cssi/SciSciGPT-SciSciNet huggingface dataset:
Indicator geostatistical analysis of sand interconnections within a till

At the Fernald Environmental Management Project (FEMP) site in southwestern Ohio, sand and gravel lenses within till provide potential pathways for the flow of contamination into the underlying aquifer. These high-permeability lenses account for 22% of the volume of the till, have a complex arrangement, and are smaller in scale than the site. Even the relatively dense subsurface sampling program at the FEMP site is not adequate to determine facies interconnections with certainty. To delineate probable facies boundaries, a binary indicator random variable was used to represent the presence of high or low-permeability sediment. The 800 available lithologic logs that penetrate the till were coded with the binary system at 2 ft (0.6 m) intervals yielding 15,829 observations. These data were used to compute the declustered mean of indicator values in horizontal intervals, giving an estimate of the proportion of high-permeability sediment in each vertical zone. The areal correlation in specific zones was examined through indicator variograms, which had pronounced anisotropy. Three-dimensional indicator point kriging was used to produce maps of the probability of existence of high-permeability sediment. These maps were used in a preliminary analysis of sand body interconnectedness. Results indicate that portions of sand bodies are interconnected throughmore » the entire interval studied and that the areal extent of vertical interconnection is up to 1,000 ft.« less
Do bacteria in the clouds cause rain

This idea is that The Bug grows on plant surfaces and can be swept into the atmosphere in microscopic dandruff-like magic carpets where special bacterial proteins nucleate free water in the clouds forming ice crystals. The ice crystals once formed from the bacterial nucleation event, then bounce around and multiply, and can eventually fall to earth as snow or rain. The idea that plants and their bacteria might have a role in clouds and then in rainfall formation was presented some 25 years ago from observations in and above Montana wheat fields. It is only recently that the bioprecipitation cycle hypothesis has had some validity from data generated at the tops of our four ski resorts in the Big Sky and Bozeman areas. They are working with scientists on several continents interested in this hypothesis because by choosing the right crops to sustain the bacteria, they might be able to cause additional rain in drought stricken areas of the world.
Otolith elemental signatures reflect residency in coastal water masses

We examined variability in otolith chemistry of wild caught fish in relation to in situ temperature and salinity within the California Current System. Barium, magnesium, and iron from the most recent growth zone in otoliths differentiated pelagic juvenile shortbelly rockfish (Sebastes jordani) residing in water masses with distinct temperature and salinity properties from central and southern California spanning nearly 500 km of coastline. The 3-element signature also discriminated fish that resided in different water masses that were associated with mesoscale cyclonic eddy circulation in the Santa Barbara Channel. Variability in otolith chemistry reflected the spatial patterns of both horizontal gradients and vertical gradients in water mass properties related to circulation. Although we found that the concentrations of particular elements in otoliths were correlated to ambient temperature or salinity, we suggest that these parameters are more useful as an identifying signature of distinct water masses associated with unique otolith signatures rather than as factors directly affecting otolith chemistry. Other factors varying among the water masses or among the fish populations residing in the water masses may also affect otolith chemistry. We discuss how oceanographic phenomena associated with the 1997–1998 El Nino and the persistent, recirculating eddy in the Channel may have affected coastal ocean conditions and variation in otolith chemistry of fish in the study area.
Morphological Consequences of Catalytic Hydrogenation of Polymers in the Bulk

When suitable catalysts are molecularly dispersed in polymers, the polymers can be modified without added solvent. This paper describes studies on the morphology of samples of trans-1,4-polybutadiene and syn-1,2-polybutadiene which have been partially deuterated in the bulk. The development of a peak in the SANS data for the 1,2-polybutadiene suggests the formation of small domains upon deuteration. Possible explanations for this observation, including chemical and physical heterogeneity, are evaluated. Results of SAXS and thermal measurements are also considered. 11 refs., 3 figs., 1 tab.
Statistical Analysis of Fatigue Related Microstructural Parameters for Airframe Aluminum Alloys

This paper presents the results of statistical analysis of the fatigue related microstructural parameters, mainly on constituent particles and pores, in 7050-T7452 aluminum forging materials. The statistical distributions of the particle and pore area data, which were obtained from the metallographic measurements on polished surfaces, were fitted well with three-parameter lognormal functions. Comparative studies were carried out for the particle and pore size distributions between the core and periphery materials, and between the hand and die forging materials. An extreme value theory-based model was investigated to correlate the overall material particle distribution with the fatigue crack-nucleating particle distribution. The results indicated that the particle size is not the only parameter affecting the fatigue process; other parameters, such as grain size and grain orientation, are also important parameters for microstructure-based fatigue modeling. Therefore, orientation image microscopy (OIM) analyses were carried out on pristine 7050 samples, on different planes, to determine the grain orientation distributions. Finally, a preliminary OIM analysis was performed on a fractured sample to measure the misorientation angles between the grains near the crack nucleation and short crack regions. It is expected that the test observations and quantitative microstructural data could help to understand the effects of microstructure on the fatigue process and develop a microstructure-based fatigue modeling.
An Integrated Patch-Clamp Potentiostat With Electrode Compensation

