cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of Ice Slurry Ingestion on Cardiovascular Drift and V˙O2max during Heat Stress.

External body cooling by fan airflow mitigates the decrease in maximal oxygen uptake (V˙O2max) associated with cardiovascular (CV) drift during cycling in hot conditions. It remains unknown whether internal body cooling via ice slurry ingestion elicits a similar response. Purpose This study aimed to test the hypothesis that ice slurry ingestion attenuates the magnitude of CV drift and accompanying decrement in V˙O2max during heat stress. Methods Eight men completed a graded exercise test on a cycle ergometer in 22°C to measure V˙O2max. Then on three separate occasions (in randomly assigned counterbalanced treatment orders), they cycled at 60% V˙O2max in hot conditions (35°C, 40% RH) for 15 min, 45 min with tepid (23°C) fluid ingestion (45FL), or 45 min with ice (-1°C) slurry ingestion (45ICE), followed immediately by measurement of V˙O2max. The purpose of the separate 15- and 45-min trials was to measure CV drift and V˙O2max over the same time interval. Results The increase in heart rate between 15 and 45 min was twice as large in 45FL (8.6%) compared with 45ICE (4.6%; P = 0.02). Stroke volume declined by 6.2% in 45FL but was maintained with 45ICE (P = 0.02). V˙O2peak decreased from 15 to 45 min by 8.6% and 9.0% in 45FL and 45ICE, respectively, but was not different between conditions (P = 0.79). Conclusion Although ice slurry ingestion attenuated CV drift more than fluid ingestion, it did not mitigate the decline in V˙O2max. Contrary to previous findings, when ice slurry is ingested, changes in heart rate may not reflect changes in relative metabolic intensity during prolonged exercise in the heat.
Phase distribution control of a population of oscillators

Abstract The collective behavior of biological oscillators has been recognized as an important problem for several decades, but its control has come into limelight only recently. Much of the focus for control has been on desynchronization of an oscillator population, motivated by the pathological neural synchrony present in essential and parkinsonian tremor. Other applications, such as the beating of the heart and insulin secretion, require synchronization, and recently there has been interest in forming clusters within an oscillator population as well. In this article, we use a formulation that allows us to devise control frameworks to achieve all of these distinct collective behaviors observed in biological oscillators. This is based on the Fourier decomposition of the partial differential equation governing the evolution of the phase distribution of a population of identical, uncoupled oscillators. Our first two control algorithms are Lyapunov-based, which work by decreasing a positive definite Lyapunov function towards zero. Our third control is an optimal control algorithm, which minimizes the control energy consumption while achieving the desired collective behavior of an oscillator population. Motivated by pathological neural synchrony, we apply our control to desynchronize an initially synchronized neural population. Given the proposed importance of enhancing spike time dependent plasticity to stabilize neural clusters and counteract pathological neural synchronization, we formulate the phase difference distribution in terms of the phase distribution, and prove some of its fundamental properties, and in turn apply our control to transform the neural phase distribution to form clusters. Finally, motivated by eliminating cardiac alternans, we apply our control to phase shift a synchronous cardiac pacemaker cell population. For the systems considered in this paper, the control algorithms can be applied to achieve any desired traveling-wave phase distribution, as long as the combination of the initial phase distribution and phase response curve is non-degenerate. To demonstrate the effectiveness of our control for each of these applications, we show that a population of 100 phase oscillators with the applied control mimics the desired phase distribution.
Financial Market as Driver for Disparity in Wealth Accumulation—A Receding Horizon Approach

In this paper we study the extent to which the financial market has contributed to wealth disparities. To that end we introduce a stochastic dynamic model of wealth accumulation with preferences, consumption and portfolio choice, which roughly replicates the long-term evolution of assets under management. Using a receding horizon approach for solving nonlinear model predictive control (NMPC) in finite time, we run simulations with three types of investors (conservative, moderate and aggressive) corresponding, roughly, to the social population segments identified in Piketty (Le capital au XXIe siecle, Seuil, Paris, 2013) for thinking about distributional matters, namely the lower segment (bottom 50%), the middle segment (middle 40%), and the upper segment (upper 10%) respectively. We estimate the impact on the end wealth distribution of first, investor-level characteristics (calibrated for each investor class), which directly impact the saving rate; and second, higher expected returns for wealthier (aggressive) investors in the top decile through the availability of leverage. We find that differences in investor-level characteristics (and significantly the length of the receding horizon) combined with access to leverage are sufficient to generate fat tails. Though results are obtained in a stochastic approach, the outcomes are less related to stochastic shocks than to some feedback and scale effects operating in favor of some investors in the financial market.
Fuzzy Mathematical Programming Approaches to Design Cell Formation in Cellular Manufacturing Systems

Mathematical programming approaches based on fuzzy set theory are proposed for cell formation design in cellular manufacturing systems (CMS). The objective is to find part families and machine groups to minimize the fuzzy total production cost consisting of processing and maintenance costs subject to fuzzy machine time availability. Two cases are used to illustrate the applications. Results indicate that the cell formations obtained by the fuzzy approaches yield less total production costs compared to the non-fuzzy (crisp) approaches.
Gold(I) Cationization Promotes Ring Opening in Lysine-Containing Cyclic Peptides.

