cssi/SciSciGPT-SciSciNet huggingface dataset:
Generation of Microclimates From the Differential Decomposition of Textiles in North Central Florida

The analysis of textiles as trace evidence is an important area of focus in the field of forensic science, because enhanced understanding of the decomposition of textiles may point to more accurate methods for estimating the post mortem interval (PMI) of remains found in association with these materials. This research is especially crucial in areas with unique climates, like the state of Florida. This study examines the generation of microclimates from the differential decomposition of various textile types. This study hypothesized that the decomposition of textiles will generate microclimates with soil properties that differ from those of the surrounding environment, and that different types of textiles will create different microclimates as they decompose. Samples of cotton, UV-proofed cotton, polyester, cotton-polyester blended fabric, ripstop, and wool were buried at four sites on a property in North Central Florida for thirteen weeks, with measures of soil temperature, pH, and moisture level, and weather data collected weekly. Following burial, decomposition of each textile type was scored. Data collected were analyzed in R statistical software. Analysis indicated that the level of degradation differed by textile type but not by site. Textile presence, type of textile, and subsequent decomposition significantly impacted soil pH and moisture at all sites, but did not have a significant effect on soil temperature. The results of this study demonstrate that the decomposition of textiles can create diverse and unique microclimates in the soil environment. When found in association with human remains, presence and type of textile should be considered when estimating decomposition rates and the postmortem interval.
β-Trioxopyrrocorphins: pyrrocorphins of graded aromaticity

Octaethyltrioxopyrrocorphins unexpectedly show macrocycle-aromatic properties, even though they contain the macrocyclic π-system of the non-aromatic pyrrocorphins (hexahydroporphyrins). Two of the four possible triketone regioisomers were first reported in 1969 by one-pot oxidation of octaethylporphyrin but remained essentially unexplored since. We detail here the targeted preparation of the remaining two triketone isomers and the optical and NMR spectroscopic properties of all isomers. All four regioisomers possess unique electronic properties, including broadly varying degrees of diatropicity that were experimentally determined using 1H NMR spectroscopy and computationally verified. Structural patterns modulating the aromaticity were recognized. These differences highlight the regioisomerically differentiated influences of the three β-oxo-functionalities. We also present the solid state structure of the two most common isomers (in their free base form or as zinc complexes), allowing further conclusions to be made about the resonance structures present in these triketones. Remarkably, also, the halochromic properties of the triketones differ sharply from those of regular (hydro)porphyrins, providing further support for the proposed 16-membered, 18 π-electron aromatic ring-current. The work conceptually expands the understanding of tris-modified hydroporphyrinoid analogues and the factors that enable and control porphyrinoid aromaticity.
Surface architecture and proton conduction in SPVDF-co-HFP based nanocomposite membrane for fuel cell applications: Influence of aprotic solvent mixture

Abstract In the present study, the prime focus is to study the effect of a new solvent mixture on the formation of PVDF-co-HFP based nanocomposite membrane by solution casting method and their applicability to perform as a proton conducting membrane for fuel cell applications. A definite proportion two dipolar aprotic solvent mixture N-Methyl-2-pyrrolidone (NMP) and Acetonitrile (ACN) was used as the solvent mixture and it has been observed that the use of these solvents results in a porous structure with smaller micro domains within it, as evidenced from the FESEM micrographs. The mechanical resistance of the membranes also significantly improved with the change of solvent resulting in the formation of a ductile membrane. Incorporation of in-situ synthesized silanized silica nanoparticles into the polymer backbone following the sulfonation of the membranes using chlorosulfonic acid, also contributed in the improved physicochemical and the electrochemical properties with respect to higher water retention, better ion exchange capability (0.98 meq. g−1) and proton conductivities. Additionally, the silanized silica nanoparticles showed improved dispersibility within the polymer membrane thereby resulting in absorption of more sulfonic acid groups and shortened interchain separation distance which has been confirmed from XRD analysis. Thus, an interconnected proton conduction pathway which was formed, enhanced the proton conductivity to 0.113 S cm−1. Further, the barrier properties of the silica nanoparticles additionally suppressed the methanol crossover as compared with Nafion, while improving the membrane selectivity (3.65 × 104 S.scm−3).
III Light Beating Spectroscopy

Publisher Summary This chapter discusses light beating spectroscopy, which is a direct analog of the familiar mixing of a.c. electrical signals in nonlinear circuit elements. The aspect of light beating spectroscopy, the mixing of two narrowband optical components which produces an a.c. component in the photocurrent at the optical difference frequency, is extensively employed in the analysis of the mode structure of lasers. When light is diffracted by ultrasonic waves in a fluid, the diffraction maxima contain components whose frequency is shifted from that of the incident light by integral multiples of the ultrasonic frequency. The shifts are measured by mixing the diffracted light with the incident laser light. The light, which is scattered from a fluid, has spectral components which are shifted in frequency from the incident light by inelastic photon-phonon scattering. Light, which is scattered by small impurities in a moving fluid, will be Doppler shifted by an amount proportional to the local fluid velocity.
Effectiveness of Minocycline and Rifampin vs Chlorhexidine and Silver Sulfadiazine-Impregnated Central Venous Catheters in Preventing Central Line-Associated Bloodstream Infection in a High-Volume Academic Intensive Care Unit: A Before and after Trial

