bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of Melastomataceae and pteridophytes for revealing phytogeographical patterns in Amazonian rain forests
Authors: Ruokolainen Kalle , Linna Ari , Tuomisto Hanna
Published: July 2009

Similarities and differences among eight upland rain forest sites in Peruvian Amazonia were measured separately by using Melastomataceae, pteridophyte and tree species compositions and edaphic characteristics of the sites. All three plant groups showed a similar pattern among the sites, and this pattern could be explained by edaphic differences but not by geographical distances among the sites. The explicability of site-specific edaphic characteristics on the basis of geological history is discussed. The results suggest that both pteridophytes and Melastomataceae can be used as indicators of floristically different rain forest types that are edaphically defined. Distribution patterns of these plant groups can be studied much more rapidly than the patterns of trees and therefore both Melastomataceae and pteridophytes may be used in large scale phytogeographical studies that are urgently needed in the face of rapidly advancing deforestation.
Spatial distribution, fruit production and seed removal of a rare, dioecious canopy tree species (Aglaia aff. flavida Merr. et Perr.) in Papua New Guinea
Authors: Mack Andrew L.
Published: July 2009

All mature individuals of Aglaia aff. flavida (Meliaceae) were mapped in a 260 ha study area at the Crater Mountain Biological Research Station in Papua New Guinea. Sixty-four reproductively mature trees were found in an aggregated distribution with a mean inter-tree distance of 88.9 m. The sample consisted of 35 female and 29 male trees with a mean shortest distance between sexes of 232 m. Seed production and seed removal of 22 female trees was monitored throughout the 1992 fruiting season. Female trees with in 200 m of male trees generally produced large seeds crops (> 100 seeds) whereas trees farther than 200 m from the nearest male had small seed crops (< 100 seeds) regardless of female size (DBH). Most seeds (63.2%, n = 3312) produced in a sub-sample of 22 trees came from the five most fecund trees, which also produced 74.1% of the seeds that were removed by vertebrate dispersers. Where a minority of a population of rare tropical trees produce the majority of progeny, sustainable harvest practices would be most effective where highly fecund individuals are identified and conserved.
Mineral nutrition and die-back inTerminalia ivorensisA. Chev. in Ghana
Authors: Agyeman Victor K. , Safo E. Y.
Published: July 2009

This investigation examined the hypothesis that nutrient deficiency is related to the die-back ofTerminalia ivorensis. The study was conducted on three major soil groups in natural forest andT. ivorensisplantations. Five soil chemical factors, Total nitrogen, organic carbon, effective CEC, exchangeable calcium and magnesium, were positively related to die-back. Foliar nitrogen concentrations in trees suffering from die-back were almost 50% of those of healthy trees. The concentrations of magnesium in the leaves ofT. ivorensisexperiencing die-back were also low. Conversely, high concentrations of foliar calcium were associated with trees under stress. A highly significant relationship was observed between die-back ranks and leaf size.
Standing biomass and carbon distribution in a papyrus (Cyperus papyrus L.) swamp on Lake Naivasha, Kenya
Authors: Jones Michael B. , Muthuri Francis M.
Published: July 2009

The standing live biomass of papyrus swamps is high compared with most other communities dominated by herbaceous vegetation. For the first time, measurements of below-ground rhizome and root biomass are reported here, in addition to measurements of shoot biomass, for a papyrus swamp located on Lake Naivasha, Kenya. The ratio of rhizome and root to shoot dry weight was 1.38: 1 and the total standing live biomass was 7.8 kg(dry weight) m−2. Detritus, formed from slowly decomposing papyrus, is normally the most important sink for carbon in this ecosystem. The amount of detritus retained by swamps varies but at L. Naivasha it contained almost 20 times the carbon found in living biomass. The net primary production of the swamp was calculated to be 6.28 kg(dry weight) m−2 y−1, which is amongst the highest recorded productivities for natural ecosystems. Model estimates of carbon input into the system from photosynthesis are incorporated into a carbon flow diagram for the swamp and this emphasises the importance of detritus as a sink for carbon in this ecosystem.
Chemistry of bulk precipitation in southwestern Viti Levu, Fiji
Authors: Waterloo M. J. , Schelleken J. , Bruijnzeel L. A. , Vugts H. F. , Assenberg P. N. , Rawaqa T. T.
Published: July 2009

The amounts and chemical composition of bulk precipitation were investigated over a continuous 21-mo period (January 1990 to September 1991) at four sites along an East-West transect perpendicular to the coast of Southwest Viti Levu, Fiji. Measured rainfall totals in 1990 ranged from 1796 mm at the coastal Korokula station to 2113 mm at the inland Tulasewa station, which is somewhat higher than the long-term average of 1707 mm at a reference weather station located in the centre of the study area. The first 9 mo of 1991 were relatively dry (range 1027–1533 mm) with a total of 1157 mm at the reference site as compared to a long-term average of 1330 mm. Concentrations of all investigated constituents in bulk rainfall were low, except during the passage of cyclone Sina due to the deposition of large amounts of, especially, chloride, sodium and sulphate in sea spray. Concentrations of sodium and magnesium could be explained fully by maritime contributions to the rainfall composition at all sites. Maritime contributions to the concentrations of calcium, sulphate and potassium accounted for 10–40% of the total, whereas bicarbonate, ammonium, nitrate, silicon, aluminium, iron and manganese were derived exclusively from terrestrial sources. The annual atmospheric nutrient deposition rates were low by pan-tropical standards, particularly when the contribution of cyclone Sina was excluded. Annual totals (in kg ha−1) ranged from 2.4–8.8 for nitrogen, 0.4–1.1 for phosphorus, 2.3–4.9 for potassium, 1.4–1.9 for calcium and from 1.1–1.3 for magnesium. The inclusion of the contribution by the cyclone more than doubled the deposition of potassium, calcium and magnesium, although values still remained well within the range reported for humid tropical areas. The estimated atmospheric deposition of nutrients over a typical rotation period (16 y) was sufficient to balance losses in harvestedPinus caribaealogs (stemwood plus bark) of potassium, calcium and magnesium, but not of nitrogen and, probably, phosphorus. Nutrient losses associated with the harvesting of stemwood alone were compensated entirely by the atmospheric inputs.
Flowering phenology and flower predation of Cullenia exarillata (Bombacaceae) by arboreal vertebrates in Western Ghats, India
Authors: Ganesh T. , Davidar Priya
Published: July 2009

