cssi/SciSciGPT-SciSciNet huggingface dataset:
Dependence of equatorial bubbles and bottomside spread F on season, magnetic activity, and E × B drift velocity during solar maximum

[1] Equatorial bubbles occur sporadically, so that the resulting scintillation that disrupts transionospheric RF propagation is unpredictable. Furthermore, this randomness prevents the systematic observation of the formation of bubbles necessary for making progress in their prediction. However, recent results indicate that a necessary condition for bubble formation is bottomside spread F (BSSF); that BSSF is a function of the F region dynamo electric field; and that this field is dependent on magnetic activity and on season. This work measures these conditions using an array of ionospheric sounders in conjunction with other spread F observations, all of which are ground-based, in the western American sector, during solar maximum. Three spread F levels are observed: total BSSF and strong BSSF, both measured near the dip equator, and macroscopic bubbles measured at the equatorial anomaly. The three independently measured thresholds form a hierarchy in which macroscopic bubbles are a subset of strong BSSF, which is a subset of total BSSF. Each level decreases as a linear function of Kp averaged in the 6 hours preceding observation during March, April, September, and October, and during November–February; however, during May–August the levels are small and are independent of Kp. As a result, the probability of occurrence of each level, most importantly of macroscopic bubbles, is a quantitative function of Kp and season. The seasonal variation of Kp dependence indicates that the suppression of irregularities results from the decrease in the maximum prereversal vertical drift velocity of the equatorial F layer and therefore from the decrease in the eastward electric field.
Time-Perspective and Feeling-Tone: A Study in the Perception of the Days

(1953). Time-Perspective and Feeling-Tone: A Study in the Perception of the Days. The Journal of Psychology: Vol. 35, No. 2, pp. 253-257.
Outcomes measurement in voice disorders: application of an acoustic index of dysphonia severity.

Purpose The purpose of this experiment was to assess the ability of an acoustic model composed of both time-based and spectral-based measures to track change following voice disorder treatment and ...
Highly hydrated poly(allylamine)/silica magnetic resin

The creation of multifunctional nanoma- terials by combining organic and inorganic compo- nents is a growing trend in nanoscience. The unique size-dependent properties of magnetic nanoparticles (MNPs) make them amenable to numerous applica- tions such as carriers of expensive biological catalysts, in magnetically assisted chemical separation of heavy metals and radionuclides from contaminated water sources. The separation of minor actinides from high- level radionuclide waste requires a sorbent stable in acidic pH, with ease of surface functionalization, and a high capacity for binding the molecules of interest. For the described experiments, the MNPs with 50 nm average size were used (size distribution from 20 to 100 nm and an iron content of 80-90 w/w%). The MNPs that have been double coated with an initial silica coating for protection against iron solubilization and oxidation in nitric acid solution (pH 1) and a second silica/polymer composite coating incorporat- ing partially imbedded poly(allylamine) (PA). The final product is magnetic, highly swelling, containing (95% water, with (0.5 mmol amines g -1 available for functionalization. The amine groups of the mag- netic resin were functionalized with the chelating molecules diethylenetriaminepentaacetic acid (DTPA) and N,N-dimethyl-3-oxa-glutaramic acid (DMOGA) for separation of minor actinides from used nuclear fuel.
Subcellular localization of proteins encoded by oncogenes of avian myeloblastosis virus and avian leukemia virus E26 and by the chicken c-myb gene

Abstract Analysis of the subcellular location of the proteins encoded by the oncogenes of avian myeloblastosis virus and avian leukemia virus E26 (p45 v-myb and p135 gag-myb-ets , respectively) and by the chicken c-myb gene (p75 c-myb ) shows that all three proteins are located in the nucleus. In AMV-infected (but not transformed) chicken fibroblasts p45 v-myb also resides in the nucleus, indicating that a nuclear location of p45 v-myb in these cells is not sufficient to achieve transformation. In AMV-transformed mye-loblasts a small fraction of p45 v-myb occupies an additional site in the perinuclear region of the cytoplasm. If the myeloblasts are caused to differentiate to macrophages, most of p45 v-myb is found in the cytoplasm. This redistribution of p45 v-myb within the cell may be responsible for reversion of the transformed phenotype.
Effects of butylated hydroxyanisole on the aryl hydrocarbon hydroxylase of rats and mice.

