cssi/SciSciGPT-SciSciNet huggingface dataset:
Polonium-Lead Extractions to Determine the Best Method for the Quantification of Clean Lead Used in Low-Background Radiation Detectors

Radiation detectors used to search for the existence of exceptionally rare phenomena, such as double-beta decay and dark matter interactions, as well as tiny traces of environmental radioactivity, require the elimination of background signals. Modern detection systems created from ultra pure materials and operated deep underground may be sensitive enough to “see” these rare phenomena, but background activity in Pb gamma-ray shielding could still be a critical stumbling block owing to alpha and beta emissions of Pb, Bi, and Po in the mass 210 chain. To minimize the probability of overwhelming activity from Pb, the alpha activity of 210Pb is quantified. However, a reliable quantification procedure that does not require large volumes of chemicals has not yet been established. Two procedures created for this purpose have been tested for the quantification of alpha activity in lead. Both procedures were designed to start with less than 10 g Pb samples to reduce reagents needed and combined precipitation with column separation to isolate 210Pb, followed by alpha spectrometry. One procedure shows promise for obtaining high recoveries and good separation.
Design with FinFETs: design rules, patterns, and variability

FinFETs have proven to be the device of choice for the next few technology generations. Consequently, design rules and limitations related to FinFETs need to be carefully understood. We present restricted and gridded design rules related to FinFETs. We also present results which indicate that a complete front-end-of-line (FEOL) and middle-of-line (MOL) of a memory with controllers can be designed from a fixed set of patterns. We also indicate sources of variations in FinFETs.
THE USE OF SPECIFIC ANTIBODY IN ELECTRON MICROSCOPY III. Localization of Antigens by the Use of Unmodified Antibody

Antibody staining was observed in the electron microscope by means of untagged antibody and osmium fixation. The antibody was visualized as a change in morphology due to its deposition on the antigenic structures. Glycerinated chicken breast muscle was stained with antimyosin, anti-H-meromyosin, and antiactin. The staining patterns obtained by electron microscopy were consistent with those previously demonstrated by fluorescence microscopy. A second method was used for confirmation of antibody staining. This consisted of extraction of unstained portions of the sarcomere with 0.6 M potassium iodide, 10-4 M adenosine triphosphate solution. Stained regions of the sarcomere remained intact because of insolubility of the combined antigen and antibody.
Consistent subdivision of convex polyhedra into tetrahedra

This paper presents a simple method of subdividing a grid of convex polyhedral cells into tetrahedra such that the subdivisions of two adjacent cells divide their common face into the same set of triangles. The method is then generalized to grids of convex polytopes in n dimensions.
Feline leukemia virus integrase and capsid packaging functions do not change the insertion profile of standard Moloney retroviral vectors

Feline leukemia virus integrase and capsid packaging functions do not change the insertion profile of standard Moloney retroviral vectors
Multimedia transport of particle-bound organics: Benzo(a)Pyrene test case

Abstract A screening multimedia-compartmental (MCM) modeling approach is presented for predicting the distribution of particle-bound pollutants within an environment consisting of the atmosphere, surface water, and surface soil compartments. An MCM model was used to simulate the dynamic distribution of Benzo(a)Pyrene (B(a)P) for a study region located in southeast Ohio. The model incorporates theoretical estimates of the dry deposition velocity and a new semi-empirical model for rain scavenging of B(a)P. The predicted concentrations of B(a)P compared favorably with available field data.
Rapid volume expansion in the Torpedo electric organ associated with its postsynaptic potential.

By electrically stimulatingTorpedoelectric organs enclosed in a sealed plastic chamber, it was demonstrated that the production of a postsynaptic potential is accompanied by a rapid increase in the volume of the organ. This increase started almost simultaneously with the onset of the postsynaptic potential and reached its maximum at about the end of the potential. The volume returned slowly to its resting level. Repetitive stimulation produced a summation of volume changes. The maximum change evoked by a single electric shock was roughly 10−6times the electrocyte volume. The thermal expansion of the organ associated with the production of a postsynaptic potential accounts for roughly 25% or less of this volume increase. The possibility is pointed out that a cation-exchange process involving Ca2+on anionic sites in the electrocyte protoplasm may be at the base of the volume changes.
Testing whether F is “more IFRA than is G”

Abstract For testing the null hypothesis that two life distributions F and G are equal versus the alternative hypothesis that F is more increasing failure rate average than is G, a class of tests is proposed. The properties of tests in this class such as unbiasedness, consistency and asymptotic normality are established. Monte Carlo estimates of power are obtained for small sample sizes. The asymptotic relative efficiency of tests in the class with respect to Hollander, Park and Proschan's (1986) test is shown to be reasonably high.
Improvements in modeling sagebrush concentrations of radioiodine released from the Hanford site.

