cssi/SciSciGPT-SciSciNet huggingface dataset:
Oat phyA containing transgenic tobacco: an examination of oat phyA mRNA stability and the role of oat phyA in germination of tobacco seed

The regulation of oat phytochrome A {phyA) mRNA stability and the photoregulation of germination of tobacco seeds containing the oat phyP^ gene was examined using oat phyA. containing transgenic tobacco. Oat phyk mRNA has been previously shown to be a relatively unstable mRNA. The intent of this research was to identify elements within the phyK mRNA responsible for rendering the message unstable. The approach taken was to use tobacco transformed with either the full-length or truncated versions of the oat phyK gene and examine the half-lives of the resulting oat phyK mRNAs in transgenic tobacco. RNA blot analysis of oat phyh. in both oats and in tobacco transformed with the oat phyA. gene showed a pattern of oat phyK hybridizable fragments smaller than the full-length mRNA band. These fragments were thought to be degradation products indicative of a short-lived message. The half-lives of the truncated oat phyk mRNAs were found to be between 90 minutes and four hours. The full-length oat phyk mRNA had a half-life of about four hours in transgenic tobacco. Determination of the half-life of both truncated and fiill-length oat phyk mRNAs in transgenic tobacco suggests that the amount of oat phyk hybridizable fragments does not correlate with mRNA half-life. Germination of seeds from wild-type tobacco plants requires light. Approximately 20% of the seeds from transgenic tobacco plants containing the oat phyk gene and grown under fluorescent lighting were found to germinate in the dark. Seeds from transgenic tobacco grown under fluorescent and incandescent lighting did not germinate in darkness. A higher percentage of seeds from both wild-type and transgenic plants were found to germinate when imbibed in the presence of nitrate. About 50% of the seeds from transgenic plants grown in the presence of incandescent lighting and imbibed in the presence of nitrate germinated in darkness. The higher level of phytochrome in the transgenic seedlings promoted germination and was sensitive to the light conditions under which the parent plants were grown. These findings suggest that phyk plays a role in promoting germination in tobacco seeds.
Clonal analysis of the in vivo differentiation potential of keratinocytes

Purpose. This study investigated the in vivo differentiation of conjunctival keratinocytes. Methods. Keratinocytes from the fornical region of the conjungtival epithelium were isolated and plated at low density (5 X 102 per 100-mm dish) in Dulbecco's minimum essential medium containing 20% fetal bovine serum in the presence of mitomycin C-treated 3T3 feeder cells. At this density, only single, isolated cells were attached after overnight culture. Eight days later, small, well-isolated colonies separated from one another by the feeder cells were detached as a sheet from the dish and were injected subcutaneously into the flanks of BALB/c athyinic mice through an 18-gauge needle. Within a day, a small firm nodule appeared at the site of injection. At different time points, the animals were killed, and the nodules were excised for morphologic, histogeometrie, and cell kinetic analyses. Results. Each implanted colony derived from a single cell gave rise to a single epithelial cyst lined with a reconstituted stratified epithelium. Goblet-like cells loaded with periodic acid-Schiff-positive cytoplasmic granules began to appear singularly in some of the cysts by day 8 postimplantation and were observed in approximately 85% of the cysts by day 14. Conclusions. Because the cysts formed were derived from clonal populations of epithelial cells and the majority of cysts had a mixed keratinocyte-goblet cell phenotype, these results suggest strongly the existence of a bipotent precursor cell in conjunctival epithelium that can give rise to both goblet and nongoblet cells. This system can be used to study factors that can influence the commitment of pluripotent epithelial stem cells to divergent pathways of differentiation.
Dispersal success on fractal landscapes: a consequence of lacunarity thresholds

Habitat fragmentation is expected to disrupt dispersal, and thus we explored how patch metrics of landscape structure, such as percolation thresholds used to define landscape connectivity, corresponded with dispersal success on neutral landscapes. We simulated dispersal as either a purely random process (random direction and random step lengths) or as an area-limited random walk (random direction, but movement limited to an adjacent cell at each dispersal step) and quantified dispersal success for 1000 individuals on random and fractal landscape maps across a range of habitat abundance and fragmentation. Dispersal success increased with the number of cells a disperser could search (m), but poor dispersers (m<5) searching via area-limited dispersal on fractal landscapes were more successful at locating suitable habitat than random dispersers on either random or fractal landscapes. Dispersal success was enhanced on fractal landscapes relative to random ones because of the greater spatial contagion of habitat. Dispersal success decreased proportionate to habitat loss for poor dispersers (m=1) on random landscapes, but exhibited an abrupt threshold at low levels of habitat abundance (p<0.1) for area-limited dispersers (m<10) on fractal landscapes. Conventional metrics of patch structure, including percolation, did not exhibit threshold behavior in the region of the dispersal threshold. A lacunarity analysis of the gap structure of landscape patterns, however, revealed a strong threshold in the variability of gap sizes at low levels of habitat abundance (p<0.1) in fractal landscapes, the same region in which abrupt declines in dispersal success were observed. The interpatch distances or gaps across which dispersers must move in search of suitable habitat should influence dispersal success, and our results suggest that there is a critical gap-size structure to fractal landscapes that interferes with the ability of dispersers to locate suitable habitat when habitat is rare. We suggest that the gap structure of landscapes is a more important determinant of dispersal than patch structure, although both are ultimately required to predict the ecological consequences of habitat fragmentation.
A Study of Bus High-Resolution GPS Speed Data Accuracy:

