cssi/SciSciGPT-SciSciNet huggingface dataset:
Floor Fight: Protecting the Presidential Nomination Process from Last-Minute Manipulation of the Rules for National Party Conventions

The Democratic and Republican parties select their presidential nominees through a complex process stitched together from various disparate components that coalesce in a national party convention. Delegates to each party's national convention are typically chosen at state and local conventions or through other intra-party mechanisms. Most of those delegates are bound or pledged to a particular presidential candidate, at least for the initial rounds of voting at the national convention, based on the results of presidential preference primaries and caucuses throughout the nation. The rules of the national convention, however, are not determined until after all the delegates are selected and the presidential preference contests concluded. The delegates themselves have ultimate power to decide potentially dispositive issues such as how their votes will be counted, whether their binding or pledges are enforceable, and even the percentage of votes a candidate must receive to win. Allowing national convention delegates to adopt, amend, or suspend the rules governing the convention allows them to effectively nullify the millions of votes cast in presidential preference contests, undermining the legitimacy of the nomination process. Fundamental fairness and due process dictate that the rules governing the presidential nomination process should be determined at the outset, and not subject to change based on the political preferences of the delegates or which presidential candidates will benefit. Allowing such last-minute manipulation of the rules also fosters discord and intrigue within a political party at the very time it should be coalescing around a presidential candidate. This piece is a chapter of a forthcoming book on reforming the presidential nomination process. It begins by explaining the various components of the process. It then analyzes the national convention rules most susceptible to last-minute manipulation that could directly impact the party's nomination, such as the unit rule and two-thirds rule. Finally, it concludes by exploring case studies of conventions in which delegates and other party leaders engaged in eleventh hour machinations to swing the nomination to their preferred candidate. It focuses on the nominations of James K. Polk at the Democratic National Convention of 1844, James Garfield at the Republican National Convention of 1880, Hubert Humphrey at the Democratic National Convention of 1968, and Jimmy Carter at the Democratic National Convention of 1980.
Endoscopic cyst gastrostomy for traumatic pancreatic pseudocysts in children: a case series.

Background Pancreatic pseudocysts may develop after high-grade pancreatic injuries in children. Many resolve without intervention, and the management of symptomatic pseudocysts that persist remains controversial, with various open, percutaneous and laparoscopic approaches to intervention described. Successful endoscopic cyst gastrostomy has been reported in children with pancreatic pseudocysts of mixed etiology. Methods The trauma registry and electronic medical record of a level 1 pediatric trauma center were queried for children with a symptomatic pseudocyst following pancreatic trauma over a 12-year period, from 2008 to 2019. Results We describe a case series of five consecutive children with persistent symptomatic pancreatic pseudocysts following blunt abdominal trauma all successfully treated with endoscopic cyst gastrostomy. Discussion Endoscopic cyst gastrostomy appears to be safe and effective in the management of symptomatic pancreatic pseudocysts in children following pancreatic trauma. Level of evidence 5 – retrospective case series.
WIP: An exploration into the muddiest points and self-efficacy of students in introductory computer science courses

This work-in-progress (WIP) paper in the research track explored the muddiest point and self-efficacy for students in introductory computer science courses, starting with one course at a southern public institution. With the increasing demand in computing-related careers, the increased enrollments in undergraduate computer science courses are facing challenges to ensure the average passing rate. In this work, we applied the muddiest point to capture student’s perceptions of concepts of difficulty and used self-efficacy to better contextualize students’ perfections of self-efficacy in relation to concepts of difficulty. In this paper we present the results of one section of one introductory computing course, that revealed the perceived difficult topics as well as changes in self-efficacy throughout the semester. Furthermore, a positive correlation was found between self-efficacy and performance. Keywords: self-efficacy, muddiest points, student performance, computer science education
Just as Fragile as a Patient

The American hospital has evolved greatly over the past 100 years, from the almshouse once visited mainly by the desolate and poor as a last resort to that enigmatic, cutting edge institution which today forms the foundation of modern American health care. Advances in technology and medical science have transformed what were once terminal illnesses into minor health inconveniences, with the real battles against serious health threats typically occurring inside the four walls of a patient’s local hospital. The modern hospital has become such a beacon of hope that in 1986 Congress passed laws granting nearly everyone an unrestricted entitlement to emergency medical treatment at most acute care facilities.
Expanding evolutionary neuroscience: insights from comparing variation in behavior

Neuroscientists have long studied species with convenient biological features to discover how behavior emerges from conserved molecular, neural, and circuit level processes. With the advent of new tools, from viral vectors and gene editing to automated behavioral analyses, there has been a recent wave of interest in developing new, "nontraditional" model species. Here, we advocate for a complementary approach to model species development, that is, model clade development, as a way to integrate an evolutionary comparative approach with neurobiological and behavioral experiments. Capitalizing on natural behavioral variation in and investing in experimental tools for model clades will be a valuable strategy for the next generation of neuroscience discovery.
Policy Sociology in the Contemporary Global Era: Continued Importance and Pressing Methodological Considerations:

