bluuebunny/crossref_metadata_2025 huggingface dataset:
Reviewing the Guayana project: Lifetime migration to and from Bolivar state, Venezuela, 1950–2001
Authors: Ravuri Evelyn D.
Published: August 2011

By the mid‐twentieth century the population and economic resources in many developing economies had become concentrated in the capital city. Planned industrial cities became an important mechanism to encourage more balanced urban systems as well as development in peripheralized regions. Venezuela boasts one of the most impressive planned industrial cities, Ciudad Guayana, constructed in 1959 in the resource rich but inaccessible Bolivar state in the southeast. This paper summarizes the lifetime migration to and from Bolivar state for the years 1950, 1971 and 2001. Whereas the majority of lifetime migrants originated from the neighbouring northeast region in 1950 and 1971, by 2001 more migrants arrived from the capital region. For lifetime outmigrants, the destination states became more diverse and less focused on the capital region. Gender ratios of lifetime migrants to and from Bolivar became more equitable as women became more prominent in migration flows. The level of urban primacy in Venezuela declined substantially after 1971 as the country became more internally integrated, although this more equitable distribution of the country's population may not have been solely a result of the creation of the growth pole, but a result of wider economic development.
Human geography in higher education in Malaysia: Issues and challenges
Authors: Buang Amriah
Published: August 2011

This paper reviews the state of higher education human geography in contemporary Malaysia in relation to four main challenges: defending the unity of identity of higher education geography as a coherent and distinct discipline; ensuring the institutional survival of geography in higher education; enhancing the visibility of geographers as public intellectuals; and fostering the internationalization of human geography in Malaysia. It also suggests possible measures in responding to these. Moreover, while sharing the problems of developing higher education human geography experienced in other countries, Malaysia suffers most from national education policies that place lesser importance on the teaching of geography in schools, that stipulate a non‐English (Malay) medium of instruction, and that have been late in espousing an outward looking research university concept. In summing up the prevailing conditions as depicting a mixed bag of benign contentment, hard‐nosed pragmatism and continuing frustrations, it is uncertain whether recent policy changes to advance research environments in public universities can appreciably alleviate the fourfold challenges mentioned above.
Clinical and prognostic reports from 270 patients with multiple primary melanomas: a 34‐year single‐institution study
Authors: Savoia P. , Osella‐Abate S. , Deboli T. , Marenco F. , Stroppiana E. , Novelli M. , Fierro M.T. , Bernengo M.G.
Published: August 2011

Background  Development of more than one primary melanoma in a sole patient is frequent, accounting for 1.2–8.2% of melanoma patients in most recent series.

Objective and methods  Clinical, histological and epidemiological characteristics of 270 multiple primary melanomas patients were reviewed.

Results  Two‐hundred and seven patients (76.7%) had two melanomas, whereas in the remaining 63 the number of primary ranged from three to eight; on the whole, 639 multiple primary melanomas were identified. Synchronous melanomas developed more frequently in patients with three or more lesions; median age was significantly lower in the group of patients with more than three melanomas than in the others. Mean Breslow’s thickness significantly decreases (P < 0.001) from the first (1.77 ± 1.76 mm) to subsequent primaries (0.85 ± 1.25 mm for the second and 0.66 ± 0.48 mm for the third melanoma). Percentage of ‘in situ’ melanomas was 5.6% as first diagnosis, but increased to 24.8% for the second melanoma; number of nodular melanomas was significantly lower for succeeding diagnosis. AJCC stage at diagnosis showed a statistical prognostic significance, whereas outcome and survival did not depend on the number of primary lesions. Multivariate analysis confirmed the prognostic role of Breslow’s thickness, ulceration, gender and patient age, and the better prognosis of patients with multiple melanomas, respect to those with single primary melanoma.

Conclusions  Skin examination and long‐term follow‐up are mandatory for patients affected by melanoma, with the intent to promptly diagnose not only a disease progression but also possible new primary melanomas.
Fundamental Information in Technical Trading Strategies
Authors: Bonenkamp Ute , Homburg Carsten , Kempf Alexander
Published: August 2011

Abstract:  Technical trading strategies assume that past price trends predict future ones. Their application may be profitable if the past trend reflects fundamental information that has not yet been fully priced. However, if the trend merely reflects temporary pricing pressures, technical trading will presumably fail. We argue that using financial statements as an additional source of information helps to avoid such failure. We implement a trading strategy that uses operating cash flows to identify enduring past price upturns. This strategy outperforms a purely technical momentum strategy, seems to be practicable, and its profits exceed transactions costs.
The predictive value of low heart rate and heart rate variability during stress for reoffending in delinquent male adolescents
Authors: De Vries‐Bouw Marjan , Popma Arne , Vermeiren Robert , Doreleijers Theo A. H. , Van De Ven Peter M. , Jansen Lucres M. C.
Published: August 2011

