cssi/SciSciGPT-SciSciNet huggingface dataset:
Abstract 464: Arginase Promotes Vascular Smooth Muscle Cell Proliferation and Neointima Formation

Arginase is the central enzyme of the hepatic urea cycle catabolizing L-arginine to L-ornithine which is subsequently metabolized to polyamines and L-proline. We recently discovered that vascular smooth muscle cells (SMC) express arginase activity and that arginase stimulates the synthesis of polyamines from L-arginine. Since polyamines are essential for cell growth, we examined the role of arginase in regulating vascular SMC proliferation. Treatment of cultured rat aortic SMC with platelet-derived growth factor (PDGF; 0.1–30 nM for 0–24h) stimulated arginase activity in a concentration and time-dependent manner. The increase in arginase activity by PDGF was associated with the selective expression of arginase I mRNA and protein, and a two-fold increase in intracellular polyamine concentration. In contrast, arginase II expression was unaffected by PDGF. Interestingly, the highly specific arginase inhibitors, (S)-2-boronoethyl)-L-cysteine (BEC; 100 μM) and N-hydroxy-nor-L-arginine (100 μM), inhibited the PDGF-mediated increases in polyamine levels, DNA synthesis, and cell proliferation. The inhibitory effect on SMC growth by the arginase inhibitors was reversed by the exogenous addition of polyamines (10 μM). To investigate the functional effect of arginase in vivo , we performed carotid artery balloon injury in rats. Ribonuclease protection assays, western blots, and immunohistochemistry revealed that arterial injury induced a rapid (1 day) expression of arginase I mRNA and protein in vascular SMC that persisted for nearly two weeks. Perivascular application of BEC (1 mg) via a pluronic gel immediately following balloon injury markedly attenuated neointima formation two weeks after injury (intima/media ratio, 0.213 ± 0.096 versus 0.588 ± 0.049 in control). Furthermore, PCNA-staining indicated that BEC inhibited DNA synthesis two days after arterial injury (3.44 ± 0.66 % versus 16.32 ± 0.97% in control). In conclusion, these results demonstrate that PDGF and arterial injury stimulate arginase I gene expression and that arginase I promotes vascular SMC growth and neointima formation by increasing cellular polyamine levels. Arginase I represents a potentially novel therapeutic target for limiting the vascular response to injury.
Astrocytes and the Synucleinopathies

α-Synuclein is an abundantly expressed protein located in the neuronal synapse which accumulates in Lewy body inclusions and synaptic aggregates in neurodegenerative diseases. Although evidence indicates that oligomeric α-synuclein can stimulate neurodegeneration, and α-synuclein amyloid fibrils can spread in a prion-like manner, the initial cause of α-synuclein dysregulation is uncertain. α-Synuclein released from the neuronal presynaptic terminal can accumulate in astrocytes early in disease progression and astrocyte dysfunction has been observed in the same disease phase. Astrocytes provide homeostatic balance to the brain parenchyma through release of neuroprotective factors and clearing of waste products to the vasculature, and astrocytic dysfunction has been shown to cause neuronal cell death. Like protein aggregation in other proteinopathies, such as neurofibrillary tangles and β-amyloid plaques, evidence is emerging that accumulation of abundantly expressed neuronal proteins could be a by-product of initial non-neuronal cellular degeneration. This review examines interactions between α-synuclein and astrocytes with a consideration of an astrocytic cause of synucleinopathy
The Virtual Care Farm: A Preliminary Evaluation of an Innovative Approach to Addressing Loneliness and Building Community through Nature and Technology

Social relationships and engagement are critically important to well-being in later life and have been found to be strongly correlated with isolation and loneliness. Addressing loneliness has emerg...
Practice Patterns of Pneumocystis Pneumonia Prophylaxis in Connective Tissue Diseases: A Survey of Infectious Disease Physicians

Background Immunosuppressive therapy for connective tissue diseases (CTDs) increases risk for opportunistic infections including Pneumocystis pneumonia (PCP). High mortality rates are reported in CTD patients with PCP, which suggests a potential need for prophylaxis, but indications remain poorly defined. Wide variations in the use of PCP prophylaxis among rheumatologists have been documented. This study evaluated PCP prophylaxis patterns for CTD patients among infectious disease (ID) physicians. Methods An electronic survey was emailed to 1264 adult ID physicians who are members of the Infectious Diseases Society of America Emerging Infections Network. Results Six hundred thirty-one physicians responded to the survey. Respondents to the survey were more likely to work in academics (P = .02) and be early (<5 years) or late (≥25 years) in their careers (P = .0002). Forty-three percent (n = 269) made no recommendations for PCP prophylaxis in non-HIV patients. Of the 362 respondents who did make such recommendations, the greatest consensus for disease-based prophylaxis was for granulomatosis with polyangiitis (53%). For therapy-based prophylaxis, corticosteroids ≥20 mg/d was the most frequently cited indication (87%). Surrogate laboratory markers to aid in decisions about prophylaxis were not routinely used (21%). Although the majority recommended discontinuation of PCP prophylaxis with tapering of corticosteroids (65%), there was variability in the specific dose. Eighty-nine percent of respondents felt that guidelines about PCP prophylaxis would be helpful. Conclusions There is little consensus about PCP prophylaxis in CTDs among ID physicians. Guidelines for PCP prophylaxis would be helpful when caring for these complex patients.
Advancing Variable Star Astronomy: The Centennial History of the American Association of Variable Star Observers

