cssi/SciSciGPT-SciSciNet huggingface dataset:
Direct adaptive control using an adaptive reference model

Direct model reference adaptive control is considered when the plant-model matching conditions are violated due to large changes in the plant or incorrect knowledge of the plant's mathematical structure. Because of the mismatch, the plant can no longer track the original reference model, but may be able to track a modified reference model that still provides satisfactory performance. The proposed approach uses a time-varying ‘adaptive’ reference model that reflects the achievable performance of the changed plant. The approach consists of direct adaptation of state feedback gains for state tracking and simultaneous estimation of the plant-model mismatch. The reference model adapts to the changed plant, and is redesigned if the estimated plant-model mismatch exceeds a bound determined via robust stability and/or performance criteria. The resulting controller offers asymptotic state tracking in the presence of plant-model mismatch as well as matched parameter deviations.
A transistor automatic gain control system for audio frequencies

Automatic gain control (AGC) circuits are useful in obtaining relatively constant output levels where the input signal may vary over a wide range. Several articles have been written covering methods of controlling transistor gain in intermediate radio-frequency circuits.1,2 The usual method employed is to change one of the transistor parameters by the application of an external signal. The two basic methods of gain control indicated are: 1. Emitter current (Ie) control. 2. Collector voltage (Vc) control.
Search for states of ^4He using ^2H(d, d) and ^2H(d, p)^3H

The reactions ^2H(d,d)^2H and ^2H(d,p)^3H have been studied for bombarding energies between 3 MeV and 11 MeV. This range of energy corresponds to the region in the compound nucleus ^4He between excitation energies of 25.3 and 29.3 MeV. The yield curves obtained are smoothly varying, and there is no indication of a resonance with an appreciable deuteron partial width.
Effect of mulches on bacterial populations and enzyme activity in soil and vegetable yields

Mulches in five combinations of clear plastic, black plastic, and undecomposed leaves covered by or on top of black or clear plastic film to modify soil temperature, were used to study the enzyme activity of the soil and numbers of bacteria able to produce degradative enzymes. Yield of pepper and broccoli planted through the mulches was measured.
Ozone profiles over a suburban neighborhood

Abstract The development of ozone (O3) air quality models and the measurement of O3 dry deposition over built-up areas requires assumptions concerning the vertical distribution of O3. However, few [O3] profiles have been measured over urban and suburban areas. A 150 m thick layer of air over a suburban neighborhood in Lafayette, Indiana, U.S.A. was profiled for potential temperature, moisture mixing ratio, and oxidant concentrations during 38 soundings made between mid-day and early evening in late summer and early fall 1994. The residential neighborhood had 17% of the area covered by trees, with a mean vegetation canopy height of 9 m. Although some [O3] and oxidant concentration ([oxidant]) profiles showed a monotonic decrease or increase in concentration with height, many profiles (63%) exhibited a distinct local maximum in the profile. The local [oxidant] maxima were typically observed near the top of a relatively stable layer of air, and occurred more frequently when the local surface winds were from the agricultural rural regions to the north of the neighborhood and the air had resided within the Lafayette–Indianapolis region since the prior day. The magnitude of the local [oxidant] maximum was directly related to the 155 m [oxidant] during the mid-day and early-afternoon profiles. The presence of local maxima in many of the [O3] profiles indicate that one cannot safely assume that [O3] profiles monotonically decrease with decreasing height above all suburban areas. As a result, the estimation of O3 fluxes should always include profile measurements to assure the representativeness of the calculated flux at the measurement height to surface deposition. Correlations between measures of local traffic activity, above-canopy air temperatures, the magnitude of local [O3] maxima, and [O3] above the canopy indicate that a change in the dominant processes producing the maxima appeared to occur around the time of plant senescence.
Dosimetric advantages of enhanced dynamic wedge in small field irradiation for the treatment of macular degeneration.

Abstract Exudative macular degeneration is a process that affects the central retina and is the chief cause of blindness in people over 55 years old. Radiation appears to improve or stabilize visual acuity in some of these patients, although definitive clinical studies are ongoing. The delivery of radiation in patients with macular degeneration is unique and challenging because of the location of the surrounding structures, such as the lens and the opposite retina. The “standard” treatment technique has been an anterior oblique beam 20° above lateral to limit dose to these structures. In preference to the undesirable hot spot caused by this single-beam technique, we have employed a superior and inferior oblique pair utilizing the Enhanced Dynamic Wedge (EDW). Couch rotation was used to establish the desired treatment angles. The anterior half of the fields were blocked with the asymmetric jaw (AJ). Studies were performed to determine the value of these methods in reducing lens dose. Although the peripheral dose measurements at D max using a 60° metal wedge for ≥10 cm square fields were higher than for an open field or the EDW, for the small retinal fields there was no lens-dose reduction attributable to the EDW. However, the steep wedge angles achievable with the EDW were useful for optimizing the dose distribution for the most desirable field angles. As expected, the independent collimator was more effective in reducing transmitted dose to the lens than a typical Cerrobend block. Measurements required to predict dose in and out of the field are discussed along with the dosimeters employed in evaluating small fields (less than 5 cm square) with the EDW. The technical challenges of positioning, immobilization, treatment planning and treatment delivery are presented.
Selective Quantitation of Organic Sulfur with the Precursor Scan Method of Neutralization–Reionization Mass Spectrometry

