bluuebunny/crossref_metadata_2025 huggingface dataset:
Environment versus dispersal in the assembly of western Amazonian palm communities
Authors: Kristiansen Thea , Svenning Jens‐Christian , Eiserhardt Wolf L. , Pedersen Dennis , Brix Hans , Munch Kristiansen Søren , Knadel Maria , Grández César , Balslev Henrik
Published: February 2012

Aim It is a central issue in ecology and biogeography to understand what governs community assembly and the maintenance of biodiversity in tropical rain forest ecosystems. A key question is the relative importance of environmental species sorting (niche assembly) and dispersal limitation (dispersal assembly), which we investigate using a large dataset from diverse palm communities.

Location Lowland rain forest, western Amazon River Basin, Peru.

Methods We inventoried palm communities, registering all palm individuals and recording environmental conditions in 149 transects of 5 m × 500 m. We used ordination, Mantel tests and indicator species analysis (ISA) to assess compositional patterns, species responses to geographical location and environmental factors. Mantel tests were used to assess the relative importance of geographical distance (as a proxy for dispersal limitation) and environmental differences as possible drivers of dissimilarity in palm species composition. We repeated the Mantel tests for subsets of species that differ in traits of likely importance for habitat specialization and dispersal (height and range size).

Results We found a strong relationship between compositional dissimilarity and environmental distance and a weaker but also significant relationship between compositional dissimilarity and geographical distance. Consistent with expectations, relationships with environmental and geographical distance were stronger for understorey species than for canopy species. Geographical distance had a higher correlation with compositional dissimilarity for small‐ranged species compared with large‐ranged species, whereas the opposite was true for environmental distance. The main environmental correlates were inundation and soil nutrient levels.

Main conclusions The assembly of palm communities in the western Amazon appears to be driven primarily by species sorting according to hydrology and soil, but with dispersal limitation also playing an important role. The importance of environmental characteristics and geographical distance varies depending on plant height and geographical range size in agreement with functional predictions, increasing our confidence in the inferred assembly mechanisms.
Presence of viable mould propagules in indoor air in relation to house damp and outdoor air
Authors: Verhoeff A. P. , van Wijnen J. H. , Brunekreef B. , Fischer P. , van Reenen‐Hoekstra E. S. , Samson R. A.
Published: February 2012

The presence of viable mould propagules in indoor air was investigated using the N6‐Andersen sampler in combination with DG18‐agar, in relation to house damp (characterized with a checklist) and in relation to the presence of moulds in outdoor air. The first part of the study was conducted in 46 houses in the autumn of 1987, the second part in 84 houses in May 1989. Further, in the second part, the results obtained with settlement plates (OPD) were compared with those obtained with the N6‐Andersen sampler. The number of CFU/m3 in the indoor and outdoor air varied widely. A large variety of mould genera and species was isolated. Species of Cladosporium, Penicillium and Wallemia predominated. The variability in time was high and the reproducibility of the measurements in terms of CFU/m3 and of species isolated was only moderate. The low predictive value of these measurements limits their use in epidemiological studies of the relationship between exposure to moulds and respiratory symptoms. Overall, the geometric mean concentration was somewhat higher outdoors than indoors. However, the clear differences found between the number of CFU/m3 belonging to different mould species in in‐ and outdoor air show that the presence of viable mould propagules in indoor air is not simply a reflection of the presence of moulds in outdoor air. The presence of moulds in indoor air was only weakly related to house damp as characterized by the checklist. High, statistically significant correlations were found between the CFU yield obtained with the OPD and the CFU/m3 yield obtained with the N6‐Andersen sampler. However, the number of species isolated with the OPD was significantly lower than that obtained with the N6‐Andersen sampler.
Study of the allergenic fractions of latex
Authors: Chambeyron C. , Dry J. , Leynadier F. , Pecquet C. , Thao Tran Xuan
Published: February 2012

Two latex (Hevea brasiliensis) raw materials, one from the cytosolic fraction, the other from the total natural latex have been characterised by immunoblotting techniques. The two latex fractions A and B were studied by immunoprints using eight sera from patients who were allergic to latex. They gave different profiles though there were also allergens of common molecular weights (60, 35, 30, 25, 20, 18, 15, and 10 kD). This study confirms the importance of allergic reactions to latex, that may in some patients cause anaphylactic shock.
Changes in natural killer cell subsets in pediatric liver transplant recipients
Authors: Pham Betty , Piard‐Ruster Karine , Silva Richard , Gallo Amy , Esquivel Carlos O. , Martinez Olivia M. , Krams Sheri M.
Published: February 2012

Pham B, Piard‐Ruster K, Silva R, Gallo A, Esquivel CO, Martinez OM, Krams SM. Changes in natural killer cell subsets in pediatric liver transplant recipients.  Pediatr Transplantation 2012: 16: 176–182. © 2012 John Wiley & Sons A/S.

