bluuebunny/crossref_metadata_2025 huggingface dataset:
‘I Might not Live That Long!’ A Study of Young Women's Pension Planning in the UK
Authors: Foster Liam
Published: June 2012

There has been considerable concern about levels of pension saving especially given increases in longevity and rising pension deficits. In particular, the prospects of many future female pensioners have been questioned. As pensions are determined by contributions throughout the life course it is imperative to comprehend the attitudes, knowledge, expectations and savings habits of people from an early age to explore why under‐saving occurs. This is particularly pertinent given recent governments' emphasis on individual responsibility for financial provision in retirement. However, there is little research which focuses specifically on young women's attitudes or planning towards pensions despite considerable concern about the future of women's pensions. This article considers young women's (18–30) attitudes towards pensions and whether they differ according to socio‐economic status by using interviews with 15 women (five in routine and manual occupations, five intermediate, five professional and managerial) about how knowledge and choice, trust, responsibility, risk and uncertainty impact on their pension decisions. It is evident that the ability and willingness of people to contribute to a pension depends, among other things, on the pension offered by employers, the pension requirements in place and immediate financial needs. Therefore this article shows that pension policy needs to take into account women's employment histories, which are often fragmented and diverse, when considering young women's attitudes towards pension saving.
The Gendered Production–Consumption Relation: Accounting for Employment and Socioeconomic Hierarchies in the Colombian Cut Flower Global Commodity Chain
Authors: Patel‐Campillo Anouk
Published: July 2012

Scholarly analyses of the transnationalisation of economic activity have placed women workers as active agents in the production of agro‐export commodities for world markets. Less explored, however, are the roles that women and men play according to specific employment and socioeconomic hierarchies in the production, circulation and consumption of export commodities, and their influence on regime transformation. Building on the literatures on Global Commodity Chains (GCCs) and hegemonic masculinities, I examine the production–consumption relation of export‐oriented cut flowers; I suggest that a gender analysis that accounts for the roles that women and men play in the production, circulation and consumption of this export commodity elucidates the ways in which the gendered production–consumption relation is constituted; and how it is used to reproduce as well as contest the norms and practices associated with neoliberal agriculture, or what is termed the third corporate food regime. As transnational capital seeks to expand into new and emerging markets, understanding the gendered production–consumption relation associated with particular commodities is of utmost importance for creating advocacy campaigns that resonate with citizen‐consumers across the world. This article draws on field research, and on critical interpretations of secondary data.
What Drives the Demand for Temporary Agency Workers?
Authors: Jahn Elke J. , Bentzen Jan
Published: June 2012

As part of the general trend towards increased employment flexibility temporary agency employment has grown steadily in most European countries. The paper examines, first, whether the deregulation of temporary agency employment is responsible for the growth of the flexible staffing industry. Second, we investigate the cyclical behavior of temporary agency employment. Using monthly data for Germany, we show that the liberalization of the law regulating the sector is not the main reason for the surge of this employment form. Our analysis reveals, moreover, that temporary agency employment exhibits strong cyclical behavior and correlates with main economic indicators in real time.
SUFFICIENT CONDITIONS FOR THE STABILITY OF LINEAR DIFFERENCE EQUATIONS*
Authors: FAREBROTHER RICHARD WILLIAM
Published: June 2012

In this paper we show that a set of conditions that are sufficient to ensure the stability of a univariate linear difference equation are closely related to the corresponding set of necessary and sufficient conditions established by Samuelson and Wise.
PATENT LICENSING IN A LEADERSHIP STRUCTURE: COMMENT*
Authors: DIN HONG‐REN , LIANG WEN‐JUNG
Published: June 2012

This comment indicates that the derivation of the fixed fee for licensing both firms in Kabiraj (The Manchester School, Vol. 72 (2004), pp. 188–205) uses a different definition from that in Kamien and Tauman (Quarterly Journal of Economics, Vol. 101 (1986), pp. 471–491) and Kamien et al. (Journal of Mathematical Economics, Vol. 21 (1992), pp. 483–508). It not only points out that this different definition is not reasonable, but also yields interesting new findings that are qualitatively different from those reported in Kabiraj (2004).
PRIVATE AND SOCIAL GAINS IN DELEGATION AND SEQUENTIAL GAMES WITH HETEROGENEOUS FIRMS*
Authors: SCRIMITORE MARCELLA
Published: June 2012

We investigate both quantity and price competition in two differentiated oligopolistic frameworks in which firms are heterogeneous with respect to the ownership structure, i.e. managerial firms compete against entrepreneurial firms, or to the timing decisions, i.e. leaders compete against followers. We show the circumstances under which delegation and sequential strategies, shown to be equivalent under unilateral delegation (Vickers, The Economic Journal, Vol. 95 (1985), pp. 138–147), enable firms to out‐perform their rivals and create scope for welfare gains. The different effects of changes in market structure and the degree of product substitutability on firms' profitability and social welfare are discussed.
Induced first abortion rates before and after HIV diagnosis: results of an Italian self‐administered questionnaire survey carried out in 585 women living with HIV
Authors: Ammassari A , Cicconi P , Ladisa N , Di Sora F , Bini T , Trotta MP , D'Ettorre G , Cattelan AM , Vichi F , d'Arminio Monforte A ,   the DiDi Study Group
Published: June 2012

Objectives

The aim of the study was to investigate whether HIV diagnosis affected reproductive planning over time and to assess independent predictors of abortion overall and following HIV diagnosis.

