cssi/SciSciGPT-SciSciNet huggingface dataset:
Variation in propagule mass and its effect on carbon assimilation and seedling growth of red mangrove (Rhizophora mangle) in Florida, USA

We investigated the intraspecific variation in propagule mass within red mangrove (Rhizophora mangle) and its effect on carbon assimilation and seedling growth. Propagule sizes of red mangrove varied considerably at all three study sites along the south-eastern coast of Florida, with propagule fresh mass from 3.9 to 20.7 g for the scrub form and from 5.3 to 35.8 g for the tall form. Highly significant correlations were observed between propagule length and fresh weight at all three study sites and for two growth forms. The scrub form had significantly smaller propagules than the tall form. A greenhouse study showed that CO2 assimilation rates were not correlated with propagule mass, but total leaf area per plant increased significantly with increasing initial propagule mass in all three family lines of both the scrub and tall forms. Consequently, total carbon fixation rate by each seedling increased significantly with increasing propagule fresh weight in all cases, and the biomass increment significantly increased with increasing mass. Relative growth rate, however, was not correlated with propagule mass. The differences in leaf areas and biomass accumulation among seedlings from different sizes of propagules seem to have resulted from the differences in maternal reserve of hypocotyls. The considerable intraspecific variation in propagule size observed for red mangrove may have a significant effect on seedling growth and competitive ability.
Structural origin of large gas cavities in the Big Obsidian Flow, Newberry Volcano

Mesoscopic structures in four large cavities on the Big Obsidian Flow, OR, USA, provide evidence of links between large-scale surface folding, cavity formation, and hazardous explosive activity originating from within the flow. Stereographic analysis of flow banding, stretched bubble lineation, striations, and mesoscopic fold axes indicates that three of the cavities are near-cylindrical folds. Cavity fold axes are oriented parallel to large-scale compressional flow ridge axes, suggesting that cavities form in response to shortening during flow advance. Large surface folds develop as the upper 10 m of the cooler flow surface buckles when the flow front cools, slows, and stalls against topographic barriers. Void space is created in fold hinges as obsidian layers shear past each other and pull apart. The resultant cavities may serve as reservoirs for exsolved volatiles or surface water which may later vent explosively to form explosion craters on the flow surface.
Interface Effects in Multiple Scattering by Large, Low-Refracting, Absorbing Particles*

Earlier approximations for multiple scattering by uncorrelated random distributions of large, low-refracting, absorbing particles are generalized by retaining the internal backscattered flux for the case of negligible coherent reflection. For a plane wave normally incident on a slab-region distribution, we obtain more complete results for the flux into a detecting cone at an arbitrary angle of observation, in terms of one-particle scattering functions, scatterer concentration, and distribution thickness. The approximations cover the full range of concentration; although the results near full packing are in general physically unrealizable, they are shown to be in accord with elementary physical considerations. The special forms for the total transmitted flux and total backscattered flux are similar to forms obtained by the diffusion-equation approach. However, the present development, based on averaging the absolute square of the solution of the wave equation for a large number of particles, provides approximations for the bulk parameters and for the flux in terms of results for an isolated scatterer.
Behavioral Maintenance: A Closer Look

TOPIC Behavior maintenance. PURPOSE To discover the descriptive picture of how an individual with type 2 diabetes self-managed and adapted the necessary behavior changes into her daily lifestyle. SOURCES Personal research and literature review. CONCLUSION Behavioral maintenance to self-manage a specific regimen for people with type 2 diabetes is complex and difficult. It is important for nurses "not to jump to conclusions" and assume the client has not made the necessary changes to incorporate the behavior changes into a life style routine. Nurses need to be cognizant of the differences and unique situations of their clients when teaching them about managing their disease.
Second order 'flavor' perturbation theory for the baryons

We argue that second order flavor perturbation theory may still have some interesting things to say about low energy QCD. Application is made to the technical, but important, question of cleanly extracting the quark mass difference ratio R= [ms−(md+mu)/2]/(md−mu) from the experimental baryon masses. We also give a group theoretical decomposition of the second order contributions according to the SU(3) representation of the intermediate states. This is used to provide constraints on quantum mechanics type models of the nucleon.
Packing and discharge in injection molding

In a reciprocating-screw injection-molding machine, the screw or plunger forces the plastic into the mold. It remains in the forward position under pressure for a fixed time during which plastic flow into the mold or ‘packing’ takes place. After the timer runs out, the screw moves back while rotating thus releasing the pressure on the plastic in the mold. At this time, if the gate has not frozen, flow of plastic out of the mold or ‘discharge’ takes place. In this study, clear rigid PVC, poly (vinyl chloride), was molded with varying amounts of packing and discharge. Photoelastic stress patterns for parts observed between cross-polaroids suggested that packing and discharge give rise to high frozen stresses due to molecular orientation in the gate area. Mechanical strength tests on the molded parts show that these high stresses are a source of weakness. Short forward times for the plunger significantly improve the mechanical properties of the parts in the gate area and at the same time have a significant influence on part dimensions, especially in the gate vicinity. Laminations observed at the gate interface can also be reduced by controlling the extent of molecular orientation introduced by packing and discharge.
A way of being in the playroom: Experience-expression congruence model (EECM).

