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JSEMAT Vol.7 No.4 , October 2017
Effect of Adding Sb on Microstructure, Mechanical Properties and in Vitro Degradation Behavior of as Cast Mg-4wt% Zn Alloy for Medical Application
Hadeer I. Mohamed1,2*, Mohamed E. Moussa3, Mohamed A. Waly3, Gamilla S. Al-Ganainy4, Aya B. Ahmed1, Mona S. Talaat1
1 Biophysics Group, Physics Department, Faculty of Science, Ain Shams University, Cairo, Egypt.
2 Department of Neuroscience Technology, College of Applied Medical Sciences in Jubail, Imam Abdulrahman Bin Faisal University, Jubail, Kingdom of Saudi Arabia.
3 Department of Manufacturing Technology, Laboratory of Foundry, Central Metallurgical Research and Development Institute (CMRDI), Helwan, Egypt.
4 Physics Department, Faculty of Science, Ain Shams University, Cairo, Egypt.
Abstract: Magnesium (Mg) and its alloys are one of a novel kind of biodegradable metallic implants which attracted much fundamental research to develop its clinical application. Nevertheless, it has more restrictions in biomedical applications because it degrades too fast at the early stage after implantation, thus commonly leading to some problems such as early fast mechanical loss, hydric bubble aggregation, gap formation between the implants and the tissue. This work aims to study the effect of 0.5 wt% Sb addition on the microstructure, mechanical properties and degradation behavior of as cast Mg-4wt% Zn alloy. The evaluation process was conducted using optical and scanning electron microscopy, X-ray diffraction, tensile and compression tests, in addition to a corrosion study by immersing in simulated body fluid (SBF). Results showed that Sb refines the grain size of the base alloy and also enhances its mechanical properties and degradation rate as well. These were due to the formation of the secondary phase of Mg3Sb2. To get better degradation rate, the Mg-4wt% Zn and Mg-4wt% Zn-0.5wt% Sb alloys are coated with Ca-P using autocatalytic technique. The results demonstrated that the formed coat layer improves the degradation rate of samples under the condition of this study. The current study shows that Mg-4wt% Zn-0.5wt% Sb alloy has good mechanical properties and when it coated by Ca-P, it gave a better corrosion resistance that makes it ideal for biodegradable medical application.
Keywords: Mg Alloy, Mechanical Properties, Autocatalytic Route, Degradation Rate, Calcium Phosphate Coating
Recently biodegradable metallic implants have notable consideration in biomaterial field. Their degradation after a certain time, leads to reduce the call for extra surgery to remove the short-term implant. Mg alloy has a great interest as a biodegradable implant because its biocompatibility as it found naturally in bone; it can directly influence bone-resorbing cells and consider as a vital factor for bone metabolism. Many clinical in vivo and in vitro studies have been recommended Mg-base implants due to their good biocompatibility and their mechanical properties comparable with those of natural bone [1] [2] . The Mg density is (1.7 - 2.0 g/cm3) which is a slightly lower than that of natural bone (1.8 - 2.1 g/cm3), and its elastic modulus (41 - 45 GPa) is closer to those of the human bone (10 - 40 GPa) [3] . All these properties reduce the probability of stress shielding effect observed in the case of higher modulus materials such as titanium alloys [4] . Unfortunately, the application of magnesium as an implant has some restrictions such as its high degradation rate, especially in an aggressive chloride medium like a human body. This implant may degrade and reduce its mechanical properties before new tissues are completely healed [5] . Hence element alloying and surface modification are effective methods to improve rapid degradation of Mg and also to enhance their mechanical properties besides aiding in decrease corrosion.
Many elements such as Ca, Mn, Al, Zn, Si, and Sr are used as alloying elements with magnesium. In the present research, zinc (Zn) and antimony (Sb) were chosen as alloying elements. Zn is a commonly used as alloying element with magnesium and its strengthening effect is only following aluminum. It furthermore assists to eliminate the harmful effect of impurities such as iron and nickel, thus improving the corrosion resistance of magnesium alloys [6] . Also, 4wt% Zn which was chosen in this work was reported to be the optimum Zn content for tensile and mechanical strengthening over the range of alloying [7] . Moreover, zinc is vital for many biological functions, plays a fundamental role in the metabolic activities of the body's enzymes, essential for cell division and the creation of protein and DNA. Whereas excessive exposure toxicity of Zn is rare, Zn shortage has a harmful effect on growth, neuronal development, and immunity [4] . On the other hand, it is reported that the addition of 0.4 wt% Sb gives high mechanical properties, however, at the higher Sb level of 0.7 wt% the strength and hardness decrease [8] . Therefore, in present work, 0.5 wt% Sb is added to Mg-4wt% Zn alloy to study its effect on mechanical properties and degradation behavior. On the other hand the biological effect of Sb still needs more experimental research.
To improve corrosion resistance and biocompatibility of prepared alloys, the surface will be coated with Ca-P layer. Ca and P are the major elements in bone minerals. Thus, Ca-P coatings, especially osteoconductive minerals such as hydroxyapatite (HA) and tricalcium phosphate (TCP), should be useful in constructing new bone and promoting osteointegration around Mg implants [9] . Niu, Jialin, et al. [10] reported that the Ca-P coat improves the corrosion resistance of Mg-Nd-Zn-Zr alloy and reduced the hemolysis rate from 48% to 0.68%. Song, Yang, et al. [9] showed that both the HA and FHA (fluoridated hydroxyapatite) coating could promote the nucleation of osteoconductive minerals (bone-like apatite or β-TCP), while the precipitates on the uncoated Mg-Zn alloy in modified simulated biological fluid had low Ca/P molar ratios, which delayed bone-like apatite formation.
Several coating techniques have been investigated, but due to the special properties of Mg as high reactivity and relatively low melting point (650˚C), not all coating procedures can be suitable for Mg [11] . Seeing that the biomimetic coating would be helpful in coating biodegradable substrates such as Mg-alloys, it reduces the incubation times in SBF during the coating procedure [12] . As reported this resulted in the formation of non-uniform and porous Ca-P coating on Mg substrates [13] , in addition to hydrogen bubbles formed on the Mg surface during immersion. When using a Sol gel technique for Mg substrates, the temperatures should be less than the melting point of pure Mg (650˚C) [14] to avoid affecting the surface integrity of the Mg substrate. Accordingly, in the present work autocatalytic technique which reported in previous studies [15] [16] [17] is used. This technique is simple, economical, does not require high temperature and setup in short time which minimize the chance of degradation.
So as there is little information on Mg-Zn-Sb, as biodegradable implant, the present work aims to study the effect of Sb addition on microstructure, mechanical and degradation behavior of Mg-4wt% Zn alloy. Also, we intend to study the effect of the autocatalytic technique on degradation to get an appropriate alloy for load bearing medical applications.
2.1. Material Preparation
The base composition of the studied alloy was Mg-4wt% Zn. 0.5 wt% Sb was added to the base alloy in order to investigate its effect on microstructure, mechanical properties and the degradation rate. The alloy was prepared from commercial pure Mg (99.8 wt% purity), Zn (99.98 wt% purity), and Sb (99.99 wt% purity). Before melting process a charge calculations are performed and with respect to experience, the 90% efficiency of melting process and 10% losses during melting can be estimated and be in consideration. After that melting the charge of about 1.5 kg of each alloy in a graphite crucible placed in an electric resistance furnace. The melting and pouring processes were carried out under gas mix consists of tetrafluoroethane (CF3CH2F, HFC-134a, 1 vol.%) and carbon dioxide (CO2, Bal.). Firstly, commercial Mg ingots were melted to above 650˚C, and then Zn with melting point 419˚C was added into Mg melt. After that, the melt were heated to about 720˚C, and then Sb with melting point 630˚C was added into Mg melt. The melt was manually stirred for 3 min using a stainless steel rod, and then was held for additional 15 min in order to get full homogenization. Before pouring the melt, test sample of the melt is required to make a chemical analysis correction using X-ray fluorescence (XRF) analyzer. Depending on the test result a correction process is required either by diluting (adding pure Mg) or concentrating (adding alloying element as Sb or Zn or both) to get the required alloy composition. After that, the slag was removed, and then the melt was poured at about 720˚C into a preheated cast iron mold up to 100˚C with dimensions of outer diameter (100 mm), inner diameter (50 mm) and length (250 mm). The chemical compositions of the prepared alloy were determined by using X-ray fluorescence (model Axios advanced-PANALYTCAL, The Netherlands).
2.2. Microstructure Characterization
All metallographic specimens were cut at the same position of 10 mm from the bottom of castings. Grinding of the specimens were carried out on wet SiC papers, down to grit size 1200 then followed by fine polishing with diamond, particle size from 1 to 6 µm, on nylon cloth, rinsing with water and ethyl alcohol. For best results, the polished surface must be mirror like, i.e., free from any residual layer. After that, the specimens are etched by solution with 10 ml nitric acid, 30 ml acetic acid, 40 ml water, and 120 ml ethanol for 2 - 3 min [18] .
