cssi/SciSciGPT-SciSciNet huggingface dataset:
A transient interaction between the phosphate binding loop and switch I contributes to the allosteric network between receptor and nucleotide in Gαi1.

Receptor-mediated activation of the Gα subunit of heterotrimeric G proteins requires allosteric communication between the receptor binding site and the guanine nucleotide binding site, which are separated by >30 Å. Structural changes in the allosteric network connecting these sites are predicted to be transient in the wild-type Gα subunit, making studies of these connections challenging. In the current work, site-directed mutants that alter the energy barriers between the activation states are used as tools to better understand the transient features of allosteric signaling in the Gα subunit. The observed differences in relative receptor affinity for intact Gαi1 subunits versus C-terminal Gαi1 peptides harboring the K345L mutation are consistent with this mutation modulating the allosteric network in the protein subunit. Measurement of nucleotide exchange rates, affinity for metarhodopsin II, and thermostability suggest that the K345L Gαi1 variant has reduced stability in both the GDP-bound and nucleotide-free states as compared with wild type but similar stability in the GTPγS-bound state. High resolution x-ray crystal structures reveal conformational changes accompanying the destabilization of the GDP-bound state. Of these, the conformation for Switch I was stabilized by an ionic interaction with the phosphate binding loop. Further site-directed mutagenesis suggests that this interaction between Switch I and the phosphate binding loop is important for receptor-mediated nucleotide exchange in the wild-type Gαi1 subunit.
Tensile properties of cotton treated with alkali metal hydroxides

The tenacity of cotton fibers treated without tension with 5N KOH at 0°C or 21°C is greater than that of fibers treated with either 5N LiOH or NaOH. In studying the effect of changes in fine structure on the strength of cotton fibers, we suggest that strength should be given as breaking load rather than as tenacity. Evidence is given indicating that crystallite length is an important factor and should be considered with degree of crystallinity and degree of orientation when explaining the increase in breaking load of cotton fibers brought about by treatment with 5N alkali metal hydroxides.
Functional domains of cell adhesion molecules.

A number of molecules involved in cell adhesion (e.g. fibronectin, laminin, collagens I and IV, thrombospondin, entactin) have now been identified and the consequent roles that they play in the processes of growth, migration, differentiation and tumor spread have been described. Active sequences of the molecules have been identified using synthetic peptides derived from specific domains. Several adhesive molecules contain multiple active domains with different biological activities.
Using metal-catalyzed oxidation reactions and mass spectrometry to identify amino acid residues within 10 A of the metal in Cu-binding proteins.

Metal-catalyzed oxidation (MCO) reactions and mass spectrometry (MS) can be used together to determine the amino acids bound to Cu in a metalloprotein. Selective oxidation of only amino acids bound to Cu during the MCO/MS approach relies on proper choice of the types and concentrations of the reducing and oxidizing agents. We show here that if these MCO reagent concentrations are “detuned” or varied slightly from optimal conditions, nonmetal-bound amino acids close to Cu can also be oxidized in a controlled manner. Using Cu/Zn superoxide dismutase as a model system, we demonstrate that amino acids up to 10 A from Cu can be modified as long as they are readily accessible to diffusing reactive oxygen species. UV/VIS spectroscopy and measurements of oxidation kinetics provide evidence that the protein’s structural integrity around Cu is maintained during the detuned MCO reactions. Because this method can identify amino acids around Cu that have low solvent accessibility, it should complement other radical-based protein surface-mapping techniques.
Schistosoma mansoni: ingestion of dextrans, serum albumin, and IgG by schistosomula.

Schistosomula of Schistosoma mansoni develop the ability to ingest and digest red blood cells after the fourth day post-transformation. Here, we have used fluorescently-labeled dextrans and two plasma proteins, albumin and IgG, to test whether day-old schistosomula can ingest and process macromolecules prior to the time that they eat red cells. Worms ingested dextrans of molecular weights 4,000, 70,000, and 2 × 106 in a time- and concentration-dependent manner. The dextran remained in the cecal lumen for up to 2 days after feeding. Parasites ingested both fluorescein-conjugated bovine serum albumin and rabbit IgG, but neither of these proteins remained confined to the cecum over time. Instead, fluorescence redistributed to the acetabular glands within a few hours. Thin-layer chromatography indicated that schistosomula degraded fluorescein-conjugated albumin to fluorescein-conjugated peptides approximately 10–15 amino acids long. The volume of the cecum was estimated to be 2431 μm3 and the surface area 299 μm2. These results demonstrate that larval schistosomes can ingest both proteins and complex carbohydrates shortly after transformation, before they can ingest red cells. Further, the gut apparently releases proteases that cleave plasma proteins, but not saccharidases that cleave dextran.
Purification and properties of a ribonuclease isolated from etiolated cucumber seedlings.

