cssi/SciSciGPT-SciSciNet huggingface dataset:
Hydrodynamic effects of compliance mismatch in stented arteries.

Cardiovascular diseases are the number one cause of death in the world, making the understanding of hemodynamics and development of treatment options imperative. The most common modality for treatment of occlusive coronary artery diseases is the use of stents. Stent design profoundly influences the postprocedural hemodynamic and solid mechanical environment of the stented artery. However, despite their wide acceptance, the incidence of stent late restenosis is still high (Zwart et al., 2010, "Coronary Stent Thrombosis in the Current Era: Challenges and Opportunities for Treatment, " Current Treatment Options in Cardiovascular Medicine, 12(1), pp. 46―57), and it is most prevailing at the proximal and distal ends of the stent. In this work, we focus our investigation on the localized hemodynamic effects of compliance mismatch due to the presence of a stent in an artery. The compliance mismatch in a stented artery is maximized at the proximal and distal ends of the stent. Hence, it is our objective to understand and reveal the mechanism by which changes in compliance contribute to the generation of nonphysiological wall shear stress (WSS). Such adverse hemodynamic conditions could have an effect on the onset of restenosis. Three-dimensional, spatiotemporally resolved computational fluid dynamics simulations of pulsatile flow with fluid-structure interaction were carried out for a simplified coronary artery with physiologically relevant flow parameters. A model with uniform elastic modulus is used as the baseline control case. In order to study the effect of compliance variation on local hemodynamics, this baseline model is compared with models where the elastic modulus was increased by two-, five-, and tenfold in the middle of the vessel. The simulations provided detailed information regarding the recirculation zone dynamics formed during flow reversals. The results suggest that discontinuities in compliance cause critical changes in local hemodynamics, namely altering the local pressure and velocity gradients. The change in pressure gradient at the discontinuity was as high as 90%. The corresponding changes in WSS and oscillatory shear index calculated were 9% and 15%, respectively. We demonstrate that these changes are attributed to the physical mechanism associating the pressure gradient discontinuities to the production of vorticity (vorticity flux) due to the presence of the stent. The pressure gradient discontinuities and augmented vorticity flux are affecting the wall shear stresses. As a result, this work reveals how compliance variations act to modify the near wall hemodynamics of stented arteries.
Focused JPEG encoding based upon automatic preidentified regions of interest

We have developed a focused-procedure based upon a collection of image processing algorithms that serve to identify regions-of-interest (ROIs), over a digital image. To loci of these ROIs are quantitatively compared with ROIs identified by human eye fixations or glimpses while subjects were looking at the same digital images. The focused- procedure is applied to adjust and adapt the compression ratio over a digital image: - high resolution and poor compression for ROIs; low resolution and strong compression for the major expanse of the entire image. In this way, an overall high compression ratio can be achieved, while at the same time preserving, important visual information within particularly relevant regions of the image. We have bundled the focused-procedures with JPEG, so that the JPEG version allows the result of the compression to be formatted into a file compatible for standard JPEG decoding. Thus, once the image has been compressed, it can be read without difficulty.
Pharyngeal dilation in cricopharyngeus muscle dysfunction and Zenker diverticulum.

Objectives/Hypothesis: Prolonged obstruction at the level of the lower esophageal sphincter is associated with a dilated, poorly contractile esophagus. The association between prolonged obstruction at the level of the upper esophageal sphincter (UES) and dilation and diminished contractility of the pharynx is uncertain. The purpose of this investigation was to evaluate the association between prolonged obstruction at the level of the UES and dilation and diminished contractility of the pharynx. Study Design: Case-control study. Methods: The fluoroscopic swallow studies of all persons with cricopharyngeus muscle dysfunction (CPD) diagnosed between January 1, 2006 and December 31, 2008 were retrospectively reviewed from a clinical database. Three categories of CPD were defined: nonobstructing cricopharyngeal bars (CPBs), obstructing CPBs, and Zenker diverticulum (ZD). The primary outcome measure was the pharyngeal constriction ratio (PCR), a surrogate measure of pharyngeal strength on fluoroscopy. Secondary outcome measures included pharyngeal area in the lateral fluoroscopic view and UES opening. The outcome measures were compared between groups and to a cohort of nondysphagic age- and gender-matched controls with the analysis of variance. Results: A total of 100 fluoroscopic swallow studies were evaluated. The mean age (±standard deviation) of the cohort was 70 years (±10 years). Thirty-six percent were female. The mean PCR progressively increased, indicating diminishing pharyngeal strength, from the normal (0.08), to the nonobstructing CPB (0.13), to the obstructing CPB (0.22), to the ZD group (0.28) (P < .001 with trend for linearity). There was a linear increase in pharyngeal area from the normal (8.75 cm2) to the nonobstructing CPB (10.00 cm2), to the obstructing CPB (10.46 cm2), to the ZD group (11.82 cm2) (P < .01 with trend for linearity). Conclusions: The data suggest that there is an association between cricopharyngeus muscle dysfunction and progressive dilation and weakness of the pharynx. Laryngoscope, 2010
Reactivity of the alkaline phosphatases of bovine milk and intestinal mucosa with the substrates phenyl phosphate and o-carboxyphenyl phosphate.

