cssi/SciSciGPT-SciSciNet huggingface dataset:
Incentives to Transfer Patients Under Alternative Reimbursement Mechanisms

Alternative hospital reimbursement systems may influence the frequency and timing of patient transfers between hospitals as well as the patient's length of stay. This paper examines the characteristics of reimbursement systems that result in efficient and equitable transfers and efficient lengths of stay. Except in special cases, there is a tradeoff between achieving these three objectives. If patient benefits or receiving hospital profits are undervalued, then achieving efficient transfer decisions generally requires the reimbursement of the sending hospital to depend upon some weighted average of its own marginal costs and the costs of the receiving hospital.
Linguistic and Visual Cognition: Verifying Proportional and Superlative Most in Bulgarian and Polish

The verification of a sentence against a visual display in experimental conditions reveals a procedure that is driven solely by the properties of the linguistic input and not by the properties of the context (the set-up of the visual display) or extra-linguistic cognition (operations executed to obtain the truth value). This procedure, according to the Interface Transparency Thesis (ITT) (Lidz et al. in Nat Lang Semant 19(3):227---256, 2011), represents the meaning of an expression at the interface with the `conceptual-intentional' system (Chomsky in The minimalist program. MIT Press, Cambridge, 1995). My experiments provide support for the ITT by replicating in Polish and in Bulgarian the findings of Lidz et al. (Nat Lang Semant 19(3):227---256, 2011) for the English quantifier most. We also obtain new evidence that participants are prompted to switch between verification procedures by a change in the linguistic input (a different superlative quantifier entailed by most), but not by a change in the visual input. Thus, the motivation for the subconscious switch in procedures is not to maximize efficiency. Participants use the procedure associated with each quantifier, and in effect, the same display is verified differently depending on which information the visual system is instructed to use by the semantic representation of the sentence.
Relationships among derivatives of the integrals in the calculation of the gradient of the electronic energy with respect to the nuclear coordinates

The use of the translational invariance property of molecular integrals is extended by its combination with the closely related transformation properties under infinitesimal rotations. This further reduces the number of truly linearly independent derivatives of the molecular integrals that require calculation in obtaining the gradient of the electronic energy. The detailed linear equations that yield the linearly dependent derivatives in terms of the ’’independent’’ derivatives are presented.
Controls on niche stability in geologic time: congruent responses to biotic and abiotic environmental changes among Cincinnatian (Late Ordovician) marine invertebrates

The set of environmental conditions under which a taxon can survive and maintain viable populations, known as the ecological niche, is a fundamental determinant of a taxon's distribution. Because of the central importance of ecological niches, they have been assumed to remain relatively stable during intervals of morphological stasis. However, the assumption of niche stability has rarely been tested directly with fossil data spanning multiple temporal intervals. Thus, the conditions under which this assumption is likely to be accurate are not well understood. In this study, we use ecological niche modeling (ENM) to reconstruct the ecological niche for 11 genera of marine benthos (crinoids, trilobites, molluscs, bryozoans, and corals) from the Type Cincinnatian Series (Late Ordovician, Katian Stage) across nine temporal intervals spanning approximately three million years. This interval includes both abiotic environmental change (gradual sea-level fall) and biotic change (rapid pulses of the Richmondian Invasion), thus allowing the relative effect of different environmental perturbations to be constrained. A previous symmetrical analysis of niche stability of brachiopod species recovered an increase in niche evolution following the Richmondian Invasion. Herein we test the generality of the brachiopod pattern within the community. Niche stability was evaluated in geographic space, ecological space, and niche parameter space. Niche stability varied through time; during the Pre-Invasion interval, taxa exhibited niche stability during gradual shallowing of sea level in the basin, whereas niche evolution became more common during the Richmondian Invasion. Taxa adjusted to the increased competition by altering aspects of their niche. Notably, surviving taxa contracted their niche into a subset of their previous niche parameters. This represents an adaptive response to increased competition for resources with the newly established invader taxa, and it was employed most successfully by generalist taxa. Patterns of niche evolution were congruent between clades, among feeding styles, and across taxonomic levels.
Characterization of Titania Loaded V-, Fe-, and Cr-Incorporated MCM-41 by XRD, TPR, UV−vis, Raman, and XPS Techniques

Transition metal (Me = V, Fe, and Cr) incorporated into MCM-41 mesoporous molecular sieves (Si/Me = 80) have been synthesized by hydrothermal methods and were loaded with TiO2 utilizing a sol−gel technique. These materials were found (refs 22, 23) to be photoactive for the destruction of organics with visible light. A combination of various physicochemical techniques such as N2 physisorption, O2 chemisorption, diffuse reflectance UV−vis (DR−UV−vis), X-ray diffraction (XRD), Raman, temperature program reduction (TPR), and X-ray photoelectron spectroscopy (XPS) were used to characterize the chemical environment of these transition metals in the prepared photocatalysts. The dispersion of transition metals as determined by O2 chemisorption suggests that they are well dispersed inside the MCM-41 framework, but the dispersion values decreased with the loading of TiO2. This indicates that the loaded titania promotes the transformation of incorporated metal ions into different phases. DR−UV−vis spectra of the Me-...
Interruptions in the Real World: Examining the Role of Internal Versus External Interruptions in a Hospital Pharmacy

