cssi/SciSciGPT-SciSciNet huggingface dataset:
Analysis of Scaling and Instability in FRP-Concrete Shear Debonding for Beam-Strengthening Applications

The debonding mode of failure, which is observed in girders strengthened using externally attached fiber-reinforced polymer (FRP) sheets, is studied in this paper. A numerical analysis of the direct-shear response of FRP attached to concrete substrate is performed to study the initiation, formation, and propagation of an interfacial crack between the two adherents. The material response of the bimaterial interface, which includes postpeak softening, is incorporated into the numerical model. The load response obtained numerically is shown to be in close agreement with that determined experimentally from direct shear tests on concrete blocks strengthened with FRP sheets. An instability in the load response is predicted close to failure and the arc-length method is used to obtain the entire load response past the displacement-limit point. The instability in the load response is shown to be a result of snapback, where both the load and the displacement decrease simultaneously. The effect of the bonded length on the stress transfer between the FRP and concrete and on the ultimate failure is also analyzed. It is shown that there is a scaling in the load capacity when the bonded length does not allow for the establishment of the full stress-transfer zone associated with interface crack growth. From the results of the numerical analysis, a fundamental understanding of interfacial crack propagation and instability at failure in concrete members strengthened using externally bonded FRP is developed. Using a simple energy based formulation; it is shown that in strengthened girders, the instability at complete debonding of FRP from concrete translates into an explosive failure associated with a sudden release of energy.
On the discovery of the diffuse interstellar bands

This contribution attempts to reconstruct the precise history of the discovery of one of astronomy's long-lasting enigmas, the so-called diffuse interstellar bands (DIBs). While systematic research into the DIBs was initiated by Merrill in 1936, the first pointers to abnormal features in the spectra of distant stars were published some 15 years earlier by Mary Lea Heger, who researched them at Lick Observatory while a student. We have examined Heger's observing notebooks from her doctoral work in 1919–1920. We have also digitized her 1919 photographic plates, and compared the spectra that she measured with modern ones. Our conclusion is that Heger was indeed the first to observe and draw attention to the two absorption features at 5780 A and 5797 A that subsequently came to be recognized as DIBs, thereby initiating a substantial field of research that now embraces several hundred such features, all of whose provenance is unsolved even to this day.
Mechanisms of intracellular fatty acid transport: role of cytoplasmic-binding proteins.

Cytosolic binding proteins are ubiquitous, yet their functions have been poorly defined. Research in multiple labs has now clarified two major transport functions for fatty acid binding proteins (FABPs), one of the most commonly studied examples of this diverse class. Most cellular fatty acids are bound to membranes. Because fatty acids are almost insoluble in water, their movement across the water between cellular membranes is very slow without FABP. FABP increases this rate by increasing the solubility of fatty acids in water. Many forms of FABP can also increase this rate by catalyzing release of the fatty acids from membranes. The first function is most valuable over longer distances (e.g., >1 μm in rat liver cells), while the second is most valuable for shorter distances. Thus, FABPs serve complementary intracellular transport functions. These conclusions may apply to other cytosolic proteins that bind poorly-soluble molecules.
An explicit integration scheme for finite-deformation plasticity in finite-element methods

Abstract A new explicit integration scheme is presented for finite-deformation (large strains and rotations) computational plasticity. The results are accurate and stable.
Abstract 5204: Downregulation of PHLLP expression contributes to hypoxia-induced resistance to chemotherapy in colon cancer cells.

Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC Hypoxia is a feature of solid tumors. Most tumors are at least partially hypoxic. This hypoxic environment plays a critical role in promoting resistance to anticancer drugs. PHLPP, a novel family of Ser/Thr protein phosphatases, functions as a tumor suppressor by negatively regulating Akt signaling in colon cancer. Here, we show that the expression of both PHLPP isoforms is negatively regulated by hypoxia in colon cancer cells. Hypoxia-induced decrease of PHLPP expression is attenuated by silencing HIF-1α but not HIF-2α, indicating that PHLPP downregulation is HIF-1α-dependent. Whereas the mRNA levels of PHLPP are not significantly altered in hypoxia, the reduction of PHLPP expression is caused by decreased protein translation downstream of mTOR and increased protein degradation. Specifically, hypoxia-induced downregulation of PHLPP is partially rescued in TSC2 or 4E-BP1 knockdown cells as the result of elevated levels of mTOR activity and protein synthesis. In addition, we show that hypoxia promotes PHLPP degradation by increasing the mRNA expression of USP46, a PHLPP-specific deubiquitinase, and resulting in upregulation of PHLPP ubiquitination. Functionally, downregulation of PHLPP plays an important role in hypoxia-induced chemoresistance in colon cancer cells. Taken together, we have identified hypoxia as a novel mechanism by which PHLPP is downregulated in colon cancer, and the expression of PHLPP may serve as a biomarker for better understand the drug resistance in cancer treatment. Citation Format: Yang-an Wen, Tianyan Gao. Downregulation of PHLLP expression contributes to hypoxia-induced resistance to chemotherapy in colon cancer cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5204. doi:10.1158/1538-7445.AM2013-5204
Circuit model representation of a continuous wave (CW) electromagnetic induction (EMI) metal detection/discrimination system

