bluuebunny/crossref_metadata_2025 huggingface dataset:
Pattern and Extent of Coronary Artery Disease in Patients of Ischemic Heart Disease aged 40 Years or less
Authors: Ahmed Moeen Uddin , Hossain Solaiman , Alam M Shahidul , Parvez Md Shahimur , Debnath Debashish , Rahman Khan Md Mahidur
Published: April 2022

Background: Atherosclerotic coronary artery disease is rare in young adults aged 40 years or less. However, South Asia is among the top 3 of the countries with highest proportion of cases of first acute coronary syndrome events occurring at age 40 years or less. This study was to explore the extent and pattern of angiographic coronary artery disease among patients of ischemic heart disease aged 40 years or less.
Methods: This cross-sectional retrospective descriptive study included 140 patients who had coronary angiography for ischemic heart disease at the Department of Cardiology of Enam Medical College between July 2012 and December 2020. Coronary angiography was analyzed with particular attention to the extent of involvement of major epicardial coronary arteries including significant branch involvement.
Results: Of the 140 patients included in the study - aged 18-40 years (mean 35.90 and SD 4.05) and 59.28% in the 36-40 years age group – 85% were male. Coronary angiogram revealed Single Vessel Disease in 39.29%, Double Vessel Disease in 25.72%, Triple Vessel disease in 23.57%, normal Coronaries in 9.28%. Left Anterior descending territory was most involved - 94 (67.14%) patients having significant stenosis in the main trunk and/or one or more major branches. Overall, 23(16.43%) of the whole cohort of patients had multiple branch involvements in the three coronary artery territories.
Conclusion: In patients aged up to 40 years with ischemic heart disease, significant coronary artery disease burden was seen, including a significant proportion with multi-vessel disease and a high level of branch involvement in all the principal epicardial coronary territories. This indicates a high burden of disease in a relatively young age group, with significant implications for long term management over and beyond reperfusion/revascularization efforts.
Cardiovasc j 2022; 14(2): 103-110
Adult Congenital Heart Disease and Percutaneous Interventions : Analysis of Cases over five years in a Bangladeshi Center
Authors: Fatema Nurun Nahar
Published: April 2022

Background: In recent year ‘s considerable progress has been made in the early diagnosis and treatment of congenital heart disease (CHD) and a significant number of children are expected to survive into adulthood after completion of treatment. This has created a scope of a substantial population of patients with adult congenital heart disease. In Bangladesh, milder or simple from of congenital heart diseases are prevalent among populations but palliated and treated cases of CHD are gradually increasing the load of work for adult congenital heart disease (ACHD) professionals. Many of these cases can be treated by transcatheter intervention with excellent outcome.
Methods: This is a retrospective study conducted in a tertiary level cardiac hospitals of Bangladesh from January 2015 to December 2020. All cases aging 18 years and above were included who had undergone cardiac catheterization or percutaneous interventions. Data were collected from Echocardiography department, Catheterization Laboratory and indoor department. Follow up data were collected from echocardiography and outpatient department.
Results: Total Two hundred Ninety-four cases were enrolled for cardiac catheterization. Two hundred eighteen cases had various types of intervention. Most of the cases were in 18-25 years age group. Among shunt lesions, 165 cases (56.12%) had atrial septal defect (ASD), 48(22.02%) had ventricular septal defect (VSD), 32 (14.67%) had patent ductus arteriosus (PDA), and 4(1.83%) had patent foramen ovale (PFO). Device closure was performed in 120(55.04%) cases of ASD, 13(5.96%) cases of VSD, 30 (13.76%) cases of PDA and in 4(1.83%) cases of PFO. Nineteen (8.72%) had valvuloplasty for pulmonary stenosis (PS), 2 (0.68%) had valvuloplasty for aortic stenosis (AS), 2(0.068%) had coarctoplasty for coarctation of the aorta (CoA), 4 (1.83%) had percutaneous pulmonary valve implantation (PPVI). Seventeen (7.79%) cases had double intervention of ASD device closure and pulmonary stenosis, 5 (2,29%) cases had ASD and PDA device closure and 2 (0.92%) cases had PDA device closure and balloon coarctoplasty. ASD device was embolized in 4 cases. There were no other complications.
Conclusion: Outcome of intervention in ACHD was found safe and effective and no significant short or long-term complications were noticed.
Cardiovasc j 2022; 14(2): 121-127
The RIFLE Classification: A Stratification Scheme for Patients of Acute Renal Failure after Coronary Artery Bypass Surgery
Authors: Idris Rumman , Khan Musa , Kamruzzaman Md , Hannan Abdul , Kabir Humayun , Jahan Nusrat
Published: April 2022

