Needle Shape Research Articles

Sinc–Galerkin approach for thermal analysis of moving porous fin subject to nanoliquid flow with different shaped nanoparticles

In this article, for the first time, a powerful numerical approach, named Sinc–Galerkin algorithm, is employed to explore the thermal performance of moving porous fin subject to nanoliquid flow. Different configurations of‏ ‏nanoparticle such as needle, sphere and disk shapes are considered here. The nonlinear differential equation is introduced and nondimensionalized. The presented governing equation is a nonlinear two-point boundary value problem which has been reduced to a system of nonlinear equations by means of Sinc–Galerkin approach. In order to deal with the ordinary differential equations, the vector matrix from is obtained and then the Newton iteration method is performed. The numerical results are graphically shown for different system parameters, and the impact of shaped nanoparticles on the enhancement of thermal behavior of porous fins is addressed and discussed. It is found that the nanoparticle with sphere configuration has the best influence on the rate of heat flux compared to other shaped nanoparticles. Moreover, it is revealed that the effect of wet porous parameter is to enhance the thermal features of permeable fins.

Isolation of cellulose nanocrystals from different waste bio-mass collating their liquid crystal ordering with morphological exploration

Cellulose nanocrystals (CNCs) have been recognized as one of the most promising nanofillers in modern science and technology owing to their outstanding characteristics of renewability, biodegradability, excellent mechanical strength, and liquid crystalline behavior. Interestingly, these properties are dependent on their genetic and also on the isolation process. Therefore, this research aimed to unveil how the biological variations of cellulose can influence on the physical properties of the extracted CNCs. A standard optimized extraction process was adopted to isolate the CNCs from different sources. Extracted CNCs were compared through characterization tools, including Fourier Transformation Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Thermogravimetry Analysis (TGA), Dynamic Light Scattering (DLS), Field Emission Scanning Electron Microscopy (FE-SEM), Atomic Force Microscopy (AFM), and Polarized Optical Microscopy (POM). Different self-assembly patterns were observed for different CNCs, owing to their biological variations. The resultant nanocrystals displayed variable morphologies such as spherical, rod, and needle shape. The hydrodynamic diameter, crystallinity index, decomposition temperature, liquid crystallinity, and storage modulus were varied. Nanocrystals isolated from non-wood feedstock have shown a higher degree of polymerization of 108.2 and a high Crystllinity Index (C·I.) of 55.1%. The rod-like morphology with the liquid crystalline pattern was obtained at 3 wt% concentration for SCNC.

ИЗНОСОСТОЙКОСТЬ ЭПОКСИДНЫХ ПОКРЫТИЙ, НАПОЛНЕННЫХ СИНТЕТИЧЕСКИМ ВОЛЛАСТОНИТОМ НА ОСНОВЕ РИСОВОЙ ШЕЛУХИ

The extraction of natural wollastonite in the world is limited, so it is relevant to synthesize it on the basis of available calcium and silicon-containing raw materials, and it is promising to use rice husks as a source of silicon dioxide, as a waste of rice processing. Due to the needle shape of the particles, natural wollastonite increases the wear resistance of epoxy coatings, which arouses interest to study the influence of the phase composition and properties of synthetic wollastonite on this property. The calcium silicate synthesized by authors contains β-wollastonite, which is the target component. Its maximum content is achieved at a synthesis temperature not higher than 950 °C, approximately at the level of natural Mivall 10–97. Larnite is found as an impurity in the composition of synthetic wollastonite, it is an island silicate with a chain structure and therefore cannot provide such a modifying effect as fillers with anisodiametric particle shape. The nature of the particle size distribution curves of both natural and synthetic volastonite has two maxima, regardless of the filler synthesis temperature, with the exception of calcium silicate obtained at 900 °C, the particle distribution is narrower than in synthesized fillers, and they are smaller. The wear resistance of epoxy compositions, when filled with both natural and synthetic wollastonite, increases. The greatest increase in this indicator is achieved when using synthetic wollastonite, obtained at a ratio of calcium oxide and silicon dioxide 1: 1 and temperatures of 900-1000 °C. Thus, epoxy materials filled with both natural and synthetic wollastonium obtained at optimal ratios of the initial components and synthesis temperatures can be effectively and economically used as wear-resistant coatings.

