cssi/SciSciGPT-SciSciNet huggingface dataset:
Comparison of biological and behavioral activities of alpha- and gamma-melanocyte stimulating hormones

The biological and behavioral activities of gamma-MSH ( ψ -MSH) and alpha-MSH ( α -MSH) were compared using three different tests: darkening of the skin of Anolis , grooming behavior of rats, and performance of a visual discrimination task by rats. When incubated with the Anolis skin, both peptides cause skin darkening. However, α -MSH is much more potent than ψ -MSH. The α -MSH effect is not antagonized by coincubation with ψ -MSH. When given intraventricularly to rats, α -MSH induces a marked grooming behavior. This effect was not noted upon administration of ψ -MSH. Injection of ψ -MSH with the α -MSH did not produce a grooming response significantly different from α -MSH alone. In the visual discrimination task, the two peptides had opposite effects on the rate at which rats learned the initial discrimination and a subsequent reversal. The peptides were injected intraperitoneally prior to behavioral testing. Following α -MSH, rats learned the discrimination and subsequent reversal faster than control rats. Following ψ -MSH, rats learned the initial discrimination at approximately the same rate as controls, and learned the reversal much slower. These results are discussed in terms of the similarity and differences in the mechanisms of action of α -MSH and ψ -MSH.
Anthropologies and Histories: Essays in Culture, History, and Political Economy

"Elegantly written essays...Roseberry is the real gem, an anthropologist with extensive Latin American field experience and an impressive scholarly grasp of the histories of anthropology and Marxist theory."--Micaela di Leonardo, The Nation "An extremely stimulating volume ...rich and provocative, and codifies a new depature point."--Choice "As a critic ...Roseberry writes with sustained force and clarity...his principal points emerge with a directness that will make this book attractive to a wide range of readers."--American Anthropologist "Roseberry in among the most astute, careful, and theoretically cogent of the anthropologists of his generation...[This book] illustrates well the breadth and coherence of his thinking and guides the reader through the complicated intersections of anthropology with history, political economy, Marxism, and Latin American studies."--Jane Schneider, CUNY In Anthropologies and Histories, William Roseberry explores some of the cultural and political implications of an anthropological political economy. In his view, too few of these implications have been explored by authors who dismiss the very possibility of a political economic understanding of culture. Within political economy, readers are offered sophisticated treatments of uneven development, but when authors turn to culture and politics, they place contradictory social experiences within simplistic class or epochal labels. Within cultural anthropology, history is often little more than new terrain for extending anthropological practice. Roseberry places culture and history in relation to each other, in the context of a reflection on the political economy of uneven development. In the first half of this books, he looks at and critiques a variety of anthropological understandings of culture, arguing for an approach that sees culture as socially constituted and socially constitutive. Beginning with a commentary on Clifford Geertz's seminal essay on the Balinese cockfight, Roseberry argues that Geertz and his followers pay insufficient attention to cultural differentiation, to social and political inequalities that affect actors' different understandings of the world, other people, and of themselves. Sufficient attention to such questions, Roseberry argues, requires a concern for political economy. In the second half of the book, Roseberry explores the assumptions and practices of political economy, indicates the kind of problems that should be central to such an approach, and reviews some of the inadequacies of anthropological studies. William Roseberry is a professor of anthropology at the New School for Social Research.
Large-aperture photoconducting antennas excited by high optical fluences

The saturation and power scaling of terahertz radiation produced by large-aperture photoconducting antennas under high electric fields and high optical fluences are described. From the saturation behavior, a large-aperture transmitter can be designed to produce the maximum pulse energy of terahertz radiation for a given photoconductor, optical pulse energy and electric field.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Characterization of telomeres and telomerase expression in Xiphophorus

Research investigating telomere lengths and telomerase expression in vertebrates has progressively become important due to the association of these two biological endpoints with cellular aging and cancer in humans. Studies that rely upon the traditional use of laboratory mice have been faced with limitations largely due to inbred mice possessing large telomeres and ubiquitous expression of telomerase. Recently, a number of small fish species have been shown to provide potentially informative models for examining the role of telomeres and telomerase within intact vertebrate animals. Xiphophorus fishes represent a new world live-bearing genus that has not previously been assessed for telomere length or telomerase expression. To add to the knowledge base of telomere and telomerase biology in vertebrates we assessed telomere length and telomerase expression among several species of Xiphophorus. The telomere lengths in several organs (gill, brain, eyes, testis, ovary and liver) in three species (Xiphophorus hellerii, Xiphophorus maculatus, Xiphophorus couchianus) and also in F(1) interspecies hybrids were approximately 2-6 kb. This size was consistent within the same organs of the same species, as well as between species and F(1) hybrids. Despite possessing relatively short telomere lengths compared to humans, the consistency of size among Xiphophorus species and organs may allow experimental detection of telomere shortening. The relative expression of telomerase reverse transcriptase (TERT) was determined by quantitative real-time PCR. Expression levels of TERT was measured in seven organs (ovary, testis, liver, gill, brain, heart, skin) from X. maculatus, X. hellerii and in control and ultraviolet light (UVB) exposed skin samples from X. maculatus, X. hellerii, and F(1) interspecies hybrids. TERT gene expression was significantly higher in ovary and testis, while all other organs showed low relative TERT expression. Detectable increases in TERT expression were found in skin samples upon UVB exposure. Our findings suggest that Xiphophorus may serve as a suitable model for future studies investigating the association of telomere length and telomerase expression in regard to aging and disease.
On Optimal Minimax Jamming and Detection of Radar Signals

