bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on the construction ventilation scheme of concealed subway station
Authors: Wang Chen , Zhao Jian-hui , Li Ze-hua , Chen Jia-mei , Liu Pan-xue
Published: July 2021

With the development of underground transportation, in order to reduce the impact on the surrounding environment and traffic, Hejiaying subway island station adopts the concealed excavation method. During the construction process, considering the construction method, tunnel layout, ventilation requirements, and the construction working face as a multi-conductor cave, more stringent requirements are put forward for the construction ventilation of the tunnel. Through the combination of theoretical calculation and numerical simulation, a ventilation method suitable for the actual construction conditions at the site was developed. After applying the scheme to practice, the feasibility of the scheme was verified through the determination of field data, and the improvement of the construction environment for tunnel personnel was achieved, which has certain reference value for similar projects.
A Real-Time Structural Damage Detection method for High-Pile Wharf Foundations
Authors: Liu Yongcheng , Zheng Yonglai , Zhou Yujue
Published: July 2021

As one of the most common structural forms in port engineering, the operation environment of high-pile wharf is quite harsh and complex, and its pile foundation often produces structural damage of different degrees. Until now, there is a lack of efficient, safe and economic damage detection methods. A novel and precise real-time structural damage detection (SDD) method using both finite element modelling (FEM) and 1D convolutional neural networks (CNNs) is established in this study. The results indicate that the proposed method could accurately identify the presence and location of damage in real time. The results also demonstrated that the proposed 1D CNNs based model are more sensitive to the longitudinal and lateral displacement responses of the high-pile wharf structure.
Disease Evaluation of Existing Tunnel Lining Based on AHP-Extenics
Authors: Wu Danhong , Wu Li , Ma Chenyang , Wang Yufeng , Lei Dexin , Jia Lin , Wang Jing
Published: July 2021

The existing tunnel lining structure is easily affected by geological conditions, disturbance in the early stage of construction and operation in the later stage. This paper analyzes the main factors affecting the lining structure diseases of existing tunnels from three aspects of engineering construction, natural environment and engineering geology, starting from 13 independent factors affecting the lining structure diseases of existing tunnels. First of all, the index system of the formation factors of lining diseases in the reconstruction and expansion tunnel is established by using the analytic hierarchy process (AHP), and the hierarchical index system is put forward. Based on AHP-Extenics model, the evaluation method of lining structure disease of existing tunnel is proposed. Then, combined with engineering practice and expert scoring, the weight of safety evaluation index is determined, and the safety evaluation index and weight are expanded by using correlation function. Finally, the disease evaluation grade of the existing tunnel lining structure is obtained. This method uses the formal Extenics comprehensive evaluation model, which makes the calculation results more objective and provides a new method for the disease evaluation of the existing tunnel lining structure.
Research on the influence of manufactured sand gradation on concrete performance
Authors: Kai-ren Li , Ping-Li Hua
Published: July 2021

Based on experiments of C30 concrete with manufactured sand, this paper studied on the workability and compressive strength of the manufactured sand concrete with 7 different fineness modulus and different weight fractions (0%, 2%, 4%, 6%, 8%, 10%) of stone powder. The results show that the fineness modulus and the stone powder content in the gradation parameters of manufactured sand have great effects on the concrete performance. When the fineness modulus of manufactured sand is about 2.8, the workability and compressive strength of concrete can be improved. As the content of stone powder increases, the workability and compressive strength of concrete firstly increase and then decrease, and the optimal weight fraction of stone powder is about 6%. The research results can provide reference for the production and application of gneiss manufactured sand.
Study on the influencing factors of existing buildings green renovation in old residential areas
Authors: Yanping Yin , Hao Gu , Xiangyang Gu
Published: July 2021

Based on problems existing in the green transformation of existing buildings in old residential areas, this paper aims to find out the influencing factors that hinder the green transformation of existing buildings in old residential areas, so as to change the situation that the green transformation of existing buildings in old residential areas advances slowly. It uses the grounded theory based on “science and technology literature” and factor analysis method to determine the 16 key influencing factors and importance ranking, reliability test and validity test, and calculates the initial load square sum of squares, rotating load characteristic value, and the cumulative value indicators to extract six common factors and put forward some proposals for the results obtained from the analysis. Furthermore, it provides decision-making reference for the implementation of green transformation of existing buildings in old residential areas.
Application of hydration heat inhibitor in crack control of mass concrete of tunnel side wall
Authors: Wang XiZhi , Shi MinSheng , Wang XinGang
Published: July 2021

The structural deformation caused by temperature change is the main reason for cracking of mass concrete. In order to avoid or reduce the crack of the side wall of cast-in-place mass concrete in tunnel, the effects of different dosage of hydration heat inhibitor on the internal temperature rise curve of concrete, strength and the properties of the mixture are analyzed through experimental research, and the optimal dosage of 1% of cementing material is finally determined. The engineering application results show that after adding hydration heat inhibitor to the tunnel side wall concrete, the maximum temperature rise in the tunnel side wall is obviously reduced, and the arrival time of the temperature peak is delayed. No cracks appear in the tunnel side wall, and the crack control effect is good.
Study on early warning of rapid sinking of large land caisson in silt layer
Authors: zhangru Shi , Xiaoteng Liang , Zuhao He , Min Qiu
Published: July 2021

