The behavior of 1,1′-bi-2-naphthol (BINOL) in variety of (super)acid media has been studied by NMR. The results are combined with the theoretical (DFT) study of the role of mono- and diprotonated ...forms of BINOL in the acid-catalyzed atropisomerization of this compound. It is demonstrated that the process of enantiomeric configuration exchange proceeds mainly via internal rotation around the C1(sp3)–C1′(sp3) bond in intermediates such as C1-monoprotonated keto or C1,C1′-diprotonated forms of BINOL, depending on the acidity level.
Важной технологией для неразрушающего мониторинга пигментного состава растений, который тесно связан с их физиологическим состоянием или заражением патогенами, является дистанционное
зондирование при ...помощи гиперспектральных камер. В работе представлен опыт применения мобильной
гиперспектральной камеры Specim IQ для исследований заболевания проростков четырех сортов пшеницы
обыкновенной корневой гнилью (возбудитель – гриб Bipolaris sorokiniana Shoem.), а также для анализа мякоти клубней картофеля 82 линий и сортов. Для проростков были получены спектральные характеристики
и по данным определены наиболее информативные спектральные признаки (индексы) для обнаружения
корневой гнили. У проростков контрольных вариантов в видимой части спектра наблюдается возрастание
отражательной способности с небольшим пиком в зеленой области (около 550 нм), затем идет понижение
из-за поглощения света пигментами растений с экстремумом при длине волны около 680 нм. Анализ гистограмм значений вегетационных индексов показал, что индексы TVI и MCARI наиболее информативны для
обнаружения патогена на проростках пшеницы по данным гиперспектральной съемки. Для образцов картофеля были выявлены участки спектра, соответствующие
локальным максимумам и минимумам отражения. Показано, что спектры сортов картофеля имеют наибольшие различия в области длин волн 900–1000,
400–450 нм, что в первом случае может быть связано с уровнем содержания воды, а во втором – с формированием в клубнях меланина. По характеристикам спектра исследованные образцы разделились на три
группы, каждая
из которых содержит повышенные либо пониженные уровни интенсивности для указанных
участков спектра. Кроме того, для ряда сортов были установлены минимумы в спектрах отражения, соответствующих хлорофиллу a. Результаты демонстрируют возможности камеры Specim IQ для проведения исследований гиперспектрального анализа растительных объектов.
By the example of 4-dimethylaminopyridine and some of its derivatives taken as model nitrogen heterocycles with several basic centers, the correlation of the parameters of the NMR spectra with the ...direction (regioselectivity) and multiplicity of protonation of these compounds in CF
3
COOH–CD
2
Cl
2
, TfOH–CD
2
Cl
2
, and FSO
3
H–SbF
5
acid systems was studied. The established dependence of the spectral characteristics on the value of the introduced positive charge will be useful in studying the reactivity of similar heterocyclic systems in the presence of acidic agents.
A method for automation of imago quantifying and fecundity assessment in Drosophila with the use of mobile devices running Android operating system is proposed. The traditional manual method of ...counting the progeny takes a long time and limits the opportunity of making large-scale experiments. Thus, the development of computerized methods that would allow us to automatically make a quantitative estimate of D. melanogaster fecundity is an urgent requirement. We offer a modification of the mobile application SeedCounter that analyzes images of objects placed on a standard sheet of paper for an automatic calculation of D. melanogaster offspring or quantification of adult flies in any other kind of experiment. The relative average error in estimates of the number of flies by mobile app is about 2% in comparison with the manual counting and the processing time is 6 times shorter. Study of the effects of imaging conditions on accuracy of flies counting showed that lighting conditions do not significantly affect this parameter, and higher accuracy can be achieved using high-resolution smartphone cameras (8 Mpx and more). These results indicate the high accuracy and efficiency of the method suggested.
Seed storage is important to farmers, breeders and for germplasm preservation. During storage, seeds accumulate damage at the structural and metabolic level, which disrupt their function and reduce ...resistance to adverse external conditions. In this regard, issues related to seed aging prove to be relevant for maintaining the viability of genetic collections. We analyzed morphological characteristics of grains and their coat color for 44 recombinant inbred lines (RILs) of bread wheat grown in four different seasons, 2003, 2004, 2009 and 2014. Our investigations were performed in 2020. For 19 RILs from the same seasons germination was evaluated. Our results demonstrate that genotype significantly affects the variability of all seed traits, and the year of harvesting affects about 80% of them (including all the traits of shape and size). To identify the trend between changes in grain characteristics and harvesting year, we estimated correlation coefficients between them. No significant trend was detected for the grain shape/size traits, while 90% of the color traits demonstrated such a trend. The most significant negative correlations were found between the harvesting year and the traits of grain redness: the greater the storage time, the more intensive is red color component for the grains. At the same time, it was shown that grains of longer storage time (earlier harvesting year) have lighter coat. Analysis of linear correlations between germination of wheat seeds of different genotypes and harvesting years and their seed traits revealed a negative linear relationship between the red component of coat color and germination: the redder the grains, the lower their germination rate. The results obtained demonstrate manifestations of metabolic changes in the coat of grains associated with storage time and their relationship with a decrease of seed viability.
We previously showed that monoterpenoid (1R,2R,6S)-3-methyl-6-(prop-1-en-2-yl)cyclohex-3-ene-1,2-diol 1 alleviates motor manifestations of Parkinson’s disease in animal models. In the present study, ...we designed and synthesized monoepoxides of (1R,2R,6S)-3-methyl-6-(prop-1-en-2-yl)cyclohex-3-ene-1,2-diol 1 and evaluated their biological activity in the MPTP mouse model of Parkinson’s disease. We also assessed the ability of these compounds to penetrate the blood–brain barrier (BBB). According to these data, we chose epoxide 4, which potently restored the locomotor activity in MPTP-treated mice and efficiently penetrated the BBB, to further explore its potential mechanism of action. Epoxide 4 was found to robustly promote the survival of cultured dopamine neurons, protect dopamine neurons against toxin-induced degeneration, and trigger the mitogen-activated protein kinase (MAPK) signaling cascade in cells of neuronal origin. Meanwhile, neither the survival-promoting effect nor MAPK activation was observed in non-neuronal cells treated with epoxide 4. In the MPTP mouse model of Parkinson’s disease, compound 4 increased the density of dopamine neuron fibers in the striatum, which can highlight its potential to stimulate striatal reinnervation and thus halt disease progression. Taken together, these data indicate that epoxide 4 can be a promising compound for further development, not only as a symptomatic but also as a neuroprotective and neurorestorative drug for Parkinson’s disease.
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