Abstract The effects of butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) on the aryl hydrocarbon hydroxylase (AHH) activities in the liver, lung and skin of rats and mice have been studied to examine the possible mechanisms of the anticarcinogenic actions of these compounds. Both compounds inhibit the hydroxylase activities of hepatic microsomes and nuclei, with BHA a more potent inhibitor than BHT. The AHH of lung microsomes is inhibited to a lesser extent by BHA and BHT than that of the liver. The AHH activities of both liver and lung microsomes become less susceptible to the inhibition after pretreatment of the animals with 3-methylcholanthrene (MC) or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) but phenobarbital (PB) pretreatment does not produce such an effect. In skin homogenates, however, the AHH activities of control rats and mice are not inhibited by BHA and BHT. The only skin sample which is inhibited by BHA and BHT is that from TCDD-pretreated mice. It has been established that the extent of inhibition with different samples is related to the concentration of BHA in the incubation but not to the amounts or specific activities of microsomes used. Double reciprocal plots suggest that BHA exerts a mixed inhibition on the hydroxylase of liver microsomes with a Ki of 7.7 μM. Analysis of the metabolites of benzo[a]pyrene (BP) shows that BHA inhibits the formation of various metabolites uniformly without changing the regio-selectivity of the enzyme system. The mechanism of inhibition has also been studied with a reconstituted AHH system consisting of cytochrome P-450 (P-450), reductase and phospholipid. The system with P-450 isolated from PB-induced microsomes is inhibited to a much greater extent than that with MC-induced P-450. The results indicate that the inhibitory action of BHA is dependent on the species of the animal, tissue types and treatment with inducers.
Simazine: Degradation by Soil Microorganisms

A soil fungus, Aspergillus fumigatus Fres., is effective in the degradation of the herbicide 2-chloro-4,6-bis(ethylamino)-s-triazine (simazine). The degradation of both ring-and chain-labeled (C14) simazine was observed in an unamended and an amended (sucrose) basal medium. A loss of C14 occurred in all culture solutions containing either ring-or chain-labeled simazine, but the decrease in activity observed was greater with chain-labeled than with ring-labeled simazine. Chromatographic evidence indicates that A. fumigatus may possess a degradation mechanism unlike that which occurs in corn plants.
Superoxide Scavengers Do Not Prevent Ischemia-Induced Alteration of Cerebral Vasodilation in Piglets

ABSTRACT: Piglet brains generate superoxide during postischemic reperfusion, and topical application of activated oxygen species alters pial arteriolar responses. We investigated effects of pretreatment with scavengers of superoxide and H2O2 on ischemia-induced alterations of pial arteriolar responses in anesthetized newborn pigs. Four groups were studied: 1) time control, 2) untreated ischemia, 3) ischemia pretreated topically and systemically (conjugated to polyethylene glycol) with superoxide dismutase (SOD) and catalase, and 4) ischemia pretreated with Tiron. Pretreatment with SOD conjugated to polyethylene glycol alone during postischemic reperfusion effectively removed superoxide from its site of generation during postischemic reperfusion, but topical SOD was used also as insurance. Piglets were studied before and after 20 min of total cerebral ischemia caused by maintaining intracranial pressure above mean arterial pressure. As reported previously, before ischemia, hypercapnia and isoproterenol dilated pial arteries and arterioles and hypercapnia but not isoproterenol increased cortical periarachnoid cerebrospinal fluid 6-keto-prostaglandin F1α, measured as an index of cerebral cortical prostacyclin synthesis. After cerebral ischemia, pial arterioles did not dilate in response to hypercapnia and 6-keto-prostaglandin F1α did not increase, but dilation to isoproterenol was unchanged. The present study found that treatment with SOD/catalase or Tiron did not prevent loss of vasodilation to hypercapnia or the loss of hypercapnia-induced cerebral 6-keto-prostaglandin F1α synthesis after cerebral ischemia. The postischemic loss of cerebral vasodilation to hypercapnia does not appear to involve superoxide or a subsequent reduced form of oxygen.
Ecological genetics: introductory note

– The eight papers resulting from the Ecological Genetics session of the symposium Ecology of Stream Fish: State of the Art and Future Prospects (Luarca, Spain, April 1998) describe the use of molecular genetic markers to investigate questions of population distinctness, interbreeding, and adaptation in five salmonid species. Widely contrasting ecological distinctions described in four species indigenous to western North America [steelhead (rainbow) trout, sockeye salmon, pink salmon and bull trout] reflect past natural and human-induced activities, serving to guide future management and conservation actions through optimizing adaptive opportunities, and preventing genetic losses through localized extinctions. Studies of brown trout contrast widespread introgressions from exogenous hatchery introductions that threaten the integrity of native Spanish populations with a reduced threat based on use of indigenous fish in Portuguese hatcheries. A 9-year study of natural progeny of two genetically distinct Swedish brown trout populations introduced to a previously trout-free area identifies apparent local adaptations as a model to guide other translocations.
Mathematical modeling of alternative pad designs in flip-chip soldering processes

The purpose of this paper is to present a mathematical representation of the forces that govern the final positioning of Si chips in flip-chip technology. These forces arise from the tendency of the system to minimize its free energy; and in the paper, we are presenting a mathematical technique, based on the public domain Surface Evolver computational package. By explicitly calculating the restoring forces, we could examine the effect of system geometry and specifically examine the role played by the pad shape in affecting these phenomena. This computational technique is thought to have a considerable potential for addressing a broad range of related problems in flip chip technology.
Quantum-mechanical carrier of the imprints of gravitation

We exhibit a purely quantum-mechanical carrier of the imprints of gravitation by identifying for a relativistic system a property which (i) is independent of its mass and (ii) expresses the Poincar\'e invariance of spacetime in the absence of gravitation. This carrier consists of the phase and amplitude correlations of waves in oppositely accelerating frames. These correlations are expressed as a Klein-Gordon-equation-determined vector field whose components are the ``Planckian power'' and the ``rms thermal fluctuation'' spectra. The imprints themselves are deviations away from this vector field.
The role of high‐dose chemotherapy and stem cell rescue in the treatment of malignant brain tumors: A reappraisal

