cssi/SciSciGPT-SciSciNet huggingface dataset:
MR demonstration of edema adjacent to a liver metastasis: Pathologic correlation

MichaelJ.Lee,1SanjaySaini,1Carolyn C.Compton,2 andRonaldA.Malt3T2-weighted MRimagesoflivermetastases occasionallyshowaperilesionalincreaseinsignalintensityintheformofaring(halo)orwedge(pyramid).ThisperilesionalincreaseinsignalintensitymakestumorsappearlargeronT2-weightedimagesthanonTi-weightedimages(Fig.1)[1](CohenEKetal.andSimeoneJFetal.,presentedattheannualmeetingoftheSocietyforMagnetic Resonance ImaginginMedicine,1989).Inaradiologic-pathologic study,Cohenetal.(CohenEKetal.,SMRMmeeting, 1989)foundviabletumorcellssurrounding thelesionseenonMRimagesandascribedtheringlikeareaofhighsignalintensitytoperilesionalinvasionby
Metabolic profiles of rats of different ages.

Urine samples from 6- to 31-month-old male Fischer F344 rats were analyzed using a high performance liquid chromatograph and a unique computer-based data analysis and quality control system in order to discover substances that could be used as markers in the aging process. Metabolic profiles of the organic acids from these urines yielded 42 peaks whose areas could be measured reliably. Of the 42 peaks, 10 were found by analysis of variance to vary significantly (p < 0.05) with age. Rats from the four ages could also be distinguished using a multivariate statistic (discriminant analysis).
Stem cell biology and its therapeutic applications in the setting of spinal cord injury

✓ The development of an acute traumatic spinal cord injury (SCI) inevitably leads to a complex cascade of ischemia and inflammation that results in significant scar tissue formation. The development of such scar tissue provides a severe impediment to neural regeneration and healing with restoration of function. A multimodal approach to treatment is required because SCIs occur with differing levels of severity and over different lengths of time. To achieve significant breakthroughs in outcomes, such approaches must combine both neuroprotective and neuroregenerative treatments. Novel techniques modulating endogenous stem cells demonstrate great promise in promoting neuroregeneration and restoring function.
Stopping, Straggling, and Blooming of Directed Energetic Electrons in Hydrogenic and Arbitrary-Z Plasmas

From fundamental principles, the interaction of directed energetic electrons with hydrogenic and arbitrary-Z plasmas is analytically modeled. The effects of stopping, straggling, and beam blooming, a consequence of scattering and energy loss, are rigorously treated from a unified approach. Enhanced energy deposition occurs in the latter portion of the penetration and is inextricably linked to straggling and blooming. These effects, which have a strong Z dependence, will be important in evaluating the requirements of fast ignition and tolerable levels of electron preheat.
Towards a human–robot symbiotic system

Abstract Partnership between a person and a robot could be simplified if the robot were intelligent enough to understand human intentions and perform accordingly. During the last decade, we have been developing such an intelligent robot called ISAC. Originally, ISAC was designed to assist the physically disabled, but gradually became a test bed for more robust human–robot teaming (see http://eecs.vanderbilt.edu/CIS/ ). In this paper, we will describe a framework for human–robot interaction, a multi-agent based robot control architecture, and short- and long-term memory structures for the robot brain. Two applications will illustrate how ISAC interacts with the human.
Inference on a future reliability parameter with the weibull process model

An inferential procedure is presented which provides confidence intervals for a future reliability parameter when reliability growth testing is only partially completed. Hypothesis tests based on this method are uniformly most powerful unbiased. These results are applicable if (1) the system failure rate can be modeled as the intensity function of a Weibull process and (2) efforts to improve reliability are assumed to continue at a steady rate throughout the intervening period of testing. The usefulness of this methodology is illustrated by evaluating the risk of not reaching some future reliability milestone. If such risk is unacceptably high, program management may have time to identify problem areas and take corrective action before testing has ended. As a consequence, a more reliable system may be developed without incurring overruns in the scheduling or cost of the development program.
A high-gain 60GHz power amplifier with 20dBm output power in 90nm CMOS

In wireless communications, high demand for superb video and audio quality increases the required transfer data rate. The unlicensed 7GHz bandwidth at V-band in North America has been drawing a lot of attention by companies and research institutions. Research topics done using CMOS fabrication, which appears to be a more appealing process due to its high level of integration, have been demonstrated to be a viable semiconductor for gigabit wireless at 60GHz [1]. According to the Federal Communications Commission (FCC) regulations, the maximum radiation power for 60GHz systems can reach up to 40dBm [2]. However, due to device limitations such as low maximum operating frequencies and low breakdown voltage, very few power amplifier (PA) designs using CMOS processes with high output power have been reported. To date, medium- to high-power amplifiers in this frequency range are normally implemented using III–V semiconductor fabrication processes.
Conversion of Millimeter-Wave Images Into Visible Displays

