bluuebunny/crossref_metadata_2025 huggingface dataset:
Exclusive male care despite extreme female promiscuity and low paternity in a marine snail
Authors: Kamel Stephanie J. , Grosberg Richard K.
Published: July 2012

Males exhibit striking variation in the degree to which they invest in offspring, from merely provisioning females with sperm, to providing exclusive post‐zygotic care. Paternity assurance is often invoked to explain this variation: the greater a male's confidence of paternity, the more he should be willing to provide care. Here, we report a striking exception to expectations based on paternity assurance: despite high levels of female promiscuity, males of a marine snail provide exclusive, and costly, care of offspring. Remarkably, genetic paternity analyses reveal cuckoldry in all broods, with fewer than 25% of offspring being sired by the caring male, although caring males sired proportionally more offspring in a given clutch than any other fathers did individually. This system presents the most extreme example of the coexistence of high levels of female promiscuity, low paternity, and costly male care, and emphasises the still unresolved roles of natural and sexual selection in the evolution of male parental care.
Biofilm shows spatially stratified metabolic responses to contaminant exposure
Authors: Cao Bin , Majors Paul D. , Ahmed Bulbul , Renslow Ryan S. , Silvia Crystal P. , Shi Liang , Kjelleberg Staffan , Fredrickson Jim K. , Beyenal Haluk
Published: July 2012

Biofilms are core to a range of biological processes, including the bioremediation of environmental contaminants. Within a biofilm population, cells with diverse genotypes and phenotypes coexist, suggesting that distinct metabolic pathways may be expressed based on the local environmental conditions in a biofilm. However, metabolic responses to local environmental conditions in a metabolically active biofilm interacting with environmental contaminants have never been quantitatively elucidated. In this study, we monitored the spatiotemporal metabolic responses of metabolically active Shewanella oneidensis MR‐1 biofilms to U(VI) (uranyl, UO2
2+) and Cr(VI) (chromate, CrO4
2−) using non‐invasive nuclear magnetic resonance imaging (MRI) and spectroscopy (MRS) approaches to obtain insights into adaptation in biofilms during biofilm‐contaminant interactions. While overall biomass distribution was not significantly altered upon exposure to U(VI) or Cr(VI), MRI and spatial mapping of the diffusion revealed localized changes in the water diffusion coefficients in the biofilms, suggesting significant contaminant‐induced changes in structural or hydrodynamic properties during bioremediation. Finally, we quantitatively demonstrated that the metabolic responses of biofilms to contaminant exposure are spatially stratified, implying that adaptation in biofilms is custom‐developed based on local microenvironments.
Direct renin inhibition improves parasympathetic function in diabetes
Authors: Maser R. E. , Lenhard M. J. , Kolm P. , Edwards D. G.
Published: July 2012

Aim

The renin‐angiotensin‐aldosterone system (RAAS) and autonomic nervous system regulate the cardiovascular system. Blockade of the RAAS may slow the progression of end‐organ damage. Direct renin inhibition offers a means for blocking the RAAS. The objective of this study was to examine the effect of direct renin inhibition on cardiovascular autonomic function.

Methods

In this double‐blind, placebo‐controlled trial, 60 individuals with diabetes were randomly assigned to 300 mg of aliskiren or placebo once daily for 6 weeks. The primary end point was a change in tests of cardiovascular autonomic function. Autonomic function was assessed by power spectral analysis and RR‐variation during deep breathing [i.e. mean circular resultant (MCR), expiration/inspiration (E/I) ratio]. The MCR and E/I ratio assess parasympathetic function. Secondary measures included change in biochemical parameters [e.g. plasma renin activity, leptin and interleukin‐6]. Change in cardiovascular autonomic function and blood analytes were analysed by a mixed effects model for repeated measures.

Results

Baseline characteristics were similar between treatment groups. In response to aliskiren compared with placebo, blood pressure was reduced as well as plasma renin activity [from 2.4 ± 3.8 (mean ± standard deviation) to 0.5 ± 0.4 µg/l/h, p < 0.001]. There was a significant interaction (aliskiren × visit) for MCR (p = 0.003) and E/I ratio (p = 0.003) indicating improvement in MCR and E/I ratio for those on aliskiren. MCR means, baseline vs. follow‐up, were 41.8 ± 19.7 vs. 50.8 ± 26.1 (aliskiren) and 38.2 ± 23.6 vs. 37.5 ± 24.1 (placebo).

Conclusions

Parasympathetic function (i.e. MCR and E/I ratio) was enhanced by downregulation of the RAAS.
Fish life history, angler behaviour and optimal management of recreational fisheries
Authors: Johnston Fiona D , Arlinghaus Robert , Dieckmann Ulf
Published: July 2012