Abstract:  NK cells are important in the immune response against tumors and virally infected cells. A balance between inhibitory and activating receptors controls the effector functions of NK cells. We examined the fate of circulating NK cells and the expression of the NK cell‐activating receptors in pediatric liver transplant recipients. Blood specimens were collected from 38 pediatric liver transplant recipients before transplant, and at one wk, one, three, six, and nine months, and one yr post‐transplant. PBMCs were isolated and analyzed for the levels of NK cell activation receptors NKp30, NKp46, and NKG2D in the CD56dimCD16+ and CD56brightCD16+/− subsets of NK cells. We demonstrated that there is a significant decrease in the percentage of circulating NK cells post‐transplant (pretransplant 7.69 ± 1.54 vs. one wk post‐transplant 1.73 ± 0.44) in pediatric liver transplant recipients. Interestingly, NKp30 expression is significantly increased, while NKp46 and NKG2D levels remain stable on the NK cells that persist at one wk post‐transplant. These data indicate that the numbers and subsets of circulating NK cells are altered in children after liver transplantation.
The effect of Gal expression on pig cells on the human T‐cell xenoresponse
Authors: Wilhite Tyler , Ezzelarab Corin , Hara Hidetaka , Long Cassandra , Ayares David , Cooper David K.C. , Ezzelarab Mohamed
Published: February 2012

Wilhite T, Ezzelarab C, Hara H, Long C, Ayares D, Cooper DKC, Ezzelarab M. The effect of Gal expression on pig cells on the human T cell xenoresponse. Xenotransplantation 2012; 19: 56–63. © 2012 John Wiley & Sons A/S.

Abstract:  Background:  Lack of Gal expression on pig cells is associated with a reduced primate humoral immune response as well as a reduction in cytokine production by human cells in vitro. We investigated whether lack of Gal expression is associated with reduced human T‐cell response in vitro.

Methods:  Peripheral blood mononuclear cells (PBMCs) were obtained from healthy humans and naïve baboons. Human CD4+ and CD8+ T cells were isolated. Porcine aortic endothelial cells (pAECs) were isolated from wild‐type (WT) and α1,3‐galactosyltransferase gene‐knockout (GTKO) pigs. WT pAECs were treated with α‐galactosidase, reducing Gal expression. Swine leukocyte antigen (SLA) class I and II expression on pAECs was measured, as was T‐cell proliferation and cytokine production in response to pAECs.

Results:  Reduced Gal expression on WT pAECs after α‐galactosidase treatment was associated with reduced human PBMC proliferation (P < 0.005). SLA class I and II expression on WT and GTKO pAECs was comparable. Human CD4+ and CD8+ T‐cell proliferation was less against GTKO pAECs before (P < 0.001) and after (P < 0.01 and P < 0.05, respectively) activation. Human and baboon PBMC proliferation was less against GTKO pAECs before (P < 0.05) and after (P < 0.01 and P < 0.05, respectively) activation. Human PBMCs produced a comparable cytokine/chemokine response to WT and GTKO pAECs. However, there was less production of IFN‐γ/TNF‐α by CD4+ and IFN‐γ/granzyme B/IP‐10 by CD8+ T cells in response to GTKO pAECs.

Conclusions:  The absence of Gal on pig cells is associated with reduced human T‐cell proliferation (and possibly selected cytokine production). Adaptive primate T‐cell responses are likely to be reduced in GTKO xenograft recipients.
Cellular and physiological mechanisms of new‐onset diabetes mellitus after solid organ transplantation
Authors: Dong M. , Parsaik A. K. , Eberhardt N. L. , Basu A. , Cosio F. G. , Kudva Y. C.
Published: February 2012

Diabet. Med. 29, e1–e12 (2012)

New‐onset diabetes after transplantation is recognized as one of the metabolic consequences which may increase the risk of morbidity and mortality after solid organ transplantation. The pathophysiology of new‐onset diabetes after transplantation has not been clearly defined and may resemble that of Type 2 diabetes, characterized by predominantly insulin resistance or defective insulin secretion, or both. This review aims to summarize the current state of knowledge regarding the prevalence, consequences, pathogenesis, and management of new‐onset diabetes after transplantation, with a major focus on the possible mechanisms involved in the pathogenesis of the disorder. The aetiology of new‐onset diabetes after transplantation is multifactorial, with diabetogenic immunosuppressive drugs playing a major role. Multiple cellular and physiologic mechanisms are involved in the process. Selection of an appropriate maintenance immunosuppressive regimen should involve balancing the risk of patient and graft survival vs. the potential for new‐onset diabetes after transplantation.
The Bologna Process: perspectives and implications for the Russian university
Authors: Telegina Galina , Schwengel Hermann
Published: February 2012

This article draws on the discourses of educational policy in Europe to focus on the implications of the Bologna Process for higher education in Russia. The Bologna Process, as a multi‐dimensional discourse involving a variety of social actors, reflects some of the complexities and contradictions of globalisation, in many local cases evoking responses and leading to outcomes which were neither planned nor predicted by the official educational policy planners. The role of international organisations in the reform of Russian higher education is considered and the barriers, limitations and possible consequences of Bologna for the Russian situation are explored.
The Influence of Academic Migration on the Intellectual Potential of Russia
Authors: Latova Natalia V. , Savinkov Vladimir I.
Published: February 2012