Background Use of chlorhexidine and silver sulfadiazine-impregnated (CSS) central venous catheters (CVCs) has not been shown to decrease the catheter-related bloodstream infection rate in an ICU. The purpose of this study was to determine if use of minocycline and rifampin-impregnated (MR) CVCs would decrease central line-associated bloodstream infection (CLABSI) rates compared with those observed with use of CSS-impregnated CVCs. Study Design A total of 7,181 patients were admitted to a 24-bed university hospital surgical ICU: 2,551 between March 2004 and August 2005 (period 1) and 4,630 between April 2006 and July 2008 (period 2). All patients requiring CVC placement in period 1 had a CSS catheter inserted, and in period 2 all patients had MR CVCs placed. Results Twenty-two CLABSIs occurred during 7,732 catheter days (2.7 per 1,000 catheter days) in the 18-month period when CSS lines were used. After the introduction of MR CVCs, 21 catheter-related bloodstream infections occurred during 15,722 catheter days (1.4 per 1,000 catheter days). This represents a significant (p Conclusions The CLABSI rate decreased more with the use of MR CVCs compared with CSS CVCs in an ICU where the CLABSI rate was already low. The types of organisms causing infection were similar. With continued use of MR-impregnated CVCs in our ICU in the subsequent 5 years, we have seen sustained low rates of CLABSIs.
Assertion-based encapsulation, object invariants and simulations

In object-oriented programming, reentrant method invocations and shared references make it difficult to achieve adequate encapsulation for sound modular reasoning. This tutorial paper surveys recent progress using auxiliary state (ghost fields) to describe and achieve encapsulation. Encapsulation is assessed in terms of modular reasoning about invariants and simulations.
Effects on promoter activity of common SNPs in 5' region of GABRB3 exon 1A.

Summary Purpose: The β3 subunit of the γ-aminobutyric acid type A receptors (GABAA–Rs) is an essential component of GABAA–Rs in fetal, perinatal, and adult mammalian brain. Various transcripts of the β3 subunit gene (GABRB3) produce various proteins with different N-termini. Rare variants in this N-terminus (exon 1A and exon 2) of GABRB3 protein segregate in affected family members of two multigeneration-multiplex families with remitting childhood absence epilepsy (rCAE), suggesting GABRB3 is a major Mendelian epilepsy gene for rare families with CAE. Therefore, the N-terminus of GABRB3 could be important for GABRB3 regulation in development, and its alteration could produce rCAE. Herein we determine if single nucleotide polymorphisms (SNPs) within the 1,148-bp region upstream from exon 1A influence the expression of GABRB3. Methods: We studied luciferase reporter expression for promoter activity, 1,148-bp upstream from exon 1A, using human embryonic kidney 293 cells. We generated constructs of the promoter region and compared different SNP haplotypes in 48 patients with rCAE. Next, we compared frequencies of rs20317, located in the core promoter region, and rs4906902, located in the enhancer region between 48 patients with rCAE and >500 healthy controls matched for ethnicity and ancestral origin. Key Findings: Highest luciferase expression occurred 230-bp upstream of exon 1A. The construct that excluded this region lost luciferase activity. Therefore, this region contains the core promoter of exon 1A. Allele C but not allele G (rs20317) significantly increased luciferase expression activity. Allele C creates binding motifs for cMYB and EGR-3. Longer constructs overlapping this region have a binding motif for REST (RE1-silencing transcription factor), a critical epigenetic modulator for neuronal genes. REST represses expression of neuronal genes in nonneuronal tissues, resulting in reduced luciferase expression activity. Even in the suppressed condition, the longer construct enhanced luciferase expression activity of the shorter construct, which excluded the distal end containing rs4906902. However, allele frequencies of rs20317 and rs4906902 were not significantly associated with 48 rCAE patients in comparison to >500 controls matched for ethnicity and ancestral origin. Significance: Common SNPs in the promoter region increase luciferase expression activity. An epigenetic modulator, REST, specifically alters expression of GABRB3 exon 1A transcripts, suggesting epigenetic regulation by REST dominantly controls the expression of GABRB3 variant 2 transcript in early life GABAA signaling. Abnormal epigenetic regulation could be involved in absence seizures.
Potent Topoisomerase I Inhibition by Novel Silatecans Eliminates Glioma Proliferation in Vitro and in Vivo

