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Earliest Phase (earliest + phase)
Selected AbstractsPatterns of reproductive effort and success in birds: path analyses of long-term data from European ducksJOURNAL OF ANIMAL ECOLOGY, Issue 2 2002Peter Blums Summary 1We tested ecological hypotheses about timing of breeding and reproductive effort in birds, by analysing > 15-year data sets for individually marked females in three species of Latvian ducks (northern shoveler, tufted duck, common pochard). 2Duckling survival and recruitment declined with advancing hatch date in pochard and tufted duck, after controlling for effects of female age and other factors with path analysis, a novel finding which indicates that fitness advantages associated with early hatching extended beyond the prefledging period. Logistic regression analysis suggested further that individual duckling prefledging survival was moderate in the earliest phase of the breeding season, greatest in mid-season and lowest later on. 3However, selection acting against early hatched ducklings was surpassed by strong directional selection favouring recruitment of the earliest hatching females. The absolute and relative numbers of female recruits produced by a breeding female declined sharply with advancing hatch date in all species. 4Unlike previous studies, an hypothesized intraspecific trade-off between duckling mass and brood size was detected, being very robust in two of three species. 5Unexpectedly, female age effects on recruitment were manifested only indirectly by several pathways, the most important being the earlier hatching dates of older females. Size-adjusted body mass (i.e. condition index) was positively related to reproductive success, and was 2,8-fold more influential than female size (indexed by wing length). 6Overall, fecundity-independent variables (e.g. hatching date, weather, indices of duckling production and habitat quality) generally had 2,10 times greater influence on recruitment rates than did fecundity-dependent variables such as female size or condition, duckling mass and brood size, suggesting a critical role for external environmental factors vs. individual female-specific traits in the recruitment process. [source] Pressure,temperature,time evolution of the Central East Greenland Caledonides: quantitative constraints on crustal thickening and synorogenic extensionJOURNAL OF METAMORPHIC GEOLOGY, Issue 9 2003A. P. White Abstract Whereas geologists have known for three-quarters of a century that there was significant crustal thickening in the central East Greenland Caledonides, the crucial role of extensional faulting during Caledonian orogenesis has only been recognized during the past decade. In this paper, new petrographic and thermobarometric observations are presented from migmatitic metasedimentary gneisses of the Forsblad Fjord region (c. 72.5°N). Samples of the Krummedal Sequence, collected from the footwall of the upper of two significant splays of the main extensional fault system in the region,the Fjord Region Detachment (FRD),enable us to establish a relative sequence of metamorphism. Our pressure (P),temperature (T) results imply a clockwise loop in P,T space. As recorded by mineral assemblages in the Krummedal gneisses, prograde metamorphism involved a net increase of c. 4 kbar and 250 °C, with peak conditions of c. 10.5 kbar at 785 °C. Early burial and heating was followed by near-isothermal decompression of 4.5 kbar, a process which is attributed to roughly 18 km of tectonostratigraphic throw on the upper splay of the FRD. Combining data reported here with the published data, it is estimated that the approximate tectonostratigraphic throw along the lower splay of the FRD was c. 16 km. In situ U,Th,Pb-monazite electron microprobe dating suggests that the earliest phase of metamorphism recorded in the Krummedal Sequence gneisses of Forsblad Fjord occurred during the Caledonian orogeny. Furthermore, the combination of our new data with existing conventional TIMS U-Pb and 40Ar/39Ar data imply that: (1) movement along the uppermost splay of the FRD (c. 425,423 Ma) occurred at maximum time-averaged slip-rates equivalent to c. 9 mm of vertical displacement per year; and (2) that the final stages of metamorphism occurred prior to c. 411 Ma, although part of this denudation was likely accommodated on overlying extensional structures that may have been active more recently. There is close agreement between our data and results from the Krummedal Sequence north of the field area (72.5°,74°N), and rocks of the Smallefjord Sequence (75°,76°N) that are suggested to correlate with the Krummedal Sequence. This leads us to infer that the events recorded in the Forsblad Fjord region are of orogen-scale significance. [source] Chondrule thermal history from unequilibrated H chondrites: A transmission and analytical electron microscopy studyMETEORITICS & PLANETARY SCIENCE, Issue 10 2002C. Ferraris Nanotextural and nanochemical data indicate similar thermal evolution for chondrules of the same textural groups; minor, yet