Congruence, in conjunction with unconditional positive regard and empathic understanding, is considered one of the fundamental attitudinal conditions that must be internally experienced and externally expressed by play therapists in order to facilitate growth in child-centered play therapy. The experience-expression congruence model (EECM) helps play therapists understand the nature of congruence, recognize the impact of congruence in play-therapy sessions, and intentionally use the therapist’s awareness of congruence to benefit the client. The EECM is a two-phase model that challenges play therapists to consider their own personal levels of authenticity and implications for working with children in play therapy.
Steady state and dynamic analysis of a bench-scale injected pultrusion process

This article examines the operational characteristics of the injected pultrusion process using a bench-scale unit. The distributed, non-linear nature of the process makes routine process operations and quality control difficult. In our prior work [Comput. Chem. Engng. 4 (2000) 1961], a three-dimensional dynamic model based on mass, momentum and energy transport was developed. This processing model is validated using experimental data from the bench scale unit. Experiments were designed to verify the steady state and dynamics of the process model. The model predictions were validated with the primary measurements of temperature and pressure profiles, and cure, as well as secondary measurements of pull force and part exit temperature. While there was good agreement with the observed data, the experimental results indicate the need for better pull-force models and improved measurement and feedback stabilization techniques.
Resonant Laser Ablation: Semiquantitative Aspects and Threshold Effects

In this paper we present a survey of RLA (Resonant Laser Ablation) attributes and applications. We describe the use of RLA for the analysis of trace components in a variety of samples, including copper, rhenium and nickel. Semiquantitative analysis (error estimates on concentration are≃a factor of 5) is demonstrated with good selectivity and excellent sensivity. The use of RLA for spectroscopy of small or very dilute samples is also noted
Expanding the 43C9 class of catalytic antibodies using a chain-shuffling approach

Abstract We employed a chain-shuffling technique to determine if the light chain of the catalytic antibody, 43C9, provides the best partner for the 43C9 heavy chain. Previously, we reported construction and screening of a 43C9 HC CROSS library, where the 43C9 heavy-chain gene was crossed with a library of light-chain genes in a λ bacteriophage system. The library contained a high frequency of reconstituted antibodies recognizing the transition-state analogue. Here, we report the isolation and characterization of four of these clones. Recovered light-chain proteins share 92–96% sequence identity to the 43C9 light-chain protein. Somatic mutations of these light chains occur randomly at positions distant from the active site. Residues required for binding and catalysis were conserved. Mutations affected the topology of the binding site. Nevertheless, catalysis was not affected. Isolation of these light chains suggests the best partner for the 43C9 heavy chain is the original light chain. These clones attempt to broaden a class of 43C9-like antibodies, where the catalytic residues, His91 and Arg96, have been reproducibly selected. Similar catalytic properties between the 43C9-like antibodies suggests binding has been optimized, thus further maturation of the light chain would not lead to a better catalyst. To improve catalysis, other approaches must be considered. Crossing the 43C9 heavy-chain gene with a library of light-chains yields light-chain proteins sharing 92–96% sequence identity to 43C9. These clones attempt to broaden a class of 43C9-like antibodies, where the catalytic residues, His91 and Arg96, have been reproducibly selected. Similar catalytic properties between the 43C9-like antibodies suggests binding has been optimized, thus further maturation of the light chain would not lead to a better hydrolytic antibody.
Designing Radiation Resistance in Materials for Fusion Energy

Proposed fusion and advanced (Generation IV) fission energy systems require high-performance materials capable of satisfactory operation up to neutron damage levels approaching 200 atomic displacements per atom with large amounts of transmutant hydrogen and helium isotopes. After a brief overview of fusion reactor concepts and radiation effects phenomena in structural and functional (nonstructural) materials, three fundamental options for designing radiation resistance are outlined: Utilize matrix phases with inherent radiation tolerance, select materials in which vacancies are immobile at the design operating temperatures, or engineer materials with high sink densities for point defect recombination. Environmental and safety considerations impose several additional restrictions on potential materials systems, but reduced-activation ferritic/martensitic steels (including thermomechanically treated and oxide dispersion–strengthened options) and silicon carbide ceramic composites emerge as robust structural...
Analysis of a mesoscale infiltration and water seepage test in unsaturated fractured rock: Spatial variabilities and discrete fracture patterns.