Although topoisomerase inhibitors, such as camptothecin and topotecan, have been widely used in the treatment of nonglial tumors, their application for gliomas has been limited by poor efficacy relative to toxicity that may in part reflect limited bioavailability and blood stability of these agents. However, the potential promise of this class of agents has fostered efforts to develop new, more potent, and less toxic inhibitors that may be clinically relevant. Using a cascade radical annulation route to the camptothecin family, we developed a series of novel camptothecin analogues, 7-silylcamptothecins ("silatecans"), that exhibited potent inhibition of topoisomerase I, dramatically improved blood stability, and sufficient lipophilicity to favor blood-brain barrier transit. We explored the efficacy of a series of these agents against a panel of five high-grade glioma cell lines to identify a promising compound for further preclinical testing. One of the most active agents in our systems (DB67) inhibited tumor growth in vitro with an ED50 ranging between 2 and 40 ng/ml, at least 10-fold more potent than the effects observed with topotecan, and at least comparable with those of SN-38, the active metabolite of CPT-11. Because DB67 also exhibited the highest human blood stability of any of the agents examined, this agent was then selected for in vivo studies. A dose-escalation study of this agent in a nude mouse U87 glioma model system demonstrated a concentration-dependent effect, with tumor growth inhibition at day 28 postimplantation (the day control animals began to require sacrifice because of large tumor size) of 61 +/- 7% and 73 +/- 3% after administration of DB67 doses of 3 and 10 mg/kg/day, respectively, for 5 days beginning on postimplantation day 7. Animals that continued treatment with 10 mg/kg/day in three additional 21-day cycles all remained progression free after >90 days of follow-up but later developed enlarging tumors after treatment was stopped. However, a slightly higher dose (30 mg/kg/day) induced complete tumor regression after only two cycles in all study animals and was effective even if treatment was delayed until large, bulky tumors had developed. Application of the 30 mg/kg/day dose to treat established intracranial glioma xenografts led to long-term (>90 day) survival in six of six animals, whereas all controls died of progressive disease (P < 0.00001). No apparent toxicity was encountered in any of the treated animals. In summary, the present studies indicate that silatecans may hold significant promise for the treatment of high-grade gliomas and provide a rationale for proceeding with further preclinical evaluation of their efficacy and safety versus commercially available camptothecin derivatives.
A discriminative linear regression approach to OCR adaptation

This paper presents a new discriminative linear regression approach to adaptation of a discriminatively trained prototype-based classifier for Chinese OCR. A so-called sample separation margin based minimum classification error criterion is used in both classifier training and adaptation, while an Rprop algorithm is used for optimizing the objective function. Formulations for both model-space and feature-space adaptation are presented. The effectiveness of the proposed approach is confirmed by experiments for adaptation of font styles and low-quality text, respectively.
Survival of Patients Who Have Undergone Allogeneic Bone Marrow Transplantation: The Relative Importance of In-Hospital Lay Care-Partner Support

Data from 131 consecutive adult patients who underwent allogeneic bone marrow transplantation (BMT) at a tertiary care center from 1997 to 1999 suggest that the presence of an in-hospital lay care-partner during the patients' hospital stay is a powerful prognostic variable of survival. One year after the transplant, 75% of the patients with a lay care-partner were alive versus 26% of those without a care-partner. A multivariable survival analysis revealed not having an in-hospital lay care-partner as a significant independent risk factor for death (p <.001). This relationship held when adjusting for other such risk factors: i.e., primary diagnosis, disease status, and source of donor marrow. The idiosyncratic nature and importance of partnered relationships for survival in allogeneic BMT and the need to intervene and improve outcomes for patients are discussed with regard to future research and clinical programs.
Attention is critical for spatial auditory object formation.

The precedence effect provides a novel way to examine the role of attention in auditory object formation. When presented with two identical sounds from different locations separated by a short stimulus onset asynchrony (SOA), listeners report a single auditory object at the location of the lead sound. When the SOA is above the echo threshold, listeners report hearing two auditory objects with different locations. Event-related potential (ERP) studies have shown that the number of perceived auditory objects is reflected in an object-related negativity (ORN) 100–250 ms after onset and in a posterior late positivity (LP) 300–500 ms after onset. In the present study, we tested whether these ERP effects are modulated by attention by presenting lead/lag click pairs at and around listeners’ echo thresholds, while in separate blocks the listeners (1) attended to the sounds and reported whether the lag sound was a separate source, and (2) performed a two-back visual task. When attention was directed away from the sounds, neither the ORN nor the LP observed in the attend condition was evident. Instead, unattended click pairs above the echo threshold elicited an anterior positivity 250–450 ms after onset. However, an effect resembling an ORN was found in comparing the ERPs elicited by unattended click pairs with SOAs below the attended echo threshold, indicating that the echo threshold may have been lowered when attention was directed away from the sounds. These results suggest that attention modulates early perceptual processes that are critical for auditory object formation.
Dual DNA Binding Specificity of ADD1/SREBP1 Controlled by a Single Amino Acid in the Basic Helix-Loop-Helix Domain

