cssi/SciSciGPT-SciSciNet huggingface dataset:
Simultaneous all-optical packet manipulation and wavelength shifting in a reconfigurable WDM network

Wavelength shifting will potentially be important in future high-capacity, packet-switched, wavelength-division-multiplexed (WDM) networks. Wavelength shifting, which transfers data from one wavelength to another, is important because it allows for (i) the system-wide re-use of wavelengths in a WDM network with more users than available wavelengths, and (ii) the reconfiguration of wavelength-specific paths in a dynamic network when changing traffic patterns require data-packet rerouting at a switching node. In order to maintain high throughput, a dynamically reconfigurable WDM network may require all-optical manipulation of a transmitted Gbit/s data packet in addition to wavelength shifting. We will discuss the simultaneous operation of all-optical wavelength shifting with: (i) packet header replacement, and (ii) data format conversion.
A video-based technique for measuring ankle-subtalar motion during stance.

Abstract This study was designed to demonstrate that an accurate and reliable technique for measuring the rotational motion between rigid bodies can be developed from a video-based data collection system. Tests on the accuracy of the rotational measurements demonstrated that for each of five trials, under three test conditions, mean errors of less than 0.4° and standard deviations of less than 0.2° were found for all three joint axes. The reliability of the technique for evaluating ankle-subtalar motion during stance was also demonstrated, and the technique was then applied to evaluate ankle-subtalar motion during the stance phase of gait. The rotational motion of the combined ankle-subtalar joint was characterized by complexity and inter-subject variability. Two simplified models previously used to describe ankle-subtalar motion were tested using the current data and were proven to be inadequate for describing ankle-subtalar motion during stance.
Digestive system disorders: gastroesophageal reflux disease.

This article comes from Clinical Evidence (1999; 1 : 145-153), a new resource for clinicians produced jointly by the BMJ Publishing Group and the American College of Physicians-American Society of Internal Medicine. Clinical Evidence is an extensively peer-reviewed publication that summarizes the best available evidence on the effects of common clinical interventions gleaned from thorough searches and appraisal of the world literature. It became available in the United States late last year. Please see advertisement for more information or, alternatively, visit the web site at www. evidence.org.
Quantum Chemistry Study of Fullerene and Carbon Nanotube Fluorination

The reaction of fullerenes and carbon nanotubes with molecular fluorine has been studied using B3LYP calculations. The nanotube substrates are represented by model polycyclic aromatic hydrocarbons that are constrained to have nonplanar geometries with curvatures corresponding to (10,10), (5,5), and (16,0) nanotubes. Most of the calculations for fullerenes are carried out for C60. The calculations are focused on the addition of one to four F-atoms to the fullerene or nanotube substrate. The preferred binding sites for sequential fluorine addition are studied along with the geometry deformations experienced by the substrate. For C60, a strong preference exists for pairwise addition to the C−C double bonds between pentagons (denoted 6/6 addition). Subsequent addition to neighboring 6/6 bonds is also favored. These results are in agreement with recent experimental data. For addition of F2 to armchair nanotubes, the favored product has the fluorine atoms bonded to adjacent carbons with an orientation perpendic...
Imaging standing waves in a two-dimensional electron gas

ELECTRONS occupying surface states on the close-packed surfaces of noble metals form a two-dimensional nearly free electron gas1–3. These states can be probed using the scanning tunnelling microscope (STM), providing a unique opportunity to study the local properties of electrons in low-dimensional systems4. Here we report the direct observation of standing-wave patterns in the local density of states of the Cu(lll) surface using the STM at low temperature. These spatial oscillations are quantum-mechanical interference patterns caused by scattering of the two-dimensional electron gas off step edges and point defects. Analysis of the spatial oscillations gives an independent measure of the surface state dispersion, as well as insight into the interaction between surface-state electrons and scattering sites on the surface.
Toxoplasma gondii Cathepsin L Is the Primary Target of the Invasion-inhibitory Compound Morpholinurea-leucyl-homophenyl-vinyl Sulfone Phenyl

The protozoan parasite Toxoplasma gondii relies on post-translational modification, including proteolysis, of proteins required for recognition and invasion of host cells. We have characterized the T. gondii cysteine protease cathepsin L (TgCPL), one of five cathepsins found in the T. gondii genome. We show that TgCPL is the primary target of the compound morpholinurea-leucyl-homophenyl-vinyl sulfone phenyl (LHVS), which was previously shown to inhibit parasite invasion by blocking the release of invasion proteins from microneme secretory organelles. As shown by fluorescently labeled LHVS and TgCPL-specific antibodies, TgCPL is associated with a discrete vesicular structure in the apical region of extracellular parasites but is found in multiple puncta throughout the cytoplasm of intracellular replicating parasites. LHVS fails to label cells lacking TgCPL due to targeted disruption of the TgCPL gene in two different parasite strains. We present a structural model for the inhibition of TgCPL by LHVS based on a 2.0 A resolution crystal structure of TgCPL in complex with its propeptide. We discuss possible roles for TgCPL as a protease involved in the degradation or limited proteolysis of parasite proteins involved in invasion.
Žižek's Balkans: Geopolitical fractures in Žižek's universalism

This introduction to a special section on Slavoj Žižek suggests that to understand his philosophy, activism, and psychoanalysis we must consider his relation to the Balkan context from which his work emerges and with which it continues to be engaged.
Pharmacokinetic interactions of tolazamide and oxyphenbutazone in dogs.

