Een archeologische evaluatie en waardering van houtskoolmeilers in het Zoerselbos (Zoersel, provincie Antwerpen)

Dit waarderend onderzoek van de restanten van houtskoolmeilers in het Zoerselbos biedt een historische en archeologische onderbouwing voor het behoud van dit bijzondere erfgoed. Naast het Grotenhout (Gierle) en het s Herenbos (Malle) is het Zoerselbos één van de weinige oudboskernen in het Kempisch district. Het behoort tot de meest waardevolle en belangrijke bosgebieden in Vlaanderen. Het gebied is beschermd als landschap en maakt deel uit van een ankerplaats. Bovenop vroeger onderzoek naar o.a. de ecohydrologie en biotoopkarteringen, die naast bijzondere ecologische elementen ook al cultuurhistorische elementen opnamen zoals houtskoolmeilers, ijskelders, mottes, laagovens, biedt dit interdisciplinaire onderzoeksproject op basis van archiefmateriaal, natuurhistorische waarden en landschappelijke relicten een beter beeld van dit oude bos als historisch (gebruikt) landschap. Concreet levert het archeologisch en paleo-ecologisch terreinonderzoek inzicht in het aantal, de ligging, het type, de opbouw en de bijhorende structuren, de omvang, de gebruikte houtsoorten, de ouderdom, de diachronische ontwikkeling, de seizoenaliteit en het hergebruik van de historische houtskoolmeilers in Zoerselbos. Restanten van houtskoolmeilers vormen historisch erfgoed dat buiten de oude bosgebieden door grondbewerking volledig verdwenen is. Het onderzoek in Zoerselbos toonde ook aan hoe weinig er van deze houtskoolmeilers gekend is. Het rapport besluit met een concreet beschermingsvoorstel en met aanbevelingen voor verder onderzoek en beheer van deze relicten

The polymeric glyco-linker controls the signal outputs for plasmonic gold nanorod biosensors due to biocorona formation

Gold nanorods (GNRs) are a promising platform for nanoplasmonic biosensing. The localised surface plasmon resonance (LSPR) peak of GNRs is located in the near-infrared optical window and is sensitive to local binding events, enabling label-free detection of biomarkers in complex biological fluids. A key challenge in the development of such sensors is achieving target affinity and selectivity, while both minimizing non-specific binding and maintaining colloidal stability. Herein, we reveal how GNRs decorated with galactosamine-terminated polymer ligands display significantly different binding responses in buffer compared to serum, due to biocorona formation, and how biocorona displacement due to lectin binding plays a key role in their optical responses. GNRs were coated with either poly(N-(2-hydroxypropyl)methacrylamide) (PHPMA) or poly(N-hydroxyethyl acrylamide) (PHEA) prepared via reversible addition–fragmentation chain-transfer (RAFT) polymerisation and end-functionalised with galactosamine (Gal) as the lectin-targeting unit. In buffer Gal-PHEA-coated GNRs aggregated upon soybean agglutinin (SBA) addition, whereas Gal-PHPMA-coated GNRs exhibited a red-shift of the LSPR spectrum without aggregation. In contrast, when incubated in serum Gal-PHPMA-coated nanorods showed no binding response, while Gal-PHEA GNRs exhibited a dose-dependent blue-shift of the LSPR peak, which is the opposite direction (red-shift) to what was observed in buffer. This differential behaviour was attributed to biocorona formation onto both polymer-coated GNRs, shown by differential centrifugal sedimentation and nanoparticle tracking analysis. Upon addition of SBA to the Gal-PHEA coated nanorods, signal was generated due to displacement of weakly-bound biocorona components by lectin binding. However, in the case of Gal-PHPMA which had a thicker corona, attributed to lower polymer grafting densities, addition of SBA did not lead to biocorona displacement and there was no signal output. These results show that plasmonic optical responses in complex biological media can be significantly affected by biocorona formation, and that biocorona formation itself does not prevent sensing so long as its exact nature (e.g. ‘hard versus soft’) is tuned

