cssi/SciSciGPT-SciSciNet huggingface dataset:
Synthesis and structure of smooth, superhard TiN/SiNx multilayer coatings with an equiaxed microstructure

Abstract TiN coatings have been widely used in various tribological applications. However, TiN coatings predominantly grow with a columnar grain structure, and these columnar grain boundaries become the sites for crack initiation, resulting in premature failure of TiN coatings. In this paper, we report the use of amorphous SiN x to periodically interrupt the growth of TiN in order to suppress the columnar structure. The growth was performed in a dual-cathode unbalanced reactive magnetron sputtering system. The resulting TiN/SiN x multilayer coatings, when deposited under optimum conditions (TiN layer thickness=2.0 nm, SiN x layer thickness=0.5 nm and substrate bias=−80 to –90 V) are smooth and exhibit an equiaxed grain structure with no evidence of columnar growth. The highest hardness is in excess of 45 GPa.
Anomalous field emission from Al2O3 coated Si tips

Abstract The emission properties of Al 2 O 3 coated Si field emitters were found to be radically different from any others reported to date. Silicon field emitter arrays were coated with ultrafine aluminum oxide powders by dielectrophoresis. The emission threshold, corresponding to a current of 10 pA, was 0.25 V/mm. The current–voltage ( I – V ) plots of the Al 2 O 3 coated Si field emitter arrays were steep, with a distinct deviation from Fowler–Nordheim (F–N) behavior. The emission showed a slow but distinct increase or decrease of current with time depending on the magnitude of the current. This behavior could be approximated with an exponential function. We suggest a tentative explanation in terms of “field emission induced secondary electron emission”, i.e. the generation of a secondary electron cascade by the interaction of the field emitted electrons with crystallites comprising the porous aluminum oxide coating.
Studies in magnetochemical engineering. Part III: Experimental applications of a practical model for high-gradient magnetic separation to pilot-scale coal beneficiation

The computer implementation and experimental verification of the practical model for high-gradient magnetic separation (HGMS) based on particle buildup and feed characteristic, developed in Part II, are described. It is shown that the new model can be used to satisfactorily predict the grade, recovery and concentration breakthrough observed in pilot-scale experimental studies of HGMS for the removal of sulfur and ash from water slurries of several pulverized Eastern coals. The experimentally verified model can be used to quantitatively identify the tradeoff of separation variables so as to optimize the magnetic removal of sulfur and ash from pulverized coal. The model can also be used to assess the technical and economical feasibility of the magnetic beneficiation of pulverized coal without extensive experimental tests.
Restoring the Vegetation of Mined Peatlands in the Southern Rocky Mountains of Colorado, U.S.A.

South Park is a high-elevation, semi-arid, treeless intermountain basin in central Colorado. A few extreme rich fens occur on the western margin and in the center of South Park where regional and local groundwater flow systems discharge to the ground surface. Over the past 40 years there has been extensive peat mining in these fens, but restoration methods have yet to be developed and successfully applied. The first part of this study compared the naturally reestablished vegetation on six mined peatlands with six pristine sites, while the second part of the study tested different revegetation techniques in 27 plots with varying depths to the water table. The six mined sites had only 30 plant species as compared with 122 species in the unmined sites; 43% of the species in the mined sites were not present in the undisturbed fens. Even after 40 years the sedges and willows that dominate the undisturbed sites were largely absent on the mined sites. The revegetation experiments seeded eight species, transplanted Carex aquatilis (water sedge) seedlings, transplanted rhizomes from six species, and transplanted four species of willow cuttings. Of the eight species seeded, only Triglochin maritima (arrowgrass) germinated and established seedlings. C. aquatilis seedlings, rhizome transplants of C. aquatilis, Kobresia simpliciuscula (elk sedge), and Juncus arcticus (arctic rush), and willow cuttings all had differing patterns of survival with respect to the annual maximum height of the water table. These results indicate that the dominant species can be successfully reintroduced to mined surfaces with the appropriate hydrologic conditions, but human intervention will be necessary to rapidly re-establish these species. The slow rate of peat accumulation means that restoration of the mined fens will require hundreds, if not thousands, of years.
The generation of magnetic fields and electric currents in cometary plasma tails

Due to the folding of the interplanetary magnetic field into the tail as a comet sweeps through the interplanetary medium, the magnetic field in the tail can be built up to the order of 100 gammas at a heliocentric distance of about 1 AU. This folding of magnetic flux tubes also results in a cross-tail electric current passing through a neutral sheet. When streams of enhanced plasma density merge with the main tail, cross-tail currents as large as 1 billion A may result. A condition could arise which causes a significant fraction of this current to be discharged through the inner coma, resulting in rapid ionization. The typical time scale for such outbursts of ionization is estimated to be of the order of 10,000 sec, which is in reasonable agreement with observation.
Whole genome amplification strategy for forensic genetic analysis using single or few cell equivalents of genomic DNA

