cssi/SciSciGPT-SciSciNet huggingface dataset:
Technical efficiency of Critical Access Hospitals: an application of the two-stage approach with double bootstrap

The Critical Access Hospital (CAH) Program has offered Medicare cost-based reimbursement to small hospitals that meet certain eligibility criteria to improve their financial viability and quality of care. However, cost-based reimbursement has been associated with inefficiency in hospital operations. This study uses a two-stage approach and bootstrap procedures to examine the effects of environmental variables on the technical efficiency of CAHs. The two-stage approach with quality controls significantly improved statistical efficiency of parameter estimates in the second stage bootstrapped truncated regression relative to a similar model without quality controls. Overall, our results suggest that enhanced Medicare reimbursement may not have had detrimental effects on the technical efficiency of CAHs.
Efficient use of variation in evolutionary optimization

Evolutionary algorithms face a fundamental trade-off between exploration and exploitation. Rapid performance improvement tends to be accompanied by a rapid loss of diversity from the population of potential solutions, causing premature convergence on local rather than global optima. However, the rate at which diversity is lost from a population is not simply a function of the strength of selection but also its efficiency, or rate of performance improvement relative to loss of variation. Selection efficiency can be quantified as the linear correlation between objective performance and reproduction. Commonly used selection algorithms contain several sources of inefficiency, some of which are easily avoided and others of which are not. Selection algorithms based on continuously varying generation time instead of discretely varying number of offspring can approach the theoretical limit on the efficient use of population diversity.
Ancient evolution of stress-regulating peptides in vertebrates.

Abstract Recent studies on genomic sequences have led to the discovery of novel corticotropin-releasing factor (CRF) type 2 receptor-selective agonists, stresscopin (SCP)/urocortin III (UcnIII), and stresscopin-related peptide (SRP)/urocortin II (UcnII). In addition, analyses of vertebrate genomes showed that the CRF peptide family includes four distinct genes, CRF, urocortin/urotensin I, SCP/UcnIII, and SRP/UcnII. Each of these four genes is highly conserved during evolution and the identity between mammalian and teleost orthologs ranges from >96% for CRF to >55% for SCP. Phylogenetic studies showed that the origin of each of these peptides predates the evolution of tetrapods and teleosts, and that this family of peptide hormones evolved from an ancestor gene that developed the CRF/urocortin and SCP/SRP branches through an early gene duplication event. These two ancestral branches then gave rise to additional paralogs through a second round of gene duplication. Consequently, each of these peptides participates in the regulation of stress responses over the 550 million years of vertebrate evolution. The study also suggested that the fight-or-flight and stress-coping responses mediated mainly by CRF types 1 and 2 receptors evolved early in chordate evolution. In addition, we hypothesize that the CRF/CRF receptor signaling evolved from the same ancestors that also gave rise to the diuretic hormone/diuretic hormone receptors in insects. Thus, a complete inventory of CRF family ligands and their receptors in the genomes of different organisms provides an opportunity to reveal an integrated view of the physiology and pathophysiology of the CRF/SCP family peptides, and offers new insights into the evolution of stress regulation in vertebrates.
Existence and shapes of menisci in detached Bridgman growth

Abstract In detached Bridgman growth, the crystal radius is less than the crucible radius and a meniscus bridges the gap between the crystal and crucible wall. Existence of detached growth depends upon the contact angle of the melt with the crucible wall, the growth angle of the solidifying crystal, the pressure differential across the meniscus, and the Bond number. The Young–Laplace capillary equation is used to calculate the crystal radii of detached states as a function of the pressure differential across the meniscus. Both terrestrial and microgravity conditions are considered. A variety of solution states is found, and multiple solutions with different crystal radii can exist for a given value of the pressure differential. The meniscus shapes for the detached states vary from simply convex or concave to shapes with numerous inflections. An approximate solution to the Young–Laplace equation for small Bond numbers is derived.
The role of Vldlr in intraretinal angiogenesis in mice.

