cssi/SciSciGPT-SciSciNet huggingface dataset:
Experimental and Numerical Study of Soft Tissue Surrogate Behavior Under Ballistic Loading

Studying the high strain rate behavior of soft tissues and soft tissue surrogates is of interest to improve the understanding of injury mechanisms during blast and impact events. Tests such as the split Hopkinson pressure bar have been successfully used to characterize material behavior at high strain rates under simple loading conditions. However, experiments involving more complex stress states are needed for the validation of constitutive models and numerical simulation techniques for fast transient events. In particular, for the case of ballistic injuries, controlled tests that can better reflect the effects induced by a penetrating projectile are of interest. This paper presents an experiment that tries to achieve that goal. The experimental setup involves a cylindrical test sample made of a translucent soft tissue surrogate that has a small pre-made cylindrical channel along its axis. A small caliber projectile is fired through the pre-made channel at representative speeds using an air rifle. High speed video is used in conjunction with specialized software to generate data for model validation.A Lagrangian Finite Element Method (FEM) model was prepared in ABAQUS/Explicit to simulate the experiments. Different hyperelastic constitutive models were explored to represent the behavior of the soft tissue surrogate and the required material properties were obtained from high strain rate test data reported in the open literature. The simulation results corresponding to each constitutive model considered were qualitatively compared against the experimental data for a single projectile speed. The constitutive model that provided the closest match was then used to perform an additional simulation at a different projectile velocity and quantitative comparisons between numerical and experimental results were made. The comparisons showed that the Marlow hyperelastic model available in ABAQUS/Explicit was able to produce a good representation of the soft tissue surrogate behavior observed experimentally at the two projectile speeds considered.Copyright © 2012 by ASME
Herbivory and seedling establishment in post-fire southern California chaparral

A caging experiment was conducted to determine the effects of herbivorous insects and small mammals on first-year establishment of Ceanothus greggii (ceanothus) and Adenostoma fasciculatum (chamise) seedlings in post-fire chaparral. Insect herbivory had no effect on either species. Observations of tagged seedlings revealed that nearly all herbivory was due to small mammals, and was preferentially greater for ceanothus. When seedlings were protected from herbivory chamise experienced higher mortality. Small-mammal herbivore pressure on ceanothus seedlings tipped the survivorship balance for unprotected seedlings in favor of chamise, allowing a relatively higher establishment of chamise seedlings during the first growing season after chaparral fire.
Modeling of droplet entrainment phenomena at a quench front

Abstract The phenomena of droplet entrainment at a quench front is of practical importance as a clear understanding of the underlying mechanisms required to effectively calculate the interfacial mass, momentum, and energy transfer, which characterizes nuclear reactor safety, system design, analysis, and performance. The present study proposes a model for droplet entrainment at a quench front that is based on the best-understood physics related to the Lagrangian quenching phenomenon characteristic to light water reactor (LWR) safety analysis. The model is based on a film boundary layer and stability analysis that attempts to match the characteristic time and length scales of the entrainment phenomenon. This model has been developed such that direct implementation can be made into any two-phase flow simulation code with a three-field (continuous liquid, droplet, and vapor) flow model. Comparisons with integrated transient test data independent of those used for model development have been performed to verify the applicability of the proposed model for the prediction of the entrainment rate of liquid droplets at a quench front under typical reflood conditions envisioned in LWRs.
BILATERAL SINGLE URETERAL ECTOPIA: DIFFICULTY ATTAINING CONTINENCE USING STANDARD BLADDER NECK REPAIR

AbstractPurpose: We reviewed the surgical results of the management of bilateral single ureteral ectopia, a rare congenital cause of severe urinary incontinence.Materials and Methods: We reviewed the records of 6 girls and 1 male infant who presented to 1 institution with this diagnosis in a 10-year period.Results: All patients were incontinent and 3 had undergone ureteral reimplantation as an initial procedure with persistent postoperative wetting. Of the 5 patients who underwent a total of 8 attempts at increasing bladder outlet resistance, including 3 Young-Dees-Leadbetter, 2 Kropp, 1 Stamey, 1 Burch and 1 pubovaginal sling procedure, 2 also underwent simultaneous bladder augmentation to increase bladder capacity. However, none of these children had satisfactory continence after the continence procedure. Three of these patients who subsequently underwent appendicovesicostomy with bladder neck closure are continent. The 2 remaining patients underwent initial appendicovesicostomy with bladder neck closur...
Infectious risks of blood transfusions: Recent advances in testing technologies and new approaches to surveillance and decision-making

