cssi/SciSciGPT-SciSciNet huggingface dataset:
Simultaneous presentation of moving objects in an infant tracking task

The results of Bower, Broughton, and Moore (1971) indicate that tracking behavior in infants under the age of 16 weeks is disrupted by changes of motion, but not by changes of features of the objects in motion. These results and those of related studies ( Bower, 1974 ) have led to the hypothesis that the young infant neither attends to the features nor is aware that what she/he perceives is an object. The present study modifies the structure of the tracking task to allow a simultaneous, rather than a successive presentation of stimulus objects. Twenty-four infants from 10–15 weeks of age were tested in a tracking task with a bull's-eye sphere and a checkerboard cube. Results clearly indicate that infants between 10 and 16 weeks of age are capable of attending to featural characteristics of moving objects. Measures of visual regard show a clear infant preference for the cube over the sphere.
A Method to Estimate Off-Schedule Observations in a Longitudinal Study

Purpose Data in epidemiological studies sometimes are collected off-schedule from planned study visits. In an ancillary study to the Study of Women’s Health Across the Nation (SWAN), longitudinal breast density data were collected retrospectively from mammograms that were not acquired at the study visits. We propose a method to estimate the off-schedule breast density measurements at the time of study visits. Methods This method uses local linear interpolation, with multiply imputed error terms drawn from assumed subject-specific normal distributions based on the within-subject standard deviations of mammographic density measurements. We evaluate the validity and implications of this approach. Results Coefficients of random intercept models used to assess the association between annual changes in body mass index and dense breast area estimated with this approach (β = −0.17, p = .46) differed from those obtained when each mammogram was matched to the nearest study visit (β = −0.30, p = .04). The proposed estimation approach had a small average prediction error (0.11 cm2). Conclusions Because matching does not incorporate breast density changes over time, our local linear interpolation with multiple imputation approach may provide more accurate results. The proposed approach is applicable to other epidemiologic studies with off-schedule data in which the missing variable changes linearly over relatively short periods of time.
Numerical Analysis of Time-Dependent Inelastic Deformation in Metallic Media Using the Boundary-Integral Equation Method

A numerical analysis procedure using the boundary-integral equation method is presented for the solution of problems of time-dependent inelastic deformation in planar metallic bodies. The formulation allows the use of both classical creep theories in the absence of time-independent plasticity as well as newer theories of inelastic deformation using state variables. Numerical results are presented for plane stress problems using either the power law equations of creep or the state variable theory due to Hart. Comparison of BIE and analytical methods for simple problems shows good agreement. Other features of the numerical solutions of more complicated problems are discussed in the paper.
A Usability Survey at the University of Mississippi Libraries for the Improvement of the Library Home Page

A usability survey was conducted at the University of Mississippi Libraries as part of the ongoing assessment of the library and its services. By setting criteria to measure the success of the survey, librarians at UM were able to assess if the library home page successfully met the goals and mission statement of the library.
Vector squeezed states

We study a two-mode squeezed state of the electromagnetic field, in which each mode is degenerate in frequency, but they have orthogonal polarizations. We use a degenerate four-wave-mixing geometry and two-photon transitions for these squeezed states. The modes are treated in a mean-field approximation that includes the effects of vacuum fluctuations. Material parameters of sodium vapor and the semiconductor CuCl are used to illustrate the results.
Increasing the odds: applying emergentist theory in language intervention.

Purpose This review introduces emergentism, which is a leading theory of language development that states that language ability is the product of interactions between the child’s language environme...
Predicting soil sorption coefficients of organic chemicals using a neural network model

The soil/sediment adsorption partition coefficient normalized to organic carbon (Koc) is extensively used to assess the fate of organic chemicals in hazardous waste sites. Several attempts have been made to estimate the value of Koc from chemical structure or its parameters. The primary purpose of this study was to develop a nonlinear model for estimating Koc applicable to polar and nonpolar organics based on artificial neural networks using the octanol/water partition coefficient (Kow) and water solubility (S). An analytic equation was obtained by starting with a neural network, converging the bias and weight values using the available data on water solubility, octanol/water partition coefficient, and the normalized soil/sediment adsorption partition coefficient, and then combining the equations for each node in the final neural network. For the 119 chemicals in the training set, estimates using the neural network equation lie outside the 2σ region (the standard deviation for the training set, σ = 0.52) for only five chemicals, while all the chemicals in the test set lie within the 2σ region. It was concluded that the neural network equation outperforms the linear models in fitting the Koc values for the training set and predicting them for the test set.
Extending the chinchilla middle ear epithelial model for mucin gene investigation.

