cssi/SciSciGPT-SciSciNet huggingface dataset:
Inhibition of Sindbis virus replication in Aedes albopictus cells deprived of methionine.

Abstract When Sindbis virus-infected Aedes albopictus cells were incubated in medium containing all amino acids except methionine, there was no yield of infectious virus. Neither was viral RNA synthesized. The omission of other amino acids had either no effect or a much lesser effect than the omission of methionine. However, when all amino acids were removed, or if methionine was the only amino acid present, the virus yields were close to normal. Cycloleucine, a compound which inhibits the synthesis of S -adenosyl methionine also inhibited Sindbis virus replication and the synthesis of viral RNA. Methionine-starved chick embryo fibroblasts or BHK cells made normal amounts of virus.
Comments on the literature of the humin fraction of humus

Abstract An extensive and critical review of the literature on the humin fraction of humus has demonstrated two patterns of usage of the term which are in conflict with its generally accepted definition. In the first instance, the word humin was widely used to refer to the alkali-soluble products of the hydrolysis of amino acids and/or sugars. In the second instance, what are apparently incorrect translations of German words such as Huminsubstanzen have caused papers describing the humic materials considered collectively to be indexed under the keyword humin in early volumes of Chemical Abstracts. Consequently, 66 of the 201 papers indexed under the keyword humin in Chemical Abstracts, from volume 1 through volume 77 (1972) do not refer to humin as it is usually defined.
SYNAPTOSOMAL PHOSPHORYLATION OF D-GLUCOSAMINE

— Synaptosomal fractions from rat brains can phosphorylate d-glucosamine once it is transported across the synaptosomal membrane. Intrasynaptosomal phosphorylation of d-glucosamine was rapid; up to 80% of the d-glucosamine was recovered as the phosphorylated amino sugar during 15 min of incubation with the substrate. Transport of d-glucosamine was the rate-limiting step in the uptake process since in the presence of cytochalasin B, a specific sugar transport inhibitor, the uptake of d-glucosamine was inhibited to the same extent as its phosphorylation. The pH optimum for phosphorylation of d-glucosamine by lysed synaptosomal preparations was between 7.5 and 9.0. The mean Km and Vmax values for this phosphorylation were 0.46 DIM and 676 nmol/mg protein per min, respectively. Phosphorylation of d-glucosamine was inhibited competitively by d-glucose, 2-deoxy-d-glucose and N-acetyl-d-glucosamine and uncompetitively by d-glucose-6-phosphate. The phosphorylation was strongly inhibited by several sulfhydryl reagents, but was insensitive to product inhibition, cytochalasin B, phloretin and phloridzin.
Thyrotropin and prolactin response to thyrotropin-releasing hormone in depressed and nondepressed alcoholic men.

Abstract Thyrotropin-releasing hormone (TRH) stimulation tests were performed on 81 alcoholic men after at least 3 weeks of abstinence. Subjects were given 500 μg of TRH intravenously, and thyroid-stimulating hormone (TSH) and prolactin (PRL) were measured at baseline, and then 15 and 30 min later. Comparisons were made among alcoholics with ( n = 27) and without ( n = 54) a lifetime history of depression as determined by the Diagnostic Interview Schedule. Nine nondepressed, nonalcoholic subjects served as controls. Alcoholics with or without a depression history did not differ from each other or from controls in TSH or PRL response area under the curve. Blunted TSH responses were present in 10 (12%) of the alcoholics and none of the controls when blunting was defined as a Δmax TSH μU / ml . When blunting was defined as a Δmax TSH μU / ml , 18 (22%) of the alcoholics and 1 (1%) of the controls were blunted. Conversely, 2 (2.5%) of the alcoholics had a Δmax TSH > 32 μU / ml . All subjects were clinically euthyroid. Contrary to expectation, depressed subjects were slightly less likely to show blunted responses than nondepressed subjects. No relationship was found between neuroendocrine measurements and several measurements of alcoholism or depression. Some alcoholic subjects show a blunted TSH response to TRH injection, which may be a function primarily of the alcoholism itself. The precise mechanism remains unknown.
On the maintenance of UI-integrated mashup applications

This paper describes the maintenance of long-lived mashup applications that are integrated at the user interface (UI) layer. It presents techniques that help mashup developers to maintain applications by identifying when and how the original applications' UIs change. It describes a novel mashup editing environment that can be used to create, share, and edit mashups. This paper also presents an experiment that demonstrates our approach's ability to track UI changes as an application evolves and a demonstration of the effort expanded by developers to maintain mashups as the applications used by the mashups evolve.
An examination of the factors contributing to microcomputer technology acceptance

