cssi/SciSciGPT-SciSciNet huggingface dataset:
Atrial electrophysiological effects of ibutilide infusion in humans.

Patients with persistent atrial fibrillation (AF) who respond to ibutilide infusion usually convert to sinus rhythm within 1 hour. However, little is known about the magnitude and time course of the drug's atrial electrophysiological effects. In the current study, the frequency content of the fibrillatory baseline on the ECG was used to quantify the effects of ibutilide infusion on AF. Nineteen patients (age 56 +/- 16 years) in persistent AF were studied. Nine of these were chronically treated with antiarrhythmic drugs. All subjects received ibutilide (1 mg i.v.) over 10 minutes and a second dose 10 minutes later as needed. An ECG was recorded and digitized throughout each of the 20 sessions (one patient had two separate cardioversions). A signal processing technique was then used to quantify the average rate of the fibrillatory baseline. After attenuating the QRS and T waves, the ECG was subjected to Fourier transformation. The average rate of fibrillatory activity was defined as the frequency corresponding to the peak power of this spectrum. The fibrillation rate declined by 20 +/- 12% during the initial dose of ibutilide. This effect was rapid with t1/2 = 4.2 minutes. Ibutilide induced slowing of AF was more intense and more rapid in patients who converted to sinus rhythm than in those who did not (25 +/- 5% vs 18 +/- 14% drop in rate, t1/2 3.4 minutes vs 6.3 minutes, P = 0.002). Ibutilide induced slowing of fibrillatory activity occurs rapidly and approaches steady state before the end of a 10-minute infusion. Although interaction with other antiarrhythmic drugs may have confounded the results, the speed and intensity of slowing correlated with conversion. These observations suggest that additional studies are warranted to determine if ibutilide dosing regiments can be optimized.
Informal reflection in pre‐service teacher education

Although numerous benefits to teaching and learning are associated with reflective practice, reflection is not a common professional behavior among practicing teachers, despite the flexibility of approach and application. Teacher educators continue to explore meaningful options when engaging pre‐service teachers in reflective thinking. The author, also a teacher educator, presents informal reflection as one such option. Informal reflection is grounded in the conceptualization of reflection articulated in the seminal works of Dewey and Schon and rests on the elements of practical theory, flexible structure, communal interaction and personal expression. Drawing from a 2004–2005 qualitative research study on weblogs in pre‐service teacher reflective practice, the author situates the elements of informal reflection in both theory and practice, presenting informal reflection as one approach to assist in the formation of reflective practitioners.
Mutagenicity of 22 N-nitrosamides and related compounds for Salmonella typhimurium TA1535.

Abstract Twenty-two N-nitrosamides and related compounds, including 14 nitrosoureas, 5 nitrosocarbamates, and one nitrosocyanamide, were tested at various concentrations for mutagenic activity towards Salmonella typhimurium TA1535 without the use of microsomes. The ether-water partition coefficient, solubility in water, and half-life in aqueous solution were also measured. Twenty compounds were mutagenic, with “standard mutagenic concentrations” (i.e. those producing 100 mutants/dish) of 0.0024–6500 μM. Standard mutagenic concentration was negatively correlated with the partition coefficient. Three compounds (ethyl 2-acetoxyethylnitrosocarbamate, nitrosocarbaryl, and methylnitrosobenzamide) were more active than the classic mutagen methylnitrosonitroguanidine. Nitrosocarbamates were at least 50 times more mutagenic than the corresponding nitrosoureas. Nitrosodihydrouracil and propylene-nitrosourea were more active than related compounds. Ethylnitrosocyanamide was 730 times more mutagenic than ethylnitrosourea. Fifteen of the test compounds (of which 14 were mutagenic) had previously been assayed in rats for carcinogenicity, all with positive results.
Sodium Ion Influences on Phosphorylations Associated with Oxidation of Succinate by Turnip Root Mitochondria

Sodium ions (10 -3 mole/liter) cause a marked increase in the ratio of phosphate esterified to oxygen utilized when turnip root mitochondria oxidize succinate. Separate study of the two phosphorylation sites associated with succinate oxidation indicates that the observed effect is a summation of differential responses of these sites to sodium ions. The activity of the first site, that associated with the reduction of cytochrome c, is stimulated about threefold by 10 -3 molar NaCl, whereas phosphorylation at the second site, coupled with the oxidation of ferrocytochrome c, is slightly inhibited by the same concentration of NaCl.
Precambrian apparent polar wandering: Evidence from North America

