cssi/SciSciGPT-SciSciNet huggingface dataset:
Cardio-oncology Care in the Time of COVID-19 and the Role of Telehealth.

In the last few months, the world has been swept by coronavirus disease-19 (COVID-19), a disease caused by the severe acute respiratory syndrome coronavirus-2 that can lead to fatal acute respiratory distress syndrome, cardiomyopathy, and arrhythmias. We have quickly learned that patients with pre-
Does Climate Protest Work? Partisanship, Protest, and Sentiment Pools:

This study demonstrates whether and how climate protest increases or decreases the “sentiment pools” available to the climate movement. Using an experimental vignette survey design (n = 1,421), the...
The interplay between non-esterified fatty acids and bovine peroxisome proliferator-activated receptors: results of an in vitro hybrid approach.

In dairy cows circulating non-esterified fatty acids (NEFA) increase early post-partum while liver and other tissues undergo adaptation to greater lipid metabolism, mainly regulated by peroxisome proliferator-activated receptors (PPAR). PPAR are activated by fatty acids (FA), but it remains to be demonstrated that circulating NEFA or dietary FA activate bovine PPAR. We hypothesized that circulating NEFA and dietary FA activate PPAR in dairy cows. The dose-response activation of PPAR by NEFA or dietary FA was assessed using HP300e digital dispenser and luciferase reporter in several bovine cell types. Cells were treated with blood plasma isolated from Jersey cows before and after parturition, NEFA isolated from the blood plasma, FA released from lipoproteins using milk lipoprotein lipase (LPL), and palmitic acid (C16:0). Effect on each PPAR isotype was assessed using specific synthetic inhibitors. NEFA isolated from blood serum activate PPAR linearly up to ~ 4-fold at 400 μmol/L in MAC-T cells but had cytotoxic effect. Addition of albumin to the culture media decreases cytotoxic effects of NEFA but also PPAR activation by ~ 2-fold. Treating cells with serum from peripartum cows reveals that much of the PPAR activation can be explained by the amount of NEFA in the serum (R2 = 0.91) and that the response to serum NEFA follows a quadratic tendency, with peak activation around 1.4 mmol/L. Analysis of PPAR activation by serum in MAC-T, BFH-12 and BPAEC cells revealed that most of the activation is explained by the activity of PPARδ and PPARγ, but not PPARα. Palmitic acid activated PPAR when added in culture media or blood serum but the activation was limited to PPARδ and PPARα and the response was nil in serum from post-partum cows. The addition of LPL to the serum increased > 1.5-fold PPAR activation. Our results support dose-dependent activation of PPAR by circulating NEFA in bovine, specifically δ and γ isotypes. Data also support the possibility of increasing PPAR activation by dietary FA; however, this nutrigenomics approach maybe only effective in pre-partum but not post-partum cows.
Comparative analysis of corolla tube development across three closely related Mimulus species with different pollination syndromes.

Fusion of petals to form a corolla tube is considered a key innovation contributing to the diversification of many flowering plant lineages. Corolla tube length often varies dramatically among species and is a major determinant of pollinator preference. However, our understanding of the developmental dynamics underlying corolla tube length variation is very limited. Here we examined corolla tube growth in the Mimulus lewisii species complex, an emerging model system for studying the developmental genetics and evo-devo of pollinator-associated floral traits. We compared developmental and cellular processes associated with corolla tube length variation among the bee-pollinated M. lewisii, the hummingbird-pollinated Mimulus verbenaceus, and the self-pollinated Mimulus parishii. We found that in all three species, cell size is non-uniformly distributed along the mature tube, with the longest cells just distal to the stamen insertion site. Differences in corolla tube length among the three species are not associated with processes of organogenesis or early development but are associated with variation in multiple processes occurring later in development, including the location and duration of cell division and cell elongation. The tube growth curves of the small-flowered M. parishii and large-flowered M. lewisii are essentially indistinguishable, except that M. parishii tubes stop growing earlier at a smaller size, suggesting a critical role of heterochrony in the shift from outcrossing to selfing. These results not only highlight the developmental process associated with corolla tube variation among species but also provide a baseline reference for future developmental genetic analyses of mutants or transgenic plants with altered corolla tube morphology in this emerging model system.
e-ASPECTS software improves interobserver agreement and accuracy of interpretation of aspects score:

IntroductionThere is increased interest in the use of artificial intelligence-based (AI) software packages in the evaluation of neuroimaging studies for acute ischemic stroke. We studied whether, c...
Reconstructing co-dependent cellular crosstalk in lung adenocarcinoma using REMI

