cssi/SciSciGPT-SciSciNet huggingface dataset:
Energetic Ion Injections Inside Geosynchronous Orbit: Convection- and Drift-Dominated, Charge-Dependent Adiabatic Energization (W = qEd).

Particle injection, a major mode of plasma transport and energization throughout the magnetosphere, has been studied for decades. Nonetheless, the physical processes that lead to the acceleration and transport of very energetic ions in the inner magnetosphere during injection events are still under debate. In this paper, we analyze several injection events occurring near the Van Allen Probes apogee. Our analysis shows that the highest energy of an injected ion population depends on the charge state of that population. We show that most of the helium injected is doubly ionized (He++), while oxygen charge states are consistent with the presence of both ionospheric (O+) and solar wind (O6+) source populations. Based on the findings of our data analysis and with the use of a simple model, we demonstrate that the behavior of each injection of energetic ions near the Van Allen Probes apogee (5 < L < 7 R E) is well explained by simple adiabatic or nearly adiabatic transport within flow channels from higher L (≥10 R E) with velocities at 10 R E ranging between ~200 and 2,000 km/s and falling with inward transport consistent with fixed potential drops across the flow channels. Gradient/curvature drift during transport limits the highest energy/charge observed for each injection at the Van Allen Probes. Even at the highest measured ion energies where gyroradius and scattering effects might be expected to appear, energization depends on charge state but not on ion mass.
Sexual Selection: Why Does it Play Such a Large Role in The Descent of Man ?

The Descent of Man is a strange book. About three-fifths is not on human beings at all, but an extended discussion of Charles Darwin’s secondary mechanism of sexual selection. I argue that although the book is surely a little unbalanced, overall the discussion fits into Darwin’s strategy of explaining and extending his thinking on evolution, and that truly it marks no significant theoretical shift from his earliest thinking about the nature and causes of evolution. Darwin saw the evolution of human beings at one with the evolution of all organisms.
Projecting Propbank Roles onto the CCGbank

This paper describes a method of accurately projecting Propbank roles onto constituents in the CCGbank and automatically annotating verbal categories with the semantic roles of their arguments. This method will be used to improve the structure of the derivations in the CCGbank and to facilitate research on semantic role tagging and broad coverage generation with CCG.
Significant predictors of mathematical literacy for top-tiered countries/economies, Canada, and the United States on PISA 2012: Case for the sparse regression model

Background National ranking from the triennial Programme of International Student Assessment (PISA) often serves as a barometer of national performance and human capital. Though excessive student- and school-level covariates (n > 700) may prove intractable for traditional least-squares estimate procedures, shrinkage methods may be more suitable for subset selection. Aims With a focus on the United States, this paper proposes sparse regression for PISA 2012 to discover salient student- and school-level predictor variables for mathematical literacy achievement. Sample The sparse regression analysis was conducted on 10 top-tiered OECD countries/economies, Canada, and the United States in mathematical literacy on the 2012 PISA. Two- and three-level hierarchical regression analyses were performed on Canadian and US students (N = 26,522) along with five of the ten top-tiered countries/economies (N = 58,385). Methods Using the 'least absolute shrinkage and selection operator' (LASSO) technique, the study (1) identified salient predictor variables of mathematical literacy performance for the top-tiered countries/economies, Canada, and the United States and (2) used these salient variables to perform two- and three-level hierarchical regression on data from Canada and the United States along with five top-tiered countries/economies. Weights and replicates were used to account for complex sample design. A weighted, two-level confirmatory factor analysis was performed to identify latent constructs. Missing data were handled through multiple imputation. Results Separate two-level hierarchical models accounted for 32-35% student-level and 58-70% school-level variance in Canada and the United States, respectively; three-level models accounted for 33% of level-one variance, 62-65% level-two variance, and 13-44% of level-three variance for the US/Canada and US/Canada/top-tiered students, respectively. Following top-tiered countries/economies, Canadian students had high levels of self-efficacy, were more likely to encounter advanced concepts in class, were less activity/small group-centred, and were more likely to consider truancy a learning hindrance. Factor analyses revealed a positive relation with rigour and class organization (teacher-centred) for top-tiered countries and Canada, though not for the United States. For all countries, there was a strong relation between rigour and self-beliefs. Conclusion Compared to top performers, a less rigorous curriculum, coupled with class and school factors, may explain lag in US performance.
Managing Postoperative Infection following Breast Reconstruction with the Sientra AlloX2 Tissue Expander.

