cssi/SciSciGPT-SciSciNet huggingface dataset:
Redox control of liver fibrosis in aged mice

Glutaredoxin-1 (Glrx) removes glutathione (GSH) adducts of protein thiols (S-glutathionylated protein) and controls cellular signaling and gene transcription. Human lung fibrosis decreases Glrx protein expression, and conversely, Glrx administration attenuates bleomycin-induced lung fibrosis in mice. We previously showed that Glrx knockout (KO) mice develop liver steatosis and diet-induced liver fibrosis. Aging is another factor which promotes liver fibrosis. Objective We investigated whether Glrx expression can affect age-induced liver fibrosis in mice and provoke functional changes in isolated hepatocytes and hepatic stellate cells. Methods Aged liver samples of 4, 12, and 18 months old mice were obtained from NIA. Liver samples from global Glrx transgenic (TG) and wild-type (WT) mice were collected at age 9-24 months. Liver sections were stained with Picrosirius red to assess collagen deposition and fibrotic areas. Hepatocytes and hepatic stellate cells were isolated from mouse liver to examine the effects of Glrx overexpression or ablation on hepatocyte apoptosis and collagen synthesis in hepatic stellate cells. Results Liver fibrosis significantly increased during aging, while Glrx expression levels tended to decrease. Overexpressed Glrx attenuated collagen accumulation in Glrx TG mice compared to aged WT mice. In vitro studies showed that Glrx KO enhanced Fas-mediated apoptosis in hepatocytes. Also, Glrx KO increased TGFb-induced fibrotic markers (collagen, aSM-actin) in hepatic stellate cells. Conclusion Aging increased liver fibrosis which is likely related to a decline in Glrx expression. In contrast, Glrx overexpression significantly attenuated the age-induced changes in liver fibrosis. Glrx protected hepatocytes from apoptosis and hepatic stellate cells from fibrotic activation. Thus, upregulated Glrx may ameliorate liver fibrosis in aged animals. (Supported by R01HL133013, R03AG051857, R01DK103750).
Photonic Crystal Fiber (PCF) Raman Amplifier

An accurate design for a Photonic Crystal fiber (PCF) Raman amplifier has been developed. In this PCF, the geometric parameters, Raman gain coefficient, effective mode area, the Germania concentration in the doped area, and dispersion and confinement loss characteristics have been investigated at 1.55 μm. The flexibility of the geometrical parameters and doping concentrations that allowed to optimize these parameters to increase the amplifier efficiency have been studied. For ⋀ = 3.2 μm, \( d_{1} = 1.44\,\upmu{\rm m},d_{2} = 1.47\;\upmu{\rm m} \), Raman gain coefficient of 9.25 \( {\rm W}^{ - 1} {\rm km}^{ - 1} \) and almost zero dispersion are achieved for 7.5 km low loss hexagonal Photonic Crystal Fiber with an effective area of 20 \( \upmu{\rm m}^{2} . \)
Valid inequalities for concave piecewise linear regression

Abstract We consider the problem of fitting a concave piecewise linear function to multivariate data using the Least Absolute Deviation objective. We propose new valid inequalities for the problem using the properties of concave functions. Results with univariate data show that the proposed valid inequalities improve the root relaxation lower bound, permitting significant improvements in solution time.
Effect of impact factor and discipline on journal data sharing policies

Data sharing is crucial to the advancement of science because it facilitates collaboration, transparency, reproducibility, criticism, and re-analysis. Publishers are well-positioned to promote shar...
Multispectral short-range imaging through artificial fog

This paper attempts to quantify thermal infrared (both longwave and midwave), shortwave infrared, and visible-light sensor performance under different test-chamber fogs. We find that the performance of LWIR imaging is impacted significantly less by light-to-moderate fog than the other two IR sensors and the visible imager. The paper recommends additional fog chamber tests that will be useful for the development of imaging simulation capability that accurately models fog across these wavebands.
Low Cost and High Density Packaging Technologies for Ultra Small IoT Computing Systems

The recent progress in low power chip development has allowed us to put the 3D chip packaging technology into a practical use. In this paper, two key packaging technologies, which are wafer bumping and 3D chip stacking, to implement ultra-small IoT systems with low cost are introduced.
Assessment of an ensemble of machine learning models toward abnormality detection in chest radiographs

Respiratory diseases account for a significant proportion of deaths and disabilities across the world. Chest X-ray (CXR) analysis remains a common diagnostic imaging modality for confirming intra-thoracic cardiopulmonary abnormalities. However, there remains an acute shortage of expert radiologists, particularly in under-resourced settings, resulting in severe interpretation delays. These issues can be mitigated by a computer-aided diagnostic (CADx) system to supplement decision-making and improve throughput while preserving and possibly improving the standard-of-care. Systems reported in the literature or popular media use handcrafted features and/or data-driven algorithms like deep learning (DL) to learn underlying data distributions. The remarkable success of convolutional neural networks (CNN) toward image recognition tasks has made them a promising choice for automated medical image analyses. However, CNNs suffer from high variance and may overfit due to their sensitivity to training data fluctuations. Ensemble learning helps to reduce this variance by combining predictions of multiple learning algorithms to construct complex, non-linear functions and improve robustness and generalization. This study aims to construct and assess the performance of an ensemble of machine learning (ML) models applied to the challenge of classifying normal and abnormal CXRs and significantly reducing the diagnostic load of radiologists and primary-care physicians.
Introduction to thermal therapy and immunotherapy: at the crossroads of new discovery.

