bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on axial-flow hydrocyclone for in-situ sand removal of natural gas hydrate in the subsea
Authors: Lin Haitao , Huang Yuan , Wang Hualin
Published: March 2021

Natural gas hydrate (NGH) has become the most potential emerging green energy known in the 21st century due to its characteristics of wide distribution, abundant reserves and clean combustion. This study designs an axial annulus in situ hydrocyclone desander (AAIHD) based on drilling instruments in order to resolve the serious problem of sand production during solid fluidization of NGH. The effect of the inlet flow rate and separation zone length on the sand removal efficiency of the AAIHD is tested through experimental research. The results indicate that AAIHD has a higher separation performance when the separation zone length is L/D=12.4 and the inlet flow rate is in the range of 10 m3/h to 25 m3/h, and the maximum separation efficiency reaches 77.4%. The purpose of this study is to achieve in-situ sand removal and the backfilling of sand slurry in addition to facilitate the advancement of solid fluidized exploration technologies.
Integrated energy system planning study based on load prediction
Authors: Yang Jialin , Li Zhen , Wang Nan , Zhao Pengxiang , Zhou Xichao , Cong Lin , Xue Lu , Wang Yongli
Published: March 2021

The planning of integrated energy system is a very complex multi-objective, multi-constraint, nonlinear, random uncertain hybrid combination optimization problem, its planning and design process should consider not only the system capacity, energy exchange, energy storage, energy and other links between the interdependence, but also the interaction and mixing of cold, hot, electricity and other multi-energy flow, which is essentially a non-deterministic polynomial problem. Based on load prediction technology, combined with scene generation, multi-interconnected energy system modeling and other technologies, around the integrated energy system planning and design, consider the comprehensive evaluation of the whole life cycle, an optimal configuration of the integrated energy system is formed.
Research on Post Investment Evaluation of Distribution Network Infrastructure Project Adapting to Transmission and Distribution Price Reform
Authors: Zeng Linjun , Zeng Yan , Wang Dan , Chen Pan , Hong Xin , Huang Juan , Su Hongwei
Published: March 2021

Under the background of the continuous promotion of the current transmission and distribution price reform, the company's investment strategy is constantly inclined to the distribution network, so it is more important to evaluate the implementation process and effect of its investment. Therefore, on the basis of the current distribution network post evaluation work, it is urgent to adjust the project investment post evaluation index system adaptively, and strengthen its application in investment management, so as to give play to its greater value in the company's investment lean management. For this reason, combined with the requirements of the current transmission and distribution price reform, this paper puts forward two suggestions for the current post evaluation work: first, to adapt to the transmission and distribution price reform, it is suggested to optimize the existing indicators and improve the adaptability of post evaluation work; second, it is suggested to strengthen the application of post evaluation results. Through the optimization of the above two points, the closed-loop investment management of distribution network project is formed, and the efficiency of investment management is improved.
Suitability evaluation of underground space development in Dalian
Authors: Mengmeng Gao , Nan Yang , Yi Wang , Xiaolei Li , Qiong Liu , Jinhui Wu , Zixin Zhao
Published: March 2021

Rational development and utilization of urban underground space has become an important measure to alleviate the contradiction between supply and demand of land resources, improve urban capacity and optimize urban layout. Underground space is an important part of the geological environment because of its natural resources. Unreasonable development will lead to geological environment problems. In this paper, combined with the actual situation of Dalian City, on the basis of comprehensive analysis of geological environment conditions, eight indicators are selected from the aspects of topography, engineering geological conditions, hydrogeological conditions, geological hazards, ecological factors and human activities to construct the hierarchy model of suitability evaluation for underground space development in Dalian City. The analytic hierarchy process and comprehensive index method are applied to the evaluation. The results show that: the suitable area, secondary suitable area, less suitable area and unsuitable area are 3812.58km2, 5430.91km2, 2711.38km2 and 1659.06km2, accounting for 28.00%, 39.89%, 19.92% and 12.19% respectively. The evaluation results can provide the basis for the future development and utilization planning of underground space in Dalian city.
Almost half of the Pb content leaving in the bottom of the sea
Authors: Yang Dongfang , Tian Minging , Ling Weifeng , Wang Qi , Li Haixia
Published: March 2021

Using survey data of Pb in water body from southwest of Jiaozhou Bay to west of bay mouth, in August 1992 and according to the horizontal change model and the vertical change model of matter content put forward by authors, we calculate the horizontal loss amount, vertical diluted amount and vertical sediment amount of Pb in surface and bottom layer and determine the model diagram of Pb content horizontal and vertical changes. The results showed that in August, the absolutely horizontal loss amount of Pb content in surface layer and bottom layer was 8.92μg/L, and the relatively horizontal loss amount of Pb content was 56.10%. The absolutely horizontal increase amount of Pb was 5.74μg/L in bottom layer, and the relatively horizontal increase amount was 42.23%. In the southwestern waters of the bay, the absolutely vertical diluted amount of Pb was 8.05μg/L in both surface and bottom layer, and the relatively vertical diluted amount was 50.62%. Meanwhile, in the western waters of bay mouth, Pb content in the surface and bottom layer had an absolutely vertical sediment amount of 6.61μg/L and a relatively vertical sediment amount of 48.63%. From the southwestern waters of the bay to the western waters of the bay mouth, a large amount of Pb content in the surface layer is deposited on the seabed. Therefore, during the horizontal migration of Pb content on the surface, the loss was nearly 60.00% when the current left the bay. However, Pb content in the bottom layer increased by 42.23% during its horizontal migration. Thus, the high Pb content in the surface layer is retained at the bottom of Jiaozhou Bay. When the current left the inside of the bay, Pb content in the surface layer was relatively high with the vertical diluted amount of Pb content in the surface layer and bottom layer reaching almost 50%. When the main sea current reached the western part of the bay mouth, the Pb content in the surface layer could settle on the seabed rapidly and continuously with a high sediment amount of 48.63%.
Research on Pump Inspection Cycle Early Warning Method Based on Big Data
Authors: Lihong Du , Yufang Liu , Fei Cao , Fang Li , Guizhi Min , Zhongbo Liu , Zhixue Xia , Zhanmin Zhang
Published: March 2021