We present the first fully integrated implementation of a patch-clamp measurement system with series-access resistance and parasitic capacitive compensation capability. The system was implemented in a 0.5- mum silicon-on-sapphire process and is capable of recording cell membrane currents up to plusmn20 nA, with an rms noise of 5 pA at 10-kHz bandwidth. The system can compensate for the capacitance and resistance of the electrode, up to 20 pF and up to 70% of the series-access resistance, respectively. The die size is 1150 by 700 mum. The power consumption is 300 muW at 3.3 V. The integrated patch-clamp system will be used to fabricate high-throughput planar patch-clamp systems.
Does investment in home visitors lead to better psychological health for HIV-affected families? Results from a quasi-experimental evaluation in South Africa

Children and families affected by HIV are at considerable risk for psychological distress. Community-based home visiting is a common mechanism for providing basic counseling and other services to HIV-affected families. While programs emphasize home visitor training and compensation as means to promote high-quality service delivery, whether these efforts result in measurable gains in beneficiaries' well-being remains largely unanswered. This study employs a longitudinal quasi-experimental design to explore whether these kinds of investments yield concomitant gains in psychological outcomes among beneficiaries. Baseline and follow-up data were collected over a two-year period from children aged 10-17 at the time of program enrollment and their caregivers, with 80% retention. In this sample of 1487 children and 918 caregivers, the psychological health outcomes of those enrolled in programs with home visitors who receive intensive training, organizational support, and regular compensation (termed "paraprofessional") were compared to those enrolled in programs offering limited home visiting services from lay volunteers. Applying multilevel logistic regression, no measurable improvements were found among paraprofessional enrollees, and three outcomes were significantly worse at follow-up regardless of program model. Children's behavior problems became more prevalent even after adjusting for other factors, increasing from 29% to 35% in girls and from 28% to 43% in boys. Nearly one-quarter of girl and boys reported high levels of depression at follow-up, and this was a significant rise over time for boys. Rates of poor family functioning also significantly worsened over time, rising from 30% to 59%. About one-third of caregivers reported high levels of negative feelings at follow-up, with no improvements observed in the paraprofessional group. Results highlight that children's and caregivers' psychological outcomes may be relatively impervious to change even in paraprofessional home visiting models. Findings underscore the need for programs serving HIV-affected families to add focused evidence-based psychological interventions to supplement traditional home visiting.
The origins and present status of the radio wave controversy in NMR

The origins, history, and present status of the controversy surrounding a quantum description of the NMR signal as being due to radio waves are traced. With the Principle of Relativity and Coulomb's Law as formal starting points and the minimum of mathematics needed for understanding, the derivation of a classical electromagnetic theory of signal reception is first given. The agreement between that classical theory and a recent NMR experiment is then presented, leading to proof that, except for the highest field imaging experiments, there is no significant contribution of radio waves to the sig- nal. Attention is drawn to the very different properties of the near and far energy, momenta, and fields inherent in the derivation. The role of the Correspondence Principle in formulating a quantum description is then emphasized and it is shown that the stand- ard NMR interpretation of Dicke's theory of coherent spontaneous emission—that the latter is responsible for the NMR signal—cannot be correct. Finally, the author speculates on some of the intriguing relationships found in the classical electrodynamics of NMR signal reception and attempts to relate them to a common quantum electrodynamic precept of near field interaction: that the free induction decay voltage present at the terminals of an open-circuit receiving coil is based on an exchange of virtual photons between the nuclei in a sample and the free electrons in a receiving coil. 2009 Crown in the right of Canada. Concepts Magn Reson Part A 34A: 193-216, 2009.
Spectroelectrochemical studies of E.E. and E.E.C. mechanisms

Summary The absorbance-time characteristics at optically transparent electrodes for e.e. mechanism (1) and (2): A → A ± ˙ ± e − ( 1 ) A ± ˙ → A 2 ± ± e − ( 2 ) and for e.e.c. (1), (2) and (3) A 2 ± → k 1 products ( 3 ) were computer calculated and experimentally tested where A ± ˙ is optically monitored and the rates of reactions (1) and (2) are diffusion limited. For the e.e. case, the slopes of the A−√t plots are in a ratio of 1:1.20 for reactions (1):(4) A → A 2 ± ± 2 e − ( 4 ) when A ± ˙ is being optically monitored for a chronoamperometric experiment and when Keq>103 and kf is fast for reaction (5). A 2 ± + A ⇌ k f 2 A ± ˙ ( 5 ) Experimentally, the oxidation of dimethylphenazine and the reductions of methylviologen and anthraquinone in acetonitrile appeared to fulfil conditions of simple e.e. mechanism. For the e.e.c. case, the value of k1 can be calculated from the A-t1/2 characteristics if Keq and kf are known for the reproportionation reaction (5). The reduction and/or oxidation of several aromatic hydrocarbons in acetonitrile appeared to posses absorbance-time characteristics of an e.e.c. mechanism.
Plasmids and saprophytic growth of Rhizobium leguminosarum bv. trifolii W14-2 in soil

