cssi/SciSciGPT-SciSciNet huggingface dataset:
MASS DIFFUSION IN NEUTRAL AND UNSTABLY STRATIFIED BOUNDARY-LAYER FLOWS

Abstract Turbulent diffusion of matter from a point source within a two-dimensional boundarylayer flow over a smooth surface, with and without surface heating, has been studied. Concentrations downstream from a simulated point source located at the floor of a wind tunnel test section were measured using ammonia as the diffusing gas. The concentration profiles for the neutral and unstable conditions are found to be similar; that is, a universal function is obtained by describing χ(x, y, z)/χmax(x, 0, 0) the relative concentration in each section as a function of the similarity lengths σ(x) and η(x). The similarity lengths are defined as χ(x, σ, 0)/χmax(x, 0,0) = 0 5 and χ(x, 0, η)/χmax(x, 0, 0) = 0.5; they are found to be approximately independent of ambient velocity over the range of 6–25 ft/s and increase markedly in magnitude with increasing instability. A method for numerically integrating point source data to obtain line source plumes is given. The synthetic line source plumes so obtained are compared with actual line source data and with line source heat diffusion data. The data for heat and mass diffusion are very similar. An attempt is made to evaluate the ratio of heat and mass diffusivities by integrating the two-dimensional diffusion equation using the approximate similarity of the concentration and velocity distributions. An approximate value of 1.8 is found for this ratio.
When is an easy task difficult and vice versa? A reply to lane☆

Abstract Lane has argued that kantowitz and Knight incorrectly predicted an interaction between primary and secondary task difficulty for the variable-allocation model of attention. It is shown that such an interaction is indeed obtained if task-performance difficulty is defined in terms of capacity and only reasonable transformations of data are permitted. This interaction holds for any set of monotonic resource operating characteristics.
Operator Models for Supervisory Control Systems

This paper presents a conceptual discussion of four human operator models that are potentially useful for supervisory control applications: the operator function model (Mitchell, 1987), the problem behavior graph (Newell and Simon, 1972), the decision ladder (Rasmussen, 1986), and goal-means network (Woods and Hollnagel, 1987). These models are characterized along the dimensions proposed by Jones and Mitchell (1987) and are further examined in-depth with the use of verbal protocols collected concurrently with the performance of a supervisory control task.
Electroluminescence of AlN

Electroluminescence in the visible region is observed when AlN is excited by either ac or dc. The emitted spectra consist of narrow bands in the 400-500 m\ensuremath{\mu} region and broad continuous bands in the 500-700 m\ensuremath{\mu} region. The broad bands vary according to the activator agents. With ac, the luminescence is in phase with the applied voltage. With dc, light is emitted in the vicinity of the cathode and decays with time. This decay can be explained by polarization. The presence of a barrier at the cathode is indicated. Impact excitation is proposed.
A ‘Boundary Layer’ Method for Obtaining an Approximate Equation for the Velocity–Time History of an Accelerating Sphere

A sphere starting from rest in a stationary fluid accelerates under the action of gravity and eventually reaches a terminal velocity. The descriptive equation for the acceleration of the sphere is a first order, non-linear, ordinary differential equation, which can be solved using a finite difference scheme. In this study, we present a method (obtained from boundary layer methods) of generating a velocity—time equation to obtain an alternative solution. The method is used to solve a specific example and the results are compared to those obtained with the numerical solution. The comparison yields a small error, and so the polynomial approximation method can be used as an alternative technique to describing the motion of an accelerating sphere.The accelerating sphere problem is usually encountered in a study of flow past immersed objects. Boundary layer methods are usually taught at the graduate level. The advantage of the method presented here is that boundary layer methods can be introduced to undergradua...
The Efficiency of Two Groups of N Machines Served by a Single Robot

Many modern manufacturing facilities use carousel conveyors for storage of work-in-progress, and automatic devices to place and retrieve items in and from the storage locations. The ‘carousel conveyor problem’ is directly related to the ‘patrolling repairman problem’ reported by others. In this paper, we extend the model to include a single robot serving two or more carousels. The approach makes use of known results for the patrolling repairman.
Independent component analysis using a genetic algorithm

The independent component analysis (ICA) problem involves finding a set of statistically independent signals from a set of measurements consisting of unknown, perhaps convolutive mixtures of those signals. This problem arises in many applications such as speech processing, communications, and biomedical signal processing. We present a method to blindly separate instantaneous mixtures of non- Gaussian signals using a genetic algorithm (GA) and higher order statistics. The GA searches for a separating matrix such that the resulting output signal are both statistically independent and strongly non-Gaussian as measured by the kurtosis. The GA uses a binary representation together with a coarse-to-fine strategy to speed convergence and avoid such bits. Using data from a simulated narrow band communications scenario, we examine the algorithm's performance as signal length and sensor noise level are varied. We compare this performance with that obtained using the ACI algorithm developed by Comon. We show that the GA is able to achieve good separation of dense signal constellations, and achieves better separation with lower mean-square estimation error than the ACI, albeit with much higher algorithmic complexity. The improvement in performance may be dramatic when the signal length is short.
Low-frequency electromagnetic field measurements near FACTS devices

