cssi/SciSciGPT-SciSciNet huggingface dataset:
The Neutron Spherical Optical Model Absorption

Abstract The energy-dependent behavior of the absorption term of the spherical neutron optical potential for doubly magic 208Pb and neighboring 209Bi is examined. These considerations suggest a model with an intuitively attractive energy dependence of the imaginary potential that provides a good description of the observed neutron cross-sections and that is qualitatively consistent with theoretical concepts. It is an alternative to arbitrary assumptions involved in many conventional optical-model interpretations reported in the literature.
Quantum cryptography at 830nm in standard telecommunications fiber

Quantum cryptography systems can operate over relatively long distances in standard telecommunications fiber by taking advantage of the low transmission losses in these fibers at 1.3 or 1.5 microns. Although there has been much progress toward the development of highly efficient and low-noise detectors for these wavelengths, silicon avalanche photodiodes currently offer superior single photon counting performance, but only at visible and near IR wavelengths where the fiber transmission is poor. For ranges typical of local area networks, it is possible that a quantum key distribution (QKD) system operating below 850nm could be optimal, even though standard telecommunications fiber supports multiple optical modes at these wavelengths. We have recently developed an optical mode filter that allows efficient higher order mode rejection from standard telecommunications fiber near 830nm. We have used this type of filter to launch and recover QKD signals from a polarization-based system implementing the BB84 quantum cryptography protocol. Here we present results from testing and operation in installed fiber links ranging up to 3km. These results demonstrate that the filters can attenuate the higher order modes over 35dB while having a minimal (<1dB) impact on the fundamental mode carrying the QKD signal.
Effects of parasitism by the lung fluke, Haematoloechus medioplexus, on lung fatty acid and sterol composition in the bullfrog, Rana catesbiana.

Abstract Gas-liquid chromatography was employed to determine cholesterol and total lipid fatty acid levels in lung tissue and blood from bullfrogs harboring natural infections of the lung fluke, Haematoloechus medioplexus . As compared with uninfected animals, infected hosts exhibited (1) negligible alterations in blood sterols and fatty acids, (2) consistently larger lungs, (3) a 40 per cent decrease in lung lipids, (4) a 50 per cent increase in lung cholesterol, and (5) little difference in mean values, but a higher variability in percentages of lung fatty acids. The parasite's fatty acid profile was more similar to that of host lung tissue than blood and exhibited a relatively high degree of unsaturation; cholesterol was the major sterol.
The structure of trimethylenemethane-ML2 complexes and Their relationship to cycloaddition reactions

Abstract An electronic reason is offered why d 10 and d 8 trimethylenemethane-ML 2 complexes should be η 3 rather than η 4 . This was checked by molecular orbital calculations of the extended Huckel type. Both sets of complexes can be regarded as zwitterionic with the uncomplexed methylene group for the d 10 compounds anionic and cationic for the d 8 analogs. In both cases, interconversion between the three equivalent η 3 geometries does not proceed via an η 4 structure. We find that η 2 geometries serve as way-points in this fluxional rearrangement. Implications are also drawn to the mode of cycloaddition of methylenecyclopropanes to electron deficient olefins by d 10 ML n catalysis and ring-opening of the methylenecyclopropanes.
Co-stimulation in T cell responses

Antigen-specific T cell responses have primarily been considered in terms of activation signals delivered through the TCR and the co-stimulatory molecule CD28. In the past few years, studies have demonstrated the critical importance of inhibitory signals for regulating lymphocyte activation. CD28 and its homologue cytotoxic T lymphocyte antigen-4 (CTLA-4) share the same counter-receptors on antigen-presenting cells, but recent experiments have shown that CD28 and CTLA-4 have opposite effects on T cell activation. The mechanisms responsible for integrating these activation and inhibitory signals at the cellular and molecular levels are just beginning to be elucidated.
Coulometric Study of Ethanol Adsorption at a Polycrystalline Platinum Electrode

Abstract For the first time, use of a novel pre-conditioning sequence and measurements of hydrogen blockage during fast cathodic scans has enabled the determination of rates of accumulation of ethanolic species on the surface of a platinum electrode under well-controlled conditions of surface cleanliness/activity and mass transport. For dilute solutions of ethanol in 1 N perchloric acid (HClO 4 ), oxidative adsorption rates maximize at 0.3 V, drop off at more cathodic potentials due to competition with adsorbed hydrogen and drop off at more anodic potentials due to oxidative processes that produce products released to the electrolyte. The time and concentration dependence of adsorption follows relationships that are common for adsorption on a heterogeneous surface. Some evidence are presented supporting a mechanism for production of soluble products that does not involve the adsorbed species that are detected through the measurement of blockage of hydrogen adsorption sites.
The cognitive factor in the extinction of a conditioned GSR

This study investigated the effect of cognition on the extinction of a conditioned GSR. The difference between extinction rates indicated that the Ss who could form the cognition that the UCS would no longer be presented extinguished more rapidly than Ss who could not. The data were interpreted as support for the role of awareness in the extinction of a classically conditioned response.
Human health risk from arsenical pesticide contaminated soils: A long-term greenhouse study