Evidentiary items sometimes contain an insufficient quantity of DNA for routine forensic genetic analysis. These so-called low copy number DNA samples (< 100 pg of genomic DNA) often fall below the sensitivity limitations of routine DNA analysis methods. Theoretically, one way of making such intractable samples amenable to analysis would be to increase the number of starting genomes available for subsequent STR (short tandem repeat) analysis by a whole genome amplification strategy (WGA). Although numerous studies employing WGA have focused primarily on clinical applications, few in-depth studies have been conducted to evaluate the potential usefulness of these methods in forensic casework. After an initial evaluation of existing methods, a modified WGA strategy was developed that appears to have utility for low copy number forensic casework specimens. The method employs a slight, but important, modification of the "improved primer extension preamplification PCR" method (I-PEP-PCR), which we term mIPEP (modified-I-PEP-PCR). Complete autosomal STR and Y-STR (Y chromosome short tandem repeat) profiles were routinely obtained with 5 pg of template DNA, which is equivalent to 1-2 diploid cells. Remarkably, partial Y- and autosomal STR profiles were obtained from mIPEP-treated DNA recovered from bloodstains exposed to the outside environment for 1 year whereas non-mIPEP-treated samples did not produce profiles. STR profiles were obtained from contact DNA from single dermal ridge fingerprints when the DNA was subjected to prior mIPEP amplification but not when the mIPEP step was omitted.
Reaction profiles in sulfurnitrogen chemistry I. The isomerization of cis thionylimide, HNSO, to cis thiazyl-S-hydroxide, HOSN

Abstract A study of the energy changes which occur in the course of the isomerization of cis thionylimide to cis thiazyl-S-hydroxide has been carried out using MNDO molecular orbital calculations. The reaction is characterized by a standard enthalpy charge of 3–7 kcal/mol. The reaction proceeds through a cyclic transition state with an enthalpy of activation of 76 kcal/mol. The nature of electronic structures of the reactant and product molecules and the transition state complex have been studied using energy localized molecular orbitals. The transition state was found to be a cyclic structure wherein the hydrogen atom is about equally bonded to both the oxygen and nitrogen atoms.
Modeling influences on eating behavior

Abstract Some aspects of social influence on eating behavior have been examined but no studies have looked at direct influences of one person's eating behavior on that of another. Two experiments assessed whether people model rate of eating and amount of food consumed by another person. In Experiment I, female college students ate a standardized luncheon with a confederate-model peer, who ate her lunch at a predetermined fast (12 min) or slow (25 min) rate. Subjects who ate with fast-eating confederate-models consumed their lunches at a significantly faster rate than subjects who ate with slow-eating confederate-models. In Experiment II, same and opposite sex pairs of subjects and confederate-models participated in a “cracker tasting” task. The confederate-model ate either a high (40) or low (10) number of crackers in 7 min. Subjects eating with a high consumption male confederate-model ate more crackers than subjects who ate with a low consumption male or female confederate-model. But, subjects who ate with a high consumption female confederate-model did not differ from the other groups in number of crackers eaten. These findings may be important for treating obesity, if modeling also occurs in natural situations.
Metrology and analysis of two-dimensional SEM patterns

A variety of techniques to characterize the lithographic quality of top-down two-dimensional patterns are described. Beginning with a top-down SEM micrograph, image processing and feature edge detection are used to extract a polygon representation of the printed pattern. Analysis on the polygon yields metrics such as corner rounding radius, feature area, and line edge roughness. Comparison of two shapes (for example, actual compared to desired, mask compared to wafer, or before etch compared to after etch) produces metrics such as overlapping area and the critical shape difference. Numerous examples of the utility of this approach will be given for SEM images of masks and wafers. The result is a set of numeric metrics of two-dimensional pattern fidelity applicable to lithographic evaluation, improvement and control.
GROWTH AND TISSUE FORMATION FROM SINGLE GERANIUM CELLS FROM VIRUS-INFECTED GERANIUMS*

Single geranium (Pelargonium hortorum, Bailey) cells from callus isolated originally from stem tips of virus-infected plants were grown in microculture chambers in liquid Murashige and Skoog medium supplemented with 0.1 mg per liter of α-naphthalane acetic acid and 10.0 mg per liter of kinetin. Four of 1,000 of these single cells divided in the microculture chamber and produced colonies of 15 to 20 cells in 9 to 16 days. In all of the cases the plane of the first few cell division was at right angles to the long axis of the cells. Subsequently, one of the masses of cells obtained from a single cell, when transferred to solid Murashige and Skoog medium, established itself as a clone of callus tissue. Although the yield was low, the results were encouraging for the ultimate production of plants. These results suggested that, just as virus-free tobacco plants have been induced from single cell clones from certain tobacco species, virus-free single geranium cells may be useful to establish single cell clones from which pathogen-free geranium plants may be induced to differentiate.
Invariant imbedding, method of characteristics, and parameter estimation.

