cssi/SciSciGPT-SciSciNet huggingface dataset:
Age-related differences in subset composition and activation responses of intestinal intraepithelial and mesenteric lymph node lymphocytes from neonatal swine.

Abstract Interesting differences were found in the phenotypes and functional responses of intestinal intraepithelial lymphocytes (IEL) and mesenteric lymph node lymphocytes (MLN) from neonatal swine aged 15 to 47 days. IEL and MLN differed significantly in their proliferative responses to the mitogens concanavalin A (Con A) and phorbol ester with ionophore (TPA/ionomycin) and to the cytokine, interleukin 2 (IL-2). IEL did not proliferate well in response to Con A, yet they were able to initiate a high proliferative response to exogenous IL-2, suggesting previous activation. In addition, the IEL response to TPA/ionomycin was very low unless the concentration of ionomycin was increased. With increasing age of the animals, response of the IEL increased. This IEL developmental response pattern was associated with a significant age-related change in T cell phenotype from CD2 - 4 - 8 cells to CD2 + 4 - 8 - cells. In contrast to IEL, proliferation of MLN to Con A and TPA at a lower ionomycin concentration was significant and not influenced by age. Unlike the IEL, MLN were unresponsive to exogenous IL-2. Similar to IEL, they produced very little IL-2 in response to Con A stimulation. Both lymphoid tissues contained 70% T cells and in the MLN more cells were CD4 + or CD4 + 8 + and fewer were CD4 - 8 - compared to the IEL. These differences between IEL and MLN in neonatal swine may reflect differences not only in the state of cell activation related to the in vivo microenvironment, but also the nature of responsive cell types in each lymphoid tissue.
The growth of population in the Chesapeake colonies: A comment

The author critically examines the findings of TL Anderson and RP Thomas concerning population estimates for the Chesapeake colonies from 1635 to 1700 and their findings on the effects of immigration and reproduction on the growth process. In the present article the methodological and empirical work of Anderson and Thomas is assessed with a focus on the accuracy of population and mortality estimates and the use of headright lists as a source of immigration information. The assumption that the population growth rate was constant during the seventeenth century is also questioned.
HER2 codon 655 polymorphism and risk of breast cancer in African Americans and whites.

Background. Several recent epidemiologic studies examined the association between breast cancer risk and an inherited, single-nucleotide polymorphism in the HER2 gene, codon 655 G to A, which leads to an amino acid substitution of Ile to Val. Results of previous studies have been mixed, with most studies showing no association but some suggesting an association in younger women or women with a family history of breast cancer. Methods. We conducted an association study of HER2 codon 655 genotype and breast cancer within the Carolina Breast Cancer study, a population-based, case-control study of in situ and invasive breast cancer in African American and white women in North Carolina. A total of 2015 cases and 1808 controls were genotyped. Results. We observed no overall association between HER2 genotype and breast cancer. However, a modest positive association (OR = 2.3, 95% CI 1.0–5.3) was observed for Val/Val + Ile/Val versus Ile/Ile genotypes in women age 45 or younger with a family history of breast cancer. Val/Val homozygotes were more common among cases with in situ versus invasive disease (P = 0.002). Breast tumors from women with Val/Val genotype were more likely to exhibit HER2 overexpression, but the results were not statistically significant (P = 0.17). Conclusions. The HER2 codon 655 polymorphism may be one of many low-penetrant genes that make a minor contribution to breast cancer, particularly in subgroups of women. Additional large studies, as well as data pooling, will be needed to estimate the contribution of such genes to breast cancer risk.
Binding of Antimicrobial Lipopeptides To Lipid Bilayers Characterized By Microsecond Molecular Dynamics Simulations

The emergence of antibiotic resistant pathogens is one of the major medical problems of the 21st century, prompting renewed interest in the development of novel antimicrobial compounds. Here we use microsecond-scale all-atom molecular dynamics simulations to characterize the structure, dynamics, and membrane-binding mechanism of a synthetic antimicrobial lipopeptide, C16-KGGK. The results of the simulations are validated by comparison with solid state NMR experiments, and yield new insights into the molecules' mechanism of action.View Large Image | View Hi-Res Image | Download PowerPoint Slide
Instrumental variables when evaluating screening trials: estimating the benefit of detecting cancer by screening.

