Thomas Poulsen

Reducing cost of energy in the offshore wind energy industry: The promise and potential of supply chain management

Purpose n n n n nTo support ongoing industry efforts to reduce the cost of energy (CoE) of offshore wind compared to other types of energy sources, researchers are applying scientific models and thought processes to identify potential areas of improvement and optimization. This paper aims to introduce a conceptual framework from a supply chain management (SCM) perspective, aimed at promoting the reduction of CoE in the offshore wind energy industry. n n n n nDesign/methodology/approach n n n n nUsing conceptual arguments from current academic literature in SCM, a comprehensive framework is presented that clarifies how SCM practices can be used by offshore wind energy industry to reduce CoE. n n n n nFindings n n n n nThe offshore wind energy sector is a young industry that must reduce CoE to compete with other forms of energy. Applying a supply chain perspective in the offshore wind industry has hitherto been limited to the academic community. This paper offers a SCM framework that includes three interdependent aspects of reducing CoE – innovation, industrialization and supplier partnering – to guide the industry towards sources to reduce CoE. n n n n nResearch limitations/implications n n n n nSCM is a broad research area; thus, the presented framework to reduce the CoE is open for further development. n n n n nPractical implications n n n n nThe paper provides insights into how the CoE can be reduced through innovation, industrialization and partnering in the offshore wind energy supply chain. n n n n nOriginality/value n n n n nThe paper offers a seminal contribution by introducing a SCM framework to understand sources and approaches to reduce CoE in the offshore wind energy industry.

Interleukin-1α activation and localization in lipopolysaccharide-stimulated human monocytes and macrophages

BACKGROUNDnInterleukin-1α (IL-1α) is a proinflammatory cytokine belonging to the IL-1 family. It is synthesized as a 33kDa precursor peptide that is cleaved by a calpain-like protease to a 16 kDa propiece and a 17 kDa mature IL-1α peptide. In contrast to its close relative, IL-1β, the role of IL-1α in inflammation is only partly understood.nnnRESULTSnHuman monocyte derived macrophages, stimulated with lipopolysaccharide (LPS) were analysed for production and localization of IL-1α by use of a monoclonal antibody (MAb) generated against recombinant precursor IL-1α. We found that the MAb detected IL-1α within the nuclei of the cells 2h (hours) after LPS stimulation and production continued for up to 20 h. At no time could we demonstrate cleavage of the IL-1α precursor. The MAb was conjugated to fluorescein isothiocyanate (FITC) for use in flow cytometry. Based on the flow cytometric analysis CD68 positive cells were positive for IL-1α in agreement with CD68 being a marker for monocytes.nnnCONCLUSIONSnHere, we demonstrate, for the first time, a method to visualize and measure the production of IL-1α in both human monocytes and macrophages.

Proteomic analysis of lipopolysaccharide activated human monocytes

HIGHLIGHTSLC–MS/MS analysis identifies 2746 quantifiable proteins in human monocytes.LPS alters the abundance of 244 proteins.LPS reduces the abundance of several lysosomal proteins.LPS alters the abundance of proteins involved in antigen‐presentation and skews antigen‐presentation towards MHC class I presentation. ABSTRACT Monocytes are key mediators of innate immunity and comprise an important cellular defence against invading pathogens. However, exaggerated or dysregulated monocyte activation can lead to severe immune‐mediated pathology such as sepsis or chronic inflammatory diseases. Thus, detailed insight into the molecular mechanisms of monocyte activation is essential to understand monocyte‐driven inflammatory pathologies. We therefore investigated the global protein changes in human monocytes during lipopolysaccharide (LPS) activation to mimic bacterial activation. Purified human monocytes were stimulated with LPS for 17 h and analyzed by state‐of‐the‐art liquid chromatography tandem mass spectrometry (LC–MS/MS). The label‐free quantitative proteome analysis identified 2746 quantifiable proteins of which 101 had a statistically significantly different abundance between LPS‐stimulated cells and unstimulated controls. Additionally, 143 proteins were exclusively identified in either LPS stimulated cells or unstimulated controls. Functional annotation clustering demonstrated that LPS, most significantly, regulates proteasomal‐ and lysosomal proteins but in opposite directions. Thus, seven proteasome subunits were upregulated by LPS while 11 lysosomal proteins were downregulated. Both systems are critically involved in processing of proteins for antigen‐presentation and together with LPS‐induced regulation of CD74 and tapasin, our data suggest that LPS can skew monocytic antigen‐presentation towards MHC class I rather than MHC class II. In summary, this study provides a sensitive high throughput protein analysis of LPS‐induced monocyte activation and identifies several LPS‐regulated proteins not previously described in the literature which can be used as a source for future studies.

Complement C3 opsonization of Chlamydia trachomatis facilitates uptake in human monocytes

Chlamydia trachomatis is an obligate intracellular bacterium that causes severe infections, which can lead to infertility and ectopic pregnancy. Although both innate and adaptive immune responses are elicited during chlamydial infection the bacterium succeeds to evade host defense mechanisms establishing chronic infections. Thus, studying the host-pathogen interaction during chlamydial infection is of importance to understand how C.xa0trachomatis can cause chronic infections. Both the complement system and monocytes play essential roles in anti-bacterial defense, and, therefore, we investigated the interaction between the complement system and the human pathogens C.xa0trachomatis D and L2. Complement competent serum facilitated rapid uptake of both chlamydial serovars into monocytes. Using immunoelectron microscopy, we showed that products of complement C3 were loosely deposited on the bacterial surface in complement competent serum and further characterization demonstrated that the deposited C3 product was the opsonin iC3b. Using C3-depleted serum we confirmed that complement C3 facilitates rapid uptake of chlamydiae into monocytes in complement competent serum. Complement facilitated uptake did not influence intracellular survival of C.xa0trachomatis or C.xa0trachomatis-induced cytokine secretion. Hence, C.xa0trachomatis D and L2 activate the complement system leading to chlamydial opsonization by iC3b and subsequent phagocytosis, activation and bacterial elimination by human monocytes.

Triple pulse tester — Efficient power loss characterization of power modules

In this paper the triple pulse testing method and circuit for power loss characterization of power modules is introduced. The proposed test platform is able to accurately characterize both the switching and conduction losses of power modules in a single automated process. A configuration of a half bridge is tested by making a sweep of the junction temperature, dc-link voltage, and current for a given gate drive and dc-bus setup. Test results are presented for a 1700 V 1400 A IGBT power module.