cssi/SciSciGPT-SciSciNet huggingface dataset:
32P as an adjunct to standard therapy for locally advanced unresectable pancreatic cancer: a randomized trial.

This prospective randomized trial was undertaken to determine the added efficacy of 32P in treating locally advanced unresectable pancreatic cancer. Thirty patients with biopsy proven locally advanced unresectable adenocarcinoma of the pancreas were assessable after receiving 5-fluorouracil and radiation therapy with or without 32P, followed by gemcitabine. Intratumoral 32P dose was determined by tumor size and volume and was administered at months 0, 1, 2, 6, 7, and 8. Tumor cross-sectional area and liquefaction were determined at intervals by computed tomography scan. Tumor liquefaction occurred in 78% of patients receiving 32P and in 8% of patients not receiving 32P, although tumor cross-sectional area did not decrease. Serious adverse events occurred more often per patient for patients receiving 32P (4.2 ± 3.1 vs. 1.8 ± 1.9; p = 0.03) leading to more hospitalizations. Death was because of disease progression (23 patients), gastrointenstinal hemorrhage (4 patients), and stroke (1 patient). One patient not receiving 32P and one receiving 32P are alive at 28 and 13 months, respectively. 32P did not prolong survival (7.4 ± 5.5 months with 32P vs. 11.5 ± 8.0 months without 32P, p = 0.16). 32P promoted tumor liquefaction, but did not decrease tumor size. Intratumoral 32P was associated with more serious adverse events and did not improve survival for locally advanced unresectable pancreatic cancer.
C-Methyl-Flavanones as Farina on the Fronds of Pityrogramma pallida

Summary Pityrogramma pallida , an endemic silver fern of California, is characterised by very rich production of a white farinose exudate on its fronds. Such material normally consists of methoxy-flavonoids, occuring as aglycones. The present fern, however, produces C-methylated flavonoids. It can be shown that the major constituent of the farina is strobopinin, followed by desmethoxymatteucinol and cryptostrobin in decreasing quantities.
Fokker-Planck equation for particle growth by monomer attachment.

The population balance equation (PBE) for growth by attachment of a monomeric unit is described in the discrete domain by an infinite set of differential equations. Transforming the discrete problem into the continuous domain produces a series expansion which is usually truncated past the first term. We study the effect of this truncation and we show that by including the second-order term one obtains a Fokker-Planck approximation of the continuous PBE whose first and second moments are exact. We use this truncation to study the asymptotic behavior of the variance of the size distribution with growth rate that is a power-law function of the particle mass with exponent $a$. We obtain analytic expressions for the variance and show that its asymptotic behavior is different in the regimes $al1∕2$ and $ag1∕2$. These conclusions are corroborated by Monte Carlo simulations.
Measurement of voltage ratio at audio frequencies

HIGH orders of accuracy in voltage-ratio measurements are becoming increasingly important in computer fields. Accuracies of 0.01% or better are desired. Equipment such as precision ratio transformers are used in these applications. However, methods have been lacking for verifying the ratios of this equipment to that accuracy at the desired frequencies of 100 to 10,000 cps (cycles per second).
Frequency-domain on-off accumulative transmission over frequency-selective fading channels

In this paper, we propose a new cross-layer technique that utilizes frequency-domain on-off accumulative transmission (OOAT) in the physical layer to achieve collision-tolerance in the media access control (MAC) layer. The frequency-domain OOAT is developed for wideband systems operating in frequency-selective fading channels. The available spectrum is divided into a large number of orthogonal non-overlapping sub-channels. To achieve collision tolerance, each symbol is transmitted over a set of randomly chosen sub-channels to reduce the probability of collision. Spreading the signal over the frequency-domain also enables frequency diversity, and further improves system performance. Performance of the proposed scheme is analyzed and a performance bound, matched filter bound, is derived. Simulation results show that the proposed scheme can support more active users simultaneously than sub-channels, and it achieves a higher spectral efficiency compared to conventional MAC schemes.
THE CHANGING ROLE OF ACQUISITIONS

A series of forces—economic uncertainty, inflation, and low stock market valuations—have prompted major corporations to pursue mergers and acquisitions as the preferred route to corporate growth and profitability. The pendulum is likely to swing back in favor of internal development, however, as economic conditions change.
A Colorimetric Method for Trace Level Determination of Cobalt in Natural and Waste Water Samples

Abstract A colorimetric method which can be used to determine concentrations of cobalt as low as 0.1 mg/L in natural and waste water samples is developed. This method involves the complexation of cobalt with 1-nitroso-2-naphthol-3,6, disulfonic acid disodium salt at the pH of 6.0, and the measurement of the absorbance of the colored complex at 520 nm. The interference by other metals as well as common anions was also investigated. Under the conditions employed, cobalt determination was found to be free of any interference by various metal ions and anions. The effect of digestion process using the E.P.A procedure 3030E was also investigated. On synthetic samples, the results on the determination of cobalt in digested and undigested samples were same within experimental error showing the digestion procedures did not hinder the applicability of the method to environmental samples. The method was then applied to actual waste water samples to determine the concentration of cobalt. Greater than 98% recovery of ...
Note on the norms for the WRAT

