cssi/SciSciGPT-SciSciNet huggingface dataset:
Regenerative Chimerism Bioengineered Through Stem Cell Reprogramming

Regenerative medicine aims to restore damaged tissues in order to reverse disease progression and provide a sustainable solution that cures the root cause of the disease process. Although natural mechanisms of repair are ubiquitous, disruption of the homeostatic balance affects the equilibrium between health and disease due to insufficient tissue renewal in chronic degenerative conditions. Augmentation of the diseased tissue repair capacity through chimerism offers a strategy that spans all fields of medicine and surgery from natural chimerism for tissue rejuvenation, to surgical chimerism for organ replacement, to bioengineered chimerism for targeted regeneration. Technological breakthroughs in nuclear reprogramming now provide a platform to advance a broad range of solutions for regenerative medicine built on the foundation of pluripotent autologous stem cells. By optimizing the safety and effectiveness for stem cell production and ensuring tissue-specific differentiation of progenitors, induced pluripotent stem cells (iPS) offer an unprecedented opportunity to accelerate personalized applications with cell-based products to bioengineer health from disease.
Abstract W MP27: Time to Peak Troponin T Levels Following Subarachnoid Hemorrhage

Introduction: Elevations of troponin after subarachnoid hemorrhage (SAH) frequently occur and are associated with cardiopulmonary complications. The time to peak elevation remains poorly described in terms of the natural history after SAH. Our two objectives were to define the temporal profile of troponin T elevation after SAH and correlate levels of troponin T with baseline neurological status. We hypothesized that troponin T would peak early after initial presentation. Methods: We reviewed the medical records of all aneurysmal and non-traumatic SAH patients from March 2011-December 2012. Troponin T from patients with ≥ 2 values was recorded with respect to SAH symptom onset. Patients with ≥ 1 Troponin T value were stratified according to admission Glasgow Coma Scale (GCS). GCS was dichotomized to > 8 or ≤ 8. Fisher’s exact test was performed comparing elevated peak troponin T (≥0.01 ng/ml) versus normal against GCS status cutoffs > 8 or 8 or less. Results: We identified 124 patients who had both troponin T and GCS reported, and 30 patients had ≥2 troponin T measurements within the first 40 hours of hospitalization. The median time to peak troponin T in these patients was 11.2 hours with a standard deviation of 6.2 hours (Range: 4.9-35.0 hours). Elevated troponin T was seen in 52 of 124. GCS of ≤ 8 was present in 43 of 124. Patients with elevated levels of troponin T had a greater chance of lower GCS \[Odds ratio = 4.8 (95% CI: 2.2 to 10.7)\] (P= <0.0001). Conclusions: The median time to peak troponin T after SAH injury was 11 hours. There was a statistically significant association between troponin T elevation and worse neurologic status at presentation (GCS ≤ 8). Although our small sample size found large variation in time to peak troponin, it supports the hypothesis that troponin peaks early after the initial presentation. Future studies using troponin elevation as a biomarker should focus on sample acquisition at the time of admission and in the first 1-2 days. ![][1] [1]: /embed/graphic-1.gif
CMOS differential LC oscillator with suppressed up-converted flicker noise

A 1.5GHz CMOS differential VCO reduces the spectral density of up-converted flicker noise by 20dB, thereby reaching the phase noise target of -105dBc/Hz at 50kHz offset required for the PDC receive VCO. Flicker noise is suppressed by this amount across almost the entire tuning range from 1.43 to 1.64GHz, while drawing 6mA from a 2.7V supply.
An Unstable Liaison

It is well established that changes in the pattern of DNA methylation are involved in tumor formation. But whether hypomethylation or hypermethylation is the culprit is questionable. In his Perspective, Lengauer discusses intriguing new findings providing evidence that hypomethylation contributes to genomic instability leading to cancer.
Planetary Environmental Signatures for Habitability and Life

In the vast blackness of space, our home planet is a single sparkling oasis of life. Whether the Universe harbors other worlds that can support even simple life is a question that has been pondered, yet remained unanswered, for over two thousand years. Motivated by the discoveries over the past decade of hundreds of extrasolar planets, NASA and ESA have initiated a series of mission concept studies for space-based astronomical observatories that will find and study extrasolar terrestrial planets, searching for signs of life. This chapter reviews our current understanding of how we will identify planets that might support life around other stars, and incorporates results from the new science of astrobiology that support these searches
Anisotropy in the critical behavior of TTF-TCNQ and TSeF-TCNQ

We present the results of a detailed study of the critical behavior in the a and b axis resistivity of TTF-TCNQ and TSeF-TCNQ. We find that in TTF-TCNQ, dρa/dT and dρb/dT diverge as T − Tc → 0+ with the same critical exponent while in TSeF-TCNQ, dρa/dT and dρb/dT diverge with different critical exponents. These results are compared with various models for the origin of the critical behavior in the resistivity.
Medical students' comfort with children.