Background Implant-based breast reconstruction is the most common reconstructive modality in the United States. Significant advances in surgical technique and technology have resulted in improvement of clinical outcomes. A recent innovation has been the introduction of a tissue expander with an integral drain that permits access to the periprosthetic space. A new use for this drain port is presented in patients with postoperative surgical-site infection. Methods Patients who underwent staged implant-based breast reconstruction with the Sientra AlloX2 tissue expander and experienced postoperative infection that warranted inpatient management with intravenous antibiotics were included in the study. The integral drain port was used in these patients to perform washout of the periprosthetic space at the bedside. The ability to salvage the tissue expander in the setting of infection without the need for surgical revision in the operating room was determined. Results Of 31 patients who underwent a total of 52 staged breast reconstructions with the Sientra AlloX2 tissue expander, 3 patients (8.7%) with a mean age of 50.3 years (range, 34-76 years) and mean body mass index of 23.3 kg/m2 (range, 22.3-24.1 kg/m2) met inclusion criteria. Salvage of the device with successful progression through expansion and eventual expander-implant exchange was achieved in 2 patients. One patient failed the salvage attempt and required removal of the device. Conclusion Using the integral drain port of the AlloX2 tissue expander has the potential for device salvage in a subset of patients with surgical-site infection without the need for surgical revision.
Is the TechnoFix In?: Research on the Ecological Impact of Solar Power

This project aims to investigate whether the use of solar power results in net reductions in carbon emissions and other environmental contaminants and, more broadly, whether such a thing as “environmentally balanced” technological innovation is possible under the framework of capitalism. I conduct a review of existing research and literature on the costs, benefits, and externalities involved in the generation, collection, and distribution of solar power, and compile the results to understand the current state of the art, and its impacts. My findings indicate that the byproducts and unintended consequences of the technologies used in various forms of solar power (e.g., photovoltaics, concentrated solar lensing, lithium-ion batteries) are far greater than are widely understood, and that this is a necessary consequence of the economic system via which they are developed. However, I argue that this does not mean that we ought not to invest time and effort toward the development of these technologies, rather that we must do so outside of a framework that is predicated on growth, expansion, consumption, “innovation.” We must work to shift the values by which we conceive and develop environmental technologies, in order to build a system wherein we can do so not just “sustainably,” but ethically and in a way that respects our entanglement with the rest of the natural world.
Fibrinogen Proteolysis and Coagulation System Activation during Thrombolytic Therapy

Thrombolytic treatment of patients with acute myocardial infarction is now well accepted as the treatment of choice in most settings (24). At this time most data has been accumulated with the use of streptokinase, and this drug has been convincingly demonstrated to reduce mortality (5). Reperfusion is achieved in 45–75% of patients, with direct intracoronary administration being slightly more effective than administration by the intravenous route (25). Some problems remain, bleeding is significant and rethrombosis continues to be an obstacle (7).
Racial and ethnic trends in unintentional carbon monoxide poisoning deaths

Objective Government programs have attempted to impact a recognized elevated risk for carbon monoxide (CO) poisoning among minority racial and ethnic groups. This study sought to describe U.S. mortality due to unintentional, non-fire-related CO poisoning, examining the distribution and trends by race and ethnicity. Methods CDC Wonder was used to extract and analyze data on all U.S. resident deaths from unintentional CO poisoning from 2000-2017, categorizing them by year, race, ethnic origin and gender. Results The absolute number of unintentional CO deaths decreased from about 450 to 380 per year during the period studied, a number near totally accounted for by the decrease in deaths occurring among non-Hispanic/Latino whites. The number of deaths among the remainder of the population did not significantly change. However, greater growth in minority populations resulted in a similar decline in the mortality rate between non-Hispanic/Latino whites and the combined minority population. The decline in combined minority death rate resulted from a decrease in the Hispanic/Latino white rate. Death rate did not decline in the black or African American population. Conclusions All minority groups continue to display a disproportionate number of unintentional non-fire-related CO poisoning deaths compared to non-Hispanic/Latino whites. The decrease in U.S. deaths from unintentional non-fire-related carbon monoxide poisoning from 2000-2017 is accounted for by a decrease in non-Hispanic/Latino white deaths. While numbers of such deaths among minority groups have not changed since 2000, increases in the size of minority populations have resulted in a declining crude death rate for Hispanic/Latino whites.
Screening for Colorectal Cancer in Asymptomatic Average-Risk Adults: A Guidance Statement From the American College of Physicians.

Colorectal cancer is the second leading cause of cancer-related death among adults in the United States. This guidance statement from the American College of Physicians aims to assist clinicians re...
Psychosocial Issues and Child Abuse

This chapter covers all aspects of the psychosocial issues that confront the pediatrician: divorce, puberty, sibling rivalry, separation anxiety, adoption, foster care, and children’s understanding of death and their stages of grief. Specific medical conditions discussed include enuresis, encopresis, pain, psychosomatic disorders, sleep disorders, night pain, and vulnerable child syndrome (VCS), among others. Other subjects covered are the child’s use of media, chronic illness, the gifted child, and child abuse and neglect.
Identification of Worst Impact Zones for Power Grids During Extreme Weather Events Using Q-learning