Parameter estimation in a physical system from observed data is carried out by a method which combines invariant imbedding formalism and the method of characteristics. This avoids the necessity of making use of an initial guess for the parameter necessary if one adopts quasilinearization techniques. Numerical results for a simple one parameter system is presented.
Role of Hyperplasia in Vascular Lesions of Cholesterol-fed Rabbits Studied with Thymidine-H3 Autoradiography

Rabbit aorta and coronary vessels were studied with thymidine-H3 and autoradiography. They were found to comprise an extremely stable population of cells, the latter probably even more stable than the former. Compensatory repair by means of regeneration at sites of bifurcation seems inadequate. This in part may explain the susceptibility of these areas to the development of atherosclerotic lesions. Proliferation, although sequentially secondary to fatty infiltration, plays an active role in the pathogenesis of cellular atherosclerotic lesions as seen in the rabbit. Foam cells possess the ability to synthesize DNA even when incorporated within the atherosclerotic lesion. Arguments in support of and opposed to some of the current hypotheses for the pathogenesis of atherosclerosis have been presented.
Universal multi-dimensional scaling

In this paper, we propose a unified algorithmic framework for solving many known variants of MDS. Our algorithm is a simple iterative scheme with guaranteed convergence, and is modular; by changing the internals of a single subroutine in the algorithm, we can switch cost functions and target spaces easily. In addition to the formal guarantees of convergence, our algorithms are accurate; in most cases, they converge to better quality solutions than existing methods in comparable time. Moreover, they have a small memory footprint and scale effectively for large data sets. We expect that this framework will be useful for a number of MDS variants that have not yet been studied. Our framework extends to embedding high-dimensional points lying on a sphere to points on a lower dimensional sphere, preserving geodesic distances. As a complement to this result, we also extend the Johnson-Lindenstrauss Lemma to this spherical setting, by showing that projecting to a random O((1/µ2) log n)-dimensional sphere causes only an eps-distortion in the geodesic distances.
Complex service systems: Integration and adaption

From a Venn diagram perspective, there are seven possible venues to consider when one looks at possible mixtures of services, integration and adaptation. Individually, we can have 1) a services system domain, 2) a spatially integrated system, and 3) a temporally adaptive system. When combined two at a time, we can have 4) an integrated service system, 5) an adaptive service system, and 6) a complex - integrated and adaptive - system. When all three combined, we can have 7) a complex - integrated and adaptive - service system. All seven venues are appropriately considered.
Some effects of gum chewing on gastric acidity in healthy individuals.

The effect of gum chewing on gastric acidity has been studied in the case of 12 individuals from whom normal gastric curves had previously been determined. The chewing of gum depressed the gastric acidity of two-thirds of the individuals during the period of an hour. Both the total and the free acidity were depressed in five-sixths of the individuals for the first half hour. The maximum total acidity was less in eleven of the twelve subjects when gum was chewed. However, the time required to reach this maximum did not vary materially from the time required when no gum was chewed.
Time compression-rapid steel tooling for an ever-changing world

Abstract As the race to get a product to market increases in speed, the drive for tooling lead times to decrease will become greater. This drive in time compression in the manufacturing sector leads to unique opportunities to create tooling via non-traditional methods that dramatically reduce lead times while not sacrificing mechanical properties. Rapid tooling, fabricated at The Pennsylvania State University’s P/M Lab, uses a powder metallurgy process to combine the processing of various metals and or ceramic powders to form a tool set with tailored mechanical properties. The new process has potential uses in the automotive, toy, electronics, cosmetics, fashion, medical, packaging, and metal die casting industries, as well as significant implications for the manufacturing industry as a whole. Recent reports estimate that total profits on new products are reduced by as much as 60% by a company's inability to get the product to market quickly. With increasing part complexity and requirements for long production runs, tooling has become an expensive process that requires long lead times to manufacture. This lengthens the amount of time from ‘art to part’. Rapid tooling via stereolithography (SLA), filled epoxies, etc., have been stopgap measures to produce limited prototyping runs (from 10 to 500 parts). This gives poor dimensional precision and does not allow for limited production runs of 1000+ parts. The method of producing prototype tooling with a powdered metal process has been developed that produces tooling with 1150 MPa TRS strength, hardness greater than 35 HRC and shrinkage less than 0.4%. The surface finish of the tool set as sintered is approximately 1.5–2 μm, but can be polished to approximately 0.2 μm. This tooling process manufactures production ready tooling that will perform extended cycle runs (100 000+). Manufacturing of this tooling takes 1 week and will compare favorably with production grade steel tooling. The process starts with a rapid prototyped model made by whatever RP process is desired or a machined master. For this study a Sanders rapid prototyping machine was used to fabricate the model. After the model of the tool set is made, a silicone rubber negative is cast around that model. After the silicone rubber mold is hardened, slurry of metal powders and polymers is poured into the mold to create the green tool set. The tool set is left to cool, and then removed from the silicone rubber mold. The tool set is then debound and sintered to produce a final tool set with properties approaching hardened tool steel.
Use of a program understanding taxonomy at Hewlett-Packard

Summarizes the use of a program understanding taxonomy developed at Hewlett-Packard. The primary use of the taxonomy has been in the creation of a company internal document called the Software Tools Report. The Software Tools Report is a selection and evaluation guide to software tools that addresses key company software engineering areas which include program understanding. A description of the Report, how it was created, and how it is used is given. >
Electrophysiological effects of Mu-selective opioids on hilar neurons in the hippocampus in vivo.

