bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Influence and Formation for Uncoordinated Deformation in Tram Subgrade
Authors: Cai Yang , Huang Chongwei , Chen Xi , Sun Yu , Guo Dandan
Published: December 2019

Aiming at horizontal and vertical uncoordinated deformation formation in Tram Subgrade, a 3D finite element model was established, which was used to analyse the mechanical response of tram monolithic roadbed on multiple depth and width of uncoordinated deformation. The results show that the uncoordinated deformation’s depth has little influence on the mechanical behavior of roadbed, and it indicates that there was remainder disengaging under the monolithic roadbed by the load of tram. On the other side, the width of uncoordinated deformation has a remarkable effect on outstanding to the horizontal tensile stress (σdy) in the slab bottom, deflection (Dd) on the top of slab, compressive stress (σsz) on the top of soil, and deflection (Dss) on the top of soil. The deflection on the top of subgrade surface is about 1.61mm. Therefore, the designer’s attention should be paid to avoid uncoordinated deformation width in the project, and avoid destroy of monolithic slab.
Research on strength detection and reinforcement technology of concrete building structures
Authors: Li Na , Yang Fangfang , Wang Dongli
Published: December 2019

Reinforced concrete is needed in houses, tunnels, garden facilities and so on. The first requirement for buildings is safety. Therefore, no matter what the design concept of buildings and how the structure of buildings changes, concrete as a basic material is indispensable, and it is particularly important to pay attention to the safety of reinforced concrete building structures. Thus, the reinforcement technology of reinforced concrete is derived. In this paper, the method of strength detection of concrete building structure is given first, and on this basis, the reinforcement technology of concrete and soil is deeply studied.
On Optimization and Adjustment of Road Line of Duozegou Bridge, the B Bid Section Road Project in the Upper Reaches of Ya-lung River
Authors: Wang Xiaolin , Yin Wei
Published: December 2019

Based on the external reconstruction project of B bid section road project in the upper reaches of Ya-lung River, this paper takes the total consideration of whole construction period control, construction risk, construction difficulty and investment saving of the Duozegou Bridge, and puts forward some optimization suggestions. From the aspects of the feasibility of the optimization, economic comparison and selection, this paper makes a deep discussion on the section of this road line, and obtains obvious results, which has won the great praise of the owner company. Meanwhile, this paper summarizes the experience for similar projects in the future, and provides reference for other similar projects at the same time.
Parameter analysis of stability bearing capacity of bottom frame beam for container building
Authors: Sun Songfeng , Guo Penggang , Zhang Qingyu , Chen Baoguang , Zhang Pingping
Published: December 2019

In this paper, the bottom frame beam of container building is analyzed by finite element method, and compared with the experimental results, the accuracy of the model is verified to meet the needs of the analysis. On this basis, by changing the stiffening position of the upper flange, the height of the web, the load layout and the thickness of the wall, the variation of the stability bearing capacity of the bottom frame beam was studied, the control factors affecting the stability bearing capacity of the bottom frame beam were obtained, and the selection suggestions were given.
Dynamic load test and load lateral distribution of box girder bridge in mining area under special load
Authors: Yuan Shengtao , Zheng Weilong , Chen Shunchao , Hu Chuanwen , Luo Wenbo , Xie Shoufu
Published: December 2019

Dynamic load test of bridge is one of the important indexes to evaluate bridge operation and bearing capacity, however, the test of the lateral distribution of bridge is one of the important means to evaluate the state of bridge. In order to evaluate the stress condition and working performance of a box girder bridge in a mining area under the special load of 100T, dynamic load test and lateral load distribution are studied, dynamic load test is to test the natural vibration frequency damping ratio and impact coefficient of the bridge through pulsating test and traffic running test, the transverse distribution of load is analyzed by deflection method and the experimental value of transverse distribution coefficient is compared with the theoretical value of girder method. The results show that under dynamic load, the first vertical natural vibration frequency of the bridge is 10.986, the damping ratio is 0.015%, and the impact coefficient is 1.07~1.26, the vertical measured fundamental frequency is larger than the calculated fundamental frequency, and the overall stiffness of the bridge meets with the design specification; the transverse connection among the box girders is close and the lateral distribution of load meets with the requirement of the design specification.
Study on the strength influence of pile driving disturbance on the surrounding soil
Authors: Li B.
Published: December 2019

The research on the strength influence of pile driving disturbance on the surrounding soil on marine environment is very less. This article is an actual pile driving project in the sea, the soil samplings with different distance from pile was taken and some laboratory test was done, the influence of soil property when pile driving is founded. According to the experimental results, the shear stress parameter and unconfined compressive strength index of soil in the hole increased with the increase of drilling depth, and the unconfined compressive strength index of soil in the hole nearly returned to the level of undisturbed soil 39 days after piling.
Application of temporary reinforcement technology in insufficient construction of the understructure bearing capacity of viaduct
Authors: Cao Guohui , Liu Reqiang , Liu Jing , Gao Xiang , Wang Peng
Published: December 2019

