Floristic and structural characteristics of a coastal heathland exhibiting symptoms of Phytophthora cinnamomi infestation in the eastern Otway Ranges, Victoria

2003 ◽  
Vol 51 (3) ◽  
pp. 283 ◽  
Author(s):  
W. Scott Laidlaw ◽  
Barbara A. Wilson

The floristics and structure of heathland vegetation exhibiting symptoms of Phytophthora cinnamomi Rands infestation was assessed at two sites in heathlands at Anglesea, Victoria. There were significant effects in both floristics and structure. Thirteen heathland species were significantly less abundant in diseased areas and 23 species were more abundant. Diseased (infested) vegetation, when compared with non-diseased areas, had less cover of Xanthorrhoea australis and shrub species and a greater cover of sedges, grasses and open ground. Structural differences were observed between heights 0 and 0.6 m, with a decline in cover recorded in diseased vegetation. Non-metric multidimensional scaling ordination of the floristic data showed a clear separation of diseased and non-diseased vegetation and that changes in floristic composition post-infestation were similar at both sites. Although there was some evidence of regeneration of X. australis, the recovery capacity of other susceptible species at Anglesea is unknown. The long-term consequences of loss of species and structure in the eastern Otways mean that the vegetation is unlikely to return to former status, especially if the pathogen continues to reinfect.

Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 451
Author(s):  
Marta Kubiak ◽  
Janine Mayer ◽  
Ingo Kampen ◽  
Carsten Schilde ◽  
Rebekka Biedendieck

In biocatalytic processes, the use of free enzymes is often limited due to the lack of long-term stability and reusability. To counteract this, enzymes can be crystallized and then immobilized, generating cross-linked enzyme crystals (CLECs). As mechanical stability and activity of CLECs are crucial, different penicillin G acylases (PGAs) from Gram-positive organisms have proven to be promising candidates for industrial production of new semisynthetic antibiotics, which can be crystallized and cross-linked to characterize the resulting CLECs regarding their mechanical and catalytic properties. The greatest hardness and Young’s modulus determined by indentation with an atomic force microscope were observed for CLECs of Bacillus species FJAT-PGA CLECs (26 MPa/1450 MPa), followed by BmPGA (Priestia megaterium PGA, 23 MPa/1170 MPa) and BtPGA CLECs (Bacillus thermotolerans PGA, 11 MPa/614 MPa). In addition, FJAT- and BtPGA CLECs showed up to 20-fold higher volumetric activities compared to BmPGA CLECs. Correlation to structural characteristics indicated that a high solvent content and low number of cross-linking residues might lead to reduced stability. Furthermore, activity seems to be restricted by small water channels due to severe diffusion limitations. To the best of our knowledge, we show for the first time in this study that the entire process chain for the characterization of diverse industrially relevant enzymes can be performed at the microliter scale to discover the most important relationships and limitations.


Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 903 ◽  
Author(s):  
Ivan Trifonov ◽  
Dmitry Trukhan ◽  
Yury Koshlich ◽  
Valeriy Prasolov ◽  
Beata Ślusarczyk

In this study we aimed to determine the extent to which changes in the share of renewable energy sources, their structural complex, and the level of energy security in Eastern Europe, Caucasus and Central Asia (EECCA) countries in the medium- and long-term are interconnected. The study was performed through modeling and determination of the structural characteristics of energy security in the countries. The methodology of the approach to modeling was based on solving the problem of nonlinear optimization by selecting a certain scenario. For the study, the data of EECCA countries were used. The ability of EECCA countries to benefit from long-term indirect and induced advantages of the transformation period depends on the extent to which their domestic supply chains facilitate the deployment of energy transformation and induced economic activity. This study provides an opportunity to assess the degree of influence of renewable energy sources on the level of energy security of countries in the context of energy resource diversification. The high degree of influence of renewable energy sources on energy security in the EECCA countries has been proven in the implementation of the developed scenarios for its increase. Energy security is growing. At the same time, its level depends not only on an increase in the share of renewable sources but also on the structure of energy resources complex of countries, and the development of various renewable energy sources. Therefore, today the EECCA countries are forced not only to increase the share of renewable energy sources but also to attach strategic importance to the structural content of their energy complex.