Abstract Cellular crosstalk in tissue microenvironments is fundamental to normal and pathological biological processes. Global assessment of cell-cell interactions (CCI) is not yet technically feasible, but computational efforts to reconstruct these interactions have been proposed. Current computational approaches that identify CCI often make the simplifying assumption that pairwise interactions are independent of one another, which can lead to reduced accuracy. We present REMI (REgularized Microenvironment Interactome), a graph-based algorithm that predicts ligand-receptor (LR) interactions by accounting for LR dependencies on high-dimensional, small sample size datasets. We apply REMI to reconstruct the human lung adenocarcinoma (LUAD) interactome from a bulk flow-sorted RNA-seq dataset, then leverage single-cell transcriptomics data to increase its resolution and identify LR prognostic signatures. We experimentally confirmed colocalization of CTGF:LRP6 as an interaction predicted to be associated with LUAD progression. Our work presents a novel way to reconstruct interactomes and a new approach to identify clinically-relevant cell-cell interactions.
Trends in prevalence of extended-spectrum beta-lactamase-producing Escherichia coli isolated from patients with community- and healthcare-associated bacteriuria: results from 2014 to 2020 in an urban safety-net healthcare system

Author(s): Raphael, Eva; Glymour, M Maria; Chambers, Henry F | Abstract: BackgroundThe prevalence of infections caused by extended-spectrum beta-lactamase producing Escherichia coli (ESBL-E. coli) is increasing worldwide, but the setting in which this increase is occurring is not well defined. We compared trends and risk factors for ESBL-E. coli bacteriuria in community vs healthcare settings.MethodsWe collected electronic health record data on all patients with E. coli isolated from urine cultures in a safety-net public healthcare system from January 2014 to March 2020. All analyses were stratified by healthcare-onset/associated (bacteriuria diagnosed g 48nh after hospital admission or in an individual hospitalized in the past 90ndays or in a skilled nursing facility resident, N = 1277) or community-onset bacteriuria (bacteriuria diagnosed l 48nh after hospital admission or in an individual seen in outpatient clinical settings without a hospitalization in the past 90ndays, N = 7751). We estimated marginal trends from logistic regressions to evaluate annual change in prevalence of ESBL-E. coli bacteriuria among all bacteriuria. We evaluated risk factors using logistic regression models.ResultsESBL-E. coli prevalence increased in both community-onset (0.91% per year, 95% CI 0.56%, 1.26%) and healthcare-onset/associated (2.31% per year, CI 1.01%, 3.62%) bacteriuria. In multivariate analyses, age g 65 (RR 1.88, CI 1.17, 3.05), male gender (RR 2.12, CI 1.65, 2.73), and Latinx race/ethnicity (RR 1.52, CI 0.99, 2.33) were associated with community-onset ESBL-E. coli. Only male gender (RR 1.53, CI 1.03, 2.26) was associated with healthcare-onset/associated ESBL-E. coli.ConclusionsESBL-E. coli bacteriuria frequency increased at a faster rate in healthcare-associated settings than in the community between 2014 and 2020. Male gender was associated with ESBL-E. coli bacteriuria in both settings, but additional risks-age g 65 and Latinx race/ethnicity-were observed only in the community.
Universal Design as an Approach to Technology Intervention for Seniors

Typical design approaches for technology interventions for seniors tends to focus on specialized design to accommodate functional limitations associated with either disability or aging. This paper will propose universal design as an alternative approach that focuses on design for all users, regardless of age or ability. Moreover, while specialized design is based on prescriptive requirements that often dictate what to design, universal design is an approach to technology intervention that is guided by a set of performance principles and guidelines that provide a rationale for how to design technologies. As such, universal design as extends the usability of everyday design to seniors, without the need for special adaptations or devices.
Vitamin E analogs as radiation response modifiers

The potentially life-threatening effects of total body ionizing radiation exposure have been known for more than a century. Despite considerable advances in our understanding of the effects of radiation over the past six decades, efforts to identify effective radiation countermeasures for use in case of a radiological/nuclear emergency have been largely unsuccessful. Vitamin E is known to have antioxidant properties capable of scavenging free radicals, which have critical roles in radiation injuries. Tocopherols and tocotrienols, vitamin E analogs together known as tocols, have shown promise as radioprotectors. Although the pivotal mechanisms of action of tocols have long been thought to be their antioxidant properties and free radical scavenging activities, other alternative mechanisms have been proposed to drive their activity as radioprotectors. Here we provide a brief overview of the effects of ionizing radiation, the mechanistic mediators of radiation-induced damage, and the need for radiation countermeasures. We further outline the role for, efficacy of, and mechanisms of action of tocols as radioprotectors, and we compare and contrast their efficacy and mode of action with that of another well-studied chemical radioprotector, amifostine.
Perception-Based Navigation for Mobile Robots

Ongoing research on multi-robot collaborative navigation conducted in the Intelligent Robotics Lab at Vanderbilt University is introduced. Range-free egocentric representations for navigation have been previously devieloped for a single robot. We refer to this method as perception-based navigation (PBN). This paper will show that the concept of PBN can be extended from a single robot to a group of robots to achieve collaborative navigation. One robot attempts to reach a target region by sharing its sensory information with the knowledge of another. PBN approach separates sensing and navigation from planning. Our assumption is that one robot is lost or new in an environment, which is known to another robot. The new robot asks for assistance by presenting its egocentric world perceptions. We show the PBN idea is expandable to handle collaborative efforts to achieve a goal.
Samuel Johnson: A Biography – By Peter Martin