Abstract A mesoscale (21 m in flow distance) infiltration and seepage test was recently conducted in a deep, unsaturated fractured rock system at the crossover point of two underground tunnels. Water was released from a 3 m × 4 m infiltration plot on the floor of an alcove in the upper tunnel, and seepage was collected from the ceiling of a niche in the lower tunnel. Significant temporal and (particularly) spatial variabilities were observed in both measured infiltration and seepage rates. To analyze the test results, a three-dimensional unsaturated flow model was used. A column-based scheme was developed to capture heterogeneous hydraulic properties reflected by these spatial variabilities observed. Fracture permeability and van Genuchten α parameter [van Genuchten, M.T., 1980. A closed-form equation for predicting the hydraulic conductivity of unsaturated soils. Soil Sci. Soc. Am. J. 44, 892–898] were calibrated for each rock column in the upper and lower hydrogeologic units in the test bed. The calibrated fracture properties for the infiltration and seepage zone enabled a good match between simulated and measured (spatially varying) seepage rates. The numerical model was also able to capture the general trend of the highly transient seepage processes through a discrete fracture network. The calibrated properties and measured infiltration/seepage rates were further compared with mapped discrete fracture patterns at the top and bottom boundaries. The measured infiltration rates and calibrated fracture permeability of the upper unit were found to be partially controlled by the fracture patterns on the infiltration plot (as indicated by their positive correlations with fracture density). However, no correlation could be established between measured seepage rates and density of fractures mapped on the niche ceiling. This lack of correlation indicates the complexity of (preferential) unsaturated flow within the discrete fracture network. This also indicates that continuum-based modeling of unsaturated flow in fractured rock at mesoscale or a larger scale is not necessarily conditional explicitly on discrete fracture patterns.
Trace elements in migrating blue-winged teal: Seasonal-, sex- and age-class variations

Migrating blue-winged teal (Anas discors) were collected in April (n = 48) and September (n = 53) 1983 on the Southern High Plains Region of Texas. Liver and breast muscle were analyzed for 14 trace elements, and tibias were analyzed for Pb content. Data were analyzed statistically to determine differences in concentrations between seasons, sexes and age classes. Concentrations of B, Cr, Mo, Pb, Zn, Hg, Cu and Se in livers, and of B, Cu, Mo, Pb and Se in muscle, were greater in autumn- than in spring-migrating blue-winged teal. Lead concentrations in livers, muscles and tibias reflected apparently low-level, chronic, oral exposure to this metal. Concentrations of Cr, Ni, Pb and Cu in livers, and of Cr and Zn in muscle, were greater in males than females. Greater Cd concentrations in livers of adults than in juveniles were attributed to the persistence of Cd in tissues. The trace metal concentrations we observed in our blue-winged teal samples generally were not sufficiently high to produce adverse physiological or reproductive effects.
Visualization of Automated and Manual Trajectories in Wide-Area Motion Imagery

The task of automated object tracking and performance assessment in low frame rate, persistent, wide spatial coverage motion imagery is an emerging research domain. The collection of hundreds to tens of thousands of dense trajectories produced by such automatic algorithms along with the subset of manually verified tracks across several coordinate systems require new tools for effective human computer interfaces and exploratory trajectory visualization. We describe an interactive visualization system that supports very large gig pixel per frame video, facilitates rapid, intuitive monitoring and analysis of tracking algorithm execution, provides visual methods for the inter comparison of very long manual tracks with multi segmented automatic tracker outputs, and a flexible KOLAM Tracking Simulator (KOLAM-TS) middleware that generates visualization data by automating the object tracker performance testing and benchmarking process.
AN EXPERIMENTAL TEST OF CHARACTER DISPLACEMENT'S ROLE IN PROMOTING POSTMATING ISOLATION BETWEEN CONSPECIFIC POPULATIONS IN CONTRASTING COMPETITIVE ENVIRONMENTS

Ecological character displacement takes place when two closely related species co-occur in only part of their geographical range, and selection to minimize competition between them promotes divergence in resource-use traits in sympatry but not in allopatry. Because populations sympatric with the heterospecific competitor will experience a different competitive environment than conspecific populations in allopatry, conspecific populations from these two competitive environments will also diverge in resource traits as an indirect consequence of interspecific ecological character displacement. Ultimately, ecologically dependent postmating isolation may arise between conspecific populations from these divergent competitive environments if offspring produced by matings between them are competitively inferior in either type of competitive environment. Yet, there are no direct tests of character displacement's role in initiating such postmating isolation. Here, we present a test by comparing the phenotypes and performances of spadefoot toad tadpoles produced from between-competitive-environment (BCE) matings versus those produced from within-competitive-environment (WCE) matings. When raised with naturally occurring competitors, BCE offspring grew significantly less and were significantly smaller than WCE offspring. BCE offspring generally performed worse even when raised alone, suggesting that they may have harbored intrinsic genetic incompatibilities. Moreover, the difference in growth and body size of BCE versus WCE offspring was significantly greater when each was raised with competitors than when each was raised alone, suggesting that BCE tadpoles were competitively inferior to WCE tadpoles. Presumably, this enhanced difference arose because BCE tadpoles produced an intermediate resource-use phenotype that is less well adapted to either competitive environment. Because larval size is under strong, positive, directional selection, reduced growth and size of BCE offspring may diminish gene flow between populations in divergent competitive environments, thereby generating postmating isolation. Thus, postmating isolation between conspecific populations, and possibly even speciation, may arise as a by-product of interactions between species.
Why Not Semijoins for Streams, When Distributed?

