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Disentangling human brain connectivity requires an accurate description of neuronal trajectories. However, a detailed mapping of axonal orientations is challenging because axons can cross one another on a micrometer scale. Diffusion magnetic resonance imaging (dMRI) can be used to infer neuronal connectivity because it is sensitive to axonal alignment, but it has limited resolution and specificity. Scattered Light Imaging (SLI) and small-angle X-ray scattering (SAXS) reveal neuronal orientations with microscopic resolution and high specificity, respectively. Here, we combine both techniques to achieve a cross-validated framework for imaging neuronal orientations, with comparison to dMRI. We evaluate brain regions that include unidirectional and crossing fiber tracts in human and vervet monkey brains. We find that SLI, SAXS, and dMRI all agree regarding major fiber pathways. SLI and SAXS further quantitatively agree regarding fiber crossings, while dMRI overestimates the amount of crossing fibers. In SLI, we find a reduction of peak distance with increasing out-of-plane fiber angles, confirming theoretical predictions, validated against both SAXS and dMRI. The combination of scattered light and X-ray imaging can provide quantitative micrometer 3D fiber orientations with high resolution and specificity, enabling detailed investigations of complex tract architecture in the animal and human brain.

Alzheimer’s disease (AD) is a debilitating brain disorder that afflicts millions worldwide with no effective treatment. Currently, AD progression has primarily been characterized by abnormal accumulations of β-amyloid within plaques and phosphorylated tau within neurofibrillary tangles, giving rise to neurodegeneration due to synaptic and neuronal loss. While β-amyloid and tau deposition are required for clinical diagnosis of AD, presence of such abnormalities does not tell the complete story, and the actual mechanisms behind neurodegeneration in AD progression are still not well understood. Support for abnormal iron accumulation playing a role in AD pathogenesis includes its presence in the early stages of the disease, its interactions with β-amyloid and tau, and the important role it plays in AD related inflammation. In this review, we present the existing evidence of pathological iron accumulation in the human AD brain, as well as discuss the imaging tools and peripheral measures available to characterize iron accumulation and dysregulation in AD, which may help in developing iron-based biomarkers or therapeutic targets for the disease.

Background and ObjectivesRepeated concussive and sub-concussive impacts in high-contact sports can affect the brain’s microstructure, which can be studied using diffusion MRI. Most prior imaging studies, however, employ a cross-sectional design, do not include low-contact players as controls, or use traditional diffusion tensor imaging without investigating novel tractspecific microstructural metrics.MethodsWe examined brain microstructure in 63 high-contact (American football) and 34 low-contact (volleyball) collegiate athletes with up to 4 years of follow-up (315 total scans) using advanced diffusion MRI, a comprehensive set of multi-compartment models, and automated fiber quantification tools. We investigated diffusion metrics along the length of tracts using nested linear mixed-effects models to ascertain the acute and chronic effects of sub-concussive and concussive impacts, as well as associations between diffusion changes with clinical, behavioral, and sports-related measures.ResultsSignificant longitudinal increases in fractional anisotropy and axonal water fraction were detected in volleyball players, but not in football players, along with decreases in radial and mean diffusivity as well as orientation dispersion index (all findings absolute T-statistic > 3.5, p < .0001). This pattern was present in the callosum forceps minor, left superior longitudinal fasciculus, left thalamic radiation, and right cingulum hippocampus. Longitudinal group differences were more prominent and observed in a larger number of tracts in concussed (previously or in-study) football players (p < .0001), while smaller effects were noted in un-concussed players. An analysis of immediate-post concussion scans in football players demonstrated a transient localized increase in axial diffusivity, mean and radial kurtosis in the left uncinate and right cingulum hippocampus (p < .0001). Finally, football players with high position-based sub-concussive risk demonstrated increased orientation dispersion index over time (p < .0001).DiscussionThe observed longitudinal changes in our volleyball cohort likely reflect normal development in this age range, while the relative attenuation of these effects seen in football, and especially concussed athletes, could possibly reveal diminished myelination, altered axonal calibers, or depressed pruning processes leading to a static, non-decreasing axonal dispersion. This prospective longitudinal study demonstrates significantly divergent tract-specific trajectories of brain microstructure, possibly reflecting a concussive and/or repeated sub-concussive impact-related alteration of normal white matter development in football athletes.

Small-angle scattering tensor tomography allows for tomographic reconstruction of the 3D reciprocal space from voxels within a bulk volume. In this study, the nanostructure orientation and the scattering curve along different 3D directions are validated with data obtained from thin sections of the same sample., Small-angle scattering tensor tomography (SASTT) is a recently developed technique able to tomographically reconstruct the 3D reciprocal space from voxels within a bulk volume. SASTT extends the concept of X-ray computed tomography, which typically reconstructs scalar values, by reconstructing a tensor per voxel, which represents the local nanostructure 3D organization. In this study, the nanostructure orientation in a human trabecular-bone sample obtained by SASTT was validated by sectioning the sample and using 3D scanning small-angle X-ray scattering (3D sSAXS) to measure and analyze the orientation from single voxels within each thin section. Besides the presence of cutting artefacts from the slicing process, the nanostructure orientations obtained with the two independent methods were in good agreement, as quantified with the absolute value of the dot product calculated between the nanostructure main orientations obtained in each voxel. The average dot product per voxel over the full sample containing over 10 000 voxels was 0.84, and in six slices, in which fewer cutting artefacts were observed, the dot product increased to 0.91. In addition, SAXS tensor tomography not only yields orientation information but can also reconstruct the full 3D reciprocal-space map. It is shown that the measured anisotropic scattering for individual voxels was reproduced from the SASTT reconstruction in each voxel of the 3D sample. The scattering curves along different 3D directions are validated with data from single voxels, demonstrating SASTT’s potential for a separate analysis of nanostructure orientation and structural information from the angle-dependent intensity distribution.

Hippocampal injury is common in traumatic brain injury (TBI) patients, but the underlying pathogenesis remains elusive. In this study, we hypothesize that the presence of the adjacent fluid-containing temporal horn exacerbates the biomechanical vulnerability of the hippocampus. Two finite element models of the human head were used to investigate this hypothesis, one with and one without the temporal horn, and both including a detailed hippocampal subfield delineation. A fluid-structure interaction coupling approach was used to simulate the brain-ventricle interface, in which the intraventricular cerebrospinal fluid was represented by an arbitrary Lagrangian-Eulerian multi-material formation to account for its fluid behavior. By comparing the response of these two models under identical loadings, the model that included the temporal horn predicted increased magnitudes of strain and strain rate in the hippocampus with respect to its counterpart without the temporal horn. This specifically affected cornu ammonis (CA) 1 (CA1), CA2/3, hippocampal tail, subiculum, and the adjacent amygdala and ventral diencephalon. These computational results suggest that the presence of the temporal horn exacerbate the vulnerability of the hippocampus, highlighting the mechanobiological dependency of the hippocampus on the temporal horn.

