cssi/SciSciGPT-SciSciNet huggingface dataset:
Postdispersal seed predation limits the abundance of a long-lived perennial forb (Lithospermum ruderale)

Loss of seeds to consumers is common in plant communities, but the degree to which these losses influence plant abundance or population growth is often unclear. This is particularly the case for postdispersal seed predation by rodents, as most studies of rodent seed predation have focused on the sources of spatiotemporal variation in seed loss but not quantified the population consequences of this loss. In previous work we showed that seed predation by deer mice (Peromyscus maniculatus) substantially reduced seedling recruitment and establishment of Lithospermum ruderale (Boraginaceae), a long-lived perennial forb. To shed light on how rodent seed predation and the near-term effects on plant recruitment might influence longer-term patterns of L. ruderale population growth, we combined experimental results with demographic data in stage-based population models. Model outputs revealed that rodent seed predation had a significant impact on L. ruderale population growth rate (λ). With the removal of postdispe...
Probing the Micrheology of Mesenchymal Stem Cell Migration to Tumors

Mesenchymal stem cells (MSCs) are excellent candidates for the development of cell-based gene delivery systems; however, extended cell culture, required for therapeutic development, alters MSC morphology, reducing MSC migration upon reinfusion. Spontaneous migration of MSCs to tumors is mediated by tumor secretion of proangiogenic chemokines. Multiple particle tracking microrheology was used to investigate the effect of tumor-secreted molecules on MSC viscoelasticity, which was correlated with MSC migration and morphology. Within 24 hours after MSC treatment with tumor-conditioned media (TCM), MSCs were elongated, with more than 5-fold difference in the length of lamellipodia. Within 24 hours, the migration of MSCs, measured using a Boyden chamber assay, toward TCM was increased 10-fold over control media. The mean squared displacements (MSDs) of 100-nm carboxylated polystyrene particles, injected into the cytoplasm of human MSCs using the Biolistic Particle Injection System, were determined with 33 ms temporal and 5 nm spatial resolution using multiple particle tracking. The frequency dependent elastic and viscous moduli were calculated from the complex shear moduli, which were determined from the Fourier transform of the time-dependent MSDs, using the frequency-dependent Stokes-Einstein equation. Pretreatment of MSCs with TCM resulted in rapid changes in cytoplasmic viscoelasticity with a 9.8-fold increase in the average elastic moduli, which increased from 35 to 344 dyn/cm2, and a 3.5-fold decrease in the average viscous moduli, which was reduced from 99 to 28 dyn/cm2, within 1 hour (n = 6-8 cells per group). We hypothesize that tumor-secreted molecules increase MSC mobility by altering cytoskeletal organization. Changes in MSC viscosity may be in part to reduced actin cross-linking during cytoskeletal reorganization. Increased MSC rigidity may be due to MSC elongation, which leads to the formation of polymer entanglements as the ratio of cell length to width is greatly increased.
Effects of transposition and deletion upon coat protein gene expression in bacteriophage f1

We have studied expression of the major coat (gene VIII) protein in vivo in cells infected with variant fl phage whose genomes had been restructured in vitro. This gene with its most proximal promoter and terminator behaves as an independent transcription unit: coat protein expression is unaffected by transposition of the gene to the intergenic space (IG) and is independent of orientation. Deletion of the DNA sequence (−35 region) upstream of the Pribnow box of the promoter for the transposed gene eliminates coat protein expression. The position and orientation of the transposed DNA within the IG can, however, have marked effects upon phage DNA replication. In mutants diploid for the coat protein gene, the kinetics of phage production are altered by both the level of DNA replication and the level of coat protein expression. In partial diploid mutant infections virions can be assembled from mixtures of wild-type fl and variant coat protein molecules in which amino acid polymorphisms occur near the amino terminus.
Cloning of primary human tumor colony forming units in glass capillaries

Techniques are described for growth of primary human tumor colony-forming units in agar in glass capillary tubes. Tissue recovered from an invasive procedure is made into a single cell suspension. The cells are washed and placed in tissue culture media and agar in glass capillary tubes. After 10 to 14 d of incubation, colonies of tumor cells are visible in the capillaries. This technique can be used to determine the sensitivity pattern of patients' tumors to conventional and investigational anticancer agents. The technique can also be used to screen for antitumor activity of new chemical entities.
A genetic algorithm for continuous design space search

Genetic algorithms (GAs) have been extensively used as a means for performing global optimization in a simple yet reliable manner. However, in some realistic engineering design optimization domains the simple, classical implementation of a GA based on binary encoding and bit mutation and crossover is often inefficient and unable to reach the global optimum. In this paper we describe a GA for continuous design space optimization that uses new GA operators and strategies tailored to the structure and properties of engineering design domains. Empirical results in the domains of supersonic transport aircraft and supersonic missile inlets demonstrate that the newly formulated GA can be significantly better than the classical GA in both efficiency and reliability.
Nicotine in smokers, non-smokers and room air

