cssi/SciSciGPT-SciSciNet huggingface dataset:
LIS-less neurons don't even make it to the starting gate.

The manuscript by Tsai et al. (935–945) is a tour de force analysis of a controversial issue in developmental neurobiology, namely the molecular basis of the devastating human brain malformation, type I lissencephaly (Lis1) (Jellinger, K., and A. Rett. 1976. Neuropadiatrie. 7:66–91). For several decades, defects in neuronal migration have been assumed to underlie all defects in cortical histogenesis. In the paper by Tsai et al., the authors use a variety of elegant approaches, including the first real-time imaging of cortical neurons with reduced levels of LIS1, to demonstrate that LIS1 and dynactin act as regulators of dynein during cortical histogenesis. A loss of LIS1 results in both a failure to exit the cortical germinal zone and abnormal neuronal process formation. Thus, the primary action of the mutation is to disrupt the production of neurons in the developing brain as well as their migration.
Nonlinear cyclic response of laminated glass FRP tubes filled with concrete

Fiber reinforced polymer (FRP) materials are generally known for their linear elastic response to failure. The present study evaluated the implications of using FRP as primary and sole reinforcement for concrete structures in seismic regions through an experimental and analytical investigation on the cyclic response of two different types of laminated glass FRP tubes filled with concrete. The study showed that concrete-filled tubes can be designed with an appropriate laminate structure for a ductility level comparable to that of conventional reinforced concrete columns. The nonlinearity and ductility in these types of structures stem from the off-axis response of the FRP tube. A hysteretic model was developed for the tube, and was cast into a two-dimensional three-node combined fiber element for the concrete-filled FRP tube. Good agreement was shown between the analytical models and the experimental results.
Behavioral intervention technologies: Evidence review and recommendations for future research in mental health.

Abstract Objective A technical expert panel convened by the Agency for Healthcare Research and Quality and the National Institute of Mental Health was charged with reviewing the state of research on behavioral intervention technologies (BITs) in mental health and identifying the top research priorities. BITs refers to behavioral and psychological interventions that use information and communication technology features to address behavioral and mental health outcomes. Method This study on the findings of the technical expert panel. Results Videoconferencing and standard telephone technologies to deliver psychotherapy have been well validated. Web-based interventions have shown efficacy across a broad range of mental health outcomes. Social media such as online support groups have produced disappointing outcomes when used alone. Mobile technologies have received limited attention for mental health outcomes. Virtual reality has shown good efficacy for anxiety and pediatric disorders. Serious gaming has received little work in mental health. Conclusion Research focused on understanding reach, adherence, barriers and cost is recommended. Improvements in the collection, storage, analysis and visualization of big data will be required. New theoretical models and evaluation strategies will be required. Finally, for BITs to have a public health impact, research on implementation and application to prevention is required.
Privacy practices of Internet users: self-reports versus observed behavior

Several recent surveys conclude that people are concerned about privacy and consider it to be an important factor in their online decision making. This paper reports on a study in which (1) user concerns were analysed more deeply and (2) what users said was contrasted with what they did in an experimental e-commerce scenario. Eleven independent variables were shown to affect the online behavior of at least some groups of users. Most significant were trust marks present on web pages and the existence of a privacy policy, though users seldom consulted the policy when one existed. We also find that many users have inaccurate perceptions of their own knowledge about privacy technology and vulnerabilities, and that important user groups, like those similar to the Westin "privacy fundamentalists", do not appear to form a cohesive group for privacy-related decision making.In this study we adopt an experimental economic research paradigm, a method for examining user behavior which challenges the current emphasis on survey data. We discuss these issues and the implications of our results on user interpretation of trust marks and interaction design. Although broad policy implications are beyond the scope of this paper, we conclude by questioning the application of the ethical/legal doctrine of informed consent to online transactions in the light of the evidence that users frequently do not consult privacy policies.
Role of Plc1p in regulation of Mcm1p-dependent genes

In budding yeasts, phosphoinositide-specific phospholipase C (Plc1p encoded by PLC1 gene) and several inositol polyphosphate kinases represent a nuclear pathway for synthesis of inositol polyphosphates (InsPs), which are involved in several aspects of DNA and RNA metabolism, including transcriptional regulation. Plc1p-produced inositol trisphosphate (InsP3) is phosphorylated by Ipk2p/Arg82p to yield InsP4/InsP5. Ipk2p/Arg82p is also a component of ArgR-Mcm1p complex that regulates transcription of genes involved in arginine metabolism. The role of Ipk2p/Arg82p in this complex is to stabilize the essential MADS box protein Mcm1p. Consequently, ipk2Δ cells display reduced levels of Mcm1p and attenuated expression of Mcm1p-dependent genes. Because plc1Δ cells display aberrant expression of several groups of genes, including genes involved in stress response, the objective of this study was to determine whether Plc1p also affects expression of Mcm1p-dependent genes. Here we report that not only ipk2Δ, but also plc1Δ cells display decreased expression of Mcm1p-dependent genes. However, Plc1p is not involved in stabilization of Mcm1p and affects transcription of Mcm1p-dependent genes by a different mechanism, probably involving regulation of chromatin remodeling complexes.
Prinzmetal's work and the “Sclarovsky-Birnbaum ischemia score” for acute myocardial infarction: a parallel in systematizing electrocardiographic knowledge