We are very pleased to publish a significant and diverse collection of primary studies and reviews in this special issue entitled Thermal Therapy and Immunotherapy: at the Crossroads of New Discove...
Triplet 23S state of a quantum dot in a magnetic field: A ‘Quantal Newtonian’ first law study

Abstract The triplet 2 3 S state of a 2-electron 2-dimensional quantum dot in a magnetic field is studied via a complementary perspective of Schrodinger–Pauli theory. The perspective is that of the individual electron via its equation of motion or ‘Quantal Newtonian’ first law. According to the law, each electron experiences an external and an internal field, the sum of which vanishes. The external field is the sum of the binding and Lorentz fields. The internal field is a sum of the electron-interaction, kinetic, differential density, and internal magnetic fields. The energy is expressed in integral virial form in terms of these fields. The quantal sources of the density; paramagnetic, diamagnetic, and magnetization current densities; pair-correlation density; the Fermi–Coulomb hole charge; and the single-particle density matrix are obtained, and from them the corresponding fields determined. The fields are shown to satisfy the first law.
Chapter VI – Form Perception

Publisher Summary This chapter discusses the form perception in nonhuman primates. The major methodological considerations in studying form perception are in specifying the stimulus and in insuring that the stimulus is appropriate for S. To obtain ecological validity, stimuli used should be representative of the real situations to which one wishes to generalize. This argues against presenting animal Ss with geometric forms and argues for stimuli associated with the Menzel jumping stand, the Delta Regional General Test Apparatus, and the Menzel obstruction box, which are a tree, a jungle, and a river, respectively. Nevertheless, for all their ecological validity, such situations have not provided extensive information about the mechanisms of form perception by nonhuman primates. There is no quick and easy way to determine which physical measurements have the greatest psychological relevance for pattern preference and discrimination. The most elusive contextual effect is provided by simultaneous discrimination of dissimilar forms. When S learns to make a particular response to a singly represented stimulus, it is seemingly impossible to apply this knowledge with assurance to problems in which two forms are presented, because one provides a context for the other.
Multi-factor Stock Selecting Model Based on Residual Net and LSTM Deep Learning Algorithm

This paper builds a multi-factor stock selection model based on optimized deep learning algorithms, using SFS, GA and XGBoost for factor combination and feature selection. Besides, applying Multi-LR to integrate Residual Net and LSTM to predict the stock's weekly change, which better simulates the randomness, information asymmetry and timing of financial markets. The quantitative models in this paper have excellent prediction accuracy, return and stability.
Cross-Center Virtual Education Fellowship Program for Early-Career Researchers in Atrial Fibrillation

Background: It is estimated that over 46 million individuals have atrial fibrillation (AF) worldwide, and the incidence and prevalence of AF are increasing globally. There is an urgent need to acce...
Numerical simulation of falling film flow hydrodynamics over round horizontal tubes

Abstract The performance of a falling film heat exchanger depends significantly on the flow characteristics and the associated heat transfer in the liquid film flowing over its horizontal tube surfaces. In this study, three-dimensional numerical simulations based on the Volume of Fluid method are conducted to investigate the hydrodynamic behavior of a falling film over horizontal round tubes with diameter and tube-to-tube spacings each of 16 mm. Using a mixture of water and ethylene glycol, the simulations comprise a range of flow rates (Re = 15 to 210) that covers all basic intertube flow modes i.e., droplet, jet (in-line and staggered), and sheet mode. InterFoam, a two-phase incompressible flow solver in OpenFOAM, has been used to simulate the flow field. The computational model agrees well with the available experimental data. The numerical results present the variation of the liquid film thickness and the film interface velocity over the tube surface for all the flow modes. In the droplet mode, the impact of the droplet on the tube produces liquid waves that interact with the neighboring waves and are seen to travel on the tube surface downstream of the impingement region and the region between the impingement sites. The movement of these waves causes a significant change in the film thickness over the tube surface, quantitatively, by more than 350% during a short interval of the droplet mode cycle. After the droplet impact, the liquid bridge formed in between the tubes undergoes necking and finally bifurcates under the Raleigh-Plateau instability mechanism at a location of spacing-to-tube-diameter ratio of 0.8 from the top surface of the impinging tube and produces satellite droplets in between the tubes. In the steady in-line jet mode, the liquid from the neighboring jets do not interact with each other, and the bulk liquid flows downstream of the impingement region. A dimple around the jet impingement region is formed where the film thickness changes by around 40%. The base of the impinging jets was seen to possess ripples due to the Raleigh-Plateau instability with wavelengths ranging from 0.3 - 1.0 times the capillary length scale. For the steady staggered jet mode, the liquid jet impinges on the tube surface, which then spreads rapidly and interacts with the adjacent jet liquid to develop crest and stable segments along the tube length direction. The ratio of the film thickness between the crest and the stable segments was found to be 1.7. Finally, for the sheet mode, due to the formation of surface waves in the liquid sheet, interfacial waves are seen to travel along the tube periphery with amplitudes of about ± 20% of the nominal film thickness. These flow mode characteristics alter the film thickness and flow velocity distribution over the tube surface and are expected to play an essential role in the surface heat transfer behavior over round horizontal tubes. A set of correlations have been presented to predict the film thickness and interfacial velocity over the tube surface for each of the studied modes of flow with reasonable accuracy.
[SG] and Final Consonant Allophony in Tz'utujil