Retinal vasculature is essential for normal visual function of the eye. Vascular abnormalities, including ischemia, neovascularization, and vessel leakage occur in common eye diseases such as diabetic retinopathy, age-related macular degeneration (AMD), and macular edema, which are some of the leading causes of blindness in adults.1–3 Retinal angiomatous proliferation (RAP), characterized by subretinal neovascularization originating from retinal vessels, is a subtype of AMD and accounts for 10% to 15% of neovascular AMD.4–8 Recent studies have reported that very-low-density lipoprotein receptor (Vldlr) knockout mice replicate some characteristic phenotypes of human RAP, suggesting that Vldlr mutant mice can be used as animal models for studying the underlying mechanism of the development of RAP.9–13 Vldlr knockout (−/−) mice develop retinal angiomatous proliferation with subretinal neovascularization arising from retinal vessels.10–13 In Vldlr−/− mice, retinal vessels grow into the subretinal space, which results in retinal–choroidal anastomosis, subretinal fibrosis, retinal pigment epithelium (RPE) hyperplasia, and photoreceptor degeneration. The loss of Vldlr facilitates the proliferation, migration, and capillary-like formation of retinal vascular endothelial cells and enhances the angiogenic properties of endothelial cells in vitro and in vivo.14 Thus, Vldlr negatively regulates retinal angiogenesis during development. Moreover, recent findings have indicated Vldlr as one of the functional candidate genes in human AMD.15 However, the underlying mechanism for how the Vldlr mutation promotes retinal angiogenesis remains unclear; it is also unclear whether this retinal phenotype is associated with the function of Vldlr as a receptor for the uptake of very-low-density lipoprotein (VLDL) or as a mediator for other intracellular signaling. We report the identification and characterization of a new recessive Vldlr mutation, r26, from N-ethyl-N-nitrosourea (ENU)-mutagenized mice. The r26 mutant mice contain a missense point mutation of the Vldlr gene, leading to the expression of a truncated Vldlr protein with a premature termination at amino acid residue 747. Similar to the Vldlr−/− mice, the r26 homozygous mice display uncontrolled intraretinal angiogenesis. This work further demonstrates the essential role of the C terminus of Vldlr in the regulation of intraretinal angiogenesis. This truncated Vldlr mouse line is a useful model for the study of the underlying mechanism for Vldlr signaling and human RAP.
Attachment Models and Memory for Conversation

Attachment models were hypothesized to influence interest in an unfamiliar peer's conversational ideas by supplying default expectations for rewards that others provide. Having positive models of others would enhance attention to and memory for the peer's remarks. Undergraduates rated themselves on secure, dismissing, preoccupied, and fearful attachment styles and several weeks later acted as participants or observers in short or long conversations with scripted confederates. Immediately after the conversations, they took recall tests about the confederate's remarks. Recall of the confederate's ideas was positively correlated with measures of positive models for others, which were computed from the attachment style ratings, but the correlation was qualified in regression analyses by interactions between the attachment measures and conversation role, length, and sex composition of the student-confederate dyad. Results are discussed in terms of attachment-related motives and experience in same-sex and oppos...
Reduction of error effects in digital partitioning by error-correction coding

Analog optical matrix-vector multipliers (OMVMs) compute matrix-vector products rapidly due to the parallelism and high speed of optics. However, their low analog accuracy hinders their widespread application. Digital partitioning is a promising new technique for achieving high accuracy computations on analog OMVMs. One potential drawback of digital partitioning is its sensitivity to errors. The results presented here show how error-correcting codes can reduce this sensitivity to errors. Various computer simulation results are presented to show that a significant reduction of error can be obtained.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Testmeal Responses Following m-Chlorophenylpiperazine and L-Tryptophan in Bulimics and Controls

Testmeal Responses Following m-Chlorophenylpiperazine and L-Tryptophan in Bulimics and Controls
The bonding properties of elastomer tray adhesives

1. The surface yielded by the acrylic resin formed against tinfoil provided better retention for the rubber base than any other surface tested. 2. Wax consistently gave the worst results in spite of careful boiling out. 3. The use of wax or asbestos spacers would not degrade the resin surface if tinfoil, or presumably the more easily obtainable aluminum foil, were used as a separating medium. 4. For drying times of between 15 minutes and 72 hours, no significant change was found in bond strength of elastomer to tray material. 5. Drying times of less than 15 minutes were found to be inadequate and to decrease bond strength; they are clinically inadvisable. 6. If, as a result of unavoidable delay, a tray is painted and then left for a number of days prior to making the impression, satisfactory bonding will still occur. However, if the dentist wishes to apply a second coat and dry it for 15 minutes, an increase in bond strength is likely to occur. 7. In the six systems tested, failure occurred at varied levels, from a low of 20 p.s.i. to a high of 80 p.s.i. 8. In the silicone and polyether systems, cohesive failure of the elastomer occurred before the adhesive bond between elastomer and tray failed. This finding correlates with the clinical observation that silicones and polyethers are more difficult to remove completely from acrylic resin trays when an impression has to be repeated.
Regional Monte Carlo solution of elliptic partial differential equations

Abstract A continuous random walk procedure for solving some elliptic partial differential equations at at a single point is generalized to estimate the solution everywhere. The Monte Carlo method described here is exact (except at the boundary) in the sense that the only error is the statistical sampling error that tends to zero as the sample size increases. A method to estimate the error introduced at the boundary is provided so that the boundary error can always be made less than the statistical error.
Accuracy and fidelity of fast net length estimates

Most popular tools for VLSI placement rely on some type of local search algorithm to iteratively refine a given placement solution. In such algorithms, it is necessary to evaluate the total amount of routing that a given placement will require. Typially, rectilinear Steiner tree heuristics are used to estimate the routing length of a placement. When evaluating heuristics, researchers typically focus on their ```absolute`` accuracy, i.e., how nearly optimal are their solutions? However, here a more pertinent statistic is their ```relative accuracy``, i.e. how likely is it that a given heuristic will agree with the optimum on which of two instances has the shorter routing? In this paper, we experimentally evaluate four popular net length estimation heuristics, with respect to both their absolute and relative accuracy as well as their speed.
Oceanic ambient noise as a background to acoustic neutrino detection

