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Protein expression of growth factors involved in fracture healing and osteoporosis were investigated in ovariectomised (OVX) rat fracture model using histological and immunohistochemical analysis.
Fracture healing is a complex biological cascade regulated by many systemic and local factors including growth and differentiation factors, hormones, cytokines and extracellular matrix (ECM) components.
The relationship of MMP/TIMP with other growth factors and their role in osteoporotic fracture healing has not been well documented.
It may also partly explain the weaker mechanical properties reported in osteoporotic fractures [2-4].
Down-regulation of IGF-I, following estrogen deficiency may partly account for the delayed healing and the associated changes in ECM composition and inferior mechanical properties seen in osteoporotic fractures.

From Fig. 1 to Fig. 3, it can be seen: 1) From the affecting depth of compaction point of view, the larger energy level, the deeper affecting depth.
It is apparent from Table 3 that the SPT counts were significantly increased in a certain sphere of influence, which directly reflects affecting depth.
For 8000kN.m energy, the affecting depth is 15.0m. the counts of SPT of zone A1 were significantly greater than zone A2, which indicates that the spacing of 2D is better than 2.5D; The affecting depth of 6500kN.m is about 12.0m, but the counts of SPT of zone B2 were significantly less than zone B1, indicating 7m2 area at this depth is not good as 5m2 area, but in the upper of the subsoil 7m2 is greater than 5m2 area; For 3000kN.m level, the affecting depth is only about 7m.
The tamping energy, spacing, hammering times, all the factors have great influence to the thickness of eliminating collapsibility.
Thickness of eliminating collapsibility depends on energy level, tamping spacing, hammering frequency, engineering properties of soil and other factors.

The mechanical limitations of HAp can be overcome by adding bioinert materials with superior mechanical properties.
This will help to take the advantages of the bioactive properties of the coating developed along with the mechanical properties of the metallic substrate.
Ponsonnet et al. [26] showed that the cell behavior on biomaterial surface is largely affected by surface properties like roughness, texture, chemical composition and morphology.
Li, T.Q.Lei, Factors influencing phase compositions and structure of plasma sprayed hydroxyapatite coatings during heat treatment, Appl.
Heimann, Plasma-Sprayed Hydroxylapatite-Based Coatings: Chemical, Mechanical, Microstructural, and Biomedical Properties, J.

Therefore, the mechanical properties of previous models are merely calibrated under quasistatic condition.
Calibration of the DEM model for mechanical properties The properties of DEM model are directly related with the meso-parameters, e.g.
So the model should be calibrated to ensure the equivalent properties with cast iron.
The comparison of properties between model and cast iron Mechanical properties Young’s modulus E [Gpa] Poisson’s modulus υ Compressive strength σ [Mpa] Density ρ [kg/m3] Cast iron 103.5~129.7 0.23~0.25 620~765 7340 DEM model 110.8 0.217 678 7335 Fig. 3 Numerical modeling of SHPB test Fig. 4 Stress-strain curve of the model under 2526s-1 Oblique plane impact test.
Oblique plane impact test was conducted to further examine the dynamic properties of the model.

Such micro-crack is shown in fig. 4b, where it is propagate through the heat affected zone of the cladding layer weld.
This low plasticity of the cladding layer is an in-service crack initiation factor, characteristic of thermo  mechanical fatigue phenomenon, given the heating and cooling cycles of the plant.
On the macro-fractographic fracture surfaces examined were also identified stress corrosion cracking (fig. 7 - sample F3) which represent stress concentrations factors and sources of the crack propagation in the shell thickness direction.
The current metallurgical status of materials of shells 2 and 3 are similar, as attested by the structure and mechanical properties obtained by short-term tests, whose results do not vary significantly.
[2] API RP 581 Risk - Based Inspection Technology, Second Edition, American Petroleum Institute, Washington DC, USA, 2008; [3] API RP 571 Damage Mechanisms Affecting Fixed Equipment in the Refining Industry, Second Edition, American Petroleum Institute, Washington DC, USA, 2011; [4] Pierre R.

While hot forming achieved higher dimensional accuracy, it resulted in slightly lower mechanical properties.
Key parameters during the forming and quenching stage include heat transfer coefficients (HTC), press velocity (which affects the cooling rate), and other factors influencing formability, such as lubrication and tooling surface conditions [20], [21].
The transfer of heat is a key process that affects the evolution of the mechanical properties in the product.
However, 60 minutes holding time in the SHT furnace and ageing at 180 °C allows for the recovery of mechanical properties.
As shown, contact pressure has a positive effect on mechanical properties compared with the water quenched (WQ) samples.

To achieve these properties of structures it is necessary to define the needed number of fastening elements in separate areas of the roof – in detail, see EN 1990, EN 1991-1-4 a ETAG 006.[2] The number of fastening elements is closely connected with the thermal properties of the roof composition.
The heat transfer coefficient U [W/m2K] is one of the elementary and most clarifying values to characterize the thermal properties of selected building construction.
In the table 2 there are defined materials which formed individual models and their properties.
Table 2 – Selected properties of materials used in models Layer name λ [W/mˑK] Cu [J/KgˑK] р[Kg/m3] 1.
Unfortunately these values cannot be used in structural design because each composition consist of different order of layers, differ in material thickness, structural composition or material properties which affect value of the pint heat transfer coefficient.

Furthermore, without a coolant, titanium alloys are more susceptible to reacting with atmospheric gases which can also adversely affect their mechanical properties.
Table 2 shows the physical properties of the tested water-miscible cutting fluid at different concentration ratios.
The best combinations of the control factors for minimising the tool wear when turning Ti-6Al-4V are 10% fluid concentration, cutting speed of 58 m/min and feed rate of 0.1 mm/rev using uncoated carbide cutting tool H13A.
This can be ascribed to its superior combination of high hot hardness, toughness, and high transverse rupture strength properties [12].
A high regression value (R2 is above 99%) as well as very low model error (0.5%) indicates that all important factors are considered in this study.

Using burnt clays in mortars may influence the number of their properties; the increase in compressive and flexural strength values is monitored in particular.
If it is assumed that the durability of these composites is connected with the number of microcracks affecting them, and their ability to resist the propagation of such cracks, it is possible to quantify this durability using different brittleness parameters.
Due to having different properties to those required from the raw material additives used in ceramic products, it is often impossible to utilize such waste in ceramics in production.
These compounds are more resistant to the effect of acid in the atmosphere in comparison with the product of lime carbonation in lime mortars, and they generally increase corrosion resistance and improve mechanical properties, which lengthens mortar durability.
Influence of metakaolin on the properties of mortar and concrete: A review, Applied Clay Science, 43 (2009) 392-400

The mechanical strength of pulp capping material based on carbonate apatite and silica calcium-phosphate composite (CO3Ap-SCPC) is one of the key factors for the success of the material in protecting the vitality of the pulp during the formation of apatite and dentin reparative.
Modifying the CO3Ap cement with the addition of various concentration of SCPC and Ca(OH)₂ expected could improve the mechanical properties of this cement [3,16].
Conclusion The addition of various concentrations of SCPC and Ca(OH)2 have an effect in forming CO₃Ap and also improving the mechanical properties of the cement.
Braga, Ion Release and Mechanical Properties of Calcium Silicate and Calcium Hydroxide Materials Used for Pulp Capping, Int.
Hasratiningsih, Mechanical Strength Properties of Injectable Carbonate Apatite Cement with Various Concentration of Sodium Carboxymethyl Cellulose, Key Eng.