cssi/SciSciGPT-SciSciNet huggingface dataset:
Symposium: Diffusing communication into the secondary school curriculum

Training students to function as group facilitators is proposed as a means of diffusing the use of small group discussion into classes other than speech communication. Advantages of training student leaders include: (1) extending and developing the communication program, (2) developing leadership qualities and communication skills of students, (3) providing an alternative teaching strategy for teachers, and (4) allowing students to experience small group discussion in a variety of contexts.
Polyrotaxanes: Synthetic methodologies & characterization

The synthesis of polyrotaxanes, comprised of linear macromolecules threaded through cyclic species, may be accomplished by either of two strategies: (1) statistical threading, in which the macrocycle is used as solvent and threading is predominantly entropically driven, or (2) template threading, involving an enthalpic driving force such as charge transfer or metal complexation. This paper summarizes our efforts in this field by describing syntheses by both step and chain growth methodologies and the characterization of the resultant polyrotaxanes. Examples include polyesters, polyethers, polyurethanes, polystyrene and polyacrylonitrile. The polyrotaxanes possess properties (thermal, solubility, mechanical, etc.) that differ from the corresponding linear polymers. In some systems phase separation occurs, producing morphologies that consist of crystalline macrocycles and either amorphous or crystalline linear backbones; these results demonstrate the ability of the macrocycles to move along the linear backbone in the melt without dethreading.
Our traumatized society

Abstract Our traumatized society needs the joint efforts of people working in safety and surgery. There is wide agreement among experienced persons in the field of traffic safety that if the techniques now known and tested were fully applied, traffic accidents could be cut in half. Meanwhile, research is expanding to develop even more effective accident prevention programs. Kulowski [31] calls upon doctors to participate in the safety movement: “The epidemic number and variegated nature of motorist injuries and deaths are tending to pull all types of persons, groups, and disciplines together in a common effort to reduce this toll. Since the most significant results of motor vehicle accidents are personal injuries to people, medicine stands in the vanguard …”.
Factors Affecting Heavy-Duty Diesel Vehicle Emissions

Societal and governmental pressures to reduce diesel exhaust emissions are reflected in the existing and projected future heavy-duty certification standards of these emissions. Various factors affect the amount of emissions produced by a heterogeneous charge diesel engine in any given situation, but these are poorly quantified in the existing literature. The parameters that most heavily affect the emissions from compression ignition engine-powered vehicles include vehicle class and weight, driving cycle, vehicle vocation, fuel type, engine exhaust aftertreatment, vehicle age, and the terrain traveled. In addition, engine control effects (such as injection timing strategies) on measured emissions can be significant. Knowing the effect of each aspect of engine and vehicle operation on the emissions from diesel engines is useful in determining methods for reducing these emissions and in assessing the need for improvement in inventory models. The effects of each of these aspects have been quantified in this paper to provide an estimate of the impact each one has on the emissions of diesel engines.
Familism, substance abuse, and sexual risk among foster care alumni

Abstract Prior research has suggested that youth growing up in the foster care system are among the United States' most vulnerable populations. Other research has documented the association between positive family relationships and less frequency of negative behaviors in foster care populations. We, therefore, sought to examine how dimensions of familism predict substance abuse and sexual risk in a sample of ( N = 100) foster care alumni. Although greater dimensions of familism did not predict less substance abuse and sexual risk, participants' quality of relationship with individual family members was associated with less substance abuse and sexual risk.
Toward CFTR Structural Dynamics During Ion Channel Gating

While CFTR catalyses the irreversible hydrolysis of its physiological ligand (ATP), there is disagreement about whether CFTR channel gating is a thermally driven process (Aleksandrov & Riordan 1998 FEBS Lett. 431:97, Csanady et al., 2006 JGP128:509). Knowing the answer to this question is of fundamental importance to understand problems leading to CFTR functional failure in cystic fibrosis, an inherited disease of high morbidity and mortality. Although CFTR single channel recordings do not provide a direct measure of enzymatic activity, they do provide an opportunity to establish the relationship between ATP binding and hydrolysis at the nucleotide binding domains (NBDs) and channel gating. The use of Rate Equilibrium Free Energy Relationship (REFER) is a possible way to probe structural dynamics in an ion channel gating (Auerbach, 2005 PNAS 102:1408). We use this conceptual framework to reveal the role of ATP hydrolysis in CFTR ion channel function. The REFER graphs for the set of nucleotide ligands have slope Φ ≈1 for the openings and Φ ≈ 0 for the closings. This means that the nucleotide triphosphate interaction with the binding sites is required for channel opening. In contrast, the ion channel transition from the open to the closed state occurs independently of any events in the binding sites. This could not be interpreted by conventional mechanical models of molecular devices where the mobile species are levered from the initial to the final position by force generated in the binding sites. However this behavior fits very well to Brownian ratchet models where internal thermal diffusion is a key element of the process, and specific interactions induce no mechanical movements directly but instead are used to trap favorable fluctuations.
God and the Natural World in the Seventeenth Century: Space, Time and Causality

