cssi/SciSciGPT-SciSciNet huggingface dataset:
The Hemoglobins of the Fetus

Summary Almost all vertebrates studied so far, from the most primitive to man, undergo one or more changes in the pattern of their hemoglobins during the course of development. During human ontogeny, for example, three successive types of hemoglobin appear: the embryonic, the fetal, and the adult. Normally, each type gradually disappears followed by the next. Under abnormal stress conditions of the hemopoietic system, however, the genes of fetal hemoglobin can be reactivated in the adult. One important question concerning the ontogeny of the erythroid cell and its control is whether more than one type of hemoglobin coexist within the same erythrocyte. Human fetal and adult hemoglobins, which share a common polypeptide chain, are found within the same erythrocytes. It is not clear, however, whether this is a general phenomenon. To help answer some of the problems of the ontogeny of the hemoglobins, we use as a model the transition from tadpole to frog hemoglobin which is part of the metamorphosis of Rana catesbeiana. Based on morphological criteria, we determined that the site of maturation of the erythroid cells in both premetamorphic and metamorphosing tadpoles is the liver. In agreement with the morphological observations, immunological detection of frog hemoglobin in tadpoles undergoing metamorphosis showed that it appears earliest in the liver. After the completion of metamorphosis the main erythropoietic site is the bone marrow. Rabbit antisera against the major components of the larval and adult hemoglobins were prepared and their properties studied. The antisera were specific for each hemoglobin and showed no detectable cross-reactivity. Fractionated antibodies were conjugated with two different fluorescent dyes and were used for the detection and localization of the larval and adult hemoglobins in individual liver and blood erythroid cells. Both simultaneous and sequential staining with the two fluorescent preparations did not produce any evidence for the simultaneous presence of both larval and adult hemoglobins within the same erythrocyte. Immunochemical determination of the two hemoglobins in individual erythrocytes by a microprecipitation method also suggested that the two hemoglobins do not reside in the same cell. In other experiments, tadpoles were immunized with the major fraction of the adult frog hemoglobin of the same species. They responded by producing antibodies against the adult frog hemoglobin. When some of the immunized tadpoles underwent metamorphosis their hemoglobin was electrophoretically and immunologically different from the hemoglobin of adult frogs, of control froglets, and of tadpoles. These results suggest the possibility of using immunization as a means of interfering specifically with normal development.
Congenital amegakaryocytic thrombocytopenia with congenital deformities and a leukemoid blood picture in the newborn.

Two infants with absent radii are described. Both had hemorrhagic manifestations which occurred within 24 hours of birth, and from which they eventually died. The most important hematologic feature was absence of megakaryocytes in the bone marrow. Five cases showing a similar picture have been recorded, four as amegakaryocytic thrombocytopenia, and one as congenital leukemia. It is suggested that these cases are related on the one hand to Fanconi’s anemia, and on the other to congenital leukemia.
Catalytic Activity and Stability of Two-DimensionalMaterials for the Hydrogen Evolution Reaction

The catalytic performances of the surfaces of two-dimensional (2D) materials are investigated by means of accurate computational thermodynamics approaches, based on first-principles simulations. Re...
Hands-on Curriculum in Optics of Microscopy

ABSTRACT Optics is an important subfield of physics required for instrument design and used in a variety of other disciplines, especially subjects that intersect the life sciences. Students from a ...
aCortex: An Energy-Efficient Multipurpose Mixed-Signal Inference Accelerator

We introduce “aCortex,” an extremely energy-efficient, fast, compact, and versatile neuromorphic processor architecture suitable for the acceleration of a wide range of neural network inference models. The most important feature of our processor is a configurable mixed-signal computing array of vector-by-matrix multiplier (VMM) blocks utilizing embedded nonvolatile memory arrays for storing weight matrices. Analog peripheral circuitry for data conversion and high-voltage programming are shared among a large array of VMM blocks to facilitate compact and energy-efficient analog-domain VMM operation of different types of neural network layers. Other unique features of aCortex include configurable chain of buffers and data buses, simple and efficient instruction set architecture and its corresponding multiagent controller, programmable quantization range, and a customized refresh-free embedded dynamic random access memory. The energy-optimal aCortex with 4-bit analog computing precision was designed in a 55-nm process with embedded NOR flash memory. Its physical performance was evaluated using experimental data from testing individual circuit elements and physical layout of key components for several common benchmarks, namely, Inception-v1 and ResNet-152, two state-of-the-art deep feedforward networks for image classification, and GNTM, Google’s deep recurrent network for language translation. The system-level simulation results for these benchmarks show the energy efficiency of 97, 106, and 336 TOp/J, respectively, combined with up to 15 TOp/s computing throughput and 0.27-MB/mm2 storage efficiency. Such estimated performance results compare favorably with those of previously reported mixed-signal accelerators based on much less mature aggressively scaled resistive switching memories.
Heat shock protein 90 enhances the electron transfer between the FMN and heme cofactors in neuronal nitric oxide synthase.