Flexible AC Transmission system (FACTS) devices are installed in substations in order to enhance the operation of the electric power transmission and distribution system. As the thyristors within the FACTS device switch on and off, they inject high frequency voltages and currents into the power system. There has been limited information to date regarding the magnetic flux density (B) and electric field strength (E) in the 60 Hz to 3 kHz range resulting from this switching. The objective of the project described here was to investigate the spatial and temporal variations in B and E in this frequency range for contemporary FACTS devices. Measurements were made at three stations. Three-axis B sensors and a single axis (vertical) E sensor were moved around the station to various strategic locations. Measurement traverses were taken at a height of 1 meter in the control room, the pump room, the inverter hall and the switchyard. In general it appears that the stations considered were designed and are operating in such a manner that reference levels for magnetic flux density and electric field strength for either occupational or general public exposure identified by various standard setting agencies (IEEE, ACGIH, ICNIRP) are not exceeded.
Cytogenetic and molecular analysis in Angelman syndrome.

We report on cytogenetic and molecular analyses of 29 Angelman syndrome (AS) individuals ascertained in 1990 through the first National Angelman Syndrome Conference. High resolution GTG- and GBG-banded chromosomes were studied. Standard molecular analysis with six 15q11q13 DNA sequences was used to analyze copy number and parental origin of 15q11q13. Concordance between molecular and cytogenetic data was excellent. The combined data showed that 23 of the 27 probands (85%) on whom we had definitive results have deletions of the chromosome 15q11q13 region. Two classes of deletion were detected molecularly: most patients were deleted for the 5 more proximal probes, but in 2 cases the deletion extended distally to include in sixth probe
SU‐FF‐I‐09: Comparison of Radiation Dose Indexes For CT Scanners: Measured Verses Automated Scanner Calculations

Purpose: Modern CTscanners provide radiation dose indexes such as CTDI and DLP for every patient based upon the selected scan parameters. Our goal is to study the potential sources of errors for these automated calculations. Method and Materials: The measured and automated radiation dose indexes were compared on five different CT models from two manufacturers. Acrylic cylindrical phantoms with diameters ranging from 6 – 32 cm were utilized for the study. Measurements were made at all available kVp's and typical scan techniques in both axial and helical modes. The measured CTDI and DLP values were compared with the displayed automated values. Results: The automated displayed CTDI and DLP values are derived from system calibration using fixed size phantoms representing a typical adult head (16 cm) and adult body (32 cm). They vary with parameters such as kVp, mAs, pitch, x‐ray beam collimation and selected protocols. For typical adult head, our measured CTDI and DLP values agreed with the automated values to an average of 7.8% discrepancy. Similarly, an average of 14% discrepancy was observed for typical adult body. However, the discrepancies widened significantly for those measured on other sizes. For pediatric body scans using a 16 cm diameter phantom on table top, the measured CTDI values are more than doubled compared to the displayed automated values. Conclusion: It is important to realize that the automated radiation dose indexes by CTscanners only represent estimates based upon standardized adult body and head sizes. No considerations are given to patient age, size, weight and tissue composition. Especially, the values for pediatric scans are not represented correctly by the automated CTDIs. Future calculated radiation dose assessments needs to be incorporated with more patient factors.
Effects of a shaped pattern preference on depth avoidance by human infants in the visual cliff situation.

Stimmafy.-19 crawling infants were presented on the visual cliff. Subsequently, a preference for a smaller checked pattern was successfully established for 10 infants in a non-depth situation where both patterns were placed directly beneath the glass. Although no infancs descended to the deep side when patterned surfaces were displayed in the pretest, 5 of 10 infants who reached criterion for the shaping procedure descended to the deep side and 5 to the shallow in a posttest. Under nonpatterned conditions, a consistent preference for shallow or deep sides was not evidenced in either pretest or posttest conditions. The purpose of the present study was to assess the role of experience as it relates to avoidance behavior by human infants in the visual-cliff situation. A number of studies with other animals have assessed experiential factors. Rearing Ss over the deep side of a visual cliff has been found to reduce subsequent cliffavoidance behavior in chicks (Tallarico & Farrell, 1964; Kramer & Carr, 1968) and in rats (Kaess & Wilson, 1964; Carr & McGuigan, 1965). Rosen and Ison (1964) gave hooded rats 10 trials and varied deprivation and incentive conditions. It was found that over 10 trials, cliff avoidance declined, reinforcement changed the frequency of cliff avoidance, and the trial's effect was more apparent under low deprivation. Studies not involving prior experience with stimulus material present in the visual-cliff situation, suggest that other environmental influences affect later cliff-avoidance behavior in rats (Eichengreen, Coren, & Nachmais, 1966), in cats (Held & Hein, 1963), and in lambs (Lemmon & Patterson, 1964). In rhe human infant, the role of experience as it relates to avoidance behavior in the visual-cliff situation has received little experimental attention. As in other animals, the implication has been that the emergence of visual depth avoidance is primarily contingent upon maturation. Walk and Gibson (1961) suggesced that avoidance and apprehension of height seem to be present as soon as the infant has adequate locomotion. Discrimination of depth cues in the visualcliff situation, however, appears to occur earlier than the developlnent of locomotor abilities. Camps, Langer, and Krowitz (1970) found a significant deceleration in heart rate when 44- to 115-day-old infants were placed over the deep side, but no significant change in heart rate when infants were placed over the shallow side. Campos and Langer (1971) found the same effect among 8-wk.
A qualitative evaluation of a new community living model: medical foster home placement