When evaluating the benefit of detecting cancer by screening we try to answer the question, 'what would a screen detected subject's outcome have been if his/her cancer had progressed to clinical detection'. By 'outcome' we mean survival time, cancer size and stage, lead time effects and more. Because only an unethical study can answer it directly, researchers have attempted to answer the question indirectly using data from randomized cancer screening studies (subjects randomized to study (screened) or control (not screened)). Inferences are made by first selecting the cancer cohort (those subjects who are found to have cancer), then comparing subjects having screen detected cancers to subjects having clinically detected cancers. However, there are two difficulties with this approach: (i) because screening (intends to) detect cancers early, at the trial's end the study group contains more cancer cases than the control group and so the cancer cohort has some unidentified control subjects missing (that is, subjects having cancer during the screening period that have not yet been clinically detected); (ii) because screen detected cancers (may) differ from clinically detected cancers, the comparison group should include only a (non-identified) subset of the cancer cohort's control subjects (that is, only those control subjects having cancers that would have been screen detected). Statistical literature acknowledges these difficulties and attempts to solve them separately, but without success; those methods do not yield meaningful causal inferences and admit substantial bias. Recently, Angrist, Imbens and Rubin and Imbens and Rubin provide a framework for instrumental variable methods that we interpret as allowing us to make causal inferences with incompletely identified comparison groups. We apply their framework to evaluating cancer screening trials and find that we may simultaneously accommodate both difficulties while giving a meaningful answer to the question posed above. Using data from a breast cancer screening trial we demonstrate the general method with a variety of outcome measures and extensions.
Central place theory and sport tourism impacts

Abstract Although sport tourism initiatives can boost a destination’s export base, not all communities have an equal likelihood of successfully hosting such an event. The purpose of this study is to use central place theory as a basis for understanding location features that influence the economic outcomes associated with hosting a sport event. The economic impacts generated by a tournament co-hosted by two adjacent counties in different states are analyzed. The smaller county experienced a reverse false excursionist effect, as the majority of the activities took place there, yet the larger location realized nearly double the economic impacts from the event. Local economic regions and cooperative branding are discussed in light of the findings.
5-Methoxypsoralen photoadduct formation: conversion of monoadducts to crosslinks.

5-Methoxypsoralen is often substituted for 8-methoxypsoralen in the photochemotherapy of psoriasis even though the nature of the resulting photadducts in cellular DNA has not been determined. A recent molecular mechanics study with a model oligonucleotide predicted that intercalated 5-methoxypsoralen molecules would tend to favor the preferential formation of 3,4-monoadducts. Such a result would be contrary to the photoadduct patterns observed with other psoralens. In this study we show that 5-methoxypsoralen photoadducts formation is, in fact, very similar to that for other psoralens, i.e., the primary photoadduct is the 4',5'-monoadduct which can be quantitatively converted to crosslink.
Antidepressant Effect on Connectivity of the Mood-Regulating Circuit: An fMRI Study

The mechanisms by which antidepressant-induced neurochemical changes lead to physiological changes in brain circuitry and ultimately an antidepressant response remain unclear. This study investigated the effects of sertraline, a selective serotonin reuptake inhibitor antidepressant, on corticolimbic connectivity, using functional magnetic resonance imaging (fMRI). In all, 12 unmedicated unipolar depressed patients and 11 closely matched healthy control subjects completed two fMRI scanning sessions at baseline and after 6 weeks. Depressed patients received treatment with sertraline between the two sessions. During each fMRI session, subjects first completed a conventional block-design experiment. Next, connectivity between cortical and limbic regions was measured using correlations of low-frequency blood oxygen level-dependent (BOLD) fluctuations (LFBF) during continuous exposure to neutral, positive, and negative pictures. At baseline, depressed patients had decreased corticolimbic LFBF correlations compared to healthy subjects during the resting state and on exposure to emotionally valenced pictures. At rest and on exposure to neutral and positive pictures, LFBF correlation between the anterior cingulate cortex and limbic regions was significantly increased in patients after treatment. However, on exposure to negative pictures, corticolimbic LFBF correlations remained decreased in depressed patients. The results of this study are consistent with the hypothesis that antidepressant treatment may increase corticolimbic connectivity, thereby possibly increasing the regulatory influence of cortical mood-regulating regions over limbic regions.
The Triumph of Materialism: The Popular Fiction of 18th‐Century Japan

L'A. s'interesse a la litterature populaire japonaise et plus particulierement au «gesaku» apparu a la fin du 18 e siecle. Il s'efforce d'evaluer le nombre de publications et le tirage de chacune d'elles afin de mesurer l'impact de ce genre litteraire. Il montre que celui-ci comprenait un certain nombre de publications a caractere humoristique satirique. Il affirme qu'il constitue un element fondamental du discours ideologique conernant le culture, le pouvoir, la societe japonaise de la fin de l'epoque pre-moderne et qu'il reflete les conflits entre les differentes autorites feodales. Il examine la sitation du Japon entre 1600 et 1868 et examine le role ideologique joue par le gesaku
Recurrent episodes of painful and pruritic red skin lesions.

