cssi/SciSciGPT-SciSciNet huggingface dataset:
Dietary Soluble and Insoluble Fiber With or Without Enzymes Altered the Intestinal Microbiota in Weaned Pigs Challenged With Enterotoxigenic E. coli F18

Post-weaning diarrhea caused by enterotoxigenic E. coli (ETEC) causes significant economic losses for pig producers. This study was to test the hypotheses that an ETEC challenge disrupts intestinal microbial homeostasis and the inclusion of dietary soluble (10% sugar beet pulp) or insoluble fiber (15% corn distillers dried grains with solubles) with or without exogenous carbohydrases will protect or restore the gut microbial homeostasis in weaned pigs. Sixty crossbred piglets (6.9 ± 0.1 kg) were blocked by body weight and randomly assigned to one of six treatments (n = 10), including a non-challenged control (NC), ETEC F18-challenged positive control (PC), ETEC-challenged soluble fiber without (SF-) or with carbohydrases (SF+), and ETEC-challenged insoluble fiber without (IF-) or with carbohydrases (IF+). Pigs were housed individually and orally received either ETEC inoculum or PBS-sham inoculum on day 7 post-weaning. Intestinal contents were collected on day 14 or 15. The V4 region of the bacterial 16S rRNA was amplified and sequenced. High-quality reads (total 6,671,739) were selected and clustered into 3,330 OTUs. No differences were observed in α-diversity among treatments. The ileal microbiota in NC and PC had modest separation in the weighted PCoA plot; the microbial structures were slightly altered by SF+ and IF- compared with PC. The PC increased ileal Escherichia-Shigella (P < 0.01) and numerically decreased Lactobacillus compared to NC. Predicted functional pathways enriched in the ileal microbiota of PC pigs indicated enhanced activity of Gram-negative bacteria, in agreement with increased Escherichia-Shigella. The SF+ tended to decrease (P < 0.10) ileal Escherichia-Shigella compared to PC. Greater abundance of ileal Streptococcus, Turicibacter, and Roseburia and colonic Prevotella were observed in SF- and SF+ than PC (P < 0.05). Pigs fed IF + had greater Lactobacillus and Roseburia than PC pigs (P < 0.05). The ETEC challenge reduced total volatile fatty acid (VFA) compared with NC (P < 0.05). The SF+ tended to increase (P < 0.10) and SF- significantly increased (P < 0.05) colonic total VFA compared with PC. Collectively, ETEC challenge disrupted gut microbial homeostasis and impaired microbial fermentation capacity. Soluble fiber improved VFA production. Dietary fiber and carbohydrases altered microbiota composition to maintain or restore microbial homeostasis.
Decomposition of integrated scheduling and dynamic optimization problems using community detection

Abstract In this paper the decomposition of the integrated cyclic scheduling and dynamic optimization problem is analyzed using community detection. Different production systems are examined and based on the results of the community detection and the centrality of the constraint unipartite graph, a two level hierarchical structure is identified, with the scheduling problem in the first level and the dynamic optimization subproblems in the second level. The variables that link the two levels are continuous and obtained from the results of the community detection. Finally, Generalized Benders Decomposition is applied on the decomposed optimization problem obtained from the community detection and a solution is obtained faster than solving the problem monolithically.
Changes in Lumbo-Pelvic Coordination of Individuals With and Without Low Back Pain When Wearing a Hip Orthosis.

Individuals with low back pain demonstrate an abnormal lumbo-pelvic coordination compared to back-healthy individuals. This abnormal coordination presents itself as a reduction in lumbar contributions and an increase in pelvic rotations during a trunk forward bending and backward return task. This study investigated the ability of a hip orthosis in correcting such an abnormal lumbo-pelvic coordination by restricting pelvic rotation and, hence increasing lumbar contributions. The effects of the hip orthosis on the lumbo-pelvic coordination were investigated in 20 low back pain patients and 20 asymptomatic controls. The orthosis reduced pelvic rotation by 12.7° and increased lumbar contributions by 11%. Contrary to our expectation, orthosis-induced changes in lumbo-pelvic coordination were smaller in patients; most likely because our relatively young patient group had smaller unrestricted pelvic rotations compared to asymptomatic individuals. Considering the observed capability of a hip orthosis in causing the expected changes in lumbo-pelvic coordination when there is a relatively large pelvic contribution to trunk motion, application of a hip orthosis may provide a promising method of correcting abnormal lumbo-pelvic coordination, particularly among patients who demonstrate larger pelvic rotation, that warrants further investigation.
Dissection of quantitative trait loci for root characters and day length sensitivity in SynOpDH wheat (Triticum aestivum L.) bi-parental mapping population

