cssi/SciSciGPT-SciSciNet huggingface dataset:
Purification and Properties of Dextransucrase from Streptococcus mutans

Abstract The dextransucrase (EC 2.4.1.5) activity from cell-free culture supernatants of Streptococcus mutans strain 6715 has been purified approximately 1,500-fold by ammonium sulfate precipitation, hydroxylapatite chromatography, and isoelectric focusing. The enzyme was eluted as a single peak of activity from hydroxylapatite, and isoelectric focusing of the resulting preparation gave a single band of dextransucrase activity which focused at a pH of 4.0. The final enzyme preparation contained two distinct, enzymatically active proteins as judged by assay in situ after polyacrylamide gel electrophoresis. One of the proteins represented 90% of the total dextransucrase activity and 53% of the total protein. The molecular weight of the enzyme was estimated by gel filtration to be 94,000. The temperature optimum of the enzyme was broad (34 to 42 C) and its pH range was rather narrow, with optimal activity at pH 5.5. The Km for sucrose was 3 mM, and fructose competitively inhibited the enzyme reaction with a Ki of 27 mM.
The First Quarter Century of the GASB (1984–2009): A Perspective on Standard Setting (Part One)

The Governmental Accounting Standards Board (hereafter GASB or Board) was established in April 1984 as the authoritative accounting standard-setting body for United States state and local governmental entities. There are over 87,000 state and local entities in the country, and for the most part these entities are required to comply with the generally accepted accounting principles established by the GASB; hence, the work of the GASB is significant. On 30 June 2009, the GASB completed its twenty-fifth year of standard setting. Because of the Board's influence and the importance of its mission, an increased understanding of the GASB and its accomplishments during its first 25 years of existence is important. This is the first of two papers which together provide a complete sequential treatment of the GASB's operational history through the end of its first quarter century. This first paper begins with an historical perspective about municipal accounting issues from colonial times to 1934. The origin of professional self-determining standards is the feature of the next section, identifying standard-setting bodies that contributed to municipal accounting from 1934 to 1984. The early activities of the Board are then reviewed. Two appendices are provided to detail the composition of the Board during its first quarter century, along with biographical information about the early Board members and later Chair and Vice Chair personnel. This segment concludes with a review of the relationship of other governmental standard setting bodies at the federal level and the international level.
Transport and sedimentation of particles in a fluid flow

A simple two-dimensional random walk model is developed for the motion of a particle in a fluid flow. Some earlier results for the persistent injection of particles into the flow are extended, and the distribution of the maximum number of particles in suspension over the period (0,t) is derived.
A New Resource: The Waste-to-Energy Research and Technology Council

Despite the fact that there are over one hundred Waste-to-Energy (WTE) facilities around the country serving tens of millions of people, there are no industrial or government research centers dedicated to solving problems and improving the WTE technology. In recognition of this fact, the Waste-to-Energy Research and Technology (WTERT) Council was formed in May 2002. Its mission is to link academic researchers and professionals concerned with integrated waste management and energy recovery from wastes and promote R&D that will advance resource recovery by combustion or gasification. This paper reports on the activities of WTERT in its first year and the research directions that have been identified and initiated.Copyright © 2003 by ASME
Phosphorylation heterogeneity of tryptic phosphopeptides of chicken riboflavin-binding protein.

Summary The tryptic phosphopeptide of hen egg white riboflavin-binding protein has been found to exist as a mixture of peptides which differ only with respect to the number of covalently bound phosphoryl groups. Anion-exchange chromatography was used to separate homologues of the tryptic phosphopeptide of egg white riboflavin-binding protein. Four peptide peaks were obtained and analyzed using plasma desorption mass spectrometry. Molecular ions obtained agree closely with calculated molecular weight values for phosphopeptides with 8, 7 and 5 phosphoryl groups. Amino acid analyses showed that the octa- and hepta-phosphorylated peptides were pure and had the same amino acid compositions.
Electrical and photoelectrochemical properties of WO3/Si tandem photoelectrodes

Tungsten trioxide (WO3) has been investigated as a photoanode for water oxidation reactions in acidic aqueous conditions. Though WO3 is not capable of performing unassisted solar-driven water splitting, WO3 can in principle be coupled with a low band gap semiconductor, such as Si, to produce a stand-alone, tandem photocathode/photoanode p-Si/n-WO3 system for solar fuels production. Junctions between Si and WO3, with and without intervening ohmic contacts, were therefore prepared and investigated in detail. Thin films of n-WO3 that were prepared directly on p-Si and n-Si substrates exhibited an onset of photocurrent at a potential consistent with expectations based on the band-edge alignment of these two materials predicted by Andersen theory. However, n-WO3 films deposited on Si substrates exhibited much lower anodic photocurrent densities (∼0.02 mA cm–2 at 1.0 V vs SCE) than identically prepared n-WO3 films that were deposited on fluorine-doped tin oxide (FTO) substrates (0.45 mA cm–2 at 1.0 V vs SCE). D...
PCM/FM Telemetry Signal Analysis and Bandwidth Effects

