cssi/SciSciGPT-SciSciNet huggingface dataset:
Portugal en los albores de la modernidad científica (siglo XVI)

In following a sequence of articles published in the last thirty years which discuss, on the one hand, a series of Portuguese exaggerations, and on the other, attempt to shed contemporary historiographic light on some important omissions regarding the era in which Portugal its discoveries, the present article discusses what are currently understood as the Portuguese contributions to scientific modernity. Though this recognition is generally accepted by Portuguese historians, this article locates these accomplishments within the global framework of the development of a scientific mentality and methodology, and within the general history of science.
Testosterone Treatment in Adult Men With Age-Related Low Testosterone: A Clinical Guideline From the American College of Physicians

This clinical guideline from the American College of Physicians, endorsed by the American Academy of Family Physicians, provides recommendations about testosterone treatment in adult men with age-r...
Physician Time Spent Using the Electronic Health Record During Outpatient Encounters: A Descriptive Study

Background The amount of time that providers spend using electronic health records (EHRs) to support the care delivery process is a concern for the U.S. health care system. Given the potential effect on patient care and the high costs related to this time, particularly for medical specialists whose work is largely cognitive, these findings warrant more precise documentation of the time physicians invest in these clinically focused EHR functions. Objective To describe how much time ambulatory medical subspecialists and primary care physicians across several U.S. care delivery systems spend on various EHR functions. Design Descriptive study. Setting U.S.-based, adult, nonsurgical, ambulatory practices using the Cerner Millennium EHR. Participants 155 000 U.S. physicians. Measurements Data were extracted from software log files in the Lights On Network (Cerner) during 2018 that totaled the time spent on each of the 13 clinically focused EHR functions. Averages per encounter by specialty were computed. Results This study included data from approximately 100 million patient encounters with about 155 000 physicians from 417 health systems. Physicians spent an average of 16 minutes and 14 seconds per encounter using EHRs, with chart review (33%), documentation (24%), and ordering (17%) functions accounting for most of the time. The distribution of time spent by providers using EHRs varies greatly within specialty. The proportion of time spent on various clinically focused functions was similar across specialties. Limitation Variation by health system could not be examined, and all providers used the same software. Conclusion The time spent using EHRs to support care delivery constitutes a large portion of the physicians' day, and wide variation suggests opportunities to optimize systems and processes. Primary funding source None.
Examining caregiver perceptions and distress related to patient pain.

e20555 Background: We conducted a randomized trial comparing a brief baseline pain educational intervention with the addition of either a hot line for pain related issues or weekly calls from healt...
Intraoperative fluorescence perfusion assessment should be corrected by a measured subject-specific arterial input function.

Significance The effects of varying the indocyanine green injection dose, injection rate, physiologic dispersion of dye, and intravenous tubing volume propagate into the shape and magnitude of the arterial input function (AIF) during intraoperative fluorescence perfusion assessment, thereby altering the observed kinetics of the fluorescence images in vivo. Aim Numerical simulations are used to demonstrate the effect of AIF on metrics derived from tissue concentration curves such as peak fluorescence, time-to-peak (TTP), and egress slope. Approach Forward models of tissue concentration were produced by convolving simulated AIFs with the adiabatic approximation to the tissue homogeneity model using input parameters representing six different tissue examples (normal brain, glioma, normal skin, ischemic skin, normal bone, and osteonecrosis). Results The results show that AIF perturbations result in variations in estimates of total intensity of up to 80% and TTP error of up to 200%, with the errors more dominant in brain, less in skin, and less in bone. Interestingly, error in ingress slope was as high as 60% across all tissue types. These are key observable parameters used in fluorescence imaging either implicitly by viewing the image or explicitly through intensity fitting algorithms. Correcting by deconvolving the image with a measured subject-specific AIF provides an intuitive means of visualizing the data while also removing the source of variance and allowing intra- and intersubject comparisons. Conclusions These results suggest that intraoperative fluorescence perfusion assessment should be corrected by patient-specific AIFs measured by pulse dye densitometry.
Post-mitotic myotubes repurpose the cytokinesis machinery to effect cellular guidance

Summary Myotube guidance is an essential step of muscle development that ultimately establishes the final musculoskeletal pattern, yet the mechanisms that guide post-mitotic myotubes to the correct skeletal attachment sites are poorly understood. Here, we describe a novel myogenic pathway that is regulated by the previously uncharacterized Vaccinia Related Kinase (VRK) family member Back Seat Driver (Bsd). Bsd modulates microtubule dynamics to direct myotube guidance in Drosophila embryos, and preserves cellular identity by preventing myotube-myotube fusion. Mechanistically, Bsd activates Polo kinase in nascent myotubes to regulate cellular guidance. Tumbleweed (Tum) is an essential Polo effector during cytokinesis, and we show Tum performs a critical role in attachment site selection. We also found that the mammalian Bsd orthologue Vrk3 is required for myotube morphogenesis, and that Vrk3 activates the Polo orthologue Plk1. Our studies have uncovered a conserved pathway in which Bsd activates the cytokinesis machinery in post-mitotic cells to direct myotube guidance.
Autocatalytic systems and recombination: a reaction network perspective

