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Introduction: Multi-channel electrophysiology systems for recording of neuronal activity face significant data throughput limitations, hampering real-time, data-informed experiments. These limitations impact both experimental neurobiology research and next-generation neuroprosthetics., Methods: We present a novel solution that leverages the high integration density of 22nm fully-depleted silicon-on-insulator technology to address these challenges. The proposed highly integrated programmable System-on-Chip (SoC) comprises 68-channel 0.41 μW/Ch recording frontends, spike detectors, 16-channel 0.87-4.39 μW/Ch action potentials and 8-channel 0.32 μW/Ch local field potential codecs, as well as a multiply-accumulate-assisted power-efficient processor operating at 25 MHz (5.19 μW/MHz). The system supports on-chip training processes for compression, training, and inference for neural spike sorting. The spike sorting achieves an average accuracy of 91.48 or 94.12% depending on the utilized features. The proposed programmable SoC is optimized for reduced area (9 mm 2 ) and power. On-chip processing and compression capabilities free up the data bottlenecks in data transmission (up to 91% space saving ratio), and moreover enable a fully autonomous yet flexible processor-driven operation., Discussion: Combined, these design considerations overcome data-bottlenecks by allowing on-chip feature extraction and subsequent compression., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Guo, Weiße, Zeinolabedin, Schüffny, Stolba, Ma, Wang, Scholze, Dixius, Berthel, Partzsch, Walter, Ellguth, Höppner, George and Mayr.)

Decision making is critical in our daily lives and for society in general and is finding evermore practical applications in information and communication technologies. Herein, we demonstrate experimentally that single photons can be used to make decisions in uncertain, dynamically changing environments. Using a nitrogen-vacancy in a nanodiamond as a single-photon source, we demonstrate the decision-making capability by solving the multi-armed bandit problem. This capability is directly and immediately associated with single-photon detection in the proposed architecture, leading to adequate and adaptive autonomous decision making. This study makes it possible to create systems that benefit from the quantum nature of light to perform practical and vital intelligent functions.

Cardiovascular diseases have been the leading cause of global mortality and disability. In addition to traditional drug and surgical treatment, more and more studies investigate tissue engineering therapeutic strategies in cardiovascular medicine. Collagen interweaves in the form of trimeric chains to form the physiological network framework of the extracellular matrix of cardiac and vascular cells, possessing excellent biological properties (such as low immunogenicity and good biocompatibility) and adjustable mechanical properties, which renders it a vital tissue engineering biomaterial for the treatment of cardiovascular diseases. In recent years, promising advances have been made in the application of collagen materials in blood vessel prostheses, injectable cardiac hydrogels, cardiac patches, and hemostatic materials, although their clinical translation still faces some obstacles. Thus, we reviewed these findings and systematically summarizes the application progress as well as problems of clinical translation of collagen biomaterials in the cardiovascular field. The present review contributes to a comprehensive understanding of the application of collagen biomaterials in cardiovascular medicine. [ABSTRACT FROM AUTHOR]

