cssi/SciSciGPT-SciSciNet huggingface dataset:
Does medical school performance predict radiology resident performance

Abstract Rationale and Objectives The authors performed this study to examine the relationship, if any, of a large number of measures of medical school performance with radiology residency performance. Materials and Methods Applications of 77 radiology residents enrolled from 1991 to 2000 were reviewed. Medical school grades, dean's letter summary statements, letters of recommendation, selection to Alpha Omega Alpha (AOA), and National Board of Medical Examiners (NBME) and U.S. Medical Licensing Examination (USMLE) Step 1 scores were recorded. Student t tests, analysis of variance, and correlation coefficients were used to examine the relationship between these measures of medical school performance and subsequent performance during radiology residency as determined by rotation evaluations, retrospective faculty recall scores, and American College of Radiology (ACR) and American Board of Radiology (ABR) examination scores. Resident performance was also correlated with prestige of the medical school attended. Results Preclinical grades of Honors or A; clinical grades of Honors or A in medicine, surgery, and pediatrics; and high NBME/USMLE scores strongly predicted success on the ABR written clinical examination but did not predict rotation performance. Most other measures of medical school performance, including outstanding Dean's letters and letters of recommendation, AOA selection during the senior year, and high medical school prestige did not predict high examination scores or superior rotation performance during residency. Conclusion Success on the ABR examination can be predicted by medical school success in preclinical courses, some clinical courses, and USMLE examination scores. Dean's letters, letters of recommendation, AOA selection during the senior year, and medical school prestige do not appear to predict future resident performance as reliably.
Child physical and sexual abuse and cigarette smoking in adolescence and adulthood.

Purpose Analyses used data from an extended longitudinal study to examine the relationship between childhood physical and sexual abuse (CPA and CSA, respectively) and adolescent and adult smoking behavior. Two questions guided the study: (1) Is there an association between childhood abuse and adolescent and adult smoking behavior? (2) Does the relationship between childhood abuse and later cigarette smoking differ for males and females?
A one pot synthesis unsymmetric secondary alcohols from two grignard reagents

Abstract The sequential addition of two Grignard reagents to 2-(N-methyl-N-formy)-amino-pyradine in tetrahydrofuran provides a high yield one pot synthesis of unsymmetrical secondary alcohols.
Teichmüller contraction in the Teichmüller space of a closed set in the sphere

We generalize the principle of Teichmuller contraction and deduce the Hamilton-Krushkaĺ condition for extremal quasiconformal mappings in the Teichmuller space of a closed set in the Riemann sphere.
Methylmethacrylate onlay implants in the treatment of forehead deformities secondary to craniosynostosis.

Summary Craniosynostosis ( Cruzon's, Pfeiffer's and Apert's Syndrome, etc.) can cause forehead deformities that frequently need reconstruction. In general, osteotomies and/or bone grafting are the preferred methods for obtaining proper orbital protection from above and a good aesthetic appearance. In certain cases however, osteotomies and/or bone grafting are not possible or a patient may refuse to have such an extensive procedure. Preformed methylmethacrylate prostheses have in such cases been implanted in patients with significant skull deformities with only minimal morbidity. The ease of this technique coupled with the shortened operative time, minimal hospitalization, and few, minor complications offer the reconstructive surgeon another and relatively simple method for treatment of extensive forehead and supraorbital deformities.
Efficient Pseudospectral Flow Simulations in Moderately Complex Geometries

A computationally efficient pseudospectral method is developed for incompressible flow simulations in two-dimensional geometries involving periodicity in one direction and significant surface deformations. A pseudoconformal mapping is used to map the flow domain into a rectangle, thereby establishing an orthogonal curvilinear coordinate system within which the governing equations are formulated. The time integration of the spectrally discretized, two-dimensional momentum equations is performed by a second-order mixed explicit/implicit time integration scheme. The satisfaction of the continuity equation is obtained through the solution of a Poisson equation for the pressure and the use of the influence matrix technique. A highly efficient iterative solver has been developed for the solution of a generalized Stokes problem at each time step based on a spectrally preconditioned biconjugate gradient algorithm, which exhibits almost linear scalability, requiring an orderNlog2Nnumber of operations, whereNis the number of unknowns. Numerical results are presented for two-dimensional steady, oscillatory, and peristaltic flows within an undulating channel, which agree well with previous results that have appeared in the literature.
Reverence for life.

Benedict Cosimi, MD, members, and guests of the New England Surgical Society, I am deeply appreciative for your willingness to honor me with the Nathan Smith Distinguished Service Award. Nathan Smith’s devotion to surgical education and teaching are the hallmarks of his career, which span from 1762 to 1829 (Figure 1). He was involved with the birth of surgery as a specialty in New England. During his long career, he was a major force in the development of Dartmouth Medical School, Hanover, NH. This was followed by an appointment in the new Yale School of Medicine, New Haven, Conn. He further contributed to the establishment of the medical schools at Bowdoin College, Brunswick, Me, and the University of Vermont, Burlington.
Probing Cochlear Resonators Using a New Microchamber