Heat shock protein 90 (Hsp90) is a key regulator of nitric oxide synthase (NOS) in vivo. Despite its functional importance, little is known about the underlying molecular mechanism. Here, purified dimeric human Hsp90α was used to investigate whether (and if so, how) Hsp90 affects the FMN-heme interdomain electron transfer (IET) step in NOS. Hsp90α increases the IET rate for rat neuronal NOS (nNOS) in a dose-saturable manner, and a single charge-neutralization mutation at conserved Hsp90 K585 abolishes the effect. The kinetic results with added Ficoll 70, a crowder, further indicate that Hsp90 enhances the FMN-heme IET through specific association with nNOS. The Hsp90-nNOS docking models provide hints on the putative role of Hsp90 in constraining the available conformational space for the FMN domain motions.
Cross-Pressured Partisans and Cognitive Dissonance in Low Information Elections: An Experimental Study

The role of cross-pressures on political decisions has been debated since the early voting studies. This literature has recently been revived by showing how priming “wedge” issues in presidential elections can persuade partisans to vote for the opposing party’s candidate. The present research extends theories of cross-pressuring and cognitive dissonance to low information elections by asking the questions: Can partisans be cross-pressured by a competing cue in low-information elections to vote against the party cue? And, how do cross-pressured partisans cognitively justify voting against the party cue? In an experiment conducted in real time during the 2007 Pennsylvania judicial elections, subjects were randomly assigned to either view ads from the candidates, or a control condition. In the ads condition, the Democratic female candidate made a strong appeal to vote for a woman, priming the gender cue as an alternative to the party cue. Using a vote measure verified against the voting record, the findings reveal that by priming this competing cue, partisan voters can be cross-pressured in a low information election, and that self-persuasion regarding a candidate’s partisanship allows cross-pressured partisans to rationalize voting against their party.
Caring for others without losing yourself: An adaptation of the Mindful Self-Compassion Program for Healthcare Communities.

Objective Two studies examined the efficacy of the Self-Compassion for Healthcare Communities (SCHC) program for enhancing wellbeing and reducing burnout among healthcare professionals. Method Study 1 (N = 58) had a quasi-experimental design and compared wellbeing outcomes for the SCHC group compared to a waitlist control group. Study 2 (N = 23) did not include a control group and examined the effect of SCHC on burnout. Results Study 1 found that SCHC significantly increased self-compassion and wellbeing. All gains were maintained for three months. Study 2 found that in addition to enhancing wellbeing, SCHC significantly reduced secondary traumatic stress and burnout. Changes in self-compassion explained gains in other outcomes, and initial levels of self-compassion moderated outcomes so that those initially low in self-compassion benefitted more. Conclusions Findings suggest that the SCHC program may be an effective way to increase self-compassion, enhance wellbeing, and reduce burnout for healthcare professionals.
Impact of carsharing on the mobility of lower-income populations in California

Abstract Mobility is an important quality of life element, with automobile ownership regularly playing an essential role in the mobility of lower-income populations. While carsharing has gained significant momentum in the past decade as an alternative to private vehicle ownership, less is known about the role of carsharing as a mobility mode for lower-income households. To address this gap, this paper examines the impact of carsharing on the mobility of lower-income populations. This study analyzes data from the 2012 California Household Travel Survey by employing a Structural Equation Modeling (SEM), which controls for residential self-selection, car-ownership and carsharing endogeneity issues, and simultaneity bias. Model results indicate that while carsharing membership enhances mobility for both lower- and higher-income households, it has a more substantial effect on mobility among lower-income families, primarily when it is coupled with public transportation services. The findings of this study underscore the importance of the coordination between carsharing operators and public transportation agencies for enhancing the mobility of lower-income populations.
Tuning environmental lighting improves objective and subjective sleep quality in older adults

Abstract This study investigated the effects of two whole-day ambient lighting interventions applied in living rooms on the objective and subjective sleep quality in older adults. Both lighting interventions were designed to apply a direct/indirect ambient illumination that delivered a high illuminance level (500lux) in the morning (8:00–12:00). The illumination was gradually dimmed throughout the day and reached 100lux in the evening (after 20:00). One lighting condition (L1) provided a constant Correlated Color Temperature (CCT) of 2700 K. In the other lighting condition (L2), the CCT changed in a range of 6500 K – 2700 K from the morning to the evening. Twenty-one older adults (mean age = 78.81, 16 female) from three residential communities participated in a counterbalanced crossover study. Participants were exposed to each lighting intervention for nine days. Using 41-day actigraphy and standard questionnaires, objective and subjective data of sleep were collected before, during, and after exposure to interventions. Both interventions significantly increased sleep duration at night compared to the baseline with significantly more increase after L2 intervention. Additionally, the L2 intervention significantly improved sleep efficiency and sleep quality and decreased sleep disturbance, sleep-related impairment, and sleep onset latency compared to Baseline and L1. These results provided promising evidence that daily exposure to a whole-day lighting scheme that follows the light/dark cycle could improve sleep quality in older adults; thereby it could be considered as an effective design solution in creating healthy living environments for the senior population.
Improving image quality in transcranial magnetic resonance guided focused ultrasound using a conductive screen.