The employment by seventeenth-century natural philosophers of stock theological notions like creation, immensity, and eternity in the articulation and justification of emerging physical programs disrupted a delicate but longstanding balance between transcendent and immanent conceptions of God. By playing a prominent (if not always leading) role in many of the major scientific developments of the period, God became more intimately involved with natural processes than at any time since antiquity. In this discussion, I am particularly concerned with the causal and spatio-temporal relations between God and nature in the seventeenth century as recent scholarship has revealed how dramatically traditional conceptions of these relations were transformed by philosophers and scientists like Descartes, Malebranche, More, and Newton.
Decreased Binding of 14 C-Homogentisic Acid induced by Ascorbic Acid in Connective Tissues of Rats with Experimental Alcaptonuria

ADULTS with alcaptonuria develop a destructive arthritis secondary to the deposition of a melanin-like pigment in their connective tissues, especially skin, tendon and Cartilage (ochronosis). The biochemical steps leading to ochronosis involve the chemical binding of oxidized and/or polymerized derivatives of homogentisic acid (HGA), the metabolite accumulating in the blood in alcaptonuria, to these connective tissues, with subsequent physico-chemical alterations in the properties of collagen1. HGA seems to be converted to an oxidized polymerized derivative through the formation of a labile, oxidized intermediate, benzoquinone acetic acid (BQA). Both steps in this conversion are catalysed by HGA polyphenol oxidase, a copper-requiring enzyme2.
Current status of product for endoscopic surgery in Korea.

Endoscopic surgeries are popularly performed these days because of the advantages in rehabilitation and cosmetic aspects. But some accompanying disadvantages should not be neglected. For surgeons unfamiliar with the endoscopic surgery techniques, the operation takes more time and dangerous complications may occur more frequently. Most endoscopic surgery techniques, also called minimal invasive surgery techniques, were developed and disseminated from Europe and the U.S. They require specialized equipment and instruments that are expensive, and for this reason the total operation cost compared to conventional open surgery is higher. Despite all the advantages of endoscopic surgery, the high cost due to the of imported specialized instruments is holding back its spread in Korea. The development of self-supporting endoscopic instruments in Korea is mandatory for reducing the expense, and in this regard I have designed trocars of various size, specimen retrieval bags, suction and irrigation tubing sets, gasless laparoscopic surgery sets, scissors of various types, and forceps. Instruments used in suture and ligation which are currently under development will also soon be introduced.
Biochemical and functional properties of the full-length cation-dependent mannose 6-phosphate receptor expressed in Pichia pastoris.

Abstract A glycosylation-deficient, full-length cation-dependent mannose 6-phosphate receptor (CD-MPR) containing a yeast signal sequence was expressed in Pichia pastoris using the constitutive promoter of the PGAP gene. The membrane-bound receptor was solubilized using detergents and purified by pentamannosyl phosphate–agarose affinity chromatography. Equilibrium binding studies identified a binding affinity of 2 nM for the lysosomal enzyme, β-glucuronidase. To probe the linkage specificity of the recombinant CD-MPR, inhibition binding studies were conducted using non-phosphorylated oligomannoses which demonstrated that Manα1,2Man exhibits a 4-fold higher inhibition than Manα1,3Man and Manα1,6Man. The receptor was capable of associating into oligomeric forms and enzymatic deglycosylation revealed the presence of high-mannose sugars at the single potential N-glycosylation site. Mass spectrometric analysis revealed that the receptor was palmitoylated at the two potential cysteines in its cytoplasmic domain. In conclusion, the full-length CD-MPR produced in P. pastoris is structurally and functionally suitable for crystallization studies.
In-cell click labelling of small molecules to determine subcellular localisation.

Small molecule fluorometric boron dipyrromethene probes were developed to bind hepatitis C virus-encoded NS5A protein and aid subcellular distribution studies. These molecules did not co-locate with NS5A, therefore alternative ‘silent’ azide reporters were used to obtain a more relevant picture of their distribution. Following pre-incubation with replicon cells, click chemistry was used to append a fluorophore to the azide that confirmed the co-localisation of the small molecule with the NS5A protein, thus providing greater insight into the antiviral mode of action of this chemotype.
Classification of the restricted simple Lie algebras

Soit L une algebre de Lie simple restreinte de dimension finie sur un corps algebriquement clos F de caracteristique p>7. Alors L est de type classique ou de Cartan
Medical Disinterest in Human-Animal Bond Research?

(1995). Medical Disinterest in Human-Animal Bond Research? Anthrozoos: Vol. 8, No. 3, pp. 130-131.
The pathogenesis of Sweet's syndrome.

