9,222 research outputs found
When resources collide: Towards a theory of coincidence in information spaces
This paper is an attempt to lay out foundations for a general theory of coincidence in information spaces such as the World Wide Web, expanding on existing work on bursty structures in document streams and information cascades. We elaborate on the hypothesis that every resource that is published in an information space, enters a temporary interaction with another resource once a unique explicit or implicit reference between the two is found. This thought is motivated by Erwin Shroedingers notion of entanglement between quantum systems. We present a generic information cascade model that exploits only the temporal order of information sharing activities, combined with inherent properties of the shared information resources. The approach was applied to data from the world's largest online citizen science platform Zooniverse and we report about findings of this case study
Deformation monitoring of high-latitude permafrost region of northeastern China with time series inSAR technique
Abstract. Permafrost distributed in northeast China is the only high-altitude permafrost in China. The deformation monitoring over this permafrost region is of great importance to local climate change and ecological environments. This study focuses on the deformation monitoring of high-latitude permafrost in northeast China with time series InSAR technique. The spatial distribution characteristics, the annual deformation rates and the temporal deformation evolutions of permafrost could be retrieved from multi-temporal InSAR processing with Sentinel-1 TOPS datasets. This work concludes that time series InSAR technique could help to retrieve a comprehensive and reliable permafrost deformation, while a long time-series of displacements facilitated to better understand permafrost kinematics.</p
Extreme Sensitivity of Superconductivity to Stoichiometry in FeSe (Fe1+dSe)
The recently discovered iron arsenide superconductors, which display
superconducting transition temperatures as high as 55 K, appear to share a
number of general features with high-Tc cuprates, including proximity to a
magnetically ordered state and robustness of the superconductivity in the
presence of disorder. Here we show that superconductivity in Fe1+dSe, the
parent compound of the superconducting arsenide family, is destroyed by very
small changes in stoichiometry. Further, we show that non-superconducting
Fe1+dSe is not magnetically ordered down to low temperatures. These results
suggest that robust superconductivity and immediate instability against an
ordered magnetic state should not be considered as intrinsic characteristics of
iron-based superconducting systems, and that Fe1+dSe may present a unique
opportunity for determining which materials characteristics are critical to the
existence of superconductivity in high Tc iron arsenide superconductors and
which are not.Comment: Updated to reflect final version and include journal referenc
Anomalous thermoelectric effects of ZrTe in and beyond the quantum limit
Thermoelectric effects are more sensitive and promising probes to topological
properties of emergent materials, but much less addressed compared to other
physical properties. Zirconium pentatelluride (ZrTe) has inspired active
investigations recently because of its multiple topological nature. We study
the thermoelectric effects of ZrTe in a magnetic field and find several
anomalous behaviors. The Nernst response has a steplike profile near zero field
when the charge carriers are electrons only, suggesting the anomalous Nernst
effect arising from a nontrivial profile of Berry curvature. Both the
thermopower and Nernst signal exhibit exotic peaks in the strong-field quantum
limit. At higher magnetic fields, the Nernst signal has a sign reversal at a
critical field where the thermopower approaches to zero. We propose that these
anomalous behaviors can be attributed to the Landau index inversion, which is
resulted from the competition of the dependence of the Dirac-type
Landau bands and linear- dependence of the Zeeman energy ( is the
magnetic field). Our understanding to the anomalous thermoelectric properties
in ZrTe opens a new avenue for exploring Dirac physics in topological
materials.Comment: 6 pages, 4 figure
Feasibility Study of a Facility to Produce Injection Molded Parts for Automotive Industry
[EN] This study aims at the preliminary assessment in designing a complete stand-alone industrial facility to produce injection molded parts for the automotive industry. A draft design solution to allow the company to evaluate the capital investment was performed giving an estimated solution in project profitability. Proposed successive design steps were developed. It includes the definition of input data and information, quantity determination, plat layout diagrams, machine selection, selection of material handling equipment, plant layout design including space requirements of production centers, aĂsles, support functions. Moreover, the outdoor facility masterplan design is also proposed. Finally, investment calculation via cash flow analysis is calculated.Yudianto, A.; Tan, H.; Qu, Z.; Xue, Q.; Naveen, A.; Mushtaq, M.; Gopi, K. (2020). Feasibility Study of a Facility to Produce Injection Molded Parts for Automotive Industry. International Journal of Production Management and Engineering. 8(1):45-57. https://doi.org/10.4995/ijpme.2020.12360455781Al-Aomar, R. (2006). Capacity-constrained production scheduling of multiple vehicle programs in automotive pilot plant. International Journal of Production Research, 44(13), 2573-2604. https://doi.org/10.1080/00207540500521212Cagliano, A. C., Chiabert, P. (2018). Plant and manufacturing system lecture notes. Politecnico di Torino, Italy.Chingua, S. Nyemba, W. R., Boora, K., Mbohwa, C. (2019). Feasibility study of the materials handling and development of a sustainable conveying system in plastics recycling and manufacture. Procedia Manufacturing, 33, 383-390. https://doi.org/10.1016/j.promfg.2019.04.047Derhami, S., Smith, J. S., Gue, K. R. (2019). Space-efficient layouts for block stacking warehouse. IISE Transaction, 51(9), 957-971. https://doi.org/10.1080/24725854.2018.1539280Eksangsri, T., Jaiwang, T. (2014). Feasibility study on reuse of washed water in electronic industry: case study for flexible printed circuit board manufacturing in Thailand. Procedia