Abstract Over 95 paleomagnetic pole positions have been determined from North American Precambrian rocks, and they are listed in tabulations by Irving and McElhinny. Using rocks which are isotopically dated, five groups of pole positions can be defined, and these are consistent for rock units from widely separated areas of the North American continent. They are named for convenience (1) Keweenawan trend (age range 1000-1200 my) (2) Mackenzie trend (1200 my) (3) Elsonian trend (1300-1475 my) (4) Animikie-Sudbury trend (1600-2060 my) (5) Matachewan-Stillwater trend (2450-2485 my). An apparent polar wandering path can be constructed between the trends, and this will also incorporate data from rock units of uncertain age e.g. the Belt and Grand Canyon Series. Using an average rate of apparent polar wandering of 1°/5 my during the Phanerozoic for comparison, it suggests that the Precambrian was marked by long quasi static intervals in which the rate of polar shift was much less than 1°/5 my (2485-2140 my, 2060-1600 my, 1475-1200 my) separated by short periods of fairly rapid polar shift of much greater than 1°/5 my (2140-2060 my, 1600-1475 my, 1200-1000 my).
High-resolution electron microscopy of interlysosomal junctions

Five different malignant tumors and two nasal polyps were examined by electron microscopy for diagnosis purposes. In all cases occasional large cells containing lysosomes interconnected by characteristic junctions were observed. The interlysosomal junctions appeared organized in zig-zag and ladder like configurations. The ultrastructural and morphometric analyses of these junctions postulated that the two configurations represented the same structure viewed in two different sectioning planes. High-resolution electron microscopic evidence suggests that the interlysosomal junction is organized as a 35-40 A thick pleated ribbon extending between a 200-A wide interlysosomal space, in close contact with the adjoining lysosomal membranes, without apparent integration into the membrane.
An experimental investigation of nucleate boiling heat transfer from an enhanced cylindrical surface

Abstract In this study, nucleate boiling of the refrigerant R123 on the enhanced surface with 3-D micro-structures of a cylindrical tube is experimentally investigated. Water flows inside the tube and provides heat to the refrigerant outside the tube to boil. Experiments were performed at three pressures corresponding to the saturation temperatures of 4.4, 11.1, and 17.8 °C respectively to obtain the quantitative temperature effect on the boiling heat transfer coefficient. The results showed that boiling heat transfer on the enhanced surface can be divided into the low-heat-flux region (q″ 25 kW/m2). Within the low-heat-flux region, the boiling heat transfer coefficients increase linearly with increasing heat flux and the influence of the saturation temperature is insignificant. As the heat flux enters into the high-heat-flux region, the boiling heat transfer coefficients remain nearly flat as the heat flux increases within this region and the effect of saturation temperature is considerable. The boiling heat transfer coefficients at 11.1 and 17.8 °C are respectively 8.0–10.0% higher and 22.9–24.2% higher than the boiling heat transfer coefficients at 4.4 °C within the range of heat flux 25–62 kW/m2, which is equivalent to 1.2–1.8% increase in the boiling heat transfer coefficient per degree increase in the saturation temperature. In addition, for comparison with the enhanced tube, the experiments of boiling on the smooth surface of a plain tube were also performed for the saturation temperature of 4.4 °C. Results showed that the boiling heat transfer coefficients on the enhanced tube are 6–10 times those on the plain tube within the range of heat flux of 12–62 kW/m2.
Toll-Like Receptor-Independent Triggering of Dendritic Cell Maturation by Viruses

The ability of vaccination to empower natural immune defenses against viral infection is well illustrated by the worldwide eradication of smallpox and the partial elimination of polio after global vaccination efforts (74, 98). Unfortunately, these major successes have been infrequent, and diverse viruses continue to threaten our societies. The development of new vaccines, or the improvement of existing ones, is currently hindered by a limited knowledge of the intracellular mechanisms leading to the activation of antiviral adaptive immunity and of the viral elements responsible for its triggering upon infection. The use of the viral RNA analog poly(I:C), the discovery of the highly virus-responsive plasmacytoid dendritic cells (pDCs), and the identification of Toll-like receptors (TLRs) specific for viral elements have led to a greater understanding of the initiation of antiviral immunity. Nevertheless, there is little evidence to suggest that these elements are sufficient—or even necessary—for adaptive antiviral immune responses. A more comprehensive understanding of the mechanisms by which viruses trigger the development of adaptive immunity is therefore still needed. Recent work led to the identification of a novel pathway for the activation of conventional DCs (cDCs), the primary cells responsible for the generation of adaptive immunity. The triggering of this pathway leads to strong adaptive antiviral immunity in vivo even in the absence of TLR signaling. Here, we review the evidence for the identification and characterization of this pathway. Intracellular molecular candidates that may participate in this pathway are discussed, and a model for the triggering of DC maturation by viruses is presented.
Investigating noncovalent squarylium dye–protein interactions by capillary electrophoresis–frontal analysis

Noncovalent interactions between fluorescent probe molecules and protein analyte molecules, which typically occur with great speed and minimal sample handling, form the basis of many high sensitivity analytical techniques. Understanding the nature of these interactions and the composition of the resulting complexes represents an important area of study that can be facilitated by capillary electrophoresis (CE). Specifically, we will present how frontal analysis (FA) and Hummel-Dreyer (HD) methods can be implemented with CE to determine association constants and stoichiometries of noncovalent complexes of the red luminescent squarylium dye Red-1c with bovine serum albumin (BSA) and -lactoglobulin A. By adjusting solution conditions, such as pH or ionic strength, it is possible to selectively modify the binding process. As such, conditions for optimal selectivity for labeling reactions can be established by capillary electrophoresis–frontal analysis (CE–FA) investigations. © 2006 Elsevier B.V. All rights reserved.
Getting Smaller and Smaller