Additive Manufacturing (AM) has revolutionized the production industry by offering design freedom with shorter lead times and reduced material wastage. However, the damage tolerance (DT) of AM parts is a significant concern due to their microstructural and geometric complexities, which affect their mechanical performance. This article aims to provide a comprehensive overview of the manufacturing parameters affecting the components produced by AM specifically selective laser melting (SLM). Detailed discussions are presented on the effects of manufacturing attributes on the microstructure, defects, and mechanical characteristics of AM parts. Depending on these aspects, basic concepts are studied and critically explained specifically for AM materials. The basic criterion for damage‐tolerant component design, the criterion for fatigue and fracture properties, and the effect of the defects on fatigue life are critically presented. In addition, the effect of different types of gradation on the crack growth behavior of samples processed by SLM is also investigated in depth. There is currently a lack of a specific review study in the literature that establishes a connection between process attributes and metallographic properties, and their impact on the damage behavior of additively manufactured parts. This gap in research highlights the need for a comprehensive review to bridge this knowledge deficit and provide valuable insights for understanding the relationships between manufacturing processes, material characteristics, and the structural integrity of additively manufactured components. This review concludes by addressing the challenges and opportunities in designing and qualifying AM parts for damage tolerance. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a prevalent neurodegenerative disease in which treatment often includes an exercise regimen. Exercise is neuroprotective in animal models of PD, and, more recently, human clinical studies have verified exercise's disease-modifying effect. Aerobic exercise and resistance training improve many of PD's motor and non-motor symptoms, while neuromotor therapy and stretching/flexibility exercises positively contribute to the quality of life in people with PD. Therefore, understanding the role of exercise in managing this complex disorder is crucial. Exerkines are bioactive substances that are synthesized and released during exercise and have been implicated in several positive health outcomes, including neuroprotection. Exerkines protect neuronal cells in vitro and rodent PD models in vivo. Aerobic exercise and resistance training both increase exerkine levels in the blood, suggesting a role for exerkines in the neuroprotective theory. Many exerkines demonstrate the potential for protecting the brain against pathological missteps caused by PD. Every person (people) with Parkinson's (PwP) needs a comprehensive exercise plan tailored to their unique needs and abilities. Here, we provide an exercise template to help PwP understand the importance of exercise for treating PD, describe barriers confronting many PwP in their attempt to exercise, provide suggestions for overcoming these barriers, and explore the role of exerkines in managing PD. In conclusion, exercise and exerkines together create a powerful neuroprotective system that should contribute to slowing the chronic progression of PD. [ABSTRACT FROM AUTHOR]

Encapsulating antiepileptic drugs (AEDs), including ethosuximide (Etho), into nanoparticles shows promise in treating epilepsy. Nanomedicine may be the most significant contributor to addressing this issue. It presents several advantages compared to traditional drug delivery methods and is currently a prominent area of focus in cancer research. Incorporating Etho into bismuth ferrite (BFO) nanoparticles within diverse controlled drug delivery systems is explored to enhance drug efficacy. This approach is primarily desired to aid in targeted drug delivery to the brain's deepest regions while limiting transplacental permeability, reducing fetal exposure, and mitigating associated adverse effects. In this investigation, we explored Etho, an antiepileptic drug commonly employed for treating absence seizures, as the active ingredient in BFO nanoparticles at varying concentrations (10 and 15 mg). Characterization of the drug-containing BFO nanoparticles involved scanning electron microscopy (SEM) and elemental analysis. The thermal properties of the drug-containing BFO nanoparticles were evaluated via differential scanning calorimetry (DSC) analysis. Cytotoxicity evaluations using the MTT assay were conducted on all nanoparticles, and human neuroblastoma cell line cultures (SH-SY5Y) were treated with each particle over multiple time intervals. Cell viability remained at 135% after 7 days when exposed to 15 mg of Etho in BFO nanoparticles. Additionally, in vitro drug release kinetics for Etho revealed sustained release lasting up to 5 hours with a drug concentration of 15 mg. [ABSTRACT FROM AUTHOR]

