cssi/SciSciGPT-SciSciNet huggingface dataset:
Comparison of Commercial Fertilizer and Organic By-Products on Soil Chemical and Biological Properties and Vegetable Yields

Organic wastes may substitute for commercial fertilizers and enhance soil chemical and biological properties. This study compared the effects of commercial fertilizer and organic wastes on soil properties and crop yields on three organic and three conventional vegetable farms in Virginia and Maryland. The organic farms produced sweet corn and the conventional farms produced muskmelon or watermelon in 1996. Commercial N, P and K fertilizers were applied according to Virginia Cooperative Extension (VCE) recommendations. The organic fertility sources, composted cotton gin trash (3 farms), composted yardwaste and livestock manure (2 farms), or beef manure (1 farm), were applied to meet the N needs of each crop according to estimated N mineralization rates of the waste after subtracting estimated cover crop N contributions. The concentrations of most nutrients and soil pH, organic matter, and total C were higher after amending with organic wastes than fertilizer. Populations of Trichoderma and thermophilic microorganisms, known antagonists of pathogenic soilborne fungi, were initially greater in the organically-managed soils, and Trichoderma was higher in organic waste-amended than commercially-fertilized soils at harvest. The beneficial species Trichoderma and Pseudomonas were higher and plant pathogenic oomycete fungi were lower in the organic waste-amended than the commercially-fertilized soils regardless of cultural history. The plant pathogenic fungi increased with time and were greater in plots treated with inorganic fertilizers than organic amendments at harvest. Beneficial soil microorganisms appear to be favored by long term organic amendments, but some groups can be increased with organic amendments within a single season. Yields were similar between treatments, which demonstrates that organic amendments can provide adequate amounts of required plant nutrients in addition to enhancing soil chemical and biological attributes.
A formal theory of multiple agent nonmonotonic reasoning

This paper presents a formal theory of multiple agent non-monotonic reasoning. We introduce the subject of multiple agent non-monotonic reasoning for inquiry and motivate the field in terms of its applications for commonsense reasoning. We extend Moore's [1985] Autoepistemic Logic to the multiple agent case, and show that the resulting logic is too weak for most applications of commonsense reasoning. We then suggest some possible sets of principles for a logic of multipleagent non-monotonic reasoning, based on the concept of an agent's arrogance towards his knowledge of another agent's ignorance. While the principles of arrogance are in general too strong, we demonstrate that restricted versions of these principles can work quite well for commonsense reasoning. In particular, we show that a restricted form of the principle of arrogance yields results that are equivalent to EMAT [Morgenstern, 1989], a non-monotonic logic which was designed to reason about temporal projection in epistemic contexts.
Patterns of Storage, Use, and Disposal of Prescription Opioids by Parents of Children With Cancer.

Abstract Context Multiple studies have demonstrated that adults do not store prescription opioids safely. Increased prescription opioid rates have led to an increased incidence of opioid poisonings in children and adolescents. Objectives We investigated whether parents practiced safe storage, use, and disposal techniques of opioids that were prescribed to their child with cancer-related pain. Methods We conducted a prospective cross-sectional survey of parents whose children were prescribed opioids and asked them about their patterns of storage, use, and disposal of prescription opioids. Results Virtually, all parents (106 of 109; 97%) completed the survey. Most parents (95 of 106; 90%) did not store opioids safely. Six of 106 parents (6%) gave their child's opioid pain medication to someone else with pain, and three of 106 parents (3%) personally took some of their child's opioid. Parents who personally took their child's opioid (P = 0.01) or gave it to another person (P Conclusion Universal education about the safe use and disposal of opioids should be adopted when prescribing opioids. Pediatricians need to maintain vigilance about the nonmedical use of prescription opioid use by parents of children.
A re-evaluation of the feature coronal

Abstract This paper compared and contrasted the Chomsky and Halle feature “coronal” with the Jakobson, Halle, and Fant feature “grave”, particularly as these features characterize palatal and palato-alveolar consonants. The feature coronal separates palato-alveolar from palatal consonants, whereas the feature grave classifies them together. Based primarily on phonological evidence from various languages, we conclude that the palatal and palato-alveolar places of articulation never contrast phonologically within the stop manner class. Instead, phonological contrasts are found only between palato-alveolar affricates and palatal stops. Thus, manner alone can distinguish between the non-continuants occurring in these places of articulation. In the case of fricatives, stridency can distinguish the palatals from the palato-alveolar fricatives. These results question the original classification schema and resulting contrasts of the feature “coronal”, and suggest that this feature needs to be revised with the same attributes as the feature “grave”.
Identifying a Coefficient Matrix for Numerical Approximations to the Wave Equation in Two Dimensions