This paper addresses continuous wave (CW) electromagnetic induction (EMI) measurements of wire loops (q-coils) and low metallic (LM) content landmines. Most importantly, measurement errors are addressed. A method based on the measurement of a q-coil with an analytically calculable response is used to produce an error correction function. When this function is used to correct EMI CW measurements of other objects cross over frequency errors are reduced relative to the uncorrected case on average by a factor of 2. Insights into the sources of systematic errors are provided through the analysis of a simple equivalent circuit model of the EMI measurement system.
Collinear quantum mechanical calculations for the reaction: He + H2+ → HeH+ + H

An integral equation reaction path technique has been used to calculate, within the collinear approximation, reaction probabilities for the reaction He + H2+ → HeH+ + H over the energy range 0.95 <- E <- 1.19 eV. This reaction differs from those that have been studied previously within the collinear approximation in that a severe oscillatory behavior is exhibited in the energy dependence of the reaction probabilities.
IN SITU GROWTH STUDIES OF In AND Ga ON Si(001) USING STM

In an STM experiment, the ability to look at the same area of the surface at different stages of growth gives information on phenomena such as nucleation that would be difficult or impossible to obtain otherwise. In this paper, we illustrate the usefulness of this capability by showing in situ growth data for In and Ga on Si(001). We show that in this system, nucleation is not dominated by defects on the substrate, and that one-dimensional metal rows grow by preferential accommodation of metal atoms at the row ends.
The rationale of genetic counseling

An account is presented of the principles of assessing genetic risk as a prelude to genetic counseling. The information used may be modular, that is, based on the use of rational genetic models; empirical and derived from population studies; or particular and based on information from the pedigree. Of these, empirical data are the least satisfactory because they are the most sensitive to the effects of incidental factors. A systematic procedure for calculation of the probabilities is given and illustrated by several examples. The method incorporates data on identification of the carrier state and on age of onset when there is age-dependent penetrance.
Evolution of strategies for the collective-risk social dilemma relating to climate change

This paper describes an N-person social dilemma game created to study how climate change agreement strategies develop. The players in this game are trying to collect a target amount for a climate aid fund. Players (countries) fall into three categories: cooperators who contribute their fair share, altruists who contribute more than their fair share and defectors who contribute nothing. In all cases we would evolve a set of player strategies that collected the target sum (− 0%/+0.5%). Our results indicate defection is a preferred strategy, but trigger strategies can markedly improve contributions. Our game is designed to see what motivates countries to live up to their agreements to contribute to climate change aid funds.
Acute blood pressure elevation and ventricular fibrillation threshold during coronary occlusion and reperfusion in the dog

The effect of acute elevation of arterial blood pressure on the ventricular fibrillation threshold was examined in 19 closed chest dogs anesthetized with chloralose during 10 minutes of occlusion followed by abrupt reperfusion of the left anterior descending coronary artery. Ventricular fibrillation threshold was determined using two methods of electrical testing: sequential R/T pulsing and the train of stimuli method. Blood pressure was increased with an intravenous injection of the alpha adrenergic stimulator phenylephrine. Acute hypertension significantly diminished the enhanced vulnerability associated with coronary occlusion. After denervation of the carotid sinus and aortic arch baroreceptors, elevation of blood pressure failed to affect vulnerability during occlusion. In both intact and denervated animals, the predisposition to ventricular fibrillation after reperfusion was unchanged by the increase in blood pressure. It is suggested that with-drawal of sympathetic tone mediated by the baroreceptor reflex is the basis for the protection against ventricular fibrillation resulting from elevation of blood pressure. The failure of acute hypertension to alter vulnerability during reperfusion suggests that the predisposition to ventricular fibrillation during reperfusion is due to mechanisms other than those operating during coronary occlusion.
On artificial machine learning: some ideas in search of a theory†

In this paper an algorithm for machine learning is defined and justified heuristically and empirically. “Consistency” properties of perfect evaluation functions are derived and these are used to select the best of a family of evaluation functions, that is, that evaluation function that is most consistent. Methods peculiar to a particular game such as rote learning, looking ahead are generally eschewed; “learning” consists of finding the evaluation which is most consistent. In the game of Nim, in which the winning strategy is well-known, we show that these principles are sufficient to derive a perfect evaluation function (under appropriate conditions) and so arrive at a winning behavioral strategy. In the Mod(6) game, for which a winning strategy is also known, we use the algorithm to deduce an evaluation function and evaluate its effectiveness. Finally, in the game of Hex we match the algorithm with a random player and observe its success.
Progress in the development of a formal lexicon for the social sciences

