cssi/SciSciGPT-SciSciNet huggingface dataset:
SU-E-T-627: Optimal Partial Arcs in VMAT Planning.

Purpose: To describe a method for producing minimal delivery time partial arc VMAT plans. Methods: We begin with the assumption that dose quality is the primary treatment planning goal. Therefore the first step in the partial arc computation is a 180 beam equi‐spaced IMRT multi‐criteria optimized treatment plan, which serves as an ideal plan, along with a set of user‐ specified allowable deviations from this plan. This defines a set of target coverage and healthy organ sparing constraints. We then seek a partial arc plan which recovers this ideal plan but is minimal in delivery time. The search for the optimal partial arc which fulfills the hard constraints is done by wrapping a VMAT fluence map optimization/merging/simplification algorithm called VMERGE. The search is performed over all possible partial arcs, with start and end locations discretized to 20 degree increments, and respecting that the gantry cannot pass underneath the couch. This results in 169 partial arcs. For the ones that yield feasible plans, the complete VMERGE algorithm is run, which minimizes the delivery time for that arc. The minimal delivery time plan that fulfills the dosimetric requirements is returned. Results: We apply the method to a lung and liver case. The time savings are as follows: (full arc time, optimal partial arc time): lung (185 s, 94 s), liver (263 s, 165 s). The optimal arc for the lung lesion, a left anterior target, is 140 degrees centered at 50 degrees. The optimal arc for the liver lesion is 160 degrees centered at −90 degrees. Conclusions: By wrapping a fast VMAT optimization/sequencing routine by an exhaustive search over 169 possible partial arcs, we are able to determine the fastest delivery partial arc. The use of partial arcs can significantly shorten delivery time in VMAT delivery. The project described was supported by Award Number R01CA103904 from the National Cancer Institute. The content is solely the responsibility of the authors and does not necessarily represent the ocial views of the National Cancer Institute or the National Institutes of Health.
Lactate studies of the dog in oligemic shock.

Abstract Experiments with the graded hemorrhage shock model showed a direct relationship between bleeding and intracellular lactate. There was also a linear relationship between intracellular and extracellular lactate concentrations until reinfusion, when an increase in serum lactate with a decrease in intracellular lactate was noted. All elevations in lactate were significantly reduced by the use of vasodilators at strategic intervals.
FOXO3a Regulates Glycolysis via Transcriptional Control of Tumor Suppressor TSC1

Akt signal transduction induces coordinated increases in glycolysis and apoptosis resistance in a broad spectrum of cancers. Downstream of Akt, the FoxO transcription factors regulate apoptosis via Bim, but the contributions of FoxOs in regulating Akt-induced glycolysis are not well described. We find that FoxO3a knockdown is sufficient to induce apoptosis resistance in conjunction with elevated glycolysis. Glycolysis in FoxO3a-deficient cells was associated with increased S6K1 phosphorylation and was sensitive to rapamycin, an inhibitor of the mTORC1 pathway that has been linked to glycolysis regulation. We show that mTORC1-dependent glycolysis is increased in FoxO3a knockdown cells due to decreased expression of the TSC1 tumor suppressor that opposes mTORC1 activation. FoxO3a binds to and transactivates the TSC1 promoter, indicating a key role for FoxO3a in regulating TSC1 expression. Together, these data demonstrate that FoxO3a regulates glycolysis downstream of Akt through transcriptional control of Tsc1.
Assessing the Efficacy of Treatment for Adolescent Sex Offenders: A Cross-Over Longitudinal Study:

Though many treatment programs for adolescent sexual offenders identify specific clinical goals such as the reduction of cognitive distortions, the enhancement of sexual knowledge, the development ...
Selective mRNA Degradation by Polynucleotide Phosphorylase in Cold Shock Adaptation in Escherichia coli

Upon cold shock, Escherichia coli cell growth transiently stops. During this acclimation phase, specific cold shock proteins (CSPs) are highly induced. At the end of the acclimation phase, their synthesis is reduced to new basal levels, while the non-cold shock protein synthesis is resumed, resulting in cell growth reinitiation. Here, we report that polynucleotide phosphorylase (PNPase) is required to repress CSP production at the end of the acclimation phase. A pnp mutant, upon cold shock, maintained a high level of CSPs even after 24 h. PNPase was found to be essential for selective degradation of CSP mRNAs at 15 degrees C. In a poly(A) polymerase mutant and a CsdA RNA helicase mutant, CSP expression upon cold shock was significantly prolonged, indicating that PNPase in concert with poly(A) polymerase and CsdA RNA helicase plays a critical role in cold shock adaptation.
Use of the Dichotic Listening Technique with Learning Disabilities.

