cssi/SciSciGPT-SciSciNet huggingface dataset:
En route to the vacuole: Tracing the secretory pathway of Toxoplasma gondii

Publisher Summary This chapter focuses mainly on the highly invasive tachyzoite form of the organism with some mention of events in Toxoplasma gondii bradyzoites. While it is a reasonable assumption that specific nutrients needed by the parasite are not available in either the correct form or in sufficient concentration extracellularly to support growth outside cells and that secreted dense granule proteins and the intravacuolar network assist with nutrient acquisition, the understanding of this issue remains limited at best. Secreted dense granule proteins could instead, or in addition, have roles in promoting or blocking antigen processing, in abrogating components of innate host defense mechanisms, or as structural components. By defining the targeting strategies for secreted dense granule proteins, it will now be possible, even in those circumstances where the gene for the endogenous protein cannot be disrupted, to mis-target copies of the endogenous molecule, looking for potential dominant negative effects. Only after this is done will it be possible to propose functions for Toxoplasma proteins at specific locations within the cell.
Langerhans Cell and Interdigitating Dendritic Cell Infection in African Swine Fever

African swine fever (ASF) presently occurs in domestic pigs as a virulent disease, and a moderately virulent disease. The virulent form causes a necrotizing disease and high mortality in 7 to 10 days with negligible immunoglobulin production. The moderately virulent disease does not produce extensive necrosis, has low mortality, and detectable antibody to ASF is produced starting at 6 days post-inoculation (DPI).
Dead Letter Prohibitions and Policy Failures: Applying Government Ethics Standards to Personal Services Contractors

The last two decades have been marked by numerous political efforts to reduce the size of the federal workforce and declare the end of the “era of big government.” These efforts left the federal government strapped for personnel and resources and have forced many agencies to increasingly rely on service contractors in general, and personal services contractors in particular, to fulfill their mandates. According to the Federal Acquisition Regulations, a personal services contract is a contract that creates an employer-employee relationship between the contractor and the federal government. Despite a longstanding — and, arguably, outdated — regulatory prohibition on the use of personal services contracts, many agencies are increasingly employing personal services contractors in positions traditionally reserved for government employees. The result is an absurd situation in which government ethics laws apply differently to service contractors and federal employees who work alongside each other, perform similar discretionary tasks, and have the same potential to engage in corrupt practices. This Note argues that the personal services prohibition represents an outdated and inefficient method of protecting the government’s interest and should be abolished. Given the government’s current reliance on service contractors, procurement officials should not be concerned with whether a contract creates an employment relationship with the government, but instead with whether contractor personnel are being properly managed and supervised. Congress should thus explicitly abolish the personal services prohibition and apply government ethics laws to personal services contractors. This would reduce the ability of personal services contractors, who often perform discretionary functions on the government’s behalf, to act in their own personal interest to the detriment of the government’s mission.
Physiologically-based modeling of monoclonal antibody pharmacokinetics in drug discovery and development

Over the past few decades, monoclonal antibodies (mAbs) have become one of the most important and fastest growing classes of therapeutic molecules, with applications in a wide variety of disease areas. As such, understanding of the determinants of mAb pharmacokinetic (PK) processes (absorption, distribution, metabolism, and elimination) is crucial in developing safe and efficacious therapeutics. In the present review, we discuss the use of physiologically-based pharmacokinetic (PBPK) models as an approach to characterize the in vivo behavior of mAbs, in the context of the key PK processes that should be considered in these models. Additionally, we discuss current and potential future applications of PBPK in the drug discovery and development timeline for mAbs, spanning from identification of potential target molecules to prediction of potential drug-drug interactions. Finally, we conclude with a discussion of currently available PBPK models for mAbs that could be implemented in the drug development process.
Abstract WP543: Apelin Impairs Endothelium-Derived Hyperpolarizing Factor (EDHF)-Induced Relaxation of Cerebral Arteries by Inhibiting Activation of Large Conductance, Calcium-Activated K (BK Ca ) Channels in Vascular Smooth Muscle

Introduction: Apelin is a peptide found in fat cells, endothelial cells and CNS neurons. Apelin levels are increased in conditions linked to cardiovascular disease (e.g. obesity, diabetes). Apelin ...
The Role of Segmental Resection in Crohn’s Colitis

The present chapter examines segmental resection as a surgical option in the treatment of Crohn’s disease of the large bowel. Segmental resection is feasible only if the disease extent is limited, while total abdominal colectomy is more likely associated with multi-segmental or diffuse disease. However, segmental resection and total abdominal colectomy are associated with comparable risk of both overall disease recurrence and surgical recurrence. Most studies have also indicated that the risk of permanent stoma creation is comparable. Therefore, a segmental resection is generally preferable when the extent of disease is limited. In case of concurrent dysplasia the standard of care remains total proctocolectomy with end ileostomy. Either segmental colectomy or total abdominal colectomy are associated with substantial risk of metachronous cancer or dysplasia and should therefore be considered only in individualized circumstances.
School Counseling Intervention Research: A 10-Year Content Analysis of ASCA- and ACA-Affiliated Journals:

Authors performed a content analysis of school counseling–related intervention research in 21 journals affiliated with the American Counseling Association and the American School Counselor Associat...
In-hospital mortality of patients admitted through the emergency department of a comprehensive cancer center.

