cssi/SciSciGPT-SciSciNet huggingface dataset:
The stress distribution on the boundary of crazes in polyethylene by the direct and semi-theoretical method

Abstract The stress distribution was determined on the boundary of crazes in a homopolymer and copolymer of polyethylene. The direct method was based on the direct measurement of the strain distribution and the stress-strain curve of the matrix. The semi-theoretical method was that of Wang and Kramer where the displacement profile of the craze was measured and the stress was calculated by a linear theory of elasticity. The assumption of linear elasticity in the matrix produces higher values of the stress when compared to the results of the direct method and the shape of the stress distribution is somewhat different.
Powering a wireless sensor node with a vibration-driven piezoelectric energy harvester

This paper discusses the direct application of scavenged energy to power a wireless sensor platform. A trapezoidal piezoelectric harvester was designed for a specific machine tool application and tested for robustness and longevity as well as performance. The design focused on resonant performance and distributed strain concentrations at a given resonant frequency and acceleration. Critical issues of power coupling and conditioning between harvester and wireless platform were addressed. The wireless platform consisted of a sensor, controller, power conditioning circuitry, and a custom low power radio. The system transmitted a sensor sample once every 10 s in a scavenging environment of 0.25 g and 100 Hz for a system duty cycle of approximately 0.2%.
Symmetric Functions and Generating Functions for Descents and Major Indices in Compositions

In [18], Mendes and Remmel showed how Gessel’s generating function for the distributions of the number of descents, the major index, and the number of inversions of permutations in the symmetric group could be derived by applying a ring homomorphism defined on the ring of symmetric functions to a simple symmetric function identity. We show how similar methods may be used to prove analogues of that generating function for compositions.
Diversification and market performance

Recent theoretical research indicates that diversification may affect industry profitability for reasons (e.g., improved efficiency and increased entry) other than the exercise of marketpower by conglomerate firms. This paper examines empirically the relationship between diversification (as an element of market structure) and industry profitability using three relatively new measures of diversification. The evidence reported reveals a statistically significant relationship which is consistent with the efficiency and entry hypotheses.
Nonparametric recovery of interblock information in clinical trials with a surrogate endpoint

For clinical trials involving (a treatment-wise) incomplete block design and a surrogate variable as a substitute for the primary endpoint, recovery of interblock information in nonparametric analysis of covariance models based on a suitable aligned rank statistics is explored through a combined inference scheme based on intra as well as interblock rank statistics incorporating both the surrogate replicates and the validation samples. Related nonparametrics are presented in detail.
Perinatal outcome in women with recurrent preeclampsia compared with women who develop preeclampsia as nulliparas

OBJECTIVE: To compare the rates and perinatal outcome in women who experienced preeclampsia in a previous pregnancy to those in women who developed preeclampsia as nulliparas. STUDY DESIGN: This is a secondary analysis of data from 2 separate multi-center trials of aspirin for prevention of preeclampsia. Women who had preeclampsia in a previous pregnancy (n = 598) were compared with nulliparous women (n = 2934). Outcome variables were rates of preeclampsia, preterm delivery at <37 and <35 weeks of gestation, small-for-gestational-age infant, abruptio placentae, and perinatal death. Data were compared by using chi-square analysis and Wilcoxon rank sum test. RESULTS: The rates of preeclampsia and of severe preeclampsia were significantly higher in the previous preeclamptic group as compared to the nulliparous group (17.9% vs 5.3%, P <.0001, and 7.5% vs. 2.4%,P <.0001, respectively). Women who had recurrent preeclampsia experienced more preterm deliveries before 37 and 35 weeks of gestation than nulliparous women who developed preeclampsia. In addition, among women who developed severe preeclampsia, those with recurrent preeclampsia had higher rates of preterm delivery both before 37 weeks (67% vs 33%, P =.0004) and before 35 weeks of gestation (36% vs 19%,P =.041), and higher rates of abruptio placentae (6.7% vs 1.5%) and fetal death (6.7% vs 1.4%) than did nulliparous women. CONCLUSION: Compared to nulliparous women, women with preeclampsia in a previous pregnancy had significantly higher rates of preeclampsia and adverse perinatal outcomes associated with preterm delivery as a result of preeclampsia. (Am J Obstet Gynecol 2002;186:422-6.)
Pakistan's Battlefield Nuclear Policy: A Risky Solution to an Exaggerated Threat

Pakistan has introduced a new battlefield nuclear weapon, Nasr, into its arsenal. Nasr, a short-range ballistic missile, was first flight-tested in 2011. Pakistani leaders have declared that the weapon is meant to deter India from executing its Cold Start war doctrine. The doctrine was conceived by members of India's army and its strategic community in 2004 as a solution to perceived operational shortcomings of the army in responding to major terrorist incidents involving Pakistanis. It recommends the positioning of smaller army units at the international border with the capability to rapidly invade Pakistan and occupy narrow slices of territory, while denying Pakistan the ability to anticipate the attack and to immediately assemble a counterattack force. The Cold Start war doctrine, however, has since been publicly disavowed by the Indian government, and the Indian army has not reorganized or equipped its troops in a manner consistent with the doctrine. Further, the use of battlefield nuclear weapons ins...
Issues in ad hoc networks: scaling laws, media access control, and power control