A strategy to sequence lysine-containing cyclic peptides by MSn is presented. Doubly protonated cyclic peptides ions are transformed into gold (I) cationized peptide ions via cation switching ion/ion reaction. Gold(I) cationization facilitates the oxidation of neutral lysine residues in the gas phase, weakening the adjacent amide bond. Upon activation, facile cleavage N-terminal to the oxidized lysine residue provides a site-specific ring opening pathway that converts cyclic peptides into acyclic analogs. The ensuing ion contains a cyclic imine as the new N-terminus and an oxazolone, or structural equivalent, as the new C-terminus. Product ions are formed from subsequent fragmentation events of the linearized peptide ion. Such an approach simplifies MS/MS data interpretation as a series of fragment ions with common N- and C-termini are generated. Results are presented for two cyclic peptides, sunflower trypsin inhibitor and the model cyclic peptide, β-Loop. The power of this strategy lies in the ability to generate the oxidized peptide, which is easily identified via the loss of HAuNH3 from [M + Au]+. While some competitive processes are observed, the site of ring opening can be pinpointed to the lysine residue upon MS4 enabling the unambiguous sequencing of cyclic peptides.
Targeting NRF2 for the Treatment of Friedreich's Ataxia: A Comparison among Drugs.

NRF2 (Nuclear factor Erythroid 2-related Factor 2) signaling is impaired in Friedreich’s Ataxia (FRDA), an autosomal recessive disease characterized by progressive nervous system damage and degeneration of nerve fibers in the spinal cord and peripheral nerves. The loss of frataxin in patients results in iron sulfur cluster deficiency and iron accumulation in the mitochondria, making FRDA a fatal and debilitating condition. There are no currently approved therapies for the treatment of FRDA and molecules able to activate NRF2 have the potential to induce clinical benefits in patients. In this study, we compared the efficacy of six redox-active drugs, some already adopted in clinical trials, targeting NRF2 activation and frataxin expression in fibroblasts obtained from skin biopsies of FRDA patients. All of these drugs consistently increased NRF2 expression, but differential profiles of NRF2 downstream genes were activated. The Sulforaphane and N-acetylcysteine were particularly effective on genes involved in preventing inflammation and maintaining glutathione homeostasis, the dimethyl fumarate, omaxevolone, and EPI-743 in counteracting toxic products accumulation, the idebenone in mitochondrial protection. This study may contribute to develop synergic therapies, based on a combination of treatment molecules.
Hepatic alterations during the development and progression of cancer cachexia

Cancer-associated bodyweight loss (cachexia) is a hallmark of many cancers and is associated with decreased quality of life and increased mortality. Hepatic function can dramatically influence whol...
Transcriptional Programming of Human Mechanosensory Neuron Subtypes from Pluripotent Stem Cells

Summary Efficient and homogeneous in vitro generation of peripheral sensory neurons may provide a framework for novel drug screening platforms and disease models of touch and pain. We discover that, by overexpressing NGN2 and BRN3A, human pluripotent stem cells can be transcriptionally programmed to differentiate into a surprisingly uniform culture of cold- and mechano-sensing neurons. Although such a neuronal subtype is not found in mice, we identify molecular evidence for its existence in human sensory ganglia. Combining NGN2 and BRN3A programming with neural crest patterning, we produce two additional populations of sensory neurons, including a specialized touch receptor neuron subtype. Finally, we apply this system to model a rare inherited sensory disorder of touch and proprioception caused by inactivating mutations in PIEZO2. Together, these findings establish an approach to specify distinct sensory neuron subtypes in vitro, underscoring the utility of stem cell technology to capture human-specific features of physiology and disease.
TIMs, TAMs, and PS- antibody targeting: implications for cancer immunotherapy.

Immunotherapy for cancer is making impressive strides at improving survival of a subset of cancer patients. To increase the breadth of patients that benefit from immunotherapy, new strategies that combat the immunosuppressive microenvironment of tumors are needed. Phosphatidylserine (PS) signaling is exploited by tumors to enhance tumor immune evasion and thus strategies to inhibit PS-mediated immune suppression have potential to increase the efficacy of immunotherapy. PS is a membrane lipid that flips to the outer surface of the cell membrane during apoptosis and/or cell stress. Externalized PS can drive efferocytosis or engage PS receptors (PSRs) to promote local immune suppression. In the tumor microenvironment (TME) PS-mediated immune suppression is often termed apoptotic mimicry. Monoclonal antibodies (mAbs) targeting PS or PSRs have been developed and are in preclinical and clinical testing. The TIM (T-cell/transmembrane, immunoglobulin, and mucin) and TAM (Tyro3, AXL, and MerTK) family of receptors are PSRs that have been shown to drive PS-mediated immune suppression in tumors. This review will highlight the development of mAbs targeting PS, TIM-3 and the TAM receptors.
Process Dependent Switching Dynamics of Ferroelectric Hafnium Zirconate

