cssi/SciSciGPT-SciSciNet huggingface dataset:
Magma storage and diking revealed by GPS and InSAR geodesy at Pacaya volcano, Guatemala

GPS measurements from a campaign network at Pacaya volcano, Guatemala, occupied from 2009 to 2015 were combined with InSAR data from 2013 to 2014 to model deformation sources for two eruptive time periods: 2009–2011 and 2013–2014. The GPS data for both of these time periods show downward vertical and outward horizontal deformation greater than 25 cm at several stations surrounding the volcano, while InSAR data shows up to 15-cm line-of-sight displacement. To better understand the dynamics of the magma storage system and sources of deformation, we inverted available geodetic data for these two periods. Our analytical modeling suggests that horizontal deformation was dominated by inflation of a shallow, subvertical dike, high within the volcanic edifice, while deflation of a deeper, spherical source embedded below the NW flank of the volcano occurred during at least part of the observation period. The source parameters for the dike feature are in good agreement with the observed alignment of recent eruptive vents, while parameters for the deeper, spherical source accommodate the downward vertical deformation observed at stations on and around the volcano.
Urban Data and the Platform City

How will urban data, and the platforms through which we access and commodify urban data, affect the way we live in and govern twenty-first century cities? This short chapter offers a concise outline of how urban data is fundamentally altering the the structure of urban governance. The chapter also explores how both local governments and non-governmental actors should approach the new frontier that data-based governance offers.
Extracellular ATP-induced apoptosis in PC12 cells.

Studies in our laboratory indicate that extracellular ATP (ATP)0 may induce cell death by reactive oxygen insults. We have also shown that the Ca2+-induced oxidative stress as elicited by ATP may lead to an activation of a specific AP-1 activity. Since early impairment of mitochondria constitutes a critical event of the apoptotic cell death, we have examined whether (ATP)o will affect mitochondrial damage and cell injury by using mitochondrial specific probes, dihydrorhodamine and 3-(4,5-dimethylthiazo-2-yl)-2,5-diphenyl tetrazolium bromide (MTT). We have found that (ATP)o induced cell death in a concentration dependent manner by MTT assay. The (ATP)o induced cell death correlated well with the reactive oxygen species (ROS) generation in mitochondria, since (ATP)o enhanced both cell death and ROS production and antioxidant blocked both of these processes. We found (ATP)O treatment led to apoptotic cell death by examining DNA laddering and the TUNEL assay. Interestingly, vitamin C and vitamin E combined treatment appeared to attenuate the (ATP)o-induced apoptosis. Results indicated that (ATP)o may cause oxidative damage of mitochondria leading to apoptotic cell death. Antioxidants may be useful in preventing apoptosis by preventing ROS formation in mitochondria.
UNIT 17.3 MHC-Peptide Tetramers to Visualize Antigen-Specific T Cells

Mature T lymphocytes of the CD8 or CD4 classes bear αβ T cell receptors (TCR) that are specific for a molecular complex consisting of a major histocompatibility complex class I or II (MHC class I or II) molecule bound to a unique self or foreign peptide. Until recently, methods for monitoring antigen-specific T cell immune responses were restricted primarily to functional assays based on limiting dilution analysis, because the lack of specific molecular reagents to identify clonal T cells obviated approaches to identify and enumerate specific T cells. Development of efficient methods to express and refold MHC class I molecules with synthetic peptides coincided with identification of specific protein sequences that provide the substrate for enzymatic biotinylation. This combination has led to the development of a straightforward method for generating synthetic TCR ligands, making them tetravalent to provide increased avidity, and labeling them through a streptavidin moiety with useful fluorescent tags such as allophycocyanin or R-phycoerythrin. This unit describes the preparation of MHC class I/peptide tetramers in detail, including bacterial expression and refolding of the MHC class I light chain, β2-microglobulin (β2m), as well as the formation of a complex consisting of the MHC class I heavy chain of interest, β2m, and a chosen peptide. © 2016 by John Wiley & Sons, Inc. Keywords: MHC tetramers; T cells; flow cytometry
The Mushroom Project Model: A Note

The concept and scope of a project appear to be different depending upon the area of industry or commerce. The following model can be used to explain the differences of approach to project management by different groups and puts into context the key expectations of a business project. The objective is to recognise that the concept of a project varies depending upon familiarity with a particular industry sector and that all are usually correct for that environment. In this narrative several views are expressed by the author that are deliberately polarised to exaggerate differences in the view; in reality there are many shades of grey.
Glendale's Ethnopolitical Entrepreneurs: Suburban Immigrant Political Incorporation

Concentrated immigrant settlement of US suburbs is transforming how many newcomers become politically incorporated. While the scholarship traditionally assumed political incorporation takes place a...
A Tutorial on Theoretical and Computational Techniques for Gas Breakdown in Microscale Gaps