Background: Hypertension is a significant chronic disease globally, and lifestyle modifications are crucial for the prevention of this disease. We conducted a longitudinal analysis of the associations between lifestyle factors and the incidence of hypertension, stratified by sociodemographic characteristics. Methods: We analyzed 113,022 adults (65,315 men), aged 20 years or older from the Korean National Health Insurance Service-National Sample Cohort 2.0 who participated in health screening between 2002 and 2003. Lifestyle factors (smoking, drinking, physical activity) were assessed at baseline using self reports, and incident hypertension was defined based on physician diagnoses. Cox proportional hazards regression models were used to assess associations. Results: During an 11.6-year follow-up, 26,812 new cases of hypertension were identified. The risk of hypertension was high among men and women who smoked over 20 cigarettes daily (men: hazard ratio [HR]: 1.15; 95% confidence interval [CI], 1.08–1.21; women: HR: 1.62; 95% CI 1.17–2.25) and those who drank over 1.5 bottles of alcohol daily (men, HR: 1.18; 95% CI, 1.12–1.24; women, HR: 1.23; 95% CI 1.02–1.47). These associations tended to be high in high-income men (HR: 1.09; 95% CI, 1.04–1.14), low-income women (HR: 1.19; 95% CI, 1.05–1.35) and non-obese women (HR: 1.13; 95% CI, 1.01–1.27) who currently smoked. Physical activity was inversely associated with incident hypertension in men (HR: 0.96; 95% CI, 0.93–0.99). Conclusions: Unhealthy lifestyle factors, such as heavy smoking and drinking, was associated with an increased risk of hypertension, with variations by income, BMI, and sex. These findings underscore the importance of tailored, population-specific prevention strategies to address hypertension disparities. [ABSTRACT FROM AUTHOR]

Training helps to maintain and improve sufficient muscle function, body control, and body coordination. These are important to reduce the risk of fracture incidents caused by falls, especially for the elderly or people recovering from injury. Virtual reality training can offer a cost-effective and individualized training experience. We present an application for the HoloLens 2 to enable musculoskeletal training for elderly and impaired persons to allow for autonomous training and automatic progress evaluation. We designed a virtual downhill skiing scenario that is controlled by body movement to stimulate balance and body control. By adapting the parameters of the ski slope, we can tailor the intensity of the training to individual users. In this work, we evaluate whether the movement data of the HoloLens 2 alone is sufficient to control and predict body movement and joint angles during musculoskeletal training.We record the movements of 10 healthy volunteers with external tracking cameras and track a set of body and joint angles of the participant during training. We estimate correlation coefficients and systematically analyze whether whole body movement can be derived from the movement data of the HoloLens 2. No participant reports movement sickness effects and all were able to quickly interact and control their movement during skiing. Our results show a high correlation between HoloLens 2 movement data and the external tracking of the upper body movement and joint angles of the lower limbs. [ABSTRACT FROM AUTHOR]

Currently, an increasing number of Chinese urban citizens are participating in daily physical exercise. Existing research has shown that physical exercise can increase life satisfaction. However, some studies also suggest that the relationship between the two is unstable. The purposes of this study are to examine physical exercise and to test its correlation with life satisfaction of urban residents in China. Data are obtained from the 2018 China Family Panel Studies, and we focus on urban residents. Our overall sample size is 7423 people, including 3641 females (49.05%) and 3782 males (50.95%), with an average age of 49.55 years old. Because the dependent variables are continuous variables, the multiple linear regression model is used for data analysis. We find that the life satisfaction of Chinese urban residents is on the high side. Our core discovery is that there is a significant positive relationship between the frequency and duration of physical exercise and life satisfaction. Our further discovery is that the frequency of physical exercise affects life satisfaction by influencing popularity and positive emotions. Similarly, the duration of physical exercise affects life satisfaction by influencing popularity and positive emotions. Whether it is the frequency or the duration of physical exercise, it can reflect the residents' attention to physical exercise. Physical exercise habits not only promote physical health by strengthening physical fitness but also promote mental health by alleviating depression and promote social communication by increasing social activities in the Chinese context. All of these can improve people's life satisfaction. Our research suggests that the improvement in life satisfaction not only needs the abundance of external material conditions but also needs the individual to improve their physical and mental health through physical exercise. [ABSTRACT FROM AUTHOR]