This author's lucid, engaging, and humane book navigates the Scylla and Charybdis menacing Samuel Johnson's biographers. On one side squats the crowdedness of the field. On the other churns the cal...
Detecting soil disturbance/restoration effects on stream sediment loading in the Lake Tahoe Basin, USA-modelling predictions

Establishment and ‘crediting’ for total maximum daily loads (TMDL) of sediment require development of stream monitoring programs capable of detecting changes in land use and erosion ‘connectivity’ conditions across the watershed. As a ‘proof of concept’ directed at developing such an effective stream monitoring program considering only the effects of soil disturbances or restoration in the Lake Tahoe Basin, variability in daily stream sediment load predictions from a local-scale, field data–based distributed runoff and erosion model developed previously is analysed for the west-shore watersheds of Homewood (HMR) and Madden Creeks. The areal extent effects of forest fuel reductions (slight soil disturbances in Madden) and soil restoration efforts (e.g. dirt road removal and ski-run rehabilitation in HMR) on watershed daily sediment loads for the 1994–2005 period are considered. Based on model predictions, forest fuel management in the Madden Creek watershed must occur across more than 30% of the basin area to result in a detectable increase in daily sediment loads at the >95% confidence level. Similarly, a daily load reduction that could be assessed with >95% confidence within the HMR basin required substantial dirt road removal (50% by roaded area) and restoration of 20% of the ski-run area (combined for ~5% of the basin area) for the 11-year record but was also possible within 2–3 years following restoration. These modelling results suggest that despite considerable flow–load variability, it may be possible to detect cumulative changing land-use conditions within several years of project completion such that quantitative TMDL ‘crediting’ may be developed. Copyright © 2012 John Wiley & Sons, Ltd.
Postoperative care following pituitary surgery

Patients undergoing surgery for pituitary tumors represent a heterogeneous population each with unique clinical, biochemical, radiologic, pathologic, neurologic, and/or ophthalmologic considerations. The postoperative management of patients following pituitary surgery often occurs in the context of a dynamic state of the hypothalamic-pituitary-end organ axis. Consequently, a significant component of the postoperative care of these patients focuses on vigilant screening and observation for neuroendocrinologic perturbations such as varying degrees of hypopituitarism and disorders of water balance (diabetes insipidus and the syndrome of inappropriate antidiuretic hormone). Additionally, one must be cognizant of other potential complications specific to the transsphenoidal approach for tumor removal including cerebrospinal fluid leakage and meningitis. This review addresses the postoperative management of patients undergoing pituitary surgery with an emphasis on careful screening and recognition of complications.
Investigations on the reaction of azide with sperm whale ferrimyoglobin

Abstract Spectrophotometric equilibrium experiments on sperm whale ferrimyoglobin were conducted at various temperatures and pH values, and in the presence of sodium azide. Enthalpy changes (10–15 kcal/mole) were derivable from results on the azide complex at pH 5.0 and 6.0. Anaerobic conditions are needed for experiments at low pH values: a slow decrease in the 419-nm band for MetMbN 3 was observed at pH 5 under aerobic conditions. Difference spectra for the complex and the basic form of ferrimyoglobin (reference is ferrimyoglobin at pH 6.0) show striking similarities, pointing to corresponding structural similarities between the two compounds. It is concluded that the protonation of azide more likely determines the pH-dependence of the two rate constants (pH ≳ 7) than some protonation of ferrimyoglobin. The proton dissociation of ferrimyoglobin, associated with p K H = 8.9, is very fast, but seems to represent just one single step, as far as can be deduced from equilibrium signal changes obtained from temperature jump experiments.
Statistical analysis of travel-time anomalies

Abstract We develop a method of testing local travel-time data for the presence of velocity anomalies. Using the theory of statistical hypothesis testing, we compare residual errors from two different models, one normal and one containing an anomaly. The probability of a false rejection is estimated, and is used to accept or reject the normal hypothesis. Application of the method to aftershocks of the 1975 Oroville, California earthquake illustrates the problems that are caused by incomplete knowledge of the local time-independent structure.
Development of CNT paste for high-current density field emitters

In this study, we have developed a CNT paste for high-current density field emitters by using a ball-milling process. The ball-milling was used in the CNT paste procedure for effective material dispersion. Material dispersion is one of the most important factors in a paste synthetic process. The ball-milling is a very easy and simple method to produce a printable CNT paste. The CNT paste was made of only a few materials, such as thin multi-walled CNTs (4-6 nm dia.), a nano metal powder (<; 100 nm dia.), an organic powder and a solvent. To form field emitters, the ball-milled CNT paste was printed on the Kovar metal sheet as a cathode plate by using a screen-printing method. The printed CNT paste was fired in the air condition and then the surface treatment was carried out to the printed CNTs. Fig. 1 shows SEM images of the CNT emitter on Kovar metal sheet. The fabricated CNT emitters were vertical-aligned well and had clean surface with little residue.
A method to predict an average activation energy for subassemblies

The problem of predicting an average acceleration effect under the Arrhenius model of a subassembly with known operating and stress conditions is addressed. The average effect includes the several failure mechanisms that can exist along with the several stress conditions across the product associated with unique temperature profiles. The averaging effect is modeled by predicting an average activation energy. An example is included to demonstrate the ease of the computation. >
Sampling animal sign in heterogeneous environments: How much is enough?