The complex three-dimensional traffic construction often occur when the lower structure cannot bear the construction load and other special cases, indicating the need for temporary reinforcement of the lower structure. In this paper, combined with a project construction example, various temporary reinforcement technologies are adopted to solve the insufficient bearing capacity during understructure construction, which poses a serious danger, to ensure synchronous construction of the understructure and viaduct. Compared with the traditional construction technology, the temporary reinforcement technology proposed in this paper features the advantages of saving project cost and time and has achieved better economic and social benefits.
A Study on Factors Influences Behaviour Intention towards Passenger Rail Transportation
Authors: Yoong Peng Chia , Pei Yee Tan , Min Yoong Ho
Published: December 2019

Environment concerns are developing trends as the number of private vehicles in Malaysia has expanded each and every year. The needs for effective and efficient public transportation services are crucial to attract more people to use public transport, hence overcoming the issue of traffic congestion. Rail as sustainable transport capable help in a decrease of private vehicles utilized and in addition accomplish green environment. The aim of this study is to determine the factor that influences behaviour intention towards rail transportation. All the predictor variables are involves in the study. The data were collected from 384 local peoples that stay in Klang Valley through questionnaire. The sampling method used in the study is non-probability. The outcomes of this study are expected encourage people to use the rail transportation services provided in Malaysia. In this study, attributes such as services reliability, fares, safety and security will be investigated to show the relationship between this variables and the behaviour intention of passenger on choosing rail transport. Data collected were then analysed using correlation and multiple regression analysis.
A study on the effectiveness of Personal Protective Equipment (PPE) on Building Construction Workers
Authors: Rong Guan Lu , Jun Xian Goh , Devi Rajendran Salini , Norida Wahab Siti
Published: December 2019

Nowadays, Occupational Safety and Health has getting more important in Malaysia. Personal Protective Equipment (PPE) is one of the way to protect building construction workers, PPE is any equipment, device or material that worn or used by the workers to protect them from exposure or contact with any harmful material which may cause injury, disease or even death. Despite its benefits, the awareness of PPE is low among building construction workers. The purpose of this study is to examine the utilization of PPE and how the knowledge of using PPE affecting the safety of the workers on building construction. There are 100 workers from the building construction industry who participated in the survey. The data were collected using self-designed questionnaires and analyzed using partial correlation and multiple regression analysis. The obtained result reveals that awareness and training have positive effect while experience has negative effect toward the effectiveness on PPE on the construction workers.
A study on Passengers Perspective towards in-flight food delivery and waste collection services
Authors: Mei Shin Koh , Kin Hon Yip , Devi Rajendran Salini
Published: December 2019

The quality of the direct airline services especially food delivery and waste collection services can affect the passenger’s impression toward the airlines. This study mainly focuses on determine Malaysian passengers’ characteristics in selecting flight services and identifying the perception of Malaysian passengers regarding in-flight food delivery service performance. The data was gathered through questionnaires from 405 Malaysian passengers from Malaysia's main international airport, Kuala Lumpur International Airport (KLIA). Software of IBM SPSS version 22 is used to analyze the collected data. This study contributes the knowledge on Malaysian passenger’s opinion regarding in-flight food delivery service and explores the areas that need for improvement. The findings of this result could be considered for the airline companies which trying figure out a way to maintain and improve quality of in-flight food service.
Study on learning landscape outdoor space of primary school campus based on Permaculture and symbiotic theory——Hefei Experimental School as an example
Authors: Shaojie Zhang , Limin Yin , Yunle Zhang , Shuhan Zheng , Tong Zhang
Published: December 2019

With the study of the relevant literatures and applications of Permaculture and symbiotic theory, this paper deeply explores its theoretical significance for the outdoor learning landscape planning and design of modern primary schools. We provide a fuller and more realistic understanding on the outdoor landscape of the campus that adapts to the growth and development of children in primary school，so as to find a practical reference for the outdoor learning landscape construction of primary school campus that plays the greatest role of natural education.
Dynamic coupling law of ecological support capacity and economic social development in Anhui Province from 2000 to 2015
Authors: Jiao Lifeng , Gao Yalun , Pan Hairu , Chen Guangzhou
Published: December 2019

By selecting the typical indicators of ecological supporting capability and economic social development to construct the index system, the levels of ecological supporting capability and economic social development in Anhui province from 2000 to 2015 were calculated based on the method of principal component analysis. Then, the scissors difference method was employed to study their dynamic relationship. The results showed that the ecological support ability in Anhui province increased rapidly first and then slowly; and economic social development increased exponentially. Its coupling and coordination degree changed from a serious recession to a well-coordinated development. Through the analysis of the fitting equation and scissors difference, it revealed their interaction law, and provided decision support for the scientific, sustainable development of Anhui province.
Air Pollutants Prediction in Shenzhen Based on ARIMA and Prophet Method
Authors: Ye Ziyuan
Published: December 2019

In order to improve the accuracy of predicting the air pollutants in Shenzhen, a hybrid model based on ARIMA (Autoregressive Integrated Moving Average model) and prophet for mixing time and space relationships was proposed. First, ARIMA and Prophet method were applied to train the data from 11 air quality monitoring stations and gave them different weights. Then, finished the calculation about weight of impact in each air quality monitoring station to final results. Finally, built up the hybrid model and did the error evaluation. The result of the experiments illustrated that this hybrid method can improve the air pollutants prediction in Shenzhen.
Comparisons on Calculating Methods of Total Daily Global Solar Radiation in Urban Area Based on Panoramic Images
Authors: Zhang Moyan , Liu Yan , Chen Ruixin , Guo Xiangfei , Yuan Weiqing , Yang Liu
Published: December 2019

