cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of interface structure on dislocation glide behavior in nanolaminates

The ultra-high strength of nanolaminates arises from the effect of the fine layering on dislocation motion. Using atomistic simulations, we investigate the effect of the interface structure on the behavior of an edge dislocation driven to glide within a nanolayer of a nanolaminate. Three classes of interface structures are studied, including Cu/Nb or Cu/Cu incoherent interfaces and Nb/Nb coherent interface. Glide behavior is jerky when the interface is incoherent and composed of discrete misfit dislocation arrays. The resistance to glide is non-uniform among parallel glide planes, where planes with intersection lines coinciding with misfit dislocation lines experience greater resistances than those that do not. Interfaces containing misfit dislocations, which extend from the interface into a glide plane in the layer, severely obstruct glide, causing the dislocation to transfer to a parallel plane. Coherent interfaces, while posing the least resistance to initiate and promote smooth glide, lead to strain hardening.
Sleep medication use and risk of fractures in breast cancer survivors.

Sleep problems are more common in breast cancer survivors than those without a cancer history. Our goal was to examine the risk of fractures among breast cancers survivors who used prescription sleep aids. We conducted a retrospective cohort study of 21,346 adult women diagnosed with stage 0–III breast cancer between 2009 and 2016 and followed them through 2017. We examined person-year rates of fractures by sleep medication use and calculated adjusted hazard ratios (HR) and 95% confidence intervals (CI) with Cox proportional hazards models using time-dependent variables for sleep medications and covariate medications (antidepressants, anti-anxiety medications, and bisphosphonates) adjusted for demographics, comorbidities, and tumor characteristics and cancer treatments. The sleep medication use was common (40%) in breast cancer survivors and was associated with a 33% increased risk of fractures (adjusted HR = 1.33, 95% CI: 1.20–1.49). Further, in a sensitivity analysis based on new use of sleep medication, the fracture risk was even stronger (adjusted HR = 1.44, 95% CI: 1.26–1.64). Given the high use of sleep medications and the high risk of fractures in breast cancer survivors, this study suggests that non-pharmacologic management of sleep problems might be considered as alternative therapy.
AFRICAN BITTER LEAF EXTRACT EFFECT ON EPITHELIUM THICKNESS OF SEMINIFEROUS TUBULES IN WISTAR RATS WITH DIABETES MELLITUS

Introduction: Diabetes mellitus (DM) is a metabolic disease that can cause complications in the form of damage to male reproductive organs, such as decreased sperm motility and cell count, impaired spermatogenesis, and erectile dysfunction. A measurement that can be done to detect male reproductive disorders is to measure the thickness of the seminiferous tubule epithelium. Herbal medicines can be used to support treating diabetes. Studies have claimed that African bitter leaf helps in treating DM and its complications. Purpose: This study aims to determine the effect of African bitter leaf extract on epithelium thickness of seminiferous tubules in rats with DM. Method: True Experimental with Post-Test Only Control Group Design using Rattus norvegicus. Rats were divided into five groups, with six rats in each group. Rats were administered with a single dose of alloxan 150 mg/kg BW/IP. Group K is diabetic rats given glibenclamide 0,63 mg/kg BW. Group P0 are diabetic rats given CMC 0,1% 0,7 ml. Group P1 are diabetic rats given African bitter leaf extract 100 mg/kg BW. Group P2 are diabetic rats given African bitter leaf extract 200 mg/kg BW. Group P3 are diabetic rats given African bitter leaf extract 400 mg/kg BW. Treatments were given with oral gavage for 14 days. Rats were dissected, and their testis was made as histological slides. Results are statistically tested with ANOVA. Results: The average epithelium thickness from group K are 79,61 μm, group P0 are 59,96 μm, group P1 are 71,87 μm, group P2 are 67,31 μm, group P3 are 63,95 μm showed significant result (p=0,000). Conclusions: African bitter leaf extract affects epithelium thickness of seminiferous tubules, with group K, shows the best result, followed by group P1.
Investigating the Relationship Between Gang Membership and Carrying a Firearm: Results from a National Sample

While there is evidence that gang membership impacts an individual’s gun carrying proclivities, existing research has largely focused only on males and at-risk youth. The present study investigates the role of gang membership, peer gang membership, and delinquency on whether individuals carry a firearm using data from the National Longitudinal Survey of Youth 1997. Carrying a firearm was associated with involvement in delinquency, peer gang membership, and respondent gang membership. The association between gang membership and carrying a firearm weakened with age. Few significant differences across categories of sex and race emerged suggesting that the relationship between gang membership and carrying a firearm is equivocal across these groups.
Evidence for a Relative Vitamin B6 Deficiency in Pregnancy and Some Disease States