Large caisson constructed in the soft soil layer is prone to rapid sinking during the sinking process. Rapid sinking is often accompanied by partial sinking, which affects construction safety and subsequent construction. There is no relevant early warning mechanism for early warning of rapid sinking. This paper takes the sinking construction of a large land caisson in a deep silt layer as an example, analysis the rapid sinking mechanism through the earth pressure and settlement rate of the sinking process, and proposes a rapid sinking early warning mechanism. Before the rapid sinking, the soil at the edge of the blade feet is partially plastic damaged, and the earth pressure decreases continuously after reaching its limit value; The strain softening of the overlying soft soil layer, the rapid reduction of side friction and the instability of open caisson caused by soil gushing after the plastic zone connecting are the important reasons for the rapid sinking. The rapid sinking process is divided into “sagging section, starting section, instability section and stable section”. The earth pressure early warning mechanism is the continuous decrease of the earth pressure at the blade feet. When the sinking rate exceeds the threshold value for two hours, it is regarded as the early warning mechanism of sinking rate. Using this dual control mechanism of end earth pressure and sinking rate can effectively warn the rapid sinking of the caisson.
Analysis of Common Problems of Noise and Vibration in Building Heating Ventilation Air Conditioning Design
Authors: Ruan Xiaolong , Yin Yisong
Published: July 2021

With the continuous growth of my country's economy and the continuous improvement of the people's economic level, the demand for the design of heating, ventilation and air conditioning systems has also increased. The HVAC system is very important in the building environment. When optimizing the relevant design, it is necessary to always consider the design details of the HVAC system and adjust the integrity of the design, especially to take preventive measures in areas where noise and vibration may occur to avoid heating serious problems caused by noise and general vibration when the communication system is running. This article outlines how to avoid and control common noise and vibration problems when designing HVAC projects.
Experimental Study on Influence of Unloading Rate on Creep Characteristics of Marble under High Stress
Authors: He Huajun , Jin Huahui
Published: July 2021

In the engineering of high stress area, the measures to control the stability of surrounding rock by reducing excavation footage and excavation speed are to adjust the unloading rate of surrounding rock caused by excavation. In this study, unloading creep tests of marble under high stress conditions were carried out to study the effect of unloading rate. Research results showed that the axial and lateral instantaneous strain and creep strain of the sample increased with the increase of unloading rate; the lateral creep characteristic of marble under unloading condition was stronger than that of axial creep characteristic, and it was more obvious with the increase of unloading rate; the failure of specimens under unloading creep condition was mainly caused by the rapid increase of lateral strain, and the brittleness of rock was increasing with the increase of unloading rate. The Burgers model was used to describe the creep curves of specimens, and the variation of the parameters with the unloading rate was analyzed. The fitting results showed that the instantaneous elastic modulus E1, E'1 and the viscosity coefficients η1, η'1 all decreased with the increase of the unloading rate, which can be described by linear relationship within the unloading rate range of this experiment. Compared with the time of whole creep tests, the time for each specimen to enter the steady-state creep was similar, it was considered that the effect of unloading rate on η2/E2 and η'2/E'2 can be ignored.
Countermeasures for safe navigation of large ships in restricted water
Authors: Xingtao Xie , Xiuwen Liu , Yongchao Liu , Xin Luan
Published: July 2021

With the development of social economy, my country's marine industry has also made considerable progress, and the trend of large-scale ships has become increasingly obvious. In recent years, people have paid more and more attention to the maneuverability of large ships, especially whether large ships can navigate safely in restricted waters. In order to ensure the navigation safety of large ships in restricted waters, this article analyzes the characteristics of restricted waters and the maneuverability of large ships themselves, and analyzes the causes of some maritime accidents. It points out the navigation risks of large ships in restricted waters and proposes safe navigation. Countermeasures: Reasonably adjust the speed and timing of rudder use; maintain a reasonable quay wall distance; maintain a reasonable draught difference; make careful sailing preparations.
Research on age-friendly garden design in China based on the case study of WANSHOU Park
Authors: Liu Chengyang
Published: July 2021

The rate of population aging has reached a high level in China that age-friendly design should be concerned when designing gardens in urban place. Although the generation-skipping guardianship phenomenon always exists in present situation of elderly people in China that grandchildren are taken with the elderly and are involved in their daily activities in most family, the needs of children are neglected in urban garden design. The paper generalized guidelines of age-friendly garden design according to LEED, Chinese garden design standard, and the guideline of global age-friendly cities in Europe. Childrenfriendliness have also been included based on the above-mentioned new guidelines. 29 reports have been collected in the case study of WANSHOU Park which can be characterized as an age-friendly garden involving basic information and scoring records on its environment and facilities. Through the increasement of children-friendly features and installments in the park, the design will have great potential to deal with aging problems.
Analysis on the General Conception and Planning of the Road Trip Campsite along the Land Silk Road in China
Authors: Li Yanjun , Ge Minglan
Published: July 2021

