cssi/SciSciGPT-SciSciNet huggingface dataset:
Inactivation and resynthesis of glucosamine-6-phosphate synthetase after treatment with glutamine analogs.

Abstract The biosynthesis of D-glucosamine-6-phosphate by l -Glutamine: d -fructose-6-phosphate aminotransferase in the liver of the rat is irreversibly inactivated by injection of N-acetyl-6-diazo-5-oxo- l -norleucine, Duazomycin A. The course of inactivation parallels the disappearance of UDP-N-acetyl-hexosamine from the liver. Injection of glucosamine with Duazomycin A completely protects the enzyme against inactivation, without protecting enzymes involved in the biosynthesis of purine and cytosine nucleotides that are sensitive to Duazomycin A. The injection of glucosamine either 2 or 4 hr after Duazomycin A reduces the lag in appearance of aminotransferase activity without altering the ultimate rate of what appears to be resynthesis, since the process is inhibited by puromycin and dl -ethionine; the time required to regain 50% of the activity is 13 to 20 hr. Crude and partially purified extracts containing the aminotransferase are irreversibly inactivated by either Duazomycin A or 6-diazo-5-oxo- l -norleucine; the rate of inactivation by the latter is dependent upon its concentration over the range 1 × 10 −6 to 3 × 10 −4 m (K m = 8 × 10 −5 m ) . Both l -glutamine and UDP-N-acetylglucosamine reduce the rate of inactivation of the enzyme by 6-diazo-5-oxo- l -norleucine in vitro; a combination of both compounds is more effective than either alone, and evidence is presented that the two protective compounds act at different sites on the enzyme. The protective effects have been demonstrated in a crude extract and with a partially purified enzyme. Glucose-6-phosphate, fructose-6-phosphate and other amino sugars and nucleotide compounds related to UDP-N-acetyl-glucosamine do not protect against inactivation by 6-diazo-5-oxo- l -norleucine. The protective effect of UDP-N-acetylglucosamine in vitro appears to explain the protective effect of glucosamine in vivo. The implications of these findings are discussed with respect to the nature of the interaction between the enzyme, its two substrates, its feedback inhibitor (UDP-N-acetylglucosamine) and the inactivator, 6-diazo-5-oxo- l -norleucine. This system provides a means of studying the synthesis of a specific constitutive enzyme under controlled conditions in the liver.
Five Readers Browsing: The Reading Interests of Talented Middle School Boys.

Researchers concerned with curriculum differentiation for gifted and talented students have long promoted the benefits of providing opportunities for students to explore their personal interests within the regular curriculum. Many literacy researchers have also concluded that teachers can improve students’ (especially boys’) attitudes toward reading by offering opportunities within the literacy curriculum for students to choose reading materials based on their own personal interests. However, there are few empirical investigations into the particular interests of talented boy readers to guide teachers who wish to provide students with a rich selection of texts from which to choose. In this multicase study, 5 boys who are talented readers were observed while they browsed for reading materials in a large bookstore. Interviews with each boy and analysis of the texts that they identified as personally interesting revealed 4 major themes that together characterize the complexity of these boys’ reading preferences.
Density functionals for the energy of electronic systems: Explicit variational construction.

A nonlinear transformation performs the Levy-constrained search formulation of the density functional for the electronic energy through a minimization of the energy with respect to a set of variational coefficients. The construction requires a complete set of arbitrary functions as the auxiliary basis. Truncation of the basis set provides an upper bound to the energy functional. Practical approaches to obtain accurate upper bounds to this functional are discussed, and a density-functional alternative to the standard Hartree-Fock method is described.
Characterization of the adaptation response of Anacystis nidulans to growth in the presence of sublethal doses of herbicide

Cells of the cyanobacterium,Anacystis nidulans, were cultured in the presence of sublethal doses of the herbicides DCMU [3-(3,4-dichlorophenyl)-1, 1-dimethylurea] and terbutryn (a triazine). The responses observed were characteristic of photosynthetic organisms grown under low light conditions. The contents of the accessory pigment phycocyanin increased in relation to chlorophyll. Moreover, each dose of herbicide was correlated with defined changes in the pigment profile. Data obtained from chlorophyll fluorescence measurements indicated that the additional phycocyanin was functionally integrated into phycobilisomes, probably into newly formed phycobilisomes. The concentration of fatty acids in the total polar lipid fraction (per milligram chlorophyll) was greater in adapted than in control cells; nevertheless, the ratio of unsaturated to saturated fatty acids remained unchanged. Measurable rates of photosynthetic electron transport were similar among herbicide-adapted cultures and controls. These data are consistent with the hypothesis that herbicide treatment impaired electron transport, but that function was restored by the adaptation response. Furthermore, this response is conserved among cyanobacteria and higher plants, indicating that this flexibility is extremely significant to photosynthetic function.
Neonatal treatment with testosterone proprionate or diethylstilbestrol alters sex differentiation of 5α-reductase and 16α-hydroxylase

