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Historical Data (historical + data)
Selected AbstractsThe Financial Impact of Ambulance Diversions and Patient ElopementsACADEMIC EMERGENCY MEDICINE, Issue 1 2007Thomas Falvo DO Abstract Objectives Admission process delays and other throughput inefficiencies are a leading cause of emergency department (ED) overcrowding, ambulance diversion, and patient elopements. Hospital capacity constraints reduce the number of treatment beds available to provide revenue-generating patient services. The objective of this study was to develop a practical method for quantifying the revenues that are potentially lost as a result of patient elopements and ambulance diversion. Methods Historical data from 62,588 patient visits to the ED of a 450-bed nonprofit community teaching hospital in central Pennsylvania between July 2004 and June 2005 were used to estimate the value of potential patient visits foregone as a result of ambulance diversion and patients leaving the ED without treatment. Results The study hospital may have lost $3,881,506 in net revenue as a result of ambulance diversions and patient elopements from the ED during a 12-month period. Conclusions Significant revenue may be foregone as a result of throughput delays that prevent the ED from utilizing its existing bed capacity for additional patient visits. [source] Is there a higher risk for herbivore outhreaks after cold mast years?ECOGRAPHY, Issue 6 2000An analysis of two plant/herbivore series from southern Norway Historical data on two plant-herbivore interactions from southern Norway were used to test the hypothesis that the degree of herbivore outbreaks in post-mast years is negatively related to summer temperatures in the mast year, because plants are more depressed after a high seed production if temperatures and thus the photosynthetic activity is low. The plant species were the sessile oak Quercus petraea and the bilberry Vaceinium myrtillus. For the former species post-mast years were identified from reports given by the local forest authorities for the period 1930,48, and from acorn export curves for the period 1949,98, For the latter species, post-mast years were identified mainly from bilberry export curves for the period 1920,31, from game reports for the period 1932,78. and from diary notes for the period 1979,87. The herbivore species used were the green oak leaf roller moth Tortrix viridana and the capercaillie Tetrao urogallus. Eight moth outbreaks on oak forests were reported by the forest authorities in the period 1930,98, and they all started in a post-mast year of the sessile oak. There were however also eleven post-mast years without moth outbreaks. According to game reports, observations and autumn counts, all increases in the autumn population size of capercaillie during 1920 88 occurred in or after a year with high bilberry production. Among i8 post-mast years, there were seven with strong increase, seven with slight or moderate increase, and four with no increase. For both herbivore species, post-mast years with marked population increases had significantly lower summer temperatures in the preceding (mast) year than had post-mast years with no or slight increases. For moth populations there also was a negative effect of high temperatures in April, possibly because moth eggs tend to hatch too early relative lo budburst if spring temperatures are high. For the capercaillie, high amount of precipitation in June , July seemed to have some negative impact on the autumn population sizes, as also found in previous studies. [source] Lifetime and baseline alcohol intake and risk of cancer of the upper aero-digestive tract in the European Prospective Investigation into Cancer and Nutrition (EPIC) studyINTERNATIONAL JOURNAL OF CANCER, Issue 2 2009Cornelia Weikert Abstract Recent alcohol consumption is an established risk factor for squamous cell carcinoma (SCC) of the upper aero-digestive tract. In contrast, the role of lifetime exposure to alcohol with regard to risk of SCC is not well established. Historical data on alcohol use are available in 271,253 participants of the European Prospective Investigation into Cancer and Nutrition (EPIC). During 2,330,381 person years, 392 incident SCC cases (279 men and 113 women) were identified. Cox regression was applied to model sex-specific associations between lifetime alcohol intake and SCC risk adjusting for potential confounders including smoking. Compared to men who drank 0.1,6.0 g/day alcohol at lifetime, the relative risks (RR) for developing SCC were significantly increased for men who drank 30.1,60.0 g/day (RR 1.65, 95% confidence interval:1.00,2.71), 60.1,96.0 g/day (RR 2.20, 95%CI 1.23,3.95), and >96.0 g/day, (RR 4.63, 95% CI 2.52,8.48), and for former drinkers (RR 4.14, 95%CI 2.38,7.19). These risk estimates did not considerably change when baseline alcohol intake was analyzed. Compared to women who drank 0.1,6.0 g/day alcohol intake at lifetime, the RR were significantly increased for women who drank >30 g/d (RR 6.05, 95%CI 2.98,12.3). Applying similar categories, the relative risk for baseline alcohol intake was 3.26 (95%CI 1.82,5.87). We observed a stronger association between alcohol intake at lifetime and risk of SCC in women compared to men (p for interaction = 0.045). The strong dose-response relation for lifetime alcohol use underscores that alcohol is an important risk factor of SCC of the upper aero-digestive tract throughout life. © 2009 UICC [source] The use of SST and SOI anomalies as indicators of crop yield variabilityINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 1 2009Maria I. Travasso Abstract Interannual climate variability accounts for most of the observed crop yield fluctuations in the main agricultural region of Argentina. Moreover, in this region climatic variations are related to sea surface temperatures (SST) and the Southern Oscillation Index (SOI). In the present study, we aimed to obtain indicators of crop yield variability based on these drivers. For this purpose, monthly anomalies corresponding to SSTs from the Equatorial Pacific (SSTN3) and South Atlantic (SSTSA) Oceans and the SOI were related to maize, sunflower and soybean grain yield anomalies. Historical data (1923,2000 for maize, 1934,2000 for sunflower and 1969,2000 for soybean) were used to obtain grain yield anomalies at the county level after removing technology trends by smoothing techniques. By means of correlation analysis, we obtained the counties presenting significant association (p < 0.05) between monthly SST/SOI anomalies and yield anomalies, for the period 1950,1997. Those indicators showing spatial consistency were classified in percentiles, and the values corresponding to the upper and lower terciles showed to be useful to discriminate between positive and negative yield anomalies (high and low yields). In general, SOI for maize and SSTSA for soybean and sunflower were the best indicators of crop yield variability. SOI corresponding to September and May were useful in counties contributing to 71% of maize production. SSTa_SA (June) was the best for soybean in the main producing region, which includes 72% of the total production. SSTa_SA (March) could be useful for sunflower in the northern part of the region, which accounts for 27% of the regional production. Copyright © 2008 Royal Meteorological Society [source] Porotic lesions in immature skeletons from Stara Torina, late medieval SerbiaINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 5 2008M. Djuric Abstract Porotic lesions of immature skeletons have been attracting scientific attention for more than a century. These changes have been documented worldwide and are considered to be one of the indicators of health and/or nutritional status of past human populations. These lesions have frequently been referred to as a nutritional stress indicator, a manifestation of iron-deficiency anaemia, and a condition caused by chronic infections. In this study, 327 immature skeletons from the medieval graveyard of Stara Torina (Serbia) were examined for macroscopic signs of four types of porotic lesions: cribra orbitalia, femoral cribra, humeral cribra, and porotic hyperostosis. Femoral cribra was observed in 83.25% of femora, humeral cribra in 58.46% of cases, cribra orbitalia in 46.12% of orbits, while porotic hyperostosis was recorded in only 2.94% of skulls. The majority of skeletons affected by cribra presented symmetrical lesions. Association between all types of cribra was recorded in 33.33% of skeletons. Historical data supported the hypothesis that the investigated population was exposed to frequent infections, especially parasitic ones, which led to the development of porotic bone lesions via several mechanisms: parasite-induced blood loss and diarrhoea (both iron and magnesium malabsorption) or anaemia as a hepcidin-mediated body adaptive response to infection. Copyright © 2008 John Wiley & Sons, Ltd. [source] Barley yellow dwarf viruses (BYDVs) preserved in herbarium specimens illuminate historical disease ecology of invasive and native grassesJOURNAL OF ECOLOGY, Issue 6 2007CAROLYN M. MALMSTROM Summary 1In plant invasion ecology, viruses and other pathogens are often considered in terms of the enemy release hypothesis, which predicts that plants become invasive in new ranges if they escape pathogens from their home range. However, pathogens may sometimes facilitate host spread rather than hinder it. 2Previously, we hypothesized that apparent competition mediated by barley and cereal yellow dwarf viruses (Luteoviridae: BYDVs, CYDVs) may have facilitated historical grassland invasion in California, USA, where Eurasian grasses displaced native grasses in the 18th and 19th centuries (the disease facilitation hypotheses). However, this could have happened only if the viruses were present during the invasion, which is unknown. 3To investigate the historical ecology of BYDVs in California grasses, we analysed preserved virus infections in herbarium specimens and used the historical virus sequences to determine rough time estimates of relevant phylogenetic events. 4The historical viral RNA sequences we identified in invasive and native grasses date from 1917 and are among the oldest recovered from plants thus far and the oldest from North America. 5Herbarium evidence and phylogenetic analysis suggest that BYDVs were likely to have been present in wild grasses during the California grassland invasion and to have shared some functional characteristics with present-day isolates, supporting the disease facilitation hypothesis. 6We found evidence of virus spread from California to Australia (or, less likely, from Australia to California) in the late 19th century, when much horticultural exchange occurred, as well as potential correspondence in the timing of virus diversification events and the beginning of extensive human exchange between the Old and New Worlds. 