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The development of biodegradable bone scaffolds that align with the growth cycle of new bone has become a prominent focus in the field of bone defect repair. The sintered porous hydroxyapatite scaffolds exhibit a high degree of crystallization and demonstrate a slow degradation rate following implantation. The apatite phase with low crystallinity can be obtained following the hydration reaction of the non-sintered calcium phosphate bone cement (CPC) scaffolds. However, this leads to the formation of a weak alkaline environment during degradation, ultimately resulting in unsustainable degradation. The present study focuses on the fabrication of porous pectin/CPC composite scaffolds through two approaches during the preparation process of non-sintered porous CPC scaffolds: uniform composite and surface modification. The degradation performance of porous composite scaffolds exhibited an increase with the rise in pectin content. At a pectin content of 70 mg/mL, the scaffolds demonstrated a degradation rate of 13.79% within a span of 30 days. The mechanical properties of the porous scaffolds were enhanced with an increase in pectin concentration through surface coating. When the pectin concentration was 5 wt%, the scaffold exhibited a compressive strength of 8.72 MPa, an elastic modulus of 0.82 GPa, and experienced a degradation rate of 12.57% after a period of 30 days. The local acidic environment not only facilitates the dissolution of bone-like apatite but also enhances cell proliferation and adhesion. Pectin/apatite porous scaffolds exhibit excellent biocompatibility, offering a novel approach for the development of biodegradable bone replacement scaffolds.

In this study, biodegradable Zn-Cu-Mn alloy stents were implanted into porcine coronary artery for 18 months, and the in vivo biosafety and efficacy as well as the degradation behavior were systematically studied. Results showed a rapid endothelialization of the target vessel was achieved at 1 month post-implantation. Although the lumen diameter loss and local inflammation were observed at the early stage, the stented blood vessel could gradually recover with time. The lumen diameter was already close to normal range at 12 months, indicating good bioefficacy of the stent. No adverse effect on blood indexes or local accumulation of Zn, Cu or Mn elements were found after implantation, neither the malapposition and thrombosis were observed, which exhibited good biosafety of the stents. The stent could maintain the basic structure and mechanical integrity at 6 months, and remained only approximately 26 % of the stent volume at 18 months, suggesting a desirable degradation rate. In general, the Zn-Cu-Mn alloy stent showed great advantages and prospects in clinical application.

The primary component of natural bone minerals, hydroxyapatite (HA), has been the subject of research on materials for bone implants. Sintered HA scaffolds, on the other hand, degrade slowly after implantation and exhibit a high degree of crystallization at high temperatures, making it challenging to match the rate at which new bone grows. In this study, the benefit of self-curing calcium phosphate bone cement was employed to create porous apatite scaffolds without sintering. The lamellar pore structure was created by directional freeze-casting, and the enhanced specific surface area aided the in-situ hydration process. The crystallinity of sinterless porous apatite scaffolds diminishes when the TTCP and DCPD molar ratios drop. When the molar ratio is adjusted to 1:2.25, the crystallinity of the fabricated scaffold is reduced to 63.99 %, and 10.21 % can be degraded in 30 days. The degradation of porous scaffolds in simulated body fluids mainly depends on the rapid dissolution and transformation of solid phase powders in the early hydration reaction and the slow diffusion of the apatite in the later stage. The compressive strength of the porous scaffold is 5.3 MPa and its elastic modulus is 0.68 GPa. After 14 days of degradation, the compressive strength was 4.0 MPa and the elastic modulus was 0.64 GPa, which was still within the applicable range of cancellous bone repair. It has a promising application prospect as a substitute scaffold for absorbable cancellous bone. [ABSTRACT FROM AUTHOR]

As biodegradable materials, zinc (Zn) and zinc-based alloys have attracted wide attention owing to their great potential in biomedical applications. However, the poor strength of pure Zn and binary Zn alloys limits their wide application. In this work, a stir casting method was used to prepare the Zn-1Fe-xSr (x = 0.5, 1, 1.5, 2 wt.%) ternary alloys, and the phase composition, microstructure, tensile properties, hardness, and degradation behavior were studied. The results indicated that the SrZn13 phase was generated in the Zn matrix when the Sr element was added, and the grain size of Zn-1Fe-xSr alloy decreased with the increase in Sr content. The ultimate tensile strength (UTS) and Brinell hardness increased with the increase in Sr content. The UTS and hardness of Zn-1Fe-2Sr alloy were 141.65 MPa and 87.69 HBW, which were 55.7% and 58.4% higher than those of Zn-1Fe alloy, respectively. As the Sr content increased, the corrosion current density of Zn-1Fe-xSr alloy increased, and the charge transfer resistance decreased significantly. Zn-1Fe-2Sr alloy had a degradation rate of 0.157 mg·cm−2·d−1, which was 118.1% higher than the degradation rate of Zn-1Fe alloy. Moreover, the degradation rate of Zn-1Fe-xSr alloy decreased significantly with the increase in immersion time. [ABSTRACT FROM AUTHOR]

Blending polylactide (PLA) with poly(propylene carbonate) offers potential solution to mitigate the greenhouse effect due to PLA's lower carbon dioxide (CO2) emissions and its use of CO2 as a monomer in PPC synthesis. In this investigation, a series of PLA and PPC blends were prepared using the solvent casting method to address their respective weaknesses. The blends exhibited partial compatibility, as evidenced by a noticeable shift in the glass transition temperatures toward each other. Tensile testing revealed that the incorporation of PPC improved the elongation properties of PLA. The degradation characteristics of the blend films were evaluated based on changes in the monolayer's occupied area, the properties of the bulk film, and changes in surface morphology. Results indicated that PPC content accelerated hydrolytic degradation but slowed enzymatic degradation in the blends. Hydrolytic and enzymatic degradation significantly impacted the mechanical properties of PLA/PPC blends, prolonging the degradation process through chain scission. [ABSTRACT FROM AUTHOR]