The CMOS-compatible ferroelectrics (FE) based on HfO 2 are being widely explored for emerging memory, logic, and neuromorphic devices [1]. While the applications hinge on the dynamic switching of the FE, process optimization often relies on information obtained from measurement of the quasi-static polarization-field (P-E) hysteresis loops [2]. We have recently been refining methods for characterizing the polarization reversal dynamics of polycrystalline FEs, such as Hafnium Zirconate (HZO). Because of the close agreement between the nucleation limited switching (NLS) model and measurements, detailed physical information such as minimum switching time and activation field distributions can be extracted from polarization reversal measurements vs. pulse amplitude and duration [3]. This characterization has been successfully applied to the prediction of FE switching dynamics under arbitrary voltage waveforms [4]. Here, we utilize this method to study the dependence of the switching dynamics of FE HZO formed by atomic layer deposition (ALD) vs. electrode metal and post deposition anneal temperature.
India–Bangladesh Border Dispute: History and Post-LBA Dynamics: by A. Ranjan, Singapore, Springer, 2018, 159 pp., $ 54.99, eBook ISBN 978-981-10-8384-6

Identity, emotion, and border: it is around these three words that Amit Ranjan pivots his thesis for analyzing border disputes between India and Bangladesh in his book, India–Bangladesh Border Disp...
COVID-19 as a Force Majeure in Corporate Transactions

This paper surveys the use of pandemic-related provisions in Material Adverse Effects ("MAE") provisions in a large data set of publicly disclosed MA but when an RTF is present, its magnitude tends to be smaller in the absence of any pandemic-specific carve-out, suggesting some degree of observational complementarity between these terms.
2-D Circuit-Based Bianisotropic Omega Media

In one dimension, a circuit network representation has been established for bianisotropic materials with an omega response (omega media). However, 2-D circuit-based or transmission-line metamaterials have been restricted to those with only magnetic and electric responses. This article proposes a 2-D circuit-based metamaterial that is equivalent to an omega medium. A lumped element unit cell composed of asymmetric $\pi $ -networks is proposed and validated using a circuit simulator. Circuit analysis of the metamaterial is performed using transmission (ABCD) matrices. A medium equivalency is then established in the homogeneous limit. The application of a 2-D omega medium as an impedance matching layer with phase and power flow control is explored, and a design procedure is developed. The impedance matching layer is then implemented using the proposed lumped element unit cell, and its performance is confirmed using Keysight’s Advanced Design System (ADS).
Cannabis Extract Composition Determines Reinforcement in a Vapor Self-Administration Paradigm.

The legalization of cannabis and shifting cultural attitudes have driven an increase in cannabis use and the proliferation of vapor delivery devices. The DSM-V recognizes “cannabis use disorder” under the umbrella of substance use disorders, but its neural mechanisms require greater clarity ([
Dem Bewusstsein auf der Spur

Krempeln wir nun die Armel hoch und machen wir uns daran, die Teile des Gehirns zu identifizieren, die am engsten mit dem Bewusstsein verbunden sind. Wie sich zeigt, konnen etliche Regionen des Zentralnervensystems durchaus ohne Erleben auskommen. Die bioelektrische Aktivitat von Millionen von Neuronen in wenig zutraglicher Neuro-Nachbarschaft tragt rein gar nichts zum bewussten Empfinden bei, wahrend andere Regionen privilegierter sind. Worin besteht der Unterschied?
Do Foreign Investors Care about Labor Market Regulations

The authors take a new look at the regulatory determinants of foreign direct investment (FDI) by asking whether labor market flexibility affects FDI flows across 25 Western and Eastern European countries. Their analysis is based on firm level data on new investments during the 1999-2001 period. The authors employ a variety of labor market flexibility measures that capture different aspects of labor laws along with a comprehensive set of controls for business climate characteristics. Indices of labor market regulations reflect the flexibility of individual and collective dismissals, the length of the notice period, and the required severance payment. The results suggest that greater flexibility in the host country's labor market relative to that in the investor's home country is associated with larger FDI inflows, and this effect is found to be stronger in the case of transition economies. The findings indicate that as the labor market flexibility in the host country increases from inflexible (for example, Slovakia) to flexible (for example, Hungary), the volume of investment increases by between 14 and 18 percent. FDI in service sectors appears to be more affected than investments in manufacturing.
Forced vibrations of size-dependent rods subjected to: impulse, step, and ramp excitations