To the Editor: Wakefield et al. are to be commended for their excellent review ofcolony-stimulating factors (J AM ACAD DERMATOL 1990;23:903-12). In their discussion of both adverse effects and colony-stimulating factors in dermatology, they refer to the development of Sweet's syndrome in a patient with hairy cell leukemia treated with granulocytecolony-stirnulating factor (G-CSF).1 As mentioned by the authors, the diagnosis of Sweet's syndrome in this patient had not been confirmed by a Iesional skin biopsy; we have previously addressed this issue and contest the diagnosis of Sweet's syndrome in this patient.2 Actually, the case report reveals that the patient had a skin biopsy-proven leukocytoclastic vasculitis before receiving G-CSF and had enlargement of existing lesions and similar-appearing new lesions after receiving G-CSF therapy. I Cutaneous leukocytoclastic vasculitis has been observed in several patients with hairy cell leukemia.3 Hence, treatment of the patient of Glaspy et a1.1 with G-CSF probably exacerbated her underlying hairy cell leukemia-related leukocytoclastic vasculitis; therefore, on the basis of the available information, her skin lesions did ~ot represent either malignancy-associated Sweet's syn4rpme or G-CSF-induced Sweet's syndrome. Colony-stimulating factors may participate, directly or indirectly, in the origin ofseveral dermatologic conditions. Journal of the American Academy of Dermatology
Education: teaching computer graphics visual literacy to art and computer science students

Instructors in both art and computer science departments experience difficulties in motivating students to develop a visual literacy in computer graphics. Although a highly prized skill in industry, visual literacy is intimidating to computer science students because they are uneasy about using their eyes to examine computer-synthesized images. Even though they are used to using their eyes for acquiring information, the topics of analysis and interpretation intimidate art students. Further, art students may not have as much background to understand the technical terminology. This first column in a two-part series discusses an interdisciplinary approach for teaching visual literacy that overcomes these obstacles. With this approach students become more familiar with the limits and possibilities of the medium of computer graphics, learn how to analyze and talk about what visual images might mean and develop a deeper understanding of time constraints. In addition, they gain confidence with technological terminology and the idea of suggesting alternative algorithms to create a desired visual "look." As a result, both computer science and art students become more able to communicate effectively about and with visual imagery.
The effect of precursor and preparation conditions of MgO on the CO2 reforming of CH4 over NiO/MgO catalysts

MgO supports were prepared by decomposing various precursors at various temperatures and for various durations. The effect of the precursor and conditions employed to prepare MgO on the conversions of CO2 and CH4, and the CO yield over the reduced NiO/MgO catalyst in the CO2 reforming of CH4 was investigated. The yield and the conversions increase with reaction time and attain constant values. The latter values as well as the induction time depend upon the precursor and conditions employed to prepare MgO.
Release of Dissolved Amino Acids by Marine Zooplankton

Marine net zooplankton release dissolved amino acids into the water. Release rates are positively correlated with temperature and can be estimated by the equation: Release rate, (milligrams of alpha-amino nitrogen per gram dry weight of zooplankton per day) = 1.0 x temperature (°C) —5.9. Release rates appeared to be independent of the taxonomic composition of the test samples, which were variously dominated by copepods, salps, chaetognaths, coelenterates, or radiolarians. These amino acids constitute an important source of dissolved organic matter in the sea.
Electrical surface properties of semi-insulating and ion implanted GaAs revealed by thermo-optical acousto-electric voltage method☆

Abstract A thermo-optical acousto-electric voltage method is used for the determination of electrical surface properties of GaAs materials. Measurements conducted on semi-insulating substrates, some with an implanted layer, allow determination of surface conduction type, impurity activation, and photoconductivity behavior. The spectroscopic nature of the technique allows detection and characterization of energy levels in the semiconductor band gap. For the samples tested a 0.87 eV level attributed to chromium and a broad distribution of acceptor type surface states about 1.0–1.05 eV from valence band are reported. The main advantages of this measurement method are its effectiveness for the study of semiconductors over a wide range of resistivities and its nondestructive character.
Disfluencies, utterance length, and linguistic complexity in nonstuttering children

Abstract Ten male and ten female children provided spontaneous language samples and participated in modeling procedures employed to evoke four sets of utterances representing two levels of utterance length and two levels of linguistic complexity. Analysis suggested significantly greater rates for overall disfluencies and “stutterings” (part-word repetitions, word repetitions, disrhythmic phonations, and tense pauses) occured in those modeling tasks that evoked linguistically more complex utterances. However, sex and length of utterance appeared to be related to increased overall disfluency rates as well. Theoretical and clinical implications are discussed.
Confinement of quarks in nuclear matter

Abstract The transition from low density nuclear matter to high density quark matter can, it is argued, take place in two steps: first, a percolation transition at (subnuclear densities, if the radius of the nucleon is ⪅1 fm) in which the quarks become deconfined but still remain localized, followed by an unbinding transition at higher density, in which the matter becomes a uniform quark Fermi liquid.
Intravascular occluding device using a modified Gianturco stent as a coil cage.