I would like, first, to say a few words about Dick Rudner. Dick was an extraordinary person. In his intelligence and wit, his warmth, his utter decency and his outrage at immorality, he epitomized the notion of humaneness. To have been able to know him, and to work and play with him for so many years as I did, was a great stroke of good fortune. I am going to tell you of a job of dictionary construction one about which I think there are grounds for optimism as to its feasibility and utility. What is of particular interest here is that it is a project which was begun by Dick Rudner and myself in 1958, in which we were joined by Bob Barrett six years later, and on which the three of us worked, albeit rather sporadically, until Dick's death. Barrett and I expect, within the next few years, to complete this work. Dick and I met toward the end of 1956, shortly after we had both come to Michigan State University as young faculty members he in Philosophy and I in Economics. When we met we realized that we shared many intellectual attitudes and concerns. Over the course of a year or so we began to appreciate that our complementary abilities, along with these shared interests and attitudes, offered a basis for some interesting work together.
Analytical Study of the Generation and Control of Orbit Errors in the ANL 4-GeV CW Electron Microtron Design

The 4 GeV CW Electron Microtron (GEM) Design has 3 linac sections and 3 dispersive straight sections. Six 60° sector bending magnets separate the linac and dispersion straight sections. A magnetic optical system has been designed within the dispersive straight sections to contain the beam during the 36 or 37 return passes through the linacs. A major concern is the effect of small alignment or field errors on the equilibrium or desired orbit with a relatively strong focussing system. The results of an analytical study which shows the effect of small random errors on the orbit are presented. A study was also undertaken on the control of the orbit position by making error measurements in one dispersive section and making an angular adjustment with a small dipole in the preceding dispersive section. The analysis indicates that the orbit position can be adequately and easily controlled in the presence of random alignment and field errors.
Internet economy - Unique opportunity for Slovakia

Internet Economy represents a unique “Online oportunity” for Slovakia. According to the Boston Consulting Group study, that was commissioned by Google Slovakia, Slovak republic has opportunity to become above the average Internet Economy. Today, Internet Economy of the Slovak republic (shareof Internet on GDP) is estimated at 3.3%, or 2.3 bln EUR, which is approximately the level of other internet developed countries. The share of Internet of GDP in 2016 is expected to reach 4.5%. Huge potential represents export with added value (technology export), that contributes in the whole Internet Economy up to 30%. Several leading Slovak companies succeeded globally thanks to the internet: for example antivirus company ESET, that has 150 million users worldwide, Innovatrics - world leading fingerprint-recognition software used worldwide, or GPS navigation system Sygic. Slovakia has a huge potential to stimulate set-up of other technology companies, that will create jobs with higher added value, will keep Research and Development in Slovakia, and will succeed with its products globally, thanks to the internet. In order to stimulate future growth of the Slovak republic, it is important to focus on support of education in the area of IT skills and start-up/entrepreneurial mentality. Significant number of Slovak universities graduates are unemployable at present. If additional expert trainings of IT skills would be provided to these graduates, their chance so finding jobs would increase significantly. Following an example of Estonia, Slovakia should start empowering children with necessary IT skills already from early age on. Slovak republicis in need for more university graduates with IT skills. These graduates will work not only in shared-services centers, but will also continue their growth and develop new technology products and software.
Salt effects on urea hydrolysis and nitrification during leaching through laboratory soil columns

We studied the transport and transformation of urea under steady-state conditions in two soils and at three water salinities (1.0, 5.0, and 10.0 dS/m) using laboratory soil columns. A mathematical model that considers diffusion, convection, adsorption and first-order kinetic transformation of nitrogen was used to describe measured effluent concentration of the two nitrogen species. Increasing salt levels in the applied water decreased the hydrolysis of urea in the two soils studied with first-order rate coefficients decreasing from 0.015 to 0.009 h−1 in the fine sandy loam, and from 0.075 to 0.015 h−1 in a silty loam. Similarly, the nitrification rate decreased by 50% and 70% in the two soils as salinity increased. The rate coefficients measured in the leaching studies were much smaller than measured in incubation-type experiments. Calculated half-lives for urea and NH 4 + provided a method interpreting the kinetic rate coefficients as a function of the experimental conditions.
Improved Passive Water Management Design for Use in Unitized Regenerative Fuel Cells

Proton Exchange Membrane (PEM) fuel cells require effective water transport away from the cathode to ensure stable operation. Many existing water management strategies involve active methods, reducing system efficiency by introducing parasitic losses. In the present work, we report on the improved design and fabrication of a passive water management scheme involving UV-catalyzed porous polymer wicks. The design features two connected porous domains consisting of a methacrylate-based transport layer and polyvinyl alcohol storage layer.In our previous prototype, large water transport lengths (∼12 mm) prevented adequate removal of generated water. The capillary pressure drop across the two porous domains was insufficient to drive a flow rate matched to the rate of generation. Thus, the current design produces a shorter transport distance (∼3 mm) by developing a new vertical design. An independently produced SU-8 photolithographic mold is incorporated to improve the fabrication process.Copyright © 2014 by ASME
The spontaneous azaguanine-resistant mutants of diploid human fibroblasts.