We present a brief account of three problems in wireless networks. First we address the issue of scalability. We show that, in theory, under a certain model of interference, a network with n nodes in a domain can provide at best a per-node throughput of O (1/√n) bits/sec to random destinations, which further drops to O (1/√n log n) if the nodes are randomly located. Then we present the results of an experimental investigation with IEEE 802.11 technology: The per node throughput follows a O (1/n 1.68 ) scaling law which is considerably worse than what theory suggests is attainable. These results appear to suggest the need for an improved media access control protocol. So motivated, we present a new media access control protocol for ad hoc networks, called SEEDEX. It attempts to make reservations without explicitly doing so for each and every packet. The idea is for each node to use a random schedule. Nodes can inform each other about their schedules merely by exchanging the seeds of their pseudo random number generators. We present the design, as well as some simulation results comparing it with IEEE 802.11. Last we turn to the problem of power control in ad hoc networks. We present a new protocol called COMPOW, which is designed to find the lowest power level at which the entire network is connected. We provide the theoretical justification for it, and a solution of the architectural issues involved. Using a notion of parallel modularity at the network layer, this protocol provides a joint solution for both the routing and power control problems, which can be used in plug and play manner with any routing protocol which employs a routing table. It has been implemented in the Linux kernel. For full details of these abbreviated results, we refer the reader to.
Labor market institutions, international capital mobility, and the persistence of underdevelopment

Abstract We show that the impact of globalization on growth and wages crucially depends on the labor market structures of the countries involved. We contrast bargaining and perfect competition. Under perfect capital markets, convergence of capital and income per capita always occurs despite different labor market structures. However, different labor market structures prevent convergence of the income shares, with unionized countries showing a lower wage rate and consequent capital inflows. Therefore unionization, not globalization, is the cause of discrepancies in the within-country income-distribution patterns. Openness is always preferable to autarky for a small developing economy, independently of its labor market structure.
Identifying, characterizing, and controlling stealth worms in wireless networks through biological epidemiology

This paper defines and evaluates a network security system, Rx, inspired by biological epidemiology that defends wireless networks against stealth worms. Rx applies concepts from epidemiology to identify and control worm behavior at the network level by aggregating and processing end-host anomaly reports. The system uses bio-mathematical modeling and demographic analysis to identify, characterize, forecast, and control network stealth worms early in the infection cycle. We present the design of Rx with simulation results that show the system increases by nearly an order of magnitude the survival rate of portable wireless devices under attack by a network stealth worm.
The role of test trials in paired-associate learning

This study investigated the effect of varying the events occurring between two reinforced trials on the course of learning. It was found that the effectiveness of a second reinforced trial was greater; (a) for the longer of two inter-reinforcement intervals prior to the second reinforced trial; (b) if S is not specifically tested for retention of the reinforced item; (c) for filler trials that made no specific demands on S.
A kinetic study of the bisulphite reduction of methionine sulphoxide to methionine.

The rates of reduction of methionine sulphoxide to methionine by aqueous bisulphite solutions were measured by n.m.r. spectroscopy. The reaction was shown to follow overall second-order kinetics, being first-order with respect to methionine sulphoxide and first-order with respect to bisulphite anion. The reduction was shown to have a strong pH dependence, reaching a maximum rate at pH 2.9. The pH-rate profile has been related to the concentrations of bisulphite anion and protonated methionine sulphoxide and to the ionic state of methionine sulphoxide. A mechanism consistent with these results is proposed. An energy of activation of 14.1 kcal/mole was obtained for the reaction. These reductions are proposed to have important nutritional implications.
Dimensional scaling and the quantum mechanical many-body problem

A growing repertoire of electronic structure methods employ the spatial dimensionD as an interpolation or scaling parameter. It is advantageous to transform the Schrodinger equation to remove all dependence onD from the Jacobian volume element and the Laplacian operator; this introduces a centrifugal term, quadratic inD, that augments the effective potential. Here we explicitly formulate this procedure forS states of an arbitrary many-particle system, in two variants. One version reduces the Laplacian to a quasicartesian form, and is particularly suited to evaluating the exactly solvableD → ∞ limit and perturbation expansions about this limit. The other version casts the Jacobian and Laplacian into the familiar forms forD=3, and is particularly suited to calculations employing conventional Rayleigh-Ritz variational methods.
Suppression of hepatic CYP3A1/2 and CYP2C11 by cyclosporine is not mediated by altering growth hormone levels.

