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The coculture of osteogenic and angiogenic cells and the resulting paracrine signaling via soluble factors are supposed to be crucial for successfully engineering vascularized bone tissue equivalents. In this study, a coculture system combining primary human adiposederived stem cells (hASCs) and primary human dermal microvascular endothelial cells (HDMECs) within two types of hydrogels based on methacryloyl‐modified gelatin (GM) as three‐dimensional scaffolds was examined for its support of tissue specific cell functions. HDMECs, together with hASCs as supporting cells, were encapsulated in soft GM gels and were indirectly cocultured with hASCs encapsulated in stiffer GM hydrogels additionally containing methacrylate‐modified hyaluronic acid and hydroxyapatite particles. After 14 days, the hASC in the stiffer gels (constituting the “bone gels”) expressed matrix proteins like collagen type I and fibronectin, as well as bone‐specific proteins osteopontin and alkaline phosphatase. After 14 days of coculture with HDMEC‐laden hydrogels, the viscoelastic properties of the bone gels were significantly higher compared with the gels in monoculture. Within the soft vascularization gels, the formed capillary‐like networks were significantly longer after 14 days of coculture than the structures in the control gels. In addition, the stability as well as the complexity of the vascular networks was significantly increased by coculture. We discussed and concluded that osteogenic and angiogenic signals from the culture media as well as from cocultured cell types, and tissue‐specific hydrogel composition all contribute to stimulate the interplay between osteogenesis and angiogenesis in vitro and are a basis for engineering vascularized bone.
Melamine–formaldehyde (MF) resins are widely used as adhesives and finishing materials in the wood industry. During resin cure, either methylene ether or methylene bridges are formed, leading to the formation of a three‐dimensional resin network. Not only the curing degree, but also the chemical species present in the cured resin determine the quality of the final product. Analytical methods allowing a detailed investigation of network formation are of great benefit to manufacturers. In the present work, resin cure of an MF precondensate is studied at different temperatures (100–200 °C) without considering the initial pH as a factor. Isoconversional kinetic analysis based on exothermal curing enthalpies enables calculation of the crosslinking degree at a given time/temperature regime. A semiquantitative determination of the chemical groups present is performed based on solid‐state nuclear magnetic resonance data. Fourier transform infrared spectroscopy has shown to be a fast and reliable analytical tool with high sensitivity toward functional groups and with great potential for at‐line process control.
During curing of thermosetting resins the technologically relevant properties of binders and coatings develop. However, curing is difficult to monitor due to the multitude of chemical and physical processes taking place. Precise prediction of specific technological properties based on molecular properties is very difficult. In this study, the potential of principal component analysis (PCA) and principal component regression (PCR) in the analysis of Fourier transform infrared (FTIR) spectra is demonstrated using the example of melamine-formaldehyde (MF) resin curing in solid state. FTIR/PCA-based reaction trajectories are used to visualize the influence of temperature on isothermal cure. An FTIR/PCR model for predicting the hydrolysis resistance of cured MF resin from their spectral fingerprints is presented which illustrates the advantages of FTIR/PCR compared to the combination differential scanning calorimetry/isoconversional kinetic analysis. The presented methodology is transferable to the curing reactions of any thermosetting resin and can be applied to model other technologically relevant final properties as well.
Natural wood colors occur within a wide range from almost white (e.g., white poplar), various yellowish, reddish, and brownish hues to almost black (e.g., ebony). The intrinsic color of wood is basically defined by its chemical composition. However, other factors such as specific anatomical formations or physical properties further affect the optical impression. Starting with the chemical composition of wood and anatomical basics, wood color and its modifications are discussed in this chapter. The classic method of coloring or re-coloring wood-based material surfaces is the application of a coating containing appropriate dyes or pigments. Different concepts for wood coating and coloration are presented. Another method used dyes for coloration of the wood structure. As alternative techniques, physical methods, for example, drying, steaming, ammoniation, bleaching, enzyme treatment, as well as treatment with electromagnetic irradiation (e.g., UV), are explained in this chapter.
