cssi/SciSciGPT-SciSciNet huggingface dataset:
Kinetics of formation of silicides: A review

The kinetics of silicide growth are classified into three different categories: (a) diffusion controlled, (b) nucleation controlled, (c) others (reaction rate controlled). These are analyzed with the aim of understanding both the phenomenology of growth and the specific atomic mechanisms of phase formation. Diffusion-controlled growth is discussed with respect to the Nernst-Einstein equation. Stress relaxation is considered as a possible cause of reaction-rate control. The relative merits of two different types of marker experiments are compared. A few silicides are discussed in terms of what can be inferred about diffusion mechanisms. The competition between reaction-rate and diffusion control phenomena is shown to have specific effects on the sequence of phase formation; it is also related to the formation of some amorphous compounds. Reactions between silicon and alloyed metal films are used to illustrate the respective influences of mobility and driving force factors on the kinetics of silicide growth; they can also be used to underline the dominance of nucleation over diffusion in some silicide formation processes.
Impact of Managed Care on the Treatment, Costs, and Outcomes of Fee‐for‐Service Medicare Patients with Acute Myocardial Infarction

Objective To examine the effects of market-level managed care activity on the treatment, cost, and outcomes of care for Medicare fee-for-service acute myocardial infarction (AMI) patients.
Designing effective wine clubs: An analysis of the components of the winery wine club

This qualitative research study, utilising document analysis, identifies the various components of winery wine clubs available to prospective wine club members. This includes a frequency report of the wine club practices in use today as described by wine club brochures and supporting materials, as well as a verification of the wine club components described in industry literature. In addition, a check-list of 30 wine club components is presented. The study is useful for the wine club manager, the wine club member/customer, or organisations and individuals interested in winery marketing to advance the understanding of the span of choices in the marketplace.
Autonomy, Authority, and Answerability

One of the most difficult questions about authority is how deference to authority could possibly be compatible with autonomy. Autonomy seems to require that we engage in practical deliberation and come to our own decisions regarding how we will act. Deference to authority, by contrast, seems to require that we suspend deliberation and do what the authority commands precisely because he or she commands it. Authoritative directives purport to give us reasons to act that are, as HLA Hart puts it, both peremptory (they are intended to cut off or exclude our own deliberation) and content-independent (their normative force does not depend on the merits of the commanded course of action).1 One who responds to an authoritative directive by considering the pros and cons of the commanded act and then deciding (on the merits) to comply does not, properly speaking, obey or defer to authority, but continues to reserve ultimate practical authority for herself. And, one might wonder, why shouldn’t she? The conflict between autonomy and deference will seem all the more pressing if, like Robert P Wolff, we think of autonomy as a moral duty. If we are morally obligated to make up our own minds, the very idea of legitimate authority seems to come under threat. Many would challenge the idea that we have such a duty, at least thus described. Indeed, in a complex world we may sometimes have good reason (perhaps even an obligation) to defer to the judgements of others. Scott Shapiro, however, argues convincingly that the apparent conflict between autonomy and authority cannot be so easily resolved. Shapiro suggests that the puzzle is best understood as concerning claims about ‘the space of reasons’, and, more precisely, the question of whether one can ever justify one’s actions simply through appeal to authority.2 It might seem that another’s mere say-so is not the sort of thing appeal to which could possibly count as an adequate or even relevant reason for acting. If (2011) 2(1) Jurisprudence 161–179
On the Mechanism of Hydrogen Sulfide Removal from Moist Air on Catalytic Carbonaceous Adsorbents

Five carbonaceous adsorbents were studied as media for H2S removal from the gas phase. Materials were characterized using nitrogen adsorption, thermal analysis, XRF, and other standard methods. Hydrogen sulfide removal capacities were measured using the ASTM test. Then the species adsorbed/formed on the carbon surfaces were identified. The results showed that surface chemical features have a significant effect on the performance of materials as H2S adsorbents. To be adsorbed, hydrogen sulfide has to be oxidized to either elemental sulfur or sulfuric acid. The amount adsorbed and the extent of oxidation are governed by the surface pH and the dispersion of catalytic centers. Such centers can be nitrogen-containing basic groups and metals (iron and alkali and alkaline earth metals). A high volume of small micropores is also important. Contributing to a high dispersion of catalyst and providing adsorption centers for storage of oxidation products, these pores form specific oxidation microreactors.
Inverse M-matrices, II

This is an update of the 1981 survey by the first author. In the meantime, a considerable amount has been learned about the very special structure of the important class of inverse M-matrices. Developments since the earlier survey are emphasized, but we have tried to be somewhat complete; and, some results have not previously been published. Some proofs are given where appropriate and references are given for others. After some elementary preliminaries, results are grouped by certain natural categories.
A first-order global model of late Cenozoic climatic change II. Further analysis based on a simplification of CO2 dynamics