Low autonomic (re)activity is a consistent correlate of antisocial behavior in juveniles. However, longitudinal research relating autonomic measures to persistent antisocial behavior has remained scarce. Therefore, in the present study we examined the predictive value of heart rate (HR) and heart rate variability (HRV, often studied as respiratory sinus arrhythmia) for reoffending in delinquent male adolescents. At initial assessment, HR and HRV were measured at rest and in response to a public speaking task. Registered reoffending was assessed after 5‐year follow‐up. Attenuated HR response and stronger HRV response to stress predicted higher reoffending rates. Results provide evidence that HR/HRV reactivity are neurobiological markers for persistent juvenile antisocial behavior. Although effect sizes were small to moderate, our findings underscore the consistency of the relationship between autonomic markers and antisocial behavior.
Factors that influence the consumption of food outside the home in Brazil
Authors: de Rezende Daniel Carvalho , de Avelar Ana Elisa Stacanelli
Published: August 2011

The food sector has taken on an unprecedented dynamism in recent years. The processing and distribution of food, although heavily influenced by tradition, have seen intensive innovations, leading to changes in the way individuals consume. One of these changes is the consistent growth of the habit of eating outside the home. Consuming food outside the home involves a number of practices such as eating at commercial establishments that specialize in food (restaurants, fast food restaurants and snack bars) and those that offer food as a part of their services (hotels, in‐flight meals), and non‐commercial alternatives such as the homes of family and friends. In order to describe the eating habits of consumers in the town of Lavras in Minas Gerais State, Brazil, especially when it comes to eating outside the home, a quantitative study was conducted, with 413 questionnaires being distributed by convenience sampling. Among the main results are: (a) a search for variety as a motivator for eating outside the home; (b) convenience as an important element on many occasions of consumption; (c) more intensive consumption and more favourable attitudes towards eating out on the part of younger people, people with higher incomes, no children and a higher degree of schooling; (d) importance of paying for food by the kilo. When compared with a study conducted in England, important similarities were identified in socio‐demographic influences, although the cultural factors are notable when it comes to dishes and the types of eating establishment. The growing habit of eating out has therefore become a worldwide phenomenon, but with cultural and regional differences that have led to different rhythms in terms of change and the way food is supplied. The recovery of embedded cultural habits, with increased value being given to slow food, traditional dishes and tradition itself, appears to co‐exist with a productivity model of food courts, pasteurization and accessible prices. The occasion for consumption, which may be understood as the dichotomies of ‘weekday versus weekend’ or ‘convenience versus leisure’, is an important element that influences consumer behaviours. The undertaking of a cross‐cultural comparative study can be seen as an important step in this field of research.
Formulation optimisation of a whey lemon beverage using a blend of the sweeteners aspartame and saccharin
Authors: MEENA MUKESH K , ARORA SUMIT , SHENDURSE ASHISH M , SHARMA VIVEK , WADHWA BALBIR KAUR , SINGH ASHISH K
Published: August 2011

Product formulations based on combinations of two sweeteners were optimised in a sweetened paneer whey lemon beverage (WLB) by organoleptic panels. The binary sweetener blend aspartame/saccharin (70:30, 0.0425%) scored the highest based upon comparison with the best‐optimised single sweetener aspartame (0.07%) in WLB and had nonsignificant differences with the control WLB sweetened with sucrose in all sensory attributes. This best binary blend showed maximum synergy in sweetness intensity (14.4%) and overall acceptability (7.5%) in respect of a single sweetener aspartame. The multiple‐sweetener approach involving use of binary blend (0.0425%) resulted in 39% reduction of usage level when compared with single sweetener aspartame (0.07%).
Decreased α4β2 nicotinic receptor number in the absence of mRNA changes suggests post‐transcriptional regulation in the spontaneously hypertensive rat model of ADHD
Authors: Wigestrand Mattis B. , Mineur Yann S. , Heath Christopher J. , Fonnum Frode , Picciotto Marina R. , Walaas Sven Ivar
Published: August 2011

J. Neurochem. (2011) 119, 240–250.

The spontaneously hypertensive rat (SHR) is widely used as a model of attention‐deficit/hyperactivity disorder (ADHD). Deficits in central nicotinic receptors (nAChRs) have been previously observed in SHRs, which is interesting since epidemiological studies have identified an association between smoking and ADHD symptoms in humans. Here, we examine whether nAChR deficits in SHRs compared with Wistar Kyoto rat (WKY) controls are nAChR subtype‐specific and whether these deficits correlate with changes at the level of mRNA transcription in specific brain regions. Levels of binding sites (Bmax) and dissociation constants (Kd) for nAChRs were determined from saturation curves of high‐affinity [3H]epibatidine‐ and [3H] Methyllycaconitine (MLA) binding to membranes from cortex, striatum, hippocampus and cerebellum. In additional brain regions, nAChRs were examined by autoradiography with [125I]A‐85380 and [125I]α‐bungarotoxin. Levels of mRNA encoding nAChR subunits were measured using quantitative real‐time PCR (qPCR). We showed that the number of α4β2 nAChR binding sites is lower globally in the SHR brain compared with WKY in the absence of significant differences in mRNA levels, with the exception of lower α4 mRNA in cerebellum of SHR compared with WKY. Furthermore, nAChR deficits were subtype‐ specific because no strain difference was found in α7 nAChR binding or α7 mRNA levels. Our results suggest that the lower α4β2 nAChR number in SHR compared with WKY may be a consequence of dysfunctional post‐transcriptional regulation of nAChRs.
Adoption, use and perception of Australian acacias around the world
Authors: Kull Christian A. , Shackleton Charlie M. , Cunningham Peter J. , Ducatillon Catherine , Dufour‐Dror Jean‐Marc , Esler Karen J. , Friday James B. , Gouveia António C. , Griffin A. R. , Marchante Elizabete , Midgley Stephen J. , Pauchard Aníbal , Rangan Haripriya , Richardson David M. , Rinaudo Tony , Tassin Jacques , Urgenson Lauren S. , von Maltitz Graham P. , Zenni Rafael D. , Zylstra Matthew J.
Published: August 2011

