cssi/SciSciGPT-SciSciNet huggingface dataset:
Urine Concentration and Pyuria for Identifying UTI in Infants

BACKGROUND: Varying urine white blood cell (WBC) thresholds have been recommended for the presumptive diagnosis of urinary tract infection (UTI) among young infants. These thresholds have not been studied with newer automated urinalysis systems that analyze uncentrifuged urine that might be influenced by urine concentration. Our objective was to determine the optimal urine WBC threshold for UTI in young infants by using an automated urinalysis system, stratified by urine concentration. METHODS: Retrospective cross-sectional study of infants aged RESULTS: Two-thousand seven hundred infants with a median age of 1.7 months were studied. UTI prevalence was 7.8%. Optimal WBC cut-points were 3 WBC/high-power field (HPF) in dilute urine (likelihood ratio positive [LR+] 9.9, likelihood ratio negative [LR‒] 0.15) and 6 WBC/HPF (LR+ 10.1, LR‒ 0.17) in concentrated urine. For dipstick analysis, positive LE has excellent test characteristics regardless of urine concentration (LR+ 22.1, LR‒ 0.12 in dilute urine; LR+ 31.6, LR‒ 0.22 in concentrated urine). CONCLUSIONS: Urine concentration should be incorporated into the interpretation of automated microscopic urinalysis in young infants. Pyuria thresholds of 3 WBC/HPF in dilute urine and 6 WBC/HPF in concentrated urine are recommended for the presumptive diagnosis of UTI. Without correction of specific gravity, positive LE by automated dipstick is a reliably strong indicator of UTI.
Spike coded bit sequence generation using photonic excitable laser

Excitable laser dynamics is proposed to realize spike coded bit sequence generation. Numerical simulation based on integrated two-section excitable laser and experimental investigation using graphene excitable fiber laser are both demonstrated.
Review: Designing Pan-America: U.S. Architectural Visions for the Western Hemisphere by Robert Alexander Gonzalez

Robert Alexander Gonzalez. Designing Pan-America: U.S. Architectural Visions for the Western Hemisphere . Austin: University of Texas Press, 2011, 280 pp., 204 color and b/w illus. $65, ISBN 9780292723252 The notion of a unified, politically integrated, Western hemisphere, removed from the corruptions and agitations of the Old World, has haunted the American imagination since the early nineteenth century. Simultaneously an idealistic dream, a diplomatic tool, an ideological vehicle, and an economic engine, the Pan-American idea has, along with many other constructs, endured cyclical phases and weathered stale interpretations, waxing and waning along with the policy needs of its dominant enforcer, the United States. Occasionally a subject for historians of politics, international relations, and cultural diplomacy, it has served historians of art and architecture only rarely. Robert Alexander Gonzalez addresses this deficit by exploring what this protean notion has meant for architects and designers over the last 125 years. In four long chapters he moves through a quartet of case studies to invoke an array of practitioners, promoters, politicians, and businessmen, some of them almost entirely forgotten today, who sought to objectify Pan-Americanism for a larger public. The course of this odyssey uncovers a set of evolving visual conventions and familiar cliches, alongside some heterodox challenges that, all together, say something about the continuing contradictions hovering around this intercontinental “contract.” Gonzalez begins by considering what he calls “The Birth of Pan-American Architecture” at several of those …
Narratives of harmful clinical supervision: Introduction to the Special Issue

ABSTRACTDespite the ethical mandate “do no harm,” harmful clinical supervision seems to be occurring internationally among mental health disciplines at an alarming rate. Harmful supervision appears to be largely unacknowledged, unrecognized, and not understood, especially from the supervisees’ perspective. This Special Issue presents 11 anonymous narratives written by supervisees across four mental health disciplines and four continents, plus three reaction articles from supervision experts. The introduction article delineates the rationale for and procedures utilized in obtaining the narratives. The closing article synthesizes the Special Issue contributions, offering conclusions, implications, and recommendations to address harmful supervision systemically across disciplines and internationally.
Log Odds and the Interpretation of Logit Models.

Objective We discuss how to interpret coefficients from logit models, focusing on the importance of the standard deviation (σ) of the error term to that interpretation. Study Design We show how odds ratios are computed, how they depend on the standard deviation (σ) of the error term, and their sensitivity to different model specifications. We also discuss alternatives to odds ratios. Principal Findings There is no single odds ratio; instead, any estimated odds ratio is conditional on the data and the model specification. Odds ratios should not be compared across different studies using different samples from different populations. Nor should they be compared across models with different sets of explanatory variables. Conclusions To communicate information regarding the effect of explanatory variables on binary {0,1} dependent variables, average marginal effects are generally preferable to odds ratios, unless the data are from a case–control study.
A locally conservative stabilized continuous Galerkin finite element method for two-phase flow in poroelastic subsurfaces

