cssi/SciSciGPT-SciSciNet huggingface dataset:
Evolving Challenges in Pediatric Pulmonary Medicine. New Opportunities to Reinvigorate the Field.

Thirty years after the first board certification examination for pediatric pulmonology was administered there remain substantial challenges in attracting trainees and sustaining and retaining clinician-scientists in the field. In fact, significant workforce shortages are predicted to exist with current fellowship graduation rates and the aging of the existing workforce. However, the rapid diagnostic and therapeutic advances occurring in the field should serve as draw for trainees. In addition, pediatric pulmonologists provide unique expertise for the diversity and severity of respiratory conditions that is not duplicated by generalists, allergists, intensivists, or neonatologists. It is critical to raise awareness of the depth of pediatric pulmonology, not only to trainees, but also of the broader medical community at large, to recognize the value pediatric pulmonologists bring to clinical care, research endeavors, and interdisciplinary collaborations. In this perspective, we highlight the nature of the c...
Optical Behavior of Polymer Blends

Publisher Summary This chapter focusses on the optical behavior of polymer blends. The study of the optical properties of polymer blends is of interest for two reasons. A blend, being composed of two or more components, will scatter light. This may result in blend being cloudy or turbid in appearance, a property that affects the marketability of a polymer, particularly for applications such as containers and films. Also, the scattering and other optical properties such as birefringence and dichroism convey information about the structure of the blend that is desirable for the understanding of its mechanical, electrical, thermal, and other physical properties. The chapter also discusses other optical properties of blends such as birefringence, infrared dichroism, and Raman polarization. The interpretation of birefringence is often ambiguous because of its being a composite property reflecting the combined orientation of both phases whereas infrared dichroism has the potential of selectively measuring the orientation of a particular phase. In principle, the Raman polarization technique can be used to selectively study the orientation of components of a blend in a similar manner to infrared dichroism. The Raman technique has an advantage over the infrared technique in that samples of small size and appreciable thickness may be employed rather than the thin films usually required for infrared dichroism studies. The study of birefringence and infrared dichroism provides information about the deformation mechanisms of the blends that are dependent upon their morphology.
MentorMatch: Using student mentors to scaffold participation and learning within an online discussion board

In this paper, we present a novel approach to scaffolding student participation and learning within discussion forums using student mentors, i.e., course peers with relatively good understanding of a particular domain topic. First, we identify mentors using domain topic models, student discussion profiles, and a similarity comparison of the topics being discussed. Second, we provide an interface that encourages classmates to invite mentors to participate. The feature, named MentorMatch, was integrated into an undergraduate course discussion board. Some results are reported.
Resilience and the coevolution of interdependent multiplex networks

We propose a new model for the study of resilience of coevolving multiplex scale-free networks. Our network model, called preferential interdependent networks, is a novel continuum over scale-free networks parameterized by their correlation p, 0 ≤ $p$ ≤1. Our failure and recovery model ties the propensity of a node, both to fail and to assist in recovery, to its importance. We show, analytically, that our network model can achieve any γ, 2 ≤ γ ≤ 3 for the exponent of the power law of the degree distribution; this is superior to existing multiplex models and allows us better fidelity in representing real-world networks. Our failure and recovery model is also a departure from the much studied cascading error model based on the giant component; it allows for surviving important nodes to send assistance to the damaged nodes to enable their recovery. This better reflects the reality of recovery in man-made networks such as social networks and infrastructure networks. Our main finding, based on simulations, is that resilient preferential interdependent networks are those in which the layers are neither completely correlated (p = 1) nor completely uncorrelated (p= 0) but instead semi-correlated (p ≈ 0.1 – 0.3). This finding is consistent with the real-world experience where complex man-made networks typically bounce back quickly from stress. In an attempt to explain our intriguing empirical discovery we present an argument for why semi-correlated multiplex networks can be the most resilient. Our argument can be seen as an explanation of plausibility or as an incomplete mathematical proof subject to certain technical conjectures that we make explicit.
"We Need More Than Laptops!": Technology Assistance for Transitioning International Students

Although information and communication technologies (ICT's) have become pervasive across various aspects of human endeavors including educational settings, their adoption and diffusion vary among different developing and developed countries, often described as the digital divide. In this work, we examined concerns and considerations of students from developing countries transitioning into graduate and undergraduate studies in developed nations and assessed the personal and institutional resources available to them during their transition along with specific focus on the degree of their exposure to ICT's before and after their transition. The results showed that respondents had experienced different levels of technology exposure in their home countries, and that neither their sources of assistance in their home countries nor in their host countries provided the required aid for transitioning across the digital divide.
Racial/Ethnic Differences in Illicit Substance Use: A Temporal-Ordered Test of General Strain Theory:

This longitudinal study applied general strain theory to elaborate specific stressful events’ lagged effects on risk of illicit substance use among non-Hispanic White, non-Hispanic Black, and Hispa...
Barbed Voices: Oral History, Resistance, and the World War II Japanese American Social Disaster: By Arthur A. Hansen. Foreword by Lane Ryo Hirabayashi. Louisville, CO: University Press of Colorado, 2018. 326 pp. 978-1-60732-811-7, Hardcover, $38.00