Summary Objective To examine the comfort level of medical students beginning their paediatric clerkships, and to identify students’ perceived concerns around interacting with children in a medical setting. Methods Prior to beginning required paediatric clerkships, third-year students in two south-eastern US medical schools completed an anonymous, 13-item questionnaire eliciting prior personal experiences with children, as well as comfort levels with selected aspects of paediatric care. Results Based on 237 responses (76.2% response rate), medical students’ total child-related experiences were significantly associated with self-assessed comfort delivering paediatric care. Female students reported more prior experiences than male medical students; however, gender was not associated with comfort working with children. A dose–response curve of experience shows a critical level of two types of experiences for comfort in working with children. Students reported significantly lower levels of comfort in performing a physical exam on a child versus obtaining a child’s medical history from a parent/caregiver. Students’ child-related experiences were significantly associated with self-assessed comfort delivering paediatric care Conclusions Medical students with little to no prior experience with children expressed significantly less comfort interacting with children in paediatric clerkships. A diversity of past experiences appeared to be a more meaningful correlate, as opposed to experience in a specific setting or context. Providing some general exposure to children during the preclinical years could instill in students greater comfort approaching their paediatric training.
Threads for Interoperable Parallel Programming

Many thread packages are freely available on the Internet. Yet, most parallel language design groups seem to have rejected all existing packages and implemented their own. This is unsurprising. Existing thread packages were designed for sequential computers, not parallel machines, and do not fit well in a parallel environment. Also importantly, existing thread packages try to impose a number of design decisions, especially in regard to scheduling and preemption. Designers of parallel languages are simply not willing to have scheduling methods decided for them, nor are they willing to allow the threads package to decide how concurrency control will work. In this paper, we explore the special issues raised when threads packages are used on parallel machines, particularly as parts of new parallel languages and systems. We describe the Converse threads subsystem, whose goals are to support the special needs of parallel programs, and to support interoperability among parallel languages. We then demonstrate how the Converse threads subsystem addresses the problems created when threads are used on a parallel computer.
Development of Portable Wireless Sensor Network System for Real-Time Traffic Surveillance

Wireless sensor network (WSN) technology is rapidly maturing and gaining momentum as an enabling technology for Internet-of-things, and Intelligent Transportation Systems (ITSs). This paper introduces the design of a novel, cost-effective intelligent vehicle counting and classification sensor system. Distinctive algorithms for vehicles detection, counting, and signature re-identification were developed and integrated. The system's integration of wireless communication, smart sensors, and intelligent algorithms is discussed in detail. Various experimental analysis scenarios are reported. A preliminary experimental study resulted in 98% accuracy for counting and detection. After system improvement in detecting class 9 vehicles by analyzing the inter-arrival time, detection accuracy reached 100%. Estimated cost of the proposed system is less than $40.
Reconceptualizing difficult groups and difficult members

Group leaders can expect to encounter group and member behaviors and attitudes that are usually termed as difficult. This article presents a different perspective that focuses on how the group leader can better understand and make visible what the troubling behavior is communicating about unspoken or unconscious needs, fantasies and desires. Suggestions for more effective interventions are proposed.
Density matrix renormalisation group Lagrangians

We introduce a Lagrangian formulation of the density matrix renormalisation group (DMRG). We present Lagrangians which, when minimised, yield the optimal DMRG wavefunction in a variational sense, both within the general matrix product ansatz and within the canonical form of the matrix product that is constructed within the DMRG sweep algorithm. Some of the results obtained are similar to elementary expressions in Hartree–Fock theory, and we draw attention to such analogies. The Lagrangians introduced here will be useful in developing theories of analytic response and derivatives in the DMRG.
A phylogenetic analysis of the emberizid sparrows based on three mitochondrial genes.

Abstract Previous molecular phylogenetic studies have examined the taxonomic relationships among a number of typical emberizid sparrow genera. To help clarify these relationships, we sequenced a 1673 base pair fragment for the complete sequence of three mitochondrial genes: adenosine triphosphatase (Atp8 and Atp6) and cytochrome oxidase subunit III (COIII) for 38 sparrow species, along with Passerina amoena (Cardinalidae) and Piranga ludoviciana (Thraupidae) which were selected as the outgroups. Our analysis confirms the monophyly of traditional genera such as Junco, Melospiza, and Zonotrichia. Although Calcarius and Plectrophenax are often thought to be putative emberizids, all our analyses placed these genera basal to all other sparrows examined. As observed with Calcarius, Spizella did not form a monophyletic group, with S. arborea being the sister-taxon to Passerella iliaca. Our analyses also suggest that Aimophila ruficeps is probably more closely related to the “brown towhees” (Pipilo aberti, P. crissalis, and P. fuscus) than its putative congeners. The genus Ammodramus was also not monophyletic, since it appears that Passerculus sandwichensis is more closely related to A. henslowii and A. leconteii then either one is related to its congener A. savannarum. Finally, our analyses exhibited other unsuspected associations, such as the sister-taxon relationships between Amphispiza bilineata and the Chondestes grammacus/Calamospiza melanocorys clade, and Amphispiza belli and Pooecetes gramineus.
Isothermal decomposition of uranium hydride