Background: The Department of Veterans Affairs (VA) Medical Foster Home (MFH) program is an alternative to nursing home (NH) placement for veterans who are NH-eligible but prefer to receive care in private homes. Program expansion is ongoing; however, inefficiencies exist in targeting Veterans for enrollment. Methods : Semi-structured interviews were conducted with 35 individuals, 9 national MFH coordinators, 14 Primary Care Team Members, 2 veterans living in MFHs, 4 of their family members, 3 caregivers, and 3 family members of veterans who declined to participate in the program. Transcripts were analyzed using a general inductive approach supported by Archive for Technology, Lifeworld and Everyday language, text interpretation (ATLAS ti) V6.2. Results: Three themes were identified as key facilitators of successful MFH placement: 1) The Environment – veterans needed to have appropriate and comfortable physical space that ensured safety and was in a desirable geographic location; 2) The Match – a collaborative relationship between veterans, care providers, and the medical team providing care within the home was essential; and 3) Perceptions and Expectations about the ability for needs to be met in MFHs and challenges related to health concerns, relocation, and costs. These themes, when integrated into the Social Ecological Model, provide a theoretical framework from which to guide future research and understand policy implications. Conclusions: MFHs represent a novel alternative to NH placement. This evaluation provides an understanding of factors that lead to successful MFH placement and integrates these themes into a theoretical framework designed to assist both VA policymakers interested in expanding the program and those within the civilian community seeking to study alternatives to traditional NH care.
Evolution of particle number distribution near roadways. Part III: Traffic analysis and on-road size resolved particulate emission factors

On-road size-resolved particulate emission factors were computed using concurrently measured carbon monoxide (CO) as a freeway dilution indicator and correlating roadside particle measurements to CO measurements. The emission factors derived for the total particle number agree well with previous on-road investigations. However, this study extends this analysis to produce unique receptor-dependent, size-resolved, road and grid-level emission factor distributions. Both mileage- and fuel-based particle number and mass emission factors at road and grid levels, along with CO emission factors, are presented and the results from freeways with distinctly different percentages of heavy-duty diesel truck traffic are compared. The effects of plume processing on particle number near roadways are shown to be much more profound than on particle mass, further indicting that the adverse health effects observed near roadways are at least partially related to particle numbers.
A neutral gas phase mechanism for the reaction of methanol with dimethylphosphinic fluoride

Abstract A neutral gas phase reaction pathway for the reaction of methanol with dimethylphosphinic fluoride is presented. This reaction pathway occurs via a proton transfer from methanol to the fluorine leaving group through the phosphinyl oxygen. Gas phase ab initio level calculations at the RHF/6-31G(d), RHF/6-31G(d,p), B3LYP/6-31+G(2d), and B3LYP/6-311++G(2d,p) level of theories were used to follow the complete pathway for this reaction. A 41.2 and a 30.9 kcal/mol gas phase energy barrier was determined for both the RHF/6-31G(d,p) and B3LYP/6-311++G(2d,p) levels of theory, respectively.
A novel approach to Paget's disease diagnosis and monitoring using near-infrared absorption spectroscopy

Paget’s disease of bone affects about 1 to 3 percent of people over 40 years of age in the United States. The disease is characterized by an increase in the rate of bone remodeling due to excessive osteoclast activity; therefore patients with Paget’s disease can develop severe bone deformities. Pagetoid bones are large, fragile and prone to fractures. A hallmark of Paget’s disease of bone is a marked increase in vascularization in bones. The fingerprint determinants of vascularization are deoxyhemoglobin (Hb) and oxyhemoglobin (HbO2), which are the key chromophores in the NIR “tissue optical window” from 700nm to 1200nm. We have designed a Bone Optical Analyzer which utilizes optical spectroscopy imaging to non-invasively measure the changes of Hb and HbO2, thus enabling early diagnosis and monitoring of disease progression in these patients. Using inverse imaging algorithms, based on the diffusion equation, 2D and 3D maps of the bone’s internal structure can be reconstructed. The use of NIR light will allow for repeated studies on patients with Paget’s disease quickly, safely, inexpensively and without the risks associated with standard procedures. The model will be tested on bone tissue phantoms which mimic the scattering properties of human bone. This work will be the foundation for the future use of this device in vivo.
Propagation of pulse trains through a random medium