Abstract Dichotic listening (DL) techniques have been used extensively as a non-invasive procedure to assess language lateralization among children with and without learning disabilities (LD), and with individuals who have other auditory system related brain disorders. Results of studies using DL have indicated that language is lateralized in children with LD and that the lateralized language asymmetries do not develop after age 6 nor are they affected by gender. Observed differences in lateralized language processes between control children and those with LD were found not due to delayed cerebral dominance, but rather to deficits in selective attention. In addition, attention factors have a greater influence on auditory processing of verbal than nonverbal stimuli for children with LD, and children with LD exhibit a general processing bias to the same hemisphere unlike control children. Furthermore, employing directed attention conditions in DL experiments has played an important role in explaining learning disabled children’s performance on DL tasks. We conclude that auditory perceptual asymmetries as assessed by DL with children who experience LD are the result of the interaction of hemispheric capability and attention factors.
Coral reef benthic productivity based on optical absorptance and light-use efficiency

In the interest of determining productivity across a range of spatial scales (meters to many kilometers) and in different reef environments, this paper proposes a technique for measuring productivity based on remote sensing of optical absorptance and light-use efficiency. The concept is straightforward: gross primary production equals plant-incident irradiance multiplied by plant absorptance multiplied by the plant’s light-use efficiency (GPP = E d Ae). Both E d and A are derivable from various remote sensing data sources, thus the approach is feasible. This paper presents a demonstration of the application for Kaneohe Bay, Oahu, HI based on Quickbird satellite imagery and SHOALS LIDAR data. E d is modeled at every point in the image, and the image itself is inverted to provide A. Organismal-scale e reported in the literature is taken as a surrogate for community-scale e. The resulting GPP image compares well with the range of GPP values for reef-flats in general, as well as the distribution and range of GPP for Kaneohe Bay in particular. Though results likely can be improved by using spectral imagery and more accurate values for e, this concept study demonstrates the tractability of this approach for measuring coral reef GPP.
A VENTILATING LARYNGOSCOPE FOR INHALATION ANAESTHESIA AND AUGMENTED VENTILATION DURING LARYNGOSCOPIC PROCEDURES

SUMMARY Two versions of a ventilating laryngoscope using principles of fluid amplification are described which provide means of augmented ventilation during laryngoscopic procedures under general anaesthesia and muscle relaxation with unobstructed views of the entire larynx. There is minimal attachment to the laryngoscope; in the simpler Type I venti-laryngoscope, there is only a driving gas line. For delivering inhalation anaesthetics and predetermined gas mixtures, an entrainment arm with reservoir bag is incorporated in the Type II venti-laryngoscope. Intravenous anaesthesia as well as inhalation anaesthesia can be used for laryngoscopy. Clinical experiences and laboratory data provide evidence of adequate ventilation and satisfactory anaesthesia during various laryngoscopic procedures. Flow and pressure measurements have been obtained to facilitate better understanding of the devices.
Trichloroethylene degradation by Escherichia coli containing the cloned Pseudomonas putida F1 toluene dioxygenase genes

Toluene dioxygenase from Pseudomonas putida F1 has been implicated as an enzyme capable of degrading trichloroethylene. This has now been confirmed with Escherichia coli JM109(pDTG601) that contains the structural genes (todC1C2BA) of toluene dioxygenase under the control of the tac promoter. The extent of trichloroethylene degradation by the recombinant organism depended on the cell concentration and the concentration of trichloroethylene. A linear rate of trichloroethylene degradation was observed with the E. coli recombinant strain. In contrast, P. putida F39/D, a mutant strain of P. putida F1 that does not contain cis-toluene dihydrodiol dehydrogenase, showed a much faster initial rate of trichloroethylene degradation which decreased over time.
ALMOST RICCI SOLITONS AND K-CONTACT GEOMETRY

We give a short Lie-derivative theoretic proof of the following recent result of Barros et al. “A compact non-trivial almost Ricci soliton with constant scalar curvature is gradient, and isometric to a Euclidean sphere”. Next, we obtain the result: a complete almost Ricci soliton whose metric \(g\) is \(K\)-contact and flow vector field \(X\) is contact, becomes a Ricci soliton with constant scalar curvature. In particular, for \(X\) strict, \(g\) becomes compact Sasakian Einstein.
Historic climate factors associated with major avalanche years on the Wasatch Plateau, Utah

Abstract This study examined climate factors associated with major avalanche years on the Wasatch Plateau in south-central Utah. Dendro-ecological methods were used to date the occurrence of avalanche events in 16 avalanche paths during the period of 1928–1996. From this information, the probability of avalanche occurrence in each path for each year was calculated, and used to distinguish major avalanche years. The resulting avalanche chronologies indicated that 14 large widespread avalanche events occurred on the Wasatch Plateau between 1928 and 1996. Logistic regression and classification tree analyses were used to examine relationships between climate variables and the probability of major avalanche years. The results of logistic regression analysis showed that mean January snowfall was significantly related (p
Infrared and submillimetre antennas

Abstract The special characteristics of infrared antennas are considered. In particular, we consider the unusual shapes and large dimensions which arise in practical cases, and the desirable planar structure in which an antenna is deposited on a dielectric substrate. Imperfect metallic conduction at high frequencies is also considered. Consequences for design are discussed in a qualitative fashion. Specific cases of interest have been studied by microwave modelling. A promising design for a planar antenna, consisting of a vee antenna with dielectric substrate and superstrate, is developed and studied by microwave simulation. It is found to have a single-lobed pattern well-suited for coupling to a primary mirror, with a gain of about 15 dB.
Some Factors in the Use of High Temperatures in Gas Turbines

