cssi/SciSciGPT-SciSciNet huggingface dataset:
Age structure or functional response? Reconciling the energetics of surplus production between single-species models and ECOSIM

Whole-ecosystem foodweb models, specifically the dynamic model ECOSIM, contain specific hypotheses for surplus production that differ from traditional single-species management models. Specifically, ECOSIM begins with an assumption that all species are tightly connected and energetic surplus does not arise through fishing, whereas single-species fishing theory implies that fishing leads to surplus by removing larger, older, less-productive fish from populations. Although ECOPATH production ratios and single-species estimated production levels are both derived from the dynamics of von Bertalanffy consumption and growth equations, the dynamics of ECOSIM differ from the implied bioenergetics of fishing as applied to age-structured populations. Specifically, while the ECOSIM “Arena” functional response and the von Bertalanffy equations both lead to the appearance of densitydependence in predator consumption per unit biomass, the difference in starting assumptions between the models leads ECOSIM to “fix production energetics” while age-structured models capture changes in within-population energetics between populations of younger versus older fish. This may cause ECOSIM to greatly overestimate the amount of biomass supportable in “pristine” systems of large, mature fish, especially when projections are based on models of currently exploited ecosystems. However, if the ECOSIM Arena is seen as a proxy for age structure rather than as a function of predator/prey behaviour, the original derivation of von Bertalanffy growth equations, applied as a modification of ECOSIM, may allow the predictions made by biomass dynamics ecosystem models to incorporate critical life-history characteristics of modelled populations. Afr. J. mar. Sci. 26: 289–301
Spatial variability constraints to modeling soil water at different scales

Abstract There is increasing interest in modeling soil water content over relatively large areas or scales. In general, the spatial variability of soil water content increases with scale, but it is not known how much or at which scales. High spatial variability constrains soil water models by reducing the accuracy of input parameters, calibration and verification data. It may also require representation of soil water in a spatially distributed manner. Soil water content data were collected at the Reynolds Creek Experimental Watershed at scales ranging from 12 m 2 to 2.3×10 8 m 2 to determine how scale affects spatial variability. We found significant spatial variability at the 12-m 2 scale, which could be described as random in large-scale models. The increase of spatial variability with scale was controlled by deterministic `sources' such as soil series and elevation-induced climatic effects. The satellite-derived, soil-adjusted vegetation index showed that spatial variability at the scale of Reynolds Creek (2.3×10 8 m 2 ) is not random, and may have abrupt transitions corresponding to soil series. These results suggest a modeling strategy that incorporates soil series characterized by random spatial variability nested within the larger, elevation-induced climatic gradient. The distinctions between soils and elevations is greatest early in the growing season and gradually diminish as the effects of differential precipitation and snowmelt timing are erased by evapotranspiration until late in the summer, when they virtually disappear. These conclusions are landscape-dependent, so that representation of spatial variability should be an explicit part of model development and application.
Theoretical description of the 2A′' and 2A′ states of the peroxyformyl radical☆

We use simple orbital ideas to describe the lowest two states (^2A'' and ^2A') of the peroxyformyl radical and report ab initio Hartree-Fock calculations in these states. We find that both states may be formed exothermically by association of O_2 and HCO in their ground states; however, the excited state may decompose readily to OH and CO2. The possible role of such processes in oxidation of aldelydes is discussed.
Scaffolding the Writing of Students with Disabilities through Procedural Facilitation: Using an Internet-Based Technology to Improve Performance:

Relatively little is known about the potential of web-based programs to support and scaffold the writing performance of students with disabilities. In this study, an experimental and control group of students planned and organized their ideas in order to write expository papers about self-selected topics. The experimental group used a web-based environment that scaffolded performance by prompting attention to the topical organization and structure of ideas while students were in the situated act of composing their papers. Control students used similar writing tools, but in traditional paper-and-pencil print formats. The results of the quasi-experimental study revealed that the students in the web-based scaffolding condition produced lengthier pieces and received significantly higher ratings on the primary traits associated with writing quality. The greatest effects were evident in terms of experimental students' abilities to produce topic sentences and to generate more topically coherent pieces overall. T...
An assessment of the potential application of the Transfer of Knowledge Through Expatriate Nationals (TOKTEN) programme in sub-Saharan Africa

Abstract The Transfer of Knowledge Through Expatriate Nationals (TOKTEN) programme provides an opportunity for third world professionals currently working in first world economies to volunteer their services and expertise towards an economic development project in the less developed world. According to its organizers, the success of the programme in Southern Europe, Asia and the Caribbean, hinges primarily on the ‘home country’ rule by which professionals are assigned only to their countries of origin. Although African countries can benefit enormously from TOKTEN, very few of them have actually enrolled in the programme. TOKTEN's implementation strategy is assessed in this paper with a view to determining a framework for ensuring its more effective application in sub-Saharan Africa.
CHROMOSOMES AND COMPATIBILITY IN THE ALOINAE