Introduction Despite impressive progress in reducing risk of established transfusion-transmitted infectious diseases (TTIDs), new emerging infectious disease (EID) threats continue to be identified and cause pressure to expand deferrals and testing in order to maintain the safety of transfusions. Aims Review recent progress in developing approaches for estimation of residual risk and test efficacy for established TTIDs, as well as new approaches for systematic surveillance and assessment of EIDs that may threaten the blood supply. Methods Summarize recent publications and initiatives of the global blood banking community directed at reducing risk of traditional TTIDs as well as recent responses to EID threats. Results Implementation of enhanced serological assays and nucleic acid amplification technologies (NAT) has virtually eliminated risks of major TTIDs. Formal approaches have recently been developed to monitor and respond to EIDs by examining their properties with respect to transmissibility and potential for causing significant disease in transfusion recipients. New tools for quantitative risk assessment are under development to facilitate rigorous evaluation of scientific evidence, while also formally soliciting and considering public perception and fear and health economic realities. Conclusion These ongoing efforts at refining our risk surveillance, assessment and decision analysis tools, coupled with focused research to quantify risks and evaluate interventions, presage an era of sustained safety and enhanced public trust in the blood supply.
Measurement of wavefront phase delay and optical density in apodized coronagraphic mask materials

The development of stellar coronagraphs for exoplanet detection requires apodized occulting masks to effectively remove the light from the central star while allowing planet light to propagate past. One possible implementation, a gray-scale mask, includes the placement of micron-scale neutral density light absorbing patterns using High Energy Beam Sensitive (HEBS) glass. A second implementation, binary masks, uses micron-scale diffractive/reflective patterns. Coronagraph performance will be influenced by wavefront phase shifts introduced by the masks, hence accurate characterization of the fundamental optical properties, namely optical density (OD), phase advance/delay and optical constants of the material is needed for occulter design, development and modeling. In this paper we describe an interferometric apparatus that measures wavefront phase advance/delay through grey-scale and binary masks as functions of wavelength and optical density, which is also measured. Results for HEBS gray-scale masks will be presented along with ellipsometric measurements of optical constants.
Nazis and the Cinema – By Susan Tegel

In this comprehensive and informative survey of cinema under the Third Reich, the author tells an often surprising story. When the Nazis took power, the German film industry was the second largest ...
The effect of multi-plate array spacing on grid-generated turbulence

Abstract This study compares measurements of the streamwise integral length scale, the root mean square (r.m.s.) of the streamwise component of velocity, and the r.m.s. of the normal component of velocity obtained at the exit of a plate array with measurements obtained at the same position for the “open pipe case”. The “open pipe case” is defined as the empty tube, without the plates in place, i.e., the apparatus becomes grid flow entering an unobstructed pipe. In general, this study finds that the length scale in the streamwise direction decreases with increasing plate spacing while the r.m.s. velocity in the streamwise direction increases as the plate spacing increases for fixed values of x/M (i.e., the streamwise direction to mesh-spacing ratio). These measured trends are consistent with a simple model based on vortex elements and conservation of angular momentum.
The effect of Sn, AI, and N on the hot ductility of a carbon-manganese steel between 700° and 1200 °C

The effect of Sn and Al-N additions on the hot ductility of a C-Mn steel has been investigated in a series of laboratory melted steels. The addition of either Sn or Al-N produced a similar degree of ductility loss and embrittlement at 800° and 900 °C while no ductility loss was found at 1000 °C. The combination of Sn and Al-N increased the severity of embrittlement and hot cracking and extended the temperature range of ductility loss from 800° to 1000 °C.
Ibibio verb morphology

SYNOPSIS This article describes the affixes and tone changes involved in the construction of Ibibio tenses. Ibibio, a language spoken in Nigeria, is affiliated with Efik and Oron in the Ibibio‐Efik dialect cluster. The concluding table indicates the tones of pronominal prefixes and verb roots in the various tenses, and gives an example for each tense of an inherent high‐toned monosyllabic verb root.
Unintended consequences: Unlimited access, invisible work and the future of the information profession in cultural heritage organizations

Editor's Summary Information professionals are challenged to deliver simple yet expansive results for the end user, who is typically unaware of increasingly complex systems behind the scenes. Visitors to libraries, museums and archives expect free and unlimited access to resources, but know little of the museum as an information source and the information professional as a service provider, compiling, organizing and delivering the resources of cultural heritage organizations. Changing mindsets are necessitating a change in the ways these organizations interact with visitors, prompting the need for more active engagement with resource users and even collaboration in developing resources. While technological change is fairly easy, sociological change is harder. Information professionals must challenge long traditions and deeply held philosophies to meet public expectations for expanded access to museum resources. But they must also advocate for their own contributions, using socio-technical skills to leverage their work through new platforms and channels to gain broader community recognition, respect and value.
Using big data to map the network organization of the brain.

