Population structure and decay pattern of Phellinus tremulae in Populus tremula as determined by somatic incompatibility

1994 ◽  
Vol 72 (10) ◽  
pp. 1391-1396 ◽  
Author(s):  
L. Holmer ◽  
L. Nitare ◽  
J. Stenlid
Keyword(s):  
Population Structure ◽  
Key Words ◽  
Populus Tremula ◽  
The South ◽  
Somatic Incompatibility ◽  
The Core ◽  
Core Sequence ◽  
Route Of Infection ◽  
Decay Pattern ◽  
Fungal Dna

Isolates of the wood-decaying basidiomycete Phellinus tremulae were obtained from four different stands of aspen Populus tremula in the south of Sweden. Studies were made of somatic incompatibility among all isolated within each site. No genet could be found in more than one tree. From one stand, two trees were felled and samples were taken from stem discs every half metre up to 13 m. Eight genets were isolated from the two trees, four in each tree. Fungal DNA was amplified from five isolates representing three different genets in one tree. The core sequence of M13 was used as primer. The results agreed with those of the somatic incompatibility test. Forty-five samples were taken from small twigs from healthy-looking branches and trees, and isolates of Phellinus tremulae were obtained from three of them. The likely route of infection of Phellinus tremulae in aspen is discussed. Key words: somatic incompatibility, Phellinus tremulae, Populus tremula.

scholarly journals Niche partitioning by photosynthetic plankton as a driver of CO2-fixation across the oligotrophic South Pacific Subtropical Ocean

2021 ◽  
Author(s):  
Julia Duerschlag ◽  
Wiebke Mohr ◽  
Timothy G. Ferdelman ◽  
Julie LaRoche ◽  
Dhwani Desai ◽  
...  
Keyword(s):  
Mixed Layer ◽  
Niche Partitioning ◽  
Euphotic Zone ◽  
South Pacific ◽  
Niche Differentiation ◽  
Surface Mixed Layer ◽  
The South ◽  
The Core ◽  
Photosynthetic Eukaryotes ◽  
Phytoplankton Communities

AbstractOligotrophic ocean gyre ecosystems may be expanding due to rising global temperatures [1–5]. Models predicting carbon flow through these changing ecosystems require accurate descriptions of phytoplankton communities and their metabolic activities [6]. We therefore measured distributions and activities of cyanobacteria and small photosynthetic eukaryotes throughout the euphotic zone on a zonal transect through the South Pacific Ocean, focusing on the ultraoligotrophic waters of the South Pacific Gyre (SPG). Bulk rates of CO2 fixation were low (0.1 µmol C l−1 d−1) but pervasive throughout both the surface mixed-layer (upper 150 m), as well as the deep chlorophyll a maximum of the core SPG. Chloroplast 16S rRNA metabarcoding, and single-cell 13CO2 uptake experiments demonstrated niche differentiation among the small eukaryotes and picocyanobacteria. Prochlorococcus abundances, activity, and growth were more closely associated with the rims of the gyre. Small, fast-growing, photosynthetic eukaryotes, likely related to the Pelagophyceae, characterized the deep chlorophyll a maximum. In contrast, a slower growing population of photosynthetic eukaryotes, likely comprised of Dictyochophyceae and Chrysophyceae, dominated the mixed layer that contributed 65–88% of the areal CO2 fixation within the core SPG. Small photosynthetic eukaryotes may thus play an underappreciated role in CO2 fixation in the surface mixed-layer waters of ultraoligotrophic ecosystems.

Reconstruction of the last three millennia South American Monsoon variability over the Amazon basin using speleothem isotope records 

2021 ◽  
Author(s):  
Marcela Eduarda Della Libera de Godoy ◽  
Valdir F. Novello ◽  
Francisco William Cruz
Keyword(s):  
High Resolution ◽  
Amazon Basin ◽  
Rainfall Variability ◽  
Isotope Analysis ◽  
Core Region ◽  
South American ◽  
The South ◽  
Continuous Increase ◽  
South American Monsoon ◽  
The Core

<p>South American Monsoon System (SAMS) and its main feature, the South American Convergence Zone (SACZ) are responsible for the major distribution of moisture in South America. The current work presents a novel high-resolution oxygen isotope record (δ<sup>18</sup>O) based on speleothems from southwest Amazon basin (Brazil), right at SAMS' core region and SACZ onset, where there is still a gap of high resolution paleoclimate records. The novel δ<sup>18</sup>O record presents an average of 3 year-resolution, composed by 1344 stable isotope analysis performed in two speleothems with a well-resolved chronology (37 U/Th ages) with average errors <1%. This work aims to describe the rainfall variability of the core region of the South American monsoon for the last 3k years and to take a broader look at precipitation patterns over Amazon basin. The Rondônia δ18O record shows three main stages throughout this time period. The first is from -1000 to ~400 CE, where it’s in accordance with most of other paleorecords from the Amazon basin. the second segment  is from ~400 to 1200 CE, when there is a continuous increase in the δ18O record until it reaches its highest values around 850 CE during the MCA (800-1200 CE), which is in accordance with western Amazon records, whilst the record in eastern Amazon presents an opposite trend. Thus, a precipitation dipole over Amazon emerges from ~400 CE onwards, majorly triggered by anomalous climate changes such as MCA, where western (eastern) Amazon is drier (wetter). During LIA (1450-1800 CE), on the other hand, Rondônia record presents its lowest values, also agreeing with western records and with records under the influence of SACZ whilst on eastern Amazon a drier period is established. Therefore, with this novel paleoclimate record located at the core region of SAMS, it's possible to evidence the dynamics of the precipitation dipole over the Amazon region, as well as understand the SACZ intensity variations.</p>