The described pharmacokinetic analysis involved two separate studies on nine dogs randomly assigned to three groups of three dogs each. In the first study, the effect of varying the dosage of tolazamide was examined. The second study concerned the effect of varying the dosage of oxyphenbutazone on tolazamide. A 3 × 3 Latin square was used to study both effects. Each group received each treatment, with a minimum of 1 week separating each session. The pharmacokinetics of tolazamide followed a two-compartment open model. The hybrid rate constants, α and β, were not significantly different at the three dosages when measured by a three-way analysis of variance. The only significant difference at the three dosage levels of tolazamide was in the apparent volume of distribution. In the pharmacokinetic interaction associated with intravenous administration of one dose of tolazamide and three doses of oxyphenbutazone, the apparent volume of distribution and the hybrid rate constant α did not change significantly while the hybrid rate constant for tolazamide, β, seemed to decrease with increasing oxyphenbutazone.
Cluster synthesis 37—Platinum-ruthenium carbido-cluster complexes: The syntheses and structural characterizations of PtRu5(C)(CO)16, Pt2Ru5(C)(CO)13(COD)2, and Pt3Ru5(C)(CO)14(COD)2

From the reaction of [Ru5(C)(CO)14]2− with Pt(COD)Cl2, COD=1, 5 cyclooctadiene, the new platinum-ruthenium carbido cluster complex PtRu5 (C)(CO)14(COD),1, was obtained in 41% yield. When1 was allowed to react with carbon monoxide (25°C/1 atm), the new complex PtRu5(C)(CO)16,2, was obtained almost quantitatively (97% yield). Compound2 was characterized by IR and single-crystal X-ray diffraction analysis. The six metal atoms are arranged in the form of an octahedron with the carbide ligand located in the center. Compound1 is believed to have a similar structure to2 except for a COD ligand coordinated to the platinum atom. When activated by treatment with Me3NO, compound2 reacts with Pt(COD)2 at 25°C to yield two higher nuclearity cluster complexes, Pt2Ru5C(CO)13(COD)2.3, and Pt3Ru5C(CO)14(COD)2,4. The structure of3 is similar to that of1, but contains a Pt(COD) grouping capping one Ru3 triangle of the PtRu5 octahedron. The structure of4 consists of a PtRu5 octahedron with two Pt(COD) capping groups, one on an Ru3 triangle and the other on a PtRu2 triangle of the octahedron. Crystal data: for2, space group=P21/n,a=9.341 (2) A,b=14.957 (3) A,c=36.80 (1) A, β=90.38 (2) °,Z=8, 4034 reflections,R=0.030, for3, space group=P21/c,a=14.998 (3) A,b=10.288 (3) A,c=26.581 (7) A, β=102.75 (2) °,Z=4, 2917 reflections,R=0.028. for4, space group=P21/n,a=13.412 (4) A,b=16.252 (4) A,c=20.107 (4) A, β=106.13 (2) °,Z=4, 2745 reflections,R=0.032.
Condensation of DNA in situ in metaphase chromosomes induced by intercalating ligands and its relationship to chromosome banding.

Interactions of certain intercalating cationic ligands with nucleic acids result in the formation of products that undergo condensation and agglomeration; this transition in solution can be monitored by light-scatter measurements. In the present study, using such intercalators as the antitumor drug mitoxantrone or fluorochromes acridine orange and quinacrine, we induced condensation of DNA in situ in Chinese hamster chromosomes. The in situ products scattered light and could be detected by darkfield- or phase-contrast microscopy. In the darkfield the complexes had a characteristic granular appearance and often generated a banding pattern on the chromosomes. In contrast, condensation of DNA in situ by the nonintercalating polyvalent cations (Co3+, spermine4+), while enhancing the chromosome's image contrast, did not produce the granular products or the banding. The condensation of free DNA, single or double stranded, natural or synthetic, the later of various base composition and configuration, was also measured in solution. The condensation in solution and in situ was observed at similar concentrations of the respective ligands. The intercalating dye ethidium bromide, which did not condense DNA in solutions of moderate and high ionic strength, also did not generate the granular products or banding on chromosomes. The data also show that both base composition and configuration are important factors in determining the sensitivity of DNA to condensation by particular intercalating ligands. The studies suggest that the phenomenon of DNA condensation by intercalating dyes, which shows a high degree of specificity with respect to primary and secondary structures of DNA, may be associated with mechanisms of chromosome banding induced by the intercalating thiazine dyes in Giemsa staining or by quinacrine. Observation of chromosome banding based on light-scatter detection in darkfield microscopy allows the study of interactions between DNA and the ligands that neither fluoresce nor generate colored products. This principle of chromosome “counter-staining” can be explored by flow cytometry.
Mechanism of action of chromogranin A on catecholamine release: molecular modeling of the catestatin region reveals a β-strand/loop/β-strand structure secured by hydrophobic interactions and predictive of activity