A comparison is made between gas-turbine cycles with inlet temperatures of 1,250 and 2,200 deg. F. The use of high inlet temperatures necessitates cooling; the effect of air and water cooling in turbines is examined, and equations are given and used to show the factors controlling cooling loss. A cooling-loss factor is also derived which gives the turbine efficiency obtainable with various degrees of cooling. A cycle with an inlet temperature of 2,200 deg. F. is examined to show the effect of air or water cooling. With water cooling the steam generated is then considered either to provide an increase in useful power or to pre-cool the inlet air. For greater efficiency the steam should be used to increase the power delivered. Practical considerations and a proposed marine layout are given, together with a series of conclusions. Appendices are also included giving the assumptions made and derivations of the equations.
On interface closeness and problem solving

Prior research suggests that "closer" interface styles, such as touch and tangible, would yield poorer performance on problem solving tasks as a result of their more natural interaction style. However, virtually no empirical investigations have been conducted to test this assumption. In this paper we describe an empirical study, comparing three interfaces, varying in closeness (mouse, touchscreen, and tangible) on a novel abstract problem solving task. We found that the tangible interface was significantly slower than both the mouse and touch interfaces. However, the touch and tangible interfaces were significantly more efficient than the mouse interface in problem solving across a number of measures. Overall, we found that the touch interface condition offered the best combination of speed and efficiency; in general, the closer interfaces offer significant benefit over the traditional mouse interface on abstract problem solving.
Neuroactive Steroid Sensitivity in Withdrawal Seizure-Prone and -Resistant Mice

Withdrawal Seizure-Prone (WSP) and -Resistant (WSR) mice, which were selectively bred for severe (WSP) or mild (WSR) handling-induced convulsions (HICs) following chronic ethanol inhalation, were found to differ in sensitivity to the anticonvulsant effects of the neuroactive steroid 3 alpha-hydroxy-5 alpha-pregnan-20-one (3 alpha,5 alpha-P. 3 alpha,5 alpha-P (5 or 10 mg/kg, ip) significantly increased seizure thresholds to pentylenetetrazol in ethanol-native males of both the WSP and WSR lines. In general, WSP mice were more sensitive than WSR mice to the anticonvulsant effect of 3 alpha,5 alpha-P. Subsequent studies in male WSP mice exposed to ethanol vapor or air for 24 hr demonstrated enhanced sensitivity to the anticonvulsant effect of 3 alpha,5 alpha-P (0.5-20 mg/kg, ip) during ethanol withdrawal. Only the highest dose affected HICs in air-exposed animals, whereas both the two highest doses significantly reduced HICs in ethanol-exposed mice. These results provide the first demonstration that 3 alpha,5 alpha-P attenuates ethanol withdrawal convulsions and indicate enhanced sensitivity to the anticonvulsant effect of 3 alpha,5 alpha-P in animals withdrawing from ethanol dependence.
Quantifying Visual Prominence in Social Landscapes

Humans have a cross-cultural tendency to attach strong social meanings to visually prominent landforms. The ability to identify prominent landforms is thus important for understanding how people perceive and relate to a landscape. This is particularly true for historical landscapes, where the relationship between viewer location and view may be one of the few recoverable elements available to reconstruct landscape meaning. Quantifying prominence, however, is a methodological and conceptual challenge, especially if prominence is to be measured from particular ground locations rather than from a planar view. An approach is suggested using a line simplification technique borrowed from cartography that is repurposed to identify prominent points on a horizon line. By combining prominence values with information on the number of viewers present in different vantage points at different points in time, it is possible to reconstruct a visual prominence history for landforms in a region. This approach provides some quantitative rigor to phenomenological approaches that can be overly descriptive and insufficiently transparent. A case study from the American Southwest demonstrates the utility of the method.
High Performing Whipple Patients: Factors Associated with Short Length of Stay after Open Pancreaticoduodenectomy

Despite the decreasing mortality of pancreaticoduodenectomy (PD), it continues to be associated with prolonged length of postoperative hospital stay (LOS). This study aimed to determine factors that could predict short LOS after PD. Additionally, as preliminary data of minimally invasive PD emerges, we sought to determine the average LOS after open PD at a high-volume center to set a standard to which minimally invasive PD can be compared. A total of 634 consecutive patients who underwent open PD between January 2007 and December 2012 at the Massachusetts General Hospital comprised the study cohort. “High performers” were defined as patients with postoperative LOS ≤5 days. Median LOS was 7 days. A total of 61 patients (9.6 %) had LOS ≤5 days and were deemed “high performing.” In multivariate logistic regression analysis, male gender (p = 0.032), neoadjuvant chemoradiation (p = 0.001), epidural success (p = 0.019), epidural duration ≤3 days (p = 0.001), lack of complications (p 5 days, but high performance was predictive of beginning therapy <8 weeks after surgery (p = 0.010). In our experience, median LOS was 7 days, and early discharge (≤5 days) after open PD is safe and feasible in about 10 % of patients. These high performers are more likely to be male, have received neoadjuvant therapy, and had successful epidural analgesia. High performers with cancer are more likely to start chemotherapy <8 weeks after surgery. Minimally invasive PD should be compared to this high standard for median LOS, among other quality metrics, to justify its increased cost, operative duration, and learning curve.
The Dominance of Warming Rate Over Cooling Rate in the Survival of Mouse Oocytes Subjected to a Vitrification Procedure