A model developed recently for the long-term variations of global ice mass, carbon dioxide, and mean ocean temperature through the late Cenozoic is simplified by hypothesizing a new equation for the CO2 variations containing one less adjustable parameter, but retaining the essential physical content of the previous equation (including nonlinearity and the potential for instability). By assuming plausible time constants for the glacial ice mass and global mean ocean temperature, and setting the values of six adjustable parameters (rate constants), a solution for the last 5 My is obtained displaying many of the features observed over this period, including the transition to the near-100 ky major ice-age oscillations of the late Pleistocene. In obtaining this solution it is also assumed that variations in tectonic forcing lead to a reduction of the equilibrium CO2 concentration (perhaps due to increased weathering of rapidly uplifted mountain ranges over this period). As a consequence of this CO2 reduction, the model dynamical system can bifurcate to a free oscillatory ice-age regime that is under the “pacemaker” influence of earthorbital (Milankovitch) forcing. Expanded discussions are given of the surface temperature variations accompanying the evolution of ice, CO2, and ocean temperature, and of the bifurcation properties of the model from both mathematical and physical viewpoints.
Cone mosaic in a teleost retina: No difference between light and dark adapted states

The mosaic arrangement of retinal cones in the eye of the African cichlid fish,Haplochromis burtoni, is the same in both light and dark adapted states. This is in contrast to Kunz' claim2 that the retinal mosaic pattern changes from a square to a row type during dark adaptation, in the guppy (Poecelia reticulata). Kunz' histological procedure may account for this difference in results.
The effect of hot-wet draw ratio on the coefficient of friction of wet-spun acrylic yarns

A series of wet-spun poly(acrylonitrile-co-vinyl acetate) yarns that were hot-wet stretched to a draw ratio range of 2.0 × −7.0 × were made for study of surface morphology and frictional characteristics. These yarns show an increase in draw ratio. The fiber to fiber coefficient of friction, measured parallel (line contact), and perpendicular (point contact), increases with draw ratio, giving an excellent correlation between orientation and friction. The effects of hot-wet draw ratio on the surface structure and its frictional behavior are discussed.
CIDS: cross-layer intrusion detection system for mobile ad hoc networks

In mobile ad hoc networks (MANET), lack of centralised monitoring point and lack of clear line of defense pose serious challenges for intrusion detection systems (IDS). In this paper, we present CIDS, a cross-layer based intrusion detection system with enhanced security performance in mobile ad hoc networks. We utilise cross-layer interactions to gather measurements from different protocol layers to detect attacks with increased accuracy. We present a case study to analyse packet drop detection in ad hoc networks using cross-layer techniques. Compared to traditional watchdog detection, CIDS is more effective in distinguishing network misbehaviour from genuine network irregularities. Simulation results based on extensive experiments illustrate the robustness and reliability of CIDS through higher detection rate and lower false positives.
Structure of an alpha-2,6-sialylated lipooligosaccharide from Neisseria meningitidis immunotype L1

The recent cloning of the lipooligosaccharide (LOS) a-2,3-sialyltransferase from Neisseria meningitidis immunotype L3 permitted us to examine other immunotypes for this structural gene. We identified the gene and measured the enzyme activity in the L1 immunotype strain which had previously been reported to lack sialic acid in its LOS because it contains a terminal alpha-linked galactose which was thought not to be an acceptor for the sialyltransferase. This finding prompted us to re-examine the structure of the LOS from the L1 immunotype, which revealed the presence of sialic acid on the terminal alpha-linked galactose. Oligosaccharides derived from the LOS were shown to be sialylated by composition and methylation analysis, mass spectrometry and nuclear magnetic resonance. The detailed structural analysis showed the sialic acid to occur only at 06 of the terminal a-D-galactopyranose residue of the alpha-D-Gal-1,4-beta-D-Gal-1,4-beta-D-glc trisaccharide (Pk epitope) chain of the LOS, in the alpha-D configuration. These data are the first report of a alpha-2,6-linked sialic acid in a bacterial LOS or lipopolysaccharide, and also the first report of a sialylated Pk epitope.
Direct measurement of turgor and osmotic potential in individual epidermal cells : independent confirmation of leaf water potential as determined by in situ psychrometry.

The pressure probe, which is routinely used to measure the turgor potential (Ψp) of individual epidermal cells in Tradescantia virginiana (L.), has also been used to sample small volumes of vacuolar fluid from these same cells (as low as 0.02 nl) for measurement of cellular solute (osmotic) potential (Ψs) in a micro freezing point osmometer. The water potential components Ψp and Ψo have been used to calculate the total water potential of individual epidermal cells (Ψcell) which has then been directly compared to the total leaf water potential (Ψleaf) measured psychrometrically. The relation of Ψleaf and Ψcell to leaf transpiration indicates that in T. virginiana, a relatively straightforward relation exists between the level of water flow through the leaf tissue, and the ΔΨ within the leaf, between two points along the water flow pathway. Substantial agreement was found between the two independent, in situ methods of measuring Ψ when extrapolated to zero transpiration conditions. These results are discussed with respect to the thermodynamics of water transport in plant tissues.
Ratcheting the evolution of multicellularity

