cssi/SciSciGPT-SciSciNet huggingface dataset:
Influence of misfit strain on {311} facet development in selective epitaxial growth of Si1−xGex/Si(100) grown by gas-source molecular beam epitaxy

Abstract Selective epitaxy of Si 1− x Ge x /Si(100) via gas-source molecular beam epitaxy was carried out to compare facet formations in Si 1− x Ge x to Si. A single {311} facet with a pronounced cusp at the intersection with the (100) surface was observed in large windows (25 μm). However, facet formations occurring within smaller windows (≤5 μm) show the development of {311}- and {111}- type facets. For the 1–2 μm features, no cusps were observed, and facet growth was initiated at an earlier stage of development, avoiding contact with the SiO 2 mask. While a 1400 A Si epilayer is expected to have a {311}/{111} ratio of much less than one (∼0.15), for the 1–2 μm windows, however, it is ∼2. The persistence of the {311}-type facet offers a faster reduction of the original (100) surface that facilitates the fabrication of a nanoscale template.
Climate effects of seasonally varying Biomass Burning emitted Carbonaceous Aerosols (BBCA)

Abstract. The climate impact of the seasonality of Biomass Burning emitted Carbonaceous Aerosols (BBCA) is studied using an aerosol-climate model coupled with a slab ocean model in a set of 60-year long simulations, driven by BBCA emission data with and without seasonal variation, respectively. The model run with seasonally varying emission of BBCA leads to an increase in the external mixture of carbonaceous aerosols as well as in the internal mixture of organic carbon and sulfate but a decrease in the internal mixture of black carbon and sulfate relative to those in the run with constant annual BBCA emissions, as a result of different strengths of source/sink processes. The differences in atmospheric direct radiative forcing (DRF) caused by BBCA seasonality are in phase with the differences in column concentrations of the external mixture of carbonaceous aerosols in space and time. In contrast, the differences in all-sky radiative forcing at the top of the atmosphere and at the earth's surface extend beyond the BBCA source regions due to climate feedback through cloud distribution and precipitation. The seasonality of biomass burning emissions uniquely affects the global distributions of convective clouds and precipitation, indicating that these emissions have an impact on atmospheric circulation. In addition, the climate response to the periodic climate forcing of BBCA is not limited to biomass burning seasons but dynamically extends into non-biomass burning seasons as well.
Partial nitritation of swine wastewater in view of its coupling with the anammox process

Partial nitritation (PN) of swine wastewater was investigated in a sequencing batch reactor (SBR) using a high-performance nitrifying sludge. Characteristics of the wastewater used were low content of biodegradable organic matter and a high alkalinity-to-ammonium ratio. The target oxidation of ammonium nitrogen (NH4+–N) to nitrite nitrogen (NO2-–N) was 57% (1.32 g NO2-–N g–1 NH4+–N), which corresponds with the reaction ratio of the anaerobic ammonium oxidation (anammox). This target was successfully achieved at 32°C by controlling the inflow rate and the corresponding nitrogen loading rate (NLR). An average NLR of 1.47 g NH4+–N L-1 d-1 was applied to the partial nitritation sequencing batch reactor during a period of 70 d. The nitrite production rate obtained was 0.91 g NO2-–N L-1 d-1. No nitrate was produced. The PN effluent contained 1.38 g NO2-–N g-1 NH4+–N, which was within 5% of the target ratio. Under steady composition of the wastewater, the pH was shown to be a good indicator of the PN process performance. Furthermore, in a second sequencing batch reactor, the anaerobic ammonium oxidation process was effectively applied to the PN effluent, attaining a nitrogen conversion rate of 0.36 g N L-1 d-1 (14.3 mg N g-1 volatile suspended solids h-1).
Elderly Care and Intrafamily Resource Allocation when Children Migrate.

This paper considers the intrafamily allocation of elderly care in the context of international migration where migrant children may be able to provide financial assistance to their parents but are unable to offer physical care. To investigate sibling interaction, I estimate best response functions for individual physical and financial contributions as a function of siblings’ contributions. After addressing the endogeneity of siblings’ contributions and selection into migration, I find evidence that siblings’ financial contributions function as strategic complements while time contributions operate as strategic substitutes. This suggests that contributions may be based on both strategic bequest and public good motivations.
Challenges of business media

The full integration of digital media as a commonly available data type for business applications causes a major transition in computing infrastructure and solution architectures. While many corporate uses of digital media can be handled with the current infrastructure, as the amount and file size of the digital media grows, more than simple capacity improvements need to be implemented. The business needs for media are concrete; the problems we need to address are real. Our community needs to find real solutions too, for high-level semantic analysis, provisioning and management of mixed-media information, and distribution and delivery of media data to satisfy requirements dictated by business scenarios. The paper describe a few scenarios that show how corporations are using digital media to enhance their employee and customer communications, improve the effectiveness and efficiency of business processes, and create new business and revenue opportunities.
Displacement of Full-Timers by Part-Timers--A Model for Projection.