Abstract Bovine intestinal mucosa alkaline phosphatase reacts equally with the substrates phenyl phosphate and o -carboxyphenyl phosphate. Milk alkaline phosphatase, on the other hand, at a concentration of the substrates of about 8 × 10 −5 moles/l., is 1 3 to 1 4 reactive with the o -carboxyphenyl phosphate as with phenyl phosphate. Analyses of these reactions with a range of substrate concentrations showed that the difference in reactivity is due to a difference in enzyme-substrate dissociation constants, K m . The p K m values for the mucosa phosphatase with both substrates at pH 9.7 is 3.7; with the milk phosphatase and phenyl phosphate the p K m value is 4.6, whereas with o -carboxyphenyl phosphate the value is 2.8. The K m values were also determined for a range of pH values. The difference noted above persisted throughout. K m values obtained with the milk phosphatase in a lipide-containing complex were identical with values obtained with the phosphatase after dissociating with n -butyl alcohol.
How are hypertensive children evaluated and managed? A survey of North American pediatric nephrologists

To assess how children with hypertension are currently evaluated and managed, we surveyed 438 North American pediatric nephrologists on how they measure blood pressure (BP), BP goals used in pharmacologically treated patients, and antihypertensive drug choices. 190 replies were received (43% response rate), and 185 were analyzable. Oscillometric and aneroid sphygmomanometers were the most commonly used devices for office BP measurement (74.8% of respondents). Ambulatory blood pressure monitoring was used by 63% of respondents. Goal BP in pharmacologically treated patients was set at the 95th percentile by 39% of respondents, and at the 90th percentile by 59%. Only 37% used a different goal BP in children with hypertension and renal disease; of these, 85% used a lower goal and 15% a higher goal. For hypertensive children with diabetes, 47% used a different goal; 99% lower and 1% higher. Whereas angiotensin-converting enzyme inhibitors (ACEI) and calcium-channel blockers (CCB) were chosen by similar proportions of respondents as initial agents for treatment of primary hypertension, most (84%) chose ACEI as their initial agent for hypertension in children with renal disease.
Predicting success for baccalaureate graduates on the NCLEX-RN.

Abstract The purpose of this retrospective study was to identify predictors of success for baccalaureate nursing graduates on the National Council Licensure Examination-Registered Nurse (NCLEX-RN). Subjects (505) were graduates of a baccalaureate nursing program in the southeastern United States from 1993 to 1998. The outcome variable was pass/fail on the NCLEX-RN on the first attempt. Predictor variables included type of student (freshman admission, transfer, second degree), age at the time of licensing examination, gender, performance on selected prenursing courses, performance in all junior and senior nursing courses, cumulative grade point average (GPA) at graduation and the Mosby AssessTest score. Results showed a significant relationship between number of Cs, Ds, and Fs in nursing courses and NCLEX-RN results. Students who passed the NCLEX-RN had significantly higher average GPAs, made fewer grades of C or below, and scored higher on the Mosby AssessTest than students who failed. Nontraditional college-age students tended to have a higher passing rate than did traditional age students. A logistic regression model was developed that correctly predicted 76 per cent of the students who failed based on the information available by the end of the end of the first semester of the senior year. J Prof Nurs 17:121-127, 2001. Copyright © 2001 by W.B. Saunders Company
Pneumatic paracorporeal ventricular assist device in infants and children: initial Stanford experience.

Background Mechanical circulatory support with the Berlin Heart EXCOR pediatric ventricular assist device (VAD) has been used successfully in Europe for children with cardiac failure. Eighty-seven devices have been placed in North America through February 2007. We describe our single-center experience in 8 children. Methods Eight children (ages 4 to 55 months), with median weight of 9.6 kg and body surface area of 0.48 m 2 , received the Berlin Heart VAD as a bridge to transplantation. All patients were in cardiogenic shock requiring multiple inotropes. Primary diagnoses were idiopathic dilated cardiomyopathy ( n = 4), congenital heart disease ( n = 3) and restrictive cardiomyopathy ( n = 1). After device insertion, all patients were treated with an anti-coagulant (heparin or coumadin) and one or more platelet inhibitors (aspirin with clopidogrel or dipyridamole). Results Five patients received support with a left ventricular assist device (LVAD) and 3 with a biventricular device (BiVAD). Duration of support ranged from 2 to 234 days (median 57 days). Five patients (63%) were successfully bridged to transplantation; of these, 4 were discharged home and 1 died from early graft failure. Five patients developed post-operative neurologic events. Of these 5 events, 4 could be explained by embolism or hemorrhage. Device exchange was performed in 4 patients in the intensive care unit. Conclusions In selected children, the Berlin Heart VAD can be used as a bridge to transplantation. In contrast to the published European experience, neurologic events occur frequently. Anti-coagulation and platelet inhibition strategies continue to evolve. Device exchange is technically feasible at the bedside and should be considered at the earliest visualization of thrombus formation.
Status of the Journal of Dairy Science for 1973 and Editorial Comments