The outcome for children with malignant brain tumors has improved modestly in recent years. Notable is the improved 5-yr disease-free survival for those children with 'standard-risk' medulloblastoma and other primitive neuro-ectodermal tumors (PNET) (i.e. tumors without neuraxis dissemination at presentation). For other children with newly diagnosed malignant brain tumors, especially in the absence of radical surgical resection, the outcome remains poor despite surgery, irradiation and conventional chemotherapy. Patients whose tumors recur despite initial therapy continue to experience a dismal outlook with these conventional strategies of treatment. In an attempt to improve the outlook for such brain tumor patients with poor prognoses, strategies utilizing high-dose (potentially myeloablative) chemotherapy with autologous stem cell rescue have been developed. These studies, conducted initially in patients with recurrent tumors, were then extended to patients with newly diagnosed malignant gliomas and brain-stem tumors, as well as to young children with various malignant brain tumors at diagnosis in an attempt to avoid irradiation to the brain. The results of several of these studies are summarized, updating information reviewed in an earlier summary in 1996, demonstrating durable disease-free survival for a proportion of patients with recurrent malignant gliomas and medulloblastomas/PNET, as well as encouraging data in some of those patients with newly diagnosed brain tumors.
Detector efficiency and signature efficiency in the study of exotic nuclei

Abstract The role of highly efficient detector systems and highly efficient signatures of structure in the study of exotic nuclei is discussed. The discovery of “critical point symmetries” in the study of phase transitional behavior in nuclei, with applications to unknown regions, is also discussed.
THE FATE OF INDEPENDENT THOUGHT IN TRADITIONAL CHINA

China, like a huge dragon, gobbles all in its path. Like a huge vat, dyes all the same color. Sun Jingxuan, A Spector Prowls Our Land (1980)
Virtual teams: team control structure, work processes, and team effectiveness

Seeks to determine the impact managerial controls have on the effectiveness of virtual teams. Using an experimental design compares self‐directed virtual teams to counterparts where behavior controls are used as a method of managerial control. The data were collected using 51 student teams of three or four members each from three different countries. The results indicate that the most satisfied team members were in virtual teams with effective coordination and communication. Members of self‐directed virtual teams report higher individual satisfaction with the team and project, while different control structures had no significant impact on virtual team performance. Future research should investigate how these findings generalize to organizational workers, rather than just looking at students. This paper is just a first step investigating one type of managerial control: behavior controls. The small amount of research that has been published on virtual teams has primarily concentrated on self‐directed teams...
The calculation of STM images, STS spectra, and XPS peak shifts for galena: New tools for understanding mineral surface chemistry

Abstract Scanning tunneling microscope (STM) images and spectra of galena (PbS) surfaces were calculated using ab-initio methods, not only to interpret experimentally collected STM data, but also to gain insight into changes of the electronic structure at an atomic level that are associated with surface reactions such as heterogeneous oxidation. STM images of the upper valence band of galena show a periodic array of spots which could be matched to either Pb or S. Our calculations show that these spots mainly stem from electronic states with sulfur 3p character near the Fermi level. In addition, images of the mid-band gap and lower conduction band also show states that we calculate as being due to orbitals with lead 6p character. If the galena surface is exposed to air, more and more of the formerly bright sulfur spots appear as dark spots. This agrees with the calculated depletion of the upper valence band electronic density near sulfur sites after adsorbing oxygen atoms to them. Therefore, tunneling microscopy on semiconducting sulfides can not only be understood as a tool of visualizing single atoms, but also a probe for surface sites at an atomic level that can be most easily oxidized. Modeling galena with infinitely wide slabs as opposed to clusters shows significant differences in the oxidation mechanisms. On slabs, suitable for modeling the electronic structure of terraces, the calculations predict that oxygen will be adsorbed on top of the surface, whereas on clusters, portions of which can be used to represent steps and kinks, oxygen was calculated to migrate underneath the surface. XPS spectra were calculated for the S (2s) and S (2p) peaks before and after oxidation in order to show that the conventional way of analyzing experimental XPS spectra in terms of known bulk structures can lead to misinterpretations if specific surface structures, as calculated in this study, are neglected. These calculations are beginning to explain the reactivity of galena in terms of the electronic surface structure of this mineral. They are helping us to understand the mechanism of early stages of the adsorption/oxidation process, especially when combined with experimental tunneling spectroscopy at specific sites.
Repeatability of Magnitude Production in Isometric, Hand-Grip Force Estimation: A Working-Memory Approach