Quantitation of organosulfur compounds in a hydrocarbon matrix was studied by the precursor scan method of neutralization–reionization mass spectrometry. The CHS+ ion was used as a marker selectively to detect and quantify sulfur compounds dissolved in a synthetic hydrocarbon mixture. Precursor ion abundances showed a linear dependence on the organosulfur content in the 1–100% concentration range. Detection limits of 0.5% were achieved, which were limited by the instrument sensitivity. Isobaric interferences of 13C isotopomers from hydrocarbons were negligible. Small interferences from oxygen- and nitrogen-containing additives are discussed. Several neutralization gases were examined to minimize interferences and to maximize the ion abundances. © 1997 by John Wiley & Sons, Ltd.
Interplanetary shock triggering of substorms: WIND and Polar

Abstract WIND solar wind data and POLAR UV imaging data are used to study magnetospheric responses to interplanetary shocks. It is found that the solar wind preconditions determine the different auroral responses. A ∼ 1.5 hr “precondition” (upstream of the interplanetary shocks) gives good empirical results. If the upstream IMF B z is strongly southward preceding interplanetary shocks, a substorm expansion phase results (44% of all events). If the IMF B z is ∼ 0, pseudobreakups occur. If B z is northward, there is no obvious resultant nightside geomagnetic activity.
Diabetes, hypophysectomy, or thyroidectomy reduces nuclear L-triiodothyronine-binding capacity of rat lung.

L-T3 (T3) receptors of the lungs of rats were found to be under hormonal control. The apparent binding capacity of T3 receptors of lungs of diabetic, hypophysectomized, and thyroidectomized rats were 0.224 ± 0.009, 0.195 ± 0.007, and 0.102 ± 0.008 pmol/mg DNA, as compared to 0.0321 ± 0.014 pmol/mg DNA for normal animals. The binding affinities for T3 in normal, diabetic, hypophysectomized, and thyroidectomized rats were 256 ± 3.24, 270 ± 3.81, 249 ± 4.03, and 260 ± 8.2 pM, respectively. The magnitude of the maximum binding capacity in these cases was apparently not due to the loss of either T3 receptors or DNA during the incubation. Serum T3 and T4 concentrations in normal rats were 120.0 ± 7.2 ng/dl and 5.9 ± 0.5 μg/dl, respectively. Diabetes, hypophysectomy, and thyroidectomy lowered these values to 79 ± 5.4, 60 ± 5.8, and 30 ± 1.6 ng/dl for T3 and 3.5 ± 0.3, 2.7 ± 0.4, and 1.9 ± 0.2 μg/dl for T4, respectively.
3D Simulations of Type-I Migration in Nearly Laminar Disks

We report results from 3D hydrodynamic disk simulations with an embedded planet. We examine the planet’s migration dependence on the disk viscosity. We find that the Type I migration can be slowed down significantly in low viscosity disks. The density feedback effect that was studied in 2D simulations still exists in 3D disks and causes the slowing down of Type I. Future work will address further the quantitative differences between 3D and 2D in slowing down the migration.
Experimental and theoretical investigation of correlated fine structure branching ratios arising from state-selected predissociation of BrO (A2Π3/2)

We present results for the v′-dependent predissociation dynamics of the BrO (A2Π3/2) state using velocity map ion imaging. Correlated fine structure branching ratios, Br(2PJ) + O(3PJ), have been measured for v′ = 5–16 states. The experimental branching ratios are non-statistical and strongly dependent on the initial vibronic state. The current measurements represent an extensive dataset containing rich information about the predissociation dynamics of this system and should provide a stringent test for modern theory. New high level ab initio excited state potentials are presented and have been optimized using experimental v′-dependent predissociation lifetimes and calculated coupling constants. Comparisons between the experimental branching ratios and the predictions based on diabatic and adiabatic limiting models are presented. We find that the adiabatic model is most consistent with the observed trends in the correlated branching ratios, in contrast to previous studies on the related ClO system.
Coal’s medium-run future under atmospheric greenhouse gas stabilization

We assess the future of coal under alternative climate stabilization regimes, investigating how the quantity and location of future coal production, trade and use depends upon five factors: the supply-side constraint of resource depletion, diversification and deepening of international trade, economic growth, trends in energy intensity, and the availability of coal-fired carbon-free electric generation technology (IGCC-CCS). Using the Phoenix computable general equilibrium model of the world economy, we find that coal is sensitive to demand-side assumptions about economic growth and energy-saving structural or technological change. In a 550 ppm stabilization emission tax scenario, the gobal coal industry initially declines sharply and then rebounds, in 2050 reaching roughly the same size as it is today—but only if IGCC-CCS is available by 2020. Under alternative stabilization regimes, IGCC-CCS penetration is a key influence on production and imports in major coal regions, where it interacts with extraction costs driven by the rate of depletion relative to trade partners.
Hepatic Enzymes of Tyrosine Metabolism in Tyrosinemia II

