cssi/SciSciGPT-SciSciNet huggingface dataset:
Factors Associated With Cancer Disparities Among Low-, Medium-, and High-Income US Counties

Background There are concerns about the degree to which county income level might underlie the stark disparities in cancer death rates among US counties; at the same time, there is uncertainty about the factors that may mediate the disparities. Objectives To assess county-level cancer death rates and to identify possible mediators of the association between county-level median incomes and cancer death rates. Design, Setting, and Participants Cross-sectional study using death records from the National Center for Health Statistics in 2014, with data collected and analyzed between October 1, 2016, and July 31, 2017. All US counties and county equivalents were included. Exposures County-level median household income. Main Outcomes and Measures County-level age-standardized cancer death rate. Results In 3135 counties, median incomes ranged from $22 126 to $121 250 per year. Low-income counties (median income, $33 445) vs high-income counties (median income, $55 780) had higher proportions of residents who were non-Hispanic black, lived in rural areas, or reported poor or fair health. The mean (SD) cancer death rate was 185.9 (24.4) per 100 000 person-years in high-income counties, compared with 204.9 (26.3) and 229.7 (32.9) per 100 000 person-years in medium- and low-income counties, respectively. In mediation models, health risk behaviors (smoking, obesity, and physical inactivity); clinical care factors (unaffordable care and low-quality care); health environments (food insecurity); and health policies (state smoke-free laws and Medicaid payment rates) in aggregate accounted for more than 80% of the income-related disparity. The strongest possible mediators were food insecurity (explaining 19.1% [95% CI, 12.5%-26.5%] of the association between county incomes and cancer deaths), low-quality care (17.9%; 95% CI, 14.0%-21.8%), smoking (12.7%; 95% CI, 9.4%-15.6%), and physical inactivity (12.2%; 95% CI, 9.4%-15.6%). Conclusions and Relevance There are wide gaps in cancer death rates between low-, medium-, and high-income counties. Future studies are needed to assess whether targeting the possible mediators might ameliorate the substantial socioeconomic cancer disparities.
Host-parasite interactions: an interview with Emily Troemel.

Emily Troemel is a Professor at the University of California San Diego, where her lab uses Caenorhabditis elegans to study host–pathogen interactions and the shaping of the immune response. In this interview, Emily shared her thoughts on peer review and its role in training future scientists, and the possibility of a new form of immunity in epithelia.
Safety and efficacy of over-the-scope clip-assisted full thickness resection of duodenal subepithelial tumors: A case report

Safety and efficacy of over-the-scope clip-assisted full thickness resection of duodenal subepithelial tumors: A case report
Familial Capital, Narratives of Agency, and the College Transition Process for Refugee-Background Youth

AbstractThis study examines the role of family in the college transition process for students with refugee backgrounds in New England (United States). Extant research finds that the investments imm...
The SCALE/AMPX multigroup cross section processing for fast reactor analysis

Abstract The SCALE/AMPX multigroup (MG) cross section processing procedure has been updated to minimize reactivity differences for fast reactor designs and boiling water reactors (BWRs) with very high void fractions to provide excellent agreement with continuous-energy reference calculations. SCALE MG calculations are widely applied to thermal spectrum light-water reactor (LWR) systems as well as fast spectrum metallic systems of interest to National Nuclear Security Administration. With growing interest from industry and regulators in applying SCALE for the design of fast spectrum reactors, both sodium and molten salt, and in the licensing of power up rates for BWRs, it is desirable to review the SCALE/AMPX procedure for unresolved resonance self-shielded data and high energy neutron spectra. The data were improved by generating MG unresolved resonance data based on the analytic probability table method with the narrow resonance approximation as well as the use of a very fine group structure typically used in fast system analysis. This study focused on verifying the probability table and the SCALE/AMPX MG cross section processing procedure by performing reaction rate analysis and benchmark calculations for various fast reactor and high void BWR systems. Results indicate that the improved SCALE/AMPX MG cross section processing provides excellent results for the fast reactor analysis.
The economic impacts of blackbird (Icteridae) damage to sunflower in the USA.

Background Blackbird (Icteridae) damage to ripening sunflower (Helianthus annuus L.) has been a persistent economic issue in the USA for the last five decades. To quantify losses, we surveyed blackbird damage from 2001 to 2013 (excluding 2004) to physiologically mature sunflower in eight states: North Dakota, South Dakota, Texas, Nebraska, Minnesota, Colorado, Kansas, and Vermont. Results We pooled data gathered during the most recent 5 years (2009 to 2013) of the survey and found losses averaged $US2.5 million and $US11.3 million for confectionery and oilseed hybrids, respectively. Three states, North Dakota, South Dakota, and Nebraska, had sufficient acreage and bird damage to warrant economic analyses using a regional economic model. The average annual total (direct plus indirect) economic impact of bird damage to sunflower production for North Dakota, South Dakota, and Nebraska was $US18.7 million, $US7.3 million, and $US2.6 million, respectively. Conclusion This study provides a better understanding of the broader economic implications of bird damage to sunflower by estimating the macroeconomic impacts of lost sunflower production in the region. Additionally, the findings of this study may be used to inform decisions regarding bird management policy by providing policymakers with information to determine the downstream value of bird management and the possible benefits of improved methods that further mitigate losses. © 2019 Society of Chemical Industry.
Stream and floodplain restoration impacts riparian zone hydrology of agricultural streams.

