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Atmospheric effects of the emerging mainland Chinese transportation system at and beyond the regional scale
Local surface travel needs in the People's Republic of China (mainland China) have traditionally been met largely by nonpolluting bicycles. A major automobile manufacturing/importing effort has begun in the country over the last decade, and planning documents indicate that the Chinese may strive to acquire more than 100 million vehicles early in the next century. By analogy with large automotive fleets already existing in the western world, both regional and global scale pollution effects are to be expected from the increase. The present work adopts the latest projections of Chinese automobile manufacture and performs some quantitative assessments of the extent of pollution generation. Focus for the investigation is placed upon the oxidant ozone. Emissions of the precursor species nitrogen oxides and volatile organics are constructed based on data for the current automotive sector in the eastern portion of the United States. Ozone production is first estimated from measured values for continental/oceanic scale yields relative to precursor oxidation. The estimates are then corroborated through idealized two dimensional modeling of the photochemistry taking place in springtime air flow off the Asian land mass and toward the Pacific Ocean. The projected fleet sizes could increase coastal and remote oceanic ozone concentrations by tens of parts per billion (ppb) in the lower troposphere. Influences on the tropospheric aerosol system and on the major greenhouse gas carbon dioxide are treated peripherally. Nitrogen oxides created during the vehicular internal combustion process will contribute to nitrate pollution levels measured in the open Pacific. The potential for soot and fugitive dust increases should be considered as the automotive infrastructure develops. Since the emerging Chinese automotive transportation system will represent a substantial addition to the global fleet and all the carbon in gasoline is eventually oxidized completely, a significant rise in global carbon dioxide inputs will ensue as well. Some policy issues are treated preliminary. The assumption is made that alterations to regional oxidant/aerosol systems and to terrestrial climate are conceivable. The likelihood that the Chinese can achieve the latest vehicle fleet goals is discussed, from the points of view of new production, positive pollution feedbacks from a growing automobile industry, and known petroleum reserves. Vehicular fuel and maintenance options lying before the Chinese are outlines and compared. To provide some perspective on the magnitude of the environmental changes associated with an Asian automotive buildup, recent estimates of the effects of future air traffic over the Pacific Rim are described
Economic burden of disease of uncontrolled acromegalic patients : the acromegaly Italian collaborative study group
Background: Acromegaly is a rare, serious and disabling disease associated with increased mortality if not properly treated. The objective of this study was to estimate indirect and direct costs associated to uncontrolled acromegalic patients in Italy. Methods: a specific questionnaire was developed in order to obtain specific information from the patient perspective and administrated to subsequent patients treated in 17 Italian endocrinology centres. Indirect cost from patients and caregivers perspective were estimated considering the Human Capital Approach while direct cost were evaluated considering the patients perspective. assuming that our sample were representative of the general uncontrolled acromegalic patients. Results: 86 patients were enrolled in the study and complete the questionnaire. Of these 51.16% were employed, 23.26% were unemployed for reasons unrelated to the illness, 8,14% were unemployed due to the illness and 17.44% were inactive. The total costs per patient amounted to about € 3,832 per year, of which 5.1% are mobility costs, while the indirect costs come to € 7.7 million, of which 45.7% is due to illness-related to unemployment. Conclusions: To our knowledge, this study represents the first attempt to quantify the costs of uncontrolled acromegalic patients in Italy
Complex circular subsidence structures in tephra deposited on large blocks of ice: Varða tuff cone, Öræfajökull, Iceland