Abstract This article deals with the question of whether part-timers are displacing full-timers in academe. Using a CES production function and unique data from a national AAUP survey of 632 academic institutions, the authors project the size and the composition of the academic labor force for Ph.D.-granting universities and B.A.- and M.A.-granting colleges through 1987. The estimates are provided under three assumptions regarding what happens to the full-time and part-time labor force. In the process, information is generated on the relative compensation of the two faculty groups. In all three cases large gains are made in the number of part-time positions, while the number of full-time positions declines. The analysis suggests that serious errors can be introduced into models designed to forecast the demand for academicians if the tendency to substitute part-timers for full-timers is not taken into account.
Mechanism of the chloroperoxidase-catalyzed bromination of tyrosine

Abstract Free molecular Br2 was the intermediate formed in the bromide-dependent chloroperoxidase reaction. CPO was deactivated by free Br2 molecules associated with the destruction of its heme structure. The tyrosine bromination reaction was a nonenzymic chemical reaction between free molecular Br2 and tyrosine.
Fracture transitions in iron: Strain rate and environmental effects

A number of recent mechanical property studies have sought to validate atomistic and multiscale models with matching experimental volumes. One such property is the ductile-brittle transition temperature (DBTT). Currently no model exists that incorporates both external and internal variables in an analytical model to address both length scales and environment. Using thermally activated parameters for dislocation plasticity, the present study attempts a small piece of this. With activation energy and activation volumes previously determined for single and polycrystalline Fe-3% Si, predictions of DBTT both with and without atmospheric hydrogen are made. These are compared with standard fracture toughness measurements similarly for samples both with and without atmospheric hydrogen. In the hydrogen-free samples, average strain rate varied by four orders of magnitude. DBTT shifts are experimentally found and predicted to increase 100 K or more with either increasing strain rate or exposure to hydrogen.
Clinical and Pathologic Features Influencing Survival in Patients Undergoing Pancreaticoduodenectomy for Pancreatic Adenocarcinoma

Objective The aim of the study was to determine the clinicopathological features that influence survival in patients with resected pancreatic ductal adenocarcinoma (PDA).
Ca2+ homeostasis in sealed t-tubules of mouse ventricular myocytes

We have recently shown that in mouse ventricular myocytes, t-tubules can be quickly and tightly sealed during the resolution of hyposmotic shock of physiologically relevant magnitude. Sealing of t-tubules is associated with trapping extracellular solution inside the myocytes but the ionic homeostasis of sealed t-tubules and the consequences of potential transtubular ion fluxes remain unknown. In this study we investigated the dynamics of Ca(2+) movements associated with sealing of t-tubules. The data show that under normal conditions sealed t-tubules contain Ca(2+) at concentrations below 100μM. However, blockade of voltage-dependent Ca(2+) channels with 10μM nicardipine, or increasing extracellular concentration of K(+) from 5.4mM to 20mM led to several fold increase in concentration of t-tubular Ca(2+). Alternatively, the release of Ca(2+) from sarcoplasmic reticulum using 10mM caffeine led to the restoration of t-tubular Ca(2+) towards extracellular levels within few seconds. Sealing of t-tubules in the presence of extracellular 1.5mM Ca(2+) and 5.4mM extracellular K(+) led to occasional and sporadic intracellular Ca(2+) transients. In contrast, sealing of t-tubules in the presence of 10mM caffeine was characterized by a significant long lasting increase in intracellular Ca(2+). The effect was completely abolished in the absence of extracellular Ca(2+) and significantly reduced in pre-detubulated myocytes but was essentially preserved in the presence of mitochondrial decoupler dinitrophenol. This study shows that sealed t-tubules are capable of highly regulated transport of Ca(2+) and present a major route for Ca(2+) influx into the cytosol during sealing process.
The angiography program at Stanford

Abstract A program is underway at the Stanford Synchrotron Radiation Laboratory to evaluate at minimally invasive method of visualizing the coronary arteries in man using synchrotron radiation. The design of an X-ray imaging system to accomodate a newly-available X-ray beam 12.3 cm in width is described. The system performance as revealed with test images of phantoms and excised hearts is indicated, and the system components to be tested before clinical studies can begin are identified.
Interconnected ring networks: a performance study

The authors investigate the performance of multiple ring networks interconnected via bridges to a backbone ring. The networks use the IEEE 802.5 protocol. The model characterizes the behavior of the IEEE 802.2 protocol used at the logical link control layer. The primary performance measures are throughput and delay. The network carries only interring traffic. The model considers homogeneous traffic environments. It is shown that the protocol throughput is critically dependent on the window size and the buffer size at the intervening bridges. >
Selecting neonatal ethics.

