cssi/SciSciGPT-SciSciNet huggingface dataset:
RNA polymerase, manganese and RNA metabolism of zinc sufficient and deficient E. gracilis.

Summary The RNA from zinc sufficient (+Zn) and deficient (−Zn) E. gracilis have been isolated and the three major RNA classes separated by affinity chromatography on oligo-(dT) and DBAE celluloses. The total RNA content and the ribosomal and transfer RNA fractions are the same in (+Zn) and (−Zn) cells. In (−Zn) cells, the messenger RNA fraction doubles and its base composition is altered, resulting in a two-fold increase in the G+C/A+U ratio. We have examined the role of Mn in determining these changes in RNA, since the intracellular content of this metal increases in (−Zn) cells. Increasing the Mn (II) content from 2 to 10 mM in assays with RNA polymerase from (−Zn) cells increases the incorporation of GMP relative to UMP from 1.0 to 3.5. Further, the ratios of CMP/GMP incorporation are 1.0, 2.2 and 1.2 in assays with 2, 5, 10 mM Mn (II), respectively. Thus, Mn (II) concentration can significantly alter function of RNA polymerase from (−Zn) E. gracilis cells.
The sorption of glycine by a strong cation exchange resin

Abstract The exchange behavior of the amino acid glycine with respect to the sodium form of a strong cation exchange resin was studied. It was found that the distribution of glycine between the internal solvent volume of the resin and the volume of the ambient solution could be described in terms of a model based upon the existence of a Donnan equilibrium and defined in terms of the first dissociation constant of the amino acid, K 1 , and other parameters of the sytem. Experimental results in support of some theoretical considerations based on this model are presented.
Constitutive Activation of the Mitogen Activated Protein Kinase Pathway Impairs Vitamin D Signaling in Human Prostate Epithelial Cells

We studied the effect of prolonged activation of mitogen-activated protein kinase (MAPK) signaling on 1,25 dihydroxyvitamin D (1,25(OH)2D3) action in the immortalized human prostate epithelial cell line RWPE1 and its Ki-Ras transformed clone RWPE2. 1,25(OH)2D3-treatment caused growth arrest and induced gene expression in both cell lines but the response was blunted in RWPE2 cells. Vitamin D receptor (VDR) levels were lower in RWPE2 cells but VDR over-expression did not increase vitamin-D-mediated gene transcription in either cell line. In contrast, MAPK inhibition restored normal vitamin D transcriptional responses in RWPE2 cells and MAPK activation with constitutively active MEK1R4F reduced vitamin-D-regulated transcription in RWPE1 cells. 1,25(OH)2D3-mediated transcription depends upon the VDR and its heterodimeric partner the retinoid X receptor (RXR) so we studied whether changes in the VDR–RXR transcription complex occur in response to MAPK activation. Mutation of putative phosphorylation sites in the activation function 1 (AF-1) domain (S32A, T82A) of RXRα restored 1,25(OH)2D3-mediated transactivation in RWPE2 cells. Mammalian two-hybrid and co-immunoprecipitation assays revealed a vitamin-D-independent interaction between steroid receptor co-activator-1 (SRC-1) and RXRα that was reduced by MAPK activation and was restored in RWPE2 cells by mutating S32 and T82 in the RXRα AF-1 domain. Our data show that a common contributor to cancer development, prolonged activation of MAPK signaling, impairs 1,25(OH)2D3-mediated transcription in prostate epithelial cells. This is due in part to the phosphorylation of critical amino acids in the RXRα AF-1 domain and impaired co-activator recruitment. J. Cell. Physiol. 224: 433–442, 2010. © 2010 Wiley-Liss, Inc.
The perfect landscape

The “perfect storm” metaphor describes the improbable coincidence of several different forces or factors to produce an unusual outcome. The perfect landscape is conceptualized as a result of the combined, interacting effects of multiple environmental controls and forcings to produce an outcome that is highly improbable, in the sense of the likelihood of duplication at any other place or time. Geomorphic systems have multiple environmental controls and forcings, and degrees of freedom in responding to them. This allows for many possible landscapes and system states. Further, some controls and forcings are causally contingent. These contingencies are specific to time and place. Dynamical instability in many geomorphic systems creates and enhances some of this contingency by causing the effects of minor initial variations and small disturbances to persist, and grow disproportionately large, over time. The joint probability of any particular set of global controls is low, as the individual probabilities are <1, and the probability of any set of local, contingent controls is even lower. Thus, the probability of existence of any landscape or earth surface system state at a particular place and time is negligibly small: all landscapes are perfect. Recognition of the perfection of landscapes leads away from a worldview holding that landforms and landscapes are the inevitable outcomes of deterministic laws, such that only one outcome is possible for a given set of laws and initial conditions. A perfect landscape perspective leads toward a worldview that landforms and landscapes are circumstantial, contingent results of deterministic laws operating in a specific environmental context, such that multiple outcomes are possible.
comment on Eugene Cooper's «cousin marriage in rural China»

Alors que D. M. Schneider critique l'article de E. Cooper sur le mariage entre cousins en Chine du fait que celui-ci tente d'expliquer un fait social en terme de motivations psychologiques, E. Cooper repond a cette attaque en mettant en avant le fait qu'il a voulu lier les approches structurelle et behavioriste
Using noble gases measured in spring discharge to trace hydrothermal processes in the Norris Geyser Basin, Yellowstone National Park, U.S.A.