Abstract We study the application of a stabilized continuous Galerkin finite element method (CGFEM) in the simulation of multiphase flow in poroelastic subsurfaces. The system involves a nonlinear coupling between the fluid pressure, subsurface's deformation, and the fluid phase saturation, and as such, we represent this coupling through an iterative procedure. Spatial discretization of the poroelastic system employs the standard linear finite element in combination with a numerical diffusion term to maintain stability of the algebraic system. Furthermore, direct calculation of the normal velocities from pressure and deformation does not entail a locally conservative field. To alleviate this drawback, we propose an element based post-processing technique through which local conservation can be established. The performance of the method is validated through several examples illustrating the convergence of the method, the effectivity of the stabilization term, and the ability to achieve locally conservative normal velocities. Finally, the efficacy of the method is demonstrated through simulations of realistic multiphase flow in poroelastic subsurfaces.
Imaging of the Clavicle

Radiography is the initial modality for imaging of the clavicle in most instances, and accordingly, the projections necessary to optimize visualization of the clavicle, acromioclavicular joint, and sternoclavicular joint are described and discussed. Recent developments in computed tomography (CT) allow for enhanced osseous rendering and more accurate visualization of hardware failure and related complications to clavicular fractures. However, it is important to recognize that magnetic resonance imaging (MRI) has extended the feasibility of prescribing advanced imaging to aid in perioperative planning and post-operative assessment by its superior soft tissue contrast and direct multi-planar imaging capability. Refinements and new sequences in MRI achieve finer delineation of the soft tissues, cartilage and bone; specifically, these may offer insights into the assessment of tissue quality and integrity following injury to the sternoclavicular or acromioclavicular joints as well as complex reconstructions. Finally, the procedural use of ultrasound to guide injections of the acromioclavicular and sternoclavicular joints for either diagnostic or therapeutic injections is also practically described.
Cerebral blood flow in normal aging adults: cardiovascular determinants, clinical implications, and aerobic fitness.

Senescence is a leading cause of mortality, disability, and non-communicable chronic diseases in older adults. Mounting evidence indicates that the presence of cardiovascular disease and risk factors elevates the incidence of both vascular cognitive impairment and Alzheimer's disease (AD). Age-related declines in cardiovascular function may impair cerebral blood flow (CBF) regulation, leading to the disruption of neuronal micro-environmental homeostasis. The brain is the most metabolically active organ with limited intracellular energy storage and critically depends on CBF to sustain neuronal metabolism. In patients with AD, cerebral hypoperfusion, increased CBF pulsatility, and impaired blood pressure control during orthostatic stress have been reported, indicating exaggerated, age-related decline in both cerebro- and cardiovascular function. Currently, AD lacks effective treatments; therefore, development of preventive strategy is urgently needed. Regular aerobic exercise improves cardiovascular function, which in turn may lead to a better CBF regulation, thus reducing the dementia risk. In this review, we discuss the effects of aging on cardiovascular regulation of CBF and provide new insights into the vascular mechanisms of cognitive impairment and potential effects of aerobic exercise training on CBF regulation. This article is protected by copyright. All rights reserved.
Invasive earthworms change nutrient availability and uptake by forest understory plants

Assess whether invasive earthworms alter nutrient dynamics in habitats they colonize. We investigated nutrient dynamics of forest soils and three native plant species (Acer saccharum, Polygonatum pubescens, Polystichum acrostichoides) along four earthworm invasion gradients in central New York. Earthworm biomass (a proxy for earthworm impact) was related to distribution and concentration of soil and plant nutrients. At shallower depths, earthworms were associated with lower total and exchangeable P, but higher Ca, K, Mg and Mn. Earthworm-invaded plots showed higher soil Ca and higher foliar Ca in A. saccharum and P. acrostichoides, and lower soil P with lower foliar P in P. pubescens. Presence of earthworms substantially decreased rooting volume in the A horizon, co-occurring with a build up of exchangeable nutrient concentrations and pools. Overall, earthworm biomass was a better predictor of foliar nutrient concentrations than either exchangeable or total nutrient concentrations and pools. Earthworms may create stressful rooting conditions, limiting rooting of native plants in the A horizon. The resulting plant-accessible nutrient pool that builds up in the A horizon of earthworm-invaded soils could provide a mechanism for the invasive success of non-indigenous plants that have an evolutionary association with earthworms in the native range and that follow earthworm invasions.
Discounting and intragenerational equity

We study the social discount rate, taking into account inequality within generations, that is, across countries or individuals. We show that if inequality decreases over time, the social discount rate should be lower than the one obtained by the standard Ramsey rule under certain but reasonable conditions. Applied to the global discount rate and due to the projected convergence across countries, this implies that the inequality adjusted discount rate should be about twice as high as the standard Ramsey rule predicts. For individual countries on the other hand, where inequality tends to increase over time, the effect goes in the other direction. For the United States for instance, this inequality effect leads to a reduction of the social discount rate by about 0.5 to 1 percentage points. We also present an analytical formula for the social discount rate allowing us to disentangle inequality, risk, and intertemporal fluctuation aversion.
Symmetries and Relativistic Scalar Quantum Fields