Every six to eight years, events conspire to re-spark my interest in twentieth century Japanese-American History. In 1999, while working at the Idaho Oral History Center, we received a donation of ...
Diagramming as a Strategy for Primary/Elementary-Age Program Comprehension

Worldwide, many countries are implementing Computer Science (CS) and Computational Thinking (CT) instruction at the primary and secondary school level. This push for CS/CT instruction in younger ages increases the need for pedagogical practices, such as learning strategies, that are effective for a wide array of learners. However, research into strategies for young learners is relatively sparse, especially compared with strategies at the university level. This study aims to investigate a commonly used practice at the university level, diagramming, as a potential strategy for students in grades 4-8 (ages 10-15). Our hope is that diagramming can be added to a suite of strategies to support program comprehension in younger learners.
"Looking at Myself in the Future": how mentoring shapes scientific identity for STEM students from underrepresented groups.

Mentorship has been well-established in the literature as fostering scientific identity and career pathways for underrepresented minority students in science, technology, engineering, and mathematics (STEM) fields. Mentorship is prioritized by programs that aim to increase diversity and support future leadership in STEM fields, but in-depth understanding of mentorship in these contexts remains limited. Drawing on qualitative interview data, we sought to understand the relationship between mentoring and scientific identity among a diverse sample of 24 students in one such program, in order to inform program development. Qualitative analysis of the data revealed that mentorship, especially research mentorship, was common and played a role in formation of scientific identity. Students with research mentors tended to say they strongly identified as scientists, whereas those who lacked research mentorship varied in their level of scientific identity. In interviews, research-mentored students described mentors as colleagues who gave them opportunities to grow and as examples to look up to. Students valued mentors with whom they identified on the basis of demographic similarity or shared values, as well as those who challenged them in their academic and research endeavors. Our analysis highlights how different mentoring experiences can contribute to development of future STEM leadership. We discuss implications for practice, including the need for tailored mentoring approaches and research-focused mentoring, and offer several recommendations for research and programming.
Diode Pumped Alkali Lasers

Diode pumped alkali lasers attract growing attention during the past several years because they have demonstrated potential to compete and, possibly, replace the best existing high power laser systems. In spite of the fact that an optically pumped alkali (potassium) vapor laser was first proposed by A.L. Schawlow and C.H. Townes in 1958, the intensive research and development of alkali vapor started only in 2003, when really efficient lasing in Rb and Cs vapors was demonstrated. The interest to this research was stimulated by the possibility of using efficient diode lasers for optical pumping of the alkali gain medium that promises high overall efficiency of the device. A variety of experiments on alkali lasers, including the demonstration of efficient Rb, Cs and K vapor lasers, power scaling experiments with multiple diode laser pumping sources and experiments on diode pumped alkali vapor amplifiers were performed during the past several years. In this paper we present a review of the most important achievements in high power alkali lasers research and development, discuss some problems existing in this field and future perspectives in DPAL development.
Trace identities and direct sums of triangular matrices

We construct a counterexample to the conjecture that all trace identities of An are consequences of the ordinary polynomial identities of A and the trace identities of A⊗Mn(F). We also describe the...
Continued Trauma: A Thematic Analysis of the Asylum-Seeking Experience Under the Migrant Protection Protocols.

Introduction: The Migrant Protection Protocols (MPP) required asylum seekers presenting to the U.S. southern border to wait in Mexico while seeking asylum. Currently, there is a lack of understandi...
Note on UK FOIA Referrals to Cabinet Office

This note provides a brief description and analysis of Freedom of Information Act requests referred to the UK Cabinet Office between January 2005 and May 2009. A list of the referred requests is also included. The data is available in spreadsheet form from the author.
Attraction of Mature Ceratitis capitata Females to 2-Heptanone, A Component of Coffee Fruit Odor

In indoor laboratory-cage and outdoor field-cage assays, we evaluated the attraction of released, protein-fed, mature Mediterranean fruit fly females to six volatile compounds emitted by attractive crushed ripe coffee fruit: 3-methyl-1-butanal, decanal, 3-methyl-1-butanol, 2-(Z)-pentenol, 2-(E)-hexenol, and 2-heptanone. Previous tests in a wind tunnel indicated that each of these six compounds was more attractive than clean air to females. In laboratory cage assays, none of the compounds elicited a response significantly greater than that to water. In field-cage assays, 2 or 4 μl of 2-heptanone in 5 ml of water (but none of the other compounds at 2 or 4 μl in 5 ml of water) consistently attracted protein-fed medflies at significant levels that averaged about five times greater than attraction to water alone, although about 40% less than attraction to odor of coffee fruit extract. All types of mature protein-fed females tested (laboratory-cultured virgin, laboratory-cultured mated, wild mated) in field-cage assays responded similarly to 2-heptanone, whereas same-age (9- to 11-day-old) protein-deprived females did not respond significantly to 2-heptanone. Response of protein-fed females to 2-heptanone increased progressively with increasing dose (1, 2, 4, or 8 μl in 5 ml of water). Addition of 2 μl of 2-heptanone or 2 μl of any of the other compounds tested to 5 ml of water extract of coffee fruit did not enhance attractiveness of the extract. Relative to response to water, protein-fed females consistently exhibited a significant positive response to odor of coffee fruit extract but no significant response to odor of Nulure (a proteinaceous food attractant). Together, our findings suggest that mature protein-fed females were responding to 2-heptanone as though it were an oviposition-site stimulus rather than a feeding-site stimulus.
Abstract T P331: Collaborative Multidisciplanary Approach in the Development and Implementation of an Aspiration Risk Tool Within a Certified Comprehensive Stroke Program

