cssi/SciSciGPT-SciSciNet huggingface dataset:
Analysis of the emission line spectra of a solar flare observed from Skylab

The EUV emission spectra in the wavelength range 110–1900 A of the 5 September 1973 flare observed with the NRL slit spectrograph on Skylab are studied. The results are: (1) The chromospheric and transition-zone lines are greatly enhanced during the flare. In particular, the allowed lines are enhanced more than the intersystem lines. The Ni ii and P ii lines show the greatest enhancement with a factor of 800 increase in intensity. Other lines such as O i, C i, Si iii, S iii, S iv, O iv, O v, and N v show increases in intensity 10–100 times during the flare. (2) The chromospheric lines, although greatly enhanced during the flare, maintain their sharp and gaussian profiles and are not appreciably broadened. The transition zone lines, on the other hand, show a red-shifted component during the initial phase of the flare. The deduced downward velocity in the transition zone is 50 km s−1. In addition, there are large turbulent mass motions. The downward mass motion is probably caused by the pressure imbalance between the flare hot plasma at 13 × 106 K and the cooler plasma at 105 K. (3) The density of the 105 K flare plasma, as deduced from density-sensitive lines, is greater than 1012 cm-3. The depth of the 105 K plasma in the flare transition zone is only of the order of 0.1 km, giving a steep temperature gradient. Consideration of the energy balance between the conductive flux and the radiative energy losses shows that, indeed, the high density in the transition zone requires that its thickness be very small. This is a consequence of the maximum radiative efficiency at the temperature around 105 K in the solar plasma.
An approximate-solution-based numerical scheme for Stefan problem with time-dependent boundary conditions

An approximate—locally analytic in the time variable and globally analytic in the space variable—solution is developed for the one-dimensional Stefan problem with time-dependent boundary conditions. Because of local analyticity in time, the solution is accurate over time intervals that are much larger than the step size permitted by most numerical schemes. The solution is developed by reducing the governing partial differential equation (PDE) to two ordinary differential equations (OOE), and then simultaneously solving them along with the ODE for the moving-boundary interface condition. The resulting scheme requires the solution of only a single transcendental (algebraic) equation at each time interval for the time-step-averaged temperature gradient at the moving boundary. The position of the moving boundary and the temperature distribution at the end of the time interval are then simply evaluated using approximate analytical expressions. Good agreement with reference solutions is obtained.
Personnel References: Balancing Professional Responsibilities Against Potential Legal Action

Competent and qualified persons in our nation's schools are, perhaps, the most critical component of effective school programs. Without good teachers, administrators, and support
Polyaniline: Protonic Acid Doping to the Metallic Regime

Abstract “Polyaniline” has been synthesized in various forms both chemically and electrochemically in aqueous media. The quinoid-benzenoid-diimine form, an insulator, is doped by dilute aqueous protonic acids to the metallic regime ([sgrave] ∼ 5 ohm−1cm−1; compressed pellet) to give the corresponding iminium salt. The polymer is not oxidized during the doping process. This represents a new type of p-doping phenomenon in a conducting polymer. Both these forms of polyaniline are stable in the presence of air and/ or water. The doping process is reversed by treatment with aqueous alkali. The mechanism by which doping occurs is discussed.
Plagioclase of Hawaiian tholeiitic and alkalic magma parentages: distinctions based on REE, Sr, Ba, Hf, and Ta

¶To enhance the ability to distinguish tholeiitic from alkalic magma parentages by mineral compositions, I determined trace-element abundances in plagioclase separated from xenolithic gabbros of Mauna Kea volcano. These gabbros have origins in tholeiitic and alkalic magmas of the Hamakua postshield stage of Mauna Kea volcanism. Chondrite-normalized rare-earth element (REE) patterns for plagioclase show that highly calcic plagioclase, ≥ An78, from alkalic magma has greater light-REE/heavy-REE (LREE/HREE) ratios than less calcic plagioclase, An64–75, from tholeiitic magma (ratios, 22–33 vs < 20), suggesting that higher LREE/HREE ratios are inherent to plagioclase of alkalic magmas. However, with compositional evolution (i.e., to lower An), plagioclase REE patterns are of limited use for distinguishing tholeiitic from alkalic parentage because LREE/HREE ratios within each group increase and overlap in the range of ∼ 20–90. Sr, Ba, Hf, and Ta can also discern parentages as their abundances in plagioclase largely reflect abundances inherent to their parental magmas. The best expressions for identifying parentage use Sr abundances (Sr vs An; vs Ce/Yb; vs Sr/Ce), although Hf, Ba, and Ta abundances vs An and vs Ce/Yb are also useful – the distinctions due to tholeiitic plagioclase having relatively low Sr (∼ 500–1000 ppm), Ba (< 100 ppm), Hf (< 0.10 ppm), and Ta (< 0.05 ppm). These relationships help to distinguish between the effects of differentiation on trace-element abundances in plagioclase and their abundances owed to intrinsic concentrations in their magmas. They create compositional fields for tholeiitic and alkalic parentages that remain graphically separated even though differentiation may have enriched the plagioclase in incompatible elements.
Synthesis of anhydrosibiromycinone: a new method for the direct synthesis of pyrrolo-1,4-benzodiazepin-5-ones