A new method is suggested, in which millimeter- or submillimeter-wave images are converted to visible displays. This technique can be applied to either coherent or incoherent radiation, giving the same power response per unit area for either case.The proposed device depends upon conductivity modulating a germanium panel by means of light or an electron beam in selected areas, and thereby controlling the transmission of millimeter-wave energy through the semiconductor medium. Laboratory tests are reported in which displays have been obtained from several configurations of point sources of millimeter-wave radiation.
Direct process thermal line broadening in Tm : YAG

Abstract In celebrating the seminal paper by McCumber and Sturge on thermal line broadening by one- and two-phonon processes, I briefly revisit the ruby line width question and then investigate the thermal broadening of the 12604.3 cm −1 line of Tm : YAG using optical free induction decay and spectral hole burning. This transition has recently been used in demonstrations of high-density time/frequency domain storage and optical signal processing where thermally induced dephasing is an important issue limiting performance.
Regulation of the use of human tissues and body fluids as research materials—Current modifications

Abstract The National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research (Commission) has made several recommendations for changes in federal regulations for the protection of human research subjects. Some of these changes will have important and felicitous consequences for biochemical pharmacologists who use human tissues and body fluids as research materials. For most—but not all—proposals to use such materials for research purposes, review at a convened meeting of an Institutional Review Board (IRB) will no longer be required. Similarly, requirements to use consent forms will be curtailed substantially; in some cases it will not even be necessary to negotiate informed consent. The recommendations of the Commission for these policy changes are grounded in recent clarifications of the following concepts: (1) the meaning of risk; (2) the purpose of informed consent; (3) the purpose of consent forms; and (4) the purpose of IRB review.
Anatomy and three-dimensional reconstructions of the brain of a bottlenose dolphin (Tursiops truncatus) from magnetic resonance images

Cetacean (dolphin, whale, and porpoise) brains are among the least studied mammalian brains because of the formidable challenge of collecting and histologically preparing such relatively rare and large specimens. Magnetic resonance imaging offers a means of observing the internal structure of the brain when traditional histological procedures are not practical. Furthermore, internal structures can be analyzed in their precise anatomic positions, which is difficult to accomplish after the spatial distortions often accompanying histological processing. In this study, images of the brain of an adult bottlenose dolphin, Tursiops truncatus, were scanned in the coronal plane at 148 antero-posterior levels. From these scans a computer-generated three-dimensional model was constructed using the programs VoxelView and VoxelMath (Vital Images, Inc.). This model, wherein details of internal and external morphology are represented in three-dimensional space, was then resectioned in orthogonal planes to produce corresponding series of virtual sections in the horizontal and sagittal planes. Sections in all three planes display the sizes and positions of major neuroanatomical features such as the arrangement of cortical lobes and subcortical structures such as the inferior and superior colliculi, and demonstrate the utility of MRI for neuroanatomical investigations of dolphin brains.
THEMIS high‐resolution digital terrain: Topographic and thermophysical mapping of Gusev Crater, Mars

[1] We discuss a new technique to generate high-resolution digital terrain models (DTMs) and to quantitatively derive and map slope-corrected thermophysical properties such as albedo, thermal inertia, and surface temperatures. This investigation is a continuation of work started by Kirk et al. (2005), who empirically deconvolved Thermal Emission Imaging System (THEMIS) visible and thermal infrared data of this area, isolating topographic information that produced an accurate DTM. Surface temperatures change as a function of many variables such as slope, albedo, thermal inertia, time, season, and atmospheric opacity. We constrain each of these variables to construct a DTM and maps of slope-corrected albedo, slope- and albedo-corrected thermal inertia, and surface temperatures across the scene for any time of day or year and at any atmospheric opacity. DTMs greatly facilitate analyses of the Martian surface, and the MOLA global data set is not finely scaled enough (128 pixels per degree, ∼0.5 km per pixel near the equator) to be combined with newer data sets (e.g., High Resolution Imaging Science Experiment, Context Camera, and Compact Reconnaissance Imaging Spectrometer for Mars at ∼0.25, ∼6, and ∼20 m per pixel, respectively), so new techniques to derive high-resolution DTMs are always being explored. This paper discusses our technique of combining a set of THEMIS visible and thermal infrared observations such that albedo and thermal inertia variations within the scene are eliminated and only topographic variations remain. This enables us to produce a high-resolution DTM via photoclinometry techniques that are largely free of albedo-induced errors. With this DTM, THEMIS observations, and a subsurface thermal diffusion model, we generate slope-corrected maps of albedo, thermal inertia, and surface temperatures. In addition to greater accuracy, these products allow thermophysical properties to be directly compared with topography.
Infants' use of baby sign to extract unfamiliar words from the speech stream