Finite element (FE) models of the human head are valuable instruments to explore the mechanobiological pathway from external loading, localized brain response, and resultant injury risks. The injury predictability of these models depends on the use of effective criteria as injury predictors. The FE-derived normal deformation along white matter (WM) fiber tracts (i.e., tract-oriented strain) recently has been suggested as an appropriate predictor for axonal injury. However, the tract-oriented strain only represents a partial depiction of the WM fiber tract deformation. A comprehensive delineation of tract-related deformation may improve the injury predictability of the FE head model by delivering new tract-related criteria as injury predictors. Thus, the present study performed a theoretical strain analysis to comprehensively characterize the WM fiber tract deformation by relating the strain tensor of the WM element to its embedded fiber tract. Three new tract-related strains with exact analytical solutions were proposed, measuring the normal deformation perpendicular to the fiber tracts (i.e., tract-perpendicular strain), and shear deformation along and perpendicular to the fiber tracts (i.e., axial-shear strain and lateral-shear strain, respectively). The injury predictability of these three newly proposed strain peaks along with the previously used tract-oriented strain peak and maximum principal strain (MPS) were evaluated by simulating 151 impacts with known outcome (concussion or non-concussion). The results preliminarily showed that four tract-related strain peaks exhibited superior performance than MPS in discriminating concussion and non-concussion cases. This study presents a comprehensive quantification of WM tract-related deformation and advocates the use of orientation-dependent strains as criteria for injury prediction, which may ultimately contribute to an advanced mechanobiological understanding and enhanced computational predictability of brain injury.

