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1.
Am J Bot ; 110(3): 1-21, 2023 03.
Article in English | MEDLINE | ID: mdl-36821420

ABSTRACT

PREMISE: Ficus is a scientifically and economically important genus with abundant fossil records from the Paleocene to Pleistocene, but with an intriguing early evolutionary history that remains unresolved. Here, the foliage of three well-preserved figs is described from the early Paleogene succession of the Gurha mine, Rajasthan, India. These fossils provide new morphological data that strengthens our understanding of the past occurrences of Ficus and, alongside all validly published records of fossil figs, helps to trace the evolutionary history of figs. METHODS: Fossils were identified and described by comparison with their closest modern analogs using the Nearest Living Relative (NLR) technique. Validated fig records are listed and categorized into six geological time frames. Modern precipitation data for the current distributions of NLRs were downloaded from the Climatic Research Unit Timeseries. RESULTS: Fossil leaves assigned to three new species Ficus paleodicranostyla, F. paleovariegata, and F. paleoauriculata closely resemble their modern analogs based on leaf morphology. Reliable fossil records were used to hypothesize historical fig distributions and paleodispersal pathways. Precipitation data suggest higher precipitations at the fossil locality during the early Paleogene than at present. CONCLUSIONS: The fossils described herein supplement fig fossil records known from other regions indicating that figs were widely diverse across low latitudes by the early Paleogene. These data support a Eurasian origin for figs, highlight a pivotal role for the Indian subcontinent during the early phase of fig diversification, and depict a perhumid-to-humid climate with high rainfall concordant with paleoclimate evidence from the Gurha mine.


Subject(s)
Ficus , Wasps , Animals , India , Fossils , Plant Leaves/anatomy & histology , Climate , Phylogeny
2.
Fungal Biol ; 124(11): 958-968, 2020 11.
Article in English | MEDLINE | ID: mdl-33059847

ABSTRACT

Silicified fossil legume woods of Cynometroxylon Chowdhury & Ghosh collected from the Neogene (late Miocene) sediments of the Bengal Basin, eastern India, exhibit fungal decay seldom found in the fossil record. The wood possesses numerous perforate areas on the surface that seem to be the result of extensive fungal activity. In transverse section, the decayed areas (pockets) appear irregular to ellipsoidal in outline; in longitudinal section these areas of disrupted tissue are somewhat spindle-shaped. Individual pockets are randomly scattered throughout the secondary xylem or are restricted to a narrow zone. The aforesaid patterns of decay in fossil wood show similarities with that of white rot decay commonly produced by higher fungi, specifically basidiomycetes and ascomycetes. The host fossil wood harbors abundant ramifying and septate fungal hyphae with knob like swellings similar to pseudoclamps in basidiomycetes, and three-celled conidia-like reproductive structures. This record expands our current knowledge of wood decaying fungi-host plant interaction in the Neogene tropical forests of Peninsular India.


Subject(s)
Basidiomycota , Fabaceae , Fossils , Wood , Fossils/microbiology , India , Wood/microbiology
3.
J Air Waste Manag Assoc ; 70(8): 745-752, 2020 08.
Article in English | MEDLINE | ID: mdl-32401189

ABSTRACT

Investigation of suspect surface contamination in a building may require comparative sampling across different zones to provide meaningful information with regard to contaminant sources, pathways and/or extent of dispersal. However, evaluation of the data using traditional null hypothesis significance testing (NHST) based upon the mean may result in misleading inference when encountering erratic distributions typical of environmental contaminant data. Sampling data (n = 90) for lead content in surface dust collected throughout a historic building with suspect contamination from uncontrolled disturbance to lead coatings were evaluated using traditional NHST and randomization/permutation inference; the latter metric was the maximum difference in frequency of detection (Δfd max), to directly calculate the probability of the observed differences. In the examples for lead in surface dust presented herein, areas with "lower" mean concentration and/or no significant difference via NHST actually represented "greater contamination," as Δfd max indicated a greater probability of encountering lead at higher concentrations. Resulting conclusions with regard to sources and pathways contradicted those generated from traditional NHST, and underscore the need to recognize differences in applicability of different inference approaches, depending upon the distribution of the data and the particular problem. This is particularly relevant for forensic purposes. IMPLICATIONS: The use of permutation/randomization inference to gain insight into sources and pathways of contamination may be more appropriate than the conventional Neyman/Pearson (N/P) logic in negative hypothesis significance testing (NHST). This suggests a broader understanding by environmental professionals of the assumptions and limitations of NHST and alternative inference such as through permutation/randomization is warranted.


