cssi/SciSciGPT-SciSciNet huggingface dataset:
Type I Clathrates as Novel Silicon Anodes: An Electrochemical and Structural Investigation

Silicon clathrates contain cage-like structures that can encapsulate various guest atoms or molecules. An electrochemical evaluation of type I silicon clathrates based on Ba8Al y Si46-y as the anode material for lithium-ion batteries is presented here. Postcycling characterization with nuclear magnetic resonance and X-ray diffraction shows no discernible structural or volume changes even after electrochemical insertion of 44 Li (≈1 Li/Si) into the clathrate structure. The observed properties are in stark contrast with lithiation of other silicon anodes, which become amorphous and suffer from large volume changes. The electrochemical reactions are proposed to occur as single phase reactions at approximately 0.2 and 0.4 V versus Li/Li+ during lithiation and delithiation, respectively, distinct from diamond cubic or amorphous silicon anodes. Reversible capacities as high as 499 mAh g-1 at a 5 mA g-1 rate were observed for silicon clathrate with composition Ba8Al8.54Si37.46, corresponding to ≈1.18 Li/Si. These results show that silicon clathrates could be promising durable anodes for lithium-ion batteries.
The August 1975 Oroville earthquakes

abstract On August 1, 1975, a magnitude 5.9 ( m b ) earthquake occurred approximately 8 km SSE of the town of Oroville, California. This earthquake and its associated foreshock-aftershock sequence are of particular interest because of their possible relation to the impounding of the 4.3 billion m 3 Lake Oroville. Hypocenter locations for 336 aftershocks that occurred during August define a fault plane striking N3°E and dipping 60° to the west to a depth of 10 km. Dimensions of the epicentral area are approximately 7 km in an east-west direction by 15 km in a north-south direction. The fault plane passes beneath Oroville Dam at 5-km depth, and if projected up dip, would crop out beneath the reservoir to the east. The distribution in space and time of foreshocks and aftershocks suggests that rupture began at depth and progressed up dip and to the north and south.
Comparing the Ethics of Citizen Photojournalists and Professional Photojournalists: A Coorientational Study

In the digital news environment, amateur images—citizen photojournalism—appear next to professional photojournalists' photos, contributing to a probable tension and sense of professional threat among professional photojournalists. Using the coorientation approach, this study explores the ethical values of citizen photojournalists and professional photojournalists, the extent to which they agree about these values, how accurate they are in assessing each others' values, and how congruent they perceive they are with each other.
Molecular Vibration Spectra by Electron Tunneling

The conductance of metal-metal oxide-metal tunneling junctions has been observed to increase at certain characteristic bias voltages. These voltages are identified with vibrational frequencies of molecules contained in the barrier.
Partial Purification and Characterization of Cathepsin D-Like and B-Like Acid Proteases from Surf Clam Viscera

Different proteases were isolated and purified from viscera of surf clam, Spisula solidissima. These proteases were similar to cathepsins D and B, with molecular weights of −36,700 and −17,400 daltons, respectively. Optimum activity of enzymes towards hemoglobin and casein occurred from pH 2.5–3.0 and temperature 44–46°C. Cathepsin D-like protease, a carboxyl protease, was insensitive to most protease inactivators, but extremely sensitive to pepstatin. Cathepsin B-like protease, a thiol protease, was activated by thiol-reducing agents and metal chelators, but was sensitive to many reagents such as iodoacetamide, Tosyl-phenylalanine chloromethyl ketone, Tosyl-lysine chloromethyl ketone, phenylmethanesulphonyl fluoride, leupeptin and heavy metals.
A poly-His tag method for obtaining the C-terminal lobe of human transferrin

Human serum transferrin is an essential bilobal protein that transports iron in the circulation for delivery to iron-requiring cells. Obtaining the C-terminal lobe of human transferrin in verified native conformation has been problematic, possibly because its 11 disulfide bonds lead to misfolding when the lobe is expressed without its accompanying N-lobe. A recently reported method for preparing the C-lobe free of extraneous residues, with normal iron-binding properties and capable of delivering iron to cells, makes use of a Factor Xa cleavage site inserted into the interlobal connecting strand of the full-length protein. An inefficient step in this method requires the use of ConA chromatography to separate the cleaved lobes from each other, since only the C-lobe is glycosylated. Inserting a 6-His sequence near the start of the N-lobe enhances recovery of the recombinant transferrin from other proteins in the culture medium of the BHK21 cells expressing the mutant transferrin. The new procedure is more economical in time and effort than its predecessor, and offers the additional advantage of isolating C-lobe expressed with or without its glycan chains.
Low-momentum interaction in few-nucleon systems