Paschen’s law (PL), derived based on the Townsend avalanche (TA) condition, is commonly used to predict gas breakdown. For microscale gaps near atmospheric pressure, TA is insufficient to drive breakdown and ion-enhanced field emission (FE) dominates. Accurately predicting breakdown voltages for these gaps is critical for numerous applications, including environmental remediation, medicine, combustion, and propulsion. This tutorial summarizes theoretical and computational approaches for predicting this behavior and demonstrating the transition between the TA and FE mechanisms. It focuses on the derivation of closed-form solutions from a theory that accounts for the generation of additional positive space charge at the cathode due to electrons generated by the strong FE-induced electric fields. Appropriate simplifications using a matched asymptotic analysis in terms of the total ionization in the gap agree well with simulations and experiments and show the transition from FE for small gaps to PL at larger gaps. Specifically, this theory shows that the breakdown voltage varies linearly with gap distance when FE dominates, agreeing with both the experimental and simulation results. The particle-in-cell Monte Carlo collision (PIC/MCC) simulations used to predict the ionization coefficient provide additional insight into the mechanisms involved. Future benefits of extended theoretical and computational research for examining microscale and nanoscale breakdown and electron emission, particularly assessing the impact of electrode surface structure and device design and coupling with additional emission mechanisms, will be discussed.
The Diné (Navajo) Hózhó Lifeway: A Focused Ethnography on Intergenerational Understanding of American Indian Cultural Wisdom.

Purpose: Hozho is the cultural wisdom that guides the Dine lifeway. This study examines understanding of cultural wisdom (CW) across three generations: elders, adults, and adolescents. Method: A focused ethnography was conducted on the Navajo Nation. Twenty-two Dine (Navajo) were recruited through convenience sampling. Data were collected via two semistructured interviews and photovoice methods. Data were analyzed using content analysis, thematic analysis, and participatory visual analysis of photos. Results: The Dine elders embodied the greatest in-depth understanding of CW followed by the adolescents. An unexpected finding was the scarcity of understanding of CW among the adults. Conclusion: The Dine understanding of CW is transferred through discussion with elders, listening to and speaking traditional language, cultural preservation activities, and participation in cultural practices. The Dine believe cultural wisdom is a health sustaining protective factor, therefore strategies to restore, promote, and support the intergenerational transfer of cultural wisdom remains a tribal priority.
Does Lowering Hemoglobin A1c Reduce Penile Prosthesis Infection: A Systematic Review.

Abstract Introduction Hemoglobin A1c (HbA1c), a glycated form of hemoglobin, develops when glucose is elevated in the blood. It is used as a marker of how well a diabetic patient has been controlling their blood sugar over the previous 3–4 months. Some use HbA1c as a predictor of infection risk during prosthetic surgery, and many surgeons require patients to lower it preoperatively. Objective This study was designed to comprehensively review the literature relating HbA1c and penile prosthesis (PP). Methods A PubMed search of English-language articles identified studies that investigate the relationship between HbA1c levels and PP infection. Studies were only included if they reported the mean HbA1c of all PP patients and compared patients who did/did not develop a prosthetic infection. References from relevant articles are included. Results A total of 6 studies, 1992–2020, were identified. 2 studies occurred before the advent of antibiotic-enhanced devices in the early 2000s and have limited applicability to the modern era. Of the 4 studies published after, 2 reported a significant difference in mean HbA1c when comparing patients who developed a prosthetic infection and those who did not (9.1% vs 7.5%, P = .000 and 9.5% vs 7.8%, P .05; and 7.6% vs 7.5%, P = .598). Conclusion Current data regarding HbA1c as a predictor of PP infection are inconclusive, with no consensus. HbA1c is increasingly used as a predictor of postsurgical prosthetic infection, with some urologists requiring patients with elevated HbA1c to acutely lower it before elective surgery. While there are a number of established health benefits of controlling elevated blood sugar, larger randomized controlled trials need to validate whether acutely lowering perioperative HbA1c decreases risk of prosthetic infection. Dick BP, Yousif A, Raheem O, et al. Does Lowering Hemoglobin A1c Reduce Penile Prosthesis Infection: A Systematic Review. Sex Med Rev 2021;9:628–635.
Predictors of appointment adherence following operative treatment of pediatric supracondylar humerus fractures: which patients are not following up?

This study aims to identify characteristics associated with poor appointment adherence after surgical stabilization of supracondylar humerus fractures (SCHFX) in children. A retrospective review of 560 consecutive, surgically managed patients with SCHFX from 2010 to 2015 was performed. One missed follow-up appointment was classified as 'low adherence', whereas missing two or more appointments was classified as 'very low adherence'. Demographics, insurance status, estimated family income and distance from clinic were analyzed to identify differences in variables between adherent and low-adherent groups. Of 560, 121 (21.8%) missed one follow-up visit and 39/560 (7.1%) missed more than two visits. Age, gender, distance traveled, insurance status and primary language were nonpredictive. Estimated income 200% increase in low adherence vs patients with estimated income >$50 000 (9.3 vs 3.8%; P = 0.012). African American patients had significantly lower adherence vs patients of other races (47.5 vs 19.6%; P < 0.0001). Ethnicity remained the only significant factor correlated to adherence after multivariate analysis. African Americans were three times more likely demonstrate low adherence (P = 0.0014). Ethnicity and estimated income <$50 000 were predictors of missing two or more visits. African American patients were four times more likely to miss two or more visits [odds ratio (OR), 4.17; P = 0.0026] than others; estimated income <$50 000 was associated with a two-fold increase in missing two or more visits (OR, 2.33; P = 0.035). By identifying at-risk patient populations, healthcare systems can adopt strategies to remove barriers of accessing follow-up care.
Optimizing thermal block length during infrared neural inhibition to minimize temperature thresholds.