Aim  To examine the different uses and perceptions of introduced Australian acacias (wattles; Acacia subgenus Phyllodineae) by rural households and communities.

Location  Eighteen landscape‐scale case studies around the world, in Vietnam, India, Réunion, Madagascar, South Africa, Congo, Niger, Ethiopia, Israel, France, Portugal, Brazil, Chile, Dominican Republic and Hawai‘i.

Methods  Qualitative comparison of case studies, based on questionnaire sent to network of acacia researchers. Information based on individual knowledge of local experts, published and unpublished sources.

Results  We propose a conceptual model to explain current uses and perceptions of introduced acacias. It highlights historically and geographically contingent processes, including economic development, environmental discourses, political context, and local or regional needs. Four main groupings of case studies were united by similar patterns: (1) poor communities benefiting from targeted agroforestry projects; (2) places where residents, generally poor, take advantage of a valuable resource already present in their landscape via plantation and/or invasion; (3) regions of small and mid‐scale tree farmers participating in the forestry industry; and (4) a number of high‐income communities dealing with the legacies of former or niche use of introduced acacia in a context of increased concern over biodiversity and ecosystem services.

Main conclusions  Economic conditions play a key role shaping acacia use. Poorer communities rely strongly on acacias (often in, or escaped from, formal plantations) for household needs and, sometimes, for income. Middle‐income regions more typically host private farm investments in acacia woodlots for commercialization. Efforts at control of invasive acacias must take care to not adversely impact poor dependent communities.
Phylogeographic consequences of different introduction histories of invasive Australian Acacia species and Paraserianthes lophantha (Fabaceae) in South Africa
Authors: Le Roux Johannes J. , Brown Gillian K. , Byrne Margaret , Ndlovu Joice , Richardson David M. , Thompson Genevieve D. , Wilson John R. U.
Published: August 2011

Aim  The genetic makeup and evolutionary potential of alien species can be profoundly influenced by their introduction history, but without detailed historical records, it can be difficult to ascertain the strength of this historical contingency. We explore how the known introduction histories combined with phylogeographic patterns in the native range have affected the genetic diversity in the invasive range for five Australian trees introduced to South Africa (Acacia cyclops, Acacia mearnsii, Acacia pycnantha, Acacia saligna and Paraserianthes lophantha).

Location  Western Australia, South Australia, Victoria and New South Wales (native and invasive ranges), and South Africa and the Hawaiian Islands (invasive range).

Methods  DNA sequence data were generated for all study species for either the external transcribed spacer (ETS) or plastid rpl32‐trnL(UAG) gene regions (combined total of 180 DNA sequences). Using statistical parsimony networks and genetic diversity indices, we compared genetic structure and variation in native and invasive ranges.

Results  Australian acacia species tend to have high genetic diversity at the population level in their native ranges, often showing high intra‐specific divergence. In most instances, these species have similar levels of population genetic diversity in their adventive ranges in South Africa, but lack structure. For A. cyclops, A. saligna and P. lophantha, we found evidence for intra‐specific hybridization between mixed genetic entities in the invasive range, arguably as a result of the structured native range being broadly sampled prior to introduction.

Main conclusions  Invasive species that have been extensively used in forestry often have complex introduction histories resulting in equally complex genetic signatures in the invasive range. Our results show that extreme caution should be taken when using indirect inferences (molecular genetic data) of introduction histories in the absence of detailed introduction records.
Insect pests and pathogens of Australian acacias grown as non‐natives – an experiment in biogeography with far‐reaching consequences
Authors: Wingfield Michael J. , Roux Jolanda , Wingfield Brenda D.
Published: August 2011

Aims  To highlight the increasing importance of pests and pathogens to Australian Acacia species, where they are planted as non‐natives in commercial plantations and in their native environment.

Location  Africa, Asia, Australia, South America.

Methods  Existing literature and results of unpublished surveys on pests and pathogens of Australian acacias are reviewed. These are discussed within the context of a growing importance of invasive alien insects and pathogens including novel encounters and host jumps.

Results  Australian acacias planted as non‐natives in various parts of the world are increasingly threatened by pests and pathogens. These include those that are accidentally being introduced into the new environments as well as ‘new encounter’ pests and pathogens that are undergoing host shifts to infect non‐native acacias. Furthermore, insects and pathogens for biological control of invasive Australian acacias present substantial challenges for plantation forestry.