Abstract Transcranial Magnetic Resonance guided Focused Ultrasound (TcMRgFUS) has been proven to be an effective treatment for some neurological disorders such as essential and Parkinson's tremor. However, magnetic resonance guidance at 3 Tesla (3T) frequencies and using the large hemispherical transducers required for TcMRgFUS results in artifactual low-signal bands that pass through key regions of the brain. The purpose of this work was to investigate the use of a circular conductive Radio Frequency (RF) screen, that is bent to have a 12 cm radius in one direction and positioned near the top or back of the head, to reduce or remove these artifactual low-signal bands in TcMRgFUS. The impact of using an RF screen to remove these low signal bands was studied in both imaging experiments and electromagnetic simulations. Hydrophone measurements of the acoustic transparency of the bronze 2 mm diameter square mesh screen used in the imaging studies were compared with temperature measurements with and without the screen in heating studies in the TcMRgFUS system. The imaging and simulation studies both show that for the different screen configurations studied in this work, RF screen removes the low-signal bands and increases both homogeneity and signal-to-noise ratio (SNR) throughout the region of the brain. Hydrophone and heating studies indicate that even a 2 mm wire mesh provides minimal attenuation to the ultrasound beam. Simulation results also suggest that a 1 cm mesh will provide adequate artifact suppression with even less ultrasound attenuation. An RF screen that disrupts the natural waveguide nature of the transducer in the 3T MR environment can change the electromagnetic field profile to reduce unwanted artifacts and provide an imaging region which has more homogeneity and higher SNR throughout the brain.
Employees’ voluntary disclosures about business outlook and labor investment efficiency

We examine how employees’ voluntary disclosures about business outlook are related to labor investment efficiency by using data from Glassdoor.com. We hypothesize that due to the popularity and informativeness of employee voluntary disclosure through social media as a form of crowd wisdom in labor markets, more positive business outlook disclosed by employees can significantly reduce firms’ labor adjustment costs by attracting more job applicants in a timely matter, resulting in higher labor investment efficiency. Consistent with the hypothesis, we document that positive employees’ business outlook disclosures enhance labor investment efficiency by reducing both over-investment and under-investment in labor. We mitigate endogeneity concern by employing sub-sample analysis and Anti-SLAPP laws as an exogenous shock.
El malditismo de Fernando Vallejo como espectáculo melodramático

El analisis de Hector Hoyos se aproxima al arte de provocacion de Vallejo como un espectaculo que subvierte la estructura afectiva del melodrama. En el presente articulo, Hoyos propone que tanto en La Virgen de los sicarios como en La puta de babilonia la voz de Vallejo, mas alla de buscar simplemente escandalizar a su publico, aprovecha sobre todo la oportunidad para insertarse en la coyuntura de la reproduccion mediatica, del espectaculo melodramatico montado en torno a los iconos de Pablo Escobar y Juan Pablo II. El malditismo parodico de Vallejo es para Hoyos tardio y espectacular y esta sostenido por el melodrama, un melodrama de fetichismos, reducciones y lugares comunes que -en medio de rancheras, tangos, villanos y brillantes corazones rojos- Vallejo busca trastornar desde adentro.
Factors affecting media agenda-setting: An exploratory study

Factors which might serve as obstacles to the agenda-setting process of the news media are examined. Data were examined from an investigation in which seven of 60 tests involving two media (the New York Times and CBS Evening News) did not produce agenda-setting effects. Post hoc examinations of die conditions under which these non-significant tests occurred suggest five categories for the lack of effects: 1. Message variables: Some issues became less obtrusive and less sensational than at previous periods; 2. Media variables: Patterns of coverage changed, in which media presented sporadic coverage of some issues, and media presented conflicting salience cues; 3. Public variables: The public retained pet issues, such as dissatisfaction with government and moral decline, which received little media coverage, and the public influenced media coverage on some issues, such as energy and drugs; 4. Public officials interfered: The U.S. president and other important news sources influenced news coverage; 5. Cues f...
CHANGE AND RESISTANCE: THE COST/BENEFIT FACTOR

This article looks at organizational activity within libraries with the assumption that the human cost of change must be a factor in planning. If that cost outweighs the human benefits, the change will result in fewer benefits. Therefore, it is better to take the time to attend to staff concerns and needs during the process. The costs of dealing with the effects after the fact will be at least as great and certainly more stressful.
DNase I and Hydroxyl Radical Characterization of Chromatin Complexes

The native chromatin complex within most eukaryotic nuclei is very difficult to study by biochemical means, so researchers have developed methods for studying smaller portions of the complex. This unit details the use of DNase I and hydroxyl radicals to characterize histone-DNA interactions within such portions of the complex. DNase I digestion can be used to determine what regions of a DNA segment are intimately associated with the core histone proteins and what regions are more like naked DNA (i.e., linker DNA within the nucleosomal repeat). The finer deatils of histone-DNA interactions and DNA structure within these complexes is best characterized by digestion with the hydroxyl radical. Both reagents may be used to assess the degree and homogeneity of rotational and translational positioning within isolated chromatin complexes.
Natural Regulatory T Cells and De Novo-Induced Regulatory T Cells Contribute Independently to Tumor-Specific Tolerance