Ambient noise measured in the deep ocean is studied in the context of a search for signals from ultrahigh-energy cosmic ray neutrinos. The spectral shape of the noise at the relevant high frequencies is found to be very stable for an extensive data set collected over several months from 49 hydrophones mounted near the bottom of the ocean at $\ensuremath{\sim}1600\text{ }\text{ }\mathrm{m}$ depth. The slopes of the ambient noise spectra above 15 kHz are found to roll off faster than the $\ensuremath{-}6\text{ }\text{ }\mathrm{dB}/\mathrm{\text{octave}}$ seen in Knudsen spectra. A model attributing the source to a uniform distribution of surface noise that includes frequency-dependent absorption at large depth is found to fit the data well up to 25 kHz. This depth-dependent model should therefore be used in analysis methods of acoustic neutrino pulse detection that require the expected noise spectra.
Interpretations of immune responses of mice to poly(Glu60Lys40), its modified derivatives, and the terpolymers poly(Glu55Lys37Leu8) and poly(Glu56Lys37Ser7)

Abstract Reinvestigations of the murine immune responses against poly(Glu 60 Lys 40 ) and its derivatives modified with covalently linked amino acids indicated that they all could be immunogenic at high concentrations in all inbred strains. In contrast restricted responsiveness was noted with terpolymers as follows: to poly(Glu 55 Lys 37 Leu 8 ) mice of H-2 a,d,k haplotypes, to poly(Glu 56 Lys 37 Ser 7 ) mice of H-2 a,k haplotypes. It is hypothesized that the increased hydrophobicity of the modified GL derivatives can lead to increased combining constants with the antigen-specific T-cell receptor (V H -Ia complexes?) which may be responsible for the enhanced immunogenicity and positive in vitro T-cell proliferative responses detected with the modified GL(T) 4.7 . A similar hypothesis involving increased reactions with V H idiotypes on T cells is advanced to account for some of the known unique strain distribution patterns of the glu lys terpolymers containing limited amounts of a third α-amino acid.
Estimating the atmospheric input of pollutants into a watershed

Estimating the atmospheric input of ions to a watershed has traditionally been accomplished through either the extrapolation of point measurements of deposition or the integration of model estimated deposition. This paper examines the characteristics of precipitation chemistry on the eastern seaboard of the United States where precipitation quality could conceivably affect fish habitats in estuaries. The measured values presented here have been extracted from the data base of the Utility Acid Precipitation Sampling Program (UAPSP) precipitation chemistry network. These data illustrate the nature of ionic deposition at four points on the eastern seabord. The deposition of H' (acidity) is shown to be dependent upon the amount of sulfate and, to a lesser degree, nitrate in the precipitation. It is also shown that the quantity of ionic deposition on a storm-by-storm basis was influenced by the amount of water deposition but the relationship was not very strong. Thus the use of water deposition as a surrogate for ionic deposition is not justified in these watersheds. Finally, it is shown that the deposition of H+, SO42−, NO3−, and NH4+ were not clearly seasonal. While a large percentage of total ionic deposition occurred in a small number of precipitation events, these exceptional events were not confined to a particular season.
Tremorgenic indole alkaloid studies. 6. Preparation of an advanced intermediate for the synthesis of penitrem D. Synthesis of an indole oxocane

Abstract We describe here an efficient synthesis of tricyclic aniline 9 , an advanced synthetic intermediate which embodies the B-C-D rings of the penitrems (A–F), a small family of tremorgenic mycotoxins produced by the ergot fungus Penicillium crustosum. In addition, we demonstrate the feasibility of a general synthetic tactic for the sequential generation of the E , F , and A rings by construction of a diminutive version of the natural products, specifically indole-oxocane 23 . Central to our approach to aniline 9 was a photochemical [2+2]-cycloadditon of methyl acrylate to enone 16 , followed successively by a Robinson annulation and Semmler-Wolff aromatization. Assembly of 23 entailed a moditied Madelung indole synthesis combined with a novel acid-promoted bis-cyclization ( 47 → 46 ) to install the oxocane ring system.
Ultrasound-Guidance Can Reduce Adverse Events During Femoral Central Venous Cannulation