Applying the parabolic approximation, the equations for two-frequency symmetric and antisymmetric mutual intensity functions for waves propagating through a random medium are derived, including the multiple scattering effects. These functions are applied to derive the general formulas for the covariance functions of narrowband pulses. They are used to compute the signal intensities for pulse trains passing through an ionospheric irregularity slab.
Surgical therapy for drug-refractory ventricular tachycardia: Results with mapping-guided subendocardial resection

Surgical therapy with mapping-guided subendocardial resection was used in 30 patients with drug-refractory ventricular tachycardia. Results of preoperative, intraoperative and postoperative electrophysiologic evaluation and long-term clinical follow-up are reported. Left ventricular aneurysm was located in the inferior wall in 8 patients and in the anterior wall in 22. Left ventricular mapping was performed in 15 patients preoperatively and in all 30 patients intraoperatively. Subendocardial resection was supplemented with cryoablation in 26 patients and with laser photocoagulation in 4. Coronary bypass surgery was performed in 27 patients. The surgical mortality rate was 10%; the three deaths were due to cardiogenic shock, pneumonia and sepsis, respectively. At postoperative electrophysiologic study, ventricular tachycardia was inducible in 8 (30%) of 27 patients. Previously ineffective antiarrhythmic drugs were effective in preventing the induction of ventricular tachycardia in four of these eight patients. Two of the remaining four patients received an automatic implantable cardioverterdefibrillator; the other two were treated with amiodarone. At a mean follow-up period of 18 +/- 17 months (range 1 to 52), there has been one sudden death and one nonfatal recurrence of ventricular tachycardia in the 18 patients without inducible arrhythmias postoperatively. Among the eight patients with inducible ventricular tachycardia after subendocardial resection, there has been one nonfatal ventricular tachycardia recurrence. Thus, among the 27 patients surviving surgery, 17 (63%) were cured with surgery alone, and another 7 (26%) had their ventricular tachycardia controlled with drugs (n = 5) or the defibrillator (n = 2). Inability to completely map the tachycardia, a clinical history of cardiac arrest requiring resuscitation and the presence of myocardial infarction within 2 months predicted postoperative arrhythmia inducibility and recurrence.
A Congenital Heart Defect in Drosophila Caused by an Action-Potential Mutation

The mutation no action potential (nap) induces arrhythmia in the heartbeat of Drosophila melanogaster larvae at temperatures above 20 degrees C; heartbeat becomes normally rhythmic again after a shift back to 20 degrees C. For this phenotype, napa is almost completely recessive to the wild type, napa also reduces the temperature-sensitivity of heart rate over a wide range of temperature, for this phenotype, napa is dominant over the wild type, napa causes reversible paralysis in adults by epistatic effects on the expression of paralyrica, a gene encoding a voltage-dependent sodium channel. However, the paramutation, which induces paralysis in adults at 29 degrees C, has no effect on larval heartbeat at temperatures between 20 degrees and 37.5 degrees C. The period gene, contra earlier reports, has no effect on heartbeat.
Women's parliamentary representation: are women more highly represented in (consolidated) democracies than in non-democracies?

Although there have been many studies that address the representation of women in parliament, there are few analyses that compare the current state of gender representation between democracies and non-democracies. Focusing on Africa, Central and South America, as well as Asia and the Pacific region, this paper evaluates whether democracies have more female deputies or whether female representation increases with the maturity of democracy. While controlling for the type of electoral system, quotas, women's participation in the workforce, a state's GDP, as well as its degree of corruption and Communist regime type, this cross-national analysis reveals that the variable democracy does not affect the representation of the genders in parliament. Women's parliamentary representation also does not increase with the maturity of democracy.
Smart structure applications using neurocontrollers

This paper describes a neural network-based digital control system for a wide range of dynamic applications. Two diverse applications of the digital control of smart structural systems are discussed to illustrate the general nature of this neurocontroller. The first application is reduction of vibration in optical mirrors for large high energy laser installations. Under neurocontrol, multiple actuators and sensors reduce the `jitter' caused by cooling water flow and other vibration sources affecting the mirrors within the laser system. Accelerometers provide control parameters. The control and reduction of high intensity acoustic noise is a similar application of neurocontrollers. In this case, multiple acoustic sources are controlled to reduce the measured noise at multiple microphone locations. Both examples used the same neurocontroller with a filtered-x architecture. Minor adjustments to accommodate either the `macro'-scale dynamics of high-intensity acoustics, or the `micro'-scale dynamics of optical mirror vibrations were made as needed. The paper includes results from actual tests.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Systemic cognitive-developmental therapy: organizing structured activities to facilitate family development