Robert F. Service's article on progress in developing miniature fuel cells for powering small electronic devices (“Shrinking fuel cells promise power in your pocket,” News Focus, 17 May, p. [1222][1]) is interesting and encouraging from the point of view of alternate energy strategies, but I wonder if the technology described is not already obsolete. Workable miniature fuel cells are coming on the market ([1][2]). The definition of a “fuel cell” should include not only cells using hydrogen and methanol, but also metal air cells. These are often called batteries, but they are not merely electricity-storing devices. Aluminum is especially interesting because the oxidation of aluminum produces enormous amounts of energy. To extract this energy in the usable form of electricity, aluminum is oxidized in an alkaline environment to aluminum hydroxide ([2][3]). Some of the more difficult problems of miniaturizing this technology have now been overcome ([3][4]). The Trimol Group is bringing out a unit 60 mm by 35 mm by 8 mm in size, which can power a wireless telephone for 25 hours of continuous talk ([1][2]). However depressing that prospect may be for the parents of teenagers, the problem of miniaturization of fuel cells has been solved. 1. [↵][5]See [www.trimolgroup.com/product_cellphone.htm][6]. 2. [↵][7]See [www.aluminum-power.com/technology.htm][8]. 3. [↵][9]See [fuelcell-magazine.com/articles/april101-2.htm][10]. [1]: /lookup/doi/10.1126/science.296.5571.1222 [2]: #ref-1 [3]: #ref-2 [4]: #ref-3 [5]: #xref-ref-1-1 "View reference 1 in text" [6]: http://www.trimolgroup.com/product_cellphone.htm [7]: #xref-ref-2-1 "View reference 2 in text" [8]: http://www.aluminum-power.com/technology.htm [9]: #xref-ref-3-1 "View reference 3 in text" [10]: http://fuelcell-magazine.com/articles/april01-2.htm
The Functional Role of the Domains of Troponin-C Investigated with Thrombin Fragments of Troponin-C Reconstituted into Skinned Muscle Fibers

Proteolysis of rabbit fast skeletal troponin-C (RSTnC) with thrombin produces four separate fragments containing the following Ca2+-binding site(s): TH1 (residues 1-120) sites I-III; TH2(121-159) site IV; TH3(1-100) sites I and II; and TH4(101-120) site III. We studied the ability of these fragments to restore the steady state isometric force in TnC-depleted skinned skeletal muscle fibers. Interestingly, we found that all investigated fragments of RSTnC possessed some of the properties of native RSTnC, but none of them could fully regulate contraction in the fibers like intact RSTnC. TH1 was the most effective in the force restoration (65%) whereas the smaller fragments developed about 50% (TH3 and TH4) or 20% (TH2) of the initial force of unextracted fibers. Additionally, much higher concentrations of TH2, TH3, and TH4 compared to RSTnC or TH1 were necessary for force development suggesting a decreased affinity of these fragments to their binding site(s) in the fibers. Like intact RSTnC, TH1 was able to interact with the fibers in a Ca2+-independent (Mg2+-dependent) manner, indicating that at a minimum, Ca2+-binding site III is required for this type of binding. The initial binding of the other fragments to the TnC-depleted fibers occurred only in the presence of Ca2+. TH2 and TH4 appeared to bind to two different binding sites in the fibers. The binding to one of the sites caused partial force restoration. This binding of TH2 and TH4 was abolished when Ca2+ was removed. TH2 and TH4 binding to the second site required Ca2+ initially but was maintained in the presence of Mg2+. This interaction of TH2 and TH4 partially blocked the rebinding of RSTnC to the fibers. The latter results suggest that site III or IV in these small fragments, when removed from the constraints of the parent protein, may assume conformations that allow them to function, to a certain extent, like both the regulatory sites (I and II) and the Ca2+-Mg2+ sites (III and IV) of TnC.
An evaluation of attention models for use in SLAM

In this paper we study the application of visual saliency models for the simultaneous localization and mapping (SLAM) problem. We consider visual SLAM, where the location of the camera and a map of the environment can be generated using images from a single moving camera. In visual SLAM, the interest point detector is of key importance. This detector must be invariant to certain image transformations so that features can be matched across di erent frames. Recent work has used a model of human visual attention to detect interest points, however it is unclear as to what is the best attention model for this purpose. To this aim, we compare the performance of interest points from four saliency models (Itti, GBVS, RARE, and AWS) with the performance of four traditional interest point detectors (Harris, Shi-Tomasi, SIFT, and FAST). We evaluate these detectors under several di erent types of image transformation and nd that the Itti saliency model, in general, achieves the best performance in terms of keypoint repeatability.
Spectral estimation for noise robust speech recognition

