Measurement of the temperature-dependent speed of sound and change in Gruneisen parameter of tissue-mimicking materials

Knowledge of the temperature dependence of the material properties of tissue-mimicking materials is useful or essential for many applications. This includes photoacoustic thermometry where the temperature dependence of the Grüneisen parameter of tissues leads to changes in the recorded photoacoustic signal amplitude with temperature. Here, a setup is described that can measure the temperature dependence of the speed of sound and photoacoustic conversion efficiency (μ a Γ) of tissue-mimicking materials. Agar-based phantoms, copolymer-in-oil, gel wax, PVCP, silicone and water were characterised in the newly developed setup for temperatures between 22°C and 50°C. This information provides a valuable resource for material characterisation and future development of tissue-mimicking materials

Analisis Pola Konsumsi Keluarga Buruh Tani Singkong dan Buruh Penyadap Karet

The aims of the study were to analyze and describe the consumption pattern of the families belonging to cassava and rubber laborers in in Sawojajar village. This research used comparative descriptive method. The data analysis employed was descriptive statistic. The findings revealed that (1) The total income of both workers is under Lampung UMP, the families of cassava laborers and families of rubber laborers; (2) Food and non-food consumption of the rubber laborers families were more fulfilled than food consumption of the cassava laborers families; (3) The welfare rate of rubber laborers workers is higher than that of cassava laborers because the percentage of food consumption is smaller than the total expenditure.Penelitian ini bertujuan menganalisis dan menggambarkan pola konsumsi keluarga buruh tani singkong dan buruh penyadap karet di Desa Sawojajar. Metode penelitian yaitu metode deskriptif komparatif. Hasil penelitian menunjukkan: (1) Pendapatan total kedua buruh berada dibawah UMP Lampung, baik keluarga buruh tani singkong maupun keluarga buruh penyadap karet; (2) Konsumsi makanan dan nonmakanan keluarga buruh penyadap karet lebih terpenuhi dibandingkan keluarga buruh tani singkong; (3) Tingkat kesejahteraan keluarga buruh penyadap karet lebih tinggi dibandingkan buruh tani singkong dikarenakan persentase konsumsi makanan lebih kecil daripada total pengeluaran

Dynamical Monodromy

Integrable Hamiltonian systems are said to display nontrivial monodromy if fundamental action-angle loops defined on phase-space tori change their topological structure when the system is carried around a circuit. In an earlier paper it was shown that this topological change can occur as a result of time evolution under certain rather abstract flows in phase space. In the present paper, we show that the same topological change can occur as a result of application of ordinary forces. We also show how this dynamical phenomenon could be observed experimentally in classical or in quantum systems

Ballistic Atom Pumps

We examine a classically chaotic system consisting of two reservoirs of particles connected by a channel containing oscillating potential-energy barriers. We investigate whether such a system can preferentially pump particles from one reservoir to the other, a process often called “quantum pumping.” We show how to make a “particle diode” which under specified conditions permits net particle pumping in only one direction. Then we examine systems having symmetric barriers. We find that if all initial particle energies are considered, a system with symmetric barriers cannot preferentially pump particles. However, if only finite initial energy bands are considered, the system can create net particle transport in either direction. We study the system classically, semiclassically, and quantum mechanically, and find that the quantum description cannot be fully understood without the insight gained from classical and semiclassical analysis

Comparison of Niskin vs. in situ approaches for analysis of gene expression in deep Mediterranean Sea water samples

Author Posting. © The Author(s), 2014. This is the author's version of the work. It is posted here by permission of Elsevier for personal use, not for redistribution. The definitive version was published in Deep Sea Research Part II: Topical Studies in Oceanography 129 (2016): 213-222, doi:10.1016/j.dsr2.2014.10.020.Obtaining an accurate picture of microbial processes occurring in situ is essential for our understanding of marine biogeochemical cycles of global importance. Water samples are typically collected at depth and returned to the sea surface for processing and downstream experiments. Metatranscriptome analysis is one powerful approach for investigating metabolic activities of microorganisms in their habitat and which can be informative for determining responses of microbiota to disturbances such as the Deepwater Horizon oil spill. For studies of microbial processes occurring in the deep sea, however, sample handling, pressure, and other changes during sample recovery can subject microorganisms to physiological changes that alter the expression profile of labile messenger RNA. Here we report a comparison of gene expression profiles for whole microbial communities in a bathypelagic water column sample collected in the Eastern Mediterranean Sea using Niskin bottle sample collection and a new water column sampler for studies of marine microbial ecology, the Microbial Sampler – In Situ Incubation Device (MS-SID). For some taxa, gene expression profiles from samples collected and preserved 33 in situ were significantly different from potentially more stressful Niskin sampling and 34 preservation on deck. Some categories of transcribed genes also appear to be affected by sample 35 handling more than others. This suggests that for future studies of marine microbial ecology, 36 particularly targeting deep sea samples, an in situ sample collection and preservation approach 37 should be considered.This research was funded by NSF OCE-1061774 to VE and CT, NSF DBI-0424599 to CT and NSF OCE-0849578 to VE and colleague J. Bernhard. Cruise participation was partially supported by Deutsche Forschungsgemeinschaft (DFG) grant STO414/10-1 to T. Stoeck

Scattering By an Oscillating Barrier: Quantum, Classical, and Semiclassical Comparison

We present a detailed study of scattering by an amplitude-modulated potential barrier using three distinct physical frameworks: quantum, classical, and semiclassical. Classical physics gives bounds on the energy and momentum of the scattered particle, while also providing the foundation for semiclassical theory. We use the semiclassical approach to selectively add quantum-mechanical effects such as interference and diffraction. We find good agreement between the quantum and semiclassical momentum distributions. Our methods and results can be used to understand quantum and classical aspects of transport mechanisms involving time-varying potentials, such as quantum pumping

Identification of Cytokinin-Responsive Genes Using Microarray Meta-Analysis and RNA-Seq in Arabidopsis

Cytokinins are N6-substituted adenine derivatives that play diverse roles in plant growth and development. We sought to define a robust set of genes regulated by cytokinin as well as to query the response of genes not represented on microarrays. To this end, we performed a meta-analysis of microarray data from a variety of cytokinin-treated samples and used RNA-seq to examine cytokinin-regulated gene expression in Arabidopsis (Arabidopsis thaliana). Microarray meta-analysis using 13 microarray experiments combined with empirically defined filtering criteria identified a set of 226 genes differentially regulated by cytokinin, a subset of which has previously been validated by other methods. RNA-seq validated about 73% of the up-regulated genes identified by this meta-analysis. In silico promoter analysis indicated an overrepresentation of type-B Arabidopsis response regulator binding elements, consistent with the role of type-B Arabidopsis response regulators as primary mediators of cytokinin-responsive gene expression. RNA-seq analysis identified 73 cytokinin-regulated genes that were not represented on the ATH1 microarray. Representative genes were verified using quantitative reverse transcription-polymerase chain reaction and NanoString analysis. Analysis of the genes identified reveals a substantial effect of cytokinin on genes encoding proteins involved in secondary metabolism, particularly those acting in flavonoid and phenylpropanoid biosynthesis, as well as in the regulation of redox state of the cell, particularly a set of glutaredoxin genes. Novel splicing events were found in members of some gene families that are known to play a role in cytokinin signaling or metabolism. The genes identified in this analysis represent a robust set of cytokinin-responsive genes that are useful in the analysis of cytokinin function in plants