cssi/SciSciGPT-SciSciNet huggingface dataset:
Relationship between adduct formation, rates of excision repair and the cytotoxic and mutagenic effects of structurally-related polycyclic aromatic carcinogens.

Abstract The cytotoxic and mutagenic effect of 1-nitrosopyrene (1-NOP) and N -acetoxy-2-acetylaminofluorene (N-AcO-AAF) were compared with that of (±)-7β,8α-dihydroxy-9α,10-epoxy-7,8,9,10-tetrahydrobenzo[ a ]pyrene (BPDE) as a function of the initial frequency of adducts formed in the DNA of repair-proficient diploid human fibroblasts and the fraction remaining at the time the cells replicate their DNA. The principal adducts of all three agents involve guanine. The initial level of BPDE-, 1-NOP-, or N-AcO-AAF-induced adducts per 10 6 nucleotides required to lower the survival of these cells to 37% of the control was 8, 25, and 50, respectively. The frequency of mutants per 10 6 clonable cells induced at those levels of initial adduct formation was 160, 80, and 40, respectively. We determined the rate of excision repair of these adducts from the overall genome, from the individual strands of the hypoxanthine phosphoribosyltransferase ( HPRT ) gene, and in the case of 1-NOP and BPDE, at the level of individual nucleotides in the nontranscribed strand of exon 3 of that gene, a region where mutations induced by those agents are particularly frequent. 1-NOP-induced adducts were excised from the overall genome and from the individual strands of HPRT at a rate 2–3 times faster than BPDE-induced adducts. The average rate of repair of 1-NOP-induced adducts in exon 3 was also 2–3 times faster than the average rate of repair of BPDE-induced adducts. However, at particular nucleotides 1-NOP-induced adducts were repaired much faster, or slower, or in some cases at a rate equal to that of BPDE-induced adducts. Excision repair of N-AcO-AAF-induced adducts (i.e., deacetylated aminofluorene residues) was significantly slower than that of BPDE- or 1-NOP-induced adducts, and was not strand-specific. In an in vitro assay, BPDE adducts were four times more effective in blocking transcription than were 1-NOP or N-AcO-AAF-induced adducts. We conclude that the cytotoxic and mutagenic effect of these carcinogens reflect a complex interplay of adduct conformation, ability of adducts to block replication and transcription, and variation in the rate of excision repair, even at the nucleotide level.
Mass quantization of the Schwarzschild black hole

We examine the Wheeler-DeWitt equation for a static, eternal Schwarzschild black hole in Kucha\ifmmode \check{r}\else \v{r}\fi{}-Brown variables and obtain its energy eigenstates. Consistent solutions vanish in the exterior of the Kruskal manifold and are nonvanishing only in the interior. The system is reminiscent of a particle in a box. States of definite parity avoid the singular geometry by vanishing at the origin. These definite parity states admit a discrete energy spectrum, depending on one quantum number which determines the Arnowitt-Deser-Misner mass of the black hole according to a relation conjectured long ago by Bekenstein $M\ensuremath{\sim}\sqrt{n}{M}_{p}.$ If attention is restricted only to these quantized energy states, a black hole is described not only by its mass but also by its parity. States of indefinite parity do not admit a quantized mass spectrum.
Recipe for High-Tc Transition-Metal Chalcogenide Superconductors

The conditions for the occurrence of superconductivity in cuprates are enumerated. There is a minimum of seven, which I will discuss in some detail. They may be taken as a recipe in the search for superconductors at elevated temperatures with other transition-metal chalcogenide compounds. Furthermore, it is apparent that in any theory one is involved in minimizing the many-body energy in a multiparameter space outlined by the conditions enumerated in this paper.
Multiple sites of crossing over within the Eb recombinational hotspot in the mouse.

The Eb gene of the mouse major histocompatibility complex (MHC) contains a well-documented hotspot of recombination. Twelve cases of intra-Eb recombination derived from the b, d, k and s alleles of the Eb gene were sequenced to more precisely position the sites of meiotic recombination. This analysis was based on positioning recombination breakpoints between nucleotide polymorphisms found in the sequences of parental haplotypes. All twelve cases of recombination mapped within the second intron of the Eb gene. Six of these recombinants, involving the k and s haplotypes, mapped to two adjoining DNA segments of 394 and 955 base pairs (bp) in the 3′ half of the intron. In an additional two cases derived by crossing over between the d and s alleles, breakpoints were positioned to adjoining segments of 28 and 433 bp, also in the 3′ half of the intron. Finally, four b versus k recombinants were mapped to non-contiguous segments of DNA covering 2.9 kb and 1005 bp of the intron. An analysis of the map positions of crossover breakpoints defined in this study suggests that the second intron of the Eb gene contains a recombinational hotspot of approximately 800–1000 bp which contains at least two closely linked recombinationally active sites or segments. Further examination of the sequence data also suggests that the postulated location for the recombinational hotspot corresponds almost precisely to an 812 bp sequence that shows nucleotide sequence similarity to the MT family of middle repetitive DNA.
Ionization Kinetics of the Carbon Acid Phenindione