Abstract This paper examines the factors that explain variations in microcomputer acceptance. Results of this study identify two main factors contributing to microcomputer acceptance: behavioral beliefs and normative beliefs. We found that individuals use microcomputers if they believe that (a) using the system will increase their performance and productivity, and (b) if they feel social pressure to use microcomputers, mainly pressure from individuals or groups with whom they are motivated to comply think they should use them. We also found that perceived usefulness and computer anxiety had strong direct effects on attitudes and that both computer anxiety and perceived usefulness mediated the effects of the external factors (computer skills and organizational support) on microcomputer usage. Subjective norms also had a direct effect on microcomputer usage and mediated the effect of normative beleifs on microcomputer usage. Finally, results also show that organizational usage (peer usage, management usage, and subordinate usage) and organizational support (management and information center support) had direct effects on normative beliefs. Implications for practitioners and researchers are offered on user acceptance of microcomputer technology. We also provided some design and implementation guidelines that foster computer technology acceptance.
TPP1 is a homologue of ciliate TEBP-β and interacts with POT1 to recruit telomerase

Telomere dysfunction may result in chromosomal abnormalities, DNA damage responses, and even cancer. Early studies in lower organisms have helped to establish the crucial role of telomerase and telomeric proteins in maintaining telomere length and protecting telomere ends. In Oxytricha nova, telomere G-overhangs are protected by the TEBP-alpha/beta heterodimer. Human telomeres contain duplex telomeric repeats with 3' single-stranded G-overhangs, and may fold into a t-loop structure that helps to shield them from being recognized as DNA breaks. Additionally, the TEBP-alpha homologue, POT1, which binds telomeric single-stranded DNA (ssDNA), associates with multiple telomeric proteins (for example, TPP1, TIN2, TRF1, TRF2 and RAP1) to form the six-protein telosome/shelterin and other subcomplexes. These telomeric protein complexes in turn interact with diverse pathways to form the telomere interactome for telomere maintenance. However, the mechanisms by which the POT1-containing telosome communicates with telomerase to regulate telomeres remain to be elucidated. Here we demonstrate that TPP1 is a putative mammalian homologue of TEBP-beta and contains a predicted amino-terminal oligonucleotide/oligosaccharide binding (OB) fold. TPP1-POT1 association enhanced POT1 affinity for telomeric ssDNA. In addition, the TPP1 OB fold, as well as POT1-TPP1 binding, seemed critical for POT1-mediated telomere-length control and telomere-end protection in human cells. Disruption of POT1-TPP1 interaction by dominant negative TPP1 expression or RNA interference (RNAi) resulted in telomere-length alteration and DNA damage responses. Furthermore, we offer evidence that TPP1 associates with the telomerase in a TPP1-OB-fold-dependent manner, providing a physical link between telomerase and the telosome/shelterin complex. Our findings highlight the critical role of TPP1 in telomere maintenance, and support a yin-yang model in which TPP1 and POT1 function as a unit to protect human telomeres, by both positively and negatively regulating telomerase access to telomere DNA.
Cataloging digital geographic data in the information infrastructure: a literature and technology review

Abstract Advances in computer and telecommunications technology have brought on a new era in the Information Age resulting both in the proliferation of digital geographic data and the emergence of an information infrastructure to facilitate the transfer of electronic information. We need to plan for the integration of digital geographic data into the information infrastructure. Those using the information infrastructure will require guides to access the information contained therein efficiently and effectively. Cataloging has long been recognized as an efficient method for condensing knowledge of large collections of items. Special approaches have proven successful for many applications, including digital geographic data. The advent of interconnecting catalogs to create vast virtual libraries of information leads to a need to overcome differences in special systems yet still allow users to access many of the special features found in individual systems. This article looks at the background of various cataloging approaches, at the needs of digital geographic data users, at trends in automated cataloging, and at trends in organizing resources in an electronic network environment.
Guidelines for differential diagnoses in a population with posttraumatic stress disorder.

In a large posttraumatic stress disorder (PTSD) and depression treatment outcome study, thorough diagnostic assessments of veterans at pretreatment, posttreatment, and 3 follow-up times were completed. The research team that reviewed these assessments encountered several challenges in the differential diagnosis of PTSD because of high comorbidity and symptoms shared with or resembling other disorders. For example, how do mental health professionals distinguish symptoms of agoraphobia from avoidance and hypervigilance symptoms of PTSD? When are hallucinations symptomatic of PTSD (e.g., flashbacks) versus a nonpsychotic near-death experience or an independent psychotic disorder? How do mental health professionals differentiate overlapping symptoms of PTSD and depressive disorders? To help make reliable diagnoses, the team developed clarifying questions and diagnostic guidelines, which may prove useful to other clinicians and researchers working with PTSD populations.
Notes: A characterization of multivariate normality through univariate projections

This paper introduces a new characterization of multivariate normality of a random vector based on univariate normality of linear combinations of its components.
Triply periodical particulate matrix compositesinvarying external stress fields

