Stability range of parameters at fixed points for a class of complex dynamics

We study the parameters range for the fixed point of a class of complex dynamics with the rational fractional function as $R_{n,a,c}(z)=z^n+\frac{a}{z^n}+c$, where $n=1,2,3,4$ is specified, $a$ and $c$ are two complex parameters. The relationship between two parameters, $a$ and $c$, is obtained at the fixed point. Moreover the explicit expression of the parameter $a$ and $c$ in terms of $\lambda$ is derived, where $\lambda$ is the derivative function at fixed point. The parameter regimes for the stability of the fixed point are presented numerically for some typical different cases.Comment: 15 pages, 6 figure

Transcriptome Analysis of Aedes aegypti Transgenic Mosquitoes with Altered Immunity

The mosquito immune system is involved in pathogen-elicited defense responses. The NF-κB factors REL1 and REL2 are downstream transcription activators of Toll and IMD immune pathways, respectively. We have used genome-wide microarray analyses to characterize fat-body-specific gene transcript repertoires activated by either REL1 or REL2 in two transgenic strains of the mosquito Aedes aegypti. Vitellogenin gene promoter was used in each transgenic strain to ectopically express either REL1 (REL1+) or REL2 (REL2+) in a sex, tissue, and stage specific manner. There was a significant change in the transcript abundance of 297 (79 up- and 218 down-regulated) and 299 (123 up- and 176 down-regulated) genes in fat bodies of REL1+ and REL2+, respectively. Over half of the induced genes had predicted functions in immunity, and a large group of these was co-regulated by REL1 and REL2. By generating a hybrid transgenic strain, which ectopically expresses both REL1 and REL2, we have shown a synergistic action of these NF-κB factors in activating immune genes. The REL1+ immune transcriptome showed a significant overlap with that of cactus (RNAi)-depleted mosquitoes (50%). In contrast, the REL2+ -regulated transcriptome differed from the relatively small group of gene transcripts regulated by RNAi depletion of a putative inhibitor of the IMD pathway, caspar (35 up- and 140 down-regulated), suggesting that caspar contributes to regulation of a subset of IMD-pathway controlled genes. Infections of the wild type Ae. aegypti with Plasmodium gallinaceum elicited the transcription of a distinct subset of immune genes (76 up- and 25 down-regulated) relative to that observed in REL1+ and REL2+ mosquitoes. Considerable overlap was observed between the fat body transcriptome of Plasmodium-infected mosquitoes and that of mosquitoes with transiently depleted PIAS, an inhibitor of the JAK-STAT pathway. PIAS gene silencing reduced Plasmodium proliferation in Ae. aegypti, indicating the involvement of the JAK-STAT pathway in anti-Plasmodium defense in this infection model

Microbial electrochemical systems for sustainable biohydrogen production: Surveying the experiences from a start-up viewpoint

The start-up of microbial electrohydrogenesis cells (MECs) is a key-step to realize efficient biohydrogen generation and adequate, long-term operation. This review paper deals with the lessons and experiences reported on the most important aspects of H2 producing MEC start-up. The comprehensive survey covers the assessment and discussion of the main influencing factors and methods (e.g. inocula selection, enrichment, acclimation, operating conditions and cell architecture) that assist the design of MECs. This work intends to be a helpful guide for the interested readers about the strategies employed to successfully establish microbial electrochemical cells for sustainable biohydrogen production

Evolution of dike opening during the March 2011 Kamoamoa fissure eruption, Kīlauea Volcano, Hawai\u27i

The 5–9 March 2011 Kamoamoa fissure eruption along the east rift zone of Kīlauea Volcano, Hawai`i, followed months of pronounced inflation at Kīlauea summit. We examine dike opening during and after the eruption using a comprehensive interferometric synthetic aperture radar (InSAR) data set in combination with continuous GPS data. We solve for distributed dike displacements using a whole Kīlauea model with dilating rift zones and possibly a deep décollement. Modeled surface dike opening increased from nearly 1.5 m to over 2.8 m from the first day to the end of the eruption, in agreement with field observations of surface fracturing. Surface dike opening ceased following the eruption, but subsurface opening in the dike continued into May 2011. Dike volumes increased from 15, to 16, to 21 million cubic meters (MCM) after the first day, eruption end, and 2 months following, respectively. Dike shape is distinctive, with a main limb plunging from the surface to 2–3 km depth in the up-rift direction toward Kīlauea’s summit, and a lesser projection extending in the down-rift direction toward Pu`u `Ō`ō at 2 km depth. Volume losses beneath Kīlauea summit (1.7 MCM) and Pu`u `Ō`ō (5.6 MCM) crater, relative to dike plus erupted volume (18.3 MCM), yield a dike to source volume ratio of 2.5 that is in the range expected for compressible magma without requiring additional sources. Inflation of Kīlauea’s summit in the months before the March 2011 eruption suggests that the Kamoamoa eruption resulted from overpressure of the volcano’s magmatic system