Abstract Nicotine is commonly observed in smokers' urine, and this circumstance was used as a means of developing atmospheric pressure ionization (API) mass spectrometric techniques for the detection of volatile components of urine which behave as bases in the gas phase. When these methods where applied in an examination of urinary bases of non-smokers who shared the laboratory areas with smokers, nicotine was found to be present to the extent of about 5% of that observed for smokers. Two routes of nicotine transfer seemed possible: water and air. The water supply was found to be nicotine-free. An air analysis method was devised; this showed that nicotine was present in the laboratory air, so that the probable route of transfer for non-smokers is through room air.
STRUCTURAL PERFORMANCE OF STORM WATER DETENTION SYSTEM WITH BUNDLED HIGH-DENSITY POLYETHYLENE PIPES

Buried parallel pipes are used for storm retention systems. Traditional retention-detention systems have spaced parallel pipes that permit soil columns between pipes. A new design allows for the parallel pipes to be placed side by side in contact with each other. The performance of such a system of bundled high-density polyethylene (HDPE) pipes that is subjected to vertical earth loads is reported. This bundled system consists of parallel HDPE pipes wrapped with a geogrid and a geofabric. The actual loads ranged from shallow cover to vertical loads equivalent to 55 ft (16.8 m) of cover. The embedment soil selected for the research was a silty sand. This soil was selected because its structural qualities are generally considered to be the least acceptable for these types of applications. The soil that typically would be specified is a crushed stone. Therefore, the results from the tests are conservative. Structural performance is reported, and photographs present the pipes in the bundled system during installation and after subjection to earth loads. Load-deflection curves for the pipes in the system are also given.
Child and Adolescent Tobacco and Substance Use within the Context of ADHD: Implications for Prevention and Treatment

Tobacco, alcohol, marijuana, and other forms of substance use among children and adolescents is a significant public health concern. At present, one high-risk population of great concern is those affected with Attention-Deficit/Hyperactivity Disorder (ADHD) and those with subthreshold ADHD-like symptoms. The prevalence of tobacco and substance use is considerable within this population, and ADHD and ADHD-like symptoms often present as comorbid conditions. To further the understanding of this problem, a review is provided of youth tobacco and substance use and their biobehavioral influences in the context of ADHD. Using primary care as an example, opportunities for tobacco and substance use prevention and treatment within this high-risk population are examined.
The development of visual expectations in the first year.

The development of expectations was investigated by using the Visual Expectations Procedure. In Experiment 1, 128 infants aged 6-, 9-, and 12-months-old saw two 40-trial sequences of a videotaped mechanical toy appearing in various locations. The sequences represented an alternation pattern (i.e., ABAB) or a complex pivot pattern (i.e., ABCBABCB). In Experiment 2, 76 infants aged 4-, 8-, and 12-months-old saw either a left-right alternation or a top-bottom alternation. Reaction time improved and the percentage of anticipations increased between 6 and 9 months in Experiment 1 and between 4 and 8 months in Experiment 2 but not thereafter. Anticipations for the pivot sequence and for younger infants on both sequences were often incorrect (i.e., gaze shifts occurred before stimulus onset but were not directed toward the upcoming stimulus). We conclude that young infants have expectations that reflect some degree of general or procedural knowledge, but it is not clear that this behavior implies specific, articulated expectations about upcoming events.
Creative Destruction: An Exploratory Study of How Digitally Native News Nonprofits Are Innovating Online Journalism Practices

As traditional news media struggle to adapt their practices to discontinuous changes resulting from technological advances, a digitally native nonprofit news model has emerged in the United States. Framed by management theories of creative destruction and disruptive innovation, this study explores how the journalists who lead these small firms view digital and social media as opportunities to revitalize public service reporting, re-create journalism practices online, and encourage consumer participation in the news-gathering process. Findings show online news entrepreneurs are strategically using their digital-first platform to focus primarily on their public service mission, engage consumers, publish information through a variety of methods and formats, collaborate with outside media, diversify revenue sources, and provide technology training to journalists and the public. ACCESS TO FULL TEXT
Memory traces in spinal cord

Abstract The complexity and inaccessibility of the vertebrate CNS impede the localization and description of memory traces and the definition of the processes that create them. Recent work has shown that the spinal stretch reflex (SSR), which is produced by a monosynaptic twoneuron pathway, can be operantly conditioned, and that memory traces responsible for this behavioral change reside in the spinal cord. The probable locations are the terminal of the Ia afferent neuron on the motoneuron and/or the motoneuron itself. Because it modifies a simple well-defined and accessible pathway, SSR conditioning may be a valuable experimental model for studying vertebrate memory.
Temperature calibration of heated silicon atomic force microscope cantilevers

Abstract This article presents calibration techniques for heated silicon atomic force microscope cantilevers and analyzes the accuracy of these techniques. A calibration methodology using Raman thermometry is presented and validated with heat transfer simulations and experimental measurements. Raman thermometry generates a calibration standard against which other techniques can be compared. Theoretical predictions of the cantilever temperature-dependent electrical properties do not by themselves provide accurate cantilever temperature calibration. Isothermal calibration is also insufficient. The temperature calibrations are stable with storage time and number of heating cycles, although an electrical ‘burn-in’ period is required to stabilize the cantilever response. These techniques for precise temperature calibration of heatable silicon cantilevers are required for applications where temperature must be carefully controlled, including surface science measurements and nano-manufacturing.
Mixed scalar glueballs and mesons

