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Abstract Background Residual image noise is substantial in positron emission tomography (PET) and one of the factors limiting lesion detection, quantification, and overall image quality. Thus, improving noise reduction remains of considerable interest. This is especially true for respiratory-gated PET investigations. The only broadly used approach for noise reduction in PET imaging has been the application of low-pass filters, usually Gaussians, which however leads to loss of spatial resolution and increased partial volume effects affecting detectability of small lesions and quantitative data evaluation. The bilateral filter (BF) — a locally adaptive image filter — allows to reduce image noise while preserving well defined object edges but manual optimization of the filter parameters for a given PET scan can be tedious and time-consuming, hampering its clinical use. In this work we have investigated to what extent a suitable deep learning based approach can resolve this issue by training a suitable network with the target of reproducing the results of manually adjusted case-specific bilateral filtering. Methods Altogether, 69 respiratory-gated clinical PET/CT scans with three different tracers ( $$[^{18}\text {F}]$$ [ 18 F ] FDG, $$[^{18}\text {F}]$$ [ 18 F ] L-DOPA, $$[^{68}\text {Ga}]$$ [ 68 Ga ] DOTATATE) were used for the present investigation. Prior to data processing, the gated data sets were split, resulting in a total of 552 single-gate image volumes. For each of these image volumes, four 3D ROIs were delineated: one ROI for image noise assessment and three ROIs for focal uptake (e.g. tumor lesions) measurements at different target/background contrast levels. An automated procedure was used to perform a brute force search of the two-dimensional BF parameter space for each data set to identify the “optimal” filter parameters to generate user-approved ground truth input data consisting of pairs of original and optimally BF filtered images. For reproducing the optimal BF filtering, we employed a modified 3D U-Net CNN incorporating residual learning principle. The network training and evaluation was performed using a 5-fold cross-validation scheme. The influence of filtering on lesion SUV quantification and image noise level was assessed by calculating absolute and fractional differences between the CNN, manual BF, or original (STD) data sets in the previously defined ROIs. Results The automated procedure used for filter parameter determination chose adequate filter parameters for the majority of the data sets with only 19 patient data sets requiring manual tuning. Evaluation of the focal uptake ROIs revealed that CNN as well as BF based filtering essentially maintain the focal $$\text {SUV}_\text {max}$$ SUV max values of the unfiltered images with a low mean ± SD difference of $$\delta \text {SUV}_\text {max}^{\text {CNN},\text {STD}}$$ δ SUV max CNN , STD = (−3.9 ± 5.2)% and $$\delta \text {SUV}_\text {max}^{\text {BF},\text {STD}}$$ δ SUV max BF , STD = (−4.4 ± 5.3)%. Regarding relative performance of CNN versus BF, both methods lead to very similar $$\text {SUV}_\text {max}$$ SUV max values in the vast majority of cases with an overall average difference of $$\delta \text {SUV}_\text {max}^{\text {CNN},\text {BF}}$$ δ SUV max CNN , BF = (0.5 ± 4.8)%. Evaluation of the noise properties showed that CNN filtering mostly satisfactorily reproduces the noise level and characteristics of BF with $$\delta \text {Noise}^{\text {CNN},\text {BF}}$$ δ Noise CNN , BF = (5.6 ± 10.5)%. No significant tracer dependent differences between CNN and BF were observed. Conclusions Our results show that a neural network based denoising can reproduce the results of a case by case optimized BF in a fully automated way. Apart from rare cases it led to images of practically identical quality regarding noise level, edge preservation, and signal recovery. We believe such a network might proof especially useful in the context of improved motion correction of respiratory-gated PET studies but could also help to establish BF-equivalent edge-preserving CNN filtering in clinical PET since it obviates time consuming manual BF parameter tuning.

Introduction Loss of blood-brain barrier (BBB) integrity is hypothesised to be one of the earliest microvascular signs of Alzheimer’s disease (AD). Existing BBB integrity imaging methods involve contrast agents or ionising radiation, and pose limitations in terms of cost and logistics. Arterial spin labelling (ASL) perfusion MRI has been recently adapted to map the BBB permeability non-invasively. The DEveloping BBB-ASL as a non-Invasive Early biomarker (DEBBIE) consortium aims to develop this modified ASL-MRI technique for patient-specific and robust BBB permeability assessments. This article outlines the study design of the DEBBIE cohorts focused on investigating the potential of BBB-ASL as an early biomarker for AD (DEBBIE-AD).Methods and analysis DEBBIE-AD consists of a multicohort study enrolling participants with subjective cognitive decline, mild cognitive impairment and AD, as well as age-matched healthy controls, from 13 cohorts. The precision and accuracy of BBB-ASL will be evaluated in healthy participants. The clinical value of BBB-ASL will be evaluated by comparing results with both established and novel AD biomarkers. The DEBBIE-AD study aims to provide evidence of the ability of BBB-ASL to measure BBB permeability and demonstrate its utility in AD and AD-related pathologies.Ethics and dissemination Ethics approval was obtained for 10 cohorts, and is pending for 3 cohorts. The results of the main trial and each of the secondary endpoints will be submitted for publication in a peer-reviewed journal.