Abstract Dimethylanhydroxibiromycinone ( 3 ) was prepared by the condensation of pyrrole aldehyde 5 with the sulfinamide anhydride from anthranilic acid 4 and demethylated to anhydrosibiromycinone ( 9 ).
Dollars, “Free Trade,” and Migration: The Combined Forces of Alienation in Postwar El Salvador

Driven by new conditions of desperation and alienation, mass migration in postwar El Salvador has continued unabated. While this migration could be seen as a way of “opting out” of ongoing class st...
Administration of Microaggregate Filtered Blood Using a Manual Infusion Pump

Administration sets containing in-line plastic blood pumps are commonly used to transfuse blood. Flow rates were measured while six units of whole blood and red blood cells were infused through a blood pump administration set coupled to either a large pore 260-micron filter or a 20-micron microaggregate blood filter. Using the same type of blood pump administration system and three units of whole blood, the flow rates achieved by the currently available microaggregate blood filters were compared. Results showed that despite a smaller pore size the 20-micron microaggregate blood filter achieved flow rates that were faster than or equal to those recorded for the larger pore (260-micron) filter. This was attributed to the larger filtration surface area possessed by the smaller pore filter, 140 cm2 versus only 30 cm2 for the 260-micron filter. All of the microaggregate filters studied were able to filter three units of whole blood at flow rates in excess of 80 ml/minute. There was no evidence of blood pump induced hemolysis. We concluded that a manual infusion pump can be used to transfuse microaggregate filtered blood rapidly enough to be acceptable for routine clinical or intraoperative use.
In vitro bactericidal activity of piperacillin, gentamicin, and metronidazole in a mixed model containing Escherichia coli, Enterococcus faecalis, and Bacteroides fragilis

An anaerobic, mixed model assay was used to study the bactericidal activities of piperacillin, gentamicin, and metronidazole, alone and in double- and triple-antibiotic combinations against a polymicrobial suspension of E. coli, E. faecalis, and B. fragilis. Only slight differences were noted with the agents when tested against single (10(5) cfu/mL inoculum) versus polymicrobic suspensions (10(6) cfu/mL final inoculum) of susceptible and resistant organisms. Contrary to previous reports in the literature, metronidazole was not active against E. coli in an anaerobic environment (even in the presence of B. fragilis) nor was the activity of metronidazole reduced against B. fragilis in the presence of E. faecalis. Gentamicin demonstrated excellent activity against E. coli when tested in a Bactron anaerobic chamber (5% hydrogen, 5% CO(2,) 90% nitrogen). The pH of the media was only reduced to 6.3-6.7, considerably higher than the pH range of 5-6 needed to significantly reduce the activity of aminoglycosides.
Experimental Upper Limit on the Magnetic Monopole Moment of Electrons, Protons, and Neutrons, Utilizing a Superconducting Quantum Interferometer

A superconducting quantum interferometer (magnetic flux sensitivity \ensuremath{\sim}${10}^{\ensuremath{-}17}$ Wb) is shown to be capable of directly detecting magnetic charge, in particular Dirac's quantized magnetic monopoles ($\mathrm{magnetic}\mathrm{flux}=\frac{h}{e}=4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}15}$ Wb). In samples free of Dirac monopoles, divB was determined to be less than 1.2\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}14}$ Wb/kg, while the magnetic charge of the neutron and of the proton (relative to the electron) were found to be less than ${10}^{\ensuremath{-}26}$ Dirac monopole per nucleon. The magnetic charge of the electron itself was measured to be less than 4\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}24}$ Dirac monopole.
Neuronal expression of TATA box-binding protein containing expanded polyglutamine in knock-in mice reduces chaperone protein response by impairing the function of nuclear factor-Y transcription factor

The polyglutamine diseases consist of nine neurodegenerative disorders including spinocerebellar ataxia type 17 that is caused by a polyglutamine tract expansion in the TATA box-binding protein. In all polyglutamine diseases, polyglutamine-expanded proteins are ubiquitously expressed throughout the body but cause selective neurodegeneration. Understanding the specific effects of polyglutamine-expanded proteins, when expressed at the endogenous levels, in neurons is important for unravelling the pathogenesis of polyglutamine diseases. However, addressing this important issue using mouse models that either overly or ubiquitously express mutant polyglutamine proteins in the brain and body has proved difficult. To investigate the pathogenesis of spinocerebellar ataxia 17, we generated a conditional knock-in mouse model that expresses one copy of the mutant TATA box-binding protein gene, which encodes a 105-glutamine repeat, selectively in neuronal cells at the endogenous level. Neuronal expression of mutant TATA box-binding protein causes age-dependent neurological symptoms in mice and the degeneration of cerebellar Purkinje cells. Mutant TATA box-binding protein binds more tightly to the transcription factor nuclear factor-Y, inhibits its association with the chaperone protein promoter, as well as the promoter activity and reduces the expression of the chaperones Hsp70, Hsp25 and HspA5, and their response to stress. These findings demonstrate how mutant TATA box-binding protein at the endogenous level affects neuronal function, with important implications for the pathogenesis and treatment of polyglutamine diseases.
Red squill— most specific of the raticides