Forced longitudinal vibration response of nonlocal strain gradient (NLSG) rods is scrutinized and compared with nonlocal (NL), strain gradient (SG), and classical (CL) rods. In this respect, size-dependent kinematics and extended Hamilton’s principle are utilized to derive governing equations of motion. For the first time, forced longitudinal vibratory behavior of non-classical and classical rods is presented including three different types of non-harmonic forcing functions: unit impulse, unit step, and unit ramp. Forcing terms are functions of both temporal and spatial domains. Nonlocal strain gradient and nonlocal rod models take into account the Laplacian of the external forcing term as well. This implies that in models including nonlocal effects (NL, NLSG-h, s, n), forcing term is reduced by the order of its Laplacian with respect to spatial variables. Effect of non-classical parameters over time-domain response of the system is analyzed in details. Results are compared with benchmark for the sake of evaluation. This implies the necessity of adopting proper values of non-classical theory and corresponding parameters through analysis of forced oscillations of small-scaled size-dependent rods. Such external excitations are modeled using spatial Dirac delta function as a concentrated force applying at the critical point of mode shape function. Findings of this research reveal the underlying impact of non-classical theorems along with corresponding non-classical parameters over the prediction of the response of size-dependent rod elements for wide range of applications such as in musical instruments, navigating equipment, gyroscopes, control of robotics, sensors and actuators, resonators, energy harvesters, and vibration control systems.
Manipulating microcompartment operons to study mechanism and function.

Abstract The gene systems that encode functional bacterial microcompartments (BMCs) are typically comprised of between 10–23 genes, often in a contiguous operon. BMC genes can be studied as whole native operons or as subsets of genes that form structures for specific applications. Recent examples of such studies highlight the flexible modular nature of BMC operons/genes and the options that exist to harness their functions via manipulation at the DNA level. This work also demonstrates the transfer and functional expression of BMC operons/genes across bacterial species. Recombineering, DNA synthesis technology, and advanced cloning techniques have all been applied in creative ways to study the nature of BMC mechanism and function.
Development of Mathematical Practices Through Word Problem–Solving Instruction for Students With Autism Spectrum Disorder:

The Common Core State Standards for Mathematics highlight the importance of not only content standards for mathematics but also mathematical practices such as communication, representation, and rea...
Experimental Investigation of Time-Dependent Deformation in Brittle Marcellus Shale

Coal mining activity disturbs the natural equilibrium of in situ stress state such that the induced stresses deform the surrounding rock mass. Although the installation of roof supports typically prevents rock deformation, rock mass failure may still occur in bolted roof. The erratic failure of rock mass after few days to months and years of excavation is the result of time-dependent deformation of roof rock under constant surrounding stresses. In the current research, the triaxial laboratory creep experiments proved that Marcellus shale exhibits time-dependent deformation under constant stress that was smaller than the failure strength. However, unlike conventional experimental results, the time-dependent deformation did not depend on the level of constant stress. The often-neglected initial state of specimens and intrinsic heterogeneity highly influenced the time-dependent failure of Marcellus shale.
Effect of storage relative humidity on the survival kinetics of salmonella spp., in different tree nut flours

Abstract This study determined the effect of relative humidity (RH) on the survival kinetics of Salmonella enterica in tree nut flours during long term storage. Three types of tree nut (almond, chestnut, and hazelnut) flours were seed inoculated with Salmonella (3-strain) to achieve about 8 log CFU/g and stored at different RH (25, 45 and 70%) conditions under ambient temperature (21 ± 2 °C) storage for up to 120 days. Samples were analyzed at regular intervals (0, 7, 14, 21, 30, 60, 90, and 120 days) to determine the survivors on both selective and non-selective media. Salmonella populations were declined by 2.28–4.68 log CFU/g on the tested flours during the storage period. Compared to RH 25%, 70% showed a significant (P ≤ 0.05) decrease in Salmonella survival. Type of flour was found to have a variable effect on the survival of Salmonella. After 120 days of storage at 70% RH, reductions were higher on hazelnut followed by almond and chestnut flours, respectively. Bacterial population decline was found to be higher during the first 60 days of storage at 25 and 45% RH. At the same time, cell viability decreased most between 60 and 120 d in hazelnut and almond flour at 70% RH.
Anesthesia for Long QT Syndrome

This review article seeks to discuss the salient information about the known genetic variants associated with congenital long QT syndrome (LQTS) and describe the current anesthetic considerations. LQTS describes a heterogeneous group of patients with varying genetic mutations that cause an increased risk of torsade de pointe and sudden death. Research continues to identify more genetic mutations associated with LQTS subtypes. Publications of clinical experience with LQTS patients under general anesthesia provide new insights on the risk of medication inducing arrhythmias in these patients. Many medications used during general anesthesia are known to prolong the QTc interval. Patients with LQTS are at increased risk of arrhythmias under general anesthesia.
Reelin, GABA, FMRP, and Autism

Autism is a heterogeneous neurodevelopmental disorder. The etiology of autism remains unknown although both genetic and environmental factors are likely to be involved. These factors disrupt the course of normal brain development from the cellular to the gross anatomical levels. The Reelin, gamma-aminobutyric acid (GABA), and fragile X mental retardation protein (FMRP)—metabotropic glutamate receptor 5 (mGluR5) signaling systems play important roles during the development of the nervous system. Disruption of these pathways is likely to lead to altered synaptic transmission and, ultimately, the cognitive and behavioral deficits associated with autism. This chapter describes each of these signaling systems and summarizes the current evidence that link them to autism. Therapies that target molecules in these signaling systems may provide new means of treating the core symptoms of autism.
AN OVERVIEW OF PERFORMANCE MEASURES FOR HEAVY COMMERCIAL VEHICLES IN NORTH AMERICA.

