Low cost light-sheet microscopy for whole brain imaging

Science.gov (United States)

Kumar, Manish; Nasenbeny, Jordan; Kozorovitskiy, Yevgenia

2018-02-01

Light-sheet microscopy has evolved as an indispensable tool in imaging biological samples. It can image 3D samples at fast speed, with high-resolution optical sectioning, and with reduced photobleaching effects. These properties make light-sheet microscopy ideal for imaging fluorophores in a variety of biological samples and organisms, e.g. zebrafish, drosophila, cleared mouse brains, etc. While most commercial turnkey light-sheet systems are expensive, the existing lower cost implementations, e.g. OpenSPIM, are focused on achieving high-resolution imaging of small samples or organisms like zebrafish. In this work, we substantially reduce the cost of light-sheet microscope system while targeting to image much larger samples, i.e. cleared mouse brains, at single-cell resolution. The expensive components of a lightsheet system - excitation laser, water-immersion objectives, and translation stage - are replaced with an incoherent laser diode, dry objectives, and a custom-built Arduino-controlled translation stage. A low-cost CUBIC protocol is used to clear fixed mouse brain samples. The open-source platforms of μManager and Fiji support image acquisition, processing, and visualization. Our system can easily be extended to multi-color light-sheet microscopy.

Low-cost and versatile thermal test chip for power assemblies assessment and thermometric calibration purposes

International Nuclear Information System (INIS)

Jorda, X.; Perpina, X.; Vellvehi, M.; Madrid, F.; Flores, D.; Hidalgo, S.; Millan, J.

2011-01-01

Chips specifically designed for thermal tests such as the assessment of packages, are of main interest in Microelectronics. Nevertheless, these test dies are required in relatively low quantities and their price is a limiting factor. This work describes a low-cost thermal test chip, specifically developed for the needs of power electronics. It is based on a poly-silicon heating resistor and a decoupled Pt temperature sensing resistor on the top, allowing to dissipate more than 60 W (170 W/cm 2 ) and reaching temperatures up to 200 o C. Its simple structure allows an easy simulation and modeling. These features have been taken in profit for packaging materials assessment, calibration of temperature measurement apparatus and methods, and validation of thermal models and simulations. - Highlights: → We describe a low-cost thermal test chip developed for power electronics applications. → It integrates a poly-silicon heating resistor and a Pt temperature sensing resistor on the top. → It can dissipate up to 200 W/cm 2 and work up to 200 o C. → It has been used for thermal resistance and conductivity measurement of substrates. → It allowed also the calibration of advanced thermometric equipments.

Metabolite Profiling of Four Major Flavonoids of Herba Epimdii in Zebrafish

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Xiaobin Jia

2012-01-01

Full Text Available The zebrafish model organism was applied first in a metabolic study of icariin, baohuoside I, epimedin A and epimedin C, which are flavonoids in Herba Epimedii. Metabolites of these compounds in zebrafish after exposure for 24 h were identified by HPLC-ESI-MS, whereby the separation was performed with a Zorbax C-18 column using a gradient elution of 0.05% formic acid acetonitrile-0.05% formic acid water. The quasi-molecular ions of compounds were detected in simultaneous negative and positive ionization modes. Metabolic products of icariin and epimedin C via cleavage of glucose residue instead of rhamnose residues were found, which coincided with the results using regular metabolic analysis methods. In addition, the zebrafish model was used to predict the metabolism of the trace component epimedin A, whose metabolic mechanisms haven’t been clearly elucidated with the current metabolism model. The metabolic pathway of epimedin A in zebrafish was similar to those of its homologue icariin and epimedin C. Our study demonstrated that the zebrafish model can successfully imitate the current models in elucidating metabolic pathways of model flavonoids, which has advantages of lower cost, far less amount of compound needed, easy set up and high performance. This novel model can also be applied in quickly predicting the metabolism of Chinese herb components, especially trace compounds.

Cultural Heritage Recording Utilising Low-Cost Closerange Photogrammetry

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Melanie Kirchhöfer

2011-12-01

Full Text Available Cultural heritage is under a constant threat of damage or even destruction and comprehensive and accurate recording is necessary to attenuate the risk of losing heritage or serve as basis for reconstruction. Cost effective and easy to use methods are required to record cultural heritage, particularly during a world recession, and close-range photogrammetry has proven potential in this area. Off-the-shelf digital cameras can be used to rapidly acquire data at low cost, allowing non-experts to become involved. Exterior orientation of the camera during exposure ideally needs to be established for every image, traditionally requiring known coordinated target points. Establishing these points is time consuming and costly and using targets can be often undesirable on sensitive sites. MEMS-based sensors can assist in overcoming this problem by providing small-size and low-cost means to directly determine exterior orientation for close-range photogrammetry. This paper describes development of an image-based recording system, comprising an off-the-shelf digital SLR camera, a MEMS-based 3D orientation sensor and a GPS antenna. All system components were assembled in a compact and rigid frame that allows calibration of rotational and positional offsets between the components. The project involves collaboration between English Heritage and Loughborough University and the intention is to assess the system’s achievable accuracy and practicability in a heritage recording environment. Tests were conducted at Loughborough University and a case study at St. Catherine’s Oratory on the Isle of Wight, UK. These demonstrate that the data recorded by the system can indeed meet the accuracy requirements for heritage recording at medium accuracy (1-4cm, with either a single or even no control points. As the recording system has been configured with a focus on low-cost and easy-to-use components, it is believed to be suitable for heritage recording by non

Preliminary design of a low-cost greenhouse for salt production in Indonesia

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Jaziri, A. A.; Guntur; Setiawan, W.; Prihanto, A. A.; Kurniawan, A.

2018-04-01

Salt is an assential material of industry, not only in food industry point of view but also in various industries such as chemical, oil drilling, and animal feed industries, even less than half of salt needs used to household consumption. It is crucial to ensure salt production in Indonesia reaches the national target (3.7 million tons) due to relatively low technology and production level. Thus salt production technology is developed to facilitate farmers consisted of geomembrane and filtering-threaded technology. However, the use of those technologies in producing salt was proved less effective due to unpredictable weather conditions. Therefore, greenhouse technology is proposed to be used for salt production for several good reasons. This paper describes the preliminary design of a low-cost greenhouse designed as a pyramid model that uses bamboo, mono-layer and high density polyethylene plastics. The results confirmed that the yield of salt produced by greenhouse significantly incresed compared with prior technology and the NaCl content increased as well. The cost of greenhouse was IDR 5,688,000 and easy to assembly.

Development of Alginate Microspheres Containing Chuanxiong for Oral Administration to Adult Zebrafish

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Li-Jen Lin

2016-01-01

Full Text Available Oral administration of Traditional Chinese Medicine (TCM by patients is the common way to treat health problems. Zebrafish emerges as an excellent animal model for the pharmacology investigation. However, the oral delivery system of TCM in zebrafish has not been established so far. This issue was addressed by development of alginate microparticles for oral delivery of chuanxiong, a TCM that displays antifibrotic and antiproliferative effects on hepatocytes. The delivery microparticles were prepared from gelification of alginate containing various levels of chuanxiong. The chuanxiong-encapsulated alginate microparticles were characterized for their solubility, structure, encapsulation efficiency, the cargo release profile, and digestion in gastrointestinal tract of zebrafish. Encapsulation of chuanxiong resulted in more compact structure and the smaller size of microparticles. The release rate of chuanxiong increased for alginate microparticles carrying more chuanxiong in simulated intestinal fluid. This remarkable feature ensures the controlled release of encapsulated cargos in the gastrointestinal tract of zebrafish. Moreover, chuanxiong-loaded alginate microparticles were moved to the end of gastrointestinal tract after oral administration for 6 hr and excreted from the body after 16 hr. Therefore, our developed method for oral administration of TCM in zebrafish is useful for easy and rapid evaluation of the drug effect on disease.

Towards a comprehensive catalog of zebrafish behavior 1.0 and beyond.

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Kalueff, Allan V; Gebhardt, Michael; Stewart, Adam Michael; Cachat, Jonathan M; Brimmer, Mallorie; Chawla, Jonathan S; Craddock, Cassandra; Kyzar, Evan J; Roth, Andrew; Landsman, Samuel; Gaikwad, Siddharth; Robinson, Kyle; Baatrup, Erik; Tierney, Keith; Shamchuk, Angela; Norton, William; Miller, Noam; Nicolson, Teresa; Braubach, Oliver; Gilman, Charles P; Pittman, Julian; Rosemberg, Denis B; Gerlai, Robert; Echevarria, David; Lamb, Elisabeth; Neuhauss, Stephan C F; Weng, Wei; Bally-Cuif, Laure; Schneider, Henning

2013-03-01

Zebrafish (Danio rerio) are rapidly gaining popularity in translational neuroscience and behavioral research. Physiological similarity to mammals, ease of genetic manipulations, sensitivity to pharmacological and genetic factors, robust behavior, low cost, and potential for high-throughput screening contribute to the growing utility of zebrafish models in this field. Understanding zebrafish behavioral phenotypes provides important insights into neural pathways, physiological biomarkers, and genetic underpinnings of normal and pathological brain function. Novel zebrafish paradigms continue to appear with an encouraging pace, thus necessitating a consistent terminology and improved understanding of the behavioral repertoire. What can zebrafish 'do', and how does their altered brain function translate into behavioral actions? To help address these questions, we have developed a detailed catalog of zebrafish behaviors (Zebrafish Behavior Catalog, ZBC) that covers both larval and adult models. Representing a beginning of creating a more comprehensive ethogram of zebrafish behavior, this effort will improve interpretation of published findings, foster cross-species behavioral modeling, and encourage new groups to apply zebrafish neurobehavioral paradigms in their research. In addition, this glossary creates a framework for developing a zebrafish neurobehavioral ontology, ultimately to become part of a unified animal neurobehavioral ontology, which collectively will contribute to better integration of biological data within and across species.

TERATOLOGIC EFFECTS OF BISPHENOL A ON ZEBRAFISH (Danio rerio

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Cansu Akbulut

2013-01-01

Full Text Available Zebrafish (Danio rerio has easy reproductive capacity and transparent embryos and therefore generally preffered for scientific studies as a vertebrate model. Because of bisphenol A is produced too much and used for making plastics, many organisms including human are exposed to this substance. Bisphenol A has estrogenic activity and thus it effects fertility. So, in our study, effects of low doses of bisphenol A (4mg/L and 8 mg/L on embryo and larva development was investigated.

The €100 lab: A 3D-printable open-source platform for fluorescence microscopy, optogenetics, and accurate temperature control during behaviour of zebrafish, Drosophila, and Caenorhabditis elegans.

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Andre Maia Chagas

2017-07-01

Full Text Available Small, genetically tractable species such as larval zebrafish, Drosophila, or Caenorhabditis elegans have become key model organisms in modern neuroscience. In addition to their low maintenance costs and easy sharing of strains across labs, one key appeal is the possibility to monitor single or groups of animals in a behavioural arena while controlling the activity of select neurons using optogenetic or thermogenetic tools. However, the purchase of a commercial solution for these types of experiments, including an appropriate camera system as well as a controlled behavioural arena, can be costly. Here, we present a low-cost and modular open-source alternative called 'FlyPi'. Our design is based on a 3D-printed mainframe, a Raspberry Pi computer, and high-definition camera system as well as Arduino-based optical and thermal control circuits. Depending on the configuration, FlyPi can be assembled for well under €100 and features optional modules for light-emitting diode (LED-based fluorescence microscopy and optogenetic stimulation as well as a Peltier-based temperature stimulator for thermogenetics. The complete version with all modules costs approximately €200 or substantially less if the user is prepared to 'shop around'. All functions of FlyPi can be controlled through a custom-written graphical user interface. To demonstrate FlyPi's capabilities, we present its use in a series of state-of-the-art neurogenetics experiments. In addition, we demonstrate FlyPi's utility as a medical diagnostic tool as well as a teaching aid at Neurogenetics courses held at several African universities. Taken together, the low cost and modular nature as well as fully open design of FlyPi make it a highly versatile tool in a range of applications, including the classroom, diagnostic centres, and research labs.

Automated packaging platform for low-cost high-performance optical components manufacturing

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Ku, Robert T.

2004-05-01

Delivering high performance integrated optical components at low cost is critical to the continuing recovery and growth of the optical communications industry. In today's market, network equipment vendors need to provide their customers with new solutions that reduce operating expenses and enable new revenue generating IP services. They must depend on the availability of highly integrated optical modules exhibiting high performance, small package size, low power consumption, and most importantly, low cost. The cost of typical optical system hardware is dominated by linecards that are in turn cost-dominated by transmitters and receivers or transceivers and transponders. Cost effective packaging of optical components in these small size modules is becoming the biggest challenge to be addressed. For many traditional component suppliers in our industry, the combination of small size, high performance, and low cost appears to be in conflict and not feasible with conventional product design concepts and labor intensive manual assembly and test. With the advent of photonic integration, there are a variety of materials, optics, substrates, active/passive devices, and mechanical/RF piece parts to manage in manufacturing to achieve high performance at low cost. The use of automation has been demonstrated to surpass manual operation in cost (even with very low labor cost) as well as product uniformity and quality. In this paper, we will discuss the value of using an automated packaging platform.for the assembly and test of high performance active components, such as 2.5Gb/s and 10 Gb/s sources and receivers. Low cost, high performance manufacturing can best be achieved by leveraging a flexible packaging platform to address a multitude of laser and detector devices, integration of electronics and handle various package bodies and fiber configurations. This paper describes the operation and results of working robotic assemblers in the manufacture of a Laser Optical Subassembly

Modular Low-Heater-Power Cathode/Electron Gun Assembly for Microwave and Millimeter Wave Traveling Wave Tubes

Science.gov (United States)

Wintucky, Edwin G.

2000-01-01

A low-cost, low-mass, electrically efficient, modular cathode/electron gun assembly has been developed by FDE Inc. of Beaverton, Oregon, under a Small Business Innovation Research (SBIR) contract with the NASA Glenn Research Center at Lewis Field. This new assembly offers significant improvements in the design and manufacture of microwave and millimeter wave traveling-wave tubes (TWT's) used for radar and communications. It incorporates a novel, low-heater-power, reduced size and mass, high-performance barium dispenser type thermionic cathode and provides for easy integration of the cathode into a large variety of conventional TWT circuits. Among the applications are TWT's for Earth-orbiting communication satellites and for deep space communications, where future missions will require smaller spacecraft, higher data transfer rates (higher frequencies and radiofrequency output power), and greater electrical efficiency. A particularly important TWT application is in the microwave power module (a hybrid microwave/millimeter wave amplifier consisting of a low-noise solid-state driver, a small TWT, and an electronic power conditioner integrated into a single compact package), where electrical efficiency and thermal loading are critical factors and lower cost is needed for successful commercialization. The design and fabrication are based on practices used in producing cathode ray tubes (CRT's), which is one of the most competitive and efficient manufacturing operations in the world today. The approach used in the design and manufacture of thermionic cathodes and electron guns for CRT's has been optimized for fully automated production, standardization of parts, and minimization of costs. It is applicable to the production of similar components for microwave tubes, with the additional benefits of low mass and significantly lower cathode heater power (less than half that of dispenser cathodes presently used in TWT s). Modular cathode/electron gun assembly. The modular

A Low-Cost, Precision Hydrometer for Classroom Use.

Science.gov (United States)

Murphy, Michael D.

1983-01-01

Describes a low cost hydrometer which can be assembled by students using stock laboratory items with a total retail cost of 17 cents. Includes list of required materials (with supplies) and experimental results on the instrument's accuracy. (JM)

The zebrafish world of colors and shapes: preference and discrimination.

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Oliveira, Jessica; Silveira, Mayara; Chacon, Diana; Luchiari, Ana

2015-04-01

Natural environment imposes many challenges to animals, which have to use cognitive abilities to cope with and exploit it to enhance their fitness. Since zebrafish is a well-established model for cognitive studies and high-throughput screening for drugs and diseases that affect cognition, we tested their ability for ambient color preference and 3D objects discrimination to establish a protocol for memory evaluation. For the color preference test, zebrafish were observed in a multiple-chamber tank with different environmental color options. Zebrafish showed preference for blue and green, and avoided yellow and red. For the 3D objects discrimination, zebrafish were allowed to explore two equal objects and then observed in a one-trial test in which a new color, size, or shape of the object was presented. Zebrafish showed discrimination for color, shape, and color+shape combined, but not size. These results imply that zebrafish seem to use some categorical system to discriminate items, and distracters affect their ability for discrimination. The type of variables available (color and shape) may favor zebrafish objects perception and facilitate discrimination processing. We suggest that this easy and simple memory test could serve as a useful screening tool for cognitive dysfunction and neurotoxicological studies.

Impact of low-dose chronic exposure to Bisphenol A (BPA) on adult male zebrafish adaption to the environmental complexity: Disturbing the color preference patterns and reliving the anxiety behavior.

Science.gov (United States)

Li, Xiang; Sun, Ming-Zhu; Li, Xu; Zhang, Shu-Hui; Dai, Liang-Ti; Liu, Xing-Yu; Zhao, Xin; Chen, Dong-Yan; Feng, Xi-Zeng

2017-11-01

The extensive usage of xenobiotic endocrine disrupting chemicals (XEDCs), such as Bisphenol A (BPA), has created obvious threat to aquatic ecosystems worldwide. Although a comprehensive understanding of the adverse effect of BPA on behaviors and physiology have been proven, the potential impact of low-dose BPA on altering the basic ability of aquatic organism in adapting to the surrounded complex environment still remains elusive. In this research, we report that treatment of adult male zebrafish with chronic (7 weeks) low-dose (0.22 nM-2.2 nM) BPA, altered the ability in adapting the complex environment by disturbing the natural color preference patterns. In addition, chronic 50 ng/L (0.22 nM) BPA exposure alleviated the anxiety behavior of male zebrafish confronted with the novel environment by enhancing the preference towards light in the light/dark preference test. This phenotype was associated with less expression of serotonin (5-TH) in the hypothalamus and the down-regulation of tyrosine hydroxylase (TH) in brain tissues. As such, our results show that low-dose BPA remnant in surface waters altered zebrafish behavior that are known to have ecological and evolutionary consequences. Here we reported that the impact of chronic low-dose BPA exposure on the basic capability of zebrafish to adapt to the environmental complexity. Specifically, BPA at low concentration, under the environmental safety level and 3000-fold lower than the accepted human daily exposure, interfered with the ability to discriminate color and alleviate anxiety induced by the novel environment, which finally altered the capability of male zebrafish to adapt to the environmental complexity. These findings revealed the ecological effect of low-dose BPA and regular BPA concentration standard are not necessarily safe. The result also provided the consideration of retuning the hazard concentration level of BPA. Copyright © 2017 Elsevier Ltd. All rights reserved.

Toxicity assessment of zebrafish following exposure to CdTe QDs

Energy Technology Data Exchange (ETDEWEB)

Zhang, Wei, E-mail: wzhang@ecust.edu.cn [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237 (China); Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237 (China); School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237 (China); Lin, Kuangfei, E-mail: kflin@ecust.edu.cn [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237 (China); Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237 (China); School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237 (China); Miao, Youna [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237 (China); Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237 (China); School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237 (China); Dong, Qiaoxiang; Huang, Changjiang; Wang, Huili [Zhejiang Provincial Key Lab for Technology and Application of Model Organisms, Wenzhou Medical College, Wenzhou 325035 (China); Guo, Meijin [State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237 (China); Cui, Xinhong [Shanghai Institute of Landscape Gardening, Shanghai 200233 (China)

2012-04-30

Highlights: Black-Right-Pointing-Pointer The LC{sub 50} of TGA-CdTe for zebrafish at 120 hpf was 185.9 nM. Black-Right-Pointing-Pointer Zebrafish exposed to TGA-CdTe resulted in lower hatch rate and more malformation. Black-Right-Pointing-Pointer Body length and heart beat of zebrafish declined after exposure to TGA-CdTe. Black-Right-Pointing-Pointer Larvae exposure to TGA-CdTe elicited a higher basal swimming rate. Black-Right-Pointing-Pointer Abnormal vascular of FLI-1 transgenic zebrafish larvae exposed to TGA-CdTe occurred. - Abstract: CdTe quantum dots (QDs) are nanocrystals of unique composition and properties that have found many new commercial applications; therefore, their potential toxicity to aquatic organisms has become a hot research topic. The lab study was performed to determine the developmental and behavioral toxicities to zebrafish under continuous exposure to low concentrations of CdTe QDs (1-400 nM) coated with thioglycolic acid (TGA). The results show: (1) the 120 h LC{sub 50} of 185.9 nM, (2) the lower hatch rate and body length, more malformations, and less heart beat and swimming speed of the exposed zebrafish, (3) the brief burst and a higher basal swimming rate of the exposed zebrafish larvae during a rapid transition from light-to-dark, and (4) the vascular hyperplasia, vascular bifurcation, vascular crossing and turbulence of the exposed FLI-1 transgenic zebrafish larvae.

The French press: a repeatable and high-throughput approach to exercising zebrafish (Danio rerio).

Science.gov (United States)

Usui, Takuji; Noble, Daniel W A; O'Dea, Rose E; Fangmeier, Melissa L; Lagisz, Malgorzata; Hesselson, Daniel; Nakagawa, Shinichi

2018-01-01

Zebrafish are increasingly used as a vertebrate model organism for various traits including swimming performance, obesity and metabolism, necessitating high-throughput protocols to generate standardized phenotypic information. Here, we propose a novel and cost-effective method for exercising zebrafish, using a coffee plunger and magnetic stirrer. To demonstrate the use of this method, we conducted a pilot experiment to show that this simple system provides repeatable estimates of maximal swim performance (intra-class correlation [ICC] = 0.34-0.41) and observe that exercise training of zebrafish on this system significantly increases their maximum swimming speed. We propose this high-throughput and reproducible system as an alternative to traditional linear chamber systems for exercising zebrafish and similarly sized fishes.

Screening in larval zebrafish reveals tissue-specific distribution of fifteen fluorescent compounds

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Yuxiao Yao

2017-09-01

Full Text Available The zebrafish is a prominent vertebrate model for low-cost in vivo whole organism screening. In our recent screening of the distribution patterns of fluorescent compounds in live zebrafish larvae, fifteen compounds with tissue-specific distributions were identified. Several compounds were observed to accumulate in tissues where they were reported to induce side-effects, and compounds with similar structures tended to be enriched in the same tissues, with minor differences. In particular, we found three novel red fluorescent bone-staining dyes: purpurin, lucidin and 3-hydroxy-morindone; purpurin can effectively label bones in both larval and adult zebrafish, as well as in postnatal mice, without significantly affecting bone mass and density. Moreover, two structurally similar chemotherapeutic compounds, doxorubicin and epirubicin, were observed to have distinct distribution preferences in zebrafish. Epirubicin maintained a relatively higher concentration in the liver, and performed better in inhibiting hepatic hyperplasia caused by the over-expression of krasG12V. In total, our study suggests that the transparent zebrafish larvae serve as valuable tools for identifying tissue-specific distributions of fluorescent compounds.

Developmental exposure to low concentrations of two brominated flame retardants, BDE-47 and BDE-99, causes life-long behavioral alterations in zebrafish.

Science.gov (United States)

Glazer, Lilah; Wells, Corinne N; Drastal, Meghan; Odamah, Kathryn-Ann; Galat, Richard E; Behl, Mamta; Levin, Edward D

2018-05-01

Polybrominated diphenyl ethers (PBDEs) were widely used as flame retardants until the early 2000s, mainly in home furnishings and electronics. The persistence of PBDEs in the environment leads to continued ubiquitous exposure to low levels, with infants and children experiencing higher exposures than adults. Accumulating evidence suggest that low-level exposures during early life stages can affect brain development and lead to long-term behavioral impairments. We investigated the effects of zebrafish exposure to low doses of the two prominent PBDEs; 2,2',4,4',5,-Pentabromodiphenyl ether (BDE-99) and 2,2',4,4',-Tetrabromodiphenyl ether (BDE-47), during embryo-development on short- and long-term behavioral endpoints. We included the organophosphate pesticide chlorpyrifos (CPF) due to its well documented neurotoxicity across species from zebrafish to humans. Zebrafish embryos were exposed to the following individual treatments; 0.1% DMSO (vehicle control); 0.3μM CPF; 0.01, 0.03, 0.1, 0.3μM BDE-47; 0.003, 0.03, 0.3, 1, 3, 10, 20μM BDE-99 from 5 until 120h post fertilization (hpf). Low exposure levels were determined as those not causing immediate overt toxicity, and behavior assays were conducted in the low-level range. At 144 hpf the larvae were tested for locomotor activity. At approximately 6 months of age adult zebrafish were tested in a behavioral battery including assays for anxiety-related behavior, sensorimotor response and habituation, social interaction, and predator avoidance. In the short-term, larval locomotor activity was reduced in larvae treated with 0.3μM CPF and 0.1μM BDE-47. BDE-99 treatment caused non-monotonic dose effects, with 0.3μM causing hyperactivity and 1μM or higher causing hypoactivity. In the long-term, adult anxiety-related behavior was reduced in all treatments as measured in both the novel tank dive test and tap test. We show that exposure of zebrafish embryos to low concentrations of the brominated flame retardants BDE-47 and

Using local chromatin structure to improve CRISPR/Cas9 efficiency in zebrafish.

Science.gov (United States)

Chen, Yunru; Zeng, Shiyang; Hu, Ruikun; Wang, Xiangxiu; Huang, Weilai; Liu, Jiangfang; Wang, Luying; Liu, Guifen; Cao, Ying; Zhang, Yong

2017-01-01

Although the CRISPR/Cas9 has been successfully applied in zebrafish, considerable variations in efficiency have been observed for different gRNAs. The workload and cost of zebrafish mutant screening is largely dependent on the mutation rate of injected embryos; therefore, selecting more effective gRNAs is especially important for zebrafish mutant construction. Besides the sequence features, local chromatin structures may have effects on CRISPR/Cas9 efficiency, which remain largely unexplored. In the only related study in zebrafish, nucleosome organization was not found to have an effect on CRISPR/Cas9 efficiency, which is inconsistent with recent studies in vitro and in mammalian cell lines. To understand the effects of local chromatin structure on CRISPR/Cas9 efficiency in zebrafish, we first determined that CRISPR/Cas9 introduced genome editing mainly before the dome stage. Based on this observation, we reanalyzed our published nucleosome organization profiles and generated chromatin accessibility profiles in the 256-cell and dome stages using ATAC-seq technology. Our study demonstrated that chromatin accessibility showed positive correlation with CRISPR/Cas9 efficiency, but we did not observe a clear correlation between nucleosome organization and CRISPR/Cas9 efficiency. We constructed an online database for zebrafish gRNA selection based on local chromatin structure features that could prove beneficial to zebrafish homozygous mutant construction via CRISPR/Cas9.

An easy, low-cost method to transfer large-scale graphene onto polyethylene terephthalate as a transparent conductive flexible substrate

International Nuclear Information System (INIS)

Chen, Chih-Sheng; Hsieh, Chien-Kuo

2014-01-01

In this study, we develop a low-cost method for transferring a large-scale graphene film onto a flexible transparent substrate. An easily accessible method for home-made chemical vapor deposition (CVD) and a commercial photograph laminator were utilized to fabricate the low-cost graphene-based transparent conductive flexible substrate. The graphene was developed based on CVD growth on nickel foil using a carbon gas source, and the graphene thin film was easily transferred onto the laminating film via a heated photograph laminator. Field emission scanning electron microscopy and atomic force microscopy were utilized to examine the morphological characteristics of the graphene surface. Raman spectroscopy and transmission electron microscopy were utilized to examine the microstructure of the graphene. The optical–electronic properties of the transferred graphene flexible thin film were measured by ultraviolet–visible spectrometry and a four-point probe. The advantage of this method is that large-scale graphene-based thin films can be easily obtained. We provide an economical method for fabricating a graphene-based transparent conductive flexible substrate. - Highlight: • We synthesized the large-scale graphene by thermal CVD method. • A low-cost commercial photograph laminator was used to transfer graphene. • A large-scale transparent and flexible graphene substrate was obtained easily

An easy, low-cost method to transfer large-scale graphene onto polyethylene terephthalate as a transparent conductive flexible substrate

Energy Technology Data Exchange (ETDEWEB)

Chen, Chih-Sheng; Hsieh, Chien-Kuo, E-mail: jack_hsieh@mail.mcut.edu.tw

2014-11-03

In this study, we develop a low-cost method for transferring a large-scale graphene film onto a flexible transparent substrate. An easily accessible method for home-made chemical vapor deposition (CVD) and a commercial photograph laminator were utilized to fabricate the low-cost graphene-based transparent conductive flexible substrate. The graphene was developed based on CVD growth on nickel foil using a carbon gas source, and the graphene thin film was easily transferred onto the laminating film via a heated photograph laminator. Field emission scanning electron microscopy and atomic force microscopy were utilized to examine the morphological characteristics of the graphene surface. Raman spectroscopy and transmission electron microscopy were utilized to examine the microstructure of the graphene. The optical–electronic properties of the transferred graphene flexible thin film were measured by ultraviolet–visible spectrometry and a four-point probe. The advantage of this method is that large-scale graphene-based thin films can be easily obtained. We provide an economical method for fabricating a graphene-based transparent conductive flexible substrate. - Highlight: • We synthesized the large-scale graphene by thermal CVD method. • A low-cost commercial photograph laminator was used to transfer graphene. • A large-scale transparent and flexible graphene substrate was obtained easily.

Easy-to-Use UAV Ground Station Software for Low-Altitude Civil Operations, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — We propose to design and develop easy-to-use Ground Control Station (GCS) software for low-altitude civil Unmanned Aerial Vehicle (UAV) operations. The GCS software...

Zebrafish: an animal model for research in veterinary medicine.

Science.gov (United States)

Nowik, N; Podlasz, P; Jakimiuk, A; Kasica, N; Sienkiewicz, W; Kaleczyc, J

2015-01-01

The zebrafish (Danio rerio) has become known as an excellent model organism for studies of vertebrate biology, vertebrate genetics, embryonal development, diseases and drug screening. Nevertheless, there is still lack of detailed reports about usage of the zebrafish as a model in veterinary medicine. Comparing to other vertebrates, they can lay hundreds of eggs at weekly intervals, externally fertilized zebrafish embryos are accessible to observation and manipulation at all stages of their development, which makes possible to simplify the research techniques such as fate mapping, fluorescent tracer time-lapse lineage analysis and single cell transplantation. Although zebrafish are only 2.5 cm long, they are easy to maintain. Intraperitoneal and intracerebroventricular injections, blood sampling and measurement of food intake are possible to be carry out in adult zebrafish. Danio rerio is a useful animal model for neurobiology, developmental biology, drug research, virology, microbiology and genetics. A lot of diseases, for which the zebrafish is a perfect model organism, affect aquatic animals. For a part of them, like those caused by Mycobacterium marinum or Pseudoloma neutrophila, Danio rerio is a natural host, but the zebrafish is also susceptible to the most of fish diseases including Itch, Spring viraemia of carp and Infectious spleen and kidney necrosis. The zebrafish is commonly used in research of bacterial virulence. The zebrafish embryo allows for rapid, non-invasive and real time analysis of bacterial infections in a vertebrate host. Plenty of common pathogens can be examined using zebrafish model: Streptococcus iniae, Vibrio anguillarum or Listeria monocytogenes. The steps are taken to use the zebrafish also in fungal research, especially that dealing with Candida albicans and Cryptococcus neoformans. Although, the zebrafish is used commonly as an animal model to study diseases caused by external agents, it is also useful in studies of metabolic

Quo natas, Danio?—Recent Progress in Modeling Cancer in Zebrafish

Directory of Open Access Journals (Sweden)

Stefanie Kirchberger

2017-08-01

Full Text Available Over the last decade, zebrafish has proven to be a powerful model in cancer research. Zebrafish form tumors that histologically and genetically resemble human cancers. The live imaging and cost-effective compound screening possible with zebrafish especially complement classic mouse cancer models. Here, we report recent progress in the field, including genetically engineered zebrafish cancer models, xenotransplantation of human cancer cells into zebrafish, promising approaches toward live investigation of the tumor microenvironment, and identification of therapeutic strategies by performing compound screens on zebrafish cancer models. Given the recent advances in genome editing, personalized zebrafish cancer models are now a realistic possibility. In addition, ongoing automation will soon allow high-throughput compound screening using zebrafish cancer models to be part of preclinical precision medicine approaches.

Self-assembled peptide nanostructures for the development of electrochemical biosensors

DEFF Research Database (Denmark)

Castillo-León, Jaime; Zor, Kinga; Svendsen, Winnie Edith

2015-01-01

. These biological nanostructures have recently been utilized for bionanotechnological applications thanks to their easy and low-cost fabrication, their stability, and their facile functionalization. These features suggest the usage of self-assembled peptide nanostructures in the development of biosensing platforms......Biological building blocks such as peptides or proteins are able to self-organize into nanostructures with particular properties. There are several possibilities for their use in varying applications such as drug delivery, biosensing, clean-room fabrication methods, and tissue engineering...

Skin too thin? The developing utility of zebrafish skin (neuro)pharmacology for CNS drug discovery research.

Science.gov (United States)

Nguyen, Michael; Poudel, Manoj K; Stewart, Adam Michael; Kalueff, Allan V

2013-09-01

Skin coloration can be affected by many genetic, environmental and pharmacological factors. Zebrafish (Danio rerio) are a useful and versatile model organism in biomedical research due to their genetic tractability, physiological homology to mammals, low cost, reproducibility and high throughput. Zebrafish coloration is mediated by chromatophores - the skin color pigment cells largely controlled by endocrine and neural mechanisms. The characteristic darkening of zebrafish skin is caused by the dispersion (and paling - by aggregation) of melanosomes (pigment-containing organelles), which show high homology to mammalian structures. Various pharmacological agents potently affect zebrafish coloration - the phenotype that often accompanies behavioral effects of the drugs, and may be used for drug discovery. Although zebrafish behavior and skin responses are usually not directly related, they share common regulatory (neural, endocrine) mechanisms, and therefore may be assessed in parallel during psychotropic drug screening. For example, some psychoactive drugs can potently affect zebrafish skin coloration. Can we use this knowledge to refine phenotype-driven psychotropic drug discovery? Here, we present current models using zebrafish skin coloration assays, and discuss how these models may be applied to enhance in vivo CNS drug discovery. Copyright © 2013 Elsevier Inc. All rights reserved.

Primary Spinal OPC Culture System from Adult Zebrafish to Study Oligodendrocyte Differentiation In Vitro

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Volker Kroehne

2017-09-01

Full Text Available Endogenous oligodendrocyte progenitor cells (OPCs are a promising target to improve functional recovery after spinal cord injury (SCI by remyelinating denuded, and therefore vulnerable, axons. Demyelination is the result of a primary insult and secondary injury, leading to conduction blocks and long-term degeneration of the axons, which subsequently can lead to the loss of their neurons. In response to SCI, dormant OPCs can be activated and subsequently start to proliferate and differentiate into mature myelinating oligodendrocytes (OLs. Therefore, researchers strive to control OPC responses, and utilize small molecule screening approaches in order to identify mechanisms of OPC activation, proliferation, migration and differentiation. In zebrafish, OPCs remyelinate axons of the optic tract after lysophosphatidylcholine (LPC-induced demyelination back to full thickness myelin sheaths. In contrast to zebrafish, mammalian OPCs are highly vulnerable to excitotoxic stress, a cause of secondary injury, and remyelination remains insufficient. Generally, injury induced remyelination leads to shorter internodes and thinner myelin sheaths in mammals. In this study, we show that myelin sheaths are lost early after a complete spinal transection injury, but are re-established within 14 days after lesion. We introduce a novel, easy-to-use, inexpensive and highly reproducible OPC culture system based on dormant spinal OPCs from adult zebrafish that enables in vitro analysis. Zebrafish OPCs are robust, can easily be purified with high viability and taken into cell culture. This method enables to examine why zebrafish OPCs remyelinate better than their mammalian counterparts, identify cell intrinsic responses, which could lead to pro-proliferating or pro-differentiating strategies, and to test small molecule approaches. In this methodology paper, we show efficient isolation of OPCs from adult zebrafish spinal cord and describe culture conditions that enable

Low-cost solar array structure development

Science.gov (United States)

Wilson, A. H.

1981-06-01

Early studies of flat-plate arrays have projected costs on the order of $50/square meter for installed array support structures. This report describes an optimized low-cost frame-truss structure that is estimated to cost below $25/square meter, including all markups, shipping an installation. The structure utilizes a planar frame made of members formed from light-gauge galvanized steel sheet and is supposed in the field by treated-wood trusses that are partially buried in trenches. The buried trusses use the overburden soil to carry uplift wind loads and thus to obviate reinforced-concrete foundations. Details of the concept, including design rationale, fabrication and assembly experience, structural testing and fabrication drawings are included.

ZebrafishMiner: an open source software for interactive evaluation of domain-specific fluorescence in zebrafish

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Reischl Markus

2017-09-01

Full Text Available High-throughput microscopy makes it possible to observe the morphology of zebrafish on large scale to quantify genetic, toxic or drug effects. The image acquisition is done by automated microscopy, images are evaluated automatically by image processing pipelines, tailored specifically to the requirements of the scientific question. The transfer of such algorithms to other projects, however, is complex due to missing guidelines and lack of mathematical or programming knowledge. In this work, we implement an image processing pipeline for automatic fluorescence quantification in user-defined domains of zebrafish embryos and larvae of different age. The pipeline is capable of detecting embryos and larvae in image stacks and quantifying domain activity. To make this protocol available to the community, we developed an open source software package called „ZebrafishMiner“ which guides the user through all steps of the processing pipeline and makes the algorithms available and easy to handle. We implemented all routines in an MATLAB-based graphical user interface (GUI that gives the user control over all image processing parameters. The software is shipped with a manual of 30 pages and three tutorial datasets, which guide the user through the manual step by step. It can be downloaded at https://sourceforge.net/projects/scixminer/.

Large-scale assessment of the zebrafish embryo as a possible predictive model in toxicity testing.

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Shaukat Ali

Full Text Available BACKGROUND: In the drug discovery pipeline, safety pharmacology is a major issue. The zebrafish has been proposed as a model that can bridge the gap in this field between cell assays (which are cost-effective, but low in data content and rodent assays (which are high in data content, but less cost-efficient. However, zebrafish assays are only likely to be useful if they can be shown to have high predictive power. We examined this issue by assaying 60 water-soluble compounds representing a range of chemical classes and toxicological mechanisms. METHODOLOGY/PRINCIPAL FINDINGS: Over 20,000 wild-type zebrafish embryos (including controls were cultured individually in defined buffer in 96-well plates. Embryos were exposed for a 96 hour period starting at 24 hours post fertilization. A logarithmic concentration series was used for range-finding, followed by a narrower geometric series for LC(50 determination. Zebrafish embryo LC(50 (log mmol/L, and published data on rodent LD(50 (log mmol/kg, were found to be strongly correlated (using Kendall's rank correlation tau and Pearson's product-moment correlation. The slope of the regression line for the full set of compounds was 0.73403. However, we found that the slope was strongly influenced by compound class. Thus, while most compounds had a similar toxicity level in both species, some compounds were markedly more toxic in zebrafish than in rodents, or vice versa. CONCLUSIONS: For the substances examined here, in aggregate, the zebrafish embryo model has good predictivity for toxicity in rodents. However, the correlation between zebrafish and rodent toxicity varies considerably between individual compounds and compound class. We discuss the strengths and limitations of the zebrafish model in light of these findings.

Definition of the zebrafish genome using flow cytometry and cytogenetic mapping

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Zhou Yi

2007-06-01

Full Text Available Abstract Background The zebrafish (Danio rerio is an important vertebrate model organism system for biomedical research. The syntenic conservation between the zebrafish and human genome allows one to investigate the function of human genes using the zebrafish model. To facilitate analysis of the zebrafish genome, genetic maps have been constructed and sequence annotation of a reference zebrafish genome is ongoing. However, the duplicative nature of teleost genomes, including the zebrafish, complicates accurate assembly and annotation of a representative genome sequence. Cytogenetic approaches provide "anchors" that can be integrated with accumulating genomic data. Results Here, we cytogenetically define the zebrafish genome by first estimating the size of each linkage group (LG chromosome using flow cytometry, followed by the cytogenetic mapping of 575 bacterial artificial chromosome (BAC clones onto metaphase chromosomes. Of the 575 BAC clones, 544 clones localized to apparently unique chromosomal locations. 93.8% of these clones were assigned to a specific LG chromosome location using fluorescence in situ hybridization (FISH and compared to the LG chromosome assignment reported in the zebrafish genome databases. Thirty-one BAC clones localized to multiple chromosomal locations in several different hybridization patterns. From these data, a refined second generation probe panel for each LG chromosome was also constructed. Conclusion The chromosomal mapping of the 575 large-insert DNA clones allows for these clones to be integrated into existing zebrafish mapping data. An accurately annotated zebrafish reference genome serves as a valuable resource for investigating the molecular basis of human diseases using zebrafish mutant models.

Low-Cost Production of Photonic Bandgap Materials Through Bubbling

National Research Council Canada - National Science Library

O'Brien, Daniel J; Wetzel, Eric D

2007-01-01

.... This report proposes a simple low-cost method for PBGM production. A device has been constructed that produces micrometer-sized, monodisperse bubbles that can be assembled into a crystal lattice by surface tension...

easySTORM: a robust, lower-cost approach to localisation and TIRF microscopy.

Science.gov (United States)

Kwakwa, Kwasi; Savell, Alexander; Davies, Timothy; Munro, Ian; Parrinello, Simona; Purbhoo, Marco A; Dunsby, Chris; Neil, Mark A A; French, Paul M W

2016-09-01

TIRF and STORM microscopy are super-resolving fluorescence imaging modalities for which current implementations on standard microscopes can present significant complexity and cost. We present a straightforward and low-cost approach to implement STORM and TIRF taking advantage of multimode optical fibres and multimode diode lasers to provide the required excitation light. Combined with open source software and relatively simple protocols to prepare samples for STORM, including the use of Vectashield for non-TIRF imaging, this approach enables TIRF and STORM imaging of cells labelled with appropriate dyes or expressing suitable fluorescent proteins to become widely accessible at low cost. © 2016 The Authors. Journal of Biophotonics published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Zebrafish Health Conditions in the China Zebrafish Resource Center and 20 Major Chinese Zebrafish Laboratories.

Science.gov (United States)

Liu, Liyue; Pan, Luyuan; Li, Kuoyu; Zhang, Yun; Zhu, Zuoyan; Sun, Yonghua

2016-07-01

In China, the use of zebrafish as an experimental animal in the past 15 years has widely expanded. The China Zebrafish Resource Center (CZRC), which was established in 2012, is becoming one of the major resource centers in the global zebrafish community. Large-scale use and regular exchange of zebrafish resources have put forward higher requirements on zebrafish health issues in China. This article reports the current aquatic infrastructure design, animal husbandry, and health-monitoring programs in the CZRC. Meanwhile, through a survey of 20 Chinese zebrafish laboratories, we also describe the current health status of major zebrafish facilities in China. We conclude that it is of great importance to establish a widely accepted health standard and health-monitoring strategy in the Chinese zebrafish research community.

Zebrafish kidney phagocytes utilize macropinocytosis and Ca+-dependent endocytic mechanisms.

Directory of Open Access Journals (Sweden)

Claudia Hohn

Full Text Available BACKGROUND: The innate immune response constitutes the first line of defense against invading pathogens and consists of a variety of immune defense mechanisms including active endocytosis by macrophages and granulocytes. Endocytosis can be used as a reliable measure of selective and non-selective mechanisms of antigen uptake in the early phase of an immune response. Numerous assays have been developed to measure this response in a variety of mammalian and fish species. The small size of the zebrafish has prevented the large-scale collection of monocytes/macrophages and granulocytes for these endocytic assays. METHODOLOGY/PRINCIPAL FINDINGS: Pooled zebrafish kidney hematopoietic tissues were used as a source of phagocytic cells for flow-cytometry based endocytic assays. FITC-Dextran, Lucifer Yellow and FITC-Edwardsiella ictaluri were used to evaluate selective and non-selective mechanisms of uptake in zebrafish phagocytes. CONCLUSIONS/SIGNIFICANCE: Zebrafish kidney phagocytes characterized as monocytes/macrophages, neutrophils and lymphocytes utilize macropinocytosis and Ca(2+-dependant endocytosis mechanisms of antigen uptake. These cells do not appear to utilize a mannose receptor. Heat-killed Edwardsiella ictaluri induces cytoskeletal interactions for internalization in zebrafish kidney monocytes/macrophages and granulocytes. The proposed method is easy to implement and should prove especially useful in immunological, toxicological and epidemiological research.

Final Report - High Performance, Durable, Low Cost Membrane Electrode Assemblies for Transportation Applications

Energy Technology Data Exchange (ETDEWEB)

Steinbach, Andrew [3M Company, Maplewood, MN (United States)

2017-05-31

The primary project objective was development of improved polymer electrolyte membrane fuel cell (PEMFC) membrane electrode assemblies (MEAs) which address the key DOE barriers of performance, durability and cost. Additional project objectives were to address commercialization barriers specific to MEAs comprising 3M nanostructured thin film (NSTF) electrodes, including a larger-than-acceptable sensitivity to operating conditions, an unexplained loss of rated power capability with operating time, and slow break-in conditioning. Significant progress was made against each of these barriers, and most DOE 2020 targets were met or substantially approached.

Implementation of a Low-Cost Automated LED Photometer for Enzymatic Reaction Detection to Teach Basic Bioelectronics Technologies in Vocational High Schools

Science.gov (United States)

Chen, Huai-Yi; Nieh, Hwa-Ming; Yang, Ming-Feng; Chou, Yu-Kung; Chung, Jui-Hsu; Liou, Je-Wen

2016-01-01

This study proposes a home-assembled, low-cost blue light-emitting diode (LED) photometer that uses simple and low-cost hardware and software, costing about US $150. This 425-nm wavelength photometer is controlled by an 89C51 microcontroller chip. Glucose concentration detection experiments involving enzyme coupling reactions were carried out to…

Light-Controlled Swarming and Assembly of Colloidal Particles

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Jianhua Zhang

2018-02-01

Full Text Available Swarms and assemblies are ubiquitous in nature and they can perform complex collective behaviors and cooperative functions that they cannot accomplish individually. In response to light, some colloidal particles (CPs, including light active and passive CPs, can mimic their counterparts in nature and organize into complex structures that exhibit collective functions with remote controllability and high temporospatial precision. In this review, we firstly analyze the structural characteristics of swarms and assemblies of CPs and point out that light-controlled swarming and assembly of CPs are generally achieved by constructing light-responsive interactions between CPs. Then, we summarize in detail the recent advances in light-controlled swarming and assembly of CPs based on the interactions arisen from optical forces, photochemical reactions, photothermal effects, and photoisomerizations, as well as their potential applications. In the end, we also envision some challenges and future prospects of light-controlled swarming and assembly of CPs. With the increasing innovations in mechanisms and control strategies with easy operation, low cost, and arbitrary applicability, light-controlled swarming and assembly of CPs may be employed to manufacture programmable materials and reconfigurable robots for cooperative grasping, collective cargo transportation, and micro- and nanoengineering.

New tides: using zebrafish to study renal regeneration.

Science.gov (United States)

McCampbell, Kristen K; Wingert, Rebecca A

2014-02-01

Over the past several decades, the zebrafish has become one of the major vertebrate model organisms used in biomedical research. In this arena, the zebrafish has emerged as an applicable system for the study of kidney diseases and renal regeneration. The relevance of the zebrafish model for nephrology research has been increasingly appreciated as the understanding of zebrafish kidney structure, ontogeny, and the response to damage has steadily expanded. Recent studies have documented the amazing regenerative characteristics of the zebrafish kidney, which include the ability to replace epithelial populations after acute injury and to grow new renal functional units, termed nephrons. Here we discuss how nephron composition is conserved between zebrafish and mammals, and highlight how recent findings from zebrafish studies utilizing transgenic technologies and chemical genetics can complement traditional murine approaches in the effort to dissect how the kidney responds to acute damage and identify therapeutics that enhance human renal regeneration. Copyright © 2014 Mosby, Inc. All rights reserved.

Wet-process Fabrication of Low-cost All-solid Wire-shaped Solar Cells on Manganese-plated Electrodes

International Nuclear Information System (INIS)

Fan, Xing; Zhang, Xiaoying; Zhang, Nannan; Cheng, Li; Du, Jun; Tao, Changyuan

2015-01-01

Highlights: • All-solid wire-shaped flexible solar cells are firstly assembled on low-cost Mn-plated fibers. • Energy efficiency improved by >27% after coating a layer of Mn on various substrates. • The cell is fabricated via wet process under low temperature and mild pH conditions. • Stable flexible solar cells are realized on lightweight and low-cost polymer fiber. - Abstract: All-solid wire-shaped flexible solar cells are assembled for the first time on low-cost Mn-plated wires through wet-process fabrication under low temperature and mild pH conditions. With a price cheap as the steel, metal Mn can be easily plated on almost any substrates, and evidently promote the photovoltaic efficiency of wire-shaped solar cells on various traditional metal wire substrates, such as Fe and Ti, by 27% and 65%, respectively. Flexible solar cell with much lower cost and weight is assembled on Mn-plated polymer substrate, and is still capable of giving better performance than that on Fe or Ti substrate. Both its mechanical and chemical stability are good for future weaving applications. Owing to the wire-type structure, such low-cost metals as Mn, which are traditionally regarded as unsuitable for solar cells, may provide new opportunities for highly efficient solar cells

An Open-source Low-cost Portable Apparatus for Soil Fauna Sampling

Science.gov (United States)

Daliakopoulos, Ioannis; Wagner, Karl; Grillakis, Manolis; Apostolakis, Antonios; Tsanis, Ioannis

2016-04-01

A low-cost apparatus for the extraction of living soil animals from soil or litter samples is presented. The main unit consists of a modular bank system with three horizontal shelves designed to accommodate lamps and soil samples over funnel and jar systems for animal collection, thus serving as a practical and standardized modification of the well-documented Berlese-Tullgren funnel. Shelves are vertically adjustable, sliding on 5 mm threaded rods and securing with wing nuts for easy assembly/disassembly and stability. Shelf material is 4 mm plywood (or similar), laser-cut (or similar) to accommodate lamp sockets, tubes and funnels at respective levels. Soil samples are inserted in 10 cm tubes from standard Ø50 mm PVC piping that can also function as direct collection corers for softer soils. Tubes are fitted in the tube bank shelf, each directly under a 25 W reflector lamp and over a funnel and jar system. Lamps are located 25 mm over the tubes' top creating a relatively constant 10 oC temperature gradient that drives soil animals away from heat and light, and towards the bottom end of the tube which is fitted with a suitable fabric mesh. Standard 106 ml panelled jars, filled with a safe-to-handle preservative (e.g. propylene glycol) to the lower end of the funnel fitted in them, trap and preserve soil organisms until identification. The apparatus offers flat-pack portability and scalability using low-cost standard material. Design specifications and Drawing eXchange Format (dxf) files for apparatus reproduction are provided.

Single Low-Dose Ionizing Radiation Induces Genotoxicity in Adult Zebrafish and its Non-Irradiated Progeny.

Science.gov (United States)

Lemos, J; Neuparth, T; Trigo, M; Costa, P; Vieira, D; Cunha, L; Ponte, F; Costa, P S; Metello, L F; Carvalho, A P

2017-02-01

This study investigated to what extent a single exposure to low doses of ionizing radiation can induce genotoxic damage in irradiated adult zebrafish (Danio rerio) and its non-irradiated F1 progeny. Four groups of adult zebrafish were irradiated with a single dose of X-rays at 0 (control), 100, 500 and 1000 mGy, respectively, and couples of each group were allowed to reproduce following irradiation. Blood of parental fish and whole-body offspring were analysed by the comet assay for detection of DNA damage. The level of DNA damage in irradiated parental fish increased in a radiation dose-dependent manner at day 1 post-irradiation, but returned to the control level thereafter. The level of DNA damage in the progeny was directly correlated with the parental irradiation dose. Results highlight the genotoxic risk of a single exposure to low-dose ionizing radiation in irradiated individuals and also in its non-irradiated progeny.