Abstract Dissolved noble gas concentrations in springs are used to investigate boiling of hydrothermal water and mixing of hydrothermal and shallow cool water in the Norris Geyser Basin area. Noble gas concentrations in water are modeled for single stage and continuous steam removal. Limitations on boiling using noble gas concentrations are then used to estimate the isotopic effect of boiling on hydrothermal water, allowing the isotopic composition of the parent hydrothermal water to be determined from that measured in spring. In neutral chloride springs of the Norris Geyser Basin, steam loss since the last addition of noble gas charged water is less than 30% of the total hydrothermal discharge, which results in an isotopic shift due to boiling of ≪ 2.5‰ δD. Noble gas concentrations in water rapidly and predictably change in dual phase systems, making them invaluable tracers of gas–liquid interaction in hydrothermal systems. By combining traditional tracers of hydrothermal flow such as deuterium with dissolved noble gas measurements, more complex hydrothermal processes can be interpreted.
Combinatorial materials research applied to the development of new surface coatings XI: a workflow for the development of hybrid organic–inorganic coatings

Interest in hybrid organic–inorganic (HOI) materials has grown rapidly in the last two decades. The appeal of this broad class of materials can be attributed to the unique combinations of properties that can be achieved by combining an inorganic phase with an organic phase. HOI materials can be divided into two basic categories: homogeneous systems derived from monomers or miscible organic and inorganic components, and heterogeneous, phase-separated systems with domains ranging from angstroms to micrometers in size. The structure of the inorganic component is dependent on the interaction of many variables such as pH, water content, overall solution concentration, solvent composition, temperature, and time. Due to the complexity of HOI materials, a combinatorial/high-throughput approach to the development of novel materials is highly desired. The authors have recently developed a combinatorial workflow for the synthesis and characterization of HOI coatings. Initial experimentation conducted with the workflow was focused on the development of primers for corrosion protection derived from a HOI binder system and magnesium particles. Both the homogeneous and heterogeneous HOI binders were investigated. With just one iteration of the combinatorial workflow, heterogeneous, moisture-curable HOI binders were identified, which enabled the formation of magnesium-rich primers that provided excellent corrosion protection to an aerospace aluminum alloy (Al 2024).
Eficàcia i eficiència de la pollinització d'abellots i colibrís que visiten Delphinium nelsonii

Delphinium nelsonii Greene is a spring-flowering perennial of the Rocky Mountains of North America. Its blue flowers conform to a classical «bee pollination syndrome», but in western Colorado they are visited by hummingbirds (mostly in the first half of the flowering season) as well as bumble bee queens (mostly in the second half of the season). Experiments with potted plants showed that a bee deposits about 10 times as much pollen while visiting a flower as does a bird, and causes about la times as many seeds to be set. In contrast, bees and birds appear similar in the «quality» of pollen they deliver, e. g., in its outcrossing distance. At the level of entire pollinator populations, hummingbird visitation rates may be over 10 times as great as those or bumble bees, in part because birds visit flowers more quickly. Thus the two visitor classes should deliver similar pollen quantities overall, which is confirmed by similar pollen loads of flowers early and late in the season, and should contribute about equally to seed set, which is confirmed by several experiments and observations. Exact relative contributions probably depend on pollinator population sizes, which in the case of hummingbirds appear to have varied 2.5 fold across 14 years. The similar contributions or birds and bees lo seed set shows that individual pollination efficiency must be distinguished from population-level effectiveness. and that the «pollination syndrome» of a flower may not indicate present-day effectiveness of its visitors.
Perceptions of teachers, students and parents of the characteristics of good teachers: a cross-cultural comparison of China and the United States

Since the 1920’s many researchers have conducted studies exploring the qualities of good teachers. However, a limited number of empirical studies have been conducted in the People’s Republic of China (hereafter called China). The current study has two objectives. The first one aims to compare a good teacher’s characteristics in China and the USA. To achieve this, qualitative data of a good teacher’s characteristics were collected in China. The results obtained from China were then compared to those reported in the USA. The second objective was to test whether or not there are differences among teachers’, students’ and parents’ perceptions of a good teacher’s characteristics in China. To achieve this, questionnaires were administered, and then statistical analyses were conducted. The qualitative data analyses have revealed four themes about the characteristics of good Chinese teachers: Teacher ethics, professional skills, professional development, and students’ test scores. The ANOVAs have found no differences among teachers’, students’ and parents’ perceptions of the qualities of good teachers in China on most of the items. This study helps readers better understand good teachers in a Chinese context and provides a framework for future comparative study between China and the USA regarding the qualities of good teachers.
University Students' Reading of Their First-Year Mathematics Textbooks.