Both the frequency and intensity of extreme weather events have been trending higher in recent years, leading to significant infrastructure damage in the electric grid. The impact of these extreme weather events is desired to be analyzed and quantified to help transmission and distribution system operators prepare for and prevent significant damage and subsequent loss of power. In this paper, we develop an approach that models the impact of extreme weather on the grid and identifies the worst impact zone using Q-learning (a reinforcement learning approach). The identification results reveal grid vulnerability to weather events and provide insights for system operators to help achieve optimal resource allocation and crew dispatch to minimize the adverse impacts of extreme weather. Simulation studies are conducted on the IEEE 123-node system to demonstrate the performance of the proposed approach.
A Chaotic Circuit for Producing Gaussian Random Numbers

One of the main applications for chaotic circuits is the production of aperiodic signals with many of the characteristics of noise for secure communications and similar uses. However, the probabili...
Determinants of the Audiometric Notch at 4000 and 6000 Hz in Young Adults.

Background Noise-induced hearing loss (NIHL) is often characterized by the presence of an audiometric notch at 3000-6000 Hz in a behavioral audiogram. The audiometric notch is widely used to investigate NIHL in children and young adults. However, the determinants of the audiometric notch in young adults largely remain unknown. Purpose The study aimed to investigate the determinants of the audiometric notch in young adults. Research Design A cross-sectional design was adopted for the study. Study Sample A sample of 124 adults (38 males and 86 females) aged 18-35 years with normal otoscopic and tympanometric findings was recruited. Data Collection and Analysis Hearing thresholds and real-ear sound pressure levels (RESPLs) were obtained with calibrated ER-3A (Etymotic Research, Elk Grove Village, IL) andTDH-50P receivers (Telephonics, Farmingdale, NY). Distortion-product otoacoustic emissions (DPOAEs) were used to evaluate the cochlear function. The external auditory canal (EAC) length was measured using the acoustical method. Noise exposure background (NEB) was estimated using the Noise Exposure Questionnaire. The notched audiograms were identified using: Phillips, Coles, and Niskar criteria. Results The prevalence of notched audiograms was substantially higher for TDH-50P supra-aural receivers than for ER-3A insert receivers. RESPLs at 6000 and 8000 Hz were the major predictors of notched audiograms for TDH-50P receivers. These predictors explained around 45% of the variance in the notched audiograms. The notched audiograms obtained with TDH-50P receivers showed no association with NEB. Individuals with notched audiograms measured using TDH-50P did not show convincing evidence of cochlear dysfunction as assessed by DPOAEs. Individuals with notched audiograms obtained with TDH-50P receivers revealed an average of shorter EAC and a poorer hearing threshold at 6000 Hz. Conclusions The calibration error in the RESPLs at 6000 and 8000 Hz that are likely to be influenced by the shorter EAC was the major determinant of the notched audiograms when the supra-aural transducers were used to measure hearing thresholds. Therefore, the supra-aural receivers should not be used to estimate the prevalence of NIHL in children and young adults when the less restrictive notch identification criteria are used to identify NIHL. Real-ear calibration techniques that are least influenced by the standing waves in the EAC should be preferred when investigating the prevalence of and risk factors for NIHL in young adults.
Feasibility and clinical utility of cancer whole genome and transcriptome sequencing for pediatric and young adult solid tumors.

3063Background: Next generation sequencing (NGS) assays have accelerated the identification of mutations and potential matched targeted therapies for patients with cancer. However, a significant pr...
Utility of Frailty Assessment in Urologic Stone Surgery: A Review of the Literature.

Introduction & Objective As life expectancy continues to rise, the prevalence of frailty is also increasing. The idea of frailty and its effect on the operative patient has been previously studied,...
Risk of Extreme, Moderate and Late Preterm Birth by Maternal Race, Ethnicity and Nativity

Objectives To explore the relative risks of preterm birth-both overall and stratified into three groups (late, moderate and extreme prematurity)-associated with maternal race, ethnicity and nativity (ie, birthplace) combined. Study design This was a retrospective cross-sectional cohort study of women delivering a live birth in Pennsylvania from 2011-2014 (n=4,499,259). Log binomial and multinomial regression analyses determined the relative risks of each strata of preterm birth by racial/ethnic/native category, after adjusting for maternal sociodemographic, medical comorbidities and birth year. Results Foreign-born women overall had lower relative risks of both overall preterm birth and each strata of prematurity when examined en bloc. However, when considering maternal race, ethnicity and nativity together, the relative risk of preterm birth for women in different racial/ethnic/nativity groups varied by preterm strata and by race. Being foreign-born appeared protective for late prematurity. However, only foreign-born White women had lower adjusted relative risks of moderate and extreme preterm birth compared with reference groups. All ethnic/native sub-groups of Black women had a significantly increased risk of extreme preterm births compared with US born non-Hispanic White women. Conclusions Race, ethnicity and nativity contribute differently to varying levels of prematurity. Future research involving birth outcome disparities may benefit by taking a more granular approach to the outcome of preterm birth and considering how nativity interacts with race and ethnicity.
Feature Selection Algorithms for Mining High Dimensional DNA Microarray Data

