cssi/SciSciGPT-SciSciNet huggingface dataset:
Enhanced magnetic anisotropy in cobalt-carbide nanoparticles

An outstanding problem in nano-magnetism is to stabilize the magnetic order in nanoparticles at room temperatures. For ordinary ferromagnetic materials, reduction in size leads to a decrease in the magnetic anisotropy resulting in superparamagnetic relaxations at nanoscopic sizes. In this work, we demonstrate that using wet chemical synthesis, it is possible to stabilize cobalt carbide nanoparticles which have blocking temperatures exceeding 570 K even for particles with magnetic domains of 8 nm. First principles theoretical investigations show that the observed behavior is rooted in the giant magnetocrystalline anisotropies due to controlled mixing between C p- and Co d-states.
The olfactory bulb and medial hemisphere wall of the rat‐fish, Chimaera

The Chimaerae are phylogenetically old cartilagenous fish which are included in the class Chondrichthyes with the sharks and rays. The telencephalon of these fish is connected to the diencephalon by a unique fibrous stalk. The telencephalic hemispheres are united only ventrally at midhemisphere levels in the region of the hippocampal and anterior commissures. The lateral ventricles join the midline ventricle through the interventricular foramen at this level. Each olfactory bulb is divided into a dorsal and ventral part and each has a dorsal and a ventral accessory olfactory bulb. A dorsal and a ventral olfactory nerve unite the respective parts of the bulb with a nasal sac. The cup-shaped mitral cell laminae share a common granular cell layer where they are in apposition. The granular lamina is replaced caudally by the anterior olfactory nucleus. The medially situated primordial hippocampal formation consists of the anterior continuation, the primordial subiculum, the cornu ammonis and the dentate gyrus. Septal nucleu recognizable in this form include: a medial and a lateral septal nucleus, a septohippocampal nucleus, a nucleus triangularis, an accumbens nucleus, and a nucleus of the diagonal band. The medial zone of the olfactory tubercle occupies the ventromedial hemisphere wall. Major fiber connections of the medial limbic lobe include: the medial olfactory tract, the fornix, the medial forebrain bundle and the medial corticohabenular tract.
Structure and Density of FeS at High Pressure and High Temperature and the Internal Structure of Mars

In situ x-ray diffraction measurements revealed that FeS, a possible core material for the terrestrial planets, transforms to a hexagonal NiAs superstructure with axial ratio (c/a) close to the ideal close-packing value of 1.63 at high pressure and high temperature. The high-pressure-temperature phase has shorter Fe-Fe distances than the low-pressure phase. Significant shortening of the Fe-Fe distance would lead to metallization of FeS, resulting in fundamental changes in physical properties of FeS at high pressure and temperature. Calculations using the density of the high-pressure-temperature FeS phase indicate that the martian core-mantle boundary occurs within the silicate perovskite stability field.
Coset codes in a multi-hop network

Error-correction coding techniques have been used to exploit imperfections in the physical layer of the communications protocol stack to obtain both reliability and security without the need for secret keys. In a multi-hop network, however, colluding eavesdropping nodes can share information to effectively reduce errors in the eavesdropping channels and, hence, overcome the secrecy offered through coding. This paper presents a simple method for preventing an eavesdropper from gaining an advantage by listening to several transmissions of the same codeword. The technique can be used in multi-hop networks, and communications systems that employ automatic repeat request (ARQ) for data reliability.
Genetics, age, and infertility

Abstract Objective : To review the genetics of aging specifically as it pertains to human fertility, as well as the recent advancements in the diagnosis of genetic diseases prior to embryo implantation. Methods : A review of our own experience as well as the scientific literature with regards to the decline in female fertility with age, the success of IVF in women of older reproductive age, and the role of preimplantation genetic diagnosis (PGD) in the evaluation of the patient at risk for fetal genetic anomalies. Results : The decline in female fertility occurs primarily as a result of a decline in oocyte quality as well as quantity. The frequency of chromosomal anomalies in recognized abortuses increases in parallel with the age-specific rise in the incidence of spontaneous abortions. PGD is an accurate diagnostic tool for exclusion of genetically deficient embryos prior to initiation of pregnancy. Conclusion : Reproductive failure in women of older age appears to be directly related to ovarian age. Recent techniques such as cytoplasmic or germinal vesicle transfer are designed to replace the senescent cellular machinery believed to be responsible for genetic errors that occur during early cell division. PGD can accurately identify embryos with genetic deficiencies prior to implantation.
Analysis of nucleotide pools in human lymphoma cells by capillary electrophoresis.