Abstract The role of plasmids in the saprophytic growth of Rhizobium is mostly unknown. Plasmid-cured and complemented derivatives of R. leguminosarum bv. trifolii strain W14-2 were used to investigate the role of plasmids in the growth of this strain in sterile soil incubated under favorable moisture and temperature conditions. Strain W14-2 contains four plasmids ( a,b,c,d ). Absence of single plasmids in plasmid-cured derivatives generally did not reduce growth in soil when compared to the wild-type but absence of plasmid a delayed growth. Derivatives were unable to grow in soil when only plasmids a or d were present in cells. When only plasmids b or c were present, growth was delayed and the final population in 7 days was approximately 10% of the wild-type population. When the wild-type was co-inoculated at equal population into soil with derivatives lacking plasmids a , c , or d, the population of the wild-type at 7 days incubation was approximately 10 times larger than those of the derivatives. Elimination of only plasmid b did not reduce the ability of the strain to grow in soil when competing with the wild-type. Plasmids were involved in saprophytic growth of strain W14-2 in soil and may be important to the ecology of Rhizobium .
Controlling impedance at the man/machine interface

Recent work on the dynamics of interactions between humans and machined is reviewed. An experimental apparatus for simulating virtual environments and investigating the man/machine interface is described. Relevant experiments on the mechanical impedance of the human arm are reviewed. Despite active neuromuscular feedback control, the human arm exhibits the impedance of a passive object. Preliminary results of some experiments on the adaptability of human arm impedance are presented. These results indicate limitation in the rapidity of parameter adaptation in humans. >
Modeling Stream Fish Assemblages with Niche Apportionment Models: Patterns, Processes, and Scale Dependence

Understanding patterns in terms of the mechanistic processes that produce them is the essence of ecology. However, many studies merely document nonrandom patterns of species coexistence without providing insight into the structuring mechanisms and their scale dependence. Moreover, few studies address the mechanisms driving functional diversity. The objectives of this study were to document empirical patterns of species coexistence within stream fish assemblages across a broad geographic region, addressing both the functional and taxonomic organization of those assemblages, and to determine whether the structuring mechanisms are scale dependent. We gathered data from a report published by the Texas Parks and Wildlife Department that provided empirical species abundance distributions for 62 assemblages from 7 ecoregions and 18 river basins. For each assemblage, we simulated expected species abundances using five previously published models of niche apportionment. These models generate relative abundances in proportion to niche breadth and are constrained to maintain observed species richness, but they do not include information on species identity. These models included four stochastic variants of a geometric series (dominance preemption, random fraction, broken stick, and dominance decay) in which species abundances relate directly to niche breadth and one model (random assortment) in which abundances are independent of niche partitioning altogether. To assess scale dependence, we repeated the analyses after pooling assemblages by ecoregion, river basin, and the entire state. The patterns of niche apportionment for assemblages pooled according to river basin are more consistent with local assemblages than with assemblages pooled according to ecoregions or the entire state. These results suggest that niche apportionment plays a crucial role in structuring stream fish assemblages and that functional groups divide niche space more evenly than do species.
Myeloperoxidase Polymorphism and Cognitive Decline in Older Adults in the Health, Aging, and Body Composition Study

Myeloperoxidase, an antimicrobial enzyme, produces oxidative free radicals. Rarely found in normal brain tissue, myeloperoxidase has been detected in microglia associated with Alzheimer's disease plaques. The authors examined a G-463A polymorphism in the promoter region of the myeloperoxidase gene (MPO) to determine the relation of MPO variants to cognitive decline over 4 years in a cohort of adults, aged 70-79 years at baseline (1997-1998), recruited from Memphis, Tennessee, and Pittsburgh, Pennsylvania, into the Health, Aging, and Body Composition Study. In this sample, 8% of the participants had the AA, 36.9% the AG, and 55.2% the GG genotype of MPO. The frequency of AA and AG genotypes was higher in Blacks than Whites (11.2% vs. 5.9%, and 44.1 % vs. 32.9%, respectively). Multivariate logistic regression analyses showed that, for participants with the MPO AA genotype, cognitive decline was 1.58 (95% confidence interval: 1.07, 2.35) times more likely than for participants with the AG genotype and 1.96 (95% confidence interval: 1.33, 2.88) times more likely than for those with the GG genotype. Interactions between MPO and race, sex, or the apolipoprotein gene were not significant. In this sample, MPO AA, associated with decreased production of myeloperoxidase, was found to be a risk factor for cognitive decline.
The correlation between GPA and percent effort on the Guaranteed 4.0 Plan

Beginning with spring 2005, the academic scholarship students in three programs have been introduced to the Guaranteed 4.0 Plan designed by Donna O. Johnson. The students are given specific assignments on the 4.0 Plan to encourage them to organize their time and to use it more effectively. The academic performance of the two freshman NACME scholars cohorts to use the 4.0 Plan was strikingly better than the first semester GPAs for the first two freshman NACME classes which did not have the 4.0 Plan. A student's success depends on their renewed commitment each semester to an effective use of their time. In this paper the semester GPA of the students is correlated with their self-reported percent of the 4.0 Plan that they used that semester. A better understanding of these relationships should be helpful to students when they plan their semester with the goal of doing well academically.
Unconventional wisdom in multicore computing

The aim of this panel is to assess the prevailing assumptions in today's multicore software R&D and computing education, and ask in particular whether the parallel computing community's current trajectory will produce the “right” algorithmic and software infrastructure for tomorrow's applications.
Sol Sherry Lecture in Thrombosis : research on clot stabilization provides clues for improving thrombolytic therapies.