Neonatal exposure to testosterone appears to determine the normal programming of certain hepatic enzyme activities, perhaps via the aromatization of testosterone to estrogens in the brain. These studies examine whether neonatal exposure to testosterone propionate (TP) or diethylstilbestrol (DES) alters the normal programming of hepatic 16α-hydroxylase (using [4-14C]-androstenedione as substrate) or 5α-reductase (using [4-14C]-testosterone as substrate). In normal adult rats, 16α-hydroxylase is higher in male liver, while 5α-reductase is higher in female liver. Neonatal administration of TP or DES to intact animals produce decreases in adult male 16α-hydroxylase (feminization). Levels of 16α-hydroxylase in resultant adult females and 5α-reductase activity levels in adult male and female rats were unaffected by neonatal TP or DES treatment. Treatment of neonatal rats with DES but not TP results in significantly reduced circulating androgen levels. Therefore, feminized levels of 16α-hydroxylase do not correlate with serum androgen levels. Neonatal castration of male rats on day 1 results in feminization of 16α-hydroxylase and 5α-reductase activities in adult animals. TP or DES treatment on day 2 did not reverse the effect of neonatal castration. These studies demonstrate that the hormonal regulation of the hepatic steroid metabolizing enzymes, 5α-reductase and 16α-hydroxylase, is different. 16α-hydroxylase appears to be more sensitive to neonatal hormonal modulation than is 5α-reductase.
The long QT syndrome in children. An international study of 287 patients.

BACKGROUNDThe Pediatric Electrophysiology Society studied children with the long QT syndrome (LQTS) to describe the features of LQTS in patients less than 21 years old, define potential "low-risk" and "high-risk" subpopulations, and determine optimal treatment.METHODS AND RESULTSPatients less than 21 years old were included if either QTc was more than 0.44; they had unexplained syncope, seizures, or cardiac arrest preceded by emotion or exercise; or family history of LQTS. We found 287 patients from 26 centers in seven countries. Mean +/- SD age at presentation was 6.8 +/- 5.6; 9% presented with cardiac arrest, 26% with syncope, and 10% with seizures. Of those with symptoms, 67% had symptoms related to exercise. Family history was positive for long QT interval in 39% and for sudden death in 31%. Hearing loss was present in 4.5%. A normal QTc was present in 6%, and QTc of more than 0.60 was in 13%. Atrioventricular block occurred in 5%, but 13 of 15 patients had second-degree atrioventricular block (2:1), ...
Monothiol CGFS Glutaredoxins and BolA-like Proteins: [2Fe-2S] Binding Partners in Iron Homeostasis

Monothiol glutaredoxins (Grxs) with a signature CGFS active site and BolA-like proteins have recently emerged as novel players in iron homeostasis. Elegant genetic and biochemical studies examining the functional and physical interactions of CGFS Grxs in the fungi Saccharomyces cerevisiae and Schizosaccharomyces pombe have unveiled their essential roles in intracellular iron signaling, iron trafficking, and the maturation of Fe-S cluster proteins. Biophysical and biochemical analyses of the [2Fe-2S] bridging interaction between CGFS Grxs and a BolA-like protein in S. cerevisiae provided the first molecular-level understanding of the iron regulation mechanism in this model eukaryote and established the ubiquitous CGFS Grxs and BolA-like proteins as novel Fe-S cluster-binding regulatory partners. Parallel studies focused on Escherichia coli and human homologues for CGFS Grxs and BolA-like proteins have supported the studies in yeast and provided additional clues about their involvement in cellular iron metabolism. Herein, we review recent progress in uncovering the cellular and molecular mechanisms by which CGFS Grxs and BolA-like proteins help regulate iron metabolism in both eukaryotic and prokaryotic organisms.
Discharge patterns in two crevasses of the Mississippi River Delta

Abstract This report evaluates variables which control water discharge in Rattlesnake Crevasse and, to a lesser extent, Little Lake Pond Crevasse, in the Mississippi River Delta. Multiple-regression and analysisof-variance procedures assess the spatial and temporal interaction and changes in intensity of the variables. River stage, local drainage conditions, semi-monthly tide, diurnal tide, and wind are factors which determine discharge patterns in these two delta crevasses. The discharge of Rattlesnake and Little Lake Pond crevasses complements that of the primary distributaries of the Mississippi River Delta. During flooding tide, when seaward flow is inhibited in delta distributaries, the two crevasses attain maximum discharge. Flow in Rattlesnake Crevasse reverses direction during moderate and low river stages.
Molecular recognition using motion of molecules under Coulomb's Law

The molecular recognition problem (or the docking problem) can be formulated as follows: given two rigid molecules, find their relative orientation with the maximum number of ''contacts'' or ''peak'' interaction energy. For this purpose, we propose (1) removal of internal atoms, (2) special distribution of ''charges'' among retained atoms, (3) motion of the molecules (without internal atoms) as rigid bodies under a special Coulomb's Law. This approach is different from previous methods [see 1-4 and the references therein].
Fluorescence polarization sensing