Interruptions are a common cause of errors in the pharmacy, cited as being responsible for as much as 43% of the error that occurs in medication administration. The purpose of this study was to explore the characteristics of interruptions in a hospital pharmacy setting and to determine the extent to which existing theories of interruptions can account for our findings. As a central feature of this work, we chose to examine a characteristic of interruptions seldom examined in laboratory studies, which is the source of the interruption. The findings from this study begin to suggest that the theories developed to explain the cognitive mechanisms by which people resume from interruptions do apply to the pharmacy setting. Further, the data suggest that preservation of the system state has a protective effect on performance.
Effect of interface bonding on spin-dependent tunneling from the oxidized Co surface

We demonstrate that the factorization of the tunneling transmission into the product of two surface trans- mission functions and a vacuum decay factor allows one to generalize Julliere's formula and explain the meaning of the ''tunneling density of states'' in some limiting cases. Using this factorization we calculate spin-dependent tunneling from clean and oxidized fcc Co surfaces through vacuum into Al using the principal- layer Green's-function approach. We demonstrate that a monolayer of oxygen on the Co~111! surface creates a spin-filter effect due to the Co-O bonding which produces an additional tunneling barrier in the minority-spin channel. This changes the minority-spin dominated conductance for the clean Co surface into a majority-spin dominated conductance for the oxidized Co surface. In this paper we report the results of first-principles cal- culations of SDT from clean and oxidized Co surfaces through vacuum into Al and demonstrate the crucial role of the bonding between Co and O atoms at the surface. This system was chosen for investigation because the MTJ's based on alumina have predominantly O-terminated Co/Al2O3 interfaces. 10 By replacing alumina by vacuum we can ignore the complexity of the atomic structure of the amorphous alumina and focus on effects of surface oxida- tion. Moreover, this system can be directly studied using spin-polarized STM. 11 We show that a monolayer of oxygen on the Co surface creates a spin-filter effect due to the Co-O bonding by pro- ducing an additional tunneling barrier in the minority-spin channel. This reverses the sign of the SP from negative for the clean Co surface to positive for the oxidized Co surface revealing the decisive role of interface bonding in SDT.
Neutral C19-steroids and steroid sulfates in human pregnancy IV. Isolation and identification of unconjugated dehydroepiandrosterone and 16α-hydroxydehydroepiandrosterone from pooled cord blood

Abstract Identification of unconjugated dehydroepiandrosterone (D) and 16α-hydroxydehydroepiandrosterone (16α-OH-D) isolated from 500 ml of cord plasma obtained from mixed arterial and venous cord blood collected after vaginal delivery at term is presented. The identification is based upon in vitro placental conversion of D and 16α-OH-D to 17β-estradiol and estriol respectively, further on formation of D acetate and 16α-OH-D diacetate and their thiosemicarbazones, and finally on reduction of the acetates and repeat acetylation. All acetates were doubly labelled and chromatographed to constant 3 H/ 14 C ratios. Constant ratios were also obtained in recrystallizations of D acetate and 16α-OH-D diacetate after reversed isotope dilution.
Proximal row carpectomy with a dorsal capsule interposition flap

Arthritis of the wrist can be a debilitating condition that presents with progressive pain and loss of motion. A proximal row carpectomy (PRC) is indicated for the management of wrist arthritis and is designed to improve pain while maintaining motion. It involves excision of the scaphoid, lunate, and triquetrum with the formation of a new articulation between the base of the capitate and the lunate fossa of the distal radius. The PRC is a technically straightforward procedure that can produce reliable results. It is contraindicated in cases with midcarpal arthritis and degeneration of the base of the capitate. In addition, there is a question of durability of the new articulation between the capitate and the lunate fossa of the distal radius. The use of interposition tissue can potentially decrease joint contact pressures and improve long-term durability. A PRC technique with the use of an interposition flap based on the dorsal capsule of the distal radius is presented.
Concurrent Water-Drinking on FI and CRF Food-Reinforcement Schedules in the Rhesus Monkey:

Concurrent drinking was recorded in 3 rhesus monkeys for 5 sessions in which bar-pressing was maintained on a CRF schedule of food reinforcement and for 10 sessions on an FI 1-min. reinforcement sc...
Digital adaptive flight control design using single stage model following indices

Simple mechanical linkages are often unable to cope with many control problems associated with high performance aircraft. This has led to the development of digital fly-by-wire control systems and in particular digital adaptive controllers that can be efficiently adjusted during system operation. To this effect, a control law has been derived based upon the minimization of a single stage weighted combination of control energy and the squared error between the states of a linear plant and model. This control logic is interfaced with an on-line weighted least squares estimator and a Kalman state filter. The utility of the resultant control system is illustrated by its application to the linearized dynamics of a typical fighter aircraft.
Linear ablation of the mitral isthmus during atrial fibrillation ablation increases the incidence of left atrial tachycardia

