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551.
Farid Madani Andrei Moroianu Mihaela Pilca 《Annals of Global Analysis and Geometry》2017,51(4):401-417
We study compact toric strict locally conformally Kähler manifolds. We show that the Kodaira dimension of the underlying complex manifold is \(-\infty \), and that the only compact complex surfaces admitting toric strict locally conformally Kähler metrics are the diagonal Hopf surfaces. We also show that every toric Vaisman manifold has lcK rank 1 and is isomorphic to the mapping torus of an automorphism of a toric compact Sasakian manifold. 相似文献
552.
Mihaela Stoica D. Apostol Ileana Apostol Doina Crǎciun Al. Hening I.N. Mihǎilescu 《Optics Communications》1984,52(1):5-9
A complete setup for pulsed CO2 laser interferometry is described. The relative advantages and limits of different recording techniques of the interference pattern in 10.6 μm laser light are analysed. Preliminary recordings of the interference pattern in the case of early evolution stages of an air breakdown plasma in front of a solid target are given. 相似文献
553.
This article is concerned with in?nite depth gravity water waves in two space dimensions. We consider this system expressed in position-velocity potential holomorphic coordinates. Our goal is to study this problem with small wave packet data, and to show that this is well approximated by the cubic nonlinear Schr¨odinger equation(NLS) on the natural cubic time scale. 相似文献
554.
Yara Santiago de Oliveira Wendell Saraiva Costa Poliana Ferreira Borges Maria Silmara Alves de Santana Alejandro Pedro Ayala 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(5):483-495
The use of supramolecular synthons as a strategy to control crystalline structure is a crucial factor in developing new solid forms with physicochemical properties optimized by design. However, to achieve this objective, it is necessary to understand the intermolecular interactions in the context of crystal packing. The feasibility of a given synthon depends on its flexibility to combine the drug with a variety of coformers. In the present work, the imidazole–hydroxy synthon is investigated using as the target molecule benzoylmetronidazole [BZMD; systematic name 2‐(2‐methyl‐5‐nitro‐1H‐imidazol‐1‐yl)ethyl benzoate], whose imidazole group seems to be a suitable acceptor for hydrogen bonds. Thus, coformers with carboxylic acid and phenol groups were chosen. According to the availability of binding sites presented in the coformer, and considering the proposed synthon and hydrogen‐bond complementarity as major factors, different drug–coformer stoichiometric ratios were explored (1:1, 2:1 and 3:1). Thirteen new solid forms (two salts and eleven cocrystals) were produced, namely BZMD–benzoic acid (1/1), C13H13N3O4·C7H6O2, BZMD–β‐naphthol (1/1), C13H13N3O4·C10H8O, BZMD–4‐methoxybenzoic acid (1/1), C13H13N3O4·C8H8O3, BZMD–3,5‐dinitrobenzoic acid (1/1), C13H13N3O4·C7H4N2O6, BZMD–3‐aminobenzoic acid (1/1), C13H13N3O4·C7H7NO2, BZMD–salicylic acid (1/1), C13H13N3O4·C7H6O3, BZMD–maleic acid (1/1) {as the salt 1‐[2‐(benzoyloxy)ethyl]‐2‐methyl‐5‐nitro‐1H‐imidazol‐3‐ium 3‐carboxyprop‐2‐enoate}, C13H14N3O4+·C4H3O4?, BZMD–isophthalic acid (1/1), C13H13N3O4·C8H6O4, BZMD–resorcinol (2/1), 2C13H13N3O4·C6H6O2, BZMD–fumaric acid (2/1), C13H13N3O4·0.5C4H4O4, BZMD–malonic acid (2/1), 2C13H13N3O4·C3H2O4, BZMD–2,6‐dihydroxybenzoic acid (1/1) {as the salt 1‐[2‐(benzoyloxy)ethyl]‐2‐methyl‐5‐nitro‐1H‐imidazol‐3‐ium 2,6‐dihydroxybenzoate}, C13H14N3O4+·C7H5O4?, and BZMD–3,5‐dihydroxybenzoic acid (3/1), 3C13H13N3O4·C7H6O4, and their crystalline structures elucidated, confirming the robustness of the selected synthon. 相似文献
555.
Dushanthi S. Dissanayake Samodha S. Gunathilake Chinthaka M. Udamulle Gedara Jia Du Sang Ha Yoo Youngmin Lee Qing Wang Enrique D. Gomez Michael C. Biewer Mihaela C. Stefan 《Journal of polymer science. Part A, Polymer chemistry》2019,57(10):1079-1086
Synthesis of two conducting polymers containing 3‐hexylthiophene and 3‐[2‐(2‐(2‐methoxyethoxy)ethoxy)ethoxy]thiophene is demonstrated. In thin‐film transistors, the high‐molecular‐weight polymer shows an average mobility of 4.2 × 10?4 cm2 V?1 s?1. Most importantly, the polymers have high conductivity upon doping with iodine and also have high stability in the doped state with high conductivities measured even after 1 month. Furthermore, the doping causes transparency to thin films of the polymer and the films are resistant to common organic solvents. All these properties indicate a great potential for the iodine‐doped polymer to be used as an alternative to commercially available poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate). © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 1079–1086 相似文献
556.
557.