Abstract A ribonuclease was purified from extracts of germinating etiolated cucumber seedlings by acidification, adsorption, and elution on Bio-Rex-70, and by chromatography on diethylaminoethyl and carboxymethyl celluloses. The enzyme migrated as a single component when examined by polyacrylamide gel electrophoresis at pH 4.5 and 8.3, and precipitated as a single band in 0.75% agar when reacted with its homologous antiserum. The enzyme possessed optimal activity between pH 5 and 6 (maximum at pH 5.6) and at an ionic strength of 0.15 m NaCl. It was heat-stable in weakly acidic solutions and could be heated for 16 minutes at 100 ° without complete loss of activity. Its molecular weight was “approximately 12,600 ( s 20. w = 1.5S, and D, from immunodiffusion, = 11 × 10 −7 cm 2 sec −1 ).” Like other plant nucleases, cucumber ribonuclease appeared to show less specificity than pancreatic or Takadiastase counterparts.
Long-term radiographic outcomes of microemboli following carotid interventions

Objective Subclinical microemboli on diffusion-weighted magnetic resonance imaging (DWI) have been identified immediately following carotid revascularization procedures, but the clinical significance and long-term effects are largely unknown. The purpose of this study was to evaluate long-term radiographic outcomes of these DWI lesions. Methods Patients who underwent perioperative magnetic resonance imaging (MRI) evaluations for carotid interventions at a single institution from July 2004 to December 2008 were evaluated, particularly those who had additional follow-up MRI. DWI with apparent diffusion coefficient (ADC), fluid-attenuated inversion recovery (FLAIR), and T2-weighted MRI images were compared to determine long-term effect of microemboli. Results One-hundred sixty-eight consecutive patients (68 carotid artery stenting [CAS] and 100 carotid endarterectomy [CEA]) who received perioperative MRI were included. All CAS were performed with an embolic protection device. The incidence of microemboli was significantly higher in the CAS group than the CEA group (46.3% and 12%, respectively, P Conclusions The majority of microemboli do not have long-term radiographic sequelae. Size and hyperintensity on postoperative FLAIR are predictive of residual brain structure abnormality, and further neurocognitive evaluations are warranted.
Design of a Magnetic Field-Based Multi Degree-of-Freedom Orientation Sensor Using the Distributed-Multiple-Pole Model

Precision control of a tiltable spinning shaft requires real-time measurement of the inclination. Conventional single-axis encoders, though capable of providing high-resolution (linear or angular) measurements, rely on mechanical linkages (that often introduce frictions, backlashes, and singularities) to constrain the device so that the three-DOF motion can be deduced from the individual orthogonal measurements. Vision-based sensors, which have the attractive features of being non-contact, are limited to low speed measurements. We present here an efficient method for designing a magnetic field-based orientation sensor for devices where orientation control of a rotating shaft under the influence of a magnetic field is required. The ability to characterize the magnetic fields and forces in addition to orientation sensing can offer a number of advantages in real-time computation and control.Copyright © 2007 by ASME
Chemokines and inflammation in the nasal passages of infants with respiratory syncytial virus bronchiolitis.

Abstract This study measured chemokines in nasal lavage fluids (NLF) from infants with respiratory syncytial virus (RSV) bronchiolitis, defined by lung hyperinflation and wheezing. Comparison was made to RSV-positive infants without bronchiolitis and RSV-negative infants with acute respiratory illnesses. RSV-positive illnesses were associated with increased epithelial shedding, increased RANTES/protein ratios, and increased IL-8/protein ratios in NLF compared to RSV-negative illnesses. Among RSV-positive infants, bronchiolitics had greater total cell counts and percentage epithelial cells in NLF than nonbronchiolitics. Bronchiolitics also had roughly twice the NLF RANTES/IL-8 ratio than nonbronchiolitics ( P = .043). Semiquantitative reverse transcriptase–polymerase chain reaction of nasal epithelium suggested similar RANTES/IL-8 ratio increases among bronchiolitics. A more mildly affected, RSV-positive outpatient population showed none of these differences. We conclude that RSV bronchiolitis is associated with a shift toward relatively more RANTES in nasal secretions of infants sick enough to require hospitalization, and mucosal epithelium may contribute to this process. Similar processes in the lower airways may enhance inflammation due to RANTES-responsive cell types and affect clinical manifestations.
Segregation of Cu in Cu (Ti) alloys during nitridation in NH3