Performance evaluation of microbial electrochemical systems operated with Nafion and supported ionic liquid membranes

In this work, the performance of dual-chamber microbial fuel cells (MFCs) constructed either with commonly used Nafion® proton exchange membrane or supported ionic liquid membranes (SILMs) was assessed. The behavior of MFCs was followed and analyzed by taking the polarization curves and besides, their efficiency was characterized by measuring the electricity generation using various substrates such as acetate and glucose. By using the SILMs containing either [C6mim][PF6] or [Bmim][NTf2] ionic liquids, the energy production of these MFCs from glucose was comparable to that obtained with the MFC employing polymeric Nafion® and the same substrate. Furthermore, the MFC operated with [Bmim][NTf2]-based SILM demonstrated higher energy yield in case of low acetate loading (80.1 J g−1 CODin m−2 h−1) than the one with the polymeric Nafion® N115 (59 J g−1 CODin m−2 h−1). Significant difference was observed between the two SILM-MFCs, however, the characteristics of the system was similar based on the cell polarization measurements. The results suggest that membrane-engineering applying ionic liquids can be an interesting subject field for bioelectrochemical system research

Vacancy driven surface disorder catalyzes anisotropic evaporation of ZnO (0001) polar surface

The evaporation and crystal growth rates of ZnO are highly anisotropic and are fastest on the Zn-terminated ZnO (0001) polar surface. Herein, we study this behavior by direct atomic-scale observations and simulations of the dynamic processes of the ZnO (0001) polar surface during evaporation. The evaporation of the (0001) polar surface is accelerated dramatically at around 300 °C with the spontaneous formation of a few nanometer-thick quasi-liquid layer. This structurally disordered and chemically Zn-deficient quasi-liquid is derived from the formation and inward diffusion of Zn vacancies that stabilize the (0001) polar surface. The quasi-liquid controls the dissociative evaporation of ZnO with establishing steady state reactions with Zn and O$_{2}$ vapors and the underlying ZnO crystal; while the quasi-liquid catalyzes the disordering of ZnO lattice by injecting Zn vacancies, it facilitates the desorption of O$_{2}$ molecules. This study reveals that the polarity-driven surface disorder is the key structural feature driving the fast anisotropic evaporation and crystal growth of ZnO nanostructures along the [0001] direction

Nonparametric numerical approaches to probability weighting function construct for manifestation and prediction of risk preferences

Probability weighting function (PWF) is the psychological probability of a decision-maker for objective probability, which reflects and predicts the risk preferences of decision-maker in behavioral decisionmaking. The existing approaches to PWF estimation generally include parametric methodologies to PWF construction and nonparametric elicitation of PWF. However, few of them explores the combination of parametric and nonparametric elicitation approaches to approximate PWF. To describe quantitatively risk preferences, the Newton interpolation, as a well-established mathematical approximation approach, is introduced to task-specifically match PWF under the frameworks of prospect theory and cumulative prospect theory with descriptive psychological analyses. The Newton interpolation serves as a nonparametric numerical approach to the estimation of PWF by fitting experimental preference points without imposing any specific parametric form assumptions. The elaborated nonparametric PWF model varies in accordance with the number of the experimental preference points elicitation in terms of its functional form. The introduction of Newton interpolation to PWF estimation into decision-making under risk will benefit to reflect and predict the risk preferences of decision-makers both at the aggregate and individual levels. The Newton interpolation-based nonparametric PWF model exhibits an inverse S-shaped PWF and obeys the fourfold pattern of decision-makers’ risk preferences as suggested by previous empirical analyses. First published online 17 April 202

Enhanced Responsivity of Photodetectors Realized via Impact Ionization

To increase the responsivity is one of the vital issues for a photodetector. By employing ZnO as a representative material of ultraviolet photodetectors and Si as a representative material of visible photodetectors, an impact ionization process, in which additional carriers can be generated in an insulating layer at a relatively large electric field, has been employed to increase the responsivity of a semiconductor photodetector. It is found that the responsivity of the photodetectors can be enhanced by tens of times via this impact ionization process. The results reported in this paper provide a general route to enhance the responsivity of a photodetector, thus may represent a step towards high-performance photodetectors