A game between an intelligent jammer J and decision maker DM is considered. DM seeks to detect a coherent slowly fading narrowband signal under a Neyman-Pearson criterion. His observations are corrupted with additive narrowband noise, the source of which is J's jamming with a power constraint, but otherwise almost arbitrary statistics. DM knows J's action but the converse is not true. When the number of samples increases asymptotically, a minimax solution for the game exists where the jamming is Gaussian, independent of the desired signal amplitude level and probability distribution. The same result also holds for detection of a nonrandom baseband signal.
Comparison of xylans from several annual plants.

Abstract Hemicellulose A fractions from corn cobs, corn stalks, wheat straw, alfalfa and soybean stems, and sunflower stalks were isolated from both chlorite and chlorine-ethanolamine holocelluloses. Hemicellulose A fractions from chlorite holocelluloses were obtained in slightly lower yields than those from chlorine-ethanolamine holocelluloses. Hemicellulose A composition was essentially independent of the process for preparing holocellulose. Hemicellulose A from corn cob, corn stalk, and wheat straw contained d -glucuronic acid, l -arabinose, and d -xylose units in the ratios of 1:1:22, 1:2:39, and 1:3:43. Hemicellulose A from alfalfa and soybean stems and sunflower stalks had no arabinose and contained one uronic acid unit per each 10–14 d -xylose units. Evidence was obtained that the uronic acid in each hemicellulose was 4- O -methyl- d -glucuronic acid.
SIZE OF BANK, SIZE OF BORROWER, AND THE RATE OF INTEREST

I THE EVIDENCE THAT is available shows that interest rates charged on business loans by commercial banks tend to vary inversely with the size of the loan being made and therefore with the size of the borrower making the loan, since smaller borrowers tend to make smaller loans.' Several explanations have been offered of this fact that interest rates charged small borrowers tend to be greater than interest rates charged large borrowers. One explanation is that the costs of making loans to small borrowers tend to be greater than the costs of making loans to large borrowers. Many costs tend not to vary with the size of loans; consequently, costs as a percentage of loan value decrease with loan size and therefore with the size of the borrower. In addition, the absolute size of the costs of investigating credit worthiness may be greater for small borrowers than for large borrowers.2 A second explanation is that lenders ask larger risk premiums on loans to small borrowers than on loans to large borrowers, other things the same. Professor Alhadeff has proposed a third explanation of the fact that smaller borrowers appear to pay higher interest rates than larger borowers, and it is with this explanation that the present paper is concerned.3 Alhadeff recognizes that differential costs and, perhaps, differential risk premiums undoubtedly play a role,4 but he maintains that, to explain fully the higher rates charged small borrowers, one must consider ". . . the nature of the market in which large borrowers deal." Alhadeff takes as the starting point of his analysis the observed
Sa1678 Duodenal Stents Are Associated With More Durable Patency As Compared to Percutaneous Endoscopic Gastrojejunostomy in the Palliation of Malignant Gastric Outlet Obstruction

Background Gastroduodenal outlet obstruction (GOO) is a critical complication of cancers localized within and adjacent to the upper gastrointestinal tract. Approaches to the relief of GOO include surgical bypass with gastrojejunostomy (GJ), endoluminal placement of a self-expandable metallic stent (SEMS), and percutaneous endoscopic gastrostomy with jejunal extension (PEG-J). To date no studies have compared the outcome of utilizing PEG-J with other modalities of therapy. Objectives To determine if there is a difference in complications or effectiveness when survival and/or device patency of PEG-J is compared to that of gastroduodenal SEMS in patients with malignant GOO. Methods Patients who underwent placement of either PEG-J or gastroduodenal SEMS for unresectable malignant GOO were included in a retrospective cohort study. Results 24 patients (12 men) with a median age of 68.5 years underwent either PEG-J (n=12) or gastroduodenal SEMS (n=12) placement. Patients undergoing SEMS placement experienced longer overall device patency and/or survival as compared to those undergoing PEG-J (median 70 versus 35 days). Complications, including the need for re-intervention, were similar among both groups. Patients who underwent PEG-J as compared to those that had SEMS placement had a hazard ratio of 3.85 (CI 1.28-11.11) for decreased overall survival. Conclusion In patients with malignant GOO, placement of a palliative SEMS for gastric decompression and nutrition was associated with longer aggregate device patency and survival as compared to PEG-J. Both modalities were similar with respect to complications and the need for re-intervention.
CREATION OF ATRIAL SEPTAL DEFECTS BY BALLOON CATHETER IN BABIES WITH TRANSPOSITION OF THE GREAT ARTERIES

