bluuebunny/crossref_metadata_2025_split huggingface dataset:
Desain kontrol adaptif L1 dengan band pass filter orde dua untuk pengendali vibrasi pada rotor helikopter
Authors: Gamar Farida , Kadir Rusdhianto Effendie Abdul , Jazidie Achmad 
Published: May 2023

Vibrasi pada helikopter menjadi konsentrasi tersendiri untuk terus ditingkatkan penanganannya. Hal ini dikarenakan selain dapat menyebabkan kerusakan struktur badan helikopter jika vibrasi yang dihasilkan terlalu besar juga berpengaruh pada kenyamanan pilot dan penumpang. Sistem vibrasi pada helicopter terdiri dari baling-baling, rotor mount, dan suspensi dimana terdapat damper sebagai peredam. Pada penelitian ini, digunakan damper semi aktif yang variabelnya dikontrol dengan menggunakan kontrol adaptif L1 berbasis analisis Fourier dari vibrasi yang dihasilkan oleh rotor. Analisis Fourier digunakan untuk mencari frekuensi cutoff vibrasi yang digunakan untuk penalaan pada kontrol adaptif L1. Hasil rancangan band pass filter orde 2 pada sistem dapat memperbaiki respon percepatan hingga 72.52% pada rotor mount dan 65.94% badan helicopter dalam waktu 2 detik. Hasil rancangan juga dapat menangani kesalahan perpindahan sebesar 55.6% pada rotor mount dan 55.56% pada badan helikopter dalam waktu 2 detik. Perbaikan respon percepatan pada badan helicopter yang mencapai 0 m/s2 telah memenuhi rekomendasi NASA untuk minimal percepatan pada sistem vibrasi helikopter.
ABSTRACT
Vibration in helicopters is a separate concentration to continue to improve its handling. This is because, in addition to causing damage to the helicopter body structure if the vibration generated are too large, it also affects the comfort of pilot and passengers. The vibration system on the helicopter consists of propeller, rotor mount, and suspension where there are dampers as dampers. In this research, a semi-active damper is used whose variables are controlled using Fourier analysis-based L1 adaptive control of the vibrations generated by the rotor. Fourier analysis is used to find the cutoff frequency of vibration used for tuning the L1 adaptive control. The results of the second-order band pass filter design in the system can improve the acceleration response up to 72.52% on the rotor mount and 65.94% of the helicopter body within 2 seconds. The design results can also handle displacement errors of 55.6% on the rotor mount and 55.56% on the helicopter body within 2 seconds. The improvement of the acceleration response on the helicopter body which reaches 0 m/s2 has required NASA's recommendations for minimum acceleration in helicopter vibration systems.
Quality evaluation of compounds in leaves of six Taxus species based on UPLC-MS/MS and chemometrics
Authors: Cai Qingzhu , Song Qiang , Jiang Kunxia , Lin Yao , Zhang Ying , Zhang Jirong , Lin Shuqing , Huang Lina , Xue Qihuang , Huang Zehao , Xu Wen , Xu Wei , Yam Mun Fei 
Published: May 2023

Introduction:Taxus species are used as medicinal plants all over the world. The leaves of Taxus species are sustainable medicinal resources that are rich in taxoids and flavonoids. However, traditional identification methods cannot effectively identify Taxus species on the basis of leaces used as raw medicinal materials, because their appearance and morphological characteristics are almost the same, and the probability of error identification increases in accordance with the subjective consciousness of the experimenter. Moreover, although the leaves of different Taxus species have been widely used, their chemical components are similar and lack systematic comparative research. Such a situation is challenging for quality assessment.Materials and methods: In this study, ultra-high-performance liquid chromatography coupled with triple quadrupole mass spectrometry combined with chemometrics was applied for the simultaneous determination of eight taxoids, four flavanols, five flavonols, two dihydroflavones, and five biflavones in the leaves of six Taxus species, namely, T. mairei, T. chinensis, T. yunnanensis, T. wallichiana, T. cuspidata, and T. media. Chemometric methods, including hierarchical cluster analysis, principal component analysis, orthogonal partial least squares-discriminate analysis, random forest iterative modeling, and fisher linear discriminant analysis, were utilized to differentiate and evaluate the six Taxus species.Results: This proposed method exhibited good linearity (R2 = 0.9999–0.9972) with a lower quantification limits of 0.94–3.05 ng/mL for all analytes. The intra- and inter-day precisions were within 6.83%. Six compounds, namely, 7-xylosyl-10-deacetyltaxol, ginkgetin, rutin, aromadendrin, 10-deacetyl baccatin III, and epigallocatechin, were identified through chemometrics for the first time. These compounds can be used as important chemical markers to distinguish the above six Taxus species rapidly.Conclusion: This study established a method for determination of the leaves of six Taxus species, and revealing the differences in the chemical components of these six Taxus species.
The prognostic value of deep earlobe creases in patients with acute ischemic stroke
Authors: Xu Jiaping , Wang Lixuan , Zhang Chunqing , Wang Jiayun , Zheng Danni , Huang Yaqian , Zhang Xia , You Shoujiang , Cao Yongjun , Liu Chun-Feng 
Published: May 2023