6125 Background: Cancer is a common presenting condition for emergency departments (EDs); however, there is limited information on outcomes of ED cancer patients subsequently admitted to the hospit...
Drug-induced acute pancreatitis: Prevalence, Causative agents, and Outcomes.

Abstract Background We sought to study the causative drugs, prevalence and outcomes of drug-induced acute pancreatitis (DIAP). Methods Retrospective study of DIAP patients at a tertiary teaching hospital. The diagnosis and severity of pancreatitis were determined based on the Revised Atlanta Classification. The cases were further subclassified using the Badalov et al., 2008 classification, and Naranjo score to evaluate and determine the odds of drug-related adverse reaction as a causative factor for AP. Results Out of 841 AP patients, a total of 31 patients (3.6%) with DIAP were included. The mean age was 52.9 years, 51.6% were male. The most common causative drugs are listed in Table 3. Most cases were mild in severity (87%), moderate AP occurred in 2 patients (6.5%) and severe AP in 2 patients (6.5%). 19.3% had systemic inflammatory response syndrome at presentation, but it persisted beyond 48 h in only 9.6%. 9.6% developed acute kidney injury. One patient with valproate induced DIAP had pancreatic necrosis, splenic vein thrombus, and sub occlusive superior mesenteric vein thrombus on abdominal imaging. Three patients had recurrent AP, and two (6.5%) of them eventually developed chronic pancreatitis. Notably, none of our patients developed complications such as shock, acute respiratory distress syndrome, bacteremia, or death. 1 patient had an acute peripancreatic fluid collection on initial imaging and another patient developed a pseudocyst on follow up imaging. None of them required drainage. Conclusion Our study showed a prevalence of DIAP of (3.6%) and hydrochlorothiazide, azathioprine, and doxycycline were the most common culprit drugs.
Una exploración de la novela urbana del Caribe colombiano: Cosme y la crisis de la sociedad tradicional barranquillera

La novela Cosme (1927), del escritor barranquillero Jose Felix Fuenmayor (1885-1966), es quizas una de las manifestaciones narrativas mas importantes de la tradicion literaria del Caribe colombiano. Este trabajo busca exponer como el escenario narrativo de su novela urbana permite entrever la formacion de nuevas configuraciones sociales e ideologicas que senalan la crisis y el decaimiento del sujeto tradicional Caribecolombiano y la fundacion de un nuevo momento historico.
The Effect of Sonophoresis on Topical Anesthesia: A Pilot Project

The dental anesthesia sonophoresis device (DASD) is a novel device that is intended to reduce the discomfort associated with intraoral mucosa needle puncture. The DASD produces ultrasonic energy that provides a sonophoretic effect on the oral mucosa, generating microchannels through the lipids between the keratinized cells that make up the stratum corneum. Once the topical anesthetic has permeated the stratum corneum, it quickly diffuses through the soft tissue, desensitizing the nerve endings and reducing the perception of pain caused by needle penetration. The aim of this study is to evaluate whether topical anesthesia applied using the DASD will reduce the discomfort of the needle puncture when compared to the control device. A split-mouth model, using 50 healthy subjects with puncture site at the maxillary canine vestibule, was used for this study. Subjects received a needle puncture on both sides of the mouth. Prior to the needle puncture, there was randomized application of 5% lidocaine with the DASD and a control device. Subjects rated their discomfort after needle punctures utilizing the visual analog scale pain scoring system. There was no statistically significant difference in the pain perception using the DASD versus the control device.
An optimized surface aerodynamic temperature approach to estimate maize sensible heat flux and evapotranspiration

Abstract Typical errors for single-source sensible heat flux estimation models range from 15-40% for vegetated surfaces, with 10 to 20% errors introduced by atmosphere stability functions and remaining errors due to the quality of the input data and assumptions regarding the surface aerodynamic temperature (To). This paper describes the development and evaluation of an optimized To model, which serves as key input to estimate and improve sensible heat fluxes for maize fields. The best resulting optimized linear model included four variables: air temperature, surface temperature, fractional vegetation cover, and a proposed new variable that accounts for wind speed and the relative angle of attack between wind direction and crop row orientation. During the 2017 to 2019 maize growing seasons, on two different fields located at a Research Farm near Greeley, Colorado, USA, field data were collected. Micrometeorological data were measured in situ at the height of 3.30 m above the ground surface. Nadir-looking stationary infrared thermometers measured surface temperature. Multispectral surface reflectance data were collected on-site weekly using a handheld multispectral radiometer. Net radiation and soil heat fluxes were acquired at approximately ¼ and ½ of the field's length. Sensible heat fluxes were measured with two sets of Large Aperture Scintillometers to calibrate the To model. A one-way Analysis of Variance was performed to model To for different ranges of maize leaf area index values. A local sensitivity analysis was performed to identify the most influential explanatory variables in the To optimization model. The sensitivity analysis indicated that uncertainty on air temperature and surface temperature measurements were responsible for the most variability in sensible heat flux estimates when using the developed optimized To model. Overall, results indicated that the optimized To model improved the estimation of maize sensible heat fluxes by 31%; which resulted in an improvement on latent heat flux (or evapotranspiration) by 9% compared to a non-optimized linear To model. The interactions between the crop row layout and wind direction promote more turbulent mixing for heat transfer mechanisms.
Reports from Science Mount St. Helens

