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521.
Arianna Secco Alessandro Tonin Aygul Rana Andres Jaramillo-Gonzalez Majid Khalili-Ardali Niels Birbaumer Ujwal Chaudhary 《Cognitive neurodynamics》2021,15(3):473
Persons with their eye closed and without any means of communication is said to be in a completely locked-in state (CLIS) while when they could still open their eyes actively or passively and have some means of communication are said to be in locked-in state (LIS). Two patients in CLIS without any means of communication, and one patient in the transition from LIS to CLIS with means of communication, who have Amyotrophic Lateral Sclerosis were followed at a regular interval for more than 1 year. During each visit, resting-state EEG was recorded before the brain–computer interface (BCI) based communication sessions. The resting-state EEG of the patients was analyzed to elucidate the evolution of their EEG spectrum over time with the disease’s progression to provide future BCI-research with the relevant information to classify changes in EEG evolution. Comparison of power spectral density (PSD) of these patients revealed a significant difference in the PSD’s of patients in CLIS without any means of communication and the patient in the transition from LIS to CLIS with means of communication. The EEG of patients without any means of communication is devoid of alpha, beta, and higher frequencies than the patient in transition who still had means of communication. The results show that the change in the EEG frequency spectrum may serve as an indicator of the communication ability of such patients.Electronic supplementary materialThe online version of this article (10.1007/s11571-020-09639-w) contains supplementary material, which is available to authorized users. 相似文献
522.
EU member states have set an ambitious goal of establishing additional protected areas (PAs) preserving 30 % of terrestrial land by 2030, specifying that additions should be of high ecological quality. A targeted selection of existing PA expansions into surroundings marginally fragmented by human infrastructure, may be an efficacious strategy to secure high ecological quality by maximizing PA area, accommodating species movement, and boosting climate change resilience. We used high-resolution data on effective mesh density, a metric measuring landscape fragmentation, in the vicinity of Natura 2000 PAs (N2k) to assess their potential for expansion. Our results show that contrary to most of Central Europe, mountainous and remote territories exhibit the lowest degree of fragmentation in N2k surroundings. Fragmentation in N2k surroundings is highly correlated with national population density, while economic wealth, measured by GDP per capita, plays a minor role. To address the long-standing dilemma of where scarce economic resources in nature conservation do the most-good, we conducted a country-level comparison between fragmentation in N2k surroundings and national expenditures on nature conservation relative to N2k area. Our results show a vast incongruity in resource availability for nature conservation among EU countries. Eastern European states, especially Romania, host underfunded N2k PAs while holding the highest potential for expanding N2k PAs into low fragmented lands. If protecting low fragmented lands is accepted as an efficacious strategy to meet EU biodiversity targets our results could be used to formulate pragmatic conservation decisions, while also ensuring high ecological quality of PA additions under climate change. 相似文献
523.
The Forest Stewardship Council developed the concept of High Conservation Values (HCVs) as a criteria in the forest certification process in order to promote sustainable forest management. It has six major components or values and component one and two of HCVs deal with the habitat for viable populations of “rare, endemic and threatened (RET) species” using the IUCN Red List category and other national / regional / local lists. But a consistent robust methodology for identification of these areas, does not exist. The present study tried to develop for the first time, a straight forward inclusive methodology for identification of HCVAs for the RET species on a spatio-temporal scale. A total of 50 RET and other significant species (32 flora, 10 fauna and 8 avifauna) were identified after a thorough literature review, field surveys and consultations with experts. Occurrence data of the selected species was collected from different secondary sources, field surveys, institutes and scientists who have worked on them. A 10 km grid-based approach and stratified random sampling was used for the primary GPS field surveys conducted during 2018–2019. MaxEnt species distribution model (SDM) software was used based on the occurrence data and environmental variables for identification of potential suitable habitats for the selected species. Linear support vector machine (LSVM) model was used for assessing the performance of the SDMs. The performance of each SDM has been validated through Cohen's Kappa (KAPPA), true skill statistic (TSS) and receiver operating characteristics (ROC) models. The proposed methodology addresses the urgent need for a holistic and robust set of techniques to apply the HCV toolkit. This is key to identify and map HCVAs for RET species at the landscape level and can be easily adapted to and adopted at the national, regional, state or local level in India. The methods offer an efficient, reliable approach for the application of the HCV concept, elsewhere in the world. 相似文献
524.
《Bioorganic & medicinal chemistry letters》2019,29(16):2094-2099
The death receptor CD95 (also known as Fas) induces apoptosis through protein/protein association and the formation of the death-inducing signaling complex. On the other hand, in certain biological conditions, this receptor recruits different proteins and triggers the formation of another complex designated motility-inducing signaling complex, which promotes cell migration and inflammation. This pathway relies on a short sequence of CD95, called calcium-inducing domain (CID), which interacts with the phospholipase PLCγ1.To better understand how CID/PLCγ1 interaction occurs, we synthesized different α-AA peptides mimicking CID. Some of these peptidomimetics are as potent as the natural peptide to disrupt the CID/PLCγ1 interaction and cell migration, and showed improved pharmacokinetic properties.We also generated biotinyl- and palmitoyl-labelled peptidomimetics, useful chemico-biological tools to further explore the pro-inflammatory signal of CD95, which plays an important role in the pathogenesis of lupus and other autoimmune diseases. 相似文献
525.
526.
ObjectiveRadioresistance of tumor cells is a major factor associated with failure of radiotherapy (RT). This study aimed to investigate the effect of BRCA1 knockdown on MDA-MB231 breast cancer cell radiosensitivity.Materials and methodsShort hairpin RNA (shRNA) was used to knockdown BRCA1 gene in MDA-MB231 cells. Cell viability and proliferative capacity were assessed by CCK-8 and colony formation assays, respectively. We established xenograft models in nude mice to evaluate tumor volume and tumor weight. The mice were imaged by 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) before and after RT to evaluate changes in maximum standardized uptake value (SUVmax) and tumor SUVmax/muscle SUVmax (TMR). Changes in HIF-1α, Glut-1 and Ki-67 were analyzed and the correlation between 18F-FDG uptake and tumor biology was analyzed.ResultsCompared with the control cells, RT significantly reduced cell viability and colony formation capacity in cells with the BRCA1 gene knockdown. In vivo assays showed that there was obvious delay in the tumor growth in the shBRCA1+RT group compared with the control group. 18F-FDG Micro PET/CT indicated a reduction in glucose metabolism in the shBRCA1+RT group, with statistically significant differences in both the SUVmax and TMR. The data showed the expression of HIF-1α, Glut-1 and Ki-67 was downregulated in the shBRCA1+RT group, and both SUVmax and TMR had significant correlation with tumor biology.ConclusionThese results demonstrated that BRCA1 knockdown improves the sensitivity of MDA-MB231 breast cancer cells to RT. In addition, 18F-FDG PET/CT imaging allows non-invasive analysis of tumor biology and assessment of radiosensitivity. 相似文献