cssi/SciSciGPT-SciSciNet huggingface dataset:
Synthesis of a New Ternary Nitride, Fe4W2N, with a Uniqueη-Carbide Structure

Abstract The structure of a new ternary nitride, Fe 4 W 2 N, prepared using a metal-organic precursor synthesis route, has been determined by Rietveld refinement of the monochromatic X-ray powder diffraction data. The compound crystallizes in a cubic, η -carbide structure, space group Fd 3 m (227), with Z =16 and a lattice parameter of a =11.0810(9) A. The refinement converged with R wp =0.1273, R p =0.0709, R I =0.0478, and S =1.72. The compound is isostructural with Fe 4 W 2 C, the ideal structure consisting of eight octahedra of metal atoms, a random mixture of which one-third are iron and two-thirds are tungsten, centered on a diamond cubic lattice and eight regular tetrahedra of iron atoms centered on a second diamond cubic lattice that interpenetrates the first through a 1 2 , 1 2 , 1 2 unit cell translation. Sixteen additional iron atoms are tetrahedrally coordinated around the iron tetrahedra and sixteen nitrogen atoms surround the metal octahedra in tetrahedral coordination.
MD Simulations of the dsRBP DGCR8 Reveal Correlated Motions that May Aid pri-miRNA Binding

Over the past decade, microRNAs (miRNAs) have been shown to affect gene regulation by basepairing with messenger RNA, and their misregulation has been directly linked with cancer. DGCR8, a protein that contains two dsRNA-binding domains (dsRBDs) in tandem, is vital for nuclear maturation of primary miRNAs (pri-miRNAs) in connection with the RNase III enzyme Drosha. The crystal structure of the DGCR8 Core (493–720) shows a unique, well-ordered structure of the linker region between the two dsRBDs that differs from the flexible linker connecting the two dsRBDs in the antiviral response protein, PKR. To better understand the interfacial interactions between the two dsRBDs, we ran extensive MD simulations of isolated dsRBDs (505–583 and 614–691) and the Core. The simulations reveal correlated reorientations of the two domains relative to one another, with the well-ordered linker and C-terminus serving as a pivot. The results demonstrate that motions at the domain interface dynamically impact the conformation of the RNA-binding surface and may provide an adaptive separation distance that is necessary to allow interactions with a variety of different pri-miRNAs with heterogeneous structures. These results thus provide an entry point for further in vitro studies of the potentially unique RNA-binding mode of DGCR8.
In vivo to in vitro transfer of trout spleen sections for early analysis of the immune response

To determine the earliest time after in vivo immunisation that the spleen could be excised and held in vitro to detect an immune response, lake trout ( Salvelinus namaycush ) were exposed to DNP-Ficoll or Yersinia ruckeri O antigen administered by intraperitoneal injection or by bath. The spleens were excised from the fish at selected times after immunisation, placed in vitro and held in tissue culture media at 14°C until 10 days after the in vivo immunisation. They then were analysed for an immune response by counting the numbers of plaqueforming cells (PFC). PFC were first detected in samples taken 3 days after injection with either antigen. With bath immunisation, however, PFC were first seen 6 days post-immunisation when using the Y. ruckeri O antigen and no PFC above background levels appeared in fish bathed in the DNP-Ficoll solution. On day 10 after immunisation, the spleens taken directly from immunised fish always produced more PFC than when the spleens were taken through in vitro culture. A unique feature of this method, is that an immune response to an antigen may be detected by excising the spleen and holding it in in vitro culture without necessarily holding the fish for long periods of time after antigen injection or bath. This technique also adds more information on how rapidly the bacterins or antigens are processed by fish to initiate an immune response.
Applications Of Computer Vision

Computers play a role in everyone's life in one way or another. Ever since Turing postulated his, by now well known, "Turing test," there has been an enormous increase in the use of machines to do more than mere computation. Within the last five years or so there has been spurt in the use of machines to perform assembly line tasks. In particular welding, painting, assembly inspection, manufacturing etc. To quite an extent these various attempts are a blindfold approach to manufacturing. In other words they do not use Computer Vision. This paper is an attempt at explaining some of the results, the problems and shortcomings of using Computer Vision in the real world.© (1976) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Structural, spectral and thermal studies of N-2-(4-picolyl)- and N-2-(6-picolyl)-N′-(2-chlorophenyl)thioureas and N-2-(6-picolyl)-N′-(2-bromophenyl)thiourea

Abstract N -2-(4-picolyl)- N ′-2-chlorophenylthiourea, 4PicTu2Cl, monoclinic, P 2 1 / c , a =10.068(5), b =11.715(2), c=11.185(6) A , β =96.88(4)°, V=1309.8(2) A 3 and Z =4; N -2-(6-picolyl)- N ′-2-chlorophenylthiourea, 6PicTu2Cl, triclinic, P -1, a =7.4250(8), b =7.5690(16), c=12.664(3) A , α =105.706(17), β =103.181(13), γ =90.063(13)°, V=665.6(2) A 3 and Z =2 and N -2-(6-picolyl)- N ′-2-bromophenylthiourea, 6PicTu2Br, triclinic, P -1, a =7.512(4), b =7.535(6), c=12.575(4) A , a =103.14(3), β =105.67(3), γ =90.28(4)°, V=665.7(2) A 3 and Z =2. The intramolecular hydrogen bonding between N′H and the pyridine nitrogen and intermolecular hydrogen bonding involving the thione sulfur and the NH hydrogen, as well as the planarity of the molecules, are affected by the position of the methyl substituent on the pyridine ring. The enthalpies of fusion and melting points of these thioureas are also affected. 1 H NMR studies in CDCl 3 show the NH′ hydrogen resonance considerably downfield from other resonances in their spectra.
Application of kinetic model to in vitro percutaneous permeation of drugs