Abstract We find QCD sum rule solutions for scalar meson-glueball mixed states consistent with the f0(1500) being largely a glueball and the f0(1370) being a largely meson state, consistent with recent experiments. Pure scalar glueball solutions are in the 300–600 MeV region and pure 0 ++ q q meson solutions are found near 1 GeV.
On the Application of Eigenvector Expansions to Numerical Deconvolution

Abstract In this paper a procedure for the numerical solution of convolution-type integral equations is presented. The method uses a spectral representation of a transformed-convolution operator and can be used to solve convolution equations with casual or noncasual kernels. The formalism has the additional property of being both intuitively structured and well-suited for direct numerical computation.
The Determinants of Systematic Risk: A Synthesis

This paper contains a review and synthesis of the theoretical research that has examined the corporate determinats of systematic risk (beta). By delineating the underlying assumptions and by using a consistent notation to summarize the research results, this review is designed to facilitate the beta assessment efforts of financial managers, investment analysts, and academic researchers.
Exploring Young Children's Conceptions About Thinking

A growing body of evidence supports the importance of nurturing children's thinking. This article reports on an investigation of the influence of teachers' implementation of the Visible Thinking approach developed within the Harvard Graduate School of Education Project Zero on very young children's concepts of thinking, as measured by the drawing-telling technique. The researchers followed 146 three- to five-year-old children in the classrooms of 10 teachers over a period of 6 months to explore how the children's concepts about thinking developed. The current study first describes the theoretical framework that defines the cluster of concepts related to thinking about thinking (metacognition), social influences on children's concepts of thinking, and cognition and child development. The study is then described, with results showing that the children whose teachers were strong in implementing the Visible Thinking approach advanced their conceptions about thinking after being exposed to the Visible Thinking...
Implementation of active distributed RC anti-aliasing/smoothing filters

The design of an active distributed RC filter is described for use as an anti-aliasing/smoothing filter in a PCM channel bank filter. A new filter configuration (known as a Rauch filter) has been chosen which uses the op amp in inverting configuration with a zero common mode signal and thus results in improved high-frequency attenuation characteristics along with good power supply rejection. A conventional Sallen and Key configuration with distributed RC elements is also discussed.
A Direct Comparison of Right and Left Ventricular Performance in the Isolated Neonatal Pig Heart

A comparison is presented between the performance of the right ventricle (RV) and the left ventricle (LV) in neonatal hearts studied under conditions of volume loading and tachycardia. Isolated, atrially paced (150 or 300 bpm), isovolumically beating pig hearts (1–3 days of age) underwent retrograde aortic perfusion with a nonrecirculating, crystalloid solution. Ventricular pressure was assessed with saline-filled balloon catheters, which allowed separate loading of the RV or LV. Both ventricles showed an initial increase followed by a leveling off, but no decline, in peak systolic pressure (PSP) and +dP/dtmax with volume loading up to an end-diastolic pressure (EDP) of 18 mmHg. The LV generated a higher PSP and +dP/dtmax compared to the RV at equivalent pressure or volume preloads. However, the maximal systolic elastance (Emax) was comparable for both ventricles. Although the RV demonstrated a greater compliance than the LV, the myocardial relaxation time constant (τ) was similar for both chambers at equivalent volume preloads (sarcomere stretch). Positive dP/dtmax correlated closely and in the same linear fashion with −dP/dtmax for both ventricles, indicating that the RV and LV exhibited similar contraction–relaxation coupling. Increasing the heart rate to 300 bpm decreased PSP, +dP/dtmax, and −dP/dtmax and increased EDP for both ventricles, whereas Emax and τ were not significantly altered. Thus, although there are differences between the functional properties of the neonatal RV and LV, there are also important similarities, especially with regard to myocardial relaxation.
Is it Time to Take the Paper Out of Serial Publication

The ramifications of shifting from paper to electronic serial publication are discussed in light of the recent National Institutes of Health (NIH) proposal for a comprehensive electronic archive of peer-reviewed and preprint publications. The paper evaluates six concerns that have been expressed about the conversion to a purely electronic journal system and discusses the economic impact and growing tension among authors, publishers and librarians over scholarly publication.
The maximum response ratio of linear systems

EXCEPT in cases where pure undamped resonances occur, stable linear transmission or filter systems are characterized by bounded response to every bounded input. What is the maximum response amplitude that can be obtained in a linear, time-invariant system subjected to inputs having limited amplitudes? This question may be stated in another way. To what level must the input to a system be limited to insure that the output (or signal level at any given point in the system) does not exceed a given level? This question is of importance in many physical problems.
On the reality of transition state dissociation constants