This paper addresses the semijoin-based window join algorithm over distributed data streams. In distributed stream query processing, data streams arriving at remote sites need to be shipped to the processing site for query execution. This typically introduces high communication overhead over the network. Our observation is that semi- join, effective to reduce communication overhead in distributed database query processing, can be also effective in distributed stream query processing. The challenge, of course, lies in the streaming nature of tuples, the processing of which is fundamentally different from processing a set of tuples. We address this challenge by first adapting the window-based stream join to a distributed environment. The resulting join algorithm (called simple join) uses the idea of exporting a window to the query processing site. We then adopt the semijoin to reduce the communication overhead (in return for a marginal increase of the processing overhead). The resulting semijoin-based join algorithm uses the ideas of a mirror window and a partial tuple. That is, it creates a copy of a remote window at the processing site and sends a partial tuple to probe for matching tuples before sending a full tuple. Finally, we analyze the two join algorithms using our proposed cost models and verify the analysis results through a set of experiments.
Influence of catchment-scale military land use on stream physical and organic matter variables in small southeastern plains catchments (USA)

We conducted a 3-year study designed to examine the relationship between disturbance from military land use and stream physical and organic matter variables within 12 small (<5.5 km2) Southeastern Plains catchments at the Fort Benning Military Installation, Georgia, USA. Primary land-use categories were based on percentages of bare ground and road cover and nonforested land (grasslands, sparse vegetation, shrublands, fields) in catchments and natural catchments features, including soils (% sandy soils) and catchment size (area). We quantified stream flashiness (determined by slope of recession limbs of storm hydrographs), streambed instability (measured by relative changes in bed height over time), organic matter storage [coarse wood debris (CWD) relative abundance, benthic particulate organic matter (BPOM)] and stream-water dissolved organic carbon concentration (DOC). Stream flashiness was positively correlated with average storm magnitude and percent of the catchment with sandy soil, whereas streambed instability was related to percent of the catchment containing nonforested (disturbed) land. The proportions of in-stream CWD and sediment BPOM, and stream-water DOC were negatively related to the percent of bare ground and road cover in catchments. Collectively, our results suggest that the amount of catchment disturbance causing denuded vegetation and exposed, mobile soil is (1) a key terrestrial influence on stream geomorphology and hydrology and (2) a greater determinant of in-stream organic matter conditions than is natural geomorphic or topographic variation (catchment size, soil type) in these systems.
Postconditioning attenuates myocardial ischemia-reperfusion injury by inhibiting events in the early minutes of reperfusion.

Objective: We previously showed that brief intermittent ischemia applied during the onset of reperfusion (i.e., postconditioning) is cardioprotective in a canine model of ischemia–reperfusion. This study tested the hypothesis that the early minutes of reperfusion (R) during which postconditioning (Post-con) is applied are critical to its cardioprotection. Methods: In anesthetized open-chest rats, the left coronary artery (LCA) was occluded for 30 min and reperfused for 3 h. All rats were randomly divided into six groups: Control ( n =8): no intervention at R; Ischemic preconditioning (IPC) ( n =8): the LCA was occluded for 5 min followed by 10 min of R before the index occlusion; Post-con 1 ( n =8): after LCA occlusion, three cycles of 10 s R followed by 10 s LCA re-occlusion were applied during the first minute of R; Post-con 2 ( n =8): Six cycles of 10 s R and 10 s re-occlusion were applied during the first 2 min of R; Delayed Post-con ( n =8): the ligature was loosened for full reflow for the first minute of R, after which the three-cycle Post-con algorithm was applied; Sham ( n =6): the surgical procedure was identical to other groups, but the LCA ligature was not ligated. Results: Infarct size (TTC staining) was 23% smaller in Post-con 1 (40±2%*) than in Control (52±3%), confirmed by plasma creatine kinase activity (18±2* vs. 46±6 IU/g protein). There was no further reduction in infarct size with 6 cycles of Post-con (40±2.9%, p >0.05 vs. Post-con 1). Meanwhile, infarct size reduction was significantly greater in the IPC group (17±3%) than in Post-con1 ( p <0.01). The plasma lipid peroxidation product malondialdehyde (MDA, μM/ml) was less after R in IPC and Post-con 1 (0.8±0.07* and 0.8±0.06*) vs. Control (1.21±0.08), consistent with a visual decrease in superoxide anion generation (dihydroethidium staining) in the AAR myocardium after 3 h of reperfusion. Neutrophil accumulation (myeloperoxidase activity, MPO, U/100 g tissue) in the AAR was less in IPC (1.4±0.3*) and Post-con 1 (2.5±0.3*) vs. Control (5.5±0.6). The reductions in infarct size, creatine kinase, MDA and DHE staining were lost with delayed Post-con, while MPO activity remained lower than in Control (3.2±0.4*). Conclusions: (1) Post-con at onset of R reduces myocardial injury; (2) cardioprotection may be mediated, in part, by inhibiting oxidant generation and oxidant mediated injury; (3) the first minute of R in the rat model is critical to cardioprotection by Post-con; and (4) cardioprotection by Post-con may be independent of neutrophil accumulation in AAR. * p <0.05 Post-con vs. Control.
Distribution of 11-cis LRAT, 11-cis RD and 11-cis REH in bovine retinal pigment epithelium membranes