A reduced transcriptome approach to assess environmental toxicants using zebrafish embryo tests

Science.gov (United States)

This paper reports on the pilot testing of a new bioassay platform that monitors expression of 1600 genes in zebrafish embryos exposed to either single chemicals or complex water samples. The method provides a more cost effective, high throughput means to broadly evaluate the pot...

In Vivo Nanotoxicity Testing using the Zebrafish Embryo Assay.

Science.gov (United States)

Rizzo, Larissa Y; Golombek, Susanne K; Mertens, Marianne E; Pan, Yu; Laaf, Dominic; Broda, Janine; Jayapaul, Jabadurai; Möckel, Diana; Subr, Vladimir; Hennink, Wim E; Storm, Gert; Simon, Ulrich; Jahnen-Dechent, Willi; Kiessling, Fabian; Lammers, Twan

2013-06-10

Nanoparticles are increasingly used for biomedical purposes. Many different diagnostic and therapeutic applications are envisioned for nanoparticles, but there are often also serious concerns regarding their safety. Given the fact that numerous new nanomaterials are being developed every day, and that not much is known about the long-term toxicological impact of exposure to nanoparticles, there is an urgent need to establish efficient methods for nanotoxicity testing. The zebrafish (Danio rerio) embryo assay has recently emerged as an interesting 'intermediate' method for in vivo nanotoxicity screening, enabling (semi-) high-throughput analyses in a system significantly more complex than cultured cells, but at the same time also less 'invasive' and less expensive than large-scale biocompatibility studies in mice or rats. The zebrafish embryo assay is relatively well-established in the environmental sciences, but it has not yet gained wide notice in the nanomedicine field. Using prototypic polymeric drug carriers, gold-based nanodiagnostics and nanotherapeutics, and iron oxide-based nanodiagnostics, we here show that toxicity testing using zebrafish embryos is easy, efficient and informative, and faithfully reflects, yet significantly extends, cell-based toxicity testing. We therefore expect that the zebrafish embryo assay will become a popular future tool for in vivo nanotoxicity screening.

Use of stainless stell for cost competitive bipolar plates in the SPFC

Energy Technology Data Exchange (ETDEWEB)

Makkus, R.C.; Janssen, A.H.H.; Bruijn, F.A. de; Mallant, R.K.A.M. [Netherlands Energy Research Foundation, Department of Fuels, Conversion and Environment, Petten (Netherlands)

2000-03-01

Bipolar plate materials for the Solid Polymer Fuel Cell (SPFC), alternative to the presently used graphite, should fulfil the following requirements in order to be applicable: low-cost, easy to machine or to shape, lightweight and low volume, mechanically and sufficiently chemically stable, and having a low contact resistance. Stainless steel is a low-cost material that is easy to shape, and thin sheets can be used to yield low volume and weight. Several stainless steels have been tested for their applicability (1.4439, 1.4404, 1.4541, 1.4529, 1.3974). The compaction pressure is of large influence on the contact resistance. Also, the pre-treatment of the surface is of influence; this is a permanent effect. Stainless steel constituents slowly dissolve into the Membrane Electrode Assembly (MEA). It has been found that the anode side stainless steel flow plate is the main source of contamination. Direct contact between the stainless steel and the membrane greatly enhances the contaminant level. Using an appropriate pre-treatment and a coating or gasket preventing direct contact between stainless steel and the membrane, one alloy was found to satisfy the requirements for use as a low cost material for the flow plate of an SPFC. (orig.)

A drying system for spent fuel assemblies

International Nuclear Information System (INIS)

Suikki, M.; Warinowski, M.; Nieminen, J.

2007-06-01

The report presents a proposed drying apparatus for spent fuel assemblies. The apparatus is used for removing the moisture left in fuel assemblies during intermediate storage and transport. The apparatus shall be installed in connection with the fuel handling cell of an encapsulation plant. The report presents basic requirements for and implementation of the drying system, calculation of the drying process, operation, service and maintenance of the equipment, as well as a cost estimate. Some aspects of the apparatus design are quite specified, but the actual detailed planning and final selection of components have not been included. The report also describes actions for possible malfunction and fault conditions. An objective of the drying system for fuel assemblies is to remove moisture from the assemblies prior to placing the same in a disposal canister for spent nuclear fuel. Drying is performed as a vacuum drying process for vaporizing and draining the moisture present on the surface of the assemblies. The apparatus comprises two pieces of drying equipment. One of the chambers is equipped to take up Lo1-2 fuel assemblies and the other OL1-2 fuel assemblies. The chambers have an internal space sufficient to accommodate also OL3 fuel assemblies, but this requires replacing the internal chamber structure for laying down the assemblies to be dried. The drying chambers can be closed with hatches facing the fuel handling cell. Water vapour pumped out of the chamber is collected in a controlled manner, first by condensing with a heat exchanger and further by freezing in a cold trap. For reasons of safety, the exhaust air of vacuum pumps is further delivered into the ventilation outlet duct of a controlled area. The adequate drying result is ascertained by a low final pressure of about 100 Pa, as well as by a sufficient holding time. The chamber is built for making its cleaning as easy as possible in the event of a fuel rod breaking during a drying, loading or unloading

Zebrafish as a potential model organism for drug test against hepatitis C virus.

Directory of Open Access Journals (Sweden)

Cun-Bao Ding

Full Text Available Screening and evaluating anti- hepatitis C virus (HCV drugs in vivo is difficult worldwide, mainly because of the lack of suitable small animal models. We investigate whether zebrafish could be a model organism for HCV replication. To achieve NS5B-dependent replication an HCV sub-replicon was designed and created with two vectors, one with HCV ns5b and fluorescent rfp genes, and the other containing HCV's 5'UTR, core, 3'UTR and fluorescent gfp genes. The vectors containing sub-replicons were co-injected into zebrafish zygotes. The sub-replicon amplified in liver showing a significant expression of HCV core RNA and protein. The sub-replicon amplification caused no abnormality in development and growth of zebrafish larvae, but induced gene expression change similar to that in human hepatocytes. As the amplified core fluorescence in live zebrafish was detectable microscopically, it rendered us an advantage to select those with replicating sub-replicon for drug experiments. Ribavirin and oxymatrine, two known anti-HCV drugs, inhibited sub-replicon amplification in this model showing reduced levels of HCV core RNA and protein. Technically, this method had a good reproducibility and is easy to operate. Thus, zebrafish might be a model organism to host HCV, and this zebrafish/HCV (sub-replicon system could be an animal model for anti-HCV drug screening and evaluation.

Glyphosate and Roundup® alter morphology and behavior in zebrafish.

Science.gov (United States)

Bridi, Daiane; Altenhofen, Stefani; Gonzalez, Jonas Brum; Reolon, Gustavo Kellermann; Bonan, Carla Denise

2017-12-01

Glyphosate has become the most widely used herbicide in the world, due to the wide scale adoption of transgenic glyphosate resistant crops after its introduction in 1996. Glyphosate may be used alone, but it is commonly applied as an active ingredient of the herbicide Roundup ® . This pesticide contains several adjuvants, which may promote an unknown toxicity. The indiscriminate application poses numerous problems, both for the health of the applicators and consumers, and for the environment, contaminating the soil, water and leading to the death of plants and animals. Zebrafish (Danio rerio) is quickly gaining popularity in behavioral research, because of physiological similarity to mammals, sensitivity to pharmacological factors, robust performance, low cost, short spawning intervals, external fertilization, transparency of embryos through larval stages, and rapid development. The aim of this study was evaluate the effects of glyphosate and Roundup ® on behavioral and morphological parameters in zebrafish larvae and adults. Zebrafish larvae at 3days post-fertilization and adults were exposed to glyphosate (0.01, 0.065, and 0.5mg/L) or Roundup ® (0.01, 0.065, and 0.5mg/L) for 96h. Immediately after the exposure, we performed the analysis of locomotor activity, aversive behavior, and morphology for the larvae and exploratory behavior, aggression and inhibitory avoidance memory for adult zebrafish. In zebrafish larvae, there were significant differences in the locomotor activity and aversive behavior after glyphosate or Roundup ® exposure when compared to the control group. Our findings demonstrated that exposure to glyphosate at the concentration of 0.5mg/L, Roundup ® at 0.065 or 0.5mg/L reduced the distance traveled, the mean speed and the line crossings in adult zebrafish. A decreased ocular distance was observed for larvae exposed at 0.5mg/L of glyphosate. We verified that at 0.5mg/L of Roundup ® -treated adult zebrafish demonstrated a significant

A homeostatic, chip-based platform for zebrafish larvae immobilization and long-term imaging

Science.gov (United States)

Friedrich, Timo; Zhu, Feng; Wlodkowic, Donald; Kaslin, Jan

2015-12-01

Zebrafish larvae are ideal for toxicology and drug screens due to their transparency, small size and similarity to humans on the genetic level. Using modern imaging techniques, cells and tissues can be dynamically visualised and followed over days in multiple zebrafish. Yet continued imaging experiments require specialized conditions such as: moisture and heat control to maintain specimen homeostasis. Chambers that control the environment are generally very expensive and are not always available for all imaging platforms. A highly customizable mounting configuration with built-in means of controlling temperature and media flow would therefore be a valuable tool for long term imaging experiments. Rapid prototyping using 3D printing is particularly suitable as a production method as it offers high flexibility in design, is widely available and allows a high degree of customizing. We study neural regeneration in zebrafish. Regeneration is limited in humans, but zebrafish recover from neural damage within days. Yet, the underlying regenerative mechanisms remain unclear. We developed an agarose based mounting system that holds the embryos in defined positions along removable strips. Homeostasis and temperature control is ensured by channels circulating buffer and heated water. This allows to image up to 120 larvae simultaneously for more than two days. Its flexibility and the low-volume, high larvae ratio will allow screening of small compound libraries. Taken together, we offer a low cost, highly adaptable solution for long term in-vivo imaging.

A 3D paper-based enzymatic fuel cell for self-powered, low-cost glucose monitoring.

Science.gov (United States)

Fischer, Christopher; Fraiwan, Arwa; Choi, Seokheun

2016-05-15

In this work, we demonstrate a novel low-cost, self-powered paper-based biosensor for glucose monitoring. The device operating mechanism is based on a glucose/oxygen enzymatic fuel cell using an electrochemical energy conversion as a transducing element for glucose monitoring. The self-powered glucose biosensor features (i) a 3D origami paper-based structure for easy system integration onto paper, (ii) an air-cathode on paper for low-cost production and easy operation, and (iii) a screen printed chitosan/glucose oxidase anode for stable current generation as an analytical signal for glucose monitoring. The sensor showed a linear range of output current at 1-5mM glucose (R(2)=0.996) with a sensitivity of 0.02 µA mM(-1). The advantages offered by such a device, including a low cost, lack of external power sources/sophisticated external transducers, and the capacity to rapidly generate reliable results, are well suited for the clinical and social settings of the developing world. Copyright © 2015 Elsevier B.V. All rights reserved.

Subsystem cost data for the tritium systems test assembly

International Nuclear Information System (INIS)

Bartlit, J.R.; Anderson, J.L.; Rexroth, V.G.

1983-01-01

Details of subsystem costs are among the questions most frequently asked about the $14.4 million Tritium Systems Test Assembly (TSTA) at Los Alamos National Laboratory. This paper presents a breakdown of cost components for each of the 20 major subsystems of TSTA. Also included are details to aid in adjusting the costs to other years, contracting conditions, or system sizes

Strategies to fight low-cost rivals.

Science.gov (United States)

Kumar, Nirmalya

2006-12-01

Companies find it challenging and yet strangely reassuring to take on opponents whose strategies, strengths, and weaknesses resemble their own. Their obsession with familiar rivals, however, has blinded them to threats from disruptive, low-cost competitors. Successful price warriors, such as the German retailer Aldi, are changing the nature of competition by employing several tactics: focusing on just one or a few consumer segments, delivering the basic product or providing one benefit better than rivals do, and backing low prices with superefficient operations. Ignoring cutprice rivals is a mistake because they eventually force companies to vacate entire market segments. Price wars are not the answer, either: Slashing prices usually lowers profits for incumbents without driving the low-cost entrants out of business. Companies take various approaches to competing against cut-price players. Some differentiate their products--a strategy that works only in certain circumstances. Others launch low-cost businesses of their own, as many airlines did in the 1990s--a so-called dual strategy that succeeds only if companies can generate synergies between the existing businesses and the new ventures, as the financial service providers HSBC and ING did. Without synergies, corporations are better off trying to transform themselves into low-cost players, a difficult feat that Ryanair accomplished in the 1990s, or into solution providers. There will always be room for both low-cost and value-added players. How much room each will have depends not only on the industry and customers' preferences, but also on the strategies traditional businesses deploy.

A Novel Low-Cost Sensor Prototype for Monitoring Temperature during Wine Fermentation in Tanks

Directory of Open Access Journals (Sweden)

Carlos de Castro

2013-02-01

Full Text Available This paper presents a multipurpose and low cost sensor for temperature control over the wine fermentation process, in order to steadily communicate data through wireless modules in real time to a viticulturist’s mobile or fixed device. The advantage of our prototype is due to the fact that it will be used by small winemakers in the “Ribera del Duero” area, and as it is a cheaper sensor and easy to use for the control and monitoring of the grape fermentation process, it will probably be used by other business men with the same necessities in the region. The microcontroller MSP430G2553 is among the components that make up the sensor, that are integrated onto a motherboard. It communicates with the RN-42 Bluetooth module through an UART interface. After verifying that all elements are working correctly, the parts are assembled to form the final prototype. This device has been tested in a winery in the region, fulfilling the initial project specifications.

Low-cost uncooled VOx infrared camera development

Science.gov (United States)

Li, Chuan; Han, C. J.; Skidmore, George D.; Cook, Grady; Kubala, Kenny; Bates, Robert; Temple, Dorota; Lannon, John; Hilton, Allan; Glukh, Konstantin; Hardy, Busbee

2013-06-01

The DRS Tamarisk® 320 camera, introduced in 2011, is a low cost commercial camera based on the 17 µm pixel pitch 320×240 VOx microbolometer technology. A higher resolution 17 µm pixel pitch 640×480 Tamarisk®640 has also been developed and is now in production serving the commercial markets. Recently, under the DARPA sponsored Low Cost Thermal Imager-Manufacturing (LCTI-M) program and internal project, DRS is leading a team of industrial experts from FiveFocal, RTI International and MEMSCAP to develop a small form factor uncooled infrared camera for the military and commercial markets. The objective of the DARPA LCTI-M program is to develop a low SWaP camera (costs less than US $500 based on a 10,000 units per month production rate. To meet this challenge, DRS is developing several innovative technologies including a small pixel pitch 640×512 VOx uncooled detector, an advanced digital ROIC and low power miniature camera electronics. In addition, DRS and its partners are developing innovative manufacturing processes to reduce production cycle time and costs including wafer scale optic and vacuum packaging manufacturing and a 3-dimensional integrated camera assembly. This paper provides an overview of the DRS Tamarisk® project and LCTI-M related uncooled technology development activities. Highlights of recent progress and challenges will also be discussed. It should be noted that BAE Systems and Raytheon Vision Systems are also participants of the DARPA LCTI-M program.

Low Cost Electrode Assembly for EEG Recordings in Mice

Directory of Open Access Journals (Sweden)

Emily C. Vogler

2017-11-01

Full Text Available Wireless electroencephalography (EEG of small animal subjects typically utilizes miniaturized EEG devices which require a robust recording and electrode assembly that remains in place while also being well-tolerated by the animal so as not to impair the ability of the animal to perform normal living activities or experimental tasks. We developed simple and fast electrode assembly and method of electrode implantation using electrode wires and wire-wrap technology that provides both higher survival and success rates in obtaining recordings from the electrodes than methods using screws as electrodes. The new wire method results in a 51% improvement in the number of electrodes that successfully record EEG signal. Also, the electrode assembly remains affixed and provides EEG signal for at least a month after implantation. Screws often serve as recording electrodes, which require either drilling holes into the skull to insert screws or affixing screws to the surface of the skull with adhesive. Drilling holes large enough to insert screws can be invasive and damaging to brain tissue, using adhesives may interfere with conductance and result in a poor signal, and soldering screws to wire leads results in fragile connections. The methods presented in this article provide a robust implant that is minimally invasive and has a significantly higher success rate of electrode implantation. In addition, the implant remains affixed and produces good recordings for over a month, while using economical, easily obtained materials and skills readily available in most animal research laboratories.

Low cost anti-soiling coatings for CSP collector mirrors and heliostats

Energy Technology Data Exchange (ETDEWEB)

Smith, Barton Barton [ORNL; Polyzos, Georgios [ORNL; Schaeffer, Daniel A [ORNL; Lee, Dominic F [ORNL; Datskos, Panos G [ORNL

2014-01-01

Most concentrating solar power (CSP) facilities in the USA are located in the desert southwest of the country where land and sunshine are abundant. But one of the significant maintenance problems and cost associated with operating CSP facilities in this region is the accumulation of dust, sand and other pollutants on the collector mirrors and heliostats. In this paper we describe the development of low cost, easy to apply anti-soiling coatings based on superhydrophobic (SH) functionalized nano silica materials and polymer binders that posses the key requirements necessary to inhibit particulate deposition on and sticking to CSP mirror surfaces, and thereby significantly reducing mirror cleaning costs and facility downtime.

A simple automated system for appetitive conditioning of zebrafish in their home tanks.

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Doyle, Jillian M; Merovitch, Neil; Wyeth, Russell C; Stoyek, Matthew R; Schmidt, Michael; Wilfart, Florentin; Fine, Alan; Croll, Roger P

2017-01-15

We describe here an automated apparatus that permits rapid conditioning paradigms for zebrafish. Arduino microprocessors were used to control the delivery of auditory or visual stimuli to groups of adult or juvenile zebrafish in their home tanks in a conventional zebrafish facility. An automatic feeder dispensed precise amounts of food immediately after the conditioned stimuli, or at variable delays for controls. Responses were recorded using inexpensive cameras, with the video sequences analysed with ImageJ or Matlab. Fish showed significant conditioned responses in as few as 5 trials, learning that the conditioned stimulus was a predictor of food presentation at the water surface and at the end of the tank where the food was dispensed. Memories of these conditioned associations persisted for at least 2days after training when fish were tested either as groups or as individuals. Control fish, for which the auditory or visual stimuli were specifically unpaired with food, showed no comparable responses. This simple, low-cost, automated system permits scalable conditioning of zebrafish with minimal human intervention, greatly reducing both variability and labour-intensiveness. It will be useful for studies of the neural basis of learning and memory, and for high-throughput screening of compounds modifying those processes. Copyright © 2016 Elsevier B.V. All rights reserved.

Automated processing of zebrafish imaging data: a survey.

Science.gov (United States)

Mikut, Ralf; Dickmeis, Thomas; Driever, Wolfgang; Geurts, Pierre; Hamprecht, Fred A; Kausler, Bernhard X; Ledesma-Carbayo, María J; Marée, Raphaël; Mikula, Karol; Pantazis, Periklis; Ronneberger, Olaf; Santos, Andres; Stotzka, Rainer; Strähle, Uwe; Peyriéras, Nadine

2013-09-01

Due to the relative transparency of its embryos and larvae, the zebrafish is an ideal model organism for bioimaging approaches in vertebrates. Novel microscope technologies allow the imaging of developmental processes in unprecedented detail, and they enable the use of complex image-based read-outs for high-throughput/high-content screening. Such applications can easily generate Terabytes of image data, the handling and analysis of which becomes a major bottleneck in extracting the targeted information. Here, we describe the current state of the art in computational image analysis in the zebrafish system. We discuss the challenges encountered when handling high-content image data, especially with regard to data quality, annotation, and storage. We survey methods for preprocessing image data for further analysis, and describe selected examples of automated image analysis, including the tracking of cells during embryogenesis, heartbeat detection, identification of dead embryos, recognition of tissues and anatomical landmarks, and quantification of behavioral patterns of adult fish. We review recent examples for applications using such methods, such as the comprehensive analysis of cell lineages during early development, the generation of a three-dimensional brain atlas of zebrafish larvae, and high-throughput drug screens based on movement patterns. Finally, we identify future challenges for the zebrafish image analysis community, notably those concerning the compatibility of algorithms and data formats for the assembly of modular analysis pipelines.

Automated Processing of Zebrafish Imaging Data: A Survey

Science.gov (United States)

Dickmeis, Thomas; Driever, Wolfgang; Geurts, Pierre; Hamprecht, Fred A.; Kausler, Bernhard X.; Ledesma-Carbayo, María J.; Marée, Raphaël; Mikula, Karol; Pantazis, Periklis; Ronneberger, Olaf; Santos, Andres; Stotzka, Rainer; Strähle, Uwe; Peyriéras, Nadine

2013-01-01

Abstract Due to the relative transparency of its embryos and larvae, the zebrafish is an ideal model organism for bioimaging approaches in vertebrates. Novel microscope technologies allow the imaging of developmental processes in unprecedented detail, and they enable the use of complex image-based read-outs for high-throughput/high-content screening. Such applications can easily generate Terabytes of image data, the handling and analysis of which becomes a major bottleneck in extracting the targeted information. Here, we describe the current state of the art in computational image analysis in the zebrafish system. We discuss the challenges encountered when handling high-content image data, especially with regard to data quality, annotation, and storage. We survey methods for preprocessing image data for further analysis, and describe selected examples of automated image analysis, including the tracking of cells during embryogenesis, heartbeat detection, identification of dead embryos, recognition of tissues and anatomical landmarks, and quantification of behavioral patterns of adult fish. We review recent examples for applications using such methods, such as the comprehensive analysis of cell lineages during early development, the generation of a three-dimensional brain atlas of zebrafish larvae, and high-throughput drug screens based on movement patterns. Finally, we identify future challenges for the zebrafish image analysis community, notably those concerning the compatibility of algorithms and data formats for the assembly of modular analysis pipelines. PMID:23758125

Object recognition memory in zebrafish.

Science.gov (United States)

May, Zacnicte; Morrill, Adam; Holcombe, Adam; Johnston, Travis; Gallup, Joshua; Fouad, Karim; Schalomon, Melike; Hamilton, Trevor James

2016-01-01

The novel object recognition, or novel-object preference (NOP) test is employed to assess recognition memory in a variety of organisms. The subject is exposed to two identical objects, then after a delay, it is placed back in the original environment containing one of the original objects and a novel object. If the subject spends more time exploring one object, this can be interpreted as memory retention. To date, this test has not been fully explored in zebrafish (Danio rerio). Zebrafish possess recognition memory for simple 2- and 3-dimensional geometrical shapes, yet it is unknown if this translates to complex 3-dimensional objects. In this study we evaluated recognition memory in zebrafish using complex objects of different sizes. Contrary to rodents, zebrafish preferentially explored familiar over novel objects. Familiarity preference disappeared after delays of 5 mins. Leopard danios, another strain of D. rerio, also preferred the familiar object after a 1 min delay. Object preference could be re-established in zebra danios by administration of nicotine tartrate salt (50mg/L) prior to stimuli presentation, suggesting a memory-enhancing effect of nicotine. Additionally, exploration biases were present only when the objects were of intermediate size (2 × 5 cm). Our results demonstrate zebra and leopard danios have recognition memory, and that low nicotine doses can improve this memory type in zebra danios. However, exploration biases, from which memory is inferred, depend on object size. These findings suggest zebrafish ecology might influence object preference, as zebrafish neophobia could reflect natural anti-predatory behaviour. Copyright © 2015 Elsevier B.V. All rights reserved.

A low-cost technique to manufacture a container to process meiofauna for scanning electron microscopy.

Science.gov (United States)

Abolafia, J

2015-09-01

An easy and low-cost method to elaborate a container to dehydrate nematodes and other meiofauna in order to process them for scanning electron microscopy (SEM) is presented. Illustrations of its elaboration, step by step, are included. In addition, a brief methodology to process meiofauna, especially nematodes and kinorhynchs, and illustrations are provided. With this methodology it is possible to easily introduce the specimens, to lock them in a closed chamber allowing the infiltration of fluids and gases (ethanol, acetone, carbon dioxide) but avoiding losing the specimens. After using this meiofauna basket for SEM the results are efficient. Examples of nematode and kinorhynch SEM pictures obtained using this methodology are also included. © 2015 Wiley Periodicals, Inc.

Scalable Light Module for Low-Cost, High-Efficiency Light- Emitting Diode Luminaires

Energy Technology Data Exchange (ETDEWEB)

Tarsa, Eric [Cree, Inc., Goleta, CA (United States)

2015-08-31

During this two-year program Cree developed a scalable, modular optical architecture for low-cost, high-efficacy light emitting diode (LED) luminaires. Stated simply, the goal of this architecture was to efficiently and cost-effectively convey light from LEDs (point sources) to broad luminaire surfaces (area sources). By simultaneously developing warm-white LED components and low-cost, scalable optical elements, a high system optical efficiency resulted. To meet program goals, Cree evaluated novel approaches to improve LED component efficacy at high color quality while not sacrificing LED optical efficiency relative to conventional packages. Meanwhile, efficiently coupling light from LEDs into modular optical elements, followed by optimally distributing and extracting this light, were challenges that were addressed via novel optical design coupled with frequent experimental evaluations. Minimizing luminaire bill of materials and assembly costs were two guiding principles for all design work, in the effort to achieve luminaires with significantly lower normalized cost ($/klm) than existing LED fixtures. Chief project accomplishments included the achievement of >150 lm/W warm-white LEDs having primary optics compatible with low-cost modular optical elements. In addition, a prototype Light Module optical efficiency of over 90% was measured, demonstrating the potential of this scalable architecture for ultra-high-efficacy LED luminaires. Since the project ended, Cree has continued to evaluate optical element fabrication and assembly methods in an effort to rapidly transfer this scalable, cost-effective technology to Cree production development groups. The Light Module concept is likely to make a strong contribution to the development of new cost-effective, high-efficacy luminaries, thereby accelerating widespread adoption of energy-saving SSL in the U.S.

Offset Printing Plate Quality Sensor on a Low-Cost Processor

Directory of Open Access Journals (Sweden)

Francisco Tirado

2013-10-01

Full Text Available The aim of this work is to develop a microprocessor-based sensor that measures the quality of the offset printing plate through the introduction of different image analysis applications. The main features of the presented system are the low cost, the low amount of power consumption, its modularity and easy integration with other industrial modules for printing plates, and its robustness against noise environments. For the sake of clarity, a viability analysis of previous software is presented through different strategies, based on dynamic histogram and Hough transform. This paper provides performance and scalability data compared with existing costly commercial devices. Furthermore, a general overview of quality control possibilities for printing plates is presented and could be useful to a system where such controls are regularly conducted.

Analysis of the thermal performance of a low-cost solar heating system; Analise do desempenho termico de um sistema de aquecimento solar de baixo custo

Energy Technology Data Exchange (ETDEWEB)

Lopo, Alexandre Boleira

2010-02-15

A solar collector to be used in a system for heating water for bathing, whose main characteristics are low cost and easy manufacturing and assembly is presented. The system operates under natural convection or thermosyphon. The absorbing surface of the collector is formed by twelve PVC pipes of 25 mm outside diameter connected in parallel via connections in T of the same material. The tubes were covered with absorbing fins made by recycled aluminum cans. We studied eight settings between absorber plate, thermal insulating EPS boards and thermal reservoirs 150 and 200 liters. It was determined the most efficient configuration for the correct purpose. We evaluated thermal parameters that proved the viability of the heating system studied (author)

Mitochondrial behavior during oogenesis in zebrafish: a confocal microscopy analysis.

Science.gov (United States)

Zhang, Yong-Zhong; Ouyang, Ying-Chun; Hou, Yi; Schatten, Heide; Chen, Da-Yuan; Sun, Qing-Yuan

2008-03-01

The behavior of mitochondria during early oogenesis remains largely unknown in zebrafish. We used three mitochondrial probes (Mito Tracker Red CMXRos, Mito Tracker Green FM, and JC-1) to stain early zebrafish oocyte mitochondria, and confocal microscopy to analyze mitochondrial aggregation and distribution. By using fluorescence recovery after photobleaching (FRAP), we traced mitochondrial movement. The microtubule assembly inhibitor nocodazole and microfilament inhibitor cytochalasin B (CB) were used to analyze the role of microtubules and microfilaments on mitochondrial movement. By using the dual emission probe, JC-1, and oxidative phosphorylation uncoupler, carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone (FCCP), we determined the distribution of active and inactive (low-active) mitochondria. Green/red fluorescence ratios of different sublocations in different oocyte groups stained by JC-1 were detected in merged (green and red) images. Our results showed that mitochondria exhibited a unique distribution pattern in early zebrafish oocytes. They tended to aggregate into large clusters in early stage I oocytes, but in a threadlike state in latter stage I oocytes. We detected a lower density mitochondrial area and a higher density mitochondrial area on opposite sides of the germinal vesicle. The green/red fluorescence ratios in different sublocations in normal oocytes were about 1:1. This implies that active mitochondria were distributed in all sublocations. FCCP treatment caused significant increases in the ratios. CB and nocodazole treatment caused an increase of the ratios in clusters and mitochondrial cloud, but not in dispersed areas. Mitochondria in different sublocations underwent fast dynamic movement. Inhibition or disruption of microtubules or microfilaments resulted in even faster mitochondrial free movement.

Integrating sequencing technologies in personal genomics: optimal low cost reconstruction of structural variants.

Directory of Open Access Journals (Sweden)

Jiang Du

2009-07-01

Full Text Available The goal of human genome re-sequencing is obtaining an accurate assembly of an individual's genome. Recently, there has been great excitement in the development of many technologies for this (e.g. medium and short read sequencing from companies such as 454 and SOLiD, and high-density oligo-arrays from Affymetrix and NimbelGen, with even more expected to appear. The costs and sensitivities of these technologies differ considerably from each other. As an important goal of personal genomics is to reduce the cost of re-sequencing to an affordable point, it is worthwhile to consider optimally integrating technologies. Here, we build a simulation toolbox that will help us optimally combine different technologies for genome re-sequencing, especially in reconstructing large structural variants (SVs. SV reconstruction is considered the most challenging step in human genome re-sequencing. (It is sometimes even harder than de novo assembly of small genomes because of the duplications and repetitive sequences in the human genome. To this end, we formulate canonical problems that are representative of issues in reconstruction and are of small enough scale to be computationally tractable and simulatable. Using semi-realistic simulations, we show how we can combine different technologies to optimally solve the assembly at low cost. With mapability maps, our simulations efficiently handle the inhomogeneous repeat-containing structure of the human genome and the computational complexity of practical assembly algorithms. They quantitatively show how combining different read lengths is more cost-effective than using one length, how an optimal mixed sequencing strategy for reconstructing large novel SVs usually also gives accurate detection of SNPs/indels, how paired-end reads can improve reconstruction efficiency, and how adding in arrays is more efficient than just sequencing for disentangling some complex SVs. Our strategy should facilitate the sequencing of

Small molecule screening platform for assessment of cardiovascular toxicity on adult zebrafish heart

Directory of Open Access Journals (Sweden)

Kitambi Satish

2012-03-01

Full Text Available Abstract Background Cardiovascular toxicity is a major limiting factor in drug development and requires multiple cost-effective models to perform toxicological evaluation. Zebrafish is an excellent model for many developmental, toxicological and regenerative studies. Using approaches like morpholino knockdown and electrocardiogram, researchers have demonstrated physiological and functional similarities between zebrafish heart and human heart. The close resemblance of the genetic cascade governing heart development in zebrafish to that of humans has propelled the zebrafish system as a cost-effective model to conduct various genetic and pharmacological screens on developing embryos and larvae. The current report describes a methodology for rapid isolation of adult zebrafish heart, maintenance ex vivo, and a setup to perform quick small molecule throughput screening, including an in-house implemented analysis script. Results Adult zebrafish were anesthetized and after rapid decapitation the hearts were isolated. The short time required for isolation of hearts allows dissection of multiple fishes, thereby obtaining a large sample size. The simple protocol for ex vivo culture allowed maintaining the beating heart for several days. The in-house developed script and spectral analyses allowed the readouts to be presented either in time domain or in frequency domain. Taken together, the current report offers an efficient platform for performing cardiac drug testing and pharmacological screens. Conclusion The new methodology presents a fast, cost-effective, sensitive and reliable method for performing small molecule screening. The variety of readouts that can be obtained along with the in-house developed analyses script offers a powerful setup for performing cardiac toxicity evaluation by researchers from both academics and industry.

On the feasibility to integrate low-cost MEMS accelerometers and GNSS receivers

Science.gov (United States)

Benedetti, Elisa; Dermanis, Athanasios; Crespi, Mattia

2017-06-01

The aim of this research was to investigate the feasibility of merging the benefits offered by low-cost GNSS and MEMS accelerometers technology, in order to promote the diffusion of low-cost monitoring solutions. A merging approach was set up at the level of the combination of kinematic results (velocities and displacements) coming from the two kinds of sensors, whose observations were separately processed, following to the so called loose integration, which sounds much more simple and flexible thinking about the possibility of an easy change of the combined sensors. At first, the issues related to the difference in reference systems, time systems and measurement rate and epochs for the two sensors were faced with. An approach was designed and tested to transform into unique reference and time systems the outcomes from GPS and MEMS and to interpolate the usually (much) more dense MEMS observation to common (GPS) epochs. The proposed approach was limited to time-independent (constant) orientation of the MEMS reference system with respect to the GPS one. Then, a data fusion approach based on the use of Discrete Fourier Transform and cubic splines interpolation was proposed both for velocities and displacements: MEMS and GPS derived solutions are firstly separated by a rectangular filter in spectral domain, and secondly back-transformed and combined through a cubic spline interpolation. Accuracies around 5 mm for slow and fast displacements and better than 2 mm/s for velocities were assessed. The obtained solution paves the way to a powerful and appealing use of low-cost single frequency GNSS receivers and MEMS accelerometers for structural and ground monitoring applications. Some additional remarks and prospects for future investigations complete the paper.

An easy-to-build, low-budget point-of-care ultrasound simulator: from Linux to a web-based solution.

Science.gov (United States)

Damjanovic, Domagoj; Goebel, Ulrich; Fischer, Benedikt; Huth, Martin; Breger, Hartmut; Buerkle, Hartmut; Schmutz, Axel

2017-12-01

Hands-on training in point-of-care ultrasound (POC-US) should ideally comprise bedside teaching, as well as simulated clinical scenarios. High-fidelity phantoms and portable ultrasound simulation systems are commercially available, however, at considerable costs. This limits their suitability for medical schools. A Linux-based software for Emergency Department Ultrasound Simulation (edus2TM) was developed by Kulyk and Olszynski in 2011. Its feasibility for POC-US education has been well-documented, and shows good acceptance. An important limitation to an even more widespread use of edus2, however, may be due to the need for a virtual machine for WINDOWS ® systems. Our aim was to adapt the original software toward an HTML-based solution, thus making it affordable and applicable in any simulation setting. We created an HTML browser-based ultrasound simulation application, which reads the input of different sensors, triggering an ultrasound video to be displayed on a respective device. RFID tags, NFC tags, and QR Codes™ have been integrated into training phantoms or were attached to standardized patients. The RFID antenna was hidden in a mock ultrasound probe. The application is independent from the respective device. Our application was used successfully with different trigger/scanner combinations and mounted readily into simulated training scenarios. The application runs independently from operating systems or electronic devices. This low-cost, browser-based ultrasound simulator is easy-to-build, very adaptive, and independent from operating systems. It has the potential to facilitate POC-US training throughout the world, especially in resource-limited areas.

Evaluating human cancer cell metastasis in zebrafish

International Nuclear Information System (INIS)

Teng, Yong; Xie, Xiayang; Walker, Steven; White, David T; Mumm, Jeff S; Cowell, John K

2013-01-01

In vivo metastasis assays have traditionally been performed in mice, but the process is inefficient and costly. However, since zebrafish do not develop an adaptive immune system until 14 days post-fertilization, human cancer cells can survive and metastasize when transplanted into zebrafish larvae. Despite isolated reports, there has been no systematic evaluation of the robustness of this system to date. Individual cell lines were stained with CM-Dil and injected into the perivitelline space of 2-day old zebrafish larvae. After 2-4 days fish were imaged using confocal microscopy and the number of metastatic cells was determined using Fiji software. To determine whether zebrafish can faithfully report metastatic potential in human cancer cells, we injected a series of cells with different metastatic potential into the perivitelline space of 2 day old embryos. Using cells from breast, prostate, colon and pancreas we demonstrated that the degree of cell metastasis in fish is proportional to their invasion potential in vitro. Highly metastatic cells such as MDA231, DU145, SW620 and ASPC-1 are seen in the vasculature and throughout the body of the fish after only 24–48 hours. Importantly, cells that are not invasive in vitro such as T47D, LNCaP and HT29 do not metastasize in fish. Inactivation of JAK1/2 in fibrosarcoma cells leads to loss of invasion in vitro and metastasis in vivo, and in zebrafish these cells show limited spread throughout the zebrafish body compared with the highly metastatic parental cells. Further, knockdown of WASF3 in DU145 cells which leads to loss of invasion in vitro and metastasis in vivo also results in suppression of metastasis in zebrafish. In a cancer progression model involving normal MCF10A breast epithelial cells, the degree of invasion/metastasis in vitro and in mice is mirrored in zebrafish. Using a modified version of Fiji software, it is possible to quantify individual metastatic cells in the transparent larvae to correlate with

Triclosan Lacks (Anti-Estrogenic Effects in Zebrafish Cells but Modulates Estrogen Response in Zebrafish Embryos

Directory of Open Access Journals (Sweden)

Hélène Serra

2018-04-01

Full Text Available Triclosan (TCS, an antimicrobial agent widely found in the aquatic environment, is suspected to act as an endocrine disrupting compound, however mechanistic information is lacking in regards to aquatic species. This study assessed the ability of TCS to interfere with estrogen receptor (ER transcriptional activity, in zebrafish-specific in vitro and in vivo reporter gene assays. We report that TCS exhibits a lack of either agonistic or antagonistic effects on a panel of ER-expressing zebrafish (ZELH-zfERα and -zfERβ and human (MELN cell lines. At the organism level, TCS at concentrations of up to 0.3 µM had no effect on ER-regulated brain aromatase gene expression in transgenic cyp19a1b-GFP zebrafish embryos. At a concentration of 1 µM, TCS interfered with the E2 response in an ambivalent manner by potentializing a low E2 response (0.625 nM, but decreasing a high E2 response (10 nM. Altogether, our study suggests that while modulation of ER-regulated genes by TCS may occur in zebrafish, it does so irrespective of a direct binding and activation of zfERs.

Non-invasive electrocardiogram detection of in vivo zebrafish embryos using electric potential sensors

Science.gov (United States)

Rendon-Morales, E.; Prance, R. J.; Prance, H.; Aviles-Espinosa, R.

2015-11-01

In this letter, we report the continuous detection of the cardiac electrical activity in embryonic zebrafish using a non-invasive approach. We present a portable and cost-effective platform based on the electric potential sensing technology, to monitor in vivo electrocardiogram activity from the zebrafish heart. This proof of principle demonstration shows how electrocardiogram measurements from the embryonic zebrafish may become accessible by using electric field detection. We present preliminary results using the prototype, which enables the acquisition of electrophysiological signals from in vivo 3 and 5 days-post-fertilization zebrafish embryos. The recorded waveforms show electrocardiogram traces including detailed features such as QRS complex, P and T waves.

Comparative analysis of the transcriptome responses of zebrafish embryos after exposure to low concentrations of cadmium, cobalt and copper.

Science.gov (United States)

Sonnack, Laura; Klawonn, Thorsten; Kriehuber, Ralf; Hollert, Henner; Schäfers, Christoph; Fenske, Martina

2018-03-01

Metal toxicity is a global environmental challenge. Fish are particularly prone to metal exposure, which can be lethal or cause sublethal physiological impairments. The objective of this study was to investigate how adverse effects of chronic exposure to non-toxic levels of essential and non-essential metals in early life stage zebrafish may be explained by changes in the transcriptome. We therefore studied the effects of three different metals at low concentrations in zebrafish embryos by transcriptomics analysis. The study design compared exposure effects caused by different metals at different developmental stages (pre-hatch and post-hatch). Wild-type embryos were exposed to solutions of low concentrations of copper (CuSO 4 ), cadmium (CdCl 2 ) and cobalt (CoSO 4 ) until 96h post-fertilization (hpf) and microarray experiments were carried out to determine transcriptome profiles at 48 and 96hpf. We found that the toxic metal cadmium affected the expression of more genes at 96hpf than 48hpf. The opposite effect was observed for the essential metals cobalt and copper, which also showed enrichment of different GO terms. Genes involved in neuromast and motor neuron development were significantly enriched, agreeing with our previous results showing motor neuron and neuromast damage in the embryos. Our data provide evidence that the response of the transcriptome of fish embryos to metal exposure differs for essential and non-essential metals. Copyright © 2017 Elsevier Inc. All rights reserved.

Comparison of the Exomes of Common Carp (Cyprinus carpio) and Zebrafish (Danio rerio)

Science.gov (United States)

Henkel, Christiaan V.; Dirks, Ron P.; Jansen, Hans J.; Forlenza, Maria; Wiegertjes, Geert F.; Howe, Kerstin; van den Thillart, Guido E.E.J.M.

2012-01-01

Abstract Research on common carp, Cyprinus carpio, is beneficial for zebrafish research because of resources available owing to its large body size, such as the availability of sufficient organ material for transcriptomics, proteomics, and metabolomics. Here we describe the shot gun sequencing of a clonal double-haploid common carp line. The assembly consists of 511891 scaffolds with an N50 of 17 kb, predicting a total genome size of 1.4–1.5 Gb. A detailed analysis of the ten largest scaffolds indicates that the carp genome has a considerably lower repeat coverage than zebrafish, whilst the average intron size is significantly smaller, making it comparable to the fugu genome. The quality of the scaffolding was confirmed by comparisons with RNA deep sequencing data sets and a manual analysis for synteny with the zebrafish, especially the Hox gene clusters. In the ten largest scaffolds analyzed, the synteny of genes is almost complete. Comparisons of predicted exons of common carp with those of the zebrafish revealed only few genes specific for either zebrafish or carp, most of these being of unknown function. This supports the hypothesis of an additional genome duplication event in the carp evolutionary history, which—due to a higher degree of compactness—did not result in a genome larger than that of zebrafish. PMID:22715948

PEM fuel cell cost minimization using ``Design For Manufacture and Assembly`` techniques

Energy Technology Data Exchange (ETDEWEB)

Lomax, F.D. Jr.; James, B.D. [Directed Technologies, Inc., Arlington, VA (United States); Mooradian, R.P. [Ford Motor Co., Dearborn, MI (United States)

1997-12-31

Polymer Electrolyte Membrane (PEM) fuel cells fueled with direct hydrogen have demonstrated substantial technical potential to replace Internal Combustion Engines (ICE`s) in light duty vehicles. Such a transition to a hydrogen economy offers the potential of substantial benefits from reduced criteria and greenhouse emissions as well as reduced foreign fuel dependence. Research conducted for the Ford Motor Co. under a US Department of Energy contract suggests that hydrogen fuel, when used in a fuel cell vehicle (FCV), can achieve a cost per vehicle mile less than or equal to the gasoline cost per mile when used in an ICE vehicle. However, fuel cost parity is not sufficient to ensure overall economic success: the PEM fuel cell power system itself must be of comparable cost to the ICE. To ascertain if low cost production of PEM fuel cells is feasible, a powerful set of mechanical engineering tools collectively referred to as Design for Manufacture and Assembly (DFMA) has been applied to several representative PEM fuel cell designs. The preliminary results of this work are encouraging, as presented.

A low-cost, modular, microwave-linked, color TV inspection system

International Nuclear Information System (INIS)

Panda, N.C.

1991-01-01

This paper reports that many custom-built radiation-shielded CCTV inspection systems for nuclear facilities are available in the market. This author, however, could find no reference to units using low-cost nodular technology for wireless transmission and control of color CCTV signals in radiation environments. The system that was developed is a process control observation tool geared toward identifying locations ad volumes of accumulated in-cell solids. It also performs remote integrity assessments of tanks and pipe routings that are required by regulatory agencies. System highlights are: microwave transmission of video and control signals, low cost, low maintenance, and modular design. Use of standard components enables easy exchange of modules. Microwave transmission resolved the complications of a wired system while increasing reliability and safety. The video image is created by the remote in-cell color TV camera and transmitted by microwave out of the cell to TV monitors at consoles in non-radiation zones

A low cost PSD-based monocular motion capture system

Science.gov (United States)

Ryu, Young Kee; Oh, Choonsuk

2007-10-01

This paper describes a monocular PSD-based motion capture sensor to employ with commercial video game systems such as Microsoft's XBOX and Sony's Playstation II. The system is compact, low-cost, and only requires a one-time calibration at the factory. The system includes a PSD(Position Sensitive Detector) and active infrared (IR) LED markers that are placed on the object to be tracked. The PSD sensor is placed in the focal plane of a wide-angle lens. The micro-controller calculates the 3D position of the markers using only the measured intensity and the 2D position on the PSD. A series of experiments were performed to evaluate the performance of our prototype system. From the experimental results we see that the proposed system has the advantages of the compact size, the low cost, the easy installation, and the high frame rates to be suitable for high speed motion tracking in games.

Low-cost computer mouse for the elderly or disabled in Taiwan.

Science.gov (United States)

Chen, C-C; Chen, W-L; Chen, B-N; Shih, Y-Y; Lai, J-S; Chen, Y-L

2014-01-01

A mouse is an important communication interface between a human and a computer, but it is still difficult to use for the elderly or disabled. To develop a low-cost computer mouse auxiliary tool. The principal structure of the low-cost mouse auxiliary tool is the IR (infrared ray) array module and the Wii icon sensor module, which combine with reflective tape and the SQL Server database. This has several benefits including cheap hardware cost, fluent control, prompt response, adaptive adjustment and portability. Also, it carries the game module with the function of training and evaluation; to the trainee, it is really helpful to upgrade the sensitivity of consciousness/sense and the centralization of attention. The intervention phase/maintenance phase, with regard to clicking accuracy and use of time, p value (p< 0.05) reach the level of significance. The development of the low cost adaptive computer mouse auxiliary tool was completed during the study and was also verified as having the characteristics of low cost, easy operation and the adaptability. To patients with physical disabilities, if they have independent control action parts of their limbs, the mouse auxiliary tool is suitable for them to use, i.e. the user only needs to paste the reflective tape by the independent control action parts of the body to operate the mouse auxiliary tool.

A participatory and integrative approach to increase productivity and comfort in assembly

NARCIS (Netherlands)

Looze, M.P. de; Rhijn, G. van; Tuinzaad, B.; Deursen, J. van

2000-01-01

Manufacturers of manually assembled products are more and more forced to improve the flow of assembly orders together with a more efficient employment, in order to meet increasing demands on short delivery times, high product variety, good quality and low manufacturing costs. At the same time, the

Low-cost evacuated-tube solar collector appendices. Final report

Energy Technology Data Exchange (ETDEWEB)

Beecher, D.T.

1980-05-31

A low cost solar heat energy collector module and array has been designed using the evacuated tube, selective absorber, air cooled concept. Glass tubing as used in fluorescent lamps with automatic sealing methods is a key feature of the evacuated tube design. A molded fiber glass concentrating reflector panel and sheet metal header assembly are proposed. Major design problems involved included the cost of materials and labor, thermal expansion and distortion problems, high stagnation and operating temperatures, isolation, thermal efficiency, sealing, joining, air pressure drop, and weight of the preassembled module. A cost of less than $5 per active square foot of collecting surface has been estimated for materials and labor of the module and its mounting frame.

Relationship between workload and low back pain in assembly line workers

Directory of Open Access Journals (Sweden)

Reza Kalantari

2016-06-01

Full Text Available Introduction: Work pressure and excessive workload can jeopardize and impair the people’s health. One of these impairments is musculoskeletal disorders. Among these disorders, low back pain is the most common and most costly problem. The purpose of this study was to investigate the relationship between workload and prevalence of low back pain in assembly line workers of a car manufacturing factory. Methods: This cross-sectional study was conducted on 69 workers working in the assembly line of a factory. Data collection tools included three questionnaires: demographic questionnaire, NASA Task Load Index (NASA-TLX and Cornell Musculoskeletal Discomfort Questionnaire (CMDQ. Data were analyzed by descriptive and inferential (T-test and One-way ANOVA statistics. Results: Of the workers, 72.5% were female. The average total workload was 71.42% and the prevalence of musculoskeletal disorders in low back was 43.37%. The results of the analysis of relationship between workload and the prevalence of low back pain showed a significant relationship between physical/ mental workload and the incidence of low back pain (P<0.05. Conclusion: The more is the workload on the person, the greater is the risk of low back pain. Measures such as increasing the number of workers to distribute the workload, slowing the work pace, having work-rest periods for workers, improving psychological conditions of work, etc. can be useful in this regard.

A low cost indoor localization system for mobile robot experimental setup

Science.gov (United States)

Adinandra, S.; Syarif, A.

2018-04-01

Indoor localization becomes one of the most important part in mobile robot system One fundamental requirement is to provide an easy-to-use and practical localization system for real-time experiments. In this paper we propose a combination of a recent open source virtual reality (VR) tools, a simple MATLAB code and a low cost USB webcam as an indoor mobile robot localization system Using the VR tools as a server and MATLAB as a client, the proposed solution can cover up to 1.6 [m] × 3.2 [m] with the measurement position accuracy up to 1.2 [cm]. The system is insensitive to light, easy to move and can be quickly set up. A series of successful real-time experiments with three different mobile robot types has been conducted.

A disposable and multifunctional capsule for easy operation of microfluidic elastomer systems

International Nuclear Information System (INIS)

Thorslund, Sara; Läräng, Thomas; Kreuger, Johan; Nguyen, Hugo; Barkefors, Irmeli

2011-01-01

The global lab-on-chip and microfluidic markets for cell-based assays have been predicted to grow considerably, as novel microfluidic systems enable cell biologists to perform in vitro experiments at an unprecedented level of experimental control. Nevertheless, microfluidic assays must, in order to compete with conventional assays, be made available at easily affordable costs, and in addition be made simple to operate for users having no previous experience with microfluidics. We have to this end developed a multifunctional microfluidic capsule that can be mass-produced at low cost in thermoplastic material. The capsule enables straightforward operation of elastomer inserts of optional design, here exemplified with insert designs for molecular gradient formation in microfluidic cell culture systems. The integrated macro–micro interface of the capsule ensures reliable connection of the elastomer fluidic structures to an external perfusion system. A separate compartment in the capsule filled with superabsorbent material is used for internal waste absorption. The capsule assembly process is made easy by integrated snap-fits, and samples within the closed capsule can be analyzed using both inverted and upright microscopes. Taken together, the capsule concept presented here could help accelerate the use of microfluidic-based biological assays in the life science sector. (technical note)

Precise Truss Assembly Using Commodity Parts and Low Precision Welding

Science.gov (United States)

Komendera, Erik; Reishus, Dustin; Dorsey, John T.; Doggett, W. R.; Correll, Nikolaus

2014-01-01

Hardware and software design and system integration for an intelligent precision jigging robot (IPJR), which allows high precision assembly using commodity parts and low-precision bonding, is described. Preliminary 2D experiments that are motivated by the problem of assembling space telescope optical benches and very large manipulators on orbit using inexpensive, stock hardware and low-precision welding are also described. An IPJR is a robot that acts as the precise "jigging", holding parts of a local structure assembly site in place, while an external low precision assembly agent cuts and welds members. The prototype presented in this paper allows an assembly agent (for this prototype, a human using only low precision tools), to assemble a 2D truss made of wooden dowels to a precision on the order of millimeters over a span on the order of meters. The analysis of the assembly error and the results of building a square structure and a ring structure are discussed. Options for future work, to extend the IPJR paradigm to building in 3D structures at micron precision are also summarized.

Low cost sic coated erosion resistant graphite

International Nuclear Information System (INIS)

Zafar, M.F.; Nicholls, J.R.