This article is a summary of the Sol Sherry Lecture of the Council on Arteriosclerosis, Thrombosis, and Vascular Biology, which was presented at the 71st Scientific Sessions of the American Heart Association in November 1998.1 It highlights the work from our laboratory, designed to dissect the intricate reactions and molecular control mechanisms that operate in the final stages of the coagulation cascade. This research brought forth the idea that, by selectively blocking the maturation and accretion of thrombi, we should be able to achieve a much safer and more efficient thrombolysis at lower dosages of clot dissolving agents than currently in use. Fibrin is the fundamental building block of the clot matrix. Network formation occurs in an orderly sequence, well separated in time into distinct phases during the course of coagulation of normal plasma. After the reaction of thrombin with fibrinogen, a protofibrillar lattice is formed, with fibrin units lined up in a half-staggered array, reminiscent of laying bricks without mortar (Figure 1⇓, top panel). Lateral bundling into filaments and fibers with concomitant entanglements and branching generates a 3D gel, the appearance of which is a measure of “clotting time.” Then, under the influence of the activated fibrin stabilizing factor (factor XIIIa), covalent bonds are introduced into the structure that causes an irreversible, end-to-end fusion of the fibrin particles (Figure 1⇓, middle panel). Finally, full maturation of the network is brought about by forming covalent bonds between the protofibrils and filaments (Figure 1⇓, bottom panel). Clots displaying the features shown in the top panel of Figure 1⇓ can be readily dissociated into monomeric fibrin in 5 mol/L urea2 3 and on removal of urea, the gel reforms. The equilibrium between the monomeric or low oligomeric forms of soluble fibrin and clotted …
A theory for ice-till interactions and sediment entrainment beneath glaciers

and frozen onto or melted from the glacier base can achieve a steady state that is in balance with the rate that latent heat is transported to or from the basal interface. At constant N, when a gradual increase in heat flow from the glacier base causes the rate of melting to decrease, h increases and continues to do so when the heat flow is great enough to produce freezing. As freezing becomes more rapid and h increases further, the rate of fluid supply to the glacier base reaches a maximum when the effective permeability is sufficiently reduced by the partial ice saturation in the fringe. Larger h can be achieved with slower freezing at the glacier base, but steady states with larger h are unstable. The maximum rate of fluid supply to the glacier base is greater at lower N, higher temperature gradients, and for sediments with higher permeabilities. Unsteady behavior can lead to large changes in h when there is a mismatch between the rate that latent heat can be extracted and the rate that fluid is supplied to the glacier base. Transient behavior driven by abrupt changes in N is characterized by rapid variations in freezing rate, followed by slower adjustments to h that are limited by the timescale for the conduction of latent heat. The resulting patterns of sediment deformation are expected to commonly be distributed over finite depth ranges even when shear is perfectly localized at any single instant in time.
CHANGE IN SURFACE EXTENSIBILITY OF FUNDULUS DEEP CELLS DURING EARLY DEVELOPMENT

SUMMARY The extensibility of the periphery of the deep cells of the Fundulus blastoderm was investigated by applying negative pressure to the cell surface in culture by means of a micropipette. The relative negative pressure required to produce standard deformations of the surface was measured for cells from embryos in 2 different stages of development. Less negative pressure was required to deform cells from early gastrulae than cells from early blastulae. This finding correlates with the behaviour of deep cells in vivo: early blastula cells are rounded, form blebs, and do not engage in locomotion, whereas early gastrula cells form extended lobopodia and lamellipodia and engage actively in locomotion.
A phase II study of YM155 administered as 168 hour continuous infusion in stage IV and unresectable stage III melanoma.

