The accommodation coefficient of water molecules on ice -cirrus cloud studies at the AIDA simulation chamber

Cirrus clouds and their impact on the Earth's radiative budget are subjects of current research. The processes governing the growth of cirrus ice particles are central to the radiative properties of cirrus clouds. At temperatures relevant to cirrus clouds, the growth of ice crystals smaller than a few microns in size is strongly influenced by the accommodation coefficient of water molecules on ice, αice, making this parameter relevant for cirrus cloud modeling. However, the experimentally determined magnitude of αice for cirrus temperatures is afflicted with uncertainties of almost three orders of magnitude, and values for αice derived from cirrus cloud data lack significance so far. This has motivated dedicated experiments at the cloud chamber AIDA (Aerosol Interactions and Dynamics in the Atmosphere) to determine αice in the cirrus-relevant temperature interval between 190 K and 235 K under realistic cirrus ice particle growth conditions. The experimental data sets have been evaluated independently with two model approaches: the first relying on the newly developed model SIGMA (Simple Ice Growth Model for determining Alpha), the second one on an established model, ACPIM (Aerosol-Cloud-Precipitation Interaction Model). Within both approaches a careful uncertainty analysis of the obtained αice values has been carried out for each AIDA experiment. The results show no significant dependence of αice on temperature between 190 K and 235 K. In addition, we find no evidence for a dependence of αice on ice particle size or on water vapor supersaturation for ice particles smaller than 20 μm and supersaturations of up to 70%. The temperature-averaged and combined result from both models is αice = 0.7−0.5+0.3, which implies that αice may only exert a minor impact on cirrus clouds and their characteristics when compared to the assumption of αice =1. Impact on prior calculations of cirrus cloud properties, e.g., in climate models, with αice typically chosen in the range 0.2–1 is thus expected to be negligible. In any case, we provide a well-constrained αice which future cirrus model studies can rely on

STAT3 Regulates Monocyte TNF-Alpha Production in Systemic Inflammation Caused by Cardiac Surgery with Cardiopulmonary Bypass

BACKGROUND: Cardiopulmonary bypass (CPB) surgery initiates a controlled systemic inflammatory response characterized by a cytokine storm, monocytosis and transient monocyte activation. However, the responsiveness of monocytes to Toll-like receptor (TLR)-mediated activation decreases throughout the postoperative course. The purpose of this study was to identify the major signaling pathway involved in plasma-mediated inhibition of LPS-induced tumor necrosis factor (TNF)-α production by monocytes. METHODOLOGY/PRINCIPAL FINDINGS: Pediatric patients that underwent CPB-assisted surgical correction of simple congenital heart defects were enrolled (n = 38). Peripheral blood mononuclear cells (PBMC) and plasma samples were isolated at consecutive time points. Patient plasma samples were added back to monocytes obtained pre-operatively for ex vivo LPS stimulations and TNF-α and IL-6 production was measured by flow cytometry. LPS-induced p38 mitogen-activated protein kinase (MAPK) and nuclear factor (NF)-κB activation by patient plasma was assessed by Western blotting. A cell-permeable peptide inhibitor was used to block STAT3 signaling. We found that plasma samples obtained 4 h after surgery, regardless of pre-operative dexamethasone treatment, potently inhibited LPS-induced TNF-α but not IL-6 synthesis by monocytes. This was not associated with attenuation of p38 MAPK activation or IκB-α degradation. However, abrogation of the IL-10/STAT3 pathway restored LPS-induced TNF-α production in the presence of suppressive patient plasma. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that STAT3 signaling plays a crucial role in the downregulation of TNF-α synthesis by human monocytes in the course of systemic inflammation in vivo. Thus, STAT3 might be a potential molecular target for pharmacological intervention in clinical syndromes characterized by systemic inflammation

The study of atmospheric ice-nucleating particles via microfluidically generated droplets