JVIR 2000; 11:221–224 A variety of methods have been successfully used to achieve intravascular occlusion. In this technical note we describe successful percutaneous closure of an 8-mm-diameter H-graft portacaval shunt. The technique involved deployment of a modified Gianturco Z stent (Cook, Bloomington, IN) to function as a cage to contain coil emboli with the shunt itself, with reduced risk of proximal or distal coil embolization across the shunt. A long 8-F introducer sheath (Cordis/Johnson & Johnson Interventional Systems, Warren, NJ) was used to introduce the coil cage from a transfemoral venous approach.
Determination Of Mobility And Trafficability Indicators With Multifrequency Imaging Radar

Photoanalysis of coastal areas can give ambiguous results when parameters such as mobility and trafficability need be determined. Multiband imaging radar can augment or replace photography for such applications. Preliminary evidence shows that L-band imaging radar will (1) penetrate most wetlands vegetation species to delineate obscured shorelines, and (2) discriminate varying levels of substrate saturation and thus, potentially, quantify varying degrees of trafficability. We know that X-band radar can map many species of wetlands vegetation with good accuracy. The combination of L- and X-bands should provide a significant breakthrough for wetlands reconnaissance and mapping.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Design and operation of a continuous 13C and 15N labeling chamber for uniform or differential, metabolic and structural, plant isotope labeling

Tracing rare stable isotopes from plant material through the ecosystem provides the most sensitive information about ecosystem processes; from CO2 fluxes and soil organic matter formation to small-scale stable-isotope biomarker probing. Coupling multiple stable isotopes such as (13)C with (15)N, (18)O or (2)H has the potential to reveal even more information about complex stoichiometric relationships during biogeochemical transformations. Isotope labeled plant material has been used in various studies of litter decomposition and soil organic matter formation(1-4). From these and other studies, however, it has become apparent that structural components of plant material behave differently than metabolic components (i.e. leachable low molecular weight compounds) in terms of microbial utilization and long-term carbon storage(5-7). The ability to study structural and metabolic components separately provides a powerful new tool for advancing the forefront of ecosystem biogeochemical studies. Here we describe a method for producing (13)C and (15)N labeled plant material that is either uniformly labeled throughout the plant or differentially labeled in structural and metabolic plant components. Here, we present the construction and operation of a continuous (13)C and (15)N labeling chamber that can be modified to meet various research needs. Uniformly labeled plant material is produced by continuous labeling from seedling to harvest, while differential labeling is achieved by removing the growing plants from the chamber weeks prior to harvest. Representative results from growing Andropogon gerardii Kaw demonstrate the system's ability to efficiently label plant material at the targeted levels. Through this method we have produced plant material with a 4.4 atom%(13)C and 6.7 atom%(15)N uniform plant label, or material that is differentially labeled by up to 1.29 atom%(13)C and 0.56 atom%(15)N in its metabolic and structural components (hot water extractable and hot water residual components, respectively). Challenges lie in maintaining proper temperature, humidity, CO2 concentration, and light levels in an airtight (13)C-CO2 atmosphere for successful plant production. This chamber description represents a useful research tool to effectively produce uniformly or differentially multi-isotope labeled plant material for use in experiments on ecosystem biogeochemical cycling.
In Vitro Metabolism of Aromatic Nitriles

Studies on the metabolic fate of aromatic nitriles, in contrast to their aliphatic counterparts, have been minimal and the subject of controversy. The in vitro metabolic fate of several aromatic nitriles with varying substituents was investigated by using rat liver subcellular fractions, with a particular emphasis on the nitrile moiety. Benzonitriles and 4-cyanophenols underwent oxidative metabolism to produce ring-hydroxylated metabolites. On the other hand, 2-cyanophenol was resistant to metabolism. o-Tolunitrile was metabolized and produced o-cyanobenzyl alcohol and phthalide. Phthalide, however, was chemically derived from o-cyanobenzyl alcohol, the initial metabolite. 4-Nitrobenzonitrile was resistant to oxidation on the ring, but was readily reduced to the corresponding amine metabolite under both aerobic and anaerobic conditions. Nitroxynil (3-iodo-4-hydroxy-5-nitrobenzonitrile) was metabolized to produce 3-iodo-4-hydroxy-5-nitrobenzamide and 3-iodo-4-hydroxy-5-nitrobenzoic acid. The enzyme(s) responsible for this hydrolytic metabolism was primarily localized in the cytosol. Among the nitriles tested, o-tolunitrile and nitroxynil produced metabolites in which the nitrile moiety was modified. Nitroxynil, however, was the only compound that was directly metabolized on the nitrile moiety by the rat liver enzyme(s).
Load Transfer Control for a Gantry Crane with Arbitrary Delay Constraints

This paper describes a method to move the load of a gantry crane to a desired position in the presence of known, but arbitrary, motion-inversion delays as well as cart acceleration constraints. The method idea is based on a phase-plane analysis of the linearized model. In order to limit residual pendulation at the goal position, the method is extended to account for quadratic and cubic nonlinearities. The method of multiple scales is used to determine an approximate solution to the nonlinear equations of motion, thus providing a more accurate measure of the frequency of the oscillations. The nonlinear approach is very successful in limiting residual oscillations to very small values (less than 1 degree of amplitude), offering a reduction, with respect to the linear case, of as much as two orders of magnitude. Finally, this method offers a rationale for the future development of a controller for suppression of load oscillations in ship-mounted cranes in the presence of arbitrary delays.
Invasive mediastinal staging of lung cancer: ACCP evidence-based clinical practice guidelines (2nd edition).