In the course of some cytological investigations data were obtained on chromosome number and form in the Aloinae which may be of interest to the systematist. Taylor (I925) has made careful comparisons of the chromosome morphology in some species of Aloe, Gasteria, and Haworthia, and has found as the haploid complement in all, four long and three short chromosomes. In Gasteria all but one of the large chromosomes have subterminal constrictions. The odd one has its constriction somewhat further removed from the end and bears a " satellite " at the distal end. Haworthia is essentially like Gasteria., but here the odd chromosome does not bear a " satellite," and two of the others give indications of a secondary constriction in the short " arm" of the chromosomes. In Aloe arborescens Mill. and A. saponaria Haw. three of the large chromosomes resemble the odd one of Haworthia; the fourth, which bears a satellite, has the fiber constriction more nearly terminal-i.e., like the three of Gasteria. Ferguson (I926) has investigated a number of species in four different genera of the Aloinae. Four long and three short chromosomes constitute the usual haploid complement in all the genera she observed, although there is a tetraploid species in each. She did not find the particular distinguishing features described by Taylor. A similar complement of five long and twentyfive short pairs of chromosomes has been described in the Central American genera Yucca and Agave (O'Mara, I93I ; McKelvey and Sax, I932). In the present investigation descriptions are based only on figures from the first pollen grain division. It is possible that chromosomes are more " contracted" here than in the somatic divisions, but the essential features of their morphology seem clear, especially since they tend to lie flat on the equatorial plate, which is usually not the case in somatic divisions. Smear preparations were used exclusively. These were fixed and stained in aceto-carmine, acetohaematoxylin, and chrom-acetic-osmic followed by crystal violet. In AWlo grandidentata the writer has observed four long and three short chromosomes. Sax found a similar condition in A. striata. The A. vera examined showed three long, one intermediate, and three short chromosomes. The following species of Gasteria were found to have the usual complement: G. brevifolia, G. carinata, G. disticha; G. elongata, G. lingua, G. mollis, G. nigricans, G. planifolia, G. pitlchra, G. subcarinata, G. sildcata, G. verrucosa.
Techniques for assessing the effects of uncertainties in thermodynamic models and data

Thermodynamic models and experimental data exhibit the usual systematic and random errors. The severity of their errors depends on their use, such as for process calculations in a process simulator. Similarly, the value of better thermodynamic models and/or data should be measured with reference to such use. We have developed techniques for quantification of such thermodynamic-induced process uncertainties via Monte Carlo simulation, regression analyses, and analogies to optimization. The influence of experimental data sources and data types on the uncertainty of thermodynamic models is studied. Details and applications of our new sampling strategy (EPS), which accounts for the high degree of correlation between thermodynamics model parameters, is given. This procedure directly uses the regression results in a way that is much more powerful and mathematically accurate than traditional covariance matrix techniques. Level sets are used for the Monte Carlo samples so that unbiased accurate sampling of the entire feasible region is obtained. Comparison with traditional Monte Carlo sampling, Latin Hypercube sampling (LHS), and Shifted Hammersley sampling (SHS) are shown. The result is an unbiased estimate of uncertainties that reduces the over- and under-estimations common in traditional techniques. The approaches presented can be used for safety-factor/risk analysis, guidelines for simulator use, experimental design, and model comparisons. They allow determinations of the value of obtaining additional phase-equilibrium data and the potential value of improved phase-equilibrium models. Examples and case studies of these applications are provided.
The combinatorics of transition matrices between the bases of the symmetric functions and the B n analogues

Abstract In this paper, we develop the combinatorial interpretations of the transition matrices between the bases of the Bn analogues of the symmetric functions. In order to provide a complete reference, we have included a summary of the transition matrices for symmetric functions as well.
Simultaneous cytokinetic measurement of aneuploid tumors and associated diploid cells following continuous labelling with chlorodeoxyuridine

Cells from a murine tumor, MCa-K, were continuously labelled with the thymidine analogue chlorodeoxyuridine (CldUrd) and analyzed by bivariate flow cytometry in order to measure the growth fraction (GF) and potential doubling time (Tpot) of both the DNA-aneuploid tumor cells and the associated DNA-diploid cells. MCa-K has a DNA index of 1.7, rendering two, partially overlapping, populations observable with labelled and unlabelled cells in each population. The data from these tumors may be divided into three regions of differing DNA content, with one region containing a pure DNA-diploid population, a second region with both cell types, and a third region including only DNA-aneuploid cells. Equations are presented to characterize the fractions of labelled cells in each region as a function of labelling time and cell type, thereby permitting estimation of the proliferative properties of the populations. These equations include the possibility that DNA-aneuploid cells cease cycling both in G1 and in S phase to account for the observed numbers of unlabelled cells with S phase contents. The estimated value of Tpot of the DNA-diploid cells is 126.0 h with a GF of 42%, while that of the DNA-aneuploid cells is 36.9 h with a GF of 69%. It is also estimated that between 2% and 6% of all DNA-aneuploid cells starting DNA synthesis cease cycling, leading to 25% of the cells having an S-phase DNA content being noncycling.
A crystal modulating protein from molluscan nacre that limits the growth of calcite in vitro