Introduction: Physical activity (PA) and exercise (EX) participation rates have not been increasing among older adults, with many not meeting recommended guidelines. This qualitative descriptive study examined factors influencing engagement in PA within and outside an older adult fitness club context, using self-determination theory (SDT). Methods: Thirty-seven community-dwelling adults 65 years and older participated in focus groups or telephone interviews. Two researchers independently coded and analyzed transcript data inductively and deductively using SDT. Results: Two broad themes, The Spectrum of Motivating Factors and Facilitators and Barriers, and nine sub-themes, Physical Activity and Exercise Brings Me Joy; Meaningful Personal Impetuses; I Get Active with a Little Help from my Spouse and Others; I See Changes and Improvements (Theme 1); I Can Do This; Connections and Sense of Belonging; I Cannot Do This; Setting, Environment, and People Supports; and Pragmatics (Theme 2), emerged from the data. All participants discussed several motivating factors: enjoyment, managing health conditions, being held 'to account' by others, opportunities for socialization, and seeing improvements in health and well-being. A lack of supportive environments, knowledgeable staff and suitable settings and programs were cited as barriers by participants who were not older adult fitness club members. Discussion: Factors along the extrinsic to intrinsic regulation continuum facilitated or hindered community-dwelling older adults to engage in and sustain PA within and outside an older adult fitness club context. The findings underscore the need for programs, settings, environments, and related components to be expressly older-adult-tailored to enhance motivation through competence, autonomy, and relatedness support for maximal engagement and participation in PA or EX. [ABSTRACT FROM AUTHOR]

To validate range shifts in proton therapy, we investigated the potential of using the temporal information of prompt gamma rays as an indicator. We simulated the proton transport process using Monte Carlo simulations and used a geometric scorer to obtain the location and timing of prompt gamma ray production. By using a homogeneous target material in the simulation model, we established a fitted relationship between the range of 90-210 MeV protons and the corresponding temporal spectral width. Additionally, by introducing air cavities of 2-20 mm in simulations of inhomogeneous target materials, we observed significant correlations between the range offsets and the temporal spectral widths. These correlations were fitted to derive a functional relationship between the two variables. [ABSTRACT FROM AUTHOR]

In recent years, the incidence of chronic pancreatitis has increased significantly. Pancreatic calculi obstruct the pancreatic duct and induce abdominal pain in the patients. Pancreatic duct stenting is the major treatment option for chronic pancreatitis with calculi. In this study, a new kind of drug-eluting stent, a pancreatic stent coated by methacrylated gelatin (GelMA) hydrogel loaded with citric acid (CA), was designed for the interventional treatment of pancreatic duct calculi. The CA loading capacity reached up to 0.7 g CA/g hydrogel-coated stent. The GelMA hydrogel coating has higher mechanical strength and lower swelling performance after loading with CA. The in vitro experiments of stents exhibited good performance in CA sustained release and the calculi can be dissolved in almost 3 days. The stents also showed good blood compatibility and cell compatibility. This research has important clinical value in the treatment of chronic pancreatitis with pancreatic calculi. [ABSTRACT FROM AUTHOR]