A middle-aged adult male with a mild form of tyrosinemia II (Richner-Hanhart syndrome) is described. Treatment with a low-tyrosine diet caused a fall in plasma tyrosine and clearing of the hyperkeratosis of the soles. Liver biopsy of this patient revealed low but measurable levels of cytoplasmic tyrosine aminotransferase and elevated levels of the mitochondrial tyrosine-metabolizing enzyme aspartate aminotransferase. It is hypothesized that these enzymes have been induced in sufficient amounts to account for the mild clinical course.
Recent Nucleon Decay Results from Super-Kamiokande

Recent experimental limits on the search for proton decay are presented. Data from Super-Kamiokande, a water Cherenkov detector with a fiducial volume of 22,500 tons of ultra pure water, are used in the analysis. Analyses from SK-I (40% photomultiplier coverage) plus SK-II (20% photomultiplier coverage) are reported with results from p → e + π 0 , p → μ + π 0 , and p → ν ¯ K + .
Isospin structure of low-lying Ti states

Abstract The 3 1 − state of 46 Ti exhibits unusual γ -decay properties, with E1 decay to the 2 2 + state being highly preferred. A theoretical investigation of the isospin structure of the first two 2 + states in 44, 46, 48 Ti provides a qualitative explanation of this observation.
Raman-active phonons in aluminum, gallium, and iron garnets*

The Raman-active phonons (3A1g + 8Eg + 14T2g) in eight different aluminum, gallium, and iron garnet crystals have been investigated. The energies and symmetries of phonons in YbAlG, YbGaG, LuAlG, and LuGaG, as well as DyIG, ErIg, YbIG, and YIG, have been determined. The aluminum and gallium garnets were measured in transmission, by use of an argon laser (5145 and 4880 A). The iron garnets were measured both in reflection, using an argon laser, and in transmission, using a Nd:YAG laser (1.064 μm). Owing to the linear magnetic birefringence of the iron garnets, the identification of phonon symmetries through polarization selection rules was not possible for our transmission data. An external magnetic field sufficient to align the magnetic domains of the iron garnets in the (110) plane at 80 K was applied both for the reflection and transmission measurements.
The purification of rat and sheep liver dihydropteridine reductases by affinity chromatography on methotrexate-sepharose

Abstract An efficient procedure employing affinity chromatography has been developed for the isolation of sheep and rat liver dihydropteridine reductases. The affinity matrix is synthesized by the carbodiimide-promoted condensation of methotrexate (MTX) and 1,6-diaminohexane to give 1-aminohexyl-6-amido-MTX, which is subsequently coupled to cyanogen bromide-activated Sepharose. The purification sequence requires (i) chromatography of a dilute acetic acid extract of diced liver on DEAE-cellulose, (ii) two successive passages of the product from the previous step through the affinity matrix, and (iii) filtration through Sephadex G-200. The products, recovered in overall 30% yields, exhibit average specific activities of 47.5 and 63 μmol of NADH oxidized/mg/min and show single bands of mobility 0.35 and 0.19 for the sheep and rat liver sources, respectively. SDS-polyacrylamide electrophoresis before and after titration with dimethyl suberimidate indicates that the enzymes are dimeric with molecular weights of 52,000 (sheep) and 51,000 (rat). Both enzymes show a preference for NADH over NADPH as cofactor. However, differences in the extinction coefficient at 280 nm, the isoelectric point, and NADH binding constants suggest that significant variations in physical characteristics exist between the two proteins.
An Electromagnetic Near-Field Sensor for Simultaneous Electric and Magnetic-Field Measurements

This paper describes the theory of a single sensor to perform simultaneous electric and magnetic near-field measurements. The theory indicates that it is possible to measure the magnetic-loop and electricdipole currents using a loop antenna terminated with identical loads at two diametrically opposite points. The theory also indicates that it is possible to choose an ideal load impedance for achieving equal electric and magnetic-field responses of the loop. Preliminary experiments have been performed using a plane-wave field to verify these results.
On time delays in lead salt semiconductor diode lasers

Recently reported value of minority carrier lifetimes and time delays in lead salt diode lasers appear anomalous [A. Qadeer et al.: Appl. Phys. A33, 181–182 (1984)]. Two laser diodes, fabricated by the same technique (Hot Wall Epoxy) and of identical chemical constituents (PbSnTe and PbSnSe) failed to provide experimental evidence supporting these recently reported values, even when operated close to, but above the respective values of laser threshold current.
The black family and social class.