Abstract A novel fragment of chromogranin A, known as `catestatin' (bovine chromogranin A 344–364 ), inhibits catecholamine release from chromaffin cells and noradrenergic neurons by acting as a non-competitive nicotinic cholinergic antagonist, and may therefore constitute an endogenous autocrine feedback regulator of sympathoadrenal activity. To characterize how this activity depends on the peptide's structure, we searched for common 3-dimensional motifs for this primary structure or its homologs. Catestatin's primary structure bore significant (29–35.5% identity, general alignment score 44–57) sequence homology to fragment sequences within three homologs of known 3-dimensional structures, based on solved X-ray crystals: 8FAB, 1PKM, and 2IG2. Each of these sequences exists in nature as a β-strand/loop/β-strand structure, stabilized by hydrophobic interactions between the β-strands. The catestatin structure was stable during molecular dynamics simulations. The catestatin loop contains three Arg residues, whose electropositive side chains form the terminus of the structure, and give rise to substantial uncompensated charge asymmetry in the molecule. A hydrophobic moment plot revealed that catestatin is the only segment of chromogranin A predicted to contain amphiphilic β-strand. Circular dichroism in the far ultraviolet showed substantial (63%) β-sheet structure, especially in a hydrophobic environment. Alanine-substitution mutants of catestatin established a crucial role for the three central arginine residues in the loop (Arg 351 , Arg 353 , and Arg 358 ), though not for two arginine residues in the strand region toward the amino-terminus. [ 125 I]Catestatin bound to Torpedo membranes at a site other than the nicotinic agonist binding site. When the catestatin structure was `docked' with the extracellular domain of the Torpedo nicotinic cholinergic receptor, it interacted principally with the β and δ subunits, in a relatively hydrophobic region of the cation pore extracellular orifice, and the complex of ligand and receptor largely occluded the cation pore, providing a structural basis for the non-competitive nicotinic cholinergic antagonist properties of the peptide. We conclude that a homology model of catestatin correctly predicts actual features of the peptide, both physical and biological. The model suggests particular spatial and charge features of the peptide which may serve as starting points in the development of non-peptide mimetics of this endogenous nicotinic cholinergic antagonist.
A Chronic Model for Investigation of Experimental: Spinal Anesthesia in the Dog

A chronic model for investigation of spinal anesthesia in the dog is described. This model incorporates the use of a chronically implanted catheter in the lumbar subarachnoid space. An 18-gauge thin-walled Crawford needle is passes percutaneously into the subarachnoid space. An 18-gauge epidural catheter is then threaded through the needle into the subarachnoid space and the distal end attached to a special metal valve which is sutured under the skin. One-milliliter volumes of various local anesthetic solutions were injected intrathecally via the valve and catheter. Durations of the effects of the local anesthetics were evaluated. Duration which hind-limb paralysis persisted in the dog. The times to onset and durations of motor blockades were evaluated following the intrathecal injection of dibucaine, tetracaine, lidocaine, bupivacaine, chloroprocaine, and mepivacaine. Times to onset ranged from 1.1 to 2.3 min. Durations of motor blockade were longest for dibucaine and tetracaine, followed in order of decreasing duration by bupivacaine, lidocaine, chloroprocaine, and mepivacaine. The durations of subarachnoid conduction motor blockades in the dog are qualitatively similar to reported values for spinal anesthesia in man. Therefore, the technique described may provide a useful model to evaluate factors that may influence spinal anesthesia.
Surf and turf: mechanism of enhanced virus spread during poxvirus infection.

Commentary on Doceul, V.; Hollinshead, M.; van der Linden, L.; Smith, G.L. Repulsion of superinfecting virions: a mechanism for rapid virus spread. Science 2010, 327, 873–876.
Free standing: social control and the sane epileptic, 1850-1950

In 1950, Maurice Walsh 1 proposed that certain medical terms created a tyranny over individuals who were diagnosed as having the conditions they named. These diagnoses evoked an immediate and a negative response from the public. Among these terms was epilepsy. Throughout history, their often bizarre and misunderstood seizure-related behaviors resulted in people with epilepsy being described as possessed by demons, mystic, insane, degenerate, and defective. Even after epilepsy was determined to be a neurological disorder, its stigma persisted, and numerous attempts were made to segregate people with epilepsy from society. One means society used to segregate or remove any unwanted segment of the population from everyday life was to impose social controls on them.2 Societal-endorsed methods of control of people with epilepsy were particularly oppressive from 1850 to 1950. Among the methods used to segregate them from society were commitment to asylums for the insane, restriction from education and employment, and suppression by social and eugenic laws. Response to this repression came from pioneering physicians who, during this same period, undertook groundbreaking research into the causes and treatment of seizures. Together with a number of enlightened philanthropists, these physicians created and supported innovative care at residential colonies for people with epilepsy. These colonies provided a caring refuge offering expert medical care, education, employment, and support, which allowed many people with epilepsy to return to society as productive members.
Local Heat Transfer Coefficients of Laboratory Facial Protective Systems in Wind