Subject(s)
Dust/analysis , Environmental Monitoring/statistics & numerical data , Environmental Pollutants/analysis , Lead/analysis , Environmental Monitoring/methods , Probability
4.
Sci Adv ; 5(3): eaav2189, 2019 03.
Article in English | MEDLINE | ID: mdl-30854430

ABSTRACT

The Late Paleogene surface height and paleoenvironment for the core area of the Qinghai-Tibetan Plateau (QTP) remain critically unresolved. Here, we report the discovery of the youngest well-preserved fossil palm leaves from Tibet. They were recovered from the Late Paleogene (Chattian), ca. 25.5 ± 0.5 million years, paleolake sediments within the Lunpola Basin (32.033°N, 89.767°E), central QTP at a present elevation of 4655 m. The anatomy of palms renders them intrinsically susceptible to freezing, imposing upper bounds on their latitudinal and altitudinal distribution. Combined with model-determined paleoterrestrial lapse rates, this shows that a high plateau cannot have existed in the core of Tibet in the Paleogene. Instead, a deep paleovalley, whose floor was <2.3 km above mean sea level bounded by (>4 km) high mountain systems, formed a topographically highly varied landscape. This finding challenges prevailing views on tectonic processes, monsoon dynamics, and the evolution of Asian biodiversity.


Subject(s)
Fossils , Geography , Tibet
5.
Environ Monit Assess ; 188(3): 147, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26850713

ABSTRACT

Quantitative inference from environmental contaminant data is almost exclusively from within the classic Neyman/Pearson (N/P) hypothesis-testing model, by which the mean serves as the fundamental quantitative measure, but which is constrained by random sampling and the assumption of normality in the data. Permutation/randomization-based inference originally forwarded by R. A. Fisher derives probability directly from the proportion of the occurrences of interest and is not dependent upon the distribution of data or random sampling. Foundationally, the underlying logic and the interpretation of the significance of the two models vary, but inference using either model can often be successfully applied. However, data examples from airborne environmental fungi (mold), asbestos in settled dust, and 1,2,3,4-tetrachlorobenzene (TeCB) in soil demonstrate potentially misleading inference using traditional N/P hypothesis testing based upon means/variance compared to permutation/randomization inference using differences in frequency of detection (Δf d). Bootstrapping and permutation testing, which are extensions of permutation/randomization, confirm calculated p values via Δf d and should be utilized to verify the appropriateness of a given data analysis by either model.


Subject(s)
Environmental Monitoring/methods , Dust , Environment , Probability , Random Allocation , Research Design
8.
J Med Genet ; 46(5): 308-14, 2009 May.
Article in English | MEDLINE | ID: mdl-19188198

ABSTRACT

BACKGROUND: Infantile cardiomyopathy is a genetically heterogeneous disorder with significant morbidity and mortality. METHODS: This study aimed to identify the mutation present in four unrelated patients who presented as infants with isolated hypertrophic cardiomyopathy. RESULTS: In all four, a novel mitochondrial m.8528T-->C mutation was identified. This results in a change of the initiation codon in ATPase 6 to threonine and a concurrent change from a highly conserved hydrophobic amino acid, tryptophan, at position 55 of ATPase 8 to a highly basic arginine. To our knowledge, this is the first report of a mutation affecting both mitochondrial genome-encoded complex V subunit proteins. Testing of the relatives of one patient indicated that the mutation is heteroplasmic and correlated with disease. CONCLUSION: Mitochondrial genome sequencing should be considered in patients with infantile hypertrophic cardiomyopathy.