The past few years have shown a major rise in network analysis of “big data” sets in the social sciences, revealing non-obvious patterns of organization and dynamic principles. We speculate that the dependency dimension – individuality versus sociality – might offer important insights into the dynamics of neurons and neuronal ensembles. Connectomic neural analyses, informed by social network theory, may be helpful in understanding underlying fundamental principles of brain organization.
A contemporary industrial perspective on process control theory and practice

Abstract The chemical process industry, a highly successful global enterprise, currently faces certain challenges having significant implications for Process Control theory and practice. This paper takes the perspective that these challenges actually represent a unique opportunity for Process Technology in general, and Process Control in particular, to make an impact. An overview of some of the most important of these challenges is provided along with some suggestions regarding what the process control community needs to do in order to translate this potential opportunity into actual success.
Quantitative homogenization of elliptic partial differential equations with random oscillatory boundary data

Abstract We study the averaging behavior of nonlinear uniformly elliptic partial differential equations with random Dirichlet or Neumann boundary data oscillating on a small scale. Under conditions on the operator, the data and the random media leading to concentration of measure, we prove an almost sure and local uniform homogenization result with a rate of convergence in probability.
PHOTOCHEMICAL PROPERTIES OF 4-BENZOYLBENZYLAMMONIUM BORATES

Several new 4-benzoylbenzylammonium borates were prepared in order to study their photochemical properties. It was found that a quantitative yield of biphenyl and a small amount of benzene are form...
Replication of vesicular stomatitis virus facilitated in nonpermissive cells by early functions of Shope fibroma virus.

SummaryIn serially cultured domestic rabbit kidney (DRK3) cells, vesicular stomatitis virus (VSV) alone was unable to replicate, inhibit synthesis of cellular DNA, or induce CPE. When these cells were inoculated simultaneously with VSV plus Shope fibroma virus (SFV), both viruses replicated without apparent interference. This faciliation of VSV by SFV also occurred when these dually inoculated cells were treated with hydroxyurea at concentrations which inhibited production of infectious SFV by greater than 99% and synthesis of viral and cellular DNA with a buoyant density in cesium chloride of 1.69 g/cm3 by greater than 90%. These results indicate that an early event in the replication of SFV, before viral DNA synthesis, converts DRK3 cells from a nonpermissive state, in which VSV alone is not even able to induce CPE, to a permissive state that allows complete VSV replication.
The nucleolus organizer region of maize (Zea mays L.): Chromosomal site of DNA complementary to ribosomal RNA

A maize genetic marker strain (designated as the 2NOR strain) was found to carry a cytologically-visible “duplication” of the nucleolar organizer region (NOR). The 2 NOR condition is a simply inherited cytological marker which is transmitted normally through mega- and microsporogenesis and is associated when homozygous with a nucleolus approximately 64% greater in volume than that of two representative normal inbred lines of maize.—Utilizing DNA · rRNA hybridization techniques and the 2 NOR strain plus two unrelated inbred lines with normal NOR's, the chromosomal site of DNA complementary to rRNA was shown to be localized in the NOR. To our knowledge, this is the first report on the localization of rDNA cistrons in the NOR of plants. An estimate was made of 17,000 rDNA cistrons per diploid nucleus for normal maize.—The 2 NOR strain was shown to possess approximately twice as many rDNA cistrons (34,000) as normal maize. The usefulness of this 2 NOR condition for plant protein improvement programs is being investigated.
Ammonia as a precursor in electron-enhanced nitridation of Si(100)

Electron beam-enhanced nitridation of Si(100) using ammonia as a precursor at 110 K was studied with electron-stimulated desorption, XPS, AES and high-resolution electron energy-loss spectroscopy (HREELS). Hydrogen ion kinetic energy distributions from adsorbed ammonia exhibited a component from NH 3 (a) at 7.8 eV, from NH 2 (a) at 5.4 eV and from H(a) at 4 eV. Formation of the nitride following electron beam irradiation of adsorbed ammonia was shown by both N 1s at 398 eV and Si 2p at 102 eV in XPS spectra. From HREELS spectra following electron beam irradiation, we are able to show that the electron beam is highly effective in removal of hydrogen from NH x (a) (x = 3,2) and from the silicon surface. Electron-stimulated desorption of adsorbed hydrogen and dissociation of adsorbed NH x (x = 3,2) are believed to be responsible for enhanced nitridation. Nitride can also form on the surface by irradiating the surface in an ammonia environment at 110 K. A nitride growth rate of 1 A min -1 was obtained from the bulk Si LVV AES signal intensity attenuation.
Elementary school pupils' beliefs about practices for motivating pupils in mathematics

Pupils in the second (N = 304) and fifth grades (N = 272) and their teachers (N = 35) rated the effectiveness of a variety of teacher strategies for motivating pupils to learn maths. Factor analysis indicated that older pupils made finer distinctions among types of strategy than did younger pupils. Second-graders endorsed most strategies, while fifth-graders were more selective, rejecting evaluative praise (e.g., ‘Good boy’), teacher attributions of failure to low effort and of success to high ability. Teachers' ratings differed from pupils' for many strategies; mere were no differences between teachers of second- and fifth-grade pupils. We discuss the implications of these results for the view of pupils as educational theorists, and for teachers wishing to engage pupils in democratic negotiation of classroom practices.
Quantitation of neurochemically identified neurons in reaggregate tissue cultures.