The following reports describe extensive measurements of the properties of the gases and aerosols (particles) in the volcanic clouds produced by the eruptions of Mount St. Helens from March through August 1980. Volcanic material was first injected into the atmosphere on 27 March 1980. This material, as well as that introduced by subsequent eruptions during the next 2 months, was confined to the troposphere. On 18 May the first of several major explosions occurred in which some of the volcanic cloud penetrated well into the stratosphere. The nature of the volcanic activity at Mount St. Helens from the end of March through June was described.
Measurements of Point Source Sensitivity of Three High Gain Camera Tubes

Publisher Summary This chapter describes the measurements of point source sensitivity of three high gain camera tubes. Several types of high sensitivity camera tubes have been developed that incorporate prescanning gain to overcome the internal noise of the scanning beam or of the preamplifier. The dynamic detection characteristics have been studied and measurements on moving point sources are reported. The background noise limit is a very significant parameter of a camera tube used for the point source detection in the presence of a high background flux density. The fluctuations or noise in the background also follow Poisson statistics, and therefore, the background noise increases as the square root of the number of photoelectrons integrated per resolution element. The RCA type C2114B has a pad type target in which conductive pads have been deposited upon the p-type islands to provide good beam acceptance and to minimize the area of silicon dioxide that is exposed to the electron beam. It is found that the video representation of the point source appears on more than one line, as each target resolution element is scanned by approximately two or three lines.
ESR Studies on Cation Radicals of Saturated Hydrocarbons

The most prominent development in the study of cation radicals by electron spin resonance (esr) during the past 20 years is the detection and the structural study of alkane cation radicals[1,2]. Although an olefin cation was detected by Ichikawa and Ludwig by the radiolysis of tetramethylethylene(TME) in an inert alkane with an electron scavenger[3], detection of alkane cations had been unsuccessful despite many efforts such as irradiation of alkanes at 4 K with or without an electron scavenger[4]. As a consequence, alkane cations had been thought to be unstable and decomposed by the instantaneous deprotonation. Nauwelaerts and Ceulemans applied the technique similar to that of Ichikawa to an alkane system and reported the spectrum of “n-C8H18 +”. However, it was too obscure to identify the radical as an alkane cation[5]. In 1979, Smith and Symons obtained the esr spectrum of the hexamethylethane cation radical (HME+) as the first example of an alkane cation radical, by the radiolysis of HME in CBr4 or CC14[6]. This result was, however, not sufficient to be accepted by the general researcher, although its assignment was supported by the subsequent work by Wang and Williams[7] and later by Shida et al. using Freons as the matrices[8]. It was the work by Iwasaki and his coworkers on C2H6 + in SF6 at 4 K, published in 1981, that gave a definite proof for the detection of the alkane cation radical with clear information on the structure of it[9].
Theories in Second Language Acquisition: An Introduction

This edited collection brings together an overview of two historical and nine contemporary theories in second language acquisition (SLA). Unlike many introductory SLA textbooks, this volume feature...
Ultrafast lasers and X-ray applications

Summary form only given. The rapid evolution of femtosecond laser technology has led to the generation of multiterawatt optical pulses at multi-Hertz repetition rates with pulse durations as short as 16 fs. The combination of high repetition and high peak power lends itself naturally to the generation of high fluxes of energetic particles and photons. Furthermore, X-rays generated with these pulses can have pulse durations which are several orders of magnitude shorter than the best synchrotron sources currently available. More importantly their time-scale (1 ps to <100 fs) is commensurate with that of many interesting physical phenomena including: the making and breaking of chemical bonds, the expansion of instantaneously heated lattices, optical phonon generation and propagation of laser induced shocks, etc. In this presentation, the development of 10-fs-range laser technology and ultrafast X-ray sources and applications will be presented. With these technologies it has been possible to generate picosecond X-ray movies of laser heated crystalline materials which show for the first time the propagation of coherent acoustic phonons into bulk material with milliangstrom strain resolution and picosecond temporal resolution. Extensions and possible future applications and sources will be outlined.
Dynamic poverty experiences and development of overweight in a prospective cohort of US children aged 4-14 years.