Arsenic (As) bioaccessibility is an important factor in estimating human health risk. Bioaccessibility of As in soils is primarily dependent on As adsorption, which varies with residence time. This study evaluated the effect of soil aging on potential lifetime cancer risk associated with chronic exposure to As contaminated soils. Four soils, chosen based on their differences in As reactivity, were amended with two arsenical pesticides--sodium arsenate, and dimethylarsinic acid (DMA) at two rates (675 and 1500 mg kg(-1)). Rice was used as the test crop. Soil was sampled immediately after spiking, after 6 months, 1 year, and 3 years. Bioaccessible and total soil As concentrations were used to calculate lifetime excess cancer risk (ECR), which decreased significantly with soil-pesticide equilibration time. Immokalee soil, with the least As adsorption capacity, showed the highest decrease in ECR after 6 months resulting in values lower than the USEPA's cancer risk range of 1 × 10(-4) to 1 × 10(-6). For all other soils, the ECR was much higher than the target range even after 3 years. In the absence of significant changes in As bioaccessibility with time, the total soil As concentration more directly influenced the changes in ECR values with soil aging.
A comparison of AMIP II model cloud layer properties with ISCCP D2 estimates

The cloud amounts and liquid and ice water paths as a function of height in five Atmospheric Model Intercomparison Project (AMIP) II models have been compared to International Satellite Cloud Climatology Project (ISCCP) d2 observations. The model layer data have been transformed to the ISCCP low, mid and height cloud amount and vertically integrated water values. In addition a simple radiative transfer model has been used to transform both model output and ISCCP cloud amount and water contents into top of atmosphere albedos for the low, mid and high cloud fractions. Overall, most models represent moderately well the spatial, seasonal and interannual variability of total cloud albedo, which is largely a function of the total cloud amount. The models also tend to predict moderately well the spatial, seasonal, and interannual variability of cloud fraction, but fail to display the observed spatial, and especially, seasonal and interannual variability in cloud water path. In particular nearly all models have mid and low cloud water path variabilities, which are much larger than those observed in the ISCCP observations. This increased cloud water path variability seems to compensate partially for smaller underestimates of cloud fraction variability in most models. Furthermore, variations in cloud amount and cloud water path are much more often negatively correlated in models than in the observations. A simple estimate of the influence of cloud overlap suggests that monthly mean model cloud layers are less stacked in the vertical in models than in an observational estimate based upon a combination of satellite and ground-based observations.
Detached-Eddy Simulation of Rotating Stall Inception for a Full-Annulus Transonic Rotor

Full-annulus detached-eddy simulation (DES) is conducted in this paper to investigate stall inception for the axial transonic rotor, NASA rotor 67. A low-diffusion E-CUSP scheme with a third-orderMUSCL reconstruction is used to discretize the inviscid fluxes, and second-order central differencing is used for the viscous terms. An implicit line Gauss–Seidel iteration with dual time-stepping method and second-order temporal accuracy is employed for time integration of the spatially filtered unsteady Navier–Stokes equations in a rotating frame. It is observed that the rotating stall is initiated by the local spike flow disturbance, which quickly induces the rotor to stall roughly over two rotor revolutions. The stall cell covering more than six blade tip passages propagates at 48% of rotor speed in the counter-rotor rotation direction. The process of rotating stall is captured by the full-annulus DES, which indicates that the blockage created by the low-energy vortical flow structure pushes the tip leakage flow to the adjacent blade behind the detached sonic boundary. The unsteady Reynolds-averaged Navier–Stokes (URANS) simulation is also performed for comparison. DES predicts the stall inception roughly one rotor revolution earlier than the URANS model. Overall, DES predicts the stall inception more realistically.
Phosphotyrosine signaling and the single cell:metazoan boundary

Systematists classify together three groups of organisms that are referred to as “slime molds,” the Myxogastria, Dictyostelia, and Protostelia (3). The Protostelids are the least studied. The Myxogastria include the well studied Physarum polycephalum, a prototypical single-celled ameba that can also form a large multinucleate plasmodium (4). Dictyostelium discoideum, described in 1935 by K. B. Raper (5) and studied intensively for almost 50 years by developmental biologists (6, 7), is the classic Dictyostelid. All three groups share the important characteristic features of both growing as single cells and differentiating into multicellular, stalked structures called fruiting bodies that bear haploid spores in a spore cup.
Momentum fluctuations of heavy quarks in the gauge-string duality

Abstract Using the gauge-string duality, I compute two-point functions of the force acting on an external quark moving through a finite temperature bath of N = 4 super-Yang–Mills theory. I comment on the possible relevance of the string theory calculations to heavy quarks propagating through a quark–gluon plasma.
Microphotonic systems utilizing SU-8

SU-8 is a negative-tone photoresist that can serve as a complete optical bench for micro-photonic systems. Functional optical devices and passive alignment structures can all be formed in the same material system with common processing steps. Many interrelated process parameters control the final geometry of structures formed in SU-8, but all can be accurately simulated and predicted by computer modeling. In this work, a comprehensive model of the lithography process was developed and combined with rigorous electromagnetic simulation. It was applied to predict sidewall slope of a tall structures as well as the geometry and transmission spectra of a three-dimensional photonic crystal. The model is seen as an enabling step toward realizing optimized micro-photonic systems in SU-8.
Informality and Regulations: What Drives the Growth of Firms?