In this paper, the total daily global solar radiation is tested at 18 locations with different morphological characteristics in Xi’an University of Architecture and Technology. PTgui is used to convert the panoramic pictures from Baidu Street Map to fisheye images. Sky view factor (SVF) and tree view factor (TVF) are calculated by Rayman model with fisheye images. SVF is used to calculate the total daily global solar radiation at the 18 locations with two different methods and TVF is used to classify the locations. The calculations and testing results are compared and combined the morphological characteristics. Then it is found that using suitable methods on different locations is necessary to obtain more accurate results whether the TVF (tree view factor) is more than 0.3 or less. To obtain solar radiation at different locations in the urban area, the calculating methods should be carefully chosen based on the morphology characteristics of the location.
Research on Calculation Method of Total Solar Radiation of Urban Settlements Based on Parametric 3D Model
Authors: Chen Ruixin , Liu Yan , Zhang Moyan , Li Qi , Zhang Hao , Yang Liu
Published: December 2019

Solar radiation is a major factor in promoting the sustainable development of urban settlements. To understand the distribution of solar radiation in urban settlements, this paper develops the sky view factor (SVF) algorithm based on the parameterization platform to simplify the calculation of solar radiation. In this paper, the test of total solar radiation is carried out in 18 different locations in Xi'an University of Architecture and Technology. The total solar radiation of 18 points is calculated using the SVF-based calculation model. Comparing the calculated results with the measured results, it is found that the calculated values are consistent with the measured values. The results show that the algorithm is consistent with the measured data. It shows the effectiveness and high precision of the proposed algorithm. The algorithm can calculate the total solar radiation more quickly, and provide technical support for urban preliminary design schemes in urban microclimate.
Effects of Chitosan on Soluble Sugar Content in Prunus davidiana Seedlings
Authors: Sun Jing , Li Aihui , Jing Qianhe , Huang Yingying , Han Jiaxi , Lin Lijin
Published: December 2019

A pot experiment was conducted to study the effects of different concentrations of chitosan solutions (0, 1, 2, 4, 6 g/L) on soluble sugar content in Prunus davidiana seedlings. The result showed that there was no significant difference of the soluble sugar content in roots, stems, leaves and shoot in P. davidiana seedlings between at 1 g/L concentration and the control. All concentration treatments were reduced the soluble sugar content in roots and stems of P. davidiana seedlings compared with the control. On the contrary, all concentration treatments were improved the soluble sugar content in leaves and shoot of P. davidiana seedlings compared with the control and the concentration treatment of 2 g/L and 4 g/L was at a higher level. All concentration treatments were improved the content in relative conductivity of blade in P. davidiana seedlings and the concentration treatment of 4 g/L was at a higher level. On the contrary, all concentration treatments were reduced the content in soil conductivity. Therefore, the chitosan solutions concentration of 2 g/L and 4 g/L concentration was beneficial to soluble sugar content in P. davidiana seedlings. On the contrary, high concentration of chitosan solutions was not good for soluble sugar content.
Effects of Different Iron Concentrations on Physiology of Prunus davidiana Seedlings
Authors: Yang Liu , Zheng Bixia , Zhang Xiao , Cui Tonghao , Xia Xianmin , Liao Ming’an
Published: December 2019

In order to study the changes of the photosynthetic pigment content, antioxidant enzyme activity and osmotic adjuster content, the Prunus davidiana seedlings were cultured into Hoagland nutrient solution which added various concentrations of iron solution. Then the results showed that photosynthetic pigment content and antioxidant enzyme activity were all higher in iron-treated P. davidiana seedlings, compared with that in control seedlings. When increased iron concentration up to 10 mg/L, the chlorophyll a, chlorophyll b and the total chlorophyll content gradually rose, but decreased at iron concentrations of 20, 30, 40 and 60 mg/L. Irrigating iron concentration of 60 mg/L was the best way to increase the activity of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), and malondialdehyde (MDA) content. But for chlorophyll a/b ratio, it was the highest in no-iron seedlings. Moreover, the soluble protein content was the highest at iron concentration of 30 mg/L, but the lowest at 10 mg/L. Thus, the study concluded that irrigating iron solution could improve the growth and resistance to adverse circumstances of P. davidiana seedlings.
Effects of Different Selenium Concentrations on Physiology of Prunus davidiana Seedlings
Authors: Yang Liu , Li Qinyuan , Shu Junjiang , Xiao Ling , Gao Xinyu , Liao Ming’an
Published: December 2019