A151 Background Survivin is a member of the inhibitor of apoptosis family of proteins (IAPs) which is responsible for preservation of cell viability and regulation of mitosis in tumor cells. Robust antiproliferative and pro-apoptotic activity was demonstrated in preclinical models of melanoma by YM155, a small molecule survivin suppressant. Phase I/II data indicate good tolerability and the ability to induce responses in various tumors including melanoma, hormone-refractory prostate cancer, NSCLC, and chemotherapy refractory NHL. Methods Thirty-three chemotherapy-naive and one previously treated patients with stage IV (n=30) and unresectable stage III (n=4) melanoma were enrolled in this Phase II open-label study of 7-day (168 hr) continuous infusion of YM155 in 3-week cycles at a dose of 4.8 mg/m2/day. The primary endpoint was response ( RECIST), while secondary endpoints consisted of response duration, overall survival, progression-free survival, and toxicity. Results Thirty-four patients are evaluable and completed a median of 2 cycles of YM155 (range 0-15, 2 patients received 6 cycles in 20.6% of patients). Mean patient age was 60.4 years (range 29-90), with male/female ratio of 23/11 and ECOG PS of 0 (n=27) or 1 (n=7). Evaluation for best overall response showed 1 CR achieved at cycle 2 and confirmed at cycle 4, 1 PR (45% reduction) at cycle 8, 11 SD and 21 disease progression. Responses were observed in soft tissue nodes (3 lesions) and lung nodule (1 lesion) and were maintained for 6 cycles (CR) and 9+ cycles (PR). The median duration of SD is 112 days. The overall response rate is 5.9%, based on investigator assessment, with a median response duration of 157 days, and a mean time to response of 106 days. After a median follow-up of patients of approximately 9 months, 6 deaths were recorded and the median survival is 274 days, with a median PFS of 41 days (mean 114 days). Follow-up for survival is ongoing. Treatment with YM155 was discontinued for objective (n=24) or subjective (n=1) disease progression, fatigue (n=1), and protocol deviation (n=1). Most commonly reported side effects were fatigue (58.8%), nausea (47.1%), pyrexia (23.5%), headache (23.5%), and arthralgia (20.6%). Four grade 3 events consisting of sepsis (n=1) and increased liver function tests (n=3) were considered to be related to YM-155. Conclusions Single-agent YM155 demonstrates promising activity in first-line treatment of metastatic melanoma as demonstrated by objective responses and disease stabilization. Further studies of the efficacy and safety of YM155 in combination with other agents are under evaluation.
MG's 'Baby with the Bath Water'

One important lesson from the Metallgesellschaft hedge loss is easily missed: the intellectual risk of having a hedging strategy understood by the hedge team alone.
Characterization of the ePix10k camera at SSRL and LCLS

The ePix10k x-ray camera is under development at SLAC for use in hard x-ray experiments at the Linac Coherent Light Source (LCLS). It is a lower-noise, higher-maximum-signal autoranging replacement for the Cornell-SLAC Pixel Array Detector in wide-dynamic-range applications. A series of measurements to characterize a prototype system has been carried out at the Stanford Synchrotron Radiation Lightsource and LCLS. Results are presented here.
The role of elasticity in simulating long-term tectonic extension

Author Posting. © Oxford University Press, 2016. This article is posted here by permission of Oxford University Press for personal use, not for redistribution. The definitive version was published in Geophysical Journal International 205 (2016): 728-743, doi:10.1093/gji/ggw044.
Magnetic Polyolefin-based Nanocomposites

Magnetic polyolefin-based nanocomposites were fabricated through a facile one-pot thermal decomposition of organo-metallic precursor, i.e. Fe(CO)5 in polymer-solvent solution condition. The whole fabrication includes dissolution of polyolefin-based hosting matrix in refluxing organic solvent followed by the injection of metallic precursor to perform the in-situ thermal decomposition step. The particle sizes, morphology and dispersion quality of these in-situ synthesized magnetic nanoparticles were investigated by transmission electron microscopy (TEM). Room temperature mossbauer spectrum analysis was used to determine the species of these magnetic nanoparticles. Room temperature magnetic property investigation was utilized to further reveal the magnetic behaviors of these nanocomposites by specifying the saturation magnetization and coercive forces. Thermal gravimetric analysis (TGA) was used to determine the thermal stability of these as-prepared nanocomposites and the particle loadings. The formation mechanisms of these magnetic particles were proposed from the evidence of TEM observations and detailed evolutions are detailed as well.
Sulfation-Hematoxylin-Azure B as an Alternative to Periodic Acid-Schiff Staining

Gentle sulfation of formalin-fixed tissue sections followed by staining in a hematoxylin-azure B sequence results in bright blue staining of tissue elements that stain with the periodic acid-Schiff reaction—especially basement membranes. The stain is relatively rapid, simple, and permanent, is performed with inexpensive, readily available laboratory reagents, and is presented asan alternative to periodic acid-Schiff staining.
22 Reducing the Impact of Psychological Factors on Outcome

Total knee replacement (TKR) is often described as one of the most painful orthopedic recoveries, requiring patients to sequester their fears, push through pain, and dedicate, for some probably the first time in their lives, to an aggressive and regular exercise regime. Patients bring to their surgeries complicated emotions and psychosocial issues; in order to help their patients successfully recover, surgeons and their teams must figure out, with little knowledge of the exact issues and limited expertise in psychology, how to motivate patients so that these issues do not sabotage recovery. This chapter explores the association between a variety of psychological factors and outcome and proposes a practical, easy-to-implement strategy to mitigate the impact of these issues on patients’ recovery.
U.S. Tax Reforms and Their Effects on Average Tax Rates