Abstract We consider a linear elastic composite medium, which consists of ahomogeneousmatrix containing aligned ellipsoidal uncoated or coated inclusions arranged in aperiodic arrayand subjected to inhomogeneous boundary conditions. The hypothesis of effectivefieldhomogeneity near the inclusions is used. The general integral equation obtained reducestheanalysis of infinite number of inclusion problems to the analysis of a finite number of inclusionsinsome representative volume element (RVE) . The integral equation is solved by theFouriertransform method as well as by the iteration method of the Neumann series ( first-orderapproximation) . The nonlocal macroscopic constitutive equation relating the unit cellaverages ofstress and strain is derived in explicit closed forms either of a differential equation ofasecond-order or of an integral equation. The employed of explicit relations fornumericalestimations of tensors describing the local and nonlocal effective elastic properties aswell asaverage stresses in the composites containing simple cubic lattices of rigid inclusions andvoids areconsidered.
Cardiac Paraganglioma Presenting With Acute Myocardial Infarction and Stroke

We report an unusual presentation of cardiac paraganglioma with acute myocardial infarction and stroke induced by exercise and review the literature regarding this rare cardiac tumor.
Waxy Soft White Wheat: Extrusion Characteristics and Thermal and Rheological Properties

Waxy wheat flour was analyzed for its thermal and rheological properties and was extruded to evaluate its potential for extruded products. Normal soft white wheat flour was analyzed with the same methods and same extrusion conditions to directly compare differences between the two types of flour. Through DSC analysis, waxy wheat flour was found to have a higher gelatinization peak temperature of 66.4°C than normal wheat at 64.0°C, although the transition required 2.00 J/g less energy. Rapid visco-analysis indicated that the waxy wheat flour pasted much more quickly and at lower temperatures than the normal wheat flour. Preliminary extrusion experiments were conducted to determine the optimal screw profile for waxy wheat with respect to maximum radial expansion. The optimum screw profile was used for extrusion trials with varying flour moisture (15–25% wb) and extruder screw speed (200–400 rpm) while monitoring process conditions including back pressure and specific mechanical energy. Physical properties o...
Dermoscopy: alternative melanocytic algorithms-the ABCD rule of dermatoscopy, Menzies scoring method, and 7-point checklist.

In the year 2000, the Second Consensus Meeting on Dermoscopy was held over the Internet. Experts from around the world were asked to evaluate melanocytic, nonmelanocytic, benign, and malignant skin lesions using pattern analysis, the ABCD rule of dermatoscopy, Menzies scoring method, and the 7-point checklist. One hundred twenty-eight digital dermoscopic images were randomly subdivided into a training set of 20 images in which the unifying concepts of pattern analysis, the ABCD rule of dermatoscopy, Menzies scoring method, and the 7-point check list were presented. Those melanocytic algorithms were then used to evaluate another 108 cases. The results of the Second Consensus Meeting were presented at the First World Congress of Dermoscopy held in Rome, Italy, March 2001 and in an atlas that outlined the results and illustrated all of the cases.1,2 One of the main conclusions from the Second Consensus Meeting was that the four melanocytic algorithms studied were all valid ways to evaluate pigmented skin lesions with dermoscopy. This article will present the unifying concepts of the ABCD rule of dermatoscopy, Menzies scoring method, and the 7-point checklist. Other less-well-known and studied dermoscopic algorithms will not be presented.3–5
Gray Crescent in the Optic Nerve Head

Twenty-nine patients had a slate-gray crescent within the peripheral tissue of the optic nerve head. Twenty-five of the patients were black; an examination of 100 consecutive black patients revealed the gray crescent in 12 cases. The gray crescents were usually bilateral and were most often located along the temporal or inferotemporal disk margin. Failure to recognize the anatomic location of the gray crescent may lead to misdiagnosis of disk cupping.
Design and Testing of a Piezoelectrically Driven Airspike System on a .40 Cal Supersonic Projectile

This paper investigates the feasibility of using a piezoelectrically driven airspike system as a method of flight control on .40 caliber supersonic projectiles. The paper begins with a description of airspikes and a summary of their history in missiles and munitions. The paper then describes the piezoelectric actuation system and models its unloaded characteristics using bending beam theory. When the airspike is deflected, the axial force acting upon the airspike is shifted so that it no longer goes through the center of gravity and creates a pitching moment. This allows the bullet to create a pitching moment which can control the projectile. A basic aerodynamic analysis was done on the projectile, and subsequent wind tunnel tests through Mach 2.5 were done to prove this data. Bench top tests were also done on the system to determine the relationship of voltage to deflection of the airspike. The paper also includes considerations for setback, setforward and balloting. The paper includes a finite element analysis for the setback acceleration. The paper concludes with a system design of a beam rider projectile and simulates the trajectory of the projectile.Copyright © 2008 by ASME
Simplified automated method for the determination of d-mannoheptulose☆

Abstract A simple, automated method of estimation of d -mannoheptulose in blood and urine is presented. It requires 0.1 ml of sample and is carried out at a speed of 40 estimations per hour. Recovery and reproducibility is excellent; interference of other carbohydrates has to be carefully considered in other than physiological conditions.
Gravitational drive on oceanic plates caused by thermal contraction

