Engineering the Virtual Enterprise: An Architecture-Driven Modeling Approach

The managerial and organization practices required by an increasingly dynamic competitive manufacturing, business, and industrial environment include the formation of “virtual enterprises.” A major concern in the management of virtual enterprises is the integration and coordination of business processes contributed by partner enterprises. The traditional methods of process modeling currently used for the design of business processes do not fully support the needs of the virtual enterprise. The design of these virtual enterprises imposes requirements that make it more complex than conventional intraorganizational business process design. This paper first describes an architecture that assists in the design of the virtual enterprise. Then it discusses business process reengineering (BPR) as a methodology for modeling and designing virtual organizations. While BPR presents many useful tools, the approach itself and the modeling tools commonly used for redesign have fundamental shortcomings when dealing with the virtual enterprise. However, several innovative modeling approaches provide promise for this problem. The paper discusses some of these innovative modeling approaches, such as object-oriented modeling of business processes, agent modeling of organizational players, and the use of ontological modeling to capture and manipulate knowledge about the players and processes. The paper concludes with a conceptual modeling methodology that combines these approaches under the enterprise architecture for the design of virtual enterprises.     

Identification of mouse langerin/CD207 in Langerhans cells and some dendritic cells of lymphoid tissues.

Human (h)Langerin/CD207 is a C-type lectin of Langerhans cells (LC) that induces the formation of Birbeck granules (BG). In this study, we have cloned a cDNA-encoding mouse (m)Langerin. The predicted protein is 66% homologous to hLangerin with conservation of its particular features. The organization of human and mouse Langerin genes are similar, consisting of six exons, three of which encode the carbohydrate recognition domain. The mLangerin gene maps to chromosome 6D, syntenic to the human gene on chromosome 2p13. mLangerin protein, detected by a mAb as a 48-kDa species, is abundant in epidermal LC in situ and is down-regulated upon culture. A subset of cells also expresses mLangerin in bone marrow cultures supplemented with TGF-beta. Notably, dendritic cells in thymic medulla are mLangerin-positive. By contrast, only scattered cells express mLangerin in lymph nodes and spleen. mLangerin mRNA is also detected in some nonlymphoid tissues (e.g., lung, liver, and heart). Similarly to hLangerin, a network of BG form upon transfection of mLangerin cDNA into fibroblasts. Interestingly, substitution of a conserved residue (Phe(244) to Leu) within the carbohydrate recognition domain transforms the BG in transfectant cells into structures resembling cored tubules, previously described in mouse LC. Our findings should facilitate further characterization of mouse LC, and provide insight into a plasticity of dendritic cell organelles which may have important functional consequences.     

Front Cover: Photoacoustic imaging of the human placental vasculature (J. Biophotonics 4/2020)

Successful therapy of twin‐to‐twin transfusion syndrome requires accurate imaging to guide laser photocoagulation of the anastomosing placental vessels. Photoacoustic (PA) imaging is an alternative imaging method that provides contrast for hemoglobin, and in this study, it was used to visualize chorionic superficial and subsurface vasculature in human placentas. The strong potential of PA imaging to guide minimally invasive fetal therapies was demonstrated. Further details can be found in the article by Efthymios Maneas, Rosalind Aughwane, Nam Huynh, et al. ( e201900167 ).

     

The effect of experimental warming and precipitation change on proteolytic enzyme activity: positive feedbacks to nitrogen availability are not universal

Nitrogen regulates the Earth's climate system by constraining the terrestrial sink for atmospheric CO₂. Proteolytic enzymes are a principal driver of the within‐system cycle of soil nitrogen, yet there is little to no understanding of their response to climate change. Here, we use a single methodology to investigate potential proteolytic enzyme activity in soils from 16 global change experiments. We show that regardless of geographical location or experimental manipulation (i.e., temperature, precipitation, or both), all sites plotted along a single line relating the response ratio of potential proteolytic activity to soil moisture deficit, the difference between precipitation and evapotranspiration. In particular, warming and reductions in precipitation stimulated potential proteolytic activity in mesic sites – temperate and boreal forests, arctic tundra – whereas these manipulations suppressed potential activity in dry grasslands. This study provides a foundation for a simple representation of the impacts of climate change on a central component of the nitrogen cycle.     

Ultradian cycles in mice: definitions and links with REMS and NREMS

Sleep can be organized in two quite different ways across homeothermic species: either in one block (monophasic), or in several bouts across the 24 h (polyphasic). Yet, the main relationships between variables, as well as regulating mechanisms, are likely to be similar. Correlations and theories on sleep regulation should thus be examined on both types of sleepers. In previous studies on monophasic humans, we have shown preferential links between the number of ultradian cycles and the rapid eye movement sleep (REMS) time, rather than with its counterpart non-rapid eye movement sleep (NREMS). Here, the sleep of 26 polyphasic mice was examined, both to better describe the NREMS distribution, which is far more complex than in humans, and to replicate the analyses performed on humans. As in humans, the strongest links with the number of cycles were with REMS. Links were not significant with NREMS taken as a whole, although positive correlations were found with the NREMS immediately preceding REMS episodes and inversely significant with the residue. This convergence between monophasic and polyphasic patterns supports the central role played by REMS in sleep alternation.     

Electrophysiological maturation of neurons of the lateral geniculate nucleus after lesion of ponto-geniculo-occipital pathways in kittens

Bilateral mesencephalic lesions, which suppress the PGO activity in the lateral geniculate nucleus (LGN), were performed at two weeks of age in the kitten, and the effects on the electrophysiological development of this nucleus were analyzed at 6 weeks of age. The latencies of LGN cells after electrical stimulation of the optic chiasma were larger, and the number of the differentiated X cells was smaller than those of age paired controls. However, the response of the ganglion fibers was not modified. These results, compared to those obtained on 30 days old kittens, and on animals with a unilateral lesion, suggest that the suppression of PGO inputs to the LGN induced a delay in the electrophysiological maturation of this nucleus.