Tax reforms over the past twenty-five years in the United States have dramatically altered the income tax system with numerous changes in base definitions and tax rates. With all of the changes that have taken place, including the most recent tax cuts in 2001 and 2003, interest in the effect of tax reforms on the distribution of the tax burden is at an all time high. This paper addresses the question by examining average tax rates (ATRs) over time at various points of the income distribution to see how tax reforms have had an impact in this measure of tax burden. To do so meaningfully, however, requires ATRs computed using a consistent measure of income developed by the IRS - the retrospective income concept. In this paper I review the reform efforts starting with the Economic Recovery Act of 1981 (ERTA81), reaching a high water mark with the Tax Reform Act of 1986 (TRA86), and continuing through the Jobs and Growth Tax Relief Reconciliation Act of 2003 (JGTRRA03). After review of these tax acts and their main features, simple time series models are estimated to examine the effects of the acts on average tax rates at various points of the income distribution. In each case, two models are estimated with a simple trend model and a model that includes a set of tax reform regime variables for the seven tax reforms since 1981. The paper concludes with a summary of the evidence on the effects of these tax reform acts on the distribution of ATRs across the income distribution.
Study on Prevalence and Influencing Factors of Internet Addiction in High School Students

Objective To study the prevalence and the influencing factors of internet addiction disorder(IAD) in high school students,and to provide the scientific evidence for IAD prevention and intervention. Methods With stratified random cluster sampling,1,833 high school students were selected from 7 schools in Nanping,and they were investigated with an anonymous questionnaire. Results The total prevalence rate of IAD was 12.1%,and the prevalence rate of male(16.8%) was higher than that of female(7.1%). The prevalence rate of vocational senior schools ranked the first,followed by ordinary schools and key high schools.The risk factors of IAD included playing games online,physical fighting,loneliness,smoking,suicidal attention and the idea of going away from home,while good academic performance was the protective factor. Conclusions There is relatively high prevalence of IAD in high schools of Nanping,and effective measures of prevention and intervention should be taken for the students.
A comparison of cryogel scaffolds to identify an appropriate structure for promoting bone regeneration

To create an ideal graft substitute for regenerating bone, the scaffold should possess osteoconductive, osteoinductive, and osteogenic properties. Hydrogels are a very common scaffold, but the mechanical integrity and nanoporous structure are not advantageous for bone regeneration. Cryogelation is a technique in which the controlled freezing and thawing of a polymer creates a spongy, macroporous structure with ideal structural characteristics and promising mechanical stability. Hydrogels and cryogels of three different materials (chitosan–gelatin, N-vinyl-2-pyrrolidone, and silk fibroin (SF)) were compared to assess the optimal material and form of scaffold for this application. Cryogel and hydrogel structures were tested in parallel to evaluate porosity, swelling, mechanical integrity, cellular infiltration, and mineralization potential. Cryogels proved superior to hydrogels based on swelling potential and mechanical properties. Among the cryogels, SF demonstrated high pore diameter and area, mineralization upon cellular infiltration, and the largest presence of osteocalcin, a marker of bone formation. These results demonstrate the practicality of cryogels for a bone regeneration application and identify SF as a potential material choice.
Using narrow-linewidth lasers for rapidly tunable microwave signal generators

Narrow-linewidth lasers are a key component of photonic microwave signal generators, as the width of the generated RF signal is equal to the beat note of used lasers. Heterogeneous silicon photonics platform opens up a possibility of improving the coherence of fully integrated photonic microwave generators by providing means to separate the photon resonator and absorbing active medium; improving the total Q factor of the laser cavity and providing the control of the spontaneous emission into the lasing mode. Further improvement in the laser linewidth is possible by using ring resonators inside the laser cavity. Using the rings inside the cavity benefits the linewidth in two ways: (1) resonance cavity length enhancement and (2) negative optical feedback. The combined effect allows for record linewidth performance as was recently demonstrated: widely-tunable fully monolithically-integrated semiconductor lasers with 50 kHz integrated linewidths. We further theoretically predict that at least an order of magnitude better performance is achievable and that sub-kHz linewidths should be obtainable using low-loss silicon waveguide platform with ~0.5 dB/cm of loss. Heterogeneous platform further complements the microwave signal generator with demonstrated highspeed modulators with 74 GHz bandwidth and detectors with 12 dBm output power at 40 GHz. The InP-based modified uni-traveling carrier photodiodes on SOI waveguides have the highest reported output power levels at multi-GHz frequencies for any waveguide photodiode technology including native InP, Ge/Si, and heterogeneously integrated photodiodes.
Simultaneous accelerometer measurements of arterial activity during benign ventricular ectopy

Over a 180s observation period, a 3-lead (V5) electrocardiogram (ECG) was collected in a 66 y.o. male subject with benign ventricular ectopy. Simultaneous measures were also made from two tri-axial accelerometers, one placed over the sternum and the other on the forehead. The experiment was repeated with the sensors placed over the femoral and carotid arteries. Signals were sampled at 1kHz and filtered. Ensemble averages (with ±S.D.) and raster plots were generated for each filtered time series from 200 ms before to 800 ms after the peak of each R-wave. Lag times between the R-wave peak (taken as t=0) and the prominent peaks (or valleys) of the various accelerometer signals were calculated, Pulse Transit Times (PTT) determined, and Pulse Wave Velocities (PWV) calculated, given the measured distance between each sensor placement. R-R intervals were calculated between each beat pair and sorted by shortest to longest duration. Ensemble averages and PWV calculations were then repeated by separating sinus rhythm interval pairs, and short and long R-R intervals pairs. The peak acceleration values seen in these three sets of ensemble averages were then compared to determine how normal, short and long R-R intervals influenced external pulse pressure measures.
Precision laser machining–a technology reinvestment project