The recent availability of high-frequency transit (HFT) GPS data for buses has allowed the estimation of detailed bus-travel speed profiles between bus stops. HFT data are defined as data comprisin...
Intraventricular hemorrhage following removal of external ventricular drains: Report of 2 pediatric cases

Abstract Risk of intraventricular bleeding following External Ventricular Drains (EVDs) placement is well recognized. On the contrary, hemorrhage following removal of EVD is considered highly unlikely. We report two cases of massive, symptomatic intraventricular hemorrhage that occurred soon after removal of EVD, in two pediatric patients, one affected by posterior fossa tumor, and the other by acute post-traumatic hydrocephalus. This complication significantly affected outcome: in both cases EVD should be replaced, hospitalization was prolonged and further surgery was required for persisting hydrocephalus. The first patient also presented neurological deficits and delay in starting oncological therapies. There are currently no articles that specifically address hemorrhagic risk in EVDs removal. Only one paper that evaluates EVD associated hemorrhage also discuss about hemorrhages caused by removal of the catheter in children. Such risk appears to be not negligible, with hemorrhagic rate of 21.9%. More often, these hemorrhages have few clinical significance, but severe sequelae, may also occur. This should be considered in decision making, and in discussing the risks with a patient's family.
Use of Recommended Preventive Health Care Services and Variations in HIV Care Among Women With HIV in the United States, 2013-2014: Opportunities for Expanded Partnerships in Support of Ending the HIV Epidemic.

BACKGROUND Despite recommendations for preventive health services and routine HIV care for HIV-positive women, limited data are available regarding uptake of recommendations. METHODS We used data from the 2013-2014 data cycles of the Medical Monitoring Project. We calculated weighted estimates and used multivariable logistic regression with adjusted prevalence ratios and 95% confidence intervals to examine associations between preventive health screenings, routine HIV care [based on viral load (VL) and CD4 measures as proxies], and sociodemographic factors. RESULTS Of 2766 women, 47.7% were 50 years and older, 61.7% non-Hispanic black, 37.2% had >high school education, 63.3% had been living with HIV for ≥10 years, 68.4% were living ≤the federal poverty level, 67.3% had public health insurance, 93.8% were prescribed antiretroviral therapy, and 66.1% had sustained/durable suppression (12 months). For women aged 18 years and older, cervical cancer, breast cancer, and sexually transmitted infection screenings were documented for 44.3%, 27.6%, and 34.7%, respectively; 26% did not meet 6-month, and 37% did not meet 12-month, VL and CD4 test measure goals. In multivariable analyses, women with no VLs in the past 6 months were less likely to be durably suppressed, and women who did not have ≥3 CD4 or VL tests (past 12 months) were less likely to be living above the poverty level and more likely to have public insurance compared with private health insurance (P < 0.05). CONCLUSION Receipt of recommended preventive care was suboptimal. Targeted interventions are warranted to help ensure access to comprehensive HIV care and prevention services for women.
The effects of concentrated eluted anti-red blood cell antibodies on the in vivo survival of normal red blood cells.

1. A method has been described for the preparation and sterilization of a concentrated eluate from human red cell stroma. 2. Red cells sensitized by such an eluate prepared from normal control red cells showed entirely normal in vivo survival, as did cells sensitized by eluate from anti-H coated cells. 3. Sensitization of red cells by concentrated eluates from a patient with Coombs-negative acquired hemolytic anemia and from a patient with Coombs-positive acquired hemolytic anemia did not cause significant alteration in the in vivo survival of the red cells. 4. Red cells sensitized by the concentrated eluate from anti-D sensitized cells disappeared from the recipient’s circulation very rapidly and were sequestered in the spleen, indicating preservation of the physiologic properties of the antibody throughout the elution, concentration and sterilization procedures.
Blood Flow through Arteriovenous Anastomoses

Arteriovenous anastomoses or communications between arteries and veins larger in calibre than capillaries have been reported by anatomists in a number of tissues [1]. Their function has been observed by microscopic observations of the microcirculation of living tissues [2]. In order to evaluate the physiological significance of this phenomenon on the overall circulatory system, it has been necessary to estimate the relative magnitude of blood flow through these anas-tomoses compared to flow through the capillaries. This has been accomplished with arterial injections of particles. When particles too large to pass through capillaries are injected into an artery, only the particles carried by the blood flowing through the anastomoses will pass to the venous side of the circulation. Thus, the fraction of injected particles flowing out of the perfused tissues estimates shunting, or the relative blood flow through the anastomoses. Using this principle, significant shunt blood flow was demonstrated in the hindlegs of anesthetized dogs fifteen years ago by Piiper and Schoedel [3]. Recently we repeated and verified the results of these earlier investigators [4] using a new technique developed by the author. In this method, 99mTc-labeled serum albumin microspheres are injected into an artery and the shunted microspheres detected by external radiation counting after they are trapped in the lungs. As in the previous study, we found that a significant and variable fraction of extremity blood flow was shunted. With this new technique, however, it has been possible to make the measurements without interfering with the normal circulation and the measurements can be made repeatedly in the same subject. This allows one to study changes in shunting in response to the various parameters of blood flow. Because the particles are made from human serum albumin the method is applicable to man as well as experimental animals.
Bus Snubber Optimization for Multi-Chip Power Modules using SPICE Simulations