In this paper we develop a coefficient matrix to be used in numerical approximation methods which model the wave equation in two dimensions. In particular, we will briefly introduce the centered difference approximation method. Next, we explain the derivation of the system of equations into which the problem is transformed in order to utilize such a method. Then, we introduce a set of rules to generate the generalized coefficient matrix for use in approximating the wave equation for any number of unknowns per axis. Finally, we write MATLAB code which uses our matrix to solve said approximations, and then use it in a real world application. The desired outcome of this project has been achieved: to generalize the coefficient matrix used in the system of equations which approximates the wave equation in two dimensions so that its algorithm may be used in MATLAB code for any number of unknowns. Acknowledgements: The author would like to thank Dr. Jangwoon Lee for his guidance. RHIT Undergrad. Math. J., Vol. 16, No. 1 Page 153
Candidate silencer elements for the human and mouse genomes

The study of gene regulation is dominated by a focus on the control of gene activation or increase in the level of expression. Just as critical is the process of gene repression or silencing. Chromatin signatures have identified enhancers, however, genome-wide identification of silencers by computational or experimental approaches are lacking. Here, we first define uncharacterized cis-regulatory elements likely containing silencers and find that 41.5% of ~7500 tested elements show silencer activity using massively parallel reporter assay (MPRA). We trained a support vector machine classifier based on MPRA data to predict candidate silencers in over 100 human and mouse cell or tissue types. The predicted candidate silencers exhibit characteristics expected of silencers. Leveraging promoter-capture HiC data, we find that over 50% of silencers are interacting with gene promoters having very low to no expression. Our results suggest a general strategy for genome-wide identification and characterization of silencer elements.
Boko Haram, bandits and slave-raiders: identities and violence in a Central African borderland

Boko Haram is a religiously motivated insurgency with a complex history in Nigeria and origins in urban Maiduguri. Through most of its existence Boko Haram has shown an affinity for border regions:...
Shifts in Prescribers' Initial Postoperative Opioid Prescriptions Following Primary Total Hip Arthroplasty Between 2014 and 2018.

BACKGROUND The opioid epidemic is a public health crisis impacting the practice of surgeons performing primary total hip arthroplasty (THA). Seeking to evaluate changes in prescribers' practices, we asked the following questions: (1) Have the initial discharge opioids following THA changed and (2) Have initial total oral morphine milligram equivalents (OME) prescribed following THA decreased since 2014? METHODS We retrospectively reviewed discharge prescriptions for 4233 primary THAs performed between fiscal years (FYs) 2014 and 2018 throughout our healthcare system. Drug, dosing, and total OMEs were recorded. We categorized prescriptions into 3 groups: short-acting narcotics only, short-acting plus long-acting narcotics, and short-acting narcotics plus tramadol. Mean age was 59 and 63% were males. RESULTS The proportion of patients receiving tramadol increased from 2% (FY14) to 25% (FY18) while long-acting opioid prescriptions decreased from 44% (FY14) to 14% (FY18). Oxycodone (82%) was the most common short-acting narcotic. In total, we observed a 27% decrease in initial OME prescribed to a mean of 683 mg (FY18) (P < .0001). Short-acting only protocols had a 19% OME decrease to 589 mg (FY18). Short plus long-acting protocols haed a 23% OME decrease to 939 mg (FY18). Short-acting plus tramadol had an OME of 849 mg (FY18). CONCLUSION Despite a 27% observed decrease in initial OME prescription following THA, the 683 mg mean OME in FY18 was high. Substituting tramadol for a long-acting narcotic failed to have a dramatic clinical impact on decreasing OME. These data suggest that decreasing the number of short-acting narcotic pills is a critical factor in decreasing OME.
Diaphragm Paralysis After Pediatric Cardiac Surgery: An STS Congenital Heart Surgery Database Study.

Background Previous single-center studies of diaphragm paralysis (DP) after pediatric cardiac surgery report incidence of 0.3% to 12.8% and associate DP with respiratory complications, prolonged ventilation and length of stay, and mortality. To better define incidence and associations between DP and various procedures and outcomes, we performed a multicenter study. Methods The Society of Thoracic Surgeons Congenital Heart Surgery Database was queried to identify children who experienced DP after cardiac surgery (2010-2018; 126 centers). Baseline characteristics and postoperative outcomes were compared between patients with and without DP as well as between patients who underwent plication and those who did not. Associations between center volume and center rates of DP and use of plication were also explored. Results A total of 2214 of 191,463 (1.2%) patients experienced DP. Postoperative DP portended worse outcomes, including mortality (5.6% vs 3.5%; P Conclusions DP complicating pediatric heart surgery is rare but portends significantly worse outcomes. One-half of patients underwent plication. Center-level risk-adjusted rates of DP and plication are not associated with case volume. Significant variability in plication practices suggests a target for quality improvement.
Handbook of environmental and ecological statistics

This is an extremely well-composed book, offering an interdisciplinary exposure to the concepts and methods that are very valuable to perform environmental and ecological data analysis. The contrib...
Analyzing the Online Presence of Neurologists in the United States (2793)

