1,103 research outputs found
A prescriptive approach to qualify and quantify customer value for value-based requirements engineering
Recently, customer-based product development is becoming a popular paradigm. Customer expectations and needs can be identified and transformed into requirements for product design with the help of various methods and tools. However, in many cases, these models fail to focus on the perceived value that is crucial when customers make the decision of purchasing a product. In this paper, a prescriptive approach to support value-based requirements engineering (RE) is proposed, describing the foundations, procedures and initial applications in the context of RE for commercial aircraft. An integrated set of techniques, such as means-ends analysis, part-whole analysis and multi-attribute utility theory is introduced in order to understand customer values in depth and width. Technically, this enables identifying the implicit value, structuring logically collected statements of customer expectations and performing value modelling and simulation. Additionally, it helps to put in place a system to measure customer satisfaction that is derived from the proposed approach. The approach offers significant potential to develop effective value creation strategies for the development of new product
Antigenicity of Recombinant Maltose Binding Protein-Mycobacterium avium subsp. paratuberculosis Fusion Proteins with and without Factor Xa Cleaving
Mycobacterium avium subsp. paratuberculosis causes Johneâs disease (JD) in ruminants. Proteomic studies have shown that M. avium subsp. paratuberculosis expresses certain proteins when exposed to in vitro physiological stress conditions similar to the conditions experienced within a host during natural infection. Such proteins are hypothesized to be ex- pressed in vivo, are recognized by the host immune system, and may be of potential use in the diagnosis of JD. In this study, 50 recombinant maltose binding protein (MBP)-M. avium subsp. paratuberculosis fusion proteins were evaluated using serum samples from sheep infected with M. avium subsp. paratuberculosis, and 29 (58%) were found to be antigenic. Among 50 fusion proteins, 10 were evaluated in MBP fusion and factor Xa-cleaved forms. A total of 31 proteins (62%) were found to be antigenic in either MBP fusion or factor Xa-cleaved forms. Antigenicity after cleavage and removal of the MBP tag was marginally enhanced
Antigenicity of Recombinant Maltose Binding Protein-Mycobacterium avium subsp. paratuberculosis Fusion Proteins with and without Factor Xa Cleaving
Mycobacterium avium subsp. paratuberculosis causes Johneâs disease (JD) in ruminants. Proteomic studies have shown that M. avium subsp. paratuberculosis expresses certain proteins when exposed to in vitro physiological stress conditions similar to the conditions experienced within a host during natural infection. Such proteins are hypothesized to be ex- pressed in vivo, are recognized by the host immune system, and may be of potential use in the diagnosis of JD. In this study, 50 recombinant maltose binding protein (MBP)-M. avium subsp. paratuberculosis fusion proteins were evaluated using serum samples from sheep infected with M. avium subsp. paratuberculosis, and 29 (58%) were found to be antigenic. Among 50 fusion proteins, 10 were evaluated in MBP fusion and factor Xa-cleaved forms. A total of 31 proteins (62%) were found to be antigenic in either MBP fusion or factor Xa-cleaved forms. Antigenicity after cleavage and removal of the MBP tag was marginally enhanced
Antigenicity of Recombinant Maltose Binding Protein-Mycobacterium avium subsp. paratuberculosis Fusion Proteins with and without Factor Xa Cleaving
Mycobacterium avium subsp. paratuberculosis causes Johneâs disease (JD) in ruminants. Proteomic studies have shown that M. avium subsp. paratuberculosis expresses certain proteins when exposed to in vitro physiological stress conditions similar to the conditions experienced within a host during natural infection. Such proteins are hypothesized to be ex- pressed in vivo, are recognized by the host immune system, and may be of potential use in the diagnosis of JD. In this study, 50 recombinant maltose binding protein (MBP)-M. avium subsp. paratuberculosis fusion proteins were evaluated using serum samples from sheep infected with M. avium subsp. paratuberculosis, and 29 (58%) were found to be antigenic. Among 50 fusion proteins, 10 were evaluated in MBP fusion and factor Xa-cleaved forms. A total of 31 proteins (62%) were found to be antigenic in either MBP fusion or factor Xa-cleaved forms. Antigenicity after cleavage and removal of the MBP tag was marginally enhanced
Reducing the debt : is it optimal to outsource an investment?