Abstract The Hanford Environmental Dose Reconstruction Project estimated the radiation dose to individuals from historical emissions of radioactive materials from the Hanford Site in Washington State. Project validation studies using predicted activity concentrations of 131 I on sagebrush ( Artemisia tridentata ) showed a systematic underestimation against historical data during cold weather months, indicating a need for sagebrush model improvement. A deposition model for semi-volatile organic materials presented by Komp and McLachlen ( Environ. Sci. Tech. 31 (1997) 886–890) is adapted here for gaseous iodine onto sagebrush. The deposition model includes a temperature-dependent term based on an integrated van’t Hoff equation. Calibration data for the model are obtained from a release of 131 I in 1963. Modeling results for releases in 1946 show a good match between historical data and predicted results using the new model. The new model shows improvement over interception–fraction type models, but requires plant-type-specific calibration data.
Negative index and indefinite media waveguide couplers

We study the coupling interaction between dielectric waveguides and coupling elements made from negative-refracting media. The coupling configuration consists of a length of dielectric waveguide, which terminates either directly into or near a planar layer composed of the negative-refracting medium, and is followed by a second waveguide. Radiation output from the first waveguide is refocused at the position of the second waveguide, so that the negative-refracting layer serves as a coupler between the waveguides. Because both isotropic negative-index layers and bilayers of indefinite media can recover the near-field, evanescent components of a source field distribution, the coupling between the input and output waveguides can be highly efficient – in principle providing perfect, lossless coupling. We present simulations and some initial experimental results illustrating the coupling effect, and speculate on the potential for optical fiber couplers and integrated modulators.
Robust stabilization of singularly perturbed systems

Abstract We discuss the problem of designing stabilizing controllers for singularly perturbed systems on the basis of simplified models. In [1], it was shown that a constant gain output feedback controller designed on the basis of the simplified model need not stabilize the ‘true’ system containing both fast and slow modes. This phenomenon was then expanded to include the case where the simplified system is strictly proper in [2]. The objectives of this note are threefold: (i) to show that, given any proper system and any stabilizing controller for it that is proper but not strictly proper, there exists a singular perturbation of the system that is destabilized by that controller, (ii) to show that any strictly proper controller for a singularly perturbed system designed on the basis of a reduced order model will stabilize the true system for sufficiently small values of the fast dynamics parameter, and (iii) to provide a characterization, in the same spirit as [3,4], of the set of all strictly proper controllers that stabilize a given proper plant. By combining these results, it is possible to generate the class of all robustly stabilizing controllers for a given singularly perturbed system.
Eustatic and tectonic control on the distribution of marine seismites: examples from the Upper Ordovician of Kentucky, USA

Abstract Widespread zones of soft-sediment deformation are not ubiquitous throughout the rock record. Rather, they are associated with orogenic sediments and are concentrated in specific portions of depositional sequences characterized by deformation prone facies. Upper Ordovician soft-sediment deformation features exposed in Kentucky are here interpreted as the result of seismically induced thixotropic fluidization of muds resulting in foundering of denser silts and carbonate sands and corresponding diapiric injection of muds. Severity of soft-sediment deformation is associated with sediment density gradients, bed thicknesses, and varying magnitudes of triggering events. The widespread nature (>5000 km 2 ) of multiple deformation horizons argues for a seismic trigger resulting from reactivation of multiple basement faults. Eight large-scale (3rd order) depositional sequences were examined for the presence of specific deformation features and stratigraphic position of those intervals. The regular distribution of deformation prone facies throughout the Upper Ordovician seems to have been regulated by eustatic fluctuations. Seismicity generated by far-field tectonics provided the triggering mechanism to disrupt deformation prone strata. The record of seismites and their co-occurrence with K-bentonites provides a meter of intensity and timing of tectophases of the Taconic Orogeny.
Lightweight checkpointing for concurrent ml

Transient faults that arise in large-scale software systems can often be repaired by reexecuting the code in which they occur. Ascribing a meaningful semantics for safe reexecution in multithreaded code is not obvious, however. For a thread to reexecute correctly a region of code, it must ensure that all other threads that have witnessed its unwanted effects within that region are also reverted to a meaningful earlier state. If not done properly, data inconsistencies and other undesirable behavior might result. However, automatically determining what constitutes a consistent global checkpoint is not straightforward because thread interactions are a dynamic property of the program. In this paper, we present a safe and efficient checkpointing mechanism for Concurrent ML (CML) that can be used to recover from transient faults. We introduce a new linguistic abstraction, called stabilizers, that permits the specification of per-thread monitors and the restoration of globally consistent checkpoints. Safe global states are computed through lightweight monitoring of communication events among threads (e.g., message-passing operations or updates to shared variables). We present a formal characterization of its design, and provide a detailed description of its implementation within MLton, a whole-program optimizing compiler for Standard ML. Our experimental results on microbenchmarks as well as several realistic, multithreaded, server-style CML applications, including a web server and a windowing toolkit, show that the overheads to use stabilizers are small, and lead us to conclude that they are a viable mechanism for defining safe checkpoints in concurrent functional programs.
Prediction of interstitial gas pressure in multilayer insulation during rapid evacuation