Thymus-derived, naturally occurring CD4 + CD25 + Foxp3 + regulatory T cells (nTregs) and Tregs induced in the periphery (iTregs) have both been implicated in regulating immune responses. However, the relationship between these populations in the same host, and their relative contribution to the overall Treg pool, has not been examined. Using a tumor-induced T cell tolerance model, we find that expansion of nTregs and de novo generation of iTregs both contribute to tumor-specific T cell tolerance. In this system in which the number of tumor-specific nTregs can be controlled, the efficiency of nTreg expansion significantly exceeds that of the induction of Tregs from uncommitted progenitors in the tumor-bearing host. However, pre-existing nTregs are neither required for the induction of Tregs nor measurably impact on the extent of their accumulation. Instead, induction of Ag-specific regulatory cells from naive cells is intrinsically influenced by the tumor microenvironment and the presence of tumor Ag.
Prevalence of Regurgitation and Reingestion in Orangutans Housed in North American Zoos and an Examination of Factors Influencing its Occurrence in a Single Group of Bornean Orangutans

Very little research has explored regurgitation and reingestion (R/R) in orangutans. We first aimed to determine the prevalence of R/R in the North American zoo population through a survey of accredited institutions. We report the prevalence of R/R in orangutans >4 years of age as 35% with some sex and species differences. Additionally, survey respondents reported fruit and sweet foods as the most common triggers of R/R. We also explored rates of R/R in a single group of Bornean orangutans at Cleveland Metroparks Zoo. We examined the relationship between R/R and feeding schedule and opportunistically observed rates of R/R with and without the presence of browse and sweet foods. We found evidence that R/R is associated with feeding time and that the presence of browse significantly increased the amount of time that animals spent feeding. There was a trend toward decreased R/R when browse was available. We also observed higher rates of R/R when sweet foods were available and we propose that this may have mitigated some of the beneficial effects of browse. We suggest that future studies look further at nutritional influences on R/R behavior.
Climate Geoengineering and the Role of Public Deliberation: A Comment on the U.S. National Academy of Sciences' Recommendations on Public Participation

This article seeks to critique the discussion of the role of public deliberation in climate geoengineering governance, with a focus on the approach taken by the US National Academy of Sciences in its major reports on geoengineering, released in February of 2015. The article suggests that the NAS's dedication to public deliberation was insufficient. It also proffers some potential options to strengthen the role of public deliberation in climate geoengineering governance.
Cytokine Regulation of Facilitated Glucose Transport in Human Articular Chondrocytes

Glucose serves as the major energy substrate and the main precursor for the synthesis of glycosaminoglycans in chondrocytes. Facilitated glucose transport represents the first rate-limiting step in glucose metabolism. This study examines molecular regulation of facilitated glucose transport in normal human articular chondrocytes by proinflammatory cytokines. IL-1β and TNF-α, and to a lesser degree IL-6, accelerate facilitated glucose transport as measured by [ 3 H]2-deoxyglucose uptake. IL-1β induces an increased expression of glucose transporter (GLUT) 1 mRNA and protein, and GLUT9 mRNA. GLUT3 and GLUT8 mRNA are constitutively expressed in chondrocytes and are not regulated by IL-1β. GLUT2 and GLUT4 mRNA are not detected in chondrocytes. IL-1β stimulates GLUT1 protein glycosylation and plasma membrane incorporation. IL-1β regulation of glucose transport in chondrocytes depends on protein kinase C and p38 signal transduction pathways, and does not require phosphoinositide 3-kinase, extracellular signal-related kinase, or c-Jun N-terminal kinase activation. IL-1β-accelerated glucose transport in chondrocytes is not mediated by endogenous NO or eicosanoids. These results demonstrate that stimulation of glucose transport represents a component of the chondrocyte response to IL-1β. Two classes of GLUTs are identified in chondrocytes, constitutively expressed GLUT3 and GLUT8, and the inducible GLUT1 and GLUT9.
Disruption of coordinated cardiac hypertrophy and angiogenesis contributes to the transition to heart failure

Although increased external load initially induces cardiac hypertrophy with preserved contractility, sustained overload eventually leads to heart failure through poorly understood mechanisms. Here we describe a conditional transgenic system in mice characterized by the sequential development of adaptive cardiac hypertrophy with preserved contractility in the acute phase and dilated cardiomyopathy in the chronic phase following the induction of an activated Akt1 gene in the heart. Coronary angiogenesis was enhanced during the acute phase of adaptive cardiac growth but reduced as hearts underwent pathological remodeling. Enhanced angiogenesis in the acute phase was associated with mammalian target of rapamycin-dependent induction of myocardial VEGF and angiopoietin-2 expression. Inhibition of angiogenesis by a decoy VEGF receptor in the acute phase led to decreased capillary density, contractile dysfunction, and impaired cardiac growth. Thus, both heart size and cardiac function are angiogenesis dependent, and disruption of coordinated tissue growth and angiogenesis in the heart contributes to the progression from adaptive cardiac hypertrophy to heart failure.
Ion molecule reaction H/D exchange as a probe for isomeric fractionation in chromatographically separated natural organic matter

Abstract Mass spectrometry (MS) is a powerful tool for analyzing complex mixtures such as natural organic matter (NOM), humic substances (HS), and petroleum. MS disperses and resolves analyte ions with far greater peak capacity than any chromatographic technique. Unfortunately, even the highest-resolution MS cannot separate isomers. Therefore, tandem chromatography and MS techniques must be developed that combine isomeric separation with detailed compositional characterization. To develop such techniques, a means of identifying isomeric separation is requisite. Hydrogen/deuterium exchange (HDX) is an attractive means to distinguish isomers because the ability to exchange hydrogen(s) depends critically on structure. Here, both solution H/D exchange and ion-molecule reaction (IMR) H/D exchange were investigated. We present the first IMR results for fully resolved NOM isobars and the first direct evidence of isomeric separation of NOM through reversed-phase chromatography.
Anomalous hydrostatic pressure dependence of the Curie temperature of the Kondo-lattice compound YbNiSn to 38 GPa.