A healthy, afebrile, 24-year-old Hispanic woman presented with recurrent, painful, itchy, red skin lesions of 2 month’s duration. She had recently arrived from Nicaragua and was living with relatives in Houston, TX, USA. Erythematous plaques initially appeared on her right hip and elbow. Dermatitis was considered. Her skin lesions improved after being treated with topical triamcinolone acetonide 0.1% cream and oral hydroxyzine (50mg) once to three times daily. Shortly thereafter, tender erythematous areas of swelling developed on her right elbow and distal arm. Cellulitis was suspected. The sites resolved after she received oral amoxicillin (250mg every 8 hours for 7 days). Her third episode of lesions was evaluated at a dermatology clinic. She was afebrile. Initially, there was erythema and massive edema of the left upper eyelid (figure 1a). This began to improve within the next 48 hours (figure 1b). However, new, painful, pruritic, erythematous, firm nodules appeared on her right ear, forehead, preauricular and inferior cheek (figure 1c), and dorsal hand. A lesional skin biopsy from her right preauricular cheek and laboratory studies were performed.
Long-term factors influencing the adhesion of metallized zinc to concrete

Metallized zinc cathodic protection often is used to mitigate steel reinforcement corrosion in concrete. The zinc is flame or arc sprayed to the surface of the concrete structure to be protected. The metallized coating should be applied such that its adhesion to concrete is maximized. Factors believed to affect adhesion were investigated for pure zinc and a 85Zn-15Al alloy. On reinforced concrete samples polarized for more than 800 days at three different current densities, adhesion decreased. The reduction increased as a function of time and of the current density applied. When no current was applied, there was a small initial increase of adhesion with time. For the metallized samples that were freeze-thaw cycled, no loss of adhesion was found after 70 cycles.
Concentrations of Boron, Molybdenum, and Selenium in Chinook Salmon

Abstract The concentrations of boron, molybdenum, and selenium in young chinook salmon Oncorhynchus tshawytscha were determined in three partial life cycle chronic toxicity studies. In each study, fish were exposed to a mixture of boron, molybdenum, selenate, and selenite in the proportions found in subsurface agricultural drainage water in the basin of the San Joaquin Valley, California. Tests were conducted in well water and in site-specific fresh and brackish waters. No boron or molybdenum was detected in fish exposed to concentrations as high as 6,046 μg boron/L and 193 μg molybdenum/L for 90 d in well water or fresh water; however, whole-body concentrations of selenium increased with increasing exposure concentrations in well water and fresh water, but not in brackish water. Concentrations of selenium in chinook salmon were strongly correlated with reduced survival and growth of fish in well water and with reduced survival in a 15-d seawater challenge test of fish from fresh water. Concentrations of ...
Elevated temperature creep behavior of RSP/PM Al-13%Zr

The promise of Rapid Solidification Processing (RSP) has opened new avenues for alloy development. Major goals have been to develop aluminum alloys for elevated temperature applications because of their superior strength to weight ratio. A number of investigations have been carried out on the precipitation behavior in Al-Zr alloys, using transmission electron microscopy. An important strengthening precipitate in the Al-Zr alloy is Al{sub 3}Zr which essentially belongs to tetragonal crystal system with a c/a ratio of 4.06, a lattice mismatch in the range 1.0 to 2.88% and interfacial energy in the range 10 to 2.13 J/m{sup 2}. The purpose of this paper is to evaluate the creep deformation and fracture behavior of an Al-Zr alloy containing about 13 wt% Zr at an elevated temperature of 698 K.
A Pacific Decadal Oscillation record since 1470 AD reconstructed from proxy data of summer rainfall over eastern China

[1] Recent studies indicated that the spatial pattern and temporal variability of summer rainfall over eastern China are well correlated with the Pacific Decadal Oscillation (PDO). Here we used a data set of the drought/flood index (a proxy of summer rainfall) since 1470 AD to reconstruct the annual PDO index. The reconstruction indicates that the PDO is a robust feature of North Pacific climate variability throughout the study period, however, the major modes of oscillation providing the basic PDO regime timescale have not been persistent over the last 530 years. The quasi-centennial (75-115-yr) and pentadecadal (50-70-yr) oscillations dominated the periods before and after 1850, respectively. Our analysis suggest that solar forcing fluctuation on quasi-centennial time scale (Gleissberg cycle) could be the pace-maker of the PDO before 1850, and the PDO behavior after 1850 could be due, in part, to the global warming.
Extended Nonfiction Readers for EAP Programs.

Content-based instruction course designers have many important decisions to make when developing courses for postsecondary English for academic purposes (EAP) students. One important consideration revolves around deciding if students would benefit most from the use of sustained content (Murphy & Stoller, 2001) or a topical approach (Brinton, Snow, & Wesche, 2003). The authors advocate the sustained content approach and promote the use of extended nonfiction readers, specifically those designed for students in Grades 7–12, as primary texts for achieving course goals for intermediate-level EAP students. The authors support this stance by (a) establishing a strong case for the adoption of extended nonfiction readers in sustained content instruction, (b) introducing helpful text selection criteria, (c) describing scaffolding techniques and synthesis tasks to be used with such readers, and (d) offering tips that can assist teachers and administrators in making a programmatic transition to this pedagogical approach. For practitioners at other grade levels or in programs that endorse other content-based approaches, many of the ideas presented here are relevant with modest adaptations.
Efficacy of WAIS-R Short Forms with Special Education Referrals