The flowering phenology and flower predation of Cullenia exarillata, a canopy tree at Kakachi in the southern Western Ghats, India, was studied from 1991 to 1993 in relation to general phenological patterns at the community level. Flowering was monitored from 30 marked trees and flower predation estimated from fallen flowers in 40, 1 m2 nets placed under the trees. Flowering occurs in the dry season and coincides with the period of fruit scarcity in the forest. Flowering is synchronous in the population and each tree produces a mean of c. 8730 flowers per tree over a period of c. 47 d. Flowers produced little nectar but the edible fleshy sepals compensated for this. Six species of arboreal mammals and seven species of birds ate the flowers. These consumed 57% of the flower crop of which 37% were completely destroyed. Flower predators could be important in flower fertilization. The overabundance of the flower crop and the timing of flowering, may have evolved as a strategy to satiate predators and enable the flowers to be pollinated during the annual period of fruit scarcity in the forest. This in turn makes Cullenia exarillata a possible keystone species in this forest.
Pre-dispersal and early post-dispersal demography, and reproductive litter production, in the tropical treeDicymbe altsoniiin Guyana
Authors: Zagt Roderick J.
Published: July 2009

The demographic history of a flower-cohort of the tropical treeDicymbe altsonii(Caesalpiniaceae) was studied by collecting litter from flowers, fruits and seeds, and by monitoring seedling survival. Flower production was estimated at 137 to 172 m−2in a plot of 1 ha. Four percent of the flowers yielded a pod, which contained an average of 2.0 seeds. Post-dispersal mortality over 3 mo was 39% of the initial number of dispersed seeds. Most flowers and fruits were aborted. Insect and vertebrate predation in the tree and on the ground was very low. Reproductive litter production of this species was estimated to be equal to leaf litter production. The amount of phosphorus lost in litter from fruits and flowers was much larger than in leaf litter. This implies that the impact of the biennial flowering events on the nutrient dynamics of the trees and of the ecosystem may be large. It is argued that the reproductive cycle and the pre-dispersal demography ofDicymbeseem to be determined by a scarcity of nutrient resources, and possibly by pollinator limitation.
Impact of Hurricane Iniki on native Hawaiian Acacia koa forests: damage and two-year recovery
Authors: Harrington Robin A. , Fownes James H. , Scowcroft Paul G. , Vann Cheryl S.
Published: July 2009

Damage to Hawaiian Acacia koa forest by Hurricane Iniki was assessed by comparison with our previous measures of stand structure and leaf area index (LAI) at sites along a precipitation/elevation gradient on western Kauai. Reductions in LAI ranged from 29 to 80% and were correlated with pre-hurricane LAI and canopy height. The canopy damage resulted in a large pulse of litter, ranging from 4 to 19 t ha-1 across our study sites. In the first year post-hurricane, LAI recovery and relative increase in stand basal area were negatively correlated with the fraction of canopy LAI lost. The two major overstorey species, A. koa and Metrosiderous polymorpha, were damaged less than the sub-canopy species, Dodonaea viscosa and Psidium guajava. Although D. viscosa and P. guajava were both severely damaged in the hurricane, the alien species P. guajava had much higher survival than the native D. viscosa, both as adults and as seedlings. However, seedling density of P. guajava was limited by low recruitment. At these sites, there was no drastic change in species composition following hurricane disturbance, and forest structure and productivity had recovered to a great degree within 2 y.
Seed dispersal and predation in two populations ofCabralea canjerana(Meliaceae) in the Atlantic Forest of southeastern Brazil
Authors: Pizo Marco Aurélio
Published: July 2009

The seed dispersal system of a neotropical tree,Cabralea canjerana(Meliaceae), was studied in two forested areas in southeastern Brazil. The first study site, Parque Estadual Intervales (PEI), is a 49,000-ha reserve composed mostly of old-growth Atlantic rain forest. The second site, Mata de Santa Genebra (MSG), is a 250-ha fragment of old-secondary semideciduous forest whose present bird fauna differs markedly from the original, in part as a consequence of forest fragmentation. At PEI 35 bird species ate the diaspores ofC. canjerana. Black-tailed tityra (Tityra cayana, Tyrannidae) was the main seed disperser, but several other species were also important seed dispersers. In contrast, at MSGC. canjeranadiaspores were eaten by 14 bird species. At this area, the red-eyed vireo (Vireo olivaceus, Vireonidae) was the most important seed disperser, but it was also a ‘waster’ which dropped seeds beneath parent plants, or carried them to sites unsuitable for germination. At PEI, exposed seeds on the forest floor were heavily preyed upon by rodents and insects. Insects destroyed mainly seeds deposited near to parent plants. Insect predation was less intense at MSG than at PEI. The rodent density at MSG was unusually small, and part of the post-dispersal seed predation may be done by terrestrial birds, such as doves and tinamous, which are especially common at MSG. Some of the differences recorded between the seed dispersal systems ofC. canjeranaat PEI and MSG may have been the result of the fragmentation and isolation of the latter area.
A test of the Janzen-Connell model with two common tree species in Amazonian forest
Authors: Cintra Renato
Published: July 2009