Just as for non-relativistic quantum fields, the theory of free relativistic scalar quantum fields starts by taking as phase space an infinite dimensional space of solutions of an equation of motion. Quantization of this phase space proceeds by constructing field operators which provide a representation of the corresponding Heisenberg Lie algebra, using an infinite dimensional version of the Bargmann–Fock construction. In both cases, the equation of motion has a representation-theoretical significance: It is an eigenvalue equation for the Casimir operator of a group of space-time symmetries, picking out an irreducible representation of that group. In the non-relativistic case, the Laplacian \(\Delta \) was the Casimir operator, the symmetry group was the Euclidean group E(3), and one got an irreducible representation for fixed energy.
Discovery of the Physics of Color

Anyone who has shared the company of three-year old children for an afternoon will recognize the conversation. Everything you say is challenged immediately with their favorite word—why? Newly arrived in the world and fascinated by all they see, three-year olds want to know the why of everything. They live in a world of mystery, wonder, and possibility—where magic is real and reality is magic. As we explore the discovery of the physics of color origin and perception, put yourself in the place of the three-year old who always wants to know why. Or put yourself in the place of the discoverers themselves who must have been filled with awe at what they learned and communicated to the world for the first time.
Mental health service use decision-making among young adults at clinical high risk for developing psychosis.

AIM Research has shown that young adults at clinical high risk (CHR) for developing psychosis have the capability to recognize that they have a problem and initiate mental health services, yet there is a paucity of theoretically based research examining this decision-making process. This is critical to study because there are high rates of underutilization of mental health services among these young people. The following study explored the decision-making process among young adults at CHR in order to understand mental health services utilization at a CHR clinic. METHODS Semi-structured face-to-face interviews were conducted with 30 young adults at CHR between the ages of 18 and 30, from an Eastern city in the United States. The study applied the unified theory of behaviour (UTB), a decision-making framework for health behaviour, to examine service use. Content analysis with multiple coders was used. RESULTS The most salient constructs discussed when participants envisioned seeking services at the clinic included attitudes or beliefs about help-seeking, social image beliefs and emotional reactions towards seeking services. Differences in UTB responses emerged depending on whether participants were engaged in clinical services and research at the time of the interview or just taking part in research follow-ups. CONCLUSION When designing future interventions to increase service utilization among young adults at CHR, programs can address health beliefs such as how services at the clinic can improve symptoms, stigma and difficult emotions such as fear and shame about seeking services, and particularly among young people who are more ambivalent about seeking clinical services.
Flow, Rest, Inertial Motion: Wilner, Di Piero, Bonnefoy

Poetry, like music, is an art that is inherently temporal. Just as we must hear a melody in time, so we must read a poem in time. I hum the melody to myself as I recall it, and say the poem over to myself, half out loud. Like a melody, a poem is never all there at once: we must run through it. Yet in many respects time is inimical to discourse: its irresistible, irrevocable flow, the river of time, carries us all away. A poem cannot be merely temporal; to be art and to be remembered—to be memorable art—a poem must resist temporality or make something of it. How do we do that? Our experience, so thoroughly temporal, would be a mere flood too (and so we wouldn’t have any experience at all) unless we could remember events and classify things, and organize the world by telling stories and offering explanations. In the flood of time, we remember backwards in reflection and project forwards in action, using discourse; and we build things that are stable, houses and chairs and books. So our experience is really a side-eddy in the river of time, close to the mossy or stony bank, where past, present and future are held together by awareness. Time circles, impossibly, in that side eddy.
The jurisdictional return on investment from processing the backlog of untested sexual assault kits

Abstract The economic problem for the forensic laboratory is a problem faced in all arenas; limited resources are available to address seemingly unlimited desires. This is as true for entities in the public sector as it is for any private concern. To assist decision-makers in the allocation of those scarce resources, we synthesize existing research on the benefits of additions to the DNA Database and the potential benefits from diverting resources to analysis of the backlog of sexual assault kits. We offer some guidance for the optimum use of limited resources, through the measurement of the return on investment (ROI) at the jurisdictional level (i.e., that is, the net benefits to society relative to the investment itself). These net benefits include those to survivors from a resolution to their assaults, the benefits to others from the prevention of repeated assaults from serial rapists, and the prevention of societal costs external to those directly victimized. Those external costs extend from the effects on friends and family to expenses for preventive measures to anyone aware of sexual assaults. Such metrics surrounding ROI will assist the public sector in the optimal allocation of scarce resources to the justice system by providing a measures of the marginal social welfare improvement from alternative allocations of these scarce resources in light of objectives of public sector entities. The analysis demonstrates that the societal return on investment from the testing of all sexual assault kits ranges from 9,874% to 64,529%, depending on the volume of activity for the laboratory conducting the analysis. There are extreme economies of scale in effect that are suggestive of some policy alternatives.
Principles of Mandibular Reconstruction with Vascularized Flaps

Mandibular reconstruction is often necessary after benign and malignant tumor expiration, traumatic defects, or congenital abnormalities. The goals of mandibular reconstruction are to reestablish mandibular continuity while also allowing for restoration of speech, esthetics, swallowing, and dental rehabilitation.
Locus of semantic generalization of the galvanic skin response and possible inhibitory influence of conditional stimuli upon unconditional response following conditioning with innocuous and noxious unconditional stimuli.