We present results on the recognition accuracy of a continuous speech, speaker independent HMM recognition system that incorporates a novel noise reduction algorithm. The algorithm is a minimum mean square error estimation tailored for a filter-bank front-end. It introduces a significant improvement over similar published algorithms by incorporating a better statistical model for the filter-bank log-energies, and by attempting to jointly estimate the log-energies vector rather than individual components. The algorithm was tested with SRI's recognizer trained on the official speaker-independent "Resource management task" clean speech database. When tested with additive white gaussian noise, the noise reduction achieved by the algorithm is equivalent to a 13 dB SNR improvement. When tested with desktop microphone recordings, the error rate at 13 dB SNR is only 40% higher than that with close-talking microphone at 31 dB SNR.
Mass spectrometers: instrumentation

Abstract Developments in mass spectrometry instrumentation over the past three years are reviewed. The subject is characterized by an enormous diversity of designs, a high degree of competition between different laboratories working with either different or similar techniques and by extremely rapid progress in improving analytical performance. Instruments can be grouped into genealogical charts based on their physical and conceptual interrelationships. This is illustrated using mass analyzers of different types. The time course of development of particular instrumental concepts is illustrated in terms of the s-curves typical of cell growth. Examples are given of instruments which are at the exponential, linear and mature growth stages. The prime examples used are respectively: (i) hybrid instruments designed to study reactive collisions of ions with surfaces: (ii) the Paul ion trap; and (iii) the triple quadrupole mass spectrometer. In the area of ion/surface collisions, reactive collisions such as hydrogen radical abstraction from the surface by the impinging ion are studied. They are shown to depend upon the chemical nature of the surface through the use of experiments which utilize self-assembled monolayers as surfaces. The internal energy deposited during surface-induced dissociation upon collision with different surfaces in a BEEQ instrument is also discussed. Attention is also given to a second area of emerging instrumentation, namely technology which allows mass spectrometers to be used for on-line monitoring of fluid streams. A summary of recent improvements in the performance of the rapidly developing quadrupole ion trap instrument illustrates this stage of instrument development. Improvements in resolution and mass range and their application to the characterization of biomolecules are described. The interaction of theory with experiment is illustrated through the role of simulations of ion motion in the ion trap. It is emphasized that mature instruments play a dominant role in most work using mass spectrometers. This is illustrated with recent results on the chemistry of C+.60 including the formation of covalent adducts with aromatic compounds. Quantitative analysis of methylated nucleosides and structural studies of the anti-cancer drug taxol are also discussed. A compendium of mass spectrometers constructed over the past three years is provided. This includes a variety of hybrid instruments, combinations of sector mass spectrometers with traps, instruments designed to study collision dynamics, and many more.
THE COMPACTION PROPERTIES of DEHYDRATED POTATO

The compaction behavior of two dehydrated potato granule materials has been studied in a cylindrical geometry. the effect of moisture content and the addition of dehydrated potato flake and potato starches has also been considered. the coefficient of friction and the stress anisotropy factor have been calculated from the pressure transmission measurements using a semi-particulate analysis previously used for polymer powders. the two granule types behaved more similarly under those conditions than their Brabender consistencies implied. the stress anisotropy factor tended to unity with increasing moisture content. the presence of other potato materials had a considerable effect on the compaction of the granules. These results indicate that the performance of processes that involve compaction of these materials, such as extrusion, will vary considerably with composition and moisture content.
Transcriptional regulation of gene expression: Mechanisms and pathophysiology

Transcription factors are key mediators of the genetic programs that underlie human development and physiology. Mutations in genes that encode transcription factors or in DNA sequences to which these factors bind may adversely affect gene expression and result in disease. Mutations in genes encoding transcription factors often have pleiotropic effects because each transcription factor is involved in the regulation of multiple genes. For several transcription factors, germline mutations have been shown to result in malformation syndromes whereas somatic mutations in the same genes contribute to the multistep process of tumorigenesis. The study of transcription factors and their involvement in human disease thus provides insight into the molecular mechanisms underlying human development, physiology, dysmorphology, and oncology.
Higher Prevalence of Smoking in Patients Diagnosed as Having Obstructive Sleep Apnea

Nightly nicotine withdrawal as well as other respiratory and pulmonary effects of smoking may result in sleep-disordered breathing, especially obstructive sleep apnea (OSA). We hypothesize that there is higher prevalence of smoking in patients with OSA. We also hypothesize that smoking is an independent risk factor for OSA. The aim of this study is to determine whether there is a higher prevalence of smoking in patients with OSA compared with patients who do not have OSA. To investigate this, we randomly selected a group of 108 patients who were diagnosed as having OSA, defined by an apnea-hypopnea index (AHI) of greater than 10 events per hour. We compared their smoking history with another randomly selected group of 106 patients without OSA, defined by an AHI of less than five events per hour. The prevalence of smoking in patients with OSA was found to be 35%, whereas it was only 18% in patients without OSA. Logistic regression analyses were performed to investigate the effects of smoking while adjusting for age, gender, body mass index (BMI), and number of alcoholic drinks per week. While holding fixed the BMI, gender, age, and number of alcoholic drinks per week, current smokers were found to be 2.5 times more likely to have OSA than former smokers and nonsmokers combined (odds ratio = 2.5, CI 1.3-4.7, p = 0.0049), and 2.8 times more likely to have OSA than former smokers alone (odds ratio = 2.8, CI = 1.4-5.4, p = 0.0028). Adjusted for BMI, gender, age, and number of alcoholic drinks per week, former smokers were not more likely than never smokers to have OSA (odds ratio = 1.2, CI = 0.55-2.7, p = 0.64). We conclude that cigarette smoke may be an independent risk factor for OSA in this referral population.
Thoracoscopic vertebral body replacement with an expandable cage after ventral spinal canal decompression.