Methods

Donne con Infezione da HIV (DIDI) is an Italian multicentre study based on a questionnaire survey carried out in 585 HIV‐positive women between November 2010 and February 2011. The incidence and predictors of abortion were measured by person‐years analysis and Poisson regression.

Results

The crude incidence rate of abortion was 18.8 [95% confidence interval (CI) 16.5–21.4] per 1000 person‐years of follow‐up (PYFU). Compared with women who terminated their pregnancy before HIV diagnosis, women who terminated their pregnancy after HIV diagnosis but before 1990 showed a 2.56‐fold (95% CI 1.41–4.65) higher risk. During 1990–1999 and 2000–2010, HIV diagnosis was not significantly associated with outcome [adjusted rate ratio (ARR) 0.93 (95% CI 0.55–1.59) and ARR 0.69 (95% CI 0.32–1.48), respectively]. Age [ARR 0.96 (95% CI 0.94–0.99) per 1 year older] and injecting drug use [ARR 1.38 (95% CI 0.98–1.94)] were found to be predictors of abortion overall. After HIV diagnosis, being on combination antiretroviral therapy [ARR 0.54 (95% CI 0.28–1.02)], monthly income < €800 [ARR 1.76 (95% CI 0.99–3.12)], younger age [ARR 0.95 (95% CI 0.91–1.00) per 1 year older] and fear of vertical transmission [ARR 1.95 (95% CI 1.04–3.67)] were found to be independently associated with abortion.

Conclusions

We observed a higher incidence of abortion compared with data available for the general Italian population. Awareness of HIV diagnosis was predictive of abortion only in the 1980s. Women with HIV infection are still worried about vertical HIV transmission. Interventions promoting HIV screening among women who plan to have an abortion and informative counselling on motherhood planning in the setting of HIV care are needed.
Work–Life Balance and Parenthood: A Comparative Review of Definitions, Equity and Enrichment*
Authors: Gatrell Caroline J. , Burnett Simon B. , Cooper Cary L. , Sparrow Paul
Published: June 2012

This review investigates the problems of definition and inequity with which the literature on parenthood and work–life balance is beset. It analyses research trajectories first within the established disciplines of organizational psychology and the sociologies of work and family practices, and then within the newer field of management studies. Gender, class and difference are singled out as troubling themes, especially in relation to fathers and impoverished parents. A tendency towards mono‐disciplinarity is observed within organizational psychology and sociologies of work and family practices. The review offers explanations for the historic but narrow definition within organizational psychology and sociologies of work and family practices of work–life balance as affecting mainly heterosexual dual‐career parent couples. The authors show how this narrow definition has led to inequities within research. They further identify as limiting the definition of work–life balance to be always ‘problematic’, rather than enriching, among employed parents. Consequently, a three‐factor framework is recommended, through which future studies may address the problems of definition and equity in work–life balance literature, including: a broader definition of work–life balance to include marginalized parents; the defining of parenting and employment as potentially life‐enriching; and a commendation of the transdisciplinary approach within management studies as poised to move debate forward.
Planning, facilitating and evaluating a bereavement group for adults with learning disabilities living in the community
Authors: Borsay Clare , Halsey Mary , Critoph Amy
Published: June 2012

Accessible Summary

Adults with learning disabilities sometimes find it hard to cope when someone they care about dies.

This report talks about an 8‐week group that was run to help four adults with learning disabilities cope with their bereavements.

We asked group members to fill in questionnaires and talked to them about what they liked and did not like about the group.

Everyone found it helpful to share their experiences and learn new ways of coping with their bereavements.

This study evaluates the usefulness of a bereavement group for four adults with learning disabilities. Drawing on the work of Boydenet al. (2009), the current authors planned and facilitated an 8‐week group, held in the local community. Qualitative and quantitative feedback was collected from participants, which indicated that they valued the group as a safe and useful space to talk about their bereavements and to learn skills to manage difficult emotions. This study reports and reflects on the process of establishing the group, developing the session plans, delivering the intervention and collecting feedback.
Audit of group‐based activities in an inpatient assessment and treatment unit for individuals with learning disabilities
Authors: Reynolds Philip , Field Lauren
Published: June 2012

Accessible summary

A series of stand‐alone groups were offered on an assessment and treatment ward for adults with learning disabilities.

The group ran for 9 weeks and involved session themes of relaxation, sensory and physical activities.

All individuals involved reported to have found the sessions useful and enjoyable.

All staff involved reported that the sessions were helpful for the participants.

The sessions helped individuals to improve their mood following the session.

The sessions provided a practical way of introducing therapeutic activity to the ward and developing therapeutic relationships.