Abstract Most babies born with transposition of the great arteries have circulations that are barely compatible with extrauterine life; and few will survive long enough for planned surgical redirection of venous return without palliative operative treatment. Operations, however, carry a high mortality-rate in small deeply cyanosed infants, and the creation of an atrial septal defect using a balloon filled with angiocardiographic contrast medium at the end of a cardiac catheter has been found to be a safe and effective method that is life-saving in such babies. Our experience, coupled with the knowledge of more than a hundred cases, 80-85% of which have been successful, suggests that if the procedure were widely adopted in the newborn, transposition of the great arteries might soon become as common as Fallot's tetralogy amongst children attending cardiac clinics.
Scanning force microscopy of polyimide surfaces

Abstract Scanning force microscopy was used to study several polyimide surfaces. The effects of r.f.-sputtering in argon and nitrogen atmospheres on the surface morphology of poly-[4,4′-oxydiphenylenepyromellitimide] (PMDA-ODA) and the polyimide (PI) based on the monomers 3,3′,4,4′-biphenyl tetracarboxylic dianhydride (BPDA) and p-phenylene diamine (PDA) were investigated. PI surfaces treated with r.f.-sputtering in nitrogen exhibited morphological features due to redeposited metal from the walls of the sputtering chamber, while no significant morphological change was observed when an argon atmosphere was used, for the same duration of sputtering treatment. It was shown that the enhancement of adhesion of metals on PI surfaces that have been treated with r.f.-sputtering in Ar, is not due to mechanical interlocking but rather due to chemical modification of the surface. The effect of different heat treatments on the surface morphology of co-deposited films of oxydipthalic dianhydride (ODPA) and 1,3-bis-[3-aminophenoxyl] benzene (APB), prepared by molecular beam deposition (MBD), was also studied. Such MBD films exhibited a strong dependence of morphology on the annealing process and environment.
SNP interaction detection with Random Forests in high-dimensional genetic data

Identifying variants associated with complex human traits in high-dimensional data is a central goal of genome-wide association studies. However, complicated etiologies such as gene-gene interactions are ignored by the univariate analysis usually applied in these studies. Random Forests (RF) are a popular data-mining technique that can accommodate a large number of predictor variables and allow for complex models with interactions. RF analysis produces measures of variable importance that can be used to rank the predictor variables. Thus, single nucleotide polymorphism (SNP) analysis using RFs is gaining popularity as a potential filter approach that considers interactions in high-dimensional data. However, the impact of data dimensionality on the power of RF to identify interactions has not been thoroughly explored. We investigate the ability of rankings from variable importance measures to detect gene-gene interaction effects and their potential effectiveness as filters compared to p-values from univariate logistic regression, particularly as the data becomes increasingly high-dimensional. RF effectively identifies interactions in low dimensional data. As the total number of predictor variables increases, probability of detection declines more rapidly for interacting SNPs than for non-interacting SNPs, indicating that in high-dimensional data the RF variable importance measures are capturing marginal effects rather than capturing the effects of interactions. While RF remains a promising data-mining technique that extends univariate methods to condition on multiple variables simultaneously, RF variable importance measures fail to detect interaction effects in high-dimensional data in the absence of a strong marginal component, and therefore may not be useful as a filter technique that allows for interaction effects in genome-wide data.
The effect of structure on diffusion and reaction in immobilized cell systems

Abstract The behavior of many heterogeneous systems in technology and in nature relies upon the relative rates of molecular diffusion and reaction in structures containing inhomogeneous distributions of reactive sites. In this study, Monte Carlo simulations are used to calculate rate constants for particle diffusion and reaction in immobilized cell systems as a function of cell reactivities, particle diffusivities in the cells and matrix, and spatial arrangement of cells. A variety of conditions are examined, ranging from instantaneous reactions to slow reaction cases. For highly reactive (diffusion-limited) conditions, spatially homogeneous distributions of cells exhibit the largest rate constants. An increase in the heterogeneity of the cell distribution dramatically decreases the rate constants. However, for conditions of low reactivity (reaction-limited), homogeneous and heterogeneous distributions of cells yield similar rate constants. The molecular diffusivity inside a cell can also influence the rate constant by altering the molecule residence time inside a cell; rate constants increase as diffusivities decrease.
Mechanism of AMPA Receptor Activation by Partial Agonists: DISULFIDE TRAPPING OF CLOSED LOBE CONFORMATIONS*