Field experiments and survival analysis were used to test whether the Janzen-Connell model operated for two common Amazonian tree species in Peru: the midstorey palm,Astrocaryum murumuru, and the canopy-emergent legume,Dipteryx micrantha. Seed and seedling survival patterns of these species partially supported the model, depending on tree species, type of predator, spatial scale and the particular year. At a small scale of a 2.5-ha plot,Astrocaryumseed predation by insects and mammals was density-dependent. At a larger scale of 100 ha,Dipteryxseed survival increased with distance from conspecific adults, but forAstrocaryumseeds there was no distance dependence. At the scale of 200–400 haDipteryxseed survival was negatively related to the number of individuals present in groups of conspecific adult trees. In 1992 a higher proportion ofAstrocaryumseedlings survived far from, compared with close to, conspecific adult trees, whilst in 1993 moreDipteryxseedlings survived beneath conspecific adult trees than farther away.
Soil seed bank community dynamics in seasonally moist lowland tropical forest, Panama
Authors: Dalling J. W. , Swaine M. D. , Garwood Nancy C.
Published: July 2009

Seasonal changes in the densities of dormant seeds in the soil around eight pioneer trees in the 50-ha Forest Dynamics Plot, on Barro Colorado Island, Panamá were studied, and how seed dispersal and seed dormancy influenced patterns of seed abundance and distribution were examined. Twenty-four, 3-cm-deep soil samples were collected on 30 m transects radiating out from each of the trees in each of four time-intervals through the year, and four 21-cm-deep samples were collected beneath the focal tree crowns. In the surface 0–3 cm of soil, germinable seed densities of all species combined declined from a peak of 1090 seeds m−2in the mid-wet season in August, to 330 seeds m−2by the end of the wet season in November. In contrast, at soil depths >3 cm, there was little variation in soil seed bank density through the year. Some variation in soil seed bank density for individual species could be accounted for by distance to reproductive conspecifics. Among species, abundance in the soil was negatively correlated with seed size. Seed persistence varied greatly among species at this site; after 1 y of burial in mesh bags, seed germinability of four species was near zero, while four other species showed no consistent decline in seed germinability after >2 y of burial. For at least one species,Trema micrantha, prolonged seed dormancy was also possible under natural conditions. Twenty-five percent ofTremaseeds extracted from the soil at a site occupied by an isolatedTrematree that died between 1982 and 1985 were still germinable in 1994.
Annual foraging of the leaf-cutting antAtta colombicain a semideciduous rain forest in Panama
Authors: Wirth Rainer , Beyschlag Wolfram , Ryel Ronald J. , Hölldobler Bert
Published: July 2009

In a 1-y study of vegetation harvested by the leaf-cutting ants,Atta colombicaGuérin, daily harvesting activity of two nests was observed for 24 h atc.1-wk intervals (colony I: June 1993-June 1994; colony II: February-June 1994) on Barro Colorado Island. The average daily quantity of green leaves harvested by colony I was higher during the wet season (11.4 m2d−1) than during the dry season (9.0 m2d−1), but was highly variable between survey days. Total annual herbivory of green leaves was estimated to be 3,855 m2foliage area for colony I and 1,707 m2for colony II. Total dry weight of biomass harvested was higher in the dry season because most material collected during the wet season consisted of green leaves, while during the dry season, more than 50% of the total collected biomass was non-green plant material (stipules ofFicussp., fruits, seeds, and flower parts of a variety of other species) which representedc.one third (111 kg y−1) of the total annual intake (370 kg y−1) of plant material. Total daily biomass intake was negatively correlated with daytime rainfall. The peak of daily foraging was affected by timing and duration of rainfall events. Highest input rates normally occurred between 15:00 and 16:00 h (colony I).Dry weight and surface area of harvested leaf fragments differed between plant species, with thicker leaves generally being cut into smaller pieces. Significant linear correlations were found between total daily harvest of fragments and the respective harvesting rate at the maximum of daily activity. High correspondence was found between estimates using this relationship and the measured daily leaf harvest of four otherAttacolonies and of two colonies reported in published literature. The use of this relationship as a research tool is discussed.
Peoecological evidence ofRaphiain the Pre-Columbian Neotropics
Authors: Urquhart Gerald R.
Published: July 2009