Abstract We have investigated two related dynamic properties of the U-H system. In part of the work reported here, we determined dynamic pressure-composition-temperature (P-C-T) properties of uranium hydride in the temperature range 375–525 °C. We also investigated the pressure-dependent kinetics and mechanism of the decomposition of uranium hydride in the range 390–500 °C. From the functional time dependence and the functional pressure dependence of the decomposition, we conclude that the reaction is controlled by the rate of advance of the metal-metal hydride phase boundary. The decomposition has an activation energy of 18.9 ± 1.8 kcal mol−1 and the reaction has a ln( P 0 P ) pressure dependence, where P0 is the corresponding dynamic P-C-T plateau pressure.
A note on commuting pairs of matrices

We give a short proof of the Motzkin-Taussky result that the variety of commuting pairs of matrices is irreducible. An easy consequence of this is that any two generated commutative subalgebra of n×n matrices has dimension at most n. We also answer an old question of Gerstenhaber by showing that the set of commuting triples of n×n matrices is not irreducible for n≥32.
Stress analyses of four prefabricated posts

A two-dimensional photoelastic stress analysis method was applied to study the relative magnitude of stress and concentration induced by four commercially available posts for endodontically treated teeth. Three types of threaded posts; VLock, Radix Anchor, and Flexi-Post, and one nonthreaded prefabricated post, the Para-Post Plus post were tested. Stress was recorded at installation, at vertical and inclined load, and the threaded posts were compared with the nonthreaded post. At installation and on loading, stress was induced where posts were in contact with the model. Higher apical stresses were demonstrated for the Para-Post Plus post whereas the threaded posts concentrated stress where they engaged the model through threads or flanges.
Gastric cancer etiology: A biochemical hypothesis

Abstract We have proposed a two-stage biochemical model for the etiology of “intestinal” gastric cancer. The model postulates that the gastric mucosal barrier is biochemically pierced as a result of chemical interactions between the mucoproteins and mucopolysaccharides of the barrier and ingested polysaccharrides (starches). This would allow the growth of gastric flora which could produce carcinogenic nitrosamines and/or nitrosamides. Observational and experimental evidence in favor of the model is provided. The model suggests various research initiatives, the results of which might provide the basis for biochemical and physiological methods for the prevention and/or treatment of gastric cancer. Various ways in which the model may be tested are also noted.
Three-Axis Gimbal Surveillance Algorithms for Use in Small UAS

An active three-axis gimbal system is developed to allow small fixed wing Unmanned Aircraft Systems (UAS) platforms to estimate accurate position information by pointing at a target and also to track a known target location. Specific targets vary from a stationary point on the ground to aircraft in the national airspace. The payload developed to accomplish this at the University of North Dakota is the Surveillance by University of North Dakota Observational Gimbal (SUNDOG). This paper will focus on a novel, nonlinear closed form analytical algorithm developed to calculate the exact rotation angles for a three-axis gimbal system to point a digital imaging sensor at a target, as well as how to estimate accurate position of a target by using the pointing angles of a three-axis gimbal system. A kinematic analysis is done on a three-axis gimbal system to get the appropriate model of gimbal rotations in order to point at a certain location on the ground. The mathematical model includes an inertial coordinate system that has coordinates fixed to the Earth, a coordinate system that is body-fixed to the aircraft, and a third coordinate system that is fixed to the gimbal. Therefore, multiple three-dimensional transformations are required to accurately provide the necessary pointing angles to the gimbal system. The autonomous control system uses Global Positioning System (GPS), Inertial Measurement Unit (IMU), and other sensor data to estimate position and attitude during flight. Since the algorithm is entirely based on Inertial Measurement Unit (IMU) and Global Positioning System (GPS) device inputs, any error from these devices cause offset in the target location. Hence, an error analysis is carried out to find the offset distance and the operating range of the algorithm. The main advantage obtained in the three-axis gimbal system is that the orientation of the image will always be aligned in a specified direction for effective interpretation. The closed form expressions to the non-linear transformations provide simple solutions easily programmed without large computational expense. Experimental work will be carried out in a controlled environment and in flight testing to show the autonomous tracking ability of the gimbal system. Simulation and experimental data illustrating the effectiveness of the surveillance algorithms is presented.Copyright © 2008 by ASME
Compression in the Treatment of Leg Telangiectasia: Theoretical Considerations

. Unwanted leg veins are a common affliction of men and women. They may be either varicose and symptomatic or telangiectatic and of mostly cosmetic concern. Since patients wishing cosmetic improvement commonly present for treatment, one should utilize a technique that produces the least number of adverse sequelae. The use of compression in performing sclerosing treatment for varicose veins produces 5-year follow-up results similar to surgical treatments. This article presents theoretic reasons for advocating the use of compression in the treatment of all blood vessels, whether telangiectatic or varicose.
Federated database management system: requirements, issues and solutions