Abstract The study of cellular interactions during the development of the nervous system is facilitated by the use of the reaggregate tissue culture system. In this system, embryonic neurons are dissociated from one another and allowed to reaggregate in rotatory culture, where they resume their normal differentiation. Reaggregates provide a model for studying neuronal development and cell interactions under conditions which allow for the control of a large number of variables, such as the numbers of cells which are allowed to interact, the presence or absence of appropriate target cells, and the chemical environment in which the neurons develop. For quantitative purposes, it is necessary to estimate the numbers of cells of a given neurochemical or morphologic type. Here we describe a computer-assisted counting system which allows one to determine the numbers of neurochemically identified neurons within reaggregate cultures from the counting of such neurons in a randomly selected sample of thirty 10-μm sections from the reaggregates in a given flask. These sections represent less than 0.5% of the total number of sections derived from the reaggregates in a single flask. In addition, the system allows one to quantitatively compare differences in the numbers of such neurons between experimental flasks utilizing appropriate statistical methods. A comparison of the number of central dopaminergic neurons estimated by this method with the direct counting of such neurons in serial sections of single reaggregates resulted in excellent agreement as to the number of dopaminergic neurons within a given experimental flask. The method of assessing and comparing the number of neurons of a given neurochemical type outlined here can be applied to problems of natural cell survival as well as to survival following exposure to a variety of potentially toxic agents.
On some aspects of breakdown of β″-alumina solid electrolyte

A theoretical expression is derived for the pressure generated in the sodium-filled cracks of β″-alumina under electrolytic conditions by treating the flux of sodium ions to the cracks in terms of the Laplace equation for the appropriate boundary conditions. It is demonstrated that the pressure generated decreases with increasing crack length for a given current density in contrast to the predictions of some investigators. It is suggested that some other factors must be considered if the microfracture model via Poiseuille pressure is to be a viable mechanism for electrolyte degradation.
Critical Opalescence in Quartz

The intense scattering of light by quartz in the vicinity of the $\ensuremath{\alpha}\ensuremath{-}\ensuremath{\beta}$ transition, first observed by Iakovlev and co-workers in 1955, has been studied by Raman and Brillouin spectroscopy and by visual observation. Our results indicate that the observed "opalescence" does not originate from critical fluctuations of the order parameter but is generated by essentially static domain walls separating microdomains of opposite electrical twins.
Characteristics of boys' and girls' toys.

In Study 1, 292 undergraduates rated 126 toys as to whether they were suitable for boys, girls, or both. From these ratings, we established five categories of toys: strongly masculine, moderately masculine, neutral, moderately feminine, and strongly feminine. Using these categories, we constructed four toysets; each consisted of 15 toys, three from each category. In Study 2, 706 undergraduates individually rated the toys from one of the toysets on 26 scales that measured the toys' characteristics. We found that girls' toys were associated with physical attractiveness, nurturance, and domestic skill, whereas boys' toys were rated as violent, competitive, exciting, and somewhat dangerous. The toys rated as most likely to be educational and to develop children's physical, cognitive, artistic, and other skills were typically rated as neutral or moderately masculine. We conclude that strongly gender-typed toys appear to be less supportive of optimal development than neutral or moderately gender-typed toys.
Nitrosoarene Complexes of Manganese Porphyrins

p-Amino-substituted nitrosoarenes react with cationic [(T(p/m-X)PP)Mn(THF)2]+ porphyrins to give bis-nitrosoarene adducts. The molecular structure of [(TPP)Mn(ONC6H4NEt2)2]SbF6 has been determined by a single-crystal X-ray crystallographic analysis and reveals a rare O-binding mode of the aryl nitroso ligand.
Monitoring liquid and solid polymers through electroactive response

A variation of dielectric response with deformation, called dielectrostriction, provides a new approach for in-line monitoring properties and structure of materials. The dielectrostriction effect resembles a well-known birefringence phenomenon which has been widely used for NDE of transparent materials. While birefringence is described by the stress-optic rule, the stress-dielectric rule applies to dielectrostriction. However, dielectrostriction measurements can be applied to both transparent and opaque dielectric materials, require a much simpler measurement technique, are capable of measuring local stresses/strains and can be implemented for material processing and health monitoring of structures. Planar capacitor sensor setup is implemented to detect the dielectrostriction effect in both liquid and solid polymers. Dielectrostriction effect and the stress-dielectric relationship are studied for solid polycarbonate subjected to uniaxial tensile load. Similar results are obtained for liquid polymers in oscillatory shear flow.
Droplet Digital™ PCR quantitation of HER2 expression in FFPE breast cancer samples.

