692 research outputs found

    In situ Polymerization of Multi-Walled Carbon Nanotube/Nylon-6 Nanocomposites and Their Electrospun Nanofibers

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    Multiwalled carbon nanotube/nylon-6 nanocomposites (MWNT/nylon-6) were prepared by in situ polymerization, whereby functionalized MWNTs (F-MWNTs) and pristine MWNTs (P-MWNTs) were used as reinforcing materials. The F-MWNTs were functionalized by Friedel-Crafts acylation, which introduced aromatic amine (COC6H4-NH2) groups onto the side wall. Scanning electron microscopy (SEM) images obtained from the fractured surfaces of the nanocomposites showed that the F-MWNTs in the nylon-6 matrix were well dispersed as compared to those of the P-MWNTs. Both nanocomposites could be electrospun into nanofibers in which the MWNTs were embedded and oriented along the nanofiber axis, as confirmed by transmission electron microscopy. The specific strength and modulus of the MWNTs-reinforced nanofibers increased as compared to those of the neat nylon-6 nanofibers. The crystal structure of the nylon-6 in the MWNT/nylon-6 nanofibers was mostly γ-phase, although that of the MWNT/nylon-6 films, which were prepared by hot-pressing the pellets between two aluminum plates and then quenching them in icy water, was mostly α-phase, indicating that the shear force during electrospinning might favor the γ-phase, similarly to the conventional fiber spinning

    REMOTE SENSING OF WAVE DIRECTIONALITY BY TWO-DIMENSIONAL DIRECTIONAL WAVELETS : PART 2. APPLICATIONS TO THE NUMERICAL AND FIELD DATA

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    This paper presents the results of a study investigating methods of interpretation of wave directionality based on wavelet transform. In part 1 of this paper, the tools to be used in detection of wave directionality, i. e., the Morlet and Cauchy wavelets, were described. This paper presents the application results of the directional wavelet to numerically generated images and video images taken in laboratory wave flume, river, and sea. The results showed that directional wavelet transform can be an efficient tool in detecting wave directionality with extremely low effort and cost when it is compared to traditional practices in use

    A STUDY ON THE TWO-ROW EFFECT IN THE SLOSHING PHENOMENON

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    In this study, changes in fluid impact loads inside a tank were examined according to a two-row tank arrangement in an LNG-FPSO (Liquefied Natural Gas-Floating Production Storage Offloading) vessel. The motion RAO (Response Amplitude Operator) of the LNG-FPSO, coupled with the sloshing phenomenon inside the tank, was calculated by using HydroStar by Bureau Veritas. The motion simulation in the tank was conducted under filling ratios of 30%H, 60%H, and 80%H. The RAO in each condition was calculated according to the one-row and the two-row tank arrangement. The motion response spectrum using the calculated RAO and the JONSWAP (Joint North Sea Wave Analysis Project) spectrum were computed by implementing irregular motion according to each filling ratio and tank arrangement. The sloshing phenomenon inside the tank was implemented by using a 6-DOF (Degree Of Freedom) sloshing motion platform; impact pressure on the walls of the tank was measured with pressure sensors installed inside the tank. The sloshing experiment was conducted under the three filling ratios in the one-row and the two-row tank arrangement and impact loads were compared under each filling ratio according to the one-row and the two-row tank arrangement

    Malignancies in Korean Patients with Inflammatory Myopathy

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    The aim of this study was to assess the prevalence and the common type of malignancies in Korean patients with polymyositis (PM) and dermatomyositis (DM) and to evaluate the differences of clinical and laboratory findings between patients with malignancy and those without malignancy. Forty-one Korean patients, who were diagnosed as PM or DM, were enrolled in this study. They fulfilled the Bohan and Peter's criteria for a definite diagnosis of PM and DM. Patients with PM were 25 and those with DM were 16. Eleven out of 41 patients (26.8%) had malignancies. The malignancy was diagnosed simultaneously or later in 81.8% of patients with inflammatory myopathy (IM). The breast cancer was the most common malignancy. In this study, forty three years old as a screening age for malignancy had 88.9% sensitivity and 50.2% specificity. The serum levels of creatine kinase (CK) were significantly lower in patients with malignancy than those without malignancy

    Design of Process Parameters in Electromagnetic Forming Apparatus by FEM

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    Electromagnetic forming (EMF) process is one of a high-speed forming process, which uses an electromagnetic body (Lorentz) force to deform work-piece. Advantages of EMF are summarized as improvement of formability, reduction in wrinkling, non-contact forming. In this study, the spiral coil is considered to evaluate formability in terms of pressure distribution of the forming process. It also is represented forming results of numerical analysis using ANSYS code. In the numerical simulation, RLC circuit coupled with spiral coil was made to consider the design parameters such as system input current and electromagnetic force. The simulation results show that even though input peak currents level are same level in each case, forming condition is certainly different because of frequency of input current and magnitude of current density and magnetic flux density. Finally, the simulation results appear that electromagnetic forming force apparently affected by input current frequency which determines magnitude of current density and magnetic flux density