Abstract Background Ultrasound-guidance for internal jugular central venous cannulation (CVC) has become the recommended best practice and has been shown to improve placement success and reduce complications. There is a dearth of studies that evaluate emergency point-of-care ultrasound guidance of femoral CVC. Objective Our aim was to determine if point-of-care ultrasound guidance for femoral CVC decreases adverse events and increases the likelihood of successful placement when compared with the landmark technique. Methods We conducted an Institutional Review Board–approved, prospective, observational study of consecutive patients who required CVC. Physicians who performed CVC completed a standardized, web-based data sheet for a national CVC registry. We evaluated single-institution data regarding CVC site, ultrasound usage, CVC indication, and mechanical complications (e.g., pneumothorax, arterial puncture, failed access, catheter misdirection, and hematoma). The study period was between January 2006 and June 2010. Analysis using Pearson's χ 2 and Agresti-Coull binomial confidence intervals was performed; significance was defined as p Results We evaluated data for 143 patients who had femoral CVC in our institution. Sixty CVCs (42%) were performed under ultrasound guidance, 83 (58%) via landmark technique ( p = 0.0159); 3.3% of femoral central venous lines placed by ultrasound guidance had recorded adverse events compared with 9.6% for the landmark technique ( p = 0.145). There was no statistically significant difference in complications between ultrasound-guidance and landmark techniques. Our data showed a trend toward decreased rates of arterial puncture and reduced cannulation attempts resulting in improved placement success. Conclusions Our experience shows that ultrasound guidance for femoral CVC might decrease complications and improve placement success, although we cannot recommend this approach without additional data. We recommend a larger study to further evaluate this technique.
A genetic method for defining DNA-binding domains: application to the nuclear receptor NGFI-B

A method is described that allows for rapid and efficient generation of functional mutations in DNA-binding domains of proteins. The target DNA-binding domain is attached to the Gal4p transcriptional-activating domain and expressed in yeast. The binding site recognized by the target domain is placed upstream of a gene that produces a protein toxic to yeast cells, so that the chimeric protein activates its expression, providing a selection against DNA-binding domain function. The chimeric protein also activates expression of a gene necessary for histidine prototrophy, using a second DNA-binding domain included in the chimera (lexA), providing a selection against general activator mutations. Therefore, requiring growth in the absence of histidine focuses mutations to the target DNA-binding domain. This method was applied to the DNA-binding domain of the nuclear receptor NGFI-B. Nearly all mutations obtained concurred with previous studies of NGFI-B and other nuclear receptors, verifying the functional validity of the mutational profile obtained. In addition, by coupling this selection scheme with the two-hybrid system [Chien, C.-t., Bartel, P. L., Sternglanz, R. & Fields, S. (1991) Proc. Natl. Acad. Sci. USA 88, 9578-9582], mutations that alter protein interaction domains could also be obtained.
Synthesis, properties, and hepatic metabolism of strongly fluorescent fluorodipyrrinones

Abstract From non-fluorescent 8- H fluorophenyldipyrrinones, highly fluorescent ( ϕ F 0.4–0.6) analogs have been synthesized by reaction with 1,1′-carbonyldiimidazole to bridge the dipyrrinone nitrogens and form an N , N ′-carbonyldipyrrinone (3 H ,5 H -dipyrrolo[1,2- c :2′,1′- f ]pyrimidine-3,5-dione). Amphiphilic, water-soluble 8-sulfonic acid derivatives are then obtained by reaction with concd H 2 SO 4 . The resulting fluorinated and sulfonated N , N ′-carbonyl-bridged dipyrrinones, isolated as their sodium salts, are potential cholephilic fluorescence and 19 F MRI imaging agents for use in probing liver and biliary metabolism. After intravenous injection in the rat they were excreted rapidly and largely unchanged in bile. 19 F NMR spectroscopy of a pentafluorophenyl-tosylpyrrolinone synthetic precursor exhibited rarely seen diastereotopicity.
Parallel branch and bound algorithms for quadratic zero-one programs on the hypercube architecture

We present a parallel branch and bound algorithm for unconstrained quadratic zero-one programs on the hypercube architecture. Subproblems parallelize well without the need of a shared data structure to store expanded nodes of the search tree. Load balancing is achieved by demand splitting of neighboring subproblems. Computational results on a variety of large-scale problems are reported on an iPSC/1 32-node hypercube and an iPSC/2 16-node hypercube.
Slip-line modeling of machining with a rounded-edge tool—Part I: new model and theory

The effect of tool edge roundness attracts growing attention from the international machining research community due to ever accelerating applications of precision, super-precision, micro-, and nano-machining technologies in a wide variety of modern industries. A new slip-line model for machining with a rounded-edge tool and its associated hodograph are proposed in this paper. The model consists of 27 slip-line sub-regions, each sub-region having its own physical meaning. It is demonstrated that the model simultaneously takes into account nine effects, such as the shear-zone effect and the size effect, which commonly occur in machining. Eight groups of machining parameters, such as the ploughing (parasitic or non-cutting) force and the chip up-curl radius, can be simultaneously predicted from the model. Furthermore, the model incorporates eight slip-line models previously developed for machining during the last six decades as special cases. An additional special case that involves a parallel-sided shear zone can also be derived from the new model. A mathematical formulation of the model is established based on Dewhurst and Collins's (1973) matrix technique for numerically solving slip-line problems. A purely analytical equation is proposed to predict the thickness of the primary shear zone. This equation is also employed to predict the shear strain-rate in the primary shear zone.
Engulfment mechanism of apoptotic cells