Protein-mediated biomineral formation and polymorph selection in the mollusk shell involves the participation of a number of different proteins. One of these proteins, AP7, has been identified as a participant in nacre (aragonite) formation in the mollusk Haliotis rufescens. However, the role(s) of this protein in aragonite formation is (are) poorly understood, due to the fact that low quantities of this protein are recoverable from the nacre matrix. To overcome this problem, we employed stepwise solid-phase tBOC synthesis to recreate the 66-AA single-chain protein AP7 and utilized this synthetic form for in vitro mineralization studies. We find that the AP7 protein promotes incomplete or interrupted crystal growth and step edge roundening in a concentration-dependent fashion. Using synthetic peptides which represent the 30-AA N-terminal (AP7N) and 36-AA C-terminal (AP7C) subdomains of AP7, we have identified that the mineral modification activity of AP7 is localized to the unstructured, conformationally labile N-terminal subdomain. Interestingly, the 36-AA C-terminal subdomain has no observable direct effect on in vitro calcium carbonate crystal growth; however, we cannot rule out the possibility that AP7C plays an indirect role in AP7 mineralization activity. Qualitative structural studies reveal that AP7, although possessing Zn(II) fingerlike -His-(X) 6 -His, -Cys-(X) 2 -Cys-, and -Cys-(X) 4 -Cys- motifs within its C-terminal region, does not possess the structural characteristics of known Zn(II) finger polypeptides, as evidenced by the presence of an ordered, α-helical conformation within the C-terminal subdomain of apo-AP7. Given its associative nature with AP24 and the multifunctional capabilities of the 30-AA N-terminal domain, it is likely that the AP7 protein possesses multifunctional capabilities with regard to nacre formation within the mollusk shell.
A new column-generation-based algorithm for VMAT treatment plan optimization

We study the treatment plan optimization problem for volumetric modulated arc therapy (VMAT). We propose a new column-generation-based algorithm that takes into account bounds on the gantry speed and dose rate, as well as an upper bound on the rate of change of the gantry speed, in addition to MLC constraints. The algorithm iteratively adds one aperture at each control point along the treatment arc. In each iteration, a restricted problem optimizing intensities at previously selected apertures is solved, and its solution is used to formulate a pricing problem, which selects an aperture at another control point that is compatible with previously selected apertures and leads to the largest rate of improvement in the objective function value of the restricted problem. Once a complete set of apertures is obtained, their intensities are optimized and the gantry speeds and dose rates are adjusted to minimize treatment time while satisfying all machine restrictions. Comparisons of treatment plans obtained by our algorithm to idealized IMRT plans of 177 beams on five clinical prostate cancer cases demonstrate high quality with respect to clinical dose–volume criteria. For all cases, our algorithm yields treatment plans that can be delivered in around 2 min. Implementation on a graphic processing unit enables us to finish the optimization of a VMAT plan in 25–55 s. (Some figures may appear in colour only in the online journal)
Cardiogenic shock and peripheral eosinophilia in a young woman.

History of Present Illness Three weeks before her admission to our hospital, the patient developed acute onset of high fevers, pharyngitis, and myalgias. Later that evening, her primary care physician prescribed azithromycin over the telephone, and she took 500 mg of the antibiotic. The following morning, she awoke with total body urticaria and presented to the local emergency department (ED), where hematologic tests revealed a leukocyte count of 3,000/mm3 with a total eosinophil count of 120/mm3. Chest x-ray examination results were unremarkable. She was discharged from the ED with a diagnosis of viral illness and was advised to stop taking azithromycin. The patient continued to experience intermittent fever, and 6 days after the initial onset of symptoms, she developed angioedema localized to the neck with a sensation of throat tightness. She presented to the local ED, where laryngoscopy revealed supraglottic swelling. She was admitted and treated with intravenous corticosteroids. Her leukocyte count on admission was 13,000/mm3, with a total eosinophil count of 1,040/mm3. Viral titers to cytomegalovirus (CMV), EpsteinBarr virus (EPV), and blood cultures performed 3 times were negative. Complement levels were not evaluated. An echocardiogram showed an ejection fraction (EF) of 60% (range, 55%–70%). Fourteen days after the initial onset of symptoms, the patient was discharged from the hospital on a 7-day course of prednisone. She was asymptomatic at discharge, but 3 days later she experienced sharp chest pain and shortness of breath, which increased in frequency and severity throughout the following days. Twenty days after the initial onset of symptoms, she again presented to the local ED with a temperature of 39.2°C and severe persistent chest pain. Her blood pressure was 84/50 mm Hg, and her heart rate was 120/min. Chest x-ray examination results were unremarkable. The electrocardiogram showed 2to 40-mm anterior ST-segment elevation, and echocardiogram revealed an EF of 40% without pericardial effusion. Her serum creatinine kinase level was 170 IU/L (range, 27–218 IU/L), with an MB fraction of 9.1% ( 5%) and a troponin I level of 11.33 ng/mL ( 0.1 ng/mL). Her leukocyte count was 19,100/mm3, with a total eosinophil count of 1,528/mm3. Coronary catheterization at the community hospital revealed normal coronary arteries, severe biventricular dysfunction with a cardiac index of 1.85 L/min per square meter (range, 2.5–4.0 L/min per square meter), and an EF of 25%. The patient was given dobutamine and high-dose intravenous corticosteroids, and she was transferred to our hospital for evaluation of rapidly deteriorating cardiac function.
Amino acid metabolism in chameleon liver.