Main conclusions  Pests and pathogens will seriously challenge plantation forestry based on non‐native Australian acacias. In the longer term, new encounter pests and pathogens will also threaten these trees in their native environments.
Invasiveness in introduced Australian acacias: the role of species traits and genome size
Authors: Gallagher Rachael V. , Leishman Michelle R. , Miller Joseph T. , Hui Cang , Richardson David M. , Suda Jan , Trávníček Pavel
Published: August 2011

Aim To assess associations between invasiveness, genome size and species traits in AustralianAcaciaspecies introduced outside their native range.

Location Global.

Methods Holoploid genome size was determined by flow cytometry for 92 species inAcaciasubgenusPhyllodineaenative to Australia. These data were used to test whether genome size was significantly different for invasive (n = 21; species known to be established and spreading in foreign environments) and non‐invasive (n = 71; species that have been introduced to foreign environments but which are not known to be spreading) species. Data for five functional traits [seed mass, specific leaf area (SLA), relative growth rate (RGR), maximum height and dispersal mode] and three characteristics of native range (size, temperature range and precipitation range) were used to test for univariate and multivariate relationships between (1) invasiveness and traits and (2) genome size and traits.

Results Genome size ranged from 1.20 to 2.13 pg/2C and was not significantly smaller in invasive compared with non‐invasive acacias. However, invasive acacias were found to be taller and possess a larger native range size and a wider range of annual precipitation when compared with non‐invasive acacias. Multivariate analyses revealed significant differences between invasive and non‐invasive acacias (PERMANOVA;P < 0.01) driven largely by differences in native range characteristics. We detected a positive relationship between genome size and SLA (P = 0.02) and elaiosome dispersal mode (P < 0.01) in analyses across species, but these findings were not supported by evolutionary divergence analyses.

Main conclusions Genome size variation does not underpin variation in traits associated with the invasive/non‐invasive dichotomy in introduced acacias, probably because of the very small DNA values in theAcaciaspecies studied. Acacias introduced into new environments are most likely to become invasive if they are tall shrubs or trees and are widely distributed in their native range.
Modelling horses for novel climate courses: insights from projecting potential distributions of native and alien Australian acacias with correlative and mechanistic models
Authors: Webber Bruce L. , Yates Colin J. , Le Maitre David C. , Scott John K. , Kriticos Darren J. , Ota Noboru , McNeill Asha , Le Roux Johannes J. , Midgley Guy F.
Published: August 2011

Aim  Investigate the relative abilities of different bioclimatic models and data sets to project species ranges in novel environments utilizing the natural experiment in biogeography provided by Australian Acacia species.

Location  Australia, South Africa.

Methods  We built bioclimatic models for Acacia cyclops and Acacia pycnantha using two discriminatory correlative models (MaxEnt and Boosted Regression Trees) and a mechanistic niche model (CLIMEX). We fitted models using two training data sets: native‐range data only (‘restricted’) and all available global data excluding South Africa (‘full’). We compared the ability of these techniques to project suitable climate for independent records of the species in South Africa. In addition, we assessed the global potential distributions of the species to projected climate change.

Results  All model projections assessed against their training data, the South African data and globally were statistically significant. In South Africa and globally, the additional information contained in the full data set generally improved model sensitivity, but at the expense of increased modelled prevalence, particularly in extrapolation areas for the correlative models. All models projected some climatically suitable areas in South Africa not currently occupied by the species. At the global scale, widespread and biologically unrealistic projections by the correlative models were explained by open‐ended response curves, a problem which was not always addressed by broader background climate space or by the extra information in the full data set. In contrast, the global projections for CLIMEX were more conservative. Projections into 2070 indicated a polewards shift in climate suitability and a decrease in model interpolation area.

Main conclusions  Our results highlight the importance of carefully interpreting model projections in novel climates, particularly for correlative models. Much work is required to ensure bioclimatic models performed in a robust and ecologically plausible manner in novel climates. We explore reasons for variations between models and suggest methods and techniques for future improvements.
Global uses of Australian acacias – recent trends and future prospects
Authors: Griffin A. R. , Midgley S. J. , Bush D. , Cunningham P. J. , Rinaudo A. T.
Published: August 2011

Aim This study reports on the contribution of the Australian Tree Seed Centre (ATSC) to the international dissemination of Australian acacias. It also describes the current uses and the scale of economic benefits derived from planting Australian acacias, and speculates about possible future trends in usage. This information is crucial for the evaluation of overall human‐mediated transfers of Australian acacias as a global experiment in biogeography.

Location Australia and Global.

Methods ATSC databases were used to determine which taxa were sent to which regions of the world and in what numbers. Location, scale and value of uses of the most important species were described from a review of published and grey literature, and we drew on our collective experience to speculate about future trends.

Results The ATSC despatched samples of 322 taxa (or roughly a third ofAcaciaspecies native to Australia) between 1980 and 2010 to 149 countries. Plantations in SE Asia and South Africa supplying the pulp and paper industry cover an area of over 2 M ha and produce pulp worth around $US4.3B p.a. In SE Asia, pulpwood species also provide logs for an expanding industry based on solid wood product. Tannin is produced fromAcacia mearnsiiin South Africa and Brazil. A suite of multi‐purpose species helps meeting the demand for food, fodder, fuelwood, poles and site amelioration in dry zone regions of Africa and elsewhere and are widely incorporated into agro‐forestry systems.Acacia salignais the most widely planted non‐timber species with around 600,000 ha established worldwide. Many acacia species also have horticultural uses particularly in Europe.