Although mu-selective opioids have been shown to produce dramatic effects on neurons within the CA1 and dentate regions of the rat hippocampus, little is known regarding their effects on neurons within the hilus, a region of potential importance in several disease states. We studied the neurophysiologic responses of hilar neurons recorded extracellularly to electrophoretic [D-Ala2, NMe-Phe4, Gly-ol]-enkephalin (DAMGO) and systemic morphine (MS) in anesthetized rats. We found that hilar cells could be readily divided into two categories, based on their pattern of spontaneous activity and response to perforant path stimulation. Cells that discharged in a bursting-type pattern formed a homogeneous group electrophysiologically. The response of these cells to opioids was dependent on route of administration, with the spontaneous activity of all cells tested increasing following electrophoretically administered DAMGO, and remaining unchanged in response to systemic MS. Cells that discharged in a non-bursting pattern showed some electrophysiologic variation, as well as some differential response to opioids. However, the spontaneous activity in the majority of non-bursting cells increased following electrophoretic administration of DAMGO. In these cells, MS produced similar, although usually less dramatic, effects. Comparison with intracellular data suggests that the bursting cells in our study correlate most closely with hilar “mossy cells,” while the non-bursting action potentials were recorded from other cells, primarily putative interneurons. We conclude that mu-selective opioids produce excitation of mossy cells, probably through an indirect mechanism, with the primary site of action occurring on cells in the granule cell layer. This regional excitation may help to mediate the effects of locally administered mu-selective opioids within the dentate gyrus. © 1995 Wiley-Liss, Inc.
Development of food preferences

Using a developmental systems perspective, this review focuses on how genetic predispositions interact with aspects of the eating environment to produce phenotypic food preferences. Predispositions include the unlearned, reflexive reactions to basic tastes: the preference for sweet and salty tastes, and the rejection of sour and bitter tastes. Other predispositions are ( a) the neophobic reaction to new foods and (b) the ability to learn food preferences based on associations with the contexts and consequences of eating various foods. Whether genetic predispositions are manifested in food preferences that foster healthy diets depends on the eating environment, including food availability and child-feeding practices of the adults. Unfortunately, in the United States today, the ready availability of energy-dense foods, high in sugar, fat, and salt, provides an eating environment that fosters food preferences inconsistent with dietary guidelines, which can promote excess weight gain and obesity.
Preparation and Spectroscopic Characterization of MoS2 and MoSe2 Nanoparticles

Abstract In this manuscript, we report an experiment for the upper division chemistry laboratory involving the synthesis and characterization of molybdenum (IV) chalcogenide nanoparticles. The reaction is a straightforward synthesis between molybdenum hexacarbonyl and sulfur or selenium. Students follow the progress of the reaction via monitoring the carbonyl stretch using Fourier transform infrared (FTIR) spectroscopy. The nanoparticles are found to absorb light in the UV region of the spectrum compared with the near IR for bulk molybdenum (IV) chalcogenides. Further, the particles also exhibit a blue fluorescence when excited in the UV region. Students can easily complete the experiment in two 3‐hr laboratory periods, one focusing on the synthesis and the other on the spectroscopic characterization.
Educational policy and the courts: The case of Washington, D. C.

Since 1954, the courts have assumed a great deal of leadership in setting educational policy. In each instance, citizen dissatisfaction with the educational process has led to court suits, often resulting in massive or disruptive changes. However, the blame cannot and should not be leveled on the courts. The problems and solutions have clearly rested with boards of education, local and state legislative bodies, and executives. Their failure to respond affirmatively to various issues is clearly the problem. The District of Columbia presents a marvelous example of governmental inaction and what can result. This paper provides a brief judicial history of education in the District and what the implications have been. The reader must keep in mind that although the District is a city, its government, especially the Board of Education, functions as though on a state level. Thus, court decrees concerning education in Washington, D. C. may give other states the incentive to improve the education of all students, regardless of ethnic or economic background.[/p]
Seakeeping Characteristics of a Wave-Adaptive Modular Unmanned Surface Vehicle

Sea-keeping characteristics of a wave-adaptive modular catamaran, developed by Marine Advanced Research Inc., is studied using at-sea experiments and dynamic modeling. The vehicle is based on the Proteus design and is supported by two inflatable pontoons with each pontoon attached to a center payload tray using an independent suspension system connected in such a way that the demi-hulls perform somewhat independent motions through a wave field. The suspension system is designed to isolate the center payload tray from the motions induced by waves incident on the demi-hulls. The vehicle is propelled by two water jets and is capable of achieving speeds of 8–15 knots. Accelerometers have been mounted on the pontoons and the center payload tray of the vehicle and field tests in the open ocean have been carried out to study sea-keeping properties of the vehicle. Heave and surge motions for the cases of following seas, beam seas and head seas have been recorded. In each case the center payload tray is found to experience attenuated heave accelerations compared with the two pontoon hulls. The reductions in surge and sway motion are, however, not evident. The associated spectra suggest that heaving motion of the center payload tray over a range of frequencies is attenuated by the suspension system. No attenuation is apparent in the surge and sway motions. The WAM-V dynamics is modeled as a three-body problem with the pontoons corresponding to bodies 1 and 2, and the central tray to body 3. Results of the analysis are compared with the sea trials.© 2013 ASME
Design of WDM Cross Connect Based on Interleaved AWG (IAWG) and a Phase Shifter Array