7Synthesis. Increasing evidence indicates that viruses are important in the ecology of grasslands and may, in some cases, mediate apparent competition among species. Historical data provide essential insight into plant virus ecology and suggest the need to examine human influence on plant virus diversification and spread within natural ecosystems. [source] Society and Housing Form: Home-Centredness in England vs.JOURNAL OF HISTORICAL SOCIOLOGY, Issue 3 2001Family-Centredness in Japan This paper demonstrates some of the ways in which culture affects house form by considering the premise that increased privatised living leads to increased demarcation of private living space. Historical data from England and Japan make it evident that Japanese privatised living was family-centred as compared with English home-centredness, and was reflected in observable differences in the evolution of house forms. While supporting the premise that cultural values influence house forms, the paper concludes that the original framework is too simple, but can be developed to accommodate data from different cultures. [source] Lake Chivero: A management case studyLAKES & RESERVOIRS: RESEARCH AND MANAGEMENT, Issue 2 2003C. H. D. Magadza Abstract Lake Chivero in Zimbabwe was shown to be hypereutrophic. Historical data showed that the eutrophication process had been arrested in the late 1970s. However, a combination of poor planning, multiplicity of jurisdiction, mismatch between rate of urbanization and waste management investment, recent changes in the local climate and a permissive, immature political system that called for no public accountability resulted in environmental management breakdown leading to hypereutrophication of the lake. The case of Lake Chivero is presented as an example of a wider global issue regarding the status of environmental management in competition with other priorities in emerging democracies. [source] Historical data refute recent range contraction as cause of low genetic diversity in isolated frog populationsMOLECULAR ECOLOGY, Issue 2 2004Eric A. Hoffman Abstract This study tested whether low genetic diversity in remnant populations of a declining amphibian is best explained by recent bottlenecks or by a history of being peripheral. We compared diversity from eight microsatellite loci in historical and extant populations from the interior and former periphery of the species' range. We found that historic peripheral populations already had reduced levels of genetic variation before the range contraction. Therefore, low diversity in remnants could not be ascribed to recent range contractions. This study shows that a common conservation strategy for rescuing genetically depauperate populations, artificial gene flow, may often be unwarranted and detrimental to evolutionarily important peripheral populations. [source] Review of anatomy education in Australian and New Zealand medical schoolsANZ JOURNAL OF SURGERY, Issue 4 2010Steven Craig Abstract Anatomy instruction at Australian and New Zealand medical schools has been the subject of considerable debate recently. Many commentators have lamented the gradual devaluation of anatomy as core knowledge in medical courses. To date, much of this debate has been speculative or anecdotal and lacking reliable supporting data. To provide a basis for better understanding and more informed discussion, this study analyses how anatomy is currently taught and assessed in Australian and New Zealand medical schools. A mailed questionnaire survey was sent to each of the 19 Australian and 2 New Zealand medical schools, examining the time allocation, content, delivery and assessment of anatomy for the 2008 academic year. Nineteen of the 21 (90.5%) universities invited to participate completed the survey. There was considerable variability in the time allocation, content, delivery and assessment of anatomy in Australasian medical schools. The average total hours of anatomy teaching for all courses was 171 h (SD ± 116.7, range 56/560). Historical data indicate a major decline in anatomy teaching hours within medical courses in Australia and New Zealand. Our results reveal that as there is no national curriculum for anatomy instruction, the curriculum content, instruction methodology and assessment is highly variable between individual institutions. Such variability in anatomy teaching and assessment raises an important question: is there also variable depth of understanding of anatomy between graduates of different medical courses? [source] The Opportunity Loss of Boarding Admitted Patients in the Emergency DepartmentACADEMIC EMERGENCY MEDICINE, Issue 4 2007Thomas Falvo DO Abstract Objectives: Boarding admitted patients in emergency department (ED) treatment beds has been recognized as a major cause of ED crowding and ambulance diversions. When process delays impede the transfer of admitted patients from the ED to inpatient units, the department's capacity to accept new arrivals and to generate revenue from additional patient services is restricted. The objective of this study was to determine the amount of functional ED treatment capacity that was used to board inpatients during 12 months of operations at a community hospital and to estimate the value of that lost treatment capacity. Methods: Historical data from 62,588 patient visits to the ED of a 450-bed nonprofit community teaching hospital in south central Pennsylvania between July 2004 and June 2005 were used to determine the amount of treatment bed occupancy lost to inpatient holding and the revenue potential of utilizing that blocked production capacity for additional patient visits. Results: Transferring admitted patients from the ED to an inpatient unit within 120 minutes would have increased the functional treatment capacity of the ED by 10,397 hours during the 12 months of this study. By reducing admission process delays, the hospital could potentially have accommodated another 3,175 patient encounters in its existing treatment spaces. Providing emergency services to new patients in ED beds formerly used to board inpatients could have generated $3,960,264 in additional net revenue for the hospital. Conclusions: Significantly higher operational revenues could be generated by reducing output delays that restrict optimal utilization of existing ED treatment capacity. [source] A workflow portal supporting multi-language interoperation and optimizationCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 12 2007Lican Huang Abstract In this paper we present a workflow portal for Grid applications, which supports different workflow languages and workflow optimization. We present an XSLT converter that converts from one workflow language to