The microstructures of the specimens were analyzed by optical microscope (OM) (Zeis model Axiotech, Germany). Six OM micrographs were taken for each sample from the observed area at a magnification of 100×. The average grain size of α-Mg was measured by using an image analyzer. All α-Mg grains existed in one picture taken from the observed area were measured.
Phase constituents of samples were analyzed by X-ray diffraction (XRD) (model X'PERT PRO, The Netherlands) using Cu-Kα (K = 1.54056 ) radiation in step scan of 2θ from 20˚ to 80˚ with an increment of 0.02˚ and a scanning speed of 4˚/min. Scanning electron microscope (Inspect S50.Fel, The Netherlands) equipped with an energy dispersive X-ray spectrometer (EDS) were used to conduct microstructure analysis.
2.3. Mechanical Tests
Tensile and compression tests were carried out using LFM-L-20KN Computer controlled and digital display electromechanical universal testing machine (model LFM-L-20KN (bench top), Switzerland). The dimensions of a cylindrical tensile specimen are shown in Figure 1 according to ASTM E8M [19] . Three specimens were tested with a strain rate of 0.1 mm/min for each alloy. Cylindrical samples with a diameter of 10 mm and a height of 8 mm were used for the compression test.
2.4. Sample Coating
2.4.1. Pre-Treatment
Before coating, samples were cut into discs (10 mm diameter and 2 mm thickness). Each sample was cleaned with acetone, 70% ethanol, and finally distilled water for 15 min each, in an ultrasonic cleaner. Then samples were etched in Kroll's reagents for 10 min at 20˚C next washed with distilled water to remove the native oxide surface. Afterward, samples were immersed in 10 M NaOH bath at 60˚C for 24 h followed by heating and holding at 100˚C for 1 h [15] [16] [17] .
2.4.2. Coating by Autocatalytic Bath
After the pretreatment step, samples were immersed in an acidic autocatalytic bath under magnetic stirrer for 2 h at 60˚C ± 2˚C at pH 5 to get different phases Ca-P coatings on samples. The composition of acidic bath was reported in previous work [15] [16] [17] .
2.4.3. Characterization of Coating
Surface morphology and the chemical compositions of the deposited layer were analyzed by field emission scanning electron microscope (Quanta 250) with EDS. Structure of coated layer was analyzed by X-ray diffraction (XRD) with similar condition used for microstructure composition.
Figure 1. Dimensions of the tensile specimen (mm) [19] .
2.5. Corrosion Evaluation by Immersion in Simulated Body Fluid (SBF)
Corrosion resistance by in vitro degradation method was obtained by weight loss measurements which were performed by immersing the alloy samples in SBF. The chemical composition of c-SBF in comparison to human blood plasma was reported in several studies [20] . The pH value of the initial solution was adjusted to 7.4. The whole test cell was maintained at 37˚C ± 1˚C in a shaking water bath to prevent aggregation of the precipitates on sample surfaces [15] . In this test two categories of samples (non-coated (bare), coated) were studied. The samples were immersed for 14 days in SBF solution with refreshment after 3 days. The refreshment was done to simulate the metabolic environment of the human body and study the formed layer. The appearance and microstructure of the specimens were characterized by SEM with EDS. The pH value of the solution was measured by a pH meter with an accuracy of ±0.01.
The sample weight was measured every 24 hours of immersion after removal of corrosion products with a chromic acid. The degradation rates were calculated by the following equation according to the standard:
D R = Δ m A T ρ (1) [21]
where: DR is the degradation rate (mm/hr), Δ m is the mass loss (g), A is the initial surface area exposed to the SBF (mm2), T is the immersion time (hr), and ρ is the density of tested sample (g/mm3).
The concentrations of Ca and P ions in SBF after immersion of coated Mg-4wt% Zn and Mg-4wt% Zn-0.5wt% Sb for 14 days were measured using a UV-Vis spectrophotometer and the specific kits (Biodiagnostic, Diagnostic and research reagents, Egypt) at wavelength 640 nm, 585 nm for phosphorus and calcium respectively.
3.1. Chemical Composition
The chemical compositions of the prepared alloy were determined using X-ray fluorescence (XRF) analyzer. Table 1 showed the obtained chemical composition of the investigated alloys.
3.2. Phases and Microstructure Characterization
Figure 2 shows the XRD results and the optical microstructure of the as-cast prepared alloys. As shown in Figure 2(a), α-Mg and MgZn phases are the only
Table 1. The chemical composition of the prepared alloys (wt%).
Figure 2. (a) XRD patterns of as-cast alloys Mg-4wt% Zn and Mg-4wt% Zn-0.5wt% Sb, optical micrographs of as-cast alloys (b) Mg-4wt% Zn and (c) Mg-4wt% Zn-0.5wt% Sb.
constituents of the Mg-4wt% Zn alloy. These two phases have also been reported to exist in the as-cast microstructure of an Mg-4wt% Zn alloy [22] . In the Sb containing materials, however, some new peaks corresponding to the Mg3Sb2 intermetallic phase appear in the patterns. Figure 2(b) & Figure 2(c) show that the coarse dendritic structure of the Mg-4wt% Zn alloy is generally refined from about 100 µm (Figure 2(b)) to about 53 µm after the addition of 0.5 wt% Sb (Figure 2(c)).
For clear observations of the constitutive phases, SEM micrographs with EDS and elemental mapping of Mg, Zn and Sb of investigated alloys are shown in Figure 3 & Figure 4, respectively. Figure 3(a) shows the microstructure of the Mg-4wt% Zn alloy which consists of the primary α-Mg matrix (region A), while the second phase appears as white island-like (region B) which was identified by EDS to be composed of Mg and Zn elements. Combined with the XRD results shown in Figure 2(a), it is found that the island-like particles are most likely the MgZn particles and thus the lamellar eutectic structure consists of α-Mg +
Figure 3. SEM micrographs with EDS showing intermetallic phases in as-cast alloys (a) Mg-4wt% Zn and (b) Mg-4wt% Zn-0.5wt% Sb.
Figure 4. (a) SEM micrograph and EDS elemental mapping of (b) Mg and (c) Zn in as-cast alloy Mg-4wt% Zn and (d) SEM micrograph and EDS elemental mapping of (e) Mg, (f) Zn and (g) Sb in as-cast alloy Mg-4wt% Zn-0.5wt% Sb.
MgZn. In Sb-added alloy (Figure 3(b)), a new rod shape particles contain Mg and Sb is appeared (region C) which was detected by XRD as Mg3Sb2 (Figure 2(a)).
Figure 4 shows EDS elemental mapping of Mg, Zn and Sb in the investigated alloys. It can be seen that the non-uniform distribution of Zn (Figure 4(c)) in the interdendritic regions of α-Mg (Figure 4(b)). With addition of 0.5 wt% Sb, the distribution of Sb is mostly at the boundaries of the α-Mg dendrites (Figure 4(g)) and the uniform distribution of Zn at dendrites boundaries (Figure 4(f)).
3.3. Mechanical Properties
The ultimate tensile strength, elongation and Compressive strength of investigated alloys, are summarized in Table 2.
3.4. Characterization of Coating
It is observable that autocatalytic bath changes the morphologies of the based alloys as shown in Figure 5. Homogeneous coating was observed for both alloys. At higher magnification it was found that bulk coating was formed after immersion of Mg-4wt% Zn in the bath with distribution of white grain on its surface (Figure 5(b)). EDS analysis of this layer demonstrates the presence of Mg, O
Table 2. The ultimate tensile strength, elongation and Compressive strength of investigated alloys.
Figure 5. SEM micrographs with EDS showing the coat formed on the surface of Mg-4wt% Zn ((a)-(c)), Mg-4wt% Zn-0.5wt% Sb ((d), (e)).
with traces of phosphorus and calcium on the surface of the alloy (Figure 5(c)). While after addition of Sb, an agglomerate of fine grains covers the surface of the alloys (Figure 5(e)). EDS of this layer consist of higher amount of Ca, P in addition to Na ions. The addition of Sb allows the precipitation of Ca-P layer as a nucleation for hydroxyapatite (HA). The atomic calcium phosphate ratio n(Ca)/n(P) value suggest that formed layer may be dicalcium Phosphate dihydrate (DCPD), also known as brushite which act as a precursor phase.
The XRD patterns Mg-4wt% Zn and Mg-4wt% Zn-0.5wt% Sb alloys after coating (Figure 6) show existence of Mg(OH)2 peaks which confirmed by SEM results. It is noted that Mg-4wt% Zn displays high intensity of Mg(OH)2 peaks compared with Mg-4wt% Zn-0.5wt% Sb.
Other than brushite phase cannot be detected by XRD as it is very thin and non uniform layer. Improvement of the formed layer will be considered in future work by increasing the immersion time and pH of autocatalytic bath.
3.5. Corrosion Evaluation by Immersion in Simulated Medium
The average mass loss and the rate of degradation of Mg-4wt% Zn and Mg-4wt% Zn-0.5wt% Sb alloys before and after coating during 14 days of immersion in SBF are illustrated in Figure 7.
The change in mass is an indicator for the degradation of the alloy samples. Figure 7 illustrates that, the coated sample of Mg-4Zn showed the lowest rate of degradation in the first 24 hr of immersion. As the sample has a porous, and
Figure 6. XRD patterns of Mg-4wt% Zn and Mg-4wt% Zn-0.5wt% Sb samples after coating.
Figure 7. The degradation rate during immersion of coated and bare alloys of Mg-4Zn and Mg-4Zn-0.5Sb.
dense layer of Mg(OH)2, which can reduce the corrosion rate. However, more than 48 hr of immersion, the degradation rate of both coated samples increased. As the protective Mg(OH)2 layer converted into a more soluble MgCl2. This will cause the coated Mg-4Zn alloys to expose to the solution and stimulate the degradation. As well, the coated Mg-4Zn-0.5Sb sample displayed high rate of degradation due to dissolving of brushite coat. On the other hand, the degradation rate of the bare samples of Mg-4Zn and Mg-4Zn-0.5Sb decreased due to formation of Mg(OH)2 protective layer.
By refreshing the solution after 3 days of immersion, it is found that, the degradation rate increased again for all the samples. This caused by Cl− ions which accelerate the electrochemical reaction rate from magnesium and leads to more degradation of the Mg matrix. Seeing that the exposure period continues, the corrosion rate reached a steady state as the rate of formation of Mg(OH)2 is equal to destruction of it by MgCl2. At the end of immersion time it is observed that the Mg-4Zn-0.5Sb samples shows the lowest rate of degradation specially the coated one.