Abstract Nontreatment of handicapped newborns has disturbed American society, prompting heated debate and new attempts by government at regulation. Robert Weir's new book reviews the elements of this controversy as argued by concerned doctors, lawyers and ethicists. Unfortunately, we do not know the magnitude or scope of the problem. We know little about how often or under what circumstances physicians practice nontreatment. In discussing the issues, Weir and others have paid inadequate attention to medical uncertainty. The inability to accurately predict outcome makes clinical judgment harder than most philosophers and others acknowledge. Many legal arguments are outdated. The concept of personhood Weir and ethicists invoke confounds decision making. Complex or uncertain medicomoral dilemmas will not be resolved more easily by ethics committees. This procedural solution to a substantive quandry creates new problems. More attention must be paid to patients' current and future suffering when deciding whether to treat severely handicapped infants.
XPORT: extensible profile-driven overlay routing trees

XPORT is a profile-driven distributed data collection and dissemination system that supports an extensible set of data types, profiles, and optimization metrics. XPORT efficiently builds a generic tree-based overlay network, which can be customized per application using a small number of methods that encapsulate application-specific data-profile matching, aggregation, and optimization logic. The clean separation between the "plumbing" and "application" enables XPORT to uniformly and easily support disparate dissemination-based applications such as content-based feed dissemination and application-level multicast. We propose to demonstrate the basic XPORT system, featuring its extensible optimization framework that facilitates easy specification of a wide range of useful performance goals and a continuous, adaptive optimization model to achieve these goals under changing network and application conditions. We will use two different underlying applications, an RSS feed dissemination application and a multiplayer network game, along with visual system-monitoring tools to illustrate the extensibility and the operational aspects of XPORT.
The Determination of Thallium in Urine

Abstract A variation of the triphenylmethane dye method for the determination of thallium has been modified to be suitable for analysis of urine samples in a small laboratory. Thallium is oxidized to the thallic state by bromine water, and is reacted with methyl violet for the colorimetric measurement. A maximum of 200 μg thallium per liter was found in the urine of 21 exposed individuals. Urine of unexposed persons showed virtually no thallium.
Introduction: Institutional Repositories: Current State and Future

Institutional repositories (IRs) currently exist in a rapidly shifting landscape without a clear consensus on their role in the academic environment. Low self-archiving rates have dampened hopes that IRs would have an impact on scholarly publishing models. Preservation programs, a stated goal of many IRs, are often not well established. In many cases, IRs are not part of a larger vision for services the library can provide to the institution, but are isolated projects without a strong base of support. Institutions are beginning to explore the role of IRs in the collection of materials like data sets. Given this environment, where will IRs be in the next five or ten years? This issue of Library Trends contains an impressive slate of articles from prominent practitioners and researchers in the field, who offer a range of perspectives on the current state of IRs in academic institutions and reflections on their future.
Exploring Motivations to Adopt

This study used National Survey of Adoptive Parents (NSAP) data to explore adoptive parent motivations. Examination of adoption motivation is important as it relates to recruitment of adoptive families for children needing homes. Findings show that families using the three main types of adoption—foster care, private domestic, and international—have somewhat similar motivations for adopting. Infertile couples are found within each adoption type and are happy with their choice. While many families adopting more than one child choose the same adoption type for each adoption, many families do not, choosing to adopt their children through different means.
Psychological Perspectives on ‘Acute on Chronic’ Trauma in Children: Implications of the 2010 Earthquake in Haiti

The 2010 earthquakes in Haiti initiated crises for one of the world's poorest nations. This transpired amidst pervasive, pre-disaster hardships, with the resulting situation described as ‘acute on chronic’ trauma exposure. The current paper provides a description of a dynamic model focused on three factors of consideration for similar crises: cultural context, unfolding traumatic events and developmental processes. Knowledge from developmental psychology can inform humanitarian aid efforts to effectively address the unique needs of children. Recommendations are offered for research, clinical work and policy related to the mental health needs of children where ‘acute on chronic’ conditions exist.
On the deformation behavior of the intermetallic compound AgMg

Abstract The stored energy, electrical resistivity and hardness of alloys within the homogeneity range of the compound AgMg have been measured as functions of strain in torsion at two temperatures. The stored energy and resistivity increased linearly with strain at 25°C, but reached plateaus on deformation at 165°C. At a given strain, the stored energy in the two non stoichiometnc alloys investigated was greater than that in the stoichiometric alloy; similarly, the change in resistivity was greater in the one nonstoichiometric alloy investigated than in the stoichiometric alloy The stored energy in the AgMg alloys deformed at 25°C is appreciably larger than any published value of the stored energy in metals and alloys deformed to the same strain at room temperature. The magnitudes of the stored energy and of the changes in resistivity suggest that the major effect of deformation at 25°C is the destruction of order At a given strain, the destruction of order appears to be greater in the non-stoichiometric alloys than in the stoichiometric alloy, probably because the pairs of dislocations comprising the superdislocations are more widely spaced in the former than m the latter. The attainment of plateaus in the stored energy and electrical resistivity as functions of strain at 165°C is attributed to vacancy promoted ordering occurring simultaneously with the mechanical destruction of order
Reaction of polyaniline with NMP at elevated temperatures

Heating a dilute solution of polyaniline emeraldine base in 1-methyl-2 pyrrolidinone under nitrogen at elevated temperatures resulted in the reduction of PANI to its leucoemeraldine state. The product was identified by infra-red, ultraviolet-visible, and X-ray photoelectron spectroscopy, and characterized by cyclic voltammetry and gel permeation chromatography.
West Nile virus infection modulates human brain microvascular endothelial cells tight junction proteins and cell adhesion molecules: Transmigration across the in vitro blood-brain barrier