Subject(s)
Cardiomyopathy, Hypertrophic/genetics , Mitochondrial Proton-Translocating ATPases/genetics , Mutation , Base Sequence , Cardiomyopathy, Hypertrophic/enzymology , Cardiomyopathy, Hypertrophic/pathology , Child , Child, Preschool , DNA Mutational Analysis , Female , Humans , Infant , Infant, Newborn , Male
9.
J Occup Environ Hyg ; 5(2): 85-93, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18075881

ABSTRACT

A number of interpretive descriptors have been proposed for bioaerosol data due to the lack of health-based numerical standards, but very few have been verified as to their ability to describe a suspect indoor environment. Culturable and nonculturable (spore trap) sampling using the bootstrap version of Monte Carlo simulation (BMC) at several sites during 2003-2006 served as a source of indoor and outdoor data to test various criteria with regard to their variability in characterizing an indoor or outdoor environment. The purpose was to gain some insight for the reliability of some of the interpretive criteria in use as well as to demonstrate the utility of BMC methods as a generalized technique for validation of various interpretive criteria for bioaerosols. The ratio of nonphylloplane (NP) fungi (total of Aspergillus and Penicillium) to phylloplane (P) fungi (total of Cladosporium, Alternaria, and Epicoccum), or NP/P, is a descriptor that has been used to identify "dominance" of nonphylloplane fungi (NP/P > 1.0), assumed to be indicative of a problematic indoor environment. However, BMC analysis of spore trap and culturable bioaerosol data using the NP/P ratio identified frequent dominance by nonphylloplane fungi in outdoor air. Similarly, the NP/P descriptor indicated dominance of nonphylloplane fungi in buildings with visible mold growth and/or known water intrusion with a frequency often in the range of 0.5 Fixed numerical criteria for spore trap data of 900 and 1300 spores/m(3) for total spores and 750 Aspergillus/Penicillium spores/m(3) exhibited similar variability, as did ratios of nonphylloplane to total fungi, phylloplane to total fungi, and indoor/outdoor ratios for total fungal spores. Analysis of bioaerosol data by BMC indicates that numerical levels or descriptors based on dominance of certain fungi are unreliable as criteria for characterizing a given environment. The utility of BMC analysis lies in its generalized application to test mathematically the validity of any given descriptor or criterion for bioaerosols, which can be an important tool in quantifying the uncertainty in interpreting bioaerosol data.


Subject(s)
Aerosols/analysis , Air Microbiology , Air Pollution, Indoor/analysis , Monte Carlo Method , Spores, Fungal/isolation & purification , Air Pollutants/analysis , Environmental Monitoring/methods , Fungi/isolation & purification , United States
10.
Clin Genet ; 73(2): 165-70, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18076673

ABSTRACT

Most children do not have a known cause of cardiomyopathy which limits the potential for disease-specific therapies. Of the different phenotypic presentations of cardiomyopathy, the restrictive form carries the poorest prognosis and has the lowest rate of identification of etiology. We present the first description of a beta-myosin heavy chain gene mutation in an infant with restrictive cardiomyopathy requiring cardiac transplantation. As demonstrated by three-dimensional protein structure modeling, the missense mutation is in a highly conserved amino acid at the critical binding region for the essential light chain. This case emphasizes that mutations in sarcomeric proteins, which are known to cause hypertrophic cardiomyopathy in adults, may be associated with the development of restrictive physiology in childhood. Identification of the genetic basis of pediatric cardiomyopathy has important implications for management and genetic counseling.