Preface Part I. Pioneers in Variable Star Astronomy Prior to 1909: 1. The emergence of variable star astronomy - a need for observations 2. A need for observers Part II. The Founding of the AAVSO - The William Tyler Olcott Era: 3. The amateur's amateur 4. Amateurs in the service of science Part III. The Leon Campbell Era: 5. Leon Campbell to the rescue 6. Formalizing relationships 7. The Pickering Memorial Endowment 8. Fading of the Old Guard 9. Growing pains and distractions Part IV. The Service Bureau - The Margaret Mayall Era: 10. Learning about independence 11. Eviction from Harvard College Observatory 12. Actions and reactions 13. In search of a home 14. Survival on Brattle Street 15. AAVSO achievements 16. Breathing room on Concord Avenue Part V. Analysis and Science: The Janet Mattei Era: 17. The growth of a director 18. Learning the ropes the hard way 19. Managing with renewed confidence 20. Expanding the scientific charter Part VI. Accelerating Observational Science - The Arne Henden Era: 21. Bridging the gap 22. Accelerating the science - the Henden era begins Epilogue Appendices Index.
Fifty Years of Film 2: Accomplices: Arturo Ripstein and Paz Alicia Garciadiego

In this interview, Arturo Ripstein and screenwriter Paz Alicia Garciadiego discuss their first collaborations, including El imperio de la fortuna (1986), Mentiras piadosas (1989), La mujer del puerto (1991), Principio y fin (1993), and the making of El evangelio de las maravillas (1998). Specifically, they describe the process of writing screenplays and transforming them into films. They also delve into a discussion of the melodrama and Arturo Ripstein describes how, while making Mentiras Piadosas and contemplating the significance of jealousy in the film, discovered his preference for filming long sequences.
Comment: A role of Language in Infant Emotion Concept Acquisition:

Ruba and Repacholi (2020) review an important debate in the emotion development literature: whether infants can perceive and understand facial configurations as instances of discrete emotion catego...
Examining the Role of Eye Movements During Conversational Listening in Noise.

Speech comprehension is often thought of as entirely auditory, but both normal hearing and hearing-impaired individuals sometimes use visual attention to disambiguate speech, particularly when it is difficult to hear (Rosenblum, Johnson, & Saldana, 1996; Sumby & Pollack, 1954). Many studies have investigated how visual attention (or the lack thereof) impacts the perception of simple speech sounds such as isolated consonants, but there is a gap in the literature concerning visual attention during natural speech comprehension. This issue needs to be addressed, as individuals process sounds and words in everyday speech differently than when they are separated into individual elements with no competing sound sources or noise. Moreover, further research is needed to explore patterns of eye movements during speech comprehension – especially in the presence of noise – as such an investigation would allow us to better understand how people strategically use visual information while processing speech. To this end, we conducted an experiment to track eye-gaze behavior during a series of listening tasks as a function of the number of speakers, background noise intensity, and the presence or absence of simulated hearing impairment. Our specific aims were to discover how individuals might adapt their oculomotor behavior to compensate for the difficulty of the listening scenario, such as when listening in noisy environments or experiencing simulated hearing loss. Speech comprehension difficulty was manipulated by simulating hearing loss and varying background noise intensity. Results showed that eye movements were affected by the number of speakers, simulated hearing impairment, and the presence of noise. Further, findings showed that differing levels of signal-to-noise ratio (SNR) led to changes in eye-gaze behavior. Most notably, we found that the addition of visual information (i.e., videos vs auditory information only) led to enhanced speech comprehension – highlighting the strategic usage of visual information during this process.
Surface plasmon resonance, Orbitrap mass spectrometry and Raman advancements: exciting new techniques in drug discovery

A significant number of diverse and multidisciplinary research areas ranging from protein chemistry, enzyme kinetics to drug discovery require elucidation of macromolecular interactions such as pro...
In Situ Observation of Reaction Fronts During the Initial Stages of Iron Surface Oxidation at 1150 °C

This study focuses on the initial stages of iron surface oxidation, studied by confocal scanning laser microscopy. Pure iron cubes were prepared and polished for in situ observation. Samples were oxidized for 2–60 s by dry air at 1150 °C. A dynamic oxidation process was observed, with two reaction fronts that moved from the sample edge to the center at around 20–30- and around 40–50-s oxidation, respectively. Scanning electron microscopy (SEM) was used to characterize the iron oxide surface morphology. Pyramidal features appeared first on the surface, and then the surface became flatter with time. X-ray diffraction was used to characterize the phases of the outermost oxide layer. Overall, the content of wustite decreased and hematite content increased with oxidation time. SEM with a backscattered electron detector was used to measure the oxide layer thicknesses, and it was found that the oxide thickness increased parabolically with time. The different oxide layers within the scale were identified by an optical microscope with a polarized light source. Even after 2-s oxidation, an obvious magnetite layer was found on the wustite layer, and after 10-s oxidation, an obvious hematite layer was observed on the magnetite layer. A thicker hematite layer was observed at the sample edge. The reasons for the morphology changes are discussed.
Inundation time mediates denitrification end products and carbon limitation in constructed floodplains of an agricultural stream