The mechanism by which agonist binding to an ionotropic glutamate receptor leads to channel opening is a central issue in molecular neurobiology. Partial agonists are useful tools for studying the activation mechanism because they produce full channel activation with lower probability than full agonists. Structural transitions that determine the efficacy of partial agonists can provide information on the trigger that begins the channel-opening process. The ligand-binding domain of AMPA receptors is a bilobed structure, and the closure of the lobes is associated with channel activation. One possibility is that partial agonists sterically block full lobe closure but that partial degrees of closure trigger the channel with a lower probability. Alternatively, full lobe closure may be required for activation, and the stability of the fully closed state could determine efficacy with the fully closed state having a lower stability when bound to partial relative to full agonists. Disulfide-trapping experiments demonstrated that even extremely low efficacy ligands such as 6-cyano-7-nitroquinoxaline-2,3-dione can produce a full lobe closure, presumably with low probability. The results are consistent the hypothesis that the efficacy is determined at least in part by the stability of the state in which the lobes are fully closed.
Idiopathic Pulmonary Hemosiderosis: An Electron Microscopic and Immunofluorescen

Electron microscopic and immunofluorescent studies are reported in a patient with idiopathic pulmonary hemosiderosis, suggesting that idiopathic pulmonary hemosiderosis is distinct from other pulmonary hemorrhagic syndromes associated with antibasement membrane antibody or immune complex mediated diseases. The ultrastructural studies showed evidence of nonspecific lung injury and indirect evidence of vascular lesions. No subendothelial deposits or basement membrane lesions were seen. Immunofluorescent studies failed to reveal any evidence for localization of IgG, IgM, s lC, Clq or fibrinogen in the lung. Investigation of platelet function showed low and low normal values of platelet retention on a glass bead column, but findings were otherwise normal.
Metal-cavity nanolasers

We demonstrated the operation of metal-cavity microlasers and nanoLEDs flip-chip bonded to silicon under electrical injection at room temperature. The work represents significant progress bridging the gap between nanophotonics and silicon electronics.
38‐Amino acid form of pituitary adenylate cyclase activating peptide induces process outgrowth in human neuroblastoma cells

Permanent cell lines from human neuroblastoma, a sympathoadrenal malignancy, are known to exhibit a more neuronal phenotype characterized by outgrowth of long processes in response to multiple second messenger analogs. In this report we demonstrate that the 38-amino acid form of a peptide homologous to vasoactive intestinal peptide (VIP), pituitary adenylate cyclase activating peptide (PACAP), as well as the 27-amino acid form of PACAP, induce NB-OK human neuroblastoma cells to extrude cellular processes within 5 hr of treatment with either peptide at 10−8 M. Treatment of NB-OK cells with PACAP38 or PACAP27 at 10−8 M for 1 hr also elevates cAMP content greater than 100-fold and inositol lipid turnover 11- to 12-fold. VIP acutely induces process outgrowth and elevates intracellular second messenger levels in NB-OK cells only at higher concentrations, 10−6 M or greater. In contrast to the equipotency of PACAP27 and PACAP38 in stimulating the outgrowth of processes observed after 5 hr of treatment, PACAP38 is much more potent than PACAP27 when NB-OK cells are scored for process outgrowth after 72 hr of treatment. Correlating with the extended time course over which morphologic changes are seen with PACAP38, cAMP levels remain elevated for a more prolonged time span during treatment with PACAP38 than PACAP27. After 72 hr of treatment with PACAP38 versus treatment with PACAP27, cAMP levels are elevated 10-fold versus 3-fold, respectively. PACAP38 at 10−8 M also induces process outgrowth in two additional human neuroblastoma lines tested, SMS-KAN and LA-N-1, whereas PACAP27 and VIP at the same concentration are less effective. The effects of PACAP38 on neuroblastoma cells may be a model for neurotrophic activities of PACAP38 via G protein-linked intracellular messengers in human sympathoadrenal cells. © 1993 Wiley-Liss, Inc.
Hdmx Modulates the Outcome of P53 Activation in Human Tumor Cells

Tumors that express wild-type P53 provide a target for therapies designed to reactivate P53 function. This is supported by the potent activation of P53 in tumor cells by Nutlin, a cis-imidazoline that inhibits the Hdm2-P53 interaction. The efficacy of Hdm2·P53 antagonists could be compromised if they do not antagonize Hdmx, an Hdm2 homolog that inhibits P53 transactivation. We evaluated the role of Hdmx expression in sensitivity to Nutlin in a range of cancer cell lines. Nutlin reduced Hdmx levels in normal cells and some cancer cell lines, whereas other cancer cells were refractory to such down-regulation. Strikingly, Nutlin did not disrupt Hdmx·P53 complexes, and in cell lines where no Hdmx degradation occurred, Nutlin failed to induce apoptosis. shRNA-mediated reduction of Hdmx sensitized cells to apoptosis, but caspase-3 was neither required nor sufficient for Hdmx degradation or apoptosis. Our data imply that Hdmx is an important determinant of the outcome of P53 activation. Thus, targeting Hdmx may be a therapeutic strategy that complements drugs such as Nutlin.
Influence of DNA-dye complex stability on separation resolution in microchip electrophoresis.