This article is based on the cultural background of the land section of the "Silk Road" and the surrounding status quo research basis, combined with its own characteristics of tourism resources, folk culture and traffic conditions, establish a self-driving camping site system in the five provinces of Shaanxi, Gansu, Ningxia, Qinghai and New Zealand on the domestic section of the "Silk Road". This paper summarizes the current situation and constraints of campsites in each province through data collection, data analysis and field investigation. On this basis, we put forward the overall construction and planning ideas of the camp. The purpose is to scientifically, reasonably and orderly plan the construction scheme of road trip routes, camping sites and campsites along the Silk Road.This will further promote the healthy development of tourism and cultural experience in the areas along the Silk Road, provide convenient and safe travel routes and recreation environment for tourists, but also improve the economy and people's living standards in the areas along the route.
Comprehensive Analysis of Technical Management of Urban Underground Rail Transit Construction: A Case Study of Chengdu Metro Line 17
Authors: Yu Zhang
Published: July 2021

With the advancement and strengthening of urbanization, supercities are continually emerging; however, the traffic problems that accompany this growth actually hinder urban development. Thus, construction of an urban underground rail transit system is an important civil project for utilization of urban underground space. In particular, numerous railway and tunnel projects have been implemented in China during the past few decades with great progress made in rail transit construction technology. Nonetheless, many technical challenges have also been encountered in areas of design, construction, safe operation, and maintenance. To examine such problems, the Phase I project of China’s Chengdu Metro Line 17 is comprehensively analyzed as a case study, and an in-depth discussion is given on the construction technology and technical management practices. The data obtained in the management process are classified and archived to form a complete dataset of technical project management. After the project is completed, the experience and lessons in technical management will be summarized to form reference material for similar projects in the future.
Research on Observation of Settlement Deformation of Zhengzhou-Jinan High-speed Railway and Information Platform of Observation Data
Authors: Xiuyong Ni
Published: July 2021

In order to provide data support for engineering construction, this paper proposes to study the construction of information platform of settlement deformation observation data. In this paper, the information platform for observation data is established based on the settlement deformation data of Zhengzhou-Jinan high-speed railway. The results show that the settlement deformation observation platform in this paper can effectively integrate the data and ensure the accuracy of the data. This paper sets an example for the future research on the construction of information platform of high-speed railway settlement.
Research on the Impact of Industrial Development on Energy Utilization Efficiency under the Background of Urban Agglomeration Planning
Authors: Zheng Yuan , Yue Bo , Han Xuesong , Li Zheng
Published: July 2021

At present, the trend of central cities leading the development of urban agglomerations and urban agglomerations driving regional development is becoming more and more significant. Based on the panel data of 16 cities in the Chengdu-Chongqing urban agglomeration from 2010 to 2015, this paper uses a fixedeffect model to study the relationship between industrial development and energy efficiency in urban agglomerations, central cities, and surrounding cities. The empirical results show that for the overall urban agglomerations, central cities and surrounding cities, the scale of the secondary industry has a negative correlation with energy consumption per unit of GDP. Industrial development will increase the total energy consumption, but it also contributes to energy efficiency. In order to achieve the goal of "carbon peak and carbon neutrality", cities must find a balance in development and seek ecological protection during development.
Research on metro passenger flow route selection model based on passengers' familiarity with road network
Authors: Liu Yiting , Jia Shunping
Published: July 2021

Road network familiarity is a key attribute that affects passengers’ travel route choice. This paper constructs a differentiated travel generalized cost function based on the passenger’s road network familiarity and the influencing factors of route choice, and uses the Regret Theory to construct a route choice model. By setting passenger decision-making rule weights increase the flexibility of the model. The paper uses the method of combining RP survey and SP survey to conduct route selection behavior survey and calibrate model parameters. Finally, the prediction results before and after the passenger classification are compared with the survey data. The prediction error value is 5.98%, and the prediction accuracy after passenger classification is improved by 6.03%. The effectiveness of the prediction model is verified and the necessity of passenger classification is verified.
Analysis Model of Conventional Public Transport Hub Based on Grey Correlation Degree
Authors: Zhuomin Dai
Published: July 2021

With the continuous progress of urbanization in China, the urban public transport system has been developing in the direction of three-dimensional and diversified. As a physical carrier of various modes of transportation, the layout and operation efficiency of urban public transport hub directly affect the smoothness of the whole line network. In view of this, this paper carries out systematic analysis of the conventional bus hub and establishes an evaluation index system which can reflect the normal bus hub system effectively; Then, the paper evaluates the operation efficiency of the conventional bus hub system by using the grey correlation analysis theory; Finally, the case analysis is carried out to calculate the comprehensive evaluation value of the object and sort it. The results show that the positive indicators are the per capita transfer area, parking facility rate, transfer sign facility rate and transfer information timeliness. The results of this paper supplement and perfect the current analysis model of public transport hub. The results of the case study show that the model has a high practical value.
Research on the application of Chinese traditional pattern cloud pattern in Landscape Sketch
Authors: Li Zhigang , Yang Zhonggui
Published: July 2021

This paper discusses the application of traditional auspicious pattern cloud pattern in landscape sketch design. On the one hand, the purpose is to inherit the form aesthetic feeling and cultural connotation of cloud pattern, so as to apply the traditional cultural innovation in today's design and show our cultural confidence; on the other hand, to provide new ideas for the form innovation of landscape sketch, so as to design a set of cultural It is of great significance to integrate the value and aesthetic conception of landscape sketch, so as to meet the requirements of today's people for high-quality life. This electronic document is a “live” template. The various components of your paper [title, text, heads, etc.] are already defined on the style sheet, as illustrated by the portions given in this document.
Overturning stability of supported geomembrane tube for flood control
Authors: Gao Xin , Sun Liqiang , Guo Wei , Ren Ruxiao , Zeng Wenqian
Published: July 2021