The intensities of the contemporary moment continue to prompt reflections on the strengths and limitations of approaches typically used to study education policy reform. The central contention of t...
The Education of the Prof: A Work in Progress

This article explores a return to litigation in legal services while on sabbatical and explores the cases handled during this time. The article continues on to discuss the rules of litigation preparation and the case theme. The article concludes with a discussion on how lawyers must educate the judiciary on new rules.
The Intensive Margin in Trade

Is the variation in bilateral trade flows across countries primarily due to differences in the number of exporting firms (the extensive margin) or in the average size of an exporter (the intensive margin)? And how does this affect the estimation and quantitative implications of the Melitz (2003) trade model? The benchmark Melitz model with Pareto-distributed firm productivity and fixed costs of exporting, predicts that, conditional on the fixed costs of exporting, all variation in exports across trading partners should occur on the extensive margin. This paper subjects this theoretical prediction to a reality check drawing upon the World Bank's Exporter Dynamics Database (EDD) which has firm-level exports from 50 developing countries to all destinations. Around 50 percent of the variation in exports across trading partners is shown to be along the intensive margin, contradicting the benchmark Melitz-Pareto model. The paper finds that moving from a Pareto to a lognormal distribution of firm productivity allows the Melitz model to successfully match the role of the intensive margin evident in the EDD. The paper then studies the implications of our findings for quantitative trade theory. Using likelihood methods and the EDD, a generalized Melitz model with a joint lognormal distribution for firm productivity, fixed costs and demand shifters is estimated, and exact hat algebra is used to quantify the counterfactual effects of a decline in trade costs on trade flows and welfare in the estimated model. Finally, these effects are compared to those that would be predicted by the Melitz-Pareto model, with the Pareto shape parameter chosen to match the average trade elasticity implied by the estimated Melitz-lognormal model. The paper shows that the effects on welfare turn out to be quite close to those in the standard Melitz-Pareto model even though the effects on trade flows remain different.
The Multifunctional Roles of TGF-β in Navigating the Metastatic Cascade

The role of TGF-β during tumorigenesis is best characterized by the diverse functions this multifunctional cytokine exhibits in early-stage versus late-stage cancers. For instance, during the initial stages of tumorigenesis, TGF-β uniformly acts as a potent tumor suppressor, even in low-grade carcinomas capable of evading the cytostatic activities of TGF-β. However, as carcinoma cells continue to evolve and progress towards more aggressive disease states they typically acquire the ability to surmount the last vestiges of the tumor suppressing activities of TGF-β, ultimately gaining a selective advantage that enables TGF-β to promote their metastatic progression and production of recurrent secondary tumor lesions that are refractory to standard chemotherapies. The molecular, cellular, and microenvironmental mechanisms that permit metastatic carcinoma cells to usurp and commandeer TGF-β for oncogenic activities are highly diverse and remain incompletely understood. Here we review recent advances that provide new insights into how aggressive carcinoma cell populations are selected to respond to the oncogenic activities of TGF-β, focusing specifically on its essential functions coupled to metastatic outgrowth and the acquisition of chemoresistance.
World literacy: obstacles and opportunities.

Literacy is commonly defined as a person's ability to read and write, and illiteracy the inability to read and write, but a true understanding of literacy, and illiteracy, is much more complex than such a simple dichotomy implies. For instance, if one is able to write one's own name, but unable to fill out a job application because he or she does not understand the words 'previous' or 'experience', is that person considered literate or illiterate? How much reading and writing ability must one possess before one can be considered literate? Questions such as this gave birth to the term functional literacy. Functional Literacy refers to one's ability to use language skills to cope with every day demands (IL Y, 1990). In other words, if one's ability to read and write is so limited that it prevents him or her from functioning in society, e.g. purchasing goods, reading a bus schedule or following instructions on a medicine bottle, then that person is by definition, functionally illiterate. It becomes
Reliability of Subjective Probability Forecasts of Precipitation and Temperature

SUMMARY This paper briefly describes some results of operational and experimental programmes in the United States involving subjective probability forecasts of precipitation occurrence and of maximum and minimum temperatures. These results indicate that weather forecasters can formulate such forecasts in a reliable manner.
Physiologic significance and regulation of hepatocellular heterogeneity