This article reports the observed behaviors and difficulties that 11 precalculus and calculus students exhibited in reading new passages from their mathematics textbooks. To gauge the effectiveness of these students' reading, we asked them to attempt straightforward mathematical tasks, based directly on what they had just read. The students had high ACT mathematics and high ACT reading comprehension test scores and exhibited much of the Constructively Responsive Reading of good readers as described in the reading comprehension research literature. However, they were not effective readers of their mathematics textbooks. We discuss some reasons for this that might not be easily discernible among the variety of task-working difficulties of less able students. Finally, we pose questions for future research and suggest some implications for teaching.
FOUNDATION ON STRONG SAND UNDERLAIN BY WEAK CLAY WITH GEOGRID AT THE INTERFACE

Abstract A number of laboratory model test results for the ultimate bearing capacity of a surface strip foundation supported by a strong sand layer of limited thickness underlain by a weak clay with a layer of geogrid at the sand-clay interface has been presented. The tests were conducted at one relative density of compaction of sand and one undrained shear strength of clay. Two types of geogrid were used. Based on the model test results presented, it appears that the optimum height of the strong sand layer should be about two-thirds that of the foundation width for obtaining the maximum benefit from the geogrid reinforcement.
Pseudomonas aeruginosa Porin OprF Exists in Two Different Conformations

The major nonspecific porin of Pseudomonas aeruginosa, OprF, produces a large channel yet allows only a slow diffusion of various solutes. Here we provide an explanation of this apparent paradox. We first show, by introduction of tobacco etch virus protease cleavage site in the middle of OprF protein, that most of OprF population folds as a two-domain protein with an N-terminal β-barrel domain and a C-terminal periplasmic domain rich in α-helices. However, sedimentation of unilamellar proteoliposomes through an iso-osmotic gradient showed that only about 5% of the OprF population produced open channels. Gel filtration showed that the open channel conformers tended to occur in oligomeric associations. Because the open channel conformer is likely to fold as a single domain protein with a large β-barrel, we reasoned that residues near the C terminus may be exposed on cell surface in this conformer. Introduction of a cysteine residue at position 312 produced a functional mutant protein. By using bulky biotinylation reagents on intact cells, we showed that this cysteine residue was not exposed on cell surface in most of the OprF population. However, the minority OprF population that was biotinylated in such experiments was enriched for the conformer with pore-forming activity and had a 10-fold higher pore-forming specific activity than the bulk OprF population. Finally trypsin treatment, which preferentially cleaves the C-terminal domain of the two-domain conformer, did not affect the pore-forming activity of OprF nor did it digest the minority conformer whose residue 312 is exposed on cell surface.
Comments on "A stochastic automaton model for the synthesis of learning systems"

This correspondenice attempts to point out the invalidity of a convergesnce property asserted by R.W. McLaren (ibid., vol. SSC-2, pp. 109-114, December 1966) for a stochastic automaton model for learning systems. The error results from ani erronieous derivation of eq. (18) from eq. (17).
Multidimensional Finite Differencing (MDFD) with Hypersphere-Close-Pack Grids

ABSTRACT This article concerns the use of hypersphere-close-pack (HCP) grids and quadratic multivariate Taylor polynomial interpolation functions with several additional higher-order terms for multidimensional finite differencing (MDFD). MDFD is a general methodology for the numerical solution of partial differential Equations (PDE) defined on irregular domains. MDFD uses domain embedding, which means that expensive body-fitted gridding is not required, but the methodology is flexible enough to allow any grid. The HCP grid allows efficient, stable, and robust implementation of MDFD. In this article, we discuss MDFD and related methods, summarize the HCP grids in two and three dimensions, outline the algorithms used, and present the results of a number of diagnostic examples. The examples concern numerical solution of the unsteady parabolic heat equation defined for a number of domains of different shapes. The examples suggest, among other things, that the algorithms work with domains that have no similari...
Using the modified embedded-atom method to calculate the properties of Pu-Ga alloys

In this article, the semi-empirical modified embedded atom method is used to develop a model of Pu-Ga alloys. Employing classical calculations, the model is used to predict thermodynamic properties of these alloys as well as the complex Pu-Ga phase diagram.
Abstract IA2: The molecular basis of tumor immunogenicity.

Cancer Immunoediting is the process by which the immune system controls and shapes cancer. We originally envisaged that cancer immunoediting would occur in three phases: Elimination (also known as cancer immunosurveillance, the host protective phase of the process), Equilibrium (the phase in which tumor cells that survive immune elimination remain under immunologic growth control resulting in a state of functional tumor dormancy) and Escape (the phase where clinically apparent tumors emerge because immune sculpting of the tumor cells has produced variants that display either reduced immunogenicity or enhanced immunosuppressive activity). Strong experimental data has now been obtained using mouse models of cancer to demonstrate the existence of each phase of the cancer immunoediting process and compelling clinical data suggests that a similar process may also occur during the evolution of certain types of human cancer. Our efforts now focus on elucidating the molecular and cellular mechanisms that underlie each phase of cancer immunoediting and identifying the critical checkpoints that regulate progression from one phase of the process to the next. This approach has helped identify the nature of antigens seen by immunity in nascent developing cancers and has further shown that immunoselection is a major mechanism of immunoediting. Moreover, we have found that edited tumors can still be controlled by the immune system if natural mechanisms that prevent autoimmunity are suspended. As reported by others, we have confirmed that inhibition of CTLA-4 induces ejection of edited MCA sarcomas. However, we have also found that inhibition of PD-L1 does the same, although by perhaps different mechanisms. These differences will be discussed. Citation Format: Robert D. Schreiber. The molecular basis of tumor immunogenicity. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology: Multidisciplinary Science Driving Basic and Clinical Advances; Dec 2-5, 2012; Miami, FL. Philadelphia (PA): AACR; Cancer Res 2013;73(1 Suppl):Abstract nr IA2.
An experimental manipulation of food and water: growth and time-space utilization of hatchling lizards (Sceloporus undulatus)