Integrative models of psychotherapy provide clinicians with a number of benefits, including organized access to a variety of assessment and intervention strategies throughout the course of treatment. Such benefits allow practitioners to be flexible in therapy, to tailor treatment to the specific needs of their clients, and to service a wide range of client types. Systemic cognitive developmental therapy (SCDT) represents one such integrative marriage and family treatment model that uses a cognitive-developmental framework to design assessment procedures, create developmentally oriented treatment plans, and evaluate the effectiveness of the therapeutic process. Because SCDT draws from a variety of family counseling and therapy approaches, it can provide clinicians access to a wide range of familiar structured activities and exercises for use in treatment. In this article, the authors describe the SCDT model and illustrate how this cognitive-developmental framework can be used to organize various structured...
Microfluidic Device Architecture for Electrochemical Patterning and Detection of Multiple DNA Sequences

Electrochemical biosensors pose an attractive solution for point-of-care diagnostics because they require minimal instrumentation and they are scalable and readily integrated with microelectronics. The integration of electrochemical biosensors with microscale devices has, however, proven to be challenging due to significant incompatibilities among biomolecular stability, operation conditions of electrochemical sensors, and microfabrication techniques. Toward a solution to this problem, we have demonstrated here an electrochemical array architecture that supports the following processes in situ, within a self-enclosed microfluidic device: (a) electrode cleaning and preparation, (b) electrochemical addressing, patterning, and immobilization of sensing biomolecules at selected sensor pixels, (c) sequence-specific electrochemical detection from multiple pixels, and (d) regeneration of the sensing pixels. The architecture we have developed is general, and it should be applicable to a wide range of biosensing schemes that utilize gold-thiol self-assembled monolayer chemistry. As a proof-of-principle, we demonstrate the detection and differentiation of polymerase chain reaction (PCR) amplicons diagnostic of human (H1N1) and avian (H5N1) influenza.
Human cell lines expressing hormone regulated T7 RNA polymerase localized at distinct intranuclear sites.

Abstract Although several systems are now available for the controlled expression of eukaryotic genes transcribed by RNA polymerase II, regulated expression has been more difficult to achieve in the case of genes transcribed by RNA polymerase III. In the present study the gene for bacteriophage T7 RNA polymerase, implanted with a eukaryotic nuclear localization signal, was linked to a 5′-flanking ecdysone-responsive promoter and stably transformed human cell lines were constructed in which the ecdysone promoter-T7 RNA polymerase gene had been integrated intact, as demonstrated by a polymerase chain reaction assay. Exposure of these cells to the ecdysone analog ponasterone A resulted in the appearance of a single protein having the expected size of T7 RNA polymerase in immunoblots of cell extracts probed with an affinity purified antibody raised against the C-terminus of T7 RNA polymerase. The induced T7 RNA polymerase was exclusively localized in the nucleus of induced cells and was undetectable in uninduced cells either by immunoblotting or immunofluorescence. The induced T7 RNA polymerase was present at numerous punctate foci dispersed throughout the nucleoplasmic regions of the nucleus and was also present in the nucleoli. Both of these observed intranuclear localizations have relevance to the potential applications of this system.
Hyperspectral remote sensing of water mass properties in a river-influenced coastal region

Coastal waters represent a challenge for ocean color remote sensing because of their high degree of optical complexity and spatial heterogeneity. Ship-based underway hyperspectral observations of remote sensing reflectance provide a means for improved spatial resolution of optical properties of coastal water masses and greater degrees of freedom for analysis of spectral features attributable to dissolved and particulate constituents. Here we compare underway measurements of surface hyperspectral radiance and irradiance with measurements determined using a profiling multispectral radiometer in coastal waters of the northern Gulf of Mexico. The two measurements were generally consistent and results illustrate the utility of remote sensing reflectance as a means of tracking water mass properties in an optically complex coastal regime, the Mississippi River plume.
Interfacial properties governing ohmic contacts between gold alloys and oriented gallium arsenide crystals

Contact angles between Au-Ge and Au-Sn alloys and {111} oriented gallium arsenide crystals were determined over the temperature ranges 360 to 450° C and 280 to 400° C, respectively. Three characteristic regions of the temperature dependence of these angles were observed. At the lower temperatures, contact angles,θ, decreased sharply with increasing temperature. This region was followed by another in which the values ofθ were essentially independent ofT and finally, at the higher temperatures,θ decreased again asT increased up to the highest limit indicated above. Based on microstructural and electron microprobe analyses these observations are explained in terms of diffusional processes at the interfacial regions between the gold alloys and GaAs crystals. Furthermore, from observations of the temperature dependence of contact angles between GaAs and pure tin, it is suggested that gold plays an important role in the observed interfacial phenomena.
Voting Behavior on the United States Courts of Appeals, 1961-1964