This paper considers two phenomena in Tz'utujil (Mayan) phonology: final sonorant devoicing and final aspiration of plain (pulmonic) stops and affricates. Both occur word-internally in coda position, as well as word-finally. I present an Optimality-Theoretic (OT) analysis which accounts for both of these phenomena via positional constraints on [spread glottis] ([SG]). This analysis also accounts for attested variation in final aspiration and devoicing across the Mayan language family and predicts an implicational relationship between final nasal devoicing, final sonorant devoicing, and final obstruent aspiration. Final sonorant devoicing is typologically rare and somewhat difficult to explain in terms of phonetic motivation. Tz'utujil may be able to provide insight into the typology of laryngeal features and the roles of contrast and phonetic pressures in phonology.
On the use of SRIM for calculating vacancy production: Quick calculation and full-cascade options

Abstract The vacancy production behavior for a broad range of incident ion-target combinations were examined by using both the full cascade (F-C) and quick calculation of damage (Q-C) options of Stopping and Range of Ions in Matter (SRIM-2013) code. Vacancy production for each option was evaluated using both the convenient vacancy text file in SRIM, and by manual manipulation of the energy transfer, ionization, and phonon text file data to calculate the depth-dependent damage energy for the Norgett-Robinson-Torrens (NRT) defect production model. The F-C vacancy text file method was observed to overpredict vacancy production by a factor of ~1.1 to 4 times when compared to values calculated using the F-C damage energy method or either of the SRIM Q-C methods. Based on our extensive data set obtained for 142 unique bombarding ion-target combinations, we show that the SRIM F-C vacancy text file method should not be used for vacancy production calculations. This error appears to be due to mischaracterization within the SRIM F-C option of some near-threshold replacement events as vacancies instead of replacements. Use of the latest SRIM stopping powers in the SRIM F-C approach provides a better calculation of electronic and nuclear stopping compared to the Lindhard stopping power analytical approximation used to calculate the damage energy of recoil atoms in the SRIM Q-C option, and therefore SRIM F-C approach is deemed to provide the best accuracy for vacancy production (within the binary collision approximation) as long as the damage energy method is used. Alternately, the SRIM Q-C option using either the vacancy.txt or damage energy method provides relatively fast calculation speeds with moderate quantitative differences from the F-C damage energy results (~0 to ~ 30% for the investigated ion-target cases).
Student-faculty co-creation of experiential learning in health systems science.

INTRODUCTION: Health Systems Science (HSS) teaches students critical skills to navigate complex health systems, yet medical schools often find it difficult to integrate into their curriculum due to limited time and student disinterest. Co-developing content with students and teaching through appropriate experiential learning can improve student engagement in HSS coursework. METHODS: Medical students and faculty co-developed a patient outreach initiative during the early phases of the COVID-19 pandemic and integrated that experience into a new experiential HSS elective beginning May 2020. Students called patients identified as high-risk for adverse health outcomes and followed a script to connect patients to healthcare and social services. Subsequently, this initiative was integrated into the required third-year primary care clerkship. RESULTS: A total of 255 students participated in HSS experiential learning through the elective and clerkship from May 2020 through July 2021. Students reached 3,212 patients, encountering a breadth of medical, social, and health systems issues; navigated the EMR; engaged interdisciplinary professionals; and proposed opportunities for health systems improvement. DISCUSSION AND CONCLUSION: This educational intervention demonstrated the opportunity to partner with student-led initiatives, coproducing meaningful educational experiences for the learners within the confines of a busy medical curriculum.
Chronic CO2 retention stimulates gastric acid secretion and induces gastric mucosal hyperplasia in rats

We have postulated that chronic CO2 retention (e.g., U.S. Naval submariners underway, under-ventilated workspaces, hypoventilation disorders) causes chronic vagal stimulation of gastric mucosal blo...
Lithospheric Stratigraphy Beneath the Southern Rocky Mountains, USA