Η φιλοσοφική σκέψη υπήρξε ανθρωποκεντρική με ιδιάζοντα τρόπο και επιπλέον η φιλοσοφία υπήρξε το θεμέλιο πάνω στο οποίο στηρίχτηκε ο πνευματικός και ειδικός τεχνικός πολιτισμός, ο γνωστός ως ορθολογιστικός, που εφαρμόζεται στην επιστήμη και που προϋποθέτει την ανεπανάληπτη και κυρίαρχη θέση του ανθρώπου απέναντι στις ζωικές και υλικές υποστάσεις και στα φυσικά φαινόμενα. Στα έργα του Πλάτωνα υπάρχει μια αξιολογική προτεραιότητα του πνεύματος απέναντι στην ύλη, που όμως δεν ενέπνεε την χωρίς όρια απαξίωση ή απομύζηση της υλικής δημιουργίας. Στον Αριστοτέλη η ύλη δεν είναι κάτι το απλώς υπάρχον αλλά το καθ’ ύλην υπάρχον, δηλαδή η δυνατότητα υπάρξεως από της ουσίας στη μορφή μέσω της κίνησης που αποτελεί την ουσία των όντων. Η μεσαιωνική και νεότερη δυτικοευρωπαϊκή φιλοσοφία λόγω της παρεμβολής μιας σφαλερής πνευματοκρατικής χριστιανικής κοσμοθεωρίας ξεστράτισε μονομερώς στον άκρατο ανθρωποκεντρικό ορθολογιστικό μονισμό. Ούτε ο ρομαντισμός ούτε ο επιστημονικός υλισμός μπόρεσαν να αποκαταστήσουν την ορθή σχέση πνεύματος και ύλης. Μια από τις αιτίες που οδήγησαν στην οικολογική κρίση είναι ο ρόλος της θρησκείας και ιδιαίτερα του χριστιανισμού. Οι παρερμηνείες και οι διαφορετικές αντιλήψεις δημιούργησαν μια σύγχυση στην όλη άποψη περί χριστιανισμού και φύσης κυρίως στον τρόπο που η δυτική σκέψη την αντιλήφθηκε. Ο LynnWhite καθηγητής ιστορίας στο Πανεπιστήμιο της Καλιφόρνιας αναφέρει στο πόρισμα της έρευνάς του ότι η ιουδαιοχριστιανική θρησκεία κατέστρεψε τον πλανήτη, επειδή τοποθέτησε τον άνθρωπο στο κέντρο όλων των πραγμάτων. Ο John Passmore, περίπου δέκα χρόνια μετά τον White, κατέληξε στο συμπέρασμα πως υπάρχει μια κυρίαρχη γραμμή σκέψης στην Αγία Γραφή, η οποία θεωρεί τον άνθρωπο ως Δεσπότη, που υποτάσσει τη φύση και τη μεταχειρίζεται, όπως του αρέσει. Δίπλα σε αυτήν υπάρχουν και δύο μειοψηφικές γραμμές σκέψης: η μία αναδεικνύει τον άνθρωπο ως συνεργάτη της φύσης, που προσπαθεί να την τελειοποιήσει και η άλλη διατείνεται πως ο άνθρωπος έρχεται στον κόσμο με σκοπό να γίνει καλός διαχειριστής της θεϊκής παρουσίας, ένα είδος οικονόμου. Τέλος η Palmer ισχυρίζεται πως ο όρος «εποπτεία» πουθενά στη Βίβλο δεν χρησιμοποιείται σε σχέση με τη φύση. Επιμένει η Ρalmer ότι, η χρησιμοποίηση του όρου διαχείριση, στον καθημερινό πολιτικό λόγο μπορεί να εκπέσει σ΄ έναν ηθικό όρο που να σημαίνει οτιδήποτε για τον οποιονδήποτε, που να δίνει συγχωροχάρτι σε οποιονδήποτε επικαλείται αυτή τη "σώφρονα" διαχείριση και να νομιμοποιεί τη συνηθισμένη επιθετική στάση απέναντι στη φύση. Για τη χριστιανική θεολογία αποτελεί προϋπόθεση ότι ο κόσμος δημιουργήθηκε «εκ του μηδενός» με την απόλυτη έννοια της λέξεως, ένα δόγμα που ξεχωρίζει το Χριστιανισμό από τις ειδωλολατρικές θρησκείες και φιλοσοφίες. Το γεγονός ότι στην εποχή μας η επιστήμη της φυσικής δεν το βρίσκει αδιανόητο ότι ο κόσμος δημιουργήθηκε από το απόλυτο μηδέν, μπορεί να είναι ένας θετικός παράγοντας για τη θεολογία, ώστε να αρχίσει οικοδομητική συζήτηση με τους φυσικούς επιστήμονες. Αλλά ακόμα και αν διαφωνούν οι επιστήμονες με το δόγμα αυτό, οι χριστιανοί θεολόγοι αποδεχόμενοι αυτό από την αρχή, θα πρέπει να είναι κατά πάντα συνεπείς σ' αυτό. Αυτή η συνέπεια είναι ανάγκη να είναι επίσης εμφανής στην προσπάθεια να απαντηθεί το ερώτημα: πώς έβλεπε ο Θεός τη δυνατότητα της σωτηρίας του κόσμου, όταν τον δημιουργούσε από το μηδέν; Θα ήταν αντιφατικό να υποθέσει κανείς ότι ο Θεός προίκισε τον κόσμο με φυσική δυνατότητα σωτηρίας, γιατί μια τέτοια προϋπόθεση θα υπονοούσε ότι ανάμεσα στο Θεό και τον κόσμο υπάρχει μια φυσική «συγγένεια» (όπως θα την έλεγαν οι αρχαίοι Έλληνες). Κάθε φυσική ομοιότητα ανάμεσα στο Θεό και τη δημιουργία θα έκανε με ένα ουσιαστικό τρόπο, τις δύο πραγματικότητες μία. Γι' αυτό ακριβώς οι Πατέρες απέρριψαν την νεοπλατωνική θεωρία των απορροών και την πλατωνική και ωριγενική θεωρία της αιωνιότητας των ψυχών, καθώς και την αριστοτελική ιδέα της αιωνιότητας της ύλης. Είναι θέμα λογικής συνέπειας για τους Χριστιανούς να αναζητηθεί η σωτηρία της δημιουργίας σε τρόπους άλλους από αυτούς. Αλλά, αν αποκλειστεί η προϋπόθεση ότι ο κόσμος έχει στη φύση του κάποιους παράγοντες που του εξασφαλίζουν τη σωτηρία και την αιωνιότητα, και, παρ' όλα αυτά, επιμείνουμε στην αιώνια σωτηρία του κόσμου, δεν υπάρχει παρά μόνο μια λύση: να βρεθεί ένας τρόπος να συνδεθεί ο κόσμος με το Θεό, το μόνο αιώνιο και αθάνατο Ον, χωρίς να παρεμβάλουμε καμμιά «φυσική συγγένεια». Πρέπει να βρεθεί ένας συνδετικός κρίκος ανάμεσα στα δύο, το Θεό και τον κόσμο, που θα μπορούσε να διασφαλίσει την επικοινωνία της ζωής ανάμεσα τους, χωρίς να καταστρέψει τη φυσική ετερότητα του Θεού και της δημιουργίας. Μπορεί να βρεθεί ένας τέτοιος κρίκος; Μπορεί να έχει κάποιο νόημα ένας τέτοιος σύνδεσμος;Το χριστιανικό δόγμα προσφέρει ως λύση στο πρόβλημα αυτό τη θέση του ανθρώπου στη δημιουργία. Ο άνθρωπος είναι εκείνος, στον οποίο πρέπει να αναζητηθεί ο συνδετικός κρίκος ανάμεσα στο Θεό και τον κόσμο, και είναι αυτό ακριβώς που κάνει τον άνθρωπο υπεύθυνο, μάλιστα τον μόνο μέσα στην κτίση υπεύθυνο για την τύχη της δημιουργίας. Η Χριστιανική πίστη θεωρεί πως η οικολογική κρίση είναι κρίση πολιτισμού. Είναι μια κρίση, η οποία έχει να κάνει με την απώλεια της ιερότητας της φύσεως στον πολιτισμό μας. Μόνο δύο δρόμους μπορεί να δει κανείς για το ξεπέρασμα αυτής της κρίσεως. Ο ένας είναι ο δρόμος της ειδωλολατρίας. Ο ειδωλολάτρης θεωρεί τον κόσμο ιερό, γιατί τον βλέπει διαποτισμένο από τη θεία παρουσία. Επομένως, τον σέβεται και δεν τον καταστρέφει. Αλλά κατά τον ίδιο τρόπο, δεν ανησυχεί ποτέ και για την τύχη του, γιατί πιστεύει στην αιωνιότητά του. Δεν βλέπει επίσης καμμιά ανάγκη για μετασχηματισμό της φύσεως ή για υπέρβαση των ορίων της: ο κόσμος είναι καλός, όπως είναι, και κατέχει εκ φύσεως ό,τι χρειάζεται, για να επιζήσει. Ο άλλος δρόμος είναι αυτός που έχει περιγραφεί εδώ ως τη χριστιανική τοποθέτηση. Ο Χριστιανός σέβεται τον κόσμο ως ιερό, όχι γιατί ενέχει στη φύση του την παρουσία του Θεού, αλλά γιατί βρίσκεται σε διαλεκτική σχέση με το Θεό. Έτσι σέβεται τον κόσμο αλλά θεωρεί τον άνθρωπο το μόνο δυνατό συνδετικό κρίκο ανάμεσα στο Θεό και στη δημιουργία. Ο άνθρωπος γίνεται έτσι ένας σύνδεσμος, που μπορεί ή να φέρει την υλική φύση σε κοινωνία με το Θεό και με τον τρόπο αυτό να την αγιάσει ή να την στρέψει τελικά προς τον άνθρωπο -ή προς την ίδια τη φύση- και να την καταδικάσει να γίνει «κάτι», ένα «αντικείμενο», του οποίου το νόημα και ο σκοπός εξαντλούνται στην ικανοποίηση του ανθρώπου. Από τους δύο αυτούς τρόπους ο δεύτερος, ο χριστιανικός, είναι εκείνος που προσδίδει στον άνθρωπο βαριά ευθύνη για την τύχη της δημιουργίας. Ο πρώτος, ο ειδωλολατρικός, βλέπει τον άνθρωπο σαν μέρος του κόσμου• ο δεύτερος, με το να βλέπει τον άνθρωπο ως κρίκο ανάμεσα στον κόσμο και το Θεό, τον βλέπει ως το μοναδικό πρόσωπο στη δημιουργία, δηλαδή ως τον μόνο που σέβεται βαθιά τον απρόσωπο κόσμο, όχι μόνο για να τον «διατηρήσει», αλλά για να τον καλλιεργεί και να τον ενσωματώνει σε μορφές πολιτισμού, οι οποίες θα τον ανυψώσουν στο δικό του επίπεδο, σε αιώνια επιβίωση και σωτηρία. Είναι αλήθεια ότι διαπιστώνονται επιδράσεις της αρχαίας ελληνικής φιλοσοφίας στη διαμόρφωση των ηθικών θεωριών περί φύσεως στη βυζαντινή φιλοσοφία και την πατερική γραμματεία. Ο Γαληνός, χαρακτηρίζει τους ιατρούς ως υπηρέτες της φύσης. Αυτό συνδέεται με τη βυζαντινή θεώρηση ότι ο άνθρωπος είναι επόπτης και επιστάτης της φύσης. Οι ιδέες επιπλέον πως η φύση διδάσκει στα έμβια όντα και ειδικά στον έλλογο άνθρωπο τις ενέργειες που συνιστούν τους μηχανισμούς επιβίωσής του και πως ο άνθρωπος οφείλει να χρησιμοποιεί τα πλεονεκτήματα και τις παροχές της φύσης κατάλληλα με συμβούλους του την εμπειρία και το λογικό του, αποτυπώνουν σχεδόν πανομοιότυπα το χαρακτήρα της επιστασίας, που υποτίθεται πως οδηγεί στη μελέτη και τη σπουδή της γνώσης των αρχών και των νόμων που διέπουν την κτιστή δημιουργία. Στον Τίμαιο, ο Πλάτων έδειξε πως είναι δυνατόν να έχει ο άνθρωπος μια ιδιαίτερα ευνοϊκή στάση για το περιβάλλον, να αποδέχεται τη μεταφυσική αρχή του αγαθού, αλλά παράλληλα να πιστεύει και στην ενύπαρξη της ωραιότητας στη φύση και να ενδιαφέρεται για αυτήν. Το κατεξοχήν ηθικό πρόβλημα της οικολογικής κρίσης συνάπτεται με το γεγονός ότι ο άνθρωπος έχει ανατρέψει την ιεραρχία των δυνάμεων της ψυχής του και των συστοίχων προς αυτή αξιών, τρόπων και μορφών ζωής κι έχει ξεφύγει από το δρόμο που οδηγεί στην πραγματική ψυχική ευδαιμονία, που είναι να ζει σύμφωνα με την αρετή. Η προτεραιότητα του ηθικού βίου μέσα στην πολιτική κοινωνία πρέπει να είναι απόλυτη, για να υπάρξει δυνατότητα υπέρβασης της οικολογικής κρίσης. Η ιδέα αυτή συνάπτεται με την αντίστοιχη της βυζαντινής φιλοσοφίας, πως υπεύθυνη για την οικολογική κρίση είναι η απομάκρυνση του ανθρώπου από το Θεό. Μια ακόμη διδασκαλία που έχει αφήσει το αποτύπωμά της στη χριστιανική θεολογία είναι η Παύλειος διδασκαλία. Σύμφωνα με τη διδασκαλία του αποστόλου Παύλου, ολόκληρη η κτίση, πνευματική και υλική, δημιουργήθηκε από το Λόγο του Θεού και έχει ως συγκεκριμένο σκοπό να μετάσχει στη δόξα Του: «Τα πάντα δι’ αυτού και εις αυτόν έκτισται». Όλα τα όντα συνδέονται αρμονικά μεταξύ τους, γιατί έχουν το λόγο της υπάρξεως και της παρουσίας τους στον προαιώνιο δημιουργικό Λόγο του Θεού. Από Αυτόν προέρχονται, προς Αυτόν κατευθύνονται και από Αυτόν λογοποιούνται τα πάντα. Η έννοια και ο σκοπός της δημιουργίας δεν μπορούν να προσδιορισθούν χωρίς τον Θεό Λόγο. Γι’ αυτό λογικός δεν είναι μόνο ο άνθρωπος αλλά και η υπόλοιπη δημιουργία του Θεού. Άλλωστε και η υπεροχή του ανθρώπου σε σχέση με τη συνήθως αποκαλούμενη «άλογη» κτίση δεν δικαιολογείται τόσο από τη λογικότητα της κατασκευής του ανθρώπου ούτε βέβαια από την κτιστή λογική του, όσο από την ιδιαίτερη σχέση του με τον άκτιστο Λόγο του Θεού, που υπάρχει ως αρχέτυπο του και τον Οποίο εικονίζει. Η σχέση του ανθρώπου με την υπόλοιπη κτίση πιστοποιείται από την ίδια τη φυσιολογία του. Ο άνθρωπος είναι ύπαρξη διμερής, ταυτόχρονα βιολογική και πνευματική. Ο Θεός, σύμφωνα με την περιγραφή της Γενέσεως, έπλασε τον άνθρωπο παίρνοντας χώμα από τη γη και εμφυσώντας το πρόσωπό του μετέδωσε σ’ αυτόν το πνεύμα, για να γίνει έτσι ζωντανή, υλικοπνευματική ύπαρξη. Στην υλικότητα και χοϊκότητα του ανθρώπου αναφέρεται και ο απόστολος Παύλος. Βασικό δομικό υλικό του είναι το χώμα, δηλαδή τα φυσικά και βιολογικά του στοιχεία. Από την άποψη αυτή αποτελεί μέρος της φυσικής δημιουργίας και βιολογική ύπαρξη, που ως προς τη δομή και τη λειτουργία της δεν διαφέρει πολύ από τις υπόλοιπες φυσικές υπάρξεις. Η υλικότητά του, παρότι διαθέτει ανώτερη μορφή και ποιότητα από την υλικότητα των φυτών και των ζώων, είναι βασικό και αναφαίρετο στοιχείο της υπάρξεως του, έτσι ώστε να μη νοείται ο άνθρωπος χωρίς τη φυσική και βιολογική του υπόσταση. Στον άνθρωπο βρίσκονται όλα τα επίπεδα της υπάρξεως από τις διάφορες μορφές του κτιστού κόσμου• γι’ αυτό και η φυσιολογία του έχει άμεση σχέση και ενδιαφέρει την ορθόδοξη κοσμολογία.Μετά από τη χριστιανική τοποθέτηση το οικολογικό πρόβλημα τίθεται υπο το πρίσμα της σύγχρονης οικολογικής φιλοσοφίας. Πρωταρχικός σκοπός της οικολογικής ηθικής πρέπει και μπορεί να είναι η επιβίωση και η άνθιση της ζωής στον πλανήτη μας. Θα ήταν άσκοπο, ατελέσφορο, όσο και επιζήμιο να επιφορτιστεί η οικολογική ηθική με καθήκοντα και υποχρεώσεις που ανήκουν σε ένα ευρύτερο πλαίσιο στοχασμού. Εάν ο σκοπός είναι ο προαναφερθείς, το μόνο που απαιτείται είναι ο τρόπος επίτευξής του. Και ο τρόπος αυτός δεν είναι άλλος από τη διαμόρφωση μιας επαρκούς ηθικής δομής, ικανής να υποστηρίξει τη διάσωση ή τη διατήρηση του περιβάλλοντος. Για να είναι επαρκής μια τέτοια δομή, πρέπει να είναι συμπαγής και να έχει ευρεία εφαρμογή. Τέλος αν ένα ηθικό σύστημα επιθυμεί να είναι συμπαγές και ευρύ-περιεκτικό, πρέπει να είναι επαγωγικό, σταθερό, καθοδηγητικό και σε καμία περίπτωση αντιφατικό. Επαγωγική η ηθική πρέπει να είναι όχι τόσο στην κατεύθυνση της στόχευσής της, όσο στη μεθοδολογία της. Το κάθε βήμα πρέπει ν’ ακολουθείται από το επόμενο κατά λογική αλληλουχία και όχι με άλματα αλλά με βηματισμό αργό από τα απλά προς τα πιο σύνθετα ζητήματα, ώστε ο βασικός στόχος και οι αρχές να μένουν πάντα ευκρινείς. Στην ουσία της ηθικής βρίσκεται η δυνατότητα και το καθήκον της καθοδήγησης. Αν επιθυμεί να επιτύχει κάτι τέτοιο η οικολογική Ηθική, είναι υποχρεωμένη να αναγνωρίσει απόλυτη αξία στον περιβάλλοντα κόσμο και σε ότι τον αποτελεί, άψυχη ύλη, ασυνείδητη και ενσυνείδητη μη ανθρώπινη ζωή και τελικώς στην ανθρώπινη ύπαρξη. Philosophical thinking was anthropocentric in an unusual way. In addition, philosophy was the foundation upon which the spiritual and technical civilization, known as rationalistic, was built and which applies in science and assumes the unique and dominant position of man against animal and material existence and natural phenomena. In Plato's work, there is an evaluative priority of spirit against matter which, however, did not inspire the limitless disdain or exploitation of material creation. For Aristotle, prime matter is not something merely existing but existing materially, that is, the ability of existence through movement which is the essence of beings. Medieval and modern Western European philosophy deviated unilaterally towards the unrestrained anthropocentric rationalistic monism due to the interference of a mistaken Christian spiritualistic worldview. Neither romanticism nor scientific materialism were able to restore the right relationship between spirit and matter.One of the reasons behind the ecological crisis is the role played by religion, Christianity in particular. Misinterpretations and different beliefs created a confusion regarding Christianity and nature, mainly in the way it was perceived by the western way of thinking. Lynn White, Professor of History in the University of California, mentions in the conclusion of his research that the Jewish-Christian religion brought about the destruction of the planet by placing man in the center of all things. About ten years after White, John Passmore concluded that there is a dominant line of thought in the Holy Scripture which regards man as a Despot who subjugates nature, treating it however he likes. Next to it, there are also two lesser lines of thought: the first one shows man as nature's collaborator, trying to perfect it, and the other contends that man comes to this world in order to become a good administrator of the divine presence, a kind of housekeeper. Lastly, Palmer claims that nowhere in the Bible is the term "supervision" used in connection with nature. Palmer insists that the use of the term "administration" in everyday speech can result in an ethical term which would mean anything to anyone, which would give an absolution certificate to those who use it and would justify the usual aggressive attitude towards nature.For the Christian religion, it is a prerequisite that the world was created "ex nihilo" in the absolute meaning of the word, a doctrine which distinguishes Christianity from the idolatrous religions and philosophies. The fact that nowadays the science of physics does not consider inconceivable the fact that the world was created ex nihilo may be a positive factor for theology so that it can commence a constructive conversation with physicists. However, even if scientists disagree with this doctrine, Christian theologists, taking this for granted, should remain consistent with it. It is essential that this consistency be obvious when trying to answer the question: how did God view the possibility of the world's salvation when He created it ex nihilo?It would be contradictory to presume that God blessed this world with a natural ability for salvation because such a prerequisite would imply that there is a natural "blood relation" (as ancient Greeks would call it) between God and the world. Any natural resemblance between God and His creation would essentially turn these two realities into one. That's exactly why the Fathers rejected not only the neoplatonic emanationism as well as Plato's and Horigenes' theory of the eternity of souls but also the aristotelian idea of eternity of matter. It is a matter of logical consequence for Christians to seek the salvation of creation in ways different from these.However, should the prerequisite that the world has some factors which ensure its salvation and eternity be excluded, and, still, we continue to insist on the eternal salvation of the world, there is but one solution: to find a way to connect the world with God, the only eternal, immortal being, leaving out any "natural blood relation". A link should be found between God and the world, which could ensure the communication of life between them, without destroying the natural dissimilarity between God and creation. Can such a link be found? Would there be a meaning in such a connection? The Christian doctrine's solution to this problem lies in man's position in creation. Man is the one responsible for the missing link between God and the world, and this is exactly what holds man responsible, indeed, the only one responsible for the fate of creation.The Christian faith sees the ecological crisis as a crisis of civilization which resulted from the loss of the sanctity of nature in our civilization. And this crisis can be overcome in two ways. The first one is idolatry. Idolaters regard the world as holy because they see it imbued with divine presence. Consequently, they respect it and they do not destroy it. At the same time, however, they are not concerned about its fate, since they believe in its eternity. In addition, they do not see the need for transforming nature or exceeding its limits: the world is good as it is, and naturally possesses the means for its survival. The second way is the one described as the Christian stance. Christians respect the world as holy, not because it naturally involves God's presence, but because it is in a dialectical relationship with God. Thus, they respect the world but consider man the only possible missing link between God and creation, who can either bring material nature in communion with God and in this way sanctify it or turn it against man - or against nature itself - and doom it to become "something", an "object", whose meaning and purpose are used in satisfying man.Of the two ways, it is the Christian one which holds man immensely responsible for the fate of creation. The first one, the idolatrous, considers man part of this world; the second one, by considering man a link between God and the world, it sees man as the sole person in creation, which means the only one who deeply respects the impersonal world, not only in order to "preserve" it but also in order to integrate it in forms of civilization which will elevate it to his level, to eternal survival and salvation.It is true that the influence of ancient greek philosophy is obvious in the formulation of ethical theories concerning nature in byzantine philosophy and patristic literature. Galen characterizes physicians as servants of nature. This has to do with the the byzantine concept that man is the supervisor and caretaker of nature. In addition, the idea that nature teaches living beings, rational human beings in particular, the actions necessary for its survival mechanisms as well as the idea that man has to use nature's advantages and provisions appropriately using his experience and logic illustrate almost identically the nature of supervision which supposedly leads to the study of the knowledge of principles and laws which govern creation. In Timaeus, Plato proved that it is possible for man to hold a favorable attitude towards the environment, to accept the metaphysical concept of the Form of the Good (Agathon), but, at the same time believe that pulchritude is inherent in nature and be interested in it. Τhe main ethical problem of the ecological crisis has to do with the fact that man has subverted the hierarchy of the power of his soul and the values, ways and forms of life which agree with it, thus deviating from the path leading to the true mental well-being, that is, to live according to righteousness. There should be a priority of moral life in the civil society in order to overcome the ecological crisis. This idea is in accordance with the byzantine philosophy which blames the estrangement from God for the ecological crisis.Apostle Paul's teaching is yet another teaching which has left its mark in Christian theology, according to which the whole of God's creation, both spiritual and material, was created by the Word of God with the sole purpose to partake of His glory: "All creatures are from Him, through Him and to Him". All creatures are in harmony because the reason for their existence and presence lies in the eternal Word of God. Everything comes from Him, is intended for Him and is brought to life. The meaning and purpose of creation cannot be defined without the Word of God. Thus, not only man but also the rest of God's creation is rational. After all, man's superiority over the often called "non-rational" creation is justified neither by the logicality of his making nor by his created logic but by his special relationship with the archetypal uncreated Word of God Which he depicts. Man's relationship with the rest of the creation is certified by his very physiology. Man is a dual being, biological and spiritual at the same time. According to Genesis, God formed man of dust by breathing spirit into his face, thus making him a live, spiritual and corporeal being. Apostle Paul also refers to man's corporeality and earthiness. Earth is his main construction material, that is, his natural and biological elements. From this aspect, man is part of the natural creation and he is a biological being whose structure and function are not much different from the rest of the natural beings. Although his corporeality is superior in form and quality to that of plants and animals, it is a basic, inalienable element of his existence, so that man cannot be perceived without his natural and biological being. All levels of being from different forms of the created world are found in man; that's the reason why his physiology interests and is directly related to the orthodox cosmology. According to the Christian stance, the ecological problem is put through the prism of modern ecological philosophy.The primary goal of ecological ethics should and can be the survival and prosperity of life on our planet. It would be pointless, ineffective and detrimental to surcharge ecological ethics with the duties and obligations which belong to a wider frame of contemplation. Keeping this goal in mind, the only thing left is to find a way to achieve it. And the only way to do so is to formulate a structure able to save and conserve the environment. For such a structure to be adequate, it should be compact and have a wide application. Lastly, if an ethical system wishes to be compact and comprehensive, it needs to be inferential, stable, guiding but, in no way, contradictory. Ethics needs to be inferential not so much in the direction of its contemplation as in its methodology. Each step should be followed by the next using a logical sequence, not with big leaps but at a slow pace leading from simple to more compex matters, so that the main goal and principles remain clear. The essence of ethics is the ability and the duty of guidance. Should ecological ethics desire to achieve this, it has to recognise absolute value to the surrounding world and everything it is composed of, inanimate matter, conscious and unconscious human life and, lastly, human existence.

