cssi/SciSciGPT-SciSciNet huggingface dataset:
Dynamics of the near-earth magnetotail - Recent observations

Observations relevant to models of the magnetotail and its ionospheric coupling are presented. Particular attention is given to the near-earth plasma sheet and magnetotail lobes. Plasmoid formation in the near-earth plasma sheet is examined in the context of new measurements of auroral oval motions and of plasma convection near the center plane of the plasma sheet.
Dynamic thresholding for automated analysis of bobbin probe eddy current data

An automated algorithm is presented for the analysis and classification of eddy current bobbin probe data obtained from nuclear power plant steam generator tubes (SGT). This algorithm attempts to find a balance between the two seemingly conflicting requirements of SGT eddy current data analysis, namely, detecting and identifying as many of the actual defects as possible, whilst limiting the number of false alarms to a minimum. Initial results presented in this paper look very promising. Steam generator tubes (SGT) in nuclear power plants are routinely inspected using eddy current techniques. Although a variety of probes are employed for inspecting steam generator tubes, the most commonly employed method involves the use of multifrequency differential bobbin type probes. Such probes are very simple and rugged. The structural integrity of the tube is assessed by analyzing the impedance changes of the probe as it travels within the tube. The inspection is usually carried out using four different frequencies to extract additional information concerning the state of the tube. Unfortunately the probe is sensitive to the presence of a number of other structures within the steam generator such as tube support plates, conductive deposits, tube sheets, etc. in addition to flaws present in the tube. The multifrequency measurements allow selective suppression of signal artifacts introduced by such benign structures as well as garner additional information concerning the flaws (1). The inspection of steam generators involves the testing of several hundreds of kilometers of tubing. The data generated by the inspection procedure is very large. Since manual interpretation of the data is extremely cumbersome and time consuming, the industry has considerable interest in automating the analysis procedure. Although a number of automatic analysis systems have been proposed over the years, their performance have fallen short of levels obtained using manual procedures. Typical problems associated with automatic procedures include high false alarm rates and or poor detection/characterization performance. This paper describes anautomatic procedure for analyzing multifrequency eddy current probe data derived from the inspection of nuclear steam generator tubes. The procedure uses a multi-step method to accomplish the task. The first step involves a filtering process to minimize the noise contained in the signal. The second step involves a two-stage process for identifying segments of the signal stream that represent defects. The third stage involves the classification of signals. Initial results obtained using this approach indicate that it is possible to build an automated system capable of meeting the seemingly conflicting the need for high detection and low false alarm rate.
Laryngeal keratinocytes show variable inhibition of replication by TGF-beta

The response of secondary human laryngeal epithelial cells to transforming growth factor-beta (TGF-beta) was investigated, and this response was compared with that of epithelial cells derived from virally induced laryngeal papillomas. In most cases, both normal laryngeal epithelial cells and those derived from laryngeal papillomas exhibited growth inhibition in response to 10 ng ml-1 TGF-beta. Response was not a function of cell density or proliferation rate when cells were in a low-calcium medium, but was reduced in high calcium. Using keratinocytes derived from several different tissue explants, we found that cells grown from different explants show marked variation in response to TGF-beta.
Contributions to veterinary medicine from animal research

Abstract Research involving the use of animals has contributed much to our understanding of basic physiologic mechanisms and how they become altered in disease. By employing animal models, investigators have developed new drugs for the treatment, vaccines for prevention and medical devices for the control of diseases in animals and humans. Veterinary researchers have pioneered therapy for animals and in many instances humans have benefitted as well.
Magnetohydroelectric waves in a fluid dielectric

A theoretical wave behavior in a magnetized fluid dielectric is deduced. The wave consists of oscillations of magnetic, kinetic, and electrostatic energies.
Why don't physicians consider depression in the elderly? Age-related bias, atypical symptoms, and ineffective screening approaches may be at play.

In 1990, as authorized and requested by Congress, President George H. W. Bush proclaimed the 1990s the Decade of the Brain. 1 It was an extraordinary decade: advances in the basic neurosciences and in diagnosis and treatment of neurologic and psychiatric illnesses during that period are unparalleled. Sadly, though, one of the most common, most morbid, and yet most treatable of all brain illnesses still goes undiagnosed with frightening frequency.
Elastoplastic truss design using a displacement based optimization

Abstract A displacement based optimization (DBO) method is applied to truss design problems with material nonlinearities, to explore feasibility and verify efficiency of the method as compared to traditional structural optimization. Minimum-weight truss sizing problems with various path-independent elastoplastic laws, including elastic perfectly plastic, linear strain hardening, and Ramberg–Osgood models, are investigated. This type of material nonlinearity allows us to naturally extend the linear elastic truss sizing in the DBO setting to nonlinear problems. To implement the methodology a computer program that uses the commercially available optimizer DOT by VR&D and IMSL Linear Programming solver by Visual Numerics is developed. Several test problems are successfully solved using the DBO approach and solutions are compared to those available in the literature, demonstrating significant reduction of computational time in comparison to the traditional structural optimization method. In particular, the DBO approach is found to be suitable for truss topology design since the method allows member areas to have cross-sectional areas equal to zero exactly.
Biologically based distributed control and local reflexes improve rough terrain locomotion in a hexapod robot