Autocatalytic systems are very often incorporated in the "origin of life" models, a connection that has been analyzed in the context of the classical hypercycles introduced by Manfred Eigen. We investigate the dynamics of certain networks called bimolecular autocatalytic systems. In particular, we consider the dynamics corresponding to the relative populations in these networks, and show that they can be analyzed by studying well-chosen autonomous polynomial dynamical systems. Moreover, we find that one can use results from reaction network theory to prove persistence and permanence of several types of bimolecular autocatalytic systems called autocatalytic recombination networks.
Raising the Cut-Off: The Empirical Case for Extending Adoption and Guardianship Subsidies from Age 18 to 21

Few children become financially independent at age 18. Adolescents often (and increasingly) rely financially on their parents or caretakers until an older age. Such reliance is likely to be greater among children who have been abused or neglected by their birth families, and who, by court finding, could not reunify with their parents. Parental abuse and neglect is often associated with special needs in children, and the dislocation from birth families to the foster care system imposes a short-term, and sometimes lasting, trauma. A disproportionate number of such children have a mental illness, behavioral challenges, or learning disability that may require the provision of services. Many children involved in foster care lose one or more years of school or have to repeat grades, leaving them living at home enrolled fulltime in secondary school past the age of 18. Adoption and guardianship subsidies may offset part of the cost of accepting permanent responsibility for the care of a child who has been in foster care. But not all adoption and guardianship subsidies can be extended to cover costs of support past the age of 18. We explore the effects of extending adoption subsidies to age 21. Does extending subsidies increase the number of adoptions and legal guardianships from state foster care systems? Administrative data from state child welfare systems strongly suggests that the answer is affirmative.
Leading-Following: Nurse-Led Care Center Exemplars.

There are many ways to lead across all healthcare settings. It is important for nurses to find a way of leading that is grounded in unique nursing knowledge that is consistent with their values and...
Salmonella dublin Infections in Cattle in California

Salmonellosis is a commonly encountered disease of cattle. Of the many serotypes of Salmonella known to exist, Salmonella typhimurium and S. dublin are the two most frequently isolated from cattle. Salmonella dublin is isolated commonly from cattle in states west of the Rocky Mountains. Reports of isolations of S. dublin from states east of the Rockies are increasing.2,4 Salmonella dublin is also isolated commonly in Europe and South Africa. Unlike S. typhimurium, which shows no special affinity for a particular host, S. dublin is host-adapted for cattle. While other animal species can be infected with S. dublin, cattle account for approximately 96% of the isolations from animals. This host-adaptation for cattle has special implications regarding epidemiology and control measures. The purpose of this presentation is to give an overview of the current spectrum of S. dublin infections in dairy cattle in California.
Is PM2.5 associated with emergency department visits for mechanical ventilation in acute exacerbation of chronic obstructive pulmonary disease

Abstract Background Patients with chronic obstructive pulmonary disease (COPD) can have recurrent exacerbations and acute respiratory failure (ARF) triggered by particulate matter with a diameter of ≤2.5 μm (PM2.5). To prevent ventilator shortages, this study investigated the short-term association between PM2.5 concentration and emergency department visits (EDVs) among patients with acute exacerbation of COPD (AECOPD) requiring mechanical ventilation (MV). Methods We conducted a time-series study to predict the PM2.5 concentration and number of ventilators needed. Daily counts of EDVs among AECOPD patients requiring ventilation from 2015 to 2019 were obtained from a hospital. Generalized linear models extending Poisson regression were used to explore the association of AECOPD with PM2.5 after controlling for the time trend, seasonal variations, and meteorological variables. Results Eight hundred seventy-five AECOPD patients receiving MV were recorded, of whom 734 received noninvasive ventilation and 141 received invasive ventilatory support. EDVs for AECOPD patients with ARF significantly increased by 3.5% (95% confidence interval [CI]: 2.51%–4.42%) per 10 μg m−3 increase in PM2.5 concentration. Among seasons, PM2.5 concentration had the strongest effect on AECOPD patients with ARF in spring ( Conclusion This is the first study to predict the number of ventilators required by calculating quantitative estimates of the short-term effects of PM2.5 on EDVs for AECOPD patients with ARF. Adverse effects of PM2.5 on AECOPD patients requiring MV are evident, especially in the spring. Establishing protective standards and reducing the PM2.5 concentration to below various thresholds are urgently needed.
Modular Hybrid Step-Down PFC Converter for Direct AC/DC Conversion with Differential Power Processing in Data Centers