Bus snubbers are a commonly used mechanism for improving the switching performance of circuits using wide bandgap devices. Particularly, their influence on switching losses and transient overshoot is of interest. However, bus snubbers can have multiple effects on these behaviors, resulting in a series of tradeoffs. Understanding the tradeoffs associated with bus snubber design can assist in selecting an optimal value for a given system, but determining this optimal value empirically is challenging and time consuming. As such, this paper leverages a SPICE simulation model of a multi-chip power module and accompanying application circuit to analyze these trends. This simulation model is empirically validated with a set of experiments performed on a double pulse test stand. The resulting analysis demonstrates that the presented SPICE model can facilitate the selection of an optimal bus capacitor, thereby reducing the need for empirical analysis. The effect of additional resistance in the snubber circuit is also analyzed empirically, revealing further tradeoffs to be considered for snubber design.
Chemoprevention of Colorectal Cancer

Although colorectal cancer (CRC) screening has reduced the incidence of and mortality from CRC, chemoprevention strategies have the potential to further reduce CRC incidence and mortality. Chemoprevention agents might be used for average-risk as well as high-risk groups, and to prevent CRC recurrence after therapy. CRC chemoprevention agents that have been studied include aspirin, nonaspirin nonsteroidal anti-inflammatory drugs, statins, agents that target metabolic pathways, and vitamins and minerals. We review the prospect of chemoprevention of CRC, results from preclinical and human studies, challenges, and future directions.
China y la gobernanza económica global

A lo largo de la ultima decada, China ha asumido un creciente protagonismo con respecto a la reforma de las estructuras de la gobernanza global. Su discurso e iniciativas revelan su preferencia por un orden que reconozca un mayor peso a los paises en desarrollo frente a Occidente, pero que al mismo tiempo resulte favorable a sus especificos intereses nacionales. Las dimensiones adquiridas por la economia china y las cada vez mas explicitas ambiciones internacionales de sus dirigentes obligan a preguntarse por sus intenciones y agenda, asi como por el impacto de la transformacion que pretende. Aunque no resulta plausible que China suceda a Estados Unidos al frente del sistema multilateral, si puede emerger un nuevo orden hibrido o pluralista.
Expert-level detection of acute intracranial hemorrhage on head computed tomography using deep learning.

Computed tomography (CT) of the head is used worldwide to diagnose neurologic emergencies. However, expertise is required to interpret these scans, and even highly trained experts may miss subtle life-threatening findings. For head CT, a unique challenge is to identify, with perfect or near-perfect sensitivity and very high specificity, often small subtle abnormalities on a multislice cross-sectional (three-dimensional [3D]) imaging modality that is characterized by poor soft tissue contrast, low signal-to-noise using current low radiation-dose protocols, and a high incidence of artifacts. We trained a fully convolutional neural network with 4,396 head CT scans performed at the University of California at San Francisco and affiliated hospitals and compared the algorithm’s performance to that of 4 American Board of Radiology (ABR) certified radiologists on an independent test set of 200 randomly selected head CT scans. Our algorithm demonstrated the highest accuracy to date for this clinical application, with a receiver operating characteristic (ROC) area under the curve (AUC) of 0.991 ± 0.006 for identification of examinations positive for acute intracranial hemorrhage, and also exceeded the performance of 2 of 4 radiologists. We demonstrate an end-to-end network that performs joint classification and segmentation with examination-level classification comparable to experts, in addition to robust localization of abnormalities, including some that are missed by radiologists, both of which are critically important elements for this application.
A Phase 3 Trial of Difelikefalin in Hemodialysis Patients with Pruritus

Abstract Background Difelikefalin is a peripherally restricted and selective agonist of kappa opioid receptors that are considered to be important in modulating pruritus in conditions such as chron...
Youths' processing of emotion information: Responses to chronic and video-based laboratory stress.

