cssi/SciSciGPT-SciSciNet huggingface dataset:
Occurrence of “never events” after major open vascular surgery procedures

Objective "Never events" refers to harmful hospital-acquired conditions that the Centers for Medicare and Medicaid Services identified in 2008 as largely preventable and that would no longer be reimbursed. Our goal was to identify the incidence, predictive factors, temporal trend, and associated consequences of never events after major open vascular surgery procedures. Methods The Nationwide Inpatient Sample (NIS) (2003-2011) was queried to identify never events applicable to vascular surgery patients, including air embolism, catheter-based urinary tract infections (UTIs), stage 3 and 4 pressure ulcers, falls/trauma, blood incompatibility, vascular catheter infections, complications of poor glucose control, retained foreign objects, and wrong-site surgery. We specifically evaluated open abdominal aortic aneurysm repair, carotid endarterectomy, and lower extremity bypass/femoral endarterectomy. Multivariable logistic regression was used to predict never events based on preoperative variables. Multivariable logistic and gamma regression models were used to study mortality, hospital length of stay (LOS), and charges. Results Never events were identified in 774 of 267,734 patients. The distribution of never events were falls/trauma (59%), pressure ulcers (19%), catheter-based UTI (9%), vascular catheter infection (6%), complications of poor glucose control (5%), and retained objects (4%). Rates of falls and catheter-based UTIs have increased since 2008. Multivariable predictors of any never event included lower extremity bypass, abdominal aortic aneurysm, weight loss, nonelective admission, paralysis, repair, congestive heart failure, altered mental status, renal failure, weekend admission, diabetes, female gender, and age. Race, insurance, hospital type, income level, geography, July to September admission, and other comorbidities were not predictive. After risk factor adjustment, never events were associated with increased perioperative mortality (odds ratio, 2.7; 95% confidence interval [CI], 1.5-34.8; P P P Conclusions Never events after major vascular surgery are associated with a number of perioperative factors and are predictive of increased charges, LOS, and mortality. Falls and catheter-based UTIs have increased in frequency since the Centers for Medicare and Medicaid Services announced that it would no longer reimburse for these complications. This study establishes baseline never event rates in the vascular surgery patient population and identifies high-risk patients to target for quality improvement.
Novel genetically encoded biosensors using firefly luciferase.

Genetically encoded biosensors have proven valuable for real-time monitoring of intracellular phenomena, particularly FRET-based sensors incorporating variants of green fluorescent protein. To increase detection sensitivity and response dynamics, we genetically engineered firefly luciferase to detect specific intermolecular interactions through modulation of its luminescence activity. This concept has been applied in covalent, noncovalent, and allosteric design configurations. The covalent design gives sensitive detection of protease activity through a cleavage-dependent increase in luminescence. The noncovalent and allosteric designs allow reversible detection of the small molecules rapamycin and cAMP, respectively. These sensors allow detection of molecular processes within living cells following addition of the luciferin substrate to the growth medium. For example, the cAMP sensor allows monitoring of intracellular signal transduction associated with G-protein coupled receptor function. These and other...
An Expert Vision System for Medical Image Segmentation

In this paper, an expert vision system is proposed which integrates knowledge from diverse sources for tomographic image segmentation. The system miinicks the reasoning process of an expert to divide a tomographic brain image into semantically meaningful entities. These entities can then be related to the fundamental biomedical processes, both in health and in disease, that are of interest or of importance to health care research. The images under study include those acquired from x-ray CT (Computed Tomography), MRI (Magnetic Resonance Imaging), and PET (Positron Emission Tomography). Given a set of three (correlated) images acquired from these three different modalities at the same slicing level and angle of a human brain, the proposed system performs image segmentation based on (1) knowledge about the characteristics of the three different sensors, (2) knowledge about the anatomic structures of human brains, (3) knowledge about brain diseases, and (4) knowledge about image processing and analysis tools. Since the problem domain is characterized by incomplete and uncertain information, the blackboard architecture which is an opportunistic reasoning model is adopted as the framework of the proposed system.
The effect of temperature on the critical failure properties of advanced polymer composites

Abstract The effect of temperature on the critical failure properties of three advanced polymer composites from the polyimide family have been investigated. The matrix resins under investigation were PMR-15, matrimid 5292 BMI and PMR-II-50. Celion G30–500 satin weave carbon fabric with 3 K filament per toe was used to reinforce (0↓rr90↑rr)s the polymers. The fiber volume ratio was kept constant at about 0·6 in all three composites. Flexural tests were conducted on multiple identical beam specimens from each composite system at 26°, 121° and 260°C (205°C for BMI). The tests were performed on both unnotched and notched specimens in the translaminar and crosslaminar directions. The critical failure properties such as flexural strength, toughness and the resistance to delamination have been evaluated at each temperature. The effect of temperature is most evident in PMR-15, which shows a considerable decrease in its ultimate flexural strength and stiffness in both the translaminar and crosslaminar directions. This is attributed to softening of its matrix at elevated temperature. The BMI and PMR-II-50 composites also exhibit overall decreases in their critical failure properties from room temperature to 260°C (205°C for BMI). Although the BMI composite is the weakest among the three tested composites, it is the least sensitive to temperature. Correlations between the failure modes, temperature and the stress at the onset of delamination of each composite have been developed.
Nuclear energy: The plutonium problem