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pesticide residues in soil, especially multiple herbicide residues, cause a series of adverse effects on soil properties and microorganisms. In this work, the degradation of three herbicides and the effect on bacterial communities under combined pollution was investigated. The experimental results showed that the half-lives of acetochlor and prometryn significantly altered under combined exposure (5.02–11.17 d) as compared with those of individual exposure (4.70–6.87 d) in soil, suggesting that there was an antagonistic effect between the degradation of acetochlor and prometryn in soil. No remarkable variation in the degradation rate of atrazine with half-lives of 6.21–6.85 d was observed in different treatments, indicating that the degradation of atrazine was stable. 16S rRNA high-throughput sequencing results showed that the antagonistic effect of acetochlor and prometryn on the degradation rate under combined pollution was related to variation of the Sphingomonas and Nocardioide. Furthermore, the potential metabolic pathways of the three herbicides in soil were proposed and a new metabolite of acetochlor was preliminarily identified. The results of this work provide a guideline for the risk evaluation of combined pollution of the three herbicides with respect to their ecological effects in soil. [ABSTRACT FROM AUTHOR]

Abstract In museums, silk cultural relics are highly sensitive to light. However, lighting is inevitable due to the exhibition needs, despite any light would pose irreversible damage to silk. Although the solution of eliminating UV radiation was widely achieved in museum lighting environment, long-time accumulation of other light sources still would induce photodegradation of silk. This work therefore established the simulated light ageing experiments to assess the degradation behaviors of silk samples with different ageing degrees. The variation of color values and structure transformation of each sample group were determined by the means of scanning electron microscopy (SEM), colorimeter, Fourier Transform infrared spectroscopy (FTIR) and 13C CPMAS NMR. The results indicated that silk samples with different initial ageing degrees presented different discoloration tendency and structural variation in experimental lighting environment, suggesting the higher disordered structure makes the silk more vulnerable to light damage. It is of great significance to understand the long-time impacts of illumination on degraded silk and further provide methodology for predicting the duration of exhibited silk cultural relics.

Herein, a novel strategy, namely Vat photopolymerization-assisted template replacement method was developed to achieve elaborate triply periodic minimal surface structure and different pore sizes in biodegradable Zn-based porous scaffolds. The pore structure, microstructure, phase constitution, degradation properties, mechanical performance, in vitro cytocompatibility and antibacterial activity were systematically investigated. As a result, triply periodic minimal surface structures with different pore sizes were successfully obtained in Zn–1Mg porous scaffolds. The actual porosity closely matched the designed porosity, demonstrating the efficacy of the new strategy in achieving precise pore structures with a difference below 2%. Zn–1Mg scaffolds, designed with a pore size of 780 mm, exhibited a uniaxial compressive strength of 59.95 MPa and an elastic modulus of 3.07 GPa. Furthermore, the mechanical integrity was well-maintained even after 28 days of immersion, attributed to the substantial deposition of calcium-phosphate-rich corrosion products within the porous structure. More importantly, a suitable weight loss rate of about 15% were confirmed after 28 days immersion, indicating a period for total degradation of approximately 13 months based on a linear degradation assumption. Further, the experimental scaffolds demonstrated good cytocompatibility with MC3T3-E1 preblast cells and exhibited significant antibacterial activity against both Staphylococcus aureus and Escherichia coli.

Additively manufactured (AM) biodegradable zinc (Zn) alloys have recently emerged as promising porous bone-substituting materials, due to their moderate degradation rates, good biocompatibility, geometrically ordered microarchitectures, and bone-mimicking mechanical properties. While AM Zn alloy porous scaffolds mimicking the mechanical properties of trabecular bone have been previously reported, mimicking the mechanical properties of cortical bone remains a formidable challenge. To overcome this challenge, we developed the AM Zn-3Mg alloy. We used laser powder bed fusion to process Zn-3Mg and compared it with pure Zn. The AM Zn-3Mg alloy exhibited significantly refined grains and a unique microstructure with interlaced α-Zn/Mg 2 Zn 11 phases. The compressive properties of the solid Zn-3Mg specimens greatly exceeded their tensile properties, with a compressive yield strength of up to 601 MPa and an ultimate strain of >60 %. We then designed and fabricated functionally graded porous structures with a solid core and achieved cortical bone-mimicking mechanical properties, including a compressive yield strength of >120 MPa and an elastic modulus of ≈20 GPa. The biodegradation rates of the Zn-3Mg specimens were lower than those of pure Zn and could be adjusted by tuning the AM process parameters. The Zn-3Mg specimens also exhibited improved biocompatibility as compared to pure Zn, including higher metabolic activity and enhanced osteogenic behavior of MC3T3 cells cultured with the extracts from the Zn-3Mg alloy specimens. Altogether, these results marked major progress in developing AM porous biodegradable metallic bone substitutes, which paved the way toward clinical adoption of Zn-based scaffolds for the treatment of load-bearing bony defects. Our study presents a significant advancement in the realm of biodegradable metallic bone substitutes through the development of an additively manufactured Zn-3Mg alloy. This novel alloy showcases refined grains and a distinctive microstructure, enabling the fabrication of functionally graded porous structures with mechanical properties resembling cortical bone. The achieved compressive yield strength and elastic modulus signify a critical leap toward mimicking the mechanical behavior of load-bearing bone. Moreover, our findings reveal tunable biodegradation rates and enhanced biocompatibility compared to pure Zn, emphasizing the potential clinical utility of Zn-based scaffolds for treating load-bearing bony defects. This breakthrough opens doors for the wider adoption of zinc-based materials in regenerative orthopedics. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of China Synthetic Fiber Industry is the property of Sinopec Baling Petrochemical Company and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Renewable lignocellulosic biomass is a favorable energy resource since its co-pyrolysis with hydrogen-rich plastics can produce high-yield and high-quality biofuel. In contrast to earlier co-pyrolysis research that concentrated on increasing product yield, this study comprehends the synergistic effects of two distinct feedstocks that were not considered earlier. This work focuses on co-pyrolyzing wheat straw (WS) with non-reusable polyethylene terephthalate (PET) for the production of pyrolysis oil. WS and PET were blended in different ratios (100/0, 80/20, 60/40, 40/60, 20/80, and 0/100), and pyrolysis experiments were conducted in a fixed-bed reactor under different temperatures to assess their synergistic effect on oil yield. Synergy rates of up to 7.78 % were achieved on yield for the blends of plastic and biomass at a temperature of 500 °C. In comparison to individual biomass or plastics, co-pyrolyzing PET-biomass blends demonstrated good process interaction and promoted the yields of value-added products. The heating value of the pyrolysis oils was in the range of 16.45–28.64 MJ/kg, which depends on the amount of plastic present in the feedstock. The physical analysis of the oils shows that they can be used for heat production by direct combustion in boilers or furnaces. The correlation between WS and PET was validated with the aid of Fourier transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS) analysis. The GC-MS result demonstrated the presence of different compounds such as O-H compounds, esters, carbonyl group elements, acids, hydrocarbons, aromatics, and nitrogenated compounds in the pyrolysis oil, which differed based on the proportions of PET in the feedstock. The increased hydrocarbon and reduced oxygen percentages in the pyrolysis oil were implicitly caused by enhanced hydrocarbon pool mechanisms, in which the breakdown of PET may be supplied as a hydrogen donor. Overall, waste lignocellulosic biomass and plastics can be used to produce biofuels, which helps reduce the amount of solid waste that ends up in landfills. This study also revealed that future research should be focused on the reaction mechanisms of WS and PET co-pyrolysis in order to examine the synergistic interactions.