This paper relies on rich firm-level data on transition economies to examine the role of informality as an important channel through which regulatory and other policy constraints affect firm growth. We find that firms reduce their formal operations with greater tax and regulatory burdens, but increase them with better enforcement quality. In terms of firm growth, we find a differential impact of regulatory burden and enforcement quality on formal and informal firm growth. In particular, we find that growth in formal firms is negatively affected by both tax and financing constraints, whereas these constraints are insignificant for growth in informal firms. Moreover, formal firm growth improves with better enforcement, while informal firm growth is constrained by organized crime, pointing to informal firms' inability to take full advantage of the legal and judicial systems. Finally, we find that an interaction term between a countrywide measure of the rule of law and formality is positive, suggesting that better rule of law improves formal firm growth.
A theory of the functional organization of the neostriatum and the neostriatal control of voluntary movement

Abstract A theory of the intrinsic, functional organization of the neostriatum and the neostriatal control of voluntary movement is presented. The cell types of neostriatum are described in accordance with the classification scheme of Pasik, Pasik and DiFiglia (ref. 204) and their suspected neurotransmitters are identified. The functional relations between the afferent projections to neostriatum and the intrinsic elements of neostriatum are described. A division of the neostriatal efferents into two functional cell systems is conceived, in which one efferent system, the Spiny I cell matrix, is thought to be represented by a lateral inhibitory network comprised of the common Spiny I neurons which inhibit their targets, while another is termed the Spiny II cell cluster and consists of the far less numerous excitatory efferents of neostriatum (the Spiny II cells) and is represented by clusters of neurons, the members of each cluster consisting of one excitatory efferent neuron and three interneurons. The implications of this view for neostriatal input-output relations are discussed, and the theory is developed by reference to a variety of converging lines of empirical evidence, and is used to interpret the effects of various pharmacologic strategies which have been employed to achieve symptom management in disorders of voluntary movement. In the course of this review, there emerges an integrative theory of the principles governing the neostriatal control of voluntary movement.
Lys- and glu-plasminogen potentiate the inhibitory effect of recombinant tissue plasminogen activator on human platelet aggregation.

To examine the basis of enhanced thrombolytic effect of tissue-type plasminogen activator (t-PA) in the presence of lys- or glu-plasminogen, studies were performed with human platelet-rich plasma (PRP) and washed platelets (WP). t-PA inhibited platelet aggregation in PRP and this effect was potentiated by lys-plasminogen as well as glu-plasminogen. t-PA inhibited WP aggregation only in the presence of lys- or glu-plasminogen. The potentiation of the effects of t-PA was greater (P<0.05) with lys-plasminogen than with glu-plasminogen. t-PA alone also decreased 14C-serotonin release from WP, and lys- as well as glu-plasminogen reversed this effect of low concentrations of t-PA in WP. Aggregation of WP was also inhibited by plasmin, a proteolytic product of plasminogen. Low, but not high concentrations, of plasmin increased the release of 14C-serotonin. Anti-aggregatory effects of plasmin and lys-plasminogen plus t-PA on platelets were attenuated by preincubation of PRP or WP suspension with aprotinin. These observations suggest enhanced inhibitory effect of t-PA on platelet function in the presence of lys-plasminogen as potential basis of salutary interaction in models of arterial thrombosis.
Controlling polymer formation during polysilicon etching in a magnetically enhanced reactive ion etcher

Studies were conducted in a magnetically enhanced reactive ion etcher to understand the material and process related issues affecting polymer formation during a polysilicon etch. Samples consist of POCl3 doped and undoped polysilicon which are patterned with two different types of photoresist. Processing is done using a Cl2/HBr chemistry with some of the experiments having oxygen added during the over etch step of the process. Scanning electron microscope results indicate two very distinct structures exist on the various samples. One that exhibits a more uniform polymer and the other that leaves an `ear' shaped polymer formation. These various structures also are analyzed using x-ray photoelectron spectroscopy. This analysis indicates the polymers to be a combination of silicon, oxygen, and carbon. Based on this study it is apparent that the type of material, photoresist, and process variables significantly influence the polymer formation during the etching of undoped and doped polysilicon with an HBr/Cl2 chemistry.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Democratic Pedagogy and the Discourse of Containment

This article points to the application of a discourse of containment in pedagogical practice. Growing out of a containment culture that has its beginnings in Cold War domestic strategies, the discourse of containment limits democratic possibilities in our classrooms, producing and legitimating a culture that governs what can be said and who can speak. Drawing on the mythologized version of the Rosa Parks story and the current agenda of conservative cultural managers and news media to contain the story around September 11,1 analyze the stakes in the political struggle over the control of the production of meaning in our classrooms.
Timing Uncertainty For Receivers In Optical Clock Distribution For VLSI