Multicellularity is one of the major transitions that allowed the evolution of large, complex organisms, fundamentally reshaping Earth's ecology ( 1 ). Early steps in this process remain poorly resolved, because known transitions occurred hundreds of millions of years ago ( 2 ) and few transitional forms persist. It is generally accepted that the first steps toward multicellularity were the formation of cellular clusters, followed by the success or failure of those clusters depending on their traits. As clusters of cells adapted, cells lost their evolutionary autonomy, becoming mutually reliant parts in a new higher-level whole ( 1 , 3 ). This transition may be facilitated by a “ratcheting” process in which cells adopt traits that entrench them in a group lifestyle, stabilizing the group and paving the way for the evolution of multicellular complexity.
Response to critiques on ‘Omega-3 fatty acids for the treatment of depression: systematic review and meta-analysis’

Response to critiques on ‘Omega-3 fatty acids for the treatment of depression: systematic review and meta-analysis’
A simple index of standard operative temperature for mule deer and cattle in winter

Abstract 1. 1. Scientists often use ambient temperature, relative humidity, or windspeed alone to describe an animal's thermal environment. Standard operative temperature ( T es ) incorporates solar and thermal radiation, ambient temperature, and windspeed with a species' resistance to heat loss; thus it more accurately represents an animal's thermal environment. Standard operative temperature is not often recorded in the field because of instruments needed to measure short- and long-wave radiation. 2. 2. Our objective was to determine if regression equations could relate simple micrometeorological measurements to T es for mule deer and cattle in winter. 3. 3. Blackglobe and ambient temperatures, windspeed, net radiation, total radiation, albedo, and ground surface temperature were recorded during one winter in a field in Bozeman, Montana. We used species specific resistance values for mule deer and cattle in winter to calculate T es for both species. Then, we regressed T es with blackglobe and ambient temperatures, and windspeed. The mule deer regression model was applied to an independent data set to determine if it worked well under varying weather conditions. 4. 4. The mule deer and cattle regression models represented T es for both species well (adjusted R 2 0.96 and 0.94, respectively). The mule deer regression model also represented the independent data set well. Standard operative temperatures predicted by our model and those predicted by the independent data set were highly correlated ( r > 0.96 for four different comparisons). Our simple micrometeorological measurements are suitable predictors of T es for mule deer and cattle in winter.
MBRS measurements of overlayer effects on surface lifetimes and reaction probabilities

The interaction of formic acid with Ni(110), Ni(110)-carbide, Ni(110)-graphite, and Ni(110)-sulfide surfaces was examined by molecular beam relaxation spectrometry. The apparent first-order rate constants for the desorption of formic acid (Ts < 300 °K) were remarkably similar on all of the surfaces studied, suggesting that the low-temperature formic acid adsorption/desorption interactions were essentially identical on the different catalytic surfaces investigated. The onset of formic acid decomposition occurred in the vicinity of room temperature for the different surfaces examined, and the decomposition probabilities above room temperature varied appreciably from surface to surface. The decomposition probabilities above room temperature were 0.9 for Ni(110), 0.5 for Ni(110)-carbide, and < 0.1 for Ni(110)-graphite and Ni(110)-sulfide.
Positional behavior, selective use of habitat substrate and associated non-positional behavior in free-rangingColobus guereza (Rüppel, 1835)

Positional behavior (posture and locomotion), associated social/maintenance behaviors and selective utilization of available habitat structure were recorded for free-rangingColobus guereza occupying a remant montane forest near Limuru, Kenya. This research design focuses on relationships between anatomy, behavior, and the environment and provides a framework for interpreting adaptations inColobus. Quantitative analyses show daily activity patterns. These monkeys spend most of their time in above branch postural activities, primarily in sitting postures. Locomotion accounts for less than one-fifth of positional behavior. In both postural and locomotor sequences, the forelimbs may be placed above the shoulder complex, often in abducted positions. Suspensory positional behavior is rare. Most activity occurs within Zone II, flexible branches of medium diameter and less than 45° in grade. Selective use of the substrate and preferred positional modes are related to variables such as social/maintenance activities, weight distribution of the link system and substrate configuration. These data suggest that, (a) black and white colobus do not exhibit behavior associated with so-called “semibrachiation” and (b) bio-behavioral adaptations involving foraging and feeding strategies may account, in part, for observed morphological differences among Old World monkeys.
The Case for Continuing Education in Veterinary Colleges

Many resources are available from other domains that are relevant to veterinary education. "Currents in Education," edited by Katherine M. Edmondson, is intended to present thought-provoking information about teaching and learning from sources outside the veterinary field. This regular feature of JVME will highlight relevant educational research published elsewhere, and provide a brief synopsis and analysis of the work and its implications for veterinary education. Submissions are welcome.
Designing to support critical engagement with statistics