At present, the existing indicator diagram can only be used for expost judgment and can not give early warning, and the influencing factors of pump inspection period are nonlinear, multi constrained and multi variable. In this paper, big data machine learning method is used to carry out relevant research. Firstly, around the influencing factors of pump inspection cycle, relevant data are collected and the evaluation index of pump inspection cycle is designed. Then, based on feature engineering technology, the production parameters of oil wells in different pump inspection periods are calculated to form the analysis sample set of pump inspection period. Finally, the early warning model of pump inspection period is established by using machine learning technology. The experimental results show that: the pump inspection cycle early warning model established by stochastic forest algorithm can identify the pump inspection status of single well, and the accuracy rate is about 85%.
Study on the Effects of Different Vegetation Restoration Model son Soil Remediation
Authors: Dong Yijie , Luo Yuanyuan , Li Jinbiao , Deng Shanqiao , Zheng Zhiyang
Published: March 2021

In order to improve the restoration effect of soils in mining wasteland, based on site investigations for the mining wasteland, five different vegetation restoration models are used for soil restoration, and study on effect mechanism of different vegetation restoration models on physical and chemical properties as well as activity of enzyme in soil are conducted, providing a solid theoretical basis for guiding the subsequent management of the soil in the mining area.
Experimental Study on the Optimization of a Diversion Engineering in Lower Reaches of Fuhe River
Authors: Wang Zhichao , Xu Xinfa , Huang Zhiwen , You Wensun
Published: March 2021

In jiangxi province, china, a new river will be excavated in the southern part of Qinglan Lake to drainage the main flow of Fuhe River into the Lake to improve the local flood prevention and navigation problems. A physic model is established to analyze the changes of flow characteristics under different engineering schemes. The research shows that water level decreases 1.91m, flow velocity of the upstream increases to 4.83 m/s, under P=5% River flood, which means the diversion engineering can significantly relieve the local flood pressure, but increase the scouring risks of wading buildings such as piers and embankments. Then the further optimization study shows that scheme 3 not only reduced the engineering quantity, but also decreased velocity increase rate from 61% to 48%.
Optimal base point selection method based on convex hull construction technology
Authors: Dong Jian , Zhang Zhiqiang , Tang Lulu , Peng Rencan , Ji Hongchao
Published: March 2021

The primary purpose of maritime delimitation is to ensure the maximum internal waters area obtained. In order to grantee the maximum internal waters area obtained with the selected base point, the idea and method of optimal selection of the territorial sea base points with the convex hull (minimum convex hull) construction technology is proposed. The ideal base points are selected by constructing convex hull for all alternative base points, which makes it possible to realize the automatic selection of base points under the principle of the maximum internal waters area.
Degradation of Organic Pollutants by Titanium Dioxide Matrix Composites
Authors: Han Li , Gao Yan , Gao Xing , Gong Weijuan , Wang Hui
Published: March 2021

As a semiconductor material, titanium dioxide has the advantages of stable chemical properties, no pollution and low price, which is widely used in the field of organic pollutant degradation. The modification methods of semiconductor composite and nonmetallic doping for titanium dioxide are described. The degradation efficiency of modified titanium dioxide composite for organic pollutants is proposed. The advantages and disadvantages of the composite in preparation and application are pointed out. Finally, the development direction of modified titanium dioxide composite in the future is described.
The research on the transition of green agriculture to the industrialization path of supply-side reform
Authors: Su Dan
Published: March 2021

Under the background of the steady progress of the structural reform of the agricultural supply side, the rural ecological agriculture in the transition stage is faced with a series of bottlenecks and problems such as the lag of production technology renewal, the single management mechanism and the aggravation of environmental degradation. It is difficult to effectively form a new form of green, coordinated and sustainable development. Therefore, we should make full use of the favorable conditions such as policy support and institutional guarantee given by the structural reform of the agricultural supply side, and introduce efficient and innovative production and management models around the industrial upgrading, so as to promote the low-carbon, intensive and diversified transformation of the existing ecological agriculture operation system.
Climate Change Litigation in China: Barriers and Pathways
Authors: Wu Si cheng
Published: March 2021

