cssi/SciSciGPT-SciSciNet huggingface dataset:
Viscoelastic tidal dissipation in giant planets and formation of hot Jupiters through high-eccentricity migration

We study the possibility of tidal dissipation in the solid cores of giant planets and its implication for the formation of hot Jupiters through high-eccentricity migration. We present a general framework by which the tidal evolution of planetary systems can be computed for any form of tidal dissipation, characterized by the imaginary part of the complex tidal Love number, Im[ ˜2(ω)], as a function of the forcing frequency ω. Using the simplest viscoelastic dissipation model (the Maxwell model) for the rocky core and including the effect of a nondissipative fluid envelope, we show that with reasonable (but uncertain) physical parameters for the core (size, viscosity and shear modulus), tidal dissipation in the core can accommodate the tidal-Q constraint of the Solar system gas giants and at the same time allows exoplanetary hot Jupiters to form via tidal circularization in the high-e migration scenario. By contrast, the often-used weak friction theory of equilibrium tide would lead to a discrepancy between the Solar system constraint and the amount of dissipation necessary for high-e migration. We also show that tidal heating in the rocky core can lead to modest radius inflation of the planets, particularly when the planets are in the high-eccentricity phase (e � 0.6) during their high-e migration. Finally, as an interesting by-product of our study, we note that for a generic tidal response function Im[ ˜2(ω)], it is possible that spin equilibrium (zero torque) can be achieved for multiple spin frequencies (at a given e), and the actual pseudosynchronized spin rate depends on the evolutionary history of the system.
Keratinizing desquamative squamous metaplasia of the upper urinary tract.

A case of keratinizing desquamative squamous metaplasia (KDSM) of the upper urinary tract is presented showing a “goblet” sign. The relationship between KDSM, cholesteatoma, and leukoplakia is discussed and conservative management is recommended.
Lipase-mediated resolution and higher-order cycloaddition of substituted tricarbonyl (η6-cycloheptatriene)chromium(0) complexes

Abstract A series of substituted cycloheptatriene-Cr(CO)3 complexes were resolved enzymatically, and the resultant chiral, non-racemic complexes underwent higher-order photocycloaddition to afford enantiomerically-enriched cycloadducts in high chemical yield.
The role of gait analysis in planning reconstructive surgery

Reconstructive surgery should restore normal structure and function to the anatomically injured body part. Therefore, it is imperative to familiarize oneself with normal gait and foot function if surgical reconstruction is undertaken. The foot is a quagmire of skin, muscles, tendons, ligaments, bones, nerves, and arteries that act as shock absorbers, load levelers, and propulsive mechanisms. When functioning normally, it can propel the human body when walking to 5 miles per hour, and when running, to 12 miles per hour. It can adapt to the vertical pressures of ballet, the horizontal forces of weightbearing on uneven terrain and even grip the narrow ledges of rock climbing. This resiliency of the foot is attributed to this complex integration of structures functioning sequentially and synchronously thousands of times per day. It truly is an underappreciated organ until pain or deformity render it useless. It has been estimated that a 150-lb person walking 1 mile generates up to 60 tons of force on each foot in normal gait. With the advent of computer-assisted gait evaluations many difficult patterns of gait have been more thoroughly analyzed. This has proved valuable in preoperative evaluation and in postoperative prosthetic and orthotic fabrication. We will attempt to outline the patterns of normal gait, normal functioning musculature, and techniques of gait analysis for the practicing plastic surgeon. Additionally the F-scan (TEKSCAN, INC., South Boston, MA) pressure measuring system will be introduced.
Discourse and the containment of disability in higher education: an institutional analysis

We use a social model of disability to examine disability discourse at a regional university in the mid-western United States. Using an institutional unit of analysis and several different information sources (e.g. interviews, federal regulations, syllabus texts, surveys), we illustrate the ways in which disability-as-difference is governed by an architecture of containment at the university.
Construct Validity of Three Types of Organizational Citizenship behavior: An Illustration of the Direct Product Model with Refinements

The direct product model is a new analysis tool for modeling multitrait-multimethod data. This model may avoid some of the problems associated with conventional analysis of multitrait-multimethod data by allowing for the possibility of multiplicative trait-method interactions. Based on the work of Browne (1984; 1990), we suggest several refinements in testing this model, including use of confirmatory procedures for testing model fit and implementation of a hierarchical approach to model comparisons. We provide an illustration of the refined direct product approach using a study of three types of organizational citizenship behavior. The results supply evidence for convergent and discriminant validity of the three constructs, and suggest that job incumbents, supervisors, and peers have significantly different perspectives of organizational citizenship behavior.
NEW CRITERIA FOR EXCHANGE OF A SPIN-ZERO MESON