Optical interconnection techniques have been suggested to reduce signal skew for clock distribution for silicon VLSI chips. One optical approach for clock distribution is to holographically map an optical signal from an off-chip source to several photoreceivers within small functional cells on a chip surface. Within each functional cell, the clock is distributed via short surface wires with negligible delays. In such a system, the primary source of timing uncertainty is due to fabrication-related variation of transistor parameters between identically drawn receivers on a chip. We present here an overview of the distribution system and two receiver designs. A test chip has been designed and fabricated, and laboratory measurements of transimpedance receiver parameters are presented. Analysis and simulation studies show that a phase-locked loop receiver based on a voltage-controlled ring oscillator can offer two orders of mag-nitude improvement in receiver skew over a simple transimpedance amplifier design, allowing a total synchronization uncertainty on the order of 55 ps while operating at 100 to 200 MHz and requiring much less layout area than the transimpedance amplifier.
Simulation of locked-cycle grinding tests using multicomponent feeds

Locked-cycle grinding tests using multicomponent feeds provide valuable insight into the dynamics of industrial closed-grinding circuits processing heterogeneous ores. These tests, however, are very laborious and time consuming. We present one general and two simplified mathematical algorithms for cycle-wise simulation of locked-cycle tests grinding mixture feeds. The algorithms have been tested against experimental data on locked-cycle grinding of calcite-quartz feed. Whereas single-component feeds require 3 to 6 cycles to attain steady state, mixture feeds need anywhere up to 35 cycles. The higher the hard mineral content of the feed, the greater is the change in the circulating load from one cycle to the next. The steady state recycle values vary steeply and almost linearly with the composition. These results imply that the closed-circuit grinding of heterogeneous ores is inherently less stable than those processing nominally pure minerals. The predominance of a soft matrix in the ores should enhance the stability of the circuit somewhat. Random and unintended variations in ore characteristics and feed rates, even relatively minor ones, make it virtually impossible to assure a stable performance for any length of time.
A Hybrid Ab Initio/Free Electron Computational Model for Conjugated Dye Molecules: Simple Cyanines and Oxonols

Justifications developed for the application the free electron model to the π-orbitals of conjugated molecules suggest that the optical properties of these molecules would be well described by a one-dimensional free electron model with a potential chosen to reproduce the energy level spacing of the ground state occupied π-orbitals. Such a hybrid ab initio/free electron modeling approach, where the free electron potential parameters are optimized on a molecule-by-molecule basis, is developed, and applied to a series of simple cyanine and oxonol dyes. The ensuing predictions for λmax, oscillator strengths, and redox properties compare well to available experimental information. Two important strengths of this approach are that no explicit calculations of the excited electronic state are required, and that the ab initio determination of the occupied π-orbital level spacing considers all the electrons (π and σ) of the entire molecule in a specified geometry, environment, etc. This second characteristic gives the ability to efficiently model modifications of the optical properties of conjugated molecules resulting from chemical and/or physical modifications occuring within and remote to the conjugated region of the molecule. © 2000 John Wiley & Sons, Inc. J Comput Chem 21: 943–953, 2000
Regional specificity of age effects on the neural correlates of episodic retrieval.

We investigated age-related differences in episodic retrieval using a source memory procedure. Age-related differences in retrieval-related activity were analyzed in conditions where source recollection performance was statistically equivalent in young and older subjects. Analyses of BOLD activity revealed a network of regions where recollection effects were equivalent in magnitude in the two age groups. There were no regions where these effects were of greater magnitude in young than in older subjects. In some regions, however, there was a crossover interaction, such that retrieval-related effects reversed in direction between the two age groups. Further analyses of these interactions revealed a dissociation between a posterior hippocampal region where recollection-related activity was confined to the older group, and right fusiform and occipital regions where, in the young group only, activity elicited by studied items was of lower magnitude than activity to new items. We interpret the first of these age-related effects as an example of ‘over-recruitment’ in response to decline in neural efficiency, and discuss whether the second effect indexes an age-related decline in repetition priming.
FEYNMAN RULES AND QUANTUM ELECTRODYNAMICS AT INFINITE MOMENTUM.

We have studied the Feynman rules in terms of the new variables $s={p}^{0}\ensuremath{-}{p}^{3}$, $\ensuremath{\eta}={p}^{0}+{p}^{3}$, $\mathrm{q}=({p}^{1}, {p}^{2})$ in the ${\ensuremath{\varphi}}^{3}$ model and in quantum electrodynamics. The connection between the new variables and the dynamics at infinite momentum is established. In the ${\ensuremath{\varphi}}^{3}$ model, one easily deduces Weinberg's rules at infinite momentum upon integrating over the $s$ variables in the propagators without taking the ${p}^{3}\ensuremath{\rightarrow}\ensuremath{\infty}$ limit. The new Feynman rules lead to much simpler calculation of the second-order self-energies and the magnetic moment in quantum electrodynamics. It is still unclear if there is advantage in computing higher-order terms in quantum electrodynamics with the new rules.
TCP-Jersey for wireless IP communications