The British government spends billions guarding its plutonium stockpile against theft by terrorists
Contribution of the passive properties of the rotator cuff to glenohumeral stability during anterior-posterior loading

Abstract The passive properties of the rotator cuff have been shown to provide some stability during anterior-posterior (AP) translation. However, the relative importance of the rotator cuff to joint stability remains unclear. The purpose of this study was to quantify the force contributions of the rotator cuff and of capsuloligamentous structures at the glenohumeral joint during AP loading. We hypothesized that the rotator cuff acts as a significant passive stabilizer of the glenohumeral joint and that its contribution to joint stability is comparable to the contribution made by the components of the glenohumeral capsule. A robotic/universal forcemoment sensor testing system was used to determine both the multiple “degrees of freedom” joint motion and the in situ force carried by each soft tissue structure during application of an 89N AP load at 4 abduction angles. The percent contribution of the rotator cuff to the resisting force of the intact joint during AP loading was significntly greater during posterior loading (35% ± 26%) than during anterior loading at 60° of abduction (P
Infrared spectra of matrix isolated and solid ethylene. Formation of ethylene dimers

Spectra of matrices with ethylene/argon ratios from 1/1 to 1/999 and a 1/24 ethylene/xenon matrix have been recorded in the temperature range 15–105 K. From relative i.r. intensities, frequency shifts and statistical calculations, the data are interpreted in terms of a monomer → dimer → aggregate → crystal scheme. It is proposed that the dimer, (C2H4)2, has D2d symmetry with a structure determined by quadruple hydrogen bonding and hydrogen-hydrogen repulsion. A method is described for calculation of the vibrational splitting due to interactions between the dimer molecular constituents. Solid ethylene has been studied between 15 and 85K. A transformation between two crystalline phases is characterized.
Gallstones in chronic spinal cord injury: is impaired gallbladder emptying a risk factor?

Abstract Objectives: To confirm that spinal cord injured persons are susceptible to gallstones and to evaluate the role of gallbladder stasis as a risk factor. Study Design: Twenty-nine subjects with chronic spinal cord injury underwent fasting ultrasonography to determine the incidence of gallstones and to quantitate gallbladder emptying response to a 20g fat liquid meal. Gallbladder emptying fraction was compared to that of healthy subjects studied concurrently. Results: Gallstones or sludge were found in 6 spinal cord injured men, a minimal prevalence of 21%. Four additional subjects had prior cholecystectomy for stones, giving a potential maximal prevalence of 30%. Four of the 6 subjects had gallstone risk factors of diabetes, obesity, and/or family history. Gallbladder stasis was not apparent in chronic spinal cord injured subjects. Only 5 subjects had poor gallbladder emptying, and 4 of them had diabetes and/or obesity. Conclusions: The study confirms an increased prevalence of gallstones after spinal cord injury. However, gallbladder stasis did not appear to be etiologic, and most gallstones were associated with conventional risk factors. The results do not support a general policy of gallstone screening or prophylactic therapy after spinal cord injury.
Problems related to the synthesis of 3-aziridinyl-6-chloropyridazine

The correct structure of the reported 3-aziridinyl-6-chloropyridazine was found to be 3-[β-(1-aziridinyl)ethylamino]-6-chloropyridazine, which was confirmed by n. m. r. studies. The relative ease of nucleophilic displacement of a methylsulfonyl group versus a chloro group in equivalent positions on a pyridazine or a pyrimidine ring was compared. It was observed that the chloro rather than the methylsulfonyl group was preferentially replaced, as illustrated by substitution studies of 3-chloro-6-methylsulfonylpyridazine and 4-chloro-6-methylsulfonylpyrimidine.
Optimal Selection of Acquisition Sources.

The problem addressed is that of optimally choosing the source from which to order a book. Each acquisition source is characterized by frequency distributions for discount and service time. A technique called decision analysis is used to determine the tradeoff between discount and service time most consistent with the librarian's preferences.
Technical change in the U.S. primary metals industry

Abstract A dual cost function embodying biased technical change is estimated for the postwar primary metals industry. The identifying restriction of constant rates of factor augmentation is used to derive significant estimates of rates of biased technical change which are consistent with the induced innovation hypothesis. Also, the bias in elasticity estimates which results from ignoring biased technical change is shown to be serious.
Platyamoeba stenopodia n. g., n. sp., a freshwater amoeba.