Objectives: To investigate the expression of recently identified human mucin genes in an in vivo model of the chinchilla middle ear epithelium (CMEE). Methods: CMEE was harvested, RNA was extracted and primers were designed for RT-PCR to assess for expression of mucin genes Muc6, Muc17 and Muc18. Further sequencing of these genes was also accomplished. Results: Mucin genes Muc6, Muc17 and Muc18 was assessed and found to be identical to the expression in human and mouse MEE. Conclusion: This study further characterizes mucin gene expression in the CMEE and provides additional sequence data for chinchilla middle ear genes. The concordance of this gene expression data to that of both the human and mouse models further demonstrates the utility of this animal model in OM investigations.
Anti-IL6R Attenuates Humoral Responses to Allograft in a Mouse Model of Allosensitization

Purpose The role IL-6 plays in transplant rejection has been increasingly recognized, therefore, targeting the IL-6/IL-6R pathway may have applications in treatment of allograft rejection. This study evaluated the efficacy of a mousenized rat-anti-mouse IL-6R mAb, mMR16-1, in suppressing alloantibody responses. Methods and Materials C57BL/6 mice were sensitized with skin allografts from a HLA.A2 transgenic mouse, and treated with intraperitoneal injections of mMR16-1 or control antibody. Donor specific antibody (DSA) responses were monitored weekly for 5 weeks by measurement of serum anti-HLA.A2 antibodies in a flow cytometric antibody binding assay. Results mMR16-1 significantly reduced DSA responses to skin allograft, resulting in significant decreases of anti-HLA.A2 IgM (treated vs. control: 12.7+2.3 MFI vs. 22.9+3.2 MFI at day 14, p=0.00022), IgG2a (99.41 +35.31 MFI vs. 300.6+53.04 MFI at day 28, p=6.621E-05) and IgG1 (25.6+9.8 MFI vs. 40.01+7.7 MFI at day 28, p=0.029), respectively. Anti-IL6R treatments also normalized serum amyloid A (SAA), an acute phase reactant induced by IL-6 (p Conclusions The data indicate that antibody therapy targeting the IL-6/IL-6R pathway may serve as a strategy to suppress DSA generation. Future mechanistic studies to dissect various cellular compartments targeted by anti-IL-6R in the alloimmunity will shed more light on our understanding of the therapeutic properties of anti-IL-6R on rejection suppression.
Kinetics of SiO vapor ammonolysis for nano-sized silicon nitride powder synthesis☆

Abstract The kinetics of SiO vapor ammonolysis to produce nano-sized silicon nitride powder was studied with an 80-mm-diameter vertical tubular flow reactor operated at temperatures ranging from 1300 °C to 1400 °C. The molar feed rate of NH3 was maintained 2–3 orders of magnitude in excess of stoichiometric ratio over SiO. The rate of reaction to form nano-sized powder was represented by a pseudo-first-order rate expression with respect to SiO concentration, independently of NH3 concentration. The temperature dependency of the pseudo-first-order rate constant was determined. The effects of mean residence time as well as the reaction temperature on the growth of nano-sized particles were investigated, and the minimum residence time to produce particles of critical size was estimated.
Theoretical frameworks in qualitative research

The true value of this publication is its offering readers the opportunity for a glimpse of how scholars have successfully identified and applied theoretical frameworks in their research.
Status Consistency and Merton's Modes of Individual Adaptation*

(1968). Status Consistency and Merton's Modes of Individual Adaptation. The Sociological Quarterly: Vol. 9, No. 4, pp. 531-539.
Long-term annual water balance analysis of the Lena River

Abstract Historical data analyses show that the Lena River and its major tributaries experienced an extended low water period over 1936–1957 and high water periods over 1974–1983 and 1988–2001. Higher than normal river discharge and annual precipitation is particularly pronounced since the late 1960s due to large-scale changes in atmospheric circulation patterns. The trend in runoff observed in the Lena River basin increased by 10% from 1936 to 2001 due to extended wet periods during the second part of last century. The trend is weakened for the Vilui River basin since it experiences reservoir regulation, which causes additional water losses through reservoir filling and increased evaporation. Runoff regulation strongly affects the winter runoff regime of both the Vilui River and the lower reaches of the Lena River causing an increased winter discharge at the Lena river outlet station of approximately 33%.
A new model for rheumatoid arthritis generated by engraftment of rheumatoid synovial tissue and normal human cartilage into scid mice

Objective. A new animal model was used to study the interaction between rheumatoid synovial cells and cartilage and to explore the cellular basis of rheumatoid joint destruction. Methods. Fresh synovial tissue derived from patients with rheumatoid arthritis was implanted with normal human cartilage into SCID mice, either subcutaneously or under the renal capsule, for up to 304 days. The implants were analyzed by light and electron microscopy, as well as by immunohistochemistry and in situ hybridization. Results. Human synovial tissue and cartilage implanted in SCID mice are maintained by the animals for up to 304 days. After 35 days, focal erosions occur at the site of attachment of synovial lining cells to the cartilage. After 105 days, a pannus-like formation, consisting of proliferating synovial fibroblast-like cells invading the cartilage, is observed. The fibroblast nature of these cells was supported by observation of only focal expression of the macrophage markers CD14 and CD68. Cells at the immediate site of cartilage destruction express messenger RNA for cathepsin L, whereas cathepsin D messenger RNA was detected in subsynovial regions away from the site of destruction. The human origin of the tissue involved in cartilage destruction was demonstrated using monoclonal antibodies to HLA-ABC and human type IV collagen. Conclusion. The present approach introduces a novel in vivo model of rheumatoid arthritis for the study of the molecular and cellular mechanisms of rheumatoid joint destruction at sites of synovial attachment to cartilage. In this model, the SCID mouse acts as a useful host for studying the properties of rheumatoid synovium in the absence of circulating human blood components.
A new class of murine retroviruses: Immunological and biochemical comparison of novel isolates from Mus cervicolor and Mus caroli