The genetics of the root system is still not dissected for wheat and lack of knowledge prohibits the use of marker-assisted selection in breeding. To understand the genetic mechanism of root development, Synthetic W7984 × Opata M85 doubled-haploid (SynOpDH) mapping population was evaluated for root and shoot characteristics in PVC tubes until maturity. Two major quantitative trait loci (QTLs) for total root biomass were detected on homoeologous chromosomes 2A and 2D with logarithm of the odds scores between 6.25–10.9 and 11.8–20.86, and total phenotypic effects between 12.7–17.7 and 26.6–40.04% in 2013 and 2014, respectively. There was a strong correlation between days to anthesis and root and shoot biomass accumulation (0.50–0.81). The QTL for biomass traits on chromosome 2D co-locates with QTL for days to anthesis. The effect of extended vegetative growth, caused by photoperiod sensitivity (Ppd) genes, on biomass accumulation was always hypothesized, this is the first study to genetically support this theory.
A Semi-Automated System for Exploring and Fixing OSM Connectivity

As an open license project, Open Street Map (OSM) aims to make the collectively produced geographic data freely available to be used for various purposes. Routing engines frequently take advantage of this data set. Nonetheless, providing routing services on top of OSM requires the full connectivity of the OSM road network graph in the interest area. This connectivity needs to be achieved individually at every level of the road network graph: the motorway, trunk, primary, secondary, tertiary, and residential roads. However, due to its open-editing nature, the OSM data often contains faults attributed to issues like missing road network connections or mistakenly attributed road segments. In this paper, we demonstrate a system we have developed that helps the end-user (i.e., cartographer) discover and fix the connectivity errors in an OSM road network graph. More specifically, the system aims to achieve full connectivity in the overall road network graph, which in turn requires full connectivity at each road level. The system automatically detects the connectivity errors that would otherwise remain undetected or need a lengthy manual process to discover. It can accept hints from the editor through its easy to use graphical user interface to investigate errors further, improve the detection process, and subsequently fix them. Based on our pilot runs in New Zealand with the supervision of professional cartographers and a team from Microsoft Geospatial, we were able to detect more than 300 incorrect connections and to achieve connectivity across different road levels.
Semantic Annotation for Tabular Data.

Detecting semantic concept of columns in tabular data is of particular interest to many applications ranging from data integration, cleaning, search to feature engineering and model building in machine learning. Recently, several works have proposed supervised learning-based or heuristic pattern-based approaches to semantic type annotation. Both have shortcomings that prevent them from generalizing over a large number of concepts or examples. Many neural network based methods also present scalability issues. Additionally, none of the known methods works well for numerical data. We propose $C^2$, a column to concept mapper that is based on a maximum likelihood estimation approach through ensembles. It is able to effectively utilize vast amounts of, albeit somewhat noisy, openly available table corpora in addition to two popular knowledge graphs to perform effective and efficient concept prediction for structured data. We demonstrate the effectiveness of $C^2$ over available techniques on 9 datasets, the most comprehensive comparison on this topic so far.
Characterization and treatment of Bakken oilfield produced water as a potential source of value-added elements.

Abstract The oilfield produced water is a major waste stream in places where shale-gas production is growing rapidly. The reuse of produced water merits consideration because this practice helps reduce freshwater demand for fracking and moderates water pollution. Knowledge about the chemistry of produced water is needed to develop sustainable treatment/reuse strategies and set standards for acceptable levels of treatment of produced water. Thus, the author performed the first comprehensive analysis of oilfield produced water collected from the Bakken shale play in the U.S. state of North Dakota that represents the nation's third-largest net increase in proven crude oil reserves. The concentrations of a total of 36 elements in 13 IUPAC groups were determined. Among them, a few metals that are critical to the economy of the United States were detected at elevated concentrations (median, mg/L): K (7,620), Mg (2780), Sr (1610), Li (69), and Mn (33). Heavy metals essential for plants and animals, including Cu, Zn, and Mn, were detected at ppm levels. Measurable concentrations of highly toxic metal ions such as Cd and Pb were not detected. Concentrations of rare earth elements and platinum group metals were below respective detection limits. The produced water samples had very high total dissolved solids (237,680 ± 73,828 mg/L) and total hardness (>31,000 mg/L as CaCO3) but an extremely low alkalinity (152.4 ± 184.9 mg/L as CaCO3); therefore, softening by lime and soda was ineffective. Softening by caustic soda removed 99.5% hardness ions (Ca and Mg) under alkaline conditions. This study provides vital insight into the chemistry and treatability of produced water containing various metals.
Association of glycemia with insulin sensitivity and β-cell function in adults with early type 2 diabetes on metformin alone

Abstract Aims Evaluate the relationship between measures of glycemia with β-cell function and insulin sensitivity in adults with early type 2 diabetes mellitus (T2DM). Methods This cross-sectional analysis evaluated baseline data from 3108 adults with T2DM A Comparative Effectiveness (GRADE) Study. Insulin and C-peptide responses and insulin sensitivity were calculated from 2-h oral glucose tolerance tests. Regression models evaluated the relationships between glycemic measures (HbA1c, fasting and 2-h glucose), measures of β-cell function and insulin sensitivity. Results Insulin and C-peptide responses were inversely associated with insulin sensitivity. Glycemic measures were inversely associated with insulin and C-peptide responses adjusted for insulin sensitivity. HbA1c demonstrated modest associations with β-cell function (range: r − 0.22 to −0.35). Fasting and 2-h glucose were associated with early insulin and C-peptide responses (range: r − 0.37 to −0.40) as well as late insulin and total insulin and C-peptide responses (range: r − 0.50 to −0.60). Conclusion Glycemia is strongly associated with β-cell dysfunction in adults with early T2DM treated with metformin alone. Efforts to improve glycemia should focus on interventions aimed at improving β-cell function. This Trial is registered in Clinicaltrials.gov as NCT01794143 .
The N-terminal domain of the A12.2 subunit stimulates RNA polymerase I transcription elongation