To study the effects of selenium on physiology, Prunus davidiana seedlings were treated with the irrigation of different selenium concentrations solution. The result showed that the photosynthetic pigment content was relatively higher at selenium concentrations of 0, 0.05 and 0.1 mg/L except for carotenoid content which was the highest at 0.1 mg/L but the lowest in control seedlings. In terms of antioxidant enzyme activity, the activities of peroxidase (POD), catalase (CAT) and superoxide dismutase (SOD) in selenium-treated seedlings were all higher than that in control seedlings and especially at the selenium concentration of 1 mg/L. The soluble protein content accumulated most at 0.25 mg/L selenium concentration. The content of malondialdehyde (MDA), as membrane lipid peroxidation index, was the lowest at selenium concentration of 0.5 mg/L. In a word, irrigating lower selenium concentrations could increase the photosynthetic pigment content and higher selenium concentrations enhanced the antioxidant enzyme activity to increase cell protection and kept the P. davidiana seedlings good growth and resistance to adverse environments.
Effects of exogenous indole-3-acetic acid on the photosynthesis characteristics of lettuce under cadmium stress
Authors: Sun Guochao , Wang Yan , Wei Xiaohan , Xiao Yunying , Xu Xiangting , Tang Yi
Published: December 2019

IAA (indole-3-acetic acid), can regulate plant growth and development, and it can involve in regulation of abiotic stresses. In the present study, the effects of spraying different concentrations (0, 25, 50, 100 and 200 μmol/L) of IAA on the photosynthesis physiology in lettuce were investigated. The lettuce (Lactuca sativa) exposed to cadmium (Cd) exhibited a substantial change in photosynthetic pigment content and photosynthetic parameters. Spraying exogenous IAA resulted in alleviating the inhibitory of Cd toxicity to lettuce. The photosynthetic pigment content in shoot of lettuce increased by spraying with IAA compared with the Cd treatment alone. Cd stress caused reductions (P < 0.05) in Pn and Ls, respectively, whereas Gs, Ci, and Tr were increased, compared with the control. Spraying exogenous IAA resulted that the Pn increased and the Ls, Gs, Ci, Tr showed different trend. Therefore, spraying IAA effectively changed the photosynthetic pigment contents and photosynthesis parameters in lettuce.
Study on the selenium accumulation of peach seedlings
Authors: Wu Caifang , Dong Yiping , Chen Xu , Bie Yuhui , Hou Yuefeng , Lin Lijin
Published: December 2019

An experiment was conducted to study the effect of peach seedlings (Prunus davidiana) grown in nutrient solution with different selenium concentration. The results showed that selenium concentration were 0.05 and 0.10 mg/L which caused a marked increase of roots and shoorts biomass, and the root/shoot ratio were relatively low (0.180 and 0.170) compared with control, and other selenium treatments decreased significantly the biomass. Consequently, 0.05 and 0.10 mg/L selenium treatments were conducive to peach seedlings growth, while the peach seedlings was inhibited significantly by the increasing concentration of selenium (≥ 0.10 mg/L). Selenium content of peach seedlings increased remarkably with the increase of selenium concentration that indicated the accumulation of selenium in peach seedlings had a linear relation with the dose of selenium. Above all, when selenium concentration in the range of 0-0.10 mg/ L, which not only promotes peach seedlings growth, but also increases peach seedlings selenium content.
Spatial Variability Analysis of Farmland Soil Infiltration Based on Model Parameters
Authors: Xin Qingdao , Zhu Hemin , Wang Yangren , Fan Xinrui
Published: December 2019

Research on the variation of soil infiltration is helpful to analyze the mechanism of soil water movement in farmland. At the same time, soil infiltration characteristics affect the surface irrigation. Based on the field test data, this study simulated and analyzed the soil infiltration with three soil infiltration models (Kostiakov-Lewis model, Philip model and Horton model). The infiltration uncertainty of farmland soil are investigated, and proposed by using two random simulation methods (direct method and parameter mean method) of infiltration. The evaluated indicators are the interval size and its stability of cumulative infiltration amount changed with 95% confidence. The effects of different random simulations methods and three models on the infiltration process are compared and analyzed. Finally, the model and stochastic simulation method suitable for the infiltration characteristics of the farmland are determined. The results show that the correlation coefficients of the three models are all above 0.98, and there is no significant difference in fitting accuracy. In terms of the degree of spatial uncertainty (determined by standard deviation): direct method > parameter mean method, in which the combination of the Kostiakov-Lewis model and the parameter mean method have less uncertainty, and the combined simulation effect is better, it is more suitable for the simulation of soil infiltration at farmland scale.
Morphological diversity of the stone crayfish − traditional and geometric morphometric approach
Authors: Lovrenčić Leona , Pavić Vjera , Majnarić Stefan , Abramović Lucija , Jelić Mišel , Maguire Ivana
Published: December 2019

Austropotamobius torrentium is one of four native European crayfish species inhabiting Croatian freshwaters. Existence of eight divergent monophyletic mtDNA phylogroups was described within A. torrentium; six of them are distributed in Croatia, with the highest genetic diversity established in its northern-central Dinaric region. Recent small-scale study of the stone crayfish morphological variability indicated significant differences among different phylogroups. In the present study larger sample size, covering populations from five phylogroups, was analysed with the aim of determining whether there are morphological characteristics that reliably separate stone crayfish from different phylogroups. Aiming this, 245 stone crayfish were analysed through traditional (TM) and, for the first time, geometric morphometric (GM) analyses. Multivariate discriminant analyses included 24 TM characteristics per crayfish, while GM comprised analyses of 22 landmarks on the dorsal side of cephalon. Both methods revealed congruent results, and significant differences among phylogroups in analysed features were obtained, with the cephalon shape contributing the most to crayfish discrimination. Research confirmed that both approaches, combined with statistical methods, are useful in distinguishing and separating crayfish phylogroups. Findings of present study are compatible with the previous molecular findings; stone crayfish present several distinct evolutionary lineages whose species status are currently undefined and require urgent clarification.
Optimal strategies and pricing analysis in M/M/1 queues with a single working vacation and multiple vacations
Authors: Tian Ruiling , Wang Yali
Published: December 2019