The degradation of Mg alloys relates to the service performance of Mg alloy biodegradable implants. In order to investigate the degradation behavior of Mg alloys as vascular stent materials in the near service environment, the hot-extruded fine-grained Mg-Zn-Y-Nd alloy microtubes, which are employed to manufacture vascular stents, were tested under radial compressive stress in the dynamic Hanks’ Balanced Salt Solution (HBSS). The results revealed that the high flow rate accelerates the degradation of Mg alloy microtubes and its degradation is sensitive to radial compressive stress. These results contribute to understanding the service performance of Mg alloys as vascular stent materials.

Two-dimensional black phosphorus (2D BP) has attracted significant research interest in the field of biomedical applications due to its unique characteristics, including high biocompatibility, impressive drug-loading efficiency, phototherapeutic ability, and minimal side effects. However, its puckered honeycomb lattice structure with lone-pair electrons of BP leads to higher sensitivity and chemical reactivity towards H2O and O2 molecules, resulting in the degradation of the structure with physical and chemical changes. In our study, we synthesize polyethylene glycol (PEG) and glutathione-stabilized doxorubicin drug-assembled Au nanoparticle (Au-GSH-DOX)-functionalized BP nanosheets (BP-PEG@Au-GSH-DOX) with improved degradation stability, biocompatibility, and tumor-targeting ability. Transmission electron microscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy indicate the nanoscale degradation behavior of synthesized nanoconjugates in three different environmental exposure conditions, and the results demonstrate the remarkable nanoscale stability of BP-PEG@Au-GSH-DOX against the degradation of BP, which provides significant interest in employing 2D BP-based nanotherapeutic agents for tumor-targeted cancer phototherapy. [ABSTRACT FROM AUTHOR]

Mg–Ag alloy has potential as a material for bone tissue repair, but the faster degradation rate in vivo limits its use in medical applications. In this study, pure Mg and Mg99.5Ag0.5 alloy with a porous structure are prepared using the metal/gas eutectic unidirectional solidification method (Gasar process). The influence of introducing Ag on the degradation behavior of porous Mg99.5Ag0.5 and pure Mg is investigated. The addition of Ag increases the compressive strength and elastic modulus of the material. The corrosion resistance of as‐cast Mg99.5Ag0.5 alloy decreases due to localized aggregation of Ag in the alloys. Therefore, the T4 (solution treatment) is chosen for the Mg99.5Ag0.5 alloy. After T4 treatment, due to the uniform distribution of Ag atoms in the alloy, the corrosion behavior on the alloy surface is more uniform, and a denser Mg(OH)2 passivation layer is formed on the surface, which reduces the degradation rate of Mg99.5Ag0.5. Importantly, insoluble Ca–P compounds in the form of hydroxyapatite (HA) phases gradually grown on passivated layers of porous T4 Mg99.5Ag0.5 contribute to bone growth. This indicates the feasibility of using the T4 Gasar porous Mg99.5Ag0.5 alloy as a potential tissue engineering scaffold. [ABSTRACT FROM AUTHOR]

This study evaluated the biological response of cold-sprayed coatings composed of bioactive glass 45S5 and polyetheretherketone (PEEK). The functional coatings were produced by cold gas spray (CGS) technology, a technique that allows the deposition of powders at significantly low temperatures, avoiding heat damage to polymeric surfaces. By CGS, blends with different ratios of bioactive glass and PEEK powders have been deposited onto PEEK substrates to improve the response of the bio-inert polymer. The bioactivity of the coatings when immersed in a simulated body fluid solution was evaluated by observation with scanning electron microscopy (SEM) and x-ray diffraction (XRD). Results verify that bioactive glass particles in the composite coatings enhance their bioactivity. A degradation test was performed with Tris–HCl solution. From the results obtained by inductively coupled plasma optical emission spectroscopy (ICP-OES) and the weight loss of the samples, it was noticed that the degradation was directly related to the amount of glass in the coatings. Finally, the ability of bone-forming cells to adhere and proliferate on the coatings was evaluated. These experiments showed that the presence of glass particles does not cause a significant increase in cell proliferation. Combining a bioactive material with PEEK leads to forming a final component that provides suitable bioactivity to the final implant. [ABSTRACT FROM AUTHOR]

The objective of this work is to investigate the hydrolytic degradation of the Monocryl (PGA/PCL) surgical suture in different pH buffer solutions, and its correlation with the structural alterations the material undergoes. To this end, an in vitro degradation study was conducted under acidic (pH = 2), physiological (pH = 7.4), and alkaline (pH = 8.5) conditions at 37 °C, over 25 days. Changes in the swelling rate, structural and mechanical properties of the Monocryl sample with the degradation time were characterized, from which the related degradation mechanism of the material was concluded. Results showed that the structural values of the Monocryl sample were more sensitive in the alkaline medium than the acidic and neutral ones. It exhibited a reduction in birefringence values by 11.5% from the original one in the buffer solution of pH = 8.5, only 4% at pH = 2, and 2.6% at pH = 7.4, after 20 days of degradation durations. Over the same time period, mechanical loss in neutral, acidic, and alkaline media was decreased to 19, 14.9, and 8.3%, respectively. The obtained results revealed that the Monocryl suture exhibits enhanced degradation properties in neutral conditions rather than both acidic and alkaline ones, with a more homogeneous degradation behavior during the degradation process. [ABSTRACT FROM AUTHOR]

