cssi/SciSciGPT-SciSciNet huggingface dataset:
Interrupted ongoing behaviour in two species of vole (Microtus agrestis and Clethrionomys britannicus). II. Extended analysis of motivational variables underlying fleeing and grooming behaviour

Abstract Experiments were designed to examine two previously proposed variables: (a) an ‘activity tendency’ which results in increased probability of fleeing; (b) an ‘optimal arousal’ range in which grooming is most likely to occur. Wild-trapped Microtus agrestis and Clethrionomys britannicus were individually housed and tested in the previously employed experimental alley. The probability of fleeing behaviour was greatly increased when overt locomotion was either concurrent with or ceased within 10 sec of the experimental disturbance. The concept of a temporarily persisting ‘activity tendency’ which in itself affects fleeing was supported. Amphetamine increased fleeing and Nembutal decreased fleeing to an extent that could not be accounted for solely in terms of current or recently ceased locomotion. Differences between species and cover conditions were equivocal, perhaps due to the high tendency of individually housed animals to flee. Two main techniques for studying the previously defined ‘optimal arousal’ model for grooming were (1) to examine integration of home pen cover plus amphetamine and Nembutal with species differences in grooming, (2) attempt to manipulate ‘arousal’ over a wide range with the two drugs. Cover and 0·8 mg per kg amphetamine produced more grooming in Microtus while no cover and 15 mg per kg Nembutal produced more grooming in Clethrionomys, as predicted from the ‘arousal’ model. Further, the drug and cover inputs combined in their effect. Each species showed an overall non-linear relationship between drug dose and grooming as expected from the model. Certain inconsistencies with the model were also noted in the present experiments, however, and the possibility that both ‘arousal’ and ‘conflict’ models are necessary is discussed. The increase in grooming intensity was again noted, particularly under amphetamine, as was the increased probability and vigour of other simple motor patterns with this drug. Problems of integration of multiple inputs with patterned outputs are discussed further.
Delta Flow: An Accurate, Reliable System for Detecting Kicks and Loss of Circulation During Drilling

A system to monitor drilling-fluid flow rate has been developed that detects kicks and lost returns in floating, fixed-platform, and land-base drilling operations. The system uses flowmeters that monitor the flow rates of drilling fluids entering the borehole through the standpipe and leaving the well through the return flowline. These readings are processed in a computer-based, data-acquisition system to form a filtered delta-flow signal that identified the occurrence of downhole fluid gains or losses. The system is designed to trip an alarm when a gain or loss exceeds 25 gal/min (1.6 dm/sup 3//s), even in a floating drilling environment. This sensitivity will generally keep gains or losses to less than 5 bbl (0.8 m/sup 3/).
Optimality analysis of energy-performance trade-off for server farm management

A central question in designing server farms today is how to efficiently provision the number of servers to extract the best performance under unpredictable demand patterns while not wasting energy. While one would like to turn servers off when they become idle to save energy, the large setup cost (both, in terms of setup time and energy penalty) needed to switch the server back on can adversely affect performance. The problem is made more complex by the fact that today's servers provide multiple sleep or standby states which trade off the setup cost with the power consumed while the server is 'sleeping'. With so many controls, finding the optimal server farm management policy is an almost intractable problem - How many servers should be on at any given time, how many should be off, and how many should be in some sleep state? In this paper, we employ the popular metric of Energy-Response time Product (ERP) to capture the energy-performance trade-off, and present the first theoretical results on the optimality of server farm management policies. For a stationary demand pattern, we prove that there exists a very small, natural class of policies that always contains the optimal policy for a single server, and conjecture it to contain a near-optimal policy for multi-server systems. For time-varying demand patterns, we propose a simple, traffic-oblivious policy and provide analytical and empirical evidence for its near-optimality.
Inducible expression of REP1 causes inducible expression of the 2 micron circle stability system

The yeast plasmid, 2 micron circle, encodes a stability system consisting of the plasmid replication origin, a cis-active locus designated REP3 and two transactive functions — the products of the REP1 and REP2 genes. We have constructed 2 micron circle derivatives in which the expression of the REP1 gene is placed under the control of the yeast GAL10 promoter. We show that in such plasmids the stability-system is inducible, being turned off by glucose and turned on by galactose. Further, our results unequivocally demonstrate that, of the two potentialin-frame ATG codons at which REP1 translation might initiate (as inferred from the 2 micron circle DNA sequence and from the cap site of the major REP1 transcript), the upstream ATG is dispensable without affecting REP1 function. We also illustrate here a simple and general method for constructing in vivo in yeast 2 micron circle analogs which contain desired alterations within specific regions of the 2 micron circle genome.
Spectral sensitivity optimization of color image sensors considering photon shot noise: four-channel sensor models

Four channel sensors were evaluated with a image sensor model and their performance was compared with three channel sensors considering both color reproduction accuracy and photo shot noise. When noise was not considered, a sensor with usual RGB plus an additional channel which resided between G and B was the best. But when the emphasis was on noise, a sensor with B, R and two Gs was the best because reducing noise of G should be effective in reducing noise of all L*a*b* components. Bayer color filter array (CFA) samples twice density of G than R or B. This CFA is considered to be efficient in resolution but the result suggests it is also efficient in SNR. Comparing to three channel sensors, the four channel sensors were better in color reproduction but worse in noise. An image preference model proposed by Kuniba and Berns was used to evaluate them and it was shown that neither one was superior than the other.
Synthesis of carbon‐14 labelled piritrexim ‐ a potential anticancer agent