Publisher Summary This chapter reviews the evidence indicative of a relative vitamin B 6 deficiency in pregnancy and in some patients with miscellaneous diseases. Evidence for the presence of a relative vitamin B 6 deficiency in pregnancy and various other conditions is based exclusively on laboratory examinations. Tests that are useful in the valuation of vitamin B 6 metabolism include those concerned with the urinary excretion of intermediary metabolites following oral adminostration of tryptophan, preferably before and after the administration of pyridoxine. The blood levels of other vitamin B6-dependent enzymes—for example, serum glutamine-oxalacetic transaminase—can also give information as to the availability of vitamin B 6 in clinical subjects. Similarly, the urinary excretion of 4-pyridoxic acid can be used to judge the amount of metabolized vitamin B 6 . Measurements of the total B 6 content and its enzymatically active fractions, pyridoxal phosphate and pyridoxamine phosphate, in various components of the circulating blood will reflect the amount of available vitamin B 6 in the body.
RTSJ Memory Areas and Their Affects on the Performance of a Flight-Like Attitude Control System

The two most important factors in improving performance in any software system, but especially a real-time, embedded system, are knowing which components are the low performers and knowing what can be done to improve their performance. The word performance with respect to a real-time, embedded system does not necessarily mean fast execution, which is the common definition when discussing non real-time systems. It also includes meeting all of the specified execution dead-lines and executing at the correct time without sacrificing non real-time performance. Using a Java prototype of an existing control system used on Deep Space 1[1], the effects from adding memory areas are measured and evaluated with respect to improving performance.
POSITIVE MAGNETORESISTANCE IN QUASI-ONE-DIMENSIONAL CONDUCTORS

We present here a simple qualitative model that interpolates between the high and low temperature properties of quasi-1D conductors. At high temperatures we argue that transport is governed by inelastic scattering whereas at low temperatures the conductance decays exponentially with the electron dephasing length. The crossover between these regimes occurs at the temperature at which the elastic and inelastic scattering times become equal. This model is shown to be in quantitative agreement with the organic conductor $TTT_2I_{3-\delta}$. Within this model, we also show that on the insulating side, the positive magnetoresistance of the form $(H/T)^2$ observed in $TTT_2I_{3-\delta}$ and other quasi-1D conductors can be explained by the role spin-flip scattering plays in the electron dephasing rate.
Intermediate Optics in Nipkow Disk Microscopes

The confocal laser scanning scanning optical microscope (LSCM) has the major advantages that it yields a very short depth-of-focus, its transverse definition and the contrast of the image are better than with a standard microscope, the device is very well-suited for optical cross-sectioning, and with the use of a laser beam, the intensity of illumination can be very high. At the same time, it is possible to choose the wavelength of the illumination very easily [Wilson et al, 1984].
Doppler tolerant and detection capable polyphase code sets

In this paper, sections of P3/P4 polyphase codes are concatenated to construct a new class of polyphase code sets. They are defined by closed-form mathematical expressions, from which code sets can be easily generated with properties dependent on the values of the key design parameters. The phases of the resulting codes need not have any degree of uniformity. However, if desired, then at the cost of slightly degraded correlation and Doppler properties, the phase values of the generated code sets can be quantized to have equally spaced phases on the unit circle. The correlation and Doppler properties of several design examples of polyphase code sets are examined in terms of the autocorrelation, cross-correlation, and ambiguity functions. For comparison with existing quadphase code sets, an example of the proposed code sets is quantized to quadphase. The correlation properties of the resulting quadphase code set are found to be similar but slightly inferior to those of the existing code sets, while they are found to be superior in terms of Doppler tolerance and detection capability. In contradistinction to the proposed sets with both Doppler tolerance and detection capability, the existing code sets are, at best, moderately Doppler tolerant, while they are entirely lacking Doppler detection capability. The receiver is modeled as a matched filter that is decomposed into two parallel parts, the outputs of which allow for the detection of the target’s radial direction in addition to its radial speed. For additional improvement in the Doppler properties at the cost of a slight signal-to-noise ratio (SNR) loss and small degradation in the correlation properties, the two parts of the decomposed matched filter can be extended in either direction.
Online social networks and leadership : Implications of a new online working environment for leadership

Purpose – The purpose of this paper is to examine the role of online social networks in experiencing a change in working environment of today's leaders. Design/methodology/approach – The study's participants were managers, directors and CEOs working in different organizations (including Fortune 500 companies) in the USA, the UK, Germany, France, Russian Federation, Australia and China. The data were collected through structured surveys delivered through LinkedIn to the managers, directors and CEOs. A total of 115 matched questionnaires were returned. Statistical analysis, using STATA software, was conducted to assess the research results. Findings – The results indicate that the importance of online social networking environment is growing. Furthermore the study shows that online social networks are more useful for participative and consultative leadership style on social networking platforms than for directive leadership style. A higher number of activities on social networks by leaders is positively ass...
El rol del Estado en el desarrollo social y la Reforma de la previsión en Chile y EE.UU