The formation of more than trace amounts of ice in cells is lethal. The two contrasting routes to avoiding it are slow equilibrium freezing and vitrification. The cryopreservation of mammalian oocytes by either method continues to be difficult, but there seems a slowly emerging consensus that vitrification procedures are somewhat better for mouse and human oocytes. The approach in these latter procedures is to load cells with high concentrations of glass-inducing solutes and cool them at rates high enough to induce the glassy state. Several devices have been developed to achieve very high cooling rates. Our study has been concerned with the relative influences of warming rate and cooling rate on the survival of mouse oocytes subjected to a vitrification procedure. Oocytes suspended in an ethylene glycol-acetamide-Ficoll-sucrose solution were cooled to −196°C at rates ranging from 37°C/min to 1827°C/min between 20°C and −120°C, and for each cooling rate, warmed at rates ranging from 139°C/min to 2950°C/min between −70°C and −35°C. The results are unambiguous. If the samples were warmed at the highest rate, survivals were >80% over cooling rates of 187°C/min to 1827°C/min. If the samples were warmed at the lowest rate, survivals were near 0% regardless of the cooling rate. We interpret the lethality of slow warming to be a consequence of it allowing time for the growth of small intracellular ice crystals by recrystallization.
Ore quality selection and the supply response to nonrenewable resource taxation

This paper examines the effect of taxation on the supply of a nonrenewable resource when ore quality varies within a deposit. The effect of tax policies in this setting can differ from results previously obtained in the literature. For example, if the price path is constant, then a constant royalty can induce a faster rate of depletion, a decrease in the life of the mine, and a reduction in the total recovery of metal from the deposit. The tax increases the metal output in periods when ore extraction is positive.
Cardiopulmonary bypass alters vasomotor regulation of the skeletal muscle microcirculation

Background. Cardiopulmonary bypass (CPB) is associated with alterations in the regulation of organ perfusion and vascular permeability. The purpose of this study was to examine the effects of hypothermic CPB on the regulation of the skeletal muscle microcirculation and the modulating influence of the priming solution. Methods. Sheep were placed on hypothermic CPB with a prime of either Pentastarch hydroxylethyl starch (HS) solution (n = 7), a solution in which HS is conjugated with deferoxamine (n = 7), or Ringer's lactate solution (n = 7). Sheep were placed on hypothermic CPB (27°C) for 90 minutes while the heart was protected with cold blood cardioplegia. Sheep were then separated from CPB and perfused for an additional 3 hours off CPB. Hemodynamics and total water content were measured. Results. In vitro relaxation responses of gracilis muscle arterioles (70 to 180 μm) to the endothelium-dependent agent acetylcholine, the endothelium-independent cyclic GMP-mediated vasodilator sodium nitroprusside, the β-adrenergic agonist isoproterenol, and the adenylate cyclase activator forskolin were studied. No statistically significant hemodynamic differences were observed between groups. However, weight gain was significantly less when the priming solution was HS or HS-deferoxamine compared to when Ringer's lactate was used. Skeletal muscle arteriolar relaxations to the endothelium-dependent vasodilator acetylcholine and the βadrenergic agonist isoproterenol were impaired after CPB in the HS and Ringer's lactate groups. Acetylcholine response was preserved in the HS-deferoxamine group, whereas the response to isoproterenol remained impaired. The responses to sodium nitroprusside and forskolin were similar in all groups. Conclusions. Skeletal muscle microvascular endothelium-dependent relaxation and β-adrenergic relaxation are reduced after CPB using either a crystalloid or HS prime. Skeletal muscle microvascular endothelial dysfunction may be attributable to oxygen-derived free radical-mediated injury, whereas altered β-adrenergic regulation is attributable to mechanisms other than the generation of oxygen-derived free radicals during CPB.
Natural history of allograft coronary arteriopathy: a retrospective study of 54 patients over a 812-year period

A total of 288 patients underwent heart transplantation at Loyola University Medical Center over a 812-year period starting in March, 1984. Of these patients, 54 were identified as having allograft coronary arteriopathy. Diagnosis was made on the basis of abnormal findings on coronary angiography in 44 patients; either an autopsy or explanted heart revealed the diagnosis in the remainder. A total of 279 abnormal lesions were identified by coronary angiography, and over 70% of these stenoses were discrete and located in large epicardial vessels. The left ventricular ed-diastolic pressure demonstrated a steady rise over time (2.5 mmHg/year), and also correlated with the degree of allograft coronary arteriopathy stenosis. The rate of stenosis progression was 33% per year from the time of initial allograft coronary arteriopathy development. Actuarial survival rate was lower than that of patients with arteriopathy. In conclusion, first, the majority of allograft coronary arteriopathy stenoses detected on coronary angiography are discrete, involve large epicardial vessels, and progress rapidly over time. Second, left ventricular end-diastolic pressure seems to reflect the degree of allograft coronary arteriopathy stenosis, and may prove to be a useful indicator of left ventricular dysfunction related to allograft coronary arteriopathy. Third, patients with allograft coronary arteriopathy show a decreased actuarial survival rate.
Telomeric Silencing of an Open Reading Frame in Saccharomyces cerevisiae