Introduction: Mid-life cardiovascular and late-life structural cerebrovascular pathology play a major role in accelerating cognitive decline in normal aging and dementia. Cerebral blood flow (CBF) may be a critical intermediate biomarker of future cognitive decline, however our understanding of normal CBF variability and its relation with mid-life cardiovascular and late-life structural cerebrovascular parameters is limited. The MRC National Survey of Health and Development neuroimaging sub-study ‘Insight 46’ provides a unique opportunity to study the effects of cardiovascular and cerebrovascular health on CBF in a cohort with a fixed chronological age. We explored associations of life-long cardiovascular parameters and WMH volume with ASL MRI CBF in this cognitively healthy population-based sample. Methods: 3D T1-weighted, FLAIR, and pseudo-continuous ASL (labeling duration = 1800ms; post-labelling delay = 1800ms) data (3T) were acquired in 295 participants (Table 1). Clinical data included systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), pulse pressure (PP), and the Framingham Risk Score (FRS). MRI scans were processed with ExploreASL. Grey matter (GM), white matter (WM) and white matter hyperintensity (WMH) volume were segmented from the T1w and FLAIR images. ASL- derived partial volume-corrected CBF and the spatial coefficient of variation (sCoV) were obtained in whole-brain GM and WM. Linear regression models examined associations between life-long cardiovascular health (ages 43, 53, 60-64, 69, and 69-71 years), ASL metrics (at 69-71 years), and WMH load (at 69-71 years). Models were corrected for sex, and sex interactions were tested if applicable. Results: While mid-life cardiovascular parameters were associated with late-life sCoV and CBF, the strongest associations were seen at 69-71 years. At this time point, higher SBP and MAP were associated with lower GM CBF in men (1A-B, β=-0.16,-0.28) and relatively stable GM CBF in women (1A-B, β=0.02,-0.02); higher DBP was associated with lower GM CBF (β=-0.18). Higher WMH volume was related to higher GM and WM CBF (2A-B, β=2.04,1.45), and lower GM and WM sCoV (2C-D, β=-0.04,0.05). Discussion: These sex-dependent associations encourage further investigation into the potential mediatory role of CBF between mid-life cardiovascular and late-life structural decline of cerebrovascular health, leading to cognitivexxxxx

Introduction: The inadequate blood supply to the brain is known predictive of cognitive decline. However, it remains unclear if diet patterns affect the cerebral blood flow (CBF) and contribute to cognitive impairment. This study aims to examine association between diet and CBF as well as cognition in an Asian population. Methods: The Neurological Biomarkers of Blood, MRI and Cognition study recruits Singaporeans aged 45-85 and collects their dietary habits using a 37-item diet screener. Dietary Approaches to Stop Hypertension (DASH) score (range 7-35) was calculated with a higher score indicating better compliance. Included food items were whole grain, vegetable, nuts and legumes, fruits, dairy, sugar-sweetened beverages, red and processed meat. Red and processed meat consumption was divided into levels one to four for amounts of above 0.71, (0.36, 0.71], (0.14, 0.36] and [0, 0.14] serving/day. Cognitive function was assessed using the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) and the scores were log-transformed. Participants showing signs of possible cognitive impairment underwent a 3T brain MRI scan, where the arterial spin labeling (ASL) technique was employed to measure CBF in both white and gray matter. After removing extreme values, CBF measurements are standardized by the intracranial brain volume and then Z-transformed by standard deviation. Results: The study included 243 participants, of whom 72 had ASL images. Participants had a mean (SD) CBF of 17.4 (8.7) and 34.2 (7.9) mL/100g/min in white and gray matter. After adjusting for age and gender, each 10-point increment in the DASH score showed non-significantly higher CBF in white matter (β = 0.18, 95%CI -0.34, 0.70) and gray matter (β=0.07, 95%CI -0.43, 0.58). Compared with the first level of meat intake, the second level was associated with higher CBF in gray matter (β = 0.61, 95%CI 0.03, 1.19) and higher log-MoCA (β = 0.45, 95%CI 0.07, 0.84). The third level of meat intake was associated with a higher CBF (β = 0.76, 95%CI 0.09, 1.44). Discussion: Optimal intake of red and processed meat but not overall DASH score was found to be associated with increased blood supply to brain as well as better cognitive performance.