This paper discusses historical and sociological information concerning social legislation in Chile. It points out that privatization of pensions imposed in 1980, transferred under the control of a small group of entrepreneurs and businessmen valuable social resources. This change facilitated the establishment of neo-liberal capitalism and reduced the role of the State in key functions necessary for social well-being. While Chile looks now for new changes in the area of workers' pensions, the United States debates privatization of Social Security established in 1935. The Chilean experience, in this sense, appears contrary to a system based on solidarity and community building proposed by Socio-Economics.
Lunar dust transport by photoelectric charging at sunset

The motion of dust grains from a photoelectrically charged object at the moon's sunset terminator is studied with the aid of a simple model. It is shown that sunlit objects ranging in size from less than 0.01 cm to 5 cm in radius are responsible for the levitation of dust grains to heights of observed horizon glow. The transverse displacement of these grains is observed to be at least twice their maximum altitude, so that fitting the latter to horizon glow implies horizontal particle ranges typically 6 to 60 cm. Detachment of these grains from the sunlit areas takes place mainly along the contracting sunlight boundaries as the areas shrink during sunset. A high ratio of intergrain adhesion force to dust-grain weight is essential for the occurrence of horizon glow and significant dust transport from the subcentimeter sized sunlit areas.
Dynamic Control of Radiative Surface Properties With Origami-Inspired Design

Thermal management systems for space equipment commonly use static solutions that do not adapt to environmental changes. Dynamic control of radiative surface properties is one way to respond to environmental changes and to increase the capabilities of spacecraft thermal management systems. This paper documents an investigation of the extent to which origami-inspired surfaces may be used to control the apparent absorptivity of a reflective material. Models relating the apparent absorptivity of a radiation shield to time-dependent surface temperatures are presented. Results show that the apparent absorptivity increases with increasing fold density and indicate that origami-inspired designs may be used to control the apparent radiative properties of surfaces in thermal management systems.
The Social Character of Children's Television Viewing

This study considers some social dimensions of children's television viewing. Review of the literature shows a paucity of data on the subject and a tendency to focus research attention on television rather than children. This study is grounded on symbolic interactionist principles and utilizes naturalistic observation in data collection. Specimens of viewing behavior are offered and an argument for sociologically grounded investigation is made.
Use of PET for Monitoring Cancer Therapy and for Predicting Outcome

PET with the glucose analog (18)F-FDG is increasingly used to monitor tumor response in patients undergoing chemotherapy and chemoradiotherapy. Numerous studies have shown that (18)F-FDG PET is an accurate test for differentiating residual viable tumor tissue from therapy-induced fibrosis. Furthermore, quantitative assessment of therapy-induced changes in tumor (18)F-FDG uptake may allow the prediction of tumor response and patient outcome very early in the course of therapy. Treatment may be adjusted according to the chemosensitivity and radiosensitivity of the tumor tissue in an individual patient. Thus, (18)F-FDG PET has an enormous potential to reduce the side effects and costs of ineffective therapy. This review focuses on the practical aspects of (18)F-FDG PET for treatment monitoring and on how to perform a quantitative assessment of tumor (18)F-FDG uptake in clinical studies.
Magnetically Powered Flexible Metal Nanowire Motors

Fuel-free magnetically driven propulsion of flexible Au/Ag/Ni nanowires, with a gold ‘head’ and nickel ‘tail’, linked by a partially dissolved and weakened silver bridge, is described. The flexible bridge facilitates the cyclic mechanical deformations under an external rotating magnetic field. Under such a field the nickel segment starts to rotate, facilitating the rotation of the gold segment at a different amplitude, hence breaking the system symmetry and inducing the movement. Forward (‘pushing’) and backward (‘pulling’) magnetically powered locomotion and a precise On/Off motion control are achieved by tailoring the length of the nickel and gold segments and modulating the magnetic field, respectively. Efficient locomotion in urine samples and in high-salt media is illustrated. The new magnetic nanowire swimmers can be prepared in large scale using a simple template electrodeposition protocol and offer considerable promise for diverse practical applications.
Cuticular lipids of adult fleshflies, Sarcophaga bullata

Abstract A major component of the adult fleshfly, Sarcophaga bullata , cuticular lipid is hydrocarbon. There are on average about 100 μg. of hydrocarbon per fly; however, only about one-third of the hydrocarbon is extractable by hexane washing the flies just after the pupal-adult ecdysis. Seven days after adult emergence the cuticular hydrocarbons are nearly all extracted by hexane washing. Some high molecular weight hydrocarbons are absent in newly emerged adults but are clearly present in low, but measurable, amounts in older adults. The major hydrocarbons are n -alkanes and monomethylalkanes with minor amounts of other branched alkanes, monoenes, and alkadienes. Every possible odd-numbered monomethylalkane was identified through the use of mass fragmentation chromatography. Even-numbered monomethylalkanes are strikingly absent.
Multislice, dual-imaging sequence for increasing the dynamic range of the contrast-enhanced blood signal and CNR of myocardial enhancement at 3T.