Subject(s)
Cardiomyopathies/genetics , Heart Murmurs/diagnosis , Myosin Heavy Chains/genetics , Ventricular Myosins/genetics , Adult , Amino Acid Sequence , Cardiomyopathies/surgery , Heart Transplantation , Humans , Infant , Male , Molecular Sequence Data , Sequence Alignment
11.
Inj Prev ; 13(6): 416-21, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18056320

ABSTRACT

OBJECTIVE: To estimate the economic cost of injuries in a population of US high school varsity athletes. DESIGN AND SETTING: The North Carolina High School Athletic Injury Study, conducted from 1996 to 1999, was a prospective cohort study of injury incidence and severity. A two-stage cluster sampling technique was used to select athletic teams from 100 high schools in North Carolina. An injury cost model was used to estimate the economic cost of injury. PARTICIPANTS: Varsity athletes from 12 sports: football, girls' and boy's soccer, girls' and boys' track, girls' and boy's basketball, baseball, softball, wrestling, volleyball, and cheerleading. MAIN OUTCOME MEASURES: Descriptive data were collected at the time of injury. Three types of costs were estimated: medical, human capital (medical costs plus loss of future earnings), and comprehensive (human capital costs plus lost quality of life). RESULTS: The annual statewide estimates were $9.9 million in medical costs, $44.7 million in human capital costs, and $144.6 million in comprehensive costs. The mean medical cost was $709 per injury (95% CI $542 to $927), $2223 per injury (95% CI $1709 to $2893) in human capital costs, and $10,432 per injury (95% CI $8062 to $13,449) in comprehensive costs. Sport and competition division were significant predictors of injury costs. CONCLUSIONS: Injuries among high school athletes represent a significant economic cost to society. Further research should estimate costs in additional populations to begin to develop cost-effective sports injury prevention programs.


Subject(s)
Athletic Injuries/economics , Adolescent , Adult , Athletic Injuries/epidemiology , Cost of Illness , Epidemiologic Methods , Female , Humans , Income , Male , North Carolina/epidemiology , Quality of Life
12.
Plant Cell Environ ; 30(8): 934-43, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17617821

ABSTRACT

Sapwood respiration often declines towards the sapwood/heartwood boundary, but it is not known if parenchyma metabolic activity declines with cell age. We measured sapwood respiration in five temperate species (sapwood age range of 5-64 years) and expressed respiration on a live cell basis by quantifying living parenchyma. We found no effect of parenchyma age on respiration in two conifers (Pinus strobus, Tsuga canadensis), both of which had significant amounts of dead parenchyma in the sapwood. In angiosperms (Acer rubrum, Fraxinus americana, Quercus rubra), both bulk tissue and live cell respiration were reduced by about one-half in the oldest relative to the youngest sapwood, and all sapwood parenchyma remained alive. Conifers and angiosperms had similar bulk tissue respiration despite a smaller proportion of parenchyma in conifers (5% versus 15-25% in angiosperms), such that conifer parenchyma respired at rates about three times those of angiosperms. The fact that 5-year-old parenchyma cells respired at the same rate as 25-year-old cells in conifers suggests that there is no inherent or intrinsic decline in respiration as a result of cellular ageing. In contrast, it is not known whether differences observed in cellular respiration rates of angiosperms are a function of age per se, or whether active regulation of metabolic rate or positional effects (e.g. proximity to resources and/or hormones) could be the cause of reduced respiration in older sapwood.


Subject(s)
Cellular Senescence/physiology , Oxygen/metabolism , Trees/metabolism , Xylem/metabolism , Acer/cytology , Acer/metabolism , Fraxinus/cytology , Fraxinus/metabolism , Pinus/cytology , Pinus/metabolism , Quercus/cytology , Quercus/metabolism , Time Factors , Trees/cytology , Tsuga/cytology , Tsuga/metabolism , Xylem/cytology
13.
Eur J Pediatr Surg ; 17(3): 214-6, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17638164

ABSTRACT

Sacrococcygeal teratoma (SCT) can be sporadic or familial and there appear to be different characteristics to these entities. It can be an isolated anomaly or occur as part of the Currarino triad, when it is associated with anorectal malformations and sacral anomalies. We present a case of familial sacrococcygeal teratoma and discuss its relationship to previously published reports, drawing conclusions regarding embryogenesis, diagnosis, screening and management.


