cssi/SciSciGPT-SciSciNet huggingface dataset:
Screening mammography and the "r" word.

New recommendations on screening for breast cancer have raised concerns about access to potentially lifesaving care. Dr. Robert Truog believes that for health care reform to progress with clarity, transparency, and honesty, we must discuss how, not whether, we should ration health care.
Children's Developing Intuitions about the Truth Conditions and Implications of Novel Generics versus Quantified Statements.

Generic statements express generalizations about categories and present a unique semantic profile that is distinct from quantified statements. This paper reports two studies examining the development of children's intuitions about the semantics of generics and how they differ from statements quantified by all, most, and some. Results reveal that, like adults, preschoolers (a) recognize that generics have flexible truth conditions and are capable of representing a wide range of prevalence levels; and (b) interpret novel generics as having near-universal prevalence implications. Results further show that by age 4, children are beginning to differentiate the meaning of generics and quantified statements; however, even 7- to 11-year-olds are not adultlike in their intuitions about the meaning of most-quantified statements. Overall, these studies suggest that by preschool, children interpret generics in much the same way that adults do; however, mastery of the semantics of quantified statements follows a more protracted course.
Workman-Reynolds freezing potential measurements between ice and dilute salt solutions for single ice crystal faces.

Workman-Reynolds freezing potentials have been measured for the first time across the interface between single crystals of ice 1h and dilute electrolyte solutions. The measured electric potential is a strictly nonequilibrium phenomenon and a function of the concentration of salt, freezing rate, orientation of the ice crystal, and time. When all these factors are controlled, the voltage is reproducible to the extent expected with ice growth experiments. Zero voltage is obtained with no growth or melting. For rapidly grown ice 1h basal plane in contact with a solution of 10-4 M NaCl the maximum voltage exceeds 30 V and decreases to zero at both high and low salt concentrations. These single-crystal experiments explain much of the data captured on this remarkable phenomenon since 1948.
Oil market share dynamics: A Markov chain analysis of consumer and producer adjustments

We develop an “optimal market share rule” model of cartel behavior which when applied to the OPEC cartel appears capable of explaining its stability and responses to changed market events. In particular, by attaching importance to market shares based approximately on costs, OPEC members can by maintaining optimal shares deter deviant member attempts to break cartel rules. After a thorough discussion of the theory, the model is tested empirically using a Markov probability model.
Heterochromatin, satellite DNA, and cell function. Structural DNA of eucaryotes may support and protect genes and aid in speciation.

With the assumption that a portion that comprises some 10 percent of the genomes in higher organisms cannot be without a raison d'etre, an extensive review led us to conclude that a certain amount of constitutive heterochromatin is essential in multicellular organisms at two levels of organization, chromosomal and nuclear. At the chromosomal level, constitutive heterochromatin is present around vital areas within the chromosomes. Around the centromeres, for example, heterochromatin is believed to confer protection and strength to the centromeric chromatin. Around secondary constrictions, heterochromatic blocks may ensure against evolutionary change of ribosomal cistrons by decreasing the frequency of crossing-over in these cistrons in meiosis and absorbing the effects of mutagenic agents. During meiosis heterochromatin may aid in the initial alignment of chromosomes prior to synapsis and may facilitate speciation by allowing chromosomal rearrangement and providing, through the species specificity of its DNA, barriers against cross-fertilization. At the nuclear level of organization, constitutive heterochromatin may help maintain the proper spatial relationships necessary for the efficient operation of the cell through the stages of mitosis and meiosis. In the unicellular procaryotes, the presence of a small amount of genetic information in one chromosome obviates the need for constitutive heterochromatin and a nuclear membrane. At higher levels of organization, with an increase in the size of the genome and with evolution of cellular and sexual differentiation, the need for compartmentalization and structural components in the nucleus became imminent. The portion of the genome that was concerned with synthesis of ribosomal RNA was enlarged and localized in specific chromosomes, and the centromere became part of each chromosome when the mitotic spindle was developed in evolution. Concomitant with these changes in the genome, repetitive sequences in the form of constitutive heterochromatin appeared, probably as a result of large-scale duplication. The repetitive DNA's were kept through natural selection because of their importance in preserving these vital regions and in maintaining the structural and functional integrity of the nucleus. The association of satellite (or highly repetitive) DNA with constitutive heterochromatin is understandable, since it stresses the importance of the structural rather than transcriptional roles of these entities. Nuclear satellite DNA's have one property in common despite their species specificity, namely heterochromatization. In this sense the apparent species specificity of satellite DNA may be the result of natural selection for duplicated short polynucleotide segments that are nontranscriptional and can be utilized in specific structural roles.
Sequence of the dodecapeptide from the NH 2 -terminus of rabbit muscle aldolase.

Abstract A peptide containing 12 amino acids has been isolated from the NH2 terminus of rabbit muscle aldolase. This peptide has the following amino acid sequence: (NH)Pro-His-Ser-His-Pro-Ala-Leu-Thr-Pro-Glu-Gln-Lys. The same NH2-terminal sequence was established for the α and β subunits.
A method for studying the interaction between lecithin: cholesterol acyltransferase and high density lipoproteins.