Objective: Our study aims to determine the online presence of neurologists in the United States. Background: In our age of technological advancement, patients utilize and refer to online resources when trying to make informed decisions about their healthcare providers. This becomes increasingly important in specialties such as neurology that have a shortage of physicians and where a specialist is difficult to find. However, websites are not routinely updated nor regulated, but nonetheless influence where patients decide to seek medical care. There is a lack of research regarding the online presence of neurologists, and subsequently where information regarding their practice is available for patients to access. Therefore, our study aims to determine the online presence of neurologists in the United States. Design/Methods: The Physicians Compare National Database File from the Center for Medicare Services was used to identify a sample of neurologists in the United States. Then, a Google Custom Search Engine was created to parse the first ten search results for each physician using a set of search parameters. A coded script analyzed the URL contents of each link and placed the search results into one of the following categories: health or hospital system, third-party, social media, academic journal, or other. Results: A total of 13,918 neurologists were included for analysis. Of the 139,180 search results obtained, 20.79% were from hospital or health systems, 71.93% were from uncontrolled third-party websites, 5.15% were from social media sites, 0.4% were from academic journals and 1.73% were from other online sources. Conclusions: The online presence of neurologists is predominantly controlled by third-party websites, many of which are inaccessible to the very physicians they represent. As the field of neurology continues to grow, a great opportunity exists for physicians to expand their digital presence to more accurately reflect their practice and increase their patient base. Disclosure: Dr. Elrahi has nothing to disclose. Dr. Curtis has nothing to disclose. Dr. Bilello has nothing to disclose. Dr. Rai has nothing to disclose.
HPV immunisation: A review of parent and stakeholder attitudes on school-based programmes

Aim: The purpose of this integrative review is to examine the benefits of school-based human papillomavirus (HPV) vaccination programmes in improving overall vaccine education and adherence among t...
Analysis of Credit Score in China’s E-commerce Market

Ecommerce has become the mainstream all around the world. In China, multiple platforms occupy the market of ecommerce. These platforms have different strategies and focus on unalike customers. Most of them use personal credit score as a measurement to reduce the risk of fraud transactions, especially in some second-hand goods platforms. In this paper, the author uses survey to analyze the potential relationship between credit score and frauds, from both the consumer and seller’s sides. Then the author discusses some possible improvements which could be made to adjust the current using credit system used in the online platforms.
Transparency, Contracting Frictions, and Trade: Evidence across Firms

Firms engage in off-the-books activities to avoid taxes and government oversight. We conjecture, however, that hidden transactions also increase a firm’s opacity, which leads to ex ante contracting frictions that may be particularly costly when trading partners have little legal recourse for contract abrogation. We study these tradeoffs using Russian firm- and transaction-level data. Consistent with hidden transactions leading to higher contracting frictions, we show that firms with more off-the-books activities tend to be in low contract intensity industries and are less likely to participate in import/export transactions. Conditional on engaging in international trade, off-the-books firms are more likely to trade in homogeneous products in which quality is easier to identify (JEL D22, D23, D73, F14).
Characterization of the subunit composition and structure of adult human glycine receptors

Summary The strychnine-sensitive pentameric glycine receptor (GlyR) mediates fast inhibitory neurotransmission in the mammalian nervous system. Only heteromeric GlyRs mediate synaptic transmission, as they contain the β subunit that permits clustering at the synapse through its interaction with scaffolding proteins. Here, we show that α2 and β subunits assemble with an unexpected 4:1 stoichiometry to produce GlyR with native electrophysiological properties. We determined structures in multiple functional states at 3.6–3.8 A resolutions and show how 4:1 stoichiometry is consistent with the structural features of α2β GlyR. Furthermore, we show that one single β subunit in each GlyR gives rise to the characteristic electrophysiological properties of heteromeric GlyR, while more β subunits render GlyR non-conductive. A single β subunit ensures a univalent GlyR-scaffold linkage, which means the scaffold alone regulates the cluster properties.
COVID-19 Vaccine Demand and Financial Incentives.

Background Public health experts estimate that only very high COVID-19 vaccine uptake levels can result in herd immunity. Objective This study's main objective was to evaluate the impact of vaccine price levels, including payments, and the efficacy levels on COVID-19 vaccine demand. Methods Data for this study were collected from an online survey of 2000 US individuals aged 18 years and older, which included a set of contingent valuation questions. Parametric and nonparametric procedures were used to estimate the distribution of willingness-to-pay and willingness-to-accept values for the vaccine and to assess its association with vaccine efficacy levels (50, 70, and 95%). Results Most of the individuals (60%) indicated they were willing to pay a positive amount for the vaccine; 13.7% said they would only accept the vaccine if it were free; 14.1% were willing to take the vaccine only if they were paid; and 12.2% were not willing to accept the vaccine. The vaccine efficacy level was found to affect an individual's demand for the vaccine. Estimated mean willingness-to-pay values were: US$594, US$706, and US$723 for vaccines with efficacy levels of 50, 70, and 95%, respectively. Conclusions US individuals highly value the COVID-19 vaccine, and about 88% of the US population would accept the vaccination; however, 14% indicated they would get vaccinated if compensated. Payments of about US$500 or more would be needed to sufficiently incentivize 50% or more of this group vaccinated.
Plants that lead: do some surface features direct enemy traffic on leaves and stems?