Daniela-Simina Stefan Mariana Popescu Cristina-Mihaela Luntraru Alexandru Suciu Mihai Belcu Lucia-Elena Ionescu Mihaela Popescu Petrica Iancu Mircea Stefan 《Molecules (Basel, Switzerland)》2022,27(22)
Essential oils were obtained from different parts of Agastache foeniculum (Lophanthus anisatus) plants by means of extraction: green extraction using hydro-distillation (HD) and bio-solvent distillation, BiAD, discontinuous distillation, and supercritical fluid extraction, in two stages: (1) with CO2, and (2) with CO2 and ethanol co-solvent. The extraction yields were determined. The yield values varied for different parts of the plant, as well as the method of extraction. Thus, they had the values of 0.62 ± 0.020 and 0.92 ± 0.015 g/100 g for the samples from the whole aerial plant, 0.75 ± 0.008 and 1.06 ± 0.005 g/100 g for the samples of leaves, and 1.22 ± 0.011 and 1.60 ± 0.049 g/100 g for the samples of flowers for HD and BiAD, respectively. The yield values for supercritical fluid extraction were of 0.94 ± 0.010 and 0.32 ± 0.007 g/100 g for the samples of whole aerial plant, 0.9 ± 0.010 and 1.14 ± 0.008 g/100 g for the samples of leaves, and 1.94 ± 0.030 and 0.57 ± 0.003 g/100 g for the samples of flowers, in the first and second stages, respectively. The main components of Lophanthus anisatus were identified as: estragon, limonene, eugenol, chavicol, benzaldehyde, and pentanol. The essential oil from Agatache foeniculum has antimicrobial effects against Staphylococcus aureus, the Escherichia coli and Pseudomonas aeruginosa. Acclimatization of Lophantus anisatus in Romania gives it special qualities by concentrating components such as: estragole over 93%, limonene over 8%, especially in flowers; and chavicol over 14%, estragole over 30%, eugenol and derivatives (methoxy eugenol, methyl eugenol, etc.) over 30% and phenyl ether alcohol over 20% in leaves. As a result of the research carried out, it was proven that Lophanthus anisatus can be used as a medicinal plant for many diseases, it can be used as a spice and preservative for various foods, etc. 相似文献
558.
Laura-Ileana Socea Stefania-Felicia Barbuceanu Elena Mihaela Pahontu Alexandru-Claudiu Dumitru George Mihai Nitulescu Roxana Corina Sfetea Theodora-Venera Apostol 《Molecules (Basel, Switzerland)》2022,27(24)
Due to the structure of acylhydrazones both by the pharmacophore –CO–NH–N= group and by the different substituents present in the molecules of compounds of this class, various pharmacological activities were reported, including antitumor, antimicrobial, antiviral, antiparasitic, anti-inflammatory, immunomodulatory, antiedematous, antiglaucomatous, antidiabetic, antioxidant, and actions on the central nervous system and on the cardiovascular system. This fragment is found in the structure of several drugs used in the therapy of some diseases that are at the top of public health problems, like microbial infections and cardiovascular diseases. Moreover, the acylhydrazone moiety is present in the structure of some compounds with possible applications in the treatment of other different pathologies, such as schizophrenia, Parkinson’s disease, Alzheimer’s disease, and Huntington’s disease. Considering these aspects, we consider that a study of the literature data regarding the structural and biological properties of these compounds is useful. 相似文献
559.
Ciro Menale Gaia Tabacco Anda Mihaela Naciu Maria Lucia Schiavone Francesca Cannata Emanuela Morenghi Cristina Sobacchi Andrea Palermo 《Molecules (Basel, Switzerland)》2022,27(12)
The dipeptidyl peptidase 3 (Dpp3) is a ubiquitous zinc-dependent aminopeptidase, participating in the activation or degradation of signaling peptides and in the Keap1–Nrf2 antioxidant pathway. The absence of Dpp3 in the Dpp3 knockout mouse model causes increased osteoclast activity, altered osteogenic function, sustained oxidative stress in the bone tissue, and bone loss. We aimed to assess the association of Dpp3 activity with bone fragility in postmenopausal osteoporosis and the impact of denosumab on enzymatic activity. We conducted a two-phase study including 69 postmenopausal women with severe osteoporosis and 36 postmenopausal women without osteometabolic conditions, as controls (cross-sectional phase). Subjects with severe osteoporosis were assessed at baseline and 14 days after the first denosumab administration (prospective phase). The results showed significant reduction in serum Dpp3 activity (expressed as nmoles of formed product/mg proteins/min) in patients vs. controls (0.791 ± 0.232 vs. 1.195 ± 0.338; p < 0.001), and significant association with bone mass at the femoral neck (r = 0.28, p = 0.02) in patients prior to treatment. We found a negative correlation between C-terminal telopeptide (CTX) or N-terminal pro-peptide of type 1 procollagen (P1NP) levels and Dpp3 activity (respectively, r = −0.29, p = 0.012; and r = −0.2572, p = 0.033). Dpp3 activity did not change after denosumab injection. Our findings support a critical role played by Dpp3 in bone homeostasis as a potential bone protective factor. Additional clinical studies in larger cohorts might explore the implementation of Dpp3 assessment as a biomarker of bone health status. 相似文献
560.
The construction of the human eyeball has characteristics of the composite structure considering the optically transparent media (cornea, crystalline) that participate in the formation of images on the surface of the retina. Both the cornea and the crystalline are formed by thin cellular layers that behave like structures composed of elastic curved plates. The first part of the article presents the theoretical aspects that are the basis of the biomechanical approach of this ensemble. In the second part, the aspects of the modeling of the optical behavior of the eyeball and elasticity of the lens are presented. The final part of the article presents the conclusions regarding the behavior of the composite structure of the ocular globe from a biomechanical and optical point of view. 相似文献