Background: Acute renal failure is linked to an increased risk of death and morbidity after cardiac surgery. Because there are no standard criteria for acute renal damage, there is a wide variation in the reports that have been published. The Acute Dialysis Quality Initiative Workgroup has developed new RIFLE criteria for acute renal dysfunction. The goal of current study was to appraise whether this definition of postoperative renal dysfunction after coronary artery bypass surgery (CABG) was accurate.
Methods: Fifty patients with critical coronary artery disease & undergoing CABG were enrolled in the study. Out of 50 patients, 25 patients had CABG with cardiopulmonary bypass (CPB) and remaining 25 underwent off pump CABG (OPCAB). Patients were distributed into various groups (based on the severity of renal impairment) using the RIFLE classification: Risk, Injury, Failure, Loss, End-stage kidney disease) depending on either serum creatinine level/ estimated glomerular filtration rate (eGFR) or urine output. The variation with 30 days-mortality, ICU stay and renal replacement therapy after CABG were identified.
Results: After CABG, 10% of patients experienced renal impairment, as per definitions of RIFLE classification. In this study, there is no significant difference in ARF (RIFLE classification-normal and risk) with or without use of CPB. However, incidence of RIFLE- injury and failure is higher in CPB group than no CPB group. The postoperative proportions of death and renal failure necessitating renal replacement therapy (RRT) were 2% (number of patients, 1 of 50) and 2% (1 of 50), respectively in RIFLE-failure. For the whole study cohort, the median duration of postoperative ICU stay was 4.0 days, with interquartile ranges of 3.0 to 7.0 days. All the patients of Rifle classification-injury and failure had prolonged ICU stay (5 or more days).
Conclusions: The RIFLE criteria are a useful tool for determining renal impairment after CABG. Increased renal replacement treatment, longer ICU stays, and a higher death rate are all linked to the severity of RIFLE classification.
Cardiovasc j 2022; 14(2): 150-156
Percutaneous Coronary Intervention of Bifurcation Lesion
Authors: Islam AHM Waliul , Talukder Shahabuddin , Munwar Sham , Reza AQM , Ahmed Tamzeed , Rahman Kazi Atikur
Published: April 2022

Bifurcation lesion whether it is left main (LM) stem disease with left main to left anterior descending artery (LM-LAD) or left main to left circumflex (LM-LCX), LAD-Diagonal or LCX-Obtuse marginal or right coronary artery- posterior descending artery (RCA-PDA); are not uncommon lesion type that needs to be revascularized either by percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) to establish the coronary flow and relieved patient anginal symptoms. Even though, many of the literature maintained non-inferiority of bifurcation lesion PCI over CABG and is Class IIb indication for PCI by coronary stent. In literature, bifurcation lesions commonly encountered in PCI and are regarded as most technically challenging lesions to treat, in up to 20% of PCI cases. With the advent of interventional procedures and the availability of cardiac catheterization laboratory facilities, skilled interventionist, many of the Bangladeshi patients are being treated for coronary artery diseases (CAD). With the advent of drug eluting stents, availability of IVUS (Intravascular Ultrasound), FFR (Fractional Flow Reserve) and individual expertise, treating bifurcation lesion may not be difficult task. Interventionist must be expert enough in doing PCI, before to proceed for bifurcation lesion PCI. We need to work together to develop common consensus in developing updated skill in treating bifurcation lesion which will prove bifurcation PCI in our population.
Cardiovasc j 2022; 14(2): 168-175
Cukorbetegek szülés körüli ellátásának aktuális kérdései a belgyógyász-diabetológus szemszögéből
Authors: Kerényi Zsuzsanna
Published: April 2022

Diabetesszel szövődött terhességben a hyperglykaemia kezelése döntő fontosságú a szülés során mind az anya, mind az újszülött szülészeti kimeneteli adatainak javítása szempontjából. Ez különösen jelentős 1-es típusú cukorbetegségben szenvedő anyák esetében, és minden olyan anyánál, aki inzulinkezelésre szorul a vá­randósság alatt. Szteroidok alkalmazása a koraszülés kockázatának kitett várandósoknál tovább bonyolítja a hyperglykaemia kezelését közvetlenül a szülés előtti időszakban, és szükségessé teszi az inzulinterápia megfelelő módosítását. A szülés alatti éhomra maradás igénye megfelelő folyadék-, glükóz- és inzulinkezelést igényel a szülést megelőző órákban. Császármetszés esetén a betegek az első étkezésig szintén infúziós kezelésre szorulhatnak. Egységes szülés körüli kezelési ajánlás hiányában a szerző áttekinti a nemzetközi irodalom diabeteses várandósok szülés körüli ellátására vonatkozó belgyógyászati kérdéseit. Az összefoglaló közlemény bemutatja a különböző típusú cu­korbetegségben szenvedő asszonyok in­zulinkezelésének sajátosságait a szülés előtt, alatt, és közvetlenül utána. Adagolási ütem­tervet ismertet azok számára, akik a szülés előtti időszakban koraszülés miatt, és tüdőérlelés céljából antenatalis szteroidkezelésre szorulnak. A közlemény kitér a szülés körüli vércukor-ellenőrzés, a folyamatos szövetközi glükózmonitorozás és a inzulinpumpa-kezelés alkalmazására és programozására is.
Development of a Quaternion-based algorithm to process data in robotics applications
Authors: Edwards David , Ashmore Jacqueline , Bhalerao Kishor , Buchanan J. Robert , Cass Jonathan , Downey Allen , Fehribach Joseph , Fertig Elena , Grand’Maison Jérôme , Murisic Nebojsa , Nangle John , Ockendon John , Phillips Joel , Posta Filippo , Raymond Christopher
Published: April 2022

To implement automated control of a robot arm, it is critical to have an accurate description of the arm's position, orientation, and velocity in 3-space. Such a description can be facilitated with data about how the arm is aligned with the gravitational and magnetic fields of the Earth (the Earth frame). Using various sensors, TIAX can provide data on the orientation of the Earth's gravitational field with respect to the body frame of the robot arm, as well as the angular velocities of each axis making up the body frame. In this work, we focus on the transformation of this data from the body frame into the Earth frame. We examine the transformations in four different contexts: Euler angles, quaternions, rotations about a single axis, and transition matrices. We find that the contexts that do not rely upon angle definitions are superior. Unfortunately, consumers often demand the contexts that do.
Evaporation and deposition in porous media
Authors: Sanaei Pejman , Breward Chris , Ellis Meredith , Han Saem , Holzer Benjamin , Ji Hangjie , El Kahza Hamad , Smith Stefan Llewelyn , Parsa Shima , Reynolds Harry , Troy Jerome , Witelski Thomas , Zhang Nachuan , Zyskin Maxim
Published: April 2022