Piritrexim 1(2,4-diamino-6-(2,5-dimethoxybenzyl)-5-methylpyrido[2,3-d]-pyrimidine) was synthesized in the [14C]-labelled form with specific activity 50.8 mCi/mmol suitable for drug metabolism, transport, dispostion and mechanism of action studies. The synthetic sequence involved synthesis of the novel 2-bromo-5-(2,5-dimethoxybenzyl)-4-methyl-3-pyridinecarbonitrile and condensation of this compound with [14C]-guanidine hydrochloride. The radiochemical purity was >98%.
Multistage tandem mass spectrometry of anionic phosphatidylcholine lipid adducts reveals novel dissociation pathways

Abstract The gas-phase fragmentation reactions of various anionic adducts of phosphatidylcholine lipids have been examined by electrospray ionization and multistage tandem mass spectrometry (MSn) in a linear quadrupole ion trap mass spectrometer. The MS/MS and MSn fragmentation reactions of the anionic adducts were found to be highly dependent on the identity of the anions (A). Consistent with previous reports, MS/MS of phosphatidylcholine lipid ions formed by anionic adduction with formate, acetate and chloride resulted in a dominant product ion corresponding to the loss of (A + CH3) from the [M + A]− precursor ions. In contrast, MS/MS of other anion adducted precursor ions gave rise to multiple products, including [M + A (A + CH3)]−, [M + A (AH)]−, [M + A (AH + CH3)]−, [M + A (AH + (CH3)3N)]−, [M + A (A + (CH3)3NCHCH2)]− and [M + A (CH3)3N)]−. In order to gain evidence for the structures of these product ions, and the mechanisms by which they were formed, each of the products formed by MS/MS were subjected to further analysis by MS3 and MS4. The MS/MS and MSn fragmentation reactions of several deuterium isotope labeled phosphatidylcholine lipid standards, as well as authentic or structurally analogous lipid standards corresponding to the proposed product ion structures were also examined to gain evidence to support the proposed mechanisms. The results from this study indicate that great care must be taken to control the identity of the anions employed during lipid isolation, purification and separation, in order to allow the development and application of sensitive and robust neutral loss scan methods for mass spectrometry based lipid identification and quantitative analysis.
Non-aqueous solvation of n-octanol and ethanol: spectroscopic and computational studies.

Raman spectroscopy was used to examine the interactions of the free O−H bonds in n-octanol and ethanol with the organic solvents carbon tetrachloride (CCl4), cyclohexane, and benzene. These spectra reveal that the solvents CCl4 and cyclohexane have a small effect on the free O−H peak of alcohols, whereas benzene as a solvent significantly red-shifts the free O−H band. Calculated spectra were generated via MP2/6-31G* calculations and the B3LYP/6-31+G**//MP2/6-31G*-derived Boltzmann populations of each ethanol complex and are consistent with the experimental results. Additional spectra were calculated using Boltzmann populations derived from single-point energies at the polarizable continuum model (PCM) level with the B3LYP/6-31+G** level of theory to take overall solvent effects into account, and these simulated spectra are also largely consistent with the experimental results. Analysis of the computational results reveals a lengthening of the O−H bond from the O−H interaction with the delocalized electron...
Electrode Misconnection, Misplacement, and Artifact

The emergency physician (EP) examines the electrocardiogram (ECG) looking for evidence of normalcy and for signs of ischemia, dysrhythmia, and many other variations of normal, such as are described in this issue. An under appreciated cause of ECG abnormality is electrode misconnection and misplacement. This occurs when the ECG electrode is mistakenly connected to the wrong part of the body (electrode misconnection, as can occur most commonly with the limb electrodes, I, II, III, aVR, aVL, and aVF) or is placed improperly on the body (electrode misplacement, such as can occur most easily with the precordial electrodes, V1–V6). Knowledge of the common patterns of electrode misconnection and misplacement lead to the ready recognition of this phenomenon in everyday practice. Using recordings from four limb electrodes (RA or right arm, LA or left arm, RL or right leg, and LL or left leg), six frontal plane electrocardiographic tracings, or leads, are generated. An understanding of limb electrode misconnection begins with a review of the derivation of the three limb leads (I, II, and III) and the three augmented leads (aVR, aVL, and aVF) (Fig. 1). In the horizontal plane, six precordial electrodes (V1–V6) yield six electrocardiographic leads (V1–V6); although they too can be misconnected, the pitfalls of right/left and arm/leg reversal do not apply here. Recording problems with the precordial electrodes more significantly are caused by improper positioning of the individual electrodes on the body surface because of anatomic variation. Common examples of limb electrode reversal and precordial electrode misconnection and misplacement are described.
Nonlinear absorption of photons in biological molecules: initial studies of melanin