China has been known for its government-oriented method in tackling climate issues, yet the role played by Chinese judiciary in its national response to climate change remains obscure. This article fills the gaps by focusing on the following sub-questions:1) what are the legal barriers and favorable preconditions for the emergence of CCL in China?; 2) if CCL were to occur, what would be the most likely pathway ? An analysis of Chinese legal preconditions reveals that, while some normative and institutional barriers stand in the way, some preconditions have already been satisfied or in the process of preparing. Having compared the preparation of legal preconditions for possible patterns of Chinese CCLs and the motivation of potential plaintiffs, the article concludes that the most likely pattern for Chinese future CCL would be civil actions brought by the NGOs holding the polluters accountable for causing damages to the climate related public interests.
Design and control of precision work stage with air bearing for large size optical grating fabrication
Authors: Sirige
Published: March 2021

Scanning Beam Interference Lithography (SBIL) is an advanced large-diameter and high-precision plane grating manufacturing solution, which has very high requirements for the positioning accuracy and running speed of the work stage carrying the substrate. In order to improve the size and accuracy of optical grating manufacturing in scanning interference lithography further, air bearing with high precision, high loading capacity and high stiffness is one of the key components for the work stage. In this paper, in order to design a large stroke work stage which meets the demand, firstly, the air bearing, the core part of the work stage, is analyzed and calculated by finite element method, and the pressure distribution curve of the air bearing of the work stage is obtained. On this basis, the linear air bearing with high bearing capacity and high stiffness is designed by using the omni-directional preloading analysis method of high-precision motion platform. Based on the high-precision position feedback of grating encoder, the high-precision closed-loop control of 20nm (3σ) is realized by using PID control and trap filter, which meets the design and requirements, and provides technical and engineering support for the manufacture of large-scale optical grating.
Effects of exogenous addition of cadmium on cadmium speciation in hyperaccumulator of Sedum alfredii Hance
Authors: Yang Jiawei , Sun Lin , Shen Xing , Peng Changsheng
Published: March 2021

Continuous chemical extraction is considered to be one of the most common methods for the extraction of heavy metals speciations in plants. However, the basis for the extraction order of this method is not explained and has been rarely studied. In this paper, we analyzed the speciations of cadmium in plants by a four-step continuous extraction method. The extraction sequence of ethanol and water was studied to study the effect of extraction sequence on the extraction rate of extraction agent. The results showed that cadmium exists mostly in NaCl extraction state and the extraction rate of the two kinds of extraction agents decreased when the order of ethanol and water was changed.
Synthesis parameter optimization for uniform and stable perovskite quantum dots
Authors: Huang Dong , Zheng Ronghong , Li Qinyi , Luo Chengzhao , Chen Yu
Published: March 2021

Colloidal lead halide perovskites nanocrystals, also known as quantum dots, have been intensively studied as promising optoelectronic materials and have attracted widespread attention due to their unique optical versatility, high photoluminescence quantum yield and convenient synthesis. Among them, the potential of all-inorganic halide caesium lead perovskite (CsPbX3, X = Cl, Br, I) is particularly prominent. In this work, by adjusting the experimental parameters, including precursor preservation condition, reaction temperature and the isolation/purification process, CsPbBr3 quantum dots with uniform size, neat arrangement, narrow full width at half maxima and excellent luminescent properties have been successfully prepared, which lays a good foundation for its potential application in practical optoelectronic devices.
Regulation of hole transport layer for perovskite quantum dot light-emitting diodes
Authors: Zheng Ronghong , Huang Dong , Shen Dongyang , Luo Chengzhao , Chen Yu
Published: March 2021

Perovskite quantum dots have been widely used in light-emitting diodes (LEDs) because of their adjustable color, high quantum yield and easy solution processing. Furthermore, matching energy levels of device plays a profound role in the resultant LEDs. In this study, a polymeric material, namely poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4’-(N-(pbutylphenyl))diphenylamine)] (TFB), is introduced between the quantum dot emission layer and the hole injection layer PEDOT:PSS, which not only prevents the fluorescence quenching caused by the direct contact between the perovskite layer and the hole injection layer, but also reduces hole injection barrier, both being beneficial to the device performance. The optimal thickness of TFB has been obtained by adjusting the rotational speed and precursor solution concentration during spin coating. The optimized quantum dots LED has a switching on voltage of about 2.2 V, a maximum brightness of 4300 cd/m2, a maximum external quantum efficiency of 0.15%, and a maximum current density of 0.54 cd/A.
Effects of different factors on adventitious bud induction from stem explants of Ludisia discolor
Authors: Liu Ying , Li Xiaohao , Chen Jingye , Xue Yingbin , Zhu Yinling
Published: March 2021

In this study, the stem explants of Ludisia discolor were used as experimental materials to investigate the effects of 6-BA, NAA, Cu2+ and Ag+ on the induction of adventitious bud regeneration, and to analyze the most suitable culture conditions for stem explants regeneration. The results showed that when the medium was supplemented with 1.0 mg/L 6-BA, 0.75 mg/L NAA, 0.25 mg/L CuSO4, or 6.4 mg/L AgCl, the best regeneration effects would be gained, respectively. And the adventitious bud regeneration rate reached the maximum, which were 61.67%, 83.67%, 80.95% and 87.63%, respectively. The results of this study provided a theoretical basis for tissue culture and rapid propagation of L. discolor.
Research on the business model innovation applicable to intelligent bucket in medical and chemical industry
Authors: Feng Liu , Feifei Chen , Yichen Jiang , Yichen Chang , Mei Lan , Jia’ni Chen , Zhiqi Jin , Ningbo Wang , Jie Yang
Published: March 2021

As an important category of urban waste, medical waste has the characteristics of polluting the environment, spreading diseases, and threatening health. It is directly related to the health of the people. The treatment of medical waste is an important part of epidemic prevention and control, and it is also a line of public health defense. This article proposes a business model that combines “C2M + multi-channel marketing” and “Internet of Things + medical” trash cans. Through market analysis, it analyzes the market situation of medical waste pretreatment link in China-medical trash can. Through the 4P marketing theory, a medical trash can be based on the Internet, which is designed mainly from the product perspective and the C2M production model is adopted; from the channel perspective, the product is first tested and sold through multiple channels.