As a kind of rapid filling hydraulic structure, geomembrane tube can effectively act as flood barriers and cofferdams for flood risk management. L-shaped block is used to support geomembrane tube to prevent it from rolling. The contact force between the L-shaped block and the geomembrane tube is analyzed by using particle flow code (PFC2D) software, and the overturning stability of the L-shaped block is calculated. The relationship between the key factors and the overturning stability was established. It is found that the central angle of the L-shaped block has little influence on the overturning stability. The overturning stability decreases with the increase of the initial pumping pressure. Keeping Lw/Lb unchanged, increasing Lb will improve the overturning stability where Lw and Lb are the width and the height of the Lshaped block. Under the ultimate water level, when 1.23 Lbcr < Lw≤1.55 Lbcr, the L-shaped block is in the state of overturning stability where Lbcr is the critical height of the L-shaped block. The initial pumping pressure is less than 0.152γL, the L-shaped block is in the state of overturning stability with Lw/Lbcr =1.0 where L is the cross-sectional perimeter of the geomembrane tube and γ is the unit weight of the filling liquid, on the contrary, Lw/Lbcr must be greater than 1 to ensure its overturning stability.
Impacts of the Covid-19 on the IRPA young generation activities in radiation protection: testimonies and experience feedback
Authors: Andresz S. , Kabrt F. , Sáez-Muñoz M. , Nusrat O. , Papp C.
Published: July 2021

The measures implemented to limit the spread of Covid-19 have brought many challenges on the work organization, the radiation protection being no exception. The IRPA Young Generation Network has investigated through a collection of testimonies the impacts of these measures and how the continuity and consistency of radiation protection was ensured. This article presents the results of the analysis of the testimonies. The impacts of the Covid-19 for each of the radiation protection related sectors covered by the survey are presented from a young generation perspective. The impacts are never negligible and even more important in some sectors and for some type of work. The adaptations made to the radiation protection and how they were implemented are shown, as well as the lessons-learned from these unprecedented circumstances.
Dysgnathiechirurgie digital – Operationsschablonen und patientenspezifische Implantate
Authors: Schramm Alexander , Pietzka Sebastian , Wilde Frank
Published: July 2021

Die modernen Techniken des 3D-Druckverfahrens ermöglichen den Einsatz von Operationsschablonen und patientenspezifischen Implantaten. Basierend auf 3-dimensionalen Bilddatensätzen der Patienten (optische Scans, CT- oder DVT-Datensätzen) können komplexe bignathe Umstellungsoperationen sowie Kinnplastiken virtuell geplant und intraoperativ geführt umgesetzt werden. Durch die Verwendung CAD/CAM generierter Osteotomie- und Bohrschablonen und patientenspezifischer Osteosyntheseplatten besteht seit dem Jahr 2015 erstmals auch die Möglichkeit bei komplexen bignathen Operationen die Maxilla splintfrei in allen 3 Dimensionen planbar, präzise und reproduzierbar einzustellen. Die validierten Präzisionsdaten zu Planung und Endergebnis liegen signifikant unter denen der 2D-geplanten Operationen. Die Techniken der splintfreien Oberkieferpositionierung und schablonengeführten Kinnverlagerung ermöglichen erstmals und routinehaft die präzise Umsetzung des präoperativen Planes bei der Dysgnathieoperation, insbesondere im Ausbildungsbetrieb.
Individuelle Gewichtung der Parameter im Rahmen der kieferorthopädischen Ex/NonEx-Entscheidung
Authors: Paddenberg Eva , Klinke Rebecca , Proff Peter , Kirschneck Christian
Published: July 2021

Der Zahnengstand gehört zu den häufigsten Malokklusionen, sodass die Kieferorthopädie täglich vielfach mit der Frage der Platzbeschaffung konfrontiert wird. Bei ausgeprägtem Platzmangel ist die Entscheidung einer Ex/Non-Extraktionstherapie zu treffen. Diese hängt von den individuellen morphologisch-anatomischen sowie funktionellen Gegebenheiten ab. Durch die Berücksichtigung einer Vielzahl einzelner Befundparameter soll eine größtmögliche Entscheidungssicherheit erzielt werden. Hinzu kommt die Analyse alternativer Möglichkeiten der Platzbeschaffung. Neben dem systematischen Algorithmus liegt ein besonderes Augenmerk auf der individuellen Gewichtung der Befundparameter, was letztendlich in hohem Maße die klinische Erfahrung fordert.
Tabakentwöhnung und Verordnung von ambulantem Lungensport im Rahmen der pneumologischen Rehabilitation in Deutschland
Authors: Hayden Markus C. , Limbach Matthias , Glöckl Rainer , Dewey Stefan , Rupp Alexander , Schultz Konrad
Published: July 2021

Ziel der Studie Diese Erhebung der Sektion 12 der DGP dient der Erfassung der Angebote der Tabakentwöhnung (TEW) und der Verordnung von Rehabilitationssport (Lungensport) als Reha-Nachsorge im Rahmen der pneumologischen Rehabilitation in Deutschland.

Methodik Es erfolgte eine postalische Befragung sämtlicher pneumologischer Rehabilitationskliniken in Deutschland. 67 Kliniken wurden kontaktiert, von denen 62 die Einschlusskriterien erfüllten und 62,9 % die Fragebögen zurücksandten.