Distributed control and local leg reflexes enable insects to cope easily with terrain that would defeat many legged robots. An insect-like hexapod robot incorporating biologically based control effectively responded to mechanical perturbations using active and passive compliance and a local stepping reflex. An elevator reflex and a searching reflex addressed unexpected obstacles and loss of support, respectively. The robot exhibited a range of gaits using stick-insect-based distributed control mechanisms and negotiated irregular, slatted and compliant surfaces with this biologically based control strategy.
Pathogenesis and prevention of hepatitis C virus-induced hepatocellular carcinoma

Hepatitis C virus (HCV) is one of the major aetiologic agents that causes hepatocellular carcinoma (HCC) by generating an inflammatory, fibrogenic, and carcinogenic tissue microenvironment in the liver. HCV-induced HCC is a rational target for cancer preventive intervention because of the clear-cut high-risk condition, cirrhosis, associated with high cancer incidence (1% to 7% per year). Studies have elucidated direct and indirect carcinogenic effects of HCV, which have in turn led to the identification of candidate HCC chemoprevention targets. Selective molecular targeted agents may enable personalized strategies for HCC chemoprevention. In addition, multiple experimental and epidemiological studies suggest the potential value of generic drugs or dietary supplements targeting inflammation, oxidant stress, or metabolic derangements as possible HCC chemopreventive agents. While the successful use of highly effective direct-acting antiviral agents will make important inroads into reducing long-term HCC risk, there will remain an important role for HCC chemoprevention even after viral cure, given the persistence of HCC risk in persons with advanced HCV fibrosis, as shown in recent studies. The successful development of cancer preventive therapies will be more challenging compared to cancer therapeutics because of the requirement for larger and longer clinical trials and the need for a safer toxicity profile given its use as a preventive agent. Molecular biomarkers to selectively identify high-risk population could help mitigate these challenges. Genome-wide, unbiased molecular characterization, high-throughput drug/gene screening, experimental model-based functional analysis, and systems-level in silico modelling are expected to complement each other to facilitate discovery of new HCC chemoprevention targets and therapies.
2010 Report of the Executive Vice President and Chief Executive Officer: keeping our focus during a difficult time.

Let me begin my remarks today by talking about ASHP’s efforts related to health care reform, a major piece of social and political legislation that will change the face of health care in the United States over the coming decades. The Patient Protection and Affordable Care Act creates a number of
Cation ordering in Ca2La8(SiO4)6O2

Abstract The distribution of La3+ and Ca2+ over the cation sites in Ca2La8(SiO4)6O2 was determined by single-crystal X-ray diffraction. Ca2La8(SiO4)6O2 has the apatite structure, and all available evidence indicates that the space group is P6 3 m , thus precluding a completely ordered structure. The 6h lattice sites are occupied by La3+. In contrast, the 4f sites are occupied equally by La3+ and Ca2+ ions. Consideration of the properties of the La3+ and Ca2+ ions suggests that this distribution is thermodynamically favored for this composition. A simple Ising model suggests ordered columns. These would not be precluded by space group P6 3 m , if the correlation between adjacent columns were random.
NiFe2O4@SiO2 Nanoparticles Stabilized by Porous Silica Shells

NiFe2O4 nanoparticles stabilized by porous silica shells (NiFe2O4@SiO2) were prepared using a one-pot synthesis and characterized for their physical and chemical stability in severe environments, representative of those encountered in industrial catalytic reactors. The SiO2 shell is porous, allowing transport of gases to and from the metal core. The shell also stabilizes NiFe2O4 at the nanoparticle surface: NiFe2O4@SiO2 annealed at temperatures through 973 K displays evidence of surface Ni, as verified by H2 TPD analyses. At 1,173 K, hematite forms at the surface of the metallic cores of the NiFe2O4@SiO2 nanoparticles and surface Ni is no longer observed. Without the silica shell, however, even mild reduction (at 773 K) can draw Fe to the surface and eliminate surface Ni sites. Bright field TEM images of SiO2@NiFe2O4 nanoparticles packed to form nanospheres (A) or nanorods (B). The silica shell is 10–20 nm thick.
Depression is associated with increased severity of co-morbidities in bariatric surgical candidates.

