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Underground Space 2017年第2期2卷 115-124页

作者： morgen R.Leake William J.Conrad erik C.Westman Setareh Ghaychi Afrouz Ryan J.molka mining and minerals Engineering Department Virginia Polytechnic Institute and State University445 Old Turner Street100 Holden HallBlacksburgVA 24060USA

A microseismic monitoring system was installed in an underground room and pillar coal mine in the Eastern United States to analyze the occurrence and characteristics of induced seismicity during the retreat of two panels in the *** study is the first microseismic monitoring effort at an underground coal mine in nearly 30 *** the retreat of the first panel,an array of eight uniaxial geophones,installed 10 *** the roof,recorded events and their *** second panel was monitored using an array of twelve uniaxial geophones and two triaxial geophones,also installed 10 *** the *** the results of these studies,it has been found that the magnitude of seismic events is minimally affected by immediate roof geology or depth of ***,it was observed in both studies that the rate at which seismic events occurred did vary with changing roof geology and depth of *** the seismic data from the second panel retreat,focal mechanism solutions were generated for 50 hand-picked events in order to determine if the failure was in compression,tension,or *** of the focal mechanism solutions show that stress relief resulting in dilational events occurs at significant depths,150-200 m in this case,beneath the active mining face.

关键词： Deep mining Induced seismicity Coal mining Rock mechanics Source mechanisms Subsidence

Changes in Barents Sea ice Edge Positions in the Last 440 years: A Review of Possible Driving Forces

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International Journal of Astronomy and Astrophysics 2020年第2期10卷 97-164页

作者： Nils-Axel m&ouml rner Jan-erik Solheim Ole Humlum Stig Falk-Petersen Paleogeophysics & Geodynamics Stockholm Sweden Department of Physics and Technology UiT The Arctic University of Norway Troms&oslash Norway The University Centre on Svalbard (UNIS) Longyearbyen Svalbard Norway The Fram Centre Akvaplan-niva Troms&oslash Norway

This is the first report of the Barents Sea Ice Edge (BIE) project. The BIE position has varied between latitude 76°N and above 82°N during the last 440 years. During the period 10,000 to 6000 years ago, Arctic climate was significantly warmer than today. We review various oceanic and atmospheric factors that may have an effect on the BIE position. The Gulf Stream beat with respect to alternations in flow intensity and N-S distribution plays a central role for the changes in climate and BIE position during the last millennium. This occurred in combination with external forcing from total solar irradiation, Earth’s shielding strength, Earth’s geomagnetic field intensity, Earth’s rotation, jet stream changes;all factors of which are ultimately driven by the planetary beat on the Sun, the Earth and the Earth-moon system. During the last 20 years, we see signs of changes and shifts that may signal the end of the late 20th century warm period. The BIE position is likely to start advancing southward in next decade.

关键词： Barents Sea Ice Edge Cyclic Changes Gulf Stream Beat Planetary-Solar Forcing

Changes in Barents Sea Ice Edge Positions in the Last 442 Years. Part 2: Sun, moon and Planets

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International Journal of Astronomy and Astrophysics 2021年第2期11卷 279-341页

作者： Jan-erik Solheim Stig Falk-Petersen Ole Humlum Nils-Axel m&ouml rner Retired Department of Physics and Technology UiT The Arctic University of Norway Troms&oslash Norway Akvaplan-niva The Fram Centre Troms&oslash Norway The University Centre on Svalbard (UNIS) Longyearbyen Svalbard Norway Department of Geosciences University of Oslo Oslo Norway Deceased Paleogeophysics & Geodynamics Stockholm Sweden