The ability to extract words from fluent speech is crucial for language learning. Infants use environmental information to aid in this process. Baby sign is a popular trend that may aid an infant in segmenting the speech stream and extracting words. A study designed to test the effects of baby sign to aid infants in extracting words from the speech stream was conducted. Six-month-old infants were shown videos of passages where either the speaker's face, hands (sign only), or both (face and signs) were visible. A head-turn preference procedure was used to test infants' ability to identify familiarised nonsense words versus control nonsense words. The resulting data are the first to demonstrate that prior exposure to baby sign can aid an infant in extracting unfamiliar words from fluent speech and six-month-old infants can use a speaker's face as a cue to extract words from speech.
Substrate Specificity of the Intracellular Proteinase from a Slow Acid Producing Mutant of Streptococcus lactis

Abstract Substrate specificity of the enzyme of the slow acid producing mutant of Streptococcus lactis No. 3 was examined using the performic acid oxidized beta-chain of insulin as substrate. The action of the enzyme on insulin resulted in the liberation of seven amino acids. Phenylalanine was released early followed by leucine, histidine, tyrosine, valine, alanine, and lysine. Sites of hydrolysis accounting for the release of the seven amino acid residues were determined. The peptide bonds involving the leucyl or phenylalanyl residues were hydrolyzed most rapidly. Specificity of the intracellular proteinase of the mutant differed significantly from that reported for the parent intracellular proteinase.
The effect of solidification microstructure on the corrosion behavior of a columnar aluminum-copper alloy

The morphological and kinetic nature of corrosion of directionally solidified aluminum-4.5 wt pct copper alloy in the as-cast, solutionized and solutionized-and-aged conditions in air-saturated aqueous 3.5 wt pct NaCl solution were evaluated. In the solutionized and solutionized-and-aged conditions the intergranular attack and pitting are similar to those occurring in solutionized wrought alloys; the extent of attack at long times increases with increasing severity of solidification rate. The as-cast alloy exhibits a cored dendritic structure with significant formation of interdendritic nonequilibrium eutectic. Extensive inter dendritic corrosion of the α-phase containing more than 3.2 wt pct copper is seen; α containing less than 3.2 wt pct copper and the θ-Al2Cu phase are cathodic. Corrosion of the as-cast alloy is parabolic with time and increases with increasing severity of solidification rate in proportion to the amount of nonequilibrium second phase.
Bioceramics. Is there a difference

Bioceramics of aluminum oxide and calcium phosphate have a wide range of applications in orthopedic surgery. Each type of bioceramic is substantially different from the other, and variations exist within each type depending on the source and intended application. The physical, mechanical, chemical, and biologic properties are specific to each bioceramic. Significantly different tissue responses have been demonstrated among the various aluminum oxide, hydroxylapatite, and tricalcium phosphate bioceramics. Since the prospects for expanded clinical applications are excellent, the clinical community should become better acquainted with these types of biomaterials.
Ovarian cancer: the neglected diagnosis.

OBJECTIVE To investigate presenting signs and symptoms of ovarian cancer and stage of tumor in a community cohort of women with the diagnosis of ovarian cancer. PATIENTS AND METHODS We reviewed retrospectively the medical records of all women who sought primary and specialty care in Olmsted County, Minnesota, between January 1, 1985, and December 31, 1997, to evaluate presenting symptoms, time from first symptom to diagnosis of ovarian cancer, and stage of tumor at diagnosis. RESULTS Of 107 women with a diagnosis of ovarian cancer, the most commonly documented presenting symptom was crampy abdominal pain. Urinary symptoms and abdominal pain were the most commonly documented presenting symptom in patients with stage I and II ovarian cancers, whereas abdominal pain and increased abdominal girth were the most commonly documented symptoms in patients with stage III and IV cancer. Approximately 15% of tumors (n=15) were found during routine evaluations or during a procedure for another problem. Less than 25% of presenting symptoms (n=24 women) related directly to the pelvis or were more traditional gynecologic symptoms. Delays in women seeking medical care, health care system issues, competing medical conditions, physicians' failure to follow up, and women not returning for follow-up were associated with longer time to diagnosis. CONCLUSION Both stage I and II cancer are associated with symptoms, but few symptoms are directly related to the reproductive pelvic organs or unique to ovarian cancer. A longer interval from first sign or symptom to diagnosis of ovarian cancer is associated with both patient and health care system factors.
Torah, language and philosophy: A Jewish critique

