cssi/SciSciGPT-SciSciNet huggingface dataset:
Endothelial attachment and plasmalemmal apposition in the transcellular movement of intravascular leukemic cells entering the myeloid parenchyma.

The plasmalemmal relationship between metastases-forming leukemia cells and myeloid sinus endothelium during the transmural passage of the leukemia cells has been studied in rat bone marrow. After the myeloid vascular system was freed from normal circulating blood cells, the bone marrow was perfused with a suspension of leukemia cells derived from an ascites tumor. The bone marrow was then fixed by perfusion with double aldehyde with and without the addition of tannic acid. Leukemia cells were seen adhering to the adluminal aspect of the sinus endothelium and in all stages of endothelial penetration. The penetration of the sinus wall was independent of endothelial junctions; i.e., the transmural passage into the myeloid parenchyma was transcellular. At these sites, there were restricted areas of close plasmalemmal appositions of the two cell types where the intraplasmalemmal space was reduced to 2.3 nm. This space was interrupted by electron densities of 5 nm diameter and spaced 9 nm center to center. These close plasmalemmal appositions extended over distances ranging from 150 nm to 200 nm. It is suggested on the basis of the structural similarity that these heptalaminar complexes of close plasmalemmal apposition represent the structural equivalent of gap junctions and may be sites of intercellular communication requisite for transmural passage. When tannic acid was added to the fixative, there were extended areas of apparent fusion of the plasmalemmas of the two cell types, at the sites both of adhesion and of endothelial penetration. This fusion was limited to the outer leaflets of the two plasmalemmas, resulting in a single pentalaminar complex. These pentalaminar complexes extended over decidedly longer distances than the presumed gap junctions seen in the nontannic-acid-fixed material. The tannic acid material did not show the heptalaminar gap junction type of plasmalemmal apposition. It is believed likely that the tannic-acid-induced pentalaminar complexes may incorporate the smaller heptalaminar ones. The factors underlying the plasmalemmal configurational differences between the tannic acid and non-tannic-acid material remain undetermined.
Effect of 1,25-Dihydroxyvitamin D3 on Phospholipid Metabolism in Cultured Bovine Parathyroid Cells*

There is evidence that 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] affects phospholipid metabolism of intestine, kidney, and bone. There are no such studies concerning the parathyroid gland, which is also a target tissue for 1,25-(OH)2D3. In this investigation we examined the effect of 1,25-(OH)2D3 on the incorporation of radiolabeled choline, inositol, serine, and ethanolamine into the phospholipids of cultured bovine parathyroid cells. Treatment with 10(-8) M 1,25-(OH)2D3 for 48 h caused a significant decrease in [14C]choline incorporation, although there were no differences in the incorporation of radiolabeled inositol, serine, or ethanolamine. Time-course and dose-response evaluations of the 1,25-(OH)2D3 effect revealed that the decrease in [14C]choline incorporation was seen within 12 h of incubation and occurred with as little as 10(-9) M, respectively. In contrast, neither 10(-7) M 25-hydroxyvitamin D3 nor 10(-7) M 24,25-(OH)2D3 caused significant changes in [14C]choline incorporation. When 5 X 10(-6) M cycloheximide was added to the medium, the inhibitory effect of 1,25-(OH)2D3 on [14C]choline incorporation was completely abolished. A significant decrease in phosphatidylcholine content was observed after treatment with 10(-8) M 1,25-(OH)2D3 for 96 h. 1,25-(OH)2D3 did not cause a dramatic change in the fatty acid composition of the phosphatidylcholine. The present studies demonstrate that in parathyroid cells 1,25-(OH)2D3 causes a decrease in [14C]choline incorporation, which could be due to a decrease in the synthesis of phosphatidylcholine or increased degradation. This effect is specific for 1,25-(OH)2D3 and requires new protein synthesis.
QTL analysis of horticultural traits differentiating the cultivated tomato from the closely related species Lycopersicon pimpinellifolium.

Molecular markers were used to map and characterize quantitative trait loci (QTLs) for several characters of agronomic and biological importance in an interspecific backcross of tomato. The parents of the cross were an elite processing inbred Lycopersicon esculentum cv ‘M82-1-7’ and the closely related red-fruited wild species L. pimpinellifolium (LA1589). A total of 257 BC1 plants were grown under field conditions in Ithaca, New York and scored for 19 quantitative traits. A genetic linkage map was constructed for the same population using 115 RFLP, 3 RAPD and 2 morphological markers that spanned 1,279 cM of the tomato genome with an average interval length of 10.7 cM. A minimum of 54 putatively significant QTLs (P 2.4) were detected for all characters with a range of 1–7 QTLs detected per character. Of the total 54 QTLs 11% had alleles with effects opposite to those predicted by the parental phenotypes. The percentage of phenotypic variation associated with single QTLs ranged from 4% to 47%. Multilocus analysis showed that the cumulative action of all QTLs detected for each trait accounted for 12–59% of the phenotypic variation. The difference in fruit weight was controlled largely by a single major QTL (fw2.2). Digenic epistasis was not evident. Several regions of the genome (including the region near sp on chromosome 6) showed effects on more than one trait. Implications for variety improvement and inferences about the domestication of the cultivated tomato are discussed.
X-ray bursts from MXB 1837+05.