This article aims to implement the “Medical Waste Management Regulations” for the medical trash can industry and open the market to provide new ideas for reform and innovation.
What Lies in between Telomere and Organismal Ageing: Comparison between Replicative Senescence and Stress-Induced Premature Senescence
Authors: Jia Hanyi
Published: March 2021

A mitotic cell that rests in permanent cell cycle arrest without the ability to divide is considered as a senescent cell. Cellular senescence is essential to limit the function of cells with heavy DNA damages. The lack of senescence is in favour of tumorigenesis, whereas the accumulation of senescent cells in tissues is likely to induce ageing and age-related pathologies on the organismal level. Understanding of cellular senescence is thus critical to both cancer and ageing studies.

Senescence, essentially permanent cell cycle arrest, is one of the results of DNA damage response, such as the ataxia telangiectasia mutated and the ataxia telangiectasia and Rad3-related signaling pathways. In other cases, mild DNA damages can usually be repaired after DNA damage response, while the cells with heavy damages on DNA end in apoptosis. The damage to the special structure of telomere, however, prone to result in permanent cell cycle arrest after activation of DNA damage response. In fact, a few previous pieces of research on ageing have largely focused on telomere and considered it a primary contributor to different types of senescence. For instance, its reduction in length after each replication turns on a timer for replicative senescence, and its tandem repeats specific to binding proteins makes it susceptible to DNA damage from oxidative stress, and thus stress-induced premature senescence. In most of the senescent cells, the accumulation of biomarkers is found around the telomere which has either its tail structure disassembled or damage foci exposed on the tandem repeats.

In this review, among several types of senescence, I will investigate two of the most common and widely discussed types in eukaryotic cells -replicative senescence and stress-induced premature senescence - in terms of their mechanism, relationship with telomere, and implication to organismal ageing.
Applications of chiral spirocyclic phosphoric acid in the synthesis of natural products
Authors: Yang Fan
Published: March 2021

With a 10 years development, chiral spirocyclic phosphoric acids (SPAs) have attracted a substantial amount of attention from the synthetic organic chemistry community. This kind of small molecule organic catalysts has some advantages like easy to obtain, no transition metal and wide application range. Because of avoiding the use of toxic substances which are limited in the process of drug synthesis, a large number of studies pay attention to the key structures (such as indole, carbozole.) containing pharmacological active components in natural products. And most of them get a excellent result in yields (more than 80% yield) and enantioselectivities (more than 90% ee). These studies can provide new pathways to nature products.
Study on safety evaluation of hazardous chemicals transportation industry in Capital city based on principal component analysis and cluster analysis
Authors: Lv Zekai , Lv Shuran
Published: March 2021

With the reform of chemical transportation industry accelerating, the safety evaluation of chemical transportation industry in China is becoming more and more standardized. Based on the theory of big data analysis and SPSS software as a platform, first of all, of the Beijing 91 the system construction and management of dangerous chemicals transportation enterprises, safety culture, safety production standardization 24 safety evaluation indexes such as principal component analysis, it is concluded that safety training basic requirements, loading and unloading operation, parking lot, civil air defense, vehicle dynamic supervision, system construction and management, safety production standardization, pilot eight kinds of factors as the main indexes for safety assessment. After using the eight indexes of 91 clustering analysis for transport enterprises, the enterprise is divided into five clusters of reasonable results, through the summary of common characteristics within the same cluster enterprises, it is concluded that the handling operation index plays an important role in classification for transport enterprises such as conclusion, can provide reference for other areas. At the same time, the conclusion can be used as a reference for the follow-up safety evaluation of hazardous chemical transportation enterprises, so as to achieve the purpose of targeted safety inspection.
Research on the index system of chemical enterprise safety risk state based on analytic hierarchy
Authors: Wu Fei , Cheng Ling , Yu Yinglei , Sun Jiajia
Published: March 2021

Based on the 19 selected representative chemical enterprises in jiangsu province, we investigate the safety risk situation of chemical enterprises from the aspects of personnel technical level, equipment failure, major hazard sources, production process, environment, accident, certification, safety assessment and emergency response capacity. We found the following problems: the most part of staffs education is below undergraduate course; have major hidden dangers at district/county level and above; the vast majority of enterprises of dangerous chemicals maximum action/reaction temperature over dangerous chemicals flash point, etc. The index system of chemical enterprise safety risk state is constructed from six aspects: personnel, equipment, material, method, environment and safety management. The key index system of security risk state warning is put forward from the aspects of personnel, equipment, method, environment and safety management. We use the analytic hierarchy process (AHP) method to determine the chemical enterprise safety risk status indicators weight, and finally determine the state of the chemical enterprise safety risk classification standard.
Inhibition of MDA-MB-231 cell proliferation by pHLIP(Var7)-P1AP and SPECT imaging of MDA-MB-231 breast cancer-bearing nude mice using 125I-pHLIP(Var7)-P1AP
Authors: Chen Yue Hua , Yu Ming Ming , Wang Zhen Guang
Published: March 2021

Aim To observe the effect of pHLIP(Var7)-P1AP on the proliferation of MDA-MB-231 triple-negative breast cancer cells and the small-animal single-photon-emission computed tomography (SPECT) imaging of breast cancer–bearing mice carrying MDA-MB-231 cells.