A general design rule for interleaved arrayed waveguide gratings (IAWGs) is derived. A 1timesN WDM switch that is based on a phase shifter array, which is sandwiched between two N-IAWGs, is systematically analyzed. A practical design example of a 1times4 nonblocking wavelength division multiplexing (WDM) switch is detailed to illustrate the design steps and the required phase assignment of each phase shifter for various output states. Based on the reciprocity principle, a simplified structure of the 1timesN WDM switch is proposed, which requires only one N-IAWG with total reflection implemented at the end of each phase shifter. This type of NtimesN WDM switch can be used as a fundamental building block to construct the nonblocking WDM all-optical switch that will be indispensable for future all-optical networks.
Tanshinone (Salviae miltiorrhizae Extract) Preparations Attenuate Aminoglycoside-Induced Free Radical Formation In Vitro and Ototoxicity In Vivo

Antioxidant therapy protects against aminoglycoside-induced ototoxicity in animal models. A clinically suitable antioxidant must not affect the therapeutic efficacy of aminoglycosides or exhibit any side effects of its own. In addition, the treatment should be inexpensive and convenient in order to be implemented in developing countries where the use of aminoglycosides is most common. Standardized Salviae miltiorrhizae extracts (Danshen) are used clinically in China and contain diterpene quinones and phenolic acids with antioxidant properties. We combined in vitro and in vivo approaches to investigate the effect of a clinically approved injectable Danshen solution on aminoglycoside-induced free radical generation and ototoxicity. In vitro, Danshen inhibited gentamicin-dependent lipid peroxidation (formation of conjugated dienes from arachidonic acid), as well as the gentamicin-catalyzed formation of superoxide (in a lucigenin-based chemiluminescence assay) and hydroxyl radicals (oxidation of N,N-dimethyl-p-nitrosoaniline). Danshen extracts were then administered to adult CBA mice receiving concurrent treatment with kanamycin (700 mg/kg of body weight twice daily for 15 days). Auditory threshold shifts induced by kanamycin (approximately 50 dB) were significantly attenuated. Danshen did not reduce the levels in serum or antibacterial efficacy of kanamycin. These results suggest that herbal medications may be a significantly underexplored source of antidotes for aminoglycoside ototoxicity. Such traditional medicines are widely used in many developing countries and could become an easily accepted and inexpensive protective therapy.
Non-native grasses alter evapotranspiration and energy balance in Great Basin sagebrush communities

Over the last century non-native plants have invaded sagebrush communities of the American West. The widespread transformation from native sagebrush to invasive grassland communities as a result of wildfire will likely alter key ecosystem processes in the Great Basin, including hydrology and energybalance. To determine how this invasion may be disrupting ecosystem function, we coupled measurements of evapotranspiration (ET) and energy fluxes using the Bowen ratio-energy balance method with measurements of normalized difference vegetation index (NDVI) and plant cover in native sagebrush and adjacent post-fire bunchgrass communities in the northern Great Basin Desert over the growing season of 2003. Soil heat flux and soil temperatures were generally greater and sensible heat flux and net radiation were lower in the post-fire community compared to sagebrush. These differences increased through the summer. The post-fire community had greater ET than sagebrush in early May, likely driven by relatively high volumetric soil moisture (>20%) and greater transpiration by the developing vegetation. In June and July, ET was correlated with surface soil moisture (top 20 cm) in both communities. During late May and June, surface soil moisture was greater in the sagebrush; however, there was no difference after mid-June when soil moisture declined below 10%. By disrupting surfaceatmosphere exchange in the early growing season, conversion of native sagebrush to post-fire invasive communities may disrupt hydrologic patterns in this semi-arid ecosystem. # 2006 Elsevier B.V. All rights reserved.
Evidence for a clade-specific temporal and spatial separation in ribulose bisphosphate carboxylase gene expression in phytoplankton populations off Cape Hatteras and Bermuda