Author(s):  
K. Kalotay ◽  
A. Sulstarova

The former Soviet Union disintegrated three decades ago. That momentous 1991 was not only the starting point for independence of the countries of the post-Soviet space but also the starting point for their transformation from centrally planned economy to capitalism, often with local specificities. At the moment of writing this article aiming at analysing the long-term, structural characteristics of inward and outward foreign direct investment (FDI), these 12 economies are facing new COVID-19-related challenges, different from the problems of transformation undertaken in the past decades. After a brief literature survey, in which the main issues raised by academic research are highlighted, the article analyses the long-term trends and the main characteristics (geographical and sectoral) of FDI, with special reference to greenfield project announcements from 2003 on (the starting year of data availability). It also explores how much economic development was based on either attracting inward or promoting outward FDI or both. The performance of the 12 post-Soviet economies is controlled against the performance of other transition economies such as the Baltic States, South-East Europe and/or the Visegrad Group. The article concludes that indeed efforts towards using inward or outward FDI for development has been modest, even if in inflows one can observe some convergence with the other transition economies, which have been relying more wittingly using FDI for their development.


Algologia ◽  
2020 ◽  
Vol 30 (4) ◽  
pp. 393-405
Author(s):  
A.M. Solonenko ◽  
◽  
O.G. Bren ◽  

The article represents the results of long-term algological studies of hyperhaline reservoirs of the northwestern coast of the Azov Sea. The features of the floristic composition and taxonomic structure of algae in aquatic (water column and bottom), aquatic-terrestrial (water’s edge, dried up water bodies, drying area) and terrestrial (elevated non-flooding areas) habitats of these objects are displayed. A specificity of the studied algoflora lies in the absence of representatives of certain characteristic phyla for the salt-water and non-saline land and water habitats of the territory of Ukraine. It was established that species composition of the studied reservoirs is depleted in comparison with other non-saline and marine ecosystems. Totally, 123 algae species were identified. They represente 7 phyla, 10 classes, 27 orders, 47 families, 68 genera. The largest number of species included three phyla: Cyanoprocaryota – 65 species (52.9% of the total number of identified species), Bacillariophyta – 26 (21.1%), Chlorophyta – 22 (17.9%). The first places among the six leading orders were taken by cyanoprocaryotes from Oscillatoriales, Nostocales, Chroococcales and diatoms from Naviculales. The most numerous species at the family level are trichomous cyanoprocaryotes from Nostocaceae, Pseudanabaenaceae, and Phormidiaceae. There were found 23 leading genera – their species richness exceeds the average indicator (1.81 species). According to the results of original studies, it was noted that all taxonomic levels of algoflora of the hyperhaline reservoirs shows features of not only saline habitats, but also of the freshwater, marine and terrestrial extreme ecosystems. Such diversity of the algal population indicates an unstable hydrological regime and complex relations of water exchange between the hyperhaline reservoirs and nearby terrestrial and aquatic habitats.


Author(s):  
Z. K. Klimenko ◽  
S. A. Plugatar ◽  
V. K. Zykova ◽  
I. N. Kravchenko

The article presents the results of a long-term research on the introduction study and evaluation of cultivars of tea-hybrid roses introduced and selected by the Nikitsky Botanical Gardens to determine the possibilities of their use in floriculture of the Southern Coast of the Crimea. The research was conducted in the period from 1955 to 2014. The material for the study was 679 cultivars of garden roses from the tea-hybrid garden group of the collection of the Nikitsky Botanical Gardens. As a result of a comprehensive study, 400 cultivars are recommended for use in the floriculture of the Crimea. The main options for this use becomes the growing of tea-hybrid roses in the open ground for gardening purposes in bush and tree-shaped forms, as well as the growing cultivars for cutting in both open and protected ground. The biological features of the cultivars, which determine the possibility of different types of the use and the cultivars, that have these features were identified: 400 cultivars were recommended for use in landscaping in bush form, 45 cultivars - also in tree-shaped form, 226 cultivars are promising for cutting in the open ground and 107 cultivars - for forcing and cutting in greenhouses. The main methods of propagation of cultivars of tea-hybrid roses under the conditions of the Southern Coast of the Crimea are budding and rooting of green and hardwood cuttings. The optimal timing for propagation by each of these methods is indicated. The best rootstocks for budding were identified, depending on the type of their use in floriculture. 


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Bo Tao ◽  
Yuan Xiao ◽  
Hengyi Cao ◽  
Wenjing Zhang ◽  
Chengmin Yang ◽  
...  