Abstract Eukaryotes express three DNA-dependent RNA polymerases (Pols) that are responsible for the entirety of cellular genomic expression. The three Pols have evolved to express specific cohorts of RNAs and thus have diverged both structurally and functionally to efficiently execute their specific transcriptional roles. One example of this divergence is Pol I’s inclusion of a proofreading factor as a bona fide subunit, as opposed to Pol II, which recruits a transcription factor, TFIIS, for proofreading. The A12.2 (A12) subunit of Pol I shares homology with both the Rpb9 subunit of Pol II as well as the transcription factor TFIIS, which promotes RNA cleavage and proofreading by Pol II. In this study, the functional contribution of the TFIIS-like C-terminal domain and the Rpb9-like N-terminal domain of the A12 subunit are probed through mutational analysis. We found that a Pol I mutant lacking the C-terminal domain of the A12 subunit (ΔA12CTD Pol I) is slightly faster than wild-type Pol I in single-nucleotide addition, but ΔA12CTD Pol I lacks RNA cleavage activity. ΔA12CTD Pol I is likewise similar to wild-type Pol I in elongation complex stability, whereas removal of the entire A12 subunit (ΔA12 Pol I) was previously demonstrated to stabilize transcription elongation complexes. Furthermore, the ΔA12CTD Pol I is sensitive to downstream sequence context, as ΔA12CTD Pol I exposed to AT-rich downstream DNA is more arrest prone than ΔA12 Pol I. These data demonstrate that the N-terminal domain of A12 does not stimulate Pol I intrinsic RNA cleavage activity, but rather contributes to core transcription elongation properties of Pol I.
Examining the Relationship Between Racialized Poverty Segregation and Hazardous Industrial Facilities in the U.S. Over Time

Scholars interested in understanding the unequal exposure to environmental harms by race and class have often relied on urban sociological theory. Specifically, the argument that the outmigration o...
Virus-associated disruption of mucosal epithelial tight junctions and its role in viral transmission and spread

Oropharyngeal, airway, intestinal, and genital mucosal epithelia are the main portals of entry for the majority of human pathogenic viruses. To initiate systemic infection, viruses must first be transmitted across the mucosal epithelium and then spread across the body. However, mucosal epithelia have well-developed tight junctions, which have a strong barrier function that plays a critical role in preventing the spread and dissemination of viral pathogens. Viruses can overcome these barriers by disrupting the tight junctions of mucosal epithelia, which facilitate paracellular viral penetration and initiate systemic disease. Disruption of tight and adherens junctions may also release the sequestered viral receptors within the junctional areas, and liberation of hidden receptors may facilitate viral infection of mucosal epithelia. This review focuses on possible molecular mechanisms of virus-associated disruption of mucosal epithelial junctions and its role in transmucosal viral transmission and spread.
Tunable Chemical Disorder in Concentrated Alloys: Defect Physics and Radiation Performance

The development of advanced structural alloys with performance meeting the requirements of extreme environments in nuclear reactors has been long pursued. In the long history of alloy development, the search for metallic alloys with improved radiation tolerance or increased structural strength has relied on either incorporating alloying elements at low concentrations to synthesize so-called dilute alloys or incorporating nanoscale features to mitigate defects. In contrast to traditional approaches, recent success in synthesizing multicomponent concentrated solid-solution alloys (CSAs), including medium-entropy and high-entropy alloys, has vastly expanded the compositional space for new alloy discovery. Their wide variety of elemental diversity enables tunable chemical disorder and sets CSAs apart from traditional dilute alloys. The tunable electronic structure critically lowers the effectiveness of energy dissipation via the electronic subsystem. The tunable chemical complexity also modifies the scattering mechanisms in the atomic subsystem that control energy transport through phonons. The level of chemical disorder depends substantively on the specific alloying elements, rather than the number of alloying elements, as the disorder does not monotonically increase with a higher number of alloying elements. To go beyond our knowledge based on conventional alloys and take advantage of property enhancement by tuning chemical disorder, this review highlights synergistic effects involving valence electrons and atomic-level and nanoscale inhomogeneity in CSAs composed of multiple transition metals. Understanding of the energy dissipation pathways, deformation tolerance, and structural stability of CSAs can proceed by exploiting the equilibrium and non-equilibrium defect processes at the electronic and atomic levels, with or without microstructural inhomogeneities at multiple length scales. Knowledge of tunable chemical disorder in CSAs may advance the understanding of the substantial modifications in element-specific alloy properties that effectively mitigate radiation damage and control a material's response in extreme environments, as well as overcome strength-ductility trade-offs and provide overarching design strategies for structural alloys.
Catalysis by Cobalt Carbonyls