This study investigates how integrated reporting (IR) creates value for investors. It examines how providers of financial capital benefit from an improved firm information environment provided by IR. Specifically, this study investigates the effect of voluntary IR disclosure on analyst earnings forecast accuracy as well as on firm value. To do so, we use an international sample of 167 listed companies that voluntarily publish an integrated report. Our analysis shows no significant effect of a voluntary IR publication on analyst earnings forecast accuracy and no significant effect on firm value. We thus do not find evidence for the fulfillment of IR's promises regarding improved information environment and value creation of voluntary adopters. We conclude that such companies might already have a relatively high level of transparency leading to an absent additional effect of IR disclosure. Positive effects of IR appear to be more relevant in environments where IR is mandatory.
Artificial adipose tissue (AT) constructs are urgently needed to treat severe wounds, to replace removed tissue, or for the use as in vitro model to screen for potential drugs or study metabolic pathways. The clinical translation of products is mostly prevented by the absence of a vascular component that would allow a sustainable maintenance and an extension of the construct to a relevant size. With this study, we aimed to evaluate the suitability of a novel material based on bacterial cellulose (CBM) on the defined adipogenic differentiation of human adipose-derived stem cells (ASCs) and the maintenance of the received adipocytes (diffASCs) and human microvascular endothelial cells (mvECs) in mono- and coculture. A slight acceleration of adipogenic differentiation over regular tissue culture polystyrene (TCPS) was seen on CBM under defined conditions, whereas on the maintenance of the generated adipocytes, comparable effects were detected for both materials. CBM facilitated the formation of vascular like structures in monoculture of mvECs, which was not observed on TCPS. By contrast, vascular-like structures were detected in CBM and TCPS in coculture by the presence of diffASCs. Concluding, CBM represents a promising material in vascularized AT engineering with the potential to speed up and simplify the in vitro setup of engineered products.
Software is an integrated part of new features within the automotive sector, car manufacturers, the Hersteller Initiative Software (HIS) consortium defined metrics to determine software quality. Yet, problems with assigning metrics to quality attributes often occur in practice. The specified boundary values lead to discussions between contractors and clients as different standards and metric sets are used. This paper studies metrics used in the automotive sector and the quality attributes they address. The HIS, ISO/IEC 25010:2011, and ISO/IEC 26262:2018 are utilized to draw a big picture illustrating (i) which metrics and boundary values are reported in literature, (ii) how the metrics match the standards, (iii) which quality attributes are addressed, and (iv) how the metrics are supported by tools. Our findings from analyzing 38 papers include a catalog of 112 metrics of which 17 define boundary values and 48 are supported by tools. Most of the metrics are concerned with source code, are generic, and not specifically designed for automotive software development. We conclude that many metrics exist, but a clear definition of the metrics' context, notably regarding the construction of flexible and efficient measurement suites, is missing.
Escherichia coli (E. coli) is considered the most common life-threatening infectious bacteria in our daily life and poses a major challenge to human health. However, antibiotics frequently overused and misused has triggered increased multidrug resistance, hinders therapeutic outcomes, and causes higher mortalities. Herein, we addressed near-infrared (NIR) laser-excited human serum albumin (HSA) mediated graphene oxide loaded palladium nano-dots (HSA-GO-Pd) that can effectively combat Gram-negative E. coli in vitro. NIR laser-excited designed hybrid material highly generates singlet oxygen and hydroxyl radical by electron spin-resonance (ESR) analysis. Transmission electron microscope (TEM) images show small spherical sizes PdNPs on the surface of GO nano-sheets. The zeta (ζ) potential study indicates that in an aqueous medium, the average PdNPs size and surface capped charge comes from human body protein (HSA), HSA-GO-Pd is 5–8 nm, and +25 mV, respectively. The spectroscopic characterization reveals that in the synthesized HSA-GO-Pd nanocomposite, PdNPs successfully well-dispersed decorated on the surface of graphene oxide. The as-synthesized HSA-GO-Pd shows excellent antibacterial activity against gram-negative pathogen by killing 95% bacteria within 5 h. HSA-GO-Pd having very biocompatible and shows significant antibacterial activities. Owing to their intense photothermal conversation potential, low toxicity to normal cells, the as-addressed hybrid (HSA-GO-Pd) combined with NIR-irradiation will catch up valuable insight into the effective ablation of pathogenic bacteria.