Introduction: Arterial spin labeling (ASL) MRI, a non-invasive technique for imaging perfusion, now allows studying BBB permeability. The DEveloping BBB-ASL as a non-Invasive Early biomarker of Alzheimer's Disease (DEBBIE-AD) multi-cohort study integrates this modified BBB-ASL technique in several healthy and diseased populations (Table 1) to study methodological and clinical research questions (Table 2) on the ability of BBB-ASL as an early AD biomarker. Methods: DEBBIE-AD will enroll various cohorts with subjective cognitive decline, mild cognitive impairment, and AD dementia, as well as age-matched healthy controls, at seven sites (Table 1). Our newly developed BBB-ASL sequence — implemented with the vendor-independent MRI framework gammaSTAR — will be added to multiple MRI protocols. The BBB-ASL sequence combines time-encoded multi-post labeling delay pseudo-continuous ASL with a multi-echo 3D GRASE readout, allowing estimating CBF, ATT, and the BBB time of exchange (Tex). Data analyses will be conducted using ExploreASL. Beyond MRI standard sequences, including T1w, T2w, FLAIR, DWI, the DEBBIE clinical outcomes include amyloid-PET and blood and CSF fluid biomarkers (Table 1). Expected Results: Preliminary testing of the BBB-ASL has been conducted on 3T systems (different Siemens Heathineers scanners) in different cohorts at multiple sites. Data processing with ExploreASL includes FSL-FABBER4 for quantification, allowing harmonized image processing. An example of the mean and standard deviation Tex maps of two DEBBIE cohorts is shown in Figure 1 to illustrate the similarities of the Tex patterns from two cohorts of similar-aged healthy adults from different sites. Discussion: The DEBBIE-AD study aims to provide evidence on the ability of BBB-ASL to measure BBB permeability and demonstrate its utility in AD-related pathologies. The presented sequence may provide novel and unique insights into the staging of BBB permeability changes in groups at greater risk of developing AD, which may, in turn, provide new targets for treatment.

Abstract Arterial spin labeling (ASL) is a non-invasive MRI technique that allows for quantitative measurement of cerebral perfusion. Incomplete or inaccurate reporting of acquisition parameters complicates quantification, analysis, and sharing of ASL data, particularly for studies across multiple sites, platforms, and ASL methods. There is a strong need for standardization of ASL data storage, including acquisition metadata. Recently, ASL-BIDS, the BIDS extension for ASL, was developed and released in BIDS 1.5.0. This manuscript provides an overview of the development and design choices of this first ASL-BIDS extension, which is mainly aimed at clinical ASL applications. Discussed are the structure of the ASL data, focussing on storage order of the ASL time series and implementation of calibration approaches, unit scaling, ASL-related BIDS fields, and storage of the labeling plane information. Additionally, an overview of ASL-BIDS compatible conversion and ASL analysis software and ASL example datasets in BIDS format is provided. We anticipate that large-scale adoption of ASL-BIDS will improve the reproducibility of ASL research.

The blood-brain barrier (BBB) consists of specialized cells that tightly regulate the in- and outflow of molecules from the blood to brain parenchyma, protecting the brain’s microenvironment. If one of the BBB components starts to fail, its dysfunction can lead to a cascade of neuroinflammatory events leading to neuronal dysfunction and degeneration. Preliminary imaging findings suggest that BBB dysfunction could serve as an early diagnostic and prognostic biomarker for a number of neurological diseases. This review aims to provide clinicians with an overview of the emerging field of BBB imaging in humans by answering three key questions: (1. Disease) In which diseases could BBB imaging be useful? (2. Device) What are currently available imaging methods for evaluating BBB integrity? And (3. Distribution) what is the potential of BBB imaging in different environments, particularly in resource limited settings? We conclude that further advances are needed, such as the validation, standardization and implementation of readily available, low-cost and non-contrast BBB imaging techniques, for BBB imaging to be a useful clinical biomarker in both resource-limited and well-resourced settings.

Abstract The aim of our work was to develop a low-cost, portable device for the fast and easy determination of total protein content by using PDMS-based lab-in-a-syringe technology with removal of 3D-printed channels. We proposed two designs with a one-step PDMS curing and a two-step PDMS-curing fabrication procedure. The one-step PDMS microdevices were found to be the best in the view of preparation, repeatability, and stability of the reagent. This design was then applied for the determination of total protein content in biomedical products using the Bradford assay.