Land plants exhibit a wide variety of defences that deter the consumption of leaves and stems, including trichomes (hairs), thorns, and thick cuticles. In many plants, trichomes are hooked or inclined to the leaf or stem surface, and the teeth on leaf margins point either apically or more rarely toward the base. The role of these anisotropic structures as potential defences has been largely ignored. In the present study, it is proposed that apically oriented surface features function as ratchets directing the movements of small herbivores toward the leaf ends and ultimately off the leaf, whereas basally oriented protrusions interfere with the ascent of consumers to the upper parts of the plant. These proposed defencive functions do not exclude other potential benefits of anisotropic features, such as self-cleaning of surfaces. The proposed defencive role of apically oriented trichomes and teeth may represent an unusual class of physical defences that speed up rather than slow down encounters between enemies and their plant victims.
Prevalence of Sodium and Fluid Restriction Recommendations for Patients with Pulmonary Hypertension

Background: Patients with pulmonary hypertension (PH) are often afflicted with the consequences of right heart failure including volume overload. Counseling to assist the patient in the dietary restriction of sodium and fluid may be underutilized. Methods: Consecutive patients seen in the PH Clinic at Mayo Clinic in Florida from June to November 2013. Results: 100 patients were included; 70 were women and most had group 1 PH (n = 69). Patient characteristics using mean (±SD) were: Age 63 ± 13 years, functional class 3 ± 1, brain natriuretic peptide 302 ± 696 pg/mL, 6-min walk 337 ± 116 m, right atrial pressure 8 ± 5 mmHg, and mean pulmonary artery pressure 42 ± 13 mmHg. Overall, 79 had had complete (32) or partial instruction (47) and 21 had no prior counseling to restrict sodium or fluid. Of the 47 with partial instruction, 42 received complete education during the PH Clinic visit. Of the 21 without prior instruction, 19 received complete education during the PH visit. Seven patients with the opportunity to have their education enhanced or provided did not receive any additional counseling during the PH visit. Conclusion: Sodium and fluid restriction is an important but perhaps underutilized strategy to manage volume overload in patients with right heart failure. Focused questioning and education may permit an increase in the patients receiving instruction in this regard.
Computing equilibria in multiplayer stochastic games of imperfect information

Computing a Nash equilibrium in multiplayer stochastic games is a notoriously difficult problem. Prior algorithms have been proven to converge in extremely limited settings and have only been tested on small problems. In contrast, we recently presented an algorithm for computing approximate jam/fold equilibrium strategies in a three-player nolimit Texas hold'em tournament--a very large real-world stochastic game of imperfect information [5]. In this paper we show that it is possible for that algorithm to converge to a non-equilibrium strategy profile. However, we develop an ex post procedure that determines exactly how much each player can gain by deviating from his strategy and confirm that the strategies computed in that paper actually do constitute an e-equilibrium for a very small e (0.5% of the tournament entry fee). Next, we develop several new algorithms for computing a Nash equilibrium in multiplayer stochastic games (with perfect or imperfect information) which can provably never converge to a non-equilibrium. Experiments show that one of these algorithms outperforms the original algorithm on the same poker tournament. In short, we present the first algorithms for provably computing an e-equilibrium of a large stochastic game for small e. Finally, we present an efficient algorithm that minimizes external regret in both the perfect and imperfect information cases.
Clathrin-coated vesicle formation from isolated plasma membranes.

Abstract Endocytic clathrin‐coated vesicle (CCV) formation is a complex process involving a large number of proteins and lipids. The minimum machinery and the hierarchy of the events involved in CCV formation have yet to be defined. Here we describe an in vitro assay for CCV formation from highly purified rat liver plasma membranes. This rapid and easy assay can be used to quantitatively evaluate the different protein requirements for different endocytic receptors.
Prep Plus: Evaluating the Motivations for and Effects of Enrollment Multipliers and Other Measures in High School Sports

In states like Illinois, controversial enrollment multipliers have been implemented. Under Illinois' formula, a "non-boundaried" school will have its actual enrollment multiplied by 1.65 for determining the classification in the State's high school playoff system. This formula is not unique to Illinois; states nationwide have begun to evaluate ways at curbing the disproportionate amount of championships won by private schools. In some of these states, a multiplier system has been implemented while others have used separate playoff systems or drafted proposals limiting the boundaries from which private schools can draw their students.
Lamellate fracture in 5150 steel processed by modified ausforming

An investigation was made of the metallurgical factors responsible for the improved impact resistance of 5150 steel processed by modified ausforming. It was found that if the austenite is unrecrystallized prior to quenching to martensite, a change occurs from a primarily intergranular to a transgranular fracture path. While some increase in impact strength seems associated with this change, the major factor responsible for improved impact strength is lamellate fracture,i.e., blunting of a propagating crack by splitting on planes parallel to the rolling plane. Such fracture is not observed unless banded alloy segregation exists, in which case splitting occurs in a brittle manner along sulfide interfaces in bands of high alloy content. While lamellate fracture produces a marked improvement in longitudinal impact strength, there is a corresponding deterioration of transverse impact properties.
Metabolism of trinitrobenzene sulfonic acid by the rat colon produces reactive oxygen species