Background: Population aging is a global trend, and the number of older adults living alone is increasing. Tai chi, a traditional Chinese exercise, has been shown to improve the physical and mental health of older adults. Aim: To investigate the effects of tai chi on death anxiety in older adults living alone and the role of social support and psychological capital in this relationship. Method: A cross-sectional study of 493 older adults living alone in four cities in southwestern China. Participants were assessed using questionnaires on tai chi practice, social support, psychological capital, and death anxiety. Results: Tai chi practice significantly reduced death anxiety in older adults living alone. It also positively correlated with social support and psychological capital, both of which negatively correlated with death anxiety. Social support and psychological capital mediated the relationship between tai chi practice and death anxiety, suggesting that tai chi may reduce death anxiety through these factors. These findings encourage older adults living alone to practice tai chi, as it may improve their mental and physical health and reduce their risk of death anxiety. Conclusion: Tai chi practice may reduce death anxiety in older adults living alone through the chain-mediated effects of social support and psychological capital. This suggests that tai chi may be a beneficial intervention for older adults living alone. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic negatively influenced individuals' physical activity levels (PALs) and particularly the PAL of the elderly. However, few studies have examined the correlates of PALs in this population during the pandemic. This study aimed to evaluate the residence-specific correlates of PALs in elderly people from Croatia and Bosnia and Herzegovina during the COVID-19 pandemic. The participants were 211 persons older than 65 years (101 females), of whom 111 were community-dwelling residents, and 110 were nursing home residents (71.11 ± 3.11 and 72.22 ± 4.01 years of age, respectively; t-test = 0.91, p < 0.05). The variables included health status, residential status sociodemographic factors, anthropometrics (body mass, height, and body mass index), and PAL. PAL was evaluated using a translated version of the Physical Activity Scale for the Elderly (PASE), and was validated in this study. PASE showed good test–retest reliability (51% of the common variance) and validity (57% of the common variance, with the step count measured using pedometers). Apart from participants' health status and age, PAL was positively correlated with (i) community-dwelling residence (OR = 1.93, 95% CI: 1.60–2.23), and (ii) a lower BMI (OR = 0.85, 95% CI = 0.71–0.98). The pre-pandemic physical activity was positively correlated with the PAL of the nursing home residents (OR = 1.2, 95% CI: 1.02–1.45). A higher education level was positively correlated with the PAL of community-dwelling residents (OR = 1.31, 95% CI: 1.04–1.66). This study evidenced the residence-specific correlates of PALs, and enabled the identification of specific groups that are at risk of having low PALs during the pandemic. Future studies examining this problem during a non-pandemic period are warranted. [ABSTRACT FROM AUTHOR]

A phytochorological and ecobiological study of the nine species, two subspecies and two varieties of the genera Aeonium and Greenovia in La Gomera is carried out, with special attention to F1 hybridization in nature. To the ten hybrids already described on the island, seven new hybrids were discovered, which are the subject of a separate publication. In all the known hybrids I determined whether the parents were sympatric or allopatric. The geographical coincidence of the parents was a sine qua non requirement for hybridization to occur in all the hybrids known so far, since pollen transfer by biotic and abiotic agents does not function between disjunct areas. The two prezygotic reproductive barriers that currently prevent interspecific hybridization in Aeonium or intergeneric hybridization between Aeonium and Greenovia are the geographic separation of populations and the different flowering times. The ability to survive and reproduce successfully of F1 hybrids in Aeonium and Greenovia is usually lower than that of the parent species and they generally disappear from the environment in the first filial generation without leaving offspring. The fundamental principles that govern F1 hybridization in La Gomera are extracted, and after verifying that they were also fulfilled in the other mountainous islands, they were synthesized in eight principles, which provide an updated vision of hybridization in the genus Aeonium. Citation: Arango O. 2024: Principles governing F1 hybridization in the genera Aeonium and Greenovia in La Gomera, Canary Islands. – Willdenowia 53: 257–268 Version of record first published online on 23 January 2024. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the associations of social support factors with leisure-time physical activity (LTPA) of older people in Fuwen village. A cross-sectional study included 523 randomly selected elderly people (60+ years) whose LTPA levels were determined using the shortened version of the International Physical Activity Questionnaire (IPAQ-S). A modified version of the Physical Activity Social Support Scale (PASSS) was operated to gather perceived scores of the social support factors. A multivariate linear regression was performed to locate associations of perceived scores of social supports with leisure-time walking (LTW) and moderate and vigorous physical activity (MVPA). The results indicated that social support from family was positively and significantly related to LTW and MVPA in both models. The community factor was positively and significantly correlated with MVPA in both models. The sport club factor was related to LTW and MVPA to some extent. The results suggest that social support from family is the most important motivator for older people's LTW and MVPA in the village of Fuwen. Social support from the community is the motivator for older people's MVPA. The sport club factor has some effects on older people's LTW and MVPA as well. More future studies are needed to extend the database of the relationship between social support and rural older people's physical activity. [ABSTRACT FROM AUTHOR]