Two different problems were investigated using the GSR index of the orienting reflex (OR): 1) the locus of semantic generalization: and 2) a possible inhibitory influence of the CS upon the UCR. Two experiments were conducted. One experiment employed an innocuous USC, and a second similar experiment used a loud noise as the UCS. Unidirectional word associates were employed in the test of the direction of semantic generalization. Constant and varying CS words were used to test the possible inhibitory influence of the CS upon the UCR. Evidence was obtained of semantic generalization occurring in the training and in the test situation. There was no evidence of the CS developing inhibition over the UCR. Theoretical interpretations of both phenomena were considered. The need for developing theories of conditioning of the OR in humans was emphasized in contrast to current efforts to apply inappropriate cognitive animal learning theories which fail to consider biologic constraints.
Mob Family Proteins: Regulatory Partners in Hippo and Hippo-Like Intracellular Signaling Pathways

Studies in yeast first delineated the function of Mob proteins in kinase pathways that regulate cell division and shape; in multicellular eukaryotes Mobs regulate tissue growth and morphogenesis. In animals, Mobs are adaptors in Hippo signaling, an intracellular signal-transduction pathway that restricts growth, impacting the development and homeostasis of animal organs. Central to Hippo signaling are the Nuclear Dbf2-Related (NDR) kinases, Warts and LATS1 and LATS2, in flies and mammals, respectively. A second Hippo-like signaling pathway has been uncovered in animals, which regulates cell and tissue morphogenesis. Central to this emergent pathway are the NDR kinases, Tricornered, STK38, and STK38L. In Hippo signaling, NDR kinase activation is controlled by three activating interactions with a conserved set of proteins. This review focuses on one co-activator family, the highly conserved, non-catalytic Mps1-binder-related (Mob) proteins. In this context, Mobs are allosteric activators of NDR kinases and adaptors that contribute to assembly of multiprotein NDR kinase activation complexes. In multicellular eukaryotes, the Mob family has expanded relative to model unicellular yeasts; accumulating evidence points to Mob functional diversification. A striking example comes from the most sequence-divergent class of Mobs, which are components of the highly conserved Striatin Interacting Phosphatase and Kinase (STRIPAK) complex, that antagonizes Hippo signaling. Mobs stand out for their potential to modulate the output from Hippo and Hippo-like kinases, through their roles both in activating NDR kinases and in antagonizing upstream Hippo or Hippo-like kinase activity. These opposing Mob functions suggest that they coordinate the relative activities of the Tricornered/STK38/STK38L and Warts/LATS kinases, and thus have potential to assemble nodes for pathway signaling output. We survey the different facets of Mob-dependent regulation of Hippo and Hippo-like signaling and highlight open questions that hinge on unresolved aspects of Mob functions.
A comparison of patient testimonials on YouTube of the most common orthodontic treatment modalities: Braces, in-office aligners, and direct-to-consumer aligners.

INTRODUCTION The aims of this study were to (1) investigate and compare the educational value of the most popular YouTube (www.youtube.com; Google, San Bruno, Calif) orthodontic patient testimonials between braces, in-office aligners (IOA), and direct-to-consumer aligners (DTCA), and (2) classify the emotional response of the viewers through sentiment analysis of the video comments. METHODS Three different phrases relevant to braces, IOA, and DTCA were searched on YouTube. The 20 most popular patient testimonial videos meeting the criteria for each group were selected for a total of 60 videos. Using the YouTube application program interface for each video, 13 video metrics were extracted. An information completeness score was assigned, and the video comments were analyzed using sentiment analysis software. RESULTS The 60 videos included were viewed 34.4 million times by internet users. Braces videos had significantly more likes, comments, and a higher viewer interaction score than the IOA and DTCA videos. IOA videos had a higher median information completeness score than braces and DTCA videos. Of the 5149 video comments with polarity, 53.6% were positive, and 46.4% were negative (P <0.0001). There was no significant association between the treatment modality and positive or negative comments (P = 0.5679). CONCLUSIONS There is high user engagement on YouTube with orthodontic patient testimonials. YouTube users interact with braces patient testimonials the most. YouTube viewers' comments on orthodontic patient testimonials express more positive sentiment than negative sentiment. There was no significant difference in positive and negative sentiment between the video comments for the 3 different treatment modalities.
Systematic review of student anxiety and performance during objective structured clinical examinations.

