cssi/SciSciGPT-SciSciNet huggingface dataset:
The development of an appreciation of specific linkages between linguistic and conceptual organization

Abstract Evidence from infants and toddlers, and from preschool children learning either English, French, or Spanish as their first language are summarized to reveal the emergence of specific linkages between linguistic and conceptual development. The data suggest that infants begin the process of word learning with a general expectation that words (independent of the linguistic form) refer to objects and object categories. This initial, rudimentary linkage gives way to more specific pairings between particular linguistic forms (e.g., nouns vs. adjectives) and particular types of meaning (e.g., object categories vs. properties of objects). These more specific linkages may depend upon language experience.
Dynamic Synapse: A New Concept of Neural Representation and Computation

Presynaptic mechanisms influencing the probability of neurotransmitter release from an axon terminal, such as facilitation, augmentation, and presynaptic feedback inhibition, are fundamental features of biological neurons and are cardinal physiological properties of synaptic connections in the hippocampus. The consequence of these presynaptic mechanisms is that the probability of release becomes a function of the temporal pattern of action potential occurrence, and hence, the strength of a given synapse varies upon the arrival of each action potential invading the terminal region. From the perspective of neural information processing, the capability of dynamically tuning the synaptic strength as a function of the level of neuronal activation gives rise to a significant representational and processing power of temporal spike patterns at the synaptic level. Furthermore, there is an exponential growth in such computational power when the specific dynamics of presynaptic mechanisms varies quantitatively across axon terminals of a single neuron, a recently established characteristic of hippocampal synapses. During learning, alterations in the presynaptic mechanisms lead to different pattern transformation functions, whereas changes in the postsynaptic mechanisms determine how the synaptic signals are to be combined. We demonstrate the computational capability of dynamic synapses by performing speech recognition from unprocessed, noisy raw waveforms of words spoken by multiple speakers with a simple neural network consisting of a small number of neurons connected with synapses incorporating dynamically determined probability of release. The dynamics included in the model are consistent with available experimental data on hippocampal neurons in that parameter values were chosen so as to be consistent with time constants of facilitative and inhibitory processes governing the dynamics of hippocampal synaptic transmission studied using nonlinear systems analytic procedures.
Rhabdomyosarcoma of the bile ducts

Rhabdomyosarcoma is a rare malignant neoplasm of the biliary tract. Including all the historical recent probable, and established cases that are carefully classified by Hayes and Synder, only 24 cases have been reported to date. Because of the extreme rarity of this tumor in this location, correct diagnosis was not made until second laparotomy or autopsy in several reported cases. The present report describes a child who recently underwent excision of such a tumor at our institution.
Synchronization of two Lorenz systems using active control

Abstract Using techniques from active control theory, we demonstrate that a coupled Lorenz system can be synchronized. The synchronization is verified using the Simulink feature in MATLAB.
Work conjugacy error in commercial finite-element codes: its magnitude and how to compensate for it

Most commercial finite-element programs use the Jaumann (or co-rotational) rate of Cauchy stress in their incremental (Riks) updated Lagrangian loading procedure. This rate was shown long ago not to be work-conjugate with the Hencky (logarithmic) finite strain tensor used in these programs, nor with any other finite strain tensor. The lack of work-conjugacy has been either overlooked or believed to cause only negligible errors. Presented are examples of indentation of a naval-type sandwich plate with a polymeric foam core, in which the error can reach 28.8 per cent in the load and 15.3 per cent in the work of load (relative to uncorrected results). Generally, similar errors must be expected for all highly compressible materials, such as metallic and ceramic foams, honeycomb, loess, silt, organic soils, pumice, tuff, osteoporotic bone, light wood, carton and various biological tissues. It is shown that a previously derived equation relating the tangential moduli tensors associated with the Jaumann rates of Cauchy and Kirchhoff stresses can be used in the user’s material subroutine of a black-box commercial program to cancel the error due to the lack of work-conjugacy and make the program perform exactly as if the Jaumann rate of Kirchhoff stress, which is work-conjugate, were used.
Distinct Characteristics of Inferonasal Fundus Autofluorescence Patterns in Stargardt Disease and Retinitis Pigmentosa

Purpose. To report distinct characteristics of fundus autofluorescence (AF) patterns inferior to the optic disc in recessive Stargardt disease (STGD1) and retinitis pigmentosa (RP).
Thyroid hormone receptor subtype specificity for hormone-dependent neurogenesis in Xenopus laevis