The Continental Dynamics-Rocky Mountains (CD-ROM) experiment seeks to constrain the evolution, stabilization and modification of the continental lithosphere of the southern Rocky Mountains. In this paper, we present the detailed results of images constructed using broadband teleseismic receiver functions of the continental lithosphere in the interior western United States, with focus on the southern Rocky Mountains. The targets of this experiment are the Cheyenne suture, an Archean continent/Proterozoic arc terrane boundary, and the Jemez suture/volcanic lineament, that separates the Proterozoic Mazatzal and Yavapai provinces. The main features observed across the Cheyenne belt are a thick lithosphere (>150 km) as evidenced by changes in the mantle lithospheric layering across the Cheyenne Suture. Underlying the Cheyenne suture is a Proterozoic oceanic slab fragment, most plausibly tectonically emplaced beneath the rifted Wyoming margin. Below the Jemez volcanic lineament two strong sub-crustal layers are imaged down to 100 km depth that reside within the tomographically imaged low velocity zone. This layering is interpreted to map the depth extent of the lithosphere and most plausibly results from changes in chemical composition of the lithosphere. In contrast to the Cheyenne suture, little evidence is seen beneath the Jemez lineament for a suture that extends through the lithosphere. Our conclusions are that beneath the Archean-Proterozoic Cheyenne belt the lithosphere is at least 150 km thick and preserves 1.7 Ga. lithospheric scale structure, while across the Proterozoic-Proterozoic Jemez boundary, the lithosphere is at least 100 km thick.
Lanthanum inhibits steady-state turnover of the sarcoplasmic reticulum calcium ATPase by replacing magnesium as the catalytic ion.

LaATP is shown to be an effective inhibitor of the calcium ATPase of sarcoplasmic reticulum because the binding of LaATP to cE.Ca2 results in the formation of lanthanum phosphoenzyme, which decays slowly. Steady-state activity of the calcium ATPase in leaky sarcoplasmic reticulum vesicles is inhibited 50% by 0.16 microM LaCl3 (15 nM free La3+, 21 nM LaATP) in the presence of 25 microM Ca2+ and 49 microM MgATP (5 mM MgSO4, 100 mM KCl, 40 mM 4-morpholinepropanesulfonic acid, pH 7.0, 25 degrees C). However, 50% inhibition of the uptake of 45Ca and phosphorylation by [gamma-32P]ATP in a single turnover experiment requires 100 microM LaCl3 (28 microM free La3+) in the presence of 25 microM Ca2+; this inhibition is reversed by calcium but inhibition of steady-state turnover is not. Therefore, binding of La3+ to the cytoplasmic calcium transport site is not responsible for the inhibition of steady-state ATPase activity. The addition of 6.7 microM LaCl3 (1.1 microM free La3+) has no effect on the rate of dephosphorylation of phosphoenzyme formed from MgATP and enzyme in leaky vesicles, while 6.7 mM CaCl2 slows the rate of phosphoenzyme hydrolysis as expected; 6.7 microM LaCl3 and 6.7 mM CaCl2 cause 95 and 98% inhibition of steady-state ATPase activity, respectively. This shows that inhibition of ATPase activity in the steady state is not caused by binding of La3+ to the intravesicular calcium transport site of the phosphoenzyme. Inhibition of ATPase activity by 2 microM LaCl3 (0.16 microM free La3+, 0.31 microM LaATP) requires greater than 5 s, which corresponds to approximately 50 turnovers, to reach a steady-state level of greater than or equal to 80% inhibition. Inhibition by La3+ is fully reversed by the addition of 0.55 mM CaCl2 and 0.50 mM EGTA; this reactivation is slow with t1/2 approximately 9 s. Two forms of phosphoenzyme are present in reactions that are partially inhibited by La3+: phosphoenzyme with Mg2+ at the catalytic site and phosphoenzyme with La3+ at the catalytic site, which undergo hydrolysis with observed rate constants of greater than 4 and 0.05 s-1, respectively. We conclude, therefore, that La3+ inhibits steady-state ATPase activity under these conditions by replacing Mg2+ as the catalytic ion for phosphoryl transfer. The slow development of inhibition corresponds to the accumulation of lanthanum phosphoenzyme. Initially, most of the enzyme catalyzes MgATP hydrolysis, but the fraction of enzyme with La3+ bound to the catalytic site gradually increases because lanthanum phosphoenzyme undergoes hydrolysis much more slowly than does magnesium phosphoenzyme.(ABSTRACT TRUNCATED AT 400 WORDS)
Predicting early allograft failure and mortality after liver transplantation: the role of the postoperative model for end-stage liver disease score.

Early allograft dysfunction (EAD) is a serious complication after liver transplantation (LT). There is no uniform definition of EAD, and most definitions are based on arbitrary laboratory values. The aim of this study was to devise a definition of EAD that maximizes the predictive power for early death and graft failure. In this single-center, retrospective study, the ability of the international normalized ratio (INR), total bilirubin, aspartate aminotransferase (AST), physiological Model for End-Stage Liver Disease (MELD) score, and serum albumin levels within 7 days after LT to predict 90-day mortality or graft loss was compared with 2 previously used definitions of EAD: (1) peak total bilirubin level >10 mg/dL on days 2 to 7 and (2) either a total bilirubin level >10 mg/dL or an INR >1.6 on day 7 or an AST or alanine aminotransferase level >2000 IU/L within the first 7 days. Of 572 enrolled LT patients 38 died or required retransplantation within 90 days. Peak INR, total bilirubin level, AST levels, and MELD scores were predictors of 90-day graft failure. MELD score on postoperative day 5 was the best predictor with an area under the curve of the receiver operating characteristic curve of 0.812 (95% CI: 0.739-0.886, P 18.9 on postoperative day 5 was a better predictor than any other laboratory value or definition of EAD. This study has demonstrated that the MELD score can be a useful tool not only for pretransplant graft allocation but also for postoperative risk stratification.
Laboratory Astrophysics and Scaling