Background: Different markers have been used to label DNA for sample detection in gel electrophoresis. Intercalating dyes, (e.g., YOYO) have been widely used to label DNA for sample detection, because they do not require the use of radioisotopes, covalent attachment or enzyme reactions. The labeling of DNA fragments can be achieved by simply mixing solutions of the intercalating dye and DNA sample. However, the separation quality of DNA labeled with intercalating dyes is greatly influenced by the buffer used, which affects the DNA–dye complex stability. Results: In this study, we investigated the effects of DNA–dye complex stability on separation resolution of dsDNA migrating in a photopolymerized polyacrylamide gel by measuring mobility and dispersion coefficients on a microfluidic chip and comparing predicted separation resolution under different dye and buffer conditions. Conclusion: We found that a buffer containing tetrapentylammonium (NPe4 +) yielded better separation resolution than the frequently ...
Scattering of light by disordered spherulites. II. Effect of disorder in the magnitude of the anisotropy

The contribution to the disorder scattering by imperfect spherulites resulting from fluctuations in the magnitude of the anisotropy is analyzed for two-dimensional spherulites. The fluctuations are described in terms of a parameter characterizing the meansquare amplitude of the fluctuation and a correlation function describing the distance over which the correlation occurs. Cases considered are those where the correlation depends on either the radial or the angular separation of the scattering volume elements. As with the case of disorder in orientation, one finds that disorder in anisotropy may result in a nonzero value of intensity at μ = 0° and 90°, a decrease in the higher-order variation of scattered intensity with θ, and an increase in the intensity of scattering at higher values of θ over that for a perfect spherulite. In addition, disorder in the angular direction leads to an increase in the scattered intensity at small values of θ as compared with the zero intensity of scattering from a perfect spherulite at θ = 0°.
Comparative increases in utilization rates of ultrasound examinations among radiologists, cardiologists, and other physicians from 1993 to 2001.

Abstract Purpose To ascertain changes in the utilization rates of diagnostic ultrasound among radiologists, cardiologists, and other physicians in recent years. Methods and materials The nationwide Medicare Part B databases for 1993 and 2001 were searched in all ultrasound Current Procedural Terminology 4 codes, except for ophthalmic ultrasound and supervision and interpretation codes. Ultrasound examinations were categorized as general, vascular, breast, obstetric (very low in the Medicare population), and echocardiography. Using the Medicare physician specialty codes, utilization rates per thousand Medicare beneficiaries per year were calculated for radiologists, cardiologists, and other physicians for all codes in the five aforementioned categories. Results Radiologists performed 24% of all ultrasound examinations in 2001. The overall utilization rate of ultrasound examinations among radiologists increased from 132.9 per thousand Medicare beneficiaries in 1993 to 166.3 in 2001, a 25% increase. Among cardiologists, the rate increased from 190.3 in 1993 to 356.1 in 2001, an 87% increase. The vast bulk of these examinations were echocardiograms, but cardiologists also had some involvement in vascular ultrasound. Among other physicians, the rate increased from 116.9 in 1993 to 167.0 in 2001, a 43% increase. The areas of greatest involvement by these other physicians were echocardiography, vascular ultrasound, and general ultrasound. Of the five ultrasound categories, echocardiography had by far the highest volume. Conclusion Nonradiologist physicians utilize ultrasound at much higher rates than radiologists, primarily reflecting the influence of echocardiography. Between 1993 and 2001, the ultrasound utilization rate grew over 3 times as rapidly among cardiologists as among radiologists; the rate among other physicians grew almost twice as rapidly as it did among radiologists. This raises the concern that self-referral may be leading to higher utilization and costs.
Mechanisms of Shear-Induced Solid-State Reactions

Both experiments and band-structure calculations indicate that shear strains lead to closure of energy band gaps in periodic solids, and closure of the LUMO-HOMO gaps in molecules (this is also expected for non-metallic glasses). It allows athermal and ultrafast mechano-chemical reactions to occur. Simple models account for the phenomena. For periodic solids, shear shortens one axis and extends another. In contrast, hydrostatic compression causes both axes to contract. Thus the former shifts the band gaps oppositely for the two directions, causing a reduction in the minimum gap. For molecules, shear tends to increase the bonding orbitals while decreasing the antibonding orbitals, thereby reducing the LUMO-HOMO gaps. The models are consistent with band structure models for diamond. Shear-induced gap reductions account for the athermal chemical reactions observed by Bridgman, Enikolopyan, Boldyrev, and others. They account for the ultra-fast reactions that occur in explosives.
Workplace learning through peer groups in medical school clerkships