Conversion of landscapes to large-scale agriculture has substantially increased the loading of bioavailable nitrogen (N) to stream networks through extensive artificial drainage and fertilizer application. Floodplain restoration may enhance N cycling in agricultural stream systems by increasing residence time of floodwaters in contact with bioreactive surfaces that retain or remove excess N. Microbially-mediated denitrification potentially plays a significant role in constructed floodplains by permanently removing excess N through conversion of bioavailable nitrate (NO3-N) to dinitrogen gas, either as N2O or N2. Restoring channelized streams via the construction of inset floodplains can increase the total denitrification capacity of agricultural watersheds, but little is known about the abiotic factors that control the proportion of NO3-N that is converted to the potent greenhouse gas N2O versus N2 (i.e., N2O yield). We used an in-situ static core design to assess the importance of constructed floodplain age, inundation time, and carbon (C) availability on total denitrification rates and N2O yield. Novel use of membrane-inlet mass spectrometry (MIMS) allowed us to simultaneously measure N2O and N2 to capture total denitrification and the proportion of bioavailable N converted to each end-product. Floodplain age did not influence total denitrification rates, but rather denitrification increased with the duration of floodplain inundation until C limitation occurred at approximately 24 h. In addition, we found that N2O yields from floodplain soils were higher than those reported for other aquatic systems. Finally, while floodplain restoration in agricultural streams generally increases N retention at the watershed scale, regardless of the restoration age, the impact of added floodplains on N2O emissions should be considered.
Kidney transplant in the COVID era: Cautious optimism and continued vigilance.

Since early March, transplant centers throughout the country have attempted to balance the risk of COVID-19 transmission in a newly immunosuppressed transplant recipient with the concern for wait list mortality and life years lost by remaining on dialysis. Much of the deliberation over this balance has occurred through online discussion groups where the sentiments are aligned, but the community risk, center resources, and population demographics are vastly different. Dr. Massie and coauthors provide data driven support for decision making by modeling the benefit to harm ratio of kidney transplant under varying environmental conditions, and providing a user-friendly calculator at transplantmodels.com/covid_sim.1.
Residual Stress Generation in Laser-Assisted Cold Spray Deposition of Oxide Dispersion Strengthened Fe 91 Ni 8 Zr 1

This paper examines the residual stresses generated by laser-assisted cold spray deposition of an iron-based oxide dispersion strengthened alloy (Fe91Ni8Zr1 at.%) on an AISI 1018 mild steel substrate, as well as studies of the effect of the laser heating on the substrate alone. The in-plane residual stress values were determined by X-ray diffraction-based measurements. In the top section of the layers, established at a raster deposition rate of 25 mm/s and simultaneous surface heating temperatures of 650 and 950 °C, stresses were compressive ranging from − 170 to − 440 MPa. For the substrate only study, a larger span of surface temperatures from 350 to 950 °C and scan rates of 5 and 25 mm/s were investigated. Here, the stresses in the laser tracks were tensile, of the order of + 400 MPa, with both “W''- and “M”- shaped profiles about the laser centerline. It was found that the stress profile shape was influenced by the Gaussian power distribution across the laser spot diameter which correlated with microstructural changes (martensite formation) in the substrate.
Resisting redevelopment: protest in aspiring global cities

The demolition of old neighbourhoods and displacement of indigenous residents are not new in modern cities. From Baron Haussmann’s transformative redesign of Paris in the nineteenth century to the ...
The Savage Effects of Racism in Schools and Society Exposed

The word savage comes to the forefront of controversial debates revolved around slavery and colonization. This word is racially loaded, and has been horrifically used to misrepresent and stigmatize people of color, particularly Blacks and Native Americans. Specifically, because the savage label has been attached to the racial and cultural identities of historically oppressed groups, they have suffered a great deal of oppression, including “symbolic violence” (Bourdieu, 1991, 1998). For example, Native American school children were stigmatized as savage, removed from their families, and placed in White Christian schools to be civilized supposedly (Spring, 2010). For the purpose of this book, the word savage is specifically used to expose brutal forms of systemic racism that have been inflicted on the soul, spirit, and body of Black and Brown people, including school children of color. The historical construction of the word savage and its negative connotations associated with people of color are explored in this chapter in order to demonstrate the manner in which it is connected to the legacy of slavery, colonization, and white supremacy, and how it continues to be used to stereotype, stigmatize, and discriminate against people of color, particularly Naive Americans and Blacks.
Disentangling individual, school, and neighborhood effects on screen time among adolescents and young adults in the United States.