While the influence of stream restoration on vertical and lateral hyporheic exchange has been documented, impacts on broader riparian zone hydrology have not been thoroughly investigated. We quantified riparian water table dynamics, hydraulic gradient, and groundwater flow paths and fluxes across a range of hydrologic conditions following natural channel design restoration (riparian regrading, in-channel cross-vane structure installation). Water table measurements were collected at least once per season for 2.5 years to capture water levels during baseflow conditions from networks of wells and piezometers at sites with different stream morphology (created riffle-cross-vane-scour pool complexes versus natural pools and riffles), restoration status (agricultural restored, unrestored, forested reference), and riparian characteristics (slope, soils, topography) in North Carolina, USA. The regraded riparian zone had higher near-stream water tables (< 0.5 m below ground surface) than the unrestored site. Riffle-cross-vane complexes induced a zone of low hydraulic gradient that spanned 30–40% of the riparian area, similar to groundwater dynamics near beaver dams. This effect persisted regardless of hydrologic condition (wet or dry) or scour pool status (functioning or filled-in). Riffles also promoted a lower near-stream hydraulic gradient at the forested site. Conversely, the influence of stream features on riparian groundwater was minimal at the unrestored site, where groundwater fluxes were controlled by hillslope inputs and riparian geomorphology. Overall, restoration enhanced stream-riparian zone hydrologic interaction beyond the immediate hyporheic zone. Our work stresses that cross-vanes, even when partially buried by sediments post-restoration, impact whole floodplain hydrology in a more significant way than shown by prior stream restoration studies.
Distribution of High-Volume Ankle Replacement Surgeons in United States Metropolitan Areas.

BackgroundAnkle osteoarthritis is increasing, thus creating greater demand for high-volume total ankle arthroplasty (TAA) surgeons. The Medicare Provider Utilization and Payment Data Public Use Fil...
Military Integrated Circuits Screening Report (Summary) ESSEH Parts Committee

Electronic parts suppliers, original equipment manufacturers (OEMs), and government agencies have reported divergent perceptions of military integrated circuit quality. In 1986 the Environmental Stress Screening of Electronic Hardware (ESSEH) Parts Committee was formed. This committee accepted the task of identifying the underlying problems related to these perceptions. This report presents the strategy and a pilot implementation, as well as development of a standard for exchange of quality data. It includes specific rescreening data and analysis of correlation issues.The report shows that most components are defect free, and that supplier/OEM teams can systematically resolve correlation and quality issues.
Emergence of nosocomial associated opportunistic pathogens in the gut microbiome after antibiotic treatment.

According to the Centers for Disease Control’s 2015 Hospital Acquired Infection Hospital Prevalence Survey, 1 in 31 hospital patients was infected with at least one nosocomial pathogen while being treated for unrelated issues. Many studies associate antibiotic administration with nosocomial infection occurrence. However, to our knowledge, there is little to no direct evidence of antibiotic administration selecting for nosocomial opportunistic pathogens. This study aims to confirm gut microbiota shifts in an animal model of antibiotic treatment to determine whether antibiotic use favors pathogenic bacteria. We utilized next-generation sequencing and in-house metagenomic assembly and taxonomic assignment pipelines on the fecal microbiota of a urinary tract infection mouse model with and without antibiotic treatment. Antibiotic therapy decreased the number of detectable species of bacteria by at least 20-fold. Furthermore, the gut microbiota of antibiotic treated mice had a significant increase of opportunistic pathogens that have been implicated in nosocomial infections, like Acinetobacter calcoaceticus/baumannii complex, Chlamydia abortus, Bacteroides fragilis, and Bacteroides thetaiotaomicron. Moreover, antibiotic treatment selected for antibiotic resistant gene enriched subpopulations for many of these opportunistic pathogens. Oral antibiotic therapy may select for common opportunistic pathogens responsible for nosocomial infections. In this study opportunistic pathogens present after antibiotic therapy harbored more antibiotic resistant genes than populations of opportunistic pathogens before treatment. Our results demonstrate the effects of antibiotic therapy on induced dysbiosis and expansion of opportunistic pathogen populations and antibiotic resistant subpopulations of those pathogens. Follow-up studies with larger samples sizes and potentially controlled clinical investigations should be performed to confirm our findings.
Exploring the Factors that Affect the Frequency of Use of Ridehailing and the Adoption of Shared Ridehailing in California

This study explores the factors that affect the use of ridehailing services (Uber, Lyft) as well as the adoption of shared (pooled) ridehailing (UberPool, Lyft Share) using data collected in Califo...
Effect of grain orientation on the compressive response of highly oriented MAX phase Ti3SiC2