The endmost chromosome I ORF is silenced by a natural telomere position effect. YAR073W/IMD1 was found to be transcribed at much higher levels in sir3 mutants and when its adjacent telomere was removed from it. These results suggest that telomeres play a role in silencing actual genes.
Enhanced Release of Drugs from Silicone Elastomers (III): Subcutaneous Controlled Administration of Melatonin for Early Onset of Estrus Cycles in Ewes

AbstractImplants were fabricated from swellable silicone elastomers to release hydrophilic melatonin at a controlled rate for the early induction of breeding season in ewes. Both the in vitro and in vitro release profiles of melatonin were observed to follow a linear Q vs. t1/2 relationship. The in vitro/in vivo release flux ratio ranging from 0.415 to 1.452 was obtained depending upon the polyethylene glycol 400 concentration in the aqueous release medium used for in vitro studies. The release flux (Q/t1/2) of melatonin from the implants was observed to increase as a function of the glycerol content in the silicone elastomers. When the ewes were treated with subdermal implants containing 25% w/w of melatonin for up to 49 days, blood melatonin levels above the target level of 450-900 pmole/1 were achieved and maintained for at least 35 days.
Effects of adaptive robot dialogue on information exchange and social relations

Human-robot interaction could be improved by designing robots that engage in adaptive dialogue with users. An adaptive robot could estimate the information needs of individuals and change its dialogue to suit these needs. We test the value of adaptive robot dialogue by experimentally comparing the effects of adaptation versus no adaptation on information exchange and social relations. In Experiment 1, a robot chef adapted to novices by providing detailed explanations of cooking tools; doing so improved information exchange for novice participants but did not influence experts. Experiment 2 added incentives for speed and accuracy and replicated the results from Experiment 1 with respect to information exchange. When the robot's dialogue was adapted for expert knowledge (names of tools rather than explanations), expert participants found the robot to be more effective, more authoritative, and less patronizing. This work suggests adaptation in human-robot interaction has consequences for both task performance and social cohesion. It also suggests that people may be more sensitive to social relations with robots when under task or time pressure.
Observations of Representational Practices by Indian-Descent Children in a US Preschool Classroom: Connections Among People, Spaces and Artifacts

This exploratory study examined children’s experiences with producing and comprehending external representations in a preschool classroom. Data collection and analyses focused on how artifacts, spaces, adult-guided routines, and social conventions shape young children’s representational development. Participants included 4- and 5-year-old preschoolers of East Indian-descent, a head classroom teacher of European descent, and other adult assistants. Analyses revealed variations in adult mediation and child participation across types of representational practices (reading, drawing, pretending, etc.). Furthermore, there were numerous relationships among artifacts, practices and spaces within the classroom which varied across practices. These findings may help educators, parents and psychologists better understand how young children become competent members of representation-using communities.
Gendered Self-Fashioning: Adelaide Casely Hayford's Black Atlantic

times of Africans who were subject to colonialism. This interest has not only been spawned by a desire to outline a deeper literary history of the African continent than has often been assumed by its academic "postcolonialist" consumers, but it has also arisen out of a genuine concern for the ways in which Africa and African agency, in particular, have been represented in the colonial and indeed, often, the postcolonial archive. So, for instance, the lay version of the story of African literary production would continue to see the beginnings of a written literary tradition in Africa with the publication of Achebe's Things Fall Apart or, at best, in the earlier writings of Amos Tutuola and his Palm Wine Drinkard. Everything before this, so the story assumes, was "oral tradition." To be sure, this version of the story has never been the official story of the discipline, but it continues to be part not only of the popular consciousness but also often of the professional unconscious. And it is for this reason that titles of scholarly articles, such as Albert Gerard's "1500 Years of Creative Writing in Black Africa" published in Research in African Literatures in 1981, still come across as a little provocative, a little jarring. In that article, Gerard states categorically, "In historical fact, important segments of subsaharan Africa had been introduced to writing and to written literature long before the first white man-whether explorer or philanthropist-reached her shores" (147). He continues to outline the growth of a written African literary tradition in the Ge'ez language of Ethiopia, in the Arabic of the East African coast, and in eighteenth-century Swahili. Before concluding with the generation of postcolonial writers with whom we are most familiar, he pays significant attention to the nineteenthand twentieth-century development of missionary presses in colonial Africa. These presses, primarily interested in producing translations of the Bible in the indigenous languages of Africa, found it necessary at first to develop an orthography
How super-renormalizable interactions cure their infrared divergences