Abstract 1. 1. Major amino acids interconversions in Anolis carolinensis liver were studied in vivo by injection of various common-isotope and 1 4C-labeled amino acids and α-keto acids. 2. 2. Amino acid derivatives were determined and minimum yields calculated. 3. 3. Increases in serine, glutamic acid, glutamine, glycine and alanine were frequently observed. 4. 4. The carbon chain of 14C-pyruvate was incorporated into aspartate, serine, glycine, alanine, and two 5-carbon compounds, glutamine and glutamic acid. 5. 5. Transamination was apparently not of major importance in common amino acid interconversions.
A reconfigurable parallel kinematic drilling machine and its motion planning

A new reconfigurable high-speed drilling machine which is based on a planar parallel kinematic mechanism is developed and studied. The mechanism has two degrees of freedom and is driven by two linear motors which can provide both a high-speed feed rate for drilling and fast point-to-point positioning. The location and orientation of the spindle is reconfigurable for drilling different parts in a part family. The paper first introduces the schematic mechanical structure, possible configurations and functionalities of the parallel kinematic machine (PKM). Then the paper focuses on the input motion planning for ideal drilling operation, input motion planning for fast and accurate point-to-point positioning. The results are useful for improving the dynamic performance of the machine. A cycle time comparison is made between the PKM machine and a conventional machine tool.
Chlorosis in healthy and viroid-infected plants exposed to the steam additive diethylaminoethanol

Abstract Diethylaminoethanol (DAE), a neutralizing amine used to prevent corrosion of steam condensate lines, was found to cause chlorosis in young leaves of chrysanthemum, tomato, corn and bean. Sensitivity of corn and chrysanthemum to DAE was cultivar-dependent; chrysanthemum cultivar ‘Indianapolis White’ was sensitive to low concentrations of DAE, while ‘Bonnie Jean’, ‘Velvet Ridge’ and ‘Mistletoe’ were less so, and corn ‘3XD50’ was sensitive to DAE while ‘Ohio 28’ was not. The presence of latent chrysanthemum chlorotic mottle viroid (ChCMV-L) increased the sensitivity of ‘Bonnie Jean’ and ‘Velvet Ridge’ to DAE. Infection of tomatoes with mild or severe strains of potato spindle tuber viroid (PSTV) resulted in increased sensitivity to DAE under conditions of environmental stress. Leaves of chrysanthemum exhibiting DAE-induced chlorosis contained higher, but nontoxic, levels of iron and other minerals than those from non-DAE-treated plants. The importance of the presence of DAE in steam-treated growth media and steam-generated humidity is discussed.
THE AGENCY OF IMMIGRANT ENTREPRENEURS Biographies of the Self-Employed in Ethnic and Occupational Niches of the Urban Labor Market

Through an analysis of interview data and biographies of entrepreneurship, we demonstrate in this article the diverse paths to immigrant self-employment across a range of immigrant populations. We address the utilization of ethnic and occupational niches for establishing businesses and the resources that immigrant entrepreneurs draw upon as they move into self-employment. By drawing on the concept of biographical embeddedness and by emphasizing the agency of individual actors and their motivational and experiential resources, this article moves the analysis of immigrant entrepreneurs beyond the "disadvantage hypothesis" that has characterized much of the previous work on this subject.
Behavioral responses to injections of muscimol into the subthalamic nucleus: temporal changes after nigrostriatal lesions.

Abstract Changes in cellular activity in the subthalamic nucleus are a cardinal feature of Parkinson’s disease and occur in rodents after lesions of the nigrostriatal pathway, a model of Parkinson’s disease. GABA-ergic neurons from the globus pallidus provide a major input to the subthalamic nucleus. Previous electrophysiological studies revealed temporal changes in the activity of pallidal neurons after nigrostriatal lesions in rats. However, little is known about the impact of these changes on GABAergic transmission in the subthalamic nucleus. We have examined the behavioral responses to a local administration of the GABA A agonist muscimol into the subthalamic nucleus. Muscimol (0.01 and 0.1 μg) induced orofacial dyskinesia in normal rats; this response was blunted 2 weeks but enhanced 2 months after a unilateral lesion of the nigrostriatal pathway. The early decrease in the behavioral response occurred at a time when increased expression of mRNA for glutamic acid decarboxylase, the enzyme of GABA synthesis, and burst firing have been reported in the globus pallidus, suggesting an adaptive post-synaptic response to increased GABAergic transmission in the subthalamic nucleus. In contrast, we now show that glutamic acid decarboxylase mRNA is unchanged in the globus pallidus at the later time point, when electrophysiological changes also subside in this region. The increased behavioral response at this later time point may reflect a decreased activity in GABAergic inputs to the subthalamic nucleus. The results show time-dependent changes in behavioral responses to GABA A receptor stimulation in the subthalamic nucleus which may reflect adaptive changes in postsynaptic inhibitory responses after dopaminergic lesions.
Application of Maximum Entropy Sampling Design to Traveler Information System Data-Quality Evaluations