Abstract Integrating multiple sources of information about others’ emotional states is critical to making accurate emotional inferences. There is evidence that both acute and chronic stress influence how individuals perceive emotional information. However, there is little research examining how acute and chronic stress interact to impact these processes. The current study examined whether acute and chronic stress interact to influence how children make emotional inferences. Eighty-nine youths (aged 11–15 years) underwent a novel video-based social stressor. Children completed an emotion recognition task prior to and after the stressor in which they saw integrated displays of facial expressions and contexts depicting congruent or incongruent emotional information. Eye tracking assessed changes in attention to the stimuli. Children became more likely to use and attended more to facial information than contextual information when labeling emotions following exposure to acute stress. Moreover, the effect of acute stress on use of facial information to label emotions was stronger for children who experienced higher levels of chronic stress. These data suggest that acute stress shifts attention towards facial information while suppressing processing of other sources of emotional information, and that youths with a history of chronic stress are more susceptible to these effects.
Prediction of aerodynamic flow fields using convolutional neural networks

An approximation model based on convolutional neural networks (CNNs) is proposed for flow field predictions. The CNN is used to predict the velocity and pressure field in unseen flow conditions and geometries given the pixelated shape of the object. In particular, we consider Reynolds Averaged Navier–Stokes (RANS) flow solutions over airfoil shapes as training data. The CNN can automatically detect essential features with minimal human supervision and is shown to effectively estimate the velocity and pressure field orders of magnitude faster than the RANS solver, making it possible to study the impact of the airfoil shape and operating conditions on the aerodynamic forces and the flow field in near-real time. The use of specific convolution operations, parameter sharing, and gradient sharpening are shown to enhance the predictive capabilities of the CNN. We explore the network architecture and its effectiveness in predicting the flow field for different airfoil shapes, angles of attack, and Reynolds numbers.
Reducing Benzodiazepine Exposure by Instituting a Guideline for Dexmedetomidine Usage in the NICU.

BACKGROUND Midazolam is a benzodiazepine sedative used in NICUs. Because benzodiazepine’s effects include respiratory depression and potential detrimental developmental effects, minimizing exposure could benefit neonates. Dexmedetomidine is routinely used for sedation in older pediatric populations. We implemented a quality improvement initiative with the aim of decreasing midazolam infusions by 20% through use of dexmedetomidine. METHODS A multidisciplinary committee created a sedation guideline that included standardized dexmedetomidine dosing escalation and weaning. Baseline data collection occurred from January 2015 to February 2018, with intervention from March 2018 to December 2019. Percentage of sedation episodes with dexmedetomidine initiated was followed as a process measure. Outcomes measures were percentage of eligible infants receiving midazolam infusions and midazolam-free days per sedation episode. Bradycardia with dexmedetomidine, unplanned extubation rates, and morphine dosage were monitored as balancing measures. RESULTS Our study included 434 episodes of sedation in 386 patients. Dexmedetomidine initiation increased from 18% to 49%. The intervention was associated with a significant reduction in midazolam initiation by 30%, from 95% to 65%, with special cause variation on statistical process control chart analysis. Midazolam-free days per sedation episode increased from 0.3 to 2.2 days, and patients receiving dexmedetomidine had lower midazolam doses (1.3 mg/kg per day versus 2.2 mg/kg per day, P = 5.97 × 10−04). Bradycardia requiring discontinuation of dexmedetomidine, unplanned extubation rates, and morphine doses were unchanged. CONCLUSIONS Implementation of a quality improvement initiative was successful in reducing the percentage of patients receiving midazolam infusions and increased midazolam-free days per sedation episode, revealing an overall reduction in benzodiazepine exposure while maintaining adequate sedation.
Science-based regulatory considerations for regenerative medicine cellular products

Abstract Regenerative medicine is a rapidly expanding field given its potential to treat highly complex health conditions and rare diseases. However, the application of the US Food and Drug Administration (FDA) regulatory framework to these innovative products can be challenging given their highly variable and complex nature. Nevertheless, the rapid development of cellular products and their fast-paced innovation requires FDA to develop new tools, standards, and approaches with which to adequately assess their safety, efficacy, quality, and performance. In addition to FDA’s advancement of regulatory science, product developers bear the onus of generating high-quality objective data at key stages throughout the product life cycle that can be effectively and efficiently reviewed. To spur collaboration between FDA and product developers, this review paper provides a discussion about how regulatory science can be leveraged to improve the demonstration of product identity and potency testing for regenerative medicine cellular products.
Power Junction Field Effect Transistors

Fig. 8.1 shows the structure and doping profile Baliga, 1982b of the JFET investigated in this study. This structure has been shown to provide superior forward blocking and on-state characteristics as compared to other JFET structures. The gates in the JFET are formed by P+ diffusions into trenches so that more effective channel pinch off can be achieved in the forward blocking mode. To operate a JFET in the forward blocking mode, a sufficiently large negative bias is applied to the gate to form a potential barrier in the N- region between the gate diffusions (channel) that prevents the flow of current. As the negative bias on the gate is increased, the JFET changes from pentode-like behavior to triode-like behavior after forward blocking is achieved. At elevated negative gate biases, these devices show an absolute maxima in the drain blocking voltage for a particular device design. This is called the maximum blocking voltage of the device. Depending on the design of the JFET, this capability may be limited by either the avalanche breakdown of the gate-source junction or the device edge termination. To switch the device from the on-state to the forward blocking state, a negative gate bias is applied. Being a majority carrier device, the JFET turns off immediately because the current flow path is blocked by the depletion regions extending from the adjoining gates.
Chapter 8 Regulation of Amiloride-Sensitive Na+ Channels in the Renal Collecting Duct