Abstract Introduction Test anxiety is well studied in higher education, but studies primarily concern traditional assessments, such as written examinations. As use of objective structured clinical examination (OSCE) in pharmacy education increases, a closer examination of non-cognitive factors such as test anxiety is warranted. The purpose of this review was to determine the association between OSCE-associated test anxiety with OSCE performance in health professional students. Methods A literature search was conducted to identify peer-reviewed literature concerning test anxiety in health professional students associated with OSCE. Investigators searched for a combination of OSCE-related terms with anxiety-related terms using PubMed. Articles were included if they assessed OSCE-related anxiety by quantitative or qualitative methods. Data extracted from eligible articles included demographic data, type of the anxiety survey, associations between OSCE-related anxiety and performance, and other student-factors associated with OSCE-related anxiety. Results The literature search yielded 339 articles. Nine articles met eligibility criteria and were included in the review. Results included students from medical, pharmacy, dental, and nursing professional programs. Anxiety was assessed via multiple scales. Six out of the eight studies assessing the relationship OSCE-related anxiety and OSCE performance found no association between the two measures. Contrary to literature concerning test anxiety in higher education, female gender was not associated with OSCE-related anxiety. Conclusion OSCE-related anxiety appears to have minimal to no influence on student performance. Future studies should utilize standardized anxiety assessments and should seek to understand anxiety's effects on student wellbeing and burnout.
Heterozygosity of murine Crkl does not recapitulate behavioral dimensions of human 22q11.2 hemizygosity.

Deletions in 22q11.2 human chromosome are known to be associated with psychiatric disorders, such as intellectual disability, schizophrenia, autism spectrum disorder, and anxiety disorders. This copy number variation includes a 3.0 Mb deletion and a nested proximal 1.5 Mb hemizygous deletion in the same region. Evidence indicates that the distal 22q11.2 region outside the nested 1.5 Mb deletion also might be contributory in humans. However, the precise genetic architecture within the distal region responsible for psychiatric disorders remains unclear, and this issue cannot be experimentally evaluated beyond the correlation in humans. As CRKL (CRK-like Proto-Oncogene, Adaptor Protein) is one of the genes encoded in the distal 22q11.2 segment and its homozygous deletion causes physical phenotypes of 22q11.2 hemizygous deletion, we tested the hypothesis that its murine homolog Crkl contributes to behavioral phenotypes relevant to psychiatric disorders in mice. Congenic Crkl heterozygosity reduced thigmotaxis, an anxiety-related behavior, in an inescapable open field, but had no apparent effect on social interaction, spontaneous alternation in a T-maze, anxiety-like behavior in an elevated plus maze, or motor activity in an open field. Our data indicate that the heterozygosity of murine Crkl does not recapitulate social deficits, working memory deficits, repetitive behavior traits or hyperactivity of human 22q11.2 hemizygous deletion. Moreover, while 22q11.2 hemizygous deletion is associated with high levels of phobia and anxiety in humans, our data suggest that Crkl heterozygosity rather acts as a protective factor for phobia-like behavior in an open field.
Partial, (in)authentic, and masked: an exploration of power in doctoral students’ identity development as scholars through collaborative autoethnography

As three doctoral students, we conducted a collaborative autoethnography to explore how power dynamics in higher education played a role in our identity development as scholars. Through the lens of...
Multimodality and the 5R Instructional Model: Biology Teachers Learning to Engage Emergent Multilingual Learners.

The purpose of this study was to understand how biology teachers experienced and learned from professional development (PD) in which the 5R Instructional Model was used as a framework for planning ...
EXPLOITING EARLY TIME RESPONSE USING THE HALF FOURIER TRANSFORM (HFT)

The singularity expansion method (SEM) proposed by Baum1 has been applied to quantify an electromagnetic response in an expansion of complex resonances of the system2.It has been shown that the dominant complex natural resonances of a system are a minimal set of parameters that define the overall physical properties of the system.3 So, a transient scattering response is analyzed in terms of the damped oscillations corresponding to the complex resonant frequency of the scatterer or target. In general, the signal model of the observed late time of an electromagnetic-energy-scattered response from an object can be written as $$ y(t) = x(t) + n(t) \approx \sum\limits_{m = 1}^M {R_m \exp (s_m t) + n(t);0 \leqslant t \leqslant T,} $$ (1) where y(t) is the observed time domain response, n(t) is the noise in the data, x(t) is the signal, R m is the mth residue or complex amplitude, s s = -αm + jωm, αm is the mth damping factor, and ωm is the mth angular frequencies (ωm = 2πfm).
Portfolio Choice and Equity Characteristics: Characterizing the Hedging Demands

This paper examines portfolio allocation across equity portfolios formed on the basis of characteristics like size and book-to-market. In particular, the paper assesses the impact of return predictability on portfolio choice for a multi-period investor with a coefficient of relative risk aversion of 4. Compared to the investor's allocation in her last period, return predictability with dividend yield causes the investor early in life to tilt her risky-asset portfolio away from high book-to-market stocks and away from small stocks. These results are explained using Merton's (1973) characterization of portfolio allocation by a multiperiod investor in a continuous time setting. Abnormal returns relative to the investor s optimal early-life portfolio are also calculated. These abnormal returns are found to exhibit the same cross-sectional patterns as abnormal returns calculated relative to the market portfolio: higher for small than large firms, and higher for high than low book-to-market firms. Thus, hedging demand may be a partial explanation for the high expected returns documented empirically for small firms and high book-to-market firms. However, even with this hedging demand, the investor wants to short-sell the low book-to market portfolio to hold the high book-to-market portfolio. The utility costs of using a value-weighted equity index or of ignoring predictability are also calculated. An investor using a value-weighted equity index would give up a much larger fraction of her wealth to have access to book-to-market portfolios than size portfolios. Finally, while an investor would give up a much larger fraction of her wealth to have access to dividend yield information than term spread information
Diffusion kinetics of Fe2+ and Mg in aluminous spinel: experimental determination and applications

