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The impact of low energy proton damage on the operational characteristics of EPIC-MOS CCDs
The University of Tübingen 3.5 MeV Van de Graaf accelerator facility was used to investigate the effect of low energy protons on the performance of the European Photon Imaging Camera (EPIC), metal–oxide semiconductor (MOS), charge coupled devices (CCDs). Two CCDs were irradiated in different parts of their detecting areas using different proton spectra and dose rates. Iron-55 was the calibration source in all cases and was used to measure any increases in charge transfer inefficiency (CTI) and spectral resolution of the CCDs. Additional changes in the CCD bright pixel table and changes in the low X-ray energy response of the device were examined.
The Monte Carlo code Stopping Range of Ions in Matter (SRIM) was used to model the effect of a 10 MeV equivalent fluence of protons interacting with the CCD. Since the non-ionising energy loss (NIEL) function could not be applied effectively at such low proton energies. From the 10 MeV values, the expected CTI degradation could be calculated and then compared to the measured CTI changes
Erratum to ?Cell directional persistence and chemotaxis in vascular morphogenesis? [Bull. Math. Biol. 66 (2004) 1851?1873]
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The dynamics of grouping-induced biases in apparent numerosity revealed by a continuous tracking technique
Connecting pairs of items causes robust underestimation of the numerosity of an ensemble, presumably by invoking grouping mechanisms. Here we asked whether this underestimation in numerosity judgments could be revealed and further explored by continuous tracking, a newly developed technique that allows for fast and efficient data acquisition and monitors the dynamics of the responses. Participants continuously reproduced the perceived numerosity of a cloud of dots by moving a cursor along a number line, while the number of dots and the proportion connected by lines varied over time following two independent random walks. The technique was robust and efficient, and correlated well with results obtained with a standard psychophysics task. Connecting objects with lines caused an underestimation of approximately 15% during tracking, agreeing with previous studies. The response to the lines was slower than the response to the physical numerosity, with a delay of approximately 150 ms, suggesting that this extra time is necessary for processing the grouping effect
Aplicação de calcário na linha de semeadura para cultura da soja.
As recomendações de calcário adotadas baseiam-se atualmente nas quantidades necessárias para elevar o pH do solo a 6,0, promovendo com isso a neutralização do alumĂnio tĂłxico (e manganĂŞs) para as plantas.bitstream/item/83844/1/CNPT-CIRCULAR-1-APLICACAO-DE-CALCARIO-NA-LINHA-DE-SEMEADURA-PARA-CULTURA-DE-SOJA-FL-13416.pd
Multiphase modelling of tumour growth and extracellular matrix interaction: mathematical tools and applications
Resorting to a multiphase modelling framework, tumours are described here as a mixture of tumour and host cells within a porous structure constituted by a remodelling extracellular matrix (ECM), which is wet by a physiological extracellular fluid. The model presented in this article focuses mainly on the description of mechanical interactions of the growing tumour with the host tissue, their influence on tumour growth, and the attachment/detachment mechanisms between cells and ECM. Starting from some recent experimental evidences, we propose to describe the interaction forces involving the extracellular matrix via some concepts coming from viscoplasticity. We then apply the model to the description of the growth of tumour cords and the formation of fibrosis
Respostas a tecnologias de trigo nos anos de 1981 e 1982.
bitstream/item/119404/1/FOL-06027.pd
Energy based vessel sealing devices in thyroid surgery: A systematic review to clarify the relationship with recurrent laryngeal nerve injuries
Background and objectives: The principal complications associated with thyroid surgery consist in postoperative recurrent laryngeal nerve (RLN) palsy, hypoparathyroidism, intra-operative and post-operative hemorrhage. In this paper, structured as a literature review, we describe the current knowledge and the technical improvements currently employed in the field of thyroid surgery, focusing on the contribution of energy based devices in relation with the reduction of the operating time and the odds of possible complication. Materials and methods: a relevant systematic literature search on Pubmed was carried out including works from 2004 through 2019, selecting studies providing information on the energy based devices employed in surgeries and statistic data concerning RNL (transient and permanent) injury and operative time. Results: Nineteen studies were reviewed, dealing with 4468 patients in total. The operative variables considered in this study are: employed device, number of patients, pathological conditions affecting the patients, surgical treatment, RNL injury percentage and the operating time, offering an insight on different patient conditions and their relative operative outcomes. A total of 1843 patients, accounting to the 41.2% of the total pool, underwent the traditional technique operation, while 2605 patients (58.3%) were treated employing the energy based devices techniques. Thyroidectomy performed by approaches different from traditional (for example robotic, MIVAT (Mini Invasive Video Assisted thyroidectomy)) were excluded from this study. Conclusions: The energy-based vessel sealing devices in study, represent a safe and efficient alternative to the traditional clamp-and-tie hand technique in the thyroidal surgery scenario, granting a reduction in operating time while not increasing RNL injury rates. According to this information, a preference for energy based devices techniques might be expressed, furthermore, a progressively higher usage rate for these devices is expected in the near future
SiPM and front-end electronics development for Cherenkov light detection
The Italian Institute of Nuclear Physics (INFN) is involved in the
development of a demonstrator for a SiPM-based camera for the Cherenkov
Telescope Array (CTA) experiment, with a pixel size of 66 mm. The
camera houses about two thousands electronics channels and is both light and
compact. In this framework, a R&D program for the development of SiPMs suitable
for Cherenkov light detection (so called NUV SiPMs) is ongoing. Different
photosensors have been produced at Fondazione Bruno Kessler (FBK), with
different micro-cell dimensions and fill factors, in different geometrical
arrangements. At the same time, INFN is developing front-end electronics based
on the waveform sampling technique optimized for the new NUV SiPM. Measurements
on 11 mm, 33 mm, and 66 mm NUV SiPMs
coupled to the front-end electronics are presentedComment: In Proceedings of the 34th International Cosmic Ray Conference
(ICRC2015), The Hague, The Netherlands. All CTA contributions at
arXiv:1508.0589
Impacto de espécies de inverno no rendimento de grãos de culturas de verão e de trigo no inverno subseqüente.
bitstream/CNPT-2010/40292/1/p-bp19.pd
Deuda, trabajo y coerciĂłn. Las experiencias de colonizaciĂłn canaria en el Estado Oriental del Uruguay (1830-1843)
This article analyzes the experiences of colonization from the Canary Islands driven by private entrepreneurs and backed by the Uruguayan State during the 1830s. This was a special type of immigration, close to indenture servitude, where individuals moving across the continents signed a contract that forced them to keep working in Uruguay until the debt they had incurred (the cost of their maritime passage) was repaid. The Uruguayan State, through the police, was both the guarantor and enforcer of these contracts.Este artĂculo pretende analizar las experiencias de colonizaciĂłn canaria impulsadas por particulares y con respaldo del Estado uruguayo durante la dĂ©cada de 1830. Se trata de un tipo especial de inmigraciĂłn, ya que los individuos firmaban un contrato que los obligaba a permanecer trabajando en Uruguay hasta saldar la deuda de su pasaje desde Europa. El Estado, a travĂ©s de la policĂa, actuaba como garante del cumplimiento de los contratos
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