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Microstructural characterization and in vitro bioactivity of porous glass-ceramic scaffolds for bone regeneration by synchrotron radiation X-ray microtomography

One of the key purposes of bone tissue engineering is the development of new biomaterials that can stimulate the body's own regenerative mechanism for patient's anatomical and functional recovery. Bioactive glasses, due to their versatile properties, are excellent candidates to fabricate porous 3-D architectures for bone replacement. In this work, morphological and structural investigations are ca

μCT of ex-vivo stained mouse hearts and embryos enables a precise match between 3D virtual histology, classical histology and immunochemistry

The small size of the adult and developing mouse heart poses a great challenge for imaging in preclinical research. The aim of the study was to establish a phosphotungstic acid (PTA) ex-vivo staining approach that efficiently enhances the x-ray attenuation of soft-tissue to allow high resolution 3D visualization of mouse hearts by synchrotron radiation based μCT (SRμCT) and classical μCT. We demon

In Vivo Regenerative Properties of Coralline-Derived (Biocoral) Scaffold Grafts in Human Maxillary Defects : Demonstrative and Comparative Study with Beta-Tricalcium Phosphate and Biphasic Calcium Phosphate by Synchrotron Radiation X-Ray Microtomography

Background: In recent years, there has been interest on the fabrication of systems using particulates or block-based approach for bone tissue engineering (TE) scaffolds, possessing porous interconnected structures. In fact, these particular morphologies greatly increase the surface area for more chemical and biological reactions to take place. Purpose: This study was designed to demonstrate the un

X-Ray based Lung Function measurement - A sensitive technique to quantify lung function in allergic airway inflammation mouse models

In mice, along with the assessment of eosinophils, lung function measurements, most commonly carried out by plethysmography, are essential to monitor the course of allergic airway inflammation, to examine therapy efficacy and to correlate animal with patient data. To date, plethysmography techniques either use intubation and/or restraining of the mice and are thus invasive, or are limited in their

Morphological characterization of the human calvarium in relation to the diploic and cranial thickness utilizing X-ray computed microtomography

When attempting to establish accurate models for the human diploe, micro-scale morphological differences in the four main areas of the calvaria could also be considered. In this study, X-ray computed microtomography (μ-CT) images were analyzed in order to quantitatively characterize the micro-architecture of the human calvarium diploe. A bone specimen from each area of the skull (temporal, frontal

Phase-contrast computed tomography for quantification of structural changes in lungs of asthma mouse models of different severity

Lung imaging in mouse disease models is crucial for the assessment of the severity of airway disease but remains challenging due to the small size and the high porosity of the organ. Synchrotron inline free-propagation phase-contrast computed tomography (CT) with its intrinsic high soft-tissue contrast provides the necessary sensitivity and spatial resolution to analyse the mouse lung structure in

Quantitative evaluation of a single-distance phase-retrieval method applied on in-line phase-contrast images of a mouse lung

Propagation-based X-ray phase-contrast computed tomography (PBI) has already proven its potential in a great variety of soft-tissue-related applications including lung imaging. However, the strong edge enhancement, caused by the phase effects, often hampers image segmentation and therefore the quantitative analysis of data sets. Here, the benefits of applying single-distance phase retrieval prior

The Role of Chemotherapy in Patients with Synchronous Colorectal Liver Metastases : A Nationwide Study

Background/Objectives: There is still no consensus as to whether patients with upfront resectable synchronous colorectal liver metastases (sCRLM) should receive neoadjuvant treatment prior to liver surgery. Two randomized controlled trials have assessed the role of peri-operative chemotherapy in sCRLM; neither have shown a survival benefit in the neoadjuvant group. The aim of this population-based

Protection Against Pneumonia Induced by Vaccination with Fimbriae Subunits from Klebsiella pneumoniae

Background: Klebsiella pneumoniae infections pose a great burden worldwide, causing high morbidity and mortality, which are worsened by the increase in multidrug-resistant strains. New therapeutic/prophylactic strategies are urgently needed to overcome antibiotic resistance and reduce the health and economic impacts of diseases caused by this pathogen. Fimbriae are important virulence factors invo

Influence of palliative care policy on place of death for people with different cancer types : a nationwide’ register study