PROPOSED mechanisms for the motion of lithospheric plates over the Earth's surface range from the self-drive of plates by gravitational sliding1,2, through passive response to mantle-wide convection3, to point drive by upwelling hotspots in the mantle4. All of these models depend on the distribution of effective viscosity within the mantle. Investigations5 have established the strong likelihood that a weak layer (1020 poise) exists immediately below the lithosphere, and long spatial-wavelength loadings associated with changes in the Earth's rotation6, together with the larger scale components of glacial loading5, demand that this asthenosphere be quite thin (100 km) and bounded by material from the lower mantle with a viscosity of two to four orders of magnitude higher.
Retropharyngeal spread of carcinoma of the thyroid

In the 20-year period between 1945 and 1964, 313 patients with thyroid carcinoma were studied. Review of these records disclosed 7 patients in whom retropharyngeal metastasis had occurred. Six of these patients have died and, in 4 of these, death was directly attributable to the retropharyngeal extension. In some instances, the base of the skull or the upper cervical spine was invaded, and in 4 of the patients the cranial nerves were also involved. This type of extension appears to be more common than is generally thought.
The genetic structure of mouse ornithine transcarbamylase

The gene encoding the mouse urea cycle enzyme, ornithine transcarbamylase has been isolated on five partially overlapping bacteriophage lambda clones. We have characterized the gene and found that it is split between ten exons distributed over approximately 70 kb of the X chromosome. The introns range in size from 88 bases to the relatively unusual size of approximately 26 kilobases, while the splice donor/splice acceptor sequences conform to the consensus established for other eukaryotic genes.
Second-Law Analysis of a Two-Phase Self-Pumping Solar Water Heater

In this paper entropy generated by operation of a two-phase self-pumping solar water heater under Solar Rating and Certification Corporation rating conditions is computed numerically in a methodology based on an exergy cascade. An order of magnitude analysis shows that entropy generation is dominated by heat transfer across temperature differences. Conversion of radiant solar energy incident on the collector to thermal energy within the collector accounts for 87.1 percent of total entropy generation. Thermal losses are responsible for 9.9 percent of total entropy generation, and heat transfer across the condenser accounts for 2.4 percent of the total entropy generation. Mixing in the tempering valve is responsible for 0.7 percent of the total entropy generation. Approximately one half of the entropy generated by thermal losses is attributable to the self-pumping process. The procedure to determine total entropy generation can be used in a parametric study to evaluate the performance of two-phase hot water heating systems relative to other solar water heating options.
Regenerative potentials in rat neostriatal neurons in an in vitro slice preparation.

1. Regenerative potentials in rat neostriatal neurons were studied using the in vitro slice preparation. Some of the recorded neurons were intracellularly labeled with HRP. All had the morphological characteristics of the medium spiny neuron. 2. Application of TTX (10−5 g/ml) to the superfusing medium abolished fast action potentials generated by intracellularly injected depolarizing current. Application of TEA prolonged the spike duration by decreasing its repolarizing rate without affecting rising phase. After suppression of K-conductance by TEA, depolarizing current elicited both fast and slow all or none action potentials. 3. Combined treatment with TTX and TEA revealed two types of depolarizing potentials, a slowly rising graded depolarizing potential and slow action potential. Substitution of Ca++ with Mg++ in the medium diminished the amplitude of these potentials. They were also blocked by application of Co++ into the superfusion medium. The duration of slow action potentials were increased (1) with increase in the intensity of current pulse, (2) with decrease in the resting membrane potential, and (3) with increase in the concentration of TEA in the bathing medium. 4. In the normal Ringer solution, local stimulation elicited depolarizing postsynaptic responses (DPSPs). Large DPSPs evoked by strong local stimulation triggered one or two fast action potentials. In some neurons, large DPSPs could trigger both fast and slow action potentials. They were consistently triggered after application of TEA (1 mM) to the medium. 5. When a relatively high concentration of TEA (4 mM) was applied to the Ringer solution, locally evoked DPSPs could trigger only slow action potentials. In double stimulation experiments, a large reduction in the amplitude and the duration of test DPSPs was observed up to about 150 ms interstimulus interval.
Enhancement of Vitamin-K-Dependent Protein Function by Modification of the γ-Carboxyglutamic Acid Domain: Studies of Protein C and Factor VII

Abstract Vitamin-K-dependent proteins are found in both the pro- and anti-coagulation cascades, and their use in coagulation therapies is expanding rapidly. The vitamin-K-dependent, γ-carboxyglutamic acid (Gla)-containing regions of proteins in this family are homologous and are responsible for membrane association. Site-directed mutations that enhance the membrane affinity of protein C, an anticoagulant, and of factor VII, a procoagulant, have been identified. These protein C and Factor VII mutants show enhanced activity in many assays, offering opportunities to study the role of membrane in blood clotting reactions and proteins that may have greater therapeutic value.
A new proof of a theorem by H. G. Landau on tournament matrices

Abstract H. G. Landau obtained necessary and sufficient conditions that non-negative integers r 1 , r 2 , …, r n are the row-sums of a tournament matrix. In this paper a new proof of this result is obtained.
Increased membrane fluidity implicated in acceleration of decay of post-tetanic potentiation by alcohols.