The diffusion coefficients of Fe2+ and Mg in aluminous spinel at ∼20 kb, 950 to 1325°C, and at 30 kb, 1125°C have been determined via diffusion couple experiments and numerical modeling of the induced diffusion profiles. The oxygen fugacity, fO2, was constrained by graphite encapsulating materials. The retrieved self-diffusion coefficients of Fe2+ and Mg at ∼20 kb, 950 to 1325°C, fit well the Arrhenian relation, D = D0exp(−Q/RT), where Q is the activation energy, with D0(Fe) = 1.8 (±2.8) × 10−5, D0(Mg) = 1.9 (±1.4) × 10−5 cm2/s, Q(Fe) = 198 ± 19, and Q(Mg) = 202 ± 8 kJ/mol. Comparison with the data at 30 kb suggests an activation volume of ∼5 cm3/mol. From analysis of compositional zoning in natural olivine-spinel assemblages in ultramafic rocks, previous reports concluded that D(Fe-Mg) in spinel with Cr/(Cr + Al) ≤0.5 is ∼10 times that in olivine. The diffusion data in spinel and olivine have been applied to the problems of preservation of Mg isotopic inhomogeneity in spinel within the plagioclase–olivine inclusions in Allende meteorite and cooling rates of terrestrial ultramafic rocks.
Organometallic Reaction Mechanisms

Publisher Summary This chapter describes organometallic reaction mechanisms. Considerable progress has been made in establishing the mechanistic pathways by which organornetallic compounds react. The chapter discusses some aspects of this progress, with emphasis on the unique parallel between coordination chemistry and organometallic chemistry. This parallel is demonstrated in (1) ligand exchange reactions, which are equilibrium processes; (2) solvent and salt effects on the path and rate of organometallic reactions; (3) the electrochemistry of organometallics; and (4) in data demonstrating the importance of nucleophilic participation at metal and electrophilic attack at carbon in scission and addition reactions of organometallic compounds. This chapter discusses organometallic derivatives of the nontransition metals and reactions involving scission of an M–H or M–C bond. In the area of organometallic reaction mechanisms, there is considerable room for well-conceived mechanistic studies, particularly, in those cases, where the reagents are extremely difficult to handle and where absolute reaction rate constants are exceedingly high. The nature of the carbon–metal bond in various solvents, and the aggregation of the organometallic reagent in many cases also need re-examination.
The phenotypic signature of adaptation to thermal stress in Escherichia coli.

In the short-term, organisms acclimate to stress through phenotypic plasticity, but in the longer term they adapt to stress genetically. The mutations that accrue during adaptation may contribute to completely novel phenotypes, or they may instead act to restore the phenotype from a stressed to a pre-stress condition. To better understand the influence of evolution on the diversity and direction of phenotypic change, we used Biolog microarrays to assay 94 phenotypes of 115 Escherichia coli clones that had adapted to high temperature (42.2 °C). We also assayed these same phenotypes in the clones’ ancestor under non-stress (37.0 °C) and stress (42.2 °C) conditions. We explored associations between Biolog phenotypes and genotypes, and we also investigated phenotypic differences between clones that have one of two adaptive genetic trajectories: one that is typified by mutations in the RNA polymerase β-subunit (rpoB) and another that is defined by mutations in the rho termination factor. Most (54 %) phenotypic variation was restorative, shifting the phenotype from the acclimated state back toward the unstressed state. Novel phenotypes were more rare, comprising between 5 and 18 % of informative phenotypic variation. Phenotypic variation associated statistically with genetic variation, demonstrating a genetic basis for phenotypic change. Finally, clones with rpoB mutations differed in phenotype from those with rho mutations, largely due to differences in chemical sensitivity. Our results contribute to previous observations showing that a major component of adaptation in microbial evolution experiments is toward restoration to the unstressed state. In addition, we found that a large deletion strongly affected phenotypic variation. Finally, we demonstrated that the two genetic trajectories leading to thermal adaptation encompass different phenotypes.
Top-Down Causation and Autonomy in Complex Systems

Evolutionary evidence shows that complex dynamical systems become increasingly self-directed and decoupled from merely energetic forces over time. In this paper I analyze these transformations, concentrating on changes in the type of top-down causation that characterizes such self-organized and autopoietic pro cesses. Specifically, I show that the top-down selection criteria of these systems makes some of them autonomous, and that because once evolution reaches humans the criteria according to which voluntary actions are selected are semantic and symbolic – and can be self-consciously chosen – human self-direction constitutes a form of strong autonomy that can arguably be considered “free will.”
Asymmetric random walk model for laser induced drift

