cssi/SciSciGPT-SciSciNet huggingface dataset:
An Analysis of 1-D Smoothed Particle Hydrodynamics Kernels

In this paper, the smoothed particle hydrodynamics (SPH) kernel is analyzed, resulting in measures of merit for one-dimensional SPH. Various methods of obtaining an objective measure of the quality and accuracy of the SPH kernel are addressed. Since the kernel is the key element in the SPH methodology, this should be of primary concern to any user of SPH. The results of this work are two measures of merit, one for smooth data and one near shocks. The measure of merit for smooth data is shown to be quite accurate and a useful delineator of better and poorer kernels. The measure of merit for non-smooth data is not quite as accurate, but results indicate the kernel is much less important for these types of problems. In addition to the theory, 20 kernels are analyzed using the measure of merit demonstrating the general usefulness of the measure of merit and the individual kernels. In general, it was decided that bell-shaped kernels perform better than other shapes.
Screening of minority ions in compensated semiconductors

The screened potential of a minority impurity ion in a semiconductor below freeze-out is computed following the theory of Falicov and Cuevas. Close to the impurity the screening is of Debye type, but far from the impurity the screened potential decreases much more slowly, as $\frac{1}{{r}^{2}}$.
Deoxygenation of nitro and nitrosoaromatics by photolysis with t‐BuHgl/Kl. Regiochemistry of tert‐Butyl radical addition to nitrosoaromatics [1]

Photolysis of nitroaromatics in the presence of t-BuHgI/KI in Me2SO or DMF leads to products formed by t-Bu• addition to the nitroso compounds. Similar products are formed in the dark in the presence of K2S2O8. Nitroso or nitrobenzene is converted into N,O-di-tert-butylphenylhydroxylamine by a process involving N-tert-butylphenylhydroxylamine as an intermediate. In the presence of PTSA and KI, N-tert-butylphenylhydroxylamine predominates in Me2SO, but in DMF, the phenylhydroxylamine is reduced to N-tert-butylaniline. In a similar fashion, o-nitrosotoluene is converted into o-MeC6H4N(Bu-t)OBu-t, o-MeC6H4N(Bu-t)OH, and o-MeC6H4NHBu-t. p-Nitroso-N,N-dimethylaniline forms the N,O-di-tert-butylated derivative in the absence of acid but in the presence of PTSA/KI yields p-Me2NC6H4NHBu-t. Excellent yields of the N,O-di-tert-butylated arylhydroxylamines are formed in DMF from the nitroaromatics with para Me2N, OH, I, Br, Cl, and ortho Ph or PhNH substituents. Nitrobenzenes with p-CHO, p-PhCO, or p-CN substituents are deoxygenated to the nitroso compounds which react with t-Bu• to form the tert-butoxyamino radicals (ArṄOBu-t). In Me2SO, the amino radicals react to form ArN(HgI)OBu-t compounds which condense with the nitroso compounds to yield the azoxy compounds. With the p-CN substituent, the azoxy compound is subsequently deoxygenated and tert-butylated to yield p-NCC6H4N(Bu-t)NHC6H4CN-p. In the presence of PTSA/KI, the amino radicals are reduced to p-Y-ArNHOBu-t (Y = PhCO, CN). The compounds Y-ArN(Bu-t)OBu-t undergo photochemical degradation to yield Y-ArNHBu-t with Y = p-PhCO or p-CN in a reaction that is inhibited by I−. With PTSA/H2O/KI in Me2SO, p-Me2NC6H4N(t-Bu)OBu-t is converted into 4-(N-tert-butylimino)-2,5-cyclohexadien-1-one, p-Me2NC6H4NHBu-t, and p-tert-butylamino-m-tert-butoxy-N,N-dimethylaniline. o-MeC6H4N(Bu-t)OH reacts with PTSA/KI to form o-MeC6H4N(Bu-t)H in DMF or a mixture of the aniline and 4-(N-tert-butylimino)-3-methyl-2,5-cyclohexadien-1-one in Me2SO. In the absence of KI, only the cyclohexadienone is formed in Me2SO.
The child with frequent infections.

Abstract In this review, the normal immune system, primary and secondary immunodeficiency diseases, and nonimmunologic causes of recurrent infection have been described. With this information, any child with frequent infections can be evaluated in a sound and logical fashion. The history and physical examination are usually sufficient to rule out a significant immunodeficiency. For those in whom that is not the case, screening laboratory tests, most of which are readily available in hospitals and commercial laboratories, can and should be performed by the primary caretaker. These serve conclusively to rule in or rule out an immunodeficiency disorder in most patients and to establish the need for referral to an immunologist in the rare patient. With a few notable exceptions, the prognosis for children with immunodeficiency diseases has improved dramatically in the past two decades. This progress, fortunately, is certain to continue as the intricacies of the immune system and its genetic basis are gradually unraveled. However, the success of these new technologies depends on the ability of the primary pediatrician to identify these patients early, before permanent structural damage has occurred or a life-threatening viral infection been acquired.
Solid Modeling: The Cornerstone of Design