The World Heath Organization identified cancer as the second largest contributor to death worldwide, surpassed only by cardiovascular disease. The death count for cancer in 2002 was 7.1 million and is expected to rise to 11.5 million annually by 2030 [17]. In 2009, the International Conference on Machine Learning and Applications, or ICMLA, proposed a challenge regarding gene expression profiles in human cancers. The goal of the challenge was the “identification of functional clusters of genes from gene expression profiles in three major cancers: breast, colon and lung.” The identification of these clusters may further our understanding of cancer and open up new avenues of research.
SU-E-T-03: 3 Year Clinical Experience with the IBA Proton Eyeline

Purpose: Over the past 3 years, more than 50 patients with ocular disease have been treated with a prototype commercial eyeline developed by Ion Beam Applications (IBA). It is particularly crucial for the dosimetry of the machine to be accurate, precise, and reproducible because of the small treatment volumes and several surrounding critical structures. A quality assurance (QA) program has been developed in order to regularly check and record the machine's dosimetry over time. In this study we have summarized and evaluated three years of patient and system QA data for the eyeline prototype. Methods: In order to accurately deliver the prescribed dose to the patient's treatment site, an output model was created based on several machine parameters. This output model, along with the requested system parameters, are regularly checked and recorded by a QA program. 10 standard proton fields have been created which have regular QA performed monthly with a water tank and parallel-plate chamber, and recorded in a database. QA has additionally been performed for each patient-specific treatment field. This is to verify and evaluate the patient output model as well as the system parameters for range&modulation combinations different than the standard QA fields. Results: 140 beam measurements have been analyzed for range, modulation, and output. The range is typically within tolerance, although there are about 6 cases where the system did not perform as expected. The modulation appears to be very stable, always being within tolerance. Output for the standard QA fields are typically within 2.5% from the baseline value. The patient output measurements agree within 2.5% from the model. Conclusion: Overall the eyeline performs well within the tolerances set, and the patient output measurements agree within 2% of the model.
Analysis of large libraries of protein mutants using flow cytometry

Publisher Summary This chapter introduces a flow cytometry, as an extremely useful tool for the quantitative analysis of protein libraries, and for the isolation and characterization of very rare clones. Flow cytometry is a one-dimensional implementation of fluorescence microscopy, where the particles or cells under observation flow in a stream past a light source and optical collection apparatus. Flow cytometers are designed to be easily programmed to collect cells of the desired optical properties, such as light scattering or fluorescence profile, using either a closed cycle or an electrostatic droplet deflection technology. The screening of protein libraries by flow cytometry offers the following advantages: quantitative assays can be performed on large populations, with single cell resolution; and multiple quantitative parameters for each cell can be analyzed simultaneously, including various fluorescence signals and forward, and 90u light scattering. Flow cytometry represents the most advanced library screening tool, in terms of instrument sophistication, throughput, and the degree of enrichment of positive cells. The quantitative nature of flow cytometry makes it an ideal tool for the exploration of protein sequence space and for the evolution of new function.
First Things First: Clarifying Intention

Two decades ago, novelist Robert Pirsig (1974) noted the confusion about what constitutes education. He began with an anecdote about a country church that had been sold and was being used as a bar. Dismayed by the electric beer sign hanging over the building's front entrance, many people complained to church officials-but rather than being outraged, the priest who responded to the criticism was irritated by their misunderstanding of what constitutes a church:
A Recursive Approach For Calculating The Effective Yield On Bonds When Settlement And/Or Expected Maturity Is Other Than An Interest Payment Date.

Standard spreadsheet functions cannot compute bond yields if both the settlement and maturity dates fall on other than an interest payment date. Using reciprocal cell references, the RATE function is enhanced to overcome this limitation. An appendix extends the enhancement procedure to the IRR function. The procedure demonstrated has applications to a wide variety of financial transactions which are structured around an initial cash flow followed by an annuity and a lump sum, for example, a single advance loan with an odd first and/or last payment period and a terminal balloon payment.
Performance Trade-offs for a Multimedia Distributed Application

We have designed and developed an Interactive Remote Instruction (IRI) system to support university-level instruction in a networked environment. The IRI system creates a virtual classroom where all participants have the same experience independent of their spatial location (separated by up to order of 100 km). Participants interact with audio, video, and collaborative tool operation information through a multimedia workstation. In this paper we describe an IRI testbed consisting of Sun Sparcstations 5 running Solaris 2.4 implemented over a local area network. We discuss the performance trade-offs and the scalability of the IRI system by analyzing results obtained during the execution of a test suite on the IRI testbed. The test suite consists of operations such as running a tool on a single workstations, running the tool collaboratively on multiple workstation, and finally running the tool collaboratively along with the display of student and teacher video images and audio. The most important conclusion of this work is that, though some improvements are required, we are able to achieve an acceptable performance within the goals we had established for IRI-required functionalities using moderately price hardware based on current technologies (about \$7K per student workstation). Feasibility means that response time for user commands is no more than twice in the worst case (Mosaic running on a single workstation by itself versus Mosaic running collaboratively on the testbed with multiple video streams and audio added). The results we obtained from this experimentation are being used in the design of a dynamic resource management scheme which will regulate the demand on the IRI system resources to maximize user perception of the quality of the virtual classroom. We briefly describe these and other planned improvements to the IRI system as well.
Evaluation of an energy-based approach and a critical plane approach for predicting constant amplitude multiaxial fatigue life