OBJECTIVE: Minimally invasive thoracic anterior surgery using a thoracoscopic approach has evolved to include spinal biopsy, debridement, discectomy, decompressive corpectomy, interbody fusions, and internal fixations. Minimal access techniques can potentially decrease surgical access morbidity and also reduce the time required for recovery and healing. The thoracoscopic approach for decompression, stabilization, and anterior vertebral reconstruction of thoracolumbar fractures is described. METHODS: In this article and video, we discuss patient selection, surgical positioning, port placement, thoracic level localization, exposure and removal of fractured vertebral bodies, anterior vertebral column reconstruction using an expandable cage, instrumentation, and postoperative management. RESULTS: The potential advantages of using a minimally invasive thoracoscopic approach include direct trajectory to anterior spine pathology, minimal tissue and rib retraction, and decreased postoperative pain and length of hospital stay. The associated disadvantages include the steep learning curve for the surgeon, the need to operate with two-dimensional visual information and long instruments, and the requirement that one have an experienced surgical assistant. CONCLUSION: Minimally invasive surgery using a thoracoscopic approach for vertebral body replacement with an expandable cage can be performed safely. Expandable cages facilitate the vertebral body reconstruction via minimal access surgery.
Chemical and Physical Characteristics of Beef Chuck Muscles: Effect of Electrical Stimulation, Hot Boning and High Temperature Conditioning

Chucks from 12 electrically stimulated steer carcasses were randomly assigned to one of 3 treatments: (1) cold boned [CB], (control), (2) hot boned [HB], and (3) hot boned/time conditioned [HB/TC], (5 hr at 18°C). Infraspinatus, Serratus ventralis, Subscapularis, Supraspi-natus, Teres major, and Triceps brachii were excised from each chuck according to treatment conditions. No differences (P > 0.05) were noted among treatments for muscle yields, cooking loss, proximate composition, or collagen content; however, differences (P<0.05) were found among muscles. Differences (P < 0.05) were found among treatments and muscles for ultimate pH, sarcomere length, Warner Bratzler shear values, and Hunter color ‘a’ values. Sarcomere length of muscles assigned to CB treatment were longer (P < 0.05) than HB and HB/ TC treatments.
THE CHARITY OF THE UNCHARITABLE

If I understand the common view among modern intellectuals, income redistribution is considered to be a rather simple and almost entirely ethical matter. There are, basically, two theories. The first is that those of us who are well-off use the state as a mechanism for making gifts to the poor. This is well represented by James Rodgers and Harold Hochman in their article, ‘Pareto Optimal Redistribution’.1 The second view, which I shall call the ‘Downsian’, is that in a democracy the poor are able to use their votes to obtain transfers from the rest of society (Anthony Downs [2, esp. pp. 198–201]). These two views are sometimes combined into the view that the bulk of the population takes money from the rich and gives it to the poor by use of the democratic process.
Fetal blood sampling and fetal thrombocytopenia.

The purpose of this investigation is to determine whether fetal thrombocytopenia is a risk factor for puncture site bleeding. Three groups of fetuses either with or at known risk for thrombocytopenia
Broken Clubs and Expletives: The Sources of Stress and Coping Responses of Skilled and Moderately Skilled Golfers

There has been a large growth of sport psychology stress/coping research in the last decade. However, skilled and moderately skilled golfers have not received much research attention. Therefore, the purposes of this qualitative, descriptive study were to assess the sources of stress and coping responses of skilled and moderately skilled golfers with regard to performance related stress. Semi-structured interviews were conducted with 11 golfers who played a minimum of 10 rounds of golf during the current golf season. Using the analytic strategies described by Cote, Salmela, Baria, and Russell (1993) and Lincoln and Guba (1985), a research team performed an inductive analysis that resulted in the emergence of the following coping strategies: cognitive strategies, relaxation techniques, off course efforts, golf course strategies, avoidance coping, and emotion-focused coping. The results are discussed in terms of current coping research in sport and applied implications are offered.
Theoretical analysis of the MCD spectra of some singlet-triplet transitions in formaldehyde

Abstract A recently developed theoretical treatment of the magneto-optical activity of singlet-triplet transitions in molecules which are near-symmetric rotors is employed in simulation of the MCD spectra associated with some singlet-triplet transitions in formaldehyde. The theoretical results are compared with the relevant experimental data, and the agreement between theory and experiment is found to be satisfactory.
Effect of Cortical Bone Thickness on the Magnitude and Classification of Hill Sachs Lesions Verses Glenoid Lesions