Abstract Background The corpus callosum (CC) deficits have been well documented in chronic schizophrenia. However, the long-term impacts of antipsychotic monotherapies on callosal anatomy remain unclear. This cross-sectional study sought to explore micro- and macro-structural characteristics of the CC in never-treated patients and those with long-term mono-antipsychotic treatment. Methods The study included 23 clozapine-treated schizophrenia patients (CT-SCZ), 19 risperidone-treated schizophrenia patients (RT-SCZ), 23 never-treated schizophrenia patients (NT-SCZ), and 35 healthy controls (HCs). High resolution structural images and diffusion tensor imaging (DTI) data for each participant were obtained via a 3.0 T MR scanner. FreeSurfer was used to examine the volumes and fractional anisotropy (FA) values of the CC for each participant. Results There were significant deficits in the total and sub-regional CC volume and white matter integrity in NT-SCZ in comparison with healthy subjects. Compared with NT-SCZ, both CT-SCZ and RT-SCZ showed significantly increased FA values in the anterior CC region, while only RT-SCZ showed significantly increased volume in the mid-anterior CC region. Moreover, the volume of the mid-anterior CC region was significantly smaller in CT-SCZ compared to HCs. No correlations of clinical symptoms with callosal metrics were observed in schizophrenia patients. Conclusions Our findings provide insight into micro- and macro-structural characteristics of the CC in chronic schizophrenia patients with or without antipsychotics. These results suggest that the pathology itself is responsible for cerebral abnormalities in schizophrenia and that chronic exposure to antipsychotics may have an impact on white matter structure of schizophrenia patients, especially in those with risperidone treatment.


Author(s):  
Hyon Wook Ji ◽  
Dan Daehyun Koo ◽  
Jeong-Hee Kang

Cured-in-place pipe (CIPP), as a kind of trenchless sewer rehabilitation technology, is a method to repair sewer pipe using unsaturated polyester resin. This study develops a CIPP liner using hot water or steam curing as well as glass fiber, in contrast to traditional methods, which use nonwoven fabric. Composite material samples were fabricated by combining liner materials using various methods, and the structural characteristics of the liners were compared and analyzed through short- and long-term flexural strength tests. A long-term test was conducted for 10,000 h, and the results revealed 13.3 times higher flexural strength and 8 times higher flexural modulus than the American Society for Testing Materials minimum criteria for CIPP short-term properties. The maximum creep retention factor was 0.64, thereby reducing the design thickness of the CIPP by up to 54%. The structural characteristics also improved when glass fibers were mixed with traditional CIPP liner, making it possible to reduce the thickness by 30%. Glass fibers result in high structural strength when combined with unsaturated polyester resin. Structural strength increased, even when glass fibers were mixed with traditional CIPP liner. The main contribution of this research is the development of a high strength CIPP liner and improvement of the structural properties of CIPP lining without using the specially formulated resin or lining materials.


2013 ◽  
Vol 864-867 ◽  
pp. 2569-2576
Author(s):  
Wen Li Liu ◽  
Jing Gui Wu ◽  
Xin Yu Zhao

With dry sieving and wet sieving methods, we studied the distribution characteristics and stability of the aggregates in the typical orchard soils with different cultivation years in northern China under long-term freezing-thawing conditions. The results show that: the contents of the aggregates with particle size above 10 mm or between 0.25 and 10 mm are significantly increased with cultivation years and annual growth rates were respectively 1.28% and 0.078%. Fractal dimension in the orchard soils was gradually decreased and lower than that in uncultivated area near the orchard in corresponding cultivation year. MWD of orchard soils shows annual increasing trend of 0.76%. The content of the water stable macro aggregates in orchard soils was increased with the cultivation years and was about 11.65%-20.18% higher than that of uncultivated soils near the orchard. Average annual growth of orchard soils was 0.37%. Fractal dimension was decreased year by year on the water stable macro aggregates. MWD of the water stable macro aggregates was significantly greater than that of uncultivated soils near the orchard and increased with cultivation years. Aggregate destruction rate was gradually decreased to 31.61% of that in the 60th year and annual average decrease rate was 0.91%. Soil bulk density was gradually decreased.


1997 ◽  
Vol 45 (6) ◽  
pp. 1033 ◽  
Author(s):  
Andrew F. Le Brocque ◽  
Rod T. Buckney

The relationships between stand structure and floristic composition were examined from data collected from 100 quadrats on two soil types: Hawkesbury sandstone and Narrabeen group soils, occurring within Ku-ring-gai Chase National Park, New South Wales. Floristic composition was determined using the frequency of species occurring within nine concentric sub-quadrats of total area 500 m2. Stand structure was determined by a multivariate classification scheme utilising the foliage projective cover of eight strata within each quadrat. The patterns in floristic composition and stand structure were examined through multivariate analyses. Procrustes analysis of non-metric multidimensional scaling ordinations of both the stand structure and composition data showed floristic composition gradients to be well recovered by the structure data. Similar gradients were evident in both vegetation attributes, between and within the two soil types, with the rank order of community types across the ordinations being the same. However, some important differences were evident between the ordinations of floristic composition and stand structure between and within soil types. A number of floristically dissimilar communities exhibited very similar multivariate structural characteristics. In particular, two floristically distinct communities on different soil types were indistinguishable in terms of their structural characteristics. The multivariate analyses suggest a possible convergence of some compositionally distinct communities towards a common structural formation.


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