Gas pressure differential across multilayer insulation blanket during rapid evacuation predicted, using one dimensional flow theory
Phosphorylation of Isocitrate dehydrogenase of Escherichia coli

Addition of acetate to a stationary phase culture of Escherichia coli in glycerol mineral salts medium containing phosphorus-32-labeled orthophosphate results in rapid loss of isocitrate dehydrogenase activity and concomitant incorporation of phosphorus-32 into the enzyme. This is the first example of protein phosphorylation in a bacterium in which the endogenous substrate for the protein kinase has been identified.
2009 Special Issue: Optimal control of unknown affine nonlinear discrete-time systems using offline-trained neural networks with proof of convergence

The optimal control of linear systems accompanied by quadratic cost functions can be achieved by solving the well-known Riccati equation. However, the optimal control of nonlinear discrete-time systems is a much more challenging task that often requires solving the nonlinear Hamilton-Jacobi-Bellman (HJB) equation. In the recent literature, discrete-time approximate dynamic programming (ADP) techniques have been widely used to determine the optimal or near optimal control policies for affine nonlinear discrete-time systems. However, an inherent assumption of ADP requires the value of the controlled system one step ahead and at least partial knowledge of the system dynamics to be known. In this work, the need of the partial knowledge of the nonlinear system dynamics is relaxed in the development of a novel approach to ADP using a two part process: online system identification and offline optimal control training. First, in the system identification process, a neural network (NN) is tuned online using novel tuning laws to learn the complete plant dynamics so that a local asymptotic stability of the identification error can be shown. Then, using only the learned NN system model, offline ADP is attempted resulting in a novel optimal control law. The proposed scheme does not require explicit knowledge of the system dynamics as only the learned NN model is needed. The proof of convergence is demonstrated. Simulation results verify theoretical conjecture.
Summary of nonaxisymmetric nozzle internal performance from the NASA Langley Static Test Facility

Early experimental work on multifunction nozzles (prior to 1978) concentrated on quantifying the isolated and installed performance of specific nozzle designs at various power settings during cruise, vectored thrust, and reverse thrust operating modes. Since 1978, however, significant effort has been expended on developing a parametric data base on nozzle internal design variables which could lead to improved internal performance and/or lower structural weight. Much of this work has been conducted in the Static Test Facility of the NASA/Langley 16-Foot Transonic Tunnel using subscale models and high pressure air to simulate jet exhaust. A review of the research effort on nonaxisymmetric multifunction nozzles along with a summary of many of the results is presented. In addition, internal performance results from subscale models tested in the Static Test Facility and from full-scale engine/nozzle tests are compared.
Predicting Minimum Carbon Usage for PAC Adsorption of Trace Organic Contaminants from Natural Water

Powdered activated carbon (PAC) is an excellent adsorbent for drinking water treatment of many trace organic contaminants. To evaluate and design a PAC adsorption process for a particular application, it is necessary to know the minimum (lowest economical) carbon (adsorbent) usage (MCU) defined thermodynamically. In this work, an explicit relationship is developed for predicting the MCU required for a desirable level of treatment of a target trace organic compound (TC). The adsorption processes considered are PAC slurry contactors idealized either as batch reactors, plug flow reactors, or continuous-flow stirred tank reactors. Comparing with the ones previously available in the literature, this newly developed relationship, as a predictive tool for practical uses as well, is more accurate because it does not need to assume that the MCU required for target TC removal can always reduce the competing background natural organic matter (NOM) to a level much less than the NOM initial/influent concentration. Applications of the relationship developed herein to PAC adsorption of typical trace organic contaminants in natural water are demonstrated with isotherm data from multiple literature sources.
Hyperdispersion grating arrangements for compact pulse compressors and expanders

A novel, but general, arrangement of parallel sets of gratings is presented that can effectively increase the dispersion of pulse compressors and expanders by over an order of magnitude. These arrangements will dramatically reduce the footprint of the pulse compressors and expanders used in CPA.
The moderating effect of private self-consciousness on the stability of vocational interests

Abstract This study investigated the potential moderating effect of private self-consciousness on the stability of vocational interest inventory scores and profiles. We hypothesized that participants higher in private self-consciousness would have more stable interest scores and profiles on the Self-Directed Search (SDS; Holland, Fritzsche, & Powell, 1994 ) across a 12-week time interval than would participants lower in private self-consciousness. Results revealed that private self-consciousness did moderate the stability of SDS Enterprising interest scores. Contrary to our hypothesis, private self-consciousness did not moderate the stability of the other five SDS interest scores or SDS interest profile stability.
Heat transfer analysis of thermo-active foundations