Cyclosporine (CsA) suppresses drug metabolism by decreasing cytochrome P450 (P450) enzyme levels in rat liver. Growth hormone (GH) is known to pretranslationally regulate P450 expression. Thus, the suppression of P450 by CsA may involve GH as an intermediate. To address this question, we examined the effects of administering exogenous GH via twice daily subcutaneous injections and in conjunction with chronic subcutaneous CsA administration for 14 days on hepatic P450 expression. CsA alone decreased CYP3A1/2 and CYP2C11 significantly, in a manner similar to that previously found. When administered in the absence of CsA, GH also suppressed CYP3A1/2 and CYP2C11 protein levels as compared with GH vehicle. In the presence of CsA, GH did not cause further suppression of either CYP3A1/2 or CYP2C11 expression when compared with CsA treatment with GH vehicle. Testosterone in vitro catalytic assays confirmed that CsA and GH separately cause significant decreases in activity levels. Also, the concomitant administration of GH and CsA caused lowered production of 16α-, 2α-, 6β-, and 2β-hydroxytestosterone as compared with the administration of GH with CsA vehicle and as compared with the administration of GH vehicle with CsA. This study shows that GH is a dominating factor over CsA in determining hepatic P450 expression and activity. In addition, CsA does not seem to alter GH levels as a mediating event in suppressing P450 expression and activity. Since CsA given in combination with GH further suppressed P450 activity as compared with CsA given in combination with vehicle, this suggests that changes in hormonal status are likely to be one of the many factors that is responsible for the lack of a clear association between cyclosporine dosing and markers of toxicity.
Band Systems of MgCl, CaCl and SrCl

A vibrational analysis has been made of band systems due to MgCl, CaCl and SrCl. There are two systems due to MgCl with ${{\ensuremath{\nu}}_{\mathrm{E}}}^{*}=26,441.5$, ${\ensuremath{\omega}}^{\ensuremath{'}}=474.8$ and ${\ensuremath{\omega}}^{\ensuremath{'}\ensuremath{'}}=447.4$ for the more intense system and ${\ensuremath{\nu}}_{\mathrm{E}}=25,887.2$, ${\ensuremath{\omega}}^{\ensuremath{'}}=466.9$ and ${\ensuremath{\omega}}^{\ensuremath{'}\ensuremath{'}}=447.4$ for the less intense system. CaCl has three extensive systems with ${\ensuremath{\nu}}_{\mathrm{E}}=16,093.5$, ${\ensuremath{\omega}}^{\ensuremath{'}}=367.1$, ${\ensuremath{\omega}}^{\ensuremath{'}\ensuremath{'}}=364.5$; ${\ensuremath{\nu}}_{\mathrm{E}}=16,850.6$, ${\ensuremath{\omega}}^{\ensuremath{'}}=361.0$, ${\ensuremath{\omega}}^{\ensuremath{'}\ensuremath{'}}=364.0$; ${\ensuremath{\nu}}_{\mathrm{E}}=26,498.9$, ${\ensuremath{\omega}}^{\ensuremath{'}}=336.0$, ${\ensuremath{\omega}}^{\ensuremath{'}\ensuremath{'}}=368.3$, respectively. There are also three weakly developed systems. Two strong systems of SrCl are observed with the respective constants ${\ensuremath{\nu}}_{\mathrm{E}}=15,716.9$, ${\ensuremath{\omega}}^{\ensuremath{'}}=306.3$, ${\ensuremath{\omega}}^{\ensuremath{'}\ensuremath{'}}=301.6$ and ${\ensuremath{\nu}}_{\mathrm{E}}=25,245.5$, ${\ensuremath{\omega}}^{\ensuremath{'}}=280.4$, ${\ensuremath{\omega}}^{\ensuremath{'}\ensuremath{'}}=300.6$. SrCl has three poorly defined systems as well. The isotope effect due to ${\mathrm{Cl}}^{35}$ and ${\mathrm{Cl}}^{37}$ is observed in all transitions.The rotational structure is partially resolved for most systems, and in the ultraviolet CaCl bands sufficiently to estimate that ${B}^{\ensuremath{'}}=0.24$ and ${B}^{\ensuremath{'}\ensuremath{'}}=0.26$. The electronic states and dissociation products are discussed. All values are expressed in ${\mathrm{cm}}^{\ensuremath{-}1}$.
Unsupervised multiscale classification using wavelet-domain hidden Markov tree model

A new texture image segmentation algorithm, HMTseg, was recently proposed and applied successfully to supervised segmentation. In this paper, we extend the HMTseg algorithm to unsupervised multiscale segmentation. A Gaussian mixture density is applied to approximate each wavelet coefficient's joint statistics through modeling each scale and each subband's histogram. A multiscale Expectation Maximization (EM) algorithm is used to integrate the parameter estimation and classification into one. Then, by the Hybrid Contextual Labeling Tree (HCL T), a Bayesian interscale and intrascale fusion algorithm is applied to raw segmentation results to obtain accurate and reliable final segmentations.
Phospholipase A2 engineering. Deletion of the C-terminus segment changes substrate specificity and uncouples calcium and substrate binding at the zwitterionic interface.