Modern philosophy's fascination with language for the last century, its obsession may illustrate the axiom that we love to talk about what we desire and we desire what we don't have. From the perspective of traditional Judaism, philosophic obsession with language reflects the modern philosopher's dislocation from those speech communities in which, alone, language has meaning. Natural speech communities, meaning those whose origins are either unknown or referred to an indefinite past, are characterized by inherent semiotic norms:1 rules for transforming elements of the natural world into meaningful signs (morphology), for determining relations among those signs (syntax), for determining relations between signs and intended objects (semantics), and for determining relations between signs and the actual behavior which they recommend (what the American philosopher Charles Peirce calls pragmatics).2 For the traditional Jew, these norms are collected in what is called Torah: God's speech to Israel and the literary and behavioral history of Israel's attempts to interpret what that speech means. For this Jew, dislocation from the speech community of Israel would imply dislocation from Torah, and, thereby, from the possibility of meaningful speech and controlled behavior. Jewish philosophy is the attempt to find means of reintegrating dislocated persons into appropriate speech communities: in particular of reintegrating Jews into the speech community of Israel. In the philosophic terms introduced by Peirce, Jewish philosophy's task would be to reintroduce the dislocated to those pragmatic norms through which language discloses its full meaning. This is, to be sure, to work against the tendencies of modern philosophers to reduce pragmatic meaning to semantic meaning, to identify the inherent vagueness of natural languages with error or imprecision, or to declare, in other words, the impotence of their own natural speech communities.3 For the modern philosopher, deference to pragmatic norms is suspect; general epistemological uncertainty is the norm rather than the exception. In the face of this philosophic adversity, Jewish philosophers tend to present their case apologetically, trying to describe Torah in terms set by critical or semanticist philosophy. On the following pages, I offer an alternative description: of what modern philosophy looks like in terms set by Torah. Without apology, the Jewish phi-
Glucose oxidation in hyperplastic lymphoid tissue

Summary Lymph nodes regional to injection sites of complete Freund's adjuvant show a tenfold increase in mass in 10 days. There is no alteration in the optimal activities of 5 enzymes representing varying pathways of glucose degradation in homogenates of lymph nodes taken during this growth phase. Studies of radioactive glucose conversion to CO2showed no evidence of increased utilization of the hexosemonophosphate shunt during the growth phase.
Evidence that protein synthesized in a heterologous cell-free system is not functional

Abstract Recent reports have described synthesis of proteins by Escherichia coli ribosomes in a cell-free system when ribosomal or “messenger” ribonucleic acid (RNA) is supplied ( Nirenberg and Matthei, 1961 ; Ofengand and Haselkorn, 1962). It has been claimed that the genetic code for protein synthesis carried by the “messenger” RNA is universal and, when supplied with this information, a ribosomal system can synthesize any protein. The criterion for protein synthesis in these experiments was incorporation of labeled amino acids into the acid-precipitated proteins. We have planned the following experiments to determine if a functional protein could be synthesized in such a system, and if this could be accomplished in a heterologous system. Ribosomal RNA from E . coli cells induced to form β-galactosidase was used in E . coli (homologous) and Pseudomonas pyocyaneus (heterologous) cell-free systems. The results are reported in this paper.
A minimalist approach to bias estimation for passive sensor measurements with targets of opportunity

In order to carry out data fusion, registration error correction is crucial in multisensor systems. This requires estimation of the sensor measurement biases. It is important to correct for these bias errors so that the multiple sensor measurements and/or tracks can be referenced as accurately as possible to a common tracking coordinate system. This paper provides a solution for bias estimation for the minimum number of passive sensors (two), when only targets of opportunity are available. The sensor measurements are assumed time-coincident (synchronous) and perfectly associated. Since these sensors provide only line of sight (LOS) measurements, the formation of a single composite Cartesian measurement obtained from fusing the LOS measurements from different sensors is needed to avoid the need for nonlinear filtering. We evaluate the Cramer-Rao Lower Bound (CRLB) on the covariance of the bias estimate, i.e., the quantification of the available information about the biases. Statistical tests on the results of simulations show that this method is statistically efficient, even for small sample sizes (as few as two sensors and six points on the trajectory of a single target of opportunity). We also show that the RMS position error is significantly improved with bias estimation compared with the target position estimation using the original biased measurements.
Effects of Ethanol on Drug and Metabolite Pharmacokinetics

Pharmacokinetic interactions of ethanol with other drugs, including its effects upon drug metabolite disposition, are reviewed in terms of clearance concepts. This approach is particularly useful in understanding the mechanisms of ethanol-drug interactions, i.e. in separating the effects of ethanol upon drug clearance, volume of distribution and plasma protein binding. The application of clearance concepts provides the basis for understanding the qualitative differences in ethanol interactions with low and high hepatic extraction ratio drugs. The effects of short and long term ethanol consumption upon different types of drug metabolism (oxidative, acetylation and glucuronidation) have been considered. Long term ethanol consumption may increase the clearance of a drug by induction of oxidative metabolism whereas short term consumption may decrease the clearance of such a drug. Clearance by N-acetylation appears to be increased in the presence of ethanol, and clearance by conjugation to glucuronic acid is decreased for some drugs by single-dose consumption of ethanol.
Ventilatory response to the PCO2 profile in chicken lungs.