The purpose of this paper is to describe a trajectory of designing for particular forms of engagement with mathematics. The forms of engagement that were targeted through these design experiments involved making intentional choices about which procedures to leverage in order to support particular claims (what I call critical engagement). In particular, this paper presents two rounds of a design cycle of a statistics unit, created in the context of an online, interactive videogame called Quest Atlantis. Examining the design history of the unit, this paper demonstrates how iterative refinements of the unit supported increasing critical engagement with the content, and specifically, the importance of fostering both intentionality and experiences of consequentiality in the designs. Finally, the paper considers the implications of the lessons learned for this targeted intervention for our understanding of how elements of design support students’ mathematical reasoning more generally.
Selective Uncoupling of RGS Action by a Single Point Mutation in the G Protein α-Subunit

Heterotrimeric G proteins function as molecular relays, shuttling between cell surface receptors and intracellular effectors that propagate a signal. G protein signaling is governed by the rates of GTP binding (catalyzed by the receptor) and GTP hydrolysis. RGS proteins (regulators of G protein signaling) were identified as potent negative regulators of G protein signaling pathways in simple eukaryotes and are now known to act as GTPase-activating proteins (GAPs) for G protein α-subunits in vitro. It is not known, however, if Gα GAP activity is responsible for the regulatory action of RGS proteins in vivo. We describe here a Gα mutant in yeast (gpa1 sst) that phenotypically mimics the loss of its cognate RGS protein (SST2). The gpa1 sst mutant is resistant to an activated allele of SST2 in vivo and is unresponsive to RGS GAP activityin vitro. The analogous mutation in a mammalian Gqα is also resistant to RGS action in transfected cells. These mutants demonstrate that RGS proteins act through Gα and that RGS-GAP activity is responsible for their desensitizing activity in cells. The Gαsst mutant will be useful for uncoupling RGS-mediated regulation from other modes of signal regulation in whole cells and animals.
Bigger is Not Always Better for Overwintering Young-of-Year Steelhead

Abstract Many fishes occur across broad ranges of latitude and elevation, where winter temperatures can vary from mild to harsh. We conducted a laboratory experiment with three sizes of age-0 steelhead Oncorhynchus mykiss to examine growth, condition, and energy reserves under low rations at three levels of water temperature typical of this species' distribution during winter. At the end of the 111-d experiment, all three starting sizes of age-0 steelhead (small, 2–3 g; medium, 3–4 g; large, 4–5 g) held in 3°C water had lower total lipid weight than those held in 6°C and 9°C water. Large fish had higher total lipid weight than small fish at the onset of the experiment and retained higher amounts at the end. However, large fish had either the lowest percentage increases or the highest percentage decreases in fork length, biomass, condition factor, total lipid weight, and percent lipids within all thermal treatments. The magnitude of the differences between small and large fish was highest in the warmest (9...
Ubl4b, an X-derived retrogene, is specifically expressed in post-meiotic germ cells in mammals

Post-translational modification by ubiquitin and ubiquitin-related proteins plays critical roles in protein degradation and in regulation of essential cellular processes. In mammals, transcription grinds to a halt during late spermiogenesis due to compaction of the spermatid genome, which creates a special need for robust post-transcriptional regulation. Here, we report the finding of a novel mouse ubiquitin-like protein, UBL4B. Ubl4b is a testis-specific autosomal gene. Ubl4b lacks introns and evidently arose from an X-linked intron-bearing housekeeping gene, Ubl4a, by retroposition during mammalian evolution. While Ubl4a is expressed throughout spermatogenesis, Ubl4b is restricted to post-meiotic germ cells. Ubl4a is highly conserved, but Ubl4b has undergone rapid evolution and may have evolved new functions. Our data suggest that evolution of Ubl4b is not due to meiotic sex chromosome inactivation (MSCI). Alternatively, origination of Ubl4b was due to MSCI, but Ubl4b eventually evolved to be restricted to post-meiotic germ cells.
Interaction energies between β-lactam antibiotics and E. coli penicillin-binding protein 5 by reversible thermal denaturation

Penicillin-binding proteins (PBPs) catalyze the final stages of bacterial cell wall biosynthesis. PBPs form stable covalent complexes with β-lactam antibiotics, leading to PBP inactivation and ultimately cell death. To understand more clearly how PBPs recognize β-lactam antibiotics, it is important to know their energies of interaction. Because β-lactam antibiotics bind covalently to PBPs, these energies are difficult to measure through binding equilibria. However, the noncovalent interaction energies between β-lactam antibiotics and a PBP can be determined through reversible denaturation of enzyme–antibiotic complexes. Escherichia coli PBP 5, a d-alanine carboxypeptidase, was reversibly denatured by temperature in an apparently two-state manner with a temperature of melting (Tm) of 48.5°C and a van't Hoff enthalpy of unfolding (ΔHVH) of 193 kcal/mole. The binding of the β-lactam antibiotics cefoxitin, cloxacillin, moxalactam, and imipenem all stabilized the enzyme significantly, with ΔTm values as high as +4.6°C (a noncovalent interaction energy of +2.7 kcal/mole). Interestingly, the noncovalent interaction energies of these ligands did not correlate with their second-order acylation rate constants (k2/K′). These rate constants indicate the potency of a covalent inhibitor, but they appear to have little to do with interactions within covalent complexes, which is the state of the enzyme often used for structure-based inhibitor design.
Beyond the ENCODE project: using genomics and epigenomics strategies to study enhancer evolution