Laser machine tools today use either carbon diode gas lasers or lamp-pumped solid state lasers, both of which have major limitations. Laser machining is currently inhibited by insufficient power density at the workpiece, inadequate average power that limits the processing speed, high maintenance requirements, and in mally cases nonoptimal beam delivery systems. Recent ARPA iimded developments in diode pllmped solid state lasers and related technology to produce high brightness beams (to enhance focusability makes it possible to break through these processing limitations.
N-acetylglucosamine sensing by a GCN5-related N-acetyltransferase induces transcription via chromatin histone acetylation in fungi

N-acetylglucosamine (GlcNAc) exists ubiquitously as a component of the surface on a wide range of cells, from bacteria to humans. Many fungi are able to utilize environmental GlcNAc to support growth and induce cellular development, a property important for their survival in various host niches. However, how the GlcNAc signal is sensed and subsequently transduced is largely unknown. Here, we identify a gene that is essential for GlcNAc signalling (NGS1) in Candida albicans, a commensal and pathogenic yeast of humans. Ngs1 can bind GlcNAc through the N-terminal β-N-acetylglucosaminidase homology domain. This binding activates N-acetyltransferase activity in the C-terminal GCN5-related N-acetyltransferase domain, which is required for GlcNAc-induced promoter histone acetylation and transcription. Ngs1 is targeted to the promoters of GlcNAc-inducible genes constitutively by the transcription factor Rep1. Ngs1 is conserved in diverse fungi that have GlcNAc catabolic genes. Thus, fungi use Ngs1 as a GlcNAc-sensor and transducer for GlcNAc-induced transcription.
Probing the Crystal Structure and Formation Mechanism of Lanthanide-Doped Upconverting Nanocrystals

Lanthanide (Ln)-doped upconverting nanocrystals (UCNCs), such as NaLnF4 (with Ln = lanthanide), constitute an important class of nanoscale materials due to their capacity to convert near-infrared photons into near-ultraviolet or visible light. Although under intense investigation for more than a decade, UCNCs have been relatively underexplored especially regarding their crystal structure and mechanisms of formation in organic media. The former is needed to explain the relationship between atomic scale structure and upconversion (UC) properties of UCNCs (i.e., local symmetry for 4f–4f transition probability, Ln3+ distances for energy migration), while the latter is essential to finely tune the size, morphology, chemical composition, and architecture of well-defined upconverting nanostructures, which constitute the experimental levers to modify the optical properties. In this contribution, we use synchrotron-based diffraction experiments coupled to Rietveld and pair distribution function (PDF) analyses to u...
An empirical game-theoretic analysis of price discovery in prediction markets

In this paper, we employ simulation-based methods to study the role of a market maker in improving price discovery in a prediction market. In our model, traders receive a lagged signal of a ground truth, which is based on real price data from prediction markets on NBA games in the 2014-2015 season. We employ empirical game-theoretic analysis to identify equilibria under different settings of market maker liquidity and spread. We study two settings: one in which traders only enter the market once, and one in which traders have the option to reenter to trade later. We evaluate welfare and the profits accrued by traders, and we characterize the conditions under which the market maker promotes price discovery in both settings.
A Benign Paroxysmal Positional Vertigo Triage Clinic

Purpose The purpose of this study was to evaluate the effectiveness of triaging patients with motion-provoked dizziness into a benign paroxysmal positional vertigo (BPPV) clinic. Method A retrospec...
Mobile network energy efficiency optimization in MIMO multi-cell systems

In this paper, we consider the energy efficiency maximization problem in downlink multi-input multi-output (MIMO) multi-cell systems, where all users suffer from inter-cell interference. To solve this optimization problem with a nonconcave objective function and a complex-valued matrix variable, we extend the recently developed successive pseudo-convex approximation framework and propose a novel iterative algorithm that has the following advantages: 1) fast convergence as the structure of the original optimization problem is preserved as much as possible in the approximate problem solved in each iteration, 2) easy implementation as each approximate problem is natural for parallel computation and its solution has a closed-form expression, and 3) guaranteed convergence to a stationary point. The advantages of the proposed algorithm are also illustrated numerically in terms of energy efficiency gains from mobile network infrastructure perspective.
Utility of Phox2b immunohistochemical stain in neural crest tumours and non-neural crest tumours in paediatric patients.