To predict recreational‐fishing impacts on freshwater fish species, it is important to understand the interplay between fish populations, anglers and management actions. We use an integrated bioeconomic model to study the importance of fish life‐history type (LHT) for determining (i) vulnerability to over‐exploitation by diverse angler types (generic, consumptive and trophy anglers), who respond dynamically to fishing‐quality changes; (ii) regulations [i.e., minimum‐size limits (MSLs) and licence densities] that maximize the social welfare of angler populations; and (iii) biological and social conditions resulting under such socially optimal regulations. We examine five prototypical freshwater species: European perch (Perca fluviatilis), brown trout (Salmo trutta), pikeperch (Sander lucioperca), pike (Esox lucius) and bull trout (Salvelinus confluentus). We find that LHT is important for determining the vulnerability of fish populations to overfishing, with pike, pikeperch, and bull trout being more vulnerable than perch and brown trout. Angler type influences the magnitude of fishing impacts, because of differences in fishing practices and angler‐type‐specific effects of LHT on angling effort. Our results indicate that angler types are systematically attracted to particular LHTs. Socially optimal minimum‐size limits generally increase with LHT vulnerability, whereas optimal licence densities are similar across LHTs. Yet, both regulations vary among angler types. Despite this variation, we find that biological sustainability occurs under socially optimal regulations, with one exception. Our results highlight the importance of jointly considering fish diversity, angler diversity and regulations when predicting sustainable management strategies for recreational fisheries. Failure to do so could result in socially suboptimal management and/or fishery collapse.
CO‐INTEGRATING VAR MODELS AND ECONOMIC POLICY
Authors: Carlucci Francesco , Montaruli Francesco
Published: July 2012

This paper surveys some relevant contributions to the economic literature on co‐integrating vector autoregressive (VAR) models [vector error correction mechanisms (VECMs)], emphasizing their usefulness for economic policy. It further discusses some theoretical aspects that are necessary for a complete understanding of their potential. The theoretical introduction of the co‐integrating VAR model is followed by an illustration of its applications to monetary policy, fiscal policy and exchanges rates as well as in establishing the effects of structural bilateral shocks between countries (the so‐called global VAR, or GVAR, models). Special attention is paid to the VECM capacities of being used in conjunction with dynamic stochastic general equilibrium models and of jointly specifying the short‐ and long‐run dynamics, thus representing the steady‐state of economic systems (by means of the co‐integration relations) and the short‐run dynamics around it.
Defensive Practice Adoption in the Face of Organizational Stigma: Impression Management and the Diffusion of Stock Option Expensing
Authors: Carberry Edward J. , King Brayden G
Published: July 2012

Although most diffusion research focuses on firms adopting new practices to maintain their legitimacy, this paper examines a setting in which firms adopted a controversial practice to defend themselves against challenges relating to corporate deviance. We argue that understanding defensive adoption requires attending to both the dynamics of organizational stigma and impression management, and test our theoretical claims by analysing the diffusion of an accounting practice, stock option expensing (SOPEX), following the Enron scandal. We first provide evidence that the media and shareholder activists transformed the practice into a defensive device by theorizing it as a solution to problems relating to corporate fraud and corporate governance. Using event history analysis, we then show that corporations that became targets of stigma‐inducing threats were more likely to adopt SOPEX and that the media were a key force channelling these threats.
Flows, Friction and the Sociomaterial Metabolization of Alcohol
Authors: Lawhon Mary
Published: July 2012

Abstract: Political ecologists have considered the sociomateriality of diverse hybrids and the metabolism and circulation of urban flows such as water, food and waste. Adding alcohol to this list enhances our understanding of the geography of alcohol as well as the theory of sociomateriality. Viewing alcohol as a sociomaterial hybrid draws attention to the power‐laden, dynamic processes which shape its flow, rather than considering it as already in place. Additionally, my examination of alcohol calls attention to aspects of sociomateriality which are widely relevant but underexplored in the literature: the role of friction in shaping flows; the need to examine microscale impacts of sociomateriality on the body and community; and the conditional impacts of complex, unpredictable sociomaterial hybrids. I use a case study of alcohol in Cape Town to examine how alcohol flows, encounters friction, flows over boundaries and shapes sociability and harm in complex, indeterminate ways.

Studies of alcohol typically focus on either its negative impacts on health and wellbeing or positive impacts on economic development, while policy debates focus on whether and how to control access. In this paper, I move beyond these binaries to provide a more nuanced, grounded articulation of how alcohol flows and what inhibits its flow. I examine the distribution of power and agency, limitations of state regulation, willingness of community members to act outside of and with little fear of the law, and the specificity of alcohol as a highly desirable commodity which easily flows around artificial barriers. These insights help clarify relationships, power and the (in)efficacy of policy efforts, and suggest the need to refocus debates. The paper is unable to provide specific policy recommendations, but instead argues that a better understanding of flows and frictions can move the focus from alcohol control to reducing alcohol‐related harm.
A number‐of‐modes reference rule for density estimation under multimodality
Authors: Einbeck Jochen , Taylor James
Published: July 2012

We consider kernel density estimation for univariate distributions. The question of interest is as follows: given that the data analyst has some background knowledge on the modality of the data (for instance, ‘data of this type are usually bimodal’), what is the adequate bandwidth to choose? We answer this question by extending Silverman's idea of ‘normal‐reference’ to that of ‘reference to a Gaussian mixture’. The concept is illustrated in the light of real data examples.
Probabilistic Index Models
Authors: Thas Olivier , Neve Jan De , Clement Lieven , Ottoy Jean-Pierre
Published: July 2012

We present a semiparametric statistical model for the probabilistic index which can be defined as P(Y⩽Y*), where Y and Y* are independent random response variables associated with covariate patterns X and X* respectively. A link function defines the relationship between the probabilistic index and a linear predictor. Asymptotic normality of the estimators and consistency of the covariance matrix estimator are established through semiparametric theory. The model is illustrated with several examples, and the estimation theory is validated in a simulation study.
Mann–Whitney Test with Adjustments to Pretreatment Variables for Missing Values and Observational Study
Authors: Chen Song Xi , Qin Jing , Tang Cheng Yong
Published: July 2012