Abstract The ionization kinetics of carbon acids are slow relative to those of classical acids and bases. Phenindione (2‐phenyl‐1,3‐indandione) is a 1,3‐diketone carbon acid of macroscopic experimental pKa 4.09 at 25° and ionic strength 0.1. The ionization kinetics of phenindione were determined at an ionic strength of 0.1 and 25° using stopped‐flow spectrophotometry and a pH jump technique. A log k obs ‐pH profile for the approach to the ionization equilibrium was determined, and a mechanism consistent with the profile was postulated. The percent enol versus diketo form of phenindione and the pKa enol and pKa diketo were calculated from the kinetic data. Phenindione acid deprotonation kinetics by various oxygen and nitrogen bases suggested that, with bases of pKa 4.7‐8.5 and in the pH 5‐8.5 range, the acidic phenindione proton was ∼ 45% transferred in the rate‐determining transition state.
Synthesis of 14-[2H]arteether, an experimental antmalarial drug

A reaction sequence employing a fungus mediated oxidation of arteether, an experimental antimalarial drug, was used to introduce a hydroxyl group on C-14. The hydroxyl group was replaced by a deuterium by preparing the tosylate and reductively cleaving it with sodium borodeuteride in DMSO. A reaction sequence to introduce a second label was also demonstrated it involved oxidation of the alcohol, with catalytic quantities of tetra-n-propylammonium perruthenate, followed by reduction with sodium borodeuteride to regenerate the alcohol. Use of both reactions sequences yield arteether containing two deuterium.
On deficits and unemployment

Entre 2007 et 2011 le chomage s’est accru notablement dans la plupart des pays europeens. Durant la meme periode, les deficits exterieurs de nombreux pays europeens se sont fortement reduits. Nous utilisons un modele d’equilibre general, de type ricardien et reposant sur des rigidites salariales, couvrant trente-quatre pays, pour analyser la relation entre les ajustements exterieurs, les pnb relatifs et le chomage durant cette periode. Notre analyse permet de decomposer les mecanismes d’ajustement par le biais du chomage et de la baisse des salaires. Le chomage a joue le role le plus important, mais les baisses du pnb nominal se sont mieux refletees dans le pnb reel.JEL Code: F16, F32
Electromigration Damage in Al-Cu Thin Films

Al-3% Cu stripes are powered in situ in the transmission electron microscope in order to study the effect of copper on the mechanisms of failure due to electro-migration. Consideration is given to the effects of various heat treatments and the depletion of Cu in the damage zone.
Noise and signal properties in PSF-based fully 3D PET image reconstruction: an experimental evaluation

The addition of accurate system modeling in PET image reconstruction results in images with distinct noise texture and characteristics. In particular, the incorporation of point spread functions (PSF) into the system model has been shown to visually reduce image noise, but the noise properties have not been thoroughly studied. This work offers a systematic evaluation of noise and signal properties in different combinations of reconstruction methods and parameters. We evaluate two fully 3D PET reconstruction algorithms: (1) OSEM with exact scanner line of response modeled (OSEM+LOR), (2) OSEM with line of response and a measured point spread function incorporated (OSEM+LOR+PSF), in combination with the effects of four post-reconstruction filtering parameters and 1-10 iterations, representing a range of clinically acceptable settings. We used a modified NEMA image quality (IQ) phantom, which was filled with 68Ge and consisted of six hot spheres of different sizes with a target/background ratio of 4:1. The phantom was scanned 50 times in 3D mode on a clinical system to provide independent noise realizations. Data were reconstructed with OSEM+LOR and OSEM+LOR+PSF using different reconstruction parameters, and our implementations of the algorithms match the vendor's product algorithms. With access to multiple realizations, background noise characteristics were quantified with four metrics. Image roughness and the standard deviation image measured the pixel-to-pixel variation; background variability and ensemble noise quantified the region-to-region variation. Image roughness is the image noise perceived when viewing an individual image. At matched iterations, the addition of PSF leads to images with less noise defined as image roughness (reduced by 35% for unfiltered data) and as the standard deviation image, while it has no effect on background variability or ensemble noise. In terms of signal to noise performance, PSF-based reconstruction has a 7% improvement in contrast recovery at matched ensemble noise levels and 20% improvement of quantitation SNR in unfiltered data. In addition, the relations between different metrics are studied. A linear correlation is observed between background variability and ensemble noise for all different combinations of reconstruction methods and parameters, suggesting that background variability is a reasonable surrogate for ensemble noise when multiple realizations of scans are not available.
An agreement centric access control mechanism for business to business e-commerce

We argue that matrix-based models are inadequate for regulating business to business (or B2B, for short) e-commerce due to the diversity, complexity and potential large number of commercial agreements that have to be supported. To deal with these issues, we propose in this paper an agreement-centric access control model. The paper introduces the concept of communication agreement (CAR) as a means for specifying contractual terms, and presents the CAR enforcement mechanism. We explore the expressive power of the model and show that it can implement regulations which cannot expressed using conventional mechanisms alone. The paper also describes a prototype implementation; the preliminary performance results indicate that the enforcement mechanism is quite affordable, even in its present, experimental stage.
PedGenie: meta genetic association testing in mixed family and case-control designs