Subject(s)
Coccyx , Sacrum , Spinal Neoplasms/congenital , Teratoma/congenital , Adult , Diagnosis, Differential , Female , Follow-Up Studies , Humans , Infant, Newborn , Pregnancy , Prenatal Diagnosis , Spinal Neoplasms/diagnosis , Spinal Neoplasms/surgery , Teratoma/diagnosis , Teratoma/surgery , Time Factors
14.
Pediatr Cardiol ; 27(3): 336-42, 2006.
Article in English | MEDLINE | ID: mdl-16596434

ABSTRACT

The objective of this study was to evaluate the safety and efficacy of carvedilol in pediatric patients with stable moderate heart failure. We performed a single-arm prospective drug trial at three academic medical centers and the results were compared to historical controls. Patients were 3 months to 17 years old with an ejection fraction <40% in the systemic ventricle for at least 3 months on maximal medical therapy including ACE inhibitors. Treated patients were started on 0.1 mg/kg/day and uptitrated to 0.8 mg/kg/day or the maximal tolerated dose. Echocardiographic parameters of function were prospectively measured at entry and at 6 months. Two composite endpoints were recorded: severe decline in status and significant clinical change. Adverse events were reviewed by a safety committee. Data were also collected from untreated controls with dilated cardiomyopathy meeting entry criteria, assessed over a similar time frame. Twenty patients [12 dilated cardiomyopathy (DCM) and 8 congenital] with a median age of 8.4 years (range, 8 months to 17.8 years) were treated with carvedilol. Three patients discontinued the drug during the study. At entry, there was no statistical difference in age, weight, or ejection fraction between the treated group and controls. The ejection fraction of the treated DCM group improved significantly from entry to 6 months (median, 31 to 40%, p = 0.04), with no significant change in ejection fraction in the control group [median, 29 to 27%, p = not significant (NS)]. The median increase in ejection fraction was larger for the treated DCM group than for the untreated DCM controls (7 vs 0%, p = 0.05). By Kaplan-Meier analysis, time to death or transplant tended to be longer in treated patients (p = 0.07). The difference in the proportion of patients with severe decline in status or significant clinical change in the treated group was not significant compared to the controls (5 vs 12%, p = NS). We conclude that in this prospective protocol of pediatric patients, the use of adjunct carvedilol in the DCM group improved ejection fraction compared to untreated controls and trended toward delaying time to transplant or death.


Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Carbazoles/therapeutic use , Cardiomyopathy, Dilated/physiopathology , Propanolamines/therapeutic use , Stroke Volume/drug effects , Ventricular Dysfunction, Left/drug therapy , Adolescent , Adrenergic beta-Antagonists/pharmacology , Carbazoles/pharmacology , Cardiomyopathy, Dilated/mortality , Cardiomyopathy, Dilated/surgery , Carvedilol , Child , Child, Preschool , Female , Heart Transplantation , Humans , Infant , Male , Propanolamines/pharmacology , Prospective Studies
15.
J Pediatr Surg ; 40(9): 1482-3, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16150353

ABSTRACT

We report a case of a successful surgical resection of a Wilms' tumor in the right kidney with a coincidental preoperative imaging finding of a left-sided inferior vena cava. To our knowledge, these 2 conditions occurring together has not been previously reported in literature. Diagnostic features and the value of magnetic resonance imaging are emphasized. We also review the literature of major venous anomalies and their influence on surgical procedures carried out on such patients.


Subject(s)
Kidney Neoplasms/surgery , Vena Cava, Inferior/abnormalities , Wilms Tumor/surgery , Child , Functional Laterality , Humans , Kidney Neoplasms/pathology , Magnetic Resonance Imaging , Male , Vena Cava, Inferior/pathology , Vena Cava, Inferior/surgery , Wilms Tumor/pathology
16.
Pediatr Cardiol ; 26(6): 768-71, 2005.
Article in English | MEDLINE | ID: mdl-15990951