The protocols of 327 students referred for psychological evaluation for possible special education services were examined using brief forms of the WISC-R. Several combinations of subtests were used to predict the FSIQ. Although significant correlations were obtained between the estimated FSIQ and actual IQ, significant t tests were also obtained, indicating significant discrepancies between the two lQs, Thirty-four protocols were selected at random and Hobby's (1981) split-half technique was applied. Again significant correlations and correlated t tests were obtained with only a very few cases having a significant shift in IQ. The authors concluded that brief forms of the WISC-R should be avoided; however, if a brief form is necessary, Hobby's technique is recommended.
Bradypus torquatus (Pilosa: Bradypodidae)

Abstract Bradypus torquatus Illiger, 1811 is a three-toed sloth commonly called the maned three-toed sloth. It is endemic to the Atlantic coastal forests of southeastern Brazil. Occasionally placed in its own genus (Scaeopus), the black mane of this three-toed sloth is distinctive. Like other sloths, B. torquatus is a high-canopy folivore with a commensal relationship with algae and invertebrates that live in its abundant pelage. B. torquatus is an endangered species that does not adapt to captive zoo settings.
Thermal degradation of phosphorus esters derived from isosorbide and 10-undecenoic acid

Phosphorus compounds derived from renewable biomaterials are of increasing interest as polymer additives. These compounds may have both a plasticizing and flame-retarding effect on a polymer matrix into which they are incorporated. The thermal degradation of a series of phosphorus esters derived from a diol generated by the esterification of isosorbide (from starch) with 10-undecenoic acid (from castor oil) followed by thiol-ene reaction with 2-hydroxyethanethiol has been examined using thermogravimetry and infrared spectroscopy. All the esters undergo degradation over the temperature range of 250–310 °C to generate a substantial residual char. Infrared analysis of samples undergoing degradation suggests that a prominent reaction is elimination of a phosphorus acid.
SOPHE at Sixty:The Best Is Yet to Come 2009 SOPHE Presidential Address

Sixty years ago, on October 22, 1949, a small group of dedicated health educators made a commitment to innovation by founding what was then known as the Society of Public Health Educators. Since that time, our organization has consistently met the definition of innovation with the introduction of new ideas, methods, and devices. This presentation celebrates highlights of SOPHE’s past 60 years and explores the challenges facing our organization. It also presents the definition of the Element—the intersection of talent and passion, the point at which people are most inspired and achieve at the highest levels—as a framework for developing our talents for the future.
The Mauna Loa environmental matrix: foliar and soil nutrients

The accumulation of total carbon, nitrogen, and phosphorus in soils, available soil nutrients, and foliar nutrients in the native dominant Metrosideros polymorpha were determined across a wide elevational range on 9 lava flows on Mauna Loa, Hawai'i. The flows included a young ( 2800 y) aa (rough surface texture) and pāhoehoe (smooth) flow on the wet east and dry northwest side of the mountain. Soil element pools and nutrient availability increased with flow age independent of climate. The dry sites accumulated organic matter and nutrients more slowly than comparable wet sites, but relative nutrient availability to plants (as indicated by soil assays and foliar nutrients) was greater in the dry sites. Accumulation of soil organic matter and nutrients occurred most rapidly in lowerelevation sites on the young flows, but the largest accumulations occurred at higher elevations on old flows. The range of sites sampled represents a complete and largely independent matrix of major factors governing ecosystem structure and function.
Spin correlations at finite temperature in an S=1 one-dimensional antiferromagnet.

We have measured the temperature dependence of equal-time spin correlations in the quasi-one-dimensional S=1 antiferromagnet, Ni(${\mathrm{C}}_{2}$${\mathrm{H}}_{8}$${\mathrm{N}}_{2}$${)}_{2}$${\mathrm{NO}}_{2}$${\mathrm{ClO}}_{4}$ (NENP), by magnetic neutron scattering. The temperature dependence of the correlation length can be described as exponentially activated with an activation energy similar to the Haldane gaps in NENP.
Preabsorptive vs. Postabsorptive Control of Ethanol Intake in C57BL/6J and DBA/2J Mice

Experimentally naive male mice of both strains were exposed to a two-bottle choice situation (ethanol vs. water) and their drinking behavior was observed during the first hour. DBA/2J mice developed a significant avoidance of 2% or 10% ethanol during the first 10 min. At 15 and 60 min following introduction of the bottles, no DBA mouse exhibited more than a 6 mg % blood ethanol level while all of the C57BL mice exceeded this concentration. Significant postabsorptive effects in the DBA mice seem unlikely at these very low blood ethanol values. Animals of both strains were examined for their ability to form lithium-induced conditioned taste aversions to 2% ethanol or 15% sucrose solutions. DBA mice readily formed conditioned aversions to both solutions, but the C57BL strain significantly avoided only the sucrose. C57BL mice appear to have difficulty in discriminating the 2% ethanol from distilled water. The neural sensitivity to ethanol was examined in both strains using the sleep time test and the grid test. C57BL mice were significantly more sensitive than DBA mice in both tests.
Is All Bone the Same? Distinctive Distributions and Properties of Non-Collagenous Matrix Proteins in Lamellar Vs. Woven Bone Imply the Existence of Different Underlying Osteogenic Mechanisms