2007-01-01

The development of materials with unique and improved properties using low cost processes is essential to increase performance and reduce cost of the solid rocket motors. Specifically advancements are needed for boost phase nozzle. As these motors operate at very high pressure and temperatures, the nozzle must survive high thermal stresses with minimal erosion to maintain performance. Currently three material choices are being exploited; which are refractory metals, graphite and carbon-carbon composites. Of these three materials graphite is the most attractive choice because of its low cost, light weight, and easy forming. However graphite is prone to erosion, both chemical and mechanical, which may affect the ballistic conditions and mechanical properties of the nozzle. To minimize this erosion high density graphite is usually preferred; which is again very expensive. Another technique used to minimize the erosion is Pyrolytic Graphite (PG) coating inside the nozzle. However PG coating is prone to cracking and spallation along with very cumbersome deposition process. Another possible methodology to avoid this erosion is to convert the inside surface of the rocket nozzle to Silicon Carbide (SiC), which is very erosion resistant and have much better thermal stability compared to graphite and even PG. Due to its functionally gradient nature such a layer will be very adherent and resistant to spallation. The current research is focused on synthesizing, characterizing and oxidation testing of such a converted SiC layer on commercial grade graphite. (author)

A conceptual design of assembly strategy and dedicated tools for assembly of 40o sector

International Nuclear Information System (INIS)

Park, H.K.; Nam, K.O.; Kim, D.J.; Ahn, H.J.; Lee, J.H.; Im, K.; Shaw, R.

2010-01-01

The International Thermanuclear Experimental Reactor (ITER) tokamak device is composed of 9 vacuum vessel (VV)/toroidal field coils (TFCs)/vacuum vessel thermal shields (VVTS) 40 o sectors. Each VV/TFCs/VVTS 40 o sector is made up of one 40 o VV, two 20 o TFCs and associated VVTS segments. The 40 o sectors are sub-assembled at assembly hall respectively and then nine 40 o sectors sub-assembled at assembly hall are finally assembled at tokamak in-pit hall. The assembly strategy and tools for the 40 o sector sub-assembly and final assembly should be developed to satisfy the basic assembly requirements of the ITER tokamak device. Accordingly, the purpose-built assembly tools should be designed and manufactured considering assembly plan, available space, cost, safety, easy operation, efficient maintenance, and so on. The 40 o sector assembly tools are classified into 2 groups. One group is the sub-assembly tools including upending tool, lifting tool, sub-assembly tool, VV supports and bracing tools used at assembly hall and the other group is the in-pit assembly tools including lifting tool, central column, radial beams and their supports. This paper describes the current status of the assembly strategy and major tools for the VV/TFCs/VVTS 40 o sector assembly at in-pit hall and assembly hall. The conceptual design of the major assembly tools and assembly process at assembly hall and tokamak in-pit hall are presented also.

Zebrafish syntenic relationship to human/mouse genomes revealed by radiation hybrid mapping

International Nuclear Information System (INIS)

Samonte, Irene E.

2007-01-01

Zebrafish (Danio rerio) is an excellent model system for vertebrate developmental analysis and a new model for human disorders. In this study, however, zebrafish was used to determine its syntenic relationship to human/mouse genomes using the zebrafish-hamster radiation hybrid panel. The focus was on genes residing on chromosomes 6 and 17 of human and mouse, respectively, and some other genes of either immunologic or evolutionary importance. Gene sequences of interest and zebrafish expressed sequence tags deposited in the GenBank were used in identifying zebrafish homologs. Polymerase chain reaction (PCR) amplification, cloning and subcloning, sequencing, and phylogenetic analysis were done to confirm the homology of the candidate genes in zebrafish. The promising markers were then tested in the 94 zebrafish-hamster radiation hybrid panel cell lines and submitted for logarithm of the odds (LOD) score analysis to position genes on the zebrafish map. A total of 19 loci were successfully mapped to zebrafish linkage groups 1, 14, 15, 19, and 20. Four of these loci were positioned in linkage group 20, whereas, 3 more loci were added in linkage group 19, thus increasing to 34 loci the number of human genes syntenic to the group. With the sequencing of the zebrafish genome, about 20 more MHC genes were reported linked on the same group. (Author)

The titin A-band rod domain is dispensable for initial thick filament assembly in zebrafish.

Science.gov (United States)

Myhre, J Layne; Hills, Jordan A; Prill, Kendal; Wohlgemuth, Serene L; Pilgrim, David B

2014-03-01

The sarcomeres of skeletal and cardiac muscle are highly structured protein arrays, consisting of thick and thin filaments aligned precisely to one another and to their surrounding matrix. The contractile mechanisms of sarcomeres are generally well understood, but how the patterning of sarcomeres is initiated during early skeletal muscle and cardiac development remains uncertain. Two of the most widely accepted hypotheses for this process include the "molecular ruler" model, in which the massive protein titin defines the length of the sarcomere and provides a scaffold along which the myosin thick filament is assembled, and the "premyofibril" model, which proposes that thick filament formation does not require titin, but that a "premyofibril" consisting of non-muscle myosin, α-actinin and cytoskeletal actin is used as a template. Each model posits a different order of necessity of the various components, but these have been difficult to test in vivo. Zebrafish motility mutants with developmental defects in sarcomere patterning are useful for the elucidation of such mechanisms, and here we report the analysis of the herzschlag mutant, which shows deficits in both cardiac and skeletal muscle. The herzschlag mutant produces a truncated titin protein, lacking the C-terminal rod domain that is proposed to act as a thick filament scaffold, yet muscle patterning is still initiated, with grossly normal thick and thin filament assembly. Only after embryonic muscle contraction begins is breakdown of sarcomeric myosin patterning observed, consistent with the previously noted role of titin in maintaining the contractile integrity of mature sarcomeres. This conflicts with the "molecular ruler" model of early sarcomere patterning and supports a titin-independent model of thick filament organization during sarcomerogenesis. These findings are also consistent with the symptoms of human titin myopathies that exhibit a late onset, such as tibial muscular dystrophy. Copyright © 2013

Design of a birefringent Michelson interferometer-based interleaver with ultra-low dispersion and low cost.

Science.gov (United States)

Hu, Haocheng; Zheng, Baozhong; Liu, Qingming; Li, Yang; Wu, Li; Gu, Shijie

2011-11-21

We design and demonstrate a birefringent Michelson interferometer based interleaver with ultra-low dispersion and low cost. The interleaver consists of polarizing beam splitters (PBS's) and quarter-wave plates and half-wave plates. The PBS's based Michelson interferometers provide the optical path difference for interference between the two orthogonal polarization components and the half-wave plates provide the birefringent needed to minimize ripple of output. The designed interleaver with two-stage interferometer in a 50 GHz channel spacing application exhibits a 0.5 dB passband and a 25 dB stopband both 27 GHz; a channel isolation higher than 35 dB and chromatic dispersion less than ±5 ps/nm within 0.5 dB passband; 1.3 dB insertion loss and 0.3 dB PDL; 0.04 GHz/°C thermal stability. Since all of the optical components can be optically bonded together, the device is robust and easy to be aligned, which reduces labor cost. © 2011 Optical Society of America

Continual low-level MEK inhibition ameliorates cardio-facio-cutaneous phenotypes in zebrafish

Directory of Open Access Journals (Sweden)

Corina Anastasaki

2012-07-01

Cardio-facio-cutaneous (CFC syndrome is caused by germline mutations in KRAS, BRAF and MEK1/2. The highly selective and potent MEK inhibitors that have been developed as anti-cancer agents hold potential as therapeutics for CFC syndrome. We have previously shown that the effects of CFC mutations on zebrafish gastrulation can be prevented by a 1-hour treatment with MEK inhibitors within a specific developmental time-window. However, MEK activity is essential for normal development and PD0325901 treatment outside this treatment window leads to additional developmental defects in MEK-dependent tissues. We now test ten different doses of PD0325901 at six developmental time points and assess the effects on body axis length, heart development and craniofacial structures in zebrafish embryos. Notably, we find that a continuous low-level dose of PD0325901 that has only minor inhibition of MEK activity can prevent the action of both the common CFC BRAFQ257R kinase-active allele and the BRAFG596V kinase-impaired mutant allele through the first 5 days of development. These results provide a detailed study of the effects of PD0325901 in development and show that, unlike in cancer, which requires robust inhibition of MAPK signalling, a partial reduction in phospho-ERK1/2 activity is sufficient to moderate the developmental effects of BRAFCFC mutations.

High-Throughput Behavioral Screens: the First Step towards Finding Genes Involved in Vertebrate Brain Function Using Zebrafish

Directory of Open Access Journals (Sweden)

Robert Gerlai

2010-04-01

Full Text Available The zebrafish has been in the forefront of developmental biology for three decades and has become a favorite of geneticists. Due to the accumulated genetic knowledge and tools developed for the zebrafish it is gaining popularity in other disciplines, including neuroscience. The zebrafish offers a compromise between system complexity (it is a vertebrate similar in many ways to our own species and practical simplicity (it is small, easy to keep, and prolific. Such features make zebrafish an excellent choice for high throughput mutation and drug screening. For the identification of mutation or drug induced alteration of brain function arguably the best methods are behavioral test paradigms. This review does not present experimental examples for the identification of particular genes or drugs. Instead it describes how behavioral screening methods may enable one to find functional alterations in the vertebrate brain. Furthermore, the review is not comprehensive. The behavioral test examples presented are biased according to the personal interests of the author. They will cover research areas including learning and memory, fear and anxiety, and social behavior. Nevertheless, the general principles will apply to other functional domains and should represent a snapshot of the rapidly evolving behavioral screening field with zebrafish.

Cardiac Ca2+ signalling in zebrafish: Translation of findings to man.

Science.gov (United States)

van Opbergen, Chantal J M; van der Voorn, Stephanie M; Vos, Marc A; de Boer, Teun P; van Veen, Toon A B

2018-05-07

Sudden cardiac death is a leading cause of death worldwide, mainly caused by highly disturbed electrical activation patterns in the heart. Currently, murine models are the most popular model to study underlying molecular mechanisms of inherited or acquired cardiac electrical abnormalities, although the numerous electrophysiological discrepancies between mouse and human raise the question whether mice are the optimal model to study cardiac rhythm disorders. Recently it has been uncovered that the zebrafish cardiac electrophysiology seems surprisingly similar to the human heart, mainly because the zebrafish AP contains a clear plateau phase and ECG characteristics show alignment with the human ECG. Although, before using zebrafish as a model to study cardiac arrhythmogenesis, however, it is very important to gain a better insight into the electrophysiological characteristics of the zebrafish heart. In this review we outline the electrophysiological machinery of the zebrafish cardiomyocytes, with a special focus on the intracellular Ca 2+ dynamics and excitation-contraction coupling. We debate the potential of zebrafish as a model to study human cardiovascular diseases and postulate steps to employ zebrafish into a more 'humanized' model. Copyright © 2018 Elsevier Ltd. All rights reserved.

A demonstration of a low cost approach to security at shipping facilities and ports

Science.gov (United States)

Huck, Robert C.; Al Akkoumi, Mouhammad K.; Herath, Ruchira W.; Sluss, James J., Jr.; Radhakrishnan, Sridhar; Landers, Thomas L.

2010-04-01

Government funding for the security at shipping facilities and ports is limited so there is a need for low cost scalable security systems. With over 20 million sea, truck, and rail containers entering the United States every year, these facilities pose a large risk to security. Securing these facilities and monitoring the variety of traffic that enter and leave is a major task. To accomplish this, the authors have developed and fielded a low cost fully distributed building block approach to port security at the inland Port of Catoosa in Oklahoma. Based on prior work accomplished in the design and fielding of an intelligent transportation system in the United States, functional building blocks, (e.g. Network, Camera, Sensor, Display, and Operator Console blocks) can be assembled, mixed and matched, and scaled to provide a comprehensive security system. The following functions are demonstrated and scaled through analysis and demonstration: Barge tracking, credential checking, container inventory, vehicle tracking, and situational awareness. The concept behind this research is "any operator on any console can control any device at any time."

Operant models of relapse in zebrafish (Danio rerio): Resurgence, renewal, and reinstatement.

Science.gov (United States)

Kuroda, Toshikazu; Mizutani, Yuto; Cançado, Carlos R X; Podlesnik, Christopher A

2017-09-29

Zebrafish are a widely used animal model in biomedical research, as an alternative to mammals, for having features such as a fully sequenced genome, high fecundity, and low-cost maintenance, but behavioral research with these fish remains scarce. The present study investigated whether zebrafish could be a new animal model for studies on the relapse of behavior (e.g., addiction and overeating) after the behavior has been extinguished. Specifically, we examined whether zebrafish would show three different types of relapse commonly studied with other species: resurgence, renewal, and reinstatement. For resurgence, a target response (i.e., approaching a sensor) was established by presenting a reinforcer (i.e., shrimp eggs) contingent upon the response in Phase 1; the target response was extinguished while introducing reinforcement for an alternative response in Phase 2; neither response produced the reinforcer in Phase 3. For renewal, a target response was established under Context A in Phase 1 and was extinguished under Context B in Phase 2; the fish were placed back in Context A in Phase 3, where extinction remained in effect. For reinstatement, a target response was established in Phase 1 and was extinguished in Phase 2; the reinforcer was presented independently of responding in Phase 3. Each type of relapse occurred in Phase 3. These results replicate and extend previous findings on relapse to a new species and suggest that zebrafish can be a useful animal model for studying the interactions of biological and environmental factors that lead to relapse. Copyright © 2017 Elsevier B.V. All rights reserved.

Low Cost Upper Stage-Class Propulsion (LCUSP)

Science.gov (United States)

Vickers, John

2015-01-01

NASA is making space exploration more affordable and viable by developing and utilizing innovative manufacturing technologies. Technology development efforts at NASA in propulsion are committed to continuous innovation of design and manufacturing technologies for rocket engines in order to reduce the cost of NASA's journey to Mars. The Low Cost Upper Stage-Class Propulsion (LCUSP) effort will develop and utilize emerging Additive Manufacturing (AM) to significantly reduce the development time and cost for complex rocket propulsion hardware. Benefit of Additive Manufacturing (3-D Printing) Current rocket propulsion manufacturing techniques are costly and have lengthy development times. In order to fabricate rocket engines, numerous complex parts made of different materials are assembled in a way that allow the propellant to collect heat at the right places to drive the turbopump and simultaneously keep the thrust chamber from melting. The heat conditioned fuel and oxidizer come together and burn inside the combustion chamber to provide thrust. The efforts to make multiple parts precisely fit together and not leak after experiencing cryogenic temperatures on one-side and combustion temperatures on the other is quite challenging. Additive manufacturing has the potential to significantly reduce the time and cost of making rocket parts like the copper liner and Nickel-alloy jackets found in rocket combustion chambers where super-cold cryogenic propellants are heated and mixed to the extreme temperatures needed to propel rockets in space. The Selective Laser Melting (SLM) machine fuses 8,255 layers of copper powder to make a section of the chamber in 10 days. Machining an equivalent part and assembling it with welding and brazing techniques could take months to accomplish with potential failures or leaks that could require fixes. The design process is also enhanced since it does not require the 3D model to be converted to 2-D drawings. The design and fabrication process

Zebrafish Models of Prader-Willi Syndrome: Fast Track to Pharmacotherapeutics

Directory of Open Access Journals (Sweden)

Emma D. Spikol

2016-03-01

Full Text Available Prader-Willi syndrome (PWS is a rare genetic neurodevelopmental disorder characterized by an insatiable appetite, leading to chronic overeating and obesity. Additional features include short stature, intellectual disability, behavioral problems and incomplete sexual development. Although significant progress has been made in understanding the genetic basis of PWS, the mechanisms underlying the pathogenesis of the disorder remain poorly understood. Treatment for PWS consists mainly of palliative therapies; curative therapies are sorely needed. Zebrafish, Danio rerio, represent a promising way forward for elucidating physiological problems such as obesity and identifying new pharmacotherapeutic options for PWS. Over the last decade, an increased appreciation for the highly conserved biology among vertebrates and the ability to perform high-throughput drug screening has seen an explosion in the use of zebrafish for disease modeling and drug discovery. Here, we review recent advances in developing zebrafish models of human disease. Aspects of zebrafish genetics and physiology that are relevant to PWS will be discussed, and the advantages and disadvantages of zebrafish models will be contrasted with current animal models for this syndrome. Finally, we will present a paradigm for drug screening in zebrafish that is potentially the fastest route for identifying and delivering curative pharmacotherapies to PWS patients.

Multiplex conditional mutagenesis in zebrafish using the CRISPR/Cas system.

Science.gov (United States)

Yin, L; Maddison, L A; Chen, W

2016-01-01

The clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein (Cas) system is a powerful tool for genome editing in numerous organisms. However, the system is typically used for gene editing throughout the entire organism. Tissue and temporal specific mutagenesis is often desirable to determine gene function in a specific stage or tissue and to bypass undesired consequences of global mutations. We have developed the CRISPR/Cas system for conditional mutagenesis in transgenic zebrafish using tissue-specific and/or inducible expression of Cas9 and U6-driven expression of sgRNA. To allow mutagenesis of multiple targets, we have isolated four distinct U6 promoters and designed Golden Gate vectors to easily assemble transgenes with multiple sgRNAs. We provide experimental details on the reagents and applications for multiplex conditional mutagenesis in zebrafish. Copyright © 2016 Elsevier Inc. All rights reserved.

Metastatic behaviour of primary human tumours in a zebrafish xenotransplantation model

International Nuclear Information System (INIS)

Marques, Ines J; Bagowski, Christoph P; Weiss, Frank Ulrich; Vlecken, Danielle H; Nitsche, Claudia; Bakkers, Jeroen; Lagendijk, Anne K; Partecke, Lars Ivo; Heidecke, Claus-Dieter; Lerch, Markus M

2009-01-01

Aberrant regulation of cell migration drives progression of many diseases, including cancer cell invasion and metastasis formation. Analysis of tumour invasion and metastasis in living organisms to date is cumbersome and involves difficult and time consuming investigative techniques. For primary human tumours we establish here a simple, fast, sensitive and cost-effective in vivo model to analyse tumour invasion and metastatic behaviour. We fluorescently labelled small explants from gastrointestinal human tumours and investigated their metastatic behaviour after transplantation into zebrafish embryos and larvae. The transparency of the zebrafish embryos allows to follow invasion, migration and micrometastasis formation in real-time. High resolution imaging was achieved through laser scanning confocal microscopy of live zebrafish. In the transparent zebrafish embryos invasion, circulation of tumour cells in blood vessels, migration and micrometastasis formation can be followed in real-time. Xenografts of primary human tumours showed invasiveness and micrometastasis formation within 24 hours after transplantation, which was absent when non-tumour tissue was implanted. Furthermore, primary human tumour cells, when organotopically implanted in the zebrafish liver, demonstrated invasiveness and metastatic behaviour, whereas primary control cells remained in the liver. Pancreatic tumour cells showed no metastatic behaviour when injected into cloche mutant embryos, which lack a functional vasculature. Our results show that the zebrafish is a useful in vivo animal model for rapid analysis of invasion and metastatic behaviour of primary human tumour specimen

Use of zebrafish to study Shigella infection

Science.gov (United States)

Duggan, Gina M.

2018-01-01

ABSTRACT Shigella is a leading cause of dysentery worldwide, responsible for up to 165 million cases of shigellosis each year. Shigella is also recognised as an exceptional model pathogen to study key issues in cell biology and innate immunity. Several infection models have been useful to explore Shigella biology; however, we still lack information regarding the events taking place during the Shigella infection process in vivo. Here, we discuss a selection of mechanistic insights recently gained from studying Shigella infection of zebrafish (Danio rerio), with a focus on cytoskeleton rearrangements and cellular immunity. We also discuss how infection of zebrafish can be used to investigate new concepts underlying infection control, including emergency granulopoiesis and the use of predatory bacteria to combat antimicrobial resistance. Collectively, these insights illustrate how Shigella infection of zebrafish can provide fundamental advances in our understanding of bacterial pathogenesis and vertebrate host defence. This information should also provide vital clues for the discovery of new therapeutic strategies against infectious disease in humans. PMID:29590642

Use of zebrafish to study Shigella infection

Directory of Open Access Journals (Sweden)

Gina M. Duggan

2018-02-01

Full Text Available Shigella is a leading cause of dysentery worldwide, responsible for up to 165 million cases of shigellosis each year. Shigella is also recognised as an exceptional model pathogen to study key issues in cell biology and innate immunity. Several infection models have been useful to explore Shigella biology; however, we still lack information regarding the events taking place during the Shigella infection process in vivo. Here, we discuss a selection of mechanistic insights recently gained from studying Shigella infection of zebrafish (Danio rerio, with a focus on cytoskeleton rearrangements and cellular immunity. We also discuss how infection of zebrafish can be used to investigate new concepts underlying infection control, including emergency granulopoiesis and the use of predatory bacteria to combat antimicrobial resistance. Collectively, these insights illustrate how Shigella infection of zebrafish can provide fundamental advances in our understanding of bacterial pathogenesis and vertebrate host defence. This information should also provide vital clues for the discovery of new therapeutic strategies against infectious disease in humans.

A Low-Cost Fluorescent Sensor for pCO2 Measurements

Directory of Open Access Journals (Sweden)

Xudong Ge

2014-04-01

Full Text Available Global warming is believed to be caused by increasing amounts of greenhouse gases (mostly CO2 discharged into the environment by human activity. In addition to an increase in environmental temperature, an increased CO2 level has also led to ocean acidification. Ocean acidification and rising temperatures have disrupted the water’s ecological balance, killing off some plant and animal species, while encouraging the overgrowth of others. To minimize the effect of global warming on local ecosystem, there is a strong need to implement ocean observing systems to monitor the effects of anthropogenic CO2 and the impacts thereof on ocean biological productivity. Here, we describe the development of a low-cost fluorescent sensor for pCO2 measurements. The detector was exclusively assembled with low-cost optics and electronics, so that it would be affordable enough to be deployed in great numbers. The system has several novel features, such as an ideal 90° separation between excitation and emission, a beam combiner, a reference photodetector, etc. Initial tests showed that the system was stable and could achieve a high resolution despite the low cost.

Self-Controlling Rig for Jaw Crusher Assembly

OpenAIRE

Saurabh Jadhav; Anup Pawar

2017-01-01

The aim of the work is to develop a method for easy assembly of the bearing in the housing by standardized way. The assembly of bearing should take place on the atomized set up. Based on this method a assembly setup was constructed which enables to assembly of the shaft with bearing of different models of jaw crusher. First tests were done with manual alignment and it shows that with proper alignment shaft assembly is very easy operation and also safe. Results of those tests show that the dev...

Pointo - a Low Cost Solution to Point Cloud Processing

Science.gov (United States)

Houshiar, H.; Winkler, S.

2017-11-01

With advance in technology access to data especially 3D point cloud data becomes more and more an everyday task. 3D point clouds are usually captured with very expensive tools such as 3D laser scanners or very time consuming methods such as photogrammetry. Most of the available softwares for 3D point cloud processing are designed for experts and specialists in this field and are usually very large software packages containing variety of methods and tools. This results in softwares that are usually very expensive to acquire and also very difficult to use. Difficulty of use is caused by complicated user interfaces that is required to accommodate a large list of features. The aim of these complex softwares is to provide a powerful tool for a specific group of specialist. However they are not necessary required by the majority of the up coming average users of point clouds. In addition to complexity and high costs of these softwares they generally rely on expensive and modern hardware and only compatible with one specific operating system. Many point cloud customers are not point cloud processing experts or willing to spend the high acquisition costs of these expensive softwares and hardwares. In this paper we introduce a solution for low cost point cloud processing. Our approach is designed to accommodate the needs of the average point cloud user. To reduce the cost and complexity of software our approach focuses on one functionality at a time in contrast with most available softwares and tools that aim to solve as many problems as possible at the same time. Our simple and user oriented design improve the user experience and empower us to optimize our methods for creation of an efficient software. In this paper we introduce Pointo family as a series of connected softwares to provide easy to use tools with simple design for different point cloud processing requirements. PointoVIEWER and PointoCAD are introduced as the first components of the Pointo family to provide a

Low-cost Citizen Science Balloon Platform for Measuring Air Pollutants to Improve Satellite Retrieval Algorithms

Science.gov (United States)

Potosnak, M. J.; Beck-Winchatz, B.; Ritter, P.

2016-12-01

High-altitude balloons (HABs) are an engaging platform for citizen science and formal and informal STEM education. However, the logistics of launching, chasing and recovering a payload on a 1200 g or 1500 g balloon can be daunting for many novice school groups and citizen scientists, and the cost can be prohibitive. In addition, there are many interesting scientific applications that do not require reaching the stratosphere, including measuring atmospheric pollutants in the planetary boundary layer. With a large number of citizen scientist flights, these data can be used to constrain satellite retrieval algorithms. In this poster presentation, we discuss a novel approach based on small (30 g) balloons that are cheap and easy to handle, and low-cost tracking devices (SPOT trackers for hikers) that do not require a radio license. Our scientific goal is to measure air quality in the lower troposphere. For example, particulate matter (PM) is an air pollutant that varies on small spatial scales and has sources in rural areas like biomass burning and farming practices such as tilling. Our HAB platform test flight incorporates an optical PM sensor, an integrated single board computer that records the PM sensor signal in addition to flight parameters (pressure, location and altitude), and a low-cost tracking system. Our goal is for the entire platform to cost less than $500. While the datasets generated by these flights are typically small, integrating a network of flight data from citizen scientists into a form usable for comparison to satellite data will require big data techniques.

Calibrating EASY-Care independence scale to improve accuracy

Science.gov (United States)

Jotheeswaran, A. T.; Dias, Amit; Philp, Ian; Patel, Vikram; Prince, Martin

2016-01-01

Background there is currently limited support for the reliability and validity of the EASY-Care independence scale, with little work carried out in low- or middle-income countries. Therefore, we assessed the internal construct validity and hierarchical and classical scaling properties among frail dependent older people in the community. Objective we assessed the internal construct validity and hierarchical and classical scaling properties among frail dependent older people in the community. Methods three primary care physicians administered EASY-Care comprehensive geriatric assessment for 150 frail and/or dependent older people in the primary care setting. A Mokken model was applied to investigate hierarchical scaling properties of EASY-Care independence scale, and internal consistency (Cronbach's alpha) of the scale was also examined. Results we found that EASY-Care independence scale is highly internally consistent and is a strong hierarchical scale, hence providing strong evidence for unidimensionality. However, two items in the scale (unable to use telephone and manage finances) had much lower item Loevinger H coefficients than others. Exclusion of these two items improved the overall internal consistency of the scale. Conclusions the strong performance of the EASY-Care independence scale among community-dwelling frail older people is encouraging. This study confirms that EASY-Care independence scale is highly internally consistent and a strong hierarchical scale. PMID:27496925

Metal-free supercapacitor with aqueous electrolyte and low-cost carbon materials

Science.gov (United States)

Blomquist, Nicklas; Wells, Thomas; Andres, Britta; Bäckström, Joakim; Forsberg, Sven; Olin, Håkan

2017-01-01

Electric double-layer capacitors (EDLCs) or supercapacitors (SCs) are fast energy storage devices with high pulse efficiency and superior cyclability, which makes them useful in various applications including electronics, vehicles and grids. Aqueous SCs are considered to be more environmentally friendly than those based on organic electrolytes. Because of the corrosive nature of the aqueous environment, however, expensive electrochemically stable materials are needed for the current collectors and electrodes in aqueous SCs. This results in high costs for a given energy-storage capacity. To address this, we developed a novel low-cost aqueous SC using graphite foil as the current collector and a mix of graphene, nanographite, simple water-purification carbons and nanocellulose as electrodes. The electrodes were coated directly onto the graphite foil by using casting frames and the SCs were assembled in a pouch cell design. With this approach, we achieved a material cost reduction of greater than 90% while maintaining approximately one-half of the specific capacitance of a commercial unit, thus demonstrating that the proposed SC can be an environmentally friendly, low-cost alternative to conventional SCs.

Performance analysis of a compact and low-cost mapping-grade mobile laser scanning system

Science.gov (United States)

Julge, Kalev; Vajakas, Toivo; Ellmann, Artu

2017-10-01

The performance of a low-cost, self-contained, compact, and easy to deploy mapping-grade mobile laser scanning (MLS) system, which is composed of a light detection and ranging sensor Velodyne VLP-16 and a dual antenna global navigation satellite system/inertial navigation system SBG Systems Ellipse-D, is analyzed. The field tests were carried out in car-mounted and backpack modes for surveying road engineering structures (such as roads, parking lots, underpasses, and tunnels) and coastal erosion zones, respectively. The impact of applied calculation principles on trajectory postprocessing, direct georeferencing, and the theoretical accuracy of the system is analyzed. A calibration method, based on Bound Optimization BY Quadratic Approximation, for finding the boresight angles of an MLS system is proposed. The resulting MLS point clouds are compared with high-accuracy static terrestrial laser scanning data and survey-grade MLS data from a commercially manufactured MLS system. The vertical, horizontal, and relative accuracy are assessed-the root-mean-square error (RMSE) values were determined to be 8, 15, and 3 cm, respectively. Thus, the achieved mapping-grade accuracy demonstrates that this relatively compact and inexpensive self-assembled MLS can be successfully used for surveying the geometry and deformations of terrain, buildings, road, and other engineering structures.

BMP signaling modulates hepcidin expression in zebrafish embryos independent of hemojuvelin.

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Yann Gibert

2011-01-01

Full Text Available Hemojuvelin (Hjv, a member of the repulsive-guidance molecule (RGM family, upregulates transcription of the iron regulatory hormone hepcidin by activating the bone morphogenetic protein (BMP signaling pathway in mammalian cells. Mammalian models have identified furin, neogenin, and matriptase-2 as modifiers of Hjv's function. Using the zebrafish model, we evaluated the effects of hjv and its interacting proteins on hepcidin expression during embryonic development. We found that hjv is strongly expressed in the notochord and somites of the zebrafish embryo and that morpholino knockdown of hjv impaired the development of these structures. Knockdown of hjv or other hjv-related genes, including zebrafish orthologs of furin or neogenin, however, failed to decrease hepcidin expression relative to liver size. In contrast, overexpression of bmp2b or knockdown of matriptase-2 enhanced the intensity and extent of hepcidin expression in zebrafish embryos, but this occurred in an hjv-independent manner. Furthermore, we demonstrated that zebrafish hjv can activate the human hepcidin promoter and enhance BMP responsive gene expression in vitro, but is expressed at low levels in the zebrafish embryonic liver. Taken together, these data support an alternative mechanism for hepcidin regulation during zebrafish embryonic development, which is independent of hjv.

Adaptive response to ionising radiation induced by cadmium in zebrafish embryos

International Nuclear Information System (INIS)

Choi, V W Y; Ng, C Y P; Kong, M K Y; Yu, K N; Cheng, S H

2013-01-01

An adaptive response is a biological response where the exposure of cells or animals to a low priming exposure induces mechanisms that protect the cells or animals against the detrimental effects of a subsequent larger challenging exposure. In realistic environmental situations, living organisms can be exposed to a mixture of stressors, and the resultant effects due to such exposures are referred to as multiple stressor effects. In the present work we demonstrated, via quantification of apoptosis in the embryos, that embryos of the zebrafish (Danio rerio) subjected to a priming exposure provided by one environmental stressor (cadmium in micromolar concentrations) could undergo an adaptive response against a subsequent challenging exposure provided by another environmental stressor (alpha particles). We concluded that zebrafish embryos treated with 1 to 10 μM Cd at 5 h postfertilisation (hpf) for both 1 and 5 h could undergo an adaptive response against subsequent ∼4.4 mGy alpha-particle irradiation at 10 hpf, which could be interpreted as an antagonistic multiple stressor effect between Cd and ionising radiation. The zebrafish has become a popular vertebrate model for studying the in vivo response to ionising radiation. As such, our results suggested that multiple stressor effects should be carefully considered for human radiation risk assessment since the risk may be perturbed by another environmental stressor such as a heavy metal. (paper)

Genetic analysis of male reproductive success in relation to density in the zebrafish, Danio rerio

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Jordan William C

2006-04-01

Full Text Available Abstract Background We used behavioural and genetic data to investigate the effects of density on male reproductive success in the zebrafish, Danio rerio. Based on previous measurements of aggression and courtship behaviour by territorial males, we predicted that they would sire more offspring than non-territorial males. Results Microsatellite analysis of paternity showed that at low densities territorial males had higher reproductive success than non-territorial males. However, at high density territorial males were no more successful than non-territorials and the sex difference in the opportunity for sexual selection, based on the parameter Imates, was low. Conclusion Male zebrafish exhibit two distinct mating tactics; territoriality and active pursuit of females. Male reproductive success is density dependent and the opportunity for sexual selection appears to be weak in this species.

Quantitative analysis of transmittance and photoluminescence using a low cost apparatus

International Nuclear Information System (INIS)

Onorato, P; Malgieri, M; De Ambrosis, A

2016-01-01

We show how a low cost spectrometer, based on the use of inexpensive diffraction transmission gratings coupled with a commercial digital photo camera or a cellphone, can be assembled and employed to obtain quantitative spectra of different sources. In particular, we discuss its use in studying the spectra of fluorescent colored ink, used in highlighting pens, for which the transmission band and the emission peaks are measured and related to the ink color. (paper)

Quantitative analysis of transmittance and photoluminescence using a low cost apparatus

Science.gov (United States)

Onorato, P.; Malgieri, M.; De Ambrosis, A.

2016-01-01

We show how a low cost spectrometer, based on the use of inexpensive diffraction transmission gratings coupled with a commercial digital photo camera or a cellphone, can be assembled and employed to obtain quantitative spectra of different sources. In particular, we discuss its use in studying the spectra of fluorescent colored ink, used in highlighting pens, for which the transmission band and the emission peaks are measured and related to the ink color.

Low-cost, solution processable carbon nanotube supercapacitors and their characterization

Science.gov (United States)

Lehtimäki, Suvi; Tuukkanen, Sampo; Pörhönen, Juho; Moilanen, Pasi; Virtanen, Jorma; Honkanen, Mari; Lupo, Donald

2014-06-01

We report ecological and low-cost carbon nanotube (CNT) supercapacitors fabricated using a simple, scalable solution processing method, where the use of a highly porous and electrically conductive active material eliminates the need for a current collector. Electrodes were fabricated on a poly(ethylene terephthalate) substrate from a printable multi-wall CNT ink, where the CNTs are solubilized in water using xylan as a dispersion agent. The dispersion method facilitates a very high concentration of CNTs in the ink. Supercapacitors were assembled using a paper separator and an aqueous NaCl electrolyte and the devices were characterized with a galvanostatic discharge method defined by an industrial standard. The capacitance of the 2 cm^2 devices was 6 mF/cm^2 (2.3 F/g) and equivalent series resistance 80 Ω . Low-cost supercapacitors fabricated from safe and environmentally friendly materials have potential applications as energy storage devices in ubiquitous and autonomous intelligence as well as in disposable low-end products.

Three-dimensional assemblies of graphene prepared by a novel chemical reduction-induced self-assembly method

KAUST Repository

Zhang, Lianbin; Chen, Guoying; Hedhili, Mohamed N.; Zhang, Hongnan; Wang, Peng

2012-01-01

In this study, three-dimensional (3D) graphene assemblies are prepared from graphene oxide (GO) by a facile in situ reduction-assembly method, using a novel, low-cost, and environment-friendly reducing medium which is a combination of oxalic acid

Real-Time Monitoring and Analysis of Zebrafish Electrocardiogram with Anomaly Detection

Directory of Open Access Journals (Sweden)

Michael Lenning

2017-12-01

Full Text Available Heart disease is the leading cause of mortality in the U.S. with approximately 610,000 people dying every year. Effective therapies for many cardiac diseases are lacking, largely due to an incomplete understanding of their genetic basis and underlying molecular mechanisms. Zebrafish (Danio rerio are an excellent model system for studying heart disease as they enable a forward genetic approach to tackle this unmet medical need. In recent years, our team has been employing electrocardiogram (ECG as an efficient tool to study the zebrafish heart along with conventional approaches, such as immunohistochemistry, DNA and protein analyses. We have overcome various challenges in the small size and aquatic environment of zebrafish in order to obtain ECG signals with favorable signal-to-noise ratio (SNR, and high spatial and temporal resolution. In this paper, we highlight our recent efforts in zebrafish ECG acquisition with a cost-effective simplified microelectrode array (MEA membrane providing multi-channel recording, a novel multi-chamber apparatus for simultaneous screening, and a LabVIEW program to facilitate recording and processing. We also demonstrate the use of machine learning-based programs to recognize specific ECG patterns, yielding promising results with our current limited amount of zebrafish data. Our solutions hold promise to carry out numerous studies of heart diseases, drug screening, stem cell-based therapy validation, and regenerative medicine.

Low cost carriers in the Middle East and North Africa: Prospects and strategies

OpenAIRE

Morrison, W.G.; Mason, Keith J.

2016-01-01

We examine socio-economic indicators relevant to ‘low cost carriers’ (LCCs) in the Middle East and North Africa (MENA) and review the evolution of air transport liberalization and air service agreements in the region. We analyse the business strategies of MENA-based LCCs and using a benchmarking methodology, we compare the business strategy of Air Arabia Group with those of dominant European LCCs EasyJet and Ryanair. Our economic development indicators suggest future potential for...

A low-cost spectrometer for NMR measurements in the Earth's magnetic field

International Nuclear Information System (INIS)

Michal, Carl A

2010-01-01

We describe and demonstrate an inexpensive, easy-to-build, portable spectrometer for nuclear magnetic resonance measurements in the Earth's magnetic field. The spectrometer is based upon a widely available inexpensive microcontroller, which acts as a pulse programmer, audio-frequency synthesizer and digitizer, replacing what are typically the most expensive specialized components of the system. The microcontroller provides the capability to execute arbitrarily long and complicated sequences of phase-coherent, phase-modulated excitation pulses and acquire data sets of unlimited duration. Suitably packaged, the spectrometer is amenable to measurements in the research lab, in the field or in the teaching lab. The choice of components was heavily weighted by cost and availability, but required no significant sacrifice in performance. Using an existing personal computer, the resulting design can be assembled for as little as US$200. The spectrometer performance is demonstrated with spin-echo and Carr–Purcell–Meiboom–Gill pulse sequences on a water sample

A low-cost spectrometer for NMR measurements in the Earth's magnetic field

Science.gov (United States)

Michal, Carl A.

2010-10-01

We describe and demonstrate an inexpensive, easy-to-build, portable spectrometer for nuclear magnetic resonance measurements in the Earth's magnetic field. The spectrometer is based upon a widely available inexpensive microcontroller, which acts as a pulse programmer, audio-frequency synthesizer and digitizer, replacing what are typically the most expensive specialized components of the system. The microcontroller provides the capability to execute arbitrarily long and complicated sequences of phase-coherent, phase-modulated excitation pulses and acquire data sets of unlimited duration. Suitably packaged, the spectrometer is amenable to measurements in the research lab, in the field or in the teaching lab. The choice of components was heavily weighted by cost and availability, but required no significant sacrifice in performance. Using an existing personal computer, the resulting design can be assembled for as little as US200. The spectrometer performance is demonstrated with spin-echo and Carr-Purcell-Meiboom-Gill pulse sequences on a water sample.

Directed Differentiation of Zebrafish Pluripotent Embryonic Cells to Functional Cardiomyocytes

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Yao Xiao

2016-09-01

Full Text Available A cardiomyocyte differentiation in vitro system from zebrafish embryos remains to be established. Here, we have determined pluripotency window of zebrafish embryos by analyzing their gene-expression patterns of pluripotency factors together with markers of three germ layers, and have found that zebrafish undergoes a very narrow period of pluripotency maintenance from zygotic genome activation to a brief moment after oblong stage. Based on the pluripotency and a combination of appropriate conditions, we established a rapid and efficient method for cardiomyocyte generation in vitro from primary embryonic cells. The induced cardiomyocytes differentiated into functional and specific cardiomyocyte subtypes. Notably, these in vitro generated cardiomyocytes exhibited typical contractile kinetics and electrophysiological features. The system provides a new paradigm of cardiomyocyte differentiation from primary embryonic cells in zebrafish. The technology provides a new platform for the study of heart development and regeneration, in addition to drug discovery, disease modeling, and assessment of cardiotoxic agents.

Zebrafish Expression Ontology of Gene Sets (ZEOGS): A Tool to Analyze Enrichment of Zebrafish Anatomical Terms in Large Gene Sets

Science.gov (United States)

Marsico, Annalisa

2013-01-01

Abstract The zebrafish (Danio rerio) is an established model organism for developmental and biomedical research. It is frequently used for high-throughput functional genomics experiments, such as genome-wide gene expression measurements, to systematically analyze molecular mechanisms. However, the use of whole embryos or larvae in such experiments leads to a loss of the spatial information. To address this problem, we have developed a tool called Zebrafish Expression Ontology of Gene Sets (ZEOGS) to assess the enrichment of anatomical terms in large gene sets. ZEOGS uses gene expression pattern data from several sources: first, in situ hybridization experiments from the Zebrafish Model Organism Database (ZFIN); second, it uses the Zebrafish Anatomical Ontology, a controlled vocabulary that describes connected anatomical structures; and third, the available connections between expression patterns and anatomical terms contained in ZFIN. Upon input of a gene set, ZEOGS determines which anatomical structures are overrepresented in the input gene set. ZEOGS allows one for the first time to look at groups of genes and to describe them in terms of shared anatomical structures. To establish ZEOGS, we first tested it on random gene selections and on two public microarray datasets with known tissue-specific gene expression changes. These tests showed that ZEOGS could reliably identify the tissues affected, whereas only very few enriched terms to none were found in the random gene sets. Next we applied ZEOGS to microarray datasets of 24 and 72 h postfertilization zebrafish embryos treated with beclomethasone, a potent glucocorticoid. This analysis resulted in the identification of several anatomical terms related to glucocorticoid-responsive tissues, some of which were stage-specific. Our studies highlight the ability of ZEOGS to extract spatial information from datasets derived from whole embryos, indicating that ZEOGS could be a useful tool to automatically analyze gene

Zebrafish Expression Ontology of Gene Sets (ZEOGS): a tool to analyze enrichment of zebrafish anatomical terms in large gene sets.

Science.gov (United States)

Prykhozhij, Sergey V; Marsico, Annalisa; Meijsing, Sebastiaan H

2013-09-01

The zebrafish (Danio rerio) is an established model organism for developmental and biomedical research. It is frequently used for high-throughput functional genomics experiments, such as genome-wide gene expression measurements, to systematically analyze molecular mechanisms. However, the use of whole embryos or larvae in such experiments leads to a loss of the spatial information. To address this problem, we have developed a tool called Zebrafish Expression Ontology of Gene Sets (ZEOGS) to assess the enrichment of anatomical terms in large gene sets. ZEOGS uses gene expression pattern data from several sources: first, in situ hybridization experiments from the Zebrafish Model Organism Database (ZFIN); second, it uses the Zebrafish Anatomical Ontology, a controlled vocabulary that describes connected anatomical structures; and third, the available connections between expression patterns and anatomical terms contained in ZFIN. Upon input of a gene set, ZEOGS determines which anatomical structures are overrepresented in the input gene set. ZEOGS allows one for the first time to look at groups of genes and to describe them in terms of shared anatomical structures. To establish ZEOGS, we first tested it on random gene selections and on two public microarray datasets with known tissue-specific gene expression changes. These tests showed that ZEOGS could reliably identify the tissues affected, whereas only very few enriched terms to none were found in the random gene sets. Next we applied ZEOGS to microarray datasets of 24 and 72 h postfertilization zebrafish embryos treated with beclomethasone, a potent glucocorticoid. This analysis resulted in the identification of several anatomical terms related to glucocorticoid-responsive tissues, some of which were stage-specific. Our studies highlight the ability of ZEOGS to extract spatial information from datasets derived from whole embryos, indicating that ZEOGS could be a useful tool to automatically analyze gene expression

A low cost high resolution pattern generator for electron-beam lithography

International Nuclear Information System (INIS)

Pennelli, G.; D'Angelo, F.; Piotto, M.; Barillaro, G.; Pellegrini, B.

2003-01-01

A simple, very low cost pattern generator for electron-beam lithography is presented. When it is applied to a scanning electron microscope, the system allows a high precision positioning of the beam for lithography of very small structures. Patterns are generated by a suitable software implemented on a personal computer, by using very simple functions, allowing an easy development of new writing strategies for a great adaptability to different user necessities. Hardware solutions, as optocouplers and battery supply, have been implemented for reduction of noise and disturbs on the voltages controlling the positioning of the beam

Improved somatic mutagenesis in zebrafish using transcription activator-like effector nucleases (TALENs.

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Finola E Moore

Full Text Available Zinc Finger Nucleases (ZFNs made by Context-Dependent Assembly (CoDA and Transcription Activator-Like Effector Nucleases (TALENs provide robust and user-friendly technologies for efficiently inactivating genes in zebrafish. These designer nucleases bind to and cleave DNA at particular target sites, inducing error-prone repair that can result in insertion or deletion mutations. Here, we assess the relative efficiencies of these technologies for inducing somatic DNA mutations in mosaic zebrafish. We find that TALENs exhibited a higher success rate for obtaining active nucleases capable of inducing mutations than compared with CoDA ZFNs. For example, all six TALENs tested induced DNA mutations at genomic target sites while only a subset of CoDA ZFNs exhibited detectable rates of mutagenesis. TALENs also exhibited higher mutation rates than CoDA ZFNs that had not been pre-screened using a bacterial two-hybrid assay, with DNA mutation rates ranging from 20%-76.8% compared to 1.1%-3.3%. Furthermore, the broader targeting range of TALENs enabled us to induce mutations at the methionine translation start site, sequences that were not targetable using the CoDA ZFN platform. TALENs exhibited similar toxicity to CoDA ZFNs, with >50% of injected animals surviving to 3 days of life. Taken together, our results suggest that TALEN technology provides a robust alternative to CoDA ZFNs for inducing targeted gene-inactivation in zebrafish, making it a preferred technology for creating targeted knockout mutants in zebrafish.

Epilepsy, Behavioral Abnormalities, and Physiological Comorbidities in Syntaxin-Binding Protein 1 (STXBP1 Mutant Zebrafish.

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Brian P Grone

Full Text Available Mutations in the synaptic machinery gene syntaxin-binding protein 1, STXBP1 (also known as MUNC18-1, are linked to childhood epilepsies and other neurodevelopmental disorders. Zebrafish STXBP1 homologs (stxbp1a and stxbp1b have highly conserved sequence and are prominently expressed in the larval zebrafish brain. To understand the functions of stxbp1a and stxbp1b, we generated loss-of-function mutations using CRISPR/Cas9 gene editing and studied brain electrical activity, behavior, development, heart physiology, metabolism, and survival in larval zebrafish. Homozygous stxbp1a mutants exhibited a profound lack of movement, low electrical brain activity, low heart rate, decreased glucose and mitochondrial metabolism, and early fatality compared to controls. On the other hand, homozygous stxbp1b mutants had spontaneous electrographic seizures, and reduced locomotor activity response to a movement-inducing "dark-flash" visual stimulus, despite showing normal metabolism, heart rate, survival, and baseline locomotor activity. Our findings in these newly generated mutant lines of zebrafish suggest that zebrafish recapitulate clinical phenotypes associated with human syntaxin-binding protein 1 mutations.

Can easy-to-use software deliver effective e-learning in dental education? A randomised controlled study.

Science.gov (United States)

Woelber, J P; Hilbert, T S; Ratka-Krüger, P

2012-08-01

For the production of computer-based learning environments, a wide range of software solutions can be used which differ not only in their functionality but also vary in cost and ease to program. The aim of our study was to evaluate the overall efficiency and student's perception of two case-based e-learning programs that were produced with either an easy-to-use or a complex software. Eighty-five dental students were randomly assigned to one of two experimental groups. One group studied with a laborious, high-interactive e-learning program (complex-software group). The second group studied within a low-interactive learning environment (easy-software group) that was easy to be programmed. Both programs identically referred to a case report on localised aggressive periodontitis. Learning outcome was tested by a pre- and post-test. Furthermore, questionnaires on workload, motivation, perceived usefulness and perceived learning outcome were used. Learners in the easy-software group showed better results in the post-test F(1, 82) = 4.173, P software tools have the potential to be beneficial in dental education. Students were showing a high acceptance and ability in using both e-learning environments. We conclude that e-learning programs for case-based learning do not have to be overly laborious to program to be useful. Based on our results, we want to encourage instructors to produce case-based e-learning tools with easy-to-use software. © 2012 John Wiley & Sons A/S.

Influence of carbon nanotube length on toxicity to zebrafish embryos

Directory of Open Access Journals (Sweden)

Cheng J

2012-07-01

Full Text Available Jinping Cheng,1,2 Shuk Han Cheng11Department of Biology and Chemistry, City University of Hong Kong, Hong Kong; 2State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, ChinaAbstract: There is currently a large difference of opinion in nanotoxicology studies of nanomaterials. There is concern about why some studies have indicated that there is strong toxicity, while others have not. In this study, the length of carbon nanotubes greatly affected their toxicity in zebrafish embryos. Multiwalled carbon nanotubes (MWCNTs were sonicated in a nitric acid solution for 24 hours and 48 hours. The modified MWCNTs were tested in early developing zebrafish embryo. MWCNTs prepared with the longer sonication time resulted in severe developmental toxicity; however, the shorter sonication time did not induce any obvious toxicity in the tested developing zebrafish embryos. The cellular and molecular changes of the affected zebrafish embryos were studied and the observed phenotypes scored. This study suggests that length plays an important role in the in vivo toxicity of functionalized CNTs. This study will help in furthering the understanding on current differences in toxicity studies of nanomaterials.Keywords: length, carbon nanotubes, sonication, developmental toxicity, zebrafish

An assessment of the transportation costs of shipping non-fuel assembly hardware to FWMS facilities

International Nuclear Information System (INIS)

Shappert, L.B.; Joy, D.S.; Johnson, P.E.; Danese, F.L.; Best, R.E.

1991-01-01

This study examines the cost of using Department of Energy (DOE) Office of Civilian Radioactive Waste Management (OCRWM) Initiative I casks for transporting 62,700 MTU of spent fuel plus associated non-fuel assembly hardware (NFAH) between reactor sites and either a monitored retrievable storage (MRS) or a repository facility. The study further considers the benefits of increasing the cell size of the Initiative I BWR cask baskets to accommodate the fuel plus channels (which also would decrease the capacity of the cask to carry BWR fuel without channels) and the use of a commercial, non-spent-fuel cask to carry compacted NFAH that could not be shipped integrally. Costs that are developed involve transportation charges, capital costs for casks, and canning costs of NFAH that have been separated from the fuel. The results indicate that significant cost savings are possible if NFAH is accepted into the Federal Waste Management System (FWMS) that is either integral with the spent fuel, or consolidated if it has been separated. Shipment of unconsolidated NFAH is very expensive. Transportation costs for shipping to a western repository are approximately 50 to 75% higher than the costs for shipping to an eastern MRS

Industrializing Offshore Wind Power with Serial Assembly and Lower-cost Deployment - Final Report

Energy Technology Data Exchange (ETDEWEB)

Kempton, Willett [Univ. of Delaware, Newark, DE (United States)

2017-12-11

A team of engineers and contractors has developed a method to move offshore wind installation toward lower cost, faster deployment, and lower environmental impact. A combination of methods, some incremental and some breaks from past practice, interact to yield multiple improvements. Three designs were evaluated based on detailed engineering: 1) a 5 MW turbine on a jacket with pin piles (base case), 2) a 10 MW turbine on a conventional jacket with pin piles, assembled at sea, and 3) a 10 MW turbine on tripod jacket with suction buckets (caissons) and with complete turbine assembly on-shore. The larger turbine, assembly ashore, and the use of suction buckets together substantially reduce capital cost of offshore wind projects. Notable capital cost reductions are: changing from 5 MW to 10 MW turbine, a 31% capital cost reduction, and assembly on land then single-piece install at sea an additional 9% capital cost reduction. An estimated Design 4) estimates further cost reduction when equipment and processes of Design 3) are optimized, rather than adapted to existing equipment and process. Cost of energy for each of the four Designs are also calculated, yielding approximately the same percentage reductions. The methods of Design 3) analyzed here include accepted structures such as suction buckets used in new ways, innovations conceived but previously without engineering and economic validation, combined with new methods not previously proposed. Analysis of Designs 2) and 3) are based on extensive engineering calculations and detailed cost estimates. All design methods can be done with existing equipment, including lift equipment, ports and ships (except that design 4 assumes a more optimized ship). The design team consists of experienced offshore structure designers, heavy lift engineers, wind turbine designers, vessel operators, and marine construction contractors. Comparing the methods based on criteria of cost and deployment speed, the study selected the third design

Dynamic colloidal assembly pathways via low dimensional models

Energy Technology Data Exchange (ETDEWEB)

Yang, Yuguang; Bevan, Michael A., E-mail: mabevan@jhu.edu [Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Thyagarajan, Raghuram; Ford, David M. [Chemical Engineering, University of Massachusetts, Amherst, Massachusetts 01003 (United States)

2016-05-28

Here we construct a low-dimensional Smoluchowski model for electric field mediated colloidal crystallization using Brownian dynamic simulations, which were previously matched to experiments. Diffusion mapping is used to infer dimensionality and confirm the use of two order parameters, one for degree of condensation and one for global crystallinity. Free energy and diffusivity landscapes are obtained as the coefficients of a low-dimensional Smoluchowski equation to capture the thermodynamics and kinetics of microstructure evolution. The resulting low-dimensional model quantitatively captures the dynamics of different assembly pathways between fluid, polycrystal, and single crystals states, in agreement with the full N-dimensional data as characterized by first passage time distributions. Numerical solution of the low-dimensional Smoluchowski equation reveals statistical properties of the dynamic evolution of states vs. applied field amplitude and system size. The low-dimensional Smoluchowski equation and associated landscapes calculated here can serve as models for predictive control of electric field mediated assembly of colloidal ensembles into two-dimensional crystalline objects.