Improving the performance of the transmission control protocol (TCP) in wireless Internet protocol (IP) communications has been an active research area. The performance degradation of TCP in wireless and wired-wireless hybrid networks is mainly due to its lack of the ability to differentiate the packet losses caused by network congestions from the losses caused by wireless link errors. In this paper, we propose a new TCP scheme, called TCP-Jersey, which is capable of distinguishing the wireless packet losses from the congestion packet losses, and reacting accordingly. TCP-Jersey consists of two key components, the available bandwidth estimation (ABE) algorithm and the congestion warning (CW) router configuration. ABE is a TCP sender side addition that continuously estimates the bandwidth available to the connection and guides the sender to adjust its transmission rate when the network becomes congested. CW is a configuration of network routers such that routers alert end stations by marking all packets when there is a sign of an incipient congestion. The marking of packets by the CW configured routers helps the sender of the TCP connection to effectively differentiate packet losses caused by network congestion from those caused by wireless link errors. This paper describes the design of TCP-Jersey, and presents results from experiments using the NS-2 network simulator. Results from simulations show that in a congestion free network with 1% of random wireless packet loss rate, TCP-Jersey achieves 17% and 85% improvements in goodput over TCP-Westwood and TCP-Reno, respectively; in a congested network where TCP flow competes with VoIP flows, with 1% of random wireless packet loss rate, TCP-Jersey achieves 9% and 76% improvements in goodput over TCP-Westwood and TCP-Reno, respectively. Our experiments of multiple TCP flows show that TCP-Jersey maintains the fair and friendly behavior with respect to other TCP flows.
Thank you to a class act.

In 2006, Dr. Jarvis described Infection Control and Hospital Epidemiology (ICHE) as a journal transitioning through adolescence with the assistance of a new publisher, the University of Chicago Press (UCP). Major issues of that day included a large backlog that occurred as a consequence of rising submissions and stable rejection rates. Since that time, the journal has continued to thrive; we anticipate that in 2014 the number of submissions will have almost doubled over the past 8 years. Five supplements have been published during this time frame, and three of these issues were released just in the last 5 months. Founded as one of the main divisions of the University of Chicago, UCP has clearly met its overarching academic mission to “disseminate scholarship of the highest standard.” ICHE is an outstanding example of that commitment. No matter how busy ICHE has become, UCP has never thought twice about increasing resources and staff to get the job done. We thank the current and former directors of the UCP Journals Division, Michael Magoulias and Everett Conner, and the publisher, Gordon Rudy, for their unwavering support of ICHE. The managing editor is typically the public face of ICHE and the first person that authors, readers, editors, and society members encounter when seeking advice about matters pertaining to the journal. Rob Blixt and his predecessors, Gordon Rudy and Anne Marie McCormack, have served as outstanding resources for publishing advice and customer service while simultaneously maintaining the flow of papers from the editorial office to production, a major feat in itself. Finally, there are many people who have worked in relative anonymity to make sure that accepted papers are meticulously and accurately copy edited and typeset. There have been very, very few errata on UCP’s watch. Over the past few years, the economic downturn has greatly affected academic and for-profit publishers alike, resulting in increasing competition for fewer subscribers (libraries, healthcare facilities, and individuals) and declining advertising dollars. In 2013, the Society for Healthcare Epidemiology of America board of directors elected to hire a new publisher, Cambridge University Press, effective January 1, 2015. During this time of transition, UCP has worked very closely with Cambridge staff to assure that the journal’s processes, submissions, and archived materials are transferred seamlessly. I am confident that you will not notice any changes in the functioning or quality of ICHE in the days to come. In their lyrics, Ebb and Kander bemoaned the lack of values, manners, and mores among the citizens of the Windy City during the early twentieth century. In fact, be assured that “class” is alive and well and residing within the walls of UCP.
The Convergence Years.

The emergence of the Internet, social media, and digital technologies in the twenty-first century accelerated an evolution in journalism and communication that fit under the broad term of convergen...
The Influence of Feedback Valence in Associative Learning

The neural systems engaged by intrinsic positive or negative feedback were defined in an associative learning task. Through trial and error, participants learned the arbitrary assignments of a set of stimuli to one of two response categories. Informative feedback was provided on less than 25% of the trials. During positive feedback blocks, half of the trials were eligible for informative feedback; of these, informative feedback was only provided when the response was correct. A similar procedure was used on negative feedback blocks, but here informative feedback was only provided when the response was incorrect. In this manner, we sought to identify regions that were differentially responsive to positive and negative feedback as well as areas that were responsive to both types of informative feedback. Several regions of interest, including the bilateral nucleus accumbens, caudate nucleus, anterior insula, right cerebellar lobule VI, and left putamen, were sensitive to informative feedback regardless of valence. In contrast, several regions were more selective to positive feedback compared to negative feedback. These included the insula, amygdala, putamen, and supplementary motor area. No regions were more strongly activated by negative feedback compared to positive feedback. These results indicate that the neural areas supporting associative learning vary as a function of how that information is learned. In addition, areas linked to intrinsic reinforcement showed considerable overlap with those identified in studies using extrinsic reinforcers.
Genetic background affects expression of t haplotype in mouse sperm.