Figure 8 shows the micrograph of the surface of Mg-4Zn and Mg-4Zn-0.5Sb alloys after immersion in the SBF solution for 336 h. Figure 8(a), Figure 8(d), Figure 8(g), and Figure 8(j)) show the surface cracks which formed from dehydration of the surface layer in the air [23] . Existence of cracks accelerates corrosion of the substrate by making solution come into contact with the matrix [24] . The bare Mg-4Zn alloy and Mg-4Zn-0.5Sb (Figure 8(a), Figure 8(g)) showed deeper
Figure 8. SEM micrographs of samples surface after SBF immersion. ((a)-(c)) bare Mg-4Zn, ((d)-(f)) coated Mg-4Zn, ((g)-(i)) bare Mg-4Zn-0.5Sb, ((j), (k)) coated Mg-4Zn-0.5Sb.
and thicker cracks than coated alloys (Figure 8(d), Figure 8(j)). The EDS analysis showed the presence of Mg(OH)2 consistent with the atomic ratio of Mg to O (1:2) on the surface of bare Mg-4Zn (Figure 8(c)). The EDS results of the corroded layer on coated samples (Figure 8(f), Figure 8(k)) showed the existence of Mg and O as well as amounts of Ca and P, which represents formation of HA. As observed in EDS results that the bare samples have trace amounts of Ca and P in compare with the coated samples.
This consequence points that the coated samples are more successful to form nucleation of Ca-P which initiates the formation of HA. To confirm that, the concentrations of Ca and P ions in SBF after immersion of coated Mg-4Zn and Mg-4Zn-0.5Sb for 14 days are measured as presented in Figure 9.
It is illustrious that the difference in the electronegativity values between Mg of 1.31, Zn of 1.6 and Sb of 2.05, provides the Sb more tendencies to form a compound with Mg than with Zn [8] [25] . Therefore, all of the Sb added to Mg-4wt%
Figure 9. Concentrations of Ca and P ions in SBF after immersion of coated alloy samples for 14 days.
Zn alloy, is consumed to form Mg3Sb2 particles [8] . The refining effect of Sb in cast magnesium alloys has attracted some attention [26] [27] [28] . It has been reported that small additions of Sb had a great effect on the microstructural refinement and mechanical properties of the cast Mg-5%Sn alloy. Adding Sb to ZA84 [27] and AZ91 [26] has also resulted in microstructural refinement and improved room and high-temperature mechanical properties. Based on the SEM observations (Figure 4(d), Figure 4(g)), where no Mg3Sb2 compound is detected inside the Mg grains and all particles are found to be formed inside the interdendritic spaces. Therefore, the segregation of Mg3Sb2 particles at the liquid/ solid interface would restrict the growth of α-Mg dendrites during solidification and thus refine the structure. These results are also confirmed by the previous work reported by R. Alizadeh et al. [8] . Also the addition of 0.5 wt% Sb could improve the mechanical properties of Mg-4wt% Zn alloy. Owing to the relation of mechanical properties with the microstructure of the investigated alloys, the improved mechanical properties of the Sb-added alloy outcome from their microstructures. It is well known that the fine microstructure is usually beneficial to tensile properties of engineering alloys. According to Griffith's theory [29] , the fracture stress of a material increases with decreasing grain size, in inverse proportion to the square root of the grain size. As shown before, the addition of Sb into the base Mg-4wt% Zn alloy cause grain refinement. Therefore, that leads to improve mechanical properties of the as-cast Sb-added alloys which is biocompatible with mechanical properties of cortical bone [30] in comparison with the base alloy and pure Mg [24] . It's clear that the addition of Sb leads to delay the loss of the mechanical properties of the binary Mg-4wt% Zn alloy during implantation
For a closer explanation, in the early stage of an immersion, Mg matrix of bare samples dissolved and transformed into the stable Mg2+ ion (Equations ((2), (3))). This dissolution of Mg is associated with release H2 bubbles observed after immersion and OH− ions which lead to the increase pH of SBF [31] . After that, a protective layer of Mg(OH)2 is formed (Equation (4)) and prevent solution from direct contact with the substrate. This leads to reduce the degradation rate for a while. However, the aggressive Cl− ions in the medium attack the thin film of Mg(OH)2 and convert it into a more soluble MgCl2 (Equation (5)). So the substrate of the bare samples becomes in contact with the solution again [32] .
Mg → Mg 2 + + 2e − (2)
2H 2 O + 2e − → H 2 + 2OH − (3)
Mg 2 + + 2OH − → Mg ( OH ) 2 (4)
Mg ( OH ) 2 + 2Cl − → MgCl 2 + 2OH − (5)
Equations (2)-(5) [24]
The coated Mg-4Zn sample which has a dense protective layer of Mg(OH)2. This layer protects the sample from degradation at first, but after that the Cl- ions dissolve it into MgCl2 according to (Equation (5)). In case of coated Mg- 4Zn-0.5Sb, the brushite (DCPD) layer is unstable and soluble in SBF especially with increasing pH value. Also brushite convert into HA [33] [34] and form layer against corrosion (Equation (6)).
1 0 CaHPO 4 ⋅ 2H 2 O + 12OH − → Ca 1 0 ( PO 4 ) 6 ( OH ) 2 + 4PO 4 3 − + 3 0 H 2 O (6) [9]
As shown in Figure 9 the increase of Ca and P ion concentrations after immersion is due to partially dissolve of the coated layer within the corrosion. Fortunately the presence of the Ca and P ion, and also the increasing of pH during immersion can encourage HA nucleation. So finally it remarks that the formation of the hydroxyapatite in the SBF is self-generated after a certain period of immersion. The formation of HA not only decrease the degradation rate, but it is also reported that during implantation, the living bone will bond through this apatite layer formed on the surface of implant so the coating step is very helpful.
In this article, the as-cast Mg-4wt% Zn and Mg-4wt% Zn-0.5wt% Sb alloys were investigated as degradable metallic implants. The alloys are mainly composed of the matrix α-Mg and MgZn as secondary phase. The addition of Sb refines the grain size and improves mechanical properties due to the formation of the secondary phase of Mg3Sb2.
Immersion result showed that the Ca-P treatment provides a protective layer that improves the corrosion resistance. The degradation rate measured at the end of immersion time improved from 3.5 mm/yr, 2.5 mm/yr for bare and coated Mg-4Zn respectively to 1.4 mm/yr, 0.7 mm/yr for bare and coated Sb-added alloy respectively. So it is clear that the addition of Sb and coating procedure are very effective steps to enhance degradation behavior.
Cite this paper: I. Mohamed, H. , E. Moussa, M. , A. Waly, M. , Al-Ganainy, G. , B. Ahmed, A. and S. Talaat, M. (2017) Effect of Adding Sb on Microstructure, Mechanical Properties and in Vitro Degradation Behavior of as Cast Mg-4wt% Zn Alloy for Medical Application. Journal of Surface Engineered Materials and Advanced Technology, 7, 69-85. doi: 10.4236/jsemat.2017.74007.
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[19] Annual Book of ASTM Standards (2006) Metals-Mechanical Testing; Elevated and Low-Temperature Tests; Metallography. ASTM International, Vol. 3, Baltimore.
[20] Kokubo, T. and Takadama, H. (2006) How Useful Is SBF in Predicting in Vivo Bone Bioactivity? Biomaterials, 27, 2907-2915.
[21] Fan, J., Qiu, X., Niu, X., Tian, Z., Sun, W., Liu, X., et al. (2013) Microstructure, Mechanical Properties, in Vitro Degradation and Cytotoxicity Evaluations of Mg-1.5 Y-1.2 Zn-0.44 Zr Alloys for Biodegradable Metallic Implants. Materials Science and Engineering: C, 33, 2345-2352.
[22] Jia, H., Feng, X. and Yang, Y. (2015) Influence of Solution Treatment on Microstructure, Mechanical and Corrosion Properties of Mg-4Zn Alloy. Journal of Magnesium and Alloys, 3, 247-252.
[23] Razavi, M., Fathi, M. and Meratian, M. (2010) Fabrication and Characterization of Magnesium-Fluorapatite Nanocomposite for Biomedical Applications. Materials Characterization, 61, 1363-1370.
[24] Bakhsheshi-Rad, H., Idris, M., Abdul-Kadir, M., Ourdjini, A., Medraj, M., Daroonparvar, M., et al. (2014) Mechanical and Bio-Corrosion Properties of Quaternary Mg-Ca-Mn-Zn Alloys Compared with Binary Mg-Ca Alloys. Materials & Design, 53, 283-292.
[25] Liu, Z., Chen, Z., Liu, X. and Tao, J. (2006) Influence of Antimony Addition on Heat Resistance of AE41 Magnesium Alloy. Chinese Journal of Materials Research, 20, 186.
[26] Guangyin, Y., Yangshan, S. and Wenjiang, D. (2000) Effects of Sb Addition on the Microstructure and Mechanical Properties of AZ91 Magnesium Alloy. Scripta Materialia, 43, 1009-1013.
[27] Balasubramani, N., Srinivasan, A., Pillai, U.S., Raghukandan, K. and Pai, B. (2008) Effect of Antimony Addition on the Microstructure and Mechanical Properties of ZA84 Magnesium Alloy. Journal of Alloys and Compounds, 455, 168-173.
[28] Nayyeri, G. and Mahmudi, R. (2010) Effects of Sb Additions on the Microstructure and Impression Creep Behavior of a Cast Mg-5Sn Alloy. Materials Science and Engineering: A, 527, 669-678.
[29] Cong, M., Li, Z., Liu, J. and Li, S. (2014) Effect of Sr on Microstructure, Tensile Properties and Wear Behavior of As-Cast Mg-6Zn-4Si Alloy. Materials & Design, 53, 430-434.
[30] Hall, E. (1970) Yield Point Phenomena in Metals and Alloys. Macmillan, London.
[31] Zhen, Z., Xi, T.-F. and Zheng, Y.-F. (2013) A Review on in Vitro Corrosion Performance Test of Biodegradable Metallic Materials. Transactions of Nonferrous Metals Society of China, 23, 2283-2293.
[32] Song, G., Atrens, A., St John, D., Wu, X. and Nairn, J. (1997) The Anodic Dissolution of Magnesium in Chloride and Sulphate Solutions. Corrosion Science, 39, 1981-2004.
[33] Feng, Q., Cui, F., Wang, H., Kim, T. and Kim, J. (2000) Influence of Solution Conditions on Deposition of Calcium Phosphate on Titanium by NaOH-Treatment. Journal of Crystal Growth, 210, 735-740.
[34] Wen, C., Guan, S., Peng, L., Ren, C., Wang, X. and Hu, Z. (2009) Characterization and Degradation Behavior of AZ31 Alloy Surface Modified by Bone-Like Hydroxyapatite for Implant Applications. Applied Surface Science, 255, 6433-6438.