At a site in western Nebraska, we studied the effects of supplemental food and water on growth, survival, and habitat utilization of hatchling iguanid lizards, Sceloporus undulatus. Hatchlings were randomly assigned to one of four experimental groups and received either (1) supplemental food only, (2) supplemental water only, (3) supplemental food and water, or (4) neither supplemental food nor water (control). Neither supplemental food nor supplemental water affected growth rate in length, growth rate in mass, or size-specific body mass (i.e. robustness) at the end of the treatment period. Over the 45 day treatment pierod, there were no significant differences among treatment groups in survival, home-range size, or habitat utilization. There were, however, significant differences in the index of activity. Hatchlings in the treatment groups receiving supplemental water were sighted more often than hatchlings in the control group. We conclude that, during our study, neither food nor water limited growth but that water limited activity.
The relationship between perception and production of /w/, /r/, and /l/ by three-year-old children

Abstract Twenty-one normally developing 3-year-old children were tested on two approximant consonant contrasts, rake-lake and wake-rake , and a control contrast, wake-bake . Perception was assessed in a two-choice picture identification paradigm; stimuli were (1) natural and computer synthesized “clear cases” of the minimal pairs, and (2) synthetic stimulus series which interpolated on acoustic dimensions that differentiate the minimal pairs. As a group, the children showed very accurate perception of the minimal pairs. Performance on the synthetic series yielded consistent identification of the endpoint stimuli and monotonic functions with abrupt crossovers at the phoneme boundary. Children who did not yet articulate /r/ and /l/ appropriately showed somewhat less consistent perception than children who produced all phonemes correctly.
Bullous Skin Lesions Associated With Yersinia Enterocolitica Septicemia

An 86-year-old woman developed large bullae on both legs during the course of septicemia due to Yersinia enterocolitica. Although erysipelas-like lesions and erythema nodosum have been known to be associated with Yersinia infections, this is the first reported case with multiple bullae.
A 75 GHz silicon metal‐semiconductor‐metal Schottky photodiode

The ultrafast characteristics of crystalline‐silicon metal‐semiconductor‐metal (MSM) photodiodes with 300 nm finger width and spacing were measured with a subpicosecond electro‐optic sampling system. Electrical responses with full width at half maximum as short as 5.5 and 11 ps, at corresponding 3 dB bandwidths of 75 and 38 GHz, were generated by violet and red photons, respectively. The difference is attributed to the photon penetration depth which is much larger than the diode finger spacing at red, but smaller at violet. Light‐intensity dependence was also examined at different wavelengths, indicating a linear relation and a higher sensitivity in the violet. These results not only demonstrated the fastest silicon photodetector reported to date, but also pinpointed the dominant speed‐limiting factor of silicon MSM photodiodes. A configuration is suggested to improve the speed of these detectors at long wavelengths.
Microfluidic Formation of Hydrogel Microparticles for Drug Delivery

Creating monodispersed hydrogel microparticles is advantageous for drug delivery applications. We explore microfluidic flow focusing as a method for generating such particles. Our hydrogel has a unique composition that makes it biodegradable and mechanically strong. We designed and manufactured a polymer microfluidic chip that mixes three viscous precursor solutions and generates a steady stream of microparticles from that solution. We found that microfluidic flow focusing produce particle with a coefficient of variance around 9%; this was a four times improvement over traditional methods.© 2010 ASME
A new cryptomonad from antarctica: Cryptomonas cryophila sp. nov.

A taxonomic diagnosis of Cryptomonas cryophila sp. nov. (Cryptophyceae) is given, and its ultrastructural morphology is described. Although isolated from beneath Antarctic sea ice, its fine structure differs little from that described for related species. The principal distinguishing features is the possession of paired, stalked pyrenoids, which have an unusual kidney-like morphology.
An Examination of the Effects of Accountability when Auditors are Uncertain about the Views of Superior Partners

This experiment focused on the effect of accountability on senior audit managers' reporting decisions related to ambiguous scenarios, where the auditors could only speculate on the views of superior auditors on specific reporting issues. It examines the potential effect of accountability on the relationship between judgments an auditor would make versus the judgments the auditor perceives superior partners would make. In particular, accountable auditors were predicted to engage in a hybrid strategy of processing information with more effort and of complying more with views they perceived to be held by the superiors. Consistent with the acceptability heuristic, the results indicate that accountability is associated with greater agreement between self-judgments and judgments the auditor perceives superiors would make. However, contrary to Tetlock's (1992) theory but consistent with some prior research (Johnson and Kaplan, 1991; Hoffman and Patton, 1997), the accountability treatment did not significantly affect the auditors' processing of information.
Perinatal manipulation of α-linolenic acid intake induces epigenetic changes in maternal and offspring livers