SESSION 9: DEVICES III: Treatment of Atrial Tachyarrhythmias with Implantable Devices Thursday, May 5, 2005 11:15 a.m.–12:45 p.m.
"Embracing the Second Best?Synchronization of Reforms Rhythms, Slack, and Firm Performance"

We analyze the understudied impact of synchronization of reforms rhythms on the performance of transition economy firms. We argue that higher synchronization of reforms rhythms improves the firms’ performance due to timing synergies among the different reforms types. Additionally, we propose that excess high-discretion slack further strengthens the performance benefits from a higher synchronization of reforms rhythms because it allows the transition economy firms to more quickly adapt to their changing institutional environment. Thus, we extend the institution-based view of the firm by shifting its traditional focus on institutional differences across countries to a new research direction that accounts explicitly for the timing of implementation—concurrent or sequential—of the different types of reforms rhythms within a country over time. Our test on a sample of 430 firms from 13 transition economies during 1991-2009 supports our arguments.
Cation exchange chromatography provides effective retrovirus clearance for antibody purification processes

One measure taken to ensure safety of biotherapeutics produced in mammalian cells is to demonstrate the clearance of potential viral contaminants by downstream purification processes. This paper provides evidence that cation exchange chromatography (CEX), a widely used polishing step for monoclonal antibody (mAb) production, can effectively and reproducibly remove xMuLV, a retrovirus used as a model of non-infectious retrovirus-like particles found in Chinese hamster ovary cells. The dominant mechanism for xMuLV clearance by the strong cation exchanger, Fractogel SO, is by retention of the virus via adsorption instead of inactivation. Experimental data defining the design space for effective xMuLV removal by Fractogel SO with respect to operational pH, elution ionic strength, loading, and load/equilibration buffer ionic strength are provided. Additionally, xMuLV is able to bind to other CEX resins, such as Fractogel COO− and SP Sepharose Fast Flow, suggesting that this phenomenon is not restricted to one type of CEX resin. Taken together, the data indicate that CEX chromatography can be a robust and reproducible removal step for the model retrovirus xMuLV. Biotechnol. Bioeng. 2012;109: 157–165. © 2011 Wiley Periodicals, Inc.
Matching Performance For Multiple Wafer Steppers Using An Advanced Metrology Procedure

This paper describes a methodology based on advanced metrology to quantify the overlay performance of individual wafer steppers and a means to optimize their matching. Use of accurate two point through the lens alignment directly referenced to the reticle and a three axis interferometrically controlled X-Y-0 stage permits full characterisation of the individual machine overlay errors. With the help of parameters determined in an extended metrology model of the microlithographic lens distortions and the wafer stage grid distortions one can automatically adjust corresponding machine servo-mechanisms for optimum matching. The model can be used to calculate and predict the systematic errors between random pairs of machines rather thav having to directly measure all pairs, so ensuring efficient, high quality matching. Results of an eight machine matching experiment demonstrating the model's validity and effective use on PAS 2500 wafer steppers are described.
Vagal intraganglionic laminar endings and intramuscular arrays mature at different rates in pre-weanling rat stomach

Abstract To assess whether vagal afferents in the gastrointestinal (GI) tract mature postnatally and differentiate at different rates, potentially reflecting the changing functional requirements of weaning and independence, the vagal afferent innervation of the stomach was inventoried in pre-weanling and adult rats. Wheatgerm agglutinin–horseradish peroxidase was injected into the nodose ganglia of 9-day-old and adult rats, and after tracer transport, the animals were sacrificed. Their stomachs were prepared as wholemounts and processed with tetramethylbenzidine. Inventories were obtained with a counting grid that was systematically positioned throughout the wholemounts by the use of a sampling template that was adjusted for stomach size and shape. Densities in the gastric antrum, corpus, and forestomach were determined for (1) afferent bundles, (2) individual fibers separated from the bundles and presumably located near their targets, (3) differentiated intraganglionic laminar endings (IGLEs) associated with myenteric ganglia, and (4) differentiated intramuscular arrays (IMAs) situated within the smooth muscle layers. In pre-weanling rats, which were 10 days old at perfusion, the distributions of vagal bundles and fibers were similar to those of adults, suggesting that the basic vagal architecture develops early. Differentiated IGLEs were also distributed in a mature pattern in 10 day olds, whereas few IMAs had yet been distributed and differentiated in the forestomach of the pre-weanlings. The authors hypothesize that these different developmental patterns for the two types of vagal afferents are consistent with their putative functional roles as, respectively, mechanoreceptors (IGLEs) that coordinate rhythmic motor function needed early for the digestion of milk and stretch receptors (IMAs) needed later as the GI tract matures for the transition to solid food at weaning.
Measurements of the streamwise vortical structures in a plane mixing layer

The 3D structure of a plane two-stream mixing layer of velocity ratio 0.6 and originating from laminar initial boundary layers was investigated through direct measurements made in a specially constructed mixing-layer wind tunnel. The main objective of the study was to establish quantitatively the presence and the role of the secondary streamwise vortex structure (of the kind that has been shown in past flow visualization investigations to ride among the primary spanwise vortices) in the development of a plane turbulent mixing layer at relatively high Reynolds numbers. Results indicate that the instability leading to the formation of streamwise vortices is initially amplified just downstream of the first spanwise roll-up. The streamwise vortices, which first appear in clusters containing vorticity of both signs, realign further downstream to form counterrotating pairs. Due to the amalgamation of like-sign vortices, the streamwise vortex spacing increases in a stepwise fashion.
Stability of microsatellites in myeloid neoplasias