Abstract High density lipoproteins (HDL) are preferred substrates of the lecithin:cholesterol acyltransferase (LCAT) of blood plasma ( Glomset, 1968) . Although the basis of this preferential action of LCAT has not been clarified, presumably it depends on the formation of specific enzyme-substrate complexes. In this communication we describe a method for studying the formation of LCAT-HDL complexes that should prove useful not only in investigations of the mechanism of the acyltransferase reaction and the structure of HDL, but also in attempts to purify the enzyme. The method involves the formation of HDL-agarose, and the subsequent utilization of this insoluble, but apparently fully hydrated, product in studies of the interaction between HDL and LCAT. The experiments described below specifically concern the disruption of LCAT-HDL complexes by sodium taurocholate.
Foliar anatomy of Polygonum (Polygonaceae) : survey of epidermal and selected internal structures

Several anatomical characters in leaves were described, and their distribution determined, for 153 species ofPolygonum, mostly from herbarium specimens. Structures surveyed were epidermal (glandular and nonglandular trichomes, nodules, specialized parenchyma, stomatal apparatus) and internal (cavities, crystals, laticifer-like cells, nodules, subepidermal fibers). Cleared leaves were supplemented by resin-embedded sections and SEM preparations of selected species. No feature defines any taxonomic section, but some features occur only within one section. Laticifer-like cells, epidermal and internal nodules, resin cups, and unique epidermal and subepidermal cavities seem to be unknown elsewhere; other features (invaginated epidermal cells; enlarged crystal cells confined to paraveinal layer) are rare among angiosperms.
Optoelectronic plethysmography demonstrates abrogation of regional chest wall motion dysfunction in patients with pectus excavatum after Nuss repair

Abstract Purpose We previously demonstrated that patients with pectus excavatum (PE) have significantly decreased chest wall motion at the pectus defect compared with the rest of the chest vs unaffected individuals and use abdominal respiratory contributions to compensate for decreased upper chest wall motion. We hypothesize that PE repair will reverse chest wall motion dysfunction. Methods A prospective, institutional review board–approved study compared patients with PE before and after Nuss repair. Informed consent was obtained before motion analysis. Sixty-four patients with uncorrected PE ages 10 to 21 years underwent optoelectronic plethysmography analysis. Repeat analysis was performed in 42 patients 6 months postoperative (PO). Results Volume of the chest wall and its subdivisions were calculated. Total chest wall volume at rest was significantly increased after repair and in each thoracic compartment. PO patients developed increased midline marker excursion at the pectus defect and significantly decreased excursion at the level of the umbilicus. Conclusions Optoelectronic plethysmography kinematic analysis demonstrates that chest wall remodeling during Nuss repair results in increased thoracic volume. Chest wall motion dysfunction at the pectus defect is reversed after Nuss repair. Abdominal respiratory contributions are also markedly decreased. These findings may help to explain why patients with PE report an improvement in endurance after the Nuss procedure.
Homeless Families: Rebuilding Connections

Young families are the fastest-growing group of homeless people in the United States. Many women have suffered violations of physical and sexual abuse, reduced income through divorce, and discrimination in seeking housing. Families have been disconnected from their homes, an adequate income, health care services, schools, and their families. Selected literature is reviewed to promote understanding and advocacy nursing for this high-risk population.
Regulated Expression, Processing, and Secretion of Dog Mast Cell Dipeptidyl Peptidase I

Dipeptidyl peptidase I (DPPI) is a cysteine protease found predominantly in myelomonocytic cells, cytotoxic T-cells, and mast cells. Recent studies identify an intracellular role for mast cell-DPPI (MC-DPPI) by activating prochymase and protryptase to their mature forms. To better define MC-DPPI and to explore the possibility of extracellular roles, we purified MC-DPPI from mastocytoma cells. We found the dog C2 mastocytoma cell line to be the richest source yet described for DPPI, purifying up to 200 microg of enzyme per g of cells. Dog MC-DPPI has an Mr of approximately 175,000 and consists of four subunits, each composed of a propeptide, light chain, and heavy chain. The heavy chain is N-glycosylated and is heterogeneously processed to three different forms. NH2-terminal sequences of the heavy chain and propeptide are identical to those predicted from a cDNA clone we sequenced from a mastocytoma cDNA library. The dog cDNA-derived sequence is 86% identical to that of human DPPI. Dog mastocytoma cells incubated with 12-O-tetradecanoylphorbol-13-acetate increase expression of MC-DPPI mRNA. MC-DPPI maintains its activity for dipeptide substrates at a neutral to alkaline pH. Cells stimulated with ionophore or substance P secrete MC-DPPI in parallel with the granule-associated mediators tryptase and histamine. Thus, dog mastocytoma cells secrete DPPI that is active at the pH of extracellular fluids, suggesting that MC-DPPI may act outside the cell.
The Prolonged 1954 Midwestern U.S. Heat Wave: Impacts and Responses

AbstractThe highest recorded temperature in Illinois, 117°F (47.2°C) occurred on 14 July 1954 in East St. Louis. This occurred in the midst of a widespread, long-lasting heat wave covering significant parts of 11 states: from eastern Colorado through Kansas, Oklahoma, part of Texas, Missouri, and Arkansas, southern Illinois, and extending to western Tennessee, Alabama, Georgia, and parts of the Carolinas. According to historical climate data, this event ranked as one of the top five extended periods of heat in these states since 1895. No such prolonged heat wave has occurred in the Midwest since 1954. It stands to reason that since prolonged widespread heat waves have occurred in the last 100 years, there is a distinct possibility that they will occur again, and reviewing past impacts could help us plan for future events.This research examines the impacts of the heat felt in the Illinois, Missouri, and Kansas region, as well as the responses to the extreme temperatures. Impacts on human health and well-be...
Alcohol state-dependency and autonomic reactivity.

