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[EN] The calculation of overlaps between many-electron wave functions at different nuclear geometries during nonadiabatic dynamics simulations requires the evaluation of a large number of determinants of matrices that differ only in a few rows/columns. While this calculation is fast for small systems, its cost grows faster than the alternative electronic structure calculation used to obtain the wave functions. For wave functions that can be written as a CIS expansion, all determinants can be computed using the set of level-2 minors of the reference matrix. However, this is still a costly computation for large systems. In this paper, we provide an algorithm for efficiently calculating all level-2 minors of a matrix by re-utilizing and updating the LU factorization for the determinants of the minors. This approach results in a parallel version of the algorithm that is up to an order of magnitude faster then the current best parallel implementation. The algorithm thus allows the computation of exact wave function overlaps for relatively large systems, with a high density of states, at virtually no cost compared with the electronic structure calculations. Furthermore, the new algorithm opens the path to further investigations in efficient computing of the exact wave function overlaps for complex wave functions such as MR-CIS and MR-CISD. Program summary Program Title: CIS Overlap Licensing provisions: MIT Programming language: FORTRAN 2008, C Nature of problem: Calculation of overlaps between CIS type wave functions at different nuclear geometries during nonadiabatic dynamics simulation requires calculating a large number of connected determinants and scales with the seventh power of the size of the system being studied. Without additional approximations, for large systems this computation becomes more costly than the electronic structure calculation used to obtain the wave functions. Solution method: All of the determinants required for a CIS wave function overlap calc

[EN] The calculation of overlaps between many-electron wave functions at different nuclear geometries during nonadiabatic dynamics simulations requires the evaluation of a large number of determinants of matrices that differ only in a few rows/columns. While this calculation is fast for small systems, its cost grows faster than the alternative electronic structure calculation used to obtain the wave functions. For wave functions that can be written as a CIS expansion, all determinants can be computed using the set of level-2 minors of the reference matrix. However, this is still a costly computation for large systems. In this paper, we provide an algorithm for efficiently calculating all level-2 minors of a matrix by re-utilizing and updating the LU factorization for the determinants of the minors. This approach results in a parallel version of the algorithm that is up to an order of magnitude faster then the current best parallel implementation. The algorithm thus allows the computation of exact wave function overlaps for relatively large systems, with a high density of states, at virtually no cost compared with the electronic structure calculations. Furthermore, the new algorithm opens the path to further investigations in efficient computing of the exact wave function overlaps for complex wave functions such as MR-CIS and MR-CISD. Program summary Program Title: CIS Overlap Licensing provisions: MIT Programming language: FORTRAN 2008, C Nature of problem: Calculation of overlaps between CIS type wave functions at different nuclear geometries during nonadiabatic dynamics simulation requires calculating a large number of connected determinants and scales with the seventh power of the size of the system being studied. Without additional approximations, for large systems this computation becomes more costly than the electronic structure calculation used to obtain the wave functions. Solution method: All of the determinants required for a CIS wave function overlap calc

[EN] Bioactive synthetic hydrogels have emerged as promising materials because they can provide molecularly tailored biofunctions and adjustable mechanical properties. To mimic the mineralogical and organic components of the natural bone, hydroxyapatite and a tyramine conjugate of gelatine were combined in this study. The effect of various amounts of in situ synthesized hydroxyapatite in gelatine-tyramine on the morphology and physical properties of injectable hydrogels was investigated. Mineralogical identification confirmed successful precipitation of in situ formed hydrox yapatite. Better distribution of hydroxyapatite crystal agglomerates within modified gelatine was found at 5 % of hydroxyapatite, which could be responsible for increased storage modulus with respect to pure gelatine hydrogel. Prepared composite hydrogels are non-toxic and support the proliferation of Hek293 cells.