SYNOPSIS. Platyamoeba stenopodia n. g., n. sp., isolated from a lake in Alabama, is an amoeba with flattened form, usually more than 2.5 × as long as broad, the anterior half hyaline and the posterior half granular, with a single vesiculate nucleus at the posterior edge of the hyaline region. It forms a transitory floating stage with slender, hyaline pseudopods. Its cyst is spherical, uninucleate, with a smooth inner wall and a thinner, closely applied outer wall, which is often slightly wrinkled. Length of locomotive amoeba 15–36 μ diameter of cyst 7–11.5 μ Reproduction by binary fission with mesomitotic nuclear division, the nuclear membrane disappearing in prophase. The genus Platyamoeba is erected for amoebae including this organism; the type species is P. placida.
On the Use of Symmetry to Simplify the Constitutive Equations of Isotropic Materials with Memory

This paper is concerned with general, compressible, isotropic materials, solid or fluid, characterized by functionals which give the stress when the history of the strain is specified. It is shown that for certain broad classes of motions the requirements of material symmetry and frame-indifference greatly simplify the form of constitutive equations. These simplifications are derived without invoking integral expansions or other special hypotheses of smoothness for material response. Among the motions considered in detail are those which are locally equivalent to pure extensions and sheared extensions.
Laboratory measurements of sulfur dioxide deposition velocity on marble and dolomite stone surfaces

Abstract The deposition velocity of SO2 on marble and dolomite stone surfaces in a humid atmosphere was measured as a function of time in the laboratory using continuous monitoring techniques. The deposition velocity of SO2 on marble varied between 0.02 and 0.23 cm s−1, and was generally observed to decrease with time. The deposition velocity of SO2 on dolomite varied between 0.02 and 0.10 cm s−1, and gradually increased over the first 2000 ppm-h of exposure. For both types of stones, the deposition velocity increased significantly when condensed moisture was observed on the stone surface. Chemical analysis of the stone samples indicated that the SO2 deposited reacted with the stone materials to form gypsum (CaSO4·2H2O) on the marble surfaces and gypsum and epsomite (MgSO4·7H2O) on the dolomite surfaces.
Troponin Elevations After Electroconvulsive Therapy: The Need for Caution

Abstract Background Electroconvulsive therapy is used to treat patients with severe or resistant depression. Troponin elevations are associated with an adverse prognosis, and it is well known that central nervous system insults can cause biochemical evidence of cardiac injury. No study previously has studied this with electroconvulsive therapy. Methods Patients scheduled for electroconvulsive therapy were enrolled. Clinical information, an electrocardiogram, and a baseline sample for cardiac troponin I and T (cTnI and cTnT) were obtained. Electroconvulsive therapy was done with standard techniques. Subsequently, electrocardiograms and additional samples were obtained. cTnT was measured with the Roche assay and cTnI with the Dade Stratus equipment. Values above the 99th percentile were considered abnormal. Results Seventy patients completed the study. Four patients had elevated levels of cTn before treatment. In 3 patients, the elevations persisted. Four additional patients developed elevated cTn levels during electroconvulsive therapy. Two of the patients with cTn elevations died. No other events occurred during follow-up. Conclusions Elevations of cTn occurred in 11.5% of patients treated with electroconvulsive therapy. Some of the elevations preceded therapy and some occurred during treatment. Given the adverse prognostic importance of cTn elevations in general, in addition to additional studies, an increased degree of medical scrutiny may be appropriate for this group of patients and for those receiving electroconvulsive therapy. © 2011 Elsevier Inc. All rights reserved.
On the choice of functional form for hedonic price functions

The empirical results presented in this paper demonstrate the usefulness of quadriatic models in the estimation of hedonic price functions. We propose a quadriatic semi-log model, a restricted case of the quadriatic Box-Cox model, whose standardized marginal attribute prices are linear functions of the attribute vector. This specification outperforms the linear Box-Cox specification in terms of explanatory power, and captures much of the increase in explanatory power provided by the quadriatic Box-Cox model without the corresponding loss in the ability to interpret the coefficient estimates. For policy applications, the quadriatic Semi-log model provides a useful alternative to linear specification.
A Tale Of Dollars, Pediatrics, And Late-Night Calls About Infant Constipation

In accounting terms, nighttime phone help from a doctor was deemed to lose money. In human terms, it was priceless.
GENERAL CONNECTIONS BETWEEN INCLUSIVE AND EXCLUSIVE PROCESSES AND CLUSTER DECOMPOSITION.

General connections between exclusive and inclusive cross sections are studied by the generating-functional technique. Exclusive cross sections, inclusive cross sections, and correlation functions appear as coefficients of different Taylor series expansions of the same generating functional. Also studied are the connections between semi-inclusive processes where all charged particles in an event are observed and genuine inclusive processes with only some of the charged particles observed. No information on neutral particles enter in these connections for semi-inclusive processes. In special cases our results reproduce several seemingly unrelated aspects of inclusive processes treated by Mueller, Predazzi, and Veneziano and by Campbell and Chang. Our approach yields additional constraints and sum rules for inclusive cross sections. It is established that an infinite number of correlation functions are needed; and correlation in the pionization region necessarily exists if the multiplicity increases with energy and the transverse momenta of the final particles are limited. A brief comparison between exclusive and inclusive cluster decomposition is given. The question of diffraction dissociation is also very briefly discussed.
An Overview of System in Package (SiP) Applications and Technologies for CPU and Communications Systems