Results are reported for SAS 3 observations of 22 bursts from the X-ray source designated MXB 1837+05. Assuming that all the bursts come from one source, the source position is determined to be right ascension (1950) 18 hr 37.9 min, declination (1950) 5 deg 4.2 min. Integrated burst intensities are listed along with ratios of counts in different energy channels, and it is found that there are significant variations in these ratios from burst to burst. The bursts are also shown to exhibit a variety of temporal structures (including double peaks) and changes in spectral hardness. No regularity was detected in the burst occurrence times during one observing period, but four bursts during another period seemed to recur at regular intervals of about 6.3 hr. It is concluded that an intensity-interval correlation similar to that for a rapid burster does not exist for MXB 1837+05 and that this source is probably identical with the relatively strong and steady source Ser X.1.
A Bacterial, Nitric Oxide Synthase from a Nocardia Species

Nitric oxide synthase (EC 1.14.23) was discovered in a Nocardia species. The bacterial nitric oxide synthase was purified as much as 380 fold by affinity chromatography over 2',5'-ADP-agarose. The partially purified enzyme required NADPH, O2, CA++, FAD, FMN, and tetrahydrobiopterin as cofactors in the conversion of L-arginine to L-citrulline and nitric oxide. The apparent Km for L-arginine was determined to be 8.2 microM, and the Vmax was 840 nmole NADPH consumed/min/mg protein. The enzyme was competetively inhibited by NG-nitro-arginine with an apparent Ki of 14.6 microM. The experimental evidence provides confirmation of the first microbial nitric oxide synthase in microorganisms.
Analysis of the RNA binding specificity of the human tap protein, a constitutive transport element-specific nuclear RNA export factor.

The human Tap protein has been proposed to mediate Mason Pfizer monkey virus constitutive transport element (CTE)-dependent nuclear RNA export and may also play a role in global mRNA export. Here, we have used in vivo assays, in both yeast and human cells, together with in vitro assays, to further characterize the RNA binding properties of Tap, which has been proposed to contain a novel leucine-rich RNA binding motif. Using the yeast three hybrid assay, we selected RNA molecules that retain Tap binding activity from a pool of randomized CTE sequences. The recovered RNA sequences differed only minimally from the wild-type CTE yet all displayed lower affinity for Tap both in vivo and in vitro. Analysis of the RNA export activity of the recovered CTE variants revealed that Tap affinity was highly predictive of CTE biological activity. Together, these observations provide additional evidence supporting the identification of Tap as the direct cofactor for CTE function and demonstrate that RNA binding by Tap is highly sequence specific.
Effect of DonJoy Ankle Ligament Protector and Aircast Sport-Stirrup Orthoses on Functional Performance

Clinicians often are faced with the task of selecting an ankle orthosis that will provide protection against ankle sprain injury and will not have a deleterious effect on functional performance. The purpose of this study was to compare the effects of the DonJoy® Ankle Ligament Protector (ALP) and the Aircast® Sport-Stirrup™ (AS) on three functional performance tasks: the 40-m sprint run, the figure-of-eight run, and the standing vertical jump. Subjects were eight males and eight females who reported no history of ankle injury during the 6 months prior to testing; neurological condition; lower extremity surgery or pathology; or cardiac, pulmonary, vascular, or balance problems. Each subject performed all functional tasks on the first test day with both ankles unbraced and with one randomly selected ankle braced with one of the two orthoses. Each subject returned for testing on a second day and performed all tasks with both ankles unbraced and with the other orthosis on the previously selected ankle. Subjec...
Violent Roots Lethal Violence in Two Counties in Early Statehood Washington

Was the American Western Frontier a violent place? While many agree with the popular Wild West conception, others argue for a Workaday, quiet version of the West. The Wild West/Workaday West debate is an important one because some argue that current levels of violence in the United States are a result of the Western history of violence. Unfortunately, establishing such a history of violence is difficult because of methodological issues. We propose here to address these methodological issues and participate in the Wild West/Workaday West debate. We examine two death records sources for Walla Walla and Spokane counties in Eastern Washington between 1903 and 1907. We find that the two Northwestern counties under study were more violent at the beginning of the 20th century than at the beginning of the 21st century, even though Walla Walla was significantly less violent than Spokane.
Informal Non-Kin Networks among Homeless Latino and African American Men: Form and Functions

This study explores the role social networks play in the daily survival of homeless Latino and African American men. Using a qualitative research design, the author examines how these men initiate, participate in, and maintain social networks, and how their networks function. The analysis compares two groups of Latinos (English and Spanish speakers) and African Americans. The findings support a view of homeless men as active, rational, and competent actors engaged in negotiating their social world. Participants rely on social networks composed of a hierarchy of casual and intimate affiliations. The networks of English-speaking Latinos and of African Americans facilitate their integration into a subculture of street life, whereas those of Spanish-speaking Latinos revolve around their struggles to find work, avoid deportation, and enlist the support of their countrymen. Holistic research approaches are required to advance an accurate understanding of the diverse nature of American homelessness and to instit...
Cryovolcanism on the Icy Satellites