Ice-nucleating particles (INPs) play a significant role in the climate and hydrological cycle by triggering ice formation in supercooled clouds, thereby causing precipitation and affecting cloud lifetimes and their radiative properties. However, despite their importance, INP often comprise only 1 in 10³–10⁶ ambient particles, making it difficult to ascertain and predict their type, source, and concentration. The typical techniques for quantifying INP concentrations tend to be highly labour-intensive, suffer from poor time resolution, or are limited in sensitivity to low concentrations. Here, we present the application of microfluidic devices to the study of atmospheric INPs via the simple and rapid production of monodisperse droplets and their subsequent freezing on a cold stage. This device offers the potential for the testing of INP concentrations in aqueous samples with high sensitivity and high counting statistics. Various INPs were tested for validation of the platform, including mineral dust and biological species, with results compared to literature values. We also describe a methodology for sampling atmospheric aerosol in a manner that minimises sampling biases and which is compatible with the microfluidic device. We present results for INP concentrations in air sampled during two field campaigns: (1) from a rural location in the UK and (2) during the UK’s annual Bonfire Night festival. These initial results will provide a route for deployment of the microfluidic platform for the study and quantification of INPs in upcoming field campaigns around the globe, while providing a benchmark for future lab-on-a-chip-based INP studies

Let the games begin: Finding the nascent entrepreneurial mindset of video gamers

This study explores nascent ‘entrepreneurial’ cognitive factors within the minds of video gamers. The objective is to theorize how certain gamification activities might be designed to enable the development of entrepreneurial behavior. While studies have begun to posit the range cognitive factors that result in the emergence of entrepreneurial action, more conceptualization work is needed to understand nascent conditions and activities that might foster the entrepreneurial mindset; especially within the gaming design context. This exploratory study uses a sample of 217 self-reported gamers and suggests that individuals who exhibit high levels of entrepreneurial orientation have enhanced opportunity recognition capabilities when the frequency of playing video games is also high. It was also found that shooting games have the highest effect on the development of opportunity recognition. This suggests that certain game activities may be designed to enhance entrepreneurial cognitive development; which has implications for the entrepreneurial intent literature and game-designers

Understanding human genetic factors influencing primaquine safety and efficacy to guide primaquine roll-out in a pre-elimination setting in southern Africa

Contains fulltext : 190993.pdf (publisher's version ) (Open Access)BACKGROUND: Primaquine (PQ) is recommended as an addition to standard malaria treatments in pre-elimination settings due to its pronounced activity against mature Plasmodium falciparum gametocytes, the parasite stage responsible for onward transmission to mosquitoes. However, PQ may trigger haemolysis in glucose-6-phosphate dehydrogenase (G6PD)-deficient individuals. Additional human genetic factors, including polymorphisms in the human cytochrome P450 2D6 (CYP2D6) complex, may negatively influence the efficacy of PQ. This study assessed the prevalence of G6PD deficiency and two important CYP2D6 variants in representative pre-elimination settings in South Africa, to inform malaria elimination strategies. METHODS: Volunteers (n = 248) attending six primary health care facilities in a malaria-endemic region of South Africa were enrolled between October and November 2015. G6PD status was determined phenotypically, using a CareStart G6PD rapid diagnostic test (RDT), and genotypically for two common African G6PD variants, namely A+ (A376G) and A- (G202A, A542T, G680T & T968C) by PCR, restriction fragment length polymorphisms (RFLP) and DNA sequencing. CYP2D6*4 and CYP2D6*17 variants were determined with PCR and RFLP. RESULTS: A prevalence of 13% (33/248) G6PD deficiency was observed in the cohort by G6PD RDT whilst by genotypic assessment, 32% (79/248) were A+ and 3.2% were A-, respectively. Among the male participants, 11% (6/55) were G6PD A- hemizygous; among females 1% (2/193) were G6PD A- homozygous and 16% (32/193) G6PD A- heterozygous. The strength of agreement between phenotyping and genotyping result was fair (Cohens Kappa kappa = 0.310). The negative predictive value for the G6PD RDT for detecting hemizygous, homozygous and heterozygous individuals was 0.88 (95% CI 0.85-0.91), compared to the more sensitive genotyping. The CYP2D6*4 allele frequencies for CYP2D6*4 (inferred poor metabolizer phenotype) and CYP2D6*17 (inferred intermediate metabolizer phenotype) were 3.2 and 19.5%, respectively. CONCLUSIONS: Phenotypic and genotypic analyses both detected low prevalence of G6PD deficiency and the CYP2D6*4 variants. These findings, combined with increasing data confirming safety of single low-dose PQ in individuals with African variants of G6PD deficiency, supports the deployment of single low-dose PQ as a gametocytocidal drug. PQ would pose minimal risks to the study populations and could be a useful elimination strategy in the study area

Multilevel marketing: Optimizing marketing effectiveness for high-involvement goods in the automotive industry

