93 research outputs found
THE MIDDLE MINOAN III BUILDING COMPLEX AT ALONAKI, JUKTAS. ARCHITECTURAL OBSERVATIONS AND POTTERY ANALYSIS
The building complex at Alonaki is investigated here, and patterns of pottery production and consumption in particular, due to the belief that an overview of the pottery and architecture sheds light on the role that Alonaki played in the Middle Minoan III period. The site should be viewed in connection with the Anemospelia building and the peak sanctuary with which it forms a unique triad. The evidence of the pottery shows that the bulk of the assemblage should be placed chronologically in the mature MM IIIA period. A unit is also devoted to the ‘great South Road from Knossos’, as Evans calls it, a branch of which meets the Minoan road from Junktas
Πολυκριτηριακός Προσδιορισμός Θερμικού Κινδύνου σε Αστικές Περιοχές – Εφαρμογή στον Δήμο Αθηναίων
Η ανομοιογενής μορφολογία των πόλεων, με τα έντονα χωρικά εναλλασσόμενα πολεοδομικά χαρακτηριστικά, έχει ως αποτέλεσμα την ύπαρξη διαφορετικών μικροκλιμάτων, που το καθένα εξαρτάται από παράγοντες που χαρακτηρίζουν τη συγκεκριμένη περιοχή. Το πρόβλημα της αστικής θερμικής νησίδας εμφανίζεται όλο και εντονότερα στις σύγχρονες πόλεις εξαιτίας της αυξανόμενης αστικοποίησης σε συνδυασμό με την κλιματική αλλαγή. Πλέον, επιβάλλεται η εκτίμηση των επιπτώσεών του σε κλίμακα γειτονιάς και όχι με την παραδοσιακή προσέγγιση ολόκληρης της πόλης. Αυτό επιτρέπει τον εντοπισμό των περιοχών εκείνων, τα χαρακτηριστικά των οποίων εκθέτουν τους κατοίκους σε κίνδυνο, όταν οι θερμοκρασίες είναι αυξημένες. Βάσει των παραπάνω, η χωρική αποτύπωση του θερμικού κινδύνου μιας περιοχής είναι απαραίτητο στοιχείο στη διαχείριση των σύγχρονων πόλεων.
Στην παρούσα εργασία, ακολουθήθηκε για πρώτη φορά μεθοδολογία βασισμένη σε δορυφορικά δεδομένα για τον προσδιορισμό του θερμικού κινδύνου του Δήμου Αθηναίων, που αποτελεί την περιοχή μελέτης, σε υψηλή χωρική ανάλυση. Η μελέτη πραγματοποιήθηκε για μία τυπική καλοκαιρινή ημέρα (22/07/2020) με τη χρήση δορυφορικών δεδομένων από διάφορες πηγές και στατιστικών κοινωνικοοικονομικών δεδομένων από την επίσημη Απογραφή του 2011. Για την επεξεργασία των δεδομένων χρησιμοποιήθηκε το λογισμικό QGIS, που είναι ένα σύστημα γεωγραφικών πληροφοριών ανοιχτού κώδικα.
Για τον προσδιορισμό του θερμικού κινδύνου ήταν απαραίτητη η εκτίμηση της έκθεσης και της ευαισθησίας των κατοίκων των διάφορων περιοχών του Δήμου Αθηναίων ως προς τις υψηλές θερμοκρασίες. Ο υπολογισμός της έκθεσης βασίστηκε στην κατηγοριοποίηση του Δήμου Αθηναίων σε περιοχές με κοινά αστικά μορφολογικά – πολεοδομικά χαρακτηριστικά καθώς και ομοιογένεια ως προς την επιφανειακή θερμοκρασία εδάφους και την παρουσία βλάστησης. Αυτό επιτεύχθηκε με τη χρήση ενός καινοτόμου αλγορίθμου μη επιβλεπόμενης συσταδοποίησης σε προγραμματιστικό περιβάλλον R. Ο υπολογισμός της ευαισθησίας βασίστηκε σε στατιστικά κοινωνικοοικονομικά δεδομένα που χαρακτηρίζουν τις επτά (7) Δημοτικές Κοινότητες του Δήμου Αθηναίων, καθώς αυτή ήταν η καλύτερη χωρική ανάλυση που υπήρχε διαθέσιμη.
Τα αποτελέσματα ανέδειξαν τις περιοχές εκείνες του Δήμου Αθηναίων όπου ο θερμικός κίνδυνος είναι αυξημένος και στις οποίες επιβάλλεται να προτεραιοποιηθούν μέτρα παρέμβασης για την αντιμετώπισή του. Παράλληλα, εντοπίστηκαν συγκεκριμένες κρίσιμες υποδομές εντός του Δήμου Αθηναίων, όπως σχολεία, αθλητικοί χώροι και δημοτικές υπηρεσίες, οι οποίες βρίσκονται σε περιοχές με αυξημένο θερμικό κίνδυνο. Η μελέτη κατέδειξε τον διαχωρισμό του Δήμου Αθηναίων σε δύο επιμέρους τμήματα, στο δυτικό και βόρειο τμήμα και στο ανατολικό, με το πρώτο να έχει αυξημένο θερμικό κίνδυνο και το δεύτερο να έχει μειωμένο θερμικό κίνδυνο.The heterogeneous morphology of cities and the spatially alternating urban features, result in the existence of different microclimates within the city each depending on factors that characterize the particular area. The problem of urban heat island appears more often and more intense in modern cities due to increasing urbanization combined with climate change. Nowadays, it is necessary to assess its impacts on a neighborhood scale and not with the traditional approach of the whole city as one unit. This allows the identification of the specific areas within the city, the characteristics of which expose residents to danger when temperatures are elevated. Based on the above, the spatial mapping of the thermal risk of an area is an essential element in the management of modern cities.