Whether you have chronic lower back pain, a broken arm or another physical impairment, there are times when doing even basic work around the house presents a massive challenge. Home help can relieve the burden, allowing you to focus on getting better. In many cases, we cover the costs of home help, even beyond the statutory limit. The proviso is that no other person living there is able to run the household.
We can help you to fill out your request for home help and will advise you of any certificates that you might need.
Even if there are no children living in your household, we will cover home help for a period of up to four weeks (maximum eight hours a day) if you cannot continue to run the household yourself due to illness.
You are free to decide who you want to help you around the house. This may be someone you know or a professional assistant. We can help you find a suitable assistant, whether you make an application for us to cover the costs of home help or not. Simply contact your personal consultant to discuss this.
You are receiving treatment as a hospital inpatient or are taking part in an outpatient or inpatient care or rehabilitation programme.
Your doctor certifies that you cannot continue to run your household due to serious illness or the acute worsening of an illness, and are thus dependent on home help.
One parent is in hospital with a sick child and the partner at home needs help with the other children.
If you cannot continue to run your household due to serious illness or the acute worsening of an illness, we will conduct a check and cover home help for a period of up to four weeks (maximum eight hours per day), regardless of whether a child is living in the home or not.
Has your doctor certified that you cannot do any work around the house yourself due to pregnancy or childbirth? In this case, SBK can cover the costs of a home help if no child is yet living in your household.
Home help – how much is your co-payment?
If you need home help provided by your health insurance, you only have to make a co-payment of 10% (at least €5.00 but no more than €10.00 per day). If we organise home help for you, you send the co-payment directly to us. If you organise home help yourself and we reimburse you for the costs, then the co-payment is deducted from the reimbursement amount.
Exception: you are exempt from the co-payment in the case of home help due to pregnancy or childbirth.
Contact us to check in advance whether we can cover the costs of home help for you. We just need a few details. Just call your personal consultant. They will be happy to fill in the application with you and will then send everything to you for you to sign. When you are done, send the signed application to the following address: SBK, 80227 Munich, Germany.
You choose who will help you in your home. We work with many different organisations, including welfare organisations and social welfare agencies in towns and municipalities. The assistant comes to your home, and their costs are covered directly by us.
If you find an assistant yourself, we reimburse the costs up to €9.50 per hour or €76.00 per day.
We do not cover the cost of home help provided by your spouse or a family member related to you within two degrees (parents, grandparents, grandchildren, siblings, step-parents, stepchildren, step-grandchildren, parents-in-law, son or daughter-in-law, spouses of grandchildren, spouse's grandparents, brothers-in-law, sisters-in-law). In this case, however, we can reimburse verified loss of earnings and travel expenses incurred (max. €0.20 per km), up to a maximum of €103.25 per day.
If you are approved for less than eight hours per day, you will be reimbursed on a pro rata basis.