Publisher Summary Transition metal carbonyls and their derivatives are remarkably effective and varied in their ability to catalyze reactions between unsaturated molecules. The carbonyl derivatives of cobalt are particularly active catalysts for such reactions and have been put to use in the industrial synthesis of higher aliphatic alcohols. The most important reason being that dicobalt octacarbonyl is a reasonably stable, commercially available, fairly well characterized compound which easily gives active catalytic intermediates. Most of the growth in our understanding of reactions catalyzed by dicobalt octacarbonyl has resulted from a study of the individual reactions of catalytic intermediates such as cobalt hydrocarbonyl. At much lower temperatures and pressures than are used in the corresponding catalytic processes, cobalt hydrocarbonyl has been found to give rise to similar reactions, but stoichiometrically. The carbon monoxide inhibition is most easily explained if the isomerization proceeds via the tricarbonyls rather than tetracarbonyls. An equally probable hypothesis is that under Oxo conditions the combination of temperature and carbon monoxide pressure result in the branched acylcobalt tricarbonyl for the first two olefins but a linear acylcobalt tetracarbonyl for ethyl acrylate.
Boundary Layer Problems in Applied Mechanics

Publisher Summary This chapter provides an introduction to boundary layer, presents a simple characterization of the boundary layer problem, and discusses varying detail of the analysis of several isolated problems, which fall into this category. The term “boundary layer” has become most closely associated with the phenomena arising when a fluid flows past an obstacle at high Reynolds number. There is a large and interesting variety of physical problems whose analysis is most appropriately carried out by invoking the ideas that are associated with boundary layer problems. The various boundary layer problems discussed are the ocean current problem, heat transfer problem, convection problem, and the relaxation oscillations of the van der Pol oscillator. Other problems discussed are elasticity problems and flow of a viscous fluid past an obstacle problem. The chapter also discusses the solution of the boundary layer problem that takes place in two steps. First, one finds an interior solution by integrating the system of equations, then one changes the scale of the normal coordinate to the boundary and the scale of any other functions whose size is not known in such a manner that a system of equations of the appropriate order is retained.
Aged-Related Changes in the Nails

A number of age-related changes to the nails can occur, without known association with medical disorders. Some nail changes can be associated with underlying medical disorders, enriched in older adults. Hence, recognition of specific nail changes and their potential associations can be clues to medical issues that should not be missed. Brittle nail syndrome, onychomycosis, and nail-associated malignancies are increased in older adults, and treatment requires special considerations in this population.
Combination of among and cardinality constraints

A cardinality constraint imposes that each value of a set V must be taken a certain number of times by a set of variables X, whereas an among constraint imposes that a certain number of variables of a set X must take a value in the set V. This paper studies several combinations of among constraints and several conjunctions of among constraints and cardinality constraints. Some filtering algorithms are proposed and they are characterized when it is possible. Moreover, a weak form of Singleton arc consistency is considered. At last, it is shown how the global sequencing constraint and the global minimum distance constraint can be easily modeled by some conjunctions of cardinality and among constraints. Some results are also given for the global minimum distance constraint. They show that our study outperforms the existing constraint in ILOG Solver.
A Zero-Sum Approach to Not-for-Profit Strategic Oversight: A practical, uncomplicated solution

Many not-for-profits lack an integrated budgeting process. Too often it is ad hoc, top down, and unrelated to an organization’s strategic mission. Despite improvements in the economy, the future remains uncertain, and competition for donor funding continues to increase. Organizations that are strategic and financially responsible will have a competitive edge with funders. Zero-Sum Budgeting is a decision-support tool which helps not-for-profits remain on budget without compromising their mission. It is a straightforward approach conceptually based on zero-sum game theory and flows organically from an organization’s strategic planning process. Using Zero-Sum Budgeting, a not-for-profit can deliver its most important commitments without having to overburden staff or make unplanned dips into cash reserves. At its core, this approach requires an organization to make strategic trade-offs when revenues fall short or unplanned actions occur that impact a pre-agreed cash position. This cash position is established at the start of the budget year and remains unchanged, acting as a fulcrum, which drives management action throughout the year. The article is written for senior not-for-profit executives who are in need of a fresh approach to strategic planning and budgeting. It provides a good overview of the process and benefits. It is jargon free, contains a step-by-step implementation guide as well as useful charts and templates that are professionally designed.
Scaling Analysis of Alloy Solidification and Fluid Flow in a Rectangular Cavity

A scaling analysis was performed to predict trends in alloy solidification in a side-cooled rectangular cavity. The governing equations for energy and momentum were scaled in order to determine the dependence of various aspects of solidification on the process parameters for a uniform initial temperature and an isothermal boundary condition. This work improved on previous analyses by adding considerations for the cooling bulk fluid flow. The analysis predicted the time required to extinguish the superheat, the maximum local solidification time, and the total solidification time. The results were compared to a numerical simulation for a Al-4.5 wt.% Cu alloy with various initial and boundary conditions. Good agreement was found between the simulation results and the trends predicted by the scaling analysis.
Trustworthy execution on mobile devices: what security properties can my mobile platform give me ?