This audit is intended to investigate the effectiveness of a series of stand‐alone groups delivered on an inpatient unit for individuals with learning disabilities. Our ward is a specialist assessment and treatment unit that provides brief admissions for clients with a learning disability, mental health difficulties and/or challenging behaviour. The aim of the unit is to develop an understanding of the presenting difficulties, formulate an appropriate intervention plan and implement this with the aim of successfully discharging the client back into the community following the shortest possible admission. Group interventions facilitated on the unit were drawn from a variety of evidence and best practice guidelines relating to specific interventions for individuals with a learning disability (Adv Psychiatr Treat, 11, 2005, 355) and more general interventions within inpatient settings (Clin Psychol Forum, 2009, 200). Nine sessions focused on a variety of relaxation, sensory and physical activity tasks. The objective of the audit is to investigate to what extent these interventions are perceived as helpful and enjoyable by clients and by staff, to investigate any positive effect on client's mood and to determine whether any particular activities were rated more favourably than others. Additional aims of the audit are to further understand some of the practical issues related to delivering group‐based interventions in an inpatient environment, to engage ward staff in the delivery of therapeutic activity and to investigate the use of groups as an effective way of developing therapeutic relationships.
Typhoid Mary in the frogpond: can we use native frogs to disseminate a lungworm biocontrol for invasive cane toads?
Authors: Pizzatto L. , Shine R.
Published: June 2012

Read the Commentaries on this Feature Paper: Is Typhoid Mary a good role model? ; Benefits and costs of using a lungworm parasite to control invasive toads in Australia

Response from the authors: New methods in the battle against cane toads: when should we move from research to implementation?
Applying the tools of ecological immunology to conservation: a test case in the Galapagos sea lion
Authors: Brock P. M. , Hall A. J. , Goodman S. J. , Cruz M. , Acevedo‐Whitehouse K.
Published: June 2012

Infectious disease threatens biodiversity and human health on a global scale, and disease emergence may become more common as humans further encroach on habitats and modify environments. To accurately assess the risk of disease emergence in free‐ranging populations of vertebrates, we require an understanding of the dynamics of immunity in the wild. We applied techniques from the emergent discipline of ecological immunology to describe immune activity and dynamics in the endangered Galapagos sea lion Zalophus wollebaeki, which is threatened simultaneously by disease from domestic animals and fluctuations in food supply driven by unpredictable environmental variation. We compared immune activity from shortly after birth until 2 years of age between two Galapagos sea lion colonies: one heavily influenced by humans and the other on an uninhabited island, using a generalized linear model framework. Controlling for development, immune activity was higher in the human‐impacted colony, as assessed with both humoural and cellular immune components and cumulative and snapshot measures of immune activity. We discuss the possibility that sea lions in the human‐impacted colony are under greater immunostimulatory pressure than those in the comparison colony, which could have implications for individual fitness, colony stability and the risk of disease emergence. The study demonstrates the utility of a generalized and widely applicable approach to quantifying immune activity in wild vertebrates, as it highlights important aspects of the system for targeted analysis and further study.
Constant breeding and low survival rates in the subtropical Striped Frog in southern Brazil
Authors: Hiert C. , Roper J. J. , Moura M. O.
Published: June 2012

Survival and consequent implications for population dynamics in the subtropical Striped Frog Hypsiboas leptolineatus was studied for 1 year in the southern Brazilian state of Paraná. By means of capture‐marking‐recapture, we estimated survival and capture probabilities in an open population. A total of 583 captures of 374 individuals, comprising 96% male (n = 353) and 4% females (n = 21), resulted in daily survival estimates ranging from 0.808 to 0.998 day−1. The number of individuals captured per capture session varied from 8 to 37 (mean = 21) and was correlated with night length, after a two session lag time (r = 0.78). Males were found vocalizing throughout the year, while females were less common and gravid females were only found in November, March and June. Recapture probability was relatively constant at 25% for males, 24% for females and, overall, 29% of males were recaptured at least once. Young individuals were encountered in all months but one and, being extremely small, were impossible to quantify. Thus, the Striped Frog is active and breeding year‐round as indicated by the constant singing of adult males, the few gravid females found at different times and the frequent encounters of young frogs at all times of year. While survival and captures varied throughout the year, the only seasonality was in the number of captures that increased during longer nights. Nonetheless, recapture probability was constant. These dynamics contrast strongly with most anuran species and especially subtropical and temperate species in other places. This first detailed study of population parameters of a subtropical species with its unusual dynamics may suggest that once studied, other species of anurans may also have surprising population dynamics.
Presynaptic kainate receptor‐mediated facilitation of glutamate release involves Ca2+–calmodulin at mossy fiber–CA3 synapses
Authors: Andrade‐Talavera Yuniesky , Duque‐Feria Paloma , Negrete‐Díaz José Vicente , Sihra Talvinder S. , Flores Gonzalo , Rodríguez‐Moreno Antonio
Published: June 2012