Book reviewed in this article: Blacks often are stereotyped as a homogeneous population exhibiting a common way of life. Nine black families of varying income levels were studied to determine similarities and differences in life style. Middle-class blacks were found to be affluent conformists, working-class blacks respectable marginals who achieve upward mobility by their wits, and lower-class blacks exhibited a lack of commitment arising out of fears of trusting in an untrustworthy society. Black and white families were seen to share a common value system but adapt to the society differently because of racial discrimination and social class distinctions.
Sarcomatous transformation in a cellular angiofibroma: a case report

Cellular angiofibroma is a rare benign mesenchymal tumour of middle-aged adults. This tumour is usually located in the vulvovaginal or inguinoscrotal region. This report describes the case of a patient with a 3.5 cm subcutaneous mass, 2 cm below the left anterior superior iliac spine. Grossly, the mass had tan-white cut surface with a 1.5 cm tan-yellow, whorled, well-delineated nodule. Histologically, the tumour was composed primarily of cytologically bland spindle cells set in a collagenous stroma, with multiple dilated vessels. Other areas showed an abrupt transition to hypercellular sarcomatous elements, including pleomorphic cells with high mitotic activity. The tumour cells were diffusely positive for vimentin and factor XIIIa, and weakly positive for CD34. The patient did not develop any recurrences or metastases, and expired 3 years later of metastatic poorly differentiated carcinoma of unknown origin. This is believed to be the first reported case of sarcomatous transformation in a cellular angiofibroma.
Narrow-beam x-ray tests of CCD edge response.

The physical boundaries of a fully-depleted CCD can lead to distorted field lines and non-uniform response. We study this response with a beam of X-rays constrained to a width of less than one pixel (15 $\upmu$ m), and a system to map the CCD response as a function of transverse position.
Isolation of a polydisperse high-molecular-weight glycogen from rat liver☆

Abstract A new method is described for the isolation of glycogen from rat liver using centrifugation, gentle heating, and gel chromatography. The prepared polysaccharide was judged by both sucrose density gradient centrifugation and the absorbance spectrum of an I2-glycogen complex to be highly branched, polydisperse, and of an unusually high molecular weight upon comparison to other glycogens. Using adult fasted rats, this glycogen was shown to be better than high-molecular-weight cold water-ethanol extracted glycogen for the binding of glycogen metabolizing enzymes. Further, the addition of 0.5% ( w v ) of the glycogen to a crude liver extract from newborn rats facilitated the isolation of an almost 700-fold purified glycogen synthase with 40% recovery. It is suggested that this glycogen could also be used to study the role of enzyme binding in the regulation of carbohydrate metabolism.
Material modelling and failure modes in metal plasticity

Abstract This paper is concerned with introducing some aspects of material modelling for metal plasticity which have particular relevance to the description of localized deformation and failure modes. These aspects of metal constitutive behavior are discussed in more detail in various papers in this volume dealing with material modelling and localized plastic flow and failure. Stress and strain state, and path dependence of strain hardening is discussed from the standpoints of existing phenomenological constitutive theories, experiment, and physically based constitutive models. In addition, a brief discussion is given of the experimental phenomenology of localized deformation as observed over a range of physical size scales. As summarized, the observations indicate that localized for deformation is, in many cases, caused by micro-fractures that occur during plastic deformation but can also be the natural outcome of large strain deformation process in homogeneous, damage free strain hardening materials. Some effects of strain rate sensitivity are discussed as regards path dependent stress-strain response and localized plastic flow.
Laser doppler velocimetry measurements of velocity fields and transitions in viscoelastic fluids

Abstract A new, automated, two-color laser Doppler velocimetry apparatus is described which has been constructed especially for mapping flow fields for viscoelastic fluids. This system is capable of measuring both slow, secondary flows and time-dependent motions that are characteristic of viscoelastic flow in complex geometries. Application of this apparatus to flow between eccentric cylinders and through an axisymmetric sudden contraction for a Newtonian fluid and for polyisobutylene (PIB) and polyacrylamide (PAC) solutions is described. In both geometries excellent agreement is found between calculations and experiments for Newtonian fluids, as expected. The Newtonian recirculation region which is present for flow between cylinders with large eccentricity disappears for the PAC solution and shrinks with increasing De for the PIB solution. These changes are attributed to the substantial shear thinning of the PAC solution and the slight shear thinning of the PIB mixture under the conditions studied. New flow transitions were discovered in the sudden contraction flow of the polyisobutylene solution. At a critical value of Deborah number De 1 ≈ 0.80 the flow changed from a steady, two-dimensional motion, nearly identical with the Newtonian result, to a time-periodic flow with a tangential velocity component that fluctuated about zero. Multiple, time-periodic motions and flow hysteresis were found for De 1 De De 2 ≈ 1.20. At De 2 the flow suddenly reverts to a two-dimensional, time-independent motion. A vortex emanating from the lip of the contraction was observed for De > De 2 .
Combining trace sampling with single pass methods for efficient cache simulation