Perturbative expansions in models which possess super-renormalizable interactions of massless fields are beset by severe infrared divergences. We show that the complete theory is well defined and has no such divergences; rather the exact amplitudes are nonanalytic functions of the coupling constant and cannot be expanded in its powers. Typically, logarithms of the coupling constant occur, as well as analytic pieces. The analytic portions cannot be found in perturbation theory; they are determined by matrix elements of composite operators. But the nonanalytic behavior is completely fixed in terms of the theory's other parameters. The present investigation should be relevant to a study of physical quantum chromodynamics at its finite-temperature phase transitions.
EVANESCENT MODES AND SCATTERING EFFECTS ON RESONANT TUNNELING IN ZERO DIMENSIONAL NANOSTRUCTURES: A SCATTERING MATRIX APPROACH

Theoretical calculations of tunneling characteristics of the Gated Resonant Tunneling Diode (GRTD) aie obtained in low dimensionality using a scattering transfer matrix approach. In the bias conditions whereby the GRTD reaches zero‐dimension in the well region, we consider attractive and repulsive perturbation potential (Vsc) of impurity or defect scattering in emitter and well regions. We describe the scattering matrices using the presence of evanescent, or nonpropagating, modes in different lateral confinement structure. Numerical solutions to the two‐dimensional Poisson equation and the continuity equation are used to calculate the lateral depletion region and carrier concentrations by the finite difference method. Electron transport in double‐barrier structure is calculated by a self‐consistent approach.
Some observations on the determination of phenol using ion selective electrodes

Abstract A PVC phenoxyacetate selective electrode has been developed for the indirect sensing of phenol, after in situ derivatization with chloroacetic acid. The electrode exhibits a Nernst response in the range 10−1 − 3.2 × 10−4 M phenoxyacetate with a slope of 68.9 mV per concentration decade. The electrode has a wide working pH range (7.5–11.0), a fast response time (less than l min), and is stable for at least 1 1 2 months.
Initial experience with a CCD-based imaging system

A prototype imaging system for digital x-ray imaging of the chest is under development in our research laboratory. The image receptor consists of a 40/30/22-cm image intensifier and an electronic camera employing a 1320 x 1035-pixel scientific grade CCD. The veiling glare-to-primary ratio and spatial resolution have been measured.
Hydrogen generation from ammonia borane and water through the combustion reactions with mechanically alloyed Al/Mg powder

Abstract : Finding and developing a safe and effective method for hydrogen storage is integral to its use as an alternative source of energy. The goal of the studies described in this thesis was to investigate the feasibility of developing combustible hydrogen-generating compositions based on ammonia borane and novel energetic materials such as nanocomposite and mechanically alloyed reactive materials, recently obtained by Prof. Edward Dreizin's team at the New Jersey Institute of Technology (NJIT). Such compositions could be stored for long time and release hydrogen on demand, upon ignition. The first phase of the research included thermodynamic calculations for combustion of ammonia borane with various reactive materials obtained at NJIT. The second phase involved experiments with compositions that appeared to be promising based on thermodynamic calculations. An experimental setup with laser ignition of mixtures was developed for these experiments. As a result of these tests, further work was focused on mixtures of ammonia borane, gelled water, and mechanically alloyed Al/Mg powder. The last part of the research revealed the reaction mechanisms during combustion of these mixtures. For this purpose, isotopic tests, involving use of heavy water and mass-spectroscopy of gaseous combustion products, were conducted. The results of the present work indicate that combustible mixtures of ammonia borane, water, and mechanically alloyed Al/Mg powder are promising for the development of hydrogen generators that release large amounts of hydrogen upon ignition.
Camera-based digital real-time static and dynamic testing of deployable/inflatable structures

NASA's recent space programs require the use of many ultra-lightweight deployable/inflatable structures, but there are many modeling, analysis and testing problems. A total-Lagrangian finite element code GESA (Geometrically Exact Structural Analysis) is being developed by the authors by implementing geometrically exact structural theories for the modeling, analysis, and fast prototyping of Highly Flexible Structures (HFSs). However, it is very challenging to experimentally verify the large static and dynamic deformations of such lightweight HFSs by using conventional sensors. This paper presents the use of an EAGLE-500 real-time motion analysis system to measure large static and dynamic deformations of HFSs in order to verify the accuracy of numerical solutions obtained from GESA. Experimental results obtained from several highly flexible structures are used to show the capabilities of this system in characterizing nonlinear statics and dynamics of HFSs.
Clinical Applications of DAT using a QWIP FPA camera

Dynamic area telethermometry (DAT) is a new approach for the use of IR imaging in medicine. DAT allows rapid, non-contact assessment of cutaneous perfusion and study of the dynamics of subcutaneous blood flow. Consequently, DAT can be a useful tool in the management of vascular and plastic surgeries, as well as in the diagnosis of neuronal disorders that affect the vasculature. DAT can also be very useful in the diagnosis and management of non-neuronal disorders, such as cancer, associated with abnormal dynamics of local perfusion. The application of DAT in the diagnosis of breast cancer is described as a model for converting a qualitative subjective imaging technique into a quantitative objective test.
The azimuthal variation of teleseismic P-wave residuals for stations in southern California

