Hydrothermally extracted nanohydroxyapatite from bovine bone as bioceramic and biofiller in bionanocomposite

Bones have an extraordinary capacity to restore and regenerate in case of minor injury. However, major injuries need orthopedic surgeries that required bone implant biomaterials. In this study, n-HAP powder was extracted from bovine bone by hydrothermal and calcined at different calcination temperatures (600-1100°C) without the use of solvents. The n-HAP powders produced were used to fabricate two types of biomaterials (HAP bioceramics and PLA/n-HAP bionanocomposite). The raw-HAP and calcined n-HAP powder samples were compacted into green bodies and were sintered at various temperatures (1000-1400°C) to produce HAP bioceramics. The best calcined n-HAP was mixed with PLA by melt mixing and injection moulding to fabricate PLA/n-HAP bionanocomposite. Characterizations of the n-HAP powder, n-HAP bioceramics and PLA/n-HAP bionanocomposite samples were done by Thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transforms infrared (FTIR), Field emission scanning electron microscopy (FESEM), Energy-dispersive x-ray spectroscopy (EDX), X-ray fluorescence (XRF) spectroscopy, universal testing machine (UTM) and melt flow index (MFI) analyses. TGA data revealed that n-HAP was thermally stable at 1300ºC. The extracted n-HAP powder was highly crystalline and crystallite size was in the range of 10-83 nm as confirmed by XRD. Density and hardness of the n-HAP bioceramics increased as sintering temperature increased and showing maximum values at a temperature of 1400°C. The results of PLA/n-HAP bionanocomposite revealed that the higher n-HAP loaded (at 5wt%), the lower the tensile strength of bionanocomposite due to poor interfacial adhesion. The interfacial adhesion was improved by loading of 1.0 wt% maleic anhydride (MAH) as a compatibilizer. The biocompatibility of bionanocomposite was evaluated in simulated body fluids (SBF). The results showed that apatite layers were grown on the surfaces of both biomaterials. Therefore, both biomaterials formulated shall be promising medical biomaterials for orthopedic applications

Toward epistemic empowerment of indigenous youth

Using a grounded-theory approach this study critically examines a development education program of an NGO, the Institute for Development Studies and Practices (IDSP) in Balochistan, Pakistan. IDSP’s Academic Development Program (ADP) is influenced by critical pedagogy, and post-colonial and post-modern studies. IDSP targets out-of-school youth and young adults of marginalized communities who are politically and socially conscious and looking for openings, inspirations, and direction to solve the issues confronting their communities. In addition to grounded theory itself, theoretical perspectives used in this study include: postmodern critical theory, transformative learning theory, critical pedagogy, and post-colonial studies. Data sources include ADP-related documents and open-ended interviews with four IDSP administrators, three teachers, six female students, and eight male students. I used convenience, purposive, and theoretical sampling techniques to select my research participants. To analyze my data, I utilized two major analytical tools, “content analysis” and “constant comparison” throughout the research process. The research findings reveal that ADP has developed critical consciousness in marginalized youth, improved their cultural self-esteem, enabled them to reclaim elements of their history and self-worth, and developed in them a sense of ownership and responsibility for their own knowledge. It has given them civic courage to raise their voice against exploitation, nepotism, and corruption and it has motivated them to connect with the world beyond their local region. Finally, it has enhanced their professional development capabilities. This study traces a model of epistemic empowerment of indigenous youth across eight categories: (i) fostering critical imagination and analytical skills, (ii) strengthening connections with local culture, (iii) mastering professional skills, (iv) initiating praxis, (v) breaking the culture of silence, (vi) embracing ethically and socially responsible knowledge, (vii) encountering resistance in applying emancipatory ideas, and (viii) becoming “universal.” Case studies, particularly single case studies, are not generalizable in any sense to different contexts and time. However, the IDSP experience chronicled in this study through the eyes of direct stakeholders offers potential lessons for those who find themselves similarly situated in potentially comparable circumstances

Multiple Cultures, Multiple Literacies, and Collective Agencies: Chinese and Pakistani Immigrants’ Perceptions of Family Literacy Support