Abstract Capillary electrophoresis is applied to determine nucleotide pool levels in human Burkitt lymphoma cells. The analysis was performed on a 65 cm × 50 μm I.D. Ucon-coated column with on-column UV detector. The method requires only nanoliters of sample and a simple sample preparation procedure. Over 12 nucleotides were separated and quantitated with high resolution and reproducibility. The whole capillary electrophoretic separation time was only 35 min. These results demonstrate that capillary electrophoresis provides a useful and easy way to analyze nucleotide pools in cells.
Effects of an experimental increase in prey abundance upon the reproductive rates of two orb-weaving spider species (Araneae: Araneidae)

A field experiment was performed to determine if food is a limited resource for adult females of two species of orb-weaving spiders, Mecynogea lemniscata and Metepeira labyrinthea. Spiders built webs after being added to open experimental units located in a mixed deciduous-pine forest in Maryland, USA. Each unit was a frame supporting dead branches of the type used by both species for anchoring webs. Spiders on half the units were exposed to natural prey densities only, while each spider on the other units was given laboratory-reared flies in order to increase prey availability above natural levels. Supplemental feeding continued for 2.5 months. At the end of the experiment all egg sacs were removed from the units.Providing additional prey did not increase the survival rate on the units (net effect of mortality, emigration and immigration). However, both species responded to additional prey by significantly increasing the number of eggs produced per female, indicating that food was a limited resource for these species. Median egg production per female increased from 34 to 62 for Mecynogea lemniscata and from 65 to 145 for Metepeira labyrinthea. Egg weight was not affected.Feeding rates and nearest neighbor distances were determined for spiders in non-experimental populations, which permitted evaluation of the experiment's naturalness. The effects of food supply upon the reproductive rates of the two species are discussed in relation to their numerical response and population dynamics.
Numerical solution of hereditary control problems using necessary conditions

Abstract A centered difference method for the boundary value problems arising as necessary conditions for hereditary control problems is given. Convergence and convergence rates are established and numerical examples are presented and compared with other results in the literature.
Numerical wavefront propagation through inhomogeneous media

An efficient simple numerical procedure is used to produce the motion of shockfront with small amplitude through inhomogeneous media. The mathematical model uses an intrinsic coordinate system and is based on Whitham's (1974) theory of geometrical shock dynamics. By using this model, the motion of the wavefront can be determined without explicitly calculating the flowfield quantities behind the wavefront. The model is given by a system of four partial differential equations (PDEs) which for small amplitude wavefront does not produce caustic in the wavefront. The small variations in sound speed and the corresponding distortion of the rays due to nonlinearity are included in the system of PDEs. Rays are given as the orthogonal trajectories to the wavefront and, because of the nonlinearity effects of the media, rays are not straight lines. We represent the wavefront by a discrete set of points, and then we propagate each point along orthogonal trajectories with sound speed determined by a discretized set of two PDEs relating Mach number and area of the ray tube. The numerical results obtained using the above procedure is compared with exact numerical solutions and experimental data given by other authors.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
An agent-based simulation model to study accountable care organizations

Creating accountable care organizations (ACOs) has been widely discussed as a strategy to control rapidly rising healthcare costs and improve quality of care; however, building an effective ACO is a complex process involving multiple stakeholders (payers, providers, patients) with their own interests. Also, implementation of an ACO is costly in terms of time and money. Immature design could cause safety hazards. Therefore, there is a need for analytical model-based decision-support tools that can predict the outcomes of different strategies to facilitate ACO design and implementation. In this study, an agent-based simulation model was developed to study ACOs that considers payers, healthcare providers, and patients as agents under the shared saving payment model of care for congestive heart failure (CHF), one of the most expensive causes of sometimes preventable hospitalizations. The agent-based simulation model has identified the critical determinants for the payment model design that can motivate provider behavior changes to achieve maximum financial and quality outcomes of an ACO. The results show nonlinear provider behavior change patterns corresponding to changes in payment model designs. The outcomes vary by providers with different quality or financial priorities, and are most sensitive to the cost-effectiveness of CHF interventions that an ACO implements. This study demonstrates an increasingly important method to construct a healthcare system analytics model that can help inform health policy and healthcare management decisions. The study also points out that the likely success of an ACO is interdependent with payment model design, provider characteristics, and cost and effectiveness of healthcare interventions.
Auxilin is essential for Delta signaling

Endocytosis regulates Notch signaling in both signaling and receiving cells. A puzzling observation is that endocytosis of transmembrane ligand by the signaling cells is required for Notch activation in adjacent receiving cells. A key to understanding why signaling depends on ligand endocytosis lies in identifying and understanding the functions of crucial endocytic proteins. One such protein is Epsin, an endocytic factor first identified in vertebrate cells. Here, we show in Drosophila that Auxilin, an endocytic factor that regulates Clathrin dynamics, is also essential for Notch signaling. Auxilin, a co-factor for the ATPase Hsc70, brings Hsc70 to Clathrin cages. Hsc70/Auxilin functions in vesicle scission and also in uncoating Clathrin-coated vesicles. We find that like Epsin, Auxilin is required in Notch signaling cells for ligand internalization and signaling. Results of several experiments suggest that the crucial role of Auxilin in signaling is, at least in part, the generation of free Clathrin. We discuss these observations in the light of current models for the role of Epsin in ligand endocytosis and the role of ligand endocytosis in Notch signaling.
Anchoring the gas-phase acidity scale: From formic acid to methanethiol