Neurological complications such as inflammation, failure of the blood-brain barrier (BBB), and neuronal death contribute to the mortality and morbidity associated with WNV-induced meningitis. Compromised BBB indicates the ability of the virus to gain entry into the CNS via the BBB, however, the underlying mechanisms, and the specific cell types associated with WNV-CNS trafficking are not well understood. Brain microvascular endothelial cells, the main component of the BBB, represent a barrier to virus dissemination into the CNS and could play key role in WNV spread via hematogenous route. To investigate WNV entry into the CNS, we infected primary human brain microvascular endothelial (HBMVE) cells with the neurovirulent strain of WNV (NY99) and examined WNV replication kinetics together with the changes in the expressions of key tight junction proteins (TJP) and cell adhesion molecules (CAM). WNV infection of HBMVE cells was productive as analyzed by plaque assay and qRT-PCR, and did not induce cytopathic effect. Increased mRNA and protein expressions of TJP (claudin-1) and CAM (vascular cell adhesion molecule and E-selectin) were observed at days 2 and 3 after infection, respectively, which coincided with the peak in WNV replication. Further, using an in vitro BBB model comprised of HBMVE cells, we demonstrate that cell-free WNV can cross the BBB, without compromising the BBB integrity. These data suggest that infection of HBMVE cells can facilitate entry of cell-free virus into the CNS without disturbing the BBB, and increased CAM may assist in the trafficking of WNV-infected immune cells into the CNS, via 'Trojan horse' mechanism, thereby contributing to WNV dissemination in the CNS and associated pathology.
Integrating inter- & intra-site analyses of Epipalaeolithic faunal assemblages from Israel

Inter- and intra-site variability in faunal assemblages from Epipalaeolithic sites in the southern Levant are investigated to identify broad patterns of human hunting efficiency and specific human activities at individual sites. The examination of eleven assemblages from the Mediterranean phytogeographic zone of Israel indicates a decline in human hunting efficiency across the Epipalaeolithic period. This decline is part of an intensified hunting strategy driven by human-induced resource depression of high-ranked large game taxa (ungulates). More detailed analyses at the site level indicate distinct variation in the use of fauna within individual archaeological sites. At Hilazon Tachtit taxonomic representation differs substantially among features in the cave. The differential deposition of fauna reflects specific burial customs including the selection of particular body parts and taxa as grave inclusions and consumption events. At Hayonim Cave uneven body part representation reflects variation in the fun...
Comment on "absence of cooling in New Zealand and the adjacent ocean during the Younger Dryas chronozone"

Barrows et al. (Reports, 5 October 2007, p. 86) presented cosmogenic exposure dates and data from an ocean sediment core that challenge evidence for glacier advance in New Zealand during the Younger Dryas event. We use modeling of geomorphic processes to argue that their cosmogenic exposure dates are inconclusive.
Structural operational semantics for weak bisimulations

In this study, we present rule formats for four main notions of bisimulation with silent moves. Weak bisimulation is a congruence for any process algebra defined by WB cool rules; we have similar results for rooted weak bisimulation (Milner''s ``observational equivalence''''), branching bisimulation, and rooted branching bisimulation. The theorems stating that, say, observational equivalence is an appropriate notion of equality for CCS are corollaries of the results of this paper. We also give sufficient conditions under which equational axiom systems can be generated from operational rules. Indeed, many equational axiom systems appearing in the literature are instances of this general theory.
The shortest and the K‐shortest routes as assignment problems

The problem of finding a shortest route in a network with unrestricted costs is approached through solving an assignment problem associated to the network. The upper bound on the number of elementary calculations required for the solution is 0(m3). However, in most cases, the actual number of computations is considerably less and depends on different network characteristics than Dynamic Programming algorithms do. In examples of networks generated stochastically, this number was below 0(m2.5). A parametric analysis is presented. It is shown that if after a shortest route is determined, the costs on all arcs incident into or out of a node are modified in any form, at most 0(m2) elementary calculations will determine a new optimal solution. This feature, shared by Dynamic Programming algorithms only for cases where all cost decrease, can be applied to problems such as the determination of the K-shortest routes and the K-smallest assignments, leading to upper bounds of 0(Km3) in both cases.
A fluorinated ruthenium porphyrin as a potential photodynamic therapy agent: synthesis, characterization, DNA binding, and melanoma cell studies.