Recent studies have shown that intrarectal administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS) in ethanol or intramural injection of TNBS in saline produces an acute and possibly chronic colitis in rats. It has been assumed that interstitial TNBS initiates the inflammatory response via macrophage-mediated recognition and degradation of TNBS-modified mucosal cells and proteins. However, it is known that certain flavoproteins and/or reductants interact with compounds containing the nitro functional group to generate pro-inflammatory, nitrogen-centered free radicals and reactive oxygen metabolites. The objective of this study was to assess the ability of the rat colon, using either colon homogenates, isolated colonocytes, or intestinal interstitial fluid, to produce reactive oxygen species via enzymatic and/or nonenzymatic metabolism of TNBS. It was found that the addition of TNBS (1 mmol/L) to the 10,000 x g supernatant of rat colon homogenates increased the rate of superoxide production from normally undetectable levels to 2.6 +/- 0.23 nmol.min-1.mg protein-1. Addition of nicotinamide adenine dinucleotide, reduced form (NADH; 1 mmol/L) to colon homogenates containing TNBS significantly enhanced superoxide production to 10.4 +/- 0.9 nmol.min-1.mg-1. Similarly, addition of nicotinamide adenine dinucleotide phosphate, reduced form (NADPH; 1 mmol/L) to colon extracts containing TNBS produced an even further increase in the rate of superoxide formation to 25.2 +/- 1.1 nmol.min-1.mg-1. Addition of NADH or NADPH to the colon homogenate in the absence of TNBS produced no detectable superoxide formation, suggesting that TNBS was required for the enhanced oxidative metabolism. In a separate series of experiments, it was found that isolated colonocytes produced small but significant amounts of superoxide (3.15 +/- 0.6 nmol/2 x 10(6) cells) that were significantly increased in the presence of ethanol to 6.55 +/- 1.14 nmol/2 x 10(6) cells. Using purified preparations of two flavoproteins found in the rat colon, it was shown that the addition of TNBS (1 mmol/L) to purified NADH dehydrogenase or glutathione reductase increased the rate of superoxide formation by these enzymes from normally undetectable levels to 1.6 nmol/min and 1.2 nmol/min, respectively. In addition, it was found that intestinal interstitial fluid (lymph) initiated redox cycling of TNBS such that 28.1 +/- 1.6 nmol of oxygen was consumed per minute per milliliter of lymph. This increase in oxygen consumption was inhibited by the addition of superoxide dismutase and catalase. One possible metabolite involved in both mucosal and lymph-mediated metabolism of TNBS is ascorbic acid.(ABSTRACT TRUNCATED AT 400 WORDS)
Contraception and Pregnancy Planning in Women With Congenital Heart Disease

The cardiovascular risk of pregnancy among women with congenital heart disease is heterogeneous, ranging from negligible to prohibitively high. Nonetheless, many of these patients do not report being counseled about the potential risks, and the incidence of unintended pregnancy is high. These women should be counseled on safe and effective contraceptive options. Long-acting reversible contraceptives, including the intrauterine devices and etonogestrel implant, are highly effective and safe for all cardiac patients. These are good options for pregnancy planning for women at elevated risk of cardiovascular complications during pregnancy, who are taking potentially teratogenic medications, or who have contraindications to estrogen-containing methods. Pregnancy management begins with pre-conceptual risk stratification and counseling regarding individual cardiovascular and fetal risks. As significant lapse in care is common at the time of transition to adult congenital cardiology care, these discussions ideally begin in pediatric clinics and continue upon transfer of care to adult congenital cardiology clinics.
Light and Temperature

Solar radiation is vital to the metabolism, indeed to the very existence, of freshwater ecosystems. Nearly all energy that drives and controls the metabolism of lakes and streams is derived from solar energy, which is converted biochemically via photosynthesis to potential chemical energy. The photosynthetic synthesis of organic matter occurs within the lake or river (autochthonous) or within the terrestrial drainage basin (allochthonous) and is transported to the aquatic ecosystem in various forms of dissolved and particulate organic matter by “vehicles” for movement [e.g., air, water, animals; cf., Likens and Bormann (1972)]. In addition to direct biological utilization, the absorption of solar energy and its dissipation as heat markedly affect the thermal structure and stratification of water masses and circulation patterns of lakes, reservoirs, and streams. These characteristics in turn have profound effects on nutrient cycling and the distribution of dissolved gases and the biota. The optical properties of fresh waters, therefore, exert important regulatory controls on the physiology and behavior of aquatic organisms.
The Gouy phase anomaly for harmonic and time-domain paraxial Gaussian beams

