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2021 ◽  
Vol 21 (23) ◽  
pp. 17855-17864
Author(s):  
András Hoffer ◽  
Ádám Tóth ◽  
Beatrix Jancsek-Turóczi ◽  
Attila Machon ◽  
Aida Meiramova ◽  
...  

Abstract. The production and use of plastics is increasing rapidly as they are widely used in packaging, construction materials, furniture, foils, etc. As a consequence of their widespread use and often disposable nature, vast streams of plastic waste are continuously generated, a considerable fraction of which are combusted in households worldwide. In this paper, various types of commonly used plastics (PE, PET, PP, PU, PVC, PS, ABS) as well as treated wood samples (LDF, low-density fibreboard) and firewood were combusted separately in a test stove under controlled conditions. The particulates emitted during the combustion test were collected on filters, potential tracers for each waste type were identified by GC-MS, and their relative abundances were determined. The emission factor of 1,3,5-triphenylbenzene was found to be higher for polymers containing aromatic rings in their structure. The application of terphenyls and quaterphenyls as tracer compounds has also been investigated. The trimer of styrene was found to be a potential tracer for the combustion of polystyrene and/or styrene-containing copolymers. Novel tracers were proposed for the burning of PET and furniture plates (LDF), which are among the most widely used waste types burned in households.


2021 ◽  
Vol 10 ◽  
pp. 130-150
Author(s):  
Jaideep Ghosh

This study focuses on investment structures and performances of family-controlled and non-affiliated publicly traded firms on the Indian market. While many influential, family-controlled firms dominate a large part of the Indian industry today, this study finds that a considerable fraction of the non-affiliated firms are able to maintain stable financial performance by forging strategic ties with other non-affiliated firms in transactional supply-chains modes. This study contributes to the understanding of the question concerning how investment structures of firms might be governed through interfirm ties of coordinated and cooperative investments. The results have important implications for the markets of emerging economies in the Asia-Pacific and the Southeast Asian regions.


Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3988
Author(s):  
Bartosz Ambroży Greń ◽  
Pawel Dabrowski-Tumanski ◽  
Wanda Niemyska ◽  
Joanna Ida Sulkowska

Complex lasso proteins are a recently identified class of biological compounds that are present in considerable fraction of proteins with disulfide bridges. In this work, we look at complex lasso proteins as a generalization of well-known cysteine knots and miniproteins (lasso peptides). In particular, we show that complex lasso proteins with the same crucial topological features—cysteine knots and lasso peptides—are antimicrobial proteins, which suggests that they act as a molecular plug. Based on an analysis of the stability of the lasso piercing residue, we also introduce a method to determine which lasso motif is potentially functional. Using this method, we show that the lasso motif in antimicrobial proteins, as well in that in cytokines, is functionally relevant. We also study the evolution of lasso motifs, their conservation, and the usefulness of the lasso fingerprint, which extracts all topologically non-triviality concerning covalent loops. The work is completed by the presentation of extensive statistics on complex lasso proteins to analyze, in particular, the strange propensity for “negative” piercings. We also identify 21 previously unknown complex lasso proteins with an ester and a thioester bridge.


2021 ◽  
Author(s):  
András Hoffer ◽  
Ádám Tóth ◽  
Beatrix Jancsek-Turóczi ◽  
Attila Machon ◽  
Aida Meiramova ◽  
...  

Abstract. The production and use of plastics increases rapidly as they are widely used in packaging, construction materials, furniture, foils, etc. As a consequence of their widespread use and often disposable character, vast streams of plastic wastes are continuously generated, a considerable fraction of which are combusted in households worldwide. In this paper, various types of commonly used plastics (PE, PET, PP, PU, PVC, PS, ABS), as well as treated wood samples (LDF) and firewood were combusted separately in a test stove under controlled conditions. The particulates emitted during the combustion test were collected on filters, and potential tracers for each waste type were identified by GC-MS, and their relative abundances were determined. The emission factor of 1,3,5-triphenylbenzene was found to be higher for polymers containing aromatic rings in their structure. The application of terphenyls and quarterphenyls as tracer compounds has also been investigated. The trimer of styrene was found to be a potential tracer for the combustion of polystyrene and/or styrene containing copolymers. Novel tracers were proposed for the burning of PET and furniture plates (LDF), which are among the most widely used waste types burned in households.


Author(s):  
Luis A. Balona

About 22,000 Kepler stars, 7,000 K2 stars, and nearly 60,000 TESS stars from sectors 1–24 have been classified according to variability type. A large proportion of stars of all spectral types appear to have periods in their light curves consistent with the expected rotation periods. A previous analysis of A- and late B-type stars suggests that these stars are indeed rotational variables. In this paper we have accumulated data to show that rotational modulation is present in about 30–40% of A- and B-type stars. A search for flares in TESS A- and B-type stars resulted in the detection of 102 flares in 57 stars. Analysis of flare energies show that the source of the flares cannot be a cool dwarf companion nor a F/G giant. The realization that a considerable fraction of A- and B-type stars are active indicates that a revision of current concepts regarding hot star envelopes is required.


