scholarly journals Interspecific interactions through 2 million years: are competitive outcomes predictable?

2016 ◽  
Vol 283 (1837) ◽  
pp. 20160981 ◽  
Author(s):  
Lee Hsiang Liow ◽  
Emanuela Di Martino ◽  
Kjetil Lysne Voje ◽  
Seabourne Rust ◽  
Paul D. Taylor
Keyword(s):  
Null Hypothesis ◽  
Spatial Competition ◽  
Interspecific Interactions ◽  
Ecological Interactions ◽  
Time Period ◽  
Evolutionary Changes ◽  
Survival And Reproduction ◽  
Ecological Dominance ◽  
First Time

Ecological interactions affect the survival and reproduction of individuals. However, ecological interactions are notoriously difficult to measure in extinct populations, hindering our understanding of how the outcomes of interactions such as competition vary in time and influence long-term evolutionary changes. Here, the outcomes of spatial competition in a temporally continuous community over evolutionary timescales are presented for the first time. Our research domain is encrusting cheilostome bryozoans from the Wanganui Basin of New Zealand over a ca 2 Myr time period (Pleistocene to Recent). We find that a subset of species can be identified as consistent winners, and others as consistent losers, in the sense that they win or lose interspecific competitive encounters statistically more often than the null hypothesis of 50%. Most species do not improve or worsen in their competitive abilities through the 2 Myr period, but a minority of species are winners in some intervals and losers in others. We found that conspecifics tend to cluster spatially and interact more often than expected under a null hypothesis: most of these are stand-off interactions where the two colonies involved stopped growing at edges of encounter. Counterintuitively, competitive ability has no bearing on ecological dominance.

The sediment-landform assemblage in the forefield of the Gepatsch Glacier, Tirol, Austria and its preservation potential

2021 ◽  
Author(s):  
Daniel Le Heron ◽  
Bethan Davies ◽  
Lars Scharfenberg ◽  
Christoph Kettler ◽  
Michael Ketterman ◽  
...  
Keyword(s):  
Sedimentary Facies ◽  
Erosion And Deposition ◽  
Glacial Sediments ◽  
Time Period ◽  
Digital Elevation ◽  
Preservation Potential ◽  
Elevation Changes ◽  
Sand And Gravel ◽  
First Time

<p>Ongoing monitoring of the Gepatsch Glacier, Tirol (Austria) consists of a multifaceted, interdisciplinary project which aims to characterise short term (diurnal in the summer melt season) and longer term (annual to decadal) changes to the glacier snout and forefield in the context of a rapid retreating valley glacier. The glacial valley and forefield comprises amphibolites, para- and orthogneisses that have been smoothed and striated into whalebacks, compound bedrock-sediment bedforms (crag and tail structures), flutes, and annual moraines. The glacial sediments and landforms are undergoing incision and terrace development by meltwater streams. As part of a long term goal to characterise the rates of erosion, sedimentation, and re-deposition, we return to the same site each year in mid-July to collect airborne data with an UAV (Mavic Pro drone) that allows us to produce orthophotos and digital elevation models. We compute the daily and annual elevation changes, allowing us determine zones of erosion and deposition. Measureable evidence for erosion of flutes in the immediate glacial forefield has occurred over a 12-month time period. Till deposited within the last 20 years has undergone substantial mass wasting and re-deposition as subaerial mass flows, or reworked into stream deposits. The lee side of many whaleback structures completely lacks subglacial sediment, and contains instead a sand and gravel deposit interpreted to result from waterlain deposition. Thus, this case study area offers insight into the rates of erosion and deposition in a complex, proglacial setting, allowing some of these processes to be quantified for the first time. This approach is expected to yield a better understanding of the preservation potential of proglacial sedimentary facies, and hence their preservation potential in Earth’s sedimentary record.</p>

scholarly journals Temporal trends in respirable dust and respirable quartz concentrations within the European industrial minerals sector over a 15-year period (2002–2016)

2020 ◽  
Vol 77 (4) ◽  
pp. 268-275 ◽  
Author(s):  
Hicham Zilaout ◽  
Remko Houba ◽  
Hans Kromhout
Keyword(s):  
Economic Crisis ◽  
Temporal Trends ◽  
Personal Exposure ◽  
Respirable Dust ◽  
Industrial Minerals ◽  
Time Period ◽  
Global Economic Crisis ◽  
Exposure Levels ◽  
First Time