Ergebnisse Alle Kliniken beurteilen Lungensport als effektive Maßnahme zur Reha-Nachsorge. Jeweils 56,4 % führen hierzu regelmäßig standardisierte Informationsveranstaltungen durch bzw. verteilen entsprechende Informationsbroschüren. 38,5 % der Einrichtungen bieten ambulante Lungensportgruppen an. Der Anteil der Rehabilitanden, die bei Entlassung eine Lungensport-Verordnung erhält, erstreckt sich über das gesamte Spektrum von 0–100 %. Nur jede vierte Klinik gab an, schon einmal von Kostenträgern nach den Ergebnissen der Trainingstherapie gefragt worden zu sein.

Sämtliche Kliniken erheben den Rauchstatus der Patienten, zudem werden alle Raucher individuell über die Notwendigkeit einer Tabakabstinenz aufgeklärt. Der Anteil aktiver Raucher wurde auf 33 % geschätzt. In 69,2 % der Kliniken werden regelmäßig standardisierte Vorträge zur TEW durchgeführt, in 61,5 % regelmäßig verhaltenstherapeutische TEW-Gruppentherapien. Zusätzliche Angebote sind bedarfsweise psychologische Beratungen (89,7 %), routinemäßiges Angebot von Nikotinersatzpräparaten (61,5 %) bzw. Vareniclin (15,4 %). Eine Nachsorge wird nur von 10,3 % angeboten. Im Durchschnitt schätzten die Einrichtungen den Anteil an Rauchern, die während der Reha einen Rauchstopp erreichen können, auf 32 %. Seitens der Kostenträger wurde nur eine der Kliniken (2,6 %) schon einmal nach den Ergebnissen der TEW angefragt.

Schlussfolgerung Die vorliegende Untersuchung legt nahe, dass viele Rehabilitationskliniken bez. TEW und Verordnung von Lungensport schon einen guten Standard erreicht haben, zeigt aber auch bestehende Verbesserungspotenziale auf. Diese betreffen die Nachsorge bei der TEW sowie die noch nicht durchgängig etablierte Verordnung von Lungensport als Reha-Nachsorge.
Fertigungswege zur Herstellung einer Kieferorthopädischen Gaumennahterweiterungsapparatur – digitaler Workflow im Fokus
Authors: Bolkart Johannes , Spintzyk Sebastian , Mann Nils Kristian , Koos Bernd , Xepapadeas Alexander B.
Published: July 2021

Durch die stetige Weiterentwicklung digitaler Fertigungswege stehen zahlreiche Möglichkeiten zur Herstellung kieferorthopädischer Apparaturen zur Verfügung. Digitalisierte Arbeitsprozesse sind heutzutage aus der Zahnmedizin nicht mehr wegzudenken.

Unter Umgehung handwerklich-manueller Fehlerquellen offerieren die digitalen Systeme eine Steigerung der Qualität sowie Kosteneffizienz, bei gleichzeitig gesteigertem Patientenkomfort. Dabei ist die intraorale Datenerfassung von größter Wichtigkeit, da bereits hier die Weichen für den gesamten digitalen Workflow gestellt werden.

Bei der anschließenden Fertigung kann prinzipiell zwischen additiven und subtraktiven Verfahren unterschieden werden. In diesem Artikel sollen die gängigen CAM-Methoden anhand der Herstellungsmöglichkeiten einer Gaumennahterweiterungsapparatur dargestellt und verglichen werden.

Es konnte gezeigt werden, dass sich alle Fertigungsverfahren zur Herstellung einer Gaumennahterweiterungsapparatur eignen.
Lhermitte–Duclos Disease: Incidental Finding in Traumatic Cerebral Hemorrhage
Authors: Beniwal Hemant Kumar , Satish Thatikonda , Rao Gollapudi Prakash , Reddy Musali Siddartha , Manne Srikrishnaaditya
Published: July 2021

Lhermitte–Duclos disease, also known as dysplastic cerebellar gangliocytoma, is a rare hamartomatous tumor localized in cerebellum. An association with Cowden syndrome is observed in 50% of cases who present with symptoms of increased intracranial pressure and cerebellar ataxia. These patients have specific magnetic resonance imaging and histopathological findings. Surgical resection is the treatment of choice. Here, we report a case of a young female with traumatic frontal hemorrhage associated with Lhermitte–Duclos disease.
Influence of the Multiple Layers Application and the Heating of Silane on the Bond Strength between Lithium Disilicate Ceramics and Resinous Cement
Authors: Silva Uriel Paulo Coelho , Maia Andréa Peixoto , Silva Isaias Donizeti , Miranda Milton Edson , Brandt William Cunha
Published: July 2021

Objective This study aimed to evaluate the bond strength between lithium disilicate ceramic and resinous cement when silane (Prosil, FGM) was applied in different amounts of layers under heating or not.