In this work, differential power processing for AC/DC applications has been explored with a switched-capacitor (SC) based hybrid step-down converter. The converter can provide required AC/DC step-down conversions with a high power factor and eliminate intermediate high-voltage DC-link bus and capacitors. Instead, compact low-voltage capacitors are utilized as flying capacitors in the 4-level SC part of the converter that also provides line-frequency distributed energy buffer capability. In order to support higher input AC voltages, the inputs of two converter unit modules are connected in series while their outputs supply two separate loads in an AC/DC differential power processing architecture. This architecture can be used for data centers and telecommunication systems. In this paper, the operation for a single module and multiple modules are verified with a 115VAC-to-48VDC conversion and 200VAC input to two 48VDC outputs, respectively. The experimental results confirm the converter topology, individual operation, and modular operation along with the control method. A single converter achieves 95.8% efficiency at 115VAC-to-48VDC/10A load with a 0.994 power factor.
Linton Family LLC and the Step Transaction Doctrine

This article discusses Linton, a district court decision about a family limited liability company, indirect gifts, and the step transaction doctrine.
Access to What? Mission Differentiation and Academic Stratification in U.S. Public Higher Education.

Academic policy initiatives have long been apowerful lever for mission differentiationwithin U.S. public higher education. Althoughthe higher education literature has examinedbasic issues in the design of public systems,the tension between access and differentiationhas not been explored. Drawing uponcomparative case studies of public highereducation in Massachusetts and New York, thisarticle examines recent policy initiatives toterminate academic programs, eliminate remedialeducation, and promote honors colleges withineach state system. The analysis depicts howthese policies contribute to increasedstratification of programs and students withina state system as well as within particularcampuses in a system. The authors argue thatpolicy analysis in higher education shoulddevelop a more refined conceptualization ofaccess that examines the cumulative impact ofcontemporary policies on the stratification ofstudent opportunity.
Debt and Equity

Which is better for a small firm: debt financing or equity financing? A simple intertemporal model suggests that the two have very different potential incentive problems. With equity financing, the manager (an employee) may expend too little effort, while with debt financing, the manager (the owner) may keep the entire cash flow and default on the debt. Depending on the relative severity of these two incentive problems, either debt or equity may dominate the other. These problems are exacerbated by the possibility of an MBO and are reduced by sinking funds, stock or option compensation and non-vested pensions.
Flower arranging in Arabidopsis.

The flowering of plants in response to changes in day length and temperature is controlled by three intricate signaling pathways. In this Perspective, [Devlin and Kay][1] examine new research ([ Samach et al .][2]) that shows how signals from the three pathways converge on the promoters of several key genes to bring about flowering in the model plant Arabidopsis . [1]: http://www.sciencemag.org/cgi/content/full/288/5471/1600 [2]: http://www.sciencemag.org/cgi/content/short/288/5471/1613
Castleman disease presenting as a pelvic mass

Background: To our knowledge, giant lymph node hyperplasia (Castleman disease) may present as a pelvic mass on magnetic resonance imaging (MRI). Case: A postmenopausal woman with rapidly enlarging leiomyoma uteri was found to have a suspicious left adnexal mass mimicking an ovarian neoplasm on preoperative MRI. At laparotomy, the suspected uterus and normal ovaries were extirpated. In addition, a firm, 4 × 8-cm solid mass within the sigmoid colon mesentery was found and resected. The final histologic diagnosis was Castleman disease. Conclusion: Entities such as Castleman disease should be considered when assessing a pelvic mass. Characterization of the origin of pelvic masses can often be difficult, despite sophisticated diagnostic imaging studies such as MRI.
Observations of O VI

A useful spectroscopic tracer for a hot phase of interstellar gas is the O VI ion, which reaches its maximum concentration in collisional ionization between 105 and 106 K. Presently, over 70 stars have been observed for O VI absorption by the Copernicus satellite. Nearly all of the stars show broad, weak lines, but no evidence favoring a circumstellar origin for the gas can be found. An overall average for ne of the hot gas in the galactic plane is of order 10−3 cm−3. The relative volume in space occupied by the hot gas regions (and hence their internal density) is uncertain, but a filling factor in the range 0.02 to 0.2 seems most plausible. Fluctuations in radial velocities and column densities suggest there are roughly 6 regions per kpc, each with N(0 VI) ≈ 1013 cm−2. The observed rms dispersion of radial velocities for these regions is 26 km s−1.
A New Numerical Algorithm for Thermoacoustic and Photoacoustic Tomography with Variable Sound Speed

We present a new algorithm for reconstructing an unknown source in Thermoacoustic and Photoacoustic Tomography based on the recent advances in understanding the theoretical nature of the problem. We work with variable sound speeds that might be also discontinuous across some surface. The latter problem arises in brain imaging. The new algorithm is based on an explicit formula in the form of a Neumann series. We present numerical examples with nontrapping, trapping and piecewise smooth speeds, as well as examples with data on a part of the boundary. These numerical examples demonstrate the robust performance of the new algorithm.
Measuring the Running Coupling Constant of the Strong, the Electromagnetic and Weak Forces