Voting behavior of public decision-makers has been of central concern for political scientists. For example, studies of legislatures (notably of Congress) have investigated such research problems as: (1) the extent to which voting on one issue is related to voting on other issues; (2) the potency of party affiliation as an organizer of attitudes and a predictor of voting behavior; and (3) the relationship of demographic characteristics to voting behavior. These and related concerns have more recently occupied the attention of students of the judiciary whose focus has primarily been on the United States Supreme Court. State courts of last resort have also provided a testing ground primarily for problems (2) and (3). However, the United States courts of appeals, second only to the Supreme Court in judicial importance, have been largely neglected. This paper considers the above research problems with reference to the voting behavior on all eleven courts of appeals from July 1, 1961 through June 30, 1964.
An all-optical wavelength-division meshed-ring packet-switching network

Introduces an all-optical wavelength-division packet-switching meshed-ring local/metropolitan area communication network. This architecture, known as SMARTNet (scalable multi-channel adaptable ring terabit network), allows the proposed network to offer a significant increase in the throughput capacity realized by any local/metropolitan area shared-medium network. The SMARTNet architecture is ATM capable and fits naturally with, and takes best advantage of, the kinds of high speed optoelectronic and optical components that can actually be constructed. For certain meshed-ring regular physical topologies, an upper bound on the network's throughput efficiency is derived. Specific network configurations are demonstrated which achieve a throughput efficiency level which is close to 90% of this bound. Such network structures exhibit a throughput capacity level which is 80% higher than that realized by traditional (non-meshed) ring networks.
Taking “the Game” Out of The Match: A Simple Proposal

*Residency Program, Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York; yResidency Program, Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; zResidency Program, Radiation Oncology, University of Chicago Medical Center, Chicago, Illinois; xRadiation Oncology Residency and Fellowship Program, M. D. Anderson Cancer Center, Houston, Texas; jjResidency Program, Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut; {Residency Program, Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, Maryland; and Residency Program, Harvard Radiation Oncology Program, Boston, Massachusetts
Transforming Proteins of Some Feline and Avian Sarcoma Viruses Are Related Structurally and Functionally

Abstract Transformation of chicken cells by Fujinami sarcoma virus (FSV), PRC II or Y73 (three independently isolated avian sarcoma viruses that are replication-defective and lack the Rous sarcoma virus src gene) resulted in significant elevation (4–13 fold) of phosphotyrosine levels in cellular protein. The gag-related proteins encoded by these avian sarcoma viruses (ASVs) were all associated with tyrosine-specific protein kinase activity when assayed in immune complexes and were phosphorylated at both tyrosine and serine residues in vivo. Both the phosphotyrosine level in protein of FSV-infected cells and the protein kinase activity assayed in immune complexes containing the FSV protein P140 were temperature-sensitive. The presumed transforming proteins of these ASVs were compared with those of Rous sarcoma virus (RSV), Abelson murine leukemia virus and the Snyder-Theilen and Gardner-Arnstein strains of feline sarcoma virus (FeSV), which have previously been associated with tyrosine-specific protein kinase activity. FSV and PRC II proteins were shown to be structurally related to one another and to the FeSV proteins by tryptic peptide mapping and by immunological studies. No homology was observed, however, between the transforming proteins of RSV, Y73, Abelson murine leukemia virus and the FSV/PRC II/ FeSV class, suggesting there may be at least four classes of retroviruses whose transformation mechanisms involve aberrant phosphorylation of cellular protein at tyrosine residues.
A chip-scale electrical soliton modelocked oscillator

This paper introduces a chip-scale electrical soliton modelocked oscillator, which self-generates a periodic train of electrical soliton pulses. This circuit is made possible by combining a nonlinear transmission line (NLTL) with a unique amplifier that tames the instability-prone soliton dynamics in a closed-loop NLTL. This chip-scale prototype produces a pulse width of 293ps and demonstrates the feasibility for future widths close to 1ps, adding a new direction in pulse-based electronics
Variation-tolerant circuits: circuit solutions and techniques

Die-to-die and within-die variations impact the frequency and power of fabricated dies, affecting functionality, performance, and revenue. Variation-tolerant circuits and post-silicon tuning techniques are important for minimizing the impacts of these variations. This paper describes several circuit techniques that can be employed to ensure efficient circuit operation in the presence of ever-increasing variations.
Influence of season on sexual development in heifers: age at puberty as related to growth and serum concentrations of gonadotropins, prolactin, thyroxine and progesterone.