The dependence of the Curie temperature ${\mathit{T}}_{\mathit{o}}$ of ferromagnetic YbNiSn on hydrostatic pressure to 38 GPa has been determined in an ac susceptibility measurement in a diamond-anvil cell loaded with dense helium as a pressure medium. The Curie temperature ${\mathit{T}}_{\mathit{o}}$(0)\ensuremath{\simeq}5.5 K initially increases with applied pressure at the rate +1.7 K/GPa, passing through a maximum value ${\mathit{T}}_{\mathit{o}}^{\mathrm{max}}$\ensuremath{\simeq}7.7 K at \ensuremath{\sim}2 GPa. No transition was detected above 2 K for 9.4 GPaP38 GPa. The present results are discussed within the framework of a phase diagram proposed by Doniach for Kondo-lattice systems. The observed asymmetry in ${\mathit{T}}_{\mathit{o}}$(P) about ${\mathit{P}}_{\mathit{m}}$=P(${\mathit{T}}_{\mathit{o}}^{\mathrm{max}}$), which is opposite to that found in Ce compounds, can be readily understood in Doniach's model if the Kondo temperature of YbNiSn decreases under pressure.
A Brief Biography and Appreciation of Ingram Olkin

Ingram Olkin, known affectionately to his friends in his youth as “Red,” was born July 23, 1924 in Waterbury, Connecticut. He was the only child of Julius and Karola (Bander) Olkin. His family moved from Waterbury to New York City in 1934. Ingram graduated from the Bronx’s DeWitt Clinton High School in 1941, and began studying statistics in the Mathematics Department at the City College of New York. After serving as a meteorologist in the Air Force during World War II (1943–1946), achieving the rank of First Lieutenant, Ingram resumed his studies at City College. He received his B.S. in mathematics in 1947.
In situ ground deformation measurements from the summit of Axial Volcano during the 1998 volcanic episode

Since September 1987, seafloor instrumentation monitoring ground deformation has been maintained on the summit of Axial Volcano on the central Juan de Fuca Ridge. During a January 1998 volcanic episode, pressure records from the central caldera showed a significant increase in pressure, indicating caldera subsidence of over 3 m. This observed subsidence is interpreted to represent volcanic deflation as magma is erupted and/or injected into the volcanic flanks. Temperature anomalies of nearly 0.45°C were also observed. A comparison of the subsidence record with hydroacoustic recordings indicates a continuous volcanic tremor signal coincident with the subsidence event. The time-coincidence of subsidence of the summit caldera with migration of epicenters into the volcanic rift zones confirms that during the 1998 episode, the volcanic flanks were supplied by lateral dike injection from a central magma body, rather than locally derived magma sources.
Some Anaxagorean Thoughts on Atomism, Dualism and the Effect of the Mind on the Monad

The definition of the "atomistic society" proffered by Rubel in his introduction and in Across the Tracks is intriguing in its insistence on coupling characteristics of social structure with those of personality or sentiment. Rather than duplicate Honigman's review of the various ethnographic contributions I shall, in this paper, confine my remarks to the questions posed by Rubel's definition.
Shuffles of permutations and the Kronecker product

The Kronecker product of two homogeneous symmetric polynomialsP 1,P 2 is defined by means of the Frobenius map by the formulaP 1oP 2=F(F ?1 P 1)(F ?1 P 2). WhenP 1 andP 2 are the Schur functionsS I ,S J then the resulting productS I oS J is the Frobenius characteristic of the tensor product of the two representations corresponding to the diagramsI andJ. Taking the scalar product ofS I oS J with a third Schur functionsS K gives the so called Kronecker coefficientc I,J,K = . In recent work lascoux [7] and Gessel [3] have given what appear to be two separate combinatorial interpretations for thec I,J,K in terms of some classes of permutations. In Lascoux's workI andJ are restricted to be hooks and in Gessel's both have to be zigzag partitions. In this paper we give a general result relating shuffles of permutations and Kronecker products. This leads us to a combinatorial interpretation of forS I a product of homogeneous symmetric functions andJ, K unrestricted skew shapes. We also show how Gessel's and Lascoux's results are related and show how they can be derived from a special case of our result.
Endothelin mediates some of the renal actions of acutely administered angiotensin II