Purpose To develop a multislice, first-pass perfusion imaging sequence for increasing the effective dynamic range of the contrast-enhanced blood signal and the contrast-to-noise ratio (CNR) of myocardial wall enhancement. Materials and Methods A hybrid echo-planar imaging (EPI) pulse sequence was modified to acquire data for both the arterial input function (AIF) and the myocardium, using two different saturation-recovery time delays (TDs) and spatial resolutions, after a single saturation pulse. Five healthy subjects were scanned at 3T in three short-axis levels of the heart per heartbeat during passage of a high-dose bolus of contrast agent. The T1-weighted signal-time curve of the blood was converted to AIF using empirical conversion tables derived from phantom experiments. Results In all subjects the calculated AIF was consistently less distorted and higher for the short-TD protocol than for the long-TD protocol (peak concentration: 5.0 ± 1.0 mM vs. 3.0 ± 0.6 mM; P < 0.01). A combination of EPI, long TD, high-dose bolus of contrast agent, and 3T imaging yielded relatively strong peak enhancement in the myocardium (CNR = 11.9 ± 3.3). Conclusion Our dual-imaging approach at 3T seems promising for acquiring both a relatively accurate AIF and a high CNR of myocardial wall enhancement in multiple slices per heartbeat. J. Magn. Reson. Imaging 2006. © 2005 Wiley-Liss, Inc.
A Comparison of Three Methods for Measuring Mixing-Layer Height

Abstract Temperature profile, lidar and sodar results for determination of mixing-layer heights during October 1977 are compared. While the overall agreement was good, systematic differences do appear, particularly in early morning and late afternoon between lidar and sodar results, when the lidar values are consistently higher than the sodar. Temperature profile values are consistently lower than the other two methods. These differences are due to the slightly different behavior of the sensed variables near the capping inversion. Aerosols and particulates mix to larger heights than the top of the adiabatic temperature profile, while temperature fluctuations exhibit an increase at a height above the top of the adiabatic temperature profile but below the maximum height of particulate mixing.
Acceleration of change: Catalysts in brief therapy

Abstract Brief therapy may be evolving into a fundamentally new approach to psychological intervention, best described as acceleration of change. A selective literature review examines four catalysts that may facilitate acceleration. Planning involves rapid initial assessment, focus/goal clarification, and treatment selection. Collaboration entails rapidly building and maintaining a therapeutic alliance. Timing includes rapid initial intervention, followed by control of number, frequency, and duration of therapy sessions; treatment stages; intersession activity; and intermittency. Empowerment entails encouragement of self-directed psychological growth. Future progress will require advances in theoretical integration, empirical research, and cost containment.
Structural relaxation and conductivity relaxation in glassy ionics

The coupling model was proposed to describe relaxations in complex correlated systems of which ionic conducting glass is a special case. The model is capable of explaining both the structural and the conductivity relaxations of ionic conducting glasses. Recent results from Monte Carlo simulations of ionic motion in glasses are shown to be in total agreement with the predictions of the coupling model. Experimental data from nuclear spin relaxation in poor ionic conductors and quasielastic neutron scattering in fast ionic conductors provide also strong support for the validity of the coupling model. A correlation between the stretch exponent of conductivity relaxation with the decoupling iondex proposed by Angell is discussed in the light of the coupling model
Scalability studies and performance comparison of vehicles with two different suspensions

In this paper, performances of two vehicles with different suspension systems are compared. One of the vehicles has six wheels and six standard independent suspensions, which move along vehicle body lift coordinate. The other vehicle has four wheels and four independent suspensions to form an A-frame system. Each of the four suspensions can have large rotations around the join joining the vehicle body and the suspension. Based on kinematics analysis, the A-frame suspension vehicle has advantages in vertical position adjustment, stability for side slope surface crossing, hill climbing and descending, cornering, and isolation of body from acceleration and braking. The standard suspension vehicle has advantages in constant wheelbase, no sideslip while vehicle body changing its positions, simplicity in structure and mathematical modeling. According to dynamic response analysis for passive mode, the A-frame vehicle is better in handling and clearance maintenance and the standard independent suspension vehicle is better in ground irregularity isolation and traction force maintenance. This paper also introduces the applications of isometric charts for standard suspension vehicles. Each chart can be used to select spring and damper pairs for a group of standard suspension vehicles, which have different inertia and geometry properties.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Regulation of DNA replication by homopurine/homopyrimidine sequences.