Transition of editors from experienced to inexperienced was the significant change of Volurne 56. The training, advice, and help graciously given by Editor-emeritus E. O. Herreid reduced the visibility of change. The constant most helpful in stabilizing the transition w a s the expertise and guidance of Executive Secretary C. J. Cruse. We recognize also the support of the Journal Management Committee, the Board of Directors, the Editorial Board and other reviewers, and authors offering their papers (at least their patience and understanding). Volume 56 was smaller than 55 and 54. The distribution of contents is in Table 1. The number of manuscripts submitted in 1973 is about 80 less than offered in 1972. Turbulences for preparation of Volume 56 were few but troublesome. I regret J. E. Kinsella's need to resign as Associate Editor and the loss of his helpful skill. Journal Management is seeking a replacement. Indexing could have been a problem had not Herreid solved that by preparing the subject index this year. Quality of reproduction of some figures in reprints has been bothersome. Papers from symposia of the annual meeting have been frustratingly slow in preparation. Most bothersome of all has been the enormous waste for all in unconcerned preparation of reports by authors. Some papers have not been proofread, let alone the unreasonable frequency of those which have not been reviewed or edited locally even by a joint author. Papers with defects sufficient to require review :after adjustment or revision are in review and revision more than twice as long as those accepted on first review. For example, papers from receipt at ADSA to approval for press can complete in less than 30 days; many range from 40 to 60 days; they average about 90 days on single review but nearly 200 days with repeat review. Rare is the reviewer who eagerly can anticipate inspecting a paper which promises pure drudgery. Attention to Instructions for Authors and review by colleagues could expedite greatly speed and effectiveness of reporting. Abstracts for national and sectional meetings continue to plague editors with their need for extensive editing in restricted time. Policy of the Journal of Dairy Science is not to abbreviate in title and abstract except units of measure with digits. This requirement is now an instruction to authors. Occasionally to glance through the CBE Style Manual reminds an author of deviations from effective reporting. Accomplishments of Amy Garant, Technical Editor, have been indispensable to publication of Volume 56. Readers, authors, and editors of the Journal appreciate her assistance and that of members of the Editorial Board in their needed efforts toward a publication of quality. The task has been too large for them alone, and I acknowledge with gratitude the generous help of these scientists.
Cardiac change scale: A brief, self-report research measure

The purpose of this study was to develop and evaluate a brief, self-report measure of the degree of perceived change resulting from cardiac illness. Life change has been widely recognized as stressful, but it is usually assessed with generic checklists of events which have been found wanting in terms of reliability and validity. The proposed measure was designed to assess life change in factors commonly reported to be important in recovery from cardiac illness. The Cardiac Change Scale was found to have very good internal consistency and acceptable test-retest reliability. The construct and criterion validity of the Cardiac Change Scale were supported.
Electrophoric release tags: Ultrasensitive molecular labels providing multiplicity

Abstract Electrophoric release tags are a new class of analytical reagents which function as molecular labels. These tags can be more sensitive than radioisotopes and their potential for multiplicity allows release-tagged reagents to be used as 'teams' in chemical analysis. Monoclonal antibodies, nucleic acid probes, receptor ligands and enzyme substrates may all benefit from this approach.
Environmental Factors Influencing Gene Transfer Agent (GTA) Mediated Transduction in the Subtropical Ocean

Microbial genomic sequence analyses have indicated widespread horizontal gene transfer (HGT). However, an adequate mechanism accounting for the ubiquity of HGT has been lacking. Recently, high frequencies of interspecific gene transfer have been documented, catalyzed by Gene Transfer Agents (GTAs) of marine α-Proteobacteria. It has been proposed that the presence of bacterial genes in highly purified viral metagenomes may be due to GTAs. However, factors influencing GTA-mediated gene transfer in the environment have not yet been determined. Several genomically sequenced strains containing complete GTA sequences similar to Rhodobacter capsulatus (RcGTA, type strain) were screened to ascertain if they produced putative GTAs, and at what abundance. Five of nine marine strains screened to date spontaneously produced virus-like particles (VLP's) in stationary phase. Three of these strains have demonstrated gene transfer activity, two of which were documented by this lab. These two strains Roseovarius nubinhibens ISM and Nitratireductor 44B9s, were utilized to produce GTAs designated RnGTA and NrGTA and gene transfer activity was verified in culture. Cell-free preparations of purified RnGTA and NrGTA particles from marked donor strains were incubated with natural microbial assemblages to determine the level of GTA-mediated gene transfer. In conjunction, several ambient environmental parameters were measured including lysogeny indicated by prophage induction. GTA production in culture systems indicated that approximately half of the strains produced GTA-like particles and maximal GTA counts ranged from 10–30% of host abundance. Modeling of GTA-mediated gene transfer frequencies in natural samples, along with other measured environmental variables, indicated a strong relationship between GTA mediated gene transfer and the combined factors of salinity, multiplicity of infection (MOI) and ambient bacterial abundance. These results indicate that GTA-mediated HGT in the marine environment with the strains examined is favored during times of elevated bacterial and GTA abundance as well as in areas of higher salinity.
Deriving theoretical boundaries to address scale dependencies of triangle models for evapotranspiration estimation

