cssi/SciSciGPT-SciSciNet huggingface dataset:
Type II DNA topoisomerases: Coupling directional DNA transport to ATP hydrolysis

Publisher Summary This chapter describes the mechanism of the type II enzymes and focuses on the present knowledge about the way these enzymes couple adenosine triphosphate (ATP) binding and hydrolysis to the directional transport of one duplex DNA segment through a transient break in another. Type II topoisomerases are essential in all organisms for unlinking replicated chromosomes and establishing the proper condensed state of these chromosomes. These enzymes are also the targets of many natural and man-made toxins, some of which are used as antimicrobials and chemotherapeutics. Type II topoisomerases require ATP to catalyze the directional transport of a T segment through a G segment. This directionality has been long appreciated for gyrase, the prokaryotic type II topoisomerase that uniquely introduces negative supercoils into DNA. Because gyrase increases the free energy of its DNA substrate, it is obvious why it requires ATP. However, the other type II topoisomerases, including all the known eukaryotic type IIA proteins, the bacteriophage enzymes, and prokaryotic topo IV cannot supercoil DNA. These enzymes, referred to as “topo II/IV” to distinguish them from gyrase, can all relax supercoiled DNA, bringing it to a lower-energy state, but cannot supercoil it. They can also catenate/decatenate and knot/unknot DNA circles.
A novel multimodal optical imaging system for early detection of oral cancer.

Objectives Several imaging techniques have been advocated as clinical adjuncts to improve identification of suspicious oral lesions. However, these have not yet shown superior sensitivity or specificity over conventional oral examination techniques. We developed a multimodal, multi-scale optical imaging system that combines macroscopic biochemical imaging of fluorescence lifetime imaging with subcellular morphologic imaging of reflectance confocal microscopy for early detection of oral cancer. We tested our system on excised human oral tissues. Study Design In total, 4 tissue specimens were imaged. These specimens were diagnosed as either clinically normal, oral lichen planus, gingival hyperplasia, or superficially invasive squamous cell carcinoma. The optical and fluorescence lifetime properties of each specimen were recorded. Results Both quantitative and qualitative differences among normal, benign, and squamous cell carcinoma lesions can be resolved with fluorescence lifetime imaging reflectance confocal microscopy. The results demonstrate that an integrated approach based on these two methods can potentially enable rapid screening and evaluation of large areas of oral epithelial tissue. Conclusions Early results from ongoing studies of imaging human oral cavity illustrate the synergistic combination of the 2 modalities. An adjunct device based on such optical characterization of oral mucosa can potentially be used to detect oral carcinogenesis in early stages.
Nitrogen photochemistry. Cocaine and its model compounds

The ultraviolet irradiation of the π π* transition of cocaine, p-anisoyl-l-ecognine methyl ester, p-toluoyl-l-ecognine methyl ester benzoyl tropine and benzoylpseudotropine in methanol using a Corex filter produces the corresponding N-demethylated products. Formaldehyde is quantitatively produced. 1-Methyl-3-piperidyl benzoate and 1-methyl-4-piperidyl benzoate yield benzoic acid under the same conditions but no demethylated products. Phenylacetyl-l-ecognine methyl ester gives no demethylation during irradiaiton. The phosphorescence bands of cocaine and its model compound, methyl benzoate, have been shown to be strongly dependent upon solvent polarity suggesting charge transfer in the triplet state.
Respiratory activity of adrenal cortex mitochondria during steroid hydroxylation

Abstract Mitochondria from the cortex of beef adrenal glands have been isolated and shown to oxidize a variety of tricarboxylic acid cycle substrates concomitant with the 11β-hydroxylation of deoxycorticosterone (DOC). These mitochondria possess a number of activities markedly different from those observed with mitochondria from liver, kidney, heart, etc. Although respiratory control ratios of two to three can be obtained during succinate oxidation, uncouplers or calcium ions stimulate respiration five- to sixfold. The low activity of dinitrophenol-stimulated ATPase suggests a deficiency in energy transfer reactions for ATP formation by adrenal cortex mitochondria favoring the diversion of energy for the support of hydroxylation reactions. This hypothesis is supported by measurements of DOC inhibition of ATP formation during succinate or malate oxidation. The influence of inhibitors on the function of the two types of respiratory chains present in adrenal cortex mitochondria, i.e., a normal cytochrome-containing respiratory chain and a cytochrome P-450-containing respiratory chain, reveals the role of an active malic enzyme. The stoichiometry of DOC hydroxylation demonstrates a ratio of corticosterone: O 2 of 1.1 when malate is used as substrate. Although present studies support a role for an energy-linked transhydrogenase during succinate supported oxidation and DOC hydroxylation, a proposed role for malic enzyme has been considered.
Voltage- and concentration-dependent effects of lidocaine on cardiac Na channel and Ca channel gating charge movements