The factors affecting the regulation of photosynthetic carbon fixation in diverse phytoplankton populations are not yet understood. To this end, we have measured the expression of the gene (rbcL) for the major carbon fixation enzyme, ribulose-1,5-bisphosphate carboxylase/oxygenase, in coastal phytoplankton populations off Cape Hatteras and in oligotrophic oceanic picoplankton near Bermuda. Using gene probes specific for the cyanobacterial/chlorophytic clade and the chromophytic clade (diatoms, chrysophytes, prymnesiophytes, and others) of Form I rbcL genes (‘‘cyano’’ and ‘‘chromo’’ probes, respectively), we have measured rbcL messenger ribonucleic acid (mRNA) levels in size-fractionated coastal waters, in a decktop diel incubator and a Lagrangian drifter study, and in vertical profiles in stratified, oligotrophic ocean water. In coastal waters influenced by estuarine plumes, an equal distribution of carbon fixation between the picoplankton and the micro/nannoplankton occurred, with cyano rbcL mRNA coinciding with Synechococcuscounts in the ,1-mm fraction, with the majority of the chromo rbcL mRNA expression occurring in the larger sized phytoplankton fraction. In profiles of oligotrophic oceanic waters, the cyano rbcL mRNA was found in the upper water column (;50-m depth) and coincided with peaks in Synechococcus counts. The chromo rbcL mRNA was concentrated at the subsurface chlorophyll a (Chl a) maximum (;85 m) and corresponded to red-fluorescing cell counts, thought to be picoeucaryotes and diatoms. Photosynthetic carbon fixation and RUBISCO enzyme activity encompassed both cyano and chromo rbcL mRNA peaks, suggesting a near equal contribution to carbon fixation in the water column by these two phytoplankton clades. Both decktop diel incubator studies and a Lagrangian drifter study in coastal waters indicated cyano rbcL transcription in the morning and chromophytic rbcL transcription in the late afternoon/early evening. Thus, the two major clades of RUBISCOcontaining phytoplankton occupy separate niches in time, space, and cell size in the waters off Cape Hatteras. The factors determining such clade-specific niches may include efficiency of nutrient utilization, differences in relative carboxylase/oxygenase activity (t values) of cyano (Form IB) and chromophytic (Form ID) RUBISCOs, and differences in pigment composition/adaptation to light regimes. Additionally, we propose that chromo rbcL mRNA may be indicative of new production, whereas cyano rbcL mRNA correlates with recycled production in stratified, oligotrophic oceanic environments.
Numerical and Experimental Study of Non -Destructive Detection of Thermal Tile System Debonding Using Short - Pulse Laser

An experimental and numerical study is performed to analyze short pulse laser propagation through TPS tile samples with and without debonds. Short pulse laser probing techniques has distinct advanta ges over conventional very long pulse width o r CW lasers primarily due to the additional information conveyed about the medium by the temporal variation of the observed signal. Both the scattered temporal transmitted and reflected optical signals are measured experimentally using a streak camera for samples irradiated with a short pulse laser source. Parametric study involving number of debonds and size s are performed. The temporal and spatial profiles of the scattered optical signals are compared with the numerical modeling results obtained by solvin g the transient radiative transport equation using discrete ordinates technique. Good agreement between the two illustrates the promise of this technique for detecting TPS debonding.
Single monolayer nanocrystal LED on probe tip for near-field molecular imaging and patterning

We report a novel light emitting nano-diode structure consisting of a single monolayer of CdSe nanocrystals deposited on a scanning probe tip for near-field scanning optical microscopy (NSOM). P-doped silicon which forms the probe body was utilized as an anode of the LED. A Langmuir-Blodgett (LB) trough was used to deposit on-probe a monolayer of nanocrystals (5-10 nm thickness), which were then examined with a SEM/TEM to show uniform deposition, and a fluorescent microscope to demonstrate light emitting properties. Both photoluminescent and electroluminescent emissions were observed from the fabricated probe with monolayer LED. Preliminary imaging and patterning using functional light emitting silicon probes were demonstrated in a standard NSOM setup. Resolutions of 50 nm and 400 nm were acquired for topographic and optical imaging, respectively.
Crystalline human eye lens’ response to stochastic light

We present the first account (to our knowledge) of interaction between stochastic light and the crystalline human eye lens. In particular, the spectral density and the spectral degree of polarization of light focused by the crystalline lens onto the eye's back wall are examined. We find that the correlation properties of the incident light play the important role in the process of image formation by the eye and in its perception of polarization features of the incoming radiation.
Towards multi-site collaboration in tele-immersive environments

Tele-immersion is emerging as a new medium that creates 3D photorealistic, immersive, and interactive experience between geographically dispersed users. However, most existing tele-immersive systems can only support two-way collaboration. In this paper we propose a multi-layer framework and a new data dissemination protocol to support multi-site collaboration. The problem context is unique as multiple remote sites participate in an interactive tele-immersive session, where each site has multiple correlated 3D video streams to send (later referred as multi-stream/multi-site environments). The key challenge is to disseminate such large number of 3D live video streams among these sites subject to the bandwidth and latency constraints while satisfying QoS guarantees in visual quality. Among our findings is that the simple randomized algorithm outperforms many other static algorithms in the unique context. Moreover, the streams generated from one site have high semantic correlation, because often cameras at one site are shooting the same scene, only from different angles. We exploit the stream correlation in the multicast protocol to minimize the level of loss.
Development of Stable Small Quantum Dots for AMPA Receptor Tracking at Neuronal Synapses

