated refractivity inversion errors exceed 5%) without the use of externally supplied NDM bit sequences. This result has important implications for the use of RO data from future RO missions for climate research and weather forecasting.
Numerical study of ductile failure morphology in solder joints under fast loading conditions

Abstract A numerical study is undertaken to investigate solder joint failure under fast loading conditions. The finite element model assumes a lap-shear testing configuration, where the solder joint is bonded to two copper substrates. A progressive ductile damage model is incorporated into the rate-dependent elastic-viscoplastic response of the tin (Sn)–silver (Ag)–copper (Cu) solder alloy, resulting in the capability of simulating damage evolution leading to eventual failure through crack formation. Attention is devoted to deformation under relative high strain rates (1–100 s−1), mimicking those frequently encountered in drop and impact loading of the solder points. The effects of applied strain rate and loading mode on the overall ductility and failure pattern are specifically investigated. It is found that, under shear loading, the solder joint can actually become more ductile as the applied strain rate increases, which is due to the alteration of the crack path. Failure of the solder is very sensitive to the deformation mode, with a superimposed tension or compression on shear easily changing the crack path and tending to reduce the solder joint ductility.
Nuclear charge-exchange corrections to leptonic pion production in the (3, 3)-resonance region

We discuss nuclear charge-exchange corrections to leptonic pion production in the region of the (3, 3) resonance, both from a phenomenological viewpoint and from the evaluation of a detailed model for pion multiple scattering in the target nucleus. Using our analysis, we estimate the nuclear corrections needed to extract the ratio $R=\frac{[\ensuremath{\sigma}({\ensuremath{\nu}}_{\ensuremath{\mu}}+n\ensuremath{\rightarrow}{\ensuremath{\nu}}_{\ensuremath{\mu}}+n+{\ensuremath{\pi}}^{0})+\ensuremath{\sigma}({\ensuremath{\nu}}_{\ensuremath{\mu}}+p\ensuremath{\rightarrow}{\ensuremath{\nu}}_{\ensuremath{\mu}}+p+{\ensuremath{\pi}}^{0})]}{2\ensuremath{\sigma}({\ensuremath{\nu}}_{\ensuremath{\mu}}+n\ensuremath{\rightarrow}{\ensuremath{\mu}}^{\ensuremath{-}}+p+{\ensuremath{\pi}}^{0})}$ from neutral-current search experiments using $_{13}\mathrm{Al}^{27}$ and other nuclei as targets.
Fluctuations of the runaway electron flux to the PLT tokamak limiter

Abstract The flux of runaway electrons into the PLT limiter is modulated at frequencies up to 200 kHz with a power spectrum similar to that of density fluctuations observed by microwave scattering.
Delirium in hospitalized older persons: outcomes and predictors.

The purpose of this study was fourfold: to determine the rate of delirium among hospitalized older persons, to contrast the clinical outcomes of patients with and without delirium, to identify clinical predictors of delirium, and to validate the predictive model in an independent sample of patients.
Asymptotic solution of the unsteady boundary layer equations

An extension of the Meksyn asymptotic method to unsteady boundary layers in laminar, incompressible flow is investigated. The results indicate that unsteady boundary layers can be calculated by the Meksyn asymptotic method with comparable accuracy to that obtained for steady flows. Several differences from the well developed steady-flow application exist and require further work before general problems can be treated. The calculation technique is more straight-forward for cases involving acceleration because three or four terms in the expansions may then yield sufficient accuracy. The form of the governing equation required by the Meksyn method indicates that it is most useful for unsteady stagnation boundary layers since some basic unsteady flows are not directly accessible in their simplest form from that equation. The effect of unsteadiness on the rate of asymptotic convergence is assessed by detailed comparison of a similar solution for unsteady, stagnation flow with analogous results from the Falkner-Skan equation and of reliable numerical results for both cases.
Effect of sex-stereotyping in evaluating males in a traditional female role.

To investigate the possible presence of reverse sex-stereotyping with respect to males in an occupation traditionally associated with females, 135 senior female nursing students were asked to rate the value of an article The author's sex and credentials were manipulated and the resultant ratings were analyzed. Results indicate that some reverse sex-stereotyping occurred. This and other findings are presented and directions for future research discussed.
Assessing Climate Change

Large-scale climatic patterns, rather than a growing “heat island” effect, are the overriding influence on weather in the Potomac River area, and temperature data in the area can therefore be validly compared to global trends. At least temporarily, however, the area, which includes Washington, D.C., has lost its coupling with global temperature trends. Short-term regional anomalies in the Potomac River area's weather, especially high summer temperatures, may promote legislative action in the U.S. Congress on long-term global climate research. However, the current benign weather conditions in the political center of the United States tend to divert attention away from global climate research, diminishing the likelihood of significant expansion of research funding and greenhouse gas legislation.
SHIFTING THROUGH TIME: OYSTERS AND SHELL RINGS IN PAST AND PRESENT SOUTHEASTERN ESTUARIES