In this work, we consider a porous material that is filled with a liquid solution containing molecules from multiple species with known starting concentrations. As the solvent evaporates, molecules from these species are left behind and deposited on the internal pore walls within the porous material. We seek to (i) examine the dependence of the mass distribution of molecules along the pore walls and the drying rate/time on the pore diameter, pore length, fluid wetting properties, and evaporation conditions; (ii) develop a model a porous structure that has a distribution of pore sizes and in which. fluid moves due to capillary force; and (iii) understand how the mass distribution of molecules change upon cycles of wetting and drying.
Evaluation of Stool Short Chain Fatty Acids Profiles in the First Year of Life With Childhood Atopy-Related Outcomes
Authors: Cheng Hsin Yue , Chan James Chun Yip , Yap Gaik Chin , Huang Chiung-Hui , Kioh Dorinda Yan Qin , Tham Elizabeth Huiwen , Loo Evelyn Xiu Ling , Shek Lynette P. C. , Karnani Neerja , Goh Anne , Van Bever Hugo P. S. , Teoh Oon Hoe , Chan Yiong Huak , Lay Christophe , Knol Jan , Yap Fabian , Tan Kok Hian , Chong Yap-Seng , Godfrey Keith M. , Chan Eric Chun Yong , Lee Bee Wah , Ta Le Duc Huy
Published: April 2022

Introduction

Short chain fatty acids (SCFAs) are the main intestinal intermediate and end products of metabolism of dietary fibers/polyphenols by the gut microbiota. The aim of this study was to evaluate the biological implication of stool SCFA profiles determined in the first year of life on the clinical presentation of allergic outcomes in childhood.

Methods

From the Growing Up in Singapore Toward healthy Outcomes (GUSTO) cohort, a sub-cohort of 75 participants was recruited. Scheduled questionnaire data was collected for cumulative prevalence of physician-diagnosed eczema, wheezing with the use of nebuliser, and allergen sensitization till the age of 8 years. Stool samples collected at week 3 and months 3, 6 and 12 were quantitated for 9 SCFAs using LC/MS/MS. SCFA data were grouped into lower (below the 25th) and higher (above the 75th percentiles) categories. Generalized Linear Mixed Models was employed to analyse longitudinal association between SCFAs and atopy-related outcomes.

Results

Children with lower stool butyric acid levels (≤25th percentile) over the first 3 time points had higher odds ratio (OR) for wheezing (adjOR = 14.6), eczema (adjOR = 13.2), food sensitization (adjOR = 12.3) and combined outcomes of both wheezing and eczema (adjOR = 22.6) till age 8 years, compared to those with higher levels (≥75 percentile). Additionally, lower longitudinal levels of propionic acid (≤25th percentile) over 4 time points in first year of life was associated with recurrent wheezing (≥2 episodes) till 8 years (adjOR = 7.4) (adj p < 0.05).

Conclusion

Our results suggest that relatively low levels of gut SCFAs in early life are associated with increased susceptibility to atopic-related outcomes in childhood.
miR-654-5p Contributes to the Activation and Proliferation of Hepatic Stellate Cells by Targeting RXRα
Authors: Ma Heming , Wang Xiaomei , Liu Xu , Wang Chang , Gao Xiuzhu , Niu Junqi
Published: April 2022

Liver fibrosis (LF) is a major disease that threatens human health. Hepatic stellate cells (HSCs) contribute directly to LF via extracellular matrix (ECM) secretion. Moreover, RXRα is an important nuclear receptor that plays a key regulatory role in HSC activation. Meanwhile, microRNAs (miRNAs) have been identified as significant regulators of LF development. In particular, miR-654-5p is involved in cellular migration and proliferation, and via bioinformatics analysis, has been identified as a potential factor that targets RXRα in humans and in mice. However, the precise relationship between miR-654-5p and RXRα in the context of LF, remains unknown and is the primary focus of the current study. To establish in vitro activated cell model human primary HSCs were cultured in vitro and LX-2 cells were stimulated with recombinant human TGF-β1. mRNA and protein levels of RXRα, miR-654-5p and fibrogenic genes were compared in quiescent and activated HSCs. Moreover, after transfected with miR-654-5p mimics, the expression changes of above related genes in LX-2 cells were estimated. Meanwhile, cell proliferation and apoptosis were detected in miR-654-5p overexpressed LX-2 cells. Simultaneously, the targeted binding between miR-654-5p and RXRα was verified in LX-2 cells. Carbon tetrachloride (CCl4)-induced mouse model with liver fibrosis was use to research the role of the miR-654-5p in vitro. Our results show that miR-654-5p expression levels increased in activated human HSCs and TGFβ-treated LX-2 cells. Moreover, miR-654-5p mimics markedly promoted LX-2 cell proliferation while inhibiting their apoptosis. Accordingly, the expression levels of RXRα are decreased in activated HSCs and LX-2 cells. Additionally, dual-luciferase reporter assay results reveal direct targeting of RXRα by miR-654-5p. Similarly, in vivo miR-654-5p overexpression aggravates LF in mice that are intraperitoneally injected with CCl4. Taken together, our findings elucidated a novel molecular mechanism with potential use for treatment of LF.
Exosomes Derived From Human Gingival Mesenchymal Stem Cells Attenuate the Inflammatory Response in Periodontal Ligament Stem Cells
Authors: Sun Jiayao , Wang Zhiguo , Liu Peng , Hu Yingzhe , Li Tingting , Yang Jianbo , Gao Pengyu , Xu Quanchen
Published: April 2022