Abstract Background Depression is prevalent among bariatric surgical patients, and previous studies have suggested a link between depression and quality of life. Our objective was to examine the relationship between depression and other co-morbidities of obesity at a university hospital in the United States. Methods Data were collected from 1368 consecutive patients evaluated for bariatric surgery. The demographic and co-morbidity profiles of these patients were compared between the depressed and nondepressed individuals. Depression was defined as an Assessment of Obesity-Related Co-morbidities score of ≥3, signifying that the patient required medical treatment for (score of 3) or had complications of (score of 4–5) depression. Results The prevalence of depression among these patients was 36%. The mean age of the patients with depression was older (44.3 ± 9.4 versus 42.2 ± 9.6, P P P P P P P P P Conclusion This report has characterized a link between depression and other co-morbidities in bariatric surgical patients. This association was independent of the body mass index. Although a causal relationship could not yet be identified, our findings indicate that depression, in this patient population, is associated with a greater prevalence and increased severity of medical co-morbidities that express distinct physical symptoms.
Atmospheric structure generated by entrainment into clouds

Abstract The physical principles of entrainment into clouds and the subsequent history of the cooled entrained parcels are discussed. Aircraft measurements of the layered structure of the atmosphere are presented showing the important role of the wet bulb potential temperature, θw, in determining the temperature jump at inversions. Theoretical conjectures relating to the entrainment rate at inversions all need to be tested against observations in the atmosphere, and these data show, in widely different circumstances, that inversions are formed in conditions which maintain a constant θw above and below the inversion. Thus the criteria to be met at inversions include one in which erosion takes place only when entrained parcels are denser than the air below the inversion (and then proceeds with great rapidity). In the examples measured here inversions are not eroded to any appreciable extent into stable overlying air beyond what would be expected from the cooling due to the latent heat due to evaporating drops. The converse criterion required is that when a lowering cloud base increases θw in the region below the inversion, rapid erosion occurs before significant latent instability accumulates. This interpretation is consistent with the theoretical descriptions of the processes given by Telford and Chai (1984) in regard to the various stages of inversion growth. Cumulus clouds fit into this description as the examples given here show. These data raise the question as the whether accurate measurements should be undertaken to find out if there are cases of inversions formed by other possible mechanisms. Whether the mechanism discussed here, later modified by differential advection across the shear surface, can explain other observed inversions where the constant θw condition in clear air is not met, is a matter of interest. An improvement in the measurement of θw is essential before general conclusions can be reached.
Distinguishing between a white dwarf and a neutron star in an X-ray binary

It is proposed that the single most useful clue to the nature of the accreting compact star in an X-ray binary is its ratio of X-ray to visual luminosity Lx(2–10 keV)/Lv. Present data indicate that typical Lx/Lv ratios are ∼4 for white dwarfs, and ∼5000 for neutron stars. These numbers are straightforward consequences of the energetics of accretion, and are approximately independent of the distance, stellar mass, and mass transfer rate. The data suggest that the ratios are also not very sensitive to any of the other system parameters, except the radius of the compact star.
Withdrawal seizures seen in the setting of synthetic cannabinoid abuse.

The recent rise in the abuse of synthetic cannabinoid receptor agonists (Spice, K2) has led to an increase of patients presenting to emergency departments (EDs) with complications stemming from their abuse. We present a case of withdrawal seizures seen in a chronic abuser of these herbal mixtures who stopped using them abruptly. Seizures have been reported in the literature in the setting of abuse, but not during withdrawal [1]. A 29-year-old man with a history of depression and polysubstance abuse presented to our ED with the complaint of a seizure. The patient reported getting dressed that morning and the next event he could remember was awakening inside the ambulance. Paramedics reported witnessing full body shaking consistent with a tonic-clonic seizure. The seizure activity resolved spontaneously, and this was followed by a postictal state. The patient denied any bladder or bowel incontinence or tongue biting. He did although report his tongue being sore. The patient admitted to smoking “K2” on at least a daily basis. The patient also admitted to drinking a large quantity of gin the previous night and woke up with “hangover” symptoms. The patient’ sl ast K2 use was more than than 24 hours before the seizure. The patient denied any previous seizures history other than 2 months ago when he last stopped abruptly usingsynthetic cannabinoids.Atthat time,the patient had stopped the synthetic cannabinoid abuse for approximately 24 to 36 hours and had onset of seizure-like activity, which led to injuries resulting in compression fractures of multiple thoracic vertebrae (T3 and T4). He presented to our ED then to be evaluated for back pain, but received no investigations for his seizure activity. While in the ED for this current evaluation, the patient proceeded to have 3 witnessedepisodes of generalized tonic-clonic activityin back to back fashion without return of consciousness. These episodes were preceded by profuse diaphoresis. Intravenous lorazepam was given, and no further seizure activity was witnessed. The patient was loaded with 15mg/kg of fosphenytoin. Bloodwork obtained in the ED was notable for an elevated white blood cell count of 13.4 × 10 9 /L. A urine
Exploration of structural stability: A computer implementation

In this paper, the education of structural stability is viewed from the perspective of a range of analysis techniques emphasizing the exploratory nature of not only instability phenomenon, but also engineering problems, in general. The purpose of this research was to develop a computational-based educational platform upon which to perform “experimental” tests. Three aspects of this work are discussed: the philosophy of the platform, the design concepts behind its implementation, and the programme itself. © 2001 John Wiley & Sons, Inc. Comput Appl Eng Educ 9: 122–135, 2001
Influence of the Nature of the Catalyst Precursor on the Carbon Deposition Characteristics during Ethylene Decomposition over Copper–Cobalt

