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The advantage of 3D printing-that is, additive manufacturing (AM) of structural materials-has been severely compromised by their disappointing fatigue properties1,2. Commonly, poor fatigue properties appear to result from the presence of microvoids induced by current printing process procedures3,4. Accordingly, the question that we pose is whether the elimination of such microvoids can provide a feasible solution for marked enhancement of the fatigue resistance of void-free AM (Net-AM) alloys. Here we successfully rebuild an approximate void-free AM microstructure in Ti-6Al-4V titanium alloy by development of a Net-AM processing technique through an understanding of the asynchronism of phase transformation and grain growth. We identify the fatigue resistance of such AM microstructures and show that they lead to a high fatigue limit of around 1 GPa, exceeding the fatigue resistance of all AM and forged titanium alloys as well as that of other metallic materials. We confirm the high fatigue resistance of Net-AM microstructures and the potential advantages of AM processing in the production of structural components with maximum fatigue strength, which is beneficial for further application of AM technologies in engineering fields.
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OBJECTIVE: To analyze the causes of skin necrosis after penis lengthening surgery and corresponding treatment measures, and observe the clinical effect of free skin graft repair in the treatment of penile skin defects. METHODS: We retrospectively analyzed the clinical data on 12 cases of extensive penile skin necrosis and defect after penis lengthening surgery performed in our department from January 2017 to January 2022. The patients underwent free skin graft repair with medium- or full-thickness skin grafts from the thigh after wound preparation. RESULTS: The skin grafts survived well in all the 12 patients and the incisions healed in the first stage without any complications. At 6 months after surgery, skin sensation was mostly recovered in the area of penis skin grafting, no obvious skin ulceration or edema was observed, and the appearance of the penis was satisfactory. The IIEF-5 scores, Erectile Hardness Scale (EHS) scores, and the results of penile hardness tests of the patients all indicated normal erectile function. CONCLUSION: Free skin graft repair with autologous medium- or full-thickness skin grafts is a safe and effective surgical option for extensive penile skin necrosis after penis lengthening surgery.
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Pene , Piel , Humanos , Masculino , Necrosis , Pelvis , Pene/cirugía , Estudios RetrospectivosRESUMEN
BACKGROUND: The purpose of the current study was to assess the efficacy of tranexamic acid (TXA) on reducing bleeding in cardiac surgical patients with preoperative antiplatelet therapy (APT). METHODS: Five electronic databases were searched systematically for randomized-controlled trials (RCTs) assessing the impact of intravenous TXA on post-operative bleeding on cardiac surgical patients with preoperative APT until May 2024. Primary outcome of interest was post-operative blood loss. Secondary outcomes of interest included the incidence of reoperation due to post-operative bleeding, post-operative transfusion requirements of red blood cells (RBC), fresh-frozen plasma (FFP), and platelet concentrates. Mean difference (MD) with 95% confidence interval (CI) or odds ratios (OR) with 95% CI was employed to analyze the data. Subgroup and meta-regression analyses were performed to assess the possible influence of TXA administration on reducing bleeding and transfusion requirements. RESULTS: A total of 12 RCTs with 3018 adult cardiac surgical patients (TXA group, 1510 patients; Control group, 1508 patients) were included. The current study demonstrated that TXA significantly reduced post-operative blood loss (MD = - 0.38 L, 95% CI: - 0.73 to - 0.03, P = 0.03; MD = - 0.26 L, 95% CI: - 0.28 to - 0.24, P < 0.00001; MD = - 0.37 L, 95% CI: - 0.63 to - 0.10, P = 0.007) in patients receiving dual antiplatelet therapy (DAPT), aspirin, or clopidogrel, respectively. Patients in TXA group had significantly lower incidence of reoperation for bleeding as compared to those in Control group. The post-operative transfusion of RBC and FFP requirements was significantly lower in TXA group than Control group. Subgroup analyses showed that studies with DAPT discontinued on the day of surgery significantly increased the risk of post-operative blood loss [(MD: - 1.23 L; 95% CI: - 1.42 to - 1.04) vs. (MD: - 0.16 L; 95% CI: - 0.27 to - 0.05); P < 0.00001 for subgroup difference] and RBC transfusion [(MD: - 3.90 units; 95% CI: - 4.75 to - 3.05) vs. (MD: - 1.03 units; 95% CI: - 1.96 to - 0.10); P < 0.00001 for subgroup difference] than those with DAPT discontinued less than 5-7 days preoperatively. CONCLUSIONS: This meta-analysis demonstrated that TXA significantly reduced post-operative blood loss and transfusion requirements for cardiac surgical patients with preoperative APT. These potential clinical benefits may be greater in patients with aspirin and clopidogrel continued closer to the day of surgery. TRIAL REGISTRATION NUMBER: CRD42022309427.
