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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]

With the advancement of additive manufacturing (AM), customized vascular stents can now be fabricated to fit the curvatures and sizes of a narrowed or blocked blood vessel, thereby reducing the possibility of thrombosis and restenosis. More importantly, AM enables the design and fabrication of complex and functional stent unit cells that would otherwise be impossible to realize with conventional manufacturing techniques. Additionally, AM makes fast design iterations possible while also shortening the development time of vascular stents. This has led to the emergence of a new treatment paradigm in which custom and on-demand-fabricated stents will be used for just-in-time treatments. This review is focused on the recent advances in AM vascular stents aimed at meeting the mechanical and biological requirements. First, the biomaterials suitable for AM vascular stents are listed and briefly described. Second, we review the AM technologies that have been so far used to fabricate vascular stents as well as the performances they have achieved. Subsequently, the design criteria for the clinical application of AM vascular stents are discussed considering the currently encountered limitations in materials and AM techniques. Finally, the remaining challenges are highlighted and some future research directions are proposed to realize clinically-viable AM vascular stents. Vascular stents have been widely used for the treatment of vascular disease. The recent progress in additive manufacturing (AM) has provided unprecedented opportunities for revolutionizing traditional vascular stents. In this manuscript, we review the applications of AM to the design and fabrication of vascular stents. This is an interdisciplinary subject area that has not been previously covered in the published review articles. Our objective is to not only present the state-of-the-art of AM biomaterials and technologies but to also critically assess the limitations and challenges that need to be overcome to speed up the clinical adoption of AM vascular stents with both anatomical superiority and mechanical and biological functionalities that exceed those of the currently available mass-produced devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Link prediction is an important issue in social networks. Most of the existing methods aim to predict interactions between individuals for static networks, ignoring the dynamic feature of social networks. This paper proposes a link prediction method which considers the dynamic topology of social networks. Given a snapshot of a social network at time t (or network evolution between t 1 and t 2), we seek to accurately predict the edges that will be added during the interval from time t (or t 2) to a given future time t ′. Our approach utilizes three metrics, the time-varied weight, the change degree of common neighbor and the intimacy between common neighbors. Moreover, we redefine the common neighbors by finding them within two hops. Experiments on DBLP show that our method can reach better results. [ABSTRACT FROM AUTHOR]

Abstract: In order to improve the detection specificity of iron oxide nanoparticles (IONPs) delivered to tumors, we embedded saturation pulses into the sweep imaging using Fourier transformation (SWIFT) sequence to suppress long T2 tissues and fat. Simulation of the Bloch equation was first conducted to study behavior of the saturation pulses of various lengths under different T2 and off-resonance conditions. MR experiments were then conducted using in vivo mouse xenografts and a phantom consisting of IONPs, vegetable oil, and explanted tumor specimen, without and with long T2 suppression under a 7T magnetic field. For the in vivo study, arginine-glycine-aspartate (RGD) coated 10nm IONPs (RGD-IONPs) were delivered to tumors implanted in nude mice through both intra-tumor and intravenous injections. Histological studies confirmed that RGD-IONPs efficiently homed to tumors through RGD-integrin interaction. Compared to conventional SWIFT, the proposed method resulted in sufficient suppression on long T2 species but less influence on short T2 species. For both the in vivo and ex vivo studies, significantly improved contrast-to-noise ratio (CNR) was achieved between the IONPs and the long T2 species. [Copyright &y& Elsevier]

[Display omitted] • Four key effects of Cu addition on corrosion behavior of Zn-alloy are revealed. • Cu addition and rolling jointly alter the corrosion mode from localized to uniform. • Cold-rolled Zn–4Cu–0.02Li possesses proper mechanical and degradation properties. Zn–alloys are considered to be promising biodegradable materials due to suitable degradation rates. In this paper, novel Zn–Cu–Li alloys with layered CuZn 4 structure were achieved. The corrosion properties of newly developed biodegradable Zn–Cu–Li alloys in simulated body fluid was studied. Results indicated that the cold-rolled alloys presented a relatively uniform corrosion mode, although early corrosion occurred preferentially at phase boundaries. Galvanic corrosion and corrosion product films jointly determined the later corrosion process. Cu improved the corrosion potential and film properties in its solid solution state, induced galvanic corrosion, and provided a physical barrier to corrosion by forming CuZn 4 phase. Rolling accelerated the initial corrosion rate by enhancing the matrix electrochemical activity, while it contributed to uniform corrosion by improving the CuZn 4 phase shape. Finally, cold-rolled Zn–4Cu–0.02Li possessed the best corrosion resistance and mechanical properties combination among the prepared alloys, with a yield strength of 256 MPa, an ultimate strength of 342 MPa, a fracture elongation of 39.8 %, and a corrosion rate of nearly 55 μm/year. [ABSTRACT FROM AUTHOR]