This chapter is a summary of lectures intended to introduce the concept of scaling to graduate students. Specifically, we address whether astrophysical phenomena may be addressed using ‘scaled’ versions of the same processes in experiments in the laboratory. Recent (and ongoing) advances in laser facility capabilities, such as higher temperatures and Mach numbers, are making such scaled hydrodynamical and even magneto-hydrodynamical experiments possible. The general concept of scaling, relevant equations, and some applications are presented.
Software engineering of machine control systems: an approach to lifecycle economics

Describes a domain modeling process and framework for use in lifecycle engineering of software to monitor and control agile machining equipment. The authors focus on an approach of defining initial requirements in a way that facilitates evolution. The process has been used in an industrial case study.
Recombinant BCG Expressing Mycobacterium ulcerans Ag85A Imparts Enhanced Protection against Experimental Buruli ulcer.

Buruli ulcer, an emerging tropical disease caused by Mycobacterium ulcerans (MU), is characterized by disfiguring skin necrosis and high morbidity. Relatively little is understood about the mode of transmission, pathogenesis, or host immune responses to MU infection. Due to significant reduction in quality of life for patients with extensive tissue scarring, and that a disproportionately high percentage of those affected are disadvantaged children, a Buruli ulcer vaccine would be greatly beneficial to the worldwide community. Previous studies have shown that mice inoculated with either M. bovis bacille Calmette–Guerin (BCG) or a DNA vaccine encoding the M. ulcerans mycolyl transferase, Ag85A (MU-Ag85A), are transiently protected against pathology caused by intradermal challenge with MU. Building upon this principle, we have generated quality-controlled, live-recombinant strains of BCG and M. smegmatis which express the immunodominant MU Ag85A. Priming with rBCG MU-Ag85A followed by an M. smegmatis MU-Ag85A boost strongly induced murine antigen-specific CD4+ T cells and elicited functional IFNγ-producing splenocytes which recognized MU-Ag85A peptide and whole M. ulcerans better than a BCG prime-boost vaccination. Strikingly, mice vaccinated with a single subcutaneous dose of BCG MU-Ag85A or prime-boost displayed significantly enhanced survival, reduced tissue pathology, and lower bacterial load compared to mice vaccinated with BCG. Importantly, this level of superior protection against experimental Buruli ulcer compared to BCG has not previously been achieved. These results suggest that use of BCG as a recombinant vehicle expressing MU antigens represents an effective Buruli ulcer vaccine strategy and warrants further antigen discovery to improve vaccine efficacy.
Lightweight Formal Methods

Formal methods have offered great benefits, but often at a heavy price. For everyday software development, in which the pressures of the market don't allow full-scale formal methods to be applied, a more lightweight approach is called for. I'll outline an approach that is designed to provide immediate benefit at relatively low cost. Its elements are a small and succinct modelling language, and a fully automatic analysis scheme that can perform simulations and find errors. I'll describe some recent case studies using this approach, involving naming schemes, architectural styles, and protocols for networks with changing topologies. I'll make some controversial claims about this approach and its relationship to UML and traditional formal specification approaches, and I'll barbeque some sacred cows, such as the belief that executability compromises abstraction.
NQS effects on MOSFET's terminal currents

Channel segments approach is used to investigate NQS (non-quasi-static) effect on MOSFET's behavior. For the first time, NQS effect on terminal currents is examined in addition to channel charge. It is demonstrated that conventional analysis and modeling approach for NQS effect, which only takes into consideration the NQS effect on channel charge, is not sufficient. Both channel charge variation and terminal current variation under NQS working mode need to be included in NQS models for accurate prediction of device behavior. It is found that NQS effect is more significant in saturation region than that in linear region
Computerized mapping of fibrillation in normal ventricular myocardium.