Abstract Animal ecologists often use animal sign as a surrogate for direct observation of organisms, especially when species are secretive or difficult to observe. Spatial heterogeneity in arid environments makes it challenging to consistently detect and precisely characterize animal sign, which can bias estimates of animal abundance or habitat use. Piute ground squirrels ( Urocitellus mollis ) and Owyhee harvester ants ( Pogonomyrmex salinus ) live in arid environments and are fossorial, which can make them difficult to observe directly. Their relative abundance can be assessed using sign (i.e., burrows and nests). We implemented an over-sampling framework (i.e., recorded an excessive amount of information) with two observers to 1) identify a sampling intensity that balanced precision with our resource constraints, and 2) assess classification and detection of squirrel burrows and ant nests across vegetation conditions. We sampled 20 1-ha plots for ground squirrel burrows and ant nests using six 4 m × 100 m belt transects. Analyses of precision and sampling effort indicated that three belt transects covering 1200 m 2 per ha provided sufficient precision, while minimizing effort. Regardless of vegetation conditions, counts by two observers were strongly correlated for ground squirrel burrows ( r = 0.99, P r = 0.99, P
Sulfate addition increases methylmercury production in an experimental wetland.

Atmospheric mercury is the dominant Hg source to fish in northern Minnesota and elsewhere. However, atmospherically derived Hg must be methylated prior to accumulating in fish. Sulfate-reducing bacteria are thought to be the primary methylators of Hg in the environment. Previous laboratory and field mesocosm studies have demonstrated an increase in methylmercury (MeHg) levels in sediment and peatland porewaters following additions of sulfate. In the current ecosystem-scale study, sulfate was added to half of an experimental wetland at the Marcell Experimental Forest located in northeastern Minnesota, increasing annual sulfate load by approximately four times relative to the control half of the wetland. Sulfate was added on four separate occasions during 2002 and delivered via a sprinkler system constructed on the southeast half (1.0 ha) of the S6 experimental wetland. MeHg levels were monitored in porewater and in outflow from the wetland. Prior to the first sulfate addition, MeHg concentrations (filtered...
Model Discrimination Using Data Collaboration

This paper introduces a practical data-driven method to discriminate among large-scale kinetic reaction models. The approach centers around a computable measure of model/data mismatch. We introduce two provably convergent algorithms that were developed to accommodate large ranges of uncertainty in the model parameters. The algorithms are demonstrated on a simple toy example and a methane combustion model with more than 100 uncertain parameters. They are subsequently used to discriminate between two models for a contemporarily studied biological signaling network.
Trends in reporting methadone-associated cardiac arrhythmia, 1997-2011: an analysis of registry data.

Methadone is a long-acting synthetic opioid agonist prescribed in the United States for chronic pain and opioid dependency, and its use has increased by more than 500% in the past decade compared with the previous decade (1, 2). Methadone has been implicated in 30% to 40% of opioid-related deaths despite representing a minority of opioid prescriptions, and the mortality rate associated with it is substantially greater per morphine milligram equivalent than all other prescription opioids (1-5). Because drugs are now the second-leading cause of accidental death in U.S. adults and 40% are attributable to opioids (2), the U.S. Food and Drug Administration (FDA) convened a joint meeting of the Anesthetic and Life Support Drugs Advisory Committee and the Drug Safety and Risk Management Advisory Committee in 2010 to discuss a risk evaluation and mitigation strategy (REMS) (1). Although opioid-related death is generally attributed to respiratory depression from overdose, methadone has been associated with QTc interval prolongation and torsade de pointes. Because of the disproportionate mortality rate of methadone compared with other opioids and the long elimination half-life (8 to 130 hours) and QTc-prolonging properties of methadone, a separate REMS for methadone was considered. However, the FDA ultimately adopted a single REMS for all long-acting opioids that did not outline strategies to reduce arrhythmia risk (1, 6). An association between methadone and torsade de pointes was first described in 2002 (7) and subsequently found to be mediated by a blockade of the human Ether-a-go-go ion channel responsible for the delayed rectifier potassium current (8). A boxed warning was added to FDA labeling for methadone in 2006 about arrhythmia risk (9), followed by a clinical practice guideline in 2009 recommending QTc interval screening (10). Universal adoption of a cardiac safety program was recently recommended for all U.S. opioid treatment programs by the Substance Abuse and Mental Health Services Administration, but the need for QTc interval screening remained controversial (11). Debate about which strategies should be used to mitigate the increasing mortality rates associated with prescription opioids continues (12-14), and some have argued that QTc interval screening for methadone is unnecessary (15, 16). This lack of consensus is reflected in the limited use of opioid risk-reduction strategies, even among high-risk patients in primary care (17). Given uncertainty about the clinical relevance of QTc prolongation and the frequency of arrhythmia events, we evaluated the FDA Adverse Event Reporting System (FAERS) database for a signal of disproportionate reporting of QTc prolongation or torsade de pointes associated with methadone relative to other opioids and antiarrhythmic drugs. We also examined whether methadone associated arrhythmia reports have increased after the initial publication of the association between methadone and torsade de pointes.
Protein Denaturation during Freezing and Thawing in Phosphate Buffer Systems: Monomeric and Tetrameric β-Galactosidase

