159 research outputs found
Substitution of sulfur by selenium; The supramolecular insight
The supramolecular approach is based on statistical analysis of data from crystal structures extracted
from the Cambridge Structural Database (CSD), quantum-chemical calculations for assess the
strength of typical interactions, and docking study for determination of the binding of S/Se
compounds to selected biomolecules. The statistical analysis has shown that S and Se atoms, in
fragments that corresponds to the side chains of cysteine (Cys), methionine (Met) selenocysteine
(Sec) and selenomethionine (Mse), display a similar tendency towards specific types of interaction.
The most numerous are structures with C-H/Se and C-H/S interactions (ā¼80%). The structures with
Se/Se and S/S interactions are notably less numerous (ā¼5%), although the C-H/Se and C-H/S
interactions (ā¼ā0.8 kcal/mol) are weaker than the most stable parallel Se/Se and S/S interactions
(ā¼ā3.3 kcal/mol) and electrostatic interactions of Ļ/Ļ type (ā¼ā2.6 kcal/mol). The significant
difference in numerosity can be explained by the abundance of C-H groups in analyzed crystal
structures. Docking studies revealed that S and Se rarely participate in interactions with the amino
acid residues of target enzymes, but the differences in the number and positions of their binding
sites between Se and S compounds are more pronounced if the substituents of S/Se atom are polar
and if there are more Se/S atoms in the ligand.Supramolekulski pristup zasnovan je na statistiÄkoj analizi podataka dobijenih iz kristalnih struktura, ekstrahovanih iz CSD-a (od eng. Cambridge Structural Database), kvantno-hemijskim proraÄunima za procenu jaÄine tipiÄnih interakcija, i na doking studiji za odreÄivanje vezivanja S/Se jedinjenja za odabrane biomolekule. StatistiÄka analiza je pokazala da atomi S i Se, u fragmentima koji odgovaraju boÄnim lancima cisteina (Cis), metionina (Met), selenocisteina (Sec) i
selenometionina (Mse), pokazuju sliÄnu tendenciju ka odreÄenim vrstama interakcija. Najbrojnije su
strukture sa C-H/Se i C-H/S interakcijama (~ 80%). Strukture sa Se/Se i S/S interakcijama su znatno
manje zastupljene u kristalnim strukturama (ā¼5%), iako su C-H/Se i C-H/S interakcije (ā¼ -0,8 kcal/mol) slabije od najstabilnijih Se/Se i S/S interakcija sa paralelnih orientacijom (ā¼ -3,3 kcal/mol) i njihovih elektrostatiÄkih interakcija Ļ/Ļ tipa (ā¼ -2,6 kcal/mol). ZnaÄajna razlika u brojnosti može se objasniti obiljem C-H grupa u analiziranim kristalnim strukturama. Doking studija je pokazala da S i Se atomi retko ukljuÄeni u interakcijama sa amino-kiselinskim ostacima ciljanih enzima, ali su razlike u broju i položajima vezivnih mesta izraženije ako su supstituenti vezani za S/Se polarni, ali i ako ligand poseduje viÅ”e od jednog Se ili S atoma
Influence of supramolecular structure in the crystals on water/aromatic parallel alignment interactions
The parallel alignment interactions between water molecules and C-6-aryl groups in crystal structures and influence of supramolecular structures in crystals were studied by analyzing data in the Cambridge Structural Database (CSD). Analyses of crystal structures from the CSD reveal that the water/aromatic parallel alignment interactions, where the water molecule or one of its O-H bonds is parallel to the aromatic ring plane, are very frequent at large horizontal displacements. These orientations, observed in crystal structures, were compared with the results of ab initio calculations and explained by influence of supramolecular structures in crystals
The Methodology of Monitoring the Implementation of a Strategy in an Electricity Distribution Enterprise
Lately, a greater emphasis has been placed on the quality of environment and sound management of resources, and above all on energy sources as the basis of the human life quality and of sustainable development. The sustainable development of an organization is monitored through the organizationās performance, which is the result of its strategy that has incorporated all stakeholdersā requirements beforehand. Although a great number of companies apply a strategic management concept and business success measurement methods, researches show that only every tenth company manages to implement the defined strategy. The main causes of unsuccessful strategy implementation can be found in the lack of adequate strategic control mechanisms. The paper presents the methodology developed with an aim to remove the main obstacles to successful implementation of the defined strategy and to the monitoring of an enterprise\u27s effectiveness
Development of a Quality Management Model in the Automotive Industry with a Focus on the Quality of Incoming Products (Part I)
The automotive industry is one of the main drivers of industrial production and is well known for high-quality criteria. In the past, original equipment manufacturers (OEMs) pushed forward the main processes of new vehicle production. Today, OEM transfers a great deal of high-level engineering tasks to suppliers. As automotive industries are highly automated robot lines, constituting serial production in millions, the smallest error in a delivered product/component causes the downtime for the whole line. In these situations, it is necessary to validate another supplier of the same component, which can last a very long time. This paper presents a quality management model for incoming components in the automotive industry which can recognize possible risks in the early phase of the component prototype development. The model is successfully applied in a company that produces components for OEM, which will be presented in the second part of the paper
Supplementary data for the article: BlagojeviÄ, J. P.; JanjiÄ, G. V.; ZariÄ, S. D. Very Strong Parallel Interactions between Two Saturated Acyclic Groups Closed with Intramolecular Hydrogen Bonds Forming Hydrogen-Bridged Rings. Crystals 2016, 6 (4). https://doi.org/10.3390/cryst6040034