The conventional Wilcoxon or Mann–Whitney test can be invalid for comparing treatment effects in the presence of missing values or in observational studies. This is because the missingness of the outcomes or the participation in the treatments may depend on certain pretreatment variables. We propose an approach to adjust the Mann–Whitney test by correcting the potential bias via consistently estimating the conditional distributions of the outcomes given the pretreatment variables. We also propose semiparametric extensions of the adjusted Mann–Whitney test which lead to dimension reduction for high dimensional covariates. A novel bootstrap procedure is devised to approximate the null distribution of the test statistics for practical implementations. Results from simulation studies and an economics observational study data analysis are presented to demonstrate the performance of the approach proposed.
New Local Estimation procedure for a Non-Parametric Regression Function for Longitudinal Data
Authors: Yao Weixin , Li Runze
Published: July 2012

The paper develops a new estimation of non-parametric regression functions for clustered or longitudinal data. We propose to use Cholesky decomposition and profile least squares techniques to estimate the correlation structure and regression function simultaneously. We further prove that the estimator proposed is as asymptotically efficient as if the covariance matrix were known. A Monte Carlo simulation study is conducted to examine the finite sample performance of the procedure proposed, and to compare the procedure with the existing procedures. On the basis of our empirical studies, the newly proposed procedure works better than naive local linear regression with working independence error structure and the gain in efficiency can be achieved in moderate-sized samples. Our numerical comparison also shows that the newly proposed procedure outperforms some existing procedures. A real data set application is also provided to illustrate the estimation procedure proposed.
Kind of Black: The Musicians' Labour Market in Italy
Authors: Balestrino Alessandro
Published: July 2012

It is estimated that only 5 per cent of musicians in Italy are regularly employed. In an attempt at understanding such a peculiar situation, we build a theoretical model of the musicians' labour market in which we embed the main institutional features of the Italian system. The presence of taxation encourages the formation of a black labour market for musicians and discourages talented agents from becoming full‐time musicians in all second‐best economies. In Italy both tendencies are particularly strong, and exacerbated by the peculiarities of the pension system for musicians. These inefficiencies might be corrected by a twofold policy: the reform of the pension system, highly desirable but unlikely to be politically feasible in the current Italian institutional setting, and the introduction of a sufficiently large unemployment benefit for musicians, step that has a general interest for any second‐best economy and not only for the case of the musicians' labour market, and that might instead be viable under certain circumstances.
Two‐Factor Decomposition Analysis for Correlation between Mainland China and Hong Kong Stock Markets
Authors: Wang Kent , Miao Li , Li Jiawei
Published: July 2012

We analyzed the correlation between mainland China and Hong Kong stock markets based on cash flow (CF) news and discount rate (DR) news instead of considering market return as a whole. We decomposed stock return into CF news and DR news following Campbell and Vuolteenaho. Then, the VAR‐ BEKK‐GARCH method was used to investigate the time‐varying correlations of CF news and DR news in the two markets. We ensured robustness by using the structural break test from Bai and Perron to estimate the structural break points during the sample period. The results show that CF news and DR news in the mainland China market is more volatile than in the Hong Kong market, and DR news correlation is usually negative when the mainland China market is undergoing some reform. The estimated structural break points were matched to important events in the mainland China market and the two markets become increasingly correlated.
The substance of love when encountering suffering: an interpretative research synthesis with an abductive approach
Authors: Thorkildsen Kari Marie , Eriksson Katie , Råholm Maj‐Britt
Published: July 2012

Scand J Caring Sci; 2013; 27; 449–459

The substance of love when encountering suffering: an interpretative research synthesis with an abductive approach

Aim:  This study presents the results of an interpretative research synthesis undertaken to explore the essence of love when encountering suffering. The idea of caring as an expression of love and compassion belongs with ideas that have shaped caring for hundreds of years. Love and suffering are the core concepts in caring science and thus demand a basic research approach.

Methods:  The synthesis was undertaken by the interpretation of 15 articles focusing on love in different aspects, but within a caring science perspective. The research process was guided by a hermeneutical perspective with an abductive approach.

Results:  The substance of love, when encountering suffering, reveals itself in three themes: love as a holy power, love as fundamental for being and love as an ethical act, which are to be found, respectively, within three dimensions: love as holiness, love as a communion and love as an art. Love is a holy power and encompasses everything; it is the well of strength that heals. No human can exist without love: this points to the ethical responsibility one has as a neighbour. In the ethical act, love is evident in concrete caring actions.

Conclusions:  The core of the substance of love within the three dimensions can be understood as agape. Agape connects and mirrors the dimensions, while at the same time it is clear that agape stems from and moves towards holiness, enabling love to be the ethical foundation when encountering suffering. Through the dimensions of love as communion and love as an art agape intertwine with eros forming caritas enabling the human being to move towards the dimension of holiness, which signifies becoming through suffering.
Effect of social support on changes in quality of life in early breast cancer patients: a longitudinal study
Authors: Salonen Päivi , Tarkka Marja‐Terttu , Kellokumpu‐Lehtinen Pirkko‐Liisa , Koivisto Anna‐Maija , Aalto Pirjo , Kaunonen Marja
Published: July 2012

Scand J Caring Sci; 2013; 27; 396–405

Effect of social support on changes in quality of life in early breast cancer patients: a longitudinal study

Background:  Breast cancer diagnosis as well as diversity of the treatment process deteriorates women’s quality of life (QOL). Researchers have examined social support and its relations with QOL overall, but less is known about effects of social support on changes in QOL.