During freezing in sodium and potassium phosphate (NaP and KP) buffer solutions, changes in pH may impact the stability of proteins. Since the degradation pathways for the model proteins, monomeric and tetrameric beta-galactosidase (beta-gal), chosen for this study are governed by conformational changes (i.e., physical instability) as opposed to chemical transformations, we explored how the stresses of freezing and thawing alter the protein's native structure and if preservation of the native conformation during freeze-thawing is a requisite for optimal recovery of activity. During freezing in NaP buffer, a significant pH decrease from 7.0 to as low as 3.8 was observed due to the selective precipitation of the disodium phosphate; however, the pH during freezing in KP buffer only increased by at most 0.3 pH units. pH-induced inactivation was evident as seen by the lower recovery of activity when freeze-thawing in NaP buffer as compared to KP buffer for both sources of beta-gal. In addition, we investigated the effects of cooling rate and warming rate on the recovery of activity for monomeric and tetrameric beta-gal. Optimal recovery of activity for the NaP samples was obtained when the processing protocol involved a fast cool/fast warm combination, which minimizes exposure to acidic conditions and concentrated solutes. Alterations in the native secondary structure of monomeric beta-gal as measured by infrared spectroscopy were more significant when freezing and thawing in NaP buffer as opposed to KP buffer. Conformational and activity analyses indicate that pH changes during freezing in NaP buffer contribute to denaturation of beta-gal. These results suggest that proteins formulated in NaP buffer should be frozen and thawed rapidly to minimize exposure to low pH and high buffer salts.
Molecular-dynamics study of the reconstructed Au(111) surface: Low temperature.

We study the stability and dynamics on the reconstructed Au(111) surface using three-dimensional molecular-dynamics simulations. The small-amplitude surface-phonon dispersions are calculated along the 〈110〉 direction and compared with inelastic-He-scattering data. The agreement with the experimental data is remarkable, given that the parameters of the surface interatomic potentials are chosen solely to reproduce the size and type of the observed surface dislocations. Low-lying localized modes (soliton modes) appear in all three polarizations and localized modes with polarization in the sagittal plane are observed around the K point with energies of about 8 meV.
Se-modified Ru nanoparticles as ORR catalysts – Part 1: Synthesis and analysis by RRDE and in PEFCs

Abstract We report a new method of preparation of a methanol-tolerant Se/Ru cathode catalyst for the direct methanol fuel cell (DMFC) [1,2] , whereby selenium is deposited on ruthenium nanoparticles by H 2 -reduction of SeO 2 in aqueous solution at room temperature. The obtained Se/Ru(aq) was studied by electrochemical measurements and tested as a cathode catalyst in H 2 –air and direct methanol fuel cells. The new catalyst formulation (Se/Ru(aq)) is shown to be superior to Se/Ru synthesized from xylenes solvent [3] and to Ru black by RRDE measurements, in terms of both activity and selectivity for complete oxygen reduction to water. Although Ru black is less active, the Tafel slopes and activation energies of Se/Ru catalysts and reduced-Ru black are similar, implying similar ORR mechanisms. In H 2 –air fuel cell tests, Se/Ru(aq) was more active than Se/Ru(xyl) at all voltages. Compared to Ru black, Se/Ru(aq) was superior at low current densities, but Ru black slightly exceeded the performance of Se/Ru at high current densities. To explain the RRDE and fuel cell observations, the two roles of Se as an inhibitor of Ru oxidation and as a site-blocker are discussed.
Proximal chiral phase transition.

We consider the form of the chiral-symmetry-breaking piece of the effective potential in the linear \ensuremath{\sigma} model. Surprisingly, it allows for a second local minimum at both zero and finite temperatures. Even though chiral symmetry is not exact, and therefore is not restored in a true phase transition at finite temperature, this second minimum can nevertheless mimic many of the effects of a first-order phase transition. We derive a lower limit on the height of the second minimum relative to the global minimum based on cosmological considerations; this limit is so weak as to be practically nonexistent. In high energy nuclear collisions, it may lead to observable effects in Bose-Einstein interferometry due to domain walls and to coherent pion emission.
The convergence of the effective shell-model interaction in the sd-shell☆

Abstract The results of an exact shell-model calculation for 18 O by Lo Iudice, Rowe and Wong are compared with those obtained with a perturbation expansion for the effective shell-model interaction complete through third order. The comparison suggests a converging expansion. The importance of folded diagrams in third order is demonstrated.
Atrioventricular Nodal Function in the Immature Canine Heart