Environmental Sciences, 20, 206-214. https://doi.org/10.1016/j.proenv.2014.03.027Fu, M., Kaku, B. K. (1997). Minimizing work-in-process and material handling in the facilities layout problem. IIE Transactions, 29, 29-36. https://doi.org/10.1080/07408179708966309Halil, F. M., Nasir, N. M., Hassan, A. A., Shukur, A. S. (2016). Feasibility study and economic assessment in green building projects. Procedia-Social and Behavioral Sciences, 222, 56-64. https://doi.org/10.1016/j.sbspro.2016.05.176Hazaras, M. J., Swartz, C. L. E., Marlin, T. E. (2013). Industrial application of a continuous-time scheduling framework for process analysis and improvement. I&EC research Industrial & Engineering Chemistry Research, 53, 259-273. https://doi.org/10.1021/ie4006904Hwang, D. K., Cho, K., Moon, J. (2019). Feasibility study on energy audit and data driven analysis procedure for building energy efficiency: bench-marking in Korean hospital buildings. Journal Energy 12(15), 3006. https://doi.org/10.3390/en12153006Jung, S., Ng, D., Ovalle, C. D., Roman, R, V., Mannan, M. S. (2011). New approach to optimizing the facility sitting and layout for fire and explosion scenarios. I&EC research Industrial & Engineering Chemistry Research, 50, 3928-3937. https://doi.org/10.1021/ie101367gKingenberg, W., Boksma, J. D. (2010). A conceptual framework for outsourcing of material handling activities in automotive: differentiation and implementation. International Journal of Production Research, 48(16), 4877-4899. https://doi.org/10.1080/00207540903067177KovĂ cs, G. (2019). Layout design for efficiency improvement and cost reduction. Bull. Pol. Ac.: Tech., 67(3), 547-555. https://doi.org/10.24425%2Fbpasts.2019.129653Ma, T., Yang, H., Lu. L., Qi, R. (2017). Feasibility study of developing a zero-carbon-emission green deck in Hong Kong. Energy Procedia 105, 1155-1159. https://doi.org/10.1016/j.egypro.2017.03.487Morgan, B., Hejdenberg, J., Krapels, S. H., Amstrong, D. (2018). DO feasibility studies contribute to, or avoid, waste in research? PLos ONE 13(4), e0195951. https://doi.org/10.1371/journal.pone.0195951Pòvoa, A. P. B., (2002). Optimal design and layout of industrial facilities: a simultaneous approach. Ind. Eng. Chem. Res, 41, 3601-3609. https://doi.org/10.1021/ie010660sSchaller, J. (2008). Incorporating cellular manufacturing into supply chain design. International Journal of Production Research, 46(17), 4925-4945. https://doi.org/10.1080/00207540701348761Stephens, M. P., Meyers, F. E., (2013). Manufacturing facilities design and material handling - fifth edition. Purdue University Press, West Lafayette, Indiana.Sun, L., Luan, F., Pian, J. (2015). An effective approach for scheduling of refining process with uncertain iterations in steel-making and continuous casting process. IFAC-PapersOnLine, 48(3), 1966-1972. https://doi.org/10.1016/j.ifacol.2015.06.376Yang, Z., Djurdjanovic, D., Ni, J. (2007). Maintenance scheduling for a manufacturing system of machines with adjustable throughput. IIE Transactions, 39, 1111-1125. https://doi.org/10.1080/0740817070131533
Molecular mechanisms underlying altered neurobehavioural development of female offspring of mothers with polycystic ovary syndrome: FOS-mediated regulation of neurotrophins in placenta
Background:
This study explored the mechanisms underlying altered neurobehavioural development of female offspring born to mothers with polycystic ovary syndrome (PCOS).
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Methods:
In total, 20 women with PCOS and 32 healthy women who underwent caesarean deliveries with a single female foetus were recruited. Infants were assessed with Dubowitz scoring. Swan71 cell line with stable FOS overexpression was used to verify the regulatory effects of FOS on brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) expression. Learning and memory in female first-generation (F1) and second-generation (F2) offspring in a rat model of PCOS was tested using the Morris water maze at puberty and adulthood. Transcriptome analysis of pubertal hippocampi and hypothalami of female F1 offspring was conducted.
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Findings:
Total score and behaviour subscales of Dubowitz scoring were significantly lower in female infants of women with PCOS. FOS and NGF protein levels were downregulated in placental villi of the PCOS group. FOS played a key role in BDNF inhibition and enhancing NGF in Swan71 cells. PCOS female F1 rats exhibited lower target crossing times during puberty when compared to controls. Transcriptome analysis revealed significant changes in hippocampal and hypothalamic neuronal pathways in female F1 rats at puberty.
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Interpretation:
FOS regulation of neurotrophins in the placenta negatively affects neurobehavioural development of female offspring of PCOS mothers
Functional motor recovery from motoneuron axotomy is compromised in mice with defective corticospinal projections
published_or_final_versio
Exploring the Effect of Crowd Management Measures on Passengers’ Behaviour at Metro Stations
To reduce problems of interaction at the platform train interface (PTI) platform edge doors (PEDs) and markings on the platform are used as door positions indicators. The common methods to study the effect of these measures are based on average values of density using Fruin’s Level of Service (LOS), however identification cannot be made of which part of the PTI is more congested. To solve this problem, a new method is proposed. The method included a conceptual model in which the PTI was discretised into 40 cm square cells to identify which part of the platform is more congested. Passengers’ behaviour was recorded considering two situations before the train arrives: i) passengers waiting in front of the doors; ii) passengers waiting beside the doors. Observation was done at existing stations at Metro de Santiago and London Underground. Results show that PEDs changed the behaviour of passengers as they were located beside the doors rather than in front of them. In addition, when markings were used on the platform, then this behaviour was reinforced. Therefore, it is recommended to use this method to better design the PTI rather than the LOS which is used to design the whole platform. Further research is needed to study the effect of PEDs on passengers with reduced mobility
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