Background and Issues: Dysphagia is the leading neurological cause of aspiration pneumonia in stroke patients. Swallowing abnormalities are associated with a 3-fold higher mortality rate. Accreditation agencies and the American Stroke Association recommend institutions establish a dysphagia screening tool for stroke patients. Early identification decreases adverse health consequences and increases patient family satisfaction. Purpose: A multidisciplinary team of nurses and speech and language pathologists developed criteria to improve the identification of patients at risk for aspiration and created standardized tool. Methods: A review of the literature provided the frame work to formalize a screening tool. The tool assists the nurse in identifying patients at risk. The screening tool is divided into four sections; cognition, cough assessment, control of oral secretions and oral motor strength. It is required for the patient to pass all four levels. Failure to pass any one of the sections results in a for...
Kazdin, A. E. (2011). Single-Case Research Designs, Second Edition.

Alan Kazdin, Professor of Psychology and Child Psychiatry at Yale University, is Director of the Yale Parenting Center and Child Conduct Clinic. The author of Research Design in Clinical Psychology...
Studies on Deoxyribonucleic Acid Polymerase from Ehrlich Ascites Tumor Cells II. FACTORS INFLUENCING PRIMER AND TEMPLATE REQUIREMENT OF DEOXYRIBONUCLEIC ACID POLYMERASE

Abstract The DNA polymerase activity of preparations obtained from Ehrlich ascites cells by hypotonic shock was found to become increasingly dependent upon single strand DNA as promoter during the course of purification. The ability of crude preparations to utilize native DNA to promote synthesis reflected the presence of endonuclease activity. With the use of highly purified preparations the maximum activity was achieved with denatured DNA that had been digested with pancreatic DNase to the extent that 25% of the DNA was rendered acid-soluble. More extensive hydrolysis resulted in drastic inhibition of the reaction. The extent of incorporation, when oligonucleotides were used as promoter, varied widely depending on the molecular sizes of the oligonucleotide. Addition of high molecular weight polymer to low molecular weight polymer was found to enhance promoter activity to levels far greater than those expected by summation of the activities of these promoters used individually. It is concluded that the smaller molecules act as primer but that template function requires a larger size. The polymerase activity of the purified preparation was found to be promoted by oligonucleotides with 5'-phosphoryl and 3'-hydroxyl termini, but inhibited by oligonucleotides with 5'-hydroxyl and 3'-phosphoryl termini. The maximum net increase in DNA attained by the purified enzyme, using denatured DNA, was equivalent to 66% of the DNA used to promote synthesis.
Intrusion-resilient key exchange in the bounded retrieval model

We construct an intrusion-resilient symmetric-key authenticated key exchange (AKE) protocol in the bounded retrieval model. The model employs a long shared private key to cope with an active adversary who can repeatedly compromise the user's machine and perform any efficient computation on the entire shared key. However, we assume that the attacker is communication bounded and unable to retrieve too much information during each successive break-in. In contrast, the users read only a small portion of the shared key, making the model quite realistic in situations where storage is much cheaper than bandwidth. The problem was first studied by Dziembowski [Dzi06a], who constructed a secure AKE protocol using random oracles. We present a general paradigm for constructing intrusion-resilient AKE protocols in this model, and show how to instantiate it without random oracles. The main ingredients of our construction are UC-secure password authenticated key exchange and tools from the bounded storage model.
People-to-People Lending: The Emerging e-Commerce Transformation of a Financial Market

This paper provides an overview of the concept of people-to-people (P2P) lending, a relatively new e-commerce phenomenon that has the potential to radically change the structure of the loan segment of the financial industry. P2P lending creates a marketplace of individuals and a social fabric through which these individuals interact. It provides efficient information transfer, thus perhaps creating more perfect markets. P2P lending requires information systems support to make it function, and to provide a social network mechanism that may be crucial for its success. We discuss different P2P lending marketplace models, and how information systems support the creation and management of these new marketplaces, and how they support the individuals involved. We conclude by providing some important research questions and directions, and issues for which further investigation is called.
Marcuse, Bloch and Freire: Reinvigorating a Pedagogy of Hope.