In this viewpoint, the author traces back in time the original (? if possible) description of the electrocardiographic hallmarks of myocardial ischemic injury leading to myocardial infarction. In this venture, he detects a parallel between the work of Prinzmetal et al and that of Sclarovsky and Birnbaum and al, in their approach to research, which is based on systemization and utilization of electrocardiographic knowledge.
A multiple-map strateby for interpolated mapping

Abstract The method of Interpolated Mapping is extended to a multi-map strategy to systematically reduce the error in numerical determinations of a non-linear system's time evolution. The degree of state space distortion that the mapping must contend with is limited by the use of this approach, thus smoothing the short-term system dynamics that the interpolation procedure has to approximate. Global basins of attraction are determined and their associated fractal dimension calculated to illustrate the advantages of the multi-map strategy over the basic Interpolated Mapping technique. Also, the deformation of state space and the effects of both high and low distortion are illustrated as an aid to visualizing the system dynamics and encouraging the development of the multi-map approach.
Survey for pesticides in wells associated with apple and peach orchards in West Virginia

In a five-year study of rural wells in Ontario, Canada, pesticide contamination resulted from: i) back-siphoning of spray solution, 2) spills at the mixing site, and~or 3) spray drift or surface runoff from field application (Frank et al. 1987). Out of 40 wells with suspected contamination from pesticides used in orchards, on tobacco or on vegetables, one shallow well contained phosmet residues resulting † surface runoff following application in an orchard (Frank et al. 1987). A spill of 1,2-dibromo-3-chloropropane (DBCP) † a rusty can caused the contamination of a well associated with a South Carolina peach orchard (Carter et al. 1984).
A conditional likelihood ratio test for order restrictions in exponential families

Abstract This paper considers a conditional likelihood ratio procedure for testing order restrictions on a collection of parameters indexing a set of populations from an exponential family. The class of problems dealt with here has received detailed examination in earlier work of Robertson and Wegman (1978). The conditional test amounts to a modification of the likelihood ratio procedure developed by those authors; it benefits from increased statistical power, at least for interesting classes of alternative hypotheses, and in addition, is computationally less burdensome than the likelihood ratio method. A Monte Carlo comparison of the power of the conditional and unconditional tests is carried out. An application to testing trend in a set of Poisson parameters is discussed.
Synthesis of double-labeled lactosylceramide

The total stereo-controlled synthesis of lactosylceramide and introduction of two kinds of isotopes,3H and14C, into synthetic lactosylceramide are described.
Rank-based variable selection

This note considers variable selection in the robust linear model via R-estimates. The proposed rank-based approach is a generalisation of the penalised least-squares estimators where we replace the least-squares loss function with Jaeckel's (1972) dispersion function. Our rank-based method is robust to outliers in the errors and has roots in traditional non-parametric statistics for simple location-shift problems. We establish the theoretical properties of our estimators which ensure desirable asymptotic behaviour of setting coefficient estimates to zero for unimportant variables and consistently estimating coefficients for important variables. Numerical studies indicate that the rank-based methods perform well for both light- and heavy-tailed error distributions.
Differential regulation of the superoxide dismutase family in experimental aortic aneurysms and rat aortic explants.

Objective Oxidative stress has been implicated in abdominal aortic aneurysm pathogenesis. This study sought to characterize the relevance of superoxide dismutases (SOD), a family of reactive oxygen catalyzing metalloenzymes, including manganese SOD (MnSOD), copper-zinc SOD (CuZnSOD), and extracellular SOD (EcSOD), in a rodent aortic aneurysm model. Methods Male rat infrarenal abdominal aortas were perfused with either saline (control) or porcine pancreatic elastase (6 U/mL). Aortic diameter was measured and aortas harvested on post-operation days 1, 2, and 7 (N = 5–6 per treatment group per day). MnSOD, CuZnSOD, EcSOD, catalase, MMP-2, MMP-9, and β-actin expression in aortic tissue was determined by quantitative real-time PCR. MnSOD protein levels were measured using western immunoblotting and immunohistochemistry. In subsequent experiments, aimed at understanding the mechanism by which SOD is involved in AAA pathogenesis, rat aortic explants (RAEs) were incubated in media for 24 h in the presence of interleukin-1β (IL-1β, 2 ng/mL) and TEMPOL (SOD mimetic), catalase, or a combined SOD and catalase mimetic. Media MMP-2 and MMP-9 activity was determined by zymography. Data were analyzed by Student’s t-tests and ANOVA. Results Elastase-perfused aortic diameters were significantly increased compared to control aortas by post-perfusion day 7 (P = 0.016). MnSOD mRNA levels in elastase perfused aortas were 6.0 (P = 0.05) and 7.5 times (P Conclusion Experimental abdominal aortic aneurysm formation is associated with early increases in MnSOD expression and an increase in MMP-9 activity. Strategies aimed at inhibiting oxidative stress during AAA formation should focus on MnSOD.
NUCLEAR MOTION CORRECTIONS TO THE BINDING ENERGY IN HYDROGEN. AN EFFECTIVE POTENTIAL APPROACH.