The effects of lidocaine, a local anesthetic and cardiac antiarrhythmic agent, were studied on cardiac nonlinear Na channel and Ca channel charge movements (gating currents) of 17-day-old embryonic chick ventricular myocytes. Gating currents were recorded following the blockade of all ionic currents and the subtraction of the linear capacity currents (-P/5). From a holding potential of −100 mV the ON charge movement (Q ON) displayed two kinetic components: a rapidly decaying component associated with Na channel gating, and a slower component associated with Ca channel gating. A depolarizing prepulse to −50 mV for 125 ms reduced the fast component of Q ON, with little effect on the slower component. Similarly, 20 μM lidocaine also reduced the fast component of Q ON (Na channel charge movement) and had little effect on the slower component (Ca channel charge movement). Higher concentrations of lidocaine (125 μM) reduced both the fast and the slower components of Q ON. The effects of either a prepulse to −50 mV, or 20 μM lidocaine on the steady-state Q ON/V m relationship were nearly identical. These results suggest that lidocaine “blocks” cardiac Na (ionic) currents by a reduction in the availability of Na channel charge movement (Q ON), and that this reduction is similar to that produced by voltage-dependent inactivation.
AMO Inversion to a Common Azimuth Dataset

I cast 3-D data regularization as a least-squares inversion problem. I form a linear operator that maps from irregular dataspace 5-D data space to a regular 4-D common azimuth volume using a cascade of linear interpolation and Azimuth Move-out (AMO) binning. I regularize the inversion by adding minimizes the difference between various (t , cmpx , cmpy) cubes by applying a filter that acts along offset. AMO is used to transform the cubes to the same hx before applying the filter. Further efficiency is gained by inverting each frequency independently. I apply the methodology on marine dataset and compare the results with two more conventional approaches.
Do experiments that will help solve clinical problems

In the current interview, Professor Seiki Matsuno shares his experience and provides career advice to young investigators initiating in pancreatic research. Professor Matsuno is internationally recognized for his contributions to different areas of pancreatology, including the clinical characterization and treatment of pancreatic diseases.
Optimization of Aluminum Smelter Casthouse Operations

This paper presents a mixed-integer linear programming (MILP) model for the scheduling of a multistage process for the production of aluminum casts of different alloys, using parallel furnaces and casters. In contrast to the common approach in multistage models of considering a fixed set of orders being processed sequentially in the stages, the modeling approach in this paper accounts for actual material flows and, thus, provides flexibility with respect to the actual number of batches to be processed for meeting a given demand. This enables the model to handle parallel nonuniform units with variable capacities, where it is difficult to a priori decide on the number of batches that are required to satisfy the orders. The model also features a material balance over the furnace section, to capture processing details. A decomposition scheme that consists of a master problem and a sub-problem is developed and is used in an iterative algorithm to solve medium- to large-sized problems in reasonable computationa...
Bugs or Drugs: Are Probiotics Safe for Use in the Critically Ill?

Probiotics are living microorganisms which have demonstrated many benefits in prevention, mitigation, and treatment of various disease states in critically ill populations. These diseases include antibiotic-associated diarrhea, Clostridium difficile diarrhea, ventilator-associated pneumonia, clearance of vancomycin-resistant enterococci from the GI tract, pancreatitis, liver transplant, major abdominal surgery, and trauma. However, their use has been severely limited due to a variety of factors including a general naivete within the physician community, lack of regulation, and safety concerns. This article focuses on uses for probiotics in prevention and treatment, addresses current concerns regarding their use as well as proposing a protocol for safe use of probiotics in the critically ill patient.
A quantitative approach to logical inference

Abstract Logical inference is of central importance in the information and decision sciences but presents a very hard computational problem. Since the traditional symbolic inference methods have had limited success on large knowledge bases, this papers investigates a quantitative approach. It surveys the application of integer programming methods to inference problems in propositional logic. It displays a number of remarkable parallels between logic and mathematics and shows that these can lead to fast inference methods, both quantitative and symbolic. In particular it explains why the logical concepts of resolution, extended resolution, input and unit refutation, the Davis-Putnam procedure, and drawing of inferences pertinent to a given topic are closely related to the mathematical concepts of cutting planes, Chvatal's method, elementary closure, branch and bound, and projection of a polytope, respectively. Much of the paper should be intelligible to persons with limited background in logic and mathematical programming, but recent mathematical results are stated precisely.
Global Integrability Theorems for A-Harmonic Tensors

Abstract We extend global integrability theorems for the gradients of A -harmonic functions to the exterior derivative of differential forms satisfying rather general nonhomogeneous elliptic equations. These include the usual A -harmonic equations. Geometric conditions on the boundary of the domains of integration imply a corresponding exponent of integrability. In the process we generalize the weak reverse Holder inequality to such differential forms.
Getting The Most Out of Your Research

Research is the cornerstone of invention, facilitator of innovation, and mother of discovery. Even though many students are competent in advancing through the class room and getting good grades, excellent research requires a different set of attitudinal and academic skills. This workshop, "Get the most out of your research" is an outstanding program developed from extensive time spent with brilliant scientists and a wide variety of mentored students. Familiarize yourself with the fine points of this workshop and arm yourself for a successful research career.
Studies of the structure of molybdenum oxide and sulfide supported on thin films of alumina