A theory is presented for laser induced drift based on an asymmetric random walk. The random walk formulation generates an intensity dependent drift velocity, which is valid far from any boundaries.
Wavelet-based solution to anisotropic diffusion equation for edge detection

We consider the problem of detection of edges in an image by solving an anisotropic diffusion equation, which has the intrinsic property that low-contrast regions are smoothed and high-contrast ones are enhanced. Since wavelets are known to provide better representation of singularities (i.e., edges), a more efficient scheme than those suggested earlier for solving the diffusion equation is formulated in terms of wavelet expansions of the image. These expansions also provide a natural way of estimating the local contrast, and hence of implementing a space-varying parameterization of the diffusion equation for improved performance. Our method can be viewed as a wavelet counterpart of standard spectral methods for solving partial differential equations. © 1998 John Wiley & Sons, Inc. Int J Imaging Syst Technol, 9, 356–368, 1998
Contribution of macroporosity to infiltration into a continuous corn no-tilled watershed: Implications for contaminant movement

Abstract Rainfall and runoff were measured for many years on small watersheds on 10–15% slopes in east-central Ohio. Surface runoff from watersheds used for corn ( Zea mays L.) production was high with conventional tillage and very low with no-tillage. A 50-year storm produced 15 times more runoff from a plowed watershed than from a mulch-covered no-till watershed. Reduced runoff from the no-till surface resulted in increased percolation and enhanced the potential for transport of agricultural chemicals to the groundwater. The mulched surface of the no-till watershed also created a favorable environment for the deep burrowing earthworm, Lumbricus terrestris L., whose burrows can transmit water rapidly downward through the soil profile, thus contributing to the high infiltration rates. Open biopores and smaller structural pores were counted and measured to characterize the major flow paths of water movement in the no-till soil. Photos of horizontal surfaces at 2.5-, 7.5-, 15-, and 30 - cm depths and vertical faces of impregnated samples from the 1- and 5-cm depths were evaluated by image analysis. Number of pores was inversely proportional to pore diameter, however pores in the 0.05–1.0-mm diameter range accounted for less porosity than did those in the 1.0–5.0-mm range. The large pores were nearly vertical earthworm burrows and were continuously open from near the surface to the bedrock. Surface applications of lime increased subsoil pH in the no-till watershed but had little effect below the plow sole in the tilled watershed, suggesting that rapid movement of water in large pores can enhance chemical migration into the subsoil.
The Ignorant Led by the Blind: A Hybrid Human---Machine Vision System for Fine-Grained Categorization

We present a visual recognition system for fine-grained visual categorization. The system is composed of a human and a machine working together and combines the complementary strengths of computer vision algorithms and (non-expert) human users. The human users provide two heterogeneous forms of information object part clicks and answers to multiple choice questions. The machine intelligently selects the most informative question to pose to the user in order to identify the object class as quickly as possible. By leveraging computer vision and analyzing the user responses, the overall amount of human effort required, measured in seconds, is minimized. Our formalism shows how to incorporate many different types of computer vision algorithms into a human-in-the-loop framework, including standard multiclass methods, part-based methods, and localized multiclass and attribute methods. We explore our ideas by building a field guide for bird identification. The experimental results demonstrate the strength of combining ignorant humans with poor-sighted machines the hybrid system achieves quick and accurate bird identification on a dataset containing 200 bird species.
Energy-balanced cross layer traffic and coding optimality in battery-powered wireless mesh networks

How to prolong the lifetime of multi-hop-multi-path wireless mesh networks powered by finite battery resource is a critical research challenge. In this paper, we strive for energy-balancing to maximize the network lifetime, while improving multimedia service quality via exploring both hop and path diversities. Different from traditional research, which sacrifices throughput for efficient energy utilization in the networks, we proposed a new approach jointly considering 5 factors in a cross layer fashion: the wireless channel condition, the physical layer channel coding redundancy, the application layer traffic rate, the path level energy-balancing of the network, and the Quality of Service (QoS) of multimedia. In the proposed approach, we develop an optimal scheme to allocate path-level multimedia traffic and link-level channel coding redundancy jointly, which minimizes the routers' battery energy difference while satisfying a lower bound of quality requirement. The simulation results illustrate that the proposed approach can significantly improve the energy-balancing of the multi-hop-multi-path wireless mesh networks by performing the traffic and channel coding control.
Thomson scattering of intense lasers from electron beams at arbitrary interaction angles.