• Radial compressive stress was introduced in the degradation test of mg microtubes. • Dynamic medium and radial compressive stress accelerate mg microtubes degradation. • The degradation mechanism of mg microtube under different environments was proposed. The degradation of Mg alloys relates to the service performance of Mg alloy biodegradable implants. In order to investigate the degradation behavior of Mg alloys as vascular stent materials in the near service environment, the hot-extruded fine-grained Mg-Zn-Y-Nd alloy microtubes, which are employed to manufacture vascular stents, were tested under radial compressive stress in the dynamic Hanks' Balanced Salt Solution (HBSS). The results revealed that the high flow rate accelerates the degradation of Mg alloy microtubes and its degradation is sensitive to radial compressive stress. These results contribute to understanding the service performance of Mg alloys as vascular stent materials. [ABSTRACT FROM AUTHOR]

This study proposes a fiber beam-column model that takes into account the anisotropy of wood and the embedment behavior of the rocking column to assess the impact of wood damage on the lateral performance of traditional Chinese timber structures. Subsequently, numerical analyses corresponding to a full-scale quasi-static test of a traditional Chinese timber framework are conducted to verify the accuracy of this fiber beam-column model. By considering factors such as residual deformation and wood decay in the column base, the degradation behavior of traditional Chinese timber structures can be evaluated. This study provides a foundation for discussing and further researching the damage assessment of traditional Chinese timber structures.

As biodegradable materials, zinc (Zn) and zinc-based alloys have attracted wide attention owing to their great potential in biomedical applications. However, the poor strength of pure Zn and binary Zn alloys limits their wide application. In this work, a stir casting method was used to prepare the Zn-1Fe-xSr (x = 0.5, 1, 1.5, 2 wt.%) ternary alloys, and the phase composition, microstructure, tensile properties, hardness, and degradation behavior were studied. The results indicated that the SrZn13 phase was generated in the Zn matrix when the Sr element was added, and the grain size of Zn-1Fe-xSr alloy decreased with the increase in Sr content. The ultimate tensile strength (UTS) and Brinell hardness increased with the increase in Sr content. The UTS and hardness of Zn-1Fe-2Sr alloy were 141.65 MPa and 87.69 HBW, which were 55.7% and 58.4% higher than those of Zn-1Fe alloy, respectively. As the Sr content increased, the corrosion current density of Zn-1Fe-xSr alloy increased, and the charge transfer resistance decreased significantly. Zn-1Fe-2Sr alloy had a degradation rate of 0.157 mg·cm−2·d−1, which was 118.1% higher than the degradation rate of Zn-1Fe alloy. Moreover, the degradation rate of Zn-1Fe-xSr alloy decreased significantly with the increase in immersion time.

Pesticide residues in soil, especially multiple herbicide residues, cause a series of adverse effects on soil properties and microorganisms. In this work, the degradation of three herbicides and the effect on bacterial communities under combined pollution was investigated. The experimental results showed that the half-lives of acetochlor and prometryn significantly altered under combined exposure (5.02–11.17 d) as compared with those of individual exposure (4.70–6.87 d) in soil, suggesting that there was an antagonistic effect between the degradation of acetochlor and prometryn in soil. No remarkable variation in the degradation rate of atrazine with half-lives of 6.21–6.85 d was observed in different treatments, indicating that the degradation of atrazine was stable. 16S rRNA high-throughput sequencing results showed that the antagonistic effect of acetochlor and prometryn on the degradation rate under combined pollution was related to variation of the Sphingomonas and Nocardioide. Furthermore, the potential metabolic pathways of the three herbicides in soil were proposed and a new metabolite of acetochlor was preliminarily identified. The results of this work provide a guideline for the risk evaluation of combined pollution of the three herbicides with respect to their ecological effects in soil.

Biodegradable zinc (Zn) alloys are promising implant materials to restore bone defects in orthopedics. Adding silver (Ag) to Zn not only enhances its mechanical properties but also improves its antibacterial properties. However, the regular pattern of Ag composition on the properties of Zn-xAg alloys remains unclear. In this paper, Zn-Ag alloys with different Ag contents ranging from 0.5 to 6.0% were prepared by casting process and were systematically investigated both in vitro and in vivo. Mechanical tests suggest that the increase of Ag content enhanced the yield strength (YS), ultimate tensile strength (UTS), Vickers hardness, and elongation. Compared with pure Zn, the maximum YS, UTS, Vickers hardness, and elongation were achieved at Zn-6Ag, which were increased by 267%, 295%, 115%, and 172%, respectively. The degradation rate increased and the antibacterial properties were enhanced accordingly. All 25% and most 50% extracts of Zn-Ag alloys significantly promoted the proliferation of MC3T3-E1 cells, except for 50% Zn-6Ag extracts showing cytotoxicity. In the rat femoral condyle model, Zn-2Ag and Zn-4Ag alloys exhibited enhanced osteogenic performance at the early stage of implantation compared with pure Zn. Zn-Ag alloys (especially Zn-2Ag and Zn-4Ag) are identified as promising bone repair materials.

Current materials comprising suture anchors used to reconstruct ligament-bone junctions still have limitation in biocompatibility, degradability or mechanical properties. Magnesium alloys are potential bone implant materials, and Mg2+ has been shown to promote ligament-bone healing. Here, we used Mg-2 wt.% Zn-0.5 wt.% Y-1 wt.% Nd-0.5 wt.% Zr (ZE21C) alloy and Ti6Al4V (TC4) alloy to prepare suture anchors to reconstruct the patellar ligament-tibia in SD rats. We studied the degradation behavior of the ZE21C suture anchor via in vitro and in vivo experiments and assessed its reparative effect on the ligament-bone junction. In vitro, the ZE21C suture anchor degraded gradually, and calcium and phosphorus products accumulated on its surface during degradation. In vivo, the ZE21C suture anchor could maintain its mechanical integrity within 12 weeks of implantation in rats. The tail of the ZE21C suture anchor in high stress concentration degraded rapidly during the early implantation stage (0–4weeks), while bone healing accelerated the degradation of the anchor head in the late implantation stage (4–12weeks). Radiological, histological, and biomechanical assays indicated that the ZE21C suture anchor promoted bone healing above the suture anchor and fibrocartilaginous interface regeneration in the ligament-bone junction, leading to better biomechanical strength than the TC4 group. Hence, this study provides a basis for further research on the clinical application of degradable magnesium alloy suture anchors.