It has been suggested [Dijkstra, B. W., Drenth, J., & Kalk, K. H. (1981) Nature 289, 604-606] that the interfacial binding site of phospholipase A2 (PLA2) involves a large number of residues, including a cluster at the N-terminus and another cluster at the C-terminus. The approaches of multiple mutation and deletion were used to test the roles of the C-terminal residues of bovine pancreatic PLA2 overexpressed in Escherichia coli. A double mutant K120A/K121A and a deletion mutant delta 115-123/ C27A were constructed, and structural and functional analyses were performed on both mutants. The double mutant showed little perturbation in the global structure on the basis of proton NMR and X-ray crystallographic analyses. The proton NMR analysis of the deletion mutant suggested that a few residues at the active site, the hydrophobic channel, and the calcium binding loop are perturbed, but the global conformation is not changed. The mutants were then characterized for catalytic and binding properties by use of various kinetic and spectroscopic methods. The double mutant behaved in a manner similar to that of the wild type (WT) PLA2 in every property examined. The deletion mutant was found to show an interesting change of substrate specificity. The kcat,app of the zwitterionic DC8PC micelles but not the anionic DC8PM micelles decreased by a factor of > 100; however, the activity of DC8PC was restored upon addition of 4 M NaCl. The results of fluorescence spectroscopic studies indicate that the deletion mutant behaves in a manner similar to that of WT in the binding to anionic vesicles and to zwitterionic neutral diluent. Thus, the binding affinity of the enzyme to the interface (the E to E* step) should not be the main cause for the change in substrate specificity. The cause lies at least partially in the binding of substrate or inhibitor to the active site of the enzyme at the interface, i.e., the E* to E*L step, as revealed by the results of equilibrium binding studies. The equilibrium dissociation constants of ligands are generally higher for the deletion mutant (relative to WT) at the zwitterionic interface but not at the anionic interface. The cause for the low affinity of an active site-directed ligand to the active site at the zwitterionic interface could be related to the inability of Ca2+ to enhance ligand binding for the deletion mutant. This is in contrast to the WT PLA2 for which Ca2+ binding enhances binding of the substrate to the active site. Overall, the structural and functional perturbations caused by deleting the C-terminal segment are modest, but the changes in substrate specificity and the uncoupling between substrate and calcium binding are interesting and significant.
The Mood of a Worm

The human nervous system is a vastly complex network of functionally interconnected cells whose detailed structure is at present beyond reach. All our actions, calculations, feelings, memories, dreams—consciousness itself—emerge from its workings. To understand this colossal, enigmatic structure, experimentally amenable model animals with tractable nervous systems many orders of magnitude smaller are studied. A popular choice has been the worm Caenorhabditis elegans , a nematode 1 mm long with a nervous system containing fewer than 400 neurons. On pages 540 and 543 in this issue, Garrison et al. ( 1 ) and Beets et al. ( 2 ), respectively, add to a growing body of evidence that even at the highest levels of coordinating fundamental and complex behaviors, the same neural mechanisms are at work in worms and humans.
Inelastic collisions of three particles on a line as a two-dimensional billiard

Abstract We study the inelastic collisions of three particles on a line. We show that this system is a two dimensional billiard in a semi-enclosed space with unconventional reflection laws. Using this geometric language, we describe completely the dynamics of this system. We find that the asymptotic behavior changes when the coefficient of restitution becomes smaller than a critical value r c . For r > r c , the system can be understood in terms of a conventional billiard in an infinite wedge. For r ≤ r c , this is no longer true and the asymptotic behavior is richer. We also investigate the question of triple collisions and find that they are regularizable only for certain values of r .
Chemokine receptors as fusion cofactors for human immunodeficiency virus type 1 (HIV-1)

CD4 is the primary cellular receptor for human immunodeficiency virus type 1 (HIV-1), but is not sufficient for entry of HIV-1 into cells. After a decade-long search, the cellular coreceptors that HIV-1 requires in conjunction with CD4 have been identified as members of the chemokine receptor family of seven-transmembrane G-protein coupled receptors. The discovery of distinct chemokine receptors that support entry of T-cell tropic (CXCR-4) and macrophage tropic HIV-1 strains (CCR-5) explains the differences in cell tropism between viral strains, the inability of HIV-1 to infect most nonprimate cells, and the resistance of a small percentage of the population to HIV-1 infection. Further understanding of the role of chemokine receptors in viral entry may also help explain the evolution of more pathogenic forms of the virus, viral transmission, and HIV-induced pathogenesis. These recent discoveries will aid the development of strategies for combating HIV-1 transmission and spread, the understanding of HIV-1 fusion mechanisms, and the possible development of small animal models for HIV-1 drug and vaccine testing.
Structural evidence for an anion-directing track in the hen ovotransferrin N-lobe: implications for transferrin synergistic anion binding.

The transferrins are a class of iron-binding proteins that require the presence of a synergistic anion for conformation-dependent binding of ferric ions. Bromopyruvate, a known synergistic anion and affinity label of ovotransferrin (oTF) [Bailey, C. T., Patch, M. G., & Carrano, C. J. (1988) Biochemistry 27, 6276−6282], was used to probe the structure of the metal- and anion-binding sites of the functional N- and C-terminal proteolytic halves (oTF/2N and oTF/2C, respectively) of ovotransferrin. Incubation of oTF/2N with [2-14C]bromopyruvate in the presence of Fe3+ ions resulted in the incorporation of 0.70 mol of 14C label/mol of oTF/2N; 14C-labeled oTF/2N was then purified and digested sequentially with trypsin and V8 protease to determine the sites of modification. Quantification of 14C radioactivity, analysis of purified 14C-labeled peptides by gas-phase sequencing and mass spectrometry demonstrated that chemical modification was restricted to nucleophilic residues contained in a fragment corresponding ...
Breaking the Code of Polyadenylation-Induced Translation