In this study, a methodology based on satellite data was followed for the first time to assess the thermal risk of the Municipality of Athens, which is the study area, in high spatial resolution. The study was carried out for a typical summer day (22/07/2020), using satellite data from various sources and statistical socio-economic data from the official Census of 2011. The data was processed using the QGIS software, which is an open-source geographic information system.
In order to determine the thermal risk, it was necessary to assess the exposure and sensitivity of the residents of the various areas of the Municipality of Athens related to high temperatures. The calculation of the exposure was based on the categorization of the Municipality of Athens in areas with common urban morphological characteristics as well as homogeneity in terms of land surface temperature and the presence of vegetation. This was achieved by using an innovative unsupervised clustering algorithm using the R programming environment. The calculation of the sensitivity was based on statistical socio-economic data that characterize the seven (7) Municipal Communities of the Municipality of Athens, as this was the highest spatial resolution available.
The results highlighted the areas of the Municipality of Athens where the thermal risk is increased and where intervention measures should be prioritized to address the issue. At the same time, specific critical infrastructure within the Municipality of Athens were identified, such as schools, sports facilities and municipality services, which are located in areas with increased thermal risk. The study showed the division of the Municipality of Athens into two sub-parts, the western and northern part and the eastern part, with the first having increased thermal risk and the second having reduced thermal risk
Identification of distinct SET/TAF-Iβ domains required for core histone binding and quantitative characterisation of the interaction
<p>Abstract</p> <p>Background</p> <p>The assembly of nucleosomes to higher-order chromatin structures is finely tuned by the relative affinities of histones for chaperones and nucleosomal binding sites. The myeloid leukaemia protein SET/TAF-Iβ belongs to the NAP1 family of histone chaperones and participates in several chromatin-based mechanisms, such as chromatin assembly, nucleosome reorganisation and transcriptional activation. To better understand the histone chaperone function of SET/TAF-Iβ, we designed several SET/TAF-Iβ truncations, examined their structural integrity by circular Dichroism and assessed qualitatively and quantitatively the histone binding properties of wild-type protein and mutant forms using GST-pull down experiments and fluorescence spectroscopy-based binding assays.</p> <p>Results</p> <p>Wild type SET/TAF-Iβ binds to histones H2B and H3 with K<sub>d </sub>values of 2.87 and 0.15 μM, respectively. The preferential binding of SET/TAF-Iβ to histone H3 is mediated by its central region and the globular part of H3. On the contrary, the acidic C-terminal tail and the amino-terminal dimerisation domain of SET/TAF-Iβ, as well as the H3 amino-terminal tail, are dispensable for this interaction.</p> <p>Conclusion</p> <p>This type of analysis allowed us to assess the relative affinities of SET/TAF-Iβ for different histones and identify the domains of the protein required for effective histone recognition. Our findings are consistent with recent structural studies of SET/TAF-Iβ and can be valuable to understand the role of SET/TAF-Iβ in chromatin function.</p
Overexpression of Prothymosin Alpha Predicts Poor Disease Outcome in Head and Neck Cancer
In our recent study, tissue proteomic analysis of oral pre-malignant lesions (OPLs) and normal oral mucosa led to the identification of a panel of biomarkers, including prothymosin alpha (PTMA), to distinguish OPLs from histologically normal oral tissues. This study aimed to determine the clinical significance of PTMA overexpression in oral squamous cell hyperplasia, dysplasia and head and neck squamous cell carcinoma (HNSCC).Immunohistochemistry of PTMA protein was performed in HNSCCs (n = 100), squamous cell hyperplasia (n = 116), dysplasia (n = 50) and histologically normal oral tissues (n = 100). Statistical analysis was carried out to determine the association of PTMA overexpression with clinicopathological parameters and disease prognosis over 7 years for HNSCC patients.<0.001). Chi-square analysis showed significant association of nuclear PTMA with advanced tumor stages (III+IV). Kaplan Meier survival analysis indicated reduced disease free survival (DFS) in HNSCC patients (p<0.001; median survival 11 months). Notably, Cox-multivariate analysis revealed nuclear PTMA as an independent predictor of poor prognosis of HNSCC patients (p<0.001, Hazard's ratio, HR = 5.2, 95% CI = 2.3–11.8) in comparison with the histological grade, T-stage, nodal status and tumor stage.Nuclear PTMA may serve as prognostic marker in HNSCC to determine the subset of patients that are likely to show recurrence of the disease
Histone acetylation-independent transcription stimulation by a histone chaperone