This retrospective observational study describes the results of an ad-hoc designated prevention protocol aimed at containing the spread of the scabies infestation among healthcare workers (HCWs) of a large University Hospital in Italy. The outbreak started on October 2022 and a preventive protocol was set up thanks to a multidisciplinary approach. HCWs at high scabies risk were defined as subjects working in Operative Units with a scabies prevalence higher than 2%, close contacts of a confirmed case of scabies, or HCWs with signs and symptoms of the disease. All cases at high scabies risk underwent a dermatological examination, and the infested HCWs were suspended from work until definitive healing. Mass drug administration was established for all HCWs working in Operative Units with a scabies prevalence higher than 2%. Until March 2023, out of 183 screening dermatological examinations, 21 (11.5%) were diagnostic for scabies. Between 11 October 2022 (date of the first diagnosed scabies case) and 6 March 2023 (the end of incubation period related to the last case detected), the frequency of scabies was 0.35% (21 scabies cases/6000 HCWs). The duration of the outbreak in our hospital was 14.7 weeks. Statistical analysis shows a significant association between scabies and being a nurse and having an allergy to dust mites. We obtained a low frequency of scabies infection, limiting the duration of the outbreak and the related economic burden. [ABSTRACT FROM AUTHOR]

(1) Background: Green and open spaces are conducive to physical activity for the elderly. However, it is unclear how different landscape characteristics relate to the physical activity of the elderly. (2) Methods: following the PRISMA method, this study reviewed the existing literature on the landscape characteristics correlated with the elderly's physical activity (PA) from Web of Science, Scopus, and PubMed. We conducted a systematic full-text review of 25 eligible reports and studies related to the linkage between the characteristics of green and open spaces and the elderly's physical activity (PA); (3) Results: Nature/greenery, safety, road/path conditions, aesthetics, PA facilities, accessibility, amenity, water, and elderly accessibility facilities were found to be positively associated with elderly's PA. Pavement conditions (gravel), the presence of water, poor maintenance, neighborhood aesthetics, and GVI are negatively correlated with the elderly's PA; (4) Conclusions: We close the paper by making a few recommendations for future policy-making, practice, and research. It is suggested that the landscape characteristics be applied in evidence-based policy-making and design, and in tackling health inequality. Future research should be more specific about the impact of site-scale factors, include landscape characteristics specifically needed by the elderly to conduct PA, and involve a wider scope of green and open space on top of neighborhood green and open space and parks. Additionally, these studies should take into consideration different cultural settings and geographical scales to reveal the different effects of various aspects of green and open space. [ABSTRACT FROM AUTHOR]

This work analyses damage formation within the bulk of basalt fiber-reinforced polymers (BFRP) by means of open-source Digital Volume Correlation (DVC). Volumetric image data were obtained from conventional in-situ X-Ray computed micro-tomography (µCT) of samples loaded in tension. The open-source image registration toolkit Elastix was employed to obtain full 3D displacement fields from the image data. We assessed the accuracy of the DVC results using the method of manufactured solution and showed that the approach followed here can detect deformation with a magnitude in the order of a fiber diameter which in the present case is 17 µm. The beneficial influence of regularization on DVC results is presented on the manufactured solution as well as on real in-situ tensile testing CT data of a BFRP sample. Results of the correlation showed that conventional µCT equipment in combination with DVC can be used to detect defects which could previously only be visualized using synchrotron facilities or destructive methods. [ABSTRACT FROM AUTHOR]