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim of the study The objective of this study was to compare biodegradable biomaterials from MgCaGd and MgCaZr systems in terms of their physicochemical properties, degradation behavior and biocompatibility, with the aim of evaluating their potential application in maxillary/mandible bone reconstruction. Material and methods Biomaterials composed of magnesium (Mg), calcium (Ca), gadolinium (Gd) and zirconium (Zr) were obtained by casting in an inert Argon atmosphere, using high purity elements in the casting phase. The samples were characterized for their elemental composition using energy dispersive X-ray spectroscopy (EDS) and analyzed for their microstructural properties using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The degradation behavior of the materials was evaluated by immersing the samples in simulated body fluid (SBF) and monitoring changes in pH and ion release over time. In addition, cell viability and morphology were assessed by seeding human osteoblast-like cells on the biomaterial surfaces. The tests and determinations were carried out in the laboratories of the Technical University “Gh. Asachi” Iasi. Results EDS analysis confirmed the presence of Mg, Ca, Gd and Zr in the compositions of the respective biomaterials. SEM and XRD analysis revealed a homogeneous microstructure with well-defined crystalline phases in both MgCaGd and MgCaZr samples. The degradation study showed that the MgCaGd and MgCaZr biomaterials exhibited a controlled degradation behavior with gradual increase in pH and ion release over time. Cell viability tests demonstrated good biocompatibility as evidenced by high cell viability and normal cell morphology observed on both surfaces of the biomaterial. Conclusions Biodegradable biomaterials from MgCaGd and MgCaZr systems demonstrated comparable physicochemical properties, degradation behavior and biocompatibility. These findings highlight their potential as promising candidates for bone reconstruction applications in the mandible. Further in vivo studies are needed to validate their performance and evaluate their long-term effects on bone regeneration.

Existing research suggested 300∼600 μm as the optimal pore size range for metallic bone implants. The human bones, however, have numerous pores smaller than 300 μm for bone ingrowth, cell growth and migration, fluid flow, and so forth. The bone implant with such small-sized pores has been rarely manufactured and its property is unclear. In the paper, biodegradable Fe scaffolds of different pore sizes (50 μm, 100 μm, 150 μm, 200 μm, and 300 μm) were fabricated by direct ink writing (DIW) with subsequent sintering. The interconnected pores of all scaffolds are highly precise and have no residual powders. The in-vitro degradation and compression tests were conducted on the scaffolds to evaluate the effect of pore size on degradation and mechanical behaviors, respectively. The results indicate that a decrease in pore size leads to an increase in degradation rate, from 0.0423 ± 0.0014 to 0.0433 ± 0.0035 mm/year, with the exception of the 50 μm scaffolds which exhibit the lowest value of 0.0052 ± 0.0018 mm/year due to clogging by degradation products; meanwhile, both elastic modulus and yield strength rise from 344.8 ± 18.6 MPa to 625.0 ± 52.5 MPa and from 9.5 ± 0.9 MPa to 15.1 ± 0.8 MPa, respectively. The pore size of 100 μm shows the most significant potential for use in Fe bone implants regarding its good degradation and mechanical behaviors. Our work provides new insight into the preferable pore size of metallic bone implants produced by additive manufacturing.

Abstract Doxorubicin (DRB) is an anthracycline oncogenic drug extracted from cultures of Streptomyces peucetius var. caesius. It is frequently recommended as an anti-neoplastic agent for the treatment of diverse malignancies. It exerts its antineoplastic effect either via inhibiting the enzyme topoisomerase II and/or via intercalation to DNA or reactive oxygen species generation. In the present article, the direct, simple, one-pot, somewhat eco-safe, and non-extractive spectrophotometric system was executed to track doxorubicin, a chemotherapeutic remedy, in the presence of paclitaxel, a naturally occurring Taxan antineoplastic radical, through the greenness rated method. DRB’s optical density was studied in various mediums and solvents to develop the current approach. An acidic ethanolic solution was found to increase the optical density of the sample significantly. At 480 nm., the most remarkable optical density was obtained. Various experimental factors, including intrinsic media, solvent, pH, and stability time, were investigated and controlled. The current approach achieved linearity within the 0.6–40.0 µg mL-1 range, accompanied by a limit of both detection and quantification (LOD and LOQ) of 0.18 and 0.55 µg mL-1, correspondingly. The approach was validated under the ICH guidelines (Quality Guidelines). The system’s greenness and enhancement degree were estimated.

Bio-based monomers appear to be more attractive and increasingly important due to their potential to reduce the environmental impact of traditional petrochemical-based polymer production. This study deals with the synthesis, characterization, and degradation of triblock copolymers containing polylactide (PLA) and bio-based polyether polyol. Although the glass transition and melting temperature of copolymers decrease with polyether polyol content, copolymerization of lactide with the polyether polyol shows slower enzymatic degradation behavior than PLA itself by using both Langmuir monolayers and thin films. Overall, controlling the degradation of biodegradable polymers is useful for the commodity industries because it provides a sustainable and customizable solution. [ABSTRACT FROM AUTHOR]

Polymer foam, a special form of polymer, usually demonstrates some unexpected properties that rarely prevail in the bulky polymer. Studying the thermal degradation behavior of a specific polymer foam is important for its rational design, quick identification, objective evaluation, and industrial application. The present study aimed to discover the thermal degradation mechanism of high-temperature-resistant phthalonitrile (PN) foam under an inert gas atmosphere. The macroscopic thermal decomposition of PN foam was carried out at the cost of size/weight loss, resulting in an increasing number of open cells with pyrolyzation debris. Using the TGA/DTG/FTIR/MS technique, it was found that PN foam involves a three-stage thermal degradation mechanism: (I) releasing gases such as H2O, CO2, and NH3 generated from azo-containing intermediate decomposition and these trapped in the closed cells during the foaming process; (II) backbone decomposition from C-N, C-O, and C-C cleavage in the PN aliphatic chain with the generation of H2O, CO2, NH3, CO, CH4, RNH2, HCN, and aromatic gases; and (III) carbonization into a final N-hybrid graphite. The thermal degradation of PN foam was different from that of bulky PN resin. During the entire pyrolysis of PN foam, there was a gas superposition phenomenon since the release of the decomposition volatile was retarded by the closed cells in the PN foam. This research will contribute to the general understanding of the thermal degradation behavior of PN foam at the macroscopic and molecular levels and provide a reference for the identification, determination, and design of PN material. [ABSTRACT FROM AUTHOR]