The performance of the norms group on the Reading and Arithmetic subtests of the WRAT was compared with that of a representative national sampling. Systematic differences were found between the two data sets, and the effects of these differences on the current norms were illustrated. In general, the norms tend to underestimate a subject's level of achievement relative to the general population.
Powdered tart cherry supplementation effectively reduces markers of catabolism and perceptions of muscle soreness following an acute bout of intense endurance exercise

Background Consumption of tart cherry juice has been reported to effectively reduce inflammation, muscle damage, and muscle soreness following bouts of exercise. The purpose of this study was to determine if consumption of a powdered form of tart cherries derived from tart cherry skins prior to and following intense endurance exercise promotes similar positive results as seen with tart cherry juice consumption.
A review of liquid phase migration and methods for fabrication of functionally graded cemented tungsten carbide

Abstract Since functionally graded WC-Co (FG WC-Co) offers superior combinations of wear resistance, fracture toughness, and strength, and provides superior engineering performance over conventional homogeneous WC-Co, many processes have been developed to produce FG WC-Co, a few of which are commercialized today. However, with respect to the underlying principles on how the graded structures form in WC-Co, there are considerable gaps in understandings. Based on the most recent studies, the present authors examined the processes for making FG WC-Co and found that in most cases the formation of graded structure in WC-Co is achieved through liquid phase migration which can be induced by different techniques. Several representative FG WC-Co processes are reviewed and explained using the theory of liquid phase migration. A new process that induces liquid migration by carburizing fully sintered WC-Co is described.
Effects of an organic iodine compound priodax on tests of thyroid function.

VARIOUS organic iodine compounds used in radiology affect the succeeding tests of thyroid function. Certain iodine-containing compounds become associated with proteins in the serum (1) and are measured as protein-bound iodine. The serum protein-bound iodine (PBI), considered normally to consist predominantly of thyroxine, is therefore artefactually elevated. Some of the organic iodine compound does not associate with protein and the total iodine is raised, therefore, by an elevation in PBI, unbound organic iodine compound and iodide. The uptake by the thyroid of radioactive iodine may be reduced below normal. It has been assumed that this is due to a release from the organic iodine molecule of inorganic iodide—sometimes slowly over a long period of time. The development of myxedema following administration of organic iodine has been reported (2). The comparison of total iodine with PBI often indicates contamination with inorganic iodide or with organic iodine compounds un associated with protein. Butanol ...
Marked infidelity of human immunodeficiency virus type 1 reverse transcriptase at RNA and DNA template ends

Abstract Human immunodeficiency virus type 1 (HIV-1) is genetically highly variable. This is attributed to the error-prone nature of HIV-1 replication and its proclivity for recombination. During replication and recombination, reverse transcriptase (RT) must polymerize DNA to the 5' ends of multiple RNA and DNA template termini while converting HIV-1 RNA to double-stranded DNA. We have determined the fidelity of HIV-1 RT in vitro during polymerization to the 5' ends of HIV-1 long terminal repeat DNA template sequences and to the end of a partial HIV-1 genomic RNA template that mimics a recombination intermediate. HIV-1 RT readily extended recessed DNA primers to form full-length blunt-end DNA-DNA and DNA-RNA duplexes. In addition, HIV-1 RT catalyzed high yields of products with one to four extra nucleotides at the 3' ends of the nascent DNAs. These products were formed processively via a nontemplated mechanism that is highly specific for the addition of purine nucleotides (A > G >> T > or = C). Thus, HIV-1 RT is extremely unfaithful at both DNA and RNA template ends, introducing errors (extra nucleotides) in one out of every two or three nascent strands processively polymerized. This error rate is 1000 times higher than for HIV-1 RT-catalyzed errors at internal template positions. Blunt-end additions were also catalyzed by other retroviral RTs at relative rates of HIV-1 approximately Moloney murine leukemia virus > avian myeloblastosis virus. These data suggest a potentially important mechanism for retroviral mutation mediated by nontemplated blunt-end addition of purines prior to forced copy-choice recombination.
Plasma atrial natriuretic peptide levels during the rat estrous cycle, pregnancy, and puerperium.

The rat has been used as a model for studying the changes that occur in maternal blood volume and renal function during pregnancy. The role, if any, that atrial natriuretic peptide plays in regulating these changes is unknown, and little information is available on atrial natriuretic peptide levels at different stages of gestation in the rat. In this study we measured plasma atrial natriuretic peptide levels by radioimmunoassay in the rat at each stage of the estrous cycle, during the last 2 weeks of pregnancy, and in the early postpartum period. Atrial natriuretic peptide levels did not change during the estrous cycle. Atrial natriuretic peptide levels were low on days 10 to 15 of gestation but rose to become significantly higher than nonpregnant levels on days 16 to 18. On day 21 shortly before delivery, levels were similar to nonpregnant values. Postpartum, atrial natriuretic peptide levels rose immediately and remained elevated for the next 48 hours. These findings suggest that factors other than blood volume may mediate plasma atria] natriuretic peptide levels during pregnancy and the postpartum period.
Green, lean, and global supply chains