The spectra of FM signals corresponding to various pulse shapes (of relevance in PCM work) are determined. The corresponding demodulated output pulse shapes in a limiter-discriminator receiving system have also been obtained. Both analytical and graphical results are given.
Alcohol exposure in utero and breast cancer risk later in life

Since the pioneering work of Hiatt and Bawol (1984), there has amassed a considerable amount of evidence that moderate-to-heavy alcohol consumption increases risk of breast cancer in women (Willett et al. , 1987; Longnecker, 1999). A plausible mechanism is by alcohol's effects on circulating hormone levels. Alcohol administration has been reported to increase circulating oestradiol levels in pre-menopausal women (Reichman et al. , 1993); the evidence is mixed in post-menopausal women (Purohit, 1998). In a cross-sectional study of pre-menopausal women, Muti et al. (1998) determined an association between reported alcohol consumption and serum oestradiol levels during the luteal phase of the menstrual cycle, and found an 18% elevation in drinkers, consuming an average 1 drink per day, compared to abstainers. It is not clear how alcohol affects circulating oestradiol levels. Alcohol has been reported to increase aromatase activity; i.e., the …
Original paper: Data modeling to facilitate internal traceability at a grain elevator

Data management in food supply chains to facilitate product traceability has gained importance in recent years. This paper presents a relational database model to facilitate internal traceability at a grain elevator, which is one of the first nodes in a food supply chain. This approach for modeling traceability information in bulk food supply chains has not been studied in past. At an elevator, grain lots (inbound deliveries) are blended to meet buyer specifications, and individual lot identity is not maintained. As a result, an outbound shipment to a customer likely contains grain from many different sources. In a food safety related emergency, tracing the source of a problem or tracking other affected shipments would be nearly impossible. An efficient internal data management system could mitigate these problems by recording all grain lot transformations/activities, including movement, aggregation, segregation, and destruction as well as supplier and customer information. In this paper, a relational database management system is proposed that stores all necessary information, including product and quality information, related to the grain lots in order to enable product traceability. The system can be queried to retrieve information related to incoming, internal and outgoing lots and to retrieve information that connects the individual incoming grain lots to an outgoing shipment. Furthermore, this system can be used both to trace back to the source of a given lot and to track information about previously shipped lots forward. In addition to traceability application, the information stored in this database provides a comprehensive dataset for many applications including mass flow optimization, resource optimization and improved operational efficiency of the grain elevator.
National study of US emergency department visits for acute allergic reactions, 1993 to 2004.

Background The clinical epidemiology of acute allergic reactions in the emergency department (ED) is uncertain. Objectives To characterize ED visits for acute allergic reactions and to evaluate national trends in ED management. Methods The National Hospital Ambulatory Medical Care Survey was used to identify a nationally representative sample of ED visits between 1993 and 2004. Cases with a diagnosis of acute allergic reaction were identified by International Classification of Diseases, Ninth Revision (ICD-9) codes (9950, 9951, 9952, 9953, 9956). Results A total of 12.4 million allergy-related ED visits occurred from 1993 to 2004, representing 1.0% (95% confidence interval, 0.93%-1.10%) of all ED visits or 1.03 million ED visits per year. The number of allergy-related ED visits remained relatively stable, averaging 3.8 per 1,000 US population per year (95% confidence interval, 3.4–4.1; P for trend=.39). Although 63% of all visits were coded as urgent, only 4% required hospitalization. Anaphylaxis coding was rare (1%). ED staff prescribed medications in 87% of visits, especially histamine 1 blockers (62%; P for trend=.29). Increases were noted from 1993 to 2004 for corticosteroids (22% to 50%; P 2 blockers (7% to 18%; P P = .008). Epinephrine use was infrequent and declining (19% to 7%; P = .04). Conclusion Between 1993 and 2004, significant variability has occurred in ED management of acute allergic reactions.
Stabilization of phosphofructokinase with sugars during freeze-drying: characterization of enhanced protection in the presence of divalent cations

Phosphofructokinase purified from rabbit skeletal muscle is fully inactivated after freeze-drying and dissolution. The addition of trehalose or maltose to the enzyme solution prior to freeze-drying results in a recovery of up to 80% of the original activity. Slightly less stabilization is imparted by sucrose, whereas glucose and galactose at concentrations up to 500 mM are relatively ineffective at protecting phosphofructokinase. Addition of ionic zinc to enzyme-sugar mixtures prior to freeze-drying greatly enhances the stabilization imparted by the above sugars. This effect is not simply due to the summation of the individual protective capacities of zinc and the sugar. Zinc alone affords no protection, but a high degree of stabilization is achieved when zinc is added to a sugar solution, even when the sugar is at a concentration at which, by itself, it is totally ineffective. In the presence of a constant sugar concentration (100 mM), freeze-dry stabilization of phosphofructokinase is increased as the concentration of zinc is increased. When the zinc concentration is held constant (0.9 mM) and the sugar concentration varied, the maximum stabilization is noted with less than 200 mM sugar. At higher solute concentrations the degree of enhancement decreases such that with 500 mM sugar the addition of zinc results in only a slight increase in protection. Several other organic solutes (proline, 4-hydroxyproline, glycine, trimethylamine N-oxide, glycerol and myo-inositol) that afford cryoprotection to phosphofructokinase, an effect enhanced by the addition of zinc, do not stabilize the enzyme during freeze-drying, even if zinc is present. The addition of ionic copper, cadmium, nickel, cobalt, calcium and manganese to trehalose-phosphofructokinase solutions prior to freeze-drying also increases the percentage of activity recovered after dissolution. Magnesium is ineffective in this respect.
Interaction between radiation and drug damage in mammalian cells. II. The effect of actinomycin‐D on the repair of sublethal radiation damage in plateau phase cells