Most of the calculations of nuclear recoil corrections to the atomic binding in hydrogen have been done using the covariant Bethe-Salpeter equation. In this paper an alternative to the Bethe-Salpeter approach in the form of a modified Dirac equation is presented. It contains the usual Hamiltonian for an electron in the field of a static proton, but it also includes the proton's kinetic energy and an interaction term due to transverse photons. The part of the interaction which produces the hyperfine splitting is extracted and treated perturbatively, whereas the remainder of the potential is retained, rearranged, and approximated in such a way as to make the resulting equation soluble. In a simple way, we are able to obtain reduced mass corrections to the fine structure and the hyperfine structure of hydrogen. An extension of the work, which enables us to calculate additional recoil terms not included in our lowest order effective potential, is briefly described.
Regularized Inversion of Correlation Functions in Dynamic Light Scattering

A linear regularized technique, requiring no a priori information, is described for the inversion of correlation data obtained from dynamic light scattering measurements of polymer/colloidal suspensions. The procedure allows the determination of the characteristic linewidth distribution function, which is normally the first step towards obtaining a particle size distribution.
Symmetry of iteration graphs

We examine iteration graphs of the squaring function on the rings ℤ/nℤ when n = 2kp, for p a Fermat prime. We describe several invariants associated to these graphs and use them to prove that the graphs are not symmetric when k = 3 and when k ⩾ 5 and are symmetric when k = 4.
Investigation of DUSP8 and CALCA in alcohol dependence

Evidence for genetic linkage to alcohol dependence was found on chromosome 11p15.5 from an autosome-wide scan in a Southwestern Native American population. The purpose of this study was to identify genes that may underlie this linkage signal. Two genes, calcitonin/calcitonin-related polypeptide alpha (CALCA) and dual specificity phosphatase 8 (DUSP8), met our criteria for candidacy, and were sequenced to identify polymorphisms that may be relevant to disease. Both genes play a role in various pathways known to underlie the pathophysiological mechanisms leading to development of alcohol dependence. While no polymorphisms were found in CALCA, four novel polymorphisms were found in DUSP8, one of which led to an amino acid substitution. Genotyping of this functional variant in 463 Southwestern Native Americans revealed no significant association between the DUSP8 C712T (Ala193Val) polymorphism and alcohol dependence (odds ratio = 1.48 95% CI 0.6-3.92).
Secondary organic aerosol from biogenic volatile organic compound mixtures

The secondary organic aerosol (SOA) yields from the ozonolysis of a Siberian fir needle oil (SFNO), a Canadian fir needle oil (CFNO), and several SOA precursor mixtures containing reactive and non-reactive volatile organic compounds (VOCs) were investigated. The use of precursor mixtures more completely describes the atmosphere where many VOCs exist. The addition of non-reactive VOCs such as bornyl acetate, camphene, and borneol had very little to no effect on SOA yields. The oxidation of VOC mixtures with VOC mass percentages similar to the SFNO produced SOA yields that became more similar to the SOA yield from SFNO as the complexity and concentration of VOCs within the mixture became more similar to overall SFNO composition. The SOA yield produced by the oxidation of CFNO was within the error of the SOA yield produced by the oxidation of SFNO at a similar VOC concentration. The SOA yields from SFNO were modeled using the volatility basis set (VBS), which predicts the SOA yields for a given mass concentration of mixtures containing similar VOCs.
The Schmuzers and the Rococo Transformation of Mediaeval Churches in Bavaria

There are instances in many periods of the transformation of older churches by drastic remodeling or recasing of their exteriors or interiors. These are sometimes pregnant examples of stylistic change. In its early development, even at its initiation, a new style may be markedly influenced by the problems imposed by the preexisting physical structure. As regards exteriors, one thinks of Alberti's Tempio Malatestiano at Rimini. There the earlier mediaeval walls were entirely hidden by new front and side facades that all but adumbrated the High Renaissance more than a generation avant la lettre. In the preceding century the transformation of the Norman choir in Gloucester cathedral by a reticulated grid of molded mullions and transoms, covering evenly both the old broad piers and the openings between, certainly marked a major advance in the early development of the Perpendicular.
Two characterizations of newtonian potential

The sufficient conditions in some propositions of Newton's about gravitation are shown to be necessary also. The problem is expounded in §1, the principal results are presented in §§3, 4, 9, and 10.
A hybrid Schrödinger/Gaussian beam solver for quantum barriers andsurface hopping

In this paper, we propose a hybrid method coupling a Schrodinger solver and the Gaussian beam method for the numerical simulation of quantum tunneling through potential barriers or surface hopping across electronic potential energy surfaces. The idea is to use a Schrodinger solver near potential barriers or zones where potential energy surfaces cross, and the Gaussian beam method--which is much more efficient than a direct Schrodinger solver--elsewhere. Buffer zones are used to convert data between the Schrodinger solver and the Gaussian beam solver. Numerical examples show that this method indeed captures quantum tunneling and surface hopping accurately, with a computational cost much lower than a direct quantum solver in the entire domain.
A concurrent development tool for flexible assembly systems