Microsatellites are short, repeated DNA sequences that exist throughout the genome. Instability of these sequences, associated with defects in the DNA mismatch repair system, is the hallmark of hereditary non-polyposis colorectal cancer (HNPCC), and is also found in many sporadic cancers. Although many types of solid tumors exhibit this type of genetic instability, its involvement in hematologic cancers is less evident. We have investigated whether microstatellite instability (MSI) is involved in the transformation of myeloid cells to myelodysplastic syndrome (MDS) and/or acute myelogenous leukemia (AML). Both de novo and treatment-associated neoplasias were studied. Only one example of MSI was found in 48 patients, using a panel of 14 different microsatellite loci consisting of repeats of one to four base pairs. These results suggest that the genes responsible for MSI are not involved in the transformation of normal myeloid cells to MDS or AML.
Triazole−Au(I) Complexes: A New Class of Catalysts with Improved Thermal Stability and Reactivity for Intermolecular Alkyne Hydroamination

A series of 1,2,3-triazole-bound cationic Au(I) catalysts have been synthesized, and their structures have been characterized by X-ray crystallography. Variable-temperature NMR studies revealed dynamic triazole−Au cation coordination in solution. Reaction profiles clearly indicated that these new catalysts possess much better thermal stability than literature-reported Au catalysts, including IPrAu·NTf2. By application of these catalysts, challenging intermolecular hydroaminations were achieved with less-reactive internal alkynes and unprotected aliphatic amines, giving excellent yields with low catalyst loading.
Individual differences and instructional design

This paper is based on a presentation given at the Convention of the Association for Educational Communications & Technology, Miami, April 25-29, 1977. The research reported herein was supported by Office of Naval Research Contract No. N00014-75-C-0882. The views and conclusions contained in this document are those of the author and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the Office of Naval Research, the Advanced Research Projects Agency, or the United States Government.
FIND-SITES OF THE DEAD SEA SCROLLS

published and have been labeled as coming from particular find-sites. While many texts can be assigned to a particular find-site with great certainty, there is uncertainty about where some texts were found. Some scholars have questioned whether the origin of a particular text has been appropriately identified. James Davila, for instance, agrees with the earlier suggestion of F.M. Cross that 4Q2 Genb "may not come from Qumran."2 Arguments given to support this include the poor condition of the fragments, the late script, the fact that the text is virtually identical to the Masoretic text and that no fragment of this document was found in the controlled excavation of Cave 4 at Qumran. He suggests that the text may have come from a site such as Murabbacat. He concludes: "Thus, the question must remain open that this manuscript possibly came from another cave and was inadvertently mixed with Cave 4 manuscripts by the Bedouin."3 This example shows that there are doubts about some texts and raises the question of what criteria should be used to determine the precise find-site of a particular text. Davila' s arguments presuppose that there is a well-defined corpus at Qumran, that the characteristics of this corpus are clearly known and that when a particular text does not fit these characteristics it is reasonable to assume that this text does not belong to Qumran.
Analysis and minimization techniques for total leakage considering gate oxide leakage

In this paper we address the growing issue of gate oxide leakage current (I/sub gate/) at the circuit level. Specifically, we develop a fast approach to analyze the total leakage power of a large circuit block, considering both I/sub gate/ and subthreshold leakage (I/sub sub/). The interaction between I/sub sub/ and I/sub gate/ complicates analysis in arbitrary CMOS topologies and we propose simple and accurate heuristics based on table look-ups to quickly estimate the state-dependent total leakage current within 1% of SPICE. We then make several observations on the impact of I/sub gate/ in designs that are standby power limited, including the role of device ordering within a stack and the differing state dependencies for NOR vs. NAND topologies. Based on these observations, we propose the use of pin recording as a means to reduce I/sub gate/ due to the dependencies of gate leakage on stack node voltages.
A process-tracing approach toward understanding supervisors' SDy estimates: Results from five job classes

Schmidt, Hunter, McKenzie & Muldrow (1979) have proposed a method for using supervisors' estimates of the value of various levels of job performance to calculate the standard deviation of performance in money values—SDy. The use of this procedure has become popular in recent years. However, little is known about how supervisors make such estimates. This study employed a process-tracing approach to identify the types of information supervisors used to make their estimates. Several different types of information (e.g. salary, overall job responsibilities, work attitudes) were cited consistently across five job classes. Other sources of information were tied more uniquely to certain jobs. Supervisors' percentile estimates were found to conform rather closely to minimum, mean and maximum job class salary levels. Furthermore, more experienced supervisors tended to use salary information and existing organizational documentation for making such estimates. Implications of these findings were discussed in terms of the use of SDy estimates in practice and directions for future research.
Do the Medicaid and Medicare programs compete for access to health care services? A longitudinal analysis of physician fees, 1998–2004