When the new porphyrin 5,10-(4-pyridyl)-15,20-(pentafluorophenyl)porphyrin is reacted with 2 equiv of Ru(bipy)2Cl2 (where bipy = 2,2′-bipyridine) formation of the target ruthenated porphyrin is achieved with 40% yield. Strong electronic transitions are observed in the visible region of the spectrum associated with the porphyrin Soret and four Q-bands. A shoulder at slightly higher energy than the Soret band is attributed to the Ru(dπ) to bipy(π*) metal to ligand charge transfer (MLCT) band. The bipyridyl π to π* transition occurs at 295 nm. Cyclic voltammetry experiments reveal two single-electron redox couples in the cathodic region at E1/2 = −0.80 and −1.18 V vs Ag/AgCl associated with the porphyrin. Two overlapping redox couples at E1/2 = 0.83 V vs Ag/AgCl due to the RuIII/II centers is also observed. DNA titrations using calf thymus (CT) DNA and the ruthenium porphyrin give a Kb = 7.6 × 105 M−1 indicating a strong interaction between complex and DNA. When aqueous solutions of supercoiled DNA and ruthe...
The Comparative Politics of Women's Movements

The comparative study of women's movements is developing within the political science subfield of women and politics, largely by drawing on concepts and findings from several disciplines. From political science it borrows theories of the state, political development, democracy, and democratization. Sociology offers insights on social movements and the gendered nature of societies. Women's studies scholarship enables us to understand systematic gendered arrangements of power and privilege, including those fragmented or reinforced by class, race, sexuality, and ethnicity. The subfield of women and politics contributes both feminist theoretical insights and scholarship on elected women, female leaders, and women's policy preferences; these contributions inform comparative research on women's movements.Karen Beckwith is a professor of political science at the College of Wooster (kbeckwith@wooster.edu). She is coeditor, with Lee Ann Banaszak and Dieter Rucht, of Women's Movements Facing the Reconfigured State and author of American Women and Political Participation. Beckwith is the founding editor, with Lisa Baldez, of Politics & Gender, the journal of the Women and Politics Research Section of the American Political Science Association. The author thanks Jeff Lantis and Kent Kille for extensive comments on earlier versions of this article.
Auto-segmentation of low-risk clinical target volume for head and neck radiation therapy

Abstract Purpose To investigate atlas-based auto-segmentation methods to improve the quality of the delineation of low-risk clinical target volumes (CTVs) of unilateral tonsil cancers. Method and Materials Sixteen patients received intensity modulated radiation therapy for left tonsil tumors. These patients were treated by a total of 8 oncologists, who delineated all contours manually on the planning CT image. We chose 6 of the patients as atlas cases and used atlas-based auto-segmentation to map each the atlas CTV to the other 10 patients (test patients). For each test patient, the final contour was produced by combining the 6 individual segmentations from the atlases using the simultaneous truth and performance level estimation algorithm. In addition, for each test patient, we identified a single atlas that produced deformed contours best matching the physician's manual contours. The auto-segmented contours were compared with the physician's manual contours using the slice-wise Hausdorff distance (HD), the slice-wise Dice similarity coefficient (DSC), and a total volume overlap index. Results No single atlas consistently produced good results for all 10 test cases. The multiatlas segmentation achieved a good agreement between auto-segmented contours and manual contours, with a median slice-wise HD of 7.4 ± 1.0 mm, median slice-wise DSC of 80.2% ± 5.9%, and total volume overlap of 77.8% ± 3.3% over the 10 test cases. For radiation oncologists who contoured both the test case and one of the atlas cases, the best atlas for a test case had almost always been contoured by the oncologist who had contoured that test case, indicating that individual physician's practice dominated in target delineation and was an important factor in optimal atlas selection. Conclusions Multiatlas segmentation may improve the quality of CTV delineation in clinical practice for unilateral tonsil cancers. We also showed that individual physician's practice was an important factor in selecting the optimal atlas for atlas-based auto-segmentation.
An application of minimax analysis to robust optimal control of molecular dynamics

Recent theoretical research has shown that a molecule can be manipulated and controlled by an optical field designed through optimal control theory. In practice, a number of disturbances/uncertainties arise, e.g., in the laboratory generated control field, in the molecular Hamiltonian, or in the interaction term (i.e., the dipole moment). It is, therefore, important to design an optimal control field which is robust to such disturbances. In this paper, we apply minimax analysis to design optimal control fields in the presence of disturbances having finite magnitude. The minimax analysis seeks the best control field in the presence of the worst disturbance of bounded magnitude, thus, the minimax solution gives a conservative estimate of the extent to which a physical objective can be achieved under the possed disturbances. As an example, we consider a diatomic molecule modeled as a Morse oscillator. The control objective is to achieve either selective excitation of a particular energy state or to transform an initial wave packet to an arbitrary nonstationary wave packet, in the presence of the three aforementioned disturbances. For the former objective, the results for the bounded worst disturbances and robust optimal control fields are similar to that of previous perturbation calculations. For the second objective, however, the results significantly differ from analogous perturbation calculations. Under certain severe conditions useful minimax solutions may be difficult to find or simply do not exist.
Approximate Bayes model selection procedures for Gibbs-Markov random fields

For applications in texture synthesis, we derive two approximate Bayes criteria for selecting a model from a collection of Markov random fields. The first criterion is based on a penalized maximum likelihood. The second criterion, a Markov chain Monte Carlo approximation to the first, has distinct computational advantages. Some simulation results are also presented.
Amyl xanthate uptake by natural and sulfide-treated cerussite and galena

