994 research outputs found

    Attenuation of Cross-Flow Fan Noise Using Porous Stabilizers

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    This paper presents a qualitative analysis of controlling the cross-flow fan noise by using porous stabilizers. The stabilizer was originally a folded plate. It is changed into a porous structure which has a plenum chamber and vent holes on the front wall. In order to investigate the influences of using the porous stabilizers, experiments are carried out to measure the cross-flow fan aerodynamic performances and sound radiation. Meanwhile, the internal flow field of the fan is numerically simulated. The results show that the porous stabilizers have not produced considerable effect on the cross-flow fan's performance curve, but the noise radiated from the fan is strongly affected. This indicates the feasibility of controlling the cross-flow fan noise by using the porous stabilizers with selected porosity

    Screening for fear of cancer recurrence : instrument validation and current status in early stage lung cancer patients

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    Background Fear of cancer recurrence (FCR) is one of the most distressing concerns for cancer patients. A psychometrically validated brief scale is urgently needed for use in busy clinical oncology settings. This study aimed to (1) develop and validate the 7-item fear of cancer recurrence scale Chinese version (FCR7-C), and (2) explore the severity of FCR in post-operative early-stage lung cancer patients in Taiwan. Methods Early-stage lung cancer patients were recruited from a medical center in Taiwan. The FCR7-C was evaluated for content and construct validity and internal consistency reliability. Construct validity of FCR7-C was determined by the empirically supported correlation and confirmatory factor analysis (CFA). Results A total of 160 subjects were recruited. The FCR7-C was shown to have satisfactory content validity and internal consistency reliability (Cronbach's α = 0.9). The uni-dimensional structure was confirmed by CFA that showed a good fit for the model. The FCR7-C score correlates positively with the degree of most of the physical symptoms, anxiety, and depression, but correlates negatively with patient age, performance status, and quality of life. We found that 81.9% of patients reported at least some FCR, with a mean FCR severity of 15.18 (SD = 7.78). Conclusion FCR7-C is a brief screening tool with good psychometrics. Patients with early-stage lung cancer still revealed mild to moderate level of FCR. Applying the FCR7-C for to screen cancer patients’ distress and further develop personalized psychological interventions would be strongly suggested.Publisher PDFPeer reviewe

    Low Latency Edge Classification GNN for Particle Trajectory Tracking on FPGAs

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    In-time particle trajectory reconstruction in the Large Hadron Collider is challenging due to the high collision rate and numerous particle hits. Using GNN (Graph Neural Network) on FPGA has enabled superior accuracy with flexible trajectory classification. However, existing GNN architectures have inefficient resource usage and insufficient parallelism for edge classification. This paper introduces a resource-efficient GNN architecture on FPGAs for low latency particle tracking. The modular architecture facilitates design scalability to support large graphs. Leveraging the geometric properties of hit detectors further reduces graph complexity and resource usage. Our results on Xilinx UltraScale+ VU9P demonstrate 1625x and 1574x performance improvement over CPU and GPU respectively

    Direct Measurement of the Magnitude of van der Waals interaction of Single and Multilayer Graphene

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    Vertical stacking of monolayers via van der Waals assembly is an emerging field that opens promising routes toward engineering physical properties of two-dimensional (2D) materials. Industrial exploitation of these engineering heterostructures as robust functional materials still requires bounding their measured properties so to enhance theoretical tractability and assist in experimental designs. Specifically, the short-range attractive van der Waals forces are responsible for the adhesion of chemically inert components and are recognized to play a dominant role in the functionality of these structures. Here we reliably quantify the the strength of van der Waals forces in terms of an effective Hamaker parameter for CVD-grown graphene and show how it scales by a factor of two or three from single to multiple layers on standard supporting surfaces such as copper or silicon oxide. Furthermore, direct measurements on freestanding graphene provide the means to discern the interplay between the van der Waals potential of graphene and its supporting substrate. Our results demonstrated that the underlying substrates could enhance or reduce the van der Waals force of graphene surfaces, and its consequences are explained in terms of a Lifshitz theory-based analytical model

    Preliminary Findings of the High Quantity of Microplastics in Faeces of Hong Kong Residents

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    Microplastics are recognised as a ubiquitous and hazardous pollutant worldwide. These small-sized particles have been detected in human faeces collected from a number of cities, providing evidence of human ingestion of microplastics and their presence in the gastrointestinal tract. Here, using Raman spectroscopy, we identified an average of 50 particles g−1 (20.4–138.9 particles g−1 wet weight) in faeces collected from a healthy cohort in Hong Kong. This quantity was about five times higher than the values reported in other places in Asia and Europe. Polystyrene was the most abundant polymer type found in the faeces, followed by polypropylene and polyethylene. These particles were primarily fragments, but about two-thirds of the detected polyethylene terephthalate were fibres. More than 88% of the microplastics were smaller than 300 µm in size. Our study provides the first data on the faecal level, and thus the extent of ingestion, of microplastics in Hong Kong’s population. This timely assessment is crucial and supports the recently estimated ingestion rate of microplastics by Hong Kong residents through seafood consumption, which is one of the highest worldwide. These findings may be applicable to other coastal populations in South China with similar eating habits

