Multi-silicon ridge nanofabrication by repeated edge lithography

We present a multi-Si nanoridge fabrication scheme and its application in nanoimprint\ud lithography (NIL). Triple Si nanoridges approximately 120 nm high and 40 nm wide separated\ud by 40 nm spacing are fabricated and successfully applied as a stamp in nanoimprint lithography.\ud The fabrication scheme, using a full-wet etching procedure in combination with repeated edge\ud lithography, consists of hot H3PO4 acid SiNx retraction etching, 20% KOH Si etching, 50% HF\ud SiNx retraction etching and LOCal Oxidation of Silicon (LOCOS). Si nanoridges with smooth\ud vertical sidewalls are fabricated by using Si 110 substrates and KOH etching. The presented\ud technology utilizes a conventional photolithography technique, and the fabrication of multi-Si\ud nanoridges on a full wafer scale has been demonstrated

Formation of delta ferrite in 9 wt.% Cr steel investigated by in-situ X-ray diffraction using synchrotron radiation

In-situ X-ray diffraction (XRD) measurements using high energy synchrotron radiation were performed to monitor in real time the formation of delta ferrite in a martensitic 9 wt pct chromium steel under simulated weld thermal cycles. Volume fractions of martensite, austenite, and delta ferrite were measured as a function of temperature at a 10 K/s heating rate to 1573 K (1300 °C) and subsequent cooling. At the peak temperature, the delta ferrite concentration rose to 19 pct, of which 17 pct transformed back to austenite on subsequent cooling.Max Kade Foundation, Inc.Austrian Academy of SciencesUnited States. Dept. of Energy (Division of Materials Sciences and Engineering, Office of Science, and Office of Basic Energy Sciences

The Analysis of SKP1 Gene Expression in Physiological Male Sterility Induced by Chemical Hybridizing Agent SQ-1 in Wheat (Triticum aestivum L.)

Physiological male sterility induced by the chemical hybridizing agent (CHA) overcomes problems of maintenance of sterile lines and restorers. However, the mechanism of sterility is unclear. The process of tapetum of CHA-treated ‘Xi’nong 2611’ at uninucleate, binucleate and trinucleate were compared with control to determine if tapetum varying differently during developmental stages. Tapetal degradation in CHA-treated ‘Xi’nong 2611’ began at late uninucleate stage, somewhat earlier than control plants. Cytological observations indicated that the gradual degradation of the tapetum in CHA-treated ‘Xi’nong 2611’ was initiated and terminated earlier than in the control. These findings implied that CHA-induced male sterility was related to abnormally early tapetal degradation. In order to indicate the role of the SKP1 gene in fertility/sterility in wheat, its expression was assessed in anthers at uninucleate, binucleate and trinucleate stages. SKP1 expression was reduced in the later developmental stages, and there was an obvious decrease from the uninucleate to trinucleate stages. Higher expression of the SKP1 gene occurred in ‘Xi’nong 2611’ compared to CHA-treated ‘Xi’nong 2611’. This implied that SKP1 gene expression was inhibited during the fertility transformation process and was related to transformation from fertility to sterility. Moreover, the results from this study suggest that SKP1 plays an essential role of conducting fertility in physiological male sterility

Syncytialization and prolonged exposure to palmitate impacts bewo respiration

Placental villous trophoblast mitochondrial respiratory function is critical for a successful pregnancy and environmental influences such as maternal obesity have been associated with respiratory impairment at term. More recently, a gestational high fat diet independent of maternal body composition, has been highlighted as a potential independent regulator of placental mitochondrial metabolism. The current study aimed to characterize the direct impact of a prolonged and isolated exposure to the dietary fatty acids Palmitate (PA) and Oleate (OA) upon placental cell mitochondrial respiratory function. BeWo cytotrophoblast (CT) and syncytiotrophoblast (SCT) cells were treated for 72 h with 100 μM PA, OA or PA+OA (P/O). Live-cell metabolic function was analyzed via the Seahorse XF Mito and Glycolysis Stress tests. Immunoblots and spectrophotometric activity assays were utilized to examine the protein expression and function of electron transport chain (ETC) complexes and key mitochondrial regulatory enzymes. Syncytialization of BeWo cells resulted reduced respiratory activity in conjunction with altered complex I and II activity and decreased pyruvate dehydrogenase (PDH) protein expression and activity. PA and P/O treatments were associated with increased basal and maximal respiratory activities in BeWo CT cells without alterations in protein expression or activity of individual ETC complexes and mitochondrial substrate regulators. The metabolic suppression in BeWo SCTs was consistent with that previously observed in primary human trophoblast cell cultures, while the observed increases in respiratory activity in PA-treated BeWo CTs may be indicative of an early timepoint of specific dietary saturated fat-mediated placental cell mitochondrial dysfunction

