399 research outputs found
Molecularly imprinted conductive polymers for controlled trafficking of neurotransmitters at solid–liquid interfaces
We realize a molecularly imprinted polymer (MIP) which is imprinted with the
retinal neurotransmitter glutamate. The films prepared by electrochemical
deposition have a smooth surface with a granular morphology as observed using
an atomic force microscope. Multiple reflection attenuated total reflection
infrared (ATR-FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS)
are used to chemically confirm the imprint of a neurotransmitter in the MIP at
the solid–liquid and the solid–air interface, respectively. Fluorescence
spectroscopy using the dye fluorescamine is used to monitor the changes in
neurotransmitter concentration in various solvents induced by application of
voltage to the MIP. By controlling neurotransmitter trafficking across a
solid–liquid interface with voltage, we suggest the possibility of using such
a neurotransmitter imprinted MIP for chemical stimulation of retinal neurons.
The current state of the art approach to restore sight in certain cases of
blindness is the replacement of damaged photoreceptors by a subretinal implant
consisting of light-sensitive photodiodes. Thus a future perspective of our
work would be to chemically stimulate the neurons by replacing the photodiodes
in the subretinal implant by the neurotransmitter imprinted polymer film
Структура и свойства керамических композитов, модифицированных углеродными нанотрубками и нановолокнами Al2O3
Работа направлена на установление закономерности влияния вводимых добавок одностенных/многостенных УНТ и нановолокон Al2O3 на структуру, фазовый состав и физико-механические свойства композитов на основе оксидов алюминия и циркония. Показано, что использование УНТ и нановолокон Al2O3 при изготовлении композитов, может приводить к существенному повышению трещиностойкость керамических материалов. Кроме того, варьируя концентрацию вводимых добавок, можно получать оптимальные свойства керамических композитов для конкретных применений.The work is aimed at establishing the regularity of the influence of the introduced additives of single-wall/multi-walled CNTs and Al2O3 nanofibers on the structure, phase composition, and mechanical properties of composites based on alumina and zirconia. It is shown that the use of CNTs and Al2O3 nanofibers in the manufacture of composites can lead to a significant increase in the fracture toughness of ceramic materials. In addition, by varying the concentration of the added additives, it is possible to obtain the optimal properties of ceramic composites for specific applications
Universal and non-universal properties of cross-correlations in financial time series
We use methods of random matrix theory to analyze the cross-correlation
matrix C of price changes of the largest 1000 US stocks for the 2-year period
1994-95. We find that the statistics of most of the eigenvalues in the spectrum
of C agree with the predictions of random matrix theory, but there are
deviations for a few of the largest eigenvalues. We find that C has the
universal properties of the Gaussian orthogonal ensemble of random matrices.
Furthermore, we analyze the eigenvectors of C through their inverse
participation ratio and find eigenvectors with large inverse participation
ratios at both edges of the eigenvalue spectrum--a situation reminiscent of
results in localization theory.Comment: 14 pages, 3 figures, Revte
Update breast cancer 2020 part 5: moving therapies from advanced to early breast cancer patients
In recent years, significant progress has been made in new therapeutic approaches to breast cancer, particularly in patients with HER2-positive and HER2-negative/hormone receptor-positive (HR+) breast cancer. In the case of HER2-positive tumours, these approaches have included, in particular, treatment with pertuzumab, T-DM1, neratinib and, soon, also tucatinib and trastuzumab deruxtecan (neither of which has yet been authorised in Europe). In patients with HER2−/HR+ breast cancer, CDK4/6 inhibitors and the PIK3CA inhibitor alpelisib are of particular importance. Further novel therapies, such as Akt kinase inhibitors and oral SERDs (selective estrogen receptor down regulators), are already being investigated in ongoing clinical trials. These therapeutic agents are not only being introduced into curative, (neo-)adjuvant therapeutic settings for HER2-positive tumours; a first favourable study on abemaciclib as an adjuvant therapy has now also been published. In patients with triple-negative breast cancer, after many years of negative study results with the Trop-2 antibody drug conjugate (ADC) sacituzumab govitecan, a randomised study has been published that may represent a significant therapeutic advance. This review describes the latest developments in breast cancer subsequent to the ESMO Congress 2020