AFTER repetitive stimulation of a synapse, the efficacy of synaptic transmission may be potentiated for a period. In systems that lend themselves to detailed analyses, this posttetanic potentiation (PTP) has been shown to be due to an increased amount of transmitter released by the presynaptic neurone rather than to postsynaptic mechanisms1. We have investigated the PTP of a monosynaptic, all-or-none, excitatory postsynaptic potential (e.p.s.p.) recorded in cell R15 of the abdominal ganglion of Aplysia californica with appropriate stimulation of the right visceropleural connective, and have presented evidence that the PTP of this e.p.s.p. is based on increased transmitter release2. We have shown3 that while PTP is slightly prolonged by lowering the temperature of the preparation from 20 to 12 °C, the duration of the PTP is increased tenfold by further lowering of the temperature to 10 °C. This demonstration of a transition temperature suggested that the fluidity of critical lipids in the presynaptic membrane regulates the decay of PTP, such that PTP decays more slowly in conditions of decreased membrane fluidity. If this inference is correct, agents, such as alcohols4, that increase membrane fluidity and thus act as ‘antifreezes’, should either prevent the occurrence of the temperature transition or lower the transition temperature. These agents should also, by themselves, accelerate the rate of PTP decay and their potency should be correlated with their lipophilicity. We present here experimental evidence in support of these predictions.
The gender-stereotyped nature of christmas toys received by 36-, 48-, and 60-month-old children: A comparison between nonrequested vs requested toys

This research provides normative information on the gender-stereotyped nature of Christmas toys that children received from their parents. A list of over 500 toys was obtained from the parents of 86 children between the ages of 31 and 65 months. The toys were rated and placed into gender-stereotyped groups, and were categorized into child requested or nonrequested groups. It was found that the children had considerable input into the types of toys they received from their parents for Christmas, requesting approximately one half of the toys. Toys the children requested were judged to be more gender stereotyped than nonrequested toys. Very few boys received either requested or nonrequested toys considered stereotyped for the opposite sex. In contrast, one third of the girls received at least one toy judged to be stereotyped for the opposite sex. Also, boys appeared to develop sex-typed interests in toys at an earlier age than girls, and they requested 72%, 76%, and 75% gender-stereotyped toys in the corresponding age groups of 36-, 48-, and 60-months. The girls' sex-typed interests in toys lagged behind the boys', with girls requesting 29%, 51%, and 73% gender-stereotyped toys for the same age groups. In the nonrequested condition, parents selected types of toys judged to be traditionally more sex role neutral and emphasized musical instruments, art supplies, and educational toys for their sons and educational toys for their daughters.
BEHAVIORAL OBJECTIVES AND FLEXIBLE GROUPING IN SEVENTH GRADE MATHEMATICS

Methods of classroom management in mathematics have often taken the form of some division of the class into groups. This has been particularly true at the elementary school level. A recent review of the literature on this subject (Perkins, 1967) found that dividing students into two or more groups within the classroom is the management technique used most often to provide for individual differences in mathematics instruction. Certainly this organizational technique can be a step in the right direction. The very fact that there is more than one group to plan for assures that there will be some awareness of and planning for the differences among students. However, regardless at what level of mathematics instruction this intra-class grouping takes place, its effectiveness depends on how successfully it meets certain criteria. While many lists of such criteria have been developed (Brewer, 1966), three guidelines are considered to be among the most important: flexibility, accuracy, and appropriate material.
LEVELS OF TISSUE DIFFERENTIATION IN PRIMARY ROOTS OF PISUM SATIVUM

ALTHOUGH THERE HAS BEEN a considerable amount of research on the problem of precisely where minerals and water enter roots, plant physiologists have not yet satisfactorily answered the vexing question. Many physiologists will agree that most attempts to obtain information pertaining to the place of entrance of minerals have, in reality, resulted in data relating to the place of their accumulation. In recent years some progress has been made in designing experimental methods that have yielded information, some of which appears to be contradictory, concerning the actual place of entrance of minerals and water (Hayward et al., 1942; Hayward and Spurr, 1943; Overstreet and Jacobson, 1946; Jacobson and Overstreet, 1947; Kramer and Wiebe, 1952). In connection with this problem, question of the role played by various root tissues in the movement of minerals and water centripetally through the root has been raised. Before the relative importance of each root tissue can be assessed, it is necessary to know precisely the spatial relationships of these tissues in roots growing in various environments. If it were found that the spatial relations differed in roots growing in different environments, a new experimental tool would be at hand. It could be used in designing experiments to give us more information regarding the relative influence of various root tissues on the entrance or rate of movement of minerals and water into and through roots. Heimsch (1951) called attention to the need for such data in his statement "if the range of differentiation and maturation of vascular tissues could be modified experimentally, it might be possible to identify the substances or conditions which control this aspect of growth and determine their specific influences." A great deal of speculation appears in both anatomical and physiological literature concerning the relationships of (1) the level of differentiation of one tissue to that of others and (2) the level at which a tissue differentiates (or matures) to the level at which certain physiological processes occur. Since we have relatively few data concerning the levels of tissue differentiation and maturation in roots, it seemed desirable to discover as many of these relationships as feasible for the roots of a particular plant. MATERIAL AND METHODS.-The common garden and commercial canning pea, Pisuim sativum, was
Geometry and flexibility of DNA four-way junctions