The mammalian cochlea is an acoustic spectrum analyzer and pressure transducer with a remarkable operating range, both in frequency and amplitude (Fettiplace & Hackney, 2006). A young, healthy human ear can capture sounds of 40 to 20,000 Hz in frequency and 20 μPa to 20 Pa (0 to 120 dB sound pressure level) in amplitude. One of the most significant achievements in decades regarding cochlear research is the identification of the cochlear amplifier. Tiny acoustic vibrations are amplified in the organ of Corti (OC)–sensori-eptithelium in the cochlea. Mechano-transducer receptors in the OC, called the outer hair cells, have been identified as the cellular actuators that provide energy to boost small pressure waves. However, the underlying mechanism of this amplification is still unclear.Copyright © 2013 by ASME
Congenital cleft lip and palate treatment plan

Abstract The prosthodontic treatment plan is one phase of a team effort that is comprehensive and long range in scope. An attempt is made to correlate all information related to the patient's problem in order to arrive at the best solution. Treatment is based on the premise that the burden of responsibility for therapy may shift to other disciplines at any time.
CD80 and PD-L2 define functionally distinct memory B cell subsets that are independent of antibody isotype

Memory B cells (MBCs) are long-lived sources of rapid, isotype-switched secondary antibody-forming cell (AFC) responses. Whether MBCs homogeneously retain the ability to self-renew and terminally differentiate or if these functions are compartmentalized into MBC subsets has remained unclear. It has been suggested that antibody isotype controls MBC differentiation upon restimulation. Here we demonstrate that subcategorizing MBCs on the basis of their expression of CD80 and PD-L2, independently of isotype, identified MBC subsets with distinct functions upon rechallenge. CD80(+)PD-L2(+) MBCs differentiated rapidly into AFCs but did not generate germinal centers (GCs); conversely, CD80(-)PD-L2(-) MBCs generated few early AFCs but robustly seeded GCs. The gene-expression patterns of the subsets supported both the identity and function of these distinct MBC types. Hence, the differentiation and regeneration of MBCs are compartmentalized.
Sustained viability and profileration of hemocytes from the cultured pharynx of Styela clava

In order to acquire more in-depth information on the site(s) of hemopoiesis in marine animals, we successfully cultured pharyngeal explants of the tunicate Styela clava over a period of 82 d. Transmission electron microscopy of resident hemocytes within explants revealed changes in hemocyte composition. Hemoblast-like cells increased shortly after commencement of the cultures (8.1% at Day 0 increasing to a maximum of 28.7% at Day 7). Autoradiography using 3H-thymidine incorporation confirmed that hemocyte proliferation in pharyngeal explants still continued after 37 d culture. During culture, the migration of many free cells into the medium resulted in sparse, residential hemocytes in the pharyngeal explants. Hemocyte migration increased by up to 4.3x105 cells/explant (max.) at 17 to 24 d, but finally decreased to 4.9x104 cells/explant at 75 to 82 d. Vital neutral-red staining revealed that many emerging cells were not hemocytes such as those found in the normal hemolymph. The continued development of in vitro approaches will strengthen analyses of immune-defense responses in tunicates which, as protochordates, are the immediate invertebrate ancestors of vertebrates.
Demystifying the black box: improving detection limits

One of six IDRC 17 Student award recipients, Ryan Lerud is in the PhD programme at Portland State University, being co-advised by Peter Moeck of the Physics Department and Shankar Rananavare of the Chemistry Department. Ryan has been using multivariate statistics to develop a NIR/Vis Portable Fruit Quality Meter as part of his Masters thesis and on-going internship with Felix Instruments, Camas, WA. In this article, Ryan discusses instrument design, the impact that design has on fluctuating temperature and voltage and the effect of the latter on model performance.
Characterization of Binary Patterns and Their Projections

Algorithms for reconstruction of a two-dimensional binary pattern Z from its row-projection vector A and column-projection vector B have been developed by Chang. The projection set (A,B) is said to be unique, nonunique, or inconsistent if it determines one binary pattern, more than one binary pattern, or no binary pattern. A binary patern Z is said to be ambiguous if there exists another pattern with the same projections, otherwise it is unambiguous. Two characterization questions of binary patterns and their projections are posed. First, given Z what is the necessary and sufficient condition for Z to be ambiguous, or unambiguous? Second, given (A,B), what is the necessary and sufficient condition for (A,B) to be unique, nonunique, or inconsistent? These two combinational questions are discussed and efficient algorithms to answer them are derived from some ideas of Ryser.
Integrated waste management via the Natural Laws

The basic tools of engineering, energy and material balances and rate expressions, provide a pathway to apply the Natural Laws of Hazardous Waste for proper waste management. Overall, one must focus on nature's limits, which are discussed, using open minded engineering practices for proper waste management. By expansion of balance concepts beyond ‘end-of-pipe’ and integrating concepts beyond basic life-cycles, as discussed in this paper, the true impact ofwaste management practices may be established. These cradle-to-grave balances are connected to nature's limits via results of recent work by others on risk assessment. The combination of approaches for evaluating concentration limits of chemicals in the environment allows the facility for an engineering solution for proper waste management. The method is presented by making example comparisons of choices of technology for recycling, storage, and site remediation.
Bureaucrats, Legislators, and the Size of Government