Critique of the current order of things is a necessary starting point for any project for radical change. Without an analysis of what is wrong, it is hard to convince anyone that change is necessary. And yet critique alone rarely inspires people to act. We need something to fight for as well as against. The article looks at the centrality of hope as a necessary complement to critique. Combining insights from Freire, Bloch and Marcuse, it argues that critical pedagogy needs to seriously engage methods to create an environment amenable to resistance and struggle for change, founded on a belief that a better world is possible. Marcuse, in particular, offers three key insights that can be instrumental in moving beyond the overly negative discourse and cynicism that prevail today – including a trenchant analysis of capitalism and desire, a program for aesthetic education and a model for utopian dreaming and embodied hope. It is argued that critical pedagogy must move beyond consciousness raising and identity f...
Is the combination of cellulosic polymers and anionic surfactants a good strategy for ensuring physical stability of BCS Class II drug nanosuspensions

AbstractEnsuring the physical stability of drug nanosuspensions prepared via wet media milling has been a challenge for pharmaceutical scientists. The aim of this study is to assess the combined use of non-ionic cellulosic polymers and anionic surfactants in stabilizing multiple drug nanosuspensions. Particle size of five drugs, i.e. azodicarbonamide (AZD), fenofibrate (FNB), griseofulvin (GF), ibuprofen (IBU) and phenylbutazone (PB) was reduced separately in an aqueous solution of hydroxypropyl cellulose (HPC) with/without sodium dodecyl sulfate (SDS) via a stirred media mill. Laser diffraction, scanning electron microscopy, thermal analysis, rheometry and electrophoresis were used to evaluate the breakage kinetics, storage stability, electrostatic repulsion and stabilizer adsorption. Without SDS, drug particles exhibited aggregation to different extents; FNB and GF particles aggregated the most due to low zeta potential and insufficient steric stabilization. Although aggregation in all milled suspension...
Hospital revisit rate after a diagnosis of conversion disorder

Objective To estimate the hospital revisit rate of patients diagnosed with conversion disorder (CD). Methods Using administrative data, we identified all patients discharged from California, Florida and New York emergency departments (EDs) and acute care hospitals between 2005 and 2011 with a primary discharge diagnosis of CD. Patients discharged with a primary diagnosis of seizure or transient global amnesia (TGA) served as control groups. Our primary outcome was the rate of repeat ED visits and hospital admissions after initial presentation. Poisson regression was used to compare rates between diagnosis groups while adjusting for demographic characteristics. Results We identified 7946 patients discharged with a primary diagnosis of CD. During a mean follow-up of 3.0 (±1.6) years, patients with CD had a median of three (IQR, 1–9) ED or inpatient revisits, compared with 0 (IQR, 0–2) in patients with TGA and 3 (IQR, 1–7) in those with seizures. Revisit rates were 18.25 (95% CI, 18.10 to 18.40) visits per 100 patients per month in those with CD, 3.90 (95% CI, 3.84 to 3.95) in those with TGA and 17.78 (95% CI, 17.75 to 17.81) in those with seizures. As compared to CD, the incidence rate ratio for repeat ED visits or hospitalisations was 0.89 (95% CI, 0.86 to 0.93) for seizure disorder and 0.32 (95% CI 0.31 to 0.34) for TGA. Conclusions CD is associated with a substantial hospital revisit rate. Our findings suggest that CD is not an acute, time-limited response to stress, but rather that CD is a manifestation of a broader pattern of chronic neuropsychiatric disease.
Resuscitation Policy Concerning Older Adults: Ethical Considerations of Paternalism Versus Autonomy

The heated national debate concerning health care must include a discussion of a patient's wishes and the implications of his or her right to determine individual medical treatment decisions, especially at the end of life. This article is an examination of physician paternalism versus patient autonomy concerning do-not-resuscitate (DNR) orders within the context of utilitarian ethical theory. The author proposes effective compromise between the two; consideration of decision making on a case-by-case basis; enhanced education for all actors concerning cardiopulminary resucitation (CPR), DNR, and advanced directives; and consensus reached through democratic debate regarding the allocation of health care resources.
The use of 2-hydroxypropyl-β-cyclodextrin as a vehicle for intravenous administration of dexamethasone in dogs

Abstract Dexamethasone (Dex) was administered to 6 mongrel dogs in a dose of 5 mg/kg as the sodium salt of its phosphate ester or as an inclusion complex in 2-hydroxypropyl-β-cyclodextrin (HPCD). Blood and urine were collected and analyzed for dexamethasone by HPLC. The area under the plasma concentration time curve (AUC) of dexamethasone during the first hour was significantly greater after the administration of the Dex-HPCD complex compared to the phosphate ester prodrug (1.63 ± 0.13 vs 1.04 ± 0.10 μ g h ml −1 ). In addition, the renal clearance (CL ren ) was significantly higher after administration of the HPCD form (0.91 ± 0.20 vs 0.52 ± 0.20 ml min −1 kg −1 ). There was no difference between treatments for other pharmacokinetic parameters of dexamethasone. Hence, intravenous injection of dexamethasone in HPCD allows direct administration of this poorly soluble steroid without any prodrug conversion. The higher plasma levels during the first hour after administration may be advantageous for the treament of emergency situations.
Channel piracy on Monterey Deep-Sea Fan