Adipocyte determination- and differentiation-dependent factor 1 (ADD1), a member of the basic helix-loop-helix (bHLH) family of transcription factors, has been associated with both adipocyte differentiation and cholesterol homeostasis (in which case it has been termed SREBP1). Using PCR-amplified binding analysis, we demonstrate that ADD1/SREBP1 has dual DNA sequence specificity, binding to both an E-box motif (ATCACGTGA) and a non-E-box sequence previously shown to be important in cholesterol metabolism, sterol regulatory element 1 (SRE-1; ATCACCCCAC). The ADD1/SREBP1 consensus E-box site is similar to a regulatory sequence designated the carbohydrate response element, defined by its ability to regulate transcription in response to carbohydrate in genes involved in fatty acid and triglyceride metabolism in liver and fat. When expressed in fibroblasts, ADD1/SREBP1 activates transcription through both the carbohydrate response E-box element and SRE-1. Substitution of an atypical tyrosine in the basic region of ADD1/SREBP1 to an arginine found in most bHLH protein causes a restriction to only E-box binding. Conversely, substitution of a tyrosine for the equivalent arginine in another bHLH protein, upstream stimulatory factor, allows this factor to acquire a dual binding specificity similar to that of ADD1/SREBP1. Promoter activation by ADD1/SREBP1 through the carbohydrate response element E box is not sensitive to the tyrosine-to-arginine mutation, while activation through SRE-1 is completely suppressed. These data illustrate that ADD1/SREBP1 has dual DNA sequence specificity controlled by a single amino acid residue; this dual specificity may provide a novel mechanism to coordinate different pathways of lipid metabolism.
Mentoring Interdisciplinary Undergraduate Courses

In this chapter, I discuss the special needs and opportunities for effective faculty and graduate-student mentoring of undergraduates in an interdisciplinary model. These undergraduates are enrolled in large science-based, interdisciplinary, introductory (SBII) courses. I derived the commentary from five years of experience as the course director for the two-semester sequence—Introduction to Global Change, Part I: Physical Impacts and Part II: Human Impacts—at the University of Michigan. Although this model is specific with regard to topic and campus location, any interdisciplinary faculty team can apply the lessons learned and possible implementation strategies. New experiments with introductory science curricula, such as the University of Michigan’s Global Change courses, are being conducted for two principal reasons. First, these courses are influential in determining students’ career and academic choices, often providing the final opportunity for certain students to gain a basic appreciation for science and the scientific method as part of their general education. Second, past assessments in many disciplines have shown that students can sometimes be permanently alienated from science by traditional courses that emphasize rote learning. In response to these concerns, extensive efforts were made during the past decade to reform introductory curricula in mathematics (Artique, 1999), chemistry (Lloyd, 1994), physics (Physics Education Research, 1999), biology (Coalition for Education in the Life Sciences, 1999), and other disciplines, as well as to develop new interdisciplinary courses, designed to be broadly accessible to and appealing for first-year students. The mentoring in these classes is a key source of motivation for students to continue to study science.
Simultaneous imaging of cortical hemodynamics and blood oxygenation change during cerebral ischemia using dual-wavelength laser speckle contrast imaging

A dual-wavelength laser speckle contrast imaging technique (DW-LSCI) is presented for simultaneous imaging of cerebral blood flow and hemoglobin oxygenation changes at high spatiotemporal resolutions. Experimental validation was performed using a rat transient forebrain ischemia model. The results showed that DW-LSCI was able to track detailed hemodynamic and metabolic changes induced by ischemia, i.e., decreased oxy- and total hemoglobin concentrations and blood flow as well as increased deoxy-hemoglobin concentration in the downstream regions, thus allowing us to distinguish cerebral arterial and venous flows. Simultaneous cerebral blood flow and oxygenation imaging at high spatiotemporal resolutions is crucial to the understanding of neural process and brain functions.
Morphology of human neutrophils: A comparison of cryofixation, routine gluteraldehyde fixation, and the effects of dimethyl sulfoxide

Cell shape and density are critical to the evaluation of neutrophil function and/or activation. Dimethyl sulfoxide-cryofixation-freeze-substitution processing (DCF) instantly preserves cell processes and ultrastructural elements with fewer artifacts than routine chemical fixation with glutaraldehyde and postfixation osmium tetroxide (GO). This study morphometrically examined density-separated neutrophils to assess differences in DCF and GO processing procedures and studied the effect of dimethyl sulfoxide followed by GO fixation (DGO) on morphology. Fifteen consecutive neutrophils were analyzed using computerized planimetry for differences in DCF v. GO treatments (n = 4) and DGO v. GO treatments (n = 4). Cryofixed and DGO-fixed cells were significantly rounder than GO cells which had a more irregular surface with membrane projections. The cell volume of GO cells was 27-30% smaller than in DCF or DGO processing, while the surface area was similar. The increased volume in DCF and DGO cells did not appear to be due to abnormal cell swelling, since membranes, nuclear envelope, and mitochondrial cristae were more intact than in GO cells. Preservation of mitochondria as well as endocytic caveolae with a subplasmalemmal coating was best in DCF samples, moderate in DGO, and poorest in GO. Morphometric data showed that the nuclear compartment was 22% smaller, while the cytoplasm (and its associated compartments) was 29% smaller in GO compared to DCF-processed neutrophils. This was consistent with the more dense cytoplasm in GO cells. Pretreatment of neutrophils with dimethyl sulfoxide (DMSO) resulted in volume preservation and improved the morphology of GO fixation. In summary, DCF appears to be an excellent method for preserving neutrophil membranes and cytoplasmic organelles (particularly mitochondria), and prevents a number of artifacts caused by routine GO fixation. Morphology can also be improved by using DMSO in conjunction with GO.
The stereochemistry of hydrogen transfer to NADP+ by enzymes acting upon stereoisomeric substrates