This paper describes a laboratory experiment which determined the local heat transfer coefficients from a nonuniformly insulated cylinder in wind. Application of these data to the problem of facial cooling in wind is discussed. It is shown that the quantitative data obtained are comparable to the beliefs based on qualitative human experience.
Pseudouremic Pruritus: A Scabies Epidemic in a Dialysis Unit

Abstract A scabies epidemic was studied in a university hospital dialysis unit. Itching in patients was initially attributed to uremic pruritus, and diagnosis of the epidemic was delayed until cases occurred among the staff. Sixteen cases (seven patients and nine staff) were identified by survey questionnaire and dermatologic examination. Application of 1 % lindane lotion (Kwell, Reed and Carnrick, Piscataway, NJ) to all patients dialyzed in the unit and the entire staff eradicated the epidemic. A dialysis unit-associated nosocomial scabies epidemic has not been reported before and may mimic uremic pruritus in dialysis patients.
Hydrologic Trends and Correlations in South Texas River Basins: 1950-2009

AbstractThe identification of seasonal and annual trends in precipitation and streamflow volumes at the regional scale contributes to the understanding of global climate change and variation and is essential to the development of hydrologic models, hydrologic forecasting, and water resources planning and management for basins. This study examines such trends over the past 60 years (1950–2009) for the Nueces River basin, the San Antonio River basin, and the Guadalupe River basin, all in south Texas. The correlation of precipitation and streamflow with the El Nino Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) climatic indices is also evaluated, with a view toward incorporating these two relatively predictable cyclical patterns into modeling and forecasting of precipitation and streamflow. Trends and correlations were measured using the Kendall and Mann-Kendall test statistics, while the more commonly used Pearson r coefficient was shown not to be consistently appropriate for the data...
Categories and context in scalable execution visualization

Abstract To understand the behavior of processors in a large-scale asynchronous execution, we must often consider the global execution context in which each processor is immersed. Global context is best described by scalable execution views that do not change in format, size, meaning, or clarity as processors are added to an execution. One way to produce a scalable view is to categorize processors by behavior and display category statistics. Categorical views are particularly useful when there is an inverse mapping from an arbitrary view region to the subset of processors whose behavior was described in the region. Then the user can define new categories graphically by specifying subregions of views, using graphical attributes such as color and texture to depict category membership. The execution visualization tool Seeplex implements this form of category management to provide scalable execution views.
Clinical investigation of ethoheptazine citrate and acetylsalicylic acid as a postoperative analgesic in oral surgery

Abstract As far as the postoperative pain-relieving qualities of ethoheptazine citrate with acetylsalicylic acid and codeine and acetylsalicylic acid examined in this study are concerned, there was no appreciable difference. It was found that two ethoheptazine citrate and acetylsalicylic acid tablets compared favorably with one codeine and acetylsalicylic acid tablet for the relief of postoperative pain from oral surgical procedures in the dosages used in this investigation. There were very few side effects from ethoheptazine citrate and acetylsalicylic acid as compared to codeine and acetylsalicylic acid. Ethoheptazine citrate in combination with acetylsalicylic acid (Zactirin) appears to be an excellent nonnarcotic analgesic for the relief of postoperative pain from dental oral surgical procedures for the ambulatory patient in a pain range from moderate to moderately severe.
Talin dynamics in living microinjected nonmuscle cells

To investigate the role of talin in the anchoring of actin-containing stress fibers to the cell membrane of nonmuscle cells, a fluorescent analog of the adhesion plaque protein talin was developed, characterized, and microinjected into living cells. Purified chicken gizzard talin was covalently labeled with the fluorescent dye lissamine rhodamine B sulfonyl chloride. The fluorescently labeled protein was then chromatographed on Sephadex G-25 and DEAE-cellulose in order to remove free dye and denatured protein. The fluorescent talin was able to bind purified vinculin and was localized in adhesion plaques, membrane ruffles, microspikes, and polygonal networks in acetone-permeabilized nonmuscle cells. In cells that were double-stained with fluorescent talin and an affinity-purified anti-talin antibody, a one-to-one correspondence of adhesion plaque staining was seen. Living epithelial cells (PtK2) were microinjected during interphase with fluorescent talin. Computer-enhanced video microscopy was used to document adhesion plaque dynamics such as 1) changes in plaque shape, 2) alterations in plaque positions, and 3) the appearance, growth, and dissolution of plaques. In cells that were followed during mitosis, the adhesion plaques disappeared during cell rounding and then subsequently reappeared upon spreading of the two daughter cells. Treatment of microinjected cells with DMSO in order to disassemble stress fibers resulted in an altered localization of the fluorescent talin. Upon recovery of the cell from the drug, the talin was visualized in its characteristic submembraneous position. These results are the first to document the role and distribution of talin in dynamic processes occurring in living microinjected nonmuscle cells.
Shape-preserving properties of univariate cubic L 1 splines

