The blades that play a key role to collect wind energy are the most critical components of a wind turbine system. Meanwhile, they are also the parts most susceptible to damage. Structural health ...monitoring (SHM) system has been proposed to continuously monitor the wind turbine. Nevertheless, no system has yet been developed to a stage compatible with the requirements of commercial wind turbines. Therefore, full-scale structural testing is the main means available so far for validating the comprehensive performance of wind turbine blades. It is now normally used as part of a blade certification process. It also allows an insight into the failure mechanisms of wind turbine blades, which are essential to the success of SHM. Furthermore, it provides a unique opportunity to exercise SHM and non-destructive testing (NDT) techniques. Recognizing these practical significances, this paper therefore aims to carry out an extensive review of full-scale structural testing of wind turbine blades, including static testing and fatigue testing. In particular, the current status in China is presented. One focus of this review is on the failure mechanisms of wind turbine blades, which are vital for optimizing the design of themselves as well as the design of their SHM system. Another focus is on the strengths and weaknesses of various SHM and NDT techniques, which are useful for evaluating their applicability on wind turbine blades. In addition, recent advances in photogrammetry and digital image correlation have allowed new opportunities for blade monitoring. These techniques are currently being explored on a few wind turbine blade applications and can provide a wealth of additional information that was previously unobtainable. These works are also summarized in this paper in order to discover the pros and cons of these techniques.
Using a low background data sample of 9.7×10^{5} J/ψ→γη^{'}, η^{'}→γπ^{+}π^{-} events, which are 2 orders of magnitude larger than those from the previous experiments, recorded with the BESIII ...detector at BEPCII, the decay dynamics of η^{'}→γπ^{+}π^{-} are studied with both model-dependent and model-independent approaches. The contributions of ω and the ρ(770)-ω interference are observed for the first time in the decays η^{'}→γπ^{+}π^{-} in both approaches. Additionally, a contribution from the box anomaly or the ρ(1450) resonance is required in the model-dependent approach, while the process specific part of the decay amplitude is determined in the model-independent approach.
The cross sections of e^{+}e^{-}→π^{+}π^{-}h_{c} at center-of-mass energies from 3.896 to 4.600 GeV are measured using data samples collected with the BESIII detector operating at the Beijing ...Electron Positron Collider. The cross sections are found to be of the same order of magnitude as those of e^{+}e^{-}→π^{+}π^{-}J/ψ and e^{+}e^{-}→π^{+}π^{-}ψ(2S), but the line shape is inconsistent with the Y states observed in the latter two modes. Two structures are observed in the e^{+}e^{-}→π^{+}π^{-}h_{c} cross sections around 4.22 and 4.39 GeV/c^{2}, which we call Y(4220) and Y(4390), respectively. A fit with a coherent sum of two Breit-Wigner functions results in a mass of (4218.4_{-4.5}^{+5.5}±0.9) MeV/c^{2} and a width of (66.0_{-8.3}^{+12.3}±0.4) MeV for the Y(4220), and a mass of (4391.5_{-6.8}^{+6.3}±1.0) MeV/c^{2} and a width of (139.5_{-20.6}^{+16.2}±0.6) MeV for the Y(4390), where the first uncertainties are statistical and the second ones systematic. The statistical significance of Y(4220) and Y(4390) is 10σ over one structure assumption.
The spin and parity of the Z_{c}(3900)^{±} state are determined to be J^{P}=1^{+} with a statistical significance larger than 7σ over other quantum numbers in a partial wave analysis of the process ...e^{+}e^{-}→π^{+}π^{-}J/ψ. We use a data sample of 1.92 fb^{-1} accumulated at sqrts=4.23 and 4.26 GeV with the BESIII experiment. When parametrizing the Z_{c}(3900)^{±} with a Flatté-like formula, we determine its pole mass M_{pole}=(3881.2±4.2_{stat}±52.7_{syst}) MeV/c^{2} and pole width Γ_{pole}=(51.8±4.6_{stat}±36.0_{syst}) MeV. We also measure cross sections for the process e^{+}e^{-}→Z_{c}(3900)^{+}π^{-}+c.c.→J/ψπ^{+}π^{-} and determine an upper limit at the 90% confidence level for the process e^{+}e^{-}→Z_{c}(4020)^{+}π^{-}+c.c.→J/ψπ^{+}π^{-}.