Disjunctions between Africa and the Neotropics present a puzzle that is key to understanding the biogeography of the diverse floras and faunas of both continents. Many authors have proposed thatRaphia taedigeraMaur., the sole Neotropical representative of an otherwise African genus, has been introduced to the New World. Paleoecological data from a freshwater swamp in Nicaragua, which yieldedR. taedigerapollen dating to 2800 ± 90 y before present (BP) andRaphiaseed fragments from 2040 ± 60 BP are presented. These illustrate thatRaphia taedigeraarrived in the New World before trans-Atlantic trade by humans and thus arrived as a result of a natural phenomenon. The lack of differentiation ofR. taedigerafrom the African sister taxon,R. vinifera, suggests recent separation of the two species (i.e. after the creation of the southern Atlantic Ocean by the splitting of West Gondwana). Other evidence supports dispersal ofRaphiaby ocean currents. The palm probably arrived from Africa by floating as an individual fruit or on a raft of vegetation. Thus,R. taedigerarepresents another example of trans-Atlantic dispersal, strengthening the link between the flora and fauna of Africa and the Neotropics.
Germination ecology of forest species from the highlands of Ethiopia
Authors: Teketay Demel , Granström Anders
Published: July 2009

A comparative study of seed germination was performed on 25 species of trees, shrubs, woody climbers and herbs from the dry Afromontane forest zone of Ethiopia. Despite the restricted geographical range of the species tested, the optimum constant temperature for germination varied considerably. For 17 of the species studied, it was between 20 and 25 °C while for three, germination was highest at 30 °C Germination was virtually inhibited (<20%) for eight of the species at 10 °C and eight of the species at 30 °C. There was no clear division in temperature response between plants differing in habitat. For four out of 12 species tested, fluctuating temperatures (20/12 °C) resulted in significantly higher germination than the constant temperature treatment (20 °C), suggesting that field-germination would be favoured by disturbance to the canopy or soil. Speed of germination was negatively correlated with the logarithum of seed size. Most species lay in the range 3–15 d to reach 50% of final germination at their optimum temperature for germination. Germination was significantly suppressed in darkness for a large number of species, particularly for those with seed size less than c. 3 mg. When these were incubated under leaf-filtered light, germination was in most cases even more effectively suppressed. Most of these species are known to have large soil seed banks. Mechanical scarification improved germination over the control in nine species. Five of these also reponded to heat or sulphuric acid scarification. Circumstantial evidence suggests that the species showing heat-induced germination may be fire adapted, although fire is probably a rare natural phenomenon in the Afromontane forest proper. Only one species, Bersama abyssinica, showed a classic recalcitrant behaviour. Germination dropped from 88% when the seeds were fresh to less than 20% after 1 mo of dry storage and 0% after 3 mo. Germinability of seeds of Ekebergia capensis also declined significantly with increasing storage time, although less rapidly; after 24 mo of dry storage, germination was 4%. In contrast, germinability of Juniperus procera was not significantly altered during 54 mo of storage. The results indicate that dormancy plays a major role in regulating germination in dry Afromontane species. Out of the 25 species studied, 15 (60%) showed some degree of initial dormancy. In most of the species with initially non-dormant seeds, dormancy would evidently be induced if the seeds are dispersed under a closed forest canopy or buried in the soil. These patterns of dormancy may have evolved in response to a highly unpredictable climate and small-scale disturbances, and should make the Afromontane forest flora relatively resilent also to anthropogenic disturbances.
Estimating the ages of successional stands of tropical trees from growth increments
Authors: Terborgh John , Flores N. Cesar , Mueller Peter , Davenport Lisa
Published: July 2009

Inability to age tropical trees has imposed major limitations on the basic and applied science of tropical forests. Here advantage was taken of even-aged stands present in successional chronosequences found on Amazonian Whitewater river meanders to simplify the assumptions needed to estimate tree ages from growth measurements. Growth increments of eight common early successional species were measured in 21 0.5-ha plots evenly distributed over chronosequences from the earliest post-pioneer stage to mature Ficus-Cedrela stands representing approximately the mid-point of primary succession. Increment measurements, based on 4 or 5 y of growth, were arrayed in scatter diagrams against the midpoints of the growth intervals. A loess regression of the points, weighted for the higher mortality of slow-growing individuals, was then conducted to generate a ‘best estimate lifetime growth trajectory’ (BELGT) of a ‘typical’ individual surviving to maturity. The BELGT curves were integrated to generate a set of derived curves describing the time required by a ‘typical’ surviving individual to attain any given size up to the maximum for the species. Predictions of the ages of particular stands were derived from these latter curves and found to agree within 3 to 20% of ages independently estimated from the rate of point bar accretion.
Genetic diversity of PhilippineRubus moluccanusL. (Rosaceae) populations examined with VNTR DNA probes
Authors: Busemeyer Daniel T. , Pelikan Stephan , Kennedy Robert S. , Rogstad Steven H.
Published: July 2009