The purpose of this review is to summarize recent functional and structural findings regarding non-collagenous matrix proteins in bone and teeth, to compare gene locations for bone and tooth matrix proteins with loci for hereditary skeletal diseases, and to present several provocative hypotheses which integrate this new information into a physiological context. Hypothesis I proposes that the molecular composition of rapidly deposited and mineralized woven bone, as well as the responsiveness of cells synthesizing woven bone to stimuli, is different from that for more slowly synthesized lamellar bone, implying the existence of distinctive osteogenic mechanisms. This review of recent research strongly supports this proposal. Briefly, the protein composition of woven bone matrix is enriched in acidic phosphoproteins BAG-75 and BSP, which are not expressed in lamellar bone, which is itself enriched in osteocalcin. De novo deposition and mineralization of woven bone occurs faster than in lamellar bone by means of a matrix-vesicle-assisted mechanism. Deposition of woven bone occurs at sites experiencing biomechanical strains higher than those experienced by lamellar bone. In addition, woven bone in metaphyseal regions is more susceptible to osteoclastic resorption after space flight, ovariectomy, and loss of weightbearing than is lamellar bone. Finally, osteoprogenitor cells responsive to parathyroid hormone reside in the metaphyseal region of long bones. Taken together, these findings suggest that Hypothesis I represents a useful paradigm for future studies. Specific functions mediated by most individual bone and tooth matrix proteins remain uncertain. A review of current literature suggests that the functionality of skeletal matrix proteins is expressed through specific binding sites composed of particular species-conserved structural motifs (Hypothesis 2). Examples include the previously recognized Asp-Ser-Ser motif of dentin phosphophoryns and the gamma-carboxyglutamic acid motif of matrix GLA protein and osteocalcin. A new polyacidic amino acid motif composed of consecutive Asp and Glu residues (n > 7) was defined in extracellular matrix components osteopontin, bone sialoprotein, and bone acidic glycoprotein-75 on the basis of strong functional analogies with similar polyacidic stretches in divalent metal storage proteins of the endoplasmic reticulum and sarcoplasmic reticulum. These structural motifs represent prime targets for future structure-function studies in vivo and in vitro.
Estimating Application Hierarchical Bandwidth Requirements Using BSP Family Models

There has been a vast amount of work to develop programming models that provide good performance across machine architectures, are easy to use, and have predictable performance. Similarly, the design and optimization of architectures to achieve optimal performance for an application class remains a challenging task. Accurate cost modeling is essential for both application development and system design. Many scientific computing codes are developed by using libraries that provide custom-built collective communication primitives. For example, the family of Bulk Synchronous Parallel (BSP) machine models provides suitable tools for analyzing such problems. However, modeling the effect of bandwidth limitations for globally unbalanced communication and estimating the hierarchical bandwidth used by applications remain key challenges. We present a hierarchical bandwidth machine model (alpha DBSP) that naturally extends the Decomposable BSP (DBSP) model by associating a bandwidth growth factor alpha to each message pattern. Algorithms executed on alpha DBSP have a runtime that is at least as good as DBSP. Hence, there are globally unbalanced problems for which alpha DBSP analysis is simpler or more accurate We present three scientific computing kernels that illustrate the differences between alpha DBSP and DBSP analysis. Similar to the BSP family models, alpha DBSP predicts collective communication execution time for a given machine. Additionally, alpha DBSP estimates the hierarchical bandwidth required by a given application. System architects may use this estimation to design machines that avoid bandwidth bottlenecks for their target application class.
AE1: An extension matrix approximate method for the general covering problem

A new approach, the extension matrix approach, is introduced and used to show that some optimization problems in general covering problem areNP-hard. Approximate solutions for these problems are given. Combining these approximate solutions, this paper presents an approximately optimal covering algorithm,AE1. Implementation shows thatAE1 is efficient and gives optimal or near optimal results.
A novel analytical scheme to compute the n-fold convolution of exponential-sum distribution functions

A general analytical scheme for computing the n-fold convolution of exponential-sum distribution functions has been developed in this paper. The n-fold convolution is first expressed by multiple sums of recursive integrals. These recursive integrals are then reconstructed with a series of delta functions to avoid separations of integrations. Part of the recursive integrals has been solved analytically by either direct integration or with Maple-like symbolic software packages. The general analytical solution of the n-fold convolution of exponential-sum distribution functions is obtained in two steps: first developing a general pattern of Laplace transform of the recursive integrals, and then performing an inverse Laplace transform operation to the general pattern of the developed Laplace transform. The solution presented in this paper provides another option for computing the n-fold convolution of exponential-sum distribution functions.
Mechanisms of Ignition and Detonation Formation in Propane-Air Mixtures

Abstract Numerical simulations of the spontaneous ignition and subsequent detonation of propane-air mixtures caused by a weak shock in a partially confined volume containing an obstacle are performed to study potential hazards from a leaking storage container. The numerical model combines a solution of the compressible equations of fluid dynamics with a phenomenological chemical induction model for species conversion and energy release. The purpose of the simulations is to study the mechanism of the ignition and detonation processes due to shock reflections from the wall boundaries. Nonreactive simulations show how the obstacle partially blocks the flow such that one portion of the shock front reflects off of the obstacle and another portion is transmitted. Reactive-flow simulations of stoichiometric propane-air show spontaneous ignition behind the shock reflected from the obstacle and later transition to detonation in the direction of the transmitted wave. A series of computations performed to study the ...
Thyroxine-induced gill resorption in the axolotl (Ambystoma mexicanum).