We are now in the post-PC era, yet our mobile devices are insecure. We consider the different stake-holders in today's mobile device ecosystem, and analyze why widely-deployed hardware security primitives on mobile device platforms are inaccessible to application developers and end-users. We systematize existing proposals for leveraging such primitives, and show that they can indeed strengthen the security properties available to applications and users, all without reducing the properties currently enjoyed by OEMs and network carriers. We also highlight shortcomings of existing proposals and make recommendations for future research that may yield practical, deployable results.
Two-Tensor Tractography Using a Constrained Filter

We describe a technique to simultaneously estimate a weighted, positive-definite multi-tensor fiber model and perform tractography. Existing techniques estimate the local fiber orientation at each voxel independently so there is no running knowledge of confidence in the estimated fiber model. We formulate fiber tracking as recursive estimation: at each step of tracing the fiber, the current estimate is guided by the previous. To do this we model the signal as a weighted mixture of Gaussian tensors and perform tractography within a filter framework. Starting from a seed point, each fiber is traced to its termination using an unscented Kalman filter to simultaneously fit the local model and propagate in the most consistent direction. Further, we modify the Kalman filter to enforce model constraints, i.e. positive eigenvalues and convex weights. Despite the presence of noise and uncertainty, this provides a causal estimate of the local structure at each point along the fiber. Synthetic experiments demonstrate that this approach significantly improves the angular resolution at crossings and branchings while consistently estimating the mixture weights. In vivo experiments confirm the ability to trace out fibers in areas known to contain such crossing and branching while providing inherent path regularization.
Quantitative Mass Spectrometry Identifies Drug Targets in Cancer Stem Cell‐Containing Side Population

A multifaceted approach is presented as a general strategy to identify new drug targets in a breast cancer stem cell-containing side population. The approach we have utilized combines side population cell sorting and stable isotope labeling by amino acids in cell culture with mass spectrometry to compare and identify proteins with differential expression profiles between side population cells, know to be enriched in cancer stem cells, and nonside population cells, which are depleted in cancer stem cells, for two breast cancer cell lines, MCF7 and MDA-MB231. Almost 900 proteins were quantified, and several important proteins in cell cycle control and differentiation were found to be upregulated in the cancer stem cell-containing side population. Most interestingly, a splice isoform of pyruvate kinase M2 as well as peroxiredoxin 6 were found to be downregulated. The differential levels of three of these proteins, thymosin beta4 (TB4), proliferation-associated protein 2G4, and SIAH-interacting protein, were validated using Western blot. Furthermore, functional validation provided clear evidence that elevated TB4 expression contributes to drug resistance in the stem cell population. Small interfering RNA silencing of TB4 led to a loss of chemoresistance in two separate breast cancer populations. These proteins likely contribute to resistance in the cancer stem cell-containing side population, and their altered expression in a tumor causes clinical resistance to chemotherapy. The ability to perform quantitative mass spectrometry has enabled the identification of a series of proteins that could serve as future therapeutic targets.
Low-Temperature Mechanical Alloying Of Cu-Fe and Cu-Ta Powders

A model analysis is presented which explains ball-milling induced alloying in positive-heatof- mixing systems in terms of a dynamic balance between externally forced mixing and thermal phase decomposition mediated by deformation-enhanced population of defects. The possibility of eliminating the thermal decomposition to force single phase formation is examined by milling Cu-Fe and Cu-Ta powder mixtures at the liquid nitrogen temperature (LN2T). Over a range of compositions for Cu-Fe and almost the entire composition range for Cu-Ta, the two-phase region observed for room-temperature (RT) milling persisted after cryomilling. The moderate temperature dependence of milling-induced alloying is interpreted by analyzing the dynamics of the generation and annihilation of the nonequilibrium vacancies during deformation and impacts in a SPEX mill.
Auditory centers in the elasmobranch brain stem: Deoxyglucose autoradiography and evoked potential recording

Elasmobranchs are sensitive to low frequency sound, and electrophysiological studies have demonstrated acoustic responses from the ear. Five primary projections from the ear to the medulla have been found, but individually they could not be identified with either the auditory or the equilibrium modality since they originate in a mixed nerve. Metabolic mapping in the brain of the thornback guitarfish with [14C]2-deoxyglucose autoradiography and acoustic stimulation provided tentative identifications of acoustic centers in cell plate X of the medial octavolateralis nucleus, the anterior octaval nucleus, the nucleus of the lateral lemniscus, and the ventromedial division of the lateral mesencephalic nucleus. Evoked potential recordings confirmed acoustic activity in those sites and additionally in the reticular formation, and the lateral granule cell mass of the auricle. In tests in the mesencephalon the evoked potential disappeared within the range of elasmobranch behavioral thresholds and when the eighth nerves were cut, but was not changed when all 4 lateral line nerves were cut. The identified acoustic centers resemble those found in auditory lemniscal pathways in mammals and other tetrapods, but the most recent ancestor common to elasmobranchs and tetrapods lived 400 million years ago. Therefore, a basic auditory lemniscal pathway may be a longstanding feature of the vertebrate brain.
Fracture phenomenology of a lithium-aluminium-silicate glass-ceramic