The simple repeating homopurine/homopyrimidine sequences dispersed throughout many eukaryotic genomes are known to form triple helical structures comprising three-stranded and single-stranded DNA. Several lines of evidence suggest that these structures influence DNA replication in cells. Homopurine/homopyrimidine sequences cloned into simian virus 40 (SV40) or SV40 origin-containing plasmids caused a reduced rate of DNA synthesis due to the pausing of replication forks. More prominent arrests were observed in in vitro experiments using single-stranded and double-stranded DNA with triplex-forming sequences. Nucleotides unable to form triplexes when present in the template DNA or when incorporated into the nascent strand prevented termination. Similarly, mutations destroying the triplex potential did not cause arrest while compensatory mutations restoring triplex potential restored it. These and other observations from a number of laboratories indicating that homopurine/homopyrimidine sequences act as arrest signals in vitro and as pause sites in vivo during replication fork movement suggest that these naturally occurring sequences play a regulatory role in DNA replication and gene amplification.
A work authorization format for removable partial dentures

A work authorization for a removable partial denture differs considerably from that given for the complete or fixed partial denture. Included in this article is a suggested format that is effective and easily understood. A surveyed diagnostic cast should be submitted with the various components carefully located and outlined. When this is accomplished by concise, written data, a work authorization meets both legal and professional requirements.
830 nm emission in sodium vapor

We demonstrate that the intriguing 830 nm coherent emission, which is observed when sodium vapor is pumped with a high-power pulsed laser tuned near the 3S→4D two-photon transition, is due to an axially phase-matched six-wave mixing process. This conclusion is based upon the observation of emission near 584 nm, which is coupled to the 830 nm emission in the six-wave mixing process: ω1+ω2=2ωL−ω4D→4P−ω4P→3D. In addition, we have observed coherent emission near 1.16 μm, which is due to an analogous process involving cascade through the 4S (as opposed to the 3D) state. We calculate the wavelengths of all photons involved in these processes using the standard formulas of parametric wave-mixing theory, and show that they can be predicted to within experimental uncertainties. Finally we report observations of significant blue shifts of the 830 nm and 1.16 μm emissions in a mixed sodium-potassium vapor. These shifts can be readily understood by considering the effect of the potassium on the frequency-dependent refractive index of the vapor. Due to these results, other recent interpretations of the 830 nm emission as stimulated excimer emission on the Na2 13Σg+→13Σu+band must now be rejected.
Paleohydrologic analysis of a late Carboniferous fluvial system, southern Morocco

Differential weathering of paleosurfaces in upper Carboniferous sandstone of southern Morocco has exposed arcuate ridges and swales that record point-bar accretionary events. From the point-bar ridges and swales, paleohydraulic and paleogeographic data have been gathered that define an array of late Carboniferous rivers with moderate discharges calculated to be from 130 to 565 m 3 /sec. The broad sinuous channels flowed toward the east-southeast; the distance from the source terrain to the sea was about 100 km. Channel slope was approximately 0.16 m/km.
European Society of Hypertension and European Society of Cardiology Guidelines and the Muted Enthusiasm for Home Blood Pressure Monitoring

The recent, brief summary review, Hypertension Guidelines: More Challenges Highlighted by Europe, effectively highlights some weaknesses in the European guidelines for the management of arterial hypertension.1,2 The editors, however, missed an opportunity to restate the importance of home blood pressure monitoring (HBPM). Patients with hypertension would be better served if these guidelines had not muted enthusiasm for HBPM, as the editors stated, but placed more emphasis on its use. In 2008, the American Heart Association/American Society of Hypertension/Preventive Cardiovascular Nurses Association joint statement …
Arsenic—A classic example of chemophobia

Abstract This review examines the evidence which has served as the basis for the classification of arsenic as a carcinogen. The difficulties encountered in examining multivariant systems and choosing a single variant (in this case arsenic) as the causative agent are discussed. The inability to induce tumors in animal systems by the administration of arsenicals and the nonoccurrence of excess cancer deaths in a number of locations in the united states where arsenic-rich drinking waters are consumed are noted. Finally, the question is raised whether epidemiological data, alone, with no demonstration of experimental carcinogenesis, should serve as the basis for the classification of a substance as a carcinogen.
The Organic Metallic State1

Abstract The development of the organic metallic state is traced from our original synthesis and study of TTF-TCNQ to the new conductor HMTSF-TCNQ, the first organic substance which remains metallic as T → 0.
Lifetime-based optical sensing of pH using resonance energy transfer in sol—gel films

Abstract We describe the fabrication and testing of an optical pH sensor based on fluorescence lifetime measurements and sol-gel technology. These sensors are potentially suitable for use with simple laser-diode light sources. The sensor is based on the phenomenon of fluorescence resonance energy transfer (FRET) from a pH-insentive donor to a pH-sensitive acceptor. The pH-dependent increase in the bromothymol blue (BTB) acceptor absorbance results in increased energy transfer, reducing the lifetime of the Texas Red Hydrazide (TRH) donor. The lifetimes are measured by the phase and modulation of the emission, relative to the modulated incident light, and are found to be insentive to the total signal level and fluctuations in light intensity. However, the present sensors are sensitive to salt concentration and/or ionic strength. Importantly, this sol-gel sensor is not fragile: it provides stable readings for days and can be repeatedly autoclaved without loss of sensitivity to pH. The use of FRET as the pH transduction mechanism can be reliably extended to longer wavelenghts, and allows the future use of laser-diode excitation sources. Such simple and robust sensors have numerous potential applications in analytical and clinical chemistry.
Novel targets for antibiotics