Histone chaperones are thought to be important for maintaining the physiological activity of histones; however, their exact roles are not fully understood. The physiological function of template activating factor (TAF)-I, one of the histone chaperones, also remains unclear; however, its biochemical properties have been well studied. By performing microarray analyses, we found that TAF-I stimulates the transcription of a sub-set of genes. The transcription of endogenous genes that was up-regulated by TAF-I was found to be additively stimulated by histone acetylation. On performing an experiment with a cell line containing a model gene integrated into the chromosome, TAF-I was found to stimulate the model gene transcription in a histone chaperone activity-dependent manner additively with histone acetylation. TAF-I bound to the core histones and remodeled the chromatin structure independent of the N-terminal histone tail and its acetylation level in vitro. These results suggest that TAF-I remodel the chromatin structure through its interaction with the core domain of the histones, including the histone fold, and this mechanism is independent of the histone acetylation status
Landscape genomics and biased FST approaches reveal single nucleotide polymorphisms under selection in goat breeds of North-East Mediterranean
<p>Abstract</p> <p>Background</p> <p>In this study we compare outlier loci detected using a <it>F<smcaps>ST </smcaps></it>based method with those identified by a recently described method based on spatial analysis (SAM). We tested a panel of single nucleotide polymorphisms (SNPs) previously genotyped in individuals of goat breeds of southern areas of the Mediterranean basin (Italy, Greece and Albania). We evaluate how the SAM method performs with SNPs, which are increasingly employed due to their high number, low cost and easy of scoring.</p> <p>Results</p> <p>The combined use of the two outlier detection approaches, never tested before using SNP polymorphisms, resulted in the identification of the same three loci involved in milk and meat quality data by using the two methods, while the <it>F<smcaps>ST </smcaps></it>based method identified 3 more loci as under selection sweep in the breeds examined.</p> <p>Conclusion</p> <p>Data appear congruent by using the two methods for <it>F<smcaps>ST </smcaps></it>values exceeding the 99% confidence limits. The methods of <it>F<smcaps>ST </smcaps></it>and SAM can independently detect signatures of selection and therefore can reduce the probability of finding false positives if employed together. The outlier loci identified in this study could indicate adaptive variation in the analysed species, characterized by a large range of climatic conditions in the rearing areas and by a history of intense trade, that implies plasticity in adapting to new environments.</p
Microsatellite diversity of the Nordic type of goats in relation to breed conservation: how relevant is pure ancestry?
In the last decades, several endangered breeds of livestock species have been re-established effectively. However, the successful revival of the Dutch and Danish Landrace goats involved crossing with exotic breeds and the ancestry of the current populations is therefore not clear. We have generated genotypes for 27 FAO-recommended microsatellites of these landraces and three phenotypically similar Nordic-type landraces and compared these breeds with central European, Mediterranean and south-west Asian goats. We found decreasing levels of genetic diversity with increasing distance from the south-west Asian domestication site with a south-east-to-north-west cline that is clearly steeper than the Mediterranean east-to-west cline. In terms of genetic diversity, the Dutch Landrace comes next to the isolated Icelandic breed, which has an extremely low diversity. The Norwegian coastal goat and the Finnish and Icelandic landraces are clearly related. It appears that by a combination of mixed origin and a population bottleneck, the Dutch and Danish Land-races are separated from the other breeds. However, the current Dutch and Danish populations with the multicoloured and long-horned appearance effectively substitute for the original breed, illustrating that for conservation of cultural heritage, the phenotype of a breed is more relevant than pure ancestry and the genetic diversity of the original breed. More in general, we propose that for conservation, the retention of genetic diversity of an original breed and of the visual phenotype by which the breed is recognized and defined needs to be considered separately
Prothymosin alpha: a ubiquitous polypeptide with potential use in cancer diagnosis and therapy
The thymus is a central lymphoid organ with crucial role in generating T cells and maintaining homeostasis of the immune system. More than 30 peptides, initially referred to as “thymic hormones,” are produced by this gland. Although the majority of them have not been proven to be thymus-speciWc, thymic peptides comprise an eVective group of regulators, mediating important immune functions. Thymosin fraction Wve (TFV) was the Wrst thymic extract shown to stimulate lymphocyte proliferation and diVerentiation. Subsequent fractionation of TFV led to the isolation and characterization of a series of immunoactive peptides/polypeptides, members of the thymosin family. Extensive research on prothymosin (proT) and thymosin 1 (T1) showed that they are of clinical signiWcance and potential medical use. They may serve as molecular markers for cancer prognosis and/or as therapeutic agents for treating immunodeWciencies, autoimmune diseases and malignancies. Although the molecular mechanisms underlying their eVect are yet not fully elucidated proT and T1 could be considered as candidates for cancer immunotherapy. In this review, we will focus in principle on the eventual clinical utility of proT, both as a tumor biomarker and in triggering anticancer immune responses. Considering the experience acquired via the use of T1 to treat cancer patients, we will also discuss potential approaches for the future introduction of proT into the clinical setting
- …