Aims:  The aim of this study was to examine social support received from social network and nurses within 6 months and QOL in women with breast cancer.

Methods:  Women (N = 164) after breast cancer surgery were quasi‐randomized to the intervention (n = 85) and control groups (n = 79). Participants completed two well‐known QOL questionnaires, and the questionnaire measuring received social support from network and from nurses both 1 week and 6 months after the breast cancer surgery. Data were analysed using descriptive statistics and nonparametric tests. Logistic regression model with the enter method was employed to identify associations between social support and negative changes in QOL.

Results:  Affect and aid from network decreased in both groups and affirmation in the intervention group within 6 months. No significant changes in received social support from nurses were found within groups. Furthermore, no statistically significant difference in the magnitude of changes over time was found between groups. Received social support had an effect on changes in sexual functioning, global QOL and health and functioning.

Conclusions:  Received social support decreased in both groups within 6 months. Significant effects of social support on negative changes on QOL were found. Social support tailored to women’s individual needs is an essential part of the care in patients with breast cancer. For further research, longitudinal designs for longer period should be established to explore social support and its effects on QOL.
The pivotal role of tumour necrosis factor α in the development of inflammatory hyperalgesia
Authors: Cunha F.Q. , Poole S. , Lorenzetti B.B. , Ferreira S.H.
Published: July 2012

The hyperalgesic activities in rats of interleukin‐1β (IL‐1β), IL‐6, IL‐8, tumour necrosis factor α (TNFα) and carrageenin were investigated.

IL‐6 activated the previously delineated IL‐1/prostaglandin hyperalgesic pathway but not the IL‐8/sympathetic mediated hyperalgesic pathway.

TNFα and carrageenin activated both pathways.

Antiserum neutralizing endogenous TNFα abolished the response to carrageenin whereas antisera neutralizing endogenous IL‐1β, IL‐6 and IL‐8 each partially inhibited the response.

The combination of antisera neutralizing endogenous IL‐1β + IL‐8 or IL‐6 + IL‐8 abolished the response to carrageenin.

These results show that TNFα has an early and crucial role in the development of inflammatory hyperaglesia.

The delineation of the roles of TNFα, IL‐1β, IL‐6 and IL‐8 in the development of inflammatory hyperalgesia taken together with the finding that the production of these cytokines is inhibited by steroidal anti‐inflammatory drugs provides a mechanism of action for these drugs in the treatment of inflammatory hyperalgesia.
Characterization of adenosine receptors in brush‐border membranes from pig kidney
Authors: Blanco Julià , Canela Enric I. , Mallol Josefa , Lluís Carmen , Franco Rafael
Published: July 2012

The adenosine receptors from pig kidney proximal tubules have been studied in membrane vesicle preparations derived from either luminal (brush‐border membranes‐BBM‐) or basolateral (BL) sides. There was a substantial amount of A2‐like NECA binding in both preparations, but the A1 subtype of adenosine receptors was not found in either BBM or BL membranes. The use of [3H]‐CGS21680 which is a more specific ligand for A2a receptors revealed true adenosine receptors in the BBM.

The kinetic parameters for [3H]‐CGS21680 binding to pig renal BBM were: Bmax = 1.48 pmol mg−1 protein and Kd = 150 nm. In the presence of Gpp(NH)p the affinity decreased (Kd = 220 nm), whereas the addition of Mg2+ induced a marked increase in affinity (Kd = 83 nm). These equilibrium constants are higher than those found for the A2a adenosine receptors present in pig brain striatal membranes (Kd = 12 nm), and are close to those found in rat renal BBM (Kd = 90 nm).

The order of potency of agonist and antagonists was not consistent with the presence of either A1 or A2 receptors, but it was very similar to the agonist order of potency for the A3 receptor subtype. Furthermore, the blockade of the [3H]‐CGS21680 binding by both cholera and pertussis toxin further supports the view that the subtypes present in BBM are neither A1 nor A2.

Overall the results suggest the presence in BBM of an A3 receptor, or of a new subtype of adenosine receptor, which is linked to G proteins sensitive to both cholera and pertussis toxins.
A possible role of decreased relaxation mediated by β‐adrenoceptors in bladder outlet obstruction by benign prostatic hyperplasia
Authors: Tsujii Toshihiko , Azuma Hiroshi , Yamaguchi Tomohiro , Oshima Hiroyuki
Published: July 2012

To explore mechanisms of urinary obstruction in benign prostatic hyperplasia (BPH), the features of contraction and relaxation in human hyperplastic and non‐hyperplastic (control) prostatic tissues were investigated for β‐ and α1‐adrenoceptors by radioligand binding and in vitro isometric tension experiments.

Hyperplastic and control prostatic tissues had a similar number (per mg protein) of prazosin binding sites with similar affinities. Noradrenaline (NA) induced dose‐dependent contraction in both tissues. Contraction induced by either exogenous NA or transmural stimulation was inhibited by prazosin in both tissues, indicating that the same contractile mechanisms mediated by α1‐adrenoceptors exist in hyperplastic and control tissues.