Background and purposeData on earlobe crease (ELC) among patients with acute ischemic stroke (AIS) are limited. Here, we determined the frequency and characteristics of ELC and the prognostic effect of ELC among AIS patients.MethodsA total of 936 patients with acute AIS were enrolled during the period between December 2018 and December 2019. The patients were divided into those without and with ELC, unilateral and bilateral ELC, and shallow and deep ELC, according to the photographs taken of the bilateral ears. Logistic regression models were used to estimate the effect of ELC, bilateral ELC, and deep ELC on poor functional outcomes at 90 days (a modified Rankin Scale score ≥2) in AIS patients.ResultsAmong the 936 AIS patients, there were 746 (79.7%) patients with ELC. Among patients with ELC, there were 156 (20.9%) patients with unilateral ELC and 590 (79.1%) with bilateral ELC and 476 (63.8%) patients with shallow ELC and 270 (36.2%) with deep ELC. After adjusting for age, sex, baseline NIHSS score, and other potential covariates, patients with deep ELC were associated with a 1.87-fold [odds ratio (OR) 1.87; 95% confidence interval (CI), 1.13–3.09] and 1.63-fold (OR 1.63; 95%CI, 1.14–2.34) increase in the risk of poor functional outcome at 90 days in comparison with those without ELC or shallow ELC.ConclusionELC was a common phenomenon, and eight out of ten AIS patients had ELC. Most patients had bilateral ELC, and more than one-third had deep ELC. Deep ELC was independently associated with an increased risk of poor functional outcome at 90 days.
Rapid environmental changes in the Lake Qinghai basin during the late Holocene
Authors: Wang Chen , Qiu Yahui , Fan Fenglei , Li Baosheng , Niu Dongfeng , Shu Peixian 
Published: May 2023

The Lake Qinghai Basin is sensitive to global and regional climate change because of its unique geographical location. It is the hotspot for paleoclimate research in East Asia. In this study, we reconstructed the environmental evolution of the Lake Qinghai since ∼9 ka by using a high-resolution peat and fluvial-lacustrine record (Laoyinggou profile) obtained at the foot of Nanshan Mountain. Based on 8 AMS14C dates and lithology, loss on ignition (LOI), total organic matter (TOC), X-ray fluorescence (XRF) core-scanning measurements, ratio of total organic carbon to nitrogen (TOC/TN), and sediment particle sorting coefficients, we show that during the Middle Holocene (∼9–4.4 ka BP) this region was primarily dominated by the Asian summer monsoon, with a consistent, warm, and humid environment. By contrast, during the late Holocene (4.4 ka to present), the climatic context in this area fluctuated dramatically at the millennial scales. The low TOC content, lower TOC/TN ration and strong hydroclimatic indicate six rapid climate change events, which occurred at ∼4.0 ka, ∼3.6 ka, ∼3.2 ka, ∼2.8 ka, ∼2.1 ka, and ∼1.4 ka, all of which coincided to cold episodes in the North Atlantic Ocean.
Strain fields of Ms >6.0 earthquakes in Menyuan, Qinghai, China
Authors: Luo Guofu , Ding Fenghe , Xu Yingcai , Luo Hengzhi , Li Wenjun 
Published: May 2023