We describe a new approach to fluorescence sensing based on fluorescence polarization measurements. The sensing device consists of an analyte sensitive fluorescence probe and a reference fluorophore which is not affected by the analyte. Combined emission from probe and reference passes through two adjacent orthogonally oriented polarizers and is viewed with second analyzer polarizer. Changes in the probe intensity result in changes in the polarization of the combined emission. The analyzer polarizer is rotated to yield equal intensity from both sides of two orthogonally oriented polarizers. So constructed sensor earlier was used for manual visual detection of RhB in intralipid and to measure pH using 6-carboxyfluorescein. A sensor equipped with the simple electronic detection system of a dual photocell and a Watson bridge improves the accuracy. We used this device with UV hand lamp, electroluminescent light source or LED to detect pH, oxygen and calcium. This sensing method is generic and can be used with any fluorophore which displays an analyte-dependent change in intensity.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Intakes of long-chain omega-3 (n−3) PUFAs and fish in relation to incidence of asthma among American young adults: the CARDIA study

Background: Although long-chain ω-3 (n−3) PUFAs (LCω3PUFAs) have been linked to the prevention of some inflammatory disorders, little is known about the association between these fatty acids and incidence of asthma. Objective: The objective was to prospectively investigate the association between LCω3PUFAs and fish intake and incidence of asthma among American young adults. Design: A 20-y follow-up longitudinal analysis was conducted in a biracial cohort of 4162 Americans, aged 18–30 y, with a history of asthma at baseline in 1985. Diet was assessed by a validated interviewer-administered quantitative food-frequency questionnaire at the examinations in 1985, 1992, and 2005. Incident self-reported asthma was defined as having a physician diagnosis of asthma and/or the use of asthma medications between 1985 and 2005. Results: During the 20-y follow-up, 446 incident cases of asthma were identified. LCω3PUFA intake was significantly inversely associated with incidence of asthma after adjustment for sociodemographic, major lifestyle, and dietary confounders. The multivariable-adjusted HR for the highest quintile of LCω3PUFA intake as compared with the lowest quintile was 0.46 (95% CI: 0.33, 0.64; P-trend < 0.01). However, a higher frequency of nonfried fish consumption was not significantly associated with the risk of asthma. DHA showed a greater inverse association than did EPA. The association between LCω3PUFAs and incident asthma was not appreciably modified by sex, race, BMI, smoking status, or atopic status. Conclusion: This study showed that intakes of LCω3PUFAs are inversely longitudinally associated with the incidence of asthma in American young adults.
Commentary: The Human Genome: philosopher's stone or magic wand?

The commentary by Buchanan et al. 1 in this issue provides a candid assessment of our progress in the search for genetic determinants of complex diseases. Geneticists, physicians, and especially epidemiologists should take note. In the authors’ evaluation, human genome research has been disappointing, yielding few results with a positive impact on public health. Are the authors correct in their assessment? We need to critically evaluate the points raised by Buchanan et al. 1 and consider the practical suggestions that they offer. One useful framework for exploring the themes presented by Buchanan et al. 1 would be to identify two separate goals (among many others) for research in human genomics. First, there is the search for genetic causes of complex diseases. This immense effort serves as the flagship project for discovery science, an exciting and ever-expanding research programme ‘in which one generates large resources of information on biologic molecules in aggregate without necessarily knowing in advance which pieces of information and which correlations will prove most important’ [p. 34 in Ref. (2)]. Epidemiologists have embraced the search for genetic risk factors and are devoting enormous time, effort, and money to the enterprise. Detailed haplotype structures and tag SNPs now make it possible for epidemiologists to conduct genome-wide association studies using DNA collected from persons with and without disease. 4 Although many researchers recommend caution, 3
Uncertainty of calculated risk estimates for secondary malignancies after radiotherapy.

Purpose: The significance of risk estimates for fatal secondary malignancies caused by out-of-field radiation exposure remains unresolved because the uncertainty in calculated risk estimates has not been established. This work examines the uncertainty in absolute risk estimates and in the ratio of risk estimates between different treatment modalities. Methods and Materials: Clinically reasonable out-of-field doses and calculated risk estimates were taken from the literature for several prostate treatment modalities, including intensity-modulated radiotherapy (IMRT), and were recalculated using the most recent risk model. The uncertainties in this risk model and uncertainties in the linearity of the dose-response model were considered in generating 90% confidence intervals for the uncertainty in the absolute risk estimates and in the ratio of the risk estimates. Results: The absolute risk estimates of fatal secondary malignancy were associated with very large uncertainties, which precluded distinctions between the risks associated with the different treatment modalities considered. However, a much smaller confidence interval exists for the ratio of risk estimates, and this ratio between different treatment modalities may be statistically significant when there is an effective dose equivalent difference of at least 50%. Such a difference may exist between clinically reasonable treatment options, including 6-MV IMRT versus 18-MV IMRT for prostate therapy. Conclusion: The ratio of the risk between different treatment modalities may be significantly different. Consequently risk models and associated risk estimates may be useful and meaningful for evaluating different treatment options. The calculated risk of secondary malignancy should be considered in the selection of an optimal treatment plan.
Russian Peasants in the Factory 1892–1904

