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The Irish Sea and the Baltic Sea are nowadays still the two most Cs-137 contaminated Seas worldwide. However, the origins of this contaminations are completely different. While the Baltic Sea was unintentionally contaminated due to global fallout after the accident in the Chernobyl nuclear powerplant in 1986, the Irish sea was intentionally used for low level liquid radioactive waste discharges from the Sellafield nuclear reprocessing facility (called Windscale until 1981) between the 1950s and 1990s. Nowadays, more than 30 years later, it is still possible to detect these contaminations in fish, water and sediments of both seas. Since fish are an important part of the human diet, monitoring Cs-137 levels in fish is essential for assessing the potential radiation exposure to humans. In 2019 and 2020 two surveys were dedicated to study the current levels of radioactive contamination in fish species from both Seas. During both surveys, fish samples were collected and analysed by gamma spectrometry later on. The results show that the average Cs-137 activity in benthic, demersal and pelagic fish species from the Baltic Sea are 2.7, 4.6 and 4.2, respectively, times higher than the corresponding values of the Irish Sea. Based on this and two other comparisons, it is concluded that the Baltic Sea is the most contaminated with Cs-137.
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BACKGROUND: In the last decade, notable progress in mechatronics paved the way for a new generation of arm prostheses, expanding motor capabilities thanks to their multiple active joints. Yet, the design of control schemes for these advanced devices still poses a challenge, especially with the limited availability of command signals for higher levels of arm impairment. When addressing this challenge, current commercial devices lack versatility and customizing options to be employed as test-beds for developing novel control schemes. As a consequence, researchers resort to using lab-specific experimental apparatuses on which to deploy their innovations, such as virtual reality setups or mock prosthetic devices worn by unimpaired participants. METHODS: To meet this need for a test-bed, we developed the Smart Arm platform, a human-like, multi-articulated robotic arm that can be worn as a trans-humeral arm prosthesis. The design process followed three principles: provide a reprogrammable embedded system allowing in-depth customization of control schemes, favor easy-to-buy parts rather than custom-made components, and guarantee compatibility with industrial standards in prosthetics. RESULTS: The Smart ArM platform includes motorized elbow and wrist joints while being compatible with commercial prosthetic hands. Its software and electronic architecture can be easily adapted to build devices with a wide variety of sensors and actuators. This platform was employed in several experiments studying arm prosthesis control and sensory feedback. We also report our participation in Cybathlon, where our pilot with forearm agenesia successfully drives the Smart Arm prosthesis to perform activities of daily living requiring both strength and dexterity. CONCLUSION: These application scenarios illustrate the versatility and adaptability of the proposed platform, for research purposes as well as outside the lab. The Smart Arm platform offers a test-bed for experimenting with prosthetic control laws and command signals, suitable for running tests in lifelike settings where impaired participants wear it as a prosthetic device. In this way, we aim at bridging a critical gap in the field of upper limb prosthetics: the need for realistic, ecological test conditions to assess the actual benefit of a technological innovation for the end-users.
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Miembros Artificiales , Diseño de Prótesis , Robótica , Humanos , Diseño de Prótesis/métodos , Robótica/instrumentación , Brazo/fisiologíaRESUMEN
Background: A retronychia classification system is overdue considering the most recent publications. Using the keyword "retronychia", publications with a narrative literature review were selected from PubMed/MEDLINE, EMBASE and Google Scholar, adding a few select papers. Summary: This article proposes a theoretical pathophysiological basis for retronychia. Several factors alter the clinical picture of retronychia: length and periodicity of backward displacement, duration of disease, intensity of paronychia, presence and type of nail stacking (polymeronychia), and remodeling of the nail apparatus (elevation of the proximal nail, nail bed shortening, retroversion of the distal nail fold and acquired malalignment). Key Messages: With these factors in mind, we propose a new classification system for retronychia: A standing for acute, O for ongoing, and C for chronic. We believe this easy system may increase the diagnostic acuity for the disease and its understanding.