Five-Year Results of a Prospective Multicenter Trial: AdVance XP for Postprostatectomy-Incontinence in Patients with Favorable Prognostic Factors

Objective: The aim of this study was to assess the security, value, and efficacy of the second-generation AdVance male sling XP (Boston Scientific®), after implementation in 2010 with advantageous modifications in the sling structure and needle shape, in a prospective multicenter long-term follow-up study. Methods: In total, 115 patients were included. Exclusion criteria were earlier incontinence (UI) surgery, nocturnal UI, former radiotherapy, or night-time incontinence. We also excluded patients with a functional urethra <1 cm in a preoperatively performed repositioning test. A consistent 24-h pad test, International Quality of Life (IQOL) score, visual analog pain scale (VAS), International Consultation-Incontinence Questionnaire (ICIQ-UI SF), International Index of Erectile Function (IIEF-5), International Prostate Symptom Score (IPSS), and Patient Global Impression of Improvement (PGI-I) scores were requested postoperatively. Results: The 24-month follow-up (114 patients) revealed 64.0% cured and 28.8% improved patients. Mean urine loss was reduced significantly to 19.0 g (p < 0.001). A mean PGI score of 1.5 and a mean VAS score of 0.2 were obtained. The 60-month follow-up (59 patients) revealed 57.6% cured and 25.4% improved patients. Mean urine loss was reduced significantly to 18.3 g (p < 0.001). A mean PGI score of 1.6 and a mean VAS score of 0.2 were obtained. Conclusions: The AdVance XP displays excellent continence results and secure effectiveness over a 5-year period. Moreover, these data are demonstrating low complication rates and improved quality of life in the long-term use of AdVance XP.

Two kinds of rare light chain cast nephropathy caused by multiple myeloma: case reports and literature review

BackgroundLight chain cast nephropathy (LCCN) is the most common renal disease caused by multiple myeloma (MM). In addition to ordinary light chain protein casts, there are a few rare casts with unique shapes, including light chain amyloid casts (LCAC) and light chain crystal casts (LCCC).Case presentationsHere, we report two patients. Patient 1 is a 72-year-old man who was clinically diagnosed with MM and acute kidney injury (AKI). Pathological examination of a renal biopsy revealed that there were many amyloid casts in the distal tubules that had a lightly-stained central area and a deeply-stained burr-like edge. The marginal zone of the cast was positive for Congo red staining and contained numerous amyloid fibers, as observed by electron microscopy. No systemic amyloidosis was found. The patient received 4 courses of bortezomib-based chemotherapy, and then, his MM achieved partial remission. Patient 2 is a 57-year-old man who was also clinically diagnosed with MM and AKI. Pathological examination of a renal biopsy showed that there were many crystalline casts in the distal tubules that were fully or partially composed of crystals with different shapes, including rhomboid, needle, triangle, rectangle and other geometric shapes. Congo red staining was negative. Crystals were also detected in the urine of this patient. After 9 courses of treatment with a bortezomib-based regimen, his MM obtained complete remission and his renal function returned to normal.ConclusionsLCAC and LCCC nephropathy caused by MM are two rare types of LCCN, and both have their own unique morphological manifestations. LCAC nephropathy may not be accompanied by systemic amyloidosis. The diagnosis of these two unique LCCNs must rely on renal biopsy pathology, and the discovery of urine crystals is of great significance for indicating LCCC nephropathy.

