Colour changes upon cooling of Lepidoptera scales containing photonic nanoarchitectures

The effects produced by the condensation of water vapours from the ambient in the various intricate nanoarchitectures occurring in the wing scales of several Lepidoptera species were investigated by controlled cooling (from room temperature to -5 - -10 {\deg}C) combined with in situ measurement of changes in the reflectance spectra. It was determined that, due to this procedure, all photonic nanoarchitectures giving a reflectance maximum in the visible range and having an open nanostructure exhibited alteration of the position of the reflectance maximum associated with the photonic nanoarchitectures. The photonic nanoarchitectures with a closed structure exhibited little to no alteration in colour. Similarly, control specimens coloured by pigments did not exhibit a colour change under the same conditions. Hence, this effect can be used to identify species with open photonic nanoarchitectures in their scales. For certain species, an almost complete disappearance of the reflectance maximum was found. All specimens recovered their original colours following warming and drying. Cooling experiments using thin copper wires demonstrated that colour alterations could be limited to a millimetre, or below. Dried museum specimens do not exhibit colour changes when cooled in the absence of a heat sink due to the low heat capacity of the wings.Comment: 18 pages, 9 figures, including supplemen

Smoking decreases the level of circulating CD34+ progenitor cells in young healthy women

Hintergrund: Es wird vermutet, dass die Anzahl zirkulierender Progenitorzellen (PC), insbesondere sogenannter endothelialer Progenitorzellen (EPC), durch Rauchen und weitere kardiovaskuläre Risikofaktoren negativ moduliert wird. Bei prämenopausalen Frauen besteht anderseits ein positiver Einfluss auf die sog. EPC seitens des Östrogens. Zielsetzung: Im Rahmen einer Probandenstudie sollte die Frage beantwortet werden, ob die Anzahl zirkulierender PC bei gesunden prämenopausalen Frauen durch chronisches inhalatives Rauchen unter geringem bzw. starkem Einfluss endogener weiblicher Hormone innerhalb des Menstruationszyklus beeinflusst wird. Des Weiteren sollte untersucht werden, ob die Quantität der PC innerhalb des Menstruationszyklus einer Schwankung unterliegt. Im experimentellen Teil der Arbeit sollte geklärt werden, ob aus CFU-EPC bzw. aus CD34+ PC proliferierende Endothelzellen entstehen können. Materialen und Methoden: Im Rahmen der Probandenstudie wurden die Endothelfunktion sowie die Anzahl der CD34+ und CD34+/CD133+ PC im peripheren Blut mittels FACS Analyse bestimmt. Zusätzlich wurde die Zahl der Colony forming units (CFU-EPC) in Zellkultur ermittelt. Bei 32 Frauen (17 Raucherinnen und 15 Nichtraucherinnen) erfolgten Messungen nur in der Menstruationsphase (3. Tag des Menstruationszyklus). Zusätzlich haben Untersuchungen bei 20 Frauen auch zu Zeitpunkten, wo deutlich stärkerer hormoneller Einfluss besteht, nämlich in der Follikelphase (7. Tag des Menstruationszyklus) und in der Lutealphase (7. Tag vor Beginn der Regelblutung), stattgefunden. Im experimentellen Teil der Arbeit wurden aus peripherem Blut gewonnene mononukleäre Zellen im Standard-Zellkulturmedium (M199+20% FCS) bzw. in angiogenem Zellkulturmedium (EBM mit EGM-2 Bullet Kits) kultiviert. Ferner wurde nach MACS Isolation die Differenzierung der CD34+, CD34- und der unselektierten mononukleären Zellen analysiert. Ergebnisse: Die Zahl der CD34+ PC war in der Rauchergruppe signifikant reduziert, sowohl in der Menstruationsphase als auch in der Follikel- und Lutealphase. Es lag kein signifikanter Unterschied in der Anzahl der untersuchten zirkulierenden PC zwischen