Our recent finding of the co-localization of 11-cis retinyl esters and 11-cis retinyl ester hydrolase (11-cis REH) activity in bovine retinal pigment epithelium (RPE) plasma membrane (PM) has led us to explore the possibility that the PM may provide 11-cis retinal for rhodopsin regeneration. In the RPE, visual chromophore is synthesized via a membrane associated 11-cis retinol dehydrogenase (11-cis RD). Accordingly, bovine RPE membranes enriched with either endoplasmic reticulum (ER) or plasma membrane (PM) enzyme markers were prepared and assayed for visual cycle enzyme activities. Pronounced 11-cis RD activity was associated with both ER- and PM-enriched membrane fractions. In contrast, 11-cis REH activity was mostly recovered in PM-enriched fractions while LRAT activity was found only in ER-enriched membranes. The finding that both 11-cis retinol and 11-cis retinal can be produced at the PM of the bovine RPE strongly suggests that 11-cis retinyl esters at this subcellular locale serve as a precursor of visual chromophore for pigment regeneration.
Program characteristics and residents' length of stay in alcoholism halfway houses.

Data from 23 alcoholism halfway houses are analyzed to assess the relationship of organizational and programmatic variables to clients' average length of stay. Results indicate that programs which ...
Conventional Protein Kinase C-α (PKC-α) and PKC-β Negatively Regulate RIG-I Antiviral Signal Transduction

Retinoic acid-inducible gene I (RIG-I) is a key sensor for viral RNA in the cytosol, and it initiates a signaling cascade that leads to the establishment of an interferon (IFN)-mediated antiviral state. Because of its integral role in immune signaling, RIG-I activity must be precisely controlled. Recent studies have shown that RIG-I CARD-dependent signaling function is regulated by the dynamic balance between phosphorylation and TRIM25-induced K₆₃-linked ubiquitination. While ubiquitination of RIG-I is critical for RIG-I's ability to induce an antiviral IFN response, phosphorylation of RIG-I at S₈ or T₁₇₀ suppresses RIG-I signal-transducing activity under normal conditions. Here, we not only further define the roles of S₈ and T₁₇₀ phosphorylation for controlling RIG-I activity but also identify conventional protein kinase C-α (PKC-α) and PKC-β as important negative regulators of the RIG-I signaling pathway. Mutational analysis indicated that while the phosphorylation of S₈ or T₁₇₀ potently inhibits RIG-I downstream signaling, the dephosphorylation of RIG-I at both residues is necessary for optimal TRIM25 binding and ubiquitination-mediated RIG-I activation. Furthermore, exogenous expression, gene silencing, and specific inhibitor treatment demonstrated that PKC-α/β are the primary kinases responsible for RIG-I S₈ and T₁₇₀ phosphorylation. Coimmunoprecipitation showed that PKC-α/β interact with RIG-I under normal conditions, leading to its phosphorylation, which suppresses TRIM25 binding, RIG-I CARD ubiquitination, and thereby RIG-I-mediated IFN induction. PKC-α/β double-knockdown cells exhibited markedly decreased S₈/T₁₇₀ phosphorylation levels of RIG-I and resistance to infection by vesicular stomatitis virus. Thus, these findings demonstrate that PKC-α/β-induced RIG-I phosphorylation is a critical regulatory mechanism for controlling RIG-I antiviral signal transduction under normal conditions.
PCO-Based Synchronization for Cognitive Duty-Cycled Impulse Radio Sensor Networks

The pulse coupled oscillator (PCO) system of Mirollo and Strogatz has been proposed as a robust, scalable synchronization scheme for impulse radio (IR-UWB) networks. In this paper, we map the parameter space for physical implementation of CMOS IR-UWB PCO radios into the traditional PCO mathematical model and show through comprehensive simulation that high-quality synchronization is easily achieved. We discuss practical implementation issues of PCOs for these radios and show that such systems can be created with extremely low cost and low complexity integrated components with acceptable synchronization performance. Finally, we demonstrate simple wireless synchronization of PCOs, and show that synchronization of such systems is robust in CMOS electronics.
13C-Enriched Carbonate in Mississippian Mud Mounds: Alamogordo Member, Lake Valley Formation, Sacramento Mountains, New Mexico, U.S.A.