Lord Kelvin once wrote that every basic principle worth mentioning had already been discovered and that all that was needed were more precise measurements. Shortly after that, in 1897, J.J. Thomason discovered the first lepton (the electron) and opened the first chapter of elementary particle physics. The discovery of the J particle in 1974, interpreted as the bound state of a quark-antiquark pair with a new flavor, charm (much in the same fashion as the hydrogen atom is the bound state of the proton and electron), put the finishing touch to the hypothesis that quarks are the fundamental building blocks of all hadrons. Now we know our universe is likely to be made of 6 leptons and 6 quarks. They interact with each other by means of 4 interactions: nuclear (or strong), electro-magnetic, weak forces and gravity; each is distinctively different in nature and in magnitude at the energy scale commonly available in nature. Each of these forces is characterized by a coupling constant which roughly determines the size of the interaction. Most of our daily phenomena, from the maximum height of a mountain and living beings to temperatures of the sun and the earth can be explained in terms of these constants. Since Einstein’s unsuccessful efforts to unify gravity with electromagnetic forces at low energies, physicists have attempted, over many years, to unify these interactions at much higher energies than presently available in the laboratories. According to these speculations, the coupling constants of all forces will change with energy and at sufficiently high energy they will become comparable in size (Fig. 1). This property of changing with energy resulted in the name of “running coupling constants”. In these lectures we will take a few examples, primary from e+e− annihilation to illustrate the effort in measuring these constants at different energies.
Sodium Channel β4, a New Disulfide-Linked Auxiliary Subunit with Similarity to β2

The principal alpha subunit of voltage-gated sodium channels is associated with auxiliary beta subunits that modify channel function and mediate protein-protein interactions. We have identified a new beta subunit termed beta4. Like the beta1-beta3 subunits, beta4 contains a cleaved signal sequence, an extracellular Ig-like fold, a transmembrane segment, and a short intracellular C-terminal tail. Using TaqMan reverse transcription-PCR analysis, in situ hybridization, and immunocytochemistry, we show that beta4 is widely distributed in neurons in the brain, spinal cord, and some sensory neurons.beta4 is most similar to the beta2 subunit (35% identity), and, like the beta2 subunit, the Ig-like fold of beta4 contains an unpaired cysteine that may interact with the alpha subunit. Under nonreducing conditions, beta4 has a molecular mass exceeding 250 kDa because of its covalent linkage to Nav1.2a, whereas on reduction, it migrates with a molecular mass of 38 kDa, similar to the mature glycosylated forms of the other beta subunits. Coexpression of beta4 with brain Nav1.2a and skeletal muscle Nav1.4 alpha subunits in tsA-201 cells resulted in a negative shift in the voltage dependence of channel activation, which overrode the opposite effects of beta1 and beta3 subunits when they were present. This novel, disulfide-linked beta subunit is likely to affect both protein-protein interactions and physiological function of multiple sodium channel alpha subunits.
The temporal specific role of WNT/β-catenin signaling during myogenesis

Disruption of WNT/β-catenin signaling causes muscle developmental defects. However, it has been unclear how WNT/β-catenin signaling regulates each step of myogenesis. The in vitro culture of primary myoblasts and C2C12 cells (a myoblast cell line) has the ability to differentiate into myofibers in culture with differentiation inducers. These in vitro systems are useful to investigate each step of muscle development, ranging from cell proliferation to homeostasis, under the control of experimental conditions. Our recent study shows that WNT/β-catenin signaling can regulate myogenesis in a temporal specific manner by controlling the gene expression of cyclin A2 (Ccna2) and cell division cycle 25C (Cdc25c) during myoblast proliferation and fermitin family homolog 2 (Fermt2) during myoblast fusion and differentiation, respectively. In the well-differentiated myofibers, WNT/β-catenin signaling plays a role in the maintenance of their structure through a cadherin/β-catenin/actin complex formation, which is important for connecting a myofiber's cytoskeleton to the surrounding extracellular matrix. Thus, our recent study coupled with previous findings indicates that WNT/β-catenin signaling regulates myogenesis in a variety of ways, and any failure of these steps of myogenesis causes muscle developmental defects.
Treatment outcomes and late complications of 849 patients with nasopharyngeal carcinoma treated with radiotherapy alone.