Magnitude production has been used in ergonomics research to quantify hand-grip and finger-pinch force exertions. The repeatability of this psychophysical method may be affected by a memory component if the subject must recall multiple, previously performed force exertions. This investigation tested the hypothesis that the number of different to-be-remembered hand-grip force exertions would affect the repeatability of force productions obtained via magnitude production for 12 male students. Four levels of force were examined (20%, 35%, 50%, and 65% of subject's individual maximum) at low and high memory loads (two versus four forces to be remembered concurrently). Amount of force had a significant effect on the variance among a sample of five observations; however, memory load showed no effect on the variance measure. Thus, it is concluded that four forces do not pose a significantly greater memory load than two forces for perceived force in hand-grip magnitude productions.
Adaptive gappy proper orthogonal decomposition for particle image velocimetry data reconstruction

This work presents a novel method for replacing erroneous measurements in digital particle image velocimetry (DPIV) data using an adaptive reconstruction with gappy proper orthogonal decomposition (POD). Previous studies have shown that gappy POD can be used to replace erroneous data with high accuracy. Conventional gappy POD methods employ a spatially constant number of modes for reconstructing the missing information across the entire field. In contrast, the method presented herein proposes a locally adaptive criterion that allows for determination of the optimum number of POD modes required for the reconstruction of each replaced measurement. This reconstruction produces higher accuracy results using more POD modes than with previous POD methods. The new method was compared against commonly utilized techniques for DPIV vector replacement, namely Kriging, bootstrapping and basic interpolation, as well as previously presented POD reconstruction techniques. The results showed that the adaptive gappy POD reconstruction provides higher accuracy and robustness.
Test-enhanced web-based learning: optimizing the number of questions (a randomized crossover trial).

Purpose Questions enhance learning in Web-based courses, but preliminary evidence suggests that too many questions may interfere with learning. The authors sought to determine how varying the number of self-assessment questions affects knowledge outcomes in a Web-based course. Method The authors conducted a randomized crossover trial in one internal medicine and one family medicine residency program between January 2009 and July 2010. Eight Web-based modules on ambulatory medicine topics were developed, with varying numbers of self-assessment questions (0, 1, 5, 10, or 15). Participants completed modules in four different formats each year, with sequence randomly assigned. Participants completed a pretest for half their modules. Outcomes included knowledge, completion time, and module ratings. Results One hundred eighty residents provided data. The mean (standard error) percent correct knowledge score was 53.2 (0.8) for pretests and 73.7 (0.5) for posttests. In repeated-measures analysis pooling all data, mean posttest knowledge scores were highest for the 10- and 15-question formats (75.7 [1.1] and 74.4 [1.0], respectively) and lower for 0-, 1-, and 5-question formats (73.1 [1.3], 72.9 [1.0], and 72.8 [1.5], respectively); P = .04 for differences across all modules. Modules with more questions generally took longer to complete and were rated higher, although differences were small. Residents most often identified 10 questions as ideal. Posttest knowledge scores were higher for modules that included a pretest (75.4 [0.9] versus 72.2 [0.9]; P = .0002). Conclusions Increasing the number of self-assessment questions improves learning until a plateau beyond which additional questions do not add value.
Self-Assembling Peptide-Polymer Hydrogels Designed From the Coiled Coil Region of Fibrin

Biomaterials constructed from self-assembling peptides, peptide derivatives, and peptide-polymer conjugates are receiving increasing attention as defined matrices for tissue engineering, controlled therapeutic release, and in vitro cell expansion, but many are constructed from peptide structures not typically found in the human extracellular matrix. Here we report a self-assembling biomaterial constructed from a designed peptide inspired by the coiled coil domain of human fibrin, the major protein constituent of blood clots and the provisional scaffold of wound healing. Targeted substitutions were made in the residues forming the interface between coiled coil strands for a 37-amino acid peptide from human fibrinogen to stabilize the coiled coil peptide bundle, while the solvent-exposed residues were left unchanged to provide a surface similar to that of the native protein. This peptide, which self-assembled into coiled coil dimers and tetramers, was then used to produce triblock peptide-PEG-peptide bioconjugates that self-assembled into viscoelastic hydrogel biomaterials.
Too little or too much corticosteroid? Coexisting adrenal insufficiency and Cushing's syndrome from chronic, intermittent use of intranasal betamethasone.

To report the puzzling, rare occurrence of coexisting adrenal insufficiency and Cushing's syndrome from chronic, intermittent use of intranasal betamethasone spray. A 62-year-old male was referred to our endocrinology clinic for management of adrenal insufficiency. This previously healthy individual began to experience chronic sinus symptoms in 2007, was treated with multiple ensuing sinus surgeries, and received oral glucocorticoid for 6 months. In the following 5 years, he suffered severe fatigue and was diagnosed with secondary adrenal insufficiency. He could not be weaned from corticosteroid and developed clear cushingoid features. In our clinic, careful inquiry on medications revealed chronic, intermittent use of high-dose intranasal betamethasone since 2008, which was not apparent to his other treating physicians. His cushingoid features significantly improved after holding intranasal betamethasone. Learning points Chronic, intermittent intranasal betamethasone can cause secondary adrenal insufficiency and iatrogenic Cushing's syndrome when used in excess. Topical corticosteroid use should be considered in the differential diagnosis of adrenal insufficiency or Cushing's syndrome.
The psychological growth of women in a short-term inpatient group