The character and revolutionary potential of Russian factory labor in the early phases of industrialization have been a source of controversy for over two generations. While no longer a matter of the utmost consequence, the problems of analysis and the conclusions involved in this debate have retained their significance not only for the study of the Russian revolutions but also for our contemporary experience with labor in underdeveloped countries. The following pages, dealing with the crucial years around 1900, intend to apply a modern approach to an ancient subject, starting with the question of the relationship between peasants and workers in the Russian factories and advancing to the problem of the “exploitation” of the workers by the “capitalists.”
Acetylation regulates the differentiation‐specific functions of the retinoblastoma protein

The retinoblastoma tumor-suppressor protein (pRb) is known to induce growth arrest and cellular differentiation. The molecular determinants of pRb function include protein–protein interactions and post-translational modifications such as phosphorylation. Recently, the co-activator p300 was found to acetylate pRb. The biological significance of pRb acetylation, however, remains unclear. In the present study, we provide evidence that pRb undergoes acetylation upon cellular differentiation, including skeletal myogenesis. In addition to p300, the p300-Associated Factor (P/CAF) can mediate pRb acetylation as pRb interacts directly with the acetyltransferase domain of P/CAF in vitro and can associate with P/CAF in differentiated cells. Significantly, by using a C terminal acetylation-impaired mutant of pRb, we reveal that acetylation does not affect pRb-dependent growth arrest or the repression of E2F transcriptional activity. Instead, acetylation is required for pRb-mediated terminal cell cycle exit and the induction of late myogenic gene expression. Based on these results, we propose that acetylation regulates the differentiation-specific function(s) of pRb.
ON THE EMERGENCE OF INTELLIGENT GLOBAL BEHAVIORS FROM SIMPLE LOCAL ACTIONS

Artificial Intelligence focuses on the question of how to design system to exhibit intelligent behaviour in complex environments. Complex global behaviours can emerge from simple systems acting in a complex environment; however, this emergence requires that the systems' internal structure reflect essential structures in the environment. This paper examines the algebraic structure of a system's actions. We find that these actions often possess a self-similar local neighborhood structure that permits analysis and synthesis to be performed locally yet produce global, intelligent behaviours. A procedure for finding this local structure is presented, and illustrated with examples.
The mirror focus and secondary epileptogenesis.

Publisher Summary Morrell coined the term secondary epileptogenesis and subsequently referred to it as the mirror focus. He demonstrated that following the creation of an epileptic primary focus, an independent epileptic focus can develop in the homotopic area of the contralateral hemisphere—that is, that region to which the primary focus sends a direct synaptic projection. In its early stages of development, this secondary epileptic zone is dependent on the integrity of the corpus callosum and subcortical connections. When in the mirror focus (“matures”), abolition of the primary focus, or section of the corpus callosum and/or interruption of subcortical connections, does not abolish the secondary epileptic zone. Thus, for the development of the mirror focus both callosal direct and subcortical polysynaptic connections are necessary; interruption of either during the formation of the mirror focus prevents its development. The secondary epileptic or mirror focus is a “pure culture” of epileptic neurons, uncontaminated by the agent used for creating the primary lesion or by the kindling electrode introduced into the primary site. In addition to serving as a model of epileptogenesis, the development of a secondary mirror focus has been used to investigate underlying mechanisms of information transfer and storage. Morrell devoted much of his research to the study of the synthesis of macromolecules (RNA and DNA) and the lasting changes in synaptic organization that occur during the development of secondary epileptic foci.
Sequencing of idiopathic pulmonary fibrosis-related genes reveals independent single gene associations.

Background Previous studies investigating a genetic basis for idiopathic pulmonary fibrosis (IPF) have focused on resequencing single genes in IPF kindreds or cohorts to determine the genetic contributions to IPF. None has investigated interactions among the candidate genes. Objective To compare the frequencies and interactions of mutations in six IPF-associated genes in a cohort of 132 individuals with IPF with those of a disease-control cohort of 192 individuals with chronic obstructive pulmonary disease (COPD) and the population represented in the Exome Variant Server. Methods We resequenced the genes encoding surfactant proteins A2 ( SFTPA2 ), and C ( SFTPC ), the ATP binding cassette member A3 ( ABCA3 ), telomerase ( TERT ), thyroid transcription factor ( NKX2-1 ) and mucin 5B ( MUC5B ) and compared the collapsed frequencies of rare (minor allele frequency MUC5B promoter variant that is over-represented in individuals with IPF. Results We found 15 mutations in 14 individuals (11%) in the IPF cohort: ( SFTPA2 (n=1), SFTPC (n=5), ABCA3 (n=4) and TERT (n=5)). No individual with IPF had two different mutations, but one individual with IPF was homozygous for p.E292V, the most common ABCA3 disease-causing variant. We did not detect an interaction between any of the mutations and the MUC5B promoter variant. Conclusions Rare mutations in SFTPA2 , SFTPC and TERT are collectively over-represented in individuals with IPF. Genetic analysis and counselling should be considered as part of the IPF evaluation.
The Decline and Resurgence of Congressional Party Conflict