The morphology of monolayer quantities of molybdenum oxide and sulfide phases supported on thin films of nonporous alumina was studied by X-ray photoelectron spectroscopy and conventional and scanning transmission electron microscopy. Following oxidation at 770 K, a strong oxide-support interaction was observed, resulting in a highly dispersed molybdenum phase for loadings below ca. 5 Mo atoms nm−2. The molybdenum oxide-support interaction was broken by sulfiding in H2SH2 at ca. 770 K, with the formation of faceted single crystallites of MoS2. The MoS2 crystallites were present as hexagonally shaped slabs with one truncated edge and they were bonded with their high-energy edge planes to the alumina surface. The edge planes contacting the gas phase were the 1010 set of planes, while the truncated edge bonded to the surface of alumina was the 2110 plane. After 910 K sulfidation, the particles became larger, and many were oriented with their basal planes parallel to the support. Reoxidation at 770 K redispersed the crystallites due to spreading of molybdenum oxide over alumina. These results can be explained by the formation of MoOAl linkages during oxidation and the breaking of these linkages during sulfiding. As these linkages that anchor the MoS2 crystallites to the support are broken, the MoS2 basal planes become oriented at angles close to 90 ° to the support surface. Upon more extensive sulfidation, the MoS2 crystallites became oriented with their basal planes parallel to the support when the MoOAl linkages at the edge plane are finally broken.
A New Fast Algorithm to Estimate Real-Time Phasors Using Adaptive Signal Processing

Phasor magnitude and angle of various harmonic and interharmonic components of the power signal are widely used as critical variables and performance indices for power system applications, such as protection, relaying, and state monitoring. This paper proposes a novel adaptive algorithm for estimating the phasor parameters in real time. It uses a faster quasi-second-order optimization technique to estimate amplitude and phase and does not require any matrix inversions. It features fast response, achieves high accuracy, and involves less computational complexity than many other models and window-based methods.
Development of Energy Balances for Fixed-Bed Adsorption Processes: Thermodynamic Paths, Heat Capacities and Isosteric Heats

This paper provides a simplified treatment of the method of Walton and LeVan (2003) for the development of energy balances for bidisperse particles in fixed-bed adsorption using thermodynamic paths. When adsorbed-phase enthalpy is properly defined, terms involving reference states cancel out of the energy balance, and only gas-phase heat capacities appear in the equation. Calculations show that adsorbed-phase heat capacities may deviate significantly from gas-phase heat capacities when the isosteric heat has a relatively small temperature dependency. Thus, special attention should be given to the path used to derive the energy balance to avoid inconsistencies in heat capacity definitions.
Giardia lamblia trophozoites contain multiple alleles of a variant-specific surface protein gene with 105-base pair tandem repeats.

Abstract Giardia lamblia trophozoites undergo antigenic variation of a variant-specific surface protein (VSP). All VSPs that have been reported have had high cysteine contents, including numerous copies of a CXXC motif. The first vsp gene described (vspA6; from the cloned line, WBA6), contained 21 copics of a 195 base pair tandem repeat, but other reported VSPs have not contained repeats. In this report, we describe the vsp gene from WBC5, a cloned line derived from WBA6. The vspC5 gene contains short 5′ and 3′ regions flanking 26 copies of a 105-bp tandem repeat, which comprises 93% of the coding region. In addition to the copy containing 26 repeats, the genome contains other copies of the vspC5 with fewer copies of the repeat. The sequences flanking the repeats are identical, and all copies map to the same location on chromosomal Band 5. suggesting that multiple alleles of the vspC5 gene are present.
Multi-Dimensional Electronic Spectroscopy of J-Aggregates

Multi-dimensional electronic spectroscopy, via spatiotemporal pulse-shaping, is used to study excitons in J-aggregates. Correlation spectra elucidate spectral diffusion while a two-quantum experiment reveals couplings between the first and second manifolds of exciton states.
Responding to AIDS-Related Bereavement in the South African Context

AIDS continues to be a death sentence for many individuals living in South Africa where it remains the leading cause of death. Little is currently known about what it is like to experience the loss of a loved one to AIDS from the South African perspective and how to assist individuals who are living in a context vastly different from similarly bereaved individuals in the West. The purpose of this article is to discuss contextual issues that may affect individuals in South Africa who are grieving AIDS-related deaths and to offer preliminary suggestions on how to help these individuals. The author draws on his experience in the province of KwaZulu-Natal working with people affected by the HIV/AIDS epidemic, as well as discussions with practitioners involved in HIV/AIDS care in this region.
Using chromaflo intra-vascular ultrasound (IVUS) to analyze adventitial vasa vasorum distribution : Considerations and recommendations