The range of incidences of azaguanine-resistant colonies in cultures of fibroblasts from 16 unrelated humans was 0.4×10-6 to 19×10-6 and the mean value was 4.1×10-6. A fluctuation test showed that most or all of the mutant colonies derived from mutations that occurred during in vitro proliferation of the fibroblasts and before exposure to azaguanine. The estimated rate of spontaneous mutation was 0.45×10-6 to 1.8×10-6 per cell generation. At least ten independent mutants, comprising two general classes, were studied. Class I mutants were a minority and resembled cells from boys having the Lesch-Nyhan syndrome: they had very little HG-PRT activity, showed maximum resistance to azaguanine and could not utilize hypoxanthine for growth. At least 90% of the mutants were in Class II: their apparent HG-PRT activities ranged between normal and Lesch-Nyhan amounts, they were partially sensitive to azaguanine and they could utilize hypoxanthine. Some Class II mutants resembled cells cultured from a family having an X-chromosomal mutant gene that does not cause the Lesch-Nyhan syndrome but does confer resistance to azaguanine, although the quantity of HG-PRT activity is apparently normal and hypoxanthine can be utilized. Electrophoretic differences between the HG-PRT activities of normal and mutant strains were not detected but other qualitative alterations were observed in some mutants.
Cytochemical differentiation of the guinea pig sperm flagellum with phosphotungstic acid.

Guinea pig sperm were treated with ethanolic phosphotungstic acid (E-PTA) after glutaraldehyde fixation with and without refixation in osmium tetroxide. PTA staining differentiated the cortex from the interior of the coarse fibers, and further differentiated the cortex into two segments, one densely stained, the other pale. The internal substance of the peripheral doublets stains heavily with PTA when sperm are not fixed in osmium tetroxide, but the limiting walls around the doublets are not apparent. Outlines of the central filaments, however, are preserved by PTA. PTA-stained sperm do not show the arms on sub-filament A, irrespective of fixation procedures. Structural relationships between the coarse fibers and the peripheral doublets are also brought out by E-PTA. In addition, this cytochemical method revealed a nodule connecting the implantation and basal plates.
Pulmonary Function Monitoring During Adenosine Myocardial Perfusion Scintigraphy in Patients With Chronic Obstructive Pulmonary Disease

Objective To determine whether adenosine could be safely administered to patients with chronic obstructive pulmonary disease (COPD) for coronary vasodilatation during perfusion scintigraphy without causing bronchospasm. Material and Methods The study was divided into two phases. In the monitoring phase, patients with COPD were pretreated with an inhaled bronchodilator (albuterol) and had pulmonary function monitored during the infusion of a graduated dose of adenosine. Eligibility for entry into this phase of the study was determined on the basis of results of pulmonary function testing (PFT) during resting. Once we had shown that adenosine could be safely administered to patients with COPD, an implementation phase was begun. Entry did not require resting PFT, and patients were administered adenosine without monitoring of pulmonary function. Differences between patients with normal pulmonary function or mild COPD and those with more severe COPD were analyzed statistically. Results Of 94 patients entered into the monitoring phase, none had obvious bronchospasm. The dosage of adenosine was reduced in four patients because of a decrease in forced expiratory volume in 1 second ( FEV 1 ) of 20% in comparison with baseline (FEV 1 before administration of albuterol). The mean FEV 1 decreased slightly from 1.83 L after administration of albuterol to 1.78 L during the maximal adenosine dose. Patients with a remote history of asthma, positive result of a methacholine challenge test, or mild COPD ( FVC 1 60 to 80% of the maximal predicted value for age) did not differ significantly in their response to infusion of adenosine from those with moderate or severe COPD ( FEV 1 30 to 59% of the maximum predicted for age). Of 117 patients in the implementation phase, 2 had bronchospasm during infusion of adenosine that was quickly terminated by stopping the administration in one patient and reducing the dose of adenosine in the other. Conclusion This study shows that adenosine can be safely administered intravenously to selected patients with known or suspected COPD to produce coronary vasodilatation for myocardial perfusion imaging. Patients who are within the guidelines established for this study should be considered for adenosine coronary vasodilatation with use of bronchodilator pretreatment, a graduated dose of adenosine, and regular chest auscultation during the infusion.
Universal web access: delivering services to everyone

To deliver services to more users, developers can try to reach more diverse users (language / culture, handicapped / disabled, gender, age, etc.). By developing and sharing methods and resources to address many dimensions of diversity, developers may improve accessibility for all.
On finding non-intersecting straightline connections of grid points to the boundary