ABSTRACT

Duchenne muscular dystrophy leads to progressive deterioration in skeletal and cardiac muscle function. Steroids prolong ambulation and improve respiratory muscle strength. The authors hypothesized that steroid treatment would stabilize cardiac muscle function. Echocardiograms performed from 1997 to 2004 for 111 subjects 21 years of age or younger with Duchenne muscular dystrophy were restrospectively reviewed. The medical record was reviewed for steroid treatment. Untreated and steroids-treated subjects did not differ in age, height, weight, body mass index, systolic and diastolic blood pressure, or left ventricular mass. The shortening fraction was lower in the untreated group. Of those treated, 29 received prednisone and 19 received deflazacort. There was no difference in the shortening fraction between the two treated subgroups. Treated subjects not receiving steroids still had a normal shortening fraction, which was no different from the shortening fraction of those still receiving treatment. As compared with the treated subjects, the untreated subjects 10 years of age or younger were 4.4 times more likely to have a shortening fraction less than< 28% (p = 0.03), and the untreated subjects older than 10 years were 15.2 times more likely to have a shortening fraction less than< 28% (p < 0.01). This retrospective study suggests that the progressive decline in cardiac function of patients with Duchenne muscular dystrophy can be altered by steroid treatment. The effect appears to be sustained beyond the duration of treatment and independent of steroid type.


Subject(s)
Glucocorticoids/therapeutic use , Heart/drug effects , Immunosuppressive Agents/therapeutic use , Muscular Dystrophy, Duchenne/drug therapy , Prednisone/therapeutic use , Pregnenediones/therapeutic use , Adolescent , Adult , Age Factors , Child , Child, Preschool , Heart/physiopathology , Humans , Muscular Dystrophy, Duchenne/physiopathology , Retrospective Studies , Time Factors , Ventricular Function, Left/drug effects
17.
Inj Prev ; 11(2): 71-6, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15805434

ABSTRACT

OBJECTIVE: To compare injury case fatality rates in the United States (US) with New Zealand (NZ) to guide future information collection, research, and evaluation. DESIGN: Using NZ (1992-96) and US (1996-98) mortality censuses, NZ national 1992-96 hospital discharge censuses, and US 1996-98 National Hospital Discharge Survey data, the authors compared case fatality rates by mechanism and intent of injury and age group. The analysis was restricted to severe injuries (AIS> or =3). SUBJECTS: NZ (1992-96) and US (1996-98) populations. MAIN OUTCOME MEASURES: Ratio of case fatality rates in NZ versus the US (RCFR(NZ:US)). RESULTS: Overall, among cases meeting the study criteria, unintentional injuries were 1.57 times more likely fatal in NZ and intentional assault injuries were 1.14 times more likely to be fatal in the US. Firearms were involved in 50% of US assaults versus 8% of NZ assaults. By mechanism, cutting/piercing injuries were 1.86, firearm injuries were 1.41, and motor vehicle injuries were 1.44 times more to be likely fatal in NZ. Natural/environmental injuries (RCFR(NZ:US) = 0.57), unintentional poisonings (RCFR(NZ:US) = 0.26), and unintentional suffocations (RCFR(NZ:US) = 0.67) were significantly more likely to be fatal in the US. CONCLUSIONS: Possible reasons for the observed results include: differences in geography and proportion of population in rural areas, trauma system differences, road design and vehicle types, seat belt use, larger role of firearms in US assaults, coding practices, policies, and environmental factors. Disparities evoke hypotheses to test in future research that will guide priority setting and intervention.


Subject(s)
Wounds and Injuries/mortality , Accidents, Traffic , Asphyxia/etiology , Hospitalization , Humans , New Zealand/epidemiology , Poisoning/mortality , United States/epidemiology , Violence , Wounds and Injuries/etiology , Wounds, Gunshot/mortality , Wounds, Stab/mortality
18.
J Occup Environ Hyg ; 2(5): 257-66, 2005 May.
Article in English | MEDLINE | ID: mdl-15814380

