365 research outputs found
Straightforward one-pot stereoselective synthesis of substituted tetrahydrofurans from 1,3-butadienes and aldehydes.
International audienceA new and efficient multicomponent reaction involving a double-allylation sequence is reported. In situ generated bimetallic reagents are prepared from disilane and added onto a range of aliphatic aldehydes to afford a direct access to trisubstituted tetrahydrofurans in good to excellent diastereoselectivity (up to 70%)
Détachement d'une microgoutte légèrement déformable sous l'action d'une force électrique
Une goutte conductrice posée sur la plaque inférieure d'un condensateur aux bornes duquel une tension est appliquée acquiert à son interface des charges électriques et subit ainsi l'action d'une force électrostatique normale aux électrodes. Si le champ électrique dépasse une valeur seuil, la force électrique exercée sur la goutte peut provoquer son détachement. Le Ny (1981) a donné les expressions nécessaires au calcul de la charge acquise et l'intensité de la force électrique mais celles-ci sont restreintes aux cas de gouttes indéformables ; il manque un modèle théorique qui tienne compte de la déformation de la goutte (Khayari et col., 2003). Dans la présente communication, nous présentons le calcul asymptotique de la déformation de l'interface sous l'action de la pression électrostatique, pour de petits nombres d'Eötvos et de Bond électrique. Un mécanisme est également proposé pour décrire le détachement d'une goutte posée. Les expériences menées illustrent le mécanisme proposé et confirment les modèles établis
Development of a reliable extraction method for the recovery of total genomic DNA from woodchip colonizing biofilm involved in gas biofiltration
[Abstract] This preliminary study focused on a critical step for the characterization of microbial ecosystem involved in biofiltration. Two aspects of nucleic acid recovery were explored: (i) cell dispersion (three methods tested) and (ii) total DNA extraction (four methods tested). The objective is to select the optimal combination of desorption/extraction methods, allowing subsequent molecular investigations to be reliable. Three relevant criteria are used to assess extraction efficiency: DNA amount and purity, and subsequent amplification feasibility
Development of a Connected Sensor System in Colorectal Surgery:User-Centered Design Case Study
BACKGROUND: A successful innovative medical device is not only technically challenging to develop but must also be readily usable to be integrated into health care professionals’ daily practice. Through a user-centered design (UCD) approach, usability can be improved. However, this type of approach is not widely implemented from the early stages of medical device development. OBJECTIVE: The case study presented here shows how UCD may be applied at the very early stage of the design of a disruptive medical device used in a complex hospital environment, while no functional device is available yet. The device under study is a connected sensor system to detect colorectal anastomotic leakage, the most detrimental complication following colorectal surgery, which has a high medical cost. We also aimed to provide usability guidelines for the initial design of other innovative medical devices. METHODS: UCD was implemented by actively involving health care professionals and all the industrial partners of the project. The methodology was conducted in 2 European hospitals: Grenoble-Alpes University Hospital (France) and Erasmus Medical Center Rotterdam (the Netherlands). A total of 6 elective colorectal procedures and 5 ward shifts were observed. In total, 4 workshops were conducted with project partners and clinicians. A formative evaluation was performed based on 5 usability tests using nonfunctional prototype systems. The case study was completed within 12 months. RESULTS: Functional specifications were defined for the various components of the medical device: device weight, size, design, device attachment, and display module. These specifications consider the future integration of the medical device into current clinical practice (for use in an operating room and patient follow-up inside the hospital) and interactions between surgeons, nurses, nurse assistants, and patients. By avoiding irrelevant technical development, this approach helps to promote cost-effective design. CONCLUSIONS: This paper presents the successful deployment over 12 months of a UCD methodology for the design of an innovative medical device during its early development phase. To help in reusing this methodology to design other innovative medical devices, we suggested best practices based on this case
TER: A Robot for Remote Ultrasonic Examination: Experimental Evaluations
This chapter:
o Motivates the clinical use of robotic tele-echography
o Introduces the TER system
o Describes technical and clinical evaluations performed with TE
Rethinking business models for innovation
One of the major challenges confronted by those in charge of technological innovation involves anticipating the value creation model sufficiently early on,in a highly uncertain context both as far as the technology itself is concerned and the potential market. Today, in many industrial sectors, the innovation boundaries have moved towards projects that are more and more exploratory and fuzzy. The simple optimisation of linear processes of the "stage-gate" type is no longer sufficient to build sustainable competitive advantages. The notion of Business Models, when applied to innovation, enables us to describe how a company creates value through innovation, generally within a business ecosystem, and how the value will be distributed between the actors involved. The authors of this book believe that the notions of Business Modelling and value creation are key to all the dimensions of successful innovation, whether technology, marketing, organisational or economically based. Rethinking Business Models for Innovation: this title describes the relationship between thinking, modelling, and also field-testing. The book is based on a series of nine recent cases of innovation involving company managers, often assisted by researchers (the co-authors of each chapter), and how they built and formalised their Business Models and then tested their strategies. After having discovered the variety of the cases, the reader will understand that every innovation situation generates specific questions about Business Models. However, we feel that we can identify three key issues that arise, more or less, in each of these projects. The chapters in this book build on these issues: the identification of sources of value and revenue models (the notion of value creation), the position of the company in the value-network or ecosystem (the sharing of value) and finally the evolution of Business MoDdels over time (the sustainability and the competitiveness of the company). The last chapter goes over all the contributions, exploring the notion of value in the Business Model approach.business model ; innovation ; value ; entrepreneurial project
Drug development in oncology assisted by noninvasive optical imaging.