Global competition and the rapid pace of technological change now require the almost continual introduction of product upgrades by any manufacturer. Thus, such a manufacturer is likely to market older and newer versions of a product simultaneously, not to mention niche-specific editions of any product upgrade. An increasingly successful response to this product proliferation is the implementation of flexible assembly systems. In the context of a flexible assembly system (FAS), the ability to estimate the impact of various product and process options on the maximal level of system output becomes crucial to managing the ever-changing product mix. This paper presents a tool for such impact estimation that can facilitate concurrent development and engineering. Experience with an actual FAS is the basis for the reported results. The tool is a specialized combination of discreteevent computer simulation, experimental design, and regression analysis. Application of the tool assumes FAS use with a cellular manufacturing philosophy. Thus, uncluttered process flow for a family of products in the sense of group technology places the focus on potential bottlenecks. The new tool here models the impact of process and product options on bottleneck and, hence, FAS behavior.
Fine particle concentrations and composition during wintertime inversions in Logan, Utah, USA

Abstract During Winter 2004, a series of elevated PM2.5 events occurred in Logan, Utah, coinciding with strong winter inversions. This period resulted in 17 exceedances of the 24-h PM2.5 standard, and some of the highest PM2.5 mass loadings recorded in the United States, including 9 days of 24-h PM2.5 measurements over 100 μg m−3. During the 3-month period, we monitored the size and mass concentrations of airborne particles using an aerosol mass spectrometer. PM2.5 concentrations were dominated by the formation of ammonium nitrate, accounting for over 50% of the non-refractory aerosol matter throughout the study and 80% on the highest pollution days. Another 15–20% of the particulate matter was composed of organic carbon. The high particle concentration loadings in Utah's Cache Valley result from a combination of unfavorable meteorology dominated by a severe cold-temperature inversion, a mix of rural and urban emission sources, and a confined geographical area. As a rapidly growing formerly rural area, the Cache Valley is representative of future air pollution problems facing areas of the interior west undergoing rapid urbanization.
On Making Behavioral Genetics Truly Developmental

What will it take to make behavioral genetics truly developmental? In my opinion, the purely statistical population view will have to be abandoned in favor of the study of individuals: An analysis of
SEQUENCE TYPING CONFIRMS THAT CAMPYLOBACTER JEJUNI STRAINS ASSOCIATED WITH GUILLAIN‐BARRÉ AND MILLER‐FISHER SYNDROMES ARE OF DIVERSE GENETIC LINEAGE, SEROTYPE, AND FLAGELLA TYPE

Guillain-Barre syndrome (GBS) and Miller-Fisher syndrome (MFS) are correlated with prior infection by Campylobacter jejuni in up to 40% of cases. Nucleotide sequence-based typing of 25 C. jejuni isolates associated with neuropathy permitted robust comparisons with equivalent data from approximately 800 C. jejuni isolates not associated with neuropathy. A total of 13 genetic lineages and 20 flaA short variable region nucleotide sequences were present among the 25 isolates. A minority of isolates (4 of 25) had the flaA short variable region nucleotide sequences that were previously proposed as a marker for GBS-associated isolates. These 4 isolates probably represented the Penner serotype 19 lineage, which has been proposed to have an association with GBS.
Abstract 687: Variations in promoter methylation levels of DNA repair genes and breast cancer risk in the New York site of the Breast Cancer Family Registry.

Reduced DNA repair capacity contributes to genomic instability, a hallmark of carcinogenesis. The link between DNA repair capacity and cancer is especially relevant in breast cancer, where women with suboptimal repair capacity have been reported to have up to a five-fold increase in breast cancer risk compared to women with better repair capacity. We investigated promoter methylation levels of DNA repair-related genes and their association with breast cancer risk among participants of the New York site of the Breast Cancer Family Registry, comparing sisters affected with breast cancer to their unaffected sisters. We analyzed DNA extracted from viable mononuclear cells from 218 sisters (N=538 women) using pyrosequencing assays designed to target CpG islands in the promoter regions of BRCA1, MSH2, and MLH1. Breast cancer risk was not significantly associated with the promoter methylation level of BRCA1 (OR=1.09 [0.98-1.20]), MLH1 (OR=1.18 [0.90-1.54]) or MSH2 (OR=0.87 [0.47-1.59]). We assessed the Spearman correlation between methylation and previously generated data on expression level of BRCA1 and MSH2, where we had observed a significant increase in breast cancer risk among women in the lowest quartile of expression for MSH2. Among the affected women, no significant correlation was observed between methylation and expression level for MSH2 (-0.04, p=0.39) or BRCA1 (r=-0.05, p=0.39). These findings suggest that while MSH2 may have implications for breast cancer risk, as suggested by the previously observed increase in risk with decrease in expression level of MSH2, the lack of an association between gene promoter methylation levels of MSH2 and breast cancer risk and the lack of a correlation with expression level in the current study, indicate that other mechanisms impacting the reduction in expression level of this gene may be more relevant to explain the observed increase in breast cancer risk. Citation Format: Maya A. Kappil, Mary Beth Terry, Yuyan Liao, Regina Santella. Variations in promoter methylation levels of DNA repair genes and breast cancer risk in the New York site of the Breast Cancer Family Registry. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 687. doi:10.1158/1538-7445.AM2013-687
Singularity and stratification theory applied to dynamical systems