The effect of actinomycin-D (AMD) on radiation damage repair was studied in plateau phase V79 Chinese hamster cells. Sublethal radiation damage repair, as demonstrated by survival fluctuations following two x-ray exposures separated by time was observed in our plateau phase cells. Plateau phase cells exposed to 0.01 to 0.04 ..mu..g/ml AMD (a nontoxic regimen to 8 hours) between x-ray exposures were less able to repair sublethal damage. If plateau phase cells were plated at low dilutions into fresh medium (conditions for resuming exponential growth) immediately after the first x-ray dose, and exposed to 0.01 to 0.04 ..mu..g/ml AMD until the second dose, inhibition of sublethal damage repair and additional cell killing were observed particularly at 0.04 ..mu..g/ml AMD. It is suggested that radiation-drug damage interactions should be studied in plateau phase cells and in cells resuming exponential growth after plateau phase (possibly analogous to ''recruitment''), as well as in exponential phase cultures.
Space perception in virtual environments: Displacement from the center of projection causes less distortion than predicted by cue-based models

Virtual reality systems commonly include both monocular and binocular depth cues, which have the potential to provide viewers with a realistic impression of spatial properties of the virtual environment. However, when multiple viewers share the same display, only one viewer typically receives the projectively correct images. All other viewers experience the same images despite displacement from the center of projection (CoP). Three experiments evaluated perceptual distortions caused by displacement from the CoP and compared those percepts to predictions of models based on monocular and binocular viewing geometry. Leftward and rightward displacement from the CoP caused virtual angles on the ground plane to be judged as larger and smaller, respectively, compared to judgments from the CoP. Backward and forward displacement caused rectangles on the ground plane to be judged as larger and smaller in depth, respectively, compared to judgments from the CoP. Judgment biases were in the same direction as cue-based model predictions but of smaller magnitude. Displacement from the CoP had asymmetric effects on perceptual judgments, unlike model predictions. Perceptual distortion occurred with monocular cues alone but was exaggerated when binocular cues were added. The results are grounded in terms of practical implications for multiuser virtual environments.
A high-speed optical multi-drop bus for computer interconnections

Buses have historically provided a flexible communications structure in computer systems. However, signal integrity constraints of high-speed electronics have made multi-drop electrical buses infeasible. Instead, we propose an optical data bus for computer interconnections. It has two sets of optical waveguides, one as a fan-out and the other as a fan-in, that are used to interconnect different modules attached to the bus. A master module transmits optical signals which are received by all the slave modules attached to the bus. Each slave module in turn sends data back on the bus to the master module. Arrays of lasers, photodetectors, waveguides, microlenses, beamsplitters, and Tx/Rx integrated circuits are used to realize the optical data bus. With 1 mW of laser power, we are able to interconnect eight different modules at 10 Gb/s per channel. An aggregate bandwidth of over 25 GB/s is achievable with 10-bit wide signaling paths.
A functional γ gene formed from known γ-gene segments is not necessary for antigen-specific responses of murine cytotoxic T lymphocytes

Structural similarities between surface immunoglobulins (s Ig) on B cells and antigen-specific receptors on T cells suggest that a T cell, like a B cell, should express only two immunoglobulin-like genes, one for each subunit of the disulphide-linked, heterodimeric, antigen-specific (alpha beta) T-cell receptor. However, cytotoxic T lymphocytes (Tc cells) and immature thymocytes also contain RNA transcripts of a third immunoglobulin-like gene, called gamma (refs 1-4). A polypeptide corresponding to the gamma gene has not yet been identified and the function of this gene remains an enigma. Judging from its nucleotide sequence, the rearranged gamma gene is expected to encode an integral membrane polypeptide chain, and gamma complementary DNAs from two cloned Tc cell lines have previously been found to have different sequences around the V-J (variable region-joining region) junction, suggesting that, in these cells, the gamma-gene product is a clonally diverse surface structure that may form part of an as yet unidentified, antigen-specific receptor. To analyse further the extent of diversity of the gamma-gene product, we have determined the partial sequences of 11 gamma cDNA clones from three other cloned Tc cell lines, and report here that the sequences are indeed clonally diverse, but in all instances they are out-of-phase in the region of the V-J junction. This finding and the pattern of gamma-gene rearrangements in these cell lines indicate that a polypeptide product of the previously reported gamma gene, V2J2-C2, is not expressed in them and is, therefore, not necessary for the antigen-specific cytotoxic and proliferative responses of these mature T cells.
Long-term follow-up of patients undergoing closed transventricular mitral commissurotomy: A useful surrogate for percutaneous balloon mitral valvuloplasty?