AbstractEvaluation of travel-time data quality from traveler information systems (TISs) is a critical need for many transportation agencies. To measure data quality, observations of ground-truth travel time must be collected on links in a transportation network. Therefore, selecting which links in the network to monitor is a critical step in evaluating the quality of a TIS. This paper presents a maximum entropy sampling (MES) design that can be used to objectively select a subset of links from a road network for ground-truth data collection. This approach objectively identifies subsets of links that have the greatest variability in traffic conditions. This allows for a more rigorous evaluation of a TIS to determine the system’s ability to effectively capture changing traffic conditions. The MES method was evaluated using both a simulated and an empirical data set.
Effect of DDT on antibody response to typhoid vaccine in rabbits and man.

DDT-dosed humans and animals injected with Salmonella typhi vaccine produced O, H and Vi agglutinin titers somewhat higher than controls (no DDT). This is In contrast to an earlier report that DDT-fed animals injected with this vaccine experienced a 30% decrease in antibody titre to whole organisms. Immunoglobulin levels in human volunteers were unaffected by DDT ingestion.
994-100 Acute Neurological Complications of Cardiac Catheterization: Natural History and Risk Factors

The development of an acute neurological deficit (ND) is a rare but dreaded complication of left heart catheterization. The natural history and predisposing risk factors for their development are not well known. We sought to determine the incidence, clinical outcome and variables associated with the development of ND from diagnostic left heart catheterization (LHC), angioplasty (PTCA) or valvuloplasty (V) in 6465 consecutive patients (pts) in the modern era. All cases of ND developing within 36 hours of LHC (n = 5245), PTCA (n = 1159) and V (n = 61) were collected prospectively. The clinical features and natural history of these events were studied and, using a case control method, each case was matched by month to 10, randomly chosen pts without ND, and the variables associated with developing ND were determined. Twenty-seven pts (0.4%) suffered a neurological deficit. The most common symptoms were: visual disturbances (n = 7; 26%). hemiparesis (n = 7; 26%), and facial droop (n = 7; 26%), Seizures occurred in 3 (11%), and one pt each developed dysequilibrium, transient global amnesia and transient unresponsiveness. Sixteen pts (59%) completely resolved at long-term follow-up with the majority (13/16) resolving within 24 hours. An additional 4 pts (15%) had minimal persistent deficits (diplopia, n = 2; homonymous hemianopsia, n = 2). Four pts (15%) had major deficits at follow-up (hemiparesis, n = 3; right upper extremity weakness, n = 1) and 3 pts (11%) died as a sequela. Clinical variables associated with ND and the odds ratio and confidence intervals: Female Sex 3.2; (1.4, 7.4) * Vascular Disease 3.1; (1.2, 8.0) ** ≥ 2 Coronaries Diseased 3.0; (1.2, 7.4) ** Ejection Fraction 0.4; (0.2, 1.0) ** Left Ventricular Hypertrophy (LVH) 2.9; 11.2, 7.3) ** * p l 0.01 ** p l 0.05 As a predictor of ND, female gender was independent of body surface area. Variables not associated with the development of ND included age, diabetes, hypertension, prior infarction or stroke, procedure performed, heparin dose and number of catheter exchanges. We conclude that ND occurred in 0.4% of left heart procedures and 59% resolved completely. Females have a threefold greater risk than males, and this risk is independent of body surface area. Pts with vascular disease, extensive coronary disease, LVH aand poor ventricular function are at increased risk for a neurological complication of catheterization.
Interpersonal influence and consumer innovativeness

Innovators represent a small and somewhat elusive group of consumers who are often the earliest adopters of new products. As such, marketing researchers and practitioners alike are interested in determining the personality characteristics that influence innovators to purchase a new product early in the product life cycle. This correlational study examined the relationships of three of these characteristics (susceptibility to interpersonal influence, attention to social comparison information, and role-relaxed consumption) to individual innate innovativeness. Data were collected using self-report surveys administered to 326 students at a large public university in the south-east United States. The results supported hypothesized negative relationships between consumer innovativeness and both susceptibility to interpersonal influence and attention to social comparison information, as well as a positive relationship between consumer innovativeness and role-relaxed consumption.
Comparative live bioluminescence imaging of monkeypox virus dissemination in a wild-derived inbred mouse (Mus musculus castaneus) and outbred African dormouse (Graphiurus kelleni)

Monkeypox virus belongs to the orthopoxvirus genus, infects rodents and monkeys in Africa, produces a smallpox-like zoonotic disease in humans, and has the potential for global spread and exploitation for bioterrorism. Several small animal models for studying monkeypox virus pathogenesis have been investigated. The African dormouse is a candidate natural host but is outbred and no immunological reagents exist. Although not a natural host, the CAST/EiJ mouse is inbred and animals and reagents are commercially available. We compared the dissemination of monkeypox virus by bioluminescence imaging in CAST/EiJ mice and dormice. In CAST/EiJ mice, intense replication occurred at the intranasal site of inoculation and virus spread rapidly to lungs and abdominal organs, which had a lower virus burden. Compared to CAST/EiJ mice, dormice exhibited a greater variation of virus spread, a slower time course, less replication in the head and chest, and more replication in abdominal organs prior to death.
Integral equation study of microstructure and solvation in model attractive and repulsive supercritical mixtures