SUMMARY The Gouy phase anomaly resulting from the focusing of wave solutions is illustrated using 2-D paraxial Gaussian beams. For harmonic Gaussian beams, this gives rise to a continuous variation of the Gouy phase as a function of propagation distance. This is in contrast to the discontinuous phase anomaly at caustics for ray solutions. However, as the beam-width of a Gaussian beam at a focus gets smaller, the Gouy phase anomaly becomes more concentrated near the focus and approaches that of the ray solution. The Gouy phase for a harmonic Gaussian beam is first illustrated in a homogeneous medium, and then in a quadratic velocity waveguide where the beam can pass through multiple focus points. However for multiple focus points, care must be taken to ensure that the phase remains continuous. Finally, an example is shown of the Gouy phase for a time-domain signal using a Gabor wavelet. This is validated using the finite difference method, and illustrates the progressive phase advance of a time-domain signal modifying the pulse shape with distance. Intuitively, as a wave solution gets ‘squeezed’ at a focus, it ‘squirts’ forward by slightly increasing its apparent speed in the propagation direction and modifying the pulse shape. However, this is a phase advance and not a group or energy advance and does not violate causality. Nonetheless, this could potentially influence the interpretation of travel-times using correlation techniques when using sources that generate beamed signals, for example from transducer sources in the laboratory.
TH-C-AUD C-01: Lung Mechanical Modeling Based On the 3He MR Tagging and Lobar Segmentation

Purpose: Direct measurements of the lung deformation by 3 He MR tagging during breathing motion revealed that the deformation is neither linear nor continuous. To improve the accuracy of deformable registration by finite element analysis, the lung is segmented into subanatomical regions, to allow sliding motion between lobes. Method and Materials: One healthy volunteer underwent MR tagging studies. Multiple‐slice two‐dimensional and volumetric three‐dimensional MR tagged images of the lungs were obtained at end‐inhalation and end‐exhalation, and deformation vector field (DVF) was computed. A patient CT was selected and the left lung was segmented into upper and lower lobes. The 2D contours were converted to 3D mesh and subsequently to tetrahedra for finite element analysis(FEA).Boundary conditions and material properties were assigned in the ABAQUS, FEA modeling software. Diaphragm provided the active driving pressure and the chest wall provided a passive constraint. The FEA computed DVF was compared with the measured DVF using a similarity index (SI) normalized to 1 for a perfect match and 0 for a complete mismatch. Results: A 3D lung DVF was generated from the MR tagging. Distinct discontinuity was observed between lung lobes. With the assumption that the lung is a continuous elastic object, the FEA model failed to model the discontinuity along the fissure and resulted in a low SI (0.53), which was improved to 0.89 by segmenting the lung and introducing the additional freedom of inter‐lobar motion. Conclusion: DVF measured from 3 He MR tagging can be a reference in validating deformable registration of lung, particularly in regions with low imaging contrast. Using this reference, the authors were able to significantly improve the accuracy of deformable registration with lobar segmentation in the FEA modeling.
Are 'Hot' Ears Really Hot?

Sir.—Recordings from the tympanic membrane appear superior to those obtained from most other sites commonly used for measuring body temperature.1-7Infrared determinations of temperature have been shown to be fast and accurate1,2and have been used to monitor localized increases in temperature from a variety of causes and sites.1We used a commercially available device that measures tympanic membrane temperature (FirstTEMP, Intelligent Medical Systems Inc, Carlsbad, Calif) to explore the effect of otitis media on that temperature. We assumed that patients with unilateral otitis media would display a difference in ear temperature measurements that reflected the magnitude of the local effect of the otitis, ie, that the normal ear would reflect the core temperature and the infected ear would reflect the local increase because of the infection. Patients and Methods.—Unilateral otitis media was defined as an acute illness with a normal ear opposite
Release of inorganic material during coal devolatilization

Experimental results presented in this paper indicate that coal devolatilization products convectively remove a fraction of the nonvolatile components of inorganic material atomically dispersed in the coal matrix. Results from three facilities burning six different coals illustrate this mechanism of ash transformation and release from coal particles. Titanium is chosen to illustrate this type of mass release from coal particles on the basis of its low volatility and mode of occurrence in the coal. During moderate rates of devolatilization (lo4 K/s heating rate), no significant loss of titanium is noted. At more rapid rates of heating/devolatilization (10’ K/s) a consistent but minor (3%-4%) loss of titanium is noted. During rapid devolatilization (5 X lo5 K/s and higher), significant (lo%-20%) amounts of titanium leave the coal. The loss of titanium monitored in coals ranging in rank from subbituminous to high-volatile bituminous coals and under conditions typical of pulverized-coal combustion. The amount of titanium lost during devolatilization exhibits a complex rank dependence. These results imply that other atomically dispersed material (alkali and alkaline earth elements) may undergo similar mechanisms of transformation and release. Copyright 0 1997 by The
Helicase assembly protein Gp59 of bacteriophage T4: fluorescence anisotropy and sedimentation studies of complexes formed with derivatives of Gp32, the phage ssDNA binding protein.