[1] Satellite-based triangle models for evapotranspiration estimation are unique in interpreting the relationship between the normalized difference vegetation index (NDVI)/factional vegetation cover (fc) and surface radiative temperature (Trad) across large heterogeneous areas. However, output and performance of triangle models may depend on the size of the domain being studied and resolution of the satellite images being used. The objective of this study was to assess domain and resolution dependencies of triangle models using progressively larger domains and Landsat Thematic Mapper/Enhanced Thematic Mapper Plus and Moderate Resolution Imaging Spectroradiometer sensors at the Soil Moisture-Atmosphere Coupling Experiment site in central Iowa on days of year 174 and 182 in 2002. Results show domain and resolution dependencies of the triangle models with large uncertainties in evaporative fraction (EF) estimates in terms of a mean absolute percentage difference (MAPD) up to ∼50%. A trapezoid model which requires derivation of theoretical limiting edges of the NDVI-Trad space is proposed to constrain domain and resolution dependencies of triangle models. The theoretical warm edge can be derived by solving for temperatures of the driest bare surface and the fully vegetated surface with the largest water stress implicit in both radiation budget and energy balance equations. Areal average air temperature can be taken as the theoretical cold edge. The triangle model appears to perform well across large areas (∼104 km2) but fails to predict EF over small areas (∼102 km2). The trapezoid model can effectively reduce domain and resolution dependencies and constrain errors of the EF estimates with an MAPD of ∼10%.
Optical receiver design for high optical return loss

A new fiber pigtailed optical receiver design using a single gradient-index rod lens with a beveled exit face achieved a broadband optical return loss of >65 dB, which was limited by the diffuse reflection from the photodetector front surface. By contrast the optical return loss for a receiver with an unbeveled lens exit face and an on-axis optical path was limited to a smaller value by the specular reflection from the lens exit face.
The 1976 outbreak of Hog Cholera in New Jersey: An application of geology to a biological emergency

Hog cholera is a highly contagious virus disease of swine. Since 1962, a Hog Cholera Eradication Program has replaced vaccination as the control mechanism in the U.S. Because the cholera agent requires a live host to thrive, quarantine and herd depopulation are ordered at every U.S. outbreak. The results have been positive and dramatic.
Reforming indicated type theories

There is some intuitive plausibility to the idea that composers create musical works by indicating sonic types in a historical context. But the idea is technically indefensible as it stands, requiring a thorough representational reform that also eliminates the type-theoretic commitments of current versions. On the reformed account, musical 'indication' is an operation of high-level representational interpretation of concrete sounds, that can both explain the creativity of composers, and the often successful interpretations of their listeners. This approach also bypasses contentious issues regarding the status of both indicated and 'initiated' types, as extensively discussed in the BJA.
A group additivity approach for the prediction of wavelength-dependent absorption cross-sections

Abstract Photolysis is an important loss process of carbonyl, peroxy, and nitrate species in the atmosphere. In general, photolysis rate coefficients depend on the intensity of radiation, wavelength, temperature, and the specific molecule reacting. One key source of differences in rate coefficients between different molecules is the absorption cross-section, σ, which is specific to the reactive molecule under consideration. In order to calculate rate coefficients for photolytic processes, a value of σ must be specified or estimated. To this end, a group additivity approach was developed that can be used to estimate the values of σ of species that photolyze primarily in the 290– 370 nm wavelength region. We demonstrate that this approach can be used to predict accurately unknown values of σ of species for which experimental data are not available.
Development of quantitative structure–property relationships for predictive modeling and design of energetic materials

Abstract A quantitative structure–property relationship (QSPR) based on the AM1 semiempirical quantum mechanical method was derived using the program, CODESSA, to describe published drop height impact sensitivities for 227 nitroorganic compounds. An eight-descriptor correlation equation having R 2 = 0.8141 was obtained through a robust least median squares regression. The resulting model is the most comprehensive and systematic quantum mechanically derived QSPR for energetic materials of those that have been published. The predictive capability of the model is also presented and discussed.
Carbon, climate, and economic breakeven times for biofuel from woody biomass from managed forests

