cssi/SciSciGPT-SciSciNet huggingface dataset:
Preclinical Cancer Therapy in a Mouse Model of Neurofibromatosis-1 Optic Glioma

Mouse models of human cancers afford unique opportunities to evaluate novel therapies in preclinical trials. For this purpose, we analyzed three genetically engineered mouse (GEM) models of low-grade glioma resulting from either inactivation of the neurofibromatosis-1 (Nf1) tumor suppressor gene or constitutive activation of KRas in glial cells. Based on tumor proliferation, location, and penetrance, we selected one of these Nf1 GEM models for preclinical drug evaluation. After detection of an optic glioma by manganese-enhanced magnetic resonance imaging, we randomized mice to either treatment or control groups. We first validated the Nf1 optic glioma model using conventional single-agent chemotherapy (temozolomide) currently used for children with low-grade glioma and showed that treatment resulted in decreased proliferation and increased apoptosis of tumor cells in vivo as well as reduced tumor volume. Because neurofibromin negatively regulates mammalian target of rapamycin (mTOR) signaling, we showed that pharmacologic mTOR inhibition in vivo led to decreased tumor cell proliferation in a dose-dependent fashion associated with a decrease in tumor volume. Interestingly, no additive effect of combined rapamycin and temozolomide treatment was observed. Lastly, to determine the effect of these therapies on the normal brain, we showed that treatments that affect tumor cell proliferation or apoptosis did not have a significant effect on the proliferation of progenitor cells within brain germinal zones. Collectively, these findings suggest that this Nf1 optic glioma model may be a potential preclinical benchmark for identifying novel therapies that have a high likelihood of success in human clinical trials.
On the use of compatibility conditions for the strain in linear and non-linear theories of mechanics

This short note addresses a misconception that seems to be prevalent with regard to the use of compatibility conditions for the strains in both the linearized and non-linear theories of elasticity, when one uses a “stress-based” approach.
Single-atom test of all-atom empirical potentials: Fe in myoglobin.

The measured Fe vibrational density of states in deoxy-myoglobin, obtained from nuclear resonance vibrational spectroscopy, is compared to results from a normal-mode analysis using an all-atom empirical potential. Substantial disagreement reveals that for this one atom, the empirical potential does not accurately describe the actual forces. A Green function technique is developed to calculate the iron vibrational spectrum of deoxy-myoglobin by coupling the independently calculated heme and globin normal modes; nonbonded interactions between the heme molecule and the protein are essential for a good fit to the measurements. A projection of the eigenvectors from this potential onto the displacements induced by binding of CO demonstrates that normal modes over a broad range centered around 50−150 cm-1 may drive the ligand-induced structural changes.
Kinetics of the crosslinking reaction of a bisnadimide model compound in thermal and microwave cure processes

The kinetic studies of the crosslinking reaction of a nadic end-capped imide model compound, N,N′-(oxydi-3,4′-phenylene) bis(5-norbornene-2,3-dicarboximide), a bisnadimide, in thermal and microwave processes were investigated. The conversion of the endo isomer to exo isomer proceeds at a much lower temperature than the crosslinking reaction. The crosslinking reaction was monitored by the combined decrease in the infrared absorptions of the endo and exo isomers at 840 and 780 cm−1, respectively. The decrease in the concentration of starting materials follows first-order kinetics in the thermal and microwave processes. At the same temperatures (230 or 280°C), the crosslinking reaction proceeds at about 10 times faster in the microwave process than in the thermal process. Solid-state 13C-NMR showed no significant loss in C=C double bond resonance in the cured products by comparison with the starting material. This study provides direct evidence that the microwave process may be an efficient method to cure nadic end-capped polyimides. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2653–2665, 1998
Modeling and analysis of the San Francisco City Clinic Cohort (SFCCC) HIV-epidemic including treatment

We investigate two HIV/AIDS epidemic models. The first model represents the early San Francisco men having sex with men (MSM) epidemic. We use data from the San Francisco City Clinic Cohort Study (SFCCC), documenting the onset of HIV in San Francisco (1978-1984). The second model is a 'what-if' scenario model including testing and treatment in the SFCCC epidemic. We use compartmental, population-level models, described by systems of ordinary differential equations. We find the basic reproductive number R0 for each system, and we prove that if R0 1, the DFE is unstable. In addition, when R0>1, both systems have a unique endemic equilibrium (EE). We show that treatment alone would not have stopped the San Francisco MSM epidemic, but would have significantly reduced its impact.
Interleukin 1 beta down-regulates collagen and augments collagenase expression in human intestinal smooth muscle cells