Since the concept of hepatocellular heterogeneity was proposed a large body of evidence has accumulated that supports the notion that hepatocytes differ according to their location in the hepatic acinus. Several reviews (l-4) have summarized the numerous studies that have provided evidence that there is morphologic, biochemical, and functional (transport and metabolic) heterogeneity of hepatocytes. What is lacking, however, is a broad understanding of the physiologic meaning of this heterogeneity and the mechanisms by which it is established and maintained. Therefore, the objective of this review is twofold. First, several areas of liver function in which zonal differences in hepatocytes have been established will be analyzed to determine how the observed heterogeneity of hepatocytes may be important for the normal physiologic function of the liver. The areas to be discussed include the metabolism of glucose and ammonia, uptake of substances from sinusoidal blood, and bile secretion. Second, the mechanisms that may be responsible for the regulation of hepatocyte heterogeneity will be discussed. This analysis will draw mainly on data derived from experiments investigating the molecular mechanisms of the heterogeneous expression of the cytochrome Ph5” enzymes within the hepatic acinus. We have attempted to provide not an exhaustive review of the abundant descriptive data on hepatocellular heterogeneity, but rather a biological framework for understanding the functional significance of liver cell heterogeneity, while acknowledging that aspects of this proposal are speculative.
Understanding the Psychology of Diversity

An Introduction to the Psychology of Diversity Categorization and Stereotyping: Cognitive Processes that Shape Perceived Diversity Stereotypes Expressed: Social Processes that Shape Actual Diversity Prejudice: Evaluating Social Differences Understanding Race, Racial Stereotypes, and Racism Understanding Gender Stereotypes and Sexism Understanding Obesity Stereotypes and Weightism Understanding Moral Prejudice: Classism, Homosexism, and Religion Age Stereotypes and Ageism Social Stigma: The Experience of Prejudice Coping with Social Stigma Responding to Social Inequality: Behavioral and Cognitive Interventions for Reducing Prejudice
Dark chiral symmetry breaking and the origin of the electroweak scale

Abstract We study a classically scale-invariant model in which strong dynamics in a dark sector sets the scale of electroweak symmetry breaking. Our model is distinct from others of this type that have appeared in the recent literature. We show that the Higgs sector of the model is phenomenologically viable and that the spectrum of dark sector states includes a partially composite dark matter candidate.
Technology and integration of poly-crystalline diamond piezoresistive position sensor for cochlear implant probe

The possible use of polycrystalline diamond (poly-C) as a piezoresistive position sensor in a cochlear prosthesis is being investigated for the first time. The fabrication process of the poly-C thin film was optimized for compatibility and integration with the Si-based bulk micromachining technology of the cochlear probe. In-situ doped poly-C, films, with a thickness of 1 /spl mu/m, were grown on insulating substrates using MPCVD and patterned by ECR-assisted plasma etching. The piezoresistors can be used as position sensors to detect the curvature and position of the probe during implant surgery. The film quality, electrical properties, contact resistance and piezoresistivity of the poly-C sensors were characterized, which demonstrated a successful integration of diamond technology with the microsystem technology. A gauge factor of 28 was achieved for the poly-C sensors on the probe.
Individualized Vancomycin Dosing in Obese Patients: A Two‐Sample Measurement Approach Improves Target Attainment

tudy Objective To compare the likelihood of vancomycin target trough concentration attainment based on infectious diagnosis and/or minimum inhibitory concentration for the organism by using a two-sample approach versus the prior institutional standard of a trough-only approach in obese patients receiving vancomycin. Design Preintervention and postintervention study. Setting Community acute care hospital. Patients One hundred fifty hospitalized adults with a body mass index (BMI) of 30 kg/m2 or greater and treated with vancomycin for at least 48 hours between July 2013 and March 2014 were evaluated to compare the frequency of steady-state therapeutic trough concentration attainment between two approaches: a trough-only dosing method (preintervention group [75 patients]) and a dosing strategy measuring two vancomycin serum concentrations during the elimination phase (peak and trough) to calculate pharmacokinetic parameters and individualize the maintenance regimen (postintervention group [75 patients]). Data for the preintervention group were retrospectively retrieved from a 4-month period for patients admitted between July and October 2013, prior to implementation of the two-point vancomycin dosing protocol. Initial vancomycin empiric dose selection for both groups utilized the same population-based pharmacokinetic equations. Measurements and Main Results Median (5th–95th percentile) age, weight, and BMI were 59 (34–80) years, 105 (79.8–164) kg, and 34.5 (30.0–55.1) kg/m2, respectively, for all patients. The percentages of initial therapeutic trough concentrations achieved in the preintervention and postintervention groups were 32.0% and 42.7%, respectively (p=0.117). For patients with a second trough measurement, 31.0% in the preintervention group and 65.2% in the postintervention group were within the therapeutic range (p=0.024). Conclusion Measurement of two serum vancomycin concentrations significantly improves subsequent target trough concentration attainment in the obese population.
An Application of Borrayo's Cultural Health Belief Model to HIV/AIDS Seropositive Hispanics Living Along the US/Mexico Border

ABSTRACT This qualitative study examines the factors that led Hispanic men and women residing along the US/Mexico border to be tested for HIV. These factors were identified by applying Borrayo's (1999) Cultural Health Belief Model (CHBM) for Hispanics using grounded theory methodology. Participants consisted of 32 individuals receiving services from five HIV/AIDS demonstration sites in four states along the US/Mexico border. Results indicate partial support for Borrayo's Cultural Health Belief Model. Results also indicate that Hispanic male participants tended to be directly involved in risky behaviors while the female participants were generally monogamous and unaware of their vulnerability to exposure through the risk behaviors of their male partners.
A Ribosomal Coup: E. coli at Last!

