1,701 research outputs found
The Business Model Handbook for Developing Countries
The Business Model Handbook (BMH) for developing countries is a proposition for a tool that has the goal to help Small and Medium Sized Enterprises (SME) and local entrepreneurs to design business models that use Information and Communication Technologies (ICT) and particularly the Internet in the context of developing economies. It shall help to develop the urgently needed critical mass of knowledge workers, technology users, and motivated entrepreneurs in order to deploy ICT in businesses of developing countries. Never before the Internet it has been as easy to share and transfer knowledge in such an efficient and global way. The objective of this Paper is twofold. First it proposes a theoretical business model framework (BMF) which shall allow SMEs, but also motivated local entrepreneurs in developing countries to understand the most relevant business issues in the Information Society. The BMF gives special attention to the opportunities that arise out of the use of Information Technology (IT) and particularly the use of the Internet for businesses in emerging economies (i.e. e-commerce). The second objective, which is the introduction of the Business Model Handbook for Developing Countries, shall allow an efficient knowledge transfer of the concepts developed and illustrated in the BMF. Therefore, the BMH should be deployed as a Web based tool, which allows Users to navigate through the concepts and the corresponding real world examples (case studies) and easily learn about business opportunities.developing countries, e-business
Maximal multihomogeneity of algebraic hypersurface singularities
From the degree zero part of logarithmic vector fields along an algebraic
hypersurface singularity we indentify the maximal multihomogeneity of a
defining equation in form of a maximal algebraic torus in the embedded
automorphism group. We show that all such maximal tori are conjugate and in
one-to-one correspondence to maxmimal tori in the degree zero jet of the
embedded automorphism group.
The result is motivated by Kyoji Saito's characterization of quasihomogeneity
for isolated hypersurface singularities and extends its formal version and a
result of Hauser and Mueller.Comment: 5 page
Spatial resolution, spectral metrics and biomass are key aspects in estimating plant species richness from spectral diversity in speciesârich grasslands
Increasing evidence suggests that remotely sensed spectral diversity is linked to plant species richness. However, a conflicting spectral diversityâbiodiversity relationship in grasslands has been found in previous studies. In particular, it
remains unclear how well the spectral diversityâbiodiversity relationship holds in naturally assembled species-rich grasslands. To address the linkage between spectral diversity and plant species richness in a species-rich alpine grassland ecosystem, we investigated (i) the trade-off between spectral and spatial resolution in remote sensing data; (ii) the suitability of three different spectral metrics to describe spectral diversity (coefficient of variation, convex hull volume and spectral species richness) and (iii) the importance of confounding effects of live plant biomass, dead plant biomass and plant life forms on the spectral diversityâbiodiversity relationship. We addressed these questions using remote sensing data collected with consumer-grade cameras with four spectral bands and 10 cm spatial resolution on an unmanned aerial vehicle (UAV), airborne imaging spectrometer data (AVIRIS-NG) with 372 bands and 2.5 m spatial resolution, and a fused data product of both datasets. Our findings suggest that a fused dataset can cope with the requirement of both high spatial- and spectral resolution to remotely measure biodiversity. However, in contrast to several previous studies, we found a negative correlation between plant species richness and spectral metrics based on the spectral information content (i.e. spectral complexity). The spectral diversity calculated based on the spectral complexity was sensitive to live and dead plant biomass. Overall, our results suggest that remote sensing of plant species diversity requires a high spatial resolution, the use of classification-based spectral metrics, such as spectral species richness, and awareness of confounding factors (e.g. plant biomass), which may be ecosystem
specific
Slam das Minas do Rio de Janeiro: Erga a sua voz!