The Treiman-Yang test can be extended to give a new criterion for exchange of a spin-zero particle (SZE). The new test would be useful in a reaction (e.g., ${\ensuremath{\pi}}^{\ensuremath{-}}+p\ensuremath{\rightarrow}\ensuremath{\rho}+{N}^{*}$) in which the two final systems both have a detectable polarization. For such a case it would require that the polarizations of the two systems be uncorrelated, i.e., the cross section is a product of two factors, the first depending only on the polarization of one of the final systems and the second, only on the other. The analogous statements hold for correlations connecting one of the initial particles and the final system that communicates with it only through SZE, and also for correlations connecting the two initial particles. The new test would fail in the event that more than one spin-zero particle is exchanged, i.e., the collision amplitude is a superposition of several SZE amplitudes. In that case there could be correlation terms consisting of a scalar defined in the center-of-mass-frame (c.m.) of one of the final systems (with the momentum transfer as a preferred axis) multiplied by a scalar defined in the other final c.m. If the exchanged particles do not all have the same parity, then there may be additional terms containing a pseudoscalar in the first c.m. multiplied by a pseudoscalar in the second c.m. These effects do not violate the Treiman-Yang azimuthal-angle-independence and bombardment-energy-independence tests. Furthermore, the failure of the new criterion is only partial, since a multiple SZE model continues to forbid correlations of polarization components perpendicular to the momentum transfer in their respective frames of definition.
Ferroelectric distortion in SrTiO 3 thin films on Si ( 001 ) by x-ray absorption fine structure spectroscopy: Experiment and first-principles calculations

$\mathrm{Ti}\phantom{\rule{0.3em}{0ex}}K$ and $\mathrm{Ti}\phantom{\rule{0.3em}{0ex}}{L}_{2,3}$ x-ray absorption fine-structure near-edge spectra of ${\mathrm{SrTiO}}_{3}$ thin films grown coherently on $\mathrm{Si}(001)$ reveal the presence of a ferroelectric (FE) distortion at room temperature. This unique phase is a direct consequence of the compressive biaxial strain achieved by coherent epitaxial growth.
The Lexicon of Science: A Course in Technical Terminology

The lack of a scientific background of many of our technical writing students and the continual amalgamation of the sciences make a technical terminology course an important adjunct to the technica...
Conic approximation of conic offsets

Abstract A scheme for error-bounded G 1 conic approximation of offsets to conic Bezier segments is presented. The initial step involves segmentation of the conic at points inducing cusps on the offset, ensuring that each subsegment has a smooth offset amenable to conic approximation. The approximation scheme is based on interpolating the end points and tangents, and parametric midpoint, of the exact offset. Conditions for the existence of real interpolants to such data are derived, and a sufficient condition for unambiguous definition of a distance function between the conic and its approximate offset is identified in terms of the control polygon. It is shown that extrema of this function occur along common normal lines to the conic and approximate offset, a condition satisfied at the real roots on (0,1) of a degree 10 polynomial in the conic parameter. These roots may be isolated and approximated using the Bernstein form, yielding a sharp geometric bound on the approximation error. Under subdivision the scheme produces rapidly converging approximations, satisfying any desired accuracy, for precision engineering applications.
Supplementary Energy Storage and Hybrid Front-End Converters for High-Power Mobile Mining Equipment

To supply the high-power ac-drive systems of the mining equipment, several active front ends with dc choppers are used to ensure reliable operation and an acceptable harmonic current spectrum. Recently, the integration of the energy storage system with the mining equipment has received industry attention, particularly for peak load shaving and smarter energy management of the mines. Currently, the regenerative energy is often burned into the choppers and is not fed back to the grid. The industry is motivated to capture this regenerative energy since it can be as high as 60% of the motoring power, as high as 3 MJ in every operation cycle, and as high as 24-MW peak power. Therefore, there is a possibility of large cost reductions and component rating reduction. In this paper, we investigate the operation of the current state-of-the-art front-end converter systems for multimotor applications. In particular, we propose power conversion configurations and methodology to determine the suitable energy storage technology for the development of the multimotor mobile mining equipment that has encouraging incentives for both the manufacturers and the mine operators.
Lowering extracellular calcium decreases the length of isolated outer hair cells

Abstract Transduction by the inner hair cells is hypothesized to be modulated through a change in the length of the outer hair cells (OHC). It has been suggested that the slow change occurring in OHC length is mediated by an actin-myosin system requiring Ca2+ and ATP. This study was designed to systematically examine the effects of lowering extracellular Ca2+ on OHC length. OHCs were isolated from guinea pig cochleae, mechanically dissociated and dispersed, and placed in a Hank's balanced salt solution (HBS). Exposing the cells to a Ca2+-free HBS and Ca2+-free HBS supplemented with 200 μm EDTA produced a shortening in OHC length with a concomitant increase in cell width. The shortening was reversed successfully by bathing the cells in 8 mM Ca2+. We speculate that the decrease in length due to lowering extracellular Ca2+ may be caused by a relaxation of a circumferential contractile mechanism which is thought to cause elongation of intact OHCs (Slepecky, 1989; Dulon et al., 1990).
Effect of culture in vitro with eicosatetraenoic (20:4(n-6) ) and eicosapentaenoic (20:5(n-3) ) acids on fatty acid composition, prostaglandin synthesis and chemiluminescence of rat peritoneal macrophages.