A new energy-based approach for predicting constant amplitude multiaxial fatigue life is described. The approach is based on cyclic plastic and elastic strain energy densities and takes into account effects of stress-state and mean stresses. A wide range of test data is used to evaluate the approach as well as a critical plane approach based on maximum amplitude of shear strain modified by the maximum normal stress on the plane of maximum shear strain amplitude. Predictive capabilities of both approaches are found to be comparable, with some differences for certain types of multiaxial loading.
Can women without visible pubococcygeal muscle in MR images still increase urethral closure pressures

Abstract Objective The purpose of this study was to determine if the ability to increase maximum urethral closure pressure (MUCP) with a pelvic muscle contraction is impaired in women without pubococcygeal muscle (PCM). Study design This was a cross-sectional study of continent women comparing those with (n = 28) and those without (n = 17) PCM as identified by MR scans. A pelvic muscle contraction was performed simultaneously with recordings of urethral and bladder pressures. Results Eighty-six percent of the women with PCM compared with 41% of the women without could volitionally increase (>5 cm H2O) their MUCP. Those with PCM generated a mean intraurethral pressure rise of 14.0 (10.8) cm H2O, compared with 6.2 (8.7) cm H2O in those without (P = .015). Among women who could produce a visible pressure rise, there was not a statistically significant difference between groups (with PCM = 17.2 [7.8] cm H2O; without PCM = 14.7 [7.5] cm H2O; P = .457). Conclusion Selective women without visible PCM can increase MUCP.
Theoretical Analysis of a Quartz-Enhanced Photoacoustic Spectroscopy Sensor

Quartz-enhanced photoacoustic spectroscopy (QEPAS) sensors are based on a recent approach to photoa- coustic detection which employs a quartz tuning fork as an acoustic transducer. These sensors enable detection of trace gases for air quality monitoring, industrial process control, and medical diagnostics. To detect a trace gas, modulated laser radiation is directed between the tines of a tuning fork. The optical energy absorbed by the gas results in a periodic thermal expansion which gives rise to a weak acoustic pres- sure wave. This pressure wave excites a resonant vibration of the tuning fork thereby generating an electrical signal via the piezoelectric effect. This paper describes a theoretical model of a QEPAS sensor. By deriving analytical solutions for the partial differential equations in the model, we obtain a formula for the piezoelectric current in terms of the optical, mechanical, and electrical parameters of the system. We use the model to calculate the optimal position of the laser beam with respect to the tuning fork and the phase of the piezo- electric current. We also show that a QEPAS transducer with a particular 32.8 kHz tuning fork is 2-3 times as sensitive as one with a 4.25 kHz tuning fork. These simulation results closely match experimental data.
Structural and Chemical Properties of Native Corn Starch Granules

Native corn starch granules were fractionated according to size and apparent density. Individual fractions were characterized by high performance size exclusion chromatography, differential scanning calorimetry, X-ray diffraction, scanning electron microscopy and enzymatic susceptibility. Native starch granules were not homogeneous; they showed differences in solubility, enzymatic susceptibility and crystallinity. The small, less dense granules were more crystalline than the more abundant larger and denser granules. Neither the degree of solubility of each starch fraction in methyl sulfoxide (DMSO), nor its enzymatic susceptibility, was correlated with fraction crystallinity. Starch granules with different sizes or apparent densities had inherent variations in their crystallinity, which influences granule functional properties. The helical nature of amylose and amylopectin may also contribute to the functional complexity and variability observed in the population of normal starch granules.
Effect of Nb on phase transformations and microstructure in high Nb titanium aluminides

Abstract Titanium aluminides are of interest due to their high specific strength and performance up to 750 °C. Research into high-Nb γ-TiAl based titanium aluminides has shown promising improvements in performance by introduction of the σ-Nb2Al phase. However, one current challenge is improving mechanical properties at room and elevated temperatures in order to enable their further implementation. These properties are closely tied with microstructural refinement, and thus phase evolution and microstructural development is the focus of this work. Phase transformation temperatures and stability ranges were determined experimentally through DSC analysis of arc melted alloys, then compared with predictions based upon computational models, and investigated through heat treatment of experimental alloys to develop an ultrafine γ + σ microstructure.
Crustal resistivity structure at 9°50'N on the East Pacific Rise: Results of an electromagnetic survey