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Insecticide resistance is widespread in global bed bug populations. Both common bed bugs and tropical bed bugs are pyrethroid-resistant among most field populations. Plant-based products and nonconventional pesticides offer minimal-risk strategies for managing bed bug resistance, but this strategy has yet to be formally evaluated in Cimex hemipterus (F.) (Hemiptera: Cimicidae). Here, several commercial plant-based formulations (Cedarcide, EcoRaider (also known as EcoVenger), EcoSMART, and Bio-D), a novel product, Provecta, and a pyrethroid insecticide, Pesguard FG161 were tested against pyrethroid-susceptible and resistant strains of C. hemipterus using direct spray, residual exposure, and egg dipping assays. Direct spray treatments outperform residual applications against all tested bed bug strains. Cedarcide exhibits the highest consistency in eliminating bed bugs, followed by EcoRaider, EcoSMART, and Provecta that outperform Bio-D and Pesguard FG161. In comparison to Pesguard FG161, all plant-based insecticide products and Provecta showed higher efficacy against pyrethroid-resistant strains. Although effective, product efficacy varies in terms of speed. Cedarcide kills all bed bugs within 1 min after spraying; however, other products can take up to 9 days to achieve 100% mortality. The efficacy of all products was reduced when evaluated on fabric surface (42%-65% mortality). Cedarcide and EcoRaider reduced egg hatchability by 37%-73% and 47%-70%, respectively. This study suggests that certain plant-based insecticides and an unconventional insecticide can serve as alternative direct spray treatments for managing tropical bed bugs, though their residual effects are limited.
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In light of the growing demand for novel biocatalysts and enzyme production methods, this study aimed to evaluate the potential of Aspergillus tubingensis for producing lipase under submerged culture investigating the influence of culture time and inducer treatment. Moreover, this study also investigated conditions for the immobilization of A. tubingensis lipase by physical adsorption on styrene-divinylbenzene beads (Diaion HP-20), for these conditions to be applied to an alternative immobilization system with a packed-bed reactor. Furthermore, A. tubingensis lipase and its immobilized derivative were characterized in terms of their optimal ranges of pH and temperature. A. tubingensis was shown to be a good producer of lipase, obviating the need for inducer addition. The enzyme extract had a hydrolytic activity of 23 U mL-1 and achieved better performance in the pH range of 7.5 to 9.0 and in the temperature range of 20 to 50 °C. The proposed immobilization system was effective, yielding an immobilized derivative with enhanced hydrolytic activity (35 U g-1), optimum activity over a broader pH range (5.6 to 8.4), and increased tolerance to high temperatures (40 to 60 â). This research represents a first step toward lipase production from A. tubingensis under a submerged culture and the development of an alternative immobilization system with a packed-bed reactor. The proposed system holds promise for saving time and resources in future industrial applications.
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This work applied BM as support for immobilization of lipase TLL in packed-bed reactor and its application for the synthesis of hexyl laurate. Initially, the percolation of a solution containing 5 mg of TLL at 25 oC generated an immobilized derivative with hydrolytic activity of 504.7 U/g and 31.7% of recovered activity. Subsequent treatment with n-hexane, as well as the effect of temperature on the immobilization process were able to improve the activities of the final BM-TLLF, achieving a hydrolysis activity of 7023 U/g and esterification activity of 430 U/g against 142 U/g and 113.5 U/g respectively presented by commercial TLIM. Desorption studies showed that the TL IM has 18 mg of protein per gram of support, compared to 4.92 mg presented by BM-TLL. Both biocatalysts were applied to synthesize hexyl laurate, achieving 98% conversion at 40°C within a residence time of 2 hours. Notably, BM-TLLF displayed exceptional recyclability, maintaining catalytic efficiency over 12 cycles. This reflects a productivity of 180 mg of product/h/U of the enzyme, surpassing 46 mg/h/U obtained for TLIM. These results demonstrate the efficacy of continuous flow technology in creating a competitive and integrated process offering an exciting alternative for the valorization of residual lignocellulosic biomass.