[EN] An intelligent virtual environment simulates a physical world inhabited by autonomous intelligent entities. Multi-agent systems have been usually employed to design systems of this kind. One of the key aspects in the design of intelligent virtual environments is the use of appropriate ontologies which offer a richer and more expressive representation of knowledge. In this sense, this paper proposes an ontology comprising concepts for modelling intelligent virtual environments enhanced with concepts for describing agent-based organisational features. This new ontology, called MAMbO5, is used as an input of the JaCalIVE framework, which is a toolkit for the design and implementation of agent-based intelligent virtual environments.

[EN] Bioactive synthetic hydrogels have emerged as promising materials because they can provide molecularly tailored biofunctions and adjustable mechanical properties. To mimic the mineralogical and organic components of the natural bone, hydroxyapatite and a tyramine conjugate of gelatine were combined in this study. The effect of various amounts of in situ synthesized hydroxyapatite in gelatine-tyramine on the morphology and physical properties of injectable hydrogels was investigated. Mineralogical identification confirmed successful precipitation of in situ formed hydrox yapatite. Better distribution of hydroxyapatite crystal agglomerates within modified gelatine was found at 5 % of hydroxyapatite, which could be responsible for increased storage modulus with respect to pure gelatine hydrogel. Prepared composite hydrogels are non-toxic and support the proliferation of Hek293 cells.

[EN] Injectable hydrogels have emerged as promising biomaterials for tissue engineering applications. The goal of this study was to evaluate the potential of a pH-responsive chitosan-hydroxyapatite hydrogel to be used as a three-dimensional support for encapsulated mesenchymal stem cells (MSCs) osteogenic differentiation. In vitro enzymatic degradation of the hydrogel, during 28 days of incubation, in simulated physiological condiditons, was characterized by swelling measurements, molecular weight determination and SEM analysis of hydrogel microstructure. Osteogenic differentiation of encapsulated MSCs was confirmed by osteogenic Runx2, collagen type I and osteocalcin immunostaining and alkaline phosphatase quantification. The deposition of late osteogenic markers (calcium phosphates) detected by Alizarin red and von Kossa staining indicated an extracellular matrix mineralization.

[EN] Injectable hydrogels have emerged as promising biomaterials for tissue engineering applications. The goal of this study was to evaluate the potential of a pH-responsive chitosan-hydroxyapatite hydrogel to be used as a three-dimensional support for encapsulated mesenchymal stem cells (MSCs) osteogenic differentiation. In vitro enzymatic degradation of the hydrogel, during 28 days of incubation, in simulated physiological condiditons, was characterized by swelling measurements, molecular weight determination and SEM analysis of hydrogel microstructure. Osteogenic differentiation of encapsulated MSCs was confirmed by osteogenic Runx2, collagen type I and osteocalcin immunostaining and alkaline phosphatase quantification. The deposition of late osteogenic markers (calcium phosphates) detected by Alizarin red and von Kossa staining indicated an extracellular matrix mineralization.

[EN] Injectable hydrogels have emerged as promising biomaterials for tissue engineering applications. The goal of this study was to evaluate the potential of a pH-responsive chitosan-hydroxyapatite hydrogel to be used as a three-dimensional support for encapsulated mesenchymal stem cells (MSCs) osteogenic differentiation. In vitro enzymatic degradation of the hydrogel, during 28 days of incubation, in simulated physiological condiditons, was characterized by swelling measurements, molecular weight determination and SEM analysis of hydrogel microstructure. Osteogenic differentiation of encapsulated MSCs was confirmed by osteogenic Runx2, collagen type I and osteocalcin immunostaining and alkaline phosphatase quantification. The deposition of late osteogenic markers (calcium phosphates) detected by Alizarin red and von Kossa staining indicated an extracellular matrix mineralization.