Abstract The present Monterey Fan-Valley extends 300 km across the Monterey Deep-Sea Fan with a 400 m relief on the upper fan where large levees border the western bank. Seismic reflection profiling on the upper fan suggests that extensive erosion within Monterey Fan-Valley increased its relief by at least 200 m after it had taken over the lower end of the parallel Ascension Fan-Valley. At present, the latter enters the Monterey Fan-Valley as a hanging valley. A beheaded, leveed valley, the Monterey East Fan-Valley, marks the old course of the Monterey Fan-Valley.
Msx1 and Pax3 Cooperate to Mediate FGF8 and WNT Signals during Xenopus Neural Crest Induction

FGF, WNT, and BMP signaling promote neural crest formation at the neural plate boundary in vertebrate embryos. To understand how these signals are integrated, we have analyzed the role of the transcription factors Msx1 and Pax3. Using a combination of overexpression and morpholino-mediated knockdown strategies in Xenopus, we show that Msx1 and Pax3 are both required for neural crest formation, display overlapping but nonidentical activities, and that Pax3 acts downstream of Msx1. In neuralized ectoderm, Msx1 is sufficient to induce multiple early neural crest genes. Msx1 induces Pax3 and ZicR1 cell autonomously, in turn, Pax3 combined with ZicR1 activates Slug in a WNT-dependent manner. Upstream of this, WNTs initiate Slug induction through Pax3 activity, whereas FGF8 induces neural crest through both Msx1 and Pax3 activities. Thus, WNT and FGF8 signals act in parallel at the neural border and converge on Pax3 activity during neural crest induction.
An electron-microscope study of adult mouse lens: some ultrastructural specializations.

The ultrastructure of three regions of adult mouse lens was studied with the transmission electron microscope. Epithelial cells of the central and preequatorial peripheral regions are similar and contain organelles which characterize moderately metabolically active cells. These cells also contain large quantities of 50 A diameter filaments located primarily around the nucleus and in cytoplasmic processes, but which, in cells of older mice, are arrayed in bundles which intersect in a herringbone pattern. The only specialized cell junctions observed are probable gap junctions, but ordinary cell contacts between epithelial cells are nearly twice as wide as contacts between lens fibers, and cell-to-fiber contacts are intermediate. The difference in thickness of cell contacts is due to a narrowed intercellular space and not to plasma membrane thickness. This specialization may be related to physical requirements for optimal light transmission.
Political Discourse and the “New PBS”

Having survived efforts by political conservatives to eliminate federal funding for public broadcasting, public television in the United States remade itself as a market-savvy media enterprise in the mid-1990s. This “new PBS” sought to develop new revenue streams and forge new financial partnerships at the same time that public broadcasting found renewed political support on Capitol Hill. In this climate, this study examines the sources and subjects on public television’s public affairs lineup, exploring how public television measures up to the lofty goal of contributing to public life by providing a diverse alternative to commercial broadcasting. Based on a two-week sample of the eighteen most widely distributed public affairs programs on public television, findings indicate that the vast majority of stories focused on either the economy or domestic politics, while coverage of international issues was comparatively small. More than three-quarters of on-camera sources were corporate representatives, gover...
Electrophysiologic effects of interactions between activated canine neutrophils and cardiac myocytes.

Effects of Neutrophils on Cardiac Myocytes. Introduction: Myocardial ischemia causes neutrophils to bind to activaled myocytes and liberate platelet-activating factor (PAF). PAF causes delayed repolarization, early afterdepolarizations (EADs), and arrest of repolarization. We studied the effect of activation of neutrophils bound to canine cardiac myocytes to determine if such activation causes PAF generation and similar changes in transmembrane potentials. Methods and Results: Myocytes from canine left ventricle and neutrophils from the same dog were superfused with Tyrode's solution and transmembrane potentials recorded from the former. Neutrophils (100 μL, 10-6/mL) were added and allowed to bind to the myocytes. Neutrophils were activated with 1% zymosan-activated serum (ZAS). CV-6209 (100 nM) was used to block receptors for PAF. Liberation of PAF by activated neutrophils was quantified with a commercial radioimmunoassay kit. Neutrophils activated with ZAS caused changes in myocyte transmembrane potentials like those induced by PAF: action potential prolongation, runs of EAD, and periods of plateau arrest. PAF receptor blockade prevented neutrophil activation from altering transmembrane potentials. Neutrophils activated with 1 % ZAS liberated significant amounts of PAF. Conclusions: When neutrophils bound to cardiac myocytes are activated by exposure to 1% ZAS, they cause prompt and consistent changes in myocyte electrical activity that could be arrhythmogenic for the in situ heart. These changes are similar to those caused by PAF in pharmacologic studies. Neutrophils activated in this manner generate PAF, and the effects of their activation are prevented by blockade of PAF receptors. We conclude that, during reperfusion of ischemic myocardium, PAF generated by activated neutrophils most likely is a cause of some arrhythmias.
Practical considerations in the design of optical fiber current sensors