ABSTRACT Oysters and oyster reefs are important components in the rich and productive southeastern US marsh-estnarine ecosystems. In recent decades, ecological research has shown that these complex systems can be driven by external biotic and abiotic perturbations or internal system dynamics that cause the system to rapidly reorganize into another alternate state or regime. Such shifts may have happened on a much larger scale several thousand years ago along the southeastern coast of North America. Beginning about 4,500 B.P., the coastal Native Americans built complex structures or oyster shell rings on the landward side of the southeastern sea islands of South Carolina, Georgia, and Florida. The construction of shell rings is believed to symbolize the conversion of nomadic hunter-gatherers to coastal fisherfolk and is considered a pivotal stage in the evolution of preEuropean contact culture in the United States. But, by about 3000 B.P., the shell rings were abandoned and the Native Americans dispersed. ...
Internal Wave Breaking at Concave and Convex Continental Slopes

Abstract Internal wave reflection from a sloping topographic boundary may lead to enhanced shear if the topographic angle to the horizontal is close to that of the internal wave group velocity vector. Previous analytic studies have suggested that shear enhancement is reduced at concave slopes as compared with convex and planar slopes near the critical angle. Here the internal wave reflection from concave and convex slopes that pass through the critical angle is investigated numerically using the nonhydrostatic Massachusetts Institute of Technology General Circulation Model (MITgcm). Overturning, shear instability, and resultant mixing are examined. Results are compared with simulations of wave reflection from planar slopes with angles greater than, less than, and equal to the critical angle. In contrast to the analytic predictions, no reduction in mixing is found for the concave slope as compared with the other slopes. In all cases, stratification is eroded in a band above the slope, bounded at its outer ...
Use of fluorescence-activated cell sorter to isolate mutant mammalian cells deficient in an internal protein, dihydrofolate reductase

Dihydrofolate reductase-deficient mutants of Chinese hamster ovary cells have been selected based on their inability to bind a fluorescent derivative of methotrexate, a substrate analog. Nonfluorescent mutant cells were isolated from mutagenized populations using a fluorescence-activated cell sorter. After multiple rounds of sorting plus regrowth, the mutant cell frequency was increased from an initial 10−5 to greater than 0.9. This use of the cell sorter to isolate mutants deficient in an internal protein should be applicable to any gene product that is able to bind a fluorescent ligand tightly. The method has the advantage of allowing the screening of large numbers of cells and of selecting for partially expressed phenotypes.
Effects of clozapine and 2,5-dimethoxy-4-methylamphetamine [DOM] on 5-HT2A receptor expression in discrete brain areas

Activation of 5-HT2A receptors has been shown to be an essential component of the discriminative stimulus effects of indoleamine and phenethylamine hallucinogens. The objective of the present study was to determine the neuroanatomical location of the 5HT2A receptors which may be responsible for the stimulus effects of the phenethylamine hallucinogen [−]2,5-dimethoxy-4-methylamphetamine (DOM). It was hypothesized that brain areas containing altered 5-HT2A receptor expression in the context of a similar alteration in DOM-induced stimulus control might be important in mediating the stimulus effects of DOM. Fisher 344 rats were treated with either clozapine (25 mg/kg/day) or DOM (2 mg/kg/day) for 7 days, and the consequences of these drug treatment regimens on DOM-induced stimulus control and on 5-HT2A receptor expression in several brain areas were determined. Chronic administration of clozapine was associated with a wide-spread decrease in levels of 5-HT2A/2C receptors. Conversely, treatment with DOM had varied effects including a neuroanatomically selective decrease in 5-HT2A/2C receptor levels that was restricted to the olfactory nucleus. Both chronic treatment with DOM and clozapine decreased the stimulus effects of DOM. The present findings suggest a role for the olfactory nucleus in producing the stimulus effects of DOM.
OCCURRENCE OF CENTRIOLES DURING SKELETAL AND CARDIAC MYOGENESIS

Skeletal muscle development of vertebrates is characterized by the formation of multinuclear muscle fibers through the fusion of uninucleate myoblasts (Holtzer et al ., 1958; Capers, 1960 ; Konigsberg et al ., 1960 ; Zhinkin and Andreeva, 1963 ; Mintz and Baker, 1967) . The myogenic cells constitute a line of mitotically dividing elements which serve as the basis for the initiation of skeletal muscle development in the early embryo (Stockdale and Holtzer, 1961) and for the increase in nuclear number of myotubes and muscle fibers before and after birth (MacConnachie et al ., 1964) . This stem line has been postulated to remain in the growing and adult organism as the "satellite" cell (Mauro, 1961 ;
A four-stage factor analytic approach to studying behavioral domains