[EN] The effects of mitogenome variation on economically important traits have been reported in a number of domestic animal species. In this study, the first of its kind on rabbits, we have performed the estimation of the contribution of cytoplasmic and D-loop mitochondrial DNA (mtDNA) sequence effects on the litter size and carcass traits in three Pannon rabbit breeds (Pannon Ka, Pannon Large and Pannon White). The observed effects of both estimates, coming from cytoplasmic or D-loop mtDNA variation, were negligible. The most likely explanation for the results obtained is the lack of mitogenome polymorphism in all three populations, as suggested from the analysis performed on the D-loop mtDNA sequence, here assigned to the two most frequent rabbit haplotypes. The extent of potential benefits of the introduction, or alteration, of mitogenome variation in rabbit breeding remains an open question for future research.

[EN] The effects of mitogenome variation on economically important traits have been reported in a number of domestic animal species. In this study, the first of its kind on rabbits, we have performed the estimation of the contribution of cytoplasmic and D-loop mitochondrial DNA (mtDNA) sequence effects on the litter size and carcass traits in three Pannon rabbit breeds (Pannon Ka, Pannon Large and Pannon White). The observed effects of both estimates, coming from cytoplasmic or D-loop mtDNA variation, were negligible. The most likely explanation for the results obtained is the lack of mitogenome polymorphism in all three populations, as suggested from the analysis performed on the D-loop mtDNA sequence, here assigned to the two most frequent rabbit haplotypes. The extent of potential benefits of the introduction, or alteration, of mitogenome variation in rabbit breeding remains an open question for future research.

[EN] The effects of mitogenome variation on economically important traits have been reported in a number of domestic animal species. In this study, the first of its kind on rabbits, we have performed the estimation of the contribution of cytoplasmic and D-loop mitochondrial DNA (mtDNA) sequence effects on the litter size and carcass traits in three Pannon rabbit breeds (Pannon Ka, Pannon Large and Pannon White). The observed effects of both estimates, coming from cytoplasmic or D-loop mtDNA variation, were negligible. The most likely explanation for the results obtained is the lack of mitogenome polymorphism in all three populations, as suggested from the analysis performed on the D-loop mtDNA sequence, here assigned to the two most frequent rabbit haplotypes. The extent of potential benefits of the introduction, or alteration, of mitogenome variation in rabbit breeding remains an open question for future research.

[EN] The effects of mitogenome variation on economically important traits have been reported in a number of domestic animal species. In this study, the first of its kind on rabbits, we have performed the estimation of the contribution of cytoplasmic and D-loop mitochondrial DNA (mtDNA) sequence effects on the litter size and carcass traits in three Pannon rabbit breeds (Pannon Ka, Pannon Large and Pannon White). The observed effects of both estimates, coming from cytoplasmic or D-loop mtDNA variation, were negligible. The most likely explanation for the results obtained is the lack of mitogenome polymorphism in all three populations, as suggested from the analysis performed on the D-loop mtDNA sequence, here assigned to the two most frequent rabbit haplotypes. The extent of potential benefits of the introduction, or alteration, of mitogenome variation in rabbit breeding remains an open question for future research.

[EN] The effects of mitogenome variation on economically important traits have been reported in a number of domestic animal species. In this study, the first of its kind on rabbits, we have performed the estimation of the contribution of cytoplasmic and D-loop mitochondrial DNA (mtDNA) sequence effects on the litter size and carcass traits in three Pannon rabbit breeds (Pannon Ka, Pannon Large and Pannon White). The observed effects of both estimates, coming from cytoplasmic or D-loop mtDNA variation, were negligible. The most likely explanation for the results obtained is the lack of mitogenome polymorphism in all three populations, as suggested from the analysis performed on the D-loop mtDNA sequence, here assigned to the two most frequent rabbit haplotypes. The extent of potential benefits of the introduction, or alteration, of mitogenome variation in rabbit breeding remains an open question for future research.