This bulb of the lily family is extremely poisonous to mice and rats but relatively non-toxic to domestic animals and humans.
Affect control theory: Concepts and model

A current statement of affect control theory is provided with attention to the qualitative framework for analyses and the quantitative variables and processes involved in affective dynamics. The th...
A load‐sharing model: The linear breakdown rule

An n-component parallel system is subjected to a known load program. As time passes, components fail in a random manner, which depends on their individual load histories. At any time, the surviving components share the total load according to some rule. The system's life distribution is studied under the linear breakdown rule and it is shown that if the load program is increasing, the system lifetime is IFR. Using the notion of Schur convexity, a stochastic comparison of different systems is obtained. It is also shown that the system failure time is asymptotically normally distributed as the number of components grows large. All these results hold under various load-sharing rules; in fact, we show that the system lifetime distribution is invariant under different load-sharing rules.
The art of demonstration in anatomy instruction

As an educator, have you ever wondered why the students in the classroom learn so little despite the innumerable hours you have spent perfecting the lecture? Why, after a brief period of time, do students start losing attention and focus? Many lecturers have experienced this phenomenon, some more than others. To address this issue, in the setting of a fifty minute lecture we’ve included several demonstrations involving volunteer students and/or economical home created models. Several anatomical concepts, such as the configuration of pleura and thoracic structures and peritoneum and abdominal/pelvic structures, were demonstrated in the classroom using transparent plastic sheets and sleeves, cardboard boxes, plastic bottles and balloons, and often even the students themselves. Such activity was designed to spike the students’ curiosity, involvement, interest, and engagement for the length of the fifty minute lecture. These changes were implemented over several lectures during each eight week academic block, and the lectures with such demonstrations were interspersed between other traditional didactic lectures. To our satisfaction, not only did such non-traditional lecturing appear to help the students understand and learn better, but there was better attendance in these non-mandatory lectures, coupled with great enthusiasm, attention, and engagement during the lectures. Our goal in the classroom was to create an environment that helps students to learn effectively. This article presents a teaching approach that engages students by making them part of a classroom activity, which attracts the students’ attention and invokes their curiosity with inexpensive home-made anatomy models. Keywords: Active learning; Anatomy Models; Student engagement. Revista HUPE, Rio de Janeiro, 2014;13(4):46-51 doi: 10.12957/rhupe.2014.13947
Understanding applied communication inquiry: Researcher as organizational consultant

Abstract This essay defines applied communication inquiry from the point of view of the researcher operating as an organizational consultant and describes what investigators face when planning and conducting such inquiry. Avidly disagreeing with academics who separate so‐called “pure or basic research” from “applied research,” I argue that falsely dichotomizing inquiry in this way is both inaccurate and misleading. All high quality communication inquiry must meet certain conceptual criteria and be based in good decisions regarding critical issues which can either mediate or inhibit an investigation within any one of a variety of research settings. I present a consultancy model that explicates those critical issues which are important to conducting successfully communication inquiry in the field. I conclude by discussing the pedagogical implications of my definition and model for redesigning antiquated curricula in the communication research process and methodology.
Gauss and generalized inverses

Abstract Although Gauss did not formalize the notion of a generalized inverse, he provided the essential ingredients to produce one.
The chemical and physical properties of CrO2and tetravalent chromium oxide derivatives

Abstract The oxide of chromium (IV), Cr02, is a highly interesting compound for materials investigation in that it is ferromagnetic at room temperature and a good electrical conductor. The Curie temperature is 118°C, and the material can readily be demagnetized with little energy input. The electrical conductivity of this black compound is quite high for an oxide; it even rivals some of the metal conductors such as Mn and Gd at roomtemperature. Thls review describes procedures for preparing Cr02, presents its chemical and physical properties including the modifications observed with metal-ion substitutions, and discusses the reactions of Cr02 with other metal oxides together with the physical properties of the ternary products containing tetravalent chromium.
On the Redward Shift of Spectral Lines of Nebulae

The characteristics of a wave traveling in a medium in which the velocity of light is a function of time is considered and it is shown that one is able to account for the redward shift of spectral lines from distant nebulae on this basis. For simplicity, the function ${c}_{1}=c(1\ensuremath{-}\ensuremath{\alpha}t)$ is assumed and numerical calculations are made yielding a value of $\ensuremath{\alpha}=1.81\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}17}$ cm per sec. as being necessary to account for observed redward shift.
A novel BK virus-based episomal vector for expression of foreign genes in mammalian cells