Abstract Cu(Ti 27 at.%) alloys on SiO2 were reacted in NH3 for 30 min over the temperature range 400–700 °C. Rutherford backscattering spectrometry in conjunction with high resolution transmission electron microscopy were utilized to investigate reaction products. At 400–450 °C, Ti is observed to segregate to the free surface to react with NH3, forming an Ti oxynitride layer. Above 500 °C, Ti segregates to both the free surface and to the alloy/SiO2 interface, leaving relatively-pure Cu layer. Reaction between Ti and SiO2 results in a TiO Ti 5 Si 3 bilayer structure. By use of high spatial resolution energy dispersive X-ray spcctroscopy, the presence of a Cu-containing layer at the TiO Ti 5 Si 3 interface is observed. This layer may also contain Ti, Si and/or O. We propose a mechanism for Cu segregation to this interface which requires Cu diffusion across TiO and subsequent dissociation of Ti5Si3. Thermodynamic calculations support this mechanism.
The parameter identification problem for the somatic shunt model

The somatic shunt model, a generalized version of the Rall equivalent cylinder model, is used commonly to describe the passive electrotonic properties of neurons. Procedures for determining the parameters of the somatic shunt model that best describe a given neuron typically rely on the response of the cell to a small step of hyperpolarizing current injected by an intrasomatic recording electrode. In this study it is shown that the problem of estimating model parameters for the somatic shunt model using physiological data is ill-posed, in that very small errors in measured data can lead to large and unpredictable errors in parameter estimates. If the somatic shunt is assumed to be a real property of the intact neuron, the effects of these errors are not severe when predicting EPSP waveshapes resulting from synaptic input at a given location. However, if the somatic shunt is assumed to be a consequence of a leakage pathway around the recording electrode, and a correction for the shunt is applied, then the instability of the inverse problem can introduce large errors in estimates of EPSP waveshape as a function of synaptic location in the intact cell. Morphological constraints can be used to improve the accuracy of the inversion procedure in terms of both parameter estimates and predicted EPSP responses.
Effects of Synaptic Connectivity Inhomogeneities for Propagation of Activity in Neural Tissue

The study of traveling waves of activity in neural tissue can provide deep insights into the functions of the brain during sensory processing or during abnormal states such as epilepsy, migraines or hallucinations. Computational models of these systems usually describe the tissue as a vast interconnected network of neurons comprised of large number of units with similar properties, for example integrate and fire neurons. It is also widely assumed that while the strength of the connections between neurons changes as a function of distance, this interaction does not depend on other local parameters. These assumptions allow for formulation of a set of integro-differential equations describing the propagation of the traveling wave fronts in a one-dimensional integrate-and-fire network of synaptically coupled neurons, allowing for investigation of the network dynamics during wave initiation and propagation. Equations for the transition between initiation and transition toward constant speed traveling waves have been derived for Gaussian connectivity [1] and finite support connectivity [2]. These results have been also confirmed through numerical simulations, leading to methods for optimizing and improving simulations of large-scale networks [3]. These results have been extended beyond the simpler case of one-spike activity propagation, deriving equations for constant speed waves with a finite and infinite number of spikes [4]. This framework has produced insight on the mechanisms of stable constant-speed traveling wave solutions, but the study of inhomogeneities in synaptic connections likely to exist in the brain tissue has received much less attention since not surprisingly, the presence of inhomogeneities vastly increases the complexity of the mathematical models. However, recent work [5,6] used homogenization theory to determine how inhomogeneities can induce propagation failure. We extended our previous models that exhibit constant-speed traveling waves to investigate how the presence of these inhomogeneities affects the relationship between the speed of the activity propagation and its acceleration. We determine that the estimates from homogenization theory do not accurately capture the conditions for propagation failure. More precisely, just prior to stopping, the activity propagates at a higher average speed than predicted from the theoretical results of the homogenization theory. We derive more precise estimates for the conditions when propagation failure occurs. Furthermore, our study points to directions where researchers can obtain additional tools for analyzing experimental data in order to infer details of synaptic connectivity.
Evaluating changes and estimating seasonal precipitation for the Colorado River Basin using a stochastic nonparametric disaggregation technique

[1] Precipitation estimation is an important and challenging task in hydrology because of high variability and changing climate. This research involves (1) analyzing changes (trend and step) in seasonal precipitation and (2) estimating seasonal precipitation by disaggregating water year precipitation using a k-nearest neighbor (KNN) nonparametric technique for 29 climate divisions encompassing the Colorado River Basin. Water year precipitation data from 1900 to 2008 are subdivided into four seasons (i.e., autumn, winter, spring, and summer). Two statistical tests (Mann-Kendall and Spearman's rho) are used to evaluate trend changes, and a rank sum test is used to identify the step change in seasonal precipitation. The results indicate a decrease in the upper basin and an increase in the lower basin winter precipitation resulting from an abrupt step change. The effect of El Nino–Southern Oscillations in relation to seasonal precipitation is also evaluated by removing the historic El Nino events. Decreasing winter and spring season precipitation trends for the upper basin are not linked to El Nino. Corroborating evidence of changes in seasonal precipitation is established by analyzing the trends in snow telemetry (SNOTEL) data and streamflow at the Lees Ferry gauge. KNN disaggregation results indicate satisfactory seasonal precipitation estimates during winter and spring seasons compared to autumn and summer seasons, and the superiority of KNN results is established when compared with the first-order periodic autoregressive parametric approach. The analysis of seasonal changes and estimates of precipitation can help water managers to better manage the water resources in the Colorado River Basin.
Reconstructability considerations with arbitrary data