Abstract The stereochemistry of hydrogen transfer from estradiol-17α and estradiol-17β to NADP + in the presence of chicken liver estradiol-17α and estradiol-17β dehydrogenases was found in both cases to involve the 4-pro-S proton of the pyridine nucleotide. One of these enzymes must therefore use the stereochemically less favorable mode of interaction of steroid with coenzyme.
Present status and future development of US federal standards for HF communications

This paper summarizes the status of existing US HF federal standards, the current and future work in the development of additional US federal standards, and identifies issues as to how these federal HF standards relate to international standards activities within NATO and the International Telecommunication Union-Radiocommunication sector (ITU-R).
Photoinitiator-free synthesis of endothelial cell-adhesive and enzymatically degradable hydrogels.

Abstract We report on a photoinitiator-free synthetic method of incorporating bioactivity into poly(ethylene glycol) (PEG) hydrogels in order to control physical properties, enzymatic biodegradability and cell-specific adhesiveness of the polymer network, while eliminating the need for UV-mediated photopolymerization. To accomplish this, hydrogel networks were polymerized using Michael addition with four-arm PEG acrylate (10 kDa), using a collagenase-sensitive peptide (CSP) as a crosslinker, and introducing an endothelial cell-adhesive peptide either terminally (RGD) or attached to the crosslinking peptide sequence (CSP-RGD). The efficiency of the Michael addition reactions were determined by nuclear magnetic resonance and Ellman’s assay. Successful decoupling of cell adhesivity and physical properties was demonstrated by quantifying and comparing the swelling ratios and Young’s moduli of various hydrogel formulations. Degradation profiles were established by incubating functionalized hydrogels in collagenase solutions (0.0–1.0 μg ml−1), demonstrating that functionalized hydrogels degraded at a rate dependent upon collagenase concentration. Moreover, it was shown that the degradation rate was independent of CSP-RGD concentration. Cell attachment and proliferation on functionalized hydrogels were compared for various RGD concentrations, providing evidence that cell attachment and proliferation were directly related to relative amounts of the CSP-RGD combination peptide. An increase in cell viability was achieved using Michael addition techniques when compared to UV polymerization, and was assessed by a LIVE/DEAD fluorescence assay. This photoinitiator-free method shows promise in creating hydrogel-based tissue engineering scaffolds allow for decoupled cell adhesivity and physical properties and that render greater cell viability.
Site-specific labeling of proteins with NMR-active unnatural amino acids

A large number of amino acids other than the canonical amino acids can now be easily incorporated in vivo into proteins at genetically encoded positions. The technology requires an orthogonal tRNA/aminoacyl-tRNA synthetase pair specific for the unnatural amino acid that is added to the media while a TAG amber or frame shift codon specifies the incorporation site in the protein to be studied. These unnatural amino acids can be isotopically labeled and provide unique opportunities for site-specific labeling of proteins for NMR studies. In this perspective, we discuss these opportunities including new photocaged unnatural amino acids, outline usage of metal chelating and spin-labeled unnatural amino acids and expand the approach to in-cell NMR experiments.
Management of inflammatory carcinoma of breast with combined modality approach - an update.

Thirty-two patients with inflammatory breast cancer were treated with a combined modality approach consisting of combination chemotherapy with fluorouracil, doxorubicin hydrochloride, and cyclophosphamide, followed by radiation therapy. The disease-free interval and survival of this group were compared with 32 patients with inflammatory breast cancer treated with irradiation without systemic therapy at our institution in the past. In the actuarial median follow-up of 62 months (range 42+ to 76+ months) of study, 11 patients in combined modality group and three patients in the irradiation group were free of disease. Overall median disease-free interval was 22.8 months for the combined modality group and nine months for the irradiation group, and 30.1 months and 18 months, respectively. The median disease-free interval of patients less than 50 years of age was 19 months for the combined modality group and nine months for the irradiation group; median survival was 24 months for both subgroups. Forty percent of the patients under 50 years of age in the combined modality group and 7% in the irradiation group had recurrence of central nervous system disease. Of the patients greater than of equal to 50 years of age, the median disease-free interval was 32.1 months for the combined modalitymore » group and nine months for irradiation group; median survival was 42 months and 18 months, respectively. The combined modality approach has resulted in improved disease-free interval of patients less than 50 years of age, but survival of this subgroup was not significantly improved possibly because of the high incidence of central nervous system disease recurrence. This treatment was effective in prolonging the disease-free interval and survival of patients greater than or equal to 50 years of age, with an estimated 45% of the patients surviving free of disease beyond 42 months.« less
Air-Sea Momentum Transfer by Means of Short-Crested Wavelets