This paper considers the customers’ equilibrium and socially optimal joining-balking behavior in single-server Markovian queues with a single working vacation and multiple vacations. Arriving customers decide whether to join the system or balk based on the system states and a linear reward-cost structure, which incorporates the desire of customers for service and their dislike to wait. We consider that the system states are almost unobservable and fully unobservable, respectively. For these two cases, we first analyze the stationary behavior of the system, and get the equilibrium strategies of the customers and compare them to socially optimal balking strategies using numerical examples. We also study the pricing problem that maximizes the server’s profit and derive the optimal pricing strategy. Finally, the social benefits of the almost and fully unobservable queues are compared by numerical examples.
The GOES-R EUVS model for EUV irradiance variability
Authors: Thiemann Edward M. B. , Eparvier Francis G. , Woodraska Don , Chamberlin Phillip C. , Machol Janet , Eden Thomas , Jones Andrew R. , Meisner Randy , Mueller Steven , Snow Martin , Viereck Rodney , Woods Thomas N.
Published: December 2019

The Geostationary Operational Environmental Satellite R (GOES-R) series of four satellites are the next generation NOAA GOES satellites. Once on orbit and commissioned, they are renamed GOES 16–19, making critical terrestrial and space weather measurements through 2035. GOES 16 and 17 are currently on orbit, having been launched in 2016 and 2018, respectively. The GOES-R satellites include the Extreme Ultraviolet (EUV) and X-ray Irradiance Sensors (EXIS) instrument suite, which measures calibrated solar irradiance in eight lines or bands between 25 nm and 285 nm with the Extreme Ultraviolet Sensors (EUVS) instrument. EXIS also includes the X-Ray Sensor (XRS) instrument, which measures solar soft X-ray irradiance at the legacy GOES bands. The EUVS Measurements are used as inputs to the EUVS Model, a solar spectral irradiance model for space weather operations that predicts irradiance in twenty-two 5 nm wide intervals from 5 nm to 115 nm, and one 10 nm wide interval from 117 to 127 nm at 30 s cadence. Once fully operational, NOAA will distribute the EUVS Model irradiance with 1 min latency as a primary space weather data product, ushering in a new era of rapid dissemination and measurement continuity of EUV irradiance spectra. This paper describes the EUVS Model algorithms, data sources, calibration methods and associated uncertainties. Typical model (relative) uncertainties are less than ~5% for variability at time-scales longer than 6 h, and are ~25% for solar flare induced variability. The absolute uncertainties, originating from the instruments used to calibrate the EUVS Model, are ~10%. Examples of model results are presented at both sub-daily and multi-year timescales to demonstrate the model’s capabilities and limitations. Example solar flare irradiances are also modeled.
Novel hemostatic adhesive powder for nonvariceal upper gastrointestinal bleeding
Authors: Park Jin-Seok , Kim Hyung Kil , Shin Yong Woon , Kwon Kye Sook , Lee Don Haeng
Published: December 2019

Background and study aims A new hemostatic adhesive powder (UI-EWD) was developed to reduce high rebleeding rates and technical challenges associated with application of currently available hemostatic powders. The aim of the current study was to assess performance of UI-EWD for nonvariceal upper gastrointestinal bleeding (NVUGIB).

Patients and methods A total of 56 consecutive patients that received UI-EWD monotherapy for endoscopic hemostasis due to NVUGIB were retrospectively reviewed. Main study outcomes were success rates with immediate hemostasis and rebleeding within 30 days. Outcomes were analyzed by reviewing patient medical records.

Results Etiologies of bleeding were: post-endoscopic therapy bleeding in 46 (82.1 %), peptic ulcer in 8 (14.3 %), tumor in 1 (1.8 %), and other in 1 (1.8 %). UI-EWD was successfully applied at bleeding site in all cases. The success rate of immediate hemostasis was 96.4 % (54/56), and the 30-day rebleeding rate among patients that achieved immediate hemostasis was 3.7 % (2/54). No adverse event related to use of UI-EWD occurred.

Conclusion UI-EWD was found to have a high immediate hemostasis success rate in NVUGIB when used as monotherapy and showed promising results in terms of preventing rebleeding.
Gefäßmedizin in der Zukunft – Möglichkeiten mit 3D-Druckverfahren
Authors: Dorweiler Bernhard , El Beyrouti Hazem , Vahl Christian Friedrich , Baqué Pia-Elisabeth , Ghazy Ahmed
Published: December 2019