The low-momentum nucleon-nucleon interaction ${V}_{\text{low}\phantom{\rule{0.3em}{0ex}}k}$ is applied to three- and four-nucleon systems. We investigate the $^{3}\mathrm{H}$, $^{3}\mathrm{He}$, and $^{4}\mathrm{He}$ binding energies for a wide range of the momentum cutoffs. By construction, all low-energy two-body observables are cutoff independent, and therefore, any cutoff dependence is due to missing three-body or higher-body forces. We argue that for reasonable cutoffs ${V}_{\text{low}\phantom{\rule{0.3em}{0ex}}k}$ is similar to high-order interactions derived from chiral effective field theory. This motivates augmenting ${V}_{\text{low}\phantom{\rule{0.3em}{0ex}}k}$ by corresponding three-nucleon forces. The set of low-momentum two- and three-nucleon forces can be used in calculations of nuclear structure and reactions. We find that three-nucleon force contributions are perturbative for small cutoffs.
III. `Hellman's scheme breaks DES in its basic form¿

The time-memory tradeoff scheme of Prof. Martin E. Hellman, for practical purposes, breaks DES in its present basic form. It should be pointed out, though, that a time-memory tradeoff can be used to break any block ciphers that have similar key lengths and can reduce deciphering time by a significant factor.
Centrosome-specific perturbations during in vitro maturation of mouse oocytes exposed to cocaine.

Abstract Previous studies indicating that cocaine may perturb meiotic chromosome segregation in mammalian oocytes prompted an analysis of the effects of cocaine on mouse oocytes matured in vitro under defined exposure conditions. Cumulus-enclosed mouse oocytes were matured in vitro in the continuous presence of cocaine and assessed for meiotic cell cycle progression and centrosome–microtubule organization using a combination of cytogenetic and fluorescence microscopic techniques. Both of these approaches demonstrated that cocaine had little effect on meiotic cell cycle progression to metaphase of meiosis-2 except at the highest dose tested (1000 μg/ml) where progression from metaphase-1 to metaphase-2 was inhibited. Cytogenetic analyses further showed that bivalent segregation was moderately affected and the incidence of premature centromere separation was significantly decreased following cocaine treatment. Under conditions of cocaine exposure, striking changes in meiotic spindle structure and cytoplasmic centrosome organization were observed. A 36% reduction in spindle length was associated with a loss of nonacetylated microtubules and fragmentation of spindle pole centrosomes. Moreover, in oocytes exposed to cocaine during maturation, a doubling in cytoplasmic centrosome number was observed. These results are discussed with respect to the relative roles of chromosomes and centrosomes in establishing and maintaining functional microtubule organization during meiosis in oocytes.
Substrate and Metal Complexes of 3-Deoxy-d-manno-octulosonate-8-phosphate Synthase from Aquifex aeolicus at 1.9-Å Resolution IMPLICATIONS FOR THE CONDENSATION MECHANISM

Abstract 3-Deoxy-d-manno-octulosonate-8-phosphate synthase (KDO8PS) from the hyperthermophilic bacteriumAquifex aeolicus differs from its Escherichia coli counterpart in the requirement of a divalent metal for activity (Duewel, H. S., and Woodard, R. W. (2000)J. Biol. Chem. 275, 22824–22831). Here we report the crystal structure of the A. aeolicus enzyme, which was determined by molecular replacement using E. coli KDO8PS as a model. The structures of the metal-free and Cd2+ forms of the enzyme were determined in the uncomplexed state and in complex with various combinations of phosphoenolpyruvate (PEP), arabinose 5-phosphate (A5P), and erythrose 4-phosphate (E4P). Like the E. coli enzyme, A. aeolicus KDO8PS is a homotetramer containing four distinct active sites at the interface between subunits. The active site cavity is open in the substrate-free enzyme or when either A5P alone or PEP alone binds, and becomes isolated from the aqueous phase when both PEP and A5P (or E4P) bind together. In the presence of metal, the enzyme is asymmetric and appears to alternate catalysis between the active sites located on one face of the tetramer and those located on the other face. In the absence of metal, the asymmetry is lost. Details of the active site that may be important for catalysis are visible at the high resolution achieved in these structures. Most notably, the shape of the PEP-binding pocket forces PEP to assume a distorted geometry at C-2, which might anticipate the conversion from sp 2 tosp 3 hybridization occurring during intermediate formation and which may modulate PEP reactivity toward A5P. Two water molecules are located in van der Waals contact with the siand re sides of C-2PEP, respectively. Abstraction of a proton from either of these water molecules by a protein group is expected to elicit a nucleophilic attack of the resulting hydroxide ion on the nearby C-2PEP, thus triggering the beginning of the catalytic cycle.
The subacute toxicity of 1,1-dimethylhydrazine.

Abstract Daily injections of 70, 50, 30, or 10 mg UDMH/kg resulted in the death of 9, 6, 5, and 0 rats, respectively, in each group of 10. All deaths occurred within the first 3 days. Animals surviving the first 3 days began to gain weight even though daily dosing was continued. Animals receiving more than 10 mg/kg/day were markedly diuretic throughout the 21-day experimental period. Blood urea nitrogen and serum glutamic-oxaloacetic transaminase (SGOT) levels were significantly elevated in the 50 mg/kg dose group at 21 days. SGOT also appeared somewhat elevated in the 30 mg/kg/ day group. Histopathologic studies showed some evidence of early lipid infiltration in the tubular epithelium of the kidney. Thus, although some animals appear to adjust to relatively high daily doses of UDMH, biochemical and histologic evidence indicates mild kidney damage in these animals.
Biomineralization proteins: from vertebrates to bacteria