Purpose – The purpose of this paper is to examine the relationship among green, lean, and global supply chain strategies as found in the literature, with emphasis on the concurrent implementation of these three strategic initiatives, in order to develop a research agenda to guide theoretically based future research that informs managerial decision making.Design/methodology/approach – An extensive literature review is conducted to examine research and practice with respect to the concurrent implementation of green, lean, and global supply chain strategies.Findings – An in‐depth examination of the literature revealed drivers, barriers, converging, and contradictory points across the three supply chain strategies. Future research opportunities fall into four major themes: the need for theoretically grounded research, the need for a multi‐functional approach, the need for a systems approach that adds strategic insight, and the need for integrated measurement application. Managerial aspects are highlighted in ...
Absence of the falx cerebelli in a Chiari II malformation

After a review of the literature, we found no descriptions of the falx cerebelli in the Chiari II population. Other dural partitions in this group have been well-described. The aim of our study was to radiologically and at autopsy search for the falx cerebelli in this population. We retrospectively analyzed 50 CTs and 50 MRIs in children with a known Chiari II malformation, searching for either the falx cerebelli or internal occipital crest, the bony attachment for the falx cerebelli; these structures were also investigated in two patients at autopsy. We were unable to observe the falx cerebelli or internal occipital crest on any of the radiologic images or at autopsy. We theorize that a "crowded" posterior cranial fossa in these patients inhibits the development of the falx cerebelli and internal occipital crest.
Do chimpanzees tailor their gestural signals to fit the attentional states of others

The use of vocalizations and tactile gestures by seven juvenile chimpanzees was experimentally investigated. The subjects interacted with an experimenter who typically handed them food rewards. In some trials, however, the experimenter waited 20 s before doing so. In these trials the experimenter’s eyes were either open or closed, or the experimenter was either looking away from the subject or looking directly at him/her inquisitively with head movements. Although the chimpanzees produced at least one of the non-visual gestures mentioned (touching/tapping the experimenter or vocalizing) in 72% of all experimental trials, these actions and vocalizations were deployed without regard to the attentional state of their potential recipient, despite evidence that the subjects noticed the postures that defined the experimenter’s attentional state. The results are discussed in the context of the distinction between the evolution of an understanding of seeing/attention as an internal mental state versus an understanding of behavioral postures alone.
Field-aligned currents, convection electric fields, and ULF-ELF waves in the cusp

Nearly simultaneous observations from the Triad and Hawkeye satellites over the Southern Hemisphere, at low altitudes near the noon meridian and close to the usual polar cusp latitudes, show that in and near the polar cusp there exist several relationships between field-aligned currents (FACs), convection electric fields, ULF-ELF magnetic noise, broadband electrostatic noise and interplanetary magnetic fields. The most important findings are (1) the FACs directed into the ionosphere in the noon-to-dusk local time sector and directed away from the ionosphere in the noon-to-dawn local time sector and identified as region-1 permanent FACs (Iijima and Potemra, 1976a) and are located equatorward of the regions of antisunward (westward) convection; (2) the observations are consistent with a two-cell convection pattern symmetric in one case (throat positioned at noon) and asymmetric in another (throat located in a sector on the forenoon side in juxtaposition to the region of strong convection on the afternoon side); and (3) fine-structure FACs are responsible for the generation of ULF-ELF noise in the polar cusp.
Library technology initiatives and community building

Library technology initiatives naturally stand at the intersection of people and machines, and represent perhaps the most important case we have for understanding the ways in which our digital libraries can impact and be impacted by the social groups that interact with them. In many cases libraries have established facilities‐based centers to introduce new technologies to users. These centers offer places and processes within which and by which users can familiarize themselves with how they themselves can use these new information technologies in their own work. In other cases libraries have established wholly virtual “spaces” where older “physical” collections can be used in wholly new ways. In every case, whether physical, virtual or both, users groups are variously extended, changed,and sometimes alienated.
PρT Experimental Measurements and Data Correlation of Pentaerythritol Esters

The new refrigerant fluids are generally not compatible with traditional mineral oils used for the lubrification of compressors. Different typologies of oils have been proposed, such as polyalkylene glycol (PAG), alkylbenzene (AB), and polyol ester (POE) oils. New thermodynamic models are necessary to describe well the behavior of these fluids, but at the moment only few experimental data are available in the literature. The work presented in this paper is part of our research program aimed to evaluate the solubility of refrigerants in commercial oils. The density of five different pentaerythritol esters is presented, which are used as components of the commercial POE oils (i.e., pentaerythritol ester of butyric acid (PEC4), pentaerythritol ester of valeric acid (PEC5), pentaerythritol ester of hexanoic acid (PEC6), pentaerythritol ester of heptanoic acid (PEC7), and pentaerythritol ester of octanoic acid (PEC8)). The experimental compressed liquid density data were correlated by means of a particular equ...
Hall Sensors Using Piezoresistive Transducer Fabrication Process

A piezoresistive transducer (PRT) pressure sensor would be able to sense a magnetic field and provide an adequate Hall effect output. In this study, two different types of boron-doped transducers, X-ducer and picture-frame transducer (also called micro Wheatstone-bridge transducer) were tested for the Hall effect. It is found that the currently used fabrication process and packaging for PRT pressure sensors do not need to be altered for Hall sensors. However, a slight mask modification is necessary to use an X-ducer instead of a picture-frame transducer for the Hall effect sensing because the X-ducer is at least 50 times more sensitive than the picture-frame transducer. The sensitivity calculated using the Hall theory and estimated hole mobility velocity is in reasonably good agreement with experimental results.Copyright © 2006 by ASME
Ischemic optic neuropathy in male veterans prescribed phosphodiesterase-5 inhibitors.