Objective. Infrared neural inhibition (INI) is a method of blocking the generation or propagation of neural action potentials through laser heating with wavelengths strongly absorbed by water. Recent work has identified that the distance heated along axons, the block length (BL), modulates the temperature needed for inhibition; however, this relationship has not been characterized. This study explores how BL during INI can be optimized towards minimizing its temperature threshold.Approach. To understand the relationship between BL and the temperature required for INI, excised nerves fromAplysia californicawere laser-heated over different lengths of axon during electrical stimulation of compound action potentials. INI was provided by irradiation (λ= 1470 nm) from a custom probe (n= 6 nerves), and subsequent validation was performed by providing heat block using perfused hot media over nerves (n= 5 nerves).Main Results. Two BL regimes were identified. Short BLs (thermal full width at half maximum (tFWHM) = 0.81-1.13 mm) demonstrated that increasing the tFWHM resulted in lower temperature thresholds for INI (p 0.0125). Validation of this longer regime was performed using perfused hot media over different lengths of nerves. This secondary heating method similarly showed no significant change (p> 0.025) in the temperature threshold (tFWHM = 1.25-4.42 mm).Significance. This work characterized how the temperature threshold for neural heat block varies with BL and identified an optimal BL around tFWHM = 1.13 mm which minimizes both the maximum temperature applied to tissue and the volume of tissue heated during INI. Understanding how to optimally target lengths of nerve to minimize temperature during INI can help inform the design of devices for longitudinal animal studies and human implementation.
Cellular Receptors of Picornaviruses: an Overview

The most surprising result of studies focused on early events in animal virus infection is the diversity of cell surface proteins serving as receptors. Two viruses belonging to two entirely different families, say, the small RNA coxsackievirus B and the large DNA adenovirus 2, have chosen the same small cell surface protein as receptor (CAR). Perhaps Retroviridae assembled the most diverse menu of cellular receptors. Most receptors belong to the immunoglobulin (Ig) superfamily or the integrin receptor family. Considering the many unresolved puzzles concerning enterovirus entry, and the steady expansion of picornavirus genera, the number of picornavirus receptors can increase significantly in the future. The cellular function of integrins includes binding extracellular matrix proteins, cell-cell interactions, and signal transduction. Decay accelerating factor (DAF) (CD55) is a member of the regulator of the complement activity protein family and protects the cell from autologous lysis. Heparan sulfate has been implicated in receptor function for certain strains of foot-and-mouth disease virus (FMDV) and clinical isolates of echovirus 6. The difference in receptor utilization not only yields host range phenotypes in vitro, but it has also a profound effect on pathogenesis in animals. The polypeptide chain of decay-accelerating factor (DAF) consists of four short consensus sequences (SCRs), some of which are involved in virus binding. Pathogenesis is determined by tissue tropism, spread of the virus to target tissues, and virulence.
Howell-Jolly bodies on peripheral smear leading to the diagnosis of congenital hyposplenism in a patient with septic shock

We present a case of isolated congenital hyposplenism that was discovered after the peripheral smear revealed Howell-Jolly bodies. This case serves as the basis for a review of hyposplenism for the general practitioner.
Compulsory Schooling Laws and In-School Crime: Are Delinquents Incapacitated?

Minimum dropout age (MDA) laws have been touted as effective policies to bring dropouts off streets and into classrooms. One question to better understand the costs and benefits of these laws is: to what extent do MDA laws displace crime from streets to schools? This research expands the compulsory schooling literature and extends the sparse research on in-school crime by studying how MDA laws affect crimes committed in U.S. public high schools. The analysis is conducted using a difference-in-difference estimator exploiting variation in state-level MDA laws over time. The results indicate that an increase in the MDA to 18 significantly increases in-school crime by 0.434 incidences per 1,000 students or a 6.2% increase. Analyzing specific crime types, the results find that attacks without a weapon, threats without a weapon, and illegal drug incidences increase by 0.627, 0.588 and 0.437 incidences (or 12.2%, 36.3%, and 43.4% increase), respectively. An increase in the MDA to 17 is found to have no effect on in-school crime. The results are robust across different socioeconomic student bodies and control groups. Lastly, we find that in-school crime prevention resources do not increase with an increase in the MDA, but that utilization rates of suspensions and expulsions change in the direction of fortifying state policymakers efforts to keep juveniles in schools.
Interface cracks in layered materials subjected to a uniform temperature change

Elastic and incremental elasto-plastic analyses have been used to evaluate the driving force for interface edge-crack growth initiation in tri-layered material systems subjected to a monotonic variation in temperature. Whenever possible, closed-form solutions are derived as functions of the thermo-mechanical material properties and the geometry of the layers. Analytical expressions for the different critical temperatures at which distinct transitions occur in thermally induced deformation are presented and are correlated with the three regimes of interface fracture; elastic, partially plastic and fully plastic. Furthermore, a large-scale contact model, which predicts the shielding effect of contact in the wake of an interface crack, is also presented and the attendant reduction in the energy release rate is estimated. Finite element results, showing the influence of layer geometry and strain hardening on the energy release rate, are presented for a model Al2O3/Ni(Cr)/Al2O3 tri-layered system; these simulations confirm the bounds predicted by the theory.
Gender and Diversity in Organizations: Past, Present, and Future Directions.