Two synthetic DNA probes composed of tandemly repeated ‘core’ sequences (GACA and GATA) were used to examine genetic diversity at multiple variable-number-tandem-repeat (VNTR) loci within and among four spatially isolated Philippine populations ofRubus moluccanusL. (Rosaceae), an uncultivated bramble widely distributed throughout southeast Asia – Malesia. Central goals were to determine whether apomictic propagation was detectable inR. moluccanusand to examine whether populations isolated on separate islands, or on mountain tops on a single island, were genetically differentiated. Sampling 22 individuals per population, the findings include: (1) no two individuals shared identical VNTR band profiles and thus apomictic propagation was not detected; (2) the mean number of bands scored per individual was 24.3 (SD = 3.91) and the proportion of polymorphic loci within populations ranged from 0.69 to 1.00 (mean = 0.86 ± SD = 0.085); (3) the average proportion of bands shared between individuals within populations ranged from 0.39 to 0.67 (0.50 ± 0.067), while average interpopulation similarity ranged from 0.21 to 0.50 (0.32 ± 0.092); and (4) estimated heterozygosity within populations ranged from 0.42 to 0.79 (0.62 ± 0.083), while interpopulation heterozygosity ran from 0.62 to 0.81 (0.74 ± 0.062). Permutation tests were used to estimate the statistical significance of differences in similarity between populations. A Luzon population isolated by 1200 km was always significantly different in similarity tests when compared with each of the other three populations, all located on Mindanao (and separated by at least 100 km but less than 250 km). Of the latter three, only one population differed significantly from the other two in the degree of VNTR markers shared, possibly reflecting biogeographic partitioning suggested for the island. Across all populations, average estimated Fst was 0.154, although mean inter-island Fst (0.224) was significantly higher than mean intra-island Fst (0.085). These results suggest that, while intra-island gene flow is relatively high, significant differentiation of tropical species may occur even over short distances on individual islands. Preservation of only a limited number of populations may result in a significant loss of genetic diversity in such species.
Second-hand consumption as a way of life: public auctions in the surroundings of Alost in the late eighteenth century
Authors: DAMME ILJA VAN , VERMOESEN REINOUD
Published: July 2009

This article seeks to place second-hand consumption, or the reuse of older objects, into the expanding historical literature on early modern consumer practices. It claims that the study of second-hand consumption remains a much neglected topic of historical interest. Further empirical research of pre-industrial reuse habits is needed to examine essential problems and inconsistencies concerning consumers and their handling of older goods. On the basis of rarely used sources relating to public auctions in the countryside of the southern Netherlands, key questions regarding the current debate will be addressed. These questions concern the products that were handled, the actors involved, and how reuse was (or was not) affected by broader changes in society.
Changes in Old Bailey trials for the murder of newborn babies, 1674–1803
Authors: CLAYTON MARY
Published: July 2009

Although women accused of murdering their newborn infants were tried under the 1624 Act to Prevent the Destroying and Murdering of Bastard Children throughout the eighteenth century, their treatment changed significantly, at least in London, between the last quarter of the seventeenth century and 1803. This article charts these changes through an analysis of the accounts of trials held at the Old Bailey. These reflect three interwoven and interdependent strands of change: the development of a range of successful defence strategies, changes in courtroom procedures and the increased participation of lawyers, and a greater use of and reliance on medical witnesses and their evidence.
The devil's mark: a socio-cultural analysis of physical evidence
Authors: DARR ORNA ALYAGON
Published: July 2009

This article discusses the search for ‘the devil's mark’ as an example of the social embeddedness of evidentiary methods. The belief in early modern England was that the devil branded the bodies of witches with symbolic yet concrete corporeal malformations such as marks and growths. Thus a bodily search for the devil's mark became a common procedure in witch-trials. The analysis here of the fierce debate about the probative value of this allegedly direct physical evidence demonstrates an affinity between the evidential dispositions of the participants and their social position. The meaning of this method of proof emerged in the context of different, sometimes inconsistent or even competing, cultural concepts.
MANAGEMENT CONUNDRUMS IN MULTIPLE PREGNANCIES WITH SELECTIVE REDUCTION, INTRAUTERINE FETAL DEATH OR SPONTANEOUS ABORTION
Authors: MOGRA RITU , MOORE DAVID LH , HYETT JON A
Published: July 2009

There has been a marked increase in the prevalence of twins, triplets and higher-order multiple pregnancies over the last 20 years due, in part, to delayed childbearing, but more significantly associated with the widespread introduction of assisted reproductive techniques. Once viability is confirmed these pregnancies pose a series of unique challenges to the obstetrician as the dynamic of the maternal – fetal relationship changes when there are two, or more, fetuses to consider. With the exception of postmaturity, all obstetric complications are more common in multiple pregnancies. Australian data shows perinatal mortality rates of 7, 25 and 63 per 1,000 births for singleton, twin (RR 3.4) and triplet (RR 8.5) pregnancies respectively; with similar rates reported in the UK and USA. While multiple pregnancies account for only 2% of births, they account for 20% of neonatal admissions and 12% of perinatal deaths – with a 5-fold increase in deaths before 1 year of age.
Emotion Regulation Questionnaire – Eine deutschsprachige Fassung des ERQ von Gross und John
Authors: Abler Birgit , Kessler Henrik
Published: July 2009

Zusammenfassung. Eines der ersten validierten Instrumente zur wissenschaftlichen Untersuchung von Emotionsregulationsprozessen, stellt der englischsprachige Emotion Regulation Questionnaire (ERQ) von Gross und John (2003) dar. Dieser erlaubt es, Präferenzen für zwei häufig angewandte Strategien zur Emotionsregulation, nämlich Unterdrückung (suppression) und Neubewertung (reappraisal) zu erfassen. Die deutsche Version wurde in drei Übersetzungsschritten an jeweils einer Gruppe von Studenten (n = 113/167/174) erprobt. Dabei stand eine möglichst enge Orientierung am englischen Original sowie die Optimierung der Faktoren-Ladungen auf die zwei Komponenten im Vordergrund. Eine Faktorenanalyse mit iterativer Kommunalitätenschätzung und Varimax-Rotation wurde verwendet. Entsprechend unserem Ziel erreichten die Alpha-Werte (innere Konsistenz) als Reliabilitätsmaß für Unterdrückung und Neubewertung die Durchschnittswerte des amerikanischen Originalfragebogens. Wir entwickelten ein Instrument, das einfach und in kurzer Zeit (5–10 min) zu beantworten ist und differenziert die beiden Emotionsregulationsstile Neubewertung und Suppression erfasst. Mögliche Anwendungsbereiche sind die Untersuchung von Depressionen und Angsterkrankungen und die Bewertung psychotherapeutischer Verfahren.
Entwicklung eines Fragebogens zur Erfassung Adaptiver Strategien in der Vereinbarkeit von Familie und Beruf (FASIV)
Authors: Kupsch Melanie , Schneewind Klaus A. , Reeb Christian
Published: July 2009