[EN] The effects of mitogenome variation on economically important traits have been reported in a number of domestic animal species. In this study, the first of its kind on rabbits, we have performed the estimation of the contribution of cytoplasmic and D-loop mitochondrial DNA (mtDNA) sequence effects on the litter size and carcass traits in three Pannon rabbit breeds (Pannon Ka, Pannon Large and Pannon White). The observed effects of both estimates, coming from cytoplasmic or D-loop mtDNA variation, were negligible. The most likely explanation for the results obtained is the lack of mitogenome polymorphism in all three populations, as suggested from the analysis performed on the D-loop mtDNA sequence, here assigned to the two most frequent rabbit haplotypes. The extent of potential benefits of the introduction, or alteration, of mitogenome variation in rabbit breeding remains an open question for future research.

[EN] The development of bioactive injectable system as cell carrier with minimal impact on viability of encapsulated cells represents a great challenge. In the present work, we propose a new pH-responsive chitosan-hydroxyapatite-based hydrogel with sodium bicarbonate (NaHCO3) as the gelling agent. The in situ synthesis of hydroxyapatite phase has resulted in stable composite suspension and final homogeneous hydrogel. The application of sodium bicarbonate has allowed non-cytotoxic fast gelation of chitosan-hydroxyapatite within 4min, and without excess of sodium ions concentration. Rheological properties of crosslinked hydrogel have demonstrated possible behaviour as 'strong physical hydro gel'. The live dead staining has confirmed good viability and dispersion, as well as proliferation of encapsulated cells by the culture time. Presented preliminary results show good potential of chitosanhydroxyapatite/NaHCO3 as a cell carrier, whose impact on the cell differentiation need to be confirmed by encapsulation of other cell phenotypes.

[EN] The development of bioactive injectable system as cell carrier with minimal impact on viability of encapsulated cells represents a great challenge. In the present work, we propose a new pH-responsive chitosan-hydroxyapatite-based hydrogel with sodium bicarbonate (NaHCO3) as the gelling agent. The in situ synthesis of hydroxyapatite phase has resulted in stable composite suspension and final homogeneous hydrogel. The application of sodium bicarbonate has allowed non-cytotoxic fast gelation of chitosan-hydroxyapatite within 4min, and without excess of sodium ions concentration. Rheological properties of crosslinked hydrogel have demonstrated possible behaviour as 'strong physical hydro gel'. The live dead staining has confirmed good viability and dispersion, as well as proliferation of encapsulated cells by the culture time. Presented preliminary results show good potential of chitosanhydroxyapatite/NaHCO3 as a cell carrier, whose impact on the cell differentiation need to be confirmed by encapsulation of other cell phenotypes.

[EN] The extensive need for hard tissue substituent greatly motivates development of suitable allogeneic grafts for therapeutic recreation. Different calcium phosphate phases have been accepted as scaffold's components with positive influence on osteoinduction and differentiation of human mesenchymal stem cells, in terms of their higher fraction within the graft. Nevertheless, the creation of unlimited nutrients diffusion through newly formed grafts is of great importance. The media flow accomplished by perfusion forces can provide physicochemical, and also, biomechanical stimuli for three-dimensional bone-construct growth. In the present study, the influence of a different scaffold's composition on the human mesenchymal stem cells (hMSCs) differentiation performed in a U-CUP bioreactor under perfusion conditioning was investigated. The histological and immunohistochemical analysis of cultured bony tissues, and the evaluation of osteogenic genes' expression indicate that the lower fraction of in situ formed hydroxyapatite in the range of 10-30% within chitosan scaffold could be preferable for bone-construct development.

[EN] The extensive need for hard tissue substituent greatly motivates development of suitable allogeneic grafts for therapeutic recreation. Different calcium phosphate phases have been accepted as scaffold's components with positive influence on osteoinduction and differentiation of human mesenchymal stem cells, in terms of their higher fraction within the graft. Nevertheless, the creation of unlimited nutrients diffusion through newly formed grafts is of great importance. The media flow accomplished by perfusion forces can provide physicochemical, and also, biomechanical stimuli for three-dimensional bone-construct growth. In the present study, the influence of a different scaffold's composition on the human mesenchymal stem cells (hMSCs) differentiation performed in a U-CUP bioreactor under perfusion conditioning was investigated. The histological and immunohistochemical analysis of cultured bony tissues, and the evaluation of osteogenic genes' expression indicate that the lower fraction of in situ formed hydroxyapatite in the range of 10-30% within chitosan scaffold could be preferable for bone-construct development.