Plausibility and redundancy analysis to select FDG-PET textural features in non-small cell lung cancer

Contains fulltext : 232784.pdf (Publisher’s version ) (Open Access)BACKGROUND: Radiomics refers to the extraction of a large number of image biomarker describing the tumor phenotype displayed in a medical image. Extracted from positron emission tomography (PET) images, radiomics showed diagnostic and prognostic value for several cancer types. However, a large number of radiomic features are nonreproducible or highly correlated with conventional PET metrics. Moreover, radiomic features used in the clinic should yield relevant information about tumor texture. In this study, we propose a framework to identify technical and clinical meaningful features and exemplify our results using a PET non-small cell lung cancer (NSCLC) dataset. MATERIALS AND METHODS: The proposed selection procedure consists of several steps. A priori, we only include features that were found to be reproducible in a multicenter setting. Next, we apply a voxel randomization step to identify features that reflect actual textural information, that is, that yield in 90% of the patient scans a value significantly different from random texture. Finally, the remaining features were correlated with standard PET metrics to further remove redundancy with common PET metrics. The selection procedure was performed for different volume ranges, that is, excluding lesions with smaller volumes in order to assess the effect of tumor size on the results. To exemplify our procedure, the selected features were used to predict 1-yr survival in a dataset of 150 NSCLC patients. A predictive model was built using volume as predictive factor for smaller, and one of the selected features as predictive factor for bigger lesions. The prediction accuracy of the both models were compared with the prediction accuracy of volume. RESULTS: The number of selected features depended on the lesion size included in the analysis. When including the whole dataset, from 19 features reflecting actual texture only two were found to be not strongly correlated with conventional PET metrics. When excluding lesions smaller than 11.49 and 33.10 mL (25 and 50 percentile of the dataset), four out of 27 features and 13 out of 29 features remained after eliminating features highly correlated with standard PET metrics. When excluding lesions smaller than 103.9 mL (75 percentile), 33 out of 53 features remained. For larger lesions, some of these features outperformed volume in terms of classification accuracy (increase of 4-10%). The combination of using volume as predictor for smaller and one of the selected features for larger lesions also improved the accuracy when compared with volume only (increase from 72% to 76%). CONCLUSION: When performing radiomic analysis for smaller lesions, it should be first carefully investigated if a textural feature reflects actual heterogeneity information. Next, verification of the absence of correlation with all conventional PET metrics is essential in order to assess the additional value of radiomic features. Radiomic analysis with lesions larger than 11.4 mL might give additional information to conventional metrics while at the same time reflecting actual tumor texture. Using a combination of volume and one of the selected features for prediction yields promise to increase accuracy and reliability of a radiomic model

Convenient synthesis and polymerization of 5,6-disubstituted dithiophthalides toward soluble poly(isothianaphthene):An initial spectroscopic characterization of the resulting low-band-gap polymers

A new synthetic procedure toward substituted dithiophthalides, 5,6-dialkyloxydithiophthalide and 5,6-dithioalkyldithiophthalide, is presented. 5,6-Dithiooctyldithiophthalide was obtained from 4,5-dichlorophthalic acid in an eight-step reaction with an overall yield of 26%. 5,6-Dioctyloxydithiophthalide was obtained from 4,5-dihydroxyphthalic acid dimethyl ester in a seven-step reaction (overall yield 15%). Both monomers were polymerized by a thermal and nonoxidative polymerization that resulted in soluble poly(isothianaphthene) derivatives with a band gap of about 1.2 eV. Photoinduced absorption measurements revealed the existence of charged excitations upon illumination. The photoinduced charge generation, combined with the extensive light-harvesting properties and the easy processability, makes these materials quite promising for photovoltaic applications. (C) 2003 Wiley Periodicals, Inc