Arterial spin labeling (ASL) is a non-invasive and cost-effective MRI technique for brain perfusion measurements. While it has developed into a robust technique for scientific and clinical use, its image processing can still be daunting. The 2019 Ann Arbor ISMRM ASL working group established that education is one of the main areas that can accelerate the use of ASL in research and clinical practice. Specifically, the post-acquisition processing of ASL images and their preparation for region-of-interest or voxel-wise statistical analyses is a topic that has not yet received much educational attention. This educational review is aimed at those with an interest in ASL image processing and analysis. We provide summaries of all typical ASL processing steps on both single-subject and group levels. The readers are assumed to have a basic understanding of cerebral perfusion (patho) physiology; a basic level of programming or image analysis is not required. Starting with an introduction of the physiology and MRI technique behind ASL, and how they interact with the image processing, we present an overview of processing pipelines and explain the specific ASL processing steps. Example video and image illustrations of ASL studies of different cases, as well as model calculations, help the reader develop an understanding of which processing steps to check for their own analyses. Some of the educational content can be extrapolated to the processing of other MRI data. We anticipate that this educational review will help accelerate the application of ASL MRI for clinical brain research.

Abstract Drug-resistant epilepsy is a diagnostic and therapeutic challenge, mainly in patients with negative MRI findings. State-of-the-art imaging methods complement standard epilepsy protocols with new information and help epileptologists to increase the reliability of their decisions. In this study, we investigate whether arterial spin labeling (ASL) perfusion MRI can help localize the epileptogenic zone (EZ). To that end, we developed an image processing method to detect the EZ as an area with hypoperfusion relative to the contralateral unaffected side, using subject-specific thresholding of the asymmetry index in ASL images. We demonstrated three thresholding criteria (termed minimal product criterion, minimal distance criterion, and elbow criterion) on 29 patients with MRI-negative epilepsy (age 32.98 ± 10.4 years). The minimal product criterion showed optimal results in terms of positive predictive value (mean 0.12 in postoperative group and 0.22 in preoperative group) and true positive rate (mean 0.71 in postoperative group and 1.82 in preoperative group). Additionally, we found high accuracy in determining the EZ side (mean 0.86 in postoperative group and 0.73 in preoperative group out of 1.00). ASL can be easily incorporated into the standard presurgical MR protocol, and it provides an additional benefit in EZ localization.

Background: Arterial spin labeling (ASL) magnetic resonance imaging (MRI) may be a promising technique to evaluate the presence of cerebral atherosclerosis. We tested whether the new and easily calculated ASL MRI parameter for vascular and tissue signal distribution - ‘spatial coefficient of variation’ (ASL-sCoV) - is a better radiological marker for atherosclerotic risk than the more conventional markers of white matter hyperintensity (WMH) volume and cerebral blood flow (ASL-CBF). Methods: Participants of the preDIVA trial (n = 195), aged 72–80 years with systolic hypertension (>140 mmHg) underwent two MRI scans two to three years apart. WMH volume was derived from 3D FLAIR-MRI; gray matter ASL-CBF and ASL-sCoV from ASL-MRI. Atherosclerotic risk was operationalized as 10-year cardiovascular risk by the Systematic COronary Risk Evaluation Older Persons (SCORE O.P) and calculated at baseline and follow-up. Data were analyzed using linear regression. Results: ASL-CBF was associated with atherosclerotic risk scores at baseline (standardized-beta = -0.26, 95 %CI = -0.40 to −0.13, p

The European Prevention of Alzheimer Dementia (EPAD) is a multi-center study that aims to characterize the preclinical and prodromal stages of Alzheimer’s Disease. The EPAD imaging dataset includes core (3D T1w, 3D FLAIR) and advanced (ASL, diffusion MRI, and resting-state fMRI) MRI sequences.Here, we give an overview of the semi-automatic multimodal and multisite pipeline that we developed to curate, preprocess, quality control (QC), and compute image-derived phenotypes (IDPs) from the EPAD MRI dataset. This pipeline harmonizes DICOM data structure across sites and performs standardized MRI preprocessing steps. A semi-automated MRI QC procedure was implemented to visualize and flag MRI images next to site-specific distributions of QC features — i.e. metrics that represent image quality. The value of each of these QC features was evaluated through comparison with visual assessment and step-wise parameter selection based on logistic regression. IDPs were computed from 5 different MRI modalities and their sanity and potential clinical relevance were ascertained by assessing their relationship with biological markers of aging and dementia.The EPAD v1500.0 data release encompassed core structural scans from 1356 participants 842 fMRI, 831 dMRI, and 858 ASL scans. From 1356 3D T1w images, we identified 17 images with poor quality and 61 with moderate quality. Five QC features — Signal to Noise Ratio (SNR), Contrast to Noise Ratio (CNR), Coefficient of Joint Variation (CJV), Foreground-Background energy Ratio (FBER), and Image Quality Rate (IQR) — were selected as the most informative on image quality by comparison with visual assessment. The multimodal IDPs showed greater impairment in associations with age and dementia biomarkers, demonstrating the potential of the dataset for future clinical analyses.