Abstract Thyroid hormone (T3) influences cell proliferation, death and differentiation during development of the central nervous system (CNS). Hormone action is mediated by T3 receptors (TR) of which there are two subtypes, TRα and TRβ. Specific roles for TR subtypes in CNS development are poorly understood. We analyzed involvement of TRα and TRβ in neural cell proliferation during metamorphosis of Xenopus laevis. Cell proliferation in the ventricular/subventricular neurogenic zones of the tadpole brain increased dramatically during metamorphosis. This increase was dependent on T3 until mid-prometamorphosis, after which cell proliferation decreased and became refractory to T3. Using double labeling fluorescent histochemistry with confocal microscopy we found TRα expressed throughout the tadpole brain, with strongest expression in proliferating cells. By contrast, TRβ was expressed predominantly outside of neurogenic zones. To corroborate the histochemical results we transfected living tadpole brain with a Xenopus TRβ promoter-EGFP plasmid and found that most EGFP expressing cells were not dividing. Lastly, treatment with the TRα selective agonist CO23 increased brain cell proliferation; whereas, treatment with the TRβ-selective agonists GC1 or GC24 did not. Our findings support the view that T3 acts to induce cell proliferation in the tadpole brain predominantly, if not exclusively, via TRα.
The synaptonemal complex of Meloidogyne nataliei and its relationship to that of other Meloidogyne species

The four synaptonemal complexes (SC) in Meloidogyne nataliei (n=4) have normal, tripartite morphology, although the total width of the SC is only 50 nm. Each SC is attached at both ends to the nuclear envelope and there is no bouquet formation at pachytene. Pairing of homologues is regular but not complete, as there is one region on each bivalent where the SC is not formed. This region may be the ‘fusion point’ of telomeres of nonhomologous chromosomes, since it is assumed that M. nataliei has been derived from an ancestral strain (n=8) via chromosomal fusions. In each pachytene nucleus there is a nonmembranous, vacuole-like structure of unknown function located in the nucleoplasm adjacent to the nucleolus, and of approximately the same volume as the nucleolus. The fact the SC structure of M. nataliei is strikingly different from that of most Meloidogyne species suggest that M. nataliei may not belong to the same phyletic group as the genus Meloidogyne.
Simulations of Stretching Single Stranded DNA

Molecular dynamics simulations were performed to estimate sequence dependent force required to stretch single stranded DNA (ssDNA) homo oligonucleotides. Simulations suggest that polyA and polyC oligonucleotides exhibit similar force profiles and corresponding elongation. Among single stranded DNA strands polyT is the most flexible and needs the most force to unwind from an equilibrium folded structure. In contrast, polyG had a very small recoverable deformation prior to a non-linear stretching. Our results indicate that mechanical properties of ssDNA chains are directly related to their sequence.
Computations of Nonrelativistic Electron Bremsstrahlung

Highly accurate computations of the total intensity of bremsstrahlung have been performed on the New York University UNIVAC using both Sommerfeld's result and the Born approximation as modified by Elwert. The incident electron energy range treated was from 0.44 ev to 80 kev, together with a large range of emergent electron energies so as to cover the range of emitted frequencies. The results are presented graphically such that they may be obtained to an accuracy of better than 1.0%.
Suppression of Island Formation During Initial Stages of Ge/Si(100) Growth by Ion-Assisted Molecular Beam Epitaxy

We have observed a suppression of island formation and an increase in the thickness limit for layer-by-layer growth of Ge on Si (100) by ion-assisted molecular beam epitaxy. Island suppression is observed both for ion energies at which surface defect generation dominates bulk defect generation and at which the majority of defects generated are bulk defects. This experiment, in conjunction with results of a linear elastic stability model for islanding, reveals that the kinetic mechanism for the suppression of island formation via ion bombardment is the reduction of surface amplitude fluctuations during the early stages of growth.
Review of Selected Adjuvants Used in Antibody Production.

Immunologic adjuvants are agents that nonspecifically increase immune responses to specific antigens that are weakly immunogenic. The purpose of this article is to inform investigators and research staff about three commonly used and commercially available adjuvants for antibody production in laboratory animals and to briefly cover other adjuvants that may be used for this purpose. The three adjuvants that will be emphasized in this article are Freund's-type mineral oil adjuvant emulsions, Ribi Adjuvant System®, and TiterMax®. Other reports have studied these adjuvants, or combinations thereof, when administered with specific antigens (Lipman et al., 1992; Smith et al., 1992; Johnston et al., 1991). The objective of using adjuvants differs greatly, whether in research, antisera production, or vaccine development. Adjuvants intended for production of antisera need to induce high titers of high avidity antibody within a short time. Adjuvants intended for vaccine use need only induce protective titer, although the duration of the response and induction of immunologic memory are critical for maintaining protection. Induction of cell-mediated immunity is a requirement for protection against many etiologic agents, but is also partly responsible for side effects of adjuvants. Adjuvants or immunopotentiators were initially thought of as agents capable of promoting an augmented and more sustained antibody response. However, new evidence has shown that adjuvants influence titer, duration, isotype, and avidity of antibody, as well as affect properties of cell-mediated immunity (CMI) (Table 1) (Hunter et al., 1995). For example, adjuvants have been shown to induce class I-restricted CD8-positive cytotoxic T lymphocytes and modulate the specificity of antibody among available epitopes on protein antigens (Takahashi et al., 1990; Kenney et al., 1989). Adjuvants can be categorized according to their origins (whether they are derived from mineral; bacterial; plant; synthetic; or host product, such as Interleukin 1 and 2), and according to their proposed mechanism of action. Certain adjuvants such as alum, oil emulsions, liposomes, and synthetic polymers act through the effect of antigen localization ("depot" effect), which leads to slow delivery of the antigen. Most adjuvants also induce complex cell interactions between macrophages and lymphocytes.
The political economy of American industrialization, 1877-1900