Abstract A study of teleseismic P-residuals for 13 stations in southern California reveals that these vary systematically with the azimuth of the event; the residuals generally tend to be negative in the NW and SE quadrants. This effect is greatest in the north of the region: a maximum peak-to-peak variation of 1.3 sec with residuals as low as −0.9 sec was observed at Isabella. The delays become less negative further south in the region, and at the southernmost station, Glamis, delays of up to +0.75 sec were observed to the west. The latter may be associated with velocity decreases in the active geothermal areas of the Imperial Valley. A simple model, consisting of a region some 175 km wide and 100 km thick at a depth of approximately 100 km in which a velocity increase of up to 0.45 km/sec occurs, is proposed to account for the observed variations. This region trends NW-SE approximately parallel to the North America-Pacific plate boundary. The proposed velocity changes are consistent with a pinching out of the low-velocity (partial melting) zone under the area, such as has been proposed to explain the low heat flow in the Sierra Nevada, and may be related to the presence of an ancient (∼ 30 m.y.) subduction zone under southern California.
Novel Kv3 glycoforms differentially expressed in adult mammalian brain contain sialylated N-glycans.

The N-glycan pool of mammalian brain contains remarkably high levels of sialylated N-glycans. This study provides the first evidence that voltage-gated K+ channels Kv3.1, Kv3.3, and Kv3.4, possess ...
Influence of humoral shock factors on in vitro aggregation of dog platelets.

Abstract We studied the effect of humoral factors present during shock on platelet aggregation. At plasma concentrations present in shock, prostaglandin E1 significantly inhibited ADP induced aggregation of dog platelets. Prostaglandins E2, F2α, and D2 at shock concentrations exerted no significant effect on ADP induced aggregation. PGE2 inhibited only the first phase of aggregation at a concentration which was much higher than that present in shock. Although arachidonic acid is a potent aggregation inducing agent in certain species, its effect on dog platelets is only very slight. Purified preparations of cathepsin B1 and C and a myocardial depressant factor (MDF) did not induce dog platelet aggregation nor did MDF or cathepsin B1 modify ADP induced aggregation. Although cathepsin C inhibited ADP induced aggregation, this effect was independent of its proteolytic activity. Thus, humoral factors released in shock do not appear to accentuate tissue hypoperfusion by inducing or modifying platelet aggregation.
A terrain-dependent reference atmosphere determination method for available potential energy calculations

An iterative technique that determines the reference atmosphere which incorporates the effects of uneven surface topography is presented. This method has been successfully applied in several available potential energy studies. An alternative method due to Taylor is also evaluated. While Taylor presented excellent continuous formulations of the available potential energy that include topography, his method for determining the reference atmosphere distributions failed to provide the accuracy needed to produce reliable available potential energy estimates. Since topography has a significant influence on the general circulation, it is important to employ techniques that incorporate its effects in the determination of available potential energy.
Spinning mode sound propagation in ducts with acoustic treatment and sheared flow

The propagation of spinning mode sound was considered for a cylindrical duct with sheared steady flow. Calculations concentrated on the determination of the wall optimum acoustic impedance and the maximum possible attenuation. Both the least attenuated and higher radial modes for spinning lobe patterns were considered. A parametric study was conducted over a wide range of Mach numbers, spinning lobe numbers, sound frequency, and boundary layer thickness. A correlation equation was developed from theoretical considerations starting with the thin boundary layer approximation of Eversman. This correlation agrees well with the more exact calculations for inlets and provides a single boundary layer refraction parameter which determines the change in optimum wall impedance due to refraction effects.
The pathogenesis of cholesterol gallstones—A review

Abstract Cholesterol is extremely insoluble in water. As a result, cholesterol secretion into bile is highly regulated and once secreted into bile, solubility is maintained by cholesterol transporters. Understanding the physicochemical relationships between cholesterol and its transporters is key to understanding gallstone formation. Stone formation requires excess cholesterol secretion into bile, which produces cholesterol supersaturation. Many of the epidemiologic risk factors for stone formation such as obesity, femaleness, and age can now be linked to specific abnormalities of cholesterol metabolism. Cholesterol supersaturation is necessary but not sufficient for cholesterol crystal formation. Crystallization also requires a gallbladder motility defect and/or the presence of procrystallizing factors such as mucous glycoprotein or immunoglobulins. The latter seem to be stimulated by gallbladder inflammation. Stone growth is the final step in stone formation and the least well understood. Recent work suggests that cholesterol stones form as agglomerations of cholesterol crystals and that pigmentation is secondary.
Continued expression of neonatal myosin heavy chain in adult dystrophic skeletal muscle

The expression of myosin heavy chain isoforms was examined in normal and dystrophic chicken muscle with a monoclonal antibody specific for neonatal myosin. Adult dystrophic muscle continued to contain neonatal myosin long after it disappeared from adult normal muscle. A new technique involving western blotting and peptide mapping demonstrated that the immunoreactive myosin in adult dystrophic muscle was identical to that found in neonatal normal muscle. Immunocytochemistry revealed that all fibers in the dystrophic muscle failed to repress neonatal myosin heavy chain. These studies suggest that muscular dystrophy inhibits the myosin gene switching that normally occurs during muscle maturation.
The tuberoinfundibular system of the rat as demonstrated by immunohistochemical localization of retrogradely transported wheat germ agglutinin (WGA) from the median eminence.