The number of dihydroalprenolol (DHA) binding sites (per mg protein) was less in hyperplastic tissues than in controls, whereas the affinity to the ligand was identical in both tissues. Isoprenaline caused a marked relaxation of the tonic contraction induced by KCl in control tissues, but not in hyperplastic tissues. Propranolol enhanced exogenous NA‐ or transmural stimulation‐induced contraction more in control tissues than in hyperplastic tissues. Both tissues, however, similarly responded to forskolin by relaxation.

These results indicate that decreased β‐adrenoceptor‐mediated relaxation in hyperplastic prostatic tissues, which is attributable at least in part to the decreased number of β‐adrenoceptors, may play a role in the urinary obstruction of BPH in addition to mechanical compression of the urethra by the enlarged prostate.
Neurokinin A‐induced contraction of guinea‐pig isolated trachea: potentiation by hepoxilins
Authors: Laneuville Odette , Couture Réjean , Pace‐Asciak Cecil R.
Published: July 2012

Hepoxilin A3 (8R and 8S isomers) (HxA3), hepoxilin A3‐C (8R and 8S isomers) (HxA3‐C) and trioxilin A3 (8S isomer) (TrXA3, the stable derivative of HxA3) were tested for their effects on helicoidal strips of guinea‐pig isolated tracheae.

None of the compounds (10−9−10−6 m) tested had a direct effect on resting tension of trachea.

HxA3 (8S) and HxA3‐C (8R) (10−8 m) produced a significant leftward shift of the log concentration‐response curves to neurokinin A (NKA) (EC50 (n m), control = 29.0 ± 2.8, HxA3 (8S) = 21.7 ± 3.7, HxA3‐C (8R)= 13.8 ± 3.8, n = 6 for each). Also the maximal response to NKA was significantly increased when the tissues were exposed to these hepoxilins (% of the maximal response to NKA, control = 100, HxA3 (8S) = 114.5 ± 5.3, HxA3‐C (8R) = 139.0 ± 6.2, n = 6 for each). The threshold concentrations for both hepoxilins was 10−8 m and their effects were dose‐related.

Stereochemical specificity was observed. The 8S‐isomer of HxA3 was active in potentiating the NKA‐induced contraction of the trachea while the 8R isomer was inactive. In contrast, the 8R isomer of HxA3‐C was active while the 8S isomer was inactive. The trihydroxy metabolite of the active isomer of HxA3 (8S), i.e. TrXA3 (8S) (10−6 m), was inactive in potentiating the NKA‐induced contraction of the trachea.

It is concluded that hepoxilins sensitize the guinea‐pig isolated trachea to the potent bronchoconstrictor, NKA.
Inhibition of the haemodynamic effects of angiotensin II in conscious rats by AT2‐receptor antagonists given after the AT1‐receptor antagonist, EXP 3174
Authors: Widdop R.E. , Gardiner S.M. , Kemp P.A. , Bennett T.
Published: July 2012

Conscious, Long Evans rats (n = 10), chronically instrumented for the measurement of regional haemodynamics, were studied on 3 consecutive experimental days to assess responses to angiotensin II (AII) (125 pmol kg−1, i.v.) and noradrenaline (1 nmol kg−1, i.v.) in the absence and presence of the AT2‐receptor antagonist, PD 123319 (10 mg kg−1, i.v.) (day 1), the AT1‐receptor antagonist, EXP 3174 (1 mg kg−1, i.v.) (day 2), and PD 123319 (10 mg kg−1, i.v.) given 24 h after EXP 3174 (day 3).

In naive rats (day 1), PD 123319 did not antagonize the haemodynamic effects of AII or noradrenaline. EXP 3174 (day 2) caused a marked, prolonged blockade of the haemodynamic effects of AII but not those of noradrenaline. Twenty four h after administration of EXP 3174 (day 3) there was still significant attenuation of the haemodynamic effects of AII. However, administration of PD 123319 at this time caused a further inhibition (lasting 1 h) of the effects of AII but not those of noradrenaline.

An identical 3 day protocol was used in a separate group of rats (n = 6) in which the AT2‐receptor antagonist, PD 123177, was given instead of PD 123319, and the results were essentially the same, i.e., PD 123177 significantly attenuated the haemodynamic effects of AII but only when given 24 h after EXP 3174.

In a separate group of rats (n = 4), a low dose of EXP 3174 (60 μg kg−1 i.v.) was given to naive rats in order to simulate the degree of inhibition of the effects of AII seen after administration of AT2‐receptor antagonists in animals pretreated with EXP 3174. This low dose of EXP 3174 did not produce a sustained inhibition of the effects of AII and the time course of recovery of AII responses was similar to that seen with PD 123319 or PD 123177 given after the high dose of EXP 3174.