Capillary electrophoresis connected with tandem mass spectrometry was employed for the development of a method for determination of various tyrosine kinase inhibitors in plasma samples. A stacking online preconcentration with a 120 cm-long capillary was used for the determination of bosutinib, dasatinib, canertinib, and erlotinib at physiologically relevant concentrations. The optimization included both capillary electrophoresis and mass spectrometry steps. Under optimal conditions, 50 mM formic acid pH 2.5, an injection time of 120 s, and an optimized mass spectrometry set-up (as sheath liquid composition 75:24.9:0.1 (v/v) methanol, water, formic acid, and appropriate conditions for ion transitions), LODs in a range of 3.9–23.0 nmol·L−1 were observed. The method was validated in terms of linearity, limit of detection, limit of quantification, repeatability of migration times and peak area, and recovery using plasma as a matrix for analytes. The results showed that this method has great promise for use in many analytical tasks, e.g., therapeutic drug monitoring.

Metal–organic frameworks (MOFs), as high-surface-area materials, have shown promise in various areas of application, such as chiral sensing and separation, due to their flexibility in design and organized porous cages. Researchers have been striving to design and develop high-performance enantiorecognition and separation analytical techniques in chiral science fields. The main aim of this review is to provide a comprehensive overview of chirality, state-of-the-art MOFs in chirality, and chiral analysis in the past decade, 2012–2022. The classification of this review includes chirality, principles of chiral analysis, the attraction of functional materials in chirality, MOFs in chiral analysis, MOFs for designing enantioselective sensors (fluorescence, circular dichroism, quartz crystal microbalance, electrochemical), and MOFs as chiral stationary phases (CSPs) for chromatographic enantioseparation (high-performance liquid chromatography, gas chromatography, and capillary electrochromatography). Finally, this review covers the vital progress of these materials with attention to the available opportunities and challenges in this topic.

Spatial normalization is an important step for group image processing and evaluation of mean brain perfusion in anatomical regions using arterial spin labeling (ASL) MRI and is typically performed via high-resolution structural brain scans. However, structural segmentation and/or spatial normalization to standard space is complicated when gray-white matter contrast in structural images is low due to ongoing myelination in newborns and infants. This problem is of particularly clinical relevance for imaging infants with inborn or acquired disorders that impair normal brain development. We investigated whether the ASL MRI perfusion contrast is a viable alternative for spatial normalization, using a pseudo-continuous ASL acquired using a 1.5 T MRI unit (GE Healthcare). Four approaches have been compared: (1) using the structural image contrast, or perfusion contrast with (2) rigid, (3) affine, and (4) nonlinear transformations – in 16 healthy controls [median age 0.83 years, inter-quartile range (IQR) ± 0.56] and 36 trigonocephaly patients (median age 0.50 years, IQR ± 0.30) – a non-syndromic type of craniosynostosis. Performance was compared quantitatively using the real-valued Tanimoto coefficient (TC), visually by three blinded readers, and eventually by the impact on regional cerebral blood flow (CBF) values. For both patients and controls, nonlinear registration using perfusion contrast showed the highest TC, at 17.51 (CI 6.66–49.38) times more likely to have a higher rating and 17.45–18.88 ml/100 g/min higher CBF compared with the standard normalization. Using perfusion-based contrast improved spatial normalization compared with the use of structural images, significantly affected the regional CBF, and may open up new possibilities for future large pediatric ASL brain studies.