This paper identifies ways in which a short-term inpatient group can support psychological growth of women. A four-stage developmental model of women's work in an inpatient group is described. In each stage, women achieve greater comfort in new modes of relating. Women also gain greater appreciation of their interpersonal strengths. In the first stage, women face issues related to autonomy and connection. In the second stage, women focus upon conflictual feelings in relation to authority. In the third stage, women address obstacles to the achievement of satisfying, intimate, peer-based relationships. In the fourth stage, women focus upon the issues of separation and loss that are precipitated by the termination of the group. At each stage, the developmental tasks women perform are contrasted with related but nonidentical tasks performed by men.
Spectral analysis of long EEG sample for comparative purposes

Abstract This report is concerned with practical methods for optimizing and extending the spectral analysis of long EEG samples for comparative purposes. Optimization was accomplished by analyzing only a distributed percentage of the sample and by determining the lowest degree of resolution which would define the data completely. As little as 10% of the sample needed to be analyzed to obtain satisfactorily accurate and reliable estimates. By this means processing time was markedly reduced. Statistical testing indicated that logarithms of spectral density estimates were distributed normally, and this simplified quantitative comparisons. The incorporation of dynamic processing methods made it possible to test samples for their homogeneity and indicated when state changes occurred in the EEG.
Contamination of single-use biopsy forceps: a prospective in vitro analysis.

Abstract Background: It has been suggested that single-use biopsy forceps prevent interpatient transmission of infection during endoscopy. Passage of sterile forceps through the accessory channel of the endoscope may lead to contamination, however, if the endoscope has been inadequately processed. The potential for contamination of single-use biopsy forceps at various stages of endoscope reprocessing was prospectively evaluated. Methods: A total of 50 disposable biopsy forceps were passed through the accessory channels of 10 colonoscopes at the following stages of reprocessing: (1) before use in patients to establish a baseline of high-level disinfection, (2) directly after colonoscopy to confirm contamination with use, (3) after manual cleaning and flushing of the accessory channel to support the claim that manual cleaning significantly decreases bioburden, (4) after manual cleaning and a 2-minute soak in 2% glutaraldehyde to assess for contamination after an inadequate cleaning time, and (5) after manual cleaning and a 20-minute soak in 2% glutaraldehyde. The forceps were then sealed in sterile plastic bags after adding 20 mL of thioglycollate broth medium. The suspension was passed through a 0.2-micron vacuum filter and the filters were cultured. All cultures were incubated more than 48 hours. Results: Biopsy forceps underwent a total of 50 aerobic and 50 anaerobic cultures. Colony-forming units too numerous to count of GI flora, including Escherichia coli, Klebsiella, Pseudomonas , and Clostridium species, grew on 19 of 20 culture plates from biopsy forceps passed through colonoscopes immediately after use. One plate in this group grew 3 colony-forming units of E coli . Persistence of GI flora was noted on 5 of 20 plates after manual cleaning of the colonoscopes. No GI flora were found on forceps after the colonoscopes after soaking in gluteraldehyde for 2 and 20 minutes. Environmental contaminants including diptheroids, Staphylococcus , and Streptococcus species grew on 16 culture plates. Conclusions: (1) Single-use biopsy forceps are highly susceptible to contamination during passage through the accessory channels of improperly cleaned endoscopes. (2) Disinfection of the colonoscopes in this study prevented contamination of the forceps at baseline and after reprocessing. (3) Proper endoscope reprocessing may be the most important factor in preventing biopsy forceps-related interpatient infection. (Gastrointest Endosc 2002;56:209-12.)
Counter observations on the practice of scaling individual ab initio force constants: Vibrational spectra of methylthiirane

Abstract Ab initio Raman and infrared spectra were computed for methylthiirane and compared to the corresponding experimental spectra. An excellent qualitative agreement is present between theoretical predictions and experimental results. When the ab initio force constants were scaled as suggested in the literature, the quality of the resulting theoretical Raman spectrum deteriorated.
Propofol in patients susceptible to malignant hyperthermia: A case report and review of the literature

Propofol is an intravenous (IV) drug recently introduced into the United States for induction and maintenance of anesthesia. In spite of extensive laboratory evaluation, it is not possible to predict all the potential side effects that might be associated with a new drug. Because malignant hyperthermia (MH) remains a serious and potentially life-threatening complication of anesthesia, all new anesthetic drugs should be considered potential triggering drugs until proven otherwise. We report the use of IV propofol for the induction and maintenance of general anesthesia in an MH patient and review the literature on this subject.
X RAYS FROM SOURCES 3C 273 AND M 87.