Kinetic model using inter-compartmental rate constants, for permeation of drug across stratum corneum (k1), for permeation across viable tissue layer of epidermis (k2), and for back transfer of drug from viable tissue layer into the stratum corneum (k3), was applied to in vitro percutaneous permeation process. Permeation data of four drugs, propranolol (PR), triamcinolone acetonide (TA), physostigmine (PHY), and tetrahydroaminoacridine (THA), previously studied across two skin membranes, hairless mouse skin (HMS) and human cadaver skin (HCS) were fitted to the permeation equation based on the kinetic model to obtain optimized values of the rate constants. The permeation profiles were also analyzed by the lag time method to estimate steady state flux (Jss), lag time (Tlag), diffusion coefficient (D) and Skin/donor-phase partition coefficient (Km). The D and Km were used to regenerate the entire permeation profile (pre-steady and steady states) using equation based on Fick's laws of diffusion. The kinetic and diffusion models were compared by fits of the observed data to the model predicted values by linear regression, and obtaining R2 and sum of squared deviations (SSD). Permeation data for all drugs across HMS or HCS, with or without the presence of permeation enhancer, were described very well by the kinetic model (R2 > 0.99), and the SSD's were smaller than that for the diffusion model except for THA. The rate of drug permeation across stratum corneum, k0 (k1 X Dose, amount of drug applied/cm2 of skin in the donor phase) was similar to Jss as expected from the kinetic model. Diffusion coefficient of drug in the viable tissue (Dvt) ranged from 0.003–0.23 × 10−7 cm2/s, similar to diffusion coefficient of similar sized molecules in protein gel as would be expected. Also, Dvt was four orders of magnitude greater than D, the diffusion coefficient across stratum corneum, confirming stratum corneum to be the rate limiting barrier in the percutaneous permeation of the drugs studied. k3 for all drugs were negligible indicating that no back diffusion of drug from viable tissue into the stratum corneum was occurring under the sink condition following infinite dose application. Also, except TA, none of the drug studied was lipophilic enough to be retained by the stratum corneum. Therefore, k3 should not be used in the kinetic model for in vitro percutaneous permeation. For the PR 27-h, TA control and TA with 2% propylene glycol (PG) pretreatment experiments, the experiment duration was less than three Tlag and steady state was not achieved, resulting in inaccurate estimates of D and Km and, hence, the regenerated profiles based on diffusion model did not describe the data well. However, kinetic model described these data also very well and SSD's were significantly smaller (P = 0.05) than that for the diffusion model based regenerated profiles. The kinetic model is an alternative to diffusion model to describe the percutaneous permeation process, and the results presented here demonstrate the usefulness of the kinetic approach.
Comparative evaluation of apoptosis induced by Shiga toxin 1 and/or lipopolysaccharides in human monocytic and macrophage-like cells

The enteric pathogens Shigella dysenteriae serotype 1 and Shiga toxin-producing Escherichia coli share the property of expressing the structurally and functionally related cytotoxins that comprise the Shiga toxin (Stx) family. Stx-producing bacteria are causative agents of bloody diarrheal diseases that may progress to life threatening complications involving the destruction of blood vessels in the kidneys and the central nervous system (CNS). The precise mechanisms of toxin transport across the gut epithelial barrier, and the role of innate immunity in the development of systemic complications, remain to be fully characterized. Earlier studies suggested that Stxs and lipopolysaccharides (LPS) induce the expression of proinflammatory cytokines from differentiated (macrophage-like) THP-1 cells. These cytokines may exacerbate vascular damage by up-regulating the expression of toxin receptors on endothelial cells. Purified Stxs have also been shown to induce apoptosis of epithelial and endothelial cells in vitro, but a comparative evaluation of Stx-induced apoptosis of monocytes and macrophages has not been reported. We used FACS, TUNEL, and DNA laddering analyses to show that Shiga toxin-1 (Stx1) and LPS induce apoptosis in undifferentiated and differentiated THP-1 cells, although the kinetics and extent of apoptosis induction differ between monocytic and macrophage-like cells. Stx1-induced apoptosis is A-subunit-dependent. Stx1 and LPS trigger DNA fragmentation and caspase-3 activation, as evidenced by the cleavage of poly(ADP-ribose) polymerase (PARP). Induction of apoptosis in response to Stx1 and/or LPS treatment occurs without the widespread transcriptional activation of apoptosis-related genes. Finally, we present a model of the role of macrophages and monocytes in the pathogenesis of disease caused by Stxs.
Are Incidental Findings on Brain Magnetic Resonance Images in Children Merely Incidental