It is well known that the ability to fibrillate is intrinsic to a normal ventricle that exceeds a critical mass. The questions we address are how is ventricular fibrillation (VF) initiated and perpetuated in normal myocardium, and why is VF not seen more often in the general population if all ventricles have the ability to fibrillate. To study the mechanisms of VF, we used computerized mapping techniques with up to 512 channels of simultaneous multisite recordings for data acquisition. The data were then processed for dynamic display of the activation patterns and for mathematical analyses of the activation intervals. The results show that in normal ventricles, VF can be initiated by a single strong premature stimulus given during the vulnerable period of the cardiac cycle. The initial activations form a figure-eight pattern. Afterward, VF will perpetuate itself without any outside help. The self-perpetuation itself is due to at least two factors. One is that single wave fronts spontaneously break up into two or more wavelets. The second is that when two wavelets intersect perpendicular to each other, the second wavelet is broken by the residual refractoriness left over from the first wavelet. Mathematical analyses of the patterns of activation during VF revealed that VF is a form of chaos, and that transition from ventricular tachycardia (VT) to VF occurs via the quasiperiodic route. In separate experiments, we found that we can convert VF to VT by tissue size reduction. The physiological mechanism associated with the latter transition appears to be the reduction of the number of reentrant wave fronts and wandering wavelets. Based on these findings, we propose that the reentrant wave fronts and the wandering wavelets serve as the physiological equivalent of coupled oscillators. A minimal number of oscillators is needed for VF to perpetuate itself, and to generate chaotic dynamics; hence a critical mass is required to perpetuate VF. We conclude that VF in normal myocardium is a form of reentrant cardiac arrhythmia. A strong electrical stimulus initiates single or dual reentrant wave fronts that break up into multiple wavelets. Sometimes short-lived reentry is also generated during the course of VF. These organized reentrant and broken wavelets serve as coupled oscillators that perpetuate VF and maintain chaos. Although the ability to support these oscillators exists in a normal ventricle, the triggers required to generate them are nonexistent in the normal heart. Therefore, VF and sudden death do not happen to most people with normal ventricular myocardium.
Associations between syntax and the lexicon among children with or without ASD and language impairment.

Five groups of children defined by presence or absence of syntactic deficits and autism spectrum disorders (ASD) took vocabulary tests and provided sentences, definitions, and word associations. Children with ASD who were free of syntactic deficits demonstrated age-appropriate word knowledge. Children with ASD plus concomitant syntactic language impairments (ASDLI) performed similarly to peers with specific language impairment (SLI) and both demonstrated sparse lexicons characterized by partial word knowledge and immature knowledge of word-to-word relationships. This behavioral overlap speaks to the robustness of the syntax–lexicon interface and points to a similarity in the ASDLI and SLI phenotypes.
COAction: Collaborative Option Awareness impact on collaborative decision making

Previously, we used exploratory modeling to forecast a landscape of plausible outcomes for a set of options. Outcomes were displayed as a set of box-plots that illustrate outcome-frequencies distributed across an evaluative dimension (e.g., cost, score, or utility). Such a display depicts a “decision space” because it directly supports comparing and deciding among available courses of action rather than simply providing the facts about the situation (the “situation space”). Our previous research showed that such decision spaces provide what we termed “option awareness” - an ability to determine robust options that will have good outcomes across the broadest swath of plausible futures. Moreover, such option awareness resulted in increased confidence in the chosen option. When extending this approach to collaborative decision making, issues arise when team members' decision spaces are in conflict - when merely jointly executing the most robust individual options does not yield the most robust collaborative option because each individual's decision space does not account for the synergy that may emerge from collaboration. The current paper describes issues for providing collaborative decision support. It includes a proposed categorization of different types of synergies and defines conflicted versus unconflicted cases. Further, this paper describes experiments that are now underway to determine the robustness of joint decisions, the confidence with which these decisions are made, and the nature of the coordination among teams of decision makers.
Analysis of gene expression in Treponema denticola with differential display polymerase chain reaction

Treponema denticola is an oral spirochete associated with the periodontal diseases. A great deal of the molecular components of T. denticola will be learned soon since its genome sequence project is on the way. One of the most important works after genome sequence is to analyze the function of these genes and their regulation. However, like many other oral pathogens, there are currently a very limited number of molecular and genetic tools available to study gene expression in T. denticola. In this article, we describe a method of adapting differential display polymerase chain reaction (ddPCR) for use in the T. denticola system. To test for effectiveness of this protocol, we used three different temperature conditions, 4 degrees C, 25 degrees C and 42 degrees C, to test for differential gene expression. With various ddPCR conditions, we found a number of genes that were expressed differentially. Some of these differentially expressed genes were cloned and sequenced and found to be homologous with the known temperature-regulated genes, including HtrA. The study indicates that the ddPCR method can be effectively used in T. denticola for analyzing gene expression under various conditions.
ASSOCIATION OF ELECTROACTIVE COUNTERIONS WITH POLYELECTROLYTES. 6. ELECTROSTATIC AND COORDINATIVE BINDING OF RU3+/2+ CENTERS TO A COPOLYMER OF ACRYLIC ACID AND ACRYLONITRILE

A random copolymer of acrylic acid and acrylonitrile was prepared in which the functionality on the polymer chain consisted of 93% carboxylic acid groups, 4.1% nitrile groups, and 2.9% acid anhydride groups. The nitrile groups were used to coordinate Ru(NH_3)_5^(2+) centers to the copolymer. The anionic carboxylate groups produced at pH values above ∼3.5 were used to bind Ru(NH_3)_6^(3+) counterions to the resulting polyanionic copolymer. The electrochemical oxidation or reduction of the two redox centers bound to the copolymer were used to estimate diffusion coefficients for the copolymer. Reasonable agreement was obtained between the values obtained from both electroactive redox groups. The diffusion coefficient exhibited a strong dependence on pH that reflected changes in the structure of the copolymer as it was converted from its neutral to its polyanionic form. The rate of the reaction between the Ru(NH_3)_5OH_2^(2+) complex and the nitrile groups of the copolymer increased significantly with pH because electrostatic binding of the cation to the polyanionic copolymer increased the concentration of the complex in the vicinity of the nitrile groups. Adsorption of the copolymer on the surface of the electrodes interfered with the oxidation of Ru(NH_3)_5^(2+) groups coordinated to the dissolved copolymer but not with Ru(NH_3)_6^(3+) counterions electrostatically bound to the polyanion. A possible explanation for the contrasting behavior is suggested.
Two Drosophila Genes That Encode the α and β Subunits of the Brain Soluble Guanylyl Cyclase