Abstract BACKGROUND & AIMS: Smooth muscle cells resident in the intestinal wall play a significant role in the healing of the injured intestine and in the fibrosis that complicates Crohn's disease. The cytokine interleukin 1 beta (IL-1 beta) is involved in inflammatory bowel disease. The aim of this study was to determine the action of IL-1 beta on proliferation and collagen metabolism in human intestinal smooth muscle cells. RESULTS: IL-beta caused a three-fold increase in [3H]thymidine uptake at 100 pmol/L. This mitogenic effect was equipotent with that of platelet-derived growth factor when cells were exposed to IL-beta for 48 vs. 24 hours. IL-beta inhibited the secretion of procollagen into culture medium by 70% and the accumulation of newly synthesized procollagen in cells by 55%. In addition, IL-beta caused a concentration-dependent inhibition of steady-state levels of procollagen I and III messenger RNA (85% inhibition at 100 pmol/L) and a 3-5-fold augmentation of collagenase messenger RNA levels. CONCLUSIONS: IL-beta is mitogenic for human intestinal smooth muscle cells, but this action is associated with a concomitant down-regulation of collagen synthesis and secretion and an augmention of collagenase expression. (Gastroenterology 1996 Feb;110(2):344-50)
Mixed arbuscular mycorrhizae from the Triassic of Antarctica

Arbuscular mycorrhizae are the most ubiquitous of mycorrhizal fungi, that have formed mutualistic relationships with virtually almost all major groups of vascular plants. Five genera of arbuscular ...
Absorption and emission of radiation in the region of an avoided level crossing

The spectrum for absorption and emission of radiation by colliding atoms or a diatomic molecule is calculated for spectral regions dominated by an avoided level crossing. Example processes are absorption during an atom-atom collision with separation to either crossing atomic state, total absorption to both crossing states, and spontaneous emission during a collision with either state initially populated. Absorption and emission by bound diatomic molecules (including photodissociation) is described by the theory, and as an example it is applied to the ${\mathrm{Cs}}_{2}$ A-X band. Spectra due to single-velocity and impact-parameter collisions, as well as thermal and impact-parameter averages, are given. The shapes of the resulting spectra are parametrized by the interaction strength (or excitation transfer probability) between the crossing levels and the slopes of the ground- and excited-state potentials (assumed constant) in the region of the level crossing. The theory is applied to two observations of such regions that have been reported. We conclude that measurements of spectra in the region of level crossing is a very powerful diagnostic of the potentials and transfer probability in the level-crossing region, which is responsible for most inelastic atom-atom energy-transfer processes.
A meta-analytical estimation of the detection limits of methods for Salmonella in food

Abstract The validation of microbial detection methods for foods does not typically state a limit of detection value. Therefore performances of rapid and reference methods for Salmonella detection in foods were compared retrospectively using data from 49 published studies. A total of 576 values for the limit of detection (LOD50) were calculated. The major scientific variables in these independent validation studies were food matrices, Salmonella serovars, and method types (reference, cultural and immunological and nucleic acid based). The basic design feature of the original studies was comparison of the performances of new methods with those of cultural reference methods. A major experimental design variable was the number of laboratories per study. There were 29 single laboratory studies with 20 replicates per level of Salmonella spiked into the food matrix. The 20 multi-laboratory (N ≥ 10) studies had 5–6 replicates per level of Salmonella. The LOD50 values of the dataset had a mean value of 0.021 MPN g− 1 (standard deviation range (0.013–0.036) and the distribution of their logarithms was symmetrical about the logarithm of the mean if the outlier values were discounted. Eighty-nine percent of the values ranged from 0.01 to 0.04 MPN g− 1. On this basis about 11% of the values were deemed outliers. About three-quarters of them were > 0.04 MPN g− 1. The distribution derived in this study can be used as a bench mark against which to evaluate LOD50 data generated in future studies of detection methods for Salmonella in foods and potentially offers a possible way to streamline method validation study experimental design.
Plant community composition as a function of geochemistry and hydrology in three Appalachian wetlands

Appalachian mountain wetlands are uncommon and diverse ecosystems; however, they are often susceptible to extensive alteration or destruction due to coal mining, highway construction, and quarrying. This study aimed to determine vegetation composition at three pristine wetlands and establish relationships with previously reported hydrologic, edaphic, and porewater characteristics to provide baseline data that could enhance wetland mitigation or restoration projects. Herbaceous vegetation was assessed by visually estimating percent cover for bryophyte and vascular species and by determining stem density for vascular taxa using 1 m2 quadrats located along transects. Multiple response permutation procedures (MRPPs) based upon importance values confirmed that species composition differed significantly (P < 0·001) among the sites. Nonmetric multi-dimensional scaling (NMDS) indicated that soil moisture conditions during the fall, soil chemistry, and porewater chemical composition influenced plant community composition. The first wetland (Martins Fork) was primarily dominated by Osmunda cinnamomea, Osmunda regalis, and Sphagnum palustre in response to drier soil during the fall season, higher soil pH, and weakly minerotrophic soil and porewater. The second wetland (Kentenia) was overwhelmingly dominated by S. palustre due to lower soil pH and persistently high water levels. Vegetation at the third wetland (Four Level) was distinguished by strongly dominant Scirpus polyphyllus and Glyceria striata and responded to higher soil and porewater Ca, Mg, and P concentrations as well as a light intensity gradient. The diverse vegetation and physico-chemical characteristics indicate that these sites, although small in size, support regional biodiversity and are potential reference wetlands. Copyright © 2011 John Wiley & Sons, Ltd.
Microphase separated structures in the solid and molten states of double-crystal graft copolymers of polyethylene and poly(ethylene oxide)