Four stages in factor analyzing behavioral do mains are outlined using a measure of mental well- being or self-actualization, the Personal Orientation Inventory (POI), as an example. The stages are...
Electrical synapses between Gaba-Releasing interneurons

Although gap junctions were first demonstrated in the mammalian brain about 30 years ago, the distribution and role of electrical synapses have remained elusive. A series of recent reports has demonstrated that inhibitory interneurons in the cerebral cortex, thalamus, striatum and cerebellum are extensively interconnected by electrical synapses. Investigators have used paired recordings to reveal directly the presence of electrical synapses among identified cell types. These studies indicate that electrical coupling is a fundamental feature of local inhibitory circuits and suggest that electrical synapses define functionally diverse networks of GABA-releasing interneurons. Here, we discuss these results, their possible functional significance and the insights into neuronal circuit organization that have emerged from them.
Performance analysis and design of a logic simulation machine

The high costs associated with logic simulation of large VLSI circuits has led to the need for new computer architectures tailored to the simulation task. Such architectures have the potential for significant speed-ups over software-based logic simulators executing on standard sequential computers. This paper presents a model of one class of multiprocessor simulation architectures and compares the performance of some of these machines using data obtained from simulations of VLSI circuits. In addition, we discuss the implications of our results on machine design and examine the sensitivity of the model to variations in circuit characteristics.
A high yield synthesis of 13C- and 14C-labeled diethyl carbonate

Labeled silver carbonate was prepared from barium carbonate-13C or -14C and aqueous silver nitrate in 95 to 100% yield. Diethyl carbonate-13C or -14C was generated in 60 to 85% overall yield by treatment of labeled silver carbonate with ethyl iodide and tetraethylammonium iodide in dimethylformamide. The effects of alterations in reaction time, metal ion, solvent and catalyst were investigated.
Effects of water stress on the activities of three enzymes in maize seedlings.

Changes in the activities of three enzymes (nitrate reductase, l-phenylalanine ammonia-lyase, and a dehydronicotinamide adenine dinucleotide-oxidase complex) were measured during development of water stress in young maize (Zea mays) plants.l-Phenylalanine ammonia-lyase and nitrate reductase activities decreased markedly with water deficits of 10 to 20%. The activities did not reach zero at water deficits as high as 50%, but appeared to approach a new steady state. Partial to complete recovery of enzyme activity occurred 24 hours after rehydration of the stressed plants. The oxidase activity did not respond to water stress in the same manner as that of the other two enzymes.It is suggested that the level of enzyme activity is a consequence of an equilibrium between the rates of synthesis and degradation, and that progressive tissue dehydration reduces both the enzyme synthesis and the enzyme-inactivating systems.
XXIII.—Descriptions and records of bees.—CLXVII

(1938). XXIII.—Descriptions and records of bees.—CLXVII. Annals and Magazine of Natural History: Vol. 1, No. 2, pp. 223-230.
T‐Cell lymphoma cell lines (HUT102 and HUT78) established at the National Cancer Institute: History and importance to understanding the biology, clinical features, and therapy of cutaneous T‐cell lymphomas (CTCL) and adult T‐cell leukemia‐lymphomas (ATLL)

Efforts at the National Cancer Institute to generate continuous in vitro cultures from patients with mycosis fungoides and the Sezary syndrome, neoplasms with a mature T-helper phenotype, led to the establishment of two cell lines, HUT78 and HUT102. Further characterization of these cell lines led to the identification of the first human retrovirus, HTLV-1, in the HUT102 cells, and the clinical description of the syndrome of HTLV-1 associated acute T-cell leukemia/lymphoma; the serum antibody test to screen for this virus was developed from the serum of the patient from whom the cell line was derived. The HUT78 cell line was pivotal in the identification and characterization of the HIV retrovirus in that a subclone, H9, proved to be permissive for replication of HIV in vitro. Propagation of HIV in vitro in H9 cells allowed for the development of immunological reagents to screen blood supplies for the presence of the virus. Further biologic and molecular studies of these lines have led not only to a better understanding of the underlying diseases but also to the development of rational therapeutic approaches.
An Overview of Marriage Enrichment

This article acts as an introduction to the new regular section in The Family Journal called Marriage Education and Enrichment. A brief overview of the history of marriage enrichment is followed by summaries and research associated with five of the leading marriage enrichment programs and research (ACME, TIME, Relationship Enhancement, PREPARE/ENRICH, and PREP). Participants’ views of outcomes and future directions for marriage enrichment are discussed.
Iron sulfate supplementation decreases zinc protoporphyrin to heme ratio in premature infants.