Apoptotic cells are engulfed and removed by phagocytes. This ensures proper development of the organism and can modulate immune responses. Recent studies have examined molecules on apoptotic cells, such as phosphatidylserine, which may signal for engulfment through multiple receptors. Apoptotic recognition mechanisms may vary with the apoptotic and engulfing cell type, and even with the age of the corpse.
A reactive path concept applied within a voltage control expert system

A description is presented of two rule-based techniques which predict the impact of power system voltage control devices on system bus voltages in order to aid to the decision making within a voltage control expert system. The first technique allocates to each controller a set of buses on which the controller has a significant impact. The second one determines the two controllers which are best suited to alleviate voltage problems at a given bus. Results using the IEEE-118 system are compared to load flow based results and demonstrate the feasibility of these techniques for expert system applications. >
Efficacy of solvent extraction methods for acellularization of embryoid bodies

The ability of embryonic stem cells (ESCs) to differentiate into all somatic cell types makes them an attractive cell source for regenerative medicine and tissue-engineering applications. In additi...
Sources of variability in working memory in early childhood: A consideration of age, temperament, language, and brain electrical activity

Abstract This study investigated age-related differences in working memory and inhibitory control (WMIC) in 3 1 2 -, 4-, and 4 1 2 -year-olds and how these differences were associated with differences in regulatory aspects of temperament, language comprehension, and brain electrical activity. A series of cognitive control tasks was administered to measure WMIC ability, including the Stroop-like day–night and the yes–no tasks. Baseline and task electroencephalographic data were collected. The Children's Behavior Questionnaire was used to assess caregiver perceptions of temperament with a particular interest in the effortful control and surgency factors, and language comprehension was measured with the Peabody-Picture Vocabulary Test-III. The results of this study demonstrated differential temperament-cognition relations for the three age groups, as positive associations were found between WMIC and effortful control for the 3 1 2 - and 4-year-olds and negative associations were found between WMIC and surgency for the 4 1 2 -year-olds. An increasingly robust relation between WMIC and language comprehension was demonstrated across the three age groups, as well as differential patterns of task-related brain electrical activity.
A consideration of factors underlying the selection of methods in the assessment of skeletal maturity.

The assessment of skeletal maturity is basically a method. How one makes this assessment or what one does with the assessment is dictated by the research and/or clinical problem at hand. A variety of methods have been suggested for the assessment of skeletal maturity, although the two most commonly used are the inspectional and bone specific approaches. Several of the proposed methods are considered, with primary emphasis upon the problems, factors, and/or alternatives related to the choice of one method over another.
From real to complex sign pattern matrices

This paper extends some fundamental concepts of qualitative matrix analysis from sign pattern classes of real matrices to sign pattern classes of complex matrices. A complex sign pattern and its corresponding sign pattern class are defined in such a way that they generalize the definitions of a (real) sign pattern and its corresponding sign pattern class. A survey of several qualitative results on complex sign patterns is presented. In particular, sign nonsingular complex patterns are investigated. The type of region in the complex plane representing the distribution of the determinants of the matrices in the sign pattern class of a sign nonsingular complex pattern is identified. Cyclically nonnegative complex patterns and complex patterns that are signature similar to nonnegative patterns are characterized. Extensions of sign stable and sign semistable patterns from the real to the complex case are given. Results on ray patterns are also obtained. Finally, many open questions are mentioned.
Singularity in the thermal boundary resistance between superfluid (4)He and a solid surface.

We report new measurements in four cells of the thermal boundary resistance $R$ between copper and ${}^{4}\mathrm{He}$ below but near the superfluid-transition temperature ${T}_{\ensuremath{\lambda}}$. For ${10}^{\ensuremath{-}7}\ensuremath{\le}t\ensuremath{\equiv}{1\ensuremath{-}T/T}_{\ensuremath{\lambda}}\ensuremath{\le}{10}^{\ensuremath{-}4}$ fits of ${R\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}R}_{0}{t}^{{\ensuremath{-}x}_{b}}{+R}_{B}$ to the data yielded ${x}_{b}\ensuremath{\simeq}0.18$, whereas a fit to theoretical values based on the renormalization-group theory yielded ${x}_{b}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.23$. Alternatively, a good fit of the theory to the data could be obtained if the amplitude of the prediction was reduced by a factor close to 2. The results raise the question whether the boundary conditions used in the theory should be modified.
Diet and psoriasis, part II: Celiac disease and role of a gluten-free diet

Patients with psoriasis have been shown to have a higher prevalence of other autoimmune diseases including celiac disease, a condition marked by sensitivity to dietary gluten. A number of studies suggest that psoriasis and celiac disease share common genetic and inflammatory pathways. Here we review the epidemiologic association between psoriasis and celiac disease and perform a meta-analysis to determine whether patients with psoriasis more frequently harbor serologic markers of celiac disease. We also examine whether a gluten-free diet can improve psoriatic skin disease.
Management of Ascending Aortic Aneurysm Complicating Coarctation of the Aorta