Předkládaná teoretická studie se zaměřuje na otázky související s propojením formativního hodnocení a badatelsky orientované výuky ve školní praxi a k této problematice přistupuje společně pro matematiku a přírodovědné předměty (konkrétně přírodopis). Na základě společných rysů badatelsky orientované výuky v obou předmětech a s využitím teoretického modelu pro popis interakcí při poskytování okamžité zpětné vazby učitelem jsme vytvořili nový teoretický model pro popis interakcí při formativním hodnocení realizovaném během badatelsky orientované výuky. Výsledný teoretický model pro formativní hodnocení při badatelsky orientované výuce představujeme prostřednictvím sady schémat, která obecně popisují průběh výukového bloku s badatelskou úlohou z pohledu formativního hodnocení, a prostřednictvím nového tzv. double:ESRU modelu pro kódování různých typů interakcí, ke kterým dochází při formativním hodnocení. Možnosti teoretického modelu ilustrují podrobné analýzy dvou virtuálních výukových bloků s badatelskou úlohou (matematického a přírodopisného). Prezentovaný model nabízí pedagogickému výzkumu nástroj pro podrobnou přiléhavou analýzu formativního hodnocení při badatelsky orientované výuce, učitelům a budoucím učitelům nabízí nástroj pro podporu implementace formativního hodnocení a badatelského přístupu do jejich vlastní výuky. Vizualizace propojení obou přístupů a nezávislost modelu na školním předmětu by měly pomoci porozumět možnostem, které formativní hodnocení při badatelsky orientované výuce nabízí.

Arterial spin labeling (ASL) has undergone significant development since its inception, with a focus on improving standardization and reproducibility of its acquisition and quantification. In a community-wide effort towards robust and reproducible clinical ASL image processing, we developed the software package ExploreASL, allowing standardized analyses across centers and scanners.The procedures used in ExploreASL capitalize on published image processing advancements and address the challenges of multi-center datasets with scanner-specific processing and artifact reduction to limit patient exclusion. ExploreASL is self-contained, written in MATLAB and based on Statistical Parameter Mapping (SPM) and runs on multiple operating systems. To facilitate collaboration and data-exchange, the toolbox follows several standards and recommendations for data structure, provenance, and best analysis practice.ExploreASL was iteratively refined and tested in the analysis of >10,000 ASL scans using different pulse-sequences in a variety of clinical populations, resulting in four processing modules: Import, Structural, ASL, and Population that perform tasks, respectively, for data curation, structural and ASL image processing and quality control, and finally preparing the results for statistical analyses on both single-subject and group level. We illustrate ExploreASL processing results from three cohorts: perinatally HIV-infected children, healthy adults, and elderly at risk for neurodegenerative disease. We show the reproducibility for each cohort when processed at different centers with different operating systems and MATLAB versions, and its effects on the quantification of gray matter cerebral blood flow.ExploreASL facilitates the standardization of image processing and quality control, allowing the pooling of cohorts which may increase statistical power and discover between-group perfusion differences. Ultimately, this workflow may advance ASL for wider adoption in clinical studies, trials, and practice.

To summarize the distribution of glioma location within a patient population, registration of individual MR images to anatomical reference space is required. In this study, we quantified the accuracy of MR image registration to anatomical reference space with linear and non-linear transformations using estimated tumor targets of glioblastoma and lower-grade glioma, and anatomical landmarks at pre- and post-operative time-points using six commonly used registration packages (FSL, SPM5, DARTEL, ANTs, Elastix, and NiftyReg). Routine clinical pre- and post-operative, post-contrast T1-weighted images of 20 patients with glioblastoma and 20 with lower-grade glioma were collected. The 2009a Montreal Neurological Institute brain template was used as anatomical reference space. Tumors were manually segmented in the patient space and corresponding healthy tissue was delineated as a target volume in the anatomical reference space. Accuracy of the tumor alignment was quantified using the Dice score and the Hausdorff distance. To measure the accuracy of general brain alignment, anatomical landmarks were placed in patient and in anatomical reference space, and the landmark distance after registration was quantified. Lower-grade gliomas were registered more accurately than glioblastoma. Registration accuracy for pre- and post-operative MR images did not differ. SPM5 and DARTEL registered tumors most accurate, and FSL least accurate. Non-linear transformations resulted in more accurate general brain alignment than linear transformations, but tumor alignment was similar between linear and non-linear transformation. We conclude that linear transformation suffices to summarize glioma locations in anatomical reference space.