Objectives To test the utility of zinc protoporphyrin to heme ratio (ZnPP/H) as an indicator of iron status in premature infants and to evaluate the effect of oral iron supplements on oxidative injury. We hypothesized that iron sulfate supplementation would decrease the ZnPP/H in preterm infants. Study design Infants eligible for this prospective study were: hospitalized, 24 to 32 weeks of gestation, 7 to 60 days old, feeding ≥ 70mL/kg/d, with a ZnPP/H ≥ the mean for age. Iron dose was determined by the ZnPP/H. Iron status and oxidative injury were evaluated at study entry and completion. Concurrent control subjects met entry criteria but were not enrolled and were not treated with iron during the study interval. Statistical evaluation included repeated measures analysis of variance and Z-score conversions. Results Entry ZnPP/H of iron-treated subjects (n = 16) and control subjects (n = 16) were not different. The ZnPP/H of iron-treated infants was lower at study end (P Conclusions Iron sulfate supplementation (3-12 mg/kg/d) decreases ZnPP/H, is tolerated, and is not associated with increased oxidative injury.
Early experiences co-scheduling work and communication tasks for hybrid MPI+X applications

Advances in node-level architecture and interconnect technology needed to reach extreme scale necessitate a reevaluation of long-standing models of computation, in particular bulk synchronous processing. The end of Dennard-scaling and subsequent increases in CPU core counts each successive generation of general purpose processor has made the ability to leverage parallelism for communication an increasingly critical aspect for future extreme-scale application performance. But the use of massive multithreading in combination with MPI is an open research area, with many proposed approaches requiring code changes that can be unfeasible for important large legacy applications already written in MPI. This paper covers the design and initial evaluation of an extension of a massive multithreading runtime system supporting dynamic parallelism to interface with MPI to handle fine-grain parallel communication and communication-computation overlap. Our initial evaluation of the approach uses the ubiquitous stencil computation, in three dimensions, with the halo exchange as the driving example that has a demonstrated tie to real code bases. The preliminary results suggest that even for a very well-studied and balanced workload and message exchange pattern, co-scheduling work and communication tasks is effective at significant levels of decomposition using up to 131,072 cores. Furthermore, we demonstrate useful communication-computation overlap when handling blocking send and receive calls, and show evidence suggesting that we can decrease the burstiness of network traffic, with a corresponding decrease in the rate of stalls (congestion) seen on the host link and network.
Heterodyne instrumentation at the CSO

The Caltech Submillimeter observatory (CSO) is one of the World's premier submillimeter telescopes. It consists of a 10.4 meter diameter Leighton radio dish situated in compact dome near the summit of Mauna Kea, Hawaii. The telescope has been operating under a contract from the National Science Foundation on a regular basis since 1988. For the first time heterodyne Superconducting-Insulating-Superconducting (SIS) receivers with a 1 GHz intermediate frequency (IF) are available for the entire 180 - 950 GHz Submillimeter band. To enhance the extra-galactic capabilities of the observatory and to allow interferometry with the upcoming Submillimeter Array (SMA) project, we are actively working towards upgrading all heterodyne instruments with a 3 GHz IF bandwidth. Concurrent to the planned IF upgrade, we are constructing a dual polarization beam switching 345 GHz extra-galactic receiver, also with a 3 GHz IF bandwidth. Ideally, this instrument will give the CSO a factor of 8 improvement in integration time over the current 345 GHz receiver, and will be ideally suited for the study of highly red-shifted extra-galactic sources.
Mutagenesis and mutant selection in Physarum polycephalum.

Physarum polycephalum myxamoebae were exposed to ultraviolet irradiation and plated in the absence and presence of caffeine. Caffeine reduces the shoulder on the UV1 dose-survival curve, thereby increasing the UV-sensitivity for survival. Caffeine alone is a moderate mutagen. Used in conjunction with UV a strong mutagenic action is observed. Active growth is required for both of these mutagenic actions.
The Patient With Coronary Artery Disease Scheduled for Noncardiac Surgery