Transversality theory is a basic technical and theoretical tool in the study of smooth mappings, dynamical systems and bifurcation theory. In this paper we describe a version of transversality theory applicable to the study of maps and vector fields which are equivaxiant under the smooth action of a compact Lie group G. From a local point of view, we will be outlining a theory for the analysis of solutions of symmetric equations. From the global point of view, we will be describing an intersection theory for G-manifolds. The foundational theory of transversality for G-manifolds was developed in the mid 1970’s by Bierstone ’ and the author lo. The focus of Bierstone’s work was on extending Mather’s theory of stable mappings to smooth equivariant maps. As part of that program, Bierstone extended Thom’s jet transversality theorem to equivariant maps ’. On the other hand, Field’s motivation was to extend parts of the Smale program to equivariant dynamical systems ll. Much later it turned out that techniques of equivariant transversality had powerful applications to equivariant bifurcation theory 16712-14. Very recently there have also been applications to equivariant reversible systems * and equivariant Hamiltonian systems 6 . In this paper, we emphasize applications of equivariant transversality to the
Microcathode Thruster $(\mu\hbox{CT})$ Plume Characterization

An experimental observation of microcathode thruster plasma plume is described. An effect of the magnetic field on the plume expansion is considered. Two observation techniques are employed--charge-coupled-device camera and the concentric Langmuir probe. It is found that magnetic field significantly affects the plasma plume, and the strong magnetic field can lead to hollow plume formation.
Response to Various Amounts of Aspergillus oryzae Fermentation Extract on Ruminal Metabolism in Cattle

The objective of this study was to determine whether Aspergillus oryzae fermentation extract stimulated or inhibited ruminal fermentation when fed at higher than recommended doses (3 g/d). Four dietary treatments of A. oryzae fermentation extract were fed daily to six cows fitted with ruminal cannulas. For each of four periods, bromegrass hay (6% CP) with and without extract was fed for 28 d. Dacron bags containing bromegrass cell walls were ruminally incubated to determine ruminal fiber degradation. The A. oryzae fermentation extract did not affect degradation of cell walls, cellulose, or hemicellulose. Total ruminal anaerobic or cellulolytic bacteria were not different among treatments; neither were the proportions of cellulolytic species, Butyrivibrio sp., Ruminococcus albus, or Ruminococcus flavefaciens. Ruminal ammonia was not different; however, total VFA were higher, and pH tended to be lower, when 27 g/d of A. oryzae fermentation extract was fed. The proportion of VFA was not different among treatments. The A. oryzae fermentation extract fed at nine times the recommended dosage did not produce any stimulatory effects, except for total VFA, and was not inhibitory or toxic to ruminal metabolism and forage fiber degradation.
Mechanisms of vasorelaxation induced by eicosapentaenoic acid (20:5n‐3) in WKY rat aorta

The vasorelaxant activity of eicosapentaenoic acid (EPA, 20:5n-3), the omega-3 polyunsaturated fatty acid, was investigated in isolated Wistar Kyoto (WKY) rat aortae by measuring isometric tension. Eicosapentaenoic acid (1–100 μM) relaxed rat aortae contracted with high K+ (80 mM) or noradrenaline (NA, 1 μM) in a concentration-dependent manner. Contractions induced by Bay K 8644 or increasing concentrations of calcium were unaffected by EPA. The relaxant effect of EPA (3–100 μM) was significantly inhibited by indomethacin (10 μM), the cyclo-oxygenase inhibitor, but not by the nitric oxide (NO) synthesis inhibitor, Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME, 100 μM). Removal of the endothelium did not alter EPA-induced relaxations. In Ca2+-free, EGTA 2 mM solution, EPA (10–30 μM significantly inhibited NA-sustained contractions. Incubation with EPA (5, 10 μM) diminished both NA-induced (1 μM) phasic and sustained contractions. The vasorelaxant effects of EPA (30 μM) on NA-induced (1 μM) contractions were significantly inhibited by the K+ channel blocker, glibenclamide (10 μM), but not tetraethylammonium (1 mM). Moreover, indomethacin and glibenclamide combined significantly inhibited EPA-induced (1–100 μM) responses. These results indicate EPA exerts its endothelium-independent vasorelaxant effects in WKY rat aortae through production of prostanoids which activate K+ATP channels. Inhibition of Ca2+ mobilization from intracellular pools and influx through the non-L-type, but not the L-type, Ca2+ channel are also possible mechanisms action of EPA's. British Journal of Pharmacology (2000) 131, 1793–1799; doi:10.1038/sj.bjp.0703754
Collection functions for non-equivivant cell populations.