Abstract Objectives To examine the association between individual, neighborhood, and school-level influences on individual screen time among adolescents and young adults (AYAs) in the National Longitudinal Study of Adolescent to Adult Health. Methods We classified screen time continuously as self-reported total hours per week of television, videos, and video/computer games at baseline and categorical as extended screen time (≥14 h per week). We fit cross-classified multilevel models (CCMM) to examine to examine the individual-, school- and neighborhood-level demographic and socioeconomic factors associated with screen time. Models were fit using MLwiN with Bayesian estimation procedures. Results AYAs reported an average of 22.8 (SD = 19.4) and 21.9 (SD = 20.3) hours of screen time, respectively. At the individual level, younger age, male sex, Black/multiracial race, receipt of public assistance, and lower parental education were associated with higher screen time. At the school level, being out of session (i.e., school and national holidays including summer), having a higher proportion of non-White students, and having a lower proportion of parents with a college education were associated with higher individual screen time. Conclusions We found that individual-level factors most influence youth screen time, with smaller contributions from school factors.
Quantitative Correlation between the Degree of Reaction and Compressive Strength of Metakaolin-Based Geopolymers

For geopolymers (usually composed of unreacted precursor and gel), the compressive strength is controlled by two factors. The first is the degree of reaction, or, equivalently, the amount of gel formed, including any calcium silicate hydrate gel in calcium-containing mixtures. The second factor is the gel composition, generally given by the Si/Al ratio. These two parameters are interrelated for typical silicate-activated metakaolin geopolymers. By separating out effects of Si/Al ratio and degree of reaction, this study quantitatively correlates the degree of reaction with the compressive strength of metakaolin-based geopolymers with and without calcium. Solid-state 29Si nuclear magnetic resonance (NMR) aided with chemical extractions was used to determine gel amounts and composition for several geopolymer mixtures. The compressive strength was also measured for each mixture at 7 days. Both the increase of Na/Al ratio in mixtures without calcium and addition of external calcium increased the degree of reaction, and compressive strength correlated linearly (R2 > 0.88) with the degree of reaction.
Minimally invasive treatment of laryngoceles: a systematic review and pooled analysis

Laryngoceles are best treated with surgery. The goal of this study is to compare patient outcomes and complications in patients undergoing removal of laryngoceles with either transoral endoscopic/microlaryngoscopic or robotic approaches. A systematic review of the published literature was conducted using Pubmed, Web of Science, and the Cochrane Clinical Trials databases. A pooled analysis of individual data was used to compare outcomes between robotic and endoscopic approaches. A total of 30 studies were included. Nine studies with 95 patients were included in the final analysis. Eighty-one (85.26%) were treated with microlaryngoscopic surgery and 14 (14.74%) were treated with robotic-assisted surgery. The rates of tracheostomy (RR = 1.44, 95% CI = 0.389–5.332), complications (RR = 0.329, 95% CI = 0.047–2.294) and recurrence (RR = 0.354, 95% CI = 0.021–5.897) were not statistically different between groups. Within the endoscopic subgroup, 66 laryngoceles (78.57%) were completely excised, while 18 (21.43%) laryngoceles were treated with marsupialization. Marsupialization was associated with an increased risk of recurrence (RR = 4.889, 95% CI = 1.202–19.891). In the robotic subgroup, there was an increased risk of nasogastric tube use (RR = 103.867, 95% CI = 6.379–1619.214) and a longer mean length of hospital stay (p = 0.0001). Transoral treatment of laryngoceles has complication and recurrence rates of 18.95% and 7.37%, respectively. Robotic approaches are associated with higher rates of NGT use and increased hospital stay, however much of this is due to one robotic surgeon’s preference for routine NGT placement and higher rates of combined laryngocele removal via robotic approach. Complete excision of combined laryngoceles is possible with transoral approaches. Marsupialization, reported in traditional endoscopic approaches, is associated with a significantly higher rate of recurrence (22.22% vs. 4.76%).
Working with the Ancestors: Mana and Place in the Marquesas Islands

Emily C. Donaldson explores the concept of global heritage management in the context of indigenous Marquesan perspectives. In doing so, it highlights several problems inherent in the dominant herit...
Radiation Characterization of Leaky Guided Waves in Monolithic and Sutured Cranial Bones

Leaky guided (Lamb) waves show promise to access the brain periphery efficiently as an alternative to conventional transcranial ultrasound with bulk waves. However, their radiation characteristics are affected by the complex geometry and porosity of cranial bones. Furthermore, the effects of sutures are not well understood. Here, the radiation angle dispersion spectra of guided waves are studied experimentally via submersed pressure scans and compared with numerical results. The prominent radiation angles are associated to guided wave modes with high out-of-plane polarization and low attenuation. Additionally, the radiation characteristics for bone segments with sutures are contrasted with those obtained for monolithic bone.
Application of Interweaving in DLMs to an Exchange and Specialization Experiment