Abstract We investigated the influence of intrapulmonary chemoreceptors (IPC) on ventilatory movements in anesthetized chickens when P CO2 profiles along the parabronchi were changed. In all experiments the right lung was denervated, both lungs unidirectionally ventilated, and Pa CO2 kept constant. In series 1 (7 birds), gas flow and the P CO2 profile in the left lung were reversed. Pa CO2 , PE CO2 and ventilatory movements did not change. In Series 2 (4 birds), P CO2 in caudal regions of the innervated lung was elevated by increasing gas flow and PI CO2 from 0 to 21 Torr. Ventilatory movements did not change. In Series 3 (4 birds), either lung was over-ventilated with 7 or 49 Torr PI CO2 , alternating the gases between lungs every 100 sec. Ventilatory movements changed with PI CO2 but much less than predicted from PI CO2 effects in the non-perfused, innervated lung. From the longitudinal distribution of IPC and P CO2 profiles in the lung we predicted moderate to large changes in ventilatory movements in all series. The discrepancy between predicted and observed results in Series 1 and 2 indicates that IPC in caudal regions of the lungs have little effect on ventilation under the conditions examined. In Series 3, observed ventilatory movements were less sensitive to PI CO2 than predicted, indicating that IPC sense a different P CO2 than the P CO2 profile in the parabronchial lumen and that IPC have a significant sensitivity to pulmonary blood P CO2 .
Softcopy display requirements for digital mammography

One of the advantages of digital mammography is to display mammograms on softcopy (electronic displays). Softcopy display of mammography is challenging because of the spatial and contrast resolution demands present in mammograms. We have designed and developed a softcopy mammography display application, Mammoview, which is capable of allowing radiologists to read mammograms as quickly and as accurately as they can on film alternators. We review the studies using Mammoview to elucidate the requirements of a successful softcopy display station. The design and development of the Mammoview softcopy display station are described in this article, and results of several studies using Mammoview are reported, including subjective feedback from Radiological Society of North America (RSNA) conference demonstrations, and clinical studies measuring performance in terms of speed and accuracy. Additional analysis of user interactions and user feedback is used to study the successes and shortcomings of mammography display stations like Mammoview. Overall, radiologist readings using Mammoview have been shown to be as fast and as accurate as readings using mammography film alternators. However, certain parts of the softcopy interface were more successful than their film counterparts, whereas others were less successful. Data analysis of the recorded human–computer interactions for the softcopy component of the clinical trial indicate statistically significant correlations between the difference in review time of softcopy versus alternator readings and three factors: the number of interactions, the reader, and the size of the image being reviewed. The first factor (number of interactions) suggests that simpler interfaces require less time to use; the second factor, the reader, supports previous findings that radiologists vary in how fast they read screening mammography studies; the third, size of image, suggests that the speed of softcopy review is increased relative to film readings when images are significantly larger than the display size. Feedback from radiologists using the system in clinical trials and at demonstration exhibits at RSNA indicated good acceptance of the interface and easy adaptation. Radiologists indicated that they felt comfortable using the interface, and that they would use such a softcopy interface in clinical practice. Finally, preliminary work suggests that the addition of a simple interaction to incorporate computer-aided detection (CAD) results would improve reading accuracy without significantly increasing reader times.
Effect of hardware alignment on fuel distribution and combustion performance for a production engine fuelinjection assembly

The hardware in a production combustor cannot be constrained within strict tolerances due to (1) manufacturing variations and (2) provisions for thermal expansion that often preclude exact alignment of all parts over the operating cycle. The demand for higher performance is directing attention to the relationship of hardware alignment to combustor performance. The present article reports on a systematic characterization of hardware alignment on both the spray structure (nonreacting) and associated combustion performance for a practical fuel-injection/swirler assembly. Planar, liquid laser-induced fluorescence (PLLIF) and phase Doppler interferometry (PDI) are utilized for the nonreacting assessment, whereas emissions and temperatures are used to characterize the reacting case. It is found that misalignment of 2.54 mm has a significant effect on the fuel distribution while having only a modest effect on the gas-phase aerodynamics and overall droplet sizes. Quantification of the fuel distribution using unmixedness indices allows for correlations between the fuel distribution and combustion performance to be established and assessed. It is found that the effect of alignment on the fuel distribution under nonreacting conditions directly translates into an impact on combustion performance in terms of mean pollutant levels and stability as well as the spatial distribution of the patterns of the pollutants at the exit plane. The study also dem-onstrates that PLLIF has a potential for screening designs relative to PDI due to its efficient application. However, the complex phenomena occurring in liquid-fired combustion systems suggests that PLLIF images are not sufficient in general, since changes in droplet size and aerodynamic structures can affect directly the combustion performance as well as the fuel distribution.
A summary of U.S. skydiving fatalities: 1993-1999.