The complex expression patterns observed for many genes are often regulated by distal transcription enhancers. Changes in the nucleotide sequences of enhancers may therefore lead to changes in gene expression, representing a central mechanism by which organisms evolve. With the development of the experimental technique of chromatin immunoprecipitation (ChIP), in which discrete regions of the genome bound by specific proteins can be identified, it is now possible to identify transcription factor binding events (putative cis-regulatory elements) in entire genomes. Comparing protein-DNA binding maps allows us, for the first time, to attempt to identify regulatory differences and infer global patterns of change in gene expression across species. Here, we review studies that used genome-wide ChIP to study the evolution of enhancers. The trend is one of high divergence of cis-regulatory elements between species, possibly compensated by extensive creation and loss of regulatory elements and rewiring of their target genes. We speculate on the meaning of the differences observed and discuss that although ChIP experiments identify the biochemical event of protein-DNA interaction, it cannot determine whether the event results in a biological function, and therefore more studies are required to establish the effect of divergence of binding events on species-specific gene expression.
Maximizing Benefits for Effective Cancer Survivorship Programming: Defining a Dissemination and Implementation Plan

Although calls for improvements in cancer survivorship planning and programming exist, implementation has lagged. As with most guidelines, moving from recommendations to implementation requires active planning and systems changes to insure sustained use. Here, we draw on the latest in implementation science to outline a process that cancer organizations can use in designing, implementing, prioritizing, and evaluating cancer survivor programs to improve patient outcomes, using smoking cessation as a primary example. We consider the scientific evidence for benefit from interventions and the strategy for implementation and evaluation to sustain programs. The Oncologist 2011;16:1189–1196
Low-Density, Refractory Multi-Principal Element Alloys of the Cr-Nb-Ti-V-Zr System: Microstructure and Phase Analysis (Postprint)

Abstract The crystal structure, microstructure, density and Vickers hardness of four multi-principal element alloys, NbTiVZr, NbTiV 2 Zr, CrNbTiZr, and CrNbTiVZr, are reported. The characteristics of these potential new high-temperature structural alloys are explored. The alloys were prepared by vacuum arc melting followed by hot isostatic pressing (at 1200 °C, 207 MPa for 1 h) and homogenization annealing (at 1200 °C for 24 h). The alloys have densities of 6.52, 6.34, 6.67 and 6.57 g cm −3 , and Vickers microhardness values of 3.29, 2.99, 4.10 and 4.72 GPa, respectively. The NbTiVZr alloy is essentially a single-phase alloy consisting of a coarse-grained disordered body-centered cubic (bcc) phase with fine, submicron-size precipitates inside the grains. The NbTiV 2 Zr alloy contains three disordered bcc phases. The CrNbTiZr and CrNbTiVZr alloys contain a disordered bcc phase and an ordered Laves phase. The lattice parameters and compositions of the identified phases are reported. The experimental data are compared with the results of the thermodynamic modeling of non-equilibrium and equilibrium phases in these alloys.
Haemodynamic flow: Symmetry and synthesis

This paper is presented as a summary and synthesis of the presentations at the conference entitled "Breaking Symmetry in Haemodynamics". As the accompanying papers will attest, there has been enormous progress in understanding the effects of fluid flow on the arterial endothelium and the consequential effects on the vessel wall. It is now clearly understood that the focal lesions found in atherosclerotic arteries are the product of asymmetrical flow and the resulting disturbed flow that occurs near arterial bifurcations and other selected points around the human vasculature. The flow in large vessels can now be determined accurately with MR and in vitro cast models. Although theory allows arterial flow to be characterized by asymmetry in time and space, our understanding of the processes that act to translate this asymmetry into pathology is becoming much more symmetric, or complete. The new frontiers of research in arterial flow are now translating to smaller scales, at the cellular level and below.
Seiberg-Witten invariants and double covers of 4-manifolds

We establish explicit formulas for Seiberg-Witten invariants of (possibly ramified) double covers of smooth 4-manifolds. partially supported by an NSF grant and a Sloan fellowship partially supported by SRF and Research Board grant of University of Missouri 2 Seiberg-Witten invariants and double cover
INTERLEUKIN 1 PRODUCTION DURING ACCESSORY CELL-DEPENDENT MITOGENESIS OF T LYMPHOCYTES