The apparent inhibition of the effects of AII by the AT2‐receptor antagonists, PD 123319 and PD 123177, when these were administered 24 h after the AT1‐receptor antagonist, EXP 3174, may have been due to the functional activation of AT2‐receptors and/or loss of AT2‐receptor antagonist selectivity, and/or the displacement of nonspecifically bound EXP 3174 by AT2‐receptor antagonists. While the latter explanation seems the most likely, these results raise the possibility that nonpeptide, AII‐receptor antagonists that act at both AT1‐ and AT2‐receptors may have therapeutic advantages over selective AT1‐receptor antagonists.
Muscarinic blockade of β‐adrenoceptor‐stimulated adenylyl cyclase: the role of stimulatory and inhibitory guanine‐nucleotide binding regulatory proteins (Gs and Gi)
Authors: Pyne Nigel J. , Grady Michael W. , Shehnaz Darakhshanda , Stevens Patricia A. , Pyne Susan , Rodger Ian W.
Published: July 2012

The functional antagonism that exists between muscarinic and β‐adrenoceptor function in guinea‐pig tracheal smooth muscle was investigated by assessing Gs and Gi regulated adenylyl cyclase activity in isolated membranes.

Membranes from guinea‐pig tracheal smooth muscle contain both Giα and Gsα as assessed by Western blots with anti‐G‐protein antibodies.

GppNHp, a non‐hydrolysable analogue of guanosine 5′‐triphosphate (GTP), was shown to stimulate adenylyl cyclase activity at high concentrations (10−6−10−4 m). GppNHp also produced a concentration‐dependent reduction in pertussis toxin‐catalysed adenosine diphosphate (ADP)‐ribosylation of Giα.

Pretreatment of tracheal smooth muscle slices with methacholine (10−6 m) provoked a blockade of isoprenaline plus GTP, GppNHp‐ and GTP‐stimulated adenylyl cyclase.

Addition of methacholine to membranes did not trigger inhibition of GTP‐stimulated adenylyl cyclase activity but did block the isoprenaline‐mediated augmentation of GTP‐stimulated adenylyl cyclase activity.

Pretreatment of tracheal smooth muscle with methacholine (10−6 m) provoked a blockade of cholera toxin‐catalysed NAD+‐dependent ADP‐ribosylation of Gsα.

Phorbol‐12‐myristate 13‐acetate (PMA)‐treatment of tracheal smooth muscle slices actually enhanced GppNHp‐stimulated adenylyl cyclase activity in subsequently prepared membranes.

We suggest that methacholine in addition to inhibiting adenylyl cyclase via a Gi‐dependent mechanism induces a functional inactivation of Gs activity. These results together may explain the functional antagonism that exists between increased muscarinic tone and the ability of β‐adrenoceptor agonists to provoke excitation‐contraction uncoupling.
Comparison of the Effects of Three Cell Saver Devices on Erythrocyte Function During Cardiopulmonary Bypass Procedure—A Pilot Study
Authors: Wang Xiaohua , Ji Bingyang , Zhang Yanwan , Zhu Xian , Liu Jinping , Long Cun , Zheng Zhe
Published: July 2012

Cell salvage devices are routinely used to process red blood cells (RBCs) shed during cardiac surgery. The purpose of this study was to evaluate three commercially available cell saver (CS) devices in terms of erythrocyte function and the quality of washed RBCs during cardiopulmonary bypass (CPB). Thirty patients undergoing CPB were randomly allocated to three CS devices: Group C (Cell Saver 5+; Haemonetics, n = 10), Group M (autolog; Medtronic, n = 10), and Group F (CATS; Fresenius HemoCare, n = 10). Blood samples were collected from reservoirs and transfusion bags. Reservoirs and washed RBCs were analyzed for erythrocyte aggregation index, deformation index (DI) and hematocrit viscosity, 2,3‐diphosphoglycerate (2,3‐DPG), hematocrit (Hct), hemoglobin (Hb), free Hb removal (ΔfHb), glucose (Glu), lactate (Lac), and blood urea nitrogen. After processing, Groups C (P = 0.026) and M (P = 0.032) had relatively higher erythrocyte DI compared with Group F. Group C had lower Δ2,3‐DPG compared with Groups M (P = 0.001) and F (P = 0.001). Group F provided the maximum concentration of Hct (P = 0.021; 0.046) and Hb (P = 0.008; 0.013). In addition, Groups C (P = 0.035) and M (P = 0.038) had a higher removal of fHb (ΔfHb), differing significantly with Group F. In conclusion, CS devices use the same theory of centrifugation; however, based on different designs, the function of the washed erythrocyte and undesirable content removal efficiency differs widely from one device to another.
The Progressive Wave Pump: Numerical Multiphysics Investigation of a Novel Pump Concept With Potential to Ventricular Assist Device Application
Authors: Perschall Markus , Drevet Jean Baptiste , Schenkel Torsten , Oertel Herbert
Published: July 2012

This article describes the numerical fluid–structure interaction (FSI) validation of a new pumping concept and the possibility for application of a further developed type, as an implantable ventricular assist device (VAD). The novel principle of the so‐called progressive wave pump is based on the interaction of an elastic membrane actuated by forced excitation with a surrounding fluid and the pump housing. By applying forced vibrations to one end of the membrane, a transversal wave builds up and progresses to the far end generating both a positive pressure gradient and flow rate. Among others, two axisymmetric geometrical configurations are possible, namely the discoidal and the tubular design. The first one has been built as a physical prototype and is experimentally investigated. In addition, a corresponding numerical FSI model is set up and validated against the experimental findings. Based on this validated numerical method, further numerical investigations are conducted focusing on the development of a tubular progressive wave pump concept with regard to its potential for application as a VAD in the future. To address VAD‐relevant issues such as size, hydraulic performance, and blood trauma, corresponding numerical simulations involving macroscopic blood trauma models have been performed. Although being still in an early phase of development, the results are promising and indicate that the wave pump concept in its present state is feasible and can be further developed and investigated as a new type of blood pump.
Monetary Policy and Automatic Stabilizers: The Role of Progressive Taxation
Authors: MATTESINI FABRIZIO , ROSSI LORENZA
Published: July 2012