Abstract The MAX phases comprise of a group of layered ternary carbides that exhibit unique mechanical properties which bridge the gap between their metal and ceramic constituents. To study the effects of the global grain orientation, Ti, Si and TiC powders were hot pressed to synthesize highly oriented bulk Ti3SiC2. X-ray diffraction (XRD) was used to verify the grain orientation and a Lotgering factor of 0.87 with respect to the c-axis was obtained. Prepared Ti3SiC2 samples have been compressed in two orientations, loading along the c-axis ( ∥ c-axis) and perpendicular to the c-axis ( ⊥ c-axis) at 10 − 3 s − 1 using a standard load frame and at 10 2 s − 1 using a Kolsky (split-Hopkinson) bar. The average compressive strength along the ⊥ c-axis orientation was 761 MPa under quasi-static conditions and 987 MPa under dynamic loading, exhibiting a 30% increase on average. The ∥ c-axis orientation exhibited no rate dependence in compressive strength; however both orientations exhibited an increase of strain at failure under dynamic conditions by over 0.5%, on average. The orientation-dependent failure behavior at different strain rates were examined using high-speed imaging and 2D digital image correlation (DIC) during loading and via scanning electron microscopy (SEM) post-mortem. Results indicate that the ⊥ c-axis fracture surface exhibited a mixture of transgranular and intergranular cracks, kink bands and delaminations, whereas ∥ c-axis was limited to a combination of intergranular and transgranular cracks. Such fracture distinctions due to the availability (or lack thereof) for kink band formation appear to be responsible for the anisotropic compressive behavior.
Material pairing and selection considerations for thermoelectric cooling devices with components dissimilar to Bi2Te3 based alloys

Abstract Bi2Te3 based alloys used in commercial thermoelectric devices today remain to be state-of-the-art in material performance. However, as new materials are emerging with merits in other aspects, it is necessary to consider how to construct cooling devices with these new materials effectively. In this paper, a numerical method based on one dimensional transport equations and the concept of relative current density is used to simulate performances of devices under optimized geometry and operation conditions. The materials' Seebeck coefficients α are allowed to vary within a realistic range while their zTs are kept constant. It is found that when the two legs are of similar zTs, individual properties have very little influence on device performance at small ΔT, and zT is the only metric to gauge the optimum performance. At large ΔT (relative to maximum achievable ΔT) the α profile has a moderate influence. When two legs have different zTs, device performance will be notably affected by the Seebeck coefficients, especially their magnitudes. This work indicates the limitation of using only zT when comparing different materials’ potential in real devices. General guidance is provided on how to choose materials for each leg for a practical cooling device using emerging new materials.
Supply response in Indian dairying

Owing to several price and non-price factors, India’s dairy sector has grown remarkably in the past four decades. In this paper, we assess relative contributions of such factors to the growth of diary sector. Our results showed that dairying, in terms of both animal stock and yield, is not much responsive to prices of output as well as inputs. However, in the long run, the yield responds positively to technological change in animal breeding, feed supplies, veterinary services and markets. These findings lead us to argue that the dairy policy should focus on pushing up adoption of yield-enhancing technologies, provision of animal health, breeding and extension services, and strengthening of market linkages.
Electron-electron double resonance detected NMR spectroscopy using ensemble NV centers at 230 GHz and 8.3 T

The nitrogen-vacancy (NV) center has enabled widespread study of nanoscale nuclear magnetic resonance (NMR) spectroscopy at low magnetic fields. NMR spectroscopy at high magnetic fields significantly improves the technique’s spectral resolution, enabling clear identification of closely related chemical species. However, NV-detected NMR is typically performed using AC sensing through electron spin echo envelope modulation, a hyperfine spectroscopic technique that is not feasible at high magnetic fields. Within this paper, we have explored an NV-detected NMR technique for applications of high field NMR. We have demonstrated optically detected magnetic resonance with the NV Larmor frequency of 230 GHz at 8.3 T, corresponding to a proton NMR frequency of 350 MHz. We also demonstrated the first measurement of electron–electron double resonance detected NMR using the NV center and successfully detected 13C nuclear bath spins. The described technique is limited by the longitudinal relaxation time ( T1), not the transverse relaxation time ( T2). Future applications of the method to perform nanoscale NMR of external spins at 8.3 T and even higher magnetic fields are also discussed.
Perceptions of e-cigarette harm among cancer survivors: Findings from a nationally representative survey

Abstract Background The growth in e-cigarette use may be driven by the perception that they are a safer, healthier alternative to conventional cigarettes. However, their long-term health implications are not well known and use is discouraged by most cancer societies. It is currently unclear how cancer survivors perceive the risks associated with e-cigarette and how this may influence use in this population. Methods A cross-sectional analysis was conducted using the Health Information National Trends Survey (HINTS) (Years 2017–2019). Our primary study outcome was the perception of harm associated with e-cigarettes compared to traditional cigarettes among adults with and without a self-reported history of cancer. We used logistic regression analyses assessing the association of a cancer history with the perception that e-cigarettes are as much or more harmful than cigarettes. Results A total of 11,846 respondents (weighted population estimate 243,728,483) were included. Of these, 26.6% reported a history of cancer. The proportion of cancer survivors who perceived e-cigarettes to be as much or more harmful than conventional cigarettes was similar to non-cancer respondents (70.6% vs 68.3%, P = 0.35). There was no difference in perception of harm among cancer and non-cancer respondents, adjusted for sociodemographic factors (OR 0.82, 95% CI 0.6–1.1). Past (OR 9.06, 95% Cl 5.06–16.20) and never e-cigarette use (OR 23.40, 95% Cl 13.56–40.38) as well as having a history of cardiopulmonary disease (OR 1.28, 95% Cl 1.05–1.56) was associated with higher odds of perceiving e-cigarettes to be as much or more harmful. Conclusion Cancer survivors commonly perceive e-cigarettes to be as much or more harmful than traditional cigarettes though these findings are similar to perceptions among adults without a history of cancer. There is a strong association with avoidance of e-cigarette products among those who perceive them to be harmful.
Direct Peritoneal Resuscitation in Trauma Patients Results in Similar Rates of Intra-Abdominal Complications.