Crack propagation mechanisms in a lithium-aluminium-silicate glass-ceramic have been studied as a function of both initial flaw size and temperature. Using controlled surface cracks, the fracture stress at room temperature was found to conform to the Griffith flaw size dependence. Extrapolation suggests that processing flaws of the order of 6 to 8 μm are strength-controlling in the material investigated. Two mechanistic regimes were manifest in the temperature dependence of the fracture stress. Up to 900° C, catastrophic transgranular crack propagation occurred from emplaced cracks. At 1000° C and above, subcritical crack growth occurred intergranularly and the extent of slow crack growth prior to catastrophic failure increased with increasing temperature. The influence of loading rate on slow crack growth and fracture stress was explored at 950 and 1100° C. Generally, the extent of slow crack growth decreased with increased loading rate until at a sufficiently high rate, catastrophic fracture occurred directly with no slow crack extension. These results are discussed in terms of the role of plastic accommodation in the crack extension process, a phenomenon which seems mechanistically dependent upon remnant amorphous (uncrystallized) phase at grain boundaries.
Excited-State Deactivation of Ruthenium(II) Polypyridyl Chromophores Bound to Nanocrystalline TiO2 Mesoporous Thin Films

Excitation of Ru(deeb)(bpy)22+, bis(2,2‘-bipyridine)(2,2‘-bipyridine-4,4‘-diethylester)ruthenium(II) hexafluorophosphate, bound to nanocrystalline TiO2 thin films and immersed in an acetonitrile bath at 25 °C under an argon atmosphere, results in the formation of a species, the transient spectral characteristics for which are, consistent with a metal-to-ligand charge transfer, MLCT, excited state. The spectrum decays by kinetics that are inconsistent with a simple first-order process. Modeling of the data as a function of irradiance has been accomplished assuming parallel unimolecular and bimolecular excited-state deactivation processes. The quantum yield for excited-state formation depends on the excitation irradiance, consistent with triplet−triplet annihilation processes that occur with k ≥ 1 × 108 s-1.
The SiO bond and electron density distributions

Electron density distributions, ϱ(r), have been calculated for the partially and fully geometry optimized molecules Si I O, Si II O2, H2Si III O3, H4Si IV O4, H6SIV2O7, H8Si VI O6, H10SiVI2O10 and H12Si VIII O8, using SCF Hartree-Fock wavefunctions calculated with a 6-311++G** basis set (the Roman numeral superscripts denote the coordination number of Si). The value of the electron density distribution, ϱ(r c), evaluated at (3,−1) critical (stationary) points, r c, along the SiO bonds of these molecules increases linearly with decreasing SiO bond length, R(SiO), from ϱ(r c)=0.50e/A3 for R(Si VIII O)=1.96A to ϱ(r c)=1.36e/A3 for R(Si II O)= 1.48A. A mapping of the Laplacian of the distribution, ∇2 ϱ(r), together with a determination of the bonded radii, rb(O), calculated for the oxide ions indicate that the fractional ionic character of the bond increases with increasing coordination number from ∼0.40 for an Si II O bond to ∼0.50 for an Si IV O bond to ∼0.60 for an Si VI O bond to ∼0.75 for a Si VIII O bond. Unlike the ionic and crystal radii of the oxide ion, rb(O) is not constant for a given coordination number but increases linearly with R(SiO) from rb(O)=0.86A for R(SiO)=1.48A to rb(O)= 1.20A for R(SiO)=1.96A. Concomitant with this increase in the size of the oxide ion, the atomic charge on the O atom increases as the volume of its basin expands and the fractional ionic character, ƒi(SiO), of the SiO bond increases. As ƒi(SiO) increases, not only is there a decrease in the value of ϱ(r) at r c, but also the sharpness (curvature) of the maximum in ϱ(r) radiating perpendicular to the bond and the sharpness of the minimum in ϱ(r) along the bond are both diminished. Electron density distribution calculations for five H6Si2O7 molecules with geometries fixed to match those observed for the nonequivalent `Si2O7 dimers' in coesite show that the value of ϱ(r c) for the bridging SiO bond increases as the SiOSi angle widens and R(SiO) shortens. The properties of ϱ(r) for the SiO bonds of the molecules are similar to those measured for coesite demonstrating that ϱ(r) is similar in both systems. The ellipticity of the electron density of the SiO bond decreases slightly as the angle widens with the cross-section of the bond becoming circular at 180°. Such an effect is consistent with the formation of weak π-bonds where the π-system perpendicular to the SiOSi plane becomes more dominant as the SiOSi angle narrows. Relief and level line contour −∇2 ϱ(r) maps calculated through the OSiO planes in H4SiO4 and H8SiO6 show that the electron density of the valence shell concentration of the oxide ion is enhanced in the directions of the Si atoms with the enhancement being greater for the Si IV O than for the Si VI O bond in conformity with the greater ionic character of the latter. Maps calculated for H12SiO8 show little dissipation of the valence shell of the oxide ion and little or no enhancement in the direction of the Si atom in agreement with the larger fractional ionic character of the Si VIII O bond and a nearly spherical distribution of the valence shell enhancement of ϱ(r) for the oxide ion.
Muscle strength after Btx injection in children with cerebral palsy