Abstract Transitions from one microphase separated structure in the solid state to a different one in the molten state in polyethylene-graft-poly(ethylene oxide) copolymers, PE-g-PEO, were investigated by variable temperature X-ray scattering measurements and thermal analyses. Small-angle X-ray scattering patterns from polymers with PEO grafts with 25, 50 and 100 ethylene oxide (EO) units show that the polymer passes through three distinct structures at ∼10 nm length scales with increase in temperature (T): lamellar structures of PE and PEO at T TmPE when both PE and PEO are molten (Tm refers to the melting temperature). These phase transformations also occur during cooling but with hysteresis. Crystalline phases of PEO side chains and PE main chains could be identified in the wide-angle X-ray diffraction profiles indicating that the PE backbone and PEO grafts crystallize into separate domains, especially with longer grafted chains (50 and 100 units). At EO segment lengths > 50, PEO shows the expected increase in melting and crystallization temperatures with the increase in the grafted chain length. PE does not affect TmPEO but does decrease the onset of crystallization upon cooling. PEO grafts result in fractionation of PE, decrease the melting point of PE and increase the undercooling for the onset of crystallization of PE.
PTEN and Ci-VSP Show Similar Phosphoinositide Binding Preferences

The Ciona intestinalis voltage sensor containing phosphatase (Ci-VSP) is a voltage dependent phosphatidylinositol phosphatase with two main domains, the voltage sensing domain (VSD) and the phosphatase domain (PD). Ci-VSP's PD bears homology with the phosphatase domain of the tumor suppressor protein PTEN (phosphatase and tensin homolog deleted chromosome 10). Recently, it has been proposed that the linker between the VSD and PD Ci-VSP constitute a Phosphoinositide Binding Motif (PBM). The PBM of Ci-VSP shares high homology with PTEN's N-terminal, which, in turn, is known to bind PI(4,5)P2 leading to an allosteric activation of PTEN. Similarly to the PBM of PTEN, we have found that a peptide representing the Ci-VSP's PBM (Ci-VSP240-271) binds PI(4,5)P2 significantly more strongly than other phosphatidyinositol bisphosphates. A Ci-VSP chimera created by replacing Arg 257 and Lys 258 with the amino acids found at the corresponding positions in the PTEN sequence, Gln 16 and Glu17, lead to a peptide that showed significantly reduced binding to PI(4,5)P2. While Ci-VSP240-271 exhibited a mixture of random and a-helical secondary structural elements, it was found that the chimeric Ci-VSP showed an increased b-sheet content. Molecular dynamics simulations were performed using the package NAMD and showed that the peptide does not form a helical structure and its charged residues interact in a pairwise fashion with PI(4,5)P2. Those pairs are form by R245 and R246, K252 and R253, and R254 and R257. Experimentally, the binding of the PBM has a great influence on the rate of return of the sensing charges. However, in a deletion mutant lacking the PD we observed that the PBM alone is not enough to limit the rate of return of the sensing currents. These observations strongly suggest that the binding of the PBM might be stabilized by the PD.
A Comparison of Two Tests for the Significance of a Mean Vector

Abstract Hotelling's T 2 procedure for testing the significance of a mean vector treats all variables symmetrically and may not be appropriate if the variables are of unequal importance. The step-down procedure (J. Roy 1958), possibly an appropriate alternative, is studied in this article. An underlying invariance structure is established and then used to develop a canonical form for studying the power functions of the two methods. A Monte Carlo experiment is conducted in this framework and conclusions are reported.
The impact of quantum theory on modern physics

The discovery of the quantum of action by Max Planck at the turn of our century was the beginning of one of the most fruitful and also most revolutionary developments in science. Rarely have our views regarding the basis of the properties and behavior of mat ter been changed and expanded as profundly as in the three decades following Planck's discovery. The subsequent discoveries of the quantization of energy in atoms, the existence of photons, the particlewave duality were in direct contradiction to the fundamental tenets of classical physics. I t became abundantly clear that the mechanics of systems of atomic size is based upon quite different laws than those which are observed to govern the behavior of macroscopic objects. A new foundation of mechanics was to be found in order to describe and understand atomic phenomena. I t took a quarter of a century before this task was accomplished. In the third decade of this century the paradoxes of quantum theory were solved and a new rational description of the dynamical behavior of small systems was established in terms of the new quantum mechanics. I t was discovered by a unique effort of a small group of physicists in a momentous development which took place essentially in the years t924 to t928. The leading spirits were Niels Bohr, Werner Heisenberg, Erwin Schroedinger, Max Born, Wotfgang Pauli, Louis DeBroglie, Paul Dirac, Pasqual Jordan and Hans Kramers. Never before have so few done so much in such a short time.
The Role of Glucagon Hypersecretion in the Pathogenesis of Hyperglycemia Following Acute Myocardial Infarction