Anisotropic zero-resistance onset in organic superconductors

We study the coexistence of superconductivity (SC) and density-wave state and reconcile various puzzling experimental data in organic superconductors (TMTSF)$_{2}$PF$_{6}$ and (TMTSF)$_{2}$ClO$_{4}$. The anisotropic resistance drop above $T_c$ is qualitatively described by nascent isolated SC islands within a bulk analytical model. However, the observed anisotropic SC onset is explained only when the finite size and flat needle shape of samples is considered. Our results pave a way to estimate the volume fraction and the typical size of SC islands in far from the sample surface, and apply to many inhomogeneous superconductors, including high-$T_c$ cuprate or Fe-based ones.

Preparation, characterization and permeability evaluation of poly(vinylidene fluoride) composites with ZnO particles for flexible pipelines

Zinc oxide particles in needle shape were synthesized by hydrothermal route varying the reactor rotation speed (600, 1200, and 1800 rpm). The synthesized particles and commercial nanosized ZnO were characterized through X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), and scanning electronic microscopy (SEM), aiming to evaluate the influence of the synthesis variable on their thermal, morphological and chemical properties. In this study, the performance of composites comprising poly(vinylidene fluoride) (PVDF) matrix and ZnO synthesized particles, and commercial nanoparticles were compared. The composites were analyzed by XRD, TGA, FTIR, SEM, dynamic-mechanical analysis (DMA), and permeability to CO2. The results revealed that the particles synthesized even in micrometric diameter reduced the permeability much more than the commercial ZnO nanoparticles, therefore being more suitable for the application as inner pressure sheath in flexible ducts. Moreover, the ZnO needle-like particles with a lower dimension induced the PVDF β-phase to over 30%.

Slip and radiative flow of shape-dependent dusty nanofluid over a melting stretching sheet

The numerical analysis of dusty nanofluid stream, on a stretching sheet in the existence of thermal radiation along with melting heat and slip condition, is carried out. The influence of different shapes of nanoparticle on the enhancement of transfer of heat, Nusselt number as well as skin friction coefficient in the flow problem has been discussed. The momentum and thermal boundary equations are derived for the considered problem. The partial differential equations are converted to ordinary differential equations on applying similarity transformations. Furthermore, the equations are simplified by the Runge–Kutta–Fehlberg method. The parameter study has been performed using plotted graphs for nanoparticles of sphere, needle and disc shape.

Martensitic transformation in a α + β–Ti alloy after cryogenic treatment and its influencing to low elastic modulus biomaterials

The high strength titanium alloy is one of the most popular α + β-Ti type alloy and well responsive to the microstructure mainly depends on the processing history, heat treatment and selective faster cooling treatments. It has many engineering applications like military application, biomedical implant and aerospace application. The cryogenic treatment (CT) was typically done for faster cooling at low temperature (−20 to −100 °C) after solution treatment at 860 °C for 1 h then immediately quenched into liquid nitrogen bath with control manner. Subsequently, another identical sample quenched into the water to cool room temperature. After successfully solution treated both samples again preferred for ageing treatment at 500 °C for 5 h then air cooling. The examination of microstructures by SEM analysis revealed that after double steps heat treatment shows very fine α and β phases, with needle shape α are decomposed from α′ martensite tend to speed up by TiN or VN precipitates enhanced strength in the matrix. As well as, vanadium content is one of the important factors for martensite formation after solution treatment in the α + β phase field. The results show that after double steps heat treatment in CT obtained optimum mechanical properties such as 0.2% proof strength (PS) of 790 MPa, ultimate tensile strength (UTS) of 1200 MPa, strain (ε) of 70%, reduction area (RA) of 16.76%, and PS to UTS ratio of 0.66, respectively. To intuitive study estimate the effect in water quenching (WQ) as well as cryogenic treatment on microstructures and mechanical properties of high strength Ti-Al-V ternary alloy, which is potentially used in aerospace and structural applications owing to a high specific strength and high corrosion resistance. Meanwhile, after faster cooling in CT that martensite transformation tends to exhibit low elastic modulus for beneficial to orthopaedic implants in the human body.