The purpose of this study was to test the hypothesis that children with developmental delay without regression of unknown etiology are more likely to have intracranial incidental findings than are children with autistic spectrum disorder or children with normal development. Of 771 patients with magnetic resonance images, 363 (47.1%) patients had developmental delay, 55 (7.1%) had autistic spectrum disorders, and 353 (45.8%) were developmentally normal. Developmentally delayed children were more likely than those with normal development (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.3-2.5; P < .001) or those with autistic spectrum disorder (OR, 2.1; 95% CI, 1.1-4.1; P = .019) to have an intracranial incidental finding. We report a higher prevalence of intracranial incidental findings in children with developmental delay as compared with those children with normal development. Future study should confirm whether the result of this study is merely incidental or truly related to a subgroup of children...
Molecular basis of parathyroid hormone receptor signaling and trafficking: a family B GPCR paradigm.

The parathyroid hormone (PTH) receptor type 1 (PTHR), a G protein-coupled receptor (GPCR), transmits signals to two hormone systems—PTH, endocrine and homeostatic, and PTH-related peptide (PTHrP), paracrine—to regulate different biological processes. PTHR responds to these hormonal stimuli by activating heterotrimeric G proteins, such as GS that stimulates cAMP production. It was thought that the PTHR, as for all other GPCRs, is only active and signals through G proteins on the cell membrane, and internalizes into a cell to be desensitized and eventually degraded or recycled. Recent studies with cultured cell and animal models reveal a new pathway that involves sustained cAMP signaling from intracellular domains. Not only do these studies challenge the paradigm that cAMP production triggered by activated GPCRs originates exclusively at the cell membrane but they also advance a comprehensive model to account for the functional differences between PTH and PTHrP acting through the same receptor.
Quo Vadimus: computer science in a decade

A panel discussion was held during the third biennial meeting of chairmen of Ph.D.-granting computer science departments in June, 1978 at Snowbird, Utah, a meeting sponsored by the Computer Science Board. Invitees from industry and government were also present. A report was prepared from tapes made of the discussion (Department of Computer Science, Carnegie-Mellon University: Report #CMU-CS-80-127, June 1980). It contained all the prepared statements of the panelists, lightly edited, and the panelists' discussion in its entirety. A selection of the audience discussion was also included, rather heavily edited. The following presentation is derived from that report.
Direct evidence of hydrogen generation from the reaction of water with FeAl

One of the most important findings in the recent study of deformation and fracture in ordered intermetallics is that many intermetallic alloys with high crystal symmetries (such as L1{sub 2} and B2) are intrinsically quite ductile at ambient temperatures, and that their commonly observed low ductility and brittle fracture are caused mainly by extrinsic factors. Environmental embrittlement has been identified as a major extrinsic factor that embrittles many intermetallic alloys. In this case, the alloys showed brittle fracture and low ductilities when tested in moist air, but they exhibited distinctly high ductilities when tested in high-vacuum or dry-oxygen environments. In order to have a mechanistic understanding of moisture-induced hydrogen embrittlement, it is essential to have a direct measurement of trapped hydrogen atoms with position resolution. In this study, the authors try to develop a laser desorption mass spectrometric method to measure hydrogen atoms in a position-sensitive way. They also compare the amount of trapped hydrogen, with and without exposure to water, for FeAl containing 35.8 at. % Al.
A Framework for Supporting Tree-Like Indexes on the Chord Overlay

With the explosive growth of data, to support efficient data management including queries and updates, the database system is expected to provide tree-like indexes, such as R-tree, M-tree, B+-tree, according to different types of data. In the distributed environment, the indexes have to be scattered across the compute nodes to improve reliability and scalability. Indexes can speed up queries, but they incur maintenance cost when updates occur. In the distributed environment, each compute node maintains a subset of an index tree, so keeping the communication cost small is more crucial, or else it occupies lots of network bandwidth and the scalability and availability of the database system are affected. Further, to achieve the reliability and scalability for queries, several replicas of the index are needed, but keeping the replicas consistent is not straightforward. In this paper, we propose a framework supporting tree-like indexes, based on Chord overlay, which is a popular P2P structure. The framework dynamically tunes the number of replicas of index to balance the query cost and the update cost. Several techniques are designed to improve the efficiency of updates without the cost of performance of the queries. We implement M-tree and R-tree in our framework, and extensive experiments on real- life and synthetic datasets verify the efficiency and scalability of our framework.
Effect of Diet on Experimental Hypertension and on the Development of Polyarteritis Nodosa in Rats

Rats with experimental renal hypertension were fed various diets differing in sodium and protein content. Marked prolongation of life was achieved by rice diet. Polyarteritis nodosa developed, as a result of the experimental procedures, in 23.5 per cent of the animals. Its incidence was closely correlated to sodium ingestion: 4 per cent in rats on low sodium intake, 36 per cent in rats on normal or slightly higher sodium intake. Protein intake showed no effect on incidence of polyarteritis but distinct effect on survival time. Except for one rat where a sarcoma destroyed almost all kidney tissue, no animal on rice diet developed polyarteritis nodosa.
Call to action: simplifying voice tree design