Abstract Rat peritoneal macrophages were cultured in either eicosatetraenoic acid (20:4( n − 6)) or eicosapentaenoic acid (20:5( n − 3)) and the effects on phospholipid fatty acids, prostaglandin synthesizing capacity and the ability of the macrophages to show chemiluminescence were examined. Chemiluminescence is an activity resulting from the synthesis of reactive oxygen species. It has been reported that prostaglandins inhibit this activity. The fatty acid profile of the four major phospholipids reflected the fatty acid component of the medium. Macrophages cultured in 20:4( n − 6) synthesized twice the prostaglandin produced by controls and those cultured in 20:5( n − 3) synthesized 10% that of controls and 5% that of 20:4( n − 6)-cultured cells. Macrophages cultured with 20:4( n − 6) for 12 h showed half the chemiluminescence of those cultured with 20:5( n −3), while those cultured with 20:4( n −6) for 24 h showed 10% the chemiluminescence of 20:5( n − 3)-cultured cells. Addition of the prostaglandin synthase inhibitor, indomethacin, had no effect on chemiluminescence.
The Localized Twitch Responses in Responsive Taut Bands of Rabbit Skeletal Muscle Fibers Are Related to the Reflexes at Spinal Cord Level

Objective: This study investigated spinal cord mediation of rabbit localized twitch responses [R-LTRs] by transection of the spinal cord and later of the peripheral nerve. Rabbit localized twitch response [R-LTR] is a brisk contraction of a group of rabbit skeletal muscle fibers which is most responsive to mechanical stimulation of the pressure-sensitive site, the trigger spot [TrS]. An R-LTR is analogous to a local twitch response of a human taut band, and a TrS is analogous to a human myofascial trigger point [TrP]. Methods: The electromyographic [EMG] activity of R-LTRs was recorded for the biceps femoris muscle of 5 rabbits [ages: 2-3 months]. Each animal was anesthetized in a way that preserved most peripheral reflexes. R-LTRs were elicited by mechanical-tap stimuli [delivered by a solenoid-driven blunt metal probe] to the TrS. The percentage of occurence of R-LTRs and the changes in maximal amplitude and duration of EMG activity of R-LTRs [before the spinal cord transection at T4, T5, or T6, and the...
Ionic mechanisms mediating the acetylcholine-elicited contraction in Aplysia buccal muscle

Abstract Ion channel mechanisms mediating acetylcholine (ACh)-elicited contractions in Aplysia buccal muscles were investigated using conventional force and membrane potential recording techniques and whole-cell voltage clamping of dissociated buccal muscle fibers. Previous work on buccal muscles of Aplysia showed that acetylcholine (ACh) depolarizes muscle fibers to, at most, −30 mV and that contraction is dependent upon extracellular calcium. In intact muscle, removal of either calcium or sodium from the extracellular medium reduced ACh-elicited depolarization. Absence of each ion reduced the depolarization approximately 50% at low [ACh], but at high [ACh], absence of sodium had a greater effect, while absence of calcium had a proportionally smaller effect on depolarization. Nifedipine (3 μM) reduced contraction by 50% with little accompanying change in depolarization. In whole cell voltage-clamping of isolated muscle fibers, ACh elicited an inward current at resting potential. The reversal potential for ACh-elicited current was −24±6mV. The current- voltage curve was rectified, with a bend in the inward direction near −35 mV. In zero calcium medium, ACh-elicited current averaged 54% of control, and in zero sodium medium, 42% of control. Nifedipine reduced ACh-elicited current by less than 20%. Amiloride, an inhibitor of Aplysia buccal muscle contraction, reduced ACh-elicited current by 30–70%. A model based on the above results is that ACh depolarizes muscle fibers by opening channels with a reversal potential of about —30 mV that are permeable to calcium, sodium, and at least one other ion. Depolarization activates voltage-dependent calcium channels, enabling activator calcium to enter the fibers through both ACh-operated and voltage-dependent channels.
Trimeric anilines as both donors and acceptors: an experimental and computational study

A series of donor/acceptor complexes are formed using the TTF, TCNE, and TCNQ with substituted aniline trimers in dilute acetonitrile solutions to investigate the relative success of the trimers as either electron donors or acceptors. Likewise, the effect of protonation by hydrochloric acid on the aniline trimers is investigated. Experimental results are harmonized with the results of high level density functional calculations, which reveal that trimer anilines are fascinatingly useful reagents in their own right.
Intercrystalline cracking, grain-boundary sliding, and delayed elasticity at high temperatures

The hypothesis of an interrelation between grain-boundary sliding and delayed elasticity in polycrystalline materials at high homologous temperatures is used to investigate the conditions conducive to microcracking. It is known that a material may exhibit cracking activity on attaining a critical delayed-elastic strain corresponding to a critical grainboundary sliding displacement. Experimental data on ice at temperatures >0.9Tm are used to verify this concept. The new criterion is then extended to develop simple, selfconsistent equations describing the interdependence of stress, strain, time, temperature, and grain size in predicting the onset of structural degradation due to microcracking and hence possible failure by fracture or rupture. The merit of the theory lies in its ability to forecast explicitly a large number of commonly observed high-temperature phenomena, including superplasticity, brittle-ductile transition, and the stress and temperature dependence of the apparent activation energy for fracture. One derivation makes it clear that cracking occurs when a critical stress depending only on temperature (and independent of grain size) is exceeded. The near constancy of fracture strain in the quasi brittle range can also be predicted
Reactivity of heat-treated coals in air at 500 °C