In the present study the authors have monitored the conversion of ethylene to filamentous carbon during interaction with copper-cobalt bimetallics prepared from both nitrate and chloride precursors in an attempt to determine any possible changes in the catalytic activity induced by the halide. The key steps involved in the formation of this type of carbon are as follows: (a) dissociative chemisorption of the hydrocarbon molecule at a certain set of faces of the metal particle, (b) diffusion of carbon species produced during the decomposition reaction, through the catalyst particle, and (c) precipitation of solid carbon at other metal faces to create a fibrous structure. It is generally accepted that carbon diffusion through the metal particle is the rate-controlling step in the growth process. 20 refs., 4 figs., 1 tab.
Myocardial ischemia detected by thallium scintigraphy is frequently related to cardiac arrest and syncope in young patients with hypertrophic cardiomyopathy

Abstract Objectives. The purpose of this study was to determine the frequency of myocardial ischemia as a potential mechanism for cardiac arrest and syncope in young patients with hypertrophic cardiomyopathy who experienced such complication. Backgrounds. Sudden cardiac death and syncope occur frequently in patients with hypertrophic cardiomyopathy, Although ventricular arrhythmias account for most of these events in adult patiente, the mechanism responsible for cardiac arrest and syncope in young patients has not been established. Methods. Twenty-three patients with hypertrophic cardiomyopathy, aged 6 to 23 years, with previous cardiac arrest (n = 8), syncope (n = 7) or a family history of sudden cardiac death (n = 8) were evaluated to determine the prevalence of spontaneous ambulatory ventricular tachycardia (24- to 72-h electrocardiographic [ECG] monitoring), exercise-induced myocardial ischemia (thallium scintigraphy) and inducibility of ventricular tachycardia (electrophysiologic studies). Results. Three of 15 patients with a history of cardiac arrest or syncope had ventricular tachycardia on ambulatory ECG monitoring. However, all 15 patients, had indicible ischemia by thillium scintigraphy compared with only 3 (37%) of 8 patients with no such history (p Conclusions. These data suggest that in young patients with hypertrophic cardiomyopathy, sudden cardiac arrest or syncope is frequently related to ischemia rather than to a primary arrhythmogenic ventricular substrate.
A Phantom for diffusion‐weighted imaging of acute stroke

A tissue phantom for diffusion-weighted imaging was developed, basing its contrast between two compartments on different apparent diffusion coefficients, without contrast due to T2 relaxation and proton density. These contrast properties of the phantom simulate the situation found in normal gray matter and areas of acute ischemia. A possible application of the phantom was demonstrated for the investigation of the accuracy of volume measurements based on diffusion-weighted images.
Preparation and some properties of N,N′-diethylethylenediamine-N,N′-diacetic acid and N′,N′-diethylethylenediamine-N,N-diacetic acid, including ability of the former to associate with lanthanons and yttrium

Abstract N,N′-diethylethylenediamine-N,N′-diacetic acid and N′,N′-diethylethylenediamine-N,N-diacetic acid were prepared via a classical cyanomethylation process and subsequently isolated by displacement cation-exchange chromatography. N,N′-diethylethylenediamine-N,N′-diacetic acid melted with decomposition at 205–208° and N′,N′-diethylethylenediamine-N,N-diacetic acid at 175–177°. Successive pK1 and pK2 values measured at 25° and μ = 0.10 (KNOa) for N,N′-diethylethylenediamine-N,N′-diacetic acid and N′,N′-diethylethylenediamine-N,N-diacetic acid were, respectively, 6.31, 10.42 and 4.71, 11.65. Log KLnCh+ values of 7.1, 6.9, 7.0, 7.0, 6.9, 7.0, 7.1, 7.1, 7.1 and 6.8 were determined by a potentiometric method for Ch = (anion of N,N′-diethylethylenediamine-N,N′-diacetic acid)2- and Ln = Eu3+, Gd3+, Tb3+, Dy3+, Ho3+, Er3+, Tm3+, Yb3+, Lu3+ and Y3+, respectively. Because the pK2 value of N′,N′-diethylethylenediamine-N,N-diacetic acid was so high (11.65), the formation constants of its LnCh+ species could not be ascertained below pH 7. The high pK2 value of unsymmetrical N′,N′-diethylethylenediamine-N,N-diacetic acid has been rationalized by classical arguments.
2-Acetamido-p-benzoquinone: a reactive arylating metabolite of 3'-hydroxyacetanilide.