Two aspects of sperm phenotype were examined for t w 32 /+ males of the inbred strains C3H and C57BL/6 (B6). Sperm from fertile C3H- t w 32 /+ males very rarely achieved fertilization in vitro, while sperm from congenie C3H-+/+ males had no such difficulties. The presence of t w 32 had no effect on ability of B6 sperm to undergo fertilization in vitro. In fertile hybrid males produced from crosses of B6 and C3H strains, t w 32 significantly reduced, but did not inhibit completely, the sperms' ability to fertilize in vitro. The presence of t w 32 decreased by a factor of two the frequency of abnormal sperm heads in males of the B6 strain, but doubled the frequency in the C3H strain. Hybrid males resembled the C3H strain in this respect. The presence of T or T 2 J had no effect on the level of sperm abnormalities in any strain. These results emphasize the importance of genetic background in expression of t haplotypes in sperm, and suggest that t w 32 can influence a range of sperm characteristics, by interacting with products of other loci.
The Supreme Court as a Cheerleader in Politico-Moral Disputes

This address explores the Supreme Court's involvement in the nation's politico-moral disputes. The Court sometimes injects itself into these disputes and through dicta and other inspirational activities becomes a cheerleader for one side. I consider the effectiveness of the Court's cheerleading in inspiring change in national policy following Roe v. Wade (1973) and Brown v. Board (1954), finding that judicial cheerleading was much more effective for achieving a consensus about desegregation than for achieving one about abortion rights. I conclude by arguing that the Court's cheerleading: (1) has the capacity to bring politico-moral issues to the front burner, (2) is more effective in supporting change rather than in defending the status quo, (3) does not frighten or shame the losing side into abandoning its cause, often having the opposite effect, and (4) must persuade the uncommitted within a decade if its cause is to be successful.
AP-1 transcription factor complex is a target of signals from both WNT-7a and N-cadherin-dependent cell-cell adhesion complex during the regulation of limb mesenchymal chondrogenesis

Wnt signaling has been implicated in the regulation of limb mesenchymal chondrogenesis. In this study, we have analyzed the molecular mechanism of Wnt-7a inhibition of chondrogenic differentiation by examining the involvement of mitogen-activated protein kinase (MAPK) pathways, i.e., Erk and p38. The combination of Wnt-7a misexpression and Erk inhibition partially recovers Wnt-7a inhibition of chondrogenic differentiation, whereas the combination of Wnt-7a misexpression and p38 inhibition acts in a synergistic chondro-inhibitory fashion. Although Wnt-7a misexpression has no direct effect on Erk signaling, it increases the activity of one of the ultimate targets of the MAPK pathway, c-jun, a major component of the activator protein-1 (AP-1) transcription factor complex. In addition, Wnt-7a misexpression enhances the activity of an AP-1 promoter-luciferase reporter construct by approximately 2.3-fold in vitro. Interestingly, misexpression of wild-type N-cadherin in these micromass cultures suppresses the activity of the same AP-1 promoter by approximately 40%, whereas misexpression of an extracellular 390-amino-acid N-terminal deletion mutant of N-cadherin has a stimulatory effect on the AP-1 promoter activity by approximately 2.6-fold. Thus, our results suggest that at least a part of the chondro-inhibitory effect of Wnt-7a misexpression may involve AP-1 transcription factor stimulation. Furthermore, a very tightly regulated level of AP-1 activity is necessary for the process of limb mesenchymal chondrogenesis, and signals from Wnt-ligands (e.g., Wnt-7a), cell adhesion molecules (e.g., N-cadherin), and MAPK pathways (e.g., Erk and p38) are interactively involved in this regulation.
Yersinia murine toxin is not required for early-phase transmission of Yersinia pestis by Oropsylla montana (Siphonaptera: Ceratophyllidae) or Xenopsylla cheopis (Siphonaptera: Pulicidae).

Plague, caused by Yersinia pestis, is characterized by quiescent periods punctuated by rapidly spreading epizootics. The classical ‘blocked flea’ paradigm, by which a blockage forms in the flea’s proventriculus on average 1–2 weeks post-infection (p.i.), forces starving fleas to take multiple blood meals, thus increasing opportunities for transmission. Recently, the importance of early-phase transmission (EPT), which occurs prior to blockage formation, has been emphasized during epizootics. Whilst the physiological and molecular mechanisms of blocked flea transmission are well characterized, the pathogen–vector interactions have not been elucidated for EPT. Within the blocked flea model, Yersinia murine toxin (Ymt) has been shown to be important for facilitating colonization of the midgut within the flea. One proposed mechanism of EPT is the regurgitation of infectious material from the flea midgut during feeding. Such a mechanism would require bacteria to colonize and survive for at least brief periods in the midgut, a process that is mediated by Ymt. Two key bridging vectors of Y. pestis to humans, Oropsylla montana (Siphonaptera: Ceratophyllidae) or Xenopsylla cheopis (Siphonaptera: Pulicidae), were used in our study to test this hypothesis. Fleas were infected with a mutant strain of Y. pestis containing a non-functional ymt that was shown previously to be incapable of colonizing the midgut and were then allowed to feed on SKH-1 mice 3 days p.i. Our results show that Ymt was not required for EPT by either flea species.
Evidence for a Dual Source of Relaxin in the Pregnant Rat: Immunolocalization in the Corpora Lutea and Endometrium