The human epidermal growth factor receptor 2 (HER2, also known as erbB2) gene is involved in signal transduction for cell growth and differentiation. It is a cell surface receptor tyrosine kinase and a proto-oncogene. Overexpression of HER2 is of clinical relevance in breast cancer due to its prognostic value correlating elevated expression with worsening clinical outcome. At the same time, HER2 assessment is also of importance because successful anti-tumor treatment with Herceptin is strongly correlated with HER2 overexpression in the tumor (approximately 30% of all breast tumors overexpress HER2). In a comprehensive national study, Wolff et al. [1] state that ‘‘Approximately 20% of current HER2 testing may be inaccurate’’ which underscores the importance of developing more accurate methods to determine HER2 status. Droplet Digital™ PCR (ddPCR™) has the potential to improve upon HER2 measurements due to its ability to quantitate DNA and RNA targets with high precision and accuracy. Here we present a study which investigates whether ddPCR can be used to assess HER2 transcript levels in formalin-fixed paraffin embedded (FFPE) human breast tumors and whether these ddPCR measurements agree with prior assessments of these same samples by pathologists using immunohistochemistry (IHC) and in some cases fluorescence in situ hybridization (FISH). We also determined the copy number of HER2 in these samples as compared to the CEP17 reference gene. Results: Clinical FFPE samples were successfully studied using ddPCR and compared to results from standard FISH and IHC methodology. The results demonstrate that ddPCR can rank order the samples in complete agreement with the current standard methods and that ddPCR has the added benefit of providing quantitative results, rather than relying on the expert skill of a seasoned pathologist for determination.
Vacuum arc metal plasma production and the transition of processing mode from metal ion beam to dc metal plasma immersion

Abstract The vacuum arc provides a straightforward method for the efficient production of dense metal plasma. The plasma so formed can be utilized more-or-less ‘as-is’, or with macroparticle filtering, for the deposition of films of many different kinds. More advanced techniques involve substrate pulse-biasing to achieve a metal plasma immersion processing mode, or the vacuum arc plasma source can be embodied within an ion source configuration for the formation of energetic metal ion beams for carrying out ion implantation. Not inconsequentially, the vacuum arc metal plasma has an innate high ion drift velocity (ion drift speed greater than the ion sound speed), a plasma feature that leads to some novel and important consequences — a negatively-biased substrate located in the plasma stream can maintain unexpectedly high voltages on an essentially dc basis, and an ion source with ‘conventionally poor’ extractor design can provide a kind of plasma immersion ion implantation mode of operation. As the ion source operating parameters are varied, there can in fact be a smooth transition between these two modes — a plasma immersion processing mode and an energetic ion beam processing mode. The metal ion beam mode of operation and the plasma immersion mode of operation are closely related because of the plasma drift. Here, vacuum arc generation of metal plasma is summarized, and a brief review of ion source and plasma immersion modes presented. The significance of high plasma drift as a mechanism that can lead to a dc (or, at least, long-pulse) mode of plasma immersion ion implantation is outlined.
Characterization of Silica-Supported Pd−Au Clusters by X-ray Absorption Spectroscopy

Silica-supported Pd−Au clusters were characterized by Pd K and Au L3 extended X-ray absorption fine structure (EXAFS) spectroscopy and Au L2,3 X-ray absorption near-edge structure (XANES) spectroscopy. Pd−Au/SiO2 catalysts with Pd/Au atomic ratios of approximately 1:1 were prepared by coadsorption of [Pd(NH3)4][NO3]2 and [Au(en)2]Cl3 (en = ethylenediamine) onto silica gel from pH 7 and pH 10 slurries. EXAFS spectroscopy of the Pd−Au/SiO2 (1.3:1, pH 7) catalyst after in situ reduction at 300 °C indicates the formation of bimetallic clusters exhibiting Pd surface enrichment. The EXAFS results can be approximated using a cluster “decoration” model in which a Au-rich core is covered by a partial monolayer of Pd. In contrast, EXAFS spectroscopy of the Pd−Au/SiO2 (1:1, pH 10) catalyst after in situ reduction at 350 °C indicates the formation of homogeneous Pd−Au alloy clusters. The homonuclear bond distances in these clusters agree closely with the Vegard's Law prediction for a 1:1 Pd−Au alloy; however, the het...
Gringita in the Waiting Room: Women's Reproductive Healthcare in Quito, Ecuador

In August of 2008, I embarked on a three-month field research trip to Quito, Ecuador, a project intended to hone my anthropological research skills. The purpose of my trip was to research women's use and perceptions of health care services, paying special attention to the differences between those receiving public and private care. I gained access to seven clinics and hospitals through my participation in a medical volunteer and shadowing program. I had learned of Child Family Health International (CFHI) at the University of Nebraska-Lincoln campus where they were advertising medical volunteering programs all over the world. While the program had locations in developing countries worldwide, I focused on Latin American countries. With the growing Spanish speaking population in the United States, improving my Spanish seemed like a very practical thing to do.
The progression of untreated HIV-1 infection prior to AIDS.

Using a case-control study of untreated men, we investigated the physical, mental, and economic effects of human immunodeficiency virus (HIV-1) infection prior to the diagnosis of acquired immunodeficiency syndrome (AIDS). Beginning 2 to 2.5 years prior to AIDS, case subjects reported more of 12 HIV-1 related symptoms and during the year prior to AIDS, at least 30.6 extra days of these symptoms than did control subjects. Within the 6 months preceding AIDS, case subjects' unemployment rose to 9% (P < or = .05) and depression to 34.2% (P < or = .001). At 6 to 12 months and within 6 months before AIDS, 17.1% and 31.5%, respectively, were anemic, while 37.7% and 64.7% had CD4+ counts less than 200 x 10(6)/L. Diagnosing AIDS at CD4+ counts less than 200 x 10(6)/L could significantly reduce pre-AIDS morbidity. Other implications of these findings are discussed.
Histochemical and electron microscopic observations on "onion bulb" formations in a case of hypertrophic neuritis of 25 years duration with onset in childhood.