Background: Trauma patients undergoing damage control surgery (DCS) have a propensity for complicated abdominal closures and intra-abdominal complications. Studies show that management of open abdomens with direct peritoneal resuscitation (DPR) reduces intra-abdominal complications and accelerates abdominal closure. This novel study compares intra-abdominal complication rates and the effect of DPR initiation in patients who received DPR and those who did not. Patients and Methods: A retrospective chart review was performed on 120 patients who underwent DCS. Fifty patients were identified as DCS with DPR, and matched to 70 controls by gender, race, age, body mass index (BMI), past medical history, mechanism of trauma, and injury severity score. Results: The two groups of patients, those without DPR (-DPR) and those with DPR (+DPR), were similar in their characteristics. The +DPR group was more likely to have a mesh closure than the -DPR (14% and 3%; p = 0.022). The +DPR group took longer to have a final closure (3.5 ± 2.6 days vs. 2.5 ± 1.8; p = 0.020). Infection complications and mechanical failure of the closure technique were similar among the two groups. Timing of DPR initiation had no effect on closure type but did statistically increase the number of days to closure (initiation at first operation 2.8 ± 1.8 days vs. initiation at subsequent operations 6.0 ± 3.3 days; p ≤ 0.001). Conclusions: The use of DPR did not result in different outcomes in trauma patients. Therefore, traditional resuscitative measures for DCS may not be inferior to DCS with DPR. When choosing to use DPR, initiating it at the first operation could reduce the number of days to closure.
mRNA usage during Drosophila melanogaster embryonic development. Analysis of nine cloned DNA segments.

Abstract A set of nine phage lambda clones containing inserts from Drosophila melanogaster which are complementary to cDNA made from oocyte poly(A)+ RNA were selected from a larger group. These cloned elements code for a range of middle abundant RNA sequences which show no appreciable change in abundance during Drosophila embryogenesis. Seven of the nine clones are complementary to two oocyte RNAs, one to three RNAs and one to four RNAs. This study describes the changes that occur in these RNAs during embryonic development in the polysomal and non-polysomal fraction, and in the poly(A)+ RNA and poly(A)− RNA fraction. In all nine of these clones, greater than 70% of the complementary RNA is found in the polysomal region of a sucrose gradient. This proportion increases somewhat during development. Specific changes have been found during development in the proportion of RNA that is poly(A)+. Depending to the cloned sequence, this proportion may increase, decrease, or remain unchanged. For those clones that show a change, most of this change occurs between 8 and 19 h of development. Our data suggest, furthermore, the presence of a class of non-adenylated RNA being utilized during embryogenesis.
Electrophoretic analysis of the surface components of autoagglutinating surface array protein-positive and surface array protein-negative Aeromonas hydrophila and Aeromonas sobria.

The protein and lipopolysaccharide (LPS) compositions of 10 autoagglutinating Aeromonas hydrophila and Aeromonas sobria strains were studied; one group consisted of five serogroup O:11 strains that contained an S layer, while a second group was composed of diverse serogroups that were S layer negative by transmission electron microscopy. All serogroup O:11 strains were found to contain a predominant 52,000- to 54,000-molecular-weight protein that was present on both whole-cell and outer membrane protein profiles; this protein was found to be glycine extractable under low-pH (pH 4) conditions and was identified as the surface array protein. LPS analysis revealed that all O:11 strains exhibited homogeneous-length O-polysaccharide side chains characterized primarily by two or three major bands. In contrast, S-layer-negative autoagglutinating strains of other serogroups lacked this predominant surface array protein, and silver stain analysis of LPS indicated that such profiles mainly consisted of core antigens and were deficient in or devoid of O-polysaccharide side chains. These collective results offer potential explanations for observed differences between these two groups in virulence, disease spectrum, and pathogenic properties. Images
S-nitrosothiols (SNO) imported through LAT1 (L-type amino acid transporter type 1) ameliorates phagocytosis in alveolar macrophages and neutrophils (MUC5P.868)