ABSTRACT The origin of the carbonate mud constituting Paleozoic mid-shelf and deeper-water mud mounds has long been debated. Mississippian mud mounds and their laterally adjacent coeval inter-mound strata in the Lake Valley Formation are well exposed along cliff faces in south-central New Mexico. The mounds originated on erosional surfaces on a gently sloping ramp in 110 to 250 m water depth. Carbonate muds that constitute the inter-mound strata, mud mounds, and syndepositional neptunian dikes within the mounds are low-Mg calcite microspars with similar petrographic, cathodoluminescent, and fluorescent characteristics. Carbon and oxygen stable isotope analyses demonstrate that the microspars constituting the inter-mound, mound, and neptunian dikes have average 13C values of 2.6 ( = ±0.2), 3.4 ( = ±0.6), and 4.8 ( = ±0.3) PDB, respectively. Additionally, well preserved brachiopods from the inter-mound strata and from Muleshoe mud mound have 13C values markedly different from each other but similar to their surrounding microspars, i.e., brachiopod 's = 2.7 and 3.9 PDB, respectively. The stable-isotope distributions within each environment, similarity of values between microspar and brachiopod data from the same depositional environments, as well as agreement of 13C values with other investigations of coeval strata support the conclusion that the measured 13C values are essentially primary values. It is envisioned that 13C-enriched fluids sourced by bacterial fermentation in the subjacent strata rose into the mounds, some through neptunian dikes, and influenced the precipitation of the microspars in the mounds and dikes. Near the sediment-water interface, these fluids mixed with normal marine waters, thus precipitating the microspars, or their precursors, which have high 13C values that characterize the mud mounds. The inter-mound microspars and inter-mound brachiopods have the lowest 13C values and are in agreement with worldwide coeval marine calcites, that is, the inter-mound microspars formed under normal marine conditions. The high 13C values measured in all of the mound-related samples indicate that all mounds received a contribution of 13C-enriched waters. This relationship indicates that microspar precipitation in the mounds was associated with seepage of methanogenic fluids from the underlying strata.
Adaptive Lasso for Cox's proportional hazards model

SUMMARY We investigate the variable selection problem for Cox's proportional hazards model, and propose a unified model selection and estimation procedure with desired theoretical properties and computational convenience. The new method is based on a penalized log partial likelihood with the adaptively weighted L1 penalty on regression coefficients, providing what we call the adaptive Lasso estimator. The method incorporates different penalties for different coefficients: unimportant variables receive larger penalties than important ones, so that important variables tend to be retained in the selection process, whereas unimportant variables are more likely to be dropped. Theoretical properties, such as consistency and rate of convergence of the estimator, are studied. We also show that, with proper choice of regularization parameters, the proposed estimator has the oracle properties. The convex optimization nature of the method leads to an efficient algorithm. Both simulated and real examples show that the method performs competitively.
The horizontal brain slice preparation: a novel approach for visualizing and recording from all layers of the tadpole tectum

The Xenopus tadpole optic tectum is a multisensory processing center that receives direct visual input as well as nonvisual mechanosensory input. The tectal neurons that comprise the optic tectum a...
The effects of comparison shopping behaviour on dynamic pricing strategy selection in an agent-enabled e-market

E-buyers may use software agents, known as shopbots, to collect and display market data, make buying decisions, and execute sales transactions. E-sellers use pricebots to adjust prices based on market data and stored algorithms. We construct a simulator in which both buyers and sellers use agents. Specifically, we vary levels of comparison shopping, as represented by the extent of shopbot usage, and study the impact on the optimal selection of dynamic pricing strategies by sellers' pricebots. Results indicate that shopbot use and pricing strategy, their interaction, and the presence of a dominant seller significantly affect optimal pricing strategy.
The phytoplasma associated with ash yellows and lilac witches'-broom: ‘Candidatus Phytoplasma fraxini’

Phytoplasmas associated with the plant diseases ash yellows (AshY, occurring in Fraxinus) and lilac witches'-broom (LWB, occurring in Syringa) represent a putative species-level taxon. Phytoplasmal DNA from 19 ash or lilac sources across the known geographic range of AshY (71–113 °W) was examined to determine if AshY and LWB phytoplasmas are a coherent group, if variability exists in both conserved and anonymous DNA, and if variability in 16S rDNA is related to host or geographic origin. The 16S rRNA gene and the 16S-23S spacer were amplified using primer pair P1/P7 and analysed using 15 restriction enzymes. RFLPs were detected in digests obtained with Alul, Hhal or Taql, for a total of four RFLP profile types. Sequencing of the amplimers from strains AshY1T, AshY3, AshY5 and LWB3 (which represent the four 16S rDNA RFLP profile types) revealed only three positions in the 16S rRNA gene and one position in the 16S-23S spacer at which differences occurred; these were single nucleotide substitutions. Sequence homology between any two strains was >99.8%. A portion of a ribosomal protein operon, amplified with primer pair rpF1/R1 from each of the four strains noted above, was analysed with six restriction enzymes, resulting in the detection of two RFLP profiles with Msel. Southern analysis, utilizing two non-specific probes from other phytoplasma groups, revealed three RFLP profile types in anonymous chromosomal DNA of strains representing the four 16S rDNA genotypes. Two strains, AshY3 and LWB3, had unique combinations of characters in the various assays. On the basis of RFLP profiles, the strains from the other plants sampled comprised two groups. The grouping was not clearly related to host or geographic origin. The genome size of strain AshY3 was estimated from PFGE data to be 645 kbp. Phylogenetic analysis of a 1423 bp 16S rDNA sequence from strains AshY1T, AshY3, AshY5 and LWB3, together with sequences from 14 other mollicutes archived in GenBank, produced a tree on which the AshY and LWB strains clustered as a discrete group, consistent with previous analyses utilizing only type strain AshY1T. Thus, the AshY phytoplasma group is coherent but heterogeneous. The name ‘Candidatus Phytoplasma fraxini’ is proposed for this group.
Anomalous early aftershock decay rate of the 2004 Mw6.0 Parkfield, California, earthquake