A nitrogen-enriched active carbon fiber/reduced graphene oxide nanocomposite was synthesized by electrospinning, calcination, self-assembled reduction, and post treatment nitrogen doping. The nitrogen content and C/O ratio of nitrogen-enriched active carbon fiber/reduced graphene oxide nanocomposite was up to 12 at.% and 28 after post process N-doping, respectively. High specific capacitance of 208 F g −1 at 20 A g −1 and excellent rate performance was shown in 6 mol L −1 KOH. Meanwhile, a specific capacitance of 212 F g −1 was obtained at 3 A g −1 and along with 99% capacitance retention after 10 000 cycles for quasi solid state supercapacitors. The excellent electrochemical performance is attributed to unique line-plane structure between the one dimensional active carbon fiber and the two dimensional reduced graphene oxide, and incorporation of nitrogen functional groups. [ABSTRACT FROM AUTHOR]

Prussian blue analogues with tunable open channels are of fundamental and technological importance for energy storage systems. Herein, a novel facile synthesis of nickel-cobalt hexacyanoferrate/reduced graphene oxide (denoted as Ni-CoHCF/rGO) nanocomposite is realized by a reverse microemulsion method. The very fine Ni-CoHCF nanoparticles (10–20 nm) are homogeneously anchored on the surface of reduced graphene oxide by electrostatic adsorption and reduced graphene oxide is well-separated by Ni-CoHCF particles. Benefiting from the combined advantages of this structure, the Ni-. It CoHCF/rGO nanocomposite can be used as electrodes for both supercapacitors and sodium ion batteries exhibits excellent pseudocapacitve performance in terms of high specific capacitance of 466 F g −1 at 0.2 A g −1 and 350 F g −1 at 10 A g −1 , along with high cycling stabilities. As a cathode material for sodium ion batteries, it also demonstrates a high reversible capacity of 118 mAh g −1 at 0.1 A g −1 , good rate capability, and superior cycling stability. These results suggest its potential as an efficient electrode for high-performance energy storage and renewable delivery devices. [ABSTRACT FROM AUTHOR]

Polymer electrolytes based on electrospun polyimide (PI) membranes are incorporated with electrolyte solution containing 1molL−1 LiPF6/ethylene carbonate/ethylmethyl carbonate/dimethyl carbonate to examine their potential application for lithium ion batteries. The as-electrospun non-woven membranes demonstrate a uniformly interconnected structure with an average fiber diameter of 800nm. The membranes, showing superior thermal stability and flame retardant property compared to the commercial Celgard® membranes, exhibit high porosity and high uptake when activated with the liquid electrolyte. The resulting PI electrolytes (PIs) have a high ionic conductivity up to 2.0×10−3 S cm−1 at 25°C, and exhibit a high electrochemical stability potential more than 5.0V (vs. Li/Li+). They also possess excellent charge/discharge performance and capacity retention. The initial discharge capacities of the Li/PIs/Li4Ti5O12 cells are 178.4, 167.4, 160.3, 148.3 and 135.9 mAh g−1 at the charge/discharge rates of 0.2C, 1C, 2C, 5C and 10C, respectively. After 200 cycles at 5C, a capacity around ∼146.8 mAh g−1 can be still achieved. The PI-based polymer electrolytes with strong mechanical properties and good electrochemical performance are proved to be promising electrolytes for lithium ion batteries. [ABSTRACT FROM AUTHOR]