As the demand for publicly funded health care continues to rise in the U.S., there is increasing pressure on state governments to ensure patient access through adjustments in provider compensation policies. This paper longitudinally examines the fees that states paid physicians for services covered by the Medicaid program over the period 1998–2004. Controlling for an extensive set of economic and health care industry characteristics, the elasticity of states’ Medicaid fees, with respect to Medicare fees, is estimated to be in the range of 0.2–0.7 depending on the type of physician service examined. The findings indicate a significant degree of price competition between the Medicaid and Medicare programs for physician services that is more pronounced for cardiology and critical care, but not hospital care. The results also suggest several policy levers that work to either increase patient access or reduce total program costs through changes in fees.
Respiration and Dissolution of Iron(III)-Containing Clay Minerals by Bacteria

A quantitative study of microbial clay mineral reduction coupled to the oxidation of organic carbon was carried out using an Fe(III)-reducing bacterium (Shewanella putrefaciens strain MR-1). Total CO2 production, organic acid depletion, and Fe(III) reduction were measured in the same cultures with formate or lactate as the carbon source and clay as the sole electron acceptor. Mean ratios of 1.6:1 and 4.9:1 were observed for structural Fe(III) reduction coupled to formate oxidation and lactate oxidation, respectively. When organic ligands were added under similar culture conditions, the extent of clay reduction was enhanced up to 2-fold in the order of nitrilotriacetic acid (NTA) > oxalate > citrate > malate. Further, dissolution of the clay mineral structure was inferred as dissolved Fe(II) comprised up to 50% of the total clay-bound Fe reduced in cultures to which organic ligand was added. Here we provide the first direct measurements which show that (1) bacteria may couple the respiration of Fe(III) bou...
Effect of Hydrochlorothiazide Therapy on Cardiac Arrhythmias in African-American Men With Systemic Hypertension and Moderate to Severe Left Ventricular Hypertrophy

The effect of hydrochlorothiazide therapy on ventricular arrhythmias was studied in 45 hypertensive African-American men with moderate to severe left ventricular (LV) hypertrophy. After medication washout, patients were treated with placebo followed by hydrochlorothiazide. Clinical, biochemical, and 48-hour ambulatory electrocardiographic data was collected after each treatment phase. Signal-averaged electrocardiograms were recorded in a subgroup of 24 patients. Average LV posterior wall thickness was 15 +/- 1.1 mm, septum 16 +/- 2 mm, LV mass 420 +/- 90 g, and LV mass index 212 = 51 g/m2. Systolic blood pressure (BP) was 168 +/- 18 mm Hg after the placebo phase and 146 +/- 15 mm Hg after hydrochlorothiazide; diastolic BP was 103 +/- 6 mm Hg and 89 +/- 9 mm Hg, respectively. Serum potassium decreased significantly from 4.2 +/- 0.4 mmol/L to 3.7 +/- 0.6 mmol/L after hydrochlorothiazide therapy. The average hourly incidence of ventricular premature contractions was 22 with placebo and 25 with hydrochlorothiazide. There were 3 and 1 couplets and 0.2 and 0.2 runs of ventricular tachycardia per patient per hour, respectively. Variables of signal-averaged electrocardiography did not differ between the 2 treatments. Thus, in hypertensive African-American men with moderate to severe LV hypertrophy, hydrochlorothiazide does not worsen ventricular arrhythmias or signal-averaged electrocardiographic variables.
Organizational survival and alignment: insights into conflicting perspectives on the role of the IT professional

Different organizational theories clearly define critical organizational activities necessary for organizational survival. Recent attention to "hybrid" research that links organizational theory with MIS research has been proposed to lend new insights into strategic alignment of IT (Orlikowski & Barley, 2000; Zmud, 2002). One gap still to be addressed relates to role expectations and skills required by the IT professional according to different organizational theories. Much of the literature on strategic alignment of IT emphasizes the value provided by the IT artifact or focuses on communication between IT and business management, rather than on the role of IT professionals inferred by critical survival activities outlined in different organizational theories.Motivated by organizational concerns related to the clarity and articulation of the role of Information Technology professionals in contributing to strategic alignment, our study reviews literature about the role of the information technology professional and the differences according to three organizational theories: Agency theory, Transaction Cost theory and Institutional theory. We then use bibliometrics and content analysis to analyze published research for implicit or explicit skill expectations and contributions to organizational survival and strategic alignment of IT. The goal of our study is to contribute to a better understanding of role conflict, skill expectations, and value of information technology professionals in organizations, and also contribute to a consolidation between information systems research and organizational studies.
A mechanistic model of PCR for accurate quantification of quantitative PCR data.