ObjectivesSince 2000 the European Industrial Minerals Association’s Dust Monitoring Programme (IMA-DMP) has systematically collected respirable dust and respirable quartz measurements from 35 companies producing industrial minerals. The IMA-DMP initiative allowed for estimating overall temporal trends in exposure concentrations for the years 2002–2016 and for presenting these trends by type of mineral produced, by jobs performed and by time of enrolment into the DMP.MethodsApproximately 32 000 personal exposure measurements were collected during 29 sampling campaigns during a 15-year period (2002–2016). Temporal trends in respirable dust and respirable quartz concentrations were studied by using linear mixed effects models.ResultsConcentrations varied widely (up to three to four orders of magnitude). However, overall decreases in exposure levels were shown for the European minerals industry over the 15-year period. Statistically significant overall downward temporal trends of −9.0% and −3.9% per year were observed for respirable dust and respirable quartz, respectively. When analyses were stratified by time period, no downward trends (and even slight increasing concentrations) were observed between 2008 and 2012, most likely attributable to the recent global economic crisis. After this time period, downward trends became visible again.ConclusionsConsistent and statistically significant downward trends were found for both exposure to respirable dust and respirable quartz. These downward trends became less or even reversed during the years of the global economic crisis. To our knowledge, this is the first time that analyses of long-term temporal trends point at an effect of a global economic crisis on personal exposure concentrations of workers from sites across Europe.

scholarly journals Long-term trends of <i>f</i>oE and geomagnetic activity variations

2003 ◽  
Vol 21 (3) ◽  
pp. 751-760 ◽  
Author(s):  
A. V. Mikhailov ◽  
B. A. de la Morena
Keyword(s):  
Geomagnetic Activity ◽  
Lower Thermosphere ◽  
Chemical Pollution ◽  
Anthropogenic Activity ◽  
Ionospheric Disturbances ◽  
Time Period ◽  
Long Term Trends ◽  
First Time ◽  
Long Term Variations

Abstract. A relationship between foE trends and geomagnetic activity long-term variations has been revealed for the first time. By analogy with earlier obtained results on the foF2 trends it is possible to speak about the geomagnetic control of the foE long-term trends as well. Periods of increasing geomagnetic activity correspond to negative foE trends, while these trends are positive for the decreasing phase of geomagnetic activity. This "natural" relationship breaks down around 1970 (on some stations later) when pronounced positive foE trends have appeared on most of the stations considered. The dependence of foE trends on geomagnetic activity can be related with nitric oxide variations at the E-layer heights. The positive foE trends that appeared after the "break down" effect may also be explained by the [NO] decrease which is not related to geomagnetic activity variations. But negative trends or irregular foE variations on some stations for the same time period require some different mechanism. Chemical pollution of the lower thermosphere due to the anthropogenic activity may be responsible for such abnormal foE behavior after the end of the 1960s.Key words. Ionosphere (ionosphere-atmosphere interactions; ionospheric disturbances)

Long term change observation of river terrain due to dam removal in Central Taiwan

2020 ◽  
Author(s):  
Tingray Liu ◽  
Chunhung Wu
Keyword(s):  
Cross Sections ◽  
Return Period ◽  
Dam Removal ◽  
The Third ◽  
Time Period ◽  
Accumulated Rainfall ◽  
Time Periods ◽  
Central Taiwan ◽  
First Time

&lt;p&gt;This research focuses on the long-term geomorphologic change in the upstream of the silt dams in the Lan-daw rivers watershed in central Taiwan, adopts the long-term rainfall records in the Lan-daw rivers watershed to calculate the 1-day, 2-days, 3-days accumulated rainfall with different return period, and analyzes the relationship between the geomorphologic change and the accumulated rainfall. This research builds the Digital Surface Models based on the photos shot by UAV at 9 different times. The river in upstream of the Lan-daw rivers watershed is sinuous. The research classifies 3 time periods from 2010 to August, 2019, including the first time period from 2010 to June, 2017, the second time period from June, 2017 to Nov. 2018, and the third time period from Nov. 2018 to Aug. 2019. The target in the first time period is to observe the geomorphologic change after the first dam removal, that in the second time period to observe the geomorphologic change in the 2 years after dam removal, and that in the third time period to observe the geomorphologic change after the second dam removal.&lt;/p&gt;&lt;p&gt;The longitudinal slopes in the first, second, and third time periods are -30.3%, 14.8%, and 5.98%, and the knickpoint in the longitudinal profile in the first and second time periods occur in the upstream 20 m of the silt dam and that in the third time periods occurs in the upstream 45 m of the silt dam. The research classifies the cross-sections profiles into 3 groups, including the first group from C1 to C7 cross sections, the second group from C8 to C14 cross sections, and the third group from C15 to C22 cross sections. The geomorphologic change in the first group near the silt dam is the most obvious in the three groups. The geomorphologic change in the three groups in the first time period are -6.43 m to -8.13 m (scouring), those in the second time period are 0.23 m to 0.34 m (deposition), and those in the third time period are 0.46 m (deposition) to -1.78 m (scouring). Based on the analysis of the long-term rainfall record in the Lan-daw river watershed, the return period of the heaviest rainfall from 2015 to Aug. 2019 is less than 20-year return period. This means that the geomorphologic change in upstream of silt dam in the Lan-Daw river watershed is easy induced in the short time after dam removal.&lt;/p&gt;

scholarly journals Evolution of organismal stoichiometry in a 50,000-generation experiment withEscherichia coli