A new murine retrovirus (designated M432) isolated from the Southeast Asian mouse species, Mus cervicolor, has been characterized with respect to its protein composition, RNA genome, and certain of its immunologic properties. The M432 virus contains a magnesium-dependent reverse transcriptase (MW 70,000) and at least five other viralassociated proteins (MW.s 65,000, 32,000, 24,000, 16,000, and 12,000). The two largest structural proteins (designated gp65 and gp32) are glycosylated and are components of the virion surface. The major internal protein is p24, while p12 is the major viral phosphoprotein. A radioimmunoassay developed for the p24 protein detects this antigen in cultured cells infected with M432 as well as in tissues of animals from the species Mus musculus which were inoculated at birth with the M432 virus. A second retrovirus (designated M832) isolated from cultured cells of another Southeast Asian murine species, Mus caroli, is related by several criteria to the M432 virus. An antiserum to the polymerase of M432 cross-reacts with the reverse transcriptase of M832; similarly, the radioimmunoassay for the M432-p24 protein detects a cross-reactive antigen in cells producing M832. Using nucleic acid hybridization techniques, a partial sequence homology (∼25%) can be detected between the RNA genomes of the two new isolates. By morphologic, immunologic, and biochemical criteria, the M432 and M832 viruses are unrelated to known type C and type B viruses isolated from mice and appear, then, to be members of a new class of genetically transmitted murine retroviridae.
Subduction hinge migration along the Izu-Bonin-Mariana Arc

Abstract Hinge migration or “rollback” is thought to have a significant influence on the tectonics of trench-arc-backarc systems. Where the backarc region is actively opening, the hinge is usually either stationary or retreating in a mantle (hotspot) frame of reference. The Izu-Bonin-Mariana system represents a highly anomalous case in which the hinge is reportedly advancing behind the retreating eastern edge of the overriding Philippine Sea plate. We have re-evaluated the motion of the subduction hinge using the best available estimates of the motion of the Philippine Sea plate and estimated maximum rates of extension within the Izu-Bonin Arc: if the plate motions have not changed appreciably, the subduction hinge of the Izu-Bonin Trench has advanced over the last 5 Ma. The approximate average rate of hinge advance is 0–6 mm a−1 at the north end of the Izu-Bonin Arc, increasing to 24–30 mm a−1 at 27°N. The rate of advance of the Mariana hinge (at 18°N) is 10–20 mm a−1. The dip of the subducted slab is strongly correlated with the motion of the Philippine Sea plate, suggesting that the rapid retreat of the overriding plate affects mantle flow. We have found a tentative hinge-advance mechanism in a simple Newtonian-viscous corner flow model. Though the model has severe geometrical and rheological limitations, it suggests that the retreat of the overriding plate gives rise to excess uplift pressures acting on the top surface of the subducted slab. If the hinge is not assumed to be fixed, the excess pressure will tend to rotate the slab arcward, steepening the slab and advancing the subduction hinge. Thus, the westward motion of the Philippine Sea plate may explain both the advance of the subduction hinge and the observed relationship between the motion of the Philippine Sea plate and the dip of the subducted slab along the Izu-Bonin-Mariana Trench.
Arrangements on chessboards

Abstract For the study of the distribution of like objects on chessboards, i.e., rectangular arrays of square cells, with no lines (rows or columns) of the boards empty, the enumerators Ar, s(t) = ∑tmA(m; r, s) of r by s rectangles by number of objects, defined by (1+t) xy ∑ r,s=0 ( x r )( y s )A r,s (t) are shown to hold a central position. Their properties and uses are examined at length.
LIFE-CYCLE COST ANALYSIS FOR ZINC AND OTHER PROTECTIVE COATINGS FOR STEEL STRUCTURES

Life-cycle cost models for corrosion-protection coating systems for structural steel are presented. The models are a first-construction/replacement model and a rehabilitation model considering a finite service life and perpetual service. The model development considered comparison period, price and service lives, interest rate, inflation and taxes, and sensitivity and risk analysis. Mathematical expressions are presented for the models. A Virginia bridge superstructure example is presented for painting versus a galvanized coating system considering a 75-year design life. The example illustrates the cost-effectiveness of selecting the galvanized coating system over paint for an environmental exposure condition in Virginia.
Experiential Effects On Agonistic Behavior in the Paradise Fish, Macropodus Opercularis