Background This study evaluated the utility of Phox2b in pediatric tumors. Previously tyrosine hydroxylase (TH) was the most widely utilized sympathoadrenal marker specific for neural crest tumors with neuronal/neuroendocrine differentiation. However, its sensitivity is insufficient. Recently Phox2b has emerged as another specific marker for this entity. Methods Phox2b IHC was performed on 159 pediatric tumors including (1) 65 neural crest tumors with neuronal differentiation [peripheral neuroblastic tumors (pNT)]: 15 neuroblastoma undifferentiated (NB-UD), 10 NB poorly differentiated (NB-PD), 10 NB differentiating (NB-D), 10 ganglioneuroblastoma intermixed (GNBi), 10 GNB nodular (GNBn), and 10 ganglioneuroma (GN); (2) 23 neural crest tumors with neuroendocrine differentiation [pheochromocytoma/paraganglioma (PCC/PG)]; (3) 27 other neural crest tumors including one composite rhabdomyosarcoma/neuroblastoma; and (4) 44 non-neural crest tumors. TH IHC was performed on group (1), (2) and (3). Results Phox2b was diffusely expressed in pNT (n=65/65): strongly in NB-UD and NB-PD, and in NB-D, GNB and GN with less intensity. Diffuse TH was seen in all NB-PD, NB-D, GNB and GN, but 9/15 NB-UD and a nodule in GNBn didn't express TH (n=55/65). PCC/PG expressed diffuse Phox2b (n=23/23) and diffuse TH except for one tumor (n=22/23). In composite rhabdomyosarcoma, TH was expressed only in neuroblastic cells and Phox2b was diffusely positive in neuroblastic cells and focally in rhabdomyosarcoma. All other tumors were negative for Phox2b (n=0/44). Conclusion Phox2b was a specific and sensitive marker for pNT and PCC/PG, especially useful for identifying NB-UD often lacked TH. Our study also presented a composite rhabdomyosarcoma/neuroblastoma of neural-crest origin. This article is protected by copyright. All rights reserved.
Self-control and the police code of silence: Examining the unwillingness to report fellow officers' misbehavior among a multi-agency sample of police recruits

Abstract Purpose Research has established that low self-control is significantly related to harmful police behavior, but no study, of which we are aware, has investigated the relationship between self-control and adherence to the police code of silence. Methods Structural equation modeling is used to test the theoretical causal sequence linking self-control to the unwillingness to report fellow officers' misbehavior among a multi-agency sample of 1072 police recruits, while controlling for other factors associated with misconduct. Results Though our data specify some support for the general theory of crime, the results suggest that attempting to explain adherence to the code of silence is a complex and multifaceted endeavor. Impulsivity/temper was the only self-control variable, of three tested, to demonstrate a significant effect. Moreover, several other variables, including job satisfaction and cynicism, also significantly predicted the outcome of interest. Conclusions Self-control was found to be a multidimensional construct, and only the impulsivity/temper element was related to police recruits' unwillingness to report fellow officers' misconduct. Notably, though, other factors were also significant in predicting code adherence. This study offers insight into this important phenomenon and our findings yield important policy implications for police administrators.
Characterization and Stability of Trypanosoma cruzi 24-C4 (Tc24-C4), a Candidate Antigen for a Therapeutic Vaccine Against Chagas Disease

Abstract Chagas disease due to chronic infection with Trypanosoma cruzi is a neglected cause of heart disease, affecting approximately 6-10 million individuals in Latin America and elsewhere. T. cruzi Tc24, a calcium-binding protein in the flagellar pocket of the parasite, is a candidate antigen for an injectable therapeutic vaccine as an alternative or a complement to chemotherapy. Previously, we reported that a genetically engineered construct from which all cysteine residues had been eliminated (Tc24-C4) yields a recombinant protein with reduced aggregation and improved analytical purity in comparison to the wild-type form, without compromising antigenicity and immunogenicity. We now report that the established process for producing Escherichia coli –expressed Tc24-C4 protein is robust and reproducibly yields protein lots with consistent analytical characteristics, freeze-thaw, accelerated, and long-term stability profiles. The data indicate that, like most proteins, Tc24-C4 should be stable at −80°C, but also at 4°C and room temperature for at least 30 days, and up to 7-15 days at 37°C. Thus, the production process for recombinant Tc24-C4 is suitable for Current Good Manufacturing Practice production and clinical testing, based on process robustness, analytical characteristics, and stability profile.
Profitable Small Business Strategies under Different Types of Competition

This study empirically examines the profit impact of different strategies under four different types of competition: 1. Low-intensity price and promotion competition; 2. Price competition; 3. Promotion competition; and 4. High-intensity price and promotion competition. The study finds that broad product scope is a key determinant of a firm's profitability in low-intensity price and promotion competition, price competition, and high-intensity price and promotion competition. However, under promotion competition, quality-image orientation was the most profitable strategy.
Algorithms for asynchronous coded caching

The original formulation of the coded caching problem assumes that the file requests from the users are synchronized, i.e., they arrive at the server at the same time. Several subsequent contributions work under the same assumption. Furthermore, the majority of prior work does not consider a scenario where users have deadlines. In our previous work we formulated the asynchronous coded caching problem where user requests arrive at different times. Furthermore, the users have specified deadlines. We proposed a linear program for obtaining its optimal solution. However, the size of the LP (number of constraints and variables) grows rather quickly with the number of users and cache sizes. In this work, we explore a dual decomposition based approach for solving the LP under consideration. We demonstrate that the dual function can be evaluated by equivalently solving a number of minimum cost network flow algorithms. Minimum cost network flow algorithms have been the subject of much investigation and current solvers routinely solve instances with millions of nodes in minutes. Our proposed approach leverages these fast solvers and allows us to solve several large scale instances of the asynchronous coded caching problem with manageable time and memory complexity.