Biomineralization processes are frequently found in nature. Living organisms use various strategies to create highly ordered and hierarchical mineral structures under physiologic conditions in which the temperatures and pressures are much lower than those required to form the same mineralized structures by chemical synthesis. Although the mechanism of biomineralization remains elusive, proteins have been found responsible for the formation of such mineral structures in many cases. These proteins are active components in the process of biomineralization. The mechanisms by which their function can vary from providing active organic matrices that control the formation of specific mineral structures to being catalysts that facilitate the crystallization of certain metal ions. This review summarizes the current understanding of the functions of several representative biomineralization proteins from vertebrates to bacteria in the hopes of providing useful insight and guidance for further elucidation of mechanisms of biomineralization processes in living organisms.
Predictors of Domestic Violence Prosecution in a State Court

Successful prosecution of state-level domestic violence cases typically requires participation from the victim. However, given the unique factors associated with these cases, the assistance of a victim advocate may be beneficial in maintaining victim cooperation. This research examines 353 cases to determine if victim cooperation and case disposition could be predicted by victim advocacy, victim injuries, defendant's use of a weapon, and the presence of witnesses. Findings from logistic regression analysis suggest that victim assistance was significantly related to both victim cooperation and case disposition. Further, victim cooperation and the presence of witnesses significantly increased the likelihood of a conviction.
Pathways for solar photovoltaics

Solar energy is one of the few renewable, low-carbon resources with both the scalability and the technological maturity to meet ever-growing global demand for electricity. Among solar power technologies, solar photovoltaics (PV) are the most widely deployed, providing 0.87% of the world's electricity in 2013 and sustaining a compound annual growth rate in cumulative installed capacity of 43% since 2000. Given the massive scale of deployment needed, this article examines potential limits to PV deployment at the terawatt scale, emphasizing constraints on the use of commodity and PV-critical materials. We propose material complexity as a guiding framework for classifying PV technologies, and we analyze three core themes that focus future research and development: efficiency, materials use, and manufacturing complexity and cost.
A method for the symbolic representation and analysis of linear periodic feedback systems

LINEAR FEEDBACK systems with periodic sampling, finite pulsing, finite pulse clamping and similar variations have been a subject of increasing interest in recent years. Applications in such important areas as digital control and time-division multiplexing have motivated continued research and development. This is particularly true for certain types of systems where the theory is extensive and well developed. Unfortunately, there are many types of systems which have received little or no attention.
N incorporation, composition and electronic structure in N-doped TiO2(001) anatase epitaxial films grown on LaAlO3(001)

Abstract We have investigated the properties of N-doped TiO 2 anatase grown by plasma-assisted molecular beam epitaxy on LaAlO 3 (0 0 1) substrates. Phase-pure epitaxial films in which N substitutes for O with no secondary phase formation nucleate only over a narrow range of fluxes. N substitution for O results in N 2p derived states off the top of the anatase valence band and the associated red shift in the optical bandgap.
Extending marine species distribution maps using non-traditional sources.

BACKGROUND Traditional sources of species occurrence data such as peer-reviewed journal articles and museum-curated collections are included in species databases after rigorous review by species experts and evaluators. The distribution maps created in this process are an important component of species survival evaluations, and are used to adapt, extend and sometimes contract polygons used in the distribution mapping process. NEW INFORMATION During an IUCN Red List Gulf of Mexico Fishes Assessment Workshop held at The Harte Research Institute for Gulf of Mexico Studies, a session included an open discussion on the topic of including other sources of species occurrence data. During the last decade, advances in portable electronic devices and applications enable 'citizen scientists' to record images, location and data about species sightings, and submit that data to larger species databases. These applications typically generate point data. Attendees of the workshop expressed an interest in how that data could be incorporated into existing datasets, how best to ascertain the quality and value of that data, and what other alternate data sources are available. This paper addresses those issues, and provides recommendations to ensure quality data use.
USE OF 13 C-GLUCOSE BREATH TESTS IN THE CHARACTERIZATION OF ABSORPTION OF CARBOHYDRATE IN FORMULA BY INFANTS WITH DIARRHEA

The appearance time (AT) of the first detectable levels of 13CO2 (> .01% dose/min) in breath following the oral administration of UL-13C-glucose (13C-G, 5 mg/kg) provides an estimate of the time required for orally administered 13C-G to reach the primary site of absorption and utilization. The AT for 13C-G will increase as the absorption of glucose occurs at more distal sites, until a maximum is reached when the glucose enters the colon where it is rapidly oxidized to CO2. The AT of 13C-G administered alone and with formula (60-240 ml) has been used to characterize glucose absorption and utilization in 6 infants (16-93 d) with diarrhea and malnutrition (arm/FOC < 0.28). A maximum value of 27 min for the AT of 13C-G from formula was determined in an infant with congenital glucose-galactose malabsorption, in whom colonic utilization of CHO was demonstrated by breath H2 production and partial recovery of 13C in stool. AT for 13C-G in formula, obtained for the 6 infants measured, were 5,7,15,20,30,30 min, respectively, providing indirect evidence for the colonic utilization of dietary glucose in at least 2 of the infants. In the absence of formula, AT for 13C-G decreased to 10,15,10,10,2,10 min, respectively. This suggests that the CHO load in the formula may have contributed to the small bowel malabsorption of glucose in those infants with near maximal formula AT values.
Student Reactions to Standards‐Based Mathematics Curricula: The Interplay Between Curriculum, Teachers, and Students