This paper focuses on effect of rhodium addition on degradation behavior of Ir-10 mass％Rh alloy for a spark plug during oxidation at elevated temperatures. Oxidation tests were conducted at the temperature range from 1173 K to 1473 K in Ar-21％O2 gas mixture to clarify the effect of rhodium addition on degradation behavior of the alloy. As a result, there are three effects of rhodium addition to prevent the alloy from the degradation: (1) dissolution of rhodium into iridium oxide scale at below 1273 K, which decreases activity of iridium oxide in the oxide scale, (2) dissolution of rhodium into the alloy at above 1273 K, which decreases activity of iridium in the alloy and (3) formation of rhodium oxide, which decreases surface area of the alloy. All effects contribute to decrease vapor pressure of volatile iridium oxide, resulting in suppression of the degradation. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) has been widely used in many fields because of its good biodegradability, biocompatibility, and renewability. This work studied the degradation behavior and mechanical properties of cellulose nanofiber (CNF)/PLA composites. In vitro degradation experiments of 3D-printed samples were conducted at elevated temperatures, and the degradation characteristics were evaluated by mechanical tests, gel permeation chromatography (GPC), differential scanning calorimetric (DSC), and scanning electron microscope (SEM). The results indicated that the addition of CNF (0.5 wt%) accelerated the degradation rate of PLA. The decreases in number average molecular weight ( M n ) and weight average molecular weight  (M w)  of composites were 7.96% and 4.91% higher than that of neat PLA, respectively. Furthermore, the tensile modulus of composites was 18.4% higher than that of neat PLA, while the strength was 7.4% lower due to poor interfacial bonding between CNF and PLA. A mapping relationship between accelerated and normal degradation showed that the degradation experienced during 60 days at 37 °C was equivalent to that undergone during 14 days at 50 °C; this was achieved by examining the alteration in  M n . Moreover, the degradation process caused a notable deformation in the samples due to residual stress generated during the 3D printing process. This study provided valuable insights for investigating the in vitro degradation behavior of 3D-printed products. [ABSTRACT FROM AUTHOR]

Articular cartilage with limited ability of regeneration remains a grand challenge in the field of tissue engineering. Poly(vinyl alcohol) (PVA) hydrogel with low friction coefficient have been regarded as prior candidate for cartilage substitute, whereas lack of structure performance and bioactivity limited their application. Phosphate glass fiber (PGF) with outstanding mechanical performance and nature of biodegradability presents potential capability to improve mechanical stability of hydrogel and chondrocyte metabolism as well as cell recruitment. Herein, we describe a novel PGF-PVA composites hydrogel incorporated with continuous PGF. The presence of stiff PGF not only improves the mechanical properties of hydrogel with maximum tensile strength of 12.44 MPa and Young's modulus of 68.35 MPa, but also endows the hydrogel molecular structure with the increase of crystallinity and thermal stability via formation of crosslinking points. More importantly, the PVA hydrogel matrix exhibits efficient ions exchange behavior to control ions concentration during PGF degradation, resulting in more suitable metabolic environment for chondrocyte proliferation and induction with enhanced recruitment. Therefore, it is believed that this work provides a kind of fiber reinforced hydrogel material promising excellent properties for cartilage repair.

Biodegradable magnesium (Mg) and its alloy show huge potential as temporary bone substitute due to the favorable biocompatibility and mechanical compatibility. However, one issue deserves attention is the too fast degradation. In this work, mesoporous bioglass (MBG) with high pore volume (0.59 cc/g) and huge specific surface area (110.78 m2/g) was synthesized using improved sol-gel method, and introduced into Mg-based composite via laser additive manufacturing. Immersion tests showed that the incorporated MBG served as powerful adsorption sites, which promoted the in-situ deposition of apatite by successively adsorbing Ca2+ and HPO42−. Such dense apatite film acted as an efficient protection layer and enhanced the corrosion resistance of Mg matrix, which was proved by the electrochemical impedance spectroscopy measurements. Thereby, Mg based composite showed a significantly decreased degradation rate of 0.31 mm/year. Furthermore, MBG also improved the mechanical properties as well as cell behavior. This work highlighted the advantages of MBG in the fabrication of Mg-based implant with enhanced overall performance for orthopedic application.

The extraction of fibroin (degumming) from the silk fibers impacts the properties of silk fibroin. However, the effect of the degumming method on structures and properties of regenerated Antheraea pernyi silk fibroin (ASF) biomaterials has not been investigated in detail. In this study, Na2CO3 and NaHCO3 are selected to remove sericin of Antheraea pernyi silks. The results show that the silk fibroin prepared by NaHCO3 degumming possessed a higher molecular weight, demonstrated by SDS-PAGE and viscosity testing. Na2CO3 degumming produced more low molecular weight silk fibroin protein below 40 kDa, whereas NaHCO3 processing produced more silk fibroin protein above 70 kDa. The increased molecular weight significantly improved the mechanical properties of ASF film. The enzyme degradation results indicated that the degradation rate of ASF film prepared by Na2CO3 degumming was faster in the early stage due to the presence of low molecular weight silk fibroin. After 21 days, the two silk fibroin films showed approximate degradation ratios. These results showed that the degumming conditions have a significant effect on the structure and properties of ASF biomaterials, and provide options for regulating the mechanical properties and degradation rate of ASF biomaterials.