Zusammenfassung. Mit dem FASIV (Fragebogen zur Erfassung Adaptiver Strategien In der Vereinbarkeit von Familie und Beruf) steht erstmalig ein mehrdimensionales Instrument für die Erfassung Adaptiver Strategien im Bereich der Work-Family Balance Forschung zur Verfügung. Im vorliegenden Beitrag werden die Entwicklung des FASIV und erste Erfahrungen im Einsatz an einer nicht-repräsentativen Stichprobe von berufstätigen Paaren mit Kindern (N = 389 Paare) beschrieben. Das Instrument wurde in einer Längsschnittstudie zur zweiten Datenwelle eines internationalen Projekts zur Vereinbarkeit von Familie und Beruf bei jungen Zweiverdiener-Familien eingesetzt. Es wurden Prüfungen der faktoriellen Validität, der internen Konsistenz und Retest-Reliabilität sowie der differenziellen Validität der Skalen vorgenommen, die zu durchwegs zufrieden stellenden Ergebnissen führten. Die viel versprechenden Hinweise auf den Nutzen des FASIV für den ressourcen-orientierten Zugang zum Forschungs- und Arbeitsbereich der Work-Family Balance legen die Durchführung einer Studie auf der Basis einer repräsentativen Stichprobe von Zweiverdiener-Familien nahe und lassen weitere Validierungsstudien als lohnend erscheinen.
Sportpsychologiein den Niederlanden
Authors: Bakker Frank C. , Philippen Philipp B.
Published: July 2009

Zusammenfassung. Die Sportpsychologie in den Niederlanden hat in den vergangenen 25 Jahren eine erfolgreiche Entwicklung erlebt. Bis circa 1985 war die Stellung der Sportpsychologie relativ marginal; seitdem kann jedoch die Rede von einer beachtlichen Verbesserung sein. Der Lehre und Forschung auf dem Gebiet der Sportpsychologie wird an verschiedenen Universitäten gegenwärtig vermehrt Aufmerksamkeit geschenkt. Die Einstellung innerhalb der Sportwelt gegenüber der Sportpsychologie, wie beispielsweise der Unterstützung der Sportler durch mentales Training, ist auf der ganzen Linie positiv. Das durch den Sport und die Medien geformte Bild der Sportpsychologie ist damit wohlwollender als einstmals. Vor grob drei Jahren wurde die Akkreditierungsregelung eingeführt, wodurch die Qualität der Sportpsychologie gewahrt wird. Als direkte Folge dieser Regelung startete in 2007 die Ausbildung zum Angewandten Sportpsychologen, was die weitere Professionalisierung der Sportpsychologie markiert.
Instrumente des Personalmarketings aus Sicht von Studierenden
Authors: Kanning Uwe Peter , Schmalbrock Jessica , Wild Sarah
Published: July 2009

Zusammenfassung. Mit Hilfe einer explorativen Befragung von 317 Studierenden werden deren Kenntnisse und individuelle Beschäftigungen sowie die Einstellung zu acht verschiedenen Maßnahmen des Personalmarketings untersucht. Dabei wird zwischen drei Fächergruppen (Wirtschaftswissenschaftler, Techniker und Sozialwissenschaftler) und zwei Hochschulgruppen (Universität vs. Fachhochschule) unterschieden. Im Ergebnis zeigen sich deutliche Unterschiede in der Bekanntheit sowie der individuellen Beschäftigung mit einzelnen Marketingmaßnahmen. Studierende der Wirtschaftswissenschaften erreichen hier meist die höchsten Werte. Gleiches gilt der Tendenz nach für Studierende an Fachhochschulen. Zudem bewerten angehende Wirtschaftswissenschaftler und Studierende von Fachhochschulen einige wenige Marketingmaßnahmen positiver als die übrigen Probandengruppen. Dies geht damit einher, dass sich der Bekanntheitsgrad sowie die individuelle Beschäftigung bei mehreren Maßnahmen positiv auf deren Bewertung auswirken. Mit zunehmender Dauer des Studiums bzw. sinkendem Abstand zum Examen steigen zudem bei fast allen Maßnahmen deren Bekanntheitsgrad sowie das Ausmaß der individuellen Beschäftigung mit einer Maßnahme an.
Biogenic silica at the Bermuda Atlantic Time‐series Study site in the Sargasso Sea: Temporal changes and their inferred controls based on a 15‐year record
Authors: Krause Jeffrey W. , Lomas Michael W. , Nelson David M.
Published: July 2009