Die Digitalisierung der Chirurgie ist eine der richtungsweisenden Herausforderungen der aktuellen und kommenden Chirurgengenerationen. Für das Gebiet der Gefäßmedizin steht mit dem 3D-Druck eine digitale Technologie zur Verfügung, deren Implementierungsmöglichkeit interessante Perspektiven bietet und evaluiert werden muss. Die 3D-Drucktechnologie erlaubt neben dem Einsatz zu Aufklärungs-, Trainings- und Simulationszwecken auch die Herstellung von patientenindividuellen OP-Schablonen und Implantaten. In unserer Klinik wird diese Technologie derzeit in den Bereichen Operationsplanung bei komplexer Gefäßmorphologie, Patientenaufklärung und zu Trainingszwecken verwendet. Die aktuellen industriellen Weiterentwicklungen hinsichtlich Softwarelösungen, Materialpalette und Druckereigenschaften lassen eine deutliche Vereinfachung des Herstellungsprozesses von patientenindividuellen 3D-Modellen und eine Expansion der Anwendungsmöglichkeiten erwarten.
Therapeutischer Aufwand in stationärer oder tagesklinischer
Behandlung und Therapieerfolg bei Patienten mit depressiven
Störungen
Authors: von Wietersheim Jörn , Knoblauch Jamie Dwayne , Rottler Edit , Weiß Heinz , Hartmann Armin , Rochlitz Peter , Völker Alexander , Scheidt Carl Eduard , Beutel Manfred E. , Eckhardt-Henn Annegret , Zeeck Almut
Published: December 2019

Während einer stationären oder tagesklinischen
psychosomatische Behandlung finden unterschiedliche therapeutische
Maßnahmen wie Einzelpsychotherapie, Gruppentherapie, kreative
Therapien sowie Gespräche mit den Pflegekräften statt. Die
durchgeführten Therapien müssen als OPS-Codes dokumentiert
und dem Institut für das Entgeltsystem im Krankenhaus (INeK)
mitgeteilt werden. Mit den Daten der INDDEP-Studie sollten die OPS-codierten
Therapien aus 7 Kliniken und 8 Tageskliniken verglichen werden. Weiter
sollte untersucht werden, ob die per OPS dokumentierte therapeutische Dosis
einen Einfluss auf den Therapieerfolg hat. In der Studie wurden die Daten
von Patienten mit depressiven Störungen an 4 Messzeitpunkten
(Aufnahme, Entlassung, 3 Monate und 12 Monate nach Entlassung) erhoben,
zudem wurden die OPS-Codes der Behandlungen dokumentiert. Insgesamt konnten
die Daten von 577 Patienten aus 8 Zentren ausgewertet werden. Es zeigte
sich, dass über die OPS-Codes eine grobe Erfassung der Therapiedosis
möglich ist. Die Kliniken unterscheiden sich signifikant
hinsichtlich der Intensität und berufsgruppenspezifischen
Zusammensetzung der kodierten therapeutischen Maßnahmen, das gilt
sowohl für die stationären wie auch die tagesklinischen
Behandlungen. Die dokumentierte wöchentliche Therapiedosis in den
Tageskliniken liegt etwas niedriger als die der stationären
Behandlungen. Es zeigte sich kein statistischer signifikanter Zusammenhang
zwischen der Gesamttherapiedosis und einer Verbesserung der depressiven
Symptomatik. Es sind patienten-, therapie- oder prozessbezogene Variablen zu
vermuten, die einen solchen Zusammenhang moderieren. Diese müssten
in weiteren Studien identifiziert werden.
Synthesis of Bis-BINOL Derivatives: Linking via the 3-, 4-, or 5-Position by Generation of Suitable C
1-Symmetric Precursors
Authors: Kohlhaas Martha , Lutz Fabian , Paransothy Nirtharsan , Octa-Smolin Frescilia , Wölper Christoph , Niemeyer Jochen
Published: December 2019

Bis-BINOL derivatives have proven highly useful in applications such as chemosensing or organocatalysis. In this account, we describe strategies for the linking of BINOL units via the 3-, 4-, or 5-positions, showing that unique synthetic strategies are necessary to address each position. We report the synthesis of suitable C
1-symmetric precursors, which are generated either by monohalogenation or by monodeprotection of C
2-symmetric starting materials, and their subsequent coupling to give linked bis-BINOL derivatives.
Ligadura de fuga venosa dorsal profunda en pene: Revisión de la literatura y técnica quirúrgica paso a paso
Authors: Arcila Juan Fernando Uribe
Published: December 2019

La disfunción venoclusiva peneana (VOD), está siendo reconocida como una causa importante de disfunción eréctil en especial en pacientes jóvenes. Recientemente se han sugerido fisiopatologías novedosas y se han mejorado notablemente los métodos diagnósticos, lo que genera un campo en redescubrimiento con nuevos enfoques de tratamiento disponibles. La ligadura de fuga venosa dorsal ha tenido dificultades a través de la historia para ser estandarizada. El artículo enfatiza que el diagnóstico adecuado es la base del éxito en esa patología, para cuya resolución presentamos una técnica quirúrgica asequible, aún en sitios con limitaciones tecnológicas, reproducible y con buenos resultados a corto y mediano plazo. Cuando se sospecha de una fuga venosa dorsal profunda que cause alteraciones hemodinámicas con un cierto tipo de disfunción eréctil, con penes que en erección alternan en estados de duro-blando, se configura un síndrome especial, con hallazgos clínicos y ecográficos típicos. Aunque existen algunas opciones médicas de tratamiento, se propone la corrección quirúrgica de la fuga venosa como el método ideal de tratamiento definitivo.
Transparent Tubular Retractor in Cranial Surgery: A Retrospective Analysis
Authors: Shashivadhanan Sundaravadhanan
Published: December 2019

Introduction The fourth Industrial Revolution has touched nearly all aspects of neurosurgery and the newer tubular retractor systems are a testimony to this fact. They aid in providing better visualization with minimal damage to those neural structures, which happen to be innocent bystanders overlying the path of deep-seated lesions. In addition to providing better patient outcomes they are surgeon friendly with their ergonomic design and improved stability, thereby causing minimal fatigue, and aid in procedures requiring precision and perseverance. A retrospective study conducted at a single institute analyzed the efficacy of transparent tubular retractors during cranial surgery for deep-seated lesions.