Purpose To determine the feasibility of a case-control study of phosphodiesterase (PDE)-5 inhibitors and nonarteritic ischemic optic neuropathy (NION). Design Retrospective cohort study using the National Veterans Health Administration's pharmacy and clinical databases. Methods setting: National database. patient population: Male veterans 50 years of age and older with newly diagnosed NION or "possible" NION. interventional procedure: Dispensed prescription for a PDE-5 inhibitor. outcome measure: Incidence of NION and "possible" NION based on exposure to PDE-5 inhibitors. Results The relative risk of NION among men prescribed a PDE-5 inhibitor was 1.02 (95% confidence interval [CI]: 0.92 to 1.12). The relative risk of possible NION among men prescribed a PDE-5 inhibitor was 1.34 (95% CI: 1.17 to 1.55). Conclusions The collective risk of NION and possible NION was marginally significant (relative risk [RR] 1.10 95% CI: 1.02 to 1.20). A case-control study, in which the dependent variable is NION and the effect size of the PDE-5 inhibitor is assumed small, is feasible.
A direct test of nitrogen and phosphorus limitation to net primary productivity in a lowland tropical wet forest

Experimental evidence for limitation of net primary productivity (NPP) by nitrogen (N) or phosphorus (P) in lowland tropical forests is rare, and the results from the few existing studies have been inconclusive. To directly test if N or P limit NPP in a lowland tropical wet forest in Costa Rica, we conducted a full factorial fertilization experiment (4 treatments × 6 replicates in 30 × 30 m plots). We focused on the influence of tree size and taxa on nutrient limitation, because in these forests a wide variety of tree functional traits related to nutrient acquisition and use are likely to regulate biogeochemical processes. After 2.7 years, a higher percentage of trees per plot increased basal area (BA) with P additions (66.45% ± 3.28% without P vs. 76.88% ± 3.28% with P), but there were no other community-level responses to N or P additions on BA increase, litterfall productivity, or root growth. Phosphorus additions resulted in doubled stem growth rates in small trees (5–10 cm diameter at breast height (dbh); [P ≤ 0.01]) but had no effect on intermediate (10–30 cm dbh) or large trees (>30 cm dbh). Phosphorus additions also increased the percentage of seedling survival from 59% to 78% (P < 0.01), as well as the percentage of seedlings that grew (P = 0.03), and increased leaf number (P = 0.02). Trees from Pentaclethra macroloba, the most abundant species, did not increase growth rates with fertilization (P = 0.40). In contrast, the most abundant palms (Socratea exorrhiza) had more than two times higher stem growth rates with P additions (P = 0.01). Our experiment reiterates that P availability is a significant driver of plant processes in these systems, but highlights the importance of considering different aspects of the plant community when making predictions concerning nutrient limitation. We postulate that in diverse, lowland tropical forests “heterogeneous nutrient limitation” occurs, not only driven by variability in nutrient responses among taxa, but also among size classes and potential functional groups. Heterogeneous responses to nutrient additions could lead to changes in forest structure or even diversity in the long term, affecting rates of NPP and thus carbon cycling.
The dynamics of contraceptive use: an overview.

By 1990 the contraceptive prevalence rate in developing countries is expected to exceed 50% of couples of reproductive age and to be only 10% below the rate recorded in developed countries 25 years ago. At this time traditional methods account for only 10% of contraceptive use in developing countries. This trend toward increasing contraceptive usage calls for a shift in research from static measures of the determinants of contraceptive use toward the dynamics of habitual use. Little is known about the sustainability of contraceptive use at the level of the individual couple--a weakness that limits analysis of the dynamic features of the reproductive process and the decision making processes involved. The traditional reliance on national probability sample surveys for knowledge of family planning behaviors must be supplemented by longitudinal data collection schemes including panel studies. Cross-sectional surveys are not able to provide the information needed on temporal variations in factors such as the absence of a spouse lactation and advancing age on the risk of conception and the motivation to accept contraception. Contraceptive prevalence measures are in need of refinement to take account of how correctly and for how long nonclinical methods are used and their effectiveness. In addition it is important for program personnel to know whether the predictors of current contraceptive use status (maternal education socioeconomic status service proximity etc) also influence continuation or the selection of another method after discontinuation. Still other inadequacies of periodic sample surveys include problems in detecting pregnancy wastage the underestimation of coitus-dependent methods and a failure to consider the impact of contraceptive service delivery program administration.
Francisella tularensis Strain Typing Using Multiple-Locus, Variable-Number Tandem Repeat Analysis