AMPA receptors are important excitatory neurotransmitter receptors in the brain. Trafficking of AMPA receptors in and out of synapses affects synaptic plasticity. Quantum dots have been used as fluorescent probes for tracking diffusion of AMPA receptors. However, the size of commercially available quantum dots is ∼20 nm, likely limiting their ability of accessing the synaptic cleft which is ∼30 nm. Therefore, photo-stable fluorescent probes with smaller sizes are needed. In this study, we developed a new method for coating quantum dot cores to obtain stable quantum dots with diameters about 9 nm. Currently, we have successfully made small quantum dots with different emission wavelengths (527 nm, 615 nm, 620 nm and 655 nm), and functionalized them with streptavidin. Furthermore, we tested the small quantum dots on cultured neurons and found that all of them bind to AMPA receptors with high specificity. We found that the diffusion behavior of AMPA receptors labeled with our small quantum dots is different from that with commercial quantum dots, indicating that bigger quantum dots may have hindered the AMPA receptors' accessibility to the synaptic cleft. In addition, we identified micro-domains of approximately 100 nm x 100 nm where the AMPA receptors tend to bind and diffuse within these domains.
The velocity of shear fracture

The maximum velocity of fracture in an homogeneous isotropic elastic medium under pure shear stress and with an added compressive stress is computed by an extension of Yoffe's method. The maximum velocity of shear fracture is smaller than the velocity of transverse waves in the medium. It increases as Poisson's ratio increases and decreases as the compressive stress increases. The maximum velocity of pure shear fracture is higher than the velocity of pure tensile fracture in the same medium. For a medium with Poisson's ratio of 0.25 the former is 0.775 and the latter is 0.631 of the transverse wave velocity.
In-stent thrombosis after 68 months of implantation inspite of continuous dual antiplatelet therapy: a case report

Lately, there has been an increased incidence of late stent thrombosis; especially following Drug eluting stent (DES) implantation. Several factors are associated with an increased risk of stent thrombosis, including the procedure itself, patient and lesion characteristics, stent design, and premature cessation of anti-platelet drugs. We present a case of late stent thrombosis (LST) following DES implantation after a period of 68 months, making it the longest reported case of LST reported in the literature, despite the use of dual anti-platelet therapy.
Minimization algorithms for multiple-valued programmable logic arrays

The performance of various heuristic algorithms for minimizing realizations of multiple-valued functions by the charge-coupled device (CCD) and CMOS programmable logic arrays (PLAs) of H.G. Kerkhoff and J.T. Butler (1986) and J.G. Samson (1988), respectively, is analyzed. The functions realized by the PLAs are in sum-of products form, where the sum is ordinary addition truncated to the highest logic value and the product represents the MIN operation of functions of the input variables that are the interval literal operations. Three heuristics, proposed by G. Pomper and J.A. Armstrong (1981), P.W. Besslich (1986), and G.W. Dueck and D.M. Miller (1987), are compared over sets of random and random-symmetric functions. An exact minimization method that is a tree search using backtracking is described. A reduction in the search space is achieved by considering constrained implicant sets and by eliminating some implicants altogether. Even with this improvement, the time required for exact minimization is extremely high when compared to all three heuristics. The case involving only prime implicants is considered, and it is shown that such implicants have marginal value compared to constrained implicant sets. The basis of comparison is the average number of product terms. >
Thrombospondin-based antiangiogenic therapy

Thrombospondins (TSPs) are a family of extracellular matrix proteins that regulate tissue genesis and remodeling. TSP-1 plays a pivotal role in the regulation of both physiological and pathological angiogenesis. The inhibitory effects of TSP-1 on angiogenesis have been established in numerous experimental models. Among other TSP members, TSP-2 has equivalent domain structure as TSP-1 and shares most functions of TSP-1. The mechanisms by which TSP-1 and -2 inhibit angiogenesis can be broadly characterized as direct effects on vascular endothelial cells and indirect effects on the various angiogenic regulators. The fact that TSP-1 and -2 are potent endogenous angiogenic inhibitors has prompted studies to explore their therapeutic applications, and detailed understanding of the mechanisms of action of TSP-1 and -2 has facilitated the design of therapeutic strategies to optimize these activities. The therapeutic effects can be achieved by up-regulation of endogenous TSPs, or by the delivery of recombinant proteins or synthetic peptides that contain sequences from the angiogenic domain of TSP-1. In this article, we review the progress in thrombospondin-based antiangiogenic therapy and discuss the perspectives on the significant challenges that remain.
Making Taq DNA polymerase in the undergraduate biology laboratory

Abstract The polymerase chain reaction (PCR) is an important technique for biology students to learn. PCR utilizes DNA polymerases isolated from archaea or bacteria, like Thermus aquaticus (Taq), to amplify target DNA sequences. In this paper we describe lab activities where students clone the gene for, express, and purify Taq DNA polymerase and assay for its activity. These lab activities employ plasmids containing multiple components of the lac operon thereby giving students practical experience with a genetic regulatory system they learn about in the classroom. Taq DNA polymerase purification simply involves cell lysis, a heat incubation step, and centrifugation, with the resulting supernatant containing highly pure and active Taq DNA polymerase.
Man-made disaster and development: The case of Iraq

EnglishThe idea of disaster is usually associated with human suffering from natural events. However, human-made disasters caused by deliberate actions represent an equally important dimension of di...
Ultra-sensitive detection of protein thermal unfolding and refolding using near-zone microwaves