Main conclusions The ATSC has been the major agent for systematic exploration and worldwide dissemination of Australian acacias over the past 30 years, but seed from local and regional sources of exploited species will dominate future movements. The scale of production from currently planted species will expand to meet the demands of population growth, using improved varieties. Plantations for energy and carbon sequestration might become increasingly widespread.
Risk assessment, eradication, and biological control: global efforts to limit Australian acacia invasions
Authors: Wilson John R. U. , Gairifo Carla , Gibson Michelle R. , Arianoutsou Margarita , Bakar Baki B. , Baret Stéphane , Celesti‐Grapow Laura , DiTomaso Joseph M. , Dufour‐Dror Jean‐Marc , Kueffer Christoph , Kull Christian A. , Hoffmann John H. , Impson Fiona A. C. , Loope Lloyd L. , Marchante Elizabete , Marchante Hélia , Moore Joslin L. , Murphy Daniel J. , Tassin Jacques , Witt Arne , Zenni Rafael D. , Richardson David M.
Published: August 2011

Aim  Many Australian Acacia species have been planted around the world, some are highly valued, some are invasive, and some are both highly valued and invasive. We review global efforts to minimize the risk and limit the impact of invasions in this widely used plant group.

Location  Global.

Methods  Using information from literature sources, knowledge and experience of the authors, and the responses from a questionnaire sent to experts around the world, we reviewed: (1) a generalized life cycle of Australian acacias and how to control each life stage, (2) different management approaches and (3) what is required to help limit or prevent invasions.

Results  Relatively few Australian acacias have been introduced in large numbers, but all species with a long and extensive history of planting have become invasive somewhere. Australian acacias, as a group, have a high risk of becoming invasive and causing significant impacts as determined by existing assessment schemes. Moreover, in most situations, long‐lived seed banks mean it is very difficult to control established infestations. Control has focused almost exclusively on widespread invaders, and eradication has rarely been attempted. Classical biological control is being used in South Africa with increasing success.

Main conclusions  A greater emphasis on pro‐active rather than reactive management is required given the difficulties managing established invasions of Australian acacias. Adverse effects of proposed new introductions can be minimized by conducting detailed risk assessments in advance, planning for on‐going monitoring and management, and ensuring resources are in place for long‐term mitigation. Benign alternatives (e.g. sterile hybrids) could be developed to replace existing utilized taxa. Eradication should be set as a management goal more often to reduce the invasion debt. Introducing classical biological control agents that have a successful track‐record in South Africa to other regions and identifying new agents (notably vegetative feeders) can help mitigate existing widespread invasions. Trans‐boundary sharing of information will assist efforts to limit future invasions, in particular, management strategies need to be better evaluated, monitored, published and publicised so that global best‐practice procedures can be developed.
Impacts of invasive Australian acacias: implications for management and restoration
Authors: Le Maitre David C. , Gaertner Mirijam , Marchante Elizabete , Ens Emilie‐Jane , Holmes Patricia M. , Pauchard Aníbal , O’Farrell Patrick J. , Rogers Andrew M. , Blanchard Ryan , Blignaut James , Richardson David M.
Published: August 2011

Aim  The biophysical impacts of invasive Australian acacias and their effects on ecosystem services are explored and used to develop a framework for improved restoration practices.

Location  South Africa, Portugal and Chile.

Methods  A conceptual model of ecosystem responses to the increasing severity (density and duration) of invasions was developed from the literature and our knowledge of how these impacts affect options for restoration. Case studies are used to identify similarities and differences between three regions severely affected by invasions of Australian acacias: Acacia dealbata in Chile, Acacia longifolia in Portugal and Acacia saligna in South Africa.

Results  Australian acacias have a wide range of impacts on ecosystems that increase with time and disturbance, transform ecosystems and alter and reduce ecosystem service delivery. A shared trait is the accumulation of massive seed banks, which enables them to become dominant after disturbances. Ecosystem trajectories and recovery potential suggest that there are important thresholds in ecosystem state and resilience. When these are crossed, options for restoration are radically altered; in many cases, autogenic (self‐driven and self‐sustaining) recovery to a pre‐invasion condition is inhibited, necessitating active intervention to restore composition and function.

Main conclusions  The conceptual model demonstrates the degree, nature and reversibility of ecosystem degradation and identifies key actions needed to restore ecosystems to desired states. Control and restoration operations, particularly active restoration, require substantial short‐ to medium‐term investments, which can reduce losses of biodiversity and ecosystem services, and the costs to society in the long term. Increasing restoration effectiveness will require further research into linkages between impacts and restoration. This research should involve scientists, practitioners and managers engaged in invasive plant control and restoration programmes, together with society as both the investors in, and beneficiaries of, more effective restoration.
Predicting the subspecific identity of invasive species using distribution models: Acacia saligna as an example
Authors: Thompson Genevieve D. , Robertson Mark P. , Webber Bruce L. , Richardson David M. , Le Roux Johannes J. , Wilson John R. U.
Published: August 2011

Aim  To explore whether the subspecific genetic entities of Acacia saligna occupy different bioclimatic niches in their native and introduced ranges and whether these niches are predictable using species distribution models (SDMs).