Woody biomass harvested from old-growth forests results in a significant “carbon debt” when used as a feedstock for transportation fuel. This is because previously stored forest carbon is released to the atmosphere as CO2. The debt is eventually repaid provided that the life cycle CO2 emissions of the biofuel are lower than the conventional fuel that is displaced. Managed forests are an alternative to old-growth forests with the potential to reduce the carbon debt associated with woody biomass-derived fuels. This work is the first to quantify the carbon debt incurred by transportation biofuels derived from woody biomass from managed forests. The breakeven time of this carbon debt is computed along with breakeven times for radiative forcing, temperature change, and economic damages. In the case of biofuel production for 30 years, we find that breakeven times for carbon, radiative forcing, and temperature change are 59, 42, and 48 years, respectively. If cumulative economic damages are computed for discount rates of 1–2%, the breakeven time is greater than 100 years, while damages never break even at discount rates above 2%. Breakeven times decrease if the prevailing harvest cycle is left unchanged, but increase if biofuel production is sustained indefinitely.
Cue Effectiveness in Communicatively Efficient Discourse Production

Recent years have seen a surge in accounts motivated by information theory that consider language production to be partially driven by a preference for communicative efficiency. Evidence from discourse production (i.e., production beyond the sentence level) has been argued to suggest that speakers distribute information across discourse so as to hold the conditional per-word entropy associated with each word constant, which would facilitate efficient information transfer (Genzel & Charniak, 2002). This hypothesis implies that the conditional (contextualized) probabilities of linguistic units affect speakers’ preferences during production. Here, we extend this work in two ways. First, we explore how preceding cues are integrated into contextualized probabilities, a question which so far has received little to no attention. Specifically, we investigate how a cue's maximal informativity about upcoming words (the cue's effectiveness) decays as a function of the cue's recency. Based on properties of linguistic discourses as well as properties of human memory, we analytically derive a model of cue effectiveness decay and evaluate it against cross-linguistic data from 12 languages. Second, we relate the information theoretic accounts of discourse production to well-established mechanistic (activation-based) accounts: We relate contextualized probability distributions over words to their relative activation in a lexical network given preceding discourse.
The Interplay Between Biomechanical and Biochemical Factors Regulates Lumen Formation and Navigation of Endothelial Cell Sprouts

Angiogenesis is the process of forming new blood vessels that originate from pre-existing vessels. In early angiogenesis stages, endothelial cells (ECs) migrate from the lumen of developed blood vessels into the surrounding extracellular matrix (ECM). Through the coordinated actions of migration and proliferation, these ECs organize into tubular capillary-like structures called sprouts. In this study, 3D EC sprout formation was examined using a microfluidic device that enabled the separate and simultaneous tuning of biomechanical and biochemical stimuli (Fig. 1). While previous investigations have been performed on each of these factors individually1, 2, more recent studies have identified a critical interplay between the simultaneous effects of these two factors3. For example, we previously studied 2D EC chemotaxis in response to vascular endothelial growth factor (VEGF) gradients in the absence of biomechanical stimulation.4 In developing a model that enables precise specification of biochemical and biomechanical cues, we utilized a protocol that enables ECs to undergo a transition from the 2D to 3D culture environment mimicking angiogenic sprouting. Here we quantified the relative importance and combined consequences of discrete changes in matrix density, growth factor concentration, and growth factor gradient steepness during the stages of early sprout initiation, sprout elongation, sprout navigation, and lumen formation.© 2010 ASME
Paths to Negotiation Success

This article presents a multi-variable model of the negotiation process and tests it via a series of meta-analyses and follow-up path analyses. Negotiator goals, relationships, expectations, and behavior are tested as predictors of (a) the profit-or-loss outcome of the negotiation, (b) the negotiator’s perceptions of the other party, and (c) the negotiator’s satisfaction with the negotiation. A path model was tested based on separate meta-analyses to create the correlation table of the seven variables. The findings demonstrate that to be successful, negotiations should focus on goals and cooperation within the negotiation. High goals and positive relationships started negotiators on the path to successful outcomes.
Protein dynamics and function: Making new strides with an old warhorse, the alkaline conformational transition of cytochrome c

Abstract Protein dynamics is intimately linked to function. In metalloproteins, dynamics are often coupled to redox activity, ligand binding and enzyme function. We provide a concise overview of the field and then focus on the use of the alkaline conformer of cytochrome c as a model system to probe the factors that control the conformational dynamics of proteins in general and metalloproteins in particular. We consider the effects of ligands on metal-mediated dynamics, the interplay between intrinsic metal-ligand dynamics and barriers imposed by the protein scaffold itself, and the effects of local and overall protein stability on dynamics. Discussed within are the collected results from equilibrium thermodynamic methods, pH jump kinetics and conformationally gated redox reactions between small inorganic reagents and metalloproteins used as a means to probe conformational switching in metalloproteins.
Insider trading and risk aversion