[1] We analyze the seismicity rate immediately after the 2004 Mw6.0 Parkfield, California, earthquake from near-source seismograms. By scrutinizing high-frequency signals, we can distinguish mainshock coda from early aftershocks occurring as soon as 30 s after the mainshock. We find, as expected, that a significant fraction of aftershocks in the first few hours after the main shock are missing in the Northern California Seismic Network catalog. We observe a steady rate of aftershocks in the first 130 s, followed by a power-law decay of aftershock activity. Thus, there appears to be a distinct early stage of aftershock activity that does not fit the Omori's law with a constant p value, a phenomenon that we refer to as Early Aftershock Deficiency (EAD). Our observation suggests that mainshock rupture and aftershocks are distinct processes, not described by a single Omori's law. Several physical models of aftershocks can explain the EAD.
Soil‐ and plant‐water dynamics in a C3/C4 grassland exposed to a subambient to superambient CO2 gradient

Plants may be more sensitive to carbon dioxide (CO2) enrichment at subambient concentrations than at superambient concentrations, but field tests are lacking. We measured soil-water content and determined xylem pressure potentials and δ13C values of leaves of abundant species in a C3/C4 grassland exposed during 1997–1999 to a continuous gradient in atmospheric CO2 spanning subambient through superambient concentrations (200–560 µmol mol2−1). We predicted that CO2 enrichment would lessen soil-water depletion and increase xylem potentials more over subambient concentrations than over superambient concentrations. Because water-use efficiency of C3 species (net assimilation/leaf conductance; A/g) typically increases as soils dry, we hypothesized that improvements in plant-water relations at higher CO2 would lessen positive effects of CO2 enrichment on A/g. Depletion of soil water to 1.35 m depth was greater at low CO2 concentrations than at higher CO2 concentrations during a mid-season drought in 1998 and during late-season droughts in 1997 and 1999. During droughts each year, mid-day xylem potentials of the dominant C4 perennial grass (Bothriochloa ischaemum (L.) Keng) and the dominant C3 perennial forb (Solanum dimidiatum Raf.) became less negative as CO2 increased from subambient to superambient concentrations. Leaf A/g—derived from leaf δ13C values—was insensitive to feedbacks from CO2 effects on soil water and plant water. Among most C3 species sampled—including annual grasses, perennial grasses and perennial forbs—A/g increased linearly with CO2 across subambient concentrations. Leaf and air δ13C values were too unstable at superambient CO2 concentrations to reliably determine A/g. Significant changes in soil- and plant-water relations over subambient to superambient concentrations and in leaf A/g over subambient concentrations generally were not greater over low CO2 than over higher CO2. The continuous response of these variables to CO2 suggests that atmospheric change has already improved water relations of grassland species and that periodically water-limited grasslands will remain sensitive to CO2 enrichment.
Syntactically Complex Vocal Systems

The temporal patterning of vocal communication signals is widespread and suggests parallels to human linguistic capacities. Two levels of syntactic structure may be defined: phonological and lexical. Lexical syntax involves the patterning of meaningful units into longer, meaningful sequences, as in human language. In phonological syntax, a sequence of otherwise meaningless sound units conveys meaning. The syntactic complexity of animal vocalizations has been measured using information theoretic analyses and formal grammars across a range of taxa. Birds and nonhuman primates have been the most extensively studied. Phonological syntax is common across a wide range of groups and can involve rule or rule-like organization of vocal sequences. Lexical syntax is very rare – having been observed only in nonhuman primates and then in a limited capacity that may lack open compositional rules.
Periodic Pulay method for robust and efficient convergence acceleration of self-consistent field iterations

Pulay's Direct Inversion in the Iterative Subspace (DIIS) method is one of the most widely used mixing schemes for accelerating the self-consistent solution of electronic structure problems. In this work, we propose a simple generalization of DIIS in which Pulay extrapolation is performed at periodic intervals rather than on every self-consistent field iteration, and linear mixing is performed on all other iterations. We demonstrate through numerical tests on a wide variety of materials systems in the framework of density functional theory that the proposed generalization of Pulay's method significantly improves its robustness and efficiency.
PHYSICAL GEOGRAPHY COMES OF AGE

Physical Geography was founded in 1980 and thus, in a traditional sense, comes of age in the year 2000. From modest beginnings, it has appeared bimonthly since 1993. Over the past 21 years, the journal has published 537 papers in 90 issues, including, in broadly defined and often overlapping categories, 182 in climatology, 200 in geomorphology, 94 in biogeography, 47 in hydrology and glaciology, and 14 strictly in general theory. Whereas the United States provides the principal regional focus of these papers, almost one-quarter of those published over the past decade have concerned other areas of the world. The content of papers over the period reflects the changing emphases and methods of physical geography and related fields, in turn a measure of the continuing vitality and relevance of the discipline. [Key words: physical geography, climatology, geomorphology, biogeography, hydrology, glaciology.]
Citizens Academies: Local Governments Building Capacity for Citizen Engagement

Many local governments have begun to offer civic education programs. These programs, known as citizens academies, teach residents about the functions of their local government and offer the promise of developing a more informed and ultimately better engaged citizenry. As a clear example of local government investing in civic capacity building, the emergent practice of citizens academies merits closer examination. This article offers a descriptive analysis of citizens academies in the United States and outlines key research questions going forward.
A synthetic polypeptide electrospun biomaterial.