The results in this paper quantify the ability of cubic L2 splines to preserve the shape of nonparametric data. The data under consideration include multiscale data, that is, data with abrupt changes in spacing and magnitude. A simplified dual-to-primal transformation for a geometric programming model for cubic L1 splines is developed. This transformation allows one to establish in a transparent manner relationships between the shape-preserving properties of a cubic L1 spline and the solution of the dual geometric-programming problem. Properties that have often been associated with shape preservation in the past include preservation of linearity and convexity/concavity. Under various circumstances, cubic L1 splines preserve linearity and convexity/concavity of data. When four consecutive data points lie on a straight line, the cubic L1 spline is linear in the interval between the second and third data points. Cubic L1 splines of convex/concave data preserve convexity/concavity if the first divided differences of the data do not increase/decrease too rapidly. When cubic L2 splines do not preserve convexity/concavity, they still do not cross the piecewise linear interpolant and, therefore, they do not have extraneous oscillation.
MicroRNA-608 and microRNA-34a regulate chordoma malignancy by targeting EGFR, Bcl-xL and MET.

Chordomas are rare malignant tumors that originate from the notochord remnants and occur in the skull base, spine and sacrum. Due to a very limited understanding of the molecular pathogenesis of chordoma, there are no adjuvant and molecular therapies besides surgical resection and radiation therapy. microRNAs (miRNAs) are small noncoding regulatory RNA molecules with critical roles in cancer. The role of miRNAs in chordomas is mostly unknown. We uncover microRNA-608 (miR-608) and microRNA-34a (miR-34a) as novel tumor suppressive microRNAs that regulate malignancy in chordoma. We find that miR-608 and miR-34a expressions are downregulated in human chordoma cell lines and primary cells at least partially via alteration of their genes’ copy numbers. We identify the commonly deregulated oncogenes EGFR and Bcl-xL as direct targets of miR-608 and the receptor tyrosine kinase MET as direct target of miR-34a. We show that EGFR and MET activations promote chordoma cell proliferation and invasion and that pharmacological inhibition of EGFR and MET inhibits chordoma cell proliferation and survival. We demonstrate that restoration of miR-608 and miR-34a inhibits cell proliferation and invasion and induces apoptosis in chordoma cells. We find that miR-34a inversely correlates with MET expression and miR-608 inversely correlates with EGFR expression in chordoma cells. These findings demonstrate for the first time that miR-608 and miR-34a regulate chordoma malignancy by regulating EGFR, MET and Bcl-xL.
Synthesis, characterization, and properties of tethered polystyrene-b-polyacrylate brushes on flat silicate substrates

Surface-immobilized polystyrene-b-polyacrylate brushes have been synthesized on silicate substrates from chlorine-terminated polystyrene (PS) brushes by atom transfer radical polymerization (ATRP). ATRP of methyl methacrylate (MMA), methyl acrylate (MA), and (N,N-dimethylamino)ethyl methacrylate (DMAEMA) produced tethered diblock copolymer brushes, which were characterized by ellipsometry, FTIR-ATR, tensiometry, and XPS. “Control” polymerizations supported a radical mechanism for the MMA polymerization. The thickness of the polyacrylate terminal block was controlled by free initiator concentration. All three diblock copolymer brushes underwent self-reorganization and exhibited different surface properties in response to different solvent treatments. For PS-b-PMMA and PS-b-PMA brushes, treatment with CH2Cl2 resulted in localization of PMMA and PMA at the air interface; treatment with cyclohexane localized the PS block at the air interface. PS-b-PDMAEMA brushes exhibited a similar behavior using cyclohexane...
Cytomegalovirus infection and non-neutropenic fever after autologous stem cell transplantation : high rates of reactivation in patients with multiple myeloma and lymphoma

In a retrospective study, we examined the association between cytomegalovirus (CMV) infection and non-neutropenic fever immediately following autologous peripheral blood stem cell transplantation for a variety of haematological malignancies and solid tumours. Sixty non-neutropenic febrile episodes (41 in CMV-seropositive and 19 in CMV-seronegative patients) were evaluated. CMV reactivation, documented by CMV antigenaemia, was detected in 16 out of 41 (39%) seropositive patients compared with 0 out of 19 seronegative patients. In 12 of these 16 patients, CMV infection was considered the sole cause of fever. Thirteen patients had maximum antigenaemia levels > 5 cells/slide. Specific antiviral treatment led to the resolution of the fever in all, but two, patients, who developed fatal CMV pneumonia. Patients with multiple myeloma and lymphoma, possibly owing to a combination of disease-related characteristics and prior immunosuppressive treatment, had high rates of CMV reactivation and may require more frequent diagnostic evaluation and prompt therapeutic intervention.
Role of tactual-kinesthetic feedback in transfer of perceptual learning for rats with pigmented irises.