Upper water column biogenic silica (bSiO2) at the Bermuda Atlantic Time‐series Study (BATS) site in the western Sargasso Sea was measured biweekly to monthly from 1989 through 2003, and changes on four distinct timescales were observed. Mesoscale physical features, such as eddies, occasionally increase vertically integrated bSiO2 in the upper 120 m (∫bSiO2) by an order of magnitude or more (this degree of enhancement was observed in only 5 of 217 total profiles). There is a strong seasonal cycle in ∫bSiO2, with a maximum in spring followed by a ∼50% decline to a fall minimum. The ∫bSiO2 also varies on timescales of 3–6 years, parallel with phase shifts in the North Atlantic Oscillation; those changes appear to reflect diatom responses to the combined effects of changes in 18°C subtropical mode water volume and in the meteorological forcing that entrains nutrients into the lower euphotic zone. Removal of the seasonal cycle reveals a secular, ∼40% decline in ∫bSiO2 over the 15 years of the BATS record, concurrent in time with increases in vertically integrated abundances of dinoflagellates and prasinophytes in the upper 120 m. At the same time there has been a linear increase in density stratification in the upper 200 m, a linear decline in winter silicic acid supply in the upper 120 m, and a linear decline in the Si:N ratio on the 26.4 kg m−3 potential density isopycnal. The apparent 15‐year shift in autotrophic community composition, with decreasing ∫bSiO2 and increasing flagellates, may have impacted future biogeochemical processes in the Sargasso Sea by reducing the role of diatoms in this system.
Landscape partitioning and environmental gradient analyses of soil organic carbon in a permafrost environment
Authors: Hugelius Gustaf , Kuhry Peter
Published: July 2009

This study investigates landscape allocation and environmental gradients in soil organic carbon (C) storage in northeastern European Russia. The lowlands of the investigated Usa River Basin range from taiga with isolated permafrost to tundra vegetation on continuous permafrost. We compile and analyze databases on soil properties, permafrost, vegetation, and modeled climate. Mean soil C storage is estimated at 38.3 kg C m−2, with similar amounts in taiga and tundra regions. Permafrost soils hold 42% of the total soil C in the area. Peatlands dominate soil C storage with 72% of the total pool and 98% of permafrost C. Multivariate gradient analyses show that local vegetation and permafrost are strong predictors of soil chemical properties, overshadowing the effect of climate variables. This study highlights the importance of peatlands, particularly bogs, in bulk soil C storage. Soil organic matter stored in permafrost has higher C:N ratios than unfrozen material. Permafrost bogs constitute the main vulnerable C pool in the region. Remobilization of this frozen C can occur through gradual but widespread deepening of the active layer with subsequent talik formation or through more rapid but localized thermokarst erosion.
Lateral spreading of a near‐field river plume: Observations and numerical simulations
Authors: Chen Fei , MacDonald Daniel G. , Hetland Robert D.
Published: July 2009

Data collected from the near‐field region of the Merrimack River (Massachusetts) plume were analyzed to examine plume spreading. Estimates of the plume spreading rate were derived from a direct assessment of the spreading of clustered surface drifters and from density and velocity data along a cross‐plume arc. Additionally, plume spreading rates were also derived from highly resolved numerical model output (ROMS). These three distinct observational and numerical approaches have reasonable agreement and are compared favorably with observations using a control volume approach in a previous study. It is demonstrated that these three methods are valid to estimate the plume spreading rate. The observations and numerical simulations also allowed estimation of terms in the lateral momentum balance along streamline normals, perpendicular to surface layer streamlines. One principal finding of this study is that the dominant terms in the lateral momentum balance are the centrifugal force term associated with streamline curvature, the buoyancy term, the Coriolis term, and the interfacial stress term. Furthermore, the lateral momentum balance shows that the lateral spreading process is significantly affected by interfacial stress within the first 1 to 2 km but, thereafter, is locally inviscid. However, turbulent mixing continues to play an important role in modifying the spreading rate by adjusting the internal wave speed.
Calculations of cross‐polar discrimination spread for 20 GHz fixed satellite systems using rain microstructure information
Authors: Thurai M. , Bringi V. N.
Published: July 2009

Individual drop images in natural rain from a two‐dimensional video disdrometer (2DVD) have been processed to obtain their shapes, sizes, and orientation angles, which, in turn, have been used to derive their complex forward scattering amplitudes at 19.701 GHz. Using these calculations, the specific attenuation for horizontal and vertical polarizations and the specific differential attenuation and the specific differential phase of all drops over 1 min are determined. A point‐to‐path scaling is used to derive the total rain attenuation for both polarizations as well as the total differential attenuation and the total differential phase. A 19.701 GHz experimental Earth‐space link is simulated to determine the variation of cross‐polar discrimination versus copolar attenuation (XPD‐CPA) and the calculations are compared with 2 years of joint probability XPD‐CPA beacon measurements. The comparisons indicate clearly that the variations in drop shape and drop orientation can give rise to significant spread in XPD.
SKS/SKKS splitting and Taiwan orogeny
Authors: Kuo‐Chen Hao , Wu Francis T. , Okaya David , Huang Bor‐Shouh , Liang Wen‐Tzong
Published: July 2009

We determine 58 sets of splitting parameters, fast direction (φ) and delay time (δt), from broadband SKS/SKKS waves recorded at temporary and permanent stations in Taiwan. These and earlier results, from S and ScS as well as SKS, show an island‐wide pattern of φ alignment with N–NNE structural trends in southern and central Taiwan and then turn smoothly to EW following the structural bight in northern Taiwan. Remarkable differences in δt for eastern and southwestern events are found, resulting probably from a more anisotropic upper mantle in the east, under the Central Range. With δt an average of 1.3 seconds our observations are consistent with the hypothesis that the orogeny involves shear or flow in the upper mantle in central and southern Taiwan. In northern Taiwan, near the ends of the collision and subduction zones, the extrusion and the hydration of olivine may contribute to the orientation of φ.
Emission of non‐thermal microwave radiation by a Martian dust storm
Authors: Ruf Christopher , Renno Nilton O. , Kok Jasper F. , Bandelier Etienne , Sander Michael J. , Gross Steven , Skjerve Lyle , Cantor Bruce
Published: July 2009