We study the effects of progressive labor income taxation in an otherwise standard New Keynesian (NK) model. We show that progressive taxation (i) introduces a trade‐off between output and inflation stabilization and affects the slope of the Phillips Curve, (ii) acts as automatic stabilizer changing the responses to technology shocks and demand shocks, and (iii) alters the prescription for the optimal monetary policy. The welfare gains from commitment decrease as labor income taxes become more progressive. Quantitatively, the model reproduces the observed negative correlation between the volatility of output, hours, and inflation and the degree of progressivity of labor income taxation.
Credit Risk Spreads in Local and Foreign Currencies
Authors: GALAI DAN , WIENER ZVI
Published: July 2012

Governments, corporations, and even small firms raise and denominate capital in different currencies. We examine the micro‐level factors that should be considered by a borrower when structuring debt denominated in various currencies. This paper will show how the currency composition of debt affects the cost of debt through the interaction with the risk of company's assets. We look at the currency mismatch in the firm and analyze its credit spread within a Merton's type model with bankruptcy. We show that foreign currency borrowing is cheaper when the exchange rate is positively correlated with the return on the company's assets. The determining factor is not just whether a given company is an exporter or importer, but rather the statistical correlation between the rate of return on the firm's assets and changes in the exchange rate.
Real Balance Effects, Timing, and Equilibrium Determination
Authors: STOLTENBERG CHRISTIAN A.
Published: July 2012

By assuming that money balances at the beginning instead of at the end of the period provide transaction services, standard results on nominal and real determinacy in monetary models are overturned. The key is that predetermined real money balances can be a state variable. Whereas the determination of the absolute price level typically depends on fiscal policy under an exogenous interest setting, nominal determinacy is now achieved even when fiscal policy is Ricardian. Also, in contrast to the Taylor principle, the interest rate policy should respond passively to changes in inflation, thus ensuring nonoscillatory and locally stable equilibrium sequences.
Nocturnal enuresis in children in Kinshasa, Democratic Republic of Congo
Authors: Aloni Michel N , Ekila Mathilde B , Ekulu Pépé M , Aloni Muriel L , Magoga Kumbundu
Published: July 2012

Aim:  To determine the prevalence of nocturnal enuresis in children of Kinshasa in Democratic Republic of Congo.

Methods:  In all, 506 questionnaires were sent to parents of children aged 6–12 years randomly selected from four primary schools in Kinshasa, Democratic Republic of Congo. The questionnaire was designed to collect information about prevalence and factors associated with nocturnal enuresis.

Results:  A total of 415 (82.0%) were correctly completed. In this series, 109 children were identified as nocturnal enuresis in which 50 boys and 56 girls (p > 0.05). Factors associated with nocturnal enuresis were deep sleep, young age and familial history of enuresis (p < 0.05). Only 11% of patients have been consulted by doctors. Twelve children (11.0%) were treated by healers traditional. In the other part, 43 children (39.4%) were frequently punished by their parents. The common self‐help strategies were 79 children (72.5%) were submitted to fluid restrictions before going to sleep and 68 (62.4%) were waking the child at night to void.

Conclusion:  In Kinshasa, the prevalence of nocturnal enuresis was high to those reported in Asian and Western countries. Nocturnal enuresis remains an important clinical problem in children but only a small percentage of parents seek medical help.
Solubility Enhancement Effect of Cyclodexin on Groundwater Pollutants
Authors: Gao Heng , Blanford William J. , Gao Aifang
Published: July 2012

Cyclodextrin (CD) molecules are polycyclic glucose oligomers that have a hydrophilic exterior and a hydrophobic cavity. This structure provides CD the characteristic of enhancing the solubility of groundwater pollutants. The degree to which CD increases the apparent aqueous solubility of certain chemicals has been defined as the solubility enhancement factor (SEF). In this study, a novel and experimentally simple method has been developed to determine the SEF, which can be mathematically obtained by ratio of apparent and traditional Henry's law constants. The effects of temperature and CD concentration on the SEFs and CD cavity occupation have been investigated. Our results show that SEF values are inversely related to temperature for most examined chemicals, which is consistent with the assertion that the CD‐chemical complexes are less stable at higher temperatures. The exception is toluene that shows the least SEF fluctuation within the temperature range studied (5 to 65 °C). This may indicate that the toluene‐CD complex is particularly stable. As the definition of SEF predicted, linear relationships were found between the SEFs and CD concentrations for all the subject chemicals. The CD cavity occupation fraction at 5 °C were 3.14, 2.55, 2.04, 1.60, and 1.67 times greater than the values at 65 °C for of trichloroethylene, perchloroethylene, bezene, ethylbenze, and o‐xylene, respectively. The fraction of CD cavities occupied was found to be inversely related to the CD concentration for all tested chemicals when pollutant mass are held constant. This study provides important information to accurately evaluate the performance of CD when used for aquifer remediation.
Comparison of macular pigment in patients with age‐related macular degeneration and healthy control subjects – a study using spectral fundus reflectance
Authors: Kaya Semira , Weigert Günther , Pemp Berthold , Sacu Stefan , Werkmeister René Marcel , Dragostinoff Nikolaus , Garhöfer Gerhard , Schmidt‐Erfurth Ursula , Schmetterer Leopold
Published: July 2012

Purpose:  Previous studies have reported an age‐dependent decline of macular pigment optical density (MPOD) as well as a relative lack of MPOD in age‐related macular degeneration (AMD). Results are, however, strongly dependent on the technique used. In this study, we investigated the age dependence of MPOD using spectral fundus reflectance. In addition, we hypothesized that patients with AMD have a reduced MPOD as compared to healthy controls.