Abstract The advent of the Klir system has greatly expanded the realm of applicability of reconstructability analysis. Theoretically reconstructability analysis can be applied to general multivariate data. However, real world data will usually contain impediments to the use of the Klir system. This paper identifies these impediments, and methodology for their resolution is given.
Attention-reactive user interface for sensemaking

I will talk about an emerging class of user interfaces that if not exactly intelligent are at least attention-reactive. They are being developed to handle "sensemaking" tasks, in which users find, analyze, and creation products or action from large collections of documents. Applications might be expected to develop in law, education, scholarship, security, and medicine. These interfaces have a focus + context visualization on the front end and a semantic contextual computing engine on the back end. Ultimately they can be expected to have mixed initiatives. These interfaces require the development of a supporting science of human information interaction that stresses interaction between the user and information and deemphasizes the platform through which this occurs.
Initial Reliability and Validity of the BASC-2, SRP, College Version

With the growing number of college students seeking mental health services, it is imperative to have accurate assessment tools. One new measure, the Behavior Assessment System for Children-2, Self-Report of Personality, College Version (SRP-CV), has yet to be independently researched. This study examines the test—retest reliability of the SRP-CV. Convergent and discriminant validity are explored through multivariate analyses. Results indicate that the SRP-CV shows strong temporal stability. Several of the SRP-CV scales also correlate highly with other well-researched self-report measures. Overall, the SRP-CV shows promise as a multidimensional measure of behavior and personality. It makes a unique contribution to the arsenal of self-report measures currently available to clinicians working with the college population.
Nanoscale indent formation in shape memory polymers using a heated probe tip

This paper presents experimental investigation of nanoscale indentation formation in shape memory polymers. The polymers were synthesized by photopolymerizing a tert-butyl acrylate (tBA) monomer with a poly(ethylene glycol dimethacrylate) (PEGDMA) crosslinker. The concentration and the molecular weight of the crosslinker were varied to produce five polymers with tailored properties. Nanoscale indentations were formed on the polymer surfaces by using a heated atomic force microscope (AFM) cantilever at various temperatures near or above the glass transition (between 84 and 215 °C) and a range of heating durations from 100 µs to 8 ms. The images of the indents were obtained with the same probe tip at room temperature. The contact pressure, a measure of transient hardness, was derived from the indentation height data as a function of time and temperature for different polymers. With increasing crosslinker molecular weight and decreasing crosslinker concentration, the contact pressures decreased at a fixed maximum load due to increased crosslink spacing in the polymer system. The results provide insight into the nanoscale response of these novel materials.
The Impact of Satellite Soundings on the National Meteorological Center's Analysis and Forecast System—The Data Systems Test Results

Parallel analyses produced with (SAT) and without (NOSAT) the sounding data from the experimental Nimbus-6 and operational NOAA-4 satellites for two data system test periods have indicated that satellite soundings had little impact on forecast through 72 h over the Northern Hemisphere. The effect of remote temperature sounding was generally small and of inconsistent sign, i.e. beneficial in some cases, harmful in others. These positive and negative contributions averaged slightly positive for test period 6 and slightly negative for test period 5. Because of the inconsistency in sign, neither result is much of meteorological consequence. There were, however, systematic differences between the SAT and NOSAT mode analysis: the amplitude of weather systems was consistently less in the SAT mode. The reduced amplitude reflects a tendency for the satellite temperature retrievals to underestimate the spatial variance in the thermal structure of the atmosphere.
Design and Control of a Force-Reflecting Haptic Interface for Teleoperational Grasping

In this paper the design of a multi-finger force-reflecting haptic interface device for teleoperational grasping is introduced. The haptic interface or master controller device is worn on the human operator's hand and measured human finger positions are used to control the finger positions of a remote grasping manipulator or slave device. The slave may be a physical robotic grasping manipulator, or a computer generated representation of a human hand such as used in virtual reality applications. The forces measured by the robotic slave, or calculated for the virtual slave, are presented to the operator's fingertips through the master providing a means for deeper human sensation of presence and better control of grasping tasks in the slave environments. Design parameters and performance measures for haptic interfaces for teleoperation are discussed. One key performance issue involving the high-speed display of forces during initial contact, especially when interacting with rigid surfaces, is addressed by the present design, reducing slave controller computation requirements and overcoming actuator response time constraints. The design presented utilizes a planar four-bar linkage for each finger to represent each finger bend motion as a single degree of freedom, and to provide a finger bend resistance force that is substantially perpendicular to the distal finger pad throughout the full 180 degrees of finger bend motion represented. The finger linkage design, in combination with a remote position measurement and force display assembly, provides a very lightweight and low inertia system with a large workspace. The concept of a replicated finger is introduced which, in combination with a decoupled actuator and feed forward control, provides improved performance in transparent free motion, and rapid, stable touch sensation of initial contact with rigid surfaces. A distributed computation architecture with a PC based haptic interface controller and associated control algorithms are also discussed.
On Institutional Obsolescence and Innovation—Background for Professional Dialogue on Public Policy