Research and development on System in Package (SiP) technologies is prevalent now both in industry and academia. This paper provides an overview of SiP from a CPU and communications systems perspective. Some of the items that will be covered include what defines a “system” for SiP, what value a SiP architecture brings, the types of SiP packaging architectures and technologies, and the challenges involved with developing SiP solutions.Copyright © 2005 by ASME
The normal pericardium

Abstract Under normal conditions the pericardium, with its fluid, lubricates the moving surfaces of the heart, holds the heart in a fixed geometric position and isolates the heart from other structures in the thorax, thus preventing adhesions and spread of infection. It also serves the following functions: (1) prevents dilatation of the heart chambers and insures that the level of transmural cardiac pressures will be low, never exceeding a few mm Hg; (2) prevents hypertrophy of the heart under conditions of strenuous exercise; (3) limits right ventricular stroke work under conditions of increased left ventricular outflow resistance; (4) prevents ventriculo-atrial regurgitation under conditions of increased ventricular end-diastolic pressures; (5) in association with the lungs and tissue surrounding the pericardium it facilitates the filling of the atria by the development of negative pericardial pressure during ventricular systole; (6) responds to nerve stimulation and reflexly affects blood pressure and heart rate; and (7) in association with the pleural fluid constitutes a hydrostatic system that automatically applies compensating hydrostatic pressures on the outside of the heart when gravitational or inertial forces acting on the heart are altered (during acceleration, for example). This automatic hydrostatic compensation insures that end-diastolic transmural pressure is the same at all hydrostatic levels of the ventricle; as a result the stretch of the muscle fibers is uniform, and the Frank-Starling mechanism operates equally at all hydrostatic levels within the ventricles.
Addressing Language Barriers: Building Response Capacity for a Changing Nation

The absence of universally available language services is a national healthcare system failure, the burden of which is suffered by patients with limited English proficiency and their healthcare providers. Conceptualizing mandatory provision of language access as an unfair, unfunded mandate ignores massive and fundamental social changes taking place. Overcoming language barriers is essential to safe, quality health care. This paper, informed by the experience of Hablamos Juntos, a national demonstration project funded by the Robert Wood Johnson Foundation, argues that national and health industry investments are needed to develop population-based approaches supported by communication and information technology, and that these investments may prove useful to improving healthcare communication for English-speaking patients as well.
Immunocytochemical evidence that quisqualate is selectively internalized into a subset of hippocampal neurons.

Abstract Quisqualic acid (QUIS) has been shown to interact with several glutamate receptor subtypes and uptake sites. We have previously demonstrated that a brief exposure of hippocampal cells to QUIS sensitizes them to depolarization by the α-amino-ω-phosphonate analogues of glutamate, AP4, AP5, and AP6. This QUIS-induced sensitization is accompanied by the active uptake of QUIS into hippocampal slices. In order to localize the sites of QUIS uptake into rat hippocampal slices, a polyclonal antibody against QUIS was raised in rabbits. Utilizing immunocytochemical techniques, we have identified immunoreactive axons and dendrites after brief exposure times to QUIS, and perikarya after longer exposure times to QUIS. The intensity of the QUIS immunoreactivity increased as the exposure time to QUIS increased. QUIS immunoreactivity was primarily found in stratum oriens and stratum radiatum, of regions CA1, CA2, and CA3 of the hippocampus as well as in the hilus and molecular layer of the dentate gyrus. The distribution and morphology of QUIS immunoreactive cells appeared to be similar to those of GABAergic interneurons. Glial fibrillary acidic protein (GFAP) did not co-localize with the QUIS-internalizing cells suggesting that they are not glia. Ultrastructural analysis revealed QUIS immunoreactive profiles within the stratum radiatum. Immunostained profiles at both the light and EM levels appeared, in many cases, to be swollen and showed signs of degeneration. Such changes were only evident in tissue exposed to QUIS. These data demonstrate that QUIS is taken up by a select group of neurons in the rat hippocampus.
Pelleted Beet Pulp Substituted for High-Moisture Corn: 3. Effects on Ruminal Fermentation, pH, and Microbial Protein Efficiency in Lactating Dairy Cows

The effects of increasing concentrations of dried, pelleted beet pulp substituted for high-moisture corn on ruminal fermentation, pH, and microbial efficiency were evaluated using eight ruminally and duodenally cannulated multiparous Holstein cows in a duplicated 4 x 4 Latin square design with 21-d periods. Cows were 79 +/- 17 (mean +/- SD) DIM at the beginning of the experiment. Experimental diets with 40% forage (corn silage and alfalfa silage) and 60% concentrate contained 0, 6.1, 12.1, or 24.3% beet pulp substituted for high-moisture corn on a DM basis. Diet concentrations of NDF and starch were 24.3 and 34.6% (0% beet pulp), 26.2 and 30.5% (6% beet pulp), 28.0, and 26.5% (12% beet pulp), and 31.6 and 18.4% (24% beet pulp), respectively. Substituting beet pulp for corn did not affect daily mean or minimum ruminal pH but tended to reduce pH range. Ruminal acetate:propionate responded in a positive exponential relationship to added beet pulp. Rate of valerate absorption from the rumen was not affected by treatment. Substituting beet pulp for corn up to 24% of diet DM did not affect efficiency of ruminal microbial protein production, expressed as microbial N flow to the duodenum as a percentage of OM truly digested in the rumen. Microbial efficiency was not correlated to mean pH or daily minimum pH. While microbial efficiency was not directly related to concentration of beet pulp fed, it was positively correlated with passage rate of particulate matter, as represented by starch and indigestible NDF, probably due to reduced turnover of microbial protein in the rumen.
Total Synthesis of 5-N-Acetylardeemin and Amauromine: Practical Routes to Potential MDR Reversal Agents