Four-way branched DNA structures (Holliday junctions) are the key intermediates formed during genetic recombination between two duplex DNA molecules. The outcome of recombination at specific DNA sequences may depend on the 3D structure at the junction site. We have used time-resolved fluorescence resonance energy transfer methods to measure interarm distance distributions in a series of related four-way DNA junctions. The aim of these studies is to establish how the global structure and flexibility of the junction are influenced by the base sequence flanking the branch point. Energy transfer donor and acceptor dyes were conjugated to the 5' termini of the DNA strands via a C6 linker. Six pairwise combinations of labeled arms have been examined for each junction, yielding six interarm distance distributions. All the junctions we examined formed `X' shape structures by pairwise stacking of duplex arms, although there were significant differences in the range of interarm distances, depending on the junction sequence. Certain sequences appear to produce a mixture of the two possible stacking arrangements. These studies help to define the molecular interactions that dictate the crossover bias at a specific junction sequence.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Effect of reactivity loss on apparent reaction order of burning char particles

Considerable debate still exists in the char combustion community over the expected and observed reaction orders of carbon reacting with oxygen. In particular, very low values of the reaction order (approaching zero) are commonly observed in char combustion experiments. These observations appear to conflict with porous catalyst theory as first expressed by Thiele, which suggests that the apparent reaction order must be greater than 0.5. In this work, we propose that this conflict may be resolved by considering the decrease in char reactivity with burnout due to ash effects, thermal annealing, or other phenomena. Specifically, the influence of ash dilution of the available surface area on the apparent reaction order is explored. Equations describing the ash dilution effect are combined with a model for particle burnout based on single-film nth-order Arrhenius char combustion and yield an analytical expression for the effective reaction order. When this expression is applied for experimental conditions reflecting combustion of individual pulverized coal particles in an entrained flow reactor, the apparent reaction order is shown to be lower than the inherent char matrix reaction order, even for negligible extents of char conversion. As char conversion proceeds and approaches completion, the apparent reaction order drops precipitously past zero to negative values. Conversely, the inclusion of the ash dilution model has little effect on the char conversion profile or char particle temperature until significant burnout has occurred. Taken together, these results suggest that the common experimental observation of low apparent reaction orders during char combustion is a consequence of the lack of explicit modeling of the decrease in char reactivity with burnout.
Evaluation of an artificial intelligence guided inverse planning system: clinical case study.

Abstract Purpose An artificial intelligence (AI) guided method for parameter adjustment of inverse planning was implemented on a commercial inverse treatment planning system. For evaluation purpose, four typical clinical cases were tested and the results from both plans achieved by automated and manual methods were compared. Methods and materials The procedure of parameter adjustment mainly consists of three major loops. Each loop is in charge of modifying parameters of one category, which is carried out by a specially customized fuzzy inference system. A physician prescribed multiple constraints for a selected volume were adopted to account for the tradeoff between prescription dose to the PTV and dose–volume constraints for critical organs. The searching process for an optimal parameter combination began with the first constraint, and proceeds to the next until a plan with acceptable dose was achieved. The initial setup of the plan parameters was the same for each case and was adjusted independently by both manual and automated methods. After the parameters of one category were updated, the intensity maps of all fields were re-optimized and the plan dose was subsequently re-calculated. When final plan arrived, the dose statistics were calculated from both plans and compared. Results For planned target volume (PTV), the dose for 95% volume is up to 10% higher in plans using the automated method than those using the manual method. For critical organs, an average decrease of the plan dose was achieved. However, the automated method cannot improve the plan dose for some critical organs due to limitations of the inference rules currently employed. For normal tissue, there was no significant difference between plan doses achieved by either automated or manual method. Conclusion With the application of AI-guided method, the basic parameter adjustment task can be accomplished automatically and a comparable plan dose was achieved in comparison with that achieved by the manual method. Future improvements to incorporate case-specific inference rules are essential to fully automate the inverse planning process.
Face recognition as a task environment for the reference neuron model of memory