A fast and robust reconstruction algorithm for small-angle scattering tensor tomography, named iterative reconstruction tensor tomography, is presented. It employs a second-rank tensor model and an iterative error backpropagation to simplify and accelerate tensor tomography reconstruction., The recent advent of tensor tomography techniques has enabled tomographic investigations of the 3D nanostructure organization of biological and material science samples. These techniques extended the concept of conventional X-ray tomography by reconstructing not only a scalar value such as the attenuation coefficient per voxel, but also a set of parameters that capture the local anisotropy of nanostructures within every voxel of the sample. Tensor tomography data sets are intrinsically large as each pixel of a conventional X-ray projection is substituted by a scattering pattern, and projections have to be recorded at different sample angular orientations with several tilts of the rotation axis with respect to the X-ray propagation direction. Currently available reconstruction approaches for such large data sets are computationally expensive. Here, a novel, fast reconstruction algorithm, named iterative reconstruction tensor tomography (IRTT), is presented to simplify and accelerate tensor tomography reconstructions. IRTT is based on a second-rank tensor model to describe the anisotropy of the nanostructure in every voxel and on an iterative error backpropagation reconstruction algorithm to achieve high convergence speed. The feasibility and accuracy of IRTT are demonstrated by reconstructing the nanostructure anisotropy of three samples: a carbon fiber knot, a human bone trabecula specimen and a fixed mouse brain. Results and reconstruction speed were compared with those obtained by the small-angle scattering tensor tomography (SASTT) reconstruction method introduced by Liebi et al. [Nature (2015 ▸), 527, 349–352]. The principal orientation of the nanostructure within each voxel revealed a high level of agreement between the two methods. Yet, for identical data sets and computer hardware used, IRTT was shown to be more than an order of magnitude faster. IRTT was found to yield robust results, it does not require prior knowledge of the sample for initializing parameters, and can be used in cases where simple anisotropy metrics are sufficient, i.e. the tensor approximation adequately captures the level of anisotropy and the dominant orientation within a voxel. In addition, by greatly accelerating the reconstruction, IRTT is particularly suitable for handling large tomographic data sets of samples with internal structure or as a real-time analysis tool during the experiment for online feedback during data acquisition. Alternatively, the IRTT results might be used as an initial guess for models capturing a higher complexity of structural anisotropy such as spherical harmonics based SASTT in Liebi et al. (2015 ▸), improving both overall convergence speed and robustness of the reconstruction.