Previous studies indicated that the intake of α-linolenic acid (ALA) can alter the concentration of both ω-6 and ω-3 fatty acids in both mother and offspring, with consequences on postnatal brain development. This study describes the association between maternal ALA availability during gestation and lactation, and alterations in the Fads2 DNA methylation in both maternal and offspring livers, at the end of lactation period. Both Fads2 promoter and intron 1 DNA methylation were increased in the groups receiving postnatal flaxseed oil containing 50% ALA (mothers or pups), while bivariate analysis indicated a significant association of the Fads2 epigenetic status in the liver between each mother and its offspring. In addition, Fads2 expression was negatively correlated with promoter methylation at the individual level in maternal livers (P<0.05). This study also indicated that the interplay between ALA availability during gestation and lactation can differentially alter the expression of desaturases and elongases involved in ω-6 and ω-3 metabolic pathways. In summary, when considering the perinatal dietary ALA requirements in mice, both gestation and lactation periods should be considered as having distinct roles in modulating the metabolism of ω-6 and ω-3 fatty acids in maternal mouse livers.
Superabundant Food at Catfish Aquaculture Facilities Improves Body Condition in American White Pelicans

Abstract. Few studies have investigated the use of aquaculture-produced foods by piscivorous birds. American White Pelicans (Pelecanus erythrorhynchos) were collected from four locations (two aquaculture, one riverine and one coastal) in the southeastern United States during winter and spring 1998–1999 to assess the contribution (biomass, frequency of occurrence) of aquaculture-produced foods and their effect on body condition. Pelican diets reflected opportunistic foraging across locations. Diet near catfish ponds consisted mostly of Channel Catfish (Ictalurus punctatus). Diets along the Mississippi River had similarly high biomass of catfish, but otolith counts suggested lower use of catfish. Diets near crawfish (Procambarus spp.) ponds included shad (Dorsomis spp.), crawfish and sunfish (Lepomis spp.); whereas diets from coastal Louisiana were predominantly salt water fish. Pelican body condition, as indexed by percent omental fat, was similar between seasons but higher at catfish ponds. Foraging at cr...
Novel gene expression patterns in hybrid embryos between species with different modes of development

SUMMARY Cross-species hybrids between eggs of the direct-developing sea urchin, Heliocidaris erythrogramma, and sperm from its congeneric indirect-developing species, Heliocidaris tuberculata, show restoration of features of the paternal feeding pluteus larva, including the gut, and pluteus spicular skeleton. Unlike other reported sea urchin cross-species hybrids, Heliocidaris hybrids express genes derived from both maternal and paternal species at high levels. Ectodermal cell types, which differ radically between the two parental species, are of intermediate form in the hybrids. Gene expression patterns in hybrid embryo tissues represent a number of combinations of parental gene expression patterns: genes that are not expressed in one paternal species, but are expressed in hybrids as in the expressing parent; genes that show additive expression patterns plus novel sites of expression; a gene that is misexpressed in the hybrids; and genes expressed identically in both parents and in hybrids. The results indicate that both conserved and novel gene regulatory interactions are present. Only one gene, CyIII actin, has lost cell-type-specific regulation in the hybrids. Hybrids thus reveal that disparate parental genomes, each with its own genic regulatory system, can produce in combination a novel gene expression entity with a unique ontogeny. This outcome may derive from conserved gene regulatory regions in downstream genes of both parental species responding in conserved ways to higher-level regulators that determine modular gene expression territories.
Pathologic changes in the blood of the greater wax moth, Galleria mellonella, during the course of nucleopolyhedrosis and starvation II. Differential hemocyte count

Abstract In larvae inoculated with nucleopolyhedrosis virus and fed a normal diet, no change was observed in the total hemocyte count (THC) until day 10, when a significant decrease was detected. The THC's increased in control larvae but decreased in starved larvae. Within the first 5 days of the test the THC's in inoculated larvae were significantly higher than in starved larvae but were significantly lower than in control larvae.
Narcolepsy in a 7-year-old child.

R E F E R E N C E S 1. Pliam MB, McGough EC, Nixon GW, et al: Right atrial ball-valve thrombus: A complication of central venous alimentation in an infant. J Thorac Cardiovasc Surg 78:579, 1979. 2. Firor HV: Pulmonary embolization complicating total intravenous alimentation. J Pediatr Surg 7;81, 1972. 3. Wesley JR, Keens TG, Miller SW, Platzker ACG: Pulmonary embolism in the neonate: Occurrence during the course of total parenteral nutrition. J PEDIATR 93:113, 1978. 4. Mahoney L, Snider AR, Silverman NH: Echocardiographic diagnosis of intracardiac thrombi complicating total parenteral nutrition. J PEDIATR 98:469, 1981. 5. Sharma GVRK, Celia G, Parisi AF, Sasahara AA: Thrombolyric therapy. N Engl J Med 306:1268, 1982. 6. Delaplane D, Scott JP, Riggs TW, et al: Urokinase therapy for a catheter-related right atrial thrombus. J PEDIA'VR 100:149, 1982. 7. Nazzaro MP, Passi S, Caprilli F, et al: Growth requirements and lipid metabolism of Pityrosporum orbiculare. J Invest Dermatol 66:178, i976. 8. Redline RW, Dahms BB: Malassezia pulmonary vasculitis in an infant on long-term Intralipid therapy. N Engl J Med 305:1395, ]981. 9. Wallace M, Bagnall H, Glen D, Averill S: Isolation of lipophilic yeast in "sterile" peritonitis. Lancet 2:956, 1979.
Chemical bonding and the incorporation of potassium into the Earth's core