In a group of nondiabetic patients, postinfarction hyperglycemia was found to be closely associated with high levels of plasma immunoreactive glucagon (IRG). It is proposed that, in certain cases, hyperglycemia following acute myocardial infarction may be related to a temporary and uninhibited rise in plasma glucagon levels, probably stimulated by the major stress of acute myocardial infarction.
Improved 3D triple-resonance NMR techniques applied to a 31 kDa protein

Recently proposed 3D triple-resonance techniques (I-5) make it possible to obtain sequential assignment of the backbone ‘H, 15N and 13C resonances in proteins that can be isotopically labeled with 13C and “N. Thi’s approach has been used successfully for a number of systems, including calmodulin ( 16.7 kDa) ( 1) , calmodulin complexed with a 26-residue peptide ( -20 kDa) (6), and the phospho-carrier protein IIIG’” ( 7) ( 18 kDa). All of these triple-resonance experiments rely on transfer of magnetization via heteronuclear one-bond Jcouplings and the sensitivity of the experiments depends strongly on the ratio of the size of the J coupling and the linewidths of the nuclei involved in the magnetization transfer process. Our original experiments were designed to minimize the number of RF pulses required for a particular pulse sequence, and thus to minimize the effect of pulse imperfections. Subsequent experience with these experiments has indicated that the effect of pulse imperfections is not as severe as originally expected, provided that pulses are properly calibrated. Hence, in order to optimize the experiments it is more important to minimize the relaxation of transverse magnetization by keeping the dephasing and rephasing delays as short as possible, especially for larger proteins. Here we demonstrate the applicability of three improved triple-resonance experiments to the study of interferon-y, a dimer with 134 residues per monomer and a total molecular weight of 3 1.4 kDa. Correlation of the amide proton and “N resonance with the intraresidue 13Ca can be obtained with an experiment known as HNCA (I, 2). Note that this experiment also provides connectivity to the Ca of the preceding residue, transferring coherence via the ’ JN-Ca coupling. Because ’ JN-Ca and ’ JNxn can be of comparable magnitude (8) it may not always be possible to distinguish intrafrom interresidue connectivities with this experiment. In contrast, the HN( CO)CA experiment (4) provides correlations exclusively to the Ca resonance of the preceding residue by relaying magnetization via the intervening carbonyl 13C spin. The HN( CO)CA experiment is closely related to the HNCO experiment, which correlates the amide ‘H and “N with the 13C of the preceding residue. In the present study of interferon-y, we employ modified versions of these experiments, using INEPT (9) instead of HMQC (10-12) type coherence transfers, and overlay the 13C15N dephasing period with a 15N evolution period
Detecting changes in simulated events using partial‐interval recording and momentary time sampling

In a series of three studies, we evaluated simulated data with reversal designs to determine whether partial-interval recording (PIR) and momentary time sampling (MTS) detected changes that were evident with continuous measures. The results from Study 1 showed that MTS with interval sizes up to 30 s detected most of the moderate and large changes in duration events and MTS with interval sizes up to 1 min detected most large changes in duration events. By comparison, PIR with 10-s intervals detected approximately half of all changes in duration events. The results of Study 2 showed that only 10-s PIR reliably detected most small, moderate, and large changes in frequency events. The results of Study 3 showed that PIR with 10-s intervals generated a relatively high percentage of false positives for duration events, whereas MTS did not. As a whole, the results support previous findings, but also provide new guidelines for the use of PIR and MTS. Copyright # 2008 John Wiley & Sons, Ltd.
Decision maker friendly approach for pricing software

Techniques for predicting computer software prices are of interest to researchers. This paper reviews and extends the earlier contributions of the authors to the field. It illustrates a new approach for predicting software prices. The illustrated approach is superior to previous approaches in two ways. First, the authors employ a unique factoring technique based on variable context that makes the final results easy to interpret and use. Second, the authors use variable transformations that have worked successfully in pricing computer hardware. The paper discusses the model construction, accuracy and results and helps decision makers better understand and control software prices.
Economic Estimates of Capital and Disaggregated Labour in Northern Europe, 1953–85

The literature is full of studies of production functions with capital and labour aggregate indices, mainly for the economies or manufacturing industries of the USA and Canada. Traditional Cobb‐Douglas and CES specifications treated aggregate labour on the assumption that heterogeneous labour categories were highly substitutable. Berndt and Christensen proposed that a consistent aggregate of diverse labour exists if certain Allen‐Uzawa partial elasticities of substitution (AUES, denoted σij, i, j = factor inputs) are equal.
Novel matrix based anterior cruciate ligament (ACL) regeneration

Among the five ligaments in the knee the anterior cruciate ligament (ACL) is among the most important for stability and also the most commonly injured. Due to a lack of vascularization, the ACL has poor healing potential, therefore moderate to severe damage warrants medical intervention. Ligaments are complex, highly organized tissues; they are longitudinally arranged with a great deal of order that begins at the molecular level and carries through to the tissue level. The components of the ligament and their location and orientation heavily influence the tissue's mechanical behavior. ACL replacements have faced a variety of limitations that prevented their extensive use, including implant fatigue or fraying of the device. In the face of these problems, investigators have begun to examine a variety of matrix based techniques to create options for ACL repair, replacement, and regeneration. This article will discuss ACL structure and mechanics, past replacement options and their limitations, and recent tissue engineered options for ACL repair. These techniques employ a wide variety of designs, materials, and methods to heal damaged ACL tissue or regenerate lost tissue in order to regain full ACL strength and mechanics.
Cyanoacrylates in pin retention.