Abstract This paper is a continuous time version of Holden and Subrahmanyam (Economics Letters 44 (1994) 181). The paper extends Kyle (Econometrica 53 (1985) 1315) by introducing risk aversion on the side of the monopolist informed trader and allows for the liquidity traders instantaneous demand to depend on cost of trading, as well as on the risk of the stock. The main result of the paper is that, in equilibrium, the price pressure decreases with time regardless of the elasticity of the liquidity demand function.
Analytical reactions of isomeric methoxycycloheptatrienes

Abstract Methods for distinguishing among the isomeric 1-, 3- and 7-methoxycycloheptatrienes are reported. Treatment with anisaldehyde in strong perchloric acid produced a blue solution for the first two compounds only (with detection limits of the order of 2 μg), while irradiation ar 256 nm prior to treatment gave magenta solutions for the first and third compounds only. Absorbance was linear with respect to concentration, at least in the range 0.5–8 μg m−1. Both the 1- and 3-isomers were oxidized by cerium(IV) to tropylium salts while the 7-isomer was resistant to attack. Similarly, the 7-isomer did not react with sodium tetrachloropalladate(II) on filter paper while the other two compounds gave black spots.
Isolation and structural organization of human mitotic chromosomes

New methods are presented for the bulk isolation of metaphase chromosomes from HeLa cells, and an electron microscopic study of thin sections of these chromosomes is presented. The techniques for chromosome isolation were developed to utilize solution conditions that are as mild as possible, so that further biochemical and structural studies can be directly related to the in situ state of chromosomes. — Electron micrographs of thin sections of isolated HeLa metaphase chromosomes reveal the general organization of the nucleosome-containing fibers. Chromosomes in isolation buffer show a dense, relatively uniform distribution of material across the chromatids. Swollen chromosomes reveal the primary mode of organization of the fibers to be a radial distribution from the central axes of the chromatids. A significant proportion of the fibers could also be oriented longitudinally.
Reintroduction of Oxaliplatin: A Viable Approach to the Long-Term Management of Metastatic Colorectal Cancer

Oxaliplatin-based chemotherapy is an effective first-line treatment option for patients with metastatic colorectal cancer (mCRC), which, in combination with targeted therapies and a sequential treatment approach using all active agents, has extended median overall survival to 2 years and beyond. Prolonged survival brings into focus the burden of treatment, in terms of associated toxicities and quality of life, and attention is now being paid to lowering the toxicity burden for patients receiving chemotherapy for mCRC without compromising efficacy. The use of oxaliplatin can lead to the development of sensory neuropathy, which commonly limits the dose and/or duration of treatment that can be administered. Temporary withdrawal of oxaliplatin (treatment holidays) has been shown to be an effective strategy for the management of this adverse effect. Data from randomized controlled trials indicate that a formalized stop-and-go approach to the delivery of oxaliplatin does not compromise efficacy, and indeed for some patients may prove beneficial by allowing them to continue treatment for longer periods. This paper presents a critical review of the evidence to support the utility of treatment interruption and reintroduction of oxaliplatin for the long-term management of mCRC.
Photoacoustic imaging: high-resolution optical imaging beyond the quasi-ballistic regime

Photoacoustic imaging can penetrate beyond ~1 mm into scattering biological tissues. It is a hybrid functional imaging technology that combines high ultrasonic resolution and strong optical contrast in a single modality.
Errors in centering of array data can induce biases in correlation estimates

For a general class of microarray data sets, the sample specific centering errors can constitute correlated measurement errors. These errors are perfectly correlated within samples in the sense that all spot assays within a given sample are centered with the same error. Under certain biological conditions, the centering errors can also be correlated to a specific subset of spot assays. In contrast to the within-sample correlated errors, the correlation of centering errors to select spot assays can be thought of as an across-sample correlation (e.g., for the cases presented in this manuscript, the spot assay by centering error correlation only exists if the skew of the distribution varies across samples with the variation dependent on a subset of spot assays). We demonstrate that the perfect within sample correlation of the centering errors induces a positive bias in spot assay by spot assay correlation estimates while negative across-sample correlations can induce a negative bias in said estimates. We provide analyses of a real and simulated data set and demonstrate that, under realistic conditions, the centering errors can induce biases in spot assay by spot assay correlation estimates while not significantly affecting permutation-based thresholds for significance; a combination which can lead to a breakdown in error control.
Disturbing the solar system: Impacts, close encounters, and coming attractions by Alan E. Rubin

Book Review: Disturbing the Solar System, Alan E. Rubin. Princeton University Press, Princeton, New Jersey, USA (2002).
PADS: enhancing gaming experience using profile-based adaptive difficulty system