While current sensors based on the Faraday effect in bulk materials have shown good success in field tests, the use of single mode fiber as the sensing element has both technical and economic advantages. In this paper we describe some of the practical problems that have inhibited the development of fiber current sensors. Recent research suggests that most of these problems, including especially the problem of linear birefringence in the sensing coils, can be solved. Instruments providing a measurement quality approaching that set by fundamental material parameters can now be achieved.
Comparison of the flow capacity of free arterial grafts and saphenous vein grafts for coronary bypass surgery1

Abstract There is controversy regarding the flow reserve and capacity of arterial conduits to meet the needs of the myocardium. This study compared flow in 22 free arterial bypasses to 15 saphenous vein grafts in procedures involving twenty patients. To assess the maximal flow possible, (flow capacity) graft flow was measured using a calibrated pump while perfusing blood cardioplegia through the conduit and distal anastomosis during cardiac arrest (no competitive flow). This assessment was subsequently confirmed with whole blood during myocardial contraction while on cardiopulmonary bypass. Twenty-two free arterial grafts were used; 15 right internal mammary artery grafts, 4 right gastroepiploic grafts, 3 inferior epigastric artery grafts, and 3 sequential bypasses. Free arterial conduit flow ranged from 50 to 180 cc/ml, with an average flow of 102.5±28.5 ml/min as compared to saphenous vein graft flow, 102±28 ml/min. No correlation of flow with the conduit size was found. Arterial graft flow demonstrated a mild correlation with the size of the native coronary artery bypassed ( R =0.47, P ≤0.02). Conclusions: Basal flow through free arterial grafts is equivalent to saphenous vein grafts and is primarily determined by the native coronary vessels. The flow reserve for free arterial conduits is more than adequate for coronary bypass surgery.
Postexercise skeletal muscle glucose transport is normal in kininogen-deficient rats.

A single exercise bout stimulates skeletal muscle glucose transport (GT) in the absence or presence of insulin. It has been suggested that the kallikrein-kinin system may contribute to exercise effects on both insulin-independent and insulin-dependent GT. Plasma kininogen, a key kallikrein-kinin system component, is a protein substrate for the enzyme kallikrein and the source of the peptide bradykinin. Purpose: This study aimed to determine whether the postexercise (PEX) increase in insulin-dependent or insulin-independent GT is reduced in rats deficient in plasma kininogen versus normal rats. Methods: Male Brown Norway (BN) and Brown Norway Katholiek (BNK; plasma kininogen-deficient) rats were studied. BN and BNK rats were assigned to exercise (4 × 30-min swim) or sedentary (SED) groups. Rats were anesthetized immediately (0hPEX) or 3 h (3hPEX) after exercise. For 0hPEX and 0hSED rats, one epitrochlearis muscle per rat was used for AMPK phosphorylation and muscle glycogen analyses. The contralateral muscle was incubated with [3H]-3-O-methylglucose (3-MG) for GT assay. For 3hPEX and 3hSED rats, one muscle from each rat was incubated without insulin, and the contralateral muscle was incubated with 60 µU·mL-1 insulin, and both muscles were incubated with 3-MG for GT measurement. Results: For 0hPEX versus 0hSED, both BN and BNK rats had greater insulin-independent GT and AMPK phosphorylation with reduced glycogen after exercise. No genotype effects were found 0hPEX. There was a significant main effect of exercise (3hPEX > 3hSED) and no interaction between exercise and genotype for basal or insulin-stimulated GT. Conclusions: Plasma kininogen deficiency did not alter insulin-independent GT, AMPK phosphorylation, or glycogen depletion 0hPEX or insulin-dependent GT 3hPEX, suggesting that normal plasma kininogen is not essential for these important exercise effects
Death and transfiguration of cortical thymocytes: a reconsideration

The fate of most cells in the mammalian thymus, namely CD4+CD8+ (double positive) cortical cells, is unknown. A fraction of the cells in this population serve as developmental intermediates, but the vast majority will die. In this article Ellen Rothenberg discusses how and when the cells are condemned or promoted to maturity, in the light of intriguing new data that suggests that they may be able to be rescued for longer than was previously thought.
Effects of Land Use and Forest Management on the Carbon Cycle in the Brazilian Amazon

SUMMARY.Deforestation in the Brazilian Legal Amazon releases substantial amounts of greenhouse gases. Net committed emissions (the long-term result of emissions and uptakes in a given area that is cleared) totaled 267-278 million t of CO2-equivalent carbon in 1990 (under low and high trace gas scenarios), while the corresponding annual balance of net emissions (the balance in a single year over the entire region, including areas cleared in previous years) in 1990 was 354-358 million t from deforestation plus 62 t from logging. These figures contrast sharply with official pronouncements that claim little or even no net emission from Amazonia. Most emissions are caused by medium and large ranchers (despite recent official statements to the contrary), a fact which means that deforestation could be greatly slowed without preventing subsistence clearing by small farmers. The substantial monetary and non-monetary benefits that avoiding this impact would have provide a rational for making the supply of environme...
An orthogonal dexamethasone-trimethoprim yeast three-hybrid system.