Transition state dissociation constants are currently considered, utilizing stopped flow equipment. The underlying theory is briefly reviewed, relating the ideas to steady state kinetics of enzyme systems. The ideas are further analyzed under the consideration of chemical relaxation. Test conditions are described which would allow an investigation of the concepts of transition state dissociation constants by chemical relaxation techniques. A discussion concerning the way in which the concepts of transition state dissociation constants relate to other theories which assume short-lived, but real, dissociation constants is included. The theory is rigorously analyzed (in a second part), revealing the nature of the assumption of a transition state dissociation constant: While they may be written in a formal manner, they are not based on reality—on kinetic grounds direct interconversions between transition states are practically impossible. This applies also to transition state dissociation constants involving protons.
Effect of spatial normalization on analysis of functional data

Conventional analysis of functional data often involves a normalization step in which the data are spatially aligned so that a measurement can be made across or between studies. Whether to enhance the signal-to-noise ratio or to detect significant deviations in activation from normal, the method used to register the underlying anatomies clearly impacts the viability of the analysis. Nevertheless, it is common practice to infer only homogeneous transformations, in which all parts of the image volume undergo the same mapping. To detect subtle effects or to extend the analysis to anatomies that exhibit considerable morphological variation, higher dimensional mappings to allow more accurate alignment will be crucial. We describe a Bayesian volumetric warping approach to the normalization problem, which matches local image features between MRI brain volumes, and compares its performance with a standard method (SPM'96) as well as contrast its effect on the analysis of a set of functional MRI studies against that obtained with a 9-parameter affine registration.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Coordinating time-constrained multi-agent resource sharing with fault detection

Sharing common resources in a distributed multi-agent environment requires coordination to avoid faulty system states. The statuses of resources such as personnel, equipments, and environmental factors at a point in time determine the system state at that time. When an agent takes an action at any time point within a scheduled time interval, it becomes a state-transition event occurring at that time. For each event, the underlying state transition relation can be compactly encoded as causal rules, which describe how statuses of resources and environmental factors may change in different ways based on preconditions before the event occurs. The central coordinator needs to check in advance whether any of the possible event sequences consistent with a proposed schedule may end in faulty system states. This fault detection task is NP-complete even for a polynomial-size state space in general. In this paper, we investigate the computational complexity of the fault detection task when agents fairly constrain the maximal length of time intervals. We develop a decomposition algorithm to divide the fault detection task over all events into subtasks involving subsets of the events with overlapping time intervals. For each subtask, only a subspace with reduced dimensionality is involved instead of the whole original state space. When the maximal length of time intervals is constrained below a fair threshold, we prove that with probability approaching one as the size of the problem instance grows the algorithm can accomplish the fault detection task in polynomial time even if the original underlying state space is exponential in size.
Effects of streptozotocin on a clonal isolate of rat insulinoma cells.

Abstract Cytotoxic effects and DNA damage caused by streptozotocin, a potent β-cell toxin and an important chemotherapeutic agent, in an insulin-secreting clonal isolate of a rat insulinoma cell line were evaluated. Cytotoxicity was monitored by phase-contrast microscopy and measurement of insulin release into the culture medium. DNA damage and repair were assessed by changes in nucleoid sedimentation rates. The insulinoma cells were resistant to streptozotocin toxicity as compared to normal rat β-cells. They were also resistant to the stimulatory effects of glucose on insulin release. However, streptozotocin did cause DNA damage that was both dose- and time-dependent. Comparative analysis of streptozotocin-induced DNA damage and that produced by the aglycone N-methyl-N-nitrosourea revealed greater damage with the latter. Thus, streptozotocin, like N-methyl-N-nitrosourea, may enter these cells by passive diffusion rather than selective transport. DNA repair studies indicate that the nicks caused by streptozotocin are sealed and that the DNA is again supercoiled by 14 h. Therefore, overt toxicity may be avoided by a decreased drug uptake compared to normal β-cells and efficient repair mechanisms. These studies suggest that an active glucose-sensing mechanism is necessary to enhance streptozotocin cytotoxicity in both normal and neoplastic β-cells.
The effect of averaging time on oximetry values in the premature infant.

BACKGROUND: The effect of a pulse oximeter9s averaging time on time spent by premature infants in established saturation ranges, as well as on desaturation events, has not previously been reported. OBJECTIVE: Our goal for this pilot study was to evaluate the effect of 2 distinct averaging times on the amount of time spent outside target oxygen saturation (SPo2) as well as the types and durations of desaturation events. METHODS: Neonates RESULTS: The number of desaturations was greater with the 2-second averaging time; however, it did not reach significance when only desaturations of clinically significant duration were included (22.3 vs 19.4 significant events were detected by 2- and 16-second averaging time; P = .1). There was a trend for the longer averaging time to underestimate brief desaturation lasting 300 seconds (40 vs 20 long events). Longer averaging time tended to underestimate desaturation events of greater severity when SPo2 was .05). CONCLUSIONS: These preliminary results suggest that use of longer averaging time reduces the detection of brief periodic desaturation events and of greater severity. It may also interpret a cluster of shorter events as a single, prolonged episode and, thus, potentially overestimate the frequency of long events. The significance of these findings lies in the potential impact on neurodevelopmental outcomes and growth, which will need additional study.
Transient EHL analysis of an elastomeric hydraulic seal