Summary Cardiovascular morbidity continues to represent the single most important contributor to surgical mortality. The impact of postoperative interventions in potentially improving cardiovascular morbidity and mortality is extremely difficult to separate from the influence of the intra-operative technique. It is most likely that the combination of techniques used intra-operatively and postoperatively have a combined impact on cardiovascular outcome. A thorough preoperative assessment of the patient to determine the probability of risk for coronary artery disease and whether further workup will improve patient outcome is essential. Perioperative interventions such as coronary artery bypass grafting have not always shown a subsequent reduction in patient morbidity before noncardiac surgery. Other perioperative interventions such as percutaneous transluminal coronary angioplasty and the insertion of an intraaortic balloon pump may provide more patient benefit with less risk than coronary artery bypass graft. Intra-operative monitoring devices are only helpful if clinicians can interpret and extrapolate meaningful data that will assist them in achieving an end-point (detection and prevention of myocardial ischemia) for their patient's management. A familiarity of the sensitivity and specificity of a particular monitoring device is helpful to determine the best method for detecting myocardial ischemia. A smooth transition from the intraoperative to the postoperative period is desirable. Attenuation of the neurohumeral stress response through adequate pain management may reduce the incidence of postoperative morbid cardiac events. Regional techniques may hold the greatest promise for effecting significant improvements in cardiovascular outcome. Yeager's study is conclusive in showing that epidural anesthesia and analgesia results in decreased morbidity and mortality for major vascular surgery patients. Tuman 55 showed decreased hypercoagulability with epidural anesthesia that may be a critical physiological benefit in reducing the incidence of vascular graft occlusion, coronary artery occlusion, and deep venous thromboses. Blomberg's studies in patients with severe coronary artery disease provide insight into the mechanisms by which epidural anesthesia may be a therapeutic measure in preventing and treating myocardial ischemia. Perhaps we should consider using thoracic epidural anesthesia for patients with coronary artery disease scheduled for noncardiac surgery to reduce the incidence or even the occurrence of perioperative myocardial infarction. Perhaps thoracic epidural anesthesia will replace our conventional therapies for myocardial ischemia. Only further investigation of this hypothesis will elucidate the answer.
Merger Strategies and Capital Market Risk

The literature on corporate diversification suggests a relationship between the relatedness of merging firms and risk. We tested that notion by classifying 297 large mergers into four relatedness c...
Stimulation by Citric Acid of Germination of Eastern Red Cedar ( Juniperis virginiana L.)

I HAVE found that pretreatment with citric acid increases both speed and total germination of eastern red cedar seed. Earlier, exploratory investigations showed that the acid also increased both speed and total germination of bald cypress seed (Taxodium distichum (L.) Rich) and I have reported similar effects of pretreatment of eastern white pine seed (Pinus strobus L.) with both citric and tartaric acids1. Of the several species examined, eastern red cedar showed the most striking response to pretreatment with citric acid.
An Exploration of Accountants, Accounting Work, and Creativity

ABSTRACT: In two studies, we explore whether creativity is essential—or antithetical—to professional accounting work. In Study 1, archival analysis of U.S. Department of Labor data indicates that: (1) professional accounting work requires no less creativity than do three competing professions and a diverse sample of U.S. occupations, and (2) greater creativity may be required in financial than in auditing and taxation accounting work. In Study 2, a survey contrasts the self-assessed and number-of-uses creativity of governmental accounting professionals and Master’s of Accountancy (M.Acc.) students with that of M.B.A. students. Results indicate lower creativity among accountants and M.Acc. students compared with M.B.A. students, and no systematic relationship between ethics and creativity. We conclude that while creativity matters to accounting work—more to some areas of accounting practice than others—accountancy education and work may attract or reward entrants with less than desirable levels of creativi...
The effects of the invasive Argentine ant (Linepithema humile) and the native ant Prenolepis imparis on the structure of insect herbivore communities on willow trees (Salix lasiolepis)

We examined the relative effects of the invasive Argentine ant, Linepithema humile , and a common native ant, Prenolepis imparis , on the community of herbivorous insects occurring on willow trees, Salix lasiolepis in Northern California, U.S.A. 2. Using paired control and treatment branches from which we excluded ants and other non-volant predators, we found that effects of Argentine ants on the herbivore community were generally similar to those of P. imparis . Argentine ants and P. imparis suppressed the damage by skeletonising insects by 50%, but had little effect on most other external-feeding or internal-feeding guilds. 3. The abundance of aphids was 100% greater in the presence of Argentine ants, but there was no effect on aphid numbers in the presence of P. imparis . Late season aphid numbers were substantially higher in the presence of Argentine ants, but not P. imparis . 4. The effects of Argentine ants on skeletonising insects and aphids combined with the overwhelming abundance of Argentine ant workers, suggests that they may have substantial, but often overlooked, effects on the herbivore communities on other plant species in or near riparian habitats in which they invade.
Which is more cost-effective under the MELD system: primary liver transplantation, or salvage transplantation after hepatic resection or after loco-regional therapy for hepatocellular carcinoma within Milan criteria?