Studies of party conflict on roll-call votes emphasize the political and structural contexts for party voting. Postwar congressional parties also worked in a macroeconomic policy context. Party conflict diminished when either unemployment or inflation was an isolated problem as the parties converged toward Keynesian solutions. The collapse of Keynesian notions in the stagflation of the 1970s stimulated party conflict. An examination of all budget-related roll-call votes in the House of Representatives from 1947 to 1990 shows that congressional party conflict has political, structural, and macroeconomic roots. To explain the level of party conflict, analysts must place parties in the context of major political settlements like that of the 1930s.
Genetic Approaches to the Study of Protease Function and Proteolysis in Saccharomyces cerevisiae

In the yeast Saccharomyces cerevisiae, proteases have been implicated in septum formation (Ulane and Cabib 1976), sporulation (Chen and Miller 1968; Hopper et al. 1974; Klar and Halvorson 1975; Betz and Weiser 1976; Zubenko and Jones 1981), protein turnover (Lopez and Gancedo 1979; Hansen et al. 1977), catabolite inactivation (Hagele et al. 1978; Neeff et al. 1978; Funayama et al. 1980; Holzer 1976; Jusik et al. 1976; Molano and Gancedo 1974; Magni et al. 1977; Magni et al. 1978), carbon starvation-induced degradation of NADP-dependent glutamate dehydrogenase (Hemmings and Mazon 1979; Mazon and Hemmings 1979), nitrogen starvation-induced degradation of NAD-dependent glutamate dehydrogenase (Hemmings 1980), enzyme secretion (Perlman and Halvorson 1981), localization of mitochondrial enzymes (Neupert and Schatz 1981), processing of enzyme precursors (Hemmings et al. 1981; Hasilik and Tanner 1978a, Jones et al. 1981; Zubenko et al. 1981), production of the pheromone α factor (J. Kurjan and I. Herskowitz 1982; D. Julius, A. Brake, L. Blair, and J. Thorner, personal communication), destruction of α factor (Maness and Edelman 1978; Ciejek and Thorner 1979; Ciejek 1980) and degradation of missense proteins (Donahue and Henry 1981) and nonsense fragments (Bigelis and Burridge 1978; Bigelis and Fink 1981).
Analytical derivatives, forces, force constants, molecular geometries, and related response properties in electronic structure theory

Analytical calculation of energy derivatives with respect to nuclear coordinates revolutionized applied molecular quantum mechanics by allowing the routine calculation of molecular structures and related properties. The cost of calculating first derivatives (gradients, forces) is comparable to the calculation of the energy for most electronic structure methods. Thus analytical differentiation, compared to numerical one, increases efficiency by a factor proportional to the number of nuclei and greatly improves numerical accuracy. Coordinate derivatives, together with their generalizations to electric and magnetic perturbations, are crucial for the determination of transition states, vibrational frequencies, infrared and Raman intensities, non-Born–Oppenheimer couplings, and magnetic properties: NMR spectra, magnetizability, vibrational circular dichroism, etc. Derivative theory, unlike perturbation theory, generally requires perturbation-dependent basis sets. The inclusion of contributions originating from this dependence is a better alternative than using the Hellmann–Feynman theorem with an extended basis set. Analytical second derivatives, compared to the numerical differentiation of first derivatives, do not yield savings similar to first derivatives versus energy, in accordance with Wigner's 2n + 1 rule, but still improve greatly efficiency and numerical accuracy. Third and fourth derivatives have also been implemented for simpler wavefunctions. Analytical gradients were initially formulated for variational wavefunctions. It was realized only later that the penalty for nonvariational wavefunctions is modest. The Lagrangian formulation provides a simple, elegant framework for general derivative theory. Disadvantages of analytical derivatives are increased code complexity, and, particularly for higher derivatives, the requirement of large blocks of computer time and memory, both of which may interfere with code parallelization.
The use of hybrid negotiation in resource coordination among agents

In this paper, we present a coordination strategy using a hybrid negotiation mechanism for multi-agent systems. The particular application is distributed resource allocation among agents. Agents adaptively coordinate resource among themselves to handle possible resource shortage crises resulted from dynamic events they encounter in an uncertain environment. The hybrid negotiation mechanism combines cooperative and competitive negotiations. Agents learn and make decisions on when to negotiate, with whom to negotiate, and how to negotiate based on the past negotiation experiences, current activities, and predictions. We have implemented a scalable system for the sustenance resource allocation among agents based on the hybrid negotiation mechanism.
Optimal Time of Day and the Magnitude of Age Differences in Memory