Histochemical and electron microscopic data are presented from a patient with hypertrophic neuritis of 25 years duration with onset in childhood. The present observations and those of recent investigators form the basis of a discussion of various pathogenetic hypotheses for “onion bulb” structures in the nerves from patients with hypertrophic neuritis. It is concluded that the onion bulb lesion is a nonspecific manifestation of chronic segmental demyelinization resulting from a primary or acquired abnormality of Schwann cells.
The public context of private medical decisions.

Normative standards powerfully affect the course of our lives. They guide our everyday behavior--how we drive, how we teach our students, how we respond to strangers and intimates. Our expectations about others rely on these standards as well. We assume the actions of people we encounter will fall within a range of appropriate conduct. So much do we take this for granted that we notice it only in the rare instances when our expectations are in error, or when we visit another community or country where the standards are different. In our country, standards of normative conduct permit wider variation than at other times and in other places. We are a pluralistic and diverse nation, and our standards must accommodate this. On many fronts, contemporary U.S. society is struggling to achieve the level of unity and agreement necessary to maintain effective normative standards without unduly suppressing the variety of cultures and individulas that constitute this nation. Normative standards generally operate as unspoken, implicit forces shaping the individual's private thoughts and action. They typically enter the public realm when a perceived breach becomes the subject of informal social sanctions, civil or criminal legal proceedings, media attention, legislative or political activity, or public opinion polls. The standards are constructed at both levels, however. Public pronouncements delineating the standards influence private ideas on the boundaries of acceptable behavior; in turn, private views determine what juries, judges, voters, poll participants, and other players publicly label "beyond the pale." Though by no means problem free, the significant strength of normative standards is their connection to real people negotiating the challenges and responsibilities of everyday life. After the fundamental moral prohibitions are set, normative standards delineate which of the remaining actions should be permitted as reasonable, and which are unacceptably deviant. For a variety of reasons, we have devoted insufficient attention to delineating the normative standards governing administration of life-sustaining treatment. For the most part, the courts, legislatures, and other entities setting policy in this area have sought to minimize public involvement and maximize private discretion in treatment decisionmaking. Accordingly, they speak of the right to privacy, the right to determine without external interference whether to accept the burdens of modern medicine in exchange for a chance at obtaining its benefits. When they do engage in normative standard setting, they disavow this function, claiming instead to ground their decisions in patients' individual preferences. But the goal of keeping quality of life, resource allocation, and other relevant value choices completely at the private level is ill-suited to the contemporary health care environment. …
Thrombophilia testing in patients with venous thrombosis.

Abstract Background Routine thrombophilia testing is controversial because of the low yield of positive tests, costs involved, and debate about the clinical usefulness of the data obtained from testing. Laboratory investigations are rarely done for those with superficial venous thrombosis (SVT) or isolated calf vein thrombosis (CVT) which are often not treated with anticoagulants. Objective To identify the incidence of markers of thrombophilia in patients with deep vein thrombosis (DVT), SVT, isolated CVT or a history of thrombosis in a referral practice. Methods One hundred and sixty-six patients were referred to our thrombosis unit for consultation, including patients with SVT, DVT, and preoperative patients with a previous history of SVT or DVT. Patients underwent thrombophilia screening and patients with a diagnosis of SVT or DVT were confirmed by bilateral duplex ultrasonography of all lower limb veins. Thrombophilia testing included factor V Leiden (FVL), prothrombin 20210A mutation (P2), methylene tetrahydrofolate reductase deficiency (MTHFR), fasting serum homocysteine (HC), lupus anticoagulant (LA), anticardiolipin antibodies (ACA), antithrombin deficiency (AT), protein S deficiency (PS), and protein C deficiency (PC). Results The incidence of any significant abnormality in patients with DVT was 27/44 (61%; 95% Confidence interval [CI], 47–76%) and 10 of these patients were positive for FVL (23%; 95% CI, 10–35%). Twelve patients with isolated CVT were seen and five had at least one abnormality (42%; 95% CI, 14–70%) including one with FVL (8%; 95% CI, 0–24%). Thirty-nine patients with isolated SVT were seen including 14 with at least one abnormality (36%; 95% CI, 21–51%) and five of these patients with SVT had FVL (13%; 95% CI, 2–23%). Nine patients with recurrent DVT were seen and five of these had at least one abnormal test (56%; 95% CI, 23–88%). Finally, 18 of the 166 patients had more than one abnormality (11%; 95% CI, 6–16%). Conclusion The presence of one or more markers of thrombophilia was significantly higher in this patient population compared to reports from other centres. This study identified 18/166 (10.8%; 95% CI, 6–16%) with more than one defect where life-long anticoagulation might be considered. The results in this subset of patients as well as the serious defects found in some patients with provoked DVT, isolated CVT or isolated SVT demonstrate the value of this screening program to both these patients and their blood relatives. On the other hand, this is a small series from a referral practice where the incidence of these defects is greater than one would expect in the general population. These studies are preliminary and it is not recommended that all VTE patients should be screened on the basis of the current report.
Absolute Cross Sections for Single Ionization of Alkali Ions by Electron Impact. I. Description of Apparatus and Li + Results