An x-ray survey of the Virgo region revealed signals from the directions of 3C 273 and M 87. Three other x-ray sources appear in the region scanned, but do not fit any known radio sources. The x-ray flux (1 to 10 angstroms) from the direction of 3C 273 is about 1000 times weaker than from the strongest x-ray source, Sco XR-1. If the source is located at the cosmological distance of 500 megaparsecs, the x-ray luminosity is 7.3 x 10(45) ergs per second. The x-ray luminosity of M87 is 1.5 x 10(43) ergs per second.
Asymptotic expansions of backward equations for two-time-scale Markov chains in continuous time

This work develops asymptotic expansions for solutions of systems of backward equations of time-inhomogeneous Markov chains in continuous time. Owing to the rapid progress in technology and the increasing complexity in modeling, the underlying Markov chains often have large state spaces, which make the computational tasks infeasible. To reduce the complexity, two-time-scale formulations are used. By introducing a small parameter ɛ > 0 and using suitable decomposition and aggregation procedures, it is formulated as a singular perturbation problem. Both Markov chains having recurrent states only and Markov chains including also transient states are treated. Under certain weak irreducibility and smoothness conditions of the generators, the desired asymptotic expansions are constructed. Then error bounds are obtained.
Controlled laser delivery into biological tissue via thin-film optical tunneling and refraction

Due to the often extreme energies employed, contemporary methods of laser delivery utilized in clinical dermatology allow for a dangerous amount of high-intensity laser light to reflect off a multitude of surfaces, including the patient’s own skin. Such techniques consistently represent a clear and present threat to both patients and practitioners alike. The intention of this work was therefore to develop a technique that mitigates this problem by coupling the light directly into the tissue via physical contact with an optical waveguide. In this manner, planar waveguides cladded in silver with thin-film active areas were used to illuminate agar tissue phantoms with nanosecond-pulsed laser light at 532nm. The light then either refracted or optically tunneled through the active area, photoacoustically generating ultrasonic waves within the phantom, whose peak-to-peak intensity directly correlated to the internal reflection angle of the beam. Consequently, angular spectra for energy delivery were recorded for sub-wavelength silver and titanium films of variable thickness. Optimal energy delivery was achieved for internal reflection angles ranging from 43 to 50 degrees, depending on the active area and thin film geometries, with titanium films consistently delivering more energy across the entire angular spectrum due to their relatively high refractive index. The technique demonstrated herein therefore not only represents a viable method of energy delivery for biological tissue while minimizing the possibility for stray light, but also demonstrates the possibility for utilizing thin films of high refractive index metals to redirect light out of an optical waveguide.
Gastric effects of thyrotropin-releasing hormone microinjected into the dorsal motor vagal nucleus in cats

We investigated the gastric acid secretory and motility responses to microinjection of thyrotropin-releasing hormone (TRH) into the dorsal motor nucleus of the vagus (DMV) in anesthetized cats. Gastric acid output was collected every 15 min through a gastric cannula after saline flush and titrated to pH 7.0. Antral and corpus contractions were continuously recorded by extraluminal force transducers. TRH dissolved in 200 nl of saline and microinjected unilaterally into the DMV induced a dose-dependent (50-200 ng) increase in gastric acid secretion. The acid secretory response began in the first 15 min collection and lasted 45 min. TRH frequently increased the force of contractions of the antrum and corpus within one minute of microinjection. The minimal effective dose for eliciting increased motility was lower than for inducing acid secretion. These results demonstrate that TRH acts in the DMV of cats to stimulate gastric acid secretion and contractions.
Bis(2-hydroxybenzylidene)acetone, a potent inducer of the phase 2 response, causes apoptosis in mouse leukemia cells through a p53-independent, caspase-mediated pathway

Bis(2-hydroxybenzylidene)acetone is a potent inducer of the phase 2 response through the Keap1-Nrf2-ARE pathway. This double Michael reaction acceptor reacts directly with Keap1, the sensor protein for inducers, leading to enhanced transcription of phase 2 genes and protection against oxidant and electrophile toxicities. In our efforts to identify potent chemoprotective agents, we found that in rapidly growing murine leukemia cells (L1210) low concentrations (in the submicromolar range) of bis(2-hydroxybenzylidene)acetone markedly increased the activities of NAD(P)H:quinone acceptor oxidoreductase 1 (NQO1) and glutathione reductase, and the levels of total glutathione, three markers of the phase 2 response. In contrast, at high concentrations (in the micromolar range) the same compound caused G2/M cell cycle arrest and apoptosis. Importantly, a mutant L1210 cell line (Y8), selected for resistance to deoxyadenosine and lacking expression of p53 protein, was considerably more sensitive to the apoptotic effects of bis(2-hydroxybenzylidene)acetone. When caspase activities were evaluated in cell-free extracts prepared from treated wild type or mutant L1210 cells, the activities of caspase-3, the terminal caspase in the cascade leading to apoptosis, and caspase-10 were found to be markedly elevated. The activities of other caspases measured, caspase-1, -6 and -8, were not appreciably affected. Thus, both induction of the phase 2 response and p53-independent, caspase-3-mediated apoptosis could act cooperatively in chemoprotection. The concentration-dependent differential effects on these two pathways should be carefully considered in mechanistic explanations and strategic designs.
Simulations of Discrete Quantized Gravity

According to Einstein's general theory of relativity, the geometric properties of space are related to the distri bution of matter and energy in the universe. In a quan tum-mechanical theory of gravitation the geometry of space and time is subject to strong fluctuations at ex tremely short distances. Traditional methods, based on perturbation theory, have difficulties in dealing with these highly nonlinear fluctuations. Discretized models for quantum gravity introduce a fine space-time mesh, and attempt to solve the fundamental equations using large-scale Monte Carlo simulations. We discuss some preliminary results obtained by applying these meth ods to a model for pure quantum gravity involving up to 983,040 edges in a four-dimensional lattice. A nu merical solution to these equations could provide an answer to some basic cosmological questions.
On the equation of state of polymer solutions