For any mechanical design project in an industrial setting, computer-aided design (CAD) functions as the cornerstone. Mechanical CAD systems serves as the focal point during conceptualization, design iterations, finalizing design details drawing creation and manufacturing. In most engineering technology programs, CAD, and solid modeling are offered as required courses. However, those courses often stand as “islands” of information. In the university setting, CAD is poorly integrated into the many design problems presented in courses throughout the curriculum. Frequently, students do not gain the experience of using solid models to drive their designs. Too often, their first experience of this real-world design process is “on the job”. Thus, our students are not fully prepared for industrial practice, which is contrary to the mission of engineering technology programs. This paper will present the results of a study that reviewed utilization of solid modeling throughout many baccalaureate mechanical engineering technology (MET) programs. Further, it will present some of the implementation strategies of solid modeling in upper-level, MET courses at the University of Dayton.Copyright © 2005 by ASME
Pelvic pain in adolescents.

Pain is a common reason for a visit to the doctor’s office and adolescents are no exception. The cause of acute pain is determined by physical exam, laboratory tests, and imaging. When the patient’s pain resolves with appropriate treatment, it is very satisfying to the physician. However, with chronic pain, in many cases there is no clear identifiable cause and thus no easy resolution to the problem. This can be incredibly frustrating for both patients and physicians. Teaching young physicians to understand and treat patients with chronic pain can be equally challenging. The following article outlines the main principles of caring for adolescents with chronic pelvic pain.
The signature of smoothings of complex surface singularities

Let f : (1~3, 0)-"~(t~, 0) be the germ of a complex analytic function with an isolated critical point at the origin. For e > 0 suitably small and 6 yet smaller, the space V ' = f l ( 6 ) ~ D , (where D~ denotes the closed disk of radius e about 0) is a real oriented four-manifold with boundary whose diffeomorphism type depends only on f It has been proved that V' has the homotopy type of a wedge of two-spheres; the number p o f two-spheres is readily computable. Recently an interesting formula for g was given in terms of analytic invariants of a resolution of the singularity at 0 of the complex surface f-1(0) [13]. This formula is proved by applying the Riemann-Roch theorem to the projective completions o f f l ( 0 ) and fi (6) , then canceling terms coming from the parts away from the origin. The purpose of this paper is to find a similar formula for the signature of the intersection pairing on the two-dimensional homology of the manifold V', using the Hirzebruch signature theorem instead of the Riemann-Roch theorem. Various other signature formulas are known, in higher dimensions as well as in dimension two. For f (x , y, z) of the form g(x, y) + z 2, the intersection pairing of V' is the same as a symmetrized Seifert matrix of the compound torus link {g(x, y )=0}~S 3. There is a simple formula for the signature of the symmetrized Seifert matrix of a compound link of one component [20]; hence if g-1(0) is irreducible, there is a simple formula for the signature of V' in terms of the Puiseux pairs ofg. If g1(0) has several branches at the origin, it is possible to find a Seifert matrix for the link defined by g and compute the signature [17], but this process is tedious for all but the simplest links. Formulas also exist for the signature when f(x, y, z) is of the type x a + yb + z c [10], or when f is weighted homogeneous [22]. There is in addition a formula for the signature in terms of mixed Hodge structure [233. The genus (or geometric genus) of the singularity f 1(0) (assumed Stein) is the dimension of HI(V,, C~), where ~" is a resolution of f-1(0). By combining the formulas for the signature and the number # it is possible to show that twice the genus of the singularity f 1(0) is equal to the number of positive plus the number of
Efficient algorithms for K-anonymous location privacy in participatory sensing

Location privacy is an important concern in participatory sensing applications, where users can both contribute valuable information (data reporting) as well as retrieve (location-dependent) information (query) regarding their surroundings. K-anonymity is an important measure for privacy to prevent the disclosure of personal data. In this paper, we propose a mechanism based on locality-sensitive hashing (LSH) to partition user locations into groups each containing at least K users (called spatial cloaks). The mechanism is shown to preserve both locality and K-anonymity. We then devise an efficient algorithm to answer kNN queries for any point in the spatial cloaks of arbitrary polygonal shape. Extensive simulation study shows that both algorithms have superior performance with moderate computation complexity.
Technology and Operational Considerations for Low-Heat-Rate Entry Trajectories

A broad parametric study which examines several critical aspects of low-heat-rate entry trajectories is performed. Low planform loadings associated with future winged Earth-entry vehicles coupled with the potential application of metallic thermal protection systems suggest that such trajectories are of particular interest. Some aspects of these trajectories included in this study are: three heating conditions, i.e., reference, stagnation, and windward centerline (for both laminar and turbulent flow); configuration-related factors including planform loading and hypersonic angle of attack; and mission-related factors such as crossrange and orbit inclination. Results indicate benefits in the design of thermal protection systems are to be gained by utilizing moderate angles of attack, as opposed to high lift coefficients coupled with high angles of attack, during entry. An assessment of design and technology implications is made. Nomenclature e.g. = center of gravity in percent of body reference length measured from the disappearing apex of the nose CL . = lift coefficient cp —
A characterization of convexity and central symmetry for planar polygonal sets