Between 1993 and 1999, 241 people died while participating in civilian recreational skydives in the United States. A taxonomy of skydiving fatalities was developed and used to categorize the fatalities.
Recovery from adaptation to NaCl in young and elderly

Les donnees experimentales concernant l'adaptation gustative de l'homme jeune et âge en reponse a un stimulus chimique (NaCl) sont comparees a celles relatives a l'adaptation olfactive chez les sujets âges et jeunes
SU-E-T-110: Small Electron Field Surface Dosimetry Using Solid State Detectors.

Purpose: Solid state detectors from two independent systems have shown similar over‐responses to small electron fields used for treatment of surface lesions. We propose to evaluate the accuracy of solid state detector systems for highly blocked electron fields as a method for clinical dosimetry and determine the cause for any deviations from expected dose‐delivery calculations. Methods: A QED Diode detector system and a Best‐Medical MOSFET dosimeter system were used to measure relative output factors (ROF's) for a range of blocked electron fields with 3 different electron energies. Measurements were taken on the surface of a Solid‐Water phantom as well as under varying thicknesses of bolus (surface to dmax) to determine the extent of this effect with increasing depth. Measurements were compared with expected results obtained during machine commissioning with an A‐14 micro‐ionization chamber. Results:Field sizes larger than 4×4 cm2 showed little significant deviation from expected output factor values. However, fields smaller than this threshold showed as much as a 30% over‐response of the solid state detectors compared to ion chambermeasurements on the surface. This deviation was consistent over multiple measurements using both systems. The degree of over‐response is both energy and effective field size dependent. As the effective depth of measurement increases, the relative differences in responses decrease and eventually converge. Conclusions:Surfacedosimetry using solid state detectors is a straightforward method of verifying dosimetric calculations. Care must be taken when using these systems for surfacedosimetry with highly blocked fields as their non‐tissue equivalence makes these detectors overly sensitive to low‐energy scattered electrons and bremsstrahlung photons produced from the block edge. Measurements taken near dmax will not show a significant deviation from the actual dose and do not need to account for this effect.
Friction and wear properties of ion implanted and ion beam enhanced vapor deposited surfaces

A review of two specific areas in which ion implantation has been shown to improve friction and wear properties is presented. In the first area, titanium ions with energies ranging from 50 to 200 keV have been implanted into hardened steels such as AISI 52100. Significant reductions in the coefficient of friction and wear rates for a 52100 ball sliding on an implanted disk are observed if the fluence is sufficiently large that an amorphous Fe-Ti-C layer is formed in the near-surface region. The source of the carbon has been determined to be from the dissociative chemisorption of residual carbon-containing molecules onto titanium atoms uncovered at the surface by sputtering. The second area of research involves simultaneous ion bombardment during vapor deposition of titanium to produce refractory coatings. Specifically, either nitrogen or titanium ion bombardment in the energy range 15 to 30 keV has been performed simultaneous with titanium vapor deposition in the presence of a reactive nitrogen-containing gas to form a TiN compound. Very-low-friction, highly adherent coatings on 52100 steel substrates have been obtained by this technique, even though the composition of the coatings has been found to be TiNx where x < 1.
Factors Influencing the Successful Utilization of Home Health Care in the Treatment of Children and Adolescents With Cancer

Because of ongoing developments in available therapies, supportive care, and medical technology, as well as psychosocial and financial considerations, children and adolescents with cancer are undergoing a greater variety of treatments in a greater variety of settings with a greater chance for cure of their diseases than ever before. Choice of venue for various components of an individual child's treatment must take into account the nature of the therapy, available resources, and burden for the child and family. This article will review recent literature illustrating factors to be considered for the successful utilization of home care services in the overall care of children and adolescents with cancer.
3D model for TM region of the AT-1 receptor in complex with angiotensin II independently validated by site-directed mutagenesis data.

A three-dimensional model of the complex of angiotensin II (AII) with the transmembrane (TM) region of the angiotensin II receptor of type 1 (the AT-1 receptor) was obtained by molecular modeling procedures employing structural homology to the X-ray structure of rhodopsin. Since the modeling procedure considered only steric and energy considerations without prior knowledge of the experimental results of site-directed mutagenesis, the results with receptor mutants could be used for independent validation of the model. Indeed, the model brings in contact the residues of AII responsible for agonistic activity, Tyr(4), His(6), and Phe(8), with many residues of AT-1 involved in signal transduction according to site-directed mutagenesis. The model also predicts the existence of several possible conformational pathways for transferring the binding signal through the TM region of AT-1 to the intracellular loops interacting with the G-protein.
VERITAS Prototype Performance and Construction Status

VERITAS is an array of 12-m imaging air-Cherenkov telescopes dedicated to gamma-ray astronomy in the 50 GeV - 50 TeV energy band. A prototype telescope was successfully operated between September 2003 and April 2004, yielding detections of the Crab Nebula and Mrk421 blazar. Construction has begun on the full array.
Prey preparation and the determinants of handling time