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BACKGROUND: There is limited evidence for emergency physicians and emergency trauma surgeons regarding the determinants of early and rapid assessment of older adult in-hospital mortality due to earthquakes. This study explored factors related to the early and rapid assessment of the mortality among older adult earthquake trauma patients (OAETPs) and created a screening model. METHODS: Data on 7,308 OAETPs from the West China Earthquake Patients Database were analyzed retrospectively. The 35 variables that can be obtained rapidly on arrival at the hospital were collected. Least absolute shrinkage and selection operator (LASSO) regression analysis was performed. Then, the nomogram for assessing the mortality of OAETPs was constructed. RESULTS: We identified 10 independent mortality-related factors that contributed to the inhospital mortality of OAETPs. The 10 factors included age (odds ratio [OR]=1.061, 95% confidence interval [CI]:1.031–1.090), dementia (OR=5.146, 95%CI: 1.169–17.856), coronary heart disease (CHD; OR=23.441, 95%CI: 4.799–83.927), malignant tumor (OR=8.497, 95%CI: 3.583–17.967), deep vein thrombosis (DVT; OR=7.110, 95%CI: 1.369–27.168), chronic kidney disease(CKD; OR=11.783, 95%CI: 5.419–24.407), pulse rate (PR; OR=1.036, 95%CI: 1.022–1.048), mean artery pressure (MAP; OR=0.960, 95%CI: 0.945–0.975), Glasgow Coma Scale (GCS; OR=0.864, 95%CI: 0.760–0.972), and Triage Revised Trauma Score (T-RTS, OR=0.485, 95%CI: 0.351–0.696). CONCLUSION: The 10 mortality-related factors could be quickly obtained on hospital arrival and should be the focal point of future earthquake response strategies regarding hospitalized older adults with trauma. A nomogram was constructed based on the factors for screening OAETPs with a higher risk of in-hospital mortality. [ABSTRACT FROM AUTHOR]

Chronic tendon ruptures are common disorders in orthopedics. The conventional surgical methods used to treat them often require the support of implants. Due to the non-availability of suitable materials, 3D-printed polycaprolactone (PCL) scaffolds were designed from two different starting materials as suitable candidates for tendon-implant applications. For the characterization, mechanical testing was performed. To increase their biocompatibility, the PCL-scaffolds were plasma-treated and coated with fibronectin and collagen I. Cytocompatibility testing was performed using L929 mouse fibroblasts and human-bone-marrow-derived mesenchymal stem cells. The mechanical testing showed that the design adaptions enhanced the mechanical stability. Cell attachment was increased in the plasma-treated specimens compared to the control specimens, although not significantly, in the viability tests. Coating with fibronectin significantly increased the cellular viability compared to the untreated controls. Collagen I treatment showed an increasing trend. The desired cell alignment and spread between the pores of the construct was most prominent on the collagen-I-coated specimens. In conclusion, 3D-printed scaffolds are possible candidates for the development of tendon implants. Enhanced cytocompatibility was achieved through surface modifications. Although adaptions in mechanical strength still require alterations in order to be applied to human-tendon ruptures, we are optimistic that a suitable implant can be designed. [ABSTRACT FROM AUTHOR]

Polycaprolactone (PCL) scaffold is a common biological material for tissue engineering, owing to its good biocompatibility, biodegradability and plasticity. However, it is not suitable for osteoblast adhesion and regeneration of bone tissue due to its non-biological activity, poor mechanical strength, slow degradation speed, smooth surface and strong hydrophobicity. To improve the mechanical properties and biocompatibility of PCL scaffold, the PCL/nHA scaffolds were prepared by melting and blending different proportions of nano-hydroxyapatite (nHA) with PCL by the near-field direct-writing melt electrospinning technology in this study. The morphology, porosity, mechanical properties and in vitro biocompatibility of the PCL/nHA scaffolds were studied. The results showed that when the proportion of nHA was less than or equal to 25%, PCL/nHA composite scaffolds were easily formed in which bone marrow mesenchymal stem cells proliferated successfully. When the proportion of nHA was 15%, the PCL/nHA composite scaffolds had excellent structural regularity, good fiber uniformity, outstanding mechanical stability and superior biocompatibility. The PCL/nHA composite scaffolds were ideal scaffold materials, which would broaden their applications for bone tissue engineering. [ABSTRACT FROM AUTHOR]