To couple strengthening with hydrogen-insensitive design in steels, many research employ nanosized carbides to trap hydrogen atoms from diffusion. Herein, by using the pearlite steel featuring with abundant ferrite and cementite interfaces as a model material, we show that by applying a moderate pre-strain on the ferrite/carbide interfaces, hydrogen trapping ability of these interfaces can be uniformly improved, considerably alleviating the hydrogen embrittlement while improving the tensile strength of the steel. Postmortem characterizations on the strained interfaces suggest that interfacial dislocations, carbon vacancies, and disconnections may be held accountable for restraining hydrogen uniformly on the interfaces; nevertheless, formation of slip bands upon large pre-strain localizes the above hydrogen traps at their intersections with the ferrite/carbide interfaces, deteriorating the hydrogen embrittlement resistance. The finding demonstrates a feasible method to tackle the trade-off between strength and hydrogen embrittlement resistance in steels. [Display omitted] [ABSTRACT FROM AUTHOR]

This study reports the effect of extracellular electron transfer (EET) on biomineralization mediated by Shewanella putrefaciens in damaged coatings under different carbon source conditions. S. putrefaciens was able to obtain energy from metal surfaces to support metabolism via EET when the carbon source was insufficient. Under these conditions, bacteria colonized the coating scratches, resulting in accelerated corrosion instead of mineralization. The EIS results revealed that biomineralization was most significant in the 75% carbon source medium after 7 days of incubation. Interestingly, the pH of the medium increased with an abundance of carbon sources, which promoted biomineralization. • Extracellular electron transfer affects biomineralization by S. putrefaciens in damaged coatings. • Corrosion instead of biomineralization is accelerated when carbon source is deficient. • Biomineralization is promoted and corrosion is suppressed when carbon source is sufficient. [ABSTRACT FROM AUTHOR]

Fluorescent carbon nanodots (CNDs) have exhibited attractive potential for biomedical applications due to their intriguing luminescent properties and good biocompatibility. One interesting property of CNDs is that they typically show different emission colors upon optical excitation using different wavelengths. However, it is still a challenge to obtain emissions covering the entire visible spectrum with comparable intensity with only one type of CND. Herein, CNDs with tunable full-color luminescence are successful prepared by a solvothermal approach, show broad absorption (200–700 nm) and fluorescence emission (nearly cover the entire visible region: from 400 to 700 nm) with comparable fluorescence intensities. The oxidation (o-CNDs) and reduction (r-CNDs) of CNDs surface would lead to the shifting of photoluminescence band into blue/green and red-light region, respectively. Further spectroscopic analyses and structural characterizations of CNDs (pristine state), o-CNDs (oxidation state) and r-CNDs (reduction state) demonstrate that O-related defect states (C O) and N-related defect states (C N) on surface of CNDs should be responsible for blue/green and red fluorescence emissions, respectively. Moreover, the CNDs are found to be biocompatible, as verified by in vitro cells assay and in vivo histological analysis. In vivo fluorescence imaging assay demonstrates that CNDs can be excreted through intestine and bladder system. The tunable full-color emission, good biocompatibility and metabolism suggest that the CNDs are promising fluorescent probes for biomedical applications. Carbon nanodots with tunable full-color luminescence can be controlled by oxygen/nitrogen-related surface state, and can serve as optical fluorescence nanoprobes in multicolor bio-imaging. Image 1 [ABSTRACT FROM AUTHOR]

Abstract Aim Colorectal cancer (CRC) is a common human malignancy which accounts for 600,000 deaths annually at the global level. Soyasapogenol B (Soy B), an ingredient of soybean, has been found to exert anti-proliferative activities in vitro in human breast cancer cells. The current study aimed to evaluate the efficacy of Soy B in suppressing CRC. Methods and materials The effect of Soy B on cell viability was assessed using the Cell Counting Kit-8 (CCK-8) assay. The effect of Soy B on cell proliferation was determined using colony formation assay. The percentage of apoptotic cells was determined by the TUNEL assay and flow cytometry following Annexin V-FITC/Propidium Iodide (PI) double staining. JC-1 staining was performed to examine the change in mitochondrial membrane potential. Autophagy was examined by acridine orange staining and mRFP-GFP-LC3 adenovirus transfection. Caspase-12 activities were determined by ELISA kit. Western blotting was used to determine the expression of relevant proteins. To investigate the role of autophagy in the pro-death and pro-apoptotic activities of Soy B, autophagy inhibitors Bafilomycin A1 (Baf-A1) and Atg5 siRNA were utilized. TUDCA and CHOP shRNA were utilized to block ER stress. Moreover, a CRC xenograft murine model was used to analyze the therapeutic efficacy of Soy B in vivo. Key findings Soy B treatment decreased the number of viable cells and colonies formed in CRC cell lines. Moreover, Soy B treatment promoted the apoptotic cell death via the intrinsic pathway and autophagy which positively contributed to cell death and apoptosis. In addition, our results showed that ER stress, triggered by Soy B, mediated apoptosis and autophagy. In vivo results revealed that Soy B could suppress tumor growth, which was associated with increased ER stress, accompanied with apoptosis and autophagy induction. Significance Soy B was able to promote cell death in vitro and in vivo. Our findings highlight the possibility of utilizing Soy B as a chemotherapeutic agent to prevent and treat CRC. [ABSTRACT FROM AUTHOR]