The adventitia and outer media of large blood vessels are supplied with nutrients by microscopic blood vessels called vasa vasorum. While vasa vasorum have been implicated in a number of diseases including atherosclerosis, knowledge of their functional anatomy and specific role in these diseases has been hindered due to the small size of the vasa vasorum, and difficulty in accessing them. Micro-CT and histological methods have been used in ex-vivo animal studies of the vasa vasorum, but these techniques are limited by their inability to be used for in-vivo investigation. As such, there is very little in-vivo human data available. Intra-vascular ultrasound can acquire high-resolution anatomic images of coronary vessels. ChromaFlo IVUS has been used to identify blood flow in vessel lumens and has exciting prospect for in-vivo studies of vasa vasorum functional anatomy. In this study, ChromaFlo IVUS images of the human mid-left anterior descending coronary artery (LAD) were segmented to analyze the distribution of adventitial vasa vasorum proximal to intimal plaque. Previous animal studies suggest that formation of intimal plaque is accompanied by increased density of adventitial vasa vasorum. The data collected with ChromaFlo ultrasound is inconsistent with the current literature. While IVUS has the fidelity to acquire high-resolution US images of the coronary arteries, ChromaFlo lacks the necessary resolving power to differentiate the vasa vasorum. Further study of IVUS and other imaging methods on a large cohort will provide the basis for future in-vivo analysis of coronary disease.
The effects of unsteady aerodynamics on single and clustered parachute systems

A study was performed to evaluate the performance of equivalent drag area single parachute systems and cluster parachute systems during the early inflation and initial deceleration phase. Analytical work showed that the cluster system could exhibit better performance during this unsteady aerodynamic phase due to a significant decrease in the apparent mass of air influenced by the parachutes. Two test programs have been performed in support of these assumptions. The first compared systems with parachute drag areas of approximately 750 ft/sup 2/ and a payload of 2400 lbs. The cluster system exhibited increased performance and less susceptibility to parachute collapse due to wake recontact. The second series compared systems with parachute drag areas of approximately 260 ft/sup 2/ with a payload of 800 lbs. The advantages of the cluster system were less apparent but performance was moderately improved. 4 refs., 7 figs.
M.I.D.A.S. touch: magnetic interactive device for alternative sight through touch

This paper describes the development of a working prototype of a novel free-space haptic human-computer interface called MIDAS Touch. MIDAS Touch works by applying physical forces to a user's finger through the production of a dynamic magnetic field. The magnetic field strength is adjusted in real-time based on the user's movement of his/her finger. A user's hand/finger motion in the real world is mapped to movement of a virtual finger in a virtual world through the use of a Leap Motion 3D tracking sensor. As a person's virtual finger collides with objects in the virtual world, the magnetic field strength is varied. In this demo, we present a case of MIDAS Touch coupled to a standard PC as a computer drawing viewer and drawing application for helping individuals with visual impairment feel what they or others have drawn.
Effect of Coal Liquefaction Solvents on Fatigue Crack Initiation in 2 1/4 Cr-1 Mo Steel and 316L Stainless Steel

Blunt notch fatigue crack initiation tests were carried out on 2.25 Cr – 1 Mo steel and 316L stainless steel in room temperature air and in the process solvent from the Wilsonville, Alabama coal liquefaction pilot plant at 100°C. The crack initiation lifetime in the coal liquids at 100°C was an order of magnitude greater than the crack initiation lifetime in air for the 2.25 Cr–1 Mo steel. The crack initiation lifetime in the coal liquids for the 316L stainless steel was increased a factor of five over the crack initiation lifetime in air. The improvement in crack initiation lifetime was attributed to the coal liquids shielding the materials from atmospheric embrittlement. The coal liquids did not show any tendency to form sulfide corrosion products at 100°C.
p/+/-n-n/+/ solar cells with hole diffusion lengths comparable with the base width - A simple analytic model

A simple analytic description of the hole current injected into the n-n+ base of a p+-n-n+ solar cell under forward bias in the dark is derived for the intermediate case in which the hole diffusion length is comparable with the base width. The derivation is made possible by recognizing a common relationship between the effective surface recombination velocity at the n-n+ junction and the diffusion velocity in the base.
A Nationwide Analysis of Changes in Severity and Outcomes of Inflammatory Bowel Disease Hospitalizations

The past decade has seen a change in inflammatory bowel disease (IBD; Crohn's disease (CD) and ulcerative colitis (UC)) treatment, with increasing use of immunomodulators and biologics. The impact of this on IBD hospitalization outcomes is unknown. We identified hospitalizations with a diagnosis of IBD using data from the Nationwide Inpatient Sample, a national US discharge database. We compared the proportion of hospitalizations resulting in surgery in the entire cohort and within each disease severity stratum for the years 1998, 2004, and 2007. There were an estimated 89,673 hospitalizations for CD in 1998 increasing to 150,593 hospitalizations in 2007. UC hospitalizations increased from 56,911 in 1998 to 86,611 in 2007. This increase was primarily among low or intermediate severity hospitalizations not requiring surgery. For CD, the proportion of bowel surgeries during hospitalization decreased from 17.3% in 1998 to 12.4% in 2007 (p < 0.001) while for UC, the proportion of colectomy decreased from 9.5% in 1998 to 6.2% in 2007 (p < 0.001). For both diagnoses, this reduction was significant in those with a low severity of disease but not with in those with the highest severity stratum. There continues to be an increase in the number of hospitalizations in patients with IBD. The numbers of non-elective bowel surgeries among those with the highest severity of disease continues to increase suggesting need for further research into improving outcomes in this cohort at high risk for adverse outcome.
Limits on volume changes in the mushroom bodies of the honey bee brain.