Normal gill structure and thyroxine induced resorptive changes were studied in Ambystoma mexicanum. The gill is normally composed of a mesenchymal core covered with a multilayered epithelium. The general architecture is simpler than that of the teleost and elasmobranch, but the vascular arrangement is analogous. There are three basic cell types in the epithelium: a characteristic epithelial cell containing tonofibrils and mucus, a ciliated cell with an ultrastructure similar to that of the chloride cell, and the mucin-filled Leydig cell. The basal lamella and mesenchymal tissue appear typical of amphibians. Cytologic changes during thyroxine induced gill resorption varied with cell type. Some epithelial cells demonstrated a cytoplasmic response with swelling of mitochondria and rough endoplasmic reticulum and late, lytic nuclear changes, while others remained viable and went on to cornify. Ciliated cells showed early changes in nuclear chromatin pattern followed by rapid, progressive dilatation of endoplasmic reticulum. Leydig cells sustained variable changes leading to collapse of the perinuclear mucus, and cells of this type were absent in mature epidermis. Early basement membrane changes included widening and reduplication of the adepidermal membrane followed by morphologic fraying of collagen plies. There is no cytologic evidence to suggest that autolysis plays a major role in gill tissue dissolution. Resorption involved the maintenance of structural integrity in the face of diminishing physical dimensions. The epithelium became cornified, the basement lamellae dissolved, and the mesenchymal tissue was resorbed through action of macrophages in an orderly distal to proximal direction.
Hydration and percutaneous absorption: i. Influence of hydration on alkanol permeation through hairless mouse skin.

A method to study the influence of hydration on skin permeability where the skin is immersed in saline for up to 30 hr and under circumstances where a steady state rate of permeation can be established in several minutes is indicated. These circumstances allow multiple, sequential runs over a period where the permeability coefficients of some chemicals are gradually changing. It has been found that the permeabilities of water, methanol and ethanol are little affected by such hydration. However, there is a doubling of the permeability coefficients of butanol and hexanol during the first 10 hr of immersion. More hydrophobic alkanols seem to be less sensitive to the protracted aqueous conditioning. In general the results indicate that there are complex molecular structure-permeability relationships operating in skin. More specifically, the hydration effects are insightful with respect to developing barrier models for skin as they are further indications that different parallel diffusional paths are followed by polar and semi- and nonpolar species.
Surgery for stress urinary incontinence in the United States: does race play a role?

The objective of this study was to evaluate the prevalence, demographics and complications of stress urinary incontinence (SUI) surgery across races in the United States (US) in 2003. We hypothesized that there would be racial differences in surgical rates. Data from the 2003 National Census and National Hospital Discharge Survey were used. Continuous variables were tested for statistical significance by one-way analysis of variance and categorical variables by χ 2 analysis. 129,778 women underwent SUI surgery in the US in 2003, a rate of 12 surgical procedures per 10,000 women (95% CI 10–14). By race, rates (per 10,000 women, 95% CI) of SUI surgery were: ten (7–12) in white women, three (0–9) in black women, and six (0–13) in women of other races. Racial disparities in the receipt of SUI surgery may exist.
Joint time-frequency analysis of GPR data over layered sequences

Ground-penetrating radar (GPR) is widely used for interpretation of sedimentary deposits, where beds often occur in layered sequences and are often too thin to be individually resolved. Guha et al. (2005) showed that GPR traces over laminated sequences shift toward higher frequencies, and spectral analysis can be used to detect thin beds. In that study, very finely laminated sequences (well below the tuning thickness, 1/250 of dominant wavelength) were considered, and the radar frequency response was obtained using the Fourier transform. Estimating frequency response through the Fourier transform, however, does not provide information regarding the variation of frequency with time. On the other hand, joint time-frequency analysis, or JTFA, is a processing method that captures energy localization of a signal with time and allows representation of variations in spectral content of a signal in both the time and frequency domains.
A practice-then-apply scaffolding approach to engineering design education