This is the second paper in a series of two, which analyze the position of the Barents Sea ice-edge (BIE) based on a 442-year long dataset to understand its time variations. The data have been collected from ship-logs, polar expeditions, and hunters in addition to airplanes and satellites in recent times. Our main result is that the BIE position alternates between a southern and a northern position followed by Gulf Stream Beats (GSBs) at the occurrence of deep solar minima. We decompose the low frequency BIE position variations in cycles composed of dominant periods which are related to the Jose period of 179 years, indicating planetary forcings. We propose that the mechanism transferring planetary signals into changes in BIE position is the solar wind (SW), which provides magnetic shielding of the Earth in addition to geomagnetic disturbances. Increase in the solar wind produces pressure which decelerates the Earth’s rotation. It also transfers electrical energy to the ring current in the earth’s magnetosphere. This current magnetizes the earth’s solid core and makes it rotate faster. To conserve angular momentum the earth’s outer fluid mantle rotates slower with a delay of about 100 years. In addition will geomagnetic storms, initiated by solar coronal mass ejections (CmEs) penetrate deep in the Earth’s atmosphere and change pressure pattern in the Arctic. This effect is larger during solar minima since the magnetic shielding then is reduced. The Arctic may then experience local warming. The transition of solar activities to a possibly deep and long minimum in the present century may indicate Arctic cooling and the BIE moving south this century. For the North Atlantic region, effects of the BIE expanding southward will have noticeable consequences for the ocean bio-production from about 2040.

关键词： Barents Sea Ice Edge Position Cyclic and Non-Linear Changes Lunar and Solar Forcing Planetary Orbit Synchronization

Open Partial Nephrectomy: One Night Length of Stay Is Safe and Cost Effective

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Open Journal of Urology 2016年第9期6卷 139-146页

作者： mohit Sirohi Kyrollis Attalla Harris m. Nagler erik T. Goluboff mount Sinai Beth Israel New York USA

Objective: To review our open partial nephrectomy (OPN) experience and compare to known robotic partial nephrectomy (RPN) data to determine whether length of stay (LOS) and morbidity are significant drivers in the surgical approach employed for partial nephrectomy. methods: We reviewed our OPN experience during the last 3 years examining age, tumor size, LOS, pathology, blood loss, complications, recurences, and deaths. Results: Seventy-five patients underwent OPN during this period. mean age was 59 years, tumor size 2.8 cm, percent malignant 75%, estimated blood loss 350 cc. With a median follow-up of 18 months, there was one urinoma managed by drain-age, one pseudo aneurysm that required embolization and one pulmonary embolism that required anticoagulation. There were no readmissions, no tumor recurences, and no deaths. Our major complication rate was 4% as compared to other trials that re-ported major complication rates between 1% - 9% for RPN and between 3% - 24% for OPN. In the first half of the experience (n = 37), median LOS was 57 hours. Using a pathway encouraging early ambulation and smaller incisions in the second half of the experience (n = 38), median LOS was 35 hours. This is much shorter than reported RPN LOS of 62 - 67 hours and OPN LOS of 108 - 142 hours. Conclusion: OPN can be performed safely and effectively with one night hospital stay. This provides a more cost-effective approach to partial nephrectomy with similar or better complication rates and calls into question the main value drivers of RPN.

关键词： Cost Effective Length of Stay Open Partial Nephrectomy Robotic Partial Nephrectomy

A Generic Workflow for the Data FAIRification Process

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Data Intelligence 2020年第1期2卷 56-65页

作者： Annika Jacobsen Rajaram Kaliyaperumal Luiz Olavo Bonino da Silva Santos Barend mons erik Schultes marco Roos mark Thompson Leiden University medical Center Leiden2333 ZAThe Netherlands GO FAIR International Support&Coordination Office(GFISCO) LeidenThe Netherlands

The FAIR guiding principles aim to enhance the Findability,Accessibility,Interoperability and Reusability of digital resources such as data,for both humans and *** process of making data FAIR(“FAIRification”)can be described in multiple *** this paper,we describe a generic step-by-step FAIRification workflow to be performed in a multidisciplinary team guided by FAIR data *** FAIRification workflow should be applicable to any type of data and has been developed and used for“Bring Your Own Data”(BYOD)workshops,as well as for the FAIRification of e.g.,rare diseases *** steps are:1)identify the FAIRification objective,2)analyze data,3)analyze metadata,4)define semantic model for data(4a)and metadata(4b),5)make data(5a)and metadata(5b)linkable,6)host FAIR data,and 7)assess FAIR *** each step we describe how the data are processed,what expertise is required,which procedures and tools can be used,and which FAIR principles they relate to.