In this paper, we present a novel methodology to improve gaming experiences by automatically adjusting the game difficulty throughout the game play using a Profile-based Adaptive Difficulty System (PADS). We utilize a player's gaming experience and objective to create a player profile. Utilizing this profile and a performance-based algorithm, the PADS customizes the game's difficulty levels to accommodate each individual. Our experimental results successfully demonstrate improvements in both perceptual and actual gaming experiences. With our approach, traditional program-centered video games can be transformed to provide individualized, player-centered gaming experiences.
An empirical analysis of the unit labor cost-product price relation in the U.S. economy

This article tests for cointegration between unit labor costs and the level of product prices in four sectors of the U.S. economy: the aggregate business sector, the nonfinancial corporate sector, durable manufacturing, and nondurable manufacturing. A finding of cointegration for most specifications supports the existence of long-run labor market equilibrium for producers and suggests estimation of error-correction models to examine the dynamic relationships. In every sector except nondurable manufacturing, error-correction model estimates indicate there is a mutual feedback relationship between unit labor costs and prices. Controlling for deviations from full employment, oil price shocks, and the Nixon wage and price controls, the results also provide evidence of significant nominal wage indexation in U.S. labor markets. Throughout the economy there appears to exist both effective neoclassical wage and price adjustment mechanisms to maintain labor market equilibrium and short-run rigidities which may contribute to deviations from full employment outcomes.
Safety, tolerability, and pharmacokinetics of idebenone in a dose-escalation trial in patients with Friedreich's ataxia

Friedreich's ataxia is a progressive neurodegenerative disorder caused by a GAA trinucleotide expansion within the fraxatin gene. This mutation results in a loss of the frataxin protein within mitochondria leading to reduced activity of key enzymes, excess production of free radicals, and defective oxidative phosphorylation. Recent studies suggest that the antioxidant, idebenone, may prevent disease progression and greater efficacy may be seen with higher doses. In order to explore the full dose range, 81 patients divided evenly among adults, adolescents, and children participated in an unblinded, 1 day dose-escalation trial of oral idebeonone divided TID. No dose limiting toxicity was observed, and the maximum allowed dose of 75 mg/kg was achieved in all cohorts. Analysis of serum levels of total idebenone revealed a large variation in absorption of the drug. This variation precluded complete analysis of plasma concentration obtained during repetitive dosing; however, the terminal half-life following the last dose was consistent across the dose levels, indicating dose proportionality. A follow-up study in 15 patients revealed that a dose of 60 mg/kg/day was safe and well tolerated for 1 month. These findings indicate that higher doses of this drug should be explored for efficacy in Friedreich's ataxia and other diseases associated with oxidative stress. Clinical Pharmacology & Therapeutics (2005) 77, P68–P68; doi: 10.1016/j.clpt.2004.12.150
Amperometric operation of porous flow-through electrodes at very low conversion efficiencies in flow stream detectors

The limiting current equation for a porous flow-through electrode operated amperometrically at low conversion efficiencies can be expressed in the same general format as that for amperometric detectors of other types. The equation shows that a critical dimension for the porous electrode is the pore diameter, the limiting current being inversely proportional to the two-thirds, power of the pore radius. Experimental verification was obtained using reticulated vitreous carbon (RVC) electrodes.
Blood Neutrophil-to-Lymphocyte Ratio is Prognostic in Gastrointestinal Stromal Tumor

Background The immune system has been shown to play an important role in gastrointestinal stromal tumor (GIST). The neutrophil-to-lymphocyte ratio (NLR) in blood is an easily assessable parameter of systemic inflammatory response. The aim of this study was to determine whether the NLR is prognostic in GIST.
Caveats of Course Coordination

The Accreditation Board for Engineering and Technology (ABET) accredits eight engineering departments at the Colorado School of Mines (CSM). As a support department, the Mathematical and Computer Sciences Department (MCS) has established an assessment system that relies heavily on coordinated courses. This paper examines the impact of collaboration on student pass rates in the coordinated courses. A comparison is made between the pass rates in the coordinated courses to the pass rates in the non-coordinated courses at the same academic levels. The information gathered from this investigation begins to answer the important question as to whether coordination is an effective mechanism for ensuring quality across multiple course sections. An analysis is also presented on the engineering curriculum at CSM to determine the impact that failure within a given courses has on students' progression toward an engineering degree.
Commentary to ''Outcome of severe hypospadias repair using three different techniques''