hpb_355 783..791 Objective: The optimal strategy for treating hepatocellular carcinoma (HCC), a disease with increasing incidence, in patients with Child–Pugh class A cirrhosis has long been debated. This study evaluated the cost-effectiveness of hepatic resection (HR) or locoregional therapy (LRT) followed by salvage orthotopic liver transplantation (SOLT) vs. that of primary orthotopic liver transplantation (POLT) for HCC within the Milan Criteria. Methods: A Markov-based decision analytic model simulated outcomes, expressed in costs and quality-adjusted life years (QALYs), for the three treatment strategies. Baseline parameters were determined from a literature review. Sensitivity analyses tested model strength and parameter variability. Results: Both HR and LRT followed by SOLT were associated with earlier recurrence, decreased survival, increased costs and decreased quality of life (QoL), whereas POLT resulted in decreased recurrence, increased survival, decreased costs and increased QoL. Specifically, HR/SOLT yielded 3.1 QALYs (at US$96 000/QALY) and LRT/SOLT yielded 3.9 QALYs (at US$74 000/QALY), whereas POLT yielded 5.5 QALYs (at US$52 000/QALY). Sensitivity analyses supported these findings at clinically meaningful probabilities. Conclusions: Under the Model for End-stage Liver Disease (MELD) system, in patients with HCC within the Milan Criteria, POLT increases survival and QoL at decreased costs compared with HR or LRT followed by SOLT. Therefore, POLT is the most cost-effective strategy for the treatment of HCC.
Double Jeopardy How Soluble P-Selectin Activates Leukocytes in Peripheral Arterial Occlusive Disease

See related article, pages 149–156 In this issue of Circulation Research , Woollard et al identify a critical role of pathologically elevated levels of soluble P-selectin (sP-selectin) found in the plasma of patients with peripheral arterial occlusive disease (PAOD) that promotes the activation of neutrophils and induces their adhesion to fibrinogen and platelet monolayers.1 P-selectin is an inflammatory adhesion molecule expressed on activated platelets and endothelial cells.2 During the last two decades, the role of inflammatory cells and adhesion molecules in the development and progression of vascular diseases has become apparent, and it is now recognized that many of the cellular and molecular events that underlie atherosclerotic vascular disease are inflammatory in nature.3,4 One manifestation of atherosclerosis is PAOD, which is characterized by intermittent claudication and critical limb ischemia.5 The first case of intermittent claudication caused by arterial occlusive disease was described as early as 1831 by Jean Bouley, and a few years later Heinrich Erb proposed walking as a therapy for intermittent claudication6; however, the precise mechanism of development of PAOD as well as the optimal treatments of this disease still remain to be determined. Numerous studies have identified soluble inflammatory markers including acute phase proteins and adhesion molecules as risk factors for cardiovascular disease, but it is unclear whether they play causative roles as active participants in the initiation and maintenance of the inflammation (mediators) or whether they merely indicate the existence of the disease (markers). Soluble P-selectin is elevated in patients with vascular disorders such as hypertension,7 hypercholesterolaemia, …
Chemistry of gap junctions.

Gap junctions [also called nexus (15) or maculae communicantes (102)] repre­ sent transcellular channels that permit the exchange of small molecules and ions between neighboring cells (28, 33, 74, 75, 82, 86, 89, 103). They differ from other membrane channels in a number of respects: they provide a pathway between cells rather than across one cell membrane; they are nonspecific; and they allow for passive diffusion. Gap junctions link cells to their neighbors in almost every organ of the body (31) and are essentially ubiquitous in the animal kingdom; they can be recognized in many systems by their very characteristic morphology. In thin sections they are seen as paired parallel plasma mem­ branes of unusually smooth outline, separated from each other by a narrow space of constant width (94, 97), the "gap." In freeze-cleaved (39, 55)[or negatively stained (35)] specimens, patches of closely packed membrane particles (the connexons) (41) in one membrane are in register with similar structures in the membrane of the apposed cell (10). Each connexon presum­ ably consists of protein subunits arranged so as to form a channel (9, 101, 112). From a physiological standpoint they allow for electrical coupling or exchange of molecules up to 800-1200 daltons (28-30, 86, 103). Permeability of the junction can usually be modulated by changes in pH (105, 111), pC02 (110), pCa (83, 98, 99), or membrane potential (46, 104). It is the purpose of this paper to review what is known about the chemistry of these proteins and to analyze our understanding of the relationship between their structure and the overall organization and physiology of gap junctions [recent reviews are found
Information transfer by energy-efficient neurons

We introduce and analyze a biologically motivated mathematical model of a neuron in primary cortex that we call neuron j, or just j. Our goal is to ascertain how j maximizes the ratio of the information it conveys to the energy it expends.
Aggregation for the probabilistic traveling salesman problem