Abstract A transient, three-dimensional finite volume method (FVM) numerical model was developed specifically for the purpose of modeling thermo-active foundations. Validation against a physical experiment was first carried out using measurements obtained from an experimental set-up of a thermo-active foundation. The model was then used to investigate three design parameters as they apply to thermo-active foundations including tube spacing, pier depth, and flow velocity. The model was also used to investigate the thermal interaction between the thermo-active foundation and the building above it using annual simulations based on hourly weather data for Boulder, CO. In particular, it is found that thermo-active foundation can increase a building's ground-coupled slab heat loss for 57% of hours during the heating season when compared to a standard foundation. A decrease in slab heat loss or increase in slab heat gain was seen for 32% of hours during the cooling season.
Compact electro-optic imaging Fourier transform spectrometer

JPL is developing an innovative compact, low mass, Electro-Optic Imaging Fourier Transform Spectrometer (E-O IFTS) for hyperspectral imaging applications. The spectral region of this spectrometer will be 1 - 2.5 μm (1000 - 4000 cm -1 ) to allow high-resolution, high-speed hyperspectral imaging applications. The specific applications for NASA's missions will focus on the measurement of a large number of different atmospheric gases simultaneously in the same airmass. Due to the use of a combination of birefringent phase retarders and multiple achromatic phase switches to achieve phase delay, this spectrometer is capable of hyperspectral measurements similar to that of the conventional Fourier transform spectrometer but without any moving parts. In this paper, the principle of operations, system architecture and recent experimental progress will be presented.
Measuring fab overlay programs

This paper presents a methodology for measuring and improving the effectiveness of stepper overlay management on product wafers in the semiconductor industry. The research that supports this measurement approach encompasses over 12 fabs with over 30 technologies. Overlay performance, stepper deployment, stepper productivity and die yield loss due to overlay error were studied. To provide an objective measurement of a fab overlay methodology and performance, measurements were made of the overall overlay design rule compliance and distribution and of the overlay variance and distribution by stepper field location. Modeled data analysis was used to assess and validate the effectiveness of the stepper control methodology, sampling level and field/target locations. Balancing stepper productivity and overlay results is a problem in most fabs. An overlay 'opportunity box' is defined that allows a fab to explore overlay error ranges, lost stepper productivity, and product overlay design rule requirement by stepper deployment. Stepper deployment decision tend to be digital - 'engineering' or 'manufacturing' - quantification of die yield loss as a function of overlay error is usually required to make deployment changes. Several examples of die yield loss, as a function of overlay error and distribution, are presented. A brief introduction of the yield analysis technique used is provided.
Continuous finite elements in space and time for the nonhomogeneous wave equation

Finite element approximation, in space and time, for the wave equation with a forcing term is considered. The rates of convergence, in H1 × L2 and L2 × H−1 topology, reconstructing the “best” approximation properties of the subspaces are derived.
Comparing the Effectiveness of an Inverted Classroom to a Traditional Classroom in an Upper-Division Engineering Course

An inverted, or flipped, classroom, where content delivery includes video lectures watched outside of the classroom, is a method that can free classroom time for learner-centered activities such as active and problem-based learning. This study compared the effectiveness of an inverted classroom to a traditional classroom in three areas: 1) content coverage; 2) student performance on traditional quizzes and exam problems; and 3) student observations and perception of the inverted classroom format. A control-treatment experiment comparing an inverted classroom to a traditional lecture-style format was used. The results show that: 1) the inverted classroom allowed the instructor to cover more material; 2) students participating in the inverted classroom performed as well or better on comparable quiz and exam questions and on open-ended design problems; and 3) while students initially struggled with the new format, they adapted quickly and found the inverted classroom format to be satisfactory and effective.
A 32P-postlabeling method for the detection of adducts in the DNA of human fibroblasts exposed to sulfur mustard

Abstract Since the toxicities of sulfur mustard are attributed to DNA alkylation, levels of DNA modification in exposed cells should correlate with the intensity of exposure. We have found that 32 P-postlabeling can be used successfully to detect the major adduct, 7-hydroxyethylthioethyldeoxyguanosine 5'-phosphate (HETEpdG), that is formed in DNA by sulfur mustard. This method has been used to establish a correlation between exposure and adduct formation in human fibroblasts grown in cell culture and exposed to sulfur mustard concentrations between 2.5 and 15 μM. DNA was recovered from these cells using a salt precipitation method to remove proteins and was found to have an HETEpdG content which increased linearly with SM concentration. This relationship shows that one HETEpdG per 10 6 nucleotides is produced at a SM concentration of 2.3 μM. Growth of fibroblast cells, assayed by trypan-blue exclusion, is somewhat inhibited by 2 μM SM, indicating that 32 P-postlabeling has the requisite sensitivity to detect adducts at levels of SM that are minimally toxic.
Treatment of unilateral coronal synostosis by endoscopic strip craniectomy or fronto-orbital advancement: Ophthalmologic findings.