Abstract Recent steady-state numerical analyses of reciprocating hydraulic rod seals have revealed many important details about the operation of such seals, including the fact that they generally operate with mixed lubrication in the sealing interface. However, these seals frequently operate under transient conditions, with the rod speed and sealed pressure undergoing cyclic variations with time. In the present study, a transient numerical model has been developed to take account of the varying rod speed. The model consists of a fluid mechanics analysis of the lubricating film of hydraulic fluid, a contact mechanics analysis of the contacting asperities on the seal lip and a structural analysis of the seal deformations. The fluid mechanics analysis consists of a finite volume solution of the Reynolds equation using a mass-conserving algorithm, which accounts for possible cavitation. The contact mechanics analysis utilizes the Greenwood–Williamson model. The structural analysis consists of a finite element analysis. Typical results are presented for an injection molding application. Of greatest importance is the net leakage per cycle. Also presented are the cyclic histories of such performance characteristics as the lubricating film thickness, contact pressure and fluid pressure distributions, the friction force on the rod and the instantaneous flow rate.
PHOTOINDUCED ELECTRON TRANSFER BETWEEN CYTOCHROME C PEROXIDASE (D37K) AND ZN-SUBSTITUTED CYTOCHROME C : PROBING THE TWO-DOMAIN BINDING AND REACTIVITY OF THE PEROXIDASE

Cytochrome c peroxidase (CcP) binds cytochrome c (Cc) at two distinct surface binding domains, one having high affinity for Cc and the other having low affinity. The identity of the surface binding domains on CcP has been probed by studying photoinduced interprotein heme−heme electron transfer (ET) between Zn-substituted horse Cc, ZnCc, and a cloned cytochrome c peroxidase, CcP(D37K). Charge-reversal substitution of the negatively-charged residue Asp 37 of CcP by a positively-charged residue lysine greatly decreases the stoichiometric constant for 1:1 binding of Cc, from 8.5 × 105 M-1 for the wild-type CcP to 1.2 × 104 M-1 for CcP(D37K) (μ = 18 mM), thereby identifying residue 37 as part of the high-affinity binding domain of CcP(WT) (domain 1). This assignment is consistent with domain 1 as being that observed in a crystal of the Cc−CcP complex. The diminished ability of CcP(D37K) to bind Cc at domain 1 also suppresses binding of a second Cc molecule to form a ternary complex. However, the mutation sharp...
Neuronal plasticity and stressor toxicity during aging.

Abstract Brain aging, Alzheimer disease and stroke share common elements of deficits in calcium regulation, declines in mitochondrial function, increases in generation of reactive oxygen species (ROS), accumulated damage from ROS and immune system dysfunction. The problem is to distinguish less significant side reactions, such as gray hair, from aspects of aging that contribute to disease. Toward establishing cause and effect relationships, a neuron cell culture system is described that allows comparisons with age under uniform environmental conditions. This neuron culture model indicates that susceptibility to death by apoptosis and consequences of the inflammatory response from β-amyloid are age-related and an inherent characteristic of the neurons. Further mechanistic investigations are possible. New therapeutic approaches are suggested that combine inhibition of calcium overloads (calcium channel blockers), reduced ROS damage (melatonin, N -acetyl-cysteine), and bolstered mitochondrial function and energy generation (creatine). Together with newly demonstrated capabilities for adult and aged neuron regeneration and multiplication, i.e. plasticity, these approaches offer new hope toward reversing age-related decrements and damage from neurodegenerative disease.
Self-Assembly and Biphasic Iron-Binding Characteristics of Mms6, A Bacterial Protein That Promotes the Formation of Superparamagnetic Magnetite Nanoparticles of Uniform Size and Shape

Highly ordered mineralized structures created by living organisms are often hierarchical in structure with fundamental structural elements at nanometer scales. Proteins have been found responsible ...
Electronic structure of metal hydrides. III. Photoelectron spectroscopy studies of Sc H 2 , Y H 2 , and Lu H 2

Photoelectron spectroscopy with synchrotron radiation has been used to examine the electronic energy bands of Sc${\mathrm{H}}_{1.85}$, Y${\mathrm{H}}_{1.73}$, and Lu${\mathrm{H}}_{1.77}$ for $15\ensuremath{\le}h\ensuremath{\nu}\ensuremath{\le}100$ eV. The $h\ensuremath{\nu}$-dependent features in the bonding band are discussed in terms of initial-state densities of state and variations in the partial photoionization cross sections. The photoelectron spectroscopy results are combined with those of our earlier optical studies and are used to assess quantitatively the validity of the one-electron band model for $d$-band metal dihydrides. Good overall agreement is found when compared to the results of recent calculations, notably those of Peterman et al., based on the model proposed by Switendick. Band-structure effects are discussed in detail. Emission from the shallow $3p$, $4p$, and $5p$ core levels are revealed through high-photon-energy spectra. Additional features arising from plasmon losses and Auger emission are shown to be important. For Lu${\mathrm{H}}_{2}$, the $4f$ photoionization cross section is determined, and the probability of bulk-plasmon excitations is shown normalized to the $4f$ cross section.
Studies of cholesterol binding in the soluble fraction of the adrenal cortex of the guinea pig