Some recent theories have blamed the growth of government on budget-maximizing bureaucrats who are assumedly capable of imposing their most preferred budget-output combination on legislatures, subject to cost and demand constraints. However, theoretical examination of the range of bargaining outcomes that might occur between bureau and legislature shows that budget-maximizing behavior does not necessarily lead to super-optimal levels of production, nor do the suggested reforms of competition and privatization necessarily improve the situation. In this bargaining model, the central determinants of governmental growth are not budget-maximizing bureaucrats, but the legislature's decisions regarding mode of oversight and form of internal organization.
A Design Exploration Method for Adaptive Design Systems

In this paper, we introduce a design exploration method for adaptive design systems (DEM-ADS), which is proposed to manage the uncertainty in the system design process. The proposed method includes the local regression model and an inverse design procedure derived from the existing Inductive Design Exploration Method (IDEM). To demonstrate the proposed method, the design of a photonic crystal coupler and waveguide containing two subsystem analyses is presented. The result indicates that the proposed method effectively attains solutions that are robust to uncertainty in the system more efficiently than IDEM.© 2009 ASME
The Importance of Three Membrane-distal Tyrosines in the Adaptor Protein NTAL/LAB

Abstract NTAL (non-T cell activation linker)/LAB (linker for activation of B cells) is a LAT (linker for activation of T cells)-like molecule that is expressed in B cells, mast cells, natural killer cells, and monocytes. Upon engagement of the B cell receptor or Fc receptors, it is phosphorylated and interacts with Grb2. LAB is capable of rescuing thymocyte development in LAT–/– mice. In this study, we utilized various LAB Tyr to Phe mutants to map the phosphorylation and Grb2-binding sites of LAB. We also examined the function of these mutants by investigating their ability to rescue signaling defects in LAT-deficient Jurkat cells and thymocyte development in LAT–/– mice. Our results indicated that human LAB was primarily phosphorylated on three membrane-distal tyrosines, Tyr136, Tyr193, and Tyr233. Mutation of these three tyrosines abolished Grb2 binding and LAB function. Our data suggested that these tyrosines are the most important tyrosines for LAB function.
Cavity flow past a slender pointed hydrofoil

A slender-body theory for the flow past a slender, pointed hydrofoil held at a small angle of Attack to the flow, with a cavity on the upper surface, has been worked out. The approximate solution valid near the body is seen to be the sum of two components. The first consists of a distribution of two-dimensional sources located along the centroid line of the cavity to represent the variation of the cross-sectional area of the cavity. The second component represents the crossflow perpendicular to the centroid line. It is found that over the cavity boundary which envelops a constant pressure region, the magnitude of the cross-flow velocity is not constant, but varies to a moderate extent. With this variation neglected only in the neighbourhood of the hydrofoil, the cross-flow is solved by adopting the Riabouchinsky model for the two-dimensional flow. The lift is then calculated by integrating the pressure along the chord; the dependence of the lift on cavitation number and angle of attack is shown for a specific case of the triangular plan form.
Physics of bandgap formation in Cu–Sb–Se based novel thermoelectrics: the role of Sb valency and Cu d levels

In this paper we discuss the results of ab initio electronic structure calculations for Cu3SbSe4 (Se4) and Cu3SbSe3 (Se3), two narrow bandgap semiconductors of thermoelectric interest. We find that Sb is trivalent in both the compounds, in contrast to a simple nominal valence (ionic) picture which suggests that Sb should be 5 + in Se4. The gap formation in Se4 is quite subtle, with hybridization between Sb 5s and the neighboring Se 4s, 4p orbitals, position of Cu d states, and non-local exchange interaction, each playing significant roles. Thermopower calculations show that Se4 is a better p-type system. Our theoretical results for Se4 agree very well with recent experimental results obtained by Skoug et al (2011 Sci. Adv. Mater. 3 602).
Commentary: Ambiguity in Narratives of Reconciliation: A Commentary on `Positioning in Accounting for Redemption and Reconciliation

Murakami's article on positioning in reconciliation narratives accurately portrays the way in which a former POW reformulates his identity and his past and reconciles with his time as a POW and the Japanese who held him. Through further analysis of the narrative provided, along with an additional narrative of reconciliation from the Rwandan Genocide, this commentary will reflect on the multiple positions that continually interact to create one's identity, the role of the collective culture in this process, and the ambiguity inherent in reconciliation.
Basic physics of MR contrast agents and maximization of image contrast

This review summarizes the physical basis of magnetic resonance (MR) imaging contrast agents, including both T1 agents, such as gadolinium-DTPA (diethylenetriaminepentaacetic acid), and T2 or T2* agents, such as superparamagnetic iron oxides. The maximization of image contrast and lesion visibility with contrast agents is described, and the use of contrast agents in MR angiography and perfusion imaging is discussed.
TOWARD A PSYCHO-TECHNICAL SYSTEMS PARADIGM OF ORGANIZATIONAL MEASUREMENT*