LetS be a compact set inR 2 with nonempty interior,L(u,k) be a line 〈u, x〉 =k, and ζ u (k) be the linear Lebesgue measure ofS∩L(u,k). It is well known that for a convexS, ζ u (k) is unimodal, that is, as a function ofk, it is first non-decreasing and then nonincreasing for everyu∈R 2. Further, ifS is centrally symmetric with respect toM, ζ u (k) achieves maximum whenL(u, k) passes throughM. Converse propositions are considered in this paper for polygonalS with Jordan boundary. It is shown that unimodality alone does not suffice for convexity. However, if ζ u (k) achieves maximum wheneverL(u, k) passes through some fixed pointM then unimodality yields convexity as well as central symmetry. It is also shown that continuity of ζ u (k) in the interior of its support implies convexity ofS. This last result, however, is false for non-polygonal sets.
U-shaped masking functions under backward masking by pattern mask

Tests were made of the influence of target luminance, target and mask luminance, retinal position, and observer’s task on visual backward masking by a patterned mask. U-shaped masking functions were obtained when the performance of observers was equated through manipulation of either the experimental task or the retinal position of the target.
Transactions: Electric braking (or railroad and Urban transit equipment

THE PURPOSE of this paper is to outline the present status of electric braking in the railroad and urban transit fields and to point out possible solutions of future braking problems particularly those arising from increasing speeds.
Emotionality and Performance on Competitional and Noncompetitional Paired-Associates

18 male college Ss scoring in the extreme quintiles on a unidimensional “emotionality” scale (Em) were tested on competitive and noncompetitive paired-associates. Results demonstrated that the low Em Ss made significantly fewer errors on both competitive and noncompetitive associates and required significantly fewer trials to reach criterion on the noncompetitive associates than did the high Em Ss. The results were compared to those of Spence, et al. (1963) for high- and low-“anxious” Ss on these same word pairs. Discrepant findings were interpreted as reflecting different operational measures of “anxiety” employed in the two studies.
Adaptive spectroscopy for rapid chemical identification

Spectroscopic chemical identification is fundamentally a classification task where sensor measurements are compared to a library of known compounds with the hope of determining an unambiguous match. When the measurement signal-to-noise ratio (SNR) is very low (e.g. from short exposure times, weak analyte signatures, etc.), classification can become very challenging, requiring a multiple-measurement framework such as sequential hypothesis testing, and dramatically extending the time required to classify the sample. There are a wide variety of defense, security, and medical applications where rapid identification is essential, and hence such delays are disastrous. In this paper, we discuss an approach for adaptive spectroscopic detection where the introduction of a tunable spectral filter enables the system to measure the projection of the sample spectrum along arbitrary bases in the spectral domain. The net effect is a significant reduction in time-to-decision in low SNR cases. We describe the general operation of such an instrument, present results from initial simulations, and report on our experimental progress.
Hermeneutics, Social Constructionism and Other Items of Intellectual Fashion: Intimations for Clinical Science

Two fashionable contemporary intellectual movements, hermeneutics and social constructionism, are explored and contrasted. The relationships among anti-foundationalism, hermeneutics, and relativism, on the one hand, and conceptualizations of psychotherapy and behavior therapy, on the other, are examined.
Translational genomics for bioenergy production: there's room for more than one model.

Lawrence and Walbot's commentary ([Lawrence and Walbot, 2007][1]) on the application of translational genomics in developing energy crops focused on maize as the model species for biofuel research. Here, we discuss the reasons why other model species will also make important contributions. To fully
Pyrolysis studies of methylcyclohexane and oxidation studies of methylcyclohexane and methylcyclohexane/toluene blends

Abstract High-temperature (1050–1200 K) pyrolysis studies of pure methylcyclohexane (MCH) and oxidation studies of pure MCH and MCH/toluene blends were performed in the Princeton Turbulent Flow Reactor. Since MCH is a proposed endothermic jet fuel, as well as a possibly significant constituent of current commercial automotive and aviation fuel blends, high-temperature studies of MCH provide an understanding of its decay characteristics in both aircraft and automobile engine environments. Ethene, 1,3-butadiene, methane, and propene were found to be the major intermediates produced by MCH pyrolysis. Oxidation of MCH also produced the same intermediates. As expected, the observed oxidation reaction rates were faster than the pyrolysis reaction rates. The MCH/toluene-blend oxidation experiments (1160 K and φ = ∼ 1.3) revealed that, while the two fuels appear to oxidize by independent mechanisms, the rates of oxidation of both fuels are strongly related to the initial concentration of MCH.
On the Definition of Tax Neutrality: Distributional and Welfare Implications of Policy Alternatives

The fairness of a tax change is often judged by examining its impact on tax burdens or net incomes of different income classes. Two competing definitions of tax neutrality give surprisingly different and conflicting answers to the fairness question. If the objective is to maximize welfare, the Lorenz dominance principle offers guidance as to how tax neutrality should be defined. In the presence of asymmetric information the different definitions of tax neutrality make it possible for politicians to adopt the definition that favors their constituency and/or serves a particular political agenda. The median voter model is applied to explore the definition of neutrality in a democracy. In general, decisions by rational self-interested voters and politicians may, but do not necessarily, result in the definition that leads to Lorenz dominance.
Hemophagocytic lymphohistiocytosis in a patient with Goodpasture's syndrome: a rare clinical association.