Background The treatment of non-small cell lung cancer (NSCLC) is determined by accurate definition of the stage. If there are no distant metastases, the status of the mediastinal lymph nodes is critical. Although imaging studies can provide some guidance, in many situations invasive staging is necessary. Many different complementary techniques are available. Methods The current guidelines and medical literature that are applicable to this issue were identified by computerized search and were evaluated using standardized methods. Recommendations were framed using the approach described by the Health and Science Policy Committee of the American College of Chest Physicians. Results Performance characteristics of invasive staging interventions are defined. However, a direct comparison of these results is not warranted because the patients selected for these procedures have been different. It is crucial to define patient groups, and to define the need for an invasive test and selection of the best test based on this. Conclusions In patients with extensive mediastinal infiltration, invasive staging is not needed. In patients with discrete node enlargement, staging by CT or positron emission tomography (PET) scanning is not sufficiently accurate. The sensitivity of various techniques is similar in this setting, although the false-negative (FN) rate of needle techniques is higher than that for mediastinoscopy. In patients with a stage II or a central tumor, invasive staging of the mediastinal nodes is necessary. Mediastinoscopy is generally preferable because of the higher FN rates of needle techniques in the setting of normal-sized lymph nodes. Patients with a peripheral clinical stage I NSCLC do not usually need invasive confirmation of mediastinal nodes unless a PET scan finding is positive in the nodes. The staging of patients with left upper lobe tumors should include an assessment of the aortopulmonary window lymph nodes.
Clogging of an Effluent Dominated Semiarid River: A Conceptual Model of Stream-Aquifer Interactions

: Water managers in arid and semiarid regions increasingly view treated wastewater (effluent) as an important water resource. Artificial recharge basins allow effluent to seep into the ground relieving stressed aquifers, however these basins frequently clog due to physical, chemical, and biological processes. Likewise effluent is increasingly used to maintain perennial base flow for dry streambeds, however, little is known about the impact of effluent on streambed hydraulic conductivity and stream-aquifer interactions. We address this issue by investigating: if a clogging layer forms, how the formation of a clogging layer alters stream-aquifer connections, and what hydrologic factors control the formation and removal of clogging layers. We focused on the Upper Santa Cruz River, Arizona where effluent from the Nogales International Waste Water Treatment Plant sustains perennial flow. Monthly sampling, along a 30 km river reach, was done with two foci: physical streambed transformations and water source identification using chemical composition. Historical dataset were included to provide a larger context for the work. Results show that localized clogging occurs in the Upper Santa Cruz River. The clogging layers perch the stream and shallow streambed causing desaturation below the streambed. With these results, a conceptual model of clogging is established in the context of a semiarid hydrologic cycle: formation during the hot premonsoon months when flow is nearly constant and removal by large flood flows (>10 m3/s) during the monsoon season. However, if the intensity of flooding during the semiarid hydrologic cycle is lessened, the dependent riparian area can experience a die off. This conceptual model leads us to the conclusion that effluent dominated riparian systems are inherently unstable due to the clogging process. Further understanding of this process could lead to improved ecosystem restoration and management.
Effect of microbial antigens on irradiation mortality in mice.

Irradiation mortality is reduced by approximately 50% in mice injected with zymosan (1000 gamma ) or with thermostable antigens from Proteus morganii, Klebsiella pneumoniae, or Escherichia coli. Soluble antigens from Gram-positive organisms, however, are ineffective. The greatest reduction of mortality is obtained by means of a Typhoid-Paratyphoid vaccine. (auth)
A study of real-time query expansion effectiveness

In this poster, we describe the study of an interface technique that provides a list of suggested additional query terms as a searcher types a search query, in effect offering interactive query expansion (IQE) options while the query is formulated. Analysis of the results shows that offering IQE during query formulation leads to better quality initial queries, and an increased uptake of query expansion. These findings have implications for how IQE should be offered in retrieval interfaces.
Symbiosis within a symbiosis: Intracellular bacteria within the endosymbiotic protistNephromyces

The marine protistNephromyces Giard, 1888 is a chronic endosymbiont of molgulid tunicates. Ultrastructural and cytochemical studies of this protist, isolated from molgulid hosts collected from the Pacific, Atlantic and Gulf Coasts of the United States, indicate thatNephromyces is itself chronically infected with Gramnegative, intracellular bacteria. Molgulid tunicates are thus the locus of a nested,tripartite endosymbiosis. Intracellular bacteria are present in both trophic and reproductive stages ofNephromyces, suggesting that the bacterial-Nephromyces symbiosis is an hereditary association. The presence of endosymbionts inNephromyces raises the possibility that some ofNephromyces' metabolic characteristics, in particular its high urate oxidase activity, might be supplied not byNephromyces itself, but rather by its intracellular bacteria, possibly functioning as peroxisomal analogues.
Nocturnal aerial predation of fireflies by light-seeking fireflies.