The translation of many maternal mRNAs is regulated by dynamic changes in poly(A) tail length. During maturation of Xenopus oocytes, polyadenylation is mediated by three different cis elements in the 3′ untranslated region (UTR) of maternal mRNAs. In this issue, Pique et al. (2008) explore the interplay of these elements to elucidate a combinatorial code that predicts the timing of polyadenylation and translation of maternal mRNAs.
Building New Networks from the Old: Women's Experiences with Electronic Communications

Abstract Although computer networking holds the potential for empowering, egalitarian experiences for participants, the experiences of women using e-mail point, as well, to ways that the technology supports and replicates structures of dominance and oppression. As scholarship in composition has not accounted for the sexual commodification and harassment of women using e-mail, this article turns to research done in human-factors research, business, and sociology in order to contextualize the discussion of the ways computer-mediated communications changes the environment in which they are placed. This research supports the argument that patterns of interaction deeply entrenched within a patriarchal system cannot be undermined simply by offering access to a new medium. In moving away from traditional discourse forms that oppress and marginalize women without analyzing the ideologies that inform their formation and staying power, we run the risk of those ideologies becoming dominant once again in another forum.
Regional accumulation of vegetal pole poly(A) + RNA injected into fertilized Xenopus eggs

Cytoplasmic determinants localized in particular regions of the egg seem to be important in cell determination during early embryogenesis1,2. Although their composition is uncertain, there is evidence that some are partly composed of maternal RNA molecules3–6. Consistent with this possibility, maternal poly(A)+ RNA and certain specific RNA sequences are reported to show an uneven distribution in the cytoplasm of oocytes and developing embryos7–11, suggesting that maternal RNA sequences may contain signals required to distribute themselves in specific cytoplasmic regions of the egg. We have now tested this idea by analysing the distribution of RNA sequences localized in the vegetal pole cytoplasm of Xenopus laevis eggs after microinjection into fertilized zygotes. We report that exogenous vegetal pole poly(A)+ RNA accumulates along a concentration gradient from the vegetal hemisphere to the animal hemisphere of the injected egg and provide evidence that the concentration gradient is set up by active migration of the injected vegetal pole poly(A)+ RNA into the vegetal hemisphere cytoplasm between fertilization and the first cleavage.
Unified model for drift velocities of electrons and holes in semiconductors as a function of temperature and electric field

Abstract An improved analytical formula for the drift velocities of hot electrons and holes in semiconductors is suggested. Calculated results from the model show striking agreements with the available experiments. Unlike the earlier ones, the model predicts the low-field peak velocity characteristics very well, and appears to exhibit wide applicability. It is claimed to be one of the most general models available in the literature, for which attempts are made to provide a theoretical basis.
Conference report: Conference on experiences in applying parallel processors to scientific computation

There is general agreement that uniprocessor speeds are nearing fundamental limits and that the only way that more speed can be attained is to exploit computational parallelism of one sort or another. The concept is simple but the implementations are not. Clearly, the way to the future must be evolutionary, and it will require the skills of the computer industry, universities, and the national laboratories. The first production mutiprocessor supercomputer systems are now being delivered. Indications are that within the next five years supercomputer manufacturers will offer systems with up to 16 processors. Successful exploitation of their potential performance will require algorithms, software, and hardware that, when combined as a single system, will achieve high-average processor utilization and introduce little additional work relative to a single-processor implementation. The questions of how best to do these things are occupying the attention of researchers all over the world. This work is considered the key to expansion of computer performance. Within the past two years, a significant amount of experimentation on the parallel processing of scientific computation has been done. Most of this work as related to Supercomputers has not been previously reported. Consequently, on March 13-15, Lawrence Livermore National Laboratory and Los Alamos National Laboratory hosted a meeting at Gleneden Beach, Oregon, at which many of these experiments were discussed. The general thrust of these presentations suggests several important results such as 1. A broad spectrum of scientific computation is amenable to parallel processing. The presentations revealed that parallel formulations have been achieved for meaningful computational kernels from such areas as Plasma simulation, Lagrangian fluid flow simulation, Reactor safety simulation, Automated reasoning,
Heterogeneity of resting and hyperemic myocardial blood flow in healthy volunteers: a quantitative CMR perfusion pixel-map study

Methods Quantitative CMR perfusion was performed at 1.5T in 17 healthy volunteers under baseline (rest) and adenosine hyperemia (stress). Median filters with different kernel size were used to estimate MBF at different resolutions (0.07 g, 0.27 g, 0.61 g, 1.1 g of myocardium). MBF heterogeneity was evaluated as the relative dispersion ([RD] = standard deviation/mean) on basal- and mid-ventricular slices for each subject. Paired t-tests and linear mixed-models were used to account for withinsubject effects. Results All normal volunteers had Framingham scores <1%. MBF at rest was 1.1 ml/g/min (95% CI: 0.9 to 1.2 ml/g/ min) vs. adenosine stress 2.8 ml/g/min (95% CI: 2.4 to 3.1 ml/g/min [p < 0.001]). At the intrinsic image acquisition resolution (1 voxel = 0.07 g), the RD was 13.0% (95% CI: 11.7 to 14.3%) at rest vs. 15.9% (95% CI: 14.1 to 17.7%) at adenosine stress (p = 0.004). For increasing voxel sizes, the RD of MBF under rest and stress conditions decreased in a highly-significant pattern (Figure 1). There were no detectable differences in pairwise comparisons of RD between basal and mid-slices at rest or under hyperemic conditions (all p = NS).
The effects of CER training on the acquisition of a successive operant discrimination