In predicting earthquakes, it is a major challenge to capture the time factor and spatial isoline anomalies, and understand their physical processes, of the seismic strain field before a strong earthquake. In this study, the seismic strain field was used as representative of seismic activity. The natural orthogonal function expansion method was used to calculate the seismic strain field before the Menyuan Ms 6.4 earthquakes in 1986 and 2016, and the Ms 6.9 earthquake in 2022. Time factor and spatial isoline anomaly of the strain field before each earthquake was extracted. We also compared the evolution of the strain field with numerical simulation results under the tectonic stress system at the source. The results showed that the time factor before the earthquakes had high or low value anomalies, exceeding the mean square error of the stable background. The anomalies were concentrated in the first four typical fields of the strain field, which has multiple components. The abnormal contribution rate of the first typical field is the largest (accounting for 42%–49% of the total field). The long- and medium-term anomalies appear 3-4, and 1-2 years before the earthquake, respectively. There were no short or immediate-term anomalies within 3 months of the earthquake. In addition, during the evolution of the strain field, the abnormal area of the spatial isoline changed with the change in time. Usually, the intersection area of the two isoseismic lines of strain accumulation and strain release becomes a potential location for strong earthquakes. Finally, we found that the high strain field values of the 1986 and 2016 Ms 6.4 earthquakes were equivalent to the numerical simulation results, while the high strain field values of the 2022 Menyuan Ms 6.9 earthquakes were slightly different, but within the accepted error range. These results indicate that the two methods are consistent. We have shown that the natural orgthagonal method can be used to obtain the spatiotemporal anomaly information of strain field preceding strong earthquakes.
Study on the improvement of the open TBM system and supporting equipment based on the Gaojiapu Coal Mine
Authors: Liu Yexian , Ren Dengjun , Zhou Changkuan , Qiu Huafu , Ding Ziwei , Liang Chao 
Published: May 2023

In order to cope with multi-dimensional mine disasters in deep mines, enhance the adaptability of the open tunnel-boring machine (TBM) to the actual mine working face environment, and improve the excavation speed of the open TBM, based on the excavation project of Gaojiapu Coal Mine in Zhengtong Coal Industry, Shaanxi Province, this paper comprehensively considers the difficulties encountered by the TBM in the excavation process and improves the open TBM system and its supporting equipment. The research shows that removing the redundant system and supporting equipment of the open TBM can effectively solve the difficulties of the TBM entering the mine, such as loading and unloading, and turning; optimizing the open TBM shield, shortening the main beam, and setting the support platform and jumbolter system on the main beam can deal with the problem that the TBM support is not timely and easy to jam. Opening circular holes and installing slag cleaning guide plates on the main beam of the open TBM can timely clean up the waste slag on the main beam and protect the main beam from deformation. Installing a slag cleaning bucket wheel machine between the main beam of the open TBM and the trailer can reduce the accumulation of waste slag on the road ahead. Compared with ordinary excavation construction technology, the monthly average footage level of the open TBM after technical improvement is 300.88 m, which is 3.8 times that of the rock roadway general excavation and 1.6 times that of the rock roadway comprehensive excavation.
Identifying and analyzing the key genes shared by papillary thyroid carcinoma and Hashimoto’s thyroiditis using bioinformatics methods
Authors: Liu Ting-ting , Yin De-tao , Wang Nan , Li Na , Dong Gang , Peng Meng-fan 
Published: May 2023

BackgroundHashimoto’s thyroiditis (HT) is a chronic autoimmune disease that poses a risk factor for papillary thyroid carcinoma (PTC). The present study aimed to identify the key genes shared by HT and PTC for advancing the current understanding of their shared pathogenesis and molecular mechanisms.MethodsHT- and PTC-related datasets (GSE138198 and GSE33630, respectively) were retrieved from the Gene Expression Omnibus (GEO) database. Genes significantly related to the PTC phenotype were identified using weighted gene co-expression network analysis (WGCNA). Differentially expressed genes (DEGs) were identified between PTC and healthy samples from GSE33630, and between HT and normal samples from GSE138198. Subsequently, functional enrichment analysis was performed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Transcription factors and miRNAs regulating the common genes in PTC and HT were forecasted using the Harmonizome and miRWalk databases, respectively, and drugs targeting these genes were investigated using the Drug-Gene Interaction Database (DGIdb). The key genes in both GSE138198 and GSE33630 were further identified via Receiver Operating Characteristic (ROC) analysis. The expression of key genes was verified in external validation set and clinical samples using quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC).ResultsIn total, 690 and 1945 DEGs were associated with PTC and HT, respectively; of these, 56 were shared and exhibited excellent predictive accuracy in the GSE138198 and GSE33630 cohorts. Notably, four genes, Alcohol Dehydrogenase 1B (ADH1B), Active BCR-related (ABR), alpha-1 antitrypsin (SERPINA1), and lysophosphatidic acid receptor 5 (LPAR5) were recognized as key genes shared by HT and PTC. Subsequently, EGR1 was identified as a common transcription factor regulating ABR, SERPINA1, and LPAR5 expression. These findings were confirmed using qRT-PCR and immunohistochemical analysis.ConclusionFour (ADH1B, ABR, SERPINA1, and LPAR5) out of 56 common genes exhibited diagnostic potential in HT and PTC. Notably, this study, for the first time, defined the close relationship between ABR and HT/PTC progression. Overall, this study provides a basis for understanding the shared pathogenesis and underlying molecular mechanisms of HT and PTC, which might help improve patient diagnosis and prognosis.
Postoperative hypoparathyroidism after thyroid operation and exploration of permanent hypoparathyroidism evaluation
Authors: Wang Xi , Wang Shun-lan , Cao Yang , Li Chun-qiao , He Weiping , Guo Zhu-ming 
Published: May 2023