Purpose: The objective of this study was to describe the treatment outcomes and treatment-related complications of nasopharyngeal carcinoma (NPC) patients treated with radiotherapy alone. Methods and Materials: Retrospective analysis was performed on 849 consecutive NPC patients treated between 1983 and 1998 in our institution. Potentially significant patient-related and treatment-related variables were analyzed. Radiation-related complications were recorded. Results: The 5-year overall and disease-free survival rates of these patients were 59% and 52%, respectively. Advanced parapharyngeal space (PPS) invasion showed stronger prognostic value than PPS invasion. Multiple neck lymph node (LN) involvement was demonstrated to be one of the most powerful independent prognostic factors among all LN-related parameters. External beam radiation dose more than 72 Gy was associated with significantly higher incidence of hearing impairment, trismus, and temporal lobe necrosis. Conclusions: We recommend that the extent of PPS should be clarified and stratified. Multiple neck LN involvement could be integrated into the N-classification in further revisions of the American Joint Committee on Cancer stage. Boost irradiation is not suggested for node-negative necks. For node-positive necks, boost irradiation is indicated and a longer interval between initial and boost irradiation would reduce the incidence of neck fibrosis without compromising the neck control rate.
Numerical approximation of the Vlasov-Poisson-Fokker-Planck system in two dimensions

A numerical method is developed for approximating the solution to the Vlasov-Poisson-Fokker-Planck system in two spatial dimensions. The method generalizes the approximation for the system in one dimension given in [S. Wollman, E. Ozizmir, Numerical approximation of the Vlasov-Poisson-Fokker-Planck system in one dimension, J. Comput. Phys. 202 (2005) 602-644]. The numerical procedure is based on a change of variables that puts the convection-diffusion equation into a form so that finite difference methods for parabolic type partial differential equations can be applied. The computational cycle combines a type of deterministic particle method with a periodic interpolation of the solution along particle trajectories onto a fixed grid. computational work is done to demonstrate the accuracy and effectiveness of the approximation method. Parts of the numerical procedure are adapted to run on a parallel computer.
Efficient Direct Measurement Mode Survey Test Procedure

An efficient, direct measurement mode survey test procedure is presented. The procedure derives from the recognition that single-shaker frequency response functions of a linear, elastic structure can be scaled and summed to yield frequency response functions corresponding to multiple-shaker excitation. Thus, the operations to establish the multiple force levels needed to isolate modes for measurement can be performed numerically on a small laboratory computer/data acquisition system. In addition, this also introduces the possibility of numerically identifying mode parameters from single-shaker frequency response functions by using traditional sine-dwell testing techniques.
The Public-Service Employment Program

In this paper, a four-year field network study of the public-service employment program under the Comprehensive Employment and Training Act is described. The emphasis of the study was on displacement—the extent to which states and local governments used federally subsidized workers in place of locally funded workers. A description of the field network methodology is also included.
Experimental and theoretical studies of the dislocation structure of NiO-Pt interfaces

Abstract The dislocation structure of (001) NiO-Pt interfaces was studied using electron microscopy and electron diffraction techniques. Specimens were produced by hot pressing polycrystalline Pt films on to thin NiO single crystals, and bulk Pt single crystlas on to bulk NiO single crystals. The polycrystalline Pt specimens were used to determine the favored orientation relationships between the (001) NiO and Pt, while the bulk NiO-Pt specimens were used to study the detailed structur of interface. Three categories of orientation relationships were identified: exact epitaxy with (001) pt ∥ (001) NiO , [110] Pt ∥ [110] NiO ; small rotations away from exact epitaxy about the common [001] direction, and high index planes of Pt parallel to (001) of NiO. Theoretical calculations of the expected dislocation structures of interfaces with the first two orientation relationships, as well as others which are small perturbations away from these two, were made using a Bollmann-type analysis. The experimental observations and theoretical predictions were shown to be in generally good agreement, with some differences with respect to the detailed structure. The energies of the interfaces having the first two orientation relationships were shown to be similar which is believed to be the reason why they both occur.
Associations of Elevated Liver Enzymes among Hospitalized Adolescents with Anorexia Nervosa

Objectives To analyze the prevalence, predictors, and evolution of increased liver enzymes in a large sample of adolescents hospitalized with anorexia nervosa (AN). Study design Electronic medical records of all subjects 10-22 years of age with AN, first admitted to a tertiary children's hospital from January 2007 to December 2012, were reviewed retrospectively. Demographic factors, anthropometric factors, initial prescribed calories, and alanine aminotransferase levels were recorded. Multivariate analysis was performed to assess the effect of sex, degree of malnutrition, and initial calories prescribed on having alanine aminotransferase ≥40 IU/L. Results A total of 356 subjects met eligibility criteria (age 16.1 ± 2.4; 89.0% female; admission body mass index [BMI] 15.9 ± 1.9; admission percentage median BMI 78.2 ± 8.5), with elevated liver enzymes present in 37.0% on admission and in 41.1% at any point during the hospitalization. Lower percentage median BMI (aOR 0.96; 95% CI 0.93-0.98) and male sex (aOR 0.45; 95% CI 0.22-0.94) were significantly associated with odds of elevated liver enzymes on admission. Higher initial prescribed calories were associated with odds of elevated liver enzymes after admission (aOR 1.81; 95% CI 1.04-3.18). Conclusions In this study of AN and elevated liver enzymes, the degree of malnutrition and male sex predicted elevated liver enzymes on admission but initial prescribed calories also may be associated with elevated liver enzymes after admission in a small proportion of patients. Future research should better characterize the evolution of elevated liver enzymes in patients hospitalized with AN undergoing refeeding.
Module design with substitute parts and multiple vendors

Abstract In this paper, we present a model to design a single standard module when many parts can satisfy a particular technical requirement and parts may be purchased from a variety of vendors. The model attempts to minimize the total fixed costs for using vendors and parts, and the total variable costs for parts. Technical requirements for the set of products are modeled by requiring a miniml number of parts from each substitution group in each product. Also, life cycle demand must be met. We present an algorithm and a heuristic to solve the model. We include initial computational results that demonstrate that the heuristic performs well on the problems tested.
Water-related matrix isolation phenomena during NO2 photolysis in argon matrix.