Materials and Methods Sixty IPS E-max CAD ceramic (Ivoclar) was used. They were conditioned with 10% hydrofluoric acid for 20 seconds. The samples were distributed in six groups (n = 10): 1Sil, 1 layer of silane without heating; 1SilAq, 1 layer of silane with heating; 2Sil, 2 layers without heating; 2SilAq, 2 layers with heating; 3Sil, 3 layers without heating; and 3SilAq, 3 layers with heating. After each layer, a jet of cold air was applied for 20 seconds in groups 1Sil, 2Sil, 3Sil, and jet of hot air (50°C) in groups 1SilAq, 2SilAq, and 3SilAq. Subsequently, an adhesive layer was applied, and fourcylinders were made on the ceramic with a resin cement AllCemVeneer and photoactivated for 20 seconds. The samples were stored at 37°C for 24 hours and analyzed to the microshear test at EMIC.

Statistical Analysis Data were submitted to ANOVA and Tukey’s test (α = 0.05).

Results The results showed that there was no statistical interaction between the factors studied. The “heating” factor was not statistically significant; however, the “silane layers” factor showed differences between groups. The analysis of the results showed that the use of one (66%) or two layers (67%) of silane regardless of heating, produced higher values of bond strength, when compared with the group of three layers (62%).

Conclusion The use of silane with one or two layers provided a greater bond strength between lithium disilicate ceramic and resinous cement and that the heating did not influence the results.
Improved Medical Student Engagement with EHR Documentation following the 2018 Centers for Medicare and Medicaid Billing Changes
Authors: Stevens Lindsay A. , Pageler Natalie M. , Hahn Jin S.
Published: July 2021

Background Medical student note writing is an important part of the training process but has suffered in the electronic health record (EHR) era as a result of student notes being excluded from the billable encounter. The 2018 CMS billing changes allow for medical student notes to be used for billable services provided that physical presence requirements are met, and attending physicians satisfy performance requirements and verify documentation. This has the potential to improve medical student engagement and decrease physician documentation burden.

Methods Our institution implemented medical student notes as part of the billable encounter in August 2018 with support of our compliance department. Note characteristics including number, type, length, and time in note were analyzed before and after implementation. Rotating medical students were surveyed regarding their experience following implementation.

Results There was a statistically significant increase in the number of student-authored notes following implementation. Attending physicians' interactions with student notes greatly increased following the change (4% of student notes reviewed vs. 84% of student notes). Surveyed students reported that having their notes as part of the billable record made their notes more meaningful and enhanced their learning. The majority of surveyed students also agreed that they received more feedback following the change.

Conclusion Medical students are interested in writing notes for education and feedback. Inclusion of their notes as part of the billable record can facilitate their learning and increase their participation in the note writing process.
Cumulative Antimicrobial Susceptibility Data of Pseudomonas Aeruginosa Isolates from Cystic Fibrosis Patients: 4-Year Experience
Authors: Fidan Ebru , Alci Gamze , Koldaş Seda Sevilay , Karadag Bülent , Gökdemir Yasemin , Erdem Eralp Ela , Karahasan Yagcı Aysegül
Published: July 2021

Objective Pseudomonas aeruginosa is the most important cause of lung infection among cystic fibrosis (CF) patients, and to reduce the severity of the infection, facility-specific cumulative antibiograms could help clinicians in empirical treatment.

Methods Respiratory samples of CF patients between January 2015 and December 2018 were scanned through Laboratory Operating System retrospectively. Demographical data of patients, culture results, and antibiotic susceptibilities are recorded using Microsoft Excel 2010. Cumulative antibiogram data were obtained according to the CLSI M39A4 document.

Results The number of registered patients increased in 4 years from 154 to 253. The mean age of patients varied from 9 to 11.7 (range, 2–42). The ratio of patients with a positive culture for P. aeruginosa increased from 32 to 40%, and the mean patients' age decreased from 16.6 to 11.1 (p <0.05). A total number of 4,146 respiratory samples were analyzed. Sputum samples consisted of 42.5% (n: 1,767) of the samples with a 58.4% isolation rate of P. aeruginosa (n: 1,034). A notable increase of resistance was seen almost all antimicrobials tested by years. The ratio of multidrug-resistant (MDR) P. aeruginosa was 4.1, 10.2, 4.5, and 8.6% in 2015, 2016, 2017, and 2018.

Conclusion Antimicrobial resistance is a challenging problem in CF patients, and surveillance should be done regularly.
Efficiency and Safety of Patent Ductus Arteriosus Surgical Ligation in Extremely Low Birth Weight Infants Without Chest Tube Placement
Authors: Kourelis Georgios , Kanakis Meletios , Loukas Constantinos , Kakava Felicia , Kyriakoulis Konstantinos , Bobos Dimitrios , Apostolopoulou Sotiria , Rammos Spyridon , Giannopoulos Nikolaos
Published: July 2021