[EN] Poor mechanical performance of porous chitosan-hydroxyapatite systems is the main limitation in bone tissue engineering. If we merge good mechanical performance of poly(lactic acid) construct with osteoinductive and bioresorbable properties of chitosan-hydroxyapatite porous hydrogel, we can obtain a material that meets necessary requirement for bone tissue substituent. With this in mind, we propose the combination of 3D printing technique and the thermally-induced phase separation method for simultaneous modification of biological properties of poly(lactic acid) and load-bearing properties of chitosan-hydroxyapatite porous hydrogel. 3D printed poly(lactic acid), PLA, construct has been used as a mechanical support with very large pore diameter of 960 +/- 50 mu m allowing enough free space (similar to 60% of porosity) to form porous composite hydrogel by freeze gelation. In situ formation of hydroxyapatite within chitosan hydrogel has ensured higher human mesenchymal stem cell osteogenesis during 21 days of culture. Positive modification of poly(lactic acid) has been simultaneously utilized to improve the compressive strength of composite hydrogel which has been confirmed by Young's modulus ranging from lower values reported for cancellous bone in dry state. Considering positive osteogenic signal accompanied with suitable mechanical properties, our scaffolds have shown good potential as bone tissue substituent. (C) 2016 Elsevier Ltd. All rights reserved.

[EN] Poor mechanical performance of porous chitosan-hydroxyapatite systems is the main limitation in bone tissue engineering. If we merge good mechanical performance of poly(lactic acid) construct with osteoinductive and bioresorbable properties of chitosan-hydroxyapatite porous hydrogel, we can obtain a material that meets necessary requirement for bone tissue substituent. With this in mind, we propose the combination of 3D printing technique and the thermally-induced phase separation method for simultaneous modification of biological properties of poly(lactic acid) and load-bearing properties of chitosan-hydroxyapatite porous hydrogel. 3D printed poly(lactic acid), PLA, construct has been used as a mechanical support with very large pore diameter of 960 +/- 50 mu m allowing enough free space (similar to 60% of porosity) to form porous composite hydrogel by freeze gelation. In situ formation of hydroxyapatite within chitosan hydrogel has ensured higher human mesenchymal stem cell osteogenesis during 21 days of culture. Positive modification of poly(lactic acid) has been simultaneously utilized to improve the compressive strength of composite hydrogel which has been confirmed by Young's modulus ranging from lower values reported for cancellous bone in dry state. Considering positive osteogenic signal accompanied with suitable mechanical properties, our scaffolds have shown good potential as bone tissue substituent. (C) 2016 Elsevier Ltd. All rights reserved.

Highly porous chitosan/hydroxyapatite composite structures with different weight ratios (100/0; 90/10; 80/20; 70/30; 60/40; 50/50; 40/60) have been prepared by precipitation method and freeze-gelation technique using calcite, urea phosphate and chitosan as starting materials. The composition of prepared composite scaffolds was characterized by X-ray diffraction analysis and Fourier transformed infrared spectroscopy, while morphology of scaffolds was imaged by scanning electron microscopy. Mercury intrusion porosimetry measurements of prepared scaffolds have shown different porosity and microstructure regarding to the HA content, along with SEM observations of scaffolds after being immersed in physiological medium. The results of swelling capacity and compressive strength measured in Dulbecco’s phosphate buffer saline (DPBS) have shown higher values for composite scaffolds with lower in situ HA content. Viability, proliferation and differentiation of MC3T3-E1 cells seeded on different scaffolds have been evaluated by live dead assay and confocal scan microscopy. Our results suggest that the increase of HA content enhance osteoblast differentiation confirming osteogenic properties of highly porous CS/HA scaffolds for tissue engineering applications in bone repair.