Following key peck training to a chromatic stimulus, one group of pigeons was given CER training with a white vertical line superimposed on the key as the CS and shock as the US; a second group was given presentations of the CS only; a third group received shock only with no CS preceding it on the key; a fourth group received only the key peck training with the chromatic stimulus. All groups then received identical training on a successive operant discrimination involving auditory stimuli. The CER subjects learned this discrimination faster than did subjects in the other three groups, which did not differ. The results extend the generality of conditions which facilitate the acquisition of successive operant discriminations.
Age-related decline in thirst and sodium appetite in rats related to kininase II inhibition.

Abstract Water intake was examined in young (3–5 months) and old (20–24 months) rats following peripheral administration of either angiotensin (Ang) II or captopril + bradykinin (BK). Relative to body weight, intake after Ang II showed no age-related difference, while that after captopril + BK was markedly reduced in the old rats. In other rats that were not allowed to drink after captopril + BK, the induction of Fos-like immunoreactivity (IR) was much lower in the subfornical organ, supraoptic and median preoptic nuclei of old rats compared with their young counterparts. Intake of 0.15 M NaCl during chronic dietary administration of enalapril was robust in young rats but was much reduced in old rats, as was their plasma renin activity. Thus, reduced thirst and sodium appetite are found in conjunction with kininase II (angiotensin-converting enzyme) inhibitors in aging rats, possibly because they fail to generate the high levels of circulating renin seen in young rats under these conditions.
Adjuvant radiotherapy and survival outcomes in early-stage endometrial cancer: A multi-institutional analysis of 608 women

Abstract Objective. The role of post-operative radiotherapy (RT) in women with early-stage, low to intermediate risk cancer of the uterine corpus remains controversial. The primary objective of this analysis was to evaluate the survival outcomes of women with early-stage endometrial cancer treated with surgery alone or surgery followed by RT. Methods. Data from two institutions were collected from 1990 to 2003. The 608 eligible women had FIGO stage IA to IIA endometrial cancer and underwent primary surgery±RT. Univariate and multivariate analyses of pertinent variables were performed for the end points of disease-free survival (DFS) and overall survival (OS). Results. The median age for all women was 64 years. RT was delivered to 133 women (22%). Unfavorable histologic grade ( P P Conclusions. Adjuvant RT was associated with improved disease-free and overall survival in women with higher risk disease. Despite significantly worse disease characteristics among women in the adjuvant RT group, the analyzed end points were equivalent among the two groups. These findings suggest that adjuvant radiotherapy has a significant benefit in reducing mortality and disease progression in early-stage carcinoma of the uterine corpus.
Efficient nondestructive equality checking for trees and graphs

The Revised6 Report on Scheme requires its generic equivalence predicate, equal?, to terminate even on cyclic inputs. While the terminating equal? can be implemented via a DFA-equivalence or union-find algorithm, these algorithms usually require an additional pointer to be stored in each object, are not suitable for multithreaded code due to their destructive nature, and may be unacceptably slow for the small acyclic values that are the most likely inputs to the predicate.This paper presents a variant of the union-find algorithm for equal? that addresses these issues. It performs well on large and small, cyclic and acyclic inputs by interleaving a low-overhead algorithm that terminates only for acyclic inputs with a more general algorithm that handles cyclic inputs. The algorithm terminates for all inputs while never being more than a small factor slower than whichever of the acyclic or union-find algorithms would have been faster. Several intermediate algorithms are also presented, each of which might be suitable for use in a particular application, though only the final algorithm is suitable for use in a library procedure, like equal?, that must work acceptably well for all inputs.
Analysis of sex-mismatched human corneal transplants by fluorescence in situ hybridization of the sex-chromosomes.

The fate of the cells of corneal transplants has been controversial from the early days of keratoplasty. Various methods such as histological evaluation, radiolabeling of donor cells or Barr-body analysis have been applied to clarify the issue. However, the question whether the transplanted cells are replaced or survive, remains unsolved. In this study, we applied fluorescence in situ hybridization (FISH) of the X- and Y-chromosomes in paraffin sections of explanted sex-mismatched corneal transplants to distinguish between host and donor cells. Fourteen sex-mismatched cases with various reasons for explantation and different postoperative time intervals ranging from 11 months to 30 years were analysed. We found that all cell types, including epithelium, keratocytes and endothelial donor cells were replaced in most cases as early as 1 year after transplantation. In three cases, however, up to 26% of donor keratocytes were still detected up to 4.5 years after transplantation, demonstrating a certain individual variability in the process of replacement. Further studies must show if the extent and timing of donor cell replacement in clinically successful, totally clear transplants is different. Our results are in keeping with the phenomenon of recurrences of corneal dystrophies in the graft, the significant postoperative decline of the endothelial cell density, the fact that typical graft rejections usually take place within 1-2 years postoperatively and that relatively late rejections can occur in rare cases probably due to some surviving stromal keratocytes. Donor cell replacement is a special feature of corneal transplants when compared with other kinds of organ transplants and might be due to the presence of the same tissue type in the immediate neighbourhood of the graft.
Investigation of a grating-based stretcher/compressor for carrier-envelope phase stabilized fs pulses