Objective To examine the associations between poverty dynamics and the long-term risk of developing overweight or obesity. Design and Methods Our data are a representative sample of US children from the National Longitudinal Survey of Youth 1979 Child and Young Adult Survey (1986-2008). We used survival analysis to compare risk of developing overweight or obesity among 5,613 children aged 4-14 years from never poor households, transient poor households (those that became poor only once), recurrent poor households (those that became poor more than once), and persistent poor households (those that became poor and remained poor for at least 4 consecutive years) and examined interactions by race/ethnicity, gender, and age. Results Compared with children from never poor households, children from transient poor households (HR 0.79, 95% CI: 0.68-0.92), recurrent poor households (HR: 0.73, 95% CI: 0.62-0.87), and persistently poor households (HR: 0.62, 95% CI: 0.51-0.74) had significantly reduced risks of becoming overweight or obese. These associations did not vary by race/ethnicity, gender, or age. Conclusions Our findings suggest that poverty experiences are associated with reduced risk of becoming overweight or obese among children of 4-14 years.
Self-assessment of professionalism in physical therapy education.

Objective With the physical therapy (PT) professions' advancement to the clinical doctorate degree and the promotion of autonomous practice, exemplary professional conduct is an expectation of the PT profession. PT education programs are being challenged to develop methods to teach and assess professional behavior. Participants Forty-three PT students (11 male and 32 female, ages 20-28 years) completed the APTA Professionalism in Physical Therapy: Core Values Self-Assessment (PPTCVSA) after their first 3 week clinical experience and again after their final clinical experience. Methods A mixed design ANOVA compared participants' total scores and individual Core Value scores on the Professionalism in Physical Therapy: Core Values Self-Assessment (PPTCVSA) after 3 and 33 weeks of clinical education. The effects of gender, age, and undergraduate area of study on growth in professionalism scores were also investigated. Results Total PPTCVSA scores and individual Core Value scores on professionalism (accountability, altruism, compassion/caring, excellence, integrity, professional duty, and social responsibility) were higher after 33 weeks compared to scores after 3 weeks of clinical education. Female student's total professionalism scores were higher than male student's scores on both the first and second self-assessments. In addition, female students scored themselves higher than their male peers on accountability, excellence, integrity, and professional duty. Conclusions Improved scores on the PPTCVSA indicate that physical therapy education is playing an important role in the development of professional behavior, knowledge, and application in practice.
Intra-system interconnects for digital communications

The electrical performance of three types of cables, namely coaxial, shielded ribbon and flexible-film is characterized for interconnection applications inside high-speed digital systems. Measurements are made of the cable attenuation signal propagation integrity, bit-error rate, connector discontinuities and crosstalk. The electrical parameters obtained experimentally are used in simulations to predict the bandwidth and range of useful lengths for these cables. The paper highlights the performance-limiting factors such as connector and via discontinuities, and printed-circuit-board wiring losses and the practical density and extendibility limitations are discussed. >
On the stability of third-order sigma-delta modulation

The geometric methods introduced in H. Wong, 'A geometric view of /spl Sigma/-/spl Delta/ modulation,' IEEE Trans. Circ. Sys., Vol. 39, no. 6, pp. 402-405, are applied to the basic architecture of third-order, single-path sigma-delta modulation. An attempt is made to answer the fundamental questions on the stability problem of the third-order system, i.e., can such a modulation be stable, and if so, under what conditions? Combined with the application of bifurcation theory, the stability and other dynamical properties of the modulation are revealed, and certain guidelines directly applicable to the design are provided. >
Testing change in volatility using panel data

The focus of this paper is to test the possible changes in the volatility of panel data. The test statistic is derived from a likelihood argument and it is based on the CUSUM method. Asymptotic distribution is derived under the no change null hypothesis and the consistency of the test is also established. Monte Carlo simulation shows the effectiveness and improvement of the proposed procedure over some of the existing testing procedures.
The Paradoxical Impact of Corporate Inversions on US Tax Revenue

Corporate inversions – reorganizations that result in relocating corporate tax domiciles from the US to a foreign country – are alleged to cost the US Treasury billions of dollars in tax revenue. Contrary to these assertions, we find that that inverting firms pay no less taxes after the inversion than they did before. Moreover, contrary to the common belief, we estimate that the inversions result in US shareholders realizing $81,415.92 million in capital gains and annual increases in dividends of $9,959.37 million. Thus, paradoxically, inversions are likely to increase tax collections by the US Treasury.
Neurofibromatosis type 1: brain stem tumours.