We use planar slot antennas proximal to proteins in solution to detect changes in conformation. The antennas are attached to fused-quartz or glass sample holders and the cuvette/antenna assembly is placed in the sample holder of an optical spectrophotomer (either UV/VIS or fluorescence polarization), allowing simultaneous dielectric and optical measurements. Return loss is recorded using a vector network analyzer. This system was used to study the equilibrium thermal unfolding and refolding of a small globular protein, as well as the binding of small hormones to a receptor. Good agreement between optical and microwave measurements was obtained for all systems studied. We show that microwave measurements can be made at protein concentrations as low as 0.3 ng/mL (19 pM), several orders of magnitude lower than that required for optical spectroscopy. The results from these experiments demonstrate that resonant slot antennas can be used to detect changes in protein conformation and the presence of microwave radiation does not perturb the system under study.
Decentralized Diagnosis of Event-Driven Systems for Safely Reacting to Failures

We introduce the notion of safe-codiagnosability, extending the notion of safe-diagnosability (Paoli and Lafortune, 2005) to the decentralized setting. For a system, a certain subbehavior is deemed safe (captured via a safety specification), and a further subbehavior is deemed nonfaulty (captured via a nonfault specification). Safe-codiagnosability requires that when the system executes a trace that is faulty, there exists at least one diagnoser that can detect this within bounded delay and also before the safety specification is violated. The above notion of safe-codiagnosability may also be viewed as an extension of the notion of codiagnosability (Qiu and Kumar, 2006), where the latter did not have any safety requirement. We show that safe-codiagnosability is equivalent to codiagnosability together with ldquozero-delay codiagnosabilityrdquo of ldquoboundary safe tracesrdquo. (A safe trace is a boundary safe trace if there exists a single-event extension that is unsafe.) We give an algorithm of polynomial complexity for verifying safe-codiagnosability. For a safe-codiagnosable system, the same methods as those proposed in (Qiu and Kumar, 2006) can be applied for offline synthesis of individual diagnosers, as well as for online diagnosis using them.
A NEW SYNDROME OF DYSMORPHOGENESIS: IMPERFORATE‐ANUS ASSOCIATED WITH POLY‐OLIGODACTYLY AND SKELETAL (MAINLY VERTEBRAL) ANOMALIES

Summary Nine patients having imperforate anus and hand malformations with or without vertebral anomalies have been presented. The similarity of the findings in these patients to those seen among the members of the luxoid group of mouse mutants, such as the dominant hemimelia (Dh) mutants has been emphasized. Similar cases reported in the literature have been briefly reviewed.
Decline in Global Solar Radiation with Increased Horizontal Visibility in Germany between 1964 and 1990

Abstract A statistically significant decrease in mean annual global solar radiation between 1964 and 1990 under completely overcast skies was found at five out of eight studied locations in Germany. A decrease of global solar radiation is also evident in partly cloudy conditions. The mean annual cloud cover fraction and sunshine duration did not significantly change, while the visually assessed mean annual horizontal visibility increased at six of the eight stations. The authors’ findings point to a decrease of the cloud transmissivity, which in turn could be explained by an increased frequency of multilevel cloudiness, changing cloud types, or by indirect aerosol effects on clouds. The decreasing trend of global solar radiation in clear skies was most expressed at high and intermediate solar zenith angles, whereas a slight increase of global radiation was found at low sun zenith angles. A decline of the diffuse component of the global radiation over time was also detected. It is shown that the observed c...
Individual Differences and Driver Response to Highway Intersections

Along the Nation's roadways one of the most dangerous environments is the intersection. Accident investigations suggest several individual driver characteristics that may be associated with increased risk at intersections. To analyze the relationships of a number of driver characteristics to driver behavior in a controlled setting a laboratory simulation of the roadway intersection was created. Seventy-two research participants, ranging in age from 18 to 74, were measured on a battery of performance tests, administered questionnaires related to health and driving history, and exposed to a video display of approaching intersections as driver responses were measured. Each participant viewed 14 intersections containing a variety of traffic control devices. During the driving simulation portion of the research workload was assessed using six variables chosen to reflect three response modes-performance, subjective, and physiological. A MANOVA conducted to analyze the 3 (age level) by 2 (gender) factorial desig...
In vivo role of the extracellular matrix during vascular repair

Neointimal hyperplasia, smooth muscle cell (SMC) proliferation, and extracellular matrix (ECM) synthesis invariably follow vascular injury. A number of biologic and rheologic factors have been identified that contribute to the random variability during the post-injury repair phase. Accumulation of ECM after arterial injury is an important event in the development of fibrocellular intimal thickening and is central to vascular remodeling. This response can be regarded as highly dynamic that not only determines the physical elastic properties of the vessel wall but also its cellular components via growth factors, cytokines, and metalloproteinases. It has been estimated in clinical and experimental models that at 3 months following injury, ECM comprises greater than 80% of the neointimal volume with less than 11% occupied by cellular (SMC, fibroblast, foam cells) constituents. This paper broadly highlights the important role of ECM during vascular injury and repair.