Abstract The covalent binding to protein of 3'-hydroxyacetanilide (3HAA), its primary metabolite 2',5'-dihydroxyacetanilide (2,5DHAA), and a putative secondary metabolite thereof, 2-acetamido- p -benzoquinone (APBQ), was studied in hepatic microsomal preparations from phenobarbital-pretreated mice. All compounds were found to bind irreversibly to microsomal protein, APBQ being by far the most effective member of the group. In the case of 3HAA, binding was dependent upon the presence in incubation media of the co-factor NADPH, indicating that metabolism of 3HAA was necessary for the generation of a reactive intermediate. In contrast, NADPH decreased by more than 2-fold the binding of both 2,5DHAA and APBQ. The free radical spin-trapping agent α-(4-pyridyl-1-oxide)- N - tert -butylnitrone (POBN) did not reduce the binding of 3HAA to protein. These results support the contention that metabolic activation of 3HAA is a two-step process which involves initial aromatic hydroxylation to give the substituted hydroquinone, 2,5DHAA, followed by a second oxidation reaction (which may not be enzyme-mediated) to produce the benzoquinone derivative, APBQ. This quinone is a reactive, electrophilic intermediate which may either undergo reduction back to 2,5DHAA or bind covalently to cellular macromolecules.
On Security Flow Analysis in Computer Systems (Preliminary Report)

A formal model of multilevel security systems is presented. We examine weaknesses of current security flow analysis mechanisms. A concept of expression flows is introduced, which allows us to use various techniques to certify systems that cannot be certified using current flow analysis techniques. We provide a method for generating static authorization requirements for systems in which authorization functions are only partially specified. We also attack the problem of using dynamic authorization functions for system certification.
Intercellular bridges in the embryo of the atlantic squid, loligo pealei. II: Formation of the bridge

Incomplete cytokinesis followed by the disappearance of the midbody and spindle remnant results in intercellular bridges between the cells of the blastoderm of the squid embryo. An electron microscope study of the morphology of the stages of development of the intercellular bridge is presented. Cytokinesis ceased as the furrow base reached a diameter slightly larger than the midbody. As furrowing stopped, a dense material accumulated to form a cylindrical sheath 50 nm thick, lining the inner surface of the furrow base. Proteolytic enzymes showed this material to have a significant protein component. As the midbody broke down, vesicles lined the inner surface of the bridge sheath. In this configuration, there was cyto-plasmic continuity between the cells, and organelles appeared to pass through the bridge. The intercellular bridge could become temporarily closed. Vesicles entered the channel and fused with the vesicles lining the inner surface of the sheath. The vesicles enlarged until the channel became occluded with a series of transverse cisternae, the edges of which were embedded in the material of the sheath. When the bridge reopened, the transverse cisterna appeared to dissociate from the sheath, move out of the channel, and break down. Occasionally bridges were seen in which the bridge wall appeared distorted into lobes. It is suggested that such bridges might be in the porcess of breaking down, resulting in the final separation of the cells.
Can fixed views of ability boost performance in the context of favorable stereotypes

Prior research has demonstrated that stereotypes affect negatively stereotyped groups in part through the implied immutability of group members’ abilities. Accordingly, a belief that ability is malleable through effort and hard work has been shown to boost the performance of negatively stereotyped groups. We predicted, however, that among favorably stereotyped groups, a belief that ability is fixed would reinforce the immutability of the group differences upon which stereotype-induced social comparisons are made [Walton, G. M., & Cohen, G. L. (2003). Stereotype lift. Journal of Experimental Social Psychology, 39, 456–467] and result in enhanced performance. We found experimental support for these predictions in two favorably stereotyped groups in math: Asians (Study 1) and men (Study 2). Perceived difficulty of the math test helped explain the performance effects in Study 2. Implications of schooling emphasizing innate ability for exacerbating achievement gaps are discussed.
Patient Outcomes in Magnet-Based Implantable Auditory Assist Devices.

Importance Magnet-based implantable auditory assist devices (MIAADs) are a recent development in bone-anchored hearing devices. This report increases the number of children studied with specific outcome criteria and provides detailed solutions to avoid device use difficulties in other centers considering this device. Objective To assess hearing thresholds, use rates, and complications in children implanted with a MIAAD for conductive hearing loss. Design, Setting, and Participants Retrospective analysis of children implanted with an MIAAD at an ambulatory care quaternary referral center since the Food and Drug Administration approved the Sophono device (Sophono Inc) for use in the United States (May 2011 through January 2013). Ten pediatric patients were implanted for conductive hearing loss (14 ears; mean age at implantation, 9 years [range, 3.8-17.2 years]). Diagnoses included aural atresia (n = 7) and chronic ear disease and cholesteatoma (n = 3). Interventions Implantation of MIAAD and management of skin complications. Main Outcomes and Measures Demographics, hearing thresholds, use rates, and complications were assessed. Results After fitting with the magnetic baseplate and sound processor, the mean (SD) aided pure-tone average was 20.2 (6.0) dB hearing level (HL), with a mean (SD) functional gain of 39.9 (12.4) dB HL. There were no surgical complications. Negative outcomes were assessed following fitting of the sound processor. The skin complication rate was 35.7%, including skin breakdown (n = 2) and pain and erythema (n = 5), which resulted in decreased use of the device for these patients. Intervention included decreasing the magnet strength, graduated wearing schedule, antibiotic ointment, barrier protection, and reoperation for well widening with Alloderm (LifeCell Corporation) placement. Patients without skin complications are consistent users of their device, with an average daily use of 8 to 10 hours. Conclusions and Relevance The MIAAD device has equivalent levels of hearing restoration to other previously described methods of intervention for children with conductive hearing loss. This early report indicates high rates of skin difficulties and a need for improved methods of implantation, magnetic baseplate fitting, and device use. We suggest decreased magnet strength at the initial fitting, a graduated wearing schedule, caution with patients who have a history of skin issues from a bone-anchored hearing aid or multiple surgical procedures, and parent counseling regarding potential skin irritation.
Category-theoretic aspects of abstract elementary classes