In recent studies, it has become apparent that a set of safety–related performance measures for heavy vehicles can be useful in the design process as well as in the more conventional realm of screening heavy vehicles by regulation. In Canada, these regulations control, separately, the combined trailer length and overall vehicle length, total vehicle weight, maximum axle–load, multiple–axle group spacing, and the characteristics of a few selected components of new vehicles (e.g. service and emergency air and/or hydraulic brake systems). None of the existing regulations has been applied for quantifying the dynamic properties of individual vehicles, either newly designed or already in service; instead they have been used to qualify classes or groupings of vehicles. The objective of this paper is to present an overview of the efforts made in North America to develop a set of safety–related performance measures and promote their use for determining and controlling the dynamic quality of heavy vehicles on an individual basis from both the design and regulatory standpoints.
Industrial buyer behavior at trade shows

Abstract Although trade shows are a major marketing tool, little research has examined how to capitalize on the medium's sales potential. This article analyzes the buying behavior of trade show attendees in order to devise an approach to selling that is best adapted to the unique show environment. The industrial buying literature is used to frame hypotheses which test aspects of attendee behavior that underlie and motivate effective selling strategies for trade shows.
Photosynthesis in Rhodospirillum rubrum. IV. Isolation and characterization of ribulose 1,5-diphosphate carboxylase.

Abstract Ribulose 1,5-diphosphate carboxylase has been isolated from autotrophically cultured Rhodospirillum rubrum. The molecular weight is 120,000. The Km for ribulose 1,5-diphosphate is 83 mm, and for CO2 is 59 mm. The enzyme is inhibited by three important metabolites: citrate, an intermediate of the tricarboxylic acid cycle; inorganic phosphate; and 3-phosphoglyceric acid, the product of the reaction catalyzed by the carboxylase. Both the levels and the activity of ribulose 1,5-diphosphate carboxylase are apparently subject to metabolic control in this facultative photoautotroph.
The rebuilding generation

Dr. Joseph Caytak is a busy man. When he returned to his office after being away for several days observing Rosh Hashanah, he was greeted by a foot-high stack of files and messages. And life is almost as hectic at home following the birth of his 11th child. “We love children,” he explains. “
IMPURITY-DRIVEN RIPPLING MODES IN TOKAMAKS

ABSTRACT Rippling modes arising from nonuniformities in Z eff in an impure tokamak plasma are analyzed: instabilities are found even in the case of large electron thermal conduction along field lines. For typical parameters, modes up to high m-values are unstable. The resulting magnetic perturbations, although small, could provide a mechanism for significant anomalous cross-field thermal transport.
Cost-effectiveness of lower extremity compression ultrasound in emergency department patients with a high risk of hemodynamically stable pulmonary embolism

ACADEMIC EMERGENCY MEDICINE 2011; 18:22–31 © 2011 by the Society for Academic Emergency Medicine Abstract Background: Computed tomography angiograms (CTAs) for patients with suspected pulmonary embolism (PE) are being ordered with increasing frequency from the emergency department (ED). Strategies are needed to safely decrease the utilization of CTs to control rising health care costs and minimize the associated risks of anaphylaxis, contrast-induced nephropathy, and radiation-induced carcinogenesis. The use of compression ultrasonography (US) to identify deep vein thromboses (DVTs) in hemodynamically stable patients with signs and symptoms suggestive of PE is highly specific for the diagnosis of PE and may represent a cost-effective alternative to CT imaging. Objectives: The objective was to analyze the cost-effectiveness of a selective CT strategy incorporating the use of compression US to diagnose and treat DVT in patients with a high pretest probability of PE. Methods: The authors constructed a decision analytic model to evaluate the scenario of an otherwise healthy 59-year-old female in whom PE was being considered as a diagnosis. Two strategies were used. The selective CT strategy began with a screening compression US. Negative studies were followed up with a CTA, while patients with positive studies identifying a DVT were treated as though they had a PE and were anticoagulated. The universal CT strategy used CTA as the initial test, and anticoagulation was based on the CT result. Costs were estimated from the 2009 Medicare data for hospital reimbursement, and professional fees were obtained from the 2009 National Physician Fee Schedule. Clinical probabilities were obtained from existing published data, and sensitivity analyses were performed across plausible ranges for all clinical variables. Results: In the base case, the selective CT strategy cost $1,457.70 less than the universal CT strategy and resulted in a gain of 0.0213 quality-adjusted life-years (QALYs). Sensitivity analyses confirm that the selective CT strategy is dominant above both a pretest probability for PE of 8.3% and a compression US specificity of 87.4%. Conclusions: A selective CT strategy using compression US is cost-effective for patients provided they have a high pretest probability of PE. This may reduce the need for, and decrease the adverse events associated with, CTAs.
The Bargain Value Model and a Comparison of Managerial Implications with the Linear Learning Model

A new stochastic brand choice model, the Bargain Value Model, is introduced. Using consumer panel data, the model predicts an individual household's probability of purchasing various brands as a function of the prevailing price of those brands. Based on consumer behavior constructs, the model differs sharply from the Linear Learning Model in its behavioral interpretation. This difference leads the models to have divergent managerial policy implications. After describing the Bargain Value Model, the differences between the models are explored along with some empirical results.
SU-E-T-553: Dose-Mass Vs. Dose-Volume Optimization: A Phantom Study.