Fiber mats of a synthetic anionic copolypeptide of l-glutamic acid and l-tyrosine (PLEY) have been produced by electrospinning, and physical, chemical, and biological properties of the fibers have been characterized in vitro. Fibers were obtained from polymer dissolved in water at concentrations of 20–60% (w/v) but not below this range. Applied voltage and spinneret-collector distance were also found to influence polymer spinnability. Oriented fibers were obtained by changing the geometry of the collector. Fiber diameter was measured by scanning electron microscopy (SEM). A common chemical reagent was used to cross-link polymers postspinning. Fiber solubility in aqueous solution varied as a function of cross-linking time. Cationic polypeptides labeled with a fluorescent dye became noncovalently associated with cross-linked fibers, enabling visualization by fluorescence microscopy. Spectroscopy provided information on polymer chain conformation in solution and in fibers. Degradation of cross-linked fibers ...
TEACHERS' ATTITUDES AND PRACTICES IN TEACHING CREATIVITY AND PROBLEM-SOLVING TO ECONOMICALLY DISADVANTAGED AND MINORITY CHILDREN

Ammons and Ammons (1962a, 1962b) evaluated the reaction of college students, many of whom were prospective teachers, to case history material describing family and life experiences of creative individuals. The students exhibited attitudes indicating that they would not reward and would even suppress, behaviors and environmental conditions which would support the development of creative abilities. The results of the present survey indicate a much more positive picture. There was considerable interest among 408 teachers from 5 cities, but little actual involvement, in teaching to foster creative thinking and problem-solving. Most teachers considered these areas significant in the education of economically disadvantaged and minority students. They expressed need for additional information about materials and methods to incorporate into the regular curriculum. Perhaps the vast emphasis on creativity by Torrance and others has produced these more favorable attitudes in teachers toward the nurturance of creativ...
Effect of fullerene intercalation on the conformation and packing of poly-(2-methoxy-5-(3'-7'-dimethyloctyloxy)-1,4-phenylenevinylene).

Photoluminescence (PL) and resonance Raman spectroscopy are used to track changes in the conformations and packing of poly-(2-methoxy-5-(3′-7′-dimethyloctyloxy)-1,4-phenylenevinylene) (MDMO-PPV) chains with the addition of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) molecules. PL lineshapes of MDMO-PPV thin films as a function of annealing time were first measured to determine the spectroscopic signatures of chain conformations and packing in the absence of PCBM. Annealing results in enhanced interchain interactions leading to red-shifts of PL 0–0 transitions by up to ∼300 cm–1 and apparent increases of the line shape Huang–Rhys factors. Wavelength-dependent PL lifetimes of as-cast and films annealed for short times (∼30 s) are nonexponential with an instrument-limited component of ∼100 ps and a ∼350 ps component. With longer annealing times, decays become single exponential with an average lifetime of ∼1 ns indicating that all excitations efficiently funnel to strongly coupled interchain sites. Add...
Managing Supply Chains in Emerging Markets

Manufacturing and retail companies, particularly those in North America, Europe and Japan, are moving towards global sourcing of their raw materials, components, and finished goods. Automobile firms were some of the initiators of this trend, followed by tool, steel and machinery companies such as Caterpillar, which currently sources products throughout Europe and North America. Still more recently apparel retailers have followed suit. Nike and Hush Puppies source products from Asia; in 1998 Laura Ashley announced plans to sell its European plants and do the same.
Laparoscopic Roux-en-"W" gastric bypass.

OBJECTIVES Roux-en-Y gastric bypass is the gold standard for treating morbid obesity in this country. The totally laparoscopic performance of this procedure, although quite demanding and technically difficult, has revolutionized it; and the demand for it has skyrocketed. We describe 2 cases where it became necessary to convert the Y into a "W" while performing the procedure. METHODS A laparoscopic Roux-en-Y gastric bypass was attempted on 2 patients, 1 male and 1 female, both with body mass indexes greater than 40. During creation of the side to side jejunojejunostomy, ie, the Y, it became obvious that stenosis or obstruction would result. This area was partially resected and an additional side to side anastomosis was formed, creating a "W." RESULTS The operative time was 205 minutes and 180 minutes, respectively, which compared favorably with the average operative time of 151 minutes in that quartile of patients (patients #101-#150). Both patients had normal upper gastrointestinal and small bowel contrast x-rays the day following surgery and were started on clear liquids. They were discharged later that day. Weight loss of 119 lb at 8 months and 80 lb at 6 months was documented, respectively, with no gastrointestinal sequelae. CONCLUSION If problems are encountered when creating the Y of a laparoscopic Roux-en-Y gastric bypass, a laparoscopic Roux-en-W may be performed. It appears safe, technically feasible, and with a postoperative course not unlike that of the standard approach.