Patent ductus arteriosus (PDA) has been associated with increased morbidity and mortality in preterm infants. Surgical ligation (SL) is generally performed in symptomatic infants when medical management is contraindicated or has failed. We retrospectively reviewed our institution's experience in surgical management of PDA for extremely low birth weight (ELBW) infants without chest tube placement assessing its efficiency and safety. We evaluated 17 consecutive ELBW infants undergoing SL for symptomatic PDA (January 2012–January 2018) with subsequent follow-up for 6 months postdischarge. Patients consisted of 9 (53%) females and 8 (47%) males. Mean gestational age (GA) at birth was 27.9 ± 2.1 weeks. Median values for surgical age (SA) from birth to operation was 10 days (interquartile range [IQR]: 8–12); PDA diameter 3.4 mm (IQR: 3.2–3.5); surgical weight (SW) 750 g (IQR: 680–850); and days of mechanical ventilation (DMV) as estimated by Kaplan–Meier curve 22 days (95% confidence interval: 14.2–29.8). We observed a statistically significant negative association between DMV and GA at birth (rho = − 0.587, p = 0.017), SA (rho = − 0.629, p = 0.009) and SW (rho = − 0.737, p = 0.001). One patient experienced left laryngeal nerve palsy confirmed by laryngoscopy. Otherwise, there were no adverse events to include surgical-related mortality, recurrence of PDA, or need for chest tube placement during follow-up. SL of PDA in ELBW infants without chest tube placement is both efficient and safe. Universal consensus recommendations for the management of PDA in ELBW neonates are needed. Further study is required regarding the use of the less invasive option of percutaneous PDA closure in ELBW infants.
Subdural Hygroma in an Infant with Marfan's Syndrome
Authors: Ballmann Lisa , Scholl-Bürgi Sabine , Karall Thomas , Odri Komazec Irena , Karall Daniela , Michel Miriam
Published: July 2021

Based on a patient encounter in which genetically confirmed Marfan's syndrome (MFS) underlay a spontaneously resolving subdural hygroma (SDHy) diagnosed in infancy, we review the literature of MFS clinically manifest in early life (early-onset MFS [EOMFS]) and of differential diagnoses of SDHy and subdural hemorrhage (SDHe) at this age. We found that rare instances of SDHy in the infant are associated with EOMFS. The most likely triggers are minimal trauma in daily life or spontaneous intracranial hypotension. The differential diagnosis of etiologies of SDHy include abusive and nonabusive head trauma, followed by perinatal events and infections. Incidental SDHy and benign enlargement of the subarachnoid spaces must further be kept in mind. SDHy exceptionally also may accompany orphan diseases. Thus, in the infant, EOMFS should be considered as a cause of SDHe and/or SDHy. Even in the absence of congestive heart failure, the combination of respiratory distress syndrome, muscular hypotonia, and joint hyperflexibility signals EOMFS. If EOMFS is suspected, monitoring is indicated for development of SDHe and SDHy with or without macrocephaly. Close follow-up is mandatory.
Understanding perceptions of recovery from psychological distress in Sierra Leone through qualitative comparative analysis
Authors: Jailobaeva Kanykey , Horn Rebecca , Bah Abdulai Jawo , Loffreda Giulia , Ager Alastair
Published: July 2021

Qualitative comparative analysis (QCA) is a relatively new method that examines causal complexity. Its use in mental health research is nascent. In low-income and fragile settings, with weak mental health service provision, identifying pathways of recovery from psychological distress can inform the appropriate deployment of scarce community and public resources. This paper examines the use of QCA to identify predictors of recovery in Sierra Leone. Our study explored lay perceptions of the signs of recovery from psychological distress caused by such events as the loss of a family member, severe sickness, and loss of a relationship. The data drew upon 75 interviews with women and men, across four districts of Sierra Leone, who described the signs of recovery from psychological distress they have observed in one person known to them. The truth table generated through QCA software indicated two signs of recovery— work/study and healthy relations—to be the most prevalent across different combinations of predictive factors. Further analysis of the truth table and sub-set relations suggested that work/study and healthy relations frequently served as sufficient conditions for reported recovery from distress to occur. QCA provided a means to identify sufficient predictive factors for recovery from psychological distress to occur. The findings suggest that to enable recovery from psychological distress, support needs to be broad and bring together services that will enable individuals to improve their social and relational wellbeing. Responses to distress need to involve a wide range of community-based stakeholders who will help individuals to engage in constructive activity and strengthen relations with their family members, friends, and the broader community. QCA is potentially well-positioned to unpack complexity in mental health research.
Relations between moments for the Jacobi and Cauchy random matrix ensembles
Authors: Forrester Peter J. , Rahman Anas A.
Published: July 2021

We outline a relation between the densities for the β-ensembles with respect to the Jacobi weight (1 − x)a(1 + x)b supported on the interval (−1, 1) and the Cauchy weight (1−ix)η(1+ix)η̄ by appropriate analytic continuation. This has the consequence of implying that the latter density satisfies a linear differential equation of degree three for β = 2 and of degree five for β = 1 and 4, analogs of which are already known for the Jacobi weight xa(1 − x)b supported on (0, 1). We concentrate on the case a = b [Jacobi weight on (−1, 1)] and η real (Cauchy weight) since the density is then an even function and the differential equations simplify. From the differential equations, recurrences can be obtained for the moments of the Jacobi weight supported on (−1, 1) and/or the moments of the Cauchy weight. Particular attention is paid to the case β = 2 and the Jacobi weight on (−1, 1) in the symmetric case a = b, which in keeping with a recent result obtained by Assiotis et al. (“Moments of generalised Cauchy random matrices and continuous-Hahn polynomials,” Nonlinearity (to be published), arXiv:2009.04752) for the β = 2 case of the symmetric Cauchy weight (parameter η real), allows for an explicit solution of the recurrence in terms of particular continuous Hahn polynomials. Also for the symmetric Cauchy weight with η = −β(N − 1)/2 − 1 − α, after appropriately scaling α proportional to N, we use differential equations to compute terms in the 1/N2 (1/N) expansion of the resolvent for β = 2 (β = 1, 4).
Characterization of Agfa Structurix series D4 and D3sc x-ray films in the 0.7–4.6 keV energy range
Authors: Dutra E. C. , Cowan J. , Cunningham T. , Durand A. M. , Emig J. , Heeter R. F. , Knauer J. , Knight R. A. , Lara R. , Perry T. S. , Rodriguez Z. , Torres G. , Wallace M. S.
Published: July 2021