Several broadly circular structures up to 16 m in diameter, into which higher strata have sagged and locally collapsed, are present in a tephra outcrop on southwest Öræfajökull, southern Iceland. The tephra was sourced in a nearby basaltic tuff cone at Varða. The structures have not previously been described in tuff cones, and they probably formed by the melting out of large buried blocks of ice emplaced during a preceding jökulhlaup that may have been triggered by a subglacial eruption within the Öræfajökull ice cap. They are named ice-melt subsidence structures, and they are analogous to kettle holes that are commonly found in proglacial sandurs and some lahars sourced in ice-clad volcanoes. The internal structure is better exposed in the Varða examples because of an absence of fluvial infilling and reworking, and erosion of the outcrop to reveal the deeper geometry. The ice-melt subsidence structures at Varða are a proxy for buried ice. They are the only known evidence for a subglacial eruption and associated jökulhlaup that created the ice blocks. The recognition of such structures elsewhere will be useful in reconstructing more complete regional volcanic histories as well as for identifying ice-proximal settings during palaeoenvironmental investigations
A bi-directional relationship between obesity and health-related quality of life : evidence from the longitudinal AusDiab study
Objective: To assess the prospective relationship between obesity and health-related quality of life, including a novel assessment of the impact of health-related quality of life on weight gain.Design and setting: Longitudinal, national, population-based Australian Diabetes, Obesity and Lifestyle (AusDiab) study, with surveys conducted in 1999/2000 and 2004/2005.Participants: A total of 5985 men and women aged 25 years at study entry.Main outcome measure(s): At both time points, height, weight and waist circumference were measured and self-report data on health-related quality of life from the SF-36 questionnaire were obtained. Cross-sectional and bi-directional, prospective associations between obesity categories and health-related quality of life were assessed.Results: Higher body mass index (BMI) at baseline was associated with deterioration in health-related quality of life over 5 years for seven of the eight health-related quality of life domains in women (all P0.01, with the exception of mental health, P>0.05), and six out of eight in men (all P<0.05, with the exception of role-emotional, P=0.055, and mental health, P>0.05). Each of the quality-of-life domains related to mental health as well as the mental component summary were inversely associated with BMI change (all P<0.0001 for women and P0.01 for men), with the exception of vitality, which was significant in women only (P=0.008). For the physical domains, change in BMI was inversely associated with baseline general health in women only (P=0.023).Conclusions: Obesity was associated with a deterioration in health-related quality of life (including both physical and mental health domains) in this cohort of Australian adults followed over 5 years. Health-related quality of life was also a predictor of weight gain over 5 years, indicating a bi-directional association between obesity and health-related quality of life. The identification of those with poor health-related quality of life may be important in assessing the risk of future weight gain, and a focus on health-related quality of life may be beneficial in weight management strategies.<br /
Phylogenetic Codivergence Supports Coevolution of Mimetic Heliconius Butterflies
The unpalatable and warning-patterned butterflies _Heliconius erato_ and _Heliconius melpomene_ provide the best studied example of mutualistic Müllerian mimicry, thought – but rarely demonstrated – to promote coevolution. Some of the strongest available evidence for coevolution comes from phylogenetic codivergence, the parallel divergence of ecologically associated lineages. Early evolutionary reconstructions suggested codivergence between mimetic populations of _H. erato_ and _H. melpomene_, and this was initially hailed as the most striking known case of coevolution. However, subsequent molecular phylogenetic analyses found discrepancies in phylogenetic branching patterns and timing (topological and temporal incongruence) that argued against codivergence. We present the first explicit cophylogenetic test of codivergence between mimetic populations of _H. erato_ and _H. melpomene_, and re-examine the timing of these radiations. We find statistically significant topological congruence between multilocus coalescent population phylogenies of _H. erato_ and _H. melpomene_, supporting repeated codivergence of mimetic populations. Divergence time estimates, based on a Bayesian coalescent model, suggest that the evolutionary radiations of _H. erato_ and _H. melpomene_ occurred over the same time period, and are compatible with a series of temporally congruent codivergence events. This evidence supports a history of reciprocal coevolution between Müllerian co-mimics characterised by phylogenetic codivergence and parallel phenotypic change
Using self-organizing maps to investigate environmental factors regulating colony size and breeding success of the White Stork (Ciconia ciconia)