As standards-based mathematics curricula are used to guide learning, it is important to capture not just data on achievement but data on the way in which students respond to and interact in a standards-based instructional setting. In this study, sixth and seventh graders reacted through letters to using one of two standards-based curriculum projects (Connected Mathematics Project or Six Through Eight Mathematics). Letters were analyzed by class, by teacher, and by curriculum project. Findings suggest that across classrooms students were positive toward applications, hands-on activities, and working collaboratively. The level of students' enthusiasm for the new curricula varied much from class to class, further documenting the critical role teachers play in influencing students' perceptions of their mathematics learning experiences. The results illustrate that, while these curricula contain rich materials and hold much promise, especially in terms of their activities and applications, their success with students is dependent on the teacher.
Molecular beam epitaxy of gallium nitride by electron cyclotron resonance plasma and hydrogen azide

Abstract GaN films were grown on (0001) sapphire by molecular beam epitaxy (MBE). Two sources of activated nitrogen were investigated: an electron cyclotron resonance (ECR) plasma, and hydrogen azide (HN3). With the ECR plasma source, typical growth rates were ∼ 0.1 μm/h. Films grown in this manner showed significant surface damage from ions, and little if any photoluminescence. With HN3, growth rates were ∼ 0.25 μm/h. Azide-grown films showed smooth surfaces, and sharp band-to-band photoluminescence. This is the first reported use of HN3 to grow III–V nitrides by MBE, and it shows great promise as a nitrogen source.
Do general surgery residency programs adequately train surgeons to perform anorectal surgery

The management of anorectal disease remains a major component in the practice of the general surgeon. To assess the adequacy of general surgery residencies in addressing this educational need, data were obtained from the Residency Review Committee (RRC) for surgery on the anorectal experience of all graduating residents in accredited United States programs for a recent five-year period (1987–1991). The mean number of anorectal procedures in which a resident participated throughout the residency was 30.0. This is then further subdivided by type of procedure. It is concluded that general surgery residency programs tend to provide an inadequate training experience in anorectal surgery.
Optimal sequencing of blocked 2m-k fractional factorial designs

Abstract In this paper, we consider the problem of sequencing blocks for regular 2 m - k fractional factorial designs occurring in 2 p blocks of size 2 m - k - p . An optimality criterion is introduced for sequencing blocks within a given design and tables of optimal blocking sequences are provided for most of the designs given in Sun et al. (Technometrics 39 (1997) 298).
Pathogen-specific risk of chronic gastrointestinal disorders following bacterial causes of foodborne illness

The US CDC estimates over 2 million foodborne illnesses are annually caused by 4 major enteropathogens: non-typhoid Salmonella spp., Campylobacter spp., Shigella spp. and Yersinia enterocoltica. While data suggest a number of costly and morbid chronic sequelae associated with these infections, pathogen-specific risk estimates are lacking. We utilized a US Department of Defense medical encounter database to evaluate the risk of several gastrointestinal disorders following select foodborne infections. We identified subjects with acute gastroenteritis between 1998 to 2009 attributed to Salmonella (nontyphoidal) spp., Shigella spp., Campylobacter spp. or Yersinia enterocolitica and matched each with up to 4 unexposed subjects. Medical history was analyzed for the duration of military service time (or a minimum of 1 year) to assess for incident chronic gastrointestinal disorders. Relative risks were calculated using modified Poisson regression while controlling for the effect of covariates. A total of 1,753 pathogen-specific gastroenteritis cases (Campylobacter: 738, Salmonella: 624, Shigella: 376, Yersinia: 17) were identified and followed for a median of 3.8 years. The incidence (per 100,000 person-years) of PI sequelae among exposed was as follows: irritable bowel syndrome (IBS), 3.0; dyspepsia, 1.8; constipation, 3.9; gastroesophageal reflux disease (GERD), 9.7. In multivariate analyses, we found pathogen-specific increased risk of IBS, dyspepsia, constipation and GERD. These data confirm previous studies demonstrating risk of chronic gastrointestinal sequelae following bacterial enteric infections and highlight additional preventable burden of disease which may inform better food security policies and practices, and prompt further research into pathogenic mechanisms.
Liquid Composite Molding control methodologies using Vacuum Induced Preform Relaxation

A major limitation with Vacuum Infusion Processes (VIPs) is the inability to dynamically control the resin flow during infusion. A new method called Vacuum Induced Preform Relaxation (VIPR) has demonstrated that one can influence the permeability of the reinforcing fabric during infusion and hence be able to manipulate the resin flow. The VIPR process uses an external vacuum chamber that seals against the flexible molding surface of a VIP mold and applies a secondary vacuum to locally reduce the compaction pressure on the fibers which increases the permeability of that region steering resin flow to that region. In this paper flow control methodologies are introduced with VIPR for online flow correction. The VIPR process is coupled with an automated gantry system and control methodologies to exercise flow control during infusion. The capability of the automated flow control is demonstrated with two online flow control methodologies.
Nanopore Fabrication in Hollow Integrated Waveguides