The total synthesis of the title compounds has been accomplished. The key step involves the kinetic stereoselective conversion of 19 → 20. The synthesis of 20 represents for the first time a direct method for constructing exo-pyrroloindoles from protected tryptophans in a highly diastereoselective manner. This step was followed by reverse prenylation (see conversion of 20 → 27). Using the methodology worked out for the titled compounds, a practical synthesis of several promising MDR reversal agents was possible. Biological data that provided the basis for selection of candidates for advanced study are presented. Preliminary profiling of the zones of the molecules that are responsive to changes while still retaining MDR reversal ability are described. On the basis of these findings, compounds 2, 50, and 51 were selected for more extensive biological follow-up.
Higher order impedance boundary conditions applied to scattering by coated bodies of revolution

In this paper higher order impedance boundary conditions will be employed in the solution of scattering by coated conducting bodies of revolution. The higher order impedance solution reduces the total number of unknowns relative to the exact solution, and produces a system matrix which is less dense than that of the exact solution. The construction of the solution involves two distinct steps. In the first step the body of revolution is replaced by an equivalent set of electric and magnetic currents on its exterior surface which generate the true fields outside the body. An integral equation relating these currents through the free space Green's function is derived. Step two employs the higher order impedance boundary condition to relate the electric and magnetic currents on the surface of the body. This replaces the rigorous solution of the interior problem. The higher order impedance boundary conditions are derived by obtaining an exact impedance boundary condition in the spectral domain for the coated ground plane, approximating the impedances as ratios of polynomials in the transform variables, and employing the Fourier transform. The resulting spatial domain differential equations are solved in conjunction with the integral equation using the method of moments. Several examples of bistatic and monostatic radar cross section for coated bodies of revolution are used to illustrate the accuracy of the higher order impedance boundary condition solution relative to the standard impedance boundary condition solution and the exact solution. The effects of coating thickness, loss, and curvature on the accuracy of the solution are discussed. >
Semi-Automatic Gas-Less Process for Girth Welding X-80 Line Pipe

A new process (M2M™) to girth weld API Grade X-80 line pipe with a gas-less technology is presented. This process combines innovations in controlling arc length and energy input with microstructure control of the weld metal deposited to achieve high strength (over matching 550 MPa yield strength) and Charpy V-Notch toughness of over 60 Joules at −20°C. This paper will concentrate on the metallurgical aspects of the weld metal and the systematic steps taken to achieve high strength weld metal without sacrificing toughness. The development of an appropriate slag system to achieve the best possible microstructure for high toughness weld metal is discussed. The indirect effects of the slag system on the weld metal composition, which in turn affects the microstructure and physical properties, are detailed. In order to achieve sound weld metal without gas protection using a semi-automatic process, a basic slag system with minimal acidic components is used to improve the cleanliness of the weld metal without sacrificing weldability. In addition, a complex combination of micro-alloying elements is used to achieve the optimum precipitation sequence of nitrides that is critical for high toughness. The final part of this paper gives details about the robustness of this process to weld high strength pipe. The results show that this is a practical and unique solution for girth welding of X-80 pipe to achieve acceptable toughness and over a 15% overmatch in yield strength of X-80 pipe without sacrificing productivity.© 2006 ASME
Discussion of “Pedological relations of infiltration phenomena”

Smith provides an illuminating consideration of infiltration through soil in relation to the structure and texture of the soil its moisture content, and the variation of infiltration for A, B, and C soil zones. The organic nature of soil might also be stressed. Rotting rootlets provide passageways for water in addition to physical structure and texture. The impression is gained that mechanical treatment, such as plowing and harrowing, general decreases the infiltration capacity of soil, through destruction of surface structure, and fragmentation. This appears true of the soil in the physical sense. Equally true, in a plowed soil, may be the formation of puddling colloids after a rain, through the breaking of natural granules into fragments. However, the surface infiltration is increased by plowing and harrowing through the turnover of the sod layer composed of grasses and weeds. Smith does not consider the sod layer as a soil zone, yet it is the first barrier that precipitation must pass before it enters the structural crevices and textural pores of the soil. Although a dense sod layer usually does not increase runoff because of its retentive nature, it increases interception, and hence evaporation, so unless the sod is economic, the water is lost anyway.
Advising in Undergraduate Honors Programs: A Learner-Centered Approach