This paper proposes the need to revise the traditional paradigm of measurement as it applies to organizations. It develops the notion that measurement in an organizational context must be viewed as a “psycho-technical system,” a technology that is intended to influence behavior, including management decisions. It examines the functions of measurement as a psycho-technical system and presents proposed criteria consistent with this revised view of organizational measurement.
Angiotensin II and phorbol esters depress cardiac performance and decrease diastolic and systolic [Ca2+]i in isolated perfused rat hearts☆

Abstract Both angiotensin II and the protein kinase C activator, phorbol 12-myristate 13-acetate (PMA), significantly depressed developed pressure, oxygen consumption, and coronary flow in isolated perfused rat hearts and caused a decrease in diastolic and systolic [Ca 2+ ] i and [Ca 2+ ] i transients. PMA and angiotensin II did not change the levels of cAMP but moderately decreased PCrCr. The decrease in systolic [Ca 2+ ] i and amplitude of [Ca 2+ ] i transients caused by PMA and angiotensin II resulted in depressed cardiac function. Hearts perfused with PMA and angiotensin II had a decreased sensitivity to extracellular calcium. Depressed developed pressure and oxygen consumption in the PMA- and angiotensin II-treated hearts may have been due to a decrease in amplitude of effective [Ca 2+ ] i transients, because the [Ca 2+ ] i threshold for cross-bridge interaction was presumably higher than the diastolic [Ca 2+ ] i in these hearts.
Application of Parameter Optimization to the Optimum Burning Program for Horizontal Flight

A parameter optimization technique is applied to the optimization of the thrust history for missiles. The problem considered is that of determining the thrust history which maximizes the range of a continuously-variable thrust rocket in horizontal lifting flight. The optimal-control solution for this problem is developed. The optimal-control problem is then approximated by a parameter optimization problem which is solved using a quasi-Newton method with constraint projection. The two solutions compare well. This result allows confidence in the use of the parameter optimization technique to solve optimization problems in flight mechanics for which no analytical optimal-control solutions exist. The results demonstrate the need for a thorough understanding of the optimal control when designing the control parameterization scheme.
Symmetry and crystal structure of Ti3SiC2

Convergent beam electron diffraction (CBED) and X-ray diffractometry (XRD) have been used to examine the symmetry, structure and lattice parameters of Ti3SiC2. The CBED analysis confirms that the material is hexagonal with a point group of 6mmm. The XRD diffraction peak positions and intensities are in good agreement with calculations based on previously proposed atomic positions.
Computation of hypersonic flows with finite rate condensation and evaporation of water

A computer program for modelling 2D hypersonic flows of gases containing water vapor and liquid water droplets is presented. The effects of interphase mass, momentum and energy transfer are studied. Computations are compared with existing quasi-1D calculations on the nozzle of the NASA Langley Eight Foot High Temperature Tunnel, a hypersonic wind tunnel driven by combustion of natural gas in oxygen enriched air.
Studies on the Dissociation of Cryptomonad Biliproteins

The spectroscopic properties of two biliproteins, phycocyanin 645 and phycoerythrin 566, have been studied by treating the proteins with two different agents, NaSCN at pH 6.0, or pH 4.0 without NaSCN. For phycoerythrin 566, treatment with NaSCN revealed that the visible CD spectrum of its chromophores was separated into a pair of different spectra, and each of these spectra was observed as a negative and one or more positive bands. For phycocyanin 645, two negative CD bands have been observed previously, together with two or more positive bands, in the dimer (alpha 2 beta 2) state, and NaSCN treatment caused elimination of one of these negative bands. The dimer was stable at pH 6.0, but at pH 4.0 the spectra of phycocyanin 645 had one less negative band than those at pH 6.0. Chromatography demonstrated that phycocyanin 645 was a monomer (alpha beta) at pH 4.0. Monomers of cryptomonad biliproteins have never been observed before. Excitation at 514 nm, in picosecond time-resolved fluorescence studies, produced lifetimes of 11.0 and 45.2 ps for dimers and monomers, respectively. Excitation at 566 nm yielded times of 1.38 and 1.24 ps, for dimers and monomers, respectively. CD in the far UV showed that monomers and dimers had very similar secondary structures. These results have been used to test an hypothesis that proposed two types of exciton splitting among the chromophores of phycocyanin 645, and perhaps phycoerythrin 566 could also have this chromophore organization.
BpsR Modulates Bordetella Biofilm Formation by Negatively Regulating the Expression of the Bps Polysaccharide

Bordetella bacteria are Gram-negative respiratory pathogens of animals, birds, and humans. A hallmark feature of some Bordetella species is their ability to efficiently survive in the respiratory tract even after vaccination. Bordetella bronchiseptica and Bordetella pertussis form biofilms on abiotic surfaces and in the mouse respiratory tract. The Bps exopolysaccharide is one of the critical determinants for biofilm formation and the survival of Bordetella in the murine respiratory tract. In order to gain a better understanding of regulation of biofilm formation, we sought to study the mechanism by which Bps expression is controlled in Bordetella. Expression of bpsABCD (bpsA-D) is elevated in biofilms compared with levels in planktonically grown cells. We found that bpsA-D is expressed independently of BvgAS. Subsequently, we identified an open reading frame (ORF), BB1771 (designated here bpsR), that is located upstream of and in the opposite orientation to the bpsA-D locus. BpsR is homologous to the MarR family of transcriptional regulators. Measurement of bpsA and bpsD transcripts and the Bps polysaccharide levels from the wild-type and the ΔbpsR strains suggested that BpsR functions as a repressor. Consistent with enhanced production of Bps, the bpsR mutant displayed considerably more structured biofilms. We mapped the bpsA-D promoter region and showed that purified BpsR protein specifically bound to the bpsA-D promoter. Our results provide mechanistic insights into the regulatory strategy employed by Bordetella for control of the production of the Bps polysaccharide and biofilm formation.
Effect of pH on the Water/α-Al2O3 (11̅02) Interface Structure Studied by Sum-Frequency Vibrational Spectroscopy