Francisella tularensis, the etiological agent of tularemia, is found throughout the Northern hemisphere. After analyzing the F. tularensis genomic sequence for potential variable-number tandem repeats (VNTRs), we developed a multilocus VNTR analysis (MLVA) typing system for this pathogen. Variation was detected at six VNTR loci in a set of 56 isolates from California, Oklahoma, Arizona, and Oregon and the F. tularensis live vaccine strain. PCR assays revealed diversity at these loci with total allele numbers ranging from 2 to 20, and Nei's diversity index values ranging from 0.36 to 0.93. Cluster analysis identified two genetically distinct groups consistent with the current biovar classification system of F. tularensis. These findings suggest that these VNTR markers are useful for identifying F. tularensis isolates at this taxonomic level. In this study, biovar B isolates were less diverse than those in biovar A, possibly reflecting the history of tularemia in North America. Seven isolates from a recent epizootic in Maricopa County, Ariz., were identical at all VNTR marker loci. Their identity, even at a hypervariable VNTR locus, indicates a common source of infection. This demonstrates the applicability of MLVA for rapid characterization and identification of outbreak isolates. Future construction of reference databases will allow faster outbreak tracking as well as providing a foundation for deciphering global genetic relationships.
Nuclear thyroid hormone binding activities and serum iodothyronine levels in aging rats

Since aging mammals present a spectrum of physiologic conditions that mimic the hypothyroid state, we measured serum thyroid hormone levels and the maximum binding capacities and affinities of solubilized nuclear thyroid hormone binding proteins from liver, kidney, heart and cerebellum in healthy male and female Wistar rats of various postpubertal ages (3–4, 7–8, 15–17 mo; 12 rats/group). In cross-sectional measurements, serum levels of T3 increased by about 40% (3 mo to 15 mo) in both males and females; T4 levels increased in males by 22% but decreased slightly in females. The affinity of T3 and T4 binding to nuclear receptors was highly conserved between tissues, male vs female and with age (mean ± SE: T3 Kd = 0.90±0.4 × 10−10M; T4 Kd = 6.02±0.28 × 10−10M). However, maximum binding capacity in the heart decreased significantly by 15 mo for T3 (−60% in male, −46% in female) and T4 (−58% in males and −45% in females). Cerebellum showed a pattern similar to the heart in loss of binding capacity with males showing a 56% decrease and females showing a 53% decrease in nuclear T3 binding activity. A trend toward decreased cerebellar T4 binding in the 3–15 mo period missed significance for males and females. By contrast, hormone binding in liver and kidney generally increased through 15 mo of age for both T3 and T4. We conclude that certain tissues containing mitostatic cells (heart and cerebellum) may selectively lose nuclear thyroid hormone receptors during post-pubertal aging.
Finite-dimensional irreducible Uq(sl2)-modules from the equitable point of view

Abstract We consider the quantum algebra U q ( sl 2 ) with q not a root of unity. We describe the finite-dimensional irreducible U q ( sl 2 ) -modules from the point of view of the equitable presentation.
Electrochemical membrane separation of chlorine from gaseous hydrogen chloride waste

Abstract Hydrogen chloride is a gas-phase by-product of many manufacturing chlorination processes. Growing environmental concerns have prompted several techniques for converting hydrogen chloride to elemental chlorine for recycling. A novel electrochemical membrane process has been developed for the recovery of chlorine from gaseous hydrogen chloride waste. Hydrogen chloride is reduced at the cell cathode, producing hydrogen gas and chloride ions. The chloride ions migrate across the molten salt electrolyte-saturated membrane to the anode where chlorine is evolved by oxidation. Experiments began with free electrolyte trials in the absence of a membrane separator and were followed by a single membrane cell study. Preliminary studies show that electrochemical membrane separation is a feasible alternative for the removal of chlorine from hydrogen chloride. The results indicate that chlorine can be effectively removed from a hydrogen chloride gas mixture at reasonable voltages, resulting in a high conversion efficiency. The proposed system offers advantages over conventional means such as on-site chlorine recycling in a single-step and on a continuous basis.
Effect of Earth's Rotation in Neutron Interferometry

In a neutron interferometer experiment which can successfully demonstrate a quantitative fringe shift due to the different gravitational potential for the neutron in the two legs of the apparatus, an adjunctive consideration must be the nonzero angular velocity of Earth and the lab. As in the classic Michelson-Gale-Pearson experiment done with light, and offset in the fringe pattern is predicted. Such a shift may not be subliminal at present precision levels.
Differences in visually evoked responses in albino versus hoded rats

Abstract Single and summed visually evoked cortical responses of albino and hooded rats were compared before and after monocular occlusion or enucleation to determine if differences in optic tract terminations between strains of rats could be detected by variation in the electrical input recorded at the cortex. Peak latencies were earlier in the hooded than the albino rat under all conditions. The minimum flash intensity at which primary components appeared in the summed evoked response was lower for the albino than for the hooded rat. The response contralateral to the intact eye following enucleation was of much larger amplitude, although no differences were apparent in the background EEG. The ipsilateral response was more like the contralateral response in the hooded than in the albino rat. The latter finding is consistent with anatomical and behavioral reports.
Perfusion deficit versus anatomic visualization in detection of pulmonary emboli via electron-beam CT: validation in swine