Based on the mechanisms of sequential two-photon absorption in biological molecules, a theoretical model is proposed for the absorption of light in melanin. To test this model, melanin samples were studied using the collinear photothermal deflection spectroscopy (PDS), with an He-Ne laser and an Argon-Krypton ion laser to provide two simultaneously exciting wavelengths. It is found that melanin samples have a strong decay in amplitude of the photothermal signal, in contrast to a reference India ink whose photothermal signal is stable. The power dependence of the amplitude of the photothermal signal is also found to exhibit a departure from linearity at higher power densities for a melanin sample. Simultaneous exposure of the same sample to He-Ne and Argon-Krypton ion laser irradiation produces a signal which is significantly less than that expected from the sum of the signals obtained from using each laser alone. These results are explained with a modification of the sequential two-photon absorption process, which involves a conversion of the photon energy to a non- thermal form such as photochemical energy.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
AN OIL-FIRED FURNACE FOR THE PLANT LABORATORY

Description of Furnace.—This is an iron-encased furnace with 1½-inch asbestos insulation. The chamber is 21 inches square by 20 inches high and will hold 14 bricks on end. Operation of Furnace.—This requires from 16 to 20 gallons of fuel oil per heat of high temperature for a period of five hours. Pre-heated air is supplied by a No. 4 Blower running 3000 R.P.M. delivered through a 3-inch pipe.
An Automatic Injection Device for Precise Cement Delivery During Osteoporotic Bone Augmentation

Augmentation of osteoporotic bone with polymethylmethacrylate (PMMA) bone cement has been shown to be effective in reducing the risk of bone fracture. Injection of the highly viscous bone cement, however, is challenging mainly due to high injection forces required to maintain the nominal injection rates. Also, effective placement of the cement requires precise planning and execution. We are developing a surgical workstation for planning and executing proximal femur augmentation. As a crucial part of the framework, we have designed and fabricated a prototype automatic injection device that provides the substantial forces while maintaining the planned injection rates. Design parameters were determined based on the criteria available in the literature and our preliminary tests. Intended features for the device included high injection force capability, precisely controllable injection and ease of use. A number of calibration experiments were performed to ensure that the device meets the intended criteria. The device can be quickly set up before the surgical operation and can operate in manual or automatic placement configurations. The automatic injection device can also be used for a range of other orthopaedic applications involving direct augmentation of the bones or screws fixated in the bones.Copyright © 2011 by ASME
Effects of esomeprazole magnesium on nonsteroidal anti-inflammatory drug gastropathy

It has been proposed that tissue damage induced by nonsteroidal anti-inflammatory drugs is related to increased tissue free radical production with antioxidant depletion. We have shown that esomeprazole increases gastric total antioxidant capacity in mice and, therefore, hypothesized that the protective effect of esomeprazole during treatment with a nonsteroidal anti-inflammatory drug is related to increased gastric antioxidant capacity and decreased tissue free radical production. A/J mice received one of four treatments by daily gavage: saline in vehicle (control), indomethacin, esomeprazole, or indomethacin and esomeprazole. After 10 days, all mice were sacrificed and validated assays were used to measure gastric total antioxidant capacity, lipid peroxide levels, and myeloperoxidase activity. Indomethacin-treated mice developed weight loss and melena. No mice receiving indomethacin and esomeprazole died, but the death rate while receiving indomethacin was 38% (χ2, P = 0.05). Gastric lipid peroxide levels increased in mice receiving indomethacin treatment compared to treatment with esomeprazole and indomethacin (P = 0.03). There was a strong trend (P = 0.08) toward increased gastric total antioxidant capacity in mice receiving esomeprazole and indomethacin compared to mice receiving indomethacin. Gastric myeloperoxidase activities were not different among the four groups. Esomeprazole significantly improved survival in mice that received indomethacin, reduced free radical production, as estimated by lipid peroxide levels, and appeared to increase gastric total antioxidant capacity. The mechanisms for the beneficial effects of esomeprazole in the treatment of gastropathy are more complex than previously thought.
Food of and Habitat Use by Juveniles of Species of Micropterus and Morone in a Southwestern Reservoir

Abstract We determined food of and habitat use by juvenile largemouth bass Micropterus salmoides, spotted bass Micropterus punctulatus, striped bass Morone saxatilis, and white bass Morone chrysops over a 6-year period (1981–1986) in Lake Texoma, Oklahoma–Texas. Largemouth bass, spotted bass, and white bass are native to the river basin and reservoir, whereas striped bass are introduced. Diet overlap (based on numbers or weight) was highest between the two species of Morone and between the two species of Micropterus, and was also substantial (if based on prey weight) between largemouth bass and striped bass and between largemouth bass and white bass. Diet overlap between field-caught striped bass and largemouth bass was sufficiently high to suggest potential trophic competition between juveniles, but the two species occupied substantially different habitats as juveniles. Spatial segregation seemed sufficient to ameliorate potential competition between the latter two species. A laboratory experiment to tes...
Long-term outcomes in patients with metastatic melanoma vaccinated with melanoma peptide-pulsed CD34+ progenitor-derived dendritic cells