Background: Quantitative PCR (qPCR) is a workhorse laboratory technique for measuring the concentration of a target DNA sequence with high accuracy over a wide dynamic range. The gold standard method for estimating DNA concentrations via qPCR is quantification cycle (Cq) standard curve quantification, which requires the time- and labor-intensive construction of a Cq standard curve. In theory, the shape of a qPCR data curve can be used to directly quantify DNA concentration by fitting a model to data; however, current empirical model-based quantification methods are not as reliable as Cq standard curve quantification. Principal Findings: We have developed a two-parameter mass action kinetic model of PCR (MAK2) that can be fitted to qPCR data in order to quantify target concentration from a single qPCR assay. To compare the accuracy of MAK2-fitting to other qPCR quantification methods, we have applied quantification methods to qPCR dilution series data generated in three independent laboratories using different target sequences. Quantification accuracy was assessed by analyzing the reliability of concentration predictions for targets at known concentrations. Our results indicate that quantification by MAK2-fitting is as reliable as Cq standard curve quantification for a variety of DNA targets and a wide range of concentrations. Significance: We anticipate that MAK2 quantification will have a profound effect on the way qPCR experiments are designed and analyzed. In particular, MAK2 enables accurate quantification of portable qPCR assays with limited sample throughput, where construction of a standard curve is impractical.
Children with severe speech impairments: caregiver survey of AAC use

To obtain information from caregivers about their children's use of augmentative and alternative communication (AAC) strategies and techniques, caregivers of children with severe speech impairments (SSI) followed at a pediatric rehabilitation center were surveyed (n = 110, 74% response rate). Twenty-eight percent of caregivers reported that their children used nonsymbolic expressions only because their children were “not ready” and/or were “working on skills” for aided AAC use. Caregivers of these children would change the way their children communicate by giving them normal speech, providing more services or by altering their children's AAC use. Thirty-two percent of caregivers reported their children used aided AAC. All of the aided AAC users reportedly used their systems at school and/or work, but less than 66% used their systems at home. Caregivers of these children would change their children's systems by making them more sophisticated, portable, or unbreakable. A small percentage (5%) of caregivers ...
Purification and subunit characterization of the rat liver endocytic hyaluronan receptor.

The endocytic hyaluronan (HA) receptor of liver sinusoidal endothelial cells (LECs) is responsible for the clearance of HA and other glycosaminoglycans from the circulation in mammals. We report here for the first time the purification of this liver HA receptor. Using lectin and immuno-affinity chromatography, two HA receptor species were purified from detergent-solubilized membranes prepared from purified rat LECs. In nonreducing SDS-polyacrylamide gel electrophoresis (PAGE), these two proteins migrated at 175- and ∼300 kDa corresponding to the two species previously identified by photoaffinity labeling of live cells as the HA receptor (Yannariello-Brown, J., Frost, S. J., and Weigel, P. H. (1992) J. Biol. Chem. 267, 20451–20456). These two proteins co-purify in a molar ratio of 2:1 (175:300), and both proteins are active, able to bind HA after SDS-PAGE, electrotransfer, and renaturation. After reduction, the 175-kDa protein migrates as a ∼185-kDa protein and is not able to bind HA. The 300-kDa HA receptor is a complex of three disulfide-bonded subunits that migrate in reducing SDS-PAGE at ∼260, 230, and 97 kDa. These proteins designated, respectively, the α, β, and γ subunits are present in a molar ratio of 1:1:1 and are also unable to bind HA when reduced. The 175-kDa protein and all three subunits of the 300-kDa species containN-linked oligosaccharides, as indicated by increased migration in SDS-PAGE after treatment with N-glycosidase F. Both of the deglycosylated, nonreduced HA receptor proteins still bind HA.
What&#146;s in a Name? A Study of Identifiers

Readers of programs have two main sources of domain information: identifier names and comments. When functions are uncommented, as many are, comprehension is almost exclusively dependent on the identifier names. Assuming that writers of programs want to create quality identifiers (e.g., include relevant domain knowledge) how should they go about it? For example, do the initials of a concept name provide enough information to represent the concept? If not, and a longer identifier is needed, is an abbreviation satisfactory or does the concept need to be captured in an identifier that includes full words? Results from a study designed to investigate these questions are reported. The study involved over 100 programmers who were asked to describe twelve different functions. The functions used three different "levels" of identifiers: single letters, abbreviations, and full words. Responses allow the level of comprehension associated with the different levels to be studied. The functions include standard algorithms studied in computer science courses as well as functions extracted from production code. The results show that full word identifiers lead to the best comprehension; however, in many cases, there is no statistical difference between full words and abbreviations.
1,25-Dihydroxyvitamin D3 Exerts Opposite Effects on the Regulation of Human Embryonic and Nonembryonic Alkaline Phosphatase Isoenzymes*

The regulation of alkaline phosphatase activity by steroid hormones was studied in two human breast cancer cell lines, MDA-MB-157 and BT20. MDA-MB-157 cells were shown to express the alkaline phosphatase isoenzyme produced by normal breast tissue, and the activity of this isoenzyme increased 3-fold after a 72-h treatment of these cells with 10(-7) M 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3], 2-fold after treatment with 10(-6) M hydrocortisone (HC), and 5-fold after treatment with both hormones. BT20 cells did not express the isoenzyme phenotypic to breast, but ectopically expressed the isoenzyme phenotypic to term placenta and other embryonic tissue. Treatment of BT20 cells with 1,25-(OH)2D3 results in a 30% decrease in alkaline phosphatase activity of the embryonic isoenzyme. There was a 2-fold increase in activity after treatment with HC, and enzyme activity was similar to control values after treatment with both hormones. For both cell lines, changes in alkaline phosphatase activity correlated with changes in nanograms of isoenzyme per mg cellular protein, as measured by RIA. Increases in enzyme activity were inhibited when the cells were incubated simultaneously with the steroids and cycloheximide. Studies with receptors in each cell line showed that both cell lines bound 1,25-(OH)2D3 and that a 1,25-(OH)2D3-binding protein with the same mol wt as the D3 receptor was present in both. The BT20 cells also express a larger mol wt protein which binds 1,25-(OH)2D3 but is not as specific for the 1,25-(OH)2D3 isomer. HC receptors were similar in quantity and binding affinity in both cell lines.
Interrater Reliability of the Berg Balance Scale When Used by Clinicians of Various Experience Levels to Assess People With Lower Limb Amputations