We present here our initial findings regarding the utility of functional x-ray CT imaging in determining the presence of pulmonary emboli. Recently, x-ray CT has been reported to be a promising technique in detecting pulmonary emboli through direct visualization of the clot as a filling defect of the reconstructed vascular lumen with CT scanning occurring during i.v. contrast drip. To determine whether functional imaging via the dynamic mode of electron beam CT might add to the sensitivity and specificity of pulmonary emboli diagnosis through the visualization of pulmonary parenchymal blood flow and its associated temporal parameters, we scanned 32 pigs and report here our findings on 17 pigs evaluated to date. Findings to date show that the evaluation of flow deficits detected via electron beam CT with a small 2-3 sec. bolus contrast injection has the potential to provide improvement in embolus detection over visual inspection of this section CT/continuous infusion contrast where the viewer is looking for unenhanced regions in the pulmonary arteries.
A minimum-reaction-flux solution to master-equation models of protein folding.

Master equations are widely used for modeling protein folding. Here an approximate solution to such master equations is presented. The approach used may be viewed as a discrete variational transition-state theory. The folding rate constant kf is approximated by the outgoing reaction flux J, when the unfolded set of macrostates assumes an equilibrium distribution. Correspondingly the unfolding rate constant ku is calculated as Jpu∕(1−pu), where pu is the equilibrium fraction of the unfolded state. The dividing surface between the unfolded and folded states is chosen to minimize the reaction flux J. This minimum-reaction-flux surface plays the role of the transition-state ensemble and identifies rate-limiting steps. Test against exact results of master-equation models of Zwanzig [Proc. Natl. Acad. Sci. USA 92, 9801 (1995)] and Munoz et al. [Proc. Natl. Acad. Sci. USA 95, 5872 (1998)] shows that the minimum-reaction-flux solution works well. Macrostates separated by the minimum-reaction-flux surface show a gap in pfold values. The approach presented here significantly simplifies the solution of master-equation models and, at the same time, directly yields insight into folding mechanisms.
Is rat soleus muscle recruited during swimming

Radiolabeled microspheres were used to measure blood flows (BF) among and within the ankle plantar flexor muscles of rats during swimming and during treadmill running. During swimming, BF was significantly elevated over preexercise quadrupedal standing in plantaris and red and middle portions of gastrocnemius muscles, but was significantly lower in soleus muscles. During treadmill locomotion at 60 m · min−1, BF in soleus muscle was the same as during preexercise, while BF to plantaris and red and middle gastrocnemius muscles was significantly increased. These data suggested soleus muscle was not active during swimming, which contrasts with terrestrial activities. Measurement of glycogen use in the muscles supported this interpretation. Since hindpaw stroke frequency during swimming is similar to stride frequency during treadmill running at 60 m · min−1, contraction cycling times do not provide an adequate explanation for the apparent failure to recruit soleus muscle during swimming. We suggest the swimming rat may provide an interesting model for the study of differential slow and fast muscle recruitment patterns.
Response of cardiac myocytes to a ramp increase of diacylglycerol generated by photolysis of a novel caged diacylglycerol.

To test the responsiveness of living cells to the intracellular messenger diacylglycerol, we developed a prototype caged diacylglycerol compound, 3-O-(alpha-carboxyl-2,4-dinitrobenzyl)-1 ,2-dioctanoyl-rac-glycerol (designated alpha-carboxyl caged diC(8)), that produces dioctanoylglycerol (diC(8)) on photolysis. Alpha-Carboxyl caged diC(8) is biologically inert toward diacylglycerol kinase and protein kinase C in vitro and is readily incorporated into cardiac myocyte membranes, where it has no effect before irradiation. Exposure to near-UV light releases biologically active diC8 in good yield (quantum efficiency = 0.2). Here we examine a cellular response to controlled elevation of diC8 within single cardiac myocytes. Twitch amplitude was monitored in electrically stimulated myocytes, and a ramp increase in the concentration of diC(8) was generated by continuous irradiation of cells loaded with the caged compound. The myocyte response was biphasic with a positive inotropic phase (39% increase in twitch amplitude), followed by a large negative inotropic phase (>80% decrease). The time to peak inotropy for both phases depended on the light intensity, decreasing from 376 +/- 51 S to 44 +/- 5 s (positive phase) and 422 +/- 118 S to 51 +/- 9 S (negative phase) as the light intensity was increased eightfold. Both phases were inhibited by the protein kinase C inhibitor chelethyrine chloride. An increase in extracellular K+ from 5 mM to 20 mM to partially depolarize the cell membrane eliminated the positive inotropic phase, but the negative inotropic response was largely unaltered. The results reveal new features in the response of cardiac muscle to diacylglycerol, including a positive inotropic phase and a complex responsiveness to a simple linear increase in diacylglycerol. The effects of photoreleased diC(8) were similar to the effects of opiate agonists selective for kappa receptors, consistent with a major role for diacylglycerol in these responses.
Warranty Cost Prediction Using the Mahalanobis-Taguchi System