Methods Peptide pHLIP(Var7)-P1AP was synthesized by solid-phase peptide synthesis. The binding of fluorescently labeled pHLIP(Var7)-P1AP to MDA-MB-231 cells under various pH conditions and its effect on MDA-MB-231 cell proliferation were analyzed. pHLIP(Var7)-P1AP was labeled with 125I, and the biological distribution of 125I-pHLIP(Var7)-P1AP in the breast cancer mouse model carrying MDA-MB-231 cells as well as the outcome of small-animal SPECT imaging were evaluated.

Results pHLIP(Var7)-P1AP was successfully synthesized. Under pH 6.0, fluorescently labeled pHLIP(Var7)-P1AP had a higher binding ability to MDA-MB-231 cells and significantly inhibited the proliferation of MDA-MB-231 cells. The labeling efficiency of pHLIP(Var7)-P1AP with 125I was 33.1 ± 2.7 %, and the radiochemical purity was 98.5 ± 1.8 %. 125I-pHLIP(Var7)-P1AP showed a high concentration in tumors. Small-animal SPECT imaging showed clearly visible tumors at 4 h after injection.

Conclusions In the acidic environment, pHLIP(Var7)-P1AP can efficiently target MDA-MB-231 cells and inhibit their growth. Small-animal SPECT of 125I-pHLIP(Var7)-P1AP can clearly image tumors.
Famotidine Repurposing for Novel Corona Virus Disease of 2019: A
Systematic Review
Authors: Chenchula Santenna , Ray Avik , Sadasivam Balakrishnan
Published: March 2021

Background COVID-19 caused by SARS-CoV-2 was declared as a global
pandemic by the WHO. Famotidine is a histamine-2 (H2) receptor antagonist
which blocks the H2 receptors in the parietal cells, decreasing gastric acid
secretion. Our review aims to study all the available scientific evidence on
famotidine research outcomes systematically to introspect its clinical
efficacy and probable mechanisms and clinical efficacy against
SARS-CoV-2.

Methodology An electronic search of PubMed, Scopus and Google Scholar
was performed using MeSH terms “SARS CoV-2” OR
“COVID-19” AND“FAMOTIDINE”. Relevant
informationwas extracted from studies reporting the efficacy of famotidine
in COVID-19.

Results We found a total of 32 studies, out of which only 14 were
relevant and were included in our review.Molecular computational studies
showed that famotidine selectively acts on viral replication proteases
papain-like protease (PLpro) and 3-chymotrypsin-like protease (3CLpro).
Additionally, it acts via inverse-agonism on the H2 receptors present in
neutrophils and eosinophils which leads to inhibition of cytokine release.
Clinical study findings have pointed toward significant improvements in
COVID-19 patient-reported symptoms in non-hospitalized patients and
reduction in intubation or death in critically ill patients associated with
the usage of famotidine. However,in one of the studies,famotidine has failed
to show any significant benefit in reducing mortality due to COVID-19.

Conclusion Famotidine has the potential to answer the ongoing global
challenge owing to its selective action on viral replication. Additionally,
clinical findings in COVID-19 patients support its efficacy to reduce
clinical symptoms of COVID-19.We suggest that further optimally powered
randomized clinical trials should be carried out to come up with definitive
conclusions.
Blunt Traumatic Aortic Injury: 10-Year Single-Center Experience
Authors: Topcu Ahmet Can , Ozeren-Topcu Kamile , Bolukcu Ahmet , Sahin Sinan , Seyhan Avni U. , Kayacioglu Ilyas
Published: March 2021

Objective In blunt trauma patients, injury of the thoracic aorta is the second most common cause of death after head injury. In recent years, thoracic endovascular aortic repair (TEVAR) has largely replaced open repair as the primary treatment modality, and delayed repair of stable aortic injuries has been shown to improve mortality. In light of these major advancements, we present a 10-year institutional experience from a tertiary cardiovascular surgery center.

Methods Records of patients who underwent endovascular or open repair of the ascending, arch or descending thoracic aorta between January 2009 and December 2018 were retrospectively analyzed. Patients without blunt traumatic etiology were excluded. Perioperative data were retrospectively collected from patient charts. Long-term follow-up was performed via data from follow-up visits and phone calls.

Results A total of 1,667 patients underwent 1,740 thoracic aortic procedures (172 TEVAR and 1,568 open repair). There were 13 patients (12 males) with a diagnosis of blunt thoracic aortic injury. Mean patient age was 43.6 years (range, 16–80 years). Ten (77%) patients underwent TEVAR, two (15.4%) underwent open repair, and one (7.7%) was treated nonoperatively. Procedure-related stroke was observed in one (7.7%) case. Procedure-related paraplegia did not occur in any patients. Left subclavian artery origin was covered in seven patients. None developed arm ischemia. Hospital survivors were followed-up for an average of 60.2 months (range, 4–115 months) without any late mortality, endoleak, stent migration, arm ischemia, or reintervention.