The grand platform of Huangchengtai at Shimao site in Shenmu, Shaanxi

2021 ◽  
Vol 21 (1) ◽  
pp. 32-46
Keyword(s):  
The Other ◽  
The South ◽  
The Core ◽  
South Eastern ◽  
Multiple Contexts ◽  
Relative Chronology ◽  
The Absolute ◽  
Stone Carvings ◽  
Longshan Period

Abstract Remains of the grand platform in the locus of Huangchengtai at Shimao site in Shenmu, Shaanxi was discovered and excavated during the 2018–2019 season. The south-eastern corner and southern buttress of the platform were revealed. The locations of the other three sides of the buttresses were also preliminarily confirmed. As many as 70 stone carvings were discovered from multiple contexts, including the surface of the southern buttress, the floor of the corridor, as well as the debris of the southern buttress inside the corridor. The relative chronology of this platform and stone carvings cannot be later than the late Longshan period. The absolute date ranges from 2000 BCE to 1800 BCE. Fieldwork performed at the grand platform encourages multiple archaeological discussions, including the settlement layout within the Huangchengtai area, the nature of the settlement, and its role as the core of the Shimao site.

scholarly journals POPULATION STRUCTURE AND PRODUCTION OF COPAIBA OLEORESIN BETWEEN VALLEYS AND HILLSIDES OF THE MINING AREA OFTROMBETAS RIVER - PARÁ1

2016 ◽  
Vol 40 (1) ◽  
pp. 51-60 ◽  
Author(s):  
Jonas Gebara ◽  
Antenor Pereira Barbosa ◽  
Isabel Maria Gonçalves Azevedo ◽  
Bruno Oliva Gimenez
Keyword(s):  
Population Structure ◽  
Forest Inventory ◽  
Sustainable Management ◽  
Natural Populations ◽  
Mining Area ◽  
National Forest ◽  
The South ◽  
Potential Production ◽  
Average Value ◽  
Bauxite Ore

ABSTRACT We aimed in this work to study natural populations of copaiba (Copaifera multijuga Hayne) on the Monte Branco mountain at Porto Trombetas-PA, in order to support sustainable management and the exploitation of oleoresin from copaiba. We studied the population structure of copaiba on hillsides and valleys of the south face of Monte Branco, within Saracá Taquera National Forest, where bauxite ore was extracted in the biennium 2013-2014 by Mineração Rio do Norte (MRN). We produced a 100% forest inventory of the specie and of oleoresin extraction in order to quantify the potential production of the remaining area. The density of copaiba individuals with DBH > 30 cm was 0.33 individuals per hectare in the hillside and 0.25 individuals per hectare in the valley. Both environments presented a density of 0.28 individuals per hectare. The average copaiba oleoresin yield was 0.661±0.334 liters in the hillside and 0.765±0.280 liters in the valley. The average value of both environments together (hillside and valley) was 0.714±0.218 liters. From all individuals with DBH over 30 cm, 38 (58%) produced some amount of oleoresin, averaging 1.113±0.562 liters in the hillside, 1.329±0.448 liters in the valley and 1.190±0.355 liters in both environments together. The results show the need for planning the use of the surroundings of the study area in order to reach the required volume of copaiba to make feasible the sustainable management of oleoresin extraction in the region.

Study of factors influencing the transformation of mountain geosystems on the southern slope of the Greater Caucasus

2021 ◽  
Vol 07 (02) ◽  
pp. 75-77
Author(s):  
Zeynəb Zəkəriyyə qızı Qurbanzadə ◽  
Keyword(s):  
Key Words ◽  
Ecological Study ◽  
Southern Slope ◽  
The South ◽  
Anthropogenic Changes ◽  
Greater Caucasus ◽  
Factors Influencing ◽  
South Slope

In the article touched such issues as anthropogenic changes in the landscapes of the south slope of the Greater Caucasus, ecological study of enviromental impact, landscape optimization. There are also suggestions for more efficient use of rapidly growing anthropogenically affected landscapes. Key words: anthropogenic changes, Greater Caucasus, south slope, optimization, landscape Azərbaycanın şimal-şərq hissələrini əhatə edən təbii iqlim şəraiti, heyvanat və bitki aləminə, turizm və istirahət üçün əvəzolunmaz məziyyətlərinə, həm də zəngin yeraltı sərvətlərinə görə respublikamızın nadir ərazilərindən biri olan Böyük Qafqazın cənub yamacı getdikcə daha da intensivləşən antropogen təsirlərə məruz qalan bir tədqiqat obyekti kimi nəzəri cəlb edir.