Hypothalamic Projections to the Optic Tectum in Larval Zebrafish

Science.gov (United States)

Heap, Lucy A.; Vanwalleghem, Gilles C.; Thompson, Andrew W.; Favre-Bulle, Itia; Rubinsztein-Dunlop, Halina; Scott, Ethan K.

2018-01-01

The optic tectum of larval zebrafish is an important model for understanding visual processing in vertebrates. The tectum has been traditionally viewed as dominantly visual, with a majority of studies focusing on the processes by which tectal circuits receive and process retinally-derived visual information. Recently, a handful of studies have shown a much more complex role for the optic tectum in larval zebrafish, and anatomical and functional data from these studies suggest that this role extends beyond the visual system, and beyond the processing of exclusively retinal inputs. Consistent with this evolving view of the tectum, we have used a Gal4 enhancer trap line to identify direct projections from rostral hypothalamus (RH) to the tectal neuropil of larval zebrafish. These projections ramify within the deepest laminae of the tectal neuropil, the stratum album centrale (SAC)/stratum griseum periventriculare (SPV), and also innervate strata distinct from those innervated by retinal projections. Using optogenetic stimulation of the hypothalamic projection neurons paired with calcium imaging in the tectum, we find rebound firing in tectal neurons consistent with hypothalamic inhibitory input. Our results suggest that tectal processing in larval zebrafish is modulated by hypothalamic inhibitory inputs to the deep tectal neuropil. PMID:29403362

Hypothalamic Projections to the Optic Tectum in Larval Zebrafish

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Lucy A. Heap

2018-01-01

Full Text Available The optic tectum of larval zebrafish is an important model for understanding visual processing in vertebrates. The tectum has been traditionally viewed as dominantly visual, with a majority of studies focusing on the processes by which tectal circuits receive and process retinally-derived visual information. Recently, a handful of studies have shown a much more complex role for the optic tectum in larval zebrafish, and anatomical and functional data from these studies suggest that this role extends beyond the visual system, and beyond the processing of exclusively retinal inputs. Consistent with this evolving view of the tectum, we have used a Gal4 enhancer trap line to identify direct projections from rostral hypothalamus (RH to the tectal neuropil of larval zebrafish. These projections ramify within the deepest laminae of the tectal neuropil, the stratum album centrale (SAC/stratum griseum periventriculare (SPV, and also innervate strata distinct from those innervated by retinal projections. Using optogenetic stimulation of the hypothalamic projection neurons paired with calcium imaging in the tectum, we find rebound firing in tectal neurons consistent with hypothalamic inhibitory input. Our results suggest that tectal processing in larval zebrafish is modulated by hypothalamic inhibitory inputs to the deep tectal neuropil.

Effects of the UV filter benzophenone-3 (oxybenzone) at low concentrations in zebrafish (Danio rerio)

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Blüthgen, Nancy [University of Applied Sciences Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH‐4132 Muttenz (Switzerland); University of Basel, Division of Molecular and Systems Toxicology, Department of Pharmaceutical Sciences, Klingelbergstrasse 50, CH-4056 Basel (Switzerland); Zucchi, Sara [University of Applied Sciences Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH‐4132 Muttenz (Switzerland); Fent, Karl, E-mail: karl.fent@fhnw.ch [University of Applied Sciences Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH‐4132 Muttenz (Switzerland); Swiss Federal Institute of Technology (ETHZ), Department of Environmental Sciences, CH‐8092 Zürich (Switzerland)

2012-09-01

Organic UV filters including benzophenone-3 (BP-3) are widely used to protect humans and materials from damage by UV irradiation. Despite the environmental occurrence of BP-3 in the aquatic environment, little is known about its effects and modes of action. In the present study we assess molecular and physiological effects of BP-3 in adult male zebrafish (Danio rerio) and in eleuthero-embryos by a targeted gene expression approach focusing on the sex hormone system. Fish and embryos are exposed for 14 days and 120 hours post fertilization, respectively, to 2.4–312 μg/L and 8.2–438 μg/L BP-3. Chemical analysis of water and fish demonstrates that BP-3 is partly transformed to benzophenone-1 (BP-1) and both compounds are accumulated in adult fish. Biotransformation to BP-1 is absent in eleuthero-embryos. BP-3 exposure leads to similar alterations of gene expression in both adult fish and eleuthero-embryos. In the brain of adult males esr1, ar and cyp19b are down-regulated at 84 μg/L BP-3. There is no induction of vitellogenin expression by BP-3, both at the transcriptional and protein level. An overall down-regulation of the hsd3b, hsd17b3, hsd11b2 and cyp11b2 transcripts is observed in the testes, suggesting an antiandrogenic activity. No histological changes were observed in the testes after BP-3 treatment. The study leads to the conclusion that low concentrations of BP-3 exhibit similar multiple hormonal activities at the transcription level in two different life stages of zebrafish. Forthcoming studies should show whether this translates to additional physiological effects. Highlights: ► Activity of UV filter benzophenone-3 (BP-3) is assessed in zebrafish. ► BP-3 is partly metabolized to benzophenone-1 by adult fish but not embryos. ► Alterations of gene expression are similar in adult males and embryos. ► Gene expression alterations point to multiple hormonal activity of BP-3.

Efficient methods for targeted mutagenesis in zebrafish using zinc-finger nucleases: data from targeting of nine genes using CompoZr or CoDA ZFNs.

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Raman Sood

Full Text Available Recently, it has been shown that targeted mutagenesis using zinc-finger nucleases (ZFNs and transcription activator-like effector nucleases (TALENs can be used to generate knockout zebrafish lines for analysis of their function and/or developing disease models. A number of different methods have been developed for the design and assembly of gene-specific ZFNs and TALENs, making them easily available to most zebrafish researchers. Regardless of the choice of targeting nuclease, the process of generating mutant fish is similar. It is a time-consuming and multi-step process that can benefit significantly from development of efficient high throughput methods. In this study, we used ZFNs assembled through either the CompoZr (Sigma-Aldrich or the CoDA (context-dependent assembly platforms to generate mutant zebrafish for nine genes. We report our improved high throughput methods for 1 evaluation of ZFNs activity by somatic lesion analysis using colony PCR, eliminating the need for plasmid DNA extractions from a large number of clones, and 2 a sensitive founder screening strategy using fluorescent PCR with PIG-tailed primers that eliminates the stutter bands and accurately identifies even single nucleotide insertions and deletions. Using these protocols, we have generated multiple mutant alleles for seven genes, five of which were targeted with CompoZr ZFNs and two with CoDA ZFNs. Our data also revealed that at least five-fold higher mRNA dose was required to achieve mutagenesis with CoDA ZFNs than with CompoZr ZFNs, and their somatic lesion frequency was lower (<5% when compared to CopmoZr ZFNs (9-98%. This work provides high throughput protocols for efficient generation of zebrafish mutants using ZFNs and TALENs.

DNA Assembly in 3D Printed Fluidics.

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William G Patrick

Full Text Available The process of connecting genetic parts-DNA assembly-is a foundational technology for synthetic biology. Microfluidics present an attractive solution for minimizing use of costly reagents, enabling multiplexed reactions, and automating protocols by integrating multiple protocol steps. However, microfluidics fabrication and operation can be expensive and requires expertise, limiting access to the technology. With advances in commodity digital fabrication tools, it is now possible to directly print fluidic devices and supporting hardware. 3D printed micro- and millifluidic devices are inexpensive, easy to make and quick to produce. We demonstrate Golden Gate DNA assembly in 3D-printed fluidics with reaction volumes as small as 490 nL, channel widths as fine as 220 microns, and per unit part costs ranging from $0.61 to $5.71. A 3D-printed syringe pump with an accompanying programmable software interface was designed and fabricated to operate the devices. Quick turnaround and inexpensive materials allowed for rapid exploration of device parameters, demonstrating a manufacturing paradigm for designing and fabricating hardware for synthetic biology.

Mobius Assembly: A versatile Golden-Gate framework towards universal DNA assembly.

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Andreas I Andreou

Full Text Available Synthetic biology builds upon the foundation of engineering principles, prompting innovation and improvement in biotechnology via a design-build-test-learn cycle. A community-wide standard in DNA assembly would enable bio-molecular engineering at the levels of predictivity and universality in design and construction that are comparable to other engineering fields. Golden Gate Assembly technology, with its robust capability to unidirectionally assemble numerous DNA fragments in a one-tube reaction, has the potential to deliver a universal standard framework for DNA assembly. While current Golden Gate Assembly frameworks (e.g. MoClo and Golden Braid render either high cloning capacity or vector toolkit simplicity, the technology can be made more versatile-simple, streamlined, and cost/labor-efficient, without compromising capacity. Here we report the development of a new Golden Gate Assembly framework named Mobius Assembly, which combines vector toolkit simplicity with high cloning capacity. It is based on a two-level, hierarchical approach and utilizes a low-frequency cutter to reduce domestication requirements. Mobius Assembly embraces the standard overhang designs designated by MoClo, Golden Braid, and Phytobricks and is largely compatible with already available Golden Gate part libraries. In addition, dropout cassettes encoding chromogenic proteins were implemented for cost-free visible cloning screening that color-code different cloning levels. As proofs of concept, we have successfully assembled up to 16 transcriptional units of various pigmentation genes in both operon and multigene arrangements. Taken together, Mobius Assembly delivers enhanced versatility and efficiency in DNA assembly, facilitating improved standardization and automation.

From schooling to shoaling: patterns of collective motion in zebrafish (Danio rerio.

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Noam Miller

Full Text Available Animal groups on the move can take different configurations. For example, groups of fish can either be 'shoals' or 'schools': shoals are simply aggregations of individuals; schools are shoals exhibiting polarized, synchronized motion. Here we demonstrate that polarization distributions of groups of zebrafish (Danio rerio are bimodal, showing two distinct modes of collective motion corresponding to the definitions of shoaling and schooling. Other features of the group's motion also vary consistently between the two modes: zebrafish schools are faster and less dense than zebrafish shoals. Habituation to an environment can also alter the proportion of time zebrafish groups spend schooling or shoaling. Models of collective motion suggest that the degree and stability of group polarization increases with the group's density. Examining zebrafish groups of different sizes from 5 to 50, we show that larger groups are less polarized than smaller groups. Decreased fearfulness in larger groups may function similarly to habituation, causing them to spend more time shoaling than schooling, contrary to most models' predictions.

Graph theoretical model of a sensorimotor connectome in zebrafish.

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Stobb, Michael; Peterson, Joshua M; Mazzag, Borbala; Gahtan, Ethan

2012-01-01

Mapping the detailed connectivity patterns (connectomes) of neural circuits is a central goal of neuroscience. The best quantitative approach to analyzing connectome data is still unclear but graph theory has been used with success. We present a graph theoretical model of the posterior lateral line sensorimotor pathway in zebrafish. The model includes 2,616 neurons and 167,114 synaptic connections. Model neurons represent known cell types in zebrafish larvae, and connections were set stochastically following rules based on biological literature. Thus, our model is a uniquely detailed computational representation of a vertebrate connectome. The connectome has low overall connection density, with 2.45% of all possible connections, a value within the physiological range. We used graph theoretical tools to compare the zebrafish connectome graph to small-world, random and structured random graphs of the same size. For each type of graph, 100 randomly generated instantiations were considered. Degree distribution (the number of connections per neuron) varied more in the zebrafish graph than in same size graphs with less biological detail. There was high local clustering and a short average path length between nodes, implying a small-world structure similar to other neural connectomes and complex networks. The graph was found not to be scale-free, in agreement with some other neural connectomes. An experimental lesion was performed that targeted three model brain neurons, including the Mauthner neuron, known to control fast escape turns. The lesion decreased the number of short paths between sensory and motor neurons analogous to the behavioral effects of the same lesion in zebrafish. This model is expandable and can be used to organize and interpret a growing database of information on the zebrafish connectome.

Low-cost embedded systems for democratizing ocean sensor technology in the coastal zone

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Glazer, B. T.; Lio, H. I.

2017-12-01

Environmental sciences suffer from undersampling. Enabling sustained and unattended data collection in the coastal zone typically involves expensive instrumentation and infrastructure deployed as cabled observatories or moorings with little flexibility in deployment location following initial installation. High costs of commercially-available or custom instruments have limited the number of sensor sites that can be targeted by academic researchers, and have also limited engagement with the public. We have developed a novel, low-cost, open-source sensor and software platform to enable wireless data transfer of biogeochemical sensors in the coastal zone. The platform is centered upon widely available, low-cost, single board computers and microcontrollers. We have used a blend of on-hand research-grade sensors and low-cost open-source electronics that can be assembled by tech-savvy non-engineers. Robust, open-source code that remains customizable for specific miniNode configurations can match a specific site's measurement needs, depending on the scientific research priorities. We have demonstrated prototype capabilities and versatility through lab testing and field deployments of multiple sensor nodes with multiple sensor inputs, all of which are streaming near-real-time data from Kaneohe Bay over wireless RF links to a shore-based base station.

Design of a Low-cost Oil Spill Tracking Buoy

Science.gov (United States)

Zhao, Y.; Hu, X.; Yu, F.; Dong, S.; Chen, G.

2017-12-01

As the rapid development of oil exploitation and transportation, oil spill accidents, such as Prestige oil spill, Gulf of Mexico oil spill accident and so on, happened frequently in recent years which would result in long-term damage to the environment and human life. It would be helpful for rescue operation if we can locate the oil slick diffusion area in real time. Equipped with GNSS system, current tracking buoys(CTB), such as Lagrangian drifting buoy, Surface Velocity Program (SVP) drifter, iSLDMB (Iridium self locating datum marker buoy) and Argosphere buoy, have been used as oil tracking buoy in oil slick observation and as validation tools for oil spill simulation. However, surface wind could affect the movement of oil slick, which couldn't be reflected by CTB, thus the oil spill tracking performance is limited. Here, we proposed an novel oil spill tracking buoy (OSTB) which has a low cost of less than $140 and is equipped with Beidou positioning module and sails to track oil slick. Based on hydrodynamic equilibrium model and ocean dynamic analysis, the wind sails and water sails are designed to be adjustable according to different marine conditions to improve tracking efficiency. Quick release device is designed to assure easy deployment from air or ship. Sea experiment was carried out in Jiaozhou Bay, Northern China. OSTB, SVP, iSLDMB, Argosphere buoy and a piece of oil-simulated rubber sheet were deployed at the same time. Meanwhile, oil spill simulation model GNOME (general NOAA operational modeling environment) was configured with the wind and current field, which were collected by an unmanned surface vehicle (USV) mounted with acoustic Doppler current profilers (ADCP) and wind speed and direction sensors. Experimental results show that the OSTB has better relevance with rubber sheet and GNOME simulation results, which validate the oil tracking ability of OSTB. With low cost and easy deployment, OSTB provides an effective way for oil spill numerical

ZeBase: an open-source relational database for zebrafish laboratories.

Science.gov (United States)

Hensley, Monica R; Hassenplug, Eric; McPhail, Rodney; Leung, Yuk Fai

2012-03-01

Abstract ZeBase is an open-source relational database for zebrafish inventory. It is designed for the recording of genetic, breeding, and survival information of fish lines maintained in a single- or multi-laboratory environment. Users can easily access ZeBase through standard web-browsers anywhere on a network. Convenient search and reporting functions are available to facilitate routine inventory work; such functions can also be automated by simple scripting. Optional barcode generation and scanning are also built-in for easy access to the information related to any fish. Further information of the database and an example implementation can be found at http://zebase.bio.purdue.edu.

High Speed, Low Cost Fabrication of Gas Diffusion Electrodes for Membrane Electrode Assemblies

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DeCastro, Emory S.; Tsou, Yu-Min; Liu, Zhenyu

2013-09-20

Fabrication of membrane electrode assemblies (MEAs) depends on creating inks or pastes of catalyst and binder, and applying this suspension to either the membrane (catalyst coated membrane) or gas diffusion media (gas diffusion electrode) and respectively laminating either gas diffusion media or gas diffusion electrodes (GDEs) to the membrane. One barrier to cost effective fabrication for either of these approaches is the development of stable and consistent suspensions. This program investigated the fundamental forces that destabilize the suspensions and developed innovative approaches to create new, highly stable formulations. These more concentrated formulations needed fewer application passes, could be coated over longer and wider substrates, and resulted in significantly lower coating defects. In March of 2012 BASF Fuel Cell released a new high temperature product based on these advances, whereby our customers received higher performing, more uniform MEAs resulting in higher stack build yields. Furthermore, these new materials resulted in an “instant” increase in capacity due to higher product yields and material throughput. Although not part of the original scope of this program, these new formulations have also led us to materials that demonstrate equivalent performance with 30% less precious metal in the anode. This program has achieved two key milestones in DOE’s Manufacturing R&D program: demonstration of processes for direct coating of electrodes and continuous in-line measurement for component fabrication.

Zebrafish as a visual and dynamic model to study the transport of nanosized drug delivery systems across the biological barriers.

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Li, Ye; Miao, Xiaoqing; Chen, Tongkai; Yi, Xiang; Wang, Ruibing; Zhao, Haitao; Lee, Simon Ming-Yuen; Wang, Xueqing; Zheng, Ying

2017-08-01

With the wide application of nanotechnology to drug delivery systems, a simple, dynamic and visual in vivo model for high-throughput screening of novel formulations with fluorescence markers across biological barriers is desperately needed. In vitro cell culture models have been widely used, although they are far from a complimentary in vivo system. Mammalian animal models are common predictive models to study transport, but they are costly and time consuming. Zebrafish (Danio rerio), a small vertebrate model, have the potential to be developed as an "intermediate" model for quick evaluations. Based on our previously established coumarin 6 nanocrystals (C6-NCs), which have two different sizes, the present study investigates the transportation of C6-NCs across four biological barriers, including the chorion, blood brain barrier (BBB), blood retinal barrier (BRB) and gastrointestinal (GI) barrier, using zebrafish embryos and larvae as in vivo models. The biodistribution and elimination of C6 from different organs were quantified in adult zebrafish. The results showed that compared to 200nm C6-NCs, 70nm C6-NCs showed better permeability across these biological barriers. A FRET study suggested that intact C6-NCs together with the free dissolved form of C6 were absorbed into the larval zebrafish. More C6 was accumulated in different organs after incubation with small sized NCs via lipid raft-mediated endocytosis in adult zebrafish, which is consistent with the findings from in vitro cell monolayers and the zebrafish larvae model. C6-NCs could be gradually eliminated in each organ over time. This study demonstrated the successful application of zebrafish as a simple and dynamic model to simultaneously assess the transport of nanosized drug delivery systems across several biological barriers and biodistribution in different organs, especially in the brain, which could be used for central nervous system (CNS) drug and delivery system screening. Copyright © 2017 Elsevier B

Fish from Head to Tail: The 9th European Zebrafish Meeting in Oslo.

Science.gov (United States)

Griffiths, Gareth; Müller, Ferenc; Ledin, Johan; Patton, E Elizabeth; Gjøen, Tor; Lobert, Viola Hélène; Winther-Larsen, Hanne Cecilie; Mullins, Mary; Joly, Jean-Stephane; Weltzien, Finn-Arne; Press, Charles McLean; Aleström, Peter

2016-04-01

The 9th European Zebrafish Meeting took place recently in Oslo (June 28-July 2, 2015). A total of 650 participants came to hear the latest research news focused on the zebrafish, Danio rerio, and to its distant evolutionary relative medaka, Oryzias latipes. The packed program included keynote and plenary talks, short oral presentations and poster sessions, workshops, and strategic discussions. The meeting was a great success and revealed dramatically how important the zebrafish in particular has become as a model system for topics, such as developmental biology, functional genomics, biomedicine, toxicology, and drug development. A new emphasis was given to its potential as a model for aquaculture, a topic of great economic interest to the host country Norway and for the future global food supply in general. Zebrafish husbandry as well as its use in teaching were also covered in separate workshops. As has become a tradition in these meetings, there was a well-attended Wellcome Trust Sanger Institute and ZFIN workshop focused on Zebrafish Genome Resources on the first day. The full EZM 2015 program with abstracts can be read and downloaded from the EZM 2015 Web site zebrafish2015.org .

Cyp1a reporter zebrafish reveals target tissues for dioxin

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Kim, Kun-Hee [Department of Biomedical Sciences, Chonnam National University Medical School, Gwangju (Korea, Republic of); Department of Microbiology, Chonnam National University Medical School, Gwangju (Korea, Republic of); Park, Hye-Jeong [Department of Biomedical Sciences, Chonnam National University Medical School, Gwangju (Korea, Republic of); Kim, Jin Hee [Department of Biomedical Sciences, Chonnam National University Medical School, Gwangju (Korea, Republic of); Department of Microbiology, Chonnam National University Medical School, Gwangju (Korea, Republic of); Kim, Suhyun [Graduate School of Medicine, Korea University, Ansan (Korea, Republic of); Williams, Darren R. [New Drug Targets Laboratory, School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju (Korea, Republic of); Kim, Myeong-Kyu [Department of Neurology, Chonnam National University Medical School, Gwangju (Korea, Republic of); Jung, Young Do [Department of Biochemistry, Chonnam National University Medical School, Gwangju (Korea, Republic of); Teraoka, Hiroki [School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu (Japan); Park, Hae-Chul [Graduate School of Medicine, Korea University, Ansan (Korea, Republic of); Choy, Hyon E., E-mail: hyonchoy@chonnam.ac.kr [Department of Microbiology, Chonnam National University Medical School, Gwangju (Korea, Republic of); Shin, Boo Ahn, E-mail: bashin@chonnam.ac.kr [Department of Microbiology, Chonnam National University Medical School, Gwangju (Korea, Republic of); Choi, Seok-Yong, E-mail: zebrafish@chonnam.ac.kr [Department of Biomedical Sciences, Chonnam National University Medical School, Gwangju (Korea, Republic of); School of Biological Sciences and Technology, Chonnam National University, Gwangju (Korea, Republic of)

2013-06-15

Highlights: •2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is the most toxic anthropogenic substance ever identified. •Transgenic cyp1a reporter zebrafish reveals target tissues for TCDD. •The retinal bipolar cells, otic vesicle, lateral line, pancreas, cloaca and pectoral fin bud are novel targets in zebrafish for TCDD. •Our findings will further understanding of human health risks by TCDD. -- Abstract: 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is the unintentional byproduct of various industrial processes, is classified as human carcinogen and could disrupt reproductive, developmental and endocrine systems. Induction of cyp1a1 is used as an indicator of TCDD exposure. We sought to determine tissues that are vulnerable to TCDD toxicity using a transgenic zebrafish (Danio rerio) model. We inserted a nuclear enhanced green fluorescent protein gene (EGFP) into the start codon of a zebrafish cyp1a gene in a fosmid clone using DNA recombineering. The resulting recombineered fosmid was then used to generate cyp1a reporter zebrafish, embryos of which were exposed to TCDD. Expression pattern of EGFP in the reporter zebrafish mirrored that of endogenous cyp1a mRNA. In addition, exposure of the embryos to TCDD at as low as 10 pM for 72 h, which does not elicit morphological abnormalities of embryos, markedly increased GFP expression. Furthermore, the reporter embryos responded to other AhR ligands as well. Exposure of the embryos to TCDD revealed previously reported (the cardiovascular system, liver, pancreas, kidney, swim bladder and skin) and unreported target tissues (retinal bipolar cells, otic vesicle, lateral line, cloaca and pectoral fin bud) for TCDD. Transgenic cyp1a reporter zebrafish we have developed can further understanding of ecotoxicological relevance and human health risks by TCDD. In addition, they could be used to identify agonists of AhR and antidotes to TCDD toxicity.

Low-cost inertial measurement unit.

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Deyle, Travis Jay

2005-03-01

Sandia National Laboratories performs many expensive tests using inertial measurement units (IMUs)--systems that use accelerometers, gyroscopes, and other sensors to measure flight dynamics in three dimensions. For the purpose of this report, the metrics used to evaluate an IMU are cost, size, performance, resolution, upgradeability and testing. The cost of a precision IMU is very high and can cost hundreds of thousands of dollars. Thus the goals and results of this project are as follows: (1) Examine the data flow in an IMU and determine a generic IMU design. (2) Discuss a high cost IMU implementation and its theoretically achievable results. (3) Discuss design modifications that would save money for suited applications. (4) Design and implement a low cost IMU and discuss its theoretically achievable results. (5) Test the low cost IMU and compare theoretical results with empirical results. (6) Construct a more streamlined printed circuit board design reducing noise, increasing capabilities, and constructing a self-contained unit. Using these results, we can compare a high cost IMU versus a low cost IMU using the metrics from above. Further, we can examine and suggest situations where a low cost IMU could be used instead of a high cost IMU for saving cost, size, or both.

Low-Cost, Rapidly Responsive, Controllable, and Reversible Photochromic Hydrogel for Display and Storage.

Science.gov (United States)

Yang, Yongqi; Guan, Lin; Gao, Guanghui

2018-04-25

Traditional optoelectronic devices without stretchable performance could be limited for substrates with irregular shape. Therefore, it is urgent to explore a new generation of flexible, stretchable, and low-cost intelligent vehicles as visual display and storage devices, such as hydrogels. In the investigation, a novel photochromic hydrogel was developed by introducing the negatively charged ammonium molybdate as a photochromic unit into polyacrylamide via ionic and covalent cross-linking. The hydrogel exhibited excellent properties of low cost, easy preparation, stretchable deformation, fatigue resistance, high transparency, and second-order response to external signals. Moreover, the photochromic and fading process of hydrogels could be precisely controlled and repeated under the irradiation of UV light and exposure of oxygen at different time and temperature. The photochromic hydrogel could be considered applied for artificial intelligence system, wearable healthcare device, and flexible memory device. Therefore, the strategy for designing a soft photochromic material would open a new direction to manufacture flexible and stretchable devices.

Establishing zebrafish as a novel exercise model: swimming economy, swimming-enhanced growth and muscle growth marker gene expression.

Directory of Open Access Journals (Sweden)

Arjan P Palstra

Full Text Available BACKGROUND: Zebrafish has been largely accepted as a vertebrate multidisciplinary model but its usefulness as a model for exercise physiology has been hampered by the scarce knowledge on its swimming economy, optimal swimming speeds and cost of transport. Therefore, we have performed individual and group-wise swimming experiments to quantify swimming economy and to demonstrate the exercise effects on growth in adult zebrafish. METHODOLOGY/PRINCIPAL FINDINGS: Individual zebrafish (n = 10 were able to swim at a critical swimming speed (U(crit of 0.548±0.007 m s(-1 or 18.0 standard body lengths (BL s(-1. The optimal swimming speed (U(opt at which energetic efficiency is highest was 0.396±0.019 m s(-1 (13.0 BL s(-1 corresponding to 72.26±0.29% of U(crit. The cost of transport at optimal swimming speed (COT(opt was 25.23±4.03 µmol g(-1 m(-1. A group-wise experiment was conducted with zebrafish (n = 83 swimming at U(opt for 6 h day(-1 for 5 days week(-1 for 4 weeks vs. zebrafish (n = 84 that rested during this period. Swimming zebrafish increased their total body length by 5.6% and body weight by 41.1% as compared to resting fish. For the first time, a highly significant exercise-induced growth is demonstrated in adult zebrafish. Expression analysis of a set of muscle growth marker genes revealed clear regulatory roles in relation to swimming-enhanced growth for genes such as growth hormone receptor b (ghrb, insulin-like growth factor 1 receptor a (igf1ra, troponin C (stnnc, slow myosin heavy chain 1 (smyhc1, troponin I2 (tnni2, myosin heavy polypeptide 2 (myhz2 and myostatin (mstnb. CONCLUSIONS/SIGNIFICANCE: From the results of our study we can conclude that zebrafish can be used as an exercise model for enhanced growth, with implications in basic, biomedical and applied sciences, such as aquaculture.

Endocrine disruption and reproduction impairment in zebrafish after long-term exposure to DE-71.

Science.gov (United States)

Yu, Liqin; Liu, Chunsheng; Chen, Qi; Zhou, Bingsheng

2014-06-01

The objective of the present study was to investigate the impact of polybrominated diphenyl ethers (PBDEs) on fish reproduction over 2 generations. Zebrafish (Danio rerio) embryos (F0) were exposed to low concentrations (3 µg/L, 10 µg/L, and 30 µg/L) of the PBDE mixture DE-71 until they were sexually mature, and steroid hormone production, expression of genes involved in steroidogenesis, gonadal development, and gamete characteristics were examined. Exposure of female zebrafish to DE-71 resulted in lower estradiol production and downregulation of cytochrome P450 aromatase mRNA. In males, exposure to DE-71 resulted in greater testosterone production and greater cytochrome P450 c17 α-hydroxylase,17,20-lase mRNA expression. Moreover, hepatic vitellogenin mRNA and estrogenic receptor β gene transcription were downregulated in females and males. Expression of the follicle-stimulating hormone β gene in the pituitary was upregulated, and the expression of luteinizing hormone β was downregulated in both sexes. Histological examination showed inhibition of oocyte maturation in females and retarded spermiation in males. The average number of eggs (F1) produced was also reduced. Additionally, exposure of F0 embryos to DE-71 did not result in developmental toxicity, whereas delayed hatching, reduced survival, and decreased growth were observed in the F1 embryos derived from parent fish exposed to DE-71. Therefore, long-term exposure to low concentrations of PBDEs in zebrafish could cause reproductive impairment, suggesting that PBDEs might have significant adverse effects on fish population in the highly PBDEs-contaminated aquatic environment. © 2014 SETAC.

Comparison of Different Assembling Techniques Regarding Cost, Durability, and Ecology - A Survey of Multi-layer Wooden Panel Assembly Load-Bearing Construction Elements

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Dietrich Buck

2015-10-01

Full Text Available Wood is a pure, sustainable, renewable material. The increasing use of wood for construction can improve its sustainability. There are various techniques to assemble multi-layer wooden panels into prefabricated, load-bearing construction elements. However, comparative market and economy studies are still scarce. In this study, the following assembling techniques were compared: laminating, nailing, stapling, screwing, stress laminating, doweling, dovetailing, and wood welding. The production costs, durability, and ecological considerations were presented. This study was based on reviews of published works and information gathered from 27 leading wood product manufacturing companies in six European countries. The study shows that the various techniques of assembling multi-layer wooden construction panel elements are very different. Cross laminated timber (CLT exhibited the best results in terms of cost and durability. With regard to ecological concerns, dovetailing is the best. Taking into account both durability and ecological considerations, wooden screw-doweling is the best. These alternatives give manufacturers some freedom of choice regarding the visibility of surfaces and the efficient use of lower-quality timber. CLT is the most cost-effective, is not patented, and is a well-established option on the market today.

Low-cost zinc-plated photoanode for fabric-type dye-sensitized solar cells

Energy Technology Data Exchange (ETDEWEB)

Kong, Lingfeng; Bao, Yunna; Guo, Wanwan; Cheng, Li; Du, Jun; Liu, Renlong [College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400030 (China); Wang, Yundong [Department of Chemical Engineering, Tsinghua University, State Key Lab of Chemical Engineering, Beijing 100084 (China); Fan, Xing, E-mail: foxcqdx@cqu.edu.cn [College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400030 (China); Tao, Changyuan [College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400030 (China)

2016-02-15

Graphical abstract: - Highlights: • Fabric-type flexible solar cells have been assembled on Zn-plated wires and meshes. • Metal Zn can improve the carriers transfer over the metal/ZnO nanoarrays interface. • A current increase by ∼6 mA/cm{sup 2} was realized by plating Zn on various metal substrates. • All-solid fabric-type DSSC was also assembled on Zn-plated metal wires. - Abstract: Fabric-type flexible solar cells have been recently proposed as a very promising power source for wearable electronics. To increase the photocurrent of fabric-type flexible solar cells, low-cost zinc-plated wire and mesh photoanodes are assembled for the first time through a mild wet process. Given the protection of the compact protection layer, the DSSC device could benefit from the low work function of Zn and self-repairing behavior on the Zn/ZnO interface. An evident current increase by ∼6 mA/cm{sup 2} could be observed after coating a layer of metal Zn on various metal substrates, such as traditional stainless steel wire. Given the self-repairing behavior on Zn/ZnO interface, the Zn layer can help to improve the interfacial carrier transfer, leading to better photovoltaic performance, for both liquid-type and solid-type cells.

Low-cost zinc-plated photoanode for fabric-type dye-sensitized solar cells

International Nuclear Information System (INIS)

Kong, Lingfeng; Bao, Yunna; Guo, Wanwan; Cheng, Li; Du, Jun; Liu, Renlong; Wang, Yundong; Fan, Xing; Tao, Changyuan

2016-01-01

Graphical abstract: - Highlights: • Fabric-type flexible solar cells have been assembled on Zn-plated wires and meshes. • Metal Zn can improve the carriers transfer over the metal/ZnO nanoarrays interface. • A current increase by ∼6 mA/cm"2 was realized by plating Zn on various metal substrates. • All-solid fabric-type DSSC was also assembled on Zn-plated metal wires. - Abstract: Fabric-type flexible solar cells have been recently proposed as a very promising power source for wearable electronics. To increase the photocurrent of fabric-type flexible solar cells, low-cost zinc-plated wire and mesh photoanodes are assembled for the first time through a mild wet process. Given the protection of the compact protection layer, the DSSC device could benefit from the low work function of Zn and self-repairing behavior on the Zn/ZnO interface. An evident current increase by ∼6 mA/cm"2 could be observed after coating a layer of metal Zn on various metal substrates, such as traditional stainless steel wire. Given the self-repairing behavior on Zn/ZnO interface, the Zn layer can help to improve the interfacial carrier transfer, leading to better photovoltaic performance, for both liquid-type and solid-type cells.

Virtual Reality and Haptics for Product Assembly

Directory of Open Access Journals (Sweden)

Maria Teresa Restivo

2012-01-01

Full Text Available Haptics can significantly enhance the user's sense of immersion and interactivity. An industrial application of virtual reality and haptics for product assembly is described in this paper, which provides a new and low-cost approach for product assembly design, assembly task planning and assembly operation training. A demonstration of the system with haptics device interaction was available at the session of exp.at'11.

Zebrafish as an In Vivo Model to Assess Epigenetic Effects of Ionizing Radiation

Directory of Open Access Journals (Sweden)

Eva Yi Kong

2016-12-01

Full Text Available Exposure to ionizing radiations (IRs is ubiquitous in our environment and can be categorized into “targeted” effects and “non-targeted” effects. In addition to inducing deoxyribonucleic acid (DNA damage, IR exposure leads to epigenetic alterations that do not alter DNA sequence. Using an appropriate model to study the biological effects of radiation is crucial to better understand IR responses as well as to develop new strategies to alleviate exposure to IR. Zebrafish, Danio rerio, is a scientific model organism that has yielded scientific advances in several fields and recent studies show the usefulness of this vertebrate model in radiation biology. This review briefly describes both “targeted” and “non-targeted” effects, describes the findings in radiation biology using zebrafish as a model and highlights the potential of zebrafish to assess the epigenetic effects of IR, including DNA methylation, histone modifications and miRNA expression. Other in vivo models are included to compare observations made with zebrafish, or to illustrate the feasibility of in vivo models when the use of zebrafish was unavailable. Finally, tools to study epigenetic modifications in zebrafish, including changes in genome-wide DNA methylation, histone modifications and miRNA expression, are also described in this review.

Construction of a low cost wind energy generator; Construcao de um gerador de energia eolica de baixo custo

Energy Technology Data Exchange (ETDEWEB)

Almeida, Jonathan Penha de; Almeida, Silvio Carlos Anibal de [Universidade Federal do Rio de Janeiro (DEM/EP/UFRJ), RJ (Brazil). Escola Politecnica. Dept. de Engenharia Mecanica], Emails: jonathan_penha@poli.ufrj.br, silvioa@gmail.com

2010-07-01

This project presents a low cost wind electric power generator constituted of cheap and easy access materials. The necessary materials are presented for it construction and the expected efficiency, having as reference the city of Fernando de Noronha, Brazil. The elaboration of the generator was initially developed as alternative energy source during blackout.

An innovative design of small low head hydropower units for low cost decentralized production

International Nuclear Information System (INIS)

Holmen, E.; Dennehy, T.

1991-01-01

Design allowing turbine operation at heads as low as 1m and operating at a rotational speed of 500 RPM at a flow of 2.6m 3 /s and a runner diameter of 700 mm. This eliminates the need for a gear box and helps in achieving efficiency of 60% in the case of a 21 kW installation at a 1m head site and 85% with a 69 kW 3.2m head site. Present turbine designs for such low head sites are very expensive to produce and have a low efficiency. The design uses an all plastic waterway, guide vane assembly and reinforced plastic runner blades. There will be a short pay-back period, for example 4.5 years in the case of a 21 kW unit and 2.0 years in case of the 69 kW unit. These payback periods assume a cost per kW of 0.00 ECU. Design is attractive for decentralized production. 3 figs

Graph theoretical model of a sensorimotor connectome in zebrafish.

Directory of Open Access Journals (Sweden)

Michael Stobb

Full Text Available Mapping the detailed connectivity patterns (connectomes of neural circuits is a central goal of neuroscience. The best quantitative approach to analyzing connectome data is still unclear but graph theory has been used with success. We present a graph theoretical model of the posterior lateral line sensorimotor pathway in zebrafish. The model includes 2,616 neurons and 167,114 synaptic connections. Model neurons represent known cell types in zebrafish larvae, and connections were set stochastically following rules based on biological literature. Thus, our model is a uniquely detailed computational representation of a vertebrate connectome. The connectome has low overall connection density, with 2.45% of all possible connections, a value within the physiological range. We used graph theoretical tools to compare the zebrafish connectome graph to small-world, random and structured random graphs of the same size. For each type of graph, 100 randomly generated instantiations were considered. Degree distribution (the number of connections per neuron varied more in the zebrafish graph than in same size graphs with less biological detail. There was high local clustering and a short average path length between nodes, implying a small-world structure similar to other neural connectomes and complex networks. The graph was found not to be scale-free, in agreement with some other neural connectomes. An experimental lesion was performed that targeted three model brain neurons, including the Mauthner neuron, known to control fast escape turns. The lesion decreased the number of short paths between sensory and motor neurons analogous to the behavioral effects of the same lesion in zebrafish. This model is expandable and can be used to organize and interpret a growing database of information on the zebrafish connectome.

Process-based costing.

Science.gov (United States)

Lee, Robert H; Bott, Marjorie J; Forbes, Sarah; Redford, Linda; Swagerty, Daniel L; Taunton, Roma Lee

2003-01-01

Understanding how quality improvement affects costs is important. Unfortunately, low-cost, reliable ways of measuring direct costs are scarce. This article builds on the principles of process improvement to develop a costing strategy that meets both criteria. Process-based costing has 4 steps: developing a flowchart, estimating resource use, valuing resources, and calculating direct costs. To illustrate the technique, this article uses it to cost the care planning process in 3 long-term care facilities. We conclude that process-based costing is easy to implement; generates reliable, valid data; and allows nursing managers to assess the costs of new or modified processes.

Imaging a seizure model in zebrafish with structured illumination light sheet microscopy

Science.gov (United States)

Liu, Yang; Dale, Savannah; Ball, Rebecca; VanLeuven, Ariel J.; Baraban, Scott; Sornborger, Andrew; Lauderdale, James D.; Kner, Peter

2018-02-01

Zebrafish are a promising vertebrate model for elucidating how neural circuits generate behavior under normal and pathological conditions. The Baraban group first demonstrated that zebrafish larvae are valuable for investigating seizure events and can be used as a model for epilepsy in humans. Because of their small size and transparency, zebrafish embryos are ideal for imaging seizure activity using calcium indicators. Light-sheet microscopy is well suited to capturing neural activity in zebrafish because it is capable of optical sectioning, high frame rates, and low excitation intensities. We describe work in our lab to use light-sheet microscopy for high-speed long-time imaging of neural activity in wildtype and mutant zebrafish to better understand the connectivity and activity of inhibitory neural networks when GABAergic signaling is altered in vivo. We show that, with light-sheet microscopy, neural activity can be recorded at 23 frames per second in twocolors for over 10 minutes allowing us to capture rare seizure events in mutants. We have further implemented structured illumination to increase resolution and contrast in the vertical and axial directions during high-speed imaging at an effective frame rate of over 7 frames per second.

Qualitative performance and economic analysis of low cost solar fish driers in Sub-Saharan Africa

Directory of Open Access Journals (Sweden)

Moshood Keke Mustapha

2014-04-01

Full Text Available Qualitative performance and economic analysis of five low cost solar driers were evaluated at the Zoology and Physics Laboratories of the University of Ilorin, Ilorin, Nigeria. The solar driers were constructed from mosquito net, plastic, aluminum and glass with black stone inserted in it. The driers were found to be better than the other driers because they are cheap, reliable, safe to use, easy to repair, well insulated, and cost effective. The solar driers are compact, efficient with drying of fish with lowest moisture content achieved within a few days and the dried products of good quality, with long shelf life, highly acceptable to consumers. The driers save man-hour, money, use renewable energy, with no operational or maintenance costs. The driers have a long life span, with net income to fisher folks very high and the payback time for the driers very low. The adoption of the driers will contribute to the economy of rural populace in the developing countries where there is no electricity and the challenges of deforestation are becoming prominent. The improved low cost solar driers will ensure food safety and security and assist in combating climate change resulting from burning of wood and fossil fuel.

Procedures for parametric studies of costs of superconducting toroidal test assemblies

International Nuclear Information System (INIS)

Thompson, P.B.

1976-05-01

A cost scaling procedure, based on a detailed reference conceptual design, has been developed to determine the effects of variations in the characteristic parameters of superconducting toroidal field coils on project costs. The primary purpose was to provide reasonably simple rational formulae for obtaining approximate costs of a complete installation, focusing on the trends and sensitivities of costs to changes in various parameters such as field strength, coil size, number of coils, and current density rather than establishing absolute costs. No results are included here because early studies applying these procedures are no longer pertinent to the present Superconducting Magnet Development Program. However, planning for the Large Coil Project and the preliminary conceptual design of the Technology Test Assembly with Plasma have employed the techniques described and results will be reported in the appropriate project documents

ALARA (As Low As Reasonable Achievable) procedure applied to fuel assembly fabrication with enriched reprocessing uranium (ERU)

International Nuclear Information System (INIS)

Guimaraes, Leonam dos Santos; Degrange, Jean Pierre

1998-01-01

The study introduced by this paper compose the first step to the implementation of ALARA (As Low As Reasonable Achievable) for a nuclear fuel assembly factory which one of its two production lines will be designed to work with Enriched Reprocessing Uranium (ERU). This step includes the reference situation analysis is based on previsional dosimetric evaluations for individual and collective exposures of each factory operator (117 in total) working on 7 work stations, considering 6 annual production scenarios (10, 50 75, 100 and 150 ERU tons), which corresponds to an annual production of 600 tons (ERU plus enriched natural uranium ENU). The exposure indicators evolution, expressed in terms of collective dose, annual individual dose and radiological detrimental cost for workers, is also used in a complimentary way to guide the analysis. (author)

Quebec Trophoblastic Disease Registry: how to make an easy-to-use dynamic database.

Science.gov (United States)

Sauthier, Philippe; Breguet, Magali; Rozenholc, Alexandre; Sauthier, Michaël

2015-05-01

To create an easy-to-use dynamic database designed specifically for the Quebec Trophoblastic Disease Registry (RMTQ). It is now well established that much of the success in managing trophoblastic diseases comes from the development of national and regional reference centers. Computerized databases allow the optimal use of data stored in these centers. We have created an electronic data registration system by producing a database using FileMaker Pro 12. It uses 11 external tables associated with a unique identification number for each patient. Each table allows specific data to be recorded, incorporating demographics, diagnosis, automated staging, laboratory values, pathological diagnosis, and imaging parameters. From January 1, 2009, to December 31, 2013, we used our database to register 311 patients with 380 diseases and have seen a 39.2% increase in registrations each year between 2009 and 2012. This database allows the automatic generation of semilogarithmic curves, which take into account β-hCG values as a function of time, complete with graphic markers for applied treatments (chemotherapy, radiotherapy, or surgery). It generates a summary sheet for a synthetic vision in real time. We have created, at a low cost, an easy-to-use database specific to trophoblastic diseases that dynamically integrates staging and monitoring. We propose a 10-step procedure for a successful trophoblastic database. It improves patient care, research, and education on trophoblastic diseases in Quebec and leads to an opportunity for collaboration on a national Canadian registry.

Easy approach to assembling a biomimetic color film with tunable structural colors.

Science.gov (United States)

Wang, Wentao; Tang, Bingtao; Ma, Wei; Zhang, Jian; Ju, Benzhi; Zhang, Shufen

2015-06-01

The self-assembly of silica microspheres into a close-packed array is a simple method of fabricating three-dimensional photonic crystal structural color films. However, the color is very dull because of the interferences of scattering and background light. In this study, we added a small quantity of surface-modified carbon black (CB) to the system of colloidal silica in n-propanol. The use of n-propanol as a dispersant is beneficial to the rapid development of photonic crystal films during the process of dip-coating. The doping of CB into silica microspheres can absorb background and scattering light, resulting in vivid structural colors.

Exposure to a PBDE/OH-BDE mixture alters juvenile zebrafish (Danio rerio) development.

Science.gov (United States)

Macaulay, Laura J; Chernick, Melissa; Chen, Albert; Hinton, David E; Bailey, Jordan M; Kullman, Seth W; Levin, Edward D; Stapleton, Heather M

2017-01-01

Polybrominated diphenyl ethers (PBDEs) and their metabolites (e.g., hydroxylated BDEs [OH-BDEs]) are contaminants frequently detected together in human tissues and are structurally similar to thyroid hormones. Thyroid hormones partially mediate metamorphic transitions between life stages in zebrafish, making this a critical developmental window that may be vulnerable to chemicals disrupting thyroid signaling. In the present study, zebrafish were exposed to 6-OH-BDE-47 (30 nM; 15 μg/L) alone, or to a low-dose (30 μg/L) or high-dose (600 μg/L) mixture of PentaBDEs, 6-OH-BDE-47 (0.5-6 μg/L), and 2,4,6-tribromophenol (5-100 μg/L) during juvenile development (9-23 d postfertilization) and evaluated for developmental endpoints mediated by thyroid hormone signaling. Fish were sampled at 3 time points and examined for developmental and skeletal morphology, apical thyroid and skeletal gene markers, and modifications in swimming behavior (as adults). Exposure to the high-dose mixture resulted in >85% mortality within 1 wk of exposure, despite being below reported acute toxicity thresholds for individual congeners. The low-dose mixture and 6-OH-BDE-47 groups exhibited reductions in body length and delayed maturation, specifically relating to swim bladder, fin, and pigmentation development. Reduced skeletal ossification was also observed in 6-OH-BDE-47-treated fish. Assessment of thyroid and osteochondral gene regulatory networks demonstrated significantly increased expression of genes that regulate skeletal development and thyroid hormones. Overall, these results indicate that exposures to PBDE/OH-BDE mixtures adversely impact zebrafish maturation during metamorphosis. Environ Toxicol Chem 2017;36:36-48. © 2016 SETAC. © 2016 SETAC.

Spatial pattern of cell geometry and cell-division orientation in zebrafish lens epithelium

Directory of Open Access Journals (Sweden)

Toshiaki Mochizuki

2014-09-01

Full Text Available Cell proliferation is a key regulator of tissue morphogenesis. We examined cell proliferation and cell division in zebrafish lens epithelium by visualizing cell-cycle phases and nuclear positions, using fluorescent-labeled geminin and histone proteins. Proliferation was low in the anterior region of lens epithelium and higher in the marginal zone anterior to the equator, suggesting that the proliferation zone, called the germinative zone, is formed in zebrafish lens. Interestingly, cell-division orientation was biased longitudinally in the anterior region, shifted from longitudinal to circumferential along the anterior–posterior axis of lens sphere, and was biased circumferentially in the peripheral region. These data suggest that cell-division orientation is spatially regulated in zebrafish lens epithelium. The Hertwig rule indicates that cells tend to divide along their long axes. Orientation of long axes and cell division were biased similarly in zebrafish lens epithelium, suggesting that cell geometry correlates with cell-division orientation. A cell adhesion molecule, E-cadherin, is expressed in lens epithelium. In a zebrafish e-cadherin mutant, the long axes and cell-division orientation were shifted more longitudinally. These data suggest that E-cadherin is required for the spatial pattern of cell geometry and cell-division orientation in zebrafish lens epithelium.

In Vivo Cardiotoxicity Induced by Sodium Aescinate in Zebrafish Larvae

Directory of Open Access Journals (Sweden)

Jinfeng Liang

2016-02-01

Full Text Available Sodium aescinate (SA is a widely-applied triterpene saponin product derived from horse chestnut seeds, possessing vasoactive and organ-protective activities with oral or injection administration in the clinic. To date, no toxicity or adverse events in SA have been reported, by using routine models (in vivo or in vitro, which are insufficient to predict all aspects of its pharmacological and toxicological actions. In this study, taking advantage of transparent zebrafish larvae (Danio rerio, we evaluated cardiovascular toxicity of SA at doses of 1/10 MNLC, 1/3 MNLC, MNLC and LC10 by yolk sac microinjection. The qualitative and quantitative cardiotoxicity in zebrafish was assessed at 48 h post-SA treatment, using specific phenotypic endpoints: heart rate, heart rhythm, heart malformation, pericardial edema, circulation abnormalities, thrombosis and hemorrhage. The results showed that SA at 1/10 MNLC and above doses could induce obvious cardiac and pericardial malformations, whilst 1/3 MNLC and above doses could induce significant cardiac malfunctions (heart rate and circulation decrease/absence, as compared to untreated or vehicle-treated control groups. Such cardiotoxic manifestations occurred in more than 50% to 100% of all zebrafish treated with SA at MNLC and LC10. Our findings have uncovered the potential cardiotoxicity of SA for the first time, suggesting more attention to the risk of its clinical application. Such a time- and cost-saving zebrafish cardiotoxicity assay is very valid and reliable for rapid prediction of compound toxicity during drug research and development.

Assembly and patterning of the vascular network of the vertebrate hindbrain

OpenAIRE

Fujita, Misato; Cha, Young R.; Pham, Van N.; Sakurai, Atsuko; Roman, Beth L.; Gutkind, J. Silvio; Weinstein, Brant M.

2011-01-01

The cranial vasculature is essential for the survival and development of the central nervous system and is important in stroke and other brain pathologies. Cranial vessels form in a reproducible and evolutionarily conserved manner, but the process by which these vessels assemble and acquire their stereotypic patterning remains unclear. Here, we examine the stepwise assembly and patterning of the vascular network of the zebrafish hindbrain. The major artery supplying the hindbrain, the basilar...

The zebrafish reference genome sequence and its relationship to the human genome.