Supplementary material for: [https://doi.org/10.3390/cryst6040034]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1928
RazliÄiti aspekti inhibicije rastenja i fotosinteze kukuruza (Zea mays L.) uzrokovanog herbicidom sulfosatom, 1 - manipulacija statusom korena
Effects of the herbicide sulphosate on growth, accumulation and partitioning of dry weight and photosynthesis in maize plants subjected to source-sink manipulation at the root were studied. The findings indicate that growth and dry weight accumulation correlate significantly only with the dry mass ratio and/or volume of the root (RMR, Vr, respectively), while a significant negative correlation was found with stem mass ratio (SMR) and generally with leaf mass ratio (LMR), which reflects an irregular distribution of carbohydrate metabolism in maize plants. As the root is where cytokinins, the plant hormons essential for maintaining photosynthetic structures, are synthesized, we assumed that the root status under stress caused by the herbicide sulphosate could be one of the factors of stability/sensitivity of photosynthesis/photosynthetic structures in plants exposed to this herbicide.U radu je razmatran uticaj herbicida sulfosata na rastenje, akumulaciju i preraspodelu suve mase, kao i fotosintezu biljaka kukuruza na kojima je vrÅ”ena manipulacija "proizvod-potroÅ”aÄ" odnosa na nivou korena. NaÄeno je da akumulacija suve mase znaÄajno KoreliÅ”e samo sa zapreminom i/ili udeonom suvom masom korena (Vr, RMR), a negativno znaÄajno sa udeonom suvom masom stabla (SMR) i (uglavnom) listova (LMR), Å”to je u skladu sa neravnomernom preraspodelom ugljenohidratnog metabolizma kod biljaka kukuruza. Poznato je da je koren mesto sinteze citokinina, biljnih hormona neophodnih u održavanju fotosintetskih struktura. PoÅ”to rezultati ukazuju na znaÄaj statusa korena u uslovima stresa izazvanim herbicidom sulfosatom, smatramo da isti može biti jedan od faktora stabilnosti /osetljivosti fotosinteze/ fotosintetskih struktura kod biljaka izloženih dejstvu pomenutog herbicida
Influence of supramolecular structure in the crystals on water/aromatic parallel alignment interactions
The parallel alignment interactions between water molecules and C-6-aryl groups in crystal structures and influence of supramolecular structures in crystals were studied by analyzing data in the Cambridge Structural Database (CSD). Analyses of crystal structures from the CSD reveal that the water/aromatic parallel alignment interactions, where the water molecule or one of its O-H bonds is parallel to the aromatic ring plane, are very frequent at large horizontal displacements. These orientations, observed in crystal structures, were compared with the results of ab initio calculations and explained by influence of supramolecular structures in crystals
A new association of ruderal weeds at PanÄevaÄki Rit in Serbia
A several-year study of distribution, phytocoenological differentiation, floristic composition and structure of ruderal flora and vegetation and relevant anthropogenic influence was conducted at PanÄevaÄki Rit in Serbia. Ten clearly distinctive ruderal communities were identified in the study, including the newly formed community Matricario-Helianthetum annuae. This community is a unique combination of transitional ruderal and agrestal vegetation developing spontaneously in close vicinity of intensively cultivated agricultural fields, in which sunflower (Helianthus annuus L.), an annual crop, appears and persists subspontaneously and often massively, rendering a physiognomical character to ruderal habitats in which ephemeral ruderal weed vegetation often develops, consisting predominantly of annual plants of Sisymbrion officinalis R.Tx., Lohm. et Prsg.1950
Novije moguÄnosti suzbijanja korova u pÅ”enici
Weed control is achieved only by utilizing herbicides and adequate agro-technical measures for wheat, with the use of herbicides against dominant types of weed in a rotating system of plant and vegetable cultures. The most certain solution to the problem of weeds in wheat is to stop sprouting and spreading of resistant weeds. The solution to the problem is facilitated by using a system of rotating plant types and the introduction of specific herbicides based on fluoroxipire, amidosulfurine, florasuluam and cinidon ethyl, depending on the appearance of problem weeds. Within the system of wheat management, regional and global models for controlling weeds for period over 5 years are formed, which implies fundamental changes to the introduction of novel technologies, transgenic cultivars and new herbicides.U radu je prikazan model suzbijanja korova u pÅ”enici i stepen efikasnosti i selektivnosti herbicida u sistem menadžmenta i integralne zaÅ”ite ratarskih useva na regionalnom i globalnom planu. Problem otpornih rezistentnih korova se pojednostavljuje i jednostavno reÅ”ava rotacijom useva i herbicida sa razliÄitim naÄinima delovanja, te uvoÄenjem odgovarajuÄih mera, novih specifiÄnih herbicida za suzbijanje ruralnih i problematiÄnih korova u pÅ”enici. Na taj naÄin se spreÄava nicanje i Å”irenje rezistentnih korova u sistemu smene useva pÅ”enice. Å”eÄerne repe, soje, kukuruza i soje
Supplementary data for the article: JanjiÄ, G. V.; MilosavljeviÄ, M. D.; VeljkoviÄ, D. Ž.; ZariÄ, S. D. Prediction of Strong O-H/M Hydrogen Bonding between Water and Square-Planar Ir and Rh Complexes. Physical Chemistry Chemical Physics 2017, 19 (13), 8657ā8660. https://doi.org/10.1039/c6cp08796e
Supplementary material for: [https://doi.org/10.1039/c6cp08796e]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2444]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3230
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