Background People with lower limb amputations frequently have impaired balance ability. The Berg Balance Scale (BBS) has excellent psychometric properties for people with neurologic disorders and elderly people dwelling in the community. A Rasch analysis demonstrated the validity of the BBS for people with lower limb amputations of all ability strata, but rater reliability has not been tested. Objective The study objective was to determine the interrater reliability and intrarater reliability of BBS scores and the differences in scores assigned by testers with various levels of experience when assessing people with lower limb amputations. Design This reliability study of video-recorded single-session BBS assessments had a cross-sectional design. Methods From a larger study of people with lower limb amputations, 5 consecutively recruited participants using prostheses were video recorded during an in-person BBS assessment. Sixteen testers independently rated the video-recorded assessments. Testers were 3 physical therapists, 1 occupational therapist, 3 third-year and 4 second-year doctor of physical therapy (DPT) students, and 5 first-year DPT students without clinical training. Rater reliability was calculated using intraclass correlation coefficients (ICC [2,k]). Differences in scores assigned by testers with various levels of experience were determined by use of an analysis of variance with Tukey post hoc tests. Results The average age of the participants was 53.0 years (SD=15.7). Amputations had occurred at the ankle disarticulation, transtibial, and transfemoral levels because of vascular, trauma, and medical etiologies an average of 8.2 years earlier (SD=7.9). Berg Balance Scale scores spanned all ability strata. Interrater reliability (ICC [2,k]=.99) and intrarater reliability of scores determined in person and through video-recorded assessments by the same testers (ICC [2,k]=.99) were excellent. For participants with the lowest levels of ability, licensed professionals assigned lower scores than did DPT students without clinical training. Limitations Intrarater reliability calculations were based on 2 testers. Conclusions Berg Balance Scale scores assigned to people using prostheses by testers with various levels of clinical experience had excellent interrater reliability and intrarater reliability.
Interaction of catenaria anguillulae with romanomermis culicivorax

Abstract The development of Catenaria anguillulae, at 27°C, in live and heat-immobilized Romanomermis culicivorax was studied at the ultrastructural level. C. anguillulae zoospores infected eggs, preparasites, and postparasites. The zoospores attached predominately to the head of preparasites but in postparasites attachment was primarily on the attenuated tail region. Zoospore attachment usually occurred within 4 h but at high zoospore densities attachment occurred within 30 min. Infection hyphae penetrated the cuticle and developed sporangial swellings within the nematode tissues and pseudocoelom. Sporangia produced exit tubes within 48 h. Those regions of the J3 and J4 nematodes infected by C. anguillulae became immobile whereas uninfected regions remained mobile. The J2 infected nematodes usually died within 1–2 days. Tissues adjacent to C. anguillulae hyphae or developing sporangia appeared to be relatively unaffected and ultrastructurally normal. The lack of an apparent host response in the nematode suggested either a lack of hypersensitivity or a long evolutionary host–parasite relationship.
Identification of a Novel Stage of Ribosome/Nascent Chain Association with the Endoplasmic Reticulum Membrane

Protein translocation in the mammalian endoplasmic reticulum (ER) occurs cotranslationally and requires the binding of translationally active ribosomes to components of the ER membrane. Three candidate ribosome receptors, p180, p34, and Sec61p, have been identified in binding studies with inactive ribosomes, suggesting that ribosome binding is mediated through a receptor-ligand interaction. To determine if the binding of nascent chain-bearing ribosomes is regulated in a manner similar to inactive ribosomes, we have investigated the ribosome/nascent chain binding event that accompanies targeting. In agreement with previous reports, indicating that Sec61p displays the majority of the ER ribosome binding activity, we observed that Sec61p is shielded from proteolytic digestion by native, bound ribosomes. The binding of active, nascent chain bearing ribosomes to the ER membrane is, however, insensitive to the ribosome occupancy state of Sec61p. To determine if additional, Sec61p independent, stages of the ribosome binding reaction could be identified, ribosome/nascent chain binding was assayed as a function of RM concentration. At limiting RM concentrations, a protease resistant ribosome-membrane junction was formed, yet the nascent chain was salt extractable and cross-linked to Sec61p with low efficiency. At nonlimiting RM concentrations, bound nascent chains were protease and salt resistant and cross-linked to Sec61p with higher efficiency. On the basis of these and other data, we propose that ribosome binding to the ER membrane is a multi-stage process comprised of an initial, Sec61p independent binding event, which precedes association of the ribosome/nascent chain complex with Sec61p.
Rapid characterization of covalent modifications to rat brain mitochondrial proteins after ex vivo exposure to 4-hydroxy-2-nonenal by liquid chromatography-tandem mass spectrometry using data-dependent and neutral loss-driven MS3 acquisition.