Life ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 140
Author(s):  
Giuliana Fusco ◽  
Stefano Gianni

The discovery that a considerable fraction of the eukaryotic proteins lacks a well-defined three-dimensional structure in their native state has revolutionised our general understanding of proteins [...]


Zootaxa ◽  
2020 ◽  
Vol 4896 (2) ◽  
pp. 251-264
Author(s):  
BENJAMIN MICHAEL MARSHALL ◽  
PAUL FREED ◽  
LAURIE J. VITT ◽  
PEDRO BERNARDO ◽  
GERNOT VOGEL ◽  
...  

No central online repository exists for the collection of animal images; hence it remains unclear how extensively species have been illustrated in the published literature or online. Here we compiled a list of more than 8000 reptile species (out of 11,341) that have photos in one of six popular online repositories, namely iNaturalist (6,349 species), the Reptile Database (5,144), Flickr (4,386), CalPhotos (3,071), Wikimedia (2,952), and Herpmapper (2,571). These sites have compiled over one million reptile photos, with some species represented by tens of thousands of images. Despite the number of images, many species have only one or a few images. This suggests that a considerable fraction of morphological and geographic variation is under documented or difficult to access. We highlight prominent gaps in amphisbaenians, lizards, and snakes, with geographic hotspots for species without images in Central Africa, Pacific Islands, and the Andes Mountains. We present a list of ~3,000 species without photos in any of the six databases and ask the community to fill the gaps by depositing images on one of these sites (preferably with minimal copyright restrictions). 


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Xing-Xing Shen ◽  
Yuanning Li ◽  
Chris Todd Hittinger ◽  
Xue-xin Chen ◽  
Antonis Rokas

AbstractPhylogenetic trees are essential for studying biology, but their reproducibility under identical parameter settings remains unexplored. Here, we find that 3515 (18.11%) IQ-TREE-inferred and 1813 (9.34%) RAxML-NG-inferred maximum likelihood (ML) gene trees are topologically irreproducible when executing two replicates (Run1 and Run2) for each of 19,414 gene alignments in 15 animal, plant, and fungal phylogenomic datasets. Notably, coalescent-based ASTRAL species phylogenies inferred from Run1 and Run2 sets of individual gene trees are topologically irreproducible for 9/15 phylogenomic datasets, whereas concatenation-based phylogenies inferred twice from the same supermatrix are reproducible. Our simulations further show that irreproducible phylogenies are more likely to be incorrect than reproducible phylogenies. These results suggest that a considerable fraction of single-gene ML trees may be irreproducible. Increasing reproducibility in ML inference will benefit from providing analyses’ log files, which contain typically reported parameters (e.g., program, substitution model, number of tree searches) but also typically unreported ones (e.g., random starting seed number, number of threads, processor type).


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Brice Noël ◽  
C. L. Jakobs ◽  
W. J. J. van Pelt ◽  
S. Lhermitte ◽  
B. Wouters ◽  
...  

Abstract Compared to other Arctic ice masses, Svalbard glaciers are low-elevated with flat interior accumulation areas, resulting in a marked peak in their current hypsometry (area-elevation distribution) at  ~450 m above sea level. Since summer melt consistently exceeds winter snowfall, these low-lying glaciers can only survive by refreezing a considerable fraction of surface melt and rain in the porous firn layer covering their accumulation zones. We use a high-resolution climate model to show that modest atmospheric warming in the mid-1980s forced the firn zone to retreat upward by  ~100 m to coincide with the hypsometry peak. This led to a rapid areal reduction of firn cover available for refreezing, and strongly increased runoff from dark, bare ice areas, amplifying mass loss from all elevations. As the firn line fluctuates around the hypsometry peak in the current climate, Svalbard glaciers will continue to lose mass and show high sensitivity to temperature perturbations.


PhytoKeys ◽  
2020 ◽  
Vol 160 ◽  
pp. 7-43
Author(s):  
Jamilah Mohd Salim ◽  
Gaik Ee Lee ◽  
Muhamad Razali Salam ◽  
Salwa Shahimi ◽  
Elizabeth Pesiu ◽  
...  

The Setiu Wetlands, a unique area with nine interconnected habitats, comprises a considerable fraction of the total Peninsular Malaysia’s wetland flora. Although botanical collecting in the area has been active in the past 10 years, only a few studies dealing with the wetland flora have been published. Thus, a detailed checklist of this area is urgently needed to ensure the continuity of its inter-relating flora and fauna, as well as the livelihood of the local people. In this work we conducted a survey of the vascular plant flora of Setiu Wetlands and investigated the most important plants used by the local communities. Our checklist accounts for 406 taxa from 277 genera and 106 families, including 24 (6%) species of ferns and lycophytes, three gymnosperms, 257 (64%) dicotyledons and 122 (30%) monocotyledons. This comprehensive plant checklist will be a primary reference for the management of the newly gazetted Setiu Wetlands State Park covering more than 400 hectares of lands and water bodies.


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