Uterine tissue was collected from intact pregnant rats on days 4, 10-15, 18, and 22 of pregnancy and day 2 postpartum and from rats on day 22 of pregnancy after ovariectomy (day 9) and progesterone-estrogen treatment. Placental, cervical, mammary, and pituitary tissues were collected from intact pregnant rats on day 22. Ovarian tissue was collected from intact pregnant rats on days 15, 20, and 22. These tissues were evaluated for relaxin immunostaining at the light microscope level using an antiserum to purified rat relaxin and the avidin biotin immunostaining technique. Since the corpus luteum is the major source of relaxin in the rat, this tissue was used as a positive control. Relaxin immunostaining in the corpus luteum was observed in a discrete region of the cytoplasm. This pattern of staining corresponded with the discrete clustering of relaxin-containing secretory granules found in the rat luteal cells. Relaxin was not observed in the day 22 placenta, cervix, mammary gland, pituitary gland, or day 4-13 pregnant uterus. Relaxin immunostaining was detected in endometrial epithelial cells on days 14-22 of pregnancy and day 2 postpartum. Relaxin immunostaining was more evident at implantation sites than between implantation sites. Antimesometrial epithelial cells at implantation sites contained relaxin immunostaining. The mesometrial surface, which consists of the placenta and decidualized endometrium, did not contain relaxin immunostaining. Relaxin immunostaining was also present in the endometrial epithelial cells of the day 22 pregnant rats that had been ovariectomized on day 9 and given subsequent replacement therapy with ovarian steroids. The presence of relaxin immunostaining in the ovariectomized rat indicates the endometrium is not sequestering relaxin secreted from the corpus luteum. These data provide evidence that the pregnant rat endometrium is a source of relaxin in addition to the corpus luteum. The appearance of relaxin in endometrial epithelial cells after implantation and its prominence at implantation sites may indicate that locally secreted conceptus factors stimulate endometrial relaxin synthesis.
Measurement and Analysis of Interconnect Crosstalk Due to Single Events in a 90 nm CMOS Technology

The presence of single event (SE) induced interconnect crosstalk has been measured and demonstrated experimentally using single and two photon laser absorption techniques in the IBM 90 nm CMOS9SF process. The dependency of SE interconnect crosstalk on the interconnect length and on the amount of deposited charge has been quantified through 3D mixed-mode simulations at this technology for two different supply voltages. Experimental and simulation results show this effect to increase the cross-section susceptible to SEs requiring careful design considerations to assure desired hardness levels.
An alternate perspective on the opening and closing of the intracratonic Purana basins in peninsular India

Purana basins in India are Proterozoic in age, filled with mostly marine, deltaic, and fluvial sediments, with some alluvial fan deposits in the basin margins. The basin fill is largely undeformed and unmetamorphosed, and the basins occur in many shallow (<5 km), large and small depressions in the Archean-Paleoproterozoic cratons in peninsular India. An understanding of the reasons for the opening and closing of these intracratonic basins is elusive, far more so than that of the better-studied Phanerozoic intracratonic basins in the world. On the basis of meager, but robust new data, published in this century on the Purana basins and their host cratons’ lithostratigraphy, paleomagnetism, seismic images, geochronology, and paleontology, we propose a scenario of their opening and closing related to the assembly and disassembly of the supercontinents Kenorland, Columbia, and Rodinia. The Marwar and the Bundelkhand cratons occur in the western and northern Indian blocks, respectively. The southern Indian Block consists of the Singhbhum, Bastar, Eastern Dharwar, and Western Dharwar cratons; these had amalgamated by ca. 2.5 Ga, but split and re-amalgamated along the western margin of the Bastar craton ca. 1.6 Ga. These three blocks, and East Antarctica, were assembled ca. 1000 Ma along the Aravalli-Delhi Fold Belt, Central Indian Tectonic Zone, and the Eastern Ghats Mobile Belt, as part of Rodinia. There are three sets of Purana basins. The oldest set (Papaghni-Chitravati; Kaladgi-Badami; Lower Vindhyan; Gwalior-Bijawar-Sonrai) opened diachronously after 2.0 Ga and closed by 1.55 Ga. Others (Chhattisgarh; Indravati; Khariar;Ampani;Albaka; Mallampalli; Kurnool; Bhima; etc.) opened after the 1.6 Ga amalgamation event in the southern Indian block, and closed shortly after the 1000 Ma collision of East Antarctica with India. In the northern Indian block, the upper Vindhyan basin likely opened after 1.4 Ga. Sedimentation lingered in some of these basins for some time after 1000 Ma but ceased at the latest by 900 Ma. The Marwar basin in the western Indian block opened ca. 750 Ma, after the emplacement of the Malani Igneous Suite, and sedimentation ceased by 520 Ma, before the Cambrian Explosion. We propose that the three crustal blocks were largely separate between ca. 2.0 and 1.0 Ga but may have collided with and separated from each other from time to time. Minor fracturing in the cratons, entirely within the crust, caused them to have uneven topography. The resulting depressions were filled with sediments as sea level rose; they sagged under the sediment load and as a result of far-field effects of packing and unpacking of large landmasses (Kenorland, Columbia, and Rodinia). Ensuing dynamic topography and sea level fluctuations gave rise to the opening and closing of the Purana basins and their sediment fills.
Mutational analysis of transmembrane histidines in the amiloride-sensitive Na+/H+ exchanger