ABSTRACT. Previous studies have suggested that the atrioventricular nodal functional refractory period in the neonate is equal to or shorter than that of the ventricle, providing little or no protection to the ventricle against rapid atrial rates and allowing closely coupled atrial beats to fall within the ventricular vulnerable period. We evaluated atrioventricular node function in 21 mongrel neonatal puppies, 3–15 days old, and 15 adult dogs utilizing intracardiac His bundle recording and stimulation techniques. The mean atrioventricular nodal functional refractory period (173.1 ± 20.0 ms) exceeded both the ventricular effective refractory period (139.5 ± 14.3) and ventricular functional refractory period (163.3 ± 14.5) in the neonates. Furthermore, the atrioventricular node was the site of limiting antegrade conduction in all neonates. No ventricular arrhythmias were induced by atrial extrastimulation in any of the neonates. The site of conduction delay during atrial extrastimulation was confined to the atrioventricular node in 15/16 neonates (94%) while 1/16 (6%) had combined nodal and infranodal delay. The neonates developed Wenckebach, at significantly faster heart rates than the adults, but both groups developed Wenckebach at approximately twice the resting heart rate. Retrograde conduction was a consistent finding in the neonates. However, antegrade Wenckebach occurred at a significantly faster heart rate than retrograde Wenckebach suggesting different functional properties. Our data suggest that in the neonatal canine, the atrioventricular node functional refractory period is longer than both the ventricular effective refractory period and ventricular functional refractory period. Furthermore, the degree of protection offered by the neonatal atrioventricular node to the ventricle appears to be comparable to that of the adult.
Control and verification of high-dimensional systems with DSOS and SDSOS programming

In this paper, we consider linear programming (LP) and second order cone programming (SOCP) based alternatives to sum of squares (SOS) programming and apply this framework to high-dimensional problems arising in control applications. Despite the wide acceptance of SOS programming in the control and optimization communities, scalability has been a key challenge due to its reliance on semidefinite programming (SDP) as its main computational engine. While SDPs have many appealing features, current SDP solvers do not approach the scalability or numerical maturity of LP and SOCP solvers. Our approach is based on the recent work of Ahmadi and Majumdar [1], which replaces the positive semidefiniteness constraint inherent in the SOS approach with stronger conditions based on diagonal dominance and scaled diagonal dominance. This leads to the DSOS and SDSOS cones of polynomials, which can be optimized over using LP and SOCP respectively. We demonstrate this approach on four high dimensional control problems that are currently well beyond the reach of SOS programming: computing a region of attraction for a 22 dimensional system, analysis of a 50 node network of oscillators, searching for degree 3 controllers and degree 8 Lyapunov functions for an Acrobot system (with the resulting controller validated on a hardware platform), and a balancing controller for a 30 state and 14 control input model of the ATLAS humanoid robot. While there is additional conservatism introduced by our approach, extensive numerical experiments on smaller instances of our problems demonstrate that this conservatism can be small compared to SOS programming.
RNA polymerase-cNMP-ligated cAMP receptor protein (CRP) mutant interactions in the enhancement of transcription by CRP mutants.

Abstract The enhancement of the transcription of three synthetic promoters by cNMP-ligated cAMP receptor protein (CRP)/mutant complexes was determined from the transcription yields of a short AAUU transcript in an abortive initiation in vitro transcription assay. The cNMP-ligated CRP and mutants were cAMP, cGMP, and cIMP ligated with CRP, T127L CRP, S128A CRP, and T127L/S128A CRP. The transcriptional activation of a 152-base pair lacUV5promoter (synlac promoter) with a CRP consensus binding site sequence (syncon promoter) was enhanced by an average factor of 12.3 ± 0.5 with the cAMP-ligated complexes of CRP/mutants and cGMP-ligated T127L, although their promoter binding site affinities varied by a factor of 5. However, in the presence of bound RNA polymerase, the binding affinities only ranged from 0.8 ± 0.2 × 107 m − 1for cAMP-ligated CRP* to 1.8 ± 0.3 × 107 m − 1 for cAMP-ligated CRP, indicating that the CRP/mutant interacts with the bound RNA polymerase, which would account for the near constancy of the enhancement factors. The corresponding enhancement factors for the synlacpromoter and a promoter with a different CRP binding site sequence (syngal promoter) were also nearly the same, 7.2 ± 0.7 and 6 ± 1, respectively. The binding reaction of thesyncon promoter to the RNA polymerase is exothermic, with a binding constant (K b) = 2.1 ± 0.2 × 107 m −1.
Differential Scanning Calorimetry of Forest Fuels

Previous investigations for developing fire spread models in wildland forest fuels have not adequately assessed the heat-sink characteristics of the different fuels. This research uses differential scanning calorimetry to determine the total heat required to change the temperature of a sample of forest fuel from 25/sup 0/ to 500/sup 0/C. The incremental heat input is recorded for 10/sup 0/C increments. Thermogravimetric analysis data are given for equivalent samples. Significant differences are noted between major fuels in the total heat required at 500/sup 0/C. Generally, the heat required for pyrolysis of these fuels is as important as that for evaporating moisture from the fuel.
The influence of photometer design on optical-conformational changes.