Conclusion Blunt thoracic aortic injury is a rare but highly fatal condition. TEVAR offers good early and midterm results. Left subclavian artery coverage can be performed without major complications.
Calcium Silicate-Based Sealers Do Not Reduce the Risk and Intensity of Postoperative Pain after Root Canal Treatment when Compared with Epoxy Resin-Based Sealers: A Systematic Review and Meta-Analysis
Authors: Sponchiado Junior Emílio Carlos , Vieira Walbert de Andrade , Normando Ana Gabriela Costa , Pereira Juliana Vianna , Ferraz Caio Cezar Randi , Almeida José Flávio A. , Marciano Marina Angélica , Gomes Brenda P.F.A. , de-Jesus-Soares Adriana
Published: March 2021

This review aims to evaluate whether root canal obturation with calcium silicate-based (CSB) sealers reduces the risk and intensity of endodontic postoperative pain when compared to epoxy resin-based (ERB) sealers. The review was registered at PROSPERO (CRD42020169255). Two independent reviewers conducted an electronic search in PubMed, Scopus, EMBASE, Web of Science, Cochrane Library and LILACS until November 2020 and included only randomized clinical trials with adult health participants undergoing root canal treatment. After selection, the JBI Critical Appraisal tool was used to assess the risk of bias. A fixed-effect meta-analysis was performed to summarize the results of pain risk and pain intensity at time intervals of 24 and 48 hours. Finally, the certainty of evidence was assessed using the GRADE approach. The search resulted in 1,206 records, of which five studies (n = 421 patients) met the eligibility criteria and presented moderate to low risk of bias. There was no significant difference between groups in the risk of pain in the first 24 hours (relative risk or RR = 0.83, 95% confidence interval or CI: 0.60, 1.16, I 2 =) or 48 hours (RR = 0.56, 95% CI: 0.26, 1.21, I 2 =). Silicate-based sealers led to lower pain intensity only at 48 hours (mean and standard deviation = 0.37, 95% CI: 0.69, 0.05). All analyses revealed low heterogeneity (I 2 < 25%). The evidence presented moderate level of certainty. Currently available evidence has shown that there is no difference between CSB and ERB sealers in the risk or intensity of postoperative pain.
Anemia after Pediatric Congenital Heart Surgery
Authors: Jutras Camille , La Kim Anh , Gerardis George , Richard Rachel , Pont-Thibodeau Geneviève Du
Published: March 2021

The postoperative course of infants following congenital heart surgery is associated with significant blood loss and anemia. Optimal transfusion thresholds for cardiac surgery patients while in pediatric intensive care unit (PICU) remain a subject of debate. The goal of this study is to describe the epidemiology of anemia and the transfusion practices during the PICU stay of infants undergoing congenital heart surgery. A retrospective cohort study was performed in a PICU of a tertiary university-affiliated center. Infants undergoing surgery for congenital heart disease (CDH) before 6 weeks of age between February 2013 and June 2019 and who were subsequently admitted to the PICU were included. We identified 119 eligible patients. Mean age at surgery was 11 ± 7 days. Most common cardiac diagnoses were d-Transposition of the Great Arteries (55%), coarctation of the aorta (12.6%), and tetralogy of Fallot (11.8%). Mean hemoglobin level was 14.3 g/dL prior to surgery versus 12.1 g/dL at the PICU admission. Hemoglobin prior to surgery was systematically higher than hemoglobin at the PICU entry, except in infants with Hypoplastic Left Heart Syndrome. The average hemoglobin at PICU discharge was 11.7 ± 1.9 g/dL. Thirty-three (27.7%) patients were anemic at PICU discharge. Fifty-eight percent of patients received at least one red blood cell (RBC) transfusion during PICU stay. This study is the first to describe the epidemiology of anemia at PICU discharge in infants following cardiac surgery. Blood management of this distinctive and vulnerable population requires further investigation as anemia is a known risk factor for adverse neurodevelopment delays in otherwise healthy young children.
Impact of Transcatheter Aortic Valve Implantation on Thrombin Generation and Platelet Function
Authors: Mourikis Philipp , Dannenberg Lisa , Veulemans Verena , Zako Saif , Helten Carolin , M‘Pembele René , Richter Hannah , Hohlfeld Thomas , Jung Christian , Zeus Tobias , Kelm Malte , Polzin Amin
Published: March 2021

Background Transcatheter aortic valve implantation (TAVI) is an evolving treatment of severe aortic valve stenosis. However, thromboembolic events such as stroke are common, predominantly early after TAVI. Optimal periprocedural antithrombotic regime is unknown. Especially, as antithrombotic medication enhances bleeding risk, thrombin generation and platelet function are crucial in the pathogenesis of ischemic events. However, the impact of the TAVI procedure on thrombin formation and platelet reactivity is not known by now.

Methods We evaluated thrombin levels using thrombin–antithrombin (TAT) complexes and prothrombin fragments (PTFs) using enzyme-linked immunosorbent assay. Furthermore, platelet reactivity was measured via light transmission aggregometry before and 2 hours after TAVI in 198 patients.