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In recent years, sleep problems among college students have become increasingly prominent, especially in the context of the COVID-19 pandemic, and their sleep quality has deteriorated dramatically, severely affecting their physical and mental health. Numerous research studies have investigated the relationship between mindfulness and sleep quality; however, it is still unclear what psychological process underlies this relationship. In the current study, college students' bed procrastination and self-control as mediating factors in the association between mindfulness and sleep quality were investigated. Using the convenience sampling method, 763 Chinese college students (mean age = 19.48 years, SD = 2.06) were recruited to complete self-reported questionnaires that included the Mindful Attention Awareness Scale, Self-Control Scale, Bed Procrastination Scale, and Sleep Quality Scale. All statistical analyses were performed using SPSS 23.0 software. Results showed that (a) mindfulness was positively associated with sleep quality; (b) both self-control and bed procrastination mediated the relationship between mindfulness and sleep quality, and (c) self-control and bed procrastination sequentially mediated the relationship between mindfulness and sleep quality. These findings collectively suggest a potential mechanism for how mindfulness influences sleep quality, providing a therapeutic target for mindfulness-based interventions aimed at helping college students improve sleep quality.
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COVID-19 , Atención Plena , Procrastinación , Autocontrol , Calidad del Sueño , Estudiantes , Humanos , COVID-19/psicología , COVID-19/epidemiología , Masculino , Femenino , Estudiantes/psicología , Adulto Joven , Autocontrol/psicología , Universidades , Adolescente , Encuestas y Cuestionarios , Pandemias , SARS-CoV-2 , Adulto , Autoinforme , Sueño/fisiología , China/epidemiologíaRESUMEN
Breast conserving treatment typically involves surgical excision of tumor and adjuvant radiotherapy targeting the breast area or tumor bed. Accurately defining the tumor bed is challenging and lead to irradiation of greater volume of healthy tissues. Preoperative stereotactic body radiotherapy (SBRT) which target tumor may solves that issues. We conducted a systematic literature review to evaluates the early toxicity and cosmetic outcomes of this promising treatment approach. Secondary we reviewed pathological complete response (pCR) rates, late toxicity, patient selection criteria and radiotherapy protocols. We retrieved literature from PubMed, Scopus, Web of Science, Cochrane, ScienceDirect, and ClinicalTrials.gov. The study adhered to the PRISMA 2020 guidelines. Ten prospective clinical trials (7 phase II, 3 phase I), encompassing 188 patients (aged 18-75 years, cT1-T3 cN0-N3 cM0, primarily with ER/PgR-positive, HER2-negative status,), were analyzed. Median follow-up was 15 months (range 3-30). Treatment involved single-fraction SBRT (15-21Gy) in five studies and fractionated (19.5-31.5Gy in 3 fractions) in the rest. Time interval from SBRT to surgery was 9.5 weeks (range 1-28). Acute and late G2 toxicity occurred in 0-17% and 0-19% of patients, respectively, G3 toxicity was rarely observed. The cosmetic outcome was excellent in 85-100%, fair in 0-10% and poor in only 1 patient. pCR varied, showing higher rates (up to 42%) with longer intervals between SBRT and surgery and when combined with neoadjuvant systemic therapy (up to 90%). Preoperative SBRT significantly reduce overall treatment time, enabling to minimalize volumes. Early results indicate excellent cosmetic effects and low toxicity.
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Neoplasias de la Mama , Radiocirugia , Humanos , Radiocirugia/métodos , Radiocirugia/efectos adversos , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Neoplasias de la Mama/patología , Femenino , Cuidados PreoperatoriosRESUMEN
This study presents a bidirectional flow tidal bioreactor designed to enhance H2-driven CO2 biomethanation. The bioreactor alternated biofilms between immersion in nutrient solution and exposure to H2/CO2, creating alternating dry and wet states. This tidal operation minimized liquid film thickness during dry periods and ensured uniform nutrient distribution during wet periods. Bidirectional H2/CO2 supply was used to reduce biofilm thickness heterogeneity across the reactor height. CO2 biomethanation remained stable with an empty bed residence time of 9.7 min, achieving a methane (CH4) formation rate of 26.8 Nm3 CH4/(m3·d). The product gas contained 95.0 ± 2.5 % CH4, with a H2/CO2 conversion efficiency of 90.8 %. Tidal operation mitigated the buildup of dissolved and suspended organics, such as organic acids and detached biofilms. Dominant bacteria in biofilms included fermentative species like Petrimonas and H2-utilizing homoacetogens like Sporomusa. Enriched hydrogenotrophic methanogens, particularly Methanobacterium, were observed. Overall, this study highlights the bioreactor's effectiveness in improving CO2 biomethanation.