Markov chain Monte Carlo is often particularly challenging in dynamic models. In state space models, the data augmentation algorithm (Tanner and Hung Wong, J. Am. Stat. Assoc. 82(398):528–540, 1987) is a commonly used approach, e.g. (Carter and Kohn, Biometrika 81(3):541–553, 1994) and (Fruhwirth-Schnatter, J. Time Ser. Anal. 15(2):183–202, 1994) in dynamic linear models. Using two data augmentations, Yu and Meng (J. Comput. Graph. Stat. 20(3): 531–570, 2011) introduces a method of “interweaving” between the two augmentations in order to construct an improved algorithm. Picking up on this, Simpson et al. (Interweaving Markov chain Monte Carlo strategies for efficient estimation of dynamic linear models, Working Paper, 2014) introduces several new augmentations for the dynamic linear model and builds interweaving algorithms based on these augmentations. In the context of a multivariate model using data from an economic experiment intended to study the disequilibrium dynamics of economic efficiency under a variety of conditions, we use these interweaving ideas and show how to implement them simply despite complications that arise because the model has latent states with a higher dimension than the data.
A new slant on the development of orientation selectivity.

High-resolution analysis of immature receptive fields in lateral geniculate neurons suggests that transient oriented receptive fields in the thalamus may contribute to the development of orientation selectivity in visual cortex.
Inductive Inference, DFAs, and Computational Complexity

This paper surveys recent results concerning the inference of deterministic finite automata (DFAs). The results discussed determine the extent to which DFAs can be feasibly inferred, and highlight a number of interesting approaches in computational learning theory.
On Being Anti-Cartesian: Hegel, Heidegger, Subjectivity, and Sociality

I. Being-in-the-world and Not-Being-in-the-world Contrary to Heidegger's own view, both Hegel and Heidegger are, I shall claim, anti-Cartesians. (According to Heidegger, Hegel was the greatest Cartesian.) I shall not be concerned here with the historical Descartes, the comments of either about Descartes, Heidegger's peculiar reading of Hegel, or anything like a full exposition of each position. Rather I am interested in the theoretical implications both draw from being anti- Cartesian, where that notion is understood in the following limited way. Hegel and Heidegger understand Cartesian philosophy traditionally, as arguing that the possibility of any cognitive or even intelligible relation to the world resides in mental episodes occurring in individual minds. The world and entities within the world are, originally, significant or meaningful only as a result of the occurrence of such subjective states, or of some subject's intending, or linguistic, or representing, or synthesizing activities. (Both, in other words, would regard naturalistic, neuroscientific, and psyichologistic accounts of such cognitive relations as still Cartesian, even if not wedded to the metaphysics of immaterialism. The key issue is whether representative success, or intelligibility in our dealings with the world, is something achieved by an individual subject's activity or processing, is a result . Although it might sound curious to put it this way, Mentalism, or some claim that significance is conferred by individual minds, is still mentalism, no matter what mens is said to be made of or how it works.)
Near‐Miss Management: A Participative Approach to Improving System Reliability

Investigations of many serious accidents in different fields have revealed that before every serious accident, a large number of related prior incidents occurred with limited impact and an even larger number of related incidents happened that resulted in no loss or damage. Collectively, these incidents are called near-misses. Near-misses provide insight into both potential failure points and weaknesses in the management system itself. Therefore, they can be a powerful tool to reduce risk and improve system reliability. Near-miss management systems (NMMS)s are designed to enable people and institutions to learn from high-frequency, low-impact incidents (near-misses) to prevent low-frequency, high-impact events (accidents). A comprehensive NMMS includes several important implementation steps, such as identification of near-misses, disclosure and reporting, prioritization and classification, distribution of the information, analysis of causes, solution identification, dissemination of actions and knowledge, resolution, and closure of the case. Successful implementation of an NMMS requires (a) strong management ownership, (b) participation and reporting of as many incidents as possible, and (c) use of quantitative tools to identify weaknesses and to improve the system. Keywords: near-miss; accident; safety; management; risk; reliability
Flexible Packaging for Thermoprocessed Foods

Publisher Summary This chapter covers the use of flexible packaging for thermoprocessed foods in depth, considering all efforts up to 1960 as historical, and all subsequent developments according to specific technical areas. An attempt has been made to cover the basic early work on feasibility of the method and definition of problems. Generally, the developments after 1961 have been refinements, assurances of capabilities, and transitions to commercial production. It discusses about the materials in detail. It delves into the general aspects, extractives, bacterial penetration, retortability, and current films. The subsequent section discusses package designs and food product development. It also presents a discussion on the production systems. It explains about the sealing in detail. The effect of retorting and storage on heat seals, the significance of interlamina bonds in the seal area, the effects of occluded particles in closure seals, and the methods for sealing retort pouches are discussed. The next section discusses about filling systems in detail. The general aspects of air removal, specific techniques, and methods of determining residual gas levels are explained. The chapter covers a discussion on retorting and package durability. The general aspects of quality assurance, system specifications and sampling protocol, and specific tests are explained. The future research, and development needs are discussed in the last section.
An improved algorithm for algebraic curve and surface fitting