NARCIS (Netherlands)

Howe, K.; Clark, M.D.; Torroja, C.F.; Torrance, J.; Berthelot, C.; Muffato, M.; Collins, J.E.; Humphray, S.; McLaren, K.; Matthews, L.; McLaren, S.; Sealy, I.; Caccamo, M.; Churcher, C.; Scott, C.; Barrett, J.C.; Koch, R.; Rauch, G.J.; White, S.; Chow, W.; Kilian, B.; Quintais, L.T.; Guerra-Assuncao, J.A.; Zhou, Y.; Gu, Y.; Yen, J.; Vogel, J.H.; Eyre, T.; Redmond, S.; Banerjee, R.; Chi, J.; Fu, B.; Langley, E.; Maguire, S.F.; Laird, G.K.; Lloyd, D.; Kenyon, E.; Donaldson, S.; Sehra, H.; Almeida-King, J.; Loveland, J.; Trevanion, S.; Jones, M.; Quail, M.; Willey, D.; Hunt, A.; Burton, J.; Sims, S.; McLay, K.; Plumb, B.; Davis, J.; Clee, C.; Oliver, K.; Clark, R.; Riddle, C.; Elliot, D.; Threadgold, G.; Harden, G.; Ware, D.; Mortimore, B.; Kerry, G.; Heath, P.; Phillimore, B.; Tracey, A.; Corby, N.; Dunn, M.; Johnson, C.; Wood, J.; Clark, S.; Pelan, S.; Griffiths, G.; Smith, M.; Glithero, R.; Howden, P.; Barker, N.; Stevens, C.; Harley, J.; Holt, K.; Panagiotidis, G.; Lovell, J.; Beasley, H.; Henderson, C.; Gordon, D.; Auger, K.; Wright, D.; Collins, J.; Raisen, C.; Dyer, L.; Leung, K.; Robertson, L.; Ambridge, K.; Leongamornlert, D.; McGuire, S.; Gilderthorp, R.; Griffiths, C.; Manthravadi, D.; Nichol, S.; Barker, G.; Whitehead, S.; Kay, M.; Brown, J.; Murnane, C.; Gray, E.; Humphries, M.; Sycamore, N.; Barker, D.; Saunders, D.; Wallis, J.; Babbage, A.; Hammond, S.; Mashreghi-Mohammadi, M.; Barr, L.; Martin, S.; Wray, P.; Ellington, A.; Matthews, N.; Ellwood, M.; Woodmansey, R.; Clark, G.; Cooper, J.; Tromans, A.; Grafham, D.; Skuce, C.; Pandian, R.; Andrews, R.; Harrison, E.; Kimberley, A.; Garnett, J.; Fosker, N.; Hall, R.; Garner, P.; Kelly, D.; Bird, C.; Palmer, S.; Gehring, I.; Berger, A.; Dooley, C.M.; Ersan-Urun, Z.; Eser, C.; Geiger, H.; Geisler, M.; Karotki, L.; Kirn, A.; Konantz, J.; Konantz, M.; Oberlander, M.; Rudolph-Geiger, S.; Teucke, M.; Osoegawa, K.; Zhu, B.; rapp, A.; Widaa, S.; Langford, C.; Yang, F.; Carter, N.P.; Harrow, J.; Ning, Z.; Herrero, J.; Searle, S.M.; Enright, A.; Geisler, R.; Plasterk, R.H.A.; Lee, C.; Westerfield, M.; de Jong, P.J.; Zon, L.I.; Postlethwait, J.H.; Nusslein-Volhard, C.; Hubbard, T.J.; Roest Crollius, H.; Rogers, J.; Stemple, D.L.; Begum, S.; Lloyd, C.; Lanz, C.; Raddatz, G.; Schuster, S.C.

2013-01-01

Zebrafish have become a popular organism for the study of vertebrate gene function. The virtually transparent embryos of this species, and the ability to accelerate genetic studies by gene knockdown or overexpression, have led to the widespread use of zebrafish in the detailed investigation of

Laser capture microdissection of gonads from juvenile zebrafish

DEFF Research Database (Denmark)

Jørgensen, Anne; Nielsen, John; Morthorst, Jane Ebsen

2009-01-01

was adjusted and optimised to isolate juvenile zebrafish gonads. Results: The juvenile zebrafish gonad is not morphologically distinguishable when using dehydrated cryosections on membrane slides and a specific staining method is necessary to identify the gonads. The protocol setup in this study allows......Background: Investigating gonadal gene expression is important in attempting to elucidate the molecular mechanism of sex determination and differentiation in the model species zebrafish. However, the small size of juvenile zebrafish and correspondingly their gonads complicates this type...... of investigation. Furthermore, the lack of a genetic sex marker in juvenile zebrafish prevents pooling gonads from several individuals. The aim of this study was to establish a method to isolate the gonads from individual juvenile zebrafish allowing future investigations of gonadal gene expression during sex...

Microarray analysis in the zebrafish (Danio rerio) liver and telencephalon after exposure to low concentration of 17alpha-ethinylestradiol

Energy Technology Data Exchange (ETDEWEB)

Martyniuk, Christopher J. [Centre for Advanced Research in Environmental Genomics, 30 Marie Curie, Department of Biology, University of Ottawa, Ottawa, Ontario, K1N 6N5 (Canada); Gerrie, Emily R. [Centre for Advanced Research in Environmental Genomics, 30 Marie Curie, Department of Biology, University of Ottawa, Ottawa, Ontario, K1N 6N5 (Canada); Popesku, Jason T. [Centre for Advanced Research in Environmental Genomics, 30 Marie Curie, Department of Biology, University of Ottawa, Ottawa, Ontario, K1N 6N5 (Canada); Ekker, Marc [Centre for Advanced Research in Environmental Genomics, 30 Marie Curie, Department of Biology, University of Ottawa, Ottawa, Ontario, K1N 6N5 (Canada); Trudeau, Vance L. [Centre for Advanced Research in Environmental Genomics, 30 Marie Curie, Department of Biology, University of Ottawa, Ottawa, Ontario, K1N 6N5 (Canada)]. E-mail: trudeauv@uottawa.ca

2007-08-15

17alpha-ethinylestradiol (EE2) is detected in sewage effluent at concentrations that can disrupt normal reproductive function in fish. The objectives of this study were to identify novel genomic responses to EE2 exposure using microarray and real-time RT-PCR analysis in the liver and telencephalon of male zebrafish. Zebrafish were exposed to an environmentally relevant nominal concentration of 10 ng/L EE2 for a 21-day period. In the liver, common biomarkers for estrogenic exposure such as vitellogenin 1 and 3 (vtg1; vtg3), estrogen receptor alpha (esr1), and apolipoprotein A1 (apoA1) mRNA were identified by microarray analysis as being differentially regulated. Real-time RT-PCR confirmed that vtg1 was induced {approx}700-fold, vtg3 was induced {approx}100-fold and esr1 was induced {approx}20-fold. As determined by microarray analysis, ATPase Na+/K+ alpha 1a.4 (atp1a1a.4) and ATPase Na+/K+ beta 1a (atp1b1a) mRNA were down-regulated in the liver. Gene ontology (GO) analysis revealed that there were common biological processes and molecular functions regulated by EE2 in both tissues (e.g. electron transport and cell communication) but there were tissue specific changes in gene categories. For example, genes involved in protein metabolism, carbohydrate metabolism were down-regulated in the liver but were induced in the telencephalon. This study demonstrates that (1) tissues exhibit different gene responses to low EE2 exposure; (2) there are pronounced genomic effects in the liver and (3) multi-tissue gene profiling is needed to improve understanding of the effects of human pharmaceuticals on aquatic organisms.

Low-cost optical interconnect module for parallel optical data links

Science.gov (United States)

Noddings, Chad; Hirsch, Tom J.; Olla, M.; Spooner, C.; Yu, Jason J.

1995-04-01

We have designed, fabricated, and tested a prototype parallel ten-channel unidirectional optical data link. When scaled to production, we project that this technology will satisfy the following market penetration requirements: (1) up to 70 meters transmission distance, (2) at least 1 gigabyte/second data rate, and (3) 0.35 to 0.50 MByte/second volume selling price. These goals can be achieved by means of the assembly innovations described in this paper: a novel alignment method that is integrated with low-cost, few chip module packaging techniques, yielding high coupling and reducing the component count. Furthermore, high coupling efficiency increases projected reliability reducing the driver's power requirements.

Identification and characterization of zebrafish thrombocytes.

Science.gov (United States)

Jagadeeswaran, P; Sheehan, J P; Craig, F E; Troyer, D

1999-12-01

To analyse primary haemostasis in the zebrafish we have identified and characterized the zebrafish thrombocyte by morphologic, immunologic and functional approaches. Novel methods were developed for harvesting zebrafish blood with preservation of thrombocytes, and assaying whole blood adhesion/aggregation responses in microtitre plates. Light and electron microscopy of the thrombocyte illustrated morphological characteristics including the formation of aggregates, pseudopodia, and surface-connected vesicles analagous to the platelet canalicular system. Immunostaining with polyclonal antisera versus human platelet glycoproteins demonstrated the presence of glycoprotein Ib and IIb/IIIa-like complexes on the thrombocyte surface. Whole blood assays for adhesion/aggregation and ATP release showed ristocetin-induced adhesion without ATP release, and platelet agonist (collagen, arachidonic acid) induced aggregation with ATP release. Blood harvested from zebrafish treated with aspirin demonstrated inhibition of arachidonic acid induced aggregation and agonist induced ATP release, consistent with at least partial dependence on an intact cyclo oxygenase pathway. The combined morphologic immunologic and functional evidence suggest that the zebrafish thrombocyte is the haemostatic homologue of the mammalian platelet. Conservation of major haemostatic pathways involved in platelet function and coagulation suggests that the zebrafish is a relevant model for mammalian haemostasis and thrombosis.

Mutant human FUS Is ubiquitously mislocalized and generates persistent stress granules in primary cultured transgenic zebrafish cells.

Directory of Open Access Journals (Sweden)

Jamie Rae Acosta

Full Text Available FUS mutations can occur in familial amyotrophic lateral sclerosis (fALS, a neurodegenerative disease with cytoplasmic FUS inclusion bodies in motor neurons. To investigate FUS pathology, we generated transgenic zebrafish expressing GFP-tagged wild-type or fALS (R521C human FUS. Cell cultures were made from these zebrafish and the subcellular localization of human FUS and the generation of stress granule (SG inclusions examined in different cell types, including differentiated motor neurons. We demonstrate that mutant FUS is mislocalized from the nucleus to the cytosol to a similar extent in motor neurons and all other cell types. Both wild-type and R521C FUS localized to SGs in zebrafish cells, demonstrating an intrinsic ability of human FUS to accumulate in SGs irrespective of the presence of disease-associated mutations or specific cell type. However, elevation in relative cytosolic to nuclear FUS by the R521C mutation led to a significant increase in SG assembly and persistence within a sub population of vulnerable cells, although these cells were not selectively motor neurons.

Low-cost, highly transparent flexible low-e coating film to enable electrochromic windows with increased energy savings

Energy Technology Data Exchange (ETDEWEB)

Berland, Brian [ITN Energy Systems, Inc., Littleton, CO (United States); Hollingsworth, Russell [ITN Energy Systems, Inc., Littleton, CO (United States)

2015-03-31

Five Quads of energy are lost through windows annually in the U.S. Low-e coatings are increasingly employed to reduce the wasted energy. Most commonly, the low-e coating is an oxide material applied directly to the glass at high temperature. With over 100,000,000 existing homes, a retrofit product is crucial to achieve widespread energy savings. Low-e films, i.e. coatings on polymeric substrates, are now also available to meet this need. However, the traditional oxide materials and process is incompatible with low temperature plastics. Alternate high performing low-e films typically incorporate materials that limit visible transmission to 35% or less. Further, the cost is high. The objective of this award was to develop a retrofit, integrated low-e/electrochromic window film to dramatically reduce energy lost through windows. While field testing of state-of-the-art electrochromic (EC) windows show the energy savings are maximized if a low-e coating is used in conjunction with the EC, available low-e films have a low visible transmission (~70% or less) that limits the achievable clear state and therefore, appearance and energy savings potential. Comprehensive energy savings models were completed at Lawrence Berkeley National Lab (LBNL). A parametric approach was used to project energy usage for windows with a large range of low-e properties across all U.S. climate zones, without limiting the study to materials that had already been produced commercially or made in a lab. The model enables projection of energy savings for low-e films as well as integrated low-e/EC products. This project developed a novel low-e film, optimized for compatibility with EC windows, using low temperature, high deposition rate processes for the growth of low-e coatings on plastic films by microwave plasma enhanced chemical vapor deposition. Silica films with good density and optical properties were demonstrated at deposition rates as high as 130Å/sec. A simple bi-layer low-e stack of

Zebrafish models flex their muscles to shed light on muscular dystrophies.

Science.gov (United States)

Berger, Joachim; Currie, Peter D

2012-11-01

Muscular dystrophies are a group of genetic disorders that specifically affect skeletal muscle and are characterized by progressive muscle degeneration and weakening. To develop therapies and treatments for these diseases, a better understanding of the molecular basis of muscular dystrophies is required. Thus, identification of causative genes mutated in specific disorders and the study of relevant animal models are imperative. Zebrafish genetic models of human muscle disorders often closely resemble disease pathogenesis, and the optical clarity of zebrafish embryos and larvae enables visualization of dynamic molecular processes in vivo. As an adjunct tool, morpholino studies provide insight into the molecular function of genes and allow rapid assessment of candidate genes for human muscular dystrophies. This unique set of attributes makes the zebrafish model system particularly valuable for the study of muscle diseases. This review discusses how recent research using zebrafish has shed light on the pathological basis of muscular dystrophies, with particular focus on the muscle cell membrane and the linkage between the myofibre cytoskeleton and the extracellular matrix.

Using visual lateralization to model learning and memory in zebrafish larvae.

Science.gov (United States)

Andersson, Madelene Åberg; Ek, Fredrik; Olsson, Roger

2015-03-02

Impaired learning and memory are common symptoms of neurodegenerative and neuropsychiatric diseases. Present, there are several behavioural test employed to assess cognitive functions in animal models, including the frequently used novel object recognition (NOR) test. However, although atypical functional brain lateralization has been associated with neuropsychiatric conditions, spanning from schizophrenia to autism, few animal models are available to study this phenomenon in learning and memory deficits. Here we present a visual lateralization NOR model (VLNOR) in zebrafish larvae as an assay that combines brain lateralization and NOR. In zebrafish larvae, learning and memory are generally assessed by habituation, sensitization, or conditioning paradigms, which are all representatives of nondeclarative memory. The VLNOR is the first model for zebrafish larvae that studies a memory similar to the declarative memory described for mammals. We demonstrate that VLNOR can be used to study memory formation, storage, and recall of novel objects, both short and long term, in 10-day-old zebrafish. Furthermore we show that the VLNOR model can be used to study chemical modulation of memory formation and maintenance using dizocilpine (MK-801), a frequently used non-competitive antagonist of the NMDA receptor, used to test putative antipsychotics in animal models.

A reliable, fast and low cost maximum power point tracker for photovoltaic applications

Energy Technology Data Exchange (ETDEWEB)

Enrique, J.M.; Andujar, J.M.; Bohorquez, M.A. [Departamento de Ingenieria Electronica, de Sistemas Informaticos y Automatica, Universidad de Huelva (Spain)

2010-01-15

This work presents a new maximum power point tracker system for photovoltaic applications. The developed system is an analog version of the ''P and O-oriented'' algorithm. It maintains its main advantages: simplicity, reliability and easy practical implementation, and avoids its main disadvantages: inaccurateness and relatively slow response. Additionally, the developed system can be implemented in a practical way at a low cost, which means an added value. The system also shows an excellent behavior for very fast variables in incident radiation levels. (author)

Rapid and Low-cost Prototyping of Medical Devices Using 3D Printed Molds for Liquid Injection Molding

Science.gov (United States)

Chung, Philip; Heller, J. Alex; Etemadi, Mozziyar; Ottoson, Paige E.; Liu, Jonathan A.; Rand, Larry; Roy, Shuvo

2014-01-01

Biologically inert elastomers such as silicone are favorable materials for medical device fabrication, but forming and curing these elastomers using traditional liquid injection molding processes can be an expensive process due to tooling and equipment costs. As a result, it has traditionally been impractical to use liquid injection molding for low-cost, rapid prototyping applications. We have devised a method for rapid and low-cost production of liquid elastomer injection molded devices that utilizes fused deposition modeling 3D printers for mold design and a modified desiccator as an injection system. Low costs and rapid turnaround time in this technique lower the barrier to iteratively designing and prototyping complex elastomer devices. Furthermore, CAD models developed in this process can be later adapted for metal mold tooling design, enabling an easy transition to a traditional injection molding process. We have used this technique to manufacture intravaginal probes involving complex geometries, as well as overmolding over metal parts, using tools commonly available within an academic research laboratory. However, this technique can be easily adapted to create liquid injection molded devices for many other applications. PMID:24998993

Temporally-controlled site-specific recombination in zebrafish.

Directory of Open Access Journals (Sweden)

Stefan Hans

Full Text Available Conventional use of the site-specific recombinase Cre is a powerful technology in mouse, but almost absent in other vertebrate model organisms. In zebrafish, Cre-mediated recombination efficiency was previously very low. Here we show that using transposon-mediated transgenesis, Cre is in fact highly efficient in this organism. Furthermore, temporal control of recombination can be achieved by using the ligand-inducible CreER(T2. Site-specific recombination only occurs upon administration of the drug tamoxifen (TAM or its active metabolite, 4-hydroxy-tamoxifen (4-OHT. Cre-mediated recombination is detectable already 4 or 2 hours after administration of TAM or 4-OHT, demonstrating fast recombination kinetics. In addition, low doses of TAM allow mosaic labeling of single cells. Combined, our results show that conditional Cre/lox will be a valuable tool for both, embryonic and adult zebrafish studies. Furthermore, single copy insertion transgenesis of Cre/lox constructs suggest a strategy suitable also for other organisms.

Zebrafish on a chip: a novel platform for real-time monitoring of drug-induced developmental toxicity.

Directory of Open Access Journals (Sweden)

Yinbao Li

Full Text Available Pharmaceutical safety testing requires a cheap, fast and highly efficient platform for real-time evaluation of drug toxicity and secondary effects. In this study, we have developed a microfluidic system for phenotype-based evaluation of toxic and teratogenic effects of drugs using zebrafish (Danio rerio embryos and larvae as the model organism. The microfluidic chip is composed of two independent functional units, enabling the assessment of zebrafish embryos and larvae. Each unit consists of a fluidic concentration gradient generator and a row of seven culture chambers to accommodate zebrafish. To test the accuracy of this new chip platform, we examined the toxicity and teratogenicity of an anti-asthmatic agent-aminophylline (Apl on 210 embryos and 210 larvae (10 individuals per chamber. The effect of Apl on zebrafish embryonic development was quantitatively assessed by recording a series of physiological indicators such as heart rate, survival rate, body length and hatch rate. Most importantly, a new index called clonic convulsion rate, combined with mortality was used to evaluate the toxicities of Apl on zebrafish larvae. We found that Apl can induce deformity and cardiovascular toxicity in both zebrafish embryos and larvae. This microdevice is a multiplexed testing apparatus that allows for the examination of indexes beyond toxicity and teratogenicity at the sub-organ and cellular levels and provides a potentially cost-effective and rapid pharmaceutical safety assessment tool.

Transforming Ordinary Buildings into Smart Buildings via Low-Cost, Self-Powering Wireless Sensors & Sensor Networks

Energy Technology Data Exchange (ETDEWEB)

Feng, Philip [Case Western Reserve Univ., Cleveland, OH (United States)

2017-06-09

The research objective of this project is to design and demonstrate a low-cost, compact, easy-to-deploy, maintenance-free sensor node technology, and a network of such sensors, which enable the monitoring of multiphysical parameters and can transform today’s ordinary buildings into smart buildings with environmental awareness. We develop the sensor node and network via engineering and integration of existing technologies, including high-efficiency mechanical energy harvesting, and ultralow-power integrated circuits (ICs) for sensing and wireless communication. Through integration and innovative power management via specifically designed low-power control circuits for wireless sensing applications, and tailoring energy-harvesting components to indoor applications, the target products will have smaller volume, higher efficiency, and much lower cost (in both manufacturing and maintenance) than the baseline technology. Our development and commercialization objective is to create prototypes for our target products under the CWRU-Intwine collaboration.

The importance of Zebrafish in biomedical research.

Science.gov (United States)

Tavares, Bárbara; Santos Lopes, Susana

2013-01-01

Zebrafish (Danio rerio) is an ideal model organism for the study of vertebrate development. This is due to the large clutches that each couple produces, with up to 200 embryos every 7 days, and to the fact that the embryos and larvae are small, transparent and undergo rapid external development. Using scientific literature research tools available online and the keywords Zebrafish, biomedical research, human disease, and drug screening, we reviewed original studies and reviews indexed in PubMed. In this review we summarized work conducted with this model for the advancement of our knowledge related to several human diseases. We also focused on the biomedical research being performed in Portugal with the zebrafish model. Powerful live imaging and genetic tools are currently available for zebrafish making it a valuable model in biomedical research. The combination of these properties with the optimization of automated systems for drug screening has transformed the zebrafish into "a top model" in biomedical research, drug discovery and toxicity testing. Furthermore, with the optimization of xenografts technology it will be possible to use zebrafish to aide in the choice of the best therapy for each patient. Zebrafish is an excellent model organism in biomedical research, drug development and in clinical therapy.

Somatic mutagenesis with a Sleeping Beauty transposon system leads to solid tumor formation in zebrafish.

Directory of Open Access Journals (Sweden)

Maura McGrail

2011-04-01

Full Text Available Large-scale sequencing of human cancer genomes and mouse transposon-induced tumors has identified a vast number of genes mutated in different cancers. One of the outstanding challenges in this field is to determine which genes, when mutated, contribute to cellular transformation and tumor progression. To identify new and conserved genes that drive tumorigenesis we have developed a novel cancer model in a distantly related vertebrate species, the zebrafish, Danio rerio. The Sleeping Beauty (SB T2/Onc transposon system was adapted for somatic mutagenesis in zebrafish. The carp ß-actin promoter was cloned into T2/Onc to create T2/OncZ. Two transgenic zebrafish lines that contain large concatemers of T2/OncZ were isolated by injection of linear DNA into the zebrafish embryo. The T2/OncZ transposons were mobilized throughout the zebrafish genome from the transgene array by injecting SB11 transposase RNA at the 1-cell stage. Alternatively, the T2/OncZ zebrafish were crossed to a transgenic line that constitutively expresses SB11 transposase. T2/OncZ transposon integration sites were cloned by ligation-mediated PCR and sequenced on a Genome Analyzer II. Between 700-6800 unique integration events in individual fish were mapped to the zebrafish genome. The data show that introduction of transposase by transgene expression or RNA injection results in an even distribution of transposon re-integration events across the zebrafish genome. SB11 mRNA injection resulted in neoplasms in 10% of adult fish at ∼10 months of age. T2/OncZ-induced zebrafish tumors contain many mutated genes in common with human and mouse cancer genes. These analyses validate our mutagenesis approach and provide additional support for the involvement of these genes in human cancers. The zebrafish T2/OncZ cancer model will be useful for identifying novel and conserved genetic drivers of human cancers.

Developing An Effective Strategy to Configure Assembly Systems Using Lean Concepts

Directory of Open Access Journals (Sweden)

M.Eswaramoorthi

2010-12-01

Full Text Available The manufacturing industry has been pushed to adopt more effective production strategies to meet the challenges of shorter life cycle, higher quality, lower cost and wider variety of customer demands. This increased emphasis on achieving highly adaptive manufacturing with reduction in manufacturing costs and better utilization of manufacturing resources force to implementing new and efficient management techniques in their manufacturing operations. Some of the established tools in this context are lean practices. In manufacturing, assembly is one of the major activities that combine the machined components into final product. Decision on appropriate facility layout and viable assembly sequence (line balancing adaptable to takt time requirement with cost benefit is a challenging task. This paper proposes an integrated cost model for a typical assembly process to determine cost per part more precisely by considering seven types of "contributing factors". This procedure is performed under different takt time conditions to configure the assembly system in terms of cost per piece and to decide the adaptable layout. A prototype assembly system is established in this research to demonstrate the effectiveness of the cost model. The results show that there are significant variations in cost per piece with respect to changes in layout configurations and takt time.

Low-cost high purity production

Science.gov (United States)

Kapur, V. K.

1978-01-01

Economical process produces high-purity silicon crystals suitable for use in solar cells. Reaction is strongly exothermic and can be initiated at relatively low temperature, making it potentially suitable for development into low-cost commercial process. Important advantages include exothermic character and comparatively low process temperatures. These could lead to significant savings in equipment and energy costs.

Zebrafish neurobehavioral phenomics for aquatic neuropharmacology and toxicology research.

Science.gov (United States)

Kalueff, Allan V; Echevarria, David J; Homechaudhuri, Sumit; Stewart, Adam Michael; Collier, Adam D; Kaluyeva, Aleksandra A; Li, Shaomin; Liu, Yingcong; Chen, Peirong; Wang, JiaJia; Yang, Lei; Mitra, Anisa; Pal, Subharthi; Chaudhuri, Adwitiya; Roy, Anwesha; Biswas, Missidona; Roy, Dola; Podder, Anupam; Poudel, Manoj K; Katare, Deepshikha P; Mani, Ruchi J; Kyzar, Evan J; Gaikwad, Siddharth; Nguyen, Michael; Song, Cai

2016-01-01

Zebrafish (Danio rerio) are rapidly emerging as an important model organism for aquatic neuropharmacology and toxicology research. The behavioral/phenotypic complexity of zebrafish allows for thorough dissection of complex human brain disorders and drug-evoked pathological states. As numerous zebrafish models become available with a wide spectrum of behavioral, genetic, and environmental methods to test novel drugs, here we discuss recent zebrafish phenomics methods to facilitate drug discovery, particularly in the field of biological psychiatry. Additionally, behavioral, neurological, and endocrine endpoints are becoming increasingly well-characterized in zebrafish, making them an inexpensive, robust and effective model for toxicology research and pharmacological screening. We also discuss zebrafish behavioral phenotypes, experimental considerations, pharmacological candidates and relevance of zebrafish neurophenomics to other 'omics' (e.g., genomic, proteomic) approaches. Finally, we critically evaluate the limitations of utilizing this model organism, and outline future strategies of research in the field of zebrafish phenomics. Copyright © 2015 Elsevier B.V. All rights reserved.

A Low-Cost Audio Prescription Labeling System Using RFID for Thai Visually-Impaired People.

Science.gov (United States)

Lertwiriyaprapa, Titipong; Fakkheow, Pirapong

2015-01-01

This research aims to develop a low-cost audio prescription labeling (APL) system for visually-impaired people by using the RFID system. The developed APL system includes the APL machine and APL software. The APL machine is for visually-impaired people while APL software allows caregivers to record all important information into the APL machine. The main objective of the development of the APL machine is to reduce costs and size by designing all of the electronic devices to fit into one print circuit board. Also, it is designed so that it is easy to use and can become an electronic aid for daily living. The developed APL software is based on Java and MySQL, both of which can operate on various operating platforms and are easy to develop as commercial software. The developed APL system was first evaluated by 5 experts. The APL system was also evaluated by 50 actual visually-impaired people (30 elders and 20 blind individuals) and 20 caregivers, pharmacists and nurses. After using the APL system, evaluations were carried out, and it can be concluded from the evaluation results that this proposed APL system can be effectively used for helping visually-impaired people in terms of self-medication.

A Security Mechanism for library management system using low cost RFID tags

Directory of Open Access Journals (Sweden)

V. Nagalakshmi

2007-02-01

Full Text Available Radio Frequency Identification (RFID systems will become pervasive in our daily lives due to their low cost and easy to use characteristics[1]. This paper presents a methodology of using low cost RFID tags for a library management system to protect the books from unauthorized capturing and usage. Every object to be identified in the RFID system is physically labeled with a tag. In the proposed method a book or a magazine or a CD is identified with the RFID tag. Whenever a book is issued to any user of the library, the RFID reader will capture the information of that book and compares it with the related information of the book in the Online Public Access Catalogue (OPAC and issues the book to the user depending on his identity in the database. If any unauthorized person intends to take the book the RFID reader will immediately respond to that and make sure that it was not issued. If any body tries to remove the tag it can be traced with the help of location device. Keywords: RFID, OPAC, Unauthorized user, tag, Reader.

A Low Cost Rokkaku Kite Setup for Aerial Photogrammetric System

Science.gov (United States)

Khan, A. F.; Khurshid, K.; Saleh, N.; Yousuf, A. A.

2015-03-01

Orthogonally Projected Area (OPA) of a geographical feature has primarily been studied utilizing rather time consuming field based sampling techniques. Remote sensing on the contrary provides the ability to acquire large scale data at a snapshot of time and lets the OPA to be calculated conveniently and with reasonable accuracy. Unfortunately satellite based remote sensing provides data at high cost and limited spatial resolution for scientific studies focused at small areas such as micro lakes micro ecosystems, etc. More importantly, recent satellite data may not be readily available for a particular location. This paper describes a low cost photogrammetric system to measure the OPA of a small scale geographic feature such as a plot of land, micro lake or an archaeological site, etc. Fitted with a consumer grade digital imaging system, a Rokkaku kite aerial platform with stable flight characteristics is designed and fabricated for image acquisition. The data processing procedure involves automatic Ground Control Point (GCP) detection, intelligent target area shape determination with minimal human input. A Graphical User Interface (GUI) is built from scratch in MATLAB to allow the user to conveniently process the acquired data, archive and retrieve the results. Extensive on-field experimentation consists of multiple geographic features including flat land surfaces, buildings, undulating rural areas, and an irregular shaped micro lake, etc. Our results show that the proposed system is not only low cost, but provides a framework that is easy and fast to setup while maintaining the required constraints on the accuracy.

Mars Relay Satellite: Key to Enabling Low-Cost Exploration Missions

Science.gov (United States)

Hastrup, R.; Cesarone, R.; Miller, A.

1993-01-01

Recently, there has been increasing evidence of a renewed focus on Mars exploration both by NASA and the international community. The thrust of this renewed interest appears to be manifesting itself in numerous low-cost missions employing small, light weight elements, which utilize advanced technologies including integrated microelectronics. A formidable problem facing these low-cost missions is communications with Earth. Providing adequate direct-link performance has very significant impacts on spacecraft power, pointing, mass and overall complexity. Additionally, for elements at or near the surface of Mars, there are serious connectivity constraints, especially at higher latitudes, which lose view of Earth for up to many months at a time. This paper will discuss the role a Mars relay satellite can play in enabling and enhancing low-cost missions to Mars...

Easy-to-use interface

International Nuclear Information System (INIS)

Blattner, D O; Blattner, M M; Tong, Y.

1999-01-01

Easy-to-use interfaces are a class of interfaces that fall between public access interfaces and graphical user interfaces in usability and cognitive difficulty. We describe characteristics of easy-to-use interfaces by the properties of four dimensions: selection, navigation, direct manipulation, and contextual metaphors. Another constraint we introduced was to include as little text as possible, and what text we have will be in at least four languages. Formative evaluations were conducted to identify and isolate these characteristics. Our application is a visual interface for a home automation system intended for a diverse set of users. The design will be expanded to accommodate the visually disabled in the near future

Pi-Sat: A Low Cost Small Satellite and Distributed Spacecraft Mission System Test Platform

Science.gov (United States)

Cudmore, Alan

2015-01-01

Current technology and budget trends indicate a shift in satellite architectures from large, expensive single satellite missions, to small, low cost distributed spacecraft missions. At the center of this shift is the SmallSatCubesat architecture. The primary goal of the Pi-Sat project is to create a low cost, and easy to use Distributed Spacecraft Mission (DSM) test bed to facilitate the research and development of next-generation DSM technologies and concepts. This test bed also serves as a realistic software development platform for Small Satellite and Cubesat architectures. The Pi-Sat is based on the popular $35 Raspberry Pi single board computer featuring a 700Mhz ARM processor, 512MB of RAM, a flash memory card, and a wealth of IO options. The Raspberry Pi runs the Linux operating system and can easily run Code 582s Core Flight System flight software architecture. The low cost and high availability of the Raspberry Pi make it an ideal platform for a Distributed Spacecraft Mission and Cubesat software development. The Pi-Sat models currently include a Pi-Sat 1U Cube, a Pi-Sat Wireless Node, and a Pi-Sat Cubesat processor card.The Pi-Sat project takes advantage of many popular trends in the Maker community including low cost electronics, 3d printing, and rapid prototyping in order to provide a realistic platform for flight software testing, training, and technology development. The Pi-Sat has also provided fantastic hands on training opportunities for NASA summer interns and Pathways students.

Moving toward rapid and low-cost point-of-care molecular diagnostics with a repurposed 3D printer and RPA.

Science.gov (United States)

Chan, Kamfai; Wong, Pui-Yan; Parikh, Chaitanya; Wong, Season

2018-03-15

Traditionally, the majority of nucleic acid amplification-based molecular diagnostic tests are done in centralized settings. In recent years, point-of-care tests have been developed for use in low-resource settings away from central laboratories. While most experts agree that point-of-care molecular tests are greatly needed, their availability as cost-effective and easy-to-operate tests remains an unmet goal. In this article, we discuss our efforts to develop a recombinase polymerase amplification reaction-based test that will meet these criteria. First, we describe our efforts in repurposing a low-cost 3D printer as a platform that can carry out medium-throughput, rapid, and high-performing nucleic acid extraction. Next, we address how these purified templates can be rapidly amplified and analyzed using the 3D printer's heated bed or the deconstructed, low-cost thermal cycler we have developed. In both approaches, real-time isothermal amplification and detection of template DNA or RNA can be accomplished using a low-cost portable detector or smartphone camera. Last, we demonstrate the capability of our technologies using foodborne pathogens and the Zika virus. Our low-cost approach does not employ complicated and high-cost components, making it suitable for resource-limited settings. When integrated and commercialized, it will offer simple sample-to-answer molecular diagnostics. Copyright © 2018 Elsevier Inc. All rights reserved.

Nanodiamond for biolabelling and toxicity evaluation in the zebrafish embryo in vivo.

Science.gov (United States)

Lin, Y-C; Wu, K-T; Lin, Z-R; Perevedentseva, E; Karmenyan, A; Lin, M-D; Cheng, C-L

2016-08-01

Nanodiamond (ND) has been proposed for various biomedical applications, including bioimaging, biosensing and drug delivery, owing to its physical-chemical properties and biocompatibility. Particularly, ND has been demonstrated as fluorescence- and Raman-detectable labels in many cellular models. Different surface functionalization methods have been developed, varying the ND's surface properties and rendering the possibility to attach biomolecules to provide interaction with biological targets. For this, toxicity is of major concern in animal models. Aside from cellular models, a cost-effective animal test will greatly facilitate the development of applications. In this study, we use the rapid, sensitive and reproducible zebrafish embryo model for in vivo nanotoxicity test. We optimize the conditions for using this animal model and analyze the zebrafish embryonic development in the presence of ND. ND is observed in the embryo in vivo using laser confocal fluorescence microscopy and fluorescence lifetime imaging. Using the zebrafish model for a safety evaluation of ND-based nanolabel is discussed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chronic perfluorooctane sulfonate (PFOS) exposure induces hepatic steatosis in zebrafish

International Nuclear Information System (INIS)

Cheng, Jiangfei; Lv, Suping; Nie, Shangfei; Liu, Jing; Tong, Shoufang; Kang, Ning; Xiao, Yanyan; Dong, Qiaoxiang; Huang, Changjiang; Yang, Dongren

2016-01-01

Highlights: • PFOS chronic exposure induces sex-dependent hepatic steotosis in zebrafish. • PFOS interferes with β-oxidation, lipid synthesis, and lipid hepatic export process. • Zebrafish could be used as an alternative model for PFOS chronic toxicity screening. - Abstract: Perfluorooctane sulfonate (PFOS), one persistent organic pollutant, has been widely detected in the environment, wildlife and human. Currently few studies have documented the effects of chronic PFOS exposure on lipid metabolism, especially in aquatic organisms. The underlying mechanisms of hepatotoxicity induced by chronic PFOS exposure are still largely unknown. The present study defined the effects of chronic exposure to low level of PFOS on lipid metabolism using zebrafish as a model system. Our findings revealed a severe hepatic steatosis in the liver of males treated with 0.5 μM PFOS as evidenced by hepatosomatic index, histological assessment and liver lipid profiles. Quantitative PCR assay further indicated that PFOS significantly increase the transcriptional expression of nuclear receptors (nr1h3, rara, rxrgb, nr1l2) and the genes associated with fatty acid oxidation (acox1, acadm, cpt1a). In addition, chronic PFOS exposure significantly decreased liver ATP content and serum level of VLDL/LDL lipoprotein in males. Taken together, these findings suggest that chronic PFOS exposure induces hepatic steatosis in zebrafish via disturbing lipid biosynthesis, fatty acid β-oxidation and excretion of VLDL/LDL lipoprotein, and also demonstrate the validity of using zebrafish as an alternative model for PFOS chronic toxicity screening.

Chronic perfluorooctane sulfonate (PFOS) exposure induces hepatic steatosis in zebrafish

Energy Technology Data Exchange (ETDEWEB)

Cheng, Jiangfei; Lv, Suping; Nie, Shangfei; Liu, Jing; Tong, Shoufang; Kang, Ning; Xiao, Yanyan; Dong, Qiaoxiang [Zhejiang Provincial Key Laboratory for Technology and Application of Model Organisms (China); Institute of Environmental Safety and Human Health, Wenzhou Medical University, Wenzhou, 325035 (China); Huang, Changjiang, E-mail: cjhuang5711@163.com [Zhejiang Provincial Key Laboratory for Technology and Application of Model Organisms (China); Institute of Environmental Safety and Human Health, Wenzhou Medical University, Wenzhou, 325035 (China); Yang, Dongren, E-mail: yangdongren@yahoo.com [Zhejiang Provincial Key Laboratory for Technology and Application of Model Organisms (China); Institute of Environmental Safety and Human Health, Wenzhou Medical University, Wenzhou, 325035 (China)

2016-07-15

Highlights: • PFOS chronic exposure induces sex-dependent hepatic steotosis in zebrafish. • PFOS interferes with β-oxidation, lipid synthesis, and lipid hepatic export process. • Zebrafish could be used as an alternative model for PFOS chronic toxicity screening. - Abstract: Perfluorooctane sulfonate (PFOS), one persistent organic pollutant, has been widely detected in the environment, wildlife and human. Currently few studies have documented the effects of chronic PFOS exposure on lipid metabolism, especially in aquatic organisms. The underlying mechanisms of hepatotoxicity induced by chronic PFOS exposure are still largely unknown. The present study defined the effects of chronic exposure to low level of PFOS on lipid metabolism using zebrafish as a model system. Our findings revealed a severe hepatic steatosis in the liver of males treated with 0.5 μM PFOS as evidenced by hepatosomatic index, histological assessment and liver lipid profiles. Quantitative PCR assay further indicated that PFOS significantly increase the transcriptional expression of nuclear receptors (nr1h3, rara, rxrgb, nr1l2) and the genes associated with fatty acid oxidation (acox1, acadm, cpt1a). In addition, chronic PFOS exposure significantly decreased liver ATP content and serum level of VLDL/LDL lipoprotein in males. Taken together, these findings suggest that chronic PFOS exposure induces hepatic steatosis in zebrafish via disturbing lipid biosynthesis, fatty acid β-oxidation and excretion of VLDL/LDL lipoprotein, and also demonstrate the validity of using zebrafish as an alternative model for PFOS chronic toxicity screening.

Developmental lead exposure causes startle response deficits in zebrafish.

Science.gov (United States)

Rice, Clinton; Ghorai, Jugal K; Zalewski, Kathryn; Weber, Daniel N

2011-10-01

Lead (Pb(2+)) exposure continues to be an important concern for fish populations. Research is required to assess the long-term behavioral effects of low-level concentrations of Pb(2+) and the physiological mechanisms that control those behaviors. Newly fertilized zebrafish embryos (max) and escape time. With increasing exposure concentrations, a larger number of larvae failed to respond to even the initial tap and, for those that did respond, ceased responding earlier than control larvae. These differences were more pronounced at a frequency of 4 taps/s. (2) Response to a visual stimulus: Fish, exposed as embryos (2-24 hpf) to Pb(2+) (0-10 μM) were tested as adults under low light conditions (≈ 60 μW/m(2)) for visual responses to a rotating black bar. Visual responses were significantly degraded at Pb(2+) concentrations of 30 nM. These data suggest that zebrafish are viable models for short- and long-term sensorimotor deficits induced by acute, low-level developmental Pb(2+) exposures. Copyright © 2011 Elsevier B.V. All rights reserved.

Episodic-like memory in zebrafish.

Science.gov (United States)

Hamilton, Trevor J; Myggland, Allison; Duperreault, Erika; May, Zacnicte; Gallup, Joshua; Powell, Russell A; Schalomon, Melike; Digweed, Shannon M

2016-11-01

Episodic-like memory tests often aid in determining an animal's ability to recall the what, where, and which (context) of an event. To date, this type of memory has been demonstrated in humans, wild chacma baboons, corvids (Scrub jays), humming birds, mice, rats, Yucatan minipigs, and cuttlefish. The potential for this type of memory in zebrafish remains unexplored even though they are quickly becoming an essential model organism for the study of a variety of human cognitive and mental disorders. Here we explore the episodic-like capabilities of zebrafish (Danio rerio) in a previously established mammalian memory paradigm. We demonstrate that when zebrafish were presented with a familiar object in a familiar context but a novel location within that context, they spend more time in the novel quadrant. Thus, zebrafish display episodic-like memory as they remember what object they saw, where they saw it (quadrant location), and on which occasion (yellow or blue walls) it was presented.

Enzymatic activity and gene expression changes in zebrafish embryos and larvae exposed to pesticides diazinon and diuron.

Science.gov (United States)

Velki, Mirna; Meyer-Alert, Henriette; Seiler, Thomas-Benjamin; Hollert, Henner

2017-12-01

The zebrafish as a test organism enables the investigation of effects on a wide range of biological levels from molecular level to the whole-organism level. The use of fish embryos represents an attractive model for studies aimed at understanding toxic mechanisms and the environmental risk assessment of chemicals. In the present study, a zebrafish (Danio rerio) in vivo model was employed in order to assess the effects of two commonly used pesticides, the insecticide diazinon and the herbicide diuron, on zebrafish early life stages. Since it was previously established that diazinon and diuron cause effects at the whole-organism level, this study assessed the suborganismic responses to exposure to these pesticides and the enzymatic responses (biochemical level) and the gene expression changes (molecular level) were analyzed. Different exposure scenarios were employed and the following endpoints measured: acetylcholinesterase (AChE), carboxylesterase (CES), ethoxyresorufin-O-deethylase (EROD), glutathione-S-transferase (GST), catalase (CAT) and glutathione peroxidase (GPx) activities; and gene expressions of the corresponding genes: acetylcholinesterase (ache), carboxylesterase (ces2), cytochrome P450 (cyp1a), glutathione-S-transferase (gstp1), catalase (cat), glutathione peroxidase (gpx1a) and additionally glutathione reductase (gsr). Significant changes at both the biochemical and the molecular level were detected. In addition, different sensitivities of different developmental stages of zebrafish were determined and partial recovery of the enzyme activity 48h after the end of the exposure was observed. The observed disparity between gene expression changes and alterations in enzyme activities points to the necessity of monitoring changes at different levels of biological organization. Different exposure scenarios, together with a comparison of the responses at the biochemical and molecular level, provide valuable data on the effects of diazinon and diuron on low

Hidden costs of low-cost screening mammography

International Nuclear Information System (INIS)

Cyrlak, D.

1987-01-01

Twenty-two hundred women in Orange County, California, took part in a low-cost mammography screening project sponsored by the American Cancer Society and the KCBS-TV. Patients were followed up by telephone and questioned about actual costs incurred as a result of screening mammography, including costs of repeated and follow-up mammograms, US examinations and surgical consultations. The total number of biopsies, cancers found, and the costs involved were investigated. The authors' results suggest that particularly in centers with a high positive call rate, the cost of screening mammograms accounts for only a small proportion of the medical costs

Preliminary study of Low-Cost Micro Gas Turbine

Science.gov (United States)

Fikri, M.; Ridzuan, M.; Salleh, Hamidon

2016-11-01

The electricity consumption nowadays has increased due to the increasing development of portable electronic devices. The development of low cost micro gas turbine engine, which is designed for the purposes of new electrical generation Micro turbines are a relatively new distributed generation technology being used for stationary energy generation applications. They are a type of combustion turbine that produces both heat and electricity on a relatively small scaled.. This research are focusing of developing a low-cost micro gas turbine engine based on automotive turbocharger and to evaluation the performance of the developed micro gas turbine. The test rig engine basically was constructed using a Nissan 45V3 automotive turbocharger, containing compressor and turbine assemblies on a common shaft. The operating performance of developed micro gas turbine was analyzed experimentally with the increment of 5000 RPM on the compressor speed. The speed of the compressor was limited at 70000 RPM and only 1000 degree Celsius at maximum were allowed to operate the system in order to avoid any failure on the turbocharger bearing and the other components. Performance parameters such as inlet temperature, compressor temperature, exhaust gas temperature, and fuel and air flow rates were measured. The data was collected electronically by 74972A data acquisition and evaluated manually by calculation. From the independent test shows the result of the system, The speed of the LP turbine can be reached up to 35000 RPM and produced 18.5kw of mechanical power.

Toxicity of multi-walled carbon nanotubes, graphene oxide, and reduced graphene oxide to zebrafish embryos.

Science.gov (United States)

Liu, Xiao Tong; Mu, Xi Yan; Wu, Xiao Li; Meng, Li Xuan; Guan, Wen Bi; Ma, Yong Qiang; Sun, Hua; Wang, Cheng Ju; Li, Xue Feng

2014-09-01

This study was aimed to investigate the toxic effects of 3 nanomaterials, i.e. multi-walled carbon nanotubes (MWCNTs), graphene oxide (GO), and reduced graphene oxide (RGO), on zebrafish embryos. The 2-h post-fertilization (hpf) zebrafish embryos were exposed to MWCNTs, GO, and RGO at different concentrations (1, 5, 10, 50, 100 mg/L) for 96 h. Afterwards, the effects of the 3 nanomateria on spontaneous movement, heart rate, hatching rate, length of larvae, mortality, and malformations ls were evaluated. Statistical analysis indicated that RGO significantly inhibited the hatching of zebrafish embryos. Furthermore, RGO and MWCNTs decreased the length of the hatched larvae at 96 hpf. No obvious morphological malformation or mortality was observed in the zebrafish embryos after exposure to the three nanomaterials. MWCNTs, GO, and RGO were all toxic to zebrafish embryos to influence embryos hatching and larvae length. Although no obvious morphological malformation and mortality were observed in exposed zebrafish embryos, further studies on the toxicity of the three nanomaterials are still needed. Copyright © 2014 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

The Zebrafish Model Organism Database (ZFIN)

Data.gov (United States)

U.S. Department of Health & Human Services — ZFIN serves as the zebrafish model organism database. It aims to: a) be the community database resource for the laboratory use of zebrafish, b) develop and support...

Flexible Assembly Solar Technology (FAST) Final Technical Report

Energy Technology Data Exchange (ETDEWEB)

Toister, Elad [BrightSource Energy Inc., Jerusalem (Israel)

2014-11-06

The Flexible Assembly Solar Technology (FAST) project was initiated by BrightSource in an attempt to provide potential solar field EPC contractors with an effective set of tools to perform specific construction tasks. These tasks are mostly associated with heliostat assembly and installation, and require customized non-standard tools. The FAST concept focuses on low equipment cost, reduced setup time and increased assembly throughput as compared to the Ivanpah solar field construction tools.

Zebrafish swimming in the flow: a particle image velocimetry study

Directory of Open Access Journals (Sweden)

Violet Mwaffo

2017-11-01

Full Text Available Zebrafish is emerging as a species of choice for the study of a number of biomechanics problems, including balance development, schooling, and neuromuscular transmission. The precise quantification of the flow physics around swimming zebrafish is critical toward a mechanistic understanding of the complex swimming style of this fresh-water species. Although previous studies have elucidated the vortical structures in the wake of zebrafish swimming in placid water, the flow physics of zebrafish swimming against a water current remains unexplored. In an effort to illuminate zebrafish swimming in a dynamic environment reminiscent of its natural habitat, we experimentally investigated the locomotion and hydrodynamics of a single zebrafish swimming in a miniature water tunnel using particle image velocimetry. Our results on zebrafish locomotion detail the role of flow speed on tail beat undulations, heading direction, and swimming speed. Our findings on zebrafish hydrodynamics offer a precise quantification of vortex shedding during zebrafish swimming and demonstrate that locomotory patterns play a central role on the flow physics. This knowledge may help clarify the evolutionary advantage of burst and cruise swimming movements in zebrafish.

Metrology for ITER Assembly

International Nuclear Information System (INIS)

Bogusch, E.

2006-01-01

The overall dimensions of the ITER Tokamak and the particular assembly sequence preclude the use of conventional optical metrology, mechanical jigs and traditional dimensional control equipment, as used for the assembly of smaller, previous generation, fusion devices. This paper describes the state of the art of the capabilities of available metrology systems, with reference to the previous experience in Fusion engineering and in other industries. Two complementary procedures of transferring datum from the primary datum network on the bioshield to the secondary datum s inside the VV with the desired accuracy of about 0.1 mm is described, one method using the access directly through the ports and the other using transfer techniques, developed during the co-operation with ITER/EFDA. Another important task described is the development of a method for the rapid and easy measurement of the gaps between sectors, required for the production of the customised splice plates between them. The scope of the paper includes the evaluation of the composition and cost of the systems and team of technical staff required to meet the requirements of the assembly procedure. The results from a practical, full-scale demonstration of the methodologies used, using the proposed equipment, is described. This work has demonstrated the feasibility of achieving the necessary accuracies for the successful building of ITER. (author)

A characterization of the ZFL cell line and primary hepatocytes as in vitro liver cell models for the zebrafish (Danio rerio)

International Nuclear Information System (INIS)

Eide, Marta; Rusten, Marte; Male, Rune; Jensen, Knut Helge Midtbø; Goksøyr, Anders

2014-01-01

Highlights: •The ZFL cell line and primary hepatocytes were characterized. •Basic and induced expression of nuclear receptors and target genes were found. •The ZFL cell line expresses very low basic levels of most genes. •The ZFL cells have low induction of gene expression following exposures. •Primary hepatocytes show large sex-dependent differences in gene expression. -- Abstract: The zebrafish (Danio rerio) is a widely used model species in biomedical research. The ZFL cell line, established from zebrafish liver, and freshly isolated primary hepatocytes from zebrafish have been used in several toxicological studies. However, no previous report has compared and characterized these two systems at the level of gene expression. The aim of this study was to evaluate the ZFL cell line in comparison to primary hepatocytes as in vitro models for studying effects of environmental contaminants in zebrafish liver. Using quantitative real-time PCR, the basal level and transcriptional induction potential of key genes involved in toxic responses in the ZFL cell line, primary hepatocytes and whole liver from zebrafish were compared. The study showed that the ZFL cells have lower levels of mRNA of most selected genes compared to zebrafish liver. The induced gene transcription following exposure to ligand was much lower in ZFL cells compared to zebrafish primary hepatocytes at the doses tested. Importantly, oestrogen receptor and vitellogenin genes showed low basal transcription and no induction response in the ZFL cell line. In conclusion, it appears that primary hepatocytes are well suited for studying environmental contaminants including xenoestrogens, but may show large sex-dependent differences in gene transcription. The ZFL cell line shows potential in toxicological studies involving the aryl hydrocarbon receptor pathway. However, low potential for transcriptional induction of genes in general should be expected, especially notable when studying estrogenic

A characterization of the ZFL cell line and primary hepatocytes as in vitro liver cell models for the zebrafish (Danio rerio)

Energy Technology Data Exchange (ETDEWEB)

Eide, Marta, E-mail: marta.eide@bio.uib.no [Department of Biology, University of Bergen, Bergen (Norway); Rusten, Marte; Male, Rune [Department of Molecular Biology, University of Bergen, Bergen (Norway); Jensen, Knut Helge Midtbø; Goksøyr, Anders [Department of Biology, University of Bergen, Bergen (Norway)

2014-02-15

Highlights: •The ZFL cell line and primary hepatocytes were characterized. •Basic and induced expression of nuclear receptors and target genes were found. •The ZFL cell line expresses very low basic levels of most genes. •The ZFL cells have low induction of gene expression following exposures. •Primary hepatocytes show large sex-dependent differences in gene expression. -- Abstract: The zebrafish (Danio rerio) is a widely used model species in biomedical research. The ZFL cell line, established from zebrafish liver, and freshly isolated primary hepatocytes from zebrafish have been used in several toxicological studies. However, no previous report has compared and characterized these two systems at the level of gene expression. The aim of this study was to evaluate the ZFL cell line in comparison to primary hepatocytes as in vitro models for studying effects of environmental contaminants in zebrafish liver. Using quantitative real-time PCR, the basal level and transcriptional induction potential of key genes involved in toxic responses in the ZFL cell line, primary hepatocytes and whole liver from zebrafish were compared. The study showed that the ZFL cells have lower levels of mRNA of most selected genes compared to zebrafish liver. The induced gene transcription following exposure to ligand was much lower in ZFL cells compared to zebrafish primary hepatocytes at the doses tested. Importantly, oestrogen receptor and vitellogenin genes showed low basal transcription and no induction response in the ZFL cell line. In conclusion, it appears that primary hepatocytes are well suited for studying environmental contaminants including xenoestrogens, but may show large sex-dependent differences in gene transcription. The ZFL cell line shows potential in toxicological studies involving the aryl hydrocarbon receptor pathway. However, low potential for transcriptional induction of genes in general should be expected, especially notable when studying estrogenic

Low-cost carbon-silicon nanocomposite anodes for lithium ion batteries.