We describe the clinical and imaging findings of brain stem tumours in patients with neurofibromatosis type 1 (NF1). The NF1 patients imaged between January 1984 and January 1996 were reviewed and 25 patients were identified with a brain stem tumour. Clinical, radiographical and pathological results were obtained by review of records and images. Brain stem tumour identification occurred much later than the clinical diagnosis of NF1. Medullary enlargement was most frequent (68 %), followed by pontine (52 %) and midbrain enlargement (44 %). Patients were further subdivided into those with diffuse (12 patients) and those with focal (13 patients) tumours. Treatment for hydrocephalus was required in 67 % of the first group and only 15 % of the second group. Surgery was performed in four patients and revealed fibrillary astrocytomas, one of which progressed to an anaplastic astrocytoma. In 40 % of patients both brain stem and optic pathway tumours were present. The biological behaviour of brain stem tumours in NF1 is unknown. Diffuse tumours in the patients with NF1 appear to have a much more favourable prognosis than patients with similar tumours without neurofibromatosis type 1.
Photochemically-driven biomimetic oxidation of alkanes and olefins

Abstract Photochemical oxidation of hydrocarbons using molecular oxygen as oxidant and Sn(IV)-or Sb(V)-porphyrin as photosensitizer to generate the required co-reductant is described. Fe(III)- or Mn(III)-porphyrin is the hydrocarbon-oxidation catalyst. The system is long-lived and may be used in photo-initiated spectroscopic kinetic studies.
Relative toxicities and neuromuscular nicotinic receptor agonistic potencies of anabasine enantiomers and anabaseine.

Anabasine occurring in wild tree tobacco (Nicotiana glauca) and anabaseine occurring in certain animal venoms are nicotinic receptor agonist toxins. Anabasine lacks the imine double bond of anabaseine; the two possible enantiomers of anabasine occur in N. glauca. A comparision of the relative potencies of S- and R-anabasine has not been previously reported. We separated the enantiomers of anabasine by reaction of the racemic N. glauca natural product with 9-fluorenylmethoxycarbonyl-L-alanine (Fmoc-L-Ala-OH) to give diastereomers, which were separated by preparative reversed phase HPLC. The S- and R-anabasine enantiomer fractions were then obtained by Edman degradation. A mouse bioassay was used to determine the relative lethalities of S- and R-enriched anabasine enantiomers. The intravenous LD50 of the (+)-R-anabasine rich fraction was 11± 1.0 mg/kg and that of the (−)-S-anabasine-rich fraction was 16±1.0 mg/kg. The LD50 of anabaseine was 0.58±0.05 mg/kg. Anabaseine was significantly more toxic in the mouse bioassay than S-anabasine (27-fold) and R-anabasine (18-fold). The relative agonistic potencies of these three alkaloids on human fetal nicotinic neuromuscular receptors were of the same rank order: anabaseine ≫R-anabasineNS-anabasine. © 2006 Published by Elsevier Inc.
Experimental chronic cerebrovascular spasm in the monkey: An assessment of the functional changes in the cerebral arteries and their protection by diltiazem

Abstract The structure and function of cerebral arteries obtained from a monkey model of chronic cerebral vascular spasm 5 days after hemorrhage have been examined. Narrowing of the larger cerebral arteries demonstrated by angiography at all sites of measurement seems to be due primarily to an increased wall rigidity associated with cellular damage, the resultant inflammatory response and large, long-lasting spontaneous increases in muscle tone. Changes in agonist sensitivity were extremely variable. The reduction of contractility of the vessel wall to a mean of 30% of control diminished the consequence of any changes in active tone characteristics. Neurogenic control on the side of the lesion was remarkably depressed. When treated with diltiazem, beginning 1 day before induction of hemorrhage and continuing to the time of sacrifice, arterial diameter was reduced at only 1 of the 6 standard sites of measurement and then by only a small amount. Neurologic effects invariably seen in the untreated monkeys were prevented by diltiazem. Many of the changes in the artery wall, including structural alterations, were diminished by the drug. Abnormal spontaneous myogenic tone was present but was less in the diltiazem-treated group; however, nerve damage and its functional consequences were not prevented. It is concluded that diltiazem, presumably by preventing the accumulation of intracellular calcium within the cell, prevents the initial events in the evolution of chronic cerebrovasospasm or narrowing. This is probably achieved by a diminishing of the direct vasoconstrictor effects and the toxicity of putative spasmogens released from blood clots, nerves and the brain on the vascular smooth muscle, thus interrupting the sequence leading to pathologic change.
Bank debt and financial flexibility

We empirically examine the impact of the need for financial flexibility on firms' use of bank debt. Using a comprehensive sample from capital IQ (CIQ), we find that firms that are more likely to violate a covenant or incur higher costs from a covenant violation use less bank debt. Our results persist for both bank drawn revolving lines and term loans and for firms with or without access to the public bond market. These findings provide strong support to the survey results of Graham and Harvey (2001) that financial flexibility is an important factor in shaping corporate debt policy.
Realism, Empiricism and Social Constructionism Psychological Theory and the Social Dimensions of Mind and Action

This article attempts to characterize scientific realism as a viable alternative metatheory for psychological science that is superior to traditional empiricism. It is suggested that scientific realism provides a richer conception of psychological theory than traditional empiricism, and enables the theoretical psychologist to acknowledge the respects in which human actions and psychological states may be said to be social in nature, without abandoning the traditional scientific virtues of linguistic and epistemological objectivity that have been rejected by social constructionist and relativist theorists.
A method for measuring strains in soft tissue