Evidence of past cryovolcanism is widespread and extremely varied on the icy satellites. Some cryovolcanic landscapes, notably on Triton, are similar to many silicate volcanic terrains, including what appear to be volcanic rifts, calderas and solidified lava lakes, flow fields, breached cinder cones or stratovolcanoes, viscous lava domes, and sinuous rilles. Most other satellites have terrains that are different in the important respect that no obvious volcanoes are present. The preserved record of cryovolcanism generally is believed to have formed by eruptions of aqueous solutions and slurries. Even Triton's volcanic crust, which is covered by nitrogen-rich frost, is probably dominated by water ice. Nonpolar and weakly polar molecular liquids (mainly N2, CH4, CO, CO2, and Ar), may originate by decomposition of gas-clathrate hydrates and may have been erupted on some icy satellites, but without water these substances do not form rigid solids that are stable against sublimation or melting over geologic time. Triton's plumes, active at the time of Voyager 2's flyby, may consist of multicomponent nonpolar gas mixtures. The plumes may be volcanogenic fumaroles or geyserlike emissions powered by deep internal heating, and, thus, the plumes may be indicating an interior that is still cryomagmatically active; or Triton's plumes may be powered by solar heating of translucent ices very near the surface. The Uranian and Neptunian satellites Miranda, Ariel, and Triton have flow deposits that are hundreds to thousands of meters thick (implying highly viscous lavas); by contrast, the Jovian and Saturnian satellites generally have plains-forming deposits composed of relatively thin flows whose thicknesses have not been resolved in Voyager images (thus implying relatively low-viscosity lavas). One possible explanation for this inferred rheological distinction involves a difference in volatile composition of the Uranian and Neptunian satellites on one hand and of the Jovian and Saturnian satellites on the other hand. Perhaps the Jovian and Saturnian satellites tend to have relatively "clean" compositions with water ice as the main volatile (ammonia and water-soluble salts may also be present). The Uranian and Neptunian satellites may possess large amounts of a chemically unequilibrated comet-like volatile assemblage, including methanol, formaldehyde, and a host of other highly water- and ammonia-water-soluble constituents and gas clathrate hydrates. These two volatile mixtures would produce melts that differ enormously in viscosity The geomorphologic similarity in the products of volcanism on Earth and Triton may arise partly from a rheological similarity of the ammonia-water-methanol series of liquids and the silicate series ranging from basalt to dacite. An abundance of gas clathrate hydrates hypothesized to be contained by the satellites of Uranus and Neptune could contribute to evidence of explosive volcanism on those objects.
Conditionally linear models for non-homogeneous spatial random fields

We consider parsimonious representations of non-homogeneous spatial random fields. We focus on processes that can be represented as linear combinations of basis functions. As the basis functions are allowed to depend on unknown parameters, we identify such models with conditionally linear processes. We present a detailed description of an approach that uses discrete process convolutions with spatially varying, compactly supported kernels. We discuss the similarities and differences between this approach and the predictive Gaussian process approach. We also discuss the problem of obtaining decompositions of a spatial random field, as well as spatio-temporal extensions of our spatial models.
Kar3Vik1 uses a minus-end directed powerstroke for movement along microtubules.

We have used cryo-electron microscopy (cryo-EM) and helical averaging to examine the 3-D structure of the heterodimeric kinesin-14 Kar3Vik1 complexed to microtubules at a resolution of 2.5 nm. 3-D maps were obtained at key points in Kar3Vik1’s nucleotide hydrolysis cycle to gain insight into the mechanism that this motor uses for retrograde motility. In all states where Kar3Vik1 maintained a strong interaction with the microtubule, we found, as observed by cryo-EM, that the motor bound with one head domain while the second head extended outwards. 3-D reconstructions of Kar3Vik1-microtubule complexes revealed that in the nucleotide-free state, the motor’s coiled-coil stalk points toward the plus-end of the microtubule. In the ATP-state, the outer head is shown to undergo a large rotation that reorients the stalk ∼75° to point toward the microtubule minus-end. To determine which of the two heads binds to tubulin in each nucleotide state, we employed specific Nanogold®-labeling of Vik1. The resulting maps confirmed that in the nucleotide-free, ATP and ADP+Pi states, Kar3 maintains contact with the microtubule surface, while Vik1 extends away from the microtubule and tracks with the coiled-coil as it rotates towards the microtubule minus-end. While many previous investigations have focused on the mechanisms of homodimeric kinesins, this work presents the first comprehensive study of the powerstroke of a heterodimeric kinesin. The stalk rotation shown here for Kar3Vik1 is highly reminiscent of that reported for the homodimeric kinesin-14 Ncd, emphasizing the conservation of a mechanism for minus-end directed motility.
FURTHER STUDY OF AN ACTH-RELEASING PROTEIN FROM HYPOPHYSEAL PORTAL VESSEL PLASMA