Abstract Twenty one US coals, of widely ranging rank, have been carbonized under controlled conditions to 1000 °C, and the reactivity in air at 500 °C of the resulting chars or cokes has been measured by a gravimetric method. The reactivities lie within a well-defined band when plotted against rank of the parent coal. The lower-rank coal chars are more reactive than those prepared from high-rank coals. In extreme cases, the reactivity found for a Montana lignite char is some 100 times as great as that obtained for a char produced from a Pennsylvania low-volatile coal. Variation of reactivity with heat-treatment temperature (600 to 1000 °C) has been studied for three coals. As heat-treatment temperature increases, there is a decrease in reactivity. Some results are reported on the effects which mineral matter and pore structure have on the reactivity parameter. Chars containing high concentrations of magnesium and calcium impurities are most reactive. The amount of macro and transitional porosity in a char has a marked influence on reactivity.
Estimation of entropy of melting from molecular structure : A non-group contribution method

The total entropy of melting for a variety of compounds is estimated by a modification of Walden's rule. This modification accounts for the effects of both molecular rotational symmetry and molecular flexibility upon entropy. The simple semiempirical equation gives an average error of 12.5 J/K·mol when applied to more than 930 different compounds.
Phase control of a nano-structured light-harvesting architecture

Abstract Efficient solar-energy harvesting is fundamental to solar cell technology. Much research effort has been devoted to the construction of new light-harvesting structures, including the use of semiconductor quantum dots (QDs), to improve the widespread availability of solar cells. In this research, a new light-harvesting architecture is developed, which utilizes quantum dots. The proposed architecture is composed of quantum phase-locked loops (QPLLs) to enhance the harvesting efficiency of QD solar cells by utilizing feedback control principles. The purpose of QPLL is to synchronize the phases of monochromatic light harvested by the antenna systems. This paper addresses deterministic modeling and control formulation of the QPLL within our conceptual framework. The QPLL consists of a tracking controller and a proportional–integral (PI) regulator. The QPLLs are simulated with external fluctuations to evaluate the performance of the controllers. Simulation results show that the tracking controller achieves robust and satisfactory performance. The PI regulator is more sensitive to external fluctuations and the nominal operating point. Our results demonstrate the possibility of improving light-harvesting efficiency by utilizing feedback control principles.
Protective Role of R-spondin1, an Intestinal Stem Cell Growth Factor, against Radiation-Induced Gastrointestinal Syndrome in Mice

Background Radiation-induced gastrointestinal syndrome (RIGS) results from a combination of direct cytocidal effects on intestinal crypt and endothelial cells and subsequent loss of the mucosal barrier, resulting in electrolyte imbalance, diarrhea, weight loss, infection and mortality. Because R-spondin1 (Rspo1) acts as a mitogenic factor for intestinal stem cells, we hypothesized that systemic administration of Rspo1 would amplify the intestinal crypt cells and accelerate the regeneration of the irradiated intestine, thereby, ameliorating RIGS. Methods and Findings Male C57Bl/6 mice received recombinant adenovirus expressing human R-spondin1 (AdRspo1) or E.coli Lacz (AdLacz), 1–3 days before whole body irradiation (WBI) or abdominal irradiation (AIR). Post-irradiation survival was assessed by Kaplan Meier analysis. RIGS was assessed by histological examination of intestine after hematoxilin and eosin staining, immunohistochemical staining of BrdU incorporation, Lgr5 and β-catenin expression and TUNEL staining. The xylose absorption test (XAT) was performed to evaluate the functional integrity of the intestinal mucosal barrier. In order to examine the effect of R-spondin1 on tumor growth, AdRspo1 and AdLacZ was administered in the animals having palpable tumor and then exposed to AIR. There was a significant increase in survival in AdRspo1 cohorts compared to AdLacZ (p<0.003) controls, following WBI (10.4 Gy). Significant delay in tumor growth was observed after AIR in both cohorts AdRspo1 and AdLacZ but AdRspo1 treated animals showed improved survival compared to AdLacZ. Histological analysis and XAT demonstrated significant structural and functional regeneration of the intestine in irradiated animals following AdRspo1 treatment. Immunohistochemical analysis demonstrated an increase in Lgr5+ve crypt cells and the translocation of β-catenin from the cytosol to nucleus and upregulation of β-catenin target genes in AdRspo1-treated mice, as compared to AdLacz-treated mice. Conclusion Rspo1 promoted radioprotection against RIGS and improved survival of mice exposed to WBI. The mechanism was likely related to induction of the Wnt-β-catenin pathway and promotion of intestinal stem cell regeneration. Rspo1 has protective effect only on normal intestinal tissue but not in tumors after AIR and thereby may increase the therapeutic ratio of chemoradiation therapy in patients undergoing abdominal irradiation for GI malignancies.
Comparison of haemolymph proteins from Schistosoma mansoni (trematoda)-susceptible and resistant Biomphalaria glabrata (gastropoda)