Phagocytosis is a receptor mediated process where cytoskeletal rearrangement occurs to internalize an organism or particles. Macrophages and neutrophils have this potential as they form the first line of defense in any immune response. During lung inflammation, neutrophils and monocytes are freshly recruited; infiltrating neutrophils outnumber other cells but are short lived. As a result, more focus is on macrophages. Our study was the first to describe LAT1 expression in macrophages. We wanted to see the expression of LAT1 and its effects on SNO uptake in neutrophils. We administered LPS (50µg/kg) intratracheally to induce inflammation in juvenile rats. After 24hrs, BALF was collected by intratracheal aspiration, cells were isolated and enumerated. LAT1 expression was observed in neutrophils, monocytes, red blood cells and macrophages. When these cells were exposed to 100 µm of CysNO, neutrophils and macrophages exhibited remarkable phagosomes, rapidly engulfed particles and other senescing neutrophils. These properties were not observed when L-Leu or JPH 203 (competitor and inhibitor) were used. We observed neutrophils cannibalizing senescing neutrophils and neutrophil clearance by macrophages. This was a preliminary observation and further studies are underway. We propose that s-nitrosylation is involved in post translational modifications of some key signaling and adaptor proteins that may be of therapeutic significance in immune response.
Mapping Conceptual Models to Database Schemas

From the beginning, a primary objective of conceptual modeling has been to generate good database schemas. This chapter surveys and explains the principles and practices of algorithmically mapping conceptual models to database schemas. An important unifying theme is that the underlying principles are independent of conceptual-modeling languages and notation. Although illustrated mainly in terms of the entity-relationship model, the chapter explains and illustrates the application of the mapping principles to extended entity-relationship models, the unified modeling language, and generic conceptual-model hypergraphs. Besides explaining conceptual-model-independent mapping rules, the chapter also addresses normalization issues, explaining both the map-then-normalize approach and the normalize-then-map approach to schema normalization. In addition to mapping conceptual models to flat relations for standard relational databases, the chapter also shows how to map conceptual models to nested relations applicable for object-based and XML storage structures.
Particle dynamics in a hydrodynamic separator subject to transient rainfall‐runoff

[1] Analysis of unit operations to separate particulate matter (PM) transported by urban drainage is challenged by coupled hydrologic and mass transport and is commonly based on statistical flow indices. In this study the response of a hydrodynamic separator (HS) to unsteady runoff is modeled with computational fluid dynamics (CFD). Flow is modeled by a k-ɛ model of turbulence with Lagrangian unsteady tracking for particle size distributions (PSDs). CFD results reproduced HS-captured PM mass within 10%. Validated unsteady CFD results are compared to steady flow and PM event mean concentrations, indicating that event-based flow statistics do not represent unsteady HS behavior. Mean and median flows underestimate effluent PM mass, while peak flow overestimates to a lesser magnitude depending on hydrologic and PM coupling. Unsteady flow and PSD coupling in the CFD model yield accurate predictive capability for PM separation by a physically validated unit operation (HS) compared to common event-based flow statistics. While steady flow indices do not reproduce PM behavior for unit operations loaded by unsteady urban drainage, such indices are pragmatic and heuristic for initial phase pilot-scale testing.
Transfer RNA involvement in chlorophyll biosynthesis.

Porphyrin-containing molecules, such as hemes and chlorophylls, are key components of respiratory and photosynthetic metabolism. The tetrapyrrole rings of these molecules are formed via a branched biosynthetic pathway from the condensation of the important five-carbon intermediate 5-aminolevulinic acid (δ-aminolevulinic acid, ALA). The central role of ALA in porphyrin biosynthesis is underscored by the observation that it is a major point for regulation of heme and chlorophyll synthesis in prokaryotes, yeast, algae, plants, and in avian and mammalian cells (Beale and Weinstein, 1990; Jordan, 1990; Labbe-Bois and Labbe, 1990). The biosynthesis of ALA has recently attracted considerable research interest because of the discovery, initially made in plants, that one pathway for its biosynthesis requires an unusual involvement of a transfer RNA (tRNA). In this review we shall focus on various aspects of the required tRNA.(e.g., its characterization, role in the pathway, regulation, and involvement in other metabolic processes), and the enzymes involved in this tRNA-dependent formation of ALA. Most of the progress in this area has involved plant experimental systems; however, it has become increasingly apparent in the last year that the tRNA-dependent formation of ALA is also widely distributed among the eubacterial and archaebacterial kingdoms. Since the enzymes and the mechanisms involved in the tRNA-dependent formation of ALA appear to be remarkably similar in plants and bacteria, we shall also discuss the recent rapid progress made in several bacterial systems. Other reviews have dealt with the development of this research area from a historical perspective and in relation to the overall process of porphyrin biosynthesis (Beale, 1990; Beale and Weinstein, 1990; Castelfranco and Beale, 1983; Jordan, 1990; Kannangara, 1991; O’Neill and Soil, 1990a; von Wettstein, 1991).
Plant biodiversity on shortgrass steppe after 55 years of zero, light, moderate, or heavy cattle grazing