Numerical simulation and experimentation of endodontic file using Taguchi DoE

The endodontic file is a tapered, needle shape body used for the preparation of curved human root canals. During the preparation, process files get failed due to the locking action offered by the canal wall. The present study aimed to find the fatigue life of endodontic files at 23°, 33° and 43° root canal curvature angles. Four brands of files were selected for the present study viz. Hyplex CM, Pro-Taper Next, Hero Shaper, Pro-File Vortex. The strain life analysis done using ANSYS showed that the Hyplex CM file gives the highest fatigue life at 23°, 33° and 43° root canal curvature angles. Therefore, Hyplex CM file was selected for DoE Taguchi Optimization study. Each experimental reading was conducted on X Smart Plus experimental setup under purely rotary and combined reciprocating-rotary motion, at 500 rpm, 600 rpm and 700 rpm and 23°, 33° and 43° root canal curvature angles. Hyplex CM file given maximum fatigue life at 23° root canal curvature angle and 500 rpm speed of rotation. But if file motion is combined rotary-reciprocating, life reduces. The ANNOVA study showed that P-value and significance F are very small, which represented that the regression model is effective.

Needle shape optical fiber measurement method introducing strain sensitivity matrix

Needle shape optical fiber measurement method introducing strain sensitivity matrix

The effect of chipping method on the geometry of particles produced from date palm frond

The aim of this research was to study the effect of chipping method on geometry of particles obtained from date palm frond as a lignocellulose residue. For this purpose, date palm fronds were chipped with four different equipment: chipper-flaker, chipper-hammer mill, flaker-hammer mill, and chipper-flaker-hammer mill. The geometry of the particle including particle size, particle size distribution, shape, and aspect ratio were investigated. The results showed that maximum weight percentage (more than 40%) was related to the particles sizes of +30/-40 mesh for all chipping methods and more than 50% of all generated particles had a needle shape. In the chipper-hammer mill method, both the weight percentage of useable particles in particleboard and the particle percentage of the rectangle or nearly rectangle particle were higher. Thus, the chipper-hammer mill method was judged to be the best method.

Goethite Nanorods: Synthesis and Investigation of the Size Effect on Their Orientation within a Magnetic Field by SAXS.

Goethite is a naturally anisotropic, antiferromagnetic iron oxide. Following its atomic structure, crystals grow into a fine needle shape that has interesting properties in a magnetic field. The needles align parallel to weak magnetic fields and perpendicular when subjected to high fields. We synthesized goethite nanorods with lengths between 200 nm and 650 nm in a two-step process. In a first step we synthesized precursor particles made of akaganeite (β-FeOOH) rods from iron(III)chloride. The precursors were then treated in a hydrothermal reactor under alkaline conditions with NaOH and polyvinylpyrrolidone (PVP) to form goethite needles. The aspect ratio was tunable between 8 and 15, based on the conditions during hydrothermal treatment. The orientation of these particles in a magnetic field was investigated by small angle X-ray scattering (SAXS). We observed that the field strength required to trigger a reorientation is dependent on the length and aspect ratio of the particles and could be shifted from 85 mT for the small particles to about 147 mT for the large particles. These particles could provide highly interesting magnetic properties to nanocomposites, that could then be used for sensing applications or membranes.