Call to Action is an open-source web platform for creating telephone-based services such as hotlines, voice petitions and phone blogging platforms being developed at MIT's Center for Civic Media. It seeks to simplify the design and deployment process for non-technical users, such as community groups. This poster will illustrate the platform's GUI, methodology, typical use cases and future development prospects.
Induction of apoptosis in IL-3–dependent hematopoietic cell lines by guanine nucleotide depletion

Inosine 5'-monophosphate dehydrogenase (IMPDH) is a rate-limiting enzyme that catalyzes the conversion of IMP to xanthosine monophosphate (XMP) at the branch point of purine nucleotide biosynthesis, leading to the generation of guanine nucleotides. Inhibition of IMPDH results in the depletion of guanine nucleotides, prevents cell growth by G1 arrest, and induces cell differentiation in a cell-type-specific manner. The molecular and sensing mechanisms underlying these effects are not clear. We have examined the induction of apoptosis by mycophenolic acid (MPA), a specific IMPDH inhibitor, in interleukin-3 (IL-3)-dependent murine hematopoietic cell lines. MPA treatment, at clinically relevant doses, caused apoptosis in 32D myeloid cells and in FL5.12 and BaF3 pre-B cells in the ongoing presence of IL-3. Apoptosis was completely prevented by the addition of guanosine at time points up to 12 hours, after which caspase 3 activity increased and apoptosis was not reversible. MPA treatment caused marked down-regulation of the MAP kinase kinase/extracellular regulatory kinase (MEK/Erk) pathway at 3 hours while simultaneously increasing the phosphorylation of c-Jun kinase. In addition, MPA strongly down-regulated the mammalian target of rapamcyin (mTOR) pathway, as indicated by the decreased phosphorylation of p70 S6 kinase and of 4EBP1. Inhibition of either the mitogen-activated protein kinase (MAPK) or the mTOR pathway alone by standard pharmacologic inhibitors did not induce apoptosis in IL-3-dependent cells, whereas inhibition of both pathways simulated the effects of MPA treatment. These results indicate that IMPDH inhibitors may be effective in modulating signal transduction pathways in hematopoietic cells, suggesting their usefulness in chemotherapeutic regimens for hematologic malignancies.
Computer network architectures and operating experience of data networks at ICCC'78: promise and practice

Abstract A review is given of the sessions of the International Computer Communications Conference '78 which were devoted to Computer Network Architectures and to Operating Experience of Data Networks. The basic concepts of some major architectures as devised by some of the leading computer manufacturers in Japan and the United States are compared. Under Operating Experience of Data Networks the key observations and conclusions from 8 papers dealing with multiple-user data networks are reviewed. Included are circuit-switched, packet-switched and message-switched types. The applications range from university services to international banking and general purpose data communication. Experiences with software development, service availability, installation and fault correction aids, and usage are reviewed.
Angular anisotropy of surface multiple scattering: analysis of carbon contamination on an Ir{110} surface

Abstract Multiple scattering (MS) effects resulting from the successive collisions of 4 keV Ar + with iridium and carbon atoms were investigated on a carbon contaminated Ir{110} surface. The experimental measurements were made at different crystallographic directions. The results show that (i) detection of MS provides an extremely sensitive method for monitoring the surface contamination and (ii) the MS intensity exhibits strong anisotropies as a function of incident angle (α), azimuthal angle (δ), and scattering angle (Θ). Combined with Monte Carlo computer simulations, the MS angular anisotropies allow an identification of the scattering and recoiling processes and provide unique structural information regarding the location of the carbon impurities on the surface. The experimental results and simulations are consistent with carbon impurity sites located inside the 〈110〉 troughs and above the surface. The carbon coverage is estimated to be ∼ 0.5 ML.
Intact implicit memory in patients with frontal lobe lesions.

Patients with frontal lobe lesions and control subjects were administered tests of word-stem completion priming. In this implicit memory test, subjects are first presented words (e.g. MOTEL, PARADE) in an incidental learning paradigm. Following word presentation, subjects are shown word stems (e.g. MOT, PAR) and asked to produce the first word that comes to mind. Patients with frontal lobe lesions exhibited normal levels of word-stem completion. These findings indicate that implicit memory can operate normally despite damage to the prefrontal cortex. The present results substantiate previous neuropsychological and positron emission tomography findings which indicate that word priming depends critically on posterior cortical areas.
Correlation and Redefinition of the Goodsprings Dolomite, Southern Nevada and Eastern California