Effect of pH on the Water/-Al 2 O 3 ( 1102 ) interface structure studied by Sum-Frequency Vibrational Spectroscopy Jaeho Sung,† Luning Zhang,† Chuanshan Tian,† Y. Ron Shen,† and Glenn A. Waychunas*,‡ †Department of Physics, University of California, Berkeley, California 94720, and ‡Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 Email: GAWaychunas@lbl.gov Abstract Sum frequency vibrational spectroscopy (SFVS) was used to study the structure of water/- Al 2 O 3 ( 1102 ) interfaces at different pH values. The OH stretch spectra are dominated by interfacial water contributions at lower frequencies, and by bonded hydroxyls on the Al 2 O 3 surface at higher frequencies. Protonation and deprotonation of various oxide functional groups at the -Al 2 O 3 surface as pH varies can be monitored quantitatively by changes of the spectrum, allowing their pK reaction values can be estimated. The point of zero charge of the interface is found to be at pH ~ 6.7. Introduction Metal oxide surfaces in contact with water are terminated by functional groups (oxygens connected to one or more metal ions) that can create local positive or negative charges due to protonation or deprotonation, respectively. Since chemical reactions at oxide/water interfaces, especially those in geochemistry, heterogeneous catalysis, semiconductor processing, electrochemistry, corrosion, and atmospheric chemistry, are very sensitive to both net surface charge and the arrangement of surface charged species, 1-5 it is crucial to understand protonation/deprotonation processes and the accompanying hydrogen bonding geometry at the molecular level. Much previous work on metal oxide surfaces has been done using
Improvement of the Delany-Bazley and Miki models for fibrous sound-absorbing materials

A new model for predicting the acoustical properties of fibrous materials, the characteristic impedance Zc and the propagation constant γ, only from their airflow resistivity was constructed. The Delany-Bazley and Miki models are well known as conventional prediction methods. Their formulas are similar, and their difference is in the values of coefficients and degrees in the formulas. In this research, the acoustical properties and airflow resistivity of fibrous materials, 15 types of glass wool and 9 types of rock wool, were measured and compared with values obtained by conventional methods of prediction. It was found that the introduction of an expression involving the common logarithm improved the conventional models. This new model is more effective than the conventional models, particularly for the prediction for high-density fibrous materials where f⁄σ 0.1 m3/kg.
Differential sensitivity to hibernation of early and late events in development of the immune response

Ground squirrels, Citellus tridecemlineatus, were immunized with a single intraperitoneal injection of sheep red cells four days before, two days before, during and upon arousal from hibernation. The number of antibody-forming cells per spleen was determined at different times during 56 days of hibernation and during the first week following arousal. All phases of the response, i.e., latent period, proliferative phase, declining phase, were slowed during the hibernation period and we concluded that most of the development occurred during the short periods of spontaneous arousal. The latent period, as compared to the other phases, was the most sensitive to retardation by hibernation. We believe that the resumption of development of the immune response during this phase is relatively delayed upon arousal because the early differentiating cells entered a quiescent state better adapted to hibernation whereas the later cell types did not.
Fluorapatite and fluorite solubility controls on geothermal waters in Yellowstone National Park

Abstract Potential solubility controls on phosphorus in Yellowstone National Park geothermal waters were investigated using the analytical phosphate estimates of Stauffer and Thompson (1978), the computer program, WATEQF, and adopting the equilibrium constant: log K 25° = −61.4 for fluorapatite (FAP = Ca5(PO4)3F) dissolution. The near-boiling high-Cl geyser and spring effluents are at or near saturation with respect to (with) FAP. The sixteen representative springs in this category had FAP saturation indices ( S.I. = log IAP/K r ) ranging from − 3.2 to +4.9 and averaging +0.9. The strongly positive indices were all associated with the highly alkaline conditions resulting from adiabatic cooling in the near surface environment. Hot spring waters indicating extensive dilution (reduced Cl) by meteoric water have lower pH's, and despite PO4 and Ca concentrations an order of magnitude higher than the geysers, are still frequently undersaturated with FAP. The travertine-depositing “Mixed-water” springs are invariably supersaturated with FAP at ground surface and at or near saturation with hydroxylapatite. Supersaturation may result from kinetic inhibition of apatite crystallization by the elevated Mg2+, HCO3−, and lower temperatures in these springs. The phosphates may be residuals of the meteoric dilution water. Separately, if Strubel's temperature-dependent estimates of fluorite (CaF2) solubility are adopted, the high-Cl geysers and springs on “Geyser Hill” and at Norris are consistently undersaturated with CaF2 at the 90–100° orifice temperatures. The apparent disequilibrium may reflect fluorite equilibration at the much higher temperatures (> 200°C) in the deeper enthalpy reservoirs.
FTIR Vibrational Circular Dichroism Of Oligopeptides Related To Polyproline