Fifty-two college students were randomly assigned to alcohol (A) or no alcohol (S) treatment groups to provide the drug sequences: SS, SA, AS, and AA, in a training and a 24-hr subsequent testing session. Alcohol by vodka mixed with a soft drink (soft drink alone as placebo) was given within a 1-hr period preceding the particular session. Behavioral measures consisted of word association recall (WA), picture identification, (PI), and time and errors in the completion of a finger maze (MT, ME). Physiological measures of electroencephalogram (EEG), heart rate (HR), finger pulse volume (FPV), skin resistance (SR), and respiration rate were recorded throughout the training and testing sessions. Behavioral state-dependent effects were noted for both word association and picture identification tasks, but not for maze time or errors. State-dependent effects were indicated for heart rate, finger pulse volume, and skin resistance. Multiple linear regression coefficients for WA and PI as dependent variables and HR, FPV, and SR as predictors were significant for WA for Ihe AS and SA groups combined, but not significant for the SS and AA groups combined. The results are discussed as they relate to arousal and drug stimulus hypotheses of state-dependency.
Porous B-doped graphene inspired by Fried-Ice for supercapacitors and metal-free catalysts

An easy and efficient approach inspired by the ‘Fried-Ice’ concept has been developed for the preparation of boron-doped graphene (B-G) with porous morphologies. The morphology, boron content, and specific surface area (SSA) of these porous graphenes could be well tuned by controlling the reaction temperature. Because of the steam etching effect, the as-prepared porous B-Gs have a high SSA of up to 622 m2 g−1. The porous B-doped graphene electrodes show promising performance in supercapacitors with a gravimetric capacitance of up to 281 F g−1. As metal-free electrocatalysts for the oxygen reduction reaction in alkaline medium, these electrodes facilitate the four-electron transfer process with high performances in limited current density and high onset potential (−0.12 V vs. SCE) that is close to that of the commercial Pt/C (40 wt%) and excellent tolerance to methanol and carbon monoxide.
Prions Affect the Appearance of Other Prions: The Story of [PIN+]

Prions are self-propagating protein conformations. Recent research brought insight into prion propagation, but how they first appear is unknown. We previously established that the yeast non-Mendelian trait [PIN(+)] is required for the de novo appearance of the [PSI(+)] prion. Here, we show that the presence of prions formed by Rnq1 or Ure2 is sufficient to make cells [PIN(+)]. Thus, [PIN(+)] can be caused by more than one prion. Furthermore, an unbiased functional screen for [PIN(+)] prions uncovered the known prion gene, URE2, the proposed prion gene, NEW1, and nine novel candidate prion genes all carrying prion domains. Importantly, the de novo appearance of Rnq1::GFP prion aggregates also requires the presence of other prions, suggesting the existence of a general mechanism by which the appearance of prions is enhanced by heterologous prion aggregates.
Synthesis of carbon-11-labeled piperidine ring of N-[ω-(6-methoxynaphthalen-1-yl)alkyl] derivatives as new selective PET σ1 receptor probes

Abstract Carbon-11-labeled piperidine ring of N-[ω-(6-methoxynaphthalen-1-yl)alkyl] derivatives were first designed and synthesized as new selective PET σ1 receptor probes. The target tracers were prepared by O-[11C]methylation of their corresponding phenolic hydroxyl precursors using [11C]CH3OTf under basic conditions and isolated by a simplified SPE method in 40–50% radiochemical yields based on [11C]CO2 and decay corrected to EOB. The overall synthesis time from EOB was 15–20 min, the radiochemical purity was >99%, and the specific activity at EOS was 111–185 GBq/μmol.
Tobacco smoke overload and ethnic, state, gender, and temporal cancer mortality disparities in Asian-Americans and Pacific Islander-Americans

Abstract Background. Asians and Pacific Islanders (APIs) are important populations nationally and globally. So we assessed cumulative tobacco smoke overexposure (smoke overload)/cancer mortality associations across states, ethnicities, years, and genders among API-Americans. Methods. Death rates were adjusted to the 2000 United States age standard, lung cancer death rates used as a smoke overload bio-index, and lung/non-lung cancer death rate linear regressions run. Cancer death rate smoking-attributable fractions (SAFs) are equal to 1 − estimated unexposed rate/observed rate. Results. The two lowest smoke overload and non-lung cancer death rates were in South Asian (Indo)-Californian females and males. The highest were in Korean-Californian males. Non-lung cancer death rates were tightly and steeply associated with smoke overload across ethnicity, state, year, or gender. Cancer death rate smoking-attributable fractions ranged from 0 in female and 6% in male Indo-Californians, to 39% in female and 57% in male API-Americans in 2002, to 71% in Korean-Californian and 69% in API Hawaiian males. Discussion. Many API American cancer death rate disparities across genders, ethnicities, states, or years can be explained by smoke overload disparities. Tobacco control may greatly reduce cancer death rates and disparities among API-Americans and, likely, others.
Light sources for fluorescein fluorophotometry.