International audienceWe deal with the problem of outsourcing the debt for a big investment, according two situations: either the firm outsources both the investment (and the associated debt) and the exploitation to a private consortium, or the firm supports the debt and the investment but outsources the exploitation. We prove the existence of Stackelberg and Nash equilibria between the firm and the private consortium, in both situations. We compare the benefits of these contracts. We conclude with a study of what happens in case of incomplete information, in the sense that the risk aversion coefficient of each partner may be unknown by the other partner
Comparison of OMI ozone and UV irradiance data with ground-based measurements at two French sites
International audienceOzone Monitoring Instrument (OMI), launched in July 2004, is dedicated to the monitoring of the Earth's ozone, air quality and climate. OMI provides among other things the total column of ozone (TOC), the surface ultraviolet (UV) irradiance at several wavelengths, the erythemal dose rate and the erythemal daily dose. The main objective of this work is to validate OMI data with ground-based instruments in order to use OMI products (collection 2) for scientific studies. The Laboratoire d'Optique Atmosphérique (LOA) located in Villeneuve d'Ascq in the north of France performs solar UV measurements using a spectroradiometer and a broadband radiometer. The site of Briançon in the French Southern Alps is also equipped with a spectroradiometer operated by Interaction Rayonnement Solaire AtmosphÚre (IRSA). The instrument belongs to the Centre Européen Médical et Bioclimatologique de Recherche et d'Enseignement Supérieur. The comparison between the TOC retrieved with ground-based measurements and OMI TOC shows good agreement at both sites for all sky conditions. Comparisons of spectral UV on clear sky conditions are also satisfying whereas results of comparisons of the erythemal daily doses and erythemal dose rates for all sky conditions and for clear sky show that OMI overestimates significantly surface UV doses at both sites
Cirrus cloud occurrence as function of ambient relative humidity: A comparison of observations from the Southern and Northern Hemisphere midlatitudes obtained during the INCA experiment
International audienceThe occurrence frequency of cirrus clouds as function of ambient relative humidity over ice, based on in-situ observations performed during the INCA experiment, show a clear difference between the campaign carried out at Southern Hemisphere (SH) midlatitudes and the campaign carried out at Northern Hemisphere (NH) midlatitudes. At a given relative humidity above ice saturation, clouds are more frequent in the NH. At relative humidities near ice saturation, clouds defined as containing particles with sizes larger than 0.55 ”m diameter and an integral number density above 0.2 cm-3 were present 70% of the time during the SH campaign, whereas clouds where present 95% of the time during the NH campaign. Using a size threshold of 1 ”m diameter to define the presence of clouds result in a less frequent occurrence of 60% of the time in the SH campaign and 75% of the time in the NH campaign. The data show that the presence of particles is a common characteristic of cirrus clouds. Clouds at ice saturation defined as having crystal sizes of at least 5 ”m diameter and a number density exceeding 0.001 cm-3 were present in about 80% of the time during the SH campaign, and almost 90% of the time during the NH campaign. The observations reveal a significant cloud presence fraction at humidities well below ice saturation. Local minima in the cloud presence fraction as a function of relative humidity are interpreted as systematic underestimation of cloud presence because cloud particles may become invisible to cloud probes. Based on this interpretation the data suggests that clouds in the SH form preferentially at relative humidities between 140 and 155%, whereas clouds in the NH formed at relative humidities less than 130%. A simple assumption about the probability to reach successively higher humidities in an ice supersaturated air parcel provides a model that explains the main trend of the cloud presence fraction as function of relative humidity. If adiabatic processes are assumed a cloud water content distribution can be derived from this probability model. The resulting distribution agrees well in shape compared to observations, but the observed mean cloud water content is less than expected from simply adiabatic processes