Patient: Female, 31 Final Diagnosis: Hemophagocytic lymphohistiocytosis (LHL) Symptoms: Hemopthysis Medication: — Clinical Procedure: — Specialty: Oncology Objective: Rare disease Background: Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening clinical syndrome. HLH can occur in the setting of an autoimmune disease, chronic immunosuppression, malignancy, and infection. We discuss a rare case of a young woman who was diagnosed with Goodpasture’s syndrome that was most likely complicated by HLH. To the best of our knowledge, this is the first report of HLH in the setting of this rare autoimmune disease. Case Report: A 31-year-old woman who was diagnosed with Goodpasture’s syndrome 7 years prior presented with febrile neutropenia. She was initially receiving treatment with azathioprine and prednisone, which was subsequently switched to hydroxychloroquine. Over time, she had developed polyarthritis and was later diagnosed with MPO-ANCA-positive vasculitides. On this admission, her clinical status deteriorated from persistent pancytopenia. This was initially attributed to the immunosuppressive effect of hydroxychloroquine. A bone marrow biopsy was performed and revealed hypercellular bone marrow without any cytogenetic abnormalities. Due to a prolonged pancytopenia thought to be of autoimmune etiology, treatment with high-dose steroids was initiated. With the persistent febrile episodes, hepatosplenomegaly on examination, and laboratory workup that revealed hyperferritinemia and pancytopenia, HLH syndrome was suspected. A repeat bone marrow biopsy confirmed this diagnosis with the presence of hemophagocytosis, demonstrated by the presence of histiocytes engulfing erythroid cells. She also met 5 of 8 diagnostic criteria, which confirmed the diagnosis of HLH. The patient eventually died despite aggressive treatment with high-dose steroid therapy for her autoimmune disorder, as well intravenous antibiotics and supportive care for her underlying infections. Conclusions: HLH is a syndrome marked by a hyper-inflammatory state aggravated by specific triggers. To make the diagnosis of HLH, at least 5 of the 8 criteria must be met. Treatment involves suppression of the overwhelming inflammatory response by the use of immunomodulators. The mortality rate can range from 50–90% due to delayed recognition and onset of treatment. Here, we present a rare case of Goodpasture’s syndrome with overlap and pauci-immune vasculitis, which may have triggered the HLH. This correlation has not been described before in the literature.
Indentation: A simple, nondestructive method for characterizing the mechanical and transport properties of pH-sensitive hydrogels

We use instrumented indentation to characterize the mechanical and transport behavior of a pH-sensitive hydrogel in various aqueous buffer solutions. In the measurement, an indenter is pressed to a fixed depth into a hydrogel disk and the load on the indenter is recorded as a function of time. By analyzing the load–relaxation curve using the theory of poroelasticity, the elastic constants of the hydrogel and the diffusivity of water in the gel can be evaluated. We investigate how the pH and ionic strength of the buffer solution, the hydrogel cross-link density, and the density of functional groups on the polymer backbone affect the properties of the hydrogel. This work demonstrates the utility of indentation techniques in the characterization of pH-sensitive hydrogels.
Tidal induced regulation of nitrogen fixation activity (C2H4 production) in a Georgia Salt Marsh

Nitrogen fixation potential, determined by the acetylene reduction technique, was measured at fourteen sites across a Georgia salt marsh. The transect spanned (1) tall and short Spartina alterniflora, and natural Juncus and Salicornia monocultures and (2) small tidal creek which usually floods over a levee into a short Spartina marsh during high tides. Spring tides usually flood the entire marsh and enter the Juncus zone. Nitrogen fixation potential in the soil was related to sites of daily tidal inundation and not to interstitial salinity. We also artificially altered the salinity in cores from short and tall Spartina zones to investigate whether nitrogen-fixing populations were tolerant to fluctuations in salt concentration. Results indicate that populations in the marsh are diverse and fluctuate monthly with respect to salinity tolerance in Sapelo Island salt marsh soils.
Mirror, Mirror on the Wall: The Effect of Time Spent Grooming on Earnings

To most economists, personal grooming is a non-market activity. The standard view is that time spent in non-market activities is counterproductive as it reduces work effort and job commitment. But grooming may be different. Grooming provides an important source of communication about workers, their values and personalities. There is reason to believe that certain productive personality traits may be inferred on the basis of personal grooming. In this paper, we use data from the American Time Use survey’s pooled cross-section 2003-2007 to investigate the effect of additional time spent grooming on earnings. The results show that the effect of grooming on earnings differs significantly by gender and race.
Shear-Stabilized Rolling Behavior of E. coli Examined with Simulations