Anomalous sensitivity related to crystal characteristics of 2,6-diamino-3,5-dinitropyrazing-1-oxide (LLM-105)

Sensitivity is one of the greatest concerns in explosive materials, and its underlying mechanism remains ambiguous. In this study, 2,6-diamino-3,5- dinitropyrazine -1-oxide (LLM-105) crystals with different morphologies, such as crosswise, needle, plate, block, diamond, and spherical shapes, were prepared using a solution crystallization method, and their crystal characteristics and sensitivity were investigated. It was found that the H50 values (impact sensitivity) of LLM-105 vary within an extremely wide range of 33.8–112.2 cm and are mainly influenced by the particle morphology, crystal integrity, particle surface defects, and roughness, but are mostly independent of intracrystalline defects and particle sizes. The friction sensitivities of all samples are zero and are unaffected by the crystal characteristics. The G50 values (shock sensitivity) are within the range of 0–6.9 mm, increasing with decreasing particle sizes and the apparent crystal density. Notably, LLM-105 crystals with a spherical shape, good integrity, smooth surface, and fewer defects are insensitive to impact and shock impulse. The relationships between the crystal characteristics and the sensitivity of LLM-105 are extremely complex and show some abnormal phenomena, which can be attributed to the crystal packing style and aggregated microstructures of LLM-105.

Development of Cell Delivery System for the Subretinal Space Using Biodegradable Nanosheets

Age-related macular degeneration (AMD) is a major ophthalmic disease that causes visual impairment and blindness, particularly in elderly people. The developing choroidal vessels invade Bruch’s membrane and disrupt the monolayer of retinal pigment epithelial (RPE) cells. Subsequently, degeneration of photoreceptors occurs. Hence, subretinal transplantation of RPE cells to the site of degeneration would offer an ideal treatment providing the transplanted cells could generate a monolayer, reconstruct the RPE–photoreceptor interface, and inhibit further development of choroidal vessels. Although transplantation of autologous peripheral RPE cells has been tested by injection of cell suspensions using a syringe needle, limited visual improvement result due to the low viability of the injected cells, and their restricted distribution and integration into the subretinal tissue.Recently, we investigated the use of biodegradable polymeric nanosheets as cell scaffolds [1,2]. Because this system enabled the easy manipulation of the cell/nanosheet constructs with a syringe needle, it raises the possibility of transplanting cell sheets into a narrow space, such as the subretinal space, in a minimally-invasive manner. So far, poly(lactic-co-glycolic acid) (PLGA) was used as the material for the nanosheets. However, this biodegradable polymer is relatively inflammatory because it produces lactic and glycolic acids as degradation intermediates and these acid dissociation constants are about 3.8. In this study, we fabricated biodegradable nanosheets using polycaprolactone (PCL) and collagen as low inflammatory materials and investigated a minimally invasive and effective method for cell transplantation into the subretinal space (Fig.1(a)).Micropatterned nanosheets consisting of PCL, collagen and Nile red were prepared by a combination of spin-coating and micro-contact printing technique (Fig.1(b)). The diameter and thickness of the nanosheets used for the following experiments were 200 μm and 200 nm, respectively. The cell/nanosheet constructs were prepared by culturing rat retinal pigment epithelial (RPE-J) cells on the micropatterned nanosheets in a monolayer. A hand-made glass capillary needle was as thick as a 27G medical needle, and the tip angle was 30 degrees. Also, it was coated with 2-methayloxyethyl phosphorylcholine (MPC) to prevent cells from attaching the inner surface of the needle. The cell/nanosheet constructs and a sodium hyaluronate solution with the medium were loaded into the capillary needle. Subsequently, the cell/nanosheet was injected into the subretinal space through the sclera of rat. Several days after implantation, the rats were euthanized, and the eyeballs were enucleated.The micropatterned nanosheet was shown in Fig.1(c). The nanosheets had sufficient strength and flexibility to be handled in water. The shape or diameter of the nanosheets could be varied by adjusting the microstructure of the PDMS stamp. Also, the thickness of the nanosheets could be controlled by changing the concentration of the solution. As shown in Fig.1b, the cells formed a monolayer on the nanosheet of PCL/collagen. Finally, we attempted to deliver the RPE-J cell/nanosheet constructs to the subretinal space of a rat eye in vivo. The hand-made glass capillary needle shape allowed the needle insertion along the retina through the sclera. The fluorescence of PCL/collagen nanosheet and cells could be observed in the eyeballs under excitation light. Also, as shown in Fig.1(e), it was confirmed that the cell/nanosheet construct was successively delivered into the subretinal space.We fabricated biodegradable nanosheets using PCL and collagen as low inflammatory materials. Also, we developed a minimally invasive and effective method for cell transplantation into the subretinal space using capillary needles and confirmed that cell/nanosheet was successfully delivered. This method holds great promise for transplantation of monolayer cells and for the development of local cell delivery systems. In order to further improve this method, we plan to evaluate the inflammatory properties of the nanosheets and the efficacy of the delivered cells.