The Ornstein-Zernike equation with Percus-Yevick closure was used to investigate the local environment around solute molecules in dilute supercritical mixtures and its relationship to solubility. Two binary Lennard-Jones mixtures were studied: one, attractive; the other, repulsive. Both systems were studied at high solute dilution, at supercritical temperature, and over a broad range of reduced densities (0.33<ρ/ρ c <1.6 for the attractive system; 0.33<ρ/ρ c <2.3 for the repulsive one). The attractive system exhibited significant short-ranged solvent enrichment around the solute. The difference between the average solvent density within the first, second, and third solvation shells and the bulk solvent density was found to be more pronounced over the approximate range of reduced densities 0.5<ρ/ρ c <0.8. In contrast, the repulsive system exhibited local solvent depletion, but this effect was particularly pronounced at near-critical density. A simple thermodynamic analysis shows that in dilute attractive supercritical systems the solute's chemical potential is necessarily a weak function of bulk density at constant temperature. This was indeed found to be the case. In contrast, the solute's fugacity coefficient (whose reciprocal is a direct measure of solubility enhancement for attractive systems) was found to be a very sensitive function of density. The solute's fugacity coefficient was calculated as a function of a variable distance cutoff, beyond which the mixture was assumed to be uniform. The value of the cutoff beyond which no further change in the fugacity coefficient resulted is thus an unambiguous measure of the size of the local region around solute molecules that is important for solubility. Over the range of densities studied, this quantity ranged from 3 to 5 solvent diameters for the attractive mixture
Cathode-Driven Crossed-Field Amplifier

Experimental cathode-driven (circuit-on-emitting-sole) crossed-field amplifiers have been designed and built at S-band under a Navy program (Contract No. N00039-79-C-0295). Peak and average power levels achieved were approximately one uegawatt and 20 kilowatts, respectively. Gain was nominally 30 dB at efficiencies as high as 807. Operating voltages were typically near 30 kV. Cathode-anode (circuit) isolation was better than 20 dB. Noise measurements indicated superior noise performance. CDCFAs were operated reliably for hundreds of hours. There are good prospects that efficiency, gain, and cathode-anode isolation can be iuproved even further with this device.
Dietary compliance and life style of children with coeliac disease.

Background: Coeliac disease (CD) is common and requires a permanent strict gluten-free diet (GFD). However, data concerning how the situation is experienced by children are limited. The present study aimed to investigate the compliance with a GFD and the impact of CD and GFD on the lifestyle of patients and their families, together with proposed recommendations for improvement of quality of life. Methods: Children with biopsy confirmed CD were recruited consecutively from the outpatient gastroenterology clinic. Participants were evaluated by a special questionnaire for compliance with the GFD, patients’ knowledge about CD, and the well-being and lifestyle of children and their families. Comparisons between discrete variables were performed by a chi-square test. Results: Seventy-three children of median age 9.4 (interquartile range = 5–14.5) years were evaluated. Compliance to diet was reported by 58%. Reasons for noncompliance were: poor palatability (32%), dining outside home (17%), poor availability of products (11%), and asymptomatic disease diagnosed by screening (11%). The acceptance of the GFD was reported as good in 65%, whereas avoidance of travelling and restaurants was stated by 17% and 46% of families, respectively. Most families experienced difficulties detecting gluten from the food label. Proposed factors for improvement of quality of life were: better labelling of gluten-containing ingredients (76%) and more gluten-free (GF) foods in supermarkets (58%) and restaurants (42%). Conclusions: Children with CD have low compliance with the GFD. Better education about the disease, the availability of GF products, and appropriate food labelling could improve compliance and quality of life.
Physiological Studies on the Identity of the Gonadotropic and Progonadotropic Substance(s) in Sera of Ewes Immunized Against hCG

The sera of two ewes immunized against hCG were studied intensively over a period of 3 yr for anti-, pro- and gonadotropic activities in an attempt to determine the factors responsible for these activities. Data from an additional ewe (9–437) were used for limited studies. Gonadotropic and progonadotropic responses were studied in intact immature female rats and in hypophysectomized male and female rats. In a few instances the LH contents of the sera were determined by radioimmunoassay. Gonadotropic responses were obtained in intact immature females and in hypophysectomized males but not in hypophysectomized females. On the other hand, administration of immunized ewe serum concurrently with crude or purified FSH resulted in an enhancement of the FSH response (progonadotropic activity) in both intact and hypophysectomized females. The concurrent injection of the serum with ovine LH into hypophysectomized males augmented the ventral prostate response to ovine LH. Thus, it was shown for the first time that a...
The significance of pore microarchitecture in a multi-layered elastomeric scaffold for contractile cardiac muscle constructs