It has been argued that most of the Earth's potassium was segregated into the outer core and that the radioactive decay of 40K provided the heat source for the geodynamo. This idea rests on the assumption that the affinity of potassium for sulfur or metallic iron is enhanced at high pressure. In this paper, the high pressure electronic structures of K in sulfide, iron sulfide and metallic iron coordination environments were determined from molecular orbital (SCF-Xα-SW) calculations on (KS8)15−, (KS8Fe6)3− and KFe14 clusters. It is shown that, even at high pressure, potassium cannot alloy with metallic iron. Although a high-pressure electronic transition may enhance the potassium-sulfur chemical bond, the electronic structure of the KS8Fe6 cluster shows that this electronic transition cannot happen in an iron sulfide melt. Consequently, potassium will not have an enhanced affinity for sulfur in planetary interiors. If the lower mantle were more reducing, potassium might be excluded from the silicate phases by more strongly lithophile elements and segregated into a metal sulfide phase in the outer core (cf. the phase assemblages in enstatite chondrites). Given the oxidation state of the Earth, however, it is unlikely that significant quantities of potassium have been incorporated into the outer core. The Earth, like the moon and the eucrite parent body, is depleted in potassium. An alternative heat source (e.g., the radioactive decay of U and Th) must be invoked to explain the geodynamo.
Medical leadership and the future of health care

Abstract Introduction of Doctor Shore by President Richard P. Anderson It is my pleasure at this time to introduce the Ralph Alley lecturer. You will notice in your program that this lecture is supported by a grant from the Cardiothoracic Research and Education Foundation of Spartanburg, South Carolina. This is a private foundation created by one of our own members, Dr Joe R. Utley. Joe is presently recovering from a severe illness and can't be with us, and we certainly wish him a speedy return to good health. Dr Ralph D. Alley, for whom this lecture is named, was not only a founder of this Society but he served as a mentor to most of the officers and many of the members over a period of 20 years. As both an inspiring teacher and a humanist, I believe that he would approve heartily of our lecturer this year, who is Dr Miles Shore. Doctor Shore is a psychiatrist. He was educated at the University of Chicago in undergraduate work and then subsequently at Harvard University. His distinguished career in mental health includes both clinical and administrative appointments at Tufts University School of Medicine and at Harvard University. He is presently Professor of Psychiatry and Director of the Division of Mental Health Systems at Harvard. In 1993 he was appointed visiting scholar at the Kennedy School of Government at Harvard, and in 1996, together with Dr Joseph Newhouse, Jack M. Matloff, and other members of this Society, he created the Health Policy Executive Program, Understanding the New World of Health Care. Subsequently, he has served as an enthusiastic director of that course. His particular interests are health policy and leadership. Those of us fortunate enough to have heard his lectures are impressed with both his scholarship and his insight into human behavior. As we approach the new century, there is no better guide to the complex world that health care has become than Miles.
Fate of mitral regurgitation after aortic valve replacement for aortic stenosis.

A75-YEAR-OLD MAN with dizziness and shortness of breath underwent a balloon valvuloplasty performed for critcal aortic stenosis. After experiencing minimal symptomatic reief, the patient presented to the authors’ tertiary care center with orsening symptoms 2 weeks after the procedure. The patient’s istory was significant for congestive heart failure, type-2 diabetes ellitus, coronary artery disease, chronic atrial fibrillation, and ypertension, and he had undergone a coronary artery bypass graft rocedure in 1992. Because of a lack of symptomatic improveent after balloon valvuloplasty and persistence of decompenated congestive heart failure, despite his high risk, it was decided o perform aortic valve replacement (AVR). After an uneventful induction of general anesthesia, a re– cardiopulmonary bypass (CPB) transesophageal echoardiographic (TEE) examination was performed; an AV rea of 0.5 cm2 (critical 0.8 cm2) was calculated with the
Orthogonal Gough-Stewart platforms for micromanipulation

Development of methods to design optimal Gough-Stewart platform geometries capable of meeting desired specifications is of high interest. Computationally intensive methods have been used to treat this problem in various settings. This paper uses analytic methods to characterize all orthogonal Gough-Stewart platforms (OGSPs) and to study their properties over a small workspace. This characterization is used to design optimal OGSPs for precision applications that achieve a desired hyperellipsoid of velocities. Some examples demonstrating the versatility of this theory are discussed.
A SiC MEMS Resonant Strain Sensor for Harsh Environment Applications