Background Unilateral coronal synostosis results in ipsilateral retrusion of the forehead and superior orbital rim, shortening the elevation of the orbital roof and contralateral frontal bossing and orbital roof depression. This craniosynostosis is associated with the development of V-pattern strabismus and aniso-astigmatism. Since 2004 endoscopic strip craniectomy performed in patients by 3 months of age has been offered as an alternative to fronto-orbital advancement at 9 to 11 months of age. We compare the incidence and severity of V-pattern strabismus and aniso-astigmatism in children treated by these 2 procedures. Methods A retrospective review identified 37 children with unilateral coronal synostosis treated with either fronto-orbital advancement or endoscopic strip craniectomy. Incidence and severity of V-pattern strabismus, fundus excyclotorsion, and aniso-astigmatism was recorded for an "early" examination (between 2 and 14 months of age) and a "late" examination (between 14 and 45 months of age). Results Early examination revealed no statistical difference in severity of V-pattern strabismus or aniso-astigmatism between the 2 groups. At late examination there was a trend toward greater severity of V-pattern strabismus, an increase in excyclotorsion, and a statistically significant increase in the standard deviation of aniso-astigmatism in the cohort of children treated by fronto-orbital advancement. Conclusions Children with unilateral coronal synostosis treated by early endoscopic strip craniectomy may develop less severe V-pattern strabismus, excyclotorsion, and range of aniso-astigmatism than those treated by later fronto-orbital advancement. This is an early, retrospective, nonrandomized study with a short follow-up period; longer follow-up is necessary to confirm these results.
Postirradiation creatinuria in Macaca mulatta.

SummaryFour adult male Macaca mulatta, monkeys weighing an average of about 10 lb were placed on a creatine-free diet for 7 to 9 days. After the urinary level of creatine excretion had reached a plateau, the animals were irradiated with 1,000 rep of X-rays. A creatinuria of approximately 4 times normal was excreted over the first 4 days in a pattern similar to that previously found in the rat.
Visual-Vestibular Interactions During Vestibular Compensation: Role of the Pretectal NOT in Horizontal VOR Recovery After Hemilabyrinthectomy in Rhesus Monkey

Damage to the vestibular labyrinth leads to profound nystagmus and vertigo. Over time, the vestibular-ocular system recovers in a process called vestibular compensation leading to reduced nystagmus...
Comment on “Experimental Test of Self-Shielding in Vacuum Ultraviolet Photodissociation of CO”

Chakraborty et al. (Reports, 5 September 2008, p. 1328) suggested that experimental results provide support for CO photodissociation having caused the oxygen isotope ratio associated with the early solar nebula. We point out that further analysis is required before other mechanisms, such as self-shielding, are shown to be of little importance.
Two-dimensional curvature operators

Most computer vision systems use one-dimensional operators to calculate the curvature of boundaries or image contours. However, the more sophisticated biological systems use two-dimensional operators. Here we analyze how curvature can be computed by using two-dimensional operators and show the relation of this approach to the one-dimensional methods currently in use.
Improvement of an Extrapolation Scheme for Strong-Coupling Expansion in Quantum Field Theory

By letting the lattice spacing $a$ approach zero as the order $n$ of perturbation theory increases in such a way that the product $\mathrm{na}$ remains fixed, we substantially improve the numerical predictions. The approximation scheme described here is superior to conventional Pad\'e approximation.
Component-based handprint segmentation using adaptive writing style model

Building upon the utility of connected components, NIST has designed a new character segmentor based on statistically modeling the style of a person's handwriting. Simple spatial features capture the characteristics of a particular writer's style of handprint, enabling the new method to maintain a traditional character-level segmentation philosophy without the integration of recognition or the use of oversegmentation and linguistic postprocessing. Estimates for stroke width and character height are used to compute aspect ratio and standard stroke count features that adapt to the writer's style at the field level. The new method has been developed with a predetermined set of fuzzy rules making the segmentor much less fragile and much more adaptive, and the new method successfully reconstructs fragmented characters as well as splits touching characters. The new segmentor was integrated into the NIST public domain form-based handprint recognition systems and then tested on a set of 490 handwriting sample forms found in NIST special database 19. When compared to a simple component-based segmentor, the new adaptable method improved the overall recognition of handprinted digits by 3.4 percent and field level recognition by 6.9 percent, while effectively reducing deletion errors by 82 percent. The same program code and set of parameters successfully segments sequences of uppercase and lowercase characters without any context-based tuning. While not as dramatic as digits, the recognition of uppercase and lowercase characters improved by 1.7 percent and 1.3 percent respectively. The segmentor maintains a relatively straight-forward and logical process flow avoiding convolutions of encoded exceptions as is common in expert systems. As a result, the new segmentor operates very efficiently, and throughput as high as 362 characters per second can be achieved. Letters and numbers are constructed from a predetermined configuration of a relatively small number of strokes. Results in this paper show that capitalizing on this knowledge through the use of simple adaptable features can significantly improve segmentation, whereas recognition-based and oversegmentation methods fail to take advantage of these intrinsic qualities of handprinted characters.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Ballistic electron emission microscopy measurements of epitaxially grown Pt/CaF2/Si(111) structures