The rapid and extensive emergence of antibiotic resistant bacteria has resulted in a clear cut need to discover new antibiotics. Because of the many years of extensive screening, it is likely that most of the easy discoveries have been made and, therefore, new targets for antibiotics and new screening strategies for their discovery need to be developed. The approaches described in this overview are divided into several categories that are associated with different probabilities for a successful discovery. Approaches that are more likely to be successful include a continuation of classical discovery tactics including the chemical modification of extant structures, the use of new screens for classical targets (for example, the use of the enzyme DNA gyrase to discover new 4-fluoroquinolones), and the development of novel methods of drug delivery. These approaches, however, are likely to yield small incremental advances. More novel approaches should yield radically new chemical structures, however, the likeli...
Circadian rhythm of gastric acid secretion in men with active duodenal ulcer

Twenty-one men with active duodenal ulcer underwent hourly gastric acid and 4-hourly plasma collections under fasting conditions. A statistically significant circadian rhythm was demonstrated for the group by population-mean cosinor analysis, a statistical technique designed for time-dependent measurements, for the 24-hr acid secretory output but not for plasma gastrin concentration. These findings are compatible with the interpretation that the circadian rhythm of unstimulated gastric acid secretion, here observed in most patients of the active ulcer group and previously reported for a group of healthy subjects, does not depend critically upon a circadian-rhythm change in plasma gastrin. Chronobiologic statistical techniques add an important quantitative element to the time-dependent measurement of gastrointestinal function of which one example is gastric acidity, with high rates occurring during the evening and low ones in early morning.
Polycystin-2 Contains an Unpaired EF-hand Motif which May Serve as a Ca2+-Sensitive Regulator of Polycystin-2 Channel Activity

Autosomal dominant polycystic kidney disease (ADPKD) is the most common, monogenic cause of kidney failure in humans. Most cases of ADPKD are linked with mutations in polycystin-1 (PC1) and polycystin-2 (PC2). PC2 is a calcium (Ca2+) permeable channel in the TRP channel family. Deletion of the C-terminus of PC2 alters Ca2+-signaling; the most common pathogenic mutations in PC2 are premature truncations. We previously showed that this tail consists of three functional regions: an unpaired EF-hand domain (PC2-EF), an oligomeric coiled coil domain, and a linker connecting them. We hypothesize that the EF-hand serves as a Ca2+-sensor/switch, and show that PC2 undergoes Ca2+-induced conformational changes by NMR, CD, and SAXS. We have solved the NMR structure of Ca2+-bound PC2-EF and have identified residues with chemical shift changes upon Ca2+-titration. PC2-EF contains a novel unpaired EF-hand fold which may have evolved from a canonical paired EF-hand found in invertebrate PC2 homologs. Human PC2-EF contains a divergent helix-loop-helix in place of a second EF-hand. Temperature dependent steady state NOE experiments and NMR linewidth measurements indicate increased molecular motion in the EF-hand consistent with a proposed role for PC2-EF as a Ca2+-sensitive regulator. Structure-based sequence conservation analysis reveals a conserved hydrophobic pocket in this region, where PC2-EF may mediate Ca2+-dependent protein interactions. Using results of our structural studies we have examined the role of the EF-hand and coiled coil on PC2 channel function in single-channel lipid bilayers. Our results suggest that the coiled coil regulates PC2 by serving as an homo-oligomerization motif, whereas the EF-hand modulates the Ca2+-dependence of PC2 channel activity. Based on our results we propose a mechanism of regulation of the Ca2+-dependence of PC2 channel activity by PC2-EF.
Measuring Myths about Domestic Violence: Development and Initial Validation of the Domestic Violence Myth Acceptance Scale

ABSTRACT Despite the important contributions of Burt's (1980) Rape Myth Acceptance Scale, no similar valid and reliable measure of domestic violence myths currently exists. This article describes the development and initial validation of the Domestic Violence Myth Acceptance Scale (DVMAS). In the first study, an initial pool of 80 items was evaluated and an 18-item instrument constructed. A second validation study indicated that the DVMAS had excellent reliability (alpha = .88) and good face and content validity as well as good indications of convergent, construct, and known groups validity. Divergent validity was only partially supported. The studies also indicated that domestic violence myths serve individual psychological functions as well as social functions related to blaming the victim, exonerating the perpetrator, and minimizing the violence.
Radical radiotherapy for T4 carcinoma of the skin of the head and neck: A multivariate analysis