Fraction III0 obtained from hypophyseal portal vessel plasma by the Cohn fractionation procedure possessed all of the ACTH-releasing activity of portal plasma. This fraction consisted of three major protein components with isoelectric points at pH 4.4, pH 5.1 and pH 6.6. Separation of the components of this fraction by starch column electrophoresis yielded an active peak with a mobility in veronal buffer (pH 8.6; µ = 0.l) of −1.91±.41 cm.2 volt−1 sec.−1 ×10−5. The activity associated with the proteins of fraction III0 was destroyed by incubation with trypsin and pepsin and by refluxing with 0.1 N NaOH. It was not destroyed by two hours of refluxing with 0.1 N HC1. Preliminary results indicated that the active substance could be dialyzcd awajr from the proteins in distilled water if the lyophilized portal plasma was dissolved in a Cohn Buffer at pH 6.9. This would suggest that this plasma protein serves in a transport role for an ACTH-releasing substance in portal vessel blood.
Conductor and vessel losses in bath cooled SMES systems

Several AC and DC loss sources are analyzed for superconductive magnetic energy storage (SMES) solenoids cooled in a bath of 1.8-K helium. The AC losses (eddy current losses) in the solenoid of the helium vessel and due to conductor stabilizer coupling loss are calculated for different charge or discharge sequences. The losses in the helium vessel are found for vessels both with and without an electric break. The analysis of DC loss for conductor joints takes into account several NbTi/Cu strands twisted around a high-purity aluminum stabilizer conductor. The resistance of the conductor joint depends on the electrical resistance of the bond between the strand and the aluminum and the distribution of joints staggered in position on the aluminum stabilizer.
An Electronic Safety Screening Process during Inpatient Computerized Physician Order Entry Improves the Efficiency of Magnetic Resonance Imaging Exams

Rationale and Objectives Delays between order and magnetic resonance (MR) exam often result when using the conventional paper-based MR safety screening process. The impact of an electronic MR safety screening process imbedded in a computerized physician order entry (CPOE) system was evaluated. Materials and Methods Retrospective chart review of 4 months of inpatient MR exam orders and reports was performed before and after implementation of electronic MR safety documentation. Time from order to MR exam completion, time from MR exam completion to final radiology report, and time from first order to final report were analyzed by exam anatomy. Length of stay (LOS) and date of service within the admission were also analyzed. Results We evaluated 1947 individual MR orders in 1549 patients under an institutional review board exemption and a waiver of informed consent. Implementation of the electronic safety screening process resulted in a significant decrease of 1.1 hours (95% confidence interval 1.0–1.3 hours) in the mean time between first order to final report and a nonsignificant decrease of 0.8 hour in the median time from first order to exam end. There was a 1-day reduction (P = .697) in the time from admission to the MR exam compared to the paper process. No significant change in LOS was found except in neurological intensive care patients imaged within the first 24 hours of their admission, where a mean 0.9-day decrease was found. Conclusion Benefits of an electronic process for MR safety screening include enabling inpatients to have decreased time to MR exams, thus enabling earlier diagnosis and treatment and reduced LOS.
Porous epoxies by reaction induced phase separation of removable alcohols: Control of spheroidal pore size by mass fraction, cure temperature, and reaction rate

Porous organic and inorganic materials with both random and controlled microstructures have utility in a variety of fields including catalysis, sensors, separations, optical platforms, tissue engineering, hydrogen storage, micro-electronics, medical diagnostics, as well as other applications. This work highlights a simple and general technique for tuning the pore size in crosslinking polymeric systems by adding a solvent poragen that phase separates during the curing process (reaction induced phase separation). The pore size can be controlled over large length scales ranging from microns to well below 100 nanometers. In this system an amine cured epoxy resin was reacted in the presence of the sacrificial poragen octadecanol, which is removed by vacuum-assisted evaporation once the epoxy components have reacted to form a solid, porous matrix. The importance of the present approach is based on the simplicity of the chemical formulation, the ease by which other epoxide or amine chemistries may be substituted for the two reactive components, and the control of pore size down to the nanometer scale by the addition of a small amount of catalyst. © 2010 Wiley Periodicals, Inc.† J Appl Polym Sci, 2010
Generalized Spatial Correlation and Speckle Analysis of laser speckle

We calculate the correlation of a laser speckle field using the Rayleigh-Sommerfeld-Smythe integral formula. The nonparaxial formulas for speckle sizes are new and the other results are consistent with the well-known solutions in the literature[1,2].
That earlier plague