Seven light sources were considered as excitation sources for ocular fluorescein fluorophotometry: tungsten, xenon flash, the continuous high pressure short arc lamps of xenon, xenon zinc iodide and mercury, and argon and He–Cd lasers. Each source was evaluated on the basis of its spectral match to the fluorescein absorption spectrum and dissimilarity to the ocular blue light hazard function. Light from the argon laser was found to be most suitable while light from the mercury arc and He–Cd laser was least. Each source was also evaluated on the basis of irradiance available at the cornea when used with a Zeiss slit lamp that had been converted to an ocular fluorophotometer.
The 1.6 A crystal structure of the AraC sugar-binding and dimerization domain complexed with D-fucose.

Abstract The crystal structure of the sugar-binding and dimerization domain of the Escherichia coli gene regulatory protein, AraC, has been determined in complex with the competitive inhibitor d -fucose at pH 5.5 to a resolution of 1.6 A. An in-depth analysis shows that the structural basis for AraC carbohydrate specificity arises from the precise arrangement of hydrogen bond-forming protein side-chains around the bound sugar molecule. van der Waals interactions also contribute to the epimeric and anomeric selectivity of the protein. The methyl group of d -fucose is accommodated by small side-chain movements in the sugar-binding site that result in a slight distortion in the positioning of the amino-terminal arm. A comparison of this structure with the 1.5 A structure of AraC complexed with l -arabinose at neutral pH surprisingly revealed very small structural changes between the two complexes. Based on solution data, we suspect that the low pH used to crystallize the fucose complex affected the structure, and speculate about the nature of the changes between pH 5.5 and neutral pH and their implications for gene regulation by AraC. A comparison with the structurally unrelated E. coli periplasmic sugar-binding proteins reveals that conserved features of carbohydrate recognition are present, despite a complete lack of structural similarity between the two classes of proteins, suggesting convergent evolution of carbohydrate binding.
THE EFFECT OF HEAT AND SHEAR ON THE VISCOELASTIC PROPERTIES OF SOY FLOUR DOUGH

This paper is concerned with the effect of heat and shear on the rheological properties of defatted soy dispersions and doughs of 30 to 60% flour by weight. Capillary and rotary rheometers (Rheometrics Mechanical Spectrometer) were used to heat doughs up to 75° C and shear them simultaneously. In one series of experiments using a modified Instron capillary rheometer the doughs were heated to several different temperatures and then sheared. The linear viscoelastic properties of the dough which were determined by means of a plate-plate rheometer were then compared to the fresh dough and those of a heated but nonsheared dough. In another experiment a cone-and-plate rheometer was used to heat and shear the dough. The linear viscoelastic response of the dough was used to monitor any changes as it was heated and sheared. It was observed that only in the higher moisture dispersions (i.e., moisture contents greater than 50%) were there any signs of an increase in rheological properties which might be associated with “cooking”. It was concluded that cooking of soy flour doughs most likely does not involve the formation of a permanent network formed by covalent chemical bonds. Hence, in extrusion cooking processes involving soy flour doughs, it may not be necessary to treat the rheological properties of the dough as a thermosetting system.
The quality of well-being in cystic fibrosis.

Traditional outcome measures in CF include PFTs, exercise tests, and several scoring systems that depend on pulmonary status and are largely subjective. The Quality of Well-being scale (QWB) is a widely used tool for measuring quality of life by three subscales: mobility, physical activity, and social activity, with points assigned within each subscale. The QWB has been shown to be valid in patients with COPD. We administered the QWB scale to 44 patients with CF, aged 7 to 36 years, and examined the relationship between QWB and PFTs, and in 15 patients the QWB vs exercise performance (peak VO 2 ) on a progressive cycle ergometer test. QWB was significantly correlated with each variable examined: QWB vs FEV 1 , r=0.5518 (p 2 , r=0.5778 (p (Chest 1989; 95:344-47) QWB = quality of well-being; SEP = Sickness Impact Profile
Ascorbate peroxidase. A prominent membrane protein in oilseed glyoxysomes.