Across two studies comparing younger and older adults, age differences in optimal performance periods were identified (Study 1), and then shown to be an important determinant of memory differences (Study 2). A norming study showed that while most younger adults were Evening or Neutral types, as determined by a standard questionnaire, the vast majority of older adults were Morning types. A second study compared the recognition performance of younger and older adults tested in the morning or in the late afternoon. Substantial age differences were found in the late afternoon, when younger but not older adults were at their optimal times. However, no age differences in memory performance were found in the morning, when older but not younger adults were at their peak period. Thus, synchrony between optimal performance periods and the time at which testing is conducted may well be a critical variable in determining group differences in intellectual performance, particularly between older and younger adults.
Cdc42, Rac1, and Rac2 Display Distinct Patterns of Activation during Phagocytosis

The small G proteins Cdc42, Rac1, and Rac2 regulate the rearrangements of actin and membrane necessary for Fcγ receptor-mediated phagocytosis by macrophages. Activated, GTP-bound Cdc42, Rac1, and Rac2 bind to the p21-binding domain (PBD) of PAK1, and this interaction provided a basis for microscopic methods to localize activation of these G proteins inside cells. Fluorescence resonance energy transfer-based stoichiometry of fluorescent chimeras of actin, PBD, Cdc42, Rac1, and Rac2 was used to quantify G protein activation relative to actin movements during phagocytosis of IgG-opsonized erythrocytes. The activation dynamics of endogenous G proteins, localized using yellow fluorescent protein-labeled PBD, was restricted to phagocytic cups, with a prominent spike of activation over an actin-poor region at the base of the cup. Refinements of fluorescence resonance energy transfer stoichiometry allowed calculation of the fractions of activated GTPases in forming phagosomes. Cdc42 activation was restricted to the leading margin of the cell, whereas Rac1 was active throughout the phagocytic cup. During phagosome closure, activation of Rac1 and Rac2 increased uniformly and transiently in the actin-poor region of phagosomal membrane. These distinct roles for Cdc42, Rac1, and Rac2 in the component activities of phagocytosis indicate mechanisms by which their differential regulation coordinates rearrangements of actin and membranes.
Common coupling as a measure of reuse effort in kernel-based software with case studies on the creation of MkLinux and Darwin

An obstacle to software reuse is the large number of major modifications that frequently have to be made as a consequence of dependencies within the reused software components. In this paper, common coupling is categorized and used as a measure of the dependencies between software components. We compared common coupling in three operating systems, Linux, FreeBSD, and Mach, and related it to the reuse effort of these systems. The measure is evaluated by studying the creation of two operating systems, MkLinux which is based on the reuse of Linux and Mach, and Darwin which is based on the reuse of FreeBSD and Mach. We conclude that the way that common coupling is implemented in Linux kernel induces large dependencies between software components, which required more effort in order to be reused to produce MkLinux, while the common coupling implemented in the Mach and FreeBSD kernels induces few dependencies between software components, which required less effort in order to be reused to produce Darwin.
Radiation oncology in skin cancer treatment

Radiation was first used to treat a patient with squamous cell carcinoma of the nose in 1900. Following the development of improved dermatologic and surgical techniques in the 1950s, the role for radiation in the treatment of skin cancer gradually decreased.1 However, there remain certain settings in which radiation offers advantages over other currently available modalities. The goals of this chapter are to review the current indications for the use of radiation in the treatment of skin cancer, the techniques commonly employed in modern radiotherapy, the role of radiation in the treatment of specific skin malignancies, and the complications that arise from the use of radiation to treat skin cancers.
Prediction and analysis of nucleosome exclusion regions in the human genome

Nucleosomes are the basic structural units of eukaryotic chromatin, and they play a significant role in regulating gene expression. Specific DNA sequence patterns are known, from empirical and theoretical studies, to influence DNA bending and flexibility, and have been shown to exclude nucleosomes. A whole genome localization of these patterns, and their analysis, can add important insights on the gene regulation mechanisms that depend upon the structure of chromatin in and around a gene. A whole genome annotation for nucleosome exclusion regions (NXRegions) was carried out on the human genome. Nucleosome exclusion scores (NXScores) were calculated individually for each nucleotide, giving a measure of how likely a specific nucleotide and its immediate neighborhood would impair DNA bending and, consequently, exclude nucleosomes. The resulting annotations were correlated with 19055 gene expression profiles. We developed a new method based on Grubbs' outliers test for ranking genes based on their tissue specificity, and correlated this ranking with NXScores. The results show a strong correlation between tissue specificity of a gene and the propensity of its promoter to exclude nucleosomes (the promoter region was taken as -1500 to +500 bp from the RefSeq-annotated transcription start site). In addition, NXScores correlated well with gene density, gene expression levels, and DNaseI hypersensitive sites. We present, for the first time, a whole genome prediction of nucleosome exclusion regions for the human genome (the data are available for download from Additional Materials). Nucleosome exclusion patterns are correlated with various factors that regulate gene expression, which emphasizes the need to include chromatin structural parameters in experimental analysis of gene expression.
Peripheral computing during presentations: perspectives on costs and preferences