meaningful differences occur among the different groups. Olivine is the earliest phase formed and crystallizes between 1500 and 1400 °C. Protoenstatite crystallizes at temperatures higher than 1350,1200 °C; it later inverts to clinoenstatite in the 1250,1200 °C range. Enstatite is surrounded by pigeonitic or (less frequently) augitic rims; the minimal crystallization temperature for the rims is 1000 °C; high pigeonite later inverts to low pigeonite, between 935 and 845 °C. The outer pigeonitic or augitic rims are constantly exsolved, producing sigmoidal augite or enstatite precipitates; sigmoidal precipitates record exsolution temperatures between 1000 and 640 °C. Cooling rate (determined using the speedometer based upon ortho-clinoenstatite intergrowth) was in the order of 50,3000 °C/h at the clinoenstatite-orthoenstatite transition temperature (close to 1250,1200 °C), but decreased to 5,10 °C/h or slower at the exsolution temperature (between 1000 and 650 °C), thus revealing nonlinear cooling paths. Nanoscale observations indicate that the individual chondrules formed and cooled separately from 1500 °C down to at least 650 °C. Accretion into chondritic parent body occurred at temperatures lower than 650 °C. [source] Homogeneity of active demyelinating lesions in established multiple sclerosisANNALS OF NEUROLOGY, Issue 1 2008Esther C. W. Breij PhD Objective Four different patterns of demyelination have been described in active demyelinating lesions of multiple sclerosis (MS) patients that were biopsied shortly after disease onset. These patterns were suggested to represent heterogeneity of the underlying pathogenesis. The aim of this study was to determine whether lesion heterogeneity also exists in an unselected collection of autopsy material from patients with established MS. Methods All MS brain tissue available in the VU Medical Center was assessed for the presence of active demyelinating lesions using magnetic resonance imaging,guided sampling and immunohistochemistry. Tissue blocks containing active demyelinating lesions were evaluated for the presence of complement and antibody deposition, oligodendrocyte apoptosis, differential loss of myelin proteins, and hypoxia-like damage using histology, immunohistochemistry, and confocal microscopy. Blocks with active demyelinating lesions were compared with blocks with active (nondemyelinating) and inactive lesions. Results Complement and antibodies were consistently associated with macrophages in areas of active demyelination. Preferential loss of myelin proteins, extensive hypoxia-like damage, and oligodendrocyte apoptosis were absent or rare. This pattern was observed in all tissue blocks containing active demyelinating lesions; lesion heterogeneity between patients was not found. Interpretation The immunopathological appearance of active demyelinating lesions in established MS is uniform. Initial heterogeneity of demyelinating lesions in the earliest phase of MS lesion formation may disappear over time as different pathways converge in one general mechanism of demyelination. Consistent presence of complement, antibodies, and Fc, receptors in phagocytic macrophages suggests that antibody- and complement-mediated myelin phagocytosis is the dominant mechanism of demyelination in established MS. Ann Neurol 2008;63:16,25 [source] Patient versus informant reported quality of life in the earliest phases of Alzheimer's diseaseINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 12 2006Asmus Vogel Abstract Objectives The study investigated if patient and informant reported Quality of Life (QoL) differed in early Alzheimer's disease (AD). In addition, we examined whether anosognosia had an impact on the agreement between patient and informant ratings of QoL and whether anosognosia, dementia severity, depression and behavioural symptoms were significantly correlated to QoL in early AD. Methods From a prospective research program including newly referred patients (age >60 years and MMSE,,,20), 48 patients with very early AD were included. QoL was assessed using the QoL-AD and EQ-5D scales. Anosognosia was rated on a categorical scale by an examiner. MMSE, Geriatric Depression Scale, Danish Adult Reading Test and Frontal Behavioural Inventory were also administered. Results On most QoL measures patients rated their QoL higher than their informants. Anosognosia was not associated with QoL but significantly with an inverse impact on the agreement between patient and informant ratings of QoL. Self-reported QoL was significantly correlated to depression but not to age, dementia severity, behavioural symptoms or memory impairment. Informant ratings of QoL were significantly correlated to behavioural symptoms and informant ratings on the EQ-5D Visual Analogue Scale were significantly correlated to patient reported depression. Conclusion Patients with early AD generally reported higher QoL than their informants. This disagreement was associated with the presence of anosognosia. Self-reported QoL did not correlate with the MMSE score. Behavioural changes and