This introduction reviews some of the key issues that have been studied by researchers focused on gender and diversity in organizations. Issues such as discrimination, affirmative action, barriers to career advancement, and sexual harassment at work are discussed. Although the study of gender and diversity in organizations has expanded in the last decade, key areas of research are still underrepresented. Issues for future research in this area are discussed.
Quantitative estimation of illite-smectite mixed phases formed during burial diagenesis

With reference to the previously published papers byReynolds andHower (1970) andPerry andHower (1970) pelitic sediments from bore hole samples from the Tertiary sequence of the Vienna Basin have been studied to investigate the layer silicate assemblages and to carry out a quantitative estimation of the mixed-layering in the illitesmectite mixtures. Beside these problems one of the primary purposes of this paper is to indicate how interfering reflections from detrital layer silicates can be handled and resolved from diffraction patterns. The samples correspond to clayey silts. Within the less than 0.2 micron fractions they essentially contain mica, kaolinite and illite-smectite as expandable phase. Dependent on depth the composition of these mixtures is intermediate between an interstratified mixed layer phase consisting of about 75 percent smectite layers and 25 percent illite and an ordered mixture which contains about 20 percent smectite and 80 percent illite layers.
Satellite-based personal communications networks

One of the main requirements from personal communication networks is to provide the user with ubiquitous services. i.e., coverage every place, every time on a global basis. Terrestrial-based systems make economical sense only for coverage of the populated areas. However, this implies coverage over a small percentage of the face of the globe. In order to provide coverage of the non-populated areas satellite-based systems provide the solution. These systems are under construction and are planned to enter the phase of providing commercial services in the near future. The deviation of these systems compared to the common cases are reviewed. A particular emphasis is given to European aspects. Several satellite based systems are under construction for operating in the frequency bands between 1610 to 1626.5 MHz and 2483.5 to 2500 MHz. A future emerging band for mobile satellite systems (MSS) is the band 1980 to 2010 MHz paired with 2170 to 2200 MHz in the framework of the FPLMTS.
Lonidamine as a modulator of alkylating agent activity in vitro and in vivo.

We are searching for relatively nontoxic compounds that can positively modulate the efficacy of antitumor alkylating agents. Lonidamine inhibits cellular energy metabolism and could potentially increase damage by alkylating agents if cellular defenses are energy requiring. Exposure of cells to lonidamine (500 microM) for 2 h under hypoxic conditions followed by 1-h exposures to lonidamine plus alkylating agents under normally oxygenated conditions in vitro significantly increased the cell kill achieved by cis-diamminedichloroplatinum(II) (CDDP) approximately 5-fold and by D-tetraplatin approximately 10-fold at 90% inhibitory concentration in MCF-7/CDDP (CDDP-resistant) cells. Carboplatin cytotoxicity, however, was little changed. In the MCF-7 parent cell line, treatment with lonidamine increased CDDP cytotoxicity by approximately 10-fold, D-tetraplatin by approximately 10-fold, and carboplatin by approximately 8-fold at the 90% inhibitory concentration. For L-phenylalanine mustard (melphalan), N,N',N"-triethylenethiophosphoramide (thiotepa), and N,N'-bis(2-chloroethyl)-N-nitrosourea, little resistance was evident in the MCF-7/CDDP lines compared with the parent line. Treatment with lonidamine increased the cytotoxicity of each drug by 1.5- to 3-fold in both cell lines. When exposure to lonidamine was extended to 24 h before and 12 h after drug exposure in MCF-7 normally oxygenated cultures, CDDP (250 microM) cytotoxicity was increased by approximately 100-fold, but melphalan cytotoxicity was increased only 2- to 3-fold over the concentration range tested. In the FSaIIC murine fibrosarcoma tumor system, five i.p. injections of 50 mg/kg of lonidamine over 36 h increased the tumor cell kill by CDDP and carboplatin approximately 2- to 3-fold over the dose range tested when the platinum complexes were given i.p. immediately after the third lonidamine injection. When cyclophosphamide and thiotepa were given in the same schedule, 10-fold increases in tumor cell killing were evident on tumor excision assay over the dosage ranges. The increase in bone marrow toxicity caused by lonidamine in addition to the alkylating agents was less than for tumor cells. Finally, in the EMT6 murine mammary carcinoma, use of lonidamine at 500 mg/kg twice daily along with CDDP, carboplatin, thiotepa, and cyclophosphamide significantly increased tumor growth delays by approximately 1.6- to 3.0-fold. The results suggest that lonidamine can positively modulate antitumor alkylating agent cytotoxicity and may be a clinically useful adjunctive therapy with these drugs.
Retrospective evaluation of hyperosmolar hyperglycemia in 66 dogs (1993–2008)