The glyoxysomes of growing oilseed seedlings produce H2O2, a reactive oxygen species, during the [beta]-oxidation of lipids stored in the cotyledons. An expression library of dark-grown cotton (Gossypium hirsutm L.) cotyledons was screened with antibodies that recognized a 31-kD glyoxysomal membrane polypeptide. A full-length cDNA clone (1258 bp) was isolated that encodes a 32-kD subunit of ascorbate peroxidase (APX) with a single, putative membrane-spanning region near the C-terminal end of the polypeptide. Internal amino acid sequence analysis of the cotton 31-kD polypeptide verified that this clone encoded this protein. This enzyme, designated gmAPX, was immunocytochemically and enzymatically localized to the glyoxysomal membrane in cotton cotyledons. The activity of monodehydroascorbate reductase, a protein that reduces monodehydroascorbate to ascorbate with NADH, also was detected in these membranes. The co-localization of gmAPX and monodehydroascorbate reductase within the glyoxysomal membrane likely reflects an essential pathway for scavenging reactive oxygen species and also provides a mechanism to regenerate NAD+ for the continued operation of the glyoxylate cycle and [beta]-oxidation of fatty acids. Immunological cross-reactivity of 30- to 32-kD proteins in glyoxysomal membranes of cucumber, sunflower, castor bean, and cotton indicate that gmAPX is common among oilseed species.
Self and other in ethnicity and bureaucracy

Tambiah, S. J., Ethnic Fratricide and the Dismantling of Democracy. Chicago: University of Chicago Press. 1986. xi + 198 pp. including chapter references and Index. $17.95 cloth. Raby, Namika, Kachcheri Bureaucracy in Sri Lanka. Foreign and Comparative Studies/South Asia Series. No. 10. Maxwell School of Citizenship and Public Affairs. Syracuse University 1985. 188 pp. excluding chapter references and index. $12.00 paper.
MTree: an XML XPath graph index

This paper introduces the MTree index algorithm, a special purpose XML XPath index designed to meet the needs of the hierarchical XPath query language. With the increasing importance of XML, XPath, and XQuery, several methods have been proposed for creating XML structure indexes and many variants using relational technology have been proposed. This work proposes a new XML structure index, called MTree, which is designed to be optimal for traversing all XPath axes. The primary feature of MTree lies in its ability to provide the next subtree root node in document order, for all axes, to each context node in O(1). MTree is a special purpose XPath index structure that matches the special purpose query requirements for XPath. This approach is in contrast to other approaches that map the problem domain into general purpose index structures such as B-Tree that must reconstruct the XML tree from those structures for every query. MTree supports modification operations such as insert and delete. MTree has been implemented both in memory and on disk, and performance results using XMark benchmark data are presented showing up to two orders of magnitude improvement over other well-known implementations.
Prediction of room air motion by Reynolds-stress models

The test results are presented from three Reynolds-stress models (two isotropization of production models and a quasi-isotropic model) and the standard k — ϵ model for predicting typical airflow in a room. The flow patterns studied are natural convection, forced convection and mixed convection in a room and an impinging jet flow. Experimental data from the literature is used for validation. The results show that the computations and the experimental data are in agreement for the mean air velocities, but less satisfactory for the turbulent quantities. The performance of the three Reynolds-stress models is similar, they all predict anisotropic turbulence and secondary recirculation existing in a room airflow for which the k — ϵ model fails. However, the Reynolds-stress models require additional computing effort compared to the k — ϵ model.
Verification and Validation in NASA-CUIP LOX/Methane Injector Research Efforts

The NASA-CUIP program is supporting experimental and modeling/computational research efforts investigating wall heat flux characteristics of LOX/methane single-element injectors. A Verification and Validation (V&V) task has begun with the objective of quantifying the degree of accuracy of the models for wall heat flux distributions at specific sets of conditions. The V&V approach used is that being drafted as a standard by the ASME Performance Test Codes Committee, PTC 61: Verification and Validation in Computational Fluid Dynamics and Heat Transfer. The approach is based on well-established concepts from experimental uncertainty analysis. Initially the V&V and uncertainty estimation efforts will use data obtained previously in the same facility using oxygen/hydrogen in single-element injector testing. In this paper the V&V process, experimental facility, and computer code are described, and approaches to estimating the associated uncertainties are discussed.
SIGDOC: reviewing the history from a company perspective

SIGDOC is the Association for Computing Machinery's Special Interest Group (SIG) on the Design of Communication (DOC). Until 2003, SIGDOC focused on documentation for hardware and software. With the shift in focus from systems to computer documentation to the design of communication, SIGDOC has better positioned itself to emphasize the potentials, practices, and problems of multiple kinds of communication technologies, such as Web applications, user interfaces, and online and print documentation. SIGDOC focuses on the design of communication as it is taught, practiced, researched, and conceptualized in various fields, including technical communication, software engineering, information architecture, and usability, etc. The traditional SIGDOC members were likely to be teachers, researchers, and/or practitioners of computer documentation. Today, members of SIGDOC include information design professionals, educators, researchers, software engineers, Web designers, system developers, usability specialists, computer scientists, user interface designers, and information technology specialists. What is the next sustainable change on the Design of Communication?
DISPERSANT EFFECTIVENESS ON OIL SPILLS – EMPIRICAL CORRELATIONS