explanation of its purpose is as follows: "This is a base paper for discussions at the annual meeting of AAEA in Lexington, Kentucky, in August, including a panel concluding the meeting. In addition, contributed papers commenting on this paper are invited. Selected ones will be accepted for presentation at the meeting." These papers must adhere to the rules for contributed papers as they were announced in the February Journal, except that (for these papers only) the due date is on or before July 1 and only three copies are required. See announcements section for an additional supplementary note on contributed papers.
Pathology of fatty liver disease

Fatty liver disease is currently recognized as a common cause of liver test elevation, paralleling the worldwide 'epidemic' of obesity in adults and children. In many clinical practices, there is recognition that liver biopsy evaluation is the only means of diagnosis (or exclusion) of fatty liver disease, as neither laboratory tests nor imaging studies to date can provide complete data related to amount of steatosis, inflammation, liver cell injury, fibrosis, and architectural remodeling. Liver biopsy evaluation also provides a means of 'grading and staging' the lesions of fatty liver disease and of detecting clinically unsuspected processes. Liver biopsy evaluation is often the primary end point in clinical trials of treatment, thus, standardization of diagnosis and methods of grading and staging have become important. In this review, these concepts as well as the pathophysiologic bases for them are discussed.
EUV detection of high-frequency surface acoustic waves

We use coherent extreme ultraviolet radiation to probe surface acoustic wave propagation in nickel-on-sapphire nanostructures. We observe no acoustic dispersion over SAW wavelengths down to 200nm, meaning the SAW propagation is unaffected by the nanostructure.
Large-signal numerical and analytical HBT models

Several large-signal heterojunction bipolar transistor (HBT) models are investigated to determine their usefulness at millimeter-wave frequencies. The most detailed model involves numerically solving moments of the Boltzmann transport equation. A description of the numerical model is given along with several simulated results. The numerical model is then used to evaluate two analytical HBT models, the conventional Gummel-Poon model and a modified Ebers-Moll model. It is found that the commonly used Gummel-Poon model exhibits poor agreement with numerical and experimental data at millimeter-wave frequencies due to neglect of transit-time delays. Improved agreement between measured and modeled data results b including transit-time effects in an Ebers-Moll model. The simple model has direct application to millimeter-wave power amplifier and oscillator design. Several measured results are presented to help verify the simple model. >
The other side of the social web: a taxonomy for social information access

The power of the modern Web, which is frequently called the Social Web or Web 2.0, is frequently traced to the power of users as contributors of various kinds of contents through Wikis, blogs, and resource sharing sites. However, the community power impacts not only the production of Web content, but also the access to all kinds of Web content. A number of research groups worldwide explore what we call social information access techniques that help users get to the right information using "collective wisdom" distilled from actions of those who worked with this information earlier. This invited talk offers a brief introduction into this important research stream and reviews recent works on social information access performed at the University of Pittsburgh's PAWS Lab lead by the author.
ON LAND SLIDE DETECTION USING TERRASAR-X OVER EARTHEN LEVEES

Earthen levees have an important role to protect large areas of inhabited and cultivated land in the US from flooding. Failure of the levees can threaten the loss of life and property. One of the problems which can lead to a complete failure during a high water event is a slough slide. In this research, we are trying to detect such slides using X-band SAR data. Our methodology consists of the following four steps: 1) segmentation of the levee area from background; 2) extracting features including backscatter features and texture features; 3) training a back propagation neural network classifier using ground-truth data; and 4) testing the area of interest and validation of the results using ground truth data. A dual-polarimetric X-band image is acquired from the German TerraSAR-X satellite. Ground-truth data include the slides and healthy area. The study area is an approximately 1 km stretch of levee along the lower Mississippi River in the United States. The output classification shows the two classes of healthy and slide areas. The results show classification accuracies of approximately 67% for detecting the slide pixels.
Phase-Guided Scheduling on Single-ISA Heterogeneous Multicore Processors