Objectives To clinically characterize a large group of dogs with the hyperosmolar hyperglycemic state (HHS) and to determine whether 2 HHS subgroups, dogs with hyperosmolar ketonuric (HK) diabetes mellitus (DM) and dogs with hyperosmolar nonketonuric (HNK) DM were clinically different from one another. Design Retrospective study. Records of 1,250 diabetic dogs that were examined between January 1993 and July 2008 were reviewed in order to identify dogs with HHS. Inclusion required a calculated serum osmolality ≥325 mOsm/kg, with or without ketonuria. Setting University teaching hospital. Animals Sixty-six dogs with HHS including 34 dogs with HK, 25 dogs with HNK, and 7 dogs with unclassified HHS. Interventions None. Measurements and Main Results HHS was diagnosed in 5% of dogs with DM. HK and HNK dogs were similar to one another in regard to most historical, physical examination, and clinicopathologic variables as well as outcome. Sixty-two percent of dogs with HHS survived to discharge from the hospital. Poor outcome of HHS dogs was associated with abnormal mental status (P = 0.03) and a low venous pH (P = 0.045). Dogs with HK were significantly more likely to have acute pancreatitis (P = 0.046), higher body temperature (P = 0.006), higher WBC count (P = 0.01), and a shorter duration of clinical signs (P = 0.02) compared to dogs with HNK. Dogs with HNK had significantly higher BUN and creatinine concentrations (P = 0.0002 and P = 0.008, respectively) and higher calculated osmolality (P = 0.001) compared to dogs with HK. Conclusions HHS is a rare condition in which poor outcome is associated with abnormal mental status and low venous pH. Among dogs with HHS, the subgroup of dogs with HK has significantly more acute pancreatitis, shorter duration of clinical signs, and higher body temperature and WBC count compared to dogs with HNK, whereas dogs with HNK have more azotemia and higher calculated osmolality compared to dogs with HK.
Use of Atomic Layer Deposition to Improve the Stability of Silver Substrates for In-Situ, High Temperature SERS Measurements

A method to stabilize silver surface-enhanced Raman spectroscopy (SERS) substrates for in-situ, high temperature applications is demonstrated. Silver island films grown by thermal evaporation were coated with a thin layer (from 2.5nm to 5nm) of alumina by atomic layer deposition (ALD), which protects and stabilizes the SERS-active substrate without eliminating the Raman enhancement. The temporal stability of the alumina-coated silver island films was examined by measurement of the Raman intensity of rhodamine 6G molecules deposited onto bare and alumina-coated silver substrates over the course of thirty-four days. The coated substrates showed almost no change in SERS enhancement while the uncoated substrates exhibited a significant decrease in Raman intensity. To demonstrate the feasibility of the alumina-coated silver substrate as a probe of adsorbates and reactions at elevated temperatures, an in-situ SERS measurement of calcium nitrate tetrahydrate on bare and alumina-coated silver was performed at temperatures ranging from 25 C to 400 C. ALD deposition of an ultrathin alumina layer significantly improved the thermal stability of the SERS substrate thus enabling in-situ detection of the dehydration of the calcium nitrate tetrahydrate at elevated temperature. Despite some loss of Raman signal, the coated substrate exhibited greater thermal stability compared to the uncoated substrate.more » These experiments show that ALD can be used to synthesize stable SERS substrates capable of measuring adsorbates and processes at high temperature.« less
Acquired aorta-pulmonary artery fistula: diagnosis by multiple imaging modalities.

Abstract Acquired communication between the aorta and the pulmonary artery is a rare phenomenon. We describe two patients with a thoracic aortic aneurysm in whom the diagnosis of a communication with the pulmonary artery was first made on transthoracic echocardiography and then more completely elucidated by means of multiple imaging modalities: transesophageal echocardiography, epiaortic ultrasound, computed tomography, and magnetic resonance imaging. Representative images from these complementary studies are presented. A successful repair of the fistula was subsequently accomplished in both patients. (J Am Soc Echocardiogr 2001;14:842-5.)
Investigations of aeroelastic response for a system with continuous structural nonlinearities

Measurements and predictions of aeroelastic response are examined for a wing section mounted to permit continuous nonlinear structural response. Nonlinear behavior is introduced using a unique model support system designed to permit prescribed nonlinear stiffness characteristics. The wing section is limited to pitch and plunge response. Tailored experiments establish nonlinear responses such as limit cycle oscillations, and these results are predicted with an analytical model.
The application of neutron scattering to the relation between chain dimensions and miscibility for polyolefins