ABSTRACT When a dispersant is applied to an oil slick, its effectiveness in dispersing the spilled oil depends on various factors such as oil properties, wave mixing energy, temperature of both oil and water, and salinity of the water. Estuaries represent water with varying salinities. In this study three salinity values in the range of 10–34 ppt were investigated, representing potential salinities found in typical estuaries. Three oils were chosen to represent light refined oil, light crude oil and medium crude oil. Each oil was tested at three weathering levels to represent maximum, medium and zero weathering. Two dispersants were chosen for evaluation. A modified trypsinizing flask termed the ‘Baffled Flask’ was used for conducting the experimental runs. A full factorial experiment was conducted for each oil to investigate the effect of salinity (3 levels), temperature (6 levels), oil weathering (3 levels) and mixing energy (150, 200, and 250 rpm) on dispersant effectiveness. Each experiment was replic...
Isolation and characterization of rat ribosomal DNA clones

Four EcoRI fragments, which contain the transcribed portion of the rat rDNA repeat, have been isolated from a rat genome library cloned in lambda Charon 4A vector. Three of the fragments, 9.6, 6.7, and 4.5 kb, from clones lambda ChR-B4, lambda Nr-42, and lambda ChR-C4B9, contained part of the 5'-NTS, the 5'-ETS, 18S rDNA, ITS-1, 5.8S rDNA, 28S rDNA and approximately 3.5 kb of the 3'-NTS. Two EcoRI fragments, from clones lambda ChR-B4 and lambda ChR-B7E12, which coded for the 5'-NTS, the ETS, and most of the 18S rDNA, differed by 1 kb near the EcoRI site upstream of the 5' terminus of 18S rRNA. Restriction maps of the cloned DNA fragments were constructed by cleavage of the fragments with various restriction endonucleases and Southern hybridization with 18S, 5.8S, and 28S rRNA. These maps were confirmed and extended by subcloning several regions of the repeat in pBR322.
A convenient procedure for radiolabeling detritus with [14C]dimethylsulfate

Abstract A new procedure for radiolabeling detrital particles is presented. The methylating reagent dimethylsulfate is used, in radioactive form, to methylate hydroxyl groups present in detrital material collected in the field. The formed covalent bond is stable to autoclaving and extremes of pH. A preliminary analysis of the compounds methylated indicates that cellulose, chitin, and detritus are reactive with the reagent and readily radiolabeled.
Control of torsional modes in buildings under seismic excitation by adaptive base isolation

Passive base isolation systems used for the seismic response control of structures appear to be effective for small to medium strength earthquakes. Hybrid base isolation systems, which use an active system together with the passive base isolation system, may be used to control the response of structures subjected to larger ground motions created by larger magnitude earthquakes. A hybrid base isolation system which uses passive base isolation pads together with deflection inserting actuators is proposed. The system, placed between the foundation of the building and its superstructure, is used to minimize the forces imposed on the superstructure by the earthquake induced ground motion. A three dimensional structural model is developed to study the effectiveness of the adaptive base isolation system. The effect of the base isolation system on the flexible modes of the structure, including the torsional modes, is studied.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Plk1 depletion in nontransformed diploid cells activates the DNA-damage checkpoint

We previously reported that polo-like kinase 1 (Plk1) depletion by lentivirus-based RNA interference led to mitotic arrest and apoptosis in cancer cells, whereas normal diploid cell lines, hTERT-RPE1 and MCF10A, survived a similar level of depletion. To study homogeneous cell lines, we generated several Plk1-depleted hTERT-RPE1 and MCF10A clones that were derived from single cells depleted of Plk1. We found that in the long term, Plk1 depletion slowed proliferation of hTERT-RPE1 cells, apparently due to attenuated progression through S phase. These cells had altered morphology and were elongated compared with control. In contrast, MCF10A clones with mild levels of depletion showed no obvious phenotype. They appeared to have normal proliferation rates with no cell-cycle arrest. However, one MCF10A clone, which was severely depleted of Plk1, although viable, showed sporadic G2/M arrest and apoptosis. This MCF10A clone and all the hTERT-RPE1 clones displayed evidence of DNA-damage checkpoint activation. These data further support the interpretation that cancer cell lines have a much greater requirement for Plk1 than normal nontransformed diploid cells.
Molecular imaging by mass spectrometry — looking beyond classical histology

Imaging mass spectrometry (IMS) using matrix-assisted laser desorption ionization (MALDI) is a new and effective tool for molecular studies of complex biological samples such as tissue sections. As histological features remain intact throughout the analysis of a section, distribution maps of multiple analytes can be correlated with histological and clinical features. Spatial molecular arrangements can be assessed without the need for target-specific reagents, allowing the discovery of diagnostic and prognostic markers of different cancer types and enabling the determination of effective therapies.
Molecular Self Assembly: Solvent Guests Tune the Conformation of a Series of 2,6-Bis(2-anilinoethynyl)pyridine-Based Ureas.