Abstract We have measured the gas-phase acidities of nine compounds: formic acid, acetic acid, 1,3-propanedithiol, 2-methyl-2-propanethiol, 3-methyl-1-butanethiol, 2-propanethiol, 1-propanethiol, ethanethiol, and methanethiol, with acidities ranging from 338.6 to 351.1 kcal mol −1 using proton transfer kinetics and the resulting equilibrium constants. These acids were anchored to the well-known acidity of hydrogen sulfide; the measured acidities are in good agreement with previous experimental values, but error bars are significantly reduced. The gas-phase acidity of 3-methyl-1-butanethiol was determined to be 347.1 (5) kcal mol −1 ; there were no previous measurements of this value. Entropies of deprotonation were calculated and enthalpies of deprotonation were determined.
Measurement of Proton Electromagnetic Form Factors at High Momentum Transfers

Elastic electron-proton scattering cross sections have been measured using the internal beam of the 6-BeV Cambridge Electron Accelerator at laboratory scattering angles between 31\ifmmode^\circ\else\textdegree\fi{} and 90\ifmmode^\circ\else\textdegree\fi{} for values of the four-momentum transfer squared ranging from ${q}^{2}=0.389 \mathrm{to} 6.81$ ${(\mathrm{B}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$ (${q}^{2}=10 \mathrm{to} 175$${\mathrm{F}}^{\ensuremath{-}2}$). Incident electron energies ranged from 1.0 to 6.0 BeV. Scattered electrons from an internal liquid-hydrogen target were momentum-analyzed using a single quadrupole spectrometer capable of momentum analysis up to 3.0 BeV/c. \ifmmode \check{C}\else \v{C}\fi{}erenkov and shower counters were used to help reject pion and low-energy background. The cross sections presented are absolute cross sections with experimental errors ranging from 6.8% to 20%. Separation of proton electromagnetic form factors have been made for all but the two highest momentum transfer points, using the Rosenbluth formula. Both form factors, ${G}_{\mathrm{Ep}}$ and ${G}_{\mathrm{Mp}}$, were observed to continue to decrease as the momentum transfer increases. An upper limit to the possible asymptotic values of the proton electromagnetic form factors has been established.
A spatially explicit model simulating western corn rootworm (Coleoptera: Chrysomelidae) adaptation to insect-resistant maize

A stochastic spatially explicit computer model is described that simulates the adaptation by western corn rootworm, Diabrotica virgifera virgifera LeConte, to rootworm-resistance traits in maize. The model reflects the ecology of the rootworm in much of the corn belt of the United States. It includes functions for crop development, egg and larval mortality, adult emergence, mating, egg laying, mortality and dispersal, and alternative methods of rootworm control, to simulate the population dynamics of the rootworm. Adaptation to the resistance trait is assumed to be controlled by a monogenic diallelic locus, whereby the allele for adaptation varies from incompletely recessive to incompletely dominant, depending on the efficacy of the resistance trait. The model was used to compare the rate at which the adaptation allele spread through the population under different nonresistant maize refuge deployment scenarios, and under different levels of crop resistance. For a given refuge size, the model indicated that placing the nonresistant refuge in a block within a rootworm-resistant field would be likely to delay rootworm adaptation rather longer than planting the refuge in separate fields in varying locations. If a portion of the refuge were to be planted in the same fields or in-field blocks each year, rootworm adaptation would be delayed substantially. Rootworm adaptation rates are also predicted to be greatly affected by the level of crop resistance, because of the expectation of dependence of functional dominance on dose. If the dose of the insecticidal protein in the maize is sufficiently high to kill >90% of heterozygotes and ≈100% of susceptible homozygotes, the trait is predicted to be much more durable than if the dose is lower. A partial sensitivity analysis showed that parameters relating to adult dispersal affected the rate of pest adaptation. Partial validation of the model was achieved by comparing output of the model with field data on population dynamics, and with field data documenting rootworm adaptation to cyclodienes and organophosphates.
Diagnosing coupled jet-streak circulations for a northern plains snow band from the operational nested-grid model

On 17 March 1989, moderate to heavy snow developed in a 100- to 200-km-wide band extending from South Dakota to northern Michigan. The 4- to 8-inch snowfall within this band was not associated with major cyclogenesis, and developed 500 to 600 km north of a stationary surface front. A diagnostic analysis based on an application of the General Meteorological Package (GEMPAK 5.0) to a numerical simulation from the operational nested-grid model (NGM) is utilized to show that the development of this snow band is related to the interaction of two upper-tropospheric jet streaks and their associated transverse circulation patterns. The eastward propagation of a jet streak from the West Coast toward the middle United States and to the south of a slower-moving jet along the U.S.-Canadian border led to a merger of the ascent maxima associated with the direct and indirect circulations of the northern and southern jets, respectively. The snow band developed as the ascending branches of the jet-streak circulation patterns merged, with the eastward propagation of the heaviest snow linked to the motion of the coupled circulation pattern. The study also demonstrates the usefulness of the operational NGM for providing the higher-resolution datasets required to relate the evolution of jet-streak circulation patterns to the development of mesoscale precipitation bands.
Transforming chronic illness care education: A longitudinal interprofessional mentorship curriculum

Despite the growing burden of chronic disease globally, a number of reports have documented the failure of our health care systems to provide quality care for patients with chronic illness. Interpr...
Will self-calibration work in the infrared?