PedGenie software, introduced in 2006, includes genetic association testing of cases and controls that may be independent or related (nuclear families or extended pedigrees) or mixtures thereof using Monte Carlo significance testing. Our aim is to demonstrate that PedGenie, a unique and flexible analysis tool freely available in Genie 2.4 software, is significantly enhanced by incorporating meta statistics for detecting genetic association with disease using data across multiple study groups. Meta statistics (chi-squared tests, odds ratios, and confidence intervals) were calculated using formal Cochran-Mantel-Haenszel techniques. Simulated data from unrelated individuals and individuals in families were used to illustrate meta tests and their empirically-derived p-values and confidence intervals are accurate, precise, and for independent designs match those provided by standard statistical software. PedGenie yields accurate Monte Carlo p-values for meta analysis of data across multiple studies, based on validation testing using pedigree, nuclear family, and case-control data simulated under both the null and alternative hypotheses of a genotype-phenotype association. PedGenie allows valid combined analysis of data from mixtures of pedigree-based and case-control resources. Added meta capabilities provide new avenues for association analysis, including pedigree resources from large consortia and multi-center studies.
Structure of calmodulin refined at 2.2 A resolution.

Abstract The crystal structure of mammalian calmodulin has been refined at 2.2 A (1 A = 0.1 nm) resolution using a restrained least-squares method. The final crystallographic R-factor, based on 6685 reflections in the range 2.2 A ≤ d ≤ 5.0 A with intensities exceeding 2.5 σ, is 0.175. Bond lengths and bond angles in the molecule have root-mean-square deviations from ideal values of 0.016 A and 1.7 °, respectively. The refined model includes residues 5 to 147, four Ca2+ and 69 water molecules per molecule of calmodulin. The electron density for residues 1 to 4 and 148 is poorly defined, and they are not included in the model. The molecule is shaped somewhat like a dumbbell, with an overall length of 65 A; the two lobes are connected by a seven-turn α-helix. Prominent secondary structural features include seven α-helices, four Ca2+-binding loops, and two short, double-stranded antiparallel beta-sheets between pairs of adjacent Ca2+-binding loops. The four Ca2+-binding domains in calmodulin have a typical EF hand conformation (helix-loop-helix) and are similar to those described in other Ca2+-binding proteins. The X-ray structure determination of calmodulin shows a large hydrophobic cleft in each half of the molecule. These hydrophobic regions probably represent the sites of interaction with many of the pharmacological agents known to bind to calmodulin.
Relation of Sexual Behaviors, Values, and Conflicts to Avowed Happiness

A questionnaire study of 101 college students related attitudes toward sexual intimacy to adjustment, measured by avowed happiness, and to religiosity. Religiosity correlated negatively with liberality and positively with happiness (r = .33, p < .001). Other trends suggested a relation between unhappiness and several measures of liberality and conflict. The results support other studies in showing a small relationship between adjustment and adherence to traditional, conservative values. Data are discussed in terms of different theories of the role of value conflicts in the etiology of neurosis. Other findings show that in Hawaii Caucasians are more liberal than Orientals, males are more liberal than females, estimates of parental outlook are less liberal than S‘s ideal behavior, and S‘s own behavior is more liberal than his ideal (in boys only) and more conservative than what his peers are believed to accept (in girls only).
Sexual Initiation, Parent Practices, and Acculturation in Hispanic Seventh Graders

BACKGROUND: Hispanic youths have high rates of sexually transmitted infections and pregnancies, yet little research has targeted multiple protective/risk factors for early sexual initiation in this group. This study examined two main factors—parenting practices and acculturation—on early sexual initiation among Hispanic middle school students in Texas. METHODS: Using data from Hispanic seventh graders (N = 655) in 15 urban middle schools in southeast Texas, we examined the association between parental monitoring/parent-child communication about sexual health and sexual initiation. RESULTS: After controlling for age, gender, parent/guardian education, family structure, acculturation level, and intervention status, the likelihood of ever having sex decreased 50% for every 1-point increase in the parental monitoring score (AOR = 0.50;95%CI = 0.34,0.75). No association was found between ever having sex and parent-child communication scores (AOR = 1.29;95%CI = 0.76,2.18). Furthermore, parental monitoring differed significantly between acculturation levels, 1-way analysis of variance F(2,652) = 5.07, p < 0.007. This finding was unrelated to the parental monitoring-initiation association in the multivariable model. CONCLUSION: Parental monitoring may delay sexual initiation among Hispanic middle school students. Parental monitoring differs by acculturation levels, warranting further investigation. These findings can inform school-based, parent-involved interventions designed to delay sexual initiation among Hispanic youth.
Comments on the approximate solution of the diffusion equation: I