A finite element based method has been developed for measuring strains in soft tissue. An array of markers is placed on the tissue surface and treated as nodes of a four node isoparametric element. The displacements of the marker centroids are directly measured using a high sensitivity television camera. Finite element method mathematics are then used to calculate the plane strain tensor at any point inside the element. The method has been implemented using non-rectangular elements that are approximately 2 mm on each side.
Product and project challenges in electronic commerce software development

Electronic commerce (E-commerce) software development organizations face unique challenges based on rapidly changing markets, demanding customers with ill-defined requirements, and resulting priority conflicts between product line development and customer projects. A model of this unique development environment is identified with important linkages among the product function, the project function, and the underlying software development function within an organization. Guided by this model of the E-commerce development environment, a case study of a medium-sized E-commerce company was conducted. Based on this study, eight critical challenges to the successful development of top quality software systems are identified. From these challenges a research model and propositions are presented. As each challenge is discussed unique impacts of the E-commerce environment are reinforced by direct quotes from in-depth interviews. On-going research will draw upon the research model and propositions to provide insights on how best to develop software products and deliver customer projects in E-commerce environments.
Optical evaluation methods in particle image velocimetry

Abstract Application of particle image velocimetry (PIV) techniques for measurement of fluid velocities typically requires two steps. The first of these is the photography step, in which two exposures of a particle field, displaced between the exposures, are taken. The second step is the evaluation of the double-exposure particle pattern and production of appropriate particle velocities. Each of these steps involves optimization, which is usually specific to the experiment being conducted, and there is significant interaction between photographic parameters and evaluation characteristics. This paper will focus on the latter step, that of evaluation of the double-exposure photograph. In several parts of a PIV system, some performance advantage may be obtained by increasing use of optical processing over conventional digital image processing. Among the processes for which a performance advantage may be obtained are parallel or multiplex image interrogation and the evaluation of the Young's fringe pattern obtained from the scattered pattern from the double-exposure photograph. This paper will discuss parallel image interrogation and compare the performance of optical and numerical Fourier transform analysis of Young's fringes using speckle images.
Understanding waveguiding in vertical-cavity surface-emitting lasers

Summary form only given. We present the first theoretical treatment of waveguiding in VCSELs that properly includes the effects of the resonant cavity. The resulting treatment immediately suggests new designs for leaky-mode (antiguided) VCSELs that should result in devices operating in the fundamental mode to powers much higher than presently attainable.
Dysplasia epiphysialis multiplex.

Summary A case of dysplasia epiphysialis multiplex in a 6-year-old male child is recorded. There is no specific etiologic factor responsible for this syndrome. The irregularity of the epiphysial outline combined with stippling is a distinguishing diagnostic feature which is observed in multiple bones. The ultimate prognosis is for a spontaneous recovery from the symptoms and for a restoration of normal function. Some roentgenologic findings may persist after many years. Treatment does not influence the course or ultimate outcome of this condition.
The metabolism of 3,4-dichloropropionanilide in plants. Partial purification and properties of an aryl acylamidase from rice

Abstract An aryl acylamidase (aryl-acylamine amidohydrolase, EC 3.5.1.a) from rice, which hydrolyzes 3,4-dichloropropionanilide, has been partially purified and characterized. The distribution of the enzyme in rice and barnyard grass tissues was determined. The enzyme displayed a broad specificity for chlorinated ring-substituted propionanilide analogs, but was specific for 3,4-dichloropropionanalide when compared with several alkyl substituted analogs. The enzyme was inhibited by sulfhydryl reagents and was strongly inhibited at 1·0 × 10 −6 M by the insecticidal carbamates 1-naphthylmethylcarbamate,4-benzothienyl methylcarbamate, 2-chloro-4,5-xylyl methylcarbamate, 2,4,5-trimethylphenyl methylcarbamate, 3,4,5-trimethylphenyl methylcarbamate and 4-(methylthiol) 3,5-xylyl methylcarbamate. The partially purified enzyme had a broad pH optimum between 7·5 and 7·9, with an apparent K m of 2·93 × 10 −3 M for 3,4-dichloropropionanilide. The K i for 1-naphthyl methylcarbamate was 1·51 × 10 −8 M with 3,4-dichloropropionanilide as the substrate. The significance of the enzyme distribution in the resistant and susceptible species and the inhibition of the rice enzyme by insecticidal carbamates is discussed.
Echinococcus granulosus: Acute systemic allergic reactions to hydatid cyst fluid in infected sheep