Sixty-seven patients with 68 stage T4 carcinomas of the skin of the head and neck were treated with radical radiotherapy at the University of Florida between October 1964 and November 1989. Thirty-three lesions were previously untreated and 35 were recurrent. Twenty-nine lesions were squamous cell carcinomas, 37 were basal cell carcinomas, and 2 were basosquamous carcinomas. Minimum follow-up was 2 years. The 5-year local control, local control including surgical salvage, and cause-specific survival probabilities were 53%, 74%, and 75%, respectively. Local control rates with radiotherapy alone were poorer in patients with recurrent lesions (41% vs. 67%, p = .07) or bone involvement (40% vs. 62%, p = .08). Results were analyzed by multivariate methods using local control, local control with surgical salvage, and cause-specific survival as endpoints. The parameters analyzed were histology; size of primary lesion; previous treatment (previously untreated vs. recurrent); involvement of bone, nerve, or cartilage; and skeletal muscle invasion. Three important prognostic factors were identified, each predictive of poorer ultimate local control and cause-specific survival rates: (a) bone involvement (p < .01); (b) recurrent lesions (p < .01); and (c) nerve involvement (p < .02). Radiotherapy alone can control advanced carcinomas of the skin of the head and neck, although lesions that have recurred after prior treatment and those with involvement of bone or nerve are associated with a lower likelihood of cure.
Differential sensitivity of isolated rat thymocytes to glucocorticoids following concanavalin A stimulation.

Concanavalin A (Con A) rapidly stimulates leucine incorporation into trichloroacetic acid (TCA) precipitable, but not TCA soluble material in isolated rat thymocytes. This stimulation of leucine incorporation by Con A is dose dependent, time dependent, and is inhibited by the addition of cycloheximide. In non mitogen stimulated thymocytes, cortisol (10−6 M) inhibits leucine incorporation into protein by 30%, whereas in Con A stimulated cells, cortisol inhibits leucine incorporation by 50%. The cortisol effect in Con A stimulated cells is present when cortisol and Con A are added simultaneously, is diminished when cortisol is added at intervals after Con A and is dependent on the concentration of cortisol administered. The inhibitory effect of cortisol on leucine incorporation is dose and time dependent in both control and Con A treated cells. The magnitude of the cortisol effect does not differ in control and Con A stimulated thymocytes for the first 3 h of steroid exposure, after which time a significant increase in the glucocorticoid effect occurs only in the Con A stimulated cells. This increased response to cortisol occurs at a time which is coincident with the mean maximal response of these cells to Con A alone. Both progesterone and cortexolone (10−6 M) inhibit leucine incorporation in control cells only slightly. The magnitude of these effects does not change by stimulation of the thymocytes with Con A. Under the conditions of these experiments, the rate of accumulation and the levels of nuclear glucocorticoid receptors are the same in both control and Con A stimulated thymocytes. These data indicate that thymocyte responsiveness to glucocorticoid is increased following exposure to concanavalin A. This enhanced response to glucocorticoid probably occurs subsequent to nuclear accumulation of steroid receptor complexes.
Interference mitigation using spectrum sensing and dynamic frequency hopping

Wireless communications are prone to both unintentional and intentional RF interference. Such interference has significant impact on the reliability of packet transmissions. In this paper, we consider interference mitigation in frequency hopping (FH) systems. We employ cognitive radios (CRs) for proactive interference sensing in such systems. Through this proactive approach, we propose a scheme for dynamic adjustment of the FH sequence. Our protocol, called SSDFH, relies on exploiting the spectrum sensing capabilities of CRs for proactive detection of channel quality. We analyze the characteristics of the proposed SSDFH using a continuous-time Markov chain framework. Level crossing rate (LCR) analysis is used to determine the transition rates for the Markov chain, which are then used to measure the “channel stability,” a metric that reflects the freshness of sensed channel interference. The selection of different protocol parameters is studied by means of analysis. In particular, we provide a numerical procedure for determining the “optimal” total sensing time that minimizes the probability of “black holes.” We run simulations to study the performance of our proposed protocol.
Classification of masses on mammograms using support vector machine

Mammography is the most effective method for early detection of breast cancer. However, the positive predictive value for classification of malignant and benign lesion from mammographic images is not very high. Clinical studies have shown that most biopsies for cancer are very low, between 15% and 30%. It is important to increase the diagnostic accuracy by improving the positive predictive value to reduce the number of unnecessary biopsies. In this paper, a new classification method was proposed to distinguish malignant from benign masses in mammography by Support Vector Machine (SVM) method. Thirteen features were selected based on receiver operating characteristic (ROC) analysis of classification using individual feature. These features include four shape features, two gradient features and seven Laws features. With these features, SVM was used to classify the masses into two categories, benign and malignant, in which a Gaussian kernel and sequential minimal optimization learning technique are performed. The data set used in this study consists of 193 cases, in which there are 96 benign cases and 97 malignant cases. The leave-one-out evaluation of SVM classifier was taken. The results show that the positive predict value of the presented method is 81.6% with the sensitivity of 83.7% and the false-positive rate of 30.2%. It demonstrated that the SVM-based classifier is effective in mass classification.
Thermodynamic expansion of nucleation free-energy barrier and size of critical nucleus near the vapor-liquid coexistence