Four patients with coarctation of the aorta complicated by an aneurysm of the ascending aorta are described. One patient, treated only medically, died suddenly. For the 3 patients who underwent operation, management was similar. Pharmacological control of blood pressure and repair of the aortic coarctation to achieve anatomical reduction in afterload (stage I) were followed after an interval of one to five weeks by surgical repair of the ascending aortic aneurysm (stage II). Initial repair of the coarctation relieves proximal hypertension, thereby decreasing the chance of progressive dissection or rupture of the aneurysm. It also permits safe arterial cannulation for perfusion during correction of the aneurysm in the second stage. In patients not requiring valve replacement in stage II, continued long-term follow-up for progression of aortic valvular disease appears to be necessary.
Effect of recreational physical activities on the development of knee osteoarthritis in older adults of different weights: The Framingham Study

Objective To evaluate the long-term effect of recreational exercise on the development of knee osteoarthritis (OA) in a community-based cohort of older adults, many of whom were overweight or obese. Methods Subjects were asked about recreational activities including walking or jogging for exercise and working up a sweat, and were asked to compare their activity levels with others. Subjects were then asked about knee pain and weight-bearing anteroposterior and lateral knee radiographs were obtained. Approximately 9 years later, subjects were reexamined for OA. Radiographs were read for OA features in both tibiofemoral and patellofemoral compartments and were scored for tibiofemoral joint space narrowing. To evaluate incident OA, we excluded knees with OA at baseline for all analyses and focused on 3 knee-specific outcomes: incident radiographic OA, symptomatic OA, and tibiofemoral joint space loss. After adjusting for age, sex, body mass index (BMI), knee injury history, and correlation between knees, we evaluated the association of each recreational activity with OA development. Results A total of 1,279 subjects underwent both baseline and followup examinations (mean age at baseline 53.2 years). Neither recreational walking, jogging, frequent working up a sweat, nor high activity levels relative to peers were associated with a decrease or increase in risk of OA. Joint space loss was also unaffected by activity. Persons with BMI above the median (27.7 kg/m2 for men and 25.7 kg/m2 for women; mean BMI >30 kg/m2 for both) had no increases in risk of OA by different type of activity. Conclusion Among middle-aged and elderly persons without knee OA, many of whom were overweight, recreational exercise neither protects against nor increases risk of knee OA.
Preparation of targeted microbubbles: ultrasound contrast agents for molecular imaging

Targeted ultrasound contrast agents can be prepared by attaching targeting ligands to the lipid, protein or polymer shell coating of gas-filled microbubbles. These materials are stable on storage, fully biocompatible and can be administered parenterally. Detection of microbubble contrast agents by ultrasound is very efficient (single particles with picogram mass can be visualized). Covalent or noncovalent binding techniques can be used to attach targeting ligands. Ligand-carrying microbubbles adhere to the respective molecular targets in vitro and in vivo. Several biomechanical methods are available to improve targeting efficacy, such as the use of a flexible tether spacer arm between the ligand and the bubble, and the use of folds on the microbubble shell, that project out, enhancing the contact area and increasing the length of the lever arm.
Changes in the activity of cholinesterase of nervous tissue under the influence of constant current.

POLARIZATION of nervous tissue with constant current leads to the accumulation of acetylcholine at the cathode and to its diminution at the anode. These facts may be explained as the result of polar changes either in the synthesis of acetylcholine, or in the intensity of its enzymic breakdown. To test the validity of the second assumption, we have investigated the influence of constant current upon the activity of cholinesterase in nervous tissue. The experiments were performed with the sciatic nerve of frogs and dogs and with the cerebral cortex of dogs.
Wind turbine blade shear web disbond detection using rotor blade operational sensing and data analysis.

A wind turbine blade's structural dynamic response is simulated and analysed with the goal of characterizing the presence and severity of a shear web disbond. Computer models of a 5 MW offshore utility-scale wind turbine were created to develop effective algorithms for detecting such damage. Through data analysis and with the use of blade measurements, a shear web disbond was quantified according to its length. An aerodynamic sensitivity study was conducted to ensure robustness of the detection algorithms. In all analyses, the blade's flap-wise acceleration and root-pitching moment were the clearest indicators of the presence and severity of a shear web disbond. A combination of blade and non-blade measurements was formulated into a final algorithm for the detection and quantification of the disbond. The probability of detection was 100% for the optimized wind speed ranges in laminar, 30% horizontal shear and 60% horizontal shear conditions.
Compensatory renal hypertrophy following uninephrectomy is calcineurin-independent.