J. Neurochem. (2012) 122, 891–899.

Presynaptic kainate receptors (KARs) modulate the release of glutamate at synapses established between mossy fibers (MF) and CA3 pyramidal cells in the hippocampus. The activation of KAR by low, nanomolar, kainate concentrations facilitates glutamate release. KAR‐mediated facilitation of glutamate release involves the activation of an adenylate cyclase/cyclic adenosine monophosphate/protein kinase A cascade at MF–CA3 synapses. Here, we studied the mechanisms by which KAR activation produces this facilitation of glutamate release in slices and synaptosomes. We find that the facilitation of glutamate release mediated by KAR activation requires an increase in Ca2+ levels in the cytosol and the formation of a Ca2+–calmodulin complex to activate adenylate cyclase. The increase in cytosolic Ca2+ underpinning this modulation is achieved, both, by Ca2+ entering via Ca2+‐permeable KARs and, by the mobilization of intraterminal Ca2+ stores. Finally, we find that, congruent with the Ca2+–calmodulin support of KAR‐mediated facilitation of glutamate release, induction of long‐term potentiation at MF–CA3 synapses has an obligate requirement for Ca2+–calmodulin activity.
Recent range expansion of the Argentine ant in Japan
Authors: Inoue Maki N. , Sunamura Eiriki , Suhr Elissa L. , Ito Fuminori , Tatsuki Sadahiro , Goka Koichi
Published: June 2012

Aim

The Argentine ant, Linepithema humile, has been spreading via human activities from its native range in South America across much of the globe for more than a century. This invasive ant was first detected in Japan in 1993. Its successful world‐wide expansion is attributed to a social structure, namely supercoloniality, whereby individuals from separate nests cooperate. Here, we examined the genetic structure of L. humile populations to understand its invasion history.

Location

Japan.

Methods

We analysed mitochondrial DNA of Linepithema humile workers from native and other introduced populations and then integrated previously registered sequences.

Results

Sequencing revealed six haplotypes distributed across its introduced ranges, of which five were present in Japan. The first haplotype was shared by the dominant Japanese, European, North American, Australian and New Zealand supercolonies; the second by the Kobe C supercolony and a Florida population; and the third by the Kobe B and secondary Californian supercolonies and North Carolina colonies. The remaining three haplotypes were each restricted to the Kobe A, Tokyo and Catalonian supercolonies, respectively. Each of the five mutually antagonistic supercolonies was fixed for one of the five haplotypes, and multiple supercolonies were found within a small area.

Main conclusions

The large number of haplotypes found in Japan likely reflects the strong propagule pressure of L. humile resulting from the fact that the country is one of the top five importers of trade commodities world‐wide. The short invasion history of L. humile in Japan could explain the maintenance of genetic diversity of each independent introduction. In addition, our sampling mostly occurred at major international shipping ports that are likely to be primary sites of introduction. The several recently established L. humile populations within a small area in Japan provide an opportunity to identify the sources of introduction and the local patterns of spread.
Ancient relicts or recent dispersal: how long have cycads been in centralAustralia?
Authors: Ingham James A. , Forster Paul I. , Crisp Michael D. , Cook Lyn G.
Published: June 2012

Aim

The geology and hydrology of theCentralRanges ofAustralia provide refuge for more mesic‐adapted taxa unable to survive in the surrounding deserts. Whether this area has been a long‐term refuge for mesic‐adapted taxa is uncertain. Mesic‐adapted taxa in the region have been argued as ‘relicts’, remnants of wet forests once covering the region. This scenario hypothesizes that ‘relicts’ survived in pockets of moist habitat in theCentralRanges as theAustralian arid zone expanded. Here, we test an hypothesis of long‐term occupancy in theCentralRanges for a cycad,Macrozamia macdonnellii, a taxon of conservation concern and also one frequently described as an ‘ancient relict’.

Location

Australia.

Methods

A haplotype network, derived fromDNAsequences of two chloroplast regions, was used to infer the biogeographical history ofMacrozamiaacrossAustralia. Specifically, the question of long‐term occupancy of theCentralAustralianRanges is addressed.

Results

Macrozamia macdonnelliishares a haplotype with five eastern species. However, unique haplotypes restricted to only a part of theMacDonnellRangesInterimBiogeographicRegionalisation ofAustralia region are also present. WesternAustralian species ofMacrozamiaform a lineage distinct from those in the rest ofAustralia.

Main conclusions

The shared haplotype, nested within haplotypes from easternAustralia, indicates thatM. macdonnelliiis relatively recently derived from ancestral lineages of easternAustralia. This starkly contrasts with species ofMacrozamiain WesternAustralia, which show long‐term isolation from those in the east. Unique haplotypes in populations ofM. macdonnelliiindicate that the species has occupied the region for sufficient time to accumulate variation. Furthermore, this variation appears to be geographically structured. If so, it indicates thatM. macdonnelliiis undergoing population differentiation, and possible speciation, in different regions of theMacDonnellRanges. Isolated populations with unique haplotypes might be evolutionarily significant units that should be conserved.
The influence of native versus exotic streetscape vegetation on the spatial distribution of birds in suburbs and reserves
Authors: Ikin Karen , Knight Emma , Lindenmayer David B. , Fischer Joern , Manning Adrian D.
Published: June 2012

Aim

Management practices in the landscape matrix can have significant effects on the spatial distribution of animals within adjacent protected areas. This has been well established in agricultural and forested areas, but less is known about how management of the suburban matrix affects adjacent reserves. We argue that it is critically important to understand the impact of suburban management on reserves, as flawed planning decisions can have negative conservation outcomes and waste limited resources.