A method is described that can predict the miscibility of the great majority of polyolefins based just on their chemical architecture. The miscibility of polyolefins is shown to be essentially controlled by their solubility parameters, d, which in turn depend on the chain dimensions of the chains through the packing length lp. A method to estimate lp from chain architecture is also shown, giving a very powerful mechanism to predict the mixing thermodynamics from chemical structure.
Block Copolymer Assemblies with Cross-Link Stabilization: From Single-Component Monolayers to Bilayer Blends with PEO−PLA†

Amphiphilic diblock copolymers containing poly(ethylene oxide) (PEO) and saturated polybutadiene (PBD) hydrophobic chains have been cross-linked in both monolayer and bilayer assemblies. For monolayers, the Langmuir isotherm proves consistent with prior measures of density and compressibility for bilayer vesicles, and the monolayers can be macroscopically transferred as Langmuir−Blodgett films. Since the films are inverted (PBD oriented away from the slide) at the air−water interface, they spontaneously reorganize when immersed in water into wormlike micelles. However, this transition is quenched when the film is stabilized by free radical polymerization. Atomic force microscopy shows a stabilized but pitted film, which allows height measurements that prove consistent with a monolayer. With bilayer vesicles, we investigate several additional aspects of cross-linking. Spatial control of membrane cross-linking on the micrometer-scale is demonstrated by dynamic inflation−deflation of a membrane fixed to the ...
Data-intensive document clustering on graphics processing unit (GPU) clusters

Document clustering is a central method to mine massive amounts of data. Due to the explosion of raw documents generated on the Internet and the necessity to analyze them efficiently in various intelligent information systems, clustering techniques have reached their limitations on single processors. Instead of single processors, general-purpose multi-core chips are increasingly deployed in response to diminishing returns in single-processor speedup due to the frequency wall, but multi-core benefits only provide linear speedups while the number of documents in the Internet is growing exponentially. Accelerating hardware devices represent a novel promise for improving the performance for data-intensive problems such as document clustering. They offer more radical designs with a higher level of parallelism but adaptation to novel programming environments. In this paper, we assess the benefits of exploiting the computational power of graphics processing units (GPUs) to study two fundamental problems in document mining, namely to calculate the term frequency-inverse document frequency (TF-IDF) and cluster a large set of documents. We transform traditional algorithms into accelerated parallel counterparts that can be efficiently executed on many-core GPU architectures. We assess our implementations on various platforms, ranging from stand-alone GPU desktops to Beowulf-like clusters equipped with contemporary GPU cards. We observe at least one order of magnitude speedups over CPU-only desktops and clusters. This demonstrates the potential of exploiting GPU clusters to efficiently solve massive document mining problems. Such speedups combined with the scalability potential and accelerator-based parallelization are unique in the domain of document-based data mining, to the best of our knowledge.
Anticorrugating effect of hybridization on the helium diffraction potential for metal surfaces

Hybridization between the helium $1s$ orbital and the unoccupied metal states is corrugated in the opposite sense to the charge density. This explains the anomalous smoothness observed in helium diffraction for metal surfaces. With a simple model which includes hybridization for Ni, Cu, Pd, and Ag(110) surfaces, we obtain corrugations, softness, and well depths which are in good agreement with experiment, and also agree with self-consistent calculations of charge density.
A Theoretical Model for Compaction of Granular Materials

A theoretical model is developed for the description of the compaction of granular materials exemplified by granulated ceramic powders. Its predictions compare satisfactorily to results of uniaxial compaction tests of ceramic granules of lead magnesium niobate-lead titanate (PMN-PT), rutile, and spray-dried alumina. The theory uses volume-based statistical mechanics and an activation analogy to treat, in parallel, the rearrangement of granules and their deformation. Variation of the model incorporates a distribution of barriers to deformation, which can be considered to include the effects of statistical pressure distributions within the compact. Other curve-fitting schemes available in the literature are shown to correspond to particular cases of the theory, and a justification of the equations used in those schemes is provided on physical grounds.
Identification of Pathotypes in the Daylily Rust Pathogen Puccinia hemerocallidis

Daylily rust, caused by Puccinia hemerocallidis, has been present in the United States since 2000. In 2003, inoculations with a single isolate of P. hemerocallidis identified daylily cultivars with high levels of resistance to the fungus. The present study was carried out to determine if pathotypes of P. hemerocallidis are present in the south eastern United States. Sixteen isolates of P. hemerocallidis were each inoculated onto leaf segments from 19 daylily cultivars and the resulting disease phenotype assessed. A significant effect of rust isolate on host reaction phenotype was observed for nine of the 19 daylily cultivars. Five of the nine cultivars displayed reaction phenotypes with different isolates of P. hemerocallidis that included at least one susceptible or moderately susceptible and also resistant phenotypes. These results indicate that different pathotypes of the fungus are present in the south east United States. Daylily hybridizers interested in screening for host resistance to P. hemerocallidis will need to include multiple isolates of the fungus to allow for this host specialization.
Bromomisonidazole: Synthesis and Characterization of a New Radiosensitizer