Findings from a study of undergraduate honors education introduce a new perspective into the debate over approaches to academic advising. Learner-centered advising emerged as a key attribute of high-quality honors programs. The learner-centered approach is consistent with a range of advising approaches and styles because through it advisors retain emphasis on student-learning experiences and development. Insights on existing advising perspectives and recommendations for advising honors students are discussed. Advisors and administrators are encouraged to examine both practice and underlying philosophy while conducting further research to develop advising theory that will inform effective practice.
Restriction fragment variation in the nuclear and chloroplast genomes of cultivated and wild Sorghum bicolor

Fifty-six accessions of cultivated and wild sorghum were surveyed for genetic diversity using 50 low-copy-number nuclear DNA sequence probes to detect restriction fragment length polymorphisms (RFLPs). These probes revealed greater genetic diversity in wild sorghum than in cultivated sorghum, including a larger number of alleles per locus and a greater portion of polymorphic loci in wild sorghum. In comparison to previously published isozyme analyses of the same accessions, RFLP analysis reveals a greater number of alleles per locus. Furthermore, many RFLP alleles have frequencies between 0.25–0.75, while the vast majority of isozyme alleles are either rare ( 0.75). Correlations between genetic and geographic distances among the accessions were stronger when calculated with RFLP than with isozyme data. Systematic relationships revealed by nuclear and chloroplast restriction site analysis indicate that cultivated sorghum is derived from the wild ssp. arundinaceum. The portion of the wild gene pool most genetically similar to the cultivars is from central-northeastern Africa. Previous published data also suggested that this is most likely the principal area of domestication of sorghum. Introgression between wild and cultivated sorghum was inferred from disconcordant relationships shown by nuclear and chloroplast DNA markers. Introgression apparently occurs infrequently enough that the crop and its wild relatives maintain distinct genetic constitutions.
Imidazole-containing amino acids as selective inhibitors of nitric oxide synthases

Two series of imidazole-containing amino acids (1a-e and 2a-c), all larger homologues and analogues of L-histidine, were prepared. Since imidazole and phenyl substituted imidazoles have been reported to be inhibitors of NOS and the mode of action of these compounds as heme ligands is a potential mechanism of inhibitory action, we designed imidazole-containing amino acids as combined inhibitors at both the amino acid as well as heme binding sites. To study the influence of the distance between the amino acid moiety and the imidazole moiety on inhibitory potency, the number of carbons between these two functional groups was varied from two to six. The structure-activity relationships of this class of inhibitors can be correlated with the distance between the heme and the amino acid binding sites of the enzyme. Two of the compounds (1b and 1d) with three and five methylenes between the imidazole and amino acid functional groups, respectively, were found to be potent and selective inhibitors for nNOS and iNOS over eNOS. When phenyl was substituted on the nitrogen of the imidazole, both the potency and isoform selectivity diminished.
Response of an elastically non-linear system to transient disturbances

Abstract Tje problem relates to an undamped, elastically non-linear, single-degree-of-freedom system subjected to three forms of ground motion pulses (rectangular, cosine and “skewed” cosine); each form consists of a single pulse, the duration of which has been varied over a wide range. The maximum relative displacements (maximum distortions) have been plotted in dimensionless form as functions of the pulse durations. Under some circumstances the non-linearity results in reduced maximum distortion, but in other cases it acts to increase it. Simple quantitative conclusions cannot be drawn.Analytical, graphical and experimental methods were employed; the graphical method has been presented in detail.
Two-fluid oscillatory flow in a channel

Abstract The validity of Navier's partial slip condition is investigated by studying the oscillatory flow in a coated channel. The two-fluid model is used to solve the unsteady viscous equations exactly. Partial slip is experienced by the core fluid. It is found that Naviers condition does not hold for an unsteady core fluid.
The influence of boron segregation on the structure and mechanical properties of boundaries in bicrystals of Ni3Al

This paper reports that in contrast to the high ductilities reported for single crystals of ordered ({gamma}) Ni{sub 3}Al, the ductility in polycrystalline form is extremely limited. The discovery by Aoki and Izumi that microalloying with boron greatly increases the ductility of polycrystalline Ni{sub 3}Al has initiated spirited scientific investigation into the structure and properties of grain boundaries in this material. One consequence of the addition of boron could be an increase in the cohesive properties of the grain boundaries. However, at present the most widely accepted explanation for the improved ductility of the grain boundaries is the boron cause compositional disordering of the grain boundary region. As first suggested by King and Yoo, the total number of possible dislocation reactions is generally much larger at a grain boundary in disordered ({gamma}) material (the FCC structure) than in the ordered Ll{sub 2} phase. consequently, for the disordered case, the absorption or transmission of dislocations across the boundary should be easier, large stress concentrations should not develop as readily at the boundary, and the propensity for intergranular fracture should be reduced.
1027 Rapid and accurate free-breathing 3D delayed enhancement imaging for myocardial viability assessment: comparison with breath-hold 2D imaging

