Measurement of horticulture produce quality.

The aim of this work was to develop amperometric biosensors, for the detection of key analytes that affect horticulture produce quality. Information was gathered relating to the interaction between key analytes, such as amino acids, organic acids and sugars and their effect on produce quality. Trends of these key analytes changed in the produce over time, thus their measurement can indicate ripeness. A taste panel analysis on six varieties of tomatoes was therefore carried out. The key analytes were then measured by conventional means and the data was subjected to Principal Component Analysis (PCA). The results indicate that total organic acids correlate well with perceived sweetness of tomatoes. Individual amperometric biosensors for the measurement of L-malic acid, D- glucose, L-ascorbic acid, L-amino acids, and L-glutamic acid were developed during the course of this study. These individual biosensors were tested with real samples and the results were compared with standard photometric tests. The biosensors generally gave high precision values. The L-malic acid biosensor showed a high correlation against the standard method (accuracy = > 87.3 % when testing real samples). One of the problems encountered when testing real samples was the effect of interferent species. Therefore, quantification of the interferent effect was achieved by testing the sample with and without enzyme immobilised onto the working electrode. By calculating the difference in current, an accurate concentration of the target analyte could be measured. Finally, it was understood through the course of this work that measurement of only single analytes is insufficient in determining the quality of horticulture produce. Therefore a multianalyte biosensor was constructed. D-glucose, L-malic acid, and L- ascorbic acid, were tested simultaneously using this biosensor array. The average accuracy of this method, as compared to detection of single analytes was 90 %

Underwater Acoustic Tomography

Ever since the CAT scanner technique for medical imaging was introduced, the fields of tomography and image reconstruction from slices have been gaining in popularity. Towards the end of the last decade, the application of tomographic method to large scale ocean monitoring was explored. This paper surveys the application of tomographic methods to ocean monitoring and surveiIlance

The Conserved Dcw Gene Cluster of R. sphaeroides Is Preceded by an Uncommonly Extended 5’ Leader Featuring the sRNA UpsM

Cell division and cell wall synthesis mechanisms are similarly conserved among bacteria. Consequently some bacterial species have comparable sets of genes organized in the dcw (division and cell wall) gene cluster. Dcw genes, their regulation and their relative order within the cluster are outstandingly conserved among rod shaped and gram negative bacteria to ensure an efficient coordination of growth and division. A well studied representative is the dcw gene cluster of E. coli. The first promoter of the gene cluster (mraZ1p) gives rise to polycistronic transcripts containing a 38 nt long 5’ UTR followed by the first gene mraZ. Despite reported conservation we present evidence for a much longer 5’ UTR in the gram negative and rod shaped bacterium Rhodobacter sphaeroides and in the family of Rhodobacteraceae. This extended 268 nt long 5’ UTR comprises a Rho independent terminator, which in case of termination gives rise to a non-coding RNA (UpsM). This sRNA is conditionally cleaved by RNase E under stress conditions in an Hfq- and very likely target mRNA-dependent manner, implying its function in trans. These results raise the question for the regulatory function of this extended 5’ UTR. It might represent the rarely described case of a trans acting sRNA derived from a riboswitch with exclusive presence in the family of Rhodobacteraceae

Transcriptomic footprints disclose specificity of reactive oxygen species signaling in Arabidopsis