Abstract A composite mammalian cell-E. coli shuttle vector was developed based on the human papova virus BK and pSV-neo. The vector contains a dioxin-responsive enhancer (DRE) controlling a mouse mammary tumor virus (MMTV) promoter for the inducible expression of inserted genes. In human cells the vector replicates episomally, presumably utilizing the BKV rather than the SV40 origin, and expresses the BK T/t antigens. A deletion in the late BK region precludes the expression of the core/capsid proteins VP1, VP2, and VP3, thereby preventing the infectious lytic cycle. HeLa cells which were transfected with this vector and selected for resistance to the antibiotic G418 maintained the construct primarily in episomal form during more than one year of continuous culture, with little or no integration into the host genome. Transformed cells cultured in higher concentrations of G418 contained higher copy numbers of the vector. This permits one to vary the dosage of an inserted gene easily and reversibly without the need of conventional amplification techniques and clonal analysis. Using a chloramphenicol acetyl transferase (CAT) reporter gene inserted downstream of the MMTV promoter, we found that CAT expression was greater in clones with higher vector copy number. CAT expression was inducible with 2,3,7,8-tetrachlorodibenzo-p-dioxin, but inducibility was found to be inversely proportional to the copy number. Transformation of bacteria with plasmid molecules retrieved from the mammalian host was efficient, making this vector well adapted for the screening of cDNA libraries for the ability to express a phenotype in mammalian cells. Moreover, DNA sequences were stable during long-term passage in mammalian cells; vector passaged continuously for more than one year retained fully functional bacterial genes for resistance to chloramphenicol and ampicillin.
The ligand- and microtubule assembly-induced GTPase activity of purified calf brain tubulin

Abstract Calf brain tubulin purified by means of ammonium sulfate fractionation, ion-exchange chromatography, and MgCl 2 precipitation contains a low level of Mg 2+ -dependent GTPase activity, the protein preparation being essentially homogeneous according to conventional procedures. Tubulin was freed from this possibly contaminant enzyme activity by Sephacryl S300 gel chromatography. Soluble tubulin itself showed a ligand-induced Mg 2+ -dependent GTPase activity in the presence of colchicine, but not of tropolone methyl ether, podophyllotoxin, or vinblastine. Tubulin also hydrolyzed GTP when assembling into microtubules. This reaction proceeded in a nonlinear fashion and was suppressed together with microtubule assembly by lowering the protein concentration under the critical concentration, adequately modifying assembly buffer conditions, or using Ca 2+ , tropolone methyl ether, podophyllotoxin, or vinblastine. The number of molecules of GTP hydrolyzed per molecule of tubulin polymerized was estimated to vary between 0.9 and 2.1, depending on whether morpholineethanesulfonate or phosphate assembly buffers were employed.
AzureBench: Benchmarking the Storage Services of the Azure Cloud Platform

Cloud computing is becoming mainstream for High Performance Computing (HPC) application development over the last few years. However, even though many vendors have rolled out their commercial cloud infrastructures, the service offerings are usually only best-effort based, without any performance guarantees. Cloud computing effectively saves the eScience developer the hassles of resource provisioning but utilization of these resources will be questionable if it can not meet the performance expectations of deployed applications. Furthermore, in order to make application design choices for a particular cloud offering, an eScience developer needs to understand the performance capabilities of the underlying cloud platform. Among all clouds, the emerging Azure cloud from Microsoft remains a challenge for HPC program development both due to lack of its support for traditional parallel programming support such as MPI and map-reduce and due to its evolving APIs. To aid the HPC developers, we present an open-source benchmark suite, Azure Bench, for Windows Azure cloud platform. We report comprehensive performance analysis of Azure cloud platform's storage services which are its primary artifacts for inter-processor coordination and communication. We also report on how much scalability Azure platform affords using up to 100 processors and point out various bottlenecks in parallel access of storage services. The paper also has pointers to overcome the steep learning curve for HPC application development over Azure. We also provide an open-source generic application framework that can be a starting point for application development for bag-of-task applications over Azure.
More evidence for coronary calcium as a measure of cardiovascular risk: has anything changed?

Prevention is a valued goal in both public health and clinical medicine, but the methods differ. In clinical medicine, the focus is on the individual patient and “personalized” assessment and intervention are highly desirable. Thus, in prevention of coronary heart disease (CHD), while the public health approach recommends dietary and other lifestyle measures that apply across a wide swath of the population, the clinical approach looks to identify the high-risk individuals within the population for targeted interventions. Therefore, clinicians dealing with individual patients wish to have predictive models and treatment algorithms that will enable personalized approaches. Ideally, each patient is assessed for a distinctive and specific risk of disease development or complications of an existing disease. As genomic and molecular research has advanced, the expectation of improved prediction and more specific personalization has become even more highly expected than in previous years.1
TAGging the target for damage control.