Location  Australia, South Africa and the Mediterranean Basin.

Methods  Species distribution models were developed in MAXENT using six climatic variables to calculate the climatic suitability of the ranges of A. saligna. We assessed (1) the subspecific niche differences identified by SDMs using measures of niche overlap and model performance; (2) the ability of SDMs to predict the most likely subspecific genetic entities present in South Africa based on comparisons to genetic data; and (3) the ability of SDMs to predict the most likely subspecific genetic entities present in the Mediterranean Basin. All model projections were assessed for sensitivity and modelled prevalence as indicators of model fit and predictability.

Results  The SDMs identified different subspecific bioclimatic niches in the native range. Sensitivity and modelled prevalence show that none of the models correctly predicted the full range of A. saligna in South Africa or the Mediterranean Basin. Models also show that the South African niche is different to that in the native range.

Main conclusions  Subspecies of A. saligna occupy quantifiably distinct bioclimatic niches in their native ranges, implying that they should occupy distinct niches in their invasive ranges. However, projections to the introduced range did not correspond with known occurrences. Our SDMs are unable to predict the full introduced niche of A. saligna at a species or subspecies level in either South Africa or the Mediterranean Basin. Range limits in the native and introduced ranges may be determined by additional factors not used in the SDMs developed in this study.
Captopril and telmisartan treatments attenuate cadmium‐induced testicular toxicity in rats
Authors: Fouad Amr A. , Jresat Iyad
Published: August 2011

The possible protective effect of captopril, an angiotensin‐converting enzyme inhibitor, vs. telmisartan, an angiotensin II‐receptor antagonist, was investigated in rats with testicular injury induced by a single i.p. injection of cadmium chloride (2 mg/kg). Captopril (60 mg/kg/day, p.o.) and telmisartan (10 mg/kg/day, p.o.) were given for five consecutive days, starting 3 days before cadmium administration. Both agents significantly increased serum testosterone level, which was reduced by cadmium, suppressed lipid peroxidation, restored the depleted reduced glutathione, decreased the elevations of nitric oxide, tumor necrosis factor‐α, and cadmium ion levels, and attenuated the reductions of selenium and zinc ions in testicular tissue resulted from cadmium administration. Immunohistochemical analysis revealed that both captopril and telmisartan significantly reduced the cadmium‐induced expression of inducible nitric oxide synthase, nuclear factor‐κB, Fas ligand, and caspase‐3 in testicular tissue. The differences between the results obtained with captopril and telmisartan were insignificant, suggesting that both drugs equally protected the testicular tissue from the detrimental effects of cadmium.
Biliary atresia with associated structural malformations in Canadian infants
Authors: Guttman Orlee R. , Roberts Eve A. , Schreiber Richard A. , Barker Collin C. , Ng Vicky L. ,   the Canadian Pediatric Hepatology Research Group
Published: August 2011

Background: Biliary atresia (BA) is associated with extrahepatic congenital malformations in a minority of affected infants. The term commonly applied to this subgroup is ‘BASM’ for biliary atresia splenic malformation syndrome, as spleen abnormalities are prominent.

Aims and methods: To examine clinical outcome in Canadian BA patients with extrahepatic congenital malformations in the Canada‐wide BA database of patients born between 1985 and 2002, and additionally, to recharacterized the syndrome. Patients had ≥1 of the following: a/polysplenia, abnormal abdominal situs, intestinal malrotation, abdominal vascular anomaly or congenital heart disease.

Results: Among 328 BA patients, 44 (13%) had associated congenital abnormalities. Intra‐abdominal anomalies included polysplenia (n=25), abnormal abdominal situs (n=9), intestinal malrotation (n=19), portal vein anomaly (n=12), hepatic artery anomaly (n=3) and inferior vena cava interruption (n=20). Twenty‐six patients had cardiac malformations including pulmonary stenosis (n=11), ventricular septal defect (n=10), atrial septal defect (n=7), total anomalous pulmonary venous return (n=3), double outlet right ventricle (n=3), tetralogy of Fallot (n=2), atrioventricular canal (n=2), dextrocardia (n=2), bicuspid aortic valve (n=2), hypoplastic left heart (n=1) and partial anomalous pulmonary venous return (n=1). Age at Kasai operation, performance of liver transplant, overall survival, post‐Kasai native liver survival and transplant survival were comparable to isolated BA. Presence of polysplenia or complex cardiac disease did not reduce post‐Kasai native liver survival. Three patients had ≥2 typical abnormalities without polysplenia: thus, splenic malformations are not essential to this BA subgroup. Hierarchical cluster analysis demonstrated characteristic abnormalities grouped in a multiplicity of combinations, consistent with a spectrum of defective lateralization.