What defines ‘severe’ hypospadias? The authors describe those having ‘proximal division of the corpus spongiosum’, but others might consider penoscrotal to perineal hypospadias the ‘severe’ cases, while another definition in this era of urethral plate-based urethroplasty might be those whose ventral curvature leads to plate transection. Less ambiguous terms are needed for surgeons to clearly communicate their experiences to each other. Consider the illustrations: few would disagree that the perineal hypospadias in Fig. 1 qualifies as a ‘severe’ case, but Fig. 2 appears to show a distal shaft meatus few would classify ‘severe’. Discussion regarding ‘hypoplastic tissues’ and ‘quality of the urethral plate’ adds more subjective terms likely to be interpreted by readers differently. The problem is not unique to this report, nor to these authors, but for hypospadiology to progress we all must describe our patients and interventions as clearly as possible so that other surgeons can understand what is being done to whom. Proximal shaft to perineal hypospadias frequently is associated with ventral curvature. We recently reported findings in 70 consecutive patients: 19% were straight after degloving, 31% underwent a single dorsal plication for curvature 30 [1]. In contrast, the authors state that only 10% of their primary cases had ventral curvature that apparently was usually <30 , as most were corrected by dorsal plication. Again the question arises: how many of their patients had ‘severe’ hypospadias?
Antielevation syndrome after bilateral anterior transposition of the inferior oblique muscles: incidence and prevention.

Background: Unilateral 1 and bilateral 2 anterior transpositions of the inferior oblique muscle (ATIOs) for primary inferior oblique (IO) muscle overaction may produce apparent new or recurrent overaction of the contralateral IO muscle. This effect has been termed “antielevating” and can produce overaction of the contralateral elevators in adduction that mimics recurrent or new overaction of the IO muscle of the other eye. This phenomenon may be termed the antielevation syndrome (AES). Kushner 2 has hypothesized that this complication of the ATIO is produced primarily by the posterior fibers of the IO muscle. The purpose of this study is to correlate the frequency of this syndrome in a large series of patients with the mm of lateral displacement (spreading) of the IO muscle reattachment site. Methods: There was a combination of 123 patients who received ATIO from Mims and 77 patients who received ATIO from Kushner. 2 ATIO was performed according to a previously published technique. 3 Results: All 16 patients (14 from Mims and 2 from Kushner) with AES had received bilateral anterior transposition of the posterior fibers of the IO muscle to at least 2 mm anterior to the lateral end of the inferior rectus (IR) muscle with spreading laterally 3 to 5 mm. Among children who had the posterior fibers of their IO muscles placed 2 to 4 mm anterior to a line drawn laterally from the insertion of the IR muscle, the incidence of AES was significantly larger with more spreading out of the new IO muscle insertion. Conclusions: AES may be prevented by attaching the posterior fibers of the IO muscle no more than 2 mm lateral to the IR muscle insertion site. This complication responds to bilateral nasal IO muscle myectomy in many cases. (J AAPOS 1999;3:333-6)
Widespread Cortical Dysfunction in Schizophrenia: The FBIRN Imaging Consortium

This Special Theme issue presents a series of related papers describing fMRI data collected as part of a multi-site brain imaging consortium, the Functional Imaging Biomedical Informatics Research Network (FBIRN) on the same subject population (∼125 patients and ∼125 controls), a larger sample than would have been possible from a single-site, and from a broader clinical and demographic range of patients. Potkin et al observe cortical inefficiency during retrieval of items from memory but not during encoding of those items; Brown et al showed that the lawful relationship between memory retrieval time and neural activation is decoupled in patients with schizophrenia. Wible et al analyzed the same memory data and report activations of left auditory and parietal cortices are especially abnormal in patients who tend to hallucinate. Using an auditory target detection task, Ford et al report abnormal activation of left primary auditory cortex in the hallucinators. A multivariate analysis of those auditory data by Kim et al found differences in connectivity in patients and controls. These studies on the same patient sample suggest that abnormal circuitry characterizes schizophrenic performance in both auditory target detection and memory retrieval, and that patients who hallucinate have reduced left auditory cortical activation on both tasks. Segall et al report anatomical differences between patients and controls in the largest sample yet published. Finally, Potkin et al. identified six genes that influence DLPFC activation and have functions related to forebrain development and stress responses in schizophrenia. These related publications indicate the power of multisite neuroimaging.
Theory of gain spectra for quantum cascade lasers and temperature dependence of their characteristics at low and moderate carrier concentrations

We have developed a theory describing the operation of lasers based on intersubband transitions in a quantum well. The theory combines a first-principles description of the intersubband lineshape and the optical gain with kinetic models for carrier heating. The theory is consistent with the experimental data available and suggests new ways of improving the laser design for room-temperature operation with high output power. At low carrier concentrations, it is possible to achieve positive values of the gain at room temperature even in the absence of an overall population inversion between quantum-well subbands. For higher (but still moderate) concentrations, the theory predicts a peculiar dependence of the output wavelength on the pump current, including a regime where the lasing wavelength switches "digitally" between two stable values.
Social influences on the development of planning in advance and during action

This paper reports on a study of the development of children's planning skills with particular attention to the development of planning in advance of action as contrasted with planning during the c...