In his Perspective, [Moore][1] discusses the atomic-resolution structure that has been obtained by [ Schuwirth et al. ][2] for the Escherichia coli ribosome, the enzyme responsible for protein synthesis in that organism. The vast body of biochemical and genetic data obtained for this particle over the past half century can now be interpreted structurally. [1]: http://www.sciencemag.org/cgi/content/full/310/5749/793 [2]: http://www.sciencemag.org/cgi/content/short/310/5749/827
Steroid hydroxylations in rat adrenal mitochondria. I. Some properties of the C-18 and 11-beta hydroxylations in tightly coupled mitochondria.

Abstract Mitochondrial preparations have been isolated from cortex fragments, adrenal capsules, and intact rat adrenal glands and shown to have high ADP O and respiratory control ratios with all substrates tested. It was necessary to exclude Mg2+ because of an apparently nonmitochondrial Mg2+-stimulated ATPase. These preparations also gave high rates of both the C-18 and 11-β steroid hydroxylation. Steroid hydroxylation with β-hydroxybutyrate or α-ketoglutarate plus malonate was energy-dependent. With the latter substrate, conditions were found which made steroid hydroxylation dependent on both the enzymes of oxidative phosphorylation and on energy conserved at the substrate-linked phosphorylation site. Isocitrate supported steroid hydroxylation by a nonenergy-dependent pathway, presumably via the active NADP-linked isocitric dehydrogenase present in these preparations. Steroid hydroxylation supported by malate was decreased by KCN and uncouplers of oxidative phosphorylation. With malate plus either inorganic phosphate or arsenate as substrate, however, an additional KCN and uncoupler insensitive pathway for corticosterone production became evident. In this latter situation, pyruvate accumulated suggesting the activation of a malic enzyme-like activity by phosphate or arsenate in the intact adrenal mitochondria. It is concluded that rat adrenal mitochondria have efficient energy-conserving reactions, and that steroid hydroxylation may proceed by energy-dependent, nonenergy-dependent, or by both pathways simultaneously depending on the substrate utilized.
Replay-based approaches to revision processing in stream query engines

Data stream processing systems have become ubiquitous in academic and commercial sectors, with application areas that include financial services, network traffic analysis, battlefield monitoring and traffic control. The append-only model of streams implies that input data is immutable and therefore always correct. But in practice, streaming data sources often contend with noise (e.g., embedded sensors) or data entry errors (e.g., financial data feeds) resulting in erroneous inputs and by implication, erroneous query results. Many data stream sources (e.g., Reuters ticker feeds) issue "revision tuples" (revisions) that amend previously issued tuples (e.g. erroneous share prices). A stream processing engine might reasonably respond to revision inputs by generating revision outputs that correct previously emitted query results. We know of no stream processing system that presently has this capability.In this paper, we describe how a stream processing engine can be extended to support revision processing via replay. Replay-based revision processing techniques assume that a stream engine maintains an archive of recent data seen on each of its input streams. These archives are then queried in response to a revision, with the resulting tuples replayed through the system so as to generate corrected query outputs. We first present the design and implementation of the revision processing engine for the Borealis stream processing engine [1]. We then compare techniques for archiving streams to support replay, and then compare the performance and overhead of two revision processing techniques that replay input tuples to recompute and thereby revise previously output query results. These experiments reveal scalability issues due to the overhead required to maintain stream archives, and has motivated our current research on using sampling and data summarization (e.g., histograms) to reduce the data that must be stored in a stream archive.
Tibiocalcaneal arthrodesis using pediatric blade plate

Abstract With improving medical management of diabetes mellitus comes longer survival, so neuropathic arthropathybecomes more frequent, especially that involving the foot and ankle. Although modern plastics and fabrication techniques provide improved orthotic and brace management of this problem, many of the hindfoot/ankle neuropathic deformities become nonbraceable. Surgery becomes necessary to correct alignment so that these deformities are made braceable. Without surgery, skin problems and progression of deformities in a brace produce severe wounds and infections eventually leading to amputations. At our institution, successful management of neuropathic ankle deformities with fragmentation and dissolution of the body of the talus has been successfully performed on 19 patients. Each patient was managed with a pediatric AO condylar blade plate, large AO cannulated screws, and a special cancellous-antibiotic allograft mixture. This procedure is a salvage alternative to below-knee amputation with the activity goal of limited community ambulation. Physiology, pathomechanics, and surgical solutions are covered. A late complication of tibiocalcaneal arthrodesis is a stress fracture at the proximal end of the plate. This is prevented by a bivalved ankle-foot orthosis and a modified shoe.
Use of multidimensional scaling in the selection of wastewater toxicity test battery components