Vibrational Circular Dichroism (VCD) data can be routinely measured by FTIR. On our FTIR VCD instrument it is possible to obtain a spectrum where baseline correction is accomplished with solvent only. Such capability is important for measuring biological systems. Several polypeptides that have been assigned to be in 'random coil' conformation all give an amide I VCD pattern which has the same sign and bandshape as poly-L-proline II but a smaller magnitude. This is consistent with a previous proposal by Tiffany & Krimm that the 'random coil' conformation of charged polypeptides actually has a significant local ordering in the form of a left-handed extended helix. To investigate this problem further we have studied the effects of temperature and chain length on the VCD bandshape of this conformational type. The latter studies were done with (Pro)n, n=2-7. Our results indicate that even at the level of (Pro)4 the VCD spectrum has the same bandshape, sign and intensity as found in the 'random coil' poly-L-glutamic acid spectrum. Data on various 'random coil' systems will be compared to the model studies we have done.
Biomechanical effects of flow and coculture on human aortic and cord blood-derived endothelial cells.

Human endothelial cells derived from umbilical cord blood (hCB-ECs) represent a promising cell source for endothelialization of tissue engineered blood vessels. hCB-ECs cultured directly above human aortic smooth muscle cells (SMCs), which models native and tissue engineered blood vessels, produce a confluent endothelium that responds to flow like normal human aortic endothelial cells (HAECs). The objective of this study was to quantify the elastic modulus of hCB-ECs cocultured with SMCs under static and flow conditions using atomic force microscopy (AFM). Cytoskeleton structures were assessed by AFM cell surface imaging and immunofluorescence of F-actin. The elastic moduli of hCB-ECs and HAECs were similar and significantly smaller than the value for SMCs in monoculture under static conditions (p<0.05). In coculture, hCB-ECs and HAECs became significantly stiffer with moduli 160 – 180% larger than their corresponding values in monoculture. While the moduli of hCB-ECs and HAECs almost doubled in monoculture and flow condition, their corresponding values in coculture declined after exposure to flow. Both the number and diameter of cortical stress fiber per cell width increased in coculture and/or flow conditions, whereas the subcortical stress fiber density throughout the cell interior increased by a smaller amount. These findings indicate that changes to biomechanical properties in coculture and/or exposure to flow are correlated with changes in the cortical stress fiber density. For ECs, fluid shear stress appeared to have greater effect on the elastic modulus than the presence of SMCs and changes to the elastic modulus in coculture may be due to EC-SMC communication.
Spatial prediction of invasion success across heterogeneous landscapes using an individual-based model

The limited resources available for managing invasive plant species in native ecosystems and the magnitude of the problem make it essential that we develop methods to prioritize sites for management efforts. We used the individual-based simulation model ECOTONE in conjunction with climate and soil texture data to identify grassland site types where the invasive perennial forb Acroptilon repens is likely to be successful, and to create a threat map indicating the most vulnerable regions of Colorado. Acroptilon repens has the potential to become most abundant in dry areas with fine-textured soils. This information can be used to direct management efforts towards the areas at greatest risk, allowing the most effective use of limited resources. The most common approach for identifying invasible regions has been to extrapolate from the locations of existing invasions to find similar sites. Two major drawbacks to this method are the lack of consideration of the role of the existing plant community in inhibiting or facilitating invasion, and the assumption that the invading species is at equilibrium with the environment. The combination of an individual-based simulation model and a geographic information system provides a flexible tool to investigate the community and regional dynamics of invasive plant species.
Importance of the Lu-Hf isotopic system in studies of planetary chronology and chemical evolution

The Lu-176-Hf-176 isotope method and its applications in earth sciences are discussed with regard to planetary-evolution studies. From new data on basalts from oceanic islands, Hf-176/Hf-177 and Nd-143/Nd-144 are found to display a single linear isotopic variation in the suboceanic mantle, whereas considerable divergences occur in Hf-176/Hf-177-Sr-87/Sr-86 and Nd-143/Nd-144-Sr87/Sr-86 diagrams. With the acquisition of further Hf-Sr-Nd isotopic data, these discordant Sr-87/Sr-86 relationships may allow a distinction between processes such as mantle metasomatism, influence of sea-water altered material in the magma source, or recycling of sediments into the mantle. The best quality Hf isotope data are obtained from granitoid or zircons, and are most suitable for studying ancient terrestrial Hf isotopic variations. Lu-Hf is shown to be a viable method for dating ancient terrestrial and extraterrestrial samples, but is unlikely to find wide application in pure chronological studies because it offers little advantage over existing methods.
Assessment of the potential impact of the mysid shrimp, Neomysis mercedis, on Daphnia