Abstract We highlight connections between accessible categories and abstract elementary classes (AECs), and provide a dictionary for translating properties and results between the two contexts. We also illustrate a few applications of purely category-theoretic methods to the study of AECs, with model-theoretically novel results. In particular, the category-theoretic approach yields two surprising consequences: a structure theorem for categorical AECs, and a partial stability spectrum for weakly tame AECs.
Alteration of arterial vasomotor function in vitro by gene transfer with a replication-deficient adenovirus

Gene transfer technologies offer great potential both to investigate and alter the course of vessel wall pathophysiology. Replication-deficient adenovirus vectors appear particu larly useful for th...
Students of Colour as Cultural Consultants: A Self-study of Race and Social Justice Issues in a teacher Education Programme

This paper documents our learning over a 3-year period from students of colour in our M.Ed. certification programme. Students of colour are always a minority (8% to 20%) in our programmes. Despite a variety of efforts, these students continued to complain that we were not meeting their needs or dealing adequately with diversity issues. The students of colour became our cultural consultants as we talked about their perceptions of our teaching and the programme. As two white middle-class professors and one Asian doctoral student, we learned different things from this self-study. Our major recommendation is that students of colour be given a separate space to talk with each other and with those who are teaching them.
Chiral separations in capillary electrophoresis using proteins as stereoselective binding agents

Proteins are receiving increased attention in capillary electrophoresis (CE) for use as ligands in chiral separations. This review examines the types of proteins that have been employed in CE for the analysis of chiral compounds and provides a summary of applications for such an approach. Several formats for this type of analysis are discussed, including methods that use immobilized proteins (i.e., affinity capillary electrochromatography and capillary gel affinity electrophoresis) or techniques that use proteins as running buffer additives (i.e., affinity capillary electrophoresis). The role of various experimental factors in these separations are considered, and a comparison is made between the general analytical properties of CE systems that use immobilized versus solution-phase proteins.
pH-Dependent Excited-State Dynamics of [Ru(bpy)(3)](2+)-Modified Amino Acids: Effects of an Amide Linkage and Remote Functional Groups.

The pH-dependent photophysical properties of a series of polypyridyl ruthenium-substituted amino acids were investigated by steady-state and time-resolved luminescence spectroscopy. [H3N−DAPA(Rub2m)−OH](PF6)3 (1), [H3N−DABA(Rub2m)−OH](PF6)3 (2), [H3N−Orn(Rub2m)−OH](PF6)3 (3), and [H3N−Lys(Rub2m)−OH](PF6)3 (4) were obtained by formation of an amide link between the ω-NH2 group of the respective commercially available amino acid and [Rub2(m-OH)]2+ (b = bipyridine, m-OH = 4‘-methyl-2,2‘-bipyridine-4-carboxylic acid). Due to the absence of significant electronic interactions between the ruthenium chromophore and the amino acid moieties, the energetics and extinction coefficients of the absorption spectra of 1−4 do not change as a function of pH. The luminescence intensities of these complexes, however, show a marked dependence on pH. At low pH (<2), quenching via excited-state protonation of the amide link leads to short lifetimes. In the pH 2−8 range, the lifetimes depend on the amino acid side chain length ...
FEL: the field encapsulation library

The paper describes the Field Encapsulation Library (FEL), which provides a grid independent application programmer's interface to gridded three dimensional field data. The C++ implementation of FEL is described, stressing the way in which the class hierarchy hides the underlying grid structure in a way that allows visualization algorithms to be written in a completely grid independent manner. Appropriately defined coordinate classes play an important role in providing this grid independence. High performance point location routines for data access are described and performance times are provided.
Regulation of phosphoenolpyruvate carboxykinase (GTP) gene transcription

Transcription of the gene for phophoenolpyruvate carboxykinase is regulated by several hormones which control the level of glucose synthesis in vertebrate animals. A 490 bp segment located at the 5’ end of the structural gene contains the necessary regulatory elements to account for the pattern of transcriptional regulation characteristic of the phosphoenolpyruvate carboxykinase gene. Multiple cis binding sites within the promotoer and nuclear binding proteins have been identified and shown to play a role in the regulation of gene transcription. The interaction of these transcription factors with each other and with the phosphoenolpyruvate carboxykinase promoter is central to the regulated expression of this gene. The key role of cAMP and insulin in controlling the level of gene transcription will be discussed and related to the function of transcription factors currently known to regulate the tissue specific expression of the phosphoenolpyruvate carboxykinase gene.
Microeconomic foundations of cyclical irregularities or ‘chaos’