We identified two Drosophila genes (dgcα1 and dgcβ1) that encode the soluble guanylyl cyclase α and β subunits, respectively. The putative Dgcα1 protein is 76 kDa, has 35% amino acid identity with previously isolated α subunits, and was immunolocalized to the adult retina, to the optic lobes, and throughout the brain neuropil. The Dgcβ1 protein is 86 kDa and exhibits 59% amino acid identity with the rat β1 protein. However, the Dgcβ1 protein has an additional 118 amino acids inserted near the amino terminus, which makes it significantly larger than the rat β1. The Dgcβ1 protein was immunolocalized to the optic lobes and throughout the brain neuropil, with no detectable expression in the retina. The Dgcα1 and Dgcβ1 cDNAs were stably transfected into human kidney 293 cells. Expression of the individual subunits and mixing of the individually expressed subunits failed to generate significant guanylyl cyclase activity. Only coexpression of the subunits resulted in significant guanylyl cyclase activity. Our results indicate that Dgcα1 and Dgcβ1 are soluble guanylyl cyclase α and β subunits that are capable of forming a functional guanylyl cyclase heterodimer.
Acute acalculous cholecystitis in the critically ill: risk factors and surgical strategies

Acute acalculous cholecystitis (AAC) is characterized by severe gallbladder inflammation without cystic duct obstruction. Critical illness and neurological deficits are often associated with AAC, and early radiologic imaging is necessary for the detection and timely treatment of AAC. In critically ill patients, effective surgical management is difficult. This review examines the three common surgical treatments for AAC (open cholecystectomy (OC), laparoscopic cholecystectomy (LC), or percutaneous cholecystostomy (PC)), their prevalence in current literature, and the perioperative outcomes of these different approaches using a large retrospective database. This review examined literature gathered from PubMed and Google Scholar to select more than 50 sources with data pertinent to AAC; of which 20 are described in a summary table. Outcomes from our previous research and several updated results were obtained from the University HealthSystem Consortium (UHC) database. LC has proven effective in treating AAC when the risks of general anesthesia and the chance for conversion to OC are low. In critically ill patients with multiple comorbidities, PC or OC may be the only available options. Data in the literature and an examination of outcomes within a national database indicate that for severely ill patients, PC may be safer and met with better outcomes than OC for the healthier set of AAC patients. We suggest a three-pronged approach to surgical resolution of AAC. Patients that are healthy enough to tolerate LC should undergo LC early in the course of the disease. In critically ill patients, patients with multiple comorbidities, a high conversion risk, or who are poor surgical candidates, PC may be the safest and most successful intervention.
First-Stage Urethroplasty: Utility in the Modern Era

Objectives To describe the current role of first-stage urethroplasty and its success as a management option in patients with complex anterior urethral stricture disease. Methods We reviewed our urethral stricture database to identify patients managed with a staged urethral reconstruction or permanent first-stage urethroplasty. We noted patient age, etiology of stricture disease, location and length of stricture, location of neomeatus, indication for a staged approach, follow-up, and failure rate. Results A total of 38 men with a median age of 53 years met the inclusion criteria. The etiology of stricture disease varied, most commonly prior hypospadias repair (n = 9 [24%]) and lichen sclerosis (n = 6 [16%]). Location of stricture disease varied throughout the anterior urethra. Median stricture length was 5 cm. First-stage urethroplasty was accomplished with a penile shaft neomeatus in 13 patients (34%) and a perineal neomeatus in 25 (66%). Median follow-up was 22 months. Postoperative urethral dilation was required in 7 patients (18%). No patient has required an indwelling urethral catheter, suprapubic cystostomy, or urinary diversion. Of 38 patients, 9 (24%) have undergone a second-stage urethroplasty. Conclusions The first-stage urethroplasty produces unobstructed voiding with few complications in high-risk patients. Few patients elect to have a second-stage urethroplasty performed. This is an old but not obsolete concept. We have presented modifications in technique to optimize success.
Methods for the metabolic quantification of regional myocardial ischemia