den untersuchten Zeitpunkten des Menstruationszyklus vor. Nur die Anzahl der CD34+ PC zeigte eine Korrelation mit der endothelabhängigen Vasodilatation. Aus mononukleären Zellen können zwei Typen endothelartiger Zellen entstehen. Zu der ersten Zellgruppe gehören die Zellen der CFU-EPC, die eher transdifferenzierten Monozyten entsprechen. Die zweite Zellgruppe beinhaltet stark proliferierende Zellen mit Endotheleigenschaften, die mutmaßlich aus CD34+ PC oder abgeschilferten vaskulären Endothelzellen unter Einfluss von Zytokinen und weiteren mononukleären Zellen hervorgehen. Schlussfolgerung: Die Anzahl der CD34+ PC wird bei chronischen Raucherinnen beeinträchtigt, unabhängig von zusätzlichen endogenen hormonellen Einflüssen. Das Ausmaß des Anstiegs von Östrogen reicht in den untersuchten Phasen des Menstruationszyklus nicht aus, um die Anzahl von PC relevant zu beeinflussen. Die CD34+Zellzahl könnte bei gesunden prämenopausalen Frauen einen zusätzlichen Marker für die Endothelfunktion darstellen. Die sogenannten EPC stellen eine heterogene Zellgruppe dar.BACKGROUND: Decreased levels of circulating bone marrow-derived progenitor cells have been associated with risk factors and cardiovascular diseases. Smoking is the most important modifiable risk factor for atherosclerosis in young women. OBJECTIVES: The aim of this pilot study was to assess in healthy premenopausal women without other risk factors for cardiovascular disease the influence of nicotine abuse on the number of circulating progenitor cells in relation to endothelial function. Further was the differentiation of CFU-EPC and CD34 + PC also analyzed, whether they can generate endothelial cells. METHODS: The number of endothelial progenitor cells, measured as colony- forming units in a cell-culture assay (EPC-CFU) and the number of circulating CD34 + and CD34 + /CD133 + cells, measured by flow cytometry, was estimated in 32 women at the menstrual phase of the menstrual cycle. In addition, flow- mediated dilation (FMD) was assessed as a marker for vascular function. In a subgroup of these women (n = 20), progenitor cells were also investigated at the mid-follicular and luteal phases of the menstrual cycle. In the experimental part of this work were peripheral blood mononuclear cells in standard cell culture medium (M199 +20% FCS) or in angiogenic cell culture medium (EBM with EGM-2 Bullet kit) cultivated. After MACS isolation was the differentiation of CD34 +, CD34-and unselected mononuclear cells analyzed. RESULTS: Compared to non-smokers, the abundance of circulating CD34 + cells was significantly lower in smoking women in the menstrual, mid-luteal, and mid-follicular phases of the menstrual cycle. The number of CD34 + progenitor cells was revealed to have significant positive correlation with FMD in young healthy women, whereas CD34 + /CD133 + progenitor cells and EPC-CFU showed no significant correlation. From mononuclear cells, two types of endothelial cells can arise. The first group encloses the colonies of CFU-EPC that share in cell culture and RT-PCR many similar properties with monocytes. The second group contains cells with high proliferative potential and typical endothelial morphology and expression of endothelial marker KDR, CD31, VE-Cadherin and NO synthase. They may arise from CD34 + putative PC or desquamated vascular endothelial cells under the influence of cytokines and other mononuclear cells. CONCLUSION: The number of CD34 + progenitor cells positively correlates with FMD in young healthy women and is decreased by smoking. The CD34 + cell count in healthy premenopausal women could be an additional marker for endothelial function. Endothelial progenitor cells represent a heterogeneous cell population