Purpose : When medical students move from the classroom into clinical practice environments, their roles and learning challenges shift dramatically from a formal curricular approach to a workplace learning model. Continuity among peers during clinical clerkships may play an important role in this different mode of learning. We explored students’ perceptions about how they achieved workplace learning in the context of intentionally formed or ad hoc peer groups. Method : We invited students in clerkship program models with continuity (CMCs) and in traditional block clerkships (BCs) to complete a survey about peer relationships with open-ended questions based on a workplace learning framework, including themes of workplace-based relationships, the nature of work practices, and selection of tasks and activities. We conducted qualitative content analysis to characterize students’ experiences. Results : In both BCs and CMCs, peer groups provided rich resources, including anticipatory guidance about clinical expectations of students, best practices in interacting with patients and supervisors, helpful advice in transitioning between rotations, and information about implicit rules of clerkships. Students also used each other as benchmarks for gauging strengths and deficits in their own knowledge and skills. Conclusions : Students achieve many aspects of workplace learning in clerkships through formal or informal workplace-based peer groups. In these groups, peers provide accessible, real-time, and relevant resources to help each other navigate transitions, clarify roles and tasks, manage interpersonal challenges, and decrease isolation. Medical schools can support effective workplace learning for medical students by incorporating continuity with peers in the main clinical clerkship year. Keywords: clinical education; workplace learning; peer continuity (Published: 25 November 2014) Citation: Med Educ Online 2014, 19 : 25809 - http://dx.doi.org/10.3402/meo.v19.25809
Transient scattering of a beam from a periodic surface

Transient scattering from a periodic surface has been examined for an incident plane wave. For this plane wave case the authors used a number of techniques to determine the scattered fields. One such technique, known as the Rayleigh hypothesis, is only valid for sufficiently smooth surfaces. A more encompassing integral equation theory was also developed to provide solutions for rougher surfaces. These two methods can be modified to a more general nonuniform (beam) incidence wave, by properly choosing a number of plane waves, with which the resulting sum of plane waves can be formed into a beam. There are a number of ways in which the plane waves to be used can be determined. One method is to Fourier synthesize the plane waves needed to create a predetermined aperture field, this method is similar to antenna array beam synthesis. Another method, although less general, is to simply create a square wave using Fourier techniques which could then be space windowed to create the effect of a single beam. Both methods would ideally involve an infinite number a plane waves to exactly reconstruct the intended pattern, therefore a feasible solution would involve a finite number of plane waves, with the smallest number of plane waves needed to accurately create the beam as an optimal choice. By setting this limitation a slightly imperfect beam is expected, in fact the aperture field method will create a periodic beam (square-like), which will also need to be space windowed, and the two methods somewhat degrade into one.
Evaluating the monophyly of Eulimnadia and the Limnadiinae (Branchiopoda: Spinicaudata) using DNA sequences

The evolutionary relationships among the six nominal genera within the spinicaudate clam shrimp family Limnadiidae, as well as the validity of the limnadiid genus Eulimnadia, have been much debated in the literature with little consensus emerging. The lack of resolution on these topics impedes evaluations of limnadiid biodiversity, phylogeny, and character evolution. To address these issues, we used Bayesian and parsimony methods to analyze DNA sequences from three genetic loci (28S, 12S, cytb) that were obtained from representatives of five nominal limnadiid genera and one undescribed limnadiid species. These analyses confirm the monophyly of Eulimnadia and the most taxonomically inclusive phylogenetic analysis (28S) produces the following tree topology: (((((Eulimnadia, Metalimnadia), undescribed limnadiid), Imnadia), Limnadopsis), Limnadia). This topology is inconsistent with prior estimates of limnadiid inter-generic relationships. Maximum likelihood-based constraint analyses demonstrate that the above topology is significantly better than prior hypotheses of limnadiid relationships, and support the monophyly of Eulimnadia. Morphological character optimization on this topology suggests that the postulated close relationship between Limnadia and Eulimnadia is based on shared ancestral characteristics rather than synapomorphies. Furthermore, the discovery of the genetically distinct undescribed limnadiid lineage strongly supports the necessity of efforts to better evaluate limnadiid biodiversity, especially those in poorly collected zoogeographic regions.
A minute to learn and a lifetime to master: Implications of the poker craze for college campuses

This chapter explores the proliferation of poker (both live and online) and discusses how campuses have responded to this activity. The chapter concludes with some implications for practice and further research.
Cardiac troponin I concentrations following medetomidine‐butorphanol sedation in dogs

Abstract Objective To evaluate the effect of medetomidine–butorphanol sedation on serum cardiac troponin I (cTnI) concentration, a marker of myocardial ischemia and injury, in healthy dogs undergoing pre–surgical radiographs for orthopedic procedures. Study design Prospective clinical study. Animals Twenty client–owned dogs with no history of cardiac disease. Methods Dogs were evaluated for pre–existing cardiac disease with electrocardiogram (ECG), noninvasive blood pressure and echocardiogram. Sedation was achieved using a combination of medetomidine (10 μg kg−1) and butorphanol (0.2 mg kg−1) intravenously. Blood pressure, heart rate and ECG were serially recorded throughout the duration of sedation. Serum cTnI concentration was measured at baseline and 6, 18, and 24–hours post–sedation. Results Following administration of medetomidine and butorphanol, all dogs were adequately sedated for radiographs and had a decreased heart rate and increased diastolic blood pressure. Arrhythmias associated with increased parasympathetic tone occurred, including a sinus arrhythmia further characterized as a sinus bigeminy in 17 of the dogs. Serum cTnI was undetectable at all time points in all but three dogs. Two of the three dogs had a detectable concentration of cTnI at all time points measured, including prior to sedation. Only one of the two dogs had a cTnI concentration above the normal reference interval. The dogs that exhibited detectable cTnI had no significant difference in signalment, heart rate, blood pressure, or lactate concentration as compared to those with undetectable cTnI. Conclusions and clinical relevance Sedation with medetomidine and butorphanol had predictable cardiovascular effects including bradycardia, an increase in arterial blood pressure, and arrhythmias in apparently healthy dogs requiring radiographs for orthopedic injuries, but did not induce significant increases in serum cTnI concentration following the drug doses used in this study.
Impact of microRNA regulation on variation in human gene expression