Challenging the deficit view of immigrant families’ roles in family literacy support, this study is situated in the multiliteracies theoretical framework, which celebrates marginalized, yet diverse, literacy practices in immigrant families. This study used semi-structured interviews and focus group discussions to map diverse family literacy practices in Chinese and Pakistani families. It explores whether and how available educational institutions have been inclusive of immigrant families’ multiple cultures and multiple literacies. Adopting a bottom-up advocacy approach, this study also invites Chinese and Pakistani families to envision family literacy programs by themselves. It brings to light immigrant families’ potential collective agencies in effecting changes to enable more inclusive family literacy programs in the culturally and linguistically diverse context of Canada. Cet article défit la vision négative du rôle des familles d’immigrés dans le support de la littératie familiale. L’étude se situe dans le cadre conceptuel des multi-littératies qui supportent des pratiques de littératie marginalisées mais néanmoins très diverses dans des familles d’immigrés. La méthodologie d’entrevues semi structurées et de groupes de discussions utilisée a permis de décrire les différentes pratiques de littératie adoptées dans des familles chinoises et pakistanaises. Cette étude cherche également à explorer si les institutions éducatives ont pris en compte les différentes cultures et littératies des familles, et dans le cas positif, comment cette prise en compte s’est effectuée. L’analyse vise aussi à inviter les familles chinoises et pakistanaises à créer leurs propres programmes de littératie en utilisant une approche de soutien ascendant. Les résultats montrent un potentiel collectif d’agentivité qui pourrait engendrer la création de plus de programmes de littératie familiaux dans le contexte multiculturel et multilinguistique du Canada

Extraction of biological apatite from cow bone at different calcination temperatures: a comparative study

The purpose of this study is to extract natural hydroxyapatite (HAP) from cow bone. The hydrothermal method followed by calcination treatment at different temperatures is used in this current research. Cow bone has the potential for producing hydroxyapatite, a chief component present in bone and teeth of vertebrates. HAP is an excellent material used in bone restoration and tissue regeneration. Characterizations of the cow bone natural HAP powder were done by X-ray diffraction (XRD) and Thermogravimetric analysis (TGA). TGA data revealed that biological apatite is thermally stable at 1100ºC. XRD data showed that the extracted HAP is, highly crystalline and hexagonal crystal structure having a crystallite size in the range of 10-83 nm. The extracted HAP material is found to be thermally stable up to 1300ºC

FTIR and XRD evaluation of magnesium doped hydroxyapatitesodium alginate powder by precipitation method

Composites material were developed to acquire the desired material properties for biomedical applications in the recovery of defect bone by using Mg-doped HA/SA. Hydroxyapatite (HA) is the major constituent and essential component in bone and teeth. The stability of Mg-doped HA/SA is influenced by starting precursor powders, preparation condition and method of preparing the samples for implant materials. The precipitation method was employed to prepare Mg-doped HA/SA powders by varying the composition of Mg at temperature 1300°C. The influence of Mg-doped HA/SA on phase composition, chemical structure and a functional group at various weight percentages (0.5wt%-1.5wt %) were accomplished through X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) analyses. Based on the XRD and FTIR analyses, there is the presence of different peaks intensity and adsorption bands which indicates the shifted of peaks due to the doping process and a chemical interaction were observed between the inorganic and organic phase. Furthermore, the transformation of β-TCP due to increase in sintering temperatures are caused by the presence of magnesium ions. The OHstretching bands of HA/SA are traced by FTIR that identified the decomposition of Mg-doped HA/SA

Natural Hydroxyapatite Extracted From Bovine Bone

The aim of this study is to extract natural hydroxyapatite (HAP) from bovine bone. Hydrothermal method followed by calcination treatment at different temperatures is used in this current research. Bovine bone has potential for producing hydroxyapatite, a chief component present in bone and teeth of vertebrates. HAP is an excellent material used in bone restoration and tissue regeneration. Characterizations of the bovine bone natural HAP powder were done by scanning electron microscopy (SEM), Fourier transforms infrared (FTIR) and energy dispersive x-ray (EDX) spectroscopy. The FTIR result confirms the presence of phosphate (PO4-3), hydroxyl (OH)- and carbonate (CO3-2) groups in the powder. SEM displays the surface morphology whereas EDX provides calcium (Ca) to phosphorous (P) ratio in the HAP samples. The results of the EDX analysis indicate that the Ca/P ratio of HAP varies from 1.67 to 1.83. The extracted HAP material is found to be thermally stable up to 1100ºC

Fabrication and Characterization of Direct Recycled Al-Cu-Cullet Metal Composite

A composite is any material which consist of two or more components of different phases and with different and superior than those of any of the original materials. In the present work, Aluminium (Al) composites were fabricated from direct recycle of Aluminium scrap from door and window frames, used copper (Cu) wires and cullet powder (CP) using stir casting method. The processing parameter of these composites were only varied in their holding time during casting process. The composites and the matrix alloy were analysed for mechanical properties as well as for their chemical composition. The mechanical property, hardness, of the composites in addition to some physical properties such as density was found to have enhanced in the product. The fabricated composites were analysed using energy dispersive x-ray spectroscopy (EDX) and results have shown ascertained that the chemical composition of the product comprising all the components while X-ray Diffraction (XRD), results confirmed qualitatively, the chemical structures of the elemental components. The tests results indicated that the Al-Cu-CP metal matrix composites (MMCs) had shown higher degree of hardness along with density than the unreinforced matrix