Multi-layered poly(glycerol-sebacate) (PGS) scaffolds with controlled pore microarchitectures were fabricated, combined with heart cells, and cultured with perfusion to engineer contractile cardiac muscle constructs. First, one-layered (1L) scaffolds with accordion-like honeycomb shaped pores and elastomeric mechanical properties were fabricated by laser microablation of PGS membranes. Second, two-layered (2L) scaffolds with fully interconnected three dimensional pore networks were fabricated by oxygen plasma treatment of 1L scaffolds followed by stacking with off-set laminae to produce a tightly bonded composite. Third, heart cells were cultured on scaffolds with or without interstitial perfusion for 7 days. The laser-microablated PGS scaffolds exhibited ultimate tensile strength and strain-to-failure higher than normal adult rat left ventricular myocardium, and effective stiffnesses ranging from 220 to 290 kPa. The 7-day constructs contracted in response to electrical field stimulation. Excitation thresholds were unaffected by scaffold scale up from 1L to 2L. The 2L constructs exhibited reduced apoptosis, increased expression of connexin-43 (Cx-43) and matrix metalloprotease-2 (MMP-2) genes, and increased Cx-43 and cardiac troponin-I proteins when cultured with perfusion as compared to static controls. Together, these findings suggest that multi-layered, microfabricated PGS scaffolds may be applicable to myocardial repair applications requiring mechanical support, cell delivery and active implant contractility.
Effect of particle size of nanospheres and microspheres on the cellular-association and cytotoxicity of paclitaxel in 4T1 cells.

Purpose. To compare the effect of size of delivery systems on the cell-association and in vitro cytotoxicity of paclitaxel.
Methods in arthropod retinography for evaluation of spectral polarization sensitivity

We describe apparatus and methods to measure the sensitivity of arthropod eyes to wavelength and polarization. While these general methods are well-known in the retinography community, they are less familiar to the general optics community. Measurement of polarization sensitivity is particularly uncommon even among retinographers, and our research plan and example results are detailed.
ON THE EXISTENCE OF SPATIALLY PATTERNED DORMANT MALIGNANCIES IN A MODEL FOR THE GROWTH OF NON-NECROTIC VASCULAR TUMORS

Despite their great importance in determining the dynamic evolution of solutions to mathematical models of tumor growth, equilibrium configurations within such models have remained largely unexplored. This was due, in part, to the complexity of the relevant free boundary problems, which is enhanced when the process deviates from radial symmetry. In this paper, we present the results of our investigation on the existence of non-spherical dormant states for a model of non-necrotic vascularized tumors. For the sake of clarity we perform the analysis on two-dimensional geometries, though our techniques are evidently applicable to the full three-dimensional problem. We rigorously show that there is, indeed, an abundance of steady states that are not radially symmetric. More precisely, we prove that at any radially symmetric stationary state with free boundary r=R0 (which we first show to exist), there begin infinitely many branches of equilibria that bifurcate from and break the symmetry of that radial state. The free boundaries along the bifurcation branches are of the form , where l=2,3,… and |e|<e0; each choice of l and e determines a non-radial steady configuration.
Xanthochromia is not pathognomonic for subarachnoid hemorrhage.

Objective: To test the hypothesis that xanthochromia may be observed in traumatic lumbar puncture (LP). Xanthochromia, the yellow discoloration of cerebrospinal fluid (CSF) caused by hemoglobin catabolism, is classically thought to arise within several hours after subarachnoid hemorrhage (SAH). The presence of xanthochromic supernatant is often used to distinguish the elevated red blood cell (RBC) count observed in the CSF of SAH from the elevated RBC count observed after traumatic LP. Methods: The authors developed a model of traumatic LP by adding whole blood to pigment-free CSF to obtain RBC concentrations of 0, 5,000, 10,000, 20,000, 30,000, and 40,000 RBC/μL. Supernatant from centrifuged samples was assessed for xanthochromia by spectrophotometry. Xanthochromia was considered present if the absorption followed a characteristic oxyhemoglobin curve with a maximal absorption greater than 0.023 at 415 nm. Results: Samples with at least 30,000 RBC/μL demonstrated xanthochromia immediately. Samples with 20,000 RBC/μL demonstrated xanthochromia within one hour, and samples with 10,000 RBC/μL or less, within two hours. Conclusions: Cerebrospinal fluid xanthochromia may be observed within two hours after traumatic LP and sooner in samples with greater than 10,000 RBC/μL. Conversely, xanthochromia in traumatic LP with less than 5,000 RBC warrants further investigation for SAH. When the CSF RBC count is elevated above 10,000 RBC/μL, or the time between sample acquisition and analysis is prolonged, the clinician should not rely on xanthochromia to confirm SAH.
Hyperthyroidism and atrial myxoma--an intriguing cardio-endocrine association.