Purpose: To demonstrate the merits of mass‐based optimization in comparison with volume‐based optimization using a simple test phantom. Methods: Dose‐volume‐histogram‐based (DVH‐based) quadratic objective functions are converted into dose‐mass‐histogram‐based (DMH‐based) objective functions by multiplying per‐voxel volumes by per‐voxel densities within the objective. A digital phantom with a 1.0 g/cm3 target is constructed for irradiation with two beams: one beam path contains a 0.2 g/cm3 volume‐of‐interest (VOI0.2) while the orthogonal beam‐path contains an equal‐volume 0.8 g/cm3 VOI (VOI0.8). Monitor‐units are computed to achieve a 100 cGy average target dose for each individual beam, and for two‐beam DVH‐based and DMH‐based optimizations.Results: For single‐beam irradiation through VOI0.2, the average dose to VOI0.2 is 20.5 cGy. For single‐beam irradiation through VOI0.8, the average dose to VOI0.8 is 25.2 cGy. Traversing the low density volume results in ∼23% lower dose. When DVH‐ and DMH‐based optimizations are performed such that target dose‐volume‐histograms of the optimizations match, for the DVH optimization 60% vs. 40% of the dose is delivered through VOI0.2 vs. VOI0.8. For DMH‐optimization, the split between dose delivered through VOI0.2 vs. VOI0.8 is 70% vs. 30%. Conclusions: When density is constant, there is no difference between DVH‐ and DMH‐based optimizations. However, in heterogeneous media, DMH and DVH solutions differ when low and high density materials have the same dose objectives. Delivering target dose through lower density VOIs facilitates target dose deposition due to a decrease in attenuating material, and the decreased attenuation lowers dose to the low density VOI. From mathematical and physical points of view dose‐mass optimization is more general than dose‐volume optimization.
The H+ ATPase regulatory subunit of Methanococcus thermolithotrophicus: amplification of an 800 bp fragment by polymerase chain reaction.

Abstract An 800 bp fragment of Methanococcus thermolithotrophicus genomic DNA was amplified by the polymerase chain reaction method using primers designed from conserved regions of the V-type H + ATPase regulatory subunits from the archaebacterium Sulfolobus , and several eukaryotes. Although more than one product was obtained, only one of them had the expected size and was exclusively amplified in the presence of the left and right primers. The DNA and the deduced protein sequences of the putative Methanococcus H + ATPase subunit revealed homology to the corresponding sequences in Sulfolobus and eukaryotes (about 60% identical residues) and a less evident homology to the eubacterial F 1 -ATPase α-subunit (22% identical residues with E. coli ).
Superconductivity in 3d series amorphous transition metal alloys

Abstract The superconducting transition temperature, upper critical field, electrical conductivity and Hall coefficient have been measured in situ for a series of TiV, VCr and TiCr thin alloy films which have been quench condensed on substrates held at liquid helium temperature in an ultrahigh vacuum codeposition chamber. Addition of chromium strongly suppresses the superconducting transition temperature of these alloys. There appears to be an initial increase in the density of states at the Fermi energy with the addition of chromium as determined from the resistivity and critical field slope. Further addition of chromium appears to decrease the density of states. The Hall coefficient for these alloys, like those of other early transition metal amorphous alloy films, is positive.
Aortic Medial Elastic Fiber Loss in Acute Ascending Aortic Dissection

The cause of acute aortic dissection continues to be debated. One school of thought suggests that underlying aortic medial cystic necrosis is the common denominator. The purpose of the present study was to determine if there was loss and, if so, how much loss of medial elastic fibers in the ascending aorta in patients with acute aortic dissection with the entrance tear in the ascending aorta. We examined operatively excised ascending aortas in 69 patients having acute dissection with tears in the ascending aorta. Patients with previous aortotomy, healed dissection, and connective tissue disorders were excluded. The 69 patients' ages ranged from 31 to 88 years (mean 56); 49 were men and 20 were women. Loss of aortic medial elastic fibers was graded as 0 (no loss), 1+ (trace), 2+ (mild), 3+ (moderate), and 4+ (full thickness loss). Of these 69 patients, 56 (82%) had 0 or 1+ elastic fiber loss; 13 patients (18%), 2+ to 4+ loss including 4 with 2+, 6 with 3+, and 2 with 4+. Nearly all patients (97%) had a history of systemic hypertension and/or had received antihypertensive drug therapy. In conclusion, most patients (82% in this study) having acute aortic dissection with entrance tears in the ascending aorta have normal numbers or only trace loss of aortic medial elastic fibers. Thus, underlying abnormal ascending aortic structure uncommonly precedes acute dissection.
Treatment of Chronic Bullous Disease of Childhood