The theory formulated for single and multicomponent systems is applied to polymer solutions. This follows earlier investigations on mixtures of low molecular weight compounds and a binary compatible polymer mixture. The requisite analysis of the polymer constituents, namely polyisobutylene and poly(dimethylsiloxane) shows good agreement between experiment and theory. Similar conclusions apply to the solvents, namely cyclohexane, benzene and hexa(methyl disiloxane). For the solutions, the theory makes predictions at elevated pressures, based on the equation of state of the constituents and low pressure experimentation for the mixtures. Satisfactory results obtain in this manner with deviations increasing with temperature and pressure (maximally 1 kbar). At low pressures, the agreement between experiment and theory is good for all temperatures and compositions.
Metal-on-conventional Polyethylene Total Hip Arthroplasty Bearing Surfaces Have a Higher Risk of Revision Than Metal-on-highly Crosslinked Polyethylene: Results From a US Registry

Background Although studies have reported lower radiological wear in highly crosslinked polyethylene (HXLPE) versus conventional polyethylene in total hip arthroplasty (THA), there is limited clinical evidence on the risk of revision of these polyethylene THA bearing surfaces.
Identification of Individual Drug Crystals on Paper Currency Using Raman Microspectroscopy

Abstract Drug consumption, and the industry that supports it, have been targets of law enforcement efforts for several decades. Recently, several countries have allowed the seizure of paper currency associated with the drug trade for evidentiary purposes. Mass spectrometric methods are most commonly used to detect the presence of illicit drugs on paper currency. Unfortunately, these methods are destructive and the evidence is no longer available for re‐analysis by other laboratories. Raman microspectroscopy provides an alternative for non‐invasively analyzing drug crystals on banknotes. This study shows that it is possible to detect and identify single drug crystals in a heterogeneous mixture. Samples were composed of two drug surrogates: isoxsuprine and norephedrine, and two common excipients: benzocaine and lidocaine. It is possible to detect and identify individual crystals on both microscope slides and paper currency. Spectra acquired from crystals on United States paper currency suffer from significa...
Does Taglit-Birthright Israel Foster Long-Distance Nationalism?

Taglit-Birthright Israel has brought hundreds of thousands of diaspora Jewish young adults on tours of Israel. Drawing on data from a large-scale program evaluation, we ask how the program affects participants’ feelings of homeland attachment and political views on contentious homeland issues. North Americans who traveled to Israel with Taglit between 2010 and 2012 were surveyed together with a comparison group of applicants to the program who did not participate. In multivariate analysis, Taglit sharply increases feelings of connection to Israel but has no effect on attitudes concerning the future of Jewish settlements in the West Bank. The program modestly increases scores on a “favorability” scale and modestly increases opposition to a possible division of Jerusalem in a future peace deal. In contrast to Benedict Anderson's theory of long-distance nationalism, the findings suggest that feelings of homeland connection can be fostered without triggering ethnonationalist attitudes associated with the poli...
Pressure Transient Testing With A Partially Penetrating Well In A Two-Layer Reservoir

An analytic solution has been derived to investigate the transient pressure response of two-layer reservoirs with cross-flow. Results of the analytic method have been verified using a finite-element model and they reveal important details of pressure transient behavior such as the limiting conditions for detecting a multilayer situation. A procedure has been developed to evaluate the permeability of the producing layer as well as that of the second layer. The method can be applied to both pressure buildup and interference well tests. As has been previously shown from earlier numerical techniques, the early-time response or such a two-layer reservoir producing from a fraction of the thickness of one of the layers closely follows the behavior of a single-layer case. An inflection point in the pressure response can be expected under certain circumstances, and this provides important data. At large times the system behaves like an equivalent homogeneous reservoir.
Cognitive transmit beamforming from binary link quality feedback for point to point MISO channels

Transmit beamforming is an effective way to enhance transmission range and quality of service while limiting interference to other co-channel systems, thus facilitating easier coexistence. Transmit beamforming requires channel state information to be acquired at the receiver and fed back to the transmitter. This in turn requires a relatively complex receiver, agreement on a training protocol, and a cold-start training period during which no payload is sent to the receiver. This article explores how the transmitter can learn to beam-form on-the-fly from very low-rate channel quality indicator bits fed back from the receiver, while transmitting payload at the same time. The setup is tuned to low-latency scenarios where the receiver has limited capabilities, and is paired up opportunistically with the transmitter. Leveraging the Analytic Center Cutting Plane Method (ACCPM), an online channel correlation matrix learning method is developed, based on one-bit Signal to Noise Ratio (SNR) feedback from the receiver. The method is shown to asymptotically achieve the maximum possible SNR at the receiver (attained with perfect knowledge of the correlation matrix), starting from no channel state information. A Maximum Likelihood (ML) formulation is also developed for the case when there are feedback errors, and conditions for its asymptotic convergence are derived.
Conformational Changes in the Lac Repressor Protein Effect DNA Loop Energetics and Topology