The structure of TAG, a DNA repair enzyme, reveals how evolutionary changes in the sequence of a conserved scaffold may enrich the mechanistic diversity of the DNA HhH glycosylase superfamily through a unique coupling of catalysis to substrate selectivity.
Microphotonic Channel Add-Drop Filter Based on Dual Photonic Crystal Cavity System in Push-Pull Mode

We demonstrate an add-drop filter based on a dual photonic crystal microcavity system that emulates a traveling-wave resonator. Realized on a 45nm SOI CMOS chip, the device shows 16dB through-port extinction and 1dB drop loss.
Regulation of guanosine 3',5' cyclic monophosphate in the rat pineal and posterior pituitary glands.

— Potassium and norepinephrine stimulate the accumulation of cyclic AMP and cyclic GMP in rat pineal glands and their efflux into the medium. The efflux of both cyclic nucleotides was blocked by probenecid. The accumulation and efflux of cyclic GMP, but not of cyclic AMP, depends upon the presence of intact nerve endings and extracellular calcium. The calcium-dependent release of norepinephrine caused by veratridine was accompanied by the efflux of both cyclic AMP and cyclic GMP. In contrast, the calcium-independent release of norepinephrine caused by tyramine was accompanied by the efflux of cyclic AMP but not cyclic GMP. Changes in cyclic GMP therefore, may be related to exocytosis from the sympathetic nerve endings in the gland. High concentrations of potassium also increased tissue levels of cyclic GMP in the posterior pituitary gland. Veratridine and potassium, but not norepinephrine, stimulated the efflux of cyclic GMP from this neurosecretory gland. Thus, the relationship between cyclic GMP and exocytosis may extend beyond sympathetic nerve endings. The enhanced accumulation of cyclic GMP in the pineal gland after potassium does not appear to be mediated by extracellular (released) norepinephrine. Desmethylimipramine blocked the norepinephrine-stimulated changes in cyclic GMP, but not those caused by potassium. Investigation of the possible relationship between cyclic GMP and release of neurotransmitters is complicated by the apparent seasonal variation in the response of pineal cyclic GMP to potassium or norepinephrine.
Astigmatic decay following small incision, self-sealing cataract surgery: One-year follow-up

Abstract Twenty patients who had phacoemulsification using a small, self-sealing incision were evaluated one year after surgery for astigmatic changes. Keratometric analysis was performed using the EyeSys™ photokeratoscope, and data for the 3 mm corneal zone for each patient were recorded. Results were compared with those reported for the one-week and onemonth postoperative periods. From one month to one year, a minimal amount of additional against-the-rule change in cylinder occurred. Because the range of changes was broad, it was difficult to predict the direction of astigmatic change (i.e., against the rule versus with the rule) that would occur over time for a given patient.
Influence of Electrode Coatings on Conduction Currents in Transformer Oil

ALTHOUGH the exact mechanism of conduction in dielectric liquids is still the subject of controversy, it has long been recognized that the surface state of the electrodes greatly influences the conduction process1. Recent experimental evidence2,3 has shown that this conduction process is very sensitive to the surface state of the cathode, in particular to the presence of an insulating oxide layer. While it is known that oxide layers on the anode influence the electric strength of liquids4, the influence of anode surface barriers or films on the conduction currents does not appear to have been studied.
Ambient formaldehyde source attribution in Houston during TexAQS II and TRAMP

An online data repository known as the Air Research Information Infrastructure (ARII) was used to discriminate large industrial sources of formaldehyde (HCHO) from mobile and secondary formaldehyde sources in Houston. Analysis of continuous online measurements at one urban and two industrial sites obtained during the summer of 2006 enabled us to isolate and evaluate major source factors associated with formaldehyde. The contribution of industrial sources to total atmospheric formaldehyde at the urban Houston site is estimated to be 17%, compared to 23% for mobile sources, 36% secondary formation, and 24% biogenic sources. The potential industrial sources include flares from petrochemical plants and refineries in the Port of Houston. The relative contribution of industrial source factors to ambient HCHO at the urban site increased to about 66% on some mornings, coinciding with the HCHO peak concentration. Secondary formation of HCHO during the day and night resulted from reactions of industrial olefins and other VOCs with OH or ozone. Some peak HCHO concentrations can also be linked to emission events of other VOCs, while a significant portion remains unexplained by the reported events. It is likely, based on the results from the SHARP campaign and our analysis, that some episodic emission events releasing primary HCHO are unreported to the Texas Commission on Environmental Quality (TCEQ).
A new interferometric technique for the determination of the electrophoretic mobility of macromolecules.