Abstract In aquatic toxicity testing, no single test species is sensitive to all toxicants. Therefore, test batteries consisting of several individual assays are becoming more common. The organisms in a test battery should be representative of the entire system of interest. The results of the assays should be complementary to other components in the test battery to avoid redundancy. With the aid of multidimensional scaling (MDS), a multivariate statistical method, we examined the toxicity data of five bioassays (the continuous Shk1, Polytox®, activated sludge respiration inhibition, Nitrosomonas, and Tetrahymena assays) that could serve as test battery components for the assessment of wastewater toxicity to activated sludge. MDS mapped the five assays into a two-dimensional space and showed that the Nitrosomonas assay should be included in test batteries plus one of the remaining four assays for assessing wastewater toxicity to activated sludge.
Characterization of Nanoparticles and Colloids in Aquatic Systems 1. Small Angle Neutron Scattering Investigations of Suwannee River Fulvic Acid Aggregates in Aqueous Solutions

Fulvic acids (FA) and humic acids (HA) constitute 30–50% of dissolved organic matter in natural aquatic systems. In aqueous solutions, a commonly accepted view is that FA and HA exist as soluble macroligands at low concentration and as supramolecular aggregates at higher concentration. The size, shape and structure of these aggregates are still the subject of ongoing debate in the environmental chemistry literature. In this article, we use small angle neutron scattering (SANS) to assess the effects of solute concentration, solution pH and background electrolyte (NaCl) concentration on the structures of Suwannee River FA (SRFA) aggregates in D2O. The qualitative features of the SANS curves and data analysis are not consistent with the view point that SRFA forms micelle-like aggregates as its concentration in aqueous solution increases. We find that SRFA forms fractal aggregates in D20 with size greater than 242 nm. The SRFA aggregates undergo a significant degree of restructuring in compactness as solution pH, solute concentration and NaCl concentration increase.
Microfabricated reaction and separation systems.

Abstract Over the past year there have been a number of recent advances in the fields of miniaturized reaction and separation systems, including the construction of fully integrated ‘lab-on-a-chip’ systems. Microreactors, which initially targeted DNA-based reactions such as the polymerase chain reaction, are now used in several other chemical and biochemical assays. Miniaturized separation columns are currently employed for analyzing a wide variety of samples including DNA, RNA, proteins and cells. Although significant advances have been made at the component level, the realization of an integrated analysis system still remains at the early stages of development.
The interaction between two wearing surfaces I: Copper sliding on Cu-Be and Cu-Be sliding on Cu-Be

Abstract The work reported in this paper is an investigation of the interaction of the two components of a wear system with reference to the physical properties of both components. Copper sliding on Cu-Be and Cu-Be sliding on Cu-Be were studied using a ball-on-disc machine, Auger spectroscopy and microhardness measurements. The two systems are found to be qualitatively similar classic examples of severe wear. The wear of a Cu-Be disc sliding under a copper ball is, however, greater than the wear of a Cu-Be disc sliding under a Cu-Be ball. This is attributed to work hardening of the copper ball resulting from an interaction between the two wearing surfaces. Microhardness measurements show that the surface of a Cu-Be ball and a Cu-Be disc are not work hardened during a wear experiment. The surface of a copper ball is work hardened, however, and becomes significantly harder than the wear scar on a Cu-Be ball. As a result the Cu-Be disc wears at a faster rate when sliding under a copper ball than it does when sliding under a Cu-Be ball.
Plastic instability in rate-dependent materials

Abstract T he Paper presents a theoretical analysis of the time variation of strain gradients in a tensile specimen of rate-dependent material, the analysis being based on the assumption that the strain rate in the material is a function of the local values of stress and strain. The theory is used to determine the criterion for the growth of strain gradients, and it is shown that for a given material there exists a region of the stress-strain plane defining conditions under which these gradients increase indefinitely with time. The theory is applied to materials with specific types of rate-dependence, and the results are related to experimental data obtained at constant rates of strain.
Rapidly successive, symptomatic, bilateral, spontaneous vertebral artery dissections: treatment with stent reconstruction.