A 65-year-old woman presented with dyspnea and bilateral leg edema for 1 week, worsening fatigue for 1 month, and a 7-lb weight loss over the last summer. She was clinically and biochemically hyperthyroid. Echocardiography revealed a left atrial myxoma measuring 6.2 × 3.3 cm protruding into the mitral orifice and left ventricle during diastole. She was treated for Graves' disease with Iodine-131. Six weeks later, her left atrial myxoma measuring 10.1 × 6.2 × 2.4 cm was resected. She became euthyroid before surgery and then biochemically hypothyroid 6 weeks after radioiodine treatment, for which she subsequently required thyroxine replacement. Atrial myxomas are the most common primary cardiac neoplasms. At least 5% to 10% can be attributed to Carney's complex. More than two-thirds of patients with Carney's complex develop one or more cardiac myxomas. Although atrial myxomas in Carney's complex are histologically indistinguishable from the sporadic form, their clinical presentation and course is distinct. This is the first case of newly diagnosed Graves' disease that has been reported in association with an atrial myxoma. The features discussed in this article help differentiate between syndromic and sporadic atrial myxomas.
A method for judging measures of stochastic dependence: further comments on the current controversy.

A large number of reports have been published on stochastic independence between implicit and explicit measures of memory. This is often taken to imply that different memory systems mediate implicit and explicit memory performance. In these cases, stochastic independence is inferred from contingency analysis of overall success rates in two memory tasks when performance in one or both of the tasks is, to a large extent, mediated by factors other than memory. Typically, the difference between performance with studied and nonstudied items is not large in implicit memory tasks. It is argued that this must be taken into account when evaluating the contingency analysis. A method is presented for estimating the relevant joint and conditional probabilities, assuming that the aspects of performance in the two tasks that are related to memory are dependent to the maximum possible extent. The method is applied to a number of published studies, and it is shown that the difference between these estimated probabilities and those given by stochastic independence is too small to allow any conclusion to be drawn about memory systems from contingency analysis of data reported in these studies. Language: en
Serum Fatty Acids and the Risk of Fatal Cancer

To examine the relation between serum fatty acids and cancer, the authors conducted a nested case-control study of 108 middle-aged men who died of cancer and 215 men without cancer, who were enrolled in the Multiple Risk Factor Intervention Trial (MRFIT) between 1973 and 1976. Control subjects were matched to case subjects on age, smoking status, treatment assignment, date of randomization, and clinical center. After confirming the stability of the stored serum samples, the authors measured serum fatty acid levels by gas-liquid chromatography and analyzed their association with cancer. In stepwise logistic regression analyses that controlled for the MRFIT selection criteria variables and for alcohol consumption, no fatty acid was significantly associated with overall risk of cancer death (all p > 0.05). Serum levels of phospholipid dihomogammalinolenic acid (20:3), an essential fatty acid, were inversely associated with the risk of dying from lung cancer; a standard deviation increase was associated with a 32% decrease in risk (p = 0.05). Dietary cholesterol intake was associated with the risk of non lung, non-digestive tract cancers; a standard deviation increase (331 mg/day) was associated with a 75% increase in risk (p = 0.02). The authors found no evidence to suggest that increased dietary intake or serum levels of polyunsaturated fatty acids were associated with an increased risk of fatal cancer among middle-aged men at high risk for coronary heart disease. The clinical significance of the inverse association between dihomogammalinolenic acid and lung cancer death is uncertain and requires confirmation. Am J Epidemiol 1998;148:854-8.
Lattice transformations related to unique mechanical effects

Athermal and stress-induced martensitic transformations are examined in various alloys of the large family which exhibit the unique “memory” and/or “superelastic” shape memory effects (SME). Such mechanical effects are found to be intimately related to details of the martensitic and premartensitic reaction paths in each system. A common feature of various “uncommon” systems is that the usual phenomenological crystallographic analysis cannot completely describe the martensitic transformation in these systems. Addiional features represented by lattice “shuffles” or low-wavelength lattice waves, and the mechanistic role of transformation dislocations are examined. A common thread in various systems such as TiNi, CuZn, AuCd, In-Tl, and so forth, is viewed in terms of evidence related to alloying (electronic entropy) effects on lattice instability of the parent phase. Instability reflected by premonitory phenomena can be given considerable generality when related to observations in systems which exhibit similar dynamic lattice transitions, such as the second-order “athermal omega” lattice transition in Group IV-base systems. The importance of reversibility in martensitic transformation of SME alloys is emphasized. Comparisons with more common non-SME martensitic alloys are made.
Determinants of Emerging e-Commerce Markets: A Developmental Perspective

From its inception, business-to-consumer (B2C) e-commerce has represented a vehicle for distributing goods and services where numerous forces determined the development of a new market structure. The forces include sets of supplier-related, product-related, and consumer-related factors that have shaped the market development of B2C e-commerce. In this examination of the early days of B2C e-commerce market development, it was found that low value of demonstration, high frequency of returns, high frequency of gift purchase, low purchase frequency, high sensory barrier, low immediate gratification, high value of large selection, and low shopping enjoyment product characteristics were successful in predicting online product category growth. In select data, car rentals, airline tickets, hotel reservations, books, videos, and music captured significant online market share in these early online markets. Many of these categories possess the characteristics that predicted the development of the early B2C markets. ...