Publisher Summary The chapter presents a study on regulation of amiloride-sensitive sodium ion (Na + ) channel (ASSC) in the renal collecting duct. The important point in the context of the present discussion is that single gene defects that result in unregulated Na + reabsorption by the cortical collecting duct (CCD) are sufficient to produce severe hypertension. These abnormalities can arise anywhere in the pathway between the Na + channel itself and the hormones that regulate it, including receptors, G-proteins, phospholipases, protein kinases, and other intracellular second messengers. This chapter presents an analysis on the association between some of these other elements and the regulation of epithelial Na + channel (ENaC) subunits in the CCD. The chapter discusses that vasopressin can act as an antinatriuretic as well as an antidiuretic hormone. The chapter presents a discussion on autacoids that limit the actions of aldosterone and vasopressin in the CCD, including prostaglandin E 2 as an inhibitory regulator, Ca 2+ and protein kinase C isoforms as intracellular mediators of inhibitory regulation, α-adrenergic inhibition of arginine vasopressin (AVP)-dependent transport in the CCD, and so on.
CREDIT DEFAULT SWAPS – WEAPON OF MASS DESTRUCTION OR RELIABLE INDICATOR?

Credit Default Swaps (CDS) are said to increase systemic vulnerability, but they also serve as an ex-ante indicator of default probabilities, more finely-tuned and more responsive than ratings agency reports. And they provide a useful mechanism for trading risk and an incentive for good management by businesses and governments.
Amino Acid Biosynthesis in the Spirochete Leptospira: Evidence for a Novel Pathway of Isoleucine Biosynthesis

Radioactive carbon dioxide was incubated with growing cells of Leptospira interrogans serotypes semaranga and tarassovi, and the specific activities and distribution of the label within the cellular amino acids were determined. The origins of the carbon skeletons of all the acid-stable amino acids except isoleucine were found to be consistent with known biosynthetic pathways for these amino acids. Experiments using radioactive carbon dioxide and other tracers indicated that most of the isoleucine was synthesized by a pathway not involving threonine. The origin of the carbon skeleton of isoleucine consisted of two residues of pyruvate (carbons 2 and 3) and acetate of acetyl-coenzyme A by this pathway. Isotope competition studies indicated that the pathway was regulated by isoleucine. The results are discussed in relation to two proposed pathways of isoleucine biosynthesis involving citramalate as an intermediate.
Leukocyte-induced vascular protein leakage in cat mesentery.

The overall objective of this study was to determine whether leukocyte adherence and/or emigration is a prerequisite for the increased vascular protein leakage associated with acute inflammation. A...
Microstructural Characterization Associated with Solid-Solid Transformations

Materials scientists have long been interested in the characterization of complex poly-crystalline systems, as embodied in the distribution of grain size and shape, and have sought to link microstructural features with observed mechanical, electronic and magnetic properties [1]. The importance of detailed microstructural characterization is underscored by systems of limited spatial dimensionality, with length scales of the order of nanometers to microns, as their reliability and performance are greatly influenced by specific microstructural features rather than by average, bulk properties [2]. For example, the functionalities of many electronic devices depend critically on the microstructure of thin metallic films via the film deposition process and the occurrence of reactive phase formation at metallic contacts.
The evolutionary psychology of small-scale versus large-scale politics: Ancestral conditions did not include large-scale politics

The current research question sought to examine political psychology as it relates to evolutionary mismatch. The basic hypothesis is that people will be more cognitively prepared to think about political situations that are relatively small in scale compared with political situations that are large in scale. This research also examined the effects of whether the political situation is highly relevant to oneself. To test these questions, 49 young adults were presented with four sets of instructions. They were asked to write paragraphs describing (i) a large-scale, self-relevant political situation, (ii) a large-scale non-self-relevant political situation, (iii) a small-scale self-relevant political situation, and (iv) a small-scale non-self-relevant political situation. Paragraphs generated by the participants were analyzed using Tyler's (2013) Writing Sample Readability Analyzer. Results demonstrated that paragraphs designed for large-scale political situations had more sentences and were less readable than paragraphs designed for small-scale situations—while paragraphs designed for small-scale political situations were relatively readable and included more words per sentence, suggesting that, consistent with the core hypothesis, participants had an easier time processing information related to small-scale political situations than large-scale political situations. Implications for the nature of modern politics are discussed.
Current diagnosis and management of medullary thyroid carcinoma

Summary Background Medullary thyroid carcinoma (MTC) originates in the thyroid C cells, accounting for 5% to 10% or all thyroid malignancies. Approximately 75% of cases are sporadic. Significant advances have been made in the molecular biology of MTC, but some aspects of diagnosis and management still remain controversial. Design We reviewed relevant articles published in major English-language medical journals. We used the MEDLINE database, selected bibliographies, and articles available in our personal files. Results Mutations of the RET proto-oncogene have been identified in the germline DNA of patients with familial MTC syndromes. Genetic testing can identify patients affected by multiple endocrine neoplasia types IIA and IIB and familial MTC, allowing early diagnosis and possible cure. Surgical treatment is total thyroidectomy. Plasma calcitonin measurements are excellent markers for postoperative follow-up. Adjunctive therapy includes radiotherapy and chemotherapy. The overall prognosis is worse than papillary thyroid carcinoma. Conclusions Recent advances in genetic testing allow early diagnosis and treatment of familial MTC syndromes. Despite some advances in treatment, optimal management remains controversial.
SU-GG-T-316: Measurement of Photoneutron Depth Dose Equivalent and Beam Profiles of a High-Energy X-Ray Beam of Varian 2100C Medical Linear Accelerator by Thermoluminescent and CR-39 Detectors