The effects of prior dominance experience on agonistic behavior were investigated in male paradise fish, Macropodus opercularis, with particular reference to the social conditioning hypothesis. The subjects had only limited social experience prior to the pre-test treatments; their pre-test dominance histories were controlled experimentally, through rigged contests (based on relative size). Following the pre-test conditioning treatments, the treated fish were paired with naive siblings of the same standard length, and subjected to a battery of four tests: two measures of aggressiveness, one of reactivity and one of social dominance. The latter consisted of a dyadic encounter with a naive sibling in a neutral aquarium. Four separate experiments were conducted, each exploring a different parameter of social dominance. It was found that negative dominance experience resulted in a significant decrement in subsequent dominance success and in increased reactivity levels, but had no influence on the measures of aggressiveness. Positive dominance experience had no effect on any of the response measures. The implications of the asymmetry in the effects of dominance experience (particularly with regard to subsequent dominance scores) for the social conditioning hypothesis and the associationist paradigm in general, as it applies to agonistic behavior, were explored. It was concluded that the social conditioning hypothesis cannot account for the results obtained here or for those of related studies. The relationships between the measures of aggressiveness and the measure of social dominance were also discussed.
Explaining moral religions

Moralizing religions, unlike religions with morally indifferent gods or spirits, appeared only recently in some (but not all) large-scale human societies. A crucial feature of these new religions is their emphasis on proportionality (between deeds and supernatural rewards, between sins and penance, and in the formulation of the Golden Rule, according to which one should treat others as one would like others to treat oneself). Cognitive science models that account for many properties of religion can be extended to these religions. Recent models of evolved dispositions for fairness in cooperation suggest that proportionality-based morality is highly intuitive to human beings. The cultural success of moralizing movements, secular or religious, could be explained based on proportionality.
Translations of commutative unique factorization semigroups

Every commutative semigroup is a semilattice of archimedean subsemigroups. Given a semilattice Y and a collection of commutative semigroups S indexed by Y, the converse problem of constructing every commutative semigroup which is a semilattice (Y) of the semigroups S remains unsolved except in certain cases. If each S is an abelian group the result follows as a special case of Clifford's Theorem (see [33, Thm. 4.11). The authors [13 have given a solution for any semilattice where each S is assumed to be cyclic, and more recently, Tamura has solved the problem for exclusive semilattices of exclusive semigroups [63 For a characterization of the general semilattice decomposition when each Se is weakly reductive, see Theorem 7.8.13 of [41. An element x of a commutative semigroup S is said to be prime if x ~ S 2 . S is said to have unique factorization if each nonzero element of S can be written uniquely as a product of primes in the usual sense. A commutative semigroup has unique factorization if and only if it is free or a Rees quotient of a free commutative semigroup (E2~, Thm. i). Commutative nil unique factorization semigroups were used in the characterization of arbitrary commutative nil semigroups in [11 (see [53 for an alternate characterization). Since commutative unique factorization semigroups arise naturally in the general theory of commutative semigroups, it seems of interest
50 &#937; Log-periodic monopole array with modulated-impedance microstrip feeder

It is demonstrated theoretically and experimentally that a log-periodic monopole array with a meander-line feeder may be expected to exhibit high values of voltage standing-wave ratio. Improved match can be obtained by allowing the impedance of the feeder to go to a higher value near each monopole. A good match to 50 \Omega is achieved in this way.
Hybrid phased array for improved internal auditory canal imaging at 3.0‐T MR

Purpose To develop and evaluate a hybrid phased array for internal auditory canal (IAC) imaging at 3.0 T. Materials and Methods A hybrid phased array was designed and built as two circular surface receive-only coils combined with a volume transmit-receive birdcage head coil for simultaneous image acquisition. Phantom and volunteer images were obtained to assess the coil performance. Results The phantom data show that significant signal-to-noise ratio (SNR) improvement was achieved in the region corresponding to the inner ear, i.e., by a factor of 2.5 compared to the standard head coil data. Volunteer IAC image quality was deemed superior as compared to images acquired at 3.0 T using a standard head coil. Conclusion This hybrid array combined with three-dimensional fast spin-echo (FSE) acquisition resulted in improved high spatial resolution IAC imaging. J. Magn. Reson. Imaging 2002;16:300–304. © 2002 Wiley-Liss, Inc.
Dental surgery versus dental medicine

The author’s justification for the use of the DDS degree rather than the DMD degree. Traditionally, he says, surgeons have been those who used manual and operative procedures in treating illness, and these are the procedures that are emphasized in dental education and practice today.
An experimental and theoretical investigation of the influence of alkene homo energy level upon the hydroboration reaction. Additional evidence supporting an early transition state which has retention of alkene character.