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INTRODUCTION: Traditionally, wards in acute care hospitals consist predominately of multioccupancy bays with some single rooms. There is an increasing global trend towards a higher proportion of single rooms in hospitals, with the UK National Health Service (NHS) advocating for single-room provision in all new hospital builds. There is limited evidence on the impact of a ward environment incorporating mostly single and some multioccupancy bays on patient care and organisational outcomes. METHODS AND ANALYSES: This study will assess the impact of a newly designed 28-bedded ward environment, with 20 single rooms and two four-bedded bays, on patient and staff experiences and outcomes in an acute NHS Trust in East England. The study is divided into two work packages (WP)-WP1 is a quantitative data extraction of routinely collected patient and staff data while WP2 is a mixed-methods process evaluation consisting of one-to-one, in-depth, semistructured interviews with staff, qualitative observations of work processes on the ward and a quantitative data evaluation of routinely collected process evaluation data from patients and staff. ETHICS AND DISSEMINATION: Ethical approval was obtained from the UK Health Research Authority (IRAS ID: 334395). Study findings will be shared with key stakeholders, published in peer-reviewed high-impact journals and presented at relevant conferences.
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Habitaciones de Pacientes , Medicina Estatal , Humanos , Inglaterra , Ocupación de Camas , Arquitectura y Construcción de Hospitales , Reino Unido , Proyectos de Investigación , Satisfacción del PacienteRESUMEN
OBJECTIVES: The value of thrombectomy in patients with acute ischemic stroke cannot be understated. As such, whether these patients get access to this treatment can significantly impact their disease outcomes. We analyzed the trends in thrombectomy adoption between teaching and non-teaching hospitals in the United States, and their impact on overall patient care. MATERIALS AND METHODS: We conducted a retrospective analysis of hospital admissions in the Nationwide Inpatient Sample with a diagnosis of acute ischemic stroke between 2012 and 2020. We compared the annual total number and proportion of patients undergoing thrombectomy between teaching and non-teaching hospitals, and their corresponding outcomes. RESULTS: 3,823,490 and 1,875,705 patients were admitted to teaching and non-teaching hospitals during the study duration, respectively. The proportion of patients who underwent thrombectomy increased from 1.60% to 7.02% (p-value for trend p<0.001) in teaching hospitals and from 0.32% to 2.20% (p-value trend p<0.001) in non-teaching hospitals. The absolute increase in the number of acute ischemic stroke patients undergoing thrombectomy was highest in teaching hospitals particularly those with large bed size, an increase from 3635 patients in 2012 to 24,730 patients in 2020. Higher rates of intravenous thrombolysis and patient transfer prior to thrombectomy were seen in teaching hospitals compared with non-teaching hospitals. CONCLUSIONS: The study highlights disparities between teaching and non-teaching hospitals, with teaching hospitals showing a disproportionately higher rate of thrombectomy adoption in acute ischemic stroke patients. Further studies are needed to understand the barriers to the adoption of thrombectomy in non-teaching hospitals.
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Water contaminated with arsenic presents serious health risks, necessitating effective and sustainable removal methods. This article proposes a method for removing arsenic from water by impregnating biochar with iron oxide (Fe2O3) from brown seaweed (Sargassum polycystum). After the seaweed biomass was pyrolyzed at 400 °C, iron oxide was added to the biochar to increase its adsorptive sites and surface functional groups, which allowed the binding of arsenic ions. Batch studies were conducted to maximize the effects of variables, including pH, contact time, arsenic concentration, and adsorbent dosage, on arsenic adsorption. The maximum arsenic adsorption efficiency of 96.7% was achieved under optimal conditions: pH 6, the adsorbent dosage of 100 mg, the initial arsenic concentration of 0.25 mg/L, and a contact time of 90 min. Langmuir and Freundlich's isotherms favored the adsorption process, while the kinetics adhered to a pseudo-second-order model, indicating chemisorption as the controlling step. Column studies revealed complete saturation after 200 min, and the adsorption behavior fits both the Adams-Bohart and Thomas models, demonstrating the potential for large-scale application. The primary mechanism underlying the interaction between iron-modified biochar and arsenic ions is surface complexation, enhanced by increased surface area and porosity. This study highlights the significant contribution of iron-modified biochar derived from macroalgae as an effective and sustainable solution for arsenic removal from water.