Abstract Objective . The aim of this study was to determine the long-term outcome and multivarviate predictors of late events in patients who underwent transventricular mitral commissurotomy at the Mayo Clinic in the early 1960s. Background . Percutaneous balloon mitral valvuloplasty is an important new procedure for which long-term follow-up data are not yet available. However, such data do exist for patients who have undergone transventricular mitral commissurotomy, a similar but older and more invasive procedure. Methods . Follow-up data (mean duration 13.9 years) for 207 women and 60 men who underwent transventricular mitral commissurotomy were obtained from medical records, referring physicians, questionnaires and telephone interviews. Survival and survival free of repeat commissurotomy or mitral valve surgery were estimated with the Kaplan-Meier method. Cox proportional hazards model was used to determine predictors of survival and repeat mitral valve surgery. Results , Postoperatively, 92% of patients had symptomatic improvement, which was sustained for at least 3 to 4 years in 78%. At 10 15 and 20 years postoperatively, 79%, 67% and 55%, respectively, of patients were alive and 57%, 36% and 24%, respectively, were alive and free of repeat mitral valve surgery. At 10 years, 90% of all patients were free of transient or fixed cerebrovascular events. In multivariate analyses, atrial fibrillation, age and male gender were independently associated with death, whereas mitral valve calcification, cardiomegaly and mitral regurgitation independently predicted repeat mitral valve surgery. Conclusions . Long-term results after transventricular mitral commissurotomy are excellent in selected patients with symptomatic mitral stenosis. Because of similarities in patient selection and mechanisms of mitral valve dilation, similar favorable loag-term outcomes may be expected after percutaneous balloon mitral valvuloplasty.
Variations in the onset of bottom-water intrusions over the entrance sill of a fjord

Puget Sound is a fjord-like estuary and bottom-water intrusions are major circulation features which play a dominant role in the replacement of water below still depth. New observations on the inside and outside of the entrance sill show that, while intrusions occur during neap tides as previously thought, the onset of the intrusions is a results off fluctuations in the horizontal density gradient caused by salinity variations across the sill. Salinity changes outside the sill in the Strait of Juan de Fuca estuary appear to be the result of storms on the Pacific Coast causing reversals of surface flow and variations in deep flow more than 135 km from the coast. Previous observations have shown deep salinity variations midway along the straight, but these are the first to show this effect can penetrate the full length of the Strait causing near-bottom salinity variations of sufficient magnitude to influence flow into Puget Sound. This influence probably occurs from the onset of storms in autumn through subsidence in spring, although occasional large storms occur in summer. Although Puget Sound is more characteristic of a fjord, the simple model calculations here suggest similar processes may occur in lower-layer flow at the mouth of coastal plain estuaries.
Phasic muscle activity in sleep and clinical features of Parkinson disease

Polysomnographic studies across a broad spectrum of alpha-synucleinopathies (including idiopathic Parkinson disease [PD], dementia with Lewy bodies [DLB], and idiopathic rapid eye movement [REM] sleep behavior disorder [RBD]) point to absence of REM sleep atonia as a common feature in these conditions.1–5 A key aspect of these observations is that RBD typically precedes the explicit diagnosis of PD or DLB, often by periods of several decades,5–7 and may represent an exceptionally early marker of synucleinopathic degeneration. Perhaps less well established is whether signs of RBD may also be prognostic of disease features once a diagnosis of Parkinsonism has been established. Disease progression in PD remains an incompletely understood phenomenon, although certain subtypes (eg, tremorous) usually are considered to herald a slower disease course than others (eg, bradykinetic/rigid).8,9 Additionally, early stage PD typically manifests asymmetrically, whereas later stage disease typically involves both body sides.8,10 In this cross-sectional study, we sought to evaluate whether, within a group of idiopathic PD patients, specific neurophysiological markers derived from overnight polysomnography (PSG) were associated with clinical indices typically associated with more advanced disease or more progressive disease course. Observations of RBD in parkinsonism have typically, but not exclusively, been derived from clinicians' judgments, based on history and occasionally supplemented by standardized questionnaires. However, measurements of phasic muscle activity recorded from surface electromyographic (EMG) electrodes have indicated large and robust effects in distinguishing the sleep of PD and idiopathic RBD patients who were not yet parkinsonian,11–15 with significantly higher rates of phasic discharges noted relative to controls. Very recently, Iranzo et al16 have shown that elevated muscle activity in sleep becomes worse in idiopathic RBD patients over a mean interval of 5 years in the absence of overt parkinsonism. In this study, we investigated the extent to which such quantified activity may be related to clinical features of PD, including symmetric (SYM) versus predominantly asymmetric (ASYM) involvement, and tremor-predominant versus akinetic-rigid PD phenotype. We hypothesized that (1) patients with bilateral involvement would demonstrate higher rates of phasic muscle activity in sleep and (2) akinetic-rigid patients would exhibit greater motor activation in sleep relative to tremor-predominant patients.
Immunochemistry of the glycopeptide derived from avian riboflavin-binding protein