Abstract Recent laboratory studies of Okuda and others revealed shear stress “spikes” over wavelet crests as the principal instruments of air-sea momentum transfer. Examination of other laboratory evidence shows that sharp local intensifications of skin friction is a characteristic of reattaching flow in three-dimensional separation only. Flow reattachment over a downwind wavelet crest ensures the coincidence of high shear stress and downwind orbital velocity, resulting in energy input to the fluctuating motion, i.e., a coupling of the wavelets to the wind. Such coupling is shown to occur over short-crested wavelets at a specific waveheight-to-wavelength ratio. Under the shear stress spikes a thin vertical layer develops on the water surface, which rides over the essentially irrotational motion of the wavelets. Thickening of the vortical layer over the windward face of a wavelet causes a positive pressure perturbation in quadrature with downward vertical velocity, which tends to transfer energy to the wav...
Rheological behavior of carbon nanotube-alumina nanoparticle dispersion systems

Abstract In this work, Al2O3 nanoparticle and CNT–Al2O3 nanoparticle suspensions were studied. Both Al2O3 nanoparticle and CNT–Al2O3 nanoparticle systems exhibit shear-thinning behavior. The viscosities increase monotonically with the suspension solids loading. For the 40 vol.% solids loading suspension, CNT effect on the viscosity is not substantial until the content is ≥ 1.3 vol.%. The suspension yield stress to flow provides a measure of the particle–particle networking in the suspension. With the adsorbed poly(acrylic acid) (PAA) layer on the particle surface, substantial colloidal interactions are observed when the solids loading is > 35 vol.% and the CNT content is > 1.3 vol.%. Storage modulus and loss modulus can be used to understand the relative magnitude of the viscoplastic behavior and the elastic behavior of the suspension as well as the transition between the two. The relative magnitude of the dynamic modulii is a strong function of the solids loading and the CNT content.
The HMO Backlash — Righteous or Reactionary?

The membership of health maintenance organizations (HMOs) now exceeds 50 million people and may grow by an additional 50 million by the year 2000. But all is not well in HMO-land. An angry and determined backlash is spreading across the nation. In 1996 alone, 1000 pieces of legislation attempting to regulate or weaken HMOs were introduced in state legislatures, and 56 laws were passed in 35 states. The backlash movement brings together patients who complain of services denied and physicians who are suffering the loss of autonomy and income.1 There are several manifestations of the backlash: federal and state legislation, . . .
An Evolutionarily Conserved Innate Immunity Protein Interaction Network

The innate immune response plays a critical role in fighting infection; however, innate immunity also can affect the pathogenesis of a variety of diseases, including sepsis, asthma, cancer, and atherosclerosis. To identify novel regulators of innate immunity, we performed comparative genomics RNA interference screens in the nematode Caenorhabditis elegans and mouse macrophages. These screens have uncovered many candidate regulators of the response to lipopolysaccharide (LPS), several of which interact physically in multiple species to form an innate immunity protein interaction network. This protein interaction network contains several proteins in the canonical LPS-responsive TLR4 pathway as well as many novel interacting proteins. Using RNAi and overexpression studies, we show that almost every gene in this network can modulate the innate immune response in mouse cell lines. We validate the importance of this network in innate immunity regulation in vivo using available mutants in C. elegans and mice.
TQM/CQI effectiveness at team and departmental levels

Abstract Structured interviews regarding continuous quality improvement (CQI) efforts were conducted with team leaders and department heads at a large medical center. The purpose of the interviews was to identify factors that were commonly associated with effective improvement efforts. Six factors were significantly related to team effectiveness: team leader attitude toward CQI, team leader skills and understanding of CQI, team CQI skills, team leader attendance in statistical process control (SPC) training, team complexity, and goal specificity. Factor analysis suggested that goal specificity, team complexity, and team leader attendance in SPC training were most associated with effective improvement efforts. For departments, only department head attitude toward CQI was significantly related to effectiveness of improvement efforts. Implications of these and other fundings are discussed, and directions for future research are suggested.
Intuition: Its Powers and Perils

One of the biggest revelations of recent psychological science is the two-track human mind, which features not only a deliberate, self-aware “high road” but also a vast, automatic, intuitive “low road.” Through experience, we learn associations that provide fast and frugal intuitions that enable instantaneous social judgments and the pattern recognition that marks acquired expertise. But as studies of implicit prejudice and intuitive fears illustrate, unchecked gut feelings can also lead us astray. Intuition's powers and perils appear in various realms, from sports to business to clinical and interviewer judgments.
Absolute Isotopic Abundance Ratios and Atomic Weight of Magnesium.

Absolute values have been obtained for the isotopic abundance ratios of magnesium, using surface emission mass spectrometry. Samples of known isotopic composition, prepared from nearly pure separated magnesium isotopes, were used to calibrate the mass spectrometers. The resulting absolute values are 25Mg/24Mg = 0.12663 ±0.00013 and 26Mg/24Mg = 0.13932 ± 0.00026, yielding an atomic weight (12C = 12) of 24.30497 ±0.00044. The indicated uncertainties are overall limits of error based on 95 percent confidence limits for the mean and allowances for effects of known sources of possible systematic error.
The OSCE: A Pan‐European Society in the Making?