Abstract Phenomena described variously as pseudorandom, irregularly-cyclical, or chaotic can appear in comparatively-simple dynamic aggregate models. This paper takes a microeconomic perspective and examines conditions in the small which appear to underlie irregular behavior in the large. The point of departure is Day's (1982a) nonlinear version of the neoclassical aggregate growth model which exhibits both conventional and irregular dynamics. The microeconomic approach, which employs one-dimensional cellular automata to simulate departures from equilibrium investment paths, yields information on the likely frequency of chaotic phenomena and on their expectational properties. In particu;ar, the automata-theoretic approach generates a rigorous and easily-applied classification scheme for dynamic systems and the data produced by them. It is shown that plausible variations in business behavior within a deterministic microeconomy support chaotic macrodynamics as well as two simpler types of behavior: uniformity over time and regular periodicity. A surprising result is the finding that the same economy can also produce a type of behavior that is qualitatively richer than chaos and far more interesting in its expectational and economic implications. The last phenomenon can manifest itself in aggregate data compiled from the micro-model as an apparent profound structural or regime change. It turns out that only seemingly minor alterations in the parameters of a model microeconomy account for which of these four qualitative macro behaviors will appear.
The collagen-like triple helix to random-chain transition: experiment and theory.

Abstract The thermal stabilities in solution of guinea pig skin collagen and three synthetic polytripeptide models for collagen, poly( l -prolyl- l -seryl-glycyl), poly( l -prolyl- l -alanyl-glycyl), and poly( l -prolyl-glycyl- l -prolyl), were monitored by observing the temperature-dependence of the circular dichroism spectra. Analysis of the melting temperatures for these polytripeptide sequences suggested a number of factors which should be included in a description of the thermodynamic stability of the collagen triple helix. Among these contributions are: (a) the primary sequence; (b) the molecular weight and polydispersity of the polymer; and (c) the extent of polymer-solvent interaction. A semi-empirical equation incorporating these factors was derived to describe the two-state triple helix to random-chain transition. The enthalpy and entropy parameters employed in the equation, with the exception of those involving polymer-solvent interactions, were calculated by theoretical conformational analysis. In order to evaluate the polymer-solvent interaction energies, it was necessary to calibrate the equation for each solvent system. The predicted versus observed melting temperatures were compared for the synthetic polymers in two solvents of different polarities, water and 1,3-propanediol.
Thin-zone TAP-reactor – theory and application

Abstract A new reactor model for TAP pulse response experiments called a ‘thin-zone reactor’ is developed and applied to irreversible adsorption/reaction and reversible adsorption. In a thin-zone reactor, concentration gradients across the catalyst bed can be neglected, and diffusion and chemical reaction can be separated. The expressions for kinetic parameters for a thin-zone reactor can be calculated using moments, and are much simpler than the expressions for a one-zone or a three-zone reactor. The thin-zone model is particularly useful for investigating fast chemical reactions, since the extent of reaction can be controlled by the thickness and position of the catalyst zone. The expression for conversion in the case of irreversible adsorption/reaction in a thin-zone reactor is governed by a relationship that is analogous to the expression for first-order reaction in a CSTR. Moment based ‘fingerprints’ are defined for irreversible adsorption, reversible adsorption, and diffusion. The thin-zone model is used to determine kinetic parameters for the oxidation of propene over a VPO catalyst.
Differences in Thyroid Function Between Triiodothyronine-Treated and Hypophysectomized Rats: Binding Glands

The fate of I131 during the first 16 min after its subcutaneous injection was observed in the binding thyroids of hypophysectomized or triiodothyronine (T3) -treated rats which had or had not been given thyrotropin (TSH). The thyroids of T3-treated rats (compared with those of hypophysectomized rats) concentrated radioiodide poorly but, especially early after the injection of I131, converted it more efficiently to organic I131. The fractional rate of binding of thyroidal radioiodide (Kb) changed with time after I131 injection. An elevation of Kb by TSH was clear-cut throughout the experimental period in T3- treated rats, but only toward its end in hypophysectomized animals. Thyroidal clearance of serum I131 by organic binding (Co/m) was more efficient in hypophysectomized rats than in T3-treated animals; when TSH was given, Co/m in the latter was raised to levels which, during the first 12 min after I131 injection, exceeded those seen in TSH-treated hypophysectomized rats. The results emphasize not only d...
Inactivation of cathepsin B1 by diazomethyl ketones

Abstract Benzyloxycarbonyl-phenylalanyl diazomethyl ketone and benzyloxy-carbonyl-phenylalanyl-phenylalanyl diazomethyl ketone, which have been shown to inactivate the thiol protease papain by a mechanism different from that of substrate chloromethyl ketone derivatives, have now been examined as inhibitors of cathepsin B1 of beef spleen. The dipeptide derivative irreversibly inactivates this protease rapidly, apparently by affinity labeling.
Imageability and distributional typicality measures of nouns and verbs in contemporary English.