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Arsénico , Carbón Orgánico , Compuestos Férricos , Algas Marinas , Contaminantes Químicos del Agua , Purificación del Agua , Arsénico/química , Arsénico/aislamiento & purificación , Carbón Orgánico/química , Algas Marinas/química , Adsorción , Compuestos Férricos/química , Purificación del Agua/métodos , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Cinética , Concentración de Iones de HidrógenoRESUMEN
The transition from wakefulness to sleep occurs when the core body temperature decreases. The latter is facilitated by an increase in the cutaneous blood flow, which dissipates internal heat into the micro-environment surrounding the sleeper's body. The rise in cutaneous blood flow near sleep onset causes the distal (hands and feet) and proximal (abdomen) temperatures to increase by about 1 °C and 0.5 °C, respectively. Characterizing the dynamics of skin temperature changes throughout sleep phases and understanding its relationship with sleep quality requires a means to unobtrusively and longitudinally estimate the skin temperature. Leveraging the data from a temperature sensor strip (TSS) with five individual temperature sensors embedded near the surface of a smart bed's mattress, we have developed an algorithm to estimate the distal skin temperature with a minute-long temporal resolution. The data from 18 participants who recorded TSS and ground-truth temperature data from sleep during 14 nights at home and 2 nights in a lab were used to develop an algorithm that uses a two-stage regression model (gradient boosted tree followed by a random forest) to estimate the distal skin temperature. A five-fold cross-validation procedure was applied to train and validate the model such that the data from a participant could only be either in the training or validation set but not in both. The algorithm verification was performed with the in-lab data. The algorithm presented in this research can estimate the distal skin temperature at a minute-level resolution, with accuracy characterized by the mean limits of agreement [-0.79 to +0.79 °C] and mean coefficient of determination R2=0.87. This method may enable the unobtrusive, longitudinal and ecologically valid collection of distal skin temperature values during sleep. Therelatively small sample size motivates the need for further validation efforts.
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Algoritmos , Lechos , Temperatura Cutánea , Sueño , Temperatura Cutánea/fisiología , Humanos , Sueño/fisiología , Masculino , Femenino , Adulto , Vigilia/fisiología , Monitoreo Fisiológico/métodos , Monitoreo Fisiológico/instrumentaciónRESUMEN
The Inconel 718 superalloy demonstrates the potential to fabricate high-temperature components using additive manufacturing. However, additively manufactured Inconel 718 typically exhibits low strength, necessitating post-heat treatments for precipitate strengthening. This study investigated the microstructures and mechanical properties of the Inconel 718 superalloy fabricated via laser powder bed fusion. The room-temperature and high-temperature tensile properties of the Inconel 718 alloy samples following various post-heat treatments were evaluated. The results indicate that the as-built samples exhibited columnar grains with fine cell structures. Solution treatment resulted in δ phase formation and grain recrystallization. Subsequent double aging led to finely distributed nanoscale γ' and γⳠparticles. These nanoscale particles provided high strength at both room and high temperatures, resulting in a balanced strength and ductility comparable to the wrought counterpart. High-temperature nanoindentation analyses revealed that the double-aging samples exhibited very high hardness and low creep rates at 650 °C.