The emigration of highly‐qualified academics (‘brain drain’) is considered an essential factor in the decline of the human capital of post‐Soviet Russia. However, statistics show that the scale of this phenomenon since 2000 was minor. The Russian scientists who went abroad for permanent residence or for a contract job abroad represented no more than 2% of Russian scientists with Candidate or Doctor of Science degrees. Yet, at the same time, the relatively new concept of ‘brain circulation’ gains more popularity. The departure of Russian scientists abroad is not only a threat to the development of domestic science but, paradoxically, also the chance to give additional stimulus to its development.
The Role of Motor Experience in Understanding Action Function: The Case of the Precision Grasp
Authors: Loucks Jeff , Sommerville Jessica A.
Published: February 2012

Recent evidence suggests adults and infants selectively attend to features of action, such as how a hand contacts an object. The current research investigated whether this bias stems from infants’ processing of the functional consequences of grasps: understanding that different grasps afford different future actions. A habituation paradigm assessed 10‐month‐old infants’ (N = 62) understanding of the functional consequences of precision and whole‐hand grasps in others’ actions, and infants’ own precision grasping abilities were also assessed. The results indicate infants understood the functional consequences of another’s grasp only if they could perform precision grasps themselves. These results highlight a previously unknown aspect of early action understanding, and deepen our understanding of the relation between motor experience and cognition.
The Interplay Between Input and Initial Biases: Asymmetries in Vowel Perception During the First Year of Life
Authors: Pons Ferran , Albareda‐Castellot Bàrbara , Sebastián‐Gallés Núria
Published: February 2012

Vowels with extreme articulatory‐acoustic properties act as natural referents. Infant perceptual asymmetries point to an underlying bias favoring these referent vowels. However, as language experience is gathered, distributional frequency of speech sounds could modify this initial bias. The perception of the /i/–/e/ contrast was explored in 144 Catalan‐ and Spanish‐learning infants (2 languages with a different distribution of vowel frequency of occurrence) at 4, 6, and 12 months. The results confirmed an acoustic bias at 4 and 6 months in all infants. However, at 12 months, discrimination was not affected by the acoustic bias but by the frequency of occurrence of the vowel.
On Reciprocal Equivalence of Stäckel Systems
Authors: Błaszak Maciej , Marciniak Krzysztof
Published: February 2012

In this paper we investigate Stäckel transforms between different classes of parameter‐dependent Stäckel separable systems of the same dimension. We show that the set of all Stäckel systems of the same dimension splits to equivalence classes so that all members within the same class can be connected by a single Stäckel transform. We also give an explicit formula relating solutions of two Stäckel‐related systems. These results show in particular that any two geodesic Stäckel systems are Stäckel equivalent in the sense that it is possible to transform one into another by a single Stäckel transform. We also simplify proofs of some known statements about multiparameter Stäckel transform.
Complete Group Classification and Exact Solutions to the Generalized Short Pulse Equation
Authors: Liu H. , Li J. , Liu L.
Published: February 2012

In this paper, the complete group classification is performed on the generalized short pulse equation, which includes a lot of important nonlinear wave equations as its special cases. In the sense of geometric symmetry, all of the vector fields of the equation are obtained in terms of the arbitrary functions. Then, the symmetry reductions and exact solutions to the equations are investigated. Especially, we develop the analytic power series method for constructing the exact power series solutions to the short pulse types of equations.
Royal finance under King Henry III, 1216–72: the wardrobe evidence1
Authors: Wild Benjamin L.
Published: February 2012

Existing studies have shown how the royal wardrobe, the king's personal administrative office, regularly handled between a quarter and a half of the Crown's annual cash income. Despite this, the financial contribution of the wardrobe to royal finance under Henry III is not fully understood. For a reign in which debates about royal fiscal strategies are so notable a feature, this represents a significant gap. This article will supplement existing studies of wardrobe finance under Henry III by collectively analysing all 15 of the king's wardrobe accounts that are enrolled on the exchequer pipe rolls. The article makes two important findings. Firstly, the wardrobe was financially strong when the period of baronial reform began in 1258. Secondly, the wardrobe's financial strength was the result of a new, and deliberate, approach to acquiring revenue beyond the treasury that targeted sources of income that could generate cash quickly. During Henry's final years, this included greater reliance on credit. These findings suggest Henry III was not incapable of making adroit financial decisions. They also reveal that the foundations for the financial system developed by the three Edwards, which was more reliant on credit and sources of ready cash, were laid under Henry III.
Socioeconomic Implications of the Increasing Foreign Remittance to Nepal: Evidence from the Nepal Living Standard Survey
Authors: Wagle Udaya R.
Published: February 2012