Between March 1999 and May 2000, 18 HLA-A*0201(+) patients with metastatic melanoma were enrolled in a phase I trial using a dendritic cell (DC) vaccine generated by culturing CD34(+) hematopoietic progenitors. This vaccine includes Langerhans cells. The DC vaccine was loaded with four melanoma peptides (MART-1/MelanA, tyrosinase, MAGE-3, and gp100), Influenza matrix peptide (Flu-MP), and keyhole limpet hemocyanin (KLH). Ten patients received eight vaccinations, one patient received six vaccinations, one patient received five vaccinations, and six patients received four vaccinations. Peptide-specific immunity was measured by IFN-gamma production and tetramer staining in blood mononuclear cells. The estimated median overall survival was 20 months (range: 2-83), and the median event-free survival was 7 months (range: 2-83). As of August 2005, four patients are alive (three patients had M1a disease and one patient had M1c disease). Three of them have had no additional therapy since trial completion; two of them had solitary lymph node metastasis, and one patient had liver metastasis. Patients who survived longer were those who mounted melanoma peptide-specific immunity to at least two melanoma peptides. The present results therefore justify the design of larger follow-up studies to assess the immunological and clinical outcomes in patients with metastatic melanoma vaccinated with peptide-pulsed CD34-derived DCs.
A thermodynamic and biomechanical theory of cell adhesion. Part I: General formulism.

The equilibrium thermodynamics calculus of cell adhesion developed by Bell et al. (1984, Biophys. J. 45 , 1051–1064) has been extended to the general non-equilibrium case. In contrast to previous models which could only compute the end results of equilibrium states, the present theory is able to calculate the kinetic process of evolution of adhesion, which may or may not approach towards equilibrium. Starting from a basic constitutive hypothesis for Helmholtz free energy, equations of balance of normal forces, energy balance at the edge of the contact area and rate of entropy production are derived using an irreversible thermodynamics approach, in which the restriction imposed by the Second Law of Thermodynamics takes the place of free energy minimization used by Bell et al. (1984). An explicit expression for adhesion energy density is derived for the general transient case as the difference of the usable work transduced from chemical energy liberation from bond formation of specific crosslinking molecules and the repulsive potential of non-specific interactions. This allows the energy balance to be used as an independent boundary equation rather than a practical way of computing the adhesion energy. Jump conditions are obtained from the conservation of crosslinking molecules across the edge of adhesion region which is treated as a singular curve. The bond formation and lateral motion of the crosslinking molecules are assumed to obey a set of reaction-diffusion equations. These equations and the force balance equation within the contact area, plus the jump conditions and the energy balance equation at the edge form a well-posed moving boundary problem which determines the propagation of the adhesion boundary, the separation distance between the two cell membranes over the contact area as well as the distributions of the crosslinking molecules on the cell surfaces. The behavior of the system depends on the relative importance of virtual convection, lateral diffusion and bond formation of the crosslinking molecules at the edge of the adhesion region, according to which two types of rate limiting cases are discussed, viz , reaction-limited and diffusion-limited processes.
Sequential Voluntary Cough and Aspiration or Aspiration Risk in Parkinson’s Disease

Background Disordered swallowing, or dysphagia, is almost always present to some degree in people with Parkinson’s disease (PD), either causing aspiration or greatly increasing the risk for aspiration during swallowing. This likely contributes to aspiration pneumonia, a leading cause of death in this patient population. Effective airway protection is dependent upon multiple behaviors, including cough and swallowing. Single voluntary cough function is disordered in people with PD and dysphagia. However, the appropriate response to aspirate material is more than one cough, or sequential cough. The goal of this study was to examine voluntary sequential coughing in people with PD, with and without dysphagia.
Simultaneous averaging of epileptic discharges in 14 channels: A computer technique

Abstract A computer technique for the simultaneous averaging of epileptic discharges in 14 channels is presented. It is based on direct visual identification of reference points within the considered electric events and on the computation of their average using selected samples stored after A-D conversion. It can be utilized in studies concerned with the morphology of epileptic spikes and their temporal relationships among different leads.
Database searches for binding sites.

In their Report “Identification of a coordinate regulator of interleukins 4, 13, and 5 by cross-species sequence comparisons” (7 Apr., p. [136][1]), G. G. Loots and colleagues identify conserved noncoding sequences (CNSs) in orthologous regions of the interleukin (IL)-4/13/5 locus of several
A 2.2 Å resolution structure of the USP7 catalytic domain in a new space group elaborates upon structural rearrangements resulting from ubiquitin binding.