Finite element (FE) models of the human head are valuable instruments to explore the mechanobiological pathway from external loading, localized brain response, and resultant injury risks. The injury predictability of these models depends on the use of effective criteria as injury predictors. The FE-derived normal deformation along white matter (WM) fiber tracts (i.e., tract-oriented strain) has recently been suggested as an appropriate predictor for axonal injury. However, the tract-oriented strain only represents a partial depiction of the WM fiber tract deformation. A comprehensive delineation of tract-related deformation may improve the injury predictability of the FE head model by delivering new tract-related criteria as injury predictors. Thus, the present study performed a theoretical strain analysis to comprehensively characterize the WM fiber tract deformation by relating the strain tensor of the WM element to its embedded fiber tracts. Three new tract-related strains were proposed, measuring the normal deformation vertical to the fiber tracts (i.e., tract-vertical strain), and shear deformation along and vertical to the fiber tracts (i.e., axial-shear strain and lateral-shear strain, respectively). The injury predictability of these three newly-proposed strain peaks along with the previously-used tract-oriented strain peak and maximum principal strain (MPS) were evaluated by simulating 151 impacts with known outcome (concussion or no-concussion). The results showed that four tract-related strain peaks exhibit superior performance compared to MPS in discriminating concussion and non-concussion cases. This study presents a comprehensive quantification of WM tract-related deformation and advocates the use of orientation-dependent strains as criteria for injury prediction, which may ultimately contribute to an advanced mechanobiological understanding and enhanced computational predictability of brain injury. HighlightO_LIDeformation of white matte fiber tracts is directly related to brain injury, but only partially analyzed thus far. C_LIO_LIA theoretical derivation that comprehensively characterizes white matter tract-related deformation is conducted. C_LIO_LIAnalytical formulas of three novel tract-related strains are presented. C_LIO_LITract-related strain peaks are better predictors for concussion than the maximum principal strain. C_LI