Materials and Methods This retrospective study was conducted between April 2015 and July 2018 in a single institute wherein 22 patents with various deep-seated intracranial lesions were operated using the transparent tubular retractor, View Site Brain Access System (VBAS, Vycor Medical Inc.).

Observation Of the 22 cases, 45% were of spontaneous intracerebral hemorrhage; 27% were high-grade gliomas; and the rest were colloid cyst, cystic tumors, and metastatic tumors in equal proportion. Total tumor excision was achieved in 27%, while 90% excision was achieved in 45% cases. The overall complication rate was 13%.

Conclusion The transparent tubular retractors contribute to minimal invasiveness by causing uniform distribution of retraction pressure and minimal disruption of fiber tracts. Their use has a definite role in improving surgical outcomes for deep-seated intracranial lesions.
The Effects of Patient Occupation, Hobbies, and Body Mass Index on Kneeling after Total Knee Arthroplasty
Authors: Sabeh Karim G. , Hernandez Victor H. , Cohen-Levy Wayne B. , Ong Alvin , Orozco Fabio , Bennett Veronica , Post Zachary
Published: December 2019

A common patient concern after total knee arthroplasty (TKA) is the ability to kneel. Kneeling may have a substantial impact on the patients' ability to perform many activities of daily living, occupations, and hobbies. The purpose of this study was to quantify the percentage of patients able to kneel after TKA after 2 years and to evaluate preoperative patient characteristics that influence the patient's perceived ability to kneel after TKA such as obesity, occupation, and hobbies. We retrospectively assessed a cohort of 404 patients who underwent primary TKA with patellar resurfacing. We assessed the impact of patient hobbies, occupation, employment status, and body mass index (BMI) on the kneeling capacity and patient-reported satisfaction. Univariate analysis was performed using Fisher's exact test, and multivariate analysis was performed using logistic regression with multiple imputations. A total of 404 patients were included. Sixty percent of patients were unable to kneel after TKA. Males (p < 0.001) and patients with occupations or hobbies requiring kneeling (p < 0.05) were more likely to kneel after surgery. We identified an inverse relationship between BMI and the ability to kneel. No correlation was found between duration and frequency of kneeling relative to patient-reported ease or difficulty with kneeling. Patient-reported factors that prevented patients from kneeling were pain, physical inability, and fear of damaging the prosthesis. Patient education may be helpful in improving patient expectations about kneeling after surgery. A small but significant difference in subjective patient satisfaction was observed when comparing patients able to kneel with those unable to kneel.
A novel electro-active bushing based on dielectric elastomer and circular double-V auxetic structure
Authors: Wang Yuanlong , Yu Yi , Li Zhen , Wang Chunyan , Zhao Wanzhong
Published: December 2019

A novel electro-active bushing (EAB) design is proposed based on the unique physical properties of dielectric elastomers. A dielectric elastomer is applied as the tendon layer to a circular two-dimensional double-V auxetic structure. When load and voltage excitation vary, mechanical performance and dimensions of dielectric elastomers change, which empowers EAB to realize an electrostrictive phenomenon and real-time variable stiffness under different voltages. An EAB structure can endure mechanical loads along all directions in a cross-sectional plane, which is more practical than our previous design which can only bear loads along one direction. A theoretical electromechanical model of an EAB unit cell was proposed based on the physics theory of dielectric elastomers. The influences of unit cell parameters on electromechanical responses were researched. Moreover, an EAB prototype was fabricated via the 3D printing method. The experiments using EAB prototype applied 3M VHB 4910 and 3M VHB 9473 acrylic membranes prestretched by 200% and 300%, respectively, were conducted. The results indicated that the electrostrictive displacement increases as the load increases, and the stiffness decreases with the rise in voltage. Greater stiffness is obtained by higher original thickness and prestretch rates, but the electrostrictive displacement and stiffness variation under high excitation was dramatically affected.
Probing the origins of electroresistance switching behavior in ferroelectric thin films
Authors: Ren Zhong-Qi , Liu Yan-Dong , Bao Si-Yao , Yang Nan , Zhong Ni , Tang Xiao-Dong , Xiang Ping-Hua , Duan Chun-Gang
Published: December 2019