The plague, appearing about A.D. 542, continued as a series of epidemics well into the seventh century and followed a pattern much like that of the fourteenth century Black Death. Just previously, the Byzantine Emperor Justinian (527–565) had recaptured North Africa from the Vandals and much of Italy from the Ostrogoths. The prospect of reestablishing the whole Roman Empire seemed good since conditions in the east were excellent and much of the west might welcome his armies. The plague interrupted and probably made impossible the fulfillment of that program. About as destructive as the later plague, it reduced the population 40–50 percent by the end of the century. This simplified culture by cutting down the size of the cities. Heavier mortality of smaller households injured the clergy and the more literate groups. The lighter losses in the dry areas tended to upset the balance between semi-nomadic and settled lands, Society was changed radically and upset emotionally. Burdened by increasing depression and loss of population, the Byzantine Empire had to reduce the size of its field armies. Not only was the offensive in the West abandoned after 565, but the southern defenses were so weakened that Islam, in the next century, tore away Egypt and Syria. The simpler conditions induced by the plague offered an ideal opportunity for the development and spread of Islam, particularly in the nomadic and semi-nomadic areas. In the west the threat of Frankish expansion weakened and localism increased. The general pattern of Greek, Arab, and German dominance was to persist for centuries.
U1 small nuclear RNA-like sequences in human high molecular weight RNA.

Summary Human U1 small nuclear RNA synthesis was shown earlier to be very sensitive to UV radiation. This led us to test for the possible presence of U1 RNA-like sequences in large RNAs. Human RNA was analyzed in gel blots hybridized with U1 DNA probes. A high molecular weight, heterodisperse RNA population was detected, which hybridizes both to a U1 RNA-coding region single-stranded DNA probe, and to a U1 gene fragment that contains only 6 nucleotides of flanking sequence. These large RNAs can be hybrid selected using immobilized U1 DNA, and have an average size of several kilobases. Additional observations support the claims that the high molecular weight RNA hybridization signal is not an aggregation artifact and that it is sequence specific.
Situational Repair of Replication Forks ROLES OF RecG AND RecA PROTEINS

Replication forks often stall or collapse when they encounter a DNA lesion. Fork regression is part of several major paths to the repair of stalled forks, allowing nonmutagenic bypass of the lesion. We have shown previously that Escherichia coli RecA protein can promote extensive regression of a forked DNA substrate that mimics a possible structure of a replication fork stalled at a leading strand lesion. Using electron microscopy and gel electrophoresis, we demonstrate that another protein, E. coli RecG helicase, promotes extensive fork regression in the same system. The RecG-catalyzed fork regression is very efficient and faster than the RecA-promoted reaction (up to 240 bp s(-1)), despite very limited processivity of the RecG protein. The reaction is dependent upon ATP hydrolysis and is stimulated by single-stranded binding protein. The RecA- and RecG-promoted reactions are not synergistic. In fact, RecG functions poorly under the conditions optimal for the RecA reaction, and vice versa. When both RecA and RecG proteins are incubated with the DNA substrate, high RecG concentrations inhibit the RecA protein-promoted fork regression. The very different reaction profiles may reflect a situational application of these proteins to the rescue of stalled replication forks in vivo.
REEVALUATION OF THE GAS-PHASE VALENCE PHOTOELECTRON SPECTRA OF OCTAETHYLPORPHYRIN AND TETRAPHENYLPORPHYRIN

Gas-phase valence photoelectron spectra are reported for 2,3,7,8,12,13,17,18-octaethylporphyrin (OEPH{sub 2}) and 5,10,15,20-tetraphenylporphyrin (TPPH{sub 2}). Comparison of spectra collected with He I and He II sources give an empirical assignment of the relative order of the low-energy {sup 2}A{sub u} and {sup 2}B{sub 1u} ion states in the gas phase. For OEPH{sub 2}, the first ionization at 6.24 eV is assigned to the {sub 2}A{sub u} ion state, with the {sup 2}B{sub 1u} ionization located 0.25 eV to higher energy. The photoelectron spectrum reported here is quite different from the previously reported spectrum of OEPH{sub 2}. The first ionization of TPPH{sub 2} is assigned to the {sup 2}B{sub 1u} ion state, with the {sup 2}A{sub u} ionization 0.27 eV to higher energy. The reversal of the ordering of the first two ionizations of OEPH{sub 2} and TPPH{sub 2} is due to the different site of the substituents and the different nodal properties of the porphyrin orbitals.
Challenges and Recommendations to Enforcement of Alcohol Policies on College Campuses: An Administrator's Perspective

Objective: The purpose of this study was to examine challenges and recommendations (identified by college administrators) to enforcing alcohol policies implemented at colleges in the southeastern United States. Methods: Telephone interviews were conducted with 71 individuals at 21 institutions. Results: Common challenges included inconsistent enforcement, mixed messages received by students, and students’ attitudes toward alcohol use. The most common recommendations were ensuring a comprehensive approach, collaboration with members of the community, and enhanced alcohol education.
Discovery of DampedLyα Systems at Redshifts Less than 1.65 and Results on Their Incidence and Cosmological Mass Density