In the late nineteenth century, the United States underwent an extremely rapid industrial expansion that moved the nation into the front ranks of the world economy. At the same time, the nation maintained democratic institutions as the primary means of allocating political offices and power. The combination of robust democratic institutions and rapid industrialization is rare and this book explains how development and democracy coexisted in the United States during industrialization. Most literature focuses on either electoral politics or purely economic analyses of industrialization. This book synthesizes politics and economics by stressing the Republican party's role as a developmental agent in national politics, the primacy of the three great developmental policies (the gold standard, the protective tariff, and the national market) in state and local politics, and the impact of uneven regional development on the construction of national political coalitions in Congress and presidential elections.
Energy group structure determination using particle swarm optimization

Abstract Multi-group theory is widely applied for the energy domain discretization when solving the Linear Boltzmann Equation. To reduce the computational cost, fine group cross libraries are often down-sampled into broad group cross section libraries. Cross section data collapsing generally involves two steps: Firstly, the broad group structure has to be determined; secondly, a weighting scheme is used to evaluate the broad cross section library based on the fine group cross section data and the broad group structure. A common scheme is to average the fine group cross section weighted by the fine group flux. Cross section collapsing techniques have been intensively researched. However, most studies use a pre-determined group structure, open based on experience, to divide the neutron energy spectrum into thermal, epi-thermal, fast, etc. energy range. In this paper, a swarm intelligence algorithm, particle swarm optimization (PSO), is applied to optimize the broad group structure. A graph representation of the broad group structure determination problem is introduced. And the swarm intelligence algorithm is used to solve the graph model. The effectiveness of the approach is demonstrated using a fuel-pin model.
Nitrate reductase activity and nitrogenous gas evolution from heterotrophic, photomixotrophic and photoautotrophic soybean suspension cultures

Abstract Soybean ( Glycine max L. Merr. cv. Corsoy) suspension cultures were grown hetertrophically (3% sucrose, dark), photomixotrophically (1% sucrose, light), and photoautotrophically (no sucrose, light) to determine if constitutive and inducible nitrate reductase (NR) activities were expressed (both activities are expressed in intact plants). Nitrogenous gas evolution, a marker for the constitutive activity in soybean leaves, was not detected in any of the cultures at any time during the 14-day subculture period. Moreover, photomixotrophic and heterotrophic cells grown on glutamine as a nitrogen source had no detectable NR. Cells grown on nitrate contained NR activity with an apparent K m (NO 3 − ) identical to that of the inducible activity from soybean leaves, and glutamine did not express this activity. It was concluded that constitutive NR was not expressed in soybean suspension culture regardless of age, nitrogen source, or photosynthetic capability, while inducible NR activity was expressed with nitrate nutrition. The implications of these findings, in terms of using suspension cultures to select NR deficient soybean lines for possible regeneration, are discussed.
Bilateral bicolored irides with Hirschsprung's disease. A neural crest syndrome.

• A syndrome in which bicolored irides and congenital megacolon were the sole manifestations occurred in three Mexican siblings. Analysis of the pedigree suggested an autosomal recessive mode of inheritance. A neural crest defect may be the basis of this and related syndromes.
CW laser machining of hard ceramics—I. Effects of three-dimensional conduction, variable properties and various laser parameters

Abstract A three-dimensional conduction model has been developed to predict the temperature distribution inside the solid and the shape of a groove formed by partial evaporation of a semi-infinite body using a moving CW laser with a Gaussian beam profile. This has application in laser machining where material is removed by repeated scanning of a focussed beam on the workpiece surface. The governing equations are solved using a finite-difference method on an algebraically-generated boundary-fitted coordinate system. The groove shape and temperature distribution in the solid for both constant properties and variable properties, for different speeds, for various laser power levels and for different beam profiles are presented. The groove shapes for constant thermal properties are compared with a previous three-dimensional boundary element conduction model solution and a quasi-one-dimensional conduction model solution, in which the conduction losses were approximated using a simple integral method. The present model compares well with the three-dimensional boundary element model for all ranges of laser parameters, and, when thermal losses due to conduction are minor, the one-dimensional results are also in good agreement. Experimental results were obtained for material removal rates and groove shapes on silicon nitride, which were found to agree well with theoretical predictions for shallow grooves. For deeper grooves in silicon nitride beam guiding (i.e. multiple reflections within the groove) comes into play and the assumptions in the model are violated.
Validation of serum biomarkers derived from proteomic analysis for the early screening of preeclampsia.