Highlights • Cognition-related white matter (WM) microstructure was disrupted in AD patients. • FA and MD values of cognition related WM tracts were correlation with MMSE scores. • Accuracy of SVM trained by white matter tract features could reach 91.67%. • MD value of cingulum was the most important feature. Abstract Alzheimer's disease (AD) is a worldwide progressive neurodegenerative disorder in the elderly. Previous research has indicated that Alzheimer's disease impairs white matter (WM) tracts. Anatomical and neuroimaging studies have indicated that WM tracts are associated with cognitive function. Whether the abnormal WM integrity in AD is associated with cognitive impairments and the clinical symptoms is still not clear. To this end, we investigated the relationship between the impairments in WM tracts and the decline of cognitive ability in AD. Diffusion tensor imaging (DTI) data were collected from 38 AD patients and 30 normal, cognitively healthy volunteers. The tract-based spatial statistics (TBSS) approach was used to compare the fractional anisotropy (FA) and mean diffusivity (MD) values between the two groups. WM tracts (cingulum, superior longitudinal fasciculus (SLF), uncinate fasciculus (UF), and inferior longitudinal fasciculus (ILF)) associated with cognition function were extracted for region of interest (ROI)-based analysis. Significantly decreased FA values and increased MD values of the cognition-related WM tracts were observed in the AD group compared with the normal cognition (NC) group. In addition, we further demonstrated that the decreased FA values and increased MD values of the cognition-related WM tracts were significantly correlated with MMSE scores. These results indicated that abnormal changes in WM integrity are observed following AD. Finally, we used support vector machine (SVM) with a repeated, stratified 10-fold cross-validated classifier to evaluate the ability of FA and MD values to discriminate disease. The accuracy of the SVM using cognition-related WM as classified features was higher than that using non-cognition-related tracts. Most importantly, our results showed the relationship between abnormal WM tracts and cognitive ability in AD. These findings further suggested that AD-related impairments in cognition-related WM tracts may influence the cognitive ability of AD patients. [ABSTRACT FROM AUTHOR]

A handful of previous studies have reported the association between exposure to outdoor artificial light at night (ALAN) and sleep problems. However, evidence for such association is limited in low- and middle-income countries. This study aimed to examine the association between outdoor ALAN exposure and sleep quality in veterans across different regions of China. Within the network of the Chinese Veteran Clinical Research Platform, we selected 7258 participants from 277 veteran communities in 18 cities across China during December 2009 and December 2011, using a multi-stage stratified cluster sampling strategy. Face-to-face interviews with the participants were conducted by trained investigators. We used the Pittsburgh Sleep Quality Index (PSQI) to assess participants' sleep quality. We defined poor sleep quality as a PSQI global score >7. The 3-year average exposure to outdoor ALAN prior to the baseline interview was calculated using satellite imagery data, according to participants' geolocation information. The association of ALAN exposure with sleep quality was examined using the mixed-effects logistic regression models with natural cubic splines. The exposure-response curve for sleep quality associated with ALAN exposure was nonlinear, with a threshold value of 49.20 nW/cm2/sr for the 3-year average exposure to outdoor ALAN prior to the baseline interview. Higher ALAN exposure above the threshold was associated with increased risk of poor sleep quality. After adjusting for potential confounders, the odds ratios (and 95%CI, 95% confidence intervals) were 1.15 (0.97, 1.36) and 1.45 (1.17, 1.78) at the 75th and 95th percentiles of ALAN against the threshold. The association of ALAN exposure with poor sleep quality was more pronounced in veterans with depression than those without. Higher OR of poor sleep quality at the 75th percentile of ALAN against the threshold was observed in veterans with depression than those without [2.09 (1.16, 3.76) vs. 1.09 (0.92, 1.30)]. Long-term exposure to outdoor ALAN was associated with higher risk of poor sleep quality in Chinese veterans. Effective outdoor ALAN management may help to reduce the burden of sleep disorders in Chinese veterans. [Display omitted] • This is the first study on light at night and sleep quality in Chinese veterans. • The threshold effect for sleep quality associated with light exposure was observed. • Higher light exposure was associated with higher risk of poor sleep quality. [ABSTRACT FROM AUTHOR]