Abstract The effects of some substituents upon the hydroboratlon with 9~BBN of alkenes were examined. The ordering of the energy levels of the pi MO's correlates with that of the relative reactivities of the alkenes toward hydroboration: a higher MO energy level corresponds to a higher relative reactivity. The regioselectivity of boron—carbon bond formation correlates with a.o. coefficient size In the alkene HOMO.
AutoEmotive: bringing empathy to the driving experience to manage stress

With recent developments in sensing technologies, it's becoming feasible to comfortably measure several aspects of emotions during challenging daily life situations. This work describes how the stress of drivers can be measured through different types of interactions, and how the information can enable several interactions in the car with the goal of helping to manage stress. These new interactions could help not only to bring empathy to the driving experience but also to improve driver safety and increase social awareness.
Parochial Libraries: Compiling a Directory, and its Aftermath

Abstract A short account of the background and origin of the 1959 report on parochial libraries is followed by particulars of the scope, sources, methodology, and field trip experiences of the revi...
Effect of dexamethasone on rat plasma platelet activating factor acetylhydrolase during the perinatal period

It has been previously reported that the administration of dexamethasone (DEX) to adult rats increases the activity of plasma platelet-activating factor acetylhydrolase (PAF-AH) and prevents the development of intestinal necrosis caused by platelet activating factor (PAF) injection. In this report, we examined the effect of DEX administration on plasma PAF-AH activity during the perinatal period. Timed-pregnant rats received DEX (0.2–1.0 mg/kg/d) or normal saline (controls) on days 16–18 (early group) or days 18–20 (late group) of gestation. Maternal plasma PAF-AH activity was lower in late gestation than in postpartum period (P < 0.001). Fetal and neonatal plasma PAF-AH activity was higher than maternal values (P < 0.05). No changes of PAF-AH activity were seen in maternal, fetal or neonatal plasma after prenatal DEX administration at the aforementioned doses. A higher dose of DEX (1.3 mg/kg/d × 4d) or cortisone (200 mg/kg/d) produced an elevation of maternal plasma PAF-AH activity (DEX 79.2 ± 3.0, cortisone 70.5 ± 1.9 vs. controls 49.4 ± 2.3 nmol/min/ml, P < 0.01), but resulted in a high fetal mortality. Treatment of newborn rats with DEX (0.5 mg/kg/d) on days 1–3 after birth, increased plasma PAF-AH activity on day 4 (DEX 292 ± 5 versus controls 140 ± 9 nmol/min/ml, P < 0.001) and day 6 (DEX 302 ± 12 versus controls 136 ± 6 nmol/min/ml, P < 0.001). Postnatal administration of DEX increases the plasma PAF-AH activity in the rat. Only high doses of prenatal corticosteroids that cause fetal death can elevate maternal plasma PAF-AH activity.
Efficient generation of bright XUV high-order harmonics beyond 22 eV at 50 kHz repetition rate

We report a bright high-repetition rate XUV source, where 48 μJ second-harmonic pulses of a 50-kHz Ti:sapphire amplifier focused into Kr gas drive high-harmonic generation at 22.3 eV with >10−5 efficiency despite a tight-focusing geometry.
An Infinite Product for e

(1980). An Infinite Product for e. The American Mathematical Monthly: Vol. 87, No. 5, pp. 391-391.
Medical student electives in general surgical subspecialties.

Background: The purpose of the study was to evaluate how well the burn, trauma, and peripheral vascular third-year medical school electives meet the objectives of the six ACGME core competencies. Methods: Medical school graduates from 1999 to 2002 completed a survey that consisted of 13 demographic/miscellaneous questions, and 28 core competency questions. Results: In all, 168 of 500 students responded for a 34% response rate. All three general surgical electives ranked above average in meeting objectives in the areas of: basic science, performing complete histories and physicals, writing logical and legible notes, creating complete assessments and plan, making decisions with evidence based medicine, performing basic procedures, interpreting test results, and maintaining professional attitudes. The burn elective ranked significantly higher in 16 of 28 objectives (P <0.05) and the trauma elective ranked significantly higher in two of 28 objectives (P <0.05). Conclusions: Despite a narrower professional focus, three general surgical subspecialty electives meet objectives in five of the six competencies set forth by the ACGME (and adopted by our medical school as objectives for the ideal graduate). The highly organized and structured burn elective can be used as a template for improving all surgical rotations to meet the six core competencies for third-year students.
The Politics of Rescue: Yugoslavia's Wars and the Humanitarian Impulse

Pasic and Weiss examine the limitations and the ethical dilemmas of the humanitarian impulse in light of the recent surge in humanitarian intervention. The authors use the experience of the United Nations High Commissioner for Refugees in the former Yugoslavia as an example of the way in which politics and humanitarianism are inextricably intertwined. They describe a spectrum of intervention, from rescue to restorative to revolutionary efforts. Rescue efforts often fail to address the underlying political problems, but for a rescuing nation to commit to “revolutionary” intervention and sustained support raises the issue of state sovereignty. Asserting that humanitarian intervention is a highly ambiguous principle, the authors warn of the dangers of politically driven rescues that often force trade-offs between the pursuit of rescue and political order.
A nonmetric approach to measurement: an application to pattern representation