Chronic bullous disease of childhood (CBDC) is generally a self-limited disease of prepubescent children that resolves within months to years. However, as discussed in the previous issue of Dermatologic Clinics, the disease is associated with significant morbidity and usually requires systemic therapy. Treatment is aimed at controlling blistering while avoiding adverse reactions. There are several anecdotal reports of treatment options, but controlled or comparative studies are lacking. This article discusses the management options of CBDC in more detail.
On the Nature of Electronic Transitions in Radicals: An Extended Single Excitation Configuration Interaction Method

We propose that the generalization of pure spin single reference excited state theories from molecules with closed shell ground states to radicals be based on a redefinition of the meaning of excitation levels. Open shell single substitutions are expanded to include spin-adapted double excitations which traverse the singly occupied orbitals. These excitations are deleted from the expanded open shell double substitutions, which include the corresponding spin-adapted triple substitutions (e.g., a pair of the excitations traverses the singly occupied orbitals), etc. Applied to single excitation configuration interaction (CIS), this approach defines a spin-adapted extended CIS (XCIS) theory for the excited states of radicals. XCIS is size consistent and variational and has computational complexity that scales in the same way as CIS with molecular size. More low-lying excited states of radicals are correctly described by XCIS than by the restricted open shell CIS method. This is demonstrated by calculations on...
Chiral synthesis via organoboranes. 38. Selective reductions. 48. Asymmetric reduction of trifluoromethyl ketones by B-chlorodiisopinocampheylborane in high enantiomeric purity

(−)-B-Chlorodiisopinocampheylborane [(−)-DIP-ChlorideTM, 1], introduced by us several years ago, has been shown to reduce prochiral aryl and alkyl perfluorinated ketones to the corresponding optically active alcohols in very high ee. For example, 2,2,2-trifluoroacetophenone, trifluoroacetyl-1-naphthalene, and trifluoroacetyl-2-naphthalene are all reduced with 1 within 1–3 d at rt in 90% ee, 78% ee and 91% ee, respectively. The optical purity of 1-phenyl-2,2,2-trifluoroethanol is upgraded to ≥99% ee by crystallizing the initially formed product from pentane. 1,1,2,2,2-Pentafluoropropiophenone and 1,1,2,2,3,3,3,-heptafluorobutyrophenone are reduced in 3 d with 1 to the corresponding alcohols in 92% ee and 87% ee, respectively. The reagent reduces alkyl trifluoromethyl ketones at a rate faster than that of the aryl derivatives, while still providing the product alcohols in very high ee. Thus, 1,1,1-trifluoroacetone, 1,1,1-trifluorononan-2-one, and 1,1,1-trifluorodecan-2-one are all reduced within 4–8 h in 89% ee, 92% ee, and 91% ee, respectively. Even α-sec-alkyl trifluoromethyl ketones are handled by 1 very efficiently. Thus cyclohexyl trifluoromethyl ketone is reduced by 1 at rt in 12 h to the product alcohol in 87% ee. In all of these cases the trifluoromethyl group acts as the enantiocontrolling larger group as compared to the aryl or alkyl group. This produces alcohol products with stereochemistry opposite to those obtained for the corresponding hydrogen analogs. The steric and electronic influence of the trifluoromethyl group in achieving enantiocontrol in asymmetric reductions is discussed.
Magnetization instability driven by spin torques

Electric currents in a ferromagnet film produce adiabatic and nonadiabatic torques on magnetization. When the current density is sufficiently large, these torques drive the uniform magnetization into spatially and temporally chaotic motion of magnetization. We predict several key characteristics of the magnetization instability by calculating the current-induced domain wall creation, annihilation and dynamics.
Dual-color fluorescence fluctuation spectroscopy in vitro and in vivo

The combination of dual-color fluorescence correlation spectroscopy (FCS) and two-photon excitation is a powerful tool for probing protein-protein interactions. The submicron resolution and single molecule sensitivity of the technique make it attractive for in vivo applications. However, the strong spectral cross talk between the two emission channels of most fluorescent dye mixtures provides a challenge for the analysis of dual-color FCS experiments. We describe a new technique, dual-color photon counting histogram (PCH) analysis that overcomes some of the challenges associated with spectral cross talk. Dual-color PCH is an extension of regular PCH that simultaneously analyses the photon counts of two detection channels. We demonstrate that dual color PCH quantitatively resolves protein mixtures in vitro. We also apply dual-color PCH to study proteins in biological cells. The fluorescent proteins ECFP and EYFP, which are commonly used for dual-color studies in cells, have significant spectral cross talk. We will discuss the resolvability of these fluorescent proteins and present data that successfully resolve the protein mixtures in vitro and in vivo. Our results show that dual color PCH is a promising technique for the characterization of protein-protein interactions in intact cells.
The New and Given in Children's Comprehension of Presuppositive Negatives in Two Modes of Processing