Biodiversity conservation, ecosystem services and organic viticulture: A glass half-full
Organic farming is a promising but still debated option to ensure sustainable agriculture. However, whether organic farming fosters synergies or mitigates tradeoffs between biodiversity, ecosystem services and crop production has rarely been quantified. Here, we investigate relationships between multitrophic diversity (14 taxa above and belowground), yield, natural pest control and soil quality (14 proxies of ecosystem services) in organic and conventional vineyards along a landscape gradient. Organic farming enhanced biodiversity and pest control, but decreased wine production. Compared to conventional systems, multitrophic diversity was 15 % higher, and pest control services were 9 % higher in organic systems, while wine production was 11 % lower. Regardless of management type, we found a strong tradeoff between wine production and pest control, but not between wine production and biodiversity. The landscape context was not a strong moderator of organic farming effects across taxa groups and ecosystem services, but affected specific taxa and ecosystem services, especially natural pest control. Our study reveals that wine production and biodiversity conservation do not necessarily exclude each other, which implies the existence of a safe operating space where biodiversity and wine production can be combined. We conclude that organic farming can contribute to improve the sustainability of viticulture, but needs to be complemented by management options at the local and landscape scales in order to fully balance biodiversity conservation with the simultaneous provision of multiple ecosystem services.This research was funded by the research project SECBIVIT, which was funded through the 2017â2018 Belmont Forum and BiodivERsA joint call for research proposals, under the BiodivScen ERA-Net COFUND program, with the funding organizations: Agencia Estatal de InvestigaciĂłn (Ministerio de Ciencia e InnovaciĂłn/Spain, grant PCI2018-092938; MCIN/AEI/10.13039/501100011033); Austrian Science Fund (FWF) (grant number I 4025-B32); Federal Ministry of Education and Research (BMBF/Germany) (grant number 031A349I); French National Research Agency (ANR); Netherlands Organization for Scientific Research (NWO); National Science Foundation (grant #1850943); and Romanian Executive Agency for Higher Education, Research, Development, and Innovation Funding (UEFISCDI). The authors also acknowledge the support of the ECOPHYTO 2+ Plan under the grant X4IN33VI (OPERA project) as well as the support the French National Research Agency (ANR) under the grant 20-PCPA-0010 (PPR Vitae, Cultivating the grapevine without pesticides: towards agroecological wine-producing socio-ecosystems). We thank Evelyne Thys and Hugo Hernandez for their help in field sampling, Lionel Delbac for the Lobesia botrana rearing, Alexis Saintilan for identifying pollinators, and Edith Gruber for identifying earthworms
Stratospheric aerosols from the Sarychev volcano eruption in the 2009 Arctic summer
Aerosols from the Sarychev volcano eruption (Kuril Islands, northeast of Japan) were observed in the Arctic lower stratosphere a few days after the strongest SO2 injection which occurred on 15 and 16 June 2009. From the observations provided by the Infrared Atmospheric Sounding Interferometer (IASI) an estimated 0.9 Tg of sulphur dioxide was injected into the upper troposphere and lower stratosphere (UTLS). The resultant stratospheric sulphate aerosols were detected from satellites by the Optical Spectrograph and Infrared Imaging System (OSIRIS) limb sounder and by the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) and from the surface by the Network for the Detection of Atmospheric Composition Changes (NDACC) lidar deployed at OHP (Observatoire de Haute-Provence, France). By the first week of July the aerosol plume had spread out over the entire Arctic region. The Sarychev-induced stratospheric aerosol over the Kiruna region (north of Sweden) was measured by the Stratospheric and Tropospheric Aerosol Counter (STAC) during eight balloon flights planned in August and September 2009. During this balloon campaign the Micro RadiomĂštre Ballon (MicroRADIBAL) and the Spectroscopie d'Absorption Lunaire pour l'Observation des Minoritaires Ozone et NOx (SALOMON) remote-sensing instruments also observed these