We present results from an efficient, nontraditional survey to discover damped Lyα (DLA) absorption systems with neutral hydrogen column densities N ≥ 2 × 1020 atoms cm-2 and redshifts z 0.5 A are DLA systems. (2) The incidence of DLA systems per unit redshift, nDLA, decreases as a function of decreasing redshift. The low-redshift data are consistent with the larger incidence of DLA systems seen at high redshift and the inferred low incidence for DLA at z = 0 derived from 21 cm observations of gas-rich spirals. However, the errors in our determination are large enough that it is not clear if the decrease per comoving volume begins to be significant at z ≈ 2 or possibly does not set in until z ≈ 0.5. (3) On the other hand, the cosmological mass density of neutral gas in low-redshift DLA absorbers, ΩDLA, is observed to be comparable to that observed at high redshift. In particular, there is no observed trend that would indicate that ΩDLA at low redshift is approaching the value at z = 0, which is a factor of ≈4-6.5 lower than ΩDLA. (4) The low-redshift DLA absorbers exhibit a larger fraction of very high column density systems in comparison to determinations both at high redshift and at z = 0. In addition, at no redshift is the column density distribution of DLA absorbers observed to fall off in proportion to ~N with increasing column density, a trend that is theoretically predicted for disklike systems. We discuss this and other mounting evidence that DLA absorption arises not solely in luminous disks but in a mixture of galaxy types. Although we have doubled the sample of confirmed low-redshift DLA systems, we are still confronted with the statistics of small numbers. As a result, the errors in the low-redshift determinations of nDLA and ΩDLA are substantial. Therefore, aside from the above evolutionary trends, we also discuss associated limitations caused by small-number statistics and the robustness of our results. In addition, we note concerns due to gravitational lensing bias, reliance on the Mg II statistics, dust obscuration, and the sensitivity of local H I 21 cm emission surveys.
Dispersion of alkylammonium montmorillonites in organic liquids

Abstract The relative dispersing power of a series of liquids for alkylammonium montmorillonites has been measured by determining the change in optical density with time in a process which was shown to be sedimentation and not flocculation. Although a limiting degree of dispersion is reached in most liquids for a given level of mechanical agitation, no evidence was found for existence in this case of a reversible equilibrium involving mechanical agitation as one of the variables of state. There is no simple correlation between chemical constitution of liquids and their dispersing power for the organophilic clays studied.
Molecular-dynamics simulations of energetic C60 impacts on (2×1)-(100) silicon

Single impacts of energetic C60 clusters on (2×1)-(100) silicon substrates are studied by molecular-dynamics simulations. The role of impact energies and internal cluster energy are investigated in detail. Six different energy regimes can be identified at the end of the ballistic phase: At thermal energies below 20 eV the fullerene cages undergo elastic deformation, while impinging on the surface, and are mostly chemisorpted on top of the (2×1)-dimer rows. Between 20 and 100 eV the cage structure is preserved after the collision, but the cluster comes to rest within a few monolayers of the silicon surface. At energies of 100–500 eV the cluster partially decomposes and small coherent carbon caps are embedded in the surface. At higher energies up to 1.5 keV complete decomposition of the fullerene cluster occurs and an amorphous zone is formed in the subsurface area. At energies greater than approximately 1.5 keV craters form and above 6 keV sputtering becomes significant. In all cases the substrate temperature is of minor influence on the final result, but the projectile temperature is important for impacts at lower energies (<1.5 keV). For high energy impacts the ballistics resemble that of single atom impacts. Nearly 1:1 stoichiometry is obtained for impact energies around 1 keV. These results reveal an interesting possibility for controlled implantation of C in Si at high local concentrations, which might allow the formation of silicon carbide.
The Influence of Chemical Additives on the Heat Resistance of Salmonella typhimurium in Liquid Whole Egg

SUMMARY The heat resistance of Salmonella typhimurium in liquid whole egg at pH 5.5 and 55°C was reduced significantly by a number of chemical additives. Of these, the most effective were β-propiolactone, ethylene oxide, and butadiene dioxide. Additional advantages of ethylene oxide and β-propiolactone were the elimination of S. typhimurium from heavily inoculated whole-egg slurry during storage at 0°C and a markedly increased lag phase of growth of the test organism in egg incubated at 30°C. Butadiene dioxide, although not tested at 0°C, was most effective in reducing heat resistance at pH 5.5 and 55° C, and also greatly increased the lag phase of the test organism at 30° C. Unfortunately, this latter compound is carcinogenic to mice. Acetic or lactic acid, used to lower the pH of liquid whole eggs, decreased the heat resistance of S. typhimurium more effectively than did hydrochloric acid, especially at pH 5.5 arid 6.0. Formic and propionic acids also were more effective than HCl when all were tested at pH 5.5. Differences in degree of dissociation between hydrochloric and the organic acids are thought to account, in large measure, for these observations.
Nuisance or nimby? Land application of biosolids

The land application of biosolids generates much controversy, particularly among those residing near the land application site. However, land application is a generally accepted agricultural practice. The United States Environmental Protection Agency supports proper land application of biosolids, but much scientific uncertainty still exists. In the United States, local, state and federal officials struggle over the question of which level of government should regulate biosolids. The present state of regulation in the United States is summarized. Finally, the paper analyzes land application of biosolids against traditional nuisance standards and discusses whether land application of biosolids is a nuisance or not.
The Effects of Napping on Cognitive Function in Preschoolers