We demonstrate the fabrication of micropores/nanopores in hollow antiresonant reflecting optical waveguides (ARROWs) through a combination of reactive ion etching and focused ion beam etching. Optical loss measurements indicate insignificant change in the waveguide loss.
A Distributed Medium Access Control Protocol for Wireless Networks of Cooperative Radar Systems

The medium access control issues of a distributed wireless network of cooperative tracking radars are investigated by modeling the individual radars as part of a system-of-systems rather than as independently operating sensors. Two fundamental observations are made regarding the radar control traffic flow and the radar data traffic flow: the pulse repetition frequency (PRF) is found to be bounded by the radar control packet delay and the radar data traffic is bursty but not well-suited to contention-based medium access. Motivated by these observations, we propose a novel medium access protocol: the Cooperative Radar Medium Access Control (CR-MAC) protocol. CR-MAC is an application-aware protocol that combines the throughput of a time division medium access (TDMA) protocol with the reduced delay of a contention-based protocol. Control packet delay as well as data traffic throughput are analyzed and CR-MAC is found to outperform conventional TDMA and CSMA.
A LEED crystallography study of the (2×2)−C2H3 structure obtained after ethylene adsorption on Rh(111)☆

The structure of the Rh(111)-(2 × 2)-C2H3 overlayer that was obtained upon the adsorption of ethylene has been determined using a LEED intensity analysis. In agreement with a prior HREELS study, an ethylidyne (CCH3) species is found to stand perpendicularly above an hcp hollow site with a carbon-carbon distance of 1.45±0.10 A and a metal-carbon distance of 2.03±0.07 A. The Zanazzi-Jona and Pendry R-factors for this structure are 0.49 and 0.52, respectively. By comparison with similar organometallic complexes, the relatively short carbon-carbon distance and long metal-carbon distance can be explained by σ−π hyperconjugation of the surface ethylidyne fragment.
Conflict of interest in the evaluation and dissemination of “model” school-based drug and violence prevention programs

Conflict of interest refers to a set of conditions in which professional judgment concerning the validity of research might be influenced by a secondary competing interest. The competing interest that has received most attention in the literature addressing the prevalence and effects of such conflicts on the practice of empirical research has been that of financial relationships between investigators and research sponsors. The potential for conflicts of interest to arise in the evaluation of drug prevention programs was raised by Moskowitz in this journal in 1993, but to date there has been no attempt made to estimate the scope of this problem. The present study addressed this issue using a sample of “model” school-based drug and violence prevention interventions by first, identifying the types or relationships that exist between program developers and program distributors, and, second, by assessing how many of the evaluations of these programs published in peer-reviewed journals had been conducted by the developers of the programs compared to independent evaluation teams. The data presented indicate that there are relatively few published evaluations that do not involve program developers and that there are few instances in which there is complete separation between the program developer and program distributor. Using the open systems model of the Institute of Medicine Committee on Research Integrity as a framework, it is argued that the culture and norms of the program developer and those of the program evaluator are fundamentally distinct and therefore failure to separate these roles produces high potential for conflict of interest to arise.
A fracture mechanical analysis of fouling release from nontoxic antifouling coatings

Abstract The successor to toxic antifouling coatings has been pursued for many years. Attempts to create perfectly nonfouling surfaces from polymers containing fluorine and silicone have been made, but marine fouling adheres to all surfaces yet investigated. The focus of our efforts has shifted from the coating surface to the joint between a fouling organism and a coating. We are studying methods to facilitate the fracture of this joint by controlling the chemical and mechanical properties of the polymer. This paper focuses on the fracture mechanics of the joint between a fouling organism and a coating surface, and shows that fluoropolymer and silicone coatings use significantly different mechanisms to release fouling. The paper concludes with a discussion of approaches to the design of successful fluoropolymer or silicone nontoxic antifouling coatings based on their preferred fracture modes.
Residual design strength of cement-based materials for nuclear waste storage systems

Abstract Calcium leaching of concrete may be critical for the mechanical integrity of hazardous waste storage systems, in which cement-based materials are employed as construction material or grouting material. Results from a recent triaxial strength test campaign on calcium depleted cementitious materials highlight that these materials exhibit decohesion and frictional softening and become increasingly pressure sensitive. But the overall emerging picture is one of a material with a residual, finite accountable strength, which is well above either the particulate or the matrix strength. This allows us to propose a ‘safe’ lower bound for calcium depleted cement-based composites, which may serve for the durability performance design of concrete structures subjected to calcium leaching-one critical design scenario of e.g. nuclear waste storage systems.
Designing two-dimensional materials that spring rapidly into three-dimensional shapes