In this paper, we present a silicon carbide MEMS resonant strain sensor for harsh environment applications. The sensor is a balanced-mass double-ended tuning fork (BDETF) fabricated from 3C-SiC deposited on a silicon substrate. The SiC was etched in a plasma etch chamber using a silicon oxide mask, achieving a selectivity of 5:1 and etch rate of 2500 Aring/min. The device resonates at atmospheric pressure and operates from room temperature to above 300degC. The device was also subjected to 10 000 g shock (out-of-plane) without damage or shift in resonant frequency. The BDETF exhibits a strain sensitivity of 66 Hz/muepsiv and achieves a strain resolution of 0.11 muepsiv in a bandwidth from 10 to 20 kHz, comparable to state-of-the-art silicon sensors
Selective sentinel lymph node dissection in head and neck cutaneous melanoma

Sentinel lymph node biopsy accuracy and prognostic value in the head and neck region has been established. The article describes the current indications for the procedure, lymph node localization using lymphoscintigraphy and intra-operative blue dye injection, the surgical technique, and important recommendations to avoid complications in this very important anatomic region.
A PORPOISE FOR POWER

![Graphic][1] Frank Fish writes about James Gray's 1936 publication on the power output of a swimming dolphin . Sometimes the most innocent of scientific endeavors can have the most far-reaching and profound ramifications. For James Gray, a simple calculation to determine the power output
In vivo gene silencing (with siRNA) of pulmonary expression of MIP-2 versus KC results in divergent effects on hemorrhage-induced, neutrophil-mediated septic acute lung injury

Lung injury in trauma patients exposed to a secondary infectious/septic challenge contrib- utes to the high morbidity/mortality observed in this population. Associated pathology involves a dys-regulation of immune function, specifically, se- questration of activated polymorphonuclear neu- trophils (PMN) in the lungs. The targeting of PMN is thought to involve the release of chemokines from cells within the local environment, creating a concentration gradient along which PMN migrate to the focus of inflammation. Keratinocyte-derived chemokine (KC) and macrophage-inflammatory protein-2 (MIP-2) are murine neutrophil chemo- kines identified as playing significant but potentially divergent roles in the pathogenesis of acute lung injury (ALI). In the current study, we examined the contribution of local pulmonary cells to the pro- duction of KC and MIP-2 and the pathogenesis of ALI. We hypothesized that local silencing of KC or MIP-2, via the local administration of small inter- ference RNA (siRNA) against KC or MIP-2, follow- ing traumatic shock/hemorrhage (Hem), would suppress signaling for PMN influx to the lung, thereby reducing ALI associated with a secondary septic challenge (cecal ligation and puncture). As- sessment of siRNA local gene silencing was done in green fluorescent protein (GFP)-transgenic, over- expressing mice. A marked suppression of GFP expression was observed in the lung 24 h following intratracheal (i.t.) instillation of GFP siRNA, which was not observed in the liver. To test our hypoth- esis, siRNA against KC or MIP-2 (75 ug/C3H/Hen mouse) was instilled (i.t.) 2 h post-Hem (35 mm Hg for 90 min, 4 LRS Rx.). Twenty-four hours after, mice were subjected to septic challenge and then killed 24 h later. i.t. MIP-2 siRNA significantly (P<0.05, ANOVA-Tukey's test, n5-6/group) re- duced tissue and plasma interleukin (IL)-6, tissue MIP-2 (enzyme-linked immunosorbent assay), as well as neutrophil influx (myeloperoxidase (MPO) activity). In contrast, KC siRNA treatment reduced plasma KC, tissue KC, and IL-6 but produced no significant reduction in plasma IL-6 or MPO. Nei- ther treatment reduced tissue or plasma levels of tumor necrosis factor compared with vehicle. These data support not only our hypothesis that local pulmonary chemokine production of MIP-2, to a greater extent than KC, contributes to the pathogenesis of PMN-associated ALI following Hem but also the use of siRNA as a potential therapeutic. J. Leukoc. Biol. 77: 000-000; 2005.
The Ultra Heavy Elements in the Cosmic Radiation

The concept that nuclei of all of the elements in the periodic table were accelerated to relativistic energies in the primary cosmic rays was confirmed by the discovery of the presence of nuclei significantly heavier than iron. These “ultra heavy” nuclei must all have been synthesized in endothermic reactions, occurring predominately in the final stages of stellar evolution. Determination of the relative abundances of these nuclei should provide new insights into the nuclear processes in some of the most energetic events in the life cycle of stars. The very low abundances of these nuclei relative to those of the exothermic lighter nuclei have made progress difficult. In addition, the effects of apparent preferential acceleration mechanisms and of propagation through the interstellar medium have distorted the source abundances. The history of the original discovery of the presence of these nuclei will be followed by a summary of the present state of knowledge of the observed abundances. The effects of acceleration biases and of interstellar propagation will be discussed. Finally some of the possibilities for further advances will be outlined.
Target heat loading due to fast, transient heat pulses produced from a conical θ-pinch as a prototype for benchmarking simulations of transient heat loads