Objective: To determine the relationship between napping and cognitive function in preschool- aged children. Methods: Daytime napping, nighttime sleep, and cognitive function were assessed in 59 typically developing children aged 3 to 5 years, who were enrolled in full-time childcare. Participants wore an actigraphy watch for 7 days to measure sleep and napping patterns and completed neuropsychological testing emphasizing attention, response control, and vocabulary. Parents of participants completed behavior ratings and sleep logs during the study. Sleep/wake cycles were scored with the Sadeh algorithm. Results: Children who napped more on weekdays were also more likely to nap during weekends. Weekday napping and nighttime sleep were inversely correlated, such that those who napped more slept less at night, although total weekday sleep remained relatively constant. Weekday napping was significantly (negatively) correlated with vocabulary and auditory attention span, and weekday nighttime sleep was positively correlated with vocab- ulary. Nighttime sleep was also significantly negatively correlated with performance, such that those who slept less at night made more impulsive errors on a computerized go/no-go test. Conclusions: Daytime napping is actually negatively correlated with neurocognitive function in preschoolers. Nighttime sleep seems to be more critical for development of cognitive performance. Cessation of napping may serve as a develop- mental milestone of brain maturation. Children who nap less do not appear to be sleep deprived, especially if they compensate with increased nighttime sleep. An alternative explanation is that children who sleep less at night are sleep deprived and require a nap. A randomized trial of nap restriction would be the next step in understanding the relationship between napping and neurocognitive performance. (J Dev Behav Pediatr 32:90-97, 2011) Index terms: childhood, attention, sleep, cognition, actigraphy, preschool.
Perceived Gaze Direction and the Processing of Facial Displays of Emotion

There is good reason to believe that gaze direction and facial displays of emotion share an information value as signals of approach or avoidance. The combination of these cues in the analysis of social communication, however, has been a virtually neglected area of inquiry. Two studies were conducted to test the prediction that direct gaze would facilitate the processing of facially communicated approach-oriented emotions (e.g., anger and joy), whereas averted gaze would facilitate the processing of facially communicated avoidance-oriented emotions (e.g., fear and sadness). The results of both studies confirmed the central hypothesis and suggest that gaze direction and facial expression are combined in the processing of emotionally relevant facial information.
Activists and Conflict Extension in American Party Politics

Party activists have played a leading role in “conflict extension”—the polarization of the parties along multiple issue dimensions—in contemporary American politics. We argue that open nomination systems and the ambitious politicians competing within those systems encourage activists with extreme views on a variety of issue dimensions to become involved in party politics, thus motivating candidates to take noncentrist positions on a range of issues. Once that happens, continuing activists with strong partisan commitments bring their views into line with the new candidate agendas, thus extending the domain of interparty conflict. Using cross-sectional and panel surveys of national convention delegates, we find clear evidence for conflict extension among party activists, evidence tentatively suggesting a leading role for activists in partisan conflict extension more generally, and strong support for our argument about change among continuing activists. Issue conversion among activists has contributed substantially to conflict extension and party commitment has played a key role in motivating that conversion.
A new type of atomic force microscope based on chaotic motions

Abstract Local flow variation (LFV) method of non-linear time series analysis is applied to develop a chaotic motion-based atomic force microscope (AFM). The method is validated by analyzing time series from a simple numerical model of a tapping mode AFM. For both calibration and measurement procedures the simulated motions of the AFM are nominally chaotic. However, the distance between a tip of the AFM and a sample surface is still measured accurately. The LFV approach is independent of any particular model of the system and is expected to be applicable to other micro-electro-mechanical system sensors where chaotic motions are observed or can be introduced.
Variable structure and nonlinear adaptive flight path control

Treats the question of inertial trajectory control of aircraft in the three-dimensional space. The control system is decomposed into a variable structure outer-loop and an adaptive inner-loop. The outer-loop feedback control system accomplishes (x, y, z) position trajectory and sideslip angle control using the derivative of thrust and three angular velocity components (p, q, r) as virtual control inputs. Then an adaptive inner feedback loop is designed, which produces the desired angular rotations of aircraft using aileron, elevator, and rudder control surfaces to complete the maneuver. These results are applied to a simplified FA-18 model. Simulation results are presented which show that in the closed-loop system asymptotic trajectory control is accomplished in spite of uncertainties in the model at different flight conditions.
Circuit techniques for wireless bioelectrical interfaces

Recent advances in integrated circuit technology scaling, analog circuitry, and wireless communication have created the possibility for complex low noise, low power wireless instrumentation to be deployed in previously impossible scenarios, particularly in the realm of wireless sensing for biology research and biomedical applications. The generation of portable, autonomous devices made possible by these improvements will allow, for example, unobtrusive long-term health monitoring by way of fully implantable clinical diagnostic systems. This paper presents some achievements made to this end, and describes the circuit design techniques and system architectures used to realize low power wireless bioelectrical interfaces.
On the voxel size and magnetic field strength dependence of spectral resolution in magnetic resonance spectroscopy