Abstract Background Vertebral artery dissection has been increasingly identified as a cause of ischemic stroke in young adults. This condition is typically secondary to trauma, with spontaneous VA dissection accounting for only a minority of cases. We report the case of a patient with bilateral symptomatic spontaneous VA dissections, presenting in rapid succession. Each ictal event was successfully managed with stent reconstruction and antiplatelet therapy. Case Description A 40-year-old gentleman, with no preceding trauma or apparent inciting event, presented with the acute onset of imbalance, dysarthria, right-sided paresthesias, headache, dysphagia, and dysmetria. Workup revealed a right VA dissection with pseudoaneurysm formation, which was treated with multiple stents. He was scheduled for a 3-week follow-up angiogram and maintained on aspirin and clopidogrel. Three days before his appointment, the patient presented with severe headache and significant worsening of his dysarthria and right-sided dysmetria. Imaging demonstrated a healing right VA pseudoaneurysm, but his left VA was newly dissected with an associated pseudoaneurysm. This lesion was also successfully treated in a similar fashion. The patient did well postoperatively. Follow-up angiography demonstrated excellent vessel patency and pseudoaneurysm stabilization/regression. Conclusion A case of rapidly successive, symptomatic bilateral VA dissections is presented. Ictal events occurred at separate time points and were successfully managed with stent-reconstruction and antiplatelet therapy. Through reporting our experience, we hope to raise awareness regarding this rare condition in young adults.
Ion exchange at a metal–ceramic interface

Abstract We present the results for an interfacial reaction between magnesium aluminate spinel and aluminum metal at 640 °C which, for the first time, show the occurence of ion exchange at a metal–ceramic interface. The exchange reaction occurs by the diffusion of magnesium and aluminum ions across the interface in opposite directions. The enrichment of the spinel in aluminum cations, and the metal in magnesium is confirmed by the appearance of phases of aluminum oxide and magnesium–aluminum intermetallics in the X-ray diffraction spectra. Electron spectroscopic images of spatial elemental distribution provide further evidence for the reaction. A drop in the thermal and electronic conductivities are explained by enhanced scattering of the electrons by solid solution Mg in the aluminum metal. The experiments were carried out on composites consisting of an aluminum matrix with a fine dispersion of spinel particles, whose size was varied while the volume fraction was held constant. Measurable ion exchange reaction was seen only in the composites containing the smaller (one micrometer size) particles. The influence of surface to volume ratio of the particles on the reaction rate confirms that the reaction was interface controlled. The possibility of a nucleation and growth process for the conversion of spinel into alumina and solid solution magnesium was ruled out by quantitative thermodynamic analysis.
Moment invariants in the space and frequency domains

Moment invariants of the Fourier transform of an image are introduced. It is found that a feature set composed of moment invariants from both the space domain and the Fourier domain gives better performance for a wide range of classification tasks than does the same number of moment invariants from either domain alone. Redundancy among moments of the two domains is examined by using the correlation coefficient between the feature kernels as a measure. Examples are used to compare the feature sets and to assess their performance in classification tasks. Moment invariants of the magnitude of the Fourier transform and, by inference, some popular features, such as the spectral ring–wedge detector, are found to fall far short in performance compared with those in which the phase of the Fourier transform is also utilized. Coherent optical systems to compute the dual-domain moment invariants are proposed.
Sub-eV ion deposition utilizing soft-landing ion mobility for controlled ion, ion cluster, and charged nanoparticle deposition

Abstract Sub-eV ion deposition via soft-landing ion mobility has been utilized for a variety of applications. It has allowed for the deposition of a dielectric material onto graphene without introducing defects into the lattice structure. This deposition technique has also been used for surface enhanced Raman studies. Deposited silver has also been used as an alternative MALDI matrix for low mass compounds and shows promise for imaging applications.
Experimental results from an Imarad 8×8 pixellated CZT detector

Abstract This paper reports experimental results obtained from an 8×8 pixellated CZT detector provided by Imarad Imaging Systems. Three arbitrarily selected pixels were independently tested using γ rays of different energies. The signals from an anode pixel and the cathode were read out simultaneously. From the observations of the pulse waveforms from both the anode pixel and the cathode, the electron-injection effect leading to electron–hole combination was not observed. The best energy resolution at 122 keV from the three pixels was 7.8, 6.6 and 9.4 keV, respectively, while resolution at 662 keV was 29.3, 11.8 and 26.5 keV, respectively. The electronic noise from the three pixels was similar (5 keV), so the variation in the best energy resolution indicates material nonuniformity in the detector. For the material underneath the three selected pixels, the mobility-lifetime product for electrons was measured to be 3.4, 2.4 and 1.8 ( ×10 −3 cm 2 / V ), respectively, and the resistivity was measured to be 8, 10 and 8.3 ( ×10 9 Ω cm ), respectively. The variation in these results also shows the material nonuniformity across the detector. In the test with 662 keV γ rays, the pulse-height ratio of the signals from the cathode and pixel can be used to infer the interaction depth of single-pixel events. Results and analyses are presented in this paper.
Immune suppression in polymicrobial sepsis: differential regulation of Th1 and Th2 responses by p38 MAPK.