This study aimed to explore the effects of exosomes derived from human gingival mesenchymal stem cells (GMSC-Exo) on the inflammatory response of periodontal ligament stem cells (PDLSCs) in an inflammatory microenvironment in order to restore the regenerative potential of PDLSCs, which promotes periodontal tissue regeneration in patients with periodontitis. Periodontitis is a chronic infectious disease characterized by periodontal tissue inflammation and alveolar bone destruction. PDLSCs are regarded as promising seed cells for restoring periodontal tissue defects because of their ability to regenerate cementum/PDL-like tissue and alveolar bone. However, PDLSCs in the inflammatory environment show significantly attenuated regenerative potential. GMSC-Exo have been reported to have anti-inflammatory and immunosuppressive properties. In this study, we investigated the effects of GMSC-Exo on the inflammatory response of PDLSCs induced by lipopolysaccharides (LPS). LPS was used to simulate the inflammatory microenvironment of periodontitis in vitro. GMSC-Exo were extracted from the culture supernatant of GMSCs by ultracentrifugation. We found that GMSC-Exo attenuated the inflammatory response of PDLSCs induced by LPS. Furthermore, compared to treatment with LPS, treatment with GMSC-Exo attenuated the expression of NF-κB signaling and Wnt5a in LPS-induced PDLSCs. In conclusion, we confirmed that GMSC-Exo could suppress the inflammatory response of PDLSCs by regulating the expression of NF-κB signaling and Wnt5a, which paves the way for the establishment of a therapeutic approach for periodontitis.
Computational Screening of Single-Metal-Atom Embedded Graphene-Based Electrocatalysts Stabilized by Heteroatoms
Authors: Cho Ara , Park Byoung Joon , Han Jeong Woo
Published: April 2022

Metal-N-doped carbon is a promising replacement for non-precious-metal catalysts such as Pt for the oxygen reduction reaction (ORR) in polymer electrolyte membrane fuel cells (PEMFCs). Although these materials have relatively good catalytic activity and are cost-effective, they still have lower ORR activity than Pt, and so improving their performances is greatly required. In this study, high-throughput screening was employed based on density functional theory (DFT) calculations to search for good candidate catalysts with a transition metal atom coordinated by heteroatoms (B, N, S, O, and P) embedded in a graphene structure. In addition, coordinating a transition metal with two types of heteroatom dopants in a graphene structure was also considered. We calculated the binding energies of ORR intermediates on metal-heteroatom-based graphene structures because they are known to play a key role in ORR. Based on our results, the new group of electrocatalysts imparts excellent ORR activity for PEMFCs, and we suggest that our approach provides useful insight into exploring other promising candidate catalysts.
Comparability of Heart Rate Turbulence Methodology: 15 Intervals Suffice to Calculate Turbulence Slope – A Methodological Analysis Using PhysioNet Data of 1074 Patients
Authors: Blesius Valeria , Schölzel Christopher , Ernst Gernot , Dominik Andreas
Published: April 2022

Heart rate turbulence (HRT) is a characteristic heart rate pattern triggered by a ventricular premature contraction (VPC). It can be used to assess autonomic function and health risk for various conditions, e.g., coronary artery disease or cardiomyopathy. While comparability is essential for scientific analysis, especially for research focusing on clinical application, the methodology of HRT still varies widely in the literature. Particularly, the ECG measurement and parameter calculation of HRT differs, including the calculation of turbulence slope (TS). In this article, we focus on common variations in the number of intervals after the VPC that are used to calculate TS (#TSRR) posing two questions: 1) Does a change in #TSRR introduce noticeable changes in HRT parameter values and classification? and 2) Do larger values of turbulence timing (TT) enabled by a larger #TSRR still represent distinct HRT? We compiled a free-access data set of 1,080 annotated long-term ECGs provided by Physionet. HRT parameter values and risk classes were determined both with #TSRR 15 and 20. A standard local tachogram was created by averaging the tachograms of only the files with the best heart rate variability values. The shape of this standard VPC sequence was compared to all VPC sequences grouped by their TT value using dynamic time warping (DTW) in order to identify HRT shapes. When calculated with different #TSRR, our results show only a little difference between the number of files with enough valid VPC sequences to calculate HRT (<1%) and files with different risk classes (5 and 6% for HRT0-2 and HRTA-C, respectively). In the DTW analysis, the difference between averaged sequences with a specific TT and the standard sequence increased with increasing TT. Our analysis suggests that HRT occurs in the early intervals after the VPC and TS calculated from late intervals reflects common heart rate variability rather than a distinct response to the VPC. Even though the differences in classification are marginal, this can lead to problems in clinical application and scientific research. Therefore, we recommend uniformly using #TSRR 15 in HRT analysis.
Integrated Bioinformatics-Based Analysis of Hub Genes and the Mechanism of Immune Infiltration Associated With Acute Myocardial Infarction
Authors: Wu Yanze , Jiang Ting , Hua Jinghai , Xiong Zhiping , Chen Hui , Li Lei , Peng Jingtian , Xiong Wenjun
Published: April 2022

Background

Acute myocardial infarction (AMI) is a fatal disease that causes high morbidity and mortality. It has been reported that AMI is associated with immune cell infiltration. Now, we aimed to identify the potential diagnostic biomarkers of AMI and uncover the immune cell infiltration profile of AMI.