I1 le oral examination of an ll-year-old girl revealed poor oral hygiene and extensive carious lesions. Previous dental experiences were limited because of the patient’s economic status. Her past medical history was negative. There was no history of pain or mobility. The lower first molar appeared devoid of healthy coronal tooth structure (Fig. 1). Radiographs indicated the pulpal chamber may not have been involved, and tests indicated pulp vitality.
Laing distal myopathy pathologically resembling inclusion body myositis

Mutations in MYH7 cause autosomal dominant Laing distal myopathy. We present a family with a previously reported deletion (c.5186_5188delAGA, p.K1729del). Muscle pathology in one family member was characterized by an inflammatory myopathy with rimmed vacuoles, increased MHC Class I expression, and perivascular and endomysial muscle inflammation comprising CD3+, CD4+, CD8+, and CD68+ inflammatory cells. Interestingly, this biopsy specimen contained TDP-43, p62, and SMI-31-positive protein aggregates typical of inclusion body myositis. These findings should alert physicians to the possibility that patients with MYH7 mutations may have muscle biopsies showing pathologic findings similar to inclusion body myositis.
Test of a liquid argon chamber with 20 μm RMS resolution

A measurement of the spatial resolution of a liquid-argon filled chamber was performed with minimum ionizing particles. Two multi-strip chambers with 20-{micro}m strip spacing operating in the ionization mode were used in the experiment. They perform in accordance with a simple model based on electron diffusion. An estimate of the amount of electron diffusion in liquid argon is given and the time jitter distribution has a FWHM of 200 ns. Under best conditions, the spatial resolution is better than 20 {micro}m rms with an efficiency of nearly 100%.
Gas Chromatographic Determination of Pentachlorophenol and Sodium Pentachlorophenate Residues in Fruits

SUMMARY A sensitive procedure for the determination of pentachlorophenol and sodium pentachlorophenate residues on fruits by electron-capture gas chromatography is described. In this method sodium pentachlorophenate is converted to pentachlorophenol in acid solution prior to analysis. The pentachlorophenol is then methylated with diazomethane, and is analyzed as the methyl ether by electron-capture gas chromatography. As little as 0.01 ppm can be detected, with recovery values ranging from 76 to 90%.
Properties and functions of glutathione reductase in plants

The assay and in vitro characterization of glutathione reductase (EC 1.6.4.2) is discussed. In vivo the H2O2-scavenging system in chloroplasts is the best documented role of reduced glutathione and glutathione reductase in plants. Similarly, redaction of H2O2, outside of the chloroplasts, requires glutathione and glutathione reductase; but the pathway, in terms of intermediates, is controversial. The notion that biological stress frequently causes cellular oxidation has lead to the suggestion that glutathione and glutathione reductase may play a role in stress resistance or tolerance mechanisms. The changes in glutathione reductase levels in response to low temperature, oxidative stress and drought are discussed.
Substances Adsorbed on the Fat Globules in Cream and their Relation to Churning. VI. Relation of the High-Melting Triglyceride Fraction to Butterfat and the “Membrane”

Summary High-melting triglyceride fractions of rather similar properties were obtained from butterfat, washed-cream buttermilk extracts, and washed-cream butter-serum extracts by crystallization from ethanol. Fractions twice crystallized from ethanol had iodine numbers of 5.0–7.1, saponification numbers of 198.8–204.0 and melting points of 52–53° C. Yields of this material from buttermilk extract were similar to those from butterfat solutions of like concentration but the yield from butter-serum extracts was invariably much greater. The significance of this finding has been discussed.
Porous capillary tubing waveguide for multigas sensing

This Letter reports simultaneous acetylene and carbon monoxide gas sensing by using a porous hollow-core waveguide. Compared to evanescent wave based gas sensors, the hollow-core waveguide can have a much better sensitivity because the majority of the light-wave energy propagating in the hollow core can interact directly with the gas molecules. The wall of the waveguide is made porous by the phase separating and leaching of the initial glass tubing. This allows the gas molecules to easily penetrate into the sensor providing the sensor with a very fast response time compared to other waveguide based gas sensors. A gas chamber system was constructed to simultaneously measure the presence of acetylene and carbon monoxide gases, and the testing results clearly indicate the high sensitivity and fast response time of this sensor.
Ultra Starvation Studied in the Spiral Orbit Tribometer