The design of the memory hierarchy is crucial to the performance of high performance computer systems. The incorporation of multiple levels of caches into the memory hierarchy is known to increase the performance of high end machines, but the development of architectural prototypes of various memory hierarchy designs is costly and time consuming. In this paper, we will describe a single pass method used in combination with trace sampling techniques to produce a fast and accurate approach for simulating multiple sizes of caches simultaneously.
Effects of fish nests on pattern and zonation of submersed macrophytes in a softwater lake

Abstract Nests of centrarchid fishes maintain patches of diaspore-propagated submersed aquatic plants (principally Elatine minima (Nutt.) and Isoetes braunii Dur.) between 0.9 and 2.4 m depth in a softwater oligotrophic lake. Nests are cleared of vegetation in May–June, and abandoned by fish in June. By August, many nests are colonized by diaspore-propagated species that do not spread vegetatively on horizontal stems. About 75% of the nests are reoccupied by fish the following May, and some new nests are formed. Nests not re-occupied by fish are colonized by rhizomatous plants of 4 species that have not been observed to flower or set seed in the lake. Rhizomatous plants reach frequencies near 100% by 14 months after abandonment. Pattern analyses show that patch sizes of diaspore-propagated species correspond to the size of fish nests. Conventional explanations of macrophyte zonation based on depth, exposure, and competition are insufficient in this lake; effects of disturbance must be considered as well.
Single Photon Detectors for Ultra Low Voltage Time-Resolved Emission Measurements

Using time-resolved emission to measure electrical signals inside very-large-scale integration complementary metal-oxide-semiconductor circuits in a non-invasive fashion is a very powerful technique. However, node scaling and the related supply voltage reduction have created significant challenges. In this paper, we investigate the limits of established and prototype single photon detectors for future low voltage applications. In particular the performance of a state of the art InGaAs single photon avalanche photodiode and a superconducting single photon detector are reported and compared for low voltage applications using test vehicles fabricated in IBM 65 nm silicon on insulator technologies.
Leaving Neverland A Randomized Trial for Coarctation Shows Pediatric Interventional Cardiology Is Growing Up

Coarctation of the aorta is commonly considered a relatively simple form of congenital heart disease. On the basis of early knowledge of the significant mortality associated with unrepaired coarctation, surgical therapy was first developed and performed in the mid-1940s.1–3 In many ways, the seemingly simple problem of pediatric coarctation has lent itself to a myriad of treatment strategies, including transcatheter intervention. The community of pediatric cardiologists and cardiac surgeons, faced with these broad options, has failed to reach consensus about optimal management. Even 12 years after publishing the early results of a randomized trial comparing angioplasty with surgery in the treatment of children with coarctation, Cowley and colleagues continue to acknowledge the ongoing and active controversy surrounding the topic.4,5 See p 3453 In this issue of Circulation , Cowley and colleagues present the long-term results of this trial, with a relatively small number of patients and incomplete follow-up. Using a composite outcome that comprises reinterventions …
Factoring Differences for Iterative Change Management

An approach for factoring source-code differences is presented. A single large difference between two versions of a program is decomposed into factors (i.e., smaller changes). The application of all the factors is equivalent to the application of the single large difference. The factors are obtained by user-defined criteria. They include changes that are limited to a specific syntactic construct or ones that occur throughout a file. The factors can be applied individually or in combination to generate intermediate forms of the large change. This directly supports iterative software change management by decomposing large changes into smaller factors. The approach uses srcDiff, an XML representation of multiple versions of a source-code file and their differences. XML transformations are used to factor a change according to an XPath expression. The approach is applied to changes made to a large opensource system. The results indicate the approach is flexible and efficient, and can be integrated with common differencing tools.
Conducting Effective Focus Groups in the Context of Diversity: Theoretical Underpinnings and Practical Implications

Demographic trends reveal that the socially and culturally relevant diversity of patients, caregivers, and managers in health care organizations will continue to increase. In addition, social attitudes are moving from a goal of assimilation or homogenization to one of differentiation and maintenance of subgroup identity. These shifts in demographics and social attitudes require the associated development of theory and practice guidelines for focus groups conducted in the context of diversity. Diversity has a profound impact on factors ranging from study design to the selection and training of facilitators and the analysis of results. Racial identity development theory, models of communication style differences, ethnographic studies of cultural archetypes or ethnic markers, and the author's experiences in facilitating focus groups that explore the sensitive topic of race/ethnicity provide insights for researchers and practitioners who want to ensure that focus groups conducted in the context of diversity produce valid results.
Handheld micromanipulation with vision-based virtual fixtures

Precise movement during micromanipulation becomes difficult in submillimeter workspaces, largely due to the destabilizing influence of tremor. Robotic aid combined with filtering techniques that suppress tremor frequency bands increases performance; however, if knowledge of the operator's goals is available, virtual fixtures have been shown to greatly improve micromanipulator precision. In this paper, we derive a control law for position-based virtual fixtures within the framework of an active handheld micromanipulator, where the fixtures are generated in real-time from microscope video. Additionally, we develop motion scaling behavior centered on virtual fixtures as a simple and direct extension to our formulation. We demonstrate that hard and soft (motion-scaled) virtual fixtures outperform state-of-the-art tremor cancellation performance on a set of artificial but medically relevant tasks: holding, move-and-hold, curve tracing, and volume restriction.
Robustification of estimators by Winsorizing on ellipsoids