Methods

From the Gene Expression Omnibus (GEO) data set, three data sets (GSE48060, GSE60993, and GSE66360) were downloaded. Differentially expressed genes (DEGs) from AMI and healthy control samples were screened. Furthermore, DEGs were performed via gene ontology (GO) functional and kyoto encyclopedia of genes and genome (KEGG) pathway analyses. The Gene set enrichment analysis (GSEA) was used to analyze GO terms and KEGG pathways. Utilizing the Search Tool for Retrieval of Interacting Genes/Proteins (STRING) database, a protein–protein interaction (PPI) network was constructed, and the hub genes were identified. Then, the receiver operating characteristic (ROC) curves were constructed to analyze the diagnostic value of hub genes. And, the diagnostic value of hub genes was further validated in an independent data set GSE61144. Finally, CIBERSORT was used to represent the compositional patterns of the 22 types of immune cell fractions in AMI.

Results

A total of 71 DEGs were identified. These DEGs were mainly enriched in immune response and immune-related pathways. Toll-like receptor 2 (TLR2), interleukin-1B (IL1B), leukocyte immunoglobulin-like receptor subfamily B2 (LILRB2), Fc fragment of IgE receptor Ig (FCER1G), formyl peptide receptor 1 (FPR1), and matrix metalloproteinase 9 (MMP9) were identified as diagnostic markers with the value of p < 0.05. Also, the immune cell infiltration analysis indicated that TLR2, IL1B, LILRB2, FCER1G, FPR1, and MMP9 were correlated with neutrophils, monocytes, resting natural killer (NK) cells, gamma delta T cells, and CD4 memory resting T cells. The fractions of monocytes and neutrophils were significantly higher in AMI tissues than in control tissues.

Conclusion

TLR2, IL1B, LILRB2, FCER1G, FPR1, and MMP9 are involved in the process of AMI, which can be used as molecular biomarkers for the screening and diagnosis of AMI. In addition, the immune system plays a vital role in the occurrence and progression of AMI.
Estimating the Total Organic Carbon in Complex Lithology From Well Logs Based on Convolutional Neural Networks
Authors: He Yun , Zhang Zhanyang , Wang Xixin , Zhao Zhenyu , Qiao Wei
Published: April 2022

The total organic carbon content is an important indicator for evaluating source rocks. The lithology of the Majiagou Formation in the Tao 112 well area in the eastern Ordos Basin is complex and changeable. The source rock TOC is usually only 0.3%, and the logging response to the TOC is not obvious. The traditional method of TOC logging calculations using a linear relationship is not ideal. Convolutional neural networks can be used to help with these calculations, but they can only address non-linear problems. The major advantage of CNNs is that they can obtain optimal results through receptive fields and weight sharing with a limited number of samples. As such, this paper develops a novel non-linear TOC logging calculation model based on CNNs. The TOC content of the carbonate source rocks in the study area is calculated by logging calculations using both the multiple regression method and the CNN method. The experimental results show that the CNN method has higher accuracy in the calculation of TOC content in complex rock areas, and it can retain detailed TOC changes and reflect the changes of TOC more truly.
Cracking Modes and AE Precursors of Sandstone Failure Under Multi-Stage Uniaxial Compression
Authors: Zhu Xing , Wang Luqi , Yang Yang , Zhang Wengang , Zhang Peng
Published: April 2022

Denudation processes induced by external loading show scale-independent traits in rocks. Therefore, monitoring of micro-cracking features offers a possibility for assessing the structural health or rock massifs; eventually leading to early-warning systems capable of estimating the risk of catastrophic collapses. This study assesses the behaviour of acoustic emissions monitored while a sandstone sample was subjected to staged monotonic uniaxial compression. Particularly, waveform characteristics were recorded and analysed to identify the most predominant factors for classification. Then an unsupervised k-means algorithm was employed to cluster these parameters into two categories, related to the source being either a tensile or shear dislocation. Clusters showed noticeable differences, whilst results indicate that properties of AE waveforms vary significantly amongst diverse stages of loading, being the rise time the most sensitive parameter. Moreover, it seems that transitions amongst diverse behavioural stages of the sample are preceded by changes in the first lag of the autocorrelation function and the variance of the ratio of maximum amplitude and rise time of the ensemble of time histories observed within each stage. This trend is significantly more noticeable during the last stage, just before the collapse. This trait is in accord with the critical slowdown theory (CSD). This allows for the development of early-warning systems signalling partial collapse of rock masses.
Surgical Outcomes of Clival Chordoma Through Endoscopic Endonasal Approach: A Single-Center Experience
Authors: Chen Ge , Li Mingchu , Xu Wenlong , Wang Xu , Feng Ming , Wang Renzhi , Liu Xiaohai
Published: April 2022

Objective

Clival chordoma is a locally aggressive tumor with low metastatic potential. In the past decade, endoscopic endonasal approach (EEA) for clival chordoma has had a higher resection rate and a lower morbidity rate than transcranial approaches. Here, we present our initial single-center experience after EEA of clival chordomas.

Patients and methods

This study retrospectively analyzed 17 consecutive patients with clival chordoma who received EEA in our department between March 2015 and September 2021. The operation was performed by a single surgeon with EEA. The clinical and pathological characteristics were analyzed along with the surgical outcomes and complications.