Dissociations between noun and verb processing are not uncommon after brain injury; yet, precise psycholinguistic comparisons of nouns and verbs are hampered by the underrepresentation of verbs in published semantic word norms and by the absence of contemporary estimates for part-of-speech usage. We report herein imageability ratings and rating response times (RTs) for 1,197 words previously categorized as pure nouns, pure verbs, or words of balanced noun-verb usage on the basis of the Francis and Kucera (1982) norms. Nouns and verbs differed in rated imageability, and there was a stronger correspondence between imageability rating and RT for nouns than for verbs. For all word types, the image-rating-RT function implied that subjects employed an image generation process to assign ratings. We also report a new measure of noun-verbtypicality that used the Hyperspace Analog to Language (HAL; Lund & Burgess, 1996) context vectors (derived from a large sample of Usenet text) to compute the mean context distance between each word and all of thepure nouns andpure verbs. For a subset of the items, the resulting HAL noun-verb difference score was compared with part-of-speech usage in a representative sample of the Usenet corpus. It is concluded that this score can be used to estimate the extent to which a given word occurs in typical noun or verb sentence contexts in informal contemporary English discourse. The item statistics given in Appendix B will enable experimenters to select representative examples of nouns and verbs or to compare typical with atypical nouns (or verbs), while holding constant or covarying rated imageability.
What Constitutes Successful Weight Management in Adolescents

Effective weight loss strategies for overweight children and adolescents may reduce the risks for obesity-associated diseases or the premature death reported by van Dam and colleagues in this issue...
How Do Benthic Organisms Withstand Moving Water

Many aquatic plants and animals spend part of their lives anchored to the substratum as water flows by. There are a number of mechanisms by which such sessile organisms can affect the magnitude of the flow-induced forces they encounter, as well as the distribution and magnitude of the mechanical stresses in their bodies produced by those forces. Furthermore, the mechanical properties of the skeletal tissues of such organisms affect how much they deform and whether or not they will break in response to flow-induced stresses. There are different mechanisms by which organisms can withstand the water flow characterizing a particular type of habitat. Biomechanics is a useful tool for studying how the performance of organisms depends on their structure. Biomechanical studies should be accompanied by knowledge of the natural history and ecology of the organisms in question if they are to lead to insights about how organisms work.
Mediating Dilemmas: Local NGOs and Rural Development in Neoliberal Mexico

Analysis of the role of NGOs as mediators of change may yield important theoretical insights into the processes by which neoliberalizing projects become embedded in and consequently transformed by specific settings. In recent decades, NGOs have played an important role in mediating intertwined and often contradictory processes of political and economic liberalization in countries around the globe. However, changes to the political context in which NGOs work have altered the nature of the interventions these groups make. This article examines how members of a Mexican NGO community centered in the provincial city of Tulancingo, Hidalgo, rework cultural idioms of mediation to position themselves as legitimate intermediaries linking rural cooperatives, state officials, international donors, and global activist networks. Their strategies for confronting their own entrapment in processes of structural reform illuminate the constraints faced by Southern activists in negotiating possibilities for social change after the Washington Consensus. They also underline the importance of renewed attention to the role of intermediaries in enabling and enacting structural change.
On the Characteristics of Gravity Waves Generated by Atmospheric Shear Layers

Abstract The stability analysis of a hyperbolic tangent velocity profile in an isothermal atmosphere In the presence of the ground is presented. It is shown that such a system has a number of modes in addition to the one studied by Drazin and that unstable waves can he excited, for finite values of some minimum Richardson number of the flow, even in the limit of horizontal wavelengths going to infinity. Some of the unstable waves belonging to these new modes are able to propagate energy and momentum away from the shear zone and may therefore play an important role in microscale flow dynamics and in coupling of small-scale phenomena to mesoscale flow motions.
Campylobacter jejuni pancolitis mimicking idiopathic ulcerative colitis

Campylobacter jejuni is the most common cause of community-acquired acute bacterial diarrhea. Campylobacter diarrhea is usually accompanied by fever and abdominal pain. Campylobacter diarrhea is usually watery. Nausea, vomiting, headache, and myalgias may also be present. Tenesmus is a common feature. The majority of patients with Campylobacter diarrhea have some component of segmental colitis, usually beginning in the small bowel and progressing distally to the cecum and colon. C. jejuni is a rare cause of pancolitis. Community-acquired colitis may be caused by C. jejuni or other enteric pathogens, for example, Shigella, Entamoeba, Yersinia, Escherichia coli 0157:H7, Clostridium difficile colitis, ischemic colitis, or idiopathic ulcerative colitis. We present a case of C. jejuni pancolitis in an elderly woman. Differential diagnosis is included in the discussion. The patient’s C. jejuni pancolitis was successfully treated with a 7-day course of oral moxifloxacin.
The atomic structure of BiFeO3

Abstract The atomic positions in perovskitic BiFeO3 were determined using X-ray single crystal diffraction and neutron powder diffraction. The space group is R3c, the rhombohedral unit cell containing 2 formula units of BiFeO3. Antiferroelectricity is not permitted in this structure, but ferroelectricity is possible, although the electrical coercive field may be very high.