Contemporary public enterprises differ from their forebears. Today, they are more similar to private enterprises, receiving far more attention than previously, when privatization processes all over the world were in the spotlight. Furthermore, the broad research stream of entrepreneurship has so far neglected the consideration of public enterprises. To set a future research agenda, the author examines the dispersed literature using an integrative and organizing framework to identify major topics and research findings. This paper reviews articles that investigate the entrepreneurship in contemporary public enterprises. Despite the growing scholarly interest globally, this systematic literature review indicates there is no more than a loose connection between the literature streams of public entrepreneurship and corporate entrepreneurship. Specifically, the review shows that the multidimensional concept of entrepreneurial orientation has thus far been ignored, although autonomy plays a significant role in the literature review, namely in the context of the interference of the public owner. It also reveals other essential research gaps, such as the development of a modern theory of public enterprises. The linked research stream of public-sector corporate entrepreneurship offers a broad area of scholarly research and should encourage further investigation.
Hardly any software development process is used as prescribed by authors or standards. Regardless of company size or industry sector, a majority of project teams and companies use hybrid development methods (short: hybrid methods) that combine different development methods and practices. Even though such hybrid methods are highly individualized, a common understanding of how to systematically construct synergetic practices is missing. In this article, we make a first step towards a statistical construction procedure for hybrid methods. Grounded in 1467 data points from a large‐scale practitioner survey, we study the question: What are hybrid methods made of and how can they be systematically constructed? Our findings show that only eight methods and few practices build the core of modern software development. Using an 85% agreement level in the participants' selections, we provide examples illustrating how hybrid methods can be characterized by the practices they are made of. Furthermore, using this characterization, we develop an initial construction procedure, which allows for defining a method frame and enriching it incrementally to devise a hybrid method using ranked sets of practice.
Management and cost accounting has been the basic toolbox in business administration for decades. Today it is an integral part of all curricula in business education and no student can afford not to be familiar with its basic concepts and instruments. At the same time, business in general, and management accounting in particular, is becoming more and more international. English clearly has evolved as the „lingua franca“ of international business. Academics, students as well as practitioners exchange their views and ideas, discuss concepts and communicate with each other in English. This is certainly also true for cost accounting and management accounting.
In this study, a novel strategy has been developed for the assembly of polyelectrolyte multilayer (PEM) on CaCO3 templates in acidic pH solutions, where consecutive polyelectrolyte layers (heparin/poly(allylamine hydrochloride) or heparin/chitosan) were deposited on PEM hollow microcapsules established previously on CaCO3 templates. The PEM build-up, hollow capsule characterization and successful encapsulation of fluorescein 5(6)-isothiocyanate (FITC)-Dextran by coprecipitation with CaCO3 are demonstrated. Improvement by the removal of CaCO3 core was achieved while the depositions. In the course of the release profile, high retardation for encapsulated FITC-Dextran was observed. The combined shell capsules system is a significant trait that has potential use in tailoring functional layer-by-layer capsules as intelligent drug delivery vehicles where the preliminary in vitro tests showed the responsiveness on the enzymes.