The Goodsprings Dolomite is confined to an area of approximately 8,200 sq km in southern Nevada and eastern California. Owing to its general lack of fossils and monotonous lithology, previous workers have mapped the Goodsprings as Cambrian-Devonian undifferentiated. The purpose of the present study was to subdivide the Goodsprings Dolomite into regionally mappable units and to correlate these units with laterally equivalent, presently recognized, miogeosynclinal formations to the north and west. Results suggest: (1) the Goodsprings contains many well-defined, regionally mappable units; (2) approximately the lower one-half of the formation is lithologically equivalent to the Middle to Upper Cambrian Bonanza King Formation; (3) much of the remaining Goodsprings is lithologically and faunally equivalent to the Upper Cambrian Nopah Formation; (4) in the northeastern part of the outcrop area, strata lithologically equivalent to the Lower Ordovician Pogonip Group (undifferentiated) were found; (5) the uppermost 200 m of Goodsprings is lithologically variable and equivalent in age to the Upper Ordovician Ely Springs Dolomite; however, owing to a lack of lithologic equivalency with the Ely Springs, a new formational name, the “Mountain Springs Formation,” is proposed for these strata; (6) two post–Late Cambrian—pre-Middle Devonian disconformities are indicated, which cause the progressive “pinching-out” of the Pogonip Group and Mountain Springs Formation in a southeasterly direction. On the basis of these findings, the formational rank of the Goodsprings Dolomite should be dropped.
Screening lambdagt recombinant clones by hybridization to single plaques in situ

A rapid, direct method for screening single plaques of Agt recombinant phage is described. The method allows at least 10(6) clones to be screened per day and simplifies physical containment of recombinants.
Introduction to Grade Retention Among Struggling Readers

The passage of the No Child Left Behind Act of 2001 has placed a renewed emphasis on ensuring that every student learns to read. Nevertheless, many students continue to struggle with reading. If no...
Two blossoming proofs of the Lane-Riesenfeld algorithm

The standard proof of the Lane-Riesenfeld algorithm for inserting knots into uniform B-spline curves is based on the continuous convolution formula for the uniform B-spline basis functions. Here we provide two new, elementary, blossoming proofs of the Lane-Riesenfeld algorithm for uniform B-spline curves of arbitrary degree.
Motor vehicle crash fatalities: The effects of race and marital status

Abstract This study compared victims of motor vehicle fatalities to deaths due to natural causes. It was hypothesized that the race and marital status of victims would have significant effects on the likelihood of death from motor vehicle accidents. In particular, African Americans were expected to have fatalities significantly higher than those of whites. Cross-sectional data on a universe of all deaths occurring in the United States of men and women aged 15 and above from the 1992 Mortality Detail File were analyzed to examine the association between black race and marital status, and automobile fatalities. Statistical adjustments were made for possible confounders, such as age, normal occupation of victims, nativity status, region of the country of the accident, day of the week, and month. Multivariate logistic regression models were fitted to the data. Compared to whites, African Americans were significantly less likely (OR = 0.732, CI = 0.693 − 0.772) to die from motor vehicle crashes relative to other causes of death. Native Americans were more likely (OR = 2.326, CI = 1.947 − 2.779) than whites to die of accidents, and Asians were significantly more likely than whites to become victims of fatal crashes (OR = 1.654, CI = 1.438 − 1.902). As for marital status, compared to married individuals, divorced persons were significantly more likely to die of automobile accidents (OR = 1.205, CI = 1.147 − 1.267). Widowed and single individuals were less likely to die of motor vehicle accidents (OR = 0.819, CI = 0.781 − 0.860; OR = 0.654, CI = 0.618 − 0.692) than married individuals. Divorced individuals had elevated risks of motor vehicle accidents, a finding that is consistent with those examining mortality from other external causes (e.g. suicide and homicide). It was suggested that divorce may be a potentially stressful life event that might leave some individuals temporarily incapacitated to operate automobiles safely. Race was expected to influence accidents due to the role of social disadvantage. However, only Native Americans, Hispanics, and Asians had fatality risks above those of whites. Blacks were significantly less likely to become victims of fatal crashes. Hence, social disadvantage is not enough to explain racial differences in accident victimization in the United States. Potential confounders, such as alcohol impairment, seat belt use, age of automobiles, operator behavior, and road conditions may offer alternative explanations.
What Can Semiconductor Fabs Do for the Green Earth

This PDF file contains the editorial “What Can Semiconductor Fabs Do for the Green Earth?” for JM3 Vol. 7 Issue 02
The ligand-selectivity of cloned human and rat opiate mu receptors studied with [125I]IOXY-AGO

Abstract The recent molecular cloning of μ, δ and κ opiate receptors (1–5) has created new opportunities for the study of opiate receptors. The recent cloning of the human μ receptor (6) has shown that there is a high homology between the predicted human and rat μ receptor sequences, but also some differences in sequence. We therefore sought significant changes in the ligand-selectivity profile of these two receptors expressed in the COS and CHO cell lines under identical assay conditions. We used the novel agonist ligand [ 125 I]IOXY-AGO (6β-[ 125 Iodo]-3,14-dihydroxy-17-methyl-4,5α-epoxymorphinan) since its high specific activity (2200 Ci/mmol) and high affinity for μ opioid receptors generated a high signal-to-noise ratio with use of relatively few expressing cells. (7). The results indicate substantial similarities in ligand-selectivity profile of the human and rat μ receptors, but also modest differences.
Identification of isomeric amides of itaconic acid by proton magnetic resonance spectroscopy

Two half amides of itaconic acid, (1) and (2), have been synthesized and identified by proton magnetic resonance spectroscopy as a preliminary to an interpretation of the mechanism of action of succinate thiokinase on guanosine triphosphate substrates.
Tremor-tide correlations and near-lithostatic pore pressure on the deep San Andreas fault.