On the basis of a previous general formulation (Bull. Math. Biophysics,15, 21–29, 1953a) a discussion is given of the error in the approximation method of N. Rashevsky. This error, inherent in the method when the metabolic rate is different at each point in the cell, is discussed in detail and numerical values are presented for two particular cases: the rate proportional to the concentration and the rate a prescribed function of the spatial coordinates. It is shown that the formulation for the first case also applies to several other cases, that the error is negligible provided the rate is sufficiently small, and that the error is fairly sensitive to the cell size. If the rate depends upon the coordinatesalone a small rate is not sufficient to insure a negligible error. The relations between the exact method, the standard approximate method, an earlier approximate method (Physics,7 260, 1936), and a more recent refinement (Bull. Math. Biophysics,10, 201, 1948) of the standard method are discussed.
Synthesis and coordination chemistry of macrocyclic phosphine ligands

Abstract Macrocyclic phosphine compounds are sought after as ligands for transition metal complexes because of their strong binding properties. As such, these ligands are particularly useful in applications where robust transition metal–phosphine complexes are employed, as in homogeneous catalysis or in radiopharmaceuticals. This review summarizes the development of macrocyclic phosphine ligands, including their preparation and coordination to transition metals. Synthetic methods for the preparation of phosphine macrocycles are discussed, including methods for controlling ring size and stereochemistry. The coordination chemistry of macrocyclic phosphines is also reviewed. Many phosphine macrocycles are synthesized by template methods, and methods for removing the templating metal from the macrocyclic ligand are reviewed.
A new software correction approach to volume averaging artifacts in CT.

Abstract The nature of artifacts in computed tomography, due to nonlinear partial volume effects, is briefly reviewed. A methodology for correction of these artifacts is proposed. This methodology utilizes a correction algorithm for post-processing the original reconstructed CT image. The algorithm utilizes local CT values to predict the probability of volume averaging of bone, air and tissue, and incorporates information from the original image on the spatial extent of the averaging, to correct the nonlinear effects. The algorithm is successfully demonstrated on mathematical phantoms, wherein volume averaging can be introduced over central targets and/or peripheral annuli of tissue, bone, and air. The algorithm is also demonstrated on actual CT brain scans but only for its qualitative effects. It is pointed out that higher order corrections, to be reported in future publications, will further correct the actual clinical scans.
Over-Reflection of Hydromagnetic Planetary Gravity Waves at the Solar Helmet Streamers and Magnetic Sectors

Over-reflection of propagating hydromagnetic planetary-gravity waves incident on the current sheets of the helmet streamers and magnetic sectors of the solar corona is investigated.
Marketing Academics' Perceptions of the Peer Review Process

Publication in refereed journals is critical to career success for most marketing faculty members, and the peer review process is the gatekeeper for a refereed journal. The study reported here examines marketing academics' perceptions of this peer review process. Based on responses from 653 marketing academics, we find favorable overall impressions of the review process as being fair/unbiased, truly double-blind, timely, and successful in improving the quality of research. But the process is not without concerns. In particular, there are concerns about the ability to have (and adhere to) a truly double-blind review process given the close-knit nature of the academy in conjunction with today's interconnected world. Problematically, researchers express dissatisfaction with the lack of timeliness in the review process. Given these concerns, we offer a strategically oriented recommendation for a code of publishing ethics and a tactically oriented recommendation focused on improvements in manuscript turnaround...
Cytochrome p450, Part 1: What Nurses Really Need to Know

Although knowledge about the impact of cytochrome p450 on individual variations in drug response has been known for decades, the transition to clinical practice has not evolved. Nurses who administer and prescribe medications have a responsibility to their patients to understand the responses to medications that are mediated by this family of enzymes. An overview of the variations seen in drug responses based on genetics is presented with discussion focusing on the current prescriptive practices and limitations in clinical drug trials.
Expertise and categorization

Experts exhibit various categorization phenomena, including category abstractness, use of second-order features, big chunks, category coherence, and category gradedness. Traditional views of categorization—the classical, prototype, and exemplar views—are variously successful in explaining these phenomena. We argue that our conceptual base view is more adequate.
Ion Movement in the Eye

The optical integrity and the metabolism of the eye depend on the exchange of substances between the blood vessels of the eye and the ocular chambers. The present paper considers the exchange of 3 ions in particular, i.e., sodium, chloride and bicarbonate, in the eye, with particular reference to the role of diffusion and active transport in determining the ionic composition of the various ocular fluids.
Impact of imaging measurements on response assessment in glioblastoma clinical trials

We provide historical and scientific guidance on imaging response assessment for incorporation into clinical trials to stimulate effective and expedited drug development for recurrent glioblastoma by addressing 3 fundamental questions: (i) What is the current validation status of imaging response assessment, and when are we confident assessing response using today's technology? (ii) What imaging technology and/or response assessment paradigms can be validated and implemented soon, and how will these technologies provide benefit? (iii) Which imaging technologies need extensive testing, and how can they be prospectively validated? Assessment of T1 +/− contrast, T2/FLAIR, diffusion, and perfusion-imaging sequences are routine and provide important insight into underlying tumor activity. Nonetheless, utility of these data within and across patients, as well as across institutions, are limited by challenges in quantifying measurements accurately and lack of consistent and standardized image acquisition parameters. Currently, there exists a critical need to generate guidelines optimizing and standardizing MRI sequences for neuro-oncology patients. Additionally, more accurate differentiation of confounding factors (pseudoprogression or pseudoresponse) may be valuable. Although promising, diffusion MRI, perfusion MRI, MR spectroscopy, and amino acid PET require extensive standardization and validation. Finally, additional techniques to enhance response assessment, such as digital T1 subtraction maps, warrant further investigation.
Pathologic Outcomes in Favorable-risk Prostate Cancer: Comparative Analysis of Men Electing Active Surveillance and Immediate Surgery