Abstract Prey preparation can be a conspicuous and variable component of handling time. The swallwoing threshold model suggests that foragers prepare prey that are too large to swallow whole, and predicts that preparation is a step function of prey size. The gut encounter model suggests that preparation is a compromise between fitting more prey in the gut and maintaining high encounter rates. It predicts increasing preparation with increasing encounter rates and decreasing gut capacity. Grasshopper sparrows, Ammodramus savanarrum , are able to consume prey above the swallowing threshold through prey preparation. However, preparation is a positive, negatively accelerated exponential function of prey width. Preparation increases with encounter rate and decreased gut capacity, but in a continuous fashion not predicted by the gut encounter model. Factors contributing to the positive relation between prey size and handling time are discussed.
Design of band-gap grid structures

This paper discusses issues related to designing band-gaps in periodic plane grid structures. Finite element analysis is used to solve the dynamic behavior of a representative unit cell and Bloch–Floquet theory is used to extend the results to the infinite structure. Particular attention is given to the addition of non-structural masses that are introduced as design variables. These are used to create desirable features in the dispersion diagram. Physical insight is presented into the optimal choice of locations where masses should be added and the results of several numerical examples are provided to highlight this and other features of how band-gaps can be created and located at desired frequency ranges. The effect of the skew angle of the underlying grid structure is also explored, as are mathematical refinements of the modelling of the beam elements and the rotational inertia of the added masses. A scaling feature between the size of the reducible and the irreducible reference cell is exploited and the manner in which this can simplify optimization approaches is discussed.
Mercury cycling in agricultural and managed wetlands of California, USA: experimental evidence of vegetation-driven changes in sediment biogeochemistry and methylmercury production.

Abstract The role of live vegetation in sediment methylmercury (MeHg) production and associated biogeochemistry was examined in three types of agricultural wetlands (domesticated or white rice, wild rice, and fallow fields) and adjacent managed natural wetlands (cattail- and bulrush or tule-dominated) in the Yolo Bypass region of California's Central Valley, USA. During the active growing season for each wetland, a vegetated:de-vegetated paired plot experiment demonstrated that the presence of live plants enhanced microbial rates of mercury methylation by 20 to 669% (median = 280%) compared to de-vegetated plots. Labile carbon exudation by roots appeared to be the primary mechanism by which microbial methylation was enhanced in the presence of vegetation. Pore-water acetate (pw[Ac]) decreased significantly with de-vegetation (63 to 99%) among all wetland types, and within cropped fields, pw[Ac] was correlated with both root density (r = 0.92) and microbial Hg(II) methylation (k meth. r = 0.65). Sediment biogeochemical responses to de-vegetation were inconsistent between treatments for “reactive Hg” (Hg(II) R ), as were reduced sulfur and sulfate reduction rates. Sediment MeHg concentrations in vegetated plots were double those of de-vegetated plots (median = 205%), due in part to enhanced microbial MeHg production in the rhizosphere, and in part to rhizoconcentration via transpiration-driven pore-water transport. Pore-water concentrations of chloride, a conservative tracer, were elevated (median = 22%) in vegetated plots, suggesting that the higher concentrations of other constituents around roots may also be a function of rhizoconcentration rather than microbial activity alone. Elevated pools of amorphous iron (Fe) in vegetated plots indicate that downward redistribution of oxic surface waters through transpiration acts as a stimulant to Fe(III)-reduction through oxidation of Fe(II)pools. These data suggest that vegetation significantly affected rhizosphere biogeochemistry through organic exudation and transpiration-driven concentration of pore-water constituents and oxidation of reduced compounds. While the relative role of vegetation varied among wetland types, macrophyte activity enhanced MeHg production.
Reduced-search soft-decision trellis coding of linear block codes (Corresp.)

Algorithms for the soft-decision decoding of linear block codes are presented. These algorithms perform a reduced complexity search through a trellis derived from the parity check matrix of an (n, k) linear block code. The computational complexity of the algorithms is considerably reduced from that of a full maximum-likelihood algorithm. We demonstrate the trade-off between complexity and efficiency of the algorithms through computer simulation.
Skin conductance hypo-responding in recently abstinent cocaine dependent inpatients.

Skin conductance has been used as a measure of physiological arousal in cocaine cue reactivity studies. In this study, skin conductance responses in recently abstinent (average 3.1 &#45 1.7 days) cocaine dependent inpatients (N = 30) were assessed. A video depicting individuals preparing and using cocaine was the cue stimulus. Skin conductance responses were not increased by the stimulus cue. Several explanations are explored that may support not using skin conductance as an outcome measure in recently abstinent cocaine dependent patients.
LABOR MARKET GENDER INEQUALITY IN MINORITY GROUPS

Women's small share of professional and managerial occupations compared with their share of the total labor force is examined for the 11 largest racial and ethnic minorities in the United States. Gender-related characteristics—women's labor force participation rates, marital status, and the sex ratio—influence women's share of the top jobs, as do class and ethnic variables such as place of birth, population size, and class of worker. Labor market gender inequality is greatest among the smaller, more affluent minorities, many of whom are recent immigrants to this country. The larger, frequently indigenous, minority groups exhibit less of this kind of inequality. Minority and gender status intersect, so that men monopolize surplus resources among the more affluent minority groups and use these resources to secure a more advantaged labor market position.
Techniques for improved surface discharge switch performance

Summary form only given, as follows. Several techniques have been developed to improve the performance of surface discharge switches (i.e., SDS). These improvements will be reported in this investigation and are planned for the development of a prototype switch for the Atlas experimental facility at Los Alamos National Laboratory. One performance improvement technique consists of implanting graphite inserts in the insulator substrate to form capacitively-coupled field emission points with the underlying trigger electrode. These capacitively-coupled field emission points have reduced the trigger risetime normally required for efficient multi-channeling from 1000 V/ns to 60 V/ns. The resulting discharge has many channels and appears nearly sheet-like in nature. The improved multi-channeling allows the electrodes, which normally rest directly on the insulator surface, to be raised off the insulator surface thereby extending the lifetime of the insulator. Lifetime tests for the improved SDS has been done for 5000 commutations at 15 kV switch holdoff voltages, 750 kA peak currents, and 70 /spl mu/s wide pulses. The switch was in good condition at the end of this test and had recorded only 10 prefires during this test. To meet the switch performance requirements for the Atlas facility, further improvements in switch prefire and jitter performance can be accomplished.
Modeling the Effects of the Microporous Layer on the Net Water Transport Rate Across the Membrane in a PEM Fuel Cell

In this study, a model was developed to evaluate the effects of the microporous layer (MPL) on the net liquid water transport rate across the membrane. The results support the hypothesis that the improvement in fuel cell performance observed when an MPL is used in the cathode side is related to its effect on the water transport process in the electrode and membrane. Due to its high hydrophobicity, the MPL increases the liquid water pressure in the cathode to levels much higher than that in the anode, resulting in an increased back-transport rate of liquid water from the cathode to the anode. This reduces the amount of water that is transported out of the cathode through the gas diffusion layer (GDL) to the cathode flow channels resulting in a lower saturation level in the GDL, and consequently, faster oxygen transport to the catalyst sites. This model showed that the state of zero-net-water-transport-across-the-membrane could be achieved with the appropriate capillary properties of the porous media. Two capillary properties of the MPL identified to have the greatest impact on the proton-exchange-membrane (PEM) fuel cell performance are the liquid water saturation level at p c = 0 (p g = p l ) and the slope of the capillary curve in the hydrophobic region.
Irradiation of Neurons with High-Energy Charged Particles: An In Silico Modeling Approach.

In this work, a stochastic computational model of microscopic energy deposition events is used to study for the first time damage to irradiated neuronal cells of the mouse hippocampus. An extensive library of radiation tracks for different particle types is created to score energy deposition in small voxels and volume segments describing a neuron’s morphology that later are sampled for given particle fluence or dose. Methods included the construction of in silico mouse hippocampal granule cells from neuromorpho.org with spine and filopodia segments stochastically distributed along the dendritic branches. The model is tested with high-energy 56Fe, 12C, and 1H particles and electrons. Results indicate that the tree-like structure of the neuronal morphology and the microscopic dose deposition of distinct particles may lead to different outcomes when cellular injury is assessed, leading to differences in structural damage for the same absorbed dose. The significance of the microscopic dose in neuron components is to introduce specific local and global modes of cellular injury that likely contribute to spine, filopodia, and dendrite pruning, impacting cognition and possibly the collapse of the neuron. Results show that the heterogeneity of heavy particle tracks at low doses, compared to the more uniform dose distribution of electrons, juxtaposed with neuron morphology make it necessary to model the spatial dose painting for specific neuronal components. Going forward, this work can directly support the development of biophysical models of the modifications of spine and dendritic morphology observed after low dose charged particle irradiation by providing accurate descriptions of the underlying physical insults to complex neuron structures at the nano-meter scale.
Frontal eye field neurons signal changes in decision criteria

Flexible links between sensory stimuli and behavioral responses underlie many cognitive processes. One process that contributes to flexible decision-making is categorization. Some categories are innate or overlearned, but, in many cases, category boundaries represent flexible decision criteria that can shift on the fly to adapt to changes in the environment. The ability to shift category boundaries allows decision-making to adapt to changing circumstances. We found that monkeys were able to switch rapidly between two category boundaries when classifying the speed of a moving dot pattern and that neurons in monkey frontal eye field (FEF) changed their activity when the boundary changed. The responses of a subpopulation of FEF neurons that were sensitive to both stimulus and boundary speed were used to classify the stimuli as accurately as the monkeys' performance.