A sparse-matrix screen for new crystallization conditions for the USP7 catalytic domain (USP7CD) led to the identification of a condition in which crystals grow reproducibly in 24-48 h. Variation of the halide metal, growth temperature and seed-stock concentration resulted in a shift in space group from P21 with two molecules in the asymmetric unit to C2 with one molecule in the asymmetric unit. Representative structures from each space group were determined to 2.2 A resolution and these structures support previous findings that the catalytic triad and switching loop are likely to be in unproductive conformations in the absence of ubiquitin (Ub). Importantly, the new structures reveal previously unobserved electron density for blocking loop 1 (BL1) residues 410-419. The new structures indicate a distinct rearrangement of the USP7 BL1 compared with its position in the presence of bound Ub.
An Introduction To "America's Energy Supply" by C.P. Steinmetz

“America’s Energy Supply” was written by C. P. Steinmetz (Fig. 1), who was president of the American Institute of Electrical Engineers (AIEE) in 1901 and a partner with Edison in the early days of the General Electric Company. This paper addresses America’s energy supply from the beginning of the twentieth century. There are three themes in this paper: efficiency and effectiveness of coal and hydrogeneration, cogeneration (to increase efficiency), and solar energy. In the 100-year period between the early 1800’s and early 1900’s, there was a steady increase in coal production from year to year, which experienced almost no interruptions from most of the catastrophic political and industrial convulsions of the nineteenth century, namely, the Civil War and the industrial panic of the 1890’s. Almost 80 years ago, when this paper was written, the use of coal was increasing at a rate of 6‐10% per year, which led the author to predict that at that rate, 10 000 million tons of coal would be produced in the United States in 1958. But alternate sources of energy were quickly gaining acceptance after World War II. Even though the prediction did not materialize, primarily because of the advent of natural gas and oil as preferred energy sources, coal production has indeed steadily increased since then, reaching just over 1 billion tons in 1996, one-tenth of Steinmetz’s prediction for 1958. As coal and hydropower were used to supply the country’s electric power needs at the time, one obvious question was what fuel source could be used to keep up with the growing demand for electricity. Hydropower, at its fullest potential of 230 million kW-h, could supply the total energy needs of the early twentieth century. That meant that as the energy demands grew, and the share of coal in the “generation mix” began to fall, the reliance on hydropower could not be total. This was probably the strongest argument for efforts to increase the efficiency of the methods for using coal. In the early 1900’s, the average efficiency of coal
The GLFG regions of Nup116p and Nup100p serve as binding sites for both Kap95p and Mex67p at the nuclear pore complex.

Our previous studies have focused on a family ofSaccharomyces cerevisiae nuclear pore complex (NPC) proteins that contain domains composed of repetitive tetrapeptide glycine-leucine-phenylalanine-glycine (GLFG) motifs. We have previously shown that the GLFG regions of Nup116p and Nup100p directly bind the karyopherin transport factor Kap95p during nuclear protein import. In this report, we have further investigated potential roles for the GLFG region in mRNA export. The subcellular localizations of green fluorescent protein (GFP)-tagged mRNA transport factors were individually examined in yeast cells overexpressing the Nup116-GLFG region. The essential mRNA export factors Mex67-GFP, Mtr2-GFP, and Dbp5-GFP accumulated in the nucleus. In contrast, the localizations of Gle1-GFP and Gle2-GFP remained predominantly associated with the NPC, as in wild type cells. The localization of Kap95p was also not perturbed with GLFG overexpression. Coimmunoprecipitation experiments from yeast cell lysates resulted in the isolation of a Mex67p-Nup116p complex. Soluble binding assays with bacterially expressed recombinant proteins confirmed a direct interaction between Mex67p and the Nup116-GLFG or Nup100-GLFG regions. Mtr2p was not required for in vitro binding of Mex67p to the GLFG region. To map the Nup116-GLFG subregion(s) required for Kap95p and/or Mex67p association, yeast two-hybrid analysis was used. Of the 33 Nup116-GLFG repeats that compose the domain, a central subregion of nine GLFG repeats was sufficient for binding either Kap95p or Mex67p. Interestingly, the first 12 repeats from the full-length region only had a positive interaction with Mex67p, whereas the last 12 were only positive with Kap95p. Thus, the GLFG domain may have the capacity to bind both karyopherins and an mRNA export factor simultaneously. Taken together, our in vivo and in vitro results define an essential role for a direct Mex67p-GLFG interaction during mRNA export.
Tritium labelled 2-trifluoroacetamidobenzenesulfonyl fluoride

Here, we report the synthesis of high specific activity tritiated 2-trifluoroacetamidobenzenesulfonyl fluoridea potent elastase inhibitor. Preparation of a ring iodinated precursor followed by palladium on CaCO3 catalyzed deiodination with deuterium and tritium gas afforded high levels of isotope incorporation in both cases.
A Note on the Local Economic Impact of Sports Expenditures

Public subsidies for sports stadiums and arenas are often justified as a means to boost the local economy. The argument relies on historical local economic impact multipliers that misrepresent the ...
Interaction styles and input/output devices

Plus que les performances d'un systeme technologique, ce sont les possibilites de communication et leurs resultats qui peuvent etre ameliores. L'auteur developpe ici des mecanismes d'entree ou de sortie des donnees qui permettraient une meilleure communication ordinateur-utilisateur.
Approaches and tools for modeling signaling pathways and calcium dynamics in neurons