Abstract Immunization of rabbits with a purified glycopeptide from a pronase digest of avian riboflavin-binding protein by a modified method of Maugh (1977) resulted in the production of carbohydrate-specific antibody. A sensitive radioimmunoassay was developed to detect the low levels of antibodies, and the concentrated IgG fraction was used for immunochemical analyses. Chemical modification of the terminal sugars and hapten inhibition of the precipitin reaction between monospecific antibodies and the glycoprotein demonstrated that s-linked galactosyl residues were the immunodominant determinants of the glycopeptide. Radioimmunoassay indicated that the glycopeptide. although a structural component of the riboflavin-binding protein, did not contribute to the major antigenic determinants of the native protein.
Isolation of a new electron transport component with nicotinamide adenine dinucleotide phosphate-like activity

Abstract The enzyme system in Mycobacterium phlei that is responsible for the endogenous reduction of 2,6-dichlorophenol indophenol (2,6-DPIP) (1) has been fractionated into two components (2). One of these is a glucose 6-phosphate dehydrogenase and the second a reduced coenzyme-2,6-DPIP reductase. The crude cell-free juice (3) contains the necessary coenzyme and substrate concentrations of glucose 6-P. The only added requirement for activation of the system is the addition of 2,6-DPIP as the final electron acceptor. The nature of the components of the enzyme system suggested the addition of NADP. The level of enzyme activity obtained with added NADP was less than that observed following the addition of a boiled juice extract prepared from the crude cell-free juice. The extract was found to contain essentially no effective concentration of NADP as measured by a glucose 6-P dehydrogenase procedure. In addition no NAD was found using lactic dehydrogenase as the assay enzyme. These observations suggested that the natural coenzyme required by the enzyme system is not NADP nor NAD. In this communication a procedure for the isolation of a new electron transport component with NADP-like activity is described.
Thermolysin: a zinc metalloenzyme.

Abstract Metal analyses and inhibitor studies have shown that thermolysin, a neutral protease from B. thermoproteolyticus , is a zinc metalloenzyme. The relevance of this finding to the active site characteristics of other bacterial neutral proteases and to those of alkaline proteases is considered.
Radiation View Factors for a Toroid: Comparison of Eckert’s Technique and Direct Computation

Eckert shadow technique for radiation view factors applied to toroid inside shadow hemisphere
Catalytic enantioselective cyclopropanation of olefins using N-salicylidene-4-amino[2.2]paracyclophane as an asymmetric ligand

Abstract The chiral ligand (±)-N-salicylidene-4-amino[2.2]paracyclophane (1) was synthesized and resolved. Resolved 1 was complexed to copper(II) for use as an asymmetric catalyst for the cyclopropanation of selected styrenes and stilbenes by diazoesters. Conversions of styrenes to cyclopropanes were high, typically >90% but were less than 40% for the stilbenes. Enantioselectivity was observed for the cyclopropanation of all substrates used, ranging from 8% ee for 1,1-diphenylethylene with t-butyldiazoacetate to 41% for styrene with t-butyldiazoacetate. The origin of the differences in reactivity and enantioselectivity for this catalyst system with the different substrate/diazoester combinations is discussed with regard to a steric model.
An improved proximal tephrochronology for Redoubt Volcano, Alaska

Abstract Sediment cores from lakes in volcanically active regions can be used to reconstruct the frequency of tephra-fall events. We studied sediment cores from two lakes within 25 km of the summit of Redoubt Volcano, western Cook Inlet, to develop a robust age model for the Holocene tephrochronology, and to assess the extent to which the tephrostratigraphies were correlative between the two nearby lakes. Visually distinct tephra layers were correlated among cores from Bear and Cub lakes, located within 17 km of each other, to construct a composite age model, which incorporates two Pu-activity profiles and 27 radiocarbon ages, and extends the record back to 11,540 cal a BP. The age model was used to interpolate the ages and quantify the uncertainties of ages for all tephras at least 1 mm thick. Between − 55 and 3850 a BP, 31 tephras were deposited in Bear Lake and 41 tephras in Cub Lake. Bear Lake contains an additional 38 tephras deposited between 11,540 and 3850 a BP. During the period of overlap, (− 55 to 3850 a BP), 24 tephras are of significantly different ages, including nine from Bear Lake and 17 from Cub Lake. The presence of these unique tephras indicates that ejecta plumes erupted from Redoubt Volcano can be highly directional, and that sediment cores from more than one lake are needed for a comprehensive reconstruction of tephra-fall events. Unlike distal lakes in south Alaska, where geomorphic and limnological factors dominate the quality of the tephrostratigraphic record, the variability in tephra-fall trajectory near a Redoubt Volcano appears to be a major control on the number of tephras contained in the sediment of proximal lakes.
Customer Relationship Management considerations and Electronic Toll Collection as sustainable technology