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The ash generated by Circulating Fluidized Bed (CFB) boilers is featured by its looseness and porosity, low content of glassy substances, and high contents of calcium (Ca) and sulfur (S), thus resulting in a low comprehensive utilization rate. Currently, the predominant treatment approach for CFB ash and slag is stacking, which may give rise to issues like environmental pollution. In this paper, CFB ash (with a CaO content of 7.64% and an SO3 content of 1.77%) was used as the main raw material. The high-temperature melting characteristics, viscosity-temperature characteristics, and initial crystallization temperature of samples with different acidity coefficients were investigated. The final drawing temperature range of the samples was determined, and mechanical property tests were conducted on the prepared inorganic fibers. The results show that the addition of dolomite powder has a significant reducing effect on the complete liquid phase temperature. The final drawing temperatures of the samples with different acidity coefficients range as follows: 1270-1318 °C; 1272-1351 °C; 1250-1372 °C; 1280-1380 °C; 1300-1382 °C; and 1310-1384 °C. The drawing temperature of this system is slightly lower than that of basalt fibers. Based on the test results of the mechanical properties of inorganic fibers, the Young's modulus of the inorganic fibers prepared through the experiment lies between 55 GPa and 74 GPa, which basically meets the performance requirements of inorganic fibers. Consequently, the method of preparing inorganic fibers by using CFB ash and dolomite powder is entirely feasible.
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OBJECTIVE: This work explores concurrent optical and magnetic stimulation (COMS) effects on hard-to-heal wounds in real-world settings. METHOD: In this case series, participants received COMS 1-3 times per week for up to 12 weeks alongside standard wound care. RESULTS: A total of 27 patients (18 female and nine male) were included. Mean age was 72 years. Participants' wounds that were unresponsive to standard wound care included: venous leg ulcers (VLUs, n=13); mixed leg ulcers (MLUs, n=4); diabetic foot ulcers (DFUs, n=1); pressure ulcers (PUs, n=5); and traumatic wounds (TWs, n=4). On average, COMS was applied twice a week, resulting in an overall mean wound area reduction of 69%. In 24 participants, COMS was used primarily to achieve wound closure by the end of the 12-week period, of which: 12 were classified as complete wound closure (50%; VLUs=8, PUs=3 and TW=1); four as likely-to-heal (17%; VLUs=2 and MLUs=2); four as 'improved' (17%; MLU=1, DFU=1 and TWs=2); and four as 'non-responding' (17%; VLUs=3 and MLU=1). The best results were achieved in PUs and VLUs (respectively 100% and 62% categorised as completely healed). When used in participants where its purpose was other than that of achieving wound closure, COMS was successfully used to debride two PUs, and for wound bed preparation in one TW. CONCLUSION: In this case series, COMS showed positive effects and appeared to be beneficial in healing different types of hard-to-heal wounds in community health and homecare settings. Novel COMS therapy aspects emerged: (1) positive outcomes for PU and VLU treatment; (2) COMS as a potential debridement tool when sharp debridement is unfeasible; and (3) COMS as a promising method to prepare wound beds for subsequent skin grafting or skin replacement procedures.
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Cicatrización de Heridas , Humanos , Femenino , Masculino , Anciano , Anciano de 80 o más Años , Persona de Mediana Edad , Magnetoterapia/métodos , Úlcera de la Pierna/terapia , Resultado del Tratamiento , Úlcera por Presión/terapia , Úlcera Varicosa/terapia , Pie Diabético/terapiaRESUMEN
Zinc (Zn)-based biodegradable metals (BMs) fabricated through conventional manufacturing methods exhibit adequate mechanical strength, moderate degradation behavior, acceptable biocompatibility, and bioactive functions. Consequently, they are recognized as a new generation of bioactive metals and show promise in several applications. However, conventional manufacturing processes face formidable limitations for the fabrication of customized implants, such as porous scaffolds for tissue engineering, which are future direction towards precise medicine. As a metal additive manufacturing technology, laser powder bed fusion (L-PBF) has the advantages of design freedom and formation precision by using fine powder particles to reliably fabricate metallic implants with customized structures according to patient-specific needs. The combination of Zn-based BMs and L-PBF has become a prominent research focus in the fields of biomaterials as well as biofabrication. Substantial progresses have been made in this interdisciplinary field recently. This work reviewed the current research status of Zn-based BMs manufactured by L-PBF, covering critical issues including powder particles, structure design, processing optimization, chemical compositions, surface modification, microstructure, mechanical properties, degradation behaviors, biocompatibility, and bioactive functions, and meanwhile clarified the influence mechanism of powder particle composition, structure design, and surface modification on the biodegradable performance of L-PBF Zn-based BM implants. Eventually, it was closed with the future perspectives of L-PBF of Zn-based BMs, putting forward based on state-of-the-art development and practical clinical needs.