The behavioral maturation of adult worker honey bees is influenced by a rising titer of juvenile hormone (JH), and is temporally correlated with an increase in the volume of the neuropil of the mushroom bodies, a brain region involved in learning and memory. We explored the stability of this neuropil expansion and its possible dependence on JH. We studied the volume of the mushroom bodies in adult bees deprived of JH by surgical removal of the source glands, the corpora allata. We also asked if the neuropil expansion detected in foragers persists when bees no longer engage in foraging, either because of the onset of winter or because colony social structure was experimentally manipulated to cause some bees to revert from foraging to tending brood (nursing). Results show that adult exposure to JH is not necessary for growth of the mushroom body neuropil, and that the volume of the mushroom body neuropil in adult bees is not reduced if foraging stops. These results are interpreted in the context of a qualitative model that posits that mushroom body neuropil volume enlargement in the honey bee has both experience-independent and experience-dependent components.
Explicit Filtering and Reconstruction Turbulence Modeling for Large-Eddy Simulation of Neutral Boundary Layer Flow

Abstract Standard turbulence closures for large-eddy simulations of atmospheric flow based on finite-difference or finite-volume codes use eddy-viscosity models and hence ignore the contribution of the resolved subfilter-scale stresses. These eddy-viscosity closures are unable to produce the expected logarithmic region near the surface in neutral boundary layer flows. Here, explicit filtering and reconstruction are used to improve the representation of the resolvable subfilter-scale (RSFS) stresses, and a dynamic eddy-viscosity model is used for the subgrid-scale (SGS) stresses. Combining reconstruction and eddy-viscosity models yields a sophisticated (and higher order) version of the well-known mixed model of Bardina et al.; the explicit filtering and reconstruction procedures clearly delineate the contribution of the RSFS and SGS motions. A near-wall stress model is implemented to supplement the turbulence models and account for the stress induced by filtering near a solid boundary as well as the effect...
Defect Formation in Boron Carbide-An ab-initio Electronic Structure Study

The electronic structure of a crystalline boron carbide has an energy forbidden gap of ∼ 3 eV and is hence a good insulator. But, on the other hand, the electrical conductivity of boron carbide is measurable. It is therefore believed that the defects formation in boron carbide is responsible for its electrical conductivity and a theory of hopping conduction of bipolaron through localized defects were developed, accordingly. Although the bipolaron electrical conductivity model does not rely on any specific type of defect, the bipolaron formation in boron carbide is believed to be a defective CBB intraicosahedral chain in connection with an B 11 C icosahedron. The current study examined the existing theory of bipolaron electrical conductivity by performing a systematical study on the formation energies of the defects in boron carbide using a state-of-the-art ab-initio electronic structure method. The studied defects cover a) stoichiometric variations of carbon concentration, b) missing boron atoms, and c) distribution of carbon atoms in the materials. It is found that the ground state of a fully carbonated boron carbide consists of B 11 C icosahedra connected by CBC intraicosahedral chains, i.e. consistent with the reported structural model of B 4 C . When carbon concentration is reduced, however, the population of CBC chain is found to be intact, while the population of B 11 C icosahedron is reduced by the replacements of B 12 icosahedron. This observation is fundamentally different from the existing model of boron-rich boron carbide. The localized states associated with missing boron atoms are identified and the electrical conductivity through these localized defects states is studied.
Settling characteristics of microparticles modified by hydrophilic semi‐interpenetrating polymer networks

Microparticles of 2-hydroxyethyl methacrylate cross-linked with ethylene glycol dimethacrylate were produced by suspension polymerization. Semi-interpenetrating polymer networks were prepared by diffusion of poly(ethylene oxide) (PEO) solution into the particles. The PEO was allowed to diffuse into the dried particles and the resulting swollen particles were treated with an excess of acetone to collapse them. The ensuing networks consisted of the collapsed particles and the trapped PEO. The modified particles were allowed to settle in water, and characteristic settling times were measured as a function of swelling time. The settling times were compared to those of the unmodified particles. It was found that the settling time changes with volume fraction, particle size, degree of functionality, and amount of swelling. An increased volume fraction in both unmodified and modified particles causes a slower settling rate. The smaller particle sizes fall more slowly, and size difference plays a more significant role in hindering the settling for lower amounts of trapped PEO. As the amount of PEO increases, the settling rate decreases dramatically. Swelling also slows the settling rate, until the particles reach equilibrium. Equilibrium swelling occurs near 10 min for both unmodified and modified particles. Optical photo-microscopy verified the amount of swelling and demonstrated the process of PEO penetration. © 1995 John Wiley & Sons, Inc.
Intramuscular Injection of Ascorbic (Cevitamic) Acid and Excretion in the Sweat

Conclusions1. Cevitamic acid, properly buffered, may be administered intramuscularly without discomfort or damage to tissue. 2. Studies of the urinary excretion and the blood content of vitamin C following the administration of cevitamic acid intramuscularly demonstrated that it is used by the body when administered by this route. 3. The height of increase in the blood level following the intramuscular injection of cevitamic acid is reached more slowly and is maintained for a longer time than after intravenous injections. 4. In cases of vitamin C deficiency, where cevitamic acid is improperly absorbed through the gastro-intestinal tract, or where the intravenous mode of administration is not feasible, the intramuscular route may be used.
Tetra-2,3-pyrazinoporphyrazines with externally appended pyridine rings. 1. Tetrakis-2,3-[5,6-di(2-pyridyl)pyrazino]porphyrazine: a new macrocycle with remarkable electron-deficient properties.