Throughout the 1980's the Infrared Group of the Optical Sciences Center at the University of Arizona has participated in the national and international efforts to realize self-calibration of photodetectors in the infrared. The results have not been encouraging.
CORRELATION OF DIGOXIN-TABLET DISSOLUTION-RATE WITH BIOLOGICAL AVAILABILITY

Abstract Twelve lots of digoxin tablets from eight American companies were studied in vivo and in vitro. Biological availability was tested in normal human subjects after single 0·5 mg. doses and in the steady state after 8-10 days of drug administration. Excellent correlations were observed between dissolution-rate in 0·6% hydrochloric acid and bioavailability. Variation in digoxin bioavailability appears to result from differences in the rate at which the tablets go into solution in the gastrointestinal tract. It is recommended that a lower limit of acceptability for dissolution-rate be established for digoxin tablets to be used in patients.
Auditory temporal processes in normal-hearing individuals and in patients with auditory neuropathy☆

Abstract Objective To study objectively auditory temporal processing in a group of normal hearing subjects and in a group of hearing-impaired individuals with auditory neuropathy (AN) using electrophysiological and psychoacoustic methods. Methods Scalp recorded evoked potentials were measured to brief silent intervals (gaps) varying between 2 and 50 ms embedded in continuous noise. Latencies and amplitudes of N100 and P200 were measured and analyzed in two conditions: (1) active, when using a button in response to gaps; (2) passive, listening, but not responding. Results In normal subjects evoked potentials (N100/P200 components) were recorded in response to gaps as short as 5 ms in both active and passive conditions. Gap evoked potentials in AN subjects appeared only with prolonged gap durations (10–50 ms). There was a close association between gap detection thresholds measured psychoacoustically and electrophysiologically in both normals and in AN subjects. Conclusions Auditory cortical potentials can provide objective measures of auditory temporal processes. Significance The combination of electrophysiological and psychoacoustic methods converged to provide useful objective measures for studying auditory cortical temporal processing in normals and hearing-impaired individuals. The procedure used may also provide objective measures of temporal processing for evaluating special populations such as children who may not be able to provide subjective responses.
DIAGNOSTIC EVALUATION IN GASTROESOPHAGEAL REFLUX DISEASE

Gastroesophageal reflux disease (GERD) describes the clinical manifestations of reflux of gastric contents and the associated of symptoms and patterns of tissue injury. Although its exact prevalence is difficult to determine, there is no doubt that GERD is the most common esophageal disease and probably among the most prevalent conditions seen in the primary care setting. Heartburn has been noted to occur on a daily or monthly basis in 7% or 36% of control subjects responding to a questionnaire. 74 A population based study using a validated questionnaire found that heartburn, acid regurgitation, or both are experienced at least weekly in 19.8% and on an intermittent basis in 58.7% of respondents. 64 GERD can lead to chronic symptoms and can have a detrimental impact on quality of life more profound than that seen with other conditions, including duodenal ulcer, mild angina, untreated hypertension, and menopause. 19 The impact of GERD is noted in particular on measures of pain, mental health, and social function. 81 GERD has diverse clinical manifestations (Fig. 1). Patients can present with esophageal symptoms with or without evidence of esophageal mucosal damage and with or without evidence of quantifiable pathologic acid reflux. Other patients may have esophageal mucosal damage and complications of reflux with or without symptoms. Yet other patients may have no or few esophageal symptoms and present with a variety of extraesophageal manifestations. These patients with extraesophageal manifestations typically lack overt esophageal damage. Because of this wide clinical spectrum, the diagnostic evaluation of GERD can be difficult and challenging. The evaluation begins with a thorough medical history focusing on esophageal as well as extraesophageal symptoms. It is critical to understand fully the spectrum of GERD to use most appropriately the diagnostic testing available. These testing modalities include endoscopy and biopsy, pH monitoring, radiologic studies such as barium studies and scintigraphy, provocative studies, and esophageal manometry as well as using a trial of acid-suppressive therapy as a diagnostic test. Each of these modalities has inherent advantages and limitations, and there is no absolute or gold standard for the diagnosis of GERD. Each modality, however, can assess a different dimension of GERD, and as such, different modalities can be complementary in the evaluation of a particular patient. Because of the clinical diversity, the decision to recommend any diagnostic test depends on the particular patient problem and on the question to be answered. This article reviews the signs and symptoms of GERD and the diagnostic testing strategies to optimize the evaluation of patients with suspected GERD.
Gel Kinetic Analysis of DNA Polymerase Fidelity in the Presence of Proofreading Using Bacteriophage T4 DNA Polymerase (