Evaluating the physical degradation behavior and estimating the lifetime of engineering systems and structures is crucial to ensure their safe and reliable operation. However, measuring lifetime through actual operating conditions can be a difficult and slow process. While valuable and quick in measuring lifetimes, accelerated life testing is often oversimplified and does not provide accurate simulations of the exact operating environment. This paper proposes a data-driven framework for time-efficient modeling of field degradation using sensor measurements from short-term actual operating conditions degradation tests. The framework consists of two neural networks: a physics discovery neural network and a predictive neural network. The former models the underlying physics of degradation, while the latter makes probabilistic predictions for degradation intensity. The physics discovery neural network guides the predictive neural network for better life estimations. The proposed framework addresses two main challenges associated with applying neural networks for lifetime estimation: incorporating the underlying physics of degradation and requirements for extensive training data. This paper demonstrates the effectiveness of the proposed approach through a case study of atmospheric corrosion of steel test samples in a marine environment. The results show the proposed framework's effectiveness, where the mean absolute error of the predictions is lower by up to 76% compared to a standard neural network. By employing the proposed data-driven framework for lifetime prediction, systems safety and reliability can be evaluated efficiently, and maintenance activities can be optimized. [ABSTRACT FROM AUTHOR]

Pharmaceuticals and personal care products (PPCPs) are a class of chemicals used by humans for daily life. PPCPs are closely related to people’s production and life, and are even used every day worldwide. PPCP-like compounds were first detected in treated wastewater in Kansas City, USA in 1976 (concentrations of 0.8-2μg/L[6]), and subsequently detected in various countries. The mass production and use of PPCPs have led to increasing concentrations in the environment. PPCPs can induce microorganisms to produce resistance genes because of their persistence and bioaccumulation, thus changing the structure and community of microorganisms in the ecosystem. At the same time, they are accumulated at the top of the food chain or food web[17-21], destroying the balance of the ecosystem. In addition, PPCPs also have chronic toxicity, teratogenicity and carcinogenicity. For example, sulfonamides will damage tissues and organs and cause drug resistance of pathogenic bacteria[9]. Synthetic musk interferes with the secretion of hormones and can also lead to asthma, allergies, migraines and other diseases[20]. Long-term use will lead to liver and kidney damage and induce cancer[21], causing irreversible damage to human health.　　PPCPs are mainly accumulated in the environment through hospitals, landfills, farms, factory wastewater and domestic sewage, and enter the water environment through various pathways. After the production of PPCPs, some are used by humans, some are directly generated in the production of waste, and some are used by animals in livestock farms. The solid or liquid waste generated in the above three ways will enter the sewage treatment plant or landfill. Then through sewage, landfill leachate directly into the surface water, through further infiltration into the sediment, pore water, groundwater, ocean and other environments, in addition to the surface water through evaporation and precipitation can also return to the water environment. The above environmental behaviors will cause harm to the ecological environment, ecosystem, and humans.　　PPCPs exist in surface water, groundwater, sediment, and other environmental media, but the pollution degree varies in different countries. In recent years, a large concentration of PPCPs has been detected in various water environmental media, and sulfonamides, antibiotics, ibuprofen, carbamazepine and DEET are widely distributed in the environment, among which sulfamethoxazole has the highest detection frequency and the highest concentration can reach 1080ng/L[8]. China is the world's largest consumer of drugs, with more than 20000t PPCPs used annually, which have been widely detected in surface water, groundwater, soil and sediments, among which antibiotics transmitted through water bodies are used more[7] than others. In addition, PPCPs are also detected in water environmental media in the United States[50], Europe[57], and Africa[9], and the study found that the concentration of PPCPs is positively correlated with the degree of economic development. In China, the highest concentration of sulfamethoxazole is detected in the sediments of the Qingpu District of Shanghai, with a concentration of 688.59ng/L[44], while the highest concentration of sulfamethoxazole in other countries is detected in groundwater of the United States, with a concentration of 1110ng/L[50]. The concentration of PPCPs in pore water and seawater is relatively low, and caffeine is the most widely detected PPCP in seawater. Some compounds have been detected in rainwater because of their volatility. Atrazine has been reported in Mississippi and at the mouth of the Yangtze River[60-61]. The presence of ofloxacin and ciprofloxacin has also been detected in Minnesota, USA[38]. PPCPs in groundwater are mainly produced through the infiltration of domestic sewage, hospital and aquaculture wastewater, and compounds with greater polarity are more likely to penetrate into groundwater[59]. Antibiotics such as lincomycin and erythromycin have been detected in groundwater in North America, Jianghan Plain of China[53,50] and Harbin[52]. Carbamazepine is one of the most commonly detected drugs in sediments, and it has been reported in the Haihe River and Baiyang Lake[55], with the highest concentration of 14.7ng/g, and also in the sediments of the Taihu Lake Basin[54], the concentrations of ciprofloxacin and ofloxacin are relatively high, 15.33ng/g and 18.27ng/g respectively. The ocean is considered by many to be an important sink of pollutants. Studies have found that more than 20 kinds of antibiotics with concentrations as high as μg/L have been detected in seawater[62]. Among them, caffeine has been widely detected in the Aegean and Baltic Sea. Besides caffeine, sulfamethoxazole and clarithromycin also have a high detection frequency[57]. PPCPs were also detected in pore water and rainwater. The pore water samples of Baiyangdian Lake[55] mainly contain erythromycin and caffeine, but their concentrations are much lower than those of surface water in the same area. In Taihu Lake[56], the concentrations of oxytetracycline and ofloxacin are found, but the concentrations of surface water are lower than those of pore water. Therefore, the different physical and chemical conditions of environmental substrates in different study areas are considered to be the cause. There are relatively few reports of PPCPs in rainwater, and the content of PPCPS is less than 10ng/L.　　PPCPs will degrade after entering water, and different degradation processes have their own degradation mechanisms. The degradation behavior of PPCPs in water mainly includes hydrolysis, photodegradation and biodegradation. Hydrolysis is an important way to eliminate or reduce the concentration of PPCPs in a water environment. Its essence is nucleophilic substitution reaction, that is, the nucleophilic group (hydroxide ion or water molecule) attacks the electrophilic group in the compound (RX), and replaces the associated strong electron-withdrawing group (X) with a negative electric tendency. For example, the hydrolysis of penicillin G and amoxicillin is the intramolecular nucleophilic attack of the side chain on the β-lactam carbonyl group, and the C-N bond is broken causing degradation. Degradation can be divided into direct photolysis and indirect photolysis processes. PPCPs with light-absorbing groups can be directly degraded by absorbing light energy. PPCPs without light-absorbing groups need to absorb photons through other substances to obtain energy, so that indirect photodegradation occurs. For example, atenolol is a degradation process that directly absorbs light energy, while acyclovir is an indirect photodegradation process by adding a catalyst. Biodegradation means that microorganisms change the chemical structure of PPCPs through a series of biochemical reactions under aerobic or anoxic conditions, and finally achieve the purpose of removal. At present, studies on the biodegradation of PPCPs mainly focus on three aspects: sewage treatment system, natural surface water and laboratory simulation system[79]. For sewage treatment plants, PPCPs are mainly removed through biodegradation of secondary treatment[80].　　The degradation of PPCPs is affected by various factors, among which pH and temperature are the main influencing factors. The study on hydrolysis of PPCPs mainly considers the influence of pH on PPCPs. Different pH and target compounds will have different reactions, which have certain effects on the hydrolysis rate and hydrolysis products. In addition, temperature will also affect hydrolysis. In general, the higher the temperature, the faster the hydrolysis of a compound[61], because the hydrolysis process of a compound is a thermal reaction, and the activation energy mainly comes from the collision between molecules. The mechanism of photodegradation of PPCPs in water mainly lies in the molecular absorption of light energy into an excited state, which triggers various reactions[71]. There are many factors affecting the photodegradation of PPCPs in a water environment, mainly including pH of water and co-existing ions. It is generally believed that the higher pH in a water environment, the faster the photodegradation rate. Because many PPCP molecules contain acid-base dissociative groups, they are easily ionized in aqueous solution to produce a variety of dissociative forms, and the reason for affecting the ionization of PPCPs is the change of solution pH[74]. The presence of co-existing ions can either promote or inhibit the photodegradation of pollutants. The pH and temperature of the environment will affect the absorption, growth and metabolism of nutrients by microorganisms, thus changing the growth and living state of microorganisms, and then affecting biodegradation[82]. In addition, different compounds have different sensitivity to pH and temperature in the process of biodegradation. Also, the types of degraded strains have a certain impact on degradation. In general, photodegradation and biodegradation are more common than hydrolysis. In surface water, many PPCPs have avoided the strict biodegradation environment of wastewater treatment, and photochemistry may have a greater effect than the biodegradation under sunlight, in which antibiotics are mainly photodegraded in the water environment; ibuprofen, iopromide and caffeine are more prone to biodegradation; esters and amides are the most common functional groups that are easily hydrolyzed in PPCPs[63], and tetracycline can undergo hydrolysis reactions due to adsorption into sediments. The factors affecting the degradation of PPCPs include pH, temperature, co-existing ions and dissolved organic matter, among which pH and temperature are the main factors affecting the degradation. Exploring the fate of PPCPs in the environment is the key to studying their distribution and environmental level, so it is necessary to analyze the degradation mode of PPCPs in a water environment to help further understand the degradation principle and behavior of PPCPs.　　Future research on PPCPs should be more in-depth and detailed. More emphasis will be placed on the water environment such as rain and sea water, which has been studied less before, to make the system more complete. The current research mainly focuses on the migration, transformation and toxic effects of PPCPs, and the toxic effects of degradation products need to be studied further. It is necessary to study the behavior, migration, transformation and toxic effects of PPCPs metabolites in the water environment, so as to provide basis for water environment pollution removal. In addition, the content of PPCPs in the water environment is very low, and the testing technology and instrument requirements are relatively strict. The existing analysis technology and instrument conditions need to be continuously improved to establish a more comprehensive and systematic testing system. [ABSTRACT FROM AUTHOR]