MicroRNAs (miRNAs) are endogenously expressed small RNAs that regulate expression of mRNAs at the post-transcriptional level. The consequence of miRNA regulation is hypothesized to reduce the expression variation of target genes. However, it is possible that mutations in miRNAs and target sites cause rewiring of the miRNA regulatory networks resulting in increased variation in gene expression. By examining variation in gene expression patterns in human populations and between human and other primate species, we find that miRNAs have stabilized expression of a small number of target genes during primate evolution. Compared with genes not regulated by miRNAs, however, genes regulated by miRNAs overall have higher expression variation at the population level, and they display greater variation in expression among human ethnic groups or between human and other primate species. By integrating expression data with genotypes determined in the HapMap 3 and the 1000 Genomes Projects, we found that expression variation in miRNAs, genetic variants in miRNA loci, and mutations in miRNA target sites are important sources of elevated expression variation of miRNA target genes. A reasonable case can be made that natural selection is driving this pattern of variation.
Machine learning-based volume diagnosis

In this paper, a novel diagnosis method is proposed. The proposed technique uses machine learning techniques instead of traditional cause-effect and/or effect-cause analysis. The proposed technique has several advantages over traditional diagnosis methods, especially for volume diagnosis. In the proposed method, since the time consuming diagnosis process is reduced to merely evaluating several decision functions, run time complexity is much lower than traditional diagnosis methods. The proposed technique can provide not only high resolution diagnosis but also statistical data by classifying defective chips according to locations of their defects. Even with highly compressed output responses, the proposed diagnosis technique can correctly locate defect locations for most defective chips. The proposed technique correctly located defects for more than 90 % (86 %) defective chips at 50× (100×) output compaction. Run time for diagnosing a single simulated defect chip was only tens of milli-seconds.
Surgical resection for lung cancer in the octogenarian

Background: As the US population ages, clinicians are increasingly confronted with octogenarians with resectable non-small cell lung cancer. Earlier reports documented substantial risk for surgical resection in this age group. Methods: We reviewed our surgical experience in octogenarians who underwent curative resection from 1990 to 2003. Results: Sixty-one patients underwent resection: 46 lobectomies, 6 segmentectomies, 5 wedge resections, and 4 pneumonectomies. There was one perioperative death (1.6%). The overall complication rate was 38% with a major complication rate of 13%. The average postoperative length of stay was 7 days. Overall 5-year survival was 38%, and 82% for stage IA patients. Patients with more advanced disease had a significantly worse survival. Conclusions: Appropriately selected octogenarians with early stage disease should be offered anatomic surgical resection for cure. These patients can anticipate a long-term survival, and should not be denied an operation on the basis of age alone.
Macroeconomic Policies And Economic Growth: The Case Of Costa Rica

Applying the well-known GARCH/ARCH (Engle, 1982, 2001) model, we find that real output in Costa Rica is positively affected by real M2 money, the expected inflation rate, and the U.S. output and negatively influenced by the depreciation of the colon. Consistent with the Barro-Ricardo (1989) hypothesis, deficit spending does not affect real output. Therefore, the Costa Rican government may need to pursue a balanced budget and maintain the stability of the colon because the costs of currency depreciation outweigh the benefits.
Ultrafast Material Science Probed Using Coherent X-ray Pulses from High-Harmonic Generation

X-rays represent one of the most powerful tools for understanding materials at the nanoscale, uncovering important information related to magnetism, photochemistry, materials, biology, nanoscience and many other areas of science and technology. The recent availability of ultrashort x-ray pulses paves the way for a completely new generation of experiments that can capture the coupled dynamics of elementary excitations in materials. Ultrashort x-ray pulses can access the fundamental interactions between charge, lattice, orbital, and spin dynamics in real time, which eventually determine the intrinsic physical limits at which, for example, a phase-transition in a correlated-electron material occurs, the magnetic state of a material can be switched, or a chemical reaction on a surface evolves. The goal of this chapter is to review recent breakthroughs in using ultrashort x-ray pulses from high-harmonic generation for the study of ultrafast material science.
The Master Teacher Program: Professional Development for College Teachers