The author describes a new method to improve the algebraic surface fitting process by better approximating the Euclidean distance from a point to the surface. In the past they have used a simple first order approximation of the Euclidean distance from a point to an implicit curve or surface which yielded good results in the case of unconstrained algebraic curves or surfaces, and reasonable results in the case of bounded algebraic curves and surfaces. However, experiments with the exact Euclidean distance have shown the limitations of this simple approximation. Here, a more complex, and better, approximation to the Euclidean distance is introduced from a point to an alegbraic curve or surface. It is shown that this new approximate distance produces results of the same quality as those based on the exact Euclidean distance, and much better than those obtained using other available methods. >
Criteria for Passing Sight Distance for Roadway Design and Marking

The need for changes in the criteria for passing sight distance (PSD) used for design of two-lane highways and for marking of passing and no-passing zones on two-lane highways was investigated. PSD models from the AASHTO Green Book and the Manual on Uniform Traffic Control Devices were first compared with models developed in previous research to determine the most accurate representation of the passing maneuver. Two existing models warranted further consideration. Field studies were then conducted in Missouri and Pennsylvania; recent field data from a study in Texas were also evaluated to validate the assumptions made in the passing models. On the basis of current driver behaviors, no change was needed in the PSD criteria used for marking passing and nopassing zones. The research found that two-lane highways could be safely designed with PSD criteria equal to or greater than the PSD criteria used in marking passing and no-passing zones, instead of the longer PSD values currently used in design. Therefore,...
CCD polarization imaging sensor with aluminum nanowire optical filters

We report an imaging sensor capable of recording the optical properties of partially polarized light by monolithically integrating aluminum nanowire optical filters with a CCD imaging array. The imaging sensor, composed of 1000 by 1000 imaging elements with 7.4 μm pixel pitch, is covered with an array of pixel-pitch matched nanowire optical filters with four different orientations offset by 45°. The polarization imaging sensor has a signal-to-noise ratio of 45 dB and captures intensity, angle and degree of linear polarization in the visible spectrum at 40 frames per second with 300 mW of power consumption.
Distribution of intraprostatic hyperechoic lesions in infertile men

Abstract Objectives To determine whether intraprostatic hyperechogenic lesions seen on transrectal ultrasonography are related to infertility. Methods The transrectal ultrasonographic studies of 58 infertile men and 12 fertile controls who all had intraprostatic hyperechoic lesions were reviewed to determine the anatomic distribution of hyperechoic lesions within the prostate and their relationship to the ejaculatory ducts. Results Hyperechoic lesions were located in the region of the verumontanum in 62% of the fertile control subjects and only 22% of infertile patients (P Conclusions Hyperechogenic lesions located within the verumontanum appear to be a normal finding in fertile men, whereas lesions located in the region of the ejaculatory ducts are more likely to be associated with infertility.
Endoscopy in acute upper gastrointestinal bleeding.

1. The findings in early endoscopy in a series of patients with acute upper gastrointestinal bleeding of undetermined source are presented.
Genetics and molecular biology of the inherited long QT syndrome.

Two forms of the inherited long QT syndrome have been known for many years: the autosomal recessive Jervell and Lange-Nielsen form and the autosomal dominant Romano-Ward form. A gene marker at the 11p 15.5 locus has been identified for some, but not all, families with the autosomal dominant form, but as yet the gene has not been identified. It is apparent that mutations of at least four genes, and possibly more, can cause the syndrome.The molecular biology of the syndrome is not yet clarified, but abnormalities of ion channel function are likely, particularly the potassium delayed rectifier current. Proposals for the pathophysiology include an abnormality of a G protein which controls ion channel and adrenergic pathway function, as well as a disturbance of the sympathetic nervous system. The identification of the abnormal gene(s) and the gene products will provide precise information on the molecular physiology of the syndrome.
Laboratory notes: Homemade aids for metallographic sample preparation

Abstract Three home‐made laboratory aids for metallographic and cross‐sectional studies are described. These include an innovative specimen holder for mounting small samples at any desired angle, a specimen dryer which has greater utility than commercially available units, and a small specimen leveling press. A short account of the need for sample removal and techniques of mounting samples are discussed.
Dynamic Failure Control for Military Electronics

Failures in electronic equipment can cost time, effort, supplies, money and even lives. Most reliability programs concentrate almost exclusively upon failure prevention; their main interest seems to be in developing failure resistant components and equipment. However, to assume that such an approach can eliminate all possibility of failure is unrealistic. It is much more practical to view the tendency to failure as ever-present and to place more emphasis upon control of failures and their effects (a concept including but not limited to prevention). There is, a close analogy between the nondnamic approach to reliability and the ``Maginot Line'' type of military strategy, and between the dynamic failure control approach advocated here and the modern ``Atomic War'' type of strategy. The notorious ``game'' of Russian Roulette is used as an example, purposely far removed from electronics, of the dynamic approach to failure control and of the importance to dynamic failure control of thorough systems analysis.
Quantifying the health benefits of genetic tests: a clinical perspective.