[1] We report the first results of an extensive electromagnetic survey of the East Pacific Rise (EPR) at 9°50′N, which used the magnetometric resistivity (MMR) technique to measure the electrical resistivity structure of the seafloor in the vicinity of the spreading center. Ten seafloor magnetometers were deployed in areas of known hydrothermal activity, in axial sites devoid of venting, and further off-axis to a distance of approximately 4 km. Data collected at off-axis sites show higher seafloor resistivities than at axial sites. This response is opposite to that expected from porosity controlled resistivity structure, with a thicker high-porosity extrusive layer 2A off-axis, as required by seismic data. An explanation for the reduced axial resistivities is that the uppermost few hundred meters of crust are much hotter beneath the ridge crest than a few kilometers off-axis, lowering the pore-fluid resistivity.
Decomposition and nitrogen dynamics of surface weed residues in no-tillage agroecosystems under drought conditions: Influence of resource quality on the decomposer community

Decomposition and net N mineralization rates, and microbial and faunal abundances on residues of three weed species were quantified at two Georgia piedmont no-tillage sites (upland and floodplain) during the winter-spring season of a drought year. The three species examined were Amaranthus retroflexus L. (pigweed). Cassia obtusifolia L. (sicklepod), and Sorghum halepense (L.) Persoon (Johnson grass). Cassia and Amaranthus, with higher initial N concentrations and lower C-to-N ratios, had higher rates of decomposition and net N mineralization, and supported greater populations of bacteria, fungi and nematodes than Sorghum. Lower abundances of fungi and higher numbers of fungivore nematodes and prostigmatid mites occurred in litter on the upland site compared to the floodplain. We suggest that grazing by fungivores may have reduced fungal populations at the upland site. Despite these differences, decomposition and N mineralization rates were similar at the two sites for the three species. We estimated that 35% of the weed biomass N (38 kg N ha−1) was mineralized during the 5 month study, indicating that weed residue can act as a N reservoir in no-tillage agroecosystems.
Imaging performance of a terbium-doped fiber optic screen for diagnostic imaging

The resolution of a fiberoptical boule was determined experimentally. A boule is a matrix of scintillating glass fibers arranged parallel to each other and compressed into a thick plate. A 51 mm X 51 mm by 3 mm thick terbium-activated boule was optically coupled to a 1 k X 1 k X 16 bit CCD camera. The image of an edge was used to compute the line spread function, and the modulation transfer function was calculated. After correcting for the MTF of the CCD and optics, the MTF of the fiberoptical plate demonstrated 20% modulation at a spatial resolution of 15 line pairs per millimeter. The x-ray absorption of the 3 mm thick plate was 98% at 70 kV (3.3. mm half value layer). It is shown using simple trigonometry that for a very high resolution detector, x-ray beam divergence (angled photons striking the receptor) at the periphery of the field of view may cause substantial resolution losses. The role that fiberoptical plate technology may play in diagnostic medical imaging is discussed.
Arcus Venosus Dorsalis Pedis: Morphological Considerations for Use in Superficial Palmar Arch Reconstruction

Purpose To report the branching patterns, vessel diameters, and location of the valves in the arcus venosus dorsalis pedis (AVDP) as a graft option for use in superficial palmar arch reconstruction after mutilating hand injuries. Methods We dissected 10 cadaveric feet and measured vessel diameters, recorded number of branches, and located valves within the tibial, middle, and fibular thirds of the system. We used retrograde india ink injection to locate valves. Results The AVDP branching pattern was grossly different from side to side in the 4 cadavers with bilateral feet available. Mean flat diameters were 4.7, 2.9, and 2.1 mm in the tibial, middle, and fibular thirds of the arch, respectively. There was a mean of 1.7 valves (range, 1–4 valves) in the tibial third, 1.5 valves (range 0–4 valves) in the middle third, and 0 valves in the fibular third. There was an average of 3.4 branches off the middle third with a mean branch diameter of 2.1 mm. In 65% of these branches, valves were within 1 cm distal to the main arch. The direction of flow within the middle third was from fibular to tibial. Conclusions Valves were commonly found within the middle and tibial thirds of the AVDP and within branches just distal to bifurcations. By contrast, the fibular third of the AVDP contained no valves. Valvular anatomy suggests that the direction of flow within the middle third was from fibular to tibial direction. Clinical relevance The AVDP is morphologically similar to the palmar arch. When rendering valves within the AVDP incompetent, attention should be paid not just to the main arch itself, but also to branches off the AVDP. The fibular and middle thirds of the AVDP can safely be used for palmar arch reconstruction without blockage of flow owing to valves. The branches off the middle third must be used within a few millimeters of their takeoff to avoid valves.
Structure, Bonding, and Heats of Formation of Silatitanacyclobutanes