We have studied the control and significance of IL-1 production in human leukocyte cultures during accessory cell-dependent, T lymphocyte mitogenesis using sensitive bioassays and immunolabeling techniques. In primary antigen-dependent systems like the MLR, IL-1 production was not detected in accessory cells (monocytes, dendritic cells) or T cells, suggesting that it is not an early product in these responses. However, monocytes could be induced to make IL-1 after interacting with sensitized antigen-specific T cells. Both alloreactive T cell clones or freshly prepared lymphoblasts induced IL-1 provided the monocytes carried the HLA-DR antigens to which the T cells were initially sensitized. Even in these circumstances, dendritic cells and B cells failed to make IL-1. The mechanism whereby activated T cells induce IL-1 in monocytes was explored. Supernatants from cocultures of monocytes and T cells or several recombinant cytokines induced little or no IL-1. A more potent antigen independent pathway of IL-1 induction was identified. IL-1 could be induced in third-party HLA-DR nonspecific monocytes in cocultures of alloreactive T cell clones or blasts and HLA-DR-specific dendritic cells. The induction was factor independent since dendritic cells and T blasts placed in a chamber separate from third-party monocytes by a semipermeable membrane did not induce monocyte IL-1. These results suggest that a cell contact mechanism rather than an IL-1-inducing factor leads to IL-1 production. The role of IL-1 in T cell proliferation was tested with a polyclonal anti-IL-1 antibody. The antibody failed to block the proliferation of primary T cells, or alloreactive T cell clones and blasts stimulated with HLA-specific monocytes or dendritic cells, even though IL-1 in the medium was neutralized.
Simultaneous intraspecific facilitation and interspecific competition between native and annual grasses

Invasive annual grasses tend to construct thinner and less dense root and leaf tissue than native perennial grasses. This allows invasive annuals to grow faster and produce more biomass in the arid grasslands of the United States. Based on these differences we tested the hypotheses that: 1) Competitive effects of the native perennial on the invasive annual will increase as plant developmental stage increases and as drought stress increases. 2) Drought stress will reduce the competitive effect of invasive annuals on native perennials proportionately more than drought stress reduces the competitive effect of native perennials on the invasive annual. 3) Facilitation among native perennial grass seedlings will decrease as developmental stage increases. Competitive effects of native squirreltail, on invasive medusahead, increased as the initial developmental stage of squirreltail increased, but not vice versa. Drought stress reduced the competitive effect of medusahead on squirreltail target biomass more than drought stress reduced the competitive effect of squirreltail on medusahead target biomass. While both squirreltail and medusahead displayed intraspecific facilitation, the net effect of their interspecific interaction was negative for both species. Habitat amelioration manifests itself differently depending on species traits, and can create conditions that simultaneously benefit one species while hindering another.
Rational Design Leads to More Potent RNA Interference Against Hepatitis B Virus: Factors Effecting Silencing Efficiency

RNA interference (RNAi) can be an effective antiviral agent; however, overexpression of RNAi can be toxic through competition with the endogenous microRNA (miRNA) machinery. We used rational design to identify highly potent RNAi that is effective at nontoxic doses. A statistical analysis was conducted to pinpoint thermodynamic characteristics correlated with activity. Sequences were selected that conformed to a consensus internal stability profile (ISP) associated with active RNAi, and RNAi triggers were expressed in the context of an endogenous miRNA. These approaches yielded highly active hepatitis B virus (HBV) RNAi. A statistical analysis found a correlation between activity and nucleation by binding within the seed sequence to accessible regions in the target RNA. Guide strands were selected for favorable strand biasing, but increased strand biasing did not correlate with potency, suggesting a threshold effect. Exogenous short hairpin RNAs (shRNAs), but not miRNAs were previously reported to compete with miRNAs for the miRNA/RNAi machinery. In contrast, we show that exogenous Polymerase III- but not Polymerase II-driven miRNAs compete with exogenous miRNAs, at multiple steps in the miRNA pathway. Exogenous miRNAs also compete with endogenous miR-21. Thus, competition with endogenous miRNAs should be monitored even when using miRNA-based therapeutics. However, potent silencing was achieved at doses where competition was not observed.
The nature of the transport ATPase-digitalis complex. II. Some species differences and ouabain "exchange" characteristics.

Abstract [ 3 H]ouabain, bound to Na + , K + -ATPase in the presence of ATP, Mg 2+ + Na + ( complex I ) or in the prescence of Mg 2+ + inorganic phosphate ( complex II ), was more stable when beef heart rather than rabbit heart was the enzyme source. For both species, complex II was more stable than complex I . Unlabeled ouabain in the wash-off medium did not affect drug dissociation kinetics, but did cause inhibition of enzyme activity, suggesting ouabain exchange.
Modeling the influence of task on attention