Through the increase of technology and the implementation of Electronic Toll Collection (ETC), roads, bridges and tunnels will become more safe and convenient and can deliver socially responsible and sustainable technologies, if properly managed and encouraged. Traffic control and faster commutes will benefit motorists and enhance customer-support systems. The major purpose of this research was to investigate how ETC-based technology can control traffic and improve the safety and congestion at toll plazas and enhance Customer Relationship Management (CRM). Through the testing of hypothesis and exploratory analyses, a number of factor-based constructs, efficiency issues, personal information issues, personal internet use, problem issues, demographic maturity, clear boundaries and work-related internet use were tested. Unfortunately, it was found that management of such technology has much to do to convince potential and existing customers that there are documented socially responsible and sustainable value-added associated with using the technology.
A Dual Mechanism for Regulating cAMP Levels in Escherichia coli

In Escherichia coli, inorganic orthophosphate regulates cAMP levels by acting at two separate loci. First, adenylyl cyclase activity measured in permeabilized cells of E. coli is substantially stimulated by physiological concentrations of inorganic phosphate. This stimulation does not require the presence of cAMP phosphodiesterase activity. Second, measurements of cAMP phosphodiesterase activity in permeabilized cells show a dose-dependent inhibition of that activity by inorganic orthophosphate. A model is proposed in which inorganic orthophosphate serves as a multifaceted regulator of cAMP levels by both stimulating synthesis and inhibiting degradation of the nucleotide.
Solution route synthesis of InSb, Cu6Sn5 and Cu2Sb electrodes for lithium batteries

Abstract A solution method was used to prepare InSb, Cu 6 Sn 5 and Cu 2 Sb intermetallic compounds that are of interest as negative electrode materials for lithium batteries. The compounds were synthesized by the reduction of dissolved transition metal- and metalloid salts with fine Zn powder. Heterogeneous redox reactions at the surface of the Zn particles resulted in fern-like dendritic structures with high surface areas. Powder X-ray diffraction and lattice imaging by transmission electron microscopy showed that the intermetallic products were highly crystalline with preferred crystallographic orientations. Mild heat-treatment of the products under argon improved their phase purity. Electrodes prepared by this method exhibited a large irreversible capacity loss on the first charge/discharge cycle. Cu 2 Sb electrodes showed the greatest cycling stability; after the initial cycle, they delivered more than 230 mAh g −1 when cycled between 1.2 and 0.0 V versus metallic lithium, consistent with previously reported data for ball-milled Cu 2 Sb electrodes.
Fetal mesencephalic grafts decrease the rate of dopamine uptake in the non-lesioned striatum of unilaterally 6-OHDA lesioned rats : an in vivo voltammetric study

Abstract In the present study the influence of intraventricular fetal mesencephalic grafts on the elimination rate of extracellular dopamine (DA) in the non-lesioned striatum of previously unilaterally 6-hydroxydopamine (6-OHDA) lesioned rats was investigated. The elimination of DA was measured after electrical stimulation of the medial forebrain bundle in vivo before and after treatment with the high affinity uptake inhibitor GBR 12909 (20 mg/kg i.p.) using fast cyclic voltammetry (FCV). Rotational behavior induced by amphetamine (AMPH, 2 mg/kg i.p.) and tyrosine hydroxylase (TH) immunohistochemistry were used to prove the functional recovery and the ingrowth of the graft, respectively. After grafting, the number of rotations was decreased and TH-positive cells and fibers were found in the grafted striatum. Voltammetric measurements with the aid of a kinetic model revealed a smaller rate constant for the in vivo elimination of extracellular DA in the non-lesioned striatum of grafted rats compared to that of non-grafted controls. This effect was abolished after treatment with GBR 12909. Our results will be discussed in relation to the method used and according to recent investigations of the specific [3H]DA uptake into striatal synaptosomes in vitro. Based on these data we conclude that grafts, placed to the lesioned striatum, reduce the DA uptake rate in the non-lesioned striatum due to the reduction of the number of functional DA transporters
Dynactin Phosphorylation Is Modulated in Response to Cellular Effectors

Reversible protein phosphorylation has been implicated in the regulation of organelle transport by cytoplasmic dynein. Motor function may be modulated directly by the phosphorylation of dynein or through the phosphorylation of an accessory factor. Dynactin binds to cytoplasmic dynein and is a required activator for dynein-driven vesicular motility. In metabolic labeling studies we have determined that the p150Glued subunit of dynactin is a phosphoprotein. Treatment of Rat2 cells with okadaic acid or with activators of protein kinase A or protein kinase C caused a marked increase in the incorporation of 32P into p150Glued; the increased phosphorylation correlated with activated vesicular transport. Phosphoamino-acid analysis of p150Glued isolated from cells treated with okadaic acid or with activators of either protein kinase A or protein kinase C indicated exclusive labeling of phosphoserine. These results suggest that the phosphorylation of dynactin may serve to regulate intracellular transport catalyzed by cytoplasmic dynein.
Charcoal in northcentral Alaskan lake sediments: relationships to fire and late-Quaternary vegetation history