another and enables the interoperation between different workflow languages. We discuss strategies for choosing the optimal service from several semantically equivalent Web services in a Grid application. The dynamic selection of Web services involves discovering a set of semantically equivalent services by filtering the available services based on metadata, and selecting an optimal service based on real-time data and/or historical data recorded during prior executions. Finally, we describe the framework and implementation of the workflow portal which aggregates different components of the project using Java portlets. Copyright © 2007 John Wiley & Sons, Ltd. [source] The continuing rise of contact dermatitis, Part 2: The scientific journalCONTACT DERMATITIS, Issue 4 2009Derek R. Smith Background: Although citation analysis represents an increasingly common method for examining the performance of scientific journals, few longitudinal studies have been conducted in the specialist fields of dermatology. Objectives: The objective of this study was to provide the first comprehensive bibliometric analysis of Contact Dermatitis for the 30-year period between 1977 and 2006. Materials and Methods: Detailed historical data were extracted from the Thomson Reuters Journal Citation Reports® and systematically analysed. The most highly cited articles published in the journal were also identified and then examined for citation frequency and lag time. Results: Citation analysis showed that the impact factor of Contact Dermatitis has increased significantly over the past 30 years, experiencing a sixfold improvement between 1977 and 2006. Conclusions: Bibliometric trends as identified in the current study clearly demonstrate the ongoing rise of Contact Dermatitis, from early beginnings in the mid-1970s, into the leading scientific periodical we know today. [source] Market-based Price-risk Management for Coffee ProducersDEVELOPMENT POLICY REVIEW, Issue 3 2007Sushil Mohan Coffee is characterised by high levels of price fluctuation, which exposes producers to price risk. Its wide trading in international commodity futures markets offers scope for producers to manage the risk by hedging on these markets, the mechanism for which is based on the use of put options. This article uses historical data of actual put-options contracts to estimate the costs of the mechanism, the benefits being inferred from field evidence. It emerges that the costs are relatively low and outweighed by the benefits for most producers. The article then looks at the operational feasibility of the mechanism for producers and compares it with other hedging mechanisms. [source] Freshwater invasions: using historical data to analyse spreadDIVERSITY AND DISTRIBUTIONS, Issue 1 2007Sarina E. Loo ABSTRACT Aquatic invasive species cause deleterious environmental and economic impacts, and are rapidly spreading through ecosystems worldwide. Despite this, very few data sets exist that describe both the presence and the absence of invaders over long time periods. We have used Geographical Information Systems (GIS) to analyse time-series data describing the spread of the freshwater invasive New Zealand mudsnail, Potamopyrgus antipodarum, in Victoria, Australia, over 110 years. We have mapped the snail's spread, estimated the percentage of stream length invaded through time, calculated the functional form of the spread rate, and investigated the role that the two proposed vectors , fish stocking and angling , have had in this invasion. Since it was first found in 1895, P. antipodarum has expanded its range in Victoria and now occurs throughout much of the southern and central areas of the state. The north of the state is relatively less invaded than the south, with the division corresponding approximately to the presence of the Great Dividing Range. We show that the snail's range has been increasing at an approximately exponential rate and estimate that 20% of total Victorian stream length is currently invaded. We also show that using long-term data can change the outcome of analyses of the relationship between vectors of spread and invasion status of separate catchments. When our time-series data were aggregated through time, the total numbers of fish stocking events and angling activity were both correlated with invasion. However, when the time-series data were used and the number of fish stocking events calculated up until the date of invasion, no relationships with stocking were found. These results underline the role that time-series data, based on both presences and absences, have to play when investigating the spread of invasive species. [source] Spread and current potential distribution of an alien grass, Eragrostis lehmanniana Nees, in the southwestern USA: comparing historical data and ecological niche modelsDIVERSITY AND DISTRIBUTIONS, Issue 5 2006Heather Schussman ABSTRACT The potential distribution of alien species in a novel habitat often is difficult to predict because factors limiting species distributions may be unique to the new locale. Eragrostis lehmanniana is a perennial grass purposely introduced from South Africa to Arizona, USA in the 1930s; by the 1980s, it had doubled its extent. Based on environmental characteristics associated with its introduced and native range, researchers believed that E. lehmanniana had reached the limits of its distribution by the early 1990s. We collected data on E. lehmanniana locations from various land management agencies throughout Arizona and western New Mexico and found new records that indicate that E. lehmanniana has continued to spread. Also, we employed two modelling techniques to determine the current potential distribution and to re-investigate several environmental variables related to distribution. Precipitation and temperature regimes similar to those indicated by past research were the most important