Signaling pathways are cascades of intracellular biochemical reactions that are activated by transmembrane receptors, and ultimately lead to transcription in the nucleus. In neurons, both calcium permeable synaptic and ionic channels as well as G protein coupled receptors initiate activation of signaling pathway molecules that interact with electrical activity at multiple spatial and time scales. At small temporal and spatial scales, calcium modifies the properties of ionic channels, whereas at larger temporal and spatial scales, various kinases and phosphatases modify the properties of ionic channels, producing phenomena such as synaptic plasticity and homeostatic plasticity. The elongated structure of neuronal dendrites and the organization of multi-protein complexes by anchoring proteins imply that the spatial dimension must be explicit. Therefore, modeling signaling pathways in neurons utilizes algorithms for both diffusion and reactions. The small size of spines coupled with small concentrations of some molecules implies that some reactions occur stochastically. The need for stochastic simulation of many reaction and diffusion events coupled with the multiple temporal and spatial scales makes modeling of signaling pathways a difficult problem. Several different software programs have achieved different aspects of these capabilities. This review explains some of the mathematical formulas used for modeling reactions and diffusion. In addition, it briefly presents the simulators used for modeling reaction-diffusion systems in neurons, together with scientific problems addressed.
G-protein-coupled Receptor (GPCR) Kinase Phosphorylation and β-Arrestin Recruitment Regulate the Constitutive Signaling Activity of the Human Cytomegalovirus US28 GPCR

Phosphorylation of G-protein-coupled receptors (GPCRs) by GRKs and subsequent recruitment of beta-arrestins to agonist-occupied receptors serves to terminate or attenuate signaling by blocking G-proteins from further interaction with the receptors. Human cytomegalovirus encodes a GPCR termed US28 that is homologous to the human chemokine family of GPCRs but differs from the cellular receptors in that it maintains high constitutive activity in the absence of agonist. Although US28 is constitutively active, mechanisms that regulate this activity are unknown. We provide evidence that US28 is constitutively phosphorylated by GRKs in cells and that in consequence, beta-arrestin 2 is localized to the plasma membrane. Deletion of the carboxyl terminal 40 amino acids in US28 generates a receptor that is severely impaired in its ability to become phosphorylated and recruit beta-arrestin and accordingly demonstrates increased inositol phosphate signaling. This result indicates that the carboxyl terminus of US28 contains an important signaling regulatory region and mutational analysis deleting carboxyl terminal serines identified serine 323 as a critical residue within this region. In addition, overexpression of wild type GRK5 leads to hyperphosphorylation of US28 that results in a decrease of inositol phosphate accumulation. These results are consistent with the hypothesis that GRK phosphorylation and recruitment of beta-arrestin to the US28 viral GPCR attenuates signaling to the traditional Galphaq-stimulated inositol phosphate pathway. Finally, in contrast to the results with inositol phosphate signaling, we provide evidence that the US28 carboxyl-terminal phosphorylation sites and beta-arrestin-interacting domain are required for maximal activation of the p38 mitogen-activated protein kinase. Taken together, these results indicate that US28 interacts with these important regulatory proteins to control multiple aspects of signal transmission. Understanding the regulation of viral GPCRs by GRKs and beta-arrestins will provide important new insights into not only aspects of viral pathogenesis but also basic mechanisms of receptor signaling.
Supraspinal cholecystokinin may drive tonic descending facilitation mechanisms to maintain neuropathic pain in the rat.

Abstract Complete or partial spinal section at T8 has been shown to block tactile allodynia but not thermal hyperalgesia following L5/L6 spinal nerve ligation (SNL), suggesting the supraspinal integration of allodynia in neuropathic pain. In the present study, the possibility of mediation of nerve injury-associated pain through tonic activity of descending nociceptive facilitation arising from the rostroventromedial medulla (RVM) was investigated. Specifically, the actions of brainstem cholecystokinin and the possible importance of sustained afferent input from injured nerve fibers were determined using pharmacological and physiological approaches in rats with SNL. Lidocaine given bilaterally into the RVM blocked tactile allodynia and thermal hyperalgesia in SNL rats and was inactive in sham-operated rats. Bilateral injection of L365,260 (CCKB receptor antagonist) into the RVM also reversed both tactile allodynia and thermal hyperalgesia. Microinjection of CCK-8 (s) into the RVM of naive rats produced a robust tactile allodynic effect and a more modest hyperalgesia. CCK immunoreactivity was not significantly different between SNL and sham-operated rats. The anti-nociceptive effect of morphine given into the ventrolateral periaqueductal gray region (PAG) was substantially reduced by SNL. The injection of L365,260 into the RVM or of bupivacaine at the site of nerve injury restored the potency and efficacy of PAG morphine in SNL rats. These results suggest that changes in supraspinal processing are likely to contribute to the observed poor efficacy of opioids in clinical states of neuropathic pain. These data also indicate that the activation of descending nociceptive facilitatory pathways is important in the maintenance of neuropathic pain, appears to be dependent on CCK release, and may be driven from sustained afferent input from injured nerves to brainstem sites. Collectively, these data support the hypothesis that abnormal tonic activity of descending facilitation mechanisms may underlie chronic pain from peripheral nerve injury.
A Compact Physical AlGaN/GaN HFET Model

We introduce a physics-based compact model for AlGaN/GaN heterojunction field-effect transistors (HFETs) that is suitable for both RF microwave and switched-mode power supply (SMPS) applications, so that RF techniques can help determine HFET performance in SMPS applications. Such simulations can predict the on-resistance, slew rate, and breakdown voltage from the physical design of the transistor. Starting from an expression for the drain-source conduction current, charge distribution and displacement current are determined. The new model was implemented in Verilog-A and implemented in AWRDE, the design environment from Applied Wave Research. The HFET model was validated by comparison with Silvaco simulations and with data from an AlGaN/GaN HFET S-band amplifier. The new model accurately predicts device performance for dc, small-signal, and large-signal operations.
Escherichia coli RNase HI inhibits murine leukaemia virus reverse transcription in vitro and yeast retrotransposon Ty1 transposition in vivo.