Batrachochytrium salamandrivorans (Bsal) has been assessed according to the criteria of the Animal Health Law (AHL), in particular criteria of Article 7 on disease profile and impacts, Article 5 on the eligibility of Bsal to be listed, Article 9 for the categorisation of Bsal according to disease prevention and control rules as in Annex IV, and Article 8 on the list of animal species related to Bsal. The assessment has been performed following a methodology composed of information collection and compilation, expert judgement on each criterion at individual and, if no consensus was reached before, also at collective level. The output is composed of the categorical answer, and for the questions where no consensus was reached, the different supporting views are reported. Details on the methodology used for this assessment are explained in a separate opinion. According to the assessment performed, Bsal can be considered eligible to be listed for Union intervention as laid down in Article 5(3) of the AHL. The disease would comply with the criteria as in sections 4 and 5 of Annex IV of the AHL, for the application of the disease prevention and control rules referred to in points (d) and (e) of Article 9(1). The assessment here performed on compliance with the criteria as in Section 1 of Annex IV referred to in point (a) of Article 9(1) is inconclusive. The animal species to be listed for Bsal according to Article 8(3) criteria are species of the families Salamandridae and Plethodontidae as susceptible and Salamandridae and Hynobiidae as reservoirs.

123 pages, 20 tables, 16 figures, 2 appendix.-- Open access, On-land transport/storage of fresh fishery products (FFP) for up to 3 days in ‘tubs’ of three-layered polyethylene filled with freshwater and ice was compared to the currently authorised practice (fish boxes of high-density poly-ethylene filled with ice). The impact on the survival and growth of biological hazards in fish and the histamine production in fish species associated with a high amount of histidine was assessed.In different modelling scenarios, the FFP are stored on-board in freshwater or seawater/ice (in tubs) and once on-land they are ‘handled’ (i.e. sorted or gutted and/or filleted) and transferred to either tubs or boxes. The temperature of the FFP was assumed to be the most influential factor affecting relevant hazards. Under reasonably foreseeable ‘abusive’ scenarios and using a conservative modelling approach, the growth of the relevant hazards (i.e. Listeria monocytogenes, Aeromonas spp. and non-proteolytic Clostridium botulinum), is expected to be < 0.2 log10 units higher in tubs than in boxes after 3 days when the initial temperature of the fish is 0°C (‘keeping’ process). Starting at 7°C (‘cooling-keeping’ process), the expected difference in the growth potential is higher (< 1 log10 for A. hydrophila and < 0.5 log10 for the other two hazards) due to the poorer cooling capacity of water and ice (tub) compared with ice (box). The survival of relevant hazards is not or is negligibly impacted. Histamine formation due to growth of Morganella psychrotolerans under the ‘keeping’ or ‘cooling-keeping’ process can be up to 0.4 ppm and 1.5 ppm higher, respectively, in tubs as compared to boxes after 3 days, without reaching the legal limit of 100 ppm. The water uptake associated with the storage of the FFP in tubs (which may be up to 6%) does not make a relevant contribution to the differences in microbial growth potential compared to boxes