Single-ISA heterogeneous (also known as asymmetric) multicore processors offer significant advantages over homogenous multicores in terms of both power and performance. Power-efficient cores can be paired with higher-performance cores to achieve advantageous power/performance tradeoffs. Unfortunately, such processors also create unique challenges in effective mapping of processes to cores. The greater the diversity of cores, the more complex this problem becomes. Previous scheduling approaches sample performance while permuting the schedule across each type of core each time a change in application behavior is detected. However, approaches that require frequent sampling of the performance of threads (or combinations of threads) on each core may be impractical. We propose scheduling threads on a heterogeneous multicore processor using not just the detection of a change in program behavior or phase, but instead an identification and recording of these phase behaviors. We highlight the correlation between the execution phases of an application and the performance of those phases on any particular core type. We present mechanisms that exploit this correlation between program phases and appropriate scheduling decisions and demonstrate near optimal mapping of thread segments to processor cores can be done without frequently sampling the performance of each thread on each processor core type.
Les métalloprotéases matricielles et leurs inhibiteurs synthétiques dans la progression tumorale

Les metalloproteases matricielles (MMP) constituent une famille de proteases impliquees dans la degradation proteolytique de nombreuses proteines de la matrice extracellulaire mais aussi de proteines non matricielles. Ces proteases jouent un role important et complexe dans plusieurs etapes de la progression cancereuse telles que la croissance tumorale, la proliferation des cellules cancereuses et leur caractere invasif, la dissemination metastatique et l’angiogenese. Les MMP sont donc devenues des cibles potentielles dans le traitement anti-cancereux. Plusieurs inhibiteurs synthetiques ont ainsi ete developpes et ont montre une efficacite therapeutique dans plusieurs modeles animaux de cancer. Les premiers essais cliniques realises avec ces inhibiteurs chez des patients cancereux a un stade avance ont cependant montre des effets mitiges.
Note: The Newsvendor Model with Endogenous Demand

This paper considers a firm's price and inventory policy when it faces uncertain demand that depends on both price and inventory level. The authors extend the classic newsvendor model by assuming that expected utility maximizing consumers choose between visiting the firm and consuming an exogenous outside option. The outside option represents the utility the consumer forgoes when she chooses to visit the firm before knowing whether or not the product will be available. The authors investigate both the case in which the firm's price is exogenous and the case in which price is chosen optimally. The paper makes two contributions. First, the authors show that the firm holds more inventories, provides a higher fill rate, attracts more customers, and earns higher profits when it internalizes the effect of its inventory on demand. Second, the authors show that in the endogenous price case the firm's two-dimensional decision problem can be reduced to two, sequential, single-variable optimizations. As a result, the endogenous-price case is as easy to solve as the exogenous-price case.
Engineering metal-impurity nanodefects for low-cost solar cells

As the demand for high-quality solar-cell feedstock exceeds supply and drives prices upwards, cheaper but dirtier alternative feedstock materials are being developed. Successful use of these alternative feedstocks requires that one rigorously control the deleterious effects of the more abundant metallic impurities. In this study, we demonstrate how metal nanodefect engineering can be used to reduce the electrical activity of metallic impurities, resulting in dramatic enhancements of performance even in heavily contaminated solar-cell material. Highly sensitive synchrotron-based measurements directly confirm that the spatial and size distributions of metal nanodefects regulate the minority-carrier diffusion length, a key parameter for determining the actual performance of solar-cell devices. By engineering the distributions of metal-impurity nanodefects in a controlled fashion, the minority-carrier diffusion length can be increased by up to a factor of four, indicating that the use of lower-quality feedstocks with proper controls may be a viable alternative to producing cost-effective solar cells.
Radiographic findings and morbidity in patients treated with stereotactic radiosurgery

Abstract Purpose: To determine the prognostic significance of pretreatment edema, lesion size and location on morbidity following stereotactic radiosurgery (SRS). Methods and Materials: Forty-seven evaluable patients with 63 lesions were treated on a 6-MV linear accelerator radiosurgery system at Memorial Sloan Kettering Cancer Center. All patients received a 10-mg intravenous bolus of dexamethasone sodium phosphate (Decadron) prior to SRS. Thirteen patients were treated for asymptomatic lesions while 34 were treated because of neurologic symptoms. The median dose delivered was 1800 cGy and the median prescription isodose curve was 85%. Pretreatment edema was measured on a transaxial T2-weighted MR image acquired within 1 month of the SRS. Results: Ten patients experienced morbidity as a result of their treatment. The complication rate was measured by neurologic events following SRS and was not significantly influenced by the extent of peritumoral edema. Lesion size was also unrelated to the development of post-treatment symptoms as assessed by the ease of tapering steroids. The only parameter found to influence post-SRS complications was lesion location. Four of six (66%) patients treated to lesions in the motor cortex suffered post-SRS seizure activity, whereas only 6 of 37 (16%) patients treated to lesions elsewhere in the brain parenchyma experienced seizure activity. Conclusion: The presence of pretreatment edema and lesion size are not predictors of post-SRS complication rates or the ability to taper Decadron. Lesion location is predictive of post-SRS seizure activity.
The carbon–nutrient balance hypothesis: its rise and fall