We propose a computational model for the task-specific guidance of visual attention in real-world scenes. Our model emphasizes four aspects that are important in biological vision: determining task-relevance of an entity, biasing attention for the low-level visual features of desired targets, recognizing these targets using the same low-level features, and incrementally building a visual map of task-relevance at every scene location. Given a task definition in the form of keywords, the model first determines and stores the task-relevant entities in working memory, using prior knowledge stored in long-term memory. It attempts to detect the most relevant entity by biasing its visual attention system with the entity's learned low-level features. It attends to the most salient location in the scene, and attempts to recognize the attended object through hierarchical matching against object representations stored in long-term memory. It updates its working memory with the task-relevance of the recognized entity and updates a topographic task-relevance map with the location and relevance of the recognized entity. The model is tested on three types of tasks: single-target detection in 343 natural and synthetic images, where biasing for the target accelerates target detection over twofold on average; sequential multiple-target detection in 28 natural images, where biasing, recognition, working memory and long term memory contribute to rapidly finding all targets; and learning a map of likely locations of cars from a video clip filmed while driving on a highway. The model's performance on search for single features and feature conjunctions is consistent with existing psychophysical data. These results of our biologically-motivated architecture suggest that the model may provide a reasonable approximation to many brain processes involved in complex task-driven visual behaviors.
Low cost test bed tool development for validation of mission critical events

The Cassini Program is one of the last large interplanetary spacecraft missions. It is a joint effort between the European Space Agency, the Italian Space Agency and NASA. The U.S. portion of the mission is managed for NASA by the Jet Propulsion Laboratory (JPL). The primary mission is to survey the complex Saturnian system and release the ESA-Huygens probe at Titan. The success of the Cassini Mission has been largely due to its many simulation test beds and its rigorous test program. The Integrated Test Laboratory (ITL) at the JPL is an integral part of the Cassini Program and provides "hardware in the loop simulation". Pre-launch, the ITL's primary role was to validate system level architecture, subsystem flight software, ground software, and support equipment simulation software. Its present role has increasingly focused on mission operations sequence testing, anomaly investigation, training and validation of mission milestones. This expanded role has led to the development of necessary analysis tools. These tools were developed quickly and at low cost given that their necessity was not foreseen during early mission planning. Several rapid development techniques and cost cutting methods were used to implement the needed tools. The methods involved were; use of freeware, use of commercial off the shelf (COTS) software, and technology transfer with other Projects at JPL.
The Markov-Dubins problem with angular acceleration control

We study a modified version of the well known Markov-Dubins problem, in which the control is angular acceleration rather than angular velocity. We show that an optimal trajectory cannot contain a junction of a bang-bang and a singular piece, and use the results of Zelikin and Borisov (1994) to show that there are Pontryagin extremals involving infinite chattering.
Surface Density Optimization of V-Zr Mixed Oxides Cografted on γ-Al2O3 Using OV(O i Pr)3 and Zr(O n Bu)4 Precursors

Cografted catalysts are synthesized by reacting surface -OH groups of a catalyst support with a solution containing two or more metal precursors. Under these circumstances factors such as temperature, concentration of metal precursors, time of cografting, and variations in metal precursor feeds can affect the surface metal densities. To understand influence of these parameters a compositional range of V-Zr cografted catalysts were synthesized using OV(O i Pr)3 and Zr(O n Bu)4 and studied. These catalysts were then characterized using ICP-OES, XRD, and XPS. XRD revealed that cografting was amorphous and XPS studies indicated that V5+ and Zr4+ were the only species present under ambient conditions.
Serologic Response of Roosters to Gradient Dosage Levels of a Commercially Available Live F Strain-Derived Mycoplasma gallisepticum Vaccine Over Time

SUMMARY. Spray application is a commonly used, time- and labor-efficient means to deliver live Mycoplasma gallisepticum (MG) vaccine to laying hens in commercial production facilities. The dosage of vaccine received by spray-vaccinated birds can vary due to variation in the spray plume and the vaccine suspension droplet trajectory. In this study, a total of 48 Hy-Line W-36 males were placed individually in isolation units following eye-drop application of gradient levels (1×, 10−1×, 10−2×, 10−3×, 10−4×, 10−5×, 10−6×, and unvaccinated control) of the MG vaccine. The determined titer associated with a 1× dose was 2 × 106 colony-forming units/dose. Serologic response was assessed weekly following vaccination via serum plate agglutination (SPA) for weeks one through seven postvaccination (p.v.). In addition, immunologic response was assessed at 5, 6, and 7 wk p.v. via MG enzyme-linked immunosorbent assay (ELISA). As indicated by SPA analyses, a 1× dose of vaccine resulted in 100% seroconversion, and dose leve...
Genetic Disorders of Cardiac Morphogenesis: The DiGeorge and Velocardiofacial Syndromes