1. 1. Whole and haemoglobin (Hb)-depleted serum fractions from Schistosoma mansoni-resistant (10-R2) and schistosome-susceptible (PR albino, M-line) strains of Biomphalaria glabrata were studied using sodium dodecyl sulphate-polyacrylamide gel electrophoresis, immunoblotting and protein assays. 2. 2. Whole serum of the PR albino strain had more total protein (11.4 ± 1.9 mg protein/ml) than the 10-R2 strain (7.8 ± 3.0 mg protein/ml). 3. 3. There are specific differences in the polypeptide profiles of the Hb-depleted fractions between the 10-R2 and PR albino strains of B. glabrata. 4. 4. Antibodies against whole 10-R2 or PR albino serum reacted similarly when incubated with whole or Hb-depleted snail sera although differences in staining intensities were observed. 5. 5. Antibodies against snail Hb reacted with many proteins in whole sera and Hb-depleted fractions from both B. glabrata strains indicating that they may be Hb-associated polypeptides. 6. 6. Polypeptides in whole or Hb-depleted snail serum are modified by reduction indicating the presence of disulphide bonds.
Nitrous Acid Effect on Cleavage and Development in Fertilized Frog Eggs

NITROUS acid causes deamination of primary amino groups attached to the ring structure of nucleic acid bases; the products have been demonstrated to cause mutations in viruses1,2, bacteria3, moulds4,5 and yeasts6. Apart from a study demonstrating chromosomal fragmentation in monocotyledon root tips treated with nitrous acid7, no report of HNO2 having an effect on higher organisms has been found.
Congenital Anomalies in Offspring of Insulin-Dependent Diabetic Mothers

Congenital malformation continues to be a major problem for infants of diabetic mothers. Over a seven-year period, 199 insulin-requiring diabetic mothers were delivered at Vanderbilt University Medical Center. Con genital anomalies were identified in 26 (13%) newborns. There was no significant difference in the incidence of fetal anomalies between the various categories of White's classification of maternal diabetes mellitus. A review of proposed etiologies of anomalies in diabetic pregnancies is presented, and suggestions are made for the manage ment of women with dia betes desiring to conceive.
An adaptive estimation of periodic signals using a Fourier linear combiner

Presents an adaptive algorithm for estimating from noisy observations, periodic signals of known period subject to transient disturbances. The estimator is based on the LMS algorithm and works by tracking the Fourier coefficients of the data. The estimator is analyzed for convergence, noise misadjustment and lag misadjustment for signals with both time invariant and time variant parameters. The analysis is greatly facilitated by a change of variable that results in a time invariant difference equation. At sufficiently small values of the LMS step size, the system is shown to exhibit decoupling with each Fourier component converging independently and uniformly. Detection of rapid transients in data with low signal to noise ratio can be improved by using larger step sizes for more prominent components of the estimated signal. An application of the Fourier estimator to estimation of brain evoked responses is included. >
Optimization of multiplexed PCR on an integrated microfluidic forensic platform for rapid DNA analysis

This study reports the design, prototyping, and assay development of multiplexed polymerase chain reaction (PCR) on a plastic microfluidic device. Amplification of 17 DNA loci is carried out directly on-chip as part of a system for continuous workflow processing from sample preparation (SP) to capillary electrophoresis (CE). For enhanced performance of on-chip PCR amplification, improved control systems have been developed making use of customized Peltier assemblies, valve actuators, software, and amplification chemistry protocols. Multiple enhancements to the microfluidic chip design have been enacted to improve the reliability of sample delivery through the various on-chip modules. This work has been enabled by the encapsulation of PCR reagents into a solid phase material through an optimized Solid Phase Encapsulating Assay Mix (SPEAM) bead-based hydrogel fabrication process. SPEAM bead technology is reliably coupled with precise microfluidic metering and dispensing for efficient amplification and subsequent DNA short tandem repeat (STR) fragment analysis. This provides a means of on-chip reagent storage suitable for microfluidic automation, with the long shelf-life necessary for point-of-care (POC) or field deployable applications. This paper reports the first high quality 17-plex forensic STR amplification from a reference sample in a microfluidic chip with preloaded solid phase reagents, that is designed for integration with up and downstream processing.
cAMP Regulates Cell Proliferation and Cyst Formation in Autosomal Polycystic Kidney Disease Cells

Both epithelial cell proliferation and fluid accumulation are responsible for cyst growth in autosomal dominant polycystic kidney disease (ADPKD). It was previously reported that the cystic fibrosis transmembrane conductance regulator (CFTR) is expressed in cysts from ADPKD patients and suggested that cAMP-stimulated Cl(-) and fluid secretion occurs through CFTR. The purpose of this study was to investigate the role of cell proliferation in cyst formation in ADPKD and to explore further the role of fluid secretion in cyst growth. Primary cultures both of ADPKD epithelial cells and a mixed population of normal renal epithelial cells isolated from the cortex (HRCE cells) were used. This study tested whether cAMP was involved both in stimulating cell proliferation and formation of cysts in vitro. (3)H-Thymidine incorporation assays showed that epidermal growth factor stimulated proliferation both in ADPKD cells and HRCE cells. In addition, cAMP stimulated DNA synthesis and cell proliferation in ADPKD, but not HRCE, cells. The effects of cAMP and epidermal growth factor on cell growth in ADPKD cells were additive. cAMP also stimulated cyst enlargement and fluid secretion in ADPKD cells. By contrast, cyst formation and enlargement from HRCE cells occurred without cAMP. Fluid secretion into the cyst lumen was blocked by diphenylamine carboxylic acid (DPC) and glibenclamide in ADPKD cells but blocked only by DPC in HRCE cells. This study showed that ADPKD cells have unique characteristics; cAMP stimulates fluid secretion and cell proliferation, indicating cAMP plays a very important role in cyst growth during the course of ADPKD.
Lethal and sub-lethal effects of UV-B radiation exposure on the collembolan Folsomia candida (Willem) in the laboratory