A new pyrazinoporphyrazine macrocycle carrying externally appended pyridine rings, tetrakis-2,3-[5,6-di(2-pyridyl)pyrazino]porphyrazine (hydrated), [Py8TPyzPzH2]·2H2O, was prepared in high yield by direct cyclotetramerization of the precursor, 2,3-dicyano-5,6-di(2-pyridyl)-1,4-pyrazine, [(CN)2Py2Pyz], in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). The single-crystal X-ray structure of [(CN)2Py2Pyz] shows a noncoplanar positioning of the pyrazine and pyridine rings in the two slightly different independent molecular units present in the crystal. UV−vis spectra of [Py8TPyzPzH2] were measured in two nondonor solvents (CHCl3, CH2Cl2), a slightly basic solvent (pyridine), and an acidic solvent (CH3COOH). In all cases, the spectral changes are consistent with the occurrence of molecular aggregation and colloidal dispersions which break up with time to give clear solutions containing exclusively the monomeric form of the macrocycle, either neutral [Py8TPyzPzH2] (in CHCl3, CH2Cl2, and CH3COOH) or di...
Virginiamycin as an Antibiotic for Poultry Feeds

ANTIBIOTICS are widely used at low levels in commercial feeds to improve the early growth-rate of chickens and turkeys. The amount of response obtained from these drugs appears to be related to the nature and density of the microflora present in the feed and environment1.
A UTILITY MAXIMIZING MODEL OF THE DEMAND FOR MULTI-DESTINATION NON-WORK TRAVEL

Abstract In this paper, a structural model of the demand for multi-destination non-work travel is developed, and an empirical illustration of the structural model is presented. The structural model is based on the principle of utility maximization and differs from previous utility maximizing models of multi-destination non-work travel in several important ways. In contrast to most previous models, the model presented here incorporates travel frequency, destination choice and mode choice for both single and multi-destination travel into a unified utility-maximizing framework. The model includes a representation of the demand for travel between individual origin-destination pairs but avoids the need for enumerating complete travel patterns. Finally, the model incorporates the concept that current travel decisions depend on past travel decisions and future travel plans, as well as on current conditions. Empirical tests of the model have produced encouraging results concerning the model's structural validity. The empirical tests also have indicated that there is a need to develop improved sets of explanatory variables for non-work travel.
Trends in opioid use over time: 1997 to 1999.

Substantial resources have been spent to improve pain control for dying patients, and increased opioid administration has been presumed. Oregon has been a consistent leading state in per capita use for morphine for the past 10 years, as recorded by the Automation of Reports and Consolidated Orders System (ARCOS). Health policy experts, extrapolating from World Health Organization methods, have suggested these data are indicative of the quality of end-of-life care in Oregon. To determine whether trends in opioid prescription at the state and national levels reflect increased opioid use for inpatients during the final week of life, chart reviews were conducted to record all opioid medications administered in the last week of life to 877 adult inpatients who died from natural causes between January 1, 1997 and December 31, 1999. Inpatient morphine use did not increase significantly for dying patients from 1997 to 1999. However, overall morphine use for both Oregon and the United States as measured by ARCOS d...
Mitochondrial Ca2+ uptake prevents desynchronization of quantal release and minimizes depletion during repetitive stimulation of mouse motor nerve terminals

When motor nerve terminals are stimulated repetitively, cytosolic [Ca2+] increases to a plateau amplitude that is maintained as long as stimulation persists (Wu & Betz, 1996; Ravin et al. 1997; David et al. 1998, David & Barrett, 2000; Suzuki et al. 2000). Mitochondrial Ca2+ uptake contributes importantly to limiting the increase in cytosolic [Ca2+], because when this uptake is inhibited by depolarizing the electrical potential across the inner mitochondrial membrane (Ψm), cytosolic [Ca2+] increases to much higher levels during stimulus trains (Tang & Zucker, 1997; David et al. 1998; David & Barrett, 2000; Suzuki et al. 2002). Similar effects of Ψm depolarization on stimulation-induced cytosolic [Ca2+] responses have also been observed in other nerve terminals, neuronal somata and certain secretory cells (Friel & Tsien, 1994; Steunkel, 1994; Werth & Thayer, 1994; White & Reynolds, 1995; Herrington et al. 1996; Sidky & Baimbridge, 1997; Medler & Gleason, 2002). Mitochondrial Ca2+ uptake is passive, mediated by a uniporter in the inner mitochondrial membrane and powered mainly by the Ψm created by the electron transport chain (reviewed in Gunter & Pfeiffer, 1990). This study investigated how mitochondrial Ca2+ uptake affects quantal transmitter release from mouse motor nerve terminals, using Ψm depolarizing drugs to block this uptake. Previous studies reported that these drugs increase the rate of asynchronous release recorded from resting frog, snake, crayfish and cockroach motor terminals, and increase the quantal content of phasic release evoked by nerve stimulation (Alnaes & Rahamimoff, 1975; Washio, 1982; Molgo & Pecot-Dechavassine, 1988; Zengel et al. 1994; Tang & Zucker, 1997; Calupca et al. 2001). Both of these effects were attributed to an increase in cytosolic [Ca2+], which would be predicted to increase asynchronous release directly, and to increase phasic release by a ‘residual Ca2+’ mechanism such as that postulated to mediate short-term historical processes such as facilitation. However, the studies of phasic release in vertebrate nerve terminals reduced Ca2+ influx into stimulated terminals by using low bath [Ca2+] to prevent muscle contraction. In addition, none of these preceding studies measured asynchronous release during the stimulus train, when the large increase in cytosolic [Ca2+] during Ψm depolarization might be predicted to have its major effect. We present evidence that blocking mitochondrial Ca2+ uptake by Ψm depolarization markedly increases both EPP depression and asynchronous release during 50 Hz stimulation. Therefore, the ability of mitochondria to sequester Ca2+ and thus prevent large increases in cytosolic [Ca2+] is essential to prevent desynchronization of release during repetitive stimulation.
A High Performance Liquid Chromatographic Method for the Determination of Rapamycin (Sirolimus) in Rat Serum, Plasma, and Blood and in Monkey Serum