Cost-Aware IoT Extension of DISSECT-CF

In the age of the Internet of Things (IoT), more and more sensors, actuators and smart devices get connected to the network. Application providers often combine this connectivity with novel scenarios involving cloud computing. Before implementing changes in these large-scale systems, an in-depth analysis is often required to identify governance models, bottleneck situations, costs and unexpected behaviours. Distributed systems simulators help in such analysis, but they are often problematic to apply in this newly emerging domain. For example, most simulators are either too detailed (e.g., need extensive knowledge on networking), or not extensible enough to support the new scenarios. To overcome these issues, we discuss our IoT cost analysis oriented extension of DIScrete event baSed Energy Consumption simulaTor for Clouds and Federations (DISSECT-CF). Thus, we present an in-depth analysis of IoT and cloud related pricing models of the most widely used commercial providers. Then, we show how the fundamental properties (e.g., data production frequency) of IoT entities could be linked to the identified pricing models. To allow the adoption of unforeseen scenarios and pricing schemes, we present a declarative modelling language to describe these links. Finally, we validate our extensions by analysing the effects of various identified pricing models through five scenarios coming from the field of weather forecasting

Simulating IoT Workflows in DISSECT-CF-Fog

The modelling of IoT applications utilising the resources of cloud and fog computing is not straightforward because they have to support various trigger-based events that make human life easier. The sequence of tasks, such as performing a service call, receiving a data packet in the form of a message sent by an IoT device, and managing actuators or executing a computational task on a virtual machine, are often associated with and composed of IoT workflows. The development and deployment of such IoT workflows and their management systems in real life, including communication and network operations, can be complicated due to high operation costs and access limitations. Therefore, simulation solutions are often applied for such purposes. In this paper, we introduce a novel simulator extension of the DISSECT-CF-Fog simulator that leverages the workflow scheduling and its execution capabilities to model real-life IoT use cases. We also show that state-of-the-art simulators typically omit the IoT factor in the case of the scientific workflow evaluation. Therefore, we present a scalability study focusing on scientific workflows and on the interoperability of scientific and IoT workflows in DISSECT-CF-Fog

Modeling Dew Computing in DISSECT-CF-Fog

Fog computing provides an effective solution to various problems by extending the cloud’s functionality to typically more limited computing units closer to user devices. Fog computing can provide a higher level of user experience due to its geographic and network topology location and distribution. IoT services also need to be managed seamlessly to ensure adequate QoS (due to the mobility of devices or the temporary periods without an internet connection). Such domains are combined under the auspices of Dew computing, as in critical cases, extending an IoT service to the end user’s device is a feasible task. Such scenarios can hardly be investigated at a large scale due to the lack of dedicated simulation environments. In this paper, we present an extension of the DISSECT-CF-Fog simulator with a Dew computing model, to enable the simulation of IoT-Dew-Fog systems in a cost-effective manner. In particular, we focus on service migration options for mobile devices and cases with temporary internet access limitations. Finally, we performed measurements of real-world use cases with the extended simulator as an evaluation. Our simulation results show that the proposed proactive strategy reduces the processing time of IoT data, exploiting an IoT-Dew-Fog environment

Smoking decreases the level of circulating CD34+ progenitor cells in young healthy women - a pilot study

Abstract Background Decreased levels of circulating bone marrow-derived progenitor cells have been associated with risk factors and cardiovascular diseases. Smoking is the most important modifiable risk factor for atherosclerosis in young women. The aim of this pilot study was to assess in healthy premenopausal women without other risk factors for cardiovascular disease the influence of nicotine abuse on the number of circulating progenitor cells in relation to endothelial function. Methods The number of endothelial progenitor cells, measured as colony-forming units in a cell-culture assay (EPC-CFU) and the number of circulating CD34 + and CD34 + /CD133 + cells, measured by flow cytometry, was estimated in 32 women at the menstrual phase of the menstrual cycle. In addition, flow-mediated dilation (FMD) was assessed as a marker for vascular function. In a subgroup of these women (n = 20), progenitor cells were also investigated at the mid-follicular and luteal phases of the menstrual cycle. Results Compared to non-smokers, the abundance of circulating CD34 + cells was significantly lower in smoking women in the menstrual, mid-luteal, and mid-follicular phases of the menstrual cycle. The number of CD34 + progenitor cells was revealed to have significant positive correlation with FMD in young healthy women, whereas CD34 + /CD133 + progenitor cells and EPC-CFU showed no significant correlation. Conclusion The number of CD34 + progenitor cells positively correlates with FMD in young healthy women and is decreased by smoking.</p