This study investigated the impact of a national palliative care policy introduced in 2013. The hypothesis was that end‑of‑life and palliative care policy shape healthcare services, which in turn influence service utilisation and ultimately place of death for people dying from cancer. The aim was to identify longitudinal trends in place of death for people with cancer in Sweden. A population‑level

Quantification of structural differences in the human calvarium diploe by means of x-ray computed microtomography image analysis : A case study

Accurate models for the human diploe have to take into account any structural differences in the four main areas of the calvaria bones. In this study the technique of Xray computed microtomography (μ-CT) along with image analysis was used in order to visualize and quantitatively analyze differences in the micro-architecture of the human calvarium diploe. A bone specimen from each area of the skull

Discovery of Cis-Regulatory Mechanisms via Non-Coding Mutations in Acute Lymphoblastic Leukemia

The non-coding genome, constituting 98% of human DNA, remains largely unexplored, yet holds potential for identifying new biomarkers and therapeutic targets in acute lymphoblastic leukemia (ALL). In this study, we conducted a systematic analysis of recurrent somatic non-coding single nucleotide variants (SNVs) in pediatric B-cell precursor (BCP) ALL. We leveraged whole genome sequencing (WGS) data

A comprehensive approach to the study of plesiosaurs: paleobiology, paleophysiology, and phylogeny

Plesiosaurs are charismatic marine reptiles of the Mesozoic Era. Life-like reconstructions of long-necked forms are typically ‘shrink-wrapped’ with a narrow, snake-like neck and a sea turtle-like body; a depiction that has changed little since the initial discovery of plesiosaurs over 200 years ago. Despite their long geological history and importance in founding paleontology as a scientific disci

Heat Operators and Isometry Groups of Cuntz–Krieger Algebras

This paper introduces heat semigroups of topological Markov chains and Cuntz–Krieger algebras by means of spectral noncommutative geometry. Using recent advances on the logarithmic Dirichlet Laplacian on Ahlfors regular metric-measure spaces, we construct spectral triples on Cuntz–Krieger algebras from singular integral operators. These spectral triples exhaust odd K-homology and for Cuntz algebra

Exciton dynamics in the light-harvesting complexes of Rhodobacter sphaeroides

We have used ≈ 40 fs pulses from a Ti:Sa laser to investigate the ultrafast energy transfer and relaxation dynamics in the LH1 and LH2 light-harvesting pigment-proteins of photosynthetic purple bacteria. Our results reveal a new feature, not earlier observed in light-harvesting pigments, ultrafast relaxation characterized by a time constant of approximately 20 fs, which we interpret as interexcito

Directed picosecond excitation transport in purple photosynthetic bacteria

Picosecond spectrally resolved fluorescent measurements together with the coupled kinetic rate equation model simulations of the data have been employed to determine the rates and pathways of heterogeneous excitation transport in the membranes of photosynthetic bacteria Rhodobacter sphaeroides and Chromatium minutissimum. Excitation transport from bacteriochlorophyll molecules B800 to B850, belong

Fluorescence and absorption spectroscopy of the weakly fluorescent chlorophyll a in cytochrome b6f of Synechocystis PCC6803

A spectroscopic characterization of the chlorophyll a (Chl) molecule in the monomeric cytochrome b6f complex (Cytb6f) isolated from the cyanobacterium Synechocystis PCC6803 is presented. The fluorescence lifetime and quantum yield have been determined, and it is shown that Chl in Cytb6f has an excited-state lifetime that is 20 times smaller than that of Chl in methanol. This shortening of the Chl

Electron-phonon coupling in the B820 subunit form of LH1 studied by temperature dependence of optical spectra

The temperature dependence of absorption and selectively excited fluorescence spectra of B820 subunit of the bacterial light-harvesting antenna is modelled by using the impurity center theory ofoptical spectra. In order toget acceptable agreement between theory and experiment, we suggest that due to the dimeric nature of B820, the electronic transition is weakly coupled to a rather broad distribut

Picosecond fluorescence of simple photosynthetic membranes : Evidence of spectral inhomogeneity and directed energy transfer

The picosecond time-domain singlet excitation transfer and trapping kinetics in photosynthetic membranes in case of low excitation intensities is studied by numerical integration of the appropriate master equation. The essential features of our two-dimensional-lattice random walk model are spectral heterogeneity of the light-harvesting antenna, inclusion of temperature effects, nonabsolute excitat