variables influencing model output. The potential distribution of E. lehmanniana mapped by both models was 71,843 km2 and covers a large portion of southeastern and central Arizona. Logistic regression (LR) predicted a potential distribution of E. lehmanniana more similar to this species current distribution than GARP based on average temperature, precipitation, and grassland species composition and recorded occurrences. Results of a cross-validation assessment and extrinsic testing showed that the LR model performed as well or better than GARP based on sensitivity, specificity, and kappa indices. [source] Linked electronic medication systems in community pharmacies for preventing pseudoephedrine diversion: A review of international practice and analysis of results in AustraliaDRUG AND ALCOHOL REVIEW, Issue 6 2009CONSTANTINE G. BERBATIS Abstract Introduction and Aims. Pseudoephedrine is a precursor often diverted into the illegal manufacture of amphetamine type substances (ATS). The aim of this study was to evaluate the effectiveness of a linked electronic medication recording system (LEMS) established in Australian pharmacies in 2005 for preventing the diversion of pseudoephedrine. Design and Methods. The number of illegal ATS laboratories detected in each jurisdiction of Australia from 1996,1997 to 2004,2005 were analysed by linear regression nationally and by each jurisdiction. The statistical significance of seizures in 2005,2006 was based on the comparison of the observed value to the 95% prediction confidence intervals calculated from the historical data for each jurisdiction and nationally. Results. Pharmacies in Queensland commenced an LEMS in late 2005 to minimise retail pseudoephedrine diversion. The number of ATS laboratories seized in 2005,2006 in Queensland was significantly lower (P < 0.05) than predicted by historical data. For all other jurisdictions and nationally the totals of laboratories seized in 2005,2006 were not significantly different from predicted values. Discussion and Conclusions. The significant decline in ATS illegal laboratories seized in Queensland in 2005,2006 suggests the effective use of LEMS in pharmacies to minimise pseudoephedrine diversion. In order to evaluate a national LEMS, more frequent data on numbers of linked pharmacies, ATS laboratories seized and indicators of pseudoephedrine sales and misuse are required. Testing the use of LEMS by pharmacies for preventing the diversion of other medicines seems appropriate.[Berbatis CG, Sunderland VB, Dhaliwal SS. Linked electronic medication systems in community pharmacies for preventing pseudoephedrine diversion: A review of international practice and analysis of results in Australia. Drug Alcohol Rev 2009] [source] The termination of the last major phase of aeolian sand movement, coastal dunefields, DenmarkEARTH SURFACE PROCESSES AND LANDFORMS, Issue 7 2006Lars B. Clemmensen Abstract Optically stimulated luminescence (OSL) dating of sand samples from stabilized (or inactive) coastal dunes in Denmark provides information on the age of the termination phase of the last major aeolian activity period. A total of 26 sand samples were taken from four different coastal dunefields around the North Sea, Skagerrak and Kattegat coasts of Denmark. The OSL dates indicate that the last major phase of aeolian activity terminated between ad 1860 and 1905. Most of the dunes examined in this study were active around 1820, during a period documented to have been very stormy. A dune management scheme started around 1792, and this no doubt was a major cause of dunefield stabilization, but an overall decline of storminess, particularly spring and summer storminess, around the end of the 19th century must also have contributed to the increasing inactivity of coastal dunes. The new OSL dates on aeolian sand movement agree well with historical data and data from topographic maps on dune movement. This agreement supports the observation from earlier work that OSL dating of recent aeolian sand movement is accurate over the last few decades to centuries. Copyright © 2005 John Wiley & Sons, Ltd. [source] Contrasting spatial and temporal global change impacts on butterfly species richness during the 20th centuryECOGRAPHY, Issue 6 2006Peter White Regional patterns of species richness are often explained by models using temperature or measures habitat suitability. Generally, species richness is positively associated with temperature, and negatively associated with habitat degradation. While these models have been well tested across spatial scales, they have rarely been tested on a temporal scale , in part due to the difficulty in ascertaining accurate historical data at an appropriate resolution. In this study, we compared the results of temporal and spatial models, each incorporating two predictors of species richness: temperature, and human population density (as a surrogate of human-related habitat impacts). We found that the change in species richness from the early to late part of the 20th century was positively correlated with temperature change, and negatively correlated with human population density change. When we compared these results to two spatial models using contemporary and historic data, the spatial effects of temperature on butterfly richness were similar to its temporal effects, while the effect of human population density through time is the opposite of its spatial effect. More generally, the assumption that spatial patterns are equivalent to temporal ones when applying macroecological data to global change is clearly unreliable. [source] ARGUING OVER [THE] REMOTE CONTROL: WHY INDIGENOUS POLICY NEEDS TO BE BASED ON EVIDENCE AND NOT HYPERBOLEECONOMIC PAPERS: A JOURNAL OF APPLIED ECONOMICS AND POLICY, Issue 1 2007BOYD H. HUNTER Recent public debate on Indigenous issues has been provoked, inter alia, by a 2005 Centre for Independent