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Gasification is a thermochemical process that has gained significant interest in the field of biomass energy conversion. Despite the level of technological maturity of the process, the dynamic variation of the process as a result of changes in both the properties of the gasifying agent and biomass has not been analysed in sufficient depth. Therefore, the present study characterizes the process dynamically as a function of step-type changes in rice husk biomass moisture content and gasifying airflow. To identify stability conditions and the range for inducing disturbances, steady-state tests were carried out using a 32-factorial design. The experimental results demonstrate that within the tested range of airflow, the gasification process operates in the oxygen-limited zone. Despite increasing the airflow from 20 to 40 standard liters per minute (SLPM) and driving the reaction towards the combustion zone, the high temperatures achieved resulted in the gas reaching a peak Lower Heating Value (LHV) of 2.6 MJ/Nm3 and a gas power of 2.6 kW, with a Cold Gas Efficiency (CGE) of 62%. In contrast, the effect of biomass moisture content was negligible due to the thermal inertia of the reactor and the natural variation of the process. Dynamic evaluation revealed that the oxidation temperature and gas concentration were the variables that took the longest to return to stability after air disturbances. It took approximately 1200 s for the hydrogen (H2) concentration to stabilize, while the gas power required about 300 s. No clear results were observed regarding the impact of the dynamic disturbance in moisture content, which varied between 12.3% w.t and 21.5% w.t.
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The human heart is very adaptable, with chamber size, wall thickness and ventricular stiffness all modified by periods of inactivity or exercise training. Herein, we summarize the cardiac adaptations induced by changes in physical activity, ranging from bed rest and spaceflight to endurance exercise training, while also highlighting how the ageing process (a long-term model of inactivity) affects cardiac plasticity. Severe inactivity during bed rest or spaceflight leads to cardiac atrophy and ventriculo-vascular stiffening. Conversely, endurance training induces eccentric hypertrophy and enhances ventricular compliance, and can be used as an effective countermeasure to prevent adverse cardiac changes during prolonged periods of bed rest or spaceflight. With sedentary ageing, the heart undergoes concentric remodelling and irreversibly stiffens at advanced age. Specifically, older adults who initiate endurance training later in life are unable to improve ventricular compliance and diastolic function, suggesting reduced cardiac plasticity with advanced age; however, lifelong exercise training prevents age-associated cardiac remodelling and maintains cardiac compliance of older adults at a level similar to those of younger healthy individuals. Nevertheless, there are still many knowledge gaps related to cardiac remodelling and changes in cardiac function induced by bed rest, exercise training and spaceflight, as well as how these different stimuli may interact with advancing age. Future studies should focus on understanding what factors (sex, age, heritability, etc.) may influence the heart's responsiveness to training or deconditioning, as well as understanding the long-term cardiac consequences of spaceflight beyond low-Earth orbit with the added stimulus of galactic cosmic radiation.
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A novel technique for producing highly uniform structures from silica microspheres has been developed and tested. It is based on exploiting the temperature- and pressure-dependent solvent properties of sub/supercritical water toward silicon dioxide. The initial concept aimed to create a "hybrid" capillary chromatographic column on the border between a packed and a monolithic column that would combine the benefits of both. The resultant method that integrates dissolution and coalescence in a continuous process enabled the production of a range of permeable columns with high efficiency and varying sizes. Their internal structures were examined using scanning electron microscopy and characterized using microHPLC chromatography. The structures produced using this method may have diverse applications beyond the scope of analytical chemistry. They prove useful in scenarios where high pressure is necessary because of the high hydraulic resistance of small particles and/or the passing medium with a high flow rate. A simple test of a bridged-microsphere monolithic column and a discrete microsphere-packed column, both after chemical modification to the C18 stationary phase, indicated superior performance of the new type of monolithic columns.