Aim. To examine the potential value of previously identified biomarkers using proteomics in early screening for preeclampsia (PE). Methods. 24 blood samples from women who subsequently developed PE and 48 from uncomplicated pregnancies were obtained at 11–13 weeks and analysed after delivery. Cystatin-C, sVCAM-1, and Pappalysin-1 were quantified by ELISA. Maternal characteristics and medical history were recorded. Results. Median values of Cystatin-C, sVCAM-1, and Pappalysin-1 in the PE group as compared to controls were 909.1 gEq/mL versus 480.0 gEq/mL, , 832.0 gEq/mL versus 738.8 gEq/mL, , and 234.4 gEq/mL versus 74.9 gEq/mL, , respectively. Areas under the receiver-operating characteristic curves (AUC, standard error (SE)) for predicting PE were Cystatin-C: 0.90 (SE 0.04), VCAM-1: 0.66 (SE 0.074), and Pappalysin-1: 0.63 (SE 0.083). To discriminate between cases at risk for PE and normal controls, cut-off values of 546.8 gEq/mL for Cystatin-C, 1059.5 gEq/mL for sVCAM-1, and 220.8 gEq/mL for Pappalysin-1 were chosen, providing sensitivity of 91%, 41%, and 54% and specificity of 85%, 100%, and 95%, respectively. Conclusions. sVCAM-1 and Pappalysin-1 do not improve early screening for PE. Cystatin-C, however, seems to be associated with subsequent PE development, but larger studies are necessary to validate these findings.
Transferrin gene expression in maternal liver, fetal liver and placenta during pregnancy in the mouse.

Summary Two clones that are homologous to the mouse liver transferrin gene were isolated from a differential screen performed on a mouse cDNA library constructed from placenta. Using an insert derived from the larger of these clones as a template for the generation of random primed cDNA probes, northern blots were conducted against total RNA collected sequentially from placenta (7 days before birth to birth), maternal liver (7 days before birth to birth) and fetal liver (5 days before birth to birth). An approximately 2.3 kb message was detected in all three tissues which was upregulated in late gestation. Message was very abundant in both maternal and fetal liver, and present, but weak, in placenta. The clones were partially sequenced and both clones contain sequence that is identical to mouse liver transferrin. The data presented demonstrate an increase in mRNA transferrin in late gestation in maternal and fetal liver. Additionally, the placenta expresses a gene homologous to liver transferrin and it also is upregulated in late gestation.
Artificial neural networks as meta-models of combat processes: Applications to line-of-sight computations

Abstract Modeling high resolution combat is a computationally intensive activity that often requires compromise in the completeness or fidelity of the model to accommodate existing computer technology. This trade-off will always be necessary, but implicit modeling of some processes can reduce the computational load at run time so CPU cycles may be devoted to other areas of the model. Unfortunately some costly processes, such as intervisibility calculations, are even more expensive (in terms of storage) to model implicitly. This paper examines the potential of artificial neural networks to serve as efficient meta-models for line-of-sight determination.
Characterization of Metastable Oligomers as Subunits of Amelogenin Protein Nanospheres

Amelogenin protein accounts for more than 90% of the protein content during tooth enamel biomineralization and controls the organized growth of enamel apatite crystals. The protein self-assembles into nanospheres in vitro. We manipulated the interactions between monomers by altering pH, temperature and protein concentration to create isolated metastable oligomers. Recombinant amelogenin (rP172), and three different mutants containing only a single tryptophan (W161,W45,W25) were used. We observed stable but unstructured oligomers with an average hydrodynamic radius (RH) of 7.5 nm at pH 5.5. Fluorescence experiments with single-tryptophan amelogenins revealed that upon oligomerization, the C-terminus is exposed at the surface of the oligomers, while the N-terminal region is involved in self-assembly. Schematics of the monomeric, oligomeric and nanosphere forms of amelogenin are indicated at the relevant pH in the figure; A plot of wavelength emission maxima of amelogenin over a range of pH values between 3.4 and 9.4. The blue-shift in emission wavelength was most apparent at around pH 6. We propose that nanospheres form via oligomers. We predict that nanospheres will break up to form oligomers in mildly acidic environments in vivo and might be functional components during enamel maturation.View Large Image | View Hi-Res Image | Download PowerPoint Slide
Validation of the specificity of the modified agglutination test for toxoplasmosis in pigs