Abstract The ELM simulating plasma gun (ESP-gun) has been developed to study the effects of transient, blob-like plasmas on the plasma facing components of TOKAMAKs. ESP-gun utilizes a RF helicon plasma to pre-ionize a plasma column underneath a conical, θ-pinch coil, which is used to compress and eject plasmas. Measurements have been made of the existing RF plasma and the subsequent compressed plasma. A copper target was placed downstream of the θ-pinch, and its temperature rise was measured with respect to time. For modest argon plasmas, ne ∼ 1018 m−3 and Te ⩽ 100 eV, the target temperature was observed to have an equivalent heat loading of up to 90 kJ/m2. Given that the plasma density and temperature are low, it is believed that the target heat loading will scale linearly with plasma density such that plasmas of 1020–1021 m−3 would reach target heat loading in excess of 1 MJ/m2. A zero dimensional thermal model will be presented to estimate the expected target heat loading.
Label-free imaging of cancer cells using photonic crystal biosensors and application to cytotoxicity screening of a natural compound library

A rapid and accurate quantitative method for screening the effects of drug compounds upon cells utilizing label-free photonic crystal optical biosensors incorporated within 96-well microplates is described. The biosensors and associated imaging detection instrument enable visualization and quantitative measurement of cell populations attached to the sensor surface with sensitivity sufficient for the detection of individual cells without the use of labels or stains that typically induce the death of the cells under study. The detection method allows repeated measurement of the same cells without removing them from their culture environment, and thus allows direct determination of proliferation and apoptosis rates. In this work, a biosensor-based cell assay is used to screen the effect of a 61-member compound library of plant extracts upon human breast cancer cells, in which some members of the library are shown to induce apoptosis, while others increase the rate of cancer cell proliferation. The results are broadly applicable to a wide range of cell types and compounds, while the assay is simpler and more rapid than alternative apoptosis/proliferation assays.
Erk1 and Erk2 Regulate Endothelial Cell Proliferation and Migration during Mouse Embryonic Angiogenesis

Angiogenesis is a complex process orchestrated by both growth factors and cell adhesion and is initiated by focal degradation of the vascular basement membrane with subsequent migration and proliferation of endothelial cells. The Ras/Raf/MEK/ERK pathway is required for EC function during angiogenesis. Although in vitro studies implicate ERK1 and ERK2 in endothelial cell survival, their precise role in angiogenesis in vivo remains poorly defined. Cre/loxP technology was used to inactivate Erk1 and Erk2 in endothelial cells during murine development, resulting in embryonic lethality due to severely reduced angiogenesis. Deletion of Erk1 and Erk2 in primary endothelial cells resulted in decreased cell proliferation and migration, but not in increased apoptosis. Expression of key cell cycle regulators was diminished in the double knockout cells, and decreased DNA synthesis could be observed in endothelial cells during embryogenesis. Interestingly, both Paxillin and Focal Adhesion Kinase were expressed at lower levels in endothelial cells lacking Erk1 and Erk2 both in vivo and in vitro, leading to defects in the organization of the cytoskeleton and in cell motility. The regulation of Paxillin and Focal Adhesion Kinase expression occurred post-transcriptionally. These results demonstrate that ERK1 and ERK2 coordinate endothelial cell proliferation and migration during angiogenesis.
Switchbox routing with movable terminals

The switchbox routing problem (SRP) in which terminals have some flexibility in placement on the border is considered. The general problem with position constraints is NP-complete, as is the problem with only order constraints or separation constraints. The problem is solved for the case in which terminals are permutable within prespecified groups of adjacent vertices, called clusters. Whenever possible, the algorithm determines a terminal assignment such that the resulting SRP is solvable; the total time to assign the terminals and to construct a layout is O(N log N), where N is the number of nets. The results extend to multiple layers and to convex grids. >
Effectiveness of thrice weekly ezetimibe.

Ezetimibe is usually dosed daily, but its 22-hour elimination half-life permits significant cholesterol reduction with less frequent dosing. The aim of this study was to examine lipid changes in 33 patients treated with thrice-weekly ezetimibe for ≥1 month, who had pre- and postezetimibe lipid levels and no other concurrent changes in their lipid treatment. Ninety-four percent of the patients were treated with ezetimibe because they experienced myalgias, elevated transaminase levels, or gastrointestinal intolerance with higher doses of other lipid-lowering agents. Total cholesterol decreased by 15% (−36 ± 28 mg/dl, p
Controlling Quality of Service in Multi-Tier Web Applications

The need for service differentiation in Internet services has motivated interest in controlling multi-tier web applications. This paper describes a tier-to-tier (T2T) management architecture that supports decentralized actuator management in multi-tier systems, and a testbed implementation of this architecture using commercial software products. Based on testbed experiments and analytic models, we gain insight into the value of coordinated exploitation of actuators on multiple tiers, especially considerations for control efficiency and control granularity. For control efficiency, we show that more effective utilization of tiers can be achieved by using actuators on the bottleneck tier rather than only using actuators on the entry tier. For granularity of control (the ability to achieve a wide range of service level objectives) we show that a fine granularity of control can be achieved through a coordinated, cross-tier exploitation of coarse grained actuators (e.g., multiprogramming level), an approach that can greatly reduce controllerinduced variability.