Reactive oxygen species ( ROS) are key players in the regulation of plant development, stress responses, and programmed cell death. Previous studies indicated that depending on the type of ROS ( hydrogen peroxide, superoxide, or singlet oxygen) or its subcellular production site ( plastidic, cytosolic, peroxisomal, or apoplastic), a different physiological, biochemical, and molecular response is provoked. We used transcriptome data generated from ROS-related microarray experiments to assess the specificity of ROS-driven transcript expression. Data sets obtained by exogenous application of oxidative stress-causing agents ( methyl viologen, Alternaria alternata toxin, 3-aminotriazole, and ozone) and from a mutant ( fluorescent) and transgenic plants, in which the activity of an individual antioxidant enzyme was perturbed ( catalase, cytosolic ascorbate peroxidase, and copper/zinc superoxide dismutase), were compared. In total, the abundance of nearly 26,000 transcripts of Arabidopsis ( Arabidopsis thaliana) was monitored in response to different ROS. Overall, 8,056, 5,312, and 3,925 transcripts showed at least a 3-, 4-, or 5- fold change in expression, respectively. In addition to marker transcripts that were specifically regulated by hydrogen peroxide, superoxide, or singlet oxygen, several transcripts were identified as general oxidative stress response markers because their steady-state levels were at least 5- fold elevated in most experiments. We also assessed the expression characteristics of all annotated transcription factors and inferred new candidate regulatory transcripts that could be responsible for orchestrating the specific transcriptomic signatures triggered by different ROS. Our analysis provides a framework that will assist future efforts to address the impact of ROS signals within environmental stress conditions and elucidate the molecular mechanisms of the oxidative stress response in plants

Sound source localization through shape reconfiguration in a snake robot

This paper describes a snake robot system that uses sound source localization. We show in this paper as to how we can localize a sound source in 3D and solve the classic forward backward problem in sound source localization using minimum number of audio sensors by using the multiple degrees of freedom of the snake robot. We describe the hardware and software architecture of the robot and show the results of several sound tracking experiments we did with our snake robot. We also present biologically inspired sound tracking behavior in different postures of a biological snake robot as "Digital Snake Charming"

Comparative study of extracellular recording methods for analysis of afferent sensory information: Empirical modeling, data analysis and interpretation

Background: Physiological studies of sensorial systems often require the acquisition and processing of data extracted from their multiple components to evaluate how the neural information changes in relation to the environment changes. In this work, a comparative study about methodological aspects of two electrophysiological approaches is described. New method: Extracellular recordings from deep vibrissal nerves were obtained by using a customized microelectrode Utah array during passive mechanical stimulation of rat´s whiskers. These recordings were compared with those obtained with bipolar electrodes. We also propose here a simplified empirical model of the electrophysiological activity obtained from a bundle of myelinated nerve fibers. Results: The peripheral activity of the vibrissal system was characterized through the temporal and spectral features obtained with both recording methods. The empirical model not only allows the correlation between anatomical structures and functional features, but also allows to predict changes in the CAPs morphology when the arrangement and the geometry of the electrodes changes. Comparison with existing method(s): This study compares two extracellular recording methods based on analysis techniques, empirical modeling and data processing of vibrissal sensory information. Conclusions: This comparative study reveals a close relationship between the electrophysiological techniques and the processing methods necessary to extract sensory information. This relationship is the result of maximizing the extraction of information from recordings of sensory activity.Fil: Farfan, Fernando Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Bioingeniería. Laboratorio de Medios e Interfases; ArgentinaFil: Soto Sanchez, Cristina. Universidad de Miguel Hernández; España. Consorcio Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina; EspañaFil: Pizá, Alvaro Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Bioingeniería. Laboratorio de Medios e Interfases; ArgentinaFil: Albarracin, Ana Lia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Bioingeniería. Laboratorio de Medios e Interfases; ArgentinaFil: Soletta, Jorge Humberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Bioingeniería. Laboratorio de Medios e Interfases; ArgentinaFil: Lucianna, Facundo Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Bioingeniería. Laboratorio de Medios e Interfases; ArgentinaFil: Fernandez, Esteve. Universidad de Miguel Hernández; España. Consorcio Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina; Españ