Science.gov (United States)

Badi, Nacer; Erra, Abhinay Reddy; Hernandez, Francisco C Robles; Okonkwo, Anderson O; Hobosyan, Mkhitar; Martirosyan, Karen S

2014-01-01

The specific energy of the existing lithium ion battery cells is limited because intercalation electrodes made of activated carbon (AC) materials have limited lithium ion storage capacities. Carbon nanotubes, graphene, and carbon nanofibers are the most sought alternatives to replace AC materials but their synthesis cost makes them highly prohibitive. Silicon has recently emerged as a strong candidate to replace existing graphite anodes due to its inherently large specific capacity and low working potential. However, pure silicon electrodes have shown poor mechanical integrity due to the dramatic expansion of the material during battery operation. This results in high irreversible capacity and short cycle life. We report on the synthesis and use of carbon and hybrid carbon-silicon nanostructures made by a simplified thermo-mechanical milling process to produce low-cost high-energy lithium ion battery anodes. Our work is based on an abundant, cost-effective, and easy-to-launch source of carbon soot having amorphous nature in combination with scrap silicon with crystalline nature. The carbon soot is transformed in situ into graphene and graphitic carbon during mechanical milling leading to superior elastic properties. Micro-Raman mapping shows a well-dispersed microstructure for both carbon and silicon. The fabricated composites are used for battery anodes, and the results are compared with commercial anodes from MTI Corporation. The anodes are integrated in batteries and tested; the results are compared to those seen in commercial batteries. For quick laboratory assessment, all electrochemical cells were fabricated under available environment conditions and they were tested at room temperature. Initial electrochemical analysis results on specific capacity, efficiency, and cyclability in comparison to currently available AC counterpart are promising to advance cost-effective commercial lithium ion battery technology. The electrochemical performance observed for

Swimming Effects on Developing Zebrafish

NARCIS (Netherlands)

Kranenbarg, S.; Pelster, B.

2013-01-01

Zebrafish represent an important vertebrate model species in developmental biology. This chapter reviews the effects of exercise on the development of the musculoskeletal system, the cardiovascular system, metabolic capacities of developing zebrafish, and regulation of these processes on the gene

A low-cost multichannel analyzer with data reduction assembly for continuous air monitoring system

International Nuclear Information System (INIS)

Zoghi, B.; Lee, Y.; Nelson, D.C.

1992-01-01

This paper reports on a microcontroller-based multichannel analyzer (MCA) with a data reduction assembly (DRA) for a plutonium continuous air monitor (CAM) system. The MCA is capable of detecting the airborne alpha emitters in the presence of radon daughter products. The pulse output from the preamplifier has been stretched to allow the peak detector sufficient time to capture the pulse height. The pulse amplitude conversion, the data acquisition, and the output functions are carried out fully by software. The DRA consists of a data reduction unit (DRU) and its operator interface panel. The data reduction assembly has the ability to be networked to a single PC with up to 332 different CAM's remotely connected to it

Macrophage–Microbe Interactions: Lessons from the Zebrafish Model

Directory of Open Access Journals (Sweden)

Nagisa Yoshida

2017-12-01

Full Text Available Macrophages provide front line defense against infections. The study of macrophage–microbe interplay is thus crucial for understanding pathogenesis and infection control. Zebrafish (Danio rerio larvae provide a unique platform to study macrophage–microbe interactions in vivo, from the level of the single cell to the whole organism. Studies using zebrafish allow non-invasive, real-time visualization of macrophage recruitment and phagocytosis. Furthermore, the chemical and genetic tractability of zebrafish has been central to decipher the complex role of macrophages during infection. Here, we discuss the latest developments using zebrafish models of bacterial and fungal infection. We also review novel aspects of macrophage biology revealed by zebrafish, which can potentiate development of new therapeutic strategies for humans.

Morphological alterations and acetylcholinesterase and monoamine oxidase inhibition in liver of zebrafish exposed to Aphanizomenon flos-aquae DC-1 aphantoxins

Energy Technology Data Exchange (ETDEWEB)

Zhang, De Lu, E-mail: deluzh@163.com [Department of Lifescience and Biotechnology, School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070 (China); Zhang, Jing [College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072 (China); Hu, Chun Xiang, E-mail: cxhu@ihb.ac.cn [Key Laboratory of Algal Biology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072 (China); Wang, Gao Hong; Li, Dun Hai; Liu, Yong Ding [Key Laboratory of Algal Biology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072 (China)

2014-12-15

Highlights: • Aphantoxins induced zebrafish hepatic physiological and morphological changes. • AChE and MAO inhibition reflected abnormality of neurotransmitter inactivation. • ROS advance and T-AOC reduction suggested oxidative stress. • ALT, AST, histological and ultrastructural alterations indicated hepatic damage. - Abstract: Aphanizomenon flos-aquae is a cyanobacterium that produces neurotoxins or paralytic shellfish poisons (PSPs) called aphantoxins, which present threats to environmental safety and human health via eutrophication of water bodies worldwide. Although the molecular mechanisms of this neurotoxin have been studied, many questions remain unsolved, including those relating to in vivo hepatic neurotransmitter inactivation, physiological detoxification and histological and ultrastructural alterations. Aphantoxins extracted from the natural strain of A. flos-aquae DC-1 were analyzed by high-performance liquid chromatography. The main components were gonyautoxins 1 and 5 (GTX1, GTX5) and neosaxitoxin (neoSTX), which comprised 34.04%, 21.28%, and 12.77% respectively. Zebrafish (Danio rerio) were exposed intraperitoneally to 5.3 or 7.61 μg STX equivalents (eq)/kg (low and high doses, respectively) of A. flos-aquae DC-1 aphantoxins. Morphological alterations and changes in neurotransmitter conduction functions of acetylcholinesterase (AChE) and monoamine oxidase (MAO) in zebrafish liver were detected at different time points 1–24 h post-exposure. Aphantoxin significantly enhanced hepatic alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities and histological and ultrastructural damage in zebrafish liver at 3–12 h post-exposure. Toxin exposure increased the reactive oxygen species content and reduced total antioxidative capacity in zebrafish liver, suggesting oxidative stress. AChE and MAO activities were significantly inhibited, suggesting neurotransmitter inactivation/conduction function abnormalities in zebrafish

Low cost open data acquisition system for biomedical applications

Science.gov (United States)

Zabolotny, Wojciech M.; Laniewski-Wollk, Przemyslaw; Zaworski, Wojciech

2005-09-01

In the biomedical applications it is often necessary to collect measurement data from different devices. It is relatively easy, if the devices are equipped with a MIB or Ethernet interface, however often they feature only the asynchronous serial link, and sometimes the measured values are available only as the analog signals. The system presented in the paper is a low cost alternative to commercially available data acquisition systems. The hardware and software architecture of the system is fully open, so it is possible to customize it for particular needs. The presented system offers various possibilities to connect it to the computer based data processing unit - e.g. using the USB or Ethernet ports. Both interfaces allow also to use many such systems in parallel to increase amount of serial and analog inputs. The open source software used in the system makes possible to process the acquired data with standard tools like MATLAB, Scilab or Octave, or with a dedicated, user supplied application.

Analysis of reconfigurable assembly system framing systems in automotive industry

Directory of Open Access Journals (Sweden)

Md Zain Mohamad Zamri

2017-01-01

Full Text Available Current trend in automotive industry shows increasing demand for multiple models with lean production. Prior to that, automotive manufacturing systems evolved from mass production to flexible automation. Material handling systems and equipment in a single assembly line with multiple models require high investment but with low throughput thus making production cost relatively high. Current assembly process of side structure and undercarriage with downtime occurrence during assembly process affecting production performance (quality, cost and delivery. Manufacturing facilities should allow more flexibility and increase intelligence evolving toward novel reconfigurable assembly systems (RAS. RAS is envisaged capable of increasing factor flexibility and responsiveness by incorporating assembly jig, robot and framing, which could be next generation of world class automotive assembly systems. This project research proposes a new methodology of framework reconfigurable assembly systems principles in automotive framing systems i.e. enhance assembly process between side structure assembly and undercarriage assembly which a new RAS is capable to reconfigure the assembly processes of multiple model on a single assembly line. Simulation software (Witness will be used to simulate and validate current and proposed assembly process. RAS is expected to be a solution for rapid change in structure and for a responsively adjustable production capacity. Quality, cost and delivery are production key parameters that can be achieved by implementing RAS.

Ginger Stimulates Hematopoiesis via Bmp Pathway in Zebrafish

Science.gov (United States)

Ferri-Lagneau, Karine F.; Moshal, Karni S.; Grimes, Matthew; Zahora, Braden; Lv, Lishuang; Sang, Shengmin; Leung, TinChung

2012-01-01

Background Anemia is a hematologic disorder with decreased number of erythrocytes. Erythropoiesis, the process by which red blood cells differentiate, are conserved in humans, mice and zebrafish. The only known agents available to treat pathological anemia are erythropoietin and its biologic derivatives. However, erythropoietin therapy elicits unwanted side-effects, high cost and intravenous or subcutaneous injection, warranting the development of a more cost effective and non-peptide alternative. Ginger (Zingiber officinale) has been widely used in traditional medicine; however, to date there is no scientific research documenting the potential of ginger to stimulate hematopoiesis. Methodology/Principal Findings Here, we utilized gata1:dsRed transgenic zebrafish embryos to investigate the effect of ginger extract on hematopoiesis in vivo and we identified its bioactive component, 10-gingerol. We confirmed that ginger and 10-gingerol promote the expression of gata1 in erythroid cells and increase the expression of hematopoietic progenitor markers cmyb and scl. We also demonstrated that ginger and 10-gingerol can promote the hematopoietic recovery from acute hemolytic anemia in zebrafish, by quantifying the number of circulating erythroid cells in the dorsal aorta using video microscopy. We found that ginger and 10-gingerol treatment during gastrulation results in an increase of bmp2b and bmp7a expression, and their downstream effectors, gata2 and eve1. At later stages ginger and 10-gingerol can induce bmp2b/7a, cmyb, scl and lmo2 expression in the caudal hematopoietic tissue area. We further confirmed that Bmp/Smad pathway mediates this hematopoiesis promoting effect of ginger by using the Bmp-activated Bmp type I receptor kinase inhibitors dorsomorphin, LND193189 and DMH1. Conclusions/Significance Our study provides a strong foundation to further evaluate the molecular mechanism of ginger and its bioactive components during hematopoiesis and to investigate their

A Compact Energy Harvesting System for Outdoor Wireless Sensor Nodes Based on a Low-Cost In Situ Photovoltaic Panel Characterization-Modelling Unit.

Science.gov (United States)

Antolín, Diego; Medrano, Nicolás; Calvo, Belén; Martínez, Pedro A

2017-08-04

This paper presents a low-cost high-efficiency solar energy harvesting system to power outdoor wireless sensor nodes. It is based on a Voltage Open Circuit (VOC) algorithm that estimates the open-circuit voltage by means of a multilayer perceptron neural network model trained using local experimental characterization data, which are acquired through a novel low cost characterization system incorporated into the deployed node. Both units-characterization and modelling-are controlled by the same low-cost microcontroller, providing a complete solution which can be understood as a virtual pilot cell, with identical characteristics to those of the specific small solar cell installed on the sensor node, that besides allows an easy adaptation to changes in the actual environmental conditions, panel aging, etc. Experimental comparison to a classical pilot panel based VOC algorithm show better efficiency under the same tested conditions.

Low-Cost Alternative External Rotation Shoulder Brace and Review of Treatment in Acute Shoulder Dislocations

Directory of Open Access Journals (Sweden)

Lacy, Kyle

2015-01-01

Full Text Available Traumatic dislocations of the shoulder commonly present to emergency departments (EDs. Immediate closed reduction of both anterior and posterior glenohumeral dislocations is recommended and is frequently performed in the ED. Recurrence of dislocation is common, as anteroinferior labral tears (Bankart lesions are present in many anterior shoulder dislocations.14,15,18,23 Immobilization of the shoulder following closed reduction is therefore recommended; previous studies support the use of immobilization with the shoulder in a position of external rotation, for both anterior and posterior shoulder dislocations.7-11,19 In this study, we present a technique for assembling a low-cost external rotation shoulder brace using materials found in most hospitals: cotton roll, stockinette, and shoulder immobilizers. This brace is particularly suited for the uninsured patient, who lacks the financial resources to pay for a pre-fabricated brace out of pocket. We also performed a cost analysis for our low-cost external rotation shoulder brace, and a cost comparison with pre-fabricated brand name braces. At our institution, the total materials cost for our brace was $19.15. The cost of a pre-fabricated shoulder brace at our institution is $150 with markup, which is reimbursed on average at $50.40 according to our hospital billing data. The low-cost external rotation shoulder brace is therefore a more affordable option for the uninsured patient presenting with acute shoulder dislocation. [West J Emerg Med. 2015;16(1:114–120.

FishNet: an online database of zebrafish anatomy

Directory of Open Access Journals (Sweden)

Gibson Abigail J

2007-08-01

Full Text Available Abstract Background Over the last two decades, zebrafish have been established as a genetically versatile model system for investigating many different aspects of vertebrate developmental biology. With the credentials of zebrafish as a developmental model now well recognized, the emerging new opportunity is the wider application of zebrafish biology to aspects of human disease modelling. This rapidly increasing use of zebrafish as a model for human disease has necessarily generated interest in the anatomy of later developmental phases such as the larval, juvenile, and adult stages, during which many of the key aspects of organ morphogenesis and maturation take place. Anatomical resources and references that encompass these stages are non-existent in zebrafish and there is therefore an urgent need to understand how different organ systems and anatomical structures develop throughout the life of the fish. Results To overcome this deficit we have utilized the technique of optical projection tomography to produce three-dimensional (3D models of larval fish. In order to view and display these models we have created FishNet http://www.fishnet.org.au, an interactive reference of zebrafish anatomy spanning the range of zebrafish development from 24 h until adulthood. Conclusion FishNet contains more than 36 000 images of larval zebrafish, with more than 1 500 of these being annotated. The 3D models can be manipulated on screen or virtually sectioned. This resource represents the first complete embryo to adult atlas for any species in 3D.

Hormetic effect induced by depleted uranium in zebrafish embryos

International Nuclear Information System (INIS)

Ng, C.Y.P.; Cheng, S.H.; Yu, K.N.

2016-01-01

Highlights: • Studied hormetic effect induced by uranium (U) in embryos of zebrafish (Danio rerio). • Hormesis observed at 24 hpf for exposures to 10 μg/l of depleted U (DU). • Hormesis not observed before 30 hpf for exposures to 100 μg/l of DU. • Hormetic effect induced in zebrafish embryos in a dose-and time-dependent manner. - Abstract: The present work studied the hormetic effect induced by uranium (U) in embryos of zebrafish (Danio rerio) using apoptosis as the biological endpoint. Hormetic effect is characterized by biphasic dose-response relationships showing a low-dose stimulation and a high-dose inhibition. Embryos were dechorionated at 4 h post fertilization (hpf), and were then exposed to 10 or 100 μg/l depleted uranium (DU) in uranyl acetate solutions from 5 to 6 hpf. For exposures to 10 μg/l DU, the amounts of apoptotic signals in the embryos were significantly increased at 20 hpf but were significantly decreased at 24 hpf, which demonstrated the presence of U-induced hormesis. For exposures to 100 μg/l DU, the amounts of apoptotic signals in the embryos were significantly increased at 20, 24 and 30 hpf. Hormetic effect was not shown but its occurrence between 30 and 48 hpf could not be ruled out. In conclusion, hormetic effect could be induced in zebrafish embryos in a concentration- and time-dependent manner.

Hormetic effect induced by depleted uranium in zebrafish embryos

Energy Technology Data Exchange (ETDEWEB)

Ng, C.Y.P. [Department of Physics and Materials Science, City University of Hong Kong (Hong Kong); Cheng, S.H., E-mail: bhcheng@cityu.edu.hk [Department of Biomedical Sciences, City University of Hong Kong (Hong Kong); State Key Laboratory in Marine Pollution, City University of Hong Kong (Hong Kong); Yu, K.N., E-mail: peter.yu@cityu.edu.hk [Department of Physics and Materials Science, City University of Hong Kong (Hong Kong); State Key Laboratory in Marine Pollution, City University of Hong Kong (Hong Kong)

2016-06-15

Highlights: • Studied hormetic effect induced by uranium (U) in embryos of zebrafish (Danio rerio). • Hormesis observed at 24 hpf for exposures to 10 μg/l of depleted U (DU). • Hormesis not observed before 30 hpf for exposures to 100 μg/l of DU. • Hormetic effect induced in zebrafish embryos in a dose-and time-dependent manner. - Abstract: The present work studied the hormetic effect induced by uranium (U) in embryos of zebrafish (Danio rerio) using apoptosis as the biological endpoint. Hormetic effect is characterized by biphasic dose-response relationships showing a low-dose stimulation and a high-dose inhibition. Embryos were dechorionated at 4 h post fertilization (hpf), and were then exposed to 10 or 100 μg/l depleted uranium (DU) in uranyl acetate solutions from 5 to 6 hpf. For exposures to 10 μg/l DU, the amounts of apoptotic signals in the embryos were significantly increased at 20 hpf but were significantly decreased at 24 hpf, which demonstrated the presence of U-induced hormesis. For exposures to 100 μg/l DU, the amounts of apoptotic signals in the embryos were significantly increased at 20, 24 and 30 hpf. Hormetic effect was not shown but its occurrence between 30 and 48 hpf could not be ruled out. In conclusion, hormetic effect could be induced in zebrafish embryos in a concentration- and time-dependent manner.

A Low-Cost Collaborative Location Scheme with GNSS and RFID for the Internet of Things

Directory of Open Access Journals (Sweden)

Changfeng Jing

2018-05-01

Full Text Available The emergence and development of the Internet of Things (IoT has attracted growing attention to low-cost location systems when facing the dramatically increased number of public infrastructure assets in smart cities. Various radio frequency identification (RFID-based locating systems have been developed. However, most of them are impractical for infrastructure asset inspection and management on a large scale due to their high cost, inefficient deployment, and complex environments such as emergencies or high-rise buildings. In this paper, we proposed a novel locating system by combing the Global Navigation Satellite System (GNSS with RFID, in which a target tag was located with one RFID reader and one GNSS receiver with sufficient accuracy for infrastructure asset management. To overcome the cost challenge, one mobile RFID reader-mounted GNSS receiver is used to simulate multiple location known reference tags. A vast number of reference tags are necessary for current RFID-based locating systems, which means higher cost. To achieve fine-grained location accuracy, we utilize a distance-based power law weight algorithm to estimate the exact coordinates. Our experiment demonstrates the effectiveness and advantages of the proposed scheme with sufficient accuracy, low cost and easy deployment on a large scale. The proposed scheme has potential applications for location-based services in smart cities.

Design of a low cost Zimm-Crothers viscometer: From theory to experiment

Science.gov (United States)

Courbin, L.; Cristobal, G.; Winckert, M.; Panizza, P.

2005-09-01

To accurately measure low viscosities of liquids, we describe how a Zimm-Crothers viscometer works and how to build it. The viscometer involves the action of a rotating magnetic field on a metallic cylinder floating on the liquid to be studied. The principles of electromagnetism and fluid mechanics involved make the viscometer an excellent tool for undergraduate laboratory courses and for measuring the shear viscosity of low viscous fluids. We discuss the advantages and limitations of this inexpensive and easy to use apparatus compared to other classical techniques. Calibrations with Newtonian fluids are explained and experiments with Non-Newtonian materials are discussed.

A powerful, low-cost histogramming memory for digital radiography with multi-wire proportional counters

International Nuclear Information System (INIS)

Bateman, J.E.; Locke, C.E.R.; Ferrari, C.A.

1986-01-01

A powerful, low-cost histogramming memory for digital radiograph with multi-wire proportional counter is described. The memory is based on a commercial video display device coupled to an Apple II microcomputer which, at a total cost of around 2500 pounds gives a system with 512 x 512 pixel resolution and a counting range of 4095 counts per pixel. The system can take data at rates of up to 5000 Hz while providing a live-time display. No hardware modifications are necessary, the comprehensive storage and display facilities being implemented in a combined package of BASIC and ASSEMBLER software. An ACCELERATOR coprocessor card is used to enhance the performance of the system. (author)

Effects of low heterogeneity in fast critical assemblies

International Nuclear Information System (INIS)

Belov, S.P.; Dulin, V.A.; Zhukov, A.V.; Kuzin, E.N.; Mozhaev, V.K.; Sitnikov, V.I.; Tsibulya, A.M.; Shapar', A.V.; Zayfert, E.; Kuntsman, B.; Khayntsel'man, B.

1989-01-01

The problem of the low heterogeneity of fast critical assemblies, which are used to simulate fast reactors that are under design, has begun to assume increasing importance as the errors in nuclear data and group constants decrease and the capabilities of design codes improve. The design of the fuel channels of the fast critical assemblies of a BFS differs from that of the fuel subassemblies of a power reactor. The principal difference is that critical assemblies have a more heterogeneous structure than a reactor core does. As a result, the effects of this heterogeneity turn out to be appreciable for a number of functionals. Of particular interest was the measurement of the main neutronic characteristics of a fast reactor in its actual design and in the mockup produced by using BFS facilities. The authors measured and calculated the most important functionals (the ratios of the average cross sections of the main absorbing and fissioning elements, etc.) for both a homogeneous medium (fuel assemblies) and a heterogeneous medium (slugs, tubes) of practically identical composition. The objective of this work was to compare the discrepancy between experiment and calculations for the central functionals in the homogeneous and heterogeneous cases after corrections. This is a check of the accuracy of the simulation of homogeneous cores in fast power reactors by using the tools of the BFS fast critical assembly

Genomic Organization of Zebrafish microRNAs

Directory of Open Access Journals (Sweden)

Paydar Ima

2008-05-01

Full Text Available Abstract Background microRNAs (miRNAs are small (~22 nt non-coding RNAs that regulate cell movement, specification, and development. Expression of miRNAs is highly regulated, both spatially and temporally. Based on direct cloning, sequence conservation, and predicted secondary structures, a large number of miRNAs have been identified in higher eukaryotic genomes but whether these RNAs are simply a subset of a much larger number of noncoding RNA families is unknown. This is especially true in zebrafish where genome sequencing and annotation is not yet complete. Results We analyzed the zebrafish genome to identify the number and location of proven and predicted miRNAs resulting in the identification of 35 new miRNAs. We then grouped all 415 zebrafish miRNAs into families based on seed sequence identity as a means to identify possible functional redundancy. Based on genomic location and expression analysis, we also identified those miRNAs that are likely to be encoded as part of polycistronic transcripts. Lastly, as a resource, we compiled existing zebrafish miRNA expression data and, where possible, listed all experimentally proven mRNA targets. Conclusion Current analysis indicates the zebrafish genome encodes 415 miRNAs which can be grouped into 44 families. The largest of these families (the miR-430 family contains 72 members largely clustered in two main locations along chromosome 4. Thus far, most zebrafish miRNAs exhibit tissue specific patterns of expression.

In silico identification of anthropogenic chemicals as ligands of zebrafish sex hormone binding globulin

International Nuclear Information System (INIS)

Thorsteinson, Nels; Ban, Fuqiang; Santos-Filho, Osvaldo; Tabaei, Seyed M.H.; Miguel-Queralt, Solange; Underhill, Caroline; Cherkasov, Artem; Hammond, Geoffrey L.

2009-01-01

Anthropogenic compounds with the capacity to interact with the steroid-binding site of sex hormone binding globulin (SHBG) pose health risks to humans and other vertebrates including fish. Building on studies of human SHBG, we have applied in silico drug discovery methods to identify potential binders for SHBG in zebrafish (Danio rerio) as a model aquatic organism. Computational methods, including; homology modeling, molecular dynamics simulations, virtual screening, and 3D QSAR analysis, successfully identified 6 non-steroidal substances from the ZINC chemical database that bind to zebrafish SHBG (zfSHBG) with low-micromolar to nanomolar affinities, as determined by a competitive ligand-binding assay. We also screened 80,000 commercial substances listed by the European Chemicals Bureau and Environment Canada, and 6 non-steroidal hits from this in silico screen were tested experimentally for zfSHBG binding. All 6 of these compounds displaced the [ 3 H]5α-dihydrotestosterone used as labeled ligand in the zfSHBG screening assay when tested at a 33 μM concentration, and 3 of them (hexestrol, 4-tert-octylcatechol, and dihydrobenzo(a)pyren-7(8H)-one) bind to zfSHBG in the micromolar range. The study demonstrates the feasibility of large-scale in silico screening of anthropogenic compounds that may disrupt or highjack functionally important protein:ligand interactions. Such studies could increase the awareness of hazards posed by existing commercial chemicals at relatively low cost

Investigation of innovative silicon detector assembling solutions for hadron calorimeter modules

International Nuclear Information System (INIS)

Cai, G.; Ammannati, N.

1995-01-01

The application of large areas of silicon detector mosaics in calorimetry for high energy particles measurement in Physics has grown in the last few years and is still in progress. The high number of mosaic units in the calorimeter implies the following main requirements to be satisfied: a simple low cost for manufacturing and assembling, easy mountable/dismountable units, possibility to move or change silicon detectors easily, reliability of the electrical contacts between the aluminium layer on the silicon detector surface and the PCB breaker points.In order to satisfy the above requirements several assembling solutions have been investigated and tested recently, as fixed contact by using conducting epoxy-glues, mechanically dismountable contacts of gold-plated PCB copper to the silicon detectors, and others.The results of the tests show a general degradation of the original electrical characteristics of the contacts after of varying lengths operating times.This fact, due to corrosion phenomena assisted by chemical residuals in the contact interface, causes an irreversible damage of the detectors in the long term.In addition we found a room temperature interdiffusion of gold and copper.A promising solution to these problems can be achieved by careful removal of chemical, increase of golden layer of the PCB electrical copper contacts or aluminising them by pure aluminium vapour deposition in vacuum chamber.Thee estimated degradation time between the PCB copper and the aluminium film is very low in this case, and the risk of diffusion in the detector aluminium film surface is low along the whole operating life of the calorimeter. (orig.)

CCDC103 mutations cause primary ciliary dyskinesia by disrupting assembly of ciliary dynein arms

Science.gov (United States)

Panizzi, Jennifer R.; Becker-Heck, Anita; Castleman, Victoria H.; Al-Mutairi, Dalal; Liu, Yan; Loges, Niki T.; Pathak, Narendra; Austin-Tse, Christina; Sheridan, Eamonn; Schmidts, Miriam; Olbrich, Heike; Werner, Claudius; Häffner, Karsten; Hellman, Nathan; Chodhari, Rahul; Gupta, Amar; Kramer-Zucker, Albrecht; Olale, Felix; Burdine, Rebecca D.; Schier, Alexander F.; O’Callaghan, Christopher; Chung, Eddie MK; Reinhardt, Richard; Mitchison, Hannah M.; King, Stephen M.; Omran, Heymut; Drummond, Iain A.

2012-01-01

Cilia are essential for fertilization, respiratory clearance, cerebrospinal fluid circulation, and to establish laterality1. Cilia motility defects cause Primary Ciliary Dyskinesia (PCD, MIM 242650), a disorder affecting 1:15-30,000 births. Cilia motility requires the assembly of multisubunit dynein arms that drive cilia bending2. Despite progress in understanding the genetic basis of PCD, mutations remain to be identified for several PCD linked loci3. Here we show that the zebrafish cilia paralysis mutant schmalhanstn222 (smh) mutant encodes the coiled-coil domain containing 103 protein (Ccdc103), a foxj1a regulated gene. Screening 146 unrelated PCD families identified patients in six families with reduced outer dynein arms, carrying mutations in CCDC103. Dynein arm assembly in smh mutant zebrafish was rescued by wild-type but not mutant human CCDC103. Chlamydomonas Ccdc103 functions as a tightly bound, axoneme-associated protein. The results identify Ccdc103 as a novel dynein arm attachment factor that when mutated causes Primary Ciliary Dyskinesia. PMID:22581229

Development of an opioid self-administration assay to study drug seeking in zebrafish.

Science.gov (United States)

Bossé, Gabriel D; Peterson, Randall T

2017-09-29

The zebrafish (Danio rerio) has become an excellent tool to study mental health disorders, due to its physiological and genetic similarity to humans, ease of genetic manipulation, and feasibility of small molecule screening. Zebrafish have been shown to exhibit characteristics of addiction to drugs of abuse in non-contingent assays, including conditioned place preference, but contingent assays have been limited to a single assay for alcohol consumption. Using inexpensive electronic, mechanical, and optical components, we developed an automated opioid self-administration assay for zebrafish, enabling us to measure drug seeking and gain insight into the underlying biological pathways. Zebrafish trained in the assay for five days exhibited robust self-administration, which was dependent on the function of the μ-opioid receptor. In addition, a progressive ratio protocol was used to test conditioned animals for motivation. Furthermore, conditioned fish continued to seek the drug despite an adverse consequence and showed signs of stress and anxiety upon withdrawal of the drug. Finally, we validated our assay by confirming that self-administration in zebrafish is dependent on several of the same molecular pathways as in other animal models. Given the ease and throughput of this assay, it will enable identification of important biological pathways regulating drug seeking and could lead to the development of new therapeutic molecules to treat addiction. Copyright © 2017 Elsevier B.V. All rights reserved.

High Performance, Low Cost Hydrogen Generation from Renewable Energy

Energy Technology Data Exchange (ETDEWEB)

Ayers, Katherine [Proton OnSite; Dalton, Luke [Proton OnSite; Roemer, Andy [Proton OnSite; Carter, Blake [Proton OnSite; Niedzwiecki, Mike [Proton OnSite; Manco, Judith [Proton OnSite; Anderson, Everett [Proton OnSite; Capuano, Chris [Proton OnSite; Wang, Chao-Yang [Penn State University; Zhao, Wei [Penn State University

2014-02-05

Renewable hydrogen from proton exchange membrane (PEM) electrolysis is gaining strong interest in Europe, especially in Germany where wind penetration is already at critical levels for grid stability. For this application as well as biogas conversion and vehicle fueling, megawatt (MW) scale electrolysis is required. Proton has established a technology roadmap to achieve the necessary cost reductions and manufacturing scale up to maintain U.S. competitiveness in these markets. This project represents a highly successful example of the potential for cost reduction in PEM electrolysis, and provides the initial stack design and manufacturing development for Proton’s MW scale product launch. The majority of the program focused on the bipolar assembly, from electrochemical modeling to subscale stack development through prototyping and manufacturing qualification for a large active area cell platform. Feasibility for an advanced membrane electrode assembly (MEA) with 50% reduction in catalyst loading was also demonstrated. Based on the progress in this program and other parallel efforts, H2A analysis shows the status of PEM electrolysis technology dropping below $3.50/kg production costs, exceeding the 2015 target.

Exposure to tributyltin induces endoplasmic reticulum stress and the unfolded protein response in zebrafish.

Science.gov (United States)

Komoike, Yuta; Matsuoka, Masato

2013-10-15

Tributyltin (TBT) is a major marine contaminant and causes endocrine disruption, hepatotoxicity, immunotoxicity, and neurotoxicity. However, the molecular mechanisms underlying the toxicity of TBT have not been fully elucidated. We examined whether exposure to TBT induces the endoplasmic reticulum (ER) stress response in zebrafish, a model organism. Zebrafish-derived BRF41 fibroblast cells were exposed to 0.5 or 1 μM TBT for 0.5-16 h and subsequently lysed and immunoblotted to detect ER stress-related proteins. Zebrafish embryos, grown until 32 h post fertilization (hpf), were exposed to 1 μM TBT for 16 h and used in whole mount in situ hybridization and immunohistochemistry to visualize the expression of ER chaperones and an ER stress-related apoptosis factor. Exposure of the BRF41 cells to TBT caused phosphorylation of the zebrafish homolog of protein kinase RNA-activated-like ER kinase (PERK), eukaryotic translation initiation factor 2 alpha (eIF2α), and inositol-requiring enzyme 1 (IRE1), characteristic splicing of X-box binding protein 1 (XBP1) mRNA, and enhanced expression of activating transcription factor 4 (ATF4) protein. In TBT-exposed zebrafish embryos, ectopic expression of the gene encoding zebrafish homolog of the 78 kDa glucose-regulating protein (GRP78) and gene encoding CCAAT/enhancer-binding protein homologous protein (CHOP) was detected in the precursors of the neuromast, which is a sensory organ for detecting water flow and vibration. Our in vitro and in vivo studies revealed that exposure of zebrafish to TBT induces the ER stress response via activation of both the PERK-eIF2α and IRE1-XBP1 pathways of the unfolded protein response (UPR) in an organ-specific manner. Copyright © 2013 Elsevier B.V. All rights reserved.

Diverse Supramolecular Nanofiber Networks Assembled by Functional Low-Complexity Domains.

Science.gov (United States)

An, Bolin; Wang, Xinyu; Cui, Mengkui; Gui, Xinrui; Mao, Xiuhai; Liu, Yan; Li, Ke; Chu, Cenfeng; Pu, Jiahua; Ren, Susu; Wang, Yanyi; Zhong, Guisheng; Lu, Timothy K; Liu, Cong; Zhong, Chao

2017-07-25

Self-assembling supramolecular nanofibers, common in the natural world, are of fundamental interest and technical importance to both nanotechnology and materials science. Despite important advances, synthetic nanofibers still lack the structural and functional diversity of biological molecules, and the controlled assembly of one type of molecule into a variety of fibrous structures with wide-ranging functional attributes remains challenging. Here, we harness the low-complexity (LC) sequence domain of fused in sarcoma (FUS) protein, an essential cellular nuclear protein with slow kinetics of amyloid fiber assembly, to construct random copolymer-like, multiblock, and self-sorted supramolecular fibrous networks with distinct structural features and fluorescent functionalities. We demonstrate the utilities of these networks in the templated, spatially controlled assembly of ligand-decorated gold nanoparticles, quantum dots, nanorods, DNA origami, and hybrid structures. Owing to the distinguishable nanoarchitectures of these nanofibers, this assembly is structure-dependent. By coupling a modular genetic strategy with kinetically controlled complex supramolecular self-assembly, we demonstrate that a single type of protein molecule can be used to engineer diverse one-dimensional supramolecular nanostructures with distinct functionalities.

Impact of CdSe/ZnS quantum dots on the development of zebrafish embryos

Science.gov (United States)

Lei, Yong; Xiao, Qi; Huang, Shan; Xu, Wansu; Zhang, Zhe; He, Zhike; Liu, Yi; Deng, Fengjiao

2011-12-01

Due to their unique fluorescent characteristics, quantum dots (QDs) have been successfully applied in the fields of biotechnology and medicine, but there is very limited information regarding their biodistribution and chronic toxicity in vivo. In this article, the biological behavior and toxic effects of mercaptoacetic acid-CdSe/ZnS QDs (MAA-QDs) in developing zebrafish embryos were investigated by in vivo tests. The MAA-QDs were introduced into zebrafish through microinjection at early stage. The results showed that the MAA-QDs at certain concentrations influenced the survival of zebrafish embryos, but treated embryos without developmental defects were also observed. MAA-QDs injected into the cytoplasm at the one-cell stage were allocated to progeny blastoderm cells during proliferation and almost never entered the yolk. The formation of notochord and primordial germ cells with normal morphologies was detected in the treated embryos by whole-mount in situ hybridization. Furthermore, traces of the element cadmium were mainly discovered in the tissue of liver and kidney of 3-month-old-treated zebrafish by quantitative assessment with inductively coupled plasma mass spectrometry. Thus, we hypothesized that low concentration MAA-QDs have chronic toxicities when they were delivered into zebrafish organs.

Impact of CdSe/ZnS quantum dots on the development of zebrafish embryos

International Nuclear Information System (INIS)

Lei Yong; Xiao Qi; Huang Shan; Xu Wansu; Zhang Zhe; He Zhike; Liu Yi; Den, Fengjiao

2011-01-01

Due to their unique fluorescent characteristics, quantum dots (QDs) have been successfully applied in the fields of biotechnology and medicine, but there is very limited information regarding their biodistribution and chronic toxicity in vivo. In this article, the biological behavior and toxic effects of mercaptoacetic acid-CdSe/ZnS QDs (MAA-QDs) in developing zebrafish embryos were investigated by in vivo tests. The MAA-QDs were introduced into zebrafish through microinjection at early stage. The results showed that the MAA-QDs at certain concentrations influenced the survival of zebrafish embryos, but treated embryos without developmental defects were also observed. MAA-QDs injected into the cytoplasm at the one-cell stage were allocated to progeny blastoderm cells during proliferation and almost never entered the yolk. The formation of notochord and primordial germ cells with normal morphologies was detected in the treated embryos by whole-mount in situ hybridization. Furthermore, traces of the element cadmium were mainly discovered in the tissue of liver and kidney of 3-month-old-treated zebrafish by quantitative assessment with inductively coupled plasma mass spectrometry. Thus, we hypothesized that low concentration MAA-QDs have chronic toxicities when they were delivered into zebrafish organs.

Arsenic transport by zebrafish aquaglyceroporins

Directory of Open Access Journals (Sweden)

Landfear Scott M

2009-11-01

Full Text Available Abstract Background Arsenic is one of the most ubiquitous toxins and endangers the health of tens of millions of humans worldwide. It is a mainly a water-borne contaminant. Inorganic trivalent arsenic (AsIII is one of the major species that exists environmentally. The transport of AsIII has been studied in microbes, plants and mammals. Members of the aquaglyceroporin family have been shown to actively conduct AsIII and its organic metabolite, monomethylarsenite (MAsIII. However, the transport of AsIII and MAsIII in in any fish species has not been characterized. Results In this study, five members of the aquaglyceroporin family from zebrafish (Danio rerio were cloned, and their ability to transport water, glycerol, and trivalent arsenicals (AsIII and MAsIII and antimonite (SbIII was investigated. Genes for at least seven aquaglyceroporins have been annotated in the zebrafish genome project. Here, five genes which are close homologues to human AQP3, AQP9 and AQP10 were cloned from a zebrafish cDNA preparation. These genes were named aqp3, aqp3l, aqp9a, aqp9b and aqp10 according to their similarities to the corresponding human AQPs. Expression of aqp9a, aqp9b, aqp3, aqp3l and aqp10 in multiple zebrafish organs were examined by RT-PCR. Our results demonstrated that these aquaglyceroporins exhibited different tissue expression. They are all detected in more than one tissue. The ability of these five aquaglyceroporins to transport water, glycerol and the metalloids arsenic and antimony was examined following expression in oocytes from Xenopus leavis. Each of these channels showed substantial glycerol transport at equivalent rates. These aquaglyceroporins also facilitate uptake of inorganic AsIII, MAsIII and SbIII. Arsenic accumulation in fish larvae and in different tissues from adult zebrafish was studied following short-term arsenic exposure. The results showed that liver is the major organ of arsenic accumulation; other tissues such as gill, eye

Boosted TCA cycle enhances survival of zebrafish to Vibrio alginolyticus infection.

Science.gov (United States)

Yang, Man-Jun; Cheng, Zhi-Xue; Jiang, Ming; Zeng, Zao-Hai; Peng, Bo; Peng, Xuan-Xian; Li, Hui

2018-01-01

Vibrio alginolyticus is a waterborne pathogen that infects a wide variety of hosts including fish and human, and the outbreak of this pathogen can cause a huge economic loss in aquaculture. Thus, enhancing host's capability to survive from V. alginolyticus infection is key to fighting infection and this remains still unexplored. In the present study, we established a V. alginolyticus-zebrafish interaction model by which we explored how zebrafish survived from V. alginolyticus infection. We used GC-MS based metabolomic approaches to characterize differential metabolomes between survival and dying zebrafish upon infection. Pattern recognition analysis identified the TCA cycle as the most impacted pathway. The metabolites in the TCA cycle were decreased in the dying host, whereas the metabolites were increased in the survival host. Furthermore, the enzymatic activities of the TCA cycle including pyruvate dehydrogenase (PDH), α-ketoglutaric dehydrogenase (KGDH) and succinate dehydrogenase (SDH) also supported this conclusion. Among the increased metabolites in the TCA cycle, malic acid was the most crucial biomarker for fish survival. Indeed, exogenous malate promoted zebrafish survival in a dose-dependent manner. The corresponding activities of KGDH and SDH were also increased. These results indicate that the TCA cycle is a key pathway responsible for the survival or death in response to infection caused by V. alginolyticus, and highlight the way on development of metabolic modulation to control the infection.

Low cost solar air heater

International Nuclear Information System (INIS)

Gill, R.S.; Singh, Sukhmeet; Singh, Parm Pal

2012-01-01

Highlights: ► Single glazed low cost solar air heater is more efficient during summer while double glazed is better in winter. ► For the same initial investment, low cost solar air heaters collect more energy than packed bed solar air heater. ► During off season low cost solar air heater can be stored inside as it is light in weight. - Abstract: Two low cost solar air heaters viz. single glazed and double glazed were designed, fabricated and tested. Thermocole, ultraviolet stabilised plastic sheet, etc. were used for fabrication to reduce the fabrication cost. These were tested simultaneously at no load and with load both in summer and winter seasons along with packed bed solar air heater using iron chips for absorption of radiation. The initial costs of single glazed and double glazed are 22.8% and 26.8% of the initial cost of packed bed solar air heater of the same aperture area. It was found that on a given day at no load, the maximum stagnation temperatures of single glazed and double glazed solar air heater were 43.5 °C and 62.5 °C respectively. The efficiencies of single glazed, double glazed and packed bed solar air heaters corresponding to flow rate of 0.02 m 3 /s-m 2 were 30.29%, 45.05% and 71.68% respectively in winter season. The collector efficiency factor, heat removal factor based on air outlet temperature and air inlet temperature for three solar air heaters were also determined.

The Nordic Countries Meeting on the Zebrafish as a Model for Development and Disease 2012

Science.gov (United States)

Zetterberg, Henrik

2013-01-01

Abstract The first Nordic Countries Meeting on the Zebrafish as a Model for Development and Disease took place at Karolinska Institutet in Stockholm, November 21–23, 2012. The meeting gathered 130 scientists, students, and company representatives from Iceland, Finland, Norway, Denmark, and Sweden, as well as invited guests and keynote speakers from England, Scotland, Germany, Poland, The Netherlands, Singapore, Japan, and the United States. Presentations covered a wide range of topics, including developmental biology, genetics, evolutionary biology, toxicology, behavioral studies, and disease mechanisms. The need for formal guidance and training in zebrafish housing, husbandry, and health monitoring was recognized, and the meeting expressed its support for the joint working group of the FELASA/COST action BM0804 EuFishBioMed. The decision was made to turn the Nordic meeting into an annual event and create a Nordic network of zebrafish researchers. PMID:23590403

Application of low cost technology for the management of irrgation in organic orchads

Science.gov (United States)

Horcajo, Daniel; Patrícia Prazeres Marques, Karina; Rodríguez Sinobas, Leonor

2014-05-01

Throughout history, humans have cyclically return to their old traditions such as the organic orchards. Nowadays, these have been integrated into the modern cities and could supply fresh vegetables to the daily food improving human health. Organic orchards grow crops without pesticides and artificial fertilizers thus, they are respectful with the environment and guarantee the food's safety . In modern society, the application of new technology is a must, in this case to obtain an efficient irrigation. In order to monitor a proper irrigation and save water and energy, soil water content probes are used to measure soil water content. Among them, capacitive probes ,monitored with a specific data logger, are typically used. Most of them, specially the data loggers, are expensive and in many cases are not used. In this work, we have applied the open hardware Arduino to build and program a low cost datalogger for the programming of irrigation in an experimental organic orchard. Results showed that the application of such as low cost technology, which is easily available in the market and easy to understand, everyone can built and program its own device helping in managing water resources in organic orchards .

Ecological risk study on subacute toxicology experiment of streptomycin wastewater for Zebrafish

Science.gov (United States)

Shi, Qing; Shen, Hongyan

2017-08-01

An exposure experiment was conducted to study the effect of different volume fraction of effluent streptomycin wastewater on the activity of the peroxidase (POD) activity and the malondialdehyde (MDA) content in muscles of Zebrafish for 20 days. The results show that POD activity is significantly induced on the eighth day. POD activities in the muscles of Zebrafish exposed to the streptomycin wastewater of 20% exposure group were significantly different (0.01to that of the control group. The MDA content was the effect of induction-inhibition-induction. The results show that as the value of volume fraction of the streptomycin wastewater increase, the Integreted Biomarker Responses (IBR) increase at first and then decrease. The IBR value of Zebrafish that exposed streptomycin wastewater ranged from 10.42 to 54.26, and the wastewater of 10% exposure group induced the maximum value on the twelve day. The study indicates that low concentration streptomycin wastewater has impacts on the antioxidant defense system and antioxidant ability of Zebrafish.

MESA - A new approach to low cost scientific spacecraft

Science.gov (United States)

Keyes, G. W.; Case, C. M.

1982-09-01

Today, the greatest obstacle to science and exploration in space is its cost. The present investigation is concerned with approaches for reducing this cost. Trends in the scientific spacecraft market are examined, and a description is presented for the MESA space platform concept. The cost drivers are considered, taking into account planning, technical aspects, and business factors. It is pointed out that the primary function of the MESA concept is to provide a satellite system at the lowest possible price. In order to reach this goal an attempt is made to benefit from all of the considered cost drivers. It is to be tried to work with the customer early in the mission analysis stage in order to assist in finding the right compromise between mission cost and return. A three phase contractual arrangement is recommended for MESA platforms. The phases are related to mission feasibility, specification definition, and design and development. Modular kit design promotes flexibility at low cost.

Normal anatomy and histology of the adult zebrafish.

Science.gov (United States)

Menke, Aswin L; Spitsbergen, Jan M; Wolterbeek, Andre P M; Woutersen, Ruud A

2011-08-01

The zebrafish has been shown to be an excellent vertebrate model for studying the roles of specific genes and signaling pathways. The sequencing of its genome and the relative ease with which gene modifications can be performed have led to the creation of numerous human disease models that can be used for testing the potential and the toxicity of new pharmaceutical compounds. Many pharmaceutical companies already use the zebrafish for prescreening purposes. So far, the focus has been on ecotoxicity and the effects on embryonic development, but there is a trend to expand the use of the zebrafish with acute, subchronic, and chronic toxicity studies that are currently still carried out with the more conventional test animals such as rodents. However, before we can fully realize the potential of the zebrafish as an animal model for understanding human development, disease, and toxicology, we must first greatly advance our knowledge of normal zebrafish physiology, anatomy, and histology. To further this knowledge, we describe, in the present article, location and histology of the major zebrafish organ systems with a brief description of their function.

A low-cost multimodal head-mounted display system for neuroendoscopic surgery.

Science.gov (United States)

Xu, Xinghua; Zheng, Yi; Yao, Shujing; Sun, Guochen; Xu, Bainan; Chen, Xiaolei

2018-01-01

With rapid advances in technology, wearable devices as head-mounted display (HMD) have been adopted for various uses in medical science, ranging from simply aiding in fitness to assisting surgery. We aimed to investigate the feasibility and practicability of a low-cost multimodal HMD system in neuroendoscopic surgery. A multimodal HMD system, mainly consisted of a HMD with two built-in displays, an action camera, and a laptop computer displaying reconstructed medical images, was developed to assist neuroendoscopic surgery. With this intensively integrated system, the neurosurgeon could freely switch between endoscopic image, three-dimensional (3D) reconstructed virtual endoscopy images, and surrounding environment images. Using a leap motion controller, the neurosurgeon could adjust or rotate the 3D virtual endoscopic images at a distance to better understand the positional relation between lesions and normal tissues at will. A total of 21 consecutive patients with ventricular system diseases underwent neuroendoscopic surgery with the aid of this system. All operations were accomplished successfully, and no system-related complications occurred. The HMD was comfortable to wear and easy to operate. Screen resolution of the HMD was high enough for the neurosurgeon to operate carefully. With the system, the neurosurgeon might get a better comprehension on lesions by freely switching among images of different modalities. The system had a steep learning curve, which meant a quick increment of skill with it. Compared with commercially available surgical assistant instruments, this system was relatively low-cost. The multimodal HMD system is feasible, practical, helpful, and relatively cost efficient in neuroendoscopic surgery.

Energy Efficiency Improvement and Cost Saving Opportunities for the Vehicle Assembly Industry: An ENERGY STAR Guide for Energy and Plant Managers

Energy Technology Data Exchange (ETDEWEB)

Galitsky, Christina; Galitsky, Christina; Worrell, Ernst

2008-01-01

The motor vehicle industry in the U.S. spends about $3.6 billion on energy annually. In this report, we focus on auto assembly plants. In the U.S., over 70 assembly plants currently produce 13 million cars and trucks each year. In assembly plants, energy expenditures is a relatively small cost factor in the total production process. Still, as manufacturers face an increasingly competitive environment, energy efficiency improvements can provide a means to reduce costs without negatively affecting the yield or the quality of the product. In addition, reducing energy costs reduces the unpredictability associated with variable energy prices in today?s marketplace, which could negatively affect predictable earnings, an important element for publicly-traded companies such as those in the motor vehicle industry. In this report, we first present a summary of the motor vehicle assembly process and energy use. This is followed by a discussion of energy efficiency opportunities available for assembly plants. Where available, we provide specific primary energy savings for each energy efficiency measure based on case studies, as well as references to technical literature. If available, we have listed costs and typical payback periods. We include experiences of assembly plants worldwide with energy efficiency measures reviewed in the report. Our findings suggest that although most motor vehicle companies in the U.S. have energy management teams or programs, there are still opportunities available at individual plants to reduce energy consumption cost effectively. Further research on the economics of the measures for individual assembly plants, as part of an energy management program, is needed to assess the potential impact of selected technologies at these plants.

Forward Genetic Screening Using Behavioral Tests in Zebrafish: A Proof of Concept Analysis of Mutants.

Science.gov (United States)

Gerlai, Robert; Poshusta, Tanya L; Rampersad, Mindy; Fernandes, Yohaan; Greenwood, Tammy M; Cousin, Margot A; Klee, Eric W; Clark, Karl J

2017-01-01

The zebrafish enjoys several advantages over other model organisms. It is small, easy to maintain, prolific, and numerous genetic tools are available for it. For example, forward genetic screens have allowed investigators to identify important genes potentially involved in a variety of functions from embryogenesis to cancer. However, despite its sophisticated behavioral repertoire, behavioral methods have rarely been utilized in forward genetic screens. Here, we employ a two-tiered strategy, a proof of concept study, to explore the feasibility of behavioral screens. We generated mutant lines using transposon-based insertional mutagenesis, allowing us to bias mutant selection with target genes expressed within the brain. Furthermore, we employed an efficient and fast behavioral pre-selection in which we investigated the locomotory response of 5-day post-fertilization old larval fish to hyperosmotic shock. Based on this assay, we selected five lines for our lower throughput secondary adult behavioral screen. The latter screen utilized tests in which computer animated image presentation and video-tracking-based automated quantification of behavior allowed us to compare heterozygous zebrafish with their wild-type siblings on their responses to a variety of stimuli. We found significant mutation induced adult behavioral alterations in 4 out of the 5 lines analyzed, including changes in response to social or fear inducing stimuli, to handling and novelty, or in habituation to novelty. We discuss the pros and cons of behavioral phenotyping and of the use of different forward genetic methods in biomedical research with zebrafish.