Abstract A novel device is described for measuring the electrophoretic mobility of monodisperse macromolecules. This apparatus, which is based upon a Twyman-Green interferometer, yields ±3% precision with runs lasting only 15 min; and it is suitable for temperatures and/or ionic strengths near or below physiological. Its operation is illustrated with bovine serum albumin, the apparent mobility of which is shown to vary strongly with the purity and concentration of the preparation.
An electronic flash lamp system to replace the traditional explosively driven light source

Electronic flash lamps are being developed at the Lawrence Livermore National Laboratory (LLNL). These lamps are intended to replace the traditional explosively driven Argon-gas filled light sources (Argon candles) that are currently used to provide illumination for high speed rotating mirror-framing cameras. At Livermore, we are developing an electronic flash lamp system that can match or exceed the light output of a traditional Argon candle. These systems utilize a Plasma Arc Lamp developed by PRISM Science Inc of Woburn, MA, USA. In the past, high-speed photography requiring explosively driven light sources were a one-time-only even that destroyed fixtures and optical alignment. The electronic flash lamp system, utilizing the Plasma ArC Lamp, will replace the explosively driven lighting systems and provide the capability to dry run experimental setups and repeat tests without damage to the experimental set-up. The electronic flash lamp system eliminates the problem of collateral damage to the experiment and does not add to the overall amount of explosives needed for single test. Since the Pulsed-Power driver is remotely located, only the flash lamp itself is destroyed when the explosive shot is fired. The flexible geometry of this light source also enables the user to create complex light patterns as well as photograph very large areas with a single lighting system. This electronic flash lamp system will provide an extremely bright, stable, and repeatable light source for rotating-mirror framing cameras operating at one million frames per second, using both black & white or color films. The design of the Pulsed-Power driver and the flash lamp, along with experimental data and results will be discussed.
Government Growth and Professionalism in U.S. State Legislatures

This article analyzes the professionalization of American state legislatures since the 1960s and expands on previous studies by considering the strategic incentives of members. Fiorina and Noll's (1978a, 1978b) theory that reelection-minded legislators serve as �ombudsmen to the bureaucracy� on behalf of their constituents suggests that legislatures have professionalized in response to growth in public spending in order to strengthen members' abilities to handle increased facilitation duties. I used longitudinal analysis and instrumental variables regression to test this hypothesis and disentangle causal directionality, since professional legislators may have the means and incentive to spend more than their citizen counterparts. Both methods revealed empirical support for the Fiorina and Noll hypothesis that spending increases caused legislators to become more professional.
Physical and Chemical Groundwater Remediation Technologies

Groundwater is the main source of drinking water as well as agricultural and industrial usage. Unfortunately, groundwater quality has been degraded due to improper waste disposal practices and accidental spillage of hazardous chemicals. Therefore, it is critical that the groundwater contamination be prevented and the contaminated groundwater at numerous sites worldwide be remediated in order to protect public health and the environment. This chapter provides an overview of relevant regulations, general remedial approach, and most commonly used physical and chemical groundwater remediation technologies. The remediation technologies include pump-and-treat, in-situ air sparging, in-situ flushing, and permeable reactive barriers. The process description, applicability, limitations and a case study for each of these technologies are also presented.
Purpose-Driven Leadership The Spiritual Imperative to Guiding Schools Beyond High-Stakes Testing and Minimum Proficiency

The educational leadership discourse is being challenged to include a spiritual voice in its conversation. Spirituality is defined as the part of life through which individuals make meaning and understanding of the world. It includes the esoteric exercise of personal critical reflection and forms the basis for values and principles that inform individual personal and professional behavior. This article examines purposive leadership, a concept grounded in what Cornel West called prophetic spirituality. It suggests educational leaders who build their professional practice in purpose-driven leadership clearly understand the multidimensional aspects of their daily challenges and yet find the inner strength to resist hegemonic structures and forms of oppression and systemic inequities in the educational system. These leaders' perceptions are not limited to proficiencies and minimum competencies but are clearly focused on ontological pursuits, academic and intellectual engagements, and projects fostering studen...
Textons, contours and regions: cue integration in image segmentation

The paper makes two contributions: it provides (1) an operational definition of textons, the putative elementary units of texture perception, and (2) an algorithm for partitioning the image into disjoint regions of coherent brightness and texture, where boundaries of regions are defined by peaks in contour orientation energy and differences in texton densities across the contour. B. Julesz (1981) introduced the term texton, analogous to a phoneme in speech recognition, but did not provide an operational definition for gray-level images. We re-invent textons as frequently co-occurring combinations of oriented linear filter outputs. These can be learned using a K-means approach. By mapping each pixel to its nearest texton, the image can be analyzed into texton channels, each of which is a point set where discrete techniques such as Voronoi diagrams become applicable. Local histograms of texton frequencies can be used with a /spl chi//sup 2/ test for significant differences to find texture boundaries. Natural images contain both textured and untextured regions, so we combine this cue with that of the presence of peaks of contour energy derived from outputs of odd- and even-symmetric oriented Gaussian derivative filters. Each of these cues has a domain of applicability, so to facilitate cue combination we introduce a gating operator based on a statistical test for isotropy of Delaunay neighbors. Having obtained a local measure of how likely two nearby pixels are to belong to the same region, we use the spectral graph theoretic framework of normalized cuts to find partitions of the image into regions of coherent texture and brightness. Experimental results on a wide range of images are shown.
Onset and Development of Natural Convection Above a Suddenly Heated Horizontal Surface