Hidden symmetries for thermodynamics and emergence of relativity

Erik Verlinde recently proposed an idea about the thermodynamic origin of gravity. Though this is a beautiful idea which may resolve many long standing problems in the theories of gravity, it also raises many other problems. In this article I will comment on some of the problems of Verlinde's proposal with special emphasis on the thermodynamical origin of the principle of relativity. It is found that there is a large group of hidden symmetries of thermodynamics which contains the Poincare group of the spacetime for which space is emergent. This explains the thermodynamic origin of the principle of relativity.Comment: V1: 4 pages, comments/criticisms welcomed; V2: references added; V3: typos and minor corrections? V4? substantial changes in Section 3 and other parts mad

A User-centric Framework for Accessing Biological Sources and Tools

Biologists face two problems in interpreting their experiments: the integration of their data with information from multiple heterogeneous sources and data analysis with bioinformatics tools. It is difficult for scientists to choose between the numerous sources and tools without assistance. Following a thorough analysis of scientists’ needs during the querying process, we found that biologists express preferences concerning the sources to be queried and the tools to be used. Interviews also showed that the querying process itself – the strategy followed – differs between scientists. In response to these findings, we have introduced a user-centric framework allowing to specify various querying processes. Then we have developed the BioGuide system which helps the scientists to choose suitable sources and tools, find complementary information in sources, and deal with divergent data. It is generic in that it can be adapted by each user to provide answers respecting his/her preferences, and obtained following his/her strategies

Marketing to Liminal Consumers:Migrant Workers as an Emerging Segment in Transitional Economies

Though most acculturation research investigates movement across national boundaries, many other types of boundaries may exist (e.g. rural to urban migration). Rural migrant workers focus on their adaptive and exploratory consumption practices to assemble a liquid identity in China. In essence, this research examines the nature of the transitions that the vast group of Chinese (over 280 million) endures as migrant workers seek to assemble new identities through consumption activities in a liminal space. We find that family relations and government policy hinder migrants’ adjustments to urban life. Thus, we contribute to macromarketing by enriching the theories of liquid identity, boundary work, and acculturation

Patterning the neuronal cells via inkjet printing of self-assembled peptides on silk scaffolds

The patterning of neuronal cells and guiding neurite growth are important for neuron tissue engineering and cell-based biosensors. In this paper, inkjet printing has been employed to pattern self-assembled I3QGK peptide nanofibers on silk substrates for guiding the growth of neuron-like PC12 cells. Atomic force microscopy (AFM) confirmed the dynamic self-assembly of I3QGK into nanofiber structures. The printed self-assembled peptide strongly adheres to regenerated silk fibroin (RSF) substrates through charge-charge interactions. It was observed that in the absence of I3QGK, PC12 cells exhibited poor attachment to RSF films, while for RSF surfaces coated or printed with peptide nanofibers, cellular attachment was significantly improved in terms of both cell density and morphology. AFM results revealed that peptide nanofibers can promote the generation of axons and terminal buttons of PC12 cells, indicating that I3QGK nanofibers not only promote cellular attachment but also facilitate differentiation into neuronal phenotypes. Inkjet printing allows complex patterning of peptide nanofibers onto RSF substrates, which enabled us to engineer cell alignment and provide an opportunity to direct axonal development in vitro. The live/dead assay showed that printed I3QGK patterns exhibit no cytotoxicity to PC12 cells demonstrating potential for future nerve tissue engineering applications