O escopo desse artigo visa salientar o discurso poĂ©tico presente no âSlam das Minas do Rio de Janeiroâ como ato de re(existĂȘncia), trazendo Ă luz o surgimento do coletivo e a sua contribuição para construção de uma sociedade mais inclusiva. Abordaremos o corpo e a sua relevĂąncia para os ambientes outrora lidos como sacralizados, uma vez que o slam, atravĂ©s de tĂĄticas, consegue ocupar alguns desses territĂłrios, evidenciando, assim, outras possibilidades de enfrentamento de problemas sociais que afligem a coletividade
Development of a 3D-printed bio-hybrid skin model for photothermal therapy applications
Skin models or phantoms are valuable tools used in biomaterial research to mimic the structure and function of human skin. Optical skin phantoms, in particular, have emerged as promising solutions for studying light interaction with human skin in various biomedical applications, including imaging and laser treatments. How-ever, current optical skin models have limitations in achieving accurate representations of the real skin. These models often fail to consider important factors such as skin color, skin thickness, integration of ap-pendages (e.g., hair follicles, sweat glands, sebaceous glands), and biological response. In this study, we present a novel approach to overcome the limitations of existing artificial skin phantoms by developing a 3D-printed bio-hybrid skin phantom. Our proposed model aims to replicate the optical and thermal proper-ties of human skin and the complex geometry of hair follicles. To achieve this, we combine a skin model mimicking the optical and thermal properties of human skin with the embedding of biological skin cells. The basis of our bio-hybrid skin model is a 3D-printed tissue phantom material that allows for the fabrication of hair follicle like structures. Subsequently, we incorporate biological cells, such as hair follicle cells, into the skin model and engineer induced hair follicle cells to simulate the effects of photothermal therapy on specif-ic cell populations. This enables a comprehensive study of the optical and thermal mechanisms involved in the complex interaction between skin tissue, hair, and the light source. Additionally, we investigate the influ-ence of skin structures, including skin thickness and color, on the outcomes of photothermal therapy. The knowledge gained from our bio-hybrid skin model extends beyond photothermal therapy applications. It can also contribute to the development and testing of other optical treatments, such photodynamic therapy or photobiomodulation. The novel approach provides a platform to study the optical and thermal interactions in biomedical applications. The insights gained from our bio-hybrid skin model have the potential to en-hance future advancements in the field of biomaterials
DCIP tomografi för kartlÀggning av jorddjup och strukturer i berg
There are plans to build an energy storage in the rock at Ănneslöv near Dalby in SkĂ„ne. The bedrock is of a part of RomeleĂ„sen and mainly comprises gneiss, with elements of amphibolite and dolerite intrusions. The area is located immediately south of the Sydstenâs large rock quarry, which shows that the rock is mostly heavily fractured with clay weathered zones of different sizes. In connection with underground construction fractured zones and weathering constitutes a risk for problems with water inflow and stability. Furthermore, variations in depth to the upper surface of the rock can lead to stability problems in the upper portions of a planned construction.Electric resistivity tomography (ERT) is now an established pre-investigation method for tunnel projects, and it has been used on a large scale in connection with for example the HallandsĂ„s Tunnel. The method provides continuous models of variations in the electrical properties of the rock in two (2D) and three dimensions (3D) that can be linked to variations in the rock mechanical and hydraulic properties. ERT measured by a combination of DC resistivity and induced polarization can be called DCIP tomography, which can provide additional information about the variation in the material properties of the rock. With the help of new and improved methods of data acquisition, processing and interpretation it is possible to collect large amounts of good quality IP data in a time and cost effective way, paving the way for better and more nuanced models of the rock and variations in its properties. The newly developed technology has been tested in full scale at Ănneslöv. Three parallel DCIP sections about 1 km long, with a maximum survey depth of about 170 m were measured, plus a 800 m long cross-section. Furthermore, DCIP logging was carried out in two percussion drill holes down to 200 m depth in which it is furthermore made logging of diameter, natural gamma radiation, seismic velocity and flow rate during pumping.Geological interpretation of the DCIP results agree well with what one can expect from the documentation of soil depth, and variation in degree of fracturing and weathering as documented from drilling. A major advantage is continuous models that can be linked to variation in soil depth, structures in the rock and hydrogeological conditions. The combined surveys with surface-based measurements and borehole measurements are complementary and provide a more reliable overall picture of the variations in rock conditions
Disruption of Coronin 1 Signaling in T Cells Promotes Allograft Tolerance while Maintaining Anti-Pathogen Immunity
The ability of the immune system to discriminate self from non-self is essential for eradicating microbial pathogens but is also responsible for allograft rejection. Whether it is possible to selectively suppress alloresponses while maintaining anti-pathogen immunity remains unknown. We found that mice deficient in coronin 1, a regulator of naive T cell homeostasis, fully retained allografts while maintaining T cell-specific responses against microbial pathogens. Mechanistically, coronin 1-deficiency increased cyclic adenosine monophosphate (cAMP) concentrations to suppress allo-specific T cell responses. Costimulation induced on microbe-infected antigen presenting cells was able to overcome cAMP-mediated immunosuppression to maintain anti-pathogen immunity. In vivo pharmacological modulation of this pathway or a prior transfer of coronin 1-deficient T cells actively suppressed allograft rejection. These results define a coronin 1-dependent regulatory axis in T cells important for allograft rejection and suggest that modulation of this pathway may be a promising approach to achieve long-term acceptance of mismatched allografts
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