Despite the common use of mobile computing devices to communicate and access information, the effects of peripheral computing tasks on people's attention is not well understood. Studies that have identified consequences of multitasking in diverse domains have largely focused on influences on productivity. We have yet to understand perceptions and preferences regarding the use of computing devices for potentially extraneous tasks in settings such as presentations at seminars and colloquia. We explore costs and attitudes about the use of computing devices by people attending presentations. We find that audience members who use devices believe that they are missing content being presented and are concerned about social costs. Other attendees report being less offended by multitasking around them than the device users may realize.
Effects of Proportion and Configuration of Bacillus thuringiensis Cotton on Pest Abundance, Damage, and Yield

Bacillus thuringiensis (Bt) transgenic cotton, Gossypium hirsutum L., kills several economically important pests, reducing injury and increasing yields. Refuges of non-Bt cotton are currently planted with Bt cotton in different designs to slow pest resistance evolution. To compare the effects of differences in Bt/non-Bt plant heterogeneity found in different refuge designs on square (flower bud) damage, abscissions, sap-feeding herbivore densities, and yield in cotton, four types of 24-row cotton plots were planted in 2001 and 2002: 1) seed mixtures of Bt and non-Bt varieties, 2) 12-row strips of Bt and non-Bt, 3) solid Bt, and 4) solid non-Bt. For both years cotton bollworm, Helicoverpa zea (Boddie), damage was less in solid Bt plots than strips and mixtures and all were less than solid non-Bt plots. Cotton fleahopper, Pseudatomoscelis seriatus (Reuter), damage was affected by refuge, but only in 2002 when damage was greater in solid Bt plots than all other plots and greater in strips than solid non-Bt plots. Abscissions were least in solid non-Bt plots, and less in mixtures and strips than solid Bt plots. In 2001, western flower thrips, Frankliniella occidentalis (Pergande), density was greatest in mixtures, whereas sweetpotato whitefly, Bemisia tabaci (Gennadius), was greatest in solid Bt plots, and greater in mixtures than solid non-Bt plots. Yield also was affected by refuge, it was greater for solid Bt plots than for solid non-Bt plots and mixtures in 2001, but the reverse was true in 2002.
Management decisions in aortic regurgitation: has the time for exercise assessment finally arrived?

Aortic regurgitation (AR) is a problem of moderate but increasing frequency. Current data suggest that AR of some degree affects approximately 5% to 10% of the population and increases in frequency and severity with age ([1][1]). When severe, AR gradually leads to irreversible left ventricular (LV)
Distorted spatial warping to compress large, high-resolution rasters for remote-sensing classification

Decisions made early in the data preparation phases of remote-sensing classification projects set fundamental limits on the value to society of the final products. The often-used approach of degrading/down-sampling high-resolution e.g. 1 m pixel size imagery to match lower-resolution data e.g. Landsat 30 m through averaging or majority-rule solves the problem of aligning pixels across bands of differing resolution, but does so by forgoing all ability to detect features smaller than 30 m in addition to potentially discarding up to 99% of the information content of the high-resolution data. The alternative of up-sampling coarser-resolution data into smaller-sized synthetic pixels creates its own set of problems, including potentially enormous file sizes, likely absence of meaningful variation over small spatial scales which may generate matrix singularities fatal to the maximum likelihood classifier, and no assurance of meaningful improvement in classification accuracy despite guaranteed increases in computational time and resource requirements. We propose a new ‘warped space compression technique’ as a variation of vector quantization that analyses local variability in the finest-resolution data available to define acceptable pixel-based neighbourhood N × N sizes over which data can be averaged while minimizing overall information loss. Alternative neighbourhoods are aligned so that nine smaller ones nest within each progressively larger one as 3 × 3 squares, resulting in local data compression options of 3 × 3 ninefold, 9 × 9 81-fold, 27 × 27 729-fold, and 81 × 81 6561-fold. Our transformation process to ‘warped space’ created spatially distorted images with jagged east edges and little visually discernible relationship to the original data. We achieved compressions of 48-to 138-fold in disc storage and 292-to 785-fold in actual numbers of non-null pixels through our choice of cut-off values for accepting 3 × 3, 9 × 9, 27 × 27, or 81 × 81 neighbourhoods of tolerable variability, while otherwise retaining full 1 m resolution data in regions three cells wide by three cells high. Medium-resolution data e.g. Landsat 30 m can be translated into the warped space defined by high-resolution data and composited with it for conducting remote-sensing classifications. When applied to a 71-band, 55-class remote-sensing classification of a 25,500 km2 region centred on the Willamette Valley of Oregon, USA, classification accuracy increased from 64.4% in normal space to 71.3% in warped space. Unsupervised classification in warped space identified several additional categories that could be appended to the 55 existing ground-truth classes, leading to further increases in accuracy. Warped-space compression may be particularly beneficial for ecological studies where it could maintain high resolution in features of interest such as riparian buffers without creating exorbitantly large data files.
Performance studies of Hamamatsu R9800 photomultiplier tube with a new active base designed for use in the Hall D Broadband tagger Hodoscope