Photolysis (350–450 nm) of NO2 molecules trapped in argon matrices at 10 K has been studied using Fourier transform infrared (FTIR) spectroscopy to examine the mobility of the photolysis products, O(3P) and NO, and their subsequent reactions. The formation of N2O5 and N2O3 from reactions of these mobile species with immobilized NO2 and N2O4 is confirmed. Water molecules from the background gases in the vacuum have been found to be isolated in the argon matrix during deposition of diluted NO2 in Ar. The entrapped water molecules along with some of their NO2 adducts have been characterized. Exposure of the matrix to photons to photolyze NO2 resulted in not only internal matrix reactions, but also an enhanced deposition of ice over the surface of the argon matrix. This is caused by photodesorption of water molecules from the walls of the matrix isolation chamber and their subsequent condensation on the matrix surface. This ice overlayer has been found to give a very significant dangling OH band and a substantial librational band in the FT-IR spectra, indicating substantial surface area and internal porosity, respectively. The potential of using photodesorbed water to establish high surface area ice interfaces with dangling OH groups for heterogeneous photoreaction studies is discussed.
Vulnerable populations in research: the case of the seriously ill.

This paper advances a new criterion of a vulnerable population in research. According to this criterion, there are consent-based and fairness-based reasons for calling a group vulnerable. The criterion is then applied to the case of people with serious illnesses. It is argued that people with serious illnesses meet this criterion for reasons related to consent. Seriously ill people have a susceptibility to “enticing offers” that hold out the prospect of removing or alleviating illness, and this susceptibility reduces their ability to safeguard their own interests. This explains the inclusion of people with serious illnesses in the Belmont Report’s list of populations needing special protections, and supports the claim that vulnerability is the rule, rather than the exception, in biomedical research.
On the dynamic response of impure molecular crystals

The total wave function of an impure molecular crystal is resolved, using the partitioning technique, into two components, one restricted to the host lattice and one which describes the interaction between the isolated impurities and the host. The two components differ by a phase which can be a rapidly varying function of the energy. Typical interference effects can thus be demonstrated when the linear response to an external perturbation is observed. A model of a one-dimensional linear chain is considered and explicit results are obtained using an integral Hellmann-Feynman theorem for two potentials.
Pairing of holes in the spin liquid: Possible application to the high-temperature superconductors.

A mechanism is proposed for the pairing of holes in the resonating-valence-bond (RVB) state for two-dimensional alternate lattices such as found in copper oxide high-${T}_{c}$ materials. The main ingredients of the attractive force are the kinetic motion of holes which in fact stabilizes the RVB state and the topological and statistical nature of the RVB state. The size of a pair of holes is the order of the antiferromagnetic correlation length. A schematic phase diagram in terms of the concentration of holes and temperature is drawn which includes a paramagnetic phase, an antiferromagnetic phase, two types of spin-liquid phases, and a superconducting phase.
Another Failure to Generalize the Mozart Effect

Several studies have not replicated Rauscher, Shaw, and Ky's 1993 finding that 10 minutes of exposure to Mozart piano music temporarily enhanced performance on three spatial reasoning tasks. Later Rauscher and Shaw argued that enhanced performance is unlikely unless three conditions are met. The present study was designed to meet those three conditions. 36 adults were exposed to one of six listening orders and one of six test orders. Listening and test orders had no systematic effect on spatial reasoning performance. A one-factor, repeated-measures analysis of variance yielded no significant difference on spatial reasoning performance after listening to classical music, jazz, or silence. A reanalysis, using only those items most likely to tap spatial reasoning, fell short of significance, and mean scores were in the direction opposite to that hypothesized. These results were inconsistent with studies that have supported a Mozart effect.
Twin DNA Pumps of a Hexameric Helicase Provide Power to Simultaneously Melt Two Duplexes