Abstract Background It remains unclear whether men selecting active surveillance (AS) are at increased risk of unfavorable longer term outcomes as compared with men who undergo immediate treatment. Objective To compare adverse pathologic outcomes in men with favorable-risk prostate cancer who underwent delayed prostatectomy after surveillance (DPAS) to those who elected immediate prostatectomy (IRP). Design, setting, and participants We conducted a retrospective analysis of a prospective AS registry from 2004 to 2014. From the Johns Hopkins AS program ( n =1298), we identified a subset of men who underwent DPAS ( n =89) and was representative of the entire cohort, not just those that were reclassified to higher risk. These men were compared with men who underwent IRP ( n =3788). Outcome measurements and statistical analysis We measured adverse pathologic features (primary Gleason pattern ≥4, seminal vesicle invasion [SVI], or lymph node [LN] positivity). Multivariable models were adjusted for age, prostate-specific antigen density, and baseline risk classification. Results and limitations Delayed prostatectomy occurred at a median of 2.0 yr (range: 0.6–9.0) after diagnosis. The DPAS and IRP cohorts demonstrated similar proportions of men with primary Gleason pattern ≥4 (17% vs 20%; p =0.11), SVI (3.3% vs 3.2%; p =0.53), LN positivity (2.3% vs 1.2%; p =0.37), and overall adverse pathologic features (21.3% vs 17.0%; p =0.32). The adjusted odds ratio of adverse pathology was 1.33 (95% confidence interval, 0.82–2.79; p =0.13) for DPAS as compared with IRP. Limitations include a modest cohort size and a limited number of events. Conclusions In men with favorable-risk cancer, the decision to undergo AS is not independently associated with adverse pathologic outcomes. Patient summary This report compares men with favorable-risk prostate cancer who elected active surveillance with those who underwent immediate surgery accounting for evidence that approximately one-third of men who choose surveillance will eventually undergo treatment. Our findings suggest that men who are closely followed with surveillance may have similar outcomes to men who elect immediate surgery, but additional research is needed.
Observation of pseudoelastic behavior in large Cu-Ni composite multilayer nanowires

In recent years, studies have shown that single crystal metallic nanowires (NWs) can exhibit unique pseudoelastic behavior when their cross-sectional area is smaller than a certain critical value, which is on the order of a few nms. The mechanism responsible for this behavior is the formation of partial dislocations (twinning). In this paper we demonstrate using molecular dynamics simulations that thicker composite nanowires can exhibit pseudoelastic behavior at large cross-sectional dimensions to 28 nm and higher, as long as the individual layer thickness do not exceed a critical value of 1.8-2 nm, thus making their manufacturing feasible and more attractive.
Efficient agent-based simulation framework for multi-node supercomputers

In recent years the importance of a large-scale Agent-based simulation (ABS) that can handle large complex systems is increasing. We developed a large-scale ABS framework on BlueGene, which is a multi-node supercomputer. The ABS processes the agents' communications. When the number of transmissions among the agents is large, the transmission costs seriously affect the performance of the simulation. It is possible to reduce the amount of transmission among the nodes by clustering the agents which communicate heavily with each other. Assuming that an agent is a graph node, and that a data transmission between agents is a graph edge, this problem can be formulated as a maximum-flow and minimum-cut problem. In this paper we present an efficient algorithm to find an approximate solution. Our algorithm is reliable, simple, and needs little computation. We demonstrate its beneficial effects with some experiments
Observing periodically forced systems of difference equations

We discuss the problem of determining the periodicity of the common driver of a system of periodically forced difference equations. Methods from topological reconstruction of attractors are applied to build a semiconjugacy to a topological version of the driver. A computational algorithm built from the semiconjugacy uses observations of the equation trajectories to isolate the driver period.
Anomalous electrical behavior of partially carbonized polyacrylonitrile fibers

Partially carbonized polyacrylonitrile fibers were observed to undergo a resistivity change of 2 to 4 orders of magnitude at a transition temperature typically in the range of 98 °C to 200 °C. The current-voltage curves exhibited an initial supercurrent-like increase, followed by a rapid drop to a high resistance state, and then a rise in current again at a later stage. These phenomena cannot be interpreted by existing theories on switching in inorganic amorphous semiconductors. They are explainable if the microstructure of the pyrolyzed fiber is viewed as comprising nanometer-scale superconducting phases interspersed with semiconducting phases, much like a large number of Josephson junctions connected in series.
A comparison of fluorescence in two sympatric scorpion species

In order to test the feasibility of scorpion fluorescence as an indicator of gender and/or species identity, a comparison of the fluorescence spectra between genders across two sympatric species of scorpions (Vaejovis confusus Stahnke 1940 and Paruroctonus shulovi Williams 1970) was conducted. Each spectrum was represented in a simple multivariate analysis by its peak wavelength and width at 90% of peak intensity. No difference between genders was found, but a statistically significant difference between species was detected. The potential of fluorescence as a basis for species recognition based on this difference is discussed in the context of what is known about scorpion vision and discriminatory abilities.
Hydrodynamic models for the RRc stars