Location

Canberra, Australian Capital Territory, Australia.

Methods

We examined bird distribution patterns in suburbs and adjacent reserves to the effects of two suburban management practices: (1) street tree planting and (2) boundary design. We focused on three groups of birds with known responses to urbanization: native urban‐intolerant species (native avoiders), native urban‐tolerant species (native adapters) and exotic urban‐tolerant species (exotic adapters).

Results

We found that suburbs with ≥30% native (Eucalyptus) street trees and reserves adjacent to these suburbs had significantly higher bird species richness, native adapter species richness and probability of reporting exotic adapters than those with exotic trees. The type of street trees, however, did not affect the probability of reporting native avoiders. These species were more likely to be reported when habitat complexity was high. Only native adapters responded to boundary design, with higher species richness when the boundary type was a local or unsealed road as opposed to an arterial road.

Main conclusions

Native street trees provide foraging resources for birds that would be reduced or absent in exotic streetscapes, enabling native streetscapes to support a rich community of birds. Furthermore, native streetscapes increase bird richness and diversity in adjacent reserves. This result has important conservation implications for suburb and reserve management practices. Our study provides evidence that the establishment and retention of native suburban streetscapes is an important management strategy for improved bird conservation.
Clinical pharmacology of single‐ and multiple‐ascending doses of ACT‐178882, a new direct renin inhibitor, and its pharmacokinetic interaction with food and midazolam
Authors: Dingemanse Jasper , Nicolas Laurent , Binkert Christoph
Published: June 2012

This study investigated the tolerability, safety, pharmacokinetics, and pharmacodynamics of ACT‐178882, a new direct renin inhibitor, as well as its interaction with food and midazolam. Healthy male subjects received either single (10–1000 mg) or multiple doses (30–600 mg) administered once daily for 14 days of ACT‐178882, placebo, or 20 mg enalapril in the fasted state. Following a 2‐week washout, the single dose of 30 mg ACT‐178882 was also administered in the fed state. In the multiple‐ascending‐dose part, subjects were dosed with midazolam on days −2, 2, and 12 to investigate interactions with CYP3A4. Dizziness and headache were the most frequently reported adverse events. No clinically relevant changes occurred for body weight, vital signs, clinical laboratory variables, and ECG although both enalapril and ACT‐178882 tended to decrease systolic blood pressure. Following single doses of ACT‐178882, t1/2 and tmax varied from 18.7 to 24.7 h and from 3 to 5 h, respectively, and food had no significant effect. Steady‐state conditions were achieved after 4–6 days of dosing and accumulation was minimal. ACT‐178882 pharmacokinetics were dose proportional. ACT‐178882 but not enalapril dose‐dependently increased Cmax and area under the concentration‐time curve of midazolam. Single and multiple doses of ACT‐178882 dose‐dependently increased active renin and decreased plasma renin activity, whereas enalapril increased both variables. No effects on urinary excretion of creatinine, potassium, and the 6β‐hydroxycortisol/cortisol ratio were observed, whereas sodium and aldosterone excretion was decreased by both ACT‐178882 and enalapril. The current results with ACT‐178882 warrant further clinical investigation of this renin inhibitor in hypertensive patients.
Various strategies to handle cannibalization in a competitive duopolistic market
Authors: Haruvy Ernan E. , Miao Di , Stecke Kathryn E.
Published: June 2012

We investigate an incumbent's optimal sequential introduction of new products over two periods in a competitive duopoly setting. The firm would like to preempt and counter competition from a future entrant. Alternatively, the firm should consider that one of its products might decrease sales for another of their products, a threat commonly known as cannibalization. In this paper, we examine three sequential introduction strategies. We find that a firm's optimal introduction sequence is governed by pressures from competition and cannibalization in the market. In general, competition has greater impact on firms’ profits than cannibalization. Introducing a high‐end product before a low‐end product can alleviate cannibalization for a weak entrant. In particular, the profit loss caused by competition is greater than that caused by cannibalization. When competition is intense, firms should consider alleviating the profit loss from competition over cannibalization by introducing a low‐end product before a high‐end product. In that case, the incumbent's high‐end product's quality must be no lower than the entrant's quality but the profit is derived mostly from the mark‐up on the low‐end product. Much of the high‐end product's profit is sacrificed in order to maximize profit from the entire product line. When cannibalization is intense and competition is mild (due to a weak entrant), the incumbent's profit gap between the high‐end and low‐end products is high. In that case, the firm can no longer afford to sacrifice its high‐end products’ profit and the order of introduction reverses.
Packing congruent spheres into a multi‐connected polyhedral domain
Authors: Stoyan Y. , Yaskov G.
Published: June 2012