Abstract A cholesterol-binding component has been studied in the supernatant of guinea pig adrenocortical cytosol after heating for two minutes in a boiling water bath. Enzymatic degradation revealed that the binding component was a protein. On sucrose density gradient analysis the cholesterol-binding protein had an S value of approximately 2, and a similar binding component was not present in unheated cytosol. Cholesterol binding to heated adrenal cytosol was unaffected by sulfhydryl reactants. The equilibrium association constant at 0°C was approximately 104 M−1 and the concentration of binding sites was 300 × 10−9 mol per mg protein. Heated adrenal cytosol was found to bind not only cholesterol but also cholesterol sulfate and 20α -hydroxycholesterol when examined by sucrose density gradient analysis. When examined by polyacrylamide gel electrophoresis, it appeared that cholesterol and cholesterol sulfate were bound to the same protein band. On the other hand binding of 20α-hydroxycholesterol was not detected with the multiphasic buffer system that was used. Heated adrenal cytosol did not bind cholesterol oleate, pregnenolone, and pregnenolone sulfate; nor did it bind cyclic AMP, phosphatidyl choline, NADP, acetyl coenzyme A, or prostaglandin E2. Cholesterol binding in heated cytosol was not confined to the adrenal; similar binding was found in liver, kidney, lung, testis, muscle, gut, and brain.
Fiber optic magnetic sensor technology for undersea applications

An array of eight fiber optic vector magnetometers was designed and constructed for use in undersea applications such as harbors, ports, and waterways. We describe the design and performance characteristics of the array including the single-mode fiber optic system and magnetostrictive transducers. Data is presented from both laboratory measurements and from actual undersea operation.
Generation of reactive oxygen species by a persulfide (BnSSH)

Abstract Hydropersulfides (RSxSH) have been implicated as important intermediates in the cell-killing action of the anticancer natural products leinamycin and varacin. It has been suggested that persulfides can mediate the conversion of molecular oxygen to reactive oxygen species ( O 2 - , H2O2, and HO ). Here, experiments with synthetic benzyl hydrodisulfide (BnSSH) provide direct evidence that persulfides readily decompose to produce reactive oxygen species under physiologically relevant conditions.
Examination of grinding techniques for the reuse of by-products of cement production

Abstract The purpose of the letter is to explore an effective way to substantially utilize by-product of cement production by developing an environmentally friendly, sufficiently performing, and cost-effective cementitious product for future concrete materials. The study involves properly blending fly ash with cement kiln dust to create a cementitious material in which the material deficiencies will be converted into benefits. The activation process chosen, in order to facilitate and enhance hydration of the two materials, is mechanical grinding. Properties are determined through the use of heat of hydration test, particle size test and compressive test. The results show that such a material is feasible with additional study.
AWIP: A simulation-based feedback control algorithm for scalable design of self-regulating production control systems

A new simulation-based feedback control algorithm, called Adaptive Work In Process (AWIP), for the design of Self-regulating Production Control Systems (SPCSs) such as Kanban, CONWIP, base stock control and their generalizations is presented. The problem of minimizing average Work In Process (WIP) subject to a required throughput is solved. The AWIP algorithm is used as a feedback controller to adjust the WIP at various stages in the production system. The algorithm is synthesized based on the structural properties of SPCSs that are established analytically in this paper. In this approach simulation is used to provide the feedback to the controllers, and leads to an iterative numerical computational algorithm. Computational experiments show that the AWIP algorithm is near-optimal, and computationally efficient, which makes it an attractive approach for designing and controlling large production systems. [Supplementary materials are available for this article. Go to the publisher's online edition of IIE Tr...
SuperCloud: economical cloud service on multiple vendors

Today, Infrastructure-as-a-Service (IaaS) cloud providers such as Amazon's Elastic Compute Engine (EC2), Google's Compute Engine, and Microsoft's Azure offer elastic and isolated compute resources via virtualization and users often choose one of these providers based on price, locality, performance, and features. Typically, a user will choose the same provider for computation and storage to minimize latency and networking costs. Unfortunately, it can be difficult to switch providers once one is selected due to vendor lock-in [2].
Effects of menthol on peripheral nerve and cortical unit responses to thermal stimulation of the oral cavity in the rat