A nonmetric-nonstatistical method for representing an N-point configuration is presented as an alternative to metric methods such as using Cartesian coordinates. The advantages of a nonmetric basis include the ability to use sensors (measurements) of poor rather than high quality by substituting novel computational algorithms to offset sensor inaccuracy. An outline of this approach to measurement is presented and supported by computer simulation results. The simulations illustrate a nonnumeric encoding and recovery of geometric pattern information and also furnish interesting insights into human vision. >
Assembly of the Cleavage and Polyadenylation Apparatus Requires About 10 Seconds In Vivo and Is Faster for Strong than for Weak Poly(A) Sites

We have devised a cis-antisense rescue assay of cleavage and polyadenylation to determine how long it takes the simian virus 40 (SV40) early poly(A) signal to commit itself to processing in vivo. An inverted copy of the poly(A) signal placed immediately downstream of the authentic one inhibited processing by means of sense-antisense duplex formation in the RNA. The antisense inhibition was gradually relieved when the inverted signal was moved increasing distances downstream, presumably because cleavage and polyadenylation occur before the polymerase reaches the antisense sequence. Antisense inhibition was unaffected when the inverted signal was moved upstream. Based on the known rate of transcription, we estimate that the cleavage-polyadenylation process takes between 10 and 20 s for the SV40 early poly(A) site to complete in vivo. Relief from inhibition occurred earlier for shorter antisense sequences than for longer ones. This indicates that a brief period of assembly is sufficient for the poly(A) signal to shield itself from a short (50- to 70-nucleotide) antisense sequence but that more assembly time is required for the signal to become immune to the longer ones (approximately 200 nucleotides). The simplest explanation for this target size effect is that the assembly process progressively sequesters more and more of the RNA surrounding the poly(A) signal up to a maximum of about 200 nucleotides, which we infer to be the domain of the mature apparatus. We compared strong and weak poly(A) sites. The SV40 late poly(A) site, one of the strongest, assembles several times faster than the weaker SV40 early or synthetic poly(A) site.
Tomographic Velocity Estimation With Planewave Synthesis Imaging

In areas with structurally complex geology, tomographic velocity analysis is required to estimate velocities. This paper describes a tomographic velocity analysis algorithm which uses planewave synthesis imaging as a prestack migration. In reflection tomography, prestack migration is required for both event picking and traveltime error computation. Traveltime errors are often measured in the form of residual moveout (RMO) velocity in common surface location (CSL) gathers after prestack depth migration. It is shown that we can measure the residual moveout (RMO) velocity accurately with the help of reflector-dependent planewave synthesis imaging.
Media Effects Theory and the Nature/Nurture Debate: A Historical Overview and Directions for Future Research

In this article, I provide a historical overview of the nature/nurture debate by exploring the philosophical history of the debate leading up to the inception of media effects research. I argue that the media effects tradition was born into a milieu that was exclusively sided with the nurture (environmental determinist) position and has largely remained so. Within the past 20 years, there have been advances in neurophysiology leading other disciplines to theorize that human behavior is the result of the interaction between nature (genetics, brain physiology) and nurture (learning, culture). In this article, I sample the media effects research emerging from this perspective and argue why this approach is superior to the learning-only approach currently popular in the field of communication. I then discuss the implications of such an approach for communication researchers, framing the critique in terms of the contribution to mass communication theory building. A frequent lunch discussion topic at a recent International Communication Association conference was DeFleur’s (1998) article about the current lack of “milestone” research in mass communication, research that “provoked wide discussion and changed the way that scholars think about the mass communication process” (p. 86). DeFleur suggested a number of reasons for this state of affairs including a
Leonardo da Vinci's contributions to neuroscience

Leonardo da Vinci (1452-1519) made far-reaching contributions to many areas of science, technology and art. Leonardo's pioneering research into the brain led him to discoveries in neuroanatomy (such as those of the frontal sinus and meningeal vessels) and neurophysiology (he was the first to pith a frog). His injection of hot wax into the brain of an ox provided a cast of the ventricles, and represents the first known use of a solidifying medium to define the shape and size of an internal body structure. Leonardo developed an original, mechanistic model of sensory physiology. He undertook his research with the broad goal of providing physical explanations of how the brain processes visual and other sensory input, and integrates that information via the soul.
Statistical analysis of a nonlinear estimator for ADC and its application to optimizing diffusion weighting factors