Background: Reverse transcription, which converts an RNA genome into double-stranded DNA, requires both the polymerase and RNase H activities of reverse transcriptase (RT). In vitro, poorly processive RT dissociates from partially copied RNA–DNA hybrids, that are usually extended by a second RT molecule. Despite similar structures, RNase HI of Escherichia coli can degrade RNA–DNA hybrids that are resistant to RNase H of RT. E. coli RNase HI is used to determine the accessibility to and requirement for RNA–DNA hybrids in reverse transcription in vivo and in vitro. Results: In the presence of E. coli RNase HI, reverse transcription yields incomplete cDNA molecules due to degradation of RNA–DNA hybrids. Delivery of E. coli RNase HI to Ty1 particles via fusion to the capsid protein can reduce retrotransposition by more than 99%, also indicating inhibition of DNA synthesis in vivo. Conclusion: Inhibition of both reverse transcription in vitro and retrotransposition in vivo by E. coli RNase HI indicates that the poor processivity of RT exposes RNA–DNA hybrids critical for reverse transcription to degradation. Targeting a cellular RNase H to HIV may help define the site(s) of RNA–DNA hybrids that are susceptible to non-retroviral RNase H and may be useful for gene therapy to inhibit retroviral replication.
Optimal design for sustainable development of a material recovery facility in a fast-growing urban setting.

Abstract Installing material recovery facilities (MRFs) in a solid waste management system could be a feasible alternative to achieve sustainable development goals in urban areas if current household and curbside recycling cannot prove successful in the long run. This paper addresses the optimal site selection and capacity planning for a MRF in conjunction with an optimal shipping strategy of solid waste streams in a multi-district urban region. Screening of material recovery and disposal capacity alternatives can be achieved in terms of economic feasibility, technology limitation, recycling potential, and site availability. The optimization objectives include economic impacts characterized by recycling income and cost components for waste management, while the constraint set consists of mass balance, capacity limitation, recycling limitation, scale economy, conditionality, and relevant screening constraints. A case study for the City of San Antonio, Texas (USA) presents a vivid example where scenario planning demonstrates the robustness and flexibility of this modeling analysis. It proves especially useful when determining MRF ownership structure. Each scenario experiences two case settings: (1) two MRF sites are proposed for selection and (2) a single MRF site is sought. Cost analysis confirms processing fees are not the driving force in the City’s operation, but rather shipping cost. Sensitivity analysis solidifies the notion that significant public participation plays the most important role in minimizing solid waste management expenses.
Advanced fuel elements for passive pressure tube light water reactors

This paper focuses on the development of advanced fuel elements for innovative pressure tube light water reactors. Considerations and constraints that affect the design process and various possible options are discussed. The two most promising fuel designs, which can survive a loss-of-coolant accident without primary coolant replenishment, while having sufficient margins to fuel design limits, are proposed, described and evaluated. It is demonstrated that this key objective can be achieved, provided that reliable SiC cladding or coating, which can withstand operating and accident conditions without failure, can be manufactured. Recent advances in ceramic coating technologies and experimental tests of coated specimens indicate that the attainment of this goal is feasible.
A factorial study of temperament.

The theory is advanced that personality factors obtained in the first order may often represent combinations of temperament traits that occur in the experimental population. Under these circumstances an investigation of the second order represents a purification process and yields factors which represent the more basic or pervasive characteristics of the original behavior items included in the factorial study. These second-order factors can be obtained directly in the first order by a careful selection of the variables which enter into the analysis. A second-order analysis was undertaken of the nine factors inherent in three of J. P. Guilford's inventories, and four clearly interpretable second-order factors were obtained. Three of these factors were obtained directly in the first order in a new factorial study of twenty-two behavior items. Attention is drawn to the similarities between these factors and traits of temperament postulated by an independent investigator.
Reduction of sonic boom by azimuthal redistribution of overpressure.

Sonic boom reduction by azimuthal redistribution of supersonic aircraft pressure field variation
Role of the proposed serpin-enzyme complex receptor recognition site in binding and internalization of thrombin-heparin cofactor II complexes by hepatocytes.