BackgroundTo investigate the risk factors for hypoparathyroidism, discuss the prevention of postoperative hypoparathyroidism, and explore permanent postoperative hypoparathyroidism evaluation (PPHE).MethodsA total of 2,903 patients with thyroid nodules were treated between October 2012 and August 2015. Serum calcium and intact parathyroid hormone (iPTH) levels were measured at 1 day, 1 month, and 6 months postoperatively. The incidence and management of hypoparathyroidism were analyzed. The PPHE was established based on the risk factors and clinical practice.ResultsA total of 637 (21.94%) patients developed hypoparathyroidism, and 92.15% of them had malignant nodules. The incidence rates of transient and permanent hypoparathyroidism were 11.47% and 10.47%, respectively. The iPTH level was lower in patients with malignant nodules who underwent total thyroidectomy (TT) and central-compartment neck dissection (CND). These factors were independently associated with the recovery rate of parathyroid function. The formula for PPHE is as follows: {iPTH} + {sCa} + {surgical procedure} + {reoperation} + {pathologic type}. A scoring system was developed, and we scored low, middle, and high risk of permanent postoperative hypoparathyroidism as 4–6, 7–9, and 10–13, respectively. The differences in the recovery rates of parathyroid function in several risk groups were statistically significant (p &lt; 0.001).ConclusionSimultaneous TT and CND is a risk factor for hypoparathyroidism. The reoperation is not associated with hypoparathyroidism. Identification of parathyroid glands in situ and preservation of their vascular pedicles are key factors in managing hypoparathyroidism. PPHE can forecast the risk of permanent postoperative hypoparathyroidism well.
Metabolic syndrome as risk factor for left ventricular hypertrophy in children with chronic kidney disease
Authors: Drożdż Monika , Moczulska Anna , Rudziński Andrzej , Drożdż Dorota 
Published: May 2023

BackgroundThe metabolic syndrome (MS), a cluster of clinical and biochemical abnormalities including insulin resistance, dyslipidemia and hypertension, is often diagnosed in chronic kidney disease (CKD) children. Left ventricular hypertrophy (LVH) is a major target organ damage in hypertension and an important cardiovascular risk factor in CKD patients. We aimed to identify the most significant risk factors of LVH in children with CKD.MethodsChildren with CKD stage 1-5 were enrolled in the study. MS was diagnosed according to De Ferranti (DF) as ≥3 from 5 criteria. Ambulatory blood pressure measurements (ABPM) and echocardiographic evaluation were performed. LVH was defined as ≥95th percentile of LV mass index related to height and age. Clinical and laboratory parameters included: serum albumin, Ca, HCT, cystatin C, creatinine, estimated glomerular filtration rate (eGFR) based on Schwartz formula, triglycerides, high-density lipoprotein (HDL), proteinuria, BMI standard deviation score (SDS), height SDS, waist circumference, ABPM data.Results71 children (28 girls/43 boys) with median age 14.05 (25%-75%:10.03-16.30) years and median eGFR 66.75 (32.76-92.32) ml/min/1.73m2 were evaluated. CKD stage 5 was diagnosed in 11 pts (15.5%). MS (DF) was diagnosed in 20 pts (28.2%). Glucose ≥ 110 mg/dL was present in 3 pts (4.2%); waist circumference ≥75th pc in 16 pts (22.5%); triglycerides ≥ 100 mg/dL in 35 pts (49.3%); HDL &lt; 50mg/dL in 31 pts (43.7%) and BP ≥ 90th pc in 29 pts (40.8%), respectively. LVH was detected in 21 (29.6%) children. In univariate regression the strongest risk factor for LVH was CKD stage 5 (OR 4.9, p=0.0019) and low height SDS (OR 0.43,p=0.0009). In stepwise multiple logistic regression analysis (logit model) of the most important risk factors for LVH in CKD children, only three were statistically significant predictors: 1)MS diagnosis based on DF criteria (OR=24.11; 95%CI 1.1-528.7; p=0.043; Chi2 = 8.38,p=0.0038); 2), high mean arterial pressure (MAP SDS) in ABPM (OR=2.812; 95%CI 1.057-7.48; p=0.038;Chi2 = 5.91, p=0.015) and 3) low height SDS (OR=0.078; 95%CI 0.013-0.486;p=0.006; Chi2 = 25.01, p&lt;0.001).ConclusionsIn children with chronic kidney disease LVH is associated with the cluster of multiple factors, among them the components of MS, hypertension, stage 5 CKD and growth deficit were the most significant.
Research progress of aqueous Zn–CO2 battery: design principle and development strategy of a multifunctional catalyst
Authors: Guo Wenqi , Wang Yukun , Yi Qun , Devid Edwin , Li Xuelian , Lei Puying , Shan Wenlan , Qi Kai , Shi Lijuan , Gao Lili 
Published: May 2023