The MP2/TZVP geometries and the standard heats of formation at 0 and 298.15 K of 1,2- and 1,3-silatitanacyclobutanes and a number of smaller Ti- and/or Si-containing alkanes are calculated using the G2 model. The G2 procedure was suitably modified to allow for treatment of first-row transition elements and was directly applied to the reference compounds, which were subsequently connected to the two rings via the appropriate homodesmic reactions. The expected accuracy should be on the order of 3 kcal mol-1. Bonding and structural characteristics are discussed in terms of Boys localized orbitals and Bader density analysis.
Mechanisms of muscle gene regulation in the electric organ of Sternopygus macrurus

Summary Animals perform a remarkable diversity of movements through the coordinated mechanical contraction of skeletal muscle. This capacity for a wide range of movements is due to the presence of muscle cells with a very plastic phenotype that display many different biochemical, physiological and morphological properties. What factors influence the maintenance and plasticity of differentiated muscle fibers is a fundamental question in muscle biology. We have exploited the remarkable potential of skeletal muscle cells of the gymnotiform electric fish Sternopygus macrurus to trans-differentiate into electrocytes, the non-contractile electrogenic cells of the electric organ (EO), to investigate the mechanisms that regulate the skeletal muscle phenotype. In S. macrurus , mature electrocytes possess a phenotype that is intermediate between muscle and non-muscle cells. How some genes coding for muscle-specific proteins are downregulated while others are maintained, and novel genes are upregulated, is an intriguing problem in the control of skeletal muscle and EO phenotype. To date, the intracellular and extracellular factors that generate and maintain distinct patterns of gene expression in muscle and EO have not been defined. Expression studies in S. macrurus have started to shed light on the role that transcriptional and post-transcriptional events play in regulating specific muscle protein systems and the muscle phenotype of the EO. In addition, these findings also represent an important step toward identifying mechanisms that affect the maintenance and plasticity of the muscle cell phenotype for the evolution of highly specialized non-contractile tissues.
Optimum Synthesis of Path-Generating Four-Bar Mechanisms

Synthesis of path-generating four-bar mechanisms is considered as an optimization problem under inequality constraints. The penalty function approach is used. The effects of clearances and tolerances in manufacture are considered in order to make sure that the inequality constraints are within the acceptable tolerance during the required motion. Modifications are introduced in the gradient method, and sequential unconstrained minimization techniques are used in the process of minimization. A typical example under various conditions is presented in order to study the effectiveness of the technique.
Reconsideration of age as a contraindication for curative therapy of sickle cell disease.

Approximately 100 000 Americans, primarily African Americans, have sickle cell disease.1 Worldwide, the burden of this disease is much greater with an estimated 300 000 affected infants born.2 A single nucleotide substitution causes the autosomal recessive disease: valine replaces glutamic acid in the sixth position of the β-globin protein. Despite the discovery of the etiology of sickle cell disease more than 60 years ago,3 little progress has been achieved in the treatment or cure of this chronic disease.
REJECTING ROTATIONAL DISTURBANCES ON SMALL DISK DRIVES USING ROTATIONAL ACCELEROMETERS

Abstract Small disk drives are inherently designed for portable applications and thus must be able to reject external shock and vibration. This paper expands on previous efforts at using the signal from a rotational accelerometer to minimize the the effects of these disturbances by dealing with several issues that come up; accelerometer beam resonances, low sample rate of the embedded servo on the disk drive, and widely varying accelerometer gains. The resulting algorithm is both simple and effective, making it practical for in drive use. Experimental data is provided.
A note on fatigue damage assessment by x-ray diffraction techniques for a 304L stainless steel specimen

The progress of fatigue damage in type 304L solution treated stainless steel was studied by surface residual stress measurements and measurements of the formation of martensite, as determined from x-ray diffraction techniques. The specimen was subjected to tension-tension (R=0.1) cycling in air at a maximum stress σmax=422 MPa, which was approximately 160% off the yield stress. The initial longitudinal residual stress distribution was determined for 13 locations along the gage length and found to vary around −80±17 MPa (compression). After several fatigue cycles, the residual stress changes to approximately +115±17 MPa (tension). At about 7% of the life (N/N f =0.07), the variation of the residual stress along the gage length reaches a minimum. With additional cycling, the residual stress first drops, reaching a minimum at approximately 10% of the life (100±8 MPa), then increases to a maximum at between 20 and 40% of the life (125±18MPa), followed by a marked relaxation to a minimum of 90±18 MPa at approximately 65% of the life. The surface martensite content of the sample continuously increases from its initial value of around 0.6%, first slowly up to 10% of the total fatigue life, and more rapidly thereafter to final failure. On the basis of additional measurements of the residual stress and martensite content as a function of depth below the surface, surface layer hardening of austenite and martensite is suggested as the principal reason for the residual stress development.
Incipient motion of gravel in a bottomless arch culvert