Government of India introduced simplified procedures to sanction CENVAT credit to exporters of services. This fecility is available for service tax registrants registered under rule 5 of CENVAT credit rules 2004 and application for CENVAT credit filed on or before 31st March, 2015.
Specimen format of Additional document required to claim CENVAT credit to such exporters of services is attached along with this post below as pdf format. Complete notification and required format of additional documents required to be submitted for refund of CENVAT credit to such service exporters is given under in pdf format.
Machhindra: On 10 February 2016 how can cenvat credit availed ?
Prakaash Sharma : On 17 August 2016 We are a non STP unit located at Indore. We are exporting Software to USA and India as well. We need a short and clear decision (followed by case law, if any) as to whether we can avail CENVAT or service tax refund on input services, mainly on rent paid for our premises. Further, we need to set-off the service tax payable on domestic billing out of the service tax we paid with Rent & internet services; is it lawful. Please suggest! Looking forward for your kind cooperation and guidance.


Despite progress on some fronts, gender inequalities remain pervasive in every dimension of sustainable development; and in many areas, progress is too slow to achieve the SDGs by 2030. Rural women make up over a quarter the world population and majority of the 43 per cent of women in agricultural labour force in developing countries. Yet, they are disproportionately affected by poverty, exclusion and the effects of environmental and climate change. Virtually every gender and development indicator for which data are available reveals that globally, rural women fare worse than rural men and urban women. This is clearly expressed in the gaps in rural women's and girls' access to infrastructure, services, and social protection.
Lack of access to affordable and clean energy at the household level has particular implications for rural women and girls. Where access to clean and affordable energy is lacking, women and girls may spend large portions of their day performing laborious and physically draining tasks such as collecting biomass fuels, manually processing foodstuffs and pumping water.
In areas of fuel scarcity, fuel collection can take up as much as five hours per day—time that could otherwise be used for education, rest or leisure. Women and girls are also disproportionately affected by long-term health problems resulting from household air pollution and carrying heavy fuel loads. In countries that rely heavily on solid biomass and coal for cooking, women account for 6 out of every 10 premature deaths through household air pollution caused by unclean fuels and inefficient technologies.
When safe drinking water is not available on premises, the burden of water collection and treatment largely falls on women and girls, who are responsible for water collection in 80 per cent of households without access to water. This work is arduous and will only become harder given increasing water scarcity. It exacts a toll on women's health, can compromise their safety and takes up time that could otherwise be spent on paid work, education or leisure.
The absence of adequate sanitation facilities exposes women and girls to illness, risks to their safety and violence—hampering their ability to go to school, earn an income and move around freely. Conversely, enhanced access to safe drinking water and sanitation has been associated with increases in women's productive activities as well as children's school attendance. Provision of safe drinking water, that is, continuous piped water at the household level, has the greatest health benefits and lowest drudgery costs. Extending the reach of water grids to underserved communities is hence an important priority.
Rural women's civil society organizations, enterprises and cooperatives are critical in gathering and uniting rural women, supporting their voice, agency and representation in the political and economic spheres, and enabling them to influence the decisions and institutions that affect their lives. Around the world, rural women have organized to advocate for the infrastructure, services, and social protection necessary for their wellbeing, livelihoods, and resilience. Rural women have mobilized to secure water for irrigation and household use, and renewable energy for lighting their homes and powering small businesses. Rural women's cooperatives are providing childcare services for and by their members.
Yet, delivering on the gender equality commitments of the 2030 Agenda stands or falls by the allocation of sufficient resources for their achievement and concerted action by governments and all stakeholders. Essential services on which millions of rural women and girls depend—health, education, childcare, shelters—are chronically underfunded or simply unavailable. Where they exist, they are often the first to be hit by austerity measures, which are once again on the rise. In 2018 alone, 124 countries are expected to be cutting their budgets, eroding social protection measures and essential services on which so many rural women and girls depend. This is not inevitable. In virtually all countries, there is scope for raising or reallocating resources to strengthen public services that are essential for women and girls. It is a matter of political will and of using all the available policy tools. The cost of inaction is simply too high.


text:
2023: Why I'll be disappointed If VP Osinbajo Runs For President - Analyst
More from Homepage Lagos
Tuesday, August 24th, 2021 12:31pm
By Olamide Fadoju
Public Analyst, Jimi Disu has said he will be disappointed if Vice-President, Yemi Osinbajo eventually declares to run for the presidency in 2023.
VP Osinbajo again on Monday denied rumours that he has declared to run for the highest seat in the land but Jimi Disu believes he is being clever with the truth.
Quizzed about his stand, Disu explains that this is likely a strategy and that signs are pointing towards Osinbajo declaring for Presidency eventually.
Watch further explanation below>>>>
Furniture and some non-sensitive materials recently delivered for the 2023 General Election have been destroyed in Anambra State.
The German Consulate in Istanbul would be closed on Wednesday due to a heightened threat of attack in Turkiye's biggest city, the German Foreign Ministry has said.
Sonia Ekweremadu, the 25-year-old daughter of Senator Ike Ekweremadu is unfit to stand trial, her lawyers told an Old Bailey court in London on Tuesday.
The House of Representatives has approved President Muhammadu Buhari's request to borrow N1 trillion from the Central Bank of Nigeria (CBN) to fund the 2022 supplementary budget.
The Rivers Debate Group has announced a change of date for the 2023 Rivers Governorship Debate.

redpajama_set_name: RedPajamaCommonCrawl


text:
Q: Redirect stderr to error handler Is it possible to pass a stderr message to an error handler function and have it decide how the message should be handled?
A quick example would be if a script that if the user gives foo.bar non-existent files to copy or only gives it one input parameters. Instead of printing the system error messages immediately, I want to print some additional information first. Also tee it into log.txt.
This is what I have thought of so far but it does not seem to work.
#foo.bar
function errhand
{
  read IN #read stdout which has stderr redirected.
  echo "an error occurred while copying." | tee -a log.txt
  echo $IN | tee -a log.txt
}

cp $1 $2 || errhand 2>&1   #redirect stder to stdout if error occurs.

A: You can redirect the standard error of the cp command to errhand, which can simply return if there is no text to output.
errhand () {
    read errormsg
    [[ -z $errormsg ]] && return
    { echo "an error occurred"
      echo "$IN"
    } | tee -a log.txt
}

cp "$1" "$2" 2> >(errhand)

redpajama_set_name: RedPajamaStackExchange


text:
Q: Weak equation of Euler Lagrange I'm a little bit confused with the weak equation of Euler-Lagrange since it looks to have severals form of weak equations.
Let $\Omega=(a,b)\subset \mathbb R$ and $f\in \mathcal C^0(\bar\Omega\times \mathbb R\times \mathbb R )$, $f=f(x,u,\xi)$. The differents weak for I have are:

*

*$$\int_a^b (f_u \varphi+f_\xi \varphi')=0,\quad \forall v\in \mathcal C_0^\infty (a,b).$$

*$$\int_a^b(f_u \varphi+f_\xi \varphi')=0,\quad \forall \varphi\in W_0^{1,p}(a,b).$$
So why in one case we take $\varphi\in \mathcal C_0^\infty (a,b)$ and in an other case $\varphi\in W_0^{1,p}(a,b)$. It's a little bit confusing for me.