Abstract Several serpin-enzyme complexes bind to a receptor on hepatocytes that mediates their endocytosis and lysosomal degradation. Joslin et al. (Joslin, G., Fallon, R. J., Bullock, J., Adams, S. P., and Perlmutter, D. H. (1991) J. Biol. Chem. 266, 11282-11288) proposed that a sequence near the C-terminal end of the serpin (e.g. FVFLM in α1-antitrypsin) binds to the serpin-enzyme complex receptor (SEC receptor). In experiments with synthetic peptides, they found that substitution of alanine at the fourth or fifth position in this sequence reduced the affinity of peptide binding to Hep G2 cells. To test the hypothesis that the corresponding sequence in heparin cofactor II (HCII), FLFLI (residues 456-460), mediates binding and uptake of the thrombin-HCII complex by Hep G2 cells, we constructed five recombinant HCII variants, F456A, L457A, F458A, L459A, and I460A. At 4°C, the 125I-thrombin-HCII(native) complex bound reversibly to 0.6-2.6 × 105 sites per Hep G2 cell with a Kd of 19-32 nM. Binding was inhibited by excess unlabeled thrombin-HCII(native), thrombin-antithrombin, or elastase-α1-antitrypsin, but not by free HCII or thrombin, which is consistent with the reported specificity of the SEC receptor. However, complexes of thrombin with each of the HCII variants inhibited binding as effectively as the complex with native HCII. Competitive binding experiments with various concentrations of unlabeled thrombin-HCII(native) or thrombin-HCII(I460A) indicated that these complexes bind to Hep G2 cells with equal affinity. At 37°C, complexes of 125I-thrombin with each of the five HCII variants were internalized and degraded at the same rate as the complex with native HCII. Our data suggest that the pentapeptide FLFLI in HCII is not involved in binding, internalization, and degradation of thrombin-HCII complexes by Hep G2 cells.
Modeling of elastic and inelastic scattering effects in oceanic optics

The results of model calculations of apparent optical properties for realistic marine waters with inclusion of Raman scattering and fluorescence are presented. It is shown that the underwater light spectrum can be divided, by a threshold wavelength, into two regions with different behavior of apparent optical properties, and also that inelastic effects are significant and should be considered in ocean optics measurements.
Graphical representation of prism coupling into thin films.

A natural framework for evaluating prism-coupler performance is provided by a recently developed geometrical construction in which refraction through a prism for an arbitrary angle of incidence is represented by an ellipse. The useful operating range of a prism coupler is represented by the portion of the representational ellipse that appears within a window determined by the mode propagation conditions of a thin-film–substrate system.
Observations of ionospheric ELF and VLF wave generation by excitation of the thermal cubic nonlinearity.

Extremely-low-frequency (ELF, 3--3000 Hz) and very-low-frequency (VLF, 3--30 kHz) waves generated by the excitation of the thermal cubic nonlinearity are observed for the first time at the High-Frequency Active Auroral Research Program high-frequency transmitter in Gakona, Alaska. The observed ELF and VLF field amplitudes are the strongest generated by any high frequency (HF, 3--30 MHz) heating facility using this mechanism to date. This manner of ELF and VLF generation is independent of naturally forming currents, such as the auroral electrojet current system. Time-of-arrival analysis applied to experimental observations shows that the thermal cubic ELF and VLF source region is located within the collisional $D$-region ionosphere. Observations are compared with the predictions of a theoretical HF heating model using perturbation theory. For the experiments performed, two $X$-mode HF waves were transmitted at frequencies ${\ensuremath{\omega}}_{1}$ and ${\ensuremath{\omega}}_{2}$, with $|{\ensuremath{\omega}}_{2}\ensuremath{-}2{\ensuremath{\omega}}_{1}|$ being in the ELF and VLF frequency range. In contrast with previous work, we determine that the ELF and VLF source is dominantly produced by the interaction between collision frequency oscillations at frequency ${\ensuremath{\omega}}_{2}\ensuremath{-}{\ensuremath{\omega}}_{1}$ and the polarization current density associated with the lower frequency HF wave at frequency ${\ensuremath{\omega}}_{1}$. This specific interaction has been neglected in past cubic thermal nonlinearity work, and it plays a major role in the generation of ELF and VLF waves.
An electrophysiological investigation of the effects of coreference on word repetition and synonymy

In two experiments the effects of word repetition, synonymy, and coreference on event-related brain potentials during text processing were studied. Participants read one (Experiment 1) or two sentence (Experiment 2) texts in which critical nouns were preceded by the definite (the) or indefinite (a) articles. Experiment 1 was run as a control to verify that differences in article processing in the second sentences of Experiment 2 would not contaminate the ERPs to critical noun items. They did not. In Experiment 2, an initial sentence was used to set up a context and contained either a first presentation or synonym of the critical word from the second sentence. N400 (but not Late Positive Component; LPC) priming effects were found for repetitions and synonyms (larger for repetitions) in second sentences. This extends observations of priming in word lists and single sentences to two-sentence texts. There was also a greater left anterior negativity or “LAN” for coreferential critical nouns (those following the article “The”) compared to non-coreferential critical nouns (those following the article “A”) suggesting that ERPs are sensitive to working memory processes engaged during referential assignment. In response to the articles themselves, there was a greater N400-700 elicited by the article “A” vs. “The.” Finally, there was a greater N400-like negativity to the final words of non-coreferential sentences implying that the meanings of these sentences were difficult to integrate with the discourse level representation established by the prior sentence.