We studied variations in the size of breeding colonies and in breeding performance of White Storks Ciconia ciconia in 2006–2008 in north-east Algeria. Each colony site was characterized using 12 environmental variables describing the physical environment, land-cover categories, and human activities, and by three demographic parameters: the number of breeding pairs, the number of pairs with chicks, and the number of fledged chicks per pair. Generalized linear mixed models and the self-organizing map algorithm (SOM, neural network) were used to investigate effects of biotic, abiotic, and anthropogenic factors on demographic parameters and on their relationships. Numbers of breeding pairs and of pairs with chicks were affected by the same environmental factors, mainly anthropogenic, which differed from those affecting the number of fledged chicks per pair. Numbers of fledged chicks per pair was not affected by colony size or by the number of nests with chicks. The categorization of the environmental variables into natural and anthropogenic, in connection with demographic parameters, was relevant to detect factors explaining variation in colony size and breeding parameters. The SOM proved a relevant tool to help determine actual dynamics in White Stork colonies, and thus to support effective conservation decisions at a regional scale
The coordination of cell growth during fission yeast mating requires Ras1-GTP hydrolysis
The spatial and temporal control of polarity is fundamental to the survival of all organisms. Cells define their polarity using highly conserved mechanisms that frequently rely upon the action of small GTPases, such as Ras and Cdc42. Schizosaccharomyces pombe is an ideal system with which to study the control of cell polarity since it grows from defined tips using Cdc42-mediated actin remodeling. Here we have investigated the importance of Ras1-GTPase activity for the coordination of polarized cell growth during fission yeast mating. Following pheromone stimulation, Ras1 regulates both a MAPK cascade and the activity of Cdc42 to enable uni-directional cell growth towards a potential mating partner. Like all GTPases, when bound to GTP, Ras1 adopts an active conformation returning to an inactive state upon GTP-hydrolysis, a process accelerated through interaction with negative regulators such as GAPs. Here we show that, at low levels of pheromone stimulation, loss of negative regulation of Ras1 increases signal transduction via the MAPK cascade. However, at the higher concentrations observed during mating, hyperactive Ras1 mutations promote cell death. We demonstrate that these cells die due to their failure to coordinate active Cdc42 into a single growth zone resulting in disorganized actin deposition and unsustainable elongation from multiple tips. These results provide a striking demonstration that the deactivation stage of Ras signaling is fundamentally important in modulating cell polarity
Impact of facial conformation on canine health: Brachycephalic Obstructive Airway Syndrome
The domestic dog may be the most morphologically diverse terrestrial mammalian species known to man; pedigree dogs are artificially selected for extreme aesthetics dictated by formal Breed Standards, and breed-related disorders linked to conformation are ubiquitous and diverse. Brachycephaly–foreshortening of the facial skeleton–is a discrete mutation that has been selected for in many popular dog breeds e.g. the Bulldog, Pug, and French Bulldog. A chronic, debilitating respiratory syndrome, whereby soft tissue blocks the airways, predominantly affects dogs with this conformation, and thus is labelled Brachycephalic Obstructive Airway Syndrome (BOAS). Despite the name of the syndrome, scientific evidence quantitatively linking brachycephaly with BOAS is lacking, but it could aid efforts to select for healthier conformations. Here we show, in (1) an exploratory study of 700 dogs of diverse breeds and conformations, and (2) a confirmatory study of 154 brachycephalic dogs, that BOAS risk increases sharply in a non-linear manner as relative muzzle length shortens. BOAS only occurred in dogs whose muzzles comprised less than half their cranial lengths. Thicker neck girths also increased BOAS risk in both populations: a risk factor for human sleep apnoea and not previously realised in dogs; and obesity was found to further increase BOAS risk. This study provides evidence that breeding for brachycephaly leads to an increased risk of BOAS in dogs, with risk increasing as the morphology becomes more exaggerated. As such, dog breeders and buyers should be aware of this risk when selecting dogs, and breeding organisations should actively discourage exaggeration of this high-risk conformation in breed standards and the show ring
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