In this paper, we have considered a problem of packing the maximal number of congruent spheres into a multi‐connected polyhedral domain. A mathematical model of the problem has been formulated on the basis of Φ functions. This paper proposes a special way of constructing starting points. To find local maxima, a modification of the Zoutendijk method of feasible directions and a strategy of active inequalities are used. We developed a special approach to search for an approximation to a global maximum. A number of numerical examples are also provided.
A branch‐and‐price approach to k‐clustering minimum biclique completion problem
Authors: Gualandi Stefano , Maffioli Francesco , Magni Claudio
Published: June 2012

We consider the problem of finding k‐bipartite subgraphs, called “clusters,” in a bipartite graph , such that each vertex i of S appears in exactly one of the subgraphs, every vertex j of T appears in each cluster in which at least one of its neighbors appears, and the total number of edges needed to complete each cluster (i.e. to become a biclique) is minimized. This problem has been shown to be strongly NP‐hard and is known as the k‐clustering minimum biclique completion problem. It has been applied to bundling channels for multicast transmissions. The application consists of finding k‐multicast sessions that partition the set of demands, given a set of demands of services from clients. Each service should belong to a single multicast session, while each client can appear in more than one session. We extend previous work by developing a branch‐and‐price algorithm that embeds a new metaheuristic based on variable neighborhood infeasible search and a branching rule that exploits the problem structure. The metaheuristic can also efficiently solve the pricing subproblem. In addition to the random instances used in the literature, we present structured instances generated using the MovieLens dataset collected by the GroupLens Research Project. Extensive computational results show that our branch‐and‐price algorithm outperforms the approaches proposed in the literature.
Changes in tissue perfusion parameters in dogs with severe sepsis/septic shock in response to goal‐directed hemodynamic optimization at admission to ICU and the relation to outcome
Authors: Conti‐Patara Andreza , de Araújo Caldeira Juliana , de Mattos‐Junior Ewaldo , de Carvalho Haley da Silva , Reinoldes Adriane , Pedron Bruno Gregnanin , Patara Marcelo , Francisco Talib Mariana Semião , Faustino Marcelo , de Oliveira Clair Motos , Cortopassi Silvia Renata Gaido
Published: June 2012

Objective

To evaluate the changes in tissue perfusion parameters in dogs with severe sepsis/septic shock in response to goal‐directed hemodynamic optimization in the ICU and their relation to outcome.

Design

Prospective observational study.

Setting

ICU of a veterinary university medical center.

Animals

Thirty dogs with severe sepsis or septic shock caused by pyometra who underwent surgery and were admitted to the ICU.

Measurements and Main Results

Severe sepsis was defined as the presence of sepsis and sepsis‐induced dysfunction of one or more organs. Septic shock was defined as the presence of severe sepsis plus hypotension not reversed with fluid resuscitation. After the presumptive diagnosis of sepsis secondary to pyometra, blood samples were collected and clinical findings were recorded. Volume resuscitation with 0.9% saline solution and antimicrobial therapy were initiated. Following abdominal ultrasonography and confirmation of increased uterine volume, dogs underwent corrective surgery. After surgery, the animals were admitted to the ICU, where resuscitation was guided by the clinical parameters, central venous oxygen saturation (ScvO2), lactate, and base deficit. Between survivors and nonsurvivors it was observed that the ScvO2, lactate, and base deficit on ICU admission were each related independently to death (P = 0.001,P = 0.030, andP< 0.001, respectively). ScvO2and base deficit were found to be the best discriminators between survivors and nonsurvivors as assessed via receiver operator characteristic curve analysis.

Conclusion

Our study suggests that ScvO2and base deficit are useful in predicting the prognosis of dogs with severe sepsis and septic shock; animals with a higher ScvO2and lower base deficit at admission to the ICU have a lower probability of death.
Selectivity profiling of the novel EP2 receptor antagonist, PF‐04418948, in functional bioassay systems: atypical affinity at the guinea pig EP2 receptor
Authors: Birrell Mark A , Maher Sarah A , Buckley James , Dale Nicole , Bonvini Sara , Raemdonck Kristof , Pullen Nick , Giembycz Mark A , Belvisi Maria G
Published: July 2012

BACKGROUND AND PURPOSE

Understanding the role of the EP2 receptor has been hampered by the lack of a selective antagonist. Recently, a selective EP2 receptor antagonist, PF‐04418948, has been discovered. The aim of this study was to demonstrate the selectivity profile of PF‐04418948 for the EP2 receptor over other EP receptors using a range of isolated tissue systems.

EXPERIMENTAL APPROACH

PF‐04418948 was profiled on a range of isolated tissues to assess its EP receptor potency and selectivity: ONO‐DI‐004‐induced contraction of guinea pig trachea (EP1); ONO‐AE1‐259 and PGE2‐ induced relaxation of mouse and guinea pig trachea (EP2); PGE2‐induced depolarization of guinea pig isolated vagus (EP3); PGE2‐induced relaxation of human and rat trachea (EP4). PF‐04418948 was also profiled in functional murine TP, IP, DP and FP receptor assays.

KEY RESULTS

In bioassay systems, where assessment of potency/selectivity is made against the ‘native’ receptor, PF‐04418948 only acted as an antagonist of EP2 receptor‐mediated events. PF‐04418948 competitively inhibited relaxations of murine and guinea pig trachea induced by ONO‐AE1‐259 and PGE2 respectively. However, the affinity of PF‐04418948 was not equal in the two preparations.