Neurophysiological responses were recorded in individual fibers of the lingual and chorda tympani nerves and in single cortical neurons in the rat in response to a battery of tactile, thermal and chemical stimuli applied to the oral cavity. Two categories of thermally sensitive units were identified. Chorda tympani fibers and one type of cortical unit ('Type I') were activated by cold water stimulation but were unaffected by warm water or menthol. In contrast, lingual fibers and a different category of cortical units ('Type II') were extremely sensitive to menthol exposure. These units were cold water sensitive, however, this sensitivity was suppressed following menthol presentation.
Comparison checking: an approach to avoid debugging of optimized code

We present a novel approach to avoid the debugging of optimized code through comparison checking. In the technique presented, both the unoptimized and optimized versions of an application program are executed, and computed values are compared to ensure the behaviors of the two versions are the same under the given input. If the values are different, the comparison checker displays where in the application program the differences occurred and what optimizations were involved. The user can utilize this information and a conventional debugger to determine if an error is in the unoptimized code. If the error is in the optimized code, the user can turn off those offending optimizations and leave the other optimizations in place. We implemented our comparison checking scheme, which executes the unoptimized and optimized versions of C programs, and ran experiments that demonstrate the approach is effective and practical.
Quantum interference by femtosecond multi-photon absorption in conjugated dendrimers

We demonstrate high contrast interference fringes when near-IR frequencies co and UV frequency 3ω excite fluorescence via two alternative but in practice indistinguishable quantum pathways. We use specially synthesized organic dendrimers with an exceptionally large three-photon cross section, σ 3 =1.5 10 -79 cm 6 s 2 based on bis-diphenylamino stilbene core and bis-diphenylamino di-styryl benzene repeat units. We show for the first time that quantum interference signal can be strong enough for being observed with an unaided eye.
Serum concentrations across time after subcutaneous administration of liposome‐encapsulated or standard oxymorphone in Rhesus macaques

Our lab has developed a slow-release liposomal formulation of oxymorphone (LEOx). The purpose of this study was to compare serum concentrations of oxymorphone after administration of LEOx and standard oxymorphone (STDOx) to healthy female rhesus macaques. At baseline, 1 mL of blood was drawn from the femoral vein with the animal in a restraint cage. Primates were divided into two groups: (i) LEOx 1.0 mg kg–1(n = 4); 2) STDOx 0.1 mg kg–1(n = 4). Unloaded liposomal vehicle (0.5 mL) was used as a control (n = 2). All treatments were given subcutaneously in a shaved area proximal to the right ileal wing. Femoral venous blood was drawn and serum concentrations of drug were measured at 0.5, 1, 2, 4, 8, 12, 24, 48, 72, 96, and 120 hours. Serum concentrations were measured with ELISA. Serum concentrations were compared between groups and within groups across time with anova. Drug was not detected at any time point in the control group. While sedation was not objectively measured, no animal appeared overly sedate after either treatment. All animals willingly accepted treats and did not appear nauseated or somnolent. Serum concentrations of drug were not significantly different between the two treatment groups from 0 to 2 hours. From 4 hours through 72 hours, however, serum concentrations were significantly higher (p < 0.05) in the animals that received LEOx. By 12 hours, serum concentrations of drug fell below the limit of detection (1.5 ng mL–1) in animals that received STOx. In animals that received LEOx, serum concentrations at 72 hours were comparable to those measured at 4 hours in animals that received STOx. These results suggest that subcutaneous administration of liposomal oxymorphone yields extended serum levels of drug. These results also suggest that liposomal oxymorphone may provide therapeutic (i.e. analgesic) serum concentrations of drug for 2–3 days after a single subcutaneous administration. Further studies are warranted to assess analgesic efficacy and pharmacokinetics of lipsomal oxymorphone in primates.
COMMENTS ON "CAN BAND OFFSETS BE CHANGED CONTROLLABLY?"

Offsets of valence and conduction bands at interfaces are among the key design parameters which allow engineering of electronic properties of semiconductor heterostructures. In this paper are discussed some current theoretical ideas on the causes of the offsets and the extent to which the interface dipole can be changed by atomic scale control of the chemical composition at the interface. The primary conclusion is that significant variations appear possible by the dipoles due to oriented pairs of polar atoms at the interface. Conditions where this can occur are discussed.
On ribosomal gene compensation in Drosophila

Recent studies indicate that genes from only one nucleolus organizer undergo replication during polytenization of salivary gland cells of X/Y flies. This report presents evidence that this is also true X/X polytene cells. Interstrain hybrids were constructed which contain X chromosomes with different rDNA hybridization patterns following digestion with Eco RI, and DNA from diploid or polytene tissue was analyzed using Southern transfers. DNA from diploid tissue of X/X hybrids shows rDNA patterns from both X chromosomes, while DNA from polytene tissue of hybrids shows a pattern characteristic of only one of the X chromosomes. The polytene pattern of the hybrid is independent of whether the dominant X chromosome was derived from the female or male parent. These results suggest that genes from only one nucleolus organizer undergo multiple rounds of replication in X/X polytene cells, and account for the finding that X/O and X/X polytene cells contain similar levels of rDNA without postulating compensation as a ribosomal gene rectification mechanism.
The current status of surgical staging of ovarian serous borderline tumors.