Hooded rats were pre-exposed to circles and triangles in an otherwise visually sparse environment where opportunity to manipulate the forms was varied for the early experience groups. Although early experience with these stimuli enhanced their later discriminability over that shown by control animals who received no early experience, opportunity to manipulate the forms produced no additional gain in perceptual learning relative to Ss not allowed to manipulate the pre-exposed shapes. The findings restrict the generality of the tactual-kinesthetic feedback hypothesis.
Isolation of the periplasm of Neisseria gonorrhoeae

Summary The periplasm of Neisseria gonorrhoeae should be similar to other Gram-negative bacteria, but no published reports confirm this assumption. We used a periplasmic isolation procedure developed in Escherichia coli to release the periplasmic contents of N. gonorrhoeae. The resultant periplasmic extract lacked lipopolysaccharide, protein markers of inner or outer membranes, surface-radiolabelled protein components, or ribosomal proteins. The periplasmic extract contained a single haem protein believed to be a c-type cytochrome known to exist in the periplasm of other Gram-negative species, and retained significant alkaline phosphatase activity. The dominant protein species released in the periplasmic extract was the gonococcal homologue of elongation factor Tu, a major component released in similar periplasmic extracts of E. coli. These data showed that the extraction procedure selectively released periplasmic components and that the gonococcal periplasm was comparable to that of E. coli. Further analysis of the gonococcal periplasm may provide important insights into the physiology of this pathogen of humans.
Sb induced nucleation of InSb on (III) InSb substrates by molecular beam epitaxy

Hillock formation was observed on (III) InSb grown by molecular beam epitaxy. The hillocks covered layers were examined by X-ray diffraction, Auger spectroscopy and ion channeling measurements and found to be of single phase growth and perfectly oriented with the substrates. The growth conditions to avoid the hillock formation were investigated and a model for the hillock formation is proposed. A growth rate hierarchy was determined from the shapes of the faceted hillocks.
Suppression of plasminogen activator inhibitor-1 release from human cerebral endothelium by plasminogen activators. A factor potentially predisposing to intracranial bleeding.

Background Intracranial bleeding is the most catastrophic potential complication of treatment with thrombolytic agents. To identify potential factors that may contribute to this problem, we characterized elaboration by human brain endothelial cells of plasminogen activator inhibitor-1 (PAI-1) and measured PAI-1 mRNA levels. Methods and Results When human cerebral microvascular endothelial cells (HCMEC), pial arterial endothelial cells, and middle meningeal arterial endothelial cells were exposed to 10 to 1000 ng/mL recombinant tissue-type plasminogen activator (RTPA), urokinase-type plasminogen activator (UPA), or streptokinase/plasminogen (37 U streptokinase plus 2 μmol/L plasminogen) for 24 hours, they exhibited concentration-dependent decreases in elaboration of PAI-1 of 65±3%, 48±3%, and 59±8%. UPA and streptokinase/plasminogen elicited decreases of 33±8% and 35±4%, respectively, that were specific with respect to the protease agonists as to total protein synthesis and cell type; ie, neither human umb...
A simplified approach to degenerative disease: triangular resections of the mitral valve.

Background Only 40% of patients with mitral valve (MV) regurgitation undergo operative repair rather than replacement. Quadrangular resection combined with ring annuloplasty has been the most common method of repair for degenerative posterior leaflet disease. Techniques such as sliding annuloplasty and artificial chord usage have increased the complexity of repair. These techniques have been perceived to be difficult and have possibly reduced the incidence of MV repair. We present our experience with a simplified approach to MV repair utilizing a triangular resection and larger rings. Methods Retrospective review of all MV repairs over a 7-year period (1999 to 2006) revealed 154 patients who underwent triangular resection for degenerative disease. Patients who underwent ring annuloplasty without leaflet resection and patients who had artificial chords or quadrangular resections were excluded. Results Of 154 patients who underwent triangular resection, isolated posterior leaflet resection was performed on 130 patients. Isolated anterior and combined anterior and posterior leaflet triangular resections were performed on 16 and 8 patients, respectively. Thirty-day postoperative mortality was 0%. Five-year freedom from reoperation for recurrent mitral regurgitation was 99.0%. No patients who had intended leaflet resection were converted to MV replacement. Intraoperative transesophageal echocardiogram revealed trace to 1+ mitral regurgitation. Mild systolic anterior motion was noted in 7.1% of cases initially, but resolved with volume loading in all. Conclusions Triangular leaflet resection of the mitral valve produces durable results and can be safely and efficiently performed with minimal morbidity and mortality. This technique should allow increased utilization of MV repair for degenerative disease.
Economic Impacts of the ShakeOut Scenario

For the ShakeOut Earthquake Scenario, we estimate $68 billion in direct and indirect business interruption (BI) and $11 billion in related costs in addition to the $113 billion in property damage i...
Evidence that glucose and sucrose uptake in oral streptococcal bacteria involves independent phosphotransferase and proton-motive force-mediated mechanisms