    Structure-function analysis of CYP719As involved in methylenedioxy bridge-formation in the biosynthesis of benzylisoquinoline alkaloids and its de novo production

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    Benzylisoquinoline alkaloids (BIAs) are a type of secondary metabolite with clinical application value. (S)-stylopine is a special BIA which contains methylenedioxy bridge structures. CYP719As could catalyze the methylenedioxy bridge-formation on the A or D rings of protoberberine alkaloids, while displaying significant substrate regiospecificity. To explore the substrate preference of CYP719As, we cloned and identified five CyCYP719A candidates from Corydalis yanhusuo. Two CyCYP719As (CyCYP719A39 and CyCYP719A42) with high catalytic efficiency for the methylenedioxy bridge-formation on the D or A rings were characterized, respectively. The residues (Leu 294 for CyCYP719A42 and Asp 289 for CyCYP719A39) were identified as the key to controlling the regioselectivity of CYP719As affecting the methylenedioxy bridge-formation on the A or D rings by homology modeling and mutation analysis. Furthermore, for de novo production of BIAs, CyCYP719A39, CyCYP719A42, and their mutants were introduced into the (S)-scoulerine-producing yeast to produce 32\ua0mg/L (S)-stylopine. These results lay a foundation for understanding the structure-function relationship of CYP719A-mediated methylenedioxy bridge-formation and provide yeast strains for the BIAs production by\ua0synthetic biology

    Qiliqiangxin Rescues Mouse Cardiac Function by Regulating AGTR1/TRPV1-Mediated Autophagy in STZ-Induced Diabetes Mellitus

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    Background/Aims: To explore the potential role of qiliqiangxin (QLQX) A traditional Chinese medicine and the involvement of angiotensin II receptor type 1 (AGTR1) and transient receptor potential vanilloid 1 (TRPV1) in diabetic mouse cardiac function. Methods: Intragastric QLQX was administered for 5 weeks after streptozotocin (STZ) treatment. Additionally, Intraperitoneal injections of angiotensin II (Ang II) or intragastric losartan (Los) were administered to assess the activities of AGTR1 and TRPV1. Two-dimensional echocardiography and tissue histopathology were used to assess cardiac function Western blot was used to detect the autophagic biomarkers Such as light chain 3 P62 and lysosomal-associated membrane protein 2 And transmission electron microscopy was used to count the number of autophagosomes. Results: Decreased expression of TRPV1 and autophagic hallmarks and reduced numbers of autophagolysosomes as well as increased expression of angiotensin converting enzyme 1 and AGTR1 were observed in diabetic hearts. Blocking AGTR1 with Los mimicked the QLQX-mediated improvements in cardiac function Alleviated myocardial fibrosis and enabled autophagy Whereas Ang II abolished the beneficial effects of QLQX in wild type diabetic mice but not in TRPV1-/- diabetic mice. Conclusions: QLQX may improve diabetic cardiac function by regulating AGTR1/ TRPV1-mediated autophagy in STZ-induced diabetic mice

    A novel nomogram to predict futile recanalization in patients with acute ischemic stroke undergoing mechanical thrombectomy

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    Background and objectiveFutile recanalization (FR) is defined as patients with acute ischemic stroke (AIS) due to large vessel occlusion who still exhibits functional dependence although undergoing successful mechanical thrombectomy (MT). We aimed to develop and validate a simple nomogram for predicting the probability of FR after MT treatment in AIS patients.MethodsClinical data of AIS patients in the Jrecan clinical trial in China from March 2018 to June 2019 were collected as the derivation set (n = 162). Meanwhile, clinical data of AIS patients who underwent MT in Baotou Central Hospital and Ningbo No.2 Hospital from 2019 to 2021 were collected as the validation set (n = 170). Multivariate logistic regression analysis was performed for all variables that had p < 0.2 in the univariate analysis in the derivation set. The independent risk factors of FR were further screened out and a nomogram was constructed. The performance of the nomogram was analyzed in the derivation and validation set using C-index, calibration plots, and decision curves.ResultsNo significant difference in FR rate was detected between the derivation set and the validation set [88/162 (54.32%) and 82/170 (48.23%), p = 0.267]. Multivariate logistic regression analysis showed that age ≥ 65 years old (OR = 2.096, 95%CI 1.024–4.289, p = 0.043), systolic blood pressure (SBP) ≥ 180 mmHg (OR = 5.624, 95%CI 1.141–27.717, p = 0.034), onset to recanalization time (OTR) ≥ 453 min (OR = 2.759, 95%CI 1.323–5.754, p = 0.007), 24 h intracerebral hemorrhage (ICH; OR = 4.029, 95%CI 1.844 ~ 8.803, p < 0.001) were independent risk factors for FR. The C-index of the nomogram of the derivation set and the verification set were 0.739 (95%CI 0.662~0.816) and 0.703 (95%CI 0.621~0.785), respectively.ConclusionThe nomogram composed of age, SBP, OTR, and 24 h ICH can effectively predict the probability of FR after MT in AIS patients
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