The shoulder is the most dislocated major joint in the body; approximately 2% of the population will dislocate their glenohumeral joint between the ages of 18 and 70 [1]. Hill-Sachs lesions, compression fractures resulting from the impaction of the posteroloateral humeral head against the solid anterior rim of the glenoid, occur in roughly 30–40% of all anterior dislocations. Humeral head defects have been linked to postoperative recurrent dislocations and overall instability of the shoulder following stabilization procedures for the capsule [2]. However, the forces and deformations required to create these lesions during shoulder dislocation should be identified to properly develop injury models and new repair techniques. Therefore, the objective of this study was to determine the forces required to create bony lesions on the humeral head and quantify the size of the resulting lesions. In order to achieve this objective, a repeatable testing protocol was developed to consistently produce Hill Sachs lesions.Copyright © 2010 by ASME
Resonance Raman Spectroscopic Evidence for an Anionic Flavin Semiquinone in Bovine Liver Monoamine Oxidase

The flavoprotein monoamine oxidase B (MAO B) from bovine liver, as isolated, has an unusual additional absorption band at 412 nm, which is similar to the absorption of its anionic flavin semiquinone form, (Fl∸), and other typical (Fl∸) flavoproteins. Denatu ration of the enzyme results in the elimination of this anomalous absorption. The resonance Raman (RR) spectrum of MAO B as isolated is virtually identical to that of its dithionitereduced (Fl∸) form. Both spectra show features similar to those of the RR spectrum of the (Fl∸) form of Aspergillus niger glucose oxidase (GO) in the region between 300 and 1700 cm−1 with 406.7 nm excitation. These features are readily distinguishable from those of oxidized flavin, neutral fiavin semiquinone, and hemoprotein, strongly suggesting the presence of an (Fl∸) form in MAO B as isolated, even with preparations isolated in the absence of light. There are significant differences between the RR spectra of the (Fl∸) form of MAO B and those of GO or the published RR spectra of the (Fl∸) form of Damino acid oxidase with excess substrate analog. At least some of these differences can be attributed to the different binding of flavin in the three enzymes. No EPR signals due to (Fl∸) are observed in MAO B as isolated. The dithionite-reduced (Fl∸) form exhibits 50% less EPR signal than that expected from the absorption spectrum, which suggests a possible coupling of the (Fl∸) fiavin with a paramagnetic center of unknown identity in the protein. The implications of these observations on MAO B with the current view of its catalytic mechanism are discussed.
A simple conduction model for skin burns resulting from exposure to chemical fireballs

A simple conduction model is developed for skin burns resulting from a short-duration heat pulse of the type that commonly occurs with typical chemical fireballs. This model predicts the absorbed heat values necessary to produce second and third degree burns for constant heat pulses of 1 to 36 s duration. The results of the model are shown to correlate well with test data for swine and human skin.
Genetic regulation of endothelin-1 in vascular endothelial cells.

Endothelin-1 (ET-1) is a potent vasoconstrictor and smooth muscle cell mitogen synthesized and secreted by endothelial cells. This vasoactive peptide is genetically regulated by many of the cytokines, hormones, and physical forces that are involved in vascular disease processes. Transcriptional regulation of the ET-1 gene depends upon the cis-acting elements of the ET-1 promoter and their interaction with the protooncogene products Fos and Jun as well as other DNA-binding proteins.
Optimization of the separation and detection of the enantiomers of isoproterenol in microdialysis samples by cyclodextrin-modified capillary electrophoresis using electrochemical detection.

Isoproterenol is a chiral catecholamine with a half-life of elimination of less than 10 min. In order to study the pharmacokinetics of this compound using microdialysis sampling, an analytical method was needed which could resolve the individual enantiomers of isoproterenol and required less than 1 μl of sample. A capillary electrophoretic method using a run buffer containing methyl-O-β-cyclodextrin as a chiral recognition agent was developed which could resolve the enantiomers of isoproterenol. The detection limits using UV absorbance detection were found to be too high to determine the concentration of isoproterenol in plasma for a sufficient time following administration to establish the pharmacokinetics. The detection limits were decreased three orders of magnitude to 3 ng/ml by using an amperometric detector. The detection limits were decreased to 0.6 ng/ml using an on-column concentration technique in which peak stacking was accomplished by following the sample injection with a plug of acid.
A numerical study on TGFs and relativistic feedback discharges

Terrestrial gamma-ray flashes are sub-millisecond bursts of >1 MeV photons originating from thunderclouds in the earth's atmosphere [e.g., Fishman et al., Science, 264, 1313, 1994]. They are normally produced in the initial stage of positive intra-cloud lightning discharges [e.g., Shao et al., JGR, 115, A00E30, 2010; Lu et al., GRL, 37, L11806, 2010; Cummer et al., GRL, 38, L14810, 2011]. In addition to the relatively short TGFs, thunderclouds and lightning can also make minute long gamma-ray glows according to ground-based [e.g., Chilingarian et al., PRD, 82, 043009, 2010] and airborne measurements [e.g., Smith et al., JGR, 116, D20124, 2011].
Changes in the Extracellular Matrix of the Human Optic Nerve Head in Primary Open-Angle Glaucoma