The period since the 1990s witnessed a strong economic performance and labour demand in many countries in the Middle East, East Asia, and West, which coincided with the major political turmoil in Nepal causing enormous increase in emigration and foreign remittance. Using micro‐data for 1996 and 2004, this paper examines foreign remittance to Nepal and its socioeconomic implications. Data indicate that foreign remittance has helped increase income sizably and reduce poverty and income inequality marginally. Various family and individual characteristics are used to test whether the socioeconomically disadvantaged groups such as those with low non‐remittance income and assets, low caste and ethnic backgrounds, and from rural areas and remote regions benefited equally from foreign remittance. Analytical strategy involved estimating regressions of foreign remittance using the Generalized Least Squares estimator for families with foreign remittance and Three Stage Least Squares estimator for all families to minimize self‐selection and simultaneous causality bias. Although non‐remittance income and some of the low caste, ethnic, and spatiality backgrounds showed less consistent relationships, findings suggest that smaller families particularly with low asset‐holding and socioeconomic backgrounds were likely to receive less remittance. These findings highlight an important progress that the Nepali society is making toward levelling the playing field in foreign employment and remittance with migration to the regions and countries other than India offering better remittance prospects. Yet, further policy efforts are needed to ensure that foreign employment and remittance do not exacerbate the increasingly polarizing economic structure leaving the bottom sections of the society further worse off.
Remittances and the Maintenance of Dual Social Worlds: The Transnational Working Lives of Migrants in Greater London
Authors: Batnitzky Adina , McDowell Linda , Dyer Sarah
Published: February 2012

Most research on remittances focuses on economic motivations, with little emphasis on the social contexts in which the remittance economy operates. Through an analysis of in‐depth interviews with migrant workers in a London hotel and hospital, we examine how migrants’ familial and social relationships in both sending and receiving countries inform the decision to send remittances. We suggest that remittances are a mechanism through which migrants are able to fulfil multiple obligations to families and places of origin, while also enhancing their own economic status and future. First, satisfying the cultural expectation of sending remittances helps migrants maintain their social worlds at “home”. Second, we observed that both positive and negative changes in power and resources influence the decision to send remittances by motivating migrants to invest in their social position in either their home or receiving country. In sum, we argue that the migrants’ social experience in the United Kingdom might be just as predictive of remittance behaviour as their economic and social status in the country of origin. We, therefore, call for a need to move beyond the often one‐sided concern with development by concentrating on the overlapping social worlds of migrants.
Coronary artery wall imaging in mice using osmium tetroxide and micro‐computed tomography (micro‐CT)
Authors: Pai Vinay M. , Kozlowski Megan , Donahue Danielle , Miller Elishiah , Xiao Xianghui , Chen Marcus Y. , Yu Zu‐Xi , Connelly Patricia , Jeffries Kenneth , Wen Han
Published: February 2012

The high spatial resolution of micro‐computed tomography (micro‐CT) is ideal for 3D imaging of coronary arteries in intact mouse heart specimens. Previously, micro‐CT of mouse heart specimens utilized intravascular contrast agents that hardened within the vessel lumen and allowed a vascular cast to be made. However, for mouse coronary artery disease models, it is highly desirable to image coronary artery walls and highlight plaques. For this purpose, we describe an ex vivo contrast‐enhanced micro‐CT imaging technique based on tissue staining with osmium tetroxide (OsO4) solution. As a tissue‐staining contrast agent, OsO4 is retained in the vessel wall and surrounding tissue during the fixation process and cleared from the vessel lumens. Its high X‐ray attenuation makes the artery wall visible in CT. Additionally, since OsO4 preferentially binds to lipids, it highlights lipid deposition in the artery wall. We performed micro‐CT of heart specimens of 5‐ to 25‐week‐old C57BL/6 wild‐type mice and 5‐ to 13‐week‐old apolipoprotein E knockout (apoE−/−) mice at 10 μm resolution. The results show that walls of coronary arteries as small as 45 μm in diameter are visible using a table‐top micro‐CT scanner. Similar image clarity was achieved with 1/2000th the scan time using a synchrotron CT scanner. In 13‐week‐old apoE mice, lipid‐rich plaques are visible in the aorta. Our study shows that the combination of OsO4 and micro‐CT permits the visualization of the coronary artery wall in intact mouse hearts.
Packing a pinch: functional implications of chela shapes in scorpions using finite element analysis
Authors: van der Meijden Arie , Kleinteich Thomas , Coelho Pedro
Published: February 2012

Scorpions depend on their pedipalps for prey capture, defense, mating and sensing their environment. Some species additionally use their pedipalps for burrowing or climbing. Because the pincers or chelae at the end of the pedipalps vary widely in shape, they have been used as part of a suite of characters to delimit ecomorphotypes. We here evaluate the influence of the different chela cuticular shapes on their performance under natural loading conditions. Chelae of 20 species, representing seven families and spanning most of the range of chela morphologies, were assigned to clusters based on chela shape parameters using hierarchical cluster analysis. Several clusters were identified corresponding approximately to described scorpion ecomorphotypes. Finite element models of the chela cuticulae were constructed from CT scans and loaded with estimated pinch forces based onin vivoforce measurements. Chela shape clusters differed significantly in mean Von Mises stress and strain energy. Normalized FEA showed that chela shape significantly influenced Von Mises stress and strain energy in the chela cuticula, with Von Mises stress varying up to an order of magnitude and strain energy up to two orders of magnitude. More elongate, high‐aspect ratio chela forms showed significantly higher mean stress compared with more robust low‐aspect ratio forms. This suggests that elongate chelae are at a higher risk of failure when operating near the maximum pinch force. Phylogenetic independent contrasts (PIC) were calculated based on a partly resolved phylogram with branch lengths based on an alignment of the 12S, 16S and CO1 mitochondrial genes. PIC showed that cuticular stress and strain in the chela were correlated with several shape parameters, such as aspect ratio, movable finger length, and chela height, independently of phylogenetic history. Our results indicate that slender chela morphologies may be less suitable for high‐force functions such as burrowing and defense. Further implications of these findings for the ecology and evolution of the different chela morphologies are discussed.
Annual Research Review: Embracing not erasing contextual variability in children’s behavior – theory and utility in the selection and use of methods and informants in developmental psychopathology
Authors: Dirks Melanie A. , De Los Reyes Andres , Briggs‐Gowan Margaret , Cella David , Wakschlag Lauren S.
Published: February 2012