Shortgrass steppe rangeland near Nunn, Colorado, USA, has been lightly,moderately, or heavily grazed by cattle, or protected from grazing inexclosures, for 55 years. Plant species biodiversity and evenness were greatestin lightly- and moderately-grazed pastures. Both pastures weredominated by the warm-season shortgrass Boutelouagracilis, but the cool-season midgrasses Pascopyrumsmithii and Stipa comata contributedsignificantly to biomass production on the lightly-grazed pasture, asthey did in the exclosures. Diversity was least in the exclosures, which werestrongly dominated by the cactus Opuntia polyacantha.Buchloe dactyloides, another warm-seasonshortgrass, and Bouteloua gracilis were co-dominantsunder heavy grazing, and diversity was intermediate. Plant community structureand diversity were controlled by selective grazing by cattle and soildisturbance by cattle and rodents. Shortgrass steppe moderately or heavilygrazed by cattle was similar to and probably as sustainable as steppe grazed formillenia by bison and other wild ungulates.
Fluence Rate Effects in Photodynamic Therapy of Multicell Tumor Spheroids

Abstract EMT6/Ro spheroids approximately 500 µm in diameter were subjected to photodynamic therapy administered at various incident radiation fluence rates. Following 24 h incubation with 10 µg/ml Photofrin, groups of spheroids were irradiated at 630 nm with an identical fluence of 60 J/cm2, delivered at fluence rates ranging from 25 to 200 mW/cm2. After treatment, spheroids were dissociated, cell yields were determined, and surviving cells were assayed for their colony-forming ability. A surviving fraction was calculated for each treatment group by computing the product of the fractional cell yield and the plating efficiency. The results exhibit a strong dependence on the fluence rate, with surviving fractions decreasing from approximately 0.5 to 0.07 as the incident fluence rate was lowered from 200 to 25 mW/cm2. These data were analyzed using a mathematical model of photochemical oxygen consumption in spheroids undergoing photodynamic therapy. Calculations showed that therapy-induced oxygen consumption creates hypoxic volumes within which cells would be protected from singlet oxygen-mediated damage and that the magnitude of these hypoxic volumes depends on the radiation fluence rate. The fluence rate dependence of the spheroid cell survival was consistent with such an interpretation.
Fundamental concepts in communication

Designed for advanced undergraduate or graduate courses in communications in electrical engineering departments, this book presents a mathematical description of the essential areas that define the field of communication. Among the topics covered are: signal theory and signals in linear vector spaces; noise and its effects; information theory and coding; representation of information; statistical detection theory; communication performance in AWGN; error-control coding; rate-distortion theory and achieving real-world performance; the algebraic structure of communication signals in Hilbert space and over Galois fields; the role and contribution of signal space metrics to communication performance; the distinction between the performance-related algebraic structure of codes and alogorithmics details; and rate-distortion theory and its use in balancing trade-offs.
DWDM nanophotonic interconnects: toward terabit/s chip-scale serial link

Dense wavelength-division multiplexing (DWDM) is a promising technique to increase capacity of nanophotonic interconnects for chip-scale serial links. This paper describes recent progress in DWDM nanophotonic interconnects based on silicon microring resonators, including a five-channel DWDM transmitter using a quantum dot (QD) comb laser and carrier-injection modulators, as well as self-adaptive CMOS transmitter for hybrid CMOS and photonic chips integration.
Maternal death due to stroke

Abstract Maternal deaths due to stroke often are included in those nonpreventable tragedies rarely encountered in obstetric practice. Careful analysis of 29 stroke deaths indicates, however, that perhaps 35 per cent are avoidable. This report defines those areas in which increased effort could be expected to result in significant reduction in maternal death from this cause.
Outcomes of a Quality Improvement Project Examining Early Childhood Caries and Improving Identification of At Risk Patients in a Pediatric Medical Home Setting

Early childhood caries (ECC) is a widespread childhood disease that disproportionately affects children with disabilities, those in lower-income households and minority children. The American Academy of Pediatrics (AAP) recommends that all children be screened for ECC and referred to a dentist by the age of one. This quality improvement project took place at a hospital-affiliated pediatric clinic. A caries risk screening tool was implemented at 9-, 12-, and 18-month well child check-ups for 3 months. A retrospective chart review was performed for comparison purposes. The quality improvement project indicated improvement in identification of children at high-risk for ECC.
Matrix infrared study of low-energy electron and alkali cation impact on CCl4

Abstract Low-energy (30–200 eV) electron bombardment of Ar/CCl4 (400/1) samples during deposition at 12 K has produced and trapped CCl2, CCl3, CCl3+, CCl4+ and Cl3+ as well as C2Cl4. The neutral products became more dominant as the electron energy was increased. Using Li+ and Cs+ ions instead of electrons gave the same neutral and ionic products. Although increasing the ion energy increased the relative yield of neutral products, as with electrons, positively charged products remained dominant with cation bombardment. At very low Li ion energies, Cl abstraction was a major process as evidenced by a relatively large yield of CCl3+ and a weak LiCl absorption.
Near-terminus axonal structure and function following rat sciatic nerve regeneration through a collagen-GAG matrix in a ten-millimeter gap.