In this paper, we develop a model for estimating the accuracy of a nonlinear estimator used in estimating the apparent diffusivity coefficient (ADC) which provides useful information about the structure of tissue being imaged with diffusion weighted MR. Further, we study the statistical properties of the nonlinear estimator and use them to design optimal diffusion weighting factors. Specifically, we show that a weighted linear estimator can well approximate the nonlinear estimator and thus can be used to analyze the statistical properties of the nonlinear estimator. Furthermore, to account for the fact that the ground truth of the ADC is a distribution instead of a single value, a weighted coefficient of variance (COV) is proposed as a criteria to be minimized for the determination of the optimal diffusion weighting factors. Both synthetic and real experiments are shown to depict the performance of our approach.
“Efficiency Space”: A Framework for Evaluating Joint Evaporation and Runoff Behavior*

AbstractAt the land surface, higher soil moisture levels generally lead to both increased evaporation for a given amount of incoming radiation (increased “evaporation efficiency”) and increased runoff for a given amount of precipitation (increased “runoff efficiency”). Evaporation efficiency and runoff efficiency can thus be said to vary with each other, motivating the development of a unique hydroclimatic analysis framework. Using a simple water balance model fitted, in different experiments, with a wide variety of functional forms for evaporation and runoff efficiency, the author transforms net radiation and precipitation fields into fields of streamflow that can be directly evaluated against observations. The optimal combination of the functional forms—the combination that produces the most skillful streamflow simulations—provides an indication for how evaporation and runoff efficiencies vary with each other in nature, a relationship that can be said to define the overall character of land surface hydr...
Use of Simplified Flow Separation Criteria for Slotted Flap Preliminary Design

From experimental correlations of airfoil and flap pressure distributions, it is observed that flow separation is likely to occur when the canonical pressure recovery coefficient (C sub pr) exceeds a critical value. A procedure is described for obtaining the C sub pr parameter from modified inviscid analysis. The procedure has been applied to preliminary design studies of a new slotted flap to determine the influence of shape and location. Experiments are planned to evaluate the flap designed by this procedure.
Fast block data processing via a new IIR digital filter structure

A new structure for realizing IIR digital filters is introduced based on the idea of processing sequences by blocks. It is shown that this structure exhibits high inherent parallelism that is ideally suited for VLSI implementation or multimicroprocessor systems. This enables high-speed processing with the number of multiplies and additions per output sample much less than those of the block-state or canonical filter realizations. The roundoff noise level in the output of the new filter structure is derived and compared to the noise levels of the block-state and canonical forms. Further, it is shown that the new filter structure will present no scaling problems if the canonical filter is scaled. Finally, the extension of the new filter structure to the realization of periodically time-varying digital filters is also presented.
Measuring transnational leakage of forest conservation

Abstract Forest conservation in one country can influence the degree of conservation or deforestation in other countries because of international linkages of the forest products industry and markets and a lack of global coordination. Thus leakage and offsetting losses of environmental quality may be present. This paper develops an analytical framework for measuring this leakage and estimates its magnitude via general equilibrium modeling. We find that the magnitude of leakage depends upon the price elasticities of supply of and demand for forestry products across the countries and degree of cooperation in forest conservation. We estimate that a significant portion (42%–95%) of the reduced forestry production implemented in a country/region can be transferred to elsewhere, offsetting environmental gains. Leakage generally diminishes as more countries cooperate, but cooperation among only a few countries does not always dramatically reduce leakage. Thus forest conservation efforts and associated environmental quantity gains in a country or group of countries can be seriously undermined in terms of global net conservation gain in the absence of effective global cooperation. Our results also point to the importance of taking leakage into account in evaluating local or regional forest carbon sequestration projects.
Utilization of the Mating Scaffold Protein in the Evolution of a New Signal Transduction Pathway for Biofilm Development

ABSTRACT Among the hemiascomycetes, only Candida albicans must switch from the white phenotype to the opaque phenotype to mate. In the recent evolution of this transition, mating-incompetent white cells acquired a unique response to mating pheromone, resulting in the formation of a white cell biofilm that facilitates mating. All of the upstream components of the white cell response pathway so far analyzed have been shown to be derived from the ancestral pathway involved in mating, except for the mitogen-activated protein (MAP) kinase scaffold protein, which had not been identified. Here, through binding and mutational studies, it is demonstrated that in both the opaque and the white cell pheromone responses, Cst5 is the scaffold protein, supporting the evolutionary scenario proposed. Although Cst5 plays the same role in tethering the MAP kinases as Ste5 does in Saccharomyces cerevisiae, Cst5 is approximately one-third the size and has only one rather than four phosphorylation sites involved in activation and cytoplasmic relocalization. IMPORTANCE Candida albicans must switch from white to opaque to mate. Opaque cells then release pheromone, which not only induces cells to mate but also in a unique fashion induces mating-incompetent white cells to form biofilms that facilitate opaque cell mating. All of the tested upstream components of the newly evolved white cell pheromone response pathway, from the receptor to the mitogen-activated protein (MAP) kinase cascade, are the same as those of the conserved opaque cell response pathway. One key element, however, remained unidentified, the scaffold protein for the kinase cascade. Here, we demonstrate that Cst5, a homolog of the Saccharomyces cerevisiae scaffold protein Ste5, functions as the scaffold protein in both the opaque and the white cell pheromone responses. Pheromone induces Cst5 phosphorylation, which is involved in activation and cytoplasmic localization of Cst5. However, Cst5 contains only one phosphorylation site, not four as in the S. cerevisiae ortholog Ste5. These results support the hypothesis that the entire upper portion of the newly evolved white cell pheromone response pathway is derived from the conserved pheromone response pathway in the mating process.
Dielectric relaxation in composites containing electrically isolated particles with thin semi-continuous metal coatings