Female Photuris fireflies guided by their prey9s luminescence attack flying fireflies at night. They sometimes use this hunting tactic together with prey attraction by mating-signal mimicry. Such predation could have been a major factor in the evolution of signaling behavior of American fireflies. Nocturnal aerial predation by an insect and attack guidance on energy emitted by airborne prey have not previously been reported.
A prospective randomized comparison of direct current and radiofrequency ablation of the atrioventricular junction

Objectives. The purpose of this study was to compare direct current and radiofrequency ablation of the atrioventricular (AV) junction in a prospective randomized fashion, Background. Catheter ablation of the AV junction can be performed using either direct current shocks or radiofrequency energy. To date, these two techniques have never been compared prospectively or in a randomized study. Methods. Forty patients with drug-refractory uncontrolled atrial fibrillation-flutter (38 patients) or inappropriate sinus tachycardia (2 patients) were randomly assigned to undergo direct current ablation (20 patients) using up to four shocks of 200 to 300 J or radiofrequency ablation (20 patients) using up to 15 applications of 16 to 25 W for 30 s. If complete AV block was not successfully induced, the ablation procedure was repeated using the alternate type of energy. A rate-responsive ventricular pacemaker was implanted in each patient. The intrinsic escape rhythm was evaluated 15 min, 2 days and 3, 6 and 12 months after ablation. Results. Persistent complete AV block was successfully induced during the first ablation session in 13 (65%) of 20 patients randomly assigned to undergo direct current ablation, compared with 19 (95%) of 20 patients randomly assigned to undergo radiofrequency ablation (p < 0.05). Each patient whose first ablation attempt failed had a successful outcome with the alternate type of energy. The overall efficacy of radiofrequency ablation (26 [96%] of 27 patients) was significantly greater than that of direct current ablation (14 [67%] of 21 patients, p < 0.01). The duration of the direct current and radiofrequency ablation sessions did not differ significantly. The mean peak plasma creatine kinase MB fraction concentration was significantly higher after direct current ablation (58 ± 29 IU/liter) than after radiofrequency ablation (2 ± 2 IU/liter) (p < 0.001). An escape rhythm was present 15 min after ablation in an equal proportion of patients undergoing direct current and radiofrequency ablation (78% and 85%, respectively, p = 0.6). An escape rhythm was present in all patients 3,6 and 12 months after ablation. The mean escape rhythm cycle length 15 min after direct current ablation (2,074 ± 677 ms) was significantly longer than that 15 min after radiofrequency ablation (1,460 ± 294 ms) (p < 0.05); however, the mean escape rhythm cycle lengths did not differ significantly at 2 days or 3, 6 or 12 months after ablation. Immediate arrhythmic complications did not occur after either procedure. One patient died suddenly 6.5 months after direct current ablation. Conclusion. Radiofrequency ablation of the AV junction is more efficacious and safer than direct current ablation and should be the preferred method for inducing complete AV block in patients who are appropriate candidates for ablation of AV conduction.
An electromyographic study of the pectoralis major in Atelines and Hylobates, with special reference to the Evolution of a pars clavicularis

Among primates there is striking variation in the extent of the origin of pectoralis major from the clavicle. A significant clavicular attachment (pars clavicularis) occurs only in Alouatta, Lagothrix, Hylobates, Pan (troglodytes, paniscus and gorilla), and Homo. Interpreting this trait in nonhuman primates as an adaptation to frequent use of a mobile forelimb in climbing and suspension is contraindicated by the absence of a clavicular origin in Ateles and Pongo. We have undertaken a telemetered electromyographic study to determine any special role of the most cranial part of the pectoralis major in comparison to its caudal part, and to the deltoid, during vertical climbing, pronograde quadrupedalism, and armswinging in Ateles, Lagothrix, Alouatta, and Hylobates. The results show that the cranial pectoralis major possesses a role not shared by the caudal fibers: initiation of the recovery phase of the locomotor cycle. When ability to execute rapid or powerful recovery of the adducted forelimb is required in an animal with a shoulder joint lying on a plane cranial to that of the manubrium, the movement will be facilitated if the origin of the pectoralis major is extended onto the clavicle. Such is the case in nonhuman primates possessing this trait. The absence of a clavicular origin in Ateles and Pongo may be related to diminished selective pressures to perfect locomotor modes such as pronograde quadrupedalism, armswinging, or climbing thick vertical trunks, that demand rapid or powerful recovery of the adducted forelimb. If the arboreal ancestor of humans had evolved a clavicular origin of pectoralis major, this animal would be preadapted for certain uses of the forelimb in its bipedal descendant.
A comparison of estimators of a common correlation coefficient

It is often of interest to test the hypothesis that all off-diagonal elements of the correlation matrix of a multivariate normal distribution are equal. If the hypothesis of equal correlation can be accepted, it then may be of interest to estimate the common correlation coefficient. In this paper, four estimators of the common correlation are compared in terms of bias, variance, mean squared error, adequacy of the normal approximation, and ease of calculation. The average sample correlation is seen to be comparable to the other estimators and is recommended here since it is the easiest to calculate. The estimators are compared using simulation.
Dynamic stabilization of hydrogen in an intense, high-frequency, pulsed laser field