Conclusion: We suggest that the acronym ‘BASM’ be redefined as ‘biliary atresia structural malformation’.
Extracorporeal artificial liver support in hypoxic liver injury
Authors: Drolz Andreas , Saxa Reinhard , Scherzer Thomas , Fuhrmann Valentin
Published: August 2011

The incidence of hypoxic liver injury, most commonly referred to as hypoxic hepatitis (HH), is up to 10% in critically ill patients. In the majority of cases, HH occurs as a consequence of haemodynamic impairment following cardiogenic or septic shock. A marked, dramatic increase in the aminotransferase levels in a setting of cardiocirculatory failure is the key characteristic of HH. HH may contribute to several complications such as hepatopulmonary syndrome and hypoglycaemia. The overall mortality after the onset of HH is approximately 50–60% within 1 month. We report a case of severe HH that was successfully bridged using the Molecular Adsorbent Recirculating System. In addition to the possible effects of extracorporeal liver support devices, the recognition of HH and therapy of the underlying disease that led to the occurrence of HH is of central importance.
The clinical challenges of acute on chronic liver failure
Authors: Graziadei Ivo W.
Published: August 2011

Acute on chronic liver failure (ACLF) encompasses patients with previously well‐compensated liver disease in whom an acute decompensation of liver function occurs because of a precipitating event. There are emerging data on the presentation and course of patients with this profile of liver disease; a clear definition based on precise diagnostic criteria, however, remains difficult to establish. In a high percentage of patients, ACLF is associated with the development of multi‐organ failure leading to high in‐hospital mortality despite costly intensive care therapy. Liver transplantation remains the only curative therapeutic option for the majority of these patients. Therefore, early identification of the precipitating events inducing ACLF and better understanding of the underlying mechanism are key issues for the prevention and treatment of ACLF. However, although there is increasing evidence that cytokines play a major role in the development of ACLF, the pathophysiology remains complex and poorly understood.
Detoxification as a treatment goal in hepatic failure
Authors: Kramer Ludwig , Kodras Katharina
Published: August 2011

Acute liver failure (ALF) is a dramatic clinical syndrome with high mortality because of cerebral oedema (type A hepatic encephalopathy) and multi‐organ failure. With intensive care medicine and emergent liver transplantation being the mainstay of treatment, alternatives to transplantation are increasingly needed. Ammonia has been recognised as a major toxin in patients with ALF. It can be effectively removed by haemodialysis, haemofiltration and artificial liver support (a combination of extracorporeal toxin absorption and haemodialysis). Previous studies of extracorporeal detoxification, however, have either not specifically targeted ammonia or were hampered by poor biocompatibility and obsolete pathophysiological assumptions, ultimately failing to improve the prognosis. Moreover, most patients were treated only late after the emergence of advanced HE and multi‐organ failure, while detoxification should prevent these complications. Acute‐on‐chronic liver failure (AOCLF) occurs in the setting of chronic liver disease and has an equally poor prognosis. Here, the goals of extracorporeal blood detoxification are renal support and haemodynamic stabilisation in order to support recompensation. Patients with AOCLF, unfortunately, are at a risk for treatment‐related complications including bleeding, thrombocytopenia, hypotension and acute renal failure, making biocompatibility a critical issue. Peritoneal dialysis could possibly emerge as a more biocompatible way of treating refractory hepatorenal syndrome. This article will critically analyse the pathophysiological concepts and goals of extracorporeal detoxification in acute and chronic liver diseases.
Clearing of toxic substances: are there differences between the available liver support devices?
Authors: Krisper Peter , Stadlbauer Vanessa , Stauber Rudolf E.
Published: August 2011

Toxins accumulating in liver failure split into water solved (e.g. ammonia) and albumin bound substances (e.g. bilirubin). Because the latter cannot be removed by conventional haemodialysis, special liver support systems have been developed. The majority of data concerning elimination efficiency exist for the cell‐free devices Molecular Adsorbent Recirculating System (MARS) and Prometheus, as they have been commercially available in Europe since many years. Overall, Prometheus provides higher clearances for most liver toxins, especially if they are tightly albumin bound. However, for bile acids and cytokines no such differences could be found. Single pass albumin dialysis (SPAD) can be assumed to be equally effective as MARS. None of the bioartificial liver support systems being developed is on the market today and published clearance data are scarce. In general, clearance efficiency for albumin bound substances is relatively low in all systems currently available. Besides optimizing biocompatibility and selectivity, future technologies should also focus on improved detoxification efficiency of liver support devices.
Albumin dialysis: current practice and future options
Authors: Wauters Joost , Wilmer Alexander
Published: August 2011

The current management of patients with severe liver failure encompasses treatment of the precipitating event and supportive therapy for extra‐hepatic end‐organ dysfunction while waiting for the liver to recover or for a suitable graft to become available. Molecular Adsorbent Recirculating System (MARS) is an extracorporeal detoxification device that allows the save and effective removal of albumin‐bound as well as water‐soluble substances in an effort to overcome phases of critical organ dysfunction or to bridge patients until transplantation. MARS has proven to be a useful treatment in patients with acute‐on‐chronic liver failure and acute liver failure for improving biochemical parameters and clinical symptoms but benefits in patient outcome have not yet been fully demonstrated. The optimal timing for initiation, frequency and duration of MARS treatment, and the biochemical and clinical parameters on which to base clinical decisions, remain partially unanswered issues.
NADPH oxidase‐mediated platelet isoprostane over‐production in cirrhotic patients: implication for platelet activation
Authors: Basili Stefania , Raparelli Valeria , Riggio Oliviero , Merli Manuela , Carnevale Roberto , Angelico Francesco , Tellan Guglielmo , Pignatelli Pasquale , Violi Francesco ,   CALC Group
Published: August 2011

Background:

In patients with cirrhosis conflicting findings, inherent to platelet function and its clinical implication, are still matters of discussion. Cirrhosis is characterized by enhanced production of isoprostanes, index of oxidative stress in vivo, that is known to stem from nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2)‐generating oxidative stress and elicit platelet activation.