The conformations of 2,6-bis(2-anilinoethynyl)pyridine-based urea receptors were studied by single crystal X-ray diffraction methods and revealed a rich conformational flexibility influenced by solvents. Whereas receptor L1 in DMSO prefers an “S” conformation, receptor L1 crystallizes in an “O” conformation from a DMSO/CH3OH binary solvent system, and a “W” conformation in the ternary solvent mixture DMSO/toluene/1,4-dioxane. In the case of L2, the molecule adopts an “S” conformation where water molecules are sandwiched between two molecules of L2 to form a dimer. Similar to L2, L3 also forms a dimer in which water molecules are sandwiched between L3 molecules, which are capped with two molecules of DMSO. Such a capping DMSO solvate is lacking in the case of L2. Taken together, these results demonstrate that the conformation of 2,6-bis(2-anilinoethynyl) pyridine-based urea receptors can be dramatically manipulated and tuned by the choice of crystallization solvents.
A realtime, memory efficient fingerprint verification system

Creating a biometric verification system in an energy and area constrained embedded environment is a challenging problem. Our paper describes a secure and efficient embedded fingerprint verification system for the "ThumbPod" embedded device, in which a complete real-time fingerprint recognition module, including both the minutiae extraction and the matching, works on a 50 MHz LEON-2 processor. As a result of the proposed SW/HW accelerations and memory optimizations, we achieve 65% reduction on the execution time and 67% reduction on the memory size against the reference implementation.
Closed-form expressions for modeling metal fill effects in interconnects

This paper demonstrates efficient methods to account for parasitic capacitance and eddy-current loss in on-chip interconnects due to square metal fill. The parasitic capacitance extraction is based on an effective 3D to 2D reduction approach while the eddy-current loss in in-plane and out-of-plane metal fill is estimated by an empirical formula developed over a wide range of dimensions and frequencies. The interconnect capacitance matches with 3D electrostatic simulation and measurement within 2.1%. The additional parasitic resistance due to eddy-current loss in metal fill matches within 10% with 3D quasi-magnetostatic simulation results.
Experimental studies of packing material stability

The Basalt Waste Isolation Project is conducting experiments to assess the stability of bentonite (sodium montmorillonite) and crushed basalt as waste package packing materials in a nuclear waste repository in basalt. The experiments are designed to identify changes in physical, chemical, and mineralogical properties that these materials could undergo in the repository environment. A series of bentonite dehydration experiments showed that after 1 year at 370/sup 0/C the clay's structural and swelling properties were preserved and only reversible dehydration occurred. At 440/sup 0/C, however, irreversible dehydration, collapse of the clay structure, and loss of swelling ability took place. Hydrothermal tests using bentonite, or an equal mixture of bentonite and basalt, along with synthetic groundwater, were also conducted. A bentonite + water experiment showed negligible structural alteration at 200/sup 0/C, although some iron enrichment of the clay occurred. At 300/sup 0/C, partial conversion of the montmorillonite to an iron- and potassium-rich smectite occurred, along with the formation of secondary quartz and albite. An experiment in the basalt + bentonite + water system at 150/sup 0/C resulted in partial etching of the basalt grains, but no detectable change in rock or clay mineralogy. At 300/sup 0/C, the basalt was strongly etched. Furthermore,more » iron- and potassium-rich smectite apparently replaced montmorillonite as the dominant clay, and secondary silica, zeolites, and minor feldspar were formed. These mineral assemblages are thought to be metastable at 300/sup 0/C, based on natural analogs. The kinetics and reaction paths of further transformations of packing materials are important areas for continued study. 10 references, 5 figures, 1 table.« less
Concurrent niche and neutral processes in the competition–colonization model of species coexistence

The importance of neutral dynamics is contentiously debated in the ecological literature. This debate focuses on neutral theory's assumption of fitness equivalency among individuals, which conflicts with stabilizing fitness that promotes coexistence through niche differentiation. I take advantage of competition–colonization trade-offs between species of aquatic micro-organisms (protozoans and rotifers) to show that equalizing and stabilizing mechanisms can operate simultaneously. Competition trials between species with similar colonization abilities were less likely to result in competitive exclusion than for species further apart. While the stabilizing mechanism (colonization differences) facilitates coexistence at large spatial scales, species with similar colonization abilities also exhibited local coexistence probably due to fitness similarities allowing weak stabilizing mechanisms to operate. These results suggest that neutral- and niche-based mechanisms of coexistence can simultaneously operate at differing temporal and spatial scales, and such a spatially explicit view of coexistence may be one way to reconcile niche and neutral dynamics.
Unidirectional operation of rectangular dielectric single-mode ring waveguide lasers

Since most fabricated waveguide lasers have approximately rectangular guiding cross sections, a qualitative description of propagation modes in such structures is given. Having developed the concept of the effective mode index to be used in Fresnel reflection coefficient calculations, the nonreciprocal mechanism due to the tilted output facet is described. This is followed by an estimate of the reciprocal-coupling loss introduced between the arms of the ring waveguide due to the tilted output facet. It is shown that with incidence angles approaching the critical angle, small tilt angles of the output facet can produce a drastic difference between the intensity reflectivities of the two oppositely sensed waves circulating in the ring, thus creating a nonreciprocal mechanism which favors unidirectional operation. >
Analysis of Vehicle Lane Changes for Determining Fastest Paths in the V2V2I ITS Architecture