The structure of the reference neuron model and various fine tuning issues were explored within the domain of face recognition. Several faces were presented for the system to learn. Modified versions of one of the faces were then presented, and the system was asked to identify the faces. Increasing amounts of noise were added to the faces and the system's responses were noted. The system proved very capable of accurately identifying modified faces, even rivaling the ability of the human eye. Many interesting tuning and implementation issues were resolved. The system performed best with minimal numbers of neurons involved in the detection process. Another surprising result is that performance achieved was independent of the choice of features to which the neurons responded.
Shape-Controlled Synthesis of Single-Crystalline Nanopillar Arrays by Template-Assisted Vapor−Liquid−Solid Process

Highly regular, single-crystalline nanopillar arrays with tunable shapes and geometry are synthesized by the template-assisted vapor−liquid−solid growth mechanism. In this approach, the grown nanopillars faithfully reproduce the shape of the pores because during the growth the liquid catalyst seeds fill the space available, thereby conforming to the pore geometry. The process is highly generic for various material systems, and as an example, CdS and Ge nanopillar arrays with square, rectangular, and circular cross sections are demonstrated. In the future, this technique can be used to engineer the intrinsic properties of NPLs as a function of three independently controlled dimensional parameters - length, width and height.
Stereoscopic visualization of laparoscope image using depth information from 3D model

Laparoscopic surgery is indispensable from the current surgical procedures. It uses an endoscope system of camera and light source, and surgical instruments which pass through the small incisions on the abdomen of the patients undergoing laparoscopic surgery. Conventional laparoscope (endoscope) systems produce 2D colored video images which do not provide surgeons an actual depth perception of the scene. In this work, the problem was formulated as synthesizing a stereo image of the monocular (conventional) laparoscope image by incorporating into them the depth information from a 3D CT model. Various algorithms of the computer vision including the algorithms for the feature detection, matching and tracking in the video frames, and for the reconstruction of 3D shape from shading in the 2D laparoscope image were combined for making the system. The current method was applied to the laparoscope video at the rate of up to 5 frames per second to visualize its stereo video. A correlation was investigated between the depth maps calculated with our method with those from the shape from shading algorithm. The correlation coefficients between the depth maps were within the range of 0.70-0.95 (P<0.05). A t-test was used for the statistical analysis.
Action Principle in Statistical Dynamics

We discuss a least-action principle characterizing ensemble-averages in statistical dynam­ ics, based upon "effective actions" defined as in quantum field-theory. These generalize to all system variables the Onsager-Machlup actions of thermodynamic fluctuation theory. In the statistical steady-state, the variational principles discussed are related to the "thermodynam­ ical formalism" for chaotic dynamical systems. Non-perturbative methods of field-theory can be applied to approximate the effective actions: instantons, 1/ N-expansion, Hartree-Fock, Rayleigh-Ritz, etc. In particular, the Rayleigh-Ritz method is shown to be closely related to traditional moment-closure schemes. Some concrete applications of the variational meth­ ods are outlined, e.g., to free decay of homogeneous, isotropic Navier-Stokes turbulence at high Reynolds number. "Fluctuation-dissipation relations" are obtained for the strength of turbulence-generated eddy noise in terms of mean dissipation characteristics. The rela­ tion of the effective action to dissipation and transport characteristics was already noted by Onsager, who pointed out that the associated variational principles generalize the hydro­ dynamic least-dissipation principle of Rayleigh. We briefly discuss the application of such principles to pattern-selection far from equilibrium.
Locus coeruleus lesions and resistance to extinction of a classically conditioned response: Involvement of the neocortex and hippocampus

Abstract Bilateral electrolytic lesions of the locus coeruleus were made in rabbits prior to classical conditioning of the nictitating membrane (NM) response. After recovery, the animals received one session of unpaired training followed by 3 days of paired acquisition training and 4 days of unpaired training (extinction). At the end of extinction norepinephrine (NE) and dopamine (DA) levels were measured in several brain regions. Each lesioned animal was placed into one of two groups according to whether or not the animal exhibited a significant depletion of cortical/hippocampal NE. A third group was formed by non-lesioned controls. There were no significant differences between the 3 groups during acquisition; however, during days 3 and 4 of unpaired extinction the group with cortical/hippocampal NE depletion showed significantly larger NM responses on the conditioned stimulus-alone trials than either of the two control groups. This extinction deficit appeared mainly in the unconditioned stimulus-period component of the tone-alone conditioned responses. The magnitude of the extinction deficit was highly correlated with the depletion of NE in both cortical and hippocampal samples but not with the depletion of NE in the hypothalamus/mid-thalamus, or cerebellum.
The Norwood procedure using a right ventricle-pulmonary artery conduit: comparison of the right-sided versus left-sided conduit position.