Methods:  A total of 85 healthy subjects and 96 patients with AMD were included in this study. The healthy control subjects showed a wide range of ages (mean, 51.6 years; range, 21–79 years). Patients with AMD were significantly older (mean, 71.2 years; range, 50–89 years). Spectral fundus reflectance of the fovea was measured in a 2.3° detection field with a custom built fundus reflectometer. Calculation of MPOD was based on a previously published fundus reflectance model.

Results:  Patients with AMD showed a reduced MPOD (0.35 ± 0.12) as compared to the healthy control group (0.39 ± 0.12, p = 0.013 between groups). No age dependence of MPOD (r = −0.14, p = 0.19) was found in the healthy control group. In the AMD group, however, MPOD declined with age (r = −0.24, p = 0.019).

Conclusions:  This study indicates that MPOD is reduced in patients with AMD. In addition, the data of this study indicate that MPOD is age dependent in AMD patients, but not in healthy controls. Taken together with data indicating that lutein supplementation increases MPOD, this provides a rationale for supplementation of the macular pigments in patients with AMD, although long‐term clinical outcome data are lacking.
Prevalence of behavioral problems and related family functioning among middle school students in an eastern city of China
Authors: Ma Xiquan , Yao Yuhong , Zhao Xudong
Published: July 2012

Introduction

This study was carried out to explore the prevalence of behavioral problems among adolescents in junior high school as well as their families' levels of function or dysfunction that contribute to children's behavioral problems in Mainland China.

Methods

One thousand, four hundred and seventy‐six adolescents (ages 12–17 years) and their families participated in the study. Parents completed a self‐administered questionnaire consisting of the Child Behavior Checklist (CBCL), Family Assessment Device (FAD) and a number of demographic questions. Student's t‐tests, chi‐square tests and stepwise multiple regression models were performed to examine the variables.

Results

The estimated prevalence of behavioral problems was 10.5% based on the cutoff point for behavioral problems according to the CBCL. Behavioral problems identified by the CBCL occurred differently at various developmental stages (F = 10.06, P = 0.007). The study showed that inappropriate affective responsiveness, poor affective involvement and low ability of problem solving in the family were significantly associated with increased risk for externalizing behavior problems and total behavior problems of boys. Inappropriate affective responsiveness and poor communication in the family were significantly associated with increased risk for internalizing problems for boys. Poorly established patterns of family behavior were important factors contributing to the development of externalizing behavior problems, internalizing behavior problems and total behavior problems for girls'.

Discussion

The present findings suggest that functional levels of family are associated with the adolescent's mental health, and that specific family dynamics may influence the development of behavioral problems among adolescents in China.
Taxonomic revision of the Symplocos nakaharae complex (Symplocaceae) with special reference to fruit morphology
Authors: LIU Bo , QIN Hai‐Ning
Published: July 2012

Over 70 species and infraspecific taxa have been described in the Symplocos nakaharae (Hayata) Masam. complex (Symplocaceae), and the taxonomy of this complex has been controversial. To provide a rational taxonomic revision of the complex, extensive field observations were carried out and approximately 800 herbarium specimens, covering the whole distribution range, were examined to evaluate the taxonomic importance of morphological characteristics. Our studies recognized 13 species and one subspecies, including S. boninensis, S. henryi, S. kawakamii, S. lucida, S. nakaharae, S. migoi, S. multipes, S. pergracilis, S. setchuensis, S. shilanensis, S. tanakae, S. tetragona, S. theifolia, and S. lucida subsp. howii comb. nov. One new combination is made and two new synonyms, S. ernestii Dunn var. pubicalyx C. Chen syn. nov. and S. kuroki Nagam. syn. nov., are recognized. Two identification keys are provided, based primarily on flower and fruit characters. Detailed morphological descriptions and geographical distribution information of the 14 taxa are given.
A Mechanism of Extreme Growth and Reliable Signaling in Sexually Selected Ornaments and Weapons
Authors: Emlen Douglas J. , Warren Ian A. , Johns Annika , Dworkin Ian , Lavine Laura Corley
Published: July 2012

Truthful Embellishments

Exaggerated ornaments such as beetle horns, deer antlers, and extreme tail lengths in birds are typically assumed to be subject to sexual selection because they signal the quality of an individual's breeding status—but how?

Emlen
et al.

(p.
860
, published online 26 July) present a general mechanistic model for the evolution of exaggerated traits, proposing that sensitivity to the insulin response pathway can explain variation among individuals. The exaggerated size of such ornaments and their increased variability between individuals are a result of sexual selection for traits that are honest signals of the fitness of the individual.