Sugar transport and glycolysis in Streptococcus sanguis NCTC 7865, Streptococcus mitis ATCC 903, Streptococcus salivarius NCTC 8606 and several strains of Streptococcus mutans were investigated by following the rate of acid production by washed bacteria at a constant pH of 7.0. The phosphoenolpyruvate-phosphotransferase system (PTS) was inhibited by low concentrations of chlorhexidine. When this PTS-inhibitory concentration of chlorhexidine was added to cells washed and re-suspended in KCl, glucose uptake and glycolysis continued at a greatly-reduced rate. Chlorhexidine abolished glucose and sucrose uptake and metabolism in bacteria washed and incubated in saline. The Na+-inhibition was reproduced in KCl-washed bacteria using the cyclic peptide ionophores, valinomycin and gramicidin, to dissipate K+ and H+ gradients across the cell membrane. Glucose metabolism by Strep. mutans B13 was more resistant to chlorhexidine than that of Strep. mutans NCTC 10449 or Strep. sanguis but was more sensitive to the ionophores. Valinomycin had a greater inhibitory effect on strain B13 than the other two. That ion gradients are important in the chlorhexidine-resistant glucose-uptake mechanism was confirmed using the classical uncoupling agents, carbonylcyanide-m-chlorophenylhydrazone, 2,4-dinitrophenol and KSCN. Glucose metabolism was inhibited in the presence of both the uncouplers and the PTS-inhibitory concentration of chlorhexidine and significant inhibition was also observed in the absence of the PTS inhibitor. Lactate or the ATPase inhibitor, dicyclohexyl carbodiimide (DCCD), had similar inhibitory effects on the non-PTS uptake system.(ABSTRACT TRUNCATED AT 250 WORDS)
Changes in the frequency of YM versus IIIM in the housefly, Musca domestica L., under field and laboratory conditions.

Summary In the housefly, Musca domestica L., sex is usually determined by a dominant factor, M, located on the Y chromosome. However, there are ‘autosomal male ’ (A M ) populations in which the M factor is located on one or more of the five autosomes (I–V) or on X. We examined changes in the frequency of A M and Y M males in North Carolina populations of houseflies after 4 years in the laboratory (NC Lab 02:06) and after 4 or 5 years in the field (NC 2006 and NC 2007). In 2002, 77 . 7 % of the male houseflies were III/III ;XY M , 20 % were III M /III ;XX, and 2 . 3 % were III M /III;XY M . After 4 years in the laboratory, III M /III males disappeared and 17 . 4 % of the males were X M Y M . Conversely, 4 years later, the field population was relatively unchanged from 2002. Thus, there was a strong selection against III M /III males in the laboratory, but not in the field. Field-collected flies from 2007 indicated a slight increase in the frequency of XY M males and a slight decrease in the frequency of III M /III males (relative to 2002 and 2006), suggesting that the relative frequency of XY M and III M /III can vary slightly over time in field populations. The detection of X M Y M males in 2007 offered the opportunity to evaluate the frequency of the female-determining F D factor, which was found to be present in both the laboratory and field populations, but frequencies varied greatly. The present study represents the first report of F D in houseflies from North America. The significance of these results, relative to observed clines in A M versus Y M males, is discussed.
Spectral sensitivities of color receptors in the compound eye of the cockroach Periplaneta

Intracellular recording from single retinular cells of a white eye mutant of the cockroach Periplaneta americana stimulated between 316 and 704 nm reveals the presence of two classes of cells. In the dorsal part of the eye they are present in approximately equal numbers. Both have resting potentials of about 40 mv; neither responds with spikes. Ultraviolet receptors are maximally responsive at 365 nm (λmax); sensitivity falls steadily at longer wavelengths and is down two log units at 440 nm. The membrane responses of ultraviolet receptors usually consist of a large graded transient which can completely depolarize the cell, followed by a smaller and slower plateau of depolarization which lasts as long as the stimulus. Green receptors have λmax at about 507 nm. A tail of sensitivity extends through the violet and near ultraviolet, but sensitivity falls steadily to the long wavelength side of the λmax, and is down two log units at 615 nm. The membrane responses typically consist of a graded transient and lack the later plateau.
Parameter Characterization of Muscle Contraction Based on Myosin-Actin Interactions

A simple description of myosin-actin interactions is presented. Four parameters are defined: the probability, time, and energy of a myosin reaction, and a compression factor describing other muscle properties. The dependence of muscle tension upon contraction rate, derived from this model, is shown to agree with previous experimental data of Hill.
The vascular niche: home for normal and malignant hematopoietic stem cells.

Hematopoietic stem cells (HSCs) are uniquely capable of self-renewal and provision of all of the mature elements of the blood and immune system throughout the lifetime of an individual. HSC self-renewal is regulated by both intrinsic mechanisms and extrinsic signals mediated via specialized microenvironments or ‘niches’ wherein HSCs reside. HSCs have been shown to reside in close association with bone marrow (BM) osteoblasts in the endosteal niche and also in proximity to BM sinusoidal vessels. An unresolved question surrounds whether the endosteal and vascular niches provide synchronous or redundant regulation of HSC fate or whether these niches provide wholly unique regulatory functions. Furthermore, while some aspects of the mechanisms through which osteoblasts regulate HSC fate have been defined, the mechanisms through which the vascular niche regulates HSC fate remain obscure. Here, we summarize the anatomic and functional basis supporting the concept of an HSC vascular niche as well as the precise function of endothelial cells, perivascular cells and stromal cells within the niche in regulating HSC fate. Lastly, we will highlight the role of the vascular niche in regulating leukemic stem cell fate in vivo.
Micro-Scale Structures and Nano-Scale Materials for Chemical and Biological Sensors