The gene 59 protein (gp59) of bacteriophage T4 performs a vital function in phage DNA replication by directing the assembly of gp41, the DNA helicase component of the T4 primosome, onto lagging str...
Layoffs, Equity Theory, and Work Performance: Further Evidence of the Impact of Survivor Guilt

This study explored the effects of layoffs on survivors. We assessed subjects' work performance as a function of whether a co-worker had been laid off and the circumstances of that layoff. Consiste...
Identification of Sugar Isomers by Single-Molecule Force Spectroscopy

The nanomechanical properties of β-galactan, a 1 → 4 linked β-d-galactose polysaccharide, were investigated with AFM-based single-molecule force spectroscopy. AFM captured a unique plateau at 640 pN in the force spectrogram of β-galactan, which is significantly different than the plateau at 280 pN in the force spectrogram of amylose. Thus, our results demonstrate that force spectroscopy is able to discriminate between sugar isomers in which axial and equatorial bonds at C1 and C4 are swapped.
Review: Ototoxic Characteristics of Platinum Antitumor Drugs

Cisplatin, carboplatin, nedaplatin, and oxaliplatin are widely used in contemporary oncology; however, their ototoxic and neurotoxic side effects are quite different as discussed in this review. Cisplatin is considered the most ototoxic, but despite its reputation, the magnitude of hair cell loss that occurs with a single, large drug bolus is limited and confined to the base of the cochlea. For all of these platinum compounds, a major factor limiting damage is drug uptake from stria vascularis into the cochlear fluids. Disrupting the blood-labyrinth barrier with diuretics or noise exposure enhances drug uptake and significantly increases the amount of damage. Combined treatment with ethacrynic acid (a loop diuretic) and cisplatin results in rapid apoptotic hair cell death characterized by upregulation of initiator caspase-8 and membrane death receptor, TRADD, followed by downstream executioners, caspase-3 and caspase-6. Unlike cisplatin, nedaplatin and oxaliplatin are highly neurotoxic when applied to cochlear cultures preferentially damaging auditory nerve fibers at low concentrations and hair cells at high concentrations. Carboplatin, considered far less ototoxic than cisplatin, is paradoxically highly toxic to chinchilla inner hair cells and type I spiral ganglion neurons; however, at high doses it also damages outer hair cells. Hair cell death from cisplatin and carboplatin is characterized in its early stages by upregulation of p53; blocking p53 expression with pifithrin-α prevents hair cell death. Major differences in the toxicity of these four platinum compounds may arise from several different metal transporters that selectively regulate the influx, efflux, and sequestration of these drugs.
Vowel shapes: an open-source, interactive tool to assist singers with learning vowels

The mastery of vowel production is central to developing vocal technique and may be influenced by language, musical context or a coach's direction. Currently, students learn through verbal descriptions, demonstration of correct vowel sounds, and customized exercises. Vowel Shapes is an interactive practice tool that automatically captures and visualizes vowel sounds in real time to assist singers in correctly producing target vowels. The system may be used during a lesson or as a practice tool when an instructor is not present. Our system's design was informed by iterative evaluations with 14 students and their vocal professor from the Eastman School of Music, University of Rochester. Results from an exploratory evaluation of the system with 10 students indicated that 70% of the participants improved their time to reach an instructor-defined target. 90% of the students in the evaluation would use this system during practice sessions.
Enterically Transmitted Non-A, Non-B Hepatitis: Identification of Virus-Associated Antigen in Experimentally Infected Cynomolgus Macaques

An antigen (HEVAg) associated with enterically transmitted non-A, non-B (ET-NANB) hepatitis virus has been identified in hepatocytes of cynomolgus macaques (Macaca fascicularis) infected with ET-NANB hepatitis by using an immunofluorescent probe prepared from serum previously shown by immune electron microscopy to react with ET-NANB viruslike particles. HEVAg was observed in the cytoplasm of hepatocytes in 27 of 29 infected macaques in five passages of the diseases but not in uninoculated macaques or chimpanzees with various types of experimentally induced viral hepatitis. Specificity of the assay was confirmed by blocking tests using preinoculation, acute, and convalescent sera from ET-NANB hepatitis patients and from experimentally infected macaques. Concordant results of fluorescent antibody blocking and immune electron microscopy assays suggest that hepatocellular HEVAg is associated with 32- to 34-nm viruslike particles etiologically linked to disease. Antibodies to HEVAg were identified, and the titers were determined by using a fluorescent antibody blocking assay on liver tissue sections from macaques infected with ET-NANB hepatitis.
Covariance Structure Model Fit Testing under Missing Data: An Application of the Supplemented EM Algorithm.