Purpose: To measure depth‐dose‐equivalent(DDE) and beam‐profiles(BP) of photoneutrons produced by 18MV photon beam. Materials and Methods: 18MV photon beam of Varian‐2100C LINAC was used to measure DDE and BP of photoneutrons. Specially designed dry‐phantom, to accommodate Thermoluminescent(TL) and CR‐39 detectors, was used. Mixer of photons and photoneutrons, and photons were measured by TLD‐600 and LTD‐700, respectively. Glow curves were generated at calibration depth of 6MV beam of 10×10cm2 for dose range 0–400cGy. DDE measured at depths 0–20cm for 5×5–30×30cm2, while BP at dmax and 10cm in cross‐plane for 10×10cm2 and 20×20cm2. Measurements were done upto 15cm beyond the photon field edge. TLDs were read by Harshaw reader and CR‐39 by the supplier(Landauer). Factors in 10CFR20 regulation were used for DE conversion. Results:TLDs provided DE for total neutrons, while CR‐39 for total, fast plus intermediate and thermal neutrons. DDE obtained by normalizing DE with that at dmax(photons). DDE for total neutron DE, of both detectors, decrease exponentially with depth and have no statistically significant differences(p>0.05). DDE for fast plus intermediate neutrons(CR‐39) also decreases exponentially with depth, while DDE for thermal neutrons exhibit buildup region and attain maximum at depth, thereafter decreases in samilar manner as photons depth doses. Central axis DE, for all type of neutrons, at 0 and dmax increases with field size. BP at dmax and 10cm for total neutron DE, have maximum normalized values at central axis and remain almost constant within 90% photon isodose region and then decreases rapidly between 90%−20% photon isodose region. Beyond 20% to the end point of measurement the decrease is only 5%. Conclusion: Study demonstrates the way to measure DDE and BP for photoneutrons and will help to compute neutron DE in critical organs and can eliminate the fear of using high‐energy photons beams in IMRT and IGRT treatments.
Clinical Policy: Critical Issues in the Evaluation and Management of Adult Patients With Asymptomatic Hypertension in the Emergency Department

Andy S. Jagoda, MD (Chair, 2003-2006) Wyatt W. Decker, MD Jonathan A. Edlow, MD Francis M. Fesmire, MD Steven A. Godwin, MD Sigrid A. Hahn, MD (EMRA Representative 2003-2004) John M. Howell, MD J. Stephen Huff, MD Thomas W. Lukens, MD, PhD Donna L. Mason, RN, MS, CEN (ENA Representative 2005) Michael Moon, RN, CNS, MSN, CEN (ENA Representative 2004) Anthony M. Napoli, MD (EMRA Representative 2004-
Tribological Characterization of Aromatic Thermosetting Copolyester–PTFE Blends in Air Conditioning Compressor Environment

The tribological behavior of a wide range of compositions using blends of aromatic thermosetting polyester (ATSP) with polytetrafluoroethylene (PTFE) has been investigated. PTFE was chosen as the blending material because of its low coefficient of friction and good performance at high temperatures and resistance to chemicals. ATSP blends were used to specifically combat some of the shortcomings of PTFE like its extremely low wear resistance and poor mechanical properties, and special processing requirements due to its high melt viscosity. Controlled tribological experiments simulating an air conditioning compressor operating with R134a refrigerant under realistic operating conditions were carried out with different ATSP/PTFE compositions, as well as four different state-of-the-art commercially available composites containing carbon fibers, graphite and PTFE. It was found that the newly synthesized composites exhibited superb tribological characteristics as far as low friction and low wear were concerned. The wear performance of PTFE was greatly improved, while it was shown that greater amounts of ATSP used in the blend lead to lower wear and the amount of ATSP did not significantly alter the friction coefficient. Material transfer and development of a weak film on the disk surface was observed, especially for the blends with higher PTFE content.
Toxicity of heavy metals for microorganisms isolated from slow sand filter schmutzdecke

Abstract This paper describes the susceptibility of three species of environmental bacteria isolated from the schmutzdecke of biologically active slow sand filters to cadmium, chromium and lead. The microorganisms, all identified as members of the genus Pseudomonas, were grown in tryptic soy broth with various concentrations of the selected heavy metals. The mean generation times (MGT) of the bacteria were compared to evaluate the toxic effects of the heavy metals. All three species tolerated high doses of heavy metals and the MGTs increased exponentially as the heavy metal concentrations increased; 12 mg I‐1 was die highest dose tested and the bacteria continued to grow albeit at very slow rates. In dilute media, the toxic effects of heavy metals were enhanced, illustrating the protection effect of organic matter and heavy metal complex formation. Growth studies of the isolated microorganisms on half‐strength tryptic soy agar containing 6 mg I‐1 heavy metals also proved useful in determining toxidty.
The patient as text: a model of clinical hermeneutics.