Learning and memory in zebrafish larvae

Science.gov (United States)

Roberts, Adam C.; Bill, Brent R.; Glanzman, David L.

2013-01-01

Larval zebrafish possess several experimental advantages for investigating the molecular and neural bases of learning and memory. Despite this, neuroscientists have only recently begun to use these animals to study memory. However, in a relatively short period of time a number of forms of learning have been described in zebrafish larvae, and significant progress has been made toward their understanding. Here we provide a comprehensive review of this progress; we also describe several promising new experimental technologies currently being used in larval zebrafish that are likely to contribute major insights into the processes that underlie learning and memory. PMID:23935566

Fuel assembly design for APR1400 with low CBC

Energy Technology Data Exchange (ETDEWEB)

Hah, Chang Joo, E-mail: changhah@kings.ac.kr [Department of NPP Engineering, KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

2015-04-29

APR 1400 is a PWR (Pressurized Water Reactor) with rated power of 3983 MWth and 241 assemblies. Recently, demand for extremely longer cycle up to 24 months is increasing with challenge of higher critical boron concentration (CBC). In this paper, assembly design method of selecting Gd-rods is introduced to reduce CBC. The purpose of the method is to lower the critical boron concentration of the preliminary core loading pattern (PLP), and consequently to achieve more negative or less positive moderator temperature coefficient (MTC). In this method, both the ratio of the number of low-Gd rod to the number of high-Gd rod (r) and assembly average Gd wt% (w) are the decision variables. The target function is the amount of soluble boron concentration reduction, which can be converted to Δk{sub TARGET}. A set of new designed fuel assembly satisfies an objective function, min [f=∑{sub i}(Δk{sub FA}−Δk{sub i})], and enables a final loading pattern to reach a target CBC. The constraints required to determine a set of Δk are physically realizable pair, (r,w), and the sum of Δk of new designed assemblies as close to Δk{sub TARGET} as possible. New Gd-bearing assemblies selected based on valid pairs of (r,w) are replaced with existing assemblies in a PLP. This design methodology is applied to Shin-Kori Unit 3 Cycle 1 used as a reference model. CASMO-3/MASTER code is used for depletion calculation. CASMO-3/MASTER calculations with new designed assemblies produce lower CBC than the expected CBC, proving that the proposed method works successful.

Zebrafish: A Versatile Animal Model for Fertility Research

Directory of Open Access Journals (Sweden)

Jing Ying Hoo

2016-01-01

Full Text Available The utilization of zebrafish in biomedical research is very common in the research world nowadays. Today, it has emerged as a favored vertebrate organism for the research in science of reproduction. There is a significant growth in amount numbers of scientific literature pertaining to research discoveries in reproductive sciences in zebrafish. It has implied the importance of zebrafish in this particular field of research. In essence, the current available literature has covered from the very specific brain region or neurons of zebrafish, which are responsible for reproductive regulation, until the gonadal level of the animal. The discoveries and findings have proven that this small animal is sharing a very close/similar reproductive system with mammals. More interestingly, the behavioral characteristics and along with the establishment of animal courtship behavior categorization in zebrafish have laid an even stronger foundation and firmer reason on the suitability of zebrafish utilization in research of reproductive sciences. In view of the immense importance of this small animal for the development of reproductive sciences, this review aimed at compiling and describing the proximate close similarity of reproductive regulation on zebrafish and human along with factors contributing to the infertility, showing its versatility and its potential usage for fertility research.

Zebrafish have an ethanol-inducible hepatic 4-nitrophenol hydroxylase that is not CYP2E1-like.

Science.gov (United States)

Hartman, Jessica H; Kozal, Jordan S; Di Giulio, Richard T; Meyer, Joel N

2017-09-01

Zebrafish are an attractive model organism for toxicology; however, an important consideration in translating between species is xenobiotic metabolism/bioactivation. CYP2E1 metabolizes small hydrophobic molecules, e.g. ethanol, cigarette smoke, and diesel exhaust components. CYP2E1 is thought to only be conserved in mammals, but recent reports identified homologous zebrafish cytochrome P450s. Herein, ex vivo biochemical measurements show that unlike mammals, zebrafish possess a low-affinity 4-nitrophenol hydroxylase (K m ∼0.6 mM) in hepatic microsomes and mitochondria that is inducible only 1.5- to 2-fold by ethanol and is insensitive to 4-methylpyrazole inhibition. In closing, we suggest creating improved models to study CYP2E1 in zebrafish. Copyright © 2017 Elsevier B.V. All rights reserved.

The Development of Low-Cost Airlines and Tourism as a Competitiveness Complementor: Effects, Evolution and Strategies

Directory of Open Access Journals (Sweden)

Luis Moreno

2015-12-01

Full Text Available This paper addresses the relationship between the development of the airline industry and tourism. On the one hand, air transport has triggered the growth of tourism throughout the world, while, on the other hand, tourism has acted as a complementary product for developing new flight routes. This process has intensified with the emergence of low-cost carriers. A profound change has been observed in companies’ strategy to adapt to the demands of this type of market. To conduct this study, a review of the existing literature related to tourism and lowcost carriers was carried out. To conclude, an analysis of the positioning and price-fixing strategies of low-cost airlines operating on some of the most important tourist routes in Europe was performed. The results indicate different level of fares among the five companies in the sample, especially between Ryanair and easyJet, but similar pricing behaviour on the routes studied.

A versatile and low-cost open source pipetting robot for automation of toxicological and ecotoxicological bioassays.

Science.gov (United States)

Steffens, Sebastian; Nüßer, Leonie; Seiler, Thomas-Benjamin; Ruchter, Nadine; Schumann, Mark; Döring, Ricarda; Cofalla, Catrina; Ostfeld, Avi; Salomons, Elad; Schüttrumpf, Holger; Hollert, Henner; Brinkmann, Markus

2017-01-01

In the past decades, bioassays and whole-organism bioassay have become important tools not only in compliance testing of industrial chemicals and plant protection products, but also in the monitoring of environmental quality. With few exceptions, such test systems are discontinuous. They require exposure of the biological test material in small units, such as multiwell plates, during prolonged incubation periods, and do not allow online read-outs. It is mostly due to these shortcomings that applications in continuous monitoring of, e.g., drinking or surface water quality are largely missing. We propose the use of pipetting robots that can be used to automatically exchange samples in multiwell plates with fresh samples in a semi-static manner, as a potential solution to overcome these limitations. In this study, we developed a simple and low-cost, versatile pipetting robot constructed partly using open-source hardware that has a small footprint and can be used for online monitoring of water quality by means of an automated whole-organism bioassay. We tested its precision in automated 2-fold dilution series and used it for exposure of zebrafish embryos (Danio rerio)-a common model species in ecotoxicology-to cadmium chloride and permethrin. We found that, compared to conventional static or semi-static exposure scenarios, effects of the two chemicals in zebrafish embryos generally occurred at lower concentrations, and analytically verified that the increased frequency of media exchange resulted in a greater availability of the chemical. In combination with advanced detection systems this custom-made pipetting robot has the potential to become a valuable tool in future monitoring strategies for drinking and surface water.

A versatile and low-cost open source pipetting robot for automation of toxicological and ecotoxicological bioassays.

Directory of Open Access Journals (Sweden)

Sebastian Steffens

Full Text Available In the past decades, bioassays and whole-organism bioassay have become important tools not only in compliance testing of industrial chemicals and plant protection products, but also in the monitoring of environmental quality. With few exceptions, such test systems are discontinuous. They require exposure of the biological test material in small units, such as multiwell plates, during prolonged incubation periods, and do not allow online read-outs. It is mostly due to these shortcomings that applications in continuous monitoring of, e.g., drinking or surface water quality are largely missing. We propose the use of pipetting robots that can be used to automatically exchange samples in multiwell plates with fresh samples in a semi-static manner, as a potential solution to overcome these limitations. In this study, we developed a simple and low-cost, versatile pipetting robot constructed partly using open-source hardware that has a small footprint and can be used for online monitoring of water quality by means of an automated whole-organism bioassay. We tested its precision in automated 2-fold dilution series and used it for exposure of zebrafish embryos (Danio rerio-a common model species in ecotoxicology-to cadmium chloride and permethrin. We found that, compared to conventional static or semi-static exposure scenarios, effects of the two chemicals in zebrafish embryos generally occurred at lower concentrations, and analytically verified that the increased frequency of media exchange resulted in a greater availability of the chemical. In combination with advanced detection systems this custom-made pipetting robot has the potential to become a valuable tool in future monitoring strategies for drinking and surface water.

A Method for Estimating Costs and Benefits of Space Assembly and Servicing By Astronauts and Robots

Science.gov (United States)

Purves, Lloyd R.; Benfield, Mark (Technical Monitor)

2002-01-01

One aspect of designing future space missions is to determine whether Space Assembly and Servicing (SAS) is useful and, if so, what combination of robots and astronauts provides the most effective means of accomplishing it. Certain aspects of these choices, such as the societal value of developing the means for humans to live in space, do not lend themselves to quantification. However, other SAS costs and benefits can be quantified in a manner that can help select the most cost-effective SAS approach. Any space facility, whether it is assembled and serviced or not, entails an eventual replacement cost due to wear and obsolescence. Servicing can reduce this cost by limiting replacement to only failed or obsolete components. However, servicing systems, such as space robots, have their own logistics cost, and astronauts can have even greater logistics requirements. On the other hand, humans can be more capable than robots at performing dexterous and unstructured tasks, which can reduce logistics costs by allowing a reduction in mass of replacement components. Overall, the cost-effectiveness of astronaut SAS depends on its efficiency; and, if astronauts have to be wholly justified by their servicing usefulness, then the serviced space facility has to be large enough to fully occupy them.

Neurotransmitter-Regulated Regeneration in the Zebrafish Retina

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Mahesh B. Rao

2017-04-01

Full Text Available Summary: Current efforts to repair damaged or diseased mammalian retinas are inefficient and largely incapable of fully restoring vision. Conversely, the zebrafish retina is capable of spontaneous regeneration upon damage using Müller glia (MG-derived progenitors. Understanding how zebrafish MG initiate regeneration may help develop new treatments that prompt mammalian retinas to regenerate. We show that inhibition of γ-aminobutyric acid (GABA signaling facilitates initiation of MG proliferation. GABA levels decrease following damage, and MG are positioned to detect decreased ambient levels and undergo dedifferentiation. Using pharmacological and genetic approaches, we demonstrate that GABAA receptor inhibition stimulates regeneration in undamaged retinas while activation inhibits regeneration in damaged retinas. : Unlike mammals, zebrafish regenerate following retina damage from a resident adult stem cell (Müller glia. Dissecting the mechanisms that zebrafish use could lead to new therapeutic targets to treat retinal diseases. Patton and colleagues have discovered a mechanism by which decreased GABA levels are sensed by Müller glia to initiate a regenerative response. Keywords: zebrafish, retina, regeneration, Müller glia, GABA

Miniaturized embryo array for automated trapping, immobilization and microperfusion of zebrafish embryos.

Directory of Open Access Journals (Sweden)

Jin Akagi

Full Text Available Zebrafish (Danio rerio has recently emerged as a powerful experimental model in drug discovery and environmental toxicology. Drug discovery screens performed on zebrafish embryos mirror with a high level of accuracy the tests usually performed on mammalian animal models, and fish embryo toxicity assay (FET is one of the most promising alternative approaches to acute ecotoxicity testing with adult fish. Notwithstanding this, automated in-situ analysis of zebrafish embryos is still deeply in its infancy. This is mostly due to the inherent limitations of conventional techniques and the fact that metazoan organisms are not easily susceptible to laboratory automation. In this work, we describe the development of an innovative miniaturized chip-based device for the in-situ analysis of zebrafish embryos. We present evidence that automatic, hydrodynamic positioning, trapping and long-term immobilization of single embryos inside the microfluidic chips can be combined with time-lapse imaging to provide real-time developmental analysis. Our platform, fabricated using biocompatible polymer molding technology, enables rapid trapping of embryos in low shear stress zones, uniform drug microperfusion and high-resolution imaging without the need of manual embryo handling at various developmental stages. The device provides a highly controllable fluidic microenvironment and post-analysis eleuthero-embryo stage recovery. Throughout the incubation, the position of individual embryos is registered. Importantly, we also for first time show that microfluidic embryo array technology can be effectively used for the analysis of anti-angiogenic compounds using transgenic zebrafish line (fli1a:EGFP. The work provides a new rationale for rapid and automated manipulation and analysis of developing zebrafish embryos at a large scale.

Spreadsheet tool for estimating noise reduction costs

International Nuclear Information System (INIS)

Frank, L.; Senden, V.; Leszczynski, Y.

2009-01-01

The Northeast Capital Industrial Association (NCIA) represents industry in Alberta's industrial heartland. The organization is in the process of developing a regional noise management plan (RNMP) for their member companies. The RNMP includes the development of a noise reduction cost spreadsheet tool to conduct reviews of practical noise control treatments available for individual plant equipment, inclusive of ranges of noise attenuation achievable, which produces a budgetary prediction of the installed cost of practical noise control treatments. This paper discussed the noise reduction cost spreadsheet tool, with particular reference to noise control best practices approaches and spreadsheet tool development such as prerequisite, assembling data required, approach, and unit pricing database. Use and optimization of the noise reduction cost spreadsheet tool was also discussed. It was concluded that the noise reduction cost spreadsheet tool is an easy interactive tool to estimate implementation costs related to different strategies and options of noise control mitigating measures and was very helpful in gaining insight for noise control planning purposes. 2 tabs.

Generating high-quality single droplets for optical particle characterization with an easy setup

Science.gov (United States)

Xu, Jie; Ge, Baozhen; Meng, Rui

2018-06-01

The high-performance and micro-sized single droplet is significant for optical particle characterization. We develop a single-droplet generator (SDG) based on a piezoelectric inkjet technique with advantages of low cost and easy setup. By optimizing the pulse parameters, we achieve various size single droplets. Further investigations reveal that SDG generates single droplets of high quality, demonstrating good sphericity, monodispersity and a stable length of several millimeters.

A dominant negative zebrafish Ahr2 partially protects developing zebrafish from dioxin toxicity.

Directory of Open Access Journals (Sweden)

Kevin A Lanham

Full Text Available The toxicity by 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD is thought to be caused by activation of the aryl hydrocarbon receptor (AHR. However, our understanding of how AHR activation by TCDD leads to toxic effects is poor. Ideally we would like to manipulate AHR activity in specific tissues and at specific times. One route to this is expressing dominant negative AHRs (dnAHRs. This work describes the construction and characterization of dominant negative forms of the zebrafish Ahr2 in which the C-terminal transactivation domain was either removed, or replaced with the inhibitory domain from the Drosophila engrailed repressor protein. One of these dnAhr2s was selected for expression from the ubiquitously active e2fα promoter in transgenic zebrafish. We found that these transgenic zebrafish expressing dnAhr2 had reduced TCDD induction of the Ahr2 target gene cyp1a, as measured by 7-ethoxyresorufin-O-deethylase activity. Furthermore, the cardiotoxicity produced by TCDD, pericardial edema, heart malformation, and reduced blood flow, were all mitigated in the zebrafish expressing the dnAhr2. These results provide in vivo proof-of-principle results demonstrating the effectiveness of dnAHRs in manipulating AHR activity in vivo, and demonstrating that this approach can be a means for blocking TCDD toxicity.

Low energy, low cost, efficient CO{sub 2} capture

Energy Technology Data Exchange (ETDEWEB)

Michael C. Trachtenberg; Lihong Bao; David A. Smith; Remy Dumortier [Carbozyme, Inc., Monmouth Junction, NJ (United States)

2006-07-01

This paper discusses the development and some characteristics of a new, enzyme-based, contained liquid membrane contactor to capture CO{sub 2}. The enzyme carbonic anhydrase catalyzes the removal of CO{sub 2} while the membrane contactor increases the surface area to allow the reduction of the size of the system. The modular system design is easily scaled to any required size reducing the investment costs. The system captures CO{sub 2} at a low energy and low cost promising to be a cost effective technology for CO{sub 2} capture. 5 refs., 7 figs.

Use of zebrafish and knockdown technology to define proprotein convertase activity.

Science.gov (United States)

Chitramuthu, Babykumari P; Bennett, Hugh P J

2011-01-01

The Zebrafish (Danio rerio) is a powerful and well-established tool used extensively for the study of early vertebrate development and as a model of human diseases. Zebrafish genes orthologous to their mammalian counterparts generally share conserved biological function. Protein knockdown or overexpression can be effectively achieved by microinjection of morpholino antisense oligonucleotides (MOs) or mRNA, respectively, into developing embryos at the one- to two-cell stage. Correlating gene expression patterns with the characterizing of phenotypes resulting from over- or underexpression can reveal the function of a particular protein. The microinjection technique is simple and results are reproducible. We defined the expression pattern of the proprotein convertase PCSK5 within the lateral line neuromasts and various organs including the liver, gut and otic vesicle by whole-mount in situ hybridization (ISH) and immunofluorescence (IF). MO-mediated knockdown of zebrafish PCSK5 expression generated embryos that display abnormal neuromast deposition within the lateral line system resulting in uncoordinated patterns of swimming.

Biosecurity and Health Monitoring at the Zebrafish International Resource Center.

Science.gov (United States)

Murray, Katrina N; Varga, Zoltán M; Kent, Michael L

2016-07-01

The Zebrafish International Resource Center (ZIRC) is a repository and distribution center for mutant, transgenic, and wild-type zebrafish. In recent years annual imports of new zebrafish lines to ZIRC have increased tremendously. In addition, after 15 years of research, we have identified some of the most virulent pathogens affecting zebrafish that should be avoided in large production facilities, such as ZIRC. Therefore, while importing a high volume of new lines we prioritize safeguarding the health of our in-house fish colony. Here, we describe the biosecurity and health-monitoring program implemented at ZIRC. This strategy was designed to prevent introduction of new zebrafish pathogens, minimize pathogens already present in the facility, and ensure a healthy zebrafish colony for in-house uses and shipment to customers.

Adaptive locomotor behavior in larval zebrafish.

Science.gov (United States)

Portugues, Ruben; Engert, Florian

2011-01-01

In this study we report that larval zebrafish display adaptive locomotor output that can be driven by unexpected visual feedback. We develop a new assay that addresses visuomotor integration in restrained larval zebrafish. The assay involves a closed-loop environment in which the visual feedback a larva receives depends on its own motor output in a way that resembles freely swimming conditions. The experimenter can control the gain of this closed feedback loop, so that following a given motor output the larva experiences more or less visual feedback depending on whether the gain is high or low. We show that increases and decreases in this gain setting result in adaptive changes in behavior that lead to a generalized decrease or increase of motor output, respectively. Our behavioral analysis shows that both the duration and tail beat frequency of individual swim bouts can be modified, as well as the frequency with which bouts are elicited. These changes can be implemented rapidly, following an exposure to a new gain of just 175 ms. In addition, modifications in some behavioral parameters accumulate over tens of seconds and effects last for at least 30 s from trial to trial. These results suggest that larvae establish an internal representation of the visual feedback expected from a given motor output and that the behavioral modifications are driven by an error signal that arises from the discrepancy between this expectation and the actual visual feedback. The assay we develop presents a unique possibility for studying visuomotor integration using imaging techniques available in the larval zebrafish.

Evaluation in zebrafish model of the toxicity of rhodamine B-conjugated crotamine, a peptide potentially useful for diagnostics and therapeutics.

Science.gov (United States)

Chan, Judy Yuet-Wa; Zhou, Hefeng; Kwan, Yiu Wa; Chan, Shun Wan; Radis-Baptista, Gandhi; Lee, Simon Ming-Yuen

2017-11-01

Crotamine is defensin-like cationic peptide from rattlesnake venom that possesses anticancer, antimicrobial, and antifungal properties. Despite these promising biological activities, toxicity is a major concern associated with the development of venom-derived peptides as therapeutic agents. In the present study, we used zebrafish as a system model to evaluate the toxicity of rhodamine B-conjugated (RhoB) crotamine derivative. The lethal toxic concentration of RhoB-crotamine was as low as 4 μM, which effectively kill zebrafish larvae in less than 10 min. With non-lethal concentrations (<1 μM), crotamine caused malformation in zebrafish embryos, delayed or completely halted hatching, adversely affected embryonic developmental programming, decreased the cardiac functions, and attenuated the swimming distance of zebrafish. The RhoB-crotamine translocated across vitelline membrane and accumulated in zebrafish yolk sac. These results demonstrate the sensitive responsivity of zebrafish to trial crotamine analogues for the development of novel therapeutic peptides with improved safety, bioavailability, and efficacy profiles. © 2017 Wiley Periodicals, Inc.

Optimisation of Embryonic and Larval ECG Measurement in Zebrafish for Quantifying the Effect of QT Prolonging Drugs

Science.gov (United States)

Dhillon, Sundeep Singh; Dóró, Éva; Magyary, István; Egginton, Stuart; Sík, Attila; Müller, Ferenc

2013-01-01

Effective chemical compound toxicity screening is of paramount importance for safe cardiac drug development. Using mammals in preliminary screening for detection of cardiac dysfunction by electrocardiography (ECG) is costly and requires a large number of animals. Alternatively, zebrafish embryos can be used as the ECG waveform is similar to mammals, a minimal amount of chemical is necessary for drug testing, while embryos are abundant, inexpensive and represent replacement in animal research with reduced bioethical concerns. We demonstrate here the utility of pre-feeding stage zebrafish larvae in detection of cardiac dysfunction by electrocardiography. We have optimised an ECG recording system by addressing key parameters such as the form of immobilization, recording temperature, electrode positioning and developmental age. Furthermore, analysis of 3 days post fertilization (dpf) zebrafish embryos treated with known QT prolonging drugs such as terfenadine, verapamil and haloperidol led to reproducible detection of QT prolongation as previously shown for adult zebrafish. In addition, calculation of Z-factor scores revealed that the assay was sensitive and specific enough to detect large drug-induced changes in QTc intervals. Thus, the ECG recording system is a useful drug-screening tool to detect alteration to cardiac cycle components and secondary effects such as heart block and arrhythmias in zebrafish larvae before free feeding stage, and thus provides a suitable replacement for mammalian experimentation. PMID:23579446

Structure of the caspase-recruitment domain from a zebrafish guanylate-binding protein

International Nuclear Information System (INIS)

Jin, Tengchuan; Huang, Mo; Smith, Patrick; Jiang, Jiansheng; Xiao, T. Sam

2013-01-01

The crystal structure of the first zebrafish caspase-recruitment domain at 1.47 Å resolution illustrates a six-helix bundle fold similar to that of the human NLRP1 CARD. The caspase-recruitment domain (CARD) mediates homotypic protein–protein interactions that assemble large oligomeric signaling complexes such as the inflammasomes during innate immune responses. Structural studies of the mammalian CARDs demonstrate that their six-helix bundle folds belong to the death-domain superfamily, whereas such studies have not been reported for other organisms. Here, the zebrafish interferon-induced guanylate-binding protein 1 (zIGBP1) was identified that contains an N-terminal GTPase domain and a helical domain typical of the mammalian guanylate-binding proteins, followed by a FIIND domain and a C-terminal CARD similar to the mammalian inflammasome proteins NLRP1 and CARD8. The structure of the zIGBP1 CARD as a fusion with maltose-binding protein was determined at 1.47 Å resolution. This revealed a six-helix bundle fold similar to the NLRP1 CARD structure with the bent α1 helix typical of all known CARD structures. The zIGBP1 CARD surface contains a positively charged patch near its α1 and α4 helices and a negatively charged patch near its α2, α3 and α5 helices, which may mediate its interaction with partner domains. Further studies using binding assays and other analyses will be required in order to address the physiological function(s) of this zebrafish protein

Directed Assembly of Gold Nanoparticles

DEFF Research Database (Denmark)

Westerlund, Axel Rune Fredrik; Bjørnholm, Thomas

2009-01-01

As a complement to common "top-down" lithography techniques, "bottom-up" assembly techniques are emerging as promising tools to build nanoscale structures in a predictable way. Gold nanoparticles that are stable and relatively easy to synthesize are important building blocks in many such structures...... due to their useful optical and electronic properties. Programmed assembly of gold nanoparticles in one, two, and three dimensions is therefore of large interest. This review focuses on the progress from the last three years in the field of directed gold nanoparticle and nanorod assembly using...

Examination of a Palatogenic Gene Program in Zebrafish

Science.gov (United States)

Swartz, Mary E.; Sheehan-Rooney, Kelly; Dixon, Michael J.; Eberhart, Johann K.

2011-01-01

Human palatal clefting is debilitating and difficult to rectify surgically. Animal models enhance our understanding of palatogenesis and are essential in strategies designed to ameliorate palatal malformations in humans. Recent studies have shown that the zebrafish palate, or anterior neurocranium, is under similar genetic control to the amniote palatal skeleton. We extensively analyzed palatogenesis in zebrafish to determine the similarity of gene expression and function across vertebrates. By 36 hpf palatogenic cranial neural crest cells reside in homologous regions of the developing face compared to amniote species. Transcription factors and signaling molecules regulating mouse palatogenesis are expressed in similar domains during palatogenesis in zebrafish. Functional investigation of a subset of these genes, fgf10a, tgfb2, pax9 and smad5 revealed their necessity in zebrafish palatogenesis. Collectively, these results suggest that the gene regulatory networks regulating palatogenesis may be conserved across vertebrate species, demonstrating the utility of zebrafish as a model for palatogenesis. PMID:22016187

A Lab Assembled Microcontroller-Based Sensor Module for Continuous Oxygen Measurement in Portable Hypoxia Chambers

Science.gov (United States)

Mathupala, Saroj P.; Kiousis, Sam; Szerlip, Nicholas J.

2016-01-01

Background Hypoxia-based cell culture experiments are routine and essential components of in vitro cancer research. Most laboratories use low-cost portable modular chambers to achieve hypoxic conditions for cell cultures, where the sealed chambers are purged with a gas mixture of preset O2 concentration. Studies are conducted under the assumption that hypoxia remains unaltered throughout the 48 to 72 hour duration of such experiments. Since these chambers lack any sensor or detection system to monitor gas-phase O2, the cell-based data tend to be non-uniform due to the ad hoc nature of the experimental setup. Methodology With the availability of low-cost open-source microcontroller-based electronic project kits, it is now possible for researchers to program these with easy-to-use software, link them to sensors, and place them in basic scientific apparatus to monitor and record experimental parameters. We report here the design and construction of a small-footprint kit for continuous measurement and recording of O2 concentration in modular hypoxia chambers. The low-cost assembly (US$135) consists of an Arduino-based microcontroller, data-logging freeware, and a factory pre-calibrated miniature O2 sensor. A small, intuitive software program was written by the authors to control the data input and output. The basic nature of the kit will enable any student in biology with minimal experience in hobby-electronics to assemble the system and edit the program parameters to suit individual experimental conditions. Results/Conclusions We show the kit’s utility and stability of data output via a series of hypoxia experiments. The studies also demonstrated the critical need to monitor and adjust gas-phase O2 concentration during hypoxia-based experiments to prevent experimental errors or failure due to partial loss of hypoxia. Thus, incorporating the sensor-microcontroller module to a portable hypoxia chamber provides a researcher a capability that was previously available

A Lab Assembled Microcontroller-Based Sensor Module for Continuous Oxygen Measurement in Portable Hypoxia Chambers.

Directory of Open Access Journals (Sweden)

Saroj P Mathupala

Full Text Available Hypoxia-based cell culture experiments are routine and essential components of in vitro cancer research. Most laboratories use low-cost portable modular chambers to achieve hypoxic conditions for cell cultures, where the sealed chambers are purged with a gas mixture of preset O2 concentration. Studies are conducted under the assumption that hypoxia remains unaltered throughout the 48 to 72 hour duration of such experiments. Since these chambers lack any sensor or detection system to monitor gas-phase O2, the cell-based data tend to be non-uniform due to the ad hoc nature of the experimental setup.With the availability of low-cost open-source microcontroller-based electronic project kits, it is now possible for researchers to program these with easy-to-use software, link them to sensors, and place them in basic scientific apparatus to monitor and record experimental parameters. We report here the design and construction of a small-footprint kit for continuous measurement and recording of O2 concentration in modular hypoxia chambers. The low-cost assembly (US$135 consists of an Arduino-based microcontroller, data-logging freeware, and a factory pre-calibrated miniature O2 sensor. A small, intuitive software program was written by the authors to control the data input and output. The basic nature of the kit will enable any student in biology with minimal experience in hobby-electronics to assemble the system and edit the program parameters to suit individual experimental conditions.We show the kit's utility and stability of data output via a series of hypoxia experiments. The studies also demonstrated the critical need to monitor and adjust gas-phase O2 concentration during hypoxia-based experiments to prevent experimental errors or failure due to partial loss of hypoxia. Thus, incorporating the sensor-microcontroller module to a portable hypoxia chamber provides a researcher a capability that was previously available only to labs with access to

A Lab Assembled Microcontroller-Based Sensor Module for Continuous Oxygen Measurement in Portable Hypoxia Chambers.

Science.gov (United States)

Mathupala, Saroj P; Kiousis, Sam; Szerlip, Nicholas J

2016-01-01

Hypoxia-based cell culture experiments are routine and essential components of in vitro cancer research. Most laboratories use low-cost portable modular chambers to achieve hypoxic conditions for cell cultures, where the sealed chambers are purged with a gas mixture of preset O2 concentration. Studies are conducted under the assumption that hypoxia remains unaltered throughout the 48 to 72 hour duration of such experiments. Since these chambers lack any sensor or detection system to monitor gas-phase O2, the cell-based data tend to be non-uniform due to the ad hoc nature of the experimental setup. With the availability of low-cost open-source microcontroller-based electronic project kits, it is now possible for researchers to program these with easy-to-use software, link them to sensors, and place them in basic scientific apparatus to monitor and record experimental parameters. We report here the design and construction of a small-footprint kit for continuous measurement and recording of O2 concentration in modular hypoxia chambers. The low-cost assembly (US$135) consists of an Arduino-based microcontroller, data-logging freeware, and a factory pre-calibrated miniature O2 sensor. A small, intuitive software program was written by the authors to control the data input and output. The basic nature of the kit will enable any student in biology with minimal experience in hobby-electronics to assemble the system and edit the program parameters to suit individual experimental conditions. We show the kit's utility and stability of data output via a series of hypoxia experiments. The studies also demonstrated the critical need to monitor and adjust gas-phase O2 concentration during hypoxia-based experiments to prevent experimental errors or failure due to partial loss of hypoxia. Thus, incorporating the sensor-microcontroller module to a portable hypoxia chamber provides a researcher a capability that was previously available only to labs with access to sophisticated (and

The role of adaptive immunity as an ecological filter on the gut microbiota in zebrafish.

Science.gov (United States)

Stagaman, Keaton; Burns, Adam R; Guillemin, Karen; Bohannan, Brendan Jm

2017-07-01

All animals live in intimate association with communities of microbes, collectively referred to as their microbiota. Certain host traits can influence which microbial taxa comprise the microbiota. One potentially important trait in vertebrate animals is the adaptive immune system, which has been hypothesized to act as an ecological filter, promoting the presence of some microbial taxa over others. Here we surveyed the intestinal microbiota of 68 wild-type zebrafish, with functional adaptive immunity, and 61 rag1 - zebrafish, lacking functional B- and T-cell receptors, to test the role of adaptive immunity as an ecological filter on the intestinal microbiota. In addition, we tested the robustness of adaptive immunity's filtering effects to host-host interaction by comparing the microbiota of fish populations segregated by genotype to those containing both genotypes. The presence of adaptive immunity individualized the gut microbiota and decreased the contributions of neutral processes to gut microbiota assembly. Although mixing genotypes led to increased phylogenetic diversity in each, there was no significant effect of adaptive immunity on gut microbiota composition in either housing condition. Interestingly, the most robust effect on microbiota composition was co-housing within a tank. In all, these results suggest that adaptive immunity has a role as an ecological filter of the zebrafish gut microbiota, but it can be overwhelmed by other factors, including transmission of microbes among hosts.

Zebrafish (Danio rerio) behavioural response to bioinspired robotic fish and mosquitofish (Gambusia affinis)

International Nuclear Information System (INIS)

Polverino, Giovanni; Porfiri, Maurizio

2013-01-01

The field of ethorobotics holds promise in aiding fundamental research in animal behaviour, whereby it affords fully controllable and easily reproducible experimental tools. Most of the current ethorobotics studies are focused on the behavioural response of a selected target species as it interacts with a biologically-inspired robot in controlled laboratory conditions. In this work, we first explore the interactions between two social fish species and a robotic fish, whose design is inspired by salient visual features of one of the species. Specifically, this study investigates the behavioural response of small shoals of zebrafish interacting with a zebrafish-inspired robotic fish and small shoals of mosquitofish in a basic ecological context. Our results demonstrate that the robotic fish differentially influences the behaviour of the two species by consistently attracting zebrafish, while repelling mosquitofish. This selective behavioural control is successful in spatially isolating the two species, which would otherwise exhibit prey–predator interactions, with mosquitofish attacking zebrafish. (communication)

Low-Cost Chemical-Responsive Adhesive Sensing Chips.

Science.gov (United States)

Tan, Weirui; Zhang, Liyuan; Shen, Wei

2017-12-06

Chemical-responsive adhesive sensing chip is a new low-cost analytical platform that uses adhesive tape loaded with indicator reagents to detect or quantify the target analytes by directly sticking the tape to the samples of interest. The chemical-responsive adhesive sensing chips can be used with paper to analyze aqueous samples; they can also be used to detect and quantify solid, particulate, and powder analytes. The colorimetric indicators become immediately visible as the contact between the functionalized adhesives and target samples is made. The chemical-responsive adhesive sensing chip expands the capability of paper-based analytical devices to analyze solid, particulate, or powder materials via one-step operation. It is also a simpler alternative way, to the covalent chemical modification of paper, to eliminate indicator leaching from the dipstick-style paper sensors. Chemical-responsive adhesive chips can display analytical results in the form of colorimetric dot patterns, symbols, and texts, enabling clear understanding of assay results by even nonprofessional users. In this work, we demonstrate the analyses of heavy metal salts in silica powder matrix, heavy metal ions in water, and bovine serum albumin in an aqueous solution. The detection is one-step, specific, sensitive, and easy-to-operate.

Low-cost viscometer based on energy dissipation in viscous liquids

Science.gov (United States)

Hashimoto, C.; Cristobal, G.; Nicolas, A.; Panizza, P.; Rouch, J.; Ushiki, H.

2001-04-01

We describe a new type of low-cost easy-to-use viscometer based on the temperature elevation in a liquid under shear flow. After calibration, this instrument can be used to measure the apparent steady state viscosity for both Newtonian and non-Newtonian liquids with no yield stress. We compute the rise in temperature due to viscous dissipation in a Couette cell and compare it to experimental results for different fluids. We show that the variation of the temperature with shear rate can be used to characterize the rheological behaviour of viscous fluids and to evaluate their viscosity in a large domain, from typically a few cP up to more than 10 P, with an accuracy of about ±5%. In contrast to simple viscometers, non-Newtonian fluids can be studied with this apparatus. We give experimental results for Newtonian and non-Newtonian liquids and show that they are very similar to those given in the literature by using much more sophisticated instruments.

Fish can show emotional fever: stress-induced hyperthermia in zebrafish.

Science.gov (United States)

Rey, Sonia; Huntingford, Felicity A; Boltaña, Sebastian; Vargas, Reynaldo; Knowles, Toby G; Mackenzie, Simon

2015-11-22

Whether fishes are sentient beings remains an unresolved and controversial question. Among characteristics thought to reflect a low level of sentience in fishes is an inability to show stress-induced hyperthermia (SIH), a transient rise in body temperature shown in response to a variety of stressors. This is a real fever response, so is often referred to as 'emotional fever'. It has been suggested that the capacity for emotional fever evolved only in amniotes (mammals, birds and reptiles), in association with the evolution of consciousness in these groups. According to this view, lack of emotional fever in fishes reflects a lack of consciousness. We report here on a study in which six zebrafish groups with access to a temperature gradient were either left as undisturbed controls or subjected to a short period of confinement. The results were striking: compared to controls, stressed zebrafish spent significantly more time at higher temperatures, achieving an estimated rise in body temperature of about 2-4°C. Thus, zebrafish clearly have the capacity to show emotional fever. While the link between emotion and consciousness is still debated, this finding removes a key argument for lack of consciousness in fishes. © 2015 The Authors.

Low-Cost Precursors to Novel Hydrogen Storage Materials

International Nuclear Information System (INIS)

Linehan, Suzanne W.; Chin, Arthur A.; Allen, Nathan T.; Butterick, Robert; Kendall, Nathan T.; Klawiter, I. Leo; Lipiecki, Francis J.; Millar, Dean M.; Molzahn, David C.; November, Samuel J.; Jain, Puja; Nadeau, Sara; Mancroni, Scott

2010-01-01

From 2005 to 2010, The Dow Chemical Company (formerly Rohm and Haas Company) was a member of the Department of Energy Center of Excellence on Chemical Hydrogen Storage, which conducted research to identify and develop chemical hydrogen storage materials having the potential to achieve DOE performance targets established for on-board vehicular application. In collaboration with Center co-leads Los Alamos National Laboratory (LANL) and Pacific Northwest National Laboratory (PNNL), and other Center partners, Dow's efforts were directed towards defining and evaluating novel chemistries for producing chemical hydrides and processes for spent fuel regeneration. In Phase 1 of this project, emphasis was placed on sodium borohydride (NaBH 4 ), long considered a strong candidate for hydrogen storage because of its high hydrogen storage capacity, well characterized hydrogen release chemistry, safety, and functionality. Various chemical pathways for regenerating NaBH 4 from spent sodium borate solution were investigated, with the objective of meeting the 2010/2015 DOE targets of $2-3/gal gasoline equivalent at the pump ($2-3/kg H 2 ) for on-board hydrogen storage systems and an overall 60% energy efficiency. With the September 2007 No-Go decision for NaBH 4 as an on-board hydrogen storage medium, focus was shifted to ammonia borane (AB) for on-board hydrogen storage and delivery. However, NaBH 4 is a key building block to most boron-based fuels, and the ability to produce NaBH 4 in an energy-efficient, cost-effective, and environmentally sound manner is critical to the viability of AB, as well as many leading materials under consideration by the Metal Hydride Center of Excellence. Therefore, in Phase 2, research continued towards identifying and developing a single low-cost NaBH4 synthetic route for cost-efficient AB first fill, and conducting baseline cost estimates for first fill and regenerated AB using a variety of synthetic routes. This project utilized an engineering

A Zebrafish Heart Failure Model for Assessing Therapeutic Agents.

Science.gov (United States)

Zhu, Xiao-Yu; Wu, Si-Qi; Guo, Sheng-Ya; Yang, Hua; Xia, Bo; Li, Ping; Li, Chun-Qi

2018-03-20

Heart failure is a leading cause of death and the development of effective and safe therapeutic agents for heart failure has been proven challenging. In this study, taking advantage of larval zebrafish, we developed a zebrafish heart failure model for drug screening and efficacy assessment. Zebrafish at 2 dpf (days postfertilization) were treated with verapamil at a concentration of 200 μM for 30 min, which were determined as optimum conditions for model development. Tested drugs were administered into zebrafish either by direct soaking or circulation microinjection. After treatment, zebrafish were randomly selected and subjected to either visual observation and image acquisition or record videos under a Zebralab Blood Flow System. The therapeutic effects of drugs on zebrafish heart failure were quantified by calculating the efficiency of heart dilatation, venous congestion, cardiac output, and blood flow dynamics. All 8 human heart failure therapeutic drugs (LCZ696, digoxin, irbesartan, metoprolol, qiliqiangxin capsule, enalapril, shenmai injection, and hydrochlorothiazide) showed significant preventive and therapeutic effects on zebrafish heart failure (p failure model developed and validated in this study could be used for in vivo heart failure studies and for rapid screening and efficacy assessment of preventive and therapeutic drugs.

Brain Transcriptomic Response to Social Eavesdropping in Zebrafish (Danio rerio.

Directory of Open Access Journals (Sweden)

João Sollari Lopes

Full Text Available Public information is widely available at low cost to animals living in social groups. For instance, bystanders may eavesdrop on signaling interactions between conspecifics and use it to adapt their subsequent behavior towards the observed individuals. This social eavesdropping ability is expected to require specialized mechanisms such as social attention, which selects social information available for learning. To begin exploring the genetic basis of social eavesdropping, we used a previously established attention paradigm in the lab to study the brain gene expression profile of male zebrafish (Danio rerio in relation to the attention they paid towards conspecifics involved or not involved in agonistic interactions. Microarray gene chips were used to characterize their brain transcriptomes based on differential expression of single genes and gene sets. These analyses were complemented by promoter region-based techniques. Using data from both approaches, we further drafted protein interaction networks. Our results suggest that attentiveness towards conspecifics, whether interacting or not, activates pathways linked to neuronal plasticity and memory formation. The network analyses suggested that fos and jun are key players on this response, and that npas4a, nr4a1 and egr4 may also play an important role. Furthermore, specifically observing fighting interactions further triggered pathways associated to a change in the alertness status (dnajb5 and to other genes related to memory formation (btg2, npas4b, which suggests that the acquisition of eavesdropped information about social relationships activates specific processes on top of those already activated just by observing conspecifics.

DNA controlled assembly of liposomes

DEFF Research Database (Denmark)

Vogel, Stefan; Jakobsen, Ulla; Simonsen, Adam Cohen

2009-01-01

DNA-encoding of solid nanoparticles requires surfacechemistry, which is often tedious and not generally applicable. In the present study non-covalently attached DNA are used to assemble soft nanoparticles (liposomes) in solution. This process displays remarkably sharp thermal transitions from...... assembled to disassembled state for which reason this method allows easy and fast detection of polynucleotides (e.g. DNA or RNA), including single nucleotide polymorphisms as well as insertions and deletions....

Development and evaluation of a low-cost and high-capacity DICOM image data storage system for research.

Science.gov (United States)

Yakami, Masahiro; Ishizu, Koichi; Kubo, Takeshi; Okada, Tomohisa; Togashi, Kaori

2011-04-01

Thin-slice CT data, useful for clinical diagnosis and research, is now widely available but is typically discarded in many institutions, after a short period of time due to data storage capacity limitations. We designed and built a low-cost high-capacity Digital Imaging and COmmunication in Medicine (DICOM) storage system able to store thin-slice image data for years, using off-the-shelf consumer hardware components, such as a Macintosh computer, a Windows PC, and network-attached storage units. "Ordinary" hierarchical file systems, instead of a centralized data management system such as relational database, were adopted to manage patient DICOM files by arranging them in directories enabling quick and easy access to the DICOM files of each study by following the directory trees with Windows Explorer via study date and patient ID. Software used for this system was open-source OsiriX and additional programs we developed ourselves, both of which were freely available via the Internet. The initial cost of this system was about $3,600 with an incremental storage cost of about $900 per 1 terabyte (TB). This system has been running since 7th Feb 2008 with the data stored increasing at the rate of about 1.3 TB per month. Total data stored was 21.3 TB on 23rd June 2009. The maintenance workload was found to be about 30 to 60 min once every 2 weeks. In conclusion, this newly developed DICOM storage system is useful for research due to its cost-effectiveness, enormous capacity, high scalability, sufficient reliability, and easy data access.

Low-cost carriers fare competition effect

NARCIS (Netherlands)

Carmona Benitez, R.B.; Lodewijks, G.

2010-01-01

This paper examines the effects that low-cost carriers (LCC’s) produce when entering new routes operated only by full-service carriers (FSC’s) and routes operated by low-cost carriers in competition with full-service carriers. A mathematical model has been developed to determine what routes should

Near-Net Shape Fabrication Using Low-Cost Titanium Alloy Powders

Energy Technology Data Exchange (ETDEWEB)

Dr. David M. Bowden; Dr. William H. Peter

2012-03-31

The use of titanium in commercial aircraft production has risen steadily over the last half century. The aerospace industry currently accounts for 58% of the domestic titanium market. The Kroll process, which has been used for over 50 years to produce titanium metal from its mineral form, consumes large quantities of energy. And, methods used to convert the titanium sponge output of the Kroll process into useful mill products also require significant energy resources. These traditional approaches result in product forms that are very expensive, have long lead times of up to a year or more, and require costly operations to fabricate finished parts. Given the increasing role of titanium in commercial aircraft, new titanium technologies are needed to create a more sustainable manufacturing strategy that consumes less energy, requires less material, and significantly reduces material and fabrication costs. A number of emerging processes are under development which could lead to a breakthrough in extraction technology. Several of these processes produce titanium alloy powder as a product. The availability of low-cost titanium powders may in turn enable a more efficient approach to the manufacture of titanium components using powder metallurgical processing. The objective of this project was to define energy-efficient strategies for manufacturing large-scale titanium structures using these low-cost powders as the starting material. Strategies include approaches to powder consolidation to achieve fully dense mill products, and joining technologies such as friction and laser welding to combine those mill products into near net shape (NNS) preforms for machining. The near net shape approach reduces material and machining requirements providing for improved affordability of titanium structures. Energy and cost modeling was used to define those approaches that offer the largest energy savings together with the economic benefits needed to drive implementation. Technical

Low-Cost Spectral Sensor Development Description.

Energy Technology Data Exchange (ETDEWEB)

Armijo, Kenneth Miguel; Yellowhair, Julius

2014-11-01

Solar spectral data for all parts of the US is limited due in part to the high cost of commercial spectrometers. Solar spectral information is necessary for accurate photovoltaic (PV) performance forecasting, especially for large utility-scale PV installations. A low-cost solar spectral sensor would address the obstacles and needs. In this report, a novel low-cost, discrete- band sensor device, comprised of five narrow-band sensors, is described. The hardware is comprised of commercial-off-the-shelf components to keep the cost low. Data processing algorithms were developed and are being refined for robustness. PV module short-circuit current ( I sc ) prediction methods were developed based on interaction-terms regression methodology and spectrum reconstruction methodology for computing I sc . The results suggest the computed spectrum using the reconstruction method agreed well with the measured spectrum from the wide-band spectrometer (RMS error of 38.2 W/m 2 -nm). Further analysis of computed I sc found a close correspondence of 0.05 A RMS error. The goal is for ubiquitous adoption of the low-cost spectral sensor in solar PV and other applications such as weather forecasting.

The zebrafish genome: a review and msx gene case study.

Science.gov (United States)

Postlethwait, J H

2006-01-01

Zebrafish is one of several important teleost models for understanding principles of vertebrate developmental, molecular, organismal, genetic, evolutionary, and genomic biology. Efficient investigation of the molecular genetic basis of induced mutations depends on knowledge of the zebrafish genome. Principles of zebrafish genomic analysis, including gene mapping, ortholog identification, conservation of syntenies, genome duplication, and evolution of duplicate gene function are discussed here using as a case study the zebrafish msxa, msxb, msxc, msxd, and msxe genes, which together constitute zebrafish orthologs of tetrapod Msx1, Msx2, and Msx3. Genomic analysis suggests orthologs for this difficult to understand group of paralogs.

Low-cost zinc-plated photoanode for fabric-type dye-sensitized solar cells

Science.gov (United States)

Kong, Lingfeng; Bao, Yunna; Guo, Wanwan; Cheng, Li; Du, Jun; Liu, Renlong; Wang, Yundong; Fan, Xing; Tao, Changyuan

2016-02-01

Fabric-type flexible solar cells have been recently proposed as a very promising power source for wearable electronics. To increase the photocurrent of fabric-type flexible solar cells, low-cost zinc-plated wire and mesh photoanodes are assembled for the first time through a mild wet process. Given the protection of the compact protection layer, the DSSC device could benefit from the low work function of Zn and self-repairing behavior on the Zn/ZnO interface. An evident current increase by ∼6 mA/cm2 could be observed after coating a layer of metal Zn on various metal substrates, such as traditional stainless steel wire. Given the self-repairing behavior on Zn/ZnO interface, the Zn layer can help to improve the interfacial carrier transfer, leading to better photovoltaic performance, for both liquid-type and solid-type cells.

Mutations in LRRC50 predispose zebrafish and humans to seminomas.

Directory of Open Access Journals (Sweden)

Sander G Basten

2013-04-01

Full Text Available Seminoma is a subclass of human testicular germ cell tumors (TGCT, the most frequently observed cancer in young men with a rising incidence. Here we describe the identification of a novel gene predisposing specifically to seminoma formation in a vertebrate model organism. Zebrafish carrying a heterozygous nonsense mutation in Leucine-Rich Repeat Containing protein 50 (lrrc50 also called dnaaf1, associated previously with ciliary function, are found to be highly susceptible to the formation of seminomas. Genotyping of these zebrafish tumors shows loss of heterozygosity (LOH of the wild-type lrrc50 allele in 44.4% of tumor samples, correlating with tumor progression. In humans we identified heterozygous germline LRRC50 mutations in two different pedigrees with a family history of seminomas, resulting in a nonsense Arg488* change and a missense Thr590Met change, which show reduced expression of the wild-type allele in seminomas. Zebrafish in vivo complementation studies indicate the Thr590Met to be a loss-of-function mutation. Moreover, we show that a pathogenic Gln307Glu change is significantly enriched in individuals with seminoma tumors (13% of our cohort. Together, our study introduces an animal model for seminoma and suggests LRRC50 to be a novel tumor suppressor implicated in human seminoma pathogenesis.

Design, construction and commissioning of a simple, low cost permanent magnet quadrupole doublet

International Nuclear Information System (INIS)

Conard, E.M.; Parcell, S.K.; Arnott, D.W.

1999-01-01

In the framework of new beam line developments at the Australian National Medical Cyclotron, a permanent magnet quadrupole doublet was designed and built entirely in house. The design proceeded from the classical work by Halbach et al. but emphasised the 'low cost' aspect by using simple rectangular NdFeB blocks and simple assembly techniques. Numerical simulations using the (2-D) Gemini code were performed to check the field strength and homogeneity predictions of analytical calculations. This paper gives the reasons for the selection of a permanent magnet, the design and construction details of the quadrupole doublet and its field measurement results. (authors)

Neurobehavioral impairments caused by developmental imidacloprid exposure in zebrafish.

Science.gov (United States)

Crosby, Emily B; Bailey, Jordan M; Oliveri, Anthony N; Levin, Edward D

2015-01-01

Neonicotinoid insecticides are becoming more widely applied as organophosphate (OP) insecticides are decreasing in use. Because of their relative specificity to insect nicotinic receptors, they are thought to have reduced risk of neurotoxicity in vertebrates. However, there is scant published literature concerning the neurobehavioral effects of developmental exposure of vertebrates to neonicotinoids. Using zebrafish, we investigated the neurobehavioral effects of developmental exposure to imidacloprid, a prototypic neonicotinoid pesticide. Nicotine was also administered for comparison. Zebrafish were exposed via immersion in aqueous solutions containing 45 μM or 60 μM of imidacloprid or nicotine (or vehicle control) from 4h to 5d post fertilization. The functional effects of developmental exposure to both imidacloprid and nicotine were assessed in larvae using an activity assay and during adolescence and adulthood using a battery of neurobehavioral assays, including assessment of sensorimotor response and habituation in a tactile startle test, novel tank swimming, and shoaling behavior. In larvae, developmental imidacloprid exposure at both doses significantly decreased swimming activity. The 5D strains of zebrafish were more sensitive to both nicotine and imidacloprid than the AB* strain. In adolescent and adult fish, developmental exposure to imidacloprid significantly decreased novel tank exploration and increased sensorimotor response to startle stimuli. While nicotine did not affect novel tank swimming, it increased sensorimotor response to startle stimuli at the low dose. No effects of either compound were found on shoaling behavior or habituation to a startling stimulus. Early developmental exposure to imidacloprid has both early-life and persisting effects on neurobehavioral function in zebrafish. Its developmental neurotoxicity should be further investigated. Copyright © 2015 Elsevier Inc. All rights reserved.