Abstract For many of the more complex models in statistical genetics and measurement error analysis (such as, e.g., variance component models) robust methods are obviously needed, but as yet hardly used. This is partly due to the fact that the parameters of such models often have an indispensable subject-matter interpretation which potential robust substitutes might lack. In this paper some tools are presented to robustify given procedures rather than to construct new ones. The main technical devices are generalized moments and a homotopy argument; they appear to be of interest for any approach to robustness.
On the Stabilization of Ion Sputtered Surfaces

The classical theory of ion beam sputtering predicts the instability of a flat surface to uniform ion irradiation at any incidence angle. We relax the assumption of the classical theory that the average surface erosion rate is determined by a Gaussian response function representing the effect of the collision cascade, and consider the surface dynamics for other physically motivated response functions. We show that although instability of flat surfaces at any beam angle results from all Gaussian and a wide class of non-Gaussian erosive response functions, there exist classes of modifications to the response that can have a dramatic effect. In contrast to the classical theory, these types of response render the flat surface linearly stable, while imperceptibly modifying the predicted sputter yield vs incidence angle. We discuss the possibility that such corrections underlie recent reports of a “window of stability” of ion-bombarded surfaces at a range of beam angles for certain ion and surface types, and describe some characteristic aspects of pattern evolution near the transition from unstable to stable dynamics. We point out that careful analysis of the transition regime may provide valuable tests for the consistency of any theory of pattern formation on ion sputtered surfaces.
Information sources in library and information science doctoral research

A citation analysis of 61 library science and information science dissertations revealed some interesting publication patterns. About 80% of the citations are to single authors, and as in analyses of periodical literature, males are cited more than females overall (about 61% to 39%). In dissertations related to school or public libraries, the male/female distribution is less disparate; for studies in academic or special libraries two thirds of the authors are male, and male authorship is 75% when only information science dissertations are analyzed. Journal articles are cited more than books, book chapters, proceedings, theses, and other formats with College & Research Libraries and Journal of the American Society for Information Science used most. Library and information science is impacted by several other disciplines, primarily education, computer science, health/medicine, psychology, communications, and business. Authors cited in dissertations represent a somewhat less parochial list in terms of citing U.S. publications than authors cited in studies analyzing journal citations; over half of all works cited were published within the last 10 years.
Lemierre's syndrome, reemergence of a forgotten disease: a case report

Lemierre's syndrome is a rare disorder of young adults caused by the anaerobic bacterium, Fusobacterium necrophorum and occasionally by other Fusobacterium species (F. nucleatum, F. mortiferum and F. varium etc). The condition is characterized by a primary oropharyngeal infection with evidence of septic thrombophlebitis, exhibited by positive blood cultures, clinical or radiographic evidence of internal jugular vein thrombosis, and at least one metastatic focus. The incidence of Lemierre's syndrome is reported to be nearly one in a million. In the pre-antibiotic era, Lemierre's syndrome followed a fulminant, often fatal course. During the 1960s and 1970s, the syndrome was rarely reported when penicillin was commonly prescribed to treat oropharyngeal infections. Today, antibiotic-resistant organisms are a major concern, thus causing more prudent prescribing of antibiotics. We present a case report of a 27-year-old man with worsening pharyngitis, which illustrates that subsequent reemergence of this often forgotten disease may become more common in clinical setting.
Change in the elasticity of a random heteropolymer chain induced by freezing

We consider a simple model of a random heteropolymer chain that is known to undergo the freezing transition. We investigate the change in the elastic properties of the chain upon freezing. The elastic constants are evaluated and it is shown that they acquire a non-trivial contribution in the frozen phase.
De Roover on Business, Banking, and Economic Thought

The untimely death of Raymond de Roover in March 1972 removed one of the major figures from the field of medieval economic history. Now there has appeared a collection of eleven of de Roover's articles, one of them not previously published, to remind us of the magisterial quality of their author's contributions to our knowledge of medieval business and banking techniques and the milieu in which the medieval man of business operated.
Research Using Synchrotron Radiation at the National Synchrotron Light Source

The National Synchrotron Light Source (NSLS) is now becoming operational with synchrotron radiation experiments beginning on the 700 NeV VUV electron storage ring. Commissioning of the 2.5 GeV x-ray storage ring has also begun with the experimental program expected to begin in 1983. The current status of the experimental program and instrumentation, and the plans for future developments, will be discussed. Although some early results have been obtained on VUV beam lines no attempt will be made in this paper to describe them. Instead, an overview of the beam line characteristics will be given, with an indication of those already operational. In the oral presentation some initial experimental results will be discussed.
Factors Affecting the Presence of Nesting Burrowing Owls in an Agricultural Landscape