关键词： FAIR data FAIRification workflow FAIR data stewardship Hands-on FAIRification FAIR dissemination

Amylopectin structure and crystallinity explains variation in digestion kinetics of starches across botanic sources in an in vitro pig model

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Journal of Animal Science and Biotechnology 2019年第1期10卷 115-127页

作者： Bianca m.J.martens Walter J.J.Gerrits erik m.A.m.Bruininx Henk A.Schols Laboratory of Food Chemistry Wageningen University and Research Animal Nutrition Group Wageningen University and Research Royal Agrifirm Group Agrifirm North West Europe

Background: Starch is the main source of energy in commonly used pig *** effects related to the extent of starch digestion,also several effects related to variation in digestion rate have recently been demonstrated in *** rates of starch digestion in animals and in in vitro models have been reported,depending on the botanic origin of *** from different botanic sources differ widely in structural and molecular *** the effect of starch properties on in vitro digestion kinetics based on existing literature is hampered by incomplete characterization of the starches,or by a selective choice of starches from a limited number of botanic *** research aimed to analyse the relationships between starch properties and in vitro digestion kinetics of pure starches isolated from a broad range of botanic origins,which are used in non-ruminant diets or have a potential to be used in the *** we studied starch digestion kinetics of potato,pea,corn,rice,barley,and wheat starches,and analysed the granule diameter,number of pores,type and amount of crystalline structure,amylose content and amylopectin side-chain length of all ***: multivariate analysis revealed strong correlations among starch properties,leading us to conclude that effects of most starch characteristics are strongly *** all analysed botanic sources,crystalline type and amylopectin chain length showed the strongest correlation with in vitro digestion *** percentages of A–type crystalline structure and amylopectin side chains of DP 6–24 both increased the rate of *** addition,within,but not across,(clusters of) botanic sources,a decrease in amylose content and increase in number of pores correlated positively with digestion ***: The type of crystalline structure and amylopectin chain length distribution of starch correlate significantly with digestion kinetics of starches ac

关键词： Amylopectin side chain distribution Amylose Granule diameter In vitro digestion kinetics Pores

An analysis of quantitative PCR reliability through replicates using the C_(t)method

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Journal of Biomedical Science and Engineering 2010年第5期3卷 459-469页

作者： Chris C.Stowers Frederick R.Haselton erik m.Boczko Bioprocess R&D Division Dow AgroSciences LLC Indianapolis IndianaUSA Department of Biomedical Engineering Vanderbilt University Nashville NashvilleUSA Department of Biomedical Informatics Vanderbilt University medical Center Nashville NashvilleUSA

There is considerable interest in quantitatively measuring nucleic acids from single cells to small populations. The most commonly employed laboratory method is the real-time polymerase chain reaction (PCR) analyzed with the crossing point or crossing threshold (Ct) method. Utilizing a multiwell plate reader we have performed hundreds of replicate reactions each at a set of initial conditions whose initial number of copies span a concentration range of ten orders of magnitude. The resultant Ct value distributions are analyzed with standard and novel statistical techniques to assess the variability/reliability of the PCR process. Our analysis supports the following conclusions. Given sufficient replicates, the mean and/or median Ct values are statistically distinguishable and can be rank ordered across ten orders of magnitude in initial template concentration. As expected, the variances in the Ct distributions grow as the number of initial copies declines to 1. We demonstrate that these variances are large enough to confound quantitative classi?cation of the initial condition at low template concentrations. The data indicate that a misclassi?cation transition is centered around 3000 initial copies of template DNA and that the transition region correlates with independent data on the thermal wear of the TAQ polymerase enzyme. We provide data that indicate that an alternative endpoint detection strategy based on the theory of well mixing and plate ?lling statistics is accurate below the mis- classi?cation transition where the real time method becomes unreliable.