Introduction Delayed enhancement MRI (DE-MRI) has been established as a diagnostic imaging standard for myocardial viability assessment. The current reference standard for DE-MRI uses an inversion-recovery 2D gradient echo sequence to acquire images during repetitive breathholds. This breath-hold 2D (2DBH) technique requires significant patient cooperation and suffers from potential slice misregistration due to diaphragmatic excursions in different breath-holds. To overcome these limitations, navigator-gated 3D (3DNAV) DE-MRI has been developed using a diaphragmatic navigator to monitor respiratory motion and adjust data acquisition accordingly. Previous 3DNAV sequences employed the accept/reject gating algorithm with a fixed gating window which can lead to long imaging time in the case of a steady diaphragmatic drift.
Ross Ashby's general theory of adaptive systems

In the 1950s and 1960s Ross Ashby created a general theory of adaptive systems. His work is well known among cyberneticians and systems scientists, but not in other fields. This is somewhat surprising, because his theories are more general versions of the theories in many fields. The philosophy of science claims that more general theories are preferred because a small number of propositions can explain many phenomena. Why, then, are Ashby's theories not widely known and praised? Do scientists really strive for more general, parsimonious theories? This paper reviews the content of Ashby's theories, discusses what they reveal about how scientists work, and suggests what their role might be in the academic community in the future.
Chronic adrenaline treatment fails to down-regulate the Del301–303-α2B-adrenoceptor in neuronal cells

BACKGROUND AND PURPOSE A polymorphism of the human alpha(2B)-adrenoceptor (Del(301-303)-alpha(2B)-adrenoceptor) has been described, and this receptor exhibits reduced G-protein-coupled receptor kinase (GRK) phosphorylation and impaired short-term desensitization. Expression of the Del(301-303)-alpha(2B)-adrenoceptor also is associated with an increased risk for myocardial infarction in humans. Recent evidence from our laboratory suggests a quantitative relationship between cellular GRK3 expression levels and the sensitivity of the alpha(2B)-adrenoceptor to agonist-induced down-regulation. Therefore, the present study was undertaken to study agonist-induced down-regulation of the wild-type (WT)- and Del(301-303)-alpha(2B)-adrenoceptor in a neuronal cell model. EXPERIMENTAL APPROACH Haemagglutinin (HA) epitope-tagged WT- and Del(301-303)-alpha(2B)-adrenoceptor containing plasmids were constructed and the receptors were stably or transiently transfected in neuroblastoma/glioma hybrid NG108 cells. The expression levels in stable transfects were approximately 50 fmol x mg(-1). These cells were used to examine agonist-induced down-regulation and phosphorylation of the WT- and Del(301-303)-alpha(2B)-adrenoceptor. KEY RESULTS The Del(301-303)-alpha(2B)-adrenoceptor, compared with the WT-alpha(2B-)adrenoceptor, displayed reduced adrenaline-stimulated (20 microM) phosphorylation and did not down-regulate in response to adrenaline (20-1000 microM). Using immunofluorescence labelling, we observed that transiently transfected WT-alpha(2B)-adrenoceptors internalized upon adrenaline treatment whereas the Del(301-303)-alpha(2B)-adrenoceptor did not. Finally, we determined the effect of adrenaline on the Del(301-303)-alpha(2B)-adrenoceptor in cells stably over-expressing GRK3 3-fold. In spite of the GRK3 over-expression, 20-1000 microM ADR failed to down-regulate or to increase phosphorylation of the Del(301-303)-alpha(2B)-adrenoceptor in these cells. CONCLUSIONS AND IMPLICATIONS The results suggest that the 301-303 deletion mutation of the alpha(2B)-adrenoceptor eliminates agonist-induced down-regulation, an effect that cannot be overcome by increasing agonist concentration or by modest GRK3 over-expression.
Comparing Fear of Positive Evaluation to Fear of Negative Evaluation in Predicting Anxiety from a Social Challenge

This study compared FNE and FPE scales in predicting anxious responding to a social challenge. 101 undergraduate participants completed a social manipulation requiring them to deliver a 3 minute videotaped speech they believed would be rated by faculty judges. Participants then received bogus positive, negative, or no feedback and were informed they were selected to present their speech directly to the panel of judges. FNE was the strongest predictor of state anxiety following the initial speech task, while FNE and FPE predicted somatic response to this task. Regardless of feedback type, FPE was a significant predictor of anxiety during the second speech task. Results are consistent with an overall cognitive model of social anxiety and suggest that FPE and FNE are distinct predictors of anxiety the under specific conditions.
A Shooting Approach to Chaos in the Lorenz Equations

Abstract We prove that under certain conditions, the Lorenz equations support a form of chaos. The conditions have been verified for a particular set of parameter values, showing that there is a natural 1:1 correspondence between a set of solutions and the set of all sequences on countably many symbols. The computing required was modest.
Health-related quality of life in breast cancer survivors of different sexual orientations

Purpose Sexual minority women, e.g., lesbians and bisexuals, are an underserved population but not much is known about their quality of life (QOL) after a breast cancer diagnosis. For this reason, this study examines the physical and mental QOL and its association with sexual orientation in a cohort of long-term nonrecurring breast cancer survivors.
The Caravan Trade of the Sahara