dose was determined according to the clinical approved, weightadapted protocol. Basic statistical analysis was done (p<0.05). Results: Maximum ankle dorsiflexion was significantly increased from −0.5±12.8 degrees before to 6.5±13.5 degrees at E1. There was a slight deterioration to 3.9 degrees 18 weeks after the BtA-injections. Minimum knee flexion in stance did not change significantly between E0 and E1, but there was a slight but not significant improvement of knee hyperextension during stance phase of 4.6 degrees between baseline and 18 weeks after BtA-injection. Discussion and conclusions: BtA-injection into the calf muscles is commonly accepted for the treatment of dynamic equinus in CP children. Corroborating the findings of previous studies a significantly improved ankle dorsiflexion was found in our study [3]. Despite improvement of ankle dorsiflexion, GR was not influenced 6 weeks after injection and only a slight reduction of GRwas found after 18weeks. However,manifest knee hyperextension (more that 1SD from norm) remained in most of the cases indicating that plantar-flexion knee-extension couple only partially influences GR. Other factors should be considered.Weakness of proximal gastrocnemius after BtA-injection could also have influenced the results.
NIF pointing and centering systems and target alignment using a 351-nm laser source

The operational requirements of the National Ignition Facility (NIF) place tight constraints upon its alignment system. In general, the alignment system must establish and maintain the correct relationships between beam position, beam angle, laser component clear apertures, and the target. At the target, this includes adjustment of beam focus to obtain the correct spot size. This must be accomplished for all beamlines in a time consistent with planned shot rates and yet, in the front end and main laser, beam control functions cannot be initiated until the amplifiers have sufficiently cooled so as to minimize dynamic thermal distortions during and after alignment and wavefront optimization. The scope of the task dictates an automated system that implements parallel processes. We describe reticle choices and other alignment references, insertion of alignment beams, principles of operation of the Chamber Center Reference System 2048 and Target Alignment Sensor, and the anticipated alignment sequence that will occur between shots.
Calcium signaling and gonadotropin secretion.

Abstract Agonist activation of pituitary gonadotrophs by gonadotropinreleasing hormone (GnRH) stimulates rapid InsP 3 -dependent peaks of calcium mobilization and luteinizing hormone (LH) release, followed by sustained increases in calcium-influx and hormone secretion. Receptor-mediated calcium entry through L-type and dihydropyridine-itisensitive calcium channels accounts for the sustained elevation of cytosolic calcium during GnRH action, and for most of the gonadotropin secretory response. Protein kinase C contributes to the phase of sustained LH release from GnRH-stimulated gonadotrophs, and also to gonadotropin synthesis. Calcium-dependent inactivation of L channels occurs during GnRH action, and appears to be a primary factor in the onset of desensitization of gonadotropin secretion.
Nicotine regulates collagen gene expression, collagenase activity, and DNA synthesis in cultured cardiac fibroblasts

Cardiac fibroblasts that reside in the interstitium are the cellular origin of collagen and other proteins of the extracellular matrix in the heart. We have previously shown thatin vitro gene expression, proliferation and even phenotypic features of cardiac fibroblasts are subject to regulation by biological factors such as hormones, growth factors and neurotransmitters. The influence of nicotine, the active ingredient of tobacco, on risk factors for cardiac diseases is well known.In vivo adverse effects of nicotine are as the result of its direct and indirect effects. The cellular and molecular mechanisms of direct effects of nicotine in the heart are widely unknown. The objective of this study was to investigate if nicotine has direct influence on cardiac fibroblasts. To this end, we studied the effects of nicotine on cultured cardiac fibroblasts. Northern hybridization analysis of RNA extracted from cardiac fibroblasts, enzymography of conditioned medium of cardiac fibroblasts and [3H]-thymidine incorporation into DNA of cardiac fibroblasts were used to examine the effects of nicotine on collagen gene expression, collagenase activity and DNA synthesis respectively. Treatment of cardiac fibroblasts with nicotine (10 μg/ml) led to a 31% (P<0.05) decrease in the abundance of mRNA for pro α1(I) but not pro α2(I) collagen compared with control untreated cells. Nicotine treatment of cardiac fibroblasts also led to decreased collagenase activity (62%, P<0.001) in the conditioned medium of those cells in culture. Studies with [3H]-thymidine incorporation into DNA of cardiac fibroblasts showed a nicotine-induced decrease (39%, P<0.001) in DNA synthesis in those cells. These findings suggest that cardiac fibroblasts are targets for the toxic effects of nicotine. The findings further point to the possibility that nicotine-induced alterations in cardiac fibroblasts' function and gene expression may contribute to the biological processes that ultimately lead to adverse effects of nicotine in the heart.
Structure determination of aquomet porcine hemoglobin at 2.8 A resolution.