X-ray films remain a key asset for high-resolution x-ray spectral imaging in high-energy-density experiments conducted at the National Ignition Facility (NIF). The soft x-ray Opacity Spectrometer (OpSpec) fielded at the NIF has an elliptically shaped crystal design that measures x rays in the 900–2100 eV range and currently uses an image plate as the detecting medium. However, Agfa D4 and D3sc x-ray films’ higher spatial resolution provides increased spectral resolution to the data over the IP-TR image plates, driving the desire for regular use of x-ray film as a detecting medium. The calibration of Agfa D4 x-ray film for use in the OpSpec is communicated here. These calibration efforts are vital to the accuracy of the NIF opacity measurements and are conducted in a previously un-studied x-ray energy range under a new film development protocol required by NIF. The absolute response of Agfa D4 x-ray film from 705 to 4620 eV has been measured using the Nevada National Security Site Manson x-ray source. A broader range of energies was selected to compare results with previously published data. The measurements were taken using selected anodes, filters, and applied voltages to produce well-defined energy lines.
Degenerated Liouvillians and steady-state reduced density matrices
Authors: Thingna Juzar , Manzano Daniel
Published: July 2021

Symmetries in an open quantum system lead to degenerated Liouvillians that physically imply the existence of multiple steady states. In such cases, obtaining the initial condition independent steady states is highly nontrivial since any linear combination of the true asymptotic states, which may not necessarily be a density matrix, is also a valid asymptote for the Liouvillian. Thus, in this work, we consider different approaches to obtain the true steady states of a degenerated Liouvillian. In the ideal scenario, when the open system symmetry operators are known, we show how these can be used to obtain the invariant subspaces of the Liouvillian and hence the steady states. We then discuss two other approaches that do not require any knowledge of the symmetry operators. These could be powerful numerical tools to deal with quantum many-body complex open systems. The first approach that is based on Gram–Schmidt orthonormalization of density matrices allows us to obtain all the steady states, whereas the second one based on large deviations allows us to obtain the non-degenerated maximum and minimum current carrying states. We discuss the symmetry-decomposition and the orthonormalization methods with the help of an open para-benzene ring and examine interesting scenarios such as the dynamical restoration of Hamiltonian symmetries in the long-time limit and apply the method to study the eigenspacing statistics of the nonequilibrium steady state.
Ultra-sensitive lock-in amplifier coupled oscillatory magnetic tweezers for piconewton force manipulation applications
Authors: Wu Meiling , Lu H. Peter
Published: July 2021

We have developed lock-in amplifier coupled oscillatory magnetic tweezers, aiming to synchronize the oscillatory magnetic force application and single-molecule response detection at the applied oscillatory frequency by incorporating an optical lock-in amplifier detection. The designed home-built lock-in amplifier detection instrument enables an exact reference signal input and hence reveals an accurate and sensitive magnetic response synchronization. We have further demonstrated the approach with the rhodamine 6G stained super-paramagnetic beads by monitoring the below-the-noise-background weak fluorescence signal changes due to the magnetic response of the super-paramagnetic beads under the oscillatory force manipulation. The integration of the lock-in amplifier and the oscillating magnetic tweezers can significantly expand the application of the magnetic tweezers for signal detection below the noise background, such as adapting to the important applications in the detailed exploration of mechanical properties of biomolecules and studies of the protein conformational fluctuation dynamics.
Delineation of the flow and mixing induced by Rayleigh–Taylor instability through tracers
Authors: Zhang Ge , Xu Aiguo , Zhang Dejia , Li Yingjun , Lai Huilin , Hu Xiaomian
Published: July 2021

Rayleigh–Taylor-instability (RTI) induced flow and mixing are of great importance in both nature and engineering scenarios. To capture the underpinning physics, tracers are introduced to make a supplement to discrete Boltzmann simulation of compressible RTI flows. By marking two types of tracers with different colors, the tracer distribution provides a clear boundary of two fluids during the evolution. Fine structures of RTI flow and thermodynamic non-equilibrium behavior around the interface in a miscible two-fluid system are delineated. Distribution of tracers in their velocity phase space makes a charming pattern showing quite dense information on the flow behavior, which opens a new perspective for analyzing and accessing significantly deep insights into the flow system. RTI mixing is further investigated via tracer-defined local mixedness. The appearance of Kelvin–Helmholtz instability is quantitatively captured by the abrupt increase in mixedness averaged along the direction of acceleration. The role of compressibility and viscosity on mixing are investigated separately, both of which show a two-stage effect. The underlying mechanism of the two-stage effect is interpreted as the development of large structures at the initial stage and the generation of small structures at the late stage. At the late stage, for a fixed time, a saturation phenomenon of viscosity is found that a further increase in viscosity cannot lead to an evident decline in mixedness. The mixing statues of heavy and light fluids are not synchronous and the mixing of an RTI system is heterogeneous. The results are helpful for understanding the mechanism of flow and mixing induced by RTI.