In the probabilistic traveling salesman problem (PTSP), customers require a visit with a given probability, and the best solution is the tour through all customers with the lowest expected final tour cost. The PTSP is an important problem, both operationally and strategically, but is quite difficult to solve with realistically sized problem instances. One alternative is to aggregate customers into regions and solve the PTSP on the reduced problem. This approach raises questions such as how to best divide customers into regions and what scale is necessary to represent the full objective. This paper addresses these questions and presents computational results from experiments with both uniformly distributed and clustered data sets. The focus is on large problem instances where customers have a low probability of requiring a visit and the CPU time available is quite limited. For this class of instances, aggregation can yield very tight estimates of the full objective very quickly, and solving an aggregated form of the problem first can often lead to full solutions with lower expected costs.
Effect of dry period overconditioning on subsequent metabolic disorders and performance of dairy cows.

Abstract In two trials with 44 cows over an 8-wk dry period, control cows were fed alfalfa forage and minimal grain compared to liberal grain plus corn silage (Trial 1) or plus alfalfa forage (Trial 2). Following parturition all cows were fed to meet requirements. In trial 2 half of each group received nicotinic acid at approximately 12g daily for 8 wk, starting on the 8th day postpartum. In Trial 1 overconditioned exceeded control in prepartum insulin 41.4 to 23.5 μU/ml, free fatty acids of plasma 1 wk postpartum 23.9 to 19.0 mg/100ml and 2 to 4 wk postpartum 16.3 to 12.1 mg/100ml, body weight gain during the dry period 77.1 to 38.5kg. In Trial 2 overconditioned exceeded control only in intake of digestible energy during the dry period 42.9 to 38.1 Meal/day and postpartum 64.1 to 62.3 Meal/day along with milk protein 3.39 to 3.20%. Cows fed nicotinic acid showed an advantage over controls in body weight change +1.41 to −3.75 kg/wk, digestible energy intake 64.1 to 62.2 Meal/day, and cholesterol of plasma 175 to 204 mg/100ml. Liver biopsies 2 days postcalving in overconditioned compared to controls showed total lipids 12.5 to 9.8%, triglycerides 67.3 to 30.5 mg/g, phospholipids 19.8 to 27.7 mg/g, and triglyceride: phospholipid ratio 3.4 to 1.1. Total cases of periparturient diseases of combined trials were 31 overconditioned and 21 control during the first 11 wk postpartum.
SOCIAL AND BIOPHYSICAL CORRELATES OF CHANGE IN FOREST LANDSCAPES OF THE INTERIOR COLUMBIA BASIN, USA

Understanding multi-scale interactions among human activities and biophysical factors in ecosystem dynamics is a critical step toward managing for long-term ecological integrity. Studying variation and change over multiple spatial and temporal scales (100–100 000 ha and 1–500 yr) allows one to tease apart the relative roles of these factors. Using meso-scale data predominantly from the recent Interior Columbia River Basin Ecosystem Management Project (ICBEMP), we assessed the role of several economic, demographic, cultural, climatic, topographic, and geologic factors in forest spatial pattern changes (from the 1930s to the 1990s) across 800 000 km2 of the interior Northwest, USA. Our 228 forested subwatersheds (∼10 000 ha) lie in 76 counties in six states. We identified key correlates of change, their hierarchical scale, and the scale of vegetation classification at which these correlates explained most change. We used general linear models and partial multiple regression analysis, supplemented by logisti...
A high‐resolution pore water sampler for sandy sediments

In this paper, we present a new technique for collecting pore-water samples in coarse- to fine-grained sandy sediments. We have used the technique both for in situ sampling and for pore-water extraction from sediment cores brought back to the laboratory, in both cases with a depth resolution as fine as 1 cm. The key device is a long, thin (∼2 mm) stainless steel tube with a specially designed tip that functions as a filter. Pore-water samples are collected by inserting the tube into the sediment at the desired depth and applying a light suction from a syringe connected to the tube. The sample is injected immediately into a vial through a syringe filter and stored for later analysis. The technique has some clear advantages over other methods that are used commonly in sandy sediments. In comparison with lysimeters or sippers, it gives pore-water samples with a much higher depth resolution, which often is needed to accurately estimate fluxes across the sediment-water interface or transformation rates of solutes within the sediments. In comparison with dialysis cells or peepers, the new technique gives measurements that truly represent the time of collection. This can be crucial when non-steady-state systems are studied. Furthermore, disturbance of the sediment is minimal because of the small dimension of the tube. This is especially important in vegetated sediments, in which the deployment of larger conventional samplers is likely to cause significant disturbance. Finally, sample extraction is less laborious than other techniques, requiring only one site visit and typically < 1 min of sampling time per sample. In laboratory tests using a dye tracer, we showed that pore water was drawn evenly toward the tube tip from all directions in the surrounding sediment. On the basis of these results, we provide guidelines for choosing the appropriate sampling depth intervals as a function of the sample size. Data from representative pore-water profiles are presented for PO 4 3- from vegetated coarse-grained carbonate sediments in the Bahamas and NH 4 + from fine-grained unvegetated sands in a temperate coastal lagoon in Virginia.
Diet-induced obesity and hepatic gene expression alterations in C57BL/6J and ICAM-1-deficient mice.