This paper examines the selection and use of multiple methods and informants for the assessment of disruptive behavior syndromes and attention deficit/hyperactivity disorder, providing a critical discussion of (a) the bidirectional linkages between theoretical models of childhood psychopathology and current assessment techniques; and (b) current knowledge concerning the utility of different methods and informants for key clinical goals. There is growing recognition that children’s behavior varies meaningfully across situations, and evidence indicates that these differences, in combination with informants’ unique perspectives, are at least partly responsible for inter‐rater discrepancies in reports of symptomatology. Such data suggest that we should embrace this contextual variability as clinically meaningful information, moving away from models of psychopathology as generalized traits that manifest uniformly across situations and settings, and toward theoretical conceptualizations that explicitly incorporate contextual features, such as considering clinical syndromes identified by different informants to be discrete phenomena. We highlight different approaches to measurement that embrace contextual variability in children’s behavior and describe how the use of such tools and techniques may yield significant gains clinically (e.g., for treatment planning and monitoring). The continued development of a variety of feasible, contextually sensitive methods for assessing children’s behavior will allow us to determine further the validity of incorporating contextual features into models of developmental psychopathology and nosological frameworks.
Mitochondrial basis of the anti‐arrhythmic action of lidocaine and modulation by the n‐6 to n‐3 PUFA ratio of cardiac phospholipids
Authors: Demaison Luc , Moreau Daniel , Clauw Fabienne , Vergely Catherine , Rochette Luc
Published: February 2012

The aim of this study was to evaluate the involvement of mitochondria in the mechanism of the anti‐arrhythmic lidocaine. Rats were fed with a diet containing either n‐6 polyunsaturated fatty acids (PUFAs, SSO group) or an equimolecular mixture of n‐3 and n‐6 PUFAs (FO group) for 8 weeks. The hearts were perfused according to the working mode using a medium with or without lidocaine 5 μm. They were then subjected to local ischemia (20 min) and reperfusion (30 min). Dietary n‐3 PUFAs triggered the expected decrease in the n‐6/n‐3 PUFA ratio of cardiac phospholipids. Reperfusing the ischemic area favored the incidence of severe arrhythmias. Lidocaine treatment abolished almost completely reperfusion arrhythmias in the FO group, but did not display anti‐arrhythmic properties in the SSO group. As it was indicated by measurements of the mitochondrial function, lidocaine seemed to favor mitochondrial calcium retention in the FO group, which might prevent cytosolic calcium spikes and reperfusion arrhythmias. In the SSO group, the resistance to lidocaine was associated with an aggravation of cellular damages. The mitochondrial calcium retention capacities were saturated, and lidocaine was unable to increase them, making the drug inefficient in preventing reperfusion arrhythmias.
Personality and body condition have additive effects on motivation to feed in Zebra Finches Taeniopygia guttata
Authors: DAVID MORGAN , AUCLAIR YANNICK , GIRALDEAU LUC‐ALAIN , CÉZILLY FRANK
Published: February 2012

Several hypotheses have been proposed to account for the adaptive evolution of personality, defined as inter‐individual differences in behaviour that are consistent over time and across situations. For instance, the ‘pace‐of‐life syndrome’ hypothesis suggests that personality evolved as a behavioural correlate of life‐history trajectories that vary within populations. Thus, proactivity, corresponding to higher exploratory tendencies or higher boldness levels, has been linked to higher productivity or mortality rates. However, the extent to which proactivity is associated with a higher motivation to forage remains poorly understood. Moreover, although personality and its effects on foraging behaviour are usually considered to be independent of any motivational or nutritional state, few studies so far have challenged this. Here we show that personality traits, both individually or combined using a principal component analysis, and body condition have additive effects on latency to feed following food deprivation in the Zebra Finch Taeniopygia guttata, with personality accounting for 41% and body condition for about 20% of the total variation in latency to feed. In accordance with the pace‐of‐life syndrome hypothesis, latency to feed was negatively related to the degree of proactivity and positively related to body condition. Thus, proactive individuals and individuals in poorer condition were quicker to start feeding after a period of food deprivation. The absence of a significant interaction between personality and body condition further suggests that the effect of personality was independent of body condition. We discuss the relevance of our results in relation to the different factors influencing foraging in birds. Moreover, we place our results within a life‐history framework by emphasizing the correlated evolution of life‐history traits and personality.
Land degradation in Mediterranean urban areas: an unexplored link with planning?
Authors: Salvati Luca , Gemmiti Roberta , Perini Luigi
Published: February 2012