Serum samples from Toxoplasma gondii-negative pigs infected with protozoa, helminths and viruses, and from fetal pigs were examined for cross reacting antibodies to T. gondii by the use of the modified agglutination test (MAT). Nonspecific reactions with T. gondii antigen were not found in 1:10 dilutions of sera from eight pigs experimentally infected with Sarcocystis miescheriana, 11 pigs infected with Ascaris suum, three pigs infected with Trichuris suis, ten pigs infected with Trichinella spiralis, nine pigs infected with various porcine viruses, six gnotobiotic pigs, and 82 fetal pigs. Antibodies were also not found in 1:25 dilution of sera from 200 naturally aborted fetal pigs. Thus, evidence for cross reactivity to T. gondii with unrelated or related organisms using the MAT was not found.
Phase constitution and coercivity of Pr2Fe7B3 alloys produced by melt spinning

Abstract Melt spun ribbons of Pr 2 Fe 7 B 3 alloys develop coercivities up to 2.0 T upon annealing between 620 and 660° C. Mossbauer spectra and X-ray powder diagrams show that the annealed samples consist of two phases, Pr 2 Fe 14 B and PrFe 4 B 4 . The minor loop coercivity is strongly dependent on the magnetizing field.
Sensory Channel Threats to Cyber Physical Systems: A Wake-up Call

Cyber-Physical Systems (CPS) is a relatively novel computing paradigm where there is a tight integration of communications, computation, and the physical environment. An important component of the CPS devices is the sensors they use to interact with each other and the physical world around them. With CPS applications, engineers monitor the structural health of highways and bridges, farmers check the health of their crops, and ecologists observe wildlife in their natural habitat. Nonetheless, current security models consider protecting only networking components of the CPS devices utilizing traditional security mechanisms (e.g., an intrusion detection system for the data that traverse the network protocol stacks). The protection mechanisms are not sufficient to protect CPS devices from threats emanating from sensory channels. Using sensory channels (e.g., light, temperature, infrared), an adversary can successfully attack systems. Specifically, the adversary can (1) trigger existing malware, (2) transfer malware, or (3) combine malicious use of different sensory channels to increase the impact of the attack on CPS devices. In this work, we focus on these novel sensory channel threats to CPS devices and applications. We first note how sensory channel threats are an emerging area for the CPS world. Then, we analyze the performance various sensory channel threats. Moreover, using an iRobot Create as our CPS platform, we exploit simple vulnerable programs on iRobot through its infrared channel. Finally, we introduce the design of a novel sensory channel aware intrusion detection system as a protection mechanism against the sensory channel threats for CPS devices.
Electromechanical linear actuators for Fourier transform spectrometers: a concept for extended range, high-resolution, solid-state actuators

A piezoelectric effect device is reported that provides highly controllable, extended linear motion in an easily usable package. Recent advances in materials, materials processing, and piezoelectric mechanics have been synthesized to demonstrate an all-solid-state electromechanical actuator for Fourier transform spectrometer mirror position control. This actuator is inherently linear and is therefore a major improvement in efficiency, size, and mass over motors and lead screws, which require conversion from rotary to linear actuation. Velocity control of 1% has been demonstrated over a range of 0.5 cm at a velocity of 1 cm/s. Scaling to a range of 4 cm and a velocity of 4 cm/s is discussed and currently appears feasible.
Complete Genome Sequence of Hepatitis E Virus from Rabbits in the United States

Hepatitis E virus (HEV) is a single-strand positive-sense RNA virus in the family Hepeviridae. The disease caused by HEV, hepatitis E, is an important public health problem in developing countries of Asia and Africa and is also endemic in many industrialized countries, including the United States. HEV has been identified from several other animal species in addition to humans, including the pig, chicken, mongoose, deer, rabbit, ferret, bat, and fish. Here we report the complete genome sequence of the first strain of HEV from rabbits in the United States. Sequence and phylogenetic analyses revealed that the U.S. rabbit HEV is a distant member of the zoonotic genotype 3 HEV, thus raising a concern for potential zoonotic human infection. A unique 90-nucleotide insertion within the X domain of the ORF1 was identified in the rabbit HEV, and this insertion may play a role in the species tropism of HEV.
An integral equation approach to diffusion

Abstract A method of solution of transient diffusion, e.g. heat conduction, problems in homogeneous and isotropic media with internal sources and arbitrary (including nonlinear) boundary conditions and initial conditions is proposed. The method is based on the reduction of the problem to one only involving surface values of temperature and/or heat flux in the form of an integral equation through the introduction of fundamental solutions and the use of Green's theorem. The integral equation is solved numerically for a specific example.
Electrocution and the Tar Heel state: The advent and demise of a southern sanction

During the latter decade of the nineteenth century and early decades of the twentieth century, adoption of the electric chair spread rapidly from the North, down the eastern seaboard, and throughout the Deep South States. The method of execution was hailed as technologically advanced, and proved to be the most prevalent means of execution in the twentieth century. In 1909, North Carolina became the sixth state in the nation to adopt the new method, which would later stand as a cultural icon of southern punishment. In 1935, the state oddly abandoned the method, and shifted to lethal gas, a method that until that time had only been employed in a few western states. While North Carolina’s violent crime rates and yearly executions rivaled those of the Deep South during the 1920s and 1930s, the state’s political and social climate would directly lead to the demise of a cultural artifact that became synonymous with the institution of southern justice.
Cocaine modulation of the mammalian circadian clock: potential therapeutic targets