The onset and development of flow in a thick horizontal layer subject to a near-constant flux heating from below has been studied experimentally. The overall heat-flux-based Rayleigh number, Ra * , ranges from 2 X 10 8 to 7 X 10 10 . Flow visualization shows the growth and breakdown of a conduction layer adjacent to the heated surface. Convection is characterized by the release of warm meandering plumes and thermals from a boundary layer. The planform of convection at the heated surface begins with a pattern of small spots suggestive of Benard cells. Some of these cells expand, forming a larger cell pattern. This continues until a quasi-steady state is reached in which the former cell boundaries form a slowly moving pattern of warm lines on the heated surface. The lines are believed to be the source of the plumes and thermals. Quantitatively, the onset of convection occurs at a constant (critical) Rayleigh number based on the conduction layer thickness, Ra 6 . Based on the first observation of fluid motion, this critical Rayleigh number is approximately 1300. Based on the heated surface temperature the critical Rayleigh number is 2700.
The management of abruptio placentae

Abstract The 54 cases of abruptio placentae occurring in 18,202 deliveries have been studied. In the 15 cases of the mild group, interference was almost always unnecessary and their chief importance was the fetal loss due to prematurity and asphyxia. In the 31 cases of moderate severity with 34 babies, the fetal mortality was 64.7 per cent. Five cesarean sections were done, the remainder being delivered through the normal passages. Of the eight severe cases, three were treated by immediate cesarean section, four were successfully treated by conservative treatment and one was saved by combined treatment. All babies were dead when treatment was started. There was no maternal mortality in the total series. Total fetal mortality was 58.6 per cent.
THIN CONDUCTIVE CONCRETE OVERLAY FOR BRIDGE DECK DEICING AND ANTI-ICING

Concrete bridge decks are prone to ice accumulation. Bridge decks freeze before the roads approaching them freeze, making wintry highway travel treacherous. Road salts and deicing chemicals are effective for ice removal but cause damage to concrete and corrosion of reinforcing steel in concrete bridge decks. The resulting rapid degradation of existing concrete pavements and bridge decks is a major concern to transportation and public-works officials. The use of insulation materials for ice control and electric or thermal heating for deicing have been attempted, with unsatisfactory results. Conductive concrete is a cementitious admixture containing electrically conductive components to attain high and stable electrical conductivity. Due to its electrical resistance and impedance, a thin conductive concrete overlay can generate enough heat to prevent ice formation on a bridge deck when connected to a power source. In 1998, Yehia and Tuan, at the University of Nebraska-Lincoln, developed a conductive concret...
Path Clearance for Emergency Vehicles Through the Use of Vehicle-to-Vehicle Communication

The study described in this paper evaluated and tested a new strategy to enable emergency response vehicles (EVs) to navigate through congestion at signalized intersections more efficiently. The proposed strategy involves the use of vehicle-to-vehicle communication to send messages to alert vehicles to the approach of the EV and to provide specific instructions on maneuvering to allow the EV to proceed through congested signalized intersections as quickly as possible. This movement is achieved by creation of a split in the vehicle queue in one lane at a critical location to allow the EV to proceed at its desired speed but minimize the disruption to the rest of the traffic. The proposed method uses kinematic wave theory (i.e., shock wave theory) to determine the critical point in the vehicle queue. The proposed method is simulated in a microscopic traffic simulator for evaluation. The results show that this strategy can significantly shorten the travel time for EVs through congested signalized intersections.
Characterization of a well resolved supramolecular ice-like (H2O)10 cluster in the solid state

The conformation of a previously observed ice-like water cluster in the solid state proves to be robust to geometric changes in its surroundings and the hydrogen bonded arrangement is finally revealed in detail.
The Imagination of Place and Tourism Consumption: A Case Study of Lijiang Ancient Town, China

Abstract Tourism consumption has been conceptualized either as a free pursuit of pleasure and escape or a highly rationalized activity. Based on questionnaire surveys of 483 tourists and personal interviews of 18 tourists concerning Lijiang Ancient Town, a World Heritage site in China, this article contends that tourism consumption neither draws on freedom of choice nor conforms to the rigidities of predetermined norms. Instead, evidence suggests that tourism consumption dwells in the endless negotiations between tourists’ imagination, their economic and cultural capital, and the norms and values embedded in their destinations. Following Ateljevic's work on circuits of tourism, this paper has two objectives. First, it will analyse the touristic imagination of Lijiang Ancient Town and examine how this imagination shapes tourists’ practices of consumption. Secondly, the paper will explore the multi-sensory practices of consumption and how these practices transform Lijiang's heritage landscapes. The paper ar...
Bound-state, Bethe—Salpeter solutions with conjugate pairs of complex coupling constants