One of the hallmarks of living organisms, including humans, is the ability to actively respond and adapt to stress. Even plants, which lack a nervous system, react to different stimuli by changing their shape. Some well-known examples are the wrinkled edges of leaves as a response to compression during growth, wrinkles of skin to accommodate flexing and bending movements or age-drying stresses, or the mimosa's rapid folding of its leaves via propagating waves of osmotic pressure when touched. Similar phenomena have been used in engineered artificial two-dimensional (2D) materials that can respond to external stimuli, but these applications typically are simple, slow, and work only along one dimension. On page 154 of this issue, Xu et al. ( 1 ) demonstrate a new paradigm of designing functional materials that can quickly snap into complex 3D architectures via localized buckling.
Wall Effects on Flow Past Solid Spheres at Finite Reynolds Number

Axisymmetric, steady flow of a Newtonian fluid past a solid sphere that is either suspended in a tube by an upflowing liquid (the fluidized sphere problem) or falling in a tube (the falling sphere problem) is determined by finite element analysis. The new results show that several correlations for drag presented in the literature are inaccurate (i) for any value of the ratio of the diameter of the tube to that of the sphere, 1/λ, when inertial effects are moderate (Re ≥ 30) and (ii) for 1/λ < 3.3 when Re is small. Two new correlations accounting for wall effects on drag for fluidized and falling spheres are presented that are valid when 0 ≤ Re ≤ 100 and 12.5 ≥ 1/λ ≥ 1.42. The effects of λ and Re on the onset of wake formation and wake characteristics are studied in detail. The results show that, as 1/λ decreases, the Re for the onset of wake formation increases, whereas the length of the wake decreases. Calculations carried out to simulate the effect of a wire used to support a fluidized sphere show that ...
Comparisons of Speed-Spacing Relations Under General Car Following Versus Lane Changing

Data from two freeway locations show that absent lane changing, the relationships between congested speed and spacing are linear in most ranges of congested speed. The relationships are also found to be statistically indifferent across lanes, indicating that a single general model would suffice for all lanes. Moreover, speed-spacing relationships for different types of lane changers (discretionary versus mandatory due to merging and diverging) are also found to be statistically indifferent. Anticipation and relaxation periods, defined as durations of perturbed car-following behavior before and after a lane-change maneuver, were measured for lane changers and the vehicles immediately behind the followers. Lane changers exhibited anticipation and relaxation periods of 8 and 14 s, respectively. The followers in the initial lanes exhibited anticipation and relaxation periods of 4 and 8 s, which are smaller than the periods for the followers in the target lanes (12 and 16 s) as well as the periods for the lane changers. The findings suggest that car-following behavior on a freeway can be predicted according to Newell's simplified car-following theory, and a single model can be used without much loss of accuracy for different lanes. The findings also suggest that the anticipation and relaxation processes are independent of lane-changing types but are different for lane changers and followers.
High-temperature mass spectrometry—I. Free vaporization studies of graphites☆

Abstract Some of the differences in the published data on the free vaporization of conventional (ATJ, ZTA, UT-6) and pyrolytic graphites have been resolved. Relative ion intensities, apparent rates of vaporization, and activation energies of vaporization have been measured for carbon species C 1 through C 5 , for conventional graphites in the temperature range 2800°–3000°K, and for pyrolytic graphites in the temperature range 2600°–3260°K. Differences in the free evaporation behavior of the two types of graphites are discussed. For the first time, evidences for carbon evaporation from the new ‘white’ allotropic form of carbon are presented; some of the anomalous vaporization behavior observed with both types of graphites is attributed to the vaporization of carbon from this new allotropie form of carbon. Plausible explanations are presented to account for the differences in activation energies of vaporization for C 4 and C 5 molecules for pyrolytic and conventional graphites. For conventional graphites at temperatures above about 2950° ± 50° K , the rates of vaporization of carbon species were found to increase abruptly, and the total mass-loss appears to occur by vaporization of carbon and ejection of crystallites.
Diet: The Neglected Variable in Chemical Safety Evaluations:

The objectives of this review are to alert the community of toxicologic pathologists to the types and significance of various diets fed to experimental animals used in safety evaluations of drugs and other chemicals, to acquaint investigators with dietary nutrients and contaminants of significance to research animals, to review some of the consequences of improper or inadequate diets on results of safety evaluations, and, finally, to offer a brief introduction to a highly promising new digital specimen technology for evaluating histopathology of tissues from animals used in safety evaluations with the aid of computers. Results that form the basis for this review have accumulated for more than 4 decades during research conducted during appointments at the University of Missouri, Columbia; Auburn University; Massachusetts Institute of Technology; and Boston University School of Medicine. The methods used in these studies have generally been state-of-the-art at the time the studies were conducted and involved an integration of techniques and methods used in fundamental nutrition, toxicology, and experimental pathology. Some of these investigations have shown that contaminants, naturally occurring and man-made, intentional and nonintentional, do occur in commercial animal diets; that essential nutrients, including total calories, protein and fat, can be provided in less or more than adequate amounts for the species of animal used in safety evaluations; and that such variables can influence responses to chemicals through effects on xenobiotic metabolism, immunocompetence, secondary diseases, and other factors. Under such conditions, serious differences in final interpretation of human risk for a drug or other chemical can contribute to failure to gain approval for a potentially valuable therapeutic agent. This review discusses the significance of various dietary components with examples of their effects on response of the animal to chemicals and demonstrates why nutrients, new technologies for assessing their effects, and other components in the diet should be accorded greater consideration by investigators and regulators.
A Nomenclature for Conformations of Pyranoid Sugars and Derivatives