A gel fidelity assay, previously used in the analysis of DNA polymerases having no associated 3' to 5' exonuclease activity, has been generalized for use with polymerases that contain exonucleolytic proofreading. The main purpose of this study was the development of a general analysis, using a standard Markov model, to convert experimentally observed DNA primer gel bands arising from insertion and proofreading of right and wrong deoxyribonucleotides, into nucleotide incorporation velocities and, most importantly, fidelities. The model has been applied primarily to an analysis of polymerase kinetics and fidelity in the presence of a next correct rescue dNTP, but the model can be conveniently modified to investigate other experimental designs. In the presence of rescue dNTP, direct competition occurs between excision or extension of a mismatch. At concentrations of rescue dNTP sufficient to suppress the gel band intensity at the mismatch target site, nucleotide incorporation and misincorporation rates can be obtained from the ratios of gel band intensities 3' (downstream) and 5' (upstream) to the target site, measured as a function dNTP concentration for "wrong" and "right" dNTP substrates. The polymerase misincorporation efficiency, in the presence of proofreading, is given by the ratio of wrong to right incorporation efficiencies, Vmax/Km, obtained from the gel band ratios. The bacteriophage T4 polymerase with a highly active 3'-exonuclease activity was used to illustrate the assay. Nucleotide misincorporation efficiencies measured at several template sites were dCMP.A approximately equal to 10(-6), dGMP.A approximately equal to 10(-5), dTMP.T approximately equal to 2 x 10(-4), and dAMP.A < 10(-7). Proofreading of the dGMP.A mispair was suppressed by about 3-fold in the presence of high concentrations of next correct "rescue" dNTP causing a concomitant reduction in the fidelity of dGMP.A to about 3 x 10(-5).
Physical Activity and Incidence of Atrial Fibrillation in Older Adults: The Cardiovascular Health Study.

Retrospective case-control studies and case series of younger athletes and middle-aged adults have suggested an adverse association between physical activity and development of atrial fibrillation. However, these studies have evaluated subjects engaged in either vigorous exertion or endurance training. On the other hand, habitual physical activity might be expected through salutatory effects on blood pressure, vascular compliance, coronary disease, and heart failure to reduce the incidence of atrial fibrillation in the general population. The aim of this study was to assess the effect of habitual light to moderate physical activity on the incidence of atrial fibrillation among older adults.
A Research Update on Correlates of Heavy Episodic Drinking Among Undergraduate College Students

BackgroundDespite prevention efforts of colleges and universities across the nation, there have been no substantial decreases in heavy episodic drinking among undergraduates over the past 2 decades.PurposeThis study provides an update on correlates of heavy episodic drinking for a recent cohort of undergraduate college students.MethodsA cross-sectional survey design was utilized. Participants were randomly selected undergraduate students from a public 4-year university located in the Northeast.ResultsHeavy episodic drinking was associated with male gender, white race, having a family history of drug or alcohol abuse, smoking cigarettes, and using marijuana. Age, athlete status, completion of an alcohol education program, condom use, depression, anxiety, and financial stress were not associated. After controlling for gender and race, marijuana use and smoking cigarettes were found to increase predictability of heavy episodic drinking.DiscussionRates of heavy episodic drinking remain high but correlates may...
Comparison of dressing removal following hypospadias repair

Hypospadias occurs when the urethral folds fail to fuse on the ventral aspect of the penis (Thomas and Barker, 1997). Surgical repair is often warranted and standard postoperative practice in the UK often includes the application of a dressing around the penis. This article reports the outcome of a small randomized controlled feasibility study to compare two methods of dressing removal following hypospadias repair. The same dressing was used throughout the study — a control group used a standard method of dressing removal, while an experimental group had an additional barrier film applied before the dressing was attached to the wound. The primary outcome measure was the time taken to remove the dressing. The time interval between starting the process of dressing removal and having no dressing left in place was used for statistical analysis. Secondary measures included assessment of the child's pain at different intervals by the parents and by an independent nurse observer. General discussion took place wi...
Seeing Mt. Rainier: Lucky imaging for multi-image denoising, sharpening, and haze removal

Photographing distant objects is challenging for a number of reasons. Even on a clear day, atmospheric haze often represents the majority of light received by a camera. Unfortunately, dehazing alone cannot create a clean image. The combination of shot noise and quantization noise is exacerbated when the contrast is expanded after haze removal. Dust on the sensor that may be unnoticeable in the original images creates serious artifacts. Multiple images can be averaged to overcome the noise, but the combination of long lenses and small camera motion as well as time varying atmospheric refraction results in large global and local shifts of the images on the sensor. An iconic example of a distant object is Mount Rainier, when viewed from Seattle, which is 90 kilometers away. This paper demonstrates a methodology to pull out a clean image of Mount Rainier from a series of images. Rigid and non-rigid alignment steps brings individual pixels into alignment. A novel local weighted averaging method based on ideas from “lucky imaging” minimizes blur, resampling and alignment errors, as well as effects of sensor dust, to maintain the sharpness of the original pixel grid. Finally, dehazing and contrast expansion results in a sharp clean image.
A dual-channel fiber optic displacement probe for structural power flow measurements