aerosols. Aerosol concentrations returned to near-background levels by spring 2010. The effective radius, the surface area density (SAD), the aerosol extinction, and the total sulphur mass from STAC in situ measurements are enhanced with mean values in the range 0.15-0.21 ÎŒm, 5.5-14.7 ÎŒm2 cm-3, 5.5-29.5 Ă 10-4 km-1, and 4.9-12.6 Ă 10-10 kg[S] kg-1[air], respectively, between 14 km and 18 km. The observed and modelled e-folding time of sulphate aerosols from the Sarychev eruption is around 70-80 days, a value much shorter than the 12-14 months calculated for aerosols from the 1991 eruption of Mt Pinatubo. The OSIRIS stratospheric aerosol optical depth (AOD) at 750 nm is enhanced by a factor of 6, with a value of 0.02 in late July compared to 0.0035 before the eruption. The HadGEM2 and MIMOSA model outputs indicate that aerosol layers in polar region up to 14-15 km are largely modulated by stratosphere-troposphere exchange processes. The spatial extent of the Sarychev plume is well represented in the HadGEM2 model with lower altitudes of the plume being controlled by upper tropospheric troughs which displace the plume downward and upper altitudes around 18-20 km, in agreement with lidar observations. Good consistency is found between the HadGEM2 sulphur mass density and the value inferred from the STAC observations, with a maximum located about 1 km above the tropopause ranging from 1 to 2 Ă 10 -9 kg[S] kg-1[air], which is one order of magnitude higher than the background level. © Author(s) 2013.The authors thank the CNES balloon
launching team for successful operations and the Swedish Space
Corporation at Esrange. The ETHER database (CNES-INSUCNRS)
and the CNES âsous-direction Ballonâ are partners of the
project. The StraPolEt ÂŽ e project has been funded by the French ÂŽ
âAgence Nationale de la Rechercheâ (ANR-BLAN08-1-31627),
the âCentre National dâEtudes Spatialesâ (CNES), and the âInstitut ÂŽ
Polaire Paul-Emile Victorâ (IPEV). The AEROWAVE (Aerosols,
Water Vapor and Electricity) and the HALOHA (HALOgen in
High Altitudes) projects have been funded by the recently created
French CNES-INSU Balloon Committee (so-called CSTB). We are
grateful to Slimane Bekki and David Cugniet for their constructive
comments about the AER-UPMC 2-D model, to Marc-Antoine
Drouin for his help about the MIMOSA model, and to the LPC2E
technical team for this successful campaign. Jim Haywood and
Andy Jones were supported by the Joint DECC/Defra Met Office
Hadley Centre Climate Programme (GA01101). IASI was developed
and built under the responsibility of the Centre National
dâEtudes Spatiales (CNES, France). It is flown on board the Metop ÂŽ
satellites as part of the EUMETSAT Polar System. The IASI L1
data are received through the EUMETCast near-real-time data
distribution service. L. Clarisse is a postdoctoral researcher with
FRS-FNRS. We acknowledge the CALIOP team for acquiring
and processing data as well as the ICARE team for providing and
maintaining the computational facilities to store them. Odin is a
Swedish-led satellite project funded jointly by Sweden (SNSB),
Canada (CSA), France (CNES), and Finland (Tekes). This study
was supported by the French VOLTAIRE Labex (Laboratoire
dâExcellence ANR-10-LABX-100-01) managed by the University
of Orleans
Sabotage in Contests: A Survey
A contest is a situation in which individuals expend irretrievable resources to win valuable prize(s). âSabotageâ is a deliberate and costly act of damaging a rivalâs' likelihood of winning the contest. Sabotage can be observed in, e.g., sports, war, promotion tournaments, political or marketing campaigns. In this article, we provide a model and various perspectives on such sabotage activities and review the economics literature analyzing the act of sabotage in contests. We discuss the theories and evidence highlighting the means of sabotage, why sabotage occurs, and the effects of sabotage on individual players and on overall welfare, along with possible mechanisms to reduce sabotage. We note that most sabotage activities are aimed at the ablest player, the possibility of sabotage reduces productive effort exerted by the players, and sabotage may lessen the effectiveness of public policies, such as affirmative action, or information revelation in contests. We discuss various policies that a designer may employ to counteract sabotage activities. We conclude by pointing out some areas of future research
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