Doxorubicin (DRB) is an anthracycline oncogenic drug extracted from cultures of Streptomyces peucetius var. caesius. It is frequently recommended as an anti-neoplastic agent for the treatment of diverse malignancies. It exerts its antineoplastic effect either via inhibiting the enzyme topoisomerase II and/or via intercalation to DNA or reactive oxygen species generation. In the present article, the direct, simple, one-pot, somewhat eco-safe, and non-extractive spectrophotometric system was executed to track doxorubicin, a chemotherapeutic remedy, in the presence of paclitaxel, a naturally occurring Taxan antineoplastic radical, through the greenness rated method. DRB's optical density was studied in various mediums and solvents to develop the current approach. An acidic ethanolic solution was found to increase the optical density of the sample significantly. At 480 nm., the most remarkable optical density was obtained. Various experimental factors, including intrinsic media, solvent, pH, and stability time, were investigated and controlled. The current approach achieved linearity within the 0.6–40.0 µg mL-1 range, accompanied by a limit of both detection and quantification (LOD and LOQ) of 0.18 and 0.55 µg mL-1, correspondingly. The approach was validated under the ICH guidelines (Quality Guidelines). The system's greenness and enhancement degree were estimated. [ABSTRACT FROM AUTHOR]

Soybean straw reinforced Polylactic acid (PLA) composites were prepared by extrusion injection molding, the Box–Behnken experimental design method was used to obtain the optimal molding parameters, and the soil degradation behavior of composites was studied. Soil burial test was lasted 63 days, these composites were degraded in loam, clay and sand conditions, respectively. The weight loss rate, mechanical properties, fourier transform infrared spectroscopy, thermos-gravimetric and surface micromorphology were analyzed. After 63 days of soil burial test, the increased weight loss rate and the decreased mechanical properties indicated the weak interfacial adhesion, the change of infrared absorption peak illustrated that the degradation degree of fiber and matrix, and the appearance of voids and cracks showed the poor interfacial bonding quality. It is indicated that loam and clay conditions had a deeper influence on the degradation behavior of soybean straw/PLA composites than sand conditions. [ABSTRACT FROM AUTHOR]

In this paper, in order to achieve the development of a novel biodegradable dual-phase alloy in a Ca–Mg–Zn system, the establishment of the control strategy of degradation behavior of alloys composed of two phases was attempted by the control of alloy composition, constituent phases, and microstructure. By combining two phases with different dissolution behavior, biodegradable alloys are expected to exhibit multiple functions. For example, combining a suitable slow dissolving phase with a faster dissolving second phase may allow for dynamical concavities formation during immersion on the surface of the alloy, assisting the invasion and establishment of bone cells. Without the careful control of the microstructure, however, there is a risk that such dual-phase alloy rapidly collapses before the healing of the affected area. In this study, ten two-phase alloys consisting of various different phases were prepared and their degradation behaviors were examined. Consequently, it was found that by combining the IM3 and IM1 intermetallic phases with the compositions of Ca2Mg5Zn13 and Ca3Mg4.6Zn10.4, the expected degradation behavior can be obtained. [ABSTRACT FROM AUTHOR]