The absolute cross sections for the single ionization of ${\mathrm{Li}}^{+}$ ions by electron impact have been measured over the electron-energy range from below threshold (75.6 eV) to 800 eV. The measurements were performed with an ultrahigh-vacuum crossed-beam facility operating under continuous, rather than the usual time modulated, beam conditions. A detailed description of the apparatus and experimental method is presented. Numerous checks were performed to justify the use of the continuous-beam measurement technique developed for this experiment, particular attention being paid to beam intensities, beam profiles, space charge, signal-to-noise ratio, and ion-beam composition. The error in the measured cross sections is believed not to exceed \ifmmode\pm\else\textpm\fi{}12% above 150 eV electron energy; it may be as large as \ifmmode\pm\else\textpm\fi{}21% at 90 eV. Of this possible error, an amount \ifmmode\pm\else\textpm\fi{}6% is considered systematic.
Hypothesis testing in event studies: The case of variance changes

Abstract Event study methods to test the effects of financial events on asset returns implicitly assume a stationary variance. Arbitrage theory [Ross (1989)], however, suggests that the variance of returns should change with the flow of information to the market. Empirical evidence confirms this theory—especially as it applies to financial events. In this paper, we develop a new event study test, based on the jackknife methodology, which is robust to changes in information flow during a financial event. We also consider the rank test of Corrado (1989), the sign test of Corrado and Zivney (1992), the generalized sign test of Cowan (1992), the cross-sectional test of Boehmer et al. (1991) and, of course, the standard OLS test. We have constructed a number of experiments to compare the performance of these six tests under four types of variance changes. Although no uniformly most powerful test emerged for all circumstances, our results suggest that if a researcher knows the exact day of the event, then the generalized sign test of Cowan should be applied. However, in most circumstances one must use a multiple-day window to capture the true event day; in this case, we recommend the jackknife test.
Price Dynamics in Limit Order Markets

This article presents a one-tick dynamic model of a limit order market. Agents choose to submit a limit order or a market order depending on the state of the limit order book. Each trader knows that her order will affect the order placement strategies of those who follow and the execution probability of her limit order is endogenous. All traders take this into account which, in equilibrium, generates systematic patterns in transaction prices and order placement strategies even with no asymmetric information. One of the most common ways in which traders exchange securities is in markets based on a limit order book. In a limit order market investors can post price-contingent orders to buy/sell at preset limit prices. Exchanges which operate in this fashion are the Paris Bourse, Tokyo, Toronto, and Sydney. 1 Despite the prevalence of the limit order system, the dynamic aspects of the limit order book have not been well explored. This article presents an explicitly dynamic model of the limit order book in a one-tick market. Traders with different valuations for an asset arrive randomly at a marketplace and trade either immediately by submitting a market
Monitoring global rates of biodiversity change: challenges that arise in meeting the Convention on Biological Diversity (CBD) 2010 goals

By agreeing to strive for ‘a significant reduction in the current rate of loss of biological diversity’ by the year 2010, political leaders at the 2002 World Summit on Sustainable Development (held in Johannesburg, South Africa) presented conservation scientists with a great opportunity, but also one of their most significant challenges. This is an extremely exciting and laudable development, but this reporting process could be made yet more powerful if it incorporates, from the outset, independent scientific assessment of the measures, how they are analysed, and practical ways of plugging key gaps. This input is crucial if the measures are to be widely owned, credible and robust to the vigorous external scrutiny to which they will doubtless be exposed. Assessing how rates of biodiversity loss have changed from current levels by 2010 will require that a given attribute has been measured at least three times; however, most habitats, species, populations and ecosystem services have not been assessed even once. Furthermore, the best data on which to base estimates of biodiversity loss are biased towards the charismatic vertebrate species; unfortunately, these supply minimal services to the human economy. We have to find ways to redress this taxonomic imbalance and expand our analyses to consider the vast diversity of invertebrate, fungal and microbial species that play a role in determining human health and economic welfare. In the first part of this paper I will use examples from local and regional monitoring of biological diversity to examine the desired properties of ‘ideal indicators’. I will then change focus and examine an initial framework that asks how we might monitor changes in the economic goods and services provided by natural ecosystems. I will use this exercise to examine how the set of possible indicators given by the Convention on Biological Diversity might be modified in ways that provide a more critical assay of the economic value of biological diversity. Here I will emphasize that we need not only to monitor these benefits, but also to significantly increase public awareness of human dependence upon the role that non-voting species play in driving the world’s financial economy.
Dislocation Cores and Hardness Polarity of 4H-SiC