Why are organizations and markets slow to transform toward sustainability despite the abundant well-recognized opportunities it provides? An important subset of the phenomena this question addresses involves decision-makers recognizing the existence of opportunities but failing to undertake ambitious, effective, sufficient, or timely action. Building on existing research on capability traps, market formation, and managing sustainability, we focus on the forces con-straining organizations from developing the capabilities and market infrastructures required for sustainability transformations. We characterize types of sustainability initiatives and, using causal loop diagramming, visualize structures that enable and constrain how organizations can navigate individually and collectively worse-before-better dynamics resulting from uncertain,nonlinear, and delayed returns. Being under day-to-day pressures and deeply intertwined within their environment, organizational actors find it difficult to recognize, undertake, maintain, and coordinate necessary efforts internally and externally. We discuss research implications and directions for future research on avoiding these traps and accelerating sustainability transformations.
Positively charged metallic oxides prevent blood coagulation whereas negatively charged metallic oxides are thrombogenic. This study was performed to examine whether this effect extends to metallic oxide nanoparticles. Oscillation shear rheometry was used to study the effect of zinc oxide and silicon dioxide nanoparticles on thrombus formation in human whole blood. Our data show that oscillation shear rheometry is a sensitive and robust technique to analyze thrombogenicity induced by nanoparticles. Blood without previous contact with nanoparticles had a clotting time (CT) of 16.7 ± 1.0 min reaching a maximal clot strength (CS) of 16 ± 14 Pa (G') after 30 min. ZnO nanoparticles (diameter 70 nm, +37 mV zeta-potential) at a concentration of 1 mg/mL prolonged CT to 20.8 ± 3.6 min and provoked a weak clot (CS 1.5 ± 1.0 Pa). However, at a lower concentration of 100 µg/mL the ZnO particles dramatically reduced CT to 6.0 ± 0.5 min and increased CS to 171 ± 63 Pa. This procoagulant effect decreased at lower concentrations reaching the detection limit at 10 ng/mL. SiO2 nanoparticles (diameter 232 nm, −28 mV zeta-potential) at high concentrations (1 mg/mL) reduced CT (2.1 ± 0.2 min) and stimulated CS (249 ± 59 Pa). Similar to ZnO particles, this procoagulant effect reached a detection limit at 10 ng/mL. Nanoparticles in high concentrations reproduce the surface charge effects on blood coagulation previously observed with large particles or solid metal oxides. However, nanoparticles with different surface charges equally well stimulate coagulation at lower concentrations. This stimulation may be an effect which is not directly related to the surface charge.
Melamine-formaldehyde resins are widely used for decorative paper impregnation. Resin properties relevant for impregnation are mainly determined already at the stage of resin synthesis by the applied reaction conditions. Thus, understanding the relationship between reaction conditions and technological properties is important. Response surface methodology based on orthogonal parameter level variations is the most suitable tool to identify and quantify factor effects and deduce causal correlation patterns. Here, two major process factors of MF resin synthesis were systematically varied using such a statistical experimental design. To arrive at resins having a broad range of technological properties, initial pH and M:F ratio were varied in a wide range (pH: 7.9–12.1; M:F ratio: 1:1.5–1:4.5). The impregnation behavior of the resins was modeled using viscosity, penetration rate and residual curing capacity as technological responses. Based on the response surface models, nonlinear and synergistic action of process factors was quantified and a suitable process window for preparing resins with favorable impregnation performance was defined. It was found that low M:F ratios (~1:2–1:2.5) and comparatively high starting pHs (~pH 11) yield impregnation resins with rapid impregnation behavior and good residual curing capacity.
The dynamic capabilities perspective is aimed at explaining how firms achieve and sustain competitive advantages, especially in environments that become volatile, uncertain, complex, and ambiguous (VUCA). In this paper, we combine factors that explain dynamic capabilities on the firm level with factors of dynamic managerial capabilities on the individual level. In addition to the dynamic capabilities theory, we draw on corporate foresight (CF) literature to test the impact of CF training. We find that both the organizational-level practices and the individual-level training of leaders are positively associated with firm-level outcomes. We further observe that this relationship is mediated by dynamic managerial capabilities (i.e., the ability of leaders to challenge current business models, make decisions under uncertainty, and reconfigure organizational resources). Our findings emphasize the importance of training leaders and building organizational CF practices to build the dynamic capabilities needed in VUCA environments.