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Energy, as an indispensable part of human life, has been a hot topic of research among scholars. The water kinetic energy generated by ocean currents, as a kind of clean energy, has high utilization rate, high power generation potential, and a broad prospect of powering microelectronic devices. As a result, the water kinetic piezoelectric energy harvester (WKPEH) has made significant progress in powering ocean sensors by harvesting ocean currents. This paper provides a comprehensive review of technologies that have been used in recent years to harvest energy from marine fluids using WKPEH. Detailed study of the energy harvesting mechanism of WKPEH. WKPEH can use the flutter-induced vibrations, vortex-induced vibrations, and wake oscillation principles to harvest water kinetic energy. The structural characteristics and output performance of each mechanism are also discussed and compared, and finally, a prospect on WKPEH is given.
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BACKGROUND: Magnetic resonance imaging (MRI) brain abnormalities have been reported in the corpus callosum (CC) of patients with adult-onset hypothyroidism. However, no study has directly compared CC-specific morphological or functional alterations among subclinical hypothyroidism (SCH), overt hypothyroidism (OH), and healthy controls (HC). Moreover, the association of CC alterations with cognition and emotion is not well understood. METHODS: Demographic data, clinical variables, neuropsychological scores, and MRI data of 152 participants (60 SCH, 37 OH, and 55 HC) were collected. This study investigated the clinical performance, morphological and functional changes of CC subregions across three groups. Moreover, a correlation analysis was performed to explore potential relationships between these factors. RESULTS: Compared to HC, SCH and OH groups exhibited lower cognitive scores and higher depressive/anxious scores. Notably, rostrum and rostral body volume of CC was larger in the SCH group. Functional connectivity between rostral body, anterior midbody and the right precentral and dorsolateral superior frontal gyrus were increased in the SCH group. In contrast, the SCH and OH groups exhibited a decline in functional connectivity between splenium and the right angular gyrus. Within the SCH group, rostrum volume demonstrated a negative correlation with Montreal Cognitive Assessment and visuospatial/executive scores, while displaying a positive correlation with 24-item Hamilton Depression Rating Scale scores. In the OH group, rostral body volume exhibited a negative correlation with serum thyroid stimulating hormone levels, while a positive correlation with serum total thyroxine and free thyroxine levels. CONCLUSIONS: This study suggests that patients with different stages of adult-onset hypothyroidism may exhibit different patterns of CC abnormalities. These findings offer new insights into the neuropathophysiological mechanisms in hypothyroidism.
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Cuerpo Calloso , Hipotiroidismo , Imagen por Resonancia Magnética , Humanos , Masculino , Cuerpo Calloso/diagnóstico por imagen , Cuerpo Calloso/fisiopatología , Cuerpo Calloso/patología , Femenino , Hipotiroidismo/fisiopatología , Hipotiroidismo/complicaciones , Adulto , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Pruebas Neuropsicológicas , Cognición/fisiologíaRESUMEN
Transurethral resection of ejaculatory duct (TURED) is a primary surgical approach to treat ejaculatory duct obstruction (EDO) caused by the ejaculatory duct cyst. Intraoperative excision of the verumontanum is usually required to expose the ejaculatory ducts. However, preserving the verumontanum structure allows for a better simulation of normal physiological anatomy. Maintaining the verumontanum may increase the risk of postoperative distal ejaculatory duct scarring, leading to recurrent obstruction or reduced semen volume. Therefore, we attempted a novel technique that preserves the verumontanum, which is relatively easier and safer compared to TURED. The following were the procedural steps: 1. A 6F seminal vesiculoscope was introduced through the external urethral orifice to the vicinity of the verumontanum, locating the opening of the affected-side ejaculatory duct and introducing a guidewire into the cyst. This successful step preserved the verumontanum, maximizing the retention of the anti-reflux mechanism in the distal ejaculatory duct. 2. The holmium laser enlarged the affected-side ejaculatory duct opening to 5 mm, decreasing the likelihood of postoperative closure of the ejaculatory duct opening and simplifying the procedure. 3. A window was created within the cyst to access the contralateral seminal vesicle, and then a holmium laser was used to burn and dilate the opening to 5 mm, redirecting the contralateral ejaculatory duct into the cystic cavity. This modification preserved the opening of the healthy-side ejaculatory duct and provided a new outflow passage for semen, reducing the risk of decreased semen volume postoperatively. The patients experienced no complications postoperatively, had shorter hospital stays, and showed improvement in semen volume. Hence, this surgical approach is simple yet effective.