SUMMARY Hydrodynamic pulsation models are constructed for the RR Lyrae stars, including a large grid of RRc models and a pair of models with parameters corresponding to the RRd stars. The latter calculations are used to argue that LNA periods are sufficient when comparing RRd models with observations. The RRc models are subjected to Fourier decomposition, and a discussion of various Fourier parameters is undertaken to complement a treatment given elsewhere of the phase parameter ¢31. It is shown that the theoretical light curves mimic the observations rather well, including the observed run of ¢31 with period and the fall-off of ¢31 with R 21 • The greatest deficiency of the models lies in their failure to reproduce observed values of the phase parameter ¢21. Finally, turning to the velocity curves, we show that the first-order phase lag (/)..¢)1 between velocity and light is related in the models to the linear driving 'YJ 1 and thus potentially may be used to measure the distances of observed RRc stars from their respective blue edges.
Type I STS markers are more informative than cytochrome B in phylogenetic reconstruction of the Mustelidae (Mammalia: Carnivora).

We compared the utility of five nuclear gene segments amplified with type I sequence-tagged site (STS) primers versus the complete mitochondrial cytochrome b (cyt b) gene in resolving phylogenetic relationships within the Mustelidae, a large and ecomorphologically diverse family of mammalian carnivores. Maximum parsimony and likelihood analyses of separate and combined data sets were used to address questions regarding the levels of homoplasy, incongruence, and information content within and among loci. All loci showed limited resolution in the separate analyses because of either a low amount of informative variation (nuclear genes) or high levels of homoplasy (cyt b). Individually or combined, the nuclear gene sequences had less homoplasy, retained more signal, and were more decisive, even though cyt b contained more potentially informative variation than all the nuclear sequences combined. We obtained a well-resolved and supported phylogeny when the nuclear sequences were combined. Maximum likelihood and Bayesian phylogenetic analyses of the total combined data (nuclear and mitochondrial DNA sequences) were able to better accommodate the high levels of homoplasy in the cyt b data than was an equally weighted maximum parsimony analysis. Furthermore, partition Bremer support analyses of the total combined tree showed that the relative support of the nuclear and mitochondrial genes differed according to whether or not the homoplasy in the cyt b gene was downweighted. Although the cyt b gene contributed phylogenetic signal for most major groupings, the nuclear gene sequences were more effective in reconstructing the deeper nodes of the combined tree in the equally weighted parsimony analysis, as judged by the variable-length bootstrap method. The total combined data supported the monophyly of the Lutrinae (otters), whereas the Melinae (badgers) and Mustelinae (weasels, martens) were both paraphyletic. The American badger, Taxidea taxus (Taxidiinae), was the most basal taxon. Because hundreds of type I STS primer sets spanning the complete genomes of the human and mouse have been published and thus represent many independently segregating loci, the potential utility of these markers for molecular systematics of mammals and other groups is enormous. (Cytochrome b; intron; Mammalia; Mustelidae; nuclear DNA; phylogeny; sequence-tagged sites.)
Noncytolytic Extraction of Murine Tumor-Specific Transplantation Antigens With the Nonionic Detergent Octyl-β-d-glucopyranoside

The nonionic detergent octyl-beta-D-glucopyranoside (C8Glu) was used to extract immunogenic tumor-specific transplantation antigen (TSTA) from intact cells and purified plasma membranes of the 3-methylcholanthrene-induced fibrosarcoma MCA-F. Pretreatment of syngeneic C3H/HeJ mice with 100 micrograms of C8Glu extracts induced specific immunoprotection such that mice resisted the outgrowth of MCA-F but not the antigenically distinct tumors MCA-D or MCA-2A. Incubation of intact cells with 7 mM (0.2%) C8Glu for 30 minutes at 23 degrees C was judged to be noncytolytic because extracted cells excluded trypan blue. Preparative isoelectric focusing partially purified the MCA-F-specific antigen from crude C8Glu extracts into the pH 6.5-6.8 region of the gradient. Electrofocusing yielded 60% of the applied antigen activity and a fourfold to fivefold increase in specific activity. In addition, immunoprotective activity was obtained in 2% C8Glu extracts of MCA-F plasma membranes, confirming the membrane localization of the MCA-FTSTA. Three properties of C8Glu rendered it an attractive agent for the preparation of cell surface proteins: a nonionic character, large critical micellar concentration, and its capacity to extract antigens without complete membrane solubilization or cell disruption.
Accelerated Experience-Dependent Pruning of Cortical Synapses in Ephrin-A2 Knockout Mice