Results TAT complexes and PTF F1 + 2 substantially increased during TAVI. Postprocedurally, TAT complexes and PTF were significantly higher after TAVI compared with percutaneous coronary intervention due to acute myocardial infarction, while preprocedural TAT complexes and PTF F1 + 2 did not differ. In contrast, platelet reactivity was not altered early after TAVI. Only adenosine diphosphate-induced aggregation was reduced, reflecting preprocedural loading with clopidogrel.

Conclusion In this pilot study, we were able to demonstrate that thrombin generation is significantly increased early after TAVI, while platelet function is not affected. Increased thrombin concentrations may contribute to the high risk of postprocedural thromboembolic events. This leads to the hypothesis that extended peri-interventional anticoagulation early after TAVI may be an approach to reduce thromboembolic events.
Norovirus Causes Pediatric Encephalopathy and Status Epilepticus: A Case Report and Review of the Literature
Authors: Tantillo Gabriela , Kagita Navyamani , LaVega-Talbott Maite , Singh Anuradha , Kaufman David
Published: March 2021

Norovirus is a common cause of acute gastroenteritis outbreaks worldwide. The disease can present with varying degrees of neurologic impairment from benign convulsions to rare cases of severe encephalopathy. In this article, we described a case report of a North American infant who presented with norovirus gastroenteritis, status epilepticus, severe encephalopathy, and abnormal but reversible diffusion restriction changes on magnetic resonance imaging of brain.
Does Having Rotavirus Infection in Early Childhood Increase the Risk of Celiac Disease?
Authors: Keceli Basaran Meryem , Dogan Caner , Bal Mahmut , Geylani Gulec Seda , Urganci Nafiye
Published: March 2021

Objective With the increasing prevalence of celiac disease (CD) in the population, possible risk factors are under investigation. Environmental and genetic factors that trigger the immune response have been analyzed for many years. This study investigated the presence of CD in children with rotavirus infection. Rotavirus infection is thought to be a risk factor for CD.

Methods Included in the study were 105 of 160 pediatric patients hospitalized due to symptomatic rotavirus infection between 2012 and 2018. These children were screened for CD 45.6 ± 18.2 (14–90) months following the rotavirus infection diagnosed with CD as per ESPGHAN guidelines.

Results A total of 105 pediatric patients who had rotavirus gastroenteritis were included in the study. The age of the children with rotavirus infection was 3.98 ± 1 (2–6) months. In terms of CD, it was 45.6 ± 18.2 months. Around 14 to 90 months later, patients were called for control. CD developed in four (3.8%) of the children with rotavirus, whereas none of the children in the control group developed CD.

Conclusion Rotavirus infection may be a risk factor for CD through immune mechanisms. There are genetic and various environmental factors for the development of CD. Although the CD's occurrence on children who had rotavirus gastroenteritis in our study also supported this situation, there was no statistically significant difference.
Wrist Arthrolysis: A Systematic Review of Open and Arthroscopic Techniques
Authors: Guidi Marco , Luchetti Riccardo , Besmens Inga , Rothenfluh Esin , Calcagni Maurizio
Published: March 2021

Background Wrist arthrolysis is a viable option in wrist stiffness and can be performed via open or arthroscopic techniques.

Purpose The aim of the study is to describe and evaluate the available techniques of open and arthroscopic arthrolysis of the radiocarpal joint and the distal radio ulnar joint (DRUJ) in posttraumatic wrist stiffness.

Methods A systematic literature search was performed in PubMed to identify studies reporting on open and arthroscopic wrist arthrolysis. Key words included “open wrist arthrolysis,” “arthroscopic wrist arthrolysis,” “post-traumatic wrist stiffness,” and “DRUJ arthrolysis.” Data were extracted independently by a pair of reviewers.

Results Overall, 637 studies were identified; 13 additional articles were found through previous publications (total 650 articles). A total of 612 records resulted after duplicates was removed. Fourteen studies were selected and only eight respected the inclusions criteria. One study focused on volar open arthrolysis and four studies on arthroscopic arthrolysis of the radiocarpal joint; two studies reported on open arthrolysis and two studies on arthroscopic DRUJ arthrolysis. Range of motion following open and arthroscopic wrist arthrolysis improved in all studies.

Conclusion Both arthroscopic and open arthrolysis can lead to similar and satisfactory results in radiocarpal joint and DRUJ stiffness..

Level of Evidence This is a level 3a study.
Evaluating Immediate and Short-Term Postoperative Clinical Outcomes of Patients Undergoing Ulnar Shortening for Ulnar Impaction Syndrome Using PROMIS
Authors: Bernstein David N. , Lander Richard D. , Hammert Warren C.
Published: March 2021

Background The early recovery trajectory of patients undergoing ulnar shortening for ulnar impaction syndrome using the Patient-Reported Outcomes Measurement Information System (PROMIS) is unknown.

Questions/Purposes Using PROMIS Upper Extremity (UE), Physical Function (PF), Pain Interference (PI), and Depression, we asked (1) do patients undergoing operative management for ulnar impaction syndrome present at their preoperative visit with notable impairment?; (2) At immediate follow-up, do patients present with a clinically appreciable change in symptom severity?; and (3) At short-term follow-up, do patients present with a clinically appreciable change in symptom severity?