Abstract We examined factors that influenced the presence of nesting Western Burrowing Owls (Athene cunicularia hypugaea) along roadsides and irrigation water-conveyance systems within an intensive agricultural area in Imperial Valley, southeastern California. We conducted walking line-transect surveys along randomly selected 1-km segments of roads to examine the types of roadside attributes and agricultural crops that were associated with the presence of nesting Burrowing Owls. Occupied burrows were more likely to be located along roadsides adjacent to fields where crops were present, but we found no obvious association with any particular type of crop. However, the type (concrete delivery canal or earthen drainage ditch), number, and location of irrigation trenches between the road and the agricultural field affected the likelihood of detecting owl nests. We failed to detect any effect of trench depth or whether the road was paved on the presence of Burrowing Owls. We found more occupied burrows on road...
Epicardial Phrenic Nerve Displacement During Catheter Ablation of Atrial and Ventricular Arrhythmias Procedural Experience and Outcomes

Background— Arrhythmia origin in close proximity to the phrenic nerve (PN) can hinder successful catheter ablation. We describe our approach with epicardial PN displacement in such instances. Methods and Results— PN displacement via percutaneous pericardial access was attempted in 13 patients (age 49±16 years, 9 females) with either atrial tachycardia (6 patients) or atrial fibrillation triggered from a superior vena cava focus (1 patient) adjacent to the right PN or epicardial ventricular tachycardia origin adjacent to the left PN (6 patients). An epicardially placed steerable sheath/4 mm-catheter combination (5 patients) or a vascular or an esophageal balloon (8 patients) was ultimately successful. Balloon placement was often difficult requiring manipulation via a steerable sheath. In 2 ventricular tachycardia cases, absence of PN capture was achieved only once the balloon was directly over the ablation catheter. In 3 atrial tachycardia patients, PN displacement was not possible with a balloon; however, a steerable sheath/catheter combination was ultimately successful. PN displacement allowed acute abolishment of all targeted arrhythmias. No PN injury occurred acutely or in follow up. Two patients developed acute complications (pleuro-pericardial fistula 1 and pericardial bleeding 1). Survival free of target arrhythmia was achieved in all atrial tachycardia patients; however, a nontargeted ventricular tachycardia recurred in 1 patient at a median of 13 months’ follow up. Conclusions— Arrhythmias originating in close proximity to the PN can be targeted successfully with PN displacement with an epicardially placed steerable sheath/catheter combination, or balloon, but this strategy can be difficult to implement. Better tools for phrenic nerve protection are desirable.
Social Support and Nocturnal Blood Pressure Dipping: A Systematic Review

Background Attenuated nocturnal blood pressure (BP) dipping is a better predictor of cardiovascular disease (CVD) morbidity and mortality than resting BP measurements. Studies have reported associations between social support, variously defined, and BP dipping. Methods A systematic review of the literature was conducted to investigate associations of functional and structural social support with nocturnal BP dipping assessed over a minimum of 24 hours. Results A total of 297 articles were identified. Of these, 11 met criteria for inclusion; all studies were cross-sectional in design and included adult participants only (mean age = 19 to 72 years). Evidence was most consistent for an association between functional support and BP dipping, such that 5 of 7 studies reported statistically (or marginally) significant positive associations with BP dipping. Statistically significant functional support-BP dipping associations were moderate (standardized effect size (d) = 0.41) to large (d = 2.01) in magnitude. Studies examining structural support were fewer and relatively less consistent; however, preliminary evidence was observed for associations of marital status and social contact frequency with BP dipping. Statistically significant structural support findings were medium (d = 0.53) to large (d = 1.13) in magnitude. Conclusions Overall, findings suggest a link between higher levels of functional support and greater nocturnal BP dipping; preliminary evidence was also observed for the protective effects of marriage and social contact frequency. Nonetheless, the relatively small number of studies conducted to date and the heterogeneity of findings across meaningful subgroups suggest that additional research is needed to substantiate these conclusions.
A self-recombining bacterial artificial chromosome and its application for analysis of herpesvirus pathogenesis

A self-recombining bacterial artificial chromosome (BAC) containing the 142-kb pseudorabies virus genome was constructed such that the viral genome is rapidly excised from the BAC vector backbone on delivery into mammalian cells. The recombination is mediated by loxP sites in the plasmid and Cre recombinase encoded within the BAC vector. A synthetic intron inserted in the middle of the cre ORF completely inhibits recombination in Escherichia coli, but is spliced out after delivery of the plasmid into mammalian cells. Recombination is efficient, and pure virus lacking the BAC vector backbone is immediately isolated from transfected mammalian cells without the need of serial passage or plaque purification.
Osteochondritis Dissecans of the Knee.