Aqueous Zn–CO2 battery possesses a large theoretical capacity of 820 mAh g-1 (5855 mAh cm-3) and high safety, showing a unique position in carbon neutrality and/or reduction and energy conversion and storage, which has developed rapidly in recent years. However, obstacles such as low value-added products, low current density, high overvoltage, and finite cycles impede its practical application. Cathode catalysts, as a key component, have a significant influence on gas cell performance. Despite many updated papers on cathode materials for aqueous Zn–CO2 batteries, a systematic summary has rarely been reported, and even less is mentioned about the design principle and development strategy for efficient catalysts. Relying on the structure and mechanism of the Zn–CO2 battery, this review discusses the research progress and existing challenges, and, more importantly, the design strategies and preparation methods of the efficient cathode are proposed, centering on material structure, charge distribution, and coordination environment. Finally, in this review, the opportunities for the development of a high-performance Zn–CO2 battery are highlighted, which enables enlightening the future exploration of next-generation energy storage systems.
Wildfire-related smoke inhalation worsens cardiovascular risk in sleep disrupted rats
Authors: Martin W. Kyle , Schladweiler M. C. , Oshiro W. , Smoot J. , Fisher A. , Williams W. , Valdez M. , Miller C. N. , Jackson T. W. , Freeborn D. , Kim Y. H. , Davies D. , Gilmour M. Ian , Kodavanti U. , Kodavanti P. , Hazari M. S. , Farraj A. K. 
Published: May 2023

IntroductionAs a lifestyle factor, poor sleep status is associated with increased cardiovascular morbidity and mortality and may be influenced by environmental stressors, including air pollution.MethodsTo determine whether exposure to air pollution modified cardiovascular effects of sleep disruption, we evaluated the effects of single or repeated (twice/wk for 4 wks) inhalation exposure to eucalyptus wood smoke (ES; 964 µg/m3 for 1 h), a key wildland fire air pollution source, on mild sleep loss in the form of gentle handling in rats. Blood pressure (BP) radiotelemetry and echocardiography were evaluated along with assessments of lung and systemic inflammation, cardiac and hypothalamic gene expression, and heart rate variability (HRV), a measure of cardiac autonomic tone.Results and DiscussionGH alone disrupted sleep, as evidenced by active period-like locomotor activity, and increases in BP, heart rate (HR), and hypothalamic expression of the circadian gene Per2. A single bout of sleep disruption and ES, but neither alone, increased HR and BP as rats transitioned into their active period, a period aligned with a critical early morning window for stroke risk in humans. These responses were immediately preceded by reduced HRV, indicating increased cardiac sympathetic tone. In addition, only sleep disrupted rats exposed to ES had increased HR and BP during the final sleep disruption period. These rats also had increased cardiac output and cardiac expression of genes related to adrenergic function, and regulation of vasoconstriction and systemic blood pressure one day after final ES exposure. There was little evidence of lung or systemic inflammation, except for increases in serum LDL cholesterol and alanine aminotransferase. These results suggest that inhaled air pollution increases sleep perturbation-related cardiovascular risk, potentially in part by increased sympathetic activity.