In this paper I perform an analysis of vehicle lane changes and how they relate to fastest path determination. I converted live discrete loop detector data from the California Department of Transportation into continuous data to be utilized by vehicles in a vehicle-to-vehicle-to-infrastructure (V2V2I) intelligent transportation system (ITS) architecture. The continuous data was then used by FreeSim (http://www.freewaysimulator.com) to simulate live traffic conditions. As the time to traverse the edges in the transportation network were being constantly updated, additional vehicles were inserted into the network to determine travel times and fastest paths from a source node to a destination node. The output shows that faster and more accurate paths can be found if lane data is obtained rather than just summary data of loop detectors. Further, if vehicles can be routed along paths with optimal lane changes to decrease the total travel time, a savings of approximately 33% of the travel time can be experienced. It is also shown that the number of lane changes needed in the fastest path with regards to lanes is lower than the number of lane changes needed for other candidate fastest paths, and highways with less congestion require fewer lane changes.
Utilization of glucose and amino acids in insect cell cultures: Quantifying the metabolic flows within the primary pathways and medium development.

The current understanding of insect cell metabolism is very limited. In order to gain some insight into the growth and metabolism of insect cells Spodoptera frugiperda (Sf9), a comprehensive characterization of culture conditions for cells grown in the IPL-41 medium was made by measuring the amino acid composition of the growth medium and the cell extract, the macromolecular composition of the cells (DNA, RNA, and protein), medium concentrations of various metabolites and sugars, and the evolved CO(2). Since in the IPL-41-based serum-free medium all of the amino acids except cysteine are in great excess of what is needed by the cells for energy and protein production, a medium formulation with an osmolarity similar to the IPL-41 but with a lower amino acid content than IPL-41 was also developed. The new medium also lacks maltose and sucrose (contains only glucose), supported cell growth to a high cell density of 8 x 10(6) cells/mL. The cellular and energetic yields indicated that a tight coupling between the biosynthetic and energetic reactions was attained for cells grown in the new medium. Moreover, it was found that the intermittent feeding of glucose may not be required as the cell yield and growth rate were comparable whether the same total amount of glucose was provided intermittently or was included initially in the medium. The eventual cessation of growth in the new medium is believed to be due to the amino acid limitation because concentrations of both glutamine and glutamate were very low at the end of the growth phase. Thus, further optimization, which may include higher initial glutamine in the medium or its intermittent feeding, could lead to a further increase in the cell density. Finally, a stoichiometrically based analysis of metabolic reactions confirmed the operation of the key pathways and was used to quantify the distribution of metabolites among primary metabolic reactions. The quantitative flow values were used to highlight some key aspects of insect cell metabolism.
Phototransformation rate constants of PAHs associated with soot particles

Photodegradation is a key process governing the residence time and fate of polycyclic aromatic hydrocarbons (PAHs) in particles, both in the atmosphere and after deposition. We have measured photodegradation rate constants of PAHs in bulk deposits of soot particles illuminated with simulated sunlight. The photodegradation rate constants at the surface (k(p)(0)), the effective diffusion coefficients (D(eff)), and the light penetration depths (z(0.5)) for PAHs on soot layers of variable thickness were determined by fitting experimental data with a model of coupled photolysis and diffusion. The overall disappearance rates of irradiated low molecular weight PAHs (with 2-3 rings) on soot particles were influenced by fast photodegradation and fast diffusion kinetics, while those of high molecular weight PAHs (with 4 or more rings) were apparently controlled by either the combination of slow photodegradation and slow diffusion kinetics or by very slow diffusion kinetics alone. The value of z(0.5) is more sensitive to the soot layer thickness than the k(p)(0) value. As the thickness of the soot layer increases, the z(0.5) values increase, but the k(p)(0) values are almost constant. The effective diffusion coefficients calculated from dark experiments are generally higher than those from the model fitting method for illumination experiments. Due to the correlation between k(p)(0) and z(0.5) in thinner layers, D(eff) should be estimated by an independent method for better accuracy. Despite some limitations of the model used in this study, the fitted parameters were useful for describing empirical results of photodegradation of soot-associated PAHs.
Whiskers, hillocks, and film stress evolution in electroplated Sn and Sn-Cu films

The growth of surface defects on lead-free tin electroplated films is believed to be a stress relief phenomenon. These observed defects include hillocks and whiskers that grow spontaneously after deposition. Previous work has shown that it is possible to plate pure tin and observe only hillock growth. Whisker growth, however, is observed with the addition of copper contamination to the electrolyte. In this work, pure tin and tin-copper films of increasing copper content were electroplated on phosphor bronze substrates. The stresses associated with plating these films and the evolution of stress over time were measured using cantilever beam deflection. The density and morphologies of hillocks and whiskers were measured as a function of time and are related to cantilever beam stress measurements. Results show an increase in long-term stress with increasing copper content. An initial decrease in the plating stress over the first 24 to 48 hours and an increase in relaxation rate with copper amounts of less than 0.0018 mol / L in the electrolyte was also observed. A transition in film behavior observed in copper concentrations between 0.0018 and 0.0057 mol / L, as characterized by an increasing as- plated plating stress, decreasing relaxation rate, and the appearance of whiskers. A change in hillock appearance was also observed in these concentrations. Results support a growth model where a source feeds material into a defect while the ratio of incoming material to the rate of grain boundary movement determines the types of defects observed.