The hardness of opposite basal faces of 4H-SiC single crystals has been measured in the temperature range 25°-1200°C. A strong hardness anisotropy between the silicon-terminated (0001) and carbon-terminated (0001) faces of this polar crystal has been found. Transmission electron microscopy investigation of the dislocations in the plastic zone of the 1200°C indentations shows that they lie predominantly on the basal planes parallel to the indented face, and the extra-half planes of the nonscrew dislocations originate from the indented face. It is also found that, when the (0001) Si-terminated face is indented, the dislocations are either widely dissociated, with the width of the stacking fault ribbon much larger than the equilibrium value, or else they are single leading partials, with the corresponding trailing partials absent. In this case, all the leading partials are found to have a silicon core. On the other hand, the dislocations in the plastic zone of the carbon-terminated face are in the form of dissociated dislocations, with the width of the associated stacking fault ribbons appreciably less than the equilibrium value. Moreover, the leading partials of these dissociated dislocations have a carbon core. The results indicate that the hardness of the polar basal faces of 4H-SiC at elevated temperatures is partly determined by the nature of the dislocation cores nucleated by the indentation process. It is argued that this is due to the influence of the core on the generation and glide of the leading partial dislocations.
Effect of a conservative mutation of an active site residue involved in substrate binding on the hydride tunneling reaction catalyzed by choline oxidase.

Abstract The reaction of alcohol oxidation catalyzed by choline oxidase was previously shown to occur through the tunneling of a hydride ion from the α-carbon of an activated alkoxide species to the N(5) atom of FAD within a highly preorganized enzyme-substrate complex [G. Gadda, Biochemistry 47 (2008) 13745–13753]. In the present study, a glutamate residue (312) that participates in substrate binding has been replaced with aspartate by site-directed mutagenesis, and the effect of the substitution on the kinetic parameters of the enzyme and the mechanism of hydride ion transfer were investigated using stopped-flow spectrophotometry. The thermodynamic parameters associated with the enzymatic reaction catalyzed by the mutant enzyme and the temperature dependence of the kinetic isotope effects are consistent with a hydride transfer reaction occurring either through environmentally assisted tunneling or a classical over-the-barrier transition state, but not within a preorganized enzyme-substrate complex. In contrast, less than threefold changes in the Kd values for choline were observed in the mutant enzyme with respect to the wild-type enzyme. Thus, the conservative substitution of an active site residue that is involved in substrate binding, but not directly in catalysis, affects primarily the kred value that reports on catalysis and minimally the Kd value that reports on binding, thereby providing an example of the interplay that these kinetic parameters may have in enzymatic reactions.
OUTBURST DUST PRODUCTION OF COMET 29P/SCHWASSMANN-WACHMANN 1

Multi-aperture photometry of Comet 29P/Schwassmann-Wachmann 1 was conducted on Johnson-Cousins R-band observations spanning 2011 May 1-9 and 2012 June 6-July 3. The comet was observed in outburst on 2011 May 3 and 2012 July 1, during which its brightness increased by 2.2 and 2.1 mag, respectively, as measured through a 10 arcsec aperture. Dust production before and after each outburst is calculated using the parameter Af ρ, which is converted to a lower limit on the dust production rate based on dust models and derived nuclear properties from other studies. Both outbursts are accompanied by large increases in dust production, Af ρ by a factor of ~6.5-7 and dust production rate by a factor of ~18-23. In addition, variations in the dust brightness profile of the coma are examined during the events. The profile is observed to steepen significantly at the beginning of each outburst and then slowly return to pre-outburst values, mirroring the behavior of Af ρ. The start of an outbound ripple of dust in the profile might be observed as the comet returns to its pre-outburst state, although this cannot be confirmed. Using a simple model of the 2011 May 3 outburst, an estimated lower limit of (2.6 ± 0.7) × 108 kg of dust was released during the event. If this is representative of a typical outburst of 29P, then it is estimated that outbursts account for a lower limit of 80 of the total material ejected by the comet per year.
Patents' Effects on Knowledge Asymmetries

Patents have become indispensible for many strategy scholars research efforts as both a theoretical construct and as a means of operationalizing key constructs. Generally, researchers assume that patents act as a disclosure device which reduces manager-shareholder knowledge asymmetries. I, however, examine instances when this may not be so. I argue that the receipt of a patent signal can, in certain instances, reduce outsiders' apparent understandings of a firm's activities. I examine this issue through the lens of the knowledge-based view (KBV) and research in information signaling and bounded rationality. First, I find that a firm's investment in research and development (R&D) elevates the knowledge asymmetry between shareholders and managers. I then find that, on the date of patent filing, the radicalness of a patent positively moderates the R&D-knowledge asymmetry relationship. I also find that on the date of patent filing, a patent's external frequency moderates the R&D-knowledge asymmetry relationsh...
Bidirectional Transepithelial IgG Transport by a Strongly Polarized Basolateral Membrane Fcγ-Receptor

The human MHC class I–related neonatal Fc receptor, hFcRn, mediates bidirectional transport of IgG across mucosal barriers. Here, we find that at steady state hFcRn distributes predominantly to an ...