In any competitive market, businesses need to differentiate their offerings. Many industries use a warranty as an offering that not only differentiates the product or service, but also extends the customer’s expected durability of the product or service. By offering to share the risk of a customer’s purchase in the form of a warranty, a business assumes the cost of poor quality and therefore should have a vested interest to reduce this cost thus maximizing its profits. Warranty cost prediction methods are used by many leading companies, but these methods typically only focus on failure reduction as cost avoidance. Additional dimensions should be considered when predicting warranty cost. This paper presents the application of the Mahalanobis-Taguchi System to forecast warranty cost based on multivariate data. Using Mahalanobis-Taguchi System, a product or service’s warranty cost can be predicted using multiple characteristics thus providing a more complete estimate. The Mahalanobis-Taguchi System also enables businesses to estimate their warranty cost as early as conceptual design, due to the method’s ability to forecast based on small, correlated data sets. A case study utilizing warranty data is also provided to illustrate the technique.Copyright © 2009 by ASME
Solving problems on recursively constructed graphs

Fast algorithms can be created for many graph problems when instances are confined to classes of graphs that are recursively constructed. This article first describes some basic conceptual notions regarding the design of such fast algorithms, and then the coverage proceeds through several recursive graph classes. Specific classes include trees, series-parallel graphs, k-terminal graphs, treewidth-k graphs, k-trees, partial k-trees, k-jackknife graphs, pathwidth-k graphs, bandwidth-k graphs, cutwidth-k graphs, branchwidth-k graphs, Halin graphs, cographs, cliquewidth-k graphs, k-NLC graphs, k-HB graphs, and rankwidth-k graphs. The definition of each class is provided. Typical algorithms are applied to solve problems on instances of most classes. Relationships between the classes are also discussed.
Measurements of short-term thermal responses of coniferous forest canopies using thermal scanner data

Thermal Infrared Multispectral Scanner (TIMS) data were collected over a coniferous forest in western Oregon. Concurrent radiosonde measurements of atmospheric profiles of air temperature and moisture provided inputs to LOWTRAN6 for atmospheric radiance corrections of the TIMS data. Surface temperature differences measured by the TIMS over time between flight lines were combined with surface radiative energy balance estimates to develop thermal response numbers (TRN). These numbers characterized the thermal response of the diffent surface types. Barren surfaces had the lowest TRN, whereas the forested surfaces had the highest.
Pavlovian determiners of behavioral momentum

Pigeons pecked keys on a six-component multiple schedule of food reinforcement arranged in successive pairs on three keys. On all three keys, the schedule in the first component was variable-interval 120 sec. On one key, the second component was variable-time 24 sec; on another, it was variable-time 120 sec; and on the third, extinction. Pairs of components were separated by timeout. In this arrangement, second-component stimuli were differentially correlated with food in their presence, and first-component stimuli were differentially correlated with second-component food in serial fashion. After baseline performance stabilized, resistance to change was assessed by prefeeding, by discontinuing food, and by presenting free food at random times throughout sessions. There was no consistent relation between baseline response rates in the first component and reinforcement rate in the second component. When assessed by prefeeding or extinction, resistance to change in the first component was positively related to reinforcement rate in the second component, demonstrating that serial stimulus-reinforcer contingencies affected resistance to change.
Classifying wheelchair propulsion patterns with a wrist mounted accelerometer

In this paper, we describe a manual wheelchair propulsion classification system which recognizes different patterns using a wrist mounted accelerometer. Four distinct propulsion patterns have been identified in a limited user study. This study is the first attempt at classifying wheelchair propulsion patterns using low-fidelity, body-worn sensors. Data was collected using all four propulsion patterns on a variety of surface types. The results of two machine learning algorithms are compared. Accuracies of over 90% were achievable even with a simple classifier such as k-Nearest Neighbor (kNN). Being able to identify current propulsion patterns and provide real-time feedback to novice and expert wheelchair users is potentially useful in preventing future repetitive use injuries.
A Pragmatic Framework for Ethical Decision Making: The Limits of Professional Codes

The need for professionals to make informed ethical choices in design and management of information systems is more important than ever. However, the relative newness of the information profession and the dynamism of information technology mean that traditional foundational approaches to ethics, while useful, are inadequate for today's designers and managers. This paper proposes a pragmatic ethical framework that suggests a possible relationship between the maturity and dynamism of a professional field to different approaches to ethical decision making. It concludes that relatively new fields such as software engineering can benefit from process-based approaches, and that such fields are well positioned to inform other dynamic professions that face similar challenges in making ethical decisions.
A FEM/VOF hybrid formulation for underfill encapsulation modeling

Abstract In this paper we present large-scale numerical models for underfill encapsulation processes. The numerical formulation consists of the finite element method coupled with the volume of fluid technique and is based on generalized Hele–Shaw equations. The material behavior is modeled using rheologic kinetic models to predict material bulk properties (i.e. viscosity) and reactions models during the curing process (i.e. gel time). Some simulation examples are presented that demonstrate the applicability of the models to the underfill encapsulation process.
Longitudinal modeling of genetic and environmental influences on self-reported availability of psychoactive substances: alcohol, cigarettes, marijuana, cocaine and stimulants.