Escherichia coli exhibit both shear-stabilized rolling and a transition to stationary adhesion while adhering in fluid flow. Understanding the mechanism by which this shear-enhanced adhesion occurs is an important step in understanding bacterial pathogenesis. In this work, simulations are used to investigate the relative contributions of fimbrial deformation and bond transitions to the rolling and stationary adhesion of E. coli. Each E. coli body is surrounded by many long, thin fimbriae terminating in a single FimH receptor that is capable of forming a catch bond with mannose. As simulated cells progress along a mannosylated surface under flow, the fimbriae bend and buckle as they interact with the surface, and FimH-mannose bonds form and break according to a two-state, allosteric catch-bond model. In simulations, shear-stabilized rolling resulted from an increase in the low-affinity bond number due to increased fimbrial deformation with shear. Catch-bond formation did not occur during cell rolling, but instead led to the transition to stationary adhesion. In contrast, in leukocyte and platelet systems, catch bonds appear to be involved in the stabilization of rolling, and integrin activation is required for stationary adhesion.
Activation of Luteinizing Hormone β Gene by Gonadotropin-releasing Hormone Requires the Synergy of Early Growth Response-1 and Steroidogenic Factor-1

We have previously shown that early growth response (Egr) 1-deficient mice exhibit female infertility, reflecting a luteinizing hormone (LH) beta deficiency. Egr-1 activates the LHbeta gene in vitro through synergy with steroidogenic factor-1 (SF-1), a protein required for gonadotrope function. To test if this synergy is essential for gonadotropin-releasing hormone (GnRH) stimulation of LHbeta, we examined the activity of the LHbeta promoter in the gonadotrope cell line LbetaT2. GnRH markedly stimulated the LHbeta promoter (15-fold). Mutation of either Egr-1 or SF-1 elements within the LHbeta promoter attenuated this stimulation, whereas mutation of both promoter elements abrogated GnRH induction of the LHbeta promoter. Furthermore, GnRH stimulated Egr-1 but not SF-1 expression in LbetaT2 cells. Importantly, overexpression of Egr-1 alone was sufficient to enhance LHbeta expression. Although other Egr proteins are expressed in LbetaT2 cells and are capable of interacting with SF-1, GnRH stimulation of Egr-1 was the most robust. We also found that the nuclear receptor DAX-1, a repressor of SF-1 activity, reduced Egr-1-SF-1 synergy and diminished GnRH stimulation of the LHbeta promoter. We conclude that the synergy between Egr-1 and SF-1 is essential for GnRH stimulation of the LHbeta gene and plays a central role in the dynamic regulation of LHbeta expression.
Proportion of type 2 diabetes cases resulting from impaired fetal growth.

OBJECTIVE: During the past decade, several researchers have demonstrated a higher risk of type 2 diabetes in relation to lower birth weight. This theory, referred to as the "thrifty phenotype" hypothesis, postulates that impaired fetal growth predisposes individuals to the development of diabetes and other metabolic abnormalities. This article examines the importance of fetal growth in the etiology of diabetes by estimating the proportion of diabetes cases associated with this exposure. RESEARCH DESIGN AND METHODS: The importance of an exposure or its correlate as a potential cause of a disease can be assessed by estimating the proportion of cases that could be prevented if the exposure was eliminated from a defined population. This proportion is referred to as the population-attributable fraction (PAF). Published studies of the association between diabetes and birth weight were reviewed and selected for further analysis if data were presented that enabled PAF calculation. In addition, PAFs were calculated for higher birth weight cutoffs because researchers have postulated that the lowest birth weight category may not capture all cases of fetal growth retardation. Studies have shown that exposure classified in this broader manner can produce unbiased PAF estimates, even if many subjects are falsely classified as exposed. RESULTS: PAFs for the lowest birth weight category ranged from 0.01 to 0.25. In this analysis, PAFs for diabetes did not exceed 0.35. In contrast, >50% of diabetes cases in the First National Health and Nutrition Examination Survey Epidemiologic Follow-Up Study were attributable to excess adiposity as reflected by a BMI of > or =26 kg/m2 (PAF >0.50). CONCLUSIONS: Impaired fetal growth or its correlates account for a minority (
The effects of lithium chloride on pattern formation in Tetrahymena thermophila.

Abstract Lithium ions have long been known to exert dramatic effects on the specification of cell fates in multicellular systems. We have analyzed the effects of Li+ on intracellular patterning in a complex unicellular organism, the ciliate Tetrahymena thermophila. LiCl does not affect the locations of major structural landmarks in the cortical region of wild-type cells and does not modify the phenotype of pattern-mutant cells. However, in all strains studied LiCl differentially affects early stages of oral development. It initially triggers a slow regression of oral primordia, which is followed by an excessive proliferation of basal bodies that leads to a hypertrophy of the ciliature of the cell's feeding organelle. This hypertrophy mimics the effects of the membranellar-pattern-D mutation, the phenotype of which is enhanced in the presence of LiCl. These effects were partially reversed by myo-inositol; however, neomycin failed to mimic the effects of LiCl. Thus, although lithium ions have major cellular effects on Tetrahymena , they do not influence the specification of the body plan in a manner analogous to that observed in multicellular organisms and may work in part through mechanisms other than the now-classical inositol-phosphate cycle.
Ultrafine-grained magnetite in deep-sea sediments: Possible bacterial magnetofossils