Abstract A high performance liquid chromatographic (HPLC) method was developed for the quantitation of rapamycin, an immunosuppressive agent, in biological specimens. The method employs a 15 cm Supelco LC-18 column (5 μm) interconnected to a 25 cm Supelco LC-18 column (5 μm). The mobile phase is a methanol/water gradient system. The flow rate is 0.51 ml/min and detection is by ultraviolet (UV) absorption at 276 nm. The method was validated for its specificity, precision, linearity and sensitivity in rat serum. Endogenous compounds in rat serum did not interfere with the detection of rapamycin or the internal standard (β-estradiol-3-benzoate). Based on a 1.0 ml serum sample, the assay was linear from 5 to 500 ng/ml. The intra-day coefficients of variation were below 10% and independent of concentration. Inter-day precision values ranged from 5.5 to 13.6%, the difference being independent of concentration. The specificity, linearity and sensitivity of the method was also demonstrated in cynomolgus monkey se...
Scientific Objectives of Mohole, and Predicted Section: ABSTRACT

The major scientific objective of the AMSOC project is to obtain samples of the upper part of the earth's mantle and to determine the nature of the Moho discontinuity. Boisse's analogy of 1850 suggesting that meteorites were a fair approximation of the composition of the earth's interior was a brilliant idea for its day, but is too inexact for present purposes. Above the discontinuity is a layer commonly called the "crust" and generally considered to be basalt. It is extraordinarily uniform in thickness suggesting that its base represents a phase transition and that the Moho under the oceans might represent the level of some isotherm, or past isotherm, at which a reaction took place. Above the "crust" is a layer of variable thickness and seismic velocity thought to be consolidated sedimentary or volcanic rocks. Finally one comes to the unconsolidated sediments of the ocean floor which are a few hundred meters thick and no doubt resemble the material obtained from shallow cores. In these last two layers one might hope to find fossils going far back in the history of the oceans and to derive from this record information of extraordinary scientific importance. The following predictions are made. (1) The mantle will be peridotite resembling the olivine nodules found in basaltic volcanoes and St. Paul's rock. (2) The "basalt crust" will be serpentinized peridotite, hydrated mantle material. (3) The Moho discontinuity represents a past isotherm above which serpentine was a stable phase. (4) The sedimentary column will be very incomplete and have many great hiatuses. End_of_Article - Last_Page 1250------------
Effect of an Intensive Exercise Intervention Strategy on Modifiable Cardiovascular Risk Factors in Subjects with Type 2 Diabetes Mellitus

Introduction: Low cardiorespiratory fitness (CRF) and physical inactivity are associated with higher rates of cardiovascular disease (CVD), morbidity, and mortality among individuals with type 2 diabetes mellitus (T2DM). Lifestyle modification interventions, including physical activity, have proven effective in glycemic control and reducing cardiovascular risk factors within this population. The American Diabetes Association follows the same recommendations for individuals with impaired glucose tolerance (IGT) or T2DM as is recommended for the general population, which is 150 min/wk of moderate intensity, 75 min/wk of vigorous physical activity, or a combination of moderate and vigorous with 1 min of vigorous being equal to 2 min of moderate. However, it is uncertain whether this physical activity volume is optimal to reduce the CVD burden among individuals with IGT or T2DM.
SEQUENTIAL CHANGES IN SERUM INSULIN CONCENTRATION DURING DEVELOPMENT OF NON-INSULIN-DEPENDENT DIABETES