We present calculations of ionization rates, trapping probabilities, and electron densities for a three-dimensional hydrogen atom in an intense, high-frequency, pulsed laser field. Under certain conditions, we find that hydrogen has a significant probability of surviving the ramp of the laser field to intensities at which ionization is strongly suppressed. We examine the dynamics of this process and discuss a method to observe it experimentally.
Stabilization of a one-dimensional short-range model atom in intense laser fields

The stabilization of atoms in the presence of very intense and short laser pulses has been proposed and confirmed in various numerical simulations (e.g. Su et al). A question was then raised by several authors (Chen and Bernstein, Krainov and Preobrazhenskii, and Geltman) concerning the possibility of producing such stabilization in a one-dimensional model atom with zero range of electron - nucleus interaction. In this paper we report evidence of stabilization through the suppression of ionization for such a model atom. We find that the use of a high-frequency laser pulse is necessary for such a realization.
Preoperative localization of parathyroid tissue with technetium-99m sestamibi 123I subtraction scanning.

To evaluate the utility of technetium-99m (Tc-99m) sestamibi for visualization of functioning parathyroid tissue, 14 subjects underwent Tc-99m sestamibi 123I subtraction scanning as part of the preoperative evaluation for hyperparathyroidism. Informative scans were obtained in 13 subjects, including 7 patients with recurrent or persistent hyperparathyroidism, and correctly identified the location of the hyperfunctioning parathyroid tissue found at surgery. In all informative patients, hyperparathyroidism was due to adenomatous disease or hyperplasia secondary to renal failure. Successful scans were obtained with glands as small as 220 mg. In the lone patient in whom Tc-99m sestamibi scanning failed to localize hyperfunctioning parathyroid tissue, surgery revealed a 1700-mg hyperplastic parathyroid neoplasm in the neck. In no case did a Tc-99m sestamibi scan suggest parathyroid tissue where there was none. In 1 case, a patient presented with persistent hyperparathyroidism after 1 neck and a second combined...
Mitochondria in the striatum of subjects with schizophrenia

AbstractObjectives. Schizophrenia is a severe mental illness that manifests pathology in many brain regions, including the striatum. Among the abnormalities in schizophrenia are those related to mitochondria. The present study sought to determine whether the number of mitochondria was affected at the level of the synapse. Methods. Human postmortem striatum from schizophrenia subjects and controls was examined at the ultrastructural level. The density of mitochondria and synapses were tabulated using stereology. Results. There were similar overall numbers of mitochondria in the caudate nucleus and putamen of schizophrenia subjects vs. controls, but a differential distribution of existing mitochondria. Schizophrenia subjects had 26–30% fewer mitochondria per synapse compared to controls. This may contribute to the pathophysiology of the illness, may be a medication effect, or an adaptive response to normalize the high number of striatal synapses we have previously found. The higher density of mitochondria i...
Robotic Utilization in Gastric Cancer Surgery

The robotic surgery platform has potential advantages over laparoscopy for gastrectomy with lymphadenectomy for cancer. Many surgeons in both the East and West feel that the wristed instrumentation, stable video platform, and three-dimensional view allow for more precise dissection around the mesenteric vessels than what can be achieved with standard laparoscopy. This advantage comes with significantly increased cost, however, and it is unclear whether it will translate into measureable clinical benefits for patients. The chapter discusses the technical steps of robotic-assisted gastrectomy and summarizes current literature regarding the learning curve, patient selection, outcomes, and cost.
Ultrastructure and growth of human limb mesenchyme (HLM15) in vitro.

Human embryonic hand and foot plates (horizon XVI) exhibit localized differences in mitotic activity between developing digital and interdigital zones of mesenchyme. To investigate development of regulation of cell reproduction, mesenchymal cells from lower limb buds dissected from a human embryo (stage XV) were cultured. Electron microscopy reveals that HLM15 cells in situ are fibroblastic, exhibit euchromatic nuclei, one to two peripheral nucleoli, extensive granular ER, free ribosomes, and microfilaments and microtubules oriented in the long axis of cellular processes. Cells released from substratum with trypsin-EDTA become rounded and microfilaments and microtubules become disoriented, perinuclear bundles. HLM15 has a mean generation time of 24 hours during logarithmic growth and karyotype analysis indicates that cells retain diploid chromosomal number after 17 passages. DNA-fluorochrome analysis on the Los Alamos Flow Microfluorometer (FMF) demonstrates that HLM15 cells possess no detectable polyploidy. Computer fit of FMF distributions reveal that random populations of HLM15 during exponential growth contain 42.6% cells in G1, 45.9% in S and 11.5% in G2+M. As confluency is reached these data become 57.6%, 37.5% and 4.9% respectively. Disaggregated limb mesenchyme (in vivo) analyzed without culturing exhibit FMF distributions of 56.1% in G1, 36.7% in S and 7.2% in G2+M. Similarities in cell cycles between near-confluent HLM15 cultures and limb mesenchyme in vivo suggest that regulation can be achieved by increasing or decreasing the traverse time through G1 (both in vitro and in vivo). The proportion of non-cycling cells (G0) in the FMF G1 distribution is presently not known.
On a natural homotopy between linear and nonlinear single-layer networks