The objectives of this study were to evaluate the regenerated axon structure at near-terminal locations in the peroneal and tibial branches 1 year following implantation of several tubular devices in a 10-mm gap in the adult rat sciatic nerve and to determine the extent of recovery of selected sensory and motor functions. The devices were collagen and silicone tubes implanted alone or filled with a porous collagen-glycosaminoglycan matrix. Intact contralateral nerves and autografts were used as controls. Nerves were retrieved at 30 and 60 weeks postoperatively for histological evaluation of the number and diameter of regenerated axons proximal and distal to the gap and in the tibial and peroneal nerve branches, near the termination point. Several functional evaluation methods were employed: gait analysis, pinch test, muscle circumference, and response to electrical stimulation. A notable finding was that the matrix-filled collagen tube group had a significantly greater number of large-diameter myelinated axons (≥6 μm in diameter) in the distal nerve branches than any other group, including the autograft group. These results were consistent with previously reported electrophysiological measurements that showed that the action potential amplitude for the A fibers in the matrix-filled collagen tube group was greater than for the autograft control group. Functional testing revealed the existence of both sensory and motor recovery following peripheral nerve regeneration through all devices; however, the tests employed in this study did not show differences among the groups with regeneration. Electrical stimulation in vivo showed that threshold parameters to elicit muscle twitch were the same for reinnervating and control nerves. The investigation is of importance in showing for the first time the superiority of a specific fully resorbable off-the-shelf device over an autograft for bridging gaps in peripheral nerve, with respect to the near-terminus axonal structure. J. Neurosci. Res. 60:666–677, 2000 © 2000 Wiley-Liss, Inc.
Pore size control and electrochemical capacitor behavior of chemically activated polyacrylonitrile – Carbon nanotube composite films

Abstract Activated polyacrylonitrile (PAN)/carbon nanotube (CNT) composite film based electrodes have been prepared by chemical activation with potassium hydroxide for electrochemical capacitors. This paper analyses the following aspects of specific capacitance, pore size distribution and surface area: influence of activation temperature, molarity of activating agent, composition of PAN/carbon nanotube precursor films and electrolytes. A maximum value of specific capacitance of ∼302 Fg−1 was achieved for the samples activated at 800 °C. Energy density for PAN/CNT 80/20 sample when tested with ionic liquid/organic electrolyte system was as high as ∼22 W h kg−1. Pore size control predominantly below 5 nm was observed in these activated PAN samples. Data analysis showed that micropores make a significant contribution to the capacitance performance of these materials in both 6 M KOH as well as in BMIMBF4/acetonitrile electrolytes.
EFFECTS OF OFF-DIAGONAL DISORDER ON SOLITON- AND POLARON-LIKE STATES IN TRANS-POLYACETYLENE

We report on some exact results we have obtained that show off-diagonal disorder can have a significant effect on the Peierls band edges of polyacetylene as well as polaron-like gap states in this system. Our results also prove that such disorder leaves many of the more important properties of soliton-like defects largely unaffected.
Inheritance and allelism of Russian wheat aphid resistance in several wheat lines

The Russian wheat aphid (RWA), Diuraphis noxia (Mordvilko) has caused serious reduction in wheat production in 17 Western states of the United States since 1986. Inheritance of resistance to RWA in seven wheat lines and the allelism of the resistance genes in these lines with three known resistance genes Dn4, Dn5, and Dn6 were studied. The seven resistant lines were crossed to a susceptible wheat cultivar 'Carson' and three resistant wheats: CORWA1 (Dn4), PI 294994 (Dn5), and PI 243781 (Dn6). Seedlings of the parents, F 1 , and F 2 were screened for RWA resistance in the greenhouse by artificial infestation. Seedling reactions were evaluated 21-28 days after the infestation using a 1-9 scale. The resistance level of all the F 1 hybrids was similar to that of the resistant parent, indicating dominant gene control. Only two distinctive classes were present and no intermediate types were observed in the F 2 population, suggesting qualitative, nonadditive gene action, in which the presence of any one of the dominant alleles confers complete resistance to RWA. Resistance in CI 2401 is controlled by two dominant genes. Resistance in CI 6501 and PI 94365 is governed by one dominant gene. Resistance in PI 94355 and PI 151918 may be conditioned by either one dominant gene or one dominant and one recessive gene. No conclusion can be made on how many resistance genes are in AUS-VA1-F 3 , since the parent population was not a pure line. Allelic analyses showed that one of resistance genes in CI 2401 and PI 151918 was the same allele as Dn4, the resistance gene in CI 6501 was the same allele as Dn6, and AUS-VA1-F 3 had one resistance gene which was the same allele as one of the resistance genes in PI 294994. One non-allelic resistance gene different from the Dn4, Dn5, and Dn6 genes in CI 2401, PI 94355, PI 94365, and PI 222668 was identified and should be very useful in diversifying gene sources in wheat breeding.
Wetland Simulation Model for Nitrogen, Phosphorus, and Sediments Retention in Constructed Wetlands