An experiment was done to test the hypothesis that seasonal changes in environment during the first and second 6 months of life influence age at puberty in heifers. Twenty-eight Angus X Holstein heifers, born in March (M) or September (S), were reared under natural conditions until 6 months of age. From 6 to 12 months of age, heifers were reared in environmental chambers programmed to simulate seasonal changes in temperature and photoperiod characteristic of spring, summer and early autumn (Sp-F chamber) or autumn, winter and early spring (F-Sp chamber). S were younger (P<0.06) at puberty than M, and Sp-F were younger (P<0.08) than F-Sp for both M and S. Mean ages at puberty were 295 for S, Sp-F; 319 for 5, F-Sp; 321 for M, Sp-F and 346 days for M, F-Sp. Average daily gain (ADG) between 6 and 9 months of age [1.03 kg/day (S) vs. 0.91 kg/day (M)1 and mean concentrations of serum luteinizing hormone (LH) between 6 7 months of age [3.45 ng/m! (5) vs. 0.47 ng/ml (M)1 were greater (P<0.01) for S than M, suggesting an association between these traits and date of birth effects on age at puberty. Differences in these traits did not seem to be involved in the chamber effect on age at puberty, since ADG from 6-9 months of age was greater (P<0.05) for F-Sp heifers and chamber did not generally affect LH concentrations. Serum concentrations of follicle-stimulating hormone (FSH) were not significantly influenced by month of birth or chamber, but concentrations tended to decrease with age. Serum concentrations
Small Animal Models of Heart Failure Development of Novel Therapies, Past and Present

Received June 23, 2008; accepted January 20, 2009. The study of heart failure requires viable animal models whereby chronic changes in myocardial structure and function can evolve and the progression of heart failure and left ventricular (LV) dysfunction can be quantified. During the past 40 years, basic and translational scientists have used small animal models to explore the pathophysiology of heart failure and to develop novel therapies that might slow the progression of this prevalent and fatal disease. The purpose of this review is to describe commonly used heart failure models in rodents and to cite examples of how these models have been used to evaluate novel therapies for the treatment of heart failure. Heart failure models were originally developed in rats because of numerous potential advantages inherent in a small animal model (see Table 1). Housing and maintenance costs for rats are much lower than for large animals, thus reducing costs and increasing the number of animals included in a given study to improve the statistical power. Moreover, more recent technological advances in echocardiography, MRI, and micromanometer conductance catheters have greatly streamlined the assessment of cardiac function in rodents, removing a significant barrier to their use in heart failure research. The development of suitable expertise to perform open-chest surgical procedures and invasive hemodynamic assessments in rats is far easier compared with that required for mice. Additionally, investigators are able to perform a greater number of postmortem histological or molecular biological analyses given the approximately 10-fold greater myocardial mass of rats compared with mice. For these reasons, the rat models detailed below have been the most widely and successfully used heart failure models in basic and translational research. View this table: Table. Commonly Used Rodent Heart Failure Models Myocardial infarctions (MIs) in rats were originally induced by the sequential administration of subcutaneous isoproterenol …
Comprehension of the Developmental Cycle of Families in the Training of Child Psychiatry Clinicians

Learning to do effective clinical work with families is a process that evolves slowly. It requires much more than the initial enthusiasm that may follow a few successfully managed and lively family interviews. Some early experiences of that kind are essential for developing a belief in the value of the modality, but the ability to hang in with difficult families over a period of time requires a considerable depth of clinical wisdom. That kind of wisdom about families accumulates slowly and builds out of a combination of substantial theoretical comprehension and wide ranging clinical experience including trial and error, success and failure.
Restrictions Limiting the Generation of DNA Double Strand Breaks during Chromosomal V(D)J Recombination

Antigen receptor loci are composed of numerous variable (V), diversity (D), and joining (J) gene segments, each flanked by recombination signal sequences (RSSs). The V(D)J recombination reaction proceeds through RSS recognition and DNA cleavage steps making it possible for multiple DNA double strand breaks (DSBs) to be introduced at a single locus. Here we use ligation-mediated PCR to analyze DNA cleavage intermediates in thymocytes from mice with targeted RSS mutations at the endogenous TCRβ locus. We show that DNA cleavage does not occur at individual RSSs but rather must be coordinated between RSS pairs flanking gene segments that ultimately form coding joins. Coordination of the DNA cleavage step occurs over great distances in the chromosome and favors intra- over interchromosomal recombination. Furthermore, through several restrictions imposed on the generation of both nonpaired and paired DNA DSBs, this requirement promotes antigen receptor gene integrity and genomic stability in developing lymphocytes undergoing V(D)J recombination.
Externalizing Behavior Problems in Young Children: Contributing Factors and Early Intervention.