Abstract When cells and large subcellular structures suffer a change in volume or internal structure, their light-scattering properties are normally altered. These optical-conformation changes are potential sources of information about conformation and processes which alter it. Classical light-scattering theory for spherical particles is used to determine how the transmittance or extinction of a cell suspension should respond when such a conformational change occurs and the measurements are made with a conventional photometer. This extends an earlier study of transmittances measured with an “ideal” photometer. The photocell of an ideal instrument collects only the directly transmitted light. In a conventional instrument it also collects the light scattered at small angles, which is usually most of the scattered light. Extinction (optical density, absorbance) of suspensions of spherical cells was computed for several photometer designs. It is found that γ, the angle of acceptance of the photocell, has a significant influence on the extent and even the nature of the photometric response to a given conformational change. Earlier, it was shown that a decrease in cell volume or increase in internal structure will increase extinction for cells of many sizes. Now it is found that a large γ-value increases these effects. An approach to the interpretation of transmitted light fluxes in terms of theoretical predictions is outlined.
The last book

In this paper we describe our efforts at the Massachusetts Institute of Technology Media Laboratory toward realizing an electronic book comprised of hundreds of electronically addressable display pages printed on real paper substrates. Such pages may be typeset in situ, thus giving such a book the capability to be any book. We outline the technology we are developing to bring this about and describe a number of applications that such a device enables.
Adjuvant treatment of elderly breast cancer patients

Increasing age is the major risk factor for breast cancer. About half of all new breast cancers and more than half of breast cancer deaths in affluent nations occur in women 65 years and older. Endocrine therapy with aromatase inhibitors or tamoxifen is appropriate adjuvant therapy for older women with life expectancies of greater than 5 years and hormone receptor positive tumors. The greatest benefit of adjuvant chemotherapy is in elders with hormone receptor negative, node positive, or high-risk node negative tumors. The effect of co-morbidity on survival must be factored into all adjuvant therapy decisions and newer validated tools can accurately estimate non-breast cancer related survival. Age bias still exists and results in frequent undertreatment of older women and compromised survival. Elders remain under-represented in clinical trials and should be encouraged to participate. Health care providers as well as government leaders and patients need to be educated on cancer in elders.
Eliminating Special Education: Is This the Solution?

Stephens critically examines Pugach's ideas regarding the relationship be tween special and regular education. Further, he reviews the social and economic history that, until recently, denied a free and appropriate education to many handicapped children. It was because of the public schools' failure to meet the educational needs of children with exceptionalities that special school programs and related teacher prepara tion programs were created. Eight of Pugach's assertions are addressed in this rejoinder.
The utility of seat belt signs to predict intra-abdominal injury following motor vehicle crashes.

Objective: Safety belts are the most important safety system in motor vehicles and should always be worn to prevent serious injury. The purpose of this study, using Crash Injury Research Engineering Network (CIREN) data, was to assess occupant and crash factors associated with minor contusions and abrasions caused by the safety belt (commonly referred to as seat belt signs) and their association with serious intra-abdominal trauma. Methods: CIREN data were used to determine which factors are associated with seat belt signs. Occupant variables (age, gender, body mass index, proper safety belt use, driver v. passenger status) and crash variables (crash type, crash severity, and airbag deployment) were compared for occupants with seat belt sign who had serious (AIS 3 or greater) intra-abdominal injury and those who did not have intra-abdominal injuries. Adjusted odds ratios were used to quantify the independent association between predictive factors for serious intra-abdominal injury for occupants with seat ...
Free Radical Theory of Aging: Effect of Age, Sex and Dietary Precursors on Rat-Brain Docosahexanoic Acid†

Increasing the peroxidizability of dietary fat has an adverse effect on the function of the central nervous system (CNS) in the rat. This effect may be influenced by the level of docosahexanoic acid, a highly unsaturated fatty acid, selectively concentrated in the phospholipids of brain membranes. This study was aimed at determining the influence of age, sex, and the nature of a dietary lipid supplement - linolenic acid (18:3w3), docosahexanoic acid (22:6w3), or the same amount of 22:6w3 in the form of menhaden oil triglycerides - on the rate of increase in the percentage of 22:6w3 in the whole-brain fatty acids of rats between the ages of 1 and 12 months. The dietary lipid supplements were reflected in linear increases in the brain 22:6w3 of female rats throughout the study. Between 6 and 12 months of age, the rate of incorporation of dietary 22:6w3 and its precursors into the brain 22:6w3 of male rats dropped. At 12 months it was about half that for females in the case of 22:6w3 and menhaden oil, and about zero for 18:3w3. It is suggested that dietary 22:6w3 and its precursors may modify CNS function by altering membrane function and peroxidizability through changes in the concentration of 22:6w3 in membrane phospholipids.
Open runtime platform: flexibility with performance using interfaces

According to conventional wisdom, interfaces provide flexibility at the cost of performance. Most high-performance Java virtual machines today tightly integrate their core virtual machines with their just-in-time compilers and garbage collectors to get the best performance. The Open Runtime Platform (ORP) is unusual in that it reconciles high performance with the extensive use of well-defined interfaces between its components. ORP was developed to support experiments in dynamic compilation, garbage collection, synchronization, and other technologies. To achieve this, two key interfaces were designed: one for garbage collection and another for just-in-time compilation. This paper describes some interesting features of these interfaces and discusses lessons learned in their use. One lesson we learned was to selectively expose small but frequently accessed data structures in our interfaces; this improves performance while minimizing the number of interface crossings.
Genetic screens and selections for small molecules based on a synthetic riboswitch that activates protein translation.