Introduction

2018 ◽  
pp. 1-16
Author(s):  
Devin Caughey
Keyword(s):  
Democratic Regime ◽  
The South ◽  
Southern Politics ◽  
The Core ◽  
Racial Issues ◽  
Congressional Representation ◽  
The One ◽  
Partisan Competition ◽  
The New Deal

This introductory chapter lays down the groundwork for the argument that the white polyarchy model provides the best account of congressional representation in the one-party South. This framework characterizes the South as an exclusionary one-party enclave, which departed from normal democratic politics in three major respects: its exclusion of many citizens from the franchise, its lack of partisan competition, and its embeddedness within a national democratic regime. Each of these features had important implications for Southern politics. The argument here is that white polyarchy provides the best description of congressional politics in the South, but this argument also rests on a number of empirical premises. To that end, the chapter outlines a focus on the issues of regulation, redistribution, and social welfare at the core of the New Deal agenda, largely bracketing explicitly racial issues except insofar as they intersected with economic policymaking. Finally, it outlines the major implications set out by this argument for our understanding of the character and persistence of the South's exclusionary one-party enclaves.

LEU3 of Saccharomyces cerevisiae activates multiple genes for branched-chain amino acid biosynthesis by binding to a common decanucleotide core sequence

1988 ◽  
Vol 8 (7) ◽  
pp. 2690-2697
Author(s):  
P Friden ◽  
P Schimmel
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acid ◽  
Upstream Region ◽  
Promoter Regions ◽  
Sequence Element ◽  
The Core ◽  
Core Sequence ◽  
Flanking Sequences ◽  
Branched Chain

LEU3 of Saccharomyces cerevisiae encodes an 886-amino-acid polypeptide that regulates transcription of a group of genes involved in leucine biosynthesis and has been shown to bind specifically to a 114-base-pair DNA fragment of the LEU2 upstream region (P. Friden and P. Schimmel, Mol. Cell. Biol. 7:2707-2717, 1987). We show here that, in addition to LEU2, LEU3 binds in vitro to sequences in the promoter regions of LEU1, LEU4, ILV2, and, by inference, ILV5. The largely conserved decanucleotide core sequence shared by the binding sites in these genes is CCGGNNCCGG. Methylation interference footprinting experiments show that LEU3 makes symmetrical contacts with the conserved bases that lie in the major groove. Synthetic oligonucleotides (19 to 29 base pairs) which contain the core decanucleotide and flanking sequences of LEU1, LEU2, LEU4, and ILV2 have individually been placed upstream of a LEU3-insensitive test promoter. The expression of each construction is activated by LEU3, although the degree of activation varies considerably according to the specific oligonucleotide which is introduced. A promoter construction with substitutions in the core sequence remains LEU3 insensitive, however. One of the oligonucleotides (based on a LEU2 sequence) was also tested and shown to confer leucine-sensitive expression on the test promoter. The results demonstrate that only a short sequence element is necessary for LEU3-dependent promoter binding and activation and provide direct evidence for an expanded repertoire of genes that are activated by LEU3.

Advancing the Global Perspective of Tourism by Examining Core and Peripheral Destinations

2015 ◽  
pp. 37-53
Author(s):  
Frances Cassidy ◽  
Margee Hume
Keyword(s):  
Statistical Data ◽  
South Pacific ◽  
Development Planning ◽  
Global Perspective ◽  
The South ◽  
The Core ◽  
Main Population

Core and peripheral destinations are very significant to island tourism because of core and peripheral islands. Peripheral locations may be disadvantaged as they are isolated from the core or economic centers and from the main population. This chapter reviews literature on the complexity of core and peripheral destinations, their development, planning, marketing and management together with local resident's perceptions of tourists and the tourist's expectations. The South Pacific is defined and it's Colonial past discussed together with tourist motivations. It is becoming increasingly difficult for all stakeholders to agree on programs and tourism practices and that various South Pacific countries have different ways of collecting statistical data resulting in few generic standards to adhere to.

Advancing the Global Perspective of Tourism by Examining Core and Peripheral Destinations

2019 ◽  
pp. 295-312
Author(s):  
Frances Cassidy ◽  
Margee Hume
Keyword(s):  
Statistical Data ◽  
South Pacific ◽  
Development Planning ◽  
Global Perspective ◽  
The South ◽  
The Core ◽  
Main Population

Core and peripheral destinations are very significant to island tourism because of core and peripheral islands. Peripheral locations may be disadvantaged as they are isolated from the core or economic centers and from the main population. This chapter reviews literature on the complexity of core and peripheral destinations, their development, planning, marketing and management together with local resident's perceptions of tourists and the tourist's expectations. The South Pacific is defined and it's Colonial past discussed together with tourist motivations. It is becoming increasingly difficult for all stakeholders to agree on programs and tourism practices and that various South Pacific countries have different ways of collecting statistical data resulting in few generic standards to adhere to.

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