A new extraction technique now permits ultrafine magnetite crystals to be separated from a variety of deep-sea sediments. Morphologic characterization of these particles with transmission electron microscopy reveals the presence of several distinct crystal types, some of which closely resemble those formed by the magnetotactic bacteria. The apparently biogenic magnetite particles are of single-domain size and dominate the population in calcareous deep-sea sediments. Bacterially precipitated magnetite may therefore be a major source of the stable magnetic remanence in some marine sediments. These objects possibly constitute the smallest mineral fossils yet recovered from the sedimentary record.
Artificial bee colony algorithm for CONWIP production control system in a multi-product multi-machine manufacturing environment

In this paper, a multi-product multi-machine serial production line operated under a constant-work-in-process protocol is considered. A mathematical model for the system is first presented, and then an artificial bee colony optimization algorithm is applied to simultaneously find the optimal work-in-process inventory level as well as job sequence order in order to minimize the overall makespan time. Unlike many existing approaches, which are based on deterministic search algorithms such as nonlinear programming and mixed integer programming, the proposed method does not use a linearized or simplified model of the system. A production line simulator implemented on MATLAB is, instead, employed to model the highly nonlinear dynamics of the production line and is used to evaluate the candidate solutions. The efficiency of the proposed approach, even for systems of large sizes, is validated via numerical simulations.
Molecular dynamics simulation of reverse micelles in supercritical carbon dioxide

We have studied surfactants and reverse micelles in supercritical carbon dioxide (SCO2) by molecular dynamics simulation using molecular potential models that we have developed for this purpose. In this work we present simulation results suggesting how varying the surfactant molecular architecture and chemistry may affect the structure and properties of reverse micelles in SCO2. We focus on a dichain surfactant, (C7H15)(C7F15)CHSO4-Na+, which forms reverse micelles with aqueous cores in SCO2.
An intelligent tutor for high school algebra problems: Oregon State University

This is an ongoing research project whose goal is to build a system for tutoring students to interpret and solve high school algebra level word problems. Until now, the major emphasis has been on the development of a model of problem solving based on protocols between tutors and students. Our model currently consists of four sets of production rules which account for strategies, computations on problem entities, algebraic manipulations, and semantics of the problem statement.
The near-infrared phase curve of the Uranian rings

Abstract We performed K-band observations of the Uranian rings during the 1985 opposition in order to determine if a measurable opposition effect occurs. The investigation, carried out over a period of several months and over a range of 0.021° to 2.5° in solar phase angle, revealed an opposition surge of approximately 0.2 mag. This result is interpreted in terms of two simple models: mutual shadowing and surface microstructure. If entirely due to interparticle shadowing, the brightening implies a ring thickness inconsistent with surface mass densities derived from dynamical considerations. If the surge results from surface effects, the ring particles have dark surfaces with a porosity comparable to that of terrestrial snow.
Adaptive Fourier series modeling of time-varying evoked potentials: study of human somatosensory evoked response to etomidate anesthetic

Abstract Evoked potentials (EPs) have traditionally been analyzed in time domain, with amplitude and latency of various signal components used in clinical interpretation. A new approach, called adaptive Fourier series modeling (FSM), is presented here. Dynamic changes in magnitudes of Fourier coefficients are analyzed for diagnostic purposes. In order to estimate the time-varying changes in the Fourier coefficients of noisy signals, a least mean-square filtering algorithm is applied. Results of computer simulations as well as experimental data are presented. Time varying trends are presented in a new compressed evoked spectrum format. These techniques are applied to the study of alterations in human somatosensory EPs caused by the intravenous administration of etomidate during neurosurgical procedures. Amplitude increases of the order of 200–500% occurring within a time span of about 100 sec were captured. Due to its superior convergence properties, the adaptive FSM technique estimates more rapid changes in amplitude and latency than exponentially weighted averaging or moving window averaging schemes.
Multiracial Competence in Social Work: Recommendations for Culturally Attuned Work with Multiracial People

According to the 2010 U.S. census, approximately 9 million individuals report multiracial identities. By the year 2050, as many as one in five Americans could claim a multiracial background. Despite this population growth, a review of recent empirical and theoretical literature in social work suggests a disproportionate lack of attention to issues ofmultiraciality. Instead, social work practice models remain embedded in traditional societal discourses of race and culture that often exclude or marginalize the experiences of multiracial individuals and families.This article summarizes recommendations following the domains of awareness, knowledge, and skills in the NASW Standards for Cultural Competence in Social Work Practice to support culturally attuned social work practice with multiracial people. The authors argue that a culturally attuned practice approach--one that is inclusive of multiraciality--is not only timely, but also consistent with the profession's ethical obligation to provide culturally relevant services to all consumers and clients.
Contact dermatitis in athletes