International audienceEarly and accurate detection of tumors, like the development of targeted treatments, is a major field of research in oncology. The generation of specific vectors, capable of transporting a drug or a contrast agent to the primary tumor site as well as to the remote (micro-) metastasis would be an asset for early diagnosis and cancer therapy. Our goal was to develop new treatments based on the use of tumor-targeted delivery of large biomolecules (DNA, siRNA, peptides, or nanoparticles), able to induce apoptosis while dodging the specific mechanisms developed by tumor cells to resist this programmed cell death. Nonetheless, the insufficient effectiveness of the vectorization systems is still a crucial issue. In this context, we generated new targeting vectors for drug and biomolecules delivery and developed several optical imaging systems for the follow-up and evaluation of these vectorization systems in live mice. Based on our recent work, we present a brief overview of how noninvasive optical imaging in small animals can accelerate the development of targeted therapeutics in oncology
Bone sialoprotein plays a functional role in bone formation and osteoclastogenesis.
International audienceBone sialoprotein (BSP) and osteopontin (OPN) are both highly expressed in bone, but their functional specificities are unknown. OPN knockout ((-/-)) mice do not lose bone in a model of hindlimb disuse (tail suspension), showing the importance of OPN in bone remodeling. We report that BSP(-/-) mice are viable and breed normally, but their weight and size are lower than wild-type (WT) mice. Bone is undermineralized in fetuses and young adults, but not in older (>/=12 mo) BSP(-/-) mice. At 4 mo, BSP(-/-) mice display thinner cortical bones than WT, but greater trabecular bone volume with very low bone formation rate, which indicates reduced resorption, as confirmed by lower osteoclast surfaces. Although the frequency of total colonies and committed osteoblast colonies is the same, fewer mineralized colonies expressing decreased levels of osteoblast markers form in BSP(-/-) versus WT bone marrow stromal cultures. BSP(-/-) hematopoietic progenitors form fewer osteoclasts, but their resorptive activity on dentin is normal. Tail-suspended BSP(-/-) mice lose bone in hindlimbs, as expected. In conclusion, BSP deficiency impairs bone growth and mineralization, concomitant with dramatically reduced bone formation. It does not, however, prevent the bone loss resulting from loss of mechanical stimulation, a phenotype that is clearly different from OPN(-/-) mice
: Lessons from entrepreneurial projects
International audienceOne of the major challenges confronted by those in charge of technological innovation involves anticipating the value creation model sufficiently early on,in a highly uncertain context both as far as the technology itself is concerned and the potential market. Today, in many industrial sectors, the innovation boundaries have moved towards projects that are more and more exploratory and fuzzy. The simple optimisation of linear processes of the "stage-gate" type is no longer sufficient to build sustainable competitive advantages. The notion of Business Models, when applied to innovation, enables us to describe how a company creates value through innovation, generally within a business ecosystem, and how the value will be distributed between the actors involved. The authors of this book believe that the notions of Business Modelling and value creation are key to all the dimensions of successful innovation, whether technology, marketing, organisational or economically based. Rethinking Business Models for Innovation: this title describes the relationship between thinking, modelling, and also field-testing. The book is based on a series of nine recent cases of innovation involving company managers, often assisted by researchers (the co-authors of each chapter), and how they built and formalised their Business Models and then tested their strategies. After having discovered the variety of the cases, the reader will understand that every innovation situation generates specific questions about Business Models. However, we feel that we can identify three key issues that arise, more or less, in each of these projects. The chapters in this book build on these issues: the identification of sources of value and revenue models (the notion of value creation), the position of the company in the value-network or ecosystem (the sharing of value) and finally the evolution of Business MoDdels over time (the sustainability and the competitiveness of the company). The last chapter goes over all the contributions, exploring the notion of value in the Business Model approach.L'innovation technologique, qu'elle soit conduite par des start-ups ou par de grandes entreprises, n'est plus une condition suffisante de la création de valeur. Créer de la valeur sur des marchés nouveaux nécessite le plus souvent de repenser l'organisation de l'entreprise, sa façon de faire des affaires, ses partenariats stratégiques, autrement dit, son business model. Cet ouvrage se veut un guide pour les porteurs de projets d'innovation en leur fournissant des outils de compréhension et d'analyse de la dimension stratégique de leur projet. Les études de cas présentées sont le fruit d'une collaboration étroite entre les porteurs de chacun des projets et des chercheurs en management de l'innovation reconnus. Au travers de ces cas, trois grandes problématiques sont abordées : l'identification des sources de valeur chez les clients potentiels, la position que l'entreprise pourra prendre dans son écosystème et enfin l'évolution des business models dans le temps. Sur chacun des cas, le lecteur aura accès à une compréhension fine des problèmes stratégiques posés par l'innovation ainsi que des outils de management mis en œuvre pour aider à réfléchir et à agir. (http://www.rethinkingbusinessmodel.net/
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