Genetic selection provides the most powerful method to assay large libraries of biomolecules for function. However, harnessing the power of genetic selection for the detection of specific, nonendog...
Additive variance and average effect with partial selfing.

The covariance of an ancestor and the average of its descendants in generation t(C Pt ) is formulated for a breeding system which is a mixture of selfing and outcrossing. This covariance is partitioned into least squares additive (σ A. At ) and non-additive (σ D. Dt ) components summed over individual loci, and the combined inbreeding effects of all loci ( H ′), such that C Pt = σ A. At + ( s /2) t [σ D. Do + H ′]. For the m th locus the covariance m σ A. At = 2(1 + F )Σ i p i α (0) i α ( t ) i , in which p i is the frequency of the i th allele whose additive effect (α ( t ) ) depends on the generation for which it is defined. For distant descendants α (∞) is equal to half of the derivative of the population mean with respect to the frequency of the allele. The covariance C P ∞ = σ A. A ∞ thus relates directly to permanent selection response measured in the equilibrium population, any additional responses observed in earlier generations being due to temporary disturbances in population genotypic structure. It is only for these distant descendants that the least squares additive component has any direct interpretation in terms of selection response. The definitions of α (0) and α (∞) , lead to two distinct definitions of the average effect of an allele substitution for a model with two alleles (Fisher, 1941), and to a clarification of their significance for this breeding system.
Implementation of an emergency department triage procedure for the detection and isolation of patients with active pulmonary tuberculosis

Abstract Study objectives: To investigate the ability of an emergency department screening protocol to initiate respiratory isolation of patients with pulmonary tuberculosis at ED triage before chest radiography. Methods: We conducted a prospective cohort study with retrospective medical record review of adult patients who presented for care to an urban, university-affiliated hospital in Los Angeles County over a 4-month period. Ambulatory patients were administered a triage screening protocol that used patient-reported tuberculosis risk factors and symptoms in combination with selective chest radiography to screen patients at ED triage for active pulmonary tuberculosis. Results: A total of 10,674 patients were screened; 2,218 were isolated at triage and underwent chest radiography, and 378 were kept in isolation in the ED. The respiratory isolation of pulmonary tuberculosis (RIPT) protocol detected 17 of 27 visits made by patients with unsuspected pulmonary tuberculosis, yielding a sensitivity of 63% (95% confidence interval [CI] 42% to 81%). The estimated specificity was 78%. For each patient with tuberculosis who was detected by the RIPT protocol, 624 patients were screened at triage, 130 chest radiographs were taken, and 22 patients were placed in respiratory isolation in the ED. Patients with undetected pulmonary tuberculosis more commonly had nonpulmonary chief complaints (76% versus 20%; odds ratio [OR] 13, 95% CI 2.1 to 78.3), and only 60% (95% CI 26% to 88%) were ultimately isolated in the hospital. Among RIPT screen-positive patients, radiographic findings predictive of pulmonary tuberculosis were cavitary lesions (OR 84.3, 95% CI 22.6 to 315), upper lobe infiltrates (OR 24.2, 95% CI 9.1 to 64.4), pleural effusions (OR 8.9, 95% CI 2.5 to 31.8), diffuse/interstitial infiltrates (OR 5.7, 95% CI 1.8 to 17.9), and non–upper lobe infiltrates (OR 3.1, 95% CI 1.0 to 9.5). Conclusion: The RIPT screening protocol was only moderately sensitive for isolating patients with pulmonary tuberculosis at ED triage. Future studies should evaluate modified and abridged screening protocols, as well as the cost-effectiveness of triage screening. [Sokolove PE, Lee BS, Krawczyk JA, Banos PT, Gregson AL, Boyce DM, Lewis RJ. Implementation of an emergency department triage procedure for the detection and isolation of patients with active pulmonary tuberculosis. Ann Emerg Med. April 2000;35:327-336.]
A macroscopic profile of program compilation and linking

To profile the changes made to programs during development and maintenance, the authors have instrumented the 'make' utility that is used to compile and link programs. With minor modifications, they have used 'make' to find out how much time programmers spend waiting for compiling and linking, how many modules are compiled each time a program is linked, and the change in size of the compiled modules. Measurements show that most programs are relinked after only one or two modules are recompiled, and that over 90% of all recompilations yield object code that is less than 100 bytes larger in size. The authors are using these results to guide the design of an incremental programming environment, particularly with respect to an incremental linker. >
The study of steam explosions in nuclear systems

Abstract Recent developments in the design of nuclear systems require a more detailed examination of steam explosion energetics than has been necessary in the past. Of particular interest now are the dynamic aspects of explosions and the resulting dynamic loads on adjacent structures. A comprehensive approach towards such a goal is described and sample results are provided on 2D explosions from the recently proposed microinteractions model (the esprose .m code) and on the chemical augmentation of steam explosions with highly reactive metals.