Refinement of mammalian neural circuits involves substantial experience-dependent synapse elimination. Using in vivo two-photon imaging, we found that experience-dependent elimination of postsynaptic dendritic spines in the cortex was accelerated in ephrin-A2 knockout (KO) mice, resulting in fewer adolescent spines integrated into adult circuits. Such increased spine removal in ephrin-A2 KOs depended on activation of glutamate receptors, as blockade of the N-methyl-D-aspartate (NMDA) receptors eliminated the difference in spine loss between wild-type and KO mice. We also showed that ephrin-A2 in the cortex colocalized with glial glutamate transporters, which were significantly downregulated in ephrin-A2 KOs. Consistently, glial glutamate transport was reduced in ephrin-A2 KOs, resulting in an accumulation of synaptic glutamate. Finally, inhibition of glial glutamate uptake promoted spine elimination in wild-type mice, resembling the phenotype of ephrin-A2 KOs. Together, our results suggest that ephrin-A2 regulates experience-dependent, NMDA receptor-mediated synaptic pruning through glial glutamate transport during maturation of the mouse cortex.
Scalable analysis and design of ad hoc networks via random graph theory

We lay down the foundations of a new approach for the scalable analysis of ad hoc networks, with special regard to the properties of the random network topology. The proposed methodology is rooted in the theory of random graphs, but we significantly extend the conventional random graph model, as in its original form it would be too "sterile" to capture realistic ad hoc networks. We analyze some fundamental properties of the proposed new, general model and demonstrate that it is capable of solving analysis/design problems which would otherwise be difficult to capture.
A robust parallel implementation of 2D model-based recognition

An approach to 2D model-based object recognition is developed, suitable for implementation on a highly parallel SIMD (single-instruction, multiple data stream) computer. Object models and image data are represented as contour features. Transformation sampling is used to determine the optimal model-feature-to-image-feature transformation by sampling the space of possible transformations. Only a small part of this space need actually be sampled due to the constraints placed on transformations by individual matches of image features to model features. The procedure requires O(Kmn) processors and O(log/sup 2/ (Kmn)) time, where m is the number of model features, n is the number of image features, and K depends on the size of the image. The procedure works well and is extremely robust in the presence of occlusion. An implementation of the procedure on the Connection Machine is described, and some experimental results given. >
Many Readers but Few Followers: The Fate of Nicholas of Lyra's “Apocalypse Commentary” in the Hands of His Late-Medieval Admirers

“Use Auriol's Compendium as a mould, pour in Lyre, flavor with Augustine, and sprinkle with Grosseteste.” This was John Wyclif's (1330–1384) recipe for biblical commentary. It may be the nature of biblical commentary that commentators do not follow recipes closely, but the history of how the admirers of Nicholas of Lyra's Apocalypse Commentary (1329) received and reworked it indicates that Nicholas's work served frequently as the “mould” into which other interpretations were “poured,” while his own Augustinian seasonings were largely ignored. Although later commentators often adopted Nicholas's method, they more frequently poured in the ingredients of his younger Franciscan colleague, Peter Auriol (whose Apocalypse Commentary of 1319 Nicholas sharply critiqued), serving up a dish that Nicholas would not have enjoyed eating.
Addressable floating light activated micro-electrical stimulators for wireless neurostimulation

Stimulation of the central nervous system can be useful for treating neurological disorders. Wireless neurostimulating devices have the benefit that they can float in tissue and do not experience the sheering caused by tethering tension that non-wireless stimulators impose on connecting wires. An optically powered, logic controlled, CMOS microdevice that can decode telemetry data from an optical packet is a potential way of implementing wireless, addressable, microstimulators. Through the use of an optical packet, different devices can be addressed for stimulation, allowing spatially selective activation of neural tissue. This work presents the design and simulations of such a neural stimulation device, specifically an optically powered CMOS circuit that decodes telemetry data and determines whether it has been addressed.
Short-term repeatability of electrocardiographic P wave indices and PR interval

Abstract Background P wave indices and PR interval from 12-lead electrocardiograms (ECGs) are predictors of cardiovascular morbidity and mortality, but their repeatability has not been examined. Objectives Determine the short-term repeatability of P wave indices (P axis, maximum P area and duration, P dispersion and P terminal force in V1) and PR interval. Methods Participants (n = 63) underwent two standard ECGs at each of two visits, two weeks apart. We calculated the intra-class correlation coefficient (ICC), weighted kappa, and minimal detectable change and difference. Results ICCs were 0.93 for PR interval, 0.78 for P axis, 0.77 for maximum P area, and 0.58 for maximum P duration. Within- and between-visit Kappa were 0.30 and 0.11 for P dispersion, and 0.68 and 0.46 for P terminal force. Conclusion Repeatability of PR duration was excellent, that of P wave axis and maximum area was fair, and maximum P wave duration and terminal force was poor. Repeatability of P wave dispersion was fair within visit, yet poor between visits. These results illustrate potential biases when measurement error of some P wave indices is ignored in clinical and epidemiologic studies.
The Thematic Apperception Test as a diagnostic tool with retarded adults.