Considerable attention is currently focused on hemoglobins from lower mammals, such as the pig, for potential use in cell-free blood substitute preparations safe for use in humans. As the first step in the elucidation of structure-function relationships in porcine hemoglobin, we have determined the three-dimensional structure of aquomet porcine hemoglobin at 2.8 A resolution. Overall, the porcine hemoglobin tetramer is structurally similar to that of human oxyhemoglobin, and the r.m.s. deviation of all backbone atoms (minus five residues at the amino and carboxyl termini of each subunit) is 0.8 A. This similarity is not unexpected given that human and porcine hemoglobins exhibit 85% sequence identity. However, regions of subtle structural differences are implicated in subtle functional differences between the two proteins, such as the 20 to 25% inhibition of the alkaline Bohr effect and the accompanying reduction in oxygen-linked chloride binding observed for porcine hemoglobin. The structural similarity of these two mammalian hemoglobins also rationalizes the novel hybridization behavior of pig and human subunits in transgenic pigs expressing both porcine and human hemoglobins in porcine erythrocytes.
Teachers' Progress toward Becoming Expert Strategy Teachers

In this article, I combine results from several years of study in an attempt to understand 11 teachers' progress toward becoming expert strategy teachers. The article is based on a 4-year staff development program involving 8 rural school districts in northern Michigan, during which 4-6 teachers were intensively studied annually. I use those intensive studies, as well as less formal observations of other teacher participants, to describe a continuum of 9 "points of progress" teachers seem to go through in learning to teach strategies to their lowest achievers. I argue that this continuum spans past collective thinking of the field regarding strategy instruction and foreshadows where strategy instruction must go if it is to achieve its potential.
An older view on distance perception: Age affects perception of walkable extents

affected by the specific energetic cost required to perform an action. In the current experiments, we examined the effect of age on distance perception. Older and younger adults were asked to verbally estimate distance to a target placed in a hallway. Results showed that older adults estimated distances to be farther compared to younger adults, but only for action-relevant extents. When subjects were asked to estimate distances on a carpet and a plastic surface, floor surfaces that decrease walking ability, such as plastic tarps, were judged to be farther away for older adults while such sensitivity was not as apparent in younger adults. Results suggest that perception is still sensitive to differences that affect ability even as a perceiver ages. Mila Sugovic & Jessica Witt Purdue University An Older View on Distance Perception: Age Affects Perception of Walkable Extents
Integrity of the National Resident Matching Program for Radiation Oncology: National Survey of Applicant Experiences.

Purpose The aim of this study was to examine the experiences of radiation oncology applicants and to evaluate the prevalence of behaviors that may be in conflict with established ethical standards. Methods and Materials An anonymous survey was sent to all 2013 applicants to a single domestic radiation oncology residency program through the National Resident Matching Program (NRMP). Questions included demographics, survey of observed behaviors, and opinions regarding the interview and matching process. Descriptive statistics were presented. Characteristics and experiences of respondents who matched were compared with those who did not match. Results Questionnaires were returned by 87 of 171 applicants for a 51% response rate. Eighty-two questionnaires were complete and included for analysis. Seventy-eight respondents (95.1%) reported being asked at least 1 question in conflict with the NRMP code of conduct. When asked where else they were interviewing, 64% stated that this query made them uncomfortable. Forty-five respondents (54.9%) reported unsolicited post-interview contact by programs, and 31 (37.8%) felt pressured to give assurances. Fifteen respondents (18.3%) reported being told their rank position or that they were "ranked to match" prior to Match day, with 27% of those individuals indicating this information influenced how they ranked programs. Half of respondents felt applicants often made dishonest or misleading assurances, one-third reported that they believed their desired match outcome could be improved by deliberately misleading programs, and more than two-thirds felt their rank position could be improved by having faculty from their home institutions directly contact programs on their behalf. Conclusions Radiation oncology applicants report a high prevalence of behaviors in conflict with written NRMP policies. Post-interview communication should be discouraged in order to enhance fairness and support the professional development of future radiation oncologists.
Self-Monitoring, Gender, and the Personal Consequences of Impression Management:

For an actress to be a success, she must have the face of a Venus, the brains of a Minerva, the grace of Terpsichore, the memory of a Macauley, the figure of Juno and the hide of a rhinoceros.—Ethe...
Cortical activation related to arm-movement combinations.

Recent studies support the long-standing hypothesis that continuous arm movements consist of overlapping, discrete submovements. However, the cortical activation associated with these submovements is unclear. We tested the hypothesis that electroencephalography (EEG) activity would more strongly correspond to the particular combinations of muscle electrical activity, the independent components (ICs) of surface electromyography (EMG), than the surface EMG from individual muscles alone. We examined data recorded from two normal subjects performing sustained submaximal contractions or continual, unpaced repetitive movements of the arm. Independent component analysis (ICA) was used to determine the ICs of the multichannel EMG recordings (EMGICs). ICA was also used to calculate the coupling between the simultaneously recorded EEG and the EMG from a single muscle (Subject 1) or the EMGICs (Subject 2). The EMGICs were either tonic or phasic. The significant couplings between the EEG and the EMGICs were different for each EMGIC. The distribution on the scalp of the coupling between the EEG and tonic EMGICs and those of the single-muscle EMG were similar and followed topographic patterns in sensorimotor regions. Couplings between the EEG and phasic EMGICs were bifrontal, lateral, and bioccipital and were significantly stronger than the coupling between a single muscle's EMG and the EEG (p < 2 x 10 -5 ) or another EMG combination derived from principal component analysis. These preliminary results support the notion that electrophysiological cortical activations are more significantly related to the ICs of muscle activations than to the activations of individual muscles alone.