Analysis of shape, orientation and interface properties of Mo[formula omitted]C precipitates in Fe using ab-initio and finite element method calculations

We study the Mo2C precipitate, a carbide commonly used for secondary hardening in steels, and its interface to the Fe matrix using a combination of ab-initio density functional theory and finite element simulations. For Mo2C and Fe, the elastic properties as a function of temperature are determined and different interfaces of the carbide to the matrix are characterized. With finite element simulations that use the derived elastic properties and interface energies as input, the energy contributions from elasticity and creep are evaluated. Combining the results from atomic to micro scale allows to explain the specific needle shape of these precipitates that has been reported experimentally. For one selected interface, also the full elastic properties are determined with ab-initio methods and compared to the Grimsditch-Nizzoli approach, where we find good agreement. Our study shows how a combination of the ab-initio and the finite element method may be used to characterize and understand the micro-mechanical effects of precipitates.

Characterization of bio-nanocomposite films based on gelatin/polyvinyl alcohol blend reinforced with bacterial cellulose nanowhiskers for food packaging applications

Bacterial cellulose nanowhiskers (BCNW) were synthesized from Komagataeibacter xylinus (strain K2G30; UMCC 2756) using sulfuric acid hydrolysis and incorporated into a gelatin-polyvinyl alcohol (GL/PVA) blend film matrix. The effect of BCNW content (1–10 wt% of biopolymer) on the microstructural, mechanical, optical, and water barrier properties of bio-nanocomposites was studied. Transmission electron microscopy showed that BCNW had a needle shape morphology with an average length of 600 nm and an average width of 30 nm. The crystallinity index of BCNW was 94.7% using X-ray diffraction. Scanning electron microscopy (SEM) illustrated good miscibility between GL/PVA blend film matrix and BCNW up to 7.5 wt%. Fourier-transform infrared spectroscopy in the attenuated total reflection mode showed molecular interactions between functional groups of the GL/PVA blend film matrix and BCNW. The incorporation of BCNW up to 7.5% into the GL/PVA blend reduced the water vapor transmission rate and water vapor permeability by about 22% and 14%, respectively, while tensile strength, elongation at break, and elastic modulus increased by about 21.5%, 41% and 19%, respectively (p < 0.05). Films transparency was not affected by the addition of BCNW (p > 0.05) suggesting that the BCNW were dispersed uniformly at the nanoscale. All films were colorless (ΔE*<2) with low opacity value (<2) comparable to synthetic plastics. Overall, the characterization of functional properties revealed that GL/PVA blend film reinforced with BCNW could be used as an environmentally friendly packaging material to partially replace or reduce the use of current petroleum-based packaging materials.