关键词： misclassification Transition Single molecule Counting Rank Ordering Running Title PCR Replicates and Reliability

A Coaching Program for Recently Licensed Young Drivers in the Netherlands： Which Drivers Are Attracted？

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Journal of Traffic and Transportation Engineering 2014年第2期2卷 85-96页

作者： erik C. Roelofs Jan A.m.m. Vissers marieke J.H. van Onna measurement and Research Department Cito Arnhem 1034 the Netherlands Unit Transport Royal HaskoningDHV Amersfoort 1132 the Netherlands

In line with European developments, a Dutch second phase coaching program, referred to as the DX- （Driver Xperience） program, was developed for young novice drivers to counteract their high accident risk. more specifically, the aim of the DX-program was to enable young drivers to make responsible decisions and develop positive attitudes regarding four levels of the driving task： combining life style and driving, planning and navigation, participating in different traffic situations and handling the vehicle. In this paper, the design principles of the program are described. The empirical study focused on the entry characteristics of the participating young drivers （n = 3,117） as compared to a reference group of young drivers （n = 345）. Results show that the DX-program attracted young drivers that, in some respects, showed a more risky profile than average young drivers in terms of speed violations, anger and the number of fines. In addition, four groups of participants with sharply differing driving styles could be distinguished. Implications for educational design and follow-up research are discussed within the theoretical framework of self-regulated learning.

关键词： Coaching young drivers group heterogeneity driving style self-regulated learning learning motivation.

Development and Evaluation of a Competence-BasedExam for Prospective Driving Instructors

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Journal of Traffic and Transportation Engineering 2015年第3期3卷 147-157页

作者： erik C. Roelofs maria Bolsinova Angela Verschoor Jan A. m. m. Vissers measurement and Research Department Cito Arnhem 1034 the Netherlands Unit Transport Royal HaskoningDHV Amersfoort 1132 the Netherlands

According to changed views on driver training and driverintroduced in the Netherlands. The exam consists of two parts：（l）instructor preparation, a competence-based instructor exam wasmultimedia theory tests; （2） a performance lesson for drivinginstruction and coaching. An implicit idea behind the innovated exam is that it can have a positive backwash effect on the quality ofdriver instructor preparation programs. This study aims to evaluate the reliability, validity and fairness of the theoretical tests, whichappear in different versions for successive groups of PDIs （prospective driving instructors）. Data of 4,741 PDIs, enrolled during theperiod between January 2010 and October 2012, were used for analysis. The results of psychometric analyses show that the theory testsyielded reliable and fair decisions about instructor certification. The predictive validity of the theory tests for the final performanceassessment was low. Implications for the design and on-the-fly maintenance of exam item banks are discussed. Follow-up studies willfocus on the question, whether the improved instructor exam produces safer drivers in the end.

关键词： Prospective driving instructors, evidence centered design, validity, competence-based exams.

Evolution in microstructure and mechanical properties during back-annealing of AlmnFeSi alloy

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Transactions of Nonferrous metals Society of China 2012年第8期22卷 1878-1883页

作者：王宁 Jarl erik FLATφY 李彦军 Knut mARTHINSEN Department of materials Science and Engineering Norwegian University of Science and TechnologyNO-7491TrondheimNorway SINTEF materials and Chemistry NO-7465TrondheimNorway

An Al-mn-Fe-Si model alloy was subjected to two homogenization treatments, to achieve materials with different levels of mn in solid solution and dispersoid densities, followed by cold rolling and back-annealing. Characterization of homogenization and deformation structures with respect to the effect of different microchemistries and strains on the structures was performed. Time-temperature-transformation （TTT） diagram with respect to precipitation and recrystallisation as a basis for analysis of the degree of concurrent precipitation was established. The TTT-diagram shows a strong effect of mn concentration in solid solution and dispersoid density on the softening behavior. Recrystallization which finishes without the effect of concurrent precipitation results in an even, fine and equiaxed grain structure. Precipitation prior to or during recrystallization （concurrent） does retard the softening kinetics and leads to a coarse grain structure. However, the effect also depends on the duration of recrystallization and amount of precipitation. Recrystallization proceeding over a long time combined with a large amount of concurrent precipitation has a strong effect, otherwise the effect will be limited. Pre-existing fine and dense dispersoids （mean size 0.1 μm） before back-annealing do also lead to a coarse grain structure after recrystallization no matter whether additional concurrent precipitation occurs.

关键词： homogenization treatment dispersoid phase solid solution back-annealing recrystallization concurrent precipitation TTT-diagram