2015 ◽  
Author(s):  
Caroline B. Turner ◽  
Brian D. Wade ◽  
Justin R. Meyer ◽  
Richard E. Lenski
Keyword(s):  
Phosphorus Content ◽  
Chemical Elements ◽  
Relative Proportion ◽  
Total Carbon ◽  
Ecological Interactions ◽  
Nitrogen And Phosphorus ◽  
Time Period ◽  
Evolutionary Changes ◽  
Selection For ◽  
Short Time

Organismal stoichiometry refers to the relative proportion of chemical elements in the biomass of organisms, and it can have important effects on ecological interactions from population to ecosystem scales. Although stoichiometry has been studied extensively from an ecological perspective, little is known about rates and directions of evolutionary changes in elemental composition in response to nutrient limitation. We measured carbon, nitrogen, and phosphorus content ofEscherichia colievolved under controlled carbon-limited conditions for 50,000 generations. The bacteria evolved higher relative nitrogen and phosphorus content, consistent with selection for increased use of the more abundant elements. Total carbon assimilated also increased, indicating more efficient use of the limiting element. Altogether, our study shows that stoichiometry evolved over a relatively short time-period, and that it did so in a predictable direction given the carbon-limiting environment.

Stability and Change in Emotional Intelligence: Exploring the Transition to Young Adulthood

2005 ◽  
Vol 26 (2) ◽  
pp. 100-106 ◽  
Author(s):  
James D.A. Parker ◽  
Donald H. Saklofske ◽  
Laura M. Wood ◽  
Jennifer M. Eastabrook ◽  
Robyn N. Taylor
Keyword(s):  
High School ◽  
Emotional Intelligence ◽  
Postsecondary Education ◽  
Life Transition ◽  
Full Time ◽  
Major Life ◽  
Long Term Stability ◽  
Time Period ◽  
Transition From High School

Abstract. The concept of emotional intelligence (EI) has attracted growing interest from researchers working in various fields. The present study examined the long-term stability (32 months) of EI-related abilities over the course of a major life transition (the transition from high school to university). During the first week of full-time study, a large group of undergraduates completed the EQ-i:Short; 32 months later a random subset of these students (N = 238), who had started their postsecondary education within 24 months of graduating from high school, completed the measures for a second time. The study found EI scores to be relatively stable over the 32-month time period. EI scores were also found to be significantly higher at Time 2; the overall pattern of change in EI-levels was more than can be attributed to the increased age of the participants.

Somatic Embryogenesis and In vitro Plant Regeneration in Vigna trilobata (L.) Verd. - A Potential Pasture Legume

1970 ◽  
Vol 19 (1) ◽  
pp. 89-99
Author(s):  
K. Choudhary ◽  
M. Singh ◽  
M. S. Rathore ◽  
N. S. Shekhawat
Keyword(s):  
Somatic Embryogenesis ◽  
Growth Regulators ◽  
Somatic Embryos ◽  
Basal Medium ◽  
Long Term Study ◽  
Continuous Application ◽  
First Time ◽  
Pasture Legume

This long term study demonstrates for the first time that it is possible to propagate embryogenic Vigna trilobata and to subsequently initiate the differentiation of embryos into complete plantlets. Initiation of callus was possible on 2,4-D. Somatic embryos differentiated on modified MS basal nutrient medium with 1.0 mg/l  of 2,4-D and 0.5 mg/l  of Kn. Sustained cell division resulted in globular and heart shape stages of somatic embryos. Transfer of embryos on to a fresh modified MS basal medium with 0.5 mg/l of Kn and 0.5 mg/l of GA3 helped them to attain maturation and germination. However, the propagation of cells, as well as the differentiation of embryos, were inhibited by a continuous application of these growth regulators. For this reason, a long period on medium lacking these growth regulators was necessary before the differentiation of embryos occurred again. The consequences for improving the propagation of embryogenic cultures in Vigna species are discussed. Key words: Pasture  legume, Vigna trilobata, Globular, Heart shape, somatic embryogenesis D.O.I. 10.3329/ptcb.v19i1.4990 Plant Tissue Cult. & Biotech. 19(1): 89-99, 2009 (June)

An Evaluation of Provincial Macroeconomic Performance in Vietnam

2017 ◽  
pp. 34-47
Author(s):  
Hoi Le Quoc ◽  
Nam Pham Xuan ◽  
Tuan Nguyen Anh
Keyword(s):  
Development Strategy ◽  
Institutional Transformation ◽  
Economic Indicators ◽  
Macroeconomic Performance ◽  
Economic Development Strategy ◽  
Socio Economic Development ◽  
The Cost ◽  
Development Objectives ◽  
First Time