DnaB is the primary replicative helicase in Escherichia coli. We show here that DnaB can unwind two duplex arms simultaneously for an extended distance provided that two protein rings are positioned on opposite sides of the duplex arms. A putative eukaryotic replication fork helicase, Mcm4,6,7, performs a similar activity. Double-ringed melting of duplexes may function at a replication fork in vivo. This mechanism may apply to RuvB, since the proteins share mechanistic similarities. Thus, two RuvB hexamers may function in coordination at a Holliday junction to overcome regions of DNA heterology and DNA lesions. Furthermore, DnaB can actively translocate along DNA while encircling three DNA strands. Therefore, if DnaB encounters a D loop during fork progression, it will encircle the invading strand and may convert the recombinative invading strand to a daughter lagging strand. Finally, we present evidence that the DNA binding site of DnaB is buried inside its central channel.
Subdifferentiability and lipschitz continuity in experimental design problems

The calculus of concave functions is a widely accepted tool for optimum experimental design problems. However, as a function of the support points and the weights the design problem fails to be concave. In this paper we make use of generalized gradients in the sense of Rockafellar (1980) and Clarke (1983). A chain rule is presented for the subdifferential of the composition of an information function with the moment matrix mapping. Lipschitz continuity of the global design function is proved and conditions for strict differentiability are given.
The quintessential exotic X(3872)

Abstract The experimental evidence for the exotic meson, X(3872), is summarized and the various proposed theoretical models for it are reviewed. It is pointed out that several important experimental measurements have marginal statistical significance and disagreements between different sources. Until these problems are resolved, the understanding of the structure of X(3872) is likely to remain controversial.
An analytical model for reverse automotive production planning and pricing

Abstract Automotive shredders need a reverse production planning strategy that includes determining at what price to purchase vehicle hulks from different sources. In this paper, we formulate the automotive reverse production planning and pricing problem in a nonlinear programming model, develop an approximate supply function for hulks when adjacent shredders price independently, and compare two hulk pricing strategies in three trends for ferrous metal and hulk prices: constant, increasing and decreasing. The case study results indicate that adjusting purchase price based on hulk composition in coordination with planning for purchasing, storing and processing can increase net revenue by 7–15%.
On families of quadratic surfaces having fixed intersections with two hyperplanes

We investigate families of quadrics all of which have the same intersection with two given hyperplanes. The cases when the two hyperplanes are parallel and when they are nonparallel are discussed. We show that these families can be described with only one parameter and describe how the quadrics are transformed as the parameter changes. This research was motivated by an application in mixed integer conic optimization. In that application, we aimed to characterize the convex hull of the union of the intersections of an ellipsoid with two half-spaces arising from the imposition of a linear disjunction.
ABSCISIC ACID INDUCES LAND FORM CHARACTERISTICS IN MARSILEA QUADRIFOLIA L.

Variation de la morphologie foliaire, accroissement de la surface des folioles, differenciation des stomates et des trichomes, elongation des petioles et des racines, developpement des racines laterales, raccourcissement des rhizomes et reduction du nombre de feuilles et de racines formees sur chaque plant
Attenuation coefficients of body tissues using principal-components analysis.

Principal‐components analysis is used to obtain a set of parameters for dual‐energy radiography that completely describes the attenuation coefficient of any tissue over a given energy range. These parameters are the weighted averages of the densities of the elements present in a substance. Principal‐components (PC) parameters are calculated for several soft tissues from measured attenuation coefficients published by Phelps e t a l. The calculated PC parameters are compared to the more conventional dual‐energy representations of the attenuation coefficient: (1) the electron density/effective atomic number (or Compton/photoelectric) representation and (2) the equivalent water/equivalent aluminum thickness representation. The principal‐components parameters represent the attenuation coefficients more accurately, and are more stable than the currently used parameters. In addition, these new parameters are sensitive to differences in the chemical composition and density, whereas the previous representations are primarily sensitive to changes in the density. It is concluded that the principal‐components method provides a more sensitive and accurate indicator of changes in tissue composition than previous characterizations of the linear attenuation coefficient. The principal‐components method provides a means for improving the accuracy of the characterization of tissues in dual‐energy computed tomographic imaging and in dual‐energy digital radiography.
LOCAL STATE DYNAMICS AND GENTRIFICATION IN INDIANAPOLIS, INDIANA

This article seeks to demonstrate that the creation of the rent-gap is not the only important variable which structures patterns of neighborhood gentrification in North American cities. A case study of Indianapolis, Indiana, between 1980 and 1986 illustrates the influence of the local state as an alternative variable. Its influence, directed toward the aim of transforming the downtown area for more affluent users, was twofold. First, government regulated upgrading, via the construction of rules and ordinances, to ensure the process's inevitable success. Then, to direct its spatial unfolding, subsidies were targeted to stimulate the production of gentrified dwellings. Thus, government provided investors the power to fulfill their redevelopment objectives and subsidized their operations. The end product of "politicizing" the marketplace was to shape its dynamics, and, ultimately, its market outcomes.
The future of toxicity testing: a focus on in vitro methods using a quantitative high-throughput screening platform