The circadian system plays an integral role in regulating physiological and behavioral responses to cocaine, which contribute to abuse and relapse. To date, however, little is known of the mechanism(s) underlying cocaine effects on biological timing, and in particular, how this drug may impact the regulation of the master circadian clock of the suprachiasmatic nucleus (SCN). This review summarizes our current research into the chronotypic actions of acute and chronic cocaine. In initial experiments, it was shown that acute systemic and in vitro cocaine blocks the nocturnal SCN photic phase-resetting response critical for circadian entrainment to the light-dark cycle (LD). Cocaine treatment at midday also advances circadian clock phase, showing that this drug possess non-photic circadian phase-resetting properties. Next, chronic (weeks-months) cocaine regimens were used to model human drug abuse patterns. Such long-term oral drug exposures caused dramatic alterations in intrinsic circadian period and entrainment to LD that persisted long after cocaine withdrawal, suggesting long-term (possibly permanent) circadian disruptive effects. Lastly, we found that the acute systemic cocaine effects described above are blocked using a serotonin receptor antagonist (metergoline) targeted to the SCN in vivo, as well as in vitro , suggesting involvement of a serotonergic mechanism. Consistent with this hypothesis, mutant mice with a cocaine-insensitive serotonin transporter exhibited little or no circadian response to cocaine. Collectively, these results indicate that cocaine-induced perturbations of clock timing could produce chronic psychological and physiological stress, contributing to increased cocaine use and dependence. Earmarking the serotonergic system in mediating these cocaine effects offers a potential chrono-pharmacological approach for the treatment of cocaine abuse and addiction.
Example-guided physically based modal sound synthesis

Linear modal synthesis methods have often been used to generate sounds for rigid bodies. One of the key challenges in widely adopting such techniques is the lack of automatic determination of satisfactory material parameters that recreate realistic audio quality of sounding materials. We introduce a novel method using prerecorded audio clips to estimate material parameters that capture the inherent quality of recorded sounding materials. Our method extracts perceptually salient features from audio examples. Based on psychoacoustic principles, we design a parameter estimation algorithm using an optimization framework and these salient features to guide the search of the best material parameters for modal synthesis. We also present a method that compensates for the differences between the real-world recording and sound synthesized using solely linear modal synthesis models to create the final synthesized audio. The resulting audio generated from this sound synthesis pipeline well preserves the same sense of material as a recorded audio example. Moreover, both the estimated material parameters and the residual compensation naturally transfer to virtual objects of different sizes and shapes, while the synthesized sounds vary accordingly. A perceptual study shows the results of this system compare well with real-world recordings in terms of material perception.
A simple illustration of turbulent flame ball growth

ABSTRACT A flame ball growing into a turbulent mixture exhibits a speed which is proportional to its size - this effect is a consequence of the distorted flame surface: the inner flame regions “push” the outer regions, the magnitude of this velocity depends upon the flame surface density distribution. A simple two-dimensional, zero-thickness flame model interacting with defined eddies illustrates how rapidly this flame distortion occurs after a spark ignition. This distributed volume source effect is also the functional form of Groffs modified entrainment model of flame propagation. A result of this size dependent growth is exponential growth of flame area which is an essential feature of spark-ignition internal combustion engines.
Bradykinin enhances invasion of malignant glioma into the brain parenchyma by inducing cells to undergo amoeboid migration

The molecular and cellular mechanisms governing cell motility and directed migration in response to the neuropeptide bradykinin are largely unknown. Here, we demonstrate that human glioma cells whose migration is guided by bradykinin generate bleb-like protrusions. We found that activation of the B2 receptor leads to a rise in free Ca(2+) from internal stores that activates actomyosin contraction and subsequent cytoplasmic flow into protrusions forming membrane blebs. Furthermore Ca(2+) activates Ca(2+)-dependent K(+) and Cl(-) channels, which participate in bleb regulation. Treatment of gliomas with bradykinin in situ increased glioma growth by increasing the speed of cell migration at the periphery of the tumour mass. To test if bleb formation is related to bradykinin-promoted glioma invasion we blocked glioma migration with blebbistatin, a blocker of myosin kinase II, which is necessary for proper bleb retraction. Our findings suggest a pivotal role of bradykinin during glioma invasion by stimulating amoeboid migration of glioma cells.
The computational geowiki: what, why, and how

Google Maps and its spin-offs are highly successful, but they have a major limitation: users see only pictures of geographic data. These data are inaccessible except by limited vendor-defined APIs, and associated user data are weakly linked to them. But some applications require access, specifically geowikis and computational geowikis. We present the design and implementation of a computational geowiki. We also show empirically that both geowiki and computational geowiki features are necessary for a representative domain, bicycling, because (a) cyclists have useful knowledge unavailable except from cyclists and (b) cyclist-oriented automatic route-finding is enhanced by user input. Finally, we derive design implications: for example, user contributions presented within a route description are useful, and wikis should support contribution of opinion as well as fact.
A Chaos-Based High Quality PN Sequence Generator