Athletes face numerous hazards in their daily activities. An athlete's skin, in particular, endures repeated exposure to trauma, heat, moisture, and numerous allergens and chemicals. These factors combine with other unique and less well-defined genetically predisposing factors in the athlete's skin to cause both allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD). As with other cases of contact dermatitis, these eruptions in athletes present as a spectrum of acute to subacute to chronic dermatitis. Recognizing the unique environmental irritants and allergens encountered by athletes is paramount to facilitate appropriate therapy and prevention. This review comprehensively examines the literature on contact dermatitis in athletes. The different types of contact dermatitis have been classified under sport-specific subheadings. Furthermore, within each subheading, both ACD and ICD types are discussed.
Image reconstruction from cylindrically averaged diffraction intensities

The problem of reconstructing a three-dimensional scatterer from measurements of the cylindrical average of the intensity of its Fourier transform is discussed. Reconstruction involves phase retrieval as well as unraveling the effects of cylindrical averaging. The application area considered is x-ray analysis of polymer fibers, and other systems, that consist of collections of rotationally disordered particles. Diffraction from these types of specimens and reconstruction algorithms are described. The particles in these applications often exhibit helical symmetry and the effect of this on reconstruction is described.
Impaired Students: Applying the Therapeutic Process Model to Graduate Training Programs.

This article updates and adds to the literature on graduate trainee impairment provided by L. Forrest, N. Elman, S. Gizara, and T. Vacha-Haase (1999) in their comprehensive literature review. Based on recommendations by Forrest et al., a program model for dealing with impaired trainees is proposed. The 5-step therapeutic process model includes (a) informed consent, (b) intake and assessment, (c) evaluation, (d) treatment planning and follow-up, and (e) termination. Each step is explained within the context of graduate training programs, and key points to consider are discussed.
Multiplicative updates outperform generic no-regret learning in congestion games: extended abstract

We study the outcome of natural learning algorithms in atomic congestion games. Atomic congestion games have a wide variety of equilibria often with vastly differing social costs. We show that in almost all such games, the well-known multiplicative-weights learning algorithm results in convergence to pure equilibria. Our results show that natural learning behavior can avoid bad outcomes predicted by the price of anarchy in atomic congestion games such as the load-balancing game introduced by Koutsoupias and Papadimitriou, which has super-constant price of anarchy and has correlated equilibria that are exponentially worse than any mixed Nash equilibrium.Our results identify a set of mixed Nash equilibria that we call weakly stable equilibria. Our notion of weakly stable is defined game-theoretically, but we show that this property holds whenever a stability criterion from the theory of dynamical systems is satisfied. This allows us to show that in every congestion game, the distribution of play converges to the set of weakly stable equilibria. Pure Nash equilibria are weakly stable, and we show using techniques from algebraic geometry that the converse is true with probability 1 when congestion costs are selected at random independently on each edge (from any monotonically parametrized distribution). We further extend our results to show that players can use algorithms with different (sufficiently small) learning rates, i.e. they can trade off convergence speed and long term average regret differently.
Attachment of a sling rescue suture to Midurethral tape for management of potential postoperative voiding dysfunction.

Aims To investigate the utility of a polypropylene sling rescue suture (SRS) attached to mid-portion of the mid-urethral sling tape procedure for in office sling loosening/release using a defined algorithm. Methods A surgical database search was performed for slings performed by the authors. During the course of the procedure a polypropylene suture was passed through the mid-portion of the sling tape and allowed to exit through the vaginal mucosa closure such that the tail of the suture loop rested in the vagina. Patients were managed by a predetermined algorithm to make decisions about (1) in office polypropylene suture removal, (2) manipulation of polypropylene suture in attempt to loosen the sling, and (3) localization and incision of the sling tape in the office using polypropylene suture. Results One hundred eighty-four cases were identified, 70/184 of which were outpatient slings, and 114/184 of which had reconstructive surgery and a sling procedure. In the outpatient sling group 2/70 (3%) had resolution of voiding dysfunction with sling manipulation using polypropylene suture, 2/70 (3%) required sling excision in office. In the group with concomitant pelvic reconstruction, 4/114 had elevated postvoid residuals and ultimately required sling excision. 6/184 (3%) in the entire group required sling excision in the office. 178/184 (97%) had normal voiding. Conclusions The polypropylene suture facilitated easy release of obstructive slings. It was successful in normalizing the voiding function in patients with disrupted voiding pattern, but not in those with high post-void residuals who had failed a trial of intermittent catherization. Neurourol. Urodynam. 28:990–994, 2009. © 2009 Wiley-Liss, Inc.
Sodium doping in ZnO crystals

ZnO bulk single crystals were doped with sodium by thermal diffusion. Positron annihilations spectroscopy confirms the filling of zinc vacancies, to >6 μm deep in the bulk. Secondary-ion mass spectrometry measurement shows the diffusion of sodium up to 8 μm with concentration (1–3.5) × 1017 cm−3. Broad photoluminescence excitation peak at 3.1 eV, with onset appearance at 3.15 eV in Na:ZnO, is attributed to an electronic transition from a NaZn level at ∼(220–270) meV to the conduction band. Resistivity in Na doped ZnO crystals increases up to (4–5) orders of magnitude at room temperature.
Insights into biological functions across species: examining the role of Rab proteins in YIP1 family function