Spiral orbit tribometry has been used to study the coefficient of friction and electrical contact resistance of two vacuum lubricants in both the flooded system and the regime in which only a few nanoliters (μ g) of the lubricant are present, and the latter regime is designated here as ultrastarved. The experiment was supported by the extension to the ultrastarved regime of the recent analysis by Cann and coworkers of contact film thickness as a function of the lubricant volume in the heavily starved regime. The coefficients of friction in the ultrastarved regime were found to be the same as for the flooded system. The contact resistance was found to be zero at the beginning of the tests in the ultrastarved regime. The analysis by Cann and coworkers predicts the absence of a mobile liquid film at the contact in the ultrastarved regime. It is speculated that this persistence of lubrication into the ultrastarved regime is due to the retention of adherent lubricant molecules on the contacting surfaces and th...
The spectral discretization of transmission line system

The interconnections used in packaging of modern circuits introduce the delays that are comparable or even greater than the delays of gates. This causes the degradation of overall system performance. One may choose to solve the problem of delay by increasing the density of the system. This, however, introduces the problem of “crosstalk.” The analysis of delay and crosstalk in a system of interconnections requires the use of computer simulation. This paper introduces a very efficient and flexible time-domain analysis technique to predict the reflections and crosstalks. Numerical results show that this technique is indeed efficient and accurate in the transient analysis of general multiple coupled-line systems. The algorithm yields an equivalent linear hybrid n-port network for the interconnection system that facilitates the analysis of interconnections together with driving and receiving circuits with the aid of standard network analyzers like, for example, SPICE.
Propofol, seizures and generalized paroxysmal fast activity in the EEG

Propofol is a relatively new anesthetic agent used in outpatient surgery. Some investigators use it in the treatment of status epilepticus and in epilepsy surgery and have concluded that propofol has an anticonvulsant effect. Cases of seizure-like behaviors, myoclonus and opisthotonus following propofol anesthesia have been reported. Although rare, official warnings about this association have been issued. Different EEG abnormalities, and no abnormality, have been associated with propofol. We report a case of a healthy man who developed nonconvulsive seizures and generalized paroxysmal fast activity in his EEG following use of propofol for anesthesia.
Rotenone selectively kills serotonergic neurons through a microtubule-dependent mechanism

As a major co-morbidity of Parkinson's disease (PD), depression is associated with the loss of serotonergic neurons. Our recent study has shown that midbrain dopaminergic neurons are particularly vulnerable to microtubule-depolymerizing agents including rotenone, an environmental toxin linked to PD. Here we show that rotenone also selectively killed serotonergic neurons in midbrain neuronal cultures. Its selective toxicity was significantly decreased by the microtubule-stabilizing drug taxol and mimicked by microtubule-depolymerizing agents such as colchicine and nocodazole. Microtubule depolymerization induced by rotenone or colchicine caused vesicle accumulation in the soma and killed serotonergic neurons through a mechanism dependent on serotonin metabolism in the cytosol. Blocking serotonin synthesis or degradation, as well as application of antioxidants, significantly reduced the selective toxicity of rotenone or colchicine. Inhibition of vesicular sequestration of serotonin exerted a selective toxicity on serotonergic neurons that was mitigated by blocking serotonin metabolism. Over-expression of parkin, a protein-ubiquitin E3 ligase that strongly binds to microtubules, greatly attenuated the selective toxicity of rotenone or colchicine. The protective effects of parkin were abrogated by its PD-linked mutations. Together, our results suggest that rotenone and parkin affect the survival of serotonergic neurons by impacting on microtubules in opposing manners.
Detection of IUPAC and IUPAC-like chemical names

Motivation: Chemical compounds like small signal molecules or other biological active chemical substances are an important entity class in life science publications and patents. Several representations and nomenclatures for chemicals like SMILES, InChI, IUPAC or trivial names exist. Only SMILES and InChI names allow a direct structure search, but in biomedical texts trivial names and Iupac like names are used more frequent. While trivial names can be found with a dictionary-based approach and in such a way mapped to their corresponding structures, it is not possible to enumerate all IUPAC names. In this work, we present a new machine learning approach based on conditional random fields (CRF) to find mentions of IUPAC and IUPAC-like names in scientific text as well as its evaluation and the conversion rate with available name-to-structure tools. Results: We present an IUPAC name recognizer with an F1 measure of 85.6% on a MEDLINE corpus. The evaluation of different CRF orders and offset conjunction orders demonstrates the importance of these parameters. An evaluation of hand-selected patent sections containing large enumerations and terms with mixed nomenclature shows a good performance on these cases (F1 measure 81.5%). Remaining recognition problems are to detect correct borders of the typically long terms, especially when occurring in parentheses or enumerations. We demonstrate the scalability of our implementation by providing results from a full MEDLINE run. Availability: We plan to publish the corpora, annotation guideline as well as the conditional random field model as a UIMA component. Contact: roman.klinger@scai.fraunhofer.de
Management of Breast Cancer in the Genome Era