Chaos-based PN sequence generators are widely investigated recently. Concrete implementation of theses chaos-based generators usually have some problems because any processor or chips are computation precision restricted, which greatly effects the statistical properties of a chaotic PN sequence. This paper proposes a couple chaotic systems based stochastic bit quantification algorithm, which extends the period of the chaotic PN sequence and strengthens the anti neural network based adaptive parameter attack ability under precision restricted condition. The balance and correlation properties of the generated sequence are analyzed. The sequence is proved to be a binary Bernoulli sequence and the side lobes of odd/even auto and cross correlation are proved to obey normal distribution N(0, 1/N). Experimental results show that the algorithm has excellent statistical properties, and can be used to generate PN sequence with higher quality than conventional schemes.
A static and dynamic finite element analysis of the 1971 San Fernando, California, earthquake

Summary. A two-dimensional finite element model was developed for the source region of the San Fernando earthquake. Stochastic inversion of the surface displacement data of Alewine was carried out to obtain estimates of the displacements and stress drops along the actual fault surface in the finite element model. We calculate an average slip of 222 cm with a rms fit to the data of 8 cm. The average computed stress drop was 290 bar, with a maximum of 650 bar. Using these calculated stresses in a dynamic model of the earthquake, we compute theoretical accelerograms for the Pacoima Dam site. For frequencies less than 2 Hz, we found that the observed accelerograms were fitted best by a model with a propagating source having a rupture velocity of approximately 2.5 km s-'. These results suggest that the dynamic finite element method can be used to estimate strong earthquake ground motion from extended sources (earthquakes) in many different complex geologic structures.
A high-throughput system for boron microsublimation and isotope analysis by total evaporation thermal ionization mass spectrometry.

RATIONALE Research on the ocean carbon cycle is vitally important due to the projected impacts of atmospheric CO2 on global temperatures and climate change, but also on ocean chemistry. The direct influence of this CO2 rise on the seawater pH can be evaluated from the boron isotopic composition in biogenic carbonates; however, conscientious laboratory techniques and data treatment are vital in obtaining accurate and precise results. A rapid-throughput boron purification and Total Evaporation Thermal Ionization Mass Spectrometry method was developed for high accuracy and precision boron isotopic analysis for small (ng) sample sizes. METHODS An improved microsublimation method, in which up to 20 samples can be processed simultaneously under identical temperature conditions, was developed. Several tests have confirmed the viability of this technique. First, seawater and Porites coral samples were processed with H2O2 and the results compared with those obtained using microsublimation; second, the impact of various sublimation times was evaluated; and third, quantitative recovery was assessed using standard addition. RESULTS Microsublimation provides a valid method for the quantitative recovery and separation of boron from both major elements and organic matter under low-blank conditions. The close agreement of our results with published values validates the accuracy of the measurements. The isotopic ratio for SRM 951a boric acid isotopic standard was 4.0328 ± 0.0054 (2 STD, n = 25). The reproducibility of boron isotopic composition for standards including AE121, IAEA B-1 and an in-house coral standard UM-CP1 was ±0.68‰ (2 STD, n = 15), ±1.12‰ (2 STD, n = 24), and ±1.17‰ (2 STD, n = 14), respectively. The sample sizes were <1 ng for each measurement. CONCLUSIONS The developed method for preparing and measuring boron isotopic values in a variety of carbonate materials should facilitate the reconstruction of past ocean pH conditions with decadal-scale resolution. Copyright © 2013 John Wiley & Sons, Ltd.
An Easy to Use Tool for Augmenting multimedia Lectures with Accessible Self-assessment Exercises

eTEACH is an authoring tool for creating online streaming-video multi-media lectures viewed in a Web-browser. Using eTEACH to provide out-of-class lectures allows faculty to engage students in active learning and problem-solving activities in class; with measured benefits. We report on two significant enhancements to eTEACH that further define it as a learning tool. First, we have added a self-assessment quiz feature that focuses the student on the content and indicates the level of competence with the material that he/she is expected to attain after having viewed the presentation. By asking questions related to the presentation and providing answers to those questions as part of the presentation, the student is more actively engaged. Quizzes are constructed using a Microsoft Word template and MathType plug-in. Second, we have a strong commitment to supporting students with disabilities, including blind students. The MathType plug-in produces mathematical formulas in MathML which the authoring tool uses to produce content that is easily navigated by screen-reading software
Computer controlled multielectrode impedance measurement system

The four electrode methodology for measuring electrical resistivity at low radiofrequency is a well established technique and has been documented extensively in the literature. Current is passed between the outer two electrodes of a linear four electrode array and the induced voltage between the two inner electrodes is measured. The circuitry that is associated with these measurements is generally easy to construct. In practice, however, real interest lies in making anisotropic resistive measurements of a medium. Furthermore, many applications require that measurements be made continuously to observe dielectric changes over a finite period of time. This paper presents a practical approach for making continuous anisotropic four-electrode measurements.
Repression of glycoprotein hormone alpha-subunit gene expression and secretion by activin in alpha T3-1 cells.