This editorial discusses reports that analyzed and developed models for assessing the impact of genetic tests on health outcomes and health care delivery.
Polymorphonuclear leukocyte dysfunction in children with recurrent otitis media

Peripheral polymorphonuclear leukocyte function was studied in 102 children, age 6 months through 12 years, with persistent middle-ear effusion and recurrent acute otitis media. All of the patients were initially studied when ventilation tubes were inserted. Serous effusion was found in 19% of middle ears and mucoid effusion in 54%. Hemophilus influenzae and Staphylococcus epidermidis were the most common organisms in culture positive effusions. Depressed PMN chemotactic responsiveness was observed in 17.5% of 97 patients studied, depressed PMN bactericidal activity in 23.3% of 30 patients, and depressed PMN chemiluminescence activity in 15.8% of 19 patients. Depressed chemotactic responsiveness was found more often in patients less than 3 years of age who had their initial bout of acute otitis media prior to age one year. These children also most frequently cultured H. influenzae from their effusions. Of 30 patients whose PMNs were studied for both chemotactic and bactericidal responsiveness, four (13.3%) had a combined defect, three (10%) had only depressed bactericidal activity, and two (6.7%) had only depressed chemotaxis. Repeat PMN function studies were performed after surgery in six children and were normal in four, suggesting that leukocyte dysfunction was transient, and possibly associated with the presence of middle-ear effusion.
The influence of maternal age and mating frequency on egg size and offspring performance in Callosobruchus maculatus (Coleoptera: Bruchidae)

Maternal age influences offspring quality of many species of insects. This observed maternal age influence on offspring performance may be mediated through maternal age effects on egg size, which in turn may be directly influenced by the female's nutritional state. Thus, behaviors that influence a female's nutritional status will indirectly influence egg size, and possibly offspring life histories. Because males provide nutrients to females in their ejaculate, female mating frequency is one behavior which may influence her nutritional status, and thus the size of her eggs and the performance of her offspring. In this paper, I first quantify the influences of maternal age on egg size and offspring performance of the bruchid beetle, Callosobruchus maculatus. I then examine whether nutrients transferred during copulation reduce the magnitude of maternal age effects on egg size and larval performance when mothers are nutrient-stressed. Egg size and egg hatchability decreased, and development time increased, with increasing maternal age. Multiple mating and adult feeding by females both resulted in increased egg size. This increase in egg size of females mated multiply did not translate into reduced development time or increased body size and egg hatchability, but did correlate with improved survivorship of offspring produced by old mothers. Thus, it appears that because the influence of mating frequency on egg size is small relative to the influence of maternal age, the influence of nutrients derived from multiple mating on offspring life history is almost undetectable (detected only as a small influence on survivorship). For C. maculatus, female multiple mating has been demonstrated to increase adult female survivorship (Fox 1993a), egg production (Credland and Wright 1989; Fox 1993a), egg size, and larval survivorship, but, contrary to the suggestion of Wasserman and Asami (1985), multiple mating had no detectable influence on offspring development time or body size.
THE STANDARDIZATION OF PUBLIC HEALTH WORK.

STANDARDIZATION APPLIED TO PUBLIC HEALTH WORK. It has for its end the establishment of means by which the publicmay ascertain the relative efficiency of health officers. For behold, there are good and bad health officers, just as there are good and bad men, good and bad doctors, good and bad angels. The people who employ the health officersboth kinds-should have some way of differentiating between the genuine and counterfeit. A standard should be created, if such is possible. Those who have the political right to select and dismiss health officials should also be given an intelligent right so to do. I believe public health work can be standardized.
Silicone Implant Arthroplasty in Patients With Idiopathic Osteoarthritis of the Metacarpophalangeal Joint

Purpose The outcome of silicone metacarpophalangeal (MCP) joint implant arthroplasty in the osteoarthritic patient population has not been well established. Typically patients with idiopathic osteoarthritis have no history of underlying systemic disease and may respond well to treatment with MCP joint implant arthroplasty. This study examined the efficacy of silicone MCP joint implant arthroplasty for patients with idiopathic osteoarthritis for whom nonsurgical treatment had failed. Methods Of 14 patients (15 arthroplasties) who had silicone MCP joint implant arthroplasty for idiopathic osteoarthritis 12 (13 arthroplasties) returned for follow-up evaluation at an average of 40 months after surgery. There were 9 index finger and 4 middle finger arthroplasties. The average age at the time of surgery was 62 years. Patients completed a subjective questionnaire and were examined by a certified therapist. Range of motion and strength were recorded and the Jebsen-Taylor examination was administered to assess function. Range of motion values at final follow-up evaluation were compared with preoperative and early postoperative values. Radiographs were taken at final follow-up evaluation and compared with preoperative and early postoperative films to assess joint position, wear, and radioulnar alignment. Results At final follow-up evaluation excellent (9 patients) and good (3 patients) overall improvement were reported. Nine patients (10 implants) reported greater than 75% functional improvement. A notable increase was seen in MCP joint flexion. Grip and lateral pinch strengths were below age-matched normative data. Of the 11 patients (12 implants) who came in for follow-up evaluation 7 performed all tasks of the Jebsen-Taylor examination within the allotted time. At final follow-up evaluation all silicone implants were located and showed no signs of subluxation. Radiographic radioulnar alignment was maintained. One implant was revised at 35 months secondary to fracture. Conclusions Silicone implant arthroplasty is a motion-sparing procedure that provides good pain relief and maintenance of function at intermediate follow-up evaluation in patients with idiopathic osteoarthritis of the MCP joint.
The Practical Application of Surface Electrical Resistivity to Detection of Ground-Water Pollution