A: The space $C_0^\infty(a,b)$ is dense in $W_0^{1,p}(a,b)$. Hence, (2) follows from (1) if the terms under the integral are regular enough.
(1) follows directly from (2) since $C_0^\infty(a,b) \subset W_0^{1,p}(a,b)$.


text:
Давид Рикардо или Дейвид Рикардо () е английски икономист, един от най-видните представители на зрелия класицизъм в икономическата наука, последовател и същевременно опонент на Адам Смит. Големи са неговите заслуги за утвърждаване на трудовата теория за стойността, която той твърдо отстоява. Основното му произведение е "За принципите на политическата икономия и данъчното облагане" (1817 г.).

Биография
Дейвид Рикардо произхожда от семейството на испански евреи, напуснало Испания заради репресии на верска основа и установило се, първо в Холандия, а после в Англия.

Основни идеи и възгледи
Давид Рикардо е привърженик на концепцията за икономически либерализъм, недопускащ никакво държавно вмешателство в икономиката и предполагащ свободно предприемачество и свободна търговия.

Основните положения в неговите теории:
 Главната задача на политическа икономика е да определи закони, управляващи разпределението на доходите ("продукта на земята", националния доход) между трите класи;
 Държавата не трябва да се намесва нито в производството, нито в размяната, нито в разпределението. Държавната политика трябва да е изградена на икономически принципи, а основният способ за взаимодействие на държавата с населението трябва да се свежда до данъчното облагане. Но данъците не трябва да са големи, тъй като ако голяма част от капитала се изземе от оборота, то резултатът ще е нищета на голяма част от населението, тъй като единственият източник на ръст на богатството е потреблението;
 Движеща сила на общественото развитие е личният интерес – обществото е съвкупност от "егоисти", които нямат други грижи освен личните си интереси и на тях им е чужд стремежът за общото благо и щастие.

Теория за разпределението на доходите

Според него съществуват три основни класи, едни от които движат общественото развитие – бизнес класата, чиито членове осъществяват промишлената революция, земевладелците и работници и съответстващите им три вида доходи:
 земевладелци – рента;
 собствениците на парите и капитала, необходим за обработката на тази земя – печалба;
 работници, обработващи земята – заплата.

Заслугата на Рикардо е, че изследва количествените закономерности и зависимостта между трите вида доход.

Рентата за него е онзи дял от продукта на земята, който се плаща на земевладелеца, а източник на рентата – прилагания към земята труд. Тъй като обаче земята е ограничена, и в определен момент се налага обработката на второкачествени и по-неплодородни земи, стойността на селскостопанските продукти се определя от труда, вложен в най-некачествените земи. Тези земи не носят рента, а само средна печалба от вложения труд. В по-плодородните участъци се стига до печалба над средната, като тази добавъчна печалба се присвоява от собствениците на по-плодородните земи. Изводът е, че рентата представлява разликата между издръжките на производството в най-лошокачествените участъци (определящи естествената цена) и по-плодородните участъци земя.

Печалбата според Рикардо е най-важната мотивация за движението и натрупването на капитала и икономическото развитие.

Рикардо разглежда трудът като стока, а работната заплата е цената на труда. Според него тя зависи от една страна от предлагането и търсенето на работници, а от друга от цената на стоките, за които се изразходва работната заплата. Т.нар. естествена цена на труда е онази цена, която е необходима за да даде възможност на работниците да съществуват и да продължават рода си без техния брой да се променя. Така растежът на населението води до превишаване на предлагането над търсенето, което предизвиква падане на цената на труда под неговата естествена стойност, и обратното.

Според Рикардо пазарната цена на труда винаги се колебае около неговата естествена цена.

Теория за стойността
Основен принцип на разменната стойност: Заключеният в стоката труд определя нейната разменност.

Рикардо създава единна трудова теория за стойността. Според него за стойността на стоките следва да се отчита не само трудът за производството на дадена стока, но и овеществения труд (трудът, изразходван за оръдията, инструментите и сградите, включени в процеса на производство на дадения продукт). Рикардо е първият, който разграничава новосъздадената стойност от пренесената върху стойността на продукта вече съществуваща стойност (за производство).

Грешка на Рикардо е, че смята, че капиталът не създава стойност, а неговата стойност само се пренася върху стойността на продукта, който е създаден с помощта на този капитал.

Рикардо разграничава потребителна стойност и разменна стойност на стоките и съзнава, че полезността на стоките не може да служи за мярка на тяхната разменна стойност. Примерно водата и въздухът, които притежават изключителна полезност за човека, са с нищожна разменяемост, обратното е при златото и среброто.

Стоката, произведена с голяма трудност, винаги струва повече отколкото стока, произведена с по-голяма лекота, даже ако всички хора мислят, че тя е по-полезна от първата. (За разлика от Жан-Батист Сей, който счита че полезността е регулатор на стойността.)

Рикардо смята, че стойността на някои редки стоки се отличава от разбирането за стойността на масовите стоки и тя се определя не от труда вложен за тяхното производство, а от тяхната рядкост или оскъдност. Към тази група причислява редки статуи, картини, монети, вина, антики. Количеството на такива стоки не може да се увеличи с никакъв труд. Тези стоки винаги имат висока стойност.

Теория за сравнителните предимства
По отношение на външната търговия Рикардо е привърженик на икономическия либерализъм и е за пълна свобода на външната търговия. Външната търговия според него трябва да се основава на международно географско разделение на труда. Страните трябва да се специализират в производството на дадени стоки според своите ресурси и условия.

Понижаването на цените води до засилване на износа. Търговският баланс постепенно се превръща от пасивен в активен. Ако търговията е свободна, то пасивният търговски баланс не може да се задържи дълго в една страна. При свободна международна обмяна не може да има нито излишно, нито достатъчно количество пари.

Библиография
 The High Price of Bullion, a Proof of the Depreciation of Bank Notes (1810)
 Essay on the Influence of a Low Price of Corn on the Profits of Stock (1815)
 On the Principles of Political Economy and Taxation (1817)

Източници

Външни препратки

Английски икономисти
Английски бизнесмени
Икономисти от класическата школа
Класически либерализъм
Евреи във Великобритания
Сефарадски евреи
Родени в Лондон

redpajama_set_name: RedPajamaWikipedia


text:
Gaius Catellius Celer (also known as Lucius Pompeius Vopiscus Gaius Catellius Celer) was a Roman senator who flourished during the Flavian dynasty. He served as suffect consul for the nundinium September-October 77 with Marcus Arruntius Aquila as his colleague.

Name
The nomen "Catellius" is rare. Ronald Syme could only find it represented in three cities: Aesernia (modern Isernia), Forum Sempronii (modern Fossombrone), and Volsinii, where four freedmen of a Lucius Catellius are attested. Syme has narrowed the choice between these: a fragmentary name "Q. Pompeius [...] Cat[...]" attested at Volsinii, points to Volsinii as his home town.

At times Celer also included the nomen "Arruntius" in his name, indicating either that his mother belonged to that family, or he received a legacy from someone of that family in return for adopting that person's name, a practice referred to by scholars as "testamentary adoption". Further, no later than AD 80 Celer adopted the longer version of his name -- Lucius Pompeius Vopiscus Catellius Celer -- suggesting he accepted another testamentary adoption around that time, in this case from one Lucius Pompeius Vopiscus. This Pompeius Vopiscus might be the suffect consul of 69.

Career
Details of Celer's life are lacking before 20 May 75, when he first appears in the records of the Arval Brethren as a member of that college. Syme argues that between that date and October 77, when he is mentioned again, he was away from Rome, serving as governor of Lusitania. He returned to Rome to serve as suffect consul in 77, and attended all the known ceremonies of the Arval Brethren until 86, and does not appear again until 27 May 90. Syme explains his absence by dating Celer's term as juridicus of Tarraconensis to these years. Prior to serving as juridicus, Celer is known to have served as curator operum publicorum, succeeding Marcus Hirrius Fronto Neratius Pansa.

In AD 91, when he was eligible to participate in the sortition for the proconsulate of either Africa or Asia, he failed to obtain either one.

Family
Some authorities raise the possibility that Pompeia Celerina, the mother of Pliny the Younger's second wife, was Celer's daughter. In his monograph on Imperial Roman nomenclature, Olli Salomies points out that if this were the case, she had to be born after Celer accepted the testamentary adoption from Pompeius Vopiscus -- after 80 -- but "a lady born at the earliest in c. 80 cannot have been the mother of Pliny's second wife."

References

1st-century Romans
Senators of the Roman Empire
Suffect consuls of Imperial Rome
Roman governors of Lusitania
Vopiscus Gaius Arruntius Catellius Celer
Ancient Roman adoptees


text:
Q: Android - findViewById returns null I'm following an example from a book and I can't understand why findViewById returns null.
This is my activity:
package it.mt.compass;

import android.app.Activity;
import android.os.Bundle;
import android.widget.Toast;

public class CompassActivity extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.main);

        CompassView cv = (CompassView)this.findViewById(R.id.compassView1);

        // this crashes the application
        //cv.setBearing(45);

        // some debug code
        Toast test_result;

        if(cv == null) {
            test_result = Toast.makeText(this, "1", Toast.LENGTH_SHORT);
            test_result.show();
        }
        else {
            test_result = Toast.makeText(this, "0", Toast.LENGTH_SHORT);
            test_result.show();
        }

        // it shows 1
    }
}

and this is the res/layout/main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <it.mt.compass.CompassView
        android:id="@+id/compassView1"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
    />
</LinearLayout>

Already cleaned (as suggested in other similar topics; what does "Clean" do?) the project with no luck.
Many thanks in advance.
Mirko
As requested, the constructors' code:
// Constructors

public CompassView(Context context) {
        super(context);
        initCompassView();
    }

    public CompassView(Context context, AttributeSet attrs) {
        super(context);
        initCompassView();
    }

    public CompassView(Context context, AttributeSet ats, int defaultStyle) {
        super(context);
        initCompassView();
    }

That's the correct version (the problem was I didn't passed the parameters correctly to the superclass constructor):
// Constructors

public CompassView(Context context) {
        super(context);
        initCompassView();
    }

    public CompassView(Context context, AttributeSet attrs) {
        super(context, attrs);
        initCompassView();
    }

    public CompassView(Context context, AttributeSet ats, int defaultStyle) {
        super(context, ats, defaultStyle);
        initCompassView();
    }

A: CompassView constructor implementation is incorrect. You're not passing the attributes to superclass and hence the id is lost.
Change here the superclass constructor invocation
public CompassView(Context context, AttributeSet attrs) {
    super(context);

to super(context, attrs);
and
public CompassView(Context context, AttributeSet ats, int defaultStyle) {
    super(context);

to super(context, attrs, defaultStyle); if the superclass has a ctor that accepts three args. Otherwise just use super(context, attrs). Oh, and rename the arg name from ats, even though the name doesn't matter.