Ferroelectric thin films have been systematically investigated via scanning probe microscopy in recent years. Research indicates that the surface potential is the combined result of injected and polarization charges. The relationships between surface potentials and the two types of charges are usually investigated via scanning Kelvin probe microscopy (SKPM). Typically, SKPM investigations indicate that the surface charge distribution is dominated by injected charges trapped during poling using a conductive AFM tip rather than by polarization charges. The presence of injected charges leads to controversy concerning the origins of resistive switching behavior. In this study, relaxation of injected charges was observed during an optimized thermal treatment. This caused polarization charges to dominate over injected charges. Different electroresistance switching characterizations were observed via conductive atomic force microscopy (C-AFM) of injected and polarization charge-dominated films. Our research extends the methods of distinguishing whether electroresistance switching behavior is driven by charge trapping/detrapping or ferroelectric polarization. This provides an effective approach to classifying the origins of electroresistance switching in ferroelectric thin films by combining piezoelectric force microscopy, SKPM, and C-AFM.
Ballistic hot-electron transport in a quantum Hall edge channel defined by a double gate
Authors: Akiyama Shunya , Hirasawa Taichi , Sato Yuya , Akiho Takafumi , Muraki Koji , Fujisawa Toshimasa
Published: December 2019

Ballistic transport of hot electrons in a quantum Hall edge channel is attractive for studying the electronic analog of quantum optics, where the edge potential profile is an important parameter that governs the charge velocity and scattering by longitudinal-optical (LO) phonons. Here, we use a parallel double gate to control the electric field of the edge potential and investigate the ballistic length of the channel by using hot-electron spectroscopy. The ballistic length is significantly enhanced by reducing the LO phonon scattering rate in the tailored potential.
Temperature dependent switching of magnetoresistance in multiwall carbon nanotube-polypyrrole composite fibrils
Authors: Rani Reena , Sharma Meenu , Rani Sonam , Shankar Aditi , Prasad V. , Boi Filippo S. , Sameera I. , Bhatia Ravi
Published: December 2019

Carbon nanotubes (CNT) are considered one of the most significant materials in nanoelectronic device applications because they can be used in the fabrication of both CNT-inorganic hybrid structures and CNT-organic composite materials. Also, the study of the electrical properties of these materials has its own fundamental and technological significance. Here, we report on low temperature charge transport characteristics (down to 4.2 K in the magnetic fields up to 11 T) of multiwall carbon nanotube (MWCNT)-polypyrrole (PPy) coaxial composite fibrils synthesized by a facile electrochemical polymerization method. Two types of samples were synthesized by carrying out electrochemical polymerization at room temperature (RT) for different durations of 90 and 45 min, respectively. Scanning electron microscopy studies indicated that the diameters of as-prepared MWCNT-PPy fibril samples were ∼1.5 μm and 0.5 μm, respectively. The dc electrical resistance of the two samples was ∼103 and 102 Ω at RT and exhibited a pronounced temperature dependence, which is indicative of the hopping process being dominant. Furthermore, a large positive magnetoresistance (MR) of ∼29% and ∼18% is displayed at 4.2 K, which switched to negative MR with a maximum magnitude of ∼11% and ∼15% at 10 K for the two samples, respectively. The switching of MR as a function of temperature showed the dominance of two important competing phenomena, namely, wave function shrinkage and forward interference of electron waves.
Correlative study of structural and optical properties of ZnSe under severe plastic deformation
Authors: Sotillo B. , Escalante G. , Radoi C. , Muñoz-Sanjosé V. , Piqueras J. , Fernández P.
Published: December 2019

The effect of plastic deformation on the optical and structural properties of ZnSe crystals has been investigated. The optical properties have been monitored by cathodoluminescence measurements as a function of the deformation degree. Remarkable differences in the defect-related emissions from the most severely deformed areas have been encountered. Deformation of the crystal lattice of ZnSe, associated with slip phenomena, has been studied by means of Electron Backscattered Diffraction and micro-Raman spectroscopy. The relation between the deformation and the optical properties of the ZnSe crystals has been described.
High-pressure melt curve of shock-compressed tin measured using pyrometry and reflectance techniques
Authors: La Lone B. M. , Asimow P. D. , Fat’yanov O. V. , Hixson R. S. , Stevens G. D. , Turley W. D. , Veeser L. R.
Published: December 2019

We have developed a new technique to measure the melt curve of a shocked metal sample and have used it to measure the high-pressure solid-liquid phase boundary of tin from 10 to 30 GPa and 1000 to 1800 K. Tin was shock compressed by plate impact using a single-stage powder gun, and we made accurate, time-resolved radiance, reflectance, and velocimetry measurements at the interface of the tin sample and a lithium fluoride window. From these measurements, we determined temperature and pressure at the interface vs time. We then converted these data to temperature vs pressure curves and plotted them on the tin phase diagram. The tin sample was initially shocked into the high-pressure solid γ phase, and a subsequent release wave originating from the back of the impactor lowered the pressure at the interface along a constant entropy path (release isentrope). When the release isentrope reaches the solid-liquid phase boundary, melt begins and the isentrope follows the phase boundary to low pressure. The onset of melt is identified by a significant change in the slope of the temperature-pressure release isentrope. Following the onset of melt, we obtain a continuous and highly accurate melt curve measurement. The technique allows a measurement along the melt curve with a single radiance and reflectance experiment. The measured temperature data are compared to the published equation of state calculations. Our data agree well with some but not all of the published melt curve calculations, demonstrating that this technique has sufficient accuracy to assess the validity of a given equation of state model.