The electronic transport properties and surface morphology of ultrathin Pt/CaF 2 /Si(111) metal-insulator-semiconductor structures have been characterized in-situ by ballistic electron emission microscopy (BEEM) and scanning tunneling microscopy (STM). Platinum thicknesses from 2-53 A and CaF 2 thicknesses of 5 and 15 A have been characterized. The STM images of the Pt/CaF 2 /Si(111) structures show the atomic steps of the underlying CaF 2 morphology, as well as the formation of Pt nodules. The BEEM spectra from the thicker Pt coverages show an onset near the conduction band minimum (CBM) of the CaF 2 . The BEEM spectra from the thinner Pt coverages show an additional peak near 2 eV, which has not been observed in previous studies of metal/CaF 2 /Si(111) structures. This extra peak has been attributed to quantum mechanical resonant tunneling through the ultrathin MIS structure.
On the apparent phosphatase activity of tobacco mosaic and bushy stunt viruses

Purified preparations of tobacco mosaic and tomato bushy stunt viruses have been found to possess no phosphatase activity towards disodium phenyl phosphate. However, the juice of Turkish tobacco plants was found to possess phosphatase activity; hence, incompletely purified virus preparations may show phosphatase activity due to incomplete removal of the phosphatase present in the starting material.
Phasic distribution of seminiferous tubules in rats treated with triphenyltin compounds

Reports concerning the effects of triphenyltin compounds on animal reproductive tissue are numerous. Triphenyltins have been used for reproductive control of the German cockroach Blatella sermanica (L.), the confused flour beetle Tribolium confusum Jacquelin du Val, and the house fly Musca domestica L. (KENAGA 1965). Triphenyltin acetate (TPTA) and triphenyltin chloride (TPTC) specifically have been shown to be house fly chemosterilants by other investigators (FYE et al 1966; KISSAM & HAYS 1966). NEWTON & HAYS (1968) reported that treatment of female albino rats (42-46 days old) at a dosage of 20 mg/kg/day produced marked effects on ovarian tissue after only 5 days of treatment. Among these effects were a decreased number of mature follicles, an increased incidence of atresia in early follicle development and a pronounced decrease in the number of corpora lutea present. TNis latter effect indicated a decreased ovulation, thus a decreased fertility. Other studies revealed a decreased spermatogenesis in 35-40 days old albino rats treated for 19 days with TPTA and TPTC at a dosage of 20 mg/kg/day (PATE & HAYS 1968).
Critical Role of the Linking Amide in CC-1065 and the Duocarmycins: Implications on the Source of DNA Alkylation Catalysis

The preparation and evaluation of both enantiomers of 5 are described and it constitutes an analogue of CBI-TMI (4), the duocarmycins, and CC-1065 in which the amide linking the alkylation and DNA ...
Flow properties of high‐molecular‐weight DNA solutions: Viscosity, recoil, and longest retardation time

Viscosity η, recoil Γ, and longest retardation time τ1R were measured for buffered aqueous solution of T2 DNA (M = 1.3 × 108) and cell lysattes of Bacillus subtiles W23 (DNA M = 2 × 109) as a function of concetration, shear stress σ, and time of shear t, using a cartesian-diver-suspended couette flow system. For the T2 solution, η decreased with increasing σ, Γ(t) going through a maximum with t. For the B. subtiles lysates, the preponderant rheological component of which is chromatin DNA, above a critical σ, the η, Γ(t), and τ1R increased t over 15 to 45 minutes duration to values up to several times larger, indicating the formation of intermolecular aggregates. The onset of such effects and their significance in th e measurement of molecular properties by hydrodynamic means is disscussed.
"Someone with Like a Life Wrote It": The Effects of a Visible Author on High School History Students.

This study investigated the effects of a visible author (one who writes in the 1st person, revealing personal opinions and self) on adolescents reading history textbooks. Six high school sophomores read a passage from a textbook that featured an anonymous author (one who writes in the 3rd person, revealing little about personal opinions and self) and a similar text featuring a visible author. Data from think-aloud protocols and semi-structured interviews were analyzed to understand the impact of these authors on students' construction of historical knowledge and on their attitudes toward the texts and toward the discipline as a whole. Students interacted frequently with the visible author, engaging in mental conversations. These conversations led students to a closer relationship with the information presented in the text. The nature of these relationships, both for the visible text and the anonymous text, is discussed.
Dynamic modeling of environmental amenity-driven migration with ecological feedbacks.