With a surge in communication channels increasing the complexity of today’s media landscape, companies face new challenges concerning the allocation of their advertising budget. As consumers become increasingly more autonomous in gathering information from the channels they deem most suitable, they encounter several touchpoints on their customer journey. Marketers struggle with the assessment of channel effectiveness. Despite a rise in research on the topic of attribution, findings and methodology vary greatly regarding variables and outcomes. The question of how to determine suitable attribution modeling that optimizes advertising effectiveness thus remains unanswered. This article aims at assessing which factors influence channel effectiveness in the context of high-involvement goods. Based on a unique dataset from a multinational car manufacturer, a Structural Vector Autoregressive model has been formulated revealing channel interactions, lagged effects of advertising and conversion funnel stages as being highly influential factors concerning channel effectiveness

Let the games begin: The relationship between video gaming and entrepreneurial mindsets

This article addresses the need for further conceptual development of the factors that influence the development of the entrepreneurial mindset. It focuses on finding a link between the classic mental models of entrepreneurship and those that are employed during video game play to explore if similarities exist. Using theories of entrepreneurship and opportunity recognition, the study examines a sample of 217 self-reported gamers. The results of this study suggest that an individual who exhibits a high level of entrepreneurial orientation has an enhanced opportunity recognition capability when the intensity of playing video games is also high. Various genres of games were controlled for; however, it was found that shooting games have the highest effect on the emergence of opportunity recognition. Thus, the study reveals that some game activities can be linked to entrepreneurial cognitions and potentially also development; which has implications for the entrepreneurial intent literature, as well as practical implications for game-designers and managers

Designing coopetition for radical innovation: An experimental study of managers' preferences for developing self-driving electric cars

The major premise of this study is that managers purposefully shape the business context for radical innovation. Particularly, the strategic option of developing radical innovation in collaboration with direct competitors offers opportunities otherwise unattainable. We tap into its cognitive underpinnings by running an experimental study of coopetition design for radical innovation. We have collected 5760 binary decisions from a sample of 160 managers. Their indications are used to run a choice-based conjoint analysis in order to identify utilities attributed to coopetition-shaping decisions in a radical innovation project (using a scenario of self-driving/electric cars produced by VW, Daimler or Tesla). We use Hierarchical Bayes Multinomial Logit Regression to test a set of four hypotheses, each addressing a different coopetition factor to unveil manager's preferences in coopetition design for radical innovation. Our findings pinpoint a clear preference for network coopetition, using formal governance, and being based on intensive knowledge sharing. Contrary to prior literature, market uncertainty does not appear to significantly influence coopetition design for radical innovation

Family firm entrepreneurship: An experimental study

Family managers' entrepreneurial intentions (EI) play a crucial role in the long-term success of family firms. Previous research has highlighted education as a key driver of EI but has failed to consider the unique socialization processes within business families and their impact on the education-EI relationship. This study aims to fill this gap by examining the direct and indirect effects of education on family managers' EI. By combining the integrated model of EI and research on business families' socialization patterns, a study was conducted with a role-playing experimental design involving 412 family firm managers. The results indicate that entrepreneurial self-efficacy (ESE) serves as a mediator between education and EI, while the ESE-EI relationship is further mediated by risk perceptions. Interestingly, no direct effect of education on EI was found, suggesting that the influence of education on EI follows distinct patterns within business families

Digitalization in the financial industry: A contingency approach of entrepreneurial orientation and strategic vision on digitalization

Technology is rapidly changing the financial industry. Banks, in particular, are faced with a shift from traditional, interpersonal forms of service to digital financial services. These digital technologies are more and more becoming today's standard in the banking sector, they challenge traditional business models, and they provide opportunities for banks to capitalize on. Building on the concept of entrepreneurial orientation (EO), this study of banks in Germany, Switzerland, and Liechtenstein aims at developing insights that explain how banks can use the tactics and strategies associated with EO to achieve superior performance in the digitalization age. The results from a survey in 102 banks show that: 1) banks that display high levels of EO report a higher level of performance, and 2) the relationship between a banks' strategic vision on digitalization, and performance is moderated by EO. These results indicate that the sheer level of the digitalization of a bank does not affect profitability. Instead, in this time of technological change banks should develop a clear vision on digitalization that is characterized by innovation, being ahead of the competition, and a willingness to take risks