•We present a potential assessment model based on response of fish to their habitat.•It links hydrologic, physical and chemical habitat gradients to fish attributes.•Requiring a little assemblage ...information and expertise makes it practical.•Habitat and fish were monitored at 144 sites with 5084 fish tested.•Application results were well validated by references and freshwater transparency.
Aquatic ecological rehabilitation is increasingly attracting considerable public and research attention. An effective method that requires less data and expertise would help in the assessment of rehabilitation potential and in the monitoring of rehabilitation activities as complicated theories and excessive data requirements on assemblage information make many current assessment models expensive and limit their wide use. This paper presents an assessment model for restoration potential which successfully links hydrologic, physical and chemical habitat factors to fish assemblage attributes drawn from monitoring datasets on hydrology, water quality and fish assemblages at a total of 144 sites, where 5084 fish were sampled and tested. In this model three newly developed sub-models, integrated habitat index (IHSI), integrated ecological niche breadth (INB) and integrated ecological niche overlap (INO), are established to study spatial heterogeneity of the restoration potential of fish assemblages based on gradient methods of habitat suitability index and ecological niche models. To reduce uncertainties in the model, as many fish species as possible, including important native fish, were selected as dominant species with monitoring occurring over several seasons to comprehensively select key habitat factors. Furthermore, a detrended correspondence analysis (DCA) was employed prior to a canonical correspondence analysis (CCA) of the data to avoid the “arc effect” in the selection of key habitat factors. Application of the model to data collected at Jinan City, China proved effective reveals that three lower potential regions that should be targeted in future aquatic ecosystem rehabilitation programs. They were well validated by the distribution of two habitat parameters: river width and transparency. River width positively influenced and transparency negatively influenced fish assemblages. The model can be applied for monitoring the effects of fish assemblage restoration. This has large ramifications for the restoration of aquatic ecosystems and spatial heterogeneity of fish assemblages all over the world.
To summarize the clinical manifestations and prognostic factors of patients with hepatic amyloidosis in a single center.
The clinical data of 28 primary systemic light chain amyloidosis cases with ...liver involvement in our center from October 2012 to January 2023 were retrospectively analyzed. The main clinical manifestations and prognostic factors were studied. Statistical analysis were performed using the χ(2) test, Fisher's exact test, Wilcoxon rank test, or Kaplan-Meier survival curve log-rank test according to the different data.
The main clinical manifestations of patients with liver involvement were abdominal distension, hepatomegaly, and edema. CD56 and chemokine receptor 4 protein expression accounted for 52% (13/25) and 56% (14/25). 64.3% (9/14) patients were combined with t (11,14), and 21.4% (3/14) patients were positive for 1q21 (+), and no patients were detected with del(17p). Univariate analysis showed that Mayo 2004 and 2012 stages and total bilirubin (TBil) ≥34.2 μmol/L were associated with pr
Using 567 pb^{-1} of data collected with the BESIII detector at a center-of-mass energy of sqrts=4.599 GeV, near the Λ_{c}^{+}Λover ¯_{c}^{-} threshold, we study the singly Cabibbo-suppressed ...decays Λ_{c}^{+}→pπ^{+}π^{-} and Λ_{c}^{+}→pK^{+}K^{-}. By normalizing with respect to the Cabibbo-favored decay Λ_{c}^{+}→pK^{-}π^{+}, we obtain ratios of branching fractions: B(Λ_{c}^{+}→pπ^{+}π^{-})/B(Λ_{c}^{+}→pK^{-}π^{+})=(6.70±0.48±0.25)%, B(Λ_{c}^{+}→pϕ)/B(Λ_{c}^{+}→pK^{-}π^{+})=(1.81±0.33±0.13)%, and B(Λ_{c}^{+}→pK^{+}K_{non-ϕ}^{-})/B(Λ_{c}^{+}→pK^{-}π^{+})=(9.36±2.22±0.71)×10^{-3}, where the uncertainties are statistical and systematic, respectively. The absolute branching fractions are also presented. Among these measurements, the decay Λ_{c}^{+}→pπ^{+}π^{-} is observed for the first time, and the precision of the branching fraction for Λ_{c}^{+}→pK^{+}K_{non-ϕ}^{-} and Λ_{c}^{+}→pϕ is significantly improved.