Transcriptomic changes in the airway due to diesel engine exhaust exposure

INTRODUCTION: Recent epidemiological studies have shown that Diesel Engine Exhaust (DEE) exposure is associated with lung cancer. Well recognized exposures, such as smoking, have long been known to cause lung cancer, and the mechanisms by which the disease occurs have been closely investigated. However, there is very little information regarding the mechanisms by which chronic DEE exposure leads to a disease outcome. It has also been shown that transcriptomic changes in the deeper portions of the airway may be detectable in the more proximal parts. The goal of this study was to assess transcriptomic alterations in the nasal epithelium of DEE exposed factory workers to better understand the physiologic effects of DEE and how chronic exposure may lead to disease. METHODS: Nasal epithelium brushings were obtained from 41 subjects who work in a factory with DEE exposure, and 38 comparable control subjects who work in factories without DEE exposure. The median Elemental Carbon (EC) levels of exposed individuals was 60.7g/m3, with a range of 17.2-105.4 g/m3, while the median of EC levels of unexposed controls was 10.87g/m3, with a range of 9.89-12.55g/m3. RNA was isolated from nasal epithelial cells, and profiled for gene expression using Affymetrix Human Gene 1.0ST microarray chips. Linear modeling was used to detect differential expression between DEE exposure and controls. Pathway enrichment in differentially expressed genes was assessed using EnrichR. GSEA provided comparisons between the genes known to be differentially expressed due to smoking, and the genes that were found in our data to be differentially expressed due to smoking or DEE. A linear modeling approach was further used to investigate the effects of the interaction between smoking status and DEE exposure, and boxplot analysis was used to explore the interaction effect. RESULTS: We found 225 genes whose expression is associated with DEE exposure at FDR q < 0.25, after adjusting for smoking status. Within this set of genes, we observed increased expression of genes involved in the oxidative stress response, cell cycle, and protein modification, as well as genes associated with the AhR pathway and the Nrf2-mediated xenobiotic metabolism response. Additionally, decreased expression of genes involved in transmembrane transport, such as CFTR and the solute carrier family genes was also found. Furthermore, we discovered 8 genes at FDR q < 0.25 that have altered expression due to the interaction of DEE and smoking status, suggesting a synergistic relationship between the effects of these exposures on some aspects of the physiological response. For these genes, the effects of DEE were generally more dramatic in never smokers. CONCLUSIONS: The transcriptomic alterations we identified may help provide insight into the underlying mechanisms of DEE carcinogenicity. The relationship between cigarette smoke exposure and DEE exposure may provide more information about how chronic DEE exposure leads to lung cancer and other respiratory diseases

Recent developments in hole cleaning technology in deviated well bores for geothermal and petroleum

This paper is looking on recent developments in hole cleaning technologies and how recent advancements can be used to aid efficient hole cleaning in deviated wells. Successful hole cleaning relies upon integrating optimum drilling fluid properties with the best drilling practices. The ability of the drilling fluid to transport the drilling cuttings to the are determined by several parameters (cutting density, mud weight, hole-size, hole-angle, rheology of fluid, cutting size, rate of penetration, drill pipe eccentricity, drill pipe rotation speed, phase of fluid, cutting transport ratio and cutting bed properties). Efficient hole cleaning of deviated wells is important and difficult to perform efficiently, deviated wells normally uses drilling fluid with lower viscosity and gel building properties than in vertical section. Deviated wells are an important tool to either boost the return from existing fields or gaining access to new and formerly inaccessible formations. The increasing need for oil and gas have kept increasing with ever increasing energy output in the world, despite the world trying to swap to more renewable resources. Petroleum products such as coal, gas and oil still stand for over 80% of the energy production in the world. Increasing energy demands from the world exceeds the development within renewable technologies and gaining access to new formation and extracting most of the oil and gas in current formation will be paramount in giving people access to energy required to keep the world running. Percentage of world’s energy coming from renewable resources has increased and will hopefully keep increasing, but total energy demand especially from developing countries with increasing population and higher standard of living requires higher amount of energy than the countries are currently consuming with renewable being too expensive, inefficient, or lacking the required infrastructure for implementation. The paper is a compilation of recent developments and would hopefully give the reader insight in the processes most important efficient hole cleaning for deviated wells. The topic of efficient hole cleaning is complex, and a lot of different parameters will be introduced to understand the role of new developments. Basic understanding of these parameters and their interplay with each other is required to understand to keep the innovation with respect to efficient hole cleaning and automating more of the process involved in hole cleaning while drilling in deviated wells. The paper also uses the information from collected studies to write to a data code based on recent developments to aid in controlling the right rate of penetration (ROP) during drilling. No independent research was those in this paper and is based on the work of research and literature of others

Molecular and computational approach to the link between nutrition and cancer

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Química Física Aplicada. Fecha de lectura: 22-11-201