    Advances in large PECVD processing technology up to Gen 11 for TFT LCD and OLED

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    Recent surging demands for larger (\u3e50”) TVs rapidly driving display processing technologies toward bigger substrate sizes up to 10m2 range. Meanwhile, high performance displays (OLED TV, iPad, iMac and 4K monitors…) have stretched a-Si mobility (85% LCD TVs in the world, supported recent starting of over a dozen largest TV factories worldwide Gen 8.5 and above, in particular enabled \u3e95% of advanced IGZO metal-oxide TFT display products including all latest OLED TVs, Apple iPads, iMac 5K or 4K displays, Microsoft Surface Pro 4, as well as major brand 4K or 8K monitors. Please click Additional Files below to see the full abstract

    High Glucose Accelerates Autophagy in Adult Rat Intervertebral Disc Cells

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    Study DesignIn vitro cell culture.PurposeThe purpose of this study was to investigate the effect of high glucose on autophagy in adult rat intervertebral disc cells.Overview of LiteratureDiabetes mellitus is considered to be an important etiologic factor for intervertebral disc degeneration, resulting in degenerative disc diseases. A glucose-mediated increase of autophagy is a major causative factor for the development of diseases associated with diabetes mellitus. However, no information is available for the effect of high glucose on autophagy in adult intervertebral disc cells.MethodsNucleus pulposus and annulus fibrosus cells were isolated from 24-week-old adult rats, cultured and placed in either 10% fetal bovine serum (normal control) or 10% fetal bovine serum plus two different high glucose concentrations (0.1 M and 0.2 M) (experimental conditions) for one and three days, respectively. The expressions of autophagy markers, such as beclin-1, light chain 3-I (LC3-I) and LC3-II, autophagy-related gene (Atg) 3, 5, 7 and 12, were identified and quantified.ResultsTwo high glucoses significantly increased the expressions of beclin-1, LC3-II, Atg3, 5, 7, and 12 in adult rat nucleus pulposus and annulus fibrosus cells in a dose- and time-dependent manner. The ratio of LC3-II/LC3-I expression was also increased in a dose-respectively time-dependent manner.ConclusionsThe results suggest that autophagy of adult nucleus pulposus and annulus fibrosus cells might be a potential mechanism for the intervertebral disc degeneration in adult patients with diabetes mellitus. Thus, the prevention of autophagy in adult intervertebral disc cells might be considered as a novel therapeutic target to prevent or to delay the intervertebral disc degeneration in adult patients with diabetes mellitus

    Adenosine washing improves the retention rate of fat grafts under conditions of obesity

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    Background Fat grafting is a commonly employed aesthetic procedure for contour enhancement. However, outcome prediction is challenging due to the complex regeneration and remodeling processes involved. We investigated whether adenosine improves engraftment and fat graft survival under conditions of obesity. Methods Fat was harvested from mice fed a high-fat diet. This fat was washed with either Krebs-Ringer bicarbonate HEPES buffer (the vehicle group) or a buffer containing 500 nM adenosine (the adenosine wash group). Subsequently, the fat was transplanted into normal mice at 0.2 mL per mouse. In both groups, 50% of the mice were sacrificed at 1 week and the remainder at 4 weeks post-transplantation. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis was conducted during week 1. In week 4, micro-computed tomography, immunofluorescence staining, and RT-qPCR were performed. A sample of the initially harvested fat was set aside for lipolysis assay. Results Adenosine washing improved fat graft retention volumes by up to 50%. One week post-transplantation, the expression of adipogenic and angiogenic genes was found to be upregulated in the adenosine wash group. After 4 weeks, immunofluorescence staining revealed greater adipocyte integrity and an increased number of vessels. Furthermore, adenosine appeared to modulate inflammation by stabilizing the lipolysis rate. Conclusions Adenosine washing increased the fat graft survival rate under conditions of obesity. Clinically, this suggests a simple, cost-effective adjuvant method for improving fat graft survival in individuals with obesity. Further research is warranted to elucidate the underlying mechanisms and explore the applicability of this technique for autologous transplantation

    Diverse clinical presentation of primary spontaneous pneumothorax in patients with pectus excavatum

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    ObjectivePatients with primary spontaneous pneumothorax (PSP) tend to be young, tall, and thin, as do those with pectus excavatum (PE). Notably, the Haller index, which measures the severity of PE, tends also to be higher in patients with PSP, further suggesting a potential predisposing factor for the development of PSP in individuals with PE. This study aimed to share clinical experiences with case series of concomitant PSP and PE and to emphasize the importance of evaluating these two conditions together.MethodsIn this single-center study, we conducted a retrospective records review to identify patients who were diagnosed and treated (including surgical or conservative treatment and follow-up observation) for the diagnosis of PE between July 2011 and February 2023. From these, we selected patients who were diagnosed with both PE and PSP and analyzed their clinical presentations.ResultsAmong a total of 139 patients with PE, there were 8 (5.76%) who had concurrent diagnoses of PE and PSP and who underwent surgery for PSP, PE, or both. The average age of these 8 patients (male:female = 7:1) was 19.38 years. The 8 patients were grouped into four categories based on their clinical scenarios. Group A had 1 patient with PE diagnosed first, followed by the discovery of PSP during evaluation; Group B included 2 patients initially presenting with PSP and subsequently diagnosed with PE during evaluation; Group C consisted of 1 patient who had PSP before undergoing surgical PE correction; and Group D comprised 4 patients who developed PSP after PE correction.ConclusionsThe incidence of PSP in patients with PE was 5.76% (8 out of 139 patients), indicating the importance of vigilant monitoring for PSP prior to PE surgery, and vice versa. Furthermore, the authors recommend close observation for PSP independent of PE surgery, even in the absence of postoperative complications
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