Projective techniques have been used with the mentally retarded for at least three major purposes: ( 1 ) diagnosis of personality in terms of inner feelings and needs; ( 2 ) evaluation of personality change after some form of therapy; and ( 3 ) assessment of kind and amount of organic brain damage. However, these uses of projective techniques have not gone unchallenged. Sarason (1949, p. 253), for example, regrets "that these procedures have received relatively uncritical acceptance," and Louttit (1957) has questioned the results obrained from the use of these tests with the mentally retarded on the basis of test validity. Delp's (1959) suggestion that tests are often misused if utilized in inappropriate situations, may be construed as a further criticism when coupled with the fact that nowhere in the manual (Murray, 1943, p. 4 ) of one of the most extensively used projective tests, the Thematic Apperception Test (TAT), is there any mention of the mentally retarded. A more recent criticism has been levied by Dingman, et al. ( 1960), "projective measures, while promising, have not shown the statistical promise that would lead one to invest the time in new norms." This study was an attempt to investigate the validity of these criticisms with regard to the use of projective techniques as a diagnostic tool in a relatively restricted area, namely, with mentally retarded adults seeking vocational rehabilitation. This was done, first by determining the quantity and quality of verbal output on the part of the retarded S, and then, by ascertaining the relationship between verbal output and age, sex, and intelligence. For the purpose of this study quantity is defined as the verbal output, i.e., the number of words produced by S. Quality refers to the coherence of S's verbal output without regard to the number of words in his story.
New Insights into the Pathogenesis of MDS and the rational therapeutic opportunities

Myelodysplastic syndromes (MDS) include a heterogeneous group of acquired hematopoietic malignancies characterized by ineffective hematopoiesis, peripheral cytopenias, and a varying propensity for progression to acute myeloid leukemia. The clinical heterogeneity in MDS is a reflection of its molecular heterogeneity. Better understanding of aberrant epigenetics, dysregulation of immune responses, and del(5q) MDS has provided the rationale for well-established treatments in MDS. Further understanding of abnormal signal transduction and aberrant apoptosis pathways has led to development of new rational therapies that are in advanced phases of clinical translation. This review seeks to describe recent developments in our understanding of the pathogenesis of MDS and the potential therapeutic implications of these observations.
Chlor-syngas: Coupling of Electrochemical Technologies for Production of Commodity Chemicals

This paper describes a novel electrolysis process called chlor-syngas, where synthesis gas is produced at the cathode and chlorine gas is produced at the anode. The work presented is an extension of previous electrolysis system development, where syngas was cathodically generated from water, CO2, and electricity. The process described here uses chloride-based electrolytes. Using HCl as the anolyte provides a low-cost source of Cl–, and leakage of excess protons lowers the catholyte pH, preventing carbonate buildup in the catholyte. Initial electrolysis data are presented here to demonstrate the feasibility of the process in KCl/KCl and KCl/HCl electrolytes. Using the electrolysis data, an estimation of the energetic and environmental benefits is presented. The process could be a path to a more sustainable chemical industry, where the starting materials are low-value or wastes from other related processes.
Effect of WY-5256 on Renal Hemodynamics

SummaryWY-5256 was administered to dogs to determine the effect of this agent on renal hemodynamics. Changes in renal hemo-dynamics were estimated with an electromagnetic flow meter in conjunction with clearances of p-aminohippurate (PAH) and inulin. It was observed that WY-5256 increased renal blood flow, that the increase was greater than that indicated by PAH calculated blood flow, and that increases in non-PAH extracting flow were greater in proportion than increases in PAH calculated blood flow. The effect of WY-5256 on renal function was also studied when renal blood flow was held constant with an aortic clamp. It was demonstrated that the drug increased sodium excretion in the absence of blood flow alterations. The increase was less than that seen without the clamp. These data are interpreted as indicating that this agent acts in part by directly inhibiting sodium reabsorption and in part by altering renal hemodynamics to increase sodium excretion.
U.S. v. Mehanna, the First Amendment, and Material Support in the War on Terror

This note examines the history of the right to free speech during wartime and the Material Support Statute in the War on Terror through the lens of the conviction of Tarek Mehanna. After examining the effect of the Material Support Statute on the right to free speech, this note will argue that a new incitement standard should be developed for speech which provides support for terrorism.
Molecular cloning, tissue distribution, and functional expression of the human Na(+)/H(+) exchanger NHE2.

In the present report, we describe the cloning of a human colonic cDNA that describes the full-length Na+/H+exchanger (NHE) 2 coding region. The human NHE2 (hNHE2) cDNA encodes for a polypeptide of...
Design Principles of DNA Enzyme-Based Walkers: Translocation Kinetics and Photoregulation.

Dynamic DNA enzyme-based walkers complete their stepwise movements along the prescribed track through a series of reactions, including hybridization, enzymatic cleavage, and strand displacement; however, their overall translocation kinetics is not well understood. Here, we perform mechanistic studies to elucidate several key parameters that govern the kinetics and processivity of DNA enzyme-based walkers. These parameters include DNA enzyme core type and structure, upper and lower recognition arm lengths, and divalent metal cation species and concentration. A theoretical model is developed within the framework of single-molecule kinetics to describe overall translocation kinetics as well as each reaction step. A better understanding of kinetics and design parameters enables us to demonstrate a walker movement near 5 μm at an average speed of ∼1 nm s–1. We also show that the translocation kinetics of DNA walkers can be effectively controlled by external light stimuli using photoisomerizable azobenzene moie...