ABSTRACT

Culturable airborne fungal spore sampling at five building sites during 2002-2003 provided a bank of outdoor data (102 samples total) to evaluate differences in levels of individual species of airborne fungi during the morning and afternoon hours. A minimum of 15 (outdoor) air samples was collected at each site, and data were segregated into morning (before noon) and afternoon subsets. Significant differences in airborne levels for all detected fungal types between the morning and afternoon subsets were determined for each site, using a direct calculation of probability. Significance was defined by differences in frequency of detection above the combined median (p=0.90 or greater) for the respective fungal type. The levels of various species of fungi in the outdoor air varied significantly between morning and afternoon data sets at all five sites, with no pattern by species, time of day, or location. Levels of Penicillium, Aspergillus, or other fungal species associated with problematic buildings if detected outdoors, can be significantly greater in the morning or afternoon (or exhibit no significant difference) on any given day. The data does not indicate laboratory analysis as a major contributor to the variability exhibited in bioaerosols, and underscores the necessity of collecting sufficient number of samples in the outdoor air in both the morning and afternoon to prevent bias when comparing a suspect indoor environment to outdoor conditions.


Subject(s)
Air Pollutants/analysis , Air Pollutants/standards , Fungi , Models, Theoretical , Aerosols , Data Collection , Environmental Monitoring , Humans , Reference Values , Time Factors
19.
Nature ; 433(7024): 403-6, 2005 Jan 27.
Article in English | MEDLINE | ID: mdl-15674288

ABSTRACT

The range of possibilities for future climate evolution needs to be taken into account when planning climate change mitigation and adaptation strategies. This requires ensembles of multi-decadal simulations to assess both chaotic climate variability and model response uncertainty. Statistical estimates of model response uncertainty, based on observations of recent climate change, admit climate sensitivities--defined as the equilibrium response of global mean temperature to doubling levels of atmospheric carbon dioxide--substantially greater than 5 K. But such strong responses are not used in ranges for future climate change because they have not been seen in general circulation models. Here we present results from the 'climateprediction.net' experiment, the first multi-thousand-member grand ensemble of simulations using a general circulation model and thereby explicitly resolving regional details. We find model versions as realistic as other state-of-the-art climate models but with climate sensitivities ranging from less than 2 K to more than 11 K. Models with such extreme sensitivities are critical for the study of the full range of possible responses of the climate system to rising greenhouse gas levels, and for assessing the risks associated with specific targets for stabilizing these levels.

20.
Inj Prev ; 10(6): 338-43, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15583254

ABSTRACT

OBJECTIVE: To compare availability, urban price, and affordability of child/family safety devices between 18 economically diverse countries. DESIGN: Descriptive: urban price surveys by local safety organisations or shoppers. SETTING: Retail stores and internet vendors. MAIN OUTCOME MEASURES: Prices expressed in US dollars, and affordability measured by hours of factory work needed to buy a child safety seat, a belt-positioning booster seat, a child bicycle helmet, and a smoke alarm. RESULTS: Prices of child and family safety devices varied widely between countries but the variation for child safety seats and bicycle helmets did not relate strongly to country income. Safety devices were expensive, often prohibitively so, in lower income countries. Far more hours of factory work were required to earn a child safety device in lower income than middle income, and middle income than higher income, countries. A bicycle helmet, for example, cost 10 hours of factory work in lower income countries but less than an hour in higher income countries. Smoke alarms and booster seats were not available in many lower income countries. CONCLUSIONS: Bicycles and two-axle motor vehicles were numerous in lower and middle income countries, but corresponding child safety devices were often unaffordable and sometimes not readily available. The apparent market distortions and their causes merit investigation. Advocacy, social marketing, local device production, lowering of tariffs, and mandatory use legislation might stimulate market growth. Arguably, a moral obligation exists to offer subsidies that give all children a fair chance of surviving to adulthood.


Subject(s)
Protective Devices/economics , Wounds and Injuries/prevention & control , Child , Child, Preschool , Costs and Cost Analysis , Head Protective Devices/economics , Head Protective Devices/supply & distribution , Humans , Income , Infant , Infant Equipment/economics , Infant Equipment/supply & distribution , Protective Devices/supply & distribution , Seat Belts/economics , Seat Belts/supply & distribution , Smoke
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