A system is presented for designating, with symbols, all chair and boat conformations of all pyranoid sugars and derivatives. For chairs, these symbols are CA and CE : for boats: B 1 A , B 1 E , B 2 A , B 2 E , B 3 A , and B 2 E . Symbols A and E describe an axial or equatorial "glycosidic" group of the α-anomers (D and L series).
The cortical response to direct stimulation of the corpus callosum in the cat

Abstract The cortical response to direct stimulation of the corpus callosum consists of a brief surface-positive spike which originates deep in the cortex, followed by a slower positive-negative wave sequence which derives from structures extending to varying depths of cortex. The spike is assigned to dromic and antidromic axonal and possibly cell body discharge. The wave sequence is assumed to represent predominantly a response propagated upward along apical dendrites. The excitability cycle, strychnine spike driving, and post-tetanic potentiation phenomena are described, and the direct callosal response is compared with that elicited by homatotopic cortical stimulation. The antidromic callosal response is described in preparations in which dromic fibers had previously been allowed to degenerate. The response is remarkably similar to the normal mixed dromic and antidromic response, and it is inferred that the latter may be mediated synaptically via retrograde axonal collaterals. The interpretation of potential reversal in the cortical volume conductor is considered in relation to the probable anatomical substrate of the callosal response.
New State Spaces: Urban Governance and the Rescaling of Statehood. By Neil Brenner

The article reviews the book "New State Spaces: Urban Governance and the Rescaling of Statehood," by Neil Brenner.
Implications of dose-dependent target tissue absorption for linear and non-linear/threshold approaches in development of a cancer-based oral toxicity factor for hexavalent chromium.

Abstract Dose-dependent changes in target tissue absorption have important implications for determining the most defensible approach for developing a cancer-based oral toxicity factor for hexavalent chromium (CrVI). For example, mouse target tissue absorption per unit dose is an estimated 10-fold lower at the CrVI dose corresponding to the federal maximum contaminant level (MCL) than at the USEPA draft oral slope factor (SFo) point of departure dose. This decreasing target tissue absorption as doses decrease to lower, more environmentally-relevant doses is inconsistent with linear low-dose extrapolation. The shape of the dose–response curve accounting for this toxicokinetic phenomenon would clearly be non-linear. Furthermore, these dose-dependent differences in absorption indicate that the magnitude of risk overestimation by a linear low-dose extrapolation approach (e.g., SFo) increases and is likely to span one or perhaps more orders of magnitude as it is used to predict risk at progressively lower, more environmentally-relevant doses. An additional apparent implication is that no single SFo can reliably predict risk across potential environmental doses (e.g., doses corresponding to water concentrations ⩽ the federal MCL). A non-linear approach, consistent with available mode of action data, is most scientifically defensible for derivation of an oral toxicity factor for CrVI-induced carcinogenesis.
Design and initial testing of a synchrotron radiation absorber for the CESR B-factory

Operating at 8 GeV with 1 amp of beam current, the CESR B-factory produces highly intense synchrotron radiation (SR). In response to other vacuum chamber design concerns, a discrete bar absorber has been designed to receive the x rays in the transition region. The absorber is an actively cooled copper extrusion. Finite element analysis has been used to predict the thermal and structural response of the absorber. Elastic/plastic stress analyses predicted localized plastic deformation and since operation is cyclic, fatigue failure has been considered. Preliminary testing using a rastered electron beam for both steady state and fatigue testing has begun.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Intravenous migraine therapy in children with posttraumatic headache in the ED

Abstract Background More than 3.8 million children sustain traumatic brain injuries annually. Treatment of posttraumatic headache (PTH) in the emergency department (ED) is variable, and benefits are unclear. Objective The objective of the study is to determine if intravenous migraine therapy reduces pain scores in children with PTH and factors associated with improved response. Methods This was a retrospective study of children, 8 to 21 years old, presenting to a tertiary pediatric ED with mild traumatic brain injury (mTBI) and PTH from November 2009 to June 2013. Inclusion criteria were mTBI (defined by diagnosis codes) within 14 days of ED visit, headache, and administration of one or more intravenous medications: ketorolac, prochlorperazine, metoclopramide, chlorpromazine, and ondansetron. Primary outcome was treatment success defined by greater than or equal to 50% pain score reduction during ED visit. Bivariate analysis and logistic regression were used to determine predictors of treatment success: age, sex, migraine or mTBI history, time since injury, ED head computed tomographic (CT) imaging, and pretreatment with oral analgesics. Results A total of 254 patients were included. Mean age was 13.8 years, 51% were female, 80% were white, mean time since injury was 2 days, and 114 patients had negative head CTs. Eighty-six percent of patients had treatment success with 52% experiencing complete resolution of headache. Bivariate analysis showed that patients who had a head CT were less likely to respond (80% vs 91%; P = .008). Conclusions Intravenous migraine therapy reduces PTH pain scores for children presenting within 14 days after mTBI. Further prospective work is needed to determine long-term benefits of acute PTH treatment in the ED.
Comprehensive, powerful, efficient, intuitive: A new software framework for clinical imaging applications