This paper presents the results of a study of a high rate photomultiplier and active base assembly designed for use in scintillator counters of the Hall D Jefferson Lab Broadband fixed-array Tagging Hodoscope. In its standard configuration the fixed-array hodoscope consists of 218 plastic scintillator counters made with Hamamatsu R9800 one inch in diameter photomultiplier tube. All tubes are equipped with designed at JLab new active base. The base comprised of a high voltage divider integrated with amplifiers powered by current flowing through the divider (U.S. Patent No. 6,791,269). This original design allows limiting the PMT anode current to 15–20 µA at a 4 MHz count rate, and allows tube operation at lower high voltage bias voltage while retaining a desired overall gain and dynamic range of output signals. The performance of the PMT assemblies were studied at Jeffeson Lab using a picosecond laser (PLP-10). Subsequently, two hundred fifty PMT and base assemblies were manufactured and tested. The results of testing the R9800 photomultiplier in a new active base are presented and discussed.
Village Improvement and the Development of Small Town America, 1853–1893:

Archival research shows that village improvement was not simply a prequel to City Beautiful, but part of a larger rural reform movement responsible for developing small town American in the late nineteenth century. This article presents a detailed historical account of the Laurel Hill Association in Stockbridge, MA, and an overview of the scope of improvement theory and practice at the national level between 1853 and 1893, the period of village improvement’s greatest impact on the development of small town America. This fuller history of village improvement offers important distinctions and emphases that have been previously neglected or not recognized in planning history literature. Further, in light of recent interest in small town America as a precedent for contemporary urban design, this research offers practitioners greater understanding of this archetype’s planning history.
TRANSTHYRETIN CARDIAC AMYLOIDOSIS IS PREVALENT AMONG MEN WITH SEVERE AORTIC STENOSIS UNDERGOING TRANSCATHETER AORTIC VALVE REPLACEMENT

Mounting data demonstrate that transthyretin cardiac amyloidosis (ATTR-CA) is prevalent, underdiagnosed, and an important contributor to heart failure with preserved ejection fraction in older adults with up to 13% of HFpEF subjects affected. Among older adults undergoing transcatheter aortic valve
Hemolysis of sheep erythrocytes sensitized with leptospiral extracts.

SummaryLeptospiral extracts are capable of sensitizing sheep erythrocytes to the HL action of homologous and heterologous leptospiral antiserum and complement, and description of the HL procedure is presented. The HL procedure was shown to be broadly specific, in sharp contrast to the high degree of type specificity seen in the AL procedure. In comparison with HL titrations, the HA reaction was also found to have broad specificity but to be considerably less sensitive than the HL reaction. All 3 procedures were compared in a study involving 580 randomly selected human sera, from which data it would seem that the HL procedure warrants further study as a possible screening tool for the rapid detection and titration of leptospiral antibodies in human sera.
Effect of chlorpromazine on phosphorylation of brain mitochondria.

SummaryChlorpromazine uncoupled the oxidative phosphorylation of brain mitochondria and inhibited cytochrome oxidase in concentrations not affecting overall oxidation. Since the drug inhibits the ATP-ase activity of mitochondria, it presumably does not uncouple by accelerating high energy phosphate breakdown. The suggestion has been made that chlorpromazine acts by reversibly altering intramitochondrial relationships.
Research on the Teacher-student Relationship in Rural Primary Schools of Cangzhou

The study aims at finding the problems in teacher-student relationship so that some suggestions may be provided for rural primary schools.The research method is by questionnaires with two parts: one for teachers, the other for students.Stratified sampling method is used in three rural primary schools in Cangzhou City.It is found that teacher-student relationship in rural primary schools is in general more optimistic,but there is also some disharmony.It is suggested that the society,schools and teachers should give full attention to teacher-student relationship and take effective measures to improve teacher-student relationship in Cangzhou City.
Evaluation of the Benefits of Voice Messaging: The Key to Positioning a New Technology

This manuscript reports the results of a study on the benefits of adopting a voice messaging communications system within the firm. The growing influence of new information based technologies in the workplace is noted. Further, it is noted that the positioning of new technology by marketers is often based on efficiency measures rather than on effectiveness. A pre-use survey regarding the perceptions of voice messaging, as a communication technology, was conducted with 100 managers of a large company. Following the survey, a six month trial of the system was conducted, and a follow-up survey was done to record managers perceptions of benefits after use.
XSat: A Fast Floating-Point Satisfiability Solver

The Satisfiability Modulo Theory (SMT) problem over floating-point arithmetic is a major hurdle in applying SMT techniques to real-world floating-point code. Solving floating-point constraints is challenging in part because floating-point semantics is difficult to specify or abstract. State-of-the-art SMT solvers still often run into difficulties when solving complex, non-linear floating-point constraints.