Materials and Methods We identified patients from 01/2017 to 12/2019 at our institution undergoing ulnar shortening for ulnar impaction syndrome who completed all PROMIS domains at a preoperative visit and at least one postoperative time point (i.e., less than 4 weeks and/or greater than 12 weeks). Distribution- and anchor-based minimal clinically important difference estimates were used to evaluate clinically appreciable changes in symptoms over time.

Results A total of 38 patients met our inclusion criteria. The average change in PROMIS UE, PF, PI, and Depression scores from preoperative to immediate postoperative follow-up were –3.8, –4.3, 3.2, and 0.5, respectively. However, by short-term follow-up, the average change in PROMIS UE, PF, PI, and Depression scores were 3.7, 3.2, –4.7, and –3.9, respectively.

Conclusions Patients have worsening function at the immediate postoperative follow-up. By short-term postoperative follow-up, functional status and PI levels improve. Our findings can help hand surgeons provide evidence-based guidance on expected initial recovery following operative management for ulnar impaction syndrome.

Level of Evidence This is a level II, prognostic study.
Outcomes following Distal Radius Fractures with Preexisting Ulnocarpal Abutment
Authors: Samade Richard , Farrell Nolan , Zaki Omar , Farrar Nicholas , Goyal Kanu S.
Published: March 2021

Background Due to the commonality of distal radius fractures (DRFs), the potential impact of ulnocarpal abutment (UA) on patient outcomes is significant, whether it developed after or prior to injury. It is, therefore, important to consider whether preexisting UA has any impact on outcomes after an acute DRF.

Questions/Purpose The aims of this study were to determine if differences were present in (1) pain at final follow-up, (2) complications, and (3) unintended operations in patients with DRFs and either without or with preexisting radiographic UA.

Methods A single institution retrospective cohort study comparing patients treated either nonoperatively (43 patients) or operatively (473 patients) for DRFs between 5/1/2008 to 5/1/2018 was performed. Data included demographics, prior wrist pain or surgery, ulnar variance, select treatment data, and presence of pain, complication, or unintended operation by final follow-up. Statistical testing used Fisher's exact test and chi-squared test, with a significance level of 0.05.

Results The prevalence of preexisting UA was 14.0 and 15.6% in the nonoperatively- and operatively treated groups, respectively. In nonoperatively treated patients without or with UA, no differences in pain (37.8 vs. 33.3%, p = 1.00) or complications were seen (13.5 vs. 50.0%, p = 0.07). A higher unintended operation rate for nonoperatively treated DRFs with UA, compared with those without, UA was seen (5.4 vs. 50.0%, p = 0.01). No differences in pain, complications, or unintended operations were seen between those without and with UA in the operatively treated group.

Conclusion Preexisting UA is not associated with pain, complications, or unintended operations after operative treatment of DRFs. Prospective studies further evaluating outcomes in nonoperatively treated DRFs with UA may be beneficial.
The Incidence of Psychologic Stress following a Fall and Surgical Treatment of Distal Radius Fractures
Authors: Schindelar Lili , Katt Brian , Townsend Clay , Imbergamo Casey , Takei Robert , Beredjiklian Pedro
Published: March 2021

Background and Purpose Experiencing a fall and a subsequent distal radius fracture can have a major impact not only on patients' physical function, but also on their emotional state. The purpose of this project was to describe the prevalence of fear of falling (FoF) and posttraumatic stress disorder (PTSD) following surgically managed distal radius fractures due to a fall.

Methods Patients who underwent surgery for a distal radius fracture due to a fall were identified by a database query. Patients were divided into three groups based on time from surgery: 0 to 2 weeks (acute), 3 to 6 months (mid-term), and 12 to 15 months (long-term). FoF was measured using the Falls Efficacy Scale-International (FES-I) questionnaire. PTSD was measured using the PTSD Checklist for Diagnostic and Statistical Manual of Mental Disorders (DSM) Text Revision-5 (PCL-5) questionnaire. A total of 239 patients who met inclusion criteria were consented via phone and completed the emailed surveys.

Results FES-I scores were significantly higher in the acute group versus the long-term group (p = 0.04). High concern for FoF was observed in 63% (19/30) of patients in the acute group, in 35% (14/40) in the mid-term group (p = 0.019 vs. acute), and in 19% (8/42) in the long-term group (p < 0.001 vs. acute). Probable PTSD was observed in 2.3% (1/44) of patients in the acute group, in 4.8% (2/42) in the mid-term group, and in 7.3% (3/41) in the long-term group.

Conclusion Patients who undergo surgical fixation of a distal radius fracture due to a fall are subject to FoF and PTSD symptoms. To maximize postoperative outcomes, it is important for surgeons to be aware of these psychological effects and know how to screen for them.

Level of Evidence This is a Level III study.
Corporate reconstructions of federal macroeconomic government institutions compared: USA then, Europe Now
Authors: Georgiou Christakis
Published: March 2021

This paper is a contribution to the comparative historical literature on the development of American and European federal macroeconomic government institutions, spawned by the 2010–12 Eurozone crisis. The literature has two major shortcomings, namely a lack of agreement on relevant periodization and a lack of causal explanations about the sources of the processes being compared. My claim is that the most relevant comparison is between the first half of the twentieth century for the USA and the period beginning in the 1980s for the European Union. The reason for this is the underlying and profound socio-economic process of the corporate reconstruction of American and European capitalisms, which I identify as the root cause of the development of federal macroeconomic government institutions in both polities.