DNA looping mediated by the Lac repressor protein is a classic exemplar for understanding protein-DNA interactions and allosteric mechanisms in gene regulation. When the repressor protein binds to two distant operator sites on substrate DNA, it causes the formation of DNA loops. Most of the previous study of this system has focused on either the properties of the DNA loop created by the protein-DNA interaction or seeks to explain the possible conformational changes of the protein itself. Here we take a combined approach by considering the effects of protein deformation on the topology and energetics of the induced looped-DNA. We begin by creating a collection of 3D atomic coordinate models of the protein to simulate the structural fluctuation consistent with earlier studies. By incrementally rotating segments of the protein about likely sites of flexibility these new models provide a large distribution of constraint parameters for the generation of looped-DNA coordinates. We then employ a novel approach to obtain minimum energy looped structure whereby the potential energy of elastic deformation is optimized. In this way we are able to describe energy landscapes that provide clues to how variations in protein structure contribute to DNA loop stability and topology.
Pediatric periorificial dermatitis: clinical course and treatment outcomes in 222 patients.

Background Periorificial dermatitis (POD) is a rosacea-like papulopustular facial eruption most commonly reported in young adult women. Although POD has been reported in children as young as 6 months of age, there are limited data on the diagnosis and management of POD in pediatric cases. Methods All children diagnosed with POD at the Dermatology Clinic at the University of North Carolina at Chapel Hill between June 2002 and March 2014 were included in the current study. Information related to demographics, associated risk factors, treatment prescribed, adverse effects, and response to treatment were obtained from a retrospective analysis of medical records. Results Of the 222 children identified, 55.4% were female, 62.2% Caucasian, and the average age at presentation to the clinic was 6.6 years. Although the etiology of POD remains uncertain, 29.3% reported a past medical history of atopic dermatitis, 14.9% reported a history of asthma and 58.1% reported a history of steroid use prior to POD onset. Fifty-nine percent were seen at a clinic visit for follow-up at an average of 3.8 months. Treatment often involved combining oral azithromycin with topical metronidazole or sodium sulfacetamide lotion. Of the patients with documented follow-up, 71.8% experienced complete resolution of POD. Recurrence of POD occurred in children dependent on inhaled steroids or nebulizers. Adverse effects were minimally noted, but included pigmentary changes (1.8%), worsening of symptoms (1.8%), gastrointestinal upset (0.9%), irritant dermatitis (0.9%), and xerosis (0.5%). Conclusion This study discusses the clinical diagnosis and management of POD in pediatric cases.
Observation of resonantly enhanced degenerate four-wave mixing in doped alkali halides.

We describe the first reported observation of resonantly enhanced phase conjugation through degenerate four-wave mixing (DFWM) in doped alkali halides. We also describe the first reported quantitative comparison of the resonant DFWM process in the infrared with the theory of Abrams and Lind [Opt. Lett. 2, 94 (1978); 3, 205 (1978)]. The comparison for small values of α0L is shown to be excellent. For α0L in excess of 3, experiment and theory diverge because of pump attenuation by the resonant medium.
Superiority of Amphotericin over Nystatin in Thayer-Martin Medium

Vaginal and cervical specimens taken for the detection of gonorrhea frequently contain Candida albicans . Thayer-Martin medium containing nystatin (VCTN) is unsatisfactory because nystatin fails to selectively inhibit C. albicans . Thayer-Martin medium containing no nystatin was prepared with varying concentrations of amphotericin (VCTA) added, and this latter medium was compared with VCTN for its ability to selectively inhibit varying numbers of C. albicans . The effect of amphotericin on the recovery of varying numbers of Neisseria gonorrhoeae was also studied. VCTN failed to inhibit 10 1 to 10 6 C. albicans . VCTA suppressed growth of up to 10 6 C. albicans . The optimal concentration of amphotericin B appeared to be 100 μg/ml. VCTA containing 100 μg of amphotericin B per ml (VCTA 100) was not inhibitory for N. gonorrhoeae when a dense population was applied with a replicator. However, it was slightly inhibitory when 10 1 to 10 2 N. gonorrhoeae were applied over the entire surface of an agar plate, although the colony count on VCTA 100 was more than 50% of the counts on chocolate agar and 75% of the counts on VCTN. These properties of VCTA 100, when stored at 4 C, were stable for up to 2 weeks.
The Cystic Fibrosis Foundation Therapeutics Development Network: A National Effort by the Cystic Fibrosis Foundation to Build a Clinical Trials Network

Clinical trial networks that provide centralized coordination of multicenter studies have become critical to the advancement of clinical research. We describe a national effort by the U.S. Cystic Fibrosis Foundation (CFF) to build a network to evaluate therapeutic interventions in cystic fibrosis (CF). The CFF Therapeutics Development Network (CFF TDN) was established in 1998 and has since promoted the safe and efficient conduct of multiple clinical trials. The orphan disease setting presents many challenges for clinical research, and the CFF TDN has met these challenges by advancing CF outcome measures development and fostering innovative approaches toward the design and analysis of clinical trials.