Abstract This article applies an English School analysis of international society to the Organization for Security and Cooperation in Europe (OSCE). It argues that in a post‐enlargement Europe, the OSCE has a continuing role to play in socializing its members into norms and values consistent with a regional international society despite its lack of legal enforcement instruments, and the frequent divergence of its participating states from the rules and principles of collective engagement intrinsic to the Helsinki process. In so doing, the OSCE contributes to a thin–thick continuum of international society in a manner that is functionally and structurally relevant.
Changing contraceptive usage intentions: a test of the Fishbein model of intention.

This paper tests Fishbeins criteria for changing contraceptive usage intentions. The Fishbein model of intention suggests that intention may change as a consequence of change in either a related attitudinal or normative component. The study hypothesizes that interaction to use a contraceptive will change if the attitude toward using the contraceptive or normative beliefs about using the contraceptive has a significant influence on the prediction of the usage intention and if that component has been significantly altered by a change message. The messages advocated 1 of 3 contraceptive techniques: 1) males were advised to use condoms 2) males were advised to rely on their partners use of oral contraceptives or 3) females were advised to use oral contraceptives. 6 multiple regression analyses were carried out on users and nonusers of each of the 3 contraceptive usage intentions. Message induced attitude changes among condom nonusers male pill nonusers male pill users and female pill nonusers. Contraceptive usage intention changed only in the 2 conditions where the models requirements for change were present. The pattern of change agreed with Fishbeins suggestion and provided moderate support for the intention model and its application to intention change in health care settings.
Retention of iron oxide particles by stainless steel and magnetite magnetic matrix elements in high-gradient magnetic separation

Abstract The retention performances of a novel 80 wt% magnetite‐silica composite HGMS matrix element and a traditional stainless steel wool HGMS matrix element were compared. Breakthrough and ultimate (strictly magnetic) retention experiments were carried out at different feed concentrations, flow velocities, and magnetic field intensities with an aqueous slurry containing iron oxide (Fe2O3) particles. Results from the ultimate retention experiments were also compared to those obtained from a potential flow model. Overall, when supported by silica in the form of the 80 wt% magnetite‐silica composite, magnetite was about 30 to 40% as effective as stainless steel in retaining iron oxide, which was quite encouraging when considering that the magnetic saturation of magnetite is about five times smaller than that of stainless steel. Magnetite is also less expensive than stainless steel wool, even when encased in silica gel, which makes its use as an HGMS matrix element even more attractive for certain applicat...
Higher-order processes in electron-ion collisions

Abstract Electron-ion collision processes, together with ion-ion collisions, are of much current interest in connection with astrophysical and fusion plasma applications. The spectral line intensities and profiles observed can be analyzed in terms of the atomic cross-sections and reaction rates; information on the plasma density, composition, temperature, etc., is thereby obtained. More recently, several beautiful laboratory experiments have been carried out with highly-charged ionic beams, which interact with electrons in a crossed-beam arrangement or in a merged-beam configuration. In particular, both experimental and theoretical efforts have been directed to the study of higher-order effects which are invariably associated with intermediate resonances. As a result of the presence of many resonance states, these higher-order effects become important and often dominate the cross-sections. In addition, collision experiments can be performed with or without an external field imposed in the scattering region. The effect of external fields on the cross-section can be very large, especially when high Rydberg intermediate resonance states are involved. We summarize the various collision processes (excitation, ionization and capture) and discuss those theoretical problems which require improved experimental testing.
Reactions of Hf+, Ta+, and W+ with O2 and CO: Metal carbide and metal oxide cation bond energies

Abstract The reactions of Hf+, Ta+, and W+ with O2 and CO are studied as a function of translational energy in a guided ion beam tandem mass spectrometer. All three reactions with O2 form diatomic metal oxide cations in exothermic reactions that occur at the collision rate. In the CO systems, formation of both diatomic metal oxide and metal carbide cations is observed to be endothermic. The energy-dependent cross sections in the latter systems are interpreted to give 0 K bond energies (in eV) of D0(HfC+) = 3.19 ± 0.03, D0(TaC+) = 3.79 ± 0.04, D0(WC+) = 4.76 ± 0.09, D0(HfO+) = 6.91 ± 0.11, D0(TaO+) = 7.10 ± 0.12, and D0(WO+) = 6.77 ± 0.07. The present experimental values for TaO+ and WC+ agree well with literature thermochemistry, those for HfO+ and WO+ refine the available literature bond energies, and those for HfC+ and TaC+ are the first measurements available. The nature of the bonding in MO+ and MC+ is discussed and compared for these three metal ions and analyzed using theoretical calculations at a B3LYP/HW+/6-311+G(3df) level of theory. Bond energies for all MO+ and MC+ species are calculated using geometries calculated at this level and single point energies determined at B3LYP, CCSD, CCSD(T), QCISD, and QCISD(T) levels of theory with the same basis set. Reasonable agreement between the theoretical and experimental bond energies for the three metal oxide and three metal carbide cations is found. Potential energy surfaces for reaction of the metal cations with CO are also calculated at the B3LYP level of theory and reveal additional information about the reaction mechanisms.
Tectonic implications for the along-strike variation of the Peninsular Ranges batholith, southern and Baja California