Abstract The use of database management systems (DBMS) to replace conventional file processing systems has dramatically increased in the past years. Although the use of DBMSs overcomes many of the limitations of file processing systems, many important applications require access to and integration of information among several and often incompatible DBMSs. In this paper we discuss an approach, known as the federated database approach, that allows users and applications to access and manipulate data across several heterogeneous databases while maintaining their autonomy. We discuss the requirements and objectives of a federated database management system, and outline the major issues and challenges for building and using such a system. In particular, we address the design issues from three angles: transaction management, system architecture, and schema integration. Also, we present a five-step integration methodology followed by a comprehensive example to illustrate the concepts and techniques involved in this integration methodology.
Central representation and somatotopic organization of the jaw muscles within the facial and trigeminal nuclei of the pigeon (Columba livia)

The location of facial and trigeminal brainstem motoneurons innervating the jaw muscles of the pigeon has been determined, using the technique of retrograde transport of horseradish peroxidase. Trigeminal motoneurons innervating the jaw closing muscles are located within the classically defined main trigeminal motor nucleus, and their organization exhibits approximately a mediolateral somatotopy. Trigeminal neurons innervating the opener muscle of the upper jaw are also located in the main trigeminal motor nucleus, but comprise a dorsomedial subnucleus which is continuous caudally with the dorsal facial nucleus whose neurons innervate the opener muscle of the lower jaw. The Vth and VIIth motor nuclei are thus linked in the rostrocaudal plane. The representations of other head muscles are arranged in a dorsoventral manner within the V–VII motor complex, with the lower eyelid muscle represented most dorsally and the hyoid and superficial neck muscles most ventrally. Jaw closing muscles were well represented in both the Gasserian ganglion and trigeminal mesencephalic nucleus. No such representation was found for either of the jaw opening muscles. The HRP data indicate that the V–VII motor complex in birds is far more extensive than has previously been suggested.
Detection of pulsed absorber using phase modulation spectroscopy

Characteristics of a system of interest can be analyzed by studying the system response to a particular input. NIR spectroscopy frequently uses an impulse (time resolved spectroscopy, TRS) and a sinusoidally modulated wave input (phase modulated spectroscopy, PMS). In this paper, we describe the theoretical principle of phase change in PMS measurement due to the heterogeneity. The phase change in a dynamic system is studied experimentally by using an experimental model and simple physiological systems.
THE PHOTOCHEMISTRY OF 5‐METHYLCYTOSINE AND 5‐METHYL‐2′‐DEOXYCYTIDINE IN AQUEOUS SOLUTION

Abstract The nucleobase 5-methylcytosine (I) is a minor component of eukaryotic DNA thought to be important in regulation of gene expression. The photochemical reactions of this nucleobase and its 2′-deoxyribonucleoside, 5-methyl-2′-deoxycytidine (II), in water have been studied. These reactions lead, respectively, to 3-amino-2-methylacrylamidine (Ib) and 3-(2-erythro-d-pentopyranos-1-yl) amino-2-methylacrylamidine (IIb) as the main photoproducts. The structure of the photoproducts was established by spectroscopic methods (1H and 13C NMR, UV spectroscopy, electron impact and liquid secondary ion mass spectrometry); in the case of Ib, confirmatory evidence was obtained by chemical methods (photolysis of 5-methyl[2–13C]cytosine, hydrolysis of N-carbomethoxy-3-amino-2-methylacryl-amidine and reaction of Ib with 1,1′-carbonyldiimidazole to give I). The quantum yield for formation of Ib was determined to be 1.8 × 10-3at pH 7.5 while the quantum yield for formation of IIb has a lower value of 0.2 × 10-3 at pH 7.5. These quantum yields depend strongly on pH and reach maximum values of 2.0 × 10-3 at pH 7.0 (Ib) and 0.6 × 10-3 at pH 5.0 (IIb). The mechanism of formation of Ib (or IIb) is proposed to involve nucleophilic attack of water on the C-2 position of photoexcited I (or II), followed by ring opening and decarboxylation of an intermediate carbamic acid.
The effects of prostaglandin E1 on the systemic and pulmonary circulations of intact dogs. The influence of urethane and pentobarbital anesthesia.

Es wird gezeigt, dass Phenobarbital- und Urethan-Anasthesie nach Infusion von PGE1 in den Kreislauf normaler Hunde verschiedene hamodynamische Reaktionen (Herzminutenvolumen, Herzfrequenz, Durchblutung der Peripherie) verursacht.
A study of basicity of tri- and tetrametaphosphate and the stability of their complexes with copper(II) by means of the glass pH and the dropping amalgam electrodes—I

Abstract From the slight lowering of pH of a strong acid in the presence of trimetaphosphate ion, it was shown that only one hydrogen ion is partially associated corresponding to pK3 value of 0·65±0·10, at 25° and an ionic strength adjusted to unity with tetramethylammonium nitrate. A somewhat greater lowering of pH in the presence of tetrametaphosphate ion indicated a greater degree of association of one hydrogen ion corresponding to a pK4 of 1·53±0·08. The anodic-cathodic polographic waves of copper tri- and tetrametaphosphate complexes obtained with a droping amalgam electrode, 0·0005 per cent in copper by weight, are essentially reversible. They are perfectly continuous and have slopes of about 0·032. The stabilities of the complexes have been determined from the shift in potential due to complex formation. At 25° with the ionic strength adjusted to unity with N(CH3)4NO3, two trimetaphosphate ions can be bound in complexes with a copper(II) ion for which the logarithms of the formation constants are 1·58±0·10 and 0·60±0·20. Two tetraphosphate ions can be bound more strongly in a complex with a copper(II) ion for which the logarithms of the stepwise formation constants are 3·04±0·03 and 1·24±0·05, respectively. The stronger bonding of both hydrogen and copper(II) ions by the latter is probably due to its greater flexibility.
Next-Generation Bioimaging Systems