Recent studies suggest that endogenous endothelin mediates much of the vasoconstrictor activity and vascular fibrotic damage caused by chronic administration of angiotensin II. The present study uses the mixed endothelin-A and endothelin-B receptor antagonist bosentan and the endothelin-A-selective blocker BQ-123 to study the contribution of endogenous endothelin to the pressor and renal action of acutely administered angiotensin II in conscious, chronically catheterized rats. Exposure to angiotensin II at 0.48 pmol 0.5 ng/100 g body weight per min IV (low dose) and 1.91 pmol 2.0 ng/100 g body weight per min IV (high dose) raised mean arterial blood pressure (18+/-4 mm Hg, P<0.01, and 39+/-4 mm Hg, P<0.005, respectively) while also increasing renal vascular resistance (4.3+/-1 mm Hg/mL per min, P<0.001, and 10+/-1 mm Hg/mL per min, P<0.001, respectively). In the presence of bosentan, pressor and renal vasoconstrictor responses to low-dose angiotensin II were blunted (P<0.02 and P<0.01, respectively), and the results with BQ-123 were similar. In contrast, these parameters were unaffected during high-dose angiotensin II infusion+bosentan, although BQ-123 did selectively reduce the rise in renal vascular resistance, possibly via an endothelin B-mediated nitric oxide effect. In contrast, high-dose angiotensin II caused natriuretic and diuretic effects that were completely prevented by bosentan. These results show that endothelin (via endothelin A) contributes to the pressor and renal vasoconstrictor actions of acutely administered low-dose angiotensin II. Furthermore, our data suggest that the previously described angiotensin II-induced natriuresis and diuresis observed with a high pressor dose of angiotensin II is mediated by endothelin.
Experimental Verification of Resilient Deformation for Granular Subgrades

Results of an experimental program utilizing the repetitive rigid plate load test in a test-pit facility and the laboratory resilient modulus test are presented for five typical subgrades in Florida. The subgrade materials were tested in the test pit under three different moisture conditions, that is, (1) optimum, (2) drained and dried, and (3) soaked. Laboratory resilient modulus tests were conducted on reconstituted soil samples simulating the various moisture conditions. The resilient modulus was significantly affected by the moisture content of granular subgrades. A comparison between the deformations measured from the test-pit test and the deformation calculated from the laboratory test was made. It was experimentally verified that the resilient modulus resulting from the laboratory triaxial test could be used to predict the resilient deformation of pavement subgrade layers.
Identification of Streptomyces coelicolor genes involved in regulation of antibiotic synthesis

To define genetic elements that regulate antibiotic synthesis, we screened for mutations that visibly blocked synthesis of Streptomyces coelicolor's two pigmented antibiotics and found mutant strains in which all four antibiotics were blocked. The responsible mutations defined two loci, absA and absB. Two additional approaches to defining genes have been taken: isolation of cloned genes with a dominant negative effect on antibiotic synthesis and isolation of genes which, in multicopy, can compensate for specific mutational blocks. These genes apparently function in a global regulatory pathway (or network) for control of antibiotic synthesis.
Science Teacher Educators as a Community of Practice

As a community focused on ensuring excellence in science teacher education, most of us would identify ourselves as science teacher educators. This is, in part, because we teach methods courses, oversee field experiences, and provide professional development for science teachers; but, not everyone who contributes to teacher education would call themselves a teacher educator. For instance, most K-12 classroom teachers or college science faculty would not label themselves as teacher educators, even though they are important educators of teachers. In addition, science teacher education has attracted the attention of college deans, school principals, and community leaders as part of a national emphasis on improving science, technology, engineering, and mathematics (STEM) education. These people also are not likely to consider themselves to be science teacher educators. In this editorial letter, I propose a framework for thinking about what defines us as science teacher educators so we can think more clearly about how to encourage active participation from a broader membership and guide the efforts of our potential partners in improving science teacher education.
Parameter estimation for photographic tone reproduction

Tone reproduction algorithms attempt to compress a large range of pixel values into a smaller range that is suitable for display on devices with limited dynamic range. A recently proposed tone reproduction operator achieved this goal by emulating photographic practice. Like in photography, the manual tuning of a small set of intuitive parameters was required. In this paper we extend this photographic tone reproduction algorithm with an automatic method for estimating these parameters. The estimation process is also based on photographic practice. The resulting operator produces good images and does not require manual parameter tuning. Sample source code is available online.
MORPHOLOGY, FINE STRUCTURE, AND ONTOGENY OF THE STINGING EMERGENCE OF URTICA DIOICA

A B S T R A C T Stinging emergences in Urtica dioica L. characteristically possess an elongate stinging cell and a multicellular pedestal. The emergence is derived from the epidermal and subepidermal cell layers. The apical wall of the stinging cell is composed of silica bodies which decrease basipetally in concentration. The basal portion of the cell wall of the stinging cell is devoid of silica bodies and lacks primary pit fields or pits between it and the pedestal cells. X-ray microanalysis of electron dense particles located in the stinging cell ER-golgi complex indicate that these particles contain silicon. There is no ultrastructural evidence for the presence of a toxin synthesizing system or a toxin itself. STINGING EMERGENCES are known to occur in four dicotyledonous plant families, Urticaceae, Euphorbiaceae, Loasaceae, and Hydrophyllaceae. However, the members of the Urticaceae are perhaps the most familiar and cosmopolitan. A stinging emergence is defined on the basis of its morphology, ontogeny, and capacity to inflict pain by the active release of a toxin from the stinging cell. Since their first description and illustration
Chronic substrate limitation of silicic acid uptake rates in the western Sargasso Sea