The yeast three-hybrid assay is an important tool for the detection of protein-ligand interactions in vivo and has recently been used successfully for the discovery of novel drug targets and the directed evolution of enzymes[1–6]. Schreiber and co-workers developed the first chemical inducer of dimerization (CID)3, a dimer of the immunosuppressant FK506[7]. Building from this work, a number of yeast three-hybrid systems based on different CIDs have been reported[2, 8]. We previously developed and optimized a three-hybrid system built around the small molecule CID dexamethasone-methotrexate (Dex-Mtx)[9–11]. The Dex and Mtx ligands were chosen because of their high affinities for their respective protein receptors, the rat glucocorticoid receptor and Escherichia coli dihydrofolate reductase, respectively[12, 13]. However, we hypothesized that the cross-reactivity of Mtx with endogenous DHFR in the yeast cells could impair transcription activation by Dex-Mtx in the yeast three-hybrid assay. In order to overcome this partial limitation we set out to design a CID that would selectively bind to E. coli DHFR and not to endogenous yeast DHFR. As an alternative to Mtx, we chose the DHFR inhibitor trimethoprim (TMP), which is known for its selectivity for bacterial forms of DHFR[14]. Studies have confirmed that while Mtx inhibits growth of wild type Saccrharomyces cerevisiae, TMP does not[15], suggesting that TMP could be a superior CID in yeast. Here we report the design, synthesis, and in vivo activity of Dex-TMP in the yeast three-hybrid assay. By analogy to our dexamethasone-methotrexate system, we chose to build a heterodimeric CID using the ligand-receptor pairs dexamethasone (Dex)-rat glucocorticoid receptor (GR) and trimethoprim (TMP)-E. coli dihydrofolate reductase (DHFR). Both Dex and TMP can be modified without disrupting receptor binding, making them suitable CIDs[16–18]. Both ligands are cell-permeable and commercially available. The ligand-receptor pair Dex-GR has a KD of 5 nM and has been used successfully in yeast three-hybrid systems[9]. E. coli dihydrofolate reductase (DHFR) has a KI of 1.3 nM for inhibition by TMP[14]. We anticipated that the two interactions would be sufficiently strong to induce protein dimerization and transcription activation in the yeast three-hybrid assay.
The effect of L-DOPA on Cryptococcus neoformans growth and gene expression.

Cryptococcus neoformans is unusual among melanotic fungi in that it requires an exogenous supply of precursor to synthesize melanin. C. neoformans melanizes during mammalian infection in a process that presumably uses host-supplied compounds such as catecholamines. L-3,4-dihydroxyphenylalanine (L-DOPA) is a natural catecholamine that is frequently used to induce melanization in C. neoformans and L-DOPA-melanized cryptococci manifest resistance to radiation, phagocytosis, detergents and heavy metals. Given that C. neoformans needs exogenous substrate for melanization one question in the field is the extent to which melanin-associated phenotypes reflect the presence of melanin or metabolic changes in response to substrates. In this study we analyze the response of C. neoformans to L-DOPA with respect to melanization, gene expression and metabolic incorporation. Increasing the concentration of L-DOPA promotes melanin formation up to concentrations > 1 mM, after which toxicity is apparent as manifested by red...
A Transient Technique for Measuring the Effective Thermal Conductivity of Saturated Porous Media With a Constant Boundary Heat Flux

An experimental technique for measuring the effective thermal conductivity of saturated porous media is presented. The experimental method is based on the transient heating of a semi-infinite cylinder by a constant heat flux at the boundary. The data reduction technique is unique because it avoids determining the effective thermal diffusivity and quantifying the boundary heat flux. The technique is used to measure the effective thermal conductivity of glass-water, glass-air, and steel-air systems. These systems yield solid-fluid conductivity ratios of 1.08, 25.7, and 2400, respectively. The solid phases consist of 3.96 mm glass spheres and 14 mm steel ball bearings, which give mean porosities of 0.365 and 0.403. In addition, particular attention is paid to assessing experimental uncertainty. Consequently, this study provides data with a degree of precision not typically found the literature.
Experience with 1000 fibergastroscopic examinations of the stomach.

1. One thousand patients had examinations of the stomach by Fiberscope and by X-ray and conventional gastroscope.
Partial nearest neighbor PDF for multi-component material systems

We develop general expressions for partial nearest neighbor probability density functions (PNNPDF’s) for equilibrium multi-component systems, valid for arbitrary partial densities, temperatures, and interaction potentials; thus providing an alternative means of describing structure at the microscopic (atomic scale) level for multi-component material systems. This paper thus complements an earlier paper (U.F. Edgal and D.L. Huber, J. Phys. Chem. B 108, 13777–13788 2004) in the analytical investigation of the classical statistical thermodynamics of multi-component systems. The connection between PNNPDF’s and the commonly employed partial m-body distribution functions is detailed. Results for PNNPDF’s and partial m-body distribution functions applicable for the poisson-distributed multi-component system and the low density binary mixture of hard spheres are provided. The statistical geometry of the systems is further studied through a brief investigation of particle clustering. A major hallmark of the above investigation involves the several multiple integrals and multiple sums encountered, that were quite formidable to perform, even in the absence of particle interactions.
Respiration rates and sugar accumulation in normal and moisture stressed Russet Burbank potatoes