The art of interpretation has traditionally been an integral part of medical practice, but little attention has been devoted to its theory. Hermeneutics or the study of interpretation has grown as a methodological interest primarily within the humanities. Borrowing from the medieval fourfold sense of scripture, which organizes interpretive activity both logically and comprehensively, I propose a hermeneutical model of clinical decision-making. According to the model, a patient is analogous to a literary text which may be interpreted on four levels: (1) the literal facts of the patient's body and the literal story told by the patient, (2) the diagnostic meaning of the literal data, (3) the praxis (prognosis and therapeutic decisions) emanating from the diagnosis, and (4) the change effected by the clinical encounter in both the patient's and clinician's life-worlds. The model is illustrated through application to a medical case.
Photoemissive effects and associated stresses in ultrafine transmission grating structures irradiated with synchrotron light

Abstract In this paper, we present a first-order analysis of photoemissive electrification and associated mechanical effects in ultrafine transmission grating structures. The analysis indicates that such effects may be viewed as being of second order in current typical grounded gratings, but that they may prove to be important in ungrounded gratings, and also in grounded gratings an order of magnitude finer than those presently available.
Female dimorphism and mating behaviour in a damselfly, Ischnura ramburi: females mimicking males

Females of the damselfly Ischnura ramburi exhibit a simple genetic colour dimorphism in which one form is cryptic (heteromorph), and the other closely resembles the more conspicuously colourful males (andromorph). Andromorphs also mimic male behaviour in interactions with males. Consequently they copulate half as often as do heteromorphs, which may give them a frequency-dependent selective advantage. Assuming that females need only mate once, excessive copulations, which average 3 h in duration, waste time for heteromorphs and may expose them to increased predation. The peculiar biology and mating behaviour of ischnurans provides a possible evolutionary context for this mimicry. The polymorphism is probably balanced by a frequency-independent selective disadvantage suffered by the more conspicuous andromorphs, through increased predation.
AGE AND STARVATION EFFECTS ON HYPERTREHALOSEMIC HORMONE-DEPENDENT GENE EXPRESSION OF CYTOCHROME P4504C1 IN THE COCKROACH, BLABERUS DISCOIDALIS

Abstract Expression of the gene for cytochrome P4504C1 (= CYP4C1 ) is stimulated by the hypertrehalosemic hormone (= Bld-HrTH) in the fat body of the cockroach Blaberus discoidalis . The natural pattern for CYP4C1 expression was determined for the fat body of adult male B. discoidalis , and effects by the absence of food and water were assessed. CYP4C1-mRNA levels did not change significantly in the fat body of fed insects during the first 10 days of adult life; however, absence of food and water increased the CYP4C1 expression by 2.5 to 5 times that of fed animals. Decapitation prevented the starvation-related increase in gene expression indicating that the starvation effect was mediated by the head. Starvation-induced CYP4C1 expression was suppressed to the level of normally fed insects following re-exposure to food and water. Insects from which the corpora cardiaca (the endocrine source of Bld-HrTH) were extirpated did not exhibit the starvation-related increase in CYP4C1 expression. The increase in CYP4C1 expression during restriction from food and water was related to the absence of food since insects provided water without food still showed increased CYP4C1 expression. These results suggest that restriction from food consumption stimulates the secretion of Bld-HrTH which results in increased CYP4C1 expression. It is speculated that cytochrome P4504C1 participates in fatty acid metabolism that is regulated by Bld-HrTH as an adaptation to starvation.
Ubiquilin1 represses migration and epithelial-to-mesenchymal transition of human non-small cell lung cancer cells

Ubiquilin1 (UBQLN1) is a ubiquitin-like domain and a ubiquitin-associated domain containing protein that has been reported to be involved in shuttling proteins to the proteasome, especially during endoplasmic reticulum-associated protein degradation. Thus, UBQLN1 function has been shown to be critical for combating a number of neurological disorders caused by protein aggregation, such as amyotrophic lateral sclerosis, Alzheimer's disease and Huntington's disease. A role for UBQLN1 in regulating processes involved in tumorigenesis has not been demonstrated. Herein, we show that loss of UBQLN1 causes increased cell migration and invasion, actin cytoskeleton reorganization and induction of epithelial-to-mesenchymal transition (EMT). Loss of UBQLN1 results in a significant decrease in the expression of epithelial markers including E-cadherin and claudin1, whereas expression of mesenchymal markers including Vimentin, Snail and ZEB1 are significantly elevated. Interestingly, we found that ZEB1 is required for induction of mesenchymal-like properties following loss of UBQLN1 and ZEB1 is capable of repressing expression of UBQLN1, suggesting a physiological, reciprocal regulation of EMT by UBQLN1 and ZEB1. Further, we find evidence for a role for UBQLN2 in also regulating EMT and cell migration. These observations have potential clinical relevance because the UBQLN1 gene is lost and underexpressed in a large percentage of human cancer cell lines, and primary human lung cancer samples and recurrent mutations in all five UBQLN family members have been identified in human lung cancers. Taken together, our results suggest for the first time a role for UBQLN family members in cancer biology.
Local and regional variations in myofibrillar patterns in looping rat hearts