Abstract We consider the problem of determining whether it is possible to connect a given set of N points in an ( m × n ) rectangular 2D grid to the grid's boundary using N disjoint straight (horizontal or vertical) lines. If this is possible, we find such a set of lines. We provide an algorithm with either O ( m + n ) or O ( N log N ) complexity. In higher dimensions, the problem is NP-complete. We then extend our results to accommodate an additional constraint, namely forbidding connections in opposite directions that run next to one another. A solution to this problem can be used to provide a set of processor substitutions which reconfigure a fault-tolerant rectangular array of processing elements to avoid the faulty processors while retaining its important properties.
Liquid scintillators containing metallic ions

The properties of a series of liquid scintillators containg tri-n-butyl phosphate and dissolved metallic ions were investigated for possible use in counters. The findings are summarized. (C.H.)
Suicide Rates by Region of Death and Place of Birth

It has long been known that suicide rates are highest in the western states and the northern states (Lester, 1970, 1971) and that suicide rates are higher among migrants (Kramer, et al., 1972). It is of interest to inquire, then, whether those born in the western states have higher suicide rates. Kramer, et al. (1972) used the nine standard regions of the USA and for 1959-1961 calculated suicide rates for migrants from each region who were living in each region. (The mean for the 81 suicide rates [9 places of birth by 9 places of residence] was 12.88, SD 4.33.) In the present analysis, mean suicide rates were calculated for residents of each region averaged over the groups born in each of the nine regions. The means for the residents of each region were: for the Pacific 18.8 per 100,000 per year, for the Mountain 16.8, the South Atlantic 13.5, the West South Central 12.8, New England 11.3, Middle Atlantic 11.2, West North Central 10.9, East North Central 10.8, and East South Central 9.9. Similarly, the suicide rates for those born in each region were calculated by averaging their suicide rates as residents of each of the nine regions. The mean suicide rates by region of birth were for the West North Central 15.4, for the East North Central 14.7, the Middle Atlantic 14.5, the Mountain 14.1, East South Central 13.4, South Atlantic 12.4, New England 12.2, West South Central 10.9, and Pacific 8.2. The Pearson correlation over the nine regions between the suicide rates by place of residence and by place of birth was -0.64 (two-tailed p = .06). In particular, it can be seen that, though residents of the Pacific states have the highest suicide rates, those born in the Pacific states have the lowest suicide rates. It is clear from these results, then, that suicides by place of birth have a very different geographic distribution from suicides by place of residence.
Ultra-high resolution, absolute position sensors for cryostatic applications

Recent advances in new technology, optical pattern recognition encoders at NASA have resulted in high speed, reliable, compact position sensors for use in cryostatic space flight mechanisms. New encoder scale patterns and image processing algorithms combine with digital signal processors (DSP) and field programmable gate array (FPGA) logic elements to enable encoders with conversion rates in excess of 1.5 kHz (suitable for high speed servo motion control for mechanisms), linear resolutions of less than 10 nm, and angular resolutions in the single digit milli-arcseconds in relatively compact packages. Fiber optic light guides allow encoders to function in cryostats with extremely low power dissipation. Ambient test data for fiber optic configurations suitable for cryogenic environments are presented. Cryostatic test capabilities under development are discussed. Potential applications exist for NGST and other infrared and sub-millimeter missions, such as fine guidance sensing, attitude control, mirror segment position sensing, and mirror scanning.
Application of Huang‐Yang pseudopotential to a few‐body system

Huang and Yang replace a hard core of radius c by their pseudopotential (HYPP), which can be used in perturbation theory. I show that HYPP and boundary value perturbation theory give the same energy shift, to first order in c. I model a two-body potential as an oscillator potential (angular frequency ω) and a hard core. For an A-body system, the ratio of the first order energy correction to the unperturbed energy is 0.448 A3/4c a, where a = (M ω/2h)1/2.
Modified Allen Pictures to Assess Amblyopia in Young Children

To produce a test of visual acuity for young children that is more sensitive to amblyopia than current preschool vision tests, the authors surrounded four Allen pictures with "crowding" bars. This modified Allen test was evaluated by measuring acuity of amblyopic children (n = 28) and children (n = 10) and adults (n = 5) with normal eyes. Mean acuities of amblyopic eyes for the modified pictures was 0.8 octaves or nearly three logMar Snellen lines poorer than for the isolated pictures. For nonamblyopic and normal eyes modified picture acuity averaged 0.1 to 0.4 octaves poorer than isolated picture acuity. Average acuities of amblyopic eyes (n = 22) for the modified pictures agreed with line letter acuities. These results suggest that the modified picture test induces contour interaction similar to that of line letter tests, and thus, is a more sensitive test of amblyopia in the preschool child than isolated symbols.
Models capture hydrological processes in coastal environments