Steamboat Creek, Washoe County, Nevada, is considered the most polluted tributary of the Truckee River, therefore the reduction of nutrients from the creek is an important factor in reducing eutrophication in the lower Truckee River. Restoration of the wetlands along the creek has been proposed as one method to improve water quality by reducing nutrient and sediments from non-point sources. This study was aimed to design a simulation model wetlands water quality model (WWQM) that evaluates nitrogen, phosphorus, and sediments retention from a constructed wetland system. WWQM is divided into four submodels: hydrological, nitrogen, phosphorus, and sediment. WWQM is virtual Visual Basic 6.0 program that calculates hydrologic parameters, nutrients, and sediments based on available data, simple assumptions, knowledge of the wetland system, and literature data. WWQM calibration and performance was evaluated using data sets obtained from the pilot-scale constructed wetland over a period of four and half years. The pilot-scale wetland was constructed to quantify the ability of the proposed wetland system for nutrient and sediment removal. WWQM simulates nutrient and sediments retention reasonably well and agrees with the observed values from the pilot-scale wetland system. The model predicts that wetlands along the creek will remove nitrogen, phosphorus, and sediments by 62, 38, and 84 %, respectively, which would help to reduce eutrophication in the lower Truckee River.
Template matching based on rank-order operations

Linear correlation techniques are useful approaches for template matching. However, they are computationally intensive since large numbers of multiplications are involved in their calculation. This paper introduces a family of rank-order-based criteria (ROBC) which are multiplier free and do not depend on the local average of the image/template. The most primitive member of this family has properties analogous to the properties of the normalized linear correlation. Hence, we call it normalized min-max cross-correlation (NMCC). Experimental results are presented that describe the performance of the introduced criteria in the presence of Gaussian and impulsive noise. These experiments show that the NMCC features sharp and robust indications in the presence of Gaussian noise. Other members of the ROBC family with more rank order terms also are robust with respect to impulsive noise.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
CHANGES IN MEMORY, ELECTROPHYSIOLOGY, NEUROCHEMISTRY AND NEURONAL ULTRA‐STRUCTURE AFTER DEUTERON IRRADIATION OF THE BRAIN IN C57B1/10 MICE

— Changes in memory, electrocorticograms (ECoG), protein, DNA, RNA, neurotransmitters, enzyme activity and neuronal ultrastructure were examined after deuteron irradiationof the brain in C57B1/10 mice. Twenty animals served as sham-irradiated controls, while three irradiated groups received a dose of either 500, 5000 or 10,000 rads covering an area of 9 × 5 mm over the dorsal surface of the brain and extending to a depth of 2 mm from the skull. The 10,000 rad group differed significantly in retention of spontaneous locomotor performance and dark maze exploration during a 16-month post-irradiation period. Desynchronization with an overall amplitude reduction of both spontaneous and light evoked ECoG was observed in the 10,000 rad group. There was a dose-dependent decrease in protein, DNA and RNA content but not in their concentrations. Brain irradiation resulted in a significant change in content as well as concentration of 5-HT and in acetylcholinesterase activity both per brain and per gram fresh weight. Morphologically, there was a significant reduction in brain and pituitary weight. Histochemical observations indicated a uniform and dose-dependent reduction in vascular alkaline phosphatase activity and a selective decrease in staining for cellular DNA and RNA in different regions of the irradiated tissue of the brain. Electron microscopic comparisons of nuclear and cytoplasmic changes indicated serration of some nuclear membranes in the 10,000 rad group, accumulation of glycogen, numerous phagocytes and formation of multi-lamellar intraneuronal membranes. Prominent synaptic changes were not observed in the remaining neurons within the irradiated tissue of the brain. From the multidisciplinary comparisons it was concluded that deuteron irradiation of the CNS can be used as another approach for relating changes in such unique functions as learning and memory to subcellular and cellular changes in specific regions of the brain.
A veterinary practice simulator based on the integration of expert system and process modeling

Health care delivery systems of all kinds must operate under resource constraints. This gives rise to design issues that are best addressed by engineering methods such as simulation modeling and an...
The evolutionary inheritance of elemental stoichiometry in marine phytoplankton

Phytoplankton is a nineteenth century ecological construct for a biologically diverse group of pelagic photoautotrophs that share common metabolic functions but not evolutionary histories 1 .I n contrast to terrestrial plants, a major schism occurred in the evolution of the eukaryotic phytoplankton that gave rise to two major plastid superfamilies 2‐4 . The green superfamily appropriated chlorophyll b, whereas the red superfamily uses chlorophyll c as an accessory photosynthetic pigment 5 . Fossil evidence suggests that the green superfamily dominated Palaeozoic oceans. However, after the end-Permian extinction, members of the red superfamily rose to ecological prominence. The processes responsible for this shift are obscure. Here we present an analysis of major nutrients and trace elements in 15 species of marine phytoplankton from the two superfamilies. Our results indicate that there are systematic phylogenetic differences in the two plastid types where macronutrient (carbon:nitrogen:phosphorus) stoichiometries primarily reflect ancestral pre-symbiotic host cell phenotypes, but trace element composition reflects differences in the acquired plastids. The compositional differences between the two plastid superfamilies suggest that changes in ocean redox state strongly influenced the evolution and selection of eukaryotic phytoplankton since the Proterozoic era. To examine patterns of variation in biochemical composition, 15 species of marine eukaryotic phytoplankton from five phyla were grown using axenic techniques under identical conditions (19 ^ 1 8C; 12 h light/dark cycle; 250 mmol photons m 22 s 21 ).