Amanda Thomas and colleagues identify a correlation between non-volcanic tremor activity near Parkfield, California, and extremely small, tidally induced shear stress parallel to the San Andreas fault. Non-volcanic tremor is a weak seismic signal observed periodically on some major faults. Thomas et al. suggest that the Parkfield tremors may represent shear failure on a critically stressed fault in the presence of near-lithostatic pore pressure. Similarities with tremor in subduction-zone environments, such as Cascadia and Japan, indicate that these findings may also be relevant to other tectonic settings. Non-volcanic tremor was discovered nearly a decade ago; however, a thorough explanation of the geologic process responsible for tremor generation has yet to be determined. A robust correlation is now identified between extremely small, tidally induced shear stress parallel to the San Andreas fault and non-volcanic tremor activity near Parkfield, California. Such tremor may represent shear failure on a critically stressed fault in the presence of near-lithostatic pore pressure. Since its initial discovery nearly a decade ago1, non-volcanic tremor has provided information about a region of the Earth that was previously thought incapable of generating seismic radiation. A thorough explanation of the geologic process responsible for tremor generation has, however, yet to be determined. Owing to their location at the plate interface, temporal correlation with geodetically measured slow-slip events and dominant shear wave energy, tremor observations in southwest Japan have been interpreted as a superposition of many low-frequency earthquakes that represent slip on a fault surface2,3. Fluids may also be fundamental to the failure process in subduction zone environments, as teleseismic and tidal modulation of tremor in Cascadia and Japan and high Poisson ratios in both source regions are indicative of pressurized pore fluids3,4,5,6,7. Here we identify a robust correlation between extremely small, tidally induced shear stress parallel to the San Andreas fault and non-volcanic tremor activity near Parkfield, California. We suggest that this tremor represents shear failure on a critically stressed fault in the presence of near-lithostatic pore pressure. There are a number of similarities between tremor in subduction zone environments, such as Cascadia and Japan, and tremor on the deep San Andreas transform3,4,5,6,7,8,9,10,11,12, suggesting that the results presented here may also be applicable in other tectonic settings.
Carbon and oxygen diffusion in calcite: Effects of Mn content and PH2O

The diffusion rates of carbon and oxygen in two calcite crystals of different Mn contents have been studied between 500° and 800° C in a CO2-H2O atmosphere (PCO2=1−5 bars, PH2O=0.02−24 bars) labeled with 13C and 18O. Isotope concentration gradients within annealed specimens were measured using a secondary ion microprobe by depth profiling parallel and perpendicular to the c axis. Despite the anisotropic structure of calcite, the diffusion of carbon and oxygen are both very nearly isotropic. Least-squares fitting of the carbon data to an Arrhenius relation gives an activation energy of 87±2 kcal/mole, with D0 terms dependent only slightly upon direction: $$D_{\text{0}} {\text{(}}\parallel c{\text{) = }}\left( {9\frac{{ + 12}}{{ - 5}}} \right){\text{x10}}^{\text{2}} cm^2 /s$$ (1) , $$D_{\text{0}} {\text{(}} \bot c{\text{) = }}\left( {5\frac{{ + 6}}{{ - 3}}} \right){\text{x10}}^{\text{2}} cm^2 /s$$ (2) . These results are in close agreement with previous determinations. Results for oxygen diffusion, however, give D values much larger than those previously reported for dry conditions; at 650° to 800° C the D values are two orders of magnitude larger. The diffusion of oxygen, unlike carbon, is strongly dependent on water pressure, as well as Mn content, and does not fit an Arrhenius relation over the entire temperature range. On the basis of these observations and considerations of the defect chemistry of calcite, it is proposed that carbon migrates as a Frenkel pair. The diffusion of oxygen, however, appears to be more complicated and may depend upon several simultaneous mechanisms.
The Regularity of Sustained Firing Reveals Two Populations of Slowly Adapting Touch Receptors in Mouse Hairy Skin

Touch is initiated by diverse somatosensory afferents that innervate the skin. The ability to manipulate and classify receptor subtypes is prerequisite for elucidating sensory mechanisms. Merkel ce...
Perchlorate exposure in pregnancy and cognitive outcomes in children: it's not your mother's thyroid.