Solutions are obtained to the Bethe-Salpeter equation describing bound states of two massive scalars interacting via the exchange of a third, massive scalar. Covariance of the equation implies that the interaction is retarded, and in part because the energy appears more than once in the equation, a Hamiltonian for the bound state does not exist. Thus in contrast to the Schrodinger equation, the Bethe-Salpeter equation is solved by specifying the energy and solving for the coupling constant as an eigenvalue. Although the Bethe-Salpeter equation is derived from a Lagrangian with real coupling constants, depending on the value of the energy and the masses of the scalars, some values of the coupling constant that satisfy the Bethe-Salpeter equation are complex and always occur in conjugate pairs. The unexpected existence of solutions with real energy and a complex coupling constant raises the possibility that there are also resonance solutions with real values of the coupling constant and complex energy.
Premenstrual Syndrome: Psychiatric, Physiological, and Psychosocial Perspectives

Although social workers often work with client systems affected by premenstrual syndrome (PMS), little information has been made available to guide their work. This article reviews the literature on PMS and presents recent advances from psychiatric, physiological, and psychosocial perspectives. Clinical and policy issues also are examined in light of the recent inclusion of PMS in the appendix of the revised edition of the DSM-III.
Using high performance systems to build collections for a digital library

Nothing is more distributed than the Web, with its content spread across thousands of servers. High performance hardware and software is essential for an effective download, analysis, and organization of this content. We describe our experience with a highly parallel Web crawling system (Mercator) to construct - automatically - collections of scientific resources for the National Science Digital Library.
Time-dependent phase response of fluid interface to optical excitation

Optical excitation of a fluid interface involves both momentum exchange and thermal effects. A time-resolved phase study has shown agreement with our combined model of the two effects which vary significantly in time scale.
Determination of mixed-mode stress intensity factors, fracture toughness, and crack turning angle for anisotropic foam material

A numerical and experimental investigation for determining mixed-mode stress intensity factors, fracture toughness, and crack turning angle for BX-265 foam insulation material, used by NASA to insulate the external tank (ET) for the space shuttle, is presented. BX-265 foam is a type of spray-on foam insulation (SOFI), similar to the material used to insulate attics in residential construction. This cellular material is a good insulator and is very lightweight. Breakup of segments of this foam insulation on the shuttle ET impacting the shuttle thermal protection tiles during liftoff is believed to have caused the space shuttle Columbia failure during re-entry. NASA engineers are interested in understanding the processes that govern the breakup/fracture of this material from the shuttle ET. The foam is anisotropic in nature and the required stress and fracture mechanics analysis must include the effects of the direction dependence on material properties. Material testing at NASA Marshall Space Flight Center (MSFC) has indicated that the foam can be modeled as a transversely isotropic material. As a first step toward understanding the fracture mechanics of this material, we present a general theoretical and numerical framework for computing stress intensity factors (SIFs), under mixed-mode loading conditions, taking into account the material anisotropy. We present SIFs for middle tension – M(T) – test specimens, using 3D finite element stress analysis (ANSYS) and FRANC3D fracture analysis software. SIF values are presented for a range of foam material orientations. Mode I fracture toughness of the material is determined based on the SIF value at failure load. We also present crack turning angles for anisotropic foam material under mixed-mode loading. The results represent a quantitative basis for evaluating the strength and fracture properties of anisotropic foam insulation material.
RhoH, a hematopoietic-specific Rho GTPase, regulates proliferation, survival, migration, and engraftment of hematopoietic progenitor cells.

Rho guanosine triphosphatases (GT-Pases) are recognized as critical mediators of signaling pathways regulating actin assembly, migration, proliferation, and survival in hematopoietic cells. Here, we have studied a recently identified hematopoietic-specific Rho GTPase, RhoH. Unlike most members of the Rho GTPase family, RhoH is GTPase deficient and does not cycle between GTP- and guanosine diphosphate (GDP)–bound forms, suggesting that regulation of RhoH expression may be critical in its activity. We found that RhoH is expressed in murine hematopoietic progenitor cells (HPCs) and fully differentiated myeloid and lymphoid lineages. In cytokine-stimulated HPCs, knockdown of RhoH expression via RNA interference stimulates proliferation, survival, and stromal cell-derived factor-1α (SDF-1α)–induced migration in vitro. Conversely, RhoH overexpression in these cells via retrovirus-mediated gene transfer is associated with impaired activation of Rac GTPases, reduced proliferation, increased apoptosis, and defective actin polymerization and chemotaxis. In vivo, HPCs with RhoH overexpression demonstrate defective hematopoietic reconstitution capability compared with control vector-transduced cells. Our results suggest that RhoH serves as a negative regulator of both growth and actin-based function of HPCs possibly via suppression of Rac-mediated signaling.