Abstract Environmental amenity-driven migration presents a double-edged sword to policy makers concerned with both economic and ecological sustainability. Clearly the protection of environmental amenities is important, but what is the right balance between ecosystem protection and regional economic processes that simultaneously respond to and degrade ecological resources? We consider this question in the context of households that are attracted to a region by urban and lake amenities and a lake ecosystem that becomes degraded by land development. An analytical expression for the time evolution of population is derived from households' and firms' optimizing behaviors. Numerical methods with phase plane diagrams are used to study the steady state and transient dynamics of the resulting population-phosphorus coupled system. The system is found to be bi-stable under a range of parameter values with one attractor corresponding to a desired “balanced” economy-ecology state and the other to a very small population base with fully restored ecology. We examine the dynamics and quantify the resilience of the system in and away from the balanced steady state using phase plane diagrams that demarcate the two domains of attraction. Economic-ecological interactions fundamentally alter regional economic dynamics and influence the resilience of the balanced domain of attraction. For example, a one percent increase in the loadings coefficient associated with residential land development generates a three percent decline in the resilience of the balanced state. We find that economic feedbacks often increase system resilience. Initial increases in the attraction of urban amenities spur greater population growth that increases the resilience of the balanced state. In addition, price feedbacks that arise from capitalized (dis)amenities increase the resilience of the system to bad ecological shocks.
Albumin-like proteins are critical regulators of vascular redox signaling.

This laboratory previously identified an albumin-like protein (denoted as p70) as a component of the macromolecular complex assembled within the 5′-regulatory region of redox-sensitive genes in vascular smooth muscle cells (vSMCs). Here we show that p70 is present in the cytosolic and nuclear compartments of vSMCs and dynamically responsive to redox status. Intense cytoplasmic and perinuclear staining, coupled with enhanced nuclear localization, was observed in vSMCs, but not HepG2 cells, treated with benzo(a)pyrene (BaP), H2O2, or N-acetylcysteine, agents known to modulate redox status. 3′ RACE indicated that p70 is not generated as a product of endogenous gene expression, but rather taken up from the extracellular compartment. While p70 was undetectable in cells grown for 24 hours under serum-free conditions, cell-associated, acid-resistant albumin was detected 30 min after the addition of exogenous albumin. vSMCs incubated at 4°C with 100 μg/mL unlabeled BSA and 10 μg/mL FITC-BSA for 60 minutes and switched to 37°C to examine temperature-sensitive label uptake showed punctate structures throughout the cell consistent with albumin internalization at the higher temperature. Albumin was found to influence redox-signaling, as evidenced by modulation of cyp1a1 gsta1 and Ha-ras gene inducibility. Together, these results implicate albumin and albumin-like proteins as critical regulators of vascular redox signaling.
Effect of cholesterol crystals on plaques and intima in arteries of patients with acute coronary and cerebrovascular syndromes.

Plaque disruption (PD) causes most acute cardiovascular events. Although cholesterol crystals (CCs) have been observed in plaques, their role in PD was unknown. However, cholesterol expands with crystallization tearing and perforating fibrous tissues. This study tested the hypothesis that CCs can damage plaques and intima, triggering PD, as observed in tissues prepared without ethanol solvents that dissolve CCs. Coronary arteries of patients who died of acute coronary syndrome (n = 19) and non–acute coronary syndrome causes (n = 12) and carotid plaques from patients with (n = 51) and without (n = 19) neurologic symptoms were studied. Samples were examined for CCs perforating the intima using light and scanning electron microscopy (SEM) with ethanol or vacuum dehydration. In addition, fresh unfixed carotid plaques were examined at 37°C using confocal microscopy. Crystal content using SEM was scored from 0 to +3. SEM using vacuum dehydration had significantly higher crystal content compared with SEM using ethanol dehydration (+2.5 ± 0.53 vs +0.25 ± 0.46; p
RELEVANCE OF VASCULAR STRUCTURAL AND SMOOTH MUSCLE SENSITIVITY CHANGES IN HYPERTENSION

Summary This is a mini-review of the vascular changes that occur in experimental hypertension. Augmented vascular resistance and reactivity appear to be due to an increase both in wall thickness and in vascular smooth muscle sensitivity. The increase in wall thickness is an adaptive change that is secondary to the increase in arterial pressure; the altered smooth muscle sensitivity occurs in the absence of an increase in arterial pressure and hence may initiate the increase in vascular resistance and reactivity of experimental hypertension. Studies of subcellular function indicate that changes in smooth muscle sensitivity may be caused by an increase in cell membrane permeability and an altered handling of calcium by its subcellular sequestering system. This review was supported by U.S. Public Health Service grant HL-03756 from the National Heart and Lung Institute. K.H. Berecek is a predoctoral fellow supported by NIH grant PHS-4620.
Squamous cells in the maternal pulmonary circulation

Identification of squamous cells in the maternal pulmonary arterial circulation, either at autopsy or in blood aspirated from a pulmonary artery catheter, is currently regarded as pathognomonic for amniotic fluid embolism. Sixteen pregnant women underwent pulmonary arterial catheterization for a variety of medical indications. Examination of the buffy coat fraction of the distal lumen aspirate resulted in the identification of squamous cells in all cases. Squamous cells were similarly identified in control specimens from 17 nonpregnant patients; however, the difference in cell count between the pregnant and nonpregnant patients was significant. Such cells presumably reflect, in part, bloodstream contamination from sites of venous access. Reliable differentiation of adult from fetal squamous cells is not possible; however, the significant increase in cell count documented in pregnant patients suggests a possible fetal origin for some squamous cells detected during pregnancy. The detection of squamous cells in the pulmonary arterial circulation of pregnant women is not pathognomonic for amniotic fluid embolism. In a critically ill obstetric patient, such a finding should not deter the clinician from a thorough search for other causes of hemodynamic instability.
Comparison of the rate of excision of major UV photoproducts in the strands of the human HPRT gene of normal and xeroderma pigmentosum variant cells