CONCLUSIONS AND IMPLICATIONS

Using a wide range of bioassay systems, we have demonstrated that PF‐04418948 is a selective EP2‐receptor antagonist. Interestingly, an atypically low affinity was found on the guinea pig trachea, questioning its utility as an EP2 receptor assay system. Nevertheless, this compound should be an invaluable tool for investigating the biological activity of PGE2 and the role of EP2 receptors in health and disease.
Mephedrone (4‐methylmethcathinone) and d‐methamphetamine improve visuospatial associative memory, but not spatial working memory, in rhesus macaques
Authors: Wright, Jr MJ , Vandewater SA , Angrish D , Dickerson TJ , Taffe MA
Published: July 2012

BACKGROUND AND PURPOSE

The novel cathinone derivative 4‐methylmethcathinone (4‐MMC; mephedrone) is increasingly popular with recreational users. Little scientific information is available but users report both entactogen‐like and classic stimulant‐like subjective properties. A recent study in humans reported psychomotor speed improvement after intranasal 4‐MMC suggesting classic stimulant properties. Limitations of the user group (which was impaired on some tasks) prompt controlled laboratory investigation.

EXPERIMENTAL APPROACH

Adult male rhesus monkeys were trained to perform tasks from the non‐human primate Cambridge Neuropsychological Test Automated Battery, which assess spatial working memory, visuospatial associative memory, learning and motivation for food reward. Test of bimanual motor coordination and manual tracking were also included. The subjects were challenged with 0.178–0.56 mg·kg−1 4‐MMC and 0.056–0.56 mg·kg−1 d‐methamphetamine (MA), i.m., in randomized order for behavioural evaluation.

KEY RESULTS

A pronounced improvement in visuospatial memory and learning was observed after the 0.32 mg·kg−1 dose of each compound, this effect was confirmed with subsequent repetition of these conditions. Spatial working memory was not improved by either drug, and the progressive ratio, bimanual motor and rotating turntable tasks were all disrupted in a dose‐dependent manner.

CONCLUSIONS AND IMPLICATIONS

These studies show that 4‐MMC produces behavioural effects, including improvements in complex spatial memory and learning that are in large part similar to those of MA in non‐human primates. Thus, the data suggest that the effects of 4‐MMC in monkeys can be classified with classical psychomotor stimulants.
Maternal knowledge of fetal movements in late pregnancy
Authors: Peat Andrea M. , Stacey Tomasina , Cronin Robin , McCowan Lesley M. E.
Published: July 2012

Background

Current evidence suggests that fetal movements are an important indicator of fetal well‐being. About a quarter of women who present with decreased fetal movements have adverse perinatal outcomes such as intrauterine growth restriction and stillbirth. There are no New Zealand studies reporting maternal knowledge about fetal movements in late pregnancy.

Aims

To determine what information women in the third trimester of pregnancy receive about fetal movements, both from their maternity caregivers and from other sources.

Methods

A convenience sample of 100 women attending two antenatal clinics in Auckland in November and December 2011 were interviewed by a medical student.

Results

Ninety‐seven per cent of women reported that their lead maternity carer (LMC) regularly asked about fetal movements, and 62% recalled receiving information from their LMC about what to expect regarding fetal movements in the last three months of pregnancy. Thirty‐three per cent recalled receiving information from their LMC that their baby's movements should increase or stay the same and 20% that their baby's movements may decrease in late pregnancy. Forty per cent were advised to contact their LMC if they had any concerns about their baby's movements, and one‐quarter were informed to seek advice if they had fewer than 10 movements in a day.

Conclusions

Our study suggests a proportion of pregnant women in Auckland do not have optimum information about fetal movements. Strategies to enhance maternal knowledge such as a pamphlet about fetal movements may be helpful.
Use of an Airborne Lidar System to Model Plant Species Composition and Diversity of Mediterranean Oak Forests
Authors: SIMONSON WILLIAM D. , ALLEN HARRIET D. , COOMES DAVID A.
Published: June 2012

Abstract: Airborne lidar is a remote‐sensing tool of increasing importance in ecological and conservation research due to its ability to characterize three‐dimensional vegetation structure. If different aspects of plant species diversity and composition can be related to vegetation structure, landscape‐level assessments of plant communities may be possible. We examined this possibility for Mediterranean oak forests in southern Portugal, which are rich in biological diversity but also threatened. We compared data from a discrete, first‐and‐last return lidar data set collected for 31 plots of cork oak (Quercus suber) and Algerian oak (Quercus canariensis) forest with field data to test whether lidar can be used to predict the vertical structure of vegetation, diversity of plant species, and community type. Lidar‐ and field‐measured structural data were significantly correlated (up to r= 0.85). Diversity of forest species was significantly associated with lidar‐measured vegetation height (R2= 0.50, p < 0.001). Clustering and ordination of the species data pointed to the presence of 2 main forest classes that could be discriminated with an accuracy of 89% on the basis of lidar data. Lidar can be applied widely for mapping of habitat and assessments of habitat condition (e.g., in support of the European Species and Habitats Directive [92/43/EEC]). However, particular attention needs to be paid to issues of survey design: density of lidar points and geospatial accuracy of ground‐truthing and its timing relative to acquisition of lidar data.
Cell Adhesive and Antifouling Polyvinyl Chloride Surfaces Via Wet Chemical Modification
Authors: Gabriel Matthias , Strand Dennis , Vahl Christian‐Friedrich
Published: July 2012

