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Jakub Hrubý Vinicius T. Santana Dmytro Kostiuk Martin Bou
ek Samuel Lenz Michal Kern Peter iffalovi
Joris van Slageren Petr Neugebauer 《RSC advances》2019,9(42):24066
The scalability and stability of molecular qubits deposited on surfaces is a crucial step for incorporating them into upcoming electronic devices. Herein, we report on the preparation and characterisation of a molecular quantum bit, copper(ii)dibenzoylmethane [Cu(dbm)2], deposited by a modified Langmuir–Schaefer (LS) technique onto a graphene-based substrate. A double LS deposition was used for the preparation of a few-layer-graphene (FLG) on a Si/SiO2 substrate with subsequent deposition of the molecules. Magnetic properties were probed by high-frequency electron spin resonance (HF-ESR) spectroscopy and found maintained after deposition. Additional spectroscopic and imaging techniques, such as Raman spectroscopy (RS), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscopy (SEM) were performed to characterise the deposited sample. Our approach demonstrated the possibility to utilise a controlled wet-chemistry protocol to prepare an array of potential quantum bits on a disordered graphene-based substrate. The deployed spectroscopic techniques showed unambiguously the robustness of our studied system with a potential to fabricate large-scale, intact, and stable quantum bits.Graphene-based hybrid material with array of copper(ii)-based quantum bits was prepared by a wet-chemistry protocol and characterised by HF-ESR, XPS, Raman, and AFM. 相似文献
75.
Petr Bob Robert Roman Miroslav Svetlak Miloslav Kukleta Jan Chladek Milan Brazdil 《Medicine》2014,93(23)
Recent findings suggest that neural complexity reflecting a number of independent processes in the brain may characterize typical changes during epileptic seizures and may enable to describe preictal dynamics. With respect to previously reported findings suggesting specific changes in neural complexity during preictal period, we have used measure of pointwise correlation dimension (PD2) as a sensitive indicator of nonstationary changes in complexity of the electroencephalogram (EEG) signal. Although this measure of complexity in epileptic patients was previously reported by Feucht et al (Applications of correlation dimension and pointwise dimension for non-linear topographical analysis of focal onset seizures. Med Biol Comput. 1999;37:208–217), it was not used to study changes in preictal dynamics. With this aim to study preictal changes of EEG complexity, we have examined signals from 11 multicontact depth (intracerebral) EEG electrodes located in 108 cortical and subcortical brain sites, and from 3 scalp EEG electrodes in a patient with intractable epilepsy, who underwent preoperative evaluation before epilepsy surgery. From those 108 EEG contacts, records related to 44 electrode contacts implanted into lesional structures and white matter were not included into the experimental analysis.The results show that in comparison to interictal period (at about 8–6 minutes before seizure onset), there was a statistically significant decrease in PD2 complexity in the preictal period at about 2 minutes before seizure onset in all 64 intracranial channels localized in various brain sites that were included into the analysis and in 3 scalp EEG channels as well. Presented results suggest that using PD2 in EEG analysis may have significant implications for research of preictal dynamics and prediction of epileptic seizures. 相似文献
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Radek Jorda Jana Navrátilová Zlata Hušková Eva Schütznerová Petr Cankař Miroslav Strnad Vladimír Kryštof 《Chemical biology & drug design》2014,84(4):402-408
Inhibitors of cyclin‐dependent kinases 9 have been developed as potential anticancer drugs for the treatment of multiple myeloma. We have previously prepared a library of arylazo‐3,5‐diaminopyrazole inhibitors of CDKs. Here, we describe a novel member, AAP1742 (CDK9 inhibition with IC50 = 0.28 μm ), that reduces the viability of multiple myeloma cell lines in low micromolar concentrations. Consistent with inhibition of CDK9, AAP1742 decreases the phosphorylation of RNA polymerase II and inhibits mRNA synthesis of anti‐apoptotic proteins Mcl‐1, Bcl‐2, and XIAP, followed by apoptosis in the RPMI‐8226 cell line in a dose‐ and a time‐dependent manner. These results are consistent with the biochemical profile of AAP1742 and further suggest cellular inhibition of CDK9 as a possible target for anticancer drugs. 相似文献
78.
Magda Vytrisalova Leos Fuksa Vladimir Palicka Svatopluk Byma Sarka Blazkova Jan Stepan Tereza Hendrychova Jiri Vlcek Petr Pavek 《Central European Journal of Medicine》2014,9(5):687-693
Rationale and objectives
General practitioners (GPs) play an important role in management of patients at risk of osteoporosis (OP). The objectives were to assess (1) knowledge about OP and use of OP clinical guideline in comparison with other information sources and (2) association between the use of individual information sources and knowledge and self-reported quality of care among GPs.Methods
Survey among random sample of Czech GPs was performed to find out their attitudes and role in OP management. The return rate of the postal questionnaire was 38% (525 respondents). Quality of care was assessed using three indicators: suspicion on OP, referral to the specialist and initial check-up.Results
Respondents (median age 52 years, 59% women) had a very good knowledge of several risk factors, while others, namely low body mass index, history of hip fracture in mother and smoking were perceived as risk factors by only 40%, 45% and 55% of respondents, respectively. 10% of GPs stated the correct answer regarding daily calcium intake recommended for postmenopausal women. The OP guideline was considered accessible by 83% of respondents and used repeatedly by 54%. Use of the guideline correlated positively with knowledge score (P < 0.001), while use of each individual other source of information did not. Use of the guideline correlated with all three indicators of quality of care. Use of each other information source correlated only with a maximum of two indicators.Conclusion
We identified areas of insufficient knowledge that should be targeted in educational activities for GPs. It is recommended to further motivate GPs to use their clinical guidelines regularly. 相似文献79.
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Martina Lengerova Zdenek Racil Kristyna Hrncirova Iva Kocmanova Pavlina Volfova Dita Ricna Petr Bejdak Mojmir Moulis Zdenek Pavlovsky Barbora Weinbergerova Martina Toskova Jiri Mayer 《Journal of clinical microbiology》2014,52(8):2824-2828
Rapid differential diagnostics of pulmonary infiltrates suspected of invasive fungal disease in an immunocompromised host and early initiation of effective antifungal therapy are crucial for patient outcomes. There are no serological tests available to detect mucormycetes; therefore, PCR-based methods are highly suitable. We validated our previously published PCR followed by high-resolution melt analysis (PCR/HRMA) to detect Rhizopus spp., Rhizomucor pusillus, Lichtheimia corymbifera, and Mucor spp. in bronchoalveolar lavage (BAL) samples from immunocompromised patients who were at risk of invasive fungal disease. All PCR/HRMA-positive samples were retested using novel real-time quantitative PCR (RQ PCR) assays specific to the species identified. In total, between January 2009 and December 2012 we analyzed 99 BAL samples from 86 patients with pulmonary abnormalities using PCR/HRMA. Ninety (91%) BAL samples were negative, and 9 (9%) samples were positive. The sensitivity and specificity of PCR/HRMA were 100% and 93%, respectively. By combining the positive results of PCR/HRMA with positive RQ PCR results, the specificity was raised to 98%. PCR/HRMA, due to its high negative predictive value (99%), represents a fast and reliable tool for routine BAL sample screening for the differential diagnosis of pulmonary infiltrates in immunocompromised patients for the four most clinically important mucormycetes. 相似文献