Abstract T. T. Puck has introduced and used the collection function for the study of a cellular population growing exponentially in vitro and then subjected to colcemide block. A rigorous derivation of his results is given in an earlier paper ( Trucco, 1965c ), but only for the case of equivivancy. (This means that the duration of a phase (G1, S, G2 or M) is the same for every cell in the population.) The present note deals with the case in which the distributions of sojourn times in each phase are characterized by probability density functions that depend only on cellular age. Using the age density functions, the following quantities can be computed: N(t), the total number of cells in the population as a function of time, and N(m)(t), the number of cells that are in mitosis. Furthermore, if tritiated thymidine is added to the culture as well as colcemide, expressions are derived for the number of labeled cells, L(t), and for the number of labeled mitoses, L(m)(t). In the case of equivivancy the results of this paper coincide with those obtained previously.
Effects of Prey Deprivation on Life Table Attributes of Neoseiulus idaeus Denmark and Muma (Acari: Phytoseiidae)

Abstract Reproductive responses of Neoseiulus (= Amblyseius) idaeus Denmark and Muma ovipositing females were measured under three dietary regimes consisting of Mononychellus tanajoa (Bondar) or Oligonychus gossypii (Zacher) combined with specific periods (24, 48, 72, and 96 h) of starvation or periods of the same duration in which only cassava exudate was provided. These periods were applied after the females had laid at least one egg. The control treatments consisted of predators supplied with a continuous diet of either M. tanajoa or O. gossypii. Ovipositional period and survival were prolonged with prey deprivation. Following a period of prey deprivation, ovipositional rates recovered to the same or higher level than those of the control. Depending on the regime, females could withstand periods of 24 to 72 h prey deprivation without reducing their reproductive potential. Exudate feeding helped females to withstand periods of prey deprivation by sustaining their maintenance metabolism, and allowing a high reproductive potential to be maintained for extended periods. It was shown that oviposition was not chronological age-dependent but physiological age (measured as past egg production)-dependent and that, during periods of food shortage, resources were allocated primarily to maintenance at the expense of reproduction. Neither the sex ratio nor the hatching success of the progeny were affected by starvation.
Estimation of the Guarantee Time in an Exponential Failure Model

The location parameter ? in a 2-parameter exponential failure model is often termed the guarantee time since no failure can occur until the life exceeds ?. Several point estimators of ? are compared by examining each estimator's risk corresponding to a loss function which features a greater penalty for overestimating than for underestimating ?. The estimators considered in this fashion are: maximum likelihood, minimum variance unbiased, best invariant, and median unbiased. A new estimator of ? is derived which has smaller risk under our assumptions than any of the aforementioned estimators. A 2-fold pairwise comparison technique is then used which examines a) the odds in favor of the new estimator's being closer to ? than is a competitor, and b) each estimator's risk not only when it is closer to ? than is the other but also when it is not.
Mutation of putative GRK phosphorylation sites in the cannabinoid receptor 1 (CB1R) confers resistance to cannabinoid tolerance and hypersensitivity to cannabinoids in mice.

For many G-protein-coupled receptors (GPCRs), including cannabinoid receptor 1 (CB1R), desensitization has been proposed as a principal mechanism driving initial tolerance to agonists. GPCR desensitization typically requires phosphorylation by a G-protein-coupled receptor kinase (GRK) and interaction of the phosphorylated receptor with an arrestin. In simple model systems, CB1R is desensitized by GRK phosphorylation at two serine residues (S426 and S430). However, the role of these serine residues in tolerance and dependence for cannabinoids in vivo was unclear. Therefore, we generated mice where S426 and S430 were mutated to nonphosphorylatable alanines (S426A/S430A). S426A/S430A mutant mice were more sensitive to acutely administered delta-9-tetrahydrocannabinol (Δ9-THC), have delayed tolerance to Δ9-THC, and showed increased dependence for Δ9-THC. S426A/S430A mutants also showed increased responses to elevated levels of endogenous cannabinoids. CB1R desensitization in the periaqueductal gray and spinal cord following 7 d of treatment with Δ9-THC was absent in S426A/S430A mutants. Δ9-THC-induced downregulation of CB1R in the spinal cord was also absent in S426A/S430A mutants. Cultured autaptic hippocampal neurons from S426A/S430A mice showed enhanced endocannabinoid-mediated depolarization-induced suppression of excitation (DSE) and reduced agonist-mediated desensitization of DSE. These results indicate that S426 and S430 play major roles in the acute response to, tolerance to, and dependence on cannabinoids. Additionally, S426A/S430A mice are a novel model for studying pathophysiological processes thought to involve excessive endocannabinoid signaling such as drug addiction and metabolic disease. These mice also validate the approach of mutating GRK phosphorylation sites involved in desensitization as a general means to confer exaggerated signaling to GPCRs in vivo.
Diffusion/perfusion MR imaging of acute cerebral ischemia.