Purpose Polycystic ovary syndrome (PCOS) is a metabolic and endocrinal disorder affecting a number of women of reproductive age. We aimed to reveal the correlation between the endocannabinoid system and PCOS, which may provide a new therapeutic target for PCOS treatment. Methods Serum levels of anandamide and 2-arachidonoylglycerol andexpression of cannabinoid receptors and fatty acid amide hydrolase (FAAH) in the endometrium were compared between women with PCOS and infertile women without PCOS, as well as women with PCOS before and after treatment with Diane-35 and metformin. Cannabinoid receptors and FAAH in the endometrium were stained using the immunohistochemical method. Results were analyzed by calculating integrated optical density. Findings Plasma anandamide was increased significantly in women with PCOS compared with infertile women without PCOS. Treatment with Diane-35 and metformin reversed this increase in women with PCOS. No significant difference in 2-arachidonoylglycerol was observed between the infertile women with or without PCOS. The women with PCOS had lower endometrial expression of FAAH compared with infertile women without PCOS, whereas no significant difference in endometrial expression of cannabinoid receptors was observed between the women with PCOS and infertile women without PCOS. We found that after treatment with Diane-35 and metformin, FAAH expression tended toward a significant increase compared with women before the treatment. Implications Endocannabinoid system may be involved in the progression of PCOS, and serum anandamide could serve as a potential biomarker of clinical diagnosis of PCOS. [ABSTRACT FROM AUTHOR]

Irradiation-assisted stress corrosion cracking normally initiates and propagates along grain/phase boundaries. Here, by using scanning Kelvin probe force microscopy, we characterized the Volta potential difference (VPD) changes prior and after proton irradiation at austenite/carbide (γ/C), ferrite/carbide (δ/C) and austenite/ferrite (γ/δ) interfaces in a 308 L stainless steel. It was found that, prior to irradiation, γ/C boundary had the lowest VPD, followed by δ/C and γ/δ. VPDs of all three types of phase boundaries slightly decreased after proton irradiation, wherein the γ/C boundary showed the largest VPD drop, followed by δ/C and γ/δ. The γ/C interface demonstrates the highest tendency of corrosion. [Display omitted] • The role of carbides at phase boundaries on IASCC is evaluated. • Irradiation promotes corrosion at γ/C, δ/C and δ/γ interfaces. • The γ/C interface shows the lowest Volta potential and even more so upon irradiation. • The Cr content seems to dominate the corrosion tendency evolution at all types of interfaces. [ABSTRACT FROM AUTHOR]

Abstract: Alzheimer's disease (AD), the most common cause of dementia, is thought to be a progressive neurodegenerative disease that is clinically characterised by a decline of memory and other cognitive functions. Mild cognitive impairment (MCI) is considered to be the prodromal stage of AD. However, the relationship between AD and MCI and the development process remains unclear. The amygdala is one of the most vulnerable structures in the early stages of AD. To our knowledge, this is the first report on the alteration of the functional connectivity of the amygdala in AD and MCI subjects. We hypothesised that the amygdala-cortical loop is impaired in AD and that these alterations relate to the disease severity. In our study, we used resting-state functional MRIs to investigate the altered amygdala connectivity patterns in 35 AD patients, 27 MCI patients and 27 age- and gender-matched normal controls (NC). Compared with the NC, the decreased functional connectivity found in the AD patients was mainly located between the amygdala and the regions that are included in the default mode, context conditioning and extinction networks. Importantly, the decreased functional connectivity between the amygdala and some of the identified regions was positively correlated with MMSE, which indicated that the cognitive function impairment is related to an altered functional connectivity pattern [Copyright &y& Elsevier]