Abstract This study assessed the effects of UV-B irradiation on the physiology, life history, DNA, and behavior of the blind non-pigmented soil-dwelling collembolan Folsomia candida (Willem). In three sets of controlled laboratory studies, adult F. candida were reared in darkness and exposed to light with no UV-B (filtered), low UV-B or high UV-B (weighted irradiance energy of 3.12 mW/m 2 and 22.1 mW/m 2 , respectively). Study I investigated UV-B impacts on mortality, egg viability, and egg development time of F. candida under continual exposure. Study II assessed the movement patterns, mortality, egg production and fecundity of adult F. candida in response to UV-B exposure within choice environments. Study III determined the degree of UV-B induced DNA damage (thymine dimer formation) on F. candida and subsequent DNA repair. Continuous irradiation resulted in increased mortality, under high and low UV-B conditions compared to controls. Consistent with other studies on the impact of light on collembola, we found that F. candida avoided light when given the option. Though preferring darkness, animals were more likely to venture into lighted regions with no UV-B (filtered) and experienced higher mortality rates than in regions with high or low UV-B. Eggs were laid preferentially in the dark, with fewer total eggs observed in the habitat with the highest UV-B. We further demonstrated that UV-B induced the formation of thymine dimers in a dose dependent manner. DNA repair was not evident in animals that had returned to the dark after a brief intense UV-B irradiation. These findings indicate that UV-B exposure and exposure to longer wavelengths of light has both lethal and sub-lethal effects on F. candida that can adversely affect its survival.
A Generalization of the Terwilliger Algebra

Abstract P. M. Terwilliger (1992, J. Algebraic Combin.1, 363–388) considered the C -algebra generated by a given Bose Mesner algebra M and the associated dual Bose Mesner algebra M*. This algebra is now known as the Terwilliger algebra and is usually denoted by T. Terwilliger showed that each vanishing intersection number and Krein parameter of M gives rise to a relation on certain generators of T. These relations determine much of the structure of T, thought not all of it in general. To illuminate the role these relations play, we consider a certain generalization T of T. To go from T to T , we replace M and M* with a pair of dual character algebras C and C*. We define T by generators and relations; intuitively T is the associative C -algebra with identity generated by C and C* subject to the analogues of Terwilliger's relations. T is infinite dimensional and noncommutative in general. We construct an irreducible T -module which we call the primary module; the dimension of this module is the same as that of C and C*. We find two bases of the primary module; one diagonalizes C and the other diagonalizes C*. We compute the action of the generators of T on these bases. We show T is a direct sum of two sided ideals T 0 and T 1 with T 0 isomorphic to a full matrix algebra. We show that the irreducible module associated with T 0 is isomorphic to the primary module. We compute the central primitive idempotent of T associated with T 0 in terms of the generators of T .
The network as knowledge : Generative rules and the emergence of structure

The imputation problem is how to account for the sources of the value of the firm. I propose that part of the value of the firm derives from its participation in a network that emerges from the operation of generative rules that instruct the decision to cooperate. Whereas the value of firm-level capabilities is coincidental with the firm as the unit of accrual, ownership claims to the value of coordination in a network pit firms potentially in opposition with one another. We analyze the work on network structure to suggest two types of mechanisms by which rents are distributed. This approach is applied to an analysis of the Toyota Production System to show how a network emerged, the rents were divided to support network capabilities, and capabilities were transferred to the United States. Copyright © 2000 John Wiley & Sons, Ltd.
Sex Differences in the Developmental Origins of Cardiovascular Disease

The Developmental Origins of Health and Disease (DOHaD) proposes that adverse events during early life program an increased risk for cardiovascular disease. Experimental models provide proof of concept but also indicate that insults during early life program sex differences in adult blood pressure and cardiovascular risk. This review will highlight the potential mechanisms that contribute to the etiology of sex differences in the developmental programming of cardiovascular disease.
Automatic scene relighting for video conferencing

This paper describes a new method to automatically improve scene lighting for video conferencing by learning the photometric mapping between a lower exposure and desired exposure created using High Dynamic Range (HDR) imaging techniques. Once the mapping is learned in a calibration step, it can be used to transform all subsequent images, effectively producing higher dynamic range video without ghosting artifacts. A stereo algorithm is also described that allows multiple exposures to be taken at every frame, useful if the lighting of a scene changes significantly. Results show that this is an effective way to improve face lighting and therefore the overall experience of video conferencing.
Operationalizing DSM-IV criteria for PMDD: selecting symptomatic and asymptomatic cycles for research.