The question I would like to help answer is: What is the role and what can imaging do for systems biology? In recent years, the focus in biological sciences has shifted from understanding single parts of larger systems, sort of vertical approach, to understanding complex systems at the cellular and molecular levels, horizontal approach. Thus the revolution of "omics" projects, genomics and now proteomics. Understanding complexity of biological systems is a task that requires acquisition, analysis and sharing of huge databases, and in particular, high-dimensional databases. For example, in the current project on location proteomics, the fluorescence microscopy data sets can have a dimension as high as 5: two spatial dimensions, z-stacks, time series and different-color channels (different color probes for different proteins). Processing such huge amount of bioimages visually by biologists is inefficient, time-consuming and error-prone. Therefore, we would like to move towards automated, efficient and robust processing of such bioimage data sets. Moreover, some information hidden in the images may not be readily visually available. For example, in the same project, we use images of two proteins residing in the Golgi apparatus-giantin and gpp130. These two proteins cannot be distinguished better than randomly by humans, while when employing data mining methods, they can be told apart. Therefore, we do not only replace humans by machines for faster and more efficient processing but also because new knowledge is generated through use of sophisticated algorithms. The ultimate dream is to have distributed yet integrated large bioimage databases which would allow researchers to upload their data, have it processed, share the data, download data as well as platform-optimized code, etc., and all this in a common format, something akin to the DICOM format for clinical imaging. To achieve this goal, we must draw upon a whole host of sophisticated tools from signal processing, machine learning and scientific computing. While such tools are widely present in clinical (medical) imaging, they are not as widespread in imaging of biological systems at cellular and molecular levels. This is a huge challenge and requires integration of interdisciplinary teams. I will address some of these issues in this presentation
The magic number nine‐atom alkali halide cluster ion. Is the nine‐atom planar structure the most stable?

The question of whether the cubic structures proposed for the alkali halide cluster ions are the most stable has been re-examined. Geometry/energy optimization calculations were performed on other candidate structures for the [M(MX)4]+ species. The square-planar structure was found to be more than 3 eV lower in energy than a proposed quasi-octahedral structure. The relative energies of the square-planar and other structures for a series of nine-atom alkali halide cluster ions are found to correlate with published experimental data.
Long-Slit Observations of Extended C II 1335 Emission Around V854 Centauri and RY Sagittarii

We have obtained long-slit far-ultraviolet (1150--1730 A) spectra of the R Coronae Borealis (RCB) stars V854 Cen and RY Sgr, near maximum light and pulsational phase zero, with the Space Telescope Imaging Spectrograph (STIS) on Hubble Space Telescope (HST). The far-UV spectrum of each star shows a photospheric continuum rising steeply toward longer wavelengths, and a prominent emission feature at C II 1335. RY Sgr displays a second, but fainter, emission attributed to Cl I 1351 (which is radiatively fluoresced by C II 1335), but Cl I is weak or absent in V854 Cen. Most surprisingly, the C II emission of V854 Cen is significantly extended along the slit by +/- 2.5 arcsec, about 6 x 10^3 AU at the distance of the star. The C II feature of RY Sgr exhibits no such gross extension. Nevertheless, subtle broadenings of the C II emissions beyond the point response profile suggests inner clouds of radius \~0.1 arcsec (250 AU) around both stars. V854 Cen is only the third RCB star after R CrB and UW Cen known to have a resolved shell.
Cognitive-behavioral treatment of childhood depression

There has been a recent surge of interest in the topic of childhood depression. Whereas much has been written about diagnosis of childhood depression, far less attention has been devoted to the treatment of this condition. The limited knowledge base about intervention approaches to childhood depression stems from the recency of interest in this condition and its imprecise definition. Models for the treatment of childhood depression arise largely from treatment models of adult depression, because the two conditions are seen as similar. This paper reviews the assumptions, potential uses and misuses, research base, and developmental goodness of fit of behavioral and cognitive approaches to the treatment of childhood depression. Empirical data, as well as rational analysis based on developmental considerations, are used in evaluating the merits of the various therapeutic approaches. Implications for school psychologists are discussed.
Cue-Evoked Cocaine “Craving”: Role of Dopamine in the Accumbens Core