The genomic era has been characterized by an exponential increase in the number of targets in the management of breast cancer. Prognostic profiling has helped to determine which tumors are more likely to be associated with poor disease-free survival. Gene expression profiles are being studied in order to improve predictions of response and toxicity. Epigenetics is being evaluated for its ability to influence estrogen receptor expression. However, these fields require further validation. This review discusses the advances in the management of breast cancer through genomic evaluation.
Glutamate carboxypeptidase activity in human skin biopsies as a pharmacodynamic marker for clinical studies

Background Glutamate excitotoxicity is thought to be involved in the pathogenesis of neurodegenerative disease. One potential source of glutamate is N-acetyl-aspartyl-glutamate (NAAG) which is hydrolyzed to glutamate and N-acetyl-aspartate (NAA) in a reaction catalyzed by glutamate carboxypeptidase (GCP). As a result, GCP inhibition is thought to be beneficial for the treatment of neurodegenerative diseases where excess glutamate is presumed pathogenic. Both pharmacological and genetic inhibition of GCP has shown therapeutic utility in preclinical models and this has led to GCP inhibitors being pursued for the treatment of nervous system disorders in human clinical trials. Specifically, GCP inhibitors are currently being developed for peripheral neuropathy and neuropathic pain. The purpose of this study was to develop a pharmacodynamic (PD) marker assay to use in clinical development. The PD marker will determine the effect of GCP inhibitors on GCP enzymatic activity in human skin as measure of inhibition in peripheral nerve and help predict drug doses required to elicit pharmacologic responses.
A distributed approach to topology-aware overlay path monitoring

Path probing is essential to maintain an efficient overlay network topology. However, the cost of complete probing can be as high as O(n/sup 2/), which is prohibitive in large-scale overlay networks. Recently we proposed a method that trades probing overhead for inference accuracy in sparse networks such as the Internet. The method uses physical path information to infer path quality for all of the n/spl times/(n-1) overlay paths, while actually probing only a subset of the paths. We propose and evaluate a distributed approach to implement this method. We describe a minimum diameter, link-stress bounded overlay spanning tree, which is used to collect and disseminate path quality information. All nodes in the tree collaborate to infer the quality of all paths. Simulation results show this approach can achieve a high-level of inference accuracy while reducing probing overhead and balancing link stress on the spanning tree.
THE PERSONAL COMPUTER AS A LABORATORY INSTRUMENT–PART II

Multifunction I/O boards are a very appropriate way to transform the personal computer into a laboratory instrument for data acquisition and test control. They offer speed and flexibility, and convenience for the engineer or programmer. Caution must be exercised in not only choosing a board appropriate for the task but also in choosing a board which can be made to do the task through programming flexibility. There is no single board or manufacturer which will suit all the potential test configurations which will arise, but some boards and their software support are more appropriate than others. The list of suppliers, though not all inclusive, does represent a spectrum of products.
A Review of Clinical Practice Guidelines for Palliative Nursing (FR457-B)

Systemic Review Background: Clinical practice guidelines are meant to provide evidence-based recommendations that can optimize care. While the National Consensus Guidelines for Quality Palliative Care have provided an excellent foundation of understanding for the interdisciplinary practice of palliative care, clear practice guidelines for nurses can improve patient and family outcomes and guide nursing education. Practice guidelines concerning palliative care have been developed by various organizations and groups, but it has not been clear which of these are relevant to the clinical practice of palliative nursing. Aims: The aims of this review were to (1) Identify existing clinical practice guidelines with relevance to the practice of palliative
The slow and fast life histories of early birds and night owls: their future- or present-orientation accounts for their sexually monogamous or promiscuous tendencies

Abstract In this study we tested the hypothesis that inter-individual variation in morningness–eveningness (i.e., chronotype) is associated with variation in a composite measure of life history (the mini-K) such that morning-types (i.e., early birds) exhibit traits typically associated with slow life histories while evening-types (i.e., night owls) exhibit traits typically associated with fast life histories. In addition, we tested the hypothesis that time perspective may be one of the psychological mechanisms mediating the relationship between chronotype and socio-sexuality. Study participants were 95 heterosexual young men, most of whom were university students. Chronotype, life-history traits, socio-sexuality, and time perspective were assessed with well-established self-report measures. Variations in chronotype and in life-history traits were significantly associated in the direction predicted by our hypothesis. Consistent with our second hypothesis, time perspective emerged as a significant mediator of the association between chronotype and socio-sexuality so that the future orientation of morning-types was associated with their long-term mating orientation and relatively low sexual experience, while the present orientation of evening-types was associated with their short-term mating orientation and greater sexual experience. Our study provides the first evidence that variation in chronotype may be adaptive and elucidates one of the psychological mechanisms underlying the life history and reproductive strategies of male early birds and night owls.
''A Great Complication of Circumstances'' - Darwin and the Economy of Nature

