inorganic mineral
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Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6133
Author(s):  
Abhishek Indurkar ◽  
Rajan Choudhary ◽  
Kristaps Rubenis ◽  
Janis Locs

Calcium phosphate (CaP) biomaterials are extensively used to reconstruct bone defects. They resemble a chemical similarity to the inorganic mineral present in bones. Thus, they are termed as the key players in bone regeneration. Sintering is a heat treatment process applied to CaP powder compact or fabricated porous material to impart strength and integrity. Conventional sintering is the simplest sintering technique, but the processing of CaPs at a high temperature for a long time usually leads to the formation of secondary phases due to their thermal instability. Furthermore, it results in excessive grain growth that obstructs the densification process, limiting the application of CaP’s ceramics in bone regeneration. This review focuses on advanced sintering techniques used for the densification of CaPs. These techniques utilize the synergy of temperature with one or more parameters such as external pressure, electromagnetic radiation, electric current, or the incorporation of transient liquid that boosts the mass transfer while lowering the sintering temperature and time.


2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 136-136
Author(s):  
Tom W Geary ◽  
Carl R Dahlen ◽  
Abigail L Zezeski

Abstract The greatest effects of nutrition on bull fertility occur by providing a relatively high plane of nutrition during calfhood when the seminiferous epithelium of the testes is developing. A high plane of nutrition from 5 to 25 weeks of age results in greater circulating gonadotropin concentrations, greater testicular volume, and greater sperm production at maturity. At this age, diet can be manipulated by creep feeding bull calves with both protein and energy supplements which could accelerate puberty and increase sperm production. Increased rate of gain in bull calves post-weaning can accelerate puberty a few weeks, but excess post-weaning gain and fat buildup in the neck of the scrotum can have detrimental effects on fertility. Considerable emphasis has been placed on specific micronutrient (especially minerals) effects on peripubertal bull fertility. Trace mineral supplementation is believed to be critical for optimal fertility and both copper (Cu) and zinc (Zn) supplementation have influenced male fertility in other species. However, there are no guidelines for recommended levels of these minerals to ensure fertility. Providing organic or complexed compared to inorganic mineral to peripubertal bulls have increased liver concentrations of mineral and in some cases, have accelerated puberty, but enhanced fertility-associated measures have not been realized. Because both Cu and Zn are present in the ejaculate, mineral needs during the breeding season may differ from the off-season. During the breeding season, bulls can lose 10 to 20% of their weight and need to re-gain this weight before the next breeding season. Divergent planes of nutrition provided to mature bulls during the off-season revealed enhanced sperm energy and stress-fighting potential with decreasing plane of nutrition. Specific mineral supplementation during the off-season in mature bulls provides no beneficial effect on fertility-associated measures. In summary, significant effects of nutrition post-weaning on bull fertility-associated measures have not been realized.


Author(s):  
Mithuna M

Abstract: Soilless substrates have many advantages over soil based system as they provide optimal conditions for plant growth when compared to soil-based agricultural practices. Different substrates are currently being used as support to the root system of plant. Substrates can be organic such as peat, bark, bagasse, sawdust, rice hulls, wood chips, etc. They can be inorganic mineral based such as sand, gravel, perlite, and stone wool slab. As the second phase of an earlier work by one of the authors on softboard as a novel wood fibre-based substrate for hydroponic systems, the present study was carried out to explore the effects of biochar amendment to wood pulps (or pulp wastes generated from fiberboard factories), on seed germination and seedling growth of Green gram (Phaseolus aureus) crop. The study also included a comparison of seedling growth in hardwood pulp and softwood pulp and to select the most suitable one for container cultivations. Keywords: Sawdust, biochar, wood pulp, green gram, container cultivation


2021 ◽  
Vol 3 (1) ◽  
pp. 8-11
Author(s):  
Yelmida Azis ◽  
Cory Dian Alfarisi ◽  
Komalasari Komalasari ◽  
Khairat Khairat ◽  
Yusnimar Sahan

Hydroxyapatite (HAp, Ca10(PO4)6(OH)2) is the most stable form of calcium phosphate and widely used in various medical applications, mainly in orthopedics and dentistry due to its close similarities with the inorganic mineral component of bone and teeth. This study aims to synthesize hydroxyapatite from duck eggshell using the precipitation method. The duck eggshell was calcined, hydrated (slaking) and underwent carbonation to form Precipitated Calcium Carbonate (PCC).  Afterwards, (NH4)2HPO4 was added to produce HAp by varying the molar ratio of Ca/P by 1.67, 1.77 and 1.87 and stirring speed by 200, 250, 300rpm under basic condition (pH 10 – 11). The best results were obtained at a molar ratio of 1.77 with 200rpm stirring speed. Furthermore, the X-ray Diffraction (XRD) analysis showed that its crystals were hexagonal with sizes of 23.062nm, in the absence of other crystalline phases. Therefore, the hydroxyapatite was obtained in the agglomerates form with a specific surface area of ??55.929m2/g.


Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2663
Author(s):  
Chinmoyee Das ◽  
Sandeep Tamrakar ◽  
Alper Kiziltas ◽  
Xinfeng Xie

The strive for utilization of green fillers in polymer composite has increased focus on application of natural biomass-based fillers. Biochar has garnered a lot of attention as a filler material and has the potential to replace conventionally used inorganic mineral fillers. Biochar is a carbon rich product obtained from thermochemical conversion of biomass in nitrogen environment. In this review, current studies dealing with incorporation of biochar in polymer matrices as a reinforcement and conductive filler were addressed. Each study mentioned here is nuanced, while addressing the same goal of utilization of biochar as a filler. In this review paper, an in-depth analysis of biochar and its structure is presented. The paper explored the various methods employed in fabrication of the biocomposites. A thorough review on the effect of addition of biochar on the overall composite properties showed immense promise in improving the overall composite properties. An analysis of the possible knowledge gaps was also done, and improvements were suggested. Through this study we tried to present the status of application of biochar as a filler material and its potential future applications.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alexander Groetsch ◽  
Philippe K. Zysset ◽  
Peter Varga ◽  
Alexandra Pacureanu ◽  
Françoise Peyrin ◽  
...  

AbstractBone is an intriguingly complex material. It combines high strength, toughness and lightweight via an elaborate hierarchical structure. This structure results from a biologically driven self-assembly and self-organisation, and leads to different deformation mechanisms along the length scales. Characterising multiscale bone mechanics is fundamental to better understand these mechanisms including changes due to bone-related diseases. It also guides us in the design of new bio-inspired materials. A key-gap in understanding bone’s behaviour exists for its fundamental mechanical unit, the mineralised collagen fibre, a composite of organic collagen molecules and inorganic mineral nanocrystals. Here, we report an experimentally informed statistical elasto-plastic model to explain the fibre behaviour including the nanoscale interplay and load transfer with its main mechanical components. We utilise data from synchrotron nanoscale imaging, and combined micropillar compression and synchrotron X-ray scattering to develop the model. We see that a 10-15% micro- and nanomechanical heterogeneity in mechanical properties is essential to promote the ductile microscale behaviour preventing an abrupt overall failure even when individual fibrils have failed. We see that mineral particles take up 45% of strain compared to collagen molecules while interfibrillar shearing seems to enable the ductile post-yield behaviour. Our results suggest that a change in mineralisation and fibril-to-matrix interaction leads to different mechanical properties among mineralised tissues. Our model operates at crystalline-, molecular- and continuum-levels and sheds light on the micro- and nanoscale deformation of fibril-matrix reinforced composites.


2021 ◽  
Vol 7 (31) ◽  
pp. eabg3089
Author(s):  
Shixuan Chen ◽  
Hongjun Wang ◽  
Valerio Luca Mainardi ◽  
Giuseppe Talò ◽  
Alec McCarthy ◽  
...  

Biomaterials without exogenous cells or therapeutic agents often fail to achieve rapid endogenous bone regeneration with high quality. Here, we reported a class of three-dimensional (3D) nanofiber scaffolds with hierarchical structure and controlled alignment for effective endogenous cranial bone regeneration. 3D scaffolds consisting of radially aligned nanofibers guided and promoted the migration of bone marrow stem cells from the surrounding region to the center in vitro. These scaffolds showed the highest new bone volume, surface coverage, and mineral density among the tested groups in vivo. The regenerated bone exhibited a radially aligned fashion, closely recapitulating the scaffold’s architecture. The organic phase in regenerated bone showed an aligned, layered, and densely packed structure, while the inorganic mineral phase showed a uniform distribution with smaller pore size and an even distribution of stress upon the simulated compression. We expect that this study will inspire the design of next-generation biomaterials for effective endogenous bone regeneration with desired quality.


Author(s):  
Sandra Villagómez-Estrada ◽  
José F Pérez ◽  
Sandra van Kuijk ◽  
Diego Melo-Durán ◽  
Asal Forouzandeh ◽  
...  

Abstract The aim of the present study was to evaluate the effect of trace mineral nutrition on sow performance, mineral content, and intestinal gene expression of neonate piglets when inorganic mineral sources (ITM) were partially replaced by their organic mineral (OTM) counterparts. At 35 d post-mating, under commercial conditions, a total of 240 hyperprolific multiparous sows were allocated into three experimental diets: 1) ITM: with Zn, Cu, and Mn at 80, 15, and 60 mg/kg, respectively; 2) Replace: with a 30 % replacement of ITM by OTM, resulting in ITM + OTM supplementation of Zn (56 + 24 mg/kg), Cu (10.5 + 4.5 mg/kg), and Mn (42 + 18 mg/kg); and 3) Reduce and replace (R&R): reducing a 50 % of the ITM source of Zn (40 + 24 mg/kg), Cu (7.5 + 4.5 mg/kg), and Mn (30 + 18 mg/kg). At farrowing, 40 piglets were selected, based on birth weight (light: < 800 g, and average: > 1,200 g), for sampling. Since the present study aimed to reflect results under commercial conditions, it was difficult to get an equal parity number between the experimental diets. Overall, no differences between experimental diets on sow reproductive performance were observed. Light piglets had a lower mineral content (P < 0.05) and a downregulation of several genes (P < 0.10) involved in physiological functions compared to their average littermates. Neonate piglets born from Replace sows had an upregulation of genes involved in functions like: Immunity and Gut barrier, compared to those born from ITM sows (P < 0.10), particularly in light piglets. In conclusion, the partial replacement of ITM by their OTM counterparts represents an alternative to the totally inorganic supplementation with improvements on neonate piglet gene expression, particularly in the smallest piglets of the litter. The lower trace mineral storage together with the greater downregulation of gut health genes exposed the immaturity and vulnerability of small piglets.


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