While diffusion MRI (dMRI) is currently the method of choice to non-invasively probe tissue microstructure and study structural connectivity in the brain, its spatial resolution is limited and its results need structural validation. Current ex vivo methods employed to provide 3D fiber orientations have limitations, including tissue-distorting sample preparation, small field of view or inability to quantify 3D fiber orientation distributions. 3D fiber orientation in tissue sections can be obtained from 3D scanning small-angle X-ray scattering (3D sSAXS) by analyzing the anisotropy of scattering signals. Here we adapt the 3D sSAXS method for use in brain tissue, exploiting the high sensitivity of the SAXS signal to the ordered molecular structure of myelin. We extend the characterization of anisotropy from vectors to tensors, employ the Funk-Radon-Transform for converting scattering information to real space fiber orientations, and demonstrate the feasibility of the method in thin sections of mouse brain with minimal sample preparation. We obtain a second rank tensor representing the fiber orientation distribution function (fODF) for every voxel, thereby generating fODF maps. Finally, we illustrate the potential of 3D sSAXS by comparing the result with diffusion MRI fiber orientations in the same mouse brain. We show a remarkably good correspondence, considering the orthogonality of the two methods, i.e. the different physical processes underlying the two signals. 3D sSAXS can serve as validation method for microstructural MRI, and can provide novel microstructural insights for the nervous system, given the method's orthogonality to dMRI, high sensitivity to myelin sheath's orientation and abundance, and the possibility to extract myelin-specific signal and to perform micrometer-resolution scanning.

Following a request from the European Commission, EFSA assessed the annual post‐market environmental monitoring (PMEM) report for the 2016 growing season of the Cry1Ab‐expressing maize event MON 810 provided by Monsanto Europe S.A. Partial compliance with refuge requirements was reported in Spain, as observed in previous years. EFSA reiterates the need to achieve full compliance in areas of high maize MON 810 adoption to delay resistance evolution, and therefore advocates increasing the level of compliance in such areas. Resistance monitoring data do not indicate a decrease in susceptibility to the Cry1Ab protein in the field corn borer populations tested in the 2016 season. However, EFSA identified some methodological and reporting limitations pertaining to resistance monitoring that need improvement in future PMEM reports. No complaints related to corn borer infestation of maize MON 810 were received via the farmer alert system during the 2016 cultivation season. EFSA encourages the consent holder to provide more information on this complementary resistance monitoring tool. The data on general surveillance do not indicate any unanticipated adverse effects on human and animal health or the environment arising from the cultivation of maize MON 810. EFSA reiterates its recommendations on the methodology and analysis of farmer questionnaires, and considers that future literature searches on maize MON 810 performed in the context of annual PMEM reports should follow the guidelines given in the 2017 EFSA explanatory note on literature searching. Moreover, EFSA encourages relevant stakeholders to implement a methodological framework that enables the use of existing networks in the broader context of environmental monitoring. EFSA concludes that no new evidence has been reported in the 2016 PMEM report that would invalidate previous EFSA evaluations on the safety of maize MON 810.

The mechanical properties of many materials are based on the macroscopic arrangement and orientation of their nanostructure. This nanostructure can be ordered over a range of length scales. In biology, the principle of hierarchical ordering is often used to maximize functionality, such as strength and robustness of the material, while minimizing weight and energy cost. Methods for nanoscale imaging provide direct visual access to the ultrastructure (nanoscale structure that is too small to be imaged using light microscopy), but the field of view is limited and does not easily allow a full correlative study of changes in the ultrastructure over a macroscopic sample. Other methods of probing ultrastructure ordering, such as small-angle scattering of X-rays or neutrons, can be applied to macroscopic samples; however, these scattering methods remain constrained to two-dimensional specimens or to isotropically oriented ultrastructures. These constraints limit the use of these methods for studying nanostructures with more complex orientation patterns, which are abundant in nature and materials science. Here, we introduce an imaging method that combines small-angle scattering with tensor tomography to probe nanoscale structures in three-dimensional macroscopic samples in a non-destructive way. We demonstrate the method by measuring the main orientation and the degree of orientation of nanoscale mineralized collagen fibrils in a human trabecula bone sample with a spatial resolution of 25 micrometres. Symmetries within the sample, such as the cylindrical symmetry commonly observed for mineralized collagen fibrils in bone, allow for tractable sampling requirements and numerical efficiency. Small-angle scattering tensor tomography is applicable to both biological and materials science specimens, and may be useful for understanding and characterizing smart or bio-inspired materials. Moreover, because the method is non-destructive, it is appropriate for in situ measurements and allows, for example, the role of ultrastructure in the mechanical response of a biological tissue or manufactured material to be studied.

Small-angle X-ray scattering tensor tomography, which allows reconstruction of the local three-dimensional reciprocal-space map within a three-dimensional sample as introduced by Liebi et al. [Nature (2015), 527, 349–352], is described in more detail with regard to the mathematical framework and the optimization algorithm. For the case of trabecular bone samples from vertebrae it is shown that the model of the three-dimensional reciprocal-space map using spherical harmonics can adequately describe the measured data. The method enables the determination of nanostructure orientation and degree of orientation as demonstrated previously in a single momentum transfer q range. This article presents a reconstruction of the complete reciprocal-space map for the case of bone over extended ranges of q. In addition, it is shown that uniform angular sampling and advanced regularization strategies help to reduce the amount of data required., Acta Crystallographica Section A: Foundations and Advances, 74 (1), ISSN:2053-2733

Connective tissue aging and diabetes related comorbidity are associated with compromised tissue function, increased susceptibility to injury, and reduced healing capacity. This has been partly attributed to collagen cross-linking by advanced glycation end-products (AGEs) that accumulate with both age and disease. While such cross-links are believed to alter the physical properties of collagen structures and tissue behavior, existing data relating AGEs to tendon mechanics is contradictory. In this study, we utilized a rat tail tendon model to quantify the micro-mechanical repercussion of AGEs at the collagen fiber-level. Individual tendon fascicles were incubated with methylglyoxal (MGO), a naturally occurring metabolite known to form AGEs. After incubation in MGO solution or buffer only, tendons were stretched on the stage of a multiphoton confocal microscope and individual collagen fiber stretch and relative fiber sliding were quantified. Treatment by MGO yielded increased fluorescence and elevated denaturation temperatures as found in normally aged tissue, confirming formation of AGEs and related cross-links. No apparent ultrastructural changes were noted in transmission electron micrographs of cross-linked fibrils. MGO treatment strongly reduced tissue stress relaxation (p