Studies paper by Helen Hughes and Jenness Warin, who focused on the extent to which policies have been effective in improving the living conditions of Indigenous Australians since the era of self-determination commenced. Unfortunately, the quality of historical data is questionable, and hence we need an appreciation of the reliability of estimates. The 2002 National Aboriginal and Torres Strait Islander Social Survey allows a detailed interrogation of the reliability of estimates. This paper critically analyses socioeconomic changes between 1994 and 2002 for remote and other areas by comparing the recent data with analogous data collected in 1994. Changes in health status and a range of socio-economic indicators are documented to provide a more balanced assessment of the level of economic and social development in the respective areas. [source] Generation of synthetic sequences of half-hourly temperatureENVIRONMETRICS, Issue 8 2008L. Magnano Abstract We present tools to generate synthetic sequences of half-hourly temperatures with similar statistical characteristics to observed historical data. Temperatures are generated using a combination of daily and half-hourly temperature models which account for intra-day and intra-year seasonality, as well as short-and long-term serial correlations. Details of the model estimation are given as well as a description of the synthetic generation. Copyright © 2008 John Wiley & Sons, Ltd. [source] When half of the population died: the epidemic of hemorrhagic fevers of 1576 in MexicoFEMS MICROBIOLOGY LETTERS, Issue 1 2004Rodofo Acuna-Soto Abstract During the 16th century, Mexico suffered a demographic catastrophe with few parallels in world's history. In 1519, the year of the arrival of the Spaniards, the population in Mexico was estimated to be between 15 and 30 million inhabitants. Eighty-one years later, in 1600, only two million remained. Epidemics (smallpox, measles, mumps), together with war, and famine have been considered to be the main causes of this enormous population loss. However, re-evaluation of historical data suggests that approximately 60,70% of the death toll was caused by a series of epidemics of hemorrhagic fevers of unknown origin. In order to estimate the impact of the 1576 epidemic of hemorrhagic fevers on the population we analyzed the historical record and data from the 1570 and 1580 censuses of 157 districts. The results identified several remarkable aspects of this epidemic: First, overall, the population loss for these 157 districts was 51.36%. Second, there was a clear ethnic preference of the disease, the Spanish population was minimally affected whereas native population had high mortality rate. Third, the outbreak originated in the valleys of central Mexico whence it evolved as an expansive wave. Fourth, a positive correlation between altitude and mortality in central Mexico was found. Fifth, a specific climatic sequence of events was associated with the initiation and dissemination of the hemorrhagic fevers. Although the last epidemic of hemorrhagic fevers in Mexico ended in 1815, many questions remain to be answered. Perhaps the most relevant ones are whether there is a possible reemergence of the hemorrhagic fevers and how vulnerable we are to the disease. [source] Unto Every One That Hath Shall Be Given: The Subject Areas Under The HEFCE FormulaFINANCIAL ACCOUNTABILITY & MANAGEMENT, Issue 3 2000Geoffrey Whittington The Higher Education Funding Council for England and Wales (HEFCE) has recently revised its formulae for the distribution of teaching and research funds between universities. The new formulae are intended to increase the transparency of the allocation process and reduce the reliance on historical patterns of allocation. Analysis shows that the coefficients (costs and prices) on which the formulae depend are estimated from historical data, so that reliance on historical patterns has not been eliminated. Moreover, the process by which the coefficients were derived is not transparent and the data used are not necessarily the most appropriate. Thus, the new formulae, which lead to significant shifts in the allocation of funds between subject areas, cannot be shown to have the transparency and sound empirical basis to which HEFCE aspires. [source] Patterns in the spawning of cod (Gadus morhua L.), sole (Solea solea L.) and plaice (Pleuronectes platessa L.) in the Irish Sea as determined by generalized additive modellingFISHERIES OCEANOGRAPHY, Issue 1 2000Eleven ichthyoplankton cruises were undertaken covering most of the Irish Sea during the period February to June, 1995. To identify spawning localities and investigate temporal trends in egg production, the data on stage 1 A egg distributions of cod (Gadus morhua), plaice (Pleuronectes platessa) and sole (Solea solea) have been modelled using generalized additive models (GAMs). A two-stage approach was adopted where presence/absence was firstly modelled as a binary process and a GAM surface subsequently fitted to egg production (conditional on presence). We demonstrate that this approach can be used to model egg production both in space and in time. The spawning sites for cod, plaice and sole in the Irish Sea were defined in terms of the probability of egg occurrence. For cod, we demonstrate that by integrating under predicted egg production surfaces, a cumulative production curve can be generated and used to define percentiles of production and thus delimit the extent of the spawning season. However, for plaice and sole, the surveys did not fully cover the spawning season and the limitations that this imposes on GAM modelling of these data are discussed. Comparison of the spawning sites in 1995 with historical data suggests that the locations of cod, plaice and sole egg production in the Irish Sea have probably remained relatively constant over the last 30 years. [source] Against