The alpha T3-1 cell line, a GnRH-responsive gonadotroph cell line developed by targeted oncogenesis in transgenic mice, was used to study regulation of the glycoprotein hormone alpha-subunit by activin. Transient transfection assays established that activin suppressed transcription of both the human and mouse alpha-subunit genes. Initial studies demonstrated that activin decreased transcription of -846 and -180 human alpha-subunit-luciferase constructs by about 30%, but that inhibin and follistatin were without effect. Subsequent studies to localize sequences mediating responses to activin were carried out using a series of 5'-deletions (-507 to -133) of the mouse alpha-subunit promoter fused to luciferase. The luciferase activity of the -507-base pair construct was decreased by 60-70% in the presence of activin, and follistatin prevented this decrease. There were significant stepwise losses of activin responsiveness when sequences between -507 and -424, -424, and -288, and -288 and -205 base pairs were e...
Entrepreneurship and Earnings among Young Adults from Disadvantaged Families

Academicians and policymakers have argued that entrepreneurship provides a route out of poverty and an alternative to unemployment or discrimination in the labor market. Existing research, however, provides little evidence from longitudinal data on the relationship between business ownership and economic advancement for disadvantaged groups. I use data from the National Longitudinal Survey of Youth (NLSY) to examine the earnings of young business owners from disadvantaged families and make comparisons to young wage/salary workers from disadvantaged families. For young men from disadvantaged families, I find some evidence that self-employed business owners earn more than wage/salary workers. In contrast, I find that for young women from disadvantaged families business owners earn less than wage/salary workers. The results from these earnings comparisons are somewhat sensitive to the use of different measures of income and econometric models.
Bilayer piezoelectric/electrostrictive (P/E) dome unimorph

We present a new type of actuator named bilayer piezoelectric/electrostrictive dome unimorph (BIPEDU), fabricated by attaching a piezoelectric-electrostrictive monolithic bilayer composites (PE-MBLC) to a metal plate. Various ratios of piezoelectric/electrostrictive (P/E) volume percent were used to form PE-MBLC. It was found that d33 eff and Keff in PE-MBLC follow the series 2-2 composite mixing rule. However, the measured results were slightly lower than those of the calculated values because of a large difference in dielectric displacement between piezoelectric and electrostrictive layers and because the electrostrictor acts as the resistor that impedes the domain switching in piezoelectric layer during poling. In addition, we have investigated the field-induced displacement in PE-MBLC and BIPEDU actuators. In comparison, the displacement of BIPEDU actuators was much higher than that of PE-MBLC actuators. This was attributed to the good quality of bonding between ceramic and metal, which contributed to the proper stress/force transfer, as well as the metal sheet, which acted as a flextentional structure for PE-MBLC to generate more axial displacement in BIPEDU actuators. The load dependence of displacement in BIPEDU was obtained. In addition, the BIPEDU showed high reliability during the displacement cyclic testing.
Null-Space Grasp Control: Theory and Experiments

A key problem in robot grasping is that of positioning the manipulator contacts so that an object can be grasped. In unstructured environments, contact positions are typically planned based on range or visual measurements that are used to reconstruct object geometry. However, because it is difficult to measure the complete object geometry precisely in common grasp scenarios, it is useful to employ additional techniques to adjust or refine the grasp using local information only. In particular, grasp control techniques can be used to improve a grasp by adjusting the contact configuration after making initial contact with an object by using measurements of local object geometry at the contacts. This paper proposes three variations on null-space grasp control: an approach that combines multiple grasp objectives to improve a grasp. Two of these variations are theoretically demonstrated to converge to force-closure configurations for arbitrary convex objects when grasping with two contacts. All variations are found to converge in simulation. Robot-grasping experiments are reported that show the approach to be useful in practice.
New classes of reconstruction methods in reflection mode diffraction tomography

Reflection mode diffraction tomography (DT) is an inversion scheme used to reconstruct the spatially variant refractive index distribution of a scattering object. We propose a linear strategy that makes use of the statistically complementary information inherent in the reflected scattered data to achieve a bias-free reduction of the image variance in two dimensional (2D) reflection mode DT. We derive infinite classes of estimation methods that can estimate the 2D Radon transform of the (band-pass filtered) scattering object function from the reflected scattered data. When the insonifying source is broadband we demonstrate that incorporation of the statistically complementary information generated by each frequency in the incident spectrum can further reduce the variance of the images reconstructed using different estimation methods.