Perchlorate (ClO−4) is utilized in manufacturing rocket fuel, fireworks, and airbag inflation systems as well as being formed naturally in the atmosphere (1). It is stable and soluble in water and has been detected in drinking water, vegetables, and even breast milk. Perchlorate is a direct inhibitor of iodine transport and is the best characterized toxicant with respect to mechanism of action, although a range of environmental toxicants have been identified that disrupt thyroid hormone synthesis, metabolism, and action (2). At a sufficient dose and duration of exposure, perchlorate can reduce thyroid hormone production by reducing iodine uptake into the thyroid. Iodine is essential for thyroid hormone production and must be derived from dietary sources (3). Perchlorate antagonism of iodine transport is additive with other inhibitors, such as thiocyanate, found in cigarette smoke. The impact of perchlorate on thyroid function, especially in pregnancy, has led to intense focus on determining acceptable levels of perchlorate and other iodine inhibitors in the water supply (4, 5).
Survey course in organizational communication consulting: A processual model

This description of a graduate course in communication consulting has two purposes. First, the course is offered as a possible method for improving the professionalism of graduates of communication programs who wish to consult with organizations on communication change. Second, the manuscript emphasizes the importance of a processual model for use in designing and teaching courses in communication consulting. Issues discussed, readings selected, and assignments given for the three phases of the class structure are explicated.
Processes affecting geochemistry and contaminant movement in the middle Claiborne aquifer of the Mississippi embayment aquifer system

Groundwater chemistry and tracer-based age data were used to assess contaminant movement and geochemical processes in the middle Claiborne aquifer (MCA) of the Mississippi embayment aquifer system. Water samples were collected from 30 drinking-water wells (mostly domestic and public supply) and analyzed for nutrients, major ions, pesticides, volatile organic compounds (VOCs), and transient age tracers (chlorofluorocarbons, tritium and helium-3, and sulfur hexafluoride). Redox conditions are highly variable throughout the MCA. However, mostly oxic groundwater with low dissolved solids is more vulnerable to nitrate contamination in the outcrop areas east of the Mississippi River in Mississippi and west Tennessee than in mostly anoxic groundwater in downgradient areas in western parts of the study area. Groundwater in the outcrop area was relatively young (apparent age of less than 40 years) with significantly (p 50 m depth) indicated contaminant movement from shallow parts of the aquifer into deeper oxic zones. Given the persistence of nitrate in young oxic groundwater that was recharged several decades ago, and the lack of a confining unit, the downward movement of young contaminated water may result in higher nitrate concentrations over time in deeper parts of the aquifer containing older oxic water.
Mechanisms in cyclophosphamide induction of cytogenetic damage in human lymphocyte cultures

Abstract Low-dose cyclophosphamide treatment of human lymphocyte cultures in concentrations ranging from 0.001 to 0.00001 μg/ml produced a statistically significant dose response in chromosome breakage and cell death. However, a dose as high as 0.2 μg/ml did not produce significant damage in comparably treated whole blood cultures. These results suggest that lymphocytes in culture have the ability to metabolize the nonmutagenic cyclophosphamide parent compound to its more mutagenic metabolite, but that such conversion may be prevented by binding of cyclophosphamide to red blood cells.
Terrain Reconstruction of Glacial Surfaces : Robotic Surveying Techniques

The capability to monitor natural phenomena using mobile sensing is a benefit to the Earth science community, given the potentially large impact that humans have on naturally occurring processes. Such phenomena can be readily monitored using networks of mobile sensor nodes that are tasked to regions of interest by scientists. In our article, we hone in on a very specific domain, elevation changes in glacial surfaces, to demonstrate a concept applicable to any spatially distributed phenomena (e.g., temperature or humidity). Our article leverages the sensing of a vision-based odometry system and the design of robotic surveying navigation rules to reconstruct scientific areas of interest, with the goal of monitoring elevation changes in glacial regions. The reconstruction methodology presented makes use of Gaussian process (GP) regression to combine sparse visual landmarks extracted from the glacial scenery into a dense topographic map. Further, this method allows for the natural inclusion of a priori terrain knowledge, such as existing digital elevation models. Results from this system are presented from a three-dimensional (3-D) glacial simulation modeled after actual field trials on Alaskan glaciers. Additionally, we introduce a theory behind spatial coverage, in the context of sampling, as achieved by an intelligently navigating agent. Finally, we validate the output from our methodology and provide results and show that the reconstructed terrain error complies with acceptable mapping standards found in the scientific community.
The potency and Group I antigen content of six commercially prepared grass pollen extracts

Abstract Commercially prepared extracts of 6 different grass pollens, rye, fescue, sweet vernal, june, velvet, and redtop were compared for their skin reactivity, rye Group I allergen content, and protein nitrogen units (PNU) content claimed by the manufacturer and redetermined at the time the extracts were used. There was a high correlation between skin reactivity and Group I allergen content. There was no correlation between the PNU claimed and either skin reactivity or Group I allergen content. The PNU determined at the time the extracts were used showed an improved correlation with biologic activity.
Automatic inspection planning within a feature-based CAD system

Abstract This paper describe a CIM system which incorporates automatic generation of inspection on plans for coordinate measuring machines (CMMs). Design is done in terms of form features. Associated with each feature are inspection plan fragments (IPFs) which are instances of inspection procedures. There are three basic types of plan fragments for CMMs: (1) fragments for checking the internal dimensions of a feature, (2) fragments for checking the relationships between features, and (3) modified fragments for use when the feature to be inspected intersects another feature. Using this approach, a list of suitable inspection points and approach vectors is generated. A path planner then combines the elements of the list to produce a valid inspection path for the CMM. The system is consistent with the accepted ANSI Y14.5M standard for dimensioning and tolerancing as well as with observed industrial practice.
Trapnell versus the lexical factor: More ado about nothing?