This paper examines the role of biophysical and anthropogenic factors as potential drivers of land degradation in a large Mediterranean urban region. The sensitivity of land to degradation is examined in relation to the territorial disparities observed within Rome's metropolitan area (Italy), and to the changes in its spatial organisation resulting from urban shrinkage. We derive a composite index of land sensitivity to degradation using the Environmentally Sensitive Areas Index (ESAI) at the municipal level. The observed regional disparities in ESAI scores are analysed diachronically for the period 1990–2008, based on elevation, distance from the coast and population density. The results indicate that spatial disparities in ESAI recorded in 1990 had decreased by 2008, although the degree of land sensitivity had increased throughout the urban region. We subsequently relate these changes to different models of urban organisation (i.e. ‘compact growth’ vs ‘sprawl’) observed in Rome since the 1990s. In 1990, the highest degree of land sensitivity was on the urban fringe of Rome, whereas by 2008 the greatest increase in land sensitivity was observed within suburban municipalities. This sensitivity progressively spread further away from the main urban centre during the study period. The results suggest the need to reconsider the polycentric spatial framework as an environmentally sustainable model for Rome and other urban regions in the Mediterranean.
Scarcity, frontiers and development
Authors: BARBIER EDWARD B
Published: February 2012

Resource and land frontiers have always been a significant focus of geography but have become overlooked in economics and economic history. Yet a critical driving force behind global economic development has been the response of human society to natural resource scarcity, not just through conserving scarce resources but also by obtaining and developing more of them. A handful of theories of how such classic frontier expansion has shaped economic development have been formulated, and these are discussed and reviewed. Evidence from history is cited to illustrate these effects, and the implications for resource‐based development in the Contemporary Era (1950 to present) are discussed. Unlike previous eras, the pattern of frontier expansion is dualistic. This has led to less economy‐wide benefits from frontier‐based development in the Contemporary Era.
Platelet transfusions: treatment options for hemorrhage secondary to thrombocytopenia
Authors: Hux Bryan D. , Martin Linda G.
Published: February 2012

Objective

To review current human and veterinary protocols for platelet transfusion triggers, available platelet transfusion products to support veterinary thrombocytopenic patients, and the advantages and disadvantages of each product.

Data Sources

Data from human and veterinary literature.

Human Data Synthesis

Prophylactic and therapeutic platelet transfusions are instrumental in managing human patients with thrombocytopenia. The platelet transfusion products used in human medicine consist of platelet concentrates, derived from pooled random donor platelets, or single‐donor apheresis platelets. Historically, platelet transfusions in human medicine have been prophylactic in nature; however, recent research suggests changing from a prophylactic transfusion strategy to a therapeutic transfusion strategy may be safe for most patients. The optimal platelet transfusion trigger and the use of prophylactic verses therapeutic platelet transfusions are ever changing in human medicine.

Veterinary Data Synthesis

There have been many advances in platelet transfusion products, but fresh whole blood remains the most commonly used platelet transfusion product in veterinary medicine. New products such as lyophilized platelets and cryopreserved platelets offer the benefits of long shelf life, immediate availability, and higher concentration of platelets at smaller doses. Veterinary platelet transfusion guidelines are mostly extrapolated from human literature because data on veterinary platelet transfusions are lacking.

Conclusions

In veterinary medicine the most commonly available product for platelet transfusions is fresh whole blood, because of availability of blood donors and lack of a cost effective easily obtainable alternative. Cryopreserved and lyophilized platelets are promising new products being used in the treatment of hemorrhaging patients with thrombocytopenia. These products offer increased platelet concentrations at decreased volumes, longer storage shelf life, and decreased exposure to whole blood products. With the development of newer readily available products, platelet transfusion parameters, to include dose, platelet count trigger, presence of disease, and clinical signs, should be further evaluated in veterinary medicine.
Diagnosis and treatment of platelet hyperactivity in relation to thrombosis in dogs and cats
Authors: Wiinberg Bo , Jessen Lisbeth R. , Tarnow Inge , Kristensen Annemarie T.
Published: February 2012

Objective

To review the mechanisms of platelet activation and options for diagnosing and treating platelet hyperactivity in relation to thrombosis in dogs and cats.

Data Sources

Prospective, retrospective, and review articles, as well as textbook chapters in both human and veterinary medicine. Articles were primarily, but not exclusively, retrieved viaMedline.

Human Data Synthesis

In people, platelets are known to play a key role in the development of arterial thrombosis in numerous disease states and antiplatelet drugs are the cornerstone in the treatment of acute events and for prevention in patients at risk. For many years, aspirin was used as the sole antiplatelet drug in people, but the introduction of adenosine diphosphate receptor antagonists and integrin αIIbβ3inhibitors has significantly improved outcome in selective groups of patients.

Veterinary Data Synthesis

The understanding of platelet activation in disease states has increased dramatically over the past decade. Simultaneously, a host of new methods for evaluating platelet function have been developed, which enable primarily researchers, but also clinicians to monitor the activity of platelets. Many of these methods have been validated for research purposes, but few have found their way to the clinics. Not a single correctly randomized clinical trial has been carried out with any antiplatelet drug for any indication in dogs or cats, and consequently, treatment is empiric and largely based on expert opinion or data from experimental studies.