Abstract Background. Studies have indicated that a shift from a Th1 to a Th2 response occurs that contributes to the late immunosuppression seen during sepsis. However, the mechanism by which this occurs is unknown. In this regard, mediators released in response to sepsis are thought to upregulate a family of stress-induced mitogen-activated protein kinases (MAPKs), such as JNK, ERK, and p38 MAPK, which may play a role in this process. Materials and methods. To determine the role of MAPK in immune suppression, we induced polymicrobial sepsis in C3H/HeN male mice using cecal ligation and puncture (CLP). Splenic lymphocytes were harvested 24 h post-CLP and stimulated with the T-cell mitogen concanavalinA, and the expression and activation of these MAPKs were assessed by Western analysis. To determine the extent to which these MAPKs may have an impact on splenic immune function, cells were pretreated with a 10 μM concentration of the p38 MAPK inhibitor SB203580 or the MEK inhibitor PD98059 or with DMSO vehicle. The cells were then stimulated with 2.5 μg/ml of the T-cell mitogen concanavalin A, and cytokine release was then determined (by ELISA). Results. In the lymphocytes from CLP mice no JNK signal was detected, however, p38 expression and activation were markedly ( P n = 6) increased. In contrast, the expression of activated ERK markedly decreased following septic challenge. The results indicate that p38 MAPK inhibition with SB203580 suppressed the sepsis-induced augmentation of interleukin-10 release while restoring the suppressed Th1 cytokine interleukin-2 release typically encountered following sepsis. Inhibition of ERK had no effect on cytokine release. Neither PD98059 nor SB203580 had an effect on interferon γ release or on proliferative capacity. Conclusion. This would indicate that the induction of p38 MAPK activation in splenocytes contributes to the immunosuppression seen in late sepsis.
Mass transfer from a sphere in an oscillating flow with zero mean velocity

A pseudospectral numerical method is used for the solution of the Navier-Stokes and mass transport equations for a sphere in a sinusoidally oscillating flow with zero mean velocity. The flow is assumed laminar and axisymmetric about the sphere's polar axis. Oscillating flow results were obtained for Reynolds numbers (based on the free-stream oscillatory flow amplitude) between 1 and 150, and Strouhal numbers between 1 and 1000. Sherwood numbers were computed and their dependency on the flow frequency and amplitude discussed. An assessment of the validity of the quasi-steady assumption for mass transfer is based on these results.
Performance influence on the development of tolerance to amphetamine.

This experiment was performed to determine whether performance of a behavior in the drug state was necessary for behavioral tolerance to the effects of that drug to occur. Eight rats trained on a DRL 17.5-sec schedule received daily injections of 1.5 mg/kg d-amphetamine sulfate; four received amphetamine 30 min presession, and four received amphetamine 30 min postsession. Amphetamine given presession initially resulted in a disruption of timing behavior, an increase in response rate, an increase in short IRTs and a decrease in the number of reinforcements received. With continued administration of presession amphetamine the rats developed a partial tolerance to these disruptive effects. Postsession amphetamine had no effect on performance. When tolerance developed in rats receiving presession amphetamine, they were switched to postsession amphetamine; rats receiving postsession amphetamine were switched to presession amphetamine. Amphetamine produced the same disruption of performance in the rats switched to presession amphetamine as was observed in the initial pressession amphetamine group, indicating that tolerance did not develop to amphetamine given postsession. In addition changes in the pattern of responding were observed when amphetamine was initially administered presession.
Re-evaluation of the effects of growth regulators on callus induction and shoot regeneration in Agrobacterium-mediated transformation of lettuce

Lettuce (Lactuca sativa) transformation varies by genotype. Various culture parameters have been studied in order to improve the transformation efficiency of lettuce cultivars. However, no improved transformation procedure for recalcitrant lettuce cultivars has yet been established. Here, we demonstrate the effects of varying concentrations and distinct combinations of growth regulators on recalcitrant lettuce transformation efficiency. More precisely, we assessed differences in the effects of several growth regulator combinations, including N-6(2-isopentenyl)-adenine (2ip), on induction of callus and regeneration of shoots after co-cultivation with Agrobacterium. When two commercial recalcitrant cultivars, Red Romaine and Bibb, were cultured on a medium with 2ip 1 mg l−1, IAA 0.1 mg l−1, and subsequently transferred to a second medium with BA 0.4 mg l−1, NAA 0.05 mg l−1 for selection and shoot regeneration, transformation efficiencies reached 8 and 9%, respectively. Stable integration and transmission of the transgene in T1 generation plants were confirmed by molecular analysis. This procedure represents a simple, efficient, and general means of transforming various lettuce cultivars, including recalcitrant commercial cultivars.
Effect of secondary structure on the thermodynamics and kinetics of PNA hybridization to DNA hairpins.