Aim:

To analyse the relationship between oxidative stress and platelet activation in cirrhosis.

Methods:

A cross‐sectional study including 51 cirrhotic patients and sex‐ and age‐matched control patients has been designed. Soluble NOX2‐derived peptide (sNOX2‐dp), a direct marker of NADPH oxidase activation, isoprostanes urinary excretion, platelet isoprostanes and two markers of in vivo platelet activation, i.e. soluble CD40 Ligand (sCD40L) and soluble P‐selectin (sPs), were measured.

Results:

Compared with controls, cirrhotic patients had higher levels of sPs (P = 0.034), sCD40L (P < 0.0001), sNOX2‐dp (P = 0.0016), urinary excretion of isoprostanes (P < 0.0001) and arachidonic acid‐induced platelet isoprostane formation (P < 0.0001). A significant correlation between sNOX2‐dp and platelet (Rs = 0.39, P = 0.0051) and urinary (Rs = 0.67, P < 0.0001) isoprostanes was detected; also, sNOX2‐dp and isoprostanes significantly correlated with sPs and sCD40L. A stepwise regression analysis revealed that sNOX2‐dp was independently related to sCD40L plasma levels.

Conclusions:

This study provides evidence that in cirrhosis, platelet isoprostanes are over‐produced and could be implicated in platelet activation.
Risk factors for prolonged stay in cardiac surgery intensive care units
Authors: Giakoumidakis Konstantinos , Baltopoulos George I. , Charitos Christos , Patelarou Evridiki , Galanis Petros , Brokalaki Hero
Published: August 2011

Aims and objectives: To identify the factors that might affect the length of stay in the intensive care unit (ICU‐LOS) among cardiac surgery patients.

Background: ICU‐LOS forms an important factor for assessing the effectiveness of the provided nursing care. A number of factors can be accused for increasing patient hospitalization. The nursing workload (NWL), among others, was found to play a significant role as it is closely associated with the quality of care.

Design: An observational cohort study among 313 consecutive patients who were admitted to the cardiac surgery intensive care unit of a general, tertiary hospital of Athens, Greece from November 2008 to November 2009.

Methods: Data collection was performed by using a short questionnaire (for basic demographic information) and two instruments, the Nursing Activities Score (NAS) and the logistic EuroSCORE, for assessing the NWL and the perioperative risk for each patient respectively.

Results: ICU‐LOS of more than 2 days increased with age and was more common among females (p < 0·001 and p = 0·02, respectively). Multivariate logistic regression analysis revealed a positive association between increased perioperative risk and the increased ICU‐LOS [odd ratio (OR) 1·9, 95% confidence interval (CI) 1·0–3·5, p = 0·04], while patients with a first day NAS of more than 61·6% had an almost 5·2 times greater probability to stay in the cardiac surgery unit for more than 2 days (OR 5·2, 95% CI 3·0–8·8, p < 0·001).

Conclusions: Increased level of NWL and patient perioperative risk are closely associated with increased ICU‐LOS.

Relevance to clinical practice: The correlation between patient perioperative risk and ICU‐LOS encourages the early identification of high‐risk patients for prolonged hospitalization. Furthermore, the relationship between NWL and ICU‐LOS allows the early identification of these patients with the use of an independent nursing tool.
Survival and reproduction of Liposcelis paeta (Pearman) (Psocoptera: Liposcelididae) when irradiated by electron beams
Authors: WANG Juanjuan , GUO Dongquan , FAN Jialin , CHEN Yuntang , ZHANG Jianwei , YANG Baoan , LI Xuzhao
Published: August 2011

Electron beam irradiation has been evaluated for the survival and reproduction of Liposcelis paeta Pearman (Psocoptera: Liposcelididae). All effects increased with increasing doses from 50 to 1000 Gy when the electron energy was 2 MeV. Eggs were unable to develop into adults following a dose of 100 Gy. Complete (100%) mortality was achieved about 5 weeks after adult emergence from nymphs irradiated at 300 Gy, whereas 100% mortality of adults was achieved 9 weeks after irradiation at 300 Gy. The fecundity was greatly reduced to 1.82% of that of control when L. paeta adults were irradiated at 250 Gy. A dose of 300 Gy caused complete reproductive sterility in adults. These results suggest that the most susceptible stage was the egg stage, then nymph and adult stages. A dose of 300 Gy is suggested for quarantine treatment of commodities infested by L. paeta.