Abstract The interaction of cerussite and galena with hydrosulfide and aqueous amyl xanthate at pH 9.5 has been investigated through zeta potential measurements. Zeta potential results indicate that the hydrosulfide and xanthate anions chemisorb or participate in surface reactions at both the cerussite and galena/solution interfaces. Molecular lead xanthate appears to cover the surface of amyl xanthate-treated cerussite whereas chemisorbed xanthate covers the surface of galena under the same conditions. Sulfidization of the mineral surface, which sets in only after sufficient sulfide is added to precipitate aqueous lead as lead sulfide, causes the zeta potential to drop sharply to highly negative values. The redox potential sensed by a Pt electrode remains almost constant at low reagent dosages, and becomes more negative once the hydrosulfide and amyl xanthate report to the solution. Excess sulfide in solution, an indication of oversulfidized mineral surfaces, lowers the redox potential and inhibits amyl xanthate adsorption. Redox potential measurements may aid in achieving an efficient sulfidization of cerussite and oxidized galena for optimum xanthate adsorption and therefore flotation.
Electro-optical characterization and modeling of thin film CdS-CdTe heterojunction solar cells

Abstract Optoelectronic characteristics of thin film CdTe–CdS solar cells fabricated at four different laboratories were measured and analyzed. Current versus voltage measurements revealed that, under one sun illumination, tunneling was the dominant current flow mechanism in all cells. Tunneling was also the dominant current flow mechanism in the dark for all types except P3 which exhibited a generation-recombination type current flow process in the dark. A theoretical model involving bulk traps in CdTe and a charged thin layer (T-layer) near the junction under forward bias and/or illumination was developed. The model is able to explain all significant features in the experimental results obtained from current versus voltage, and capacitance.
The relationship between children's perceived and actual motor competence

To examine the relationship between children's perceived and actual motor competence, 218 children between the ages of 9 and 11 years individually completed the Motor Skill Perceived Competence Scale. After completing the scale, the subject's actual motor competence was measured on a series of gross motor tests. Incomplete principal component analysis identified two actual motor competence dimensions from the motor test battery. The two factors included a lower-body and an upper-body factor of actual motor competence. A two-factor analysis of variance indicated that the boys and girls differed in perceived competence and actual competence. The boys showed higher perceived competence and actual motor competence. In addition, the 9-, 10-, and 11-year-old age groups differed from each other on the lower-body factor of actual motor competence. As age increased, lower-body competence increased. Regression analysis indicated that actual and perceived motor competence was moderately correlated. Adding age to the multiple regression model significantly increased the multiple correlation. Adding gender to the model did not increase the correlation, showing that perceived competence was a function of actual motor competence and age, and this finding held for boys and girls. These findings showed that 9-, 10-, and 11-yr-old children can assess personal motor competence. However, practitioners should attempt to understand children's perceived competence given that their assessments are not extremely accurate.
Direct construction of a chromosome-specific NotI linking library from flow-sorted chromosomes

A linking library consists of genomic DNA fragments which contain a specific rare restriction enzyme site; such clones are very useful as probes in pulsed field gel electrophoresis and in mapping and cloning large regions of DNA. However, identifying those linking clones which map to a certain chromosomal region can be laborious. Therefore, we have developed a straightforward procedure for constructing a linking library directly from flow-sorted chromosomes. As a test of the approach, a NotI linking library was constructed from the chromosome 17 fraction of a flow-sort of human chromosomes, using only 70 ng of DNA. Thirteen of sixteen linking clones were mapped to chromosome 17, suggesting that the library is highly enriched for this chromosome. This method should be generally applicable to other chromosomes and enzymes as well.
Choice in the Lottery-Insurance Situation Augmented-Income Approach

I. Introduction, 148. — II. The model, 150. — III. The nature of market imperfections, 152. — IV. Summary and implications, 153.
Position-taking in House debate and the issue of immigration

Traditional studies of legislative behavior often rely on analyses of roll-call votes. However, this approach ignores variation in legislator position that may not be expressed through a recorded vote. To better examine legislative position-taking, I rely on legislative speech and explore what factors motivate a member of Congress to take a position on immigration. I apply Wordfish, a text-scaling algorithm, to House debate from the 104th and 109th sessions of Congress in order to estimate each legislator's position on immigration. This approach facilitates a more nuanced understanding of legislative position-taking enabling us to speak to the degree of support or opposition to a particular policy – something we are unable to extract from studies relying on vote data alone. Results indicate first, the factors influencing legislative speech have changed over time, with institutional motivations playing a greater role than constituent preferences in determining positions; and second, the issue has become in...
Etiology and outcome of lower gastrointestinal bleeding in patients with AIDS