Polyvinyl chloride (PVC) is one of the most frequently used polymers for the manufacturing of medical devices. Limitations for its usage are based upon unfavorable surface properties of the polymer including its hydrophobicity and lack of functionalities in order to increase its versatility. To address this issue, wet chemical modification of PVC was performed through surface amination using the bifunctional compound ethylene diamine. The reaction was conducted in order to achieve maximum surface amination while leaving the bulk material unaffected. The initial activation step was characterized by means of various methods including contact angle measurements, colorimetric amine quantification, infrared spectroscopy, and gel permeation chromatography. Depth profiles were obtained by a confocal microscopic method using fluorescence labeling. Exclusive surface modification was thus confirmed. To demonstrate biological applications of the presented technique, two examples were chosen: The covalent immobilization of the cell adhesive Asp‐Gly‐Asp‐Ser‐peptide (RGD) onto PVC samples yielded a surface that strongly supported cellular adhesion and proliferation of fibroblasts. In contrast, the decoration of PVC with the hydrophilic polymer polyethylene glycol prevented cellular adhesion to a large extent. The impact of these modifications was demonstrated by cell culture experiments.
Mathematical Modeling of Thermal and Circulatory Effects During Hemodialysis
Authors: Droog Rens P.J. , Kingma Boris R.M. , van Marken Lichtenbelt Wouter D. , Kooman Jeroen P. , van der Sande Frank M. , Levin Nathan W. , van Steenhoven Anton A. , Frijns Arjan J.H.
Published: July 2012

Intradialytic hypotension (IDH) is one of the most common complications of hemodialysis (HD) treatment. The initiating factor of IDH is a decrease in blood volume, which is related to an imbalance between ultrafiltration (UF) and refilling rate. Impaired reactivity of resistance and capacitance vessels in reaction to hypovolemia plays possibly a major role in the occurrence of IDH. These vessels also fulfill an important function in body temperature regulation. UF‐induced cutaneous vasoconstriction would result in a reduced surface heat loss and an increase in core temperature. To release body heat, skin blood flow is increased at a later stage of the HD treatment, whereby possibly IDH can occur. The aim of the study is to develop a mathematical model that can provide insight into the impact of thermoregulatory processes on the cardiovascular (CV) system during HD treatment. The mathematical procedure has been created by coupling a thermo‐physiological model with a CV model to study regulation mechanisms in the human body during HD + UF. Model simulations for isothermal versus thermoneutral HD + UF were compared with measurement data of patients on chronic intermittent HD (n = 13). Core temperature during simulated HD + UF sessions increased within the range of measurement data (0.23°C vs. 0.32 ± 0.41°C). The model showed a decline in mean arterial pressure of −7% for thermoneutral HD + UF versus −4% for isothermal HD + UF after 200 min during which relative blood volume changed by −13%. In conclusion, simulation results of the combined model show possibilities for predicting circulatory and thermal responses during HD + UF.
A Controlled Study Evaluating a Novel Surgical Treatment for Kissing Spines in Standing Sedated Horses
Authors: Coomer Richard P. C. , McKane Shaun A. , Smith Naomi , Vandeweerd Jean‐Michel E.
Published: June 2012

Objective

To compare the results of a novel minimally invasive surgical technique with intralesional corticosteroid medication, as treatment for overriding dorsal spinous processes (ORDSP) in horses.

Study Design

Retrospective controlled clinical case series.

Animals

Horses (n = 68) with ORDSP.

Methods

ORDSP was diagnosed based on history, clinical, and radiographic examination. All narrowed spaces were treated. Horses undergoing medical treatment had methylprednisolone acetate injected directly in the affected space under radiographic control. Surgical cases had interspinous ligament desmotomy (ISLD) using Mayo scissors; supraspinous ligaments were left intact. All horses had the same controlled exercise plan and returned to work 3–6 weeks after treatment.

Results

Methylprednisolone was administered in 1–7 spaces in 38 cases, compared with ISLD in 3–8 spaces in 37 cases. Thirty‐four horses (89%) treated medically initially resolved signs of back compared with 35 horses (95%) treated surgically. From these, back pain recurred in 19 medical cases and in none of the surgical cases. Horses having ISLD were 24 times more likely to experience long‐term resolution of signs of back pain (OR 24; 95%CI: 5–115; P = < .0001). Repeat radiographs in 19 surgical cases indicated that interspinous spaces widened significantly postoperatively (P = < .0001).

Conclusions

This surgical technique allowed horses with back pain and radiographic ORDSP to return to work without further clinical signs of back pain and to show radiographic evidence of improvement.