Using immunofluorescent staining, we were able to characterize the changes in composition and distribution of the macromolecules making up the extracellular matrix of the lamina cribrosa of the glaucomatous human optic nerve head. In tissue adjacent to the glaucomatous cups, there was marked disorganization and loss of fibers of elastin within the cores of the cribriform plates. Collagen type VI, normally sparse, increased in quantity considerably throughout the lamina cribrosa in glaucomatous eyes with all degrees of damage. Collagen type IV and other basement membrane macromolecules appeared to extend into nerve bundles, presumably filling in spaces previously occupied by nerves. There was no appreciable change in the postlaminar region, which indicates the specificity of the extracellular matrix changes in the lamina cribrosa. Our results indicate that changes in the extracellular matrix play an important role in the progression of the glaucomatous process and may be a causative agent of the disease.
Luminescence studies of cerium(III) incorporated in silica gels prepared using sol-gel methods

Abstract Sol-gel methods have been adapted for the incorporation of cerium(III) into a silica gel network, and the resulting gels have been prepared either with or without the use of formamide as a drying control chemical additive (DCCA). The use of formamide and Ce(III) has been found to result in lanthanide-assisted hydrolysis of the amide, leading to crystallization phenomena during gelation. We describe strategies to avoid this, as well as the results of luminescence studies on the Ce/ silica gels. The latter have been used to observe the characteristics luminescence of gel-supported cerium, and have also been employed as a probe of the gelation process. This has been found to lead to increasing luminescence intensity, with the most significant increases occurring after gelation and during the drying stage.
Topology of Spade Drills for Wood Drilling Operations Part 2: Spade Drill Point Cutting Geometry Analysis

Based on the spade drill point's mathematical models established in Part 1 of this paper, a detailed methodology for the analysis of the cutting edges and angle distributions along these edges is given. The analysis addresses the most important geometric elements of the bit including the tip, major cutting edge, and the chisel edge profiles, as well as the rake and clearance angle distribution along these cutting edges. In unison, the geometric model of the spade bit and the analysis procedure described in this part of the paper have laid the foundation for a methodology and a software package for a detailed geometric analysis of all relevant cutting mechanics related geometric entities of the drill. This, in turn, constitutes the first prerequisite for assessing the cutting performance of these tools.
A decomposition approach for solving a broadcast domination network design problem

We consider an optimization problem that integrates network design and broadcast domination decisions. Given an undirected graph, a feasible broadcast domination is a set of nonnegative integer powers fi assigned to each node i, such that for any node j in the graph, there exists some node k having a positive fk-value whose shortest distance to node j is no more than fk. The cost of a broadcast domination solution is the sum of all node power values. The network design problem constructs edges that decrease the minimum broadcast domination cost on the graph. The overall problem we consider minimizes the sum of edge construction costs and broadcast domination costs. We show that this problem is NP-hard in the strong sense, even on unweighted graphs. We then propose a decomposition strategy, which iteratively adds valid inequalities based on optimal broadcast domination solutions corresponding to the first-stage network design solutions. We demonstrate that our decomposition approach is computationally far superior to the solution of a single large-scale mixed-integer programming formulation.
Cerenkov emission induced by external beam radiation stimulates molecular fluorescence

Purpose: Cerenkov emission is induced when a charged particle moves faster than the speed of light in a given medium. Both x-ray photons and electrons produce optical Cerenkov photons in everyday radiation therapy of tissue; yet, this phenomenon has never been fully documented. This study quantifies the emissions and also demonstrates that the Cerenkov emission can excite a fluorophore, protoporphyrin IX (PpIX), embedded in biological phantoms. Methods: In this study, Cerenkov emission induced by radiation from a clinical linear accelerator is investigated. Biological mimicking phantoms were irradiated with x-ray photons, with energies of 6 or 18 MV, or electrons at energies 6, 9, 12, 15, or 18 MeV. The Cerenkov emission and the induced molecular fluorescence were detected by a camera or a spectrometer equipped with a fiber optic cable. Results: It is shown that both x-ray photons and electrons, at MeV energies, produce optical Cerenkov photons in tissue mimicking media. Furthermore, we demonstrate that the Cerenkov emission can excite a fluorophore, protoporphyrin IX (PpIX), embedded in biological phantoms. Conclusions: The results here indicate that molecular fluorescence monitoring during external beam radiotherapy is possible.
Mitochondrial dysfunction in mouse trisomy 16 brain.