Přehledová studie zpracovává aktuální domácí a zahraniční přístupy k využívání videa v učitelském vzdělávání. Poukazuje na kontinuitu vývoje, kdy se videozáznamy původně pořizované pro výzkumné účely v přibývající míře používají v přípravném a dalším vzdělávání učitelů. Přehledová studie je rozvržena do čtyř částí. V první části je pojednán kontext učitelského vzdělávání, v němž se videa používají, a je zde představeno devět vybraných přístupů, které jsou v odborné literatuře zdokumentovány. Ve druhé části jsou zodpovídány čtyři otázky, které si přehledová studie klade: (1) Jak je daný přístup začleněn do rámcové koncepce učitelského vzdělávání / podpory profesního rozvoje? (2) Jaké cíle/účely stojí v základu daného přístupu? (3) Jaké komponenty jsou součástí celku a jakou plní funkci? (4) Jaké konkrétní aktivity (uživatelů, popř. tutorů či tvůrců) jsou s videem v rámci přístupu realizovány a co se jimi má rozvíjet? Ve třetí části přehledové studie jsou diskutovány výzvy, které se v dané oblasti objevují, jakkoliv ještě mnohdy nejsou reflektovány v související odborné literatuře. Jedná se o možnosti využití virtuální reality a 360o videí a o možnostech simulované a inscenované výuky jako alternativě videozáznamů – to vše v etických souvislostech využívání videa v učitelském vzdělávání. Čtvrtá část přehledové studie je výhledem, který se pokouší odpovědět na otázku, zda lze formulovat určitá měkká doporučení (guidelines), která by mohla vést vývoj v této oblasti.Přehledová studie zpracovává aktuální domácí a zahraniční přístupy k využívání videa v učitelském vzdělávání. Poukazuje na kontinuitu vývoje, kdy se videozáznamy původně pořizované pro výzkumné účely v přibývající míře používají v přípravném a dalším vzdělávání učitelů. Přehledová studie je rozvržena do čtyřčástí. V prvníčásti je pojednánkontext učitelského vzdělávání, v němžse videa používají, a je zde představeno devět vybranýchpřístupů, kteréjsou v odbornéliteratuře zdokumentovány. Ve druhéčásti jsou zodpovídányčtyři otázky, kterési přehledovástudie klade: (1) Jak je danýpřístup začleněn do rámcovékoncepce učitelského vzdělávání / podpory profesního rozvoje? (2) Jaké cíle/účely stojí v základu daného přístupu? (3) Jaké komponenty jsou součástí celku a jakou plní funkci? (4) Jaké konkrétní aktivity (uživatelů, popř. tutorů či tvůrců) jsou s videem v rámci přístupu realizovány a co se jimi má rozvíjet? Vetřetíčásti přehledovéstudie jsou diskutovány výzvy, kterése v danéoblasti objevují, jakkoliv ještěmnohdy nejsou reflektovány v souvisejícíodbornéliteratuře. Jednáse o možnosti využitívirtuálníreality a 360o videí a o možnostech simulované a inscenované výuky jako alternativě videozáznamů – to vše v etických souvislostech využívání videa v učitelském vzdělávání. Čtvrtá část přehledové studie je výhledem, který se pokouší odpovědět na otázku, zda lze formulovat určitá měkká doporučení (guidelines), která by mohla vést vývoj v této oblasti.

Clinical interpretation of arterial spin labeling (ASL) perfusion MRI in cerebrovascular disease remains challenging mainly because of the method's sensitivity to concomitant contributions from both intravascular and tissue compartments. While acquisition of multi-delay images can differentiate between the two contributions, the prolonged acquisition is prone to artifacts and not practical for clinical applications. Here, the utility of the spatial coefficient of variation (sCoV) of a single-delay ASL image as a marker of the intravascular contribution was evaluated by testing the hypothesis that sCoV can detect the effects of differences in label arrival times between ipsi- and contra-lateral hemispheres even in the absence of a hemispheric difference in CBF. Hemispheric lateralization values for sCoV and CBF were computed from ASL images acquired on 28 patients (age 73.9 ± 10.2 years, 8 women) with asymptomatic unilateral carotid occlusion. The results showed that sCoV lateralization predicted the occluded side with 96.4% sensitivity, missing only 1 patient. In contrast, the sensitivity of the CBF lateralization was 71.4%, with 8 patients showing no difference in CBF between hemispheres. The findings demonstrate the potential clinical utility of sCoV as a cerebrovascular correlate of large vessel disease. Using sCoV in tandem with CBF, vascular information can be obtained in image processing without the need for additional scan-time.

In our work, we produced PDMS-based microfluidic devices by mechanical removal of 3D-printed scaffolds inserted in PDMS. Two setups leading to the fabrication of monolithic PDMS-based microdevices and bonded (or stamped) PDMS-based microdevices were designed. In the monolithic devices, the 3D-printed scaffolds were fully inserted in the PDMS and then carefully removed. The bonded devices were produced by forming imprints of the 3D-printed scaffolds in PDMS, followed by bonding the PDMS parts to glass slides. All these microfluidic devices were then successfully employed in three proof-of-concept applications: capture of magnetic microparticles, formation of droplets, and isotachophoresis separation of model organic dyes.