The YIP1 family comprises an evolutionarily conserved group of membrane proteins, which share the ability to bind di-prenylated Rab proteins. The biochemical capability of YIP1 family proteins suggests a possible role in the cycle of physical localization of Rab proteins between their cognate membranes and the cytosol. YIP1 is essential for viability in yeast and a deletion of YIP1 can be rescued with the human homologue YIP1A. We have made use of this evolutionary conservation of function to generate a series of mutant alleles of YIP1 to investigate the biological role of Yip1p. Our findings indicate evidence for the participation of Yip1p in both Rab and COPII protein function; at present, we are not able to distinguish between the models that these roles represent, i.e. independent or dependent activities of Yip1p.
Exploiting Exploration Strategies in Repeated Normal Form Security Games

We describe a method for the estimation of an opponent's utility matrix in a finite repeated game, given that he selects his actions by a known deterministic algorithm with some unknown parameters. We also investigate the prediction, based on the utility matrix estimate, of this opponent's future actions, and a simple method by which the opponent can counter these efforts. These are posed as a feasibility problem and a convex optimization problem, respectively. Simulation results are also presented.
Firm Level Determinants of International Certification: Evidence from Ethiopia

Summary This paper investigates a wide range of plausible determinants of international certification (IC) in Ethiopia. While past studies focus on the effect of international laws, the findings of this paper suggest that domestic pressure and firm capability are also equally important. Besides export orientation, we find international connectivity, sources of finance such as credit from local banks or local customers, and manager’s human capital as significant determinants of IC. Once such factors are controlled for, firm size, sector, and nationality of owner, appear not to matter. Furthermore, we find that certification may not necessarily enhance business performance in the short run.
Entropy optimized morphological shared-weight neural networks

Morphological shared-weight neural networks previously demonstrated performance superior to that of MACE filters and standard shared-weight neural networks for target detection. Empirical analysis showed that entropy measures of the morphological shared-weight networks were consistently higher than those of the standard shared-weight neural networks. Based on this observation, an entropy maximization term was added to the morphological shared-weight network objective function. In this paper, target detection results are presented for morphological shared-weight networks trained with and without entropy terms.
Molecular dynamics study of the threshold displacement energy in MgO

Abstract Molecular dynamics (MD) simulations were used to obtain threshold displacement energies (Ed) of atoms along specific directions in MgO. In the simulation, an atom in the center of the cell was given kinetic energy along a specific crystallographic direction. The positions and site potential energies of the primary knock-on atom (pka) and all neighboring atoms were monitored as a function of time. In this work, the minimum displacement energies that formed stable Frenkel pair defects were determined to be 90±2 eV along the [1 3 1] direction for magnesium and 67±3 eV along the [1 2 1] direction for oxygen. The MD simulations reveal that atomic displacement events consist of replacement collision sequences in addition to the production of Frenkel pairs.
The Corrosion Resistance of an Aluminum Alloy Coated with Polysilazane-Derived Ceramics

Abstract Aluminum alloy AA 6061-T6 substrates were dip-coated in a poly-N- methylsilazane, —[CH2SiNCH3]n—, solution with cross-linking catalyst. The coatings were pyrolyzed at 400°C in order to transform them into an amorphous Si3N4 ceramic coating. The coated substrates exhibited improved corrosion and pitting resistance, and showed little degradation in polarization resistance after 21 days of exposure in 3.5% NaCl solution.
Slipping, sliding and stability: locomotor strategies for overcoming low-friction surfaces

Legged terrestrial animals must avoid falling while negotiating unexpected perturbations inherent to their structurally complex environments. Among humans, fatal and nonfatal injuries frequently result from slip-induced falls precipitated by sudden unexpected encounters with low-friction surfaces. Although studies using walking human models have identified some causes of falls and mechanisms underlying slip prevention, it is unclear whether these apply to various locomotor speeds and other species. We used high-speed video and inverse dynamics to investigate the locomotor biomechanics of helmeted guinea fowl traversing slippery surfaces at variable running speeds (1.3-3.6 m s(-1)). Falls were circumvented when limb contact angles exceeded 70 deg, though lower angles were tolerated at faster running speeds (>3.0 m s(-1)). These prerequisites permitted a forward shift of the body's center of mass over the limb's base of support, which kept slip distances below 10 cm (the threshold distance for falls) and maximized the vertical ground reaction forces, thus facilitating limb retraction and the conclusion of the stance phase. These postural control strategies for slip avoidance parallel those in humans, demonstrating the applicability of these strategies across locomotor gaits and the potential for guinea fowl as an insightful model for invasive approaches to understanding limb neuromuscular control on slippery surfaces.
Achieving quality patient-ventilator management: advancing evidence-based nursing care

This article presents suggestions for nurses to gain skill, competence, and comfort in caring for critically ill patients receiving mechanical ventilatory support, with a specific focus on education strategies and building communication skills with these challenging nonverbal patients. Engaging in evidence-based practice projects at the unit level and participating in or leading research studies are key ways nurses can contribute to improving outcomes for patients receiving mechanical ventilation. Suggestions are offered for evidence-based practice projects and possible research studies to improve outcomes and advance the science in an effort to achieve quality patient-ventilator management in intensive care units.