Objective: The objective of the study was to investigate bleeding (LGIB) in patients with acquired immunodeficiency syndrome (AIDS). Methods: All hospitalized AIDS patients with LGIB evaluated by the gastroenterology service at a large city-county hospital during a 6 yr period were identified by database review and by endoscopy and consultation records. Results: Of the 691 AIDS patients seen during the study period, 18 (2.6%) (median age 41 ± 7 years) were evaluated for LGIB. In these patients, LGIB was caused by human immunodeficiency virus type 1 (HIV)-associated disorders in 72% including cytomegalovirus colitis in seven patients, idiopathic colonic ulcers in five patients, and intestinal Kaposi's sarcoma in one patient. HIV-associated thrombocytopenia contributed to substantial bleeding from hemorrhoidal disease in two patients. Rebleeding occurred in four patients (22%), including hemorrhoids in three and idiopathic colonic ulcers in one. Surgery was not performed in any patient. Following the institution of ganciclovir therapy, no patient with CMV colitis had recurrent bleeding. The in-hospital mortality was high (28%), although bleeding was the direct cause of death in only one patient. Conclusions: LGIB is infrequent in patients with AIDS and is usually caused by opportunistic diseases specifically related to immunodeficiency. Although some of these conditions are potentially treatable medically, in-hospital mortality is high and long-term prognosis is poor because of AIDS-related comorbidity.
Glacial stratigraphy of Stough Creek Basin, Wind River Range, Wyoming

Abstract Multiparameter relative-age (RA) techniques identify four post-Pinedale morphostratigraphic units in each of three cirque valleys tributary to Stough Creek Basin, Wind River Range, WY. Soil development, lichenometry, boulder weathering characteristics, and the geomorphic relations among morphostratigraphic units indicate glacial deposits here correspond to the sequence previously described in the Temple Lake valley [Arct. Alp. Res. 6 (1974) 301]. Cirque deposits in Stough Creek Basin correspond to the Temple Lake, Alice Lake, Black Joe, and Gannett Peak alloformations [GSA Abs. Prog. 32 (2000) A-16]. 10 Be ages from moraine boulders and polished-striated bedrock [Assoc. Am. Geogr. Annu. Mtg. Abs. (2000) 155] support recent numeric age estimates from Temple Lake and Titcomb Basin that indicate the Temple Lake Alloformation corresponds to the Younger Dryas climate episode [Geogr. Phys. Quat. 41 (1987) 397; Geology 23 (1995) 877; Science 268 (1995) 1329; GSA Abs. Prog. 31 (1999) A-56]. Soils described from Pinedale recessional deposits here represent the first systematic description of Pinedale alpine deposits in the WRR.
Biodistribution and metabolism of targeted and nontargeted protein-chelate-gadolinium complexes: Evidence for gadolinium dissociation in vitro and in vivo

The intracellular metabolism of receptor-targeted 153Gd-DTPA-glycoproteins was studied in vitro and in vivo. These agents bound to cell surface receptors, underwent receptor mediated endocytosis, and were rapidly degraded to a metabolite which co-migrated with a 153Gd-DTPA-lysine standard on thin layer chromatography. The rates of dissociation of 153Gd and 111In from a glycoprotein-chelate conjugate were determined in vitro. Gadolinium readily dissociated, in a pH-sensitive manner, from glycoprotein-DTPA, and to a lesser degree glycoprotein-MX-DTPA. The biodistribution of targeted and blood pool 153Gd111In labeled proteins also suggested that gadolinium dissociates from protein-DTPA and protein-MX-DTPA and their metabolites leading to an accumulation of gadolinium in bone. Metal-DTPA-glycoprotein agents targeted to cell surface receptors can still produce very high concentrations of radioactive or paramagnetic metals within the lysosome due to the high rate of accumulation afforded by receptor mediated endocytosis and the low release rate of metabolites such as metal-DTPA-lysine. However, the continued development of gadolinium based macromolecular agents will require improvements in bifunctional chelates.
Room Temperature CW Operation of Mid-IR Distributed Feedback Quantum Cascade Lasers for $\hbox{CO}_{2}, \hbox{N}_{2}$ O, and NO Gas Sensing

We present the design and the performance of midinfrared distributed feedback (DFB) quantum cascade lasers (QCLs) made of strain balanced GaxIn1-xAs/AlyIn1-yAs material on InP substrates for sensing CO2, N2O, and NO in the middle wavelength range of mid-IR from 4 to 6 μm. We present the performances of our DFB QCLs at three different aspects: high power, low threshold power consumption, and wide wavelength coverage. We demonstrated a continuous wave (CW) DFB QCL with an output power of 220mW at 20°C, a CW DFB QCL with low threshold voltage of 8V and low-divergent far-field angles of 27.5° × 32.9° by reducing the number of quantum cascaded stages, a CW DFB QCL with a low threshold power consumption of 0.7W by reducing doping density in the active core, and DFB QCLs wide wavelength coverage of 325 cm-1, 16.9% of center wavelength at 5.2 μm, within one wafer by changing the grating period. 12 DFB QCL chips have being aged for 3000 h under 25°C and a constant quasi-CW current of 0.37 A. No decrease in power was observed.
Surface Studies of Laser Annealed Semiconductors

The surface regions of semiconductor single crystals have been examined following laser annealing in an ultrahigh vacuum environment with the output of a pulsed ruby laser. Atomically clean surfaces with impurity levels below 0.1% of a monolayer can be produced by multiple pulse irradiation. Ordered surface structures are produced on low index oriented crystals as well as crystals slightly misoriented. Metastable surface structures exhibiting (1x1) LEED patterns have been produced on (111) orientations and are believed to be a consequence of the rapid coolig rates of 10/sup 9/ degs/sec achieved with the laser irradiation process. The surface and subsurface regions of ion-implanted Si crystals have been examined both before and after laser irradiation and results obtained from Si samples implanted with As are discussed.
Ultrathin film deposition by liquid CO2 free meniscus coating-uniformity and morphology.