Abstract A two-channel fiber optic displacement probe is examined to determine its performance characteristics as a vibration sensor for use in performing structural power flow measurements. Its amplitude sensitivity and phase' response are determined and compared with those of more traditional sensors, including accelerometers, eddy current probes and capacitance gauges. Structural power flow measurements are made using a vibrating beam set-up to compare the performance of the fiber optic probe with that of a linear array of accelerometers. The results of the test indicate that the optical probes possess operating parameters at least as good as those of the other sensors tested, and are accurate to within 8.5% in measuring the structural power flow.
Assessment of two external telemetry systems (PhysioJacket and JET) in beagle dogs with telemetry implants.

Abstract Introduction Regulatory guidelines recommend the use of conscious, unrestrained animals for comprehensive cardiovascular safety assessment of a new therapeutic agent. Cardiovascular safety pharmacology studies normally use internal telemetry (surgical implants) in free-moving animals to monitor key ECG endpoints, like the QTc interval, but this technical approach is highly resource intensive. In toxicology studies, ECG recording is also typically performed under chemical or physical restraint, which has a number of disadvantages, e.g., anesthesia confounds, handling stress and limited data collection. External telemetry for ECG recording has the potential to overcome many of these restraint limitations, with the benefit of being a surgically non-invasive method. To evaluate this method, we used two jacket systems: Data Sciences International (DSI) JET™ and Integrated Telemetry Systems (ITS) PhysioJacket™ in implanted beagle dogs. Methods Heart rate and cardiac intervals were monitored continuously for 22–24 h following oral administration of vehicle (water) or 1 mg/kg E-4031. Data obtained from each jacket system was compared with implant-derived data in the same animal. Results Significant increases in QT/QTcV (25–30 ms) were noted following treatment with 1 mg/kg E-4031 in both external jacket systems and with implanted telemetry. Throughout the recording periods, the normal variations in heart rate and ECG intervals observed in conscious dogs as detected with the jacket systems, mirrored the changes observed via implant telemetry. Discussion The overall findings from this study support the use of external telemetry technology as a viable alternative to implants. The data demonstrated that jackets were sufficiently sensitive to detect QT/QTcV changes following E-4031 administration, that were comparable to those derived from implants. As such, this method is an invaluable tool for obtaining high quality ECG data from repeat-dose toxicology studies.
DIAPHOTOTROPIC MOVEMENT OF THE LEAVES OF MALVA NEGLECTA

THE FACT that the leaves of some plants orient themselves perpendicularly to the incident light has been known for a long time. Among the first to observe the phenomenon were Bonnet (1754) and Dutorchet (1833). Later it was studied by Frank (1870) who gave it the name " transverse heliotropism." Frank thought that light was the causative agent for the movement, but de Vries (1874) believed that several factors working together were responsible-e.g., geotropism, epinasty and hvponasty, and weight of the leaves. The question was settled in favor of Frank's hypothesis by the work of Darwin (1881) and V16chting (1888). Darwin also proposed the name " diaphototropism " which has since been in general use. In the beginning of the present century attention was directed to the question of the perception of light by leaves. Haberlandt (1905) founded the lens-action hypothesis which was later disproved by the work of Kniep. Diaphototropic movements can be observed in the leaves of many plants, chiefly Leguminosae and in flower heads such as the sunflower. They are often mentioned in connection with ecological studies. The physiological side of the question has not been studied except by V6chting (1888) and Denecke (1924). Vdchting made many interesting observations, the results of which will be discussed later. Denecke was chiefly concerned with the perception of light. His results were of little value as he failed to distinguish clearly diaphototropic movement from other movements of the leaves. As far as is known to the writer diaphototropic movement has not yet been carefully analyzed, and its mechanism remains obscure. In the present study the leaves of Malva neglecta were used. Beside exhibiting the daily diaphototropic movement, these leaves also showed a number of other movements such as epinasty, geotropism and phototropism of the petiole, and sometimes sleeping movements. To avoid confusion it seems necessary at the outset to define the diaphototropic movement: it is the orientation of leaves in such a way that the upper faces of the laminae place themselves perpendicular to the incident light. In fact, the leaves are so sensitive that they, as described by Bonnet, " suivent en quelque sorte le cours du soleil: en sorte que le matin ces feuilles regardent le levant; vers le milieu du jour, le midi; le soir, le couchant " (see VYchting, 1888). The present paper attempts: (1) to determine the directive action of light, (2) to differentiate the organs of perception and reaction, and (3) to discover the mechanism of the movement. EFFECT OF LIGHT ON THE MOVEMENT. Observatons under norrmal light conditions.: Young Malva
A Markov Chain Monte Carlo Analysis of the Effect of Two-Rate Property Taxes on Construction☆