Neomysis mercedis, an important invertebrate predator in some lakes and estuaries in North America, occurred at high densities (>2 mysids m -3 ) in Lake Washington in the early 1960s, a period when Daphnia were scarce in the lake. Because Neomysis feed selectively on Daphnia, it was hypothesized that mysid predation contributed significantly to the scarcity of Daphnia. To evaluate this hypothesis, mysid abundance was monitored in the lake (July 1989-February 1992), and whole lake predation impacts on Daphnia were estimated. Mysid abundance varied from 319 million, ∼0.1 mysids m -3 (February 1992) to 4276 million, ∼1.7 mysids m -3 (June 1991), and mysid biomass ranged from 1153 (October 1991) to 4700 kg dry weight (November 1990). A peak in Daphnia consumption was noted during autumn, when total mysid biomass was high. In late autumn/winter mysid consumption month -1 accounted for 28-95% of Daphnia biomass and 13-38% of production. Mysid densities in this study were 18x and 5x lower than in 1962 and 1975, respectively. By extrapolation, at a density of 3.5 mysids m -3 observed in the early 1960s, total Neomysis consumption demand month -1 exceeded 100% of Daphnia biomass (late autumn-early spring), and 100% of Daphnia production (late autumn-winter). Estimates of the total mysid consumption demand in this study are thus in accord with the hypothesis that Neomysis could control Daphnia abundance in Lake Washington.
Diffusion in polymers below the glass transition temperature: Comparison of two approaches based on free volume concepts

Theories based on free-volume concepts have been developed to characterize the self and mutual diffusion coefficients of low molecular weight penetrants in rubbery and glassy polymer-solvent systems. These theories are applicable over a wide range of temperatures and concentrations. In this paper, two alternative freevolume based approaches used to evaluate the solvent self-diffusion in glassy polymer-solvent systems are compared in terms of their differences and applicability
Right lower quadrant pain in children caused by omental infarction

Abstract Background: Omental infarction is a rare cause of abdominal pain, with fewer than 300 cases reported in the literature. Only 15% of reported cases occur in the pediatric population. We present our experience with 18 children diagnosed with omental infarction admitted to Texas Children’s Hospital over a 15-year period. Study design: A retrospective review of clinical records, diagnostic images, and pathologic findings was carried out for all children diagnosed with isolated omental infarction from 1986 to 2000 in order to analyze presenting signs and symptoms, preoperative imaging, surgical management, and postoperative outcomes. Results: Eighteen children were treated for isolated omental infarction. There were 12 boys and 6 girls with an average age of 7.5 years (range 2 to 13). All patients presented with acute onset of right lower quadrant pain. Only 5 of 18 (24%) had associated gastrointestinal symptoms. The average temperature at presentation was 99.4°F (± 0.78). The average white blood cell count was 11.4 (± 4.4). Fourteen patients had ultrasonographys performed preoperatively: 6 of 14 incorrectly diagnosed appendicitis, 4 of 14 were nondiagnostic and 4 of 14 correctly diagnosed omental infarction. Two of 18 patients underwent computed tomography scans, which were diagnostic for omental infarction. Resection of the infarcted omentum was performed in all patients and appendectomy in 16 of 18. Thirteen patients underwent an open procedure, 5 were performed laparoscopically. There were no postoperative complications. All patients had resolution of pain postoperatively and were discharged an average of 3.0 (± 0.9) days after admission. Conclusions: Omental infarction is an uncommon cause of right lower quadrant pain in children and is often diagnosed as appendicitis preoperatively. Ultrasonography and computed tomography can be diagnostic. Surgical resection of the infarcted omentum results in immediate resolution of pain with no morbidity.
BitSNAP: dynamic significance compression for a low-energy sensor network asynchronous processor

We present a novel asynchronous processor architecture called BitSNAP that utilizes bit-serial datapaths with dynamic significance compression to yield extremely low-energy consumption. Based on the sensor network asynchronous processor (SNAP) ISA, BitSNAP can reduce datapath energy consumption by 50% over a comparable parallel-word processor, while still providing performance suited for powering low-energy sensor network nodes. In 180 nm CMOS, the processor is expected to run at between 6 and 54 MIPS while consuming 152 pJ/ins at 1.8 V and just 17 pJ/ins at 0.6 V.
General solutions for stress-induced polarization in optical fibers

General solutions of thermal stresses and material birefringence in polarization-maintaining optical fibers are presented. The solutions give the stresses and birefringence at every point in the cross section of various fibers. The fundamental solution of the stress field is constructed by using the complex variable method in elasticity. When the cores, inner claddings, or stress-inducing regions are ellipses, circles, or bow-tie shapes, exact closed-form solutions can be found. The average core birefringence and center core birefringence of elliptical core, elliptical cladding, twin core, Panda, and bow-tie fibers are calculated and compared. Among these fibers, the bow-tie fiber shows the highest birefringence. >
Computer Classification of Reservoir Sandstones

A procedure is developed to extract numerical features which characterize the pore structure of reservoir rocks. The procedure is based on a set of descriptors which give a statistical description of porous media. These features are evaluated from digitized photomicrographs of reservoir rocks and they characterize the rock grain structure in term of (1) the linear dependency of grey tones in the photomicrograph image, (2) the degree of "homogeneity" of the image and (3) the angular variations of the image grey tone dependencies. On the basis of these textural features, a simple identification rule using piecewise linear discriminant functions is developed for categorizing the photomicrograph images. The procedure was applied to a set of 243 distinct images comprising 6 distinct rock categories. The coefficients of the discriminant functions were obtained using 143 training samples. The remaining (100) samples were then processed, each sample being assigned to one of 6 possible sandstone categories. Eighty-nine per cent of the test samples were correctly identified.
Perl Programming for Biologists. D. Curtis Jamison. Hoboken, NJ: Wiley-Liss, A John Wiley Sons Publication, 2003, 202 pp., $42.95, softcover. ISBN 0471-43059-5.