In this work, we experimentally investigate the effect of a grating based pulse stretcher/compressor on the carrier-envelope phase stability of femtosecond pulses. Grating based stretcher-compressor (SC) setups have been avoided in past demonstrations of chirped pulse amplification (CPA) of carrier envelope phase (CEP) stabilized femtosecond pulses, because they were expected to introduce significantly stronger CEP fluctuations than material-based SC systems. Using a microstructure fiber-based detection setup, we measure CEP fluctuations of ΔΦCE,SC=340 milliradians rms for a frequency range from 63 mHz to 102 kHz for pulses propagating through the SC setup. When bypassing the beam path through the SC, we find CEP fluctuations of ΔΦCE,bypass=250 milliradians rms. These values contain significant contributions from amplitude-to-phase conversion in our microstructure fiber-based detection setup for ΔΦCE. Hence, we do not unambiguously measure any added CEP noise intrinsic to the SC setup. To distinguish between intrinsic SC effects and amplitude-to-phase conversion, we introduce controlled beam pointing fluctuations Δα and again compare the phase noise introduced when passing through/bypassing the SC. Our measurements do not reveal any intrinsic effects of the SC system, but allow us to place an upper limit on the sensitivity of our SC system of ΔΦCEintrinsic,SC/Δα<13000 rad/rad. Our results demonstrate experimentally that there is not a strong coupling mechanism between CEP and beam pointing through a stretcher/compressor, as well as measuring significantly smaller CEP fluctuations than experimental results reported previously.
The Role of Risks in Mammalian Combat: Zebra and Onager Fights

Risks associated with the loss of balance were important factors constraining offensive tactics during the fights of two species of large mammalian herbivores, zebras (Equus bitrchelli) and onagers (E. hemionus). Evenly matched adversaries faced greater risks than disparately matched ones. Risks were assumed often, but whether or not they were capitalized on depended upon an opponent's fighting ability. Behavior patterns such as rearing increased the probability of scoring successful bites, but they also carried the greatest risks. Retaliations were more likely when such patterns were used. Zusammenfassung Die heutigen Pferdeartigen haben keine spezialisierten Kampf-Waffen; sie benutzten im Kampf als wichtigste Waffen die Zahne, dazu die Beine zum Schlagen. Verschiedene Taktiken werden eingesetzt, um erfolgreiche Bisse zu plazieren. Dazu gehort, den Rivalen aus dem Gleichgewicht zu bringen sowie dauernd und schnell zuzubeisen. Der Sieg beruht auf einer Kombination effektiver Angriffs- und Verteidigungsaktionen. Wie bei anderen Saugern ist Kampfverhalten risikobeladen. Verhalten, das leicht zu Wunden fuhrt, ist auch riskanter. Bei genngen Verschiedenheiten zwischen den Kampfern nimmt das Kampfrisiko zu, besonders in eskalieren-den Kampfen. Ab einer bestimmten Grenze uberwiegen die Risiken, nicht mehr mogliche Vorteile; das Verhalten des Individuums verlast den Bereich einer optimalen Taktik.
Perceptual biases for multimodal cues in chimpanzee (Pan troglodytes) affect recognition.

The ability of organisms to discriminate social signals, such as affective displays, using different sensory modalities is important for social communication. However, a major problem for understanding the evolution and integration of multimodal signals is determining how humans and animals attend to different sensory modalities, and these different modalities contribute to the perception and categorization of social signals. Using a matching-to-sample procedure, chimpanzees discriminated videos of conspecifics’ facial expressions that contained only auditory or only visual cues by selecting one of two facial expression photographs that matched the expression category represented by the sample. Other videos were edited to contain incongruent sensory cues, i.e., visual features of one expression but auditory features of another. In these cases, subjects were free to select the expression that matched either the auditory or visual modality, whichever was more salient for that expression type. Results showed that chimpanzees were able to discriminate facial expressions using only auditory or visual cues, and when these modalities were mixed. However, in these latter trials, depending on the expression category, clear preferences for either the visual or auditory modality emerged. Pant-hoots and play faces were discriminated preferentially using the auditory modality, while screams were discriminated preferentially using the visual modality. Therefore, depending on the type of expressive display, the auditory and visual modalities were differentially salient in ways that appear consistent with the ethological importance of that display’s social function.
Evidence that phosphoinositide response is mediated by α1-adrenoceptor stimulation, but not linked with excitation-contraction coupling in cardiac muscle

Phosphoinositide metabolism is known to be associated with neuronal or humoral stimulation of excitable cells. The present study examined whether the phosphoinositide response is involved in such events using isolated rat papillary muscles labeled with [3H]inositol. It was found that neither increase in the stimulation frequencies (0-2 Hz) nor prolongation of the pulse duration (10-70 msec) altered the labeling of phosphoinositides and the accumulation of [3H]inositol phosphates in this preparation. However, phenylephrine, a known alpha 1-agonist, was capable of provoking the breakdown of phosphoinositides associated with a positive inotropic effect in this preparation. We report the evidence that phosphoinositide response is mediated by alpha 1-adrenoceptor stimulation, but not linked with excitation-contraction coupling in cardiac muscle.
A goodness of fit algorithm for empirical data