Abstract Mitochondrial function in the brain of mouse trisomy 16, an animal model of Down syndrome with accelerated neuron death, was studied in isolated cortex mitochondria. Using an oxygen-sensitive Clarke electrode, a selective 16% decrease in respiration was detected with the Complex I substrates malate and glutamate but not with the Complex II substrate succinate. Western blotting revealed a 20% decrease in the 20 kDa subunit of Complex I in Ts16 brain cortex homogenates with no significant decrease in marker proteins for the other complexes of the electron transport chain. Although no differences in H2O2 production or maximal calcium uptake were detected in the Ts16 mitochondria, there was an 18% decrease in pyruvate dehydrogenase levels, a change associated with oxidative stress in ischemia. These results are similar to those found in Parkinson's disease suggesting some neurodegenerative diseases may have mitochondrial pathology as a common step.
Analysis Of Medicare Advantage HMOs Compared With Traditional Medicare Shows Lower Use Of Many Services During 2003–09

Enrollment in Medicare Advantage, the managed care program for Medicare beneficiaries, has grown rapidly, from 4.6 million enrollees in 2003 to 12.8 million by 2012, or 27 percent of all current Medicare beneficiaries. We analyzed utilization patterns of enrollees in Medicare Advantage health maintenance organization (HMO) plans compared to matched samples of people in traditional Medicare during 2003–09, to ascertain whether the HMO enrollees demonstrated different levels of use of services, which can be a hallmark of more integrated care. We found that utilization rates in some major categories, including emergency departments and ambulatory surgery or procedures, generally were 20–30 percent lower in Medicare Advantage HMOs in all years. Medicare Advantage HMO enrollees initially had lower rates of ambulatory visits and hospitalizations, although these rates converged by 2008; they also received about 10 percent fewer hip or knee replacements. In contrast, HMO enrollees underwent more coronary bypass s...
Immunopathogenic Interaction of Environmental Triggers and Genetic Susceptibility in Diabetes: Is Epigenetics the Missing Link?

Autoimmune type 1 diabetes is caused by an interactive combination of genetic and environmental factors, most of which remain unknown. Each individual appears to have a unique combination of these factors that allow for their susceptibility to disease. Investigators have long searched for physiological mechanisms that could link diverse environmental events to inheritable genetic traits and the aberrant gene expression in immune cells. Much of this search has focused on either uncovering elusive gene polymorphisms found in at-risk populations or on finding common elements in the lives of susceptible individuals that “trigger” their immune system toward a self-destructive path (1,2). To date, only a few gene polymorphisms have linked to susceptibility, with none so far proven both essential and sufficient to promote disease (1). The search for environmental etiological agents in this multifactorial disease has been no less difficult, since each individual afflicted appears to have a unique set of factors promoting autoimmunity rather than a single or few common triggers (2). So how can such a diverse set of environmental stimulators rapidly and reversibly trigger a variety of undefined genetic regions to promote the loss of something as basic to normal physiology as tolerance of self? Is there a common mechanism even when the end targets are elusive and environmental slings and arrows are so diverse? Enter epigenetic gene regulation into the tableau, adding a …
THE PACIFIC SALMON WARS: What Science Brings to the Challenge of Recovering Species

▪ Abstract Politicians, scientists, government agencies, and the public are all engaged in recovery planning for Pacific salmon. In order for science to fulfill its potential in the arena of salmon recovery planning, several shortcomings of the science and its application to decision-making must be rectified. The definition of conservation units using genetic and phylogenetic inference needs to be sharpened. Ecological analyses must get beyond casting blame for past declines in salmon numbers and examine mixed strategies of management that consider interactions between hatcheries, harvest, hydropower, and habitat factors as well as background natural stresses and invasive species. Glib acceptance of expert opinion and extrapolated or inferred data should be tempered. To deal with uncertainty, recovery teams should engage in scenario analyses in which a wide variety of assumptions are played out. Finally, there is a pressing need for analyses aimed at determining what circumstances and communication strate...
Experience-based consulting: The value proposition

Consulting is a profession universally accepted and well entrenched throughout the business world. Whether it is providing objective analysis, supplying a specific expertise, managing a project, or simply adding extra manpower, consultants can add value. However, what are the attributes of a good consultant? In health care, with the rapid pace of emerging technologies, economic intricacies, and the complexities of clinical care, hands-on experience is the key. Recognizing the power of consultants with hands-on experience, the Department of Radiology at Massachusetts General Hospital launched the Radiology Consulting Group, an "experience-based" model for consulting that may potentially shift the profession's paradigm.
Nanoscale Heating of the Near Field Transducer in Heat Assisted Magnetic Recording

Current heat assistance magnetic recording hard disk drive systems are designed to heat a 20 nm writing spot on the disk to more than 400 °C by a near field transducer (NFT) located within the slider and spaced a few nanometers from the disk. It is important for the NFT to remain relatively cool to insure that it will not fail during the required lifetime of the drive. Due to the nanometer scale separation between the heated spot and the NFT, the heat exchange between them cannot be accurately calculated by conventional methods. This paper first explains why the conventional models of heat transfer fail at the nanoscale. Then, we estimate the heat radiation and heat conduction due to phonon tunneling using an extension of Planck’s law from equilibrium systems to systems with a non-vanishing heat flux. It is shown that the heat transport across a few nanometers wide gap is expected to be high enough to provide significant back-heating of the NFT from the heated spot on the disk.