The Jurassic-Cretaceous Peninsular Ranges batholith of southern and Baja California exhibits several along-strike variations that are most pronounced across the Agua Blanca fault. These variations include differences in the age of magmatism, degree of inheritance in zircons, depositional environment of volcanic strata, extra-arc basin geography, lateral extent of continentally derived flysch strata, and the structures attending juxtaposition of the two segments with the North American continental margin and with each other. We propose that these variations, when taken together, imply that the two segments of the western zone currently juxtaposed by the active Agua Blanca fault were accreted to North America diachronously and did not share a common history prior to the late Early Cretaceous. The Santiago Peak arc segment north of the fault developed on oceanic lithosphere juxtaposed with the continental margin prior to and during arc magmatism. Conversely, the Alisitos arc segment developed on oceanic lithosphere exotic to North America prior to accretion at 115‐108 Ma. If this model is correct, it implies that the Agua Blanca fault initiated as a transpressional continuation of the suture joining the latter arc segment to the continent and that a large portion of the forearc that existed between them was subducted.
Overbounding position errors in the presence of carrier phase multipath error model uncertainty

In this paper, a methodology is developed to overbound the error in position estimation for carrier phase navigation systems subject to multipath error mis-modeling. In high accuracy and high integrity applications, carrier phase positioning systems with cycle resolution usually rely on time-filtering, in many cases using Kalman filters. Naturally, for a computed integrity risk to be meaningful, it must be guaranteed that the predicted state estimation error covariance always bounds the true covariance. The Kalman filter ensures state error covariance bounding provided that the measurement errors and system dynamics are accurately modeled. However, uncertainties in the dynamic model of the multipath error states always exist. In response, the focus of this work is to quantify and bound position estimate errors subject to uncertainties associated with the time correlation of multipath error.
Developing Sustainable Peripheries: The Limits of Citizenship in Guatemala City

In March 1984 approximately 800 families squatted on previously unoccupied lands on the edge of Guatemala City in an area known as El Mezquital. In the following months, squatters continued to arrive, eventually forming a community of more than 25,000. This was the first major organized act of squatting that successfully established a community in the city since 1976. Dozens of other "land invasions"-to employ the term most commonly used in Guatemala-had been broken up by the police in the early 1980s (CITGUA, 1991: 70). However, following the success of Mezquital, other squatters have established communities throughout the city.1 Although the Guatemalan state still forcefully breaks up land seizures, many of these settlements in the past 16 years have slowly been transformed into neighborhoods. The increase in urban squatting has come at a crucial point in Guatemalan history. Since 1984 Guatemala has experienced fundamental changes in its body politic. In the transition from dictatorship to "democracy" and from 35 years of civil war to "peace," new spaces have opened up for marginalized actors to have a political voice.2 As the case of urban squatting makes clear, these new spaces are important. They are not, however, without their limits and silences. The squatters have benefited, particularly in the 1980s, from the spotlight provided by the presence of international development organizations and the emergence of a relatively independent press, articulating a strong critique of the conditions under which they live. Nevertheless, they slowly lose the ability to voice their concerns. This silencing occurs, at least in part, because of modern "development" institutions providing crucial
Exchange rings, units and idempotents

An associative ring R with identity is semiperfect if and only if every element of R is a sum of a unit and an idempotent, and R contains no infinite set of orthogonal idempotents. A ring which contains no infinite set of orthogonal idempotents is an exchange ring if and only if every element is a sum of a unit and an idempo-tent
Chlorine-36 and the initial value problem

Chlorine-36 is a radionuclide with a half-life of 3.01×105a. Most 36Cl in the hydrosphere originates from cosmic radiation interacting with atmospheric gases. Large amounts were also produced by testing thermonuclear devices during 1952–58. Because the monovalent anion, chloride, is the most common form of chlorine found in the hydrosphere and because it is extremely mobile in aqueous systems, analyses of both total Cl– as well as 36Cl have been important in numerous hydrologic studies. In almost all applications of 36Cl, a knowledge of the initial, or pre-anthropogenic, levels of 36Cl is useful, as well as essential in some cases. Standard approaches to the determination of initial values have been to: (a) calculate the theoretical cosmogenic production and fallout, which varies according to latitude; (b) measure 36Cl in present-day precipitation and assume that anthropogenic components can be neglected; (c) assume that shallow groundwater retains a record of the initial concentration; (d) extract 36Cl from vertical depth profiles in desert soils; (e) recover 36Cl from cores of glacial ice; and (f) calculate subsurface production of 36Cl for water that has been isolated from the atmosphere for more than one million years. The initial value from soil profiles and ice cores is taken as the value that occurs directly below the depth of the easily defined bomb peak. All six methods have serious weaknesses. Complicating factors include 36Cl concentrations not related to cosmogenic sources, changes in cosmogenic production with time, mixed sources of chloride in groundwater, melting and refreezing of water in glaciers, and seasonal groundwater recharge that does not contain average year-long concentrations of 36Cl.
Design changes in SNAP-8 for reduced reactor operating temperatures

SNAP-8 mercury Rankine system performance data, investigating design change for reduced reactor operating temperatures