Bone's remarkable mechanical properties are a result of its hierarchical structure. The mineralized collagen fibrils, made up of collagen fibrils and crystal platelets, are bone's building blocks at an ultrastructural level. The organization of bone's ultrastructure with respect to the orientation and arrangement of mineralized collagen fibrils has been the matter of numerous studies based on a variety of imaging techniques in the past decades. These techniques either exploit physical principles, such as polarization, diffraction or scattering to examine bone ultrastructure orientation and arrangement, or directly image the fibrils at the sub-micrometre scale. They make use of diverse probes such as visible light, X-rays and electrons at different scales, from centimetres down to nanometres. They allow imaging of bone sections or surfaces in two dimensions or investigating bone tissue truly in three dimensions, in vivo or ex vivo , and sometimes in combination with in situ mechanical experiments. The purpose of this review is to summarize and discuss this broad range of imaging techniques and the different modalities of their use, in order to discuss their advantages and limitations for the assessment of bone ultrastructure organization with respect to the orientation and arrangement of mineralized collagen fibrils.

The arrangement and orientation of the ultrastructure plays an important role for the mechanical properties of inhomogeneous and anisotropic materials, such as polymers, wood, or bone. However, there is a lack of techniques to spatially resolve and quantify the material's ultrastructure orientation in a macroscopic context. In this study, a new method is presented, which allows deriving the ultrastructural 3D orientation in a quantitative and spatially resolved manner. The proposed 3D scanning small-angle X-ray scattering (3D sSAXS) method was demonstrated on a thin trabecular bone specimen of a human vertebra. A micro-focus X-ray beam from a synchrotron radiation source was used to raster scan the sample for different rotation angles. Furthermore, a mathematical framework was developed, validated and employed to describe the relation between the SAXS data for the different rotation angles and the local 3D orientation and degree of orientation (DO) of the bone ultrastructure. The resulting local 3D orientation was visualized by a 3D orientation map using vector fields. Finally, by applying the proposed 3D scanning SAXS method on consecutive bone sections, a 3D map of the local orientation of a complete trabecular element could be reconstructed for the first time. The obtained 3D orientation map provided information on the bone ultrastructure organization and revealed links between trabecular bone microarchitecture and local bone ultrastructure. More specifically, we observed that trabecular bone ultrastructure is organized in orientation domains of tens of micrometers in size. In addition, it was observed that domains with a high DO were more likely to be found near the surface of the trabecular structure, and domains with lower DO (or transition zones) were located in-between the domains with high DO. The method reproducibility was validated by comparing the results obtained when scanning the sample under different sample tilt angles. 3D orientation maps such as the ones created using 3D scanning SAXS will help to quantify and understand structure–function relationships between bone ultrastructure and bone mechanics. Beyond that, the proposed method can also be used in other research fields such as material sciences, with the aim to locally determine the 3D orientation of material components.

Η P-selectin είναι μία γλυκοπρωτεϊνη της κυτταρικής επιφάνειας που εντοπίζεται στα Weiber-Polade σωμάτια των ενδοθηλιακών κυττάρων, καθώς και μέσα στα α’-κοκκία των αιμοπεταλίων. Στις θρομβογενείς και φλεγμονώδεις συνθήκες, τα επίπεδα της P-selectin του πλάσματος είναι σαφώς ηυξημένα. Σ’ αυτήν την μελέτη, έγινε μία ποιοτική ανάλυση με την μέθοδο ELISA, χρησιμοποιώντας ένα μονοκλωνικό αντίσωμα κατά της P-selectin, προκειμένου να προσδιοριστή αυτός ο δείκτης σε δείγματα αίματος τριών κλινικών ομάδων - ασθενών, που πάσχουν από αγγειακές παθήσεις. Ομάδα Ι: Εν τω βάθει φλεβοθρόμβωση των κάτω άκρων Ομάδα ΙΙ: Αρτηριακή θρομβοεμβολική νόσος των κάτω άκρων Ομάδα ΙΙΙ: Κρίσιμη ισχαιμία των κάτω άκρων Μετρήσαμε την τιμή της P-selectin του πλάσματος στις παραπάνω ομάδες, πριν και μετά 48 ώρες από την θεραπευτική αγωγή (χειρουργική ή αντιπηκτική θεραπεία). Σε σύγκριση με την ομάδα ελέγχου, όλοι αυτοί οι ασθενείς όλων των ομάδων, έδειξαν μία σαφή αύξηση των επιπέδων της P-selectin (65.95+-26.99 ng/ml vs 23+- 9 ng/ml). Tα επίπεδα της P-selectin ήσαν, επίσης, ηυξημένα σε όλες τις ομάδες των ασθενών, 48 ώρες μετά την αγωγή (67.27+- 29.03 ng/ml) (Ρ=0.625). Τα ευρήματά μας δείχνουν ότι η P-selectin του πλάσματος μπορεί να αποτελεί ένα χρήσιμο καινούριο δείκτη για τις αγγειακές παθήσεις. Η παθογένεια των παθήσεων των αγγείων, συνίσταται από το αποτέλεσμα ενός συμπλέγματος αντιδράσεων μεταξύ του ενδοθηλίου, κυκλοφορούντων λευκοκυττάρων και ενεργοποιηθέντων αιμοπεταλίων.

A flexible method to extract more high-quality information from tissue sections is critically needed for both drug discovery and clinical pathology. Here, we present micro-immunohistochemistry (μIHC), a method for staining tissue sections at the micrometre scale. Nanolitres of antibody solutions are confined over micrometre-sized areas of tissue sections using a vertical microfluidic probe (vMFP) for their incubation with primary antibodies, the key step in conventional IHC. The vMFP operates several micrometres above the tissue section, can be interactively positioned on it, and even enables the staining of individual cores of tissue microarrays with multiple antigens. μIHC using such a microfluidic probe is preservative of tissue samples and reagents, alleviates antibody cross-reactivity issues, and allows a wide range of staining conditions to be applied on a single tissue section. This method may therefore find broad use in tissue-based diagnostics and in research.

This study evaluated the relationship between severity of fatty liver and macromineral status in downer dairy cows and determined the usefulness of selected biochemical analytes for assessing prognosis. Blood and liver biopsy specimens were obtained from 36 Holstein downer cows shortly after the cows became recumbent and before they were treated. Liver tissue was examined histologically and serum activity of liver-derived enzymes and concentration of total lipids, triglycerides, bile acids, glucose, beta-hydroxybutyrate, acetoacetic acid, total bilirubin, non-esterified fatty acids (NEFA), cholesterol and macrominerals (Ca, Mg, K, Na, P) were determined. Fatty liver infiltration was severe in 44% of the cows and moderate in 44%. Serum activities of ornithine carbamoyltransferase and glutamate dehydrogenase, and NEFA/cholesterol ratio were good indicators of fatty liver. Cows with severe fatty liver had the lowest mean K values. The prognosis is guarded for downer cows with moderate and severe fatty liver and when total bilirubin concentration is high.