Abstract The charcoal content of surface and late-Quaternary lake sediments in boreal forests of northcentral Alaska was investigated using an image-analysis procedure that tallied and measured the area of charcoal particles in size classes from c. 10 4 to 10 7 μm 2 . Modern sediments were from mud-water interfaces of 29 lakes within watersheds assigned to 3 categories (unburned, partially burned, and extensively burned) based on extent of the watersheds burned in fires during 1986 and 1990. Lakes in extensively burned drainages generally contained more charcoal than did lakes in partially burned or unburned drainages, but charcoal content of sediments varied greatly within categories. Charcoal accumulation rates in a sediment core from Sithylemenkat Lake ranged between c. 1000 and 5000 μm 2 cm −2 yr −1 over the past 14,000 yr. Lowest rates occurred between c. 7000 and 5000 yr BP, after the establishment of boreal forest and during a period of abundant alder shrubs. In general, the great variability in particle sizes encountered in the modern and fossil samples from Alaskan boreal forests and the large number of particles needed to characterize trends in individual size classes suggest that an automated measurement approach, such as image analysis, is needed for quantifying sediment charcoal.
Profiles of Medicinal Cannabis Patients Attending Compassion Centers in Rhode Island

AbstractLittle is understood regarding medicinal marijuana dispensary users. We sought to characterize socio-demographics and reasons for medicinal marijuana use among medical cannabis dispensary patients in Rhode Island. Participants (n=200) were recruited from one of two Compassion Centers in Rhode Island and asked to participate in a short survey, which included assessment of pain interference using the Brief Pain Inventory (BPI). The majority of participants were male (73%), Caucasian (80%), college educated (68%), and had health insurance (89%). The most common reason for medicinal marijuana use was determined to be chronic pain management. Participants were more likely to have BPI pain interference scores of > 5 if they were older (OR: 1.36, 95% CI: 1.04–1.78) or reported using cannabis as a substitute for prescription medications (OR: 2.47, 95% CI: 1.23–4.95), and were less likely to have interference scores of >5 if they had higher income levels (OR: 0.53, 95% CI: 0.40–0.70) or reported having eve...
Catalyst degradation in high temperature methanation

The activity of nickel and nickel bimetallic methanation catalysts was investigated under conditions representative of an industrial high temperature methanator. All catalysts were observed to suffer significant losses in activity above 723 K as a result of sintering and carbon deposition. At temperatures exceeding 723 K Ni/Al2O3 and Ni/NiAl2O4 catalysts are the most active while Ni/NiAl2O4 and Ni-MoO3/Al2O3 catalysts are the most thermally stable, even in comparison with commercially available catalysts. The contributions of sintering and carbon deposition to catalyst degradation in the presence and absence of reactant steam are presented and discussed. In long term tests of Ni/Al2O3 at 773 K, accumulated carbon resulted in plugging of the reactor and catastrophic failure after only 17 hours. Analysis by transmission electron microscopy of samples run at high temperature showed the presence of carbon filaments terminated by nickel crystallites.
Image reconstruction on virtual PI-lines using filtered-backprojection in circular cone-beam CT

Recently, a 3D filtered-backprojection (FBP)-based algorithm for image reconstruction on PI-line segments in a helical cone-beam CT scan has been developed (Zou and Pan, 2004). In the present work, we derive new reconstruction algorithms for circular cone-beam scans based upon this algorithm and a concept of virtual PI-line. We prove that, in the case of conventional full- and short-scan, the newly derived algorithms are mathematically identical to existing algorithms. More importantly, in the case of reduced-scans in which the scanning angle range is less than that in a short-scan, the new algorithms can yield exact region of interest (ROI) reconstruction in mid-plane and approximate ROI reconstruction in off-mid-planes. We have performed a preliminary numerical study that verifies our theoretical assertions.
Who Should Be Doing Laparoscopic Bariatric Surgery

Background: The training and credentialing of surgeons for laparoscopic bariatric surgery is controversial. We sought to determine if there is an association between surgeons' practice and choice of open or laparoscopic bariatric surgery. Methods: Members of the ASBS were surveyed via email. Associations were tested with Cochran-Mantel-Haenszel or Pearson's chi-square. Results: 104/472 members responded; 65% were in private practice; 47% did 1-5 operations/week, 48% offered open procedures only, and 76% undertook gastric bypass. Respondents believe that laparoscopic procedures: should mimic open ones (77%), are safe (63%), should be evaluated by clinical trials (48%), and that expertise in bariatric surgery is more important than laparoscopic experience. 75% believe that courses and preceptorships are important. Regarding laparoscopic operations, surgeons doing only open procedures believe that: 1) the ASBS should be the main credentialing body; 2) surgeons should do >25 open before laparoscopic ones; and 3) clinical trials are needed (P<0.02, all). Surgeons with laparoscopic training or practices believe that laparoscopic surgery is safe and effective (P<0.002). Both laparoscopic and open surgeons believe bariatric surgeons should be the only surgeons doing laparoscopic bariatric procedures (P<0.008). Conclusions:There is consensus that laparoscopic bariatric surgery should be undertaken only by surgeons with strong interest in bariatric surgery. Laparoscopic bariatric surgeons should incorporate lessons learned from open surgery. Both laparoscopic and open bariatric surgeons should seek added expertise via courses and preceptorships.The skepticism of surgeons with 'open' practices could be addressed by clinical trials. The ASBS should maintain its leadership position and foster emerging technologies.
Lipid specificity and location of the sterol carrier protein-2 fatty acid-binding site: A fluorescence displacement and energy transfer study