Analysis of nonlinear Thomson scattering of intense lasers from relativistic electron beams is extended to describe off-axis scattering geometries. Electron trajectories are calculated for the case of a plane electromagnetic wave of arbitrary intensity, either circularly or linearly polarized, interacting with a relativistic electron beam at an arbitrary interaction angle. The trajectories are used to derive analytic expressions for the intensity distribution of the scattered radiation. These expressions are valid in the nonlinear regime (arbitrary laser intensity) and include the generation of harmonics. The effect of interaction angle on the intensity distribution is discussed and spectra are plotted numerically for the specific cases of head-on and transverse scattering. The dependence of x-ray frequency, pulse duration, and photon flux on interaction geometry are also examined. Applications to the laser synchrotron source are discussed. There are potential advantages of both head-on and transverse interaction geometries: head-on scattering results in the generation of higher frequencies and higher photon fluxes; normal incidence scattering can result in ultrashort x-ray pulses.
A multi-axial ferroelastic switching model using the homogenized energy approach

A new constitutive modeling framework is presented to predict polarization reorientation from mechanical loading in ferroelectric materials. The modeling framework employs a homogenized energy approach to predict the reorientation of local polarization variants in response to multi-axial mechanical loading. Single crystal energy relations are given and integrated into a polycrystal model using a reduced order modeling technique that employs a set of stochastic parameters which accommodate material inhomogeneities. The homogenized energy approach provides a methodology that simplifies computations required to predict nonlinear polarization reorientation from applied stresses. The new formulation circumvents the need for large scale minimization problems of multi-well energy potentials and facilitates constitutive model integration into finite element codes and nonlinear control designs. The theory is presented, numerically implemented, and compared with experiments on lead zirconate titanate given in the literature.
High-spin gamma -ray spectroscopy in Z=83 isotopes: 199,201Bi.

The properties of high-spin states in $^{199}$,201Bi have been studied with the $^{194}$,196Pt${(}^{10}$B,5n\ensuremath{\gamma} )${}^{199}$,201Bi reactions at energies between 57 and 72 MeV. In-beam measurements of \ensuremath{\gamma}-ray excitations, \ensuremath{\gamma}-\ensuremath{\gamma}-t coincidences and correlations, \ensuremath{\gamma}-ray angular distributions, and pulsed-beam-\ensuremath{\gamma} timing were performed with Ge detectors to determine level energies, decay schemes, \ensuremath{\gamma}-ray multipolarities, ${J}^{\ensuremath{\pi}}$ assignments, and isomeric lifetimes. Levels along and near the yrast lines were established up to J\ensuremath{\approxeq}(33/2), including a number of isomers. The systematic trends of three-quasiparticle level energies in odd-mass Bi isotopes have been extended and compared with calculations involving neutron-hole configurations of the Pb-core isotones. The transition strengths extracted for $^{199}$,201Bi are compared to Pb-region values. In addition, an isomeric lifetime was measured in $^{200}\mathrm{Bi}$.
The phn island: a new genomic island encoding catabolism of polynuclear aromatic hydrocarbons

Bacteria are key in the biodegradation of polycyclic aromatic hydrocarbons (PAH), which are widespread environmental pollutants. At least six genotypes of PAH-degraders are distinguishable via phylogenies of the ring-hydroxylating dioxygenase (RHD) that initiates bacterial PAH metabolism, and a given genotype has a characteristic taxonomic distribution. The latter pattern implies each genotype may have distinct pathways for horizontal gene transfer (HGT). But, while such processes are important in the function of PAH-degrader communities, mechanisms of HGT for most RHD genotypes are unknown. Here, we report in silico and functional analyses of the phenanthrene-degrader Delftia sp. Cs1-4, a representative of the phnAFK2 RHD group. The phnAFK2 genotype predominates PAH degrader communities in some soils and sediments, but, until now, their genomic biology has not been explored. In the present studies, genes for the entire phenanthrene catabolic pathway were discovered on a novel ca. 232 kb genomic island (GEI), now termed the phn island. This GEI had characteristics of an integrative and conjugative element with a mobilization/stabilization system similar to that of SXT/R391-type GEI. But, it could not be grouped with any known GEI, and was the first member of a new GEI class. The island also carried genes predicted to encode: synthesis of quorum sensing signal molecules, fatty acid/polyhydroxyalkonate biosynthesis, a type IV secretory system, a PRTRC system, DNA mobilization functions and > 50 hypothetical proteins. The 50% G+C content of the phn gene cluster differed significantly from the 66.7% G+C level of the island as a whole and the strain Cs1-4 chromosome, indicating a divergent phylogenetic origin for the phn genes. Collectively, these studies added new insights into the genetic elements affecting the PAH biodegradation capacity of microbial communities specifically, and the potential vehicles of HGT in general.
The effect of electric field on the photoluminescence and absorption spectra of porous silicon

The effect of electric field on the photoluminescence and absorption spectra of porous silicon were investigated. An electric field applied perpendicular to the porous silicon growth direction shows a red shift in the photoluminescence peak energy and quenching of the photoluminescence intensity, whereas an electric field applied parallel to the growth direction shows photoluminescence quenching, but no clear indication of red shift. The absorption spectra also show a red shift of the absorption edge together with an increase in the absorption coefficient when an electric is field applied perpendicular to the porous silicon growth direction. The results are qualitatively similar to the quantum confined Stark effect, and provide additional support for quantum size effect as the mechanism of light emission in porous silicon.