It is known that the costs related with drug research and development (R&D) and the timelines to develop a new drug increased over the past years. In parallel, the success rates of drug projects along the pharmaceutical R&D phases are still very low, and the outcome of all R&D efforts is stagnating. In consequence, the R&D efficiency defined as the financial investment per drug has been steadily decreasing. As innovation is the major growth driver of the pharmaceutical industry, reliable data on R&D efficiency and new concepts to overcome these challenges are of great interest for R&D managers and the sustainability of the pharmaceutical industry as a whole. This book chapter reviews publications on R&D performance indicators of the past years, such as the success rates and timelines per phase. Additionally, it illustrates the factors influencing the success rates, timelines, and costs of pharmaceutical R&D most and, thus, the denominators of the R&D efficiency.
The efficiency of pharmaceutical research and development (R&D) reflected by increasing costs of R&D, long timelines, and low probabilities of technical and regulatory success decreased continuously in the past years. Today, the costs for discovering and developing a new drug are enormously high with more than USD 2 billion per new molecular entity (NME), while the average overall success of a research project to provide an NME is in the single-digit percentage rate, and the total timelines of R&D easily exceeds 10 years questioning the return on investment (ROI) of pharmaceutical R&D. As a consequence and also caused by numerous patent expirations of blockbuster drugs that increased the pressure to return to an acceptable ROI, the pharmaceutical industry addressed this challenge and the related causes and identified several actions that need to be taken to increase the output/input ratio of R&D. This book chapter will review the pipeline sizes and the R&D investments of multinational pharmaceutical companies, will describe new processes that have been implemented to increase the reach and to reduce costs of pharmaceutical R&D, and it will illustrate new innovation models that were developed to increase the R&D efficiency.
The reduced research and development (R&D) efficiency, strong competition from generics, increased cost pressure from payers, and an increased biological complexity of new target indications have resulted in a rethinking and a change from a traditional and more closed R&D model in the pharmaceutical industry toward the new paradigm of open innovation. In the past years, pharmaceutical companies have broadened their external networks toward research collaborations with academic institutes, technology providers, or codevelopment partners. To fulfill the demand to reduce timelines and costs, research-based pharmaceutical companies started to outsource R&D activities. In addition, internal R&D processes were adjusted to the more open R&D model and new processes such as alliance management were established. The corporate frontier of pharmaceutical companies became permeable and more open. As a result, the focus of pharmaceutical R&D expanded from a purely internal toward a mixed internal and external model. Today, the U.S. pharmaceutical company Eli Lilly may have established the most open model toward external innovation, as it has integrated its innovation processes with its business model. Other companies are following this more open R&D model with newer concepts such as new frontier sciences, drug discovery alliances, private public partnerships, innovation incubators, virtual R&D, crowdsourcing, open source innovation, and innovation camps.
BWL Basiswissen
(2010)
Fundierte Entscheidungen im Unternehmen verlangen ein solides BWL-Wissen - egal ob im Marketing, im Controlling, in der Finanzplanung, im Personalwesen oder im strategischen Management. Doch nicht jeder Praktiker im Unternehmen besitzt diese Kenntnisse. Professor Dr. Ottmar Schneck hat alle wichtigen Aspekte zusammengefasst: von den klassischen Themen des Managements über die Geschichte und die Entwicklung der Betriebswirtschaftslehre bis hin zu den aktuellen Ansätzen der modernen BWL. Die Inhalte sind systematisch und praxisnah dargestellt - Übersichten, Fallbeispiele, kurze Zusammenfassungen und Übungen am Ende jedes Kapitels erleichtern die Wissensaneignung.