Objective We proposed that a right-sided right ventricle–pulmonary artery conduit during the stage I Norwood procedure would facilitate pulmonary artery reconstruction during the stage II procedure. Methods Between 2002 and 2006, 153 patients underwent Norwood stage I reconstruction with a right ventricle–pulmonary artery conduit (125 in the right-sided group and 28 in the left-sided group). The previous 150 consecutive classic Norwood procedures (1997–2002) were used as a control group. Outcomes from stages I and II were analyzed, including ventricular function and pulmonary artery morphology. Results The 30-day survival was 88% (110/125) in the right-sided group, 75% (21/28) in the left-sided group, and 70% (105/150) in the control group ( P P = .001). Survival at 6 months demonstrated a significant survival benefit in the right-sided right ventricle–pulmonary artery conduit group over the control group ( P = .009, log-rank test). There was no difference in ventricular function between the groups and no regional dyskinesia associated with the right ventricle–pulmonary artery conduit. Despite larger branch pulmonary artery size in the right ventricle–pulmonary artery conduit groups (compared with the control group), central pulmonary artery stenoses were common (62% in the right conduit and 80% in the left conduit). Bypass and ischemic times at stage II were 49 ± 10 and 23 ± 13 minutes in the right-sided group compared with 61.5 ± 9.5 and 31 ± 14 minutes in the left-sided group ( P P = .03, respectively). The 30-day mortality after the stage II procedure was 1.3% (1/76) in the right-sided group, 0% (0/18) in the left-sided group, and 3.3% (3/90) in the control group. Conclusion The right-sided conduit is a safe technique and has improved 30-day and overall post–stage II survival compared with that seen with the classic Norwood procedure. The right ventricle–pulmonary artery conduit is associated with central pulmonary artery stenosis but good development of the branch pulmonary arteries and preservation of ventricular function. The right-sided conduit significantly reduces cardiopulmonary bypass times at stage II.
Prescribing the length of rational Be´zier curves

Abstract Theorems and corresponding algorithms are presented which produce a rational Bezier curve of a specified arc length subject to certain constraints. Extraneous inflection points are avoided. The problem is reduced to expressing the arc length as a function of a single variable. A general theorem from a previous paper of the authors is used which gives conditions under which the arc length function is convex or strictly convex. An algorithm to automatically choose the initial parameters for the secant method will produce a solution to this problem with performance comparable to the Newton-Raphson method. Theory and algorithms for rational parametric curves are presented. It is shown that in certain cases rational parametric curves of degree three can be used while polynomials of bounded degree cannot.
Network analysis of production smootewg

The purpose of this paper is to show, on an example, how rather forbidding algebra may often be avoided by quite elementary considerations concerning flows in a properly constructed flow chart or network. The problem of production smoothing is incidental in the sense that it could have been replaced by other illustrations of the technique.
Loosening Links? School-to-Work Transitions and Institutional Change in Russia since 1970

The article analyzes variation in the association between education and first occupational class (the "EC association") among Russians from four consecutive labor force entry cohorts spanning 1970-2000 and by sex. Cross-national comparative research suggests that national institutions affect the magnitude of the EC association. However, loglinear models provide no support for the view that the institutional changes associated with the demise of the Soviet system influenced the pattern or magnitude of the EC association in Russia. The only changes in the EC association predated the major institutional changes. The findings confirm research showing continuity in other aspects of stratification in post-Soviet Russia despite rapid institutional changes connected with market transition. Although there are several alternative explanations for the lack of change in the EC association, the null results suggest that the relationship between institutional arrangements and patterns of stratification is not as straightforward as cross-sectional analyses might suggest. Structural forces and policies also shape patterns of stratification, both independently of and in conjunction with institutions.
Efficiency Enhancement in Organic Photovoltaic Cells: Consequences of Optimizing Series Resistance

Here, means to enhance power conversion efficiency (PCE or η) in bulk-heterojunction (BHJ) organic photovoltaic (OPV) cells by optimizing the series resistance (Rs)—also known as the cell internal resistance—are studied. It is shown that current state-of-the-art BHJ OPVs are approaching the limit for which efficiency can be improved via Rs reduction alone. This evaluation addresses OPVs based on a poly(3-hexylthiophene):6,6-phenyl C61-butyric acid methyl ester (P3HT:PCBM) active layer, as well as future high-efficiency OPVs (η > 10%). A diode-based modeling approach is used to assess changes in Rs. Given that typical published P3HT:PCBM test cells have relatively small areas (∼0.1 cm2), the analysis is extended to consider efficiency losses for larger area cells and shows that the transparent anode conductivity is then the dominant materials parameter affecting Rs efficiency losses. A model is developed that uses cell sizes and anode conductivities to predict current–voltage response as a function of resistive losses. The results show that the losses due to Rs remain minimal until relatively large cell areas (>0.1 cm2) are employed. Finally, Rs effects on a projected high-efficiency OPV scenario are assessed, based on the goal of cell efficiencies >10%. Here, Rs optimization effects remain modest; however, there are now more pronounced losses due to cell size, and it is shown how these losses can be mitigated by using higher conductivity anodes.