Abstract An adequate balance between oxygen supply and demand is a basic requirement for normal cardiac function. When oxygen supply does not meet the demand, progressive cellular damage occurs leading to cardiac dysfunction and, ultimately, tissue death. While traditionally “ischemia” has been defined as decreased oxygen supply secondary to a decrease in blood flow, and “hypoxia” as decreased oxygen supply secondary to a decrease in oxygen tension, this review defines ischemia in its broader sense, namely as a pathophysiologic state in which there is a lack of oxygen relative to the demand for it. In a large number of experimental studies involving the heart, there is need to promptly recognize the ischemic state, to monitor its course in vivo, and to quantify it. Because of cardiac autoregulatory mechanisms, research methods which attempt to quantify supply (e.g., measurement of myocardial blood flow) and/or demand (e.g., measurement of myocardial oxygen consumption) do not necessarily reflect the status of the balance between supply and demand. An imbalance between myocardial supply and demand is more likely to be reflected by metabolic fluxes and by the accumulation of products specific to the ischemic state. Thus, the purpose of this review is to summarize the various methods available to the cardiac surgical investigator today for the metabolic quantification of myocaridal ischemia. Due to the complexity of the heart and its inherent regional differences, myocardial ischemic changes are frequently regional in nature. Thus, this review will address metabolic methods for the regional quantification of myocardial ischemia.
An activation domain within the walleye dermal sarcoma virus retroviral cyclin protein is essential for inhibition of the viral promoter.

Walleye dermal sarcoma virus (WDSV) is a complex retrovirus associated with seasonal dermal sarcomas. Developing tumors have low levels of accessory gene transcripts, A1 and B, and regressing tumors have high levels of full-length and spliced transcripts. Transcript A1 encodes a retroviral cyclin (rv-cyclin) with limited homology to host cyclins. The rv-cyclin is physically linked to components of the transcriptional co-activator complex, Mediator, and regulates transcription. In walleye fibroblasts, it inhibits the WDSV promoter independently of cis-acting DNA sequences. The rv-cyclin activates transcription from GAL4 promoters when fused to the GAL4 DNA binding domain. A 30 a.a. activation domain in the carboxy region can be inactivated by single point mutations, and these mutations diminish the ability of the rv-cyclin to inhibit the WDSV promoter. When fused to glutathione S-transferase, the rv-cyclin, its carboxy region, and the activation domain pull down components of transcription complexes from nuclear extracts, and pulldown is lost by mutation of the activation domain.
Broad range purity analysis by melting point depression using a singular feature common to all DSC purity scans

Abstract DSC purity assay by melting point between has had a limited range of less than several percent impurities. Step-mode heating techniques have increased the range to 6–8%. However, empirical corrections were used to linearize the purity slope of the van't Hoff plot, temperatures vs. reciprocal of fraction melted (1/ F ). A unique feature common to all dynamic purity scans has been discovered which matches a point on the non-linear van't Hoff plot to the heating rate. This point, or reciprocal of the melt fraction (1/ F ), occurs where the melting rate has attained maximum acceleration. The melting rate at this point is used as a tangential straight line projection from the curve to become a function of mole % impurity. The melting rate at maximum acceleration is independent of reference material, heating rate, sample size, thermal conductivity, or specific heat. Phenacetin, spiked with 50 mole % benzamide, has been measured to ±2 mole % at heating rate of 5 and 10°C min −1 ; the restriction on upper detection limits is adequate resolution between preliminary eutectic events and the final melt. Impurities in indium, with a reported purity of 99.9999%, have been measured at 4 × 10 −5 mole % by this technique.
Gamma knife stereotactic radiosurgery for salivary gland neoplasms with base of skull invasion following neutron radiotherapy

Background. Our aim was to examine the outcome of patients treated with a planned gamma knife boost after completion of neutron radiotherapy for salivary gland neoplasms involving the base of skull. Methods. Thirty-four patients with salivary gland neoplasms involving the base of skull were treated from 2001 to 2005 at our institution. These results were compared with a similar historical group treated at our institution from 1984 to 2000. The patients had the following characteristics: median age: 54 years (range, 23–80); median follow-up period: 20.5 months (range, 4–55); women-to-men patient ratio: 1.1:1; histology: 29 adenoid cystic, 3 adenocarcinoma, 1 acinic cell, 1 mucoepidermoid; primary sites of disease: 6 nasopharyngeal, 14 paranasal sinuses, 4 parotid gland, 8 oral cavity, 1 lacrimal gland, and 1 auditory canal. All patients had gross residual disease at the time of treatment. The median neutron dose prescribed to isocenter was 19.2 nGy and the median dose to the effected temporal tip was 11.98 nGy. The median prescribed gamma knife dose was 12 Gy to the 50% isodose line. The median number of isocenters was 17. The median target volume treated was 12.4 cm3 (range, 1.9–28.9) with a median total volume treated of 18.3 cm3 (range, 5.9–53.9). Results. The 24-month and 40-month Kaplan–Meier estimated local control was 82% versus 81% (24 months) and 82% versus 39% (40 months; p = .04) for the gamma knife treated group versus historical controls (n = 61). Two of the 4 failures in the gamma knife–treated group occurred outside the boosted area. Complications were no greater in the gamma knife–treated group than in those treated with neutron radiotherapy alone. Conclusions. Patients with primary salivary gland neoplasms that involve the base of skull and are treated with neutron radiotherapy alone are at high risk of local recurrence. A gamma knife boost improves local control and adds little additional toxicity. These preliminary results suggest that all patients with salivary neoplasms and base of skull invasion should be considered for a gamma knife boost after primary treatment with neutron radiotherapy. © 2007 Wiley Periodicals, Inc. Head Neck, 2008