Abstract Sheep with naturally acquired infections of Echinococcus granulous and uninfected sheep were injected intravenously with hydatid cyst fluid, and the clinical, cardiopulmonary, hematological, and pathological effects were recorded. The clinical response of infected sheep was severe, and one animal died. Cardiopulmonary changes included a “triple response” of the systemic blood pressure ending in prolonged hypotension and pulmonary arterial and intrapleural hypertension. An immediate, severe neutropenia was followed by a rebound neutrophilia and eosinophilia. Packed cell volume and plasma protein concentration were increased, and coagulation time was prolonged. Pathological changes, confined to the lungs, consisted of congestion, periarteriolar and peribronchiolar hemorrhage, edema, and sequestration of polymorphonuclear cells in the alveolar capillaries. The clinical signs after injection were mild or absent in noninfected sheep. The initial changes in systemeic and pulmonary pressures were similar to those in the infected animals; however, these pressures reverted to preinjection levels by 5 min after injection. The neutrophil response in control animals was identical to that in infected animals, and three control animals had a marked eosinophilia at 24 hr. Pathological changes were less marked in the noninfected animals. The responses of hydatid-infected sheep to hydatid fluid injection suggest anaphylaxis because of their similarity to the manifestations of experimental anaphylaxis in sheep and other ungulates. Although there were statistically significant differences in the responses of infected and noninfected sheep, they were differences in degree rather than kind. Two control sheep were infected with single cysticerci of Taenia hydatigena , and this related larval cestode may have produced sensitization to E. granulosus antigens. The mechanism of the reactions occurring in sheep neither infected with T. hydatigena nor with demonstrable agglutinating antibody to E. granulosus antigens is unknown. These reactions may be manifestations of the primary toxicity of hydatid cyst fluid; however, that sensitization to unknown antigens could have produced cross-reactivity to E. granulosus antigens remains a possibility.
Does cardiopulmonary bypass temperature correlate with postoperative central nervous system dysfunction

A National Institutes of Health-funded trial of perfusate temperature and neurological function was begun in the Baystate Medical Center in February 1994. It randomizes patients having coronary revascularization to three temperatures--warm (37 degrees C), tepid (32 degrees C), and cold (20 degrees C)--for systemic perfusate and blood cardioplegia temperature at 37 degrees C warm, 32 degrees C tepid, and 6 degrees C to 10 degrees C cold. The goal is to have a quantitated neurological examination performed prior to operation, prior to discharge at day 3 or 4, and at a 1-month follow-up interval. The initial 51 patients completing a 1-month follow-up broke down to 14 cold, 22 tepid, and 15 warm. The neurological examination quantitated their performance on the Mathew Scale, an ordinal measure from 1 to 100, with 100 being normal. There was a significant (p < 0.05) decrease across the entire study from preoperative to postoperative that was no longer present at late follow-up. Although the lowest mean scores (94.8) occurred in the warm group, they were not statistically different from the other groups', and there was no discernible influence of temperature on neurological function. Additional patients will be entered to validate a difference if such exists.
The dilemma of discontinuation of anticoagulation therapy for patients with intracranial hemorrhage and mechanical heart valves

Background Anticoagulant-related hemorrhage occurs with an incidence of approximately 1%/patient-year in mechanical heart valve recipients. Intracranial hemorrhage poses a difficult clinical choice; continuing anticoagulation therapy may enlarge the volume of the hemorrhage, early reinstitution of anticoagulation therapy may predispose patients to recurrence, and reversal of anticoagulation therapy may place patients at risk for systemic embolization involving the brain. The risk of embolization may also be greater for patients with atrial fibrillation, cage-ball valves in the mitral position, and reduced ventricular function. This dilemma exists because of a lack of data for a large series of patients. Methods We reviewed the medical records and neuroimaging studies for a consecutive group of patients admitted with intracranial hemorrhage and mechanical heart valves. We reviewed neurological presenting data, cardiac risk factors for systemic embolization (atrial fibrillation, enlarged atrial chambers, reduced ventricular function, and the type and location of the metallic valve), and hospital management. Results We studied 39 patients with intracranial hemorrhage and mechanical heart valves (median age, 69 yr). Four patients had experienced previous transient ischemic attacks or minor strokes. The time from valve replacement to intracranial hemorrhage ranged from 2 months to 19 years (median, 6 yr). The type of intracranial hemorrhage was acute subdural hematoma (n = 20), lobar hematoma (n = 10), subarachnoid hemorrhage (n = 4), cerebellar hematoma (n = 3), or basal ganglionic hematoma (n = 2). Thirteen patients died within 2 days of admission. All 26 surviving patients received fresh frozen plasma and vitamin K. Fifteen patients underwent evacuation of acute subdural hematoma, and in one patient an anterior communicating aneurysm was clipped. The duration of discontinuation of anticoagulation therapy varied from 2 days to 3 months (median, 8 d). None of the patients developed transient ischemic attacks, ischemic strokes, valve thrombosis, or systemic embolization. No recurrence of intracranial hemorrhaging was observed during hospitalization and reinstitution of anticoagulation or antiplatelet agent administration. Conclusion Temporary interruption of anticoagulation therapy seems safe for patients with intracranial hemorrhage and mechanical heart valves but without previous evidence of systemic embolization. For most patients, discontinuation for 1 to 2 weeks should be sufficient to observe the evolution of a parenchymal hematoma, to clip or coil a ruptured aneurysm, or to evacuate an acute subdural hematoma.
Beyond objects: a response