First described as a named entity by Konig in a classic German text in 1887[1][1], osteochondritis dissecans has more recently been defined by a research study group of high-volume osteochondritis dissecans surgeons, musculoskeletal radiologists, physical therapists, and researchers[2][2] as “a
Development of the Visual System in Hypopigmented Mutants

The ganglion cells of most vertebrate retinas are distributed nonuniformly across the retina. Three major retinal specializations occur within the ganglion cell layer: the visual streak, the area or fovea centralis, and the nasotemporal division. Understanding the mechanisms that influence the development of these specializations has become a central theme in visual and developmental neuroscience (see also Chapters 6, 9, and 10 in this volume).
Discretization of Continuous Action Spaces in Extensive-Form Games

Extensive-form games are a powerful tool for modeling a large range of multiagent scenarios. However, most solution algorithms require discrete, finite games. In contrast, many real-world domains require modeling with continuous action spaces. This is usually handled by heuristically discretizing the continuous action space without solution quality bounds. In this paper we address this issue. Leveraging recent results on abstraction solution quality, we develop the first framework for providing bounds on solution quality for discretization of continuous action spaces in extensive-form games. For games where the error is Lipschitz-continuous in the distance of a continuous point to its nearest discrete point, we show that a uniform discretization of the space is optimal. When the error is monotonically increasing in distance to nearest discrete point, we develop an integer program for finding the optimal discretization when the error is described by piecewise linear functions. This result can further be used to approximate optimal solutions to general monotonic error functions. Finally we discuss how our theory applies to several practical problems for which no solution quality bounds could be derived before.
Homeostasis alteration within small intestinal mucosa after acute enteral refeeding in total parenteral nutrition mouse model

Feeding strategies to care for patients who transition from enteral nutrient deprivation while on total parenteral nutrition (TPN) to enteral feedings generally proceed to full enteral nutrition once the gastrointestinal tract recovers; however, an increasing body of literature suggests that a subgroup of patients may actually develop an increased incidence of adverse events, including death. To examine this further, we studied the effects of acute refeeding in a mouse model of TPN. Interestingly, refeeding led to some beneficial effects, including prevention in the decline in intestinal epithelial cell (IEC) proliferation. However, refeeding led to a significant increase in mucosal expression of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), as well as an upregulation in Toll-like receptor 4 (TLR-4). Refeeding also failed to prevent TPN-associated increases in IEC apoptosis, loss of epithelial barrier function, and failure of the leucine-rich repeat-containing G protein-coupled receptor 5-positive stem cell expression. Transitioning from TPN to enteral feedings led to a partial restoration of the small bowel microbial population. In conclusion, while acute refeeding led to some restoration of normal gastrointestinal physiology, enteral refeeding led to a significant increase in mucosal inflammatory markers and may suggest alternative strategies to enteral refeeding should be considered.
Pathways for the Recognition of the Intestinal Microbiota

The specific role of most of these newly discovered DC subsets in antigen sampling and presentation is unknown and it remains therefore unclear whether they work synergistically, as alternatives or have distinct functions in the recognition of the intestinal microbiota. The focus of effort in this field will be to understand how these diverse DC subsets cooperate in regulating the complex homeostasis and host defense in the different intestinal immune compartments. The intestinal lamina propria contains a DC network that serves as a newly discovered gateway for the uptake and transport of the intestinal microbiota. Specialized vesicular structures at the end of transepithelial dendrites serve as 'luminal sensors' for the mucosal immune system. Characterization of the surface components of these luminal sensors may aid in developing strategies to prevent bacterial and viral pathogen entry. We propose that the lamina propria and M cell-dependent antigen sampling systems are associated with specific DC subsets. The discovery of functionally defined subsets of dendritic cells associated with distinct mechanisms responsible for the uptake of antigens across the intestinal barrier opens the path for strategies for targeting them specifically in the development of vaccines or treatment approaches for inflammatory bowel diseases. For these exciting possibilities to progress into practical applications, it needs to be established whether distinct DCs subsets are associated with multiple pathways or if their function is linked to specific innate or adaptive immune responses. Defining DC function in the intestine will be pivotal in finally progressing our understanding on how the mucosal immune system makes the distinction between commensal microbiota, pathogens and self antigens.
Efficient Algorithm to Construct Perfect Secret Sharing Scheme for a Given Access Structure

The threshold scheme, the monotone circuit construction, and the vector space construction are some of the well-known secret sharing schemes in cryptography. The threshold and monotone circuit secret sharing schemes are fairly easy to construct for any given access structure Γ. The construction of a secret sharing scheme realizing a given access structure Γ with Vector Space Construction requires the existence of a function φ from a set of participants into a vector space, that is, φ: P → (Zp)d. This function φ must satisfy certain conditions in order to recover the secret key. There is no known algorithm to construct such a function φ in general. Constructions are mainly done by trial and error. In this paper, we develop polynomial algorithm to construct such φ function(s) for given access structures. Using the φ function, we also give an algorithm to construct secret sharing scheme for the access structures.
What You See Depends Upon How You Look: A Photographic Journey of Transformative Learning

In this article, the authors explore the camera lens as a metaphor for seeing the world in different ways. Their own stories and backgrounds with photography illustrate how they have come to make these connections. The authors present six increasingly abstract approaches to photography, as a way of demonstrating ‘‘what you see depends upon how you look.’’ They relate this to a holistic approach to transformative learning.