While the inherent low sensitivity of in vivo MR spectroscopy motivated a trend towards higher magnetic fields, B(0), it has since become apparent that this increase does not seem to translate into the anticipated improvement in spectral resolution. This is attributed to the decrease of the transverse relaxation time, T(2)*, in vivo due to macro- and mesoscopic tissue susceptibility. Using spectral contrast-to-noise ratio (SCNR) arguments, we show that if in biological systems the linewidth (on the frequency scale) increases linearly with the field, the spectral resolution (in parts per million) improves approximately as the fifth-root of B(0) for chemically shifted lines and decreases as about B(0)(4/5) (in hertz) for a structure of J-coupled multiplets. It is also shown that for any given B(0) there is a unique voxel size that is optimal in spectral resolution, linking the spectral and spatial resolutions. Since in practical applications the spatial resolution may be dictated by the target anatomy, nomograms to determine the B(0) required to achieve the desired spectral resolution at that voxel size are presented. More generally, the scaling of the nomograms to determine the achievable spectral and spatial resolutions at any given field is described.
Health disparities and direct-to-consumer prescription drug advertising: a content analysis of targeted magazine genres, 1992-2002.

Health disparities exist in the United States based on race, gender, and socioeconomic status. One way to alleviate some of the disparities regarding certain diseases or conditions is to increase awareness among populations most affected. Physicians have suggested that direct-to-consumer advertising (DTCA) of prescription drugs could play a role in awareness. Social identity theory suggests that individuals are likely to attend messages if they can identify, often based on race or gender, with people portrayed in the messages. This study analyzed DTCA in 11 years of Black, women's, news, and entertainment magazines to determine whether models in the ads targeted specific populations. Black magazines were more likely to contain ads featuring Black models only than were other genres, which had more DTCA picturing White models only. Health conditions the drugs were intended for varied by genre and over time, with STD drugs appearing primarily in Black magazines, and DTCA for heart disease not published in Bl...
Concepts for mobile programming

Computer Science departments are beginning to recognize the importance of offering courses in mobile application development. This paper discusses underlying concepts that should be addressed in these courses. These concepts are grouped into six categories: User interface, Device cooperation, Hardware issues, Data handling, Application interaction, and Programming issues.
Electrical detection of nucleic acid amplification using an on-chip quasi-reference electrode and a PVC REFET.

Electrical detection of nucleic acid amplification through pH changes associated with nucleotide addition enables miniaturization, greater portability of testing apparatus, and reduced costs. However, current ion-sensitive field effect transistor methods for sensing nucleic acid amplification rely on establishing the fluid gate potential with a bulky, difficult to microfabricate reference electrode that limits the potential for massively parallel reaction detection. Here we demonstrate a novel method of utilizing a microfabricated solid-state quasi-reference electrode (QRE) paired with a pH-insensitive reference field effect transistor (REFET) for detection of real-time pH changes. The end result is a 0.18 μm, silicon-on-insulator, foundry-fabricated sensor that utilizes a platinum QRE to establish a pH-sensitive fluid gate potential and a PVC membrane REFET to enable pH detection of loop mediated isothermal amplification (LAMP). This technique is highly amendable to commercial scale-up, reduces the packa...
Topics in the Development of Aggression, Peer Relations, and Sex Differences

This chapter continues the themes developed in the previous chapters by applying these ideas to some of the central issues in the area of social development. In particular, I will attempt to place these data in a cross-cultural and historical context, a context shaped by the sociobiologically predicted central tendencies described previously. Moreover, as in previous chapters, I will emphasize the environment-expectant affective systems and their roles in the socialization of behavior, as well as temperament as a ubiquitously important set of epigenetic rules that bias social behavior in a variety of domains. I will not attempt to review all of the research in the areas of aggression, peer relations, and sex differences, but instead select some of the central issues where an evolutionary analysis seems most appropriate and where there is already sufficient research to enable an assessment of this theoretical perspective.
Spills of fuel oil #6 and Orimulsion can have indistinguishable effects on the benthic meiofauna

Fuel oil #6 is used for the production of electrical power in the United States. Orimulsion® is being considered as an alternative fuel, but its value and risk compared to fuel oil #6 need to be assessed. Our study examined the relative impact of accidental spills of the two hydrocarbons on the meiofaunal community. To do so, we maintained microcosms of the shallow, sandy, subtidal environment for three months. Treatment microcosms received a single application of hydrocarbon-coated sand. As indicators of effect, we used copepod and nematode abundance and copepod species diversity, sex ratio, fecundity, age structure, and neutral-lipid content. A comparison of the hydrocarbon treatments showed no significant differences. The tests had adequate power to detect ecologically significant changes. Our results indicate that a spill of Orimulsion would have approximately the same impact as a spill of fuel oil #6 on the meiofauna.