The US Tox21 collaborative program represents a paradigm shift in toxicity testing of chemical compounds from traditional in vivo tests to less expensive and higher throughput in vitro methods to prioritize compounds for further study, identify mechanisms of action and ultimately develop predictive models for adverse health effects in humans. The NIH Chemical Genomics Center (NCGC) is an integral component of the Tox21 collaboration owing to its quantitative high-throughput screening (qHTS) paradigm, in which titration-based screening is used to profile hundreds of thousands of compounds per week. Here, we describe the Tox21 collaboration, qHTS-based compound testing and the various Tox21 screening assays that have been validated and tested at the NCGC to date.
Skin self-examination practices in a convenience sample of US university students

Background. Melanoma skin cancer affects many young adults, yet few practice skin self-examination (SSE). We collected detailed information about young adult SSE practices, which can be used to guide the development of SSE interventions that target this age group. Methods. We surveyed 190 US university students to assess their SSE practices, including thoroughness of self-exams and reasons for not performing SSE. Results. Just 33.2% of respondents had ever performed SSE, and only 5.8% had checked their entire body. The three most commonly cited reasons for failing to practice SSE were not knowing what to look for (55.9%), never thinking of it (54.3%), and not knowing it should be done (33.1%). Conclusions. Interventions to promote early melanoma detection must raise awareness about the importance of beginning SSE practice in young adulthood and conducting thorough self-exams. They should target all young adults, including those who already practice SSE.
Hematogenous metastases to the stomach. A review of 67 cases

Metastatic tumors to the mucosa of the stomach are unusual occurrences that can cause clinical and pathologic problems in diagnosis. The authors report 67 cases from the files of the Veterans Administration Center at Houston. Ten cases were found on endoscopic biopsy and 57 at necropsy. Each patient endoscopically evaluated presented with upper gastrointestinal tract symptoms, including bleeding, abdominal pain, anorexia, and vomiting. At endoscopic examination, characteristic "volcano-like" ulcers were noted. Clinical gastrointestinal symptoms were present in 30 of the necropsy cases, and in four cases the gastric metastases led to the patients' deaths. Tumors primary in the lung accounted for most of the metastases (55%), followed by other gastrointestinal malignancies. A correct diagnosis is important to direct therapy and is facilitated by the characteristic clinical, endoscopic, and histologic findings.
Comparative evaluation of biofilm disinfectant efficacy tests

Regulatory agencies are receiving registration applications for unprecedented, antibiofilm label claims for disinfectants. Reliable, practical, and relevant laboratory biofilm test methods are required to support such claims. This investigation describes the influence of fluid dynamics on the relevancy of a laboratory test. Several disinfectant formulations were tested using three different biofilm testing systems run side-by-side: the CDC biofilm reactor system that created turbulent flow (Reynolds number between 800 and 1850), the drip flow biofilm reactor system that created slow laminar flow (Reynolds number between 12 and 20), and the static biofilm system that involved no fluid flow. Each comparative experiment also included a dried surface carrier test and a dried biofilm test. All five disinfectant tests used glass coupons and followed the same steps for treatment, neutralization, viable cell counting, and calculating the log reduction (LR). Three different disinfectants, chlorine, a quaternary ammonium compound, and a phenolic, were each applied at two concentrations. Experiments were conducted separately with Pseudomonas aeruginosa and Staphylococcus aureus and every experiment was independently repeated. The results showed that biofilm grown in the CDC reactor produced the smallest LR, the static biofilm produced the largest LR, and biofilm grown in the drip flow reactor produced an intermediate LR. The differences were large enough to be of practical importance. The dried surface test often produced a significantly higher LR than the tests against hydrated or dried biofilm. The dried biofilm test produced LR values similar to those for the corresponding hydrated biofilm test. These results show that the efficacy of a disinfectant must be measured by using a laboratory method where biofilm is grown under fluid flow conditions similar to the environment where the disinfectant will be applied.
A note on Walrasian equilibria in non-Walrasian models

Abstract We demonstrate that equilibria termed ‘Walrasian’ in non-Walrasian models are generally not, but rather Hicksian Temporary Competitive Equilibria in expected virtual prices. They are only Walrasian when the expected virtual prices would clear all markets.
Kinetics of hydrogen in preparing amorphous B5C:H thin films

The kinetics of hydrogen in preparing amorphous boron carbide (a-B5C:H) thin films was studied. The hydrogen concentration of a-B5C:H thin films formed by plasma-enhanced chemical vapor deposition (PECVD) from a single-source precursor (o-B10C2H12) is ∼35–50 at.% as determined by nuclear reaction analysis. The hydrogen concentration of the a-B5C:H thin films is an exponential function of the precursor flux during the deposition. After annealing, the hydrogen concentration in the a-B5C:H thin films decreases with the increasing annealing temperature. The kinetics of hydrogen removal during annealing is controlled predominantly by its dissociation from PECVD radicals in the a-B5C:H thin films. The activation energy of about 0.14 eV is related to hydrogen dissociation from B–H bonds, but higher activation energy (∼0.44 eV) is required to strip the hydrogen atoms from C–H bonds in the thin films.