This paper describes a computer program that fits empirical data to any of 10 theoretical distributions. Tests include the Chi-square, Kolmogorov-Smirnov and Moments Test. Of particular interest is an interface language which has been appended in order to ease the burden of input. This program has been used successfully in stochastic simulation and modeling courses for the past four years at the University of Southern Mississippi.
Multiple attenuation in crustal-scale imaging: examples from the TAIGER marine reflection data set

During summer of 2009, multi-channel marine seismic reflection data and wide-angle refraction data were acquired as part of the joint NSF and Taiwanese-funded TAIGER program with the goal of understanding the dynamics of arc-continent collision in Taiwan. One of the principle difficulties of crustal-scale imaging with marine reflection data such as these is the prevalent multiple contamination that obscures many of the deep crustal targets. Without effective treatment of multiples, many of the objectives of the TAIGER active source program may not be achieved. We present three profiles, one from each acquisition leg, that demonstrate the effectiveness of 2D surface-related multiple elimination (SRME) and radon filtering in attenuating much of this unwanted energy in broad ranges of water depths, seafloor topographies and lithologies. Two profiles from south of Taiwan image 3–4 km of sedimentary strata overlying moderately extended continental crust along the Eurasia continental shelf and a 5–6 km thick sedimentary section overlying thin crust consisting of faulted blocks and volcanic bodies along the continental slope. Our multiple attenuation efforts also reveal a seaward-dipping normal fault that penetrates into the upper mantle and separates thick crust of the continental shelf from thin crust of the continental slope. A profile from east of Taiwan reveals thin ocean crust of the Philippine Sea plate subducting beneath the Ryukyu trench that may be traced beneath the accretionary prism and Ryukyu forearc. These profiles demonstrate the success of our imaging strategy in the range of imaging environments spanned by the TAIGER marine reflection seismic data.
Changes in circadian sleep and waking patterns after somatosensory deafferentation in the cat.

Abstract The present study describes changes in circadian state pattern organization associated with somatosensory deafferentation in the adult cat. Nine animals, implanted for chronic monitoring of standard sleep state variables, were divided into 3 groups for study. Six cats received dorsal column transections at either a high (C1–C3, N = 3) or low (C5–T1, N = 3) cervical level. The remaining three served as intact controls. State evaluations of continuous 24 h polygraphic recordings disclosed a significant facilitation of alert waking and a suppression of slow wave sleep in animals with high cervical lesions; REM sleep was not affected. State pattern percentages for animals with low cervical lesions were comparable to those of intact controls; however, lesioned animals of both experimental groups showed changes in the frequency of occurrence and duration of individual sleep/wake episodes. These findings were interpreted in terms of the enhancement of intrinsic rhythmic discharge patterns over ventrobasal thalamocortical pathways.
Biochemical recurrence rate in patients with positive surgical margins at radical prostatectomy with further negative resected tissue

OBJECTIVE To determine the biochemical recurrence (BCR) rate in patients with positive surgical margins (PSMs) on the prostate specimen who have additional negative tissue resected from that site (M+ −), compared to patients with negative margins (M−) and those with persistent PSM (M+), as those with PSM at radical prostatectomy (RP) are at greater risk of BCR, and in some instances where suspicious tissue is noted in the prostate bed or when frozen-section analysis shows PSM, additional tissue is resected from the suspect site of the PSM. PATIENTS AND METHODS Between January 1999 and June 2007, 4217 consecutive patients underwent open or laparoscopic RP with no previous radiotherapy or hormonal therapy. The median (interquartile range) follow-up was 37.4 (21.1–60.7) months. RESULTS Pathological organ-confined (OC) cancer was present in 2901 men, of whom 2659 had M−, 216 had M+, and 26 had M+ −. Extracapsular extension (ECE) alone with no seminal vesicle or lymph node involvement was present in 843 men, of whom 657 had M−, 174 had M+ and 12 had M+ −. For patients with OC cancer, the 36-month actuarial BCR-free probability was 97.9% (95% confidence interval 97.3–98.5) for M−, vs 89.0 (84.1–93.9)% for M+ vs 100% for M+ −. For patients with ECE, the 36-month actuarial BCR-free probability was 83.7 (80.0–87.4)% for M− vs 73.7 (66.1–81.3)% for M+ vs 90.0 (71.4–100)% for M+ −. The main limitation of the study was its retrospective nature, with the reason for resection of additional tissue not always well documented. CONCLUSIONS While the few patients with PSMs and further negative resected tissue limited the statistical analysis, it would appear that in these patients the disease behaves as in those with negative margins.
Merton’s Contribution to the Sociology of Science:

This paper is reminiscence and a critique of Robert K. Merton’s work in the sociology of science. The author got to know Merton very well as he served as his student, assistant, and colleague for 15 years from 1960. Merton’s works which are most discussed are his doctoral dissertation on Puritanism and science, his paper on scientific norms, and his paper ‘The Matthew Effect’. He is criticized for not generalizing far enough from his work on the Puritan thesis and for not paying close enough attention to the empirical data, which cast doubt on the validity of his theory of the Matthew Effect.