The biologist of today is a different species from his or her predecessors of only a few years ago. Even the most classic branch of biological sciences, taxonomy, is now a domain of elaborate computer searches and comparisons of genomic and phylogeny information. Computers have become indispensable tools in all branches of biology, and computer programming is an essential skill for today’s biologist. However, even a few years ago most biology graduates were not required to take computer classes. To stay on the cutting edge of science, they have to make up for this. Perl Programming for Biologists is a good attempt to create a skillful programmer from a person with a very limited computer background. The book starts with a useful introduction that clearly explains why one cannot avoid computing in biology and why perl is well suited in the context of bioinformatics. The book consists of three parts and an appendix. The first four chapters make up “The Basics” part. In the short first chapter, “Introduction to perl”, the author presents an example of the traditional Hello World script. This is a good introduction, although with a caveat—the hello.pl program may not run because the current user directory is rarely included in the UNIX PATH. A short additional sentence, …
Skin-, nipple-, and areola-sparing mastectomy

Surgical management of breast carcinoma has evolved to include more breast conserving techniques such as skin-, nipple-, and areola-sparing mastectomies, as improved cosmesis becomes an increasing concern. However, the oncologic risk of these procedures must be strongly considered before such techniques can be widely adopted. Here we review available literature on these techniques and their associated clinical outcome. From our own experience, as well as from that reported, we conclude that nipple-, skin-, and areola-sparing mastectomies in carefully selected patients can have safe oncologic outcomes comparable to more traditional surgical techniques and therefore may be a feasible option for breast cancer management.
Temperature-dependent sex determination modulates cardiovascular maturation in embryonic snapping turtles, Chelydra serpentina

We investigated sex differences in cardiovascular maturation in embryos of the snapping turtle Chelydra serpentina, a species with temperature-dependent sex determination. One group of eggs was incubated at 26.5°C to produce males. Another group of eggs was incubated at 26.5°C until embryos reached stage 17; eggs were then shifted to 31°C for 6 days to produce females, and returned to 26.5°C for the rest of embryogenesis. Thus, males and females were at the same temperature when autonomic tone was determined and for most of development. Cholinergic blockade increased resting blood pressure (P(m)) and heart rate (f(H)) in both sexes at 75% and 90% of incubation. However, the magnitude of the f(H) response was enhanced in males compared with females at 90% of incubation. β-adrenergic blockade increased P(m) at 75% of incubation in both sexes but had no effect at 90% of incubation. β-adrenergic blockade reduced f(H) at both time points but produced a stronger response at 90% versus 75% of incubation. We found that α-adrenergic blockade decreased P(m) in both sexes at 75% and 90% of incubation and decreased f(H) at 75% of incubation in both sexes. At 90% of incubation, f(H) decreased in females but not males. Although these data clearly demonstrate sexual dimorphism in the autonomic regulation of cardiovascular physiology in embryos, further studies are needed to test whether differences are caused by endocrine signals from gonads or by a hormone-independent temperature effect.
Case Report: Vertebral Osteomyelitis/Discitis as a Complication of Capnocytophaga canimorsus Bacteremia

A 31-year-old man with a history of congenital ventricular septal defect presented to the Emergency Department with 3 days of fever and palpitations. Four days earlier he sustained a dog bite to the left hand with localized swelling that rapidly resolved without additional signs of infection. No other source of fever was identified on history and physical examination. He was admitted to the hospital for evaluation of the origin of the fever, including possible endocarditis. Complete cardiac evaluation revealed no valvular infection. On the fifth hospital day, the patient developed severe lower back pain. Magnetic resonance imaging of the lumbar spine revealed L4-5 vertebral osteomyelitis and discitis. Blood cultures were positive for Capnocytophaga canimorsus. Antibiotics were continued and recovery was complete and uneventful.
Attachment, ego–identity development and exploratory interest in university students

We investigated the relationships between attachment security, ego-identity development and exploratory interest in 161 university students who completed categorical and dimensional scales of attachment style, an ego-identity development scale based on Erikson’s theory, and an exploratory interest scale. Factor analysis yielded three interpretable dimensions of exploratory interest: intellect, escape and activity. High ego development was associated with attachment security. Exploratory interest was weakly associated with attachment security, but more strongly associated with high ego-identity development. Further analyses revealed that ego-identity development predicts escape only for those with a negative model of self (i.e. preoccupied and fearful attachment styles), and ego-identity development predicts activity only for those with a positive model of self (i.e. secure and dismissing attachment styles).