Xeroderma pigmentosum (XP) variant patients are genetically predisposed to sunlight-induced skin cancer. Fibroblasts from such patients are extremely sensitive to mutations induced by UV radiation, and the spectrum of mutations induced in their hypoxanthine phosphoribosyltransferase (HPRT) gene differs significantly from that seen in normal cells. To determine if this UV hypermutability reflects abnormally slow excision repair of cyclobutane pyrimidine dimers (CPD) or 6-4 pyrimidine-pyrimidones (6-4s) in that gene, we synchronized XP variant and normal fibroblasts, irradiated them in early G1-phase, 12 or more hours prior to the scheduled onset of S phase, harvested them immediately or after allowing various times for repair, and analyzed the DNA for photoproducts in the HPRT gene, using quantitative Southern blotting. To incise the DNA at CPD, we used T4 endonuclease V; to incise at 6-4s, we first used photolyase and UV365nm to reverse CPD and then UvrABC excinuclease. Excision of CPD was rapid, preferential, and strand-specific, but there was no significant difference in rate between the two kinds of cells. The half life was 4 h in the transcribed strand of the gene and 6.5 h in the nontranscribed strand. For excision of CPD in the genome overall, this value is 12 h. Excision of 6-4s from either strand of the HPRT gene was extremely rapid and preferential in both kinds of cells, with a half life of approximately 30 min. The results indicate that the UV hypermutability of the XP variant cells cannot be caused by slower rates of repair of CPD and/or 6-4s in the target gene for mutagenesis.
Estimating point spectra using the Lanczos algorithm

An efficient method is presented for estimating the coefficients and roots of an autoregressive scheme where the roots are forced to lie on the unit circle. The spectrum of such a process is naturally interpreted to be a discrete measure and the algorithm is derived from the Lanczos method of approximating eigenvalues of a symmetric matrix. An extension is presented that is biased to detecting frequencies within a given interval.
The sleep-dream cycle and convulsion threshold

Electroconvulsive seizure threshold in the mouse was found to be lowered by reserpine and also by D-deprivation (REM-deprivation). D-deprivation plus reserpine produced a greater lowering than either alone. High positive correlations between the two effects across animals (mice more “sensitive” to reserpine were more sensitive to D-deprivation) suggests that the same or closely related mechanisms are involved.
A Scatterometer System for Laboratory Study of Polarimetric Electromagnetic Signatures of Icy Hydrometeors

Radar sensors with dual-polarization capability allow a better understanding and characterization of weather hazards, particularly hydrometeor particles. The knowledge of natural polarimetric hydrometeor scattering signatures, on the other hand, has been limited in theoretical calculations, simulations, and radar measurements. In this paper, an experimental approach was designed with the assistance of a controlled laboratory environment. An advanced vector network analyzer-based scatterometer system has been developed in harmony with an environmentally monitored anechoic chamber with special configurations for hydrometeor measurements. The polarimetric radar cross section (RCS) of various natural and man-made icy hydrometeor samples is measured across wide X-band frequencies and compared with theoretical modeling results. The dual-polarization radar variables and hydrometeor melting parameters are derived from the RCS measurements with interesting observations obtained. The described technology and results serve as the basis of a new hydrometer microphysics knowledge base for hydrometeor classification processing in the next-generation multichannel dual-polarized hazard monitoring radars.
Cigarette Excise Tax Structure and Cigarette Prices: Evidence From the Global Adult Tobacco Survey and the U.S. National Adult Tobacco Survey

INTRODUCTION The importance of tobacco tax structure in determining the relative prices of different tobacco products and brands has become increasingly recognized. The structuring of tobacco tax across products and brands within a country can impact the variability of prices within a country, shaping consumption and influencing tobacco users' incentives to switch down to cheaper alternatives in response to tax and price increases. METHODS Brand-specific data on the average prices paid for the top 5 cigarette brands in 13 countries were obtained from the Global Adult Tobacco Survey, and for the United States, data were obtained from the National Adult Tobacco Survey. The variability of cigarette prices paid across brands was analyzed in the context of each country's tobacco tax structure. RESULTS Countries with simpler cigarette tax structures, particularly those that emphasize specific taxes and do not involve tier-based taxes, exhibit less variability in the prices smokers pay for cigarettes across brands. CONCLUSIONS Increases in cigarette taxes in countries with simpler tax structures will be more effective in reducing cigarette smoking and its health and economic consequences than comparable tax increases in countries where tax structures are more complicated and there are greater opportunities for switching to cheaper brands in order to avoid a tax increase.