Ultrathin organic films of sucrose octaacetate (SOA) were deposited on 12.5 cm diameter silicon wafer substrates using high-pressure free meniscus coating (hFMC) with liquid CO2 (l-CO2) as a coating solvent. The dry film thickness across the wafer and the morphology of deposited films were characterized as a function of coating conditionswithdrawal velocity, solution concentration, and evaporation driving force (ΔP). When no evaporation driving force was applied (ΔP = 0), highly uniform films were deposited with thickness in the range of 8−105 A over the entire concentration range (3−11 wt%). Uniform films were also obtained at low concentrations (3−5 wt%) with a low evaporation driving force (ΔP = 0.0138 MPa). However, films deposited at medium to high concentrations (7−11 wt%) were thicker (110−570 A) and less uniform, with larger nonuniformities at higher applied evaporation driving forces. Optical microscopy and atomic force microscopy (AFM) were used to characterize film morphology including drying d...
Laticiferous plants of economic importance III. Couma species

The commercial use of the exudation of several species of Couma as a source of gutta-gum is of recent development. Although the edible fruits have been known in the Amazon basin since prehistoric time, and the coagulated latex, or coagulum, is favored by the South American Indian for caulking dugouts and canoes, the utilization of this gutta-gum in industry, especially in the United States, began only about 30 years ago.
Use of clinical assessment tools in the evaluation of fracture healing

Fracture healing is an optimized biological process yet the ability to determine when a fracture is healed, or to measure the healing response can present a clinical challenge. This review will focus on the evidence for the implementation of imaging modalities as tools to assist in evaluating fracture union. This is particularly important for common fractures that have a propensity to have delayed union or non-union, where a diagnosis of non-union would alter the treatment. We also present methods, such as biochemical markers and clinical scores that are in development or have the potential to aid in the diagnosis of non-union. Ultimately, clinical exam combined with the available modalities can help the clinician judge the progression of healing with some confidence. There is still a need for continued development of new modalities and tests to improve accuracy of the diagnosis of non-union, as well as predict which fractures are at risk for non-union.
Personal influences that affect motivation in pap smear testing among African American women.

ABSTRACT Objective To explore personal influencing factors that contribute to Papanicolaou (Pap smear) testing in African American women who do (routine-use group) and do not (non-routine-use group) obtain routine testing. Design Qualitative using the interaction model of client health behavior. Setting Community programs, homes, and churches. Participants Twenty four African American women aged 19 to 60. Methods Face-to-face interviews. Data were analyzed using a constant comparison approach. Results Routine-use group was socially influenced to value preventive health care while the non-routine-use group was not. Previous health care experiences with having a Pap smear and pelvic exam were positive for routine-use group and negative for non-routine-use group. Cognitively, both groups believed Pap smears tested for cancer and sexually transmitted diseases. Vulnerability to cervical cancer was thought to run in families; participants believed they were either safe from risk or hoped that the odds were in their favor. In addition, there was a link between avoiding routine preventive care and a trauma history (sexual, physical, medical), eliciting negative perceptions towards Pap smears and pelvic exams. Conclusion Differences and similarities in personal influencing factors associated with cervical cancer screening were found in the two groups. Further research is needed to explore these differences and similarities because they may contribute to the reason that African American women have a greater mortality rate from cervical cancer than White women.
An Upper Bound on the Critical Temperature for a Continuous System with Short-Range Interaction

A classical gas with short-range interaction in the grand canonical ensemble is studied. Ifp(β, z) denotes the thermodynamic pressure at inverse temperatureβ and activityz, then it follows from the Mayer expansion thatp(β, z) is infinitely differentiable providedβ andβz are sufficiently small. Here it is shown that there existsβ 0>0 such thatp(β, z) is infinitely differentiable ifβ<β 0 andz>0. One can interpret this result as saying that (β 0)−1 is an upper bound on the critical temperature for the system.
Coastal wave generation in the Bohai Bay and propagation along the Chinese coast

The Bohai Bay and Yellow Sea experience sea surface height (SSH) changes of 20 cm and larger during wintertime northerly and southerly wind bursts that have a time scale of a few days. These large SSH changes give rise to coastal shelf waves that subsequently propagate southward along the Chinese coast. Two models provide observations of these waves. The first one is a statistical model based on four years of TOPEX/POSEIDON (T/P) altimeter SSH observations and Navy Operational Global Atmospheric Prediction System (NOGAPS) wind stress fields. The second model is a numerical model forced by the wind stress. The numerical model provides an objective interpretation of the wind stress response based on dynamical equations. The statistical model is based on observations with a linear response to the wind forcing and thus complements the numerical model. The observed waves closely resemble gravest mode shelf waves derived by analytical solutions.