Early intervention should begin as soon as relatively stable problem behavior is detected in young children. Once professionals have identified young children who are at risk for stable externalizing behavior problems, it is important that they use and/or recommend research-based interventions. Therefore, the first purpose of this article is to present research on specific child (e.g., temperament), family (e.g., family adversity), and transactional characteristics that have been documented to contribute to the manifestation of externalizing disorders in young children. School factors that may also support externalizing behavior in young children will also be presented and include negative teacher interactions and limited support for appropriate behavior. The second purpose of this manuscript is to present screening and intervention strategies that school psychologists could may use with young children who have externalizing behavior prior to or as soon as they enter the kindergarten setting. © 2002 Wiley Periodicals, Inc.
Persistence of genetic variation in recolonized Tsuga canadensis (Eastern hemlock) populations following historic forest clearance

The recovery of genetic variation in newly recolonized populations is an important concern in forest conservation genetics. We examined the potential recovery of genetic diversity and changes to genetic structure in populations of the wind-pollinated species Tsuga canadensis that naturally regenerated following the extensive 19th century regional forest clearance for agriculture in west-central Massachusetts. We genotyped 264 individuals across six microsatellite loci and compared levels and patterns of genetic variation between primary forests (forests that were logged but never cleared) and secondary forests (stands that were recolonized following agricultural abandonment). We found no significant reductions in genetic diversity in secondary forests (AR = 5.450; HS = 0.718) compared to primary forests (AR = 5.742; HS = 0.730). Moreover, the population genetic differentiation was also not significantly reduced in secondary compared to primary forests, with no significant genetic structure observed among all populations. These results suggest rapid genetic recovery of T. canadensis populations in recolonized forests compared with other late-successional temperate tree species.
Familiarity in Source Memory

Abstract Familiarity and recollection are thought to be separate processes underlying recognition memory. Event-related potentials (ERPs) dissociate these processes, with an early (approximately 300–500 ms) frontal effect relating to familiarity (the FN400) and a later (500–800 ms) parietal old/new effect relating to recollection. It has been debated whether source information for a studied item (i.e., contextual associations from when the item was previously encountered) is only accessible through recollection, or whether familiarity can contribute to successful source recognition. It has been shown that familiarity can assist in perceptual source monitoring when the source attribute is an intrinsic property of the item (e.g., an object's surface color), but few studies have examined its contribution to recognizing extrinsic source associations. Extrinsic source associations were examined in three experiments involving memory judgments for pictures of common objects. In Experiment 1, source information was spatial and results suggested that familiarity contributed to accurate source recognition: the FN400 ERP component showed a source accuracy effect, and source accuracy was above chance for items judged to only feel familiar. Source information in Experiment 2 was an extrinsic color association; source accuracy was at chance for familiar items and the FN400 did not differ between correct and incorrect source judgments. Experiment 3 replicated the results using a within-subjects manipulation of spatial vs. color source. Overall, the results suggest that familiarity's contribution to extrinsic source monitoring depends on the type of source information being remembered.
Cooperative activation of the ATR checkpoint kinase by TopBP1 and damaged DNA

TopBP1, acting in concert with DNA containing bulky base lesions, stimulates ATR kinase activity under physiologically relevant reaction conditions. Here, we analyze the roles of the three components in ATR activation: DNA, base damage and TopBP1. We show that base adducts caused by a potent carcinogen, benzo[a]pyrene diol epoxide (BPDE), constitute a strong signal for TopBP1-dependent ATR kinase activity on Chk1 and p53. We find that the C-terminus of TopBP1 binds preferentially to damaged DNA and is sufficient to mediate damaged DNA-dependent ATR activation in a manner similar to full-length TopBP1. Significantly, we find that stimulation of ATR by BPDE-damaged DNA exhibits strong dependence on the length of DNA, with essentially no stimulation with fragments of 0.2 kb and reaching maximum stimulation with 2 kb fragments. Moreover, TopBP1 shows preferential binding to longer DNA fragments and, in contrast to previous biochemical studies, TopBP1 binding is completely independent of DNA ends. We find that TopBP1 binds to circular and linear DNAs with comparable affinities and that these DNA forms elicit the same level of TopBP1-dependent ATR activation. Taken together, these findings suggest a cooperative activation mechanism for the ATR checkpoint kinase by TopBP1 and damaged DNA.
Vessel Wall Magnetic Resonance Imaging in Acute Ischemic Stroke Effects of Embolism and Mechanical Thrombectomy on the Arterial Wall

Background and Purpose—The aim of the study was to determine the effects of thromboembolism and mechanical thrombectomy on the vessel wall magnetic resonance imaging (VW-MRI) appearance of the intracranial arterial wall. Methods—This was a cross-sectional study of consecutive patients with acute intracranial arterial occlusion who underwent high-resolution contrast-enhanced VW-MRI within days of stroke presentation. For each patient, we categorized arterial wall thickening and enhancement as definite, possible, or none using contralateral arteries as a reference standard. We performed χ2 tests to compare the effects of medical therapy and mechanical thrombectomy. Results—Sixteen patients satisfied inclusion criteria. Median time from symptom onset to VW-MRI was 3 days (interquartile range, 2 days). Among 6 patients treated with mechanical thrombectomy using a stent retriever, VW-MRI demonstrated definite arterial wall thickening in 5 (83%) and possible thickening in 1 (17%); there was definite wall enhanc...