Abstract The kinetics of Si uptake at the JGOFS Bermuda Atlantic Time-series Study (BATS) Site in the western Sargasso Sea (31°50′N, 64°10′W) were examined on nine cruises between November 1991 and November 1993. Si uptake rates were severely substrate-limited on every cruise during all seasons. Surprisingly, the observed uptake kinetics were among the most inefficient examined to date despite persistently low (
ImmunoPods: Polymer Shells with Native Antibody Cross‐Links

Recently, we described the discovery of a novel gold nano-particle (AuNP) catalyzed reaction, which allows one to make heavily cross-linked polymer shells on the surface of the NP.[1] With this reaction, the NP acts both as a scaffold and catalyst to facilitate the cross-linking of linear polymers with propargyl ether side chains. Specifically, it has been postulated that hydroxy groups, formed from the hydrolysis of the propargyl ethers, add to the alkynes adsorbed on the gold surface, leading to cross-linking of the polymer.[2] Importantly, the NP core can be subsequently removed to form hollow polymer nanopods. These structures, which are highly adaptable through choice of polymer and AuNP template, show promise for many applications, spanning molecular diagnostics,[3] drug delivery,[4] materials synthesis, and colloidal crystal design.[5] However, before they can be fully utilized, methods for functionalizing them with bioactive structures must be developed. In this regard, we have devised methods for making nanopods from oligonucleotides with modified bases to generate polyvalent oligonucleotide nanostructures, which now constitute an entire class of single-entity intracellular gene regulation agents.[6] Herein, we address the challenge of creating nanopods functionalized with antibodies (Abs) by creating a class of materials, termed immunopods (IPs), structures that can be made from Abs and the appropriate linear polymers with propragyl ether side chains in a one-pot fashion, and then explore their ability to selectively target cells. IPs are important entries in the class of structures that can be made by gold-particle surface-templated and catalyzed approaches since they can enable a wide variety of pharmaceutical studies and potential applications.
Using long-term occupancy information to inform the management of Cape Sable seaside sparrows in the Everglades

Abstract Wildlife managers must find ways of detecting meaningful shifts in population size or extent if they are to effectively implement recovery programs for threatened and endangered species. This task is made difficult by the oft-flawed survey information to which they have access. Here we describe such a situation for the Cape Sable seaside sparrow, an Everglades endemic. An unusually long-term survey has been conducted across this subspecies’ entire range, however extracting abundance information from this survey has proven difficult and controversial. Here we treat the information contained in the survey as presence–absence data and evaluate occupancy trends through time. We also evaluate the probability that each survey site has been effectively abandoned by sparrows and the manner in which site utilization varies through time and across space. Our results indicate that Cape Sable seaside sparrows have experienced two episodes of occupancy declines. Two subpopulations continue to decline in occupancy to the present, and only one shows a consistent upswing. In accordance with these trends, we also show that the two populations that have a decreasing trend in occupancy also hold the vast majority of sites that have been abandoned by sparrows. Finally, we show a dynamic pattern of site utilization when sparrow occupancy is low and a coalescence of site usage as occupancy increases. Overall our results confirm previous proclamations of severe decline in the Cape Sable seaside sparrow numbers and argue for continued vigilance in ensuring no further reductions. We also illustrate how presence–absence information can be used to extract quite detailed information on changes in habitat occupancy and site usage that are highly relevant to managers.
Zur Stabilisierung des Phenyl‐Kations

Mit Hilfe der erweiterten Huckel-Methode wird der Effekt der „through bond” -Wechsel-wirkung zur Stabilisierung des Phenyl-Kations B und einiger am Bruckenkopf ionisierter Bicyclen C diskutiert. On the Stabilisation of the Phenyl Cation Calculations of the extended Huckel type are used to discuss the effect of through bond interaction on stabilizing the phenyl cation B and bridgehead ions C.
Some molecular transport characteristics in binary homogeneous systems

The behaviors of several diffusion coefficients are shown for the methane-n-butane system under conditions such that solutions are very nonideal and the concentrations of both components are significant. The coefficient proposed by Chapman and Cowling shows the least variation with state and is recommended for use under such conditions in hydrocarbon systems. Several other coefficients commonly used show large variations with state and coefficients using concentrations as a potential are even negative in certain regions.
The interpersonal effects of Facebook reassurance seeking.

Abstract Background Social networking sites like Facebook represent a potentially valuable means for individuals with low self-esteem or interpersonal difficulties to connect with others; however, recent research indicates that individuals who are most in need of social benefits from Facebook may be ineffective in their communication strategies, and thereby sabotage their potential to benefit interpersonally. The current study tested whether reassurance seeking via Facebook negatively influenced self-esteem, and whether this change in self-esteem mediated the relationship between Facebook reassurance seeking and greater thwarted belongingness and perceived burdensomeness. Method Participants completed measures online at two time-points approximately 24 days apart. Results Results provided evidence that Facebook reassurance seeking predicted lower levels of self-esteem, which in turn predicted increased feelings that one does not belong and that one is a burden. Limitations Key limitations to this study include our use of a predominantly young, female, Caucasian sample, a novel reassurance seeking measure, and only evaluating two time points. Conclusions These results suggest that Facebook usage has the potential for negative and far-reaching influences on one's interpersonal functioning.
Representation And Recognition Of Elongated Regions In Aerial Images