the Tide: Gendered Prejudice and Disadvantage in EngineeringGENDER, WORK & ORGANISATION, Issue 2 2007Fatma Küskü Although a balance has been achieved in the overall numbers of female and male students in higher education in the industrialized countries, vertical sex segregation has remained high as male academics and students continued to outnumber their female counterparts internationally. Gender representation is only one façade of gendered disadvantage in engineering, as complex forms of gendered disadvantage occur in social, cultural, psychological and economic layers of life, where women engineering students find themselves swimming against the tide of prejudice. This article draws on comparative and historical data, and a qualitative study with interviews and a questionnaire survey which generated 603 completed responses from female and male engineering students in Turkey. It seeks to reveal the complex and layered nature of gendered prejudice levelled against female engineering students. The findings suggest that linear formulations of gendered prejudice and disadvantage in engineering study are insufficient to account for the complexity of influences on career choice and their concomitant gendered outcomes. [source] Soil organic carbon contents in long-term experimental grassland plots in the UK (Palace Leas and Park Grass) have not changed consistently in recent decadesGLOBAL CHANGE BIOLOGY, Issue 7 2009D. W. HOPKINS Abstract A recent report of widespread declines in soil organic C (SOC) in the UK over the 10,25 years until the early 2000s has focussed attention on the importance of resampling previously characterized sites to assess long-term trends in SOC contents and the importance of soils as a potentially volatile and globally significant reservoir of terrestrial C. We have used two sets of long-term experimental plots which have been under constant and known management for over a century and for which historical data exist that allow comparison over recent decades to determine what, if any, changes in SOC content have occurred. The plots used are the Palace Leas (PL) Meadow Hay Plots in north-east England (UK) established in 1897, and from the Park Grass (PG) Continuous Hay experiment established in 1856 at Rothamsted in south-east England. Collectively, these plots represent the only grassland sites in the UK under long-term management where changes in SOC over several decades can be assessed, and are probably unique in the world. The plots have received different manure and fertilizer treatment and have been under known management for at least 100 years. In 1982, total SOC contents were determined for the 0,27 cm layer of six of the PL plots using measurements of SOC concentrations, bulk density and soil depth. In 2006, the same six PL plots were resampled and SOC contents determined again. Four of the plots showed no net change in SOC content, but two plots showed net loss of SOC of 15% and 17% (amounting to decreases of 18 and 15 t C ha,1) since 1982. However, these differences in total SOC content were in a similar range to the variations in bulk density (6,31%) with changing soil water content. In 1959, the soil masses and SOC concentrations to 23 cm depth were measured on six PG plots with fertilizer and manure treatments corresponding closely with those measured on PL. In 2002, the SOC concentrations on the same plots were measured again. On three of the PG plots, SOC concentrations had declined by 2,10%, but in the other three it had increased by 4,8% between 1959 and 2002. If it is assumed that the soil bulk density had not changed over this period, the losses of SOC from the top soils ranged range from 10 to 3 t C ha,1, while the gains ranged from 4 to 7 t C ha,1. When the differences with time in SOC contents for the six PL and the six PG plots were examined using paired t -tests, that is, regarding the plots as two sets of six replicate permanent grasslands, there were no significant differences between 1982 and 2006 for the PL plots or between 1959 and 2002 for the PG plots. Thus, these independent observations on similar plots at PL and PG indicate there has been no consistent decrease in SOC stocks in surface soils under old, permanent grassland in England in recent decades, even though meteorological records for both sites indicate significant warming of the soil and air between 1980 and 2000. Because the potential influences of changes in management or land use have been definitively excluded, and measured rather than derived bulk densities have been used to convert from SOC concentrations to SOC amounts, our observations question whether for permanent grassland in England, losses in SOC in recent decades reported elsewhere can be attributed to widespread environmental change. [source] Model,data synthesis in terrestrial carbon observation: methods, data requirements and data uncertainty specificationsGLOBAL CHANGE BIOLOGY, Issue 3 2005M. R. Raupach Systematic, operational, long-term observations of the terrestrial carbon cycle (including its interactions with water, energy and nutrient cycles and ecosystem dynamics) are important for the prediction and management of climate, water resources, food resources, biodiversity and desertification. To contribute to these goals, a terrestrial carbon observing system requires the synthesis of several kinds of observation into terrestrial biosphere models encompassing the coupled cycles of carbon, water, energy and nutrients. Relevant observations include atmospheric composition (concentrations of CO2 and other gases); remote sensing; flux and process measurements from intensive study sites; in situ vegetation and soil monitoring; weather, climate and hydrological data; and contemporary and historical data on land use, land use change and disturbance (grazing, harvest, clearing, fire). A review of model,data synthesis tools