We apply the Supplemented EM algorithm ( Meng & Rubin, 1991 ) to address a chronic problem with the "two-stage" fitting of covariance structure models in the presence of ignorable missing data: the lack of an asymptotically chi-square distributed goodness-of-fit statistic. We show that the Supplemented EM algorithm provides a convenient computational procedure that leads to such a chi-square statistic, and we provide a SAS macro implementing this method. Our derivations are corroborated with results from a small simulation study. We also apply the proposed method to 2 empirical data sets: (a) confirmatory factor analysis of Mardia, Kent, & Bibby's 1979 Open-book Closed-book data and (b) conditional latent curve modeling of adolescent aggressive behavior as discussed by Curran (1997) .
Basic considerations for DC to DC conversion networks

For a number of basic reasons, a dc to dc conversion network is defined as an electrical or electromechanical network in which the sole source of energy is a dc source and which is capable of supplying direct current to a load at a voltage level or at a current level which exceeds that of the source. Several constraints encountered in all dc to dc conversion networks are pointed out including the necessity for dc to ac inversion as an intermediate step within a dc to dc conversion network, the minimum amount of ac power which must be involved in this intermediate step, and the requirement for any network in which dc to ac inversion takes place to contain one or more active resistors which are properly connected in relation to the dc source. The relationship which exists between the characteristics of an active resistor and the maximum ac power which the active element can cause to be generated within any network is defined quantitatively and discussed in some detail. Heuristic in nature, the paper points out and discusses certain basic impossibilities, although its primary purpose is to be provocative and to provide useful guidelines and ideas for further basic research in the power-conditioning field.
A note on Lagrange multipliers with several binding constraints

Abstract When a function is optimized subject to one constraint, the Lagrange multipliers for the primal and dual problems are reciprocals. Here, I show how this result generalizes to the case where a function is optimized subject to several binding constraints.
T for two: when helpers need help.

Abstract This article discusses forms of cell cooperation involving CD4 T cells and their impact on adaptive immunity. In particular, evidence will be presented in favor of cooperation among CD4 T cells of different specificity, its molecular basis and functional significance. Th–Th cooperation, or help for helpers, will be discussed in relation to the induction of anti-tumor responses and, in converse, the generation of autoimmunity. A model is proposed where Th–Th cooperation may represent the structure/function substrate for the control of self/non-self discrimination and peripheral tolerance in vivo.
Immunologic memory in cutaneous leishmaniasis.

Summary Leishmania major infections induce solid immunity to reinfection. Experimental studies in mice indicate that the CD4+ T cells responsible for this immunity include two populations: parasite-dependent T effector cells and parasite-independent central memory T (Tcm) cells. While there currently is no vaccine for leishmaniasis, the existence of a long-lived population of Tcm cells that does not require the continued presence of live parasites suggests that a vaccine that expands these cells might be efficacious.
Consequences of cAMP-binding site mutations on the structural stability of the type I regulatory subunit of cAMP-dependent protein kinase.

The regulatory (R) subunit of cAMP-dependent protein kinase (cAPK) is a multidomain protein with two tandem cAMP-binding domains, A and B. The importance of cAMP binding on the stability of the R subunit was probed by intrinsic fluorescence and circular dichroism (CD) in the presence and absence of urea. Several mutants were characterized. The site-specific mutants R(R209K) and R(R333K) had defects in cAMP-binding sites A and B, respectively. R(M329W) had an additional tryptophan in domain B. Δ(260−379)R lacked Trp260 and domain B. The most destabilizing mutation was R209K. Both CD and fluorescence experiments carried out in the presence of urea showed a decrease in cooperativity of the unfolding, which also occurred at lower urea concentrations. Unlike native R, R(R209K) was not stabilized by excess cAMP. Additionally, CD revealed significant alterations in the secondary structure of the R209K mutant. Therefore, Arg209 is important not only as a contact site for cAMP binding but also for the intrinsic st...
Controlled dielectrophoretic assembly of multiwalled carbon nanotubes

The authors report on a real-time control method for assembly of a single or small number of multiwalled carbon nanotubes (MWNTs) onto microelectrodes by dielectrophoresis (DEP). On the basis of an impedance model and a real-time gap impedance monitoring method to evaluate and identify the number of MWNTs spanning an electrode gap, it has been demonstrated that a real-time gap impedance signal can be used to control the DEP process of MWNTs. The goal is controlled assembly with a connecting resistance of less than a defined limit or with a defined number of MWNT connections. With a control strategy designed for the DEP assembly of a small number of MWNTs, predefined numbers of connections from 1−3 have been achieved across an electrode gap.
Interference Effects of Pseudo-Random Frequency-Hopping Signals

When a pseudo-random frequency-hopping signal is intercepted by a conventional receiver operating within the same frequency band, the interfering signal has the form of a pulse-amplitude modulated signal. Each pulse amplitude is dependent upon the hopping frequency and the selectivity characteristic of the victim receiver. The probability density function for the interfering pulse amplitude prior to demodulation is determined when the probability density function for the hopping frequency is uniform and the victim-receiver characteristic is 1) ideal flat bandpass, 2) single tuned, and 3) Gaussian shaped. It is shown that the average interfering pulse amplitude and interference power decrease as the frequency-hopping bandwidth increases with respect to the victim-receiver bandwidth. Fast Fourier transform computer techniques are used to obtain the probability density function of the interference amplitude in a Gaussian receiver when several (from 2 to 10) pseudo-random frequency-hopping systems are simultaneously using the same frequency band. The probability that the interference exceeds a prescribed threshold value is computed from the derived probability density functions. This probability may be used in signal-to-interference ratio calculations, to describe the capture effect, or to compute the expected number of clicks produced in an FM discriminator.