Conclusions

The pathogenesis of thromboembolic disease is complex and multifactorial and the role of hyperactive platelets in this etiology remains to be clarified in most of the diseases associated with thrombosis in dogs and cats. Until efficacy data from well‐designed studies are available, antithrombotic therapy should consist of close monitoring, good supportive care, and judicious empirical use of antiplatelet agents.
The relationship between the MMP system, adrenoceptors and phosphoprotein phosphatases
Authors: Rietz A , Spiers JP
Published: February 2012

The MMPs and their inhibitors [tissue inhibitor of MMPs (TIMPs) ] form the mainstay of extracellular matrix homeostasis. They are expressed in response to numerous stimuli including cytokines and GPCR activation. This review highlights the importance of adrenoceptors and phosphoprotein phosphatases (PPP) in regulating MMPs in the cardiovascular system, which may help explain some of the beneficial effects of targeting the adrenoceptor system in tissue remodelling and will establish emerging crosstalk between these three systems. Although α‐ and β‐adrenoceptor activation increases MMP but decreases TIMP expression, MMPs are implicated in the growth stimulatory effects of adrenoceptor activation through transactivation of epidermal growth factor receptor. Furthermore, they have recently been found to catalyse the proteolysis of β‐adrenoceptors and modulate vascular tone. While the mechanisms underpinning these effects are not well defined, reversible protein phosphorylation by kinases and phosphatases may be key. In particular, PPP (Ser/Thr phosphatases) are not only critical in resensitization and internalization of adrenoceptors but also modulate MMP expression. The interrelationship is complex as isoprenaline (ISO) inhibits okadaic acid [phosphoprotein phosphatase type 1/phosphoprotein phosphatase type 2A (PP2A) inhibitor]‐mediated MMP expression. While this may be simply due to its ability to transiently increase PP2A activity, there is evidence for MMP‐9 that ISO prevents okadaic acid‐mediated expression of MMP‐9 through a β‐arrestin, NF‐κB‐dependent pathway, which is abolished by knock‐down of PP2A. It is essential that crosstalk between MMPs, adrenoceptors and PPP are investigated further as it will provide important insight into how adrenoceptors modulate cardiovascular remodelling, and may identify new targets for pharmacological manipulation of the MMP system.
Task‐Based Language Teaching in Online Ab Initio Foreign Language Classrooms
Authors: LAI CHUN , ZHAO YONG , WANG JIAWEN
Published: February 2012

Task‐based language teaching (TBLT) has been attracting the attention of researchers for more than 2 decades. Research on various aspects of TBLT has been accumulating, including the evaluation studies on the implementation of TBLT in classrooms. The evaluation studies on students’ and teachers’ reactions to TBLT in the online courses are starting to gain momentum, and this study adds to this line of research by enhancing our understanding of the implementation of TBLT in an online ab initio course. This study investigated the implementation of a TBLT syllabus in an ab initio online Chinese as foreign language course over a semester. Surveys and interviews with the students and the instructors revealed that students reacted positively to the online TBLT experience, and analyses of students’ performance at the end of the semester suggested that this pedagogy produced good learning outcomes. This study also identified some challenges and advantages of the online context for TBLT.
Bayesian Effect Estimation Accounting for Adjustment Uncertainty
Authors: Wang Chi , Parmigiani Giovanni , Dominici Francesca
Published: February 2012

Summary Model‐based estimation of the effect of an exposure on an outcome is generally sensitive to the choice of which confounding factors are included in the model. We propose a new approach, which we call Bayesian adjustment for confounding (BAC), to estimate the effect of an exposure of interest on the outcome, while accounting for the uncertainty in the choice of confounders. Our approach is based on specifying two models: (1) the outcome as a function of the exposure and the potential confounders (the outcome model); and (2) the exposure as a function of the potential confounders (the exposure model). We consider Bayesian variable selection on both models and link the two by introducing a dependence parameter, , denoting the prior odds of including a predictor in the outcome model, given that the same predictor is in the exposure model. In the absence of dependence (), BAC reduces to traditional Bayesian model averaging (BMA). In simulation studies, we show that BAC, with estimates the exposure effect with smaller bias than traditional BMA, and improved coverage. We, then, compare BAC, a recent approach of Crainiceanu, Dominici, and Parmigiani (2008, Biometrika95, 635–651), and traditional BMA in a time series data set of hospital admissions, air pollution levels, and weather variables in Nassau, NY for the period 1999–2005. Using each approach, we estimate the short‐term effects of on emergency admissions for cardiovascular diseases, accounting for confounding. This application illustrates the potentially significant pitfalls of misusing variable selection methods in the context of adjustment uncertainty.
Evolutionary Factor Analysis of Replicated Time Series
Authors: Motta Giovanni , Ombao Hernando
Published: February 2012