The purpose of this study was to determine whether or not children, grades 2, 4, and 6, make consistent use of the Given-New Strategy (cf. Haviland & Clark, 1974) in visually and aurally comprehending pre-suppositive negatives. Following de Boysson-Bardies' (1977) procedure of having children manifest their interpretation of the scope of the negative under different sentential definite-indefinite article conditions by graphically representing nonnegated subjects and/or objects, it was found that children tend to treat more information as Given when aurally processing than when visually processing. And conversely, children tend to treat more information as New when visually processing than when aurally processing. The significance of these findings are discussed in terms of ordinal and nominal interpretations of levels-of-processing.
Ball lightning project

Summary form only given. In the following up of our initial work on ball lightning, we have developed a special camera for photographing the initial stroke of a lightning discharge. The object is to obtain time resolved photographs of the closed current loops observed in sparkovers in the Holifield 25 MV, DC accelerator at the Oak Ridge National Laboratory. The apparatus comprises a commercial lightning photographic trigger that opens a camera shutter on reception of a light pulse from a lightning discharge. In the commercial configuration, the inherent time delay in the camera's shutter mechanism causes the camera to miss the initial lightning stroke. However, in nature, lightning in general has several strokes, and so the camera captures the second and subsequent strokes. In our modification, the lightning image is focused on a semi-transparent disc coated with a phosphor having a time constant of about a second. This disc provides a temporary image storage mechanism while the camera shutter is being activated. Test photographs of pulsed light sources have been quite successful. We anticipate on having experimental lightning results at the forthcoming ICOPS meeting
A taxonomic revision of Leucothoë (Ericaceae; Tribe Gaultherieae)

Leucothoe is here defined as a genus of five species (L. axillaris, L. fontanesiana, L. griffithiana, L. keiskei, and L. davisiae), occurring in eastern Asia and western and eastern North America. Generic autapomorphies include autumn-formed inflorescences with meiosis occurring in the autumn. Members of the Leucothoe clade, which are evergreen, are sister to the deciduous Eubotryoides grayana, sharing the apomorphies of winged seeds with a distinctly protuberant hilum, the former of which is homoplasious. Leucothoe axillaris and L. fontanesiana, both of eastern North America, form a closely related species pair, as do the eastern Asian L. griffithiana and L. keiskei. Leucothoe davisiae, occurring in western North America, is likely sister to the remaining species, and it differs in having erect branches and inflorescences, minutely bullate capsules, and in the lack of awns on the anthers. Species descriptions, nomenclatural information, specimen citations, and eco-geographical characterizations for these five species are presented, along with an identification key.
Adenosine, renal function and kidney viability.

To the Editor: The interesting and impeccably designed study by Erley et al convincingly demonstrates the role of adenosine and adenosine receptors in renal function1. However, their tentative conclusion, that adenosine antagonists would be effective in preventing renal impairment following radiocontrast-medium administration is not justified by the study and may be wrong. There is a fundamental difference between renal function and renal viability. Adenosine constricts pre-glomerular vessels and dilates post-glomerular vessels (via A1 and A2 receptors, respectively)2,3,4,5. This results in a significant decrease in intra-glomerular pressure and a decrease in glomerular filtration rate. This is exactly what the authors observed. However, a decrease in glomerular filtration would result in a decrease in solute delivery to the tubulae, a decrease in the tubular reabsorption, and a decrease in oxygen demand in the medulla3. In addition, adenosine also appears to decrease sodium chloride transport in the thick ascending limb of Henle's loop3 as well as to increase blood flow to the medulla by dilating the vasa recta (abstract; Clin Res 36:627A, 1988). Adenosine administration results in a significant increase in medullary PO2 (in conjunction with a decrease in cortical PO2)5.
The Torch Stops Here: Olympic Sponsorship and Corporate Reputation

This study examines how corporate involvement in the Olympic Games enhances corporate reputation. We investigate the impact on companies of sponsoring the Olympics, the magnitude of sponsorship, and the duration of sponsorship on corporate reputation. After controlling for financial performance, our results indicate that Olympic sponsorship greatly impacts and positively improves corporate reputation. Length of sponsorship and monetary level of sponsorship do not appear to have a significant effect on our measure of corporate reputation.
Analysis of the role of fluids in causing fractures in the Spraberry Trend, Midland Basin

The Spraberry Formation in west-central Texas is a highly fractured formation with both extension and shear fractures. At least two sets of natural fractures exist in two reservoir intervals. We have considered two possible origins for the fracturing: (i) high fluid pressure plus tectonic stress and (ii) tectonic stress at near-hydrostatic fluid pressure. Reconstruction of geologic, thermal and hydrodynamic histories suggests that high fluid pressures probably did not occur during the basin’s history. To explore the second hypothesis, we developed and applied a calibrated, discrete-element model of Spraberry strata to investigate whether weak Laramide compressional forces could cause fractures in the absence of high fluid pressures. Simulation results suggest that a mild compressional episode of geologically short duration may indeed have induced conjugate shear fractures.