The binding of a series of PNA and DNA probes to a group of unusually stable DNA hairpins of the tetraloop motif has been observed using absorbance hypochromicity (ABS), circular dichroism (CD), and a colorimetric assay for PNA/DNA duplex detection. These results indicate that both stable PNA−DNA and DNA−DNA duplexes can be formed with these target hairpins, even when the melting temperatures for the resulting duplexes are up to 50 °C lower than that of the hairpin target. Both hairpin/single-stranded and hairpin/hairpin interactions are considered in the scope of these studies. Secondary structures in both target and probe molecules are shown to depress the melting temperatures and free energies of the probe−target duplexes. Kinetic analysis of hybridization yields reaction rates that are up to 160-fold slower than hybridization between two unstructured strands. The thermodynamic and kinetic obstacles to hybridization imposed by both target and probe secondary structure are significant concerns for the c...
Comparison of trajectory models in calculations of N2-broadened half-widths and N2-induced line shifts for the rotational band of H216O and comparison with measurements

In this work, Complex Robert-Bonamy calculations of half-widths and line shifts were done for N2-broadening of water for 1639 transitions in the rotational band using two models for the trajectories. The first is a model correct to second order in time, the Robert-Bonamy parabolic approximation. The second is the solution of Hamilton's equations. Both models use the isotropic part of the atom-atom potential to determine the trajectories. The present calculations used an intermolecular potential expanded to 20th order to assure the convergence of the half-widths and line shifts. The aim of the study is to assess if the difference in the half-widths and line shifts determined from the two trajectory models is greater than the accuracy requirements of the spectroscopic and remote sensing communities. The results of the calculations are compared with measurements of the half-widths and line shifts. It is shown that the effects of the trajectory model greatly exceed the needs of current remote sensing measurements and that line shape parameters calculated using trajectories determined by solving Hamilton's equations agree better with measurement.
A Possible Mechanism for the Diurnal Oscillations of Tropical Cyclones

Abstract A possible mechanism for the diurnal oscillations of tropical cyclones is presented. In the conceptual model developed to explain these features, the diurnal cycle of net radiation at the cloud tops is identified as the primary cause of the oscillations. Radiative cooling of the cloud tops at night steepens the lapse rate and increases convection. This generates a slight intensification in the storm. The reverse occurs during the daytime as the cloud tops absorb solar radiation. This process may be augmented by differential cooling of cloudy and clear areas. This conceptual model is tested through the use of a numerical model. The basic model reproduces well the development of a strong hurricane from a weak tropical depression. The model storm exhibits strong, cyclonic low-level inflow and weaker anticyclonic upper-level outflow. In addition, spiral rainbands and an eye are observed during the simulation. When the fluxes of longwave and shortwave radiation are added into the model, a definite diu...
Arginine kinase isoforms in the closest protozoan relative of metazoans

The genome of the choanoflagellate Monosiga brevicollis contains at least three genes for the phosphoryl transfer enzyme, arginine kinase (AK; EC 2.7.3.3). Bioinformatic analyses of the deduced amino acid sequences of the proteins coded for by two of these genes showed that one of these AKs is cytoplasmic (denoted AK1) while the other appears to have an N-terminal mitochondrial targeting peptide (denoted AK2). Cloning and expression of the cDNA for AK1 yielded considerable soluble AK activity. Three AK2 constructs were expressed – one corresponding to the full length protein and two corresponding to truncated versions in which the signal peptide had been deleted. Expression of the former construct yielded minimal soluble activity. In contrast, significant AK activity was found in both truncated constructs confirming the importance of removal of the targeting peptide for proper folding and catalytic activity. Both AK1 and AK2 are functional oligomers unlike typical AKs which are monomeric. A phylogenetic analysis showed that these choanoflagellate AKs group more closely with a supercluster consisting of cytoplasmic and mitochondrial CKs and invertebrate AKs that evolved secondarily from a CK-like ancestor. Reaction–diffusion constraints in choanoflagellates are likely mitigated by the presence of AK isoforms which facilitate energy transport in these highly polarized cells.
A naturological approach to marketing exchanges: Implications for the bottom of the pyramid

Abstract Marketing as exchange has been the sine qua non of the field for over thirty years. While buyer–seller dyads dominate traditional conversations, other forms of transactions are included as long as value transfer occurs. The most logical extension is Stakeholder Theory, an approach with the same basic structure for understanding, maintaining, and advancing important relationships among firms and their constituencies. Together, they posit that self-contained individuals or units have a marked impact on one another, which passes across defined boundaries at discrete periods of time. Yet the failure to capture organic and dynamic ways in which such entities interact necessities a new approach, such as the naturological perspective that recognizes porous boundaries and reverberating consequences of marketing exchanges, especially among consumers and other impacted parties who survive at or near the proverbial bottom of the economic pyramid.
Interband optical transitions in sodium

Abstract The interband optical conductivity of sodium is calculated including some electron-hole scattering processes. Transitions accompanied by virtual excitation of plasmons enhance the oscillator strength by about 50%.