Semiconductor and other materials with dimensions on the scale of micrometers or nanometers are being made into chemical and biological sensors. Besides being small, such devices are highly capable, low power and relatively inexpensive. They have many applications in personal health and safety, and for control of industrial processes.
What's so feminist about garters and bustiers? Neo-burlesque as post-feminist sexual liberation

The performance art of burlesque is gaining popularity in North American culture, but with many ‘neo-burlesque’ performers, critical reflection or commentary on the politics of female sexuality is glaringly absent or summarily dismissed. Neo-burlesque could be a feminist rewriting and reclaiming of a Western dance form, which showcased women simpering sexily for her audience. However, in order for neo-burlesque to have a feminist tone, it needs to do more than incorporate women of various ethnicities and body types to transcend patriarchal scripts of female sexuality. Some neo-burlesque includes disruptions of traditional scripts regarding female sexuality that demand the audience think about the complexities of desire, sexuality, and identity, often through a feminist lens. However, these critiques often do not go far enough in their interrogation of power structures and the politics of sexuality. This article makes the argument that the popularity of neo-burlesque in mainstream culture serves to oppress...
Role Modeling: An Opportunity for the Health Education Specialist

It is the responsibility of the profession to determine what is right, reasonable, and ethical health education practice. Opportunities within the profession abound to deliberate about the responsibility of health education specialists to role model positive health behaviors. Davis summarized the espoused perspectives nicely: We owe it to our profession and to our students to personally travel as far on the wellness continuum as behavioral choices will permit.... Health educators do have a special responsibility to be positive health role models by fulfilling their health potential and modeling the healthiest behaviors of which they are capable. All health educators need to accept for themselves the responsibilities that we assign to others.
Ultrasonic/sonic driller/corer as a hammer-rotary drill

Rock, soil, and ice penetration by coring, drilling or abrading is of great importance for a large number of space and earth applications. Proven techniques to sample Mars subsurface will be critical for future NASA astrobiology missions that will search for past and present life on the planet. The Ultrasonic/Sonic Drill/Corer (USDC) has been developed as an adaptable tool for many of these applications [Bar-Cohen et al., 2001]. The USDC uses a novel drive mechanism to transform the ultrasonic or sonic vibrations of the tip of a horn into a sonic hammering of a drill bit through an intermediate free-flying mass. For shallow drilling the cuttings travel outside the hole due to acoustic vibrations of the bit. Various methods to enhance the drilling/coring depth of this device have been considered including pneumatic [Badescu et al., 2006] and bit rotation [Chang et al., 2006]. The combination of bit rotation at low speed for cuttings removal and bit hammering at sonic frequencies are described in this paper. The theoretical background and testing results are presented.
Preparation of molybdenum(II) η2-vinyl complexes via sequential CCl activation and alkyne insertion

Abstract Reaction of the Schiff base ligand 1, prepared by the condensation of 2-chlorobenzaldehyde and N,N-dimethylethylenediamine with (η6-C6H5CH3)Mo(CO)3 2 resulted in the formation of the seven-coordinate molybdenum(II) metallacycle, 3, by oxidative addition of the strong aromatic CCl bond at molybdenum(0). The metallacycle 3 undergoes migratory insertion with electron-deficient internal acetylenes to afford novel η2-vinyl complexes 4, resulting in net replacement of a CCl bond by a CC bond.
Multidimensional Self-Perception of Sexually Abused Girls: Factor Models and Differences Between Sexual Abuse and Comparison Groups

This study investigated the multiple dimensions of self-perception in a sample of sexually abused and nonabused comparison girls (n = 140), with particular attention to self-perception in the scholastic, social, athletic, physical (appearance), and behavioral conduct domains. First, this study examined whether the five dimensions of self-perception were psychologically discrete. Second, the relationships between the self-perception factors and childhood sexual abuse were investigated using structural equation modeling. The results supported the multidimensionality of self-perception and suggested the presence of two distinct second-order self-perception factors: academic- and social-self. While the sexually abused girls indicated less positive perception for the academic-self than the comparison group, the two groups did not differ regarding the social-self. The findings highlight the importance of a multidimensional approach to self-perception in assessing and treating sexually abused children.
Thermophilic ostracod: aquatic metazoan with the highest known temperature tolerance.

The upper lethal temperature for an ostracod of the genus Potamocypris collected from a thermal stream ranged from 49°C for incubation of more than 5 hours to 55.75°C for 1-minute incubations. Field collections were held at 35°C for less than 24 hours before experimental incubations. Calculated temperatues for 50 percent mortality for 60, 40, 20, 10, 5, and 1 minute of exposure were 50.44°, 50.96°, 51.43°, 52.03°, 52.77°, and 55.12°C, respectively.