Results

A total of 17 consecutive patients with clival chordoma received EEA with a median follow-up of 29.2 months (range 1-79). Gross total resection (GTR) was performed in 7 cases (41%), subtotal resection (STR) in 7 case (41%) and partially resection (PR) in 3 cases (18%). Cerebrospinal fluid leakage occurred in 2 cases (12%) and meningitis developed in 3 patients (18%) which were all successfully treated with intravenous antibiotics without any complications. There were no perioperative deaths or new focal neurological deficits postoperatively. Four in 7 patients with STR have had radiotherapy while the other three chose to be monitored. Till the last follow-up, three patients in STR group who received radiotherapy (3 in 4) had no tumor regrowth, while one in STR group with radiotherapy (1 in 4) showed tumor progression. Two patients in STR group without radiotherapy (2 in 3) showed stable tumor while the left one (1 in 3) showed tumor progression. One patient in the PR group died of tumor progression 2 years postoperation and the other one showed tumor progression and died of lung cancer 1 year postoperation. In addition, 1 in 7 patients with GTR had tumor recurrence in situ after 10 months and developed surgical pathway seeding in the spinal canal in C1 after 16 months. No recurrence occurred in the other 6 cases with GTR during the follow-up.

Conclusion

Although more cases are needed, our case series showed EEA is a safe and reliable method for clival chordoma with high resection rates and low morbidity rates. GTR without tumor residuum would improve the outcome.
Research on the Effect of Needle Eccentricity on the Jet Flow Characteristics
Authors: Jinwei Huang , Xinfeng Ge , Dongdong Chu , Jing Zhang , Bing Xu , Fei Gao , yuan Zheng
Published: April 2022

The position of the nozzle in the jet mechanism of the impulse turbine may cause an eccentric jet due to size processing and installation deviations. To study the effect of jet needle eccentricity on the jet, this article first analyzes the jet characteristics of the jet mechanism with different openings (20, 40, 60, 80, 100%) under 4.8% eccentricity, verify the reliability of the research method in this paper. Then the focus is on the jet characteristics of the jet mechanism at different eccentricities (0, 1, 2.1, 4.8, 8, and 14%) at 40% opening. The results show that as the eccentricity of the nozzle increases, the jet appears to be asymmetrical, and the shape of the jet at the inlet section of the runner gradually changes and becomes an irregular shape. The eccentricity of the water jet increases with the increase of the eccentricity of the needle; the efficiency of the injection mechanism gradually decreases, and the energy loss gradually increases. Before the eccentricity of 4.8%, the efficiency decreases more slowly, and after the eccentricity of 4.8%, the rate of efficiency decrease is accelerated.
Effect of Broadband Infrastructure on Rural Household CO2 Emissions in China: A Quasi-Natural Experiment of a “Broadband Village”
Authors: Rao Pan , Xie Fangting , Zhu Shubin , Ning Caiwang , Liu Xiaojing
Published: April 2022

This paper explores how broadband infrastructure affects rural household carbon dioxide emissions (HCE). Based on the Environmental Kuznets curve hypothesis, a quasi-natural experiment of a “Broadband Village” (B&V) in China is conducted. Panel data from 9,790 rural households were collected as part of the China Family Finance Survey (CHFS). The consumer lifestyle approach was used to calculate HCE and a Difference-in-Differences (DID) model was used to analyze the impact of a B and V pilot project on rural HCE. The results of DID model showed that B and V significantly increases rural HCE, with an influencing coefficient 1.7. Subsequently, Threshold Model was utilized to examine the nonlinear relationship between household broadband penetration and rural HCE. The results revealed the threshold effect between rural household broadband penetration and rural HCE. Namely, the growth effect of B and V to rural HCE would be much weaker, if rural household broadband penetration goes above a threshold level, 31.32%. Our analysis provides important insights for policymakers to formulate digital village and income redistribution policies to support rural carbon dioxide (CO2) emissions reductions.
Ageing Knowledge Structure in Global River Basins
Authors: Wei Yongping , Wu Shuanglei , Lu Zhixiang , Wang Xuemei , Wu Xutong , Xu Li , Sivapalan Murugesu
Published: April 2022

Understanding the historical evolution of science development for rethinking science in the Anthropocene is crucial for our future survival. This paper analyzed the knowledge development of the top 95 most researched river basins in the Web of Science database in the past 3 decades (1987–2017) using a network metric-based framework, comprising one scalar metric and three structural metrics: equality, efficiency, and resilience. We found that the highly researched river basins accounting about 30% of total publications, including the Yangtze River and the Great Lakes, demonstrated the “ageing” knowledge structures characterized by high inequality, low efficiency, and large redundancy with continuous expansion in scales. Dominations of knowledge interactions among Environmental Sciences, Water Resources, Marine Science and Freshwater Biology contributed to this knowledge structure. Transformations of both the composition and structure of the knowledge system is required to support global river basin management in the Anthropocene.
Characterization and Risk Assessment of Airborne Polycyclic Aromatic Hydrocarbons From Open Burning of Municipal Solid Waste
Authors: Cheng Ke , Li Jing-Yu , Wang Yan , Ji Wan-Wan , Cao Yi
Published: April 2022