Drug-associated cues can acquire powerful motivational control over the behavior of addicts, and can contribute to relapse via multiple, dissociable mechanisms. Most preclinical models of relapse focus on only one of these mechanisms: the ability of drug cues to reinforce drug-seeking actions following a period of extinction training. However, in addicts, drug cues typically do not follow seeking actions; they precede them. They often produce relapse by evoking a conditioned motivational state (“wanting” or “craving”) that instigates and/or invigorates drug-seeking behavior. Here we used a conflict-based relapse model to ask whether individual variation in the propensity to attribute incentive salience to reward cues predicts variation in the ability of a cocaine cue to produce conditioned motivation (craving) for cocaine. Following self-administration training, responding was curtailed by requiring rats to cross an electrified floor to take cocaine. The subsequent response-independent presentation of a cocaine-associated cue was sufficient to reinstate drug-seeking behavior, despite the continued presence of the adverse consequence. Importantly, there were large individual differences in the motivational properties of the cocaine cue, which were predicted by variation in the propensity to attribute incentive salience to a food cue. Finally, a dopamine antagonist injected into the nucleus accumbens core attenuated, and amphetamine facilitated, cue-evoked cocaine seeking, implicating dopamine signaling in cocaine cue-evoked craving. These data provide a promising preclinical approach for studying sources of individual variation in susceptibility to relapse due to conditioned craving and implicate mesolimbic dopamine in this process.
Changes in Nucleosome Occupancy Associated with Metabolic Alterations in Aged Mammalian Liver

SUMMARY Aging is accompanied by physiological impairments, which, in insulin-responsive tissues, including the liver, predispose individuals to metabolic disease. However, the molecular mechanisms underlying these changes remain largely unknown. Here, we analyze genome-wide profiles of RNA and chromatin organization in the liver of young (3 months) and old (21 months) mice. Transcriptional changes suggest that derepression of the nuclear receptors PPARa, PPARg, and LXRa in aged mouse liver leads to activation of targets regulating lipid synthesis and storage, whereas age-dependent changes in nucleosome occupancy are associated with binding sites for both known regulators (forkhead factors and nuclear receptors) and candidates associated with nuclear lamina (Hdac3 and Srf) implicated to govern metabolic function of aging liver. Winged-helix transcription factor Foxa2 and nuclear receptor corepressor Hdac3 exhibit a reciprocal binding pattern at PPARa targets contributing to gene expression changes that lead to steatosis in aged liver.
Fission-spectrum neutrons at reduced dose rates enhance neoplastic transformation

We have studied the effect of reduced dose rates of radiation on neoplastic transformation using the C3H/1OT1/2 mouse embryo-derived cell line developed by Reznikoff et al.1. In this cell system, transformation can be measured by scoring the foci of piled-up cells that occur after the loss of contact inhibition of growth. We report here that reduction of the dose rates of fission-spectrum neutrons (of mean energy 0.85 MeV) from 38.5 or 10.3 to 0.43 and 0.086 rad min−1 has no effect on cell killing but increases transformation frequency. These data are in contrast to previously published results obtained with 60Co γ rays where reduction of the dose rate resulted in a marked reduction in transformation frequency2,3. Although cancer induction in man involves many factors besides those at the cellular level, the implication from our findings is that the risk of cancer induction due to work-related exposure to neutrons in the nuclear power industry may be greater than previously thought.
The Continuous Flow Condensation Nucleus Counter. II

The original version of the continuous flow counter has been improved and redesigned to run automatically with a rotary sequencing valve and data processing system. As previously described, the counter was developed at the Environmental Measurements Laboratory for use with diffusion batteries because they require a constant flow of aerosol for particle size measurement. The automated system is used extensively for measurement of the concentration and particle size distribution of indoor and outdoor aerosols. The operating conditions are evaluated to determine the effect of temperature deviation and alcohol dilution. Laboratory measurements of both the dew point and the light transmission show the diameter of the alcohol drops to vary from 13 μm at nucleus concentration of 1000/cm3 to 5.5 μm at 300,000/cm3. A recent calibration shows the new counter to be nearly 100% efficient for condensation nuclei ranging from 90 to 5 nm in diameter.
Toward Integrative Tourism Planning in Rural America

There is a need to develop planningframeworks that address tourism development within the broader context of community or regional development goals in rural areas of the United States. An integrative approach is one such framework that entails careful assessment of economic, social, and environmental impacts of tourism relative to other development strategies. This review takes a historical perspective of rural tourism planning progress. Core concepts of an integrative approach are collaborative planning with the affected stakeholders and the assessment of specific planning issues that foster integration of tourism with overall regional development. The application of more integrativeframeworks allows planners to improve the manner in which rural tourism development occurs.
Infertile bulls versus steers: IV. Meat quality

Meat quality comparisons were made between a total of 43 infertile bulls and 42 steers in five separate trials. Tenderness, juiciness and flavour were tested by taste panel for each of the five trials, making 15 subjective tests, while objective tests were made of tenderness (Warner-Bratzler shear) and juiciness (industrial press) in the five trials, making a further ten tests. From this total of 25 different groups of assessments no significant difference between bull and steer meat was detected in 21; of the four groups of assessments where significant differences were detected, two favoured the bulls and two favoured the steers; the quality of all the samples was acceptable. It is concluded from the overall results that in terms of practical meat quality there was no difference between the bulls and steers used in these five trials.
Sonographs of submarine sediment failure caused by the 1980 earthquake off northern California