Abstract While diagnostic criteria for premenstrual syndromes (PMS) exist, studies rarely state how these criteria are operationally applied. We examined the consequences of application of different operational methods for DSM-IV criteria for premenstrual dysphoric disorder (PMDD) to individual cycles in women with PMS and controls. PMDD criteria require the presence of both certain types or numbers of symptoms (5/11 symptoms present premenstrually, at least one being one of four mood symptoms) and certain phenomenal characteristics (present premenstrually, absent postmenstrually, causing interference premenstrually). We identified individual cycles as symptomatic or asymptomatic by applying criteria that operationalized the required phenomenal elements of PMDD according to four severity thresholds: literal (i.e. present or absent), 30%, 50%, 70%. Data examined were Daily Rating Form symptom scores from two symptomatic menstrual cycles both in 25 women with PMS and 25 controls. Literal thresholds correctly identified 28% of symptomatic and 4% of asymptomatic cycles, compared with 86 and 70% identification with a 30% threshold, 60 and 86% with a 50% threshold, and 0 and 100% with a 70% threshold. An “optimal” combination of 30% thresholds for premenstrual symptomatology and premenstrual interference and a 50% threshold for postmenstrual symptomatology correctly identified 92% of symptomatic cycles in women with PMS and 72% of asymptomatic cycles in controls. Different criteria for cycle inclusion yield markedly different sample compositions. No single operational threshold of the phenomenal features maximizes selection of both symptomatic and asymptomatic cycles, largely consequent to the ubiquity of postmenstrual symptoms and premenstrual “interference” even in women without PMS. At the very least, the method for operationalizing DSM-IV criteria should be described in studies of PMDD.
Fabrication of coated bovine serum albumin (BSA)-epigallocatechin gallate (EGCG) nanoparticles and their transport across monolayers of human intestinal epithelial Caco-2 cells.

The bovine serum albumin (BSA)–epigallocatechin gallate (EGCG) nanoparticles were fabricated using a desolvation method, and coated with poly-e-lysine or chitosan. BSA–EGCG nanoparticles (BEN), poly-e-lysine coated BSA–EGCG nanoparticles (PBEN), and chitosan coated BSA–EGCG nanoparticles (CBEN) had a spherical morphology and a size of 186, 259, and 300 nm, respectively. The loading efficiency of EGCG in these nanoparticles was 32.3%, 35.4%, and 32.7%, whereas the loading capacity was 18.9%, 17.0%, and 16.0% (w/w), respectively. Poly-e-lysine or chitosan coating prevented the aggregation of nanoparticles at pH 4.5–5.0. However, they caused particle aggregation at pH 6.5–7.0. BEN had negative zeta-potentials between pH 4.5 and 6.0. Poly-e-lysine or chitosan coating changed the zeta-potentials to positive. The release study of EGCG from the nanoparticles in the simulated gastric or intestinal fluid with or without digestive enzymes showed that poly-e-lysine and chitosan coatings delayed EGCG release from the nanoparticles. Poly-e-lysine or chitosan coating improved the stability of EGCG during storage at 60 °C compared with EGCG in the uncoated particles. EGCG in BEN, PBEN, and CBEN had a decreasing apparent permeability coefficient (Papp) on Caco-2 monolayers, whereas pure EGCG showed relatively stable Papp during the incubation over time. EGCG in CBEN showed significantly higher Papp, suggesting that chitosan coated BSA–EGCG nanoparticles may improve the absorption of EGCG.
Gastric Cancer Prevention by Demethylation

Niwa and colleagues report in this issue that treatment with the DNA demethylation agent 5-aza-2'-deoxycytidine decreases the incidence of gastric cancers in an animal model of Helicobacter pylori-promoted gastric cancer. This provocative study underscores the importance of changes in DNA methylation that contribute to the origin of inflammation-related cancers. The findings also raise the exciting possibility of cancer prevention by altering DNA methylation events early during tumorigenesis.
Effect of grain size on the monoclinic transformation, hardness, roughness, and modulus of aged partially stabilized zirconia.

Abstract Objective Low-temperature-degradation (LTD) has been reported to cause property changes in yttria-tetragonal zirconia polycrystals (Y-TZP). The current study measured monoclinic phase transformation of Y-TZP with different grain sizes and corresponding property changes due to artificial aging. Null hypothesis: the grain size of aged Y-TZP will not influence its transformation, roughness, hardness or modulus of elasticity. Methods Four groups of Y-TZP were examined with differing grain sizes ( n = 5). The line intercept technique was used to determine grain sizes on SEM images (100,000×). Artificial aging was accomplished by autoclaving at 2 bar pressure for 5 h. X-ray diffraction (30 mA, 40 kV) was used to measure tetragonal to monoclinic transformation (t → m). Surface roughness analysis was performed using a non-contact surface-profilometer. Nano-hardness and modulus of elasticity were measured using nano-indentation. Results SEM analyses showed different grain sizes for each sample group (0.350 μm, 0.372 μm, 0.428 μm, and 0.574 μm). The fraction of t → m transformation increased as grain size increased; furthermore, aging of zirconia caused increased roughness. Modulus and hardness after aging displayed no significant correlation or interaction with grain size. Significance Smaller grains caused less transformation, and aging caused increased roughness, but grain size did not influence the amount of increased surface roughness. Future studies are needed to determine the effects of grain size on the wear and fracture properties of dental zirconia.
Harmonization of assistive technology standards