4-Bromomisonidazole has been synthesized by direct bromination of misonidazole and has been characterized chemically and in animals. The compound is highly stable in vitro and in vivo and, relative to misonidazole, has an increased partition coefficient of 2.9 in octanol-water. In EMT-6/UW tumor-bearing mice, misonidazole and 4-bromomisonidazole (1 mmole/kg) sensitize tumors equally well to /sup 137/Cs ..gamma.. rays; sensitizer enhancement ratios of 1.9 (D/sub 0/ (- sensitizer)/D/sub 0/ (+ sensitizer)) were obtained for both drugs. Toxicity studies (LD/sub 50///sub 2 days/) showed that 4-bromomisonidazole is more toxic (LD/sub 50/<6.5 mmole/kg) than misonidazole (LD/sub 50/=9.05 mmole/kg=1.82 mg/g) in C3H/HeJ mice. Biodistribution studies of 4-(/sup 82/Br)bromomisonidazole in mice reveal that iv and ip routes of administration are equally effective in delivering the drug to tissue. The tumor:blood ratio reaches a maximum at 40 min postinjection. Tumor:blood ratios are similar to those for misonidazole; tumor:brain ratios are generally higher. Biodistributions of 4-(/sup 82/Br)bromomisonidazole and (/sup 82/Br)bromide ion are significantly different, suggesting that the label remains on the imidazole ring. Bromomisonidazole is stable, appears to retain its label in vivo, and has biodistribution and toxicity characteristics consistent with its high partition coefficient. It is at least as good a sensitizer as misonidazole. It maymore » retain other properties of misonidazole, which may make it directly cytotoxic to hypoxic cells or capable of binding in such cells. These properties suggest that it may be useful for imaging hypoxic cells in tumors as well as other tissues.« less
Characteristics of MSM detectors for meander channel CCD imagers on GaAs

Metal-Semiconductor-Metal (MSM) photodetectors on semi-insulating gallium arsenide (SIGaAs) have found widespread application as front-end detectors in receivers for optical fiber communications. Their major attributes are (a) simplicity of design and construction, (b) high responsivity, and (c) high speed of response. In this paper the performance of MSM detectors at short wavelengths is examined and considerations are given for their use in GaAs charge-coupled-device (CCD) imagers. The simplicity of their structure allows MSM detectors to be easily integrated with two-phase meander channel CCD registers in GaAs for production of high speed light scanners. Test results show that GaAs MSM detectors have high sensitivity in the wavelength range from 200 to 800 nm and good linearity over three orders of magnitude variation of the incident intensity. These features make MSM detectors potential candidates for both linear and 2-D light scanners for ultraviolet (UV) spectrophotometry and astronomy.
Software system for computing material and structural properties of bone and muscle in the lower extremity from pQCT

Peripheral Quantitative Computed Tomography (pQCT) is a non-invasive imaging technology that is well-suited for quantification of bone structural and material properties. Because of its increasing use and applicability, the development of automated quantification methods for pQCT images is an appealing field of research. In this paper we introduce a software system for hard and soft tissue quantification in the lower leg using pQCT imaging data. The main stages of our approach are the segmentation and identification of bone, muscle and fat, and the computation of densitometric and geometric variables of each regional tissue type. Our system was validated against reference area and densitometric measurements over a set of test images and produced encouraging results.
Transmission of timing references to sub-picosecond precision over optical fiber

A fiber optic system was developed for the purpose of distributing precision timing reference signals to telescope subsystems that are physically separated by as much as 3 kilometers, while preserving the spectral purity and phase stability of a hydrogen maser source and while avoiding cycle ambiguities. The signals are transmitted via single-mode optical fiber to five locations on the site, each 1 to 3 kilometers away, where they are used as references for receiver local oscillators and other signal processing electronics; this imposes stringent requirements on phase stability. Phase jitter (defined here as the total phase noise integrated over offset frequencies above 1 Hz), was minimized by the careful selection of components and by standard phase- locked-loop techniques. Phase drift (phase noise at offsets of less than 1 Hz) is caused primarily by variation of the fiber's electrical length, and is accounted for by re- transmission from remote to master and accurate monitoring the round-trip delay. The system is capable of measuring path length changes as small as 0.1 picosecond. These measurements are not used for real-time correction, but instead they are applied during post processing of the astronomical data. This approach allows coherent interferometry at millimeter wavelengths. Two frequencies, 10 MHz and 500 MHz, are transmitted over one fiber, with their sum providing direct intensity modulation of a diode laser. The 10 MHz signal extends the cycle ambiguity to 100 nsec. A sample of the received 500 MHz is sent back on a separate fiber to the transmitting station where it is phase compared with the outgoing signal. A third signal at 1 Hz is transmitted separately, extending the ambiguity to 1 sec. The fiber length should be extendible to at least 10 km while achieving the same performance, although we have not tested this. Larger distances should be possible with lower-noise lasers. Lower timing noise could be achieved by increasing the reference frequency from 500 MHz to several GHz.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Effects of prescribed fire and fire surrogates on floral visiting insects of the blue ridge province in North Carolina