Engineering students in a project-based curriculum are expected to learn and apply the engineering design process to their course embedded projects. Practice of embedded skills typically occurs through embarking on a new project context provided by an instructor. It is a rare occurrence for students to participate in experiences that break-up the process into smaller chunks providing low-pressure instances to practice. The following work-in-progress describes a practice-then-apply scaffolding approach to teaching engineering design. The engineering design process was broken down into three phases: (1) discovery and ideation, (2) concept development and selection, and (3) realization and experimentation. Each phase was presented to students via a mini-project that inserted students into the design process at various stages of the design. The mini-projects afforded students with opportunities to practice and expand their understanding without always having to start at the beginning. A final project embedded throughout the course provided students with the opportunity to apply what they had learned in the mini-projects. This scaffolded approach methodically slowed the process providing a unique design learning experience with explicit design activities.
1.4.3 Applying Systems Engineering Modeling Language (SysML) to System Effort Estimation Utilizing Use Case Points

This paper proposes that as model based systems engineering begins to play a larger role in system development it may be utilized in estimating systems effort, making model based systems engineering more valuable to system engineering. This paper proposes to extend the Use Case Points (UCP) estimating approach, used by some software engineers, to SysML for estimating the systems engineering effort. The paper reviews literature that encourages the notion of a UCP method for Systems Engineering (UCPSE). Finally the paper maps out the research plan to develop and validate the UCPSE method.
VM-based slack emulation of large-scale systems

This paper describes the design of a system to enable large-scale testing of new software stacks and prospective high-end computing architectures. The proposed architecture combines system virtualization, time dilation, architectural simulation, and slack simulation to provide scalable emulation of hypothetical systems. We also describe virtualization-based full-system measurement and monitoring tools to aid in using the proposed system for co-design of high-performance computing system software and architectural features for future systems. Finally, we provide a description of the implementation strategy and status of the proposed system.
Progress and Prospects on Melanoma: The Way Forward for Early Detection and Reduced Mortality

The public health problem of melanoma is difficult. Recent decades have seen substantial efforts directed at primary prevention, yet the incidence of melanoma continues to increase. Substantial efforts have been devoted to improving treatment, yet melanoma retains a poor prognosis if simple surgical excision is not curative. Early detection has made remarkable progress, however. Five-year relative survival has increased from approximately 80% in 1975 to greater than 90% in 1996. Even so, almost 8,000 Americans are projected to succumb to melanoma in 2005. Because most of these fatal melanomas are visible on the skin surface at a curable phase in their evolution, more can and must be done. To improve the early detection practices of clinicians, we have developed an eight-step Basic Skin Cancer Triage algorithm, which forms the core of a curriculum that we have shown can result in improved skills, attitudes, and practices. We are now in the process of attempting to test a Web-based version of that curriculum in a randomized trial. Skin self-examination also has tremendous potential for contributing to early detection of melanoma. We have tested an intervention to encourage thorough skin self-examination in a randomized trial and found it effective in increasing the performance of this procedure, on increase that is sustained for at least a year, while resulting in only short-term increases in surgical procedures on the skin. Early detection has not yet reached its full potential effect on the public health problem of melanoma and is poised to further reduce melanoma mortality.
Computational methods for fitting statistical distribution models of multi-site binding equilibria

Statistical distribution models of multi-site binding equilibria have potential applicability in the study of acid-base and metal complexation chemistry of humic substances in soils, sediments, and natural waters. A mathematical derivation is presented for the general continuous model for the case of proton binding; computational methods are described for fitting numerically the parameters in such models. Among models considered are those based on nontruncated, truncated, and bimodal (mixed) distributions. Specific emphasis is placed on Gaussian distribution models.
Economic Burden from Health Losses Due to Foodborne Illness in the United States

The Centers for Disease Control and Prevention (CDC) recently revised their estimates for the annual number of foodborne illnesses; 48 million Americans suffer from domestically acquired foodborne illness associated with 31 identified pathogens and a broad category of unspecified agents. Consequently, economic studies based on the previous estimates are now obsolete. This study was conducted to provide improved and updated estimates of the cost of foodborne illness by adding a replication of the 2011 CDC model to existing cost-of-illness models. The basic cost-of-illness model includes economic estimates for medical costs, productivity losses, and illness-related mortality (based on hedonic value-of-statistical-life studies). The enhanced cost-ofillness model replaces the productivity loss estimates with a more inclusive pain, suffering, and functional disability measure based on monetized quality-adjusted life year estimates. Costs are estimated for each pathogen and a broader class of unknown pathogens. The addition of updated cost data and improvements to methodology enhanced the performance of each existing economic model. Uncertainty in these models was characterized using Monte Carlo simulations in @Risk version 5.5. With this model, the average cost per case of foodborne illness was $1,626 (90%credible interval [CI], $607 to $3,073) for the enhanced cost-of-illness model and $1,068 (90%CI, $683 to $1,646) for the basic model. The resulting aggregated annual cost of illness was $77.7 billion (90%CI, $28.6 to $144.6 billion) and $51.0 billion (90%CI, $31.2 to $76.1 billion) for the enhanced and basic models, respectively.
A Low-Power Ku-Band GaAs Monolithic Frequency Quadrupler