The modification of mitochondrial proteins enriched from rat forebrain by the major lipid peroxidation product 4-hydroxy-2-nonenal (HNE) was investigated using high performance liquid chromatography (HPLC) and tandem mass spectrometry. Subcellular fractionation in conjunction with a 'shotgun-based' approach that involved both conventional data-dependent and neutral loss (NL)-driven MS 3 data acquisition on a hybrid linear ion trap-Fourier transform ion cyclotron resonance mass spectrometer (LTQ-FT) was utilized. Using a relatively rapid linear HPLC gradient (1 h) for complex mixture analysis, 24 sites of HNE modification on 15 unique proteins were identified which corresponded exclusively to Michael adduct formation on histidine residues. Since a number of HNE-modified peptides produced a predominant HNE NL fragment-ion signal upon collision-induced dissociation (CID), NL-driven MS 3 data-dependent acquisition was a valuable method to enhance fragmentation information for these particular modified peptides. Of the 24 HNE modification sites identified, approximately 25% were determined from the MS 3 spectra alone. We envision the reported methodology as an efficient screening approach for HNE modification site selectivity that could ultimately provide a foundation for the development of targeted schemes for the characterization of in vivo HNE-protein adducts.
Permeability of solutes through hydrated polymer membranes. Part III. Theoretical background for the selectivity of dialysis membranes

The diffusional transport of aqueous solutes through water swollen polymer membranes is examined by the concept of the free volume of the water-polymer systems, Vf,13. The relative diffusivity (D in membrane/D in water) can be expressed by the product of the probability factor of finding holes of equal or larger cross section, q, than the cross section of solute, q2, (sieve mechanism) and the free volume factor. An analysis of experimental data indicates that within the range of solute size investigated (up to albumin) the sieve mechanism is not yet playing a role in homogeneous cellulosic membranes. The main reduction of permeability of larger solutes is caused by the free volume term which is an exponential function of the negative cross section of the solute, q2, exp (–Bq2/Vf,13). In porous membranes, however, the sieve mechanism alone is responsible for the selectivity. Der Diffusionstransport des Gelosten durch in Wasser gequollene Membranen wurde an Hand des Modells des freien Volumens (Vf,13) des Polymer/Wasser-Systems untersucht. Die relative Diffusionsfahigkeit (D2,13 in der Membran/D2,1 im Wasser) kann dargestellt werden als das Produkt aus dem Wahrscheinlichkeitsfaktor zum Auffinden von Hohlraumen mit gleichem oder groserem Querschnitt als das Geloste (Siebmechanismus) und dem Faktor des freien Volumens. Die vorhandenen experimentelle Daten fuhren zu der Schlusfolgerung, das der Siebmechanismus in homogenen Cellulosemembranen bis zu der Molekulgrose von Albumin keine beachtliche Rolle spielt. Entscheidend fur die Verringerung der Permeabilitat fur grosere Molekule des Gelosten ist der Faktor mit dem freien Volumen, exp (–Bq2/Vf,13), der den Querschnitt des Gelosten (q2) als negatives Argument in der Exponentialfunktion enthalt. In porosen Membranen ist jedoch der Siebmechanismus allein fur die Selektivitat verantwortlich.
Local wall thickness in finite element models improves prediction of abdominal aortic aneurysm growth.

Objective Growing evidence suggests that peak wall stress (PWS) derived from finite element analysis (FEA) of abdominal aortic aneurysms (AAAs) predicts clinical outcomes better than diameter alone. Prior models assume uniform wall thickness (UWT). We hypothesize that the inclusion of locally variable wall thickness (VWT) into FEA of AAAs will improve its ability to predict clinical outcomes. Methods Patients with AAAs (n = 26) undergoing radiologic surveillance were identified. Custom MATLAB algorithms generated UWT and VWT aortic geometries from computed tomography angiography images, which were subsequently loaded with systolic blood pressure using FEA. PWS and aneurysm expansion (as a proxy for rupture risk and the need for repair) were examined. Results The average radiologic follow-up time was 22.0 ± 13.6 months and the average aneurysm expansion rate was 2.8 ± 1.7 mm/y. PWS in VWT models significantly differed from PWS in UWT models (238 ± 68 vs 212 ± 73 kPa; P = .025). In our sample, initial aortic diameter was not found to be correlated with aneurysm expansion ( r = 0.26; P = .19). A stronger correlation was found between aneurysm expansion and PWS derived from VWT models compared with PWS from UWT models ( r = 0.86 vs r = 0.58; P = .032 by Fisher r to Z transformation). Conclusions The inclusion of locally VWT significantly improved the correlation between PWS and aneurysm expansion. Aortic wall thickness should be incorporated into future FEA models to accurately predict clinical outcomes.