BACKGROUND The purpose of the current study was to evaluate the current practice of surgical staging of ovarian serous borderline tumors. METHODS Women with a diagnosis of ovarian serous borderline tumors whose pathology slides were sent to the M. D. Anderson Cancer Center for second-opinion diagnostic consultation between 1990–1996 were identified. The original pathology reports and M. D. Anderson Cancer Center consultation reports of 255 cases were reviewed for the frequencies of frozen-section analyses and staging biopsies, biopsy results, the specialty of the surgeon, and hospital type. RESULTS The majority (78%) of ovarian borderline tumors primarily were encountered and staged by general obstetrician-gynecologists. Overall, 66% of patients had at least 1 staging biopsy performed. Approximately 12% of subjects underwent complete surgical staging, defined as having biopsy samples taken from pelvic and abdominal peritoneum, omentum, and retroperitoneal lymph nodes. Gynecologic oncologists performed complete staging in 50% of cases, obstetrician-gynecologists performed complete staging in 9% of cases, and general surgeons performed complete staging in 0% cases. The overall frequency of a positive staging biopsy was 37%. Approximately 47% (80 of 169) of patients who underwent biopsies were upstaged as a result of positive biopsies, - with 41% (70 of 169) having extrapelvic spread. CONCLUSIONS Currently, surgical staging for women with ovarian serous borderline tumors remains inadequate, although a significant proportion of patients who undergo staging are noted to have extrapelvic spread. Cancer 1999;85:905–11. © 1999 American Cancer Society.
Hybrid (OpenMP and MPI) parallelization of MFIX: a multiphase CFD code for modeling fluidized beds

We describe the effort and experience in generating a hybrid parallel version of MFIX (Multiphase Flow with Interphase eXchanges), a code for modeling reactive multiphase flow in fluidized beds. The code uses portable OpenMP and MPI in a unified source code. The resulting parallel code has been ported to Beowulf Linux clusters, SGI shared memory multiprocessors, Compaq SC clusters, and an IBM SP. We present hybrid parallel performance results specifically on the 32-way node of IBM SP. This experience is relevant, as most modern high-performance computing (HPC) systems are clusters of SMP nodes.
Near quantum-limited, single-shot coherent arbitrary optical waveform measurements.

Four-quadrature spectral interferometry using balanced coherent detection enables single-shot full-field characterization of complex-shaped optical waveforms with near quantum-limited sensitivity. A 90° optical hybrid places a waveform in four-quadrature-phases with a stronger, well-characterized reference pulse. Measurement of the four spectra with an integrating two-dimensional detector array followed by balanced detection uniquely determines the signal field. Balanced coherent detection provides common-mode noise rejection and coherent gain enabling near quantum-limited sensitivity. The single-shot waveform was temporally gated from a 100 ps periodic train of arbitrary optical waveforms generated using line-by-line pulse shaping on a 10 GHz optical frequency comb. The measurements show arbitrary waveforms with 200-ps record lengths, 500 GHz optical bandwidths and only 1200 detected photons.
Effect of Temperature on Oxygen Consumption of the Leopard Shark, Triakis Semifasciata

The leopard shark, Triakis semifasciata, regularly resides in California's Tomales Bay, which is characterized by thermally different regions ranging from 10°C to 26°C during the summer. Past studies have shown that leopard sharks feed on benthic invertebrate prey similar to that of the sympatric bat ray, Myliobatis californica. Fishes' metabolic (oxygen consumption) rates typically increase with temperature increases, and we measured leopard sharks' metabolic responses and sensitivity to ambient temperature, using flow-through respirometry. Leopard shark oxygen consumption rate increased with increasing temperature, over a range of 12–24°C, with a typical temperature sensitivity (Q10 = 2.51). Whereas bat rays use a highly temperature-sensitive metabolism to efficiently feed (in warmer waters) and digest (in cooler waters) during different phases of the diel cycle, leopard sharks possess a more typical metabolic temperature sensitivity that allows for high-tide foraging, throughout the diel cycle.
Complex and variable crustal and uppermost mantle seismic anisotropy in the western United States

Deformation in the crust and mantle — measured using seismic anisotropy — is poorly constrained in the western United States because of inconsistencies in the existing data. A three-dimensional model that reconciles these discrepancies reveals that seismic anisotropy in the crust correlates with different geological provinces, but is unrelated to anisotropy in the underlying mantle.
Markov Decision Processes formulation for stochastic and dynamic bank branches location problems

The optimization of investment policies in bank branches within dynamic and stochastic economic environment has become more and more important nowadays. However, it has not been generally formulated due to the randomness in markets and the complicated dynamics of economic growth. This paper formulates the stochastic and dynamic bank branches location problem as a Markov Decision Processes (MDP), and presents a policy iteration algorithm to obtain the optimal investment policies. Numerical examples demonstrate the effectiveness and efficiency of our formulation and algorithm. Furthermore, the formulation and algorithms have been embedded into an IBM asset called IFAO-SIMO, and they have been acting as the mathematical kernels of the asset optimization engine.