Although Trapnell (1994) provides an interesting demonstration of the orthogonal relations between intuitively constructed English‐language adjective scales for competence and liberalism, the criti...
Evaluating natural language systems: a sourcebook approach

This paper reports progress in development of evaluation methodologies for natural language systems. Without a common classification of the problems in natural language understanding authors have no way to specify clearly what their systems do, potential users have no way to compare different systems and researchers have no way to judge the advantages or disadvantages of different approaches to developing systems.
The Ecological and Population Validity of Reading Interventions for Adolescents: Can Effectiveness Be Generalized?.

This article examined the ecological and population validity of research on reading interventions for adolescents in Grades 6 through 12. The 26 studies meeting selection criteria were analyzed to ...
2-acetylaminofluorene-induced unscheduled DNA synthesis in hepatocytes isolated from 3-methylcholanthrene treated rats.

Summary The dose-dependent induction of unscheduled DNA synthesis (UDS) by 2-acetylaminofluorene (AAF) and N -OH-2-acetylaminoflucrene (N-OH AAF) in primary rat hepatocytes isolated from untreated and 3-methylcholanthrene (3-MC) treated rats was investigated. 3-MC treatment was not necessary for the dose-dependent induction of UDS induced by N-OH AAF, suggesting the presence of enzyme levels adequate for its esterification to an active form in isolated primary hepatocytes. Although all doses of AAF increased the level of [ 3 H] thymidine incorporation above that of the control, a dose-dependent response could not be demonstrated, suggesting inadequate constitutive levels of N-hydroxylating enzymes. Treatment of rats with 3-MC 24 h prior to hepatocyte isolation resulted in a dose-dependent induction of UDS by AAF. 3-MC treatment increased the amount of UDS per cell, as well as the percentage of cells induced to repair their DNA.
H-index, mentoring-index, highly-cited and highly-accessed: How to evaluate scientists?

How best to evaluate scientists within a peer group is a difficult task. This editorial discusses the use of the H-index and total citations. It also raises the consideration of a mentoring-index and the value of understanding the frequency that a published paper is accessed by readers.
EVALUATING A COMMUNITY COLLEGE HONORS PROGRAM: PERCEPTIONS OF EFFECTIVENESS AND VALUE

In this study, we evaluated the effectiveness and value of the Maricopa Community College District Honors Program. The results of a faculty questionnaire revealed favorable attitudes toward the program, with more than 90% of respondents indicating that they enjoy teaching honors courses. Telephone interviews with faculty revealed that they especially enjoy working with honors students because they are motivated and willing to learn. Alumni questionnaire respondents were also generally positive about the program and felt that they are currently applying the knowledge and skills they acquired as honors students. Current student responses were also favorable toward the honors program, agreeing in most cases with alumni responses. A primary finding of this evaluation was that all of the evaluation participants considered increasing on‐campus recruitment and retention efforts as a means of improving the honors program. Eliminating concurrent classes and making more honors courses available to students were als...
Hepatocyte Growth Factor Suppresses Renal Interstitial Myofibroblast Activation and Intercepts Smad Signal Transduction

Interstitial myofibroblasts are α-smooth muscle actin-positive cells that play a crucial role in the accumulation of excess extracellular matrix during renal interstitial fibrogenesis. Despite their importance in the pathogenesis of renal fibrosis, relatively little is known about the regulators and the mechanism controlling the activation of renal interstitial myofibroblasts in disease conditions. Here, we show that hepatocyte growth factor (HGF) acts as a potent inhibitor of the transforming growth factor (TGF)-β1-mediated myofibroblastic activation from normal rat renal interstitial fibroblasts (NRK-49F). Simultaneous incubation of HGF abolished TGF-β1-induced de novo α-smooth muscle actin expression, F-actin reorganization, and interstitial collagen I overproduction in a dose-dependent manner. To decipher the mechanism underlying HGF antagonizing TGF-β1’s action, we examined the effects of HGF on TGF-β1-mediated Smad signaling. HGF neither inhibited Smad-2/3 phosphorylation and their association with Smad-4 induced by TGF-β1, nor significantly affected inhibitory Smad-6 and -7 expression and cellular abundance of Smad transcriptional co-repressors in NRK-49F cells. However, pretreatment with HGF markedly attenuated activated Smad-2/3 nuclear translocation and accumulation. This action of HGF was apparently dependent on HGF-mediated extracellular signal-regulated kinase-1 and -2 (Erk-1/2) phosphorylation and activation. Inhibition of Erk-1/2 activation by Mek kinase inhibitor PD98059 restored TGF-β1-mediated Smad-2/3 nuclear accumulation and myofibroblast activation. In vivo, HGF selectively blocked Smad-2/3 nuclear accumulation in renal interstitial cells in the fibrotic kidneys induced by unilateral ureteral obstruction. Therefore, HGF suppresses TGF-β1-mediated renal interstitial myofibroblastic activation; and this action of HGF is likely related to a mitogen-activated protein kinase-dependent blockade of Smad nuclear translocation.