Zebrafish models for the functional genomics of neurogenetic disorders.

Science.gov (United States)

Kabashi, Edor; Brustein, Edna; Champagne, Nathalie; Drapeau, Pierre

2011-03-01

In this review, we consider recent work using zebrafish to validate and study the functional consequences of mutations of human genes implicated in a broad range of degenerative and developmental disorders of the brain and spinal cord. Also we present technical considerations for those wishing to study their own genes of interest by taking advantage of this easily manipulated and clinically relevant model organism. Zebrafish permit mutational analyses of genetic function (gain or loss of function) and the rapid validation of human variants as pathological mutations. In particular, neural degeneration can be characterized at genetic, cellular, functional, and behavioral levels. Zebrafish have been used to knock down or express mutations in zebrafish homologs of human genes and to directly express human genes bearing mutations related to neurodegenerative disorders such as spinal muscular atrophy, ataxia, hereditary spastic paraplegia, amyotrophic lateral sclerosis (ALS), epilepsy, Huntington's disease, Parkinson's disease, fronto-temporal dementia, and Alzheimer's disease. More recently, we have been using zebrafish to validate mutations of synaptic genes discovered by large-scale genomic approaches in developmental disorders such as autism, schizophrenia, and non-syndromic mental retardation. Advances in zebrafish genetics such as multigenic analyses and chemical genetics now offer a unique potential for disease research. Thus, zebrafish hold much promise for advancing the functional genomics of human diseases, the understanding of the genetics and cell biology of degenerative and developmental disorders, and the discovery of therapeutics. This article is part of a Special Issue entitled Zebrafish Models of Neurological Diseases. Copyright © 2010 Elsevier B.V. All rights reserved.

COMPARISON BETWEEN RGB AND RGB-D CAMERAS FOR SUPPORTING LOW-COST GNSS URBAN NAVIGATION

Directory of Open Access Journals (Sweden)

L. Rossi

2018-05-01

Full Text Available A pure GNSS navigation is often unreliable in urban areas because of the presence of obstructions, thus preventing a correct reception of the satellite signal. The bridging between GNSS outages, as well as the vehicle attitude reconstruction, can be recovered by using complementary information, such as visual data acquired by RGB-D or RGB cameras. In this work, the possibility of integrating low-cost GNSS and visual data by means of an extended Kalman filter has been investigated. The focus is on the comparison between the use of RGB-D or RGB cameras. In particular, a Microsoft Kinect device (second generation and a mirrorless Canon EOS M RGB camera have been compared. The former is an interesting RGB-D camera because of its low-cost, easiness of use and raw data accessibility. The latter has been selected for the high-quality of the acquired images and for the possibility of mounting fixed focal length lenses with a lower weight and cost with respect to a reflex camera. The designed extended Kalman filter takes as input the GNSS-only trajectory and the relative orientation between subsequent pairs of images. Depending on the visual data acquisition system, the filter is different because RGB-D cameras acquire both RGB and depth data, allowing to solve the scale problem, which is instead typical of image-only solutions. The two systems and filtering approaches were assessed by ad-hoc experimental tests, showing that the use of a Kinect device for supporting a u-blox low-cost receiver led to a trajectory with a decimeter accuracy, that is 15 % better than the one obtained when using the Canon EOS M camera.

Removal of the precursors of N-nitrosodiethylamine (NDEA), an emerging disinfection byproduct, in drinking water treatment process and its toxicity to adult zebrafish (Danio rerio).

Science.gov (United States)

Zheng, Jian; Lin, Tao; Chen, Wei

2018-01-01

N-nitrosodiethylamine (NDEA) is one of the emerging nitrogenous disinfection byproducts with probable cytotoxicity, genotoxicity, and carcinogenesis. Its potential toxicological effects have received extensive attention but remain to be poorly understood. In this study, changes in NDEA precursors in drinking water treatment process were studied using the trial of its formation potential (FP), and the toxicity induced by NDEA to adult zebrafish was investigated. NDEA FP in the raw water of Taihu Lake ranged from 46.9 to 68.3 ng/L. The NDEA precursors were removed effectively by O 3 /BAC process. Hydrophilic fraction and low-molecular-weight fraction (stress and antioxidant defense to zebrafish metabolism system at concentrations over 5 μg/L. After a 42-day exposure, a significant DNA damage was observed in zebrafish liver cells at NDEA concentrations beyond 500 μg/L. This study investigated NDEA properties in both engineering prospective and toxicity evaluation, thus providing comprehensive information on its control in drinking water treatment process and its toxicity effect on zebrafish as a model animal. Copyright © 2017 Elsevier Ltd. All rights reserved.

Detection of vitellogenin incorporation into zebrafish oocytes by FITC fluorescence

Directory of Open Access Journals (Sweden)

Yokoi Hayato

2011-04-01

Full Text Available Abstract Background Large volumes of lymph can be collected from the eye-sacs of bubble-eye goldfish. We attempted to induce vitellogenin (Vtg in the eye-sac lymph of bubble-eye goldfish and develop a method for visualizing Vtg incorporation by zebrafish oocytes using FITC-labeling. Methods Estrogen efficiently induced Vtg in the eye-sac lymph of goldfish. After FITC-labeled Vtg was prepared, it was injected into mature female zebrafish. Results Incorporation of FITC-labeled Vtg by zebrafish oocytes was detected in in vivo and in vitro experiments. The embryos obtained from zebrafish females injected with FITC-labeled Vtg emitted FITC fluorescence from the yolk sac and developed normally. Conclusion This method for achieving Vtg incorporation by zebrafish oocytes could be useful in experiments related to the development and endocrinology of zebrafish oocytes.

All solution-processed micro-structured flexible electrodes for low-cost light-emitting pressure sensors fabrication.

Science.gov (United States)

Shimotsu, Rie; Takumi, Takahiro; Vohra, Varun

2017-07-31

Recent studies have demonstrated the advantage of developing pressure-sensitive devices with light-emitting properties for direct visualization of pressure distribution, potential application to next generation touch panels and human-machine interfaces. To ensure that this technology is available to everyone, its production cost should be kept as low as possible. Here, simple device concepts, namely, pressure sensitive flexible hybrid electrodes and OLED architecture, are used to produce low-cost resistive or light-emitting pressure sensors. Additionally, integrating solution-processed self-assembled micro-structures into the flexible hybrid electrodes composed of an elastomer and conductive materials results in enhanced device performances either in terms of pressure or spatial distribution sensitivity. For instance, based on the pressure applied, the measured values for the resistances of pressure sensors range from a few MΩ down to 500 Ω. On the other hand, unlike their evaporated equivalents, the combination of solution-processed flexible electrodes with an inverted OLED architectures display bright green emission when a pressure over 200 kPa is applied. At a bias of 3 V, their luminance can be tuned by applying a higher pressure of 500 kPa. Consequently, features such as fingernails and fingertips can be clearly distinguished from one another in these long-lasting low-cost devices.

Zebrafish models in neuropsychopharmacology and CNS drug discovery.

Science.gov (United States)

Khan, Kanza M; Collier, Adam D; Meshalkina, Darya A; Kysil, Elana V; Khatsko, Sergey L; Kolesnikova, Tatyana; Morzherin, Yury Yu; Warnick, Jason E; Kalueff, Allan V; Echevarria, David J

2017-07-01

Despite the high prevalence of neuropsychiatric disorders, their aetiology and molecular mechanisms remain poorly understood. The zebrafish (Danio rerio) is increasingly utilized as a powerful animal model in neuropharmacology research and in vivo drug screening. Collectively, this makes zebrafish a useful tool for drug discovery and the identification of disordered molecular pathways. Here, we discuss zebrafish models of selected human neuropsychiatric disorders and drug-induced phenotypes. As well as covering a broad range of brain disorders (from anxiety and psychoses to neurodegeneration), we also summarize recent developments in zebrafish genetics and small molecule screening, which markedly enhance the disease modelling and the discovery of novel drug targets. © 2017 The British Pharmacological Society.

Evaluation of visible implant elastomer tags in zebrafish (Danio rerio

Directory of Open Access Journals (Sweden)

Claudia Hohn

2013-11-01

The use of the visible implant elastomer (VIE tagging system in zebrafish (Danio rerio was examined. Two tag orientations (horizontal and vertical at the dorsal fin base were tested for tag retention, tag fragmentation and whether VIE tags affected growth and survival of juvenile zebrafish (1–4 month post hatch. Six tag locations (abdomen, anal fin base, caudal peduncle, dorsal fin base, pectoral fin base, isthmus and 5 tag colors (yellow, red, pink, orange, blue were evaluated for ease of VIE tag application and tag visibility in adult zebrafish. Long-term retention (1 year and multiple tagging sites (right and left of dorsal fin and pectoral fin base were examined in adult zebrafish. Lastly, survival of recombination activation gene 1−/− (rag1−/− zebrafish was evaluated after VIE tagging. The best tag location was the dorsal fin base, and the most visible tag color was pink. Growth rate of juvenile zebrafish was not affected by VIE tagging. Horizontal tagging is recommended in early stages of fish growth (1–2 months post hatch. VIE tags were retained for 1 year and tagging did not interfere with long-term growth and survival. There was no mortality associated with VIE tagging in rag1−/− zebrafish. The VIE tagging system is highly suitable for small-sized zebrafish. When familiar with the procedure, 120 adult zebrafish can be tagged in one hour. It does not increase mortality in adult zebrafish or interfere with growth in juvenile or adult zebrafish.

Biosecurity and Health Monitoring at the Zebrafish International Resource Center

OpenAIRE

Murray, Katrina N.; Varga, Zolt?n M.; Kent, Michael L.

2016-01-01

The Zebrafish International Resource Center (ZIRC) is a repository and distribution center for mutant, transgenic, and wild-type zebrafish. In recent years annual imports of new zebrafish lines to ZIRC have increased tremendously. In addition, after 15 years of research, we have identified some of the most virulent pathogens affecting zebrafish that should be avoided in large production facilities, such as ZIRC. Therefore, while importing a high volume of new lines we prioritize safeguarding ...

Two low coverage bird genomes and a comparison of reference-guided versus de novo genome assemblies.

Science.gov (United States)

Card, Daren C; Schield, Drew R; Reyes-Velasco, Jacobo; Fujita, Matthew K; Andrew, Audra L; Oyler-McCance, Sara J; Fike, Jennifer A; Tomback, Diana F; Ruggiero, Robert P; Castoe, Todd A

2014-01-01

As a greater number and diversity of high-quality vertebrate reference genomes become available, it is increasingly feasible to use these references to guide new draft assemblies for related species. Reference-guided assembly approaches may substantially increase the contiguity and completeness of a new genome using only low levels of genome coverage that might otherwise be insufficient for de novo genome assembly. We used low-coverage (∼3.5-5.5x) Illumina paired-end sequencing to assemble draft genomes of two bird species (the Gunnison Sage-Grouse, Centrocercus minimus, and the Clark's Nutcracker, Nucifraga columbiana). We used these data to estimate de novo genome assemblies and reference-guided assemblies, and compared the information content and completeness of these assemblies by comparing CEGMA gene set representation, repeat element content, simple sequence repeat content, and GC isochore structure among assemblies. Our results demonstrate that even lower-coverage genome sequencing projects are capable of producing informative and useful genomic resources, particularly through the use of reference-guided assemblies.

Two low coverage bird genomes and a comparison of reference-guided versus de novo genome assemblies

Science.gov (United States)

Card, Daren C.; Schield, Drew R.; Reyes-Velasco, Jacobo; Fujita, Matthre K.; Andrew, Audra L.; Oyler-McCance, Sara J.; Fike, Jennifer A.; Tomback, Diana F.; Ruggiero, Robert P.; Castoe, Todd A.

2014-01-01

As a greater number and diversity of high-quality vertebrate reference genomes become available, it is increasingly feasible to use these references to guide new draft assemblies for related species. Reference-guided assembly approaches may substantially increase the contiguity and completeness of a new genome using only low levels of genome coverage that might otherwise be insufficient for de novo genome assembly. We used low-coverage (~3.5–5.5x) Illumina paired-end sequencing to assemble draft genomes of two bird species (the Gunnison Sage-Grouse, Centrocercus minimus, and the Clark's Nutcracker, Nucifraga columbiana). We used these data to estimate de novo genome assemblies and reference-guided assemblies, and compared the information content and completeness of these assemblies by comparing CEGMA gene set representation, repeat element content, simple sequence repeat content, and GC isochore structure among assemblies. Our results demonstrate that even lower-coverage genome sequencing projects are capable of producing informative and useful genomic resources, particularly through the use of reference-guided assemblies.

Approach to Assessing the Long-term Performance of Wall Assemblies – Durability of Low-rise Wood-frame walls

DEFF Research Database (Denmark)

Lacasse, Michael A.; Morelli, Martin

2017-01-01

a limit-states design (LSD) approach to the performance assessment of the assembly. In this paper emphasis is placed on a further development of the LSD approach within the context of requirements set out in ISO 13823 “General principles on the design of structures for durability”. An example is presented...... in which the LSD approach is applied to low-rise wood-frame walls, as are built in North America, and that incorporate drainage components, such components forming part of a rain screen wall assembly. The use of this approach permits determining whether wall assemblies incorporating novel components...

Low cost tooling material and process for graphite and Kevlar composites

Science.gov (United States)

Childs, William I.

1987-01-01

An Extruded Sheet Tooling Compound (ESTC) was developed for use in quickly building low cost molds for fabricating composites. The ESTC is a very highly mineral-filled resin system formed into a 6 mm thick sheet. The sheet is laid on the pattern, vacuum (bag) is applied to remove air from the pattern surface, and the assembly is heat cured. The formed ESTC is then backed and/or framed and ready for use. The cured ESTC exhibits low coefficient of thermal expansion and maintains strength at temperatures of 180 to 200 C. Tools were made and used successfully for: Compression molding of high strength epoxy sheet molding compound, stamping of aluminum, resin transfer molding of polyester, and liquid resin molding of polyester. Several variations of ESTC can be made for specific requirements. Higher thermal conductivity can be achieved by using an aluminum particle filler. Room temperature gel is possible to allow use of foam patterns.

low-cost apparatus from locally available materials for teaching

African Journals Online (AJOL)

unesco

twofold: i) to design and produce appropriate low cost apparatus from locally .... How are the low-cost and manufactured apparatus compared in terms of cost and efficiency? ... BASIC TOOLS FOR THE LOW COST APPARATUS PRODUCTION.

In Vitro Biotransformation of Two Human CYP3A Probe Substrates and Their Inhibition during Early Zebrafish Development.

Science.gov (United States)

Verbueken, Evy; Alsop, Derek; Saad, Moayad A; Pype, Casper; Van Peer, Els M; Casteleyn, Christophe R; Van Ginneken, Chris J; Wilson, Joanna; Van Cruchten, Steven J

2017-01-22

At present, the zebrafish embryo is increasingly used as an alternative animal model to screen for developmental toxicity after exposure to xenobiotics. Since zebrafish embryos depend on their own drug-metabolizing capacity, knowledge of their intrinsic biotransformation is pivotal in order to correctly interpret the outcome of teratogenicity assays. Therefore, the aim of this in vitro study was to assess the activity of cytochrome P450 (CYP)-a group of drug-metabolizing enzymes-in microsomes from whole zebrafish embryos (ZEM) of 5, 24, 48, 72, 96 and 120 h post-fertilization (hpf) by means of a mammalian CYP substrate, i.e., benzyloxy-methyl-resorufin (BOMR). The same CYP activity assays were performed in adult zebrafish liver microsomes (ZLM) to serve as a reference for the embryos. In addition, activity assays with the human CYP3A4-specific Luciferin isopropyl acetal (Luciferin-IPA) as well as inhibition studies with ketoconazole and CYP3cide were carried out to identify CYP activity in ZLM. In the present study, biotransformation of BOMR was detected at 72 and 96 hpf; however, metabolite formation was low compared with ZLM. Furthermore, Luciferin-IPA was not metabolized by the zebrafish. In conclusion, the capacity of intrinsic biotransformation in zebrafish embryos appears to be lacking during a major part of organogenesis.

Fast and low-cost method for VBES bathymetry generation in coastal areas

Science.gov (United States)

Sánchez-Carnero, N.; Aceña, S.; Rodríguez-Pérez, D.; Couñago, E.; Fraile, P.; Freire, J.

2012-12-01

Sea floor topography is key information in coastal area management. Nowadays, LiDAR and multibeam technologies provide accurate bathymetries in those areas; however these methodologies are yet too expensive for small customers (fishermen associations, small research groups) willing to keep a periodic surveillance of environmental resources. In this paper, we analyse a simple methodology for vertical beam echosounder (VBES) bathymetric data acquisition and postprocessing, using low-cost means and free customizable tools such as ECOSONS and gvSIG (that is compared with industry standard ArcGIS). Echosounder data was filtered, resampled and, interpolated (using kriging or radial basis functions). Moreover, the presented methodology includes two data correction processes: Monte Carlo simulation, used to reduce GPS errors, and manually applied bathymetric line transformations, both improving the obtained results. As an example, we present the bathymetry of the Ría de Cedeira (Galicia, NW Spain), a good testbed area for coastal bathymetry methodologies given its extension and rich topography. The statistical analysis, performed by direct ground-truthing, rendered an upper bound of 1.7 m error, at 95% confidence level, and 0.7 m r.m.s. (cross-validation provided 30 cm and 25 cm, respectively). The methodology presented is fast and easy to implement, accurate outside transects (accuracy can be estimated), and can be used as a low-cost periodical monitoring method.

Analysis of Lethality and Malformations During Zebrafish (Danio rerio) Development.

Science.gov (United States)

Raghunath, Azhwar; Perumal, Ekambaram

2018-01-01

The versatility offered by zebrafish (Danio rerio) makes it a powerful and an attractive vertebrate model in developmental toxicity and teratogenicity assays. Apart from the newly introduced chemicals as drugs, xenobiotics also induce abnormal developmental abnormalities and congenital malformations in living organisms. Over the recent decades, zebrafish embryo/larva has emerged as a potential tool to test teratogenicity potential of these chemicals. Zebrafish responds to compounds as mammals do as they share similarities in their development, metabolism, physiology, and signaling pathways with that of mammals. The methodology used by the different scientists varies enormously in the zebrafish embryotoxicity test. In this chapter, we present methods to assess lethality and malformations during zebrafish development. We propose two major malformations scoring systems: binomial and relative morphological scoring systems to assess the malformations in zebrafish embryos/larvae. Based on the scoring of the malformations, the test compound can be classified as a teratogen or a nonteratogen and its teratogenic potential is evaluated.

Characterization of behavioral and endocrine effects of LSD on zebrafish.

Science.gov (United States)

Grossman, Leah; Utterback, Eli; Stewart, Adam; Gaikwad, Siddharth; Chung, Kyung Min; Suciu, Christopher; Wong, Keith; Elegante, Marco; Elkhayat, Salem; Tan, Julia; Gilder, Thomas; Wu, Nadine; Dileo, John; Cachat, Jonathan; Kalueff, Allan V

2010-12-25

Lysergic acid diethylamide (LSD) is a potent hallucinogenic drug that strongly affects animal and human behavior. Although adult zebrafish (Danio rerio) are emerging as a promising neurobehavioral model, the effects of LSD on zebrafish have not been investigated previously. Several behavioral paradigms (the novel tank, observation cylinder, light-dark box, open field, T-maze, social preference and shoaling tests), as well as modern video-tracking tools and whole-body cortisol assay were used to characterize the effects of acute LSD in zebrafish. While lower doses (5-100 microg/L) did not affect zebrafish behavior, 250 microg/L LSD increased top dwelling and reduced freezing in the novel tank and observation cylinder tests, also affecting spatiotemporal patterns of activity (as assessed by 3D reconstruction of zebrafish traces and ethograms). LSD evoked mild thigmotaxis in the open field test, increased light behavior in the light-dark test, reduced the number of arm entries and freezing in the T-maze and social preference test, without affecting social preference. In contrast, LSD affected zebrafish shoaling (increasing the inter-fish distance in a group), and elevated whole-body cortisol levels. Overall, our findings show sensitivity of zebrafish to LSD action, and support the use of zebrafish models to study hallucinogenic drugs of abuse. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Two novel approaches used to produce biodiesel from low-cost feedstocks

Energy Technology Data Exchange (ETDEWEB)

Fan, X.; Chen, F. [Clemson Univ., SC (United States). Dept. of Food Science and Human Nutrition; Wang, X. [Clemson Univ., SC (United States). Dept. of Genetics and Biochemistry

2010-07-01

The cost of feedstock has a significant effect of the economic viability of biodiesel production. The paper discussed a preliminary study looking at 2 approaches used to economically produce biodiesel, one from waste cooking oil (WCO) and the other from flaked cottonseed. Ultrasound-assisted synthesis was used to produce biodiesel from WCO, and in situ transesterification was used to produce biodiesel from the flaked cottonseed. The use of WCO solves the problem of waste disposal and also generates an environmentally benign fuel while at the same time lowering the costs involved in producing biodiesel. Ultrasonification has proven to be an efficient, low-cost, energy saving means of producing biodiesel. In situ transesterification makes solvent extraction and oil cleanup prior to biodiesel synthesis unnecessary, thereby simplifying the reaction steps. Based on the results of gas chromatography and high-performance liquid chromatography tests, both approaches are feasible for the production of biodiesel from low-cost feedstock. 15 refs., 4 figs.

A Low-Cost Digital Microscope with Real-Time Fluorescent Imaging Capability.

Science.gov (United States)

Hasan, Md Mehedi; Alam, Mohammad Wajih; Wahid, Khan A; Miah, Sayem; Lukong, Kiven Erique

2016-01-01

This paper describes the development of a prototype of a low-cost digital fluorescent microscope built from commercial off-the-shelf (COTS) components. The prototype was tested to detect malignant tumor cells taken from a living organism in a preclinical setting. This experiment was accomplished by using Alexa Fluor 488 conjugate dye attached to the cancer cells. Our prototype utilizes a torch along with an excitation filter as a light source for fluorophore excitation, a dichroic mirror to reflect the excitation and pass the emitted green light from the sample under test and a barrier filter to permit only appropriate wavelength. The system is designed out of a microscope using its optical zooming property and an assembly of exciter filter, dichroic mirror and transmitter filter. The microscope is connected to a computer or laptop through universal serial bus (USB) that allows real-time transmission of captured florescence images; this also offers real-time control of the microscope. The designed system has comparable features of high-end commercial fluorescent microscopes while reducing cost, power, weight and size.

A Low-Cost Digital Microscope with Real-Time Fluorescent Imaging Capability.

Directory of Open Access Journals (Sweden)

Md Mehedi Hasan

Full Text Available This paper describes the development of a prototype of a low-cost digital fluorescent microscope built from commercial off-the-shelf (COTS components. The prototype was tested to detect malignant tumor cells taken from a living organism in a preclinical setting. This experiment was accomplished by using Alexa Fluor 488 conjugate dye attached to the cancer cells. Our prototype utilizes a torch along with an excitation filter as a light source for fluorophore excitation, a dichroic mirror to reflect the excitation and pass the emitted green light from the sample under test and a barrier filter to permit only appropriate wavelength. The system is designed out of a microscope using its optical zooming property and an assembly of exciter filter, dichroic mirror and transmitter filter. The microscope is connected to a computer or laptop through universal serial bus (USB that allows real-time transmission of captured florescence images; this also offers real-time control of the microscope. The designed system has comparable features of high-end commercial fluorescent microscopes while reducing cost, power, weight and size.

A Low-Cost Digital Microscope with Real-Time Fluorescent Imaging Capability

Science.gov (United States)

Hasan, Md. Mehedi; Wahid, Khan A.; Miah, Sayem; Lukong, Kiven Erique

2016-01-01

This paper describes the development of a prototype of a low-cost digital fluorescent microscope built from commercial off-the-shelf (COTS) components. The prototype was tested to detect malignant tumor cells taken from a living organism in a preclinical setting. This experiment was accomplished by using Alexa Fluor 488 conjugate dye attached to the cancer cells. Our prototype utilizes a torch along with an excitation filter as a light source for fluorophore excitation, a dichroic mirror to reflect the excitation and pass the emitted green light from the sample under test and a barrier filter to permit only appropriate wavelength. The system is designed out of a microscope using its optical zooming property and an assembly of exciter filter, dichroic mirror and transmitter filter. The microscope is connected to a computer or laptop through universal serial bus (USB) that allows real-time transmission of captured florescence images; this also offers real-time control of the microscope. The designed system has comparable features of high-end commercial fluorescent microscopes while reducing cost, power, weight and size. PMID:27977709

Characterization of the Zebrafish Homolog of Zipper Interacting Protein Kinase

Directory of Open Access Journals (Sweden)

Brandon W. Carr

2014-06-01

Full Text Available Zipper-interacting protein kinase (ZIPK is a conserved vertebrate-specific regulator of actomyosin contractility in smooth muscle and non-muscle cells. Murine ZIPK has undergone an unusual divergence in sequence and regulation compared to other ZIPK orthologs. In humans, subcellular localization is controlled by phosphorylation of threonines 299 and 300. In contrast, ZIPK subcellular localization in mouse and rat is controlled by interaction with PAR-4. We carried out a comparative biochemical characterization of the regulation of the zebrafish ortholog of ZIPK. Like the human orthologs zebrafish ZIPK undergoes nucleocytoplasmic-shuttling and is abundant in the cytoplasm, unlike the primarily nuclear rat ZIPK. Rat ZIPK, but not human or zebrafish ZIPK, interacts with zebrafish PAR-4. Mutation of the conserved residues required for activation of the mammalian orthologs abrogated activity of the zebrafish ZIPK. In contrast to the human ortholog, mutation of threonine 299 and 300 in the zebrafish ZIPK has no effect on the activity or subcellular localization. Thus, we found that zebrafish ZIPK functions in a manner most similar to the human ZIPK and quite distinct from murine orthologs, yet the regulation of subcellular localization is not conserved.

A zebrafish model of inflammatory lymphangiogenesis

Directory of Open Access Journals (Sweden)

Kazuhide S. Okuda

2015-10-01

Full Text Available Inflammatory bowel disease (IBD is a disabling chronic inflammatory disease of the gastrointestinal tract. IBD patients have increased intestinal lymphatic vessel density and recent studies have shown that this may contribute to the resolution of IBD. However, the molecular mechanisms involved in IBD-associated lymphangiogenesis are still unclear. In this study, we established a novel inflammatory lymphangiogenesis model in zebrafish larvae involving colitogenic challenge stimulated by exposure to 2,4,6-trinitrobenzenesulfonic acid (TNBS or dextran sodium sulphate (DSS. Treatment with either TNBS or DSS resulted in vascular endothelial growth factor receptor (Vegfr-dependent lymphangiogenesis in the zebrafish intestine. Reduction of intestinal inflammation by the administration of the IBD therapeutic, 5-aminosalicylic acid, reduced intestinal lymphatic expansion. Zebrafish macrophages express vascular growth factors vegfaa, vegfc and vegfd and chemical ablation of these cells inhibits intestinal lymphatic expansion, suggesting that the recruitment of macrophages to the intestine upon colitogenic challenge is required for intestinal inflammatory lymphangiogenesis. Importantly, this study highlights the potential of zebrafish as an inflammatory lymphangiogenesis model that can be used to investigate the role and mechanism of lymphangiogenesis in inflammatory diseases such as IBD.

Cloning, characterization, and heat stress-induced redistribution of a protein homologous to human hsp27 in the zebrafish Danio rerio

International Nuclear Information System (INIS)

Mao Li; Bryantsev, Anton L.; Chechenova, Maria B.; Shelden, Eric A.

2005-01-01

Hsp27 is a small heat shock protein (shsp) regulating stress tolerance and increasingly thought to play roles in tissue homeostasis and differentiation. The zebrafish Danio rerio is an important model for the study of developmental processes, but little is known regarding shsps in this animal. Here, we report the sequence, expression, regulation, and function of a zebrafish protein (zfHsp27) homologous to human Hsp27. zfHsp27 contains three conserved phosphorylatable serines and a cysteine important for regulation of apoptosis, but it lacks much of a C-terminal tail domain and shows low homology in two putative actin interacting domains that are features of mammalian Hsp27. zfHsp27 mRNA is most abundant in adult skeletal muscle and heart and is upregulated during early embryogenesis. zfHsp27 expressed in mammalian fibroblasts was phosphorylated in response to heat stress and anisomycin, and this phosphorylation was prevented by treatment with SB202190, an inhibitor of p38 MAPK. Expression of zfHsp27 and human Hsp27 in mammalian fibroblasts promoted a similar degree of tolerance to heat stress. zfHsp27 fusion proteins entered the nucleus and associated with the cytoskeleton of heat stressed cells in vitro and in zebrafish embryos. These results reveal conservation in regulation and function of mammalian and teleost Hsp27 proteins and define zebrafish as a new model for the study of Hsp27 function

Low-Cost Precursors to Novel Hydrogen Storage Materials

Energy Technology Data Exchange (ETDEWEB)

Suzanne W. Linehan; Arthur A. Chin; Nathan T. Allen; Robert Butterick; Nathan T. Kendall; I. Leo Klawiter; Francis J. Lipiecki; Dean M. Millar; David C. Molzahn; Samuel J. November; Puja Jain; Sara Nadeau; Scott Mancroni

2010-12-31

From 2005 to 2010, The Dow Chemical Company (formerly Rohm and Haas Company) was a member of the Department of Energy Center of Excellence on Chemical Hydrogen Storage, which conducted research to identify and develop chemical hydrogen storage materials having the potential to achieve DOE performance targets established for on-board vehicular application. In collaboration with Center co-leads Los Alamos National Laboratory (LANL) and Pacific Northwest National Laboratory (PNNL), and other Center partners, Dow's efforts were directed towards defining and evaluating novel chemistries for producing chemical hydrides and processes for spent fuel regeneration. In Phase 1 of this project, emphasis was placed on sodium borohydride (NaBH{sub 4}), long considered a strong candidate for hydrogen storage because of its high hydrogen storage capacity, well characterized hydrogen release chemistry, safety, and functionality. Various chemical pathways for regenerating NaBH{sub 4} from spent sodium borate solution were investigated, with the objective of meeting the 2010/2015 DOE targets of $2-3/gal gasoline equivalent at the pump ($2-3/kg H{sub 2}) for on-board hydrogen storage systems and an overall 60% energy efficiency. With the September 2007 No-Go decision for NaBH{sub 4} as an on-board hydrogen storage medium, focus was shifted to ammonia borane (AB) for on-board hydrogen storage and delivery. However, NaBH{sub 4} is a key building block to most boron-based fuels, and the ability to produce NaBH{sub 4} in an energy-efficient, cost-effective, and environmentally sound manner is critical to the viability of AB, as well as many leading materials under consideration by the Metal Hydride Center of Excellence. Therefore, in Phase 2, research continued towards identifying and developing a single low-cost NaBH4 synthetic route for cost-efficient AB first fill, and conducting baseline cost estimates for first fill and regenerated AB using a variety of synthetic routes. This

Three-dimensional assemblies of graphene prepared by a novel chemical reduction-induced self-assembly method

KAUST Repository

Zhang, Lianbin

2012-01-01

In this study, three-dimensional (3D) graphene assemblies are prepared from graphene oxide (GO) by a facile in situ reduction-assembly method, using a novel, low-cost, and environment-friendly reducing medium which is a combination of oxalic acid (OA) and sodium iodide (NaI). It is demonstrated that the combination of a reducing acid, OA, and NaI is indispensable for effective reduction of GO in the current study and this unique combination (1) allows for tunable control over the volume of the thus-prepared graphene assemblies and (2) enables 3D graphene assemblies to be prepared from the GO suspension with a wide range of concentrations (0.1 to 4.5 mg mL-1). To the best of our knowledge, the GO concentration of 0.1 mg mL-1 is the lowest GO concentration ever reported for preparation of 3D graphene assemblies. The thus-prepared 3D graphene assemblies exhibit low density, highly porous structures, and electrically conducting properties. As a proof of concept, we show that by infiltrating a responsive polymer of polydimethylsiloxane (PDMS) into the as-resulted 3D conducting network of graphene, a conducting composite is obtained, which can be used as a sensing device for differentiating organic solvents with different polarity. © 2012 The Royal Society of Chemistry.

Genetic determinants of hyaloid and retinal vasculature in zebrafish

Directory of Open Access Journals (Sweden)

Hyde David R

2007-10-01

Full Text Available Abstract Background The retinal vasculature is a capillary network of blood vessels that nourishes the inner retina of most mammals. Developmental abnormalities or microvascular complications in the retinal vasculature result in severe human eye diseases that lead to blindness. To exploit the advantages of zebrafish for genetic, developmental and pharmacological studies of retinal vasculature, we characterised the intraocular vasculature in zebrafish. Results We show a detailed morphological and developmental analysis of the retinal blood supply in zebrafish. Similar to the transient hyaloid vasculature in mammalian embryos, vessels are first found attached to the zebrafish lens at 2.5 days post fertilisation. These vessels progressively lose contact with the lens and by 30 days post fertilisation adhere to the inner limiting membrane of the juvenile retina. Ultrastructure analysis shows these vessels to exhibit distinctive hallmarks of mammalian retinal vasculature. For example, smooth muscle actin-expressing pericytes are ensheathed by the basal lamina of the blood vessel, and vesicle vacuolar organelles (VVO, subcellular mediators of vessel-retinal nourishment, are present. Finally, we identify 9 genes with cell membrane, extracellular matrix and unknown identity that are necessary for zebrafish hyaloid and retinal vasculature development. Conclusion Zebrafish have a retinal blood supply with a characteristic developmental and adult morphology. Abnormalities of these intraocular vessels are easily observed, enabling application of genetic and chemical approaches in zebrafish to identify molecular regulators of hyaloid and retinal vasculature in development and disease.

HCV IRES-mediated core expression in zebrafish.

Directory of Open Access Journals (Sweden)

Ye Zhao

Full Text Available The lack of small animal models for hepatitis C virus has impeded the discovery and development of anti-HCV drugs. HCV-IRES plays an important role in HCV gene expression, and is an attractive target for antiviral therapy. In this study, we report a zebrafish model with a biscistron expression construct that can co-transcribe GFP and HCV-core genes by human hepatic lipase promoter and zebrafish liver fatty acid binding protein enhancer. HCV core translation was designed mediated by HCV-IRES sequence and gfp was by a canonical cap-dependent mechanism. Results of fluorescence image and in situ hybridization indicate that expression of HCV core and GFP is liver-specific; RT-PCR and Western blotting show that both core and gfp expression are elevated in a time-dependent manner for both transcription and translation. It means that the HCV-IRES exerted its role in this zebrafish model. Furthermore, the liver-pathological impact associated with HCV-infection was detected by examination of gene markers and some of them were elevated, such as adiponectin receptor, heparanase, TGF-β, PDGF-α, etc. The model was used to evaluate three clinical drugs, ribavirin, IFNα-2b and vitamin B12. The results show that vitamin B12 inhibited core expression in mRNA and protein levels in dose-dependent manner, but failed to impact gfp expression. Also VB12 down-regulated some gene transcriptions involved in fat liver, liver fibrosis and HCV-associated pathological process in the larvae. It reveals that HCV-IRES responds to vitamin B12 sensitively in the zebrafish model. Ribavirin did not disturb core expression, hinting that HCV-IRES is not a target site of ribavirin. IFNα-2b was not active, which maybe resulted from its degradation in vivo for the long time. These findings demonstrate the feasibility of the zebrafish model for screening of anti-HCV drugs targeting to HCV-IRES. The zebrafish system provides a novel evidence of using zebrafish as a HCV model organism.

Silver nanoparticles induce endoplasmatic reticulum stress response in zebrafish

Energy Technology Data Exchange (ETDEWEB)

Christen, Verena [University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH-4132 Muttenz (Switzerland); Capelle, Martinus [Crucell, P.O. Box 2048, NL-2301 Leiden (Netherlands); Fent, Karl, E-mail: karl.fent@fhnw.ch [University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH-4132 Muttenz (Switzerland); Swiss Federal Institute of Technology Zürich, Department of Environmental Systems Science, CH-8092 Zürich (Switzerland)

2013-10-15

Silver nanoparticles (AgNPs) find increasing applications, and therefore humans and the environment are increasingly exposed to them. However, potential toxicological implications are not sufficiently known. Here we investigate effects of AgNPs (average size 120 nm) on zebrafish in vitro and in vivo, and compare them to human hepatoma cells (Huh7). AgNPs are incorporated in zebrafish liver cells (ZFL) and Huh7, and in zebrafish embryos. In ZFL cells AgNPs lead to induction of reactive oxygen species (ROS), endoplasmatic reticulum (ER) stress response, and TNF-α. Transcriptional alterations also occur in pro-apoptotic genes p53 and Bax. The transcriptional profile differed in ZFL and Huh7 cells. In ZFL cells, the ER stress marker BiP is induced, concomitant with the ER stress marker ATF-6 and spliced XBP-1 after 6 h and 24 h exposure to 0.5 g/L and 0.05 g/L AgNPs, respectively. This indicates the induction of different pathways of the ER stress response. Moreover, AgNPs induce TNF-α. In zebrafish embryos exposed to 0.01, 0.1, 1 and 5 mg/L AgNPs hatching was affected and morphological defects occurred at high concentrations. ER stress related gene transcripts BiP and Synv are significantly up-regulated after 24 h at 0.1 and 5 mg/L AgNPs. Furthermore, transcriptional alterations occurred in the pro-apoptotic genes Noxa and p21. The ER stress response was strong in ZFL cells and occurred in zebrafish embryos as well. Our data demonstrate for the first time that AgNPs lead to induction of ER stress in zebrafish. The induction of ER stress can have several consequences including the activation of apoptotic and inflammatory pathways. - Highlights: • Effects of silver nanoparticles (120 nm AgNPs) are investigated in zebrafish. • AgNPs induce all ER stress reponses in vitro in zebrafish liver cells. • AgNPs induce weak ER stress in zebrafish embryos. • AgNPs induce oxidative stress and transcripts of pro-apoptosis genes.

Silver nanoparticles induce endoplasmatic reticulum stress response in zebrafish

International Nuclear Information System (INIS)

Christen, Verena; Capelle, Martinus; Fent, Karl

2013-01-01

Silver nanoparticles (AgNPs) find increasing applications, and therefore humans and the environment are increasingly exposed to them. However, potential toxicological implications are not sufficiently known. Here we investigate effects of AgNPs (average size 120 nm) on zebrafish in vitro and in vivo, and compare them to human hepatoma cells (Huh7). AgNPs are incorporated in zebrafish liver cells (ZFL) and Huh7, and in zebrafish embryos. In ZFL cells AgNPs lead to induction of reactive oxygen species (ROS), endoplasmatic reticulum (ER) stress response, and TNF-α. Transcriptional alterations also occur in pro-apoptotic genes p53 and Bax. The transcriptional profile differed in ZFL and Huh7 cells. In ZFL cells, the ER stress marker BiP is induced, concomitant with the ER stress marker ATF-6 and spliced XBP-1 after 6 h and 24 h exposure to 0.5 g/L and 0.05 g/L AgNPs, respectively. This indicates the induction of different pathways of the ER stress response. Moreover, AgNPs induce TNF-α. In zebrafish embryos exposed to 0.01, 0.1, 1 and 5 mg/L AgNPs hatching was affected and morphological defects occurred at high concentrations. ER stress related gene transcripts BiP and Synv are significantly up-regulated after 24 h at 0.1 and 5 mg/L AgNPs. Furthermore, transcriptional alterations occurred in the pro-apoptotic genes Noxa and p21. The ER stress response was strong in ZFL cells and occurred in zebrafish embryos as well. Our data demonstrate for the first time that AgNPs lead to induction of ER stress in zebrafish. The induction of ER stress can have several consequences including the activation of apoptotic and inflammatory pathways. - Highlights: • Effects of silver nanoparticles (120 nm AgNPs) are investigated in zebrafish. • AgNPs induce all ER stress reponses in vitro in zebrafish liver cells. • AgNPs induce weak ER stress in zebrafish embryos. • AgNPs induce oxidative stress and transcripts of pro-apoptosis genes

Characterization of Na+ and Ca2+ channels in zebrafish dorsal root ganglion neurons.

Directory of Open Access Journals (Sweden)

Yu-Jin Won

Full Text Available BACKGROUND: Dorsal root ganglia (DRG somata from rodents have provided an excellent model system to study ion channel properties and modulation using electrophysiological investigation. As in other vertebrates, zebrafish (Danio rerio DRG are organized segmentally and possess peripheral axons that bifurcate into each body segment. However, the electrical properties of zebrafish DRG sensory neurons, as compared with their mammalian counterparts, are relatively unexplored because a preparation suitable for electrophysiological studies has not been available. METHODOLOGY/PRINCIPAL FINDINGS: We show enzymatically dissociated DRG neurons from juvenile zebrafish expressing Isl2b-promoter driven EGFP were easily identified with fluorescence microscopy and amenable to conventional whole-cell patch-clamp studies. Two kinetically distinct TTX-sensitive Na(+ currents (rapidly- and slowly-inactivating were discovered. Rapidly-inactivating I(Na were preferentially expressed in relatively large neurons, while slowly-inactivating I(Na was more prevalent in smaller DRG neurons. RT-PCR analysis suggests zscn1aa/ab, zscn8aa/ab, zscn4ab and zscn5Laa are possible candidates for these I(Na components. Voltage-gated Ca(2+ currents (I(Ca were primarily (87% comprised of a high-voltage activated component arising from ω-conotoxin GVIA-sensitive Ca(V2.2 (N-type Ca(2+ channels. A few DRG neurons (8% displayed a miniscule low-voltage-activated component. I(Ca in zebrafish DRG neurons were modulated by neurotransmitters via either voltage-dependent or -independent G-protein signaling pathway with large cell-to-cell response variability. CONCLUSIONS/SIGNIFICANCE: Our present results indicate that, as in higher vertebrates, zebrafish DRG neurons are heterogeneous being composed of functionally distinct subpopulations that may correlate with different sensory modalities. These findings provide the first comparison of zebrafish and rodent DRG neuron electrical properties and

Low-Cost Air Quality Monitoring Tools: From Research to Practice (A Workshop Summary

Directory of Open Access Journals (Sweden)

Andrea L. Clements

2017-10-01

Full Text Available In May 2017, a two-day workshop was held in Los Angeles (California, U.S.A. to gather practitioners who work with low-cost sensors used to make air quality measurements. The community of practice included individuals from academia, industry, non-profit groups, community-based organizations, and regulatory agencies. The group gathered to share knowledge developed from a variety of pilot projects in hopes of advancing the collective knowledge about how best to use low-cost air quality sensors. Panel discussion topics included: (1 best practices for deployment and calibration of low-cost sensor systems, (2 data standardization efforts and database design, (3 advances in sensor calibration, data management, and data analysis and visualization, and (4 lessons learned from research/community partnerships to encourage purposeful use of sensors and create change/action. Panel discussions summarized knowledge advances and project successes while also highlighting the questions, unresolved issues, and technological limitations that still remain within the low-cost air quality sensor arena.

Culturable gut microbiota diversity in zebrafish.

Science.gov (United States)

Cantas, Leon; Sørby, Jan Roger Torp; Aleström, Peter; Sørum, Henning

2012-03-01

The zebrafish (Danio rerio) is an increasingly used laboratory animal model in basic biology and biomedicine, novel drug development, and toxicology. The wide use has increased the demand for optimized husbandry protocols to ensure animal health care and welfare. The knowledge about the correlation between culturable zebrafish intestinal microbiota and health in relation to environmental factors and management procedures is very limited. A semi-quantitative level of growth of individual types of bacteria was determined and associated with sampling points. A total of 72 TAB line zebrafish from four laboratories (Labs A-D) in the Zebrafish Network Norway were used. Diagnostic was based on traditional bacterial culture methods and biochemical characterization using commercial kits, followed by 16S rDNA gene sequencing from pure subcultures. Also selected Gram-negative isolates were analyzed for antibiotic susceptibility to 8 different antibiotics. A total of 13 morphologically different bacterial species were the most prevalent: Aeromonas hydrophila, Aeromonas sobria, Vibrio parahaemolyticus, Photobacterium damselae, Pseudomonas aeruginosa, Pseudomonas fluorescens, Pseudomonas luteola, Comamonas testosteroni, Ochrobactrum anthropi, Staphylococcus cohnii, Staphylococcus epidermidis, Staphylococcus capitis, and Staphylococcus warneri. Only Lab B had significantly higher levels of total bacterial growth (OR=2.03), whereas numbers from Lab C (OR=1.01) and Lab D (OR=1.12) were found to be similar to the baseline Lab A. Sexually immature individuals had a significantly higher level of harvested total bacterial growth than mature fish (OR=0.82), no statistically significant differences were found between male and female fish (OR=1.01), and the posterior intestinal segment demonstrated a higher degree of culturable bacteria than the anterior segment (OR=4.1). Multiple antibiotic (>3) resistance was observed in 17% of the strains. We propose that a rapid conventional

Low-cost, easy-to-prepare magnetic chitosan microparticles for enzymes immobilization

Czech Academy of Sciences Publication Activity Database

Pospišková, K.; Šafařík, Ivo

2013-01-01

Roč. 96, č. 2 (2013), s. 545-548 ISSN 0144-8617 R&D Projects: GA MŠk(CZ) LD13021 Institutional support: RVO:67179843 Keywords : Chitosan * Magnetite * Microwave irradiation * Enzymes immobilization Subject RIV: CE - Biochemistry Impact factor: 3.916, year: 2013

A Printed Xi-Shaped Left-Handed Metamaterial on Low-Cost Flexible Photo Paper.

Science.gov (United States)

Ashraf, Farhad Bin; Alam, Touhidul; Islam, Mohammad Tariqul

2017-07-05

A Xi-shaped meta structure, has been introduced in this paper. A modified split-ring resonator (MSRR) and a capacitive loaded strip (CLS) were used to achieve the left-handed property of the metamaterial. The structure was printed using silver metallic nanoparticle ink, using a very low-cost photo paper as a substrate material. Resonators were inkjet-printed using silver nanoparticle metallic ink on paper to make this metamaterial flexible. It is also free from any kind of chemical waste, which makes it eco-friendly. A double negative region from 8.72 GHz to 10.91 GHz (bandwidth of 2.19 GHz) in the X-band microwave spectra was been found. Figure of merit was also obtained to measure any loss in the double negative region. The simulated result was verified by the performance of the fabricated prototype. The total dimensions of the proposed structure were 0.29 λ × 0.29 λ × 0.007 λ . It is a promising unit cell because of its simplicity, cost-effectiveness, and easy fabrication process.

Development of a low-cost whole body counter

International Nuclear Information System (INIS)

Smith, M.H.; Gross, G.P.

1991-01-01

This paper documents the construction and calibration of a whole-body counter for the Radiation Safety Office of the Mayo Clinic in Rochester, MN. Changes in the federal regulations may require improved documentation of internal dose for radiation workers. A relatively inexpensive and simple chair-type whole-body counter may suit the needs of many organizations for in vivo assessment of gamma emitting radionuclides. A simple calibration phantom and a spreadsheet computer program were developed in conjunction with the counter. The spreadsheet can be used to calculate an estimate of committed effective dose equivalent based on activity in a subject and data from ICRP Publication 30. Using a count time of 10 minutes, the counter's minimum detectable activity ranged from 370 Bq to 1,110 Bq for 60 Co and 57 Co respectively. Other institutions will be able to assemble whole-body counters at low cost, often from surplus components. The spreadsheet is easily adapted to the needs of any institution and uses current methodology to estimate internal dose

Transcriptome analysis of zebrafish embryogenesis using microarrays.

Directory of Open Access Journals (Sweden)

Sinnakaruppan Mathavan

2005-08-01

Full Text Available Zebrafish (Danio rerio is a well-recognized model for the study of vertebrate developmental genetics, yet at the same time little is known about the transcriptional events that underlie zebrafish embryogenesis. Here we have employed microarray analysis to study the temporal activity of developmentally regulated genes during zebrafish embryogenesis. Transcriptome analysis at 12 different embryonic time points covering five different developmental stages (maternal, blastula, gastrula, segmentation, and pharyngula revealed a highly dynamic transcriptional profile. Hierarchical clustering, stage-specific clustering, and algorithms to detect onset and peak of gene expression revealed clearly demarcated transcript clusters with maximum gene activity at distinct developmental stages as well as co-regulated expression of gene groups involved in dedicated functions such as organogenesis. Our study also revealed a previously unidentified cohort of genes that are transcribed prior to the mid-blastula transition, a time point earlier than when the zygotic genome was traditionally thought to become active. Here we provide, for the first time to our knowledge, a comprehensive list of developmentally regulated zebrafish genes and their expression profiles during embryogenesis, including novel information on the temporal expression of several thousand previously uncharacterized genes. The expression data generated from this study are accessible to all interested scientists from our institute resource database (http://giscompute.gis.a-star.edu.sg/~govind/zebrafish/data_download.html.

A low-cost machine vision system for the recognition and sorting of small parts

Science.gov (United States)

Barea, Gustavo; Surgenor, Brian W.; Chauhan, Vedang; Joshi, Keyur D.

2018-04-01

An automated machine vision-based system for the recognition and sorting of small parts was designed, assembled and tested. The system was developed to address a need to expose engineering students to the issues of machine vision and assembly automation technology, with readily available and relatively low-cost hardware and software. This paper outlines the design of the system and presents experimental performance results. Three different styles of plastic gears, together with three different styles of defective gears, were used to test the system. A pattern matching tool was used for part classification. Nine experiments were conducted to demonstrate the effects of changing various hardware and software parameters, including: conveyor speed, gear feed rate, classification, and identification score thresholds. It was found that the system could achieve a maximum system accuracy of 95% at a feed rate of 60 parts/min, for a given set of parameter settings. Future work will be looking at the effect of lighting.

Microcystin-LR exposure induces developmental neurotoxicity in zebrafish embryo

International Nuclear Information System (INIS)

Wu, Qin; Yan, Wei; Liu, Chunsheng; Li, Li; Yu, Liqin; Zhao, Sujuan; Li, Guangyu

2016-01-01

Microcystin-LR (MCLR) is a commonly acting potent hepatotoxin and has been pointed out of potentially causing developmental neurotoxicity, but the exact mechanism is little known. In this study, zebrafish embryos were exposed to 0, 0.8, 1.6 or 3.2 mg/L MCLR for 120 h. MCLR exposure through submersion caused serious hatching delay and body length decrease. The content of MCLR in zebrafish larvae was analyzed and the results demonstrated that MCLR can accumulate in zebrafish larvae. The locomotor speed of zebrafish larvae was decreased. Furthermore, the dopamine and acetylcholine (ACh) content were detected to be significantly decreased in MCLR exposure groups. And the acetylcholinesterase (AChE) activity was significantly increased after exposure to 1.6 and 3.2 mg/L MCLR. The transcription pattern of manf, chrnα7 and ache gene was consistent with the change of the dopamine content, ACh content and AChE activity. Gene expression involved in the development of neurons was also measured. α1-tubulin and shha gene expression were down-regulated, whereas mbp and gap43 gene expression were observed to be significantly up-regulated upon exposure to MCLR. The above results indicated that MCLR-induced developmental toxicity might attribute to the disorder of cholinergic system, dopaminergic signaling, and the development of neurons. - Highlights: • MCLR accumulation induces developmental neurotoxicity in zebrafish embryo. • The decrease of dopamine levels might be associated with the MCLR-induced developmental neurotoxicity in zebrafish larvae. • The alternation of cholinergic system might contribute to the change of neurobehavior in zebrafish larvae exposure with MCLR. - MCLR accumulation induces developmental neurotoxicity by affecting cholinergic system, dopaminergic signaling, and the development of neurons in zebrafish embryo.

Low Cost, Low Power, High Sensitivity Magnetometer

Science.gov (United States)

2008-12-01

which are used to measure the small magnetic signals from brain. Other types of vector magnetometers are fluxgate , coil based, and magnetoresistance...concentrator with the magnetometer currently used in Army multimodal sensor systems, the Brown fluxgate . One sees the MEMS fluxgate magnetometer is...Guedes, A.; et al., 2008: Hybrid - LOW COST, LOW POWER, HIGH SENSITIVITY MAGNETOMETER A.S. Edelstein*, James E. Burnette, Greg A. Fischer, M.G