A: In eclipse do:

*

*Projects -> Clean.

*Eefresh your app.

*Run.

this will clear generated old R class.

A: I would try closing eclipse completely and then open it again.  I've seen some really bizarre things like this happening.  Another way you can try this is to just add a "textView" and try to do a findById on that and see if it's returning null.  You could be loading the wrong xml view..
ie: your are loading a layout from one directory but it's actually loading a different view in a different directory with the same name...

A: add import it.mt.compass.R;
and try another View, like a Image or TextView instead


text:
← Cassandra Carr on the Hot Seat
Action before Reaction →
Kay Springsteen is in the Hot Seat
I have Kay Springsteen author of Lifeline Echoes in the hot seat.
Janice: Tell us about yourself?
Kay: I grew up in Michigan but transplanted to the south about 10 years ago and now reside in the shadow of the Blue Ridge Mountains in Virginia with my five small dogs and two bigger ones. Two of my four children live nearby, a married son who has a daughter of his own, and one of my twins. The other twin lives just outside of USMC Camp Lejeune in North Carolina. My oldest daughter still resides in Michigan. When I'm not writing, I transcribe and edit medical reports. Besides being an avid reader, my hobbies include photography, gardening, hiking and camping, and of course spending time with my terrific G-baby. I really am a firm believer in happily ever after endings and I believe there's one out there for everyone; it just may not be exactly what you expect or think you want.
Janice: When did you start writing?
Kay: I think from the time I could hold a pencil. I loved writing the essays for school and the book reports. I loved telling the classic back-to-school story of how I spend my summer vacation. I wrote stories off and on for years but I only began to seriously write while my kids were young, about 10 years ago. Then I put it on hold again, when I found myself a single mom. But last year I found myself living on my own, kids all out in the world, and unemployed from my medical transcription job. While I looked for a new job, I started writing. I was introduced to a wonderful friend, who became a writing mentor and a most awesome crit partner, mystery author J. Gunnar Grey. J. Gunnar is Mr. Han (Jackie Chan) to my Dre Parker (Jaden Smith) from the Karate Kid 2010. Everything I wrote before J. took me on as a crit partner was lacking. The embers of the stories were there but the flames, the ability to present them wasn't polished.
Janice: Who was the biggest influence on your writing?
Kay: Other than my crit partner, I would have to say my mom was a great influence because she got me interested in books and in reading, and she used to tell stories off the top of her head when I was small. My dad used to love everything I wrote, which of course encouraged me tremendously. In terms of authors, it was all things romance for a while, then on to science fiction, back to romance, into mystery. I was, and still am, a voracious reader. So there isn't one single influence.
Janice: It sounds like you have two very supportive parents. How do you go about your writing? Do your prefer pencils to pens or is it all straight computer work?
Kay: It's all about the computer. I type over 100 wpm, not quite as fast as I think but close, and someone who types for a living thinks in terms of letters instead of words. It's easier to work on the computer for me. I do carry a notebook to jot ideas when not near the computer, but the stories themselves pop out on the computer.
Janice: What influences you in your writing?
Kay: Music, movies, reading, or straight research? A combination of all these things. I make sound tracks for my stories and have certain theme songs for the characters and the moments. When writing the scenes, a song might be put on repeat on the MP3 player until the scene is finished. But movies and TV are a huge part of my life also, not for the story lines but because I watch the actions of the actors during various scenes, and as I'm watching them, I think in terms of how I would write the description. It helps me keep the action beats going in a story when, for instance, I pay attention to how two cops in a car all day chat back and forth, what they talk about not being nearly as important as their tiniest idiosyncratic actions that can be described. And as far as research, the nature of my day job is research, so that comes naturally to me. I like my stories to be as authentic as I can make them, so when I wrote a blind character, I researched all things to do with blindness. For Lifeline Echoes, it was things like rock climbing, or the things firefighters and dispatchers did 10 years ago. I talk to people, research on line, go to the library. Pretty much whatever it takes to learn enough to be comfortable in writing what I need to write.
Janice: When do you write morning or evening, or are you a late into the wee hours of the morning person?
Kay: My best stuff seems to come just before I start my job, so it often has to be put on hold for 6-7 hours. But when I stop working at 11 p.m., it's usually had time to steep and when I'm ready after work, it just spills out. I might write until 4 a.m. on those nights.
Janice: Who's in charge you or your muse?
Kay: It's a combination. I have an ability to write in my head and maintain the integrity of the story until I get to the computer. So if I'm on the road driving and the muse wants to work, we put on some music and go for it. Then when I can get to the computer, again, it all spills out.
Janice: That's a very good talent to have. Use only one word to describe your writing style?
Kay: Descriptive. Or at least what you want your readers to take away from your writing. My vibe. That is, the vibration from the creative strings I'm plucking when I put words together.
Janice: What other books have you written?
Kay: My debut novel was a digital publication released March 1, 2011, called Heartsight, the story of a U.S. Marine who had been blinded in battle, and was more or less hiding out in his house on a secluded beach…until a divorced woman and her daughter with Down syndrome arrived and shook up his world.
Janice: That sounds like a wonderful story. What influenced your recent book, the one you are promoting here today?
Kay: Lifeline Echoes came about as the result of a challenge between myself and my crit partners. Originally, we were supposed to write a Harlequin-length novel – we were to choose a line from Harlequin and research the requirements. I thought perhaps a suspense. But I didn't have a clue what to write, and I was sitting at my desk with my MP3 player on wondering about it, when Garth Brooks came on, When You Come Back To Me Again (it's from the movie FrequencyI ). Basically, the song is about someone who's in trouble and he finds hope in knowing someone's out there who still believes in him. The chorus goes "On a prayer, in a song, I hear your voice and it keeps me hanging on…" That was my premise. A voice lifeline and falling in love with just the voice. It morphed a little from the original thought, since I was torn between a military theme and a firefighter theme. I considered using a September 11 story but really wanted this to be my own and didn't want to steal from the importance of that day. So I moved the story to the West Coast, created an earthquake, and stuck a firefighter under a building and a dispatcher in the office, who would try to give him the will to live until help could get there. As soon as I set that in place, the story took off on its own. I had the first 90K draft written in under three months, way more than a Harlequen but it didn't matter. My main crit partner told me it was a winner, with the right amount of tears, laughter, and suspense. And if you ever read any of J. Gunnar Grey's stuff, you'll understand why I found hearing those things very uplifting. My editor told me she stayed up all night reading my submission; she couldn't put it down. When people say those things, I know I've done something right.
Contest: I would love to give a free PDF copy of Lifeline Echoes to one of your commenters by drawing.
Buy link: http://www.astraeapress.com/#ecwid:category=662253&mode=product&product=3465733
Voices form a powerful connection. The day the earth rocked LA, Sandy Wheaton became a voice lifeline over the radio for trapped firefighter, "Mick." Less than twenty four hours later, she had fallen in love with him. Shattered when she learned that rescue came too late, she sought solace Wyoming, the home state he had loved. Now, seven years later, she's made a life there as the owner of a popular local bar. But her wounds are still fresh, and she longs to let go of the past and her lost love so she can begin living again. That opportunity presents itself when the local prodigal son returns home. The attraction between them is instant. It feels like she's known him far longer than just a few days.
Sixteen years ago, Ryan McGee left home in the midst of controversy. After living through a harrowing trauma, he finally returns home when his family needs his help through some troubling times. All he wants to do is make amends with those he hurt most and to get back to the life he'd never wanted to leave in the first place. When he meets the sexy bartender, he starts thinking in terms of forever. But there's still someone out there he wants to find, someone who once believed in him and gave him hope.
The job was all that mattered now. Sandy made herself disregard the toppled shelves and scattered books. She blocked out all thoughts about the likely state of her own home. As she listened to the chatter on the official channels, she kept meticulous handwritten notes regarding the status of each unit checking in.
"Battalion 9 Alpha, this is Engine Squad 9-¬Bravo, do you copy?" The connection was filled with static and the voice was muffled, hard to hear.
Sandy waited for the response of the battalion chief on scene. None came.The callout was repeated, the voice sounding a bit more urgent.
"This is L.A. Engine Squad 9-Bravo, dispatched to the Convention Center—" Again static broke the transmission.Following protocol, after the second unanswered call, Sandy intervened. "Copy you, ES-9-Bravo. This is central dispatch. Your transmission is breaking up."
The response was drowned out by a loud burst of static in the earpiece.
"Nine-Bravo, be advised you're breaking up," she repeated.
More harsh squawks of static burst from the receiver. Sandy winced, feeling like her head might explode. Then, amid the static, she clearly heard the code every dispatcher dreaded.
"Nine-Bravo is 10-¬60, this location. Code three, code three, code three . . . trapped. . ."
The code for imminent danger!
Static filled the airwaves again as Sandy punched buttons on her console, frantically trying to boost the signal."Dispatch, are you there?" The voice was screaming. "Central! This is 9-¬Bravo in need of assist. The building's coming down around us!"
Afraid to switch over to relay, with the risk of losing contact altogether, she motioned to Ellen, the dispatcher sitting next to her.
Quickly, Sandy wrote on her notepad in bold black ink: UNIT IN TROUBLE.
At the next desk, Ellen nodded and switched channels to contact the Battalion 9 squad leader over the comm.
"Nine-Bravo, this is Central Dispatch," Sandy acknowledged. Only with great effort did she prevent her stomach-wrenching fear from leaking into her voice. Dread shot out little tentacles of hopelessness to curl around her lungs, squeezing the breath out of her. "I'm reading you, sending help your way. What's your location?"
"Civic Center parking garage—A level. The building's coming apart! We need extraction." The voice was still urgent but now without the panic.
She had to get her own panic under control and keep it that way, Sandy reminded herself, or she couldn't help anyone."Copy you, 9-¬Bravo. Who am I speaking with?"
"Mick-" More static, then, "Mic-key."
Sandy scribbled everything she could make out into her hand-¬written notes. "Mickey, you're breaking up very badly. How many do you number? How long have you been trapped?"`
"Two confirmed, dispatch, possibly three. I can feel my partner.He's not moving. I heard someone else moaning down here earlier. I don't know how long it's been. I think I've been unconscious—I'm pinned—can't move. It's dark—can't see a thing."
Sandy passed off the information to Ellen so her coworker could convey it to the battalion chief. The sarcastic part of Sandy's mind registered the irony of having crossed into the twenty-first century and being reduced to the mockery of a child's game of telephone.
With a pointed shake of her head, Ellen caught Sandy's eye and handed her a message from the battalion chief. As she read, Sandy's heart fluttered in her chest briefly before moving upward to stick in her throat.
Her free hand came up of its own volition to cover her mouth, as if to prevent herself from saying the words she was reading. Her stomach threatened to pitch up her breakfast.
The Convention Center had collapsed with several men inside.Some of them were buried under four floors of rubble, while above them, the fire from the gas main explosion burned fully involved and uncontained. Rescue efforts would be delayed and prospects for extraction were grim. A chaplain was en route.
God help them all! How could she tell someone he wasn't going to be rescued? What could she say to a man when her words were likely to be the last he'd ever hear?
By Janice Seagraves, author • Posted in Uncategorized	• Tagged Kay Springsteen, Lifeline Echos
4 comments on "Kay Springsteen is in the Hot Seat"
J. Gunnar Grey
I keep telling ya, Kay, it's more like Mallory to your Miller, from the movie "Force Ten from Navarone." You were primed and ready to explode with some of the best stories I've ever read. All you needed was a blasting cap under your seat.
Felicia Rogers
This is the most interesting blurb I've read in a long time. I can't wait to read it!
Shannon J.
Love the cover of this book! Sounds like a great story!!
Thank you for the interview and giveaway!!
shannonjean14(at)gmail(dot)com
Cindy Rogers
Enjoyed the interview and want to enter the giveaway.
robseanmom at gmail dot com