In order to reveal the pollution characteristics and risk level of polycyclic aromatic hydrocarbons (PAHs) exposed to air from open burning in China, PM2.5 samples were collected from the open burning of different types of municipal solid waste (MSW). The component of MSW differed from plastics, paper, wood and bamboo, and mixed garbage. A flue gas dilution sampling system was employed to simulate open burning testing on MSW samples from different functional urban areas. Emission characteristics and health risk assessments of PAHs in PM2.5 were analyzed. The results showed that the 16 PAHs were detected ranged from 16.0 to 10,386.9 ngm−3. The total PAH concentration of wood and bamboo wastes was the highest (24,512.1 ngm−3), while that in plastics was the lowest (4,084.7 ngm−3). Speciation composition of PAHs in PM2.5 with high-molecular-weight PAHs was dominant compared to low-molecular-weight PAHs. Health risk assessment showed that the proportion of samples with the lifelong lung carcinogenic risk value greater than 10–6 was 68.7% of the totals, most of the PAHs in PM2.5 had a certain risk of cancer. The speciation of Bap posed the greatest health risks to adults and children. The carcinogenic sequence of four components of wastes was as follows: wood and bamboo > mixed garbage > paper > plastics and the risk for adults was about 2.26 times higher than for children. Totally, the PAHs speciation of BaP, DBahA, BbF, IcdP, BaA, BkF, and Chr in PM2.5 from the open burning of MSW can bring high carcinogenic risk to human health by respiratory exposure, and the risk value of adults is higher than that of children. The findings show the different conclusion with the results of related researches on the environmental effect of waste incineration power plants or incinerators. Therein, it can provide supplementary data to evaluate the impact of open burning of MSW on ambient air quality.
Comparing Remote Sensing and Field-Based Approaches to Estimate Ladder Fuels and Predict Wildfire Burn Severity
Authors: Forbes Brieanne , Reilly Sean , Clark Matthew , Ferrell Ryan , Kelly Allison , Krause Paris , Matley Corbin , O’Neil Michael , Villasenor Michelle , Disney Mathias , Wilkes Phil , Bentley Lisa Patrick
Published: April 2022

While fire is an important ecological process, wildfire size and severity have increased as a result of climate change, historical fire suppression, and lack of adequate fuels management. Ladder fuels, which bridge the gap between the surface and canopy leading to more severe canopy fires, can inform management to reduce wildfire risk. Here, we compared remote sensing and field-based approaches to estimate ladder fuel density. We also determined if densities from different approaches could predict wildfire burn severity (Landsat-based Relativized delta Normalized Burn Ratio; RdNBR). Ladder fuel densities at 1-m strata and 4-m bins (1–4 m and 1–8 m) were collected remotely using a terrestrial laser scanner (TLS), a handheld-mobile laser scanner (HMLS), an unoccupied aerial system (UAS) with a multispectral camera and Structure from Motion (SfM) processing (UAS-SfM), and an airborne laser scanner (ALS) in 35 plots in oak woodlands in Sonoma County, California, United States prior to natural wildfires. Ladder fuels were also measured in the same plots using a photo banner. Linear relationships among ladder fuel densities estimated at broad strata (1–4 m, 1–8 m) were evaluated using Pearson’s correlation (r). From 1 to 4 m, most densities were significantly correlated across approaches. From 1 to 8 m, TLS densities were significantly correlated with HMLS, UAS-SfM and ALS densities and UAS-SfM and HMLS densities were moderately correlated with ALS densities. Including field-measured plot-level canopy base height (CBH) improved most correlations at medium and high CBH, especially those including UAS-SfM data. The most significant generalized linear model to predict RdNBR included interactions between CBH and ladder fuel densities at specific 1-m stratum collected using TLS, ALS, and HMLS approaches (R2 = 0.67, 0.66, and 0.44, respectively). Results imply that remote sensing approaches for ladder fuel density can be used interchangeably in oak woodlands, except UAS-SfM combined with the photo banner. Additionally, TLS, HMLS and ALS approaches can be used with CBH from 1 to 8 m to predict RdNBR. Future work should investigate how ladder fuel densities using our techniques can be validated with destructive sampling and incorporated into predictive models of wildfire severity and fire behavior at varying spatial scales.
Seamless Gene Correction in the Human Cystic Fibrosis Transmembrane Conductance Regulator Locus by Vector Replacement and Vector Insertion Events
Authors: Suzuki Shingo , Chosa Keisuke , Barillà Cristina , Yao Michael , Zuffardi Orsetta , Kai Hirofumi , Shuto Tsuyoshi , Suico Mary Ann , Kan Yuet W. , Sargent R. Geoffrey , Gruenert Dieter C.
Published: April 2022

Background: Gene correction via homology directed repair (HDR) in patient-derived induced pluripotent stem (iPS) cells for regenerative medicine are becoming a more realistic approach to develop personalized and mutation-specific therapeutic strategies due to current developments in gene editing and iPSC technology. Cystic fibrosis (CF) is the most common inherited disease in the Caucasian population, caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. Since CF causes significant multi-organ damage and with over 2,000 reported CFTR mutations, CF patients could be one prominent population benefiting from gene and cell therapies. When considering gene-editing techniques for clinical applications, seamless gene corrections of the responsible mutations, restoring native “wildtype” DNA sequence without remnants of drug selectable markers or unwanted DNA sequence changes, would be the most desirable approach.

Result: The studies reported here describe the seamless correction of the W1282X CFTR mutation using CRISPR/Cas9 nickases (Cas9n) in iPS cells derived from a CF patient homozygous for the W1282X Class I CFTR mutation. In addition to the expected HDR vector replacement product, we discovered another class of HDR products resulting from vector insertion events that created partial duplications of the CFTR exon 23 region. These vector insertion events were removed via intrachromosomal homologous recombination (IHR) enhanced by double nicking with CRISPR/Cas9n which resulted in the seamless correction of CFTR exon 23 in CF-iPS cells.