In vivo echo-planar MR imaging was used to measure apparent diffusion coefficients (ADC) of cerebral tissues in a comprehensive noninvasive evaluation of early ischemic brain damage induced by occlusion of the middle cerebral artery (MCA) in a cat model of acute regional stroke. Within 10 min after arterial occlusion, ADC was significantly lower in tissues within the vascular territory of the occluded MCA than in normally perfused tissues in the contralateral hemisphere. Sequential echo-planar imaging was then used in conjunction with bolus injections of the magnetic susceptibility contrast agent, dysprosium DTPA-BMA, to characterize the underlying cerebrovascular perfusion deficits. Normally perfused regions of brain were identified by a dose-dependent 35–70% loss of signal intensity within 6–8 s of contrast administration, whereas ischemic regions appeared relatively hyperintense. These data indicate that sequential diffusion/perfusion imaging may be diagnostically useful in differentiating permanently damaged from reversibly ischemic brain tissue. © 1991 Academic Press, Inc.
Export agriculture is feeding malaria: a cross-national examination of the environmental and social causes of malaria prevalence

Malaria rates remain high across many less-developed regions, including Southeast Asia, Sub-Saharan Africa, and parts of Latin America. Although case studies find elevated malaria rates in locales with increased levels of environmental degradation, the current body of comparative environmental research lacks investigation of infectious disease trends. This study draws upon world-system theorizing to consider agricultural export flows and resulting alterations to the natural environment in poor nations as key causes of malaria prevalence. Additionally, relationships among world-system position, economic development, and socio-health characteristics are examined alongside the environmental predictors using structural equation modeling for data on 99 less-developed nations. The findings emphasize that deforestation and biodiversity loss associated with primary sector export flows are key drivers of malaria rates, alongside notable influences of basic health and social services. The results suggest that environmental and social conditions greatly shape malaria transmission in poor societies.
Devolatilization wave structures and temperatures for the pyrolysis of polymethylmethacrylate, ammonium perchlorate, and coal at combustion level heat fluxes

Abstract Data are presented for the surface pyrolysis temperatures, T s , and for the develatilization mass loss rate per unit area, ṁ, for polymethylmethacrylate (PMMA) exposed to a laser beam at incident flux levels of 15–500 W/cm 2 . After a brief induction time during which the surface is being heated to T s , the measured ṁ values are thereafter steady state in time, and are linearly related to the net absorbed flux, I abs . The measured values for ṁ are in good agreement with that derived from the first law of thermodynamics: m = I abs ∫ T s T o C(T) dT+δ H v (T s ) −1 Kinetically, this equation represents a devolatilization wave front whose propagation rate and maximum temperature are both heat transport controlled, and determined by the magnitude of the driving flux, I abs . The available data for ammonium perchlorate and for coal are also shown to obey a similar relationship, and the same heat transport-controlled process appears to govern their pyrolysis and devolatilization kinetics. At high fluxes, the measured ṁ and T s values reported here for PMMA, and those reported by other investigators, can be interrelated to one another through an Arrhenius plot whose slope gives an “activation energy” that is essentially equal to the heat of vaporization, ΔH v ( T s ). That measured relationship between ṁ and T s is thus a reflection of the Clausius-Clapeyron equation for the equilibrium vapor flux emanating from the polymer melt at its surface decomposition temperature, T s . However, at low fluxes, the measured ṁ values are significantly lower than those predicted by the Clausius-Clapeyron line. The departure is attributed to the additional presence of mass transport limitations. Photographic data are presented for bubble structure and bubble location within the quenched PMMA samples that independently confirm the increasing significance of mass transport limitations at the lower fluxes.
Exact property of the autocorrelation function of a conserved spin component.

An exact property of the autocorrelation function of a conserved spin component is established. Standard approximate forms of the spin autocorrelation function (power law, exponential, Gaussian) do not have this property.
Negotiating rare book purchases

L'A. donne quelques recommandations aux bibliothecaires charges des acquisitions pour negocier au mieux les achats de livres rares et de collections specialisees. La mise en place d'une strategie en interne doit preceder les transactions avec les vendeurs.
Using Social Network Analysis to Investigate the Potential of Innovation Networks: Lessons Learned from NASA's International Space Apps Challenge

Abstract This research analyzes the affiliated multipartite social networks of hackathon style mass collaboration events. Using social network analysis we model the innovation networks for NASA's International Space Apps Challenge and use social network analysis to understand the structure of and relationships within the modeled networks. Using metrics such as degree, degree distribution, degree correlations, and density, the resulting models and study answer questions like: can social network statistics act as indicators of innovation performance within a network and which statistics provide insight to the likelihood of innovation performance? We address these research questions by building the affiliation networks for the 2012 and 2013 NASA International Space Apps Challenges and applying Gnyawali and Srivastava's conceptual model on cluster and network effects against these real-world networks to empirically prove the likelihood of innovation.
Protection from venous air embolism with fluorocarbon emulsion FC-43.