Background. Although an obvious environmental factor influencing drug use, the sources of individual differences in drug availability (DA) are unknown. Method. This report is based on 1788 adult males from the Mid-Atlantic Twin Registry who participated in a structured telephone interview that included retrospective assessments of DA (cigarette, alcohol, marijuana, cocaine and stimulants) between ages 8 and 25. We fitted a biometric dual change score (DCS) model, adapted for ordinal data, to model latent growth and estimate the genetic and environmental components of variance over time. Results. DA, despite being considered an environmental risk factor, is under both genetic and environmental control. For cigarette, alcohol, marijuana and cocaine availability, there was an overall increase in additive genetic variance and a decline in shared environmental variance over time. Non-shared environmental variance remained steady. Stimulant availability did not follow this pattern. Instead, there was an upswing in shared environmental effects with increasing age. Conclusion. We have modeled the genetic and environmental architecture of changes in DA across adolescence. The rise in additive genetic variance over time coincides with acceleration in the expression of individual differences, probably brought on by an increase in personal freedom and a reduction in social constraints. Understanding the etiology of DA is likely to reveal key components, acting directly or indirectly, in the pathway(s) leading to drug initiation, abuse and dependence.
High affinity binding of [3H]R5020 and [3H]progesterone by putative progesterone receptors in cytosol and nuclear extract of turtle oviduct

The purpose of this investigation was to identify and characterize putative cytosolic and nuclear forms of progesterone receptor in the female reproductive tract of a turtle, Chrysemys picta. A dextran-coated charcoal adsorption assay and DNA-cellulose affinity chromatography were used as the primary methodologies with [3H]R5020 [3H-labeled 17 alpha-dimethyl-19-norpregna-4,9-diene-3,20-dione) and [3H]progesterone (P4) as the ligands. The receptor was of high affinity (Kd = 4.7 X 10(-10) M for [3H]P4; 2.2 X 10(-10) M for [3H]R5020) and limited capacity (500-6000 fmol/g tissue wet wt). Association was rapid (apparent equilibrium being reached in 30-40 min), as was dissociation (t1/2 = 45 min for [3H]P4 and 180 min for [3H] R5020). The putative receptor demonstrated strict steroid specificity, binding progestins but not estrogens, androgens, or glucocorticoids. Heterogeneity of the cytosolic receptor was demonstrated as two forms eluting off DNA-cellulose columns at 0.2- and 0.3-M salt concentrations. Binding of cytosolic receptor to DNA-cellulose was not increased by preexposure of cytosol to 25 C for 30 min. Some variations in cytosolic, but not nuclear, receptor were associated with different stages of the reproductive cycle and were positively correlated with body weight. Preliminary studies using an explant culture system suggest that the progesterone receptor in turtle oviduct may be maintained by estrogen and translocated from the cytosol to the nucleus by P4. In summary, we have partially characterized a putative P4 receptor in the oviduct of the turtle that is similar to mammalian and avian P4 receptors in specificity, affinity, and other physicochemical properties, supporting the idea that steroid receptor proteins have been highly conserved in vertebrate evolution. However, temperature sensitivity of activation and DNA affinity are different in the turtle and suggest modifications that may be related to physiological adaptation in such a poikilothermic species.
A Link between ethylene and auxin uncovered by the characterization of two root-specific ethylene-insensitive mutants in Arabidopsis.

The plant hormone ethylene participates in the regulation of a variety of developmental processes and serves as a key mediator of plant responses to biotic and abiotic stress factors. The diversity of ethylene functions is achieved, at least in part, by combinatorial interactions with other hormonal signals. Here, we show that ethylene-triggered inhibition of root growth, one of the classical effects of ethylene in Arabidopsis thaliana seedlings, is mediated by the action of the WEAK ETHYLENE INSENSITIVE2/ANTHRANILATE SYNTHASE α1 (WEI2/ASA1) and WEI7/ANTHRANILATE SYNTHASE β1 (ASB1) genes that encode α- and β-subunits of a rate-limiting enzyme of Trp biosynthesis, anthranilate synthase. Upregulation of WEI2/ASA1 and WEI7/ASB1 by ethylene results in the accumulation of auxin in the tip of primary root, whereas loss-of-function mutations in these genes prevent the ethylene-mediated auxin increase. Furthermore, wei2 and wei7 suppress the high-auxin phenotypes of superroot1 (sur1) and sur2, two auxin-overproducing mutants, suggesting that the roles of WEI2 and WEI7 in the regulation of auxin biosynthesis are not restricted to the ethylene response. Together, these findings reveal that ASA1 and ASB1 are key elements in the regulation of auxin production and an unexpected node of interaction between ethylene responses and auxin biosynthesis in Arabidopsis. This study provides a mechanistic explanation for the root-specific ethylene insensitivity of wei2 and wei7, illustrating how interactions between hormones can be used to achieve response specificity.