Risk factors related to residual cancer or lymph node metastasis after endoscopic non-curative resection of early colorectal cancer were analyzed to predict the risk of residual cancer or lymph node ...metastasis, optimize the indications of radical surgical surgery, and avoid excessive additional surgical operations.
Clinical data of 81 patients who received endoscopic treatment for early colorectal cancer in the Department of Endoscopy, Cancer Hospital, Chinese Academy of Medical Sciences from 2009 to 2019 and received additional radical surgical surgery after endoscopic resection with pathological indication of non-curative resection were collected to analyze the relationship between various factors and the risk of residual cancer or lymph node metastasis after endoscopic resection.
Of the 81 patients, 17 (21.0%) were positive for residual cancer or lymph node metastasis, while 64 (79.0%) were negative. Among 17 patients with residual cancer or positive lymph node metastasis, 3 patients had only residual canc
Breast cancer (BC) is one of the most common fatal cancers. Recent studies have identified the vital roles of long non-coding RNAs (lncRNAs) in the development and progression of BC. This research ...aimed to investigate the underlying mechanisms of lncRNA TTN-AS1 in the metastasis of BC.
TTN-AS1 expression of tissues was detected by Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) in 50 BC patients. Wound healing assay and transwell assay were used to observe the phenotypic alteration of BC cells after knockdown or overexpression of TTN-AS1. Moreover, RT-qPCR and Western blot assay were performed to discover the potential targets of TTN-AS1 in BC.
TTN-AS1 expression in BC samples was significantly higher than that of the adjacent tissues. Besides, the migration and invasion of BC cells were markedly inhibited after TTN-AS1 was silenced, while promoted after TTN-AS1 overexpression. In addition, a remarkable decrease of DGCR8 was observed after TTN-AS1 was inhibited in BC cells, while DGCR8 was upregulated after overexpression of TTN-AS1. Furthermore, DGCR8 expression showed significant enhancement in BC tissues and was positively associated with TTN-AS1 level.
Our study uncovered a new oncogene in BC and suggested that TTN-AS1 could enhance BC cell migration and invasion via sponging DGCR8, which provided a novel therapeutic target for the treatment of breast cancer.
To investigate the endoscopic combined serological diagnosis strategy for G1 and G2 gastric neuroendocrine neoplasms (G-NENs), and to evaluate the safety, short-term, and long-term efficacy of two ...endoscopic treatment procedures: endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD).
This study retrospectively analyzed the clinical data of 100 consecutive patients with G-NENs who were hospitalized at the Cancer Hospital of the Chinese Academy of Medical Sciences from January 2011 to October 2023. These patients underwent endoscopic treatment, and propensity score matching (PSM) was used to compare clinicopathological characteristics, as well as short-term and long-term efficacy of lesions in the EMR group and ESD group before and after treatment.
Among the 100 patients with G-NENs, the median age was 54 years old. Before surgery, 29 cases underwent endoscopic combined serological examination, and 24 of them (82.2%) had abnormally elevated plasma chromogranin A. The combined diagnostic
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