Background: In chickens, cytodifferentiation, right side dominance in myofibril development, and variations in myofibrillar pat- terns in different areas and layers of the myocardial wall exist which have been implicated in the process of heart looping. Little comparable informa- tion is available for developing myofibrillar patterns in the early develop- ment of mammalian hearts. Methods: We have used transmission electron microscopy (TEM), confo- cal scanning laser microscopy (CSLM), and 3-D reconstruction techniques to determine if similar variations to those which exist in the chicken are also present in the looping hearts of embryonic day (ED) 9.5 to 11.5 rat hearts. Results: Local and regional variations and right side dominance in myo- fibrillar patterns were shown during looping in 9.5 through 11.5 days of development in embryonic rat heart. At 9.5 days of development, myofibrils near the lumen of the myocardial wall were primarily in circumferential bands while near the pericardial surface they were primarily in longitudi- nal bands. In older embryos, regional variations in myofibrillar organiza- tion was found in areas associated with the cardiac cushions, trabeculae, and myocardial wall of the developing heart chambers. Based on sarco- meric structure, myofibrils in the ventricle and outflow tract were more advanced than those found in the atrial wall. Conclusions: The local and regional patterns of myofibrils in looping rat hearts are similar to those which have been found in developing chicken hearts. This study and others indicate cytodifferentiation and development of the contractile apparatus has a crucial role in the process of heart looping. o 1996 Wiley-Liss, Inc.
An improved zero-one law for algorithmically random sequences

Abstract Results on random oracles typically involve showing that a class {ifX:P(X)} has Lebesgue measure one, i.e., that some property P ( X ) holds for “almost every X ”. A potentially more informative approach is to show that P ( X ) is true for every X in some explicitly defined class of random sequences or languages. In this note we consider the algorithmically random sequences originally defined by Martin-Lof and their generalizations, the n -random sequences. Our result is an effective form of the classical zero-one law: for each n ≥ 1, if a class {ifX:P(X)} is closed under finite variation and has arithmetical complexity σ 0 n +1 or Π 0 n +1 (roughly, the property P can be expressed with n +1 alternations of quantifiers), then either P holds for every n -random sequence or else holds for none of them. This result has been used by Book and Mayordomo to give new characterizations of complexity classes of the form ALMOST-oR, the languages which can be ≤ oR -reduced to almost every oracle, where oR is a reducibility.
The metabolism of glucosamine by tissue culture cells.

Summary The uptake of 14 C-1-glucosamine by HeLa cells and its subsequent fate has been studied. Over 90 per cent of the label initially taken up by the cells is found in the uridine diphosphate- N -acetylhexosamine pool. This pool loses its label in 12 hr and the radioactivity is found in the aminosugar residues of cell components. Eventually, two thirds of the label is secreted into the media as high molecular-weight compounds that contain aminosugar while one third of the label remains with the cells and is gradually metabolized. Labeling of cells in culture with glucosamine 14 C provides a sensitive means for studying cell components that contain aminosugars.
Quantum posts with tailored structural, electronic and optical properties for optoelectronic and quantum electronic device applications

This article reviews the fabrication, structural and optical properties of self-assembled In(Ga)As quantum posts. We introduce the growth mechanism and present the resulting structural properties and electronic structure which provides a direct route to tunable intraband transitions. We show that in the interband spectrum, sharp optical transitions, single photon emission and tailored giant electrostatic dipole moments are observed. We demonstrate that these properties can be used for an exciton memory.
Characterization of the syndrome of small and large intestinal variceal bleeding

Massive bleeding from jejunal varices in a young alcoholic with cirrhosis and portal hypertension ceased following a portocaval shunt. Although rare, bleeding from small or large bowel varices has a high mortality. In 62 cases, small or large bowel varices are almost always associated with a predisposing condition including previous abdominal surgery and portal hypertension from cirrhosis or other causes. Hematochezia without hematemesis and nonbleeding esophageal varices generally occur. Angiography is the best diagnostic test.
Psychological profile of college students who use smokeless tobacco

Abstract The purpose of this study was to develop a psychological profile of smokeless tobacco users. We surveyed 1991 college students regarding their use of tobacco products. Twenty-one percent of the white males used smokeless tobacco compared to only 10.4% of blacks, 5.4% of Hispanics, and 5.4% of others, primarily Asians. Although the prevalence of smokeless tobacco use reported by Asians was relatively low, their rate of reported smoking was over twice s high as any other enthnic group, 43.6%. The most important reasons for beginning to use smokeless tobacco were to “see if I would enjoy it,” ‘most friends used it,” and “try something new.” The personality of the smokeless tobacco users differed from that of smokers and non-users of tobacco. College students with the highest probability of being a smokeless tobacco user were white males who scored higher in extraversion and neuroticism but lower on state anxiety than non-users.