depressive symptoms may be associated with low QoL. Copyright © 2006 John Wiley & Sons, Ltd. [source] Prevalence rates of spondylolysis in British skeletal populationsINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 3 2005L. Fibiger Abstract As an activity-related pathological lesion, spondylolysis and its prevalence rates are indicative of relative diachronic activity levels in different populations. In this paper we document the prevalence of spondylolytic defects in a series of time-successive populations with special reference to the recording methods employed, and compare the findings with modern clinical studies. We identify epidemiological trends in expression of the condition through 1500 years in a series of skeletonised human remains from England. This includes a 5th,6th-century settlement, a 15th-century mass grave, a 14th to 17th-century rural parish, a medieval Dominican friary, a medieval leper hospital and an 18th to 19th-century crypt collection. These skeletal populations sample human groups experiencing considerable social change from an agrarian, non-centralised early medieval period through the development of the medieval state to the earliest phases of industrialisation in England. A detailed study of all lumbar vertebrae in one of the assemblages highlights discrepancies between clinical prevalence rates for spondylolysis established through radiography, and those resulting from direct osteological analysis of the lumbar region of the vertebral column. Current prevalence rates cited in the osteological as well as the clinical literature are greatly dependent upon the recording methods employed, and the effects of several methods for osteological remains are considered in this treatment. For the populations reported on here, prevalence rates vary from considerably less than 1% to as much as 12%, depending on the method selected. A standardised recording method for spondylolytic lesions is suggested to facilitate accurate prevalence reporting and comparison of activity levels between different populations. Copyright © 2005 John Wiley & Sons, Ltd. [source] Resistance to alien rule in Taiwan and Korea,NATIONS AND NATIONALISM, Issue 1 2009MICHAEL HECHTER ABSTRACT. Although alien rule is widely assumed to be illegitimate, nationalist resistance to it varies across time and space. This article explores why there was greater nationalist resistance to Japanese colonial rule in Korea than Taiwan from the turn of the twentieth century to the end of World War II. Resistance to alien rulers requires both a supply of participants in nationalist collective action and a demand for national self-determination. The article assesses two principal propositions: (1) that the supply of participants increases to the degree that native elites are stripped of their traditional authority and offered few incentives to collaborate; and (2) that the demand for national self-determination decreases to the degree that alien rule is fair and effective. A comparative analysis of the effects of Japanese alien rule in Taiwan and Korea suggests that nationalist resistance is greater in the earliest phases of occupation, that the greater native elites' opportunities, the weaker the resistance to alien rule; and that the fairer the governance, the weaker the resistance to alien rule. [source] Alpine flora dynamics , a critical review of responses to climate change in the Swedish Scandes since the early 1950sNORDIC JOURNAL OF BOTANY, Issue 4 2010Leif Kullman Reports about changes of alpine plant species richness over the past 60 years in the Swedish Scandes are reviewed, synthesized and updated with data from recent reinventories. Methodologically, this endeavour is based on resurveys of the floristic composition on the uppermost 20 m of four high-mountain summits. The key finding is that the species pool has increased by 60,170% since the 1950s and later. Some of the invading species are new to the alpine tundra, with more silvine and thermophilic properties than the extant alpine flora. Not a single species of the original flora has disappeared from any of the summits. This circumstance is discussed in perspective of widespread expectations of pending temperature-driven extinction of alpine species in an alleged future warmer climate. These progressive changes coincided with distinct warming (summer and winter) since the late 1980s. During a short cooler period (1974,1994), the species numbers decreased and the upper elevational limits of some ground cover species descended. Thus, discernible responses, concurrent with both warming and cooling intervals, sustain a strong causal link between climate variability and alpine plant species richness. Methodologically, plot-less revisitation studies of the present kind are beset with substantial uncertainties, which may overstate floristic changes over time. However, it is argued here that carefully executed and critically interpreted, no other method can equally effectively sense the earliest phases of plant invasions into alpine vegetation. [source] | ||||||||||||||||