It is inherently difficult, if not impossible, to observe and make adequate measurement of certain types of natural processes. For instance, whether it is the formation of landscapes, such as deltas, or fine-scale processes, such as the transport of fluids and solutes, water flowing over surfaces has presented major challenges for scientists interested in studying hydrologic processes occurring at the interface of the surface and flowing water. Although researchers have relied on numerical models to simulate hydrological processes that operate along a sediment-water interface, the method has been criticized for not being verified by in situ observations. However, new research shows that numerical simulations based on fluid dynamical properties do broadly mimic hydrological processes at the sediment and flowing water interface, at least in systems where water flows over, below, or adjacent to porous sedimentary surfaces, such as in coastal marine environments.
Serum-independent modulation of hemicyst formation by dissolved oxygen in postconfluent epithelial monolayers

Hemicyst formation is considered a manifestation of either transepithelial solute and fluid movement or secretory activity in culture. This study shows that hemicyst formation in postconfluent monolayers of rhesus monkey kidney (LLC-MK2) cells is modulated by the dissolved oxygen concentration (PO2) of the culture medium. Either daily replacement of serum-free medium or displacement of the gas phase with 18% vol/vol O2 (initial medium PO2 = 125 to 135 mm Hg) enhances formation of hemicysts. Use of 30% O2 (medium PO2 approximately equal to 175 mm Hg) does not further increase the incidence, but neither 10% O2 (medium PO2 = 90 to 95 mm Hg) nor 1% O2 (medium PO2 = 35 to 50 mm Hg), the approximate range of dissolved oxygen values in blood, supports hemicyst formation unless cultures are gently rocked to disrupt diffusion gradients. Phase photomicrography of living cultures shows that the surface of a turgid hemicyst is furrowed, and cinephotomicrography reveals that the walls vibrate subtly. When hypoxic conditions (0 to 1% O2) are introduced this vibration ceases within 2 to 3 h, whereas collapse and disappearance of turgid hemicysts requires 18 to 20 h, seems virtually synchronous, and is reversible. Hemicysts form in a broad osmotic range, and increased electrolyte concentration increases the incidence. Hemicysts persist in locally dense areas when cell-free strips are etched in the postconfluent monolayer; no DNA synthesis is detected under these conditions, but two-dimensional cell spreading into the denuded area is seen along the edge of the wound. We conclude that the dissolved oxygen supply in the cellular microenvironment modulates functional expression by differentiated kidney epithelial cells in culture and that increased electrolyte concentration also enhances expression of this phenotypic marker.
A new class of split exponential propagation iterative methods of Runge–Kutta type (sEPIRK) for semilinear systems of ODEs

Abstract In this paper the framework of the exponential propagation iterative methods of Runge–Kutta type (EPIRK) is extended to construct split EPIRK (sEPIRK) integrators for semilinear systems of ODEs. The structure of the sEPIRK methods possesses the flexibility and generality that allows construction of very efficient schemes. We demonstrate how bicolored trees-based B-series can be used to derive the order conditions for the new integrators. An algorithm is developed to solve the order conditions up to order three and several new schemes with desirable properties are proposed. The numerical results illustrate the advantages offered by the new class of integrators. The experiments also address the comparative performance of split vs. non-split EPIRK methods and the question of improving efficiency by optimizing coefficients of the sEPIRK schemes. It is shown that specific schemes can be custom-built to improve computational efficiency for a particular problem.
Head actuator dynamics of an IBM 51/4-inch disk drive

The IBM 5 1/4-inch disk drive contained in the IBM 9345 DASD Module provides high track density and storage capacity, dynamic test failure rates below three parts per million, and low sensitivity to assembly variations. The design techniques used to achieve the required vibrational characteristics of the head actuator assembly are described. Dynamic stability specifications are derived from drive performance requirements and the actuator servomechanical system design. Modeshapes of the actuator are determined by encoding magnetic patterns onto a disk and using the read/write heads as position transducers in an operational drive. Structural changes in the carriage assembly that might lead to design improvements are explored with models derived using finite element analysis. Taguchi orthogonal matrix experiments are used to reduce the sensitivity of the actuator to dimensional tolerances and assembly processes. The achievement of actuator assembly design objectives is verified from production yields and statistical data obtained during dynamic tests.
Comprehensive Application of a First Principles Based Methodology for Design of Axial Compressor Configurations

Axial compressors are widely used in many aerodynamic applications. The design of an axial compressor configuration presents many challenges. It is necessary to retool the design methodologies to take advantage of the improved accuracy and physical fidelity of these advanced methods. Here, a first-principles based multi-objective technique for designing single stage compressors is described. The study accounts for stage aerodynamic characteristics and rotor-stator interactions. The proposed methodology provides a way to systematically screen through the plethora of design variables. This method has been applied to a rotor-stator stage similar to NASA Stage 35. By selecting the most influential design parameters and by optimizing the blade leading edge and trailing edge mean camber line angles, phenomena such as tip blockages, blade-to-blade shock structures and other loss mechanisms can be weakened or alleviated. It is found that these changes to the configuration can have a beneficial effect on total pressure ratio and stage adiabatic efficiency, thereby improving the performance of the axial compression system.Copyright © 2011 by ASME
Genetic animal models of malformations of cortical development and epilepsy