The idea that the concentration of secondary metabolites in plant tissues is controlled by the availability of carbon and nitrogen in the environment has been termed the carbon–nutrient balance hypothesis (CNB). This hypothesis has been invoked both for prediction and for post hoc explanation of the results of hundreds of studies. Although it successfully predicts outcomes in some cases, it fails to such an extent that it cannot any longer be considered useful as a predictive tool. As information from studies has accumulated, many attempts have been made to save CNB, but these have been largely unsuccessful and have managed only to limit its utility. The failure of CNB is rooted in assumptions that are now known to be incorrect and it is time to abandon CNB because continued use of the hypothesis is now hindering understanding of plant–consumer interactions. In its place we propose development of theory with a firm evolutionary basis that is mechanistically sophisticated in terms of plant and herbivore physiology and genetics.
New Pathways Towards the Enhancement of the Image Quality

In this paper, experimental results and data analysis on a novel technique aimed at increasing the image quality of the target, surrounded by a scattering medium, is presented. Specifically, enhanced target detection has been obtained by doping the surrounding medium with molecular contrast agents, consisting polar molecules yielding to an enhanced contract and specificity of the target, utilizing advanced polarimetric imaging techniques.
Learning the Structure of Sum-Product Networks

Sum-product networks (SPNs) are a new class of deep probabilistic models. SPNs can have unbounded treewidth but inference in them is always tractable. An SPN is either a univariate distribution, a product of SPNs over disjoint variables, or a weighted sum of SPNs over the same variables. We propose the first algorithm for learning the structure of SPNs that takes full advantage of their expressiveness. At each step, the algorithm attempts to divide the current variables into approximately independent subsets. If successful, it returns the product of recursive calls on the subsets; otherwise it returns the sum of recursive calls on subsets of similar instances from the current training set. A comprehensive empirical study shows that the learned SPNs are typically comparable to graphical models in likelihood but superior in inference speed and accuracy.
A look back at a successful year

As we approach the end of the year, we are pleased that the American Journal of Physiology-Regulatory, Integrative and Comparative Physiology has enjoyed another successful year. Although it can be difficult to obtain a true idea of what impact our Journal is having, there are many indicators we
Usefulness of QRS prolongation in predicting risk of inducible monomorphic ventricular tachycardiain patients referred forelectrophysiologic studies

QRS prolongation on surface electrocardiography has been identified as a marker for increased cardiac mortality. A potential mechanism for increased mortality is ventricular tachycardia (VT). This study aimed to evaluate the relation between bundle branch block and sustained monomorphic VT inducibility in patients referred for electrophysiologic studies. We analyzed a cohort of 777 patients (age 63 ± 18 years, 67% men, left ventricular [LV] ejection fraction [EF] 45% ± 16, prior myocardial infarction 41%) referred for electrophysiologic studies between 1994 and 2001 who underwent programmed stimulation for VT. Forty-five percent of patients were referred for syncope or a history of VT and/or ventricular fibrillation. Thirty-one percent of patients had prolonged QRS duration (≥120 ms). Patients with prolonged QRS duration were older, had lower LVEFs, and were more likely to have a history of myocardial infarction. Prolonged QRS was a significant predictor of sustained monomorphic VT inducibility (p <0.0001). On multivariate analysis correcting for age, sex, LVEF, history of myocardial infarction, medications, and QRS conduction delay proved to be independently associated with sustained monomorphic VT inducibility (relative risk 3.290, 95% confidence interval 2.185 to 4.953 for prolonged vs normal QRS duration). Thus, a prolonged QRS duration on surface electrocardiography is a strong, independent predictor of inducible sustained monomorphic VT. Conduction delay may be an important risk factor, providing a substrate for the development of reentrant monomorphic VT, and furthermore suggests a potential mechanism for the increased mortality observed in patients with prolonged QRS.
Looking for diamonds in the desert - extending automatic protocol generation to three-party authentication and key agreement protocols

We describe our new results in developing and extending Automatic Protocol Generation (APG), an approach to automatically generate security protocols. We explore two-party mutual authentication and key agreement protocols, with a trusted third party (TTP) which shares a symmetric key with each of the two principals. During the process, we experienced the challenge of a gigantic protocol space. Facing this challenge, we develop more powerful reduction techniques for the protocol generator. We also develop new pruning theorems and probabilistic methods of picking goal orderings for the protocol screener, Athena, which greatly improve the efficiency and worst-case performance of Athena. In our first experiment, APG found new protocols for two-party mutual authentication with a TTP using symmetric keys. In our second experiment, APG also found new protocols for three different sets of security properties for two-party authentication and key agreement. Our new list of security properties for key agreement also uncovered an undocumented deficiency in the Yahalom protocol.
Roy’s Adaptation Model