Nucleation free-energy barrier height and size of the critical nucleus are expanded in powers of the chemical potential difference between the supersaturated vapor (or expanded liquid) in the metastable state and the saturated vapor-liquid system in the stable equilibrium state at the same temperature. The coefficients in the expansions are expressed in terms of the thermodynamic properties at the stable equilibrium state. Comparisons with the results obtained from the density-functional calculation for nucleation of the Lennard–Jones fluid show that systematic improvement in predicting properties of the critical nucleus, either liquid droplet or vapor cavity, is achieved by adding the higher order terms in the expansions. The scaling relations proposed by McGraw and Laaksonen are found to be good approximations to the general expansion; in particular, the barrier height displacement appearing in these scaling relations is naturally given as the second order coefficient in the expansion of the barrier height.
SU-E-J-112: Evaluation of Surface Tracking System for Respiratory Sensing in 4DCT: Commissioning of GateCT

Purpose: To analyze the consistency and accuracy of the respiratory signal tracking from the GateCT™ for 4DCT scanning. Methods: This experiment involved the use of the GateCT™ system, RPM™ system, GECT scanner, QUASAR respiratory motion platform (Chest Wall Platform), and MATLAB. Both GateCT and RPM systems were used to collect data on the CT scanner, using 20 various‐range breathing patterns (12 simulated & 8 patients). Once data was acquired with both systems, MATLAB was used to analyze the possible frequency and amplitude discrepancies between input and recorded signals. Results: All recorded breathing patterns of both GateCT and RPM had a frequency percent error less than 4% from the ideal frequency despite some breathing patterns being irregular. Also, the correlation coefficients of GateCT and RPM, with respect to the input breathing pattern, had an average percent difference of 1.26% within the range of 0.24%–3.22%. GateCT accurately recorded the frequency of the input breathing pattern, but sometimes displayed an amplitude drift within its data. The amplitude drift within the recorded breathing pattern of GateCT has shown to be significant when the chest wall platform has amplitudes less than 0.42cm. When the chest wall platform has amplitude greater than 0.50cm, the amplitude drift has a change of less than 5%, rendering the amplitude drift insignificant. Conclusions: GateCT has shown its accuracy and consistency in recording the frequency of any breathing pattern, be it typical or irregular. Due to its accurate tracking, GateCT is trustworthy of tracking the breathing pattern of any patient, in result, producing high quality 4DCT images that will improve the patient's treatment plans. When a patient has breathing amplitude less than 0.42cm, RPM should be used due to GateCT displaying a significant amplitude drift. In conclusion, GateCT provides accurate data necessary for high quality 4DCT images.
Monocyte chemoattractant protein-1 is a mediator of acute excitotoxic injury in neonatal rat brain.

Abstract Monocyte chemoattractant protein-1 is a chemokine with potent monocyte activating and chemotactic effects. Monocyte chemoattractant protein-1 gene and protein expression is rapidly up-regulated in response to a variety of acute and chronic central nervous system disorders. The activation and recruitment of microglia and monocytes into areas of inflammation may play a critical role in the pathogenesis of acute brain injury. Monocyte chemoattractant protein-1 could be a pathophysiologically important mediator of the microglial and monocyte responses in the brain. Using a well-characterized model of acute excitotoxic brain injury in neonatal rats, experiments were designed to evaluate whether monocyte chemoattractant protein-1 plays a role in the progression of tissue damage. Direct co-administration of recombinant monocyte chemoattractant protein-1 with the excitotoxin N -methyl- d -aspartate exacerbated injury, both in the striatum and in the hippocampus, by 55% and 167%, respectively. Complementary experiments to determine the effect of functional inhibition of monocyte chemoattractant protein-1, using an anti-monocyte chemoattractant protein-1-neutralizing antibody, revealed that co-administration of the antibody with N -methyl- d -aspartate attenuated tissue injury in the striatum and hippocampus by 57% and 39%, respectively. Together, these data suggest that monocyte chemoattractant protein-1 is a mediator of acute excitotoxic brain injury in neonatal rats and that inflammatory mechanisms contribute significantly to the pathogenesis of acute neonatal brain injury. Whether chemokines are pathophysiologically relevant mediators of neuronal injury in human neonates remains to be determined.
Accountability, autonomy and stress: principal responses to superintendent change in a large US urban school district

This study investigates how principals in a large US urban school district responded to two different superintendents who employed contrasting leadership styles and utilised divergent organisational schemes. We originally conducted interviews with principals in 2007, when the district's superintendent asserted fierce performance demands and limited principals’ site-based discretion in favour of protecting and exerting central office power. We conducted interviews again in 2013 after a new superintendent had relaxed school test score expectations and distributed the central office's previously tight, centralised control into largely self-directing sub-regions. Our findings demonstrate that superintendent change noticeably affected how principals understood and encountered accountability, autonomy and stress. To help make sense of our findings, we employ a three-part conceptual framework drawn from the study of educational leadership. We conclude by considering implications, including the notion that unrele...