Malformations of cortical development constitute a variety of pathological brain abnormalities that commonly cause severe, medically-refractory epilepsy, including focal lesions, such as focal cortical dysplasia, heterotopias, and tubers of tuberous sclerosis complex, and diffuse malformations, such as lissencephaly. Although some cortical malformations result from environmental insults during cortical development in utero, genetic factors are increasingly recognized as primary pathogenic factors across the entire spectrum of malformations. Genes implicated in causing different cortical malformations are involved in a variety of physiological functions, but many are focused on regulation of cell proliferation, differentiation, and neuronal migration. Advances in molecular genetic methods have allowed the engineering of increasingly sophisticated animal models of cortical malformations and associated epilepsy. These animal models have identified some common mechanistic themes shared by a number of different cortical malformations, but also revealed the diversity and complexity of cellular and molecular mechanisms that lead to the development of the pathological lesions and resulting epileptogenesis.
Adaptive integration activity management for on demand business process collaboration

Today businesses are interacting and collaborating more often in the context of a business value chain involving a variety of partners to deliver products and services. Business to business (B2B) connectivity, Enterprise Application Integration (EAI) and general business collaboration processes are becoming more critical in operating and managing efficient enterprises. The required level of inter and intra enterprise integration is generally a large undertaking and involves substantial development and customization efforts. In this paper, we propose an adaptive integration activity management approach based on web services technologies to reduce code changes associated with business process integration in a distributed collaboration environment. Specifically, we present a concept of activity chain to capture non-deterministic process flows as well as deterministic process flows in a uniform manner. Then an Activity Ontology is introduced to capture the integration requirements that include adaptation behaviors, action properties, business rules, and access control policy references. The unique ontology representation and management of the integration activities provides a uniform way to integrate additional internal and external business applications to reduce the need for pre-defined and hard-wired integration methods and to minimize code changes to existing components in an existing business collaboration and integration (B2B/EAI) infrastructure. In addition, a Petri-Net modeling exercise of the proposed integration activity management is performed to help better understand the actual system and improve the system design beforehand.
Spectrum of causes of pancreatic calcifications.

he discovery of pancreatic calcifications has long been used in the diagnosis of pancreatic disease, and for many years imaging of the pancreas was largely limited to the radiographic identification of these calcifications. Today, our ability to image the pancreas has greatly advanced with modalities including CT, sonography, endoscopic retrograde cholangiopancreatography, and MR imaging. This improved visualization of the pancreas allows better identification of pancreatic calcifications and their underlying cause. Traditionally, pancreatic calcifications have been largely associated with chronic calcific pancreatitis from alcohol abuse. Although alcohol abuse remains the predominant cause of pancreatic calcifications, many other causes also deserve attention. Knowing what entities cause calcifications and their typical appearance can help in an accurate diagnosis. However, imaging alone cannot be trusted for a definitive diagnosis because many of these entities overlap in their appearance [1]. We report a spectrum of causes and imaging appearances related to calcification of the pancreas.
Value-based analysis of routine pathologic septal and inferior turbinate specimens.

ObjectiveTo determine the frequency and clinical relevance of unanticipated histopathologic results in routine sinonasal surgery and evaluate the necessity for histologic processing of nasal septal cartilage, bone, and inferior turbinate specimens.Study DesignCase series with chart review.SettingTertiary care academic medical center.Subjects and MethodsA retrospective review of surgical pathology reports on adult patients undergoing sinonasal surgery during a 5-year period from 2005 to 2010 was performed. All cases with the preoperative diagnosis of sinonasal neoplasia, autoimmune disease, or directed septal biopsies were excluded from review.ResultsA total of 1194 pathology reports were reviewed from 1172 individual patients. This included histopathologic evaluation of 1194 septal cartilage and bone specimens and 714 inferior turbinate specimens. None of the patients had unanticipated histopathologic findings that were clinically significant.ConclusionMany surgeons obtain histopathologic diagnoses on all...
The Effects of Surface Coating and Orienting of Whiskers on Mechanical Properties of SiC(w)/Si3N4

In order to strengthen and toughen Si3N4 ceramics by addition of SiC-whiskers, we tried the control of interfacial properties between whisker and matrix and of orientation of whiskers. For interfacial control, the effects of Al2O3, ZrO2 and carbon coating to the surface of whiskers were studied. The flexural strength and the fracture toughness of Si3N4 composite containing Al2O3-coated whiskers by decomposition of aluminum stearate, were stronger (1107MPa) and larger (10.2MPa·m1/2) than those of the composite with noncoated whiskers. TEM observation revealed that Al2O3-coated whiskers in the composite had smoother surface than non-coated whiskers and that a film-layer was formed at the interface between whisker and matrix. For orientation control, the flexural strength and the creep rupture resistance at 1250°C of Si3N4 composite, reinforced with uni-directionally oriented whiskers by the doctor-blade method, were much stronger (1180MPa) and much larger than those of monolithic Si3N4 ceramics. After creep testing, the new stacking fault and dislocation in the whiskers were observed by TEM. On the basis of these results, the mechanisms of toughening and high-temperature strengthening of SiC(w)/Si3N4 have been discussed.
Farm Commodity Payments and Imputation in the Agricultural Resource Management Survey