Objective: N270, an endogenous ERP component of conflict effect, was evoked in previous studies with S1–S2 paradigm. The present experiment is designed to confirm the speculation that this conflict-related negativity could also be elicited by stimulus probes having conflict with a memorized item in a visual post-retrieval comparison task.Methods: A Sternberg probe-matching paradigm was modified in the present study. The stimuli consisted of a memory set of 3 different items (simple figures) and a retrieval set of 3 probe figures. Subjects matched each probe to its corresponding item in the memory set. The tasks were designed with different conflict loads of no-conflict, low-conflict and high-conflict in the probe retrieval test.Results: Probes of no-conflict elicited a major positive going component, P300, with bilateral parietal distribution. Probes of low- and high-conflict evoked N270, while N430 was elicited only in high-conflict condition. N270 was more negative in high-conflict condition than in low-conflict condition. The N270 was right hemispheric prominent in the low-conflict task and remarkably distributed over the right prefrontal areas. On the other hand, both N270 and N430 were distributed bilaterally on the scalp in the high-conflict task.Conclusions: The present results demonstrate that the N270 is an index to the conflict identification, while the N430 of the high-conflict task reflects the processing for complex conflicts following probe retrieval. These negativities are related to the processing of conflicts. [Copyright &y& Elsevier]

• Composite structures consisting of nano-ripples and grooves are fabricated. • The adhesion of E. coli was limited on nano-ripples and micro-grooves. • Deep grooves are conducive to the deformation and rupture of bacteria. • All types of nano-ripples surfaces present good biocompatibility. Structured surfaces with both anti-bacterial capability and biocompatibility are essential to medical devices including orthopedic implants. Over the past few years, numerous studies indicated that nanostructures such as nanotubes, nanowires, nano-pillars and nano-ripples were capable of repelling or killing bacteria, while the morphology and dimensions of the nanostructures showed essential influence on the adhesion and proliferation of cells. The long-term functionalities of implants depend on their reliable anti-bacterial performance at the same time enhanced biocompatibility. However, researches covering both these two aspects are still very limited. In this paper, we applied one-step femtosecond laser irradiation to produce three types of nano-ripples, and to investigate their anti-bacterial behavior and their biocompatibility. Our results demonstrate that all the three types of nano-ripples are capable of preventing bacterial colonization and biofilm formation, with their anti-bacteria rates towards E. coli respectively 43%, 49% and 56%. Meanwhile, the femtosecond laser induced nano-ripples exhibit good rat mesenchymal stem cells (MSCs) proliferation capacity and spreading performance, and the nano-ripples affect significantly the orientation of MSCs. The results offer valuable information and potentials on the anti-bacteria and biocompatibility of nanostructures. [ABSTRACT FROM AUTHOR]

Rapid corrosion of biodegradable magnesium alloys under in vivo condition is a major concern for clinical applications. Inspired by the stability and biocompatibility of titanium oxide (TiO 2) passive layer, a functionalized TiO 2 /Mg 2 TiO 4 nano-layer has been constructed on the surface of WE43 magnesium implant by using plasma ion immersion implantation (PIII) technique. The customized nano-layer not only enhances corrosion resistance of Mg substrates significantly, but also elevates the osteoblastic differentiation capability in vitro due to the controlled release of magnesium ions. In the animal study, the increase of new bone formation adjacent to the PIII-treated magnesium substrate is 175% higher at post-operation 12 weeks, whereas the growth of new bone on titanium control and untreated magnesium substrate are only 97% and 29%, respectively. In addition, its Young's modulus can be restored to about 82% as compared with the surrounding matured bone. Furthermore, this specific TiO 2 /Mg 2 TiO 4 layer even exhibits photoactive bacteria disinfection capability when irradiated by ultraviolet light which is attributed to the intracellular reactive oxygen species (ROS) production. With all these constructive observations, it is believed that the TiO 2 /Mg 2 TiO 4 nano-layer on magnesium implants can significantly promote new bone formation and suppress bacterial infection, while the degradation behavior can be controlled simultaneously. Image 1 [ABSTRACT FROM AUTHOR]