Assistive technology provides people with disabilities the means to perform many activities with minimal or no assistance. Standards for assistive technology vary across countries and among technologies. Variation in standards among technologies is to be expected, due to the differences with which the devices interact with the user and the intimacy of the contact. Standards differ across countries for two fundamental reasons: mandatory standards are a means of controlling trade; and national standards often grow from a local need. Harmonization attempts to create standards that are applied equally across all member countries. The ISO is the leading standardization institution on a world-wide basis. Most assistive devices are within the purview of Technical Committee 173 (TC-173) and its subcommittees. The subcommittees of TC-173 are responsible for specific areas of assistive technology. The subcommittees are comprised of participants from the member countries that have specific expertise related to the standard(s) being developed. In the area of assistive technology, participants come from clinical professions (e.g. physical medicine, physical therapy, occupational therapy), engineering (e.g. rehabilitation engineering, bioengineering, test engineering), manufacturing, test laboratories, regulatory bodies and users of assistive technology. Harmonization should bring about higher-quality products that are more widely available.
Investigating Radio Frequency Identification (RFID) for Linear Asset Management

Linear assets including roads, pipelines, and railroad tracks are defined assets whose lengths play a critical role in their maintenance. Linear assets, along with their features, which include traffic lights, number of lanes, speed limits, guardrails, and highway billboards, are hard to physically access and, therefore, update inventory information files that were previously captured. To address this problem, some transportation agencies are investigating technologies that will assist in solving this asset inventory problem. The primary focus of this paper is to evaluate the feasibility of using radio-frequency identification (RFID) technology as a means of gathering, verifying, and storing information for linear assets. The study investigates confluence factors that affect the performance of RFID. The factors investigated include driving speed and tag location on signposts, delineators, and guardrails. The results indicate that for the three vehicle speeds tested (10 mph, 20 mph, 30 mph), tag readability decreased with an increase in speed.
Fifty (or More) Ways to Leave Your Platelets (in a Thrombus)

With a nod to Paul Simon, there may be more ways to activate platelets than there were ways to leave your lover in his song from the 70’s—or at least it seems that way. Gas6 is a vitamin K–dependent, protein-S–related protein found in the α-granules of resting platelets. Once platelet activation has occurred, Gas-6 appears in the fluid phase and on the platelet surface, where it presumably becomes bound after secretion. In this issue of Arteriosclerosis, Thrombosis, and Vascular Biology , Chen et al show that platelets express at least one of the known receptors for Gas-6, the receptor tyrosine kinase, Mer.1 According to their observations, deletion of the gene encoding Mer in mice does not produce an overt bleeding phenotype or even prolong the bleeding time, but it does inhibit platelet aggregation, diminish the thrombotic response to vascular injury, and provide some protection against disseminated thrombosis.1 These effects are less profound, but qualitatively similar to those reported several years ago by Angelillo-Scherrer et al in their studies on mice that lack Gas6,2 and essentially similar to those they have subsequently reported in abstract form using mice that lack either Mer or two related receptors, Axl and Rse (also known as Sky).3 See page 1118 Gas6 is a 75-kDa protein with several distinct structural domains, starting with an N-terminal domain that includes γ-carboxylated glutamic acid (Gla) residues, a central domain with epidermal growth factor (EGF) repeats and two C-terminal G domains responsible for receptor binding and activation.4,5 Gla residues are glutamic acid residues that have undergone vitamin K–dependent γ-carboxylation, allowing them to support Ca++-dependent binding to phosphatidylserine. Like the Mer knockout, the Gas6 knockout causes decreased secretion and impairs platelet aggregation, particularly at low agonist concentrations. It also provides some degree of protection …
IL-13-induced Clara cell secretory protein expression in airway epithelium: role of EGFR signaling pathway

Previous work showed that the Th2 cytokine interleukin (IL)-13 induces goblet cell metaplasia via an indirect mechanism involving the expression and subsequent activation of epidermal growth factor...
Haematological, neurological and electrocardiographic findings in secondary hypothermia.

The association between secondary hypothermia and pancytopaenia is uncommon. A young woman presented with chronic hypothermia (28.8–34.6°C) secondary to surgical hypothalamic injury postcraniopharyingioma resection as a child. Associated findings included pancytopaenia (haemoglobin 8.1 g/dl, leucocytes 3500/mm3, platelets 63 000/mm3), ataxia, upper motor neuron signs, decreased level of consciousness and new ECG changes. An extensive evaluation failed to reveal any cause of pancytopaenia other than chronic hypothermia. The haematological and neurological changes improved after active rewarming.
Model Assessment and Selection in Multiple Regression

Regression, as a scientific method, first appeared around 1885, although the method of least squares was discovered 80 years earlier. Least squares owes its origins to astronomy and, specifically, to Legendre’s 1805 pioneering work on the determination of the orbits of planets in which he introduced and named the method of least squares. Adrien Marie Legendre estimated the coefficients of a set of linear equations by minimizing the error sum of squares. Gauss stated in 1809 that he had been using the method since 1795, but could not prove his claim with documented evidence. Within a few years, Gauss and Pierre Simon Laplace added a probability component — a Gaussian curve to describe the error distribution — that was crucial to the success of the method. Gauss went on to devise an elimination algorithm to compute least-squares estimates. Once introduced, least squares caught on immediately in astronomy and geodetics, but it took 80 years for these ideas to be transported to other disciplines.