for terrestrial carbon observation identifies ,nonsequential' and ,sequential' approaches as major categories, differing according to whether data are treated all at once or sequentially. The structure underlying both approaches is reviewed, highlighting several basic commonalities in formalism and data requirements. An essential commonality is that for all model,data synthesis problems, both nonsequential and sequential, data uncertainties are as important as data values themselves and have a comparable role in determining the outcome. Given the importance of data uncertainties, there is an urgent need for soundly based uncertainty characterizations for the main kinds of data used in terrestrial carbon observation. The first requirement is a specification of the main properties of the error covariance matrix. As a step towards this goal, semi-quantitative estimates are made of the main properties of the error covariance matrix for four kinds of data essential for terrestrial carbon observation: remote sensing of land surface properties, atmospheric composition measurements, direct flux measurements, and measurements of carbon stores. [source] Temporal dynamics and nestedness of an oceanic island bird faunaGLOBAL ECOLOGY, Issue 4 2006Ermias T. Azeria ABSTRACT Aim, To examine temporal variation in nestedness and whether nestedness patterns predict colonization, extinction and turnover across islands and species. Location, Dahlak Archipelago, Red Sea. Method, The distributions of land birds on 17 islands were recorded in two periods 30 years apart. Species and islands were reordered in the Nestedness Temperature Calculator, software for assessing degrees of nestedness in communities. The occupancy probability of each cell, i.e. species,island combinations, was calculated in the nested matrix and an extinction curve (boundary line) was specified. We tested whether historical and current nested ranks of species and islands were correlated, whether there was a relationship between occupancy probability (based on the historical data) and number of extinctions or colonizations (regression analyses) and whether the boundary line could predict extinctions and colonizations (chi-square analyses). Results, Historical and current nested ranks of islands and species were correlated but changes in occupancy patterns were common, particularly among bird species with intermediate incidence. Extinction and turnover of species were higher for small than large islands, and colonization was negatively related to isolation. As expected, colonizations were more frequent above than below the boundary line. Probability of extinction was highest at intermediate occupancy probability, giving a quadratic relationship between extinction and occupancy probability. Species turnover was related to the historical nested ranks of islands. Colonization was related negatively while extinction and occupancy turnover were related quadratically to historical nested ranks of species. Main conclusions, Some patterns of the temporal dynamics agreed with expectations from nested patterns. However, the accuracy of the predictions may be confounded by regional dynamics and distributions of idiosyncratic, resource-limited species. It is therefore necessary to combine nestedness analysis with adequate knowledge of the causal factors and ecology of targeted species to gain insight into the temporal dynamics of assemblages and for nestedness analyses to be helpful in conservation planning. [source] Predicting risk selection following major changes in medicareHEALTH ECONOMICS, Issue 4 2008Steven D. Pizer Abstract The Medicare Modernization Act of 2003 created several new types of private insurance plans within Medicare, starting in 2006. Some of these plan types previously did not exist in the commercial market and there was great uncertainty about their prospects. In this paper, we show that statistical models and historical data from the Medicare Current Beneficiary Survey can be used to predict the experience of new plan types with reasonable accuracy. This lays the foundation for the analysis of program modifications currently under consideration. We predict market share, risk selection, and stability for the most prominent new plan type, the stand-alone Medicare prescription drug plan (PDP). First, we estimate a model of consumer choice across Medicare insurance plans available in the data. Next, we modify the data to include PDPs and use the model to predict the probability of enrollment for each beneficiary in each plan type. Finally, we calculate mean-adjusted actual spending by plan type. We predict that adverse selection into PDPs will be substantial, but that enrollment and premiums will be stable. Our predictions correspond well to actual experience in 2006. Copyright © 2007 John Wiley & Sons, Ltd. [source] The American Community Survey and Health Insurance Coverage Estimates: Possibilities and Challenges for Health Policy ResearchersHEALTH SERVICES RESEARCH, Issue 2p1 2009Michael Davern Objective. To introduce the American Community Survey (ACS) and its measure of health insurance coverage to researchers and policy makers. Data Sources/Study Setting. We compare the survey designs for the ACS and Current Population Survey (CPS) that measure insurance coverage. Study Design. We describe the ACS and how it will be useful to health policy researchers. Principal Findings. Relative to the CPS, the ACS will provide more precise state and substate estimates of health insurance coverage at a point-in-time. Yet the ACS lacks the historical data and detailed state-specific coverage categories seen in the CPS. Conclusions. The ACS will be a critical new resource for researchers. To use the new data to the best advantage, careful research will be needed to understand its strengths and weaknesses. [source] | ||||||||||||||||||||||||||||||||||||||||||||||