The study was targeted at developing a methodology for constructing a macroeconomic performance index at a provincial level for the first time in Vietnam based on 4 groups of measurements: (i) Economic indicators; (ii) oriented economic indicators; (iii) socio-economic indicators; and (iv) economic - social – institutional indicators. Applying the methodology to the 2011 - 2015 empirical data of all provinces in Vietnam, the research shows that the socio-economic development strategy implemented by those provinces did not provide balanced outcomes between growth and social objectives, sustainability and inclusiveness. Many provinces focused on economic growth at the cost of structural change, equality and institutional transformation. In contrast, many provinces were successful in improving equality but not growth. Those facts threaten the long-term development objectives of the provinces.

Structure-Reactivity Relationships on Substrates and Inhibitors of the Lysine Deacylase Sirtuin 2 from Schistosoma Mansoni (SmSirt2)

2019 ◽  
Author(s):  
Daria Monaldi ◽  
Dante Rotili ◽  
Julien Lancelot ◽  
Martin Marek ◽  
Nathalie Wössner ◽  
...  
Keyword(s):  
Schistosoma Mansoni ◽  
Human Cancer ◽  
Egg Laying ◽  
Human Cancer Cells ◽  
Parasite Survival ◽  
Survival And Reproduction ◽  
Emergence Of Resistance ◽  
First Time ◽  
Parasitic Life Cycle

The only drug for treatment of Schistosomiasis is Praziquantel, and the possible emergence of resistance makes research on novel therapeutic agents necessary. Targeting of Schistosoma mansoni epigenetic enzymes, which regulate the parasitic life cycle, emerged as promising approach. Due to the strong effects of human Sirtuin inhibitors on parasite survival and reproduction, Schistosoma sirtuins were postulated as therapeutic targets. In vitro testing of synthetic substrates of S. mansoni Sirtuin 2 (SmSirt2) and kinetic experiments on a myristoylated peptide demonstrated lysine long chain deacylation as an intrinsic SmSirt2 activity for the first time. Focused in vitro screening of the GSK Kinetobox library and structure-activity relationships (SAR) of identified hits, led to the first SmSirt2 inhibitors with activity in the low micromolar range. Several SmSirt2 inhibitors showed potency against both larval schistosomes (viability) and adult worms (pairing, egg laying) in culture without general toxicity to human cancer cells.<br>

NEW VARIETIES OF CURRANTS AND GOOSEBERRY BREEDING PLANTS

1970 ◽  
pp. 41-46
Author(s):  
O. D. Golyaeva ◽  
O. V. Kurashev ◽  
S. D. Knyazev ◽  
А. Yu. Bakhotskaya
Keyword(s):  
Powdery Mildew ◽  
Genetic Basis ◽  
Black Currant ◽  
Leaf Spots ◽  
Agricultural Sciences ◽  
Berry Crops ◽  
New Varieties ◽  
First Time ◽  
Red Currant

The main goal of the scientific institution was and remains to improve the assortment of fruit and berry crops for the development of domestic horticulture. Black currant breeding at VNIISPK was started by A.F Tamarova and continued by the doctor of agricultural Sciences T.P.Ogoltsova and doctor of agricultural Sciences S.D. Knyazev. A long-term breeding program has been developed. The main goals of the program are to create black currant cultivars with continuous resistance to diseases, first of all powdery mildew, as wells resistance to pests, i.e. bud mite. As a result of the long-term work, over 40 black currant cultivars have been developed, 14 of them are zoned. Red currant breeding was led by the candidate of agricultural Sciences L.V. Bayanova; since 2001 the work has been continued by the candidate of agricultural Sciences O.D. Golyaeva. ‘Heinemanns Rote Spӓtlese’, the descendant of R. multiflorum Kit., was involved in the red currant breeding for the first time in Russia. On its genetic basis, a series of late maturing cultivars with long and dense racemes was created. At the Institute, in total 21cultivars of red currants have been developed, 13 of them are zoned. At present, red currant cultivars make up 25.5% of the zoned assortment in Russia. The first research on gooseberries was stated by V.P. Semakin and A.F Tamarova; since 1992 the systematic gooseberry breeding has been carried out by the candidate of agricultural Sciences O.V. Kurashev. On the basis of Grossularia robusta, we have created gooseberry forms that are resistant to powdery mildew and leaf spots. These forms are highly productive, weakly thorned, having bush habit suitable for mechanized harvest. The result of breeding activities was the transfer of 6 gooseberry cultivars to State agricultural testing: ‘Solnechny Zaychik’, ‘Nekrasovsky’, ‘Yupiter’, ‘Zemlianichny’, ‘Moryachok’ and ‘Discovery’.

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