One of the greatest challenges for a software engineer is to create a complex application that is comprehensive enough to be useful to a diverse set of users, yet focused enough for individual tasks to be carried out efficiently with minimal training. This "powerful yet simple" paradox is particularly prevalent in advanced medical imaging applications. Recent research in the Biomedical Imaging Resource (BIR) at Mayo Clinic has been directed toward development of an imaging application framework that provides powerful image visualization/analysis tools in an intuitive, easy-to-use interface. It is based on two concepts very familiar to physicians - Cases and Workflows. Each case is associated with a unique patient and a specific set of routine clinical tasks, or a workflow. Each workflow is comprised of an ordered set of general-purpose modules which can be re-used for each unique workflow. Clinicians help describe and design the workflows, and then are provided with an intuitive interface to both patient data and analysis tools. Since most of the individual steps are common to many different workflows, the use of general-purpose modules reduces development time and results in applications that are consistent, stable, and robust. While the development of individual modules may reflect years of research by imaging scientists, new customized workflows based on the new modules can be developed extremely fast. If a powerful, comprehensive application is difficult to learn and complicated to use, it will be unacceptable to most clinicians. Clinical image analysis tools must be intuitive and effective or they simply will not be used.
A study of the training possibilities of Araneus diadematus C1.

Kreuzspinnen verhielten sich verschieden, je nachdem ob eine tote Fliege mit Chininlosung, die durch eine vibrierende C-Stimmgabel in Bewegung gesetzt war, zuerst, oder eine Fliege in Glukoselosung, die durch eine C1-Stimmgabel vibrierte, als zweite ins Netz gereicht wurde. Durch Vertauschen der Faktoren konnte gezeigt werden, dass der Geschmack den auslosenden Reiz bildet. Wenn hingegen geschmacklose Glasperlen mit den Tonen kombiniert wurden, richteten sich die Spinnen in ihrem Verhalten nach der Schwingungsfrequenz. Diese Ergebnisse zeigen die Fahigkeit der Spinnen, sowohl zwischen verschiedenen Schwingungsfrequenzen zu unterscheiden, als auch ihr Verhalten der Erfahrung anzupassen.
Pronuclear Migration: No Attachment? No Union, but a Futile Cycle!

How do pronuclei migrate towards each other? The zebrafish futile cycle gene is shown to encode a maternally expressed membrane protein required for nuclear attachment and migration along the sperm aster.
Electro-mechanical characterization of structural supercapacitors

The paper presents electrical and mechanical properties of structural supercapacitors and discusses limitations associated with the approach taken for the electrical properties evaluation. The structural supercapacitors characterized in this work had the electrodes made of carbon fiber weave, separator made of several cellulose based products, and the solid electrolyte made as PEGDGE based polymer blend. The reported electrical properties include capacitance and leakage resistance; the former was measured using cyclic voltammetry. Mechanical properties have been evaluated thorough tensile and three point bending tests performed on structural supercapacitor coupons. The results indicate that the separator material plays an important role on the electrical as well as mechanical properties of the structural capacitor, and that Celgard 3501 used as separator leads to most benefits for both mechanical and electrical properties. Specific capacitance and leakage resistance as high as 1.4kF/m 3 and 380kΩ, respectively, were achieved. Two types of solid polymer electrolytes were used in fabrication, with one leading to higher and more consistent leakage resistance values at the expense of a slight decrease in specific capacitance when compared to the other SPE formulation. The ultimate tensile strength and modulus of elasticity of the developed power storage composite were evaluated at 466MPa and 18.9MPa, respectively. These values are 58% and 69% of the tensile strength and modulus of elasticity values measured for a single layer composite material made with the same type of carbon fiber and with a West System 105 epoxy instead of solid polymer electrolyte.
Noisy saltatory spike propagation: The breakdown of signal transmission due to channel noise

Noisy saltatory spike propagation along myelinated axons is studied within a stochastic Hodgkin-Huxley model. The intrinsic noise (whose strength is inversely proportional to the nodal membrane size) arising from fluctuations of the number of open ion channels influences the dynamics of the membrane potential in a node of Ranvier where the sodium ion channels are predominantly localized. The nodes of Ranvier are linearly coupled. As a measure for the signal propagation reliability, we focus on the ratio between the number of initiated spikes and the transmitted spikes. This work supplements our earlier study [A. Ochab-Marcinek, G. Schmid, I. Goychuk and P. Hanggi, Phys. Rev E 79, 011904 (2009)] towards stronger channel noise intensity and supra-threshold coupling. For strong supra-threshold coupling the transmission reliability decreases with increasing channel noise level until the causal relationship is completely lost and a breakdown of the spike propagation due to the intrinsic noise is observed.