The effects of high-fat feeding on the development of obesity were evaluated in intercellular adhesion molecule-1 (ICAM-1) knockout and C57BL/6J (B6) male mice fed a high-fat diet for ≤50 days. Ser...
A Matlab-based teaching of the two-stub smith chart application for electromagnetics class

This paper specifically presents a Matlab-based teaching approach to the two-stub Smith chart problem that is typically covered in an undergraduate course on electromagnetic fields. Matlab provides a powerful computation and display platform by means of which fundamental and advanced concepts relating to transmission lines can be understood and implemented. The paper restates the solving techniques of a two-stub Smith chart problem in terms of a process consisting of steps. These steps can be implemented as modules written in Matlab scripts. This modular approach using Matlab enhances the studentspsila understanding of the Smith chart technique as a solution process with the specific objectives of each module clearly identified. Furthermore, the computations are more accurate and the results can be displayed and interpreted in a more effective manner. The students taking the course completed an on-line survey to rate the effectiveness of the Matlab tool in solving the two-stub transmission line problem. The responses to the survey reaffirmed the belief that solutions to problems involving concepts that can be challenging to grasp are learned more effectively when the steps of the solution are associated with processing modules comprising clearly defined input-output relationships.
Proton MR spectroscopic imaging of rhesus macaque brain in vivo at 7T

Insights into the pathogenesis of neurological disorders and the subsequent development of therapies for them may require preclinical trials in nonhuman primates whose brain anatomy, cellular composition, biochemistry, and physiology is similar to their human counterpart. Indeed, such models are used to study Parkinson's and Huntington's diseases (1,2), ischemic stroke (3), and neuroAIDS (4,5) among others. These models have shown similar metabolic changes to those in analogous regions of the human brain, making their use critical to our understanding of basic disease mechanisms and response to therapy. Such models may be particularly suitable to test therapeutic strategies using stem cell transplantation, trophic factors, and gene therapy (3,6). Compared with smaller animals, however, the cost and complexity of experiments in nonhuman primates severely restrict the number that can be used. Serial studies, therefore, favor nondestructive methods, such as MRI and proton MR spectroscopy/spectroscopic imaging (1H-MRS/MRSI). The latter modality allows assessment of neuronal cells, cell energetics, membrane turnover, gliosis, and glycolysis through their respective surrogate markers, N-acetylaspartate (NAA) (7), creatine (Cr) (8), choline (Cho), myo-inositol (mI), and lactate levels (9). Furthermore, since in vivo 1H-MRS has shown variable metabolic changes among different brain regions, 3D MRSI variants are clearly the technology of choice (10,11). These constraints combined with the much smaller primate brain require proportionally higher spatial resolution than the 1−8 cm3 common in humans (12,13) in order to resolve several analogous structures in the same scan. Additionally, they should be short enough to complete all the tests on an unharmed anesthetized animal. In this study, we report for the first time a 3D multi-voxel 1H-MRSI at 0.05 cm3 spatial resolution over ≈25% of the rhesus macaque brain with a 25-min acquisition time at 7T. The goal is to demonstrate that the above points are addressable with current state-of-the-art hardware, technology, and techniques.
Local methods for estimating pagerank values

The Google search engine uses a method called PageRank, together with term-based and other ranking techniques, to order search results returned to the user. PageRank uses link analysis to assign a global importance score to each web page. The PageRank scores of all the pages are usually determined off-line in a large-scale computation on the entire hyperlink graph of the web, and several recent studies have focused on improving the efficiency of this computation, which may require multiple hours on a workstation.However, in some scenarios, such as online analysis of link evolution and mining of large web archives such as the Internet Archive, it may be desirable to quickly approximate or update the PageRanks of individual nodes without performing a large-scale computation on the entire graph. We address this problem by studying several methods for efficiently estimating the PageRank score of a particular web page using only a small subgraph of the entire web. In our model, we assume that the graph is accessible remotely via a link database (such as the AltaVista Connectivity Server) or is stored in a relational database that performs lookups on disks to retrieve node and connectivity information. We show that a reasonable estimate of the PageRank value of a node is possible in most cases by retrieving only a moderate number of nodes in the local neighborhood of the node.