Abstract The paper examines the effect of taxing structures at a lower rate than land on the level of construction in 15 Pennsylvania municipalities between 1972 and 1994. These municipalities are compared with 204 similar Pennsylvania municipalities that tax land and structures at the same rate. To reduce the standard errors of estimate below those of a quasi-maximum likelihood estimation, the model parameters are estimated with a Markov chain Monte Carlo method, the Gibbs sampler. In contrast to earlier tax analyses, the estimates indicate that cities with two-rate taxes enjoy significantly higher levels of construction than they would with one-rate taxes.
Economics, ethics, and tort remedies: The emerging concept of hedonic value

This article reviews the development of hedonic value of life as a remedy in wrongful death and personal injury tort cases. Hedonic value estimates the worth of lost pleasures of living in an effort to compensate for intangible enjoyments, such as quality of education and environmental standards. This remedy goes well beyond the traditional approach which has compensated primarily for lost earnings and other expenses directly related to the tortious conduct. Most of the attention regarding hedonic value as a relatively new tort remedy has focused on its application in non-business litigation. However, given the significant damage awards in recent cases, it is likely that this economic theory will arise in commercial litigation, especially products liability cases. The business community must be conversant with the ethical issues raised by this novel tort remedy in order to fashion a reasoned and socially acceptable contra-position.
Potential Pathways to Restore β-Cell Mass: Pluripotent Stem Cells, Reprogramming, and Endogenous Regeneration

Currently available β-cell replacement therapies for patients with diabetes, including islet and pancreas transplantation, are largely successful in restoring normal glucose metabolism, but the scarcity of organ donors restricts their more widespread use. To solve this supply problem, several different strategies for achieving β-cell mass restoration are being pursued. These include the generation of β cells from stem cells and their subsequent transplantation, or regeneration-type approaches, such as stimulating endogenous regenerative mechanisms or inducing reprogramming of non-β cells into β cells. Because these strategies would ultimately generate allogeneic or syngeneic β cells in humans, the control of alloimmunity and/or autoimmunity in addition to replacing lost β cells will be of utmost importance. We briefly review the recent literature on these three promising strategies toward β-cell replacement or restoration and point out the major issues impacting their translation to treating human diabetes.
Tinsel-type Structure in Flagella of Zoospores associated with Cabbage Clubroot Tissue

PARTIALLY disintegrated clubbed roots of cabbage grown in the greenhouse in soil infested with Plasmodiophora brassicae Wor. were stored in a frozen condition for several weeks. They were then macerated in distilled water and much of the coarse debris was removed by filtration of the suspension through several layers of cheesecloth. This was followed by centrifugation at 4,000 r.p.m. for 15 min. and resuspension in sterile distilled water. Centrifugation was repeated three times and after the final one spores were suspended in the nutrient solution described by Macfarlane1, or in autoclaved tap water in sterile 10 × 75 mm. culture tubes plugged with cotton. Tubes were incubated in the dark at 24° C. or at room temperature. Droplets were examined periodically under a Bausch and Lomb phase-contrast microscope for the presence of motile cells.
O16.3 Controlling Chlamydia: Population Modeling to Assess Promising Interventions

Background Chlamydia is an important public health problem associated with neonatal sequelae, pelvic inflammatory disease, infertility, and ectopic pregnancy. Methods Using a population model with 2 genders and ages 15–44 years in 5-year groups, but only heterosexual contacts, we evaluated the impact of actual and hypothetical interventions on chlamydia in the U.S. Parameters were obtained from the literature or estimated from the National Health and Social Life Survey and Seattle Sex Survey. The model was calibrated by adjusting gender-specific probabilities of infection on contact. We calculated the basic reproduction number (R 0 ), defined as the average number of secondary infections per infectious person in a wholly-susceptible population without interventions. We also calculated the age- and gender-specific equilibrium prevalence and contributions to R 0 . And we assessed the impact of interventions by comparing reproduction numbers with and without them. To assess the feasibility of opportunistic screening, we analysed Market Scan, a commercial health insurance database, to determine the proportion of people seeking medical care. Results Treating symptomatic men and women who seek care and screening 38% of women aged 15–24 years during annual examinations more than halve the reproduction number. The equilibrium age- and gender-specific prevalence of infection match those observed in the National Health and Nutrition Examination Survey. Men cause more secondary infections than women (contributing twice as much to R 0 in some age groups), and people aged 25–29 years cause as many as those aged 20–24. Analysis of the Market Scan database indicates that insured men seek care often enough for screening to have substantial impact. Screening women reduces the reproduction number by 3%; screening a similar proportion of young men would reduce it another 4%. Conclusions Our modelling suggests that screening men as well as women and extending the upper age to 29 years may affect chlamydia transmission or sequelae.
Visualizing Particle-in-a-Box Wavefunctions Using Mathcad

Using the built-in differential equation solvers and the graphical capabilities of Mathcad, students can visualize the wavefunctions of the particle-in-a-box potential.
Long-term results of conformal radiotherapy for progressive airway amyloidosis.