Item non response is a pervasive problem in survey data, and a large literature in statistics has developed to address missing data due to item non response. Government statistical agencies regularly impute for missing values in the microdata that they make available to researchers. Unfortunately, while the imputation methods typically used by government statistical agencies may be suitable for the main objectives of the agency—usually, publishing aggregated descriptive statistics—these imputations are usually unsuitable for multivariate analysis of microdata. Using USDA’s Agricultural Resource Management Survey (ARMS), we apply a new imputation method to missing 2008ARMS data on federal government farm commodity payments and off-farm household income items. We find that the choice of imputation method can have a noticeable effect on important economic indicators, even when the rate of missingness is small.
Quantitative Measurement of Routing Restoration Strategies for Multi-hop Wireless Networks

The ability to recover from failures and maintain an acceptable level of service degradation despite failures is a crucial aspect in the design of multi-hop wireless networks. This paper investigates routing restoration solutions in the event of node failures. In particular, we consider three strategies, namely global restoration, end-to-end restoration and local restoration, which can support a range of tradeoffs between the restoration latency and network throughput after restoration. To quantitatively evaluate the impact of node failures during and after routing restoration, we define two performance degradation indices, transient disruption index (TDI) and throughput degradation index (THI). We formulate the optimal routing restoration schemes under these three strategies as linear programming problems and implement their solutions in the ns-2 simulator. Extensive performance evaluations are performed to study the impact of node failures in multi-hop wireless network under these three routing restoration strategies. To the best of our knowledge, this is the first work that quantitatively compares the optimal route restoration strategies in multi-hop wireless networks in terms of performance degradation during and after restoration.
The who and where of HIV in rural Malawi: exploring the effects of person and place on individual HIV status.

Few spatial studies explore relationships between people and place in sub-Saharan Africa or in the context of human immunodeficiency virus (HIV). This paper uses individual-level demographic and behavioral data linked to area-level, spatially referenced socio-economic and access data to examine how the relationships between area- and individual-level risks and individual HIV status vary in rural Malawi. The political economy of health framework guides interpretation. Geographically weighted regression models show significant, local-level variation indicating that area-level factors drive patterns of HIV above individual-level contributions. In distinct locations, women who live further from health clinics, major roads, and major cities are less likely to be infected. For men, HIV status is strongly associated with migration patterns in specific areas. Local-level, gender-specific approaches to HIV prevention are necessary in high risk areas.
Hippocampal and Entorhinal Cortex High-Frequency Oscillations (100-500 Hz) in Human Epileptic Brain and in Kainic Acid-Treated Rats with Chronic Seizures

Summary: Purpose: Properties of oscillations with frequencies >100 Hz were studied in kainic acid (KA)-treated rats and compared with those recorded in normal and kindled rats as well as in patients with epilepsy to determine differences associated with epilepsy. Methods: Prolonged in vivo wideband recordings of electrical activity were made in hippocampus and entorhinal cortex (EC) of (a) normal rats, (b) kindled rats, (c) rats having chronic recurrent spontaneous seizures after intrahippocampal KA injections, and (d) patients with epilepsy undergoing depth electrode evaluation in preparation for surgical treatment. Results: Intermittent oscillatory activity ranging from 100 to 200 Hz in frequency and 50–150 ms in duration was recorded in CA1 and EC of all three animal groups, and in epileptic human hippocampus and EC. This activity had the same characteristics in all groups, resembled previously observed “ripples” described by Buzsaki et al., and appeared to represent field potentials of inhibitory postsynaptic potentials (IPSPs) on principal cells. Unexpectedly, higher frequency intermittent oscillatory activity ranging from 200 to 500 Hz and 10–100 ms in duration was encountered only in KA-treated rats and patients with epilepsy. These oscillations, termed fast ripples (FRs), were found only adjacent to the epileptogenic lesion in hippocampus, EC, and dentate gyrus, and appeared to represent field potential population spikes. Their local origin was indicated by correspondence with the negative phase of burst discharges of putative pyramidal cells. Conclusions: The persistence of normal-appearing ripples in epileptic brain support the view that inhibitory processes are preserved. FRs appear to be field potentials reflecting hypersynchronous bursting of excitatory neurons and provide an opportunity to study the role of this pathophysiologic phenomenon in epilepsy and seizure initiation. Furthermore, if FR activity is unique to brain areas capable of generating spontaneous seizures, its identification could be a powerful functional indicator of the epileptic region in patients evaluated for surgical treatment.