text:
Current Search: doctoral thesis (x)
(201 - 250 of 607,166)
"Nockes" Under bridge at Carabelle Post Elena.
Florida State University. Department of Oceanography
FSU_HUA_2009012_B04_F11_I012
"Now I Ain't Sayin' She's a Gold Digger": African American Femininities in Rap Music Lyrics.
Pemberton, Jennifer M., Martin, Patricia Yancey, Moore, Dennis, Quadagno, Jill, Padavic, Irene, Department of Sociology, Florida State University
This dissertation reports the results of a study about representations of (Black) women, sexuality, and gender relations in rap music lyrics. I explore the extent to which rap music lyrics reproduce or challenge gendered, racialized, and sexual stereotypes of African American women. I ask how men rappers differ from women rappers in depicting (Black) women and themselves. I show what qualities or practices, particularly sexual qualities and practices, are considered as feminine or womanly in...
Show moreThis dissertation reports the results of a study about representations of (Black) women, sexuality, and gender relations in rap music lyrics. I explore the extent to which rap music lyrics reproduce or challenge gendered, racialized, and sexual stereotypes of African American women. I ask how men rappers differ from women rappers in depicting (Black) women and themselves. I show what qualities or practices, particularly sexual qualities and practices, are considered as feminine or womanly in rap music and hip-hop culture and how these qualities and practices are similar to or differ from mainstream gender hegemony. I examine whether and how rap music lyrics construct a hierarchical and complementary relationship between (Black) masculinity and femininity. I ask which feminine meanings and practices are treated as "pariah femininities" and point to features of hegemonic masculinity in hip-hop culture and the broader African American community. Finally, I ask whether and how gendering practices represented in rap music lyrics constitute resistant femininities and challenge White and middle-class gender hegemony. I created a database of rap songs on platinum albums with an original release date of 1984 through 2000. I randomly selected 450 songs from the sampling frame for content analysis. In general, I find that rap music both reproduces and contests prevailing gender, race, class and sexual ideologies and social structures. My analysis of rap lyrics suggests that many male rappers depict (Black) women as promiscuous sexual "freaks" and "bitches" who have sex with men for money and/or other material goods. In many lyrics, they describe their desire for and engagement in sexual activities with freaks and bitches, but they do not express respect. Some women rappers reproduce gendered and racialized stereotypes in their lyrics as well. Still, other women and men rappers challenge these negative images in their songs and offer alternatives. Instead of calling for a reserved or muted sexuality for African American women, a few women rappers depict themselves and other Black women in lyrics as sexually free, in control of their sexuality, and financially independent from men.
"O, you're so sweet! And those beautiful eyes! By that tricky cook I was hypnotized.".
"Odd and Even Dolls".
"Odd Fountain".
"Oh My!".
"Oh! Go On!!".
"Oh! Hellen".
"Oh! You musn't, Mr. Brown. If the madam should see, What in the world would become of me?".
"Oh, you wretch! this I shall not endure. I shall fire that flirt and a divorce procure.".
THE "OLD SUMPTER HERO": A BIOGRAPHY OF MAJOR-GENERAL ABNER DOUBLEDAY.
RAMSEY, DAVID MORGAN., The Florida State University
Abner Doubleday was an unusual and often a controversial person. Born into a family staunchly supporting Andrew Jackson, Doubleday reflected the determined Unionist position of the strong-willed president. Abner's attitude towards the Union was later vividly demonstrated at Fort Sumter. A mediocre career at West Point illustrated Doubleday's lack of desire to excel although he possessed the ability to do so. The controversy over the origin of baseball, although Doubleday was never directly...
Show moreAbner Doubleday was an unusual and often a controversial person. Born into a family staunchly supporting Andrew Jackson, Doubleday reflected the determined Unionist position of the strong-willed president. Abner's attitude towards the Union was later vividly demonstrated at Fort Sumter. A mediocre career at West Point illustrated Doubleday's lack of desire to excel although he possessed the ability to do so. The controversy over the origin of baseball, although Doubleday was never directly involved in the question, was the first of several controversies with which Abner Doubleday's name is associated., Doubleday never seemed satisfied with his early life. In his papers he continually referred to people, prominent in later years, which he knew. While serving in the Mexican War, Doubleday continually felt the need to relate the dangerous situations in which he was placed. He seemed to want to demonstrate his personal responsibilities, which while actually meager, he viewed as of supreme importance. Doubleday apparently wanted to be a famous, bold cavalier, but realized he failed to accomplish his objective and stressed his "noble" deeds., Doubleday loved large cities and the benefits they offered a person. He liked being in the right social circles and enjoyed the "good life." By 1852, while serving as a commissioner for the Senate, Doubleday had come to despise Mexico and the Mexicans. By 1858, while serving in Florida, he disliked the inconveniences of chasing "savages." With secession in 1860 Doubleday no longer liked Charlestonians; later extending his revulsion to all Confederates., With the crisis at Sumter in 1861 Doubleday was greatly troubled. The affront to the United States government was almost more than he could bear. With the outbreak of the war, Doubleday was more than willing to fight the rebels. A dependable, if unspectacular soldier, Doubleday served well during the Civil War. While no one accused him of original thinking militarily, his men always fought well. Gettysburg was Doubleday's finest hour but became his final hour in the Civil War when he could not countenance serving under a junior officer., It seems strange that Doubleday served in the Freedmen's Bureau since his superior was none other than his old enemy from Gettysburg, O.O. Howard. Doubleday's service in California brought the controversy over the origin of the cable car. Retirement from the army in 1873 brought out several new qualities in Abner Doubleday. He wrote books, read French and Spanish literature, and became interested in the occult and became a believer in theosophy., Doubleday was a colorful figure in nineteenth century America. He was associated with several significant events in the growth of the nation. Doubleday represented, possibly to an extreme, the attitude of many American Unionists and supporters of Manifest Destiny. His commitment to a united nation is similar to Lincoln's attitude. Doubleday not only vocalized this sentiment, but, like Lincoln, was prepared to fight for his belief. Abner Doubleday was an intense American. He desired a strong, powerful United States and opposed those not supporting such a course.
"On A Fragrant Piny Hill".
"On a Fullbright in Japan".
FSU Dept. of History, Phi Alpha Theta, Delta Chapter
"On A Sunny Saturday".
"On the Road to Somewhere".
"On With the Show".
"One for All and All for One": Assessing the Implementation of One Comprehensive School-Wide Discipline Program in a Primary School in Southwest Georgia.
Ward, Linda T., Beckham, Joseph, Jakubowski, Elizabeth, Irvin, Judith, Guthrie, Kathy, Department of Educational Leadership and Policy Studies, Florida State University
In schools across America, school safety and student discipline remain primary concerns for all stakeholders in the education process. Researchers and educators suggest that implementing a school-wide discipline plan tailored to meet the needs of a particular school setting is one solution to the complex behavior management problem. The limited research on the actual impact of using a school-wide discipline program in specific school settings indicates that further investigation regarding...
Show moreIn schools across America, school safety and student discipline remain primary concerns for all stakeholders in the education process. Researchers and educators suggest that implementing a school-wide discipline plan tailored to meet the needs of a particular school setting is one solution to the complex behavior management problem. The limited research on the actual impact of using a school-wide discipline program in specific school settings indicates that further investigation regarding these programs is warranted. The primary purpose of this longitudinal study was to gain insights and understandings of the implementation of a comprehensive behavior management program, Discipline with Unity, within a specific primary school setting in Southwest Georgia across a three-year time frame, 2005-2008. The goal was to assess the impact of program implementation on (a) student behavior, (b) teachers' perceptions toward behavior management, and (c) school climate. Revelatory themes emerging from teachers' narrative comments along with consequences, both intended and unintended, of program implementation were also identified and discussed. Furthering research in this area should add information to the existing body of knowledge regarding the process of developing and implementing a positive school-wide discipline initiative oriented toward preventing behavior problems. However, the results of this study may not be generalized to other settings. The descriptive case study utilized a mixed methods non-experimental research design with an emphasis on qualitative approaches to data analysis. In-depth interviews and focus group discussions were the primary sources of data collection and allowed the researcher to gain access to more descriptive information while providing insight into teachers' perspectives of program implementation. Qualitative data analysis techniques were used to derive themes and understandings of the behavior initiative. Details of a story emerged throughout the guided inquiry process to describe program implementation as perceived by school staff. Quantitative data were collected through office discipline referral data, school-administered discipline surveys, and district-administered Correlates of Effective Schools Staff Perception Surveys. Descriptive statistics, frequency distributions, independent t tests, and one-way between groups analysis of variance (ANOVA) were performed to help analyze and evaluate the school-wide program's impact. A variety of factors appear to have influenced the implementation of the comprehensive Discipline with Unity behavior management program. Results of the investigation indicated that this school-wide initiative brought about a number of changes in beliefs, teaching approaches, and discipline. Findings also suggested that implementation of the school-wide program had a generally positive impact on student behavior, teachers' perceptions of behavior management, and school climate. However, concerns regarding program implementation were also identified. Several of the prominent themes related to the outcomes of the study were the chronic offender, consistency in program implementation, and resistance to change. Specifically, recommendations were offered for the school-level educational practitioners implementing the program, district-level personnel, and future researchers in the process of school-wide behavior management program implementation.
"One Must Actually Take Facts as They Are": Information Value and Information Behavior in the Miss Marple Novels.
Kazmer, Michelle M.
One perspective not often brought to the study of detective fiction is that from the field of information science. Among other topics, information science is concerned with information behavior, or how people behave with respect to information: needing, seeking, accidentally encountering, avoiding, evaluating, storing and so forth. Examining the solving of a mystery as an information behavior has potential for insights into the genre and into our twenty-first century readings of detective...
Show moreOne perspective not often brought to the study of detective fiction is that from the field of information science. Among other topics, information science is concerned with information behavior, or how people behave with respect to information: needing, seeking, accidentally encountering, avoiding, evaluating, storing and so forth. Examining the solving of a mystery as an information behavior has potential for insights into the genre and into our twenty-first century readings of detective fiction. Current audiences are accustomed to modern information technology and the information behaviors afforded by it: amateur sleuths hack computer systems or professional detectives analyze trace evidence for DNA. Highly technologized contemporary information environments leave us to ask: in what ways do the manipulation of information value, and the sophistication of the information behaviors, in novels written by Agatha Christie in the early- to mid-twentieth century, continue to enthrall readers in the twenty-first?
"Our Abode".
O'Brien, Everett Melvin
The home where the occupying soldiers stayed while in Nordhausen.
FSU_EMO1998_0011_B01_F07_I012
"Our Director" Herb Reinhart.
"Our Italian Officer Who Visited Us at F.S.C.".
"Our Sweet Old Room at the Annex".
"Out of This World" (November 3-8, 1952).
"Over the Stile".
"P.S." regarding genealogy.
FSU_MSS0204_B02_F15_17
"Pals Three".
"Panorama de Paris", Le Pont-Neuf, les quais, les bains "A la Samaritaine".
Ancienne Maison Martinet
Very Nice Clean lettering on the signage for the baths
"Parallel Lines Never Intersect": The Influence of Dutch Reformed Presuppostitionalism in American Christian Fundamentalism "Parallel Lines Never Intersect":.
Brasich, Adam S., Corrigan, John, Porterfield, Amanda, Kelsay, John, Department of Religion, Florida State University
Much of the current historiography of American Christian fundamentalism focuses solely on Scottish Common Sense Realism as an intellectual source of fundamentalist epistemology since the early twentieth century. This thesis argues against this historiographical trend by illuminating the central role of Dutch Reformed presuppositionalism in the formation of fundamentalist epistemologies. Articulated within the context of revitalization, confessional, and secessionists movements within the...
Show moreMuch of the current historiography of American Christian fundamentalism focuses solely on Scottish Common Sense Realism as an intellectual source of fundamentalist epistemology since the early twentieth century. This thesis argues against this historiographical trend by illuminating the central role of Dutch Reformed presuppositionalism in the formation of fundamentalist epistemologies. Articulated within the context of revitalization, confessional, and secessionists movements within the state Dutch Reformed Church, theologians such as Abraham Kuyper and Herman Bavinck developed an epistemological system that stressed the necessity of correct presuppositions as a prerequisite for obtaining truth. Without correct ideas about God, in other words, one was incapable of perceiving any other truth in its fullness. This epistemological tradition was brought to North America by Dutch Reformed immigrants, who primarily settled in the Upper Midwest during the late nineteenth and early twentieth centuries. Cornelius Van Til, one of these immigrants, served as a professor at J. Gresham Machen's Westminster Theological Seminary immediately following the Fundamentalist-Modernist Controversy and taught his unswerving presuppositionalism to several generations of non-Dutch, American Presbyterian seminarians, including Francis A. Schaeffer. Schaeffer, though rejecting the strictly Reformed strain of fundamentalism represented by Machen and Van Til's Orthodox Presbyterian Church, adapted presuppositionalism to suit his purposes, combining it with traditional Princetonian Scottish Common Sense Realism. This resulted in an epistemology that proved to be influential during the rise of the Christian Right in the latter half of the twentieth century. By investigating epistemologies that competed with Scottish Common Sense Realism or creatively interacted with it, a clearer picture appears of the diverse nature of Christian fundamentalism. It no longer seems to be monolithic, but rather it contains a plethora of theological and confessional influences that interact in numerous ways that necessitate academic investigation.
"Parky," Mary Tarver, "Jartha," "Ruthie," and Dora Mandon.
"Patrick O'Donnell D.D.".
The "Peculiar Children" of the Nation: American Civil Religion at Antebellum West Point.
Graziano, Michael, Porterfield, Amanda, Corrigan, John, Koehlinger, Amy, Department of Religion, Florida State University
This thesis examines the history of antebellum West Point, tracing connections between the religious atmosphere of the Academy and the political ideology which it inculcated into cadets. A central claim of this essay is that the Revival of 1826 cemented a distinctly religious rhetoric as the operating ideology of West Point. This ideology held that the defense and maintenance of the sovereignty of the United States was to be cadets' primary objective. Cadets were taught that defending...
Show moreThis thesis examines the history of antebellum West Point, tracing connections between the religious atmosphere of the Academy and the political ideology which it inculcated into cadets. A central claim of this essay is that the Revival of 1826 cemented a distinctly religious rhetoric as the operating ideology of West Point. This ideology held that the defense and maintenance of the sovereignty of the United States was to be cadets' primary objective. Cadets were taught that defending American sovereignty constituted a divine mandate incumbent upon them as students of West Point. Finally, a key goal of this essay has been to ground "civil religion" in sources particular to this essay in the hope of reworking the concept for broader use in American religious history.
"Pete".
"Philpot".
"Picking Blackberries - Good? You Tell 'Em!".
"Pleasant Hours - Under the Magnolia".
"Poema Morale": An Edition from Cambridge, Trinity College B. 14. 52.
Thomas, Carla M., Treharne, Elaine, Emmerson, Richard, Warren, Nancy, Johnson, David, Department of English, Florida State University
This thesis is primarily focused on my modern edition and translation of "Poema Morale," a late twelfth-century English homiletic poem. Not since Richard Morris' great contribution to the study of early medieval literature has anyone produced a full translation of the poem from any of its seven manuscript variants. Because Morris worked 140 years ago when editorial and translation philosophies and practices were vastly different than twenty-first-century policies, a modern translation and...
Show moreThis thesis is primarily focused on my modern edition and translation of "Poema Morale," a late twelfth-century English homiletic poem. Not since Richard Morris' great contribution to the study of early medieval literature has anyone produced a full translation of the poem from any of its seven manuscript variants. Because Morris worked 140 years ago when editorial and translation philosophies and practices were vastly different than twenty-first-century policies, a modern translation and edition are necessary, especially for an introductory student in medieval literature. I begin my thesis with a four-part Introduction that covers the manuscripts in which "Poema Morale" is found; an analysis of Richard Morris' edition and translation for a better understanding of Victorian practices and the poem; an overview of the history of the homiletic tradition that led to the production of this poetic homily; and finally, a discussion of textual variance and how our perception and understanding of "variance" dictates our interpretation and editing of a text. Following the Introduction, I present my Editorial and Translation Policies so that the reader may understand why I made certain choices. My edition and translation follow the explanation of my policies and appear alongside one another. I include endnotes on the text for further explanation of certain editorial or translation decisions that I made. Finally, I include my diplomatic transcription in the Appendix so that the reader may see the manuscript through my eyes. Although first-hand experience with the manuscript can never be replaced, it is my hope that my diplomatic transcription will not only bring the reader closer to the manuscript but will also provide further insight into my editorial decisions. Having never undertaken such a tremendous task, I brought with me the beliefs I formed during my own beginning in the study of medieval literature. I began my medieval studies only two and a half years ago with a total of six courses, and my own frustrations with editions and translations led me to the desire to edit and translate the texts for myself. Through this thesis, I hope to present a modern edition and translation of a pivotal piece of early Middle English literature often forgotten in the medieval literary canon and, thus, the classroom.
"Policeman and Teddybear".
"Pop" Malone Reading a Newspaper.
Wells, L. Janet
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"Practise School".
"Prepare the Way...".
First Baptist Church of Tallahassee
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"Program of Chamber Music Featuring Ernst von Dohnanyi, Composer" (March 29, 1951).
"Psychology - and Dr. Hayden".
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