Conclusion: We show here the removal of the drug resistance cassette and generation of seamless gene corrected cell lines by two independent processes: by treatment with the PiggyBac (PB) transposase in vector replacements or by IHR between the tandemly duplicated CFTR gene sequences.
The Role of NcRNAs to Regulate Immune Checkpoints in Cancer
Authors: Jiang Yicun , Zhao Leilei , Wu Yiwen , Deng Sijun , Cao Pu , Lei Xiaoyong , Yang Xiaoyan
Published: April 2022

At present, the incidence of cancer is becoming more and more common, but its treatment has always been a problem. Although a small number of cancers can be treated, the recurrence rates are generally high and cannot be completely cured. At present, conventional cancer therapies mainly include chemotherapy and radiotherapy, which are the first-line therapies for most cancer patients, but there are palliatives. Approaches to cancer treatment are not as fast as cancer development. The current cancer treatments have not been effective in stopping the development of cancer, and cancer treatment needs to be imported into new strategies. Non-coding RNAs (ncRNAs) is a hot research topic at present. NcRNAs, which include microRNAs (miRNAs), circular RNAs (circRNAs), and long non-coding RNAs (lncRNAs), participate in all aspects of cancer biology. They are involved in the progression of tumors into a new form, including B-cell lymphoma, glioma, or the parenchymal tumors such as gastric cancer and colon cancer, among others. NcRNAs target various immune checkpoints to affect tumor proliferation, differentiation, and development. This might represent a new strategy for cancer treatment.
Chromosome-Scale Assembly and Characterization of the Albino Northern Snakehead, Channa argus var. (Teleostei: Channidae) Genome
Authors: Zhou Chaowei , Li Yan , Zhou Yan , Zou Yu , Yuan Dengyue , Deng Xingxing , Lei Luo , Su Jian , Zhu Chengke , Ye Hua , Luo Hui , Lv Guangjun , Zhou Xinghua , Kuang Gangqiao , Zhang Chuang , Wu Jun , Zheng Zonglin , Xiao Shijun , Li Minghui
Published: April 2022

Northern snakehead, Channa argus (C. argus), is an important economic and ecological fish species. The wild population of the species was sharply declined in the last decade. A high-quality reference genome could lay a solid foundation for the genetic and conservation studies for C. argus. In this work, we report a chromosomal genome assembly with PacBio and Hi-C technology using the albino northern snakehead, a color variety of C. argus. A 644.1-Mb genome with 24 chromosomes was obtained with a contig and scaffold N50 of 11.78 and 27.8 Mb, respectively. We inferred that C. argus diverged from A. testudineus around 85.6 million years ago. 514 expanded gene families and 214 positively selected genes were identified in the C. argus genome. The chromosome-level genome provides a valuable high-quality genomic resource for population, as well as genetic and evolutionary studies for C. argus and other species in Channidae.
Thickness Distributions of Mold Flux Film and Air Gap in Billet Ultra-High Speed Continuous Casting Mold Through Multiphysics Modeling
Authors: Xu Pei , Wang Sijie , Zhou Yongzhi , Chen Dengfu , Long Mujun , Duan Huamei
Published: April 2022

The thicknesses of mold flux film and air gap are significant factors that affect the high-efficiency heat transfer, the strand lubrication and mold taper design of billet ultra-high speed continuous casting mold. Therefore, this paper established the three-dimensional fluid flow, heat transfer and solidification model, interfacial heat transfer model and two-dimensional stress-strain model to conduct multiphysics modeling. Thereby the thickness distributions of liquid slag, solid slag and air gap in the ultra-high speed billet continuous casting mold were obtained, and analyzing the effects of melting temperature of mold flux and mold taper. The results indicate that the thicknesses of liquid slag and solid slag increase and decrease respectively along the casting direction, and air gap mainly concentrates near the mold corner. The maximum thicknesses of liquid slag, air gap, and solid slag at the mold outlet are respectively 0.18 mm at the center of the strand surface (x = 0 mm), 0.28 mm at the strand corner (x = 80 mm) and 0.67 mm at x = 74 mm. The lower melting temperature of mold flux, the greater the liquid slag thicknesses and ascend from 0.14 to 0.18 mm, and conversely the maximum air gap thicknesses descend from 0.31 to 0.28 mm and existing ranges also get smaller, which is more favorable for the strand lubrication. To eliminate the air gap, the appropriate linear mold taper is 0.45% m−1 at the 6.5 m/min in casting speed.
Research Progress of Gallium Nitride Microdisk Cavity Laser
Authors: Zhu Gangyi , Qin Feifei , Li Xin , Sun Yang , Gao Fei , Tian Mufei , Ji Baojian , Wang Yongjin
Published: April 2022

Whispering gallery mode (WGM) cavities provide resonance configurations for light propagation through internal reflection, achieving high Q factors, low thresholds, and small mode volumes. GaN-based materials exhibit high freedom in band engineering and are highly compatible with contemporary semiconductor processing technology. Recently, lasers from artificial GaN microdisks, obtained by combining the excellent material properties of GaN with the advantages of WGM, have attracted considerable research attention. These have a wide application scope in optical communication, display, and optoelectronic integration. In this review, we summarize the recent advances in GaN-based WGM microlasers, including the fabrication methods for GaN microcavities, observations of optical pumped GaN microdisk lasing, lasing mechanisms, comparison of Q factors, lasing modes, and threshold properties, commonly used light field control techniques, and mode clipping methods. Furthermore, we introduce the recent advances in electrically driven GaN-based laser diodes, followed by research challenges and strategies for promising applications, such as electrically pumped lasers and optoelectronic chip integration.