Overview of ImageCLEF 2018: Challenges, Datasets and Evaluation
This paper presents an overview of the ImageCLEF 2018 evaluation campaign, an event that was organized as part of the CLEF (Conference and Labs of the Evaluation Forum) Labs 2018. ImageCLEF is an ongoing initiative (it started in 2003) that promotes the evaluation of technologies for annotation, indexing and retrieval with the aim of providing information access to collections of images in various usage scenarios and domains. In 2018, the 16th edition of ImageCLEF ran three main tasks and a pilot task: (1) a caption prediction task that aims at predicting the caption of a figure from the biomedical literature based only on the figure image; (2) a tuberculosis task that aims at detecting the tuberculosis type, severity and drug resistance from CT (Computed Tomography) volumes of the lung; (3) a LifeLog task (videos, images and other sources) about daily activities understanding and moment retrieval, and (4) a pilot task on visual question answering where systems are tasked with answering medical questions. The strong participation, with over 100 research groups registering and 31 submitting results for the tasks, shows an increasing interest in this benchmarking campaign
Update breast cancer 2021 part 5 – advanced breast cancer
Despite the COVID 19 pandemic and mostly virtual congresses, innovation in the treatment of breast cancer patients continues at an unabated pace. This review summarises the current developments. Initial overall survival data for CDK4/6 inhibitor treatment in combination with an aromatase inhibitor as the first advanced line of therapy in treatment-naive postmenopausal patients have been published. Similarly, a trial comparing trastuzumab-deruxtecan versus trastuzumab-emtansine revealed a clear benefit regarding progression-free survival. Understanding of biomarkers making checkpoint inhibitor therapy particularly effective is increasing, and new compounds such as oral selective estrogen receptor destabilisers (SERDs) are entering clinical development and completing the first phase III trials
Update breast cancer 2021 part 4 – prevention and early stages
This past year has seen new and effective options for further improving treatment outcome in many patients with early-stage breast cancer. Patients with hormone receptor-positive disease benefited significantly from the addition of the CDK4/6 inhibitor abemaciclib to endocrine adjuvant therapy. In triple-negative disease, data were presented for two treatment regimens. Patients with advanced disease (stage 2 and 3) benefit from neoadjuvant treatment with the immune checkpoint inhibitor pembrolizumab in combination with standard chemotherapy, regardless of PD-L1 expression. When neoadjuvant therapy has failed to achieve the desired remission in BRCA1 and BRCA2 mutations, the administration of the PARP inhibitor olaparib has demonstrated an impressive response. Other data address translational issues in HER2-positive breast cancer and neoadjuvant therapy approaches with the oral SERD giredestrant and the PARP inhibitor talazoparib. This review presents and analyses the findings of this yearʼ s most important study outcomes
Update breast cancer 2022 part 4 – advanced-stage breast cancer
For the treatment of patients with advanced HER2-negative hormone receptor-positive breast cancer, several substances have been introduced into practice in recent years. In addition, other drugs are under development. A number of studies have been published over the past year which have shown either an advantage for progression-free survival or for overall survival. This review summarizes the latest results, which have been published at current congresses or in specialist journals, and classifies them in the clinical treatment context. In particular, the importance of therapy with CDK4/6 inhibitors – trastuzumab deruxtecan, sacituzumab govitecan and capivasertib – is discussed. For trastuzumab deruxtecan, an overall survival benefit in HER2-negative breast cancer with low HER2 expression (HER2-low expression) was reported in the Destiny-Breast-04 study. Similarly, there was an overall survival benefit in the FAKTION study with capivasertib. The lack of overall survival benefit for palbociclib in the first line of therapy raises the question of clinical classification
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