Changes in serum insulin concentrations during deterioration of glucose tolerance were studied in 81 Pima Indians who worsened from normal to impaired glucose tolerance (IGT); 44 who changed from IGT to non-insulin-dependent diabetes mellitus (NIDDM); 27 who were seen at diagnosis of NIDDM and 1.4-8.5 years later; and 11 subjects who were seen at each of these stages. When their glucose tolerance was normal, subjects who later developed NIDDM had higher fasting and post-load insulin concentrations than controls of similar age and body mass index who did not become diabetic. Onset of IGT or NIDDM was associated with a further increase in fasting insulin concentrations, although a deterioration from IGT to NIDDM was associated with little change in insulin responses to oral glucose in spite of increased blood glucose. After the onset of NIDDM, both fasting and post-load insulin concentrations diminished. These longitudinal data show that, as glucose tolerance worsens, insulin and glucose concentrations in individuals follow the inverted-U-shaped relation previously reported in cross-sectional population studies.
Control of the Unsteady, Separated Flow Behind an Oscillating, Two-Dimensional Flap

Methods of passive and active open-loop control of the unsteady, separated flow produced downstream of a two-dimensional lifting flap have been examined. Phase-averaged, unsteady pressure measurements were used to measure the effect of the control on both the unsteady vortex formed as the flap lifts from the tunnel floor and the steady separation formed when the flap remains in the vertical position. The passive control experiments used twc- and three-dimensional disturbances upstream of and at the separation line located at the trailing edge of the flap. Due to the fixed separation line of the flap, the unsteady vortex was not changed by the passive control, however significant increases were obtained in the pressure recovery for the steady separation. Using pulsed blowing and suction, the active control experiments were able to reduce the suction peak of the unsteady vortex by as much as 40% and delay the peak suction by 14 milliseconds in addition to increasing the pressure recovery in the steady separation. A simple model for estimating the x-position, y-position, and circulation of the unsteady vortex using the measured pressures shows good agreement with vortex properties calculated using detailed velocity measurements.
Bicriterion jobshop scheduling with total flowtime and sum of squared lateness

Abstract In this paper sufficient conditions for optimality for the single machine job scheduling problem with a linear combination of total flowtime and sum of squared lateness as the objective function are developed. Based on the sufficient conditions a lower bound for the objective function for a given schedule is derived. A branch-and-bound procedure incorporating the lower bound has also been developed. In addition, we also show how to fathom nodes in the branching tree using the a-priori precedence relationships among the jobs that can be determined using the sufficient conditions. Computational experiments for the branch-and-bound and its results are also presented.
Studies toward the total synthesis of sorangiolides and their analogues. A convergent stereoselective synthesis of the macrocyclic lactone precursors.

Stereoselective synthesis of the fully protected 18-membered macrocyclic lactones as the immediate precursors of the natural products, sorangiolides A and B, is described. The key steps used in the synthesis include the sp3-hybridized carbon−carbon Fu cross coupling, the stereoselective Evans' aldol reaction with 1,5-anti induction, the 1,3-diastereoselective syn reduction of a β-hydroxyketone intermediate, and Mukaiyama macrolactonization reactions.
Performance characteristics of large aperture, ten-cell atmospheric pressure isobutane Cherenkov counters

Abstract Two large-aperture, 10-cell atmospheric-pressure isobutane Cherenkov counters were designed and constructed for a SLAC streamer-chamber experiment. The rejection efficiencies for a 9 GeV/cπ− were measured to be 99.84% ⋍ 0.006% and 99.717% ± 0.008% for the two counters. The design details and performance characteristics are discussed.
Nucleation and Crystallization of NaNbO3 from Glasses in the Na2O‐Nb2O5‐SiO2 System

Transparent glass-ceramics, in which the major phase was NaNbO3, were obtained by heat treatment of glasses in the Na2O-Nb2O5-SiO2 system. The structure of the glass and the changes occurring during crystallization as a function of temperature and heating rate were examined by X-ray diffraction, transmission and replication electron microscopy, density, and other measurements. On heating, a rather abrupt formation of uniformly dispersed particles was observed. In the early stages of crystallization, these particles contained NaNbO3 as loose, radially grown dendrites of identical crystal orientation which became dense during later stages of crystallization. The particle sizes ranged from 200 to 10,000 A, depending on the SiO2 content of the glass. Transparency of the crystallized material was dependent on the particle size rather than on the amount of NaNbO3 formed. The temperature at which crystallization occurred increased with the heating rate whereas the viscosity at crystallization decreased. For a given value of the rate of crystal formation per °C of temperature increase, the product (viscosity)n× (heating rate) was constant. The nucleation and growth phenomena which occurred in these glasses was attributed to microheterogeneities of higher Nb2O5 content which formed part of the glass structure.
A temporal model of patient disclosure in psychotherapy

Abstract The primary aim of this study was to identify the temporal elements of patient self-disclosure in psychotherapy. Twenty-one patients in individual psychotherapy participated in a semistructured interview that explored issues related to the intrinsic decision-making process and the emotional experiences involved in disclosing intimate concerns and secrets in therapy; they also completed several Likert-type questions focused on feelings experienced after disclosures. Results indicate a general sequence of events within the disclosure process: (a) a generally positive attitude toward disclosure; (b) ambivalence before disclosure; (c) vulnerability during disclosure; (d) primarily positive emotional experiences immediately after disclosure; (e) a search for and receipt of therapist approval after disclosure; and (f) increased likelihood of future disclosures to therapists and others. The data suggest that, whereas distressful feelings (e.g., shame) often precede and accompany self-disclosure, positiv...