Congenital heart defects are thought to result from a variety of genetic and environmental influences. Although most CHD occurs as a sporadic event, many defects are part of a well-defined genetic syndrome. Particular types of CHD are often overrepresented in the context of a syndrome compared with the general population. Identification of the genetic etiology of the syndrome may lend insight into the etiology of the associated cardiac malformation. Thus, because conotruncal cardiac defects are a cardinal feature of DGS, the specific genetic etiology of this syndrome has become of great interest to the cardiologist and cardiac developmental biologist. Although the phenotype is highly variable, DGS is typically characterized by aplasia or hypoplasia of the thymus, aplasia or hypoplasia of the parathyroid glands, conotruncal cardiac defects, and mildly dysmorphic facial features.1 2 The most common cardiac defects include truncus arteriosus, interrupted aortic arch, and tetralogy of Fallot.3 Defects in multiple organ systems, which arise concurrently and from common precursors during embryogenesis, have led to the proposal that DGS is a developmental field defect.4 A developmental field refers to a population of embryonic cells that behave as a single coordinated developmental unit. Disruption of this “morphogenetically reactive unit” results in a particular phenotype, which may involve many different end organs and may be phenotypically variable depending upon the timing and nature of the perturbation. Different factors, such as genetic alterations or environmental insults, could disrupt the normal morphogenesis of the reactive unit and result in a similar phenotype. Preliminary evidence suggests that in the case of DGS, the morphogenetically reactive unit is the cephalic and cranial neural crest. Experiments in the chicken and rodent have demonstrated that neural crest cells from the preotic and postotic caudal hindbrain form the mesenchyme of the third and fourth arches/pouches. The third …
Spatial patterning of fuels and fire hazard across a central U.S. deciduous forest region

Information describing spatial and temporal variability of forest fuel conditions is essential to assessing overall fire hazard and risk. Limited information exists describing spatial characteristics of fuels in the eastern deciduous forest region, particularly in dry oak-dominated regions that historically burned relatively frequently. From an extensive fuels survey of unmanaged forest lands (1,446 plots) we described fuel loadings and spatial patterns of fine and coarse fuels. We attempted to explain the variability in fuel loading of each time-lag fuel class using landscape and seasonal variables through a multiple regression modeling approach. Size class distributions of woody fuels were generally homogeneous across the region except in the glaciated portions of Illinois where loadings appeared lower. Temporally, litter depths progressively decreased from leaffall (November). A fire hazard model that combined seasonal changes in litter depth and fuel moisture content depicted the degree of regional spatial variability during the transition between extreme dry and wet conditions. In the future, fire hazard indices could be paired with ignition probabilities in order to assess spatio-temporal variability of fire risk within the region.
Multiple Perspectives on Tobacco Use Among Youth With Mental Health Disorders and Addictions

Purpose. Youth and young adults with mental health disorders and addictions are at a high risk of becoming nicotine dependent, and at least half will die of tobacco-related diseases. In comparison to the general population, this population also faces neurobiological and psychosocial vulnerabilities. There is a critical need for community services and research targeting tobacco interventions for these individuals. Methods. A concurrent mixed methods study was conducted by collecting data from in-depth key informant interviews, focus groups, and a survey. Qualitative key informant interviews with healthcare professionals (n 5 11) and youth focus groups (n 5 32) were conducted by using semi-structured questioning regarding barriers and facilitators to tobacco interventions. Content analysis was used to code transcripts and categorize themes. Survey data were also collected from 230 smokers ages 13 to 17 years (n 5 62) and young adults ages 18 to 25 years (n 5 40) at three community mental health centers. The survey inquired about tobacco use, motivation to quit, history of quit attempts, and treatment preferences. Results. Five thematic categories were identified in both the adult key informant interviews and the focus groups with youth: (1) motivation to quit, (2) cessation treatment needs, (3) social influence, (4) barriers to treatment, and (5) tobacco-free policy. Among those surveyed, 44% currently smoked. Youth and young adult survey respondents who smoked were often motivated to quit, few had used proven tobacco cessation aids, but there was interest in access to nicotine replacement therapy. Conclusion. Merged qualitative and quantitative findings support past literature regarding youth in the general population but also expand upon our knowledge of issues specific to youth and young adults with mental health disorders and addictions. Findings suggest interventions warranting further attention in community treatment settings. (Am J Health Promot 2011;25[5 Supplement]:S31–S37.)
Role of female behavior in controlling population growth in mice

Sex ratio does not appear to be a factor in generating the characteristic population growth curve. Freely growing populations of house mice, consisting of all females and one male, stopped their growth at approximately the same densities as normal sexratio populations used as references. The mechanism(s) of female control of population dynamics may be related to female aggressive behavior. As the all-female/one-male populations approached their maximum size, the females began to show wounding patterns and social hierarchies in much the same manner as males in populations with normal sex ratios. The male in each of the populations was severely wounded in the posterior region, and each lost its tail as a result of injuries which could have been inflicted only by the females. The female social hierarchy can be seen only when there has been reproduction and population growth. Assembled populations of all females rarely exhibit aggressive behavior. Female aggression becomes apparent only when the population approaches its maximum size and thereafter. These data are consistent with the hypothesis that males are competitive among themselves for territory and social rank, and ultimately to mate with the females. Other investigators have indicated that females respond to population size, which may reflect increased competition between the females with the establishment of territories. Thus female agression may control population growth, a role previously ascribed to male aggression.