Calcineurin is a calcium-dependent phosphatase that is involved in many cellular processes including hypertrophy. Inhibition or genetic loss of calcineurin blocks pathological cardiac hypertrophy and diabetic renal hypertrophy. However, calcineurin does not appear to be involved in physiological cardiac hypertrophy induced by exercise. The role of calcineurin in a compensatory, non-pathological model of renal hypertrophy has not been tested. Therefore, in this study, we examined activation of calcineurin and the effect of calcineurin inhibition or knockout on compensatory hypertrophy following uninephrectomy (UNX). UNX induces ~15% increase in the size of the remaining kidney; the data show no change in the generation of reactive oxygen species (ROS), Nox4 or transforming growth factor-β expression confirming the model as one of compensatory hypertrophy. Next, analyses of the remaining kidney reveal that total calcineurin activity is increased, and, to a lesser extent, transcriptional activity of the calcineurin substrate nuclear factor of activated T cell is up-regulated following UNX. However, inhibition of calcineurin with cyclosporine failed to prevent compensatory renal hypertrophy. Likewise, hypertrophy was comparable to WT in mice lacking either isoform of the catalytic subunit of calcineurin (CnAα−/− or CnAβ−/−). In conclusion, similar to its role in the heart, calcineurin is required for pathological but not compensatory renal hypertrophy. This separation of signalling pathways could therefore help further define key factors necessary for pathological hypertrophy including diabetic nephropathy.
Future crop tree damage in a certified community forest in southwestern Amazonia

Abstract Field studies in Acre, Brazil assessed logging impacts of a certified community timber management project. The main objectives of the study were: (1) to determine if damage incidence to future crop trees (FCTs; ≥20 cm diameter at breast height (dbh)) differs between (a) forest with and without bamboo (Guadua spp.), and (b) trees with and without lianas; (2) to what extent harvesting can be conducted more intensely (m3ha−1), without incurring greater FCT damage; and (3) to what extent marking diminishes FCT damage. Full inventories of FCTs of 50 commercial species complexes were conducted before and after logging in 50 m-radius zones of impact around each designated harvest tree in three 10 ha (200 m × 500 m) logging blocks. We also mapped all forested areas potentially influenced by logging, including skid trails, log landings and felling gaps, throughout the 30 ha logged. More than 28% of the forest area was disturbed by logging, with 12.1% in skid trails and 16.8% in gap clearings, indicating that the forest gap mosaic can be significantly altered even when reduced-impact logging guidelines are followed. Overall, 15% of FCTs inventoried were damaged. Damage rates were not significantly reduced by marking treatment, location in bamboo-dominated forest, or liana load on FCT damage. Harvest intensity did not influence the probability of FCT damage. For future studies, it would be prudent to address impacts of timber extraction on other livelihood activities, such as non-timber forest product collection, particularly in such regions as the Brazilian Amazon, where many communities are attempting to integrate a suite of income-generating activities.
Newer applications for Crossflow Membrane Filtration

Abstract Traditionally, Crossflow Membrane Filtration has been used to concentrate and purify solutions of macromolecules. Typical applications include protein concentration in the Food, Dairy and Pharmaceutical industries. In recent years, the use of membranes to remove suspended solids and other unwanted components from liquid streams has been commercially proven. Such applications include clarification of fruit juices and other beverages as well as depyrogenation of water for both the Pharmaceutical and Electronics industry. Continuing development of larger pore microfiltration membranes are expanding the range of application to the removal of unwanted solids from solutions of proteins such as gelatin. This paper highlights recent data on the use of Croosflow Membrane Filtration in processing beverages, gelatin and inorganic slurries.
User characteristics and out-of-pocket expenditures for progestin-only versus combined oral contraceptives.

Abstract Background Little is known about the proportion of oral contraceptive pill (OCP) users that use progestin-only pills (POPs), factors associated with POP use, and whether out-of-pocket expenditures and dispensing patterns are similar to combined oral contraceptives (COCs). Study Design Observational cohort using 1996–2008 Medical Expenditure Panel Surveys. Results Among all OCP users, 4% used POPs and changed little between 1996 and 2008. Women were more likely to use POPs if they received postpartum care (p Conclusion POP use is very low in the United States. POP users obtained fewer packs per purchase compared with COC users, suggesting that POP may be used as transitional OCPs, particularly during the postpartum period.
Contra-thermodynamic behavior in intermolecular hydrogen transfer of alkylperoxy radicals.