SummaryIn this article, we develop a novel method that explains the dynamic structure of multi‐channel electroencephalograms (EEGs) recorded from several trials in a motor–visual task experiment. Preliminary analyses of our data suggest two statistical challenges. First, the variance at each channel and cross‐covariance between each pair of channels evolve over time. Moreover, the cross‐covariance profiles display a common structure across all pairs, and these features consistently appear across all trials. In the light of these features, we develop a novel evolutionary factor model (EFM) for multi‐channel EEG data that systematically integrates information across replicated trials and allows for smoothly time‐varying factor loadings. The individual EEGs series share common features across trials, thus, suggesting the need to pool information across trials, which motivates the use of the EFM for replicated time series. We explain the common co‐movements of EEG signals through the existence of a small number of common factors. These latent factors are primarily responsible for processing the visual–motor task which, through the loadings, drive the behavior of the signals observed at different channels. The estimation of the time‐varying loadings is based on the spectral decomposition of the estimated time‐varying covariance matrix.
The effect of hemodialysis ultrafiltration on changes in whole blood viscosity
Authors: Shirazian Shayan , Rios‐Rojas Liliana , Drakakis James , Dikkala Sudharani , Dutka Paula , Duey Marc , Cho Daniel J. , Fishbane Steven
Published: February 2012

Increased whole blood viscosity (WBV) can be injurious to the vascular endothelium and increase the risk of atherothrombotic events. This study examined the effect of hemodialysis ultrafiltration (UF) on WBV, with a focus on high vs. low‐volume UF patients. In stable hemodialysis patients, blood was drawn for hematocrit (Hct) and WBV at the start, midpoint, and at the end of dialysis. For analysis, patients were divided into high UF (≥2700 mL) or low UF (<2700 mL) groups. A total of 59 patients completed the study. Mean Hct increased during dialysis in both groups. The intradialytic increase in Hct was significantly greater in the high vs. the low UF group (3.2% vs. 1.28%, P = 0.01), with a significantly higher end‐dialysis Hct in the high UF group (40.5% vs. 38%, P = 0.02). At the end of dialysis, both high shear rate WBV (P < 0.01) and low shear rate WBV (P < 0.01) were significantly higher in the high UF compared with the low UF group. There was an approximately two‐fold greater increase in high shear rate (P < 0.01) and low shear rate (P = 0.01) WBV during dialysis in high vs. low UF groups. The increase in high shear rate WBV during dialysis was significantly correlated with an increase in Hct (R2 = 0.63, P < 0.01). We found that hemodialysis UF causes a surge in WBV. The surge was of greater magnitude in high than in low UF patients.
Dilator venotomy technique for placement of hemodialysis catheter following recanalization of occluded central vein
Authors: Pua Uei
Published: February 2012

Recanalization of occluded central veins for insertion of hemodialysis catheter is a particular attractive option in patients who are catheter dependent for hemodialysis, as it delays exhaustion of conventional venous accesses. Literature detailing techniques for catheter placement in recanalized veins remain sparse. We hereby describe a safe and economical technique of using dilator venotomy to allow catheter placement following successful recanalization.
In‐vitro Degradation and Bioactivity of Tailored Amorphous Multi Porous Scaffold Structure
Authors: Zhang Di , Jain Himanshu , Hupa Mikko , Hupa Leena
Published: February 2012

A key requirement for the use of bio scaffold is that its degradation rate matches the growth rate of target tissue. Therefore, the degradation of recently developed tailored amorphous multiporous (TAMP) scaffold of 70SiO2·30CaO (mol%) in simulated body fluid (SBF) was studied under both static and quasi‐dynamic conditions. The degradation was assessed through the dissolution of silica from the glass into SBF, while the in‐vitro bioactivity was characterized by precipitation of calcium phosphate (CaP) on and inside the scaffold. Under static conditions, the degradation stopped due to the saturation of solution with silica in 3 days, whereas the precipitation of CaP continued. Rapid degradation and better in‐vitro bioactivity was found under quasi‐dynamic conditions, where the concentration gradient across the sample was maintained. The degradation followed exponential dependence on time with a half‐life of 15.4 days and initial degradation rate 4.5% day−1. The remaining samples maintained their integrity and pore structure during degradation. The degradation occurred in three distinct stages: (a) wetting stage, (b) initial degradation stage when CaP precipitation dominates, and (c) intensive degradation stage when the nanopores rupture and network dissolves. By varying the sintering parameters the nanopore structure, and hence the degradation rate, can be tailored to suit the anticipated tissue regeneration rate. With demonstrated rapid and controllable degradation and good in‐vitro bioactivity, the TAMP scaffold shows promise as candidate for bone regeneration application under various conditions in the body.
Factors shaping the development of working time regulation in the United States and Europe
Authors: Dembe Allard E.
Published: February 2012

In nineteenth century Britain, the first working time regulations were prompted by humanitarian concerns about women and children employed in factories. In the United States, working time laws were initially introduced in response to union activism and labour unrest. During the twentieth century, policy‐makers enacted statutes that shortened hours of work in an attempt to spread available work and thereby curb unemployment. The past 20 years, with the adoption of the European Working Time Directive, have reflected a movement towards social and political integration, continuing political pressure to curb unemployment, and growing acceptance of ergonomics and work organization as components of international safety regulation.