Purpose To evaluate the efficacy of conformal external beam radiotherapy (RT) for local control of progressive airway amyloidosis. Methods and Materials We conducted a retrospective review of patients with biopsy-proven progressive airway amyloidosis treated with conformal RT between 2000 and 2006 at Boston Medical Center. The patients were evaluated for performance status and pulmonary function, with computed tomography and endoscopy after RT compared with the pretreatment studies. Local control was defined as the lack of progression of airway wall thickening on computed tomography imaging and stable endobronchial deposits by endoscopy. Results A total of 10 symptomatic airway amyloidosis patients (3 laryngeal and 7 tracheobronchial) received RT to a median total dose of 20 Gy in 10 fractions within 2 weeks. At a median follow-up of 6.7 years (range, 1.5–10.3), 8 of the 10 patients had local control. The remaining 2 patients underwent repeat RT 6 and 8.4 months after initial RT, 1 for persistent bronchial obstruction and 1 for progression of subglottic amyloid disease with subsequent disease control. The Eastern Cooperative Oncology Group performance status improved at a median of 18 months after RT compared with the baseline values, from a median score of 2 to a median of 1 ( p = .035). Airflow (forced expiratory volume in 1 second) measurements increased compared with the baseline values at each follow-up evaluation, reaching a 10.7% increase ( p = .087) at the last testing (median duration, 64.8 months). Acute toxicity was limited to Grade 1-2 esophagitis, occurring in 40% of patients. No late toxicity was observed. Conclusions RT prevented progressive amyloid deposition in 8 of 10 patients, resulting in a marginally increased forced expiratory volume in 1 second, and improved functional capacity, without late morbidity.
The guanosine 5'-diphosphate D-mannose: guanosine 5'-diphosphate L-galactose epimerase of Chlorella pyrenoidosa. Chemical synthesis of guanosine 5'-diphosphate L-galactose and further studies of the enzyme and the reaction it catalyzes.

An enzyme from extracts of the green alga Chlorella pyrenoidosa that catalyzes the reversible epimerization of guanosine 5′-diphosphate d-mannose to guanosine 5′-diphosphate l-galactose was further purified. The substrate guanosine 5′-diphosphate l-galactose was made chemically by the morpholidate procedure. An improved method was developed for the synthesis of an intermediate in that process, β-l-galactopyranosyl phosphate, via an orthoester of l-galactose. Various characteristics of the enzyme and the reaction it catalyzes were studied. A new method using gas-liquid chromatography was introduced for following the course of the reaction with unlabeled substrates.
Roadside, Urban, and Rural Comparison of Primary and Secondary Organic Molecular Markers in Ambient PM2.5

PM2.5 filter samples (12-h and 24-h) were collected in urban Atlanta, GA, next to a freeway and 400 m away, as well as at a rural site, with particular focus on exploring on-road emissions, regional transport, and biogenic effects. Detailed speciation of PM2.5 carbonaceous aerosols was conducted by GC/MS. Diurnal, seasonal, and spatial variations of PM2.5 organic composition were investigated. Primary organic compounds usually exhibit different attributes of day vs night while secondary organic tracers varied little. Much higher concentrations of automotive-related primary organic compounds are observed at the highway site, including n-alkanes, hopanes, steranes, and polycyclic aromatic hydrocarbons (PAHs). Season-specific on-road mobile source primary OC profiles were developed by using differences in organic species concentrations between the highway site and the nearby site. Calculated on-road source profiles differ from mobile source profiles measured in the lab. Significant seasonal differences are o...
Synthesis of Polyethylene-g-polystyrene and Polyethylene-g-poly(p-methylstyrene) Graft Copolymers

This paper describes a new method to prepare polyethylene graft copolymers, such as polyethylene-g-polystyrene and polyethylene-g-poly(p-methylstyrene), with a relatively well-controlled reaction mechanism. The chemistry involves a transformation process from the metallocene copolymerization of ethylene and p-methylstyrene to the anionic living polymerization of styrene or p-methylstyrene. The metallocene catalysis produces poly(ethylene-co-p-methylstyrene) random copolymers with molecular weight distribution (Mw/Mn) of about 2.5. The following selective metalation reaction of p-methylstyrene units in the copolymer and the subsequent anionic “living” graft-from polymerization were effective to produce polymeric side chains with well-defined structure. Both graft density and graft length can be controlled by p-methylstyrene content in the PE backbone, metalation reagent, and the quantity of monomer used in the graft-from reaction. In the bulk, the individual PE and PS segments in the graft copolymers are...