The histidine-reactive reagent, diethyl pyrocarbonate (DEPC) inhibits the human amiloride-sensitive Na+/H+ exchanger (NHE1) in stably transfected fibroblasts. NHE1 was protected by cimetidine and amiloride from DEPC, and DEPC inhibition was reversed with hydroxylamine, suggesting a role for critical histidine groups in NHE activity. We replaced the histidines (H) in putative transmembrane domains (H35, H120, H349) with glycine (G) using site-directed mutagenesis. There was no significant change in NHE activity of the H120G; H349G; H120,349G; and H35,120,349G mutants compared with wild type. The 50% inhibition concentration values for amiloride, ethyl isopropyl amiloride (EIPA), and cimetidine of the H349G mutant were significantly increased compared with the wild-type NHE1. We also examined the DEPC effect on the transport activity of the triple histidine mutant (H35,120,349G) and found that NHE1 activity was still inhibited by DEPC with reversal by hydroxylamine and protected by amiloride and cimetidine. Kinetic analysis of DEPC inhibition indicated that two "critical" histidine residues are required for NHE transport activity. Substitutions of H349 with asparagine (N), glutamine (Q), serine (S), tyrosine (Y), valine (V), leucine (L), and phenylalanine (F) were also examined. There were no changes in NHE activity of these mutants compared with wild type. The H349G and H349L mutants became more resistant to amiloride, whereas the H349Y and H349F mutants became more sensitive to amiloride. The H349S (mimics NHE3) and H349Y (mimics NHE4) mutations had only modest effects on amiloride sensitivity. These results indicate that H349 affects the interaction of NHE1 with its inhibitors, even though substitutions at this site, per se, do not appear to explain the differences in amiloride sensitivity between different NHE isoforms. Despite clear-cut effects of the H349G mutation on the competitive interaction of NHE1 with cimetidine and EIPA, this mutation did not affect the affinity of NHE1 for its cationic substrates (Na+, Li+).
Muscle temperature of mammals: cooling impairs most functional properties

Our purpose was to study the effect of a decrease in skeletal muscle temperature on single and repeated shortening, isometric, and lengthening contractions of mammalian skeletal muscles. Fast extensor digitorum longus muscles of mice were studied in situ and in vitro at 25 and 35 degrees C. No difference in isometric force was observed, but maximum and sustained powers were reduced by 40 and 62%, respectively. With cooling, maximum power absorption, which is proportional to the external work required to lengthen the muscle, increased significantly at each velocity of lengthening from 0.5 to 4.0 optimum fiber length/s. The 10 degrees C decrease in muscle temperature produced a decrease in power that was primarily a result of the decrease in the velocity of shortening, whereas the increase in power absorption was likely due to an increase in the number of strongly bound cross bridges resulting from a decreased rate of detachment. During voluntary exercise at decreased muscle temperatures, maximum and endurance performances are inevitably impaired by the decreases in maximum and sustained power of individual motor units.
Acceptorless Alkane Dehydrogenation Catalyzed by Iridium CCC-Pincer Complexes

Iridium complexes of CCC-pincer bis-N-heterocyclic carbenes, including a newly synthesized trifluoromethyl-substituted complex, were examined as catalysts for the acceptorless dehydrogenation of cyclooctane and n-undecane. Up to 103 turnovers were observed for the dehydrogenation of cyclooctane, and up to 97 turnovers were observed for the dehydrogenation of n-undecane. The catalysts showed high initial turnover frequencies, followed by a gradual loss of activity over 24 h. Experiments indicate that this loss of activity is due to catalyst decomposition rather than product inhibition. Stoichiometric reactivity was investigated for the precatalysts, focusing on the synthesis of dihydride and trihydride complexes as well as the dissociation and addition of neutral ligands.
H2S, a gasotransmitter for oxygen sensing in carotid body. Focus on “Endogenous H2S is required for hypoxic sensing by carotid body glomus cells”

MANY, IF NOT ALL, TISSUES possess the ability to sense hypoxia, and most tissues respond to hypoxia by reducing energy expenditure as a form of self-preservation. The carotid body, however, rapidly responds to hypoxic conditions by initiating cardiorespiratory reflexes in order to increase ventilation and systemic delivery of oxygen rather than initiating mechanisms for local conservation. The carotid body is made up of two types of cells, neuron-like glomus (type 1 cells) and glia-like sustentacular (type II) cells. The glomus cells were identified as the chemoreceptive component of the carotid body nearly 40 years ago in a seminal study by Verna and colleagues (8). Since then, much of the research on the carotid body has been devoted to understanding how glomus cells sense hypoxia and identifying the molecular components of this process. Following the identification of oxygen-sensitive K channels in glomus cells (3), a model of carotid body responsiveness termed the “membrane hypothesis” was developed. Briefly, hypoxia leads to inhibition of K channels, causing membrane depolarization, opening of voltage-dependent Ca 2 channels (VDCC), increasing cytosolic Ca 2 concentration ([Ca 2 ]cyt), and triggering the release of neurotransmitters (7,