One of the primary problems in field investigations of ground-water pollution is locating the contaminant plume. Drilling of sampling holes on a hit-or-miss basis is both time-consuming and expensive. Under many subsurface conditions, surface electrical resistivity profiling can quickly and cheaply locate the general position of the plume and identify areas most feasible for sampling and monitoring. Many contaminants contain an ionic concentration considerably higher than the background level of native ground water. When such a contaminant is introduced into an aquifer, the electrical resistivity of the saturated soil is reduced. Surface electrical resistivity profiling across a suspected area can identify this reduced resistivity zone as an anomaly. The sensitivity of the method depends on relative uniformity of geology and topography as well as minimal extraneous electrical interferences. It is also essential that the “A” spacing used in the profiling procedure be carefully selected. If the resistivity contrast between contaminated and uncontaminated ground water is high, detection of at least the central part of the plume is likely within expected geologic variation. The method has been successfully used in the location of plumes from contaminants including brine, uranium reprocessing liquid wastes and landfill leachate in glacial deposits of New England.
Databases and political science research

To date, librarians have not produced a study comparing databases that are appropriate for political science research. This study compares the coverage, content, and retrieval methods for nine databases. The study uses sampling to evaluate search results for six topics, providing relevancy percentages for each database. The article also reviews the types of documents cited in these samples, and provides recommendations for matching each database to particular research needs.
Evaluation of pretest and exercise test scores to assess all-cause mortality in unselected patients presenting for exercise testing with symptoms of suspected coronary artery disease.

Abstract Objectives To determine how well recently developed multivariables scores assess for all-cause mortality in patients with suspected coronary disease presenting for exercise electrocardiography (ExECG). Background Recently revised American College of Cardiology/American Heart Association guidelines for ExECG have suggested that ExECG scores be used to assist in management decisions in patients with suspected coronary artery disease. Recently developed scores accurately stratify patients according to angiographic disease severity. Methods To determine how well these scores assess for all-cause mortality, we utilized 4,640 patients without known coronary disease who underwent ExECG to evaluate symptoms of suspected coronary disease between 1995 and 2001. Previously validated pretest and exercise test scores as well as the Duke treadmill score were applied to each patient. All-cause mortality was our end point. Results Overall mortality was 3.0% with 2.8 ± 1.6 years of follow-up. All three scores stratified patients into low-, intermediate-, and high-risk groups (p Conclusions Simple pretest and exercise scores risk-stratified patients with suspected coronary disease in accordance with published guidelines and better than the Duke treadmill score. These results extend to diabetics, inpatients, women, and patients on beta-blockers.
The role of elastic interaction stresses on the onset of slip in polycrystalline alpha brass—II. Rationalization of slip behavior

Abstract A finite element method analysis, extended to three dimensions, was used to calculate the stresses in 11 grains of an as-cast, 2.4 mm grain size α-brass specimen strained to the proportional limit. Resolved shear stresses (RSS) were not uniformly distributed. However, the predicted slip system based on highest total RSS was found to operate in 9 of the 11 grains. In the other two cases it was not possible to predict which of the two highest RSS slip systems would operate because the RSS were too close. RSS at which slip occurred were compatible with those found by other investigators and measured slip offsets were generally higher where the calculated stresses were higher. Second highest or lower RSS slip systems, which did not form strong obstacles with the primary slip systems, were found to operate. The range of stresses in a given grain, over which slip occurred increased with grain size. On the basis of available evidence, it must be considered that elastic interaction stresses play an important role in the yield process and may exercise influence for strains of at least several percent.
Clinical and pharmaceutical applications of packed‐column supercritical fluid chromatography

Packed-column supercritical fluid chromatography (pSFC) is a fast separation technique that combines the properties of HPLC and GC. pSFC with carbon dioxide as the mobile phase and packed silica column as the stationary phase possesses the properties of normal phase mechanism; however, the addition of modifiers to the mobile phase allows the separation of relatively polar compounds. In spite of its many positive attributes, pSFC has not been widely used in areas such as proteomics, where methods such as HPLC dominate. Packed column SFC has been extensively used in clinical and pharmaceutical laboratories, especially for separation of nonpolar and chiral drugs. This review will discuss recently published applications of pSFC, with a specific focus on its advantages and limitations for the analysis of pharmaceuticals with varying chemical properties.