Quantum chemical investigation of bimolecular hydrogen transfer involving alkylperoxy radicals, a key reaction family in the free-radical oxidation of hydrocarbons, was performed to establish structure–reactivity relationships. Eight different reactions were investigated featuring four different alkane substrates (methane, ethane, propane and isobutane) and two different alkylperoxy radicals (methylperoxy and iso-propylperoxy). Including forward and reverse pairs, sixteen different activation energies and enthalpies of reaction were used to formulate structure–reactivity relationships to describe this chemistry. We observed that the enthalpy of formation of loosely bound intermediate states has a strong inverse correlation with the overall heat of reaction and that this results in unique contra-thermodynamic behavior such that more exothermic reactions have higher activation barriers. A new structure–reactivity relationship was proposed that fits the calculated data extremely well: EA=Eo+αΔHrxn where α=−0.10 for ΔHrxn 0 and Eo=3.05 kcal mol−1.
The influence of high application rates of polyacrylamide on microbial metabolic potential in an agricultural soil

Abstract Water soluble anionic polyacrylamide (PAM) is a highly effective erosion preventing and infiltration enhancing polymer, when applied at rates of 1–10 g m −3 in furrow irrigation water. PAM greatly reduces sediment, nutrients, pesticides and coliform bacteria in irrigation runoff. There has been some concern about the potential for PAM accumulation to affect microbial ecology. We ran a long-term study applying massive quantities of PAM to soil and monitored its impact on soil microbial potential. In June, July and August, we measured active soil bacterial and fungal biomass and microbial diversity in soils receiving 0 (control), 2691 and 5382 kg active ingredient (ai) PAM ha −1 . Active bacterial biomass in soil was 20–30% greater in the control treatment than in soil treated with 2691 or 5382 kg ai PAM ha −1 in June and August, but not July. Active fungal biomass in soils was 30–50% greater in the control treatment than soil treated with 2691 or 5382 kg ai PAM ha −1 in June and July, but not August. Active microbial biomass in soil was 27–48% greater in the untreated control than soil treated with 2691 or 5382 kg ai PAM ha −1 except in June. Whole soil fatty acid profiles showed no discernible change in the soil microbial community due to either of the PAM treatments at any sampling time. Analysis of nutritional characteristics using Biolog GN plates, however, yielded an apparent separation of the non-amended control soils from those plots receiving the high PAM application rate in June, but not in July or August. In contrast, comparisons of the three sampling times by both the fatty acid and Biolog analyses indicated that the microbial metabolic potential present in June were different from those sampled in July and August. Although PAM application to soil or irrigation water in some cases may reduce active bacterial and fungal biomass it does not seem to appreciably affect the soil microbial metabolic potential.
Ventral Lamina Terminalis Mediates Enhanced Cardiovascular Responses of Rostral Ventrolateral Medulla Neurons During Increased Dietary Salt

Increased dietary salt enhances sympathoexcitatory and sympathoinhibitory responses evoked from the rostral ventrolateral medulla (RVLM). The purpose of the present study was to determine whether n...
Durability of YZA ceramic foams in a porous burner

The durability of YZA cellular ceramic foams was investigated in the demanding environment of an instrumented porous burner. Following exposure to the combustion environment, the ceramic foam coupons suffered moderate damage. Coupons exposed to extended duration tests in the burner did not show additional damage compared to coupons exposed to short duration tests indicating that damage occurred during start-up, when temperature gradients were most severe. To compare the results of the burner tests to conventional thermal shock experiments, samples were also exposed to a water quench test. Coupons removed from the burners and coupons exposed to the water quench from high temperatures exhibited similar failure morphologies. In both cases a marked transition in failure morphology was observed as the magnitude of the peak temperatures and thermal gradients were increased. Chemical analysis combined with these thermal shock measurements show that damage sustained by the foams in the burner results from thermal shock and not from chemical degradation.
Microtubule disruption, not calpain-dependent loss of MAP2, contributes to enduring NMDA-induced dendritic dysfunction in acute hippocampal slices.

Abstract Brief exposure to excitotoxic agonists can result in substantial loss of the microtubule-associated protein MAP2 from neuronal dendrites, and accumulation in somata. A possible mechanism underling MAP2 loss is the activation of the calcium-dependent protease calpain by excessive dendritic Ca 2+ -loading. The present study examined mechanisms of MAP2 redistribution and loss of synaptic efficacy in the CA1 region of acutely prepared hippocampal slices. Brief NMDA exposure resulted in persistent and profound inhibition of postsynaptic potentials, and loss of MAP2 from dendritic compartments. When Ca 2+ was removed during NMDA exposure, synaptic potentials recovered significantly during NMDA washout, and MAP2 loss was reduced. Calpain inhibition with MDL 28,170 (20 μM) did not prevent the loss of synaptic potentials, nor did it attenuate the initial aggregation of MAP2 into irregular dendritic swellings. However MDL 28,170 did reduce subsequent MAP2 loss from abnormal dendritic aggregates. Pre-exposure of slices to taxol (100 nM) effectively prevented microtubule depolymerization following NMDA exposure, as well as MAP2 disorganization and loss from apical dendrites. Slices treated with taxol also exhibited substantial recovery of synaptic potentials after transient NMDA stimulus. These results demonstrate a close correspondence between the maintained localization of MAP2 in apical dendrites and the recovery of postsynaptic potentials following transient NMDA exposure. In addition, it appears that rather than underlying the initial disruption of microtubule structure via MAP2 proteolysis, calpain activity instead may contribute to the degradation of irregularly aggregated MAP2 observed following microtubule depolymerization.