Although it was recently recognized that sterol carrier protein-2 (SCP-2) interacts with fatty acids, little is known regarding the specificity of SCP-2 for long-chain fatty acids or branched-chain fatty-acid-like molecules. Likewise the location of the fatty-acid binding site within SCP-2 is unresolved. A fluorescent cis-parinaric acid displacement assay was used to show that SCP-2 optimally interacted with 14–22 carbon chain lipidic molecules: polyunsaturated fatty acids > monounsaturated, saturated > branched-chain isoprenoids > branched-chain phytol-derived fatty acids. In contrast, the other major fatty-acid binding protein in liver, fatty-acid binding protein (L-FABP), displayed a much narrower carbon chain preference in general: polyunsaturated fatty acids > branched-chain phytol-derived fatty acids > 14- and 16-carbon saturated > branched-chain isoprenoids. However, both SCP-2 and l-FABP displayed a very similar unsaturated fatty-acid specificity profile. The presence and location of the SCP-2 lipid binding site were investigated by fluorescence energy transfer. The distance between the SCP-2 Trp50 and bound cis-parinaric acid was determined to be 40 A. Thus, the SCP-2 fatty-acid binding site appeared to be located on the opposite side of the SCP-2 Trp50. These findings not only contribute to our understanding of the SCP-2 ligand binding site but also provide evidence suggesting a potential role for SCP-2 and/or L-FABP in metabolism of branched-chain fatty acids and isoprenoids.
City Logistics: Freight Distribution Management with Time-Dependent Travel Times and Disruptive Events

This paper addresses freight management in large, congested urban settings. Congestion creates a substantial variation in travel time (speeds) during morning peak and evening peak periods. Besides ...
Rotating rod renewable microcolumns for automated, solid-phase DNA hybridization studies.

The development of a new temperature-controlled renewable microcolumn flow cell for solid-phase nucleic acid hybridization in an automated sequential injection system is described. The flow cell included a stepper motor-driven rotating rod with the working end cut to a 45° angle. In one position, the end of the rod prevented passage of microbeads while allowing fluid flow; rotation of the rod by 180° releases the beads. This system was used to rapidly test many hybridization and elution protocols to examine the temperature and solution conditions required for sequence-specific nucleic acid hybridization. Target nucleic acids labeled with a near-infrared fluorescent dye were detected immediately postcolumn during all column perfusion and elution steps using a flow-through fluorescence detector. Temperature control of the column and the presence of Triton X-100 surfactant were critical for specific hybridization. Perfusion of the column with complementary oligonucleotide (200 μL, 10 nM) resulted in hybridiz...
Hybrid protein thymidine kinase gene fusions: plasmid vectors for the study of transcription and translation initiation signals

The thymidine kinase (TK) gene (tk) from Herpes simplex virus type 1 has been used to form gene fusions encoding enzymatically active hybrid proteins. The promoter, translation initiation region, and the first three codons of the tk gene were removed and replaced with a series of DNA restriction sites. DNA fragments containing gene initiation regions were cloned into these sites and shown to synthesize enzymatically active proteins in Escherichia coli. These gene fusions were shown to complement an E. coli strain which is deficient in TK function. Gene initiation regions were used from the lac operon, the tnpR gene of Tn3, and the insA gene of ISl. TK synthesis was regulated by the control signals of the promoter fused to tk, and was dependent upon the phase alignment of the codons at the fusion joint. The size of the resulting protein was shown to be increased over the size of the original TK protein by the length of the coding region fused to TK. This demonstrated that the tk gene has non-essential N-terminal amino acids that can be replaced by other amino acid sequences with the retention of TK enzymatic activity. Such tk gene fusions are useful in situations where fusions with other genes cannot be conveniently selected or assayed.
Transcutaneous electrical nerve stimulation for the relief of postoperative pain.

Abstract The pain-killing abilities of electricity were known as far back as the ancient Egyptians and Hippocrates, but it was not until 1965 when Melzack and Wall [10] proposed the “gate theory of pain” that clinical interest was re-awakened. This theory postulated that a “gate” for pain existed in the substantia gelatinosa of the posterior spinal horns and that modification of the perception of pain might be possible by blocking the “gate” with non-painful stimuli. They suggested that selective stimulation of large diameter myelinated cutaneous afferent nerve fibers could set a process in motion which would close the “gate” to information coming over smaller pain-carrying fibers. The first clinical application of this theory centered around the relief of chronic pain by surgical placement of dorsal column stimulators [1] and implantation of stimulating devices around large peripheral nerves to block pain sensations. Transcutaneous electrical nerve stimulation was first employed in an attempt to select patients for implantable devices and then as a therapeutic device to alleviate chronic pain [2,4,6,9,11]. The next logical step was to apply this modality to patients in the immediate postoperative period to decrease incisional pain. Hymes et al. [8] noted a decrease in atelectasis, ileus, postoperative pain and days spent in intensive care in patients using transcutaneous electrical stimulation. Vanderank and McGrath [9] reported that 77% of their patients treated with stimulators experienced some relief of postoperative pain.