Mitochondrial plasticity supports proliferative outgrowth and invasion of ovarian cancer spheroids during adhesion

BackgroundOvarian cancer cells aggregate during or after exfoliation from the primary tumor to form threedimensional spheroids. Spheroid formation provides a survival advantage during peritoneal dissemination in nutrient and oxygen-depleted conditions which is accompanied by a suppressed metabolic phenotype and fragmented mitochondria. Upon arrival to their metastatic sites, spheroids adhere to peritoneal organs and transition to a more epithelial phenotype to support outgrowth and invasion. In this study, we investigated the plasticity of mitochondrial morphology, dynamics, and function upon adhesion.MethodsUsing our slow-developing (MOSE-L) and fast-developing (MOSE-LTICv) ovarian cancer models, we mimicked adhesion and reoxygenation conditions by plating the spheroids onto tissue culture dishes and changing culture conditions from hypoxia and low glucose to normoxia with high glucose levels after adhesion. We used Western Blot, microscopy and Seahorse analyses to determine the plasticity of mitochondrial morphology and functions upon adhesion, and the impact on proliferation and invasion capacities.ResultsIndependent of culture conditions, all spheroids adhered to and began to grow onto the culture plates. While the bulk of the spheroid was unresponsive, the mitochondrial morphology in the outgrowing cells was indistinguishable from cells growing in monolayers, indicating that mitochondrial fragmentation in spheroids was indeed reversible. This was accompanied by an increase in regulators of mitobiogenesis, PGC1a, mitochondrial mass, and respiration. Reoxygenation increased migration and invasion in both cell types but only the MOSE-L responded with increased proliferation to reoxygenation. The highly aggressive phenotype of the MOSE-LTICv was characterized by a relative independence of oxygen and the preservation of higher levels of proliferation, migration and invasion even in limiting culture conditions but a higher reliance on mitophagy. Further, the outgrowth in these aggressive cells relies mostly on proliferation while the MOSE-L cells both utilize proliferation and migration to achieve outgrowth. Suppression of proliferation with cycloheximide impeded aggregation, reduced outgrowth and invasion via repression of MMP2 expression and the flattening of the spheroids.DiscussionOur studies indicate that the fragmentation of the mitochondria is reversible upon adhesion. The identification of regulatory signaling molecules and pathways of these key phenotypic alterations that occur during primary adhesion and invasion is critical for the identification of druggable targets for therapeutic intervention to prevent aggressive metastatic disease

Fabrication and Characterization of Nanocrystalline Hydroxyapatite Extracted from Bovine Bone at Different Calcination Temperatures

Hydroxyapatite (HAP) is a calcium phosphate based bioceramics and a basic mineral component of teeth and bones of vertebrates. Its chemical and structural features are analogous to the inorganic components of bone. The present work focuses on the fabrication and characterizations of nanocrystalline HAP extracted from bovine bone at different calcination temperatures (600, 800, and 1000°C) without the use of chemicals/solvents. Therefore, it is a green technology. The characterizations of the extracted n-HAP were carried out by X-ray diffraction (XRD), Fourier transforms infrared (FTIR) and Field emission scanning electron microscopy (FESEM)  The FTIR results confirmed the presence of phosphate PO4-3, hydroxyl OH-1 and carbonate CO3-2 groups in the n-HAP powder. FESEM observation confirmed the hexagonal rod like structure. XRD analysis revealed that extracted n-HAP has a hexagonal crystal structure and crystallite size was in the range of 10.48-84.08 nm. Crystallinity degree and crystallite size gradually increased with the intensification of calcination temperature from 600 °C -1000 °C.&nbsp

Fabrication and Characterization of Nanocrystalline Hydroxyapatite Extracted from Bovine Bone at Different Calcination Temperatures

Hydroxyapatite (HAP) is a calcium phosphate based bioceramics and a basic mineral component of teeth and bones of vertebrates. Its chemical and structural features are analogous to the inorganic components of bone. The present work focuses on the fabrication and characterizations of nanocrystalline HAP extracted from bovine bone at different calcination temperatures (600, 800, and 1000°C) without the use of chemicals/solvents. Therefore, it is a green technology. The characterizations of the extracted n-HAP were carried out by X-ray diffraction (XRD), Fourier transforms infrared (FTIR) and Field emission scanning electron microscopy (FESEM)  The FTIR results confirmed the presence of phosphate PO4-3, hydroxyl OH-1 and carbonate CO3-2 groups in the n-HAP powder. FESEM observation confirmed the hexagonal rod like structure. XRD analysis revealed that extracted n-HAP has a hexagonal crystal structure and crystallite size was in the range of 10.48-84.08 nm. Crystallinity degree and crystallite size gradually increased with the intensification of calcination temperature from 600 °C -1000 °C.&nbsp