In this paper we formulate a homotopy approach for solving for the weights of a network by smoothly transforming a linear single layer network into a nonlinear perceptron network. While other researchers have reported potentially useful numerical results based on heuristics related to this approach, the work presented here provides the first rigorous exposition of the deformation process. Results include a complete description of how the weights relate to the data space, a proof of the global convergence and validity of the method, and a rigorous formulation of the generalized orthogonality theorem to provide a geometric perspective of the solution process. This geometric interpretation clarifies conditions resulting in the appearance of local minima and infinite weights in network optimization procedures, and the similarities of and differences between optimizing the weights in a nonlinear network and optimizing the weights in a linear network. The results provide a strong theoretical foundation for quantifying performance bounds on finite neural networks and for constructing globally convergent optimization approaches on finite data sets.
Volcanic Hazards in the Pacific Northwest

The Cascade Range stretches from south-western British Columbia to northern California; the Range consists of major composite volcanic centres, most of which have been active during late Pleistocene and Holocene time. In addition, thousands of smaller basaltic or basaltic-andesite volcanoes have been active during the past few million years. Flow-age and tephra hazards associated with future eruptions of composite volcanoes in the Range will endanger communities located within about 50 km of erupting volcanoes. Significant effects will extend to still greater distances down wind from the volcanoes and along stream valleys that head at the volcanoes. Volcanic-hazard assessments and hazard-zonation maps developed for volcanoes in the Range can be used by authorities for long-range land-use planning and provide information to help mitigate the effects of future eruptions.
Solvent Effects on Chemical Processes, I: Solubility of Aromatic and Heterocyclic Compounds in Binary Aqueous—Organic Solvents

The standard free energy change (ΔG°) for equilibrium dissolution in binary solvent mixtures is written as a sum of effects arising from solvent—solvent interactions (the general medium effect), solvent—solute interactions (the solvation effect), and solute—solute interactions (the intersolute effect). The general medium effect is given by gAγ, where g is a curvature correction factor to the surface tension (γ) and A is the molecular cavity surface area. A new feature is the definition of γ to be that value appropriate to the equilibrium mean solvation shell composition. The solvation effect is modeled by stoichiometric stepwise competitive equilibria between the two solvent components for the solute. The intersolute effect includes the crystal energy and solution phase interactions. In this work, water was solvent component 1, and various miscible organic cosolvents served as solvent component 2. Relating all data to the fully aqueous solution gives an explicit expression for δMΔG°, the solvent effect on the free energy change, as a function of the mole fractions x1 and x2. This function is a binding isotherm. Nonlinear regression leads (for a two‐step solvation scheme) to estimates of the solvation exchange constants K1, and K2 and the parameter gA. This relationship was applied to 44 systems comprising combinations of 31 solutes and eight organic cosolvents. Curve fits were good to excellent, and most of the parameter estimates had physically reasonable magnitudes.
Guarding Sensitive Information Streams through the Jungle of Composite Web Services

Complex and dynamic web service compositions may introduce unpredictable and unintentional sharing of security-sensitive data (e.g., credit card numbers) as well as unexpected vulnerabilities that cause information leak. This paper describes a fine-grain access policy specification of security-sensitive data items for each component web service. We propose the SF-Guard architecture to enforce these access policies at component web services. A prototype implementation of SF-Guard (on Apache Axis2) and its evaluation show that effective protection of security-sensitive information can be achieved at low overhead (a few percent addition to response time) while preserving the functionality of flexible web service composition.
Pop-up threat models for persistent area denial

Pop-up threats usually appear or disappear randomly in a battle field. If the next pop-up threat locations could be predicted it would assist a search or attack team, such as in a persistent area denial (PAD) mission, in getting a team of unmanned air vehicles (UAVs) to the threats sooner. We present a Markov model for predicting pop-up ground threats in military operations. We first introduce a general Markov chain of order n to capture the dependence of the appearance of pop-up threats at previous locations of the pop-up threats over time. We then present an adaptive approach to estimate the stationary transition probabilities of the nth order Markov models. To choose the order of the Markov chain model for a specific application, we suggest using hypothesis tests from statistical inference on historical data of pop-up threat locations. Anticipating intelligent responses from an adversary, which might change its pop-up threat deployment strategy upon observing UAV movements, we present adaptive Markov chain models using a moving horizon approach to estimate possibly abrupt changes in transition probabilities. We combine predicted and actual pop-up target locations to develop efficient cooperative strategies for networked UAVs. A theoretical analysis and simulation results are presented to evaluate the Markov model used for predicting pop-up threats. These results demonstrate the effectiveness of cooperative strategies using the combined information of threats and predicted threats in improving overall mission performance.
Structure-activity relationships involving the catechol subunit of rolipram

Abstract Structure-activity relationships involving the aromatic ring of the selective PDE IV inhibitor, rolipram (1), are discussed.