In this qualitative study I explored six college (CEGEP) teachers’ perspectives on teaching and learning over a two-year period, as they completed the first four courses in a professional development program, the Master Teacher Program (MTP). Repeated, semi-structured interviews were analyzed, using the complementary processes of categorizing and connecting. Results revealed, through four patterns and three major dimensions, a process of evolution from a teacher- to a learner-centered perspective.
The Math and Science Engagement Scales: Scale development, validation, and psychometric properties

Abstract There is an urgent need to develop appropriate instruments to measure student engagement in math and science for the fields of research and practice. The present study developed and validated student- and teacher-report survey measures of student engagement in math and science. The measures are built around a multidimensional perspective of engagement by using a bifactor modeling approach. The sample was recruited from an ethnically and socioeconomically diverse middle and high school student population in the United States. The findings confirmed that student engagement is comprised of multiple related yet distinct dimensions, with evidence to support a bifactor structural model. There was also empirical evidence supporting measurement invariance and predictive validity. The results demonstrate the soundness of the psychometric properties of the Math and Science Engagement Scales.
The NPM Agenda for Service Delivery: a Suitable Model for Developing Countries?

The Internationalization of Public Management constitutes one of the first attempts to examine the conceptual and practical problems which attend such policy transfers, and to make preliminary judgements about the successes and failures of public management reform in developing countries. The distinguished group of contributors offers instructive insights into the complex reality of the development state.
Analytics of Decision Making

WHEN analyzing economic decision making in the classroom and elsewhere, it is common to assume that a decision maker has perfect knowledge and thus to argue as if he knows what the outcome of a decision will be in advance. Davis [13] suggests that such an assumption was implicitly contained in most early formulations of decision problems as they were generally posed as problems of choosing well between alternatives on the basis of one known situation. Use of such simplifying assumptions and their associated specifications is proper when the problem is essentially one of decision making under certainty [5] [6]. Unfortunately, however, we find that most of the observable situations of actual decision making and the presumed experimental conditions which represent the data generating processes and underlie much of our economic analysis, in general fall in the decision making under risk or uncertainty classes. This is but one of many problems encountered when attempting to apply existing theories in empirical investigation and reemphasizes our need for a comprehensive theory of economic behavior under uncertainty [5]. Luce and Raiffa [6] indicate that the bulk of formal theory in economics, psychology, and management sciences fall in the certainty class. They state, "Typically decision making under certainty boils down to this: Given a set of possible acts (the problem is) to choose one or all of those which maximize (or minimize) some given index.... Very often the heart of the problem is the appropriate choice of the associated index." Hildreth [5] suggests that certainty problems are trivial as far as the central issues of decision theory are concerned. We still do not have a unique and generally comprehensive decision theory, however, the past two decades has witnessed a rapidly growing literature which deals with various aspects of the problem as illustrated by Edwards [4], Machol [7] [8], Savage [10], and Hildreth [5] to name a few. While investigations have emphasized different dimensions of the problem, most have formulated the fundamental decision problem as one of choice among alternative courses of action where the consequence of any act depends upon a "state of the world" but where the likelihood of possible states is uncertain. Hildreth's outline about the constituent parts of decision problems is basically similar to that of others and can
A Case of Elephantiasis Neuromatosa

Elephantiasis neuromatosa is an uncommon disease characterized by large, grotesque tumorous skin hypertrophy. Recentry we experienced a case of this disease.Case: N. Y. 12-year-old girl. At birth she had a large pigmentation in the left thigh, which grew up gradually with skin hypertrophy like an elephant's skin. A tumor in the left inguinal region was noticed at 5 or 6 years old. Her mother has also many neurofibromas and a large pendulous tumor.Pathological examinations of the tumor and the skin revealed a typical plexiform neurofibroma.
Suppression of Unsteady Boundary-Layer Separation Using Sub-Optimal Control

A two-dimensional channel with localized suction from the upper surface is considered as a framework within which to consider sub-optimal control of an unsteady separating boundary layer. A quasi-steady (sub-optimal) approach is adopted in which the control input is optimized at each time as the unsteady ow evolves. Two cost functionals are implemented and compared; they both use a boundary-based performance measure that minimizes the dierence between the wall shear stress and a target distribution corresponding to the unseparated boundary layer. The two control mechanisms considered, with corresponding penalty functions in the respective cost functionals, are a domain-based control, involving a body force throughout the boundary layer, and a boundary-based control, involving the normal wall velocity. Both control mechanisms are successful in eliminating unsteady separation, and the relative eectiveness of each approach is compared.
Standards and Methods for the Evaluation of Hyperspectral Imaging System Performance

Hyperspectral imaging is being adopted for a wide range of applications including those related to industrial and manufacturing processes. The ability to spectrally discriminate differences between materials depends on a wide range of variables in the imaging system. Evaluating the performance of the system allows for the estimation of the probability of detection and false alarm rates. The performance of the hyperspectral imaging system can often be tied directly to costs, safety, and quality. This talk will cover both basic standards (such as reference diffusers and wavelength standards) and advanced methods (including microscene generation and the NIST Hyperspectral Image Projector) that can facilitate how well a hyperspectral imaging system performs. Article not available.