The dielectric relaxation due to interfacial charges in metal particle-filled composites occurs in the optical (high frequency) regime. However, many applications would benefit from a shift of the relaxation to a much lower frequency regime (e.g. radio or microwave range). This could be achieved by using a filler with reduced conductivity, but there is no continuum of conductivity in naturally occurring materials to allow engineers to readily achieve this aim or to have complete design freedom. Recently, it was demonstrated, experimentally and theoretically, how insulating particles with nano-scale metal coatings enable this relaxation to be shifted to a lower frequency regime. The current work investigates the microstructure of the metal coating, highlighting a semi-continuous coating structure. Therefore, the relevance of a two-dimensional (2D) percolation-based model to describe the effective dielectric properties of the coating is explored. It is demonstrated that a model in which the metal coating is assumed to be near the 2D percolation threshold can provide a reasonable fit to the experimental data. An improved fit is achieved when a distribution of metal area coverage is permitted.
Clinical Trials in Cancer Prevention: Current Results and Perspectives for the Future

Cancer prevention remains the ideal strategy for reducing the burden of cancer on society. Progress in cancer prevention has been accelerated as prevention clinical trials are completed and reported. A promising strategy is the identification of cancer risk factors through epidemiologic and experimental research with lifestyle and medical approaches that allow translation of clinical trial results to clinical practice. A major focus of cancer prevention clinical trials has been on modulation of hormones and nutritional modifications using natural or synthetic bioactive food components for breast and prostate cancer. Breast cancer prevention clinical trials have investigated the role of estrogen antagonists with agents such as tamoxifen, raloxifene, and newer agents such as aromatase inhibitors and bioactive food components. Among the promising bioactive food components being investigated at the National Cancer Institute in prevention clinical trials to reduce breast cancer risk are indole-3-carbinol, sulforaphanes, phytoestrogen isoflavones, perillyl alcohol, and green tea polyphenols. Prostate cancer prevention trials have focused on hormone modulation with the 5-alpha-reductase inhibitor finasteride and bioactive food components such as selenium and vitamin E. Soy isoflavones, green tea polyphenols, and doxercalciferol also are being investigated for prostate cancer prevention. Future prevention clinical trials will rely on multidisciplinary medical approaches that bring together expertise in many fields to address disease across the cancer spectrum. Nutritional science can play an important role in this effort through the use of new and emerging technologies to better understand the influence of bioactive food components on the genes, proteins, and cellular processes that are associated with cancer risk.
Communication Technology Adoption and Ethnicity

ABSTRACT A national telephone survey was conducted to examine differences in communication technology adoption across Whites, Blacks, and Hispanics and identify adoption predictors based on demographics, media use, and perceptions of new technologies for each ethnic group. Results revealed few ethnic variations in individual communication technologies penetration. Even after controlling for socioeconomic variables, ethnicity remained a significant source of influence on communication technology adoption. Although income was the only common predictor in the adoption regressions within each ethnic group, perceived relative advantage of new technologies and household size were also important determinants for White and Black respondents.
CONTEMPORARY EVOLUTION OF SEA URCHIN GAMETE‐RECOGNITION PROTEINS: EXPERIMENTAL EVIDENCE OF DENSITY‐DEPENDENT GAMETE PERFORMANCE PREDICTS SHIFTS IN ALLELE FREQUENCIES OVER TIME

Species whose reproductive strategies evolved at one density regime might be poorly adapted to other regimes. Field and laboratory experiments on the sea urchin Strongylocentrotus franciscanus examined the influences of the two most common sperm-bindin alleles, which differ at two amino acid sites, on fertilization success. In the field experiment, the arginine/glycine (RG) genotype performed best at low densities and the glycine/arginine (GR) genotype at high densities. In the laboratory experiment, the RG genotype had a higher affinity with available eggs, whereas the GR genotype was less likely to induce polyspermy. These sea urchins can reach 200 years of age. The RG allele dominates in larger/old sea urchins, whereas smaller/younger sea urchins have near-equal RG and GR allele frequencies. A latitudinal cline in RG and GR genotypes is consistent with longer survival of sea urchins in the north and with predominance of RG genotypes in older individuals. The largest/oldest sea urchins were likely conceived at low densities, before sea-urchin predators, such as sea otters, were overharvested and sea-urchin densities exploded off the west coast of North America. Contemporary evolution of gamete-recognition proteins might allow species to adapt to shifts in abundances and reduces the risk of reproductive failure in altered populations.