In a recent article [5], Shaw puts forth the argument that a process control paradigm for structuring software is more natural, and hence most appropriate for process control applications. However, we believe that there are other considerations, such as scalability and maintainability, that need to be addressed when choosing a design paradigm. Our experience, and a re-examination of Shaw's models, suggests that object modeling is more appropriate for large scale process control applications.
Regional brain glutamate transport in rats at normal and raised concentrations of circulating glutamate.

the permeability of the blood-brain barrier to glutamate was measured by quantitative autoradiography in brains of control rats (average plasma glutamate concentration of 95 μ) and rats infused with glutamate (average plasma glutamate concentration of 837 μm). Measurements of glutamate permeability were initiated by the injection of [14C]glutamate and stopped at 1 min to avoid the accumulation of [14C]glutamate metabolites. Glutamate entered the brain at a slow rate, with an average permeability-surface area product of 7 μl.min...g-1, except in those areas known to have fenestrated capillaries. Glutamate accumulated in the choroid plexus of ventricles, but did not seem to enter the cerebrospinal fluid in detectable amounts regardless of the circulating concentration. Glutamate accumulated in circumventricular organs, such as the median eminence, where the radioactivity was localized without detectable spread. Infusion of glutamate to create high plasma concentrations did not result in greater spread of [14C]glutamate beyond the immediate vicinity of the circum ventricular organs.
An experimental facility for cooperative processing in APL

The Cooperative Processing Facility was designed to allow cooperation between active workspaces on a host and a workstation. This facility consists of two auxiliary processors on each system. When a workstation is connected to a host system by an appropriate emulator, this facility enables an APL user on the workstation easily to develop the application giving access to the active workspace of the host APL system. A prototype was developed for APL2 and Japanese APL, and its effectiveness was verified by implementing it experimentally.
Separate mechanisms for cellular uptake of purine nucleotides by B- and T-lymphoblasts.

Cultured B- and T-lymphocytes have multiple plasma membrane enzymes capable of cleaving extracellular phosphate-containing molecules. These enzymes include a specific 5′-nucleotidase (5′-N, EC 3.1.3.5) whose substrates are primarily purine 5′-nucleoside monophosphates and non-specific phosphatase(s) (NS-phos, EC 3.1.3.1) which has (have) questionable phosphorolytic activity for purine compounds under physiologic conditions. In a tissue culture system, 2 B-cell and 2 T-cell lines were compared for I control growth or killing in the presence of 2 members of the cytotoxic 6-mercaptopurine family:6-MPR (nucleoside) and 6-MPRP (nucleotide).
Kinetic competition during glass formation

For vitrification of an alloy melt during cooling there is a kinetic competition with the nucleation and growth of metastable and stable crystalline phases. Many of the measures of glass forming ability (GFA) attempt to capture some of the features of the kinetic competition, but the GFA metrics are static measures and the kinetic processes are dynamic in nature. In fact, the critical cooling rate for glass formation should be viewed in terms of a critical cooling rate range to acknowledge the stochastic nature of crystal nucleation behavior. Direct measurements of the critical cooling rate range confirm this behavior and also provide useful input for kinetics analysis. Usually kinetics analyses are based upon crystallization behavior that is measured either isothermally or upon heating to temperatures near the crystallization onset, Tx and the results are extrapolated to much higher temperatures. This practice is based upon a number of assumptions about transport behavior in the undercooled liquid. With rapid up-quenching of amorphous samples, the high temperature crystallization behavior can be measured and used to refine the kinetics analysis and provide useful insight on the kinetic competition and glass forming ability.
Alkyl substituted 2,2'-diquinolines and alteration of their spectrophotometric constants following copper (I) chelation

Abstract A study has been made of 10 substituted 2,2'-diquinolines together with their physical constants involving maximum and minimum wavelengths of absorption and associated molecular extinction coefficients. An attempt has been made to interpret the results in relation to the π-electron distribution brought about by substitution of methyl or phenyl groups for hydrogen. The known proficiency of the phenyl groups as an electron donor as compared with the lesser tendency provided by the methyl alkyl group, previously clearly shown in the case of similar substitutions in 1,10-phenanthroline, has been found to apply in the case of 2,2'-diquinoline. The study of mono- and di-substitutions in the 3,4- and 4,4'-positions in 2.2'-diquinoline have been included. It is thought that a better understanding has been attained of the factors influencing structural modifications in the parent molecule which would be worthy of consideration in the case of future attempted developments. The most efficient diquinoline yet described, namely, 4,4'-diphenyl-2,2'-diquinoline (molecular extinction coefficient 9020, wavelength of maximum absorption 559 mμ), was obtained following the disclosed principles of structure.
Acoustic waves in gases with strong pressure gradients

The effect of strong pressure gradients on the acoustic modes (standing waves) of a rectangular cavity is investigated analytically. When the cavity response is represented by a sum of modes, each mode is found to have two resonant frequencies. The lower frequency is near the Viaesaela-Brundt frequency, which characterizes the buoyant effect, and the higher frequency is above the ordinary acoustic resonance frequency. This finding shows that the propagation velocity of the acoustic waves is increased due to the pressure gradient effect.