Intraoperative venous air embolism (VAE) occurs frequently in some surgical settings and may cause devastating hemodynamic consequences. Perfluorocarbon emulsions have been investigated as artificial oxygen carrying medias. They also have the properties of enhanced nitrogen solubility and a small particle size. FC-43 (Oxypherol, Alpha Therapeutic Corp., Los Angeles, California) was compared to three other volume expanders in 91 New Zealand White laboratory rabbits exposed to continuous VAE. The animals were anesthetized and ventilated by one of four modalities. They then received one of the volume expanders at 20 cc/kg over 30 min. After a 10-min stabilization period, a constant femoral venous air infusion (0.25 cc/kg/min) was begun and continued until death. Time until death, total volume of air infused, femoral arterial pressure, central venous pressure, and ECG (Lead II) were recorded. Death was defined as the cessation of pulsatile blood pressure. Arterial and central venous gases were analyzed pre and post volume expansion and at intervals of every 5 min after the beginning of the femoral air infusion. Results showed a significant prolongation of life for the animals receiving FC-43 at 10 and 20 cc/kg as a volume expander and mechanically ventilated with 100% oxygen as compared to all other groups (P < 0.05). PaO2 and PvO2 were consistently higher in the group receiving FC-43 as a volume expander. Central venous pressure was lower during air embolism in the FC-43 group. The mechanism for the enhanced survivability of rabbits pretreated with FC-43 volume expansion exposed to VAE is under further investigation.
Fine-Needle Aspiration Cytology of Hemangiopericytoma A Report of Five Cases

BACKGROUND Hemangiopericytoma (HPC) is a relatively rare neoplasm, accounting for approximately 2.5% of all soft tissue tumors. Its histopathology has been well documented but to the authors' knowledge reports regarding its fine-needle aspiration (FNA) cytology rarely are encountered. In the current study the authors report the cytologic findings in FNA specimens from nine confirmed cases of HPC and attempt to correlate the cytologic features with the biologic outcomes. METHODS FNA was performed with or without radiologic guidance. Corresponding sections of tissue were reviewed in conjunction with the cytologic preparations. RESULTS Nine FNAs were performed in 5 patients (3 men and 2 women) with an age range of 38–77 years (mean, 56 years). Two lesions were primary soft tissue lesions arising in the lower extremities; seven were recurrent or metastatic lesions from bone (one lesion), kidney (one lesion), pelvic fossa (one lesion), lower extremities (two lesions), trunk (one lesion), and breast (one lesion). All aspirates were cellular and were comprised of single and tightly packed clusters of oval to spindle-shaped cells aggregated around branched capillaries. Basement membrane material was observed in 6 cases (67%). The nuclei were uniform and oval, with finely granular chromatin and inconspicuous nucleoli in all cases except one. No mitotic figures or areas of necrosis were identified. A correct diagnosis of HPC was made on one primary lesion and all recurrent or metastatic lesions. CONCLUSIONS HPCs show a spindle cell pattern in cytologic preparations and must be distinguished from more common spindle cell lesions. The presence of branched capillaries and abundant basement membrane material supports a diagnosis of HPC. Immunohistochemistry and electron microscopy performed on FNA samples may be helpful in the differential diagnosis. FNA is a useful and accurate tool with which to confirm recurrent or metastatic HPC; however, prediction of the biologic behavior of HPC based on cytologic features is not feasible. Cancer (Cancer Cytopathol) 1999;87:190–5. © 1999 American Cancer Society.
Role of folate antagonists in the treatment of methicillin-resistant Staphylococcus aureus infection

Methicillin-resistant Staphylococcus aureus (MRSA) infection has reached epidemic proportions, and therapeutic options are limited because these strains are often multidrug resistant. However, the new strains of community-acquired MRSA show decreased resistance to trimethoprim-sulfamethoxazole. Clinical and experimental reports show a mixture of successes and failures with trimethoprim-sulfamethoxazole treatment. A reason for failure might be the amount of thymidine released from damaged host tissues and bacteria, a concept strengthened by the fact that S. aureus thermonuclease releases thymidine from DNA. Thus, success or failure with trimethoprim-sulfamethoxazole may well depend on the amount of tissue damage and organism burden, rather than acquisition of a resistance gene. Clinical trials and experimental animal studies show high failure rates, perhaps because of released thymidine. The use of trimethoprim-sulfamethoxazole for community-acquired MRSA infection should not be endorsed without further research.
Comparison of indications for aortic valve replacement in 1978 and in 1988

Abstract Aortic valve diseases constitute the majority of valvular heart diseases requiring valve replacement in the United States. During the past 3 decades, surgical replacement of the aortic valve has become the treatment of choice for a variety of aortic valve diseases. 1 The etiologies of aortic valvular lesions requiring surgery have also changed considerably over the past several decades. For instance, with the decreasing incidence of clinical acute rheumatic fever in the western world, a decline in postinflammatory aortic stenosis (AS) has already been observed based on pathologic studies. 2,3 Concomitantly, there has been a gradual increase in the number of patients with degenerative calcific AS undergoing valve replacement. 4 This retrospective study was undertaken to determine changes in the clinical indications leading to aortic valve replacement and the etiologies of underlying valvular pathology in a university hospital in 1978 and 1988.
A Comparison of Rhythm Pattern Perception and Performance in Normal and Learning-Disabled Readers, Age Seven and Eight

While the passage of Public Law 94–142 has increased the mainstreaming of exceptional children in general music classes, little research has been conducted to determine if these children learn musi...