Abstract Incipient motion was investigated for four gravel substrate materials in a bottomless arch culvert and a rectangular flume. Different methods for calculating Shields parameter at incipient motion (θ c ) based upon local flow parameters were explored. An incipient motion region for bottomless arch culverts in fully turbulent flow was defined with two bounding curves on Shields diagram. The variation of θ c as a function of relative roughness was examined. Also, a method that utilizes measured flow velocities to determine stable substrate particle diameters for bottomless arched culverts is presented as an alternative to the Shields diagram.
An approach to improving the six-handed technique in oral rehabilitation

An approach was developed to increase efficiency in oral rehabilitation under general anesthesia. An improved three-person team approach was developed to increase efficiency in oral rehabilitation with the patient under general anesthesia. Directvision of the operating field and increased opportunity for anticipation of the sequence of procedures by all members of the dental team are improvements in this approach.
The problem of reinterpretive distortions in group psychotherapy with borderline patients

Group psychotherapy with borderline patients is challenging work. A group in which the core of patients falls within this nosological category is described. The phrase “reinterpretive distortion” is used to characterize an aspect of these patients' communication style which makes their effective treatment quite difficult. Examples of the phenomenon are offered, as is an explanation of the dynamics which give rise to it and the functions it seems to serve. Effective ways to deal with reinterpretive distortions in the group psychotherapy context are suggested.
Reducing gradient imperfections for spiral magnetic resonance spectroscopic imaging.

Spiral k-space magnetic resonance spectroscopic imaging (MRSI) requires high performance from gradient hardware systems. During the readout phase, oscillating gradients are continuously played out, which can cause undesired effects. These effects on the quality of SI data are non-intuitive because of their time-varying nature. In this work we describe the effects of undesirable gradient performance on SI. Measurements of the true readout trajectories were performed and the results were then used in the reconstruction process. The effects of these imperfections resulted in a spatially and spectrally varying amplitude and frequency modulation. The use of the measured trajectories in the reconstruction process yielded an up to 20% increase in signal amplitude recovery. Magn Reson Med 56: 198 –203, 2006. © 2006 Wiley-Liss, Inc.
Self-Portraits: Possible Selves in European-American, Chilean, Japanese and Japanese-American Cultural Contexts

Possible selves of students from European-American (EA), Chilean (CH), Japanese-American (JA), and Japanese (JN) cultural contexts were analyzed, revealing differences in the emphasis given to various content themes. EA possible selves focus on intrapersonal themes (i.e., “fear being dependent”), consistent with cultural emphases on uniqueness and independent development. In JN, JA and CH contexts, career and education themes dominate possible selves, consistent with particularly strong cultural emphasis on professional and academic accomplishments. The cultural contexts also differ in their predominant configurations of possible selves—EA and CH possible selves often show balance (expected and feared selves of similar theme but opposing valence, i.e., “expect to graduate from college” and “fear dropping out of college”) while JN and JA selves more frequently match (expected and feared selves of similar thematic content and valence, i.e., “expect to be idle” and “fear being idle”).
RECENT RESULTS FROM THE CERN NA44 EXPERIMENT

Recent results for two boson interferometry from CERN experiment NA44 are presented. Experiment NA44 is a focussing spectrometer with both excellent momentum resolution and particle identification. The most recent results shown will be two-pion and two-kaon correlations from 158 GeV/nucleon Pb+Pb running. The systematics of the NA44 two-boson results are described rather well by a final-state rescattering model.
Uncoating of Mature HIV Capsids Driven by Reverse Transcription

Until recently it was a common notion that reverse transcription (RTion) in retroviruses, including HIV, takes place within the cytoplasm of the infected cell after uncoating of the mature capsid. However, accumulating evidence suggests that at least some RTion happens inside the capsid, and may be driving the uncoating. In this theoretical study we consider the problem of mature HIV capsid uncoating driven by polymerization of double stranded (ds) viral DNA by the reverse transcriptase (RT). We take into account that millimolar concentrations of NCp7 contained within the capsid drives aggregation of both single stranded (ss) RNA and dsDNA provided the capsid is intact. The NC-aggregated flexible ssRNA genome occupies only about 5% of capsid volume. The NC-aggregated rigid dsDNA genome is expected to form a tightly wound toroid. For a 103-104 base pair (bp) genome length, the size of this toroid is comparable to, or larger than, the capsid cross-section. At that point either the capsid shell, or the toroid must deform, depending on their comparative rigidities. Since the experimental elasticity parameters of the mature HIV capsid are as yet unknown, we consider both scenarios. In the first case, the capsid is expected to break open (uncoat) when its stress reaches a critical value as described by the theory of elasticity. In the second case, the stress generated by the capsid on the growing toroid eventually stalls the RT. In-vivo HIV uncoating by this mechanism thus must correspond to the first case. Importantly, we predict that a significant fraction of viral dsDNA can be polymerized by RT in the presence of NCp7 before uncoating, even for a low stability capsid.