We report evidence for the emission of non‐thermal microwave radiation by a deep Martian dust storm. The observations were made using an innovative detector that can discriminate between radiation of thermal and non‐thermal origin by measuring the high order moments of its electric field strength. Measurements with this detector, installed in a 34 m radio telescope of the Deep Space Network (DSN), were made for about 5 hours a day over a dozen days between 22 May and 16 June 2006. Non‐thermal radiation was detected for a few hours only when a 35 km deep Martian dust storm was within the field of view of the radio telescope on 8 June 2006. The spectrum of the non‐thermal radiation has significant peaks around predicted values of the lowest three modes of the Martian Schumann Resonance (SR). The SR results from electromagnetic standing waves formed in the concentric spherical cavity between the Martian surface and its ionosphere and forced by large‐scale electric discharge. Thus, the non‐thermal radiation was probably caused by electric discharge in the Martian dust storm.
Overview of the Second Texas Air Quality Study (TexAQS II) and the Gulf of Mexico Atmospheric Composition and Climate Study (GoMACCS)
Authors: Parrish D. D. , Allen D. T. , Bates T. S. , Estes M. , Fehsenfeld F. C. , Feingold G. , Ferrare R. , Hardesty R. M. , Meagher J. F. , Nielsen‐Gammon J. W. , Pierce R. B. , Ryerson T. B. , Seinfeld J. H. , Williams E. J.
Published: July 2009

The Second Texas Air Quality Study (TexAQS II) was conducted in eastern Texas during 2005 and 2006. This 2‐year study included an intensive field campaign, TexAQS 2006/Gulf of Mexico Atmospheric Composition and Climate Study (GoMACCS), conducted in August–October 2006. The results reported in this special journal section are based on observations collected on four aircraft, one research vessel, networks of ground‐based air quality and meteorological (surface and radar wind profiler) sites in eastern Texas, a balloon‐borne ozonesonde‐radiosonde network (part of Intercontinental Transport Experiment Ozonesonde Network Study (IONS‐06)), and satellites. This overview paper provides operational and logistical information for those platforms and sites, summarizes the principal findings and conclusions that have thus far been drawn from the results, and directs readers to appropriate papers for the full analysis. Two of these findings deserve particular emphasis. First, despite decreases in actual emissions of highly reactive volatile organic compounds (HRVOC) and some improvements in inventory estimates since the TexAQS 2000 study, the current Houston area emission inventories still underestimate HRVOC emissions by approximately 1 order of magnitude. Second, the background ozone in eastern Texas, which represents the minimum ozone concentration that is likely achievable through only local controls, can approach or exceed the current National Ambient Air Quality Standard of 75 ppbv for an 8‐h average. These findings have broad implications for air quality control strategies in eastern Texas.
Unstable angina associated with coronary arterial calcification in a thalassemia intermedia patient with a pseudoxanthoma elasticum‐like syndrome
Authors: Farmakis Dimitrios , Moyssakis Ioannis , Perakis Alexandros , Rombos Yiannis , Deftereos Spyros , Giakoumis Anastasios , Polymeropoulos Evangelos , Aessopos Athanasios
Published: July 2009

Abstract: The coexistence of a pseudoxanthoma elasticum (PXE)‐like syndrome in β‐thalassemia and other hemoglobinopathies is a recently established clinical entity that has been observed with a significant frequency and related to some severe, even life‐threatening complications. We present here a thalassemia intermedia patient who developed unstable angina in a setting of severe anemia and PXE‐related coronary arterial calcification. Besides the clinical significance of this PXE‐like syndrome, its acquired nature may introduce some new thoughts regarding the pathogenesis of atherosclerosis.
Overgrowth of a mouse model of Simpson– Golabi–Behmel syndrome is partly mediated by Indian Hedgehog
Authors: Capurro Mariana I , Li Fuchuan , Filmus Jorge
Published: July 2009

Loss‐of‐function mutations of Glypican 3 (Gpc3) cause the Simpson–Golabi–Behmel overgrowth syndrome (SGBS), and developmental overgrowth is observed in Gpc3‐null mice, a mouse model for SGBS. We recently reported that GPC3 inhibits Hedgehog (Hh) signalling by inducing its endocytosis and degradation. Here, we show that the developmental overgrowth observed in Gpc3‐null mice is, at least in part, a consequence of the hyperactivation of the Hh pathway. We bred Gpc3‐null mice with mice that are Hh signalling‐deficient owing to the lack of Indian Hh (Ihh), one of the three mammalian Hhs. We found that the Gpc3‐null mice showed a 29.9% overgrowth in an Ihh wild‐type background, whereas an Ihh‐null background partly rescues the overgrowth caused by the lack of Gpc3 as the double mutants were 19.8% bigger than the Ihh‐null mice. Consistent with the role of GPC3 in Hh endocytosis and degradation, the Gpc3‐null mice show increased levels of Ihh protein and signalling, but similar levels of Ihh messenger RNA.