The capability to present electronic media that can preserve information is highly restricted to few decades (e.g., a lifetime of DVD media does not exceed 100 years), and therefore the question of how to preserve documents for more than thousands or millions of years presents a challenging task. In this article, we discuss three thinkable possibilities for long-term data storage: (i) self-assembly systems, (ii) chirality, and (iii) nucleic acids. These systems have, in our opinion, added-value regarding functionality and storing capability. Self-assembly systems form 3D structures, which could reflect any information more precisely than a 2D structure, and therefore they could be used as a training information package. Chirality provides the next added value in the possibility of using an interval of for storing the data (fuzzy logic) and could be also interesting in increasing the storage capacity if using compounds with more chiral centers, such as polysaccharides. Finally, nucleic acids represent a method of storage in which the reading step is developed and probably will be still active if people inhabit the Earth, which will realize the whole process of writing/storing and reading easier.

Water erosion poses a significant threat to more than 50% of agricultural land in the Czech Republic. Maize (Zea mays L.) is particularly susceptible to soil erosion, with the bare soil space between maize rows exposed to erosive agents. Intercropping has emerged as a potential solution to mitigate soil erosion risks in maize cultivation. A series of soil erosion field experiments were conducted from 2022 to 2023 using natural rainfall to investigate the influence of selected intercrop mixtures during the growing season on sediment yields and surface runoff volume. The results revealed a gradual decrease in surface runoff volume and sediment yields over the growing season. Significantly reduced surface runoff volume and soil loss were observed in two tested intercropped plots S2 - rye (Secale cereale) and incarnate clover (Trifolium incarnatum); S3 - ryegrass only (Lolium)), compared to a control plot managed conventionally with maize (S1). Surface runoff volume and soil loss from S2 and S3 reached 2.57-43.5% and 1.26-11.65% of the control plot, respectively. These findings highlight the soil conservation effect of intercrop technologies (S2 and S3) in mitigating soil erosion in maize cultivation. The importance of vegetation cover in reducing soil erosion intensified over time. Intercropping holds promise as a sustainable agricultural management strategy for sloping maize fields.

Abstract Consensus holds that pottery technology came to Central Europe from the Northern Balkans with independent pottery traditions existing concurrently in Eastern Europe. An unusual grass-tempered pottery dating back to around 5800 cal BC found in lake sediments at Santovka, Slovakia, predated the earliest known Neolithic pottery in the region (~ 5500 cal BC), suggesting unexplored narratives of pottery introduction. Analyses of the pottery’s technology, origin, and grass temper shedding light on ceramic traditions' spread can unveil mobility patterns and community lifestyles. Our findings indicate a non-local provenance, low temperature firing, Festuca sp. grass temper and unique rectangular or cylindrical vessel shapes which align with Eastern European hunter-gatherer practices. Moreover, the pottery style and technology have no analogies in the contemporary Danubian pottery traditions and have more similarities to those of the Eastern traditions. The pottery's raw materials likely originated from distant areas, indicating extensive territorial access for its creators. Our findings imply late Mesolithic hunter-gatherers as the probable artisans and with implications for the site's significance in the late Mesolithic landscape.

The interaction between music and the environment has been widely investigated in various domains; however, the effects of music on the perception of outdoor environments have not been adequately examined. A better understanding of audio-visual interactions between music and the natural environment is important for music psychology, because the field is currently employing natural sounds, yet their pairing remains poorly understood. Furthermore, this understanding is vital for soundscape research, given that individuals are increasingly listening to music on headphones in natural settings. This has practical implications wherever music and the natural environment are paired. This study explored the audio-visual interaction between music and the perception of natural environments. Four types of natural images were presented based on their attractiveness/unattractiveness and visual openness/closedness. At the same time, the participants listened to sad or happy music. Both self-reported assessment data and data obtained through automated software analysis of emotional facial expressions represented in the form of emotional engagement were analyzed. The results showed that, compared to listening to sad music or no music, exposure to happy music resulted in an increase in self-reported environmental preference. However, sad music did not significantly decrease self-reported environmental preference or self-reported pleasant feelings compared to the control no-music condition. Analysis of the engagement in facial emotional expressions showed that sad music decreased engagement compared to the no-music condition in all types of environments; however, when listening to happy music, the participants’ engagement was lower in unattractive environments but not in attractive environments compared to when they did not listen to any music.