This column presents a dialogue with three Roy scholars. They discuss research, practice, administration, and education issues in nursing from a Roy perspective and present data on curriculum in schools across the United States in relation to the use of nursing theory and Roy's model.
Alternative Minimum Tax And Effective Returns From Municipal Bonds

Taxpayers must pay the alternative minimum tax (AMT) if a minimum tax rate applied to a broad measure of income results in an amount greater than the regular tax. The AMT rate is 20 percent for corporations and 24 percent for other taxpayers. Currently, this broad measure of income includes 100 percent of private activity bond interest and, for corporations, encompasses up to 75 percent of other tax-exempt interest. This paper explains the computation of the AMT and shows the effect of the AMT on after-tax yields from investment in municipal securities. In particular, it demonstrates that the after-tax return on municipal bonds declines with an increase in the number of years until the AMT credit resulting from previous years AMT paid is utilized. The paper then analyzes the AMT in terms of the tax clientele it creates and the implicit tax it may reduce.
Isoelectric Focusing of Muscle Proteins

It has become customary to start reviews with a statement explaining why it has been impossible to encompass all the relevant literature in one short review, while presenting the basis for selection of those papers which are mentioned. This review is an exception; the references include every paper indexed under both “isoelectric focusing” and “muscle protein” since the former term came into general use, as well as a few others that have come to our attention in spite of their failure to be unearthed by the computer. Thus, any omissions represent failures of the indexers and/or this author to achieve complete coverage of this small branch of the literature rather than careful selections based on some arbitrary judgment of the merit or significance of a report.
Block Tridiagonal Matrices and a Beefed-up Version of the Ehrenfest Urn Model

The very classical Ehrenfest urn model can be solved exactly in terms of Krawtchouk polynomials. I consider a natural extension of this model which goes beyond “nearest neighbours” random walks and whose analysis benefits from the study of a family of matrix-valued orthogonal polynomials. This subject was started by M.G. Krein around 1949. This paper shows one more example of his vast and lasting legacy in the never-ending task of finding new mathematical tools to analyze the physical world.
Temperature-sensitive transport of glycoproteins to the surface of a variant mouse lymphoma cell line.

Abstract The expression of mouse mammary tumor virus (MMTV) glycoproteins on the surface of stably infected mouse lymphoma cell line W7MG1 is dramatically increased by glucocorticoid hormones. A variant cell line, W7M.TS1, was selected from W7MG1 for its lack of expression of MMTV glycoproteins on the cell surface in response to treatment with glucocorticoid. Hormonal stimulation of MMTV RNA levels and hormone-induced cytolysis occurred normally in the variant cells. Furthermore, the rates of production of the precursor and mature forms of MMTV glycoproteins in the presence of glucocorticoid were similar in variant and wild-type cells. However, the accumulation of MMTV glycoproteins on the cell surface after hormone treatment was delayed by about 8 h in the variant relative to wild-type cells. The steady-state level of a constitutively expressed cellular protein, T200, on the variant cell surface was comparable to that on wild-type cells. However, in pulse-chase experiments, the appearance of newly synthesized T200 on the cell surface was delayed in the variant compared with wild-type cells. Another glucocorticoid hormone response, removal of H-2 class I antigens from the cell surface, was also delayed in the variant relative to wild-type cells, suggesting that turnover or internalization of cell surface glycoproteins may also be affected in the variant. The defects in the variant cell line were observed at 37 degrees C, but not at 31 degrees C; the variant cells grew normally at both temperatures. This variant phenotype defines a new genetic entity that is important for transport of glycoproteins between internal microsomal compartments and the cell surface.
Revealing particle growth mechanisms by combining high-surface-area catalysts made with monodisperse particles and electron microscopy conducted at atmospheric pressure

Abstract In situ aberration-corrected transmission electron microscopy, conducted in forming gas (5% H2/N2) at atmospheric pressure and elevated temperatures (up to 800 °C), was used to follow the growth of Pt nanoparticles dispersed on a high-surface-area Al2O3 support. These direct observations, facilitated by the use of monodisperse Pt nanoparticles, allowed for an unambiguous separation of the relative contributions of Ostwald ripening and particle migration/coalescence to the overall growth process and made possible the estimation of corresponding energetic and kinetic parameters. Whereas the parameters describing Ostwald ripening were as expected, the diffusion coefficient characterizing particle migration was surprisingly small. Size-selection methods were thus shown to have significant potential for suppressing Ostwald ripening, the dominant growth process, in practical catalysts.
Cyber Conflict Bibliography, 2015 Update

The purpose of this bibliography, originally prepared for the Future of Cyber Warfare symposium held at The George Washington University Law School in April 2012, is to provide scholarly and other resources principally focused on cyber conflict, cyber attacks, information warfare and cyber war published between 2008 and the present. Selected resources on cyber crime, cybersecurity and cyber espionage are also included.