A low-power Ku-band frequency quadrupler microwave monolithic integrated circuit was developed. Appropriate circuit design and the proposed lumped quarter wavelength stub resuted in high conversion gain and the number of drive-amplifier stages can be reduced. With this quadruplet MMIC, a low-power Ku-band local oscillator for user-portable terminals will be realized.
Comparative study of periphyton community structure in long and short-hydroperiod Everglades marshes

The Florida Everglades is a mosaic of short and long-hydroperiod marshes that differ in the depth, duration, and timing of inundation. Algae are important primary producers in widespread Everglades’ periphyton mats, but relationships of algal production and community structure to hydrologic variability are poorly understood. We quantified differences in algal biomass and community structure between periphyton mats in 5 short and 6 long-hydroperiod marshes in Everglades National Park (ENP) in October 2000. We related differences to water depth and total phosphorus (TP) concentration in the water, periphyton and soils. Long and short-hydroperiod marshes differed in water depth (73 cm vs. 13 cm), periphyton TP concentrations (172μg g−1 vs. 107 μg g−1, respectively) and soil TP (284 μg g−1 vs. 145 μg g−1). Periphyton was abundant in both marshes, with short-hydroperiod sites having greater biomass than long-hydroperiod sites (2936 vs. 575 grams ash-free dry mass m−2). A total of 156 algal taxa were identified and separated into diatom (68 species from 21 genera) and “soft algae” (88 non-diatom species from 47 genera) categories for further analyses. Although diatom total abundance was greater in long-hydroperiod mats, diatom species richness was significantly greater in short- hydroperiod periphyton mats (62 vs. 47 diatom taxa). Soft algal species richness was greater in long-hydroperiod sites (81 vs. 67 soft algae taxa). Relative abundances of individual taxa were significantly different among the two site types, with soft algal distributions being driven by water depth, and diatom distributions by water depth and TP concentration in the water and periphyton. Periphyton communities differ between short and long-hydroperiod marshes, but because they share many taxa, alterations in hydroperiod could rapidly promote the alternate community.
Division Algebras that Ramify only on a Plane Quartic Curve with Simply Connected Components

A central division algebra Λ over the field of rational functions in two variables with coefficients over an algebraically closed field ramifies along a divisor on P 2. If the ramification divisor of Λ is a quartic curve which is the union of simply connected curves, we show that Λ is a symbol algebra and satisfies the ‘index equals exponent’ equation.
Drug-free macromolecular therapeutics - a new paradigm in polymeric nanomedicines

This review highlights a unique research area in polymer-based nanomedicine designs. Drug-free macromolecular therapeutics induce apoptosis of malignant cells by the crosslinking of surface non-internalizing receptors. The receptor crosslinking is mediated by the biorecognition of high-fidelity natural binding motifs (such as antiparallel coiled-coil peptides or complementary oligonucleotides) that are grafted to the side chains of polymers or attached to targeting moieties against cell receptors. This approach features the absence of low-molecular-weight cytotoxic compounds. Here, we summarize the rationales, different designs, and advantages of drug-free macromolecular therapeutics. Recent developments of novel therapeutic systems for B-cell lymphomas are discussed, as well as relevant approaches for other diseases. We conclude by pointing out various potential future directions in this exciting new field.
Industrial Workers' Worlds: A Study of the “Central Life Interests” of Industrial Workers

In the 1955 competition for the Helen L. DeRoy Award, two papers were judged of sufficient excellence to share equally in the prize of $500. Social Problems is happy to publish both of these in the present issue. One, by Robert Dubin, appears below; the other, by Melvin Seeman, begins on page 142.
Quantification of intracoronary volume by videodensitometry: Validation study using fluid filling of human coronary casts

Changes in intracoronary volume reflect the hemodynamic significance of progression or regression of diffuse coronary artery disease where intracoronary catheters cannot be applied for direct measurements due to small vessel dimensions. We have validated the videodensitometric measurement of intracoronary volume with epoxy casts of postmortem human coronary arteries. The volume of 31 coronary segments (cross-sectional areas in a range of 2-13 mm2) measured by fluid-filling using a precision dispenser was compared with the respective single plane intracoronary volume assessments obtained by the videodensitometric algorithm of the new generation Cardiovascular Angiography Analysis System (CAAS II). The true and measured values of volume were compared by calculation of the mean of the signed differences +/- standard deviation and by linear regression analysis. Videodensitometric measurement of intracoronary volume correlate well with fluid-filling of human coronary artery casts (correlation coefficient: r = 0.99, y = 1.96 +/- 0.99x, standard error of estimate: SEE = 3.96) with a significant trend towards overestimation of true volume values (mean difference = 1.73 +/- 3.64 mm3, P < 0.05). Intracoronary volume estimations can be used to measure changes of luminal dimensions of coronary arteries and may offer a new approach to assessment of progression or regression of diffuse coronary artery disease.
Sized-based optical particle sorting using an orthogonal beam in optofluidic waveguides

We demonstrate on-chip, sized-based, optical sorting in optofluidic ARROW waveguides. Large particles are separated out of a mixture of particles of varying size as they pass through an intersecting beam.