Abstract The origin of neuronal perikarya which project to the external zone of the median eminence (the tuberoinfundibular neuronal system) was determined in the rat after injection or diffusion of wheat germ agglutinin (WGA) into the median eminence. The retrogradely transported lectin was detected in neurons using an immunohistochemical method based on the peroxidase-antiperoxidase technique. Immunoreactive cell bodies were found both in hypothalamic and extrahypothalamic regions. Within the hypothalamus, the majority of peroxidase-positive cells were present in the dorsomedial and basolateral portions of the arcuate nucleus, regions of the periventricular nucleus, and the preoptic region, particularly at the level of the organum vasculosum of the lamina terminalis (OVLT). Within the extrahypothalamic regions. WGA-positive perikarya were found in the diagonal band of Broca, the region of the medial septum and the brainstem. Only rare cells were labeled in the ventromedial nucleus of the hypothalamus and no cells were labeled in any region of the amygdala. These data demonstrate that neurons with afferent projections to the median eminence are more widely distributed in the rat brain than previously recognized and therefore, that the concept of the tuberoinfundibular neuronal system must be expanded.
The nature of surgical error: a cautionary tale and a call to reason.

Errors and “patient safety” have taken on monumental importance for surgery. Like all things new, there is an initial over-reaction before a return to a balanced perspective. The current response to the global interest in error has been to seize on the latest reports that are focusing on the “systemic nature” of errors, which is also being referred to as “the new look.” There has been an unintentional ignoring of the actual error, referred to as the coface error, that the surgeon commits. It is time to put the approach to errors into perspective and redefine errors within the context of the surgical community, which can result in a balance of the surgeon’s position in regard to systemic and personal responsibility.
Enhancement of melphalan cytotoxicity in vivo and in vitro by inhibitors of poly (ADP-ribose) polymerase

Abstract In these preliminary experiments, we have found enhanced cell killing by the bifunctional alkylating agent L-phenylalanine mustard (L-PAM) in the presence of inhibitors of poly (ADP-ribose) polymerase (ADPRP) in vitro . In vivo enhancement of the tumoricidal effects of L-PAM was observed with the ADPRP inhibitor nicotinamide (1000 mg/kg), although enhanced myelosuppression was also demonstrated. Nicotinamide also increased the plasma elimination half-life of L-PAM by a factor of at least 2. This alteration of L-PAM pharmacokinetics makes it difficult to assess the role that ADPRP inhibition plays in the enhancement of L-PAM tumor cell killing in vivo .
Studies on neurotrophic and substrate — attached neurite outgrowth factors

STUDIES ON NEUROTROPHIC AND SUBSTRATE - ATTACHED NEURITE OUTGROWTH FACTORS Reichardt, L.F . , Calof, A.L., Gorin, P .D., Greenspan, R.J., Greif, K. F., 1,ander, A.D. Matthew, W.D., Shelton, D.L., Tomaselli, K., & Winter, J. Dept. Physiology, UCSF, San Francisco, CA 94143 Neurons require appropriate substrata on vhich to extend neurltes and the composltion of the substrata encountered in vivo is believed to regulate both. the extent and directlon of axon growth as well as t he position at which synaptic speciallzations appear. In particular, three constituents of extracellular matrix--fib r onectin, laminin, and factors associated with heparan sulfate proteo- glycans--have dr amatic effects on neurite outgrowth in appropriate circumstances. Several of these factors have been shown to exist in appropriate positions to promote neurite growth in vivo as well as in vitro. The response of neurons to such factors depends on-Cheir growth state-.- This presentation will focus on characterization of these neurite outgrowth promoting factors and our efforts to determine their roles in directing neuronal development. The role of ECM compo- nents in directing axon growth and guidance in vivo is poorly understood . The Study of soluble factors, which conta1.n ECM components and act when bound to a substratum, may offer insights into that role. Supported by gi:-;rnts from the Niil, NSF, March of Dimes, and MDA.
NMR Structures of (rGCUGAGGCU)(2) and (rGCGGAUGCU)(2): Probing the Structural Features That Shape the Thermodynamic Stability of GA Pairs(,).

The NMR structures of and are reported. The internal loop, , is about 2 kcal/mol more stable than at 37 °C. The duplexes assemble into similar global folds characterized by the formation of tandem sheared GA pairs. The different stabilities of the loops are accompained by differences in the local structure of the closing GU pairs. In the internal loop, the GU pairs form canonical wobble configurations with two hydrogen bonds, whereas in , the GU pairs form a single hydrogen bond involving the amino group, GH22, and the carbonyl group, UO4. This pairing is similar to the GU closing pair of the 690 hairpin loop found in E. coli 16S rRNA. The and structures reveal how the subtle interplay between stacking and hydrogen bonding determines sequence dependent conformation and thermodynamic stability. Thus, this work provides structural and thermodynamic benchmarks for theoreticians in the ongoing effort to understand the sequence dependence of RNA physicochemical properties.