Pollination by insects in forests is an extremely important process that should be conserved. Not only do pollinating insects help to maintain a diversity of plants within forests, but they also aid in pollinating crops found near forested land. Currently, the effects of various forest management practices on floral visiting insect abundance or diversity is unknown, so we investigated how prescribed burning, mechanical shrub control, and combination of the two affected abundance of floral visiting insects. We caught 7921 floral visitors from four orders and 21 families. Hymenoptera was the most abundant and diverse order, with Halictidae being the most abundant family. A total of 45 species of Hymenoptera representing six families were captured. We caught seven families and 35 species of Lepidoptera, six families and 33 species of Coleoptera, and two families and 13 species of Diptera. Most floral visitors were captured in the mechanical shrub control plus prescribed burn treatments, while lower numbers were caught on the mechanical shrub control only, prescribed burn only and control treatments. Overall species richness was also higher on mechanical plus burn treatments. Total pollinator abundance and the abundance of most orders and families was correlated with decreased tree basal area and increased percent herbaceous plant cover. Our study shows that floral visitors increased in abundance and species richness most from forest disturbance that reduced the density of overstory trees and increased the amount of herbaceous plant growth.
Expeditious syntheses of (+/-)-5-oxosilphiperfol-6-ene and (+/-)-silphiperfol-6-ene.

Stereocontrolled syntheses of 5-oxosilphiperfol-6-ene (1) and silphiperfol-6-ene (2) have been accomplished in four and five steps, with overall yields of 32% and 26%, respectively, from 1-acetyl-3-methylcylopentene. The strategy features two pivotal reactions: (a) a Diels−Alder reaction between 1,3-dimethylcyclopentadiene and 1-acetyl-3-methylcyclopentene, which proceeds with remarkable regio-, endo-, and diastereofacial selectivities, and (b) an intramolecular Paterno−Buchi reaction to snap together the triquinane framework.
Home-Based Multidisciplinary Diagnosis and Treatment of Inner-City Elders With Dementia

The Memory and Aging Project Satellite (MAPS) of the Washington University Alzheimer's Disease Research Center was developed to meet the medical, social, and housing needs of minority and medically underserved elders with cognitive impairments. MAPS is located in the offices of the St. Louis Area Agency on Aging (AAA). This program provides multidisciplinary outreach, as well as home-based diagnosis, treatment, and case management. It differs from most other satellite programs in that it seeks to provide service to individuals who do not voluntarily seek help for dementia. Cognitively impaired clients had numerous, unmanaged medical conditions and social problems. Few clients were adequately served by health and social service systems. Despite recent contact, only 10% of clients received a formal diagnosis of dementia from a physician. Treatment was hampered by the absence or limitations of caregivers. Despite the complexities of these cases, the MAPS staff have been generally successful in addressing client problems.
Malignant PEComa of the skull base.

AbstractPerivascular epithelioid cell tumors (PEComas) are rare, usually benign lesions comprising a family of neoplasms including angiomyolipoma, lymphangioleiomyomatosis, clear cell “sugar” tumors, and clear cell myomelanocytic tumors. This report describes an apparent case of a malignant PEComa o
Downstream Development of the Gulf Stream from 68° to 55°W

Abstract Two CTD sections across the Gulf Stream at 68° and 55°W were acquired in late March of 1988 within 11 days of one another as part of an effort to look at downstream changes in the current. Using complementary current meter measurements, sections of total barotropic and geostrophic baroclinic velocity are constructed and used to calculate transport in potential density classes. Potential vorticity sections are presented for both locations, including the effects of planetary, stretching, and relative vorticity. The data are also used to examine the core properties of recently formed 18°Water at the two sections. It is found that: 1) water parcels in the exposed surface layers experience downstream density and potential vorticity changes consistent with surface forcing; 2) thermocline Gulf Stream transport is conserved downstream and below the exposed layers is conserved within individual density classes; 3) subthermocline Gulf Stream transport increases modestly at levels above the sill depth of th...
A Note on Minimum Variance Unbiased Estimation

The process of Rao–Blackwellization involves specification of a naive unbiased estimator of τ(θ) and then determination of its conditional expectation given a complete and sufficient statistic T for θ. This leads to the minimum variance unbiased estimator (MVUE) U ≡ U(T) for τ(θ). In some situations, however, a naive unbiased estimator of τ(θ) may not be an easy thing to come across. Theorem 2.1 fills an important void by formulating a new approach to find the MVUE for τ(θ) in a number of interesting situations where the customary Rao–Blackwellization technique may not be very simple to implement. The new approach is illustrated with the help of a series of interesting examples. Theorem 2.1 has its own limitation and we have highlighted that with an example.
Exactly soluble anharmonic potential models

Abstract The construction and exact quantum mechanical solution of anharmonic potential models is discussed. For low energy eigenvalues the proposed models simulate the usual quadratic-quartic potentials, but for high eigenvalues their properties are essentially those of the harmonic oscillator.
Arbitrariness and Causation in Classical Population Genetics

AbstractI criticize some arguments against the causal interpretability of population genetics put forward by Denis Walsh ([2007], [2010]). In particular, I seek to undermine the contention that pop...