Search results for "knot"
showing 10 items of 156 documents
Integrated management strategies of Meloidogyne incognita and Pseudopyrenochaeta lycopersici on tomato using a Bacillus firmus-based product and two …
2019
Abstract Because of the restrictions on chemical pesticide use and their negative effects on the environment, as well as on human and animal health, alternative strategies for plant pest and pathogen managements are highly desirable. The objective of this work was to evaluate the suitability of a commercial formulation of Bacillus firmus strain 1-1582, applied either alone or in combination with oxamyl or fosthiazate, to control the southern root-knot nematode Meloidogyne incognita and the fungal plant pathogen Pseudopyrenochaeta lycopersici under greenhouse conditions during two tomato crop cycles. Application of B. firmus suppressed nematode population levels during the second crop cycle …
Automatic measurement of wood fiber orientation and knot detection using an optical system based on heating conduction.
2015
In this paper, a new approach to computing the deviation of wood grain is proposed. To do this, the thermal conduction properties of timber are used (higher conduction in the fiber direction). Exciting the surface of the wood with a laser and capturing the thermal conduction using a thermal camera, an ellipse can be observed. Using a method similar to the tracheid effect, it is possible to extract information from this ellipse, such as the slope of grain and the presence of knots. With this method it is therefore possible to extend the mechanical model (assessing the mechanical properties of timber) to take certain singularities into account. Using this approach, the slope of grain can be e…
Robust link prediction in criminal networks: A case study of the Sicilian Mafia
2020
Abstract Link prediction exercises may prove particularly challenging with noisy and incomplete networks, such as criminal networks. Also, the link prediction effectiveness may vary across different relations within a social group. We address these issues by assessing the performance of different link prediction algorithms on a mafia organization. The analysis relies on an original dataset manually extracted from the judicial documents of operation “Montagna”, conducted by the Italian law enforcement agencies against individuals affiliated with the Sicilian Mafia. To run our analysis, we extracted two networks: one including meetings and one recording telephone calls among suspects, respect…
Periodontal Diseases in Diabetes Melitus - A Two Way Link? A Review of Literature
2020
Abstract Numerous studies in the last decades report a frequent association of marginal periodontal disease with some systemic metabolic disorders, such as diabetes or obesity. The prevalence of these diseases is growing alarmingly both globally and in our country. Recent data from the literature confirm that advanced forms of periodontal disease can influence the evolution of type 2 diabetes. This may provide a premise for better glycemic control.
Entropic Interactions between Two Knots on a Semiflexible Polymer.
2017
Two knots on a string can either be separated or intertwined, and may even pass through each other. At the microscopic scale, such transitions may occur spontaneously, driven by thermal fluctuations, and can be associated with a topological free energy barrier. In this manuscript, we study the respective location of a trefoil ( 3 1 ) and a figure-eight ( 4 1 ) knot on a semiflexible polymer, which is parameterized to model dsDNA in physiological conditions. Two cases are considered: first, end monomers are grafted to two confining walls of varying distance. Free energy profiles and transition barriers are then compared to a subset of free chains, which contain exactly one 3 1 and one 4 1 kn…
KnotGenome: a server to analyze entanglements of chromosomes.
2018
Abstract The KnotGenome server enables the topological analysis of chromosome model data using three-dimensional coordinate files of chromosomes as input. In particular, it detects prime and composite knots in single chromosomes, and links between chromosomes. The knotting complexity of the chromosome is presented in the form of a matrix diagram that reveals the knot type of the entire polynucleotide chain and of each of its subchains. Links are determined by means of the Gaussian linking integral and the HOMFLY-PT polynomial. Entangled chromosomes are presented graphically in an intuitive way. It is also possible to relax structure with short molecular dynamics runs before the analysis. Kn…
The Crystal Structure of Gurmarin, a Sweet Taste–Suppressing Protein: Identification of the Amino Acid Residues Essential for Inhibition
2018
International audience; Gurmarin is a highly specific sweet-taste suppressing protein in rodents that is isolated from the Indian plant Gymnemasylvestre. Gurmarin consists of 35 amino acid residues containing three intramolecular disulfide bridges that form a cystine knot. Here, we report the crystal structure of gurmarin at a 1.45 Å resolution and compare it with previously reported NMR solution structures. The atomic structure at this resolution allowed us to identify a very flexible region consisting of hydrophobic residues. Some of these amino acid residues had been identified as a putative binding site for the rat sweet taste receptor in a previous study. By combining alanine-scanning …
Are There Knots in Chromosomes?
2017
Recent developments have for the first time allowed the determination of three-dimensional structures of individual chromosomes and genomes in nuclei of single haploid mouse embryonic stem (ES) cells based on Hi⁻C chromosome conformation contact data. Although these first structures have a relatively low resolution, they provide the first experimental data that can be used to study chromosome and intact genome folding. Here we further analyze these structures and provide the first evidence that G1 phase chromosomes are knotted, consistent with the fact that plots of contact probability vs sequence separation show a power law dependence that is intermediate between that of a fractal globule …
Word derivational knowledge and writing proficiency: How do they link?
2016
Abstract Although word derivational (WD) knowledge, i.e., how new words are formed from existing words with help of derivational affixes, is considered important for learners of second or foreign languages (L2), there is still no clear answer as to what aspects comprise the construct of L2 English word derivational knowledge and how it develops. The present study adds to our knowledge on how the ability to derive English words develops among L2 English learners. More specifically, it sheds light on how word derivational knowledge relates to communicatively defined Common European Framework of Reference (CEFR) language proficiency levels regarding learners' writing skills. In the study, 117 …
A NEW SYMMETRIC AND POSITIVE DEFINITE BOUNDARY ELEMENT FORMULATION FOR LATERAL VIBRATIONS OF PLATES
1997
Abstract A new symmetric and positive definite boundary element method in the time domain is presented for the dynamic analysis of thin elastic plates. The governing equations of the problem are obtained from a variational principle in which a hybrid modified functional is employed. The functional is expressed in terms of the domain and boundary basic variables in plate bending, assumed to be independent of each other. In the discretized model the boundary variables are expressed by nodal values, whereas the internal displacement field is modelled by a superposition of static fundamental solutions. The equations of motion are deduced from the functional stationarity conditions and they cons…