The recent advances in model-based image understanding systems for aerial imagery have used intermediate-level interpretations of the low-level segmentations in terms of generic shape properties. This paper is concerned with those features recognizable in the context of having an elongated shape as evidenced from the planar point sets obtained from spectral classifications. The basic processing technique can be described as linear-strip point clustering, using the minimum spanning tree as a connectivity constraint. The algorithms are applied to classifications of suburban road networks. The major elongated regions are detected for the given strip width, and where connectivity can be established across any gaps in the segmentation.
Timing of elective surgery as a perioperative outcome variable: analysis of pancreaticoduodenectomy

Objectives:The timing of major elective operations is a potentially important but rarely examined outcome variable. This study examined elective pancreaticoduodenectomy (PD) timing as a perioperative outcome variable. Methods:Consecutive patients submitted to PD were identified. Determinants of 90-day morbidity (prospectively graded and tracked), anastomotic leak or fistula, and mortality, including operation start time (time of day), day of week and month, were assessed in univariate and multivariate analyses. Operation start time was analysed as a continuous and a categorical variable. Results:Of the 819 patients identified, 405 (49.5%) experienced one or more complications (total number of events = 684); 90-day mortality was 3.5%. On multivariate analysis, predictors of any morbidityincluded male gender (P = 0.009) and estimated blood loss (P = 0.017). Male gender (P = 0.002), benign diagnosis (P = 0.002), presence of comorbidities (P = 0.002), American Society of Anesthesiologists (ASA) score (P = 0.025), larger tumour size (P = 0.013) and positive resection margin status (P = 0.005) were associated with the occurrence of anastomotic leak or fistula. Cardiac and pulmonary comorbidities were the only variables associated with 90-day mortality. Variables pertaining to procedure scheduling were not associated with perioperative morbidity or mortality. Operation start time was not significant when analysed as a continuous or a categorical variable, or when stratified by surgeon. Conclusions:Perioperative outcome after PD is determined by patient, disease and operative factors and does not appear to be influenced by procedure timing.
Hypomethylation of DNA and the insulin-like growth factor-II gene in dichloroacetic and trichloroacetic acid-promoted mouse liver tumors

Dichloroacetic acid (DCA) and trichloroacetic acid (TCA) are mouse liver carcinogens. DNA hypomethylation is a common molecular event in cancer that is induced by DCA and TCA. Hypomethylation of DNA and the insulin-like growth factor-II (IGF-II) gene was determined in DCA- and TCA-promoted liver tumors. Mouse liver tumors were initiated by N-methyl-N-nitrosourea and promoted by either DCA or TCA. By dot-blot analysis using an antibody for 5-methylcytosine, the DNA in DCA- and TCA-promoted tumors was demonstrated to be hypomethylated. The methylation status of 28 CpG sites in the differentially methylated region-2 (DMR-2) of mouse IGF-II gene was determined. In liver, 79.3 +/- 1.7% of the sites were methylated, while in DCA- and TCA-treated mice, only 46.4 +/- 2.1% and 58.0 +/- 1.7% of them were methylated and 8.7 +/- 2.6% and 10.7 +/- 7.4% were methylated in tumors. The decreased methylation found in liver from mice exposed to DCA or TCA occurred only in the upstream region of DMR-2, while in tumors it occurred throughout the probed region. mRNA expression of the IGF-II gene was increased in DCA- and TCA-promoted liver tumors but not in non-involved liver from DCA- and TCA-exposed mice. The results support the hypothesis that DNA hypomethylation is involved in the mechanism for the tumorigenicity of DCA and TCA.
Autoradiographic localization of 5-hydroxytryptamine1A, 5-hydroxytryptamine1B and 5-hydroxytryptamine1C/2 binding sites in the rat spinal cord

Abstract Autoradiographic techniques revealed that 5-hydroxytryptamine 1A , 5-hydroxytryptamine 1B and 5-hydroxytryptamine 1C/2 binding sites are differentially distributed in the spinal cords of adult male rats. In the dorsal horn, 5-hydroxytryptamine 1A sites were dense in all laminae; 5-hydroxytryptamine 1B sites were more dense in laminae I, III and IV than in lamina II; while 5-hydroxytryptamine 1C/2 sites were very sparse. The dorsal commissure gray matter also exhibited very dense 5-hydroxytryptamine 1A and 5-hydroxytryptamine 1B binding. In the intermediate and central gray matter, all three sites were moderately dense at autonomic levels, with exceptionally dense 1C/2 binding restricted to the intermediolateral nucleus at rostral thoracic levels. In the ventral horn, 5-hydroxytryptamine 1A and 5-hydroxytryptamine 1B sites were very sparse (except for very dense 5-hydroxytryptamine 1A sites located in the dorsolateral nucleus of the pudendal nerve), while 5-hydroxytryptamine 1C/2 sites were relatively dense in motor nuclei. Surprisingly, 5-hydroxytryptamine 1B sites were moderately dense in the dorsal column corticospinal tract. These studies will provide an anatomical perspective for interpretation of the complex role of 5-hydroxytryptamine in regulating spinal cord function.