Standardization of Poly Herbal Cosmetic Formula on Abnormal Pigmentation in Cutaneous Wound Healing – A Preliminary Study

Abnormal pigmentation in cutaneous wound healing has become a major cosmetic issue in the current society. Rising popularity of green labeled cosmetics which are environmentally sustainable with minimum side effects have greater demand in the world cosmetic market. Standardization of herbal formula is essential in order to assess the quality of drugs. Hence, the research study was designed to standardize the selected herbs based on comprehensive literary study on selected Varnaya Dravya (complexion promoting herbs) mentioned in Ayurveda authentic texts and Sri Lankan traditional manuscripts comprising of Terminalia chebula Retz, Terminalia belerica (Gaertn). Roxb, Phyllanthus emblica Linn, Rubia cordifolia Linn, Curcuma longa Trim, and Sesamum indicum Linn. Authentication of herbal ingreedients has been carried out at Bandaranayaka Memorial Ayurveda Research Institute, Nawinna, Sri Lanka. Microscopic identification, Moisture content, pH value, Total ash content and Colouring matter were tested determind through paper chromatography under WHO (2011) guidelines. Microscopic identification revealed that the poly herbal cosmetic formula in powder form contains yellow colour cells, stone cells, group of elongated stone cells, transparent cells, pitted vessels, spiral vessels, vessels filled with red, small fibers, oil globules, starch granules, needle shape crystals, hair and Trichoid. Moreover, moisture content of the formula was 6.3%, pH - 5.92 and total ash value - 4.45%. Determination of colouring matter indicated formula does not contain synthetic dyes. In addition, secondary plant metabolites like phenolic, tannins and saponins were present. Pharmacodynamics potential of the formula showed 25% kashaya (astringent) and tiktta (bitter) rasa (taste) accordingly. Further, 46% and 27% of formula showed ruksha (dryness) and laghu (lightness) guna (properties) along with 83% and 67% indicated ushna virya.&#x0D; (hot in potency) and madura (sweet) vipaka respectively. Due to presence of secondary metabolites, the poly herbal formula has anti-bacterial, anti-fungal and anti-oxidant potentials which will be favorable for skin complexion protection from bacteria and fungi. Moreover, Lekhana action gives scraping effect which is important for removing the scar.&#x0D; The study suggested that parameters found to be sufficient to evaluate the herbal cosmetic powder and could be used as reference standards and applicability of this formulae should be validated with a preclinical and clinical trials.

In Vitro Corrosion of Quaternery Magnesium Alloy Foam by Addition of Zinc

&#x0D; &#x0D; &#x0D; &#x0D; Magnesium alloys have been intensively studied as possible resorbable material with adequate mechanical properties similar to natural bones but very poor corrosion properties. In this analysis, the addition of Zn element to quaternary Mg-Ca-Zn alloy foam was evaluated with TiH2 as a foaming agent and manufactured with high-purity raw materials the powder metallurgy process. In Hank's solution, the rate of corrosion of specimens by direct observations with Scanning Electron Microscopy ( SEM), Electron Dispersion Spectrometry (EDS), static immersion studies, potentiodynamic evaluations, and X-Ray Diffraction (XRD). The specimens post-immersion characteristics and the corresponding Hank's solutions were examined at 2, 4, 6, 24, 48, and 72 hours of immersion. The findings show that the microstructure of alloy morphology, such as pores, pitting corrosion, needle shapes, and galvanic corrosion has the main corrosion products Mg(OH)2 and Ca10(PO4)6(OH)2. The addition of less than 6 percent wt Zn will minimize the corrosion rate but increase with 10 percent wt Zn. From this study, Mg-Zn-Ca alloy at 6 percent wt Zn has the lowest corrosion rate with slow pH changes in the process.&#x0D; &#x0D; &#x0D; &#x0D;

Trajectory Generation of FBG-Sensorized Needles for Insertions into Multi-Layer Tissue.

Several models incorporate needle shape prediction, however prediction in multi-layer tissue for complex needle shape remains an issue. In this work, we present a method for trajectory generation of flexible needles that allows for complex curvatures, extending upon a previous sensor-based model. This model combines curvature measurements from fiber Bragg grating (FBG) sensors and the mechanics of an inextensible elastic rod for shape-sensing. We evaluate the method's effectiveness in single- and double-layer isotropic tissue prediction. The results illustrate a valid trajectory generation method accounting for complex curvatures in flexible needles.