(1917). The Caravan Trade of the Sahara. Journal of Geography: Vol. 15, No. 7, pp. 221-226.
Exploration of the correlation between autism spectrum disorder symptomology and tantrum behaviors

Abstract The purpose of the current study was to investigate the relationship between the presence of Autism Spectrum Disorder (ASD) symptoms and tantrum behaviors in 598 children ranging in age from two to sixteen years old who meet cutoffs for ASD. Diagnostic categories created in the current study were provided by the Autism Spectrum Disorder – Diagnostic Child Version (ASD-DC). Initial analysis replicated previous research revealing significant differences in the expression of tantrum behavior between the ASD, Atypical, and Normal groups. Pearson Bivariate correlations were then computed for each individual's ASD symptom score and their total score on the Tantrum behavior subscale. Follow-up correlations found significant positive correlations between individual's in the Atypical, Normal, and ASD categories and their scores for the Tantrum behavior subscale of the Autism Spectrum Disorders – Comorbidity for Children (ASD-CC). Post hoc analyses revealed that the correlation between ASD symptomology and tantrum behaviors in the Normal group was significantly different when compared to children in the ASD group.
WLC23-5: Digital Multi-Carrier Differential Signaling for UWB Radios

In this paper, we introduce a novel differential signaling approach for ultra-wideband (UWB) communications using multiple digital carriers. Unlike the transmitted reference (TR), differential and noncoherent UWB that also bypass explicit channel estimation, our scheme avoids the analog delay element whose on-chip implementation is challenging. Compared with the frequency-shifted reference (FSR) UWB, our multi-carrier differential signaling captures the signal energy more effectively and can achieve the full diversity gain, even in the presence of inter-frame interference. In addition, our approach relies on digital carriers that do not incur any spectrum expansion and can be realized with standard discrete-cosine transform (DCT) or fast Fourier transform (FFT) circuits operating at the frame-rate. Simulations are also carried out to corroborate our theoretical analysis.
The effects of residual stress on the mechanical properties of glassy polymers

Residual stresses can have either beneficial or detrimental effects on the mechanical properties of plastics. Manufacturing processes frequently impose residual stresses on plastics. In this study, controlled thermal processes were used to impose surface compressive stresses on polycarbonate beam samples (6.4 by 12.5 by 80 mm). Resistance strain gage and photoelastic techniques were developed to measure the magnitude of these stored stresses. The compressive surface stresses were found to be between 14 MPa (2000 psi) and 31 MPa (4500 psi) and to vary with process method and cooling rate. The mean fatigue life (in bending) of the treated beam samples was found to improve by a factor of 10 over that of untreated samples. The increase in the fatigue life of the treated samples appears to be directly related to the magnitude of the surface compressive residual stress in the samples. The imposed residual stress, as determined by photoelastic measurements, has not appreciably relaxed after 1 year of storage at room temperature.
Molecular cloning and characterization of the human xanthine dehydrogenase gene (XDH)

Abstract Xanthine dehydrogenase (XDH, EC 1.1.1.204) is a rate-limiting enzyme in the oxidative metabolism of purines and is thought to play a key role in a variety of pathophysiologic processes including ischemia/reperfusion injury, viral pneumonia, and renal failure. We herein report the isolation and characterization of the human XDH gene. The gene is composed of 36 exons and 35 introns and spans at least 60 kb. The exon sizes range from 53 to 279 bp, and the intron sizes range from 0.2 to over 8 kb. Using primer extension and RNase protection analyses, two transcriptional initiation sites were identified 59 and 82 nucleotides upstream of the ATG start codon. One Goldberg–Hogness box (ATTTAT)-like sequence was found 24 bp upstream from the second transcriptional initiation site, and two inverted CCAAT sequences were found 19 and 42 bp upstream from the second transcriptional initiation sites. A relative GC-enriched region was found between −55 and −121. Approximately 2 kb of the 5′-flanking region was sequenced, and a variety of putative regulatory elements were identified including C/EBP binding sites, IL-6 and NF-κB sites, and potential TNF-RE, IFN-γ-RE, and IL-1-RE sites.
Lipoproteins, Cholesterol and Serum Proteins as Predictors of Myocardial Infarction

The normal variability of lipoprotein and cholesterol levels was established for 6 women over a period of 5 months for comparison with levels in people who develop myocardial infarction. We have studied 107 normal men for 7 years. Among these 11 developed infarction and 6 angina pectoris. Little change in lipid levels was associated with these events. Electrophoretic patterns early after infarction showed certain relatively characteristic changes, especially increase in α-2 and β globulins and fibrinogen. Low-density lipoprotein also increased. While α-2 globulin was usually greatest in patients with the most extensive myocardial damage, there was little over-all correlation between lipoprotein pattern and severity of infarction. The "coronary profile" can be more sharply delineated by repeated lipid measurements because as a group those with atherosclerosis and infarction exhibit slightly elevated values.