In 1749, Linnaeus presided over the dissertation “Oeconomia Naturae,” which argued that each creature plays an important and particular role in nature’s economy. This phrase should be familiar to readers of Darwin, for he claims in the Origin that “all organic beings are striving, it may be said, to seize on each place in the economy of nature.” Many scholars have discussed the influence of political economy on Darwin’s ideas. In this paper, I take a different tack, showing that Darwin’s idea of an economy of nature stemmed from the views of earlier naturalists like Linnaeus and Lyell. I argue, in the first section of the paper, that Linnaeus’ idea of oeconomia naturae is derived from the idea of the animal economy, and that his idea of politia naturae is an extension of the idea of a politia civitatis. In the second part, I explore the use of the concept of stations in the work of De Candolle and Lyell – the precursor to Darwin’s concept of places. I show in the third part of the paper that the idea of places in an economy of nature is employed by Darwin at many key points in his thinking: his discussion of the Galapagos birds, his reading of Malthus, etc. Finally, in the last section, I demonstrate that the idea of a place in nature’s economy is essential to Darwin’s account of divergence. To tell his famous story of divergence and adaptation, Darwin needed the economy of nature.
Ethnic differences in diffuse noxious inhibitory controls.

Abstract Substantial evidence indicates that the experience of both clinical and experimental pain differs among ethnic groups. Specifically, African Americans generally report higher levels of clinical pain and greater sensitivity to experimentally induced pain; however, little research has examined the origins of these differences. Differences in central pain-inhibitory mechanisms may contribute to this disparity. Diffuse noxious inhibitory controls (DNIC), or counterirritation, is a phenomenon thought to reflect descending inhibition of pain signals. The current study assessed DNIC in 57 healthy young adults from 2 different ethnic groups: African Americans and non-Hispanic whites. Repeated assessments of the nociceptive flexion reflex (NFR) as well as ratings of electrical pain were obtained before, during, and after an ischemic arm pain procedure (as well as a sham procedure). The DNIC condition (ie, ischemic arm pain) produced substantial reductions in pain ratings as well as electrophysiologic measures of the NFR for all participants when compared with the sham condition ( P P = .02), whereas ethnic groups showed comparable reductions in NFR. The findings of this study suggest differences in endogenous pain inhibition between African Americans and non-Hispanic whites and that additional research to determine the mechanisms underlying these effects is warranted. Perspective This study adds to the growing literature examining ethnic differences in experimental pain perception. Our data suggest that these variations may be influenced by differences in descending inhibition.
Light phase-restricted feeding slows basal heart rate to exaggerate the type-3 long QT syndrome phenotype in mice.

Long QT syndrome type 3 (LQT3) is caused by mutations in the SCN5A-encoded Nav1.5 channel. LQT3 patients exhibit time of day-associated abnormal increases in their heart rate-corrected QT (QTc) int...
Economic modeling comparing trauma and general surgery reimbursement

Abstract Background The viability of trauma care as a surgical subspecialty is continually challenged by economic pressures related to reimbursement and opportunity costs. Methods The literature was examined for articles focused on economic implications of a trauma focused surgical practice. Economic forecasting techniques were applied using a recalculating spreadsheet to examine charge and revenue generation comparing the effects of numerous variables affecting a trauma or general surgical service. Results Elective general surgery practices derive the majority of revenues from procedural services, whereas trauma practices derive the majority of revenues from evaluation and management. Only centers with high admission volume can expect trauma surgeons to cover salary and expenses, predictably in association with high opportunity costs. Conclusion The differences in time, effort, and patient volume required for a trauma surgeon to generate revenues comparable to an elective practice are dramatic. The current system creates disincentives for surgeons to participate in trauma care.
Visual Analysis of Mutual Fund Performance

Mutual funds are probably the most important investment instruments for investors. Their performance is mainly affected by their characteristics, such as asset size, turnover and fee structure. It is thus of the investors' highest priorities to understand the relation between fund performance and these properties. Typically, financial researchers use the linear regression technique to statistically assess the relation from massive fund performance data. Unfortunately, the prevailing methods may be confounded by the existence of on-linearity and outliers, and give conflicting conclusions. In this paper, we propose a visualization-based method to improve the mutual fund analysis, where a new visual analytical tool, the density-based distribution map, is applied. The new visual representations greatly help to understand the critical relations, reveal the deficiency of current analytical algorithms,and support mutual funds selection. The tool is used to perform an expert financial analysis, and establish a fund selection strategy from a real-world database of the US stock funds. Our method gains the admiration and support from professionals in the finance field, they embrace it as a potential investment analysis tool for mutual fund managers, financial planners, and investors.
New Directions in Electrical Engineering Education

Virtually all of us believe in the great importance of physics in engineering curricula and have fought for years to develop a strong and modern physical basis for instruction in engineering. From our observations, the basic question is no longer seriously disputed; the idea is generally accepted and only the details of local implementation seem to remain. If this is so, why does discussion continue on what should be a dead issue? Why do we continue to beat an academic "dead horse?" In searching for the answer, we have come to some disturbing conclusions which, theoretically, place the entire issue in a different perspective, establishing new directions in electrical engineering education.