Studies were made on Russet Burbank tubers grown under normal and moisture stressed conditions. Stressing the tubers caused increased reducing sugar accumulation in the basal end during storage. Respiration rates of apical and basal portions of stressed and normal tubers were followed during the growing season and in storage. Although its sugar content was greater, the basal end of stressed tubers respired at a significally slower rate than apical ends from the same tubers. Normal basal and apical portions showed no statistical differences in respiration although the apical end respired at a slightly faster rate than the basal end. A positive linear correlation between sugar concentration and respiration rate of the apical portion was obtained. Differences were found in the abilities of apical and basal ends to alter respiration rates in response to changes in sugar concentration. The resprationof the apical end was the more sensitive to increased sugar concentration. The basal end of stressed tubers lost some of its ability to respond, probably because of increased physiological aging caused by the stress conditions.
Solitary waves for power-law regularized long-wave equation and R ( m , n ) equation

This paper integrates the regularized long-wave equation with power-law nonlinearity using the solitary-wave ansatz. A few of the conserved quantities are calculated by using the 1-soliton solution. This technique is then extended to obtain the solitary-wave solution of the R(m,n) equation and a conserved quantity is also calculated for this generalized equation.
A Precision Laboratory Method for Determining the Mechanical Equivalent of Heat

An apparatus for determining the mechanical equivalent of heat by measuring the heat developed within a stationary copper cylinder as well as the torque developed by it when placed in a rotating magnetic field, is described. The field strength is made unvarying with angular position by the actual rotation of an electromagnet with slip rings. Radiation loss is reduced to a minimum by immersing the copper cylinder in water contained within a thermos bottle. In addition to the mechanical and heat energy measurements, the equivalent electrical energy is measured at the same time.
Decoding choice and mutual information on a moment-by-moment basis from single neurons in rat prefrontal cortex

Prefrontal cortex (PFC) neurons participate in representing a variety of stimuli, events, and processes that occur during the execution of behavioral tasks including spatial relationships as well as decision- and reward-related processes. We tested rats in a T-maze, delayed-alternation, decision-making task while simultaneously recording multiple single-unit spike trains from the prelimbic region of PFC. Animals were trained to navigate down the runway of the maze and choose one of two arms opposite to the one previously visited for food rewards. We used a recursive Bayesian approach to investigate the extent to which decision states could be decoded from the spike counts from neuronal ensembles in PFC at the time of decision-making. This approach estimates a full posterior probability distribution over states as a function of the spiking activity. We estimated the Bayesian model using a boot-strap particle filter [1]. The particle filter is useful because it provides a computationally tractable approximation of the spike-train and task-related state probability distributions without assumptions of linearity or being Gaussian. Particle filtering starts with a collection of particles, which can be thought of as a cloud of guesses of the task-related state xt. Importance weights Wt are then assigned to each guess according to how likely a neural event yt is, given the particular guess xt. By resampling we obtain a new set of particles that, in a certain sense, is consistent with the likelihood of generating yt from xt. Additionally, these resampled particles can be regarded as a draw from the approximate posterior probability distribution p(xt | yt-1) of task-related states. Calculating the expectation of the posterior probability distribution yields the point estimate of the state as the process iterates through time. To investigate the contribution of individual neurons to the decoding process, mutual information was calculated on a moment-by-moment basis between the state distribution and the neuron’s probability distribution of firing. The animal’s choice to turn left or right in order to obtain a reward was decoded during each trial based on training spike-train data from all other trials (leave-one-out cross-validation). For each neuron in the decoded ensemble, the history of spiking activity and its interaction with choice contributed to the spike-train probability model. The expected value calculated over 1000 binary particles of the filter diffused toward the observed behavioral choice in 85% and 76% of the trials of two animals. For trials where a behavioral error was observed (same arm choice on adjacent trials), the mutual information declined between the state distribution and spike train distribution indicating an increase in independence between task-related states and probability of neural firing. These results indicate that the particle filter accurately decoded the future behavioral choice of the animal during the pickup and delay intervals in two animals tested.
Design of an interactive spell checker: optimizing the list of offered words

Interactive spell checking is an instance of a general problem that is characterized by doubt as to the correctness of an input, and the need to correct the input or offer a set of possible corrections. Our contention is that a well-defined model can provide a basis to improve the performance of spell checkers and other similar applications such as voice recognition, historical document searches, and data imputation among others. In this paper, we introduce a model designed to help the spell checkers within word processors place the correct word at, or near, the top of the list of offered words. A prototype spell checker (SP) is developed based on the model. It is tested on documents typed by subjects and found to be very accurate.
Multiple personality disorder and the choice of self: Change factors in a brief therapy case

A person who identified herself as having a multiple personality disorder made remarkable changes after seven psychotherapeutic sessions and two batteries of tests, one on the alter. The case raises such problematic issues as the diagnosis of MPD, the unitary versus discrete theories and treatment of it, change factors in brief psychotherapy and for all psychotherapy, and the use of psychological tests.