In 1980, a large earthquake caused extensive sediment failure on the shallow continental shelf off the Klamath River in northern California. Side-scan sonography was used to complement detailed geophysical profiling in identifying specific features and resolving modes of failure. The features include a nearly flat failure terrace mantled with sand boils, collapse craters and sediment flows, and bounded on the seaward side by a meandering continuous toe ridge. Seaward of the terrace lies a compression zone delineated by small pressure ridges. Our findings indicate a temporal progression of failure from lique-faction of shallow subsurface sand to lateral spread of intact blocks to sediment collapse and flow.
Free field theories of spin-mass trajectories and quantum electrodynamics in the null plane

The ten generators of the Poincare algebra for quantum electrodynamics and other gauge theories are given in the null plane. The explicit correspondence of their field-theoretic form to the Bacry-Chang group-theoretic form in the free case is pointed out. It is then noticed that the forms are independent of the spin and allow inclusion of charge quantum numbers at will, which indicates that they represent an advantageous free-particle starting point for a hadron theory with positive spin-mass trajectories (SMT) and with interaction. The internal oscillator content is extracted for both gauge theories and dual resonance models. Interactions are cubic and quartic in the fields. In the dual model they encompass the SMT, whereas no straightforward extension to SMT is possible for the manifestly covariant theories. The requirements of a field-theoretic SMT interaction are spelled out in an algebraic form which guarantees Poincare invariance; however no such interaction is yet known. The approach indicates how a realistic spectrum might be achieved without composite hadrons and incorporating full Poincare invariance.
Comparison of adenosine, isoflurane, and desflurane on myocardial tissue oxygen pressure during coronary artery constriction in dogs

Abstract Objective: To compare adenosine-, isoflurane-, or desflurane-induced hypotension with and without left anterior descending (LAD) coronary artery constriction for the effects on myocardial tissue oxygen pressure (PmO2) in dogs. Design: Prospective, randomized, nonblinded. Setting: University teaching hospital. Participants: Male nonpurpose-bred dogs (n = 18). Interventions: Dogs were anesthetized with 1.5% isoflurane (n = 12) or 8% desflurane (n = 6). A flow probe and balloon occluder were placed on the LAD artery. A probe that measured myocardial oxygen pressure was inserted into the middle myocardium in the LAD region. Myocardial oxygen consumption (MVO2) was calculated as LAD flow x arterial minus coronary sinus oxygen content. Measures and Main Results: Measures were made during hypotension produced by adenosine infusion, 2.8% isoflurane, or 14% desflurane with and without LAD constriction to decrease blood flow 30%. Without LAD artery constriction, adenosine infusion increased LAD flow 90% and MVO2 70%, 2.8% isoflurane produced no change in MVO2, and 14% desflurane decreased MVO2 25%, but no treatment changed PmO2. LAD artery constriction decreased PmO2 50% by itself. Adenosine infusion during LAD constriction decreased tissue oxygen pressure an additional 60%, 2.8% isoflurane produced no change, and 14% desflurane increased PmO2 100%. Conclusion: There was an inverse relationship between the effect of adenosine, 2.8% isoflurane, and 14% desflurane on MVO2 and PmO2 during ischemia. This is consistent with reports that increasing oxygen demand worsens myocardial ischemia.
Reasons-responsiveness and degrees of responsibility

Ordinarily, we take moral responsibility to come in degrees. Despite this commonplace, theories of moral responsibility have focused on the minimum threshold conditions under which agents are morally responsible. But this cannot account for our practices of holding agents to be more or less responsible. In this paper we remedy this omission. More specifically, we extend an account of reasons- responsiveness due to John Martin Fischer and Mark Ravizza according to which an agent is morally responsible only if she is appropriately receptive to and reactive to reasons for action. Building on this, we claim that the degree to which an agent is responsible will depend on the degree to which she is able to recognize and react to reasons. To analyze this, we appeal to relations of comparative similarity between possible worlds, arguing that the degree to which an agent is reasons-reactive depends on the nearest possible world in which given sufficient reason to do otherwise, she does so. Similarly, we argue that the degree to which an agent is reasons-receptive will depend on the intelligibility of her patterned recognition of reasons. By extending an account of reasons-responsiveness in these ways, we are able to rationalize our practice of judging people to be more or less responsible.
Application of rough hard sphere theory to diffusion in supercritical fluidst

Abstract The limiting mutual diffusion coefficients of benzene and carbon tetrachloride were measured in subcritical and supercritical carbon dioxide at 298 and 309 K in the pressure range 8.96 – 26.0 MPa using the Taylor dispersion technique. The rough hard sphere theory was used for interpretation of the data obtained in this study as well as the data in the literature for limiting and self-diffusion coefficients. The theory represents the data successfully for pure fluids with a density-independent coupling parameter. The effective hard sphere diameters extracted from the data match closely with the diameters calculated by other methods. The same functional dependence of the self-diffusion coefficients on molar volume was also observed for limiting mutual diffusion coefficients determined in this work and for naphthalene data in the literature. Hence, a correlation based on the rough hard sphere theory was developed for prediction of diffusivities in sub- and supercritical carbon dioxide. The correlation reproduces the data with an average absolute deviation of 7.68%.
The uses of program reading

It is argued that program reading is an important programmer activity and that reading skill should be taught in programming courses. Possible teaching methods are suggested. The use of program reading in test construction and as part of an overall teaching strategy is discussed. A classification of reading comprehension testing methods is provided in an appendix.
Parathyroid hormone (PTH)-induced intracellular Ca2+ signalling in naive and PTH-desensitized osteoblast-like cells (ROS 17/2.8): pharmacological characterization and evidence for synchronous oscillation of intracellular Ca2+.

We showed recently that the initial peak cytosolic ionized calcium ([Ca2+]i) response to PTH (2-min exposure) is preserved relative to the cAMP response in osteoblast-like rat osteosarcoma cells (ROS 17/2.8) desensitized by 72-h exposure to PTH. We attempted in the present studies to determine the mechanisms for preservation of the [Ca2+]i response and to explore the effects of longer PTH rechallenges. The [Ca2+]i; response to a 20-min perifusion with rat PTH [rPTH-(l–34)] was monitored by aequorin luminescence in both naive and PTH-desensitized ROS 17/2.8 cells. The responses of both naive and desensitized cells consisted of two phases: an initial peak, followed by an intermediate plateau that was sustained in the presence of PTH. We observed in the naive cell populations synchronous oscillations in [Ca2+]i concentration during this second phase (amplitude, 10β60 nm; frequency, 1β3/100 sec). These oscillations were maintained through extracellular calcium (EC Ca2+) entry; the initial peak was the result ...
Current evidence for a role of glucose as a regulator of hypothalamic function and caloric homeostasis.

Abstract Current evidence that glucose may regulate hypothalamic function and feeding behavior is reviewed. It is suggested that (1) blood levels of glucose/insulin may serve as a control signal influencing a variety of hypothalamic functions—control of feeding behavior, insulin secretion, hepatic glucose release, fat mobilization—that maintain caloric homeostasis; (2) hormones, such as estrogen, that modulate feeding may do so by altering hypothalamic sensitivity to that control signal (glucose/insulin); and (3) fluctuations in the magnitude of that control signal (glucose/insulin) due to changes in overall metabolism may be a means whereby hypothalamic function is adjusted to meet changing metabolic requirements.
SLIDING ROCKS AT THE RACETRACK, DEATH-VALLEY - WHAT MAKES THEM MOVE

Sharply angular boulders as large as 320 kg sit on the Racetrack Playa, Death Valley, California; trails leading to them indicate that the rocks have moved large distances. The process has never been witnessed. Although high winds and a wetted surface seem necessary, controversy persists about the need for other conditions, especially ice sheets. On the basis of experiments with a wetted Racetrack surface (soft mud ∼3 cm deep), we find the effective coefficient of friction to be surprisingly high, ∼0.8. Movement by wind alone of moderate-sized (20 kg) rocks with cubic shape requires sustained winds close to the ground of ∼80 m/s (∼180 mph). Larger flat-lying rocks require much higher winds. To assess the ice-sheet hypothesis, we mapped a large number of tracks into a precise coordinate system with an electronic theodolite. Certain tracks, separated by <1 to ∼830 m, have nearly identical curving patterns near their starts. The distance between a distinctive bend on one such track and its mate on another matches the distance for another mated pair of bends on these same tracks within several centimetres, even for tracks 830 m apart. As proposed by Stanley (1955), it seems that the rocks, resting on mud, were locked into a single floating ice sheet, in this case at least 850 X 500 m. Final resting places of these rocks are much more widely scattered than their starting points, suggesting that the sheet broke into smaller plates. Large ice sheets can move rocks even with light winds and may explain the gentle curvature of tracks hundreds of metres long, a pattern very unlikely with gusty high winds and no ice.
Motivating students with a historical perspective in financial accounting courses

Abstract This article provides historical “nuggets” as diverse, random examples that the authors have used for introducing particular intermediate and advanced financial accounting topics. This approach gives students historical experience with topics that would be rather dull to discuss without the historical context. A historical perspective need not be used to introduce each and every topic; indeed, if instructors were to do that, the motivational effect could conceivably wane throughout the course. Instructors should experiment with historical examples with an eye to: (a) explaining concepts that students often view as abstract, (b) stressing interrelationships among concepts, and (c) emphasizing how accounting changes reflect environmental changes.
An active-site titration method for immobilized trypsin.

Abstract An active-site titration method for immobilized trypsin with p-nitrophenyl p′-guanidinobenzoate (NPGB) employing a recirculation reactor system is described. Trypsin, covalently linked to 35 and 150 μm diameter porous glass particles was titrated by this